The interconversion of glutamic acid and proline.

Oxidation of proline to glutamic acid is presumed to proceed via the intermediate Al-pyrroline-5-carboxylic acid (l-3) and therefore should require the participation of an enzyme system oxidizing the latter compound. We have previously reported the existence of such an enzyme in rat liver mitochondria (4). This communication describes the partial purification and some properties of a pyridine nucleotide requiring enzyme from ox liver which oxidizes Ai-pyrroline-5-carboxylic acid to glutamic acid. Experimental results dealing with enzymic specificity, kinetics, and effects of inhibitors are presented.