Chapter 9, Problem 23P

Summary Introduction

To analyze:

The amino acid sequence of a segment of a polypeptide is

$\text{N-Cys-Pro-Ala-Met-Gly-His-Lys-C}$

a. Describe the mRNA order encoding this polypeptide fragment? Use N to denote any nucleotide, Pu to represent purine, and Py to denote a pyrimidine. Also tag $\text{5'}$ and $\text{3'}$ ends of mRNA.

b. Determine the DNA template and coding strand orders corresponding to mRNA. Use the N, Pu, and Py signs as placeholders.

Introduction:

Genetic information of DNA is encoded in a tri-nucleotide code known as codons. Codons have specific characteristics- all the codons specify amino acids; there is one start codon and three stop codons also known as nonsense codons. The beginning and ending of the translation process requires specific codons. The Codons are present on mRNA and are read during translation from $\text{5'-3'}$. These genetic codes are universal.