Question

An enzyme absent in mitochondrial ETS is

• A. FeS protease
• B. Glucose 6-phosphate dehydrogenase
• C. NADH dehydrogenase
• D. Cytochrome c-oxidase

Answer 1

The correct option is B Glucose 6-phosphate dehydrogenase

ETS in mitochondria is the final stage of cellular respiration in which each oxidative step involves release of a pair of hydrogen atoms which dissociates into 2H+ and 2e-. ETS is composed of cytochromes, coenzymes and other enzymes. Glucose 6-phosphate dehydrogenase is not present in ETS. It is involved in pentose phosphate pathway in which glucose 6-phosphate is a substrate. FeS protease, NADH dehydrogenase and cytochrome c-oxidase are found in ETS.

So the answer is 'Glucose 6-phosphate dehydrogenase'.