1H NMR studies on the interaction between distamycin A and a symmetrical DNA dodecamer.

摘要: High-resolution NMR techniques have been used to examine the structural and dynamical features of interaction between distamycin A self-complementary DNA dodecamer duplex d-(CGCGAATTCGCG)2. The proton resonances d(CGCGAATTCGCG)2 completely assigned by previous two-dimensional studies [Hare, D. R., Wemmer, E., Chou, S. H., Drobny, G., & Reid, B. R. (1983) J. Mol. Biol. 171, 319-336]. Addition asymmetric drug molecule symmetric leads formation an complex as evidenced a doubling over much spectrum. In exchange experiments, strong cross-peaks were observed uncomplexed drug-bound resonances, permitting direct assignment many from previously free resonances. Weaker formerly symmetry related indicate that flips head-to-tail on one with half frequency at which it leaves completely. experiments performed in H2O, nuclear Overhauser effects (NOEs) each amide adenine C2H pyrrole H3 ring proton. D2O solutions, intermolecular NOEs three resonance, weaker C1'H combined NOE data allow us position unambiguously dodecamer, spanning central AATT segment minor groove.