Arabidopsis VTC2 Encodes a GDP-l-Galactose Phosphorylase, the Last Unknown Enzyme in the Smirnoff-Wheeler Pathway to Ascorbic Acid in Plants
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منابع مشابه
Arabidopsis VTC2 encodes a GDP-L-galactose phosphorylase, the last unknown enzyme in the Smirnoff-Wheeler pathway to ascorbic acid in plants.
The first committed step in the biosynthesis of L-ascorbate from D-glucose in plants requires conversion of GDP-L-galactose to L-galactose 1-phosphate by a previously unidentified enzyme. Here we show that the protein encoded by VTC2, a gene mutated in vitamin C-deficient Arabidopsis thaliana strains, is a member of the GalT/Apa1 branch of the histidine triad protein superfamily that catalyzes ...
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The L-galactose (Smirnoff-Wheeler) pathway represents the major route to L-ascorbic acid (vitamin C) biosynthesis in higher plants. Arabidopsis thaliana VTC2 and its paralogue VTC5 function as GDP-L-galactose phosphorylases converting GDP-L-galactose to L-galactose-1-P, thus catalyzing the first committed step in the biosynthesis of L-ascorbate. Here we report that the L-galactose pathway of as...
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The Arabidopsis thaliana VTC2 gene encodes an enzyme that catalyzes the conversion of GDP-L-galactose to L-galactose 1-phosphate in the first committed step of the Smirnoff-Wheeler pathway to plant vitamin C synthesis. Mutations in VTC2 had previously been found to lead to only partial vitamin C deficiency. Here we show that the Arabidopsis gene At5g55120 encodes an enzyme with high sequence id...
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In the past year, the last missing enzyme of the L-galactose pathway, the linear form of which appears to represent the major biosynthetic route to L-ascorbate (vitamin C) in higher plants, has been identified as a GDP-L-galactose phosphorylase. This enzyme catalyzes the first committed step in the synthesis of that vital antioxidant and enzyme cofactor. Here, we discuss how GDP-L-galactose pho...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 2007
ISSN: 0021-9258
DOI: 10.1074/jbc.m702094200