Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Dihedral - D2  (3D View)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 50.54 kDa 
• Atom Count: 2808 
• Residue Count: 394 
• Unique protein chains: 1

1SRU

Crystal structure of full length E. coli SSB protein

• DOI: 10.2210/pdb1SRU/pdb

• Classification: REPLICATION
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2004-03-23 Released: 2004-08-03 
• Deposition Author(s): Savvides, S.N., Raghunathan, S., Fuetterer, K., Kozlov, A.G., Lohman, T.M., Waksman, G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.30 Å
• R-Value Free: 0.309 
• R-Value Work: 0.288 
• R-Value Observed: 0.288 

Literature

The C-terminal domain of full-length E. coli SSB is disordered even when bound to DNA.

Savvides, S.N., Raghunathan, S., Fuetterer, K., Kozlov, A.G., Lohman, T.M., Waksman, G.

(2004) Protein Sci 13: 1942-1947

• PubMed: 15169953 
• DOI: 10.1110/ps.04661904
• Primary Citation of Related Structures:  
  1SRU


• PubMed Abstract: 
  

The crystal structure of full-length homotetrameric single-stranded DNA (ssDNA)-binding protein from Escherichia coli (SSB) has been determined to 3.3 A resolution and reveals that the entire C-terminal domain is disordered even in the presence of ssDNA. To our knowledge, this is the first experimental evidence that the C-terminal domain of SSB may be inherently disordered. The N-terminal DNA-binding domain of the protein is well ordered and is virtually indistinguishable from the previously determined structure of the chymotryptic fragment of SSB (SSBc) in complex with ssDNA. The absence of observable interactions with the core protein and the crystal packing of SSB together suggest that the disordered C-terminal domains likely extend laterally away from the DNA- binding domains, which may facilitate interactions with components of the replication machinery in vivo. The structure also reveals the conservation of molecular contacts between successive tetramers mediated by the L(45) loops as seen in two other crystal forms of SSBc, suggesting a possible functional relevance of this interaction.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Single-strand binding protein	A, B, C, D	113	Escherichia coli	Mutation(s): 0  Gene Names: ssb, exrB, lexC, b4059, C5049, Z5658, ECS5041, SF4145, S3584
Find proteins for P0AGE0 (Escherichia coli (strain K12)) Explore P0AGE0  Go to UniProtKB:  P0AGE0

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.30 Å
• R-Value Free: 0.309 
• R-Value Work: 0.288 
• R-Value Observed: 0.288 
• Space Group: P 3₁ 1 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 60.85	α = 90
b = 60.85	β = 90
c = 348.92	γ = 120

Software Package:

Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2004-03-23 
• Released Date: 2004-08-03 
Deposition Author(s): Savvides, S.N., Raghunathan, S., Fuetterer, K., Kozlov, A.G., Lohman, T.M., Waksman, G.

Revision History 

• Version 1.0: 2004-08-03
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance