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Melgar-Rodríguez S, Polanco A, Ríos-Muñoz J, García M, Sierra-Cristancho A, González-Osuna L, Díaz-Zúñiga J, Carvajal P, Vernal R, Bravo D. Differential Response of Human Dendritic Cells upon Stimulation with Encapsulated or Non-Encapsulated Isogenic Strains of Porphyromonas gingivalis. Int J Mol Sci 2024; 25:4510. [PMID: 38674095 PMCID: PMC11049913 DOI: 10.3390/ijms25084510] [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: 01/31/2024] [Revised: 04/12/2024] [Accepted: 04/17/2024] [Indexed: 04/28/2024] Open
Abstract
During periodontitis, the extracellular capsule of Porphyromonas gingivalis favors alveolar bone loss by inducing Th1 and Th17 patterns of lymphocyte response in the infected periodontium. Dendritic cells recognize bacterial antigens and present them to T lymphocytes, defining their activation and polarization. Thus, dendritic cells could be involved in the Th1 and Th17 response induced against the P. gingivalis capsule. Herein, monocyte-derived dendritic cells were obtained from healthy individuals and then stimulated with different encapsulated strains of P. gingivalis or two non-encapsulated isogenic mutants. Dendritic cell differentiation and maturation were analyzed by flow cytometry. The mRNA expression levels for distinct Th1-, Th17-, or T-regulatory-related cytokines and transcription factors, as well as TLR2 and TLR4, were assessed by qPCR. In addition, the production of IL-1β, IL-6, IL-23, and TNF-α was analyzed by ELISA. The encapsulated strains and non-encapsulated mutants of P. gingivalis induced dendritic cell maturation to a similar extent; however, the pattern of dendritic cell response was different. In particular, the encapsulated strains of P. gingivalis induced higher expression of IRF4 and NOTCH2 and production of IL-1β, IL-6, IL-23, and TNF-α compared with the non-encapsulated mutants, and thus, they showed an increased capacity to trigger Th1 and Th17-type responses in human dendritic cells.
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Affiliation(s)
- Samanta Melgar-Rodríguez
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile
| | - Alan Polanco
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
| | - Jearitza Ríos-Muñoz
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
- Biomedical Research Center, Faculty of Medicine, Universidad de Valparaíso, Valparaíso 2360102, Chile
| | - Michelle García
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
| | - Alfredo Sierra-Cristancho
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
- Faculty of Dentistry, Universidad Andrés Bello, Santiago 8370035, Chile
| | - Luis González-Osuna
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
| | - Jaime Díaz-Zúñiga
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile
| | - Paola Carvajal
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile
| | - Rolando Vernal
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile; (S.M.-R.); (A.P.); (J.R.-M.); (M.G.); (A.S.-C.); (L.G.-O.); (J.D.-Z.); (P.C.)
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago 8380492, Chile
| | - Denisse Bravo
- Laboratorio de Interacciones Microbianas, Faculty of Dentistry, Universidad Andrés Bello, Santiago 8370035, Chile
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2
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Kuklewicz J, Zimmer J. Molecular insights into capsular polysaccharide secretion. Nature 2024; 628:901-909. [PMID: 38570679 PMCID: PMC11041684 DOI: 10.1038/s41586-024-07248-9] [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: 08/11/2023] [Accepted: 02/27/2024] [Indexed: 04/05/2024]
Abstract
Capsular polysaccharides (CPSs) fortify the cell boundaries of many commensal and pathogenic bacteria1. Through the ABC-transporter-dependent biosynthesis pathway, CPSs are synthesized intracellularly on a lipid anchor and secreted across the cell envelope by the KpsMT ABC transporter associated with the KpsE and KpsD subunits1,2. Here we use structural and functional studies to uncover crucial steps of CPS secretion in Gram-negative bacteria. We show that KpsMT has broad substrate specificity and is sufficient for the translocation of CPSs across the inner bacterial membrane, and we determine the cell surface organization and localization of CPSs using super-resolution fluorescence microscopy. Cryo-electron microscopy analyses of the KpsMT-KpsE complex in six different states reveal a KpsE-encaged ABC transporter, rigid-body conformational rearrangements of KpsMT during ATP hydrolysis and recognition of a glycolipid inside a membrane-exposed electropositive canyon. In vivo CPS secretion assays underscore the functional importance of canyon-lining basic residues. Combined, our analyses suggest a molecular model of CPS secretion by ABC transporters.
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Affiliation(s)
- Jeremi Kuklewicz
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Jochen Zimmer
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, USA.
- Howard Hughes Medical Institute, University of Virginia, Charlottesville, VA, USA.
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3
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Wang X, Jia B, Lee K, Davis B, Wen C, Wang Y, Zheng H, Wang Y. Biomimetic Bacterial Capsule for Enhanced Aptamer Display and Cell Recognition. J Am Chem Soc 2024; 146:868-877. [PMID: 38153404 DOI: 10.1021/jacs.3c11208] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Great effort has been made to encapsulate or coat living mammalian cells for a variety of applications ranging from diabetes treatment to three-dimensional printing. However, no study has reported the synthesis of a biomimetic bacterial capsule to display high-affinity aptamers on the cell surface for enhanced cell recognition. Therefore, we synthesized an ultrathin alginate-polylysine coating to display aptamers on the surface of living cells with natural killer (NK) cells as a model. The results show that this coating-mediated aptamer display is more stable than direct cholesterol insertion into the lipid bilayer. The half-life of the aptamer on the cell surface can be increased from less than 1.5 to over 20 h. NK cells coated with the biomimetic bacterial capsule exhibit a high efficiency in recognizing and killing target cells. Therefore, this work has demonstrated a promising cell coating method for the display of aptamers for enhanced cell recognition.
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Affiliation(s)
- Xuelin Wang
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Bei Jia
- Penn State Cancer Institute, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, United States
| | - Kyungsene Lee
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Brandon Davis
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Connie Wen
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Yixun Wang
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Hong Zheng
- Penn State Cancer Institute, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, United States
| | - Yong Wang
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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4
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Kasimova AA, Sharar NS, Ambrose SJ, Knirel YA, Shneider MM, Timoshina OY, Popova AV, Perepelov AV, Dmitrenok AS, Hsu LY, Hall RM, Kenyon JJ. The Acinetobacter baumannii K70 and K9 capsular polysaccharides consist of related K-units linked by the same Wzy polymerase and cleaved by the same phage depolymerases. Microbiol Spectr 2023; 11:e0302523. [PMID: 37975684 PMCID: PMC10715181 DOI: 10.1128/spectrum.03025-23] [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: 08/03/2023] [Accepted: 10/12/2023] [Indexed: 11/19/2023] Open
Abstract
IMPORTANCE Bacteriophage show promise for the treatment of Acinetobacter baumannii infections that resist all therapeutically suitable antibiotics. Many tail-spike depolymerases encoded by phage that are able to degrade A. baumannii capsular polysaccharide (CPS) exhibit specificity for the linkage present between K-units that make up CPS polymers. This linkage is formed by a specific Wzy polymerase, and the ability to predict this linkage using sequence-based methods that identify the Wzy at the K locus could assist with the selection of phage for therapy. However, little is known about the specificity of Wzy polymerase enzymes. Here, we describe a Wzy polymerase that can accommodate two different but similar sugars as one of the residues it links and phage depolymerases that can cleave both types of bond that Wzy forms.
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Affiliation(s)
- Anastasiya A. Kasimova
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Nowshin S. Sharar
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Stephanie J. Ambrose
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, Australia
| | - Yuriy A. Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail M. Shneider
- M. M. Shemyakin and Y. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Olga Y. Timoshina
- M. M. Shemyakin and Y. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya V. Popova
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Moscow Region, Russia
| | - Andrey V. Perepelov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Andrey S. Dmitrenok
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Li Yang Hsu
- Saw Swee Hock School of Public Health, National University of Singapore, Queenstown, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Queenstown, Singapore
| | - Ruth M. Hall
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, Australia
| | - Johanna J. Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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5
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Cifuente JO, Schulze J, Bethe A, Di Domenico V, Litschko C, Budde I, Eidenberger L, Thiesler H, Ramón Roth I, Berger M, Claus H, D'Angelo C, Marina A, Gerardy-Schahn R, Schubert M, Guerin ME, Fiebig T. A multi-enzyme machine polymerizes the Haemophilus influenzae type b capsule. Nat Chem Biol 2023; 19:865-877. [PMID: 37277468 PMCID: PMC10299916 DOI: 10.1038/s41589-023-01324-3] [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: 07/13/2022] [Accepted: 03/31/2023] [Indexed: 06/07/2023]
Abstract
Bacterial capsules have critical roles in host-pathogen interactions. They provide a protective envelope against host recognition, leading to immune evasion and bacterial survival. Here we define the capsule biosynthesis pathway of Haemophilus influenzae serotype b (Hib), a Gram-negative bacterium that causes severe infections in infants and children. Reconstitution of this pathway enabled the fermentation-free production of Hib vaccine antigens starting from widely available precursors and detailed characterization of the enzymatic machinery. The X-ray crystal structure of the capsule polymerase Bcs3 reveals a multi-enzyme machine adopting a basket-like shape that creates a protected environment for the synthesis of the complex Hib polymer. This architecture is commonly exploited for surface glycan synthesis by both Gram-negative and Gram-positive pathogens. Supported by biochemical studies and comprehensive 2D nuclear magnetic resonance, our data explain how the ribofuranosyltransferase CriT, the phosphatase CrpP, the ribitol-phosphate transferase CroT and a polymer-binding domain function as a unique multi-enzyme assembly.
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Affiliation(s)
- Javier O Cifuente
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Julia Schulze
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Andrea Bethe
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Valerio Di Domenico
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain
| | - Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Lukas Eidenberger
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Hauke Thiesler
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Isabel Ramón Roth
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Monika Berger
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Heike Claus
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Cecilia D'Angelo
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Alberto Marina
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Mario Schubert
- Department of Biosciences and Medical Biology, University of Salzburg, Salzburg, Austria
| | - Marcelo E Guerin
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain.
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain.
- Ikerbasque Basque Foundation for Science, Bilbao, Spain.
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
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Doyle L, Ovchinnikova OG, Huang BS, Forrester TJB, Lowary TL, Kimber MS, Whitfield C. Mechanism and linkage specificities of the dual retaining β-Kdo glycosyltransferase modules of KpsC from bacterial capsule biosynthesis. J Biol Chem 2023; 299:104609. [PMID: 36924942 PMCID: PMC10148158 DOI: 10.1016/j.jbc.2023.104609] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 01/23/2023] [Revised: 03/09/2023] [Accepted: 03/10/2023] [Indexed: 03/15/2023] Open
Abstract
KpsC is a dual-module glycosyltransferase (GT) essential for "group 2" capsular polysaccharide biosynthesis in Escherichia coli and other Gram-negative pathogens. Capsules are vital virulence determinants in high-profile pathogens, making KpsC a viable target for intervention with small-molecule therapeutic inhibitors. Inhibitor development can be facilitated by understanding the mechanism of the target enzyme. Two separate GT modules in KpsC transfer 3-deoxy-β-d-manno-oct-2-ulosonic acid (β-Kdo) from cytidine-5'-monophospho-β-Kdo donor to a glycolipid acceptor. The N-terminal and C-terminal modules add alternating Kdo residues with β-(2→4) and β-(2→7) linkages, respectively, generating a conserved oligosaccharide core that is further glycosylated to produce diverse capsule structures. KpsC is a retaining GT, which retains the donor anomeric carbon stereochemistry. Retaining GTs typically use an SNi (substitution nucleophilic internal return) mechanism, but recent studies with WbbB, a retaining β-Kdo GT distantly related to KpsC, strongly suggest that this enzyme uses an alternative double-displacement mechanism. Based on the formation of covalent adducts with Kdo identified here by mass spectrometry and X-ray crystallography, we determined that catalytically important active site residues are conserved in WbbB and KpsC, suggesting a shared double-displacement mechanism. Additional crystal structures and biochemical experiments revealed the acceptor binding mode of the β-(2→4)-Kdo transferase module and demonstrated that acceptor recognition (and therefore linkage specificity) is conferred solely by the N-terminal α/β domain of each GT module. Finally, an Alphafold model provided insight into organization of the modules and a C-terminal membrane-anchoring region. Altogether, we identified key structural and mechanistic elements providing a foundation for targeting KpsC.
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Affiliation(s)
- Liam Doyle
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Olga G Ovchinnikova
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Bo-Shun Huang
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Taylor J B Forrester
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Todd L Lowary
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada; Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan; Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Matthew S Kimber
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada.
| | - Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada.
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7
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Timoshina OY, Kasimova AA, Shneider MM, Arbatsky NP, Shashkov AS, Shelenkov AA, Mikhailova YV, Popova AV, Hall RM, Knirel YA, Kenyon JJ. Loss of a Branch Sugar in the Acinetobacter baumannii K3-Type Capsular Polysaccharide Due To Frameshifts in the gtr6 Glycosyltransferase Gene Leads To Susceptibility To Phage APK37.1. Microbiol Spectr 2023; 11:e0363122. [PMID: 36651782 PMCID: PMC9927144 DOI: 10.1128/spectrum.03631-22] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 12/21/2022] [Indexed: 01/19/2023] Open
Abstract
The type of capsular polysaccharide (CPS) on the cell surface of Acinetobacter baumannii can determine the specificity of lytic bacteriophage under consideration for therapeutic use. Here, we report the isolation of a phage on an extensively antibiotic resistant ST2 A. baumannii isolate AB5001 that carries the KL3 CPS biosynthesis gene cluster predicting a K3-type CPS. As the phage did not infect isolates carrying KL3 or KL22 and known to produce K3 CPS, the structure of the CPS isolated from A. baumannii AB5001 was determined. AB5001 produced a variant CPS form, K3-v1, that lacks the β-d-GlсpNAc side chain attached to the d-Galp residue in the K3 structure. Inspection of the KL3 sequence in the genomes of AB5001 and other phage-susceptible isolates with a KL3 locus revealed single-base deletions in gtr6, causing loss of the Gtr6 glycosyltransferase that adds the missing d-GlсpNAc side chain to the K3 CPS. Hence, the presence of this sugar profoundly restricts the ability of the phage to digest the CPS. The 41-kb linear double-stranded DNA (dsDNA) phage genome was identical to the genome of a phage isolated on a K37-producing isolate and thus was named APK37.1. APK37.1 also infected isolates carrying KL116. Consistent with this, K3-v1 resembles the K37 and K116 structures. APK37.1 is a Friunavirus belonging to the Autographiviridae family. The phage-encoded tail spike depolymerase DpoAPK37.1 was not closely related to Dpo encoded by other sequenced Friunaviruses, including APK37 and APK116. IMPORTANCE Lytic bacteriophage have potential for the treatment of otherwise untreatable extensively antibiotic-resistant bacteria. For Acinetobacter baumannii, most phage exhibit specificity for the type of capsular polysaccharide (CPS) produced on the cell surface. However, resistance can arise via mutations in CPS genes that abolish this phage receptor. Here, we show that single-base deletions in a CPS gene result in alteration of the final structure rather than deletion of the capsule layer and hence affect the ability of a newly reported podophage to infect strains producing the K3 CPS.
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Affiliation(s)
- Olga Y. Timoshina
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya A. Kasimova
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail M. Shneider
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Nikolay P. Arbatsky
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexander S. Shashkov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | | | | | - Anastasiya V. Popova
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Russia
| | - Ruth M. Hall
- School of Life and Environmental Science, University of Sydney, Sydney, Australia
| | - Yuriy A. Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Johanna J. Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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8
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Glanville DG, Gazioglu O, Marra M, Tokars VL, Kushnir T, Habtom M, Croucher NJ, Nebenzahl YM, Mondragón A, Yesilkaya H, Ulijasz AT. Pneumococcal capsule expression is controlled through a conserved, distal cis-regulatory element during infection. PLoS Pathog 2023; 19:e1011035. [PMID: 36719895 PMCID: PMC9888711 DOI: 10.1371/journal.ppat.1011035] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 11/29/2022] [Indexed: 02/01/2023] Open
Abstract
Streptococcus pneumoniae (the pneumococcus) is the major cause of bacterial pneumonia in the US and worldwide. Studies have shown that the differing chemical make-up between serotypes of its most important virulence factor, the capsule, can dictate disease severity. Here we demonstrate that control of capsule synthesis is also critical for infection and facilitated by two broadly conserved transcription factors, SpxR and CpsR, through a distal cis-regulatory element we name the 37-CE. Strikingly, changing only three nucleotides within this sequence is sufficient to render pneumococcus avirulent. Using in vivo and in vitro approaches, we present a model where SpxR interacts as a unique trimeric quaternary structure with the 37-CE to enable capsule repression in the airways. Considering its dramatic effect on infection, variation of the 37-CE between serotypes suggests this molecular switch could be a critical contributing factor to this pathogen's serotype-specific disease outcomes.
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Affiliation(s)
- David G. Glanville
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Ozcan Gazioglu
- Department of Respiratory Sciences, University of Leicester, University Road, Leicester, United Kingdom
| | - Michela Marra
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Valerie L. Tokars
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Tatyana Kushnir
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of The Negev, Beer-Sheva, Israel
| | - Medhanie Habtom
- Department of Respiratory Sciences, University of Leicester, University Road, Leicester, United Kingdom
| | - Nicholas J. Croucher
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Sir Michael Uren Hub, Imperial College London, London, United Kingdom
| | - Yaffa Mizrachi Nebenzahl
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of The Negev, Beer-Sheva, Israel
| | - Alfonso Mondragón
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America
| | - Hasan Yesilkaya
- Department of Respiratory Sciences, University of Leicester, University Road, Leicester, United Kingdom
| | - Andrew T. Ulijasz
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, United States of America
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9
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Hurst JR, Shannon BA, Craig HC, Rishi A, Tuffs SW, McCormick JK. The Streptococcus pyogenes hyaluronic acid capsule promotes experimental nasal and skin infection by preventing neutrophil-mediated clearance. PLoS Pathog 2022; 18:e1011013. [PMID: 36449535 PMCID: PMC9744330 DOI: 10.1371/journal.ppat.1011013] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 12/12/2022] [Accepted: 11/18/2022] [Indexed: 12/05/2022] Open
Abstract
Streptococcus pyogenes is a globally prominent human-specific pathogen responsible for an enormous burden of human illnesses, including >600 million pharyngeal and >100 million skin infections each year. Despite intensive efforts that focus on invasive indications, much remains unknown about this bacterium in its natural state during colonization of the nasopharynx and skin. Using acute experimental infection models in HLA-transgenic mice, we evaluated how the hyaluronic acid (HA) capsule contributes to S. pyogenes MGAS8232 infection within these limited biological niches. Herein, we demonstrate that HA capsule expression promotes bacterial burden in murine nasal turbinates and skin lesions by resisting neutrophil-mediated killing. HA capsule production is encoded by the hasABC operon and compared to wildtype S. pyogenes infections, mice infected with a ΔhasA mutant exhibited over a 1000-fold CFU reduction at 48-hours post-nasal challenge, and a 10,000-fold CFU reduction from skin lesions 72-hours post-skin challenge. HA capsule expression contributed substantially to skin lesion size development following subdermal inoculations. In the absence of capsule expression, S. pyogenes revealed drastically impeded growth in whole human blood and increased susceptibility to killing by isolated neutrophils ex vivo, highlighting its important role in resisting phagocytosis. Furthermore, we establish that neutrophil depletion in mice recovered the reduced burden by the ΔhasA mutant in both the nasopharynx and skin. Together, this work confirms that the HA capsule is a key virulence determinant during acute infections by S. pyogenes and demonstrates that its predominant function is to protect S. pyogenes against neutrophil-mediated killing.
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Affiliation(s)
- Jacklyn R. Hurst
- Department of Microbiology and Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Blake A. Shannon
- Department of Microbiology and Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Heather C. Craig
- Department of Microbiology and Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Aanchal Rishi
- Department of Microbiology and Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Stephen W. Tuffs
- Department of Microbiology and Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - John K. McCormick
- Department of Microbiology and Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
- Lawson Health Research Institute, London, Ontario, Canada
- * E-mail:
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10
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Singh S, Wilksch JJ, Dunstan RA, Mularski A, Wang N, Hocking D, Jebeli L, Cao H, Clements A, Jenney AWJ, Lithgow T, Strugnell RA. LPS O Antigen Plays a Key Role in Klebsiella pneumoniae Capsule Retention. Microbiol Spectr 2022; 10:e0151721. [PMID: 35913154 PMCID: PMC9431683 DOI: 10.1128/spectrum.01517-21] [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: 09/13/2021] [Accepted: 06/14/2022] [Indexed: 11/24/2022] Open
Abstract
Despite the importance of encapsulation in bacterial pathogenesis, the biochemical mechanisms and forces that underpin retention of capsule by encapsulated bacteria are poorly understood. In Gram-negative bacteria, there may be interactions between lipopolysaccharide (LPS) core and capsule polymers, between capsule polymers with retained acyl carriers and the outer membrane, and in some bacteria, between the capsule polymers and Wzi, an outer membrane protein lectin. Our transposon studies in Klebsiella pneumoniae B5055 identified additional genes that, when insertionally inactivated, resulted in reduced encapsulation. Inactivation of the gene waaL, which encodes the ligase responsible for attaching the repeated O antigen of LPS to the LPS core, resulted in a significant reduction in capsule retention, measured by atomic force microscopy. This reduction in encapsulation was associated with increased sensitivity to human serum and decreased virulence in a murine model of respiratory infection and, paradoxically, with increased biofilm formation. The capsule in the WaaL mutant was physically smaller than that of the Wzi mutant of K. pneumoniae B5055. These results suggest that interactions between surface carbohydrate polymers may enhance encapsulation, a key phenotype in bacterial virulence, and provide another target for the development of antimicrobials that may avoid resistance issues associated with growth inhibition. IMPORTANCE Bacterial capsules, typically comprised of complex sugars, enable pathogens to avoid key host responses to infection, including phagocytosis. These capsules are synthesized within the bacteria, exported through the outer envelope, and then secured to the external surface of the organism by a force or forces that are incompletely described. This study shows that in the important hospital pathogen Klebsiella pneumoniae, the polysaccharide capsule is retained by interactions with other surface sugars, especially the repeated sugar molecule of the LPS molecule in Gram-negative bacteria known as "O antigen." This O antigen is joined to the LPS molecule by ligation, and loss of the enzyme responsible for ligation, a protein called WaaL, results in reduced encapsulation. Since capsules are essential to the virulence of many pathogens, WaaL might provide a target for new antimicrobial development, critical to the control of pathogens like K. pneumoniae that have become highly drug resistant.
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Affiliation(s)
- Shweta Singh
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Jonathan J. Wilksch
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Rhys A. Dunstan
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Anna Mularski
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Nancy Wang
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Dianna Hocking
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Leila Jebeli
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Hanwei Cao
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Abigail Clements
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Adam W. J. Jenney
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Trevor Lithgow
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Richard A. Strugnell
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
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11
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Allué-Guardia A, Garcia-Vilanova A, Olmo-Fontánez AM, Peters J, Maselli DJ, Wang Y, Turner J, Schlesinger LS, Torrelles JB. Host- and Age-Dependent Transcriptional Changes in Mycobacterium tuberculosis Cell Envelope Biosynthesis Genes after Exposure to Human Alveolar Lining Fluid. Int J Mol Sci 2022; 23:ijms23020983. [PMID: 35055170 PMCID: PMC8780516 DOI: 10.3390/ijms23020983] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [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: 12/07/2021] [Revised: 01/09/2022] [Accepted: 01/10/2022] [Indexed: 12/16/2022] Open
Abstract
Tuberculosis (TB) infection, caused by the airborne pathogen Mycobacterium tuberculosis (M.tb), resulted in almost 1.4 million deaths in 2019, and the number of deaths is predicted to increase by 20% over the next 5 years due to the COVID-19 pandemic. Upon reaching the alveolar space, M.tb comes into close contact with the lung mucosa before and after its encounter with host alveolar compartment cells. Our previous studies show that homeostatic, innate soluble components of the alveolar lining fluid (ALF) can quickly alter the cell envelope surface of M.tb upon contact, defining subsequent M.tb-host cell interactions and infection outcomes in vitro and in vivo. We also demonstrated that ALF from 60+ year old elders (E-ALF) vs. healthy 18- to 45-year-old adults (A-ALF) is dysfunctional, with loss of homeostatic capacity and impaired innate soluble responses linked to high local oxidative stress. In this study, a targeted transcriptional assay shows that M.tb exposure to human ALF alters the expression of its cell envelope genes. Specifically, our results indicate that A-ALF-exposed M.tb upregulates cell envelope genes associated with lipid, carbohydrate, and amino acid metabolism, as well as genes associated with redox homeostasis and transcriptional regulators. Conversely, M.tb exposure to E-ALF shows a lesser transcriptional response, with most of the M.tb genes unchanged or downregulated. Overall, this study indicates that M.tb responds and adapts to the lung alveolar environment upon contact, and that the host ALF status, determined by factors such as age, might play an important role in determining infection outcome.
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Affiliation(s)
- Anna Allué-Guardia
- Population Health Program, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (A.G.-V.); (A.M.O.-F.)
- Correspondence: (A.A.-G.); (J.B.T.)
| | - Andreu Garcia-Vilanova
- Population Health Program, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (A.G.-V.); (A.M.O.-F.)
| | - Angélica M. Olmo-Fontánez
- Population Health Program, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (A.G.-V.); (A.M.O.-F.)
- Integrated Biomedical Sciences Program, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Jay Peters
- Division of Pulmonary and Critical Care Medicine, School of Medicine, UT Health San Antonio, San Antonio, TX 78229, USA; (J.P.); (D.J.M.)
| | - Diego J. Maselli
- Division of Pulmonary and Critical Care Medicine, School of Medicine, UT Health San Antonio, San Antonio, TX 78229, USA; (J.P.); (D.J.M.)
| | - Yufeng Wang
- Department of Molecular Microbiology and Immunology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA;
| | - Joanne Turner
- Host-Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (J.T.); (L.S.S.)
| | - Larry S. Schlesinger
- Host-Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (J.T.); (L.S.S.)
| | - Jordi B. Torrelles
- Population Health Program, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (A.G.-V.); (A.M.O.-F.)
- Correspondence: (A.A.-G.); (J.B.T.)
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12
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Ku H, Kabwe M, Chan HT, Stanton C, Petrovski S, Batinovic S, Tucci J. Novel Drexlerviridae bacteriophage KMI8 with specific lytic activity against Klebsiella michiganensis and its biofilms. PLoS One 2021; 16:e0257102. [PMID: 34492081 PMCID: PMC8423285 DOI: 10.1371/journal.pone.0257102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 03/05/2021] [Accepted: 08/23/2021] [Indexed: 11/25/2022] Open
Abstract
The bacterial genus Klebsiella includes the closely related species K. michiganensis, K. oxytoca and K. pneumoniae, which are capable of causing severe disease in humans. In this report we describe the isolation, genomic and functional characterisation of the lytic bacteriophage KMI8 specific for K. michiganensis. KMI8 belongs to the family Drexlerviridae, and has a novel genome which shares very little homology (71.89% identity over a query cover of only 8%) with that of its closest related bacteriophages (Klebsiella bacteriophage LF20 (MW417503.1); Klebsiella bacteriophage 066039 (MW042802.1). KMI8, which possess a putative endosialidase (depolymerase) enzyme, was shown to be capable of degrading mono-biofilms of a strain of K. michiganensis that carried the polysaccharide capsule KL70 locus. This is the first report of a lytic bacteriophage for K. michiganensis, which is capable of breaking down a biofilm of this species.
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Affiliation(s)
- Heng Ku
- Department of Pharmacy and Biomedical Science, La Trobe Institute for Molecular Science, La Trobe University, Victoria, Australia
| | - Mwila Kabwe
- Department of Pharmacy and Biomedical Science, La Trobe Institute for Molecular Science, La Trobe University, Victoria, Australia
| | - Hiu Tat Chan
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Victoria, Australia
- Department of Microbiology, Royal Melbourne Hospital, Victoria, Australia
| | - Cassandra Stanton
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Victoria, Australia
| | - Steve Petrovski
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Victoria, Australia
| | - Steven Batinovic
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Victoria, Australia
| | - Joseph Tucci
- Department of Pharmacy and Biomedical Science, La Trobe Institute for Molecular Science, La Trobe University, Victoria, Australia
- * E-mail:
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13
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Dunstan RA, Bamert RS, Belousoff MJ, Short FL, Barlow CK, Pickard DJ, Wilksch JJ, Schittenhelm RB, Strugnell RA, Dougan G, Lithgow T. Mechanistic Insights into the Capsule-Targeting Depolymerase from a Klebsiella pneumoniae Bacteriophage. Microbiol Spectr 2021; 9:e0102321. [PMID: 34431721 PMCID: PMC8552709 DOI: 10.1128/spectrum.01023-21] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [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: 07/27/2021] [Accepted: 08/02/2021] [Indexed: 02/07/2023] Open
Abstract
The production of capsular polysaccharides by Klebsiella pneumoniae protects the bacterial cell from harmful environmental factors such as antimicrobial compounds and infection by bacteriophages (phages). To bypass this protective barrier, some phages encode polysaccharide-degrading enzymes referred to as depolymerases to provide access to cell surface receptors. Here, we characterized the phage RAD2, which infects K. pneumoniae strains that produce the widespread, hypervirulence-associated K2-type capsular polysaccharide. Using transposon-directed insertion sequencing, we have shown that the production of capsule is an absolute requirement for efficient RAD2 infection by serving as a first-stage receptor. We have identified the depolymerase responsible for recognition and degradation of the capsule, determined that the depolymerase forms globular appendages on the phage virion tail tip, and present the cryo-electron microscopy structure of the RAD2 capsule depolymerase at 2.7-Å resolution. A putative active site for the enzyme was identified, comprising clustered negatively charged residues that could facilitate the hydrolysis of target polysaccharides. Enzymatic assays coupled with mass spectrometric analyses of digested oligosaccharide products provided further mechanistic insight into the hydrolase activity of the enzyme, which, when incubated with K. pneumoniae, removes the capsule and sensitizes the cells to serum-induced killing. Overall, these findings expand our understanding of how phages target the Klebsiella capsule for infection, providing a framework for the use of depolymerases as antivirulence agents against this medically important pathogen. IMPORTANCE Klebsiella pneumoniae is a medically important pathogen that produces a thick protective capsule that is essential for pathogenicity. Phages are natural predators of bacteria, and many encode diverse "capsule depolymerases" which specifically degrade the capsule of their hosts, an exploitable trait for potential therapies. We have determined the first structure of a depolymerase that targets the clinically relevant K2 capsule and have identified its putative active site, providing hints to its mechanism of action. We also show that Klebsiella cells treated with a recombinant form of the depolymerase are stripped of capsule, inhibiting their ability to grow in the presence of serum, demonstrating the anti-infective potential of these robust and readily producible enzymes against encapsulated bacterial pathogens such as K. pneumoniae.
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Affiliation(s)
- Rhys A. Dunstan
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
- Centre to Impact AMR, Monash University, Clayton, Australia
| | - Rebecca S. Bamert
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
- Centre to Impact AMR, Monash University, Clayton, Australia
| | - Matthew J. Belousoff
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Francesca L. Short
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
- Wellcome Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Christopher K. Barlow
- Monash Proteomics & Metabolomics Facility, Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Derek J. Pickard
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Jonathan J. Wilksch
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
- Centre to Impact AMR, Monash University, Clayton, Australia
| | - Ralf B. Schittenhelm
- Monash Proteomics & Metabolomics Facility, Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Richard A. Strugnell
- Department of Microbiology and Immunology, The Peter Doherty Institute, The University of Melbourne, Parkville, Australia
| | - Gordon Dougan
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Trevor Lithgow
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
- Centre to Impact AMR, Monash University, Clayton, Australia
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14
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Haudiquet M, Buffet A, Rendueles O, Rocha EPC. Interplay between the cell envelope and mobile genetic elements shapes gene flow in populations of the nosocomial pathogen Klebsiella pneumoniae. PLoS Biol 2021; 19:e3001276. [PMID: 34228700 PMCID: PMC8259999 DOI: 10.1371/journal.pbio.3001276] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 05/07/2021] [Indexed: 01/01/2023] Open
Abstract
Mobile genetic elements (MGEs) drive genetic transfers between bacteria using mechanisms that require a physical interaction with the cellular envelope. In the high-priority multidrug-resistant nosocomial pathogens (ESKAPE), the first point of contact between the cell and virions or conjugative pili is the capsule. While the capsule can be a barrier to MGEs, it also evolves rapidly by horizontal gene transfer (HGT). Here, we aim at understanding this apparent contradiction by studying the covariation between the repertoire of capsule genes and MGEs in approximately 4,000 genomes of Klebsiella pneumoniae (Kpn). We show that capsules drive phage-mediated gene flow between closely related serotypes. Such serotype-specific phage predation also explains the frequent inactivation of capsule genes, observed in more than 3% of the genomes. Inactivation is strongly epistatic, recapitulating the capsule biosynthetic pathway. We show that conjugative plasmids are acquired at higher rates in natural isolates lacking a functional capsular locus and confirmed experimentally this result in capsule mutants. This suggests that capsule inactivation by phage pressure facilitates its subsequent reacquisition by conjugation. Accordingly, capsule reacquisition leaves long recombination tracts around the capsular locus. The loss and regain process rewires gene flow toward other lineages whenever it leads to serotype swaps. Such changes happen preferentially between chemically related serotypes, hinting that the fitness of serotype-swapped strains depends on the host genetic background. These results enlighten the bases of trade-offs between the evolution of virulence and multidrug resistance and caution that some alternatives to antibiotics by selecting for capsule inactivation may facilitate the acquisition of antibiotic resistance genes (ARGs). A study of how the complex interaction between capsules and mobile genetic elements shapes gene flow in populations of Klebsiella pneumoniae reveals that capsule inactivation by phage pressure facilitates its subsequent re-acquisition by conjugation, and this loss and re-gain process influences the gene flow towards other lineages whenever it leads to serotype changes.
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Affiliation(s)
- Matthieu Haudiquet
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, Paris, France
- Ecole Doctoral FIRE–Programme Bettencourt, CRI, Paris, France
- * E-mail:
| | - Amandine Buffet
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, Paris, France
| | - Olaya Rendueles
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, Paris, France
| | - Eduardo P. C. Rocha
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, Paris, France
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15
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Eichner H, Karlsson J, Spelmink L, Pathak A, Sham LT, Henriques-Normark B, Loh E. RNA thermosensors facilitate Streptococcus pneumoniae and Haemophilus influenzae immune evasion. PLoS Pathog 2021; 17:e1009513. [PMID: 33914847 PMCID: PMC8084184 DOI: 10.1371/journal.ppat.1009513] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 03/29/2021] [Indexed: 11/18/2022] Open
Abstract
Bacterial meningitis is a major cause of death and disability in children worldwide. Two human restricted respiratory pathogens, Streptococcus pneumoniae and Haemophilus influenzae, are the major causative agents of bacterial meningitis, attributing to 200,000 deaths annually. These pathogens are often part of the nasopharyngeal microflora of healthy carriers. However, what factors elicit them to disseminate and cause invasive diseases, remain unknown. Elevated temperature and fever are hallmarks of inflammation triggered by infections and can act as warning signals to pathogens. Here, we investigate whether these respiratory pathogens can sense environmental temperature to evade host complement-mediated killing. We show that productions of two vital virulence factors and vaccine components, the polysaccharide capsules and factor H binding proteins, are temperature dependent, thus influencing serum/opsonophagocytic killing of the bacteria. We identify and characterise four novel RNA thermosensors in S. pneumoniae and H. influenzae, responsible for capsular biosynthesis and production of factor H binding proteins. Our data suggest that these bacteria might have independently co-evolved thermosensing abilities with different RNA sequences but distinct secondary structures to evade the immune system.
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Affiliation(s)
- Hannes Eichner
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
| | - Jens Karlsson
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
| | - Laura Spelmink
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
| | - Anuj Pathak
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
| | - Lok-To Sham
- Infectious Disease Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Birgitta Henriques-Normark
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
- Clinical Microbiology, Bioclinicum, Karolinska University Hospital, Solna, Sweden
- Lee Kong Chian School of Medicine and Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Edmund Loh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
- Clinical Microbiology, Bioclinicum, Karolinska University Hospital, Solna, Sweden
- Lee Kong Chian School of Medicine and Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
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16
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Fiebig T, Cramer JT, Bethe A, Baruch P, Curth U, Führing JI, Buettner FFR, Vogel U, Schubert M, Fedorov R, Mühlenhoff M. Structural and mechanistic basis of capsule O-acetylation in Neisseria meningitidis serogroup A. Nat Commun 2020; 11:4723. [PMID: 32948778 PMCID: PMC7501274 DOI: 10.1038/s41467-020-18464-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [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: 07/24/2020] [Accepted: 08/20/2020] [Indexed: 02/08/2023] Open
Abstract
O-Acetylation of the capsular polysaccharide (CPS) of Neisseria meningitidis serogroup A (NmA) is critical for the induction of functional immune responses, making this modification mandatory for CPS-based anti-NmA vaccines. Using comprehensive NMR studies, we demonstrate that O-acetylation stabilizes the labile anomeric phosphodiester-linkages of the NmA-CPS and occurs in position C3 and C4 of the N-acetylmannosamine units due to enzymatic transfer and non-enzymatic ester migration, respectively. To shed light on the enzymatic transfer mechanism, we solved the crystal structure of the capsule O-acetyltransferase CsaC in its apo and acceptor-bound form and of the CsaC-H228A mutant as trapped acetyl-enzyme adduct in complex with CoA. Together with the results of a comprehensive mutagenesis study, the reported structures explain the strict regioselectivity of CsaC and provide insight into the catalytic mechanism, which relies on an unexpected Gln-extension of a classical Ser-His-Asp triad, embedded in an α/β-hydrolase fold.
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Affiliation(s)
- Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
| | | | - Andrea Bethe
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Petra Baruch
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Jana I Führing
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
- Fraunhofer International Consortium for Anti-Infective Research (iCAIR), Hannover, Germany
| | - Falk F R Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Ulrich Vogel
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Mario Schubert
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Roman Fedorov
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Martina Mühlenhoff
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
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17
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Porter NT, Hryckowian AJ, Merrill BD, Fuentes JJ, Gardner JO, Glowacki RWP, Singh S, Crawford RD, Snitkin ES, Sonnenburg JL, Martens EC. Phase-variable capsular polysaccharides and lipoproteins modify bacteriophage susceptibility in Bacteroides thetaiotaomicron. Nat Microbiol 2020; 5:1170-1181. [PMID: 32601452 PMCID: PMC7482406 DOI: 10.1038/s41564-020-0746-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [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: 01/15/2019] [Accepted: 05/27/2020] [Indexed: 12/22/2022]
Abstract
A variety of cell surface structures dictate interactions between bacteria and their environment, including their viruses (bacteriophages). Members of the human gut Bacteroidetes characteristically produce several phase-variable capsular polysaccharides (CPSs), but their contributions to bacteriophage interactions are unknown. To begin to understand how CPSs have an impact on Bacteroides-phage interactions, we isolated 71 Bacteroides thetaiotaomicron-infecting bacteriophages from two locations in the United States. Using B. thetaiotaomicron strains that express defined subsets of CPSs, we show that CPSs dictate host tropism for these phages and that expression of non-permissive CPS variants is selected under phage predation, enabling survival. In the absence of CPSs, B. thetaiotaomicron escapes bacteriophage predation by altering expression of eight distinct phase-variable lipoproteins. When constitutively expressed, one of these lipoproteins promotes resistance to multiple bacteriophages. Our results reveal important roles for Bacteroides CPSs and other cell surface structures that allow these bacteria to persist under bacteriophage predation, and hold important implications for using bacteriophages therapeutically to target gut symbionts.
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Affiliation(s)
- Nathan T Porter
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA
| | - Andrew J Hryckowian
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA.
| | - Bryan D Merrill
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
| | - Jaime J Fuentes
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA
| | - Jackson O Gardner
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
| | - Robert W P Glowacki
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA
| | - Shaleni Singh
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA
| | - Ryan D Crawford
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Evan S Snitkin
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA
| | - Justin L Sonnenburg
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
| | - Eric C Martens
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA.
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18
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Abstract
Francisella tularensis is a tier 1 select agent responsible for tularemia in humans and a wide variety of animal species. Extensive research into understanding the virulence factors of the bacterium has been ongoing to develop an efficacious vaccine. At least two such virulence factors are described as capsules of F. tularensis: the O-antigen capsule and the capsule-like complex (CLC). These two separate entities aid in avoiding host immune defenses but have not been clearly differentiated. These components are distinct and differ in composition and genetic basis. The O-antigen capsule consists of a polysaccharide nearly identical to the lipopolysaccharide (LPS) O antigen, whereas the CLC is a heterogeneous complex of glycoproteins, proteins, and possibly outer membrane vesicles and tubes (OMV/Ts). In this review, the current understanding of these two capsules is summarized, and the historical references to "capsules" of F. tularensis are clarified. A significant amount of research has been invested into the composition of each capsule and the genes involved in synthesis of the polysaccharide portion of each capsule. Areas of future research include further exploration into the molecular regulation and pathways responsible for expression of each capsule and further elucidating the role that each capsule plays in virulence.
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Affiliation(s)
- Kelly C Freudenberger Catanzaro
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - Thomas J Inzana
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA
- College of Veterinary Medicine, Long Island University, Brookville, New York, USA
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19
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Budde I, Litschko C, Führing JI, Gerardy-Schahn R, Schubert M, Fiebig T. An enzyme-based protocol for cell-free synthesis of nature-identical capsular oligosaccharides from Actinobacillus pleuropneumoniae serotype 1. J Biol Chem 2020; 295:5771-5784. [PMID: 32152227 PMCID: PMC7186170 DOI: 10.1074/jbc.ra120.012961] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 02/14/2020] [Revised: 03/09/2020] [Indexed: 11/06/2022] Open
Abstract
Actinobacillus pleuropneumoniae (App) is the etiological agent of acute porcine pneumonia and responsible for severe economic losses worldwide. The capsule polymer of App serotype 1 (App1) consists of [4)-GlcNAc-β(1,6)-Gal-α-1-(PO4-] repeating units that are O-acetylated at O-6 of the GlcNAc. It is a major virulence factor and was used in previous studies in the successful generation of an experimental glycoconjugate vaccine. However, the application of glycoconjugate vaccines in the animal health sector is limited, presumably because of the high costs associated with harvesting the polymer from pathogen culture. Consequently, here we exploited the capsule polymerase Cps1B of App1 as an in vitro synthesis tool and an alternative for capsule polymer provision. Cps1B consists of two catalytic domains, as well as a domain rich in tetratricopeptide repeats (TPRs). We compared the elongation mechanism of Cps1B with that of a ΔTPR truncation (Cps1B-ΔTPR). Interestingly, the product profiles displayed by Cps1B suggested processive elongation of the nascent polymer, whereas Cps1B-ΔTPR appeared to work in a more distributive manner. The dispersity of the synthesized products could be reduced by generating single-action transferases and immobilizing them on individual columns, separating the two catalytic activities. Furthermore, we identified the O-acetyltransferase Cps1D of App1 and used it to modify the polymers produced by Cps1B. Two-dimensional NMR analyses of the products revealed O-acetylation levels identical to those of polymer harvested from App1 culture supernatants. In conclusion, we have established a protocol for the pathogen-free in vitro synthesis of tailored, nature-identical App1 capsule polymers.
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Affiliation(s)
- Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | - Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | - Jana I Führing
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany; Fraunhofer International Consortium for Anti-Infective Research (iCAIR), 30625 Hannover, Germany
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany; Fraunhofer International Consortium for Anti-Infective Research (iCAIR), 30625 Hannover, Germany
| | - Mario Schubert
- Department of Biosciences, University of Salzburg, 5020 Salzburg, Austria
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany.
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20
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Hsieh S, Porter NT, Donermeyer DL, Horvath S, Strout G, Saunders BT, Zhang N, Zinselmeyer B, Martens EC, Stappenbeck TS, Allen PM. Polysaccharide Capsules Equip the Human Symbiont Bacteroides thetaiotaomicron to Modulate Immune Responses to a Dominant Antigen in the Intestine. J Immunol 2020; 204:1035-1046. [PMID: 31900343 PMCID: PMC7002182 DOI: 10.4049/jimmunol.1901206] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 11/26/2019] [Indexed: 01/12/2023]
Abstract
Bacteria express multiple diverse capsular polysaccharides (CPSs) for protection against environmental and host factors, including the host immune system. Using a mouse TCR transgenic CD4+ T cell, BθOM, that is specific for B. thetaiotaomicron and a complete set of single CPS-expressing B. thetaiotaomicron strains, we ask whether CPSs can modify the immune responses to specific bacterial Ags. Acapsular B. thetaiotaomicron, which lacks all B. thetaiotaomicron CPSs, stimulated BθOM T cells more strongly than wild-type B. thetaiotaomicron Despite similar levels of BθOM Ag expression, many single CPS-expressing B. thetaiotaomicron strains were antistimulatory and weakly activated BθOM T cells, but a few strains were prostimulatory and strongly activated BθOM T cells just as well or better than an acapsular strain. B. thetaiotaomicron strains that expressed an antistimulatory CPS blocked Ag delivery to the immune system, which could be rescued by Fc receptor-dependent Ab opsonization. All single CPS-expressing B. thetaiotaomicron strains stimulated the innate immune system to skew toward M1 macrophages and release inflammatory cytokines in an MyD88-dependent manner, with antistimulatory CPS activating the innate immune system in a weaker manner than prostimulatory CPS. The expression of antistimulatory versus prostimulatory CPSs on outer membrane vesicles also regulated immune responses. Moreover, antistimulatory and prostimulatory single CPS-expressing B. thetaiotaomicron strains regulated the activation of Ag-specific and polyclonal T cells as well as clearance of dominant Ag in vivo. These studies establish that the immune responses to specific bacterial Ags can be modulated by a diverse set of CPSs.
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Affiliation(s)
- Samantha Hsieh
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Nathan T Porter
- Division of Industrial Biotechnology, Chalmers University of Technology, Gothenburg, SE-412 96 Sweden
| | - David L Donermeyer
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Stephen Horvath
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Gregory Strout
- Washington University Center for Cellular Imaging, Washington University School of Medicine, St. Louis, MO 63110; and
| | - Brian T Saunders
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Nan Zhang
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Bernd Zinselmeyer
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Eric C Martens
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Thaddeus S Stappenbeck
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Paul M Allen
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
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21
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Chen Z, Sun X, Chen Q, Lan T, Huang K, Xiao H, Lin Z, Yang Y, Liu P, Huang H. Connexin32 ameliorates renal fibrosis in diabetic mice by promoting K48-linked NADPH oxidase 4 polyubiquitination and degradation. Br J Pharmacol 2020; 177:145-160. [PMID: 31465542 PMCID: PMC6976783 DOI: 10.1111/bph.14853] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/25/2019] [Accepted: 08/22/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND PURPOSE Nox4 is the major isoform of NADPH oxidase found in the kidney and contributes to the pathogenesis of diabetic nephropathy. However, the molecular mechanisms of increased Nox4 expression induced by hyperglycaemia remain to be elucidated. Here, the role of the connexin32-Nox4 signalling axis in diabetic nephropathy and its related mechanisms were investigated. EXPERIMENTAL APPROACH Diabetes was induced in mice by low-dose streptozotocin (STZ) combined with a high-fat diet. Effects of connexin32 on Nox4 expression and on renal function and fibrosis in STZ-induced diabetic mice were investigated using adenovirus-overexpressing connexin32 and connexin32-deficient mice. Interactions between connexin32 and Nox4 were analysed by co-immunoprecipitation and immunofluorescence assays. KEY RESULTS Connexin32 was down-regulated in the kidneys of STZ-induced diabetic mice. Overexpression of connexin32 reduced expression of Nox4 and improved renal function and fibrosis in diabetic mice, whereas connexin32 deficiency had opposite effects. Down-regulation of fibronectin expression by connexin32 was not dependent on gap junctional intercellular communication involving connexin32. Connexin32 interacted with Nox4 and reduced the generation of hydrogen peroxide, leading to the down-regulation of fibronectin expression. Mechanistically, connexin32 decreased Nox4 expression by promoting its K48-linked polyubiquitination. Interestingly, Smurf1 overexpression inhibited K48-linked polyubiquitination of Nox4. Furthermore, connexin32 interacted with Smurf1 and inhibited its expression. CONCLUSION AND IMPLICATIONS Connexin32 ameliorated renal fibrosis in diabetic mice by promoting K48-linked Nox4 polyubiquitination and degradation via inhibition of Smurf1 expression. Targeting the connexin32-Nox4 signalling axis may contribute to the development of novel treatments for diabetic nephropathy.
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Affiliation(s)
- Zhiquan Chen
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
- Department of Pharmacology, School of PharmacyGuangxi Medical UniversityNanningChina
- Guangdong Provincial Key Laboratory of New Drug Design and EvaluationSun Yat‐sen UniversityGuangzhouChina
| | - Xiaohong Sun
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
- Guangdong Provincial Key Laboratory of New Drug Design and EvaluationSun Yat‐sen UniversityGuangzhouChina
| | - Qiuhong Chen
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
| | - Tian Lan
- Department of Pharmacology, School of PharmacyGuangdong Pharmaceutical UniversityGuangzhouChina
| | - Kaipeng Huang
- Guangzhou Eighth People's HospitalGuangzhou Medical UniversityGuangzhouChina
| | - Haiming Xiao
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
| | - Zeyuan Lin
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
| | - Yan Yang
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
| | - Peiqing Liu
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
| | - Heqing Huang
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical SciencesSun Yat‐sen UniversityGuangzhouChina
- Guangdong Provincial Key Laboratory of New Drug Design and EvaluationSun Yat‐sen UniversityGuangzhouChina
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22
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Del Bino L, Calloni I, Oldrini D, Raso MM, Cuffaro R, Ardá A, Codée JDC, Jiménez‐Barbero J, Adamo R. Regioselective Glycosylation Strategies for the Synthesis of Group Ia and Ib Streptococcus Related Glycans Enable Elucidating Unique Conformations of the Capsular Polysaccharides. Chemistry 2019; 25:16277-16287. [PMID: 31506992 PMCID: PMC6972993 DOI: 10.1002/chem.201903527] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [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: 08/02/2019] [Revised: 09/07/2019] [Indexed: 12/29/2022]
Abstract
Group B Streptococcus serotypes Ia and Ib capsular polysaccharides are key targets for vaccine development. In spite of their immunospecifity these polysaccharides share high structural similarity. Both are composed of the same monosaccharide residues and differ only in the connection of the Neu5Acα2-3Gal side chain to the GlcNAc unit, which is a β1-4 linkage in serotype Ia and a β1-3 linkage in serotype Ib. The development of efficient regioselective routes for GlcNAcβ1-3[Glcβ1-4]Gal synthons is described, which give access to different group B Streptococcus (GBS) Ia and Ib repeating unit frameshifts. These glycans were used to probe the conformation and molecular dynamics of the two polysaccharides, highlighting the different presentation of the protruding Neu5Acα2-3Gal moieties on the polysaccharide backbones and a higher flexibility of Ib polymer relative to Ia, which can impact epitope exposure.
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Affiliation(s)
| | - Ilaria Calloni
- CIC bioGUNEBizkaia Technology Park, Building 80048160DerioSpain
| | | | | | | | - Ana Ardá
- CIC bioGUNEBizkaia Technology Park, Building 80048160DerioSpain
| | - Jeroen D. C. Codée
- Department of Bioorganic SynthesisLeiden University2333LeidenThe Netherlands
| | - Jesús Jiménez‐Barbero
- CIC bioGUNEBizkaia Technology Park, Building 80048160DerioSpain
- Basque Foundation for Science IKERBASQUE8009BilbaoSpain
- Department of Organic Chemistry IIFaculty of Science and TechnologyUniversity of the Basque Country48940LeioaSpain
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23
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Nanayakkara BS, O'Brien CL, Gordon DM. Phenotypic characteristics contributing to the enhanced growth of Escherichia coli bloom strains. Environ Microbiol Rep 2019; 11:817-824. [PMID: 31642169 DOI: 10.1111/1758-2229.12801] [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] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 10/18/2019] [Indexed: 06/10/2023]
Abstract
During bloom events, Escherichia coli cell counts increase to between 10,000 and 100,000 cfu/100 ml of water. The strains responsible for bloom events belong to E. coli phylogenetic groups A and B1, and all have acquired a capsule from Klebsiella. A pan-genome comparison of phylogroup A E. coli revealed that the ferric citrate uptake system (fecIRABCDE) was overrepresented in phylogroup A bloom strains compared with non-bloom E. coli. A series of experiments were carried out to investigate if the capsule together with ferric citrate uptake system could confer a growth rate advantage on E. coli. Capsulated strains had a growth rate advantage regardless of the media composition and the presence/absence of the fec operon, and they had a shorter lag phase compared with capsule-negative strains. The results suggest that the Klebsiella capsule may facilitate nutrient uptake or utilization by a strain. This, together with the protective roles played by the capsule and the shorter lag phase of capsule-positive strains, may explain why it is only capsule-positive strains that produce elevated counts in response to nutrient influx.
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Affiliation(s)
- Buddhie S Nanayakkara
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, RN Robertson Building, 46 Sullivans Creek Road, Canberra, ACT, 2601, Australia
- Department of Botany, Faculty of Science, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - Claire L O'Brien
- Medical School, The Australian National University, Canberra, ACT, 2601, Australia
- Gastroenterology and Hepatology Unit, Canberra Hospital, Canberra, ACT, Australia
| | - David M Gordon
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, RN Robertson Building, 46 Sullivans Creek Road, Canberra, ACT, 2601, Australia
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24
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Auger JP, Payen S, Roy D, Dumesnil A, Segura M, Gottschalk M. Interactions of Streptococcus suis serotype 9 with host cells and role of the capsular polysaccharide: Comparison with serotypes 2 and 14. PLoS One 2019; 14:e0223864. [PMID: 31600314 PMCID: PMC6786723 DOI: 10.1371/journal.pone.0223864] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [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: 07/04/2019] [Accepted: 09/30/2019] [Indexed: 12/21/2022] Open
Abstract
Streptococcus suis is an important porcine bacterial pathogen and a zoonotic agent responsible for sudden death, septic shock and meningitis, of which serotype 2 is the most widespread, with serotype 14 also causing infections in humans in South-East Asia. Knowledge of its pathogenesis and virulence are almost exclusively based on these two serotypes. Though serotype 9 is responsible for the greatest number of porcine cases in Spain, the Netherlands and Germany, very little information is currently available regarding this serotype. Of the different virulence factors, the capsular polysaccharide (CPS) is required for S. suis virulence as it promotes resistance to phagocytosis and killing and masks surface components responsible for host cell activation. However, these roles have been described for serotypes 2 and 14, whose CPSs are structurally and compositionally similar, both containing sialic acid. Consequently, we evaluated herein the interactions of serotype 9 with host cells and the role of its CPS, which greatly differs from those of serotypes 2 and 14. Results demonstrated that serotype 9 adhesion to but not invasion of respiratory epithelial cells was greater than that of serotypes 2 and 14. Furthermore serotype 9 was more internalized by macrophages but equally resistant to whole blood killing. Though recognition of serotypes 2, 9 and 14 by DCs required MyD88-dependent signaling, in vitro pro-inflammatory mediator production induced by serotype 9 was much lower. In vivo, however, serotype 9 causes an exacerbated inflammatory response, which combined with persistent bacterial presence, is probably responsible for host death during the systemic infection. Though presence of the serotype 9 CPS masks surface components less efficiently than those of serotypes 2 and 14, the serotype 9 CPS remains critical for virulence as it is required for survival in blood and development of clinical disease, and this regardless of its unique composition and structure.
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Affiliation(s)
- Jean-Philippe Auger
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, Quebec, Canada
| | - Servane Payen
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, Quebec, Canada
| | - David Roy
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, Quebec, Canada
| | - Audrey Dumesnil
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, Quebec, Canada
| | - Mariela Segura
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, Quebec, Canada
| | - Marcelo Gottschalk
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, Quebec, Canada
- * E-mail:
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25
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Erenler AS. Capsular Polysaccharide Biosynthesis from Recombinant E. coli and Chondroitin Sülfate Production. Cell Mol Biol (Noisy-le-grand) 2019; 65:17-21. [PMID: 31472043] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 07/25/2019] [Accepted: 07/19/2019] [Indexed: 06/10/2023]
Abstract
Chondroitin sulfate (CS) is an important biomedical product. CS is the basic structural component of the mammalian extracellular matrix and is widely used in many applications in the fields of medicine, veterinary medicine, pharmaceuticals and cosmetics. For CS production, mainly animal sources are used. However, in today's conditions, due to various risks and artificial synthesis, there has been an increase in alternative sources of production methods for CS, instead of using animal resources. In this study as a powerful alternative microbial production of CS has been targeted. By using recombinant E. coli strains to integrate VHb /vgb+ and kfo+ systems, the aim was to obtain high purity CS from reliable biotechnological processes. Plasmid pUC8:15 bearing the vgb gene region, and plasmid pETM6-PACF carrying the kfoA, kfoC and kfoF genes responsible for chondroitin synthesis, were transferred to E. coli bacteria. Microbial CS was obtained by adding sulfate groups to chondroitin acquired after the treatments. The results were confirmed by HPLC and NMR analyses. The product, compared to its counterparts, was found to be an effective drug, potentially with a low molecular weight value.
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26
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Kenyon JJ, Arbatsky NP, Shneider MM, Popova AV, Dmitrenok AS, Kasimova AA, Shashkov AS, Hall RM, Knirel YA. The K46 and K5 capsular polysaccharides produced by Acinetobacter baumannii NIPH 329 and SDF have related structures and the side-chain non-ulosonic acids are 4-O-acetylated by phage-encoded O-acetyltransferases. PLoS One 2019; 14:e0218461. [PMID: 31220143 PMCID: PMC6586298 DOI: 10.1371/journal.pone.0218461] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [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: 03/28/2019] [Accepted: 06/03/2019] [Indexed: 12/01/2022] Open
Abstract
Acinetobacter baumannii isolate NIPH 329 carries a novel capsular polysaccharide (CPS) gene cluster, designated KL46, that is closely related to the KL5 locus in A. baumannii isolate SDF but includes genes for synthesis of 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic (di-N-acetylpseudaminic) acid (Pse5Ac7Ac) instead of the corresponding D-glycero-D-galacto isomer (di-N-acetyllegionaminic acid) (Leg5Ac7Ac). In agreement with the genetic content of KL46, chemical studies of the K46 CPS produced by NIPH 329 revealed a branched tetrasaccharide repeat (K unit) with an overall structure the same as K5 from SDF but with â-Pse5Ac7Ac replacing α-Leg5Ac7Ac. As for K5, the K46 unit begins with d-GalpNAc and includes α-d-GlcpNAc-(1→3)-d-GalpNAc and α-d-Galp-(1→6)-d-GlcpNAc linkages, formed by Gtr14 and Gtr15 glycosyltransferases, respectively. The Gtr94K46 glycosyltransferase, which is related to Gtr13K5, links Pse5Ac7Ac to d-Galp in the growing K unit via a â-(2→6) linkage. Nearly identical Wzy enzymes connect the K46 and K5 units via a α-D-GalpNAc-(1→3)-α-D-Galp linkage to form closely related CPSs. Both Pse5Ac7Ac in K46 and Leg5Ac7Ac in K5 are acetylated at O4 but no acetyltransferase gene is present in KL46 or KL5. Related acetyltransferases were found encoded in the NIPH 329 and SDF genomes, but not in other strains carrying an unacetylated Pse or Leg derivative in the CPS. The genes encoding the acetyltransferases were in different putative phage genomes. However, related acetyltransferases were rare among the >3000 publically available genome sequences.
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Affiliation(s)
- Johanna J. Kenyon
- Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
- * E-mail:
| | - Nikolay P. Arbatsky
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail M. Shneider
- M. M. Shemyakin & Y. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya V. Popova
- Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, Russia
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Moscow Region, Russia
| | - Andrei S. Dmitrenok
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya A. Kasimova
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Higher Chemical College of the Russian Academy of Sciences, D. I. Mendeleev University of Chemical Technology of Russia, Moscow, Russia
| | - Alexander S. Shashkov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Ruth M. Hall
- School of Life and Environmental Sciences, The University of Sydney, Sydney, Australia
| | - Yuriy A. Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
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27
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Pereira SB, Santos M, Leite JP, Flores C, Eisfeld C, Büttel Z, Mota R, Rossi F, De Philippis R, Gales L, Morais‐Cabral JH, Tamagnini P. The role of the tyrosine kinase Wzc (Sll0923) and the phosphatase Wzb (Slr0328) in the production of extracellular polymeric substances (EPS) by Synechocystis PCC 6803. Microbiologyopen 2019; 8:e00753. [PMID: 30675753 PMCID: PMC6562117 DOI: 10.1002/mbo3.753] [Citation(s) in RCA: 14] [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: 06/06/2018] [Revised: 09/21/2018] [Accepted: 09/22/2018] [Indexed: 11/10/2022] Open
Abstract
Many cyanobacteria produce extracellular polymeric substances (EPS) mainly composed of heteropolysaccharides with unique characteristics that make them suitable for biotechnological applications. However, manipulation/optimization of EPS biosynthesis/characteristics is hindered by a poor understanding of the production pathways and the differences between bacterial species. In this work, genes putatively related to different pathways of cyanobacterial EPS polymerization, assembly, and export were targeted for deletion or truncation in the unicellular Synechocystis sp. PCC 6803. No evident phenotypic changes were observed for some mutants in genes occurring in multiple copies in Synechocystis genome, namely ∆wzy (∆sll0737), ∆wzx (∆sll5049), ∆kpsM (∆slr2107), and ∆kpsM∆wzy (∆slr2107∆sll0737), strongly suggesting functional redundancy. In contrast, Δwzc (Δsll0923) and Δwzb (Δslr0328) influenced both the amount and composition of the EPS, establishing that Wzc participates in the production of capsular (CPS) and released (RPS) polysaccharides, and Wzb affects RPS production. The structure of Wzb was solved (2.28 Å), revealing structural differences relative to other phosphatases involved in EPS production and suggesting a different substrate recognition mechanism. In addition, Wzc showed the ATPase and autokinase activities typical of bacterial tyrosine kinases. Most importantly, Wzb was able to dephosphorylate Wzc in vitro, suggesting that tyrosine phosphorylation/dephosphorylation plays a role in cyanobacterial EPS production.
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Affiliation(s)
- Sara B. Pereira
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
| | - Marina Santos
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- ICBAS – Instituto de Ciências Biomédicas Abel SalazarPortoPortugal
| | - José P. Leite
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- ICBAS – Instituto de Ciências Biomédicas Abel SalazarPortoPortugal
| | - Carlos Flores
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- ICBAS – Instituto de Ciências Biomédicas Abel SalazarPortoPortugal
| | - Carina Eisfeld
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- Present address:
Department of Water ManagementDelft University of TechnologyDelftThe Netherlands
| | - Zsófia Büttel
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- Present address:
Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology InstituteUniversity of GroningenGroningenThe Netherlands
| | - Rita Mota
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
| | - Federico Rossi
- Department of Agrifood Production and Environmental SciencesUniversity of FlorenceFlorenceItaly
| | - Roberto De Philippis
- Department of Agrifood Production and Environmental SciencesUniversity of FlorenceFlorenceItaly
| | - Luís Gales
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- ICBAS – Instituto de Ciências Biomédicas Abel SalazarPortoPortugal
| | - João H. Morais‐Cabral
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
| | - Paula Tamagnini
- i3S ‐ Instituto de Investigação e Inovação em SaúdeUniversidade do PortoPortoPortugal
- IBMC ‐ Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- Faculdade de Ciências, Departamento de BiologiaUniversidade do PortoPortoPortugal
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Pan Y, Lin T, Chen Y, Lai P, Tsai Y, Hsu C, Hsieh P, Lin Y, Wang J. Identification of three podoviruses infecting Klebsiella encoding capsule depolymerases that digest specific capsular types. Microb Biotechnol 2019; 12:472-486. [PMID: 30706654 PMCID: PMC6465236 DOI: 10.1111/1751-7915.13370] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [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: 07/27/2018] [Revised: 12/13/2018] [Accepted: 12/21/2018] [Indexed: 12/11/2022] Open
Abstract
Klebsiella pneumoniae is an important human pathogen causing opportunistic nosocomial and community-acquired infections. A major public health concern regarding K. pneumoniae is the increasing incidence of multidrug-resistant strains. Here, we isolated three novel Klebsiella bacteriophages, KN1-1, KN3-1 and KN4-1, which infect KN1, KN3 and K56, and KN4 types respectively. We determined their genome sequences and conducted a comparative analysis that revealed a variable region containing capsule depolymerase-encoding genes. Recombinant depolymerase proteins were produced, and their enzymatic activity and specificity were evaluated. We identified four capsule depolymerases in these phages that could only digest the capsule types of their respective hosts. Our results demonstrate that the activities of these capsule depolymerases were correlated with the host range of each phage; thus, the capsule depolymerases are host specificity determinants. By generating a capsule mutant, we demonstrate that capsule was essential for phage adsorption and infection. Further, capsule depolymerases can enhance bacterial susceptibility to serum killing. The discovery of these phages and depolymerases lays the foundation for the typing of KN1, KN3, KN4 and K56 Klebsiella and could be useful alternative therapeutics for the treatment of K. pneumoniae infections.
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Affiliation(s)
- Yi‐Jiun Pan
- Department of Microbiology and ImmunologySchool of MedicineChina Medical UniversityTaichungTaiwan
| | - Tzu‐Lung Lin
- Department of Medical Biotechnology and Laboratory scienceCollege of MedicineChang Gung UniversityTaoyuanTaiwan
| | - Yi‐Yin Chen
- Department of PediatricsCollege of MedicineChang Gung Children's HospitalChang Gung Memorial HospitalChang Gung UniversityTaoyuanTaiwan
| | - Peng‐Hsuan Lai
- Department of Microbiology and ImmunologySchool of MedicineChina Medical UniversityTaichungTaiwan
| | - Yun‐Ting Tsai
- Department of Microbiology and ImmunologySchool of MedicineChina Medical UniversityTaichungTaiwan
| | - Chun‐Ru Hsu
- Department of Medical ResearchE‐Da HospitalKaohsiungTaiwan
| | - Pei‐Fang Hsieh
- Department of MicrobiologyNational Taiwan University College of MedicineTaipeiTaiwan
| | - Yi‐Tsung Lin
- Division of Infectious DiseasesDepartment of MedicineTaipei Veterans General HospitalTaipeiTaiwan
| | - Jin‐Town Wang
- Department of MicrobiologyNational Taiwan University College of MedicineTaipeiTaiwan
- Department of Internal MedicineNational Taiwan University HospitalTaipeiTaiwan
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Wyres KL, Wick RR, Judd LM, Froumine R, Tokolyi A, Gorrie CL, Lam MMC, Duchêne S, Jenney A, Holt KE. Distinct evolutionary dynamics of horizontal gene transfer in drug resistant and virulent clones of Klebsiella pneumoniae. PLoS Genet 2019; 15:e1008114. [PMID: 30986243 PMCID: PMC6483277 DOI: 10.1371/journal.pgen.1008114] [Citation(s) in RCA: 171] [Impact Index Per Article: 34.2] [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: 11/08/2018] [Revised: 04/25/2019] [Accepted: 03/29/2019] [Indexed: 11/19/2022] Open
Abstract
Klebsiella pneumoniae has emerged as an important cause of two distinct public health threats: multi-drug resistant (MDR) healthcare-associated infections and drug susceptible community-acquired invasive infections. These pathotypes are generally associated with two distinct subsets of K. pneumoniae lineages or 'clones' that are distinguished by the presence of acquired resistance genes and several key virulence loci. Genomic evolutionary analyses of the most notorious MDR and invasive community-associated ('hypervirulent') clones indicate differences in terms of chromosomal recombination dynamics and capsule polysaccharide diversity, but it remains unclear if these differences represent generalised trends. Here we leverage a collection of >2200 K. pneumoniae genomes to identify 28 common clones (n ≥ 10 genomes each), and perform the first genomic evolutionary comparison. Eight MDR and 6 hypervirulent clones were identified on the basis of acquired resistance and virulence gene prevalence. Chromosomal recombination, surface polysaccharide locus diversity, pan-genome, plasmid and phage dynamics were characterised and compared. The data showed that MDR clones were highly diverse, with frequent chromosomal recombination generating extensive surface polysaccharide locus diversity. Additional pan-genome diversity was driven by frequent acquisition/loss of both plasmids and phage. In contrast, chromosomal recombination was rare in the hypervirulent clones, which also showed a significant reduction in pan-genome diversity, largely driven by a reduction in plasmid diversity. Hence the data indicate that hypervirulent clones may be subject to some sort of constraint for horizontal gene transfer that does not apply to the MDR clones. Our findings are relevant for understanding the risk of emergence of individual K. pneumoniae strains carrying both virulence and acquired resistance genes, which have been increasingly reported and cause highly virulent infections that are extremely difficult to treat. Specifically, our data indicate that MDR clones pose the greatest risk, because they are more likely to acquire virulence genes than hypervirulent clones are to acquire resistance genes.
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Affiliation(s)
- Kelly L. Wyres
- Department of Infectious Diseases, Monash University, Melbourne, Victoria, Australia
| | - Ryan R. Wick
- Department of Infectious Diseases, Monash University, Melbourne, Victoria, Australia
| | - Louise M. Judd
- Department of Infectious Diseases, Monash University, Melbourne, Victoria, Australia
| | - Roni Froumine
- Department of Infectious Diseases, Monash University, Melbourne, Victoria, Australia
| | - Alex Tokolyi
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Claire L. Gorrie
- Department of Infectious Diseases and Microbiology Unit, The Alfred Hospital, Melbourne, Victoria, Australia
| | - Margaret M. C. Lam
- Department of Infectious Diseases, Monash University, Melbourne, Victoria, Australia
| | - Sebastián Duchêne
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Adam Jenney
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Kathryn E. Holt
- Department of Infectious Diseases, Monash University, Melbourne, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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Lee H, Shin J, Chung YJ, Baek JY, Chung DR, Peck KR, Song JH, Ko KS. Evolution of Klebsiella pneumoniae with mucoid and non-mucoid type colonies within a single patient. Int J Med Microbiol 2019; 309:194-198. [PMID: 30885571 DOI: 10.1016/j.ijmm.2019.03.003] [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: 08/22/2018] [Revised: 02/20/2019] [Accepted: 03/04/2019] [Indexed: 12/17/2022] Open
Abstract
We obtained nine Klebsiella pneumoniae isolates successively isolated from a single patient. Four pairs (M1-M4 and NM1-NM4) obtained simultaneously from the same site showed different colony types, mucoid and non-mucoid, while the final isolate (M5) was isolated alone from the blood and showed a mucoid phenotype. The whole genome of isolate M5 was sequenced de novo using the PacBio RSII system, while the others were sequenced with an Illumina Hiseq4000 and mapped to the genome sequences of M5. To identify insertions or deletions in the cps locus, we amplified and sequenced cps locus genes. We identified insertion sequence (IS) elements in several genes of the cps locus or one amino acid substitution in WcaJ in all non-mucoid isolates. Five additional amino acid alterations in RpsJ, LolE, Lon-2, PpsE, and a hypothetical protein were detected in some mucoid and non-mucoid isolates. Based on the genome data and cps locus sequences, the mucoid phenotype may have been lost or converted into the non-mucoid phenotype because of the insertion of IS elements or amino acid alterations at this locus. We inferred a within-host evolutionary scenario, in which non-mucoid variants emerged repeatedly from mucoid isolates, but may be short-lived because of their low fitness.
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Affiliation(s)
- Haejeong Lee
- Department of Molecular Cell Biology and Samsung Medical Center, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Juyoun Shin
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Yeun-Jun Chung
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea; Precision Medicine Research Center, Integrated Research Center for Genome Polymorphism, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Jin Yang Baek
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea
| | - Doo Ryeon Chung
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea; Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
| | - Kyong Ran Peck
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
| | - Jae-Hoon Song
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea
| | - Kwan Soo Ko
- Department of Molecular Cell Biology and Samsung Medical Center, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea; Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea.
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Zhang D, Ke X, Liu Z, Cao J, Su Y, Lu M, Gao F, Wang M, Yi M, Qin F. Capsular polysaccharide of Streptococcus agalactiae is an essential virulence factor for infection in Nile tilapia (Oreochromis niloticus Linn.). J Fish Dis 2019; 42:293-302. [PMID: 30549284 DOI: 10.1111/jfd.12935] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/13/2018] [Accepted: 11/13/2018] [Indexed: 06/09/2023]
Abstract
Streptococcus agalactiae (Group B Streptococcus, GBS) is associated with diverse diseases in aquatic animals. The capsule polysaccharide (CPS) encoded by the cps gene cluster is the major virulence factor of S. agalactiae; however, limited information is available regarding the pathogenic role of the CPS of serotype Ia piscine GBS strains in fish. Here, a non-encapsulated mutant (Δcps) was constructed by insertional mutagenesis of the cps gene cluster. Mutant pathogenicity was evaluated in vitro based on the killing of whole blood from tilapia, in vivo infections, measuring mutant survival in tilapia spleen tissues and pathological analysis. Compared to wild-type (WT) GBS strain, the Δcps mutant had lower resistance to fresh tilapia whole blood in vitro (p < 0.01), and more easily cleared in tilapia spleen tissue, and was highly attenuated in tilapia and zebrafish. Additionally, compared to the Δcps mutant, numerous GBS strains and severe tissue necrosis were observed in the tilapia spleen tissue infected with WT strains. These results indicated that the CPS is essential for GBS pathogenicity and may serve as a target for attenuation in vaccine development. Gaining a better understanding of the role, the GBS pathogenicity in fish will provide insight into related pathogenesis and host-pathogen interactions.
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Affiliation(s)
- Defeng Zhang
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Xiaoli Ke
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Zhigang Liu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Jianmeng Cao
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Youlu Su
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Maixin Lu
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Fengying Gao
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Miao Wang
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Mengmeng Yi
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Fengling Qin
- Core Facility for Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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Mohamed N, Timofeyeva Y, Jamrozy D, Rojas E, Hao L, Silmon de Monerri NC, Hawkins J, Singh G, Cai B, Liberator P, Sebastian S, Donald RGK, Scully IL, Jones CH, Creech CB, Thomsen I, Parkhill J, Peacock SJ, Jansen KU, Holden MTG, Anderson AS. Molecular epidemiology and expression of capsular polysaccharides in Staphylococcus aureus clinical isolates in the United States. PLoS One 2019; 14:e0208356. [PMID: 30641545 PMCID: PMC6331205 DOI: 10.1371/journal.pone.0208356] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [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: 08/25/2018] [Accepted: 11/15/2018] [Indexed: 12/14/2022] Open
Abstract
Staphylococcus aureus capsular polysaccharides (CP) are important virulence factors under evaluation as vaccine antigens. Clinical S. aureus isolates have the biosynthetic capability to express either CP5 or CP8 and an understanding of the relationship between CP genotype/phenotype and S. aureus epidemiology is valuable. Using whole genome sequencing, the clonal relatedness and CP genotype were evaluated for disease-associated S. aureus isolates selected from the Tigecycline Evaluation and Surveillance Trial (T.E.S.T) to represent different geographic regions in the United States (US) during 2004 and 2009–10. Thirteen prominent clonal complexes (CC) were identified, with CC5, 8, 30 and 45 representing >80% of disease isolates. CC5 and CC8 isolates were CP type 5 and, CC30 and CC45 isolates were CP type 8. Representative isolates from prevalent CC were susceptible to in vitro opsonophagocytic killing elicited by anti-CP antibodies, demonstrating that susceptibility to opsonic killing is not linked to the genetic lineage. However, as not all S. aureus isolates may express CP, isolates representing the diversity of disease isolates were assessed for CP production. While approximately 35% of isolates (primarily CC8) did not express CP in vitro, CP expression could be clearly demonstrated in vivo for 77% of a subset of these isolates (n = 20) despite the presence of mutations within the capsule operon. CP expression in vivo was also confirmed indirectly by measuring an increase in CP specific antibodies in mice infected with CP5 or CP8 isolates. Detection of antigen expression in vivo in relevant disease states is important to support the inclusion of these antigens in vaccines. Our findings confirm the validity of CP as vaccine targets and the potential of CP-based vaccines to contribute to S. aureus disease prevention.
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Affiliation(s)
- Naglaa Mohamed
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Yekaterina Timofeyeva
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Dorota Jamrozy
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Eduardo Rojas
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Li Hao
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | | | - Julio Hawkins
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Guy Singh
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Bing Cai
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Paul Liberator
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Shite Sebastian
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Robert G. K. Donald
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Ingrid L. Scully
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - C. Hal Jones
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - C. Buddy Creech
- Vanderbilt Vaccine Research Program, Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Isaac Thomsen
- Vanderbilt Vaccine Research Program, Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Julian Parkhill
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Sharon J. Peacock
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kathrin U. Jansen
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | | | - Annaliesa S. Anderson
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
- * E-mail:
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Sham LT, Zheng S, Yakhnina AA, Kruse AC, Bernhardt TG. Loss of specificity variants of WzxC suggest that substrate recognition is coupled with transporter opening in MOP-family flippases. Mol Microbiol 2018; 109:633-641. [PMID: 29907971 PMCID: PMC6181778 DOI: 10.1111/mmi.14002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [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] [Accepted: 07/15/2018] [Indexed: 12/26/2022]
Abstract
Bacteria produce a variety of surface-exposed polysaccharides important for cell integrity, biofilm formation and evasion of the host immune response. Synthesis of these polymers often involves the assembly of monomer oligosaccharide units on the lipid carrier undecaprenyl-phosphate at the inner face of the cytoplasmic membrane. For many polymers, including cell wall peptidoglycan, the lipid-linked precursors must be transported across the membrane by flippases to facilitate polymerization at the membrane surface. Flippase activity for this class of polysaccharides is most often attributed to MOP (Multidrug/Oligosaccharidyl-lipid/Polysaccharide) family proteins. Little is known about how this ubiquitous class of transporters identifies and translocates its cognate precursor over the many different types of lipid-linked oligosaccharides produced by a given bacterial cell. To investigate the specificity determinants of MOP proteins, we selected for variants of the WzxC flippase involved in Escherichia coli capsule (colanic acid) synthesis that can substitute for the essential MurJ MOP-family protein and promote transport of cell wall peptidoglycan precursors. Variants with substitutions predicted to destabilize the inward-open conformation of WzxC lost substrate specificity and supported both capsule and peptidoglycan synthesis. Our results thus suggest that specific substrate recognition by a MOP transporter normally destabilizes the inward-open state, promoting transition to the outward-open conformation and concomitant substrate translocation. Furthermore, the ability of WzxC variants to suppress MurJ inactivation provides strong support for the designation of MurJ as the flippase for peptidoglycan precursors, the identity of which has been controversial.
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Affiliation(s)
- Lok To Sham
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
- Department of Microbiology and Immunology, National University of Singapore, Singapore, 117545
| | - Sanduo Zheng
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | | | - Andrew C. Kruse
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | - Thomas G. Bernhardt
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
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Scarff JM, Seldina YI, Vergis JM, Ventura CL, O’Brien AD. Expression and contribution to virulence of each polysaccharide capsule of Bacillus cereus strain G9241. PLoS One 2018; 13:e0202701. [PMID: 30133532 PMCID: PMC6105005 DOI: 10.1371/journal.pone.0202701] [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: 04/13/2018] [Accepted: 08/06/2018] [Indexed: 12/03/2022] Open
Abstract
Bacillus cereus strain G9241 was isolated from a patient with pneumonia who had an anthrax-like illness. Like Bacillus anthracis, the virulence of G9241 is dependent on two large plasmids. In G9241 those plasmids are pBCXO1 and pBC210. There is a multi-gene capsule locus on each of these virulence plasmids, and both capsules are produced by G9241 in vitro and in mice. The hasACB operon on pBCXO1 is responsible for production of a hyaluronic acid (HA) capsule. The locus on pBC210 encodes a putative tetrasaccharide (TS) capsule that assembles in a Wzy-dependent manner. We found that the pBC210 capsule locus is transcribed as two operons and identified the promoter regions responsible for transcription. We constructed isogenic mutants to assess the role of genes in the two TS capsule operons in production of the capsule. Spores of strains deficient in production of either the HA or TS capsule were inoculated subcutaneously or intranasally into A/J and C57BL/6 mice to determine the lethal dose 50% of each bacterial mutant by each route of infection. The loss of the HA capsule attenuated G9241 more than the loss of the TS capsule for both infection routes in both mouse strains. Overall, our data further characterize the unique TS capsule on pBC210 and demonstrate that the two capsules do not have the same impact on virulence of G9241.
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Affiliation(s)
- Jennifer M. Scarff
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States of America
| | - Yuliya I. Seldina
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States of America
| | - James M. Vergis
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States of America
| | - Christy L. Ventura
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States of America
| | - Alison D. O’Brien
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States of America
- * E-mail:
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Jang H, Matthews KR. Survival and interaction of Escherichia coli O104:H4 on Arabidopsis thaliana and lettuce (Lactuca sativa) in comparison to E. coli O157:H7: Influence of plant defense response and bacterial capsular polysaccharide. Food Res Int 2018; 108:35-41. [PMID: 29735067 DOI: 10.1016/j.foodres.2018.03.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [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: 01/05/2018] [Revised: 03/07/2018] [Accepted: 03/09/2018] [Indexed: 10/17/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) has been associated with illnesses and outbreaks linked to fresh vegetables, prompting a growing public health concern. Most studies regarding interactions of STEC on fresh produce focused on E. coli O157:H7. Limited information is available about survival or fitness of E. coli O104:H4, non-O157 pathogen that was linked to one of the largest outbreaks of hemolytic uremic syndrome in 2011. In this study, survival of E. coli O104:H4 was evaluated on Arabidopsis thaliana plant and lettuce for 5 days compared with E. coli O157:H7, and expression of pathogenesis-realted gene (PR1; induction of plant defense response) was examined by reverse transcription quantitative PCR, and potential influence of capsular polysaccharide (CPS) on the bacterial fitness on plant was investigated. Populations of E. coli O104:H4 strains (RG1, C3493, and LpfA) on Arabidopsis and lettuce were significantly (P < 0.05) greater than those of E. coli O157:H7 strains (7386 and sakai) at day 5 post-inoculation, indicating E. coli O104:H4 may have better survival ability on the plants. In addition, the E. coli O104:H4 strains produced significantly (P < 0.05) higher amounts of CPS compared with the E. coli O157:H7 strains. RG1 strain (1.5-fold) initiated significantly (P < 0.05) lower expression of PR1 gene indicating induction of plant defense response compared with E. coli O157:H7 strains 7386 (2.9-fold) and sakai (2.7-fold). Collectively, the results in this study suggests that different level of CPS production and plant defense response initiated by each STEC strain might influence the bacterial survival or persistence on plants. The present study provides better understanding of survival behavior of STEC, particularly E. coli O104:H4, using a model plant and vegetable under pre-harvest conditions with plant defense response.
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Affiliation(s)
- Hyein Jang
- Department of Food Science, Rutgers University, New Brunswick, NJ 08901, USA
| | - Karl R Matthews
- Department of Food Science, Rutgers University, New Brunswick, NJ 08901, USA.
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Litschko C, Oldrini D, Budde I, Berger M, Meens J, Gerardy-Schahn R, Berti F, Schubert M, Fiebig T. A New Family of Capsule Polymerases Generates Teichoic Acid-Like Capsule Polymers in Gram-Negative Pathogens. mBio 2018; 9:e00641-18. [PMID: 29844111 PMCID: PMC5974469 DOI: 10.1128/mbio.00641-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [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: 03/21/2018] [Accepted: 05/02/2018] [Indexed: 02/07/2023] Open
Abstract
Group 2 capsule polymers represent crucial virulence factors of Gram-negative pathogenic bacteria. They are synthesized by enzymes called capsule polymerases. In this report, we describe a new family of polymerases that combine glycosyltransferase and hexose- and polyol-phosphate transferase activity to generate complex poly(oligosaccharide phosphate) and poly(glycosylpolyol phosphate) polymers, the latter of which display similarity to wall teichoic acid (WTA), a cell wall component of Gram-positive bacteria. Using modeling and multiple-sequence alignment, we showed homology between the predicted polymerase domains and WTA type I biosynthesis enzymes, creating a link between Gram-negative and Gram-positive cell wall biosynthesis processes. The polymerases of the new family are highly abundant and found in a variety of capsule-expressing pathogens such as Neisseria meningitidis, Actinobacillus pleuropneumoniae, Haemophilus influenzae, Bibersteinia trehalosi, and Escherichia coli with both human and animal hosts. Five representative candidates were purified, their activities were confirmed using nuclear magnetic resonance (NMR) spectroscopy, and their predicted folds were validated by site-directed mutagenesis.IMPORTANCE Bacterial capsules play an important role in the interaction between a pathogen and the immune system of its host. During the last decade, capsule polymerases have become attractive tools for the production of capsule polymers applied as antigens in glycoconjugate vaccine formulations. Conventional production of glycoconjugate vaccines requires the cultivation of the pathogen and thus the highest biosafety standards, leading to tremendous costs. With regard to animal husbandry, where vaccines could avoid the extensive use of antibiotics, conventional production is not sufficiently cost-effective. In contrast, enzymatic synthesis of capsule polymers is pathogen-free and fast, offers high stereo- and regioselectivity, and works with high efficacy. The new capsule polymerase family described here vastly increases the toolbox of enzymes available for biotechnology purposes. Representatives are abundantly found in human pathogens but also in animal pathogens, paving the way for the exploitation of polymerases for the development of a new generation of vaccines for animal husbandry.
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Affiliation(s)
- Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | | | - Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Monika Berger
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Jochen Meens
- Institute for Microbiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | | | - Mario Schubert
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
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Ghimire S, McCarthy PC. Capture of Pb 2+ and Cu 2+ Metal Cations by Neisseria meningitidis-type Capsular Polysaccharides. Biomolecules 2018; 8:E23. [PMID: 29734757 PMCID: PMC6023028 DOI: 10.3390/biom8020023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [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: 04/16/2018] [Revised: 05/02/2018] [Accepted: 05/02/2018] [Indexed: 12/14/2022] Open
Abstract
Heavy metal pollution of water is a significant environmental and public health concern. Current biological strategies for heavy metal removal from water are performed using microbial biopolymers, including polysaccharides, that are already fully formed. This creates limitations in adapting polysaccharides to increase binding affinity for specific metals. We propose that altering the specificity of polysaccharide-producing enzymes could be beneficial to improving metal capture by modified polysaccharides. We assess binding of Cu2+ and Pb2+ metal cations to Neisseria meningitidis-type polysaccharides. All concentrations of metal cations tested were able to completely bind to colominic acid. This polymer is equivalent to the capsular polysaccharide of N. meningitidis serogroup B comprised of a homopolymer of negatively charged sialic acid. There was slightly less binding observed with N. meningitidis serogroup W, which contains repeating units of the neutral sugar galactose and sialic acid. Our work represents the first assessment of the metal-binding properties of these capsular polysaccharides. Future work will seek to optimize metal-binding with Neisseria meningitidis serogroup W polysaccharide.
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Affiliation(s)
- Sujan Ghimire
- Department of Chemistry, Morgan State University, Baltimore, MD 21251, USA.
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Ispasanie E, Micoli F, Lamelas A, Keller D, Berti F, De Riccio R, Di Benedettoi R, Rondini S, Pluschke G. Spontaneous point mutations in the capsule synthesis locus leading to structural and functional changes of the capsule in serogroup A meningococcal populations. Virulence 2018; 9:1138-1149. [PMID: 30067453 PMCID: PMC6086313 DOI: 10.1080/21505594.2018.1467710] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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: 01/12/2018] [Accepted: 04/13/2018] [Indexed: 01/09/2023] Open
Abstract
Whole genome sequencing analysis of 100 Neisseria meningitidis serogroup A isolates has revealed that the csaABCD-ctrABCD-ctrEF capsule polysaccharide synthesis locus represents a spontaneous point mutation hotspot. Structural and functional properties of the capsule of 11 carriage and two disease isolates with non-synonymous point mutations or stop codons in capsule synthesis genes were analyzed for their capsular polysaccharide expression, recognition by antibodies and sensitivity to bactericidal killing. Eight of eleven carriage isolates presenting capsule locus mutations expressed no or reduced amounts of capsule. One isolate with a stop codon in the O-acetyltransferase gene expressed non-O-acetylated polysaccharide, and was not recognized by anti-capsule antibodies. Capsule and O-acetylation deficient mutants were resistant to complement deposition and killing mediated by anti-capsular antibodies, but not by anti-lipopolysaccharide antibodies. Two capsule polymerase mutants, one carriage and one case isolate, showed capsule over-expression and increased resistance against bactericidal activity of both capsule- and lipopolysaccharide-specific antibodies. Meningococci have developed multiple strategies for changing capsule expression and structure, which is relevant both for colonization and virulence. Here we show that point mutations in the capsule synthesis genes substantially contribute to the repertoire of genetic mechanisms in natural populations leading to variability in capsule expression.
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Affiliation(s)
- Emma Ispasanie
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Araceli Lamelas
- Red de Estudios Moleculares Avanzados, Instituto de Ecologia, A.C., Veracruz, México
| | - Dominique Keller
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | | | | | | | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
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Mostowy RJ, Croucher NJ, De Maio N, Chewapreecha C, Salter SJ, Turner P, Aanensen DM, Bentley SD, Didelot X, Fraser C. Pneumococcal Capsule Synthesis Locus cps as Evolutionary Hotspot with Potential to Generate Novel Serotypes by Recombination. Mol Biol Evol 2017; 34:2537-2554. [PMID: 28595308 PMCID: PMC5850285 DOI: 10.1093/molbev/msx173] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [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] [Indexed: 01/08/2023] Open
Abstract
Diversity of the polysaccharide capsule in Streptococcus pneumoniae-main surface antigen and the target of the currently used pneumococcal vaccines-constitutes a major obstacle in eliminating pneumococcal disease. Such diversity is genetically encoded by almost 100 variants of the capsule biosynthesis locus, cps. However, the evolutionary dynamics of the capsule remains not fully understood. Here, using genetic data from 4,519 bacterial isolates, we found cps to be an evolutionary hotspot with elevated substitution and recombination rates. These rates were a consequence of relaxed purifying selection and positive, diversifying selection acting at this locus, supporting the hypothesis that the capsule has an increased potential to generate novel diversity compared with the rest of the genome. Diversifying selection was particularly evident in the region of wzd/wze genes, which are known to regulate capsule expression and hence the bacterium's ability to cause disease. Using a novel, capsule-centered approach, we analyzed the evolutionary history of 12 major serogroups. Such analysis revealed their complex diversification scenarios, which were principally driven by recombination with other serogroups and other streptococci. Patterns of recombinational exchanges between serogroups could not be explained by serotype frequency alone, thus pointing to nonrandom associations between co-colonizing serotypes. Finally, we discovered a previously unobserved mosaic serotype 39X, which was confirmed to carry a viable and structurally novel capsule. Adding to previous discoveries of other mosaic capsules in densely sampled collections, these results emphasize the strong adaptive potential of the bacterium by its ability to generate novel antigenic diversity by recombination.
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Affiliation(s)
- Rafał J. Mostowy
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
| | - Nicholas J. Croucher
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
| | - Nicola De Maio
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Institute for Emerging Infections, Oxford Martin School, Oxford, United Kingdom
| | - Claire Chewapreecha
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
- Bioinformatics and Systems Biology Program, School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
| | - Susannah J. Salter
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Paul Turner
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | - David M. Aanensen
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
- Centre for Genomic Pathogen Surveillance, Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Stephen D. Bentley
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Xavier Didelot
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
| | - Christophe Fraser
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
- Nuffield Department of Medicine, Li Ka Shing Centre for Health Information and Discovery, Oxford Big Data Institute, University of Oxford, Oxford, United Kingdom
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Taylor ZW, Brown HA, Narindoshvili T, Wenzel CQ, Szymanski CM, Holden HM, Raushel FM. Discovery of a Glutamine Kinase Required for the Biosynthesis of the O-Methyl Phosphoramidate Modifications Found in the Capsular Polysaccharides of Campylobacter jejuni. J Am Chem Soc 2017; 139:9463-9466. [PMID: 28650156 PMCID: PMC5629633 DOI: 10.1021/jacs.7b04824] [Citation(s) in RCA: 21] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bacterial capsular polysaccharides (CPS) are complex carbohydrate structures that play a role in the overall fitness of the organism. Campylobacter jejuni, known for being a major cause of bacterial gastroenteritis worldwide, produces a CPS with a unique O-methyl phosphoramidate (MeOPN) modification on specific sugar residues. The formation of P-N bonds in nature is relatively rare, and the pathway for the assembly of the phosphoramidate moiety in the CPS of C. jejuni is unknown. In this investigation we discovered that the initial transformation in the biosynthetic pathway for the MeOPN modification of the CPS involves the direct phosphorylation of the amide nitrogen of l-glutamine with ATP by the catalytic activity of Cj1418. The other two products are AMP and inorganic phosphate. The l-glutamine-phosphate product was characterized using 31P NMR spectroscopy and mass spectrometry. We suggest that this newly discovered enzyme be named l-glutamine kinase.
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Affiliation(s)
- Zane W. Taylor
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, 77843
| | - Haley A. Brown
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | | | - Cory Q. Wenzel
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - Christine M. Szymanski
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
- Department of Microbiology and Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, 30602
| | - Hazel M. Holden
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Frank M. Raushel
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, 77843
- Department of Chemistry, Texas A&M University, College Station, Texas, 77843
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Majkowska-Skrobek G, Łątka A, Berisio R, Maciejewska B, Squeglia F, Romano M, Lavigne R, Struve C, Drulis-Kawa Z. Capsule-Targeting Depolymerase, Derived from Klebsiella KP36 Phage, as a Tool for the Development of Anti-Virulent Strategy. Viruses 2016; 8:v8120324. [PMID: 27916936 PMCID: PMC5192385 DOI: 10.3390/v8120324] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [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: 09/22/2016] [Revised: 11/17/2016] [Accepted: 11/23/2016] [Indexed: 01/13/2023] Open
Abstract
The rise of antibiotic-resistant Klebsiella pneumoniae, a leading nosocomial pathogen, prompts the need for alternative therapies. We have identified and characterized a novel depolymerase enzyme encoded by Klebsiella phage KP36 (depoKP36), from the Siphoviridae family. To gain insights into the catalytic and structural features of depoKP36, we have recombinantly produced this protein of 93.4 kDa and showed that it is able to hydrolyze a crude exopolysaccharide of a K. pneumoniae host. Using in vitro and in vivo assays, we found that depoKP36 was also effective against a native capsule of clinical K. pneumoniae strains, representing the K63 type, and significantly inhibited Klebsiella-induced mortality of Galleria mellonella larvae in a time-dependent manner. DepoKP36 did not affect the antibiotic susceptibility of Klebsiella strains. The activity of this enzyme was retained in a broad range of pH values (4.0–7.0) and temperatures (up to 45 °C). Consistently, the circular dichroism (CD) spectroscopy revealed a highly stability with melting transition temperature (Tm) = 65 °C. In contrast to other phage tailspike proteins, this enzyme was susceptible to sodium dodecyl sulfate (SDS) denaturation and proteolytic cleavage. The structural studies in solution showed a trimeric arrangement with a high β-sheet content. Our findings identify depoKP36 as a suitable candidate for the development of new treatments for K. pneumoniae infections.
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Affiliation(s)
- Grażyna Majkowska-Skrobek
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
| | - Agnieszka Łątka
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
| | - Rita Berisio
- Institute of Biostructures and Bioimaging, National Research Council, Via Mezzocannone 16, I-80134 Naples, Italy.
| | - Barbara Maciejewska
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
| | - Flavia Squeglia
- Institute of Biostructures and Bioimaging, National Research Council, Via Mezzocannone 16, I-80134 Naples, Italy.
| | - Maria Romano
- Institute of Biostructures and Bioimaging, National Research Council, Via Mezzocannone 16, I-80134 Naples, Italy.
| | - Rob Lavigne
- Laboratory of Gene Technology, KU Leuven, Kasteelpark Arenberg 21, box 2462, B-3001 Leuven, Belgium.
| | - Carsten Struve
- Department of Microbiology and Infection Control, Statens Serum Institut, Artillerivej 5, DK-2300S Copenhagen, Denmark.
- World Health Organization Collaborating Centre for Reference and Research on Escherichia and Klebsiella, Statens Serum Institut, Artillerivej 5, DK-2300S Copenhagen, Denmark.
| | - Zuzanna Drulis-Kawa
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
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Echlin H, Frank MW, Iverson A, Chang TC, Johnson MDL, Rock CO, Rosch JW. Pyruvate Oxidase as a Critical Link between Metabolism and Capsule Biosynthesis in Streptococcus pneumoniae. PLoS Pathog 2016; 12:e1005951. [PMID: 27760231 PMCID: PMC5070856 DOI: 10.1371/journal.ppat.1005951] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [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: 04/17/2016] [Accepted: 09/23/2016] [Indexed: 01/12/2023] Open
Abstract
The pneumococcus is one of the most prodigious producers of hydrogen peroxide amongst bacterial pathogens. Hydrogen peroxide production by the pneumococcus has been implicated in antibiotic synergism, competition between other bacterial colonizers of the nasopharynx, and damage to epithelial cells. However, the role during invasive disease has been less clear with mutants defective in hydrogen peroxide production demonstrating both attenuation and heightened invasive disease capacity depending upon strain and serotype background. This work resolves these conflicting observations by demonstrating that the main hydrogen peroxide producing enzyme of the pneumococcus, SpxB, is required for capsule formation in a strain dependent manner. Capsule production by strains harboring capsules with acetylated sugars was dependent upon the presence of spxB while capsule production in serotypes lacking such linkages were not. The spxB mutant had significantly lower steady-state cellular levels of acetyl-CoA, suggesting that loss of capsule arises from dysregulation of this intermediary metabolite. This conclusion is corroborated by deletion of pdhC, which also resulted in lower steady-state acetyl-CoA levels and phenocopied the capsule expression profile of the spxB mutant. Capsule and acetyl-CoA levels were restored in the spxB and lctO (lactate oxidase) double mutant, supporting the connection between central metabolism and capsule formation. Taken together, these data show that the defect in pathogenesis in the spxB mutant is due to a metabolic imbalance that attenuates capsule formation and not to reduced hydrogen peroxide formation. The pneumococcus polysaccharide capsule is one of the most critical virulence determinants produced by this major human pathogen. The pneumococcus also produces prodigious amounts of hydrogen peroxide via the enzymatic reaction catalyzed by pyruvate oxidase, SpxB. Deletion of spxB resulted in the loss of surface polysaccharide capsule production in a serotype dependent manner with a mirrored effect on the virulence of the mutants. We observed that deletion of spxB reduced the steady-state levels of acetyl-CoA, a key metabolic intermediate in peptidoglycan, fatty acid biosynthesis, and in capsule biosynthesis in a subset of serotypes. These data suggest that the defect in capsule production was due to altered metabolism that results in reduced acetyl-CoA availability. Corroborating these data, we found that capsule biosynthesis was impaired upon loss of PDHC, an additional metabolic enzyme that generates acetyl-CoA. These data reveal a critical link between pneumococcal metabolism and capsule biosynthesis as well as provide a striking example of how a virulence gene can have a differential contribution to pathogenesis dependent upon strain background.
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Affiliation(s)
- Haley Echlin
- Department of Infectious Diseases, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Matthew W. Frank
- Department of Infectious Diseases, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Amy Iverson
- Department of Infectious Diseases, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Ti-Cheng Chang
- Department of Computational Biology, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Michael D. L. Johnson
- Department of Infectious Diseases, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Charles O. Rock
- Department of Infectious Diseases, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Jason W. Rosch
- Department of Infectious Diseases, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- * E-mail:
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Abstract
Neisseria meningitidis, a devastating pathogen exclusive to humans, expresses capsular polysaccharides that are the major meningococcal virulence determinants and the basis for successful meningococcal vaccines. With rare exceptions, the expression of capsule (serogroups A, B, C, W, X, Y) is required for systemic invasive meningococcal disease. Changes in capsule expression or structure (e.g. hypo- or hyper-encapsulation, capsule "switching", acetylation) can influence immunologic diagnostic assays or lead to immune escape. The loss or down-regulation of capsule is also critical in meningococcal biology facilitating meningococcal attachment, microcolony formation and the carriage state at human mucosal surfaces. Encapsulated meningococci contain a cps locus with promoters located in an intergenic region between the biosynthesis and the conserved capsule transport operons. The cps intergenic region is transcriptionally regulated (and thus the amount of capsule expressed) by IS element insertion, by a two-component system, MisR/MisS and through sequence changes that result in post-transcriptional RNA thermoregulation. Reversible on-off phase variation of capsule expression is controlled by slipped strand mispairing of homo-polymeric tracts and by precise insertion and excision of IS elements (e.g. IS1301) in the biosynthesis operon. Capsule structure can be altered by phase-variable expression of capsular polymer modification enzymes or "switched" through transformation and homologous recombination of different polymerases. Understanding the complex regulation of meningococcal capsule has important implications for meningococcal biology, pathogenesis, diagnostics, current and future vaccine development and vaccine strategies.
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Affiliation(s)
- Yih-Ling Tzeng
- a Department of Medicine , Emory University School of Medicine, Woodruff Health Sciences Center , Atlanta , GA , USA
| | - Jennifer Thomas
- a Department of Medicine , Emory University School of Medicine, Woodruff Health Sciences Center , Atlanta , GA , USA
| | - David S Stephens
- a Department of Medicine , Emory University School of Medicine, Woodruff Health Sciences Center , Atlanta , GA , USA
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Mirza S, Benjamin WH, Coan PA, Hwang SA, Winslett AK, Yother J, Hollingshead SK, Fujihashi K, Briles DE. The effects of differences in pspA alleles and capsular types on the resistance of Streptococcus pneumoniae to killing by apolactoferrin. Microb Pathog 2016; 99:209-219. [PMID: 27569531 DOI: 10.1016/j.micpath.2016.08.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 08/15/2016] [Accepted: 08/23/2016] [Indexed: 11/18/2022]
Abstract
Pneumococcal surface protein A (PspA) is the only pneumococcal surface protein known to strongly bind lactoferrin on the bacterial surface. In the absence of PspA Streptococcus pneumoniae becomes more susceptible to killing by human apolactoferrin (apo-hLf), the iron-free form of lactoferrin. In the present study we examined diverse strains of S. pneumoniae that differed by 2 logs in their susceptibility to apo-hLf. Among these strains, the amount of apo-hLf that bound to cell surface PspA correlated directly with the resistance of the strain to killing by apo-hLf. Moreover examination of different pspA alleles on shared genetic backgrounds revealed that those PspAs that bound more lactoferrin conferred greater resistance to killing by apo-hLf. The effects of capsule on killing of pneumococci by apo-hLf were generally small, but on one genetic background, however, the lack of capsule was associated with 4-times as much apo-hLf binding and 30-times more resistance to killing by apo-hLf. Overall these finding strongly support the hypothesis that most of the variation in the ability of apo-hLf is dependent on the variation in the binding of apo-hLf to surface PspA and this binding is dependent on variation in PspA as well as variation in capsule which may enhance killing by reducing the binding of apo-hLf to PspA.
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Affiliation(s)
- Shaper Mirza
- Department of Biology, Lahore University of Management Sciences, Pakistan; Division of Epidemiology, Human Genetics and Environmental Health, School of Public Health, University of Texas, Health Science Center, Brownsville Regional Campus, TX, USA.
| | - William H Benjamin
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA; Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Patricia A Coan
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Shen-An Hwang
- Department of Pathology and Laboratory Medicine, Medical School University of Texas Health Science Center, Houston, TX, USA
| | - Anne-Kathryn Winslett
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Janet Yother
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Susan K Hollingshead
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Kohtaro Fujihashi
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA; Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA; Department of Pediatrics Dentistry, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - David E Briles
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA; Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
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Koliwer-Brandl H, Syson K, van de Weerd R, Chandra G, Appelmelk B, Alber M, Ioerger TR, Jacobs WR, Geurtsen J, Bornemann S, Kalscheuer R. Metabolic Network for the Biosynthesis of Intra- and Extracellular α-Glucans Required for Virulence of Mycobacterium tuberculosis. PLoS Pathog 2016; 12:e1005768. [PMID: 27513637 PMCID: PMC4981310 DOI: 10.1371/journal.ppat.1005768] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [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: 03/08/2016] [Accepted: 06/24/2016] [Indexed: 12/11/2022] Open
Abstract
Mycobacterium tuberculosis synthesizes intra- and extracellular α-glucans that were believed to originate from separate pathways. The extracellular glucose polymer is the main constituent of the mycobacterial capsule that is thought to be involved in immune evasion and virulence. However, the role of the α-glucan capsule in pathogenesis has remained enigmatic due to an incomplete understanding of α-glucan biosynthetic pathways preventing the generation of capsule-deficient mutants. Three separate and potentially redundant pathways had been implicated in α-glucan biosynthesis in mycobacteria: the GlgC-GlgA, the Rv3032 and the TreS-Pep2-GlgE pathways. We now show that α-glucan in mycobacteria is exclusively assembled intracellularly utilizing the building block α-maltose-1-phosphate as the substrate for the maltosyltransferase GlgE, with subsequent branching of the polymer by the branching enzyme GlgB. Some α-glucan is exported to form the α-glucan capsule. There is an unexpected convergence of the TreS-Pep2 and GlgC-GlgA pathways that both generate α-maltose-1-phosphate. While the TreS-Pep2 route from trehalose was already known, we have now established that GlgA forms this phosphosugar from ADP-glucose and glucose 1-phosphate 1000-fold more efficiently than its hitherto described glycogen synthase activity. The two routes are connected by the common precursor ADP-glucose, allowing compensatory flux from one route to the other. Having elucidated this unexpected configuration of the metabolic pathways underlying α-glucan biosynthesis in mycobacteria, an M. tuberculosis double mutant devoid of α-glucan could be constructed, showing a direct link between the GlgE pathway, α-glucan biosynthesis and virulence in a mouse infection model. Capsule formation is critical for the virulence of many bacterial and fungal pathogens. Mycobacterium tuberculosis cells are known to be surrounded by a capsule layer that is mainly composed of an α-glucan glucose polymer that resembles glycogen. Progress in understanding its role in the virulence of this important human pathogen has been held back by a lack of knowledge of its biosynthesis, preventing the generation of α-glucan-deficient mutants that could be tested in animal infection models. In this work, we unraveled an unexpected metabolic network configuration revealing the exclusive production of both intracellular and capsular α-glucans by the maltosyltransferase GlgE in mycobacteria. GlgE polymerizes an α-maltose 1-phosphate building block, which is generated by two alternative pathways that are connected by a common intermediate allowing rechanneling of flux from one route to the other. Elucidation of this unexpected configuration of the metabolic pathways underlying α-glucan biosynthesis allowed the rational construction of an M. tuberculosis mutant strain devoid of α-glucan, showing a direct link between the GlgE pathway, α-glucan biosynthesis and virulence in a mouse infection model.
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Affiliation(s)
- Hendrik Koliwer-Brandl
- Institute for Medical Microbiology and Hospital Hygiene, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Karl Syson
- Department of Biological Chemistry, John Innes Centre, Norwich, United Kingdom
| | - Robert van de Weerd
- Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands
| | - Govind Chandra
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Ben Appelmelk
- Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands
| | - Marina Alber
- Institute for Medical Microbiology and Hospital Hygiene, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Thomas R. Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, Texas, United States of America
| | - William R. Jacobs
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Jeroen Geurtsen
- Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands
| | - Stephen Bornemann
- Department of Biological Chemistry, John Innes Centre, Norwich, United Kingdom
| | - Rainer Kalscheuer
- Institute for Medical Microbiology and Hospital Hygiene, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- Institute for Pharmaceutical Biology and Biotechnology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- * E-mail:
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Tohya M, Watanabe T, Maruyama F, Arai S, Ota A, Athey TBT, Fittipaldi N, Nakagawa I, Sekizaki T. Comparative Genome Analyses of Streptococcus suis Isolates from Endocarditis Demonstrate Persistence of Dual Phenotypic Clones. PLoS One 2016; 11:e0159558. [PMID: 27433935 PMCID: PMC4951133 DOI: 10.1371/journal.pone.0159558] [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: 03/15/2016] [Accepted: 07/04/2016] [Indexed: 11/19/2022] Open
Abstract
Many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. In the present study, encapsulation in isolates of the porcine pathogen Streptococcus suis from persistent endocarditis lesions was examined. Coexistence of both encapsulated and unencapsulated S. suis isolates was found in 26 out of 59 endocarditis samples. The isolates were serotype 2, and belonged to two different sequence types (STs), ST1 and ST28. The genomes of each of the 26 pairs of encapsulated and unencapsulated isolates from the 26 samples were sequenced. The data showed that each pair of isolates had one or more unique nonsynonymous mutations in the cps gene, and the encapsulated and unencapsulated isolates from the same samples were closest to each other. Pairwise comparisons of the sequences of cps genes in 7 pairs of encapsulated and unencapsulated isolates identified insertion/deletions (indels) ranging from one to 104 bp in different cps genes of unencapsulated isolates. Capsule expression was restored in a subset of unencapsulated isolates by complementation in trans with cps expression vectors. Examination of gene content common to isolates indicated that mutation frequency was higher in ST28 pairs than in ST1 pairs. Genes within mobile genetic elements were mutation hot spots among ST28 isolates. Taken all together, our results demonstrate the coexistence of dual phenotype (encapsulated and unencapsulated) bacterial clones and suggest that the dual phenotypes arose independently in each farm by means of spontaneous mutations in cps genes.
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Affiliation(s)
- Mari Tohya
- Research Center for Food Safety, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Takayasu Watanabe
- Research Center for Food Safety, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Fumito Maruyama
- Department of Microbiology, Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan
- * E-mail: (TS); (FM)
| | - Sakura Arai
- Research Center for Food Safety, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Atsushi Ota
- Department of Microbiology, Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan
| | | | - Nahuel Fittipaldi
- Public Health Ontario, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Ichiro Nakagawa
- Department of Microbiology, Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan
| | - Tsutomu Sekizaki
- Research Center for Food Safety, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- * E-mail: (TS); (FM)
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Thamadilok S, Roche-Håkansson H, Håkansson AP, Ruhl S. Absence of capsule reveals glycan-mediated binding and recognition of salivary mucin MUC7 by Streptococcus pneumoniae. Mol Oral Microbiol 2016; 31:175-88. [PMID: 26172471 PMCID: PMC4713356 DOI: 10.1111/omi.12113] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [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] [Accepted: 06/28/2015] [Indexed: 11/30/2022]
Abstract
Salivary proteins modulate bacterial colonization in the oral cavity and interact with systemic pathogens that pass through the oropharynx. An interesting example is the opportunistic respiratory pathogen Streptococcus pneumoniae that normally resides in the nasopharynx, but belongs to the greater Mitis group of streptococci, most of which colonize the oral cavity. Streptococcus pneumoniae also expresses a serine-rich repeat (SRR) adhesin, PsrP, which is a homologue to oral Mitis group SRR adhesins, such as Hsa of Streptococcus gordonii and SrpA of Streptococcus sanguinis. As the latter bind to salivary glycoproteins through recognition of terminal sialic acids, we wanted to determine whether S. pneumoniae also binds to salivary proteins through possibly the same mechanism. We found that only a capsule-free mutant of S. pneumoniae TIGR4 binds to salivary proteins, most prominently to mucin MUC7, but that this binding was not mediated through PsrP or recognition of sialic acid. We also found, however, that PsrP is involved in agglutination of human red blood cells (RBCs). After removal of PsrP, an additional previously masked lectin-like adhesin activity mediating agglutination of sialidase-treated RBCs becomes revealed. Using a custom-spotted glycoprotein and neoglycoprotein dot blot array, we identify candidate glycan motifs recognized by PsrP and by the putative S. pneumoniae adhesin that could perhaps be responsible for pneumococcal binding to salivary MUC7 and glycoproteins on RBCs.
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Affiliation(s)
- Supaporn Thamadilok
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, NY 14214
| | - Hazeline Roche-Håkansson
- Department of Microbiology and Immunology, School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14214
| | - Anders P. Håkansson
- Department of Microbiology and Immunology, School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14214
| | - Stefan Ruhl
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, NY 14214
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Abstract
Staphylococcus aureus produces several virulence factors that allow it to cause a variety of infections. One of the major virulence factors is the capsule, which contributes to the survival of the pathogen within the host as a way to escape phagocytosis. The production of the capsular polysaccharide is encoded in a 16 gene operon, which is regulated in response to several environmental stimuli including nutrient availability. For instance, the capsule is produced in the late- and post-exponential growth phases, but not in the early- or mid-exponential growth phase. Several regulators are involved in capsule production, but the regulation of the cap operon is still poorly understood. In this study, we show that MsaB activates the cap operon by binding directly to a 10 bp repeat in the promoter region. We show that despite the fact that MsaB is expressed throughout four growth phases, it only activates capsule production in the late- and post-exponential growth phases. Furthermore, we find that MsaB does not bind to its target site in the early and mid-exponential growth phases. This correlates with decreased nutrient availability and capsule production. These data suggest either that MsaB binding ability changes in response to nutrients or that other cap operon regulators interfere with the binding of MsaB to its target site. This study increases our understanding of the regulation of capsule production and the mechanism of action of MsaB.
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Affiliation(s)
- Justin L Batte
- Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS, USA
| | - Dhritiman Samanta
- Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS, USA
| | - Mohamed O Elasri
- Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS, USA
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Ziane H, Manageiro V, Ferreira E, Bektache S, Tazir M, Caniça M. Capsular typing of Streptococcus pneumoniae isolated in an Algerian hospital using a new multiplex PCR-based scheme. J Microbiol Methods 2015; 119:243-6. [PMID: 26546733 DOI: 10.1016/j.mimet.2015.11.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [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: 08/07/2015] [Revised: 11/03/2015] [Accepted: 11/03/2015] [Indexed: 11/18/2022]
Abstract
We developed a new sequential multiplex-PCR-based typing scheme (MPBTS) for pneumococcal capsular classification. The serogroup/type of 37 control isolates obtained by the Quellung reaction, MPBTS, and nucleotide sequencing, were fully concordant. The serogroups/types of 75 invasive isolates determined by MPBTS, presented 100% specificity and 96% sensitivity, when compared with the Quellung reaction.
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Affiliation(s)
- Hanifa Ziane
- Service de Microbiologie Clinique, Centre Hospitalo-Universitaire Mustapha Bacha, Faculté de Médecine, Algiers, Algeria
| | - Vera Manageiro
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal; CECA-ICETA, Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto University, Oporto, Portugal.
| | - Eugénia Ferreira
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
| | - Soumia Bektache
- Service de Microbiologie Clinique, Centre Hospitalo-Universitaire Mustapha Bacha, Faculté de Médecine, Algiers, Algeria
| | - Mohamed Tazir
- Service de Microbiologie Clinique, Centre Hospitalo-Universitaire Mustapha Bacha, Faculté de Médecine, Algiers, Algeria
| | - Manuela Caniça
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
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50
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Rosen DA, Hilliard JK, Tiemann KM, Todd EM, Morley SC, Hunstad DA. Klebsiella pneumoniae FimK Promotes Virulence in Murine Pneumonia. J Infect Dis 2015; 213:649-58. [PMID: 26347570 DOI: 10.1093/infdis/jiv440] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [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: 05/22/2015] [Accepted: 08/10/2015] [Indexed: 11/15/2022] Open
Abstract
Klebsiella pneumoniae, a chief cause of nosocomial pneumonia, is a versatile and commonly multidrug-resistant human pathogen for which further insight into pathogenesis is needed. We show that the pilus regulatory gene fimK promotes the virulence of K. pneumoniae strain TOP52 in murine pneumonia. This contrasts with the attenuating effect of fimK on urinary tract virulence, illustrating that a single factor may exert opposing effects on pathogenesis in distinct host niches. Loss of fimK in TOP52 pneumonia was associated with diminished lung bacterial burden, limited innate responses within the lung, and improved host survival. FimK expression was shown to promote serum resistance, capsule production, and protection from phagocytosis by host immune cells. Finally, while the widely used K. pneumoniae model strain 43816 produces rapid dissemination and death in mice, TOP52 caused largely localized pneumonia with limited lethality, thereby providing an alternative tool for studying K. pneumoniae pathogenesis and control within the lung.
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Affiliation(s)
- David A Rosen
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Julia K Hilliard
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Kristin M Tiemann
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Elizabeth M Todd
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - S Celeste Morley
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri
| | - David A Hunstad
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri
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