Two types of Pyruvate Kinase in Mucor rouxii

Extracts of mycelium of Mucor rouxii have been shown to contain two forms of pyruvate kinase named Type I and II. They can be separated by DEAE‐cellulose chromatography and by electrophoresis in polyacrylamide gel. Extracts from ungerminated sporangiospores or yeast‐like cells contained only the Type I form. Pyruvate kinase Type II appears during aerobic germination of spores or during conversion of yeast‐like cells to mycelium. Both pyruvate kinases are similar in their molecular weight, pH range of activity, Km with respect to substrates and their response to activators (Mn++ and fructose 1,6‐diphosphate).