Improvement of thermal stability of Leuconostoc pseudomesenteroides glucose-6-phosphate dehydrogenase
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چکیده
Glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) from Leuconostoc pseudomesenteroides (the previously named: Leuconostoc mesenteroides) catalyzes the oxidation of glucose-6-phosphate in the presence of the coenzyme NADP or NAD. The enzyme is one of the industrially important enzymes and is applied in clinical settings. It is mainly useful in determinations of glucose and creatine kinase by coupling with hexokinase (EC 2.7.1.1; ATP: D-hexose 6-phosphotransferase) or glucokinase (EC 2.7.1.2; ATP: D-glucose 6-phosphotransferase) . G6PDH has been cloned and expressed in Escherichia coli, and its tertiary structure has been determined in the presence of substrates, coenzymes, or both. The catalytic function of G6PDH has been also investigated by site-directed mutagenesis. The enhancement of enzyme thermostability is one of the important approaches in protein engineering. Using thermostable enzymes in clinical diagnostic reagents offers the benefits of longer reagent shelf-lives at normal storage temperatures. We have already described the enhancement of the thermal stability of Saccharomyces pastorianus hexokinase as well as the mutational effects of the amino Journal of Analytical Bio-Science Vol. 33, No 4 (2010)
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تاریخ انتشار 2010