1. Pyruvate Oxidation Pyruvate dehydrogenase complex

2. Aerobic Fate of Pyruvate: Overview

3. Mitochondria: Site of Oxidations

4. Pyruvate Oxidation to Acetyl-CoA

5. Pyruvate Dehydrogenase Complex l Complex enzyme – 60 polypeptides of 3 kinds l In mitocondrion matrix l Regulated – Inhibited by NADH and GTP – Stimulated by insulin

6. Pyruvate Dehydrogenase Complex l Three enzymes and 5 coenzymes Total MW: 4.5 x 10 6 ! Also present: regulatory protein kinase, phosphatase

7. Lipoic Acid: Acyl- and Redox Carrier

8. Thiamine Pyrophosphate (TPP)

9. Pyruvate Dehydrogenase Mechanism

17. PDH: The Overall Reaction l Acetyl-CoA enter Krebs cycle l NADH passes e – to O 2

18.  -Ketoglutarate Dehydrogenase Complex ∆Gº= –33.5 kJ/mol

19.  -Ketoglutarate Dehydrogenase Complex l Cofactors: FAD, NAD +, lipoate, TPP, CoASH l Mechanism  PDH complex