A new alkaline elastase of an alkalophilic bacillus

A new alkaline elastase was purified from the culture broth of an alkalophilic Bacillus sp. Ya-B. This was a serine proteinase. Molecular weight was 25,000. The optimum pH for elastin and casein was 11.75. The enzyme had very high specific activity, 12,400 units/mg protein for casein, and 2,440 units/mg protein for elastin at the optimum pH. It showed marked preference for elastin. The relative activity of elastin/casein of this enzyme was 17 and 6 times higher than those of subtilisin BPN' and subtilisin Carlsberg, respectively. This enzyme also had higher keratin and collagen hydrolyzing activity in comparison with subtilisin.