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From Proteopedia
THREE-DIMENSIONAL CRYSTAL STRUCTURE OF THE A-TRACT DNA DODECAMER D(CGCAAATTTGCG) COMPLEXED WITH THE MINOR-GROOVE-BINDING DRUG HOECHST 33258
Overview
The molecular structure of the DNA A-tract dodecamer d(CGCAAATTTGCG) complexed with the drug Hoechst 33258 has been determined by X-ray diffraction analysis. The Hoechst molecule binds in the DNA minor groove covering the sequence AATTT of the central A-tract, with the piperazine group close to one of the GC regions. The drug molecule makes two three-centered hydrogen bonds from the nitrogen atoms of the benzimidazole rings to the N3 and O2 atoms of the DNA bases. Although a high propeller twist is observed in the A-tract, only one unsymmetrical three-centered hydrogen bond is present in the DNA major groove. The structure is compared with other minor-groove-binding drug complexes and the influence of these drugs on DNA A-tracts is discussed.
About this Structure
Full crystallographic information is available from OCA.
Reference
Three-dimensional crystal structure of the A-tract DNA dodecamer d(CGCAAATTTGCG) complexed with the minor-groove-binding drug Hoechst 33258., Vega MC, Garcia Saez I, Aymami J, Eritja R, Van der Marel GA, Van Boom JH, Rich A, Coll M, Eur J Biochem. 1994 Jun 15;222(3):721-6. PMID:7517864 Page seeded by OCA on Sat May 3 18:24:36 2008
