Nucleic Acids Research, 1987, Vol. 15, No. 16 6589-6605
© 1987
Articles |
Structural features and hydration of a dodecamer duplex containing two C.A mispairs
University Chemical Laboratory Lensfield Road, Cambridge CB2 1EW 1Department of Chemistry, University of Edinburgh West Mains Road, Edinburgh, UK
*To whom correspondence should be addressed
Received May 19, 1987. Revised July 8, 1987. Accepted July 8, 1987.
X-ray diffraction techniques have been used to characterise the crystal and molecular structure of the deoxyoligomer d(C-G-C-A-A-A-T-T-C-G-C-G) at 2.5Å resolution. The final R factor is 0.19 with the location of 78 solvent molecules. The oligomer crystallises in a B-DNA type conformation with two strands coiled about each other to produce a duplex. This double helix consists of four A.T and six G.C Watson-Crick base pairs and two C.A mispairs. The mismatched base pairs adopt a "wobble" type structure with the cytosine displaced laterally into the major groove, the adenine into the minor groove. We have proposed that the two close contacts observed in the C.A pairing represent two hydrogen bonds one of which results from protonation of adenine. The mispairs are accommodated in the double helix with small adjustments in the conformation of the sugar-phosphate backbone* Details of the backbone conformation, base stacking interactions, thermal parameters and the hydration are now presented and compared with those of the native oligomer d(C-G-C-G-A-A-T-T-C-G-C-G) and with variations of this sequence containing G.T and G.A mispairs.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
V. C. Pierre, J. T. Kaiser, and J. K. Barton Insights into finding a mismatch through the structure of a mispaired DNA bound by a rhodium intercalator PNAS, January 9, 2007; 104(2): 429 - 434. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. R. Salsbury Jr, J. E. Clodfelter, M. B. Gentry, T. Hollis, and K. D. Scarpinato The molecular mechanism of DNA damage recognition by MutS homologs and its consequences for cell death response. Nucleic Acids Res., January 1, 2006; 34(8): 2173 - 2185. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Natrajan, M. H. Lamers, J. H. Enzlin, H. H. K. Winterwerp, A. Perrakis, and T. K. Sixma Structures of Escherichia coli DNA mismatch repair enzyme MutS in complex with different mismatches: a common recognition mode for diverse substrates Nucleic Acids Res., August 15, 2003; 31(16): 4814 - 4821. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. K. Bhattacharya, J. Cha, and J. K. Barton 1H NMR determination of base-pair lifetimes in oligonucleotides containing single base mismatches Nucleic Acids Res., November 1, 2002; 30(21): 4740 - 4750. [Abstract] [Full Text] [PDF] |
||||

