Purification and characterization of glutamate decarboxylase from cowpea

被引：63

作者：

Johnson, BS ^{[1
]}

Singh, NK ^{[1
]}

Cherry, JH ^{[1
]}

Locy, RD ^{[1
]}

机构：

[1] AUBURN UNIV,DEPT BOT & MICROBIOL,AUBURN,AL 36849

来源：

PHYTOCHEMISTRY | 1997年 / 46卷 / 01期

关键词：

Vigna unguiculata; Leguminosae; cowpea; enzymology; glutamate decarboxylase; GABA; purification;

D O I：

10.1016/S0031-9422(97)00236-7

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：

Glutamate decarboxylase (GAD) was purified 300-fold from green cowpea (Vigna unguiculata L.) pods using a combination of PEG precipitation, DEAE cellulose chromatography, hydroxylapatite chromatography, and Q-resin chromatography. The partially purified preparation demonstrated 2 primary bands in SDS-polyacrylamide gel electrophoresis with up to 3 additional minor bands. Cowpea GAD has a pH optimum at between pH 5.5-6.0, and an apparent K-M for glutamate of 3.2 mM at pK 5.8. Both crude GAD preparations and preparations partially purified through the hydroxylapatite step can be stimulated by Ca2+ and calmodulin when assayed at pH 5.8. However, the purified enzyme does not show activation by Ca2+ and/or calmodulin at pH 5.8 or at pH 7.0. (C) 1997 Elsevier Science Ltd. All rights reserved.

引用

页码：39 / 44

页数：6

共 26 条

[1] MOLECULAR AND BIOCHEMICAL-ANALYSIS OF CALMODULIN INTERACTIONS WITH THE CALMODULIN-BINDING DOMAIN OF PLANT GLUTAMATE-DECARBOXYLASE [J].