197D:
reference: Orthorhombic crystal structure of the A-DNA octamer d(GTACGTAC). Comparison with the tetragonal structure., Langlois d'Estaintot B, Dautant A, Courseille C, Precigoux G, Eur J Biochem 1993 Apr 15;213(2):673-82. PMID: 8477741

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