Extended spectrum beta lactamases investigation in Escherichia coli strains isolated from clinical samples by molecular method

156 of Esherichia coli isolates which have been determined extended spectrum beta lactamase-(ESBL) production by double disk synergy test in Gazi University, Clinical Microbiology Laboratory were used in this study. From this isolates DNA was isolated by boiling technique. It is investigated the presence of TEM type beta lactamase by polymerase chain reaction (PCR) in 156 of E. coli strains. According to polymerase chain reaction results, it was determined 53.2% TEM type beta lactamase in 156 of E. coli strains. Confirmation of ESBLs production was carried out by the microdilution assay using amoxicillin and cefotaxime in the presence and absence of clavulanic acid. Our results indicate that the majority of ESBLs were expressed in E. coli.