q8 Flashcards
where does ets occur
mitochondrial membrane
what is the route for NADH
NADH –> comp1 –> Q –> comp3 –> cyt c –> comp4 –> O2
what is the route for FADH2
FADH2 –> comp2 –> QH2 –> comp3 –> cyt c –> comp4 –> O2
how many H+ are pumped during NADH? during FADH2?
10
6
what inhibit ets
rotenone, hydrogen cyanide, CO, and antimycin A
describe comps 1,3,4
multi-subunits that move proton across IMM
describe coenzyme q
small hydrophobic e- carrier
comp1/2–>comp3
describe cytochrome c
small water soluble protein in intermembrane
1 e-
comp 3&4
name: comp 1
comp 2
comp 3
comp 4
ubiquinone oxidoreductase
succinate dehydrogenase
cytochrome c oxidoreductase
cytochrome c oxidase
describe redox centers
bound to proteins in ETS
how many protons does NADH ubiquinone oxidoreductase pump
4
what is the net rxn for NADH ubiquinone oxidoreductase
NADH + Q + 5H+n —> QH2 + 4H+p
what is the net rxn for succinate dehydrogenase
FADH2 + Q —> FAD + QH2
how many protons does ubiquinone cytochrome c oxidoreductase pump
4
how many protons does ubiquinone cytochrome c oxidoreductase pump
4
what is the net rxn of ubiquinone cytochrome c oxidoreductase
QH2 + 2H+n + 2 cytochrome c —> Q + 4H+p + 2 cytochrome c
when does the q cycle occur
in comp3
what are the 4 steps of the q cycle
- oxidation at QH2
- oxidized Q to Qn
- new QH2 binds to Qp
- second e- reduces semiquinone
describe cytochrome c
comp3 —> comp4
small and associated with cytosolic side of IMM
highly conserved
describe cytochrome c oxidase
homodiamer
pumps 2H+ into intermembrane space
how many protons are brought in with NADH?
with FADH2?
10
6
what are the 3 unites for ATP synthase
rotor
catalytic headpiece
stater
what is the F1 component
the catalytic head
binds ADP and Pi
releases ATP
no rotation
y subunit will cause rotation and conformational change
describe the stater
stationary
protons are able to enter and exit c-ring
attaches F0 to F1
describe F0
2 proton half channels embedded in the membrane
c-ring rotates with proton flow with 10 helices
describe half channels
Hp+ enters via Hp+ channels
Hp+ protonates asp59
~36 rotations of c-ring
protonated asp59 released H+ to n-side through Hn+ channel
describe ATP/ADP translocase
imports 1 ADP to matrix and exports 1 ATP to inter membrane state
describe phosphate translocase
channel proteins
symports Pi and H+
antiports Pi and OH-
how many H produce 1ATP
4
describe cytosolic DNA
created in glycolysis
e- can only cross the membrane via shuttle systems
important #
important numbers
important numbers
net rxns
describe malate-aspartate shuttle
liver/heart/kidney/etc
produces 10H+ or 2.5 ATp
describe glycerol-3-phosphate shuttle
muscle and skeletal tissue
NADH reduces FAD
faster and more simple
produces 6H+ or 1.5 ATP
what happens if energy charge is high
processes will be inhibited
most reactants are _________ and most products are ________
activators
inhibitors
what activates many pathways
ADP and Pi
what does 2,4-dnp do
transports H+ but does not synthesize ATP
uncoupled H+ circuit from ATP synthase
what can inhibit complex IV
cyanide
what does oligomycin block
ATP synthase
