Acta Pharm. 48 (1998) 1-7
Recent information on bacterial resistance to macrolide-lincosamid-streptogramin type B (MLS) antibiotics has been reviewed and discussed. The MLS antibiotics block protein synthesis by inhibiting the ribosome 50S subunit function. The Erm family of methyltransferases is responsible for the development of resistance to the MLS antibiotics. These enzymes methylate specific adenine of 23S ribosomal RNA that prevents the MLS antibiotics from binding to the ribosome and from exhibiting their antibacterial activity. The Erm methyltransferases show either constitutive or inducibile mode of synthesis and their expression is regulated entirely at the translational level. Structural features of ErmAM methyltransferase show the catalytic domain similarity and a novel fold of substrate binding domain in comparison to other methyltransferases. This opens up the possibility of designing a potent inhibitor that might block the resistance conferring methylation activity of the protein.
Keywords: MLS antibiotics, 23S rRNA, Erm methyltransferases, ErmC, ErmC', ErmAM, MLS resistance, inhibitors of Erm methyltransferases