Pseudohexagonal 2D DNA crystals from double crossover cohesion

Abstract

Two-dimensional pseudohexagonal trigonal arrays have been constructed by self-assembly from DNA. The motif used is a bulged-junction DNA triangle whose edges and extensions are DNA double crossover (DX) molecules, rather than conventional DNA double helices. Experiments were performed to establish whether the success of this system results from the added stiffness of DX molecules or the presence of two sticky ends at the terminus of each edge. Removal of one sticky end precludes lattice formation, suggesting that it is the double sticky end that is the primary factor enabling lattice formation.