2is6
From Proteopedia
(New page: 200px<br /><applet load="2is6" size="450" color="white" frame="true" align="right" spinBox="true" caption="2is6, resolution 2.20Å" /> '''Crystal structure of...) |
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| - | [[Image:2is6.gif|left|200px]]<br /><applet load="2is6" size=" | + | [[Image:2is6.gif|left|200px]]<br /><applet load="2is6" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2is6, resolution 2.20Å" /> | caption="2is6, resolution 2.20Å" /> | ||
'''Crystal structure of UvrD-DNA-ADPMgF3 ternary complex'''<br /> | '''Crystal structure of UvrD-DNA-ADPMgF3 ternary complex'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Helicases use the energy derived from nucleoside triphosphate hydrolysis | + | Helicases use the energy derived from nucleoside triphosphate hydrolysis to unwind double helices in essentially every metabolic pathway involving nucleic acids. Earlier crystal structures have suggested that DNA helicases translocate along a single-stranded DNA in an inchworm fashion. We report here a series of crystal structures of the UvrD helicase complexed with DNA and ATP hydrolysis intermediates. These structures reveal that ATP binding alone leads to unwinding of 1 base pair by directional rotation and translation of the DNA duplex, and ADP and Pi release leads to translocation of the developing single strand. Thus DNA unwinding is achieved by a two-part power stroke in a combined wrench-and-inchworm mechanism. The rotational angle and translational distance of DNA define the unwinding step to be 1 base pair per ATP hydrolyzed. Finally, a gateway for ssDNA translocation and an alternative strand-displacement mode may explain the varying step sizes reported previously. |
==About this Structure== | ==About this Structure== | ||
| - | 2IS6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with MG, MGF, ADP and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 2IS6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=MGF:'>MGF</scene>, <scene name='pdbligand=ADP:'>ADP</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2IS6 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Lee, J | + | [[Category: Lee, J Y.]] |
[[Category: Yang, W.]] | [[Category: Yang, W.]] | ||
[[Category: ADP]] | [[Category: ADP]] | ||
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[[Category: dna helicase]] | [[Category: dna helicase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:55:19 2008'' |
Revision as of 15:55, 21 February 2008
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Crystal structure of UvrD-DNA-ADPMgF3 ternary complex
Overview
Helicases use the energy derived from nucleoside triphosphate hydrolysis to unwind double helices in essentially every metabolic pathway involving nucleic acids. Earlier crystal structures have suggested that DNA helicases translocate along a single-stranded DNA in an inchworm fashion. We report here a series of crystal structures of the UvrD helicase complexed with DNA and ATP hydrolysis intermediates. These structures reveal that ATP binding alone leads to unwinding of 1 base pair by directional rotation and translation of the DNA duplex, and ADP and Pi release leads to translocation of the developing single strand. Thus DNA unwinding is achieved by a two-part power stroke in a combined wrench-and-inchworm mechanism. The rotational angle and translational distance of DNA define the unwinding step to be 1 base pair per ATP hydrolyzed. Finally, a gateway for ssDNA translocation and an alternative strand-displacement mode may explain the varying step sizes reported previously.
About this Structure
2IS6 is a Single protein structure of sequence from Escherichia coli with , , and as ligands. Full crystallographic information is available from OCA.
Reference
UvrD helicase unwinds DNA one base pair at a time by a two-part power stroke., Lee JY, Yang W, Cell. 2006 Dec 29;127(7):1349-60. PMID:17190599
Page seeded by OCA on Thu Feb 21 17:55:19 2008
Categories: Escherichia coli | Single protein | Lee, J Y. | Yang, W. | ADP | GOL | MG | MGF | Dna helicase
