Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 31.67 kDa 
• Atom Count: 2381 
• Modelled Residue Count: 289 
• Deposited Residue Count: 289 
• Unique protein chains: 1

3PRN

E1M, A104W MUTANT OF RH. BLASTICA PORIN

• DOI: 10.2210/pdb3PRN/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Rhodobacter blasticus
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 1998-06-12 Released: 1998-08-12 
• Deposition Author(s): Maveyraud, L., Schmid, B., Schulz, G.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.190 
• R-Value Work: 0.169 

Literature

Porin mutants with new channel properties.

Schmid, B., Maveyraud, L., Kromer, M., Schulz, G.E.

(1998) Protein Sci 7: 1603-1611

• PubMed: 9684893 
• DOI: 10.1002/pro.5560070714
• Primary Citation of Related Structures:  
  2PRN, 1BH3, 8PRN, 7PRN, 6PRN, 5PRN, 3PRN


• PubMed Abstract: 
  

The general diffusion porin from Rhodopseudomonas blastica was produced in large amounts in Escherichia coli inclusion bodies and (re)natured to the exact native structure. Here, we report on 13 mutants at the pore eyelet giving rise to new diffusion properties as measured in planar lipid bilayer experiments. The crystal structures of seven of these mutants were established. The effects of charge-modifying mutations at the pore eyelet are consistent with the known selectivity for cations. Deletions of 16 and 27 residues of the constriction loop L3 resulted in labile trimers and pores. The reduction of the eyelet cross section by introducing tryptophans gave rise to a closely correlated decrease of the conductivities. A mutant with six newly introduced tryptophans in the eyelet closed its pore in a defined manner within seconds under a voltage of 20 mV, suggesting the existence of two states. The results indicate that the pore can be engineered in a rational manner.

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Related Citations: 

• Expression of Porin from Rhodopseudomonas Blastica in Escherichia Coli Inclusion Bodies and Folding Into Exact Native Structure
  Schmid, B., Kromer, M., Schulz, G.E.
  (1996) FEBS Lett 381: 111

• Refined Structure of the Porin from Rhodopseudomonas Blastica. Comparison with the Porin from Rhodobacter Capsulatus
  Kreusch, A., Schulz, G.E.
  (1994) J Mol Biol 243: 891

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Organizational Affiliation: 

Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, Freiburg im Breisgau, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PORIN	A	289	Rhodobacter blasticus	Mutation(s): 1  Gene Names: opmA
Membrane protein Mpstruc	Group:  TRANSMEMBRANE PROTEINS: BETA-BARREL		Sub Group:  Beta-Barrel Membrane Proteins: Porins and Relatives	Protein:  Porin, E1M/A116K Mutant
Find proteins for P39767 (Rhodobacter blasticus) Explore P39767  Go to UniProtKB:  P39767

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
C8E	C [auth A], D [auth A], E [auth A]	(HYDROXYETHYLOXY)TRI(ETHYLOXY)OCTANE C16 H34 O5 FEOZZFHAVXYAMB-UHFFFAOYSA-N
MG	B [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.190 
• R-Value Work: 0.169 
• Space Group: H 3

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 104.82	α = 90
b = 104.82	β = 90
c = 124.36	γ = 120

Software Package:

Software Name	Purpose
CCP4	model building
REFMAC	refinement
XDS	data reduction
XSCALE	data scaling
CCP4	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1998-06-12 
• Released Date: 1998-08-12 
Deposition Author(s): Maveyraud, L., Schmid, B., Schulz, G.E.

Revision History  

• Version 1.0: 1998-08-12
  Type: Initial release
  
• Version 1.1: 2008-03-03
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance