{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T02:49:36Z","timestamp":1791946176656,"version":"4.3.4"},"reference-count":46,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,17]],"date-time":"2021-11-17T00:00:00Z","timestamp":1637107200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004504","name":"Lietuvos Mokslo Taryba","doi-asserted-by":"publisher","award":["S-SEN-20-3"],"award-info":[{"award-number":["S-SEN-20-3"]}],"id":[{"id":"10.13039\/501100004504","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Protein aggregate formation is linked with multiple amyloidoses, including Alzheimer\u2018s and Parkinson\u2018s diseases. Currently, the understanding of such fibrillar structure formation and propagation is still not sufficient, the outcome of which is a lack of potent, anti-amyloid drugs. The environmental conditions used during in vitro protein aggregation assays play an important role in determining both the aggregation kinetic parameters, as well as resulting fibril structure. In the case of alpha-synuclein, ionic strength has been shown as a crucial factor in its amyloid aggregation. In this work, we examine a large sample size of alpha-synuclein aggregation reactions under thirty different ionic strength and protein concentration combinations and determine the resulting fibril structural variations using their dye-binding properties, secondary structure and morphology. We show that both ionic strength and protein concentration determine the structural variability of alpha-synuclein amyloid fibrils and that sometimes even identical conditions can result in up to four distinct types of aggregates.<\/jats:p>","DOI":"10.3390\/ijms222212382","type":"journal-article","created":{"date-parts":[[2021,11,17]],"date-time":"2021-11-17T02:42:28Z","timestamp":1637116948000},"page":"12382","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":69,"title":["Polymorphism of Alpha-Synuclein Amyloid Fibrils Depends on Ionic Strength and Protein Concentration"],"prefix":"10.3390","volume":"22","author":[{"given":"Mantas","family":"Ziaunys","sequence":"first","affiliation":[{"name":"Institute of Biotechnology, Life Sciences Centre, Vilnius University, 10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2715-067X","authenticated-orcid":false,"given":"Andrius","family":"Sakalauskas","sequence":"additional","affiliation":[{"name":"Institute of Biotechnology, Life Sciences Centre, Vilnius University, 10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kamile","family":"Mikalauskaite","sequence":"additional","affiliation":[{"name":"Institute of Biotechnology, Life Sciences Centre, Vilnius University, 10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1829-5455","authenticated-orcid":false,"given":"Vytautas","family":"Smirnovas","sequence":"additional","affiliation":[{"name":"Institute of Biotechnology, Life Sciences Centre, Vilnius University, 10257 Vilnius, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3","DOI":"10.14797\/mdcj-8-3-3","article-title":"The Amyloidoses: Clinical Features, Diagnosis and Treatment","volume":"8","author":"Baker","year":"2012","journal-title":"Methodist Debakey Cardiovasc. 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