人的基因工程氨酰基脯氨酸二肽酶的多效酶活性(英文)

目的　研究人氨酰基脯氨酸二肽酶除催化水解C端为脯氨酸残基的二肽外 ,是否还有G类有机磷化合物水解酶 (G酶)活性。方法　用基因工程技术克隆及表达人的重组氨酰基脯氨酸二肽酶。氨酰基脯氨酸二肽酶及G酶活性用常规方法测定。结果　COS 7细胞表达的人氨酰基脯氨酸二肽酶催化有机磷化合物梭曼的水解 ,也水解二肽化合物Gly Pro。两种活性比未转染的COS 7细胞高 2倍。比较转染了带有氨酰基脯氨酸二肽酶基因的重组载体的COS 7细胞和对照组细胞中的两种酶活性 ,可以看到有平行的升高趋势及恒定的酶活性比值。结论G酶和氨酰基脯氨酸二肽酶为同一个酶 ,或至少属于同工酶

Pleiotropic enzyme activities of genetically engineered human prolidase

AIM To investigate whether the human pro- li dase possesses the G-type organophosphate hydrolyzing enzyme(Gase) activity besides its ability to catalyze the hydrolysis of the dipeptides bearing a proline resid ue at the C-terminus. METHODS Genetic engineering techniques were used in the cloning and expression of the recombinant human prolidase. Prolidas e and Gase activities were assayed in the conventional ways. RESULTS The recombinant human prolidase expressed in COS-7 cells catalyzed the hydrolysis of organophosphorous compound soman as well as the hydrolysis of dipe ptide Gly-Pro. Both activities were two-folds higher than that in the non-tr ansformed COS-7 counterpart. Comparison between the two activities in COS-7 c ells transfected with the recombinant vector containing the prolidase gene and t he control cells showed parallel elevation with a constant ratio. CONCLUSI ON It is infered that the Gase and the prolidase are of the same enzyme, or at least belong to isozyme.