Lecture 12-13 Pyruvate dehydrogenase complex (PDC) & Citric acid cycle (CAC)

How do you prepare for CAC ( Citric acid cycle)?

Otherwise called the Krebs cycle

• Pyruvate —- acetyl-CoA by pyruvate dehydrogenase complex (PDC) in the mitochondria 

• It is 8 Steps in the mitochondial matrix

• Succinate dehydrogenase is in the inner mitochondrial membrane 

• Acetyl-CoA converts to 2 CO2

• NADH, FADH2, GTP / ATP generated

• ETC on the inner mitochondrial membrane, electrons transferred to O2 while proton gradient is established and used to synthesize ATP

What does Preperation for CAC look like in the mitochondria? 

● Outermembrane: much more permeable than the innermembrane
● Innermembrane: electron transfer chain and ATP synthase
● Matrix: CAC except one enzyme

Coenzyme A (CoA)? 

• 2 carbon carriers in CAC 

• Contains vitamin B5, pantothenate 

• High energy thioester bond 

What is the pyruvate dehydrogenase complex? 

Pyruvate + CoA + NAD+ → acetyl-CoA + CO2 + NADH + H+