KINETICS OF INHIBITION OF GREEN CRAB (SCYLLA-SERRATA) ALKALINE-PHOSPHATASE BY PHENYLGLYOXAL

The kinetics method of the substrate reaction during modification of e nzyme activity previously described by Tsou (Adv. Enzymol. Related. Ar eas Mel. Biol., 1988, 61, 381-436) has been applied to study the kinet ics of the course of inactivation of green crab alkaline phosphatase b y phenylglyoxal. The obtained results shows that the inactivation of t he enzyme by phenylglyoxal is a slow reversible reaction. The microsco pic rate constants for the reaction of the inhibitor with the enzyme w ere determined. The presence of substrate offers marked protection of this enzyme against inactivation by phenylglyoxal. The above results s uggest that tile arginine residue is essential for activity and is sit uated at the active site of the enzyme.