Following peptide bond formation, GTP-bound eEF2 catalyzes the translocation of the deacylated tRNA in the P-site and the peptidyl-tRNA in the A-site (the pre-translocation state) into the E- and P- sites (the post-translocation state), respectively. Thus, the mRNA advances by three bases to expose the next codon in the A-site. After translocation, GDP-bound eEF2 leaves the ribosome to allow another round of elongation. eEF2 is reactivated by the release of GDP and binds GTP for subsequent rounds.
This process is illustrated below with a peptidyl-tRNA with a growing peptide, a deacylated tRNA with an -OH and a ribosome with A,P and E sites to accommodate these three forms of tRNA is also shown.