Elementary smectic ordering of “gapped” DNA duplexes

ORAL

Abstract

We used small angle X-ray scattering and optical microscopy to study the liquid crystalline behavior of “gapped” DNA duplexes in aqueous solution. Our previous work1 revealed the occurrence of a smectic-A phase for DNA concentrations in the range ~230 to ~300 mg/ml and for a single-strand “gap” between duplexes of 20 thymine bases. Here we describe evidence for two coexisting/competing smectic-A-like layer structures, whose relative population varies with temperature and “gap” length. Smectic layering occurs for gap lengths down to 4 bases but disappears when the gap is reduced to 2 bases. Transitions from smectic to cholesteric/nematic state are observed as a function of temperature.

Reference
(1) Salamonczyk, M.; Zhang, J.; Portale, G.; Zhu, C.; Kentzinger, E.; Gleeson, J. T.; Jakli, A.; De Michele, C.; Dhont, J. K. G.; Sprunt, S.; et al. Smectic Phase in Suspensions of Gapped DNA Duplexes. Nat. Commun. 2016, 7, 13358.

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Presenters

  • Prabesh Gyawali

    Department of Physics, Kent State University, Kent, OH USA

Authors

  • Prabesh Gyawali

    Department of Physics, Kent State University, Kent, OH USA

  • Rony Saha

    Department of Physics, Kent State University, Kent, OH USA, Kent State University

  • Mirek Salamonczyk

    Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA USA,

  • James Gleeson

    Department of Physics, Kent State University, Kent, OH USA, Department of Physics, Kent State University, Kent State University

  • Antal Istvan Jakli

    Liquid Crystal Institute, Kent State University, Department of Physics and Advanced Materials Liquid Crystal Institute, Kent State University, Chemical Physics Interdisciplinary Program, Liquid Crystal Institute, Kent State University, Kent, OH USA, Chemical Physics Interdisciplinary Program, Kent State University, Advanced Materials & Liquid Crystal Institute, Kent State University, Kent State University, Department of Physics, Kent State University,Kent, OH 44240, USA

  • Hamza Balci

    Kent State University, Department of Physics, Kent State University, Kent, OH USA

  • Samuel Sprunt

    Department of Physics, Kent State University, Kent, OH USA, Kent State University