Test 1 mechanisms

Question 1

Pyruvate Dehydrogenase Mechanism

Answer 1

1) Pyruvate is decarboxylated at the E1 site forming hydroxyethyl-TPP
2) E2 uses its lipoamide arm to extend into E1, and E1 catalyzes transfer of acetyl group to the lipoamide
3) E2 arm enters the E2 active site, and acetyl group is transferred to CoA, and Acetyl-CoA is released
4) The reduced lipoamide then swings to E3 active site where it is oxidized by coenzyme FAD-lipoamide is ready to begin another
5) Final produce NADH is produce with he reoxidaiton of FADH2