title: Immobilization of homogeneous monomeric, oligomeric and fibrillar Aβ species for reliable SPR measurements.
abstract: There is strong evidence that the amyloid-beta peptide (Aβ) plays a central role in the pathogenesis of Alzheimer's disease (AD). In this context, a detailed quantitative description of the interactions with different Aβ species is essential for characterization of physiological and artificial ligands. However, the high aggregation propensity of Aβ in concert with its susceptibility to structural changes due to even slight changes in solution conditions has impeded surface plasmon resonance (SPR) studies with homogeneous Aβ conformer species. Here, we have adapted the experimental procedures to state-of-the-art techniques and established novel approaches to reliably overcome the aforementioned challenges. We show that the application of density gradient centrifugation (DGC) for sample purification and the use of a single chain variable fragment (scFv) of a monoclonal antibody directed against the amino-terminus of Aβ allows reliable SPR measurements and quality control of the immobilized Aβ aggregate species at any step throughout the experiment.
authors.affiliation: Forschungszentrum Jülich, ICS-6 Structural Biochemistry, Jülich, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Frenzel
authors.affiliation: Forschungszentrum Jülich, ICS-6 Structural Biochemistry, Jülich, Germany.
authors.forename: Julian M
authors.initials: JM
authors.lastname: Glück
authors.affiliation: Forschungszentrum Jülich, ICS-6 Structural Biochemistry, Jülich, Germany; Heinrich-Heine-Universität Düsseldorf, Institut für Physikalische Biologie, Düsseldorf, Germany.
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Brener
authors.affiliation: Heinrich-Heine-Universität Düsseldorf, Institut für Physikalische Biologie, Düsseldorf, Germany.
authors.forename: Filipp
authors.initials: F
authors.lastname: Oesterhelt
authors.affiliation: Forschungszentrum Jülich, ICS-6 Structural Biochemistry, Jülich, Germany; Heinrich-Heine-Universität Düsseldorf, Institut für Physikalische Biologie, Düsseldorf, Germany.
authors.forename: Luitgard
authors.initials: L
authors.lastname: Nagel-Steger
authors.affiliation: Forschungszentrum Jülich, ICS-6 Structural Biochemistry, Jülich, Germany; Heinrich-Heine-Universität Düsseldorf, Institut für Physikalische Biologie, Düsseldorf, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Willbold
mesh_terms: D016229:Amyloid beta-Peptides / Q000737:chemistry / Q000378:metabolism*; D001704:Biopolymers / Q000737:chemistry / Q000378:metabolism; D002850:Chromatography, Gel; D007700:Kinetics; D011487:Protein Conformation; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D016229:Amyloid beta-Peptides; D001704:Biopolymers