Biochemistry Flashcards
what are the five required cofactors for pyruvate dehydrogenase complex?
NAD+, lipoic acid, FAD, CoA, and thiamine pyrophosphate
why do we use thiamine pyrophosphate in alpha-decarboxylations?
because it has a thiazole ring where a reactive carbon can be made
what are the three components of pyruvate dehydrogenase complex?
E1, E2, E3 (E2 on inside, E3 and E1 on outside)
what is the E1 part of PDC?
pyruvate dehydrogenase with TPP
what is the E2 part of PDC?
transacetylases (with lipoic acid)
what is the E3 part of PDC?
dihydrolipoyl dehydrogenase (contains FAD)
what are possible symptoms of thiamine deficiency?
polyneuropathy, paresthesia (tingling/prickling), paresis (paralysis/weakness), psychiatric confabulation, possible edema (wet beri beri - flabby dilated heart)
what Leigh syndrome?
neurodegenerative disorder due to build-up of lactic acid in brain - it is a mitochondrial disorder with poor functioning oxidative phosphorylation
what are the symptoms of Leigh syndrome?
weakness, hypotonia, ataxia, spasticity, respiratory disease, dyspnea, opthalmoplegia, optic atrophy; ultimately lethal
*can result from deficient pyruvate carboxylase
what are the sources of Acetyl CoA?
fatty acids, pyruvate, amino acids, ketone bodies, acetate
**Fargo Put Away Keys Again
how much ATP is generated from one NADH?
2.5 ATP
how much ATP is generated from one FADH2?
1.5ATP
how much ATP is generated from one round of the TCA cycle?
10 ATP
how much ATP is generated from the TCA cycle per glucose?
20 ATP
which enzyme is a key regulator of the TCA cycle and what inhibits and activates it?
isocitrate dehydrogenase
it is activated by ADP and inhibited by NADH
