The role of buffers in wild-type HEWL amyloid fibril formation mechanism

Brudar, Sandi (author), Hribar-Lee, Barbara (author)

Amyloid fibrils, highly ordered protein aggregates, play an important role in the onset of several neurological disorders. Many studies have assessed amyloid fibril formation under specific solution conditions, but they all lack an important phenomena in biological solutions—buffer specific effects. We have focused on the formation of hen egg-white lysozyme (HEWL) fibrils in aqueous solutions of different buffers in both acidic and basic pH range. By means of UV-Vis spectroscopy, fluorescence measurements and CD spectroscopy, we have managed to show that fibrillization of HEWL is affected by buffer identity (glycine, TRIS, phosphate, KCl-HCl, cacodylate, HEPES, acetate), solution pH, sample incubation (agitated vs. static) and added excipients (NaCl and PEG). HEWL only forms amyloid fibrils at pH = 2.0 under agitated conditions in glycine and KCl-HCl buffers of high enough ionic strength. Phosphate buffer on the other hand stabilizes the HEWL molecules. Similar stabilization effect was achieved by addition of PEG12000 molecules to the solution.

• Language: English
• Keywords: lysozyme, amyloid fibrils, buffer-specific effects
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2019
• Number of pages: 18 str.
• Numbering: Vol. 9, iss. 2, art. 65
• PID: 20.500.12556/RUL-125374
• UDC: 577.322
• ISSN on article: 2218-273X
• DOI: 10.3390/biom9020065
• COBISS.SI-ID: 1538128835
• Publication date in RUL: 12.03.2021

Record is a part of a journal

• Title: Biomolecules
• Shortened title: Biomolecules
• Publisher: MDPI
• ISSN: 2218-273X
• COBISS.SI-ID: 519952921

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 12.03.2021

Secondary language

• Language: Slovenian
• Keywords: lizocim, amiloidne fibrile, pufer-specifični efekti

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P1-0201
• Name: Fizikalna kemija

• Funder: ARRS - Slovenian Research Agency
• Project number: BI-US/18-19-061