Membrane Transport 2 Flashcards
Give 3 characteristics of the Mitochondrial Genome.
1) It contains no introns or protective histones.
2) It can be damaged through exposure to reactive oxygen.
3) There is no effective DNA repair system (so the mutation frequency is higher).
What is the difference between a strong reducing agent and oxidizing agent?
A strong reducing agent (electron donor) has a negative redox potential.
A strong oxidising agent (electron acceptor) has a positive redox potential.
Name 4 molecules that can transfer electrons
1) Flavins
2) FeS
3) Copper ions
4) Hemes (cytochromes)
Name a molecule that can act as an apoptosis trigger?
Cytochrome C
How much energy is available for electron transfer?
ΔEo` = +1.14V
If ΔG is negative, the reaction is known as being ____?
Exogonic - it will release energy.
If ΔG is positive, the reaction is known as being ____?
Endogonic - it will require an input of energy.
How do you calculate ΔG (the free energy of a reaction)?
ΔG = -nFΔEo`
ATP synthase has two domains. In which domain does ATP hydrolysis and ATP synthesis occur?
ATP hydrolysis and ATP synthesis occurs in the F1 domain.
Where in the mitochondria does 2% of the oxygen that becomes reactive come from?
It comes from complex IV.
How is ATP produced in the inner mitochondrial membrane?
Respiration will lead to the generation of positive charge in the intermembrane space. This will in turn generate a proton motive force that will be used to produce ATP.
Name two inhibitors of the ATP/ADP transporter and how they inhibits the transporter.
Carboxyatracytloside (CATR). It is a plant poison that forms numerous H-bonds with residues in the ADP binding pocket and prevents the binding of ADP.
Sulfhydryl reagents (e.g. MTSES) form covalents bonds with the cysteine residues to block the channel.
What is the major amino acid in ATP/ADP transporters?
Cysteines.
Cysteines can be changed to alanines without affecting its activity.
What kind of transport does the ATP/ADP transporter use?
Secondary active transport - it is driven by a proton motive force.
How many protons are required for ATP synthase to make and transport ATP?
4.3 H+ is required to make and transport ATP.
