2ffa: Difference between revisions

Revision as of 18:20, 21 February 2008

Crystal structure of ABC-ATPase H662A of the ABC-transporter HlyB in complex with ADP

OverviewOverview

The ATP-binding cassette (ABC)-transporter haemolysin (Hly)B, a central element of a Type I secretion machinery, acts in concert with two additional proteins in Escherichia coli to translocate the toxin HlyA directly from the cytoplasm to the exterior. The basic set of crystal structures necessary to describe the catalytic cycle of the isolated HlyB-NBD (nucleotide-binding domain) has now been completed. This allowed a detailed analysis with respect to hinge regions, functionally important key residues and potential energy storage devices that revealed many novel features. These include a structural asymmetry within the ATP dimer that was significantly enhanced in the presence of Mg2+, indicating a possible functional asymmetry in the form of one open and one closed phosphate exit tunnel. Guided by the structural analysis, we identified two amino acids, closing one tunnel by an apparent salt bridge. Mutation of these residues abolished ATP-dependent cooperativity of the NBDs. The implications of these new findings for the coupling of ATP binding and hydrolysis to functional activity are discussed.

About this StructureAbout this Structure

2FFA is a Single protein structure of sequence from Escherichia coli with and as ligands. Full crystallographic information is available from OCA.

ReferenceReference

A structural analysis of asymmetry required for catalytic activity of an ABC-ATPase domain dimer., Zaitseva J, Oswald C, Jumpertz T, Jenewein S, Wiedenmann A, Holland IB, Schmitt L, EMBO J. 2006 Jul 26;25(14):3432-43. Epub 2006 Jul 6. PMID:16858415

Page seeded by OCA on Thu Feb 21 17:20:51 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

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-[[Image:2ffa.gif|left|200px]]<br /><applet load="2ffa" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:2ffa.gif|left|200px]]<br /><applet load="2ffa" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="2ffa, resolution 1.70&Aring;" />
 '''Crystal structure of ABC-ATPase H662A of the ABC-transporter HlyB in complex with ADP'''<br />
 ==Overview==
-The ATP-binding cassette (ABC)-transporter haemolysin (Hly)B, a central, element of a Type I secretion machinery, acts in concert with two, additional proteins in Escherichia coli to translocate the toxin HlyA, directly from the cytoplasm to the exterior. The basic set of crystal, structures necessary to describe the catalytic cycle of the isolated, HlyB-NBD (nucleotide-binding domain) has now been completed. This allowed, a detailed analysis with respect to hinge regions, functionally important, key residues and potential energy storage devices that revealed many novel, features. These include a structural asymmetry within the ATP dimer that, was significantly enhanced in the presence of Mg2+, indicating a possible, functional asymmetry in the form of one open and one closed phosphate exit, tunnel. Guided by the structural analysis, we identified two amino acids, closing one tunnel by an apparent salt bridge. Mutation of these residues, abolished ATP-dependent cooperativity of the NBDs. The implications of, these new findings for the coupling of ATP binding and hydrolysis to, functional activity are discussed.
+The ATP-binding cassette (ABC)-transporter haemolysin (Hly)B, a central element of a Type I secretion machinery, acts in concert with two additional proteins in Escherichia coli to translocate the toxin HlyA directly from the cytoplasm to the exterior. The basic set of crystal structures necessary to describe the catalytic cycle of the isolated HlyB-NBD (nucleotide-binding domain) has now been completed. This allowed a detailed analysis with respect to hinge regions, functionally important key residues and potential energy storage devices that revealed many novel features. These include a structural asymmetry within the ATP dimer that was significantly enhanced in the presence of Mg2+, indicating a possible functional asymmetry in the form of one open and one closed phosphate exit tunnel. Guided by the structural analysis, we identified two amino acids, closing one tunnel by an apparent salt bridge. Mutation of these residues abolished ATP-dependent cooperativity of the NBDs. The implications of these new findings for the coupling of ATP binding and hydrolysis to functional activity are discussed.
 ==About this Structure==
-FFA 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 ADP and MPD as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2FFA OCA].
+FFA 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=ADP:'>ADP</scene> and <scene name='pdbligand=MPD:'>MPD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FFA OCA].
 ==Reference==
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 [[Category: Escherichia coli]]
 [[Category: Single protein]]
-[[Category: Holland, I.B.]]
+[[Category: Holland, I B.]]
 [[Category: Jenewein, S.]]
 [[Category: Jumpertz, T.]]
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 [[Category: atpase]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 10:31:49 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:20:51 2008''