The enzyme 3-hydroxy-2-methylpyridine-4,5-dicarboxylate 4-decarboxylase () catalyzes the chemical reaction
This enzyme belongs to the family of lyases, specifically the carboxy-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is 3-hydroxy-2-methylpyridine-4,5-dicarboxylate 4-carboxy-lyase (3-hydroxy-2-methylpyridine-5-carboxylate-forming). This enzyme is also called 3-hydroxy-2-methylpyridine-4,5-dicarboxylate 4-carboxy-lyase. This enzyme participates in vitamin B<sub>6</sub> metabolism.