Redox reactions/ Aerobic metabolism part 1 Flashcards
What is an obligate anaerobe?
Only grows in absence of oxygen
What is an aerotolerant anaerobe?
Use anaerobic metabolism. Possess detoxifying enzymes and ROS.
What is a facultative aerobe?
Can use O2 when available
What is an obligate aerobe?
Must use O2 for energy production
What are the 3 processes in aerobic metabolism?
Citric acid cycle, electron transport chain, oxidative phosphorylation
What are the important intermediates in aerobic metabolism?
NADH, FADH2
What is a redox reaction?
Reaction where electrons are transferred between species.
Electron acceptor = reduced/oxidizing agent
Electron donor = oxidized/reducing agent
In biological reactions, this is usually done through H+ transfer
What is reduction potential?
The tendency of substance to
gain electrons is called Reduction Potential.
What is standard reduction potential?
Standard Reduction Potential is the Reduction Potential of a substance relative to a standard hydrogen electrode (2H+ + 2e- -> H2 = -0.42 V).
How does affinity for electrons relate to reduction potential?
The greater the affinity for e- , the larger the reduction potential; if electrons flow from Cu+ to Fe+3, then Fe+3 has a larger reduction potential (greater e- affinity)
than Cu+2
What is the relationship between standard reduction potential and standard free energy?
standard free energy = -nF(deltaEstandard)
n = number of electrons
F = faraday constant
deltaEstandard = Standard reduction potential of electron acceptor - Standard reduction potential of electron donor
What are the reduced and oxidized forms of redox coenzymes?
Reduced: NADH, FADH2, NADPH, FMNH2
Oxidized: NAD+, FAD, NADP+, FMN
What redox reactions occur in the citric acid cycle? In the ETC?
3 NAD+ are reduced to NADH
FAD reduced to FADH
In the ETC, electrons transferred from NADH to O2 to produce H20
