Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 22.21 kDa 
• Atom Count: 1544 
• Modelled Residue Count: 190 
• Deposited Residue Count: 190 
• Unique protein chains: 1

1XSX

NMR Structure of Sso10a, a Hyperthermophile DNA-binding Protein with an Extended Anti-parallel Coiled Coil

• PDB DOI: 10.2210/pdb1XSX/pdb
• BMRB: 5891

• Classification: DNA BINDING PROTEIN
• Organism(s): Saccharolobus solfataricus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2004-10-20 Released: 2005-03-01 
• Deposition Author(s): Kahsai, M.A., Vogler, B., Clark, A.T., Edmondson, S.P., Shriver, J.W.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 75 
• Conformers Submitted: 11 
• Selection Criteria: 10 smallest RMSD out of 13 lowest energy 

Literature

Solution Structure, Stability, and Flexibility of Sso10a: A Hyperthermophile Coiled-Coil DNA-Binding Protein(,).

Kahsai, M.A., Vogler, B., Clark, A.T., Edmondson, S.P., Shriver, J.W.

(2005) Biochemistry 44: 2822-2832

• PubMed: 15723526 
• DOI: 10.1021/bi047669t
• Primary Citation of Related Structures:  
  1XSX


• PubMed Abstract: 
  

Sso10a is one of a number of DNA-binding proteins from the hyperthermophile Sulfolobus solfataricus that has been associated with DNA packaging and chromatin regulation. Sequence analysis indicates that it is a member of a conserved group of archaeal transcription regulators (COG3432). We have determined the solution structure of Sso10a and show that it is a homodimer of winged-helix DNA-binding domains. The dimer interface consists of an extended antiparallel coiled coil, with the globular DNA-binding domains positioned at opposite ends of a solvent-exposed coiled-coil rod. NMR structure refinement of the elongated structure benefited not only from the inclusion of residual dipolar couplings from partially aligned samples but also the influence of anisotropic rotational diffusion on heteronuclear relaxation. An analysis of backbone mobility using (15)N relaxation rates indicated that the overall tertiary and quaternary structure is largely inflexible on the nanosecond to picosecond time scale. Amide hydrogen exchange data demonstrated that the most stable region of the protein extends from the core of the winged helices into the coiled coil. The positions of the globular heads relative to the coiled coil in solution deviate only slightly from that observed in a crystal structure. The most significant difference between the solution and crystal structures occurs in the putative DNA-binding helix-turn-helix (HTH) motif. This is the region of lowest stability in solution and a point of protein-protein contact in the crystal. Alternative conformations of the HTH motif may permit adjustment of the structure for optimal DNA binding.

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Organizational Affiliation: 

Biomolecular Nuclear Magnetic Resonance Laboratory, Department of Chemistry, Graduate Program in Biotechnology Science and Engineering, University of Alabama in Huntsville, Huntsville, Alabama 35899, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Sso10a	A, B	95	Saccharolobus solfataricus	Mutation(s): 0  Gene Names: sso10a
UniProt
Find proteins for Q5W1E8 (Saccharolobus solfataricus) Explore Q5W1E8  Go to UniProtKB:  Q5W1E8

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 75 
• Conformers Submitted: 11 
• Selection Criteria: 10 smallest RMSD out of 13 lowest energy 
• OLDERADO: 1XSX Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2004-10-20 
• Released Date: 2005-03-01 
Deposition Author(s): Kahsai, M.A., Vogler, B., Clark, A.T., Edmondson, S.P., Shriver, J.W.

Revision History  

• Version 1.0: 2005-03-01
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2022-03-02
  Changes: Data collection, Database references, Derived calculations