Elongation factor G (Staphylococcus aureus) (EF-G)

Elongation factor G (EF-G), encoded by the fusA gene in Staphylococcus aureus, is an essential GTPase that facilitates the translocation step of protein translation (UniProt: P0A0H4). During this process, EF-G promotes the movement of the mRNA-tRNA complex within the ribosome following peptide bond formation, a step powered by GTP hydrolysis (PubMed: 24123365). In the context of Methicillin-resistant Staphylococcus aureus (MRSA), EF-G is the primary molecular target of the antibiotic fusidic acid. Fusidic acid works by binding to EF-G when it is in a complex with GDP and the ribosome, effectively preventing the conformational changes necessary for the factor's release and thereby stalling protein synthesis (PubMed: 10692341). Resistance to drugs targeting EF-G typically arises through chromosomal point mutations in the fusA gene or via the acquisition of plasmid-borne protection proteins like FusB or FusC, which physically displace the drug from the target (PubMed: 17601116). Because EF-G is vital for bacterial viability and possesses significant structural differences from eukaryotic elongation factors, it remains a high-value target for narrow-spectrum antimicrobial development against multi-drug resistant staphylococci.

Other names

FusATranslocaseGTP-binding protein EF-GEF-G1

Inhibition of bacterial protein synthesis by binding to the EF-G-GDP-ribosome complex, preventing the release of EF-G and stalling the translocation step of translation (PubMed: 24123365).