DIRECT SPECTROPHOTOMETRIC MEASUREMENT OF SMALL KINETIC ISOTOPE EFFECTS

被引：24

作者：

ROSENBERG, S ^{[1
]}

KIRSCH, JF ^{[1
]}

机构：

[1] UNIV CALIF BERKELEY,DEPT BIOCHEM,BERKELEY,CA 94720

来源：

ANALYTICAL CHEMISTRY | 1979年 / 51卷 / 09期

关键词：

D O I：

10.1021/ac50045a010

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

A method is described for the measurement of heavy atom kinetic isotope effects by directly determining the rate differences due to isotopic substitution. This is accomplished by measuring the rates of reaction of highly enriched reactants compared with compounds of natural abundance using a high precision spectrophotometer interfaced to a teletype via a microprocessor for automated digital readout. The spectrophotometry data are fit directly to the relevant rate expression by nonlinear least squares regression analysis. Applications of this method to the measurement of oxygen-18 leaving group kinetic isotope effects on the reaction of nicotinamide with 2,4-dinitrophenyl acetate and on the β-galactosidase catalyzed hydrolysis of p-nitrophenyl-β-d-galactoside are given. © 1979, American Chemical Society. All rights reserved.

引用

页码：1379 / 1383

页数：5

共 15 条

[1]

CLELAND WW, 1977, ISOTOPE EFFECTS ENZY, P122

[2]

Conchie J, 1963, METHODS CARBOHYDRATE, V2, P335

[3] APPLICATION OF SECONDARY ALPHA-DEUTERIUM KINETIC ISOTOPE EFFECTS TO STUDIES OF ENZYME CATALYSIS . GLYCOSIDE HYDROLYSIS BY LYSOZYME AND BETA-GLUCOSIDASE [J].