| Summary: | Resistance of bacteria to 3<sup>rd</sup> generation cephalosporins mediated by beta-lactamases (ESBL, pAmpC) is a public health concern. In this study, 1517 phenotypically cephalosporin-resistant <i>E. coli</i> were screened for the presence of <i>bla</i><sub>SHV</sub> genes. Respective genes were detected in 161 isolates. Majority (91%) were obtained from poultry production and meat. The SHV-12 beta-lactamase was the predominant variant (<i>n</i> = 155), while the remaining isolates exhibited SHV-2 (<i>n</i> = 4) or SHV-2a (<i>n</i> = 2). A subset of the isolates (<i>n</i> = 51) was further characterized by PCR, PFGE, or whole-genome sequencing and bioinformatics analysis. The SHV-12-producing isolates showed low phylogenetic relationships, and dissemination of the <i>bla</i><sub>SHV-12</sub> genes seemed to be mainly driven by horizontal gene transfer. In most of the isolates, <i>bla</i><sub>SHV-12</sub> was located on transferable IncX3 (~43 kb) or IncI1 (~100 kb) plasmids. On IncX3, <i>bla</i><sub>SHV-12</sub> was part of a Tn6 composite transposon located next to a Tn3 transposon, which harbored the fluoroquinolone resistance gene <i>qnrS1</i>. On IncI1 plasmids, <i>bla</i><sub>SHV-12</sub> was located on an incomplete class 1 integron as part of a Tn21 transposon. In conclusion, SHV-12 is widely distributed in German poultry production and spreads via horizontal gene transfer. Consumers are at risk by handling raw poultry meat and should take care in appropriate kitchen hygiene.
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