8: ETC and Oxidative Phosphorylation Flashcards
Oxidative phosphorylation
the enzymatic synthesis of ATP coupled to the transfer of electrons to molecular oxygen
What is complex I?
NADH dehydrogenase
What is complex II?
succinate dehydrogenase
What is complex III?
cytochrome bc1
What is complex IV?
cytochrome aa3
What molecule does complex 1 take electrons from?
NADH, forming NAD+
Which complex doesn’t span the membrane and cannot pump hydrogens?
complex II
Ubiquinone
the point of entry for electrons derived from complex I, cytosol, fatty acid oxidation, and succinate oxidation
What molecule does complex II take electrons from?
FAD
Where does complex I send its electrons?
coenzyme Q
Where does complex II send its electrons?
coenzyme Q
Where does complex III send its electrons?
cytochrome c
Where does complex IV send its electrons?
to oxygen to create water
What drug inhibits complex I?
rotenone (pesticide, insecticide)
What drug inhibits complex III?
antimycin A (fish poison)
What drug inhibits complex I?
What drug inhibits complex IV?
potassium cyanide and carbon monoxide
Where is the majority of ATP made?
ATP synthase
What is the most damaging free radical?
hydroxyl (OH)
How many electrons does it take to reduce O2 to H2O?
4
What reactive oxygen species is a byproduct of coenzyme Q?
O2-
What is the group of enzymes that metabolize drugs in the liver?
cytochrome P450
Glutathione
an antioxidant found in plants, animals, fungi, and some bacteria that is made up of glutamate, cysteine, and glycine
What is the results of tylenol overdose?
depletion of glutathione reserves and hemolysis of RBCs (hemolytic anemia)
What is the treatment for Tylenol overdose?
NAC (N-acetylcysteine) increases glutathione levels by supplying cysteine
What subunit of ATP synthase generates the most ATP?
F1
