How Does Altering pH Impact ATP Synthesis in the Respiratory Chain?

[jasper10]

Homework Statement

What would happen to the level of ATP synthesis in the respiratory chain if you make the intermembranal space more acidic more acidic? What if it were made more basic?

Homework Equations

The Attempt at a Solution

ATP synthesis is triggered by chemiosmosis - the flow of H+ protons down their concentration gradient, through ATPase. ATPase uses this motion to synthesise ATP. Adding acid means adding more protons. Does this mean that ATP production will increase? Could acidic conditions damage the chain?

 

[Ygggdrasil]

Is that the exact statement of the question? As posted the question makes no sense. Membranes (which are not aqueous) do not have a pH. Is the question asking what happens if you make the mitochondrial matrix more acidic/basic?

As for the question, you need to consider in what direction the H⁺ gradient is setup. Do protons flow from the mitochondrial matrix to the intermembrane space or vice versa? How would adding protons to each side of the mitochondrial inner membrane affect the concentration gradient?

 

[jasper10]

Is the question asking what happens if you make the mitochondrial matrix more acidic/basic?

yes: What would happen to the level of ATP synthesis in the respiratory chain if you make the intermembranal space more acidic more acidic?

Do protons flow from the mitochondrial matrix to the intermembrane space or vice versa?

Yes in respiration the protons flow from the mitochondrial matrix to the intermembranal space. So making it more acidic would increase the concentration gradient: this is only in the short term run. In the long term run, wouldn't the proteins be denatured for example the cytochromes? Why do extreme pH's denature enzymes and proteins? thx