task One can derive the coding DNA sequence from a protein sequence by \"back-tr

Question

task

One can derive the coding DNA sequence from a protein sequence by "back-translating" with the genetic code as the dictionary. Due to the degenerate genetic code, there are several theoretically possible DNA sequences that can encode a particular protein sequence. A peptide has the sequence

Met-Val-Asp-Ser-Asn-Trp-Ala-Gln-Cys-Asn-Pro-Ala-Thr

Within the 39-base pair area encoding this peptide, select the 20-base pair region where the number of different possible DNA sequences becomes the least possible. Record the consensus sequence for the selected 20-base pair region.

Use that:

N = an arbitrary base

Y = a pyrimidine

R = a purine

Explanation / Answer

Though the codon is triplet for the 20 bp we take seven amino acids long peptide.

Now the peptide is met-val-asp-ser-asn-trp-ala.

Codon of Met means methionine-ATG

Codon of val (valine) - GTT/GTC/GTA/GTG

codon for asp (asparagine) - GAT/GAG

Codon for ser (serine) - AGT/AGC/TCA/TCG/TCT/TCA

codon for asn (asparatic acid) - AAT/AAC

codon for trp (tryptophan) - TGG

Codon for ala (alanine) - GCT/GCC/GCA/GCG

So the sequence of 20 bp is-

ATG-GTN-GAY-TCN, AGY-AAY-TGG-GCN

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.