| Abstract: | Phosphofructokinase has been purified from Escherichia coli strain K-12 grown in a glucose-limited chemostat, both aerobically and anaerobically. The enzymes migrated together in polyacrylamide gel electrophoresis, had the same subunit size in denaturing (dodecylsulfate) gels (Mr approx. 34000) and the same kinetic characteristics as described earlier for E. coli phosphofructokinase [e.g. Blangy et al. (1968) J. Mol. Biol. 31, 13-35]: a sigmoid curve of velocity vs. fructose 6-phosphate concentration, activation by ADP, and inhibition by phosphoenolpyruvate. Findings [e.g. Doelle (1975) Eur. J. Biochem, 50, 335-342] of quite different enzymes in aerobic and anaerobic cells were not confirmed. |
