Comparative sequence analysis of recA gene among Vibrio cholerae isolates from Iran with globally reported sequences
ABSTRACT To study the genetic relatedness between V. cholerae isolates from Iran and other countries based on housekeeping gene recA sequence analysis.
A 995-bp region of the recA gene from 24 V. cholerae isolates obtained from human and surface water origins in Iran over a 5-year period was sequenced and compared with the sequence data from the isolates belonging to other places. Cluster analysis of the constructed dendrogram based on recA sequence divergence for our clinical isolates showed one sequence type (ST), whereas environmental isolates revealed eight STs. Interestingly, one of our environmental isolates was intermixed with clinical isolates in the largest cluster containing the epidemic strains. Our 24 isolates plus 198 global isolates available in the GenBank showed 77 sequence types (STs) with at least one nucleotide difference.
Our result suggested that recA sequencing is a reliable analysis method for understanding the relatedness of the local isolates with the isolates obtained elsewhere.
Understanding the genetic relatedness between V. cholerae isolates could give insights into the health care system for better control and prevention of the cholera.
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ABSTRACT: Cholera toxin is the most important virulence factor of epidemic Vibrio cholerae strains. It is encoded by ctxAB operon that is a part of the genome of a filamentous bacteriophage (CTXphi). This bacteriophage plays an important role in the evolution and pathogenesis of V. cholerae and genetic variations that occur within the genome of this bacteriophage affect V. cholerae toxicity and potential to cause epidemics and can be used as a powerful tool in epidemiological investigations.Reviews in Medical Microbiology 01/2014; DOI:10.1097/MRM.0000000000000017 · 0.52 Impact Factor
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ABSTRACT: Vibrio cholera, a gram-negative bacterium, has been categorised into clinical and environmental species. Phylogenetic studies have been performed to investigate the relationships of the V. cholerae populations in worldwide. In this study, phylogenetic relationship between V. cholerae isolates from Iran and other regions of the world was determined, based on three housekeeping genes analysis. Results for Iranian strains showed that congruency of asd and hlyA phylogenetic trees were remarkably higher than recA tree. Iranian strains displayed 2-3%, 1-14% and 3-5% deference in asd, hlyA and recA nucleotide sequences, respectively. Sequence similarity degrees were variable between Iranian and other region's strains. Furthermore, the non-congruence in the phylogeny of the pathogenic clones in cladograms is probably due to horizontal gene transfer. Finally, results of this study suggest that monitoring of surface waters for housekeeping genes of V. cholerae in the cholera endemic areas may be valuable for forecasting the expected cholera outbreaks.International Journal of Computational Biology and Drug Design 01/2015; 8(1). DOI:10.1504/IJCBDD.2015.068789
Dataset: hajia 2014 cholera