10/6 TCA Cycle

Question 1

vitamins req’d for PDH and effect of deficiency

Answer 1

thiamine, lipoic acid, riboflavin, niacin

decreased ATP

Question 2

vitamin req’d for pyruvate carboxylase and effect of deficiency

Answer 2

biotin

lactic acidosis

Question 3

5 points of e- removal in PDC and TCA cycle

Answer 3

1. pyruvate dehydrogenase (NADH)
2. isocitrate dehydrogenase (NADH)
3. a-ketoglutarate dehydrogenase (NADH)
4. succinate dehydrogenase (FADH2)
5. malate dehydrogenase (NADH)

Question 4

glycoxylate cycle

Answer 4

2 enzymes bypass decarboxylation

isocitrate converted to glycoxylate and succinate by [isocitrate lyase]

glycoxylate +A-CoA converted to malate by [malate synthetase]

Question 5

why is isocitrate lyase a good drug target

Answer 5

inhibition prevents production of sugar

good for fungi and mycobacteria (and TB?)

Question 6

5 cofactors of PDH complex

Answer 6

TPP
FAD
CoA
NAD
Lipoate

Question 7

role of TPP in PDH complex

Answer 7

thiamine pyrophosphate destabilizes bond w/in pyruvate

Question 8

role of FAD in PDH complex

Answer 8

flavin adenine dinucleotide is an e- carrier

Question 9

role of CoA in PDH complex

Answer 9

coenzyme-A is an acyl carrier, activates things for group transfer

Question 10

role ofNAD in PDH complex

Answer 10

nicotinamide adenine dinucleotide is an e- carrier

Question 11

role of lipoate in PDH complex

Answer 11

lipoate is both an e- carrier and an acyl carrier (redox rnxs)