2X26 | pdb_00002x26

Crystal structure of the periplasmic aliphatic sulphonate binding protein SsuA from Escherichia coli

• PDB DOI: https://doi.org/10.2210/pdb2X26/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Escherichia coli K-12
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2010-01-11 Released: 2010-04-14 
• Deposition Author(s): Beale, J., Lee, S., Iwata, S., Beis, K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.75 Å
• R-Value Free: 
  0.225 (Depositor), 0.248 (DCC) 
• R-Value Work: 
  0.186 (Depositor), 0.212 (DCC) 
• R-Value Observed: 
  0.188 (Depositor) 

Starting Model: experimental

Literature

Structure of the Aliphatic Sulfonate-Binding Protein Ssua from Escherichia Coli

Beale, J., Lee, S.Y., Iwata, S., Beis, K.

(2010) Acta Crystallogr Sect F Struct Biol Cryst Commun 66: 391

• PubMed: 20383006 
• DOI: https://doi.org/10.1107/S1744309110006226
• Primary Citation Related Structures: 
  2X26


• PubMed Abstract: 
  

  Sulfur is an essential component for the biosynthesis of the sulfur-containing amino acids L-methionine and L-cysteine. Under sulfur-starvation conditions, bacteria are capable of scavenging sulfur from sulfur-containing compounds and transporting it across membranes. Here, the crystal structure of the periplasmic aliphatic sulfonate-binding protein SsuA from Escherichia coli is reported at 1.75 A resolution in the substrate-free state. The overall structure of SsuA resembles the structures of other periplasmic binding proteins and contains two globular domains that form a cleft. Comparison with other periplasmic binding proteins revealed that one of the domains has been displaced by a rigid movement of 17 degrees . Interestingly, the tight crystal packing appears to be mediated by a 13-amino-acid tail from the cloning that folds within the cleft of the next monomer.

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Organizational Affiliation: 
• Membrane Protein Laboratory, Diamond Light Source, Harwell Science and Innovation Campus, Oxfordshire OX11 0DE, England.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 67.65 kDa 
• Atom Count: 5,274 
• Modeled Residue Count: 599 
• Deposited Residue Count: 616 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PERIPLASMIC ALIPHATIC SULPHONATES-BINDING PROTEIN	A, B	308	Escherichia coli K-12	Mutation(s): 0
UniProt
Find proteins for P75853 (Escherichia coli (strain K12)) Explore P75853  Go to UniProtKB:  P75853

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GOL	C [auth A], D [auth B]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.75 Å
• R-Value Free:  0.225 (Depositor), 0.248 (DCC) 
• R-Value Work:  0.186 (Depositor), 0.212 (DCC) 
• R-Value Observed: 0.188 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 40.891	α = 90
b = 96.026	β = 90
c = 142.401	γ = 90

Software Package:

Software Name	Purpose
XDS	data reduction
SCALA	data scaling
BALBES	phasing
MOLREP	phasing
REFMAC	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 2010-04-14 
Deposition Author(s): Beale, J., Lee, S., Iwata, S., Beis, K.

Revision History  

• Version 1.0: 2010-04-14
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Advisory, Version format compliance
• Version 1.2: 2019-03-06
  Changes: Data collection, Experimental preparation, Other
• Version 1.3: 2023-12-20
  Changes: Data collection, Database references, Derived calculations, Other, Refinement description