Studies on the temperature-dependent autoinhibition of human plasma kallikrein I.
At 37 degrees C, human plasma kallikrein I follows Michaelis-Menten behaviour and exhibits a normal linear relationship between the initial velocity of hydrolysis of Ac-Pro-Phe-Arg-OMe,HCl and enzyme concentration in the range 0--150 pM. At temperatures of 30 degrees C and below substantial deviations from linearity are observed over the same enzyme concentration range. The temperature-dependent autoinhibition of kallikrein I activity is reversible and is not due to low-molecular-weight endogenous inhibitors or cofactors. The kinetic effect is apparently due to aggregation and can be abolished by the addition of sodium deoxycholate.
D001665:Binding Sites; D003067:Coenzymes / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D006868:Hydrolysis; D007610:Kallikreins / Q000378:metabolism*; D007700:Kinetics; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D013696:Temperature
D003067:Coenzymes; D012967:Sodium Dodecyl Sulfate; D007610:Kallikreins