title: Conformational dynamics and aggregation behavior of piezoelectric diphenylalanine peptides in an external electric field.
abstract: Aromatic peptides including diphenylalanine (FF) have the capacity to self-assemble into ordered, biocompatible nanostructures with piezoelectric properties relevant to a variety of biomedical applications. Electric fields are commonly applied to align FF nanotubes, yet little is known about the effect of the electric field on the assembly process. Using all-atom molecular dynamics with explicit water molecules, we examine the response of FF monomers to the application of a constant external electric field over a range of intensities. We probe the aggregation mechanism of FF peptides, and find that the presence of even relatively weak fields can accelerate ordered aggregation, primarily by facilitating the alignment of individual molecular dipole moments. This is modulated by the conformational response of individual FF peptides (e.g., backbone stretching) and by the cooperative alignment of neighboring FF and water molecules. These observations may facilitate future studies on the controlled formation of nanostructured aggregates of piezoelectric peptides and the understanding of their electro-mechanical properties.
authors.affiliation: School of Physics, University College Dublin, Belfield, Dublin 4, Ireland; Complex and Adaptive Systems Laboratory, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Kelly
authors.affiliation: School of Physics, University College Dublin, Belfield, Dublin 4, Ireland; Complex and Adaptive Systems Laboratory, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Northey
authors.affiliation: School of Physics, University College Dublin, Belfield, Dublin 4, Ireland; Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Kate
authors.initials: K
authors.lastname: Ryan
authors.affiliation: Laboratory of Computational Biology, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, United States.
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Brooks
authors.affiliation: Department of Materials and Ceramic Engineering & CICECO, University of Aveiro, Portugal.
authors.forename: Andrei L
authors.initials: AL
authors.lastname: Kholkin
authors.affiliation: School of Physics, University College Dublin, Belfield, Dublin 4, Ireland; Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Rodriguez
authors.affiliation: School of Physics, University College Dublin, Belfield, Dublin 4, Ireland; Complex and Adaptive Systems Laboratory, University College Dublin, Belfield, Dublin 4, Ireland. Electronic address: buchete@ucd.ie.
authors.forename: Nicolae-Viorel
authors.initials: NV
authors.lastname: Buchete
mesh_terms: D004151:Dipeptides; D004560:Electricity; D006860:Hydrogen Bonding; D056004:Molecular Dynamics Simulation; D049329:Nanostructures / Q000737:chemistry; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000737:chemistry; D017434:Protein Structure, Tertiary; D012997:Solvents / Q000737:chemistry
chemical_list: D004151:Dipeptides; D012997:Solvents; C026650:phenylalanylphenylalanine; D010649:Phenylalanine
keywords: Atomistic molecular dynamics; Diphenylalanine peptide; External electric field; Peptide aggregate; Peptide–peptide interaction; Piezoelectric peptide