Graphene Symmetry Amplified by Designed Peptide Self-Assembly.
We present a strategy for designed self-assembly of peptides into two-dimensional monolayer crystals on the surface of graphene and graphite. As predicted by computation, designed peptides assemble on the surface of graphene to form very long, parallel, in-register β-sheets, which we call β-tapes. Peptides extend perpendicularly to the long axis of each β-tape, defining its width, with hydrogen bonds running along the axis. Tapes align on the surface to create highly regular microdomains containing 4-nm pitch striations. Moreover, in agreement with calculations, the atomic structure of the underlying graphene dictates the arrangement of the β-tapes, as they orient along one of six directions defined by graphene's sixfold symmetry. A cationic-assembled peptide surface is shown here to strongly adhere to DNA, preferentially orienting the double helix along β-tape axes. This orientational preference is well anticipated from calculations, given the underlying peptide layer structure. These studies illustrate how designed peptides can amplify the Ångstrom-level atomic symmetry of a surface onto the micrometer scale, further imparting long-range directional order onto the next level of assembly. The remarkably stable nature of these assemblies under various environmental conditions suggests applications in enzymelike catalysis, biological interfaces for cellular recognition, and two-dimensional platforms for studying DNA-peptide interactions.
Department of Physics, Northeastern University, Boston, Massachusetts.
Gina-Mirela
GM
Mustata
SKKU Advanced Institute of Nanotechnology and Department of Chemistry, Sungkyunkwan University, Seoul, Korea; Center for Neuroscience Imaging Research, Institute for Basic Science(IBS), Suwon, Korea. Electronic address: yhkim94@skku.edu.
Yong Ho
YH
Kim
Department of Computer Science, Dartmouth College, Hanover, New Hampshire.
Jian
J
Zhang
Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco.
William F
WF
DeGrado
Department of Computer Science, Dartmouth College, Hanover, New Hampshire; Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire. Electronic address: gevorg.grigoryan@dartmouth.edu.
Gevorg
G
Grigoryan
Department of Physics, Northeastern University, Boston, Massachusetts. Electronic address: wanunu@neu.edu.
Meni
M
Wanunu
D002412:Cations / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D019286:Endopeptidase K / Q000378:metabolism; D006108:Graphite / Q000737:chemistry*; D007700:Kinetics; D018625:Microscopy, Atomic Force; D056004:Molecular Dynamics Simulation; D010455:Peptides / Q000378:metabolism*; D011485:Protein Binding; D055503:Protein Multimerization; D055550:Protein Stability; D017433:Protein Structure, Secondary; D055672:Static Electricity; D014867:Water / Q000737:chemistry
D002412:Cations; D010455:Peptides; D014867:Water; D006108:Graphite; D004247:DNA; D019286:Endopeptidase K