MLSBresistenssin

MLSBresistenssin, often referred to as MLS resistance, is a phenomenon observed in certain bacteria where they exhibit reduced susceptibility to macrolide, lincosamide, and streptogramin B (MLS) antibiotics. This class of antibiotics targets the bacterial ribosome, inhibiting protein synthesis. MLS resistance is a significant concern in clinical settings as it can lead to treatment failures for infections caused by susceptible bacteria.

The most common mechanism of MLS resistance is the modification of the ribosomal binding site by ribosomal RNA (rRNA) methylases. These enzymes, encoded by genes such as erm (erythromycin ribosome methylation), add methyl groups to specific nucleotides in the 23S rRNA component of the ribosome. This modification prevents the MLS antibiotics from binding effectively, rendering them inactive. Another mechanism involves active efflux pumps, encoded by genes like msr (macrolide streptogramin resistance), which actively transport the antibiotics out of the bacterial cell before they can reach their target. Less common mechanisms include target modification by specific protein binding or enzymatic inactivation of the antibiotic.

MLS resistance can be intrinsic, meaning it is naturally present in some bacterial species, or acquired through the transfer of resistance genes. This transfer can occur via mobile genetic elements like plasmids or transposons, facilitating the spread of resistance within and between bacterial populations. The widespread use and misuse of MLS antibiotics have contributed to the increasing prevalence of MLS resistance globally. This necessitates careful monitoring of resistance patterns and the judicious use of these antibiotics in both human and veterinary medicine to preserve their effectiveness.