1f44
From Proteopedia
(New page: 200px<br /><applet load="1f44" size="450" color="white" frame="true" align="right" spinBox="true" caption="1f44, resolution 2.05Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1f44.gif|left|200px]]<br /><applet load="1f44" size=" | + | [[Image:1f44.gif|left|200px]]<br /><applet load="1f44" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1f44, resolution 2.05Å" /> | caption="1f44, resolution 2.05Å" /> | ||
'''CRYSTAL STRUCTURE OF TRIMERIC CRE RECOMBINASE-LOX COMPLEX'''<br /> | '''CRYSTAL STRUCTURE OF TRIMERIC CRE RECOMBINASE-LOX COMPLEX'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structure of a novel Cre-Lox synapse was solved using phases | + | The crystal structure of a novel Cre-Lox synapse was solved using phases from multiple isomorphous replacement and anomalous scattering, and refined to 2.05 A resolution. In this complex, a symmetric protein trimer is bound to a Y-shaped three-way DNA junction, a marked departure from the pseudo-4-fold symmetrical tetramer associated with Cre-mediated LoxP recombination. The three-way DNA junction was accommodated by a simple kink without significant distortion of the adjoining DNA duplexes. Although the mean angle between DNA arms in the Y and X structures was similar, adjacent Cre trimer subunits rotated 29 degrees relative to those in the tetramers. This rotation was accommodated at the protein-protein and DNA-DNA interfaces by interactions that are "quasi-equivalent" to those in the tetramer, analogous to packing differences of chemically identical viral subunits at non-equivalent positions in icosahedral capsids. This structural quasi-equivalence extends to function as Cre can bind to, cleave and perform strand transfer with a three-way Lox substrate. The structure explains the dual recognition of three and four-way junctions by site-specific recombinases as being due to shared structural features between the differently branched substrates and plasticity of the protein-protein interfaces. To our knowledge, this is the first direct demonstration of quasi-equivalence in both the assembly and function of an oligomeric enzyme. |
==About this Structure== | ==About this Structure== | ||
| - | 1F44 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Enterobacteria_phage_p21 Enterobacteria phage p21]. Full crystallographic information is available from [http:// | + | 1F44 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Enterobacteria_phage_p21 Enterobacteria phage p21]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1F44 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Enterobacteria phage p21]] | [[Category: Enterobacteria phage p21]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Baldwin, E | + | [[Category: Baldwin, E P.]] |
| - | [[Category: Woods, K | + | [[Category: Woods, K C.]] |
[[Category: branched dna]] | [[Category: branched dna]] | ||
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
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[[Category: y-junction]] | [[Category: y-junction]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:34:40 2008'' |
Revision as of 10:34, 21 February 2008
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CRYSTAL STRUCTURE OF TRIMERIC CRE RECOMBINASE-LOX COMPLEX
Overview
The crystal structure of a novel Cre-Lox synapse was solved using phases from multiple isomorphous replacement and anomalous scattering, and refined to 2.05 A resolution. In this complex, a symmetric protein trimer is bound to a Y-shaped three-way DNA junction, a marked departure from the pseudo-4-fold symmetrical tetramer associated with Cre-mediated LoxP recombination. The three-way DNA junction was accommodated by a simple kink without significant distortion of the adjoining DNA duplexes. Although the mean angle between DNA arms in the Y and X structures was similar, adjacent Cre trimer subunits rotated 29 degrees relative to those in the tetramers. This rotation was accommodated at the protein-protein and DNA-DNA interfaces by interactions that are "quasi-equivalent" to those in the tetramer, analogous to packing differences of chemically identical viral subunits at non-equivalent positions in icosahedral capsids. This structural quasi-equivalence extends to function as Cre can bind to, cleave and perform strand transfer with a three-way Lox substrate. The structure explains the dual recognition of three and four-way junctions by site-specific recombinases as being due to shared structural features between the differently branched substrates and plasticity of the protein-protein interfaces. To our knowledge, this is the first direct demonstration of quasi-equivalence in both the assembly and function of an oligomeric enzyme.
About this Structure
1F44 is a Single protein structure of sequence from Enterobacteria phage p21. Full crystallographic information is available from OCA.
Reference
Quasi-equivalence in site-specific recombinase structure and function: crystal structure and activity of trimeric Cre recombinase bound to a three-way Lox DNA junction., Woods KC, Martin SS, Chu VC, Baldwin EP, J Mol Biol. 2001 Oct 12;313(1):49-69. PMID:11601846
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