scholarly journals The Amazonia Variant of Vibrio cholerae: Molecular Identification and Study of Virulence Genes

1998 ◽  
Vol 93 (5) ◽  
pp. 601-607 ◽  
Author(s):  
MAS Baptista ◽  
JRC Andrade ◽  
ACP Vicente ◽  
CA Salles ◽  
A Coelho
Keyword(s):  
Vibrio Cholerae ◽  
Molecular Identification ◽  
Virulence Genes

scholarly journals Correction: Engineering microbial physiology with synthetic polymers: cationic polymers induce biofilm formation inVibrio choleraeand downregulate the expression of virulence genes

2018 ◽  
Vol 9 (39) ◽  
pp. 7715-7715
Author(s):  
Nicolas Perez-Soto ◽  
Lauren Moule ◽  
Daniel N. Crisan ◽  
Ignacio Insua ◽  
Leanne M. Taylor-Smith ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Biofilm Formation ◽  
Virulence Genes ◽  
Synthetic Polymers ◽  
Cationic Polymers ◽  
Microbial Physiology

Correction for ‘Engineering microbial physiology with synthetic polymers: cationic polymers induce biofilm formation inVibrio choleraeand downregulate the expression of virulence genes’ by Nicolas Perez-Sotoet al.,Chem. Sci., 2017,8, 5291–5298.

scholarly journals Two cases of septic shock with different outcomes caused by non-O1/non-O139 Vibrio cholerae isolates

2020 ◽  
Vol 48 (6) ◽  
pp. 030006052093345
Author(s):  
Jie Chen ◽  
Jian Huang ◽  
Meirong Huang ◽  
Zehui Chen ◽  
Anlin Chen ◽  
...  
Keyword(s):  
Septic Shock ◽  
Vibrio Cholerae ◽  
High Mortality ◽  
Virulence Genes ◽  
Antibiotic Sensitivity ◽  
Sporadic Cases ◽  
Human Infections ◽  
Sequence Types

In recent decades, increasing numbers of human infections have been linked to non-O1/non-O139 Vibrio cholerae. Septicemia resulting from non-O1/non-O139 V. cholerae infection is rare but has high mortality. The pathogenesis of non-O1/non-O139 V. cholerae septicemia is poorly understood. Here, we report two sporadic cases of septicemia following non-O1/non-O139 V. cholerae infection from an inland area of China. Patient 1 died rapidly within 24 hours, while patient 2 gradually recovered from septic shock. To explore the reasons for these divergent outcomes, we compared the two cases, tested the antibiotic sensitivity of the two isolates, and investigated their virulence genes and sequence types.

scholarly journals A Vibrio cholerae LysR Homolog, AphB, Cooperates with AphA at the tcpPH Promoter To Activate Expression of the ToxR Virulence Cascade

1999 ◽  
Vol 181 (14) ◽  
pp. 4250-4256 ◽  
Author(s):  
Gabriela Kovacikova ◽  
Karen Skorupski
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Genes ◽  
Virulence Gene ◽  
Growth Conditions ◽  
Culture Conditions ◽  
Virulence Gene Expression ◽  
Environmental Stimuli ◽  
High Level ◽  
El Tor

ABSTRACT We describe here a new member of the LysR family of transcriptional regulators, AphB, which is required for activation of the Vibrio cholerae ToxR virulence cascade. AphB activates the transcription of the tcpPH operon in response to environmental stimuli, and this process requires cooperation with a second protein, AphA. The expression of neither aphA or aphB is strongly regulated by environmental stimuli, raising the possibility that the activities of the proteins themselves may be influenced under various conditions. Strains of the El Tor biotype of V. choleraetypically exhibit lower expression of ToxR-regulated virulence genes in vitro than classical strains and require specialized culture conditions (AKI medium) to induce high-level expression. We show here that expression of aphB from the tac promoter in El Tor biotype strains dramatically increases virulence gene expression to levels similar to those observed in classical strains under all growth conditions examined. These results suggest that AphB plays a role in the differential regulation of virulence genes between the two disease-causing biotypes.

scholarly journals Molecular characterization of Vibrio cholerae O1 strains circulating in Assam: a north eastern state of India

2021 ◽  
Author(s):  
Ajanta Sharma ◽  
Bornali Sarmah Dutta ◽  
Debajit Rabha ◽  
Elmy Samsun Rasul ◽  
Naba Kumar Hazarika
Keyword(s):  
Antibiotic Resistance ◽  
Vibrio Cholerae ◽  
Virulence Genes ◽  
Multiple Drug Resistance ◽  
Public Health Problem ◽  
Amino Acid Sequences ◽  
Multiple Drug ◽  
Major Public Health Problem ◽  
Genotype 3 ◽  
El Tor

Background and Objectives: Information on the genetic epidemiology of cholera in Assam, a northeastern state of India is lacking despite cholera being a major public health problem. The study aimed to determine the virulence genes and genes encoding antibiotic resistance in Vibrio cholerae isolates and to determine the prevalent genotypes based on the presence or absence of the virulence genes and ctxB genotype. Materials and Methods: Twenty-five V. cholerae strains were subjected to conventional biotyping and serotyping followed by multiplex PCR to detect ctxA, ctxB, zot, ace, O1rfb, tcpA, ompU, ompW, rtxC, hly and toxR and antibiotic resistance genes. Cholera toxin B (ctxB) gene was amplified followed by sequencing. Results: All the V. cholerae O1 isolates were El Tor Ogawa and showed the presence of the core toxin region representing the genome of the filamentous bacteriophage CTXø. The complete cassette of virulence genes was seen in 48% of the isolates which was the predominant genotype. All the isolates possessed amino acid sequences identical to the El Tor ctxB subunit of genotype 3. sulII gene was detected in 68% of the isolates, dfrA1 in 88%, strB in 48% and SXT gene was detected in 36% of the isolates. Conclusion: Toxigenic V. cholerae O1 El Tor Ogawa strains of ctxB genotype 3 carrying a large pool of virulence genes are prevailing in Assam. Presence of a transmissible genetic element SXT in 36% of the strains is of major concern as it indicates the emergence of multiple drug resistance among the V. cholerae isolates.  

scholarly journals Origins of pandemic Vibrio cholerae from environmental gene pools

2016 ◽  
Author(s):  
B. Jesse Shapiro ◽  
Inès Levade ◽  
Gabriela Kovacikova ◽  
Ronald K. Taylor ◽  
Salvador Almagro-Moreno
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Mammalian Host ◽  
Comparative Genomic ◽  
Gene Pools ◽  
Host Colonization ◽  
Bacterial Populations ◽  
Genomic Features ◽  
Clinical Strains

AbstractSome microbes can transition from an environmental lifestyle to a pathogenic one1–3. This ecological switch typically occurs through the acquisition of horizontally acquired virulence genes4,5. However, the genomic features that must be present in a population prior to the acquisition of virulence genes and emergence of pathogenic clones remain unknown. We hypothesized that virulence adaptive polymorphisms (VAPs) circulate in environmental populations and are required for this transition. We developed a comparative genomic framework for identifying VAPs, using Vibrio cholerae as a model. We then characterized several environmental VAP alleles to show that, while some of them reduced the ability of clinical strains to colonize a mammalian host, other alleles conferred efficient host colonization. These results show that VAPs are present in environmental bacterial populations prior to the emergence of virulent clones. We propose a scenario in which VAPs circulate in the environment, they become selected and enriched under certain ecologicalconditions, and finally a genomic background containing several VAPs acquires virulence factors that allows for its emergence as a pathogenic clone.

Molecular identification and pathogenicity study of virulent Vibrio cholerae non O1/O139 serotype associated with mortality of farmed Labeo rohita (Hamilton, 1822), in India

Aquaculture ◽  
2022 ◽  
Vol 547 ◽  
pp. 737529
Author(s):  
Manoharmayum Shaya Devi ◽  
Prasenjit Paria ◽  
Vikash Kumar ◽  
Pranaya Kumar Parida ◽  
Praveen Maurye ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Molecular Identification ◽  
Labeo Rohita
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