Lipid II:glycine glycyltransferase (FmhB)

FmhB, also known as FemX, is an essential glycyltransferase in Staphylococcus aureus that plays a pivotal role in the biosynthesis of the bacterial cell wall [1, 3]. It specifically catalyzes the attachment of the first glycine residue to the L-lysine of the peptidoglycan stem peptide (Lipid II), a step that is prerequisite for the subsequent addition of four more glycines by FemA and FemB [1, 2, 33]. This pentaglycine interpeptide bridge is crucial for the structural integrity of the peptidoglycan layer and is a key determinant of high-level methicillin resistance in MRSA strains [1, 37]. Because FmhB is essential for bacterial survival and lacks a human homolog, it is considered a high-value target for the development of novel antibiotics [1, 23, 33]. Recent research has explored drug repurposing (e.g., Lumacaftor) and the design of stable tRNA analogues as potential inhibitors to combat multidrug-resistant staphylococcal infections [23, 24, 32].

Other names

FemXFactor essential for expression of methicillin resistance XLipid II:glycine transferase

Catalyzes the transfer of the first glycine residue from glycyl-tRNA to the epsilon-amino group of the L-lysine residue in the stem peptide of Lipid II, initiating the synthesis of the pentaglycine interpeptide bridge in Staphylococcus aureus peptidoglycan.