Exam (elaborations)
Biochem ACS Review Questions and Answers
- Course
- Institution
Exam of 6 pages for the course Biochemistry ACS at Biochemistry ACS (Biochem ACS Review)
[Show more]
Content preview
Biochem ACS ReviewWhat amino acids have nonpolar, aliphatic R groups? - answerGlycine, Alanine, Proline,
Valine, Leucine, Isoleucine, Methionine
What amino acids have polar, uncharged R groups? - answerSerine, Threonine,
Cysteine, Asparagine, and Glutamine
What amino acids have aromatic R groups? - answerPhenylalanine, Tyrosine, and
Tryptophan
What amino acids have negatively charged R groups? - answerAspartate and
Glutamate
What amino acids have positively charged R groups? - answerLysine, Arginine, and
Histidine
What is isoelectric focusing? - answerProteins are electrophoresed in a pH gradient gel.
Each protein will move in the gel as long as the protein contains a charge
What does SDS do? - answerIt binds to proteins and denatures it. All proteins have
same mass/ charge ratio
How do you determine the Amino Terminus? - answer1. Make a derivative of the N-
terminus with a marker molecule
2. Hydrolyze the peptide
3. N-terminal AA is identified by chromatography- modified amino acid will elute
differently than unmodified AA
What molecule does Edman Degradation use? - answerPhenyl Isothiocyanate (PTH)
What does Edman Degradation do? - answerIt removes one amino acid at a time. The
limit is 50 amino acids. After 50 amino acids, the polypeptide must be hydrolyzed into
smaller fractions
Where does Cyanogen Bromide cleave? - answerCleaves only on the caryboxyl side of
Methionine residues
Where does Trypsin cleave? - answerTrypsin cleaves on the carboxyl side of positive
residues such as Arginine and Lysine
What happens in Disulfide Position? - answerIt is a diagonal electrophoresis.
, The peptides are cleaved without destroying the disulfide bonds and then exposed to
performic acid vapors.
The performic acid vapors convert any S-X bond to a SO3-.
These fragments will be off the diagonal
In Peptide Synthesis, what is the protecting group? - answerFmoc
What is the group that activates amino acid 2? - answerDCC- Dicyclohexylcarbodiimide
What acts as the nucleophile in Peptide Synthesis? - answerAmino acid 1 that is
connected to the polystyrene bead.
What causes the polystyrene bead to disconnect from amino acid 1? - answerHF
In what order does peptide synthesis, synthesize amino acids? - answerCarboxy end to
the amine end
In what order does the body synthesize amino acids? - answerAmino terminus to
carboxy terminus
What are the hydrogen bonds in Alpha Helix? - answerThe carboxyl group is hydrogen
bonded with the Hydrogen on the Nitrogen 4 residues away. Alpha helix is clockwise, or
right handed
Which Beta Pleated sheet is more stable, parallel or antiparallel? - answerAntiparallel,
because there is a direct overlap of electrons which creates more stability
What does B-mercaptoethanol do? - answerIt breaks disulfide bonds
What does Urea do? - answerIt interrupts hydrogen bonds
What is Levinthal's Paradox? - answerIt is the difference between the calculated time for
a protein to fold and the real time it take for a protein to fold.
The discrepancy in time is answered by what? - answerProgressive stabilization
What is Progressive stabilization? - answerIt is the stabilization of intermediates that
resemble parts of the final folded state
What is the molten globule state? - answerIt is the state between random coil and native
state. It contains much secondary structure.
How is the molten globule formed? - answerIt is formed by hydrophobic collapse.
Hydrophobic residues are sequestered toward the inside of a protein
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 julianah420. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
60281 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now