{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T05:19:43Z","timestamp":1787721583046,"version":"build-2784847793"},"reference-count":69,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004837","name":"Spanish Ministry of Science and Innovation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100014181","name":"Junta de Extremadura","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100014181","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/01df4mv68","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100014181","name":"FEDER","doi-asserted-by":"publisher","award":["PID2020-118405RB-I00"],"award-info":[{"award-number":["PID2020-118405RB-I00"]}],"id":[{"id":"10.13039\/501100014181","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100014181","name":"FEDER","doi-asserted-by":"publisher","award":["IB20181"],"award-info":[{"award-number":["IB20181"]}],"id":[{"id":"10.13039\/501100014181","id-type":"DOI","asserted-by":"publisher"}]},{"name":"SECTI-JUNTAEX research group","award":["CTS059"],"award-info":[{"award-number":["CTS059"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background: Plasmid-mediated colistin resistance threatens the effectiveness of one of the last-line antibiotics for treating multidrug-resistant Gram-negative infections. Although wildlife is increasingly recognized as a reservoir of mobile antimicrobial resistance genes, its role in the emergence and dissemination of novel plasmid-mediated colistin resistance (mcr) genes remains poorly understood. Objectives: This study aimed to characterize two distinct mcr-carrying E. coli isolates identified in Spanish wildlife. Methods: Among 807 faecal samples from healthy wild animals screened, two mcr-positive E. coli isolates were identified. Genomic characterization included whole-genome sequencing, plasmid analysis, and functional assays, followed by heterologous expression and lipid A characterization by Ultra-High-Performance Liquid Chromatography coupled with High-Resolution Mass Spectrometry (UHPLC-HRMS). Results: Analysis of the two mcr-positive E. coli isolates revealed the first mcr-1-positive isolate from a wild boar (Sus scrofa) in Extremadura, Spain, carrying mcr-1 on a 33.3-kb conjugative IncX4 plasmid, while the isolate recovered from an Iberian lynx harbored mcr-13, a novel plasmid-borne mcr-like gene encoding a putative phosphoethanolamine (pEtN) transferase on a 163-kb non-conjugative plasmid. MCR-13 showed 82% amino acid identity with MCR-10, increased colistin MIC two-fold in a susceptible E. coli host, and mediated phosphoethanolamine modification of lipid A, although to a lower extent than MCR-1. Conclusions: The co-occurrence of established (mcr-1) and a novel mcr-like gene mcr-13, further supports the role of wildlife as a potential reservoir of emerging resistance genes and highlights the value of including wildlife in One Health surveillance programs.<\/jats:p>","DOI":"10.3390\/antibiotics15090822","type":"journal-article","created":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T13:20:43Z","timestamp":1787577643000},"page":"822","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Identification of mcr-13 in the Endangered Lynx pardinus, and mcr-1 in Sus scrofa, Expands the Diversity of Plasmid-Mediated Colistin Resistance Determinants of Escherichia coli from Wildlife"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6735-6760","authenticated-orcid":false,"given":"Pablo","family":"Pacheco","sequence":"first","affiliation":[{"name":"Departamento de Bioqu\u00edmica y Biolog\u00eda Molecular y Gen\u00e9tica, Facultad de Veterinaria, Universidad de Extremadura, 10003 Caceres, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luc\u00eda","family":"S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Innovaci\u00f3n en Gesti\u00f3n y Conservaci\u00f3n de Ingulados S.L., 10004 Caceres, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-4577-2180","authenticated-orcid":false,"given":"Jos\u00e9","family":"Luis P\u00edriz","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica y Biolog\u00eda Molecular y Gen\u00e9tica, Facultad de Veterinaria, Universidad de Extremadura, 10003 Caceres, Spain"},{"name":"Universidad Internacional de Valencia (VIU), 46002 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0797-3377","authenticated-orcid":false,"given":"Mar\u00eda","family":"Gil-Molino","sequence":"additional","affiliation":[{"name":"Unidad de Patolog\u00eda Infecciosa, Departamento de Sanidad Animal, Hospital Cl\u00ednico Veterinario, Universidad de Extremadura, 10003 Caceres, Spain"},{"name":"Instituto de Biotecnolog\u00eda Ganadera y Cineg\u00e9tica (INBIO G+C), Universidad de Extremadura, 10003 Caceres, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6425-4673","authenticated-orcid":false,"given":"Joaqu\u00edn","family":"Rey","sequence":"additional","affiliation":[{"name":"Unidad de Patolog\u00eda Infecciosa, Departamento de Sanidad Animal, Hospital Cl\u00ednico Veterinario, Universidad de Extremadura, 10003 Caceres, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pedro","family":"Fern\u00e1ndez-Llario","sequence":"additional","affiliation":[{"name":"Innovaci\u00f3n en Gesti\u00f3n y Conservaci\u00f3n de Ingulados S.L., 10004 Caceres, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda Jes\u00fas","family":"Palacios","sequence":"additional","affiliation":[{"name":"Direcci\u00f3n General de Caza, Pesca, Acuicultura, Tauromaquia y Medio Natural Junta de Extremadura, 06800 M\u00e9rida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9470-1315","authenticated-orcid":false,"given":"Jorge","family":"Pe\u00f1a","sequence":"additional","affiliation":[{"name":"Direcci\u00f3n General de Caza, Pesca, Acuicultura, Tauromaquia y Medio Natural Junta de Extremadura, 06800 M\u00e9rida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4745-3827","authenticated-orcid":false,"given":"Mar\u00eda Isabel","family":"Ige\u00f1o","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica y Biolog\u00eda Molecular y Gen\u00e9tica, Facultad de Veterinaria, Universidad de Extremadura, 10003 Caceres, Spain"},{"name":"Instituto de Productos C\u00e1rnicos (IPROCAR), Universidad de Extremadura, 10003 Caceres, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9952-977X","authenticated-orcid":false,"given":"Alberto","family":"Quesada","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica y Biolog\u00eda Molecular y Gen\u00e9tica, Facultad de Veterinaria, Universidad de Extremadura, 10003 Caceres, Spain"},{"name":"Instituto de Biotecnolog\u00eda Ganadera y Cineg\u00e9tica (INBIO G+C), Universidad de Extremadura, 10003 Caceres, 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