1VAQ:
reference: Crystal structure of the [Mg2+-(chromomycin A3)2]-d(TTGGCCAA)2 complex reveals GGCC binding specificity of the drug dimer chelated by a metal ion., Hou MH, Robinson H, Gao YG, Wang AH, Nucleic Acids Res 2004 Apr 23;32(7):2214-22. Print 2004. PMID: 15107489

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