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1p0u
From Proteopedia
(New page: 200px<br /><applet load="1p0u" size="450" color="white" frame="true" align="right" spinBox="true" caption="1p0u" /> '''Sheared G/C Base Pair'''<br /> ==Overview==...) |
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| - | [[Image:1p0u.gif|left|200px]]<br /><applet load="1p0u" size=" | + | [[Image:1p0u.gif|left|200px]]<br /><applet load="1p0u" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1p0u" /> | caption="1p0u" /> | ||
'''Sheared G/C Base Pair'''<br /> | '''Sheared G/C Base Pair'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Stable DNA loop structures closed by a novel G.C base-pair have been | + | Stable DNA loop structures closed by a novel G.C base-pair have been determined for the single-residue d(GXC) loops (X=A, T, G or C) in low-salt solution by high-resolution nuclear magnetic resonance (NMR) techniques. The closing G.C base-pair in these loops is not of the canonical Watson-Crick type, but adopts instead a unique sheared-type (trans Watson-Crick/sugar-edge) pairing, like those occurring in the sheared mismatched G.A or A.C base-pair, to draw the two opposite strands together. The cytidine residue in the closing base-pair is transformed into the rare syn domain to form two H-bonds with the guanine base and to prevent the steric clash between the G 2NH(2) and the C H-5 protons. Besides, the sugar pucker of the syn cytidine is still located in the regular C2'-endo domain, unlike the C3'-endo domain adopted for the pyrimidines of the out-of-alternation left-handed Z-DNA structure. The facile formation of the compact d(GXC) loops closed by a unique sheared-type G(anti).C(syn) base-pair demonstrates the great potential of the single-stranded d(GXC) triplet repeats to fold into stable hairpins. |
==About this Structure== | ==About this Structure== | ||
| - | 1P0U 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:// | + | 1P0U 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=1P0U OCA]. |
==Reference== | ==Reference== | ||
Sheared-type G(anti).C(syn) base-pair: a unique d(GXC) loop closure motif., Chin KH, Chou SH, J Mol Biol. 2003 May 30;329(2):351-61. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=12758081 12758081] | Sheared-type G(anti).C(syn) base-pair: a unique d(GXC) loop closure motif., Chin KH, Chou SH, J Mol Biol. 2003 May 30;329(2):351-61. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=12758081 12758081] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Chin, K | + | [[Category: Chin, K H.]] |
| - | [[Category: Chou, S | + | [[Category: Chou, S H.]] |
[[Category: nmr]] | [[Category: nmr]] | ||
[[Category: sheared gc base pair]] | [[Category: sheared gc base pair]] | ||
| Line 19: | Line 19: | ||
[[Category: syn cytidine]] | [[Category: syn cytidine]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:23:48 2008'' |
Revision as of 12:23, 21 February 2008
|
Sheared G/C Base Pair
Overview
Stable DNA loop structures closed by a novel G.C base-pair have been determined for the single-residue d(GXC) loops (X=A, T, G or C) in low-salt solution by high-resolution nuclear magnetic resonance (NMR) techniques. The closing G.C base-pair in these loops is not of the canonical Watson-Crick type, but adopts instead a unique sheared-type (trans Watson-Crick/sugar-edge) pairing, like those occurring in the sheared mismatched G.A or A.C base-pair, to draw the two opposite strands together. The cytidine residue in the closing base-pair is transformed into the rare syn domain to form two H-bonds with the guanine base and to prevent the steric clash between the G 2NH(2) and the C H-5 protons. Besides, the sugar pucker of the syn cytidine is still located in the regular C2'-endo domain, unlike the C3'-endo domain adopted for the pyrimidines of the out-of-alternation left-handed Z-DNA structure. The facile formation of the compact d(GXC) loops closed by a unique sheared-type G(anti).C(syn) base-pair demonstrates the great potential of the single-stranded d(GXC) triplet repeats to fold into stable hairpins.
About this Structure
1P0U is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Sheared-type G(anti).C(syn) base-pair: a unique d(GXC) loop closure motif., Chin KH, Chou SH, J Mol Biol. 2003 May 30;329(2):351-61. PMID:12758081
Page seeded by OCA on Thu Feb 21 14:23:48 2008
