Question

Hypothesize would you think would happen to mammalian cells that were treated with a drug that inhibits the proton pumps of the electron transport chain? What exactly would happen in these cells?

Answer 1

If ATP synthase (proton pump) is blocked the protons that were pumped into intermembrane space from cytosol of mitochondria will not come back in mitochondrial matrix. This will decrease the protons in mitochondrial matrix. When proton concentration is very low in matrix the energy required to pump protons from matrix to intermembrane space against the concentration gradient would be high. The energy released by the movement of electrons would be enough to pump the protons from mitochondria matrix to intermembrane space and the ETC will stop.

So the aerobic respiration of cells will be blocked and the only way to produces energy would be fermentation which include glycolysis. The consumption of glucose will increase to compensate the energy demand.