{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T05:58:21Z","timestamp":1772517501729,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T00:00:00Z","timestamp":1772064000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32273068"],"award-info":[{"award-number":["32273068"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100016324","name":"Gansu Academy of Sciences","doi-asserted-by":"publisher","award":["2025QNTD44"],"award-info":[{"award-number":["2025QNTD44"]}],"id":[{"id":"10.13039\/501100016324","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012453","name":"China Agriculture Research System","doi-asserted-by":"publisher","award":["CARS-37"],"award-info":[{"award-number":["CARS-37"]}],"id":[{"id":"10.13039\/501100012453","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2022YFD1602201"],"award-info":[{"award-number":["2022YFD1602201"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The coexistence of antibiotic resistance genes (ARGs), particularly those conferring resistance to last-resort antibiotics, is increasingly present in lesser-studied bacterial species. Tigecycline is currently one of the last important barriers in the treatment of carbapenem-resistant bacterial infections, whose resistance gene, tet(X), is prevalent across multiple bacterial genera, but the coexistence of tet(X3) and tet(X4) in Acinetobacter sp. is rarely observed. Here, we report a strain co-harboring the chromosomal tet(X3) and plasmid-borne tet(X4) isolated from a commercial beef cattle farm in Henan province, China. The strain exhibited resistance to ampicillin, gentamicin, chloramphenicol, sulfamethoxazole, tetracycline, doxycycline, tigecycline, and omadacycline. Based on whole-genome sequencing (WGS), the strain was identified as A. indicus using Average Nucleotide Identity (ANI) and digital DNA\u2013DNA hybridization (dDDH). Chromosomal tet(X3) was identified in the genetic context, ISVsa3-XerD-tet(X3)-res-ISVsa3. The plasmid-located tet(X4) with the genetic context, ISVsa3-abh-tet(X4)-ISVsa3, and 14 additional resistance genes were located in multiple pdif modules. Two different typing methods, the Rep-based strategy (designed for A. baumanii) and MOB-typer, identified the tet(X4)-positive plasmid as GR31 and rep_cluster_1656, respectively. Conjugation assay failed to observe the transfer of the tet(X4)-positive plasmid into recipients, E. coli J53 and Salmonella LGJ2. The co-occurrence of tet(X3) and tet(X4) in Acinetobacter may suggest a risk of rapid dissemination of tigecycline resistance and the hidden presence of numerous undetected bacteria co-carrying high-risk ARGs in the agroecological system, both of which should cause particular concern.<\/jats:p>","DOI":"10.3390\/microorganisms14030541","type":"journal-article","created":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T16:57:13Z","timestamp":1772125033000},"page":"541","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Bovine-Derived Acinetobacter indicus Co-Harboring Chromosomal tet(X3) and Plasmid-Located tet(X4) Isolated from Henan, China"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-7459-1228","authenticated-orcid":false,"given":"Qing","family":"Wang","sequence":"first","affiliation":[{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China"},{"name":"College of Veterinary Medicine, Gansu Agricultural University, Lanzhou 730070, China"},{"name":"Key Laboratory of New Animal Drug Project of Gansu Province, Lanzhou 730050, China"},{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guonian","family":"Dai","sequence":"additional","affiliation":[{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China"},{"name":"College of Veterinary Medicine, Gansu Agricultural University, Lanzhou 730070, China"},{"name":"Key Laboratory of New Animal Drug Project of Gansu Province, Lanzhou 730050, China"},{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-7403-3953","authenticated-orcid":false,"given":"Yanhua","family":"Qiu","sequence":"additional","affiliation":[{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug Project of Gansu Province, Lanzhou 730050, China"},{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yaxin","family":"Zhou","sequence":"additional","affiliation":[{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug Project of Gansu Province, Lanzhou 730050, China"},{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jing","family":"Xu","sequence":"additional","affiliation":[{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug Project of Gansu Province, Lanzhou 730050, China"},{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Weiwei","family":"Wang","sequence":"additional","affiliation":[{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug Project of Gansu Province, Lanzhou 730050, China"},{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiyu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China"},{"name":"College of Veterinary Medicine, Gansu Agricultural University, Lanzhou 730070, China"},{"name":"Key Laboratory of New Animal Drug Project of Gansu Province, Lanzhou 730050, China"},{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1450","DOI":"10.1038\/s41564-019-0445-2","article-title":"Emergence of Plasmid-Mediated High-Level Tigecycline Resistance Genes in Animals and Humans","volume":"4","author":"He","year":"2019","journal-title":"Nat. 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