以N-乙酰-苯丙氨酰-3-硫代苯丙氨酸为底物测定羧肽酶A：在血清直接检测中的应用

Determination of carboxypeptidase A using N-acetyl-phenylalanyl-3-thiaphenylalanine as substrate: application to a direct serum assay.

作者信息

Brown K S, Kingsbury W D, Hall N M, Dunn G L, Gilvarg C

出版信息

Anal Biochem. 1987 Feb 15;161(1):219-25. doi: 10.1016/0003-2697(87)90674-9.

Abstract

N-Acetyl-L-phenylalanyl-L-3-thiaphenylalanine has been shown to be a substrate for carboxypeptidase A. Hydrolysis of the compound obeys Michaelis-Menten kinetics with a KM of 0.22 mM and a kcat of 6720 min-1 at 22 degrees C. A colorimetric assay, employing Ellman's reagent to detect the thiophenol released upon cleavage of the peptide, has been developed. The assay can be used for the direct determination of carboxypeptidase A in serum.

摘要

N-乙酰-L-苯丙氨酰-L-3-噻吩丙氨酸已被证明是羧肽酶A的一种底物。该化合物的水解遵循米氏动力学，在22℃时，米氏常数（KM）为0.22 mM，催化常数（kcat）为6720 min-1。已开发出一种比色测定法，使用埃尔曼试剂检测肽裂解时释放的苯硫酚。该测定法可用于直接测定血清中的羧肽酶A。