During Protein biosynthesis, high energy bonds are not utilized in which one of the following steps?
Peptide Bond Formationi. The alpha amino group at the incoming amino acid in the "A" site forms a peptide bond (CONH) with carboxyl group of the peptidyl tRNA occupying the "P" site. This reaction is catalyzed by the enzyme peptidyl transferase (28S rRNA, a component of 60S subunit). This is an example of ribozyme; RNA acts as the enzyme.ii. Since the amino acid brought in by the tRNA is already activated, there is no need for fuher energy supply for the purpose of peptide bond formation. Now the growing peptide chain is occupying the "A" siteRef: Textbook of biochemistry (DM Vasudevan), 6th edition, page no. 492
Formation of aminoacyl RNA
Binding of aminoacyl tRNA to A site of ribosome
Formation of peptide bone (peptidyl transferase step)
Translocation step
Metabolism of protein and amino acid