Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 40.72 kDa 
• Atom Count: 3130 
• Residue Count: 370 
• Unique protein chains: 1

1MPB

MALTODEXTRIN-BINDING PROTEIN (MALTOSE-BINDING PROTEIN) MUTANT, WITH ARGININE REPLACING TRYPTOPHAN AT POSITION 230 (TRP-230-ARG)

• DOI: 10.2210/pdb1MPB/pdb

• Classification: PERIPLASMIC BINDING PROTEIN
• Organism(s): Escherichia coli K-12
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1995-07-25 Released: 1995-10-15 
• Deposition Author(s): Shilton, B.H., Mowbray, S.L.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Work: 0.182 
• R-Value Observed: 0.182 

Literature

Crystal Structures and Solution Conformations of a Dominant-Negative Mutant of Escherichia Coli Maltose-Binding Protein

Shilton, B.H., Shuman, H.A., Mowbray, S.L.

(1996) J Mol Biol 264: 364-376

• PubMed: 8951382 
• DOI: 10.1006/jmbi.1996.0646
• Structures With Same Primary Citation


• PubMed Abstract: 
  

A mutant of the periplasmic maltose-binding protein (MBP) with altered transport properties was studied. A change of residue 230 from tryptophan to arginine results in dominant-negative MBP: expression of this protein against a wild-type background causes inhibition of maltose transport. As part of an investigation of the mechanism of such inhibition, we have solved crystal structures of both unliganded and liganded mutant protein. In the closed, liganded conformation, the side-chain of R230 projects into a region of the surface of MBP that has been identified as important for transport while in the open form, the same side-chain takes on a different, and less ordered, conformation. The crystallographic work is supplemented with a small-angle X-ray scattering study that provides evidence that the solution conformation of unliganded mutant is similar to that of wild-type MBP. It is concluded that dominant-negative inhibition of maltose transport must result from the formation of a non-productive complex between liganded-bound mutant MBP and wild-type MalFGK2. A general kinetic framework for transport by either wild-type MalFGK2 or MBP-independent MalFGK2 is used to understand the effects of dominant-negative MBP molecules on both of these systems.

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Organizational Affiliation: 

Department of Molecular Biology, Swedish Agricultural University, Uppsala, Sweden.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
MALTODEXTRIN-BINDING PROTEIN	A	370	Escherichia coli K-12	Mutation(s): 0  Gene Names: malE, b4034, JW3994
Find proteins for P0AEX9 (Escherichia coli (strain K12)) Go to UniProtKB:  P0AEX9

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Work: 0.182 
• R-Value Observed: 0.182 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 44.52	α = 90
b = 82.89	β = 101.57
c = 58.22	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
DENZO	data reduction
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1995-07-25 
• Released Date: 1995-10-15 
Deposition Author(s): Shilton, B.H., Mowbray, S.L.

Revision History 

• Version 1.0: 1995-10-15
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Source and taxonomy, Version format compliance