1rh6
From Proteopedia
(New page: 200px<br /><applet load="1rh6" size="450" color="white" frame="true" align="right" spinBox="true" caption="1rh6, resolution 1.70Å" /> '''Bacteriophage Lambda...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1rh6.gif|left|200px]]<br /><applet load="1rh6" size=" | + | [[Image:1rh6.gif|left|200px]]<br /><applet load="1rh6" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1rh6, resolution 1.70Å" /> | caption="1rh6, resolution 1.70Å" /> | ||
'''Bacteriophage Lambda Excisionase (Xis)-DNA Complex'''<br /> | '''Bacteriophage Lambda Excisionase (Xis)-DNA Complex'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The excisionase (Xis) protein from bacteriophage lambda is the best | + | The excisionase (Xis) protein from bacteriophage lambda is the best characterized member of a large family of recombination directionality factors that control integrase-mediated DNA rearrangements. It triggers phage excision by cooperatively binding to sites X1 and X2 within the phage, bending DNA significantly and recruiting the phage-encoded integrase (Int) protein to site P2. We have determined the co-crystal structure of Xis with its X2 DNA-binding site at 1.7A resolution. Xis forms a unique winged-helix motif that interacts with the major and minor grooves of its binding site using an alpha-helix and an ordered beta-hairpin (wing), respectively. Recognition is achieved through an elaborate water-mediated hydrogen-bonding network at the major groove interface, while the preformed hairpin forms largely non-specific interactions with the minor groove. The structure of the complex provides insights into how Xis recruits Int cooperatively, and suggests a plausible mechanism by which it may distort longer DNA fragments significantly. It reveals a surface on the protein that is likely to mediate Xis-Xis interactions required for its cooperative binding to DNA. |
==About this Structure== | ==About this Structure== | ||
| - | 1RH6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Enterobacteria_phage_lambda Enterobacteria phage lambda]. Full crystallographic information is available from [http:// | + | 1RH6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Enterobacteria_phage_lambda Enterobacteria phage lambda]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1RH6 OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Cascio, D.]] | [[Category: Cascio, D.]] | ||
| - | [[Category: Clubb, R | + | [[Category: Clubb, R T.]] |
| - | [[Category: Johnson, R | + | [[Category: Johnson, R C.]] |
| - | [[Category: Sam, M | + | [[Category: Sam, M D.]] |
[[Category: 'winged'-helix protein]] | [[Category: 'winged'-helix protein]] | ||
[[Category: dna architectural protein]] | [[Category: dna architectural protein]] | ||
| Line 23: | Line 23: | ||
[[Category: site-specific dna recombination]] | [[Category: site-specific dna recombination]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:50:49 2008'' |
Revision as of 12:50, 21 February 2008
|
Bacteriophage Lambda Excisionase (Xis)-DNA Complex
Overview
The excisionase (Xis) protein from bacteriophage lambda is the best characterized member of a large family of recombination directionality factors that control integrase-mediated DNA rearrangements. It triggers phage excision by cooperatively binding to sites X1 and X2 within the phage, bending DNA significantly and recruiting the phage-encoded integrase (Int) protein to site P2. We have determined the co-crystal structure of Xis with its X2 DNA-binding site at 1.7A resolution. Xis forms a unique winged-helix motif that interacts with the major and minor grooves of its binding site using an alpha-helix and an ordered beta-hairpin (wing), respectively. Recognition is achieved through an elaborate water-mediated hydrogen-bonding network at the major groove interface, while the preformed hairpin forms largely non-specific interactions with the minor groove. The structure of the complex provides insights into how Xis recruits Int cooperatively, and suggests a plausible mechanism by which it may distort longer DNA fragments significantly. It reveals a surface on the protein that is likely to mediate Xis-Xis interactions required for its cooperative binding to DNA.
About this Structure
1RH6 is a Single protein structure of sequence from Enterobacteria phage lambda. Full crystallographic information is available from OCA.
Reference
Crystal structure of the excisionase-DNA complex from bacteriophage lambda., Sam MD, Cascio D, Johnson RC, Clubb RT, J Mol Biol. 2004 Apr 23;338(2):229-40. PMID:15066428
Page seeded by OCA on Thu Feb 21 14:50:49 2008
