Answer to Question #210833 in Biochemistry for Maria

Question

I learnt that all the enzymes of the Krebs cycle are inside the mitochondrial matrix except for the succinate dehydrogenase . can u please explain me why? Thank you so much

PS U can give me a complicated answer if it is needed; i will search for all the information to understand it

Answer 1

Majorly, all enzymes of TCA cycle are present in mitochondrial matrix except succinate dehydrogenase. 

Notably, succinate dehydrogenase is tightly bound to the inner mitochondrial membrane in eukaryotes and  to the plasma membrane in prokaryotes. It has three different iron-sulfur clusters and one covalently bound FAD. Before entering ETS in mitochondria, electrons pass from succinate through the FAD and iron-sulfur centers.