Lactate dehydrogenase from cultured Aedes albopictus cells: kinetic and isozyme analysis

L(+) lactate dehydrogenase (LDH) activity from cultured cells of Aedes albopictus was studied as a kinetic model of carbohydrate metabolism. Enzyme kinetics were studied in the forward (lactate as substrate) and reverse (pyruvate as substrate) reactions and the apparent Km values were obtained showing LDH higher affinity for pyruvate. The Hill coefficient values for each substrate were similar and indicate the existence of only one binding site on the enzyme. Isozyme analysis on cellulose-acetate electrophoresis presented a single band of LDH which presumably is of the LDH-5 type. The results obtained contribute to the assumption that Aedes albopictus cells have a predominance of anaerobic metabolism.