114d
From Proteopedia
(New page: 200px<br /><applet load="114d" size="450" color="white" frame="true" align="right" spinBox="true" caption="114d, resolution 2.500Å" /> '''INOSINE-ADENINE BAS...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:114d.gif|left|200px]]<br /><applet load="114d" size=" | + | [[Image:114d.gif|left|200px]]<br /><applet load="114d" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="114d, resolution 2.500Å" /> | caption="114d, resolution 2.500Å" /> | ||
'''INOSINE-ADENINE BASE PAIRS IN A B-DNA DUPLEX'''<br /> | '''INOSINE-ADENINE BASE PAIRS IN A B-DNA DUPLEX'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The structure of the synthetic deoxydodecamer d(C-G-C-I-A-A-T-T-A-G-C-G) | + | The structure of the synthetic deoxydodecamer d(C-G-C-I-A-A-T-T-A-G-C-G) has been determined by single crystal X-ray diffraction techniques at 2.5A resolution. The refinement converged with a crystallographic residual, R = 0.19 and the location of 64 solvent molecules. The sequence crystallises as a B-DNA helix with 10 Watson-Crick base-pairs (4 A.T. and 6 G.C) and 2 inosine.adenine (I.A) pairs. The present work shows that in the purine.purine base-pairs the adenine adopts syn orientation with respect to the furanose moiety while the inosine is in the trans (anti) orientation. Two hydrogen bonds link the I.A. base-pair, one between N-1(I) and N-7(A), the other between O-6(I) and N-6(A). This bulky purine.purine base-pair is incorporated in the double helix at two positions with little distortion of either local or global conformation. The pairing observed in this study is presented as a model for I.A base-pairs in RNA codon-anticodon interactions and may help explain the thermodynamic stability of inosine containing base-pairs. Conformational parameters and base stacking interactions are presented and where appropriate compared with those of the native compound, d(C-G-C-G-A-A-T-T-C-G-C-G) and with other studies of oligonucleotides containing purine.purine base-pairs. |
==About this Structure== | ==About this Structure== | ||
| - | 114D is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http:// | + | 114D is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=114D OCA]. |
==Reference== | ==Reference== | ||
| Line 13: | Line 13: | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Brown, T.]] | [[Category: Brown, T.]] | ||
| - | [[Category: Corfield, P | + | [[Category: Corfield, P W.R.]] |
| - | [[Category: Hunter, W | + | [[Category: Hunter, W N.]] |
[[Category: Kennard, O.]] | [[Category: Kennard, O.]] | ||
[[Category: Robinson, P.]] | [[Category: Robinson, P.]] | ||
| Line 22: | Line 22: | ||
[[Category: modified]] | [[Category: modified]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:37:36 2008'' |
Revision as of 09:37, 21 February 2008
|
INOSINE-ADENINE BASE PAIRS IN A B-DNA DUPLEX
Overview
The structure of the synthetic deoxydodecamer d(C-G-C-I-A-A-T-T-A-G-C-G) has been determined by single crystal X-ray diffraction techniques at 2.5A resolution. The refinement converged with a crystallographic residual, R = 0.19 and the location of 64 solvent molecules. The sequence crystallises as a B-DNA helix with 10 Watson-Crick base-pairs (4 A.T. and 6 G.C) and 2 inosine.adenine (I.A) pairs. The present work shows that in the purine.purine base-pairs the adenine adopts syn orientation with respect to the furanose moiety while the inosine is in the trans (anti) orientation. Two hydrogen bonds link the I.A. base-pair, one between N-1(I) and N-7(A), the other between O-6(I) and N-6(A). This bulky purine.purine base-pair is incorporated in the double helix at two positions with little distortion of either local or global conformation. The pairing observed in this study is presented as a model for I.A base-pairs in RNA codon-anticodon interactions and may help explain the thermodynamic stability of inosine containing base-pairs. Conformational parameters and base stacking interactions are presented and where appropriate compared with those of the native compound, d(C-G-C-G-A-A-T-T-C-G-C-G) and with other studies of oligonucleotides containing purine.purine base-pairs.
About this Structure
114D is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Inosine.adenine base pairs in a B-DNA duplex., Corfield PW, Hunter WN, Brown T, Robinson P, Kennard O, Nucleic Acids Res. 1987 Oct 12;15(19):7935-49. PMID:3671069
Page seeded by OCA on Thu Feb 21 11:37:36 2008
