Role of the Enterotoxic Hemolysin in Pathogenicity of Vibrio mimicus

Abstract

Vibrio mimicus (V. mimicus) is a causative agent of human gastroenteritis and food poisoning. Although several toxic or virulence factors have been isolated from the bacterium, an enterotoxic hemolysin is a sole toxin produced by all clinical isolates. In the present study, we found that the antibody against the hemolysin significantly inhibited the fluid-accumulating action of the living cells inoculated into a rabbit ileal loop, and that the hemolysin gene (vmhA) was probably expressed by the bacterium in the ileal loop. Additionally, in spit of the comparable motility and similar proteome profiles, a vmhA mutant revealed the reduced fluid-accumulating activity. Theses findings suggest that the hemolysin contributes to full virulence of V. mimicus.