Exam (elaborations)
ACS BIOCHEMISTRY EXAM 2024 Questions and Verified Answers, 100% Guarantee Pass
- Course
- Institution
ACS BIOCHEMISTRY EXAM 2024 Questions and Verified Answers, 100% Guarantee Pass
[Show more]
Content preview
ACS BIOCHEMISTRY EXAM-.pdf file:///C:/Users/HP/Desktop/New%20folder/ACS%20BIOCHEMISACS BIOCHEMISTRY EXAM
1. Henderson-Hasselbach Equation
Answer pH = pKa + log ([A-] / [HA])
2. FMOC Chemical Synthesis
Answer Used in synthesis of a growing amino acid chain toa polystyrene bead. FMOC is used as
a protecting group on the N-terminus.
3. Salting Out (Purification)
Answer Changes soluble protein to solid precipitate. Proteinprecipitates when the charges on
the protein match the charges in the solution.
4. Size-Exclusion Chromatography
Answer Separates sample based on size with smallermolecules eluting later.
5. Ion-Exchange Chromatography
Answer Separates sample based on charge. CM at-tracts +, DEAE attracts -. May have
repulsion effect on like charges. Salt or acid used to remove stuck proteins.
6. Hydrophobic/Reverse Phase Chromatography
Answer Beads are coated with a car-bon chain. Hydrophobic proteins stick better. Elute with
1 of 44 9/5/2024, 3:18
,ACS BIOCHEMISTRY EXAM-.pdf file:///C:/Users/HP/Desktop/New%20folder/ACS%20BIOCHEMIS
non-H-bonding solvent (acetonitrile).
7. Affinity Chromatography
Answer Attach a ligand that binds a protein to a bead. Elutewith harsh chemicals or similar
ligand.
8. SDS-PAGE
Answer Uses SDS. Gel is made from cross-linked polyacrylamide. Separatesbased off of mass with
smaller molecules moving faster.Visualized with Coomassieblue.
9. SDS
Answer Sodium dodecyl sulfate. Unfolds proteins and gives them uniform negativecharge.
10. Isoelectric Focusing
Answer Variation of gel electrophoresis where protein charge matters. Involves electrodes and
pH gradient. Protein stops at their pI when neutral.
11. FDNB (1-fluoro-2,3-dinitrobenzene)
Answer FDNB reacts with the N-terminus of theprotein to produce a 2,4-dinitrophenol
derivative that labels the first residue. Can repeat hydrolysis to determine sequential amino
acids.
12. DTT (dithiothreitol)
Answer Reduces disulfide bonds.
2 of 44 9/5/2024, 3:18
,ACS BIOCHEMISTRY EXAM-.pdf file:///C:/Users/HP/Desktop/New%20folder/ACS%20BIOCHEMIS
13. Iodoacetate
Answer Adds carboxymethyl group on free -SH groups. Blocks disulfidebonding.
14. Homologs
Answer Shares 25% identity with another gene
15. Orthologs
Answer Similar genes in different organisms
16. Paralogs
Answer Similar "paired" genes in the same organism
17. Ramachandran Plot
Answer Shows favorable phi-psi angle combinations. 3 main"wells" for ±h-elices, ß-sheets,
and left-handed ±h-elices.
18. Glycine Ramachandran Plot
Answer Glycine can adopt more angles. (H's forR-group).
19. Proline Ramachandran Plot
Answer Proline adopts fewer angles. Amino group isincorporated into a ring.
3 of 44 9/5/2024, 3:18
,ACS BIOCHEMISTRY EXAM-.pdf file:///C:/Users/HP/Desktop/New%20folder/ACS%20BIOCHEMIS
20. ±h-elices
Answer Ala is common, Gly & Pro are not very common. Side-chain inter- actions every 3
or 4 residues. Turns once every 3.6 residues. Distance betweenbackbones is 5.4Å.
21. Helix Dipole
Answer Formed from added dipole moments of all hydrogen bonds in an
±h-elix. N-terminus is ´+and C-terminus is ´-.
22. ß-sheet
Answer Either parallel or anti-parallel. Often twisted to increase strength.
23. Anti-parallel ß-sheet
Answer Alternating sheet directions (C & N-termini don't line-up).Has straight H-bonds.
24. Parallel ß-sheet
Answer Same sheet directions (C & N-termini line up). Has angledH-bonds.
25. 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.
26. Loops
Answer Not highly structured. Not necessary highly flexible, but can occasionallymove. Very
4 of 44 9/5/2024, 3:18
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 TIPSCORE. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $12.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
72964 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now
