{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T14:44:42Z","timestamp":1787582682633,"version":"build-2736575974"},"reference-count":24,"publisher":"The Royal Society","issue":"7","license":[{"start":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T00:00:00Z","timestamp":1784073600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Carlos Chagas Foundation"},{"name":"Brazilian National Council for Scientific and Technological Development"},{"DOI":"10.13039\/501100013275","name":"Serrapilheira Institute","doi-asserted-by":"crossref","award":["R-2012-37959"],"award-info":[{"award-number":["R-2012-37959"]}],"id":[{"id":"10.13039\/501100013275","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100004809","name":"FINEP","doi-asserted-by":"crossref","award":["01.22.0208.00"],"award-info":[{"award-number":["01.22.0208.00"]}],"id":[{"id":"10.13039\/501100004809","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,7,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The presence of lipopolysaccharide (LPS) contaminant from the vector expression bacteria Escherichia coli was described as a factor responsible for accelerating the in vitro fibrillation of recombinant \u03b1-synuclein (\u03b1S), a key protein involved in the neuropathogenesis of Parkinson's disease. Herein, we describe an efficient protocol for the removal of LPS from \u03b1S samples based on phase separation using Triton X-114. Importantly, this method was more feasible, faster and cheaper in eliminating LPS than the commercially available protocol using an affinity matrix of modified polymyxin B. Endotoxin-free \u03b1S (\u03b1SLPS-free) and the protein purified by a commonly used method (\u03b1Sc) were evaluated in terms of the kinetics of fibrillation, the microstructure of the aggregates and their susceptibility to certain inhibitors of fibrillation. Monomeric \u03b1Sc and \u03b1SLPS-free exhibit quite different susceptibility to modulators of the fibrillation process, despite their fibrils having similar morphologies and thickness according to the atomic force microscopy analysis. Unlike \u03b1Sc, the fibrillation of \u03b1SLPS-free was poorly inhibited to low concentrations of rosmarinic acid or baicalein. On the other hand, \u03b1SLPS-free, but not \u03b1Sc, had its fibrillation accelerated by harman and rifampicin. Collectively, these results highlight that the presence of LPS might generate artefacts regarding the in vitro screening of fibrillation modulators.<\/jats:p>","DOI":"10.1098\/rsob.260046","type":"journal-article","created":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T00:09:18Z","timestamp":1784074158000},"source":"Crossref","is-referenced-by-count":0,"title":["Removing the noise: endotoxin-free \u03b1-synuclein for accurate\n                    <i>in vitro<\/i>\n                    screening of fibrillation modulators"],"prefix":"10.1098","volume":"16","author":[{"given":"Julia","family":"Flor","sequence":"first","affiliation":[{"name":"Laboratory of Biological Chemistry of Neurodegenerative Disorders, Department of Physical Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ) 1 , Rio de Janeiro 21941-909, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Izecksohn","sequence":"additional","affiliation":[{"name":"Laboratory of Biological Chemistry of Neurodegenerative Disorders, Department of Physical Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ) 1 , Rio de Janeiro 21941-909, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Grasseschi","sequence":"additional","affiliation":[{"name":"Laboratory of Surface Coordination Chemistry of Nanomaterials (SuperNano), Department of Inorganic Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ) 2 , Rio de Janeiro 21941-909, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Magno","family":"Junqueira","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ) 3 , Rio de Janeiro 21941-909, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6178-0432","authenticated-orcid":false,"given":"Cristian","family":"Follmer","sequence":"additional","affiliation":[{"name":"Laboratory of Biological Chemistry of Neurodegenerative Disorders, Department of Physical Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ) 1 , Rio de Janeiro 21941-909, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"175","published-online":{"date-parts":[[2026,7,15]]},"reference":[{"key":"2026082410115758200_RSOB260046C1","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1146\/annurev-biochem-061516-045115","article-title":"Protein misfolding, amyloid formation, and human disease: a summary of progress over the last decade","volume":"86","author":"Chiti","year":"2017","journal-title":"Annu. Rev. Biochem."},{"key":"2026082410115758200_RSOB260046C2","doi-asserted-by":"crossref","first-page":"6469","DOI":"10.1073\/pnas.95.11.6469","article-title":"Alpha-synuclein in filamentous inclusions of Lewy bodies from Parkinson's disease and dementia with Lewy bodies","volume":"95","author":"Spillantini","year":"1998","journal-title":"Proc. Natl Acad. Sci. USA"},{"key":"2026082410115758200_RSOB260046C3","doi-asserted-by":"crossref","first-page":"S51","DOI":"10.3233\/JPD-179005","article-title":"The synucleinopathies: twenty years on","volume":"7","author":"Goedert","year":"2017","journal-title":"J. Parkinsons Dis."},{"key":"2026082410115758200_RSOB260046C4","doi-asserted-by":"crossref","first-page":"30891","DOI":"10.1038\/srep30891","article-title":"Exposure to bacterial endotoxin generates a distinct strain of \u03b1-synuclein fibril","volume":"6","author":"Kim","year":"2016","journal-title":"Sci. Rep."},{"key":"2026082410115758200_RSOB260046C5","doi-asserted-by":"crossref","first-page":"1151","DOI":"10.1111\/febs.17027","article-title":"Fibrillation of \u03b1-synuclein triggered by bacterial endotoxin and lipid vesicles is modulated by N-terminal acetylation and familial Parkinson's disease mutations","volume":"29","author":"Monteiro Neto","year":"2024","journal-title":"FEBS J."},{"key":"2026082410115758200_RSOB260046C6","doi-asserted-by":"crossref","first-page":"2915","DOI":"10.1021\/acschemneuro.0c00381","article-title":"Potential role of natural polyphenols against protein aggregation toxicity: in vitro, in vivo, and clinical studies","volume":"11","author":"Henr\u00edquez","year":"2020","journal-title":"ACS Chem. Neurosci."},{"key":"2026082410115758200_RSOB260046C7","doi-asserted-by":"crossref","first-page":"26846","DOI":"10.1074\/jbc.M403129200","article-title":"The flavonoid baicalein inhibits fibrillation of alpha-synuclein and disaggregates existing fibrils","volume":"279","author":"Zhu","year":"2004","journal-title":"J. Biol. Chem."},{"key":"2026082410115758200_RSOB260046C8","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1007\/978-3-319-18365-7_4","article-title":"Natural phenolic compounds as therapeutic and preventive agents for cerebral amyloidosis","volume":"863","author":"Yamada","year":"2015","journal-title":"Adv. Exp. Med. Biol."},{"key":"2026082410115758200_RSOB260046C9","doi-asserted-by":"crossref","first-page":"943","DOI":"10.1111\/jnc.13180","article-title":"Phenolic compounds prevent the oligomerization of \u03b1-synuclein and reduce synaptic toxicity","volume":"134","author":"Takahashi","year":"2015","journal-title":"J. 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