Question

Which of the following mutations are more likely to occur based on their codons, group classifications, and structures?

4) (20 points) Which of the following mutations are more likely to occur (aka more conservative) based on their codons (show the codons and underline anysingle nucleotide changes), group classifications, and structures (draw or describe the structures)? Circle or underline the mutation you believe is more conservative and explain your choices. BE SURE TO EXPLAIN WHY THE LESS CONSERVATIVE MUTATION IS LESS CONSERVATIVE! If you only mention in detail the substitution that you think is more conservative, you will lose half the available points. Afterwards, check the Blosum-62 matrix to determine if your guess was correct. Do not be lazy with your answer; thoroughly explain your choice like I did in the example. OR Glu→ Arginine OR

Answer 1

a. In this case

Phe->Trp is more conservative because both the amino acid have same biochemical property. For example, both are aromatic in structure, both are non-polar, both are hydrophobic (water repellent). Also, the Codon of Phe is similar to tryptophan.  

The Gln->Asn is less conservative because asparagine and glutamine structures are very different and their Codon structures are different.

b. In this case, Tyr->Cys is more conservative because both amino acid are polar amino acid, having same physiochemical property. Hence, this mutation is more conserved .

Glu->Arginine is less conserve because both have opposite nature. Glutamic acid is an acidic amino acid whereas arginine is a basic amino acid. Hence, both are different in their physicochemical characteristics.