1.1.1.203 evolution the enzyme belongs to the short-chain dehydrogenase/reductase (SDR) superfamily -, 740959 1.1.1.203 evolution UDH is a member of the short-chain dehydrogenase/reductase(SDR) superfamily, whose members typically contain a single domain having a highly variable C-terminal substrate binding site, reflecting the diverse nature of SDR substrates and attendant substrate binding site structures, and a conserved N-terminal cofactor binding site -, 740393 1.1.1.203 metabolism the enzyme is proposed to be part of the salvage pathway in ascorbate production as galacturonate acid reductase, GalUR, EC 1.1.1.203, converting D-galacturonate to L-galactono-1,4-lactone, ascorbate biosynthesis and recycling pathways in plants, overview 743517 1.1.1.203 metabolism uronate dehydrogenases catalyse the initial step in an oxidative pathway -, 740959 1.1.1.203 metabolism uronate dehydrogenases catalyses the initial step in an oxidative pathway 740959 1.1.1.203 physiological function ascorbate accumulation is affected mainly by biosynthesis rather than recycling in radish root, and the L-galactose pathway may be the major biosynthetic route of ascorbate, and moreover, the salvage pathway may also contribute to ascorbate accumulation. Ascorbate level regulation involves the D-galacturonate reductase and GDP-D-mannose diphosphorylase 743517