100D:
reference: Crystal structure of the highly distorted chimeric decamer r(C)d(CGGCGCCG)r(G).spermine complex--spermine binding to phosphate only and minor groove tertiary base-pairing., Ban C, Ramakrishnan B, Sundaralingam M, Nucleic Acids Res 1994 Dec 11;22(24):5466-76. PMID: 7816639

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