Intestinal Bacteroides modulates inflammation, systemic cytokines, and microbial ecology via propionate in a mouse model of cystic fibrosis

mBio, Journal Year: 2024, Volume and Issue: 15(2)

Published: Jan. 5, 2024

The composition of the gut microbiome in persons with CF is correlated lung health outcomes, a phenomenon referred to as gut-lung axis. Here, we demonstrate that intestinal microbe Bacteroides decreases inflammation through production short-chain fatty acid propionate. Supplementing levels an animal model associated reduced systemic and reduction relative abundance opportunistically pathogenic group Escherichia / Shigella gut. Taken together, these data key role for microbially produced propionate modulating inflammation, microbial ecology, axis cystic fibrosis. These support potential probiotic CF.

Language: Английский

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Microbial collaborations and conflicts: unraveling interactions in the gut ecosystem

Gut Microbes, Journal Year: 2023, Volume and Issue: 16(1)

Published: Dec. 27, 2023

The human gut microbiota constitutes a vast and complex community of microorganisms. myriad microorganisms present in the intestinal tract exhibits highly intricate interactions, which play crucial role maintaining stability balance microbial ecosystem. These turn, influence overall health host. mammalian microbes have evolved wide range mechanisms to suppress or even eliminate their competitors for nutrients space. Simultaneously, extensive cooperative interactions exist among different optimize resource utilization enhance own fitness. This review will focus on competitive members discuss key modes actions, including bacterial secretion systems, bacteriocins, membrane vesicles (MVs) etc. Additionally, we summarize current knowledge often-overlooked positive within microbiota, showcase representative machineries. information serve as reference better understanding occurring environment. Understanding interaction dynamics competition cooperation is unraveling ecology communities. Targeted interventions aimed at modulating these may offer potential therapeutic strategies disease conditions.

Language: Английский

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Assembly of a unique membrane complex in type VI secretion systems of Bacteroidota

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Jan. 10, 2024

Abstract The type VI secretion system (T6SS) of Gram-negative bacteria inhibits competitor cells through contact-dependent translocation toxic effector proteins. In Proteobacteria, the T6SS is anchored to cell envelope a megadalton-sized membrane complex (MC). However, genomes Bacteroidota with T6SSs appear lack genes encoding homologs canonical MC components. Here, we identify five in Bacteroides fragilis ( tssNQOPR ) that are essential for function and encode Bacteroidota-specific MC. We purify this complex, reveal its dimensions using electron microscopy, protein-protein interaction network underlying assembly including stoichiometry TssNQOPR Protein TssN mediates connection between conserved baseplate. Although gene content organization varies across phylum Bacteroidota, no detected outside loci, suggesting ancient co-option functional convergence non-homologous Pseudomonadota.

Language: Английский

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Emerging models to study competitive interactions within bacterial communities

Trends in Microbiology, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Within both abiotic and host environments, bacteria typically exist as diverse, multispecies communities have crucial roles in human health, agriculture, industry. In these communities, compete for resources, competitive interactions can shape the overall population structure community function. Studying bacterial dynamics requires experimental model systems that capture different interaction networks between their surroundings. We examine recent literature advancing such systems, including (i) silico models establishing theoretical basis how cell-to-cell influence level dynamics, (ii) vitro characterizing specific interbacterial interactions, (iii) organ-on-a-chip revealing physiologically relevant parameters, spatial mechanical forces, encounter within a host, (iv) vivo plant animal connecting responses to interactions. Each of has greatly contributed our understanding be used synergistically understand competition influences architecture.

Language: Английский

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Interbacterial warfare in the human gut: insights from Bacteroidales’ perspective

Gut Microbes, Journal Year: 2025, Volume and Issue: 17(1)

Published: March 4, 2025

Competition and cooperation are fundamental to the stability evolution of ecological communities. The human gut microbiota, a dense complex microbial ecosystem, plays critical role in host's health disease, with competitive interactions being particularly significant. As dominant extensively studied group gut, Bacteroidales serves as successful model system for understanding these intricate dynamic processes. This review summarizes recent advances our antagonism mechanisms among at biochemical or molecular-genetic levels, focusing on interference exploitation competition. We also discuss unresolved questions suggest strategies studying Bacteroidales. presented here offers valuable insights into molecular basis bacterial may inform manipulating microbiome benefit health.

Language: Английский

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Mechanism of bacterial predation via ixotrophy

Science, Journal Year: 2024, Volume and Issue: 386(6719)

Published: Oct. 17, 2024

Ixotrophy is a contact-dependent predatory strategy of filamentous bacteria in aquatic environments for which the molecular mechanism remains unknown. We show that predator-prey contact can be established by gliding motility or extracellular assemblages we call "grappling hooks." Cryo-electron microscopy identified grappling hooks as heptamers type IX secretion system substrate. After close established, cryo-electron tomography and functional assays showed puncturing VI mediated killing. Single-cell analyses with stable isotope-labeled prey revealed components are taken up attacker. Depending on nutrient availability, insertion sequence elements toggle activity ixotrophy. A marine metagenomic time series shows coupled dynamics ixotrophic prey. found ixotrophy involves multiple cellular machineries, conserved, may shape microbial populations environment.

Language: Английский

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Interactions between pili affect the outcome of bacterial competition driven by the type VI secretion system

Current Biology, Journal Year: 2024, Volume and Issue: 34(11), P. 2403 - 2417.e9

Published: May 14, 2024

The bacterial type VI secretion system (T6SS) is a widespread, kin-discriminatory weapon capable of shaping microbial communities. Due to the system's dependency on contact, cellular interactions can lead either competition or kin protection. Cell-to-cell contact often accomplished via surface-exposed IV pili (T4Ps). In Vibrio cholerae, these T4Ps facilitate specific when bacteria colonize natural chitinous surfaces. However, it has remained unclear whether and, if so, how affect bacterium's T6SS-mediated killing. this study, we demonstrate that pilus-mediated be harnessed by T6SS-equipped V. cholerae kill non-kin cells under liquid growth conditions. We also show naturally occurring diversity determines likelihood cell-to-cell consequently, extent competition. To determine factors enable hinder T6SS's targeted reduction competitors carrying pili, developed physics-grounded computational model for autoaggregation. Collectively, our research demonstrates involved in impose selective burden encounters possess an active T6SS. Additionally, study underscores significance T4P protecting closely related individuals from T6SS attacks through autoaggregation and spatial segregation.

Language: Английский

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Competitive behaviors in Serratia marcescens are coordinately regulated by a lifestyle switch frequently inactivated in the clinical environment

Cell Host & Microbe, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Language: Английский

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Decoding resistance in the age of T6SS warfare

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(7)

Published: Feb. 10, 2025

Language: Английский

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Proteogenomic annotation of T6SS components identified in Bacteroides fragilis secretome

Frontiers in Microbiology, Journal Year: 2025, Volume and Issue: 16

Published: Feb. 11, 2025

Introduction Bacteroides fragilis (Bf)’s T6SS locus has been characterized and shown to have functional activity in competition experiments. It demonstrated that symbiont nontoxigenic Bf strains a more effective “weapon” effect on pathogenic Bf, which is realized through the of effector-immune (E-I) protein pairs. Intensive study structure led an understanding certain issues related its activity, but exact regulatory mechanisms E-I pair remain unclear. Proteomic annotation components detailed descriptions all immune-effector pairs are currently available. In this research, we performed proteogenomic analysis subsequent proteomic toxigenic BOB25. Material methods Fractionated cells, cultivated media vesicles were prepared for proteome by HPLC-MS/MS. Proteogenomic comparative genomic loci BOB25 carried out comparison with reference genomes following strains: JIM10, NCTC 9343 638R. Results According data obtained, represented types analysed samples. The identified culture cells: ClpV (TssH), TssK, TssC, TssB, Hcp (TssD), TetR. predicted effector AKA51715.1 (VU15_08315) was also detected media. greatest amount proteins, including protein, vesicle samples, observed TEM. Potential effectors, (VU15_08315), AKA51716.1 (VU15_08320), AKA51728.1 (VU15_08385) immune AKA51727.1 (VU15_08380), vesicles. Discussion presence proteins secretome indicates high without bacterial competition. possible used bacteria regulate population size altering different repertoires

Language: Английский

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