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Updated: Jun 12, 2025
07:58
Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
Published on: May 30, 2017
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Allelic variations and gene cluster modularity act as nonlinear bottlenecks for cholera emergence
Mario López-Pérez1,2, Deepak Balasubramanian1,3, Alicia Campos-Lopez1,2
1Burnett School of Biomedical Sciences, College of Medicine, University of Central, Florida, Orlando, FL, 32827.
Summary
Understanding how Vibrio cholerae strains become human pathogens is key. This study reveals that acquiring specific gene clusters and alleles is crucial for the pandemic cholera group (PCG) to colonize the human gut.
Area of Science:
- Microbiology
- Evolutionary Biology
- Genomics
Background:
- The emergence of specific bacterial strains as human pathogens is poorly understood.
- Cholera, caused by pandemic cholera group (PCG) strains of *Vibrio cholerae*, serves as a model to study this phenomenon.
Purpose of the Study:
- To investigate the ecoevolutionary dynamics and genetic factors driving the emergence of toxigenic *Vibrio cholerae*.
- To identify genetic determinants conferring a competitive advantage for intestinal colonization.
Main Methods:
- Comprehensive genomic analysis of over 1,840 *V. cholerae* genomes, including environmental isolates.
- Hierarchical classification of *V. cholerae* strains into eleven groups.
- Comparative analysis of gene clusters and allelic variations between pathogenic and environmental strains.
Main Results:
- The PCG is part of the largest *V. cholerae* group, sharing a lineage with environmental strains.
- Acquisition of unique gene clusters and specific allelic variations are critical for intestinal colonization.
- Certain PCG-associated alleles are essential for colonization, while others provide a nonlinear competitive advantage, acting as a bottleneck for PCG emergence.
- These key alleles do not influence colonization in environmental reservoirs.
Conclusions:
- The emergence of toxigenic *Vibrio cholerae* is driven by the acquisition of specific genetic elements that enhance intestinal colonization.
- Understanding these evolutionary roots provides a framework for studying pathogenic clone emergence in environmental bacterial populations.
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