Kinetics of inhibition of green crab (Scylla serrata) alkaline phosphatase by L-cysteine.
The inhibition of alkaline phosphatase from green crab (Scylla serrata) by L-cysteine has been studied. The results show that L-cysteine gives a mixed-type inhibition. The progress-of-substrate-reaction method previously described by Tsou [(1988), Adv. Enzymol. Related Areas Mol. Biol. 61, 391-436] was used to study the inactivation kinetics of the enzyme by L-cysteine. The microscopic rate constants were determined for reaction of the inhibitor with the free enzyme and the enzyme-substrate complex (ES) The results show that inactivation of the enzyme by L-cysteine is a slow, reversible reaction. Comparison of the inactivation rate constants of free enzyme and ES suggests that the presence of the substrate offers marked protection of this enzyme against inactivation by L-cysteine.
Zhu
C M
CM
Department of Biological Science and Biotechnology, Tsinghua University, Beijing, China.
Chen
Q X
QX
Lin
H N
HN
Yang
Y
Y
Park
Y D
YD
Zhang
R Q
RQ
Zhou
H M
HM
D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors*; D000818:Animals; D003386:Brachyura / Q000201:enzymology*; D003545:Cysteine / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007700:Kinetics; D013379:Substrate Specificity
D004791:Enzyme Inhibitors; D000469:Alkaline Phosphatase; D003545:Cysteine