{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T08:24:05Z","timestamp":1770884645359,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T00:00:00Z","timestamp":1637280000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UID\/EQU\/00511\/2019"],"award-info":[{"award-number":["UID\/EQU\/00511\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["POCI-01-0145-FEDER-006939"],"award-info":[{"award-number":["POCI-01-0145-FEDER-006939"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/129312\/2017"],"award-info":[{"award-number":["SFRH\/BD\/129312\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["CEECINST\/00049\/2018"],"award-info":[{"award-number":["CEECINST\/00049\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Alzheimer\u2019s Association","award":["AARGD-18-566576"],"award-info":[{"award-number":["AARGD-18-566576"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Parkinson\u2019s disease (PD) is the second most common neurodegenerative disorder. An important hallmark of PD involves the pathological aggregation of proteins in structures known as Lewy bodies. The major component of these proteinaceous inclusions is alpha (\u03b1)-synuclein. In different conditions, \u03b1-synuclein can assume conformations rich in either \u03b1-helix or \u03b2-sheets. The mechanisms of \u03b1-synuclein misfolding, aggregation, and fibrillation remain unknown, but it is thought that \u03b2-sheet conformation of \u03b1-synuclein is responsible for its associated toxic mechanisms. To gain fundamental insights into the process of \u03b1-synuclein misfolding and aggregation, the secondary structure of this protein in the presence of charged and non-charged surfactant solutions was characterized. The selected surfactants were (anionic) sodium dodecyl sulphate (SDS), (cationic) cetyltrimethylammonium chloride (CTAC), and (uncharged) octyl \u03b2-D-glucopyranoside (OG). The effect of surfactants in \u03b1-synuclein misfolding was assessed by ultra-structural analyses, in vitro aggregation assays, and secondary structure analyses. The \u03b1-synuclein aggregation in the presence of negatively charged SDS suggests that SDS-monomer complexes stimulate the aggregation process. A reduction in the electrostatic repulsion between N- and C-terminal and in the hydrophobic interactions between the NAC (non-amyloid beta component) region and the C-terminal seems to be important to undergo aggregation. Fourier transform infrared spectroscopy (FTIR) measurements show that \u03b2-sheet structures comprise the assembly of the fibrils.<\/jats:p>","DOI":"10.3390\/ijms222212509","type":"journal-article","created":{"date-parts":[[2021,11,21]],"date-time":"2021-11-21T20:58:21Z","timestamp":1637528301000},"page":"12509","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["(De)stabilization of Alpha-Synuclein Fibrillary Aggregation by Charged and Uncharged Surfactants"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9841-3967","authenticated-orcid":false,"given":"Joana Ang\u00e9lica","family":"Loureiro","sequence":"first","affiliation":[{"name":"LEPABE, Department of Chemical Engineering, Faculty of Engineering of the University of Porto, 4200-465 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"St\u00e9phanie","family":"Andrade","sequence":"additional","affiliation":[{"name":"LEPABE, Department of Chemical Engineering, Faculty of Engineering of the University of Porto, 4200-465 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lies","family":"Goderis","sequence":"additional","affiliation":[{"name":"Faculty of Pharmaceutical Sciences, Ghent University, Sint-Pietersnieuwstraat 25, B-9000 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruben","family":"Gomez-Gutierrez","sequence":"additional","affiliation":[{"name":"Department of Neurology, The University of Texas Health Science Centre at Houston, Houston, TX 77030, USA"},{"name":"Department of Cell Biology, University of Malaga, 29071 Malaga, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claudio","family":"Soto","sequence":"additional","affiliation":[{"name":"Department of Neurology, The University of Texas Health Science Centre at Houston, Houston, TX 77030, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rodrigo","family":"Morales","sequence":"additional","affiliation":[{"name":"Department of Neurology, The University of Texas Health Science Centre at Houston, Houston, TX 77030, USA"},{"name":"CIBQA, Universidad Bernardo O\u2019Higgins, Santiago 1497, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8505-3432","authenticated-orcid":false,"given":"Maria Carmo","family":"Pereira","sequence":"additional","affiliation":[{"name":"LEPABE, Department of Chemical Engineering, Faculty of Engineering of the University of Porto, 4200-465 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1096\/fj.03-0338rev","article-title":"Alpha-synuclein and Parkinson\u2019s disease","volume":"18","author":"Recchia","year":"2004","journal-title":"FASEB J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.parkreldis.2009.08.007","article-title":"A timeline for Parkinson\u2019s disease","volume":"16","author":"Hawkes","year":"2010","journal-title":"Park. 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