title: The role of initial oligomers in amyloid fibril formation by human stefin B.
abstract: Oligomers are commonly observed intermediates at the initial stages of amyloid fibril formation. They are toxic to neurons and cause decrease in neural transmission and long-term potentiation. We describe an in vitro study of the initial steps in amyloid fibril formation by human stefin B, which proved to be a good model system. Due to relative stability of the initial oligomers of stefin B, electrospray ionization mass spectrometry (ESI MS) could be applied in addition to size exclusion chromatography (SEC). These two techniques enabled us to separate and detect distinguished oligomers from the monomers: dimers, trimers, tetramers, up to decamers. The amyloid fibril formation process was followed at different pH and temperatures, including such conditions where the process was slow enough to detect the initial oligomeric species at the very beginning of the lag phase and those at the end of the lag phase. Taking into account the results of the lower-order oligomers transformations early in the process, we were able to propose an improved model for the stefin B fibril formation.
authors.affiliation: Department of Biochemistry, Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana 1000, Slovenia. peep.palumaa@ttu.ee.
authors.forename: Ajda
authors.initials: A
authors.lastname: Taler-Verčič
authors.forename: Tiina
authors.initials: T
authors.lastname: Kirsipuu
authors.forename: Merlin
authors.initials: M
authors.lastname: Friedemann
authors.forename: Andra
authors.initials: A
authors.lastname: Noormägi
authors.forename: Mira
authors.initials: M
authors.lastname: Polajnar
authors.forename: Julia
authors.initials: J
authors.lastname: Smirnova
authors.forename: Magda Tušek
authors.initials: MT
authors.lastname: Znidarič
authors.forename: Matjaž
authors.initials: M
authors.lastname: Zganec
authors.forename: Miha
authors.initials: M
authors.lastname: Skarabot
authors.forename: Andrej
authors.initials: A
authors.lastname: Vilfan
authors.forename: Rosemary A
authors.initials: RA
authors.lastname: Staniforth
authors.forename: Peep
authors.initials: P
authors.lastname: Palumaa
authors.forename: Eva
authors.initials: E
authors.lastname: Zerovnik
mesh_terms: D000682:Amyloid / Q000737:chemistry*; D055313:Cystatin B / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D055503:Protein Multimerization; D021241:Spectrometry, Mass, Electrospray Ionization; D013696:Temperature
chemical_list: D000682:Amyloid; D055313:Cystatin B