title: Structural and Mechanical Properties of Amyloid Beta Fibrils: A Combined Experimental and Theoretical Approach.
abstract: In this combined experimental (deep ultraviolet resonance Raman (DUVRR) spectroscopy and atomic force microscopy (AFM)) and theoretical (molecular dynamics (MD) simulations and stress-strain (SS)) study, the structural and mechanical properties of amyloid beta (Aβ40) fibrils have been investigated. The DUVRR spectroscopy and AFM experiments confirmed the formation of linear, unbranched and β-sheet rich fibrils. The fibrils (Aβ40)n, formed using n monomers, were equilibrated using all-atom MD simulations. The structural properties such as β-sheet character, twist, interstrand distance, and periodicity of these fibrils were found to be in agreement with experimental measurements. Furthermore, Young's modulus (Y) = 4.2 GPa computed using SS calculations was supported by measured values of 1.79 ± 0.41 and 3.2 ± 0.8 GPa provided by two separate AFM experiments. These results revealed size dependence of structural and material properties of amyloid fibrils and show the utility of such combined experimental and theoretical studies in the design of precisely engineered biomaterials.
authors.affiliation: Department of Chemistry, University of Miami , Coral Gables, Florida 33146, United States.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Paul
authors.affiliation: Department of Chemistry, University of Miami , Coral Gables, Florida 33146, United States.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Hoffmann
authors.affiliation: Department of Chemical and Life Science Engineering, Virginia Commonwealth University , Richmond, Virginia 23284, United States.
authors.forename: Congzhou
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Chemistry, University at Albany, State University of New York , Albany, New York 12222, United States.
authors.forename: Maruda
authors.initials: M
authors.lastname: Shanmugasundaram
authors.affiliation: Dassault Systèmes BIOVIA , San Deigo, California 92121, United States.
authors.forename: Jason
authors.initials: J
authors.lastname: DeJoannis
authors.affiliation: Department of Chemistry, University at Albany, State University of New York , Albany, New York 12222, United States.
authors.forename: Alexander
authors.initials: A
authors.lastname: Shekhtman
authors.affiliation: Department of Chemistry, University at Albany, State University of New York , Albany, New York 12222, United States.
authors.forename: Igor K
authors.initials: IK
authors.lastname: Lednev
authors.affiliation: Department of Chemical and Life Science Engineering, Virginia Commonwealth University , Richmond, Virginia 23284, United States.
authors.forename: Vamsi K
authors.initials: VK
authors.lastname: Yadavalli
authors.affiliation: Department of Chemistry, University of Miami , Coral Gables, Florida 33146, United States.
authors.forename: Rajeev
authors.initials: R
authors.lastname: Prabhakar