title: PLP catabolism: identification of the 4-pyridoxic acid dehydrogenase gene in Mesorhizobium loti MAFF303099.
abstract: The function of the mlr6793 gene from Mesorhizobium loti MAFF303099 has been identified. This gene encodes 4-pyridoxic acid dehydrogenase, an enzyme involved in the catabolism of PLP (Vitamin B6). This enzyme was overexpressed in Escherichia coli and characterized. 4-Pyridoxic acid dehydrogenase is a 33kDa protein that catalyzes the four electron oxidation of 4-pyridoxic acid to 3-hydroxy-2-methylpyridine-4,5-dicarboxylate, using nicotinamide adenine dinucleotide as a cofactor. The k cat for NADH production is 0.01s(-1). The KM values for 4-pyridoxic acid and NAD are 5.8 and 6.6microM, respectively.
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Tathagata
authors.initials: T
authors.lastname: Mukherjee
authors.forename: Cynthia
authors.initials: C
authors.lastname: Kinsland
authors.forename: Tadhg P
authors.initials: TP
authors.lastname: Begley
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics*; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D011736:Pyridoxine / Q000378:metabolism*; D012230:Rhizobiaceae / Q000201:enzymology* / Q000235:genetics
chemical_list: D000429:Alcohol Oxidoreductases; C038807:4-pyridoxic acid dehydrogenase; D011736:Pyridoxine