Sometimes, Substitutions of One Amino Acid for Another in a Protein

Multiple Choice

Sometimes, substitutions of one amino acid for another in a protein results in a large change in secondary and tertiary structure. Sometimes, the substitution leads to very little change. The structure of valine is shown below. Which of the choices of amino acids given would probably cause the least amount of perturbation to protein structure if it was substituted for a valine?

A) a
B) b
C) c
D) d
E) e