{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T09:24:06Z","timestamp":1787563446293,"version":"build-2736575974"},"reference-count":43,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T00:00:00Z","timestamp":1636588800000},"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":["32072921 & 31502115"],"award-info":[{"award-number":["32072921 & 31502115"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The evolution of resistance in Salmonella to fluoroquinolones (FQs) under a broad range of sub-inhibitory concentrations (sub-MICs) has not been systematically studied. This study investigated the mechanism of resistance development in Salmonella enterica serovar Enteritidis (S. Enteritidis) under sub-MICs of 1\/128\u00d7MIC to 1\/2\u00d7MIC of enrofloxacin (ENR), a widely used veterinary FQ. It was shown that the resistance rate and resistance level of S. Enteritidis varied with the increase in ENR concentration and duration of selection. qRT-PCR results demonstrated that the expression of outer membrane porin (OMP) genes, ompC, ompD and ompF, were down-regulated first to rapidly adapt and develop the resistance of 4\u00d7MIC, and as the resistance level increased (\u22658\u00d7MIC), the up-regulated expression of efflux pump genes, acrB, emrB amd mdfA, along with mutations in quinolone resistance-determining region (QRDR) gradually played a decisive role. Cytohubba analysis based on transcriptomic profiles demonstrated that purB, purC, purD, purF, purH, purK, purL, purM, purN and purT were the hub genes for the FQs resistance. The \u2018de novo\u2019 IMP biosynthetic process, purine ribonucleoside monophosphate biosynthetic process and purine ribonucleotide biosynthetic process were the top three biological processes screened by MCODE. This study first described the dynamics of FQ resistance evolution in Salmonella under a long-term selection of sub-MICs of ENR in vitro. In addition, this work offers greater insight into the transcriptome changes of S. Enteritidis under the selection of ENR and provides a framework for FQs resistance of Salmonella for further studies.<\/jats:p>","DOI":"10.3390\/ijms222212218","type":"journal-article","created":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T23:02:41Z","timestamp":1636671761000},"page":"12218","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["The Evolution of Fluoroquinolone Resistance in Salmonella under Exposure to Sub-Inhibitory Concentration of Enrofloxacin"],"prefix":"10.3390","volume":"22","author":[{"given":"Yufeng","family":"Gu","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China"},{"name":"MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lulu","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China"},{"name":"MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cuirong","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China"},{"name":"MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junhong","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China"},{"name":"MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0199-5700","authenticated-orcid":false,"given":"Haihong","family":"Hao","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China"},{"name":"MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zonghui","family":"Yuan","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China"},{"name":"MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guyue","family":"Cheng","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China"},{"name":"MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1046","DOI":"10.1093\/gbe\/evu079","article-title":"Comparative Genomic Analysis and Virulence Differences in Closely Related Salmonella enterica Serotype Heidelberg Isolates from Humans, Retail Meats, and Animals","volume":"6","author":"Hoffmann","year":"2014","journal-title":"Genome Biol. 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