Biosynthesis of unsaturated fatty acids by bacilli. Hyperinduction and modulation of desaturase synthesis.

desaturating enzyme.This inactivation, in uiuo, followed first order kinetics at all temperatures, and the enzyme half-life was determined solely by the incubation temperature (15,17).A second control process was that of desaturase induction (9, 10).B. megaterium cultures growing at 35" did not contain unsaturated fatty acids nor did they show desaturase activity.When these cultures were transferred to 20", however, synthesis of desaturase began within 5 min and continued at a high rate for about 1 h (13).