Malate Dehydrogenase in Dental Pulp

Abstract

We partially purified malate dehydrogenase (EC.1.1.1.37; MDH) from the dental pulp of pigs. The specific activity of MDH in the crude extract was 0.039 units/mg of protein, and was increased slightly to 0.46 units/mg of protein with ammonium sulfate fractionation and Sepadex G-150 column chromatography. The optimal pH was determined to be pH 9.0 for the oxidation of L-malate and pH 7.0 for the reduction of oxalacetate. The Km values were determined to be 7.4×10-5M,9.1×10-5M,7.7×10-5, Mand 7.9×10-5 M fbr L-malate, NAD+, oxalacetate, and NADH.