The honeybee microbiota and its impact on health and disease

Nature Reviews Microbiology, Год журнала: 2023, Номер 22(3), С. 122 - 137

Опубликована: Дек. 4, 2023

Язык: Английский

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Cross-protection and cross-feeding between Klebsiella pneumoniae and Acinetobacter baumannii promotes their co-existence

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Фев. 9, 2023

Acinetobacter baumannii and Klebsiella pneumoniae are opportunistic pathogens frequently co-isolated from polymicrobial infections. The infections where these co-exist can be more severe recalcitrant to therapy than caused by either species alone, however there is a lack of knowledge on their potential synergistic interactions. In this study we characterise the genomes A. K. strains single human lung infection. We examine various aspects interactions through transcriptomic, phenomic phenotypic assays that form basis for understanding effects antimicrobial resistance virulence during co-infection. Using co-culturing analyses secreted metabolites, discover ability cross-feed by-products sugar fermentation. Minimum inhibitory concentration testing mono- co-cultures reveals cross-protect against cephalosporin, cefotaxime. Our demonstrates distinct syntrophic occur between pneumoniae, helping elucidate co-existence in

Язык: Английский

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

Proceedings of the National Academy of Sciences, Год журнала: 2025, Номер 122(2)

Опубликована: Янв. 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.

Язык: Английский

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SecReT6 update: a comprehensive resource of bacterial Type VI Secretion Systems

Science China Life Sciences, Год журнала: 2022, Номер 66(3), С. 626 - 634

Опубликована: Ноя. 4, 2022

Язык: Английский

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Killing in the name of: T6SS structure and effector diversity

Microbiology, Год журнала: 2023, Номер 169(7)

Опубликована: Июль 25, 2023

The life of bacteria is challenging, to endure employ a range mechanisms optimize their environment, including deploying the type VI secretion system (T6SS). Acting as bacterial crossbow, this delivers effectors responsible for subverting host cells, killing competitors and facilitating general access common goods. Due its importance, lethal machine has been evolutionarily maintained, disseminated specialized fulfil these vital functions. In fact, T6SS structural clusters are present in over 25 % Gram-negative bacteria, varying number from one six different genetic per organism. Since discovery 2006, research on rapidly progressed, yielding remarkable breakthroughs. identification characterization novel components T6SS, combined with biochemical studies, have revealed fascinating governing assembly, loading, firing disassembly processes. Recent findings also demonstrated efficacy against fungal Gram-positive expanding scope. Ongoing continues uncover an extensive repertoire effectors, genuine mediators function. These studies shedding light new aspects biology prokaryotic eukaryotic organisms. This review provides comprehensive overview highlighting recent discoveries structure diversity effectors. Additionally, it injects personal perspective avenues future research, aiming deepen our understanding combative system.

Язык: Английский

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Identification of type VI secretion system effector-immunity pairs using structural bioinformatics

Molecular Systems Biology, Год журнала: 2024, Номер 20(6), С. 702 - 718

Опубликована: Апрель 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.

Язык: Английский

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Soil microbiome bacteria protect plants against filamentous fungal infections via intercellular contacts

Proceedings of the National Academy of Sciences, Год журнала: 2025, Номер 122(3)

Опубликована: Янв. 15, 2025

Bacterial–fungal interaction (BFI) has significant implications for the health of host plants. While diffusible antibiotic metabolite-mediated competition in BFI been extensively characterized, impact intercellular contact remains largely elusive. Here, we demonstrate that is a prevalent mode between beneficial soil bacteria and pathogenic filamentous fungi. By generating antibiotics-deficient mutants two common bacteria, Lysobacter enzymogenes Pseudomonas fluorescens , show antibiotics-independent effectively inhibits Furthermore, transcriptional genetic evidence revealed this relies on mediated by type VI secretion system (T6SS), which may facilitate translocation bacterial toxic effectors into fungal cells. Finally, using “conidia enrichment” platform, found T6SS-mediated inhibition resulting from naturally occurs within microbiome, particularly represented fulva . Overall, these results microbiome can protect plants infection through contacts, thus revealing occurring ecologically important agricultural contexts.

Язык: Английский

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Whole-genome sequencing of Acinetobacter baumannii clinical isolates from a tertiary hospital in Terengganu, Malaysia (2011–2020), revealed the predominance of the Global Clone 2 lineage

Microbial Genomics, Год журнала: 2025, Номер 11(2)

Опубликована: Фев. 5, 2025

Carbapenem-resistant Acinetobacter baumannii is recognized by the World Health Organization (WHO) as one of top priority pathogens. Despite its public health importance, genomic data clinical isolates from Malaysia remain scarce. In this study, whole-genome sequencing was performed on 126 A . collected main tertiary hospital in state Terengganu, Malaysia, over a 10-year period (2011–2020). Antimicrobial susceptibilities determined for 20 antibiotics belonging to 8 classes showed that 77.0% ( n =97/126) were categorized multidrug resistant (MDR), with all MDR being carbapenem resistant. Multilocus sequence typing analysis Terengganu A. into 34 Pasteur and 44 Oxford types (STs), ST2 Global Clone 2 lineage identified dominant ST =76/126; 60.3%). The could be subdivided six STs majority ST195 =35) ST208 =17). Various antimicrobial resistance genes bla OXA-23 -encoded carbapenemase predominant acquired gene =90/126; 71.4%). Plasmid-encoded rep nearly =122/126; 96.8%) Rep_3 family =121). virulence factors identified, highlighting pathogenic nature bacterium. Only 14/126 (11.1%) positive carriage CRISPR-Cas arrays none prevalent harbouring them. This study provided snapshot obtained single healthcare centre predominance closely related lineage, indicating entrenchment clone hospital.

Язык: Английский

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Delivery of an Rhs‐family nuclease effector reveals direct penetration of the gram‐positive cell envelope by a type VI secretion system in Acidovorax citrulli

mLife, Год журнала: 2022, Номер 1(1), С. 66 - 78

Опубликована: Март 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.

Язык: Английский

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Presence and absence of type VI secretion systems in bacteria

Microbiology, Год журнала: 2022, Номер 168(4)

Опубликована: Апрель 8, 2022

The type VI secretion system (T6SS) is a molecular puncturing device that enables Gram-negative bacteria to kill competitors, manipulate host cells and take up nutrients. Who would want miss such superpowers? Indeed, many studies show how widespread the apparatus among microbes. However, it becoming evident that, on multiple taxonomic levels, from phyla species strains, some lack T6SS. Here, we review who does not have speculate dynamic process of gaining losing better understand its spread distribution across microbial world.

Язык: Английский

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