The mRNA codon AUG is used as the start codon by organisms of all three domains of life. a. The organisms of all three domains use the same amino acid as the initial amino acid in translation is to be checked and explained. Similarities and differences are to be identified. b. Even though AUG being the most common start codon sequence, very less proteins have methionine as the first amino acid. Explain with reason. Introduction: Start codon of mRNA refers to the first codon of mRNA transcript that initiates the translation process. The start codon is AUG. It codes for methionine. Methionine is one of the amino acid that is encoded by a single codon in the genetic code. Not all proteins start with methionine, the second start codon is the modified form of methionine known as fMet. In prokaryotes, the initiation codon is fMet- formyl methionine. During the process of translation, tRNA molecule specifically recognizes the start codon with the help of initiation factors.

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Chapter 9, Problem 38P

Summary Introduction

To review:

The mRNA codon AUG is used as the start codon by organisms of all three domains of life.

a. The organisms of all three domains use the same amino acid as the initial amino acid in translation is to be checked and explained. Similarities and differences are to be identified.

b. Even though AUG being the most common start codon sequence, very less proteins have methionine as the first amino acid. Explain with reason.

Introduction:

Start codon of mRNA refers to the first codon of mRNA transcript that initiates the translation process. The start codon is AUG. It codes for methionine. Methionine is one of the amino acid that is encoded by a single codon in the genetic code. Not all proteins start with methionine, the second start codon is the modified form of methionine known as fMet. In prokaryotes, the initiation codon is fMet- formyl methionine. During the process of translation, tRNA molecule specifically recognizes the start codon with the help of initiation factors.

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