Lecture 26. Introduction to metabolism
Wednesday 9 November 2016
Metabolism and thermodynamics. Metabolic flux and its control. "High energy" compounds. Thioesters. Oxidation-reduction reactions.
Reading: VVP4e - Ch.14, pp.436-461.
Summary
Thermodynamics dictates the direction and regulaory capacity of metabolic pathways
Control of metabolic flux
"High-energy" compounds: ATP and other compounds with high phosphoryl transfer potential.
Coupled reactions: driving an endergonic process by coupling it to a highly exergonic process so that the net process is exergonic.
Thioesters: Coenzyme A (CoA) is a thioester that serves as an acyl group carrier. Acetyl CoA is a central metabolite. Other thioesters in metabolism and enzymology.
Oxidation-reduction reactions
Electron carriers: NAD+, FAD.
The Nernst equation and thermodynamic spontaneity of redox reactions
Biochemical standard reduction potentials