Activation of the Urease - Urea System Using Crude and Crystalline

Many studies of the kinetics of enzyme action as a function of temperature have been made. The older work (for reference cf. Haldane, 1930; Tauber, 1937) indicates that while the velocity of an enzyme-catalyzed reaction increases with rise in temperature, up to the inactivation temperature of the enzyme, this change in rate is not an exponential function of the absolute temperature. I t has been pointed out by Bodansky (1937), however, that in many cases the velocity constants for enzyme reactions have been improperly computed. Certain recent work, on the other hand, (Crozier, 1924; Craig, 1936; Sizer, !937, 1938 a, b; Gould and Sizer, 1938) indicates that for the fat oxidase from Lupinus albus, for yeast invertase either partially purified or present in the living cells, and for the anaerobic dehydrogenase system of E. coli, the reaction velocity increases exponentially with temperature according to the Arrhenius equation