4-pyridoxic acid is a methylpyridine that is 2-methylpyridine substituted by a hydroxy group at C-3, a carboxy group at C-4, and a hydroxymethyl group at C-5. It is the catabolic product of vitamin B6 and is excreted in the urine. It has a role as a human metabolite and a mouse metabolite. It is a member of methylpyridines, a hydroxymethylpyridine, a monohydroxypyridine and a vitamin B6. It derives from an isonicotinic acid. It is a conjugate acid of a 4-pyridoxate.
https://pubchem.ncbi.nlm.nih.gov/compound/4-Pyridoxic-acid
Biotechnological Production
4-Pyridoxic acid is an inactive metabolite of pyridoxine.It is formed from pyridoxine via pyridoxal 5'-phosphate and pyridoxal intermediates by pyridoxine kinase or pyridoxamine phosphate oxidase, as well as pyridoxine-5'-phosphate oxidase, aldehyde dehydrogenase, or aldehyde oxidase.
4-Pyridoxic acid is the catabolic product of vitamin B6 (also known as pyridoxine, pyridoxal and pyradoxamine) which is excreted in the urine. Urinary levels of 4-pyridoxic acid are lower in females than in males and will be reduced in persons with riboflavin deficiency. 4-Pyridoxic acid is formed by the action of aldehyde oxidase I (an endogenous enzyme) and by microbial enzymes (pyridoxal 4-dehydrogenase), an NAD-dependent aldehyde dehydrogenase. 4-pyridoxic acid can be further broken down by the gut microflora via 4-pyridoxic acid dehydrogenase. This enzyme catalyzes the four electron oxidation of 4-pyridoxic acid to 3-hydroxy-2-methylpyridine-4,5-dicarboxylate, using nicotinamide adenine dinucleotide as a cofactor.
4-Pyridoxic acid is a catabolite of vitamin B6. It has been used as a standard in the clinical spectrometric analysis of metabolites.
4-Pyridoxic Acid, a catabolite of vitamin B6 (P991735), is a water-soluble B-group vitamin that can be used as a urinary diagnostic biomarker for determining the nutritional status of these vitamins.
ChEBI: 4-pyridoxic acid is a methylpyridine that is 2-methylpyridine substituted by a hydroxy group at C-3, a carboxy group at C-4, and a hydroxymethyl group at C-5. It is the catabolic product of vitamin B6 and is excreted in the urine. It has a role as a mouse metabolite and a human urinary metabolite. It is a member of methylpyridines, a hydroxymethylpyridine, a monohydroxypyridine and a vitamin B6. It is functionally related to an isonicotinic acid. It is a conjugate acid of a 4-pyridoxate.
This oxidized derivative (FW = 171.15 g/mol) of pyridoxal is the chief catabolic product of pyridoxine, pyridoxal, and pyridoxamine degradation; it can be isolated from human urine. The carboxyl group has a pKa value of 5.50 while the phenolic OH has a value of 9.75. 4-Pyridoxic acid has a blue fluorescence which is maximal between pH 3 and 4. Heating 4-pyridoxic acid in 0.5 N acid will convert the metabolite to its lactone, which has an even stronger fluorescence. Target(s): dextransucrase; glucose dehydrogenase; pyridoxal dehydrogenase; and pyridoxaminephosphate oxidase.
