Regulation of glycolysis and gluconeogenesis

Regulation of PFK-1 The effect of ATP on the allosteric enzyme PFK-1 is shown below. For a given concentration of fructose 6 -phosphate, the PFK- 1 activity increases with increasing concentrations of ATP, but a point is reached beyond which increasing the concentration of ATP inhibits the enzyme. (FIGURE CAN'T COPY) (a) Explain how ATP can be both a substrate and an inhibitor of PFK-1. How is the enzyme regulated by ATP? (b) In what ways is glycolysis regulated by ATP levels? (c) The inhibition