PMID: 21969542

Authors:

Hall JP, O'Sullivan K, Naseer A, Smith JA, Kelly JM, Cardin CJ

Title:

Structure determination of an intercalating ruthenium dipyridophenazine complex which kinks DNA by semiintercalation of a tetraazaphenanthrene ligand.

Journal:

Proc Natl Acad Sci U S A. 2011 Oct 3.

Abstract:

We describe a crystal structure, at atomic resolution (1.1 A, 100 K), of a ruthenium polypyridyl complex bound to duplex DNA, in which one ligand acts as a wedge in the minor groove, resulting in the 51 degrees kinking of the double helix. The complex cation Lambda-[Ru(1,4,5,8-tetraazaphenanthrene)(2)(dipyridophenazine)](2+) crystallizes in a 11 ratio with the oligonucleotide d(TCGGCGCCGA) in the presence of barium ions. Each complex binds to one duplex by intercalation of the dipyridophenazine ligand and also by semiintercalation of one of the orthogonal tetraazaphenanthrene ligands into a second symmetrically equivalent duplex. The result is noncovalent cross-linking and marked kinking of DNA.