ETC and oxidative phosphorylation Flashcards
What is the label given to exergonic reactions in metabolism?
Catabolic
What is the label given to endergonic reactions in metabolism?
Anabolic
What makes a reaction oxidative?
Gain of oxygen
Loss of electrons
Loss of hydrogen
What makes a reaction reductive?
Loss of oxygen
Gain of electrons
Gain of hydrogen
What are the three molecules that can move freely across the IMM?
H2O
O2
CO2
What are the sources of FADH2 used in the ETC?
Succinate dehydrogenase in TCA cycle
Acyl CoA dehydrogenase in beta-oxidation
What are the sources of NADH used in the ETC?
Glyceraldehyde 3P DH in glycolysis
PDH in glycolysis
Isocitrate DH in TCA cycle
Alpha-ketoglutarate DH in TCA cycle
Malate DH in TCA cycle
Beta-hydroxyacyl CoA DH in beta-oxidation
What are the two shuttles to bring NADH into the mitochondria?
Malate-aspartate shuttle
Glycerol 3P shuttle
In which cells of the body is the malate-aspartate shuttle found?
Liver
Heart muscles
In which cells of the body is the glycerol 3P shuttle mainly used?
Brain
Skeletal muscle
What are the mobile carriers used in the ETC?
Ubiquinone/coenzyme Q
Cytochrome C
What are the two minerals found in the cytochromes used in ETC?
Iron in all
Copper in a and a3
What are the prosthetic groups of complex I of the ETC?
FMN
6-7 Fe-S clusters
What is the basic function of complex I of the ETC?
Change NADH to NAD giving the electrons to CoQ
What are the prosthetic groups of complex II of the ETC?
FAD
Fe-S
What is the basic function of complex II of the ETC?
Transfers electrons from FADH2 to CoQ
What is the enzyme name of complex I of the ETC?
NADH CoQ reductase/NADH dehydrogenase
What is the enzyme name of complex II of the ETC?
Succinate CoQ reductase
What is the enzyme name of the Complex III of the ETC?
Cytochrome reductase
What is the general function of complex III of the ETC?
Accepts electrons from CoQ and transfers them to cytochrome C
What are the prosthetic groups of complex III?
Cytochrome B
Fe-S
Cytochrome C1
What is the enzyme name of complex IV of the ETC?
Cytochrome oxidase
What is the general function of complex IV of the ETC?
Accept electrons from cytochrome C and transfer them to O2 to make H2O
What are the prosthetic groups of complex IV?
Cytochrome A with copper
Cytochrome A3 with copper
What are the two subunits of ATP synthase on IMM?
Fo - proton channel
F1 - catalyzes ATP synthesis
How with increased levels of ADP, Pi, NADH, and FADH2 affect the rate of ETC?
They will increase the rate of ETC
How will hypoxia affect the rate of the ETC?
Decrease the rate
What are the site specific inhibitors of complex I of the ETC?
Amobarbital
Rotenone
Piericidin A
What are the site specific inhibitors of complex II of the ETC?
TTFA - tenoyltrifluoro acetone
Carboxin
What are the site specific inhibitors of complex III of the ETC?
Antimyxin A
BAL - British antilewisite
What are the site specific inhibitors of complex IV of the ETC?
Cyanide
Carbon monoxide
Sodium azide
Hydrogen sulfide
What are inhibitors of oxidative phosphorylation?
Oligomycin
Uncouplers
Atractyloside
What is the action of uncouplers?
Leakage of protons back into the mitochondrial matrix acting as ionophores
What is the result of the action of uncouplers?
Abolition of the electrochemical gradient
What are some examples of uncouplers?
2,4 dinitrophenol
Dinitrocresol
High dose of aspirin
High dose of salicylates
UCP in brown adipose tissue
How does oligomycin inhibit oxidative phosphorylation?
Binds to Fo region of ATP synthase and closes the proton channel
How does atractyloside inhibit oxidative phosphorylation?
Inhibits ATP transport across IMM
