The first report of the coproduction of CMY-16 and ArmA 16S rRNA methylases in carbapenemase-ESBL producing Escherichia coli isolates

Abstract

The main aim of this work was to assess the occurrence and to characterize AmpC genes and to investigate the co-existence of 16S rRNA methylases and carbapenemases genes among the ESBL producing Escherichia coli strains. 180 Escherichia coli clinical strains were collected from the university hospital of Constantine located in the eastern part of Algeria. 42 ESBL-producers were phenotypically identified and also confirmed genotypically able to produce CTX-M-15 [n=33], CTX-M-1 [n=5], CTX-M-14 [n=1], SHV-2 [n=1], and two strains have been revealed producing the blaOXA-48 genes associated with blaTEM-1. Among the ESBL-producing strains three expressed additionally an AmpC phenotype which corresponded to the carriage of a blaCMY gene shown by sequencing to correspond to CMY-2 (1 isolate) CMY-16 (2 isolates). The two E. coli isolates produce CMY-16 that belonged to phylogroup D while the single CMY-2 producing isolate belonged to phylogroup C. Antibiotic resistance of the aminoglycoside family by production of 16S rRNA methylases was detected by an end-point multiplex PCR assay which concerns genes coding for different 16S rRNA methylases (rmtD, rmtA, rmtB, armA, npmA, and rmtC). An armA gene was identified in 2 strains. This study shows for the first time the co-existance of CMY-16 and armA genes with blaTEM-1 and blaOXA-48 producing E. coli strains. DOI: http://dx.doi.org/10.5281/zenodo.3776651

Keywords

• AmpC β-lactamase CMY-16
• Escherichia coli
• ArmA 16S rRNA methylases
• ESBL coproduction