1MPR

MALTOPORIN FROM SALMONELLA TYPHIMURIUM

• PDB DOI: https://doi.org/10.2210/pdb1MPR/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Salmonella enterica subsp. enterica serovar Typhimurium
• Mutation(s): No 
• Membrane Protein: Yes  PDBTMMemProtMD


• Deposited: 1996-12-18 Released: 1997-03-12 
• Deposition Author(s): Meyer, J.E.W., Schulz, G.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.80 Å
• R-Value Free: 0.211 
• R-Value Work: 0.183 
• R-Value Observed: 0.183 

Literature

Structure of maltoporin from Salmonella typhimurium ligated with a nitrophenyl-maltotrioside.

Meyer, J.E., Hofnung, M., Schulz, G.E.

(1997) J Mol Biol 266: 761-775

• PubMed: 9102468 
• DOI: https://doi.org/10.1006/jmbi.1996.0823
• Primary Citation of Related Structures:  
  1MPR, 2MPR


• PubMed Abstract: 
  

  The maltodextrin-specific (malto-)porin from Salmonella typhimurium has been crystallized. Its three-dimensional structure was determined at 2.4 A resolution (1 A = 0.1 nm). A comparison with the structure of the homologous porin from Escherichia coli as well as with the sequences of other related porins showed that there are regions of appreciable sequence and structure variability, despite close overall similarity. The maltoporin structure was analyzed with a bound nitrophenyl-maltotrioside as well as without ligand. Maltotrioside binding had a negligible effect on the polypeptide structure. It binds at the pore eyelet assuming a conformation close to the natural amylose helix.

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Organizational Affiliation: 

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

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 (software)

Macromolecule Content

• Total Structure Weight: 144.23 kDa 
• Atom Count: 10,513 
• Modelled Residue Count: 1,263 
• Deposited Residue Count: 1,281 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
MALTOPORIN	A, B, C	427	Salmonella enterica subsp. enterica serovar Typhimurium	Mutation(s): 0  Membrane Entity: Yes
UniProt
Find proteins for P26466 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)) Explore P26466  Go to UniProtKB:  P26466

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	D [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.80 Å
• R-Value Free: 0.211 
• R-Value Work: 0.183 
• R-Value Observed: 0.183 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 124.5	α = 90
b = 211.8	β = 90
c = 184.3	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
AMoRE	phasing
RAVE	model building
X-PLOR	model building
X-PLOR	refinement
RAVE	phasing
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1997-03-12 
Deposition Author(s): Meyer, J.E.W., Schulz, G.E.

Revision History  

• Version 1.0: 1997-03-12
  Type: Initial release
  
• Version 1.1: 2008-03-03
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2023-08-09
  Changes: Data collection, Database references, Derived calculations, Refinement description