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. (C) 2014 Elsevier B.V. All rights reserved.
keywords
MOLECULAR-DYNAMICS; BUILDING-BLOCKS; LIPID-MEMBRANES; FORCE-FIELDS; NANOTUBES; DIELECTROPHORESIS; FIBRILS; MANIPULATION; SIMULATIONS; POTENTIALS
subject category
Biochemistry & Molecular Biology; Biophysics; Chemistry
authors
Kelly, CM; Northey, T; Ryan, K; Brooks, BR; Kholkin, AL; Rodriguez, BJ; Buchete, NV
our authors
acknowledgements
This work was supported by the University College Dublin Structured Ph.D. Programme in Simulation Science, funded under the Programme for Research in Third Level Institutions (PRTLI) Cycle 5 which is co-funded by the European Regional Development Fund (ERDF), and also by the European Commission within FP7 Marie Curie Initial Training Network