The amplified portion of CMY-genes detected in this study includes homologues of CMY-2, CMY-4, and two CMY -2 variants (CMY-42 and CMY-102) with percentage of similarity 99%.
Genes related to blaTEM, blaSHV, blaCMY-1, bla cmy -2, and blaCTX-M-3 were amplified with the oligonucleotide primers as described (23 ).
CMY-2 from Citrobacter freundii is the most frequently encountered type [65].
6-Aryloxy benzoxaborole 22 inhibited AmpC P99 and CMY-2 with Ki values in the low nanomolar range.
Seven primer pairs, newly designed from 44 β-lactamase genes encoding extended-spectrum β-lactamases not related to TEM- and SHV-types, were used to differentiate OXA-2, FOX-3, CMY-3, IMP-1, and IMI-1 β-lactamases.
Confirmed extended-spectrum β-lactamase rates for E. coli and Klebsiella spp. were only 4.8%and5.0%0%, respectively, with mobile AmpC (CMY-2 and FOX-5) enzymes shown in 13 additional Enterobacteriaceae isolates.
Plasmid-mediated AmpC (CMY-2) beta-lactamase resistance was associated with a clonal group of IncI1 plasmids that has remained stable in isolates collected up to a decade apart.
Such CMY-2 IncA/C plasmids have been also identified in E. coli isolates [8], [9].
Conjugation experiments from the original S. enterica host strains to E. coli recipient strain failed for the CMY-2 IncA/C plasmid pAM04528 and yielded many E. coli transconjugants for the CMY-2 IncA/C plasmid pN418.
We have tested epidemic successful plasmids carrying Extended Spectrum Cephalosporins (ESC) resistance genes encoding CTX-Ms, TEM-52 ESBLs, and CMY-2 AmpC β-lactamase [16].
The same result was also observed for the 4 current epidemic CMY-2 IncA/C MDR plasmids, i.e. p13956, p13688, pN418, and pAM04528 (Figure 1).
