title: Replication ofVibrio choleraeclassical CTX phage.
abstract: The toxigenic classical and El Tor biotypeVibrio choleraeserogroup O1 strains are generated by lysogenization of host-type-specific cholera toxin phages (CTX phages). Experimental evidence of the replication and transmission of an El Tor biotype-specific CTX phage, CTX-1, has explained the evolution ofV. choleraeEl Tor biotype strains. The generation of classical biotype strains has not been demonstrated in the laboratory, and the classical biotype-specific CTX phage, CTX-cla, is considered to be defective with regard to replication. However, the identification of atypical El Tor strains that contain CTX-cla-like phage, CTX-2, indicates that CTX-cla and CTX-2 replicate and can be transmitted toV. choleraestrains. The replication of CTX-cla and CTX-2 phages and the transduction of El Tor biotype strains by various CTX phages under laboratory conditions are demonstrated in this report. We have established a plasmid-based CTX phage replication system that supports the replication of CTX-1, CTX-cla, CTX-2, and CTX-O139. The replication of CTX-2 from the tandem repeat of lysogenic CTX-2 in Wave 2 El Tor strains is also presented. El Tor biotype strains can be transduced by CTX phages in vitro by introducing a point mutation intoxT, the transcriptional activator of thetcp(toxin coregulated pilus) gene cluster and the cholera toxin gene. This mutation also increases the expression of cholera toxin in El Tor strains in a sample single-phase culture. Our results thus constitute experimental evidence of the genetic mechanism of the evolution ofV. cholerae.
authors.affiliation: Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan 15588, Republic of Korea.|Institute of Pharmacological Research, Hanyang University, Ansan 15588, Republic of Korea.
authors.forename: Eun Jin
authors.initials: EJ
authors.lastname: Kim
authors.affiliation: Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan 15588, Republic of Korea.|Institute of Pharmacological Research, Hanyang University, Ansan 15588, Republic of Korea.
authors.forename: Hyun Jin
authors.initials: HJ
authors.lastname: Yu
authors.affiliation: Chunlab, Inc., Seoul National University, Seoul 08826, Republic of Korea.
authors.forename: Je Hee
authors.initials: JH
authors.lastname: Lee
authors.affiliation: International Vaccine Institute, Seoul 08826, Republic of Korea.
authors.forename: Jae-Ouk
authors.initials: JO
authors.lastname: Kim
authors.affiliation: Department of Oral Microbiology and Immunology, Seoul National University, Seoul 08826, Republic of Korea.
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Han
authors.affiliation: Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea.
authors.forename: Cheol-Heui
authors.initials: CH
authors.lastname: Yun
authors.affiliation: School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea.
authors.forename: Jongsik
authors.initials: J
authors.lastname: Chun
authors.affiliation: South East Asia Regional Office, World Health Organization, New Delhi 110002, India nairg@who.int dongwook@hanyang.ac.kr.
authors.forename: G Balakrish
authors.initials: GB
authors.lastname: Nair
authors.affiliation: Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan 15588, Republic of Korea; nairg@who.int dongwook@hanyang.ac.kr.|Institute of Pharmacological Research, Hanyang University, Ansan 15588, Republic of Korea.
authors.forename: Dong Wook
authors.initials: DW
authors.lastname: Kim
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001435:Bacteriophages / Q000235:genetics / Q000378:metabolism; D002772:Cholera Toxin / Q000096:biosynthesis / Q000235:genetics; D002876:Chromosomes, Bacterial / Q000737:chemistry / Q000378:metabolism / Q000821:virology; D015870:Gene Expression; D014644:Genetic Variation; D016679:Genome, Viral; D008242:Lysogeny; D009154:Mutation; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D039002:Prophages / Q000235:genetics* / Q000378:metabolism; D020080:Tandem Repeat Sequences; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014161:Transduction, Genetic; D041241:Vibrio cholerae O1 / Q000235:genetics / Q000821:virology; D014779:Virus Replication
chemical_list: D001426:Bacterial Proteins; D014157:Transcription Factors; C075626:tcpN protein, Vibrio cholerae; D002772:Cholera Toxin
keywords: CTX phage; Vibrio cholerae; biotype; cholera toxin