Distribution of genes encoding four pathogenicity islands (VPaIs), T6SS, biofilm, and type I pilus in food and clinical strains of Vibrio parahaemolyticus in China.
Vibrio parahaemolyticus is a major cause of foodborne gastroenteritis in China, Japan, and other countries. The pandemic O3:K6 clone, which harbors thermostable direct hemolysin [tdh] gene and toxRS/new gene, is mainly responsible for the foodborne outbreaks after 1995. Previous studies showed that genes in the pathogenicity island-1 (VPaI-1) and VPaI-5 are harbored only by pandemic strains, whereas genes in VPaI-7 and type III secretion system 2 are closely associated with tdh-positive strains of V. parahaemolyticus. In this study, we examined the distribution of genes encoding VPaI-2, VPaI-3, VPaI-4, VPaI-6, type VI secretion systems (T6SS), biofilm, and type I pilus in 71 food and 116 clinical strains of V. parahaemolyticus. The results showed that most of the pandemic strains of V. parahaemolyticus harbored the complete genes of VPaI-2, T6SS, and type I pilus. In contrast, most of the pathogenic strains (harboring tdh gene or TDH-related hemolysin [trh] gene) and nonpathogenic strains (harboring neither tdh gene nor trh gene) contained partial genes of VPaI-2, T6SS, and type I pilus. Genes of VPaI-4 were exclusively present in the pandemic strains. Genes of VPaI-3 were present in most of the pandemic strains and a small percentage of nonpathogenic strains, mainly O3:K6 strains. VPaI-6 and biofilm-associated genes were harbored by almost all the strains, irrespective of their pandemic, pathogenic, or nonpathogenic traits.
Chao
Guoxiang
G
Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
Jiao
Xinan
X
Zhou
Xiaohui
X
Wang
Fang
F
Yang
Zhenquan
Z
Huang
Jinlin
J
Pan
Zhiming
Z
Zhou
Liping
L
Qian
Xiaoqin
X
D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism; D018441:Biofilms; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D010861:Fimbriae, Bacterial / Q000235:genetics*; D005516:Food Microbiology; D005517:Foodborne Diseases / Q000517:prevention & control; D005798:Genes, Bacterial; D044404:Genomic Islands; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D016133:Polymerase Chain Reaction; D017747:Seafood / Q000382:microbiology; D055571:Secretory Pathway; D013045:Species Specificity; D014735:Vibrio Infections / Q000453:epidemiology / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D037521:Virulence Factors; C068489:thermostable direct hemolysin