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2alz
From Proteopedia
(New page: 200px<br /> <applet load="2alz" size="450" color="white" frame="true" align="right" spinBox="true" caption="2alz, resolution 2.50Å" /> '''Ternary Complex of ...) |
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| - | [[Image:2alz.gif|left|200px]]<br /> | + | [[Image:2alz.gif|left|200px]]<br /><applet load="2alz" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="2alz" size=" | + | |
caption="2alz, resolution 2.50Å" /> | caption="2alz, resolution 2.50Å" /> | ||
'''Ternary Complex of hPoli with DNA and dCTP'''<br /> | '''Ternary Complex of hPoli with DNA and dCTP'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Human DNA polymerase iota (hPoliota), a member of the Y family of DNA | + | Human DNA polymerase iota (hPoliota), a member of the Y family of DNA polymerases, differs in remarkable ways from other DNA polymerases, incorporating correct nucleotides opposite template purines with a much higher efficiency and fidelity than opposite template pyrimidines. We present here the crystal structure of hPoliota bound to template G and incoming dCTP, which reveals a G.C + Hoogsteen base pair in a DNA polymerase active site. We show that the hPoliota active site has evolved to favor Hoogsteen base pairing, wherein the template sugar is fixed in a cavity that reduces the C1'-C1' distance across the nascent base pair from approximately 10.5 A in other DNA polymerases to 8.6 A in hPoliota. The rotation of G from anti to syn is then largely in response to this curtailed C1'-C1' distance. A G.C+ Hoogsteen base pair suggests a specific mechanism for hPoliota's ability to bypass N(2)-adducted guanines that obstruct replication. |
==About this Structure== | ==About this Structure== | ||
| - | 2ALZ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with MG and DCP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] Full crystallographic information is available from [http:// | + | 2ALZ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=DCP:'>DCP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ALZ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Aggarwal, A | + | [[Category: Aggarwal, A K.]] |
| - | [[Category: Johnson, R | + | [[Category: Johnson, R E.]] |
| - | [[Category: Nair, D | + | [[Category: Nair, D T.]] |
[[Category: Prakash, L.]] | [[Category: Prakash, L.]] | ||
[[Category: Prakash, S.]] | [[Category: Prakash, S.]] | ||
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[[Category: ternary complex]] | [[Category: ternary complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:28:49 2008'' |
Revision as of 14:28, 21 February 2008
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Ternary Complex of hPoli with DNA and dCTP
Overview
Human DNA polymerase iota (hPoliota), a member of the Y family of DNA polymerases, differs in remarkable ways from other DNA polymerases, incorporating correct nucleotides opposite template purines with a much higher efficiency and fidelity than opposite template pyrimidines. We present here the crystal structure of hPoliota bound to template G and incoming dCTP, which reveals a G.C + Hoogsteen base pair in a DNA polymerase active site. We show that the hPoliota active site has evolved to favor Hoogsteen base pairing, wherein the template sugar is fixed in a cavity that reduces the C1'-C1' distance across the nascent base pair from approximately 10.5 A in other DNA polymerases to 8.6 A in hPoliota. The rotation of G from anti to syn is then largely in response to this curtailed C1'-C1' distance. A G.C+ Hoogsteen base pair suggests a specific mechanism for hPoliota's ability to bypass N(2)-adducted guanines that obstruct replication.
About this Structure
2ALZ is a Single protein structure of sequence from Homo sapiens with and as ligands. Active as DNA-directed DNA polymerase, with EC number 2.7.7.7 Full crystallographic information is available from OCA.
Reference
Human DNA polymerase iota incorporates dCTP opposite template G via a G.C + Hoogsteen base pair., Nair DT, Johnson RE, Prakash L, Prakash S, Aggarwal AK, Structure. 2005 Oct;13(10):1569-77. PMID:16216587
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