title: Binding of Thioflavin-T to Amyloid Fibrils Leads to Fluorescence Self-Quenching and Fibril Compaction.
abstract: Thioflavin-T binds to and detects amyloid fibrils via fluorescence enhancement. Using a combination of linear dichroism and fluorescence spectroscopies, we report that the relation between the emission intensity and binding of thioflavin-T to insulin fibrils is nonlinear and discuss this in relation to its use in kinetic assays. We demonstrate, from fluorescence lifetime recordings, that the nonlinearity is due to thioflavin-T being sensitive to self-quenching. In addition, thioflavin-T can induce fibril compaction but not alter fibril structure. Our work underscores the photophysical complexity of thioflavin-T and the necessity of calibrating the linear range of its emission response for quantitative in vitro studies.
authors.affiliation: Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology , Kemivägen 10, 412 96 Gothenburg, Sweden.
authors.forename: David J
authors.identifier: 0000-0002-8501-801X
authors.initials: DJ
authors.lastname: Lindberg
authors.affiliation: Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology , Kemivägen 10, 412 96 Gothenburg, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Wenger
authors.affiliation: Division of Chemistry and Biochemistry, Department of Chemistry and Chemical Engineering, Chalmers University of Technology , Kemivägen 10, 412 96 Gothenburg, Sweden.
authors.forename: Elin
authors.initials: E
authors.lastname: Sundin
authors.affiliation: Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology , Kemivägen 10, 412 96 Gothenburg, Sweden.
authors.forename: Emelie
authors.initials: E
authors.lastname: Wesén
authors.affiliation: Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology , Kemivägen 10, 412 96 Gothenburg, Sweden.
authors.forename: Fredrik
authors.identifier: 0000-0002-4767-4868
authors.initials: F
authors.lastname: Westerlund
authors.affiliation: Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology , Kemivägen 10, 412 96 Gothenburg, Sweden.
authors.forename: Elin K
authors.identifier: 0000-0002-1253-6342
authors.initials: EK
authors.lastname: Esbjörner
mesh_terms: D000682:Amyloid / Q000378:metabolism*; D052160:Benzothiazoles; D005456:Fluorescent Dyes; D011485:Protein Binding; D017510:Protein Folding; D013050:Spectrometry, Fluorescence; D013844:Thiazoles / Q000378:metabolism*
chemical_list: D000682:Amyloid; D052160:Benzothiazoles; D005456:Fluorescent Dyes; D013844:Thiazoles; C009462:thioflavin T