2oxm
From Proteopedia
(New page: 200px<br /> <applet load="2oxm" size="450" color="white" frame="true" align="right" spinBox="true" caption="2oxm, resolution 2.5Å" /> '''Crystal structure of...) |
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| - | [[Image:2oxm.gif|left|200px]]<br /> | + | [[Image:2oxm.gif|left|200px]]<br /><applet load="2oxm" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="2oxm" size=" | + | |
caption="2oxm, resolution 2.5Å" /> | caption="2oxm, resolution 2.5Å" /> | ||
'''Crystal structure of a UNG2/modified DNA complex that represent a stabilized short-lived extrahelical state in ezymatic DNA base flipping'''<br /> | '''Crystal structure of a UNG2/modified DNA complex that represent a stabilized short-lived extrahelical state in ezymatic DNA base flipping'''<br /> | ||
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==Overview== | ==Overview== | ||
The enzyme uracil DNA glycosylase (UNG) excises unwanted uracil bases in, the genome using an extrahelical base recognition mechanism. Efficient, removal of uracil is essential for prevention of C-to-T transition, mutations arising from cytosine deamination, cytotoxic U*A pairs arising, from incorporation of dUTP in DNA, and for increasing immunoglobulin gene, diversity during the acquired immune response. A central event in all of, these UNG-mediated processes is the singling out of rare U*A or U*G base, pairs in a background of approximately 10(9) T*A or C*G base pairs in the, human genome. Here we establish for the human and Escherichia coli enzymes, that discrimination of thymine and uracil is initiated by thermally, induced opening of T*A and U*A base pairs and not by active participation, of the enzyme. Thus, base-pair dynamics has a critical role in the, genome-wide search for uracil, and may be involved in initial damage, recognition by other DNA repair glycosylases. | The enzyme uracil DNA glycosylase (UNG) excises unwanted uracil bases in, the genome using an extrahelical base recognition mechanism. Efficient, removal of uracil is essential for prevention of C-to-T transition, mutations arising from cytosine deamination, cytotoxic U*A pairs arising, from incorporation of dUTP in DNA, and for increasing immunoglobulin gene, diversity during the acquired immune response. A central event in all of, these UNG-mediated processes is the singling out of rare U*A or U*G base, pairs in a background of approximately 10(9) T*A or C*G base pairs in the, human genome. Here we establish for the human and Escherichia coli enzymes, that discrimination of thymine and uracil is initiated by thermally, induced opening of T*A and U*A base pairs and not by active participation, of the enzyme. Thus, base-pair dynamics has a critical role in the, genome-wide search for uracil, and may be involved in initial damage, recognition by other DNA repair glycosylases. | ||
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| - | ==Disease== | ||
| - | Known diseases associated with this structure: Immunodeficiency with hyper IgM, type 4 OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=191525 191525]] | ||
==About this Structure== | ==About this Structure== | ||
| - | 2OXM is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http:// | + | 2OXM is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Known structural/functional Site: <scene name='pdbsite=AC1:4mf Binding Site For Residue C 27'>AC1</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2OXM OCA]. |
==Reference== | ==Reference== | ||
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[[Category: uracil dna glycosylase]] | [[Category: uracil dna glycosylase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jan 23 12:36:48 2008'' |
Revision as of 10:36, 23 January 2008
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Crystal structure of a UNG2/modified DNA complex that represent a stabilized short-lived extrahelical state in ezymatic DNA base flipping
Overview
The enzyme uracil DNA glycosylase (UNG) excises unwanted uracil bases in, the genome using an extrahelical base recognition mechanism. Efficient, removal of uracil is essential for prevention of C-to-T transition, mutations arising from cytosine deamination, cytotoxic U*A pairs arising, from incorporation of dUTP in DNA, and for increasing immunoglobulin gene, diversity during the acquired immune response. A central event in all of, these UNG-mediated processes is the singling out of rare U*A or U*G base, pairs in a background of approximately 10(9) T*A or C*G base pairs in the, human genome. Here we establish for the human and Escherichia coli enzymes, that discrimination of thymine and uracil is initiated by thermally, induced opening of T*A and U*A base pairs and not by active participation, of the enzyme. Thus, base-pair dynamics has a critical role in the, genome-wide search for uracil, and may be involved in initial damage, recognition by other DNA repair glycosylases.
About this Structure
2OXM is a Protein complex structure of sequences from Homo sapiens. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Enzymatic capture of an extrahelical thymine in the search for uracil in DNA., Parker JB, Bianchet MA, Krosky DJ, Friedman JI, Amzel LM, Stivers JT, Nature. 2007 Sep 27;449(7161):433-7. Epub 2007 Aug 19. PMID:17704764
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