lecture 11 - krebs cycle

Question 1

what allows pyruvate and NADH to get into the mitochondria

Answer 1

transporters

Question 2

when in the mitochondria what enzyme acts on pyruvate

Answer 2

pyruvate dehydrogenase

Question 3

what enzymes make up PDH

Answer 3

-pyruvate decarboxylase
-dihydrolipoyl transacetylase
-dihydrolipoyl dehydrogenase

Question 4

what does PDH use as a cofactor

Answer 4

vitamin B1

Question 5

what does PDH do

Answer 5

• What it does is it catalyses the irreversible oxidative decarboxylation of pyruvate
  This is important because this is the gatekeeper into the TCA cycle, you are using glucose to generate energy in the TCA cycle, you don’t want to lose any acetyl coA that you make going backwards and then forming some other compounds baclk up the chain, you want it to feed into the TCA cycle, it is kind of like a checkpoint