Tuning the Cavity Size and Chirality of Self-Assembling 3D DNA Crystals

J Am Chem Soc. 2017 Aug 16;139(32):11254-11260. doi: 10.1021/jacs.7b06485. Epub 2017 Aug 2.

Abstract

The foundational goal of structural DNA nanotechnology-the field that uses oligonucleotides as a molecular building block for the programmable self-assembly of nanostructured systems-was to use DNA to construct three-dimensional (3D) lattices for solving macromolecular structures. The programmable nature of DNA makes it an ideal system for rationally constructing self-assembled crystals and immobilizing guest molecules in a repeating 3D array through their specific stereospatial interactions with the scaffold. In this work, we have extended a previously described motif (4 × 5) by expanding the structure to a system that links four double-helical layers; we use a central weaving oligonucleotide containing a sequence of four six-base repeats (4 × 6), forming a matrix of layers that are organized and dictated by a series of Holliday junctions. In addition, we have assembled mirror image crystals (l-DNA) with the identical sequence that are completely resistant to nucleases. Bromine and selenium derivatives were obtained for the l- and d-DNA forms, respectively, allowing phase determination for both forms and solution of the resulting structures to 3.0 and 3.05 Å resolution. Both right- and left-handed forms crystallized in the trigonal space groups with mirror image 3-fold helical screw axes P32 and P31 for each motif, respectively. The structures reveal a highly organized array of discrete and well-defined cavities that are suitable for hosting guest molecules and allow us to dictate a priori the assembly of guest-DNA conjugates with a specified crystalline hand.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bromine / chemistry
  • Crystallization
  • Crystallography, X-Ray
  • DNA / chemistry*
  • Models, Molecular
  • Nanostructures / chemistry
  • Nanotechnology
  • Nucleic Acid Conformation
  • Oligonucleotides / chemistry
  • Selenium / chemistry
  • Stereoisomerism

Substances

  • Oligonucleotides
  • DNA
  • Selenium
  • Bromine