Abstracto

Antibiotic Resistance, Molecular Diversity & Verotoxin Characterization of E. coli Isolated from Clinical Samples

Ayesha Sultana, Drona Bhattacharya, Sammya Kumar Sen, Sreyasi Bhattacharya, Lakshmi Kanth R.N.

The objective of the present study is to determine the antibiotic resistance and analyse the genetic variation of Escherichia coli isolated from clinical samples. The clinical samples were collected from M. S. Ramaiah Teaching Hospital in Bangalore, India. The samples were collected from different patient with urinary tract infection. The isolates were cultured on selective media such as EMB agar. Determination of the physiological properties of strains was performed according to the biochemical tests recommended. The antibiotic susceptibility of the 48 E. coli samples was determined by Kirby-Bauer disc diffusion method and inhibition zone was measured. The bacteria showing zone of inhibition 10mm or less are considered as resistant bacteria and denoted as (R). For all the antibiotics these sample showed mixed results for susceptibility and resistance. Among the 48 samples 20 samples showed multiple drug resistance (MDR). After the E. coli cultures were screened for drug resistivity, their DNA was isolated from these cultures wherein thin strands of DNA were observed in each of the samples. From the RAPD PCR results obtained in this investigation, it was found that different banding patterns of the amplified products generated by 4 primers, had allowed the amplification of the DNA fragments of the E. coli isolates. The fingerprints generated by Gene i4 and Gene i6 primers revealed unique profiles for each strain in terms of number and position of bands. Subsequently, Verotoxin gene was detected using PCR with specific primers. Such information will be useful in classification, epidemiological survey, ecology and diagnosis.