{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T10:14:59Z","timestamp":1780913699251,"version":"3.54.1"},"reference-count":37,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,13]],"date-time":"2025-05-13T00:00:00Z","timestamp":1747094400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100018914","name":"Fujian Academy of Agriculture Science Research Project","doi-asserted-by":"publisher","award":["XTCXGC2021008"],"award-info":[{"award-number":["XTCXGC2021008"]}],"id":[{"id":"10.13039\/501100018914","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018914","name":"Fujian Academy of Agriculture Science Research Project","doi-asserted-by":"publisher","award":["CXTD2021007-2"],"award-info":[{"award-number":["CXTD2021007-2"]}],"id":[{"id":"10.13039\/501100018914","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018914","name":"Fujian Academy of Agriculture Science Research Project","doi-asserted-by":"publisher","award":["YDXM2023007"],"award-info":[{"award-number":["YDXM2023007"]}],"id":[{"id":"10.13039\/501100018914","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018914","name":"Fujian Academy of Agriculture Science Research Project","doi-asserted-by":"publisher","award":["ZYTS202422"],"award-info":[{"award-number":["ZYTS202422"]}],"id":[{"id":"10.13039\/501100018914","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: The emergence and transmission of the tigecycline resistance efflux pump gene cluster tmexCD-toprJ among humans, animals and the environment have posed a serious threat to public health. The objective of this study was to characterize Pseudomonas strains carrying multiple copies of tmexC6D6-toprJ1b from a pig farm and illustrate the genetic context of tmexC6D6-toprJ1b in the NCBI database. Methods: The characterization of Pseudomonas strains FJFQ21PNM23 and FJFQ21PNM24 was determined by antimicrobial susceptibility testing, whole-genome sequencing, and RT-qPCR. Results: The tmexCD-toprJ-positive P. mendocina strains FJFQ21PNM23 and FJFQ21PNM24 were isolated from nasal swabs in a pig farm. Sequence analysis showed that the two P. mendocina strains harbored multiple antimicrobial resistance genes, including tigecycline resistance gene tmexC6D6-toprJ1b. WGS analysis indicated that tmexC6D6-toprJ1b gene was located on a classical transferable module (int1-int2-hp1-hp2-tnfxB-tmexCD-toprJ) and a multiresistance region in FJFQ21PNM24 and FJFQ21PNM23, respectively. Further analysis revealed that 39 additional tmexC6D6-toprJ1b genes in the NCBI database were all identified in Pseudomonas spp., and the genetic features of tmexC6D6-toprJ1b were summarized into three distinct structures. Conclusions: This study is the first to identify and report the tigecycline resistance gene tmexCD-toprJ in a swine farm. Our findings summarize the three structures in the genetic context of tmexC6D6-toprJ1b and reveal that Pseudomonas serves as the only known reservoir of tmexC6D6-toprJ1b.<\/jats:p>","DOI":"10.3390\/antibiotics14050500","type":"journal-article","created":{"date-parts":[[2025,5,13]],"date-time":"2025-05-13T06:40:23Z","timestamp":1747118423000},"page":"500","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Multiple Copies of Tigecycline Gene Cluster tmexC6D6-toprJ1b in Pseudomonas mendocina in a Swine Farm"],"prefix":"10.3390","volume":"14","author":[{"given":"Renjie","family":"Wu","sequence":"first","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongliang","family":"Che","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Longbai","family":"Wang","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8198-5133","authenticated-orcid":false,"given":"Qiuyong","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bing","family":"He","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingli","family":"Qiu","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuemin","family":"Wu","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rujing","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yutao","family":"Liu","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lunjiang","family":"Zhou","sequence":"additional","affiliation":[{"name":"Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China"},{"name":"Fujian Animal Diseases Control Technology Development Center, Fuzhou 350013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e02930-19","DOI":"10.1128\/mBio.02930-19","article-title":"Emergence of a Plasmid-Encoded Resistance-Nodulation-Division Efflux Pump Conferring Resistance to Multiple Drugs, Including Tigecycline, in Klebsiella pneumoniae","volume":"11","author":"Lv","year":"2020","journal-title":"mBio"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"834","DOI":"10.1016\/S1473-3099(11)70177-3","article-title":"Efficacy and safety of tigecycline for the treatment of infectious diseases: A meta-analysis","volume":"11","author":"Tasina","year":"2011","journal-title":"Lancet Infect. Dis."},{"key":"ref_3","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. Microbiol."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Wang, C., Yang, J., Xu, Z., Lv, L., Chen, S., Hong, M., and Liu, J.H. (2024). Promoter regulatory mode evolution enhances the high multidrug resistance of tmexCD1-toprJ1. mBio, 15.","DOI":"10.1128\/mbio.00218-24"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Wang, C.Z., Gao, X., Liang, X.H., Lv, L.C., Lu, L.T., Yue, C., Cui, X.X., Yang, K.E., Lu, D., and Liu, J.H. (2023). Pseudomonas Acts as a Reservoir of Novel Tigecycline Resistance Efflux Pump tmexC6D6-toprJ1b and tmexCD-toprJ Variants. Microbiol. Spectr., 11.","DOI":"10.1128\/spectrum.00767-23"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"100925","DOI":"10.1016\/j.drup.2023.100925","article-title":"Aeromonas spp. from hospital sewage act as a reservoir of genes resistant to last-line antibiotics","volume":"67","author":"Wu","year":"2023","journal-title":"Drug Resist. Updat."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Wang, C., Gao, X., Zhang, X., Yue, C., Lv, L., Lu, L., and Liu, J.H. (2025). Emergence of two novel tmexCD-toprJ subtypes mediating tigecycline resistance in the megaplasmids from Pseudomonas putida. Microbiol. Res., 292.","DOI":"10.1016\/j.micres.2025.128051"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e105","DOI":"10.1016\/S2666-5247(23)00338-5","article-title":"Global emergence of Gram-negative bacteria carrying the mobilised RND-type efflux pump gene cluster tmexCD-toprJ variants","volume":"5","author":"Wu","year":"2024","journal-title":"Lancet Microbe"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1102","DOI":"10.1080\/22221751.2020.1768805","article-title":"Co-existence of a novel plasmid-mediated efflux pump with colistin resistance gene mcr in one plasmid confers transferable multidrug resistance in Klebsiella pneumoniae","volume":"9","author":"Sun","year":"2020","journal-title":"Emerg. Microbes Infect."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"e134","DOI":"10.1016\/S2666-5247(22)00326-3","article-title":"Hospital wastewater as a reservoir for the tigecycline resistance gene cluster tmexCD-toprJ","volume":"4","author":"Wu","year":"2023","journal-title":"Lancet Microbe"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Wu, X., Chen, G., Wang, P., Yang, L., Wu, Y., Wu, G., Li, H., and Shao, B. (2025). Co-existence of a novel RND efflux pump tmexC6D6.2-toprJ1b and bla(OXA-4) in the extensively drug-resistant Pseudomonas aeruginosa ST233 clone. Int. J. Food Microbiol., 428.","DOI":"10.1016\/j.ijfoodmicro.2024.110984"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e0070221","DOI":"10.1128\/msystems.00702-21","article-title":"Plasmids Shape the Current Prevalence of tmexCD1-toprJ1 among Klebsiella pneumoniae in Food Production Chains","volume":"6","author":"Peng","year":"2021","journal-title":"mSystems"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3159","DOI":"10.1093\/jac\/dkab325","article-title":"Novel tigecycline resistance gene cluster tnfxB3-tmexCD3-toprJ1b in Proteus spp. and Pseudomonas aeruginosa, co-existing with tet(X6) on an SXT\/R391 integrative and conjugative element","volume":"76","author":"Wang","year":"2021","journal-title":"J. Antimicrob. Chemother."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"e02229-20","DOI":"10.1128\/AAC.02229-20","article-title":"A Novel Transferable Resistance-Nodulation-Division Pump Gene Cluster, tmexCD2-toprJ2, Confers Tigecycline Resistance in Raoultella ornithinolytica","volume":"65","author":"Wang","year":"2021","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1311","DOI":"10.1093\/jac\/dkad080","article-title":"Emergence of a novel tigecycline resistance gene cluster tmexC3-tmexD5-toprJ2b in Oceanimonas sp. from chicken, China","volume":"78","author":"Wang","year":"2023","journal-title":"J. Antimicrob. Chemother."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Gao, X., Wang, C., Lv, L., He, X., Cai, Z., He, W., Li, T., and Liu, J.H. (2022). Emergence of a Novel Plasmid-Mediated Tigecycline Resistance Gene Cluster, tmexCD4-toprJ4, in Klebsiella quasipneumoniae and Enterobacter roggenkampii. Microbiol. Spectr., 10.","DOI":"10.1128\/spectrum.01094-22"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1186\/s13756-015-0050-y","article-title":"Antimicrobial use in Chinese swine and broiler poultry production","volume":"4","author":"Krishnasamy","year":"2015","journal-title":"Antimicrob. Resist. Infect. Control"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Mulchandani, R., Wang, Y., Gilbert, M., and Van Boeckel, T.P. (2023). Global trends in antimicrobial use in food-producing animals: 2020 to 2030. PLoS Glob Public Health, 3.","DOI":"10.1371\/journal.pgph.0001305"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"e0042923","DOI":"10.1128\/msystems.00429-23","article-title":"Integrative conjugative elements mediate the high prevalence of tmexCD3-toprJ1b in Proteus spp. of animal source","volume":"8","author":"Peng","year":"2023","journal-title":"mSystems"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Sun, L., Wang, H., Meng, N., Wang, Z., Li, G., Jiao, X., and Wang, J. (2023). Distribution and Spread of the Mobilized RND Efflux Pump Gene Cluster tmexCD-toprJ in Klebsiella pneumoniae from Different Sources. Microbiol. Spectr., 11.","DOI":"10.1128\/spectrum.05364-22"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"e0271220","DOI":"10.1128\/AAC.02712-20","article-title":"Characterization of TMexCD3-TOprJ3, an RND-Type Efflux System Conferring Resistance to Tigecycline in Proteus mirabilis, and Its Associated Integrative Conjugative Element","volume":"65","author":"Wang","year":"2021","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"e846","DOI":"10.1016\/S2666-5247(22)00221-X","article-title":"Distribution and spread of the mobilised RND efflux pump gene cluster tmexCD-toprJ in clinical Gram-negative bacteria: A molecular epidemiological study","volume":"3","author":"Dong","year":"2022","journal-title":"Lancet Microbe"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"e0059221","DOI":"10.1128\/mSphere.00592-21","article-title":"A Transferable IncC-IncX3 Hybrid Plasmid Cocarrying bla(NDM-4), tet(X), and tmexCD3-toprJ3 Confers Resistance to Carbapenem and Tigecycline","volume":"6","author":"Hirabayashi","year":"2021","journal-title":"mSphere"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1455","DOI":"10.1093\/jac\/dkab044","article-title":"Emergence of a multidrug resistance efflux pump with carbapenem resistance gene blaVIM-2 in a Pseudomonas putida megaplasmid of migratory bird origin","volume":"76","author":"Li","year":"2021","journal-title":"J. Antimicrob. Chemother."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"e02178-20","DOI":"10.1128\/AAC.02178-20","article-title":"IS26 Mediates the Acquisition of Tigecycline Resistance Gene Cluster tmexCD1-toprJ1 by IncHI1B-FIB Plasmids in Klebsiella pneumoniae and Klebsiella quasipneumoniae from Food Market Sewage","volume":"65","author":"Wan","year":"2021","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Wang, C.Z., Gao, X., Tu, J.Y., Lv, L.C., Pu, W.X., He, X.T., Jiao, Y.X., Deng, Y.T., and Liu, J.H. (2022). Multiple Copies of Mobile Tigecycline Resistance Efflux Pump Gene Cluster tmexC2D2.2-toprJ2 Identified in Chromosome of Aeromonas spp.. Microbiol. Spectr., 10.","DOI":"10.1128\/spectrum.03468-22"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"109099","DOI":"10.1016\/j.envint.2024.109099","article-title":"Emergence and genomic epidemiology of tigecycline resistant bacteria of fly origin across urban and rural China","volume":"193","author":"Yan","year":"2024","journal-title":"Environ. Int."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"100989","DOI":"10.1016\/j.drup.2023.100989","article-title":"Identification of TMexCD-TOprJ-producing carbapenem-resistant Gram-negative bacteria from hospital sewage","volume":"70","author":"Zhu","year":"2023","journal-title":"Drug Resist. Updat."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Peng, K., Liu, Y.X., Sun, X., Wang, Q., Song, L., Wang, Z., and Li, R. (2024). Large-scale bacterial genomic and metagenomic analysis reveals Pseudomonas aeruginosa as potential ancestral source of tigecycline resistance gene cluster tmexCD-toprJ. Microbiol. Res., 285.","DOI":"10.1016\/j.micres.2024.127747"},{"key":"ref_30","unstructured":"Clinical and Laboratory Standards Institute (CLSI) (2021). Performance Standards for Antimicrobial Susceptibility Testing\u201431th Edition: M100, Clinical and Laboratory Standards Institute (CLSI)."},{"key":"ref_31","unstructured":"EUCAST (2019). Breakpoint Tables for Interpretation of MICs and Zone Diameters, Version 9.0, European Committee on Antimicrobial Susceptibility Testing."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1089\/cmb.2012.0021","article-title":"SPAdes: A new genome assembly algorithm and its applications to single-cell sequencing","volume":"19","author":"Bankevich","year":"2012","journal-title":"J. Comput. Biol."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Wick, R.R., Judd, L.M., Gorrie, C.L., and Holt, K.E. (2017). Unicycler: Resolving bacterial genome assemblies from short and long sequencing reads. PLoS Comput. Biol., 13.","DOI":"10.1371\/journal.pcbi.1005595"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"2640","DOI":"10.1093\/jac\/dks261","article-title":"Identification of acquired antimicrobial resistance genes","volume":"67","author":"Zankari","year":"2012","journal-title":"J. Antimicrob. Chemother."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1009","DOI":"10.1093\/bioinformatics\/btr039","article-title":"Easyfig: A genome comparison visualizer","volume":"27","author":"Sullivan","year":"2011","journal-title":"Bioinformatics"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Yang, J., Wu, R., Xia, Q., Yu, J., Yi, L.X., Huang, Y., Deng, M., He, W.Y., Bai, Y., and Lv, L. (2023). The evolution of infectious transmission promotes the persistence of mcr-1 plasmids. mBio, 14.","DOI":"10.1128\/mbio.00442-23"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1006\/meth.2001.1262","article-title":"Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method","volume":"25","author":"Livak","year":"2001","journal-title":"Methods"}],"container-title":["Antibiotics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-6382\/14\/5\/500\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:31:39Z","timestamp":1760031099000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-6382\/14\/5\/500"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,13]]},"references-count":37,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2025,5]]}},"alternative-id":["antibiotics14050500"],"URL":"https:\/\/doi.org\/10.3390\/antibiotics14050500","relation":{},"ISSN":["2079-6382"],"issn-type":[{"value":"2079-6382","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,5,13]]}}}