178D

CRYSTAL STRUCTURE OF A DNA DUPLEX CONTAINING 8-HYDROXYDEOXYGUANINE.ADENINE BASE-PAIRS

Summary for 178D

• Entry DOI: 10.2210/pdb178d/pdb
• Descriptor: DNA (5'-D(*CP*GP*CP*AP*AP*AP*TP*TP*(8OG)P*GP*CP*G)-3') (2 entities in total)
• Functional Keywords: b-dna, double helix, modified, mismatched, dna
• Total number of polymer chains: 2
• Total formula weight: 7406.83

Authors

McAuley-Hecht, K.E.,Leonard, G.A.,Gibson, N.J.,Thomson, J.B.,Watson, W.P.,Hunter, W.N.,Brown, T. (deposition date: 1994-05-19, release date: 1994-10-04, Last modification date: 2024-02-07)

Primary citation

McAuley-Hecht, K.E.,Leonard, G.A.,Gibson, N.J.,Thomson, J.B.,Watson, W.P.,Hunter, W.N.,Brown, T.
Crystal structure of a DNA duplex containing 8-hydroxydeoxyguanine-adenine base pairs.
Biochemistry, 33:10266-10270, 1994

PubMed Abstract: The crystal structure of the oligonucleotide d(CGCAAATTO8GGCG), containing the chemically modified base 8-hydroxydeoxyguanine (O8G), has been determined at 2.5-A resolution and refined to a crystallographic R-factor of 16.8%. The B-type DNA helix contains standard Watson-Crick base pairs except at the mismatch sites, where O8G adopts a syn conformation and forms hydrogen bonds to adenine in the anti conformation. The thermodynamic stability of the duplex was found by UV melting techniques to be intermediate between the native oligonucleotide d(CGCAAATTTGCG) and an oligonucleotide containing A.G mispairs d(CGCAAATTGGCG). Comparison of the structure of the O8G(syn).A(anti) base pair with those of Watson-Crick base pairs has given a reason why O8G.A base pairs are not well repaired by DNA proofreading enzymes.

PubMed: 8068665
DOI: 10.1021/bi00200a006

Experimental method

X-RAY DIFFRACTION (2.5 Å)