ACS BIOCHEMISTRY EXAM STUDY QUESTIONS AND ANSWERS UPDATED 2024
6 views 0 purchase
Course
ACS BIOCHEMISTRY
Institution
ACS BIOCHEMISTRY
Henderson-Hasselbach Equation - pH = pKa + log ([A-] / [HA])
FMOC Chemical Synthesis - Used in synthesis of a growing amino acid chain to a polystyrene bead. FMOC is used as a protecting group on the N-terminus.
Salting Out (Purification) - Changes soluble protein to solid precipitate. Protei...
FMOC Chemical Synthesis - Used in synthesis of a growing amino acid chain to a
polystyrene bead. FMOC is used as a protecting group on the N-terminus.
Salting Out (Purification) - Changes soluble protein to solid precipitate. Protein
precipitates when the charges on the protein match the charges in the solution.
Size-Exclusion Chromatography - Separates sample based on size with smaller
molecules eluting later.
Ion-Exchange Chromatography - Separates sample based on charge. CM attracts +,
DEAE attracts -. May have repulsion effect on like charges. Salt or acid used to remove
stuck proteins.
Hydrophobic/Reverse Phase Chromatography - Beads are coated with a carbon chain.
Hydrophobic proteins stick better. Elute with non-H-bonding solvent (acetonitrile).
Affinity Chromatography - Attach a ligand that binds a protein to a bead. Elute with
harsh chemicals or similar ligand.
SDS-PAGE - Uses SDS. Gel is made from cross-linked polyacrylamide. Separates
based off of mass with smaller molecules moving faster. Visualized with Coomassie
blue.
SDS - Sodium dodecyl sulfate. Unfolds proteins and gives them uniform negative
charge.
Isoelectric Focusing - Variation of gel electrophoresis where protein charge matters.
Involves electrodes and pH gradient. Protein stops at their pI when neutral.
ACS BIOCHEMISTRY EXAM
, ACS BIOCHEMISTRY EXAM
FDNB (1-fluoro-2,3-dinitrobenzene) - FDNB reacts with the N-terminus of the protein to
produce a 2,4-dinitrophenol derivative that labels the first residue. Can repeat hydrolysis
to determine sequential amino acids.
DTT (dithiothreitol) - Reduces disulfide bonds.
Iodoacetate - Adds carboxymethyl group on free -SH groups. Blocks disulfide bonding.
Homologs - Shares 25% identity with another gene
Orthologs - Similar genes in different organisms
Paralogs - Similar "paired" genes in the same organism
Ramachandran Plot - Shows favorable phi-psi angle combinations. 3 main "wells" for α-
helices, ß-sheets, and left-handed α-helices.
Glycine Ramachandran Plot - Glycine can adopt more angles. (H's for R-group).
Proline Ramachandran Plot - Proline adopts fewer angles. Amino group is incorporated
into a ring.
α-helices - Ala is common, Gly & Pro are not very common. Side-chain interactions
every 3 or 4 residues. Turns once every 3.6 residues. Distance between backbones is
5.4Å.
Helix Dipole - Formed from added dipole moments of all hydrogen bonds in an α-helix.
N-terminus is δ+ and C-terminus is δ-.
ß-sheet - Either parallel or anti-parallel. Often twisted to increase strength.
ACS BIOCHEMISTRY EXAM
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Bestzone. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.49. You're not tied to anything after your purchase.
