Protein Folding 1

Question 1

How did Anfinsen prove that protein structure is encoded in its primary sequence

Answer 1

1. He took Ribonuclease A and he put it in presence of denaturant urea and a reducing agent to reduce disulphide bonds and become unfolded then removed and added oxygen and refolded
2. Prove protein unfolded
3. Added oxygen back first
4. Disulphide bonds formed in unfolded state- cysteines closest to each other formed bonds
5. Different bonds to when they form when folded

Question 2

What was the thermodynamic hypothesis for protein folding

Answer 2

1. Found sequence was sufficient to fold
2. Protein folds to a native structure- minimum in free energy of folding