Recent Vibrio cholerae O1 Epidemic Strains Are Unable To Replicate CTXΦ Prophage Genome
Kaoru Ochi, Tamaki Mizuno, Prosenjit Samanta, Asish K. Mukhopadhyay, Shin-ichi Miyoshi, Daisuke Imamura
Abstract
Cholera is an acute diarrheal disease caused by pathogenic strains of V. cholerae generated by lysogenization of the filamentous cholera toxin phage CTXΦ. The analysis revealed that recent isolates possessed altered CTXΦ prophage array of prototype El Tor strain and were defective in replicating the CTXΦ genome. Classification of CTXΦ structures in isolated years suggested that V. cholerae epidemic strains became capable of producing CTXΦ phage particles since the 1970s. However, V. cholerae epidemic strains again lost the capacity for CTXΦ production around the year 2010, suggesting that a critical change had occurred in the dissemination pattern of the current cholera pandemic.