Malonic Acid Biosynthesis in Bush Bean Roots. II. Purification and Properties of Enzyme Catalyzing Oxidative Decarboxylation of Oxaloacetate

In the preceding paper (4) evidence was presented that a soluble enzyme preparation from bush bean roots was capable of forming malonate from oxaloacetate (OAA). Carbons 3 and 4 of OAA were equally incorporated into malonate, suggesting that OAA undergoes an a-decarboxylation. In the presence of the crude enzyme preparation, Mn+2 appeared to be the only supplemental cofactor required for malonate formation. The experiments reported in the present paper describe the partial purification and characterization of the enzyme(s) catalyzing the conversion of OAA to malonate.