Bioenergetics

Front 1

What are the 3 molecules that have higher standard free energies than ATP?

Back 1

1.) Phophoenolpyruvate
2.) 1,3-bisphosphoglycerate
3.) Phosphocreatine

Front 2

Which one has a higher free energy when hydrolyzed, oxygen ester or thioester?

Back 2

- Thioester (sulfur atom replaces the usual oxygen in the ester bond)
- undergo less resonance stabilization than oxygen esters

Front 3

How do phosphoryl groups flow from high-energy phosphoryl donors to acceptor molecules (like glucose)?

Back 3

- the phosphoryl group flows from high-energy phosphoryl donors to ATP then to acceptor molecules (glucose)
- flow is catalyzed by kinases
- hydrolysis of low-energy cps releases Pi

Front 4

Standard Reduction Potential Experiment

Back 4

- when 2 electrochemical half-cells, each containing the components of a half-reaction are connected, e- tends to flow to the half-cell with higher reduction potential
- the direction depends on electron potential of the 2
- a salt bridge of KCl provides path for counter-ion movement b/w cells
- from observed emf (electromotive force) and the known emf of reference cell, can find emf of test cell containing the redox pair
- cell that gains e-, have positive reduction potential

Front 5

Standard reduction potential (E'o)

Back 5

- at 0.816 V, O2 has the strongest reducing potential
- at 0, there is no flow
- at -.432, ferredoxin is the poorest at holding electrons

Front 6

NAD and NADP

Back 6

- nicotinamide adenine dinucleotide and its phosphorylated analog
- coenzymes
- undergoes reduction to NADH and NADPH, accepting a hydride ion (2e- and 1 proton) from an oxidizable substrate
- the "+" means it's oxidized
- the "H" means it has hydride ion

Front 7

Flavin nucleotides

Back 7

- flavin mononucleotide (FMN)
- flavin adenine dinucleotide (FAD)
- accept either 1 or 2 e- in the form of either 1 or 2 hydrogen atoms (each have an e- and a proton) from a reduced substrate
- fully reduced: FADH2
- semiquinone: has one e-, FADH'