FMOC Chemical Synthesis -ANSWER-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) -ANSWER-Changes soluble protein to solid
precipitate. Protein precipitates when the charges on the protein
match the charges in the solution.
Size-Exclusion Chromatography -ANSWER-Separates sample based
on size with smaller molecules eluting later.
Ion-Exchange Chromatography -ANSWER-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 -ANSWER-Beads are
coated with a carbon chain. Hydrophobic proteins stick better. Elute
with non-H-bonding solvent (acetonitrile).
Affinity Chromatography -ANSWER-Attach a ligand that binds a
protein to a bead. Elute with harsh chemicals or similar ligand.
,SDS-PAGE -ANSWER-Uses SDS. Gel is made from cross-linked
polyacrylamide. Separates based off of mass with smaller molecules
moving faster. Visualized with Coomassie blue.
SDS -ANSWER-Sodium dodecyl sulfate. Unfolds proteins and gives
them uniform negative charge.
Isoelectric Focusing -ANSWER-Variation of gel electrophoresis where
protein charge matters. Involves electrodes and pH gradient. Protein
stops at their pI when neutral.
FDNB (1-fluoro-2,3-dinitrobenzene) -ANSWER-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.
Iodoacetate -ANSWER-Adds carboxymethyl group on free -SH
groups. Blocks disulfide bonding.
Homologs -ANSWER-Shares 25% identity with another gene
Orthologs -ANSWER-Similar genes in different organisms
Paralogs -ANSWER-Similar "paired" genes in the same organism
Ramachandran Plot -ANSWER-Shows favorable phi-psi angle
combinations. 3 main "wells" for α-helices, ß-sheets, and left-handed
α-helices.
, Glycine Ramachandran Plot -ANSWER-Glycine can adopt more
angles. (H's for R-group).
Proline Ramachandran Plot -ANSWER-Proline adopts fewer angles.
Amino group is incorporated into a ring.
α-helices -ANSWER-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 -ANSWER-Formed from added dipole moments of all
hydrogen bonds in an α-helix. N-terminus is δ+ and C-terminus is δ-.
ß-sheet -ANSWER-Either parallel or anti-parallel. Often twisted to
increase strength.
Anti-parallel ß-sheet -ANSWER-Alternating sheet directions (C & N-
termini don't line-up). Has straight H-bonds.
Parallel ß-sheet -ANSWER-Same sheet directions (C & N-termini line
up). Has angled H-bonds.
ß-turns -ANSWER-Tight u-turns with specific phi-psi angles. Must
have gly at position 3. Proline may also be at ß-turn because it can
have a cis-omega angle.
Loops -ANSWER-Not highly structured. Not necessary highly flexible,
but can occasionally move. Very variable in sequence.
Circular Dichroism -ANSWER-Uses UV light to measure 2° structure.
Can be used to measure destabilization.
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 Tutorhailey. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $18.99. You're not tied to anything after your purchase.
