title: [Surveillance program on and the distribution related to the virulence-associated genes of Vibrio cholerae in estuary of Pearl River].
abstract: OBJECTIVE
  To understand the distribution, molecular characteristics and virulence genes of the O1 and O139 Vibrio cholerae isolates from the Pearl River Estuary water.
  
  
  METHODS
  Vibrio cholerae isolates collected from the Pearl River estuary waters from January 2009 to December 2010, were tested by PCR for eight virulence-related genes, including cholera toxin (ctxA), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlyA), toxin-coregulated pilus (tcpA), outer membrane protein (ompU), and the regulatory protein genes (tcpI, toxR). Genetic relation was assessed by pulsed-field gel electrophoresis (PFGE) and the patterns were clustered by BioNumerics.
  
  
  RESULTS
  From 1152 aquatic samples, 69 isolates were identified, including 41 Inaba, 18 Ogawa and 10 O139. All the isolates showed ctxA negative, while the hlyA and toxR genes were positive in all the isolates. 34.15% (14/41) of the Inaba strains were hlyA(+) toxR(+) ompU(+) ace(+) zot(+) tcpI(+), while 66.67% (12/18) belonged to Ogawa strains and 70% (7/10) of the O139 strains were hlyA(+) toxR(+). Through PFGE analysis, the O1 isolates formed three clusters in this study. The patterns of O1 isolates differed widely, with the similarity as 72.8% - 100.0%, while the patterns of O139 isolates having the similarity of 69.9% - 95.5%.
  
  
  CONCLUSIONS
  The non-toxigenic O1 and O139 V. cholerae had a wide distribution in the environment of Pearl River estuary water during the non-epidemic period of cholera. All the aquatic isolates presented diversities on the related virulent genes.
authors.affiliation: Institute of Pathogenic Microorganisms, Guangdong Provincial Center for Diseases Control and Prevention, Guangzhou, China.
authors.forename: Bai-sheng
authors.initials: BS
authors.lastname: Li
authors.forename: Duo-chun
authors.initials: DC
authors.lastname: Wang
authors.forename: Hai-ling
authors.initials: HL
authors.lastname: Tan
authors.forename: Bi-xia
authors.initials: BX
authors.lastname: Ke
authors.forename: Jing-diao
authors.initials: JD
authors.lastname: Chen
authors.forename: Dong-mei
authors.initials: DM
authors.lastname: He
authors.forename: Mei-zhen
authors.initials: MZ
authors.lastname: Liu
authors.forename: Xiao-ling
authors.initials: XL
authors.lastname: Deng
authors.forename: Chang-wen
authors.initials: CW
authors.lastname: Ke
authors.forename: Biao
authors.initials: B
authors.lastname: Kan
mesh_terms: D002681:China; D002772:Cholera Toxin / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D004784:Environmental Monitoring; D063366:Estuaries; D045483:Rivers / Q000382:microbiology*; D014734:Vibrio cholerae / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D037521:Virulence Factors; D002772:Cholera Toxin