Question

An inhibitor compound is being tested for its effect on the electron transport chain. The drug completely blocks complex III. Calculate the ATP yield from glucose when this drug is used. Make sure to show all your work for full credit.

Answer 1

ANSWER : According to the question , a drug completely inhibits the complex III of the electron transport chain. During electron transport chain , the driving force behind the proper ATP synthesis is the Proton motive force, which essentially happens due to the transportation of H+ ions in the inter-membranal space,during the functioning of Electron transport chain. So as a result a total of 6 protons would have transported to the the inter-mebranal space, this eventually leads to creation of proton-gradient. However the aforementioned drug in the question will block the complex III totally, leading to no proton transport as well as no proton motive force development. Therefore there will be no proton -gradient be created and hence will result in no ATP synthesis. So the drug will block any ATP synthesis.