{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T07:07:20Z","timestamp":1789628840819,"version":"build-2803163510"},"reference-count":31,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,2,26]],"date-time":"2024-02-26T00:00:00Z","timestamp":1708905600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Gerencia Regional de Salud, Consejer\u00eda de Sanidad, Junta de Castilla y Le\u00f3n","award":["GRS 1831\/A\/18"],"award-info":[{"award-number":["GRS 1831\/A\/18"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Daptomycin is one of the last therapeutic resources for multidrug-resistant gram-positive bacteria. Despite its structural similarities with glycopeptides, its mechanisms of action and resistance are different and in some respects are not completely understood. Mutations in several genes have been associated with daptomycin resistance, especially in mprF, walkR, rpoB and rpoC, but their role and importance remain to be elucidated. We have studied mutations in 11 genes, which have been previously associated with daptomycin non-susceptibility, in nine daptomycin-non-susceptible Staphylococcus\u00a0aureus clinical isolates (daptomycin MIC: &gt;1 mg\/L). Susceptibility to daptomycin, vancomycin, linezolid, oxacillin, telavancin and dalbavancin was studied. walkR, agrA, cls1, cls2, fakA,\u00a0pnpA, clpP, prs, rpoB, rpoC and mprF were amplified by PCR and sequenced. The sequences were compared with the S. aureus ATCC 25923 complete genome (GenBank gi: 685631213) by using BLAST\u00ae software. We did not find any changes in walkR, pnpA, prs and clpP. All isolates excepting isolate MSa5 showed a high number of significant mutations (between 13 and 25 amino acid changes) in mprF. Most isolates also showed mutations in the rpo genes, the cls genes and fakA. Daptomycin non-susceptibility in S.\u00a0aureus clinical isolates seems to be reached through different mutation combinations when compared to S. aureus ATCC 25293. Especially mprF and cls1 showed very high polymorphism in most isolates. Meanwhile, one isolate, MSa5, showed only single mutation in mprF (P314T).<\/jats:p>","DOI":"10.3390\/pathogens13030206","type":"journal-article","created":{"date-parts":[[2024,2,26]],"date-time":"2024-02-26T10:40:17Z","timestamp":1708944017000},"page":"206","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Genomic Insights into Staphylococcus aureus Isolates Exhibiting Diminished Daptomycin Susceptibility"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6983-1895","authenticated-orcid":false,"given":"Natalia","family":"G\u00f3mez-Casanova","sequence":"first","affiliation":[{"name":"Research Group on Clinical Microbiology and Parasitology and Antimicrobial Resistance (IIMD-16), Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca (IBSAL), Universidad de Salamanca, CSIC, Hospital Universitario de Salamanca, 37007 Salamanca, Spain"},{"name":"Department of Biomedical and Diagnostic Sciences, Universidad de Salamanca, 37007 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M\u00aa Nieves","family":"Guti\u00e9rrez-Zufiaurre","sequence":"additional","affiliation":[{"name":"Research Group on Clinical Microbiology and Parasitology and Antimicrobial Resistance (IIMD-16), Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca (IBSAL), Universidad de Salamanca, CSIC, Hospital Universitario de Salamanca, 37007 Salamanca, Spain"},{"name":"Department of Microbiology and Parasitology, Hospital Universitario de Salamanca, 37007 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana M\u00aa","family":"Bl\u00e1zquez de Castro","sequence":"additional","affiliation":[{"name":"Research Group on Clinical Microbiology and Parasitology and Antimicrobial Resistance (IIMD-16), Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca (IBSAL), Universidad de Salamanca, CSIC, Hospital Universitario de Salamanca, 37007 Salamanca, Spain"},{"name":"Department of Microbiology and Parasitology, Hospital Universitario de Salamanca, 37007 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5981-8785","authenticated-orcid":false,"given":"Juan Luis","family":"Mu\u00f1oz-Bellido","sequence":"additional","affiliation":[{"name":"Research Group on Clinical Microbiology and Parasitology and Antimicrobial Resistance (IIMD-16), Instituto de Investigaci\u00f3n Biom\u00e9dica de Salamanca (IBSAL), Universidad de Salamanca, CSIC, Hospital Universitario de Salamanca, 37007 Salamanca, Spain"},{"name":"Department of Biomedical and Diagnostic Sciences, Universidad de Salamanca, 37007 Salamanca, Spain"},{"name":"Department of Microbiology and Parasitology, Hospital Universitario de Salamanca, 37007 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S10","DOI":"10.1086\/647938","article-title":"Daptomycin: From the mountain to the clinic, with essential help from Francis Tally, MD","volume":"50","author":"Eisenstein","year":"2010","journal-title":"Clin. 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