Study of VanA, B, C, D, E Genes in Vancomycin Resistant Enterococci Isolated from Retailed Dried Vegetables in Tehran, Iran

Abstract

Background: Enterococcus spp. are resistant to many antimicrobials including vancomycin. They may be found in foods and water. Objective: In the current study, van genes were investigated in vancomycin resistant enterococci (VRE) isolated from dried vegetables in Tehran, Iran. Materials and Methods: In this study, 140 dried vegetable samples were collected from local retailers in Tehran, Iran, 2015. Bacteria were isolated using culture, biochemistry and molecular methods. Susceptibility of the enterococcal isolates was assessed to six antibiotics of ampicillin, chloramphenicol, erythromycin, gentamicin, tetracycline and vancomycin using Kirby-Bauer method. The prevalence of vanA, B, C, D, E genes was molecularly studied in VRE using polymerase chain reaction (PCR) and sequencing techniques. Results: Of 140 dried vegetable samples, Enterococcus spp. strains were isolated from 84 samples (60%). Totally, 48% of the isolates were resistant to vancomycin. Of 41 vancomycinresistant enterococcal isolates, vanA was found in 23 (56.1%), vanB in 8 (19.5%) and vanC in 2 (4.9%) isolates. No vanD or vanE was found in the isolates. Results have shown a high rate of contamination with Enterococcus spp., especially VRE, in dried vegetables in Tehran. Conclusion: Therefore, further hygienic regulations such as personal training and food processing, transportation, storage and marketing must be routine in food industries and local retailers.

Enterococci, from Harmless Bacteria to a Pathogen

“…In addition to food-producing animals, VRE and their resistance genes have been reported and detected in foods at retail (meat, vegetables, cheese, and milk) [ 74 , 75 , 76 , 77 ]. This is a cause for enormous concern since it favors the dissemination of antimicrobial resistance organisms, consequently reducing therapeutic options [ 78 ].…”

Enterococci, from Harmless Bacteria to a Pathogen

“…In addition to food producing animals, VRE and their resistance genes have been reported and detected in foods at retail (meat, vegetables, cheese and milk) [74][75][76][77]. This is a cause for enormous concern since it favours the dissemination of antimicrobial resistance organisms, consequently reducing therapeutic options [78].…”