Review Material I
Free Energy: ÆG = ÆH - TÆS
Enthalpy: heat of reaction based on bound energy since pressure and volume are basically constant for biological systems.
Entropy: measure of randomness of system. Generally entropy increases
in spontaneous process but not always therefore not good predictor or spontaneity.
negative ÆG = spontaneous reaction positive
ÆG = non-spontaneous reaction
Standard Free Energy Go': free energy under standard conditions
(298oC, 1M concentration of reactants, 1 atm, pH 7)
G' = Go' + RTlnK K = the product of the concentrations of product divided by product of reactant concentrations.
At equilibrium, G = 0 and therefore K = Keq. Keq = -ÆGo/RT
Coupled Reactions: a spontaneous reaction can drive a non-spontaneous reaction. Some examples of high energy molecules include, phosphoenolpyruvate; 1,3 diphosphoglycerate; acetyl-S-CoA; ATP
Characteristics by which proteins can be separated:
combinations of these characteristics can be used in one separation medium
Secondary structure: spatial arrangement of peptides in backbone. To determine helix, sheet or secondary structure prediction use Ramachandran plot, CD, or NMR.
Super-secondary structure: typical types include, meander, beta-alpha-beta, Greek key, nucleotide fold, leucine zipper/zinc finger
Tertiary structure: 3-D structure of entire polypeptide. The stabilization forces for this structure include, hydrogen bonds, hydrophobic interactions, ionic interactions, and disulfide bonds
Quaternary structure: spatial arrangement of subunits
Back to Biochem I tentative schedule
URL- http://www.wmich.edu/pathname/filename.html (if known, otherwise omit) Revised Date: June 24, 1997