期刊
FEBS LETTERS
卷 580, 期 27, 页码 6428-6434出版社
WILEY
DOI: 10.1016/j.febslet.2006.10.058
关键词
erythroascorbic acid; ascorbic acid; D-arabinose; dehydrogenase; L-galactose dehydrogenase; higher plants; Saccharomyces cerevisiae
Erythroascorbic acid (eAsA) is a five-carbon analog of ascorbic acid, and it is synthesized from D-arabinose by D-arabinose dehydrogenase (ARA) and D-arabinono-gamma-lactone oxidase. We found an NAD(+)-specific ARA activity which is operative under submillimolar level Of D-arabinose in the extracts of Saccharomyces cerevisiae. The hypothetical protein encoded by YMR041c showed a significant homology to a L-galactose dehydrogenase which plays in plant ascorbic acid biosynthesis, and we named it as Ara2p. Recombinant Ara2p showed NAD(+)-specific ARA activity with K-m = 0.78mM to D-arabinose, which is 200-fold lower than that for the conventional NADP(+)-specific ARA, Ara1p. Gene disruptant of ARA2 lost entire NAD(+)-specific ARA activity and the conspicuous increase in intracellular eAsA by exogenous D-arabinose feeding, while the double knockout mutant of ARA1 and ARA2 still retained measurable amount of eAsA. It demonstrates that Ara2p, not Ara1p, mainly contributes to the production of eAsA from D-arabinose in S. cerevisiae. (c) 2006 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据