Crystal structure of d(GCGAAAGCT) containing a parallel-stranded duplex with homo base pairs and an anti-parallel duplex with Watson-Crick base pairs.

ABSTRACT: A DNA fragment d(GCGAAAGCT), known to adopt a stable mini-hairpin structure in solution, has been crystallized in the space group I4(1)22 with the unit-cell dimensions a = b = 53.4 A and c = 54.0 A, and the crystal structure has been determined at 2.5 A resolution. The four nucleotide residues CGAA of the first half of the oligomer form a parallel duplex with another half through the homo base pairs, C2:C2+ (singly-protonated between the Watson- Crick sites), G3:G3 (between the minor groove sites), A4:A4 (between the major groove sites) and A5:A5 (between the Watson-Crick sites). The two strands remaining in the half of the parallel duplex are split away in different directions, and they pair in an anti-parallel B-form duplex with the second half extending from a neighboring parallel duple

SUBMITTER: Sunami T 

PROVIDER: S-EPMC137954 | biostudies-literature | 2002 Dec

REPOSITORIES: biostudies-literature