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2ecs
From Proteopedia
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==About this Structure== | ==About this Structure== | ||
| - | 2ECS 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] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=ACT:'>ACT</scene>, <scene name='pdbligand=CL:'>CL</scene> and <scene name='pdbligand=LI:'>LI</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ECS OCA]. | + | 2ECS 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] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=ACT:'>ACT</scene>, <scene name='pdbligand=CL:'>CL</scene> and <scene name='pdbligand=LI:'>LI</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Sites: <scene name='pdbsite=AC1:So4+Binding+Site+For+Residue+B+201'>AC1</scene>, <scene name='pdbsite=AC2:So4+Binding+Site+For+Residue+B+202'>AC2</scene>, <scene name='pdbsite=AC3:So4+Binding+Site+For+Residue+B+203'>AC3</scene>, <scene name='pdbsite=AC4:So4+Binding+Site+For+Residue+A+204'>AC4</scene>, <scene name='pdbsite=AC5:Act+Binding+Site+For+Residue+A+205'>AC5</scene>, <scene name='pdbsite=AC6:Act+Binding+Site+For+Residue+B+206'>AC6</scene>, <scene name='pdbsite=AC7:Act+Binding+Site+For+Residue+B+207'>AC7</scene>, <scene name='pdbsite=AC8:Act+Binding+Site+For+Residue+A+208'>AC8</scene>, <scene name='pdbsite=AC9:Cl+Binding+Site+For+Residue+B+209'>AC9</scene>, <scene name='pdbsite=BC1:Li+Binding+Site+For+Residue+B+210'>BC1</scene> and <scene name='pdbsite=BC2:Li+Binding+Site+For+Residue+B+211'>BC2</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ECS OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Cordes, M.H.]] | [[Category: Cordes, M.H.]] | ||
[[Category: Hall, B.M.]] | [[Category: Hall, B.M.]] | ||
| - | [[Category: Horton, N.C.]] | ||
[[Category: Roberts, S.A.]] | [[Category: Roberts, S.A.]] | ||
[[Category: ACT]] | [[Category: ACT]] | ||
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[[Category: transcription factor]] | [[Category: transcription factor]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Feb 6 | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Feb 6 17:28:03 2008'' |
Revision as of 15:28, 6 February 2008
|
Lambda Cro mutant Q27P/A29S/K32Q at 1.4 A in space group C2
Overview
Previously reported crystal structures of free and DNA-bound dimers of, lambda Cro differ strongly (about 4 A backbone rmsd), suggesting both, flexibility of the dimer interface and induced-fit protein structure, changes caused by sequence-specific DNA binding. Here, we present two, crystal structures, in space groups P3(2)21 and C2 at 1.35 and 1.40 A, resolution, respectively, of a variant of lambda Cro with three mutations, in its recognition helix (Q27P/A29S/K32Q, or PSQ for short). One dimer, structure (P3(2)21; PSQ form 1) resembles the DNA-bound wild-type Cro, dimer (1.0 A backbone rmsd), while the other (C2; PSQ form 2) resembles, neither unbound (3.6 A) nor bound (2.4 A) wild-type Cro. Both PSQ form 2, and unbound wild-type dimer crystals have a similar interdimer beta-sheet, interaction between the beta1 strands at the edges of the dimer. In the, former, an infinite, open beta-structure along one crystal axis results, while in the latter, a closed tetrameric barrel is formed. Neither the, DNA-bound wild-type structure nor PSQ form 1 contains these interdimer, interactions. We propose that beta-sheet superstructures resulting from, crystal contact interactions distort Cro dimers from their preferred, solution conformation, which actually resembles the DNA-bound structure., These results highlight the remarkable flexibility of lambda Cro but also, suggest that sequence-specific DNA binding may not induce large changes in, the protein structure.
About this Structure
2ECS is a Single protein structure of sequence from Enterobacteria phage lambda with , , and as ligands. Known structural/functional Sites: , , , , , , , , , and . Full crystallographic information is available from OCA.
Reference
Two structures of a lambda Cro variant highlight dimer flexibility but disfavor major dimer distortions upon specific binding of cognate DNA., Hall BM, Roberts SA, Heroux A, Cordes MH, J Mol Biol. 2008 Jan 18;375(3):802-11. Epub 2007 Nov 6. PMID:18054042
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