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Backbone-free duplex-stacked monomer nucleic acids exhibiting Watson-Crick selectivity.

ABSTRACT: We demonstrate that nucleic acid (NA) mononucleotide triphosphates (dNTPs and rNTPs), at sufficiently high concentration and low temperature in aqueous solution, can exhibit a phase transition in which chromonic columnar liquid crystal ordering spontaneously appears. Remarkably, this polymer-free state exhibits, in a self-assembly of NA monomers, the key structural elements of biological nucleic acids, including: long-ranged duplex stacking of base pairs, complementarity-dependent partitioning of molecules, and Watson-Crick selectivity, such that, among all solutions of adenosine, cytosine, guanine, and thymine NTPs and their binary mixtures, duplex columnar ordering is most stable in the A-T and C-G combinations.

SUBMITTER: Smith GP

PROVIDER: S-EPMC6099888 | biostudies-other | 2018 Aug

REPOSITORIES: biostudies-other

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Backbone-free duplex-stacked monomer nucleic acids exhibiting Watson-Crick selectivity.

Smith Gregory P GP Fraccia Tommaso P TP Todisco Marco M Zanchetta Giuliano G Zhu Chenhui C Hayden Emily E Bellini Tommaso T Clark Noel A NA

Proceedings of the National Academy of Sciences of the United States of America 20180702 33

We demonstrate that nucleic acid (NA) mononucleotide triphosphates (dNTPs and rNTPs), at sufficiently high concentration and low temperature in aqueous solution, can exhibit a phase transition in which chromonic columnar liquid crystal ordering spontaneously appears. Remarkably, this polymer-free state exhibits, in a self-assembly of NA monomers, the key structural elements of biological nucleic acids, including: long-ranged duplex stacking of base pairs, complementarity-dependent partitioning o ...[more]

PMID: 29967169

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