{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T02:23:39Z","timestamp":1792635819625,"version":"4.5.0"},"reference-count":55,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,3,16]],"date-time":"2021-03-16T00:00:00Z","timestamp":1615852800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["RTG2157, RTG2581"],"award-info":[{"award-number":["RTG2157, RTG2581"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001655","name":"Deutscher Akademischer Austauschdienst","doi-asserted-by":"publisher","award":["STIBET Fellowship"],"award-info":[{"award-number":["STIBET Fellowship"]}],"id":[{"id":"10.13039\/501100001655","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:p>Expansion Microscopy (ExM) is a novel tool improving the resolution of fluorescence microscopy by linking the sample into a hydrogel that gets physically expanded in water. Previously, we have used ExM to visualize the intracellular Gram-negative pathogens <jats:italic>Chlamydia trachomatis<\/jats:italic>, <jats:italic>Simkania negevensis<\/jats:italic>, and <jats:italic>Neisseria gonorrhoeae<\/jats:italic>. Gram-positive bacteria have a rigid and thick cell wall that impedes classic expansion strategies. Here we developed an approach, which included a series of enzymatic treatments resulting in isotropic 4\u00d7 expansion of the Gram-positive pathogen <jats:italic>Staphylococcus aureus.<\/jats:italic> We further demonstrate the suitability of the technique for imaging of planktonic bacteria as well as endocytosed, intracellular bacteria at a spatial resolution of approximately 60 nm with conventional confocal laser scanning microscopy.<\/jats:p>","DOI":"10.3389\/fcimb.2021.644750","type":"journal-article","created":{"date-parts":[[2021,3,16]],"date-time":"2021-03-16T06:15:21Z","timestamp":1615875321000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":21,"title":["The Expandables: Cracking the Staphylococcal Cell Wall for Expansion Microscopy"],"prefix":"10.3389","volume":"11","author":[{"given":"Tobias C.","family":"Kunz","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcel","family":"R\u00fchling","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriana","family":"Moldovan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kerstin","family":"Paprotka","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vera","family":"Kozjak-Pavlovic","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Rudel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Fraunholz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,3,16]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1139","DOI":"10.3390\/ph3041139","article-title":"Lysostaphin: A Staphylococcal Bacteriolysin with Potential Clinical Applications","volume":"3","author":"Bastos","year":"2010","journal-title":"Pharm. 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