Figure 2.
Characterization of ST410 E. coli with putative blaCMY-185 vector. (a) ST410 population structure with the blaCMY-185-harbouring strain. A total of 15 ST410 isolates from 10 patients were identified through WGS from 2013 to 2019 locally. Ec1, Ec2 and Ec3 are indicated on the tree having <10 pairwise SNPs within this group. Ec3 is highlighted in red font with the novel blaCMY-185 variant (purple) indicated in the column. All IncIγ-positive isolates had 100% breadth of coverage when aligned with pCMY42-035148 (RefSeq #: GCF_003268695.1). ftsI and ompC mutations, which are predicted to contribute to reduced susceptibility to β-lactams based on previous studies,26,28 are indicated in the legend. (b) IncI-γ/K1 description harbouring blaCMY-185 with Kirby–Bauer (KB) disc diffusion testing results from conjugation experiments. The 34 kbp plasmid has the ORF labelled based on function as highlighted in legend. The blaCMY-185-encoding gene is labelled in red. Zone diameters for the recipient (J53) and the transconjugant clone (J53 + pMB7671_5) are in the accompanying table with susceptibility (S) and resistance (R) labelled based on the CLSI guidelines.12 AMP, ampicillin; CAZ, ceftazidime; CAZ + APB, ceftazidime + 3-aminophenylboronic acid (300 mg); CZA, ceftazidime/avibactam; FOX, cefoxitin; MEM, meropenem.