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Maritan E, Quagliariello A, Frago E, Patarnello T, Martino ME. The role of animal hosts in shaping gut microbiome variation. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230071. [PMID: 38497257 PMCID: PMC10945410 DOI: 10.1098/rstb.2023.0071] [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: 07/10/2023] [Accepted: 10/10/2023] [Indexed: 03/19/2024] Open
Abstract
Millions of years of co-evolution between animals and their associated microbial communities have shaped and diversified the nature of their relationship. Studies continue to reveal new layers of complexity in host-microbe interactions, the fate of which depends on a variety of different factors, ranging from neutral processes and environmental factors to local dynamics. Research is increasingly integrating ecosystem-based approaches, metagenomics and mathematical modelling to disentangle the individual contribution of ecological factors to microbiome evolution. Within this framework, host factors are known to be among the dominant drivers of microbiome composition in different animal species. However, the extent to which they shape microbiome assembly and evolution remains unclear. In this review, we summarize our understanding of how host factors drive microbial communities and how these dynamics are conserved and vary across taxa. We conclude by outlining key avenues for research and highlight the need for implementation of and key modifications to existing theory to fully capture the dynamics of host-associated microbiomes. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.
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Affiliation(s)
- Elisa Maritan
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020 Padova, Italy
| | - Andrea Quagliariello
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020 Padova, Italy
| | - Enric Frago
- CIRAD, UMR CBGP, INRAE, Institut Agro, IRD, Université Montpellier, 34398 Montpellier, France
| | - Tomaso Patarnello
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020 Padova, Italy
| | - Maria Elena Martino
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020 Padova, Italy
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2
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Cossart P, Hacker J, Holden DH, Normark S, Vogel J. Meeting report 'Microbiology 2023: from single cell to microbiome and host', an international interacademy conference in Würzburg. Microlife 2024; 5:uqae008. [PMID: 38665235 PMCID: PMC11044969 DOI: 10.1093/femsml/uqae008] [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] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024]
Abstract
On September 20-22 September 2023, the international conference 'Microbiology 2023: from single cell to microbiome and host' convened microbiologists from across the globe for a very successful symposium, showcasing cutting-edge research in the field. Invited lecturers delivered exceptional presentations covering a wide range of topics, with a major emphasis on phages and microbiomes, on the relevant bacteria within these ecosystems, and their multifaceted roles in diverse environments. Discussions also spanned the intricate analysis of fundamental bacterial processes, such as cell division, stress resistance, and interactions with phages. Organized by four renowned Academies, the German Leopoldina, the French Académie des sciences, the Royal Society UK, and the Royal Swedish Academy of Sciences, the symposium provided a dynamic platform for experts to share insights and discoveries, leaving participants inspired and eager to integrate new knowledge into their respective projects. The success of Microbiology 2023 prompted the decision to host the next quadrennial academic meeting in Sweden. This choice underscores the commitment to fostering international collaboration and advancing the frontiers of microbiological knowledge. The transition to Sweden promises to be an exciting step in the ongoing global dialogue and specific collaborations on microbiology, a field where researchers will continue to push the boundaries of knowledge, understanding, and innovation not only in health and disease but also in ecology.
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Affiliation(s)
| | - Jörg Hacker
- German National Academy of Science Leopoldina, Jägerberg 1, D-06108 Halle, Germany
| | - David H Holden
- Department of Infectious Disease, Centre for Bacterial Resistance Biology, Flowers Building, South Kensington Campus, Exhibition Road, Imperial College London, London SW7 2AZ, United Kingdom
| | - Staffan Normark
- Karolinska Institute, Tumor-och-cellbiologi, C1 Microbial Pathogenesis, 17177 Stockholm, Sweden
| | - Jörg Vogel
- Faculty of Medicine, Institute for Molecular Infection Biology (IMIB), University of Würzburg, D-97080 Würzburg, Germany
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), Josef-Schneider-Str2/Gebaude D15; É. D-97080 Würzburg, Germany
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3
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Hu T, Fang H, Pan Q, Xu H, Lv T, Fan X, Wang Y, Guo Y, Mou L, Xu J, Zhu J, Matsumoto H, Wang M. Seed microbiome-mediated herbicide resistance evolution in weeds. New Phytol 2024; 242:333-343. [PMID: 38062878 DOI: 10.1111/nph.19459] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 11/17/2023] [Indexed: 03/22/2024]
Abstract
See also the Commentary on this article by Zhang et al., 242: 327–330.
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Affiliation(s)
- Tingting Hu
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Hongda Fang
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Qianqian Pan
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Haorong Xu
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Tianxing Lv
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Xiaoyan Fan
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Yue Wang
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Yichun Guo
- Phytobiome Ecological Science & Technology, Shanghai, 200122, China
| | - Lei Mou
- Phytobiome Ecological Science & Technology, Shanghai, 200122, China
| | - Jiayu Xu
- Phytobiome Ecological Science & Technology, Shanghai, 200122, China
| | - Jinwen Zhu
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Haruna Matsumoto
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
| | - Mengcen Wang
- Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Pesticide and Environmental Toxicology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory of Rice Biology and Breeding, Zhejiang University, Hangzhou, 310058, China
- Global Education Program for AgriScience Frontiers, Graduate School of Agriculture, Hokkaido University, Sapporo, Japan
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Stante M, Weiland-Bräuer N, von Hoyningen-Huene AJE, Schmitz RA. Marine bacteriophages disturb the associated microbiota of Aurelia aurita with a recoverable effect on host morphology. Front Microbiol 2024; 15:1356337. [PMID: 38533338 PMCID: PMC10964490 DOI: 10.3389/fmicb.2024.1356337] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 02/21/2024] [Indexed: 03/28/2024] Open
Abstract
The concept of the metaorganism describes a multicellular host and its diverse microbial community, which form one biological unit with a combined genetic repertoire that significantly influences health and survival of the host. The present study delved into the emerging field of bacteriophage research within metaorganisms, focusing on the moon jellyfish Aurelia aurita as a model organism. The previously isolated Pseudomonas phage BSwM KMM1 and Citrobacter phages BSwM KMM2 - KMM4 demonstrated potent infectivity on bacteria present in the A. aurita-associated microbiota. In a host-fitness experiment, Baltic Sea subpopulation polyps were exposed to individual phages and a phage cocktail, monitoring polyp survival and morphology, as well as microbiome changes. The following effects were obtained. First, phage exposure in general led to recoverable malformations in polyps without affecting their survival. Second, analyses of the community structure, using 16S rRNA amplicon sequencing, revealed alterations in the associated microbial community in response to phage exposure. Third, the native microbiota is dominated by an uncultured likely novel Mycoplasma species, potentially specific to A. aurita. Notably, this main colonizer showed resilience through the recovery after initial declines, which aligned with abundance changes in Bacteroidota and Proteobacteria, suggesting a dynamic and adaptable microbial community. Overall, this study demonstrates the resilience of the A. aurita metaorganism facing phage-induced perturbations, emphasizing the importance of understanding host-phage interactions in metaorganism biology. These findings have implications for ecological adaptation and conservation in the rapidly changing marine environment, particularly regarding the regulation of blooming species and the health of marine ecosystems during ongoing environmental changes.
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Affiliation(s)
| | | | | | - Ruth Anne Schmitz
- Institute of General Microbiology, Christian-Albrechts University Kiel, Kiel, Germany
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Zhang YS, Zhang YQ, Zhao XM, Liu XL, Qin QL, Liu NH, Xu F, Chen XL, Zhang YZ, Li PY. Metagenomic insights into the dynamic degradation of brown algal polysaccharides by kelp-associated microbiota. Appl Environ Microbiol 2024; 90:e0202523. [PMID: 38259074 PMCID: PMC10880675 DOI: 10.1128/aem.02025-23] [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: 11/12/2023] [Accepted: 12/19/2023] [Indexed: 01/24/2024] Open
Abstract
Marine bacteria play important roles in the degradation and cycling of algal polysaccharides. However, the dynamics of epiphytic bacterial communities and their roles in algal polysaccharide degradation during kelp decay are still unclear. Here, we performed metagenomic analyses to investigate the identities and predicted metabolic abilities of epiphytic bacterial communities during the early and late decay stages of the kelp Saccharina japonica. During kelp decay, the dominant epiphytic bacterial communities shifted from Gammaproteobacteria to Verrucomicrobia and Bacteroidetes. In the early decay stage of S. japonica, epiphytic bacteria primarily targeted kelp-derived labile alginate for degradation, among which the gammaproteobacterial Vibrionaceae (particularly Vibrio) and Psychromonadaceae (particularly Psychromonas), abundant in alginate lyases belonging to the polysaccharide lyase (PL) families PL6, PL7, and PL17, were key alginate degraders. More complex fucoidan was preferred to be degraded in the late decay stage of S. japonica by epiphytic bacteria, predominantly from Verrucomicrobia (particularly Lentimonas), Pirellulaceae of Planctomycetes (particularly Rhodopirellula), Pontiellaceae of Kiritimatiellota, and Flavobacteriaceae of Bacteroidetes, which depended on using glycoside hydrolases (GHs) from the GH29, GH95, and GH141 families and sulfatases from the S1_15, S1_16, S1_17, and S1_25 families to depolymerize fucoidan. The pathways for algal polysaccharide degradation in dominant epiphytic bacterial groups were reconstructed based on analyses of metagenome-assembled genomes. This study sheds light on the roles of different epiphytic bacteria in the degradation of brown algal polysaccharides.IMPORTANCEKelps are important primary producers in coastal marine ecosystems. Polysaccharides, as major components of brown algal biomass, constitute a large fraction of organic carbon in the ocean. However, knowledge of the identities and pathways of epiphytic bacteria involved in the degradation process of brown algal polysaccharides during kelp decay is still elusive. Here, based on metagenomic analyses, the succession of epiphytic bacterial communities and their metabolic potential were investigated during the early and late decay stages of Saccharina japonica. Our study revealed a transition in algal polysaccharide-degrading bacteria during kelp decay, shifting from alginate-degrading Gammaproteobacteria to fucoidan-degrading Verrucomicrobia, Planctomycetes, Kiritimatiellota, and Bacteroidetes. A model for the dynamic degradation of algal cell wall polysaccharides, a complex organic carbon, by epiphytic microbiota during kelp decay was proposed. This study deepens our understanding of the role of epiphytic bacteria in marine algal carbon cycling as well as pathogen control in algal culture.
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Affiliation(s)
- Yi-Shuo Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Yu-Qi Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Xiang-Ming Zhao
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Xiao-Lei Liu
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Qi-Long Qin
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Ning-Hua Liu
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Fei Xu
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Xiu-Lan Chen
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Yu-Zhong Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
- MOE Key Laboratory of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System & College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
- Joint Research Center for Marine Microbiol Science and Technology, Shandong University and Ocean University of China, Qingdao, China
| | - Ping-Yi Li
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
- Joint Research Center for Marine Microbiol Science and Technology, Shandong University and Ocean University of China, Qingdao, China
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6
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Dosi A, Meziti A, Tounta E, Koemtzopoulos K, Komnenou A, Dendrinos P, Kormas K. Fecal and skin microbiota of two rescued Mediterranean monk seal pups during rehabilitation. Microbiol Spectr 2024; 12:e0280523. [PMID: 38084980 PMCID: PMC10783143 DOI: 10.1128/spectrum.02805-23] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 11/15/2023] [Indexed: 01/13/2024] Open
Abstract
IMPORTANCE This study showed that during the rehabilitation of two rescued Mediterranean monk seal pups (Monachus monachus), the skin and fecal bacterial communities showed similar succession patterns between the two individuals. This finding means that co-housed pups share their microbiomes, and this needs to be considered in cases of infection outbreaks and their treatment. The housing conditions, along with the feeding scheme and care protocols, including the admission of antibiotics as prophylaxis, probiotics, and essential food supplements, resulted in bacterial communities with no apparent pathogenic bacteria. This is the first contribution to the microbiome of the protected seal species of M. monachus and contributes to the animal's conservation practices through its microbiome.
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Affiliation(s)
- Aggeliki Dosi
- Department of Ichthyology and Aquatic Environment, University of Thessaly, Volos, Greece
| | - Alexandra Meziti
- Department of Ichthyology and Aquatic Environment, University of Thessaly, Volos, Greece
| | - Eleni Tounta
- MOm/Hellenic Society for the Study and Protection of the Monk Seal, Athens, Greece
| | - Kimon Koemtzopoulos
- MOm/Hellenic Society for the Study and Protection of the Monk Seal, Athens, Greece
| | - Anastasia Komnenou
- School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Panagiotis Dendrinos
- MOm/Hellenic Society for the Study and Protection of the Monk Seal, Athens, Greece
| | - Konstantinos Kormas
- Department of Ichthyology and Aquatic Environment, University of Thessaly, Volos, Greece
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Juge N. Microbe Profile: Ruminococcus gnavus: the yin and yang of human gut symbionts. Microbiology (Reading) 2023; 169. [PMID: 37622435 PMCID: PMC10482369 DOI: 10.1099/mic.0.001383] [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] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 08/03/2023] [Indexed: 08/26/2023]
Abstract
Graphical abstract
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Affiliation(s)
- Nathalie Juge
- Quadram Institute Bioscience, Food, Microbiome and Health Institute Strategic Programme, Norwich NR4 7UQ, UK
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Sen A, Nishimura T, Yoshimoto S, Yoshida K, Gotoh A, Katoh T, Yoneda Y, Hashimoto T, Xiao JZ, Katayama T, Odamaki T. Comprehensive analysis of metabolites produced by co-cultivation of Bifidobacterium breve MCC1274 with human iPS-derived intestinal epithelial cells. Front Microbiol 2023; 14:1155438. [PMID: 37125172 PMCID: PMC10133457 DOI: 10.3389/fmicb.2023.1155438] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 03/23/2023] [Indexed: 05/02/2023] Open
Abstract
Examining how host cells affect metabolic behaviors of probiotics is pivotal to better understand the mechanisms underlying the probiotic efficacy in vivo. However, studies to elucidate the interaction between probiotics and host cells, such as intestinal epithelial cells, remain limited. Therefore, in this study, we performed a comprehensive metabolome analysis of a co-culture containing Bifidobacterium breve MCC1274 and induced pluripotent stem cells (iPS)-derived small intestinal-like cells. In the co-culture, we observed a significant increase in several amino acid metabolites, including indole-3-lactic acid (ILA) and phenyllactic acid (PLA). In accordance with the metabolic shift, the expression of genes involved in ILA synthesis, such as transaminase and tryptophan synthesis-related genes, was also elevated in B. breve MCC1274 cells. ILA production was enhanced in the presence of purines, which were possibly produced by intestinal epithelial cells (IECs). These findings suggest a synergistic action of probiotics and IECs, which may represent a molecular basis of host-probiotic interaction in vivo.
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Affiliation(s)
- Akira Sen
- Next Generation Science Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan
- *Correspondence: Akira Sen,
| | - Tatsuki Nishimura
- Next Generation Science Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan
| | - Shin Yoshimoto
- Next Generation Science Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan
| | - Keisuke Yoshida
- Next Generation Science Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan
| | - Aina Gotoh
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Toshihiko Katoh
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Yasuko Yoneda
- Technology Research Laboratory, Shimadzu Corp., Kyoto, Japan
| | | | - Jin-Zhong Xiao
- Next Generation Science Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan
| | - Takane Katayama
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Toshitaka Odamaki
- Next Generation Science Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan
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Abstract
L-arginine (L-arg) is a versatile amino acid and a central intestinal metabolite in mammalian and microbial organisms. Thus, L-arg participates as precursor of multiple metabolic pathways in the regulation of cell division and growth. It also serves as a source of carbon, nitrogen, and energy or as a substrate for protein synthesis. Consequently, L-arg can simultaneously modify mammalian immune functions, intraluminal metabolism, intestinal microbiota, and microbial pathogenesis. While dietary intake, protein turnover or de novo synthesis usually supply L-arg in sufficient amounts, the expression of several key enzymes of L-arg metabolism can change rapidly and dramatically following inflammation, sepsis, or injury. Consequently, the availability of L-arg can be restricted due to increased catabolism, transforming L-arg into an essential amino acid. Here, we review the enzymatic pathways of L-arg metabolism in microbial and mammalian cells and their role in immune function, intraluminal metabolism, colonization resistance, and microbial pathogenesis in the gut.
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Affiliation(s)
- Björn Nüse
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Tim Holland
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Manfred Rauh
- Department of Pediatrics and Adolescent Medicine, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Roman G Gerlach
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Jochen Mattner
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
- Medical Immunology Campus Erlangen, FAUErlangen-Nürnberg, Erlangen, Germany
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10
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Abstract
Two-component systems are ubiquitous signaling mechanisms in bacteria that enable intracellular changes from extracellular cues. These bacterial regulatory systems couple external stimuli to control genetic expression via an autophosphorylation cascade that transduces membrane signals to intracellular locations, thereby allowing bacteria to rapidly adapt to the changing environmental conditions. Well known to control basic cellular processes, it is evident that two-component systems also exercise control over virulence traits, such as motility, secretion systems, and stress responses that impact the complex cascade of networks that alter virulence traits. In the gastrointestinal system, cues for activation of virulence-related two-component systems include metal ions, host-derived metabolites, and gut conditions. The diversity and origin of these cues suggest that the host can exert control over enteric pathogenicity via regulation in the gastrointestinal system. With the rise in multi-drug resistant pathogens, the potential control of pathogenicity with host cues via two-component systems presents a potential alternative to antimicrobials. Though the signaling mechanism itself is well studied, to date there is no systematic review compiling the host-associated cues of two-component systems and virulence traits. This review highlights the direct link between the host gastrointestinal environment and pathogenicity by focusing on two-component systems that are associated with the genetic expression of virulence traits, and that are activated by host-derived cues. The direct link between the host gastrointestinal environment, metabolites, and pathogenicity established in this review both underscores the importance of host-derived cues on bacterial activity and presents an enticing therapeutic target in the fight against antimicrobial resistant pathogens.
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Affiliation(s)
- Claire Shaw
- Department of Animal Science, Systems Microbiology & Natural Products Laboratory, University of California, Davis, USA
| | - Matthias Hess
- Department of Animal Science, Systems Microbiology & Natural Products Laboratory, University of California, Davis, USA
| | - Bart C Weimer
- Department of Population Health and Reproduction, 100K Pathogen Genome Project, University of California, Davis, CA, USA
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Heppert JK, Lickwar CR, Tillman MC, Davis BR, Davison JM, Lu HY, Chen W, Busch-Nentwich EM, Corcoran DL, Rawls JF. Conserved roles for Hnf4 family transcription factors in zebrafish development and intestinal function. Genetics 2022; 222:iyac133. [PMID: 36218393 PMCID: PMC9713462 DOI: 10.1093/genetics/iyac133] [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: 07/14/2022] [Accepted: 07/20/2022] [Indexed: 12/13/2022] Open
Abstract
Transcription factors play important roles in the development of the intestinal epithelium and its ability to respond to endocrine, nutritional, and microbial signals. Hepatocyte nuclear factor 4 family nuclear receptors are liganded transcription factors that are critical for the development and function of multiple digestive organs in vertebrates, including the intestinal epithelium. Zebrafish have 3 hepatocyte nuclear factor 4 homologs, of which, hnf4a was previously shown to mediate intestinal responses to microbiota in zebrafish larvae. To discern the functions of other hepatocyte nuclear factor 4 family members in zebrafish development and intestinal function, we created and characterized mutations in hnf4g and hnf4b. We addressed the possibility of genetic redundancy amongst these factors by creating double and triple mutants which showed different rates of survival, including apparent early lethality in hnf4a; hnf4b double mutants and triple mutants. RNA sequencing performed on digestive tracts from single and double mutant larvae revealed extensive changes in intestinal gene expression in hnf4a mutants that were amplified in hnf4a; hnf4g mutants, but limited in hnf4g mutants. Changes in hnf4a and hnf4a; hnf4g mutants were reminiscent of those seen in mice including decreased expression of genes involved in intestinal function and increased expression of cell proliferation genes, and were validated using transgenic reporters and EdU labeling in the intestinal epithelium. Gnotobiotics combined with RNA sequencing also showed hnf4g has subtler roles than hnf4a in host responses to microbiota. Overall, phenotypic changes in hnf4a single mutants were strongly enhanced in hnf4a; hnf4g double mutants, suggesting a conserved partial genetic redundancy between hnf4a and hnf4g in the vertebrate intestine.
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Affiliation(s)
- Jennifer K Heppert
- Department of Molecular Genetics and Microbiology, Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Medicine, Division of Gastroenterology and Hepatology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Colin R Lickwar
- Department of Molecular Genetics and Microbiology, Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710, USA
| | - Matthew C Tillman
- Department of Molecular Genetics and Microbiology, Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710, USA
| | - Briana R Davis
- Department of Molecular Genetics and Microbiology, Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710, USA
| | - James M Davison
- Department of Molecular Genetics and Microbiology, Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710, USA
| | - Hsiu-Yi Lu
- Department of Molecular Genetics and Microbiology, Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710, USA
| | - Wei Chen
- Center for Genomics and Computational Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | | | - David L Corcoran
- Center for Genomics and Computational Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - John F Rawls
- Department of Molecular Genetics and Microbiology, Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710, USA
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12
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Strong E, Hart B, Wang J, Orozco MG, Lee S. Induced Synthesis of Mycolactone Restores the Pathogenesis of Mycobacterium ulcerans In Vitro and In Vivo. Front Immunol 2022; 13:750643. [PMID: 35401531 PMCID: PMC8988146 DOI: 10.3389/fimmu.2022.750643] [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: 07/30/2021] [Accepted: 02/22/2022] [Indexed: 11/18/2022] Open
Abstract
Mycobacterium ulcerans is the causative agent of Buruli ulcer (BU), the third most common mycobacterial infection. Virulent M. ulcerans secretes mycolactone, a polyketide toxin. Most observations of M. ulcerans infection are described as an extracellular milieu in the form of a necrotic ulcer. While some evidence exists of an intracellular life cycle for M. ulcerans during infection, the exact role that mycolactone plays in this process is poorly understood. Many previous studies have relied upon the addition of purified mycolactone to cell-culture systems to study its role in M. ulcerans pathogenesis and host-response modulation. However, this sterile system drastically simplifies the M. ulcerans infection model and assumes that mycolactone is the only relevant virulence factor expressed by M. ulcerans. Here we show that the addition of purified mycolactone to macrophages during M. ulcerans infection overcomes the bacterial activation of the mechanistic target of rapamycin (mTOR) signaling pathway that plays a substantial role in regulating different cellular processes, including autophagy and apoptosis. To further study the role of mycolactone during M. ulcerans infection, we have developed an inducible mycolactone expression system. Utilizing the mycolactone-deficient Mul::Tn118 strain that contains a transposon insertion in the putative beta-ketoacyl transferase (mup045), we have successfully restored mycolactone production by expressing mup045 in a tetracycline-inducible vector system, which overcomes in-vitro growth defects associated with constitutive complementation. The inducible mycolactone-expressing bacteria resulted in the establishment of infection in a murine footpad model of BU similar to that observed during the infection with wild-type M. ulcerans. This mycolactone inducible system will allow for further analysis of the roles and functions of mycolactone during M. ulcerans infection.
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Affiliation(s)
- Emily Strong
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Bryan Hart
- Human Vaccine Institute, Duke University, Durham, NC, United States
| | - Jia Wang
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Maria Gonzalez Orozco
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Sunhee Lee
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
- Human Vaccine Institute, Duke University, Durham, NC, United States
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, United States
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13
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Mucci N, Chiarelli A, Lulli LG, Traversini V, Galea RP, Arcangeli G. WORKbiota: A Systematic Review about the Effects of Occupational Exposure on Microbiota and Workers' Health. Int J Environ Res Public Health 2022; 19:1043. [PMID: 35162072 DOI: 10.3390/ijerph19031043] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/14/2021] [Accepted: 01/13/2022] [Indexed: 12/12/2022]
Abstract
The characterization of human microbiota and the impact of its modifications on the health of individuals represent a current topic of great interest for the world scientific community. Scientific evidence is emerging regarding the role that microbiota has in the onset of important chronic illnesses. Since individuals spend most of their life at work, occupational exposures may have an impact on the organism’s microbiota. The purpose of this review is to explore the influence that different occupational exposures have on human microbiota in order to set a new basis for workers’ health protection and disease prevention. The literature search was performed in PubMed, Cochrane, and Scopus. A total of 5818 references emerged from the online search, and 31 articles were included in the systematic review (26 original articles and 5 reviews). Exposure to biological agents (in particular direct contact with animals) was the most occupational risk factor studied, and it was found involved in modifications of the microbiota of workers. Changes in microbiota were also found in workers exposed to chemical agents or subjected to work-related stress and altered dietary habits caused by specific microclimate characteristics or long trips. Two studies evaluated the role of microbiota changes on the development of occupational lung diseases. Occupational factors can interface with the biological rhythms of the bacteria of the microbiota and can contribute to its modifications and to the possible development of diseases. Future studies are needed to better understand the role of the microbiota and its connection with occupational exposure to promote projects for the prevention and protection of global health.
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14
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Bornet E, Westermann AJ. The ambivalent role of Bacteroides in enteric infections. Trends Microbiol 2021; 30:104-108. [PMID: 34893402 DOI: 10.1016/j.tim.2021.11.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 01/28/2023]
Abstract
Bacteroides spp. are increasingly used as model gut commensals in cocolonization studies with enteropathogens. The collective findings imply common themes of colonization resistance but also pathogen crossfeeding. We discuss how cutting-edge transcriptomics may help to disentangle the molecular basis of the divergent roles of Bacteroides in either protecting against or promoting infection.
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Affiliation(s)
- Elise Bornet
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), D-97080 Würzburg, Germany
| | - Alexander J Westermann
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), D-97080 Würzburg, Germany; Institute of Molecular Infection Biology (IMIB), University of Würzburg, D-97080 Würzburg, Germany.
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15
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Zhang X, Cai X, Zheng X. Gut microbiome-oriented therapy for metabolic diseases: challenges and opportunities towards clinical translation. Trends Pharmacol Sci 2021; 42:984-987. [PMID: 34579969 DOI: 10.1016/j.tips.2021.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/04/2021] [Accepted: 09/06/2021] [Indexed: 11/30/2022]
Abstract
Gut microbial changes have been causally associated with metabolic diseases, triggering huge interest in designing gut microbiome-based therapy. Here we discuss the open questions and challenges of translating ongoing gut microbiome-based intervention strategies to safe and efficacious clinical therapies. We also consider how the accumulating insights into host-microbe interactions in metabolic regulation could be harnessed as new dimensions to strengthen the translational prospect.
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Affiliation(s)
- Xueli Zhang
- Department of Pharmacy, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, China.
| | - Xiaoying Cai
- State Key Laboratory of Natural Medicines, College of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Xiao Zheng
- State Key Laboratory of Natural Medicines, College of Pharmacy, China Pharmaceutical University, Nanjing 210009, China.
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16
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Aires T, Stuij TM, Muyzer G, Serrão EA, Engelen AH. Characterization and Comparison of Bacterial Communities of an Invasive and Two Native Caribbean Seagrass Species Sheds Light on the Possible Influence of the Microbiome on Invasive Mechanisms. Front Microbiol 2021; 12:653998. [PMID: 34434172 PMCID: PMC8381869 DOI: 10.3389/fmicb.2021.653998] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 07/05/2021] [Indexed: 11/29/2022] Open
Abstract
Invasive plants, including marine macrophytes, are one of the most important threats to biodiversity by displacing native species and organisms depending on them. Invasion success is dependent on interactions among living organisms, but their study has been mostly limited to negative interactions while positive interactions are mostly underlooked. Recent studies suggested that microorganisms associated with eukaryotic hosts may play a determinant role in the invasion process. Along with the knowledge of their structure, taxonomic composition, and potential functional profile, understanding how bacterial communities are associated with the invasive species and the threatened natives (species-specific/environmentally shaped/tissue-specific) can give us a holistic insight into the invasion mechanisms. Here, we aimed to compare the bacterial communities associated with leaves and roots of two native Caribbean seagrasses (Halodule wrightii and Thalassia testudinum) with those of the successful invader Halophila stipulacea, in the Caribbean island Curaçao, using 16S rRNA gene amplicon sequencing and functional prediction. Invasive seagrass microbiomes were more diverse and included three times more species-specific core OTUs than the natives. Associated bacterial communities were seagrass-specific, with higher similarities between natives than between invasive and native seagrasses for both communities associated with leaves and roots, despite their strong tissue differentiation. However, with a higher number of OTUs in common, the core community (i.e., OTUs occurring in at least 80% of the samples) of the native H. wrightii was more similar to that of the invader H. stipulacea than T. testudinum, which could reflect more similar essential needs (e.g., nutritional, adaptive, and physiological) between native and invasive, in contrast to the two natives that might share more environment-related OTUs. Relative to native seagrass species, the invasive H. stipulacea was enriched in halotolerant bacterial genera with plant growth-promoting properties (like Halomonas sp. and Lysinibacillus sp.) and other potential beneficial effects for hosts (e.g., heavy metal detoxifiers and quorum sensing inhibitors). Predicted functional profiles also revealed some advantageous traits on the invasive species such as detoxification pathways, protection against pathogens, and stress tolerance. Despite the predictive nature of our findings concerning the functional potential of the bacteria, this investigation provides novel and important insights into native vs. invasive seagrasses microbiome. We demonstrated that the bacterial community associated with the invasive seagrass H. stipulacea is different from native seagrasses, including some potentially beneficial bacteria, suggesting the importance of considering the microbiome dynamics as a possible and important influencing factor in the colonization of non-indigenous species. We suggest further comparison of H. stipulacea microbiome from its native range with that from both the Mediterranean and Caribbean habitats where this species has a contrasting invasion success. Also, our new findings open doors to a more in-depth investigation combining meta-omics with bacterial manipulation experiments in order to confirm any functional advantage in the microbiome of this invasive seagrass.
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Affiliation(s)
- Tania Aires
- Centro de Ciências do Mar (CCMAR), Centro de Investigação Marinha e Ambiental (CIMAR), Universidade do Algarve, Faro, Portugal
| | - Tamara M Stuij
- Centro de Ciências do Mar (CCMAR), Centro de Investigação Marinha e Ambiental (CIMAR), Universidade do Algarve, Faro, Portugal.,CESAM - Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Aveiro, Portugal
| | - Gerard Muyzer
- Microbial Systems Ecology, Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - Ester A Serrão
- Centro de Ciências do Mar (CCMAR), Centro de Investigação Marinha e Ambiental (CIMAR), Universidade do Algarve, Faro, Portugal
| | - Aschwin H Engelen
- Centro de Ciências do Mar (CCMAR), Centro de Investigação Marinha e Ambiental (CIMAR), Universidade do Algarve, Faro, Portugal.,CARMABI Foundation, Willemstad, Curaçao
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17
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Franke M, Geier B, Hammel JU, Dubilier N, Leisch N. Coming together-symbiont acquisition and early development in deep-sea bathymodioline mussels. Proc Biol Sci 2021; 288:20211044. [PMID: 34403628 PMCID: PMC8370805 DOI: 10.1098/rspb.2021.1044] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [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: 05/04/2021] [Accepted: 07/26/2021] [Indexed: 11/16/2022] Open
Abstract
How and when symbionts are acquired by their animal hosts has a profound impact on the ecology and evolution of the symbiosis. Understanding symbiont acquisition is particularly challenging in deep-sea organisms because early life stages are so rarely found. Here, we collected early developmental stages of three deep-sea bathymodioline species from different habitats to identify when these acquire their symbionts and how their body plan adapts to a symbiotic lifestyle. These mussels gain their nutrition from chemosynthetic bacteria, allowing them to thrive at deep-sea vents and seeps worldwide. Correlative imaging analyses using synchrotron-radiation based microtomography together with light, fluorescence and electron microscopy revealed that the pediveliger larvae were aposymbiotic. Symbiont colonization began during metamorphosis from a planktonic to a benthic lifestyle, with the symbionts rapidly colonizing first the gills, the symbiotic organ of adults, followed by all other epithelia of their hosts. Once symbiont densities in plantigrades reached those of adults, the host's intestine changed from the looped anatomy typical for bivalves to a straightened form. Within the Mytilidae, this morphological change appears to be specific to Bathymodiolus and Gigantidas, and is probably linked to the decrease in the importance of filter feeding when these mussels switch to gaining their nutrition largely from their symbionts.
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Affiliation(s)
- Maximilian Franke
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
- MARUM—Zentrum für Marine Umweltwissenschaften, University of Bremen, Leobener Strasse 2, 28359 Bremen, Germany
| | - Benedikt Geier
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
| | - Jörg U. Hammel
- Helmholtz-Zentrum Hereon, Institute of Materials Physics, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
| | - Nicole Dubilier
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
- MARUM—Zentrum für Marine Umweltwissenschaften, University of Bremen, Leobener Strasse 2, 28359 Bremen, Germany
| | - Nikolaus Leisch
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
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18
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Abstract
Owing to their evolutionary potential, plant pathogens are able to rapidly adapt to genetically controlled plant resistance, often resulting in resistance breakdown and major epidemics in agricultural crops. Various deployment strategies have been proposed to improve resistance management. Globally, these rely on careful selection of resistance sources and their combination at various spatiotemporal scales (e.g., via gene pyramiding, crop rotations and mixtures, landscape mosaics). However, testing and optimizing these strategies using controlled experiments at large spatiotemporal scales are logistically challenging. Mathematical models provide an alternative investigative tool, and many have been developed to explore resistance deployment strategies under various contexts. This review analyzes 69 modeling studies in light of specific model structures (e.g., demographic or demogenetic, spatial or not), underlying assumptions (e.g., whether preadapted pathogens are present before resistance deployment), and evaluation criteria (e.g., resistance durability, disease control, cost-effectiveness). It highlights major research findings and discusses challenges for future modeling efforts.
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Affiliation(s)
- Loup Rimbaud
- INRAE, Pathologie Végétale, 84140 Montfavet, France; ,
- CSIRO Agriculture and Food, Canberra, ACT 2601, Australia; ,
| | - Frédéric Fabre
- INRAE, Bordeaux Sciences Agro, SAVE, 33882 Villenave d'Ornon, France;
| | | | - Benoît Moury
- INRAE, Pathologie Végétale, 84140 Montfavet, France; ,
| | | | - Luke G Barrett
- CSIRO Agriculture and Food, Canberra, ACT 2601, Australia; ,
| | - Peter H Thrall
- CSIRO Agriculture and Food, Canberra, ACT 2601, Australia; ,
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19
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Wheeler TB, Thompson V, Conner WR, Cooper BS. Wolbachia in the spittlebug Prosapia ignipectus: Variable infection frequencies, but no apparent effect on host reproductive isolation. Ecol Evol 2021; 11:10054-10065. [PMID: 34367558 PMCID: PMC8328426 DOI: 10.1002/ece3.7782] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/31/2021] [Accepted: 04/20/2021] [Indexed: 02/03/2023] Open
Abstract
Animals serve as hosts for complex communities of microorganisms, including endosymbionts that live inside their cells. Wolbachia bacteria are perhaps the most common endosymbionts, manipulating host reproduction to propagate. Many Wolbachia cause cytoplasmic incompatibility (CI), which results in reduced egg hatch when uninfected females mate with infected males. Wolbachia that cause intense CI spread to high and relatively stable frequencies, while strains that cause weak or no CI tend to persist at intermediate, often variable, frequencies. Wolbachia could also contribute to host reproductive isolation (RI), although current support for such contributions is limited to a few systems. To test for Wolbachia frequency variation and effects on host RI, we sampled several local Prosapia ignipectus (Fitch) (Hemiptera: Cercopidae) spittlebug populations in the northeastern United States over two years, including closely juxtaposed Maine populations with different monomorphic color forms, "black" and "lined." We discovered a group-B Wolbachia (wPig) infecting P. ignipectus that diverged from group-A Wolbachia-like model wMel and wRi strains in Drosophila-6 to 46 MYA. Populations of the sister species Prosapia bicincta (Say) from Hawaii and Florida are uninfected, suggesting that P. ignipectus acquired wPig after their initial divergence. wPig frequencies were generally high and variable among sites and between years. While phenotyping wPig effects on host reproduction is not currently feasible, the wPig genome contains three divergent sets of CI loci, consistent with high wPig frequencies. Finally, Maine monomorphic black and monomorphic lined populations of P. ignipectus share both wPig and mtDNA haplotypes, implying no apparent effect of wPig on the maintenance of this morphological contact zone. We hypothesize P. ignipectus acquired wPig horizontally as observed for many Drosophila species, and that significant CI and variable transmission produce high but variable wPig frequencies.
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Affiliation(s)
| | - Vinton Thompson
- Division of Invertebrate ZoologyAmerican Museum of Natural HistoryNew YorkNYUSA
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20
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Yoneda Y, Yamamoto K, Makino A, Tanaka Y, Meng XY, Hashimoto J, Shin-ya K, Satoh N, Fujie M, Toyama T, Mori K, Ike M, Morikawa M, Kamagata Y, Tamaki H. Novel Plant-Associated Acidobacteria Promotes Growth of Common Floating Aquatic Plants, Duckweeds. Microorganisms 2021; 9:1133. [PMID: 34074043 PMCID: PMC8225144 DOI: 10.3390/microorganisms9061133] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 05/20/2021] [Indexed: 11/17/2022] Open
Abstract
Duckweeds are small, fast growing, and starch- and protein-rich aquatic plants expected to be a next generation energy crop and an excellent biomaterial for phytoremediation. Despite such an importance, very little is known about duckweed-microbe interactions that would be a key biological factor for efficient industrial utilization of duckweeds. Here we first report the duckweed growth promoting ability of bacterial strains belonging to the phylum Acidobacteria, the members of which are known to inhabit soils and terrestrial plants, but their ecological roles and plant-microbe interactions remain largely unclear. Two novel Acidobacteria strains, F-183 and TBR-22, were successfully isolated from wild duckweeds and phylogenetically affiliated with subdivision 3 and 6 of the phylum, respectively, based on 16S rRNA gene sequence analysis. In the co-culture experiments with aseptic host plants, the F-183 and TBR-22 strains visibly enhanced growth (frond number) of six duckweed species (subfamily Lemnoideae) up to 1.8-5.1 times and 1.6-3.9 times, respectively, compared with uninoculated controls. Intriguingly, both strains also increased the chlorophyll content of the duckweed (Lemna aequinoctialis) up to 2.4-2.5 times. Under SEM observation, the F-183 and TBR-22 strains were epiphytic and attached to the surface of duckweed. Taken together, our findings suggest that indigenous plant associated Acidobacteria contribute to a healthy growth of their host aquatic plants.
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Affiliation(s)
- Yasuko Yoneda
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan; (Y.Y.); (K.Y.); (A.M.); (X.-Y.M.); (Y.K.)
| | - Kyosuke Yamamoto
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan; (Y.Y.); (K.Y.); (A.M.); (X.-Y.M.); (Y.K.)
- Bioproduction Research Institute, AIST, Sapporo 062-8517, Hokkaido, Japan
| | - Ayaka Makino
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan; (Y.Y.); (K.Y.); (A.M.); (X.-Y.M.); (Y.K.)
| | - Yasuhiro Tanaka
- Department of Environmental Sciences, Faculty of Life and Environmental Sciences, University of Yamanashi, Kofu 400-8510, Yamanashi, Japan;
| | - Xian-Ying Meng
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan; (Y.Y.); (K.Y.); (A.M.); (X.-Y.M.); (Y.K.)
| | - Junko Hashimoto
- Japan Biological Informatics Consortium (JBiC), Koto-ku, Tokyo 135-0064, Japan;
| | - Kazuo Shin-ya
- Cellular and Molecular Biotechnology Research Institute, AIST, Koto-ku, Tokyo 135-0064, Japan;
| | - Noriyuki Satoh
- Okinawa Institute of Science, Technology Graduate University (OIST), Kunigami-gun 904-0495, Okinawa, Japan; (N.S.); (M.F.)
| | - Manabu Fujie
- Okinawa Institute of Science, Technology Graduate University (OIST), Kunigami-gun 904-0495, Okinawa, Japan; (N.S.); (M.F.)
| | - Tadashi Toyama
- Department of Civil and Environmental Engineering, Faculty of Engineering, University of Yamanashi, Kofu 400-8511, Yamanashi, Japan; (T.T.); (K.M.)
| | - Kazuhiro Mori
- Department of Civil and Environmental Engineering, Faculty of Engineering, University of Yamanashi, Kofu 400-8511, Yamanashi, Japan; (T.T.); (K.M.)
| | - Michihiko Ike
- Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University, Suita 565-0871, Osaka, Japan;
| | - Masaaki Morikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Hokkaido, Japan;
| | - Yoichi Kamagata
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan; (Y.Y.); (K.Y.); (A.M.); (X.-Y.M.); (Y.K.)
| | - Hideyuki Tamaki
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan; (Y.Y.); (K.Y.); (A.M.); (X.-Y.M.); (Y.K.)
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8577, Ibaraki, Japan
- Microbiology Research Center for Sustainability (MiCS), University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
- Biotechnology Research Center, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan
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21
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Abstract
Heritable symbionts have diverse effects on the physiology, reproduction and fitness of their hosts. Maternally transmitted Wolbachia are one of the most common endosymbionts in nature, infecting about half of all insect species. We test the hypothesis that Wolbachia alter host behaviour by assessing the effects of 14 different Wolbachia strains on the locomotor activity of nine Drosophila host species. We find that Wolbachia alter the activity of six different host genotypes, including all hosts in our assay infected with wRi-like Wolbachia strains (wRi, wSuz and wAur), which have rapidly spread among Drosophila species in about the last 14 000 years. While Wolbachia effects on host activity were common, the direction of these effects varied unpredictably and sometimes depended on host sex. We hypothesize that the prominent effects of wRi-like Wolbachia may be explained by patterns of Wolbachia titre and localization within host somatic tissues, particularly in the central nervous system. Our findings support the view that Wolbachia have wide-ranging effects on host behaviour. The fitness consequences of these behavioural modifications are important for understanding the evolution of host-symbiont interactions, including how Wolbachia spread within host populations.
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Affiliation(s)
- Michael T. J. Hague
- Division of Biological Sciences, University of Montana, 32 Campus Dr., Missoula, MT 59812
| | - H. Arthur Woods
- Division of Biological Sciences, University of Montana, 32 Campus Dr., Missoula, MT 59812
| | - Brandon S. Cooper
- Division of Biological Sciences, University of Montana, 32 Campus Dr., Missoula, MT 59812
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22
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Petrova MI, Reid G, Ter Haar JA. Lacticaseibacillus rhamnosus GR-1, a.k.a. Lactobacillus rhamnosus GR-1: Past and Future Perspectives. Trends Microbiol 2021; 29:747-761. [PMID: 33865678 DOI: 10.1016/j.tim.2021.03.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 03/14/2021] [Accepted: 03/16/2021] [Indexed: 12/14/2022]
Abstract
Lacticaseibacillus rhamnosus GR-1 (LGR-1) (previously classified as Lactobacillus rhamnosus GR-1) is the most researched probiotic strain for women's health. Its various urogenital health effects, including a reduction in the recurrence of bacterial vaginosis and urinary-tract infection, are well documented. The strain has also been safely used by HIV-positive subjects, a portion of whom have reported reduced diarrhea and increased CD4 counts. Unlike most probiotic strains used for urogenital health, LGR-1 has been extensively studied for its properties, including its genomic and metabolic traits and its surface properties. This review aims to highlight the totality of research performed with LGR-1, to act as a rigorous scientific benchmark for probiotic microbes, especially for application to women's health.
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Affiliation(s)
- Mariya I Petrova
- Microbiome Insights and Probiotics Consultancy, Karlovo, Bulgaria.
| | - Gregor Reid
- Canadian Research and Development Centre for Human Microbiome and Probiotics, Lawson Health Research Institute, London, Canada; Department of Microbiology and Immunology, The University of Western Ontario, London, Canada; Department of Surgery, The University of Western Ontario, London, Canada
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23
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Guan XJ, Zhang YY, Zheng X, Hao HP. Drug Discovery Inspired from Nuclear Receptor Sensing of Microbial Signals. Trends Mol Med 2021; 27:624-6. [PMID: 33865719 DOI: 10.1016/j.molmed.2021.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/04/2021] [Accepted: 03/16/2021] [Indexed: 01/07/2023]
Abstract
Host-microbiota interactions are vital for diverse pathophysiological events and may be targeted for innovative therapeutics. Nuclear receptors (NRs) are versatile host sensors of microbial signals that coordinate diverse environmental cues with local and remote adaptions. Harnessing NR-mediated sensory machinery could provide an alternative lynchpin for gut microbiota-oriented drug discovery strategy.
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Saati-Santamaría Z, Rivas R, Kolařik M, García-Fraile P. A New Perspective of Pseudomonas-Host Interactions: Distribution and Potential Ecological Functions of the Genus Pseudomonas within the Bark Beetle Holobiont. Biology (Basel) 2021; 10:biology10020164. [PMID: 33669823 PMCID: PMC7922261 DOI: 10.3390/biology10020164] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/14/2021] [Accepted: 02/16/2021] [Indexed: 12/17/2022]
Abstract
Symbiosis between microbes and insects has been raised as a promising area for understanding biological implications of microbe-host interactions. Among them, the association between fungi and bark beetles has been generally recognized as essential for the bark beetle ecology. However, many works investigating bark beetle bacterial communities and their functions usually meet in a common finding: Pseudomonas is a broadly represented genus within this holobiont and it may provide beneficial roles to its host. Thus, we aimed to review available research on this microbe-host interaction and point out the probable relevance of Pseudomonas strains for these insects, in order to guide future research toward a deeper analysis of the importance of these bacteria for the beetle's life cycle.
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Affiliation(s)
- Zaki Saati-Santamaría
- Microbiology and Genetics Department, University of Salamanca, 37007 Salamanca, Spain;
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, 37185 Salamanca, Spain
- Correspondence: (Z.S.-S.); (P.G.-F.)
| | - Raúl Rivas
- Microbiology and Genetics Department, University of Salamanca, 37007 Salamanca, Spain;
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, 37185 Salamanca, Spain
- Associated Research Unit of Plant-Microorganism Interaction, USAL-CSIC (IRNASA), 37008 Salamanca, Spain
| | - Miroslav Kolařik
- Department of Botany, Faculty of Science, Charles University, 128 01 Prague, Czech Republic;
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Paula García-Fraile
- Microbiology and Genetics Department, University of Salamanca, 37007 Salamanca, Spain;
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, 37185 Salamanca, Spain
- Associated Research Unit of Plant-Microorganism Interaction, USAL-CSIC (IRNASA), 37008 Salamanca, Spain
- Correspondence: (Z.S.-S.); (P.G.-F.)
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Holmes A, Rossez Y, Wright KM, Hedley PE, Morris J, Willats WGT, Holden NJ. Escherichia coli O157:H7 F9 Fimbriae Recognize Plant Xyloglucan and Elicit a Response in Arabidopsis thaliana. Int J Mol Sci 2020; 21:E9720. [PMID: 33352760 DOI: 10.3390/ijms21249720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/04/2020] [Accepted: 12/14/2020] [Indexed: 11/16/2022] Open
Abstract
Fresh produce is often a source of enterohaemorrhagic Escherichia coli (EHEC) outbreaks. Fimbriae are extracellular structures involved in cell-to-cell attachment and surface colonisation. F9 (Fml) fimbriae have been shown to be expressed at temperatures lower than 37 °C, implying a function beyond the mammalian host. We demonstrate that F9 fimbriae recognize plant cell wall hemicellulose, specifically galactosylated side chains of xyloglucan, using glycan arrays. E. coli expressing F9 fimbriae had a positive advantage for adherence to spinach hemicellulose extract and tissues, which have galactosylated oligosaccharides as recognized by LM24 and LM25 antibodies. As fimbriae are multimeric structures with a molecular pattern, we investigated whether F9 fimbriae could induce a transcriptional response in model plant Arabidopsis thaliana, compared with flagella and another fimbrial type, E. coli common pilus (ECP), using DNA microarrays. F9 induced the differential expression of 435 genes, including genes involved in the plant defence response. The expression of F9 at environmentally relevant temperatures and its recognition of plant xyloglucan adds to the suite of adhesins EHEC has available to exploit the plant niche.
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Liu Y, Hou Y, Wang G, Zheng X, Hao H. Gut Microbial Metabolites of Aromatic Amino Acids as Signals in Host-Microbe Interplay. Trends Endocrinol Metab 2020; 31:818-834. [PMID: 32284282 DOI: 10.1016/j.tem.2020.02.012] [Citation(s) in RCA: 138] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 02/06/2023]
Abstract
Gut microbial metabolism is intimately coupled with host health and disease. Aromatic amino acid (AAA) catabolism by the gut microbiome yields numerous metabolites that may regulate immune, metabolic, and neuronal responses at local and distant sites. Such a chemical dialog between host cells and the gut microbiome is shaped by environmental cues, and may become dysregulated in gastrointestinal and systems diseases. Increasing knowledge of the bacterial pathway and signaling basis may shed additional light on metabolic host-microbiome crosstalk that remains untapped for drug discovery. Here, we update our understanding of microbial AAA metabolism and its impacts on host physiology and disease. We also consider open questions related to therapeutically mining these signaling metabolites and how recent concepts and tools may drive this area forward.
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Affiliation(s)
- Yali Liu
- Laboratory of Metabolism and Drug Target Discovery, State Key Laboratory of Natural Medicines, College of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Yuanlong Hou
- Laboratory of Metabolism and Drug Target Discovery, State Key Laboratory of Natural Medicines, College of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Guangji Wang
- Laboratory of Metabolism and Drug Target Discovery, State Key Laboratory of Natural Medicines, College of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Xiao Zheng
- Laboratory of Metabolism and Drug Target Discovery, State Key Laboratory of Natural Medicines, College of Pharmacy, China Pharmaceutical University, Nanjing, China.
| | - Haiping Hao
- Laboratory of Metabolism and Drug Target Discovery, State Key Laboratory of Natural Medicines, College of Pharmacy, China Pharmaceutical University, Nanjing, China.
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W Figueira L, de Oliveira JR, Netto AA, S Zamarioli LD, Marcucci MC, Camargo SE, de Oliveira LD. Curcuma longa L. helps macrophages to control opportunistic micro-organisms during host-microbe interactions. Future Microbiol 2020; 15:1237-1248. [PMID: 33026878 DOI: 10.2217/fmb-2019-0297] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: Plant products have been evaluated to control opportunistic micro-organisms, as well as fortify immune system cells. Thus, Curcuma longa L. (turmeric) extract was evaluated in interactions of murine macrophages (RAW 264.7) with Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans, in order to establish cooperation with defense cells. Materials & methods: Effects of minimal inhibitory concentrations (MIC) of the plant extract were analyzed on phagocytosis, cell viability of RAW 264.7 and production of inflammation-related molecules (IL-1β, TNF-α, IL-10 and NO). Results: The plant extract was cytocompatible and promoted significant reductions of micro-organisms, and synthesis of inflammation-related molecules, during interactions. Conclusion: C. longa L. extract showed significant antimicrobial response and cooperation with macrophages, by fighting bacteria and yeasts during host-microbe interactions.
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Affiliation(s)
- Leandro W Figueira
- Department of Biosciences & Oral Diagnosis, São Paulo State University (UNESP), Institute of Science & Technology, Av. Engenheiro Francisco José Longo, 777, São José dos Campos, SP 2245-000, Brazil
| | - Jonatas R de Oliveira
- Department of Biosciences & Oral Diagnosis, São Paulo State University (UNESP), Institute of Science & Technology, Av. Engenheiro Francisco José Longo, 777, São José dos Campos, SP 2245-000, Brazil.,School of Medicine, Anhembi Morumbi University, Av. Dep. Benedito Matarazzo, 4050, São José dos Campos, SP 12230-002, Brazil
| | - Amandio Al Netto
- Anhanguera University, Av. Raimundo Pereira de Magalhães, 3305. São Paulo, SP 05145-200, Brazil
| | - Lucas Dos S Zamarioli
- Department of Mode of Drug Action, Federal University of São Paulo (UNIFESP), Institute of Pharmacology & Molecular Biology, Rua Três de Maio, 100 São Paulo, SP 04044-020, Brazil
| | - Maria C Marcucci
- Anhanguera University, Av. Raimundo Pereira de Magalhães, 3305. São Paulo, SP 05145-200, Brazil
| | - Samira Ea Camargo
- Department of Restorative Dental Sciences, College of Dentistry, University of Florida, 1395 Center Drive, Gainesville, FL 32610, USA
| | - Luciane D de Oliveira
- Department of Biosciences & Oral Diagnosis, São Paulo State University (UNESP), Institute of Science & Technology, Av. Engenheiro Francisco José Longo, 777, São José dos Campos, SP 2245-000, Brazil
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Owens CE, Daniels KM, Ealy AD, Knowlton KF, Cockrum RR. Graduate Student Literature Review: Potential mechanisms of interaction between bacteria and the reproductive tract of dairy cattle. J Dairy Sci 2020; 103:10951-10960. [PMID: 32896395 DOI: 10.3168/jds.2019-18050] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 06/29/2020] [Indexed: 11/19/2022]
Abstract
Although the presence of bacteria has been characterized throughout the reproductive tracts of multiple species, how these bacteria may interact with the host has yet to be described. Previous reviews have described how pathogenic bacteria interact with the reproductive tract to cause infections such as metritis. This review aimed to summarize the knowledge related to pathogenic and nonpathogenic bacteria in various locations of the bovine reproductive tract and the possible mechanisms underlying host-microbe interactions during gametogenesis and early pregnancy. Lactic acid bacteria such as Lactobacillus seem to be beneficial in multiple areas of the reproductive tract: they have been associated with increased oocyte quality when in follicular fluid and secrete reactive oxygen species that are beneficial during placental angiogenesis. However, other bacteria, including Enterococcus, Staphylococcus, and Streptococcus, may modulate T helper cells that inhibit maternal recognition of pregnancy. Available data on the reproductive microbiome focus on variations in microbial communities and their associations with reproductive performance. However, research on these host-microbiome interactions may provide more insight on how bacteria affect fertility.
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Affiliation(s)
- C E Owens
- Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg 24061.
| | - K M Daniels
- Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg 24061
| | - A D Ealy
- Department of Animal and Poultry Science, Virginia Polytechnic Institute and State University, Blacksburg 24061
| | - K F Knowlton
- Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg 24061
| | - R R Cockrum
- Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg 24061
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Taubenheim J, Willoweit-Ohl D, Knop M, Franzenburg S, He J, Bosch TCG, Fraune S. Bacteria- and temperature-regulated peptides modulate β-catenin signaling in Hydra. Proc Natl Acad Sci U S A 2020; 117:21459-21468. [PMID: 32817436 PMCID: PMC7474684 DOI: 10.1073/pnas.2010945117] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Animal development has traditionally been viewed as an autonomous process directed by the host genome. But, in many animals, biotic and abiotic cues, like temperature and bacterial colonizers, provide signals for multiple developmental steps. Hydra offers unique features to encode these complex interactions of developmental processes with biotic and abiotic factors, and we used it here to investigate the impact of bacterial colonizers and temperature on the pattern formation process. In Hydra, formation of the head organizer involves the canonical Wnt pathway. Treatment with alsterpaullone (ALP) results in acquiring characteristics of the head organizer in the body column. Intriguingly, germfree Hydra polyps are significantly more sensitive to ALP compared to control polyps. In addition to microbes, β-catenin-dependent pattern formation is also affected by temperature. Gene expression analyses led to the identification of two small secreted peptides, named Eco1 and Eco2, being up-regulated in the response to both Curvibacter sp., the main bacterial colonizer of Hydra, and low temperatures. Loss-of-function experiments revealed that Eco peptides are involved in the regulation of pattern formation and have an antagonistic function to Wnt signaling in Hydra.
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Affiliation(s)
- Jan Taubenheim
- Zoology and Organismic Interactions, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- Zoological Institute, Christian-Albrechts University of Kiel, 24118 Kiel, Germany
| | - Doris Willoweit-Ohl
- Zoological Institute, Christian-Albrechts University of Kiel, 24118 Kiel, Germany
| | - Mirjam Knop
- Zoological Institute, Christian-Albrechts University of Kiel, 24118 Kiel, Germany
| | - Sören Franzenburg
- Institute of Clinical Molecular Biology, Christian-Albrechts University of Kiel, 24118 Kiel, Germany
| | - Jinru He
- Zoological Institute, Christian-Albrechts University of Kiel, 24118 Kiel, Germany
| | - Thomas C G Bosch
- Zoological Institute, Christian-Albrechts University of Kiel, 24118 Kiel, Germany
| | - Sebastian Fraune
- Zoology and Organismic Interactions, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
- Zoological Institute, Christian-Albrechts University of Kiel, 24118 Kiel, Germany
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Abstract
BACKGROUND Celiac disease is an autoimmune enteropathy characterized by an aberrant immune response to ingested gluten in genetically predisposed individuals. Studies have pointed to a rising prevalence of celiac disease in recent decades. Changes in diet and use of medication that may impact the gut microbiome have been suggested as potential contributors. Exposure to proton pump inhibitors (PPIs) was recently found to be associated with an increased risk for subsequent diagnosis of celiac disease. We aimed to investigate potential mechanisms for this link by examining the relationship between PPI use and gluten-related immune responses in the context of changes in gut microbiome. METHODS We performed a post hoc analysis of blood and fecal samples from a recent randomized trial in order to assess the potential association between PPI use and development of celiac disease serology in conjunction with alterations in gastrointestinal microbial composition. The study included 12 healthy participants who were administered a PPI (Omeprazole; 40 mg twice daily) for 4 or 8 weeks. RESULTS The analysis did not reveal an overall significant change in levels of serologic markers of celiac disease for the study cohort in response to PPI treatment. However, one individual developed a marked increase in the celiac disease-specific autoantibody response to transglutaminase 2 in conjunction with enhanced immune reactivity to gluten during the trial. Genotyping revealed positivity for the celiac disease-associated HLA-DQ2 and -DQ8 alleles. Furthermore, the observed elevation in antibody responses was closely associated with a sharp increase in fecal abundance of bacteria of the order Actinomycetales. CONCLUSIONS The results of this exploratory analysis support further investigation of molecular mechanisms involved in the contribution of PPIs to celiac disease risk through the potential enhancement of gluten immunopathology and changes in gut microbial population.
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Affiliation(s)
- Sophie Jang
- Department of Medicine
- Institute of Human Nutrition
| | - Benjamin Lebwohl
- Department of Medicine
- Celiac Disease Center
- Department of Epidemiology, Columbia University Irving Medical Center
| | - Julian A. Abrams
- Department of Medicine
- Department of Epidemiology, Columbia University Irving Medical Center
| | | | | | - Armin Alaedini
- Department of Medicine
- Institute of Human Nutrition
- Celiac Disease Center
- Department of Medicine, New York Medical College, Valhalla, New York
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Herrera P, Schuster L, Wentrup C, König L, Kempinger T, Na H, Schwarz J, Köstlbacher S, Wascher F, Zojer M, Rattei T, Horn M. Molecular causes of an evolutionary shift along the parasitism-mutualism continuum in a bacterial symbiont. Proc Natl Acad Sci U S A 2020; 117:21658-66. [PMID: 32817434 DOI: 10.1073/pnas.2005536117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Symbiotic relationships with microbes are ubiquitous among living beings and can be parasitic, such as in bacterial pathogens, or mutualistic, as in beneficial microbiomes. Among other factors, the outcome of microbe–host relationships is determined by the mode of symbiont transmission from host to host. Here we describe how bacterial symbionts increased in infectivity and virulence toward their amoeba host when transmission to a new host was essential for survival. The enhanced parasitism is a result of genomic changes and a pronounced switch of gene expression altering the symbionts’ mechanisms for host interaction. Our study provides both a molecular explanation as well as a blueprint for how changes in gene expression are sufficient to confer enhanced parasitism in microbes. Symbiosis with microbes is a ubiquitous phenomenon with a massive impact on all living organisms, shaping the world around us today. Theoretical and experimental studies show that vertical transmission of symbionts leads to the evolution of mutualistic traits, whereas horizontal transmission facilitates the emergence of parasitic features. However, these studies focused on phenotypic data, and we know little about underlying molecular changes at the genomic level. Here, we combined an experimental evolution approach with infection assays, genome resequencing, and global gene expression analysis to study the effect of transmission mode on an obligate intracellular bacterial symbiont. We show that a dramatic shift in the frequency of genetic variants, coupled with major changes in gene expression, allow the symbiont to alter its position in the parasitism–mutualism continuum depending on the mode of between-host transmission. We found that increased parasitism in horizontally transmitted chlamydiae residing in amoebae was a result of processes occurring at the infectious stage of the symbiont’s developmental cycle. Specifically, genes involved in energy production required for extracellular survival and the type III secretion system—the symbiont’s primary virulence mechanism—were significantly up-regulated. Our results identify the genomic and transcriptional dynamics sufficient to favor parasitic or mutualistic strategies.
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Scornec H, Palud A, Pédron T, Wheeler R, Petitgonnet C, Boneca IG, Cavin JF, Sansonetti PJ, Licandro H. Study of the cwaRS-ldcA Operon Coding a Two-Component System and a Putative L,D-Carboxypeptidase in Lactobacillus paracasei. Front Microbiol 2020; 11:156. [PMID: 32194510 PMCID: PMC7062640 DOI: 10.3389/fmicb.2020.00156] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 01/22/2020] [Indexed: 11/22/2022] Open
Abstract
The cell surface is the primary recognition site between the bacterium and the host. An operon of three genes, LSEI_0219 (cwaR), LSEI_0220 (cwaS), and LSEI_0221 (ldcA), has been previously identified as required for the establishment of Lactobacillus paracasei in the gut. The genes cwaR and cwaS encode a predicted two-component system (TCS) and ldcA a predicted D-alanyl-D-alanine carboxypeptidase which is a peptidoglycan (PG) biosynthesis enzyme. We explored the functionality and the physiological role of these three genes, particularly their impact on the bacterial cell wall architecture and on the bacterial adaptation to environmental perturbations in the gut. The functionality of CwaS/R proteins as a TCS has been demonstrated by biochemical analysis. It is involved in the transcriptional regulation of several genes of the PG biosynthesis. Analysis of the muropeptides of PG in mutants allowed us to re-annotate LSEI_0221 as a putative L,D-carboxypeptidase (LdcA). The absence of this protein coincided with a decrease of two surface antigens: LSEI_0020, corresponding to p40 or msp2 whose implication in the host epithelial homeostasis has been recently studied, and LSEI_2029 which has never been functionally characterized. The inactivation of each of these three genes induces susceptibility to antimicrobial peptides (hBD1, hBD2, and CCL20), which could be the main cause of the gut establishment deficiency. Thus, this operon is necessary for the presence of two surface antigens and for a suitable cell wall architecture.
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Affiliation(s)
- Hélène Scornec
- PAM UMR, AgroSup Dijon, Université de Bourgogne Franche-Comté, Dijon, France
| | - Aurore Palud
- PAM UMR, AgroSup Dijon, Université de Bourgogne Franche-Comté, Dijon, France
| | - Thierry Pédron
- Unité de Pathogénie Microbienne Moléculaire, Institut Pasteur, Paris, France
- Unité INSERM, Institut Pasteur, Paris, France
| | - Richard Wheeler
- Unité de Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
- Avenir Group, INSERM, Paris, France
| | - Clément Petitgonnet
- PAM UMR, AgroSup Dijon, Université de Bourgogne Franche-Comté, Dijon, France
| | - Ivo Gomperts Boneca
- Unité de Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
- Avenir Group, INSERM, Paris, France
| | - Jean-François Cavin
- PAM UMR, AgroSup Dijon, Université de Bourgogne Franche-Comté, Dijon, France
| | - Philippe J. Sansonetti
- Unité de Pathogénie Microbienne Moléculaire, Institut Pasteur, Paris, France
- Unité INSERM, Institut Pasteur, Paris, France
- Chaire de Microbiologie et Maladies Infectieuses, Collège de France, Paris, France
| | - Hélène Licandro
- PAM UMR, AgroSup Dijon, Université de Bourgogne Franche-Comté, Dijon, France
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Kumar Megta A, Palva A, von Ossowski I, Krishnan V. SpaB, an atypically adhesive basal pilin from the lactobacillar SpaCBA pilus: crystallization and X-ray diffraction analysis. Acta Crystallogr F Struct Biol Commun 2019; 75:731-737. [PMID: 31797814 PMCID: PMC6891582 DOI: 10.1107/s2053230x19015358] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 10/16/2019] [Accepted: 11/13/2019] [Indexed: 02/06/2023] Open
Abstract
The SpaB pilin is recognized as the basal subunit of the sortase-dependent SpaCBA pilus, which is known to be produced by the Gram-positive Lactobacillus rhamnosus GG, a gut-adapted commensal advocated to have health benefits. Despite seeming to function as an archetypal basal pilin by serving as the terminal subunit in pilus assembly, SpaB also assumes an atypical role as a mucoadhesive protein. To shed light on the structural factors that contribute to this dual functional behaviour, a recombinant form of the L. rhamnosus GG SpaB pilin was produced and purified for crystallization and X-ray diffraction experiments. The crystallization of SpaB remained particularly challenging until the implementation of a three-pronged crystallization approach involving C-terminal tail truncation, surface lysine methylation and magnesium additives. Ultimately, hexagonal crystals of SpaB were produced and were able to diffract to a resolution of 2.4 Å. This crystal form belonged to space group P6522 or P6122, with unit-cell parameters a = b = 51.53, c = 408.22 Å, α = β = 90.0, γ = 120.0°. Obtaining an interpretable electron-density map via single-wavelength anomalous diffraction (SAD) using iodide-derivative data sets did not succeed owing to the weak anomalous signal. As an alternative, attempts to provide phases by molecular replacement using the iodide-SAD data from SpaB and a collection of distant homology models (<28% sequence identity) are in progress.
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Affiliation(s)
- Abhin Kumar Megta
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana 121 001, India
- School of Biotechnology, KIIT University, Odisha 751 024, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Vengadesan Krishnan
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana 121 001, India
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Garcia JR, Larsen TJ, Queller DC, Strassmann JE. Fitness costs and benefits vary for two facultative Burkholderia symbionts of the social amoeba, Dictyostelium discoideum. Ecol Evol 2019; 9:9878-9890. [PMID: 31534701 PMCID: PMC6745654 DOI: 10.1002/ece3.5529] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 06/19/2019] [Accepted: 07/02/2019] [Indexed: 12/18/2022] Open
Abstract
Hosts and their associated microbes can enter into different relationships, which can range from mutualism, where both partners benefit, to exploitation, where one partner benefits at the expense of the other. Many host-microbe relationships have been presumed to be mutualistic, but frequently only benefits to the host, and not the microbial symbiont, have been considered. Here, we address this issue by looking at the effect of host association on the fitness of two facultative members of the Dictyostelium discoideum microbiome (Burkholderia agricolaris and Burkholderia hayleyella). Using two indicators of bacterial fitness, growth rate and abundance, we determined the effect of D. discoideum on Burkholderia fitness. In liquid culture, we found that D. discoideum amoebas lowered the growth rate of both Burkholderia species. In soil microcosms, we tracked the abundance of Burkholderia grown with and without D. discoideum over a month and found that B. hayleyella had larger populations when associating with D. discoideum while B. agricolaris was not significantly affected. Overall, we find that both B. agricolaris and B. hayleyella pay a cost to associate with D. discoideum, but B. hayleyella can also benefit under some conditions. Understanding how fitness varies in facultative symbionts will help us understand the persistence of host-symbiont relationships. OPEN RESEARCH BADGES This article has earned an Open Data Badge for making publicly available the digitally-shareable data necessary to reproduce the reported results. The data is available at https://openscholarship.wustl.edu/data/15/.
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Affiliation(s)
- Justine R. Garcia
- Department of BiologyWashington University in St. LouisSt. LouisMOUSA
- Present address:
Department of BiologyNew Mexico Highlands UniversityLas VegasNMUSA
| | - Tyler J. Larsen
- Department of BiologyWashington University in St. LouisSt. LouisMOUSA
| | - David C. Queller
- Department of BiologyWashington University in St. LouisSt. LouisMOUSA
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Viana F, Paz LC, Methling K, Damgaard CF, Lalk M, Schramm A, Lund MB. Distinct effects of the nephridial symbionts Verminephrobacter and Candidatus Nephrothrix on reproduction and maturation of its earthworm host Eisenia andrei. FEMS Microbiol Ecol 2019; 94:4768062. [PMID: 29272384 DOI: 10.1093/femsec/fix178] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 12/18/2017] [Indexed: 01/27/2023] Open
Abstract
Verminephrobacter, the most common specific symbionts in the nephridia (excretory organs) of lumbricid earthworms, have been shown to improve reproduction of the garden earthworm Aporrectodea tuberculata under nutrient limitation. It is unknown how general this beneficial trait is in the Verminephrobacter-earthworm symbiosis, whether other nephridial symbionts also affect host fitness and what the mechanism of the fitness increase is. Here we report beneficial effects of Verminephrobacter and Candidatus Nephrothrix on life history traits of the compost worm Eisenia andrei, which in addition to these two symbionts also hosts Agromyces-like bacteria in its mixed nephridial community: while growth was identical between control, Verminephrobacter-free and aposymbiotic worms, control worms produced significantly more cocoons and offspring than both Verminephrobacter-free and aposymbiotic worms, confirming the reproductive benefit of Verminephrobacter in a second host with different ecology and feeding behavior. Furthermore, worms with Verminephrobacter and Ca. Nephrothrix, or with only Ca. Nephrothrix present, reached sexual maturity significantly earlier than aposymbiotic worms; this is the first evidence for a beneficial role of Ca. Nephrothrix in earthworms. Riboflavin content in cocoons and whole earthworms was unaffected by the presence or absence of nephridial symbionts, suggesting that nutritional supplementation with this vitamin does not play a major role in this symbiosis.
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Affiliation(s)
- Flávia Viana
- Section for Microbiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | - Laura-Carlota Paz
- Section for Microbiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | - Karen Methling
- Institute of Biochemistry, Ernst-Moritz-Arndt-University Greifswald, 17487 Greifswald, Germany
| | - Christian F Damgaard
- Section for Plant and Insect Ecology, Department of Bioscience, Aarhus University, 8600 Silkeborg, Denmark
| | - Michael Lalk
- Institute of Biochemistry, Ernst-Moritz-Arndt-University Greifswald, 17487 Greifswald, Germany
| | - Andreas Schramm
- Section for Microbiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | - Marie B Lund
- Section for Microbiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, 8000 Aarhus, Denmark
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36
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Schroeder BO. Fight them or feed them: how the intestinal mucus layer manages the gut microbiota. Gastroenterol Rep (Oxf) 2019; 7:3-12. [PMID: 30792861 PMCID: PMC6375348 DOI: 10.1093/gastro/goy052] [Citation(s) in RCA: 250] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 11/29/2018] [Accepted: 12/13/2018] [Indexed: 02/06/2023] Open
Abstract
The intestinal tract is inhabited by a tremendous number of microorganisms, termed the gut microbiota. These microorganisms live in a mutualistic relationship with their host and assist in the degradation of complex carbohydrates. Although the gut microbiota is generally considered beneficial, the vast number of microbial cells also form a permanent threat to the host. Thus, the intestinal epithelium is covered with a dense layer of mucus to prevent translocation of the gut microbiota into underlying tissues. Intestinal mucus is an organized glycoprotein network with a host-specific glycan structure. While the mucus layer has long been considered a passive, host-designed barrier, recent studies showed that maturation and function of the mucus layer are strongly influenced by the gut microbiota. In return, the glycan repertoire of mucins can select for distinct mucosa-associated bacteria that are able to bind or degrade specific mucin glycans as a nutrient source. Because the intestinal mucus layer is at the crucial interface between host and microbes, its breakdown leads to gut bacterial encroachment that can eventually cause inflammation and infection. Accordingly, a dysfunctional mucus layer has been observed in colitis in mice and humans. Moreover, the increased consumption of a low-fiber Western-style diet in our modern society has recently been demonstrated to cause bacteria-mediated defects of the intestinal mucus layer. Here, I will review current knowledge on the interaction between gut bacteria and the intestinal mucus layer in health and disease. Understanding the molecular details of this host–microbe interaction may contribute to the development of novel treatment options for diseases involving a dysfunctional mucus layer, such as ulcerative colitis.
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Affiliation(s)
- Bjoern O Schroeder
- Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, Bruna Stråket 16, University of Gothenburg, SE 413 45 Gothenburg, Sweden
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37
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Abstract
Many Gram-negative bacterial pathogens directly deliver numerous effector proteins from the bacterium to the host cell, thereby altering the target cell physiology. The already well-characterized effector delivery systems are type III, type IV, and type VI secretion systems. Multifunctional autoprocessing repeats-in-toxin (MARTX) toxins are another effector delivery platform employed by some genera of Gram-negative bacteria. These single polypeptide exotoxins possess up to five effector domains in a modular fashion in their central regions. Upon binding to the host cell plasma membrane, MARTX toxins form a pore using amino- and carboxyl-terminal repeat-containing arms and translocate the effector domains into the cells. Consequently, MARTX toxins affect the integrity of the host cells and often induce cell death. Thus, they have been characterized as crucial virulence factors of certain human pathogens. This review covers how each of the MARTX toxin effector domains exhibits cytopathic and/or cytotoxic activities in cells, with their structural features revealed recently. In addition, future directions for the comprehensive understanding of MARTX toxin-mediated pathogenesis are discussed.
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Affiliation(s)
- Byoung Sik Kim
- Department of Food Science and Engineering, ELTEC College of Engineering, Ewha Womans University, Seoul 03760, Korea.
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38
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Abstract
In response to microbial infection, the human host deploys metal-sequestering host-defense proteins, which reduce nutrient availability and thereby inhibit microbial growth and virulence. Calprotectin (CP) is an abundant antimicrobial protein released from neutrophils and epithelial cells at sites of infection. CP sequesters divalent first-row transition metal ions to limit the availability of essential metal nutrients in the extracellular space. While functional and clinical studies of CP have been pursued for decades, advances in our understanding of its biological coordination chemistry, which is central to its role in the host-microbe interaction, have been made in more recent years. In this review, we focus on the coordination chemistry of CP and highlight studies of its metal-binding properties and contributions to the metal-withholding innate immune response. Taken together, these recent studies inform our current model of how CP participates in metal homeostasis and immunity, and they provide a foundation for further investigations of a remarkable metal-chelating protein at the host-microbe interface and beyond.
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Affiliation(s)
- Emily M Zygiel
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA;
| | - Elizabeth M Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA;
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Abstract
Mammalian innate and adaptive immune systems use the pattern recognition receptors, such as toll-like receptors, to detect conserved bacterial and viral components. Bacteria synthesize diverse D-amino acids while eukaryotes and archaea generally produce two D-amino acids, raising the possibility that many of bacterial D-amino acids are bacteria-specific metabolites. Although D-amino acids have not been identified to bind to any known pattern recognition receptors, D-amino acids are enantioselectively recognized by some other receptors and enzymes including a flavoenzyme D-amino acid oxidase (DAO) in mammals. At host-microbe interfaces in the neutrophils and intestinal mucosa, DAO catalyzes oxidation of bacterial D-amino acids, such as D-alanine, and generates H2O2, which is linked to antimicrobial activity. Intestinal DAO also modifies the composition of microbiota through modulation of growth for some bacteria that are dependent on host nutrition. Furthermore, regulation and recognition of D-amino acids in mammals have additional meanings at various host-microbe interfaces; D-phenylalanine and D-tryptophan regulate chemotaxis of neutrophils through a G-coupled protein receptor, D-serine has a bacteriostatic role in the urinary tract, D-phenylalanine and D-leucine inhibit innate immunity through the sweet taste receptor in the upper airway, and D-tryptophan modulates immune tolerance in the lower airway. This mini-review highlights recent evidence supporting the hypothesis that D-amino acids are utilized as inter-kingdom communication at host-microbe interface to modulate bacterial colonization and host defense.
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Affiliation(s)
- Jumpei Sasabe
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan
| | - Masataka Suzuki
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan
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40
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Stein RR, Tanoue T, Szabady RL, Bhattarai SK, Olle B, Norman JM, Suda W, Oshima K, Hattori M, Gerber GK, Sander C, Honda K, Bucci V. Computer-guided design of optimal microbial consortia for immune system modulation. eLife 2018; 7:e30916. [PMID: 29664397 PMCID: PMC5959721 DOI: 10.7554/elife.30916] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 03/31/2018] [Indexed: 02/07/2023] Open
Abstract
Manipulation of the gut microbiota holds great promise for the treatment of diseases. However, a major challenge is the identification of therapeutically potent microbial consortia that colonize the host effectively while maximizing immunologic outcome. Here, we propose a novel workflow to select optimal immune-inducing consortia from microbiome compositicon and immune effectors measurements. Using published and newly generated microbial and regulatory T-cell (Treg) data from germ-free mice, we estimate the contributions of twelve Clostridia strains with known immune-modulating effect to Treg induction. Combining this with a longitudinal data-constrained ecological model, we predict the ability of every attainable and ecologically stable subconsortium in promoting Treg activation and rank them by the Treg Induction Score (TrIS). Experimental validation of selected consortia indicates a strong and statistically significant correlation between predicted TrIS and measured Treg. We argue that computational indexes, such as the TrIS, are valuable tools for the systematic selection of immune-modulating bacteriotherapeutics.
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Affiliation(s)
- Richard R Stein
- cBio Center, Department of Biostatistics and Computational BiologyDana-Farber Cancer InstituteBostonUnited States
- Department of BiostatisticsHarvard T.H. Chan School of Public HealthBostonUnited States
- Department of Systems BiologyHarvard Medical SchoolBostonUnited States
- Broad Institute of MIT and HarvardCambridgeUnited States
| | - Takeshi Tanoue
- RIKEN Center for Integrative Medical SciencesYokohamaJapan
- Department of Microbiology and ImmunologyKeio University School of MedicineTokyoJapan
| | | | - Shakti K Bhattarai
- Engineering and Applied Sciences PhD ProgramUniversity of Massachusetts DartmouthNorth DartmouthUnited States
| | | | | | - Wataru Suda
- Department of Microbiology and ImmunologyKeio University School of MedicineTokyoJapan
- Graduate School of Frontier SciencesThe University of TokyoKashiwaJapan
| | - Kenshiro Oshima
- Graduate School of Frontier SciencesThe University of TokyoKashiwaJapan
| | - Masahira Hattori
- Graduate School of Frontier SciencesThe University of TokyoKashiwaJapan
| | - Georg K Gerber
- Massachusetts Host-Microbiome Center, Department of PathologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonUnited States
| | - Chris Sander
- cBio Center, Department of Biostatistics and Computational BiologyDana-Farber Cancer InstituteBostonUnited States
- Broad Institute of MIT and HarvardCambridgeUnited States
- Department of Cell BiologyHarvard Medical SchoolBostonUnited States
| | - Kenya Honda
- RIKEN Center for Integrative Medical SciencesYokohamaJapan
- Department of Microbiology and ImmunologyKeio University School of MedicineTokyoJapan
| | - Vanni Bucci
- Engineering and Applied Sciences PhD ProgramUniversity of Massachusetts DartmouthNorth DartmouthUnited States
- Department of BiologyUniversity of Massachusetts DartmouthNorth DartmouthUnited States
- Center for Microbial Informatics and StatisticsUniversity of Massachusetts DartmouthNorth DartmouthUnited States
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41
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Pogoreutz C, Rädecker N, Cárdenas A, Gärdes A, Wild C, Voolstra CR. Dominance of Endozoicomonas bacteria throughout coral bleaching and mortality suggests structural inflexibility of the Pocillopora verrucosa microbiome. Ecol Evol 2018; 8:2240-2252. [PMID: 29468040 PMCID: PMC5817147 DOI: 10.1002/ece3.3830] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 12/11/2017] [Accepted: 12/17/2017] [Indexed: 01/04/2023] Open
Abstract
The importance of Symbiodinium algal endosymbionts and a diverse suite of bacteria for coral holobiont health and functioning are widely acknowledged. Yet, we know surprisingly little about microbial community dynamics and the stability of host-microbe associations under adverse environmental conditions. To gain insight into the stability of coral host-microbe associations and holobiont structure, we assessed changes in the community structure of Symbiodinium and bacteria associated with the coral Pocillopora verrucosa under excess organic nutrient conditions. Pocillopora-associated microbial communities were monitored over 14 days in two independent experiments. We assessed the effect of excess dissolved organic nitrogen (DON) and excess dissolved organic carbon (DOC). Exposure to excess nutrients rapidly affected coral health, resulting in two distinct stress phenotypes: coral bleaching under excess DOC and severe tissue sloughing (>90% tissue loss resulting in host mortality) under excess DON. These phenotypes were accompanied by structural changes in the Symbiodinium community. In contrast, the associated bacterial community remained remarkably stable and was dominated by two Endozoicomonas phylotypes, comprising on average 90% of 16S rRNA gene sequences. This dominance of Endozoicomonas even under conditions of coral bleaching and mortality suggests the bacterial community of P. verrucosa may be rather inflexible and thereby unable to respond or acclimatize to rapid changes in the environment, contrary to what was previously observed in other corals. In this light, our results suggest that coral holobionts might occupy structural landscapes ranging from a highly flexible to a rather inflexible composition with consequences for their ability to respond to environmental change.
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Affiliation(s)
- Claudia Pogoreutz
- Red Sea Research Center, Biological and Environment Science and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
- Marine Ecology GroupFaculty of Biology and ChemistryUniversity of BremenBremenGermany
- Coral Reef Ecology GroupLeibniz Center for Tropical Marine Research (ZMT)BremenGermany
| | - Nils Rädecker
- Red Sea Research Center, Biological and Environment Science and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Anny Cárdenas
- Red Sea Research Center, Biological and Environment Science and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
- Tropical Marine Microbiology GroupLeibniz Center for Tropical Marine Research (ZMT)BremenGermany
| | - Astrid Gärdes
- Tropical Marine Microbiology GroupLeibniz Center for Tropical Marine Research (ZMT)BremenGermany
| | - Christian Wild
- Marine Ecology GroupFaculty of Biology and ChemistryUniversity of BremenBremenGermany
- Coral Reef Ecology GroupLeibniz Center for Tropical Marine Research (ZMT)BremenGermany
| | - Christian R. Voolstra
- Red Sea Research Center, Biological and Environment Science and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
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42
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Abstract
Multiple sclerosis (MS) is a chronic neuroinflammatory disease of the central nervous system with unknown etiology. Recently, the gut microbiota has emerged as a potential factor in the development of MS, with a number of studies having shown that patients with MS exhibit gut dysbiosis. The gut microbiota helps the host remain healthy by regulating various functions, including food metabolism, energy homeostasis, maintenance of the intestinal barrier, inhibition of colonization by pathogenic organisms, and shaping of both mucosal and systemic immune responses. Alteration of the gut microbiota, and subsequent changes in its metabolic network that perturb this homeostasis, may lead to intestinal and systemic disorders such as MS. Here we discuss the findings of recent MS microbiome studies and potential mechanisms through which gut microbiota can predispose to, or protect against, MS. These findings highlight the need of an improved understanding of the interactions between the microbiota and host for developing therapies based on gut commensals with which to treat MS.
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Affiliation(s)
- Samantha N Freedman
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Shailesh K Shahi
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Ashutosh K Mangalam
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA.
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.
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43
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Abstract
Wolbachia pipientis is an intracellular symbiont of arthropods well known for the reproductive manipulations induced in the host and, more recently, for the ability of Wolbachia to block virus replication in insect vectors. Since Wolbachia cannot yet be genetically manipulated, and due to the constraints imposed when working with an intracellular symbiont, little is known about mechanisms used by Wolbachia for host interaction. Here we employed a bioinformatics pipeline and identified 163 candidate effectors, potentially secreted by Wolbachia into the host cell. A total of 84 of these candidates were then subjected to a screen of growth defects induced in yeast upon heterologous expression which identified 14 top candidates likely secreted by Wolbachia. These predicted secreted effectors may function in concert as we find that their native expression is correlated and is highly upregulated at specific time points during Drosophila development. In addition, the evolutionary histories of some of these predicted effectors are also correlated, suggesting they may function together, or in the same pathway, during host infection. Similarly, most of these predicted effectors are limited to one or two Wolbachia strains—perhaps reflecting shared evolutionary history and strain specific functions in host manipulation. Identification of these Wolbachia candidate effectors is the first step in dissecting the mechanisms of symbiont–host interaction in this important system.
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Affiliation(s)
- Danny W Rice
- Department of Biology, Indiana University, Bloomington
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44
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Pajarillo EAB, Kim SH, Valeriano VD, Lee JY, Kang DK. Proteomic View of the Crosstalk between Lactobacillus mucosae and Intestinal Epithelial Cells in Co-culture Revealed by Q Exactive-Based Quantitative Proteomics. Front Microbiol 2017; 8:2459. [PMID: 29312173 PMCID: PMC5732961 DOI: 10.3389/fmicb.2017.02459] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/27/2017] [Indexed: 01/28/2023] Open
Abstract
Lactobacilli are bacteria that are beneficial to host health, but information on communication between Lactobacilli and host cells in the intestine is lacking. In this study, we examined the proteomes of the Lactobacillus mucosae strain LM1, as a model of beneficial bacteria, and the intestinal porcine epithelial cell line (IPEC-J2) after co-culture. Label-free proteomics demonstrated the high-throughput capability of the technique, and robust characterization of the functional profiles and changes in the bacteria and intestinal cells was achieved in pure and mixed cultures. After co-culture, we identified totals of 376 and 653 differentially expressed proteins in the LM1 and IPEC-J2 proteomes, respectively. The major proteomic changes in the LM1 strain occurred in the functional categories of transcription, general function, and translation, whereas those in IPEC-J2 cells involved metabolic and cellular processes, and cellular component organization/biogenesis. Among them, elongation factor Tu, glyceraldehyde 3-phosphate dehydrogenase, and phosphocarrier protein HPr, which are known to be involved in bacterial adhesion, were upregulated in LM1. In contrast, proteins involved in tight junction assembly, actin organization, and genetic information processing (i.e., histones and signaling pathways) were significantly upregulated in IPEC-J2 cells. Furthermore, we identified functional pathways that are possibly involved in host–microbe crosstalk and response. These findings will provide novel insights into host–bacteria communication and the molecular mechanism of probiotic establishment in the intestine.
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Affiliation(s)
| | - Sang Hoon Kim
- Department of Animal Resources Science, Dankook University, Cheonan, South Korea
| | | | - Ji Yoon Lee
- National Instrumentation Center for Environmental Management, Seoul National University, Seoul, South Korea
| | - Dae-Kyung Kang
- Department of Animal Resources Science, Dankook University, Cheonan, South Korea
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45
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Bryant WA, Stentz R, Le Gall G, Sternberg MJE, Carding SR, Wilhelm T. In Silico Analysis of the Small Molecule Content of Outer Membrane Vesicles Produced by Bacteroides thetaiotaomicron Indicates an Extensive Metabolic Link between Microbe and Host. Front Microbiol 2017; 8:2440. [PMID: 29276507 PMCID: PMC5727896 DOI: 10.3389/fmicb.2017.02440] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 11/24/2017] [Indexed: 11/15/2022] Open
Abstract
The interactions between the gut microbiota and its host are of central importance to the health of the host. Outer membrane vesicles (OMVs) are produced ubiquitously by Gram-negative bacteria including the gut commensal Bacteroides thetaiotaomicron. These vesicles can interact with the host in various ways but until now their complement of small molecules has not been investigated in this context. Using an untargeted high-coverage metabolomic approach we have measured the small molecule content of these vesicles in contrasting in vitro conditions to establish what role these metabolites could perform when packed into these vesicles. B. thetaiotaomicron packs OMVs with a highly conserved core set of small molecules which are strikingly enriched with mouse-digestible metabolites and with metabolites previously shown to be associated with colonization of the murine GIT. By use of an expanded genome-scale metabolic model of B. thetaiotaomicron and a potential host (the mouse) we have established many possible metabolic pathways between the two organisms that were previously unknown, and have found several putative novel metabolic functions for mouse that are supported by gene annotations, but that do not currently appear in existing mouse metabolic networks. The lipidome of these OMVs bears no relation to the mouse lipidome, so the purpose of this particular composition of lipids remains unclear. We conclude from this analysis that through intimate symbiotic evolution OMVs produced by B. thetaiotaomicron are likely to have been adopted as a conduit for small molecules bound for the mammalian host in vivo.
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Affiliation(s)
- William A. Bryant
- Centre for Integrative Systems Biology and Bioinformatics, Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Régis Stentz
- Gut Health and Food Safety Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Gwenaelle Le Gall
- Metabolomics Unit, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Michael J. E. Sternberg
- Centre for Integrative Systems Biology and Bioinformatics, Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Simon R. Carding
- Gut Health and Food Safety Programme, Quadram Institute Bioscience, Norwich, United Kingdom
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
| | - Thomas Wilhelm
- Theoretical Systems Biology Lab, Quadram Institute Bioscience, Norwich, United Kingdom
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Pietschke C, Treitz C, Forêt S, Schultze A, Künzel S, Tholey A, Bosch TCG, Fraune S. Host modification of a bacterial quorum-sensing signal induces a phenotypic switch in bacterial symbionts. Proc Natl Acad Sci U S A 2017; 114:E8488-97. [PMID: 28923926 DOI: 10.1073/pnas.1706879114] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Bacterial communities colonize epithelial surfaces of most animals. Several factors, including the innate immune system, mucus composition, and diet, have been identified as determinants of host-associated bacterial communities. Here we show that the early branching metazoan Hydra is able to modify bacterial quorum-sensing signals. We identified a eukaryotic mechanism that enables Hydra to specifically modify long-chain 3-oxo-homoserine lactones into their 3-hydroxy-HSL counterparts. Expression data revealed that Hydra's main bacterial colonizer, Curvibacter sp., responds differentially to N-(3-hydroxydodecanoyl)-l-homoserine lactone (3OHC12-HSL) and N-(3-oxododecanoyl)-l-homoserine lactone (3OC12-HSL). Investigating the impacts of the different N-acyl-HSLs on host colonization elucidated that 3OHC12-HSL allows and 3OC12-HSL represses host colonization of Curvibacter sp. These results show that an animal manipulates bacterial quorum-sensing signals and that this modification leads to a phenotypic switch in the bacterial colonizers. This mechanism may enable the host to manipulate the gene expression and thereby the behavior of its bacterial colonizers.
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Mishra AK, Megta AK, Palva A, von Ossowski I, Krishnan V. Crystallization and X-ray diffraction analysis of SpaE, a basal pilus protein from the gut-adapted Lactobacillus rhamnosus GG. Acta Crystallogr F Struct Biol Commun 2017; 73:321-327. [PMID: 28580919 PMCID: PMC5458388 DOI: 10.1107/s2053230x17006963] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [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: 04/06/2017] [Accepted: 05/09/2017] [Indexed: 12/19/2022] Open
Abstract
SpaE is the predicted basal pilin subunit in the sortase-dependent SpaFED pilus from the gut-adapted and commensal Lactobacillus rhamnosus GG. Thus far, structural characterization of the cell-wall-anchoring basal pilins has remained difficult and has been limited to only a few examples from pathogenic genera and species. To gain a further structural understanding of the molecular mechanisms that are involved in the anchoring and assembly of sortase-dependent pili in less harmful bacteria, L. rhamnosus GG SpaE for crystallization was produced by recombinant expression in Escherichia coli. Although several attempts to crystallize the SpaE protein were unsuccessful, trigonal crystals that diffracted to a resolution of 3.1 Å were eventually produced using PEG 3350 as a precipitant and high protein concentrations. Further optimization with a combination of additives led to the generation of SpaE crystals in an orthorhombic form that diffracted to a higher resolution of 1.5 Å. To expedite structure determination by SAD phasing, selenium-substituted (orthorhombic) SpaE crystals were grown and X-ray diffraction data were collected to 1.8 Å resolution.
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Affiliation(s)
- Arjun K. Mishra
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad 121 001, India
| | - Abhin Kumar Megta
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad 121 001, India
- School of Biotechnology, KIIT University, Odisha 751 024, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Vengadesan Krishnan
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad 121 001, India
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48
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Hiippala K, Kainulainen V, Kalliomäki M, Arkkila P, Satokari R. Mucosal Prevalence and Interactions with the Epithelium Indicate Commensalism of Sutterella spp. Front Microbiol 2016; 7:1706. [PMID: 27833600 PMCID: PMC5080374 DOI: 10.3389/fmicb.2016.01706] [Citation(s) in RCA: 186] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 10/12/2016] [Indexed: 12/25/2022] Open
Abstract
Sutterella species have been frequently associated with human diseases, such as autism, Down syndrome, and inflammatory bowel disease (IBD), but the impact of these bacteria on health still remains unclear. Especially the interactions of Sutterella spp. with the host are largely unknown, despite of the species being highly prevalent. In this study, we addressed the interaction of three known species of Sutterella with the intestinal epithelium and examined their adhesion properties, the effect on intestinal barrier function and the pro-inflammatory capacity in vitro. We also studied the relative abundance and prevalence of the genus Sutterella and Sutterella wadsworthensis in intestinal biopsies of healthy individuals and patients with celiac disease (CeD) or IBD. Our results show that Sutterella spp. are abundant in the duodenum of healthy adults with a decreasing gradient toward the colon. No difference was detected in the prevalence of Sutterella between the pediatric IBD or CeD patients and the healthy controls. Sutterella parvirubra adhered better than the two other Sutterella spp. to differentiated Caco-2 cells and was capable of decreasing the adherence of S. wadsworthensis, which preferably bound to mucus and human extracellular matrix proteins. Furthermore, only S. wadsworthensis induced an interleukin-8 production in enterocytes, which could be due to different lipopolysaccharide structures between the species. However, its pro-inflammatory activity was modest as compared to non-pathogenic Escherichia coli. Sutterella spp. had no effect on the enterocyte monolayer integrity in vitro. Our findings indicate that the members of genus Sutterella are widely prevalent commensals with mild pro-inflammatory capacity in the human gastrointestinal tract and do not contribute significantly to the disrupted epithelial homeostasis associated with microbiota dysbiosis and increase of Proteobacteria. The ability of Sutterella spp. to adhere to intestinal epithelial cells indicate that they may have an immunomodulatory role.
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Affiliation(s)
- Kaisa Hiippala
- Immunobiology Research Program, Faculty of Medicine, University of Helsinki Helsinki, Finland
| | - Veera Kainulainen
- Pharmacology, Faculty of Medicine, University of Helsinki Helsinki, Finland
| | - Marko Kalliomäki
- Department of Pediatrics, Turku University Central Hospital and Functional Foods Forum, University of Turku Turku, Finland
| | - Perttu Arkkila
- Department of Gastroenterology, Helsinki University Central Hospital Helsinki, Finland
| | - Reetta Satokari
- Immunobiology Research Program, Faculty of Medicine, University of Helsinki Helsinki, Finland
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Abstract
Inflammatory bowel diseases (IBDs) are chronic debilitating disorders of unknown etiology, consisting of two main conditions, ulcerative colitis and Crohn's disease. Major advances have recently taken place in human genetic studies of IBD and over 160 risk loci for these two diseases have been uncovered. These genetic data highlight a key role for genes that code for immunological and epithelial barrier functions. Environmental factors also make substantial contributions to the pathogenesis of IBD and account for the growing incidence of the diseases around the world. Intestinal microbiota creates resistance to infection, provides nutrients, and educates the immune system and in many ways has a significant impact on human health. Aberrant microbiota composition and decreased diversity (dysbiotic microbiota) are key etiopathological events in IBD. Dysbiotic microbiota can lead to loss of normal, regulatory immune effects in the gut mucosa. This may play a central role in the development and perpetuation of chronic inflammation. Further, the expression of specific innate immune receptors that recognize microbes is altered in the IBD epithelium. Therefore, the combination of host side epithelial barrier functions and the presence of dysbiotic microbiota in the gut together promote inflammation. New therapeutic options targeting microbiota are currently considered for IBD and they may, in the future, provide means to reverse the pathogenic host-microbiota relationship into a symbiotic one. In this review, the focus is on the intestinal microbiota and host-microbe interactions in IBD.
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Affiliation(s)
- Reetta Satokari
- Department of Veterinary Biosciences, University of Helsinki , Helsinki , Finland
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