Abstract

In general, the salinity of the ocean is close to 3.5% and marine vibrios possess the respiratory chainlinked Na+ pump. The influence of sodium chloride and the proton conductor carbonylcyanide m-chlorophenylhydrazone (CCCP) on the production of extracellular proteases in a marine Vibrio strain was examined. At the concentration of 0.5 M, sodium chloride minimally inhibited the activity of extracellular proteases by approximately 16%, whereas at the same concentration, the producton of extracellular proteases was severely inhibited. On the other hand, the production of extracellular proteases was completely inhibited by the addition of 2 μM CCCP at pH 8.5, where the respiratory chain-linked Na^+ pump functions.

• Keywords: a marine bacterium; Vibrio sp. strain 60; extracellular protease producton; NaCl; CCCP