{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,28]],"date-time":"2026-10-28T21:25:37Z","timestamp":1793222737683,"version":"4.5.0"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,26]],"date-time":"2025-03-26T00:00:00Z","timestamp":1742947200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ASPIRE, the technology program management pillar of Abu Dhabi\u2019s Advanced Technology Research Council (ATRC), via the ASPIRE Research Institute for Food Security in the Drylands (ARIFSID) project"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>This study investigates the occurrence, antimicrobial resistance (AMR) profiles, virulence factors, and plasmid composition of Enterococcus species isolated from salad ingredients in the United Arab Emirates (UAE). Four hundred salad vegetable items collected from local markets, over ten months through 2023, were screened, yielding an Enterococcus detection rate of 85.5% (342\/400). E. casseliflavus was the most commonly identified species (50%), followed by E. faecium (20%) and E. faecalis (16%). Among 85 Enterococcus isolates tested for antimicrobial susceptibility, 55.3% displayed resistance to at least one agent, with 18.8% classified as multidrug-resistant (MDR). All isolates were not resistant to ampicillin, linezolid, teicoplanin, tigecycline, and high-level gentamicin. Intrinsic phenotypic resistance to vancomycin was found in E. gallinarum and E. casseliflavus, while low-level (&lt;5%) ciprofloxacin and erythromycin resistance was sporadically detected in E. faecium and E. faecalis. Whole-genome sequencing (WGS) of 14 isolates (nine E. faecium, four E. faecalis, and one E. casseliflavus) unveiled a complex resistome. We report the first detection in salad vegetables of vancomycin resistance genes (vanC, vanXY-C2) in a vancomycin-susceptible E. faecalis isolate. Identifying tetM, ermB, and optrA genes in the studied isolates further underscored emerging resistance to tetracyclines, macrolides, and oxazolidinones. Concurrently, virulence gene analysis revealed 74 putative virulence factors, with E. faecalis harboring a higher diversity of biofilm-related and exoenzyme-encoding genes. One E. faecalis strain carried the cytolysin cluster (cylI, cylS, cylM), highlighting its pathogenic potential. Plasmid profiling identified 19 distinct plasmids, ranging from 3845 bp to 133,159 bp. Among the genome-sequenced isolates, mobilizable plasmids (47.3%) commonly carried AMR genes, especially tet(L) and tet(M), whereas conjugative plasmids (10.5%) did not harbor resistance determinants. These findings highlight that salad vegetables can still harbor and potentially transmit Enterococcus strains with clinically relevant resistance determinants and virulence traits. Enhancing foodborne AMR surveillance with WGS and targeted interventions is key to controlling its spread in the food.<\/jats:p>","DOI":"10.3390\/foods14071150","type":"journal-article","created":{"date-parts":[[2025,3,26]],"date-time":"2025-03-26T13:39:53Z","timestamp":1742996393000},"page":"1150","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Salad Vegetables as a Reservoir of Antimicrobial-Resistant Enterococcus: Exploring Diversity, Resistome, Virulence, and Plasmid Dynamics"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0938-0607","authenticated-orcid":false,"given":"Ihab","family":"Habib","sequence":"first","affiliation":[{"name":"Veterinary Public Health Research Laboratory, Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"},{"name":"ASPIRE Research Institute for Food Security in the Drylands (ARIFSID), United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2434-1411","authenticated-orcid":false,"given":"Mushtaq","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology and Immunology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"},{"name":"Zayed Center for Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6758-6040","authenticated-orcid":false,"given":"Glindya Bhagya","family":"Lakshmi","sequence":"additional","affiliation":[{"name":"Veterinary Public Health Research Laboratory, Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"},{"name":"ASPIRE Research Institute for Food Security in the Drylands (ARIFSID), United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9563-4393","authenticated-orcid":false,"given":"Mohamed-Yousif Ibrahim","family":"Mohamed","sequence":"additional","affiliation":[{"name":"Veterinary Public Health Research Laboratory, Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"},{"name":"ASPIRE Research Institute for Food Security in the Drylands (ARIFSID), United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2552-4807","authenticated-orcid":false,"given":"Akela","family":"Ghazawi","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology and Immunology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"},{"name":"Zayed Center for Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6102-0353","authenticated-orcid":false,"given":"Rami H.","family":"Al-Rifai","sequence":"additional","affiliation":[{"name":"Zayed Center for Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"},{"name":"Infectious Diseases Epidemiology Research Advancement Unit (IDERA), Institute of Public Health, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Habib, I., Khan, M., Mohamed, M.I., Ghazawi, A., Abdalla, A., Lakshmi, G., Elbediwi, M., Al Marzooqi, H.M., Afifi, H.S., and Shehata, M.G. (2023). Assessing the Prevalence and Potential Risks of Salmonella Infection Associated with Fresh Salad Vegetable Consumption in the United Arab Emirates. Foods, 12.","DOI":"10.3390\/foods12163060"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"107381","DOI":"10.1016\/j.micpath.2025.107381","article-title":"Enterococci for Human Health: A Friend or Foe?","volume":"201","author":"Wang","year":"2025","journal-title":"Microb. 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