Bacterial Elongation Factor G

Bacterial elongation factor G (EF-G) is a highly conserved, essential protein that plays a central role in the process of protein synthesis (translation) in bacteria. It is a member of the GTPase superfamily and catalyzes the translocation step during translation, moving transfer RNA (tRNA) and messenger RNA (mRNA) through the ribosome. EF-G binds to the ribosome in its GTP-bound state after peptide bond formation and hydrolyzes GTP to GDP, inducing conformational changes necessary for translocation.

Fusidic acid traps EF-G on the ribosome post-translocation, inhibiting further rounds of elongation or recycling. Argyrin B binds an allosteric pocket on bacterial EF-G distinct from fusidic acid’s site, inhibiting protein synthesis by blocking translocation.