ELASTOLYTIC ACTIVITY OF A MARINE ISOLATE OF BACILLUS-PUMILUS

Elastolytic activity of the halotolerant strain Bacillus pumilus CMM 5 21, isolated from an unidentified sponge obtained from a depth of 120 m near Iturup Island (the Kurile Islands), was investigated. The strai n was grown in a peptone-yeast extract medium supplemented with elasti n and seawater. Elastase was shown to be a secretory enzyme. Specific elastolytic activity of the culture was maximal after 48 h of growth. The enzyme was partially purified from the culture liquid by fractiona tion with ammonium sulfate. The elastase purified in this manner exhib ited a specific activity of 119 units/mg protein. Elastase was found t o be a thermolabile metal-dependent enzyme with a pH-optimum from 8.0 to 9.0. In the presence of 0.5% NaCl, the enzyme retained 85% of its a ctivity.