Forms of Cytosolic Nicotinamide Adenine. Dinucleotide-linked Glycerol-3-phosphate Dehydrogenase in Normal and Neoplastic Mouse Tissues

L-Glycerol-3-phosphate: NAD-2-oxidoreductase (EC 1.1.1.8) in unfractionated homogenates and in preparations partially purified by affinity chromatography was examined for potential differences among forms from normal and neoplastic mouse tissues. Polyacrylamide gel isoelectric focusing, heat inactivation, and immunoelectrophoresis with goat anti-mouse liver enzyme as antiserum applied to separate and mixed preparations showed that the major form of the enzyme, regardless of the initial specific activity, was indistinguishable by these criteria in all normal tissues examined including skeletal muscle, liver, kidney, brain, spleen, and heart as well as in BW7756 hepatoma. Several less cationic, heat-labile forms specific for certain tissues were also observed. Two strongly anionic forms of the enzyme appeared in early stages of fetal development and accounted for the major proportion of the enzyme activity in L1210 leukemia. One of these forms was observed in trace amounts in adult brain, kidney, and heart tissues. L1210 leukemia glycerol-3-phosphate dehydrogenase had electrophoretic, immunological, and heat stability properties different from the major form of the enzyme found in all normal tissues. Analysis of forms of the enzyme in a spectrum of tumors (including the ascites and solid forms of L1210 leukemia, Sarcoma 180, Ad755 adenocarcinoma, and H129 hepatoma; the solid tumors B16 melanoma and BW7756 hepatoma; and the ascites form of the Ehrlich tumor as well as a long-passage suspension culture of P388 leukemia in log-and plateau-phase growth) suggested that the anionic forms may be characteristic of rapidly dividing cells in populations with high growth fractions.