Mitochondrial Bioenergetics Flashcards
Explain pyruvate dehydrogenase phosphatase (PDP)…
Dephosphorylates/Activates PDC
*Mg dependent
Explain pyruvate dehydrogenase kinase (PDK)…
Phosphorylates/Inactivates PDC
What are the cofactors of the subunits of the PDC?
E1 = TPP (B1) E2 = Lipoic acid E3 = NAD+, FAD
Explain citrate synthetase…
Oxaloacetate + Acetyl-CoA –> citrate (TCA cycle)
Explain aconitase…
Citrate –> isocitrate (TCA cycle)
Explain isocitrate dehydrogenase…
Isocitrate –> alpha-KG (TCA cycle)
- Rate limiting step
- produces NADH
Explain alpha-KG dehydrogenase…
Alpha-KG –> succinyl-CoA (TCA cycle)
*produces NADH
What are the amino acid derivatives of the major TCA cycle intermediates? Pyruvate, acetyl-CoA, alpha-KG, succinyl-CoA, fumarate, oxaloacetate
Pyruvate = Cys, Ala, Ser Acetyl-CoA = Leu Alpha-KG = Glu (from Gln, His, Arg, Pro) Succinyl-CoA = Ile, Val, Met, Thr Fumarate = Tyr (from Phe) Oxaloacetate = Asp (from Asn)
What are the 3 disorders of the TCA cycle talked about on the slides? What do they cause?
2-oxoglutaric acid aciduria - severe neuro problems in infants.
Fumarase deficiency - increased urinary excretion of fumarate.
Succinyl-CoA synthetase deficiency - hypotonia, dystonia, muscle atrophy
What inhibits complex I of the ETC?
Amytal, rotenone, myxothiazol, piercidin A
What inhibits complex II of the ETC?
Malonate
What inhibits complex III of the ETC?
Antimycin
What inhibits complex IV of the ETC?
Cyanide, CO, H2S
What inhibits complex V of the ETC?
Oligomycin
When the ATP:ADP ratio is high, what happens to the ATP synthase?
Decrease ATP production
