An in ‐house 45‐plex array for the detection of antimicrobial resistance genes in Gram‐positive bacteria

We describe an in-house bead array targeting AMR genes of Gram-positive bacteria and allowing their rapid detection all at once at a reduced cost. A total of 41 AMR probes were designed to target genes frequently associated with resistance to tetracycline, macrolides, lincosamides, streptogramins, pleuromutilins, phenicols, glycopeptides, aminoglycosides, diaminopyrimidines, oxazolidinones and particularly shared amongEnterococcus andStaphylococcus spp. A collection of 124 enterococci and 62 staphylococci isolated from healthy livestock animals through the official Belgian AMR monitoring (2018 –2020) was studied with this array from which a subsample was further investigated by whole-genome sequencing. The array detected AMR genes associated with phenotypic resistance for 93.0% and 89.2% of the individual resistant phenotypes in enterococci and staphylococci, respectively. Although line zolid is not used in veterinary medicine, linezolid-resistant isolates were detected. These were characterized by the presence ofoptrA andpoxtA, providing cross-resistance to other antibiotics. Rarer, vancomycin resistance was conferred by thevanA or by thevanL cluster. Numerous resistance genes circulating amongEnterococcus andStaphylococcus spp. were detected by this array allowing rapid screening of a large strain collection at an affordable cost. Our data stress the importance of interpreting AMR with caution and the complementarity of both phenotyping and genotyping methods. This array ...
Source: MicrobiologyOpen - Category: Microbiology Authors: Tags: ORIGINAL ARTICLE Source Type: research