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Waszczuk W, Czajkowska J, Dutkiewicz A, Klasa B, Carolak E, Aleksandrowicz A, Grzymajlo K. It takes two to attach - endo-1,3-β-d-glucanase as a potential receptor of mannose-independent, FimH-dependent Salmonella Typhimurium binding to spinach leaves. Food Microbiol 2024; 121:104519. [PMID: 38637081 DOI: 10.1016/j.fm.2024.104519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 03/07/2024] [Accepted: 03/09/2024] [Indexed: 04/20/2024]
Abstract
Currently, fresh, unprocessed food has become a relevant element of the chain of transmission of enteropathogenic infections. To survive on a plant surface and further spread the infections, pathogens like Salmonella have to attach stably to the leaf surface. Adhesion, driven by various virulence factors, including the most abundant fim operon encoding type 1 fimbriae, is usually an initial step of infection, preventing physical removal of the pathogen. Adhesion properties of Salmonella's type 1 fimbriae and its FimH adhesin were investigated intensively in the past. However, there is a lack of knowledge regarding its role in interaction with plant cells. Understanding the mechanisms and structures involved in such interaction may facilitate efforts to decrease the risk of contamination and increase fresh food safety. Here, we applied Salmonella genome site-directed mutagenesis, adhesion assays, protein-protein interactions, and biophysics methods based on surface plasmon resonance to unravel the role of FimH adhesin in interaction with spinach leaves. We show that FimH is at least partially responsible for Salmonella binding to spinach leaves, and this interaction occurs in a mannose-independent manner. Importantly, we identified a potential FimH receptor as endo-1,3-β-d-Glucanase and found that this interaction is strong and specific, with a dissociation constant in the nanomolar range. This research advances our comprehension of Salmonella's interactions with plant surfaces, offering insights that can aid in minimizing contamination risks and improving the safety of fresh, unprocessed foods.
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Affiliation(s)
- Wiktoria Waszczuk
- Wrocław University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Department of Biochemistry and Molecular Biology, Poland.
| | - Joanna Czajkowska
- Wrocław University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Department of Biochemistry and Molecular Biology, Poland.
| | - Agata Dutkiewicz
- Wrocław University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Department of Biochemistry and Molecular Biology, Poland.
| | - Beata Klasa
- Wrocław University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Department of Biochemistry and Molecular Biology, Poland.
| | - Ewa Carolak
- Wrocław University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Department of Biochemistry and Molecular Biology, Poland.
| | - Adrianna Aleksandrowicz
- Wrocław University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Department of Biochemistry and Molecular Biology, Poland.
| | - Krzysztof Grzymajlo
- Wrocław University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Department of Biochemistry and Molecular Biology, Poland.
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Zhai Y, Tian W, Chen K, Lan L, Kan J, Shi H. Flagella-mediated adhesion of Escherichia coli O157:H7 to surface of stainless steel, glass and fresh produces during sublethal injury and recovery. Food Microbiol 2024; 117:104383. [PMID: 37918998 DOI: 10.1016/j.fm.2023.104383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/06/2023] [Accepted: 09/10/2023] [Indexed: 11/04/2023]
Abstract
E. coli O157:H7 can be induced into sublethally injured (SI) state by lactic acid (LA) and regain activity in nutrient environments. This research clarified the role of flagella-related genes (fliD, fliS, cheA and motA) in adhesion of E. coli O157:H7 onto stainless steel, glass, lettuce, spinach, red cabbage and cucumber during LA-induced SI and recovery by plate counting. Results of adhesion showed improper flagellar rotation caused by the deletion of motA resulting in the decreased adhesion. Motility of wildtype determined by diameter of motility halo decreased in SI state and repaired with recovery time increasing, lagging behind changes in expression of flagella-related genes. Flagellar function-impaired strains all exhibited non-motile property. Thus, we speculated that flagella-mediated motility is critical in early stage of adhesion. We also found the effects of Fe2+, Ca2+ and Mn2+ on adhesion or motility of wildtype was independent of bacterial states. However, the addition of Ca2+ and Mn2+ did not affect motility of flagellar function-impaired strains as they did on wildtype. This research provides new insights to understand the role of flagella and cations in bacterial adhesion, which will aid in development of anti-adhesion agents to reduce bio-contamination in food processing.
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Affiliation(s)
- Yujun Zhai
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Weina Tian
- College of Bioengineering, Beijing Polytechnic, Beijing, 100176, China
| | - Kewei Chen
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Linshu Lan
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Jianquan Kan
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Hui Shi
- College of Food Science, Southwest University, Chongqing, 400715, China.
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Hamed SA, Mohan A, Navaneetha Krishnan S, Wang A, Drikic M, Prince NL, Lewis IA, Shearer J, Keita ÅV, Söderholm JD, Shutt TE, McKay DM. Butyrate reduces adherent-invasive E. coli-evoked disruption of epithelial mitochondrial morphology and barrier function: involvement of free fatty acid receptor 3. Gut Microbes 2023; 15:2281011. [PMID: 38078655 PMCID: PMC10730202 DOI: 10.1080/19490976.2023.2281011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 11/05/2023] [Indexed: 12/18/2023] Open
Abstract
Gut bacteria provide benefits to the host and have been implicated in inflammatory bowel disease (IBD), where adherent-invasive E. coli (AIEC) pathobionts (e.g., strain LF82) are associated with Crohn's disease. E. coli-LF82 causes fragmentation of the epithelial mitochondrial network, leading to increased epithelial permeability. We hypothesized that butyrate would limit the epithelial mitochondrial disruption caused by E. coli-LF82. Human colonic organoids and the T84 epithelial cell line infected with E. coli-LF82 (MOI = 100, 4 h) showed a significant increase in mitochondrial network fission that was reduced by butyrate (10 mM) co-treatment. Butyrate reduced the loss of mitochondrial membrane potential caused by E. coli-LF82 and increased expression of PGC-1α mRNA, the master regulator of mitochondrial biogenesis. Metabolomics revealed that butyrate significantly altered E. coli-LF82 central carbon metabolism leading to diminished glucose uptake and increased succinate secretion. Correlating with preservation of mitochondrial network form/function, butyrate reduced E. coli-LF82 transcytosis across T84-cell monolayers. The use of the G-protein inhibitor, pertussis toxin, implicated GPCR signaling as critical to the effect of butyrate, and the free fatty acid receptor three (FFAR3, GPR41) agonist, AR420626, reproduced butyrate's effect in terms of ameliorating the loss of barrier function and reducing the mitochondrial fragmentation observed in E. coli-LF82 infected T84-cells and organoids. These data indicate that butyrate helps maintain epithelial mitochondrial form/function when challenged by E. coli-LF82 and that this occurs, at least in part, via FFAR3. Thus, loss of butyrate-producing bacteria in IBD in the context of pathobionts would contribute to loss of epithelial mitochondrial and barrier functions that could evoke disease and/or exaggerate a low-grade inflammation.
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Affiliation(s)
- Samira A. Hamed
- Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Armaan Mohan
- Departments of Medical Genetics and Biochemistry & Molecular Biology, Alberta Children’s Hospital Research Institute, Hotchkiss Brain Institute, Snyder Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Saranya Navaneetha Krishnan
- Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Arthur Wang
- Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Marija Drikic
- Calgary Metabolomics Research Facility, Department of Biological Sciences, Faculty of Science, University of Calgary, Calgary, Canada
| | - Nicole L. Prince
- Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Ian A. Lewis
- Calgary Metabolomics Research Facility, Department of Biological Sciences, Faculty of Science, University of Calgary, Calgary, Canada
| | - Jane Shearer
- Department of Biochemistry and Molecular Biology, Faculty of Kinesiology, University of Calgary, Calgary, Canada
| | - Åsa V. Keita
- Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology, Linköping University, Linköping, Sweden
| | - Johan D. Söderholm
- Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology, Linköping University, Linköping, Sweden
| | - Timothy E. Shutt
- Departments of Medical Genetics and Biochemistry & Molecular Biology, Alberta Children’s Hospital Research Institute, Hotchkiss Brain Institute, Snyder Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Derek M. McKay
- Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
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Yao T, Huang Y, Huai Z, Liu X, Liu X, Liu Y, Sun H, Pang Y. Response mechanisms to acid stress promote LF82 replication in macrophages. Front Cell Infect Microbiol 2023; 13:1255083. [PMID: 37881369 PMCID: PMC10595154 DOI: 10.3389/fcimb.2023.1255083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 09/25/2023] [Indexed: 10/27/2023] Open
Abstract
Background Adherent-invasive E. coli (AIEC) LF82 is capable of adhering to and invading intestinal epithelial cells, as well as replicating within macrophages without inducing host cell death. Methods We compared the transcriptomics of LF82 at pH=7.5 and pH=5.8 by RNA-sequencing, and qRT-PCR verified differentially expressed genes (DEGs). The deletion mutants of DEGs in the treatment group (pH=5.8) compared to the control group (pH=7.5) were constructed by λ recombinant. The replication differences between the mutants and WT infected Raw 264.7 at 24 h.p.i were analyzed by combining LB solid plate count and confocal observation. NH4Cl and chloroquine diphosphate (CQ) were used for acid neutralization to study the effect of pH on the replication of LF82 in macrophages. Na2NO3 was added to RPMI 1640 to study the effect of nitrate on the replication of LF82 in macrophages. 0.3% solid LB was used for flagellar motility assay and Hela was used to study flagellar gene deletion mutants and WT adhesion and invasion ability. Results In this study, we found that infection with LF82 results in acidification of macrophages. Subsequent experiments demonstrated that an intracellular acidic environment is necessary for LF82 replication. Transcriptome and phenotypic analysis showed that high expression of acid shock genes and acid fitness genes promotes LF82 replication in macrophages. Further, we found that the replication of LF82 in macrophages was increased under nitrate treatment, and nitrogen metabolism genes of LF82 were upregulated in acid treatment. The replication in macrophages of ΔnarK, ΔnarXL, ΔnarP, and Δhmp were decreased. In addition, we found that the expression of flagellar genes was downregulated in acidic pH and after LF82 invading macrophages. Motility assay shows that the movement of LF82 on an acidic semisolid agar plate was limited. Further results showed that ΔfliC and ΔfliD decreased in motility, adhesion ability, and invasion of host cells, but no significant effect on replication in macrophages was observed. Conclusion In this study, we simulated the acidic environment in macrophages, combined with transcriptome technology, and explained from the genetic level that LF82 promotes replication by activating its acid shock and fitness system, enhancing nitrate utilization, and inhibiting flagellar function.
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Affiliation(s)
- Ting Yao
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- The Key Laboratory of Molecular Microbiology and Technology, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Ministry of Education, Tianjin, China
| | - Yu Huang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- The Key Laboratory of Molecular Microbiology and Technology, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Ministry of Education, Tianjin, China
| | - Zimeng Huai
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- The Key Laboratory of Molecular Microbiology and Technology, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Ministry of Education, Tianjin, China
| | - Xingmei Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- The Key Laboratory of Molecular Microbiology and Technology, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Ministry of Education, Tianjin, China
| | - Xiaowen Liu
- Academy of Psychology and Behavior, Faculty of Psychology, Tianjin Normal University, Tianjin, China
| | - Yutao Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- The Key Laboratory of Molecular Microbiology and Technology, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Ministry of Education, Tianjin, China
| | - Hao Sun
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- The Key Laboratory of Molecular Microbiology and Technology, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Ministry of Education, Tianjin, China
| | - Yu Pang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- The Key Laboratory of Molecular Microbiology and Technology, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Ministry of Education, Tianjin, China
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Bonet-Rossinyol Q, Camprubí-Font C, López-Siles M, Martinez-Medina M. Identification of differences in gene expression implicated in the Adherent-Invasive Escherichia coli phenotype during in vitro infection of intestinal epithelial cells. Front Cell Infect Microbiol 2023; 13:1228159. [PMID: 37767199 PMCID: PMC10519790 DOI: 10.3389/fcimb.2023.1228159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 07/21/2023] [Indexed: 09/29/2023] Open
Abstract
Introduction Adherent-invasive Escherichia coli (AIEC) is strongly associated with the pathogenesis of Crohn's disease (CD). However, no molecular markers currently exist for AIEC identification. This study aimed to identify differentially expressed genes (DEGs) between AIEC and non-AIEC strains that may contribute to AIEC pathogenicity and to evaluate their utility as molecular markers. Methods Comparative transcriptomics was performed on two closely related AIEC/non-AIEC strain pairs during Intestine-407 cell infection. DEGs were quantified by RT-qPCR in the same RNA extracts, as well as in 14 AIEC and 23 non-AIEC strains to validate the results across a diverse strain collection. Binary logistical regression was performed to identify DEGs whose quantification could be used as AIEC biomarkers. Results Comparative transcriptomics revealed 67 differences in expression between the two phenotypes in the strain pairs, 50 of which (81.97%) were corroborated by RT-qPCR. When explored in the whole strain collection, 29 DEGs were differentially expressed between AIEC and non-AIEC phenotypes (p-value < 0.042), and 42 genes between the supernatant fraction of infected cell cultures and the cellular fraction containing adhered and intracellular bacteria (p-value < 0.049). Notably, six DEGs detected in the strain collection were implicated in arginine biosynthesis and five in colanic acid synthesis. Furthermore, two biomarkers based on wzb and cueR gene expression were proposed with an accuracy of ≥ 85% in our strain collection. Discussion This is the first transcriptomic study conducted using AIEC-infected cell cultures. We have identified several genes that may be involved in AIEC pathogenicity, two of which are putative biomarkers for identification.
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Chekli Y, Stevick RJ, Kornobis E, Briolat V, Ghigo JM, Beloin C. Escherichia coli Aggregates Mediated by Native or Synthetic Adhesins Exhibit Both Core and Adhesin-Specific Transcriptional Responses. Microbiol Spectr 2023; 11:e0069023. [PMID: 37039668 PMCID: PMC10269875 DOI: 10.1128/spectrum.00690-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 03/20/2023] [Indexed: 04/12/2023] Open
Abstract
Bacteria can rapidly tune their physiology and metabolism to adapt to environmental fluctuations. In particular, they can adapt their lifestyle to the close proximity of other bacteria or the presence of different surfaces. However, whether these interactions trigger transcriptomic responses is poorly understood. We used a specific setup of E. coli strains expressing native or synthetic adhesins mediating bacterial aggregation to study the transcriptomic changes of aggregated compared to nonaggregated bacteria. Our results show that, following aggregation, bacteria exhibit a core response independent of the adhesin type, with differential expression of 56.9% of the coding genome, including genes involved in stress response and anaerobic lifestyle. Moreover, when aggregates were formed via a naturally expressed E. coli adhesin (antigen 43), the transcriptomic response of the bacteria was more exaggerated than that of aggregates formed via a synthetic adhesin. This suggests that the response to aggregation induced by native E. coli adhesins could have been finely tuned during bacterial evolution. Our study therefore provides insights into the effect of self-interaction in bacteria and allows a better understanding of why bacterial aggregates exhibit increased stress tolerance. IMPORTANCE The formation of bacterial aggregates has an important role in both clinical and ecological contexts. Although these structures have been previously shown to be more resistant to stressful conditions, the genetic basis of this stress tolerance associated with the aggregate lifestyle is poorly understood. Surface sensing mediated by different adhesins can result in various changes in bacterial physiology. However, whether adhesin-adhesin interactions, as well as the type of adhesin mediating aggregation, affect bacterial cell physiology is unknown. By sequencing the transcriptomes of aggregated and nonaggregated cells expressing native or synthetic adhesins, we characterized the effects of aggregation and adhesin type on E. coli physiology.
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Affiliation(s)
- Yankel Chekli
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Genetics of Biofilms Laboratory, Paris, France
| | - Rebecca J. Stevick
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Genetics of Biofilms Laboratory, Paris, France
| | - Etienne Kornobis
- Hub de Bioinformatique et Biostatistique-Département Biologie Computationnelle, Institut Pasteur, USR 3756 CNRS, Paris, France
- Plate-forme Technologique Biomics—Centre de Ressources et Recherches Technologiques, Institut Pasteur, Paris, France
| | - Valérie Briolat
- Hub de Bioinformatique et Biostatistique-Département Biologie Computationnelle, Institut Pasteur, USR 3756 CNRS, Paris, France
- Plate-forme Technologique Biomics—Centre de Ressources et Recherches Technologiques, Institut Pasteur, Paris, France
| | - Jean-Marc Ghigo
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Genetics of Biofilms Laboratory, Paris, France
| | - Christophe Beloin
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Genetics of Biofilms Laboratory, Paris, France
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Sano K, Kobayashi H, Chuta H, Matsuyoshi N, Kato Y, Ogasawara H. CsgI (YccT) Is a Novel Inhibitor of Curli Fimbriae Formation in Escherichia coli Preventing CsgA Polymerization and Curli Gene Expression. Int J Mol Sci 2023; 24:ijms24054357. [PMID: 36901788 PMCID: PMC10002515 DOI: 10.3390/ijms24054357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 02/25/2023] Open
Abstract
Curli fimbriae are amyloids-found in bacteria (Escherichia coli)-that are involved in solid-surface adhesion and bacterial aggregation during biofilm formation. The curli protein CsgA is coded by a csgBAC operon gene, and the transcription factor CsgD is essential to induce its curli protein expression. However, the complete mechanism underlying curli fimbriae formation requires elucidation. Herein, we noted that curli fimbriae formation was inhibited by yccT-i.e., a gene that encodes a periplasmic protein of unknown function regulated by CsgD. Furthermore, curli fimbriae formation was strongly repressed by CsgD overexpression caused by a multicopy plasmid in BW25113-the non-cellulose-producing strain. YccT deficiency prevented these CsgD effects. YccT overexpression led to intracellular YccT accumulation and reduced CsgA expression. These effects were addressed by deleting the N-terminal signal peptide of YccT. Localization, gene expression, and phenotypic analyses revealed that YccT-dependent inhibition of curli fimbriae formation and curli protein expression was mediated by the two-component regulatory system EnvZ/OmpR. Purified YccT inhibited CsgA polymerization; however, no intracytoplasmic interaction between YccT and CsgA was detected. Thus, YccT-renamed CsgI (curli synthesis inhibitor)-is a novel inhibitor of curli fimbriae formation and has a dual role as an OmpR phosphorylation modulator and CsgA polymerization inhibitor.
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Affiliation(s)
- Kotaro Sano
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Hiroaki Kobayashi
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Hirotaka Chuta
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Nozomi Matsuyoshi
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Yuki Kato
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Hiroshi Ogasawara
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Academic Assembly School of Humanities and Social Sciences Institute of Humanities, Shinshu University, Matsumoto 390-8621, Japan
- Institute for Fiber Engineering (IFES), Interdisciplinary Cluster for Cutting Edge Research (ICCER), Shinshu University, Tokida 3-15-1, Ueda, Nagano 386-8567, Japan
- Renaissance Center for Applied Microbiology, Shinshu University, Nagano-shi, Nagano 380-8553, Japan
- Correspondence: ; Tel.: +81-268-21-5803
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McLaughlin M, Hershey DM, Reyes Ruiz LM, Fiebig A, Crosson S. A cryptic transcription factor regulates Caulobacter adhesin development. PLoS Genet 2022; 18:e1010481. [PMID: 36315598 PMCID: PMC9648850 DOI: 10.1371/journal.pgen.1010481] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 11/10/2022] [Accepted: 10/18/2022] [Indexed: 11/07/2022] Open
Abstract
Alphaproteobacteria commonly produce an adhesin that is anchored to the exterior of the envelope at one cell pole. In Caulobacter crescentus this adhesin, known as the holdfast, facilitates attachment to solid surfaces and cell partitioning to air-liquid interfaces. An ensemble of two-component signal transduction (TCS) proteins controls C. crescentus holdfast biogenesis by indirectly regulating expression of HfiA, a potent inhibitor of holdfast synthesis. We performed a genetic selection to discover direct hfiA regulators that function downstream of the adhesion TCS system and identified rtrC, a hypothetical gene. rtrC transcription is directly activated by the adhesion TCS regulator, SpdR. Though its primary structure bears no resemblance to any defined protein family, RtrC binds and regulates dozens of sites on the C. crescentus chromosome via a pseudo-palindromic sequence. Among these binding sites is the hfiA promoter, where RtrC functions to directly repress transcription and thereby activate holdfast development. Either RtrC or SpdR can directly activate transcription of a second hfiA repressor, rtrB. Thus, environmental regulation of hfiA transcription by the adhesion TCS system is subject to control by an OR-gated type I coherent feedforward loop; these regulatory motifs are known to buffer gene expression against fluctuations in regulating signals. We have further assessed the functional role of rtrC in holdfast-dependent processes, including surface adherence to a cellulosic substrate and formation of pellicle biofilms at air-liquid interfaces. Strains harboring insertional mutations in rtrC have a diminished adhesion profile in a competitive cheesecloth binding assay and a reduced capacity to colonize pellicle biofilms in select media conditions. Our results add to an emerging understanding of the regulatory topology and molecular components of a complex bacterial cell adhesion control system.
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Affiliation(s)
- Maeve McLaughlin
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
| | - David M. Hershey
- Department of Bacteriology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Leila M. Reyes Ruiz
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Aretha Fiebig
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
| | - Sean Crosson
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
- * E-mail:
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Kamali Dolatabadi R, Fazeli H, Emami MH, Karbasizade V, Maghool F, Fahim A, Rahimi H. Phenotypicand Genotypic Characterization of Clinical Isolates of Intracellular Adherent–Invasive Escherichia coli Among Different Stages, Family History, and Treated Colorectal Cancer Patients in Iran. Front Cell Infect Microbiol 2022; 12:938477. [PMID: 35899040 PMCID: PMC9309365 DOI: 10.3389/fcimb.2022.938477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
There is increasing evidence showing that microbial dysbiosis impacts the health and cancer risk of the host. An association between adherent–invasive Escherichia coli (AIEC) and colorectal cancer (CRC) has been revealed. Cyclomodulins (CMs) have been receiving increasing attention for carcinogenic changes. In this study, the incidence and features of intracellular AIEC and cyclomodulin-encoding genes were investigated and the phylogenetic grouping and genetic relatedness were evaluated. E. coli strains were isolated from the colorectal biopsies. Adhesion and invasion assays and intramacrophage cell survival test were performed to separate the AIEC isolates. Virulence genotyping for the genes htrA, dsbA, chuA, and lpfA and the cyclomodulin toxins was also conducted. In addition, phylogenetic grouping of the isolates was determined. Subsequently, repetitive element sequence-based PCR (rep-PCR) fingerprinting was performed. A total of 24 AIEC pathovars were isolated from 150 patients. The prevalence rates of htr, dsbA, and lpfA were 70.83% and that of chuA was 91.66%. The frequencies of the cyclomodulin toxins were as follows: cnf1, 29.2%; cnf2, 25%; colibactin, 29.2%; and cdt, 4.2%; cif was not found. Among the AIEC isolates, 4.2%, 4.2%, 54.2%, 29.2%, and 8.3% with phylotypes A or C, B1, B2, D, and E were identified, respectively. Left-sided colon carcinoma and adenocarcinoma T≥1 stage (CRC2) were colonized by B2 phylogroup AIEC-producing CMs more often than the samples from the other groups. Close genetic relatedness was observed in AIEC isolates with rep-PCR.
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Affiliation(s)
- Razie Kamali Dolatabadi
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hossein Fazeli
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
- *Correspondence: Hossein Fazeli,
| | - Mohammad Hassan Emami
- Poursina Hakim Digestive Diseases Research center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Vajihe Karbasizade
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Fatemeh Maghool
- Poursina Hakim Digestive Diseases Research center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Alireza Fahim
- Poursina Hakim Digestive Diseases Research center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hojatollah Rahimi
- Poursina Hakim Digestive Diseases Research center, Isfahan University of Medical Sciences, Isfahan, Iran
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10
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Moran-Garcia N, Lopez-Saucedo C, Becerra A, Meza-Segura M, Hernandez-Cazares F, Guerrero-Baez J, Galindo-Gómez S, Tsutsumi V, Schnoor M, Méndez-Tenorio A, Nataro JP, Estrada-Garcia T. A Novel Adult Murine Model of Typical Enteroaggregative Escherichia coli Infection Reveals Microbiota Dysbiosis, Mucus Secretion, and AAF/II-Mediated Expression and Localization of β-Catenin and Expression of MUC1 in Ileum. Front Cell Infect Microbiol 2022; 12:885191. [PMID: 35706909 PMCID: PMC9190437 DOI: 10.3389/fcimb.2022.885191] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 04/22/2022] [Indexed: 11/13/2022] Open
Abstract
Typical enteroaggregative Escherichia coli (tEAEC) is a diarrheagenic E. coli pathotype associated with pediatric and traveler’s diarrhea. Even without diarrhea, EAEC infections in children also lead to increased gut inflammation and growth shortfalls. EAEC strain’s defining phenotype is the aggregative adherence pattern on epithelial cells attributable to the aggregative adherence fimbriae (AAF). EAEC only causes diarrhea in humans; therefore, not much is known of the exact intestinal region of infection and damage or its interactions with intestinal enterocytes in vivo and in situ. This study aimed to develop a new tEAEC mouse model of infection, characterize the microbiota of infected mice, and evaluate in situ the expression of host adherence and surface molecules triggering EAEC infection and the role of the EAEC AAF-II in adherence. Six-week-old C57BL/6 mice, without previous antibiotic treatment, were orally challenged with EAEC 042 strain or EAEC 042 AAF-II mutant (ΔAAF/II) strain, or DAEC-MXR strain (diffusely adherent E. coli clinical isolate), and with saline solution (control group). Paraffin sections of the colon and ileum were stained with H&E and periodic acid-Schiff. ZO-1, β-catenin, MUC1, and bacteria were analyzed by immunofluorescence. EAEC-infected mice, in comparison with DAEC-MXR-infected and control mice, significantly lost weight during the first 3 days. After 7 days post-infection, mucus production was increased in the colon and ileum, ZO-1 localization remained unaltered, and morphological alterations were more pronounced in the ileum since increased expression and apical localization of β-catenin in ileal enterocytes were observed. EAEC-infected mice developed dysbiosis 21 days post-infection. At 4 days post-infection, EAEC strain 042 formed a biofilm on ileal villi and increased the expression and apical localization of β-catenin in ileal enterocytes; these effects were not seen in animals infected with the 042 ΔAAF/II strain. At 3 days post-infection, MUC1 expression on ileal enterocytes was mainly detectable among infected mice and colocalized with 042 strains on the enterocyte surface. We developed a novel mouse model of EAEC infection, which mimics human infection, not an illness, revealing that EAEC 042 exerts its pathogenic effects in the mouse ileum and causes dysbiosis. This model is a unique tool to unveil early molecular mechanisms of EAEC infection in vivo and in situ.
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Affiliation(s)
| | | | - Adriana Becerra
- Department of Molecular Biomedicine, CINVESTAV-IPN, Mexico City, Mexico
| | - Mario Meza-Segura
- Department of Molecular Biomedicine, CINVESTAV-IPN, Mexico City, Mexico
| | | | | | - Silvia Galindo-Gómez
- Department of Infectomics and Molecular Pathogenesis, CINVESTAV-IPN, Mexico City, Mexico
| | - Víctor Tsutsumi
- Department of Infectomics and Molecular Pathogenesis, CINVESTAV-IPN, Mexico City, Mexico
| | - Michael Schnoor
- Department of Molecular Biomedicine, CINVESTAV-IPN, Mexico City, Mexico
| | - Alfonso Méndez-Tenorio
- Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - James P. Nataro
- Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Teresa Estrada-Garcia
- Department of Molecular Biomedicine, CINVESTAV-IPN, Mexico City, Mexico
- *Correspondence: Teresa Estrada-Garcia,
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11
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Tan X, Lin YP, Pereira MJ, Castellanos M, Hahn BL, Anderson P, Coburn J, Leong JM, Chaconas G. VlsE, the nexus for antigenic variation of the Lyme disease spirochete, also mediates early bacterial attachment to the host microvasculature under shear force. PLoS Pathog 2022; 18:e1010511. [PMID: 35605029 PMCID: PMC9166660 DOI: 10.1371/journal.ppat.1010511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/03/2022] [Accepted: 04/08/2022] [Indexed: 11/19/2022] Open
Abstract
Hematogenous dissemination is a critical step in the evolution of local infection to systemic disease. The Lyme disease (LD) spirochete, which efficiently disseminates to multiple tissues, has provided a model for this process, in particular for the key early event of pathogen adhesion to the host vasculature. This occurs under shear force mediated by interactions between bacterial adhesins and mammalian cell-surface proteins or extracellular matrix (ECM). Using real-time intravital imaging of the Lyme spirochete in living mice, we previously identified BBK32 as the first LD spirochetal adhesin demonstrated to mediate early vascular adhesion in a living mouse; however, deletion of bbk32 resulted in loss of only about half of the early interactions, suggesting the existence of at least one other adhesin (adhesin-X) that promotes early vascular interactions. VlsE, a surface lipoprotein, was identified long ago by its capacity to undergo rapid antigenic variation, is upregulated in the mammalian host and required for persistent infection in immunocompetent mice. In immunodeficient mice, VlsE shares functional overlap with OspC, a multi-functional protein that displays dermatan sulfate-binding activity and is required for joint invasion and colonization. In this research, using biochemical and genetic approaches as well as intravital imaging, we have identified VlsE as adhesin-X; it is a dermatan sulfate (DS) adhesin that efficiently promotes transient adhesion to the microvasculature under shear force via its DS binding pocket. Intravenous inoculation of mice with a low-passage infectious B. burgdorferi strain lacking both bbk32 and vlsE almost completely eliminated transient microvascular interactions. Comparative analysis of binding parameters of VlsE, BBK32 and OspC provides a possible explanation why these three DS adhesins display different functionality in terms of their ability to promote early microvascular interactions.
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Affiliation(s)
- Xi Tan
- Department of Biochemistry & Molecular Biology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Yi-Pin Lin
- Division of Infectious Diseases, New York State Department of Health, Wadsworth Center, Albany, New York, United States of America
| | - Michael J. Pereira
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Mildred Castellanos
- Department of Biochemistry & Molecular Biology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Beth L. Hahn
- Department of Medicine, Division of Infectious Diseases, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Phillip Anderson
- Department of Medicine, Division of Infectious Diseases, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Jenifer Coburn
- Department of Medicine, Division of Infectious Diseases, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - John M. Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - George Chaconas
- Departments of Biochemistry & Molecular Biology and Microbiology, Immunology & Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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12
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Ozanic M, Marecic V, Knezevic M, Kelava I, Stojková P, Lindgren L, Bröms JE, Sjöstedt A, Abu Kwaik Y, Santic M. The type IV pili component PilO is a virulence determinant of Francisella novicida. PLoS One 2022; 17:e0261938. [PMID: 35077486 PMCID: PMC8789160 DOI: 10.1371/journal.pone.0261938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 12/14/2021] [Indexed: 12/03/2022] Open
Abstract
Francisella tularensis is a highly pathogenic intracellular bacterium that causes the disease tularemia. While its ability to replicate within cells has been studied in much detail, the bacterium also encodes a less characterised type 4 pili (T4P) system. T4Ps are dynamic adhesive organelles identified as major virulence determinants in many human pathogens. In F. tularensis, the T4P is required for adherence to the host cell, as well as for protein secretion. Several components, including pilins, a pili peptidase, a secretin pore and two ATPases, are required to assemble a functional T4P, and these are encoded within distinct clusters on the Francisella chromosome. While some of these components have been functionally characterised, the role of PilO, if any, still is unknown. Here, we examined the role of PilO in the pathogenesis of F. novicida. Our results show that the PilO is essential for pilus assembly on the bacterial surface. In addition, PilO is important for adherence of F. novicida to human monocyte-derived macrophages, secretion of effector proteins and intracellular replication. Importantly, the pilO mutant is attenuated for virulence in BALB/c mice regardless of the route of infection. Following intratracheal and intradermal infection, the mutant caused no histopathology changes, and demonstrated impaired phagosomal escape and replication within lung liver as well as spleen. Thus, PilO is an essential virulence determinant of F. novicida.
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Affiliation(s)
- Mateja Ozanic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Valentina Marecic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Masa Knezevic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Ina Kelava
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Pavla Stojková
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Lena Lindgren
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Jeanette E. Bröms
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Anders Sjöstedt
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Yousef Abu Kwaik
- Department of Microbiology and Immunology and Center for Predictive Medicine, College of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Marina Santic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
- * E-mail:
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13
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Nijjer J, Li C, Zhang Q, Lu H, Zhang S, Yan J. Mechanical forces drive a reorientation cascade leading to biofilm self-patterning. Nat Commun 2021; 12:6632. [PMID: 34789754 PMCID: PMC8599862 DOI: 10.1038/s41467-021-26869-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 10/26/2021] [Indexed: 01/12/2023] Open
Abstract
In growing active matter systems, a large collection of engineered or living autonomous units metabolize free energy and create order at different length scales as they proliferate and migrate collectively. One such example is bacterial biofilms, surface-attached aggregates of bacterial cells embedded in an extracellular matrix that can exhibit community-scale orientational order. However, how bacterial growth coordinates with cell-surface interactions to create distinctive, long-range order during biofilm development remains elusive. Here we report a collective cell reorientation cascade in growing Vibrio cholerae biofilms that leads to a differentially ordered, spatiotemporally coupled core-rim structure reminiscent of a blooming aster. Cell verticalization in the core leads to a pattern of differential growth that drives radial alignment of the cells in the rim, while the growing rim generates compressive stresses that expand the verticalized core. Such self-patterning disappears in nonadherent mutants but can be restored through opto-manipulation of growth. Agent-based simulations and two-phase active nematic modeling jointly reveal the strong interdependence of the driving forces underlying the differential ordering. Our findings offer insight into the developmental processes that shape bacterial communities and provide ways to engineer phenotypes and functions in living active matter.
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Affiliation(s)
- Japinder Nijjer
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Changhao Li
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA, USA
| | - Qiuting Zhang
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Haoran Lu
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Sulin Zhang
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA, USA.
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA.
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
- Quantitative Biology Institute, Yale University, New Haven, CT, USA.
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14
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Cho H, Masters T, Greenwood‐Quaintance KE, Johnson S, Jeraldo PR, Chia N, Pu M, Abdel MP, Patel R. Transcriptomic analysis of Streptococcus agalactiae periprosthetic joint infection. Microbiologyopen 2021; 10:e1256. [PMID: 34964296 PMCID: PMC8678771 DOI: 10.1002/mbo3.1256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 09/09/2021] [Accepted: 11/22/2021] [Indexed: 11/08/2022] Open
Abstract
Although Streptococcus agalactiae periprosthetic joint infection (PJI) is not as prevalent as staphylococcal PJI, invasive S. agalactiae infection is not uncommon. Here, RNA-seq was used to perform transcriptomic analysis of S. agalactiae PJI using fluid derived from sonication of explanted arthroplasties of subjects with S. agalactiae PJI, with results compared to those of S. agalactiae strain NEM316 grown in vitro. A total of 227 genes with outlier expression were found (164 upregulated and 63 downregulated) between PJI sonicate fluid and in vitro conditions. Functional enrichment analysis showed genes involved in mobilome and inorganic ion transport and metabolism to be most enriched. Genes involved in nickel, copper, and zinc transport, were upregulated. Among known virulence factors, cyl operon genes, encoding β-hemolysin/cytolysin, were consistently highly expressed in PJI versus in vitro. The data presented provide insight into S. agalactiae PJI pathogenesis and may be a resource for identification of novel PJI therapeutics or vaccines against invasive S. agalactiae infections.
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Affiliation(s)
- Hye‐Kyung Cho
- Division of Clinical Microbiology, Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
| | - Thao Masters
- Division of Clinical Microbiology, Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
| | | | - Stephen Johnson
- Department of Health Sciences ResearchMayo ClinicRochesterMinnesotaUSA
| | - Patricio R. Jeraldo
- Center for Individualized MedicineMayo ClinicRochesterMinnesotaUSA
- Department of SurgeryMayo ClinicRochesterMinnesotaUSA
| | - Nicholas Chia
- Center for Individualized MedicineMayo ClinicRochesterMinnesotaUSA
- Department of SurgeryMayo ClinicRochesterMinnesotaUSA
| | - Meng Pu
- Department of Medicine, Division of Gastroenterology and HepatologyMayo ClinicRochesterMinnesotaUSA
| | - Matthew P. Abdel
- Department of Orthopedic SurgeryMayo ClinicRochesterMinnesotaUSA
| | - Robin Patel
- Division of Clinical Microbiology, Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
- Division of Infectious Diseases, Department of MedicineMayo ClinicRochesterMinnesotaUSA
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15
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Pentz JT, Lind PA. Forecasting of phenotypic and genetic outcomes of experimental evolution in Pseudomonas protegens. PLoS Genet 2021; 17:e1009722. [PMID: 34351900 PMCID: PMC8370652 DOI: 10.1371/journal.pgen.1009722] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 08/17/2021] [Accepted: 07/16/2021] [Indexed: 11/18/2022] Open
Abstract
Experimental evolution with microbes is often highly repeatable under identical conditions, suggesting the possibility to predict short-term evolution. However, it is not clear to what degree evolutionary forecasts can be extended to related species in non-identical environments, which would allow testing of general predictive models and fundamental biological assumptions. To develop an extended model system for evolutionary forecasting, we used previous data and models of the genotype-to-phenotype map from the wrinkly spreader system in Pseudomonas fluorescens SBW25 to make predictions of evolutionary outcomes on different biological levels for Pseudomonas protegens Pf-5. In addition to sequence divergence (78% amino acid and 81% nucleotide identity) for the genes targeted by mutations, these species also differ in the inability of Pf-5 to make cellulose, which is the main structural basis for the adaptive phenotype in SBW25. The experimental conditions were changed compared to the SBW25 system to test if forecasts were extendable to a non-identical environment. Forty-three mutants with increased ability to colonize the air-liquid interface were isolated, and the majority had reduced motility and was partly dependent on the Pel exopolysaccharide as a structural component. Most (38/43) mutations are expected to disrupt negative regulation of the same three diguanylate cyclases as in SBW25, with a smaller number of mutations in promoter regions, including an uncharacterized polysaccharide synthase operon. A mathematical model developed for SBW25 predicted the order of the three main pathways and the genes targeted by mutations, but differences in fitness between mutants and mutational biases also appear to influence outcomes. Mutated regions in proteins could be predicted in most cases (16/22), but parallelism at the nucleotide level was low and mutational hot spot sites were not conserved. This study demonstrates the potential of short-term evolutionary forecasting in experimental populations and provides testable predictions for evolutionary outcomes in other Pseudomonas species.
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Affiliation(s)
| | - Peter A. Lind
- Department of Molecular Biology, Umeå University, Umeå, Sweden
- * E-mail:
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16
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Li Q, Hu Y, Fei X, Du Y, Guo W, Chu D, Wang X, Wang S, Shi H. OmpC, a novel factor H-binding surface protein, is dispensable for the adherence and virulence of Salmonella enterica serovar Typhimurium. Vet Microbiol 2021; 259:109157. [PMID: 34197978 DOI: 10.1016/j.vetmic.2021.109157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 06/15/2021] [Indexed: 11/24/2022]
Abstract
Salmonella enterica serovar Typhimurium utilizes a series of strategies to evade host innate immune defenses, including the serum complement system. Many microbial pathogens have evolved the ability to bind the complement regulatory protein factor H (FH) through their surface factor H-binding proteins (FHBPs) to circumvent the complement-mediated bactericidal effect. However, the roles of FHBPs in Salmonella pathogenesis are not well understood. In this study, we demonstrated that the survival of S. Typhimurium in human serum was decreased in a time and concentration dependent manner. Pre-incubation with FH attenuated the sensitivity of S. Typhimurium strain χ3761 to complement-mediated serum killing, suggesting FH binding enhance survival in serum. We aimed to identify novel S. Typhimurium FHBPs and characterize their biological functions. Here, six potential FHBPs were identified by two-dimensional (2D)-Far-western blot, and three of them were further confirmed to bind FH by Far-western blot and dot blot. We found that deletion of ompC (ΔompC) significantly inhibited the survival of S. Typhimurium strain χ3761 in human serum. Our results indicated that the ompC mutation does not affect χ3761 adhesion to HeLa cells. Furthermore, a mice infection model showed that deletion of ompC had no significant effect on the histopathological lesions or viability compared with the wild-type strain χ3761. In summary, these results suggested that OmpC is an important FHBP, but not a critical virulence factor of S. Typhimurium.
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Affiliation(s)
- Quan Li
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, Jiangsu, China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.
| | - Yuhan Hu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, Jiangsu, China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.
| | - Xia Fei
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, Jiangsu, China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.
| | - Yuanzhao Du
- Yebio Bioengineering Co., Ltd of Qingdao, Qingdao, 266114, China.
| | - Weiwei Guo
- Yebio Bioengineering Co., Ltd of Qingdao, Qingdao, 266114, China.
| | - Dianfeng Chu
- Yebio Bioengineering Co., Ltd of Qingdao, Qingdao, 266114, China.
| | - Xiaobo Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, Jiangsu, China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.
| | - Shifeng Wang
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611-0880, USA.
| | - Huoying Shi
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, Jiangsu, China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China; Key Laboratory of Animal Infectious Diseases, Ministry of Agriculture, Yangzhou University, China; Jiangsu Key Laboratory of Preventive Veterinary Medicine, Yangzhou University, China.
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17
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Abstract
Autoaggregation, adherence between identical bacterial cells, is important for colonization, kin and kind recognition, and survival of bacteria. It is directly mediated by specific interactions between proteins or organelles on the surfaces of interacting cells or indirectly by the presence of secreted macromolecules such as eDNA and exopolysaccharides. Some autoaggregation effectors are self-associating and present interesting paradigms for protein interaction. Autoaggregation can be beneficial or deleterious at specific times and niches. It is, therefore, typically regulated through transcriptional or post-transcriptional mechanisms or epigenetically by phase variation. Autoaggregation can contribute to bacterial adherence, biofilm formation or other higher-level functions. However, autoaggregation is only required for these phenotypes in some bacteria. Thus, autoaggregation should be detected, studied and measured independently using both qualitative and quantitative in vitro and ex vivo methods. If better understood, autoaggregation holds the potential for the discovery of new therapeutic targets that could be cost-effectively exploited.
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Affiliation(s)
- El-shama Q. A. Nwoko
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Iruka N. Okeke
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Ibadan, Ibadan, Oyo State, Nigeria
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18
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Li Y, Li X, Hao Y, Liu Y, Dong Z, Li K. Biological and Physiochemical Methods of Biofilm Adhesion Resistance Control of Medical-Context Surface. Int J Biol Sci 2021; 17:1769-1781. [PMID: 33994861 PMCID: PMC8120469 DOI: 10.7150/ijbs.59025] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 04/01/2021] [Indexed: 12/12/2022] Open
Abstract
The formation of biofilms on medical-context surfaces gives the EPS embedded bacterial community protection and additional advantages that planktonic cells would not have such as increased antibiotic resistance and horizontal gene transfer. Bacterial cells tend to attach to a conditioning layer after overcoming possible electrical barriers and go through two phases of attachments: reversible and irreversible. In the first, bacterial attachment to the surface is reversible and occurs quickly whilst the latter is permanent and takes place over a longer period of time. Upon reaching a certain density in the bacterial community, quorum sensing causes phenotypical changes leading to a loss in motility and the production of EPS. This position paper seeks to address the problem of bacterial adhesion and biofilm formation for the medical surfaces by comparing inhabiting physicochemical interactions and biological mechanisms. Several physiochemical methodologies (e.g. ultrasonication, alternating magnetic field and chemical surface coating) and utilizing biological mechanisms (e.g. quorum quenching and EPS degrading enzymes) were suggested. The possible strategical applications of each category were suggested and evaluated to a balanced position to possibly eliminate the adhesion and formation of biofilms on medical-context surfaces.
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Affiliation(s)
- Yuanzhe Li
- School of Materials Science & Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Xiang Li
- School of Chemistry and Biomolecules Engineering, National University of Singapore, Singapore, 637551, Singapore
| | - Yu Hao
- School of Chemistry and Biomolecules Engineering, National University of Singapore, Singapore, 637551, Singapore
| | - Yang Liu
- School of Materials Science & Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- School of Mechanical Engineering, Xiangtan University, Xiangtan, 411105, China
| | - ZhiLi Dong
- School of Materials Science & Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Kexin Li
- Hwa Chong International School, Singapore, 269783, Singapore
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19
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Elhenawy W, Hordienko S, Gould S, Oberc AM, Tsai CN, Hubbard TP, Waldor MK, Coombes BK. High-throughput fitness screening and transcriptomics identify a role for a type IV secretion system in the pathogenesis of Crohn's disease-associated Escherichia coli. Nat Commun 2021; 12:2032. [PMID: 33795670 PMCID: PMC8016931 DOI: 10.1038/s41467-021-22306-w] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 03/05/2021] [Indexed: 02/06/2023] Open
Abstract
Adherent-invasive Escherichia coli (AIEC) are pathogenic bacteria frequently isolated from patients who have Crohn's disease (CD). Despite the phenotypic differences between AIEC and commensal E. coli, comparative genomic approaches have been unable to differentiate these two groups, making the identification of key virulence factors a challenge. Here, we conduct a high-resolution, in vivo genetic screen to map AIEC genes required for intestinal colonization of mice. In addition, we use in vivo RNA-sequencing to define the host-associated AIEC transcriptome. We identify diverse metabolic pathways required for efficient gut colonization by AIEC and show that a type IV secretion system (T4SS) is required to form biofilms on the surface of epithelial cells, thereby promoting AIEC persistence in the gut. E. coli isolated from CD patients are enriched for a T4SS, suggesting a possible connection to disease activity. Our findings establish the T4SS as a principal AIEC colonization factor and highlight the use of genome-wide screens in decoding the infection biology of CD-associated bacteria that otherwise lack a defined genetic signature.
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Affiliation(s)
- Wael Elhenawy
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, Hamilton, ON, Canada
| | - Sarah Hordienko
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada
| | - Steven Gould
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada
| | - Alexander M Oberc
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada
| | - Caressa N Tsai
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada
| | - Troy P Hubbard
- Division of Infectious Diseases, Brigham & Women's Hospital, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Matthew K Waldor
- Division of Infectious Diseases, Brigham & Women's Hospital, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
- Howard Hughes Medical Institute, Boston, MA, USA
| | - Brian K Coombes
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada.
- Michael G. DeGroote Institute for Infectious Disease Research, Hamilton, ON, Canada.
- Farncombe Family Digestive Health Research Institute, Hamilton, ON, Canada.
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20
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Gil-Marqués ML, Labrador Herrera G, Miró Canturri A, Pachón J, Smani Y, Pachón-Ibáñez ME. Role of PstS in the Pathogenesis of Acinetobacter baumannii Under Microaerobiosis and Normoxia. J Infect Dis 2021; 222:1204-1212. [PMID: 32324853 DOI: 10.1093/infdis/jiaa201] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 04/20/2020] [Indexed: 01/15/2023] Open
Abstract
Acinetobacter baumannii is a successful pathogen responsible for infections with high mortality rate. During the course of infection it can be found in microaerobic environments, which influences virulence factor expression. From a previous transcriptomic analysis of A. baumannii ATCC 17978 under microaerobiosis, we know the gene pstS is overexpressed under microaerobiosis. Here, we studied its role in A. baumannii virulence. pstS loss significantly decreased bacterial adherence and invasion into A549 cells and increased A549 cell viability. pstS loss also reduced motility and biofilm-forming ability of A. baumannii. In a peritoneal sepsis murine model, the minimum lethal dose required by A. baumannii ATCC 17978 ΔpstS was lower compared to the wild type (4.3 vs 3.2 log colony forming units/mL, respectively), and the bacterial burden in tissues and fluids was lower. Thus, the loss of the phosphate sensor PstS produced a decrease in A. baumannii pathogenesis, supporting its role as a virulence factor.
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Affiliation(s)
- María Luisa Gil-Marqués
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - Gema Labrador Herrera
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - Andrea Miró Canturri
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - Jerónimo Pachón
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
- Department of Medicine, University of Seville, Seville, Spain
| | - Younes Smani
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - María Eugenia Pachón-Ibáñez
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
- Department of Medicine, University of Seville, Seville, Spain
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21
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Abstract
Fimbriae of the periodontal pathogen Porphyromonas gingivalis mediate its colonization through associations with other bacteria and host tissues. P. gingivalis generally expresses two distinct fimbrial types, FimA and Mfa1. In P. gingivalis ATCC 33277, FimA fimbriae are present as long filaments easily detached from cells, whereas Mfa1 fimbriae are short filaments compactly bound to the cell surface. Because of this unique characteristic, FimA fimbriae have been selectively and easily isolated from the bacterial cell surface through mechanical shearing such as by pipetting and stirring. However, P. gingivalis ATCC 33277 harbors a mutation in the gene encode the fimbrial length regulator, FimB, and thus produces unusually long FimA fimbriae length. Hence, mechanical shearing to remove FimA is potentially applicable only for this type strain. Here we present protocols to purify intact Mfa1 fimbriae from a fimA-deficient mutant strain. Mfa1 fimbriae are purified from cell lysates, using a French pressure cell and through ion-exchange chromatography. The purity of Mfa1 fimbriae can be confirmed through sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting, and electron microscopy.
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Affiliation(s)
- Yoshiaki Hasegawa
- Department of Microbiology, School of Dentistry, Aichi Gakuin University, Nisshin, Aichi, Japan.
| | - Keiji Nagano
- Division of Microbiology, Department of Oral Biology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido, Japan
| | - Yukitaka Murakami
- Department of Dental Basic Education (Biology), Asahi University School of Dentistry, Mizuho, Gifu, Japan
| | - Richard J Lamont
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, KY, USA
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22
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Drolia R, Amalaradjou MAR, Ryan V, Tenguria S, Liu D, Bai X, Xu L, Singh AK, Cox AD, Bernal-Crespo V, Schaber JA, Applegate BM, Vemulapalli R, Bhunia AK. Receptor-targeted engineered probiotics mitigate lethal Listeria infection. Nat Commun 2020; 11:6344. [PMID: 33311493 PMCID: PMC7732855 DOI: 10.1038/s41467-020-20200-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 11/18/2020] [Indexed: 12/24/2022] Open
Abstract
Probiotic bacteria reduce the intestinal colonization of pathogens. Yet, their use in preventing fatal infection caused by foodborne Listeria monocytogenes (Lm), is inconsistent. Here, we bioengineered Lactobacillus probiotics (BLP) to express the Listeria adhesion protein (LAP) from a non-pathogenic Listeria (L. innocua) and a pathogenic Listeria (Lm) on the surface of Lactobacillus casei. The BLP strains colonize the intestine, reduce Lm mucosal colonization and systemic dissemination, and protect mice from lethal infection. The BLP competitively excludes Lm by occupying the surface presented LAP receptor, heat shock protein 60 and ameliorates the Lm-induced intestinal barrier dysfunction by blocking the nuclear factor-κB and myosin light chain kinase-mediated redistribution of the major epithelial junctional proteins. Additionally, the BLP increases intestinal immunomodulatory functions by recruiting FOXP3+T cells, CD11c+ dendritic cells and natural killer cells. Engineering a probiotic strain with an adhesion protein from a non-pathogenic bacterium provides a new paradigm to exclude pathogens and amplify their inherent health benefits.
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Affiliation(s)
- Rishi Drolia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
- Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - Mary Anne Roshni Amalaradjou
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
- Department of Animal Science, University of Connecticut, Storrs, CT, USA
| | - Valerie Ryan
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
| | - Shivendra Tenguria
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
- Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - Dongqi Liu
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
- Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - Xingjian Bai
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
| | - Luping Xu
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
| | - Atul K Singh
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
| | - Abigail D Cox
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN, USA
| | - Victor Bernal-Crespo
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN, USA
| | - James A Schaber
- Bindley Bioscience Research Center, Purdue University, West Lafayette, IN, USA
| | - Bruce M Applegate
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA
- Purdue University Interdisciplinary Life Science Program, Purdue University, West Lafayette, IN, USA
| | - Ramesh Vemulapalli
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN, USA
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX, USA
| | - Arun K Bhunia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, USA.
- Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA.
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN, USA.
- Purdue University Interdisciplinary Life Science Program, Purdue University, West Lafayette, IN, USA.
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23
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Yu Z, Wang E, Geng Y, Wang K, Chen D, Huang X, Ouyang P, Zuo Z, Huang C, Fang J, Yin L, Guo H, Zhong Z. Complete genome analysis of Vibrio mimicus strain SCCF01, a highly virulent isolate from the freshwater catfish. Virulence 2020; 11:23-31. [PMID: 31826705 PMCID: PMC6961728 DOI: 10.1080/21505594.2019.1702797] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 10/14/2019] [Accepted: 10/14/2019] [Indexed: 12/02/2022] Open
Abstract
Vibrio mimicus is a foodborne pathogen, which is widely distributed in the aquatic environment. Moreover, it is often involved in aquatic animal diseases. In recent years, V. mimicus is an emerging pathogen in some species of Siluriformes. The strain SCCF01 was isolated from yellow catfish (Pelteobagrus fulvidraco). In this study, we aimed to perform genomic analysis of V. mimicus strain SCCF01 to identify genetic features and evolutionary relationships. Information on gene function and classification was obtained by functional annotation, and circular graph of strain SCCF01 genome, which was created by Circos v0.64. Information on virulence genes (adhesion, flagellum system, exotoxin, and secretory system, etc.) was obtained by virulence genes annotation. Genome element prediction showed that most of the mobile elements were distributed in chromosome I. Therefore, chromosome I of SCCF01 genome has more plasticity than chromosome II and might be larger in size. Genomic linear relationship between the strain of V. mimicus and strain SCCF01 was analyzed by linear pairwise comparison but was unable to determine the relationship. Gene family analysis predicted that the evolutionary direction of strain SCCF01 was: clinical strain → environmental strain → SCCF01 strain. Phylogenetic analysis showed that the strain SCCF01 was more closely related to environmental strains. According to gene family analysis and phylogenetic analysis, we speculated that strain SCCF01 has probably diverged from environmental strains.
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Affiliation(s)
- Zehui Yu
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
- Laboratory Animal Center, Southwest Medical University, LuZhou, Sichuan, P. R. China
| | - Erlong Wang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Yi Geng
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Kaiyu Wang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Defang Chen
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Xiaoli Huang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Ping Ouyang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Zhicai Zuo
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Chao Huang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Jing Fang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Lizi Yin
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Hongrui Guo
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
| | - Zhijun Zhong
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, P. R. China
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24
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Ali A, Kolenda R, Khan MM, Weinreich J, Li G, Wieler LH, Tedin K, Roggenbuck D, Schierack P. Novel Avian Pathogenic Escherichia coli Genes Responsible for Adhesion to Chicken and Human Cell Lines. Appl Environ Microbiol 2020; 86:e01068-20. [PMID: 32769194 PMCID: PMC7531953 DOI: 10.1128/aem.01068-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 08/02/2020] [Indexed: 12/13/2022] Open
Abstract
Avian pathogenic Escherichia coli (APEC) is a major bacterial pathogen of commercial poultry contributing to extensive economic losses and contamination of the food chain. One of the initial steps in bacterial infection and successful colonization of the host is adhesion to the host cells. A random transposon mutant library (n = 1,300) of APEC IMT 5155 was screened phenotypically for adhesion to chicken (CHIC-8E11) and human (LoVo) intestinal epithelial cell lines. The detection and quantification of adherent bacteria were performed by a modified APEC-specific antibody staining assay using fluorescence microscopy coupled to automated VideoScan technology. Eleven mutants were found to have significantly altered adhesion to the cell lines examined. Mutated genes in these 11 "adhesion-altered mutants" were identified by arbitrary PCR and DNA sequencing. The genes were amplified from wild-type APEC IMT 5155, cloned, and transformed into the respective adhesion-altered mutants, and complementation was determined in adhesion assays. Here, we report contributions of the fdtA, rluD, yjhB, ecpR, and fdeC genes of APEC in adhesion to chicken and human intestinal cell lines. Identification of the roles of these genes in APEC pathogenesis will contribute to prevention and control of APEC infections.IMPORTANCE Avian pathogenic E. coli is not only pathogenic for commercial poultry but can also cause foodborne infections in humans utilizing the same attachment and virulence mechanisms. Our aim was to identify genes of avian pathogenic E. coli involved in adhesion to chicken and human cells in order to understand the colonization and pathogenesis of these bacteria. In contrast to the recent studies based on genotypic and bioinformatics data, we have used a combination of phenotypic and genotypic approaches for identification of novel genes contributing to adhesion in chicken and human cell lines. Identification of adhesion factors remains important, as antibodies elicited against such factors have shown potential to block colonization and ultimately prevent disease as prophylactic vaccines. Therefore, the data will augment the understanding of disease pathogenesis and ultimately in designing strategies against the infections.
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Affiliation(s)
- Aamir Ali
- National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Faisalabad, Pakistan
- Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Rafał Kolenda
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Muhammad Moman Khan
- Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Jörg Weinreich
- Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Ganwu Li
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | | | - Karsten Tedin
- Institute for Microbiology and Epizootics, Free University of Berlin, Berlin, Germany
| | - Dirk Roggenbuck
- Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus-Senftenberg, the Brandenburg Medical School Theodor Fontane and the University of Potsdam, Potsdam, Germany
| | - Peter Schierack
- Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus-Senftenberg, the Brandenburg Medical School Theodor Fontane and the University of Potsdam, Potsdam, Germany
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25
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Mancini NL, Rajeev S, Jayme TS, Wang A, Keita ÅV, Workentine ML, Hamed S, Söderholm JD, Lopes F, Shutt TE, Shearer J, McKay DM. Crohn's Disease Pathobiont Adherent-Invasive E coli Disrupts Epithelial Mitochondrial Networks With Implications for Gut Permeability. Cell Mol Gastroenterol Hepatol 2020; 11:551-571. [PMID: 32992049 PMCID: PMC7797367 DOI: 10.1016/j.jcmgh.2020.09.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Adherent-invasive Escherichia coli are implicated in inflammatory bowel disease, and mitochondrial dysfunction has been observed in biopsy specimens from patients with inflammatory bowel disease. As a novel aspect of adherent-invasive E coli-epithelial interaction, we hypothesized that E coli (strain LF82) would elicit substantial disruption of epithelial mitochondrial form and function. METHODS Monolayers of human colon-derived epithelial cell lines were exposed to E coli-LF82 or commensal E coli and RNA sequence analysis, mitochondrial function (adenosine triphosphate synthesis) and dynamics (mitochondrial network imaging, immunoblotting for fission and fusion proteins), and epithelial permeability (transepithelial resistance, flux of fluorescein isothiocyanate-dextran and bacteria) were assessed. RESULTS E coli-LF82 significantly affected epithelial expression of ∼8600 genes, many relating to mitochondrial function. E coli-LF82-infected epithelia showed swollen mitochondria, reduced mitochondrial membrane potential and adenosine triphosphate, and fragmentation of the mitochondrial network: events not observed with dead E coli-LF82, medium from bacterial cultures, or control E coli. Treatment with Mitochondrial Division Inhibitor 1 (Mdivi1, inhibits dynamin-related peptide 1, guanosine triphosphatase principally responsible for mitochondrial fission) or P110 (prevents dynamin-related peptide 1 binding to mitochondrial fission 1 protein) partially reduced E coli-LF82-induced mitochondrial fragmentation in the short term. E coli-LF82-infected epithelia showed loss of the long isoform of optic atrophy factor 1, which mediates mitochondrial fusion. Mitochondrial Division Inhibitor 1 reduced the magnitude of E coli-LF82-induced increased transepithelial flux of fluorescein isothiocyanate dextran. By 8 hours after infection, increased cytosolic cytochrome C and DNA fragmentation were apparent without evidence of caspase-3 or apoptosis inducing factor activation. CONCLUSIONS Epithelial mitochondrial fragmentation caused by E coli-LF82 could be targeted to maintain cellular homeostasis and mitigate infection-induced loss of epithelial barrier function. Data have been deposited in NCBI's Gene Expression Omnibus and are accessible through GEO series accession numbers GSE154121 and GSE154122 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE154121).
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Affiliation(s)
- Nicole L Mancini
- Gastrointestinal Research Group and Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Joan and Phoebe Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Sruthi Rajeev
- Gastrointestinal Research Group and Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Joan and Phoebe Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Timothy S Jayme
- Gastrointestinal Research Group and Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Joan and Phoebe Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Arthur Wang
- Gastrointestinal Research Group and Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Joan and Phoebe Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Åsa V Keita
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | | | - Samira Hamed
- Gastrointestinal Research Group and Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Joan and Phoebe Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Johan D Söderholm
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden; Department of Surgery, County Council of Östergötland, Linköping, Sweden
| | - Fernando Lopes
- Institute of Parasitology, Faculty of Agriculture and Environmental Sciences, Department of Microbiology and Immunology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Timothy E Shutt
- Department of Medical Genetics, Alberta Children's Hospital Research Institute, University of Calgary, Alberta, Canada
| | - Jane Shearer
- Department of Biochemistry and Molecular Biology, Faculty of Kinesiology, University of Calgary, Alberta, Canada
| | - Derek M McKay
- Gastrointestinal Research Group and Inflammation Research Network, Department of Physiology and Pharmacology, Calvin, Joan and Phoebe Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada.
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26
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Alhajjar N, Chatterjee A, Spencer BL, Burcham LR, Willett JLE, Dunny GM, Duerkop BA, Doran KS. Genome-Wide Mutagenesis Identifies Factors Involved in Enterococcus faecalis Vaginal Adherence and Persistence. Infect Immun 2020; 88:e00270-20. [PMID: 32778611 PMCID: PMC7504943 DOI: 10.1128/iai.00270-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 07/26/2020] [Indexed: 02/08/2023] Open
Abstract
Enterococcus faecalis is a Gram-positive commensal bacterium native to the gastrointestinal tract and an opportunistic pathogen of increasing clinical concern. E. faecalis also colonizes the female reproductive tract, and reports suggest vaginal colonization increases following antibiotic treatment or in patients with aerobic vaginitis. Currently, little is known about specific factors that promote E. faecalis vaginal colonization and subsequent infection. We modified an established mouse vaginal colonization model to explore E. faecalis vaginal carriage and demonstrate that both vancomycin-resistant and -sensitive strains colonize the murine vaginal tract. Following vaginal colonization, we observed E. faecalis in vaginal, cervical, and uterine tissue. A mutant lacking endocarditis- and biofilm-associated pili (Ebp) exhibited a decreased ability to associate with human vaginal and cervical cells in vitro but did not contribute to colonization in vivo Thus, we screened a low-complexity transposon (Tn) mutant library to identify novel genes important for E. faecalis colonization and persistence in the vaginal tract. This screen revealed 383 mutants that were underrepresented during vaginal colonization at 1, 5, and 8 days postinoculation compared to growth in culture medium. We confirmed that mutants deficient in ethanolamine catabolism or in the type VII secretion system were attenuated in persisting during vaginal colonization. These results reveal the complex nature of vaginal colonization and suggest that multiple factors contribute to E. faecalis persistence in the reproductive tract.
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Affiliation(s)
- Norhan Alhajjar
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Anushila Chatterjee
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Brady L Spencer
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Lindsey R Burcham
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Julia L E Willett
- Department of Microbiology and Immunology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Gary M Dunny
- Department of Microbiology and Immunology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Breck A Duerkop
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Kelly S Doran
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
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Boisen N, Østerlund MT, Joensen KG, Santiago AE, Mandomando I, Cravioto A, Chattaway MA, Gonyar LA, Overballe-Petersen S, Stine OC, Rasko DA, Scheutz F, Nataro JP. Redefining enteroaggregative Escherichia coli (EAEC): Genomic characterization of epidemiological EAEC strains. PLoS Negl Trop Dis 2020; 14:e0008613. [PMID: 32898134 PMCID: PMC7500659 DOI: 10.1371/journal.pntd.0008613] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 09/18/2020] [Accepted: 07/20/2020] [Indexed: 11/19/2022] Open
Abstract
Although enteroaggregative E. coli (EAEC) has been implicated as a common cause of diarrhea in multiple settings, neither its essential genomic nature nor its role as an enteric pathogen are fully understood. The current definition of this pathotype requires demonstration of cellular adherence; a working molecular definition encompasses E. coli which do not harbor the heat-stable or heat-labile toxins of enterotoxigenic E. coli (ETEC) and harbor the genes aaiC, aggR, and/or aatA. In an effort to improve the definition of this pathotype, we report the most definitive characterization of the pan-genome of EAEC to date, applying comparative genomics and functional characterization on a collection of 97 EAEC strains isolated in the course of a multicenter case-control diarrhea study (Global Enteric Multi-Center Study, GEMS). Genomic analysis revealed that the EAEC strains mapped to all phylogenomic groups of E. coli. Circa 70% of strains harbored one of the five described AAF variants; there were no additional AAF variants identified, and strains that lacked an identifiable AAF generally did not have an otherwise complete AggR regulon. An exception was strains that harbored an ETEC colonization factor (CF) CS22, like AAF a member of the chaperone-usher family of adhesins, but not phylogenetically related to the AAF family. Of all genes scored, sepA yielded the strongest association with diarrhea (P = 0.002) followed by the increased serum survival gene, iss (p = 0.026), and the outer membrane protease gene ompT (p = 0.046). Notably, the EAEC genomes harbored several genes characteristically associated with other E. coli pathotypes. Our data suggest that a molecular definition of EAEC could comprise E. coli strains harboring AggR and a complete AAF(I-V) or CS22 gene cluster. Further, it is possible that strains meeting this definition could be both enteric bacteria and urinary/systemic pathogens. Enteroaggregative E. coli (EAEC) has been implicated as a common cause of diarrhea in multiple settings and associated with linear growth faltering among children in low-income countries. Unlike other E. coli pathotypes EAEC stands alone in employing a phenotypic, rather than genotypic, definition. Therefore, the lack of a formally recognized genetic definition for EAEC serves to complicate its epidemiologic investigation. In an effort to improve the definition of this pathotype, we generated the most definitive characterization of the pan-genome of EAEC by performing whole genome sequencing on a collection of strains isolated from different geographic settings. We identified a genetic signature of EAEC which could comprise of E. coli strains harboring the EAEC transcriptional activator and its adhesin dependent factors. Further, we found that EAEC strains harbor additional putative virulence genes previously reported in extraintestinal pathogenic E. coli (ExPEC) and, therefore, strains meeting the re-definition could be both enteric bacteria and urinary/systemic pathogens.
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Affiliation(s)
- Nadia Boisen
- Statens Serum Institut, Department of Bacteria, Parasites and Fungi, Copenhagen, Denmark
- * E-mail:
| | - Mark T. Østerlund
- Statens Serum Institut, Department of Bacteria, Parasites and Fungi, Copenhagen, Denmark
| | - Katrine G. Joensen
- Statens Serum Institut, Department of Bacteria, Parasites and Fungi, Copenhagen, Denmark
| | - Araceli E. Santiago
- University of Virginia School of Medicine, Department of Pediatrics, Charlottesville, Virginia, United States of America
| | - Inacio Mandomando
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Alejandro Cravioto
- Universidad Nacional Autónoma de México, Faculty of Medicine, Mexico City, Mexico
| | - Marie A. Chattaway
- Public Health England, Gastrointestinal Bacteria Reference Unit (GBRU), Colindale, United Kingdom
| | - Laura A. Gonyar
- University of Virginia School of Medicine, Department of Pediatrics, Charlottesville, Virginia, United States of America
| | | | - O. Colin Stine
- University of Maryland School of Medicine, Department of Epidemiology and Public Health, Baltimore, Maryland, United States of America
| | - David A. Rasko
- University of Maryland School of Medicine, Institute for Genome Sciences, Department of Microbiology and Immunology, Baltimore, Maryland, United States of America
| | - Flemming Scheutz
- Statens Serum Institut, Department of Bacteria, Parasites and Fungi, Copenhagen, Denmark
| | - James P. Nataro
- University of Virginia School of Medicine, Department of Pediatrics, Charlottesville, Virginia, United States of America
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28
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Liu Z, Liu H, Vera AM, Bernardi RC, Tinnefeld P, Nash MA. High force catch bond mechanism of bacterial adhesion in the human gut. Nat Commun 2020; 11:4321. [PMID: 32859904 PMCID: PMC7456326 DOI: 10.1038/s41467-020-18063-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 08/04/2020] [Indexed: 12/28/2022] Open
Abstract
Bacterial colonization of the human intestine requires firm adhesion of bacteria to insoluble substrates under hydrodynamic flow. Here we report the molecular mechanism behind an ultrastable protein complex responsible for resisting shear forces and adhering bacteria to cellulose fibers in the human gut. Using single-molecule force spectroscopy (SMFS), single-molecule FRET (smFRET), and molecular dynamics (MD) simulations, we resolve two binding modes and three unbinding reaction pathways of a mechanically ultrastable R. champanellensis (Rc) Dockerin:Cohesin (Doc:Coh) complex. The complex assembles in two discrete binding modes with significantly different mechanical properties, with one breaking at ~500 pN and the other at ~200 pN at loading rates from 1-100 nN s-1. A neighboring X-module domain allosterically regulates the binding interaction and inhibits one of the low-force pathways at high loading rates, giving rise to a catch bonding mechanism that manifests under force ramp protocols. Multi-state Monte Carlo simulations show strong agreement with experimental results, validating the proposed kinetic scheme. These results explain mechanistically how gut microbes regulate cell adhesion strength at high shear stress through intricate molecular mechanisms including dual-binding modes, mechanical allostery and catch bonds.
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Affiliation(s)
- Zhaowei Liu
- Institute of Physical Chemistry, Department of Chemistry, University of Basel, 4058, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH Zurich, 4058, Basel, Switzerland
| | - Haipei Liu
- Institute of Physical Chemistry, Department of Chemistry, University of Basel, 4058, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH Zurich, 4058, Basel, Switzerland
| | - Andrés M Vera
- Faculty of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Rafael C Bernardi
- NIH Center for Macromolecular Modeling and Bioinformatics, Theoretical and Computational Biophysics Group, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 61801, Urbana, IL, USA
- Department of Physics, Auburn University, 36849, Auburn, AL, USA
| | - Philip Tinnefeld
- Faculty of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Michael A Nash
- Institute of Physical Chemistry, Department of Chemistry, University of Basel, 4058, Basel, Switzerland.
- Department of Biosystems Science and Engineering, ETH Zurich, 4058, Basel, Switzerland.
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29
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Roszczenko-Jasińska P, Vu HN, Subuyuj GA, Crisostomo RV, Cai J, Lien NF, Clippard EJ, Ayala EM, Ngo RT, Yarza F, Wingett JP, Raghuraman C, Hoeber CA, Martinez-Gomez NC, Skovran E. Gene products and processes contributing to lanthanide homeostasis and methanol metabolism in Methylorubrum extorquens AM1. Sci Rep 2020; 10:12663. [PMID: 32728125 PMCID: PMC7391723 DOI: 10.1038/s41598-020-69401-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 07/09/2020] [Indexed: 11/08/2022] Open
Abstract
Lanthanide elements have been recently recognized as "new life metals" yet much remains unknown regarding lanthanide acquisition and homeostasis. In Methylorubrum extorquens AM1, the periplasmic lanthanide-dependent methanol dehydrogenase XoxF1 produces formaldehyde, which is lethal if allowed to accumulate. This property enabled a transposon mutagenesis study and growth studies to confirm novel gene products required for XoxF1 function. The identified genes encode an MxaD homolog, an ABC-type transporter, an aminopeptidase, a putative homospermidine synthase, and two genes of unknown function annotated as orf6 and orf7. Lanthanide transport and trafficking genes were also identified. Growth and lanthanide uptake were measured using strains lacking individual lanthanide transport cluster genes, and transmission electron microscopy was used to visualize lanthanide localization. We corroborated previous reports that a TonB-ABC transport system is required for lanthanide incorporation to the cytoplasm. However, cells were able to acclimate over time and bypass the requirement for the TonB outer membrane transporter to allow expression of xoxF1 and growth. Transcriptional reporter fusions show that excess lanthanides repress the gene encoding the TonB-receptor. Using growth studies along with energy dispersive X-ray spectroscopy and transmission electron microscopy, we demonstrate that lanthanides are stored as cytoplasmic inclusions that resemble polyphosphate granules.
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Affiliation(s)
- Paula Roszczenko-Jasińska
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, USA
- Institute of Microbiology, University of Warsaw, Warsaw, Poland
| | - Huong N Vu
- Department of Biological Sciences, San José State University, San José, CA, USA
- Department of Microbiology, University of Georgia, Athens, GA, USA
| | - Gabriel A Subuyuj
- Department of Biological Sciences, San José State University, San José, CA, USA
- Department of Microbiology and Molecular Genetics, University of California At Davis, Davis, CA, USA
| | - Ralph Valentine Crisostomo
- Department of Biological Sciences, San José State University, San José, CA, USA
- Molecular Biology Institute, University of California At Los Angeles, Los Angeles, CA, USA
| | - James Cai
- Department of Biological Sciences, San José State University, San José, CA, USA
| | - Nicholas F Lien
- Department of Biological Sciences, San José State University, San José, CA, USA
| | - Erik J Clippard
- Department of Biological Sciences, San José State University, San José, CA, USA
| | - Elena M Ayala
- Department of Biological Sciences, San José State University, San José, CA, USA
| | - Richard T Ngo
- Department of Biological Sciences, San José State University, San José, CA, USA
| | - Fauna Yarza
- Department of Biological Sciences, San José State University, San José, CA, USA
- Department of Biochemistry and Biophysics, University of California At San Francisco, San Francisco, CA, USA
| | - Justin P Wingett
- Department of Biological Sciences, San José State University, San José, CA, USA
| | | | - Caitlin A Hoeber
- Department of Biological Sciences, San José State University, San José, CA, USA
| | - Norma C Martinez-Gomez
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, USA.
- Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, California, USA.
| | - Elizabeth Skovran
- Department of Biological Sciences, San José State University, San José, CA, USA.
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30
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Cho SH, Lee KM, Kim CH, Kim SS. Construction of a Lectin-Glycan Interaction Network from Enterohemorrhagic Escherichia coli Strains by Multi-omics Analysis. Int J Mol Sci 2020; 21:ijms21082681. [PMID: 32290560 PMCID: PMC7215717 DOI: 10.3390/ijms21082681] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/04/2020] [Accepted: 04/07/2020] [Indexed: 11/17/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) causes hemorrhagic colitis and hemolytic uremic syndrome. EHEC infection begins with bacterial adherence to the host intestine via lectin-like adhesins that bind to the intestinal wall. However, EHEC-related lectin–glycan interactions (LGIs) remain unknown. Here, we conducted a genome-wide investigation of putative adhesins to construct an LGI network. We performed microarray-based transcriptomic and proteomic analyses with E. coli EDL933. Using PSORTb-based analysis, potential outer-membrane-embedded adhesins were predicted from the annotated genes of 318 strains. Predicted proteins were classified using TMHMM v2.0, SignalP v5.0, and LipoP v1.0. Functional and protein–protein interaction analyses were performed using InterProScan and String databases, respectively. Structural information of lectin candidate proteins was predicted using Iterative Threading ASSEmbly Refinement (I-TASSER) and Spatial Epitope Prediction of Protein Antigens (SEPPA) tools based on 3D structure and B-cell epitopes. Pathway analysis returned 42,227 Gene Ontology terms; we then selected 2585 lectin candidate proteins by multi-omics analysis and performed homology modeling and B-cell epitope analysis. We predicted a total of 24,400 outer-membrane-embedded proteins from the genome of 318 strains and integrated multi-omics information into the genomic information of the proteins. Our integrated multi-omics data will provide a useful resource for the construction of LGI networks of E. coli.
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Affiliation(s)
- Seung-Hak Cho
- Division of Bacterial Disease Research, Center for Infectious Disease Research, Korea National Institute of Health, Cheongju, Chungchungbuk-do 28160, Korea; (S.-H.C.); (K.M.L.)
| | - Kang Mo Lee
- Division of Bacterial Disease Research, Center for Infectious Disease Research, Korea National Institute of Health, Cheongju, Chungchungbuk-do 28160, Korea; (S.-H.C.); (K.M.L.)
| | - Cheorl-Ho Kim
- Glycobiology Unit, Department of Biological Science, Sungkyunkwan University and Samsung Advanced Institute for Health Science and Technology (SAIHST), Suwon, Gyeonggi-do 16419, Korea
- Correspondence: (C.-H.K.); (S.S.K.); Tel.: +82-031-290-7002 (C.-H.K.); +82-043-719-8400 (S.S.K.); Fax: +82-043-719-8402 (S.S.K.)
| | - Sung Soon Kim
- Division of Bacterial Disease Research, Center for Infectious Disease Research, Korea National Institute of Health, Cheongju, Chungchungbuk-do 28160, Korea; (S.-H.C.); (K.M.L.)
- Correspondence: (C.-H.K.); (S.S.K.); Tel.: +82-031-290-7002 (C.-H.K.); +82-043-719-8400 (S.S.K.); Fax: +82-043-719-8402 (S.S.K.)
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31
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Pimenta AI, Mil‐Homens D, Fialho AM. Burkholderia cenocepacia-host cell contact controls the transcription activity of the trimeric autotransporter adhesin BCAM2418 gene. Microbiologyopen 2020; 9:e998. [PMID: 32097539 PMCID: PMC7142374 DOI: 10.1002/mbo3.998] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/02/2020] [Accepted: 01/04/2020] [Indexed: 12/11/2022] Open
Abstract
Cell-to-cell early contact between pathogens and their host cells is required for the establishment of many infections. Among various surface factors produced by bacteria that allow an organism to become established in a host, the class of adhesins is a primary determinant. Burkholderia cenocepacia adheres to the respiratory epithelium of cystic fibrosis patients and causes chronic inflammation and disease. Cell-to-cell contacts are promoted by various kinds of adhesins, including trimeric autotransporter adhesins (TAAs). We observed that among the 7 TAA genes found in the B. cenocepacia K56-2 genome, two of them (BCAM2418 and BCAS0236) express higher levels of mRNA following physical contact with host cells. Further analysis revealed that the B. cenocepacia K56-2 BCAM2418 gene shows an on-off switch after an initial colonization period, exhibits a strong expression dependent on the host cell type, and enhances its function on cell adhesion. Furthermore, our analysis revealed that adhesion to mucin-coated surfaces dramatically increases the expression levels of BCAM2418. Abrogation of mucin O-glycans turns BCAM2418 gene expression off and impairs bacterial adherence. Overall, our findings suggest that glycosylated extracellular components of host membrane might be a binding site for B. cenocepacia and a signal for the differential expression of the TAA gene BCAM2418.
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Affiliation(s)
- Andreia I. Pimenta
- iBB‐Institute for Bioengineering and BiosciencesInstituto Superior Técnico, University of LisbonLisbonPortugal
| | - Dalila Mil‐Homens
- iBB‐Institute for Bioengineering and BiosciencesInstituto Superior Técnico, University of LisbonLisbonPortugal
| | - Arsenio M. Fialho
- iBB‐Institute for Bioengineering and BiosciencesInstituto Superior Técnico, University of LisbonLisbonPortugal
- Department of BioengineeringInstituto Superior TécnicoUniversity of LisbonLisbonPortugal
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32
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Abstract
Cellular motility is a key function guiding microbial adhesion to interfaces, which is the first step in the formation of biofilms. The close association of biofilms and bioremediation has prompted extensive research aimed at comprehending the physics of microbial locomotion near interfaces. We study the dynamics and statistics of microorganisms in a 'floating biofilm', i.e., a confinement with an air-liquid interface on one side and a liquid-liquid interface on the other. We use a very general mathematical model, based on a multipole representation and probabilistic simulations, to ascertain the spatial distribution of microorganisms in films of different viscosities. Our results reveal that microorganisms can be distributed symmetrically or asymmetrically across the height of the film, depending on their morphology and the ratio of the film's viscosity to that of the fluid substrate. Long-flagellated, elongated bacteria exhibit stable swimming parallel to the liquid-liquid interface when the bacterial film is less viscous than the underlying fluid. Bacteria with shorter flagella on the other hand, swim away from the liquid-liquid interface and accumulate at the free surface. We also analyze microorganism dynamics in a flowing film and show how a microorganism's ability to resist 'flow-induced-erosion' from interfaces is affected by its elongation and mode of propulsion. Our study generalizes past efforts on understanding microorganism dynamics under confinement by interfaces and provides key insights on biofilm initiation at liquid-liquid interfaces.
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Affiliation(s)
- Nikhil Desai
- School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA.
| | - Arezoo M Ardekani
- School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA.
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33
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Ormsby MJ, Johnson SA, Carpena N, Meikle LM, Goldstone RJ, McIntosh A, Wessel HM, Hulme HE, McConnachie CC, Connolly JPR, Roe AJ, Hasson C, Boyd J, Fitzgerald E, Gerasimidis K, Morrison D, Hold GL, Hansen R, Walker D, Smith DGE, Wall DM. Propionic Acid Promotes the Virulent Phenotype of Crohn's Disease-Associated Adherent-Invasive Escherichia coli. Cell Rep 2020; 30:2297-2305.e5. [PMID: 32075765 PMCID: PMC7034058 DOI: 10.1016/j.celrep.2020.01.078] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 08/09/2019] [Accepted: 01/22/2020] [Indexed: 02/07/2023] Open
Abstract
Propionic acid (PA) is a bacterium-derived intestinal antimicrobial and immune modulator used widely in food production and agriculture. Passage of Crohn's disease-associated adherent-invasive Escherichia coli (AIEC) through a murine model, in which intestinal PA levels are increased to mimic the human intestine, leads to the recovery of AIEC with significantly increased virulence. Similar phenotypic changes are observed outside the murine model when AIEC is grown in culture with PA as the sole carbon source; such PA exposure also results in AIEC that persists at 20-fold higher levels in vivo. RNA sequencing identifies an upregulation of genes involved in biofilm formation, stress response, metabolism, membrane integrity, and alternative carbon source utilization. PA exposure also increases virulence in a number of E. coli isolates from Crohn's disease patients. Removal of PA is sufficient to reverse these phenotypic changes. Our data indicate that exposure to PA results in AIEC resistance and increased virulence in its presence.
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Affiliation(s)
- Michael J Ormsby
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Síle A Johnson
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Nuria Carpena
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Lynsey M Meikle
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Robert J Goldstone
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK
| | - Anne McIntosh
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Hannah M Wessel
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Heather E Hulme
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Ceilidh C McConnachie
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - James P R Connolly
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK; Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle-upon-Tyne NE2 4HH, UK
| | - Andrew J Roe
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Conor Hasson
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Joseph Boyd
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Eamonn Fitzgerald
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - Konstantinos Gerasimidis
- Human Nutrition, School of Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow Royal Infirmary, Glasgow G31 2ER, UK
| | - Douglas Morrison
- Scottish Universities Environmental Research Centre, University of Glasgow, Glasgow G75 0QF, UK
| | - Georgina L Hold
- Microbiome Research Centre, St George and Sutherland Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Richard Hansen
- Department of Paediatric Gastroenterology, Hepatology and Nutrition, Royal Hospital for Children, 1345 Govan Road, Glasgow G51 4TF, UK
| | - Daniel Walker
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
| | - David G E Smith
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK
| | - Daniel M Wall
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK.
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Mursalin MH, Coburn PS, Livingston E, Miller FC, Astley R, Flores-Mireles AL, Callegan MC. Bacillus S-Layer-Mediated Innate Interactions During Endophthalmitis. Front Immunol 2020; 11:215. [PMID: 32117322 PMCID: PMC7028758 DOI: 10.3389/fimmu.2020.00215] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/27/2020] [Indexed: 12/14/2022] Open
Abstract
Bacillus endophthalmitis is a severe intraocular infection. Hallmarks of Bacillus endophthalmitis include robust inflammation and rapid loss of vision. We reported that the absence of Bacillus surface layer protein (SLP) significantly blunted endophthalmitis severity. Here, we further investigated SLP in the context of Bacillus-retinal cell interactions and innate immune pathways to explore the mechanisms by which SLP contributes to intraocular inflammation. We compared phenotypes of Wild-type (WT) and SLP deficient (ΔslpA) Bacillus thuringiensis by analyzing bacterial adherence to and phagocytosis by human retinal Muller cells and phagocytosis by mouse neutrophils. Innate immune receptor activation by the Bacillus envelope and purified SLP was analyzed using TLR2/4 reporter cell lines. A synthetic TLR2/4 inhibitor was used as a control for this receptor activation. To induce endophthalmitis, mouse eyes were injected intravitreally with 100 CFU WT or ΔslpA B. thuringiensis. A group of WT infected mice was treated intravitreally with a TLR2/4 inhibitor at 4 h postinfection. At 10 h postinfection, infected eyes were analyzed for viable bacteria, inflammation, and retinal function. We observed that B. thuringiensis SLPs contributed to retinal Muller cell adherence, and protected this pathogen from Muller cell- and neutrophil-mediated phagocytosis. We found that B. thuringiensis envelope activated TLR2 and, surprisingly, TLR4, suggesting the presence of a surface-associated TLR4 agonist in Bacillus. Further investigation showed that purified SLP from B. thuringiensis activated TLR4, as well as TLR2 in vitro. Growth of WT B. thuringiensis was significantly higher and caused greater inflammation in untreated eyes than in eyes treated with the TLR2/4 inhibitor. Retinal function analysis also showed greater retention of A-wave and B-wave function in infected eyes treated with the TLR2/4 inhibitor. The TLR2/4 inhibitor was not antibacterial in vitro, and did not cause inflammation when injected into uninfected eyes. Taken together, these results suggest a potential role for Bacillus SLP in host-bacterial interactions, as well as in endophthalmitis pathogenesis via TLR2- and TLR4-mediated pathways.
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Affiliation(s)
- Md Huzzatul Mursalin
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Phillip S. Coburn
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Dean McGee Eye Institute, Oklahoma City, OK, United States
| | - Erin Livingston
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Frederick C. Miller
- Department of Cell Biology and Department of Family and Preventive Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Roger Astley
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Dean McGee Eye Institute, Oklahoma City, OK, United States
| | - Ana L. Flores-Mireles
- Department of Biological Sciences, University of Notre Dame, South Bend, IN, United States
| | - Michelle C. Callegan
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Dean McGee Eye Institute, Oklahoma City, OK, United States
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35
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Tao L, Kang Y, Zhang L, Shi Q, Li Y, Wu T, Qian A, Sun W, Shan X. Cadaverine reverse transporter (CadB protein) contributes to the virulence of Aeromonas veronii TH0426. Int Microbiol 2020; 23:489-499. [PMID: 31950405 DOI: 10.1007/s10123-020-00120-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 01/06/2020] [Accepted: 01/09/2020] [Indexed: 11/25/2022]
Abstract
Aeromonas veronii is one of the main pathogens causing sepsis and ulcer syndrome in freshwater fish. Analysis of the results of epidemiological investigations in recent years has revealed that the virulence of A. veronii and its tolerance to drugs have been increasing year by year. Currently, most of the research on A. veronii focuses on its isolation, identification, and drug susceptibility, whereas research on its virulence factors and pathogenesis mechanisms is relatively rare. In this study, we identified and obtained the highly expressed TH0426 cadaverine reverse transporter (CadB) of A. veronii. We used efficient suicide plasmid-mediated homologous recombination to delete the cadB gene in TH0426 and constructed a cadB deletion strain. The LD50 of ΔcadB was 93.2 times higher than that of TH0426 in zebrafish, the toxicity of ΔcadB was 9.5 times less than that of TH0426 in EPC cells, and the biofilm formation ability of ΔcadB was 5.6-fold greater than that of TH0426. In addition, motility detection results indicated that ΔcadB had lost its swimming ability. The results of flagellar staining and TEM demonstrated that ΔcadB shed the flagella. In summary, the virulence and adhesion of A. veronii TH0426 were significantly decreased by the deletion of cadB, which might provide a theoretical basis for research into A. veronii virulence factors.
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Affiliation(s)
- LuoTao Tao
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - YuanHuan Kang
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Lei Zhang
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Qiumei Shi
- Key Laboratory of Hebei Province Preventive Veterinary Medicine, Hebei Normal University of Science & Technology, Qinhuangdao, 066004, China
| | - Ying Li
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Tonglei Wu
- Key Laboratory of Hebei Province Preventive Veterinary Medicine, Hebei Normal University of Science & Technology, Qinhuangdao, 066004, China
| | - Aidong Qian
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - WuWen Sun
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, Jilin, China.
| | - Xiaofeng Shan
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, Jilin, China.
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Li T, Shan M, Liu L, Zhao Y, Qi J, Tian M, Wang S, Wu Z, Yu S. Characterization of the Riemerella anatipestifer M949_RS00050 gene. Vet Microbiol 2019; 240:108548. [PMID: 31902494 DOI: 10.1016/j.vetmic.2019.108548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 12/04/2019] [Accepted: 12/04/2019] [Indexed: 11/30/2022]
Abstract
Based on its causing ever-increasing heavy economic losses, Riemerella anatipestifer has been viewed as an important bacterial pathogen in the duck industry worldwide. However, the molecular mechanisms regarding its pathogenicity are poorly understood. In our previous study, we have built a random mutagenesis library of Riemerella anatipestifer CH3 using transposon Tn4351. In this study, we screened the library by determining bacterial median lethal dose in ducklings. A mutant strain showed about 376-fold attenuated virulence in comparison with the wild-type strain CH3 was obtained. Subsequently, the Tn4351 inserted gene was identified as M949_RS00050, which encodes a putative protein containing an outer membrane protein beta-barrel domain by genome walking and sequence analyses. Southern blot analysis indicated a single Tn4351 insertion in the CH3 chromosomal DNA. Inactivation of M949_RS00050 gene did not affect bacterial metabolic activity and the silver stained lipopolysaccharide pattern. However, the bacterial sensitivity to normal duck sera killing and bacterial hydrophobicity were dramatically enhanced in the M949_RS00050 gene inactivated mutant strain, compared to its wild-type strain CH3. Moreover, bacterial adherence and invasion abilities, bacterial capsular polysaccharide quantity, biofilm formation capacity and the bacterial virulence of the mutant strain were obviously decreased, compared to the wild-type strain CH3. Thus, our finding demonstrates that the M949_RS00050 gene functions on multiple bacterial biological properties and virulence in Riemerella anatipestifer.
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Affiliation(s)
- Tao Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China
| | - Min Shan
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China
| | - Lingli Liu
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China
| | - Yanan Zhao
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China
| | - Jingjing Qi
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China
| | - Mingxing Tian
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China
| | - Shaohui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China
| | - Zhi Wu
- Jiangsu Agri-Animal Husbandry Vocational College, Veterinary Bio-Pharmaceutical, Jiangsu Key Laboratory for High-Tech Research and Development of Veterinary Biopharmaceuticals, Taizhou, Jiangsu, China.
| | - Shengqing Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Minhang District, Shanghai, China; Jiangsu Agri-Animal Husbandry Vocational College, Veterinary Bio-Pharmaceutical, Jiangsu Key Laboratory for High-Tech Research and Development of Veterinary Biopharmaceuticals, Taizhou, Jiangsu, China.
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37
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Rehman T, Yin L, Latif MB, Chen J, Wang K, Geng Y, Huang X, Abaidullah M, Guo H, Ouyang P. Adhesive mechanism of different Salmonella fimbrial adhesins. Microb Pathog 2019; 137:103748. [PMID: 31521802 DOI: 10.1016/j.micpath.2019.103748] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 09/10/2019] [Accepted: 09/11/2019] [Indexed: 02/01/2023]
Abstract
Salmonellosis is a serious threat to human and animal health. Salmonella adhesion to the host cell is an initial and most crucial step in the pathogenesis of salmonellosis. Many factors are involved in the adhesion process of Salmonella infection. Fimbriae are one of the most important factors in the adhesion of Salmonella. The Salmonella fimbriae are assembled in three types of assembly pathways: chaperon-usher, nucleation-precipitation, and type IV fimbriae. These assembly pathways lead to multiple types of fimbriae. Salmonella fimbriae bind to host cell receptors to initiate adhesion. So far, many receptors have been identified, such as Toll-like receptors. However, several receptors that may be involved in the adhesive mechanism of Salmonella fimbriae are still un-identified. This review aimed to summarize the types of Salmonella fimbriae produced by different assembly pathways and their role in adhesion. It also enlisted previously discovered receptors involved in adhesion. This review might help readers to develop a comprehensive understanding of Salmonella fimbriae, their role in adhesion, and recently developed strategies to counter Salmonella infection.
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Affiliation(s)
- Tayyab Rehman
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Lizi Yin
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Muhammad Bilal Latif
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, 44195, Ohio, USA.
| | - Jiehao Chen
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Kaiyu Wang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Yi Geng
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Xiaoli Huang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Muhammad Abaidullah
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Hongrui Guo
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Ping Ouyang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
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Feng Y, Liu L, Lin J, Ma K, Long H, Wei L, Xie Y, McNally A, Zong Z. Key evolutionary events in the emergence of a globally disseminated, carbapenem resistant clone in the Escherichia coli ST410 lineage. Commun Biol 2019; 2:322. [PMID: 31482141 PMCID: PMC6715731 DOI: 10.1038/s42003-019-0569-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 08/05/2019] [Indexed: 02/05/2023] Open
Abstract
There is an urgent need to understand the global epidemiological landscape of carbapenem-resistant Escherichia coli (CREC). Here we provide combined genomic and phenotypic characterization of the emergence of a CREC clone from the ST410 lineage. We show that the clone expands with a single plasmid, within which there is frequent switching of the carbapenemase gene type between blaNDM and blaOXA-181 with no impact on plasmid stability or fitness. A search for clone-specific traits identified unique alleles of genes involved in adhesion and iron acquisition, which have been imported via recombination. These recombination-derived allelic switches had no impact on virulence in a simple infection model, but decreased efficiency in binding to abiotic surfaces and greatly enhanced fitness in iron limited conditions. Together our data show a footprint for evolution of a CREC clone, whereby recombination drives new alleles into the clone which provide a competitive advantage in colonizing mammalian hosts.
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Affiliation(s)
- Yu Feng
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- Division of Infectious Diseases, State Key Laboratory of Biotherapy, Chengdu, China
- Center for Pathogen Research, West China Hospital, Sichuan University, Chengdu, China
| | - Lu Liu
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- Division of Infectious Diseases, State Key Laboratory of Biotherapy, Chengdu, China
- Center for Pathogen Research, West China Hospital, Sichuan University, Chengdu, China
| | - Ji Lin
- Department of Infection Control, West China Hospital, Sichuan University, Chengdu, China
| | - Ke Ma
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- Division of Infectious Diseases, State Key Laboratory of Biotherapy, Chengdu, China
- Center for Pathogen Research, West China Hospital, Sichuan University, Chengdu, China
| | - Haiyan Long
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- Division of Infectious Diseases, State Key Laboratory of Biotherapy, Chengdu, China
- Center for Pathogen Research, West China Hospital, Sichuan University, Chengdu, China
| | - Li Wei
- Department of Infection Control, West China Hospital, Sichuan University, Chengdu, China
| | - Yi Xie
- Laboratory of Clinical Microbiology, Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Alan McNally
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Zhiyong Zong
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- Division of Infectious Diseases, State Key Laboratory of Biotherapy, Chengdu, China
- Center for Pathogen Research, West China Hospital, Sichuan University, Chengdu, China
- Department of Infection Control, West China Hospital, Sichuan University, Chengdu, China
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Karmakar K, Nair AV, Chandrasekharan G, Garai P, Nath U, Nataraj KN, N B P, Chakravortty D. Rhizospheric life of Salmonella requires flagella-driven motility and EPS-mediated attachment to organic matter and enables cross-kingdom invasion. FEMS Microbiol Ecol 2019; 95:fiz107. [PMID: 31271416 DOI: 10.1093/femsec/fiz107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 07/03/2019] [Indexed: 09/19/2023] Open
Abstract
Salmonella is an established pathogen of the members of the kingdom Animalia. Reports indicate that the association of Salmonella with fresh, edible plant products occurs at the pre-harvest state, i.e. in the field. In this study, we follow the interaction of Salmonella Typhimurium with the model plant Arabidopsis thaliana to understand the process of migration in soil. Plant factors like root exudates serve as chemo-attractants. Our ex situ experiments allowed us to track Salmonella from its free-living state to the endophytic state. We found that genes encoding two-component systems and proteins producing extracellular polymeric substances are essential for Salmonella to adhere to the soil and roots. To understand the trans-kingdom flow of Salmonella, we fed the contaminated plants to mice and observed that it invades and colonizes liver and spleen. To complete the disease cycle, we re-established the infection in plant by mixing the potting mixture with the fecal matter collected from the diseased animals. Our experiments revealed a cross-kingdom invasion by the pathogen via passage through a murine intermediate, a mechanism for its persistence in the soil and invasion in a non-canonical host. These results form a basis to break the life-cycle of Salmonella before it reaches its animal host and thus reduce Salmonella contamination of food products.
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Affiliation(s)
- Kapudeep Karmakar
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Abhilash Vijay Nair
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Giridhar Chandrasekharan
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
- Department of Microbiology, St. Joseph's College Autonomous, Bangalore, India
| | - Preeti Garai
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Utpal Nath
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Karaba N Nataraj
- Department of Crop Physiology, University of Agricultural Science, Bangalore, India
| | - Prakash N B
- Department of Soil Science and Agricultural Chemistry, University of Agricultural Science, Bangalore, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
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40
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Armbruster CR, Lee CK, Parker-Gilham J, de Anda J, Xia A, Zhao K, Murakami K, Tseng BS, Hoffman LR, Jin F, Harwood CS, Wong GCL, Parsek MR. Heterogeneity in surface sensing suggests a division of labor in Pseudomonas aeruginosa populations. eLife 2019; 8:e45084. [PMID: 31180327 PMCID: PMC6615863 DOI: 10.7554/elife.45084] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 06/08/2019] [Indexed: 12/27/2022] Open
Abstract
The second messenger signaling molecule cyclic diguanylate monophosphate (c-di-GMP) drives the transition between planktonic and biofilm growth in many bacterial species. Pseudomonas aeruginosa has two surface sensing systems that produce c-di-GMP in response to surface adherence. Current thinking in the field is that once cells attach to a surface, they uniformly respond by producing c-di-GMP. Here, we describe how the Wsp system generates heterogeneity in surface sensing, resulting in two physiologically distinct subpopulations of cells. One subpopulation has elevated c-di-GMP and produces biofilm matrix, serving as the founders of initial microcolonies. The other subpopulation has low c-di-GMP and engages in surface motility, allowing for exploration of the surface. We also show that this heterogeneity strongly correlates to surface behavior for descendent cells. Together, our results suggest that after surface attachment, P. aeruginosa engages in a division of labor that persists across generations, accelerating early biofilm formation and surface exploration.
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Affiliation(s)
| | - Calvin K Lee
- Department of BioengineeringUniversity of California, Los AngelesLos AngelesUnited States
- Department of Chemistry and BiochemistryUniversity of California, Los AngelesLos AngelesUnited States
- California NanoSystems InstituteUniversity of California, Los AngelesLos AngelesUnited States
| | | | - Jaime de Anda
- Department of BioengineeringUniversity of California, Los AngelesLos AngelesUnited States
- Department of Chemistry and BiochemistryUniversity of California, Los AngelesLos AngelesUnited States
- California NanoSystems InstituteUniversity of California, Los AngelesLos AngelesUnited States
| | - Aiguo Xia
- Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefeiChina
| | - Kun Zhao
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and TechnologyTianjin UniversityTianjinChina
- Collaborative Innovation Centre of Chemical Science and EngineeringTianjin UniversityTianjinChina
| | - Keiji Murakami
- Department of Oral Microbiology, Institute of Biomedical SciencesTokushima University Graduate SchoolTokushimaJapan
| | - Boo Shan Tseng
- School of Life SciencesUniversity of NevadaLas VegasUnited States
| | - Lucas R Hoffman
- Department of MicrobiologyUniversity of WashingtonSeattleUnited States
- Department of PediatricsUniversity of WashingtonSeattleUnited States
| | - Fan Jin
- Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefeiChina
- Institute of Synthetic BiologyShenzhen Institutes of Advanced Technology, Chinese Academy of SciencesShenzhenChina
| | | | - Gerard CL Wong
- Department of BioengineeringUniversity of California, Los AngelesLos AngelesUnited States
- Department of Chemistry and BiochemistryUniversity of California, Los AngelesLos AngelesUnited States
- California NanoSystems InstituteUniversity of California, Los AngelesLos AngelesUnited States
| | - Matthew R Parsek
- Department of MicrobiologyUniversity of WashingtonSeattleUnited States
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
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Abstract
For proper biofilm formation, bacteria must have mechanisms in place to sense adhesion to surfaces. In Escherichia coli, the CpxAR and RcsCDB systems have been reported to sense surfaces. The CpxAR system is widely considered to be responsible for sensing attachment, specifically to hydrophobic surfaces. Here, using both single-cell and population-level analyses, we confirm RcsCDB activation upon surface contact, but find that the CpxAR system is not activated, in contrast to what had earlier been reported. Thus, the role of CpxAR in surface sensing and initiation of biofilm formation should be reconsidered.
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Affiliation(s)
- Tom E. P. Kimkes
- Molecular Systems Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Matthias Heinemann
- Molecular Systems Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
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Kłyż A, Piekarowicz A. Phage proteins are expressed on the surface of Neisseria gonorrhoeae and are potential vaccine candidates. PLoS One 2018; 13:e0202437. [PMID: 30138416 PMCID: PMC6107182 DOI: 10.1371/journal.pone.0202437] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 08/02/2018] [Indexed: 11/19/2022] Open
Abstract
All Neisseria gonorrhoeae strains whose DNA sequences have been determined possess filamentous phage sequences representing their full genomes. The presence of filamentous phage DNA sequences in all sequenced N. gonorrhoeae strains suggest that purified phage particles might be used as a gonococcal vaccine. To test this hypothesis, we purified filamentous NgoΦfil phages and immunized rabbits subcutaneously. The elicited sera contained large quantities of anti-phage IgG and IgA antibodies that bound to the surface of N. gonorrhoeae cells, as shown by ELISA and flow cytometry. The elicited sera bound to the structural NgoΦ6fil proteins present in phage particles and to N. gonorrhoeae cells. The sera did not react with gonococcal outer membrane proteins. The sera also had bactericidal activity and blocked adhesion of gonococci to tissue culture cells. These data demonstrate that NgoΦfil phage particles can induce antibodies with anti-gonococcal activity and may be a candidate for vaccine development.
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Affiliation(s)
- Aneta Kłyż
- Department of Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
- * E-mail: (AK); (AP)
| | - Andrzej Piekarowicz
- Department of Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
- * E-mail: (AK); (AP)
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Reddy S, Zishiri OT. Genetic characterisation of virulence genes associated with adherence, invasion and cytotoxicity in Campylobacter spp. isolated from commercial chickens and human clinical cases. Onderstepoort J Vet Res 2018; 85:e1-e9. [PMID: 29781670 PMCID: PMC6238761 DOI: 10.4102/ojvr.v85i1.1507] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/06/2017] [Accepted: 10/20/2017] [Indexed: 12/25/2022] Open
Abstract
Virulence-associated genes have been recognised and detected in Campylobacter species. The majority of them have been proven to be associated with pathogenicity. This study aimed to detect the presence of virulence genes associated with pathogenicity and responsible for invasion, expression of adherence, colonisation and production of the cytolethal distending toxin (cdt) in Campylobacter jejuni and Campylobacter coli. Commercial chicken faecal samples were randomly sampled from chicken farms within the Durban metropolitan area in South Africa. Furthermore, human clinical Campylobacter spp. isolates were randomly sampled from a private pathology laboratory in South Africa. Out of a total of 100 chicken faecal samples, 78% (n = 78) were positive for Campylobacter growth on modified charcoal cefoperazone deoxycholate and from the random laboratory collection of 100 human clinical isolates, 83% (n = 83) demonstrated positive Campylobacter spp. growth following culturing methods. These samples were screened for the presence of the following virulence genes: cadF, hipO, asp, ciaB, dnaJ, pldA, cdtA, cdtB and cdtC. As expected, the cadF gene was present in 100% of poultry (n = 78) and human clinical isolates (n = 83). Campylobacter jejuni was the main species detected in both poultry and human clinical isolates, whilst C. coli were detected at a significantly lower percentage (p < 0.05). Eight per cent of the C. jejuni from human clinical isolates had all virulence genes that were investigated. Only one C. coli isolate demonstrated the presence of all the virulence genes investigated; however, the pldA virulence gene was detected in 100% of the C. coli isolates in poultry and a high percentage (71%) in human clinical C. coli isolates as well. The detection of cdt genes was found at higher frequency in poultry than human clinical isolates. The high prevalence rates of virulence genes detected in poultry and human clinical isolates demonstrate their significance in the pathogenicity of Campylobacter species.
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Brauge T, Faille C, Sadovskaya I, Charbit A, Benezech T, Shen Y, Loessner MJ, Bautista JR, Midelet-Bourdin G. The absence of N-acetylglucosamine in wall teichoic acids of Listeria monocytogenes modifies biofilm architecture and tolerance to rinsing and cleaning procedures. PLoS One 2018; 13:e0190879. [PMID: 29320565 PMCID: PMC5761963 DOI: 10.1371/journal.pone.0190879] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 12/21/2017] [Indexed: 11/18/2022] Open
Abstract
The wall teichoic acid (WTA) is the major carbohydrate found within the extracellular matrix of the Listeria monocytogenes biofilm. We first addressed the frequency of spontaneous mutations in two genes (lmo2549 and lmo2550) responsible for the GlcNAcylation in 93 serotype 1/2a strains that were mainly isolated from seafood industries. We studied the impact of mutations in lmo2549 or lmo2550 genes on biofilm formation by using one mutant carrying a natural mutation inactivating the lmo2550 gene (DSS 1130 BFA2 strain) and two EGD-e mutants that lack respective genes by in-frame deletion of lmo2549 or lmo2550 using splicing-by-overlap-extension PCR, followed by allelic exchange mutagenesis. The lmo2550 gene mutation, occurring in around 50% isolates, caused a decrease in bacterial adhesion to stainless steel compared to wild-type EGD-e strain during the adhesion step. On the other hand, bacterial population weren't significantly different after 24h-biofilm formation. The biofilm architecture was different between the wild-type strain and the two mutants inactivated for lmo2549 or lmo2550 genes respectively with the presence of bacterial micro-colonies for mutants which were not observed in the wild-type EGD-e strain biofilm. These differences might account for the stronger hydrophilic surface exhibited by the mutant cells. Upon a water flow or to a cleaning procedure at a shear stress of 0.16 Pa, the mutant biofilms showed the higher detachment rate compared to wild-type strain. Meanwhile, an increase in the amount of residual viable but non-culturable population on stainless steel was recorded in two mutants. Our data suggests that the GlcNAc residue of WTA played a role in adhesion and biofilm formation of Listeria monocyctogenes.
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Affiliation(s)
- Thomas Brauge
- ANSES, Laboratory for food safety, Boulogne sur Mer, France
| | - Christine Faille
- UMR UMET, INRA, CNRS, Université Lille 1, Villeneuve d’Ascq, France
| | - Irina Sadovskaya
- Université du Littoral-Côte d’Opale, Institut Charles Violette EA 7394, USC Anses, Boulogne sur Mer, France
| | | | - Thierry Benezech
- UMR UMET, INRA, CNRS, Université Lille 1, Villeneuve d’Ascq, France
| | - Yang Shen
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Martin J. Loessner
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
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Carkaci D, Højholt K, Nielsen XC, Dargis R, Rasmussen S, Skovgaard O, Fuursted K, Andersen PS, Stegger M, Christensen JJ. Genomic characterization, phylogenetic analysis, and identification of virulence factors in Aerococcus sanguinicola and Aerococcus urinae strains isolated from infection episodes. Microb Pathog 2017; 112:327-340. [PMID: 28943151 DOI: 10.1016/j.micpath.2017.09.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 09/14/2017] [Accepted: 09/18/2017] [Indexed: 11/18/2022]
Abstract
Aerococcus sanguinicola and Aerococcus urinae are emerging pathogens in clinical settings mostly being causative agents of urinary tract infections (UTIs), urogenic sepsis and more seldomly complicated infective endocarditis (IE). Limited knowledge exists concerning the pathogenicity of these two species. Eight clinical A. sanguinicola (isolated from 2009 to 2015) and 40 clinical A. urinae (isolated from 1984 to 2015) strains from episodes of UTIs, bacteremia, and IE were whole-genome sequenced (WGS) to analyze genomic diversity and characterization of virulence genes involved in the bacterial pathogenicity. A. sanguinicola genome sizes were 2.06-2.12 Mb with 47.4-47.6% GC-contents, and 1783-1905 genes were predicted whereof 1170 were core-genes. In case of A. urinae strains, the genome sizes were 1.93-2.44 Mb with 41.6-42.6% GC-contents, and 1708-2256 genes of which 907 were core-genes. Marked differences were observed within A. urinae strains with respect to the average genome sizes, number and sequence identity of core-genes, proteome conservations, phylogenetic analysis, and putative capsular polysaccharide (CPS) loci sequences. Strains of A. sanguinicola showed high degree of homology. Phylogenetic analyses showed the 40 A. urinae strains formed two clusters according to two time periods: 1984-2004 strains and 2010-2015 strains. Genes that were homologs to virulence genes associated with bacterial adhesion and antiphagocytosis were identified by aligning A. sanguinicola and A. urinae pan- and core-genes against Virulence Factors of Bacterial Pathogens (VFDB). Bacterial adherence associated gene homologs were present in genomes of A. sanguinicola (htpB, fbpA, lmb, and ilpA) and A. urinae (htpB, lap, lmb, fbp54, and ilpA). Fifteen and 11-16 CPS gene homologs were identified in genomes of A. sanguinicola and A. urinae strains, respectively. Analysis of these genes identified one type of putative CPS locus within all A. sanguinicola strains. In A. urinae genomes, five different CPS loci types were identified with variations in CPS locus sizes, genetic content, and structural organization. In conclusion, this is the first study dealing with WGS and comparative genomics of clinical A. sanguinicola and A. urinae strains from episodes of UTIs, bacteremia, and IE. Gene homologs associated with antiphagocytosis and bacterial adherence were identified and genetic variability was observed within A. urinae genomes. These findings contribute with important knowledge and basis for future molecular and experimental pathogenicity study of UTIs, bacteremia, and IE causing A. sanguinicola and A. urinae strains.
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Affiliation(s)
- Derya Carkaci
- Department of Clinical Microbiology, Slagelse Hospital, Slagelse, Denmark; Department of Science and Environment, Roskilde University, Roskilde, Denmark; Department of Microbiology & Infection Control, Statens Serum Institut, Copenhagen, Denmark.
| | - Katrine Højholt
- Department of Clinical Microbiology, Slagelse Hospital, Slagelse, Denmark; Department of Bio and Health Informatics, Technical University of Denmark, Kongens Lyngby, Denmark.
| | | | - Rimtas Dargis
- Department of Clinical Microbiology, Slagelse Hospital, Slagelse, Denmark.
| | - Simon Rasmussen
- Department of Bio and Health Informatics, Technical University of Denmark, Kongens Lyngby, Denmark.
| | - Ole Skovgaard
- Department of Science and Environment, Roskilde University, Roskilde, Denmark.
| | - Kurt Fuursted
- Department of Microbiology & Infection Control, Statens Serum Institut, Copenhagen, Denmark.
| | - Paal Skytt Andersen
- Department of Microbiology & Infection Control, Statens Serum Institut, Copenhagen, Denmark; Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Marc Stegger
- Department of Microbiology & Infection Control, Statens Serum Institut, Copenhagen, Denmark.
| | - Jens Jørgen Christensen
- Department of Clinical Microbiology, Slagelse Hospital, Slagelse, Denmark; Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
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Bedrunka P, Graumann PL. Subcellular clustering of a putative c-di-GMP-dependent exopolysaccharide machinery affecting macro colony architecture in Bacillus subtilis. Environ Microbiol Rep 2017; 9:211-222. [PMID: 27897378 DOI: 10.1111/1758-2229.12496] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 10/25/2016] [Accepted: 11/16/2016] [Indexed: 06/06/2023]
Abstract
The structure of bacterial biofilms is predominantly established through the secretion of extracellular polymeric substances (EPS). They show that Bacillus subtilis contains an operon (ydaJ-N) whose induction leads to increased Congo Red staining of biofilms and strongly altered biofilm architecture, suggesting that it mediates the production of an unknown exopolysaccharide. Supporting this idea, overproduction of YdaJKLMN leads to cell clumping during exponential growth in liquid culture, and also causes colony morphology alterations in wild type cells, as well as in a mutant background lacking the major exopolysaccharide of B. subtilis. The first gene product of the operon, YdaJ, appears to modify the overproduction effects, but is not essential for cell clumping or altered colony morphology, while the presence of the c-di-GMP receptor YdaK is required, suggesting an involvement of second messenger c-di-GMP. YdaM, YdaN and YdaK colocalize to clusters predominantly at the cell poles and are statically positioned at this subcellular site, similar to other exopolysaccharide machinery components in other bacteria. Their analysis reveals that B. subtilis contains a static subcellular assembly of an EPS machinery that affects cell aggregation and biofilm formation.
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Affiliation(s)
- Patricia Bedrunka
- LOEWE SYNMIKRO, LOEWE Center for Synthetic Microbiology and Department of Chemistry, Philipps University Marburg, Hans-Meerwein Strasse, Marburg, 35043, Germany
| | - Peter L Graumann
- LOEWE SYNMIKRO, LOEWE Center for Synthetic Microbiology and Department of Chemistry, Philipps University Marburg, Hans-Meerwein Strasse, Marburg, 35043, Germany
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Ciszewski M, Szewczyk EM. Potential Factors Enabling Human Body Colonization by Animal Streptococcus dysgalactiae subsp. equisimilis Strains. Curr Microbiol 2017; 74:650-654. [PMID: 28314902 PMCID: PMC5376390 DOI: 10.1007/s00284-017-1232-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 03/14/2017] [Indexed: 12/02/2022]
Abstract
Streptococcus dysgalactiae subsp. equisimilis (SDSE) is a pyogenic, Lancefield C or G streptococcal pathogen. Until recently, it has been considered as an exclusive animal pathogen. Nowadays, it is responsible for both animal infections in wild animals, pets, and livestock and human infections often clinically similar to the ones caused by group A streptococcus (Streptococcus pyogenes). The risk of zoonotic infection is the most significant in people having regular contact with animals, such as veterinarians, cattlemen, and farmers. SDSE is also prevalent on skin of healthy dogs, cats, and horses, which pose a risk also to people having contact with companion animals. The main aim of this study was to evaluate if there are features differentiating animal and human SDSE isolates, especially in virulence factors involved in the first stages of pathogenesis (adhesion and colonization). Equal groups of human and animal SDSE clinical strains were obtained from superficial infections (skin, wounds, abscesses). The presence of five virulence genes (prtF1, prtF2, lmb, cbp, emm type) was evaluated, as well as ability to form bacterial biofilm and produce BLIS (bacteriocin-like inhibitory substances) which are active against human skin microbiota. The study showed that the presence of genes coding for fibronectin-binding protein and M protein, as well as BLIS activity inhibiting the growth of Corynebacterium spp. strains might constitute the virulence factors which are necessary to colonize human organism, whereas they are not crucial in animal infections. Those virulence factors might be horizontally transferred from human streptococci to animal SDSE strains, enabling their ability to colonize human organism.
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Affiliation(s)
- Marcin Ciszewski
- Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Łódź, 137 Pomorska St., 90-235, Lodz, Poland.
| | - Eligia M Szewczyk
- Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Łódź, 137 Pomorska St., 90-235, Lodz, Poland
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Li M, Cai RJ, Li CL, Song S, Li Y, Jiang ZY, Yang DX. Deletion of ssnA Attenuates the Pathogenicity of Streptococcus suis and Confers Protection against Serovar 2 Strain Challenge. PLoS One 2017; 12:e0169791. [PMID: 28081204 PMCID: PMC5232344 DOI: 10.1371/journal.pone.0169791] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 12/21/2016] [Indexed: 11/19/2022] Open
Abstract
Streptococcus suis serotype 2 (SS2) is a major porcine and human pathogen which causes arthritis, meningitis, and septicemia. Streptococcus suis nuclease A (SsnA) is a recently discovered deoxyribonuclease (DNase), which has been demonstrated to contribute to escape killing in neutrophil extracellular traps (NETs). To further determine the effects of ssnA on virulence, the ssnA deletion mutant (ΔssnA) and its complemented strain (C-ΔssnA) were constructed. The ability of ΔssnA mutant to interact with human laryngeal epithelial cell (Hep-2) was evaluated and it exhibited dramatically decreased ability to adhere to and invade Hep-2 cells. This mutation was found to exhibit significant attenuation of virulence when evaluated in CD1 mice, suggesting ssnA plays a critical role in the pathogenesis of SS2. Finally, we found that immunization with the ΔssnA mutant triggered both antibody responses and cell-mediated immunity, and conferred 80% protection against virulent SS2 challenge in mice. Taken together, our results suggest that ΔssnA represents an attractive candidate for designing an attenuated live vaccine against SS2.
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Affiliation(s)
- Miao Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
| | - Ru-Jian Cai
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
- * E-mail: (CLL); (RJC)
| | - Chun-Ling Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
- * E-mail: (CLL); (RJC)
| | - Shuai Song
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
| | - Yan Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
| | - Zhi-Yong Jiang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
| | - Dong-Xia Yang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
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Pérez-Cruz C, Cañas MA, Giménez R, Badia J, Mercade E, Baldomà L, Aguilera L. Membrane Vesicles Released by a hypervesiculating Escherichia coli Nissle 1917 tolR Mutant Are Highly Heterogeneous and Show Reduced Capacity for Epithelial Cell Interaction and Entry. PLoS One 2016; 11:e0169186. [PMID: 28036403 PMCID: PMC5201253 DOI: 10.1371/journal.pone.0169186] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 12/13/2016] [Indexed: 12/18/2022] Open
Abstract
Membrane vesicles (MVs) produced by Gram-negative bacteria are being explored for novel clinical applications due to their ability to deliver active molecules to distant host cells, where they can exert immunomodulatory properties. MVs released by the probiotic Escherichia coli Nissle 1917 (EcN) are good candidates for testing such applications. However, a drawback for such studies is the low level of MV isolation from in vitro culture supernatants, which may be overcome by the use of mutants in cell envelope proteins that yield a hypervesiculation phenotype. Here, we confirm that a tolR mutation in EcN increases MV production, as determined by protein, LPS and fluorescent lipid measurements. Transmission electron microscopy (TEM) of negatively stained MVs did not reveal significant differences with wild type EcN MVs. Conversely, TEM observation after high-pressure freezing followed by freeze substitution of bacterial samples, together with cryo-TEM observation of plunge-frozen hydrated isolated MVs showed considerable structural heterogeneity in the EcN tolR samples. In addition to common one-bilayer vesicles (OMVs) and the recently described double-bilayer vesicles (O-IMVs), other types of MVs were observed. Time-course experiments of MV uptake in Caco-2 cells using rhodamine- and DiO-labelled MVs evidenced that EcN tolR MVs displayed reduced internalization levels compared to the wild-type MVs. The low number of intracellular MVs was due to a lower cell binding capacity of the tolR-derived MVs, rather than a different entry pathway or mechanism. These findings indicate that heterogeneity of MVs from tolR mutants may have a major impact on vesicle functionality, and point to the need for conducting a detailed structural analysis when MVs from hypervesiculating mutants are to be used for biotechnological applications.
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Affiliation(s)
- Carla Pérez-Cruz
- Secció de Microbiologia, Departament de Biologia, Sanitat i Medi Ambient, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| | - María-Alexandra Cañas
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina de la Universitat de Barcelona, Barcelona, Spain
| | - Rosa Giménez
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina de la Universitat de Barcelona, Barcelona, Spain
| | - Josefa Badia
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina de la Universitat de Barcelona, Barcelona, Spain
| | - Elena Mercade
- Secció de Microbiologia, Departament de Biologia, Sanitat i Medi Ambient, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| | - Laura Baldomà
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina de la Universitat de Barcelona, Barcelona, Spain
- * E-mail:
| | - Laura Aguilera
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina de la Universitat de Barcelona, Barcelona, Spain
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50
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Diene SM, François P, Zbinden A, Entenza JM, Resch G. Comparative Genomics Analysis of Streptococcus tigurinus Strains Identifies Genetic Elements Specifically and Uniquely Present in Highly Virulent Strains. PLoS One 2016; 11:e0160554. [PMID: 27505001 PMCID: PMC4978470 DOI: 10.1371/journal.pone.0160554] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 07/21/2016] [Indexed: 02/07/2023] Open
Abstract
Streptococcus tigurinus is responsible for severe invasive infections such as infective endocarditis, spondylodiscitis and meningitis. As described, S. tigurinus isolates AZ_3aT and AZ_14 were highly virulent (HV phenotype) in an experimental model of infective endocarditis and showed enhanced adherence and invasion of human endothelial cells when compared to low virulent S. tigurinus isolate AZ_8 (LV phenotype). Here, we sought whether genetic determinants could explain the higher virulence of AZ_3aT and AZ_14 isolates. Several genetic determinants specific to the HV strains were identified through extensive comparative genomics amongst which some were thought to be highly relevant for the observed HV phenotype. These included i) an iron uptake and metabolism operon, ii) an ascorbate assimilation operon, iii) a newly acquired PI-2-like pilus islets described for the first time in S. tigurinus, iv) a hyaluronate metabolism operon, v) an Entner-Doudoroff pathway of carbohydrates metabolism, and vi) an alternate pathways for indole biosynthesis. We believe that the identified genomic features could largely explain the phenotype of high infectivity of the two HV S. tigurinus strains. Indeed, these features include determinants that could be involved at different stages of the disease such as survival of S. tigurinus in blood (iron uptake and ascorbate metabolism operons), initial attachment of bacterial pathogen to the damaged cardiac tissue and/or vegetation that formed on site (PI-2-like pilus islets), tissue invasion (hyaluronate operon and Entner-Doudoroff pathway) and regulation of pathogenicity (indole biosynthesis pathway).
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Affiliation(s)
- Seydina M. Diene
- Genomic Research Laboratory, Geneva University Hospitals, Geneva, Switzerland
| | - Patrice François
- Genomic Research Laboratory, Geneva University Hospitals, Geneva, Switzerland
| | - Andrea Zbinden
- Institute of Medical Virology, University of Zurich, Zurich, Switzerland
| | - José Manuel Entenza
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Grégory Resch
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
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