Studies on the spores of aerobic bacteria. IV. A heat resistant catalase from spores of Bacillus terminalis.

In the course of investigating the enzyme content of spores of Bacillus terminalis (since identified as a strain of Bacilu cereus), the observation was made that well cleaned spores exhibited considerable catalase activity. Such activity in a spore preparation can be attributed in most cases to improper cleaning, as stressed by Hardwick and Foster (1953). In our case, however, it was found that the catalase activity remained unchanged after repeated washings, indicating that the enzyme was associated intimately with the spore. This was inferred also by the finding that the activity of the spores remained unaltered by heating to 80 C for 30 minutes or to 100 C for 5 minutes. The catalase activity of the vegetative cells is destroyed completely by such treatment. The high heat resistance of this enzyme aociated with spores is analogous to the alanine racemase previously reported by Stewart and Halvorson (1953). This report is concerned with a study of the heat resistant characteristics of this enzyme.