1D27

HIGH-RESOLUTION STRUCTURE OF A MUTAGENIC LESION IN DNA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Observed: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

High-resolution structure of a mutagenic lesion in DNA.

Leonard, G.A.Thomson, J.Watson, W.P.Brown, T.

(1990) Proc Natl Acad Sci U S A 87: 9573-9576

  • DOI: 10.1073/pnas.87.24.9573
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The self-complementary dodecanucleotide d[CGC(m6G)AATTTGCG]2 (where m6G is O6-methylguanine), which contains two m6G.T base pairs, has been analyzed by x-ray diffraction methods and the structure has been refined to a residual error of R = 0.185 at 2 ...

    The self-complementary dodecanucleotide d[CGC(m6G)AATTTGCG]2 (where m6G is O6-methylguanine), which contains two m6G.T base pairs, has been analyzed by x-ray diffraction methods and the structure has been refined to a residual error of R = 0.185 at 2.0-A resolution. The m6G.T mispair closely resembles a Watson-Crick base pair and there are very few structural differences between the m6G.T duplex and the native analogue. The similarity between the m6G.T base pair and a normal G.C base pair explains the failure of mismatch repair enzymes to recognize and remove this mutagenic lesion. A series of ultraviolet melting studies over a wide pH range on a related dodecamer indicate that the m6G.C mispair can exist in two conformations; one is a wobble pair and the other is a protonated Watson-Crick pair. The former, which predominates at physiological pH, will be removed by normal proofreading and repair enzymes, whereas the latter is likely to escape detection. Hence, the occasional occurrence of the protonated m6G.C base pair may explain why the presence of m6G in genomic DNA does not always give rise to a mutation.


    Organizational Affiliation

    Department of Chemistry, Edinburgh University, Scotland, United Kingdom.



Macromolecules
  • Find similar nucleic acids by: Sequence   |   Structure
Entity ID: 1
MoleculeChainsLengthOrganism
DNA (5'-D(*CP*GP*CP*(6OG)P*AP*AP*TP*TP*TP*GP*CP*G)-3')A, B12N/A
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Observed: 0.185 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 25.44α = 90
b = 40.7β = 90
c = 65.99γ = 90
Software Package:
Software NamePurpose
NUCLSQrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1992-04-07
    Type: Initial release
  • Version 1.1: 2008-05-22
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance