Question

mutations in the nucleic acid sequence of a gene can sometimes direct the substitution of one amino acid for another in the encoded protein. which amino acid substitution would be most likely to severely disrupt the normal structure of a protein? choose one: a. alanine to glycine b. leucine to isoleucine c. methionine to arginine d. asparagine to threonine e. tryptophan to phenylalanine

Explanation:

Glycine is unique as it has a hydrogen atom as its side - chain, giving it high flexibility in protein structure. Substituting alanine (which has a methyl side - chain) for glycine can severely disrupt protein structure because the lack of flexibility from the added methyl group can alter the protein's folding and conformation. Other substitutions involve amino acids with more similar side - chain properties and are less likely to cause such severe disruption.

Answer:

A. alanine to glycine