A RADIOASSAY FOR DIHYDROPTEROATE-SYNTHESIZING ENZYME ACTIVITY

被引：16

作者：

OKINAKA, O

IWAI, K

机构：

[1] Research Institute for Food Science, Kyoto University, Sakyo-ku, Kyoto

来源：

ANALYTICAL BIOCHEMISTRY | 1969年 / 31卷 / 1-3期

关键词：

D O I：

10.1016/0003-2697(69)90255-3

中图分类号：

Q5 [生物化学];

学科分类号：

071010 ; 081704 ;

摘要：

A simple and rapid radioassay procedure for dihydropteroate synthetase using 14C-labeled p-aminobenzoic acid as substrate has been described. The assay procedure is based on the direct measurement of the formation of 14C-labeled dihydropteroic acid from 14C-labeled p-aminobenzoic acid and 2-amino-4-hydroxy-6-pyrophosphorylmethyldihydropteridine according to prescribed conditions. The labeled dihydropteroic acid produced by the enzymic reaction is separated easily and satisfactorily from the labeled substrate by paper chromatography, and the radioactivity of the paper section containing the labeled product is counted in a liquid scintillation counting system. The formation of dihydropteroic acid can be measured at a level of 10-11 mole by employing labeled p-aminobenzoic acid of a specific activity of 10 μc/μmole. By applying this procedure, the distribution of the enzyme in several higher plants has been investigated. © 1969.

引用

页码：174 / &