3β-Brassinosteroid dehydrogenase activity in Arabidopsis and tomato

被引：10

作者：

Stündl, U ^{[1
]}

Schneider, B ^{[1
]}

机构：

[1] Max Planck Inst Chem Okol, D-07745 Jena, Germany

来源：

PHYTOCHEMISTRY | 2001年 / 58卷 / 07期

关键词：

Arabidopsis thaliana; Lycopersicon esculentum; biosynthesis; brassinosteroids; 3-dehydro-24-epiteasterone; 24-epiteasterone; 3 beta-steroid dehydrogenase;

D O I：

10.1016/S0031-9422(01)00387-9

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：

Enzymatic conversion of 24-epiteasterone to 3-dehydro-24-epiteasterone, representing a reversible step in the biosynthesis of 24R-methyl brassinosteroids, was monitored in vitro in Arabidopsis thaliana and Lycopersicon esculentum using fluorescent tagging and HPLC analysis. In both species 24-epiteasterone was metabolized by the cytosolic fraction of induced root-callus suspension cultures in a NAD dependent manner. This 3 beta -dehydrogenation was only slightly inhibited by 12-fold excess of other 3 beta -hydroxy intermediates of the early cathasterone) and late C-6 oxidation pathway (6-deoxo-cathasterone, 6-deoxo-teasterone), indicating a rather specific protein, 3-Dehydro-6-deoxoteasterone and 3 alpha -hydroxy intermediates of brassinosteroid biosynthesis did not reduce conversion of 24-epiteasterone to 3-dehydro-24-epiteasterone. In contrast to light-grown cultures the reaction was clearly inhibited in the dark. (C) 2001 Elsevier Science Ltd. All rights reserved.

引用

页码：989 / 994

页数：6

共 28 条

[1] Molecular physiology of brassinosteroids revealed by the analysis of mutants [J].