1no1
From Proteopedia
(New page: 200px<br /><applet load="1no1" size="450" color="white" frame="true" align="right" spinBox="true" caption="1no1, resolution 2.40Å" /> '''Structure of truncat...) |
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| - | [[Image:1no1.jpg|left|200px]]<br /><applet load="1no1" size=" | + | [[Image:1no1.jpg|left|200px]]<br /><applet load="1no1" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1no1, resolution 2.40Å" /> | caption="1no1, resolution 2.40Å" /> | ||
'''Structure of truncated variant of B.subtilis SPP1 phage G39P helicase loader/inhibitor protein'''<br /> | '''Structure of truncated variant of B.subtilis SPP1 phage G39P helicase loader/inhibitor protein'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The Bacillus subtilis SPP1 phage-encoded protein G39P is a loader and | + | The Bacillus subtilis SPP1 phage-encoded protein G39P is a loader and inhibitor of the phage G40P replicative helicase involved in the initiation of DNA replication. We have carried out a full x-ray crystallographic and preliminary NMR analysis of G39P and functional studies of the protein, including assays for helicase binding by a number of truncated mutant forms, in an effort to improve our understanding of how it both interacts with the helicase and with the phage replisome organizer, G38P. Our structural analyses reveal that G39P has a completely unexpected bipartite structure comprising a folded N-terminal domain and an essentially unfolded C-terminal domain. Although G39P has been shown to bind its G40P target with a 6:6 stoichiometry, our crystal structure and other biophysical characterization data reveal that the protein probably exists predominantly as a monomer in solution. The G39P protein is proteolytically sensitive, and our binding assays show that the C-terminal domain is essential for helicase interaction and that removal of just the 14 C-terminal residues abolishes interaction with the helicase in vitro. We propose a number of possible scenarios in which the flexibility of the C-terminal domain of G39P and its proteolytic sensitivity may have important roles for the function of G39P in vivo that are consistent with other data on SPP1 phage DNA replication. |
==About this Structure== | ==About this Structure== | ||
| - | 1NO1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_phage_sp82 Bacillus phage sp82]. Full crystallographic information is available from [http:// | + | 1NO1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_phage_sp82 Bacillus phage sp82]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NO1 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Bacillus phage sp82]] | [[Category: Bacillus phage sp82]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Alonso, J | + | [[Category: Alonso, J C.]] |
| - | [[Category: Ashcroft, A | + | [[Category: Ashcroft, A E.]] |
[[Category: Ayora, S.]] | [[Category: Ayora, S.]] | ||
[[Category: Bailey, S.]] | [[Category: Bailey, S.]] | ||
| - | [[Category: Baron, A | + | [[Category: Baron, A J.]] |
[[Category: Mesa, P.]] | [[Category: Mesa, P.]] | ||
| - | [[Category: Rafferty, J | + | [[Category: Rafferty, J B.]] |
| - | [[Category: Sedelnikova, S | + | [[Category: Sedelnikova, S E.]] |
| - | [[Category: Waltho, J | + | [[Category: Waltho, J P.]] |
[[Category: helical; bipartite; natively unfolded domain]] | [[Category: helical; bipartite; natively unfolded domain]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:08:11 2008'' |
Revision as of 12:08, 21 February 2008
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Structure of truncated variant of B.subtilis SPP1 phage G39P helicase loader/inhibitor protein
Overview
The Bacillus subtilis SPP1 phage-encoded protein G39P is a loader and inhibitor of the phage G40P replicative helicase involved in the initiation of DNA replication. We have carried out a full x-ray crystallographic and preliminary NMR analysis of G39P and functional studies of the protein, including assays for helicase binding by a number of truncated mutant forms, in an effort to improve our understanding of how it both interacts with the helicase and with the phage replisome organizer, G38P. Our structural analyses reveal that G39P has a completely unexpected bipartite structure comprising a folded N-terminal domain and an essentially unfolded C-terminal domain. Although G39P has been shown to bind its G40P target with a 6:6 stoichiometry, our crystal structure and other biophysical characterization data reveal that the protein probably exists predominantly as a monomer in solution. The G39P protein is proteolytically sensitive, and our binding assays show that the C-terminal domain is essential for helicase interaction and that removal of just the 14 C-terminal residues abolishes interaction with the helicase in vitro. We propose a number of possible scenarios in which the flexibility of the C-terminal domain of G39P and its proteolytic sensitivity may have important roles for the function of G39P in vivo that are consistent with other data on SPP1 phage DNA replication.
About this Structure
1NO1 is a Single protein structure of sequence from Bacillus phage sp82. Full crystallographic information is available from OCA.
Reference
Structural analysis of Bacillus subtilis SPP1 phage helicase loader protein G39P., Bailey S, Sedelnikova SE, Mesa P, Ayora S, Waltho JP, Ashcroft AE, Baron AJ, Alonso JC, Rafferty JB, J Biol Chem. 2003 Apr 25;278(17):15304-12. Epub 2003 Feb 13. PMID:12588876
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