STERIC EFFECTS IN ACYLATION OF ALPHA-CHYMOTRYPSIN

被引：28

作者：

MILSTIEN, JB

FIFE, TH

机构：

[1] Department of Biochemistry, University of Southern California, Los Angeles, California

来源：

BIOCHEMISTRY | 1969年 / 8卷 / 02期

关键词：

D O I：

10.1021/bi00830a024

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

The acylation of α-chymotrypsin by esters of p-nitrophenol has been investigated atvarious pH values at 25°. Esters studied included acetate, propionate, butyrate, hexanoate, isobutyrate, isovalerate, trimethylacetate, and 3,3-dimethylbutyrate. With the exception of p-nitrophenyl hexanoate, the reaction shows a normal steric order of reactivity, increased branching decreasing the rate of enzymatic acylation. Under the conditions of this study, the acylation reaction was experimentally second order. A plot of log (k2/Km)rel vs. the Taft steric effect constants, Es, was linear with a slope of 0.95 ± 0.22. This issimilarto the slope of log k3 vs. Es found in the deacylation reaction. © 1969, American Chemical Society. All rights reserved.

引用

页码：623 / &

共 17 条

[1] ON THE INTERPRETATION OF THE PH VARIATION OF THE MAXIMUM INITIAL VELOCITY OF AN ENZYME-CATALYZED REACTION [J].