428D:
reference: Structure of the potassium form of CGCGAATTCGCG: DNA deformation by electrostatic collapse around inorganic cations., Shui X, Sines CC, McFail-Isom L, VanDerveer D, Williams LD, Biochemistry 1998 Dec 1;37(48):16877-87. PMID: 9836580

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