CHARACTERIZATION AND SOLUBILIZATION OF KAURENOIC ACID HYDROXYLASE FROM GIBBERELLA-FUJIKUROI

被引：24

作者：

JENNINGS, JC ^{[1
]}

COOLBAUGH, RC ^{[1
]}

NAKATA, DA ^{[1
]}

WEST, CA ^{[1
]}

机构：

[1] UNIV CALIF LOS ANGELES,DEPT CHEM,LOS ANGELES,CA 90024

来源：

PLANT PHYSIOLOGY | 1993年 / 101卷 / 03期

关键词：

D O I：

10.1104/pp.101.3.925

中图分类号：

Q94 [植物学];

学科分类号：

071001 ;

摘要：

A key step in gibberellin biosynthesis is the conversion of ent-kaurenoic acid to ent-7alpha-hydroxykaurenoic acid, mediated by the enzyme kaurenoic acid hydroxylase. A cell-free system obtained from Gibberella fujikuroi (Saw.) Wr. was used to characterize kaurenoic acid hydroxylase activity. Microsomal preparations f rom disrupted fungal cells, in the presence of O2 and NADPH, converted [17-C-14]ent-kaurenoic acid to oxidation products that were separated by high-performance liquid chromatography and identified as ent-7alpha-hydroxykaurenoic acid and gibberellin A14 by combined gas chromatography-mass spectrometry. Flavin adenine dinucleotide and the chloride salts of several monovalent cations stimulated the conversion of ent-kaurenoic acid to these products, whereas CO and a number of known inhibitors of cytochrome P-450-dependent reactions, including paclobutrazol, tetcyclacis, BAS lll..W, flurprimidol, triarimol, metyrapone, and 1-phenylimidazole, significantly reduced kaurenoic acid hydroxylase activity. Kaurenoic acid hydroxylase was solubilized from fungal microsomes by treatment with 1 M KCl. The properties of the enzyme noted above suggest that kaurenoic acid hydroxylase from G. fujikuroi is a cytochrome P-450-dependent monooxygenase.

引用

页码：925 / 930

页数：6