Please answer the following questions (there may be more than one right answer):
ID: 48576 • Letter: P
Question
Please answer the following questions (there may be more than one right answer):
What is the best reason why proteins cannot fold randomly?
[ ] Random folding would take too long to get the correct conformation.
[ ] Random folding would result in highly disordered structures.
[ ] Random folding would lead do different structures for every molecule of a given protein.
[ ] They fold with chaperones.
Select all that apply. When a protein folds, it is trying to minimize:
[ ] Hydrogen bonding
[ ] Free energy
[ ] Ionic interactions
[ ] Van der Waal's interactions
Mark all true statements:
[ ] -sheets can be anti-parallel, parallel, or mixed
[ ] -sheets are composed of two or more -strands
[ ] -strands are tightly coiled, similar to -helices
[ ] -sheets can consist of sections of a polypeptide that are not near one another
Which of the following will likely result in a misfolded protein? Mark all that apply.
[ ] Mutation in DNA sequence.
[ ] Mutation in splice site.
[ ] Mutation in promoter.
[ ] Mutation resulting in aberrant STOP codon.
Explanation / Answer
What is the best reason why proteins cannot fold randomly?
Correct answer is: Random folding would take too long to get the correct conformation.
As their exists several pathways for protein folding, random folding would take a long time for protein to fold and get the correct confirmation.
When a protein folds, it is trying to minimize:
Correct answwer is :Free energy
Reason: Minimization of free energy results in addition of hydrogen bonds, hydrophobic interactions, and Van der Waal's interactions so that protein can fold properly to gain correct configuration.
Mark all true statements:
Correct answers would be:
Reason: Above statements apply to beta sheets.Two beta strands may lie next to each other but aminoacids of the adjacent strands that participate in bond formation do not lie adjacent to each other or we can say are not neighbours.
Which of the following will likely result in a misfolded protein?
Correct answers would be:
Reason:All of the above will result in misfolded protein.Mutation in DNA sequence will change the aminoacid sequence that could lead to misfolding.Mutation in splice site could result in presence of introns in mature mRNA that when translated to proteins would lead to misfolding of protein.Lastly, mutation in STOP codon will lead to folrmation of too long or too short protein that might not be able to fold properly.