Carrier mediated uptake of dehydroascorbate into higher plant plasma membrane vesicles shows trans-stimulation

被引：38

作者：

Horemans, N ^{[1
]}

Asard, H ^{[1
]}

Caubergs, RJ ^{[1
]}

机构：

[1] Univ Antwerp, Dept Biol, B-2020 Antwerp, Belgium

来源：

FEBS LETTERS | 1998年 / 421卷 / 01期

关键词：

ascorbate; plasma membrane; ascorbate transport; ascorbate/dehydroascorbate carrier; counterflow; Phaseolus;

D O I：

10.1016/S0014-5793(97)01534-2

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：

The activity of the ascorbate (Asc) carrier of purified Phaseolus plasma membranes is demonstrated to be highly stimulated when membrane vesicles are preloaded with Asc. Asc transport is inhibited by DTT but is not affected by glutathione or ferricyanide, indicating that dehydroascorbate (DHA) is the preferred species for uptake, Asc transport in the loaded vesicles showed saturable kinetics with an apparent affinity constant of 24 mu M and maximal uptake rate of 94 pmol/mg/min. Addition of DHA stimulated the efflux of Asc molecules from the loaded vesicles. Together these results suggest the presence of an Asci DHA exchange mechanism in higher plant: plasma membranes. (C) 1998 Federation of European Biochemical Societies.

引用

页码：41 / 44

页数：4

共 22 条

[1] ASCORBATE SYSTEM IN PLANT DEVELOPMENT [J].