1PHO

CRYSTAL STRUCTURES EXPLAIN FUNCTIONAL PROPERTIES OF TWO E. COLI PORINS

• PDB DOI: https://doi.org/10.2210/pdb1PHO/pdb

• Classification: OUTER MEMBRANE PROTEIN
• Organism(s): Escherichia coli
• Mutation(s): No 
• Membrane Protein: Yes  OPMPDBTMMemProtMDmpstruc


• Deposited: 1993-01-15 Released: 1993-10-31 
• Deposition Author(s): Schirmer, T., Cowan, S.W., Jansonius, J.N.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Work: 
  0.222 (Depositor) 
• R-Value Observed: 
  0.222 (Depositor) 

Literature

Crystal structures explain functional properties of two E. coli porins.

Cowan, S.W., Schirmer, T., Rummel, G., Steiert, M., Ghosh, R., Pauptit, R.A., Jansonius, J.N., Rosenbusch, J.P.

(1992) Nature 358: 727-733

• PubMed: 1380671 
• DOI: https://doi.org/10.1038/358727a0
• Primary Citation of Related Structures:  
  1PHO


• PubMed Abstract: 
  

  Porins form aqueous channels that aid the diffusion of small hydrophilic molecules across the outer membrane of Gram-negative bacteria. The crystal structures of matrix porin and phosphoporin both reveal trimers of identical subunits, each subunit consisting of a 16-stranded anti-parallel beta-barrel containing a pore. A long loop inside the barrel contributes to a constriction of the channel where the charge distribution affects ion selectivity. The structures explain at the molecular level functional characteristics and their alterations by known mutations.

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Organizational Affiliation: 

Department of Structural Biology, University of Basel, Switzerland.

Biological Assembly 1  

Global Symmetry: Cyclic - C3  (Explore in 3D)
Global Stoichiometry: Homo 3-mer - A3 

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

Macromolecule Content

• Total Structure Weight: 36.87 kDa 
• Atom Count: 2,602 
• Modelled Residue Count: 330 
• Deposited Residue Count: 330 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PHOSPHOPORIN	A	330	Escherichia coli	Mutation(s): 0  Membrane Entity: Yes
UniProt
Find proteins for P02932 (Escherichia coli (strain K12)) Explore P02932  Go to UniProtKB:  P02932

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Work:  0.222 (Depositor) 
• R-Value Observed: 0.222 (Depositor) 

Space Group: P 3 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 119.9	α = 90
b = 119.9	β = 90
c = 51.9	γ = 120

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1993-10-31 
Deposition Author(s): Schirmer, T., Cowan, S.W., Jansonius, J.N.

Revision History  

• Version 1.0: 1993-10-31
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance
• Version 1.3: 2024-02-14
  Changes: Data collection, Database references, Other