Solution structure of the mithramycin dimer-DNA complex

Techniques involving NMR-molecular dynamics and relaxation matrix refinement were utilised in the structure analysis of complexes produced from Mg2+-coordinated mithramycin dimer binding to self-complementary d(T-G-G-C-C-A) and d(T-C-G-C-G-A) duplexes. The molecular structure of the mithramycin dimer d(T-C-G-C-G-A) reveals a two-fold center of symmetry. The aglycon C-8 hydroxyl oxygens are hydrogen bonded to guanine amino protons in the complex due to the positioning of divalent cation coordinated glycons, opposite the central (G3-C4). (G3-C4) segment.