1m74
From Proteopedia
(New page: 200px<br /><applet load="1m74" size="450" color="white" frame="true" align="right" spinBox="true" caption="1m74, resolution 3.00Å" /> '''Crystal structure of...) |
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| - | [[Image:1m74.gif|left|200px]]<br /><applet load="1m74" size=" | + | [[Image:1m74.gif|left|200px]]<br /><applet load="1m74" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1m74, resolution 3.00Å" /> | caption="1m74, resolution 3.00Å" /> | ||
'''Crystal structure of Mg-ADP-bound SecA from Bacillus subtilis'''<br /> | '''Crystal structure of Mg-ADP-bound SecA from Bacillus subtilis'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The SecA adenosine triphosphatase (ATPase) mediates extrusion of the amino | + | The SecA adenosine triphosphatase (ATPase) mediates extrusion of the amino termini of secreted proteins from the eubacterial cytosol based on cycles of reversible binding to the SecYEG translocon. We have determined the crystal structure of SecA with and without magnesium-adenosine diphosphate bound to the high-affinity ATPase site at 3.0 and 2.7 angstrom resolution, respectively. Candidate sites for preprotein binding are located on a surface containing the SecA epitopes exposed to the periplasm upon binding to SecYEG and are thus positioned to deliver preprotein to SecYEG. Comparisons with structurally related ATPases, including superfamily I and II ATP-dependent helicases, suggest that the interaction geometry of the tandem motor domains in SecA is modulated by nucleotide binding, which is shown by fluorescence anisotropy experiments to reverse an endothermic domain-dissociation reaction hypothesized to gate binding to SecYEG. |
==About this Structure== | ==About this Structure== | ||
| - | 1M74 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] with MG, SO4 and ADP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1M74 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] with <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=ADP:'>ADP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1M74 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Deisenhofer, J.]] | [[Category: Deisenhofer, J.]] | ||
| - | [[Category: Fak, J | + | [[Category: Fak, J J.]] |
[[Category: Henry, L.]] | [[Category: Henry, L.]] | ||
| - | [[Category: Hunt, J | + | [[Category: Hunt, J F.]] |
[[Category: McNicholas, P.]] | [[Category: McNicholas, P.]] | ||
| - | [[Category: Oliver, D | + | [[Category: Oliver, D B.]] |
[[Category: Weinkauf, S.]] | [[Category: Weinkauf, S.]] | ||
[[Category: ADP]] | [[Category: ADP]] | ||
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[[Category: protein translocation; atpase; transmembrane transport; helicase family structure; mechanochemisty]] | [[Category: protein translocation; atpase; transmembrane transport; helicase family structure; mechanochemisty]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:52:11 2008'' |
Revision as of 11:52, 21 February 2008
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Crystal structure of Mg-ADP-bound SecA from Bacillus subtilis
Overview
The SecA adenosine triphosphatase (ATPase) mediates extrusion of the amino termini of secreted proteins from the eubacterial cytosol based on cycles of reversible binding to the SecYEG translocon. We have determined the crystal structure of SecA with and without magnesium-adenosine diphosphate bound to the high-affinity ATPase site at 3.0 and 2.7 angstrom resolution, respectively. Candidate sites for preprotein binding are located on a surface containing the SecA epitopes exposed to the periplasm upon binding to SecYEG and are thus positioned to deliver preprotein to SecYEG. Comparisons with structurally related ATPases, including superfamily I and II ATP-dependent helicases, suggest that the interaction geometry of the tandem motor domains in SecA is modulated by nucleotide binding, which is shown by fluorescence anisotropy experiments to reverse an endothermic domain-dissociation reaction hypothesized to gate binding to SecYEG.
About this Structure
1M74 is a Single protein structure of sequence from Bacillus subtilis with , and as ligands. Full crystallographic information is available from OCA.
Reference
Nucleotide control of interdomain interactions in the conformational reaction cycle of SecA., Hunt JF, Weinkauf S, Henry L, Fak JJ, McNicholas P, Oliver DB, Deisenhofer J, Science. 2002 Sep 20;297(5589):2018-26. PMID:12242434
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