{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T22:09:59Z","timestamp":1785362999368,"version":"3.55.0"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,11,14]],"date-time":"2022-11-14T00:00:00Z","timestamp":1668384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>(1) Background: Linezolid plays an important role in the treatment of invasive infections caused by vancomycin-resistant enterococci after its introduction to clinical practice. However, a detailed examination of linezolid-nonsusceptible enterococci (LNSE) is required. In this study, we attempted to analyze the mechanisms of LNSE strains isolated from a tertiary care hospital. (2) Methods: From 2019 to 2020, 18 Enterococcus faecalis, 14 E. faecium, and 2 E. gallinarum clinical isolates were collected at Severance Hospital. Agar dilution was performed to evaluate precise linezolid minimum inhibitory concentrations (MICs). Short-read whole-genome sequencing (WGS) was used to analyze resistance determinants. (3) Results: The presence of the optrA gene was likely the primary resistance mechanism in these three species, typically demonstrating a MIC value of 8 \u03bcg\/mL. The co-existence of the cfr(D) and poxtA2 gene was the second major mechanism, primarily predicting a phenotype showing intermediate susceptibility to linezolid. G2576U mutation on 23S rRNA was only found in E. faecium; it mediated the most significant increase in linezolid MIC. (4) Conclusion: This is the first report examining poxtA2\u2013cfr(D) co-harboring clinical enterococcal isolates in Korea and demonstrating the poxtA EF9F6-harboring clinical E. gallinarum strain worldwide. The comparison with resistance-gene-containing fragments in the isolates obtained from different countries and different sources demonstrated the spread of linezolid-resistance genes and suggested the possibility of foodborne transmission.<\/jats:p>","DOI":"10.3390\/antibiotics11111624","type":"journal-article","created":{"date-parts":[[2022,11,15]],"date-time":"2022-11-15T02:28:58Z","timestamp":1668479338000},"page":"1624","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Prevalence and Genetic Analysis of Resistance Mechanisms of Linezolid-Nonsusceptible Enterococci in a Tertiary Care Hospital Examined via Whole-Genome Sequencing"],"prefix":"10.3390","volume":"11","author":[{"given":"Yuxin","family":"Hu","sequence":"first","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dongju","family":"Won","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6123-5426","authenticated-orcid":false,"given":"Le Phuong","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"},{"name":"Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 03722, Republic of Korea"},{"name":"Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0840-3512","authenticated-orcid":false,"given":"Kennedy Mensah","family":"Osei","sequence":"additional","affiliation":[{"name":"Department of Laboratory Services, Tamale Teaching Hospital, Tamale 41965, Ghana"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Younghee","family":"Seo","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junglim","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoonhee","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8523-4126","authenticated-orcid":false,"given":"Hyukmin","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1225-8477","authenticated-orcid":false,"given":"Dongeun","family":"Yong","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"},{"name":"Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jong Rak","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyungwon","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul 03722, Republic of Korea"},{"name":"Seoul Clinical Laboratories Academy, Yongin 16954, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e00181-19","DOI":"10.1128\/CMR.00181-19","article-title":"Antimicrobial Resistance in ESKAPE Pathogens","volume":"33","author":"Forde","year":"2020","journal-title":"Clin. 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