If you are performing site-directed mutagenesis to test predictions about which residues are essential for a protein’s function. Which of each pair of amino acid substitutions listed below would you expect to disrupt protein structure the most? And why? how do you go abouts knowing this?

a) Val replaced by Phe.

b) Lys replaced by Asp.

c) Gln replaced by Glu.

d) Pro replaced by His.

Explanation:

a) Although both amino acids are hydrophobic, Phe is a larger amino acid.

b) Since the Lys residue is positively charged and for that reason it would be more damaging to the protein.

c) The amide of the amino acid Asn would be the best option as a substitute for Gln than the amino acid Glu.

d) Due to the restricted geometry of the amino acid Pro, since the amino acid Gly does not have a side chain.

just here for the other one bc they put up with u