Which of the following is NOT a stimulator of glycolysis?

Citrate is known to inhibit glycolysis, making it the correct choice as the option that is not a stimulator of this metabolic pathway. It serves as a vital signaling molecule in cellular metabolism. When citrate levels are high, it indicates that the energy supply within the cell is sufficient, leading to a reduction in the flux through glycolysis. High concentrations of citrate promote the conversion of pyruvate to glucose via gluconeogenesis, as opposed to continuing down the glycolytic pathway.

On the other hand, fructose 2,6-bisphosphate acts as a powerful activator of glycolysis by enhancing the activity of phosphofructokinase-1 (PFK-1), a key regulating enzyme in the pathway. AMP also stimulates glycolysis; it serves as a signal of low energy status in the cell, activating PFK-1 to promote energy production through glycolysis. Insulin has an indirect stimulating effect on glycolysis as it promotes glucose uptake in cells and increases the expression of glycolysis-related enzymes through its action on insulin receptor signaling pathways.