Phosphate content of muscle phosphofructokinase in the genetically diabetic mouse (C57BL/KsJ)

The amount of phosphofructokinase based on total soluble protein in extracts of skeletal muscle from genetically diabetic mice C57BL/KsJ (db/db) was about 30% lower than that of normal controls (db/m). Organic phosphate content of five control animals varied between 0.11 and 0.19 mol/mol protomer. On the other hand, the phosphate content of diabetic mice had a much broader range (0.11 to 0.39) with a mean content for five animals of 0.24 mol/mol enzyme protomer. Partial resolution of high- and low-phosphate forms can be achieved by ion-exchange chromatography. The more highly phosphorylated enzyme is slightly more sensitive to ATP inhibition than the low-phosphate enzyme.