ELECTRON TRANSPORT CHAIN Flashcards
3 stages of oxidative phosphorylation
- acetyl-coa production
- acetyl-coa oxidation
- etc and oxidative phosphorylation
electron donors of ETC
NADH (Complex I)
Succinate (complex II)
ubiquinol (complex III)
electron acceptors of ETC
UBIQUINONE
CYTOCHROME C
OXYGEN
3 types of electron transport
- direct
- transfer as a hydrogen atom
- transfer as hydride ion which holds 2 electrons
4 mobile carriers of electrons
Heme b
Heme c1
Ubiquinol
Cytochrome c
endergonic rxns in ETC (against gradient)
complex I (4 PROTONS)
complex III (4 PROTONS)
complex IV (2 PROTONS)
NADH binds and donates 2 electrons to FMN, FMN passes them one at a time to FeS, FeS puts them on ubiquinone, makes 1 ATP
Complex I
passes electrons from succinate to ubiquinone through FADH2 and FeS, doesn’t make enough energy to make ATP, NOT A PROTON PUMP
Complex II
Transfers 1 electron at a time to ubiquinone to cytochrome c, pumps 4 protons from matrix to intermembrane
Complex III
Proteins with heme as their prosthetic group, water soluble and carries 1 electron at a time
4 N containing rings around Fe
cytochromes
target complex for inhibition, pumps 2 protons from matrix to intermembrane space, most exergonic complex at -110kJ/mol
complex IV
Inhibitor of complex I
riboflavin
inhibitor of complex II
malonate
inhibitor of complex III
antimycin A
inhibitor of complex IV
cyanide, KCN, CO
Multiple complexes associated together to form a “super complex” contains all 4 complexes and 6 molecules of CoQ
respirasome
4 inhibitors of respiratory chain
Rotenone (complex I)
malonate (complex II)
antimycin A (complex III)
cyanide (Complex IV)
Proteins involved in ATP synthesis
adenine nucleotide translocase, ATP synthase, phosphate translocase
what converts energy stored in electrochemical potential to the mechanical energy of ATP synthase rotation into ATP energy
Coupling process
what is the coupling factor?
ATP synthase
which proton channel in atp synthase is embedded in the inner membrane?
Fo
which proton channel in atp synthase has ATPase activity?
F1
How many protons does it take to make 1 ATP in ATP synthase?
4
what blocks ATP synthase?
oligomycin
what blocks ADP/ATP antiporter?
Atractyloside
what are the levels of ATP, ADP, NADH and NAD+ in the RESTING state of ATP production regulation?
ATP-HIGH
ADP-LOW
NADH-HIGH
NAD+-LOW
What are the levels of ATP, ADP, NADH and NAD+ in the ACTIVE state of ATP production regulation?
ATP-LOW
ADP-HIGH
NADH-LOW
NAD+-HIGH
(Its just the opposite of the resting state)
