Glucose polyester biosynthesis. Purification and characterization of a glucose acyltransferase

被引：46

作者：

Li, AX ^{[1
]}

Eannetta, N ^{[1
]}

Ghangas, GS ^{[1
]}

Steffens, JC ^{[1
]}

机构：

[1] Cornell Univ, Dept Plant Breeding, Ithaca, NY 14853 USA

来源：

PLANT PHYSIOLOGY | 1999年 / 121卷 / 02期

关键词：

D O I：

10.1104/pp.121.2.453

中图分类号：

Q94 [植物学];

学科分类号：

071001 ;

摘要：

Glandular trichomes of the wild tomato species Lycopersicon pennellii secrete 2,3,4-O-tri-acyl-glucose (-Glc), which contributes to insect resistance. A Glc acyltransferase catalyzes the formation of diacyl-Glc by disproportionating two equivalents of 1-O-acyl-beta-Glc, a high-energy molecule formed by a UDP-Glc dependent reaction. The acyltransferase was purified 4,900-fold from L. pennellii leaves by polyethylene glycol fractionation, diethylaminoethyl chromatography, concanavalin A affinity chromatography, and chromatofocusing. The acyltransferase possesses an isoelectric point of 4.8, a relative molecular mass around 110 kD, and is composed of 34- and 24-kD polypeptides as a heterotetramer. The 34- and 24-kD proteins were partially sequenced. The purified enzyme catalyzes both the disproportionation of 1-O-acyl-beta-Glcs to generate 1,2-di-O-acyl-beta-Glc and anomeric acyl exchange between 1-O-acyl-beta-Glc and Glc.

引用

页码：453 / 460

页数：8

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