2Department of Biological Science and Biotechnology, Tsinghua University, Beijing 100084, People's Republic of China; E-mail: zhm-dbs@mail.tsinghua.edu.cn
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Received July 27, 1998
The kinetics of thermal inactivation of Penaeus penicillatus acid phosphatase have been studied using a kinetic method related to the substrate reaction during irreversible inhibition of the enzyme activity as previously described by Tsou (Adv. Enzymol. Relat. Areas Mol. Biol. (1988) 61, 381-436). The kinetics of thermal inactivation of the enzyme show that the reaction is irreversible. The microscopic rate constants were determined for thermal inactivation of free enzyme and the enzyme--substrate complex. The results show that the presence of substrate has a significant protective effect against thermal inactivation of the enzyme.
KEY WORDS: acid phosphatase, kinetic analysis, thermal inactivation