大豆种子芳基酰胺酶活性的部分纯化及特性分析

Partial purification and characterization of soybean seed arylamidase activity.

作者信息

Alves K B, Noguti M A

机构信息

Departamento de Bioquímica, Escola Paulista de Medicina, São Paulo, Brasil.

出版信息

Braz J Med Biol Res. 1989;22(9):1073-5.

PMID:2636005

Abstract

The arylamidase activity of a soybean seed extract was measured using L-aminoacyl-2-naphthylamides and L-Leu-p-nitroanilide. The enzyme preparation was purified 42-fold with 45% yield, by precipitation with 25-75% ammonium sulfate saturation and by ion exchange and gel filtration chromatography. The highest kcat/Km ratio was that of L-Lys-2-naphthylamide (216 s-1 microM-1) and the lowest was that of L-Leu-p-nitroanilide (40 s-1 microM-1). Enzyme activity was inhibited by -SH and -S-S-group reagents while chelating agents had no effect. L-Lysine, L-leucine, puromycin and bestatin were competitive inhibitors and the Ki values found were: 3.5 mM, 0.9 mM, 0.23 mM and 0.8 microM, respectively.

摘要

使用L-氨基酰基-2-萘酰胺和L-亮氨酰对硝基苯胺测定了大豆种子提取物的芳基酰胺酶活性。通过用25 - 75%硫酸铵饱和度沉淀、离子交换和凝胶过滤色谱法，该酶制剂被纯化了42倍，产率为45%。最高的kcat/Km比值是L-赖氨酸-2-萘酰胺的（216 s-1 μM-1），最低的是L-亮氨酰对硝基苯胺的（40 s-1 μM-1）。酶活性受到-SH和-S-S-基团试剂的抑制，而螯合剂没有影响。L-赖氨酸、L-亮氨酸、嘌呤霉素和贝他汀是竞争性抑制剂，发现的Ki值分别为：3.5 mM、0.9 mM、0.23 mM和0.8 μM。