title: Molecular characterization of Salmonella enterica serotype Enteritidis isolates from food and human samples by serotyping, antimicrobial resistance, plasmid profiling, (GTG)5-PCR and ERIC-PCR.
abstract: In recent years, Salmonella enterica serovar Enteritidis has been a primary cause of human salmonellosis in many countries. The major objective of this study was to investigate genetic diversity among Salmonella Enteritidis strains from different origins (food and human) by Enterobacterial Repetitive Intergenic Consensus (ERIC) -PCR, as well as to assess their plasmid profiling and antimicrobial resistance. A total of 30 Salmonella Enteritidis isolates, 15 from food samples (chicken, lamb, beef and duck meats) and 15 from clinical samples were collected in Tehran. Identification of isolates as Salmonella was confirmed by using conventional standard biochemical and serological tests. Multiplex-PCR was used for serotyping of isolates to identify Salmonella Enteritidis. Antimicrobial susceptibility testing to 16 agents founds drug resistance patterns among Salmonella Enteritidis isolates. No resistance was observed to cephalexin, ceftriaxone, ceftazidime and cefotaxime, ciprofloxacin, imipenem or meropenem, chloramphenicol and gentamicin. The highest resistance (96.7%) was observed to nitrofurantoin. Seven plasmid profiles (P1-P7) were detected, and a 68-kb plasmid was found in all isolates. Two different primers; ERIC and (GTG)5 were used for genotyping, which each produced four profiles. The majority of clinical and food isolates fell into two separate common types (CTs) with a similar percentage of 95% by ERIC-PCR. Using primer (GTG)5, 29 isolates incorporated in three CTs with 70% of isolates showing a single banding pattern. Limited genetic diversity among human and food isolates of Salmonella Enteritidis may indicate that contaminated foods were possibly the source of human salmonellosis. These results confirmed that ERIC-PCR genotyping has limited discriminatory power for Salmonella Enteritidis of different origin.
authors.affiliation: Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Science, Tehran, Iran.
authors.forename: F
authors.initials: F
authors.lastname: Fardsanei
authors.affiliation: Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Science, Tehran, Iran.
authors.forename: F
authors.initials: F
authors.lastname: Nikkhahi
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Food Microbiology Research Centre, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: B
authors.initials: B
authors.lastname: Bakhshi
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, University of Tehran, Iran.
authors.forename: T Z
authors.initials: TZ
authors.lastname: Salehi
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, University of Tehran, Iran; Department of Microbiology, Buali Sina University, Hamedan, Iran.
authors.forename: I A
authors.initials: IA
authors.lastname: Tamai
authors.affiliation: Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Science, Tehran, Iran; Food Microbiology Research Centre, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: M M
authors.initials: MM
authors.lastname: Soltan Dallal
keywords: Molecular characterization; Salmonella Enteritidis; plasmid profiling; resistance; serotyping