Inhibition kinetics of green crab (Scylla serrata) alkaline phosphatase by zinc ions: A new type of complexing inhibition

Department of Biology, Xiamen University, Amoy, Fujian, China
Biochimica et Biophysica Acta (Impact Factor: 4.66). 03/2001; 1545(1-2):6-12. DOI: 10.1016/S0167-4838(00)00254-5
Source: PubMed


The Tsou method was used to study the kinetic course of inactivation of green crab alkaline phosphatase by zinc ions. The results show that the enzyme was inactivated by a complexing scheme which has not been previously identified. The enzyme first reversibly and quickly binds Zn(2+) and then undergoes a slow reversible course to inactivation and slow conformational change. The inactivation reaction is a single molecule reaction and the apparent inactivation rate constant is for a saturated reaction being independent of Zn(2+) concentration if the concentration is sufficiently high. The microscopic rate constants of inactivation and the association constant were determined from the measurements.

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Available from: Rong Qing Zhang, May 08, 2015
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    • "However, the enzyme was inhibited by zinc at higher concentration (p < 0.01, Table 2). Zhang et al. (2001) studied the kinetics of inactivation of alkaline phosphatase from green crab by zinc ions. The enzyme reversibly and quickly bound Zn 2+ and then underwent a slow, reversible inactivation and slow conformational change. "
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