5-formyl-3-hydroxy-2-methylpyridine-4-carboxylate + NAD(+) + H2O <=> 5-hydroxy-6-methylpyridine-3,4-dicarboxylate + NADH + 2 H(+)
5-formyl-3-hydroxy-2-methylpyridine-4-carboxylate + nad(+) + h2o <=> 5-hydroxy-6-methylpyridine-3,4-dicarboxylate + nadh + 2 h(+)