Consider the hypothetical experiment described below and apply your knowledge of
ID: 41833 • Letter: C
Question
Consider the hypothetical experiment described below and apply your knowledge of inhibitors of electron transport and oxidative phosphorylation. There may be more than one right answer, but there are definitely some that are not right. a. You have coupled, functioning mitochondria and provide NADH and O2. If only ATP synthase is Inhibited (this is not an uncoupler, instead proton movement through ATP synthase is prevented) would the spectral data of the cytochromes in intact mitochondria indicate that they were all reduced, all oxidized or somewhere in between? Explain your rationale. b. Would the system be any different if an artificial electron acceptor was used at Complex III? Explain.Explanation / Answer
a. The spectral data would show the cytochromes as reduced. Since an uncoupler is not present but only the inhibition of ATP synthase occurs,this indicates that even with the high proton concentration, ATP synthesis does not occur.The rest of the events occur normally.
b. If an artificial electron acceptor was used with inhibition of ATP synthase the situation wont change. The electron transport will occur but proton translocation will not occur.