Chapter 21 - The Proton Motive Force Flashcards
proton-motive force
gradient where energy from e- transfer is conserved
What provides the necessary energy for ATP synthesis?
the flow of protons down their electrochemical gradient
ATP synthase
catalyzes the formation ATP from ADP and pi
Where does ATP synthase get the energy it needs for the formation of ATP?
energy is derived from the flow of protons from the P side to the N side
Where is ATP synthase found?
in the inner membrane
What are the 2 functional domains of ATP synthase?
F0 and F1
F0
pore that stands the entire membrane
-protons leak back into the matrix through F0 pore
F1
spherical head on which phosphorylation of ADP occurs
-alternating a and B subunits
B-ATP –>
B-empty (releases ATP)
B-empty –>
B-ADP (can loosely bind ADP + Pi)
B-ADP –>
B-ATP
Glycolysis generates __ NADH in cytosol.
2
Inner mitochondrial membrane is ___________ to NADH.
impermeable
NADH dehydrogenase (Complex I) can only utilize NADH in the _______.
matrix
2 shuttles that transport reducing equivalents to mitochondrial matrix?
Malate-aspartate shuttle and Glycerol-3-P shuttle
malate-aspartate shuttle
2.5ATP/NADH –> liver/kidney/heart
glycerol-3-P shuttle
1.5 ATP/NADP –> skeletal muscle/brain
Inner mitochondrial membrane is impermeable to ______ molecules.
charged: ADP(-3), Pi(-1), ATP(-4)
adenine nucleotide translocase
an anti porter that couples the entry of ADP into the matrix and the exit of ATP from it
phosphate translocase
symporter
Compounds that inhibit electron transfer
- rotenone amytal
- antimycin A
- CN- and CO
Target of rotenone amytal
prevent e- transfer from Complex I to ubiquinone
Target of antimycin A
black e- transfer from cyt b to cyt c1 of complex III
Target if CN- and CO
inhibits cyt oxidase of Complex IV
Compound that inhibits ATP synthase
oligomycin
target of oligomycin
inhibits F0
Compound that inhibits ATP-ADP exchange
Bongkrekic acid (an antibiotic from mold Atracetyloside)
Target of Bongkrekic acid
inhibits adenine nucleotide translocase
Production of heat, instead of ATP in brown fat can be experienced by…
newborn humans and hibernating rodents
Thermogenin (UCP-1)
uncoupling protein; generates heat by permitting the influx of protons into the mitochondria without the synthesis of ATP
