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本文利用丙酮处理,硫酸铵沉淀,DEAE纤维素层析,Sephadex G-50凝胶过滤等步骤提纯了蓖麻蚕精氨酸酶。该酶由两个分子量80,000的亚基组成,等电点为5.3,并测定了氨基酸组成。动力学实验表明酶的K_m值为20m M,精氨酸代谢的产物鸟氨酸及脯氨酸对该酶有竞争性抑制作用,最适pH为9.0,Mn~(++)为酶表现活力所必需。苯甲磺酰氟及巯基乙醇可能通过作用于酶活性基团和影响其高级结构而抑制该酶。此外,还将蓖麻蚕精氮酸酶与大鼠及鸡肝脏精氨酸酶进行了一些比较。
In this paper, Acetone treatment, ammonium sulfate precipitation, DEAE cellulose chromatography, Sephadex G-50 gel filtration and other steps to purify the castor bean arginase. The enzyme consists of two subunits of 80,000 molecular weight with an isoelectric point of 5.3 and the amino acid composition was determined. Kinetic experiments showed that the enzyme Km value of 20m M, arginine metabolites ornithine and proline competitive inhibition of the enzyme, the optimum pH of 9.0, Mn ~ (++) for the enzyme activity Necessary. Phenylmethanesulfonyl fluoride and mercaptoethanol may inhibit this enzyme by acting on the enzyme active group and affecting its higher structure. In addition, a comparison was made between castor-silkworm laccase and rat and chicken liver arginase.