Role of Vibrio mimicus protease in enterotoxigenicity.

Recently, we have purified and characterised a metalloprotease produced by Vibrio mimicus. The role of V. mimicus protease (VMP) in fluid accumulation (FA) in rabbit ileal loops (RIL) was investigated. Although live cells or crude VMP prepared from cell-free culture supernatant showed activity in RIL, the purified VMP failed to induce FA in the RIL. When VMP in crude preparation was inactivated by preparing the fraction in the presence of EGTA (Ethyleneglycol-bis [beta-aminoethylether]-N, N, N1, N1,-tetraacetic acid), a chelating agent for Ca2+ (EGTA-crude), or treatment with phosphoramidon (a metalloprotease inhibitor), the preparation became negative in RIL assay. Again, the EGTA-crude induced FA in RIL when retreated with 2mM CaCl2 after elimination of EGTA. The results show evidences of attribution of VMP in RIL activity. These observations, therefore, suggest that the protease produced by V. mimicus may play a potential role in enterotoxigenicity.