Detection of beta-lactamase genes, ERIC-PCR typing and phylogenetic groups of ESBL producing quinolone resistant clinical Escherichia coli isolates.

Escherichia coli are one of the most important agents in clinical settings. Treatment of E. coli infections are being complicated due to emergence of resistant bacteria which limits the choices of treatment. The extended spectrum of beta-lactamase (ESBL) producing and quinolone resistant E. coli isolates (n= 109) have been isolated from various clinical specimens belonging to both out-coming and in-coming patients of the Erciyes University Medical School Hospital of Turkey. Occurrence of genes encoding major type of beta-lactamases (bla(CTX-M), bla(SHV) and bla(TEM)) was investigated by using PCR among the isolates. ERIC-PCR typing was performed on the isolates. Moreover, phylogenetic groups were determined. The bla(CTX-M) was detected at the highest frequency (93%; 101/109), while the bla(SHV) and bla(TEM) were present in 65% (71/109) and 49% (56/109), respectively. Sequencing of beta-lactamase genes from several randomly selected isolates revealed that CTX-M-15 is the only CTX-M type enzyme, while there is variation in possessing SHV and TEM types of enzymes. Isolates harboring three bla genes were 32%. ERIC-PCR analyses, based on two different primers, demonstrated 5 to 6 clonal groups for 42 isolates. Phylo-grouping of all isolates was shown that majority of isolates was belonging to B2 (46%) and D (31%) major groups. The detection of genes encoding major beta-lactamases (bla(CTX-M), bla(SHV) and bla(TEM)) was very high in ESBL-producing quinolone resistant E. coli phenotypic isolates. It indicates that the molecular data was congruent with the phenotypic selection results