Multiplicity of type 6 secretion system toxins limits the evolution of resistance

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(2)

Published: Jan. 9, 2025

The bacterial type 6 secretion system (T6SS) is a toxin-injecting nanoweapon that mediates competition in plant- and animal-associated microbial communities. Bacteria can evolve de novo resistance against T6SS attacks, but far from universal natural communities, suggesting key features of weaponry may act to limit its evolution. Here, we combine ecoevolutionary modeling experimental evolution examine how toxin multiplicity Acinetobacter baylyi attackers shape susceptible Escherichia coli competitors. In both our models experiments, find combinations multiple distinct toxins by creating genetic bottlenecks, driving resistant lineages extinct before they reach high frequency. We also show that, paradoxically, single-toxin drive the cross-resistance, protecting bacteria unfamiliar combinations, even though such evolutionary pathways were inaccessible multitoxin attackers. Our findings indicate comparable antimicrobial anticancer combination therapies, arsenals function competing microbes. This helps us understand why T6SSs remain widespread effective weapons many T6SS-armed encode functionally diverse anticompetitor toxins.

Language: Английский

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Mechanisms of bacterial immunity, protection, and survival during interbacterial warfare

Cell Host & Microbe, Journal Year: 2024, Volume and Issue: 32(6), P. 794 - 803

Published: June 1, 2024

Most bacteria live in communities, often with closely related strains and species whom they must compete for space resources. Consequently, have acquired or evolved mechanisms to antagonize competitors through the production of antibacterial toxins. Similar bacterial systems that combat phage infection thwart antibiotics, also features protect themselves from Just as there is a large body research identifying characterizing proteins toxin delivery systems, studies resist survive assault competitors' weapons expanded tremendously. Emerging data are beginning reveal protective processes diverse toxins themselves. Protection against can be by horizontal gene transfer, receptor target alteration, induction functions, physical barriers, other processes. Here, we review recent this rapidly expanding field.

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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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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Pseudomonads coordinate innate defense against viruses and bacteria with a single regulatory system

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 27, 2025

Bacterial cells live under the constant existential threats imposed by other bacteria and viruses. Their mechanisms for contending with these are well documented; however, regulation of diverse defense elements remains poorly understood. Here we show that can mount a genome-wide, coordinated, highly effective immune response against bacterial viral using single regulatory pathway. Bioinformatic analyses revealed Pseudomonas species broadly possess specialized form Gac/Rsm pathway (GRP), which our prior work in aeruginosa implicated activating interbacterial antagonism to neighbor cell death. Proteomic studies comparing GRP-activated -inactivated strains derived from showed regulates large variable suite factors both phage threats. Focusing on P. protegens, identify profound phenotypic consequences multiple forms several phage. Together, results reveal bacteria, like more complex organisms, couple danger sensing activation an system antibacterial antiviral arms.

Language: Английский

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TssL2 of T6SS2 is required for mobility, biofilm formation, wrinkly phenotype formation, and virulence of Vibrio parahaemolyticus SH112

Applied Microbiology and Biotechnology, Journal Year: 2024, Volume and Issue: 108(1)

Published: Dec. 1, 2024

Language: Английский

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