Fig. 2.

VvpS in the supernatants of V. vulnificus and the effects of the protease inhibitors on VvpS activity. (A) Cultures of the wild type and vvpS mutant harboring each plasmid as indicated were grown in LBS for 12 h at 30°C, and the VvpS proteins in the supernatants were determined by Western blot analysis. Complementation of the mutant with a functional vvpS (pMS0746) is also presented, as indicated. Molecular mass markers (Precision Plus Protein standards; Bio-Rad Laboratories) and VvpS proteins (arrow) are shown in kilodaltons. (B) MBP-VvpS protein (100 μM) was used for the determination of protease activity, defined as an azocasein-hydrolyzing activity in the presence of either 1 mM PMSF or 10 mM EDTA. The same amount of MBP protein was used as a negative control. The error bars represent the SEM.