Fig. 2

Mutations and recombination in the ompC gene. a Alignment of OmpC L3L4 region from ST in which mutations or recombination events were detected. Loops L3 and L4 are indicated by lines above the sequences, and those positions predicted to be exposed to the pore lumen in E. coli MG1655 (ST10) by asterisks [50]. Mutation R195L and G137D associated with the gain of carbapenemase genes are highlighted by red rectangles. Numbering is according to MG1655 OmpC protein. b Maximum likelihood phylogenetic reconstruction of representative OmpC sequences. OmpC sequences are labeled according to the ST of origin. OmpC sequences tagged with “-Rec” in blue were acquired by recombination in their respective STs; independent recombination events with different ompC alleles within a single ST are numbered. Bootstrap values > 60 are indicated. c Antibiotic susceptibility testing (diameters of inhibition) of W3110 ΔompC ΔompF pOXA-232 strain complemented by different alleles of the ompC gene cloned in the medium copy number pACYC184 [43] according to the figure key. The empty vector was used as control. Bars represent standard deviations; *P < 0.05; **P < 0.01; ***P < 0.001