mBio, Journal Year: 2021, Volume and Issue: 12(3)
Published: June 29, 2021
S. maltophilia is an increasingly important opportunistic pathogen. Inherently resistant to many antibiotics, often associated with lung infection, being, among other things, a complicating factor in cystic fibrosis patients.
Language: Английский
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
Citations
2
Proceedings of the National Academy of Sciences, Journal Year: 2021, Volume and Issue: 118(40)
Published: Sept. 29, 2021
Significance Previous studies have indicated that Gram-positive bacteria are not affected by type VI secretion serum (T6SS) intoxication. However, here we show Acinetobacter baumannii employs its T6SS to kill different bacteria. Furthermore, determined killing was dependent on Tse4, a bifunctional effector possessing lytic transglycosylase and endopeptidase activities. Tse4 represents broad family of modularly organized peptidoglycan-degrading effectors. In addition, D-lysine A. results in pH increase, which greatly enhances activity. These expand the range T6SS-mediated interbacterial interactions may shape composition bacterial communities context human microbiota polymicrobial infections.
Language: Английский
Citations
88
Frontiers in Microbiology, Journal Year: 2024, Volume and Issue: 15
Published: Feb. 26, 2024
Numerous bacterial species associate with plants through commensal, mutualistic, or parasitic association, affecting host physiology and health. The mechanism for such association is intricate involves the secretion of multiple biochemical substances dedicated protein systems called SS. Eleven SS pathways deliver factors enzymes in their immediate environment cells, as well competing microbial cells a contact-dependent independent fashion. These are instrumental competition, initiation infection, colonization, establishment (positive negative) organisms. role infection pathogenesis has been demonstrated several phytopathogens, including Agrobacterium, Xanthomonas, Ralstonia, Pseudomonas . Since there overlap mechanisms establishing plants, studies have investigated SSs interaction plant beneficial bacteria, symbiotic rhizobia growth bacteria (PGPB). Therefore, present review updates different required colonization rhizobia, Burkholderia, Pseudomonas, Herbaspirillum , etc., on inside which can lead to long-term association. Most like T3SS, T4SS, T5SS, T6SS antagonistic activity needed prevent microbes, ameliorate biotic stress produce successful colonization. Others chemotaxis, adherence, niche formation, suppression immune response establish mutualistic plants.
Language: Английский
Citations
9
Molecular Systems Biology, Journal Year: 2024, Volume and Issue: 20(6), P. 702 - 718
Published: April 24, 2024
Abstract The type VI secretion system (T6SS) is an important mediator of microbe–microbe and microbe–host interactions. Gram-negative bacteria use the T6SS to inject effectors (T6Es), which are usually proteins with toxic activity, into neighboring cells. Antibacterial have cognate immunity that neutralize self-intoxication. Here, we applied novel structural bioinformatic tools perform systematic discovery functional annotation T6Es their from a dataset 17,920 T6SS-encoding bacterial genomes. Using clustering, identified 517 putative T6E families, outperforming sequence-based clustering. We developed logistic regression model reliably quantify protein–protein interaction new T6E-immunity pairs, yielding candidate for 231 out families. used sensitive structure-based yielded annotations 51% again annotation. Next, validated four pairs using basic experiments in E. coli . In particular, showed Pfam domain DUF3289 homolog Colicin M DUF943 acts as its protein. Furthermore, discovered SleB, lytic transglycosylase, specific glutamate catalytic residue. Overall, this study applies pair discovery, provides extensive database annotated pairs.
Language: Английский
Citations
9
mLife, Journal Year: 2022, Volume and Issue: 1(1), P. 66 - 78
Published: March 1, 2022
Abstract The type VI secretion system (T6SS) is a double‐tubular nanomachine widely found in gram‐negative bacteria. Its spear‐like Hcp tube capable of penetrating neighboring cell for cytosol‐to‐cytosol protein delivery. However, gram‐positive bacteria have been considered impenetrable to such T6SS action. Here we report that the plant pathogen, Acidovorax citrulli (AC), could deliver an Rhs‐family nuclease effector RhsB kill not only but also Using bioinformatic, biochemical, and genetic assays, systematically identified T6SS‐secreted effectors determined crucial antibacterial effector. contains N‐terminal PAAR domain, middle Rhs unknown C‐terminal domain. subject self‐cleavage at both its N‐ domains requires upstream‐encoded chaperone EagT2 VgrG3. toxic C‐terminus exhibits DNase activities toxicity neutralized by either two downstream immunity proteins, RimB1 RimB2. Deletion rhsB significantly impairs ability killing Bacillus subtilis while ectopic expression proteins or RimB2 confers protection. We demonstrate AC can effectively outcompete Escherichia coli B. planta highly potent other bacterial fungal species. Collectively, these findings highlight greatly expanded capabilities modulating microbiome compositions complex environments.
Language: Английский
Citations
32
The ISME Journal, Journal Year: 2023, Volume and Issue: 17(7), P. 1052 - 1062
Published: April 24, 2023
Abstract Bacteria commonly face attacks from other strains using the type VI secretion system (T6SS), which acts like a molecular speargun to stab and intoxicate competitors. Here we show how bacteria can work together collectively defend themselves against these attacks. This project began with an outreach activity: while developing online computer game of bacterial warfare, noticed that one strategist (“Slimy”) made extracellular polymeric substances (EPS) was able resist another employed T6SS (“Stabby”). observation motivated us model this scenario more formally, dedicated agent-based simulations. The predicts EPS production serve as collective defence mechanism, protects both producing cells neighbouring do not make EPS. We then tested our synthetic community contains T6SS-wielding attacker (Acinetobacter baylyi), two T6SS-sensitive target (Escherichia coli) either secrete EPS, or not. As predicted by modelling, find leads protection attacks, where producers protect each nearby non-producers. identify processes explain protection: sharing between second general mechanism whereby groups resistant shield susceptible cells, call “flank protection”. Our shows EPS-producing system.
Language: Английский
Citations
21
Molecular Plant Pathology, Journal Year: 2024, Volume and Issue: 25(1)
Published: Jan. 1, 2024
Stenotrophomonas rhizophila CFBP13503 is a seedborne commensal bacterial strain, which efficiently transmitted to seedlings and can outcompete the phytopathogenic bacterium Xanthomonas campestris pv. (Xcc8004). The type VI secretion system (T6SS), an interference contact-dependent mechanism, critical component of interbacterial competition. involvement T6SS S. in inhibition Xcc8004 growth seed-to-seedling transmission was assessed. cluster nine putative effectors were identified. Deletion two structural genes, hcp tssB, abolished competitive advantage against vitro. population sizes these species monitored after inoculation radish seeds with mixtures either wild-type (wt) strain or isogenic mutant. A significant decrease size observed during confrontation wt comparison T6SS-deletion mutants germinated seedlings. We found that distribution among 835 genomes genus scarce. In contrast, all available genomes, clusters are widespread mainly belong group i4. conclusion, involved antibiosis reduces seedling radish. this complex could make it possible exploit strains as biocontrol agents X. campestris.
Language: Английский
Citations
6
mBio, Journal Year: 2024, Volume and Issue: 15(4)
Published: March 18, 2024
Bacterial competition may rely on secretion systems such as the type 6 system (T6SS), which punctures and releases toxic molecules into neighboring cells. To subsist, bacterial targets must counteract threats posed by T6SS-positive competitors. In this study, we used a comprehensive genome-wide high-throughput screening approach to investigate dynamics of interbacterial competition. Our primary goal was identify deletion mutants within well-characterized
Language: Английский
Citations
6
The ISME Journal, Journal Year: 2022, Volume and Issue: 16(7), P. 1765 - 1775
Published: March 30, 2022
Language: Английский
Citations
24
mBio, Journal Year: 2023, Volume and Issue: 14(1)
Published: Jan. 10, 2023
Acinetobacter baumannii is an increasing important nosocomial pathogen that difficult to combat due its ability survive in harsh environments and the emergence of isolates are resistant multiple antibiotics. A better understanding mechanism underlying toughness A. may identify Achilles’ heel, which will facilitate development novel preventive treatment measures.
Language: Английский
Citations
15