Figure 10.

The kinetic mechanism of translocation. The ribosome, mRNA, and EF-G are depicted as in Figure 7. In this figure, the newly deacylated P site tRNA that will be translocated into the E site and the newly formed A site peptidyl-tRNA at the A site that will be translocated into the P site are shown in red and orange, respectively. The L1 stalk of the 50S subunit and the head domain of the 30S subunit are shown in dark outlines on their respective subunits. The role that swiveling of the 30S subunit's head domain (denoted by the curved arrow superimposed onto the head domain) plays in translocation has been elucidated recently by cryo-EM (Ratje et al. 2010).