Question

A normal polypeptide includes the following sequence of amino acids. (Note: Each amino acid is named by a three-letter abbreviation.)

val his leu thr pro glu glu).
After a mutation, the amino acid sequence becomes the following:
val his leu thr proval glu
O
Is the mutation that occurred more likely to have been a substitution or an insertion? Explain your answer.

Answer 1

Based on the information provided, the mutation that occurred is more likely to have been an insertion rather than a substitution.

The original polypeptide has a sequence of six amino acids at the end that reads "glu glu," while the mutated polypeptide has an additional amino acid, "val," inserted between "pro" and "glu." This suggests that an extra amino acid was added to the sequence rather than one being substituted for another.

Substitutions involve the replacement of one amino acid with another, whereas insertions involve the addition of one or more amino acids to the sequence. In this case, the presence of an extra amino acid in the mutated polypeptide sequence indicates that an insertion mutation occurred.

Step-by-step explanation: