Role of a protease in the adherence and enterotoxicity of Vibrio mimicus

The role of protease in the intestinal adherence and enterotoxicity of Vibrio mimicus strain E-33 was investigated by using in vivo ligated rabbit ileal loop model. V. mimicus protease (VMP) was negative in fluid accumulation in the rabbit ileal loop. However, pre-treatment of the loop with purified VMP induced the elevation of fluid accumulation caused by the vibrios with the enhancement of bacterial adherence to the corresponding intestinal mucosa. The augmentation in the fluid accumulation could also be observed in the loop upon supplementation with VMP. In contrast, adherence to the mucosa was reduced by the simultaneous inoculation of VMP. The elevation in the fluid accumulation could also be observed in the loop supplemented or pre-treated with protease from V. cholerae or V. vulnificus. Furthermore, when the vibrios in the loops were accompanied by anti-VMP IgG antibody or inhibitors for VMP, such as ethyleneglycol-bis (β-aminoethylether)- N,N,N',N',-tetraacetic acid or tetraethylenepentamine, reductions in the adherence indices with consequent reductions in the fluid accumulations were observed. It is therefore, suggested that the protease produced by the pathogen contributes significantly toward the pathogenicity of V. mimicus.