Article

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

ABSTRACT

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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    • "La información sobre las propiedades y características que existe sobre la FA de crustáceos proviene tanto de especies silvestres como cultivadas, principalmente de Pandalus borealis (Olsen et al., 1991; Zhisheng et al., 2010; Rader et al., 2012), Penaeus japonicus (Chuang y Shih, 1990), Penaeus monodon (Lee y Chuang, 1991), Marsupenaeus japonicus (Zhan et al., 2004), así como también en cangrejos como Scylla serrata (Zhang et al., 2000; Zhang et al., 2001). Estos trabajos abordan temas sobre estructura, sitio activo, inhibidores y estabilidad térmica (Nilsen et al., 2001; Zhang et al., 2001). Asimismo, establecen el papel que juega esta enzima en el sistema digestivo y el sistema inmune de los camarones, principalmente en cultivo (Ivancic et al., 2010; Rivera et al., 2011a; Rivera et al., 2011b; Wang et al., 2009). "

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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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