[Specific control over the synthesis of plasmin-like and plasminogen-activating proteinases in marine bacteria]

The biosynthesis of proteinases with various substrate specificities was studied in Bacillus firmus 44b and Bacillus oligonitrophilus 21p as influenced by the growth conditions and growth phases of the bacteria. The period of the maximum synthesis of plasmin-like enzymes was observed 6 h later than the period of the maximum growth rate period of B. firmus 44b, and 3 h as compared to the growth rate of B. oligonitrophilus 21p. The periods of the maximum accumulation of activating enzymes were delayed 9 and 12 h, respectively, as compared to the rapid growth periods of these two bacteria. Catabolite repression of proteinase synthesis and stimulation of the latter with substrate proteins were insignificant. The production of both plasmin-like and plasminogen-activating enzymes was most sensitive to repression by nitrogen deficiency. The production of plasminogen-activating proteinases was less dependent on the carbon source than the production of plasmin-like enzymes.