1m74: Difference between revisions

Revision as of 00:43, 3 May 2008

Crystal structure of Mg-ADP-bound SecA from Bacillus subtilis

OverviewOverview

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 StructureAbout this Structure

1M74 is a Single protein structure of sequence from Bacillus subtilis. Full crystallographic information is available from OCA.

ReferenceReference

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 Page seeded by OCA on Sat May 3 00:43:04 2008

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OCA

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 [[Image:1m74.gif|left|200px]]
- {{Structure
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+The line below this paragraph, containing "STRUCTURE_1m74", creates the "Structure Box" on the page.
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-|GENE= Div ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1423 Bacillus subtilis])
+-->
-|DOMAIN=
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-|RELATEDENTRY=[[1m6n|1M6N]]
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1m74 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1m74 OCA], [http://www.ebi.ac.uk/pdbsum/1m74 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1m74 RCSB]</span>
-}}
 '''Crystal structure of Mg-ADP-bound SecA from Bacillus subtilis'''
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 [[Category: Oliver, D B.]]
 [[Category: Weinkauf, S.]]
-[[Category: atpase]]
+[[Category: Atpase]]
-[[Category: helicase family structure]]
+[[Category: Helicase family structure]]
-[[Category: mechanochemisty]]
+[[Category: Mechanochemisty]]
-[[Category: protein translocation]]
+[[Category: Protein translocation]]
-[[Category: transmembrane transport]]
+[[Category: Transmembrane transport]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May  3 00:43:04 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 22:12:14 2008''