2oxm
From Proteopedia
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==Overview== | ==Overview== | ||
| - | The enzyme uracil DNA glycosylase (UNG) excises unwanted uracil bases in | + | 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]. 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]. | + | 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: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Amzel, L | + | [[Category: Amzel, L M.]] |
| - | [[Category: Bianchet, M | + | [[Category: Bianchet, M A.]] |
| - | [[Category: J | + | [[Category: J T., Stivers.]] |
| - | [[Category: Krosky, D | + | [[Category: Krosky, D J.]] |
[[Category: enzyme dna complex]] | [[Category: enzyme dna complex]] | ||
[[Category: hydrolase/dna complex]] | [[Category: hydrolase/dna complex]] | ||
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[[Category: uracil dna glycosylase]] | [[Category: uracil dna glycosylase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:23:41 2008'' |
Revision as of 16:23, 21 February 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
Contents |
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.
Disease
Known diseases associated with this structure: Immunodeficiency with hyper IgM, type 4 OMIM:[191525]
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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