Kinetics of Inhibition of Polyphenol Oxidase Obtained from Tobacco Nicotiana Tobacum

Kinetics of Inhibition of Polyphenol Oxidase Obtained from Tobacco Nicotiana Tobacum

刘卫群;饶学明;潘继承;周海梦

【期刊名称】《清华大学学报（英文版）》 【年(卷),期】2004(009)001

【摘要】In this study, the kinetics of inhibition of polyphenol oxidase by L-cysteine has been investigated.The inhibition of tobacco polyphenol oxidase was studied using the progress-of-substrate-reaction method proposed by Tsou, following the substrate reaction during irreversible inhibition of the enzyme activity. Analysis of the inhibition kinetics shows that inhibition occurs by an irreversible and non-complexation reaction. The microscopic rate constants were determined for reaction of the inhibitor both with the free enzyme and with the enzyme-substrate complex. The results show that the presence of the substrate has a significant protective effect of the enzyme against inactivation by L-cysteine.

【总页数】4页(94-97)

【关键词】tobacco;polyphenol oxidase;kinetics;irreversible inhibition 【作者】刘卫群;饶学明;潘继承;周海梦

【作者单位】College of Agronomy, Henan Agricultural University, Zhengzhou 450002, China ;College of Agronomy, Henan Agricultural University, Zhengzhou 450002, China ;Department of Biological Sciences