Question

For every single amino acid incorporated in peptide chain ______ ATP and ______ GTP molecules are used.

• A. 1, 4
• B. 1, 6
• C. 1, 2
• D. 1, 3

Answer 1

The correct option is A 1, 4

In order to be incorporated in the peptide chain, an amino acid has to attached to the respective tRNA, so that it can brought to the translational machinery as and when required by the codon of mRNA. In this process of attachment to the tRNA, also called the charging of tRNA, 1 ATP is used.

In the initiation step of translation process, 1 GTP is used to make the 30S complex of the ribosome. In the elongation step of the translation 2 GTPs are used, 1 GTP for positioning the incoming tRNA and the other for the translocation of the ribosome to continue the elongation process. In the termination process of the translation, 1 GTP is used to release the newly formed polypeptide chain. So, for every single amino acid incorporated in peptide chain 1 ATP and 4 GTP molecules re used.

Hence, the correct answer is '1,4'