{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T02:39:04Z","timestamp":1775702344597,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,6,6]],"date-time":"2020-06-06T00:00:00Z","timestamp":1591401600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["OP1117728"],"award-info":[{"award-number":["OP1117728"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000265","name":"Medical Research Council","doi-asserted-by":"publisher","award":["MR\/M011569\/1"],"award-info":[{"award-number":["MR\/M011569\/1"]}],"id":[{"id":"10.13039\/501100000265","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000265","name":"Medical Research Council","doi-asserted-by":"publisher","award":["MR\/S004793\/1"],"award-info":[{"award-number":["MR\/S004793\/1"]}],"id":[{"id":"10.13039\/501100000265","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Jean Clayton Fund at Liverpool School of Tropical Medicine","award":["JC170627EN02"],"award-info":[{"award-number":["JC170627EN02"]}]},{"DOI":"10.13039\/501100000272","name":"National Institute for Health Research","doi-asserted-by":"publisher","award":["NIHR200632"],"award-info":[{"award-number":["NIHR200632"]}],"id":[{"id":"10.13039\/501100000272","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Pneumonia is the sixth largest cause of death in the UK. It is usually caused by Streptococcus pneumoniae, which healthy individuals can carry in their nose without symptoms of disease. Antimicrobial resistance further increases mortality and morbidity associated with pneumococcal infection, although few studies have analysed resistance in naturally circulating pneumococcal isolates in adult populations. Here, we report on the resistome and associated mobile genetic elements within circulating pneumococcus isolated from adult volunteers enrolled in the experimental human pneumococcal colonisation (EHPC) research program at the Liverpool School of Tropical Medicine, UK. Pneumococcal isolates collected from 30 healthy asymptomatic adults who had volunteered to take part in clinical research were screened for antibiotic susceptibility to erythromycin and tetracycline, and whole-genome sequenced. The genetic context of resistance to one or both antibiotics in four isolates was characterised bioinformatically, and any association of the resistance genes with mobile genetic elements was determined. Tetracycline and macrolide resistance genes [tet(M), erm(B), mef(A), msr(D)] were detected on known Tn916-like integrative and conjugative elements, namely Tn6002 and Tn2010, and tet(32) was found for the first time in S. pneumoniae located on a novel 50 kb genomic island. The widespread use of pneumococcal conjugate vaccines impacts on serotype prevalence and transmission within the community. It is therefore important to continue to monitor antimicrobial resistance (AMR) genes present in both vaccine types and non-vaccine types in response to contemporary antimicrobial therapies and characterise the genetic context of acquired resistance genes to continually optimise antibiotic therapies.<\/jats:p>","DOI":"10.3390\/genes11060625","type":"journal-article","created":{"date-parts":[[2020,6,9]],"date-time":"2020-06-09T06:34:16Z","timestamp":1591684456000},"page":"625","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Antibiotic Resistance Is Associated with Integrative and Conjugative Elements and Genomic Islands in Naturally Circulating Streptococcus pneumoniae Isolates from Adults in Liverpool, UK"],"prefix":"10.3390","volume":"11","author":[{"given":"Elissavet","family":"Nikolaou","sequence":"first","affiliation":[{"name":"Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alasdair T. M.","family":"Hubbard","sequence":"additional","affiliation":[{"name":"Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK"},{"name":"Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2771-2345","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Botelho","sequence":"additional","affiliation":[{"name":"Antibiotic Resistance Evolution Group, Max-Planck-Institute for Evolutionary Biology, 24306 Pl\u00f6n, Germany"},{"name":"Department of Evolutionary Ecology and Genetics, Christian-Albrechts-Universit\u00e4t zu Kiel, 24118 Kiel, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Taylor A. M.","family":"Marschall","sequence":"additional","affiliation":[{"name":"Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniela M.","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0760-3088","authenticated-orcid":false,"given":"Adam P.","family":"Roberts","sequence":"additional","affiliation":[{"name":"Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK"},{"name":"Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"893","DOI":"10.1016\/S0140-6736(09)61204-6","article-title":"Burden of disease caused by Streptococcus pneumoniae in children younger than 5 years: Global estimates","volume":"374","author":"Wolfson","year":"2009","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1136\/thx.2009.129502","article-title":"Clinical and economic burden of community-acquired pneumonia among adults in Europe","volume":"67","author":"Welte","year":"2012","journal-title":"Thorax"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"387","DOI":"10.1086\/431524","article-title":"Antibody responses to nasopharyngeal carriage of S. pneumoniae in adults: A longitudinal household study","volume":"192","author":"Goldblatt","year":"2005","journal-title":"J. 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