Q. 17.53 - An Introduction to General, Organic, and Biological Chemistry

Question

How is a peptide chain extended?

Step-by-Step Solution

Answer

 A peptide bond forms between the amino acids and first t RNA dissociate from the ribosome and returns cytoplasm. After the first $t$ RNA detaches from the ribosome, the ribosome shifts to the next codon on mRNA.

Step 1: Introduction

MRNA binds to ribosome after exiting the nucleus. At the location of protein production, t RNA bearing the proper amino acid interacts to mRNA on the ribosome. Protein synthesis occurs on two neighbouring locations on the ribosome's bigger subunit. A tRNA containing the anticodon for the second codon with the second amino acid binds to mRNA. The amino acids create a peptide bond, and the first t RNA dissociates from the ribosome and returns to the cytoplasm. The ribosome switches to the next codon on mRNA after the initial $t$ RNA detaches from the ribosome.

Step 2: Explanation

A fresh t RNA connects to the open binding site, and its amino acid forms a peptide bond with the preceding amino acid. The ribosome shifts down the mRNA to read the next codon after the previous t RNA detaches. The peptide chain is stretched in this way every time a peptide bond binds a new amino acid.