Final answer:
Two molecules of GTP are required to make a peptide bond between two amino acids during protein synthesis, fueling the binding and translocation processes via GTP hydrolysis.
Step-by-step explanation:
Making a peptide bond between two amino acids requires the hydrolysis of two molecules of GTP (guanosine triphosphate). In the elongation phase of protein synthesis, energy is needed for two main steps: the binding of a charged aminoacyl-tRNA to the A site of the ribosome and its subsequent translocation to the P site after the formation of the peptide bond. This energy is derived from GTP hydrolysis, which is catalyzed by specific elongation factors. The process of peptide bond formation is amazingly efficient, with the E. coli translation apparatus capable of adding an amino acid to the polypeptide chain in just 0.05 seconds. Consequently, a protein consisting of 200 amino acids can be synthesized in approximately 10 seconds.