1xu4
From Proteopedia
(New page: 200px<br /><applet load="1xu4" size="450" color="white" frame="true" align="right" spinBox="true" caption="1xu4, resolution 2.40Å" /> '''ATPASE IN COMPLEX WI...) |
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- | [[Image:1xu4.gif|left|200px]]<br /><applet load="1xu4" size=" | + | [[Image:1xu4.gif|left|200px]]<br /><applet load="1xu4" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1xu4, resolution 2.40Å" /> | caption="1xu4, resolution 2.40Å" /> | ||
'''ATPASE IN COMPLEX WITH AMP-PNP, MAGNESIUM AND POTASSIUM CO-F'''<br /> | '''ATPASE IN COMPLEX WITH AMP-PNP, MAGNESIUM AND POTASSIUM CO-F'''<br /> | ||
==Overview== | ==Overview== | ||
- | Homologous gene recombination is crucial for the repair of DNA. A | + | Homologous gene recombination is crucial for the repair of DNA. A superfamily of recombinases facilitate a central strand exchange reaction in the repair process. This reaction is initiated by coating single-stranded DNA (ssDNA) with recombinases in the presence of ATP and Mg(2+) co-factors to form helical nucleoprotein filaments with elevated ATPase and strand invasion activities. At the amino acid sequence level, archaeal RadA and Rad51 and eukaryal Rad51 and meiosis-specific DMC1 form a closely related group of recombinases distinct from bacterial RecA. Unlike the extensively studied Escherichia coli RecA (EcRecA), increasing evidences on yeast and human recombinases imply that their optimal activities are dependent on the presence of a monovalent cation, particularly potassium. Here we present the finding that archaeal RadA from Methanococcus voltae (MvRadA) is a stringent potassium-dependent ATPase, and the crystal structure of this protein in complex with the non-hydrolyzable ATP analog adenosine 5'-(beta,gamma-iminotriphosphate), Mg(2+), and K(+) at 2.4 A resolution. Potassium triggered an in situ conformational change in the ssDNA-binding L2 region concerted with incorporation of two potassium ions at the ATPase site in the RadA crystals preformed in K(+)-free medium. Both potassium ions were observed in contact with the gamma-phosphate of the ATP analog, implying a direct role by the monovalent cations in stimulating the ATPase activity. Cross-talk between the ATPase site and the ssDNA-binding L2 region visualized in the MvRadA structure provides an explanation to the co-factor-induced allosteric effect on RecA-like recombinases. |
==About this Structure== | ==About this Structure== | ||
- | 1XU4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanococcus_voltae Methanococcus voltae] with MG, K and ANP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1XU4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanococcus_voltae Methanococcus voltae] with <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=K:'>K</scene> and <scene name='pdbligand=ANP:'>ANP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XU4 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: He, Y.]] | [[Category: He, Y.]] | ||
[[Category: Luo, Y.]] | [[Category: Luo, Y.]] | ||
- | [[Category: Moya, I | + | [[Category: Moya, I A.]] |
[[Category: Qian, X.]] | [[Category: Qian, X.]] | ||
[[Category: Wu, Y.]] | [[Category: Wu, Y.]] | ||
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[[Category: protein-atp complex]] | [[Category: protein-atp complex]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:58:40 2008'' |
Revision as of 13:58, 21 February 2008
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ATPASE IN COMPLEX WITH AMP-PNP, MAGNESIUM AND POTASSIUM CO-F
Overview
Homologous gene recombination is crucial for the repair of DNA. A superfamily of recombinases facilitate a central strand exchange reaction in the repair process. This reaction is initiated by coating single-stranded DNA (ssDNA) with recombinases in the presence of ATP and Mg(2+) co-factors to form helical nucleoprotein filaments with elevated ATPase and strand invasion activities. At the amino acid sequence level, archaeal RadA and Rad51 and eukaryal Rad51 and meiosis-specific DMC1 form a closely related group of recombinases distinct from bacterial RecA. Unlike the extensively studied Escherichia coli RecA (EcRecA), increasing evidences on yeast and human recombinases imply that their optimal activities are dependent on the presence of a monovalent cation, particularly potassium. Here we present the finding that archaeal RadA from Methanococcus voltae (MvRadA) is a stringent potassium-dependent ATPase, and the crystal structure of this protein in complex with the non-hydrolyzable ATP analog adenosine 5'-(beta,gamma-iminotriphosphate), Mg(2+), and K(+) at 2.4 A resolution. Potassium triggered an in situ conformational change in the ssDNA-binding L2 region concerted with incorporation of two potassium ions at the ATPase site in the RadA crystals preformed in K(+)-free medium. Both potassium ions were observed in contact with the gamma-phosphate of the ATP analog, implying a direct role by the monovalent cations in stimulating the ATPase activity. Cross-talk between the ATPase site and the ssDNA-binding L2 region visualized in the MvRadA structure provides an explanation to the co-factor-induced allosteric effect on RecA-like recombinases.
About this Structure
1XU4 is a Single protein structure of sequence from Methanococcus voltae with , and as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of an ATPase-active form of Rad51 homolog from Methanococcus voltae. Insights into potassium dependence., Wu Y, Qian X, He Y, Moya IA, Luo Y, J Biol Chem. 2005 Jan 7;280(1):722-8. Epub 2004 Nov 10. PMID:15537659
Page seeded by OCA on Thu Feb 21 15:58:40 2008
Categories: Methanococcus voltae | Single protein | He, Y. | Luo, Y. | Moya, I A. | Qian, X. | Wu, Y. | ANP | K | MG | Atpase | Co-factors | Potassium-dependence | Protein-atp complex