Question

Which step of translation does not consume a high energy phosphate bond?
(A) Translocation
(B) Amino acid activation
(C) Peptidyl-transferase reaction
(D) Aminoacyl tRNA binding to active ribosomal site

Answer 1

Hint: A cell produces proteins through the process of translation using the genetic material delivered by messenger RNA (mRNA). The information included in the mRNA, which is created by copying DNA, instructs the cell on how to assemble proteins from amino acids. The peptidyl-transferase process is the only one that is energy-free. Energy and initiation factors are involved in the binding of aminoacyl-tRNA to the ribosome.

Complete Step by Step Answer:
Translation processes in four steps that are activation, initiation, elongation, and termination. Amino acid activation means that the right amino acid will be recognized, and there will be enough energy for the creation of peptide bonds thanks to activation. Amino acids are covalently coupled to particular adapter molecules during activation. The transfer RNA molecules serve as the adapters (tRNA). Translocation is the process that moves the mRNA-tRNA moiety forward on the ribosome during the elongation cycle of translation, enabling the next codon to enter the decoding center. Aminoacyl site, also known as A-site, and peptide site, sometimes known as P-site, are the two binding sites on ribosomes. At the P-site of the ribosome is the first amino acid, methionine. Amino acyl tRNA, the following incoming tRNA, is attached to the A-site.
A block of genes from one chromosome gets moved to another non-homologous chromosome in a translocation, a type of rearrangement. Aminoacyl tRNA synthase and ATP are both required for amino acid activation, which is the addition of an amino acid to tRNA. The enzyme peptidyl transferase creates a peptide link between two nearby amino acids, catalyzing the peptidyl transferase reaction. A high energy phosphate bond, such as ATP or GTP, is not consumed in this reaction. After tRNA is activated, aminoacyl tRNA attaches to the A site of the bigger ribosomal unit, and elongation factor EF-G uses one GTP in this step. Therefore, "Peptidyl transferase reaction" is the right response.
So, option (C) is the correct answer.

Note: The start codon designates the beginning of translation into a protein sequence, and the stop codon designates the end of translation. As stop codons do not encode for any amino acid but rather mark the end of the process of protein synthesis that is translation, they are also known as nonsense codons.