3pjr: Difference between revisions

Revision as of 20:10, 21 February 2008

HELICASE SUBSTRATE COMPLEX

OverviewOverview

We have determined two different structures of PcrA DNA helicase complexed with the same single strand tailed DNA duplex, providing snapshots of different steps on the catalytic pathway. One of the structures is of a complex with a nonhydrolyzable analog of ATP and is thus a "substrate" complex. The other structure contains a bound sulphate ion that sits in a position equivalent to that occupied by the phosphate ion produced after ATP hydrolysis, thereby mimicking a "product" complex. In both complexes, the protein is monomeric. Large and distinct conformational changes occur on binding DNA and the nucleotide cofactor. Taken together, these structures provide evidence against an "active rolling" model for helicase action but are instead consistent with an "inchworm" mechanism.

About this StructureAbout this Structure

3PJR is a Single protein structure of sequence from Geobacillus stearothermophilus with as ligand. Full crystallographic information is available from OCA.

ReferenceReference

Crystal structures of complexes of PcrA DNA helicase with a DNA substrate indicate an inchworm mechanism., Velankar SS, Soultanas P, Dillingham MS, Subramanya HS, Wigley DB, Cell. 1999 Apr 2;97(1):75-84. PMID:10199404

Page seeded by OCA on Thu Feb 21 19:10:53 2008

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

OCA

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-[[Image:3pjr.gif|left|200px]]<br /><applet load="3pjr" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:3pjr.gif|left|200px]]<br /><applet load="3pjr" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="3pjr, resolution 3.3&Aring;" />
 '''HELICASE SUBSTRATE COMPLEX'''<br />
 ==Overview==
-We have determined two different structures of PcrA DNA helicase complexed, with the same single strand tailed DNA duplex, providing snapshots of, different steps on the catalytic pathway. One of the structures is of a, complex with a nonhydrolyzable analog of ATP and is thus a "substrate", complex. The other structure contains a bound sulphate ion that sits in a, position equivalent to that occupied by the phosphate ion produced after, ATP hydrolysis, thereby mimicking a "product" complex. In both complexes, the protein is monomeric. Large and distinct conformational changes occur, on binding DNA and the nucleotide cofactor. Taken together, these, structures provide evidence against an "active rolling" model for helicase, action but are instead consistent with an "inchworm" mechanism.
+We have determined two different structures of PcrA DNA helicase complexed with the same single strand tailed DNA duplex, providing snapshots of different steps on the catalytic pathway. One of the structures is of a complex with a nonhydrolyzable analog of ATP and is thus a "substrate" complex. The other structure contains a bound sulphate ion that sits in a position equivalent to that occupied by the phosphate ion produced after ATP hydrolysis, thereby mimicking a "product" complex. In both complexes, the protein is monomeric. Large and distinct conformational changes occur on binding DNA and the nucleotide cofactor. Taken together, these structures provide evidence against an "active rolling" model for helicase action but are instead consistent with an "inchworm" mechanism.
 ==About this Structure==
-PJR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Geobacillus_stearothermophilus Geobacillus stearothermophilus] with ATP as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=3PJR OCA].
+PJR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Geobacillus_stearothermophilus Geobacillus stearothermophilus] with <scene name='pdbligand=ATP:'>ATP</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3PJR OCA].
 ==Reference==
@@ Line 13: / Line 13: @@
 [[Category: Geobacillus stearothermophilus]]
 [[Category: Single protein]]
-[[Category: Dillingham, M.S.]]
+[[Category: Dillingham, M S.]]
 [[Category: Soultanas, P.]]
-[[Category: Subramanya, H.S.]]
+[[Category: Subramanya, H S.]]
-[[Category: Velankar, S.S.]]
+[[Category: Velankar, S S.]]
-[[Category: Wigley, D.B.]]
+[[Category: Wigley, D B.]]
 [[Category: ATP]]
 [[Category: helicase]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 19:56:12 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:10:53 2008''