1DA1

STRUCTURAL CHARACTERISATION OF THE BROMOURACIL-GUANINE BASE PAIR MISMATCH IN A Z-DNA FRAGMENT

Summary for 1DA1

• Entry DOI: 10.2210/pdb1da1/pdb
• Descriptor: DNA (5'-D(*(BRU)P*GP*CP*GP*CP*G)-3'), MAGNESIUM ION (3 entities in total)
• Functional Keywords: z-dna, double helix, modified, mismatched, dna
• Total number of polymer chains: 2
• Total formula weight: 3804.48

Authors

Brown, T.,Kneale, G.,Hunter, W.N.,Kennard, O. (deposition date: 1992-10-17, release date: 1993-07-15, Last modification date: 2024-02-07)

Primary citation

Brown, T.,Kneale, G.,Hunter, W.N.,Kennard, O.
Structural characterisation of the bromouracil.guanine base pair mismatch in a Z-DNA fragment.
Nucleic Acids Res., 14:1801-1809, 1986

PubMed Abstract: The deoxyoligonucleotide d(BrU-G-C-G-C-G) was crystallised at pH 8.2 and its structure analysed by X-ray diffraction. The unit cell, of dimensions a = 17.94, b = 30.85, c = 49.94A contains four DNA duplexes in space group P2(1)2(1)2(1). The duplexes are in the Z conformation, with four Watson-Crick G.C base pairs and two BrU.G base pairs. The structure was refined to an R factor of 0.16 at a resolution of 2.2A with 64 solvent molecules located. The BrU.G base pair mismatch is of the wobble type, with both bases in the major tautomer form and hydrogen bonds linking 0-2 of BrU with N-1 of G and N3 of BrU with 0-6 of G. There is no indication of the presence of ionised base pairs, in spite of the high pH of crystallisation. The results are discussed in terms of the mutagenic properties of 5- bromouracil.

PubMed: 3951996
DOI: 10.1093/nar/14.4.1801

Experimental method

X-RAY DIFFRACTION (2.25 Å)