Crystal structure of a four-stranded intercalated DNA: d(C4)

Chen, L.; Cai, L.; Zhang, X.; Rich, A.

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NASA NTRS · 20050000288

Crystal structure of a four-stranded intercalated DNA: d(C4)

Chen, L.·Cai, L.·Zhang, X.·Rich, A.

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Abstract

The crystal structure of d(C4) solved at 2.3-A resolution reveals a four-stranded molecule composed of two interdigitated or intercalated duplexes. The duplexes are held together by hemiprotonated cytosine-cytosine base pairs and are parallel stranded, but the two duplexes point in opposite directions. The molecule has a slow right-handed twist of 12.4 degrees between covalently linked cytosine base pairs, and the base stacking distance is 3.1 A. This is in general agreement with the NMR studies. A biological role for DNA in this conformation is suggested.

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Non-NASA Center NASA Discipline Exobiology DNA/chemistry Nucleic Acid Conformation Support, U.S. Gov't, P.H.S Support, Non-U.S. Gov't Crystallography, X-Ray Support, U.S. Gov't, Non-P.H.S Computer Graphics

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Chen, L., Cai, L., Zhang, X., Rich, A.. 1994-11-22. Crystal structure of a four-stranded intercalated DNA: d(C4). https://ntrs.nasa.gov/citations/20050000288

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