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Vitamin B6 refers to a group of chemically very similar compounds which can be interconverted in biological systems. Vitamin B6 is part of the vitamin B group, and its active form, Pyridoxal 5'-phosphate (PLP) serves as a cofactor in many enzyme reactions in amino acid, glucose, and lipid metabolism. ==Forms== Several forms (vitamers) of vitamin B6 are known: * Pyridoxine (PN), the form most commonly given as vitamin B6 supplement * Pyridoxine 5'-phosphate (PNP) * Pyridoxal (PL) * Pyridoxal 5'-phosphate (PLP), the metabolically active form (sold as 'P-5-P' vitamin supplement) * Pyridoxamine (PM) * Pyridoxamine 5'-phosphate (PMP) * 4-Pyridoxic acid (PA), the catabolite which is excreted in urine * Pyritinol, a semi-synthetic derivative of pyridoxine, where two pyridoxine moieties are bound by a disulfide bridge. All forms except pyridoxic acid and pyritinol can be interconverted. Absorbed pyridoxamine is converted to PMP by pyridoxal kinase, which is further converted to PLP by pyridoxamine-phosphate transaminase or pyridoxine 5’-phosphate oxidase which also catalyzes the conversion of PNP to PLP. Pyridoxine 5’-phosphate oxidase is dependent on flavin mononucleotide (FMN) as a cofactor which is produced from riboflavin (vitamin B2) i.e. in this biochemical pathway, dietary vitamin B6 cannot be used without vitamin B2. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Vitamin B6」の詳細全文を読む スポンサード リンク
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