Nucleic acid duplexes incorporating a dissociable covalent base pair

Gao, K.; Orgel, L. E.; Bada, J. L.

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NASA NTRS · 20040141727

Nucleic acid duplexes incorporating a dissociable covalent base pair

Gao, K.·Orgel, L. E.·Bada, J. L.

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Abstract

We have used molecular modeling techniques to design a dissociable covalently bonded base pair that can replace a Watson-Crick base pair in a nucleic acid with minimal distortion of the structure of the double helix. We introduced this base pair into a potential precursor of a nucleic acid double helix by chemical synthesis and have demonstrated efficient nonenzymatic template-directed ligation of the free hydroxyl groups of the base pair with appropriate short oligonucleotides. The nonenzymatic ligation reactions, which are characteristic of base paired nucleic acid structures, are abolished when the covalent base pair is reduced and becomes noncoplanar. This suggests that the covalent base pair linking the two strands in the duplex is compatible with a minimally distorted nucleic acid double-helical structure.

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Non-NASA Center NASA Discipline Exobiology Base Pairing Nucleic Acid Conformation Nucleic Acids/chemistry DNA/chemistry Oligodeoxyribonucleotides/chemistry Models, Molecular Computer Simulation Cytidine/analogs & derivatives/chemistry Nucleosides/chemistry Support, U.S. Gov't, Non-P.H.S

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Gao, K., Orgel, L. E., Bada, J. L.. 1999-12-21. Nucleic acid duplexes incorporating a dissociable covalent base pair. https://ntrs.nasa.gov/citations/20040141727

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