Detecting ESBL-Encoding Genes by PCR

Possible ESBL production was confirmed by PCR. Five specific primer sets were used to detect beta-lactamase-encoding genes belonging to the bla_TEM, bla_SHV, and bla_CTX-M families (35 (link)– (link)38 (link)). The PCR products were visualized by gel electrophoresis on a 1% agarose-Tris-borate-EDTA (TBE) gel and stained with Midori green (Biozym Scientific GmbH, Hessisch Oldendorf, Germany). The resulting amplicons were purified using an innuPREP DOUBLEpure kit (Analytik Jena AG, Jena, Germany), according to the manufacturer’s recommendations. Custom sequencing was performed by Microsynth (Göttingen, Germany). The nucleotide sequences were analyzed using Chromas 2.6.5.