IWASHITA Hanako
   Department   School of Medicine, School of Medicine
   Position   Assistant Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Comparative analyses of CTX prophage region of Vibrio cholerae seventh pandemic wave 1 strains isolated in Asia.
Journal Formal name:Microbiology and immunology
Abbreviation:Microbiol Immunol
ISSN code:13480421/03855600
Domestic / ForeginForegin
Volume, Issue, Page 62(10),pp.635-650
Author and coauthor PhamTho Duc, NguyenTuan Hai, IwashitaHanako, TakemuraTaichiro, MoritaKouichi, YamashiroTetsu
Publication date 2018/10
Summary Vibrio cholerae O1 causes cholera, and cholera toxin, the principal mediator of massive diarrhea, is encoded by ctxAB in the cholera toxin (CTX) prophage. In this study, the structures of the CTX prophage region of V. cholerae strains isolated during the seventh pandemic wave 1 in Asian countries were determined and compared. Eighteen strains were categorized into eight groups by CTX prophage region-specific restriction fragment length polymorphism and PCR profiles and the structure of the region of a representative strain from each group was determined by DNA sequencing. Eight representative strains revealed eight distinct CTX prophage regions with various combinations of CTX-1, RS1 and a novel genomic island on chromosome I. CTX prophage regions carried by the wave 1 strains were diverse in structure. V. cholerae strains with an area specific CTX prophage region are believed to circulate in South-East Asian countries; additionally, multiple strains with distinct types of CTX prophage region are co-circulating in the area. Analysis of a phylogenetic tree generated by single nucleotide polymorphism differences across 2483 core genes revealed that V. cholerae strains categorized in the same group based on CTX prophage region structure were segregated in closer clusters. CTX prophage region-specific recombination events or gain and loss of genomic elements within the region may have occurred at much higher frequencies and contributed to producing a panel of CTX prophage regions with distinct structures among V. cholerae pathogenic strains in lineages with close genetic backgrounds in the early wave 1 period of the seventh cholera pandemic.
DOI 10.1111/1348-0421.12648
PMID 30211956