Test 1 Flashcards
Equilibrium
No net change in concentration of reactants over products
Steady State Equilibrium
Rate synthesis=rate degraded
Open system
Exchanges both energy and matter with surroundings
Closed system
Exchanges energy but not matter with surroundings
Diastereomers
Pairs of stereoisomers that are not enantiomers
Enantiomer
Nonsuperimposable mirror images of chiral molecules
Configuration
Fixed arrangement of atoms (how they’re connected to one another)
Ex: cis vs trans
Conformation
Rotational placement of atoms (where they are in space related to one another)
Ex: boat vs chair
Catabolism
Breakdown of biomolecules (spontaneous)
Anabolism
Synthesis of biomolecules (uses energy)
Strong acid
High Ka, low pKa
Weak acid
Low Ka, high pKa
Hydrolysis
Breaking a biomolecule by adding the elements of water
Condensation
Synthesizing a molecule by removing the elements of water
Hydrophobic Effect
Amphipathic molecules clump together in water to maximize hydrophilic-hydrophilic inxns; namely the hydrophobic region gets clumped on the interior
Salting Out
Adding salt to a protein solution to cause the protein to precipitate
Cationic exchange resin
Negative resin, thus exchanges positive groups (aka cations)
Ex: carboxymethyl cellulose
Anionic exhange resin
Positively charged resin that exchanges negatively charged groups (anions)
Ex: diethylaminoethyl Amine (DEAE)
Ion-exchange column separates based on:
Net charge of the molecules. The stronger the charge, the longer it stays on the resin
Size exclusion chromatography separates based on:
Size. Small things get stuck in the pores and large things come out first
Affinity chromatography separates based on:
Affinity for a ligand that is bound to the resin. Stronger the affinity, the slower it elutes; eluted with a ligand gradient
CA or Amide? -mate
CA
CA or Amide? -ine
Amide
pI
No net electric charge
Phi
Dihedral angle between N and alpha C
Psi
Dihedral angle between alpha carbon and carboxyl carbon
Specific Acitivity
Activity of an enzyme per mg of total protein. So mol of reactant transformed/min / mg of enzyme
Edman Degradation
Process of removing one amino acid from a polypeptide chain at a time to determine its sequence
Ms/MS or tandem MS
One Mass spec breaks down the polypeptide, the other gets Mr recordings
Charac of parallel beta sheets
Adjacent sheets go from N to C in the same direction
H bonding is at an angle btwn adjacent sheets
Distance for each repeating unit is 6.5A
Charac antiparallel beta sheets
Adjacent sheets go from N to C in opposite directions
H Bonding is linear
Distance for each repeating unit is 7A
Beta turn
Common sequence of aa that connects segments of antiparallel beta sheets; usually see G (flexible) and P (stays in cis configuration)
Henderson-Hasselbach Equation
pH= pKa + log ([A-]/[HA])
Beers Law
A=e(path length)(concentration)
pKa of COOH group in an AA
1.8-2.4
pKa of NH3 in AA
8.8-11.0
Charac of alpha helix
Each repeating unit is 5.4 A apart
3.6 aa per turn
H bonds are parallel to the axis of the helix
