 To complete its function, EF-P enters paused ribosomes through the E-site and facilitates peptide bond formation through interactions with the P-site tRNA.EF-P and eIF-5A both are essential for the synthesis of a subset of proteins containing proline stretches in all cells.It has been suggested that after binding of the initiator tRNA to the P/I site, it is correctly positioned to the P site by binding of EF-P to the E site.