title: Occurrence of Multidrug Resistant Extended Spectrum Beta-Lactamase-Producing Bacteria on Iceberg Lettuce Retailed for Human Consumption.
abstract: Antibiotic resistance in bacteria is a global problem exacerbated by the dissemination of resistant bacteria via uncooked food, such as green leafy vegetables. New strains of bacteria are emerging on a daily basis with novel expanded antibiotic resistance profiles. In this pilot study, we examined the occurrence of antibiotic resistant bacteria against five classes of antibiotics on iceberg lettuce retailed in local convenience stores in Rochester, Michigan. In this study, 138 morphologically distinct bacterial colonies from 9 iceberg lettuce samples were randomly picked and tested for antibiotic resistance. Among these isolates, the vast majority (86%) demonstrated resistance to cefotaxime, and among the resistant bacteria, the majority showed multiple drug resistance, particularly against cefotaxime, chloramphenicol, and tetracycline. Three bacterial isolates (2.17%) out of 138 were extended spectrum beta-lactamase (ESBL) producers. Two ESBL producers (T1 and T5) were identified as Klebsiella pneumoniae, an opportunistic pathogen with transferable sulfhydryl variable- (SHV-) and TEM-type ESBLs, respectively. The DNA sequence analysis of the bla SHV detected in K. pneumoniae isolate T1 revealed 99% relatedness to bla SHV genes found in clinical isolates. This implies that iceberg lettuce is a potential reservoir of newly emerging and evolving antibiotic resistant bacteria and its consumption poses serious threat to human health.
authors.affiliation: Department of Biological Sciences, Oakland University, 375 Dodge Hall of Engineering, Rochester, MI 48309, USA.
authors.forename: Natasha
authors.identifier: 0000-0002-8160-7693
authors.initials: N
authors.lastname: Bhutani
authors.affiliation: Department of Biological Sciences, Oakland University, 375 Dodge Hall of Engineering, Rochester, MI 48309, USA.
authors.forename: Chithra
authors.identifier: 0000-0002-6739-7503
authors.initials: C
authors.lastname: Muraleedharan
authors.affiliation: Department of Biological Sciences, Oakland University, 375 Dodge Hall of Engineering, Rochester, MI 48309, USA ; Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, 4717 Saint Antoine Street, Detroit, MI 48201, USA.
authors.forename: Deepa
authors.initials: D
authors.lastname: Talreja
authors.affiliation: Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, 4717 Saint Antoine Street, Detroit, MI 48201, USA.
authors.forename: Sonia Walia
authors.initials: SW
authors.lastname: Rana
authors.affiliation: Department of Gastroenterology, Henry Ford Health System, Detroit, MI 48208, USA.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Walia
authors.affiliation: Department of Biological Sciences, Oakland University, 375 Dodge Hall of Engineering, Rochester, MI 48309, USA ; Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, 4717 Saint Antoine Street, Detroit, MI 48201, USA.
authors.forename: Ashok
authors.identifier: 0000-0001-6332-6591
authors.initials: A
authors.lastname: Kumar
authors.affiliation: Department of Biological Sciences, Oakland University, 375 Dodge Hall of Engineering, Rochester, MI 48309, USA.
authors.forename: Satish K
authors.initials: SK
authors.lastname: Walia
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D005516:Food Microbiology; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology / Q000235:genetics / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D018545:Lactuca / Q000382:microbiology*; D017720:Molecular Epidemiology; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases