{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T16:27:07Z","timestamp":1786465627997,"version":"build-2736575974"},"reference-count":36,"publisher":"SAGE Publications","issue":"10","license":[{"start":{"date-parts":[[2021,10,1]],"date-time":"2021-10-01T00:00:00Z","timestamp":1633046400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Microbial Drug Resistance"],"published-print":{"date-parts":[[2021,10]]},"abstract":"\n Linezolid (LNZ) is one of the most important antimicrobial agents against infections caused by gram-positive bacteria, including enterococci. In a layer operation system, antimicrobial resistance can be transferred to commercial layers via the fecal-oral route. This study investigated the presence and distribution of LNZ-resistant\n Enterococcus faecalis<\/jats:italic>\n and\n Enterococcus faecium<\/jats:italic>\n in a layer operation system. Among 117\n E. faecalis<\/jats:italic>\n and 154\n E. faecium<\/jats:italic>\n , 10 (8.5%)\n E. faecalis<\/jats:italic>\n and 5 (3.2%)\n E. faecium<\/jats:italic>\n isolates showed resistance to LNZ and chloramphenicol, and they exhibited multidrug resistance against 5 or more classes of antimicrobial agents. Among the resistant isolates, 9 (90.0%) and 2 (20.0%)\n E. faecalis<\/jats:italic>\n harbored\n optrA<\/jats:italic>\n and\n cfr<\/jats:italic>\n genes, respectively. The\n optrA<\/jats:italic>\n and\n fexA<\/jats:italic>\n genes were not detected in five LNZ-resistant\n E. faecium<\/jats:italic>\n . None of the 15 LNZ-resistant isolates harbored the\n fexA<\/jats:italic>\n gene, and no mutations were observed in the genes encoding domain V of 23S ribosomal RNA (rRNA) and ribosomal proteins L3 (\n rplC<\/jats:italic>\n ) and L4 (\n rplD<\/jats:italic>\n ). Transferability was identified in three of the nine\n optrA<\/jats:italic>\n -positive LNZ-resistant isolates. The\n tetM<\/jats:italic>\n ,\n tetL<\/jats:italic>\n , and\n ermB<\/jats:italic>\n genes were cotransferred with the\n optrA<\/jats:italic>\n gene in all\n optrA<\/jats:italic>\n -positive transconjugants. The results indicate that\n optrA<\/jats:italic>\n is well-distributed in\n E. faecalis<\/jats:italic>\n , implying a greater level of transferability. Thus, enhanced surveillance efforts are needed to monitor the emergence and spread of\n optrA<\/jats:italic>\n in enterococci in layer operation system.\n <\/jats:p>","DOI":"10.1089\/mdr.2020.0028","type":"journal-article","created":{"date-parts":[[2021,7,23]],"date-time":"2021-07-23T16:57:41Z","timestamp":1627059461000},"page":"1443-1449","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":6,"title":["Detection of Linezolid-Resistant\n Enterococcus faecalis<\/i>\n and\n Enterococcus faecium<\/i>\n Isolates from the Layer Operation System in Korea"],"prefix":"10.1177","volume":"27","author":[{"given":"Yeong Bin","family":"Kim","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu, Republic of Korea."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sunghyun","family":"Yoon","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu, Republic of Korea."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kwang Won","family":"Seo","sequence":"additional","affiliation":[{"name":"Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, Mississippi State, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jong Bo","family":"Shim","sequence":"additional","affiliation":[{"name":"Korean Poultry TS Co., Ltd., Incheon, Republic of Korea."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eun Bi","family":"Noh","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu, Republic of Korea."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Young Ju","family":"Lee","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu, Republic of Korea."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2021,10,14]]},"reference":[{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.drup.2014.04.002"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.3904\/kjm.2018.93.5.464"},{"key":"e_1_3_4_4_2","author":"Torres C.","year":"2018","unstructured":"Torres C., , Alonso C.A, , Ruiz-Ripa L., , Le\u00f3n-Sampedro R., , Del Campo R., , and Coque T.M.. 2018. Antimicrobial resistance in Enterococcus spp. of animal origin. Microbiol. Spectr. 6. DOI: 10.1128\/microbiolspec.ARBA-0032-2018.","journal-title":"Enterococcus"},{"key":"e_1_3_4_5_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.00419-12"},{"key":"e_1_3_4_6_2","doi-asserted-by":"crossref","first-page":"1466","DOI":"10.1093\/jac\/dkw016","article-title":"Genetic environment of the transferable oxazolidinone\/phenicol resistance gene optrA in Enterococcus faecalis isolates of human and animal origin","volume":"71","author":"He T.","year":"2016","unstructured":"He T., , Shen Y., , Schwarz S., et al. 2016. Genetic environment of the transferable oxazolidinone\/phenicol resistance gene optrA in Enterococcus faecalis isolates of human and animal origin. J. Antimicrob. Chemother. 71:1466\u20131473.","journal-title":"J. Antimicrob. Chemother"},{"key":"e_1_3_4_7_2","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1093\/jac\/dkz419","article-title":"From farm to fork: identical clones and Tn6674-like elements in linezolid-resistant Enterococcus faecalis from food-producing animals and retail meat","volume":"75","author":"Elghaieb H.","year":"2020","unstructured":"Elghaieb H., , Tedim A.P, , Abbassi M.S, et al. 2020. From farm to fork: identical clones and Tn6674-like elements in linezolid-resistant Enterococcus faecalis from food-producing animals and retail meat. J. Antimicrob. Chemother. 75:30\u201335.","journal-title":"J. Antimicrob. Chemother"},{"key":"e_1_3_4_8_2","doi-asserted-by":"publisher","DOI":"10.1093\/jac\/dkv116"},{"key":"e_1_3_4_9_2","first-page":"678","article-title":"Detection of linezolid resistance due to the optrA gene in Enterococcus faecalis from poultry meat from the American continent (Colombia)","volume":"72","author":"Cavaco L.M.","year":"2017","unstructured":"Cavaco L.M., , Bernal J.F, , Zankari E., et al. 2017. Detection of linezolid resistance due to the optrA gene in Enterococcus faecalis from poultry meat from the American continent (Colombia). J. Antimicrob. Chemother. 72:678\u2013683.","journal-title":"J. Antimicrob. Chemother"},{"key":"e_1_3_4_10_2","doi-asserted-by":"crossref","first-page":"252","DOI":"10.1016\/j.vetmic.2017.01.035","article-title":"Detection of novel oxazolidinone and phenicol resistance gene optrA in enterococcal isolates from food animals and animal carcasses","volume":"201","author":"Tamang M.D.","year":"2017","unstructured":"Tamang M.D., , Moon D.C, , Kim S.R, et al. 2017. Detection of novel oxazolidinone and phenicol resistance gene optrA in enterococcal isolates from food animals and animal carcasses. Vet. Microbiol. 201:252\u2013256.","journal-title":"Vet. Microbiol"},{"key":"e_1_3_4_11_2","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/j.ijfoodmicro.2019.01.002","article-title":"Detection of oxazolidinone and phenicol resistant enterococcal isolates from duck feces and carcasses","volume":"293","author":"Na S.H.","year":"2019","unstructured":"Na S.H., , Moon D.C, , Choi M.J, et al. 2019. Detection of oxazolidinone and phenicol resistant enterococcal isolates from duck feces and carcasses. Int. J. Food Microbiol. 293:53\u201359.","journal-title":"Int. J. Food Microbiol"},{"key":"e_1_3_4_12_2","doi-asserted-by":"publisher","DOI":"10.4315\/0362-028X.JFP-10-451"},{"key":"e_1_3_4_13_2","first-page":"986","volume":"96","author":"Nowakiewicz A.","year":"2017","unstructured":"Nowakiewicz A., , Zi\u00f3lkowska G., , Troscianczyk A., , Zieba P., , and Gnat S.. 2017. Determination of resistance and virulence genes in Enterococcus faecalis and E. faecium strains isolated from poultry and their genotypic characterization by ADSRRS-fingerprinting. Poult. Sci. 96:986\u2013996.","journal-title":"Determination of resistance and virulence genes in Enterococcus faecalis and E. faecium strains isolated from poultry and their genotypic characterization by ADSRRS-fingerprinting. Poult. Sci"},{"key":"e_1_3_4_14_2","volume-title":"Enterococcus faecalis","author":"Kim Y.B.","unstructured":"Kim Y.B., , Seo K.W, , Shim J.B, , Son S.H, , Noh E.B, , and Lee Y.J. 2019. Molecular characterization of antimicrobial-resistant Enterococcus faecalis and Enterococcus faecium isolated from layer parent stock. Poult. Sci. 98:5892\u20135899."},{"key":"e_1_3_4_15_2","doi-asserted-by":"crossref","first-page":"1472","DOI":"10.3382\/ps\/pey513","article-title":"Comparative genetic characterization of third-generation cephalosporin-resistant Escherichia coli isolated from a layer operation system in Korea","volume":"98","author":"Seo K.W.","year":"2019","unstructured":"Seo K.W., , Shim J.B, , and Lee Y.J.. 2019. Comparative genetic characterization of third-generation cephalosporin-resistant Escherichia coli isolated from a layer operation system in Korea. Poult. Sci. 98:1472\u20131479.","journal-title":"Poult. Sci"},{"key":"e_1_3_4_16_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1371\/journal.pone.0121189","article-title":"Unraveling antimicrobial resistance genes and phenotype patterns among Enterococcus faecalis isolated from retail chicken products in Japan","volume":"10","author":"Hidano A.","year":"2015","unstructured":"Hidano A., , Yamamoto T., , Hayama Y., et al. 2015. Unraveling antimicrobial resistance genes and phenotype patterns among Enterococcus faecalis isolated from retail chicken products in Japan. PLoS One, 10:1\u201315.","journal-title":"PLoS One"},{"key":"e_1_3_4_17_2","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/j.vetmic.2018.02.012","article-title":"High diversity of genes and plasmids encoding resistance to third-generation cephalosporins and quinolones in clinical Escherichia coli from commercial poultry flocks in Italy","volume":"216","author":"Niero G.","year":"2018","unstructured":"Niero G., , Bortolaia V., , Vanni M., , Intorre L., , Guardabassi L., , and Piccirillo A.. 2018. High diversity of genes and plasmids encoding resistance to third-generation cephalosporins and quinolones in clinical Escherichia coli from commercial poultry flocks in Italy. Vet. Microbiol. 216:93\u201398.","journal-title":"Vet. Microbiol"},{"key":"e_1_3_4_18_2","doi-asserted-by":"publisher","DOI":"10.3382\/ps\/pey545"},{"key":"e_1_3_4_19_2","unstructured":"United States Department of Agriculture (USDA). 2012. National Poultry Improvement Plan and Auxiliary Provisions. APHIS Publication. 91-55-088. United States Department of Agriculture (USDA) Washington DC."},{"key":"e_1_3_4_20_2","first-page":"Gimcheon","article-title":"National Antimicrobial Resistance Monitoring Program","author":"Animal and Plant Quarantine Agency (APQA)","year":"2018","unstructured":"Animal and Plant Quarantine Agency (APQA). 2018. National Antimicrobial Resistance Monitoring Program. Animal and Plant Quarantine Agency (APQA), Gimcheon.","journal-title":"Animal and Plant Quarantine Agency"},{"key":"e_1_3_4_21_2","doi-asserted-by":"publisher","DOI":"10.1128\/jcm.33.1.24-27.1995"},{"key":"e_1_3_4_22_2","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1016\/S0168-6496(99)00073-2","article-title":"Competitive polymerase chain reaction for quantification of nonculturable Enterococcus faecalis cells in lake water","volume":"30","author":"del Mar Lle\u00f3 M.","year":"2006","unstructured":"del Mar Lle\u00f3 M., , Tafi M.C, , Signoretto C., , Dal Cero C., , and Canepari P.. 2006. Competitive polymerase chain reaction for quantification of nonculturable Enterococcus faecalis cells in lake water. FEMS Microbiol. Ecol. 30:345\u2013353.","journal-title":"FEMS Microbiol. Ecol"},{"key":"e_1_3_4_23_2","unstructured":"Clinical and Laboratory Standards Institute (CLSI). 2018. Performance Standards for Antimicrobial Susceptibility Testing M100-S23. Clinical and Laboratory Standards Institute Wayne PA."},{"key":"e_1_3_4_24_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.50.4.1156-1163.2006"},{"key":"e_1_3_4_25_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.43.1.157"},{"key":"e_1_3_4_26_2","doi-asserted-by":"crossref","first-page":"1423","DOI":"10.1128\/AAC.47.4.1423-1426.2003","article-title":"Multiplex PCR for detection of aminoglycoside resistance genes in enterococci","volume":"47","author":"Vakulenko S.B.","year":"2013","unstructured":"Vakulenko S.B., , Donabedian S.M, , Voskresenskiy A.M, , Zervos M.J, , Lerner S.A, , and Chow J.W.. 2013. Multiplex PCR for detection of aminoglycoside resistance genes in enterococci. Antimicrob. Agents Chemother. 47:1423\u20131426.","journal-title":"Antimicrob. Agents Chemother"},{"key":"e_1_3_4_27_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1371\/journal.pone.0062838","article-title":"Aquaculture can promote the presence and spread of antibiotic-resistant enterococci in marine sediments","volume":"8","author":"Di Cesare A.","year":"2013","unstructured":"Di Cesare A., , Luna G.M, , Vignaroli C., et al. 2013. Aquaculture can promote the presence and spread of antibiotic-resistant enterococci in marine sediments. PLoS One, 8:1\u20138.","journal-title":"PLoS One"},{"key":"e_1_3_4_28_2","doi-asserted-by":"crossref","first-page":"476","DOI":"10.1007\/s00284-014-0742-1","article-title":"Transfer of tetracycline resistance genes with aggregation substance in food-borne Enterococcus faecalis","volume":"70","author":"Choi J.M.","year":"2015","unstructured":"Choi J.M., , and Woo G.J.. 2015. Transfer of tetracycline resistance genes with aggregation substance in food-borne Enterococcus faecalis. Curr. Microbiol. 70:476\u2013484.","journal-title":"Curr. Microbiol"},{"key":"e_1_3_4_29_2","doi-asserted-by":"crossref","first-page":"1480","DOI":"10.1086\/513876","article-title":"Dose dependence of emergence of resistance to linezolid in Enterococcus faecalis in vivo","volume":"195","author":"Bourgeois-Nicolaos N.","year":"2007","unstructured":"Bourgeois-Nicolaos N., , Massias L., , Couson B., , Butel M., , Andremont A., , and Doucet-Populaire F.. 2007. Dose dependence of emergence of resistance to linezolid in Enterococcus faecalis in vivo. J. Infect. Dis. 195:1480\u20131488.","journal-title":"J. Infect. Dis"},{"key":"e_1_3_4_30_2","doi-asserted-by":"publisher","DOI":"10.1128\/AEM.00749-06"},{"key":"e_1_3_4_31_2","doi-asserted-by":"publisher","DOI":"10.3382\/ps\/pey477"},{"key":"e_1_3_4_32_2","doi-asserted-by":"publisher","DOI":"10.3382\/ps\/pez403"},{"key":"e_1_3_4_33_2","doi-asserted-by":"publisher","DOI":"10.1586\/14787210.2014.956092"},{"key":"e_1_3_4_34_2","author":"Zhang Y.","unstructured":"Zhang Y., , Dong G., , Li J., et al. 2018. A high incidence and coexistence of multiresistance genes cfr and optrA among linezolid-resistant enterococci isolated from a teaching hospital in Wenzhou, China. Eur. J. Clin. Microbiol. Infect. Dis. 37:1441\u20131448.","journal-title":"Eur. J. Clin. Microbiol. Infect"},{"key":"e_1_3_4_35_2","doi-asserted-by":"crossref","first-page":"1650","DOI":"10.1128\/AAC.06091-11","article-title":"First report of the multidrug resistance gene cfr in Enterococcus faecalis of animal origin","volume":"56","author":"Liu Y.","year":"2012","unstructured":"Liu Y., , Wang Y., , Wu C., et al. 2012. First report of the multidrug resistance gene cfr in Enterococcus faecalis of animal origin. Antimicrob. Agents Chemother. 56:1650\u20131654.","journal-title":"Antimicrob. Agents Chemother"},{"key":"e_1_3_4_36_2","author":"Cai J.","year":"2015","unstructured":"Cai J., , Wang Y., , Schwarz S., et al. 2015. Enterococcal isolates carrying the novel oxazolidinone resistance gene optrA from hospitals in Zhejiang, Guangdong, and Henan, China, 2010-2014. Clin. Microbiol. Infect. 21:1095.e1\u20131095.e4.","journal-title":"et al"},{"key":"e_1_3_4_37_2","doi-asserted-by":"crossref","first-page":"2397","DOI":"10.2147\/IDR.S181339","article-title":"Epidemiological characteristics and genetic structure of linezolid-resistant Enterococcus faecalis","volume":"11","author":"Chen M.","year":"2018","unstructured":"Chen M., , Pan H., , Lou Y., et al. 2018. Epidemiological characteristics and genetic structure of linezolid-resistant Enterococcus faecalis. Infect. Drug Resist. 11:2397\u20132409.","journal-title":"Infect. Drug Resist"}],"container-title":["Microbial Drug Resistance"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1089\/mdr.2020.0028","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1089\/mdr.2020.0028","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1089\/mdr.2020.0028","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T20:37:28Z","timestamp":1777667848000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/full\/10.1089\/mdr.2020.0028"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,10]]},"references-count":36,"journal-issue":{"issue":"10","published-print":{"date-parts":[[2021,10]]}},"alternative-id":["10.1089\/mdr.2020.0028"],"URL":"https:\/\/doi.org\/10.1089\/mdr.2020.0028","relation":{},"ISSN":["1076-6294","1931-8448"],"issn-type":[{"value":"1076-6294","type":"print"},{"value":"1931-8448","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,10]]}}}