Fig. 1. EF-P arginine rhamnosylation and mode of action. Certain bacteria including P. aeruginosa, S. oneidensis, and N. meningitidis encode an EF-P variant with an invariant arginine at position 32. The glycosyltransferase EarP activates EF-P by rhamnosylation of Arg32 using dTDP-β-l-rhamnose as substrate. EF-P and its rhamnose modification stimulate proline–proline peptide bond formation thereby alleviating ribosome stalling at polyproline stretches. EF-P = translation elongation factor P; EarP = EF-P specific arginine rhamnosyl transferase for posttranslational activation.
