{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:50:01Z","timestamp":1760237401381,"version":"build-2065373602"},"reference-count":19,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,5,18]],"date-time":"2020-05-18T00:00:00Z","timestamp":1589760000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Fluids"],"abstract":"<jats:p>Multidrug resistant bacteria are one of the most serious public health threats nowadays. How bacteria, as a population, react to the presence of antibiotics is of major importance to the outcome of the chosen treatment. In this study we addressed the impact of oxacillin, a \u03b2-lactam, the most clinically relevant class of antibiotics, in the viscosity profile of the methicillin resistant Staphylococcus aureus (MRSA) strain COL. In the first approach, the antibiotic was added, at concentrations under the minimum inhibitory concentration (sub-MIC), to the culture of S. aureus and steady-state shear flow curves were obtained for discrete time points during the bacterial growth, with and without the presence of the antibiotic, showing distinct viscosity progress over time. The different behaviors obtained led us to test the impact of the sub-inhibitory concentration and a concentration that inhibited growth. In the second approach, the viscosity growth curves were measured at a constant shear rate of 10 s\u22121, over time. The obtained rheological behaviors revealed distinctive characteristics associated to the presence of each concentration of the tested antibiotic. These results bring new insights to the bacteria response to a well-known bacteriolytic antibiotic.<\/jats:p>","DOI":"10.3390\/fluids5020076","type":"journal-article","created":{"date-parts":[[2020,5,18]],"date-time":"2020-05-18T11:34:14Z","timestamp":1589801654000},"page":"76","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Antibiotic Activity Screened by the Rheology of S. aureus Cultures"],"prefix":"10.3390","volume":"5","author":[{"given":"Raquel","family":"Portela","sequence":"first","affiliation":[{"name":"UCIBIO@REQUIMTE, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Filipe","family":"Valcovo","sequence":"additional","affiliation":[{"name":"UCIBIO@REQUIMTE, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7356-8455","authenticated-orcid":false,"given":"Pedro L.","family":"Almeida","sequence":"additional","affiliation":[{"name":"\u00c1rea Departamental de F\u00edsica, ISEL\u2014Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, 1959-007 Lisboa, Portugal"},{"name":"CENIMAT\/I3N, Departamento de Ci\u00eancia dos Materiais, Faculdade Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Rita G.","family":"Sobral","sequence":"additional","affiliation":[{"name":"UCIBIO@REQUIMTE, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5871-4936","authenticated-orcid":false,"given":"Catarina R.","family":"Leal","sequence":"additional","affiliation":[{"name":"\u00c1rea Departamental de F\u00edsica, ISEL\u2014Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, 1959-007 Lisboa, Portugal"},{"name":"CENIMAT\/I3N, Departamento de Ci\u00eancia dos Materiais, Faculdade Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1093\/femsre\/fuu008","article-title":"Viscoelasticity of biofilms and their recalcitrance to mechanical and chemical challenges","volume":"39","author":"Peterson","year":"2015","journal-title":"FEMS Microbiol. 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