Glycolysis — Rate-Limiting + Regulation

Rate-limiting enzyme: PHOSPHOFRUCTOKINASE-1 (PFK-1) PFK-1 regulation: • Activated by: AMP, fructose-2,6-bisphosphate • Inhibited by: ATP, citrate Other key enzymes: • Hexokinase / Glucokinase — first step (glucose → G6P) • Pyruvate kinase — last step (PEP → pyruvate) Net yield (anaerobic): 2 ATP, 2 NADH, 2 pyruvate per glucose Net yield (aerobic, full TCA + ETC): ~30–32 ATP Enzymes deficient in genetic disease: • Pyruvate kinase deficiency → haemolytic anaemia • Hexokinase deficiency → similar