Methicillin resistance determinant protein FmtA (FmtA) (FmtA)

Methicillin resistance determinant protein FmtA (FmtA) is a cell wall-associated enzyme in Staphylococcus aureus that plays a critical role in the manifestation of methicillin resistance (UniProt Q2FW05). Although it shares structural homology with penicillin-binding proteins (PBPs), FmtA functions primarily as an esterase that removes D-alanine from lipoteichoic acids, which modifies the bacterial surface charge and peptidoglycan cross-linking (Rahman et al., 2016, PMID: 27166341). This modification is essential for the bacteria to maintain cell wall integrity in the presence of beta-lactam antibiotics. FmtA is considered a promising therapeutic target because its inhibition can sensitize MRSA strains to existing beta-lactams, potentially restoring the efficacy of drugs like oxacillin (Bissonnette et al., 2016, PMID: 27550356). Research indicates that FmtA interacts with various beta-lactams, albeit with lower affinity than traditional PBPs, and its absence leads to a significant reduction in oxacillin resistance levels (Fan et al., 2007, PMID: 17932022).

Other names

Factor affecting methicillin resistance AFmtAPBP-like protein FmtA

Inhibitors of FmtA act as resistance-breakers by preventing the deacylation of lipoteichoic acids, thereby sensitizing the bacteria to beta-lactam antibiotics.