Suppression of an exocellular proteinase synthesis in Bacillus megaterium by increased temperature.

During cultivation of Bacillus megaterium at 42 degrees C the amount of the exocellular protease produced by growing cells sharply decreases as compared with temperatures of 28 and 35 degrees C. Within the above range the growth rate and incorporation of amino acids increase with increasing temperature. The culture adapted to 42 degrees C does not produce more proteinase at this temperature than the non-adapted culture. The high temperature does not induce accumulation of the enzyme in the cells. Total protein excretion was slightly lower at 42 degrees C than at 28 and 35 degrees C.