2pub: Difference between revisions
New page: left|200px<br /><applet load="2pub" size="450" color="white" frame="true" align="right" spinBox="true" caption="2pub, resolution 2.700Å" /> '''CRYSTAL STRUCTURE O... |
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[[Image:2pub.gif|left|200px]]<br /><applet load="2pub" size=" | [[Image:2pub.gif|left|200px]]<br /><applet load="2pub" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="2pub, resolution 2.700Å" /> | caption="2pub, resolution 2.700Å" /> | ||
'''CRYSTAL STRUCTURE OF THE LACI FAMILY MEMBER, PURR, BOUND TO DNA: MINOR GROOVE BINDING BY ALPHA HELICES'''<br /> | '''CRYSTAL STRUCTURE OF THE LACI FAMILY MEMBER, PURR, BOUND TO DNA: MINOR GROOVE BINDING BY ALPHA HELICES'''<br /> | ||
==Overview== | ==Overview== | ||
The three-dimensional structure of a ternary complex of the purine | The three-dimensional structure of a ternary complex of the purine repressor, PurR, bound to both its corepressor, hypoxanthine, and the 16-base pair purF operator site has been solved at 2.7 A resolution by x-ray crystallography. The bipartite structure of PurR consists of an amino-terminal DNA-binding domain and a larger carboxyl-terminal corepressor binding and dimerization domain that is similar to that of the bacterial periplasmic binding proteins. The DNA-binding domain contains a helix-turn-helix motif that makes base-specific contacts in the major groove of the DNA. Base contacts are also made by residues of symmetry-related alpha helices, the "hinge" helices, which bind deeply in the minor groove. Critical to hinge helix-minor groove binding is the intercalation of the side chains of Leu54 and its symmetry-related mate, Leu54', into the central CpG-base pair step. These residues thereby act as "leucine levers" to pry open the minor groove and kink the purF operator by 45 degrees. | ||
==About this Structure== | ==About this Structure== | ||
2PUB 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 ADE as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | 2PUB 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=ADE:'>ADE</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2PUB OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Choi, K | [[Category: Choi, K Y.]] | ||
[[Category: Schumacher, R | [[Category: Schumacher, R G.Brennan M A.]] | ||
[[Category: Zalkin, H.]] | [[Category: Zalkin, H.]] | ||
[[Category: ADE]] | [[Category: ADE]] | ||
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[[Category: dna-binding regulatory protein]] | [[Category: dna-binding regulatory protein]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:33:00 2008'' |
Revision as of 19:33, 21 February 2008
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CRYSTAL STRUCTURE OF THE LACI FAMILY MEMBER, PURR, BOUND TO DNA: MINOR GROOVE BINDING BY ALPHA HELICES
OverviewOverview
The three-dimensional structure of a ternary complex of the purine repressor, PurR, bound to both its corepressor, hypoxanthine, and the 16-base pair purF operator site has been solved at 2.7 A resolution by x-ray crystallography. The bipartite structure of PurR consists of an amino-terminal DNA-binding domain and a larger carboxyl-terminal corepressor binding and dimerization domain that is similar to that of the bacterial periplasmic binding proteins. The DNA-binding domain contains a helix-turn-helix motif that makes base-specific contacts in the major groove of the DNA. Base contacts are also made by residues of symmetry-related alpha helices, the "hinge" helices, which bind deeply in the minor groove. Critical to hinge helix-minor groove binding is the intercalation of the side chains of Leu54 and its symmetry-related mate, Leu54', into the central CpG-base pair step. These residues thereby act as "leucine levers" to pry open the minor groove and kink the purF operator by 45 degrees.
About this StructureAbout this Structure
2PUB is a Single protein structure of sequence from Escherichia coli with as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of LacI member, PurR, bound to DNA: minor groove binding by alpha helices., Schumacher MA, Choi KY, Zalkin H, Brennan RG, Science. 1994 Nov 4;266(5186):763-70. PMID:7973627
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