Incorporation of a disaccharide nucleoside into the backbone of double-stranded DNA: crystallization and preliminary X-ray diffraction.

Incorporation of a disaccharide nucleoside into double-stranded DNA can be considered as a chemical (non-enzymatic) alternative for site-specific cleavage of DNA. Crystals of the sequence d(CGCGAATT*CGCG), where * is an incorporated ribose, were obtained by hanging-drop vapour diffusion and diffracted to 2.6 A. The crystals belong to the orthorhombic space group P222(1), with unit-cell parameters a = 41.52, b = 57.63, c = 81.39 A, indicating a new crystal packing motif for an oligonucleotide dodecamer sequence.