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2ho0
From Proteopedia
(New page: 200px<br /><applet load="2ho0" size="350" color="white" frame="true" align="right" spinBox="true" caption="2ho0, resolution 2.50Å" /> '''Structure of a Hyper...) |
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==Overview== | ==Overview== | ||
| - | The key event in the switch from lysogenic to lytic growth of phage lambda | + | The key event in the switch from lysogenic to lytic growth of phage lambda is the self-cleavage of lambda repressor, which is induced by the formation of a RecA-ssDNA-ATP filament at a site of DNA damage. Lambda repressor cleaves itself at the peptide bond between Ala111 and Gly112, but only when bound as a monomer to the RecA-ssDNA-ATP filament. Here we have designed a hyper-cleavable fragment of lambda repressor containing the hinge and C-terminal domain (residues 101-229), in which the monomer-monomer interface is disrupted by two point mutations and a deletion of seven residues at the C terminus. This fragment crystallizes as a monomer and its structure has been determined to 1.8 A resolution. The hinge region, which bears the cleavage site, is folded over the active site of the C-terminal oligomerization domain (CTD) but with the cleavage site flipped out and exposed to solvent. Thus, the structure represents a non-cleavable conformation of the repressor, but one that is poised for cleavage after modest rearrangements that are presumably stabilized by binding to RecA. The structure provides a unique snapshot of lambda repressor in a conformation that sheds light on how its self-cleavage is tempered in the absence of RecA, as well as a framework for interpreting previous genetic and biochemical data concerning the RecA-mediated cleavage reaction. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Bell, C | + | [[Category: Bell, C E.]] |
[[Category: Ndjonka, D.]] | [[Category: Ndjonka, D.]] | ||
[[Category: CA]] | [[Category: CA]] | ||
[[Category: virus/viral protein]] | [[Category: virus/viral protein]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:43:49 2008'' |
Revision as of 15:43, 21 February 2008
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Structure of a Hyper-cleavable Monomeric Fragment of Phage Lambda Repressor Containing the Cleavage Site Region
Overview
The key event in the switch from lysogenic to lytic growth of phage lambda is the self-cleavage of lambda repressor, which is induced by the formation of a RecA-ssDNA-ATP filament at a site of DNA damage. Lambda repressor cleaves itself at the peptide bond between Ala111 and Gly112, but only when bound as a monomer to the RecA-ssDNA-ATP filament. Here we have designed a hyper-cleavable fragment of lambda repressor containing the hinge and C-terminal domain (residues 101-229), in which the monomer-monomer interface is disrupted by two point mutations and a deletion of seven residues at the C terminus. This fragment crystallizes as a monomer and its structure has been determined to 1.8 A resolution. The hinge region, which bears the cleavage site, is folded over the active site of the C-terminal oligomerization domain (CTD) but with the cleavage site flipped out and exposed to solvent. Thus, the structure represents a non-cleavable conformation of the repressor, but one that is poised for cleavage after modest rearrangements that are presumably stabilized by binding to RecA. The structure provides a unique snapshot of lambda repressor in a conformation that sheds light on how its self-cleavage is tempered in the absence of RecA, as well as a framework for interpreting previous genetic and biochemical data concerning the RecA-mediated cleavage reaction.
About this Structure
2HO0 is a Single protein structure of sequence from Escherichia coli with as ligand. Full crystallographic information is available from OCA.
Reference
Structure of a hyper-cleavable monomeric fragment of phage lambda repressor containing the cleavage site region., Ndjonka D, Bell CE, J Mol Biol. 2006 Sep 22;362(3):479-89. Epub 2006 Jul 15. PMID:16934834
Page seeded by OCA on Thu Feb 21 17:43:49 2008
