Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 8.999
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Cell Host Microbe ; 32(5): 634-636, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38723602

RESUMO

Bacterial genomes are littered with exogenous: competing DNA elements. Here, Sprenger et al. demonstrate that the Vibrio cholerae prophage VP882 modulates host functions via production of regulatory sRNAs to promote phage development. Alternatively, host sRNAs inhibit the VP882 lytic phase by specifically regulating phage genes.


Assuntos
Prófagos , Vibrio cholerae , Vibrio cholerae/genética , Prófagos/genética , Prófagos/fisiologia , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , Genoma Bacteriano , Bacteriófagos/genética , Bacteriófagos/fisiologia , Regulação Bacteriana da Expressão Gênica , RNA Bacteriano/genética , RNA Bacteriano/metabolismo
2.
Biochem Biophys Res Commun ; 716: 150030, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704889

RESUMO

Sugar phosphates are potential sources of carbon and phosphate for bacteria. Despite that the process of internalization of Glucose-6-Phosphate (G6P) through plasma membrane remained elusive in several bacteria. VCA0625-27, made of periplasmic ligand binding protein (PLBP) VCA0625, an atypical monomeric permease VCA0626, and a cytosolic ATPase VCA0627, recently emerged as hexose-6-phosphate uptake system of Vibrio cholerae. Here we report high resolution crystal structure of VCA0625 in G6P bound state that largely resembles AfuA of Actinobacillus pleuropneumoniae. MD simulations on VCA0625 in apo and G6P bound states unraveled an 'open to close' and swinging bi-lobal motions, which are diminished upon G6P binding. Mutagenesis followed by biochemical assays on VCA0625 underscored that R34 works as gateway to bind G6P. Although VCA0627 binds ATP, it is ATPase deficient in the absence of VCA0625 and VCA0626, which is a signature phenomenon of type-I ABC importer. Further, modeling, docking and systematic sequence analysis allowed us to envisage the existence of similar atypical type-I G6P importer with fused monomeric permease in 27 other gram-negative bacteria.


Assuntos
Proteínas de Bactérias , Glucose-6-Fosfato , Vibrio cholerae , Vibrio cholerae/metabolismo , Vibrio cholerae/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Cristalografia por Raios X , Glucose-6-Fosfato/metabolismo , Glucose-6-Fosfato/química , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/genética , Simulação de Dinâmica Molecular , Conformação Proteica , Modelos Moleculares , Ligação Proteica , Sítios de Ligação
3.
ACS Biomater Sci Eng ; 10(5): 2956-2966, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38593061

RESUMO

Bacteria experience substantial physical forces in their natural environment, including forces caused by osmotic pressure, growth in constrained spaces, and fluid shear. The cell envelope is the primary load-carrying structure of bacteria, but the mechanical properties of the cell envelope are poorly understood; reports of Young's modulus of the cell envelope of Escherichia coli range from 2 to 18 MPa. We developed a microfluidic system to apply mechanical loads to hundreds of bacteria at once and demonstrated the utility of the approach for evaluating whole-cell stiffness. Here, we extend this technique to determine Young's modulus of the cell envelope of E. coli and of the pathogens Vibrio cholerae and Staphylococcus aureus. An optimization-based inverse finite element analysis was used to determine the cell envelope Young's modulus from observed deformations. The Young's modulus values of the cell envelope were 2.06 ± 0.04 MPa for E. coli, 0.84 ± 0.02 MPa for E. coli treated with a chemical (A22) known to reduce cell stiffness, 0.12 ± 0.03 MPa for V. cholerae, and 1.52 ± 0.06 MPa for S. aureus (mean ± SD). The microfluidic approach allows examination of hundreds of cells at once and is readily applied to Gram-negative and Gram-positive organisms as well as rod-shaped and cocci cells, allowing further examination of the structural causes behind differences in cell envelope Young's modulus among bacterial species and strains.


Assuntos
Módulo de Elasticidade , Escherichia coli , Staphylococcus aureus , Vibrio cholerae , Staphylococcus aureus/fisiologia , Staphylococcus aureus/efeitos dos fármacos , Vibrio cholerae/fisiologia , Escherichia coli/fisiologia , Escherichia coli/efeitos dos fármacos , Análise de Elementos Finitos , Membrana Celular/fisiologia , Membrana Celular/efeitos dos fármacos , Parede Celular/efeitos dos fármacos
4.
PLoS Genet ; 20(4): e1011234, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598601

RESUMO

Peptidoglycan (PG) is the main component of the bacterial cell wall; it maintains cell shape while protecting the cell from internal osmotic pressure and external environmental challenges. PG synthesis is essential for bacterial growth and survival, and a series of PG modifications are required to allow expansion of the sacculus. Endopeptidases (EPs), for example, cleave the crosslinks between adjacent PG strands to allow the incorporation of newly synthesized PG. EPs are collectively essential for bacterial growth and must likely be carefully regulated to prevent sacculus degradation and cell death. However, EP regulation mechanisms are poorly understood. Here, we used TnSeq to uncover novel EP regulators in Vibrio cholerae. This screen revealed that the carboxypeptidase DacA1 (PBP5) alleviates EP toxicity. dacA1 is essential for viability on LB medium, and this essentiality was suppressed by EP overexpression, revealing that EP toxicity both mitigates, and is mitigated by, a defect in dacA1. A subsequent suppressor screen to restore viability of ΔdacA1 in LB medium identified hypomorphic mutants in the PG synthesis pathway, as well as mutations that promote EP activation. Our data thus reveal a more complex role of DacA1 in maintaining PG homeostasis than previously assumed.


Assuntos
Carboxipeptidases , Parede Celular , Endopeptidases , Peptidoglicano , Vibrio cholerae , Peptidoglicano/metabolismo , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Endopeptidases/genética , Endopeptidases/metabolismo , Carboxipeptidases/genética , Carboxipeptidases/metabolismo , Parede Celular/metabolismo , Parede Celular/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Epistasia Genética , Mutação
5.
Nat Commun ; 15(1): 3105, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600130

RESUMO

Disordered protein sequences can exhibit different binding modes, ranging from well-ordered folding-upon-binding to highly dynamic fuzzy binding. The primary function of the intrinsically disordered region of the antitoxin HigA2 from Vibrio cholerae is to neutralize HigB2 toxin through ultra-high-affinity folding-upon-binding interaction. Here, we show that the same intrinsically disordered region can also mediate fuzzy interactions with its operator DNA and, through interplay with the folded helix-turn-helix domain, regulates transcription from the higBA2 operon. NMR, SAXS, ITC and in vivo experiments converge towards a consistent picture where a specific set of residues in the intrinsically disordered region mediate electrostatic and hydrophobic interactions while "hovering" over the DNA operator. Sensitivity of the intrinsically disordered region to scrambling the sequence, position-specific contacts and absence of redundant, multivalent interactions, point towards a more specific type of fuzzy binding. Our work demonstrates how a bacterial regulator achieves dual functionality by utilizing two distinct interaction modes within the same disordered sequence.


Assuntos
Proteínas Intrinsicamente Desordenadas , Vibrio cholerae , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Vibrio cholerae/metabolismo , Espalhamento a Baixo Ângulo , Ligação Proteica , Difração de Raios X , DNA/metabolismo , Proteínas Intrinsicamente Desordenadas/metabolismo
6.
Swiss Med Wkly ; 154: 3437, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38579327

RESUMO

STUDY AIMS: Although non-toxigenic Vibrio cholerae lack the ctxAB genes encoding cholera toxin, they can cause diarrhoeal disease and outbreaks in humans. In Switzerland, V. cholerae is a notifiable pathogen and all clinical isolates are analysed at the National Reference Laboratory for Enteropathogenic Bacteria and Listeria. Up to 20 infections are reported annually. In this study, we investigated the population structure and genetic characteristics of non-toxigenic V. cholerae isolates collected over five years. METHODS:  V. cholerae isolates were serotyped and non-toxigenic isolates identified using a ctxA-specific PCR. Following Illumina whole-genome sequencing, genome assemblies were screened for virulence and antibiotic resistance genes. Phylogenetic analyses were performed in the context of 965 publicly available V. cholerae genomes. RESULTS: Out of 33 V. cholerae infections reported between January 2017 and January 2022 in Switzerland, 31 were caused by ctxA-negative isolates. These non-toxigenic isolates originated from gastrointestinal (n = 29) or extraintestinal (n = 2) sites. They were phylogenetically diverse and belonged to 29 distinct sequence types. Two isolates were allocated to the lineage L3b, a ctxAB-negative but tcpA-positive clade previously associated with regional outbreaks. The remaining 29 isolates were placed in lineage L4, which is associated with environmental strains. Genes or mutations associated with reduced susceptibility to the first-line antibiotics fluoroquinolones and tetracyclines were identified in 11 and 3 isolates, respectively. One isolate was predicted to be multidrug resistant. CONCLUSIONS:  V. cholerae infections in Switzerland are rare and predominantly caused by lowly virulent ctxAB-negative and tcpA-negative strains. As V. cholerae is not endemic in Switzerland, cases are assumed to be acquired predominantly during travel. This assumption was supported by the phylogenetic diversity of the analysed isolates.


Assuntos
Cólera , Vibrio cholerae , Humanos , Vibrio cholerae/genética , Cólera/epidemiologia , Cólera/microbiologia , Estudos Transversais , Filogenia , Suíça/epidemiologia , Genômica
7.
Science ; 384(6693): eadj3166, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38669570

RESUMO

Despite an increasingly detailed picture of the molecular mechanisms of bacteriophage (phage)-bacterial interactions, we lack an understanding of how these interactions evolve and impact disease within patients. In this work, we report a year-long, nationwide study of diarrheal disease patients in Bangladesh. Among cholera patients, we quantified Vibrio cholerae (prey) and its virulent phages (predators) using metagenomics and quantitative polymerase chain reaction while accounting for antibiotic exposure using quantitative mass spectrometry. Virulent phage (ICP1) and antibiotics suppressed V. cholerae to varying degrees and were inversely associated with severe dehydration depending on resistance mechanisms. In the absence of antiphage defenses, predation was "effective," with a high predator:prey ratio that correlated with increased genetic diversity among the prey. In the presence of antiphage defenses, predation was "ineffective," with a lower predator:prey ratio that correlated with increased genetic diversity among the predators. Phage-bacteria coevolution within patients should therefore be considered in the deployment of phage-based therapies and diagnostics.


Assuntos
Bacteriófagos , Cólera , Variação Genética , Vibrio cholerae , Cólera/microbiologia , Vibrio cholerae/genética , Vibrio cholerae/virologia , Bacteriófagos/genética , Bacteriófagos/fisiologia , Humanos , Bangladesh , Antibacterianos/uso terapêutico , Índice de Gravidade de Doença , Adulto , Metagenômica
8.
Arch Microbiol ; 206(5): 224, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642319

RESUMO

BACKGROUND: Vibrio cholerae can endure harsh environmental conditions by transitioning into viable but non-culturable (VBNC) form and resuscitate upon return of appropriate conditions. METHOD: In this study, we assessed the impact of physicochemical and microbiological factors, on the development of low temperature-induced VBNC state and subsequent recovery by temperature upshift. RESULTS: In estuarine water, Vibrio cholerae exhibits a slower decline in culturability over a period of 77 days as compared to 10 days in fresh water. When variable cell numbers from different growth phases were used for VBNC induction, it was observed that the higher inoculum size (106-107 cfu ml-1) from the late log phase culture appears to be crucial for entering the VBNC state. Conversely, starved cells could enter the VBNC state with an initial inoculum of 104-105 cfu ml-1, followed by resuscitation as well. The addition of glucose, GlcNAc and mannitol differentially affects progression into VBNC, while the addition of tryptone, yeast extract and casamino acid facilitated early entry into the VBNC state and shortened the length of the recovery period. CONCLUSION: Altogether these findings demonstrated that the ionic strength of water, inoculum size and the availability of nutrients played distinct roles during VBNC induction and resuscitation.


Assuntos
Vibrio cholerae , Temperatura , Temperatura Baixa , Aminoácidos , Água , Viabilidade Microbiana
9.
Cell Host Microbe ; 32(5): 727-738.e6, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38579715

RESUMO

Many, if not all, bacteria use quorum sensing (QS) to control collective behaviors, and more recently, QS has also been discovered in bacteriophages (phages). Phages can produce communication molecules of their own, or "listen in" on the host's communication processes, to switch between lytic and lysogenic modes of infection. Here, we study the interaction of Vibrio cholerae with the lysogenic phage VP882, which is activated by the QS molecule DPO. We discover that induction of VP882 results in the binding of phage transcripts to the major RNA chaperone Hfq, which in turn outcompetes and downregulates host-encoded small RNAs (sRNAs). VP882 itself also encodes Hfq-binding sRNAs, and we demonstrate that one of these sRNAs, named VpdS, promotes phage replication by regulating host and phage mRNA levels. We further show that host-encoded sRNAs can antagonize phage replication by downregulating phage mRNA expression and thus might be part of the host's phage defense arsenal.


Assuntos
Bacteriófagos , Fator Proteico 1 do Hospedeiro , Percepção de Quorum , Vibrio cholerae , Vibrio cholerae/virologia , Vibrio cholerae/genética , Percepção de Quorum/genética , Bacteriófagos/genética , Bacteriófagos/fisiologia , Fator Proteico 1 do Hospedeiro/metabolismo , Fator Proteico 1 do Hospedeiro/genética , Replicação Viral , Lisogenia , RNA Viral/genética , RNA Viral/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , Regulação Bacteriana da Expressão Gênica , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Interações entre Hospedeiro e Microrganismos/genética
10.
Nucleic Acids Res ; 52(6): 2761-2775, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38471818

RESUMO

CRISPR-Cas provides adaptive immunity in prokaryotes. Type III CRISPR systems detect invading RNA and activate the catalytic Cas10 subunit, which generates a range of nucleotide second messengers to signal infection. These molecules bind and activate a diverse range of effector proteins that provide immunity by degrading viral components and/or by disturbing key aspects of cellular metabolism to slow down viral replication. Here, we focus on the uncharacterised effector Csx23, which is widespread in Vibrio cholerae. Csx23 provides immunity against plasmids and phage when expressed in Escherichia coli along with its cognate type III CRISPR system. The Csx23 protein localises in the membrane using an N-terminal transmembrane α-helical domain and has a cytoplasmic C-terminal domain that binds cyclic tetra-adenylate (cA4), activating its defence function. Structural studies reveal a tetrameric structure with a novel fold that binds cA4 specifically. Using pulse EPR, we demonstrate that cA4 binding to the cytoplasmic domain of Csx23 results in a major perturbation of the transmembrane domain, consistent with the opening of a pore and/or disruption of membrane integrity. This work reveals a new class of cyclic nucleotide binding protein and provides key mechanistic detail on a membrane-associated CRISPR effector.


Many anti-viral defence systems generate a cyclic nucleotide signal that activates cellular defences in response to infection. Type III CRISPR systems use a specialised polymerase to make cyclic oligoadenylate (cOA) molecules from ATP. These can bind and activate a range of effector proteins that slow down viral replication. In this study, we focussed on the Csx23 effector from the human pathogen Vibrio cholerae ­ a trans-membrane protein that binds a cOA molecule, leading to anti-viral immunity. Structural studies revealed a new class of nucleotide recognition domain, where cOA binding is transmitted to changes in the trans-membrane domain, most likely resulting in membrane depolarisation. This study highlights the diversity of mechanisms for anti-viral defence via nucleotide signalling.


Assuntos
Proteínas de Bactérias , Proteínas Associadas a CRISPR , Vibrio cholerae , Nucleotídeos de Adenina/metabolismo , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Nucleotídeos Cíclicos , Sistemas do Segundo Mensageiro , Proteínas de Bactérias/metabolismo , Vibrio cholerae/metabolismo
11.
Infect Genet Evol ; 120: 105587, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38518953

RESUMO

Non-O1/non-O139 Vibrio cholerae (NOVC) are ubiquitous in aquatic ecosystems. In rare cases, they can cause intestinal and extra-intestinal infections in human. This ability is associated with various virulence factors. The presence of NOVC in German North Sea and Baltic Sea was observed in previous studies. However, data on virulence characteristics are still scarce. Therefore, this work aimed to investigating the virulence potential of NOVC isolated in these two regions. In total, 31 NOVC strains were collected and subjected to whole genome sequencing. In silico analysis of the pathogenic potential was performed based on the detection of genes involved in colonization and virulence. Phenotypic assays, including biofilm formation, mobility and human serum resistance assays were applied for validation. Associated toxin genes (hlyA, rtxA, chxA and stn), pathogenicity islands (Vibrio pathogenicity island 2 (VPI-II) and Vibrio seventh pathogenicity island 2 (VSP-II)) and secretion systems (Type II, III and VI secretion system) were observed. A maximum likelihood analysis from shared core genes revealed a close relationship between clinical NOVCs published in NCBI and environmental strains from this study. NOVC strains are more mobile at 37 °C than at 25 °C, and 68% of the NOVC strains could form strong biofilms at both temperatures. All tested strains were able to lyse erythrocytes from both human and sheep blood. Additionally, one strain could survive up to 60% and seven strains up to 40% human serum at 37 °C. Overall, the genetic virulence profile as well as the phenotypic virulence characteristics of the investigated NOVC from the German North Sea and Baltic Sea suggest potential human pathogenicity.


Assuntos
Vibrio cholerae não O1 , Fatores de Virulência , Fatores de Virulência/genética , Humanos , Virulência/genética , Vibrio cholerae não O1/genética , Vibrio cholerae não O1/patogenicidade , Vibrio cholerae não O1/isolamento & purificação , Alemanha , Ilhas Genômicas/genética , Biofilmes/crescimento & desenvolvimento , Filogenia , Mar do Norte , Vibrio cholerae/genética , Vibrio cholerae/patogenicidade , Vibrio cholerae/classificação , Cólera/microbiologia , Animais , Sequenciamento Completo do Genoma
12.
Nat Commun ; 15(1): 2018, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38443393

RESUMO

Matrix-encapsulated communities of bacteria, called biofilms, are ubiquitous in the environment and are notoriously difficult to eliminate in clinical and industrial settings. Biofilm formation likely evolved as a mechanism to protect resident cells from environmental challenges, yet how bacteria undergo threat assessment to inform biofilm development remains unclear. Here we find that population-level cell lysis events induce the formation of biofilms by surviving Vibrio cholerae cells. Survivors detect threats by sensing a cellular component released through cell lysis, which we identify as norspermidine. Lysis sensing occurs via the MbaA receptor with genus-level specificity, and responsive biofilm cells are shielded from phage infection and attacks from other bacteria. Thus, our work uncovers a connection between bacterial lysis and biofilm formation that may be broadly conserved among microorganisms.


Assuntos
Bacteriófagos , Vibrio cholerae , Biofilmes , Agregação Celular , Morte Celular
13.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38486350

RESUMO

AIMS: Although elasmobranchs are consumed worldwide, bacteriological assessments for this group are still sorely lacking. In this context, this study assessed bacteria of sharks and rays from one of the most important landing ports along the Rio de Janeiro coast. METHODS AND RESULTS: Bacteria were isolated from the cloacal swabs of the sampled elasmobranchs. They were cultured, and Vibrio, Aeromonas, and Enterobacterales were isolated and identified. The isolated bacteria were then biochemically identified and antimicrobial susceptibility assays were performed. Antigenic characterizations were performed for Salmonella spp. and Polymerase Chain Reaction (PCR) assays were performed to identify Escherichia coli pathotypes. Several bacteria of interest in the One Health context were detected. The most prevalent Enterobacterales were Morganella morganii and Citrobacter freundii, while Vibrio harveyi and Vibrio fluvialis were the most prevalent among Vibrio spp. and Aeromonas allosacharophila and Aeromonas veronii bv. veronii were the most frequent among Aeromonas spp. Several bacteria also displayed antimicrobial resistance, indicative of Public Health concerns. A total of 10% of Vibrio strains were resistant to trimethoprim-sulfamethoxazole and 40% displayed intermediate resistance to cefoxitin. Salmonella enterica strains displayed intermediate resistance to ciprofloxacin, nalidixic acid and streptomycin. All V. cholerae strains were identified as non-O1/non-O139. The detected E. coli strains did not exhibit pathogenicity genes. This is the first study to perform serology assessments for S. enterica subsp. enterica isolated from elasmobranchs, identifying the zoonotic Typhimurium serovar. Salmonella serology evaluations are, therefore, paramount to identify the importance of elasmobranchs in the epidemiological salmonellosis chain. CONCLUSIONS: The detection of several pathogenic and antibiotic-resistant bacteria may pose significant Public Health risks in Brazil, due to high elasmobranch consumption rates, indicating the urgent need for further bacteriological assessments in this group.


Assuntos
Aeromonas , Tubarões , Vibrio cholerae , Animais , Escherichia coli , Brasil , Salmonella/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Aeromonas/genética
14.
Mol Biol Rep ; 51(1): 409, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461219

RESUMO

BACKGROUND: This is a unique and novel study delineating the genotyping and subsequent prediction of AMR determinants of Vibrio cholerae revealing the potential of contemporary strains to serve as precursors of severe AMR crisis in cholera. METHODS AND RESULTS: Genotyping of representative strains, VC1 and VC2 was undertaken to characterize antimicrobial resistance genes (ARGs) against chloramphenicol, SXT, nalidixic acid and streptomycin against which they were found to be resistant by antibiogram analysis in our previous investigation. strAB, sxt, sul2, qace∆1-sul1 were detected by PCR. Genome annotation and identification of ARGs with WGS helped to detect the presence of almG, varG, strA (APH(3'')-Ib), strB (APH(6)-Id), sul2, catB9, floR, CRP, dfrA1 genes. Signatures of resistance determinants and protein domains involved in antimicrobial resistance, primarily, efflux of antibiotics were identified on the basis of 30-100% homology to reference proteins. These domains were predicted to be involved in other metabolic functions on the basis of 100% identity with 100% coverage with reference protein and nucleotide sequences and were predicted to be of a diverse taxonomic origin accentuating the influence of the microbiota on AMR acquisition. Sequence analysis of QRDR (quinolone resistance-determining region) revealed SNPs. Cytoscape v3.8.2 was employed to analyse protein-protein interaction of MDR proteins, MdtA and EmrD-2, with nodes of vital AMR pathways. Vital nodes involved in efflux of different classes of antibiotics were found to be absent in VC1 and VC2 justifying the sensitivity of these strains to most antibiotics. CONCLUSIONS: The study helped to examine the resistome of VC isolated from recent outbreaks to understand the underlying reason of sensitivity to most antibiotics and also to characterize the ARGs in their genome. It revealed that VC is a reservoir of signatures of resistance determinants and serving as precursors for severe AMR crisis in cholera. This is the first study, to our knowledge, which has scrutinized and presented systematically, information on prospective domains which bear the potential of serving as AMR determinants in VC with the help of bioinformatic tools. This pioneering approach may help in the prediction of AMR landfalls and benefit epidemiological surveillance and early warning systems.


Assuntos
Cólera , Vibrio cholerae , Humanos , Vibrio cholerae/genética , Cólera/tratamento farmacológico , Cólera/epidemiologia , Antibacterianos/farmacologia , Estudos Prospectivos , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana
15.
J Appl Microbiol ; 135(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38449342

RESUMO

Cholera, caused by Vibrio cholerae, is a severe diarrheal disease that necessitates prompt diagnosis and effective treatment. This review comprehensively examines various diagnostic methods, from traditional microscopy and culture to advanced nucleic acid testing like polymerase spiral reaction and rapid diagnostic tests, highlighting their advantages and limitations. Additionally, we explore evolving treatment strategies, with a focus on the challenges posed by antibiotic resistance due to the activation of the SOS response pathway in V. cholerae. We discuss promising alternative treatments, including low-pressure plasma sterilization, bacteriophages, and selenium nanoparticles. The paper emphasizes the importance of multidisciplinary approaches combining novel diagnostics and treatments in managing and preventing cholera, a persistent global health challenge. The current re-emergent 7th pandemic of cholera commenced in 1961 and shows no signs of abeyance. This is probably due to the changing genetic profile of V. cholerae concerning bacterial pathogenic toxins. Given this factor, we argue that the disease is effectively re-emergent, particularly in Eastern Mediterranean countries such as Lebanon, Syria, etc. This review considers the history of the current pandemic, the genetics of the causal agent, and current treatment regimes. In conclusion, cholera remains a significant global health challenge that requires prompt diagnosis and effective treatment. Understanding the history, genetics, and current treatments is crucial in effectively addressing this persistent and re-emergent disease.


Assuntos
Bacteriófagos , Cólera , Vibrio cholerae , Humanos , Cólera/diagnóstico , Cólera/epidemiologia , Cólera/prevenção & controle , Vibrio cholerae/genética , Bacteriófagos/fisiologia , Filogenia , Toxina da Cólera/genética , Toxina da Cólera/metabolismo
16.
Genome Biol Evol ; 16(3)2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38366392

RESUMO

The evolutionary relationship between the biofilm lifestyle and antibiotic resistance enzymes remains a subject of limited understanding. Here, we investigate how ß-lactamases affect biofilm formation in Vibrio cholerae and how selection for a biofilm lifestyle impacts the evolution of these enzymes. Genetically diverse ß-lactamases expressed in V. cholerae displayed a strong inhibitory effect on biofilm production. To understand how natural evolution affects this antagonistic pleiotropy, we randomly mutagenized a ß-lactamase and selected for elevated biofilm formation. Our results revealed that biofilm evolution selects for ß-lactamase variants able to hydrolyze ß-lactams without inhibiting biofilms. Mutational analysis of evolved variants demonstrated that restoration of biofilm development was achieved either independently of enzymatic function or by actively leveraging enzymatic activity. Taken together, the biofilm lifestyle can impose a profound selective pressure on antimicrobial resistance enzymes. Shedding light on such evolutionary interplays is of importance to understand the factors driving antimicrobial resistance.


Assuntos
Anti-Infecciosos , Vibrio cholerae , beta-Lactamases/genética , Biofilmes , Vibrio cholerae/genética , beta-Lactamas/farmacologia , Anti-Infecciosos/farmacologia
17.
Mol Microbiol ; 121(5): 850-864, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38323722

RESUMO

The diarrheal disease cholera is caused by the versatile and responsive bacterium Vibrio cholerae, which is capable of adapting to environmental changes. Among others, the alternative sigma factor RpoS activates response pathways, including regulation of motility- and chemotaxis-related genes under nutrient-poor conditions in V. cholerae. Although RpoS has been well characterised, links between RpoS and other regulatory networks remain unclear. In this study, we identified the ArcAB two-component system to control rpoS transcription and RpoS protein stability in V. cholerae. In a manner similar to that seen in Escherichia coli, the ArcB kinase not only activates the response regulator ArcA but also RssB, the anti-sigma factor of RpoS. Our results demonstrated that, in V. cholerae, RssB is phosphorylated by ArcB, which subsequently activates RpoS proteolysis. Furthermore, ArcA acts as a repressor of rpoS transcription. Additionally, we determined that the cysteine residue at position 180 of ArcB is crucial for signal recognition and activity. Thus, our findings provide evidence linking RpoS response to the anoxic redox control system ArcAB in V. cholerae.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Fator sigma , Vibrio cholerae , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Fator sigma/metabolismo , Fator sigma/genética , Fosforilação , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Quimiotaxia/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Redes Reguladoras de Genes
18.
J Org Chem ; 89(6): 4019-4030, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38403962

RESUMO

Vibrio cholerae is a pathogen responsible for the deadly pandemic - cholera. The glycans present on the surface of various strains of V. cholerae are considered as potential vaccine candidates. The tetrasaccharide repeating unit (RU) of V. cholerae O43 is decorated with less-explored rare deoxy amino sugars like d-quinosamine and d-viosamine, along with a rare amino acid, N-acetyl-l-allothreonine. Herein, we report a detailed account of the total synthesis of V. cholerae O43 tetrasaccharide RU. In our earlier attempt, while a one-pot assembly of trisaccharide was successful, the final coupling with a fully functionalized d-viosamine donor was low yielding. The successful route involved employing the Fmoc-protected d-viosamine building block as a donor and a late-stage amide bond formation of the tetrasaccharide.


Assuntos
Cólera , Vibrio cholerae , Humanos , Vibrio cholerae/química , Oligossacarídeos/química , Trissacarídeos
19.
Cell Rep ; 43(2): 113750, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38340318

RESUMO

To maintain an effective barrier, intestinal progenitor cells must divide at a rate that matches the loss of dead and dying cells. Otherwise, epithelial breaches expose the host to systemic infection by gut-resident microbes. Unlike most pathogens, Vibrio cholerae blocks tissue repair by arresting progenitor proliferation in the Drosophila model. At present, we do not understand how V. cholerae circumvents such a critical antibacterial defense. We find that V. cholerae blocks epithelial repair by activating the growth inhibitor bone morphogenetic protein (BMP) pathway in progenitors. Specifically, we show that interactions between V. cholerae and gut commensals initiate BMP signaling via host innate immune defenses. Notably, we find that V. cholerae also activates BMP and arrests proliferation in zebrafish intestines, indicating an evolutionarily conserved link between infection and failure in tissue repair. Our study highlights how enteric pathogens engage host immune and growth regulatory pathways to disrupt intestinal epithelial repair.


Assuntos
Vibrio cholerae , Peixe-Zebra , Animais , Antibacterianos , Proteínas Morfogenéticas Ósseas , Drosophila , Proliferação de Células
20.
BMC Genom Data ; 25(1): 18, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360573

RESUMO

OBJECTIVE: Vibrio cholerae is an enteric pathogen that poses a significant threat to global health. It causes severe dehydrating diarrheal disease cholera in humans. V. cholerae could be acquired either from consuming contaminated seafood or direct contact with polluted waters. As part of a larger program that assesses the microbial community profile in aquatic systems, V. cholerae strain NB-183 was isolated and characterized using a combination of culture- and whole-genome sequencing-based approaches. DATA DESCRIPTION: Here we report the assembled and annotated whole-genome sequence of a V. cholerae strain NB-183 isolated from a recreational freshwater lake in Ontario, Canada. The genome was sequenced using short-read Illumina systems. The whole-genome sequencing yielded 4,112,549 bp genome size with 99 contigs with an average genome coverage of 96× and 47.42% G + C content. The whole genome-based comparison, phylogenomic and gene repertoire indicates that this strain harbors multiple virulence genes and biosynthetic gene clusters. This genome sequence and its associated datasets provided in this study will be an indispensable resource to enhance the understanding of the functional, ecological, and evolutionary dynamics of V. cholerae.


Assuntos
Cólera , Vibrio cholerae , Humanos , Vibrio cholerae/genética , Ontário , Virulência/genética , Água Doce
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA