1EZ9

STRUCTURE OF MALTOTETRAITOL BOUND TO OPEN-FORM MALTODEXTRIN BINDING PROTEIN IN P1 CRYSTAL FORM


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.192 

wwPDB Validation 3D Report Full Report



Literature

Structural evidence for a dominant role of nonpolar interactions in the binding of a transport/chemosensory receptor to its highly polar ligands.

Duan, X.Quiocho, F.A.

(2002) Biochemistry 41: 706-712

  • DOI: 10.1021/bi015784n
  • Primary Citation of Related Structures:  
    1EZ9, 1JW5, 1JW4

  • PubMed Abstract: 
  • The receptor, a maltose/maltooligosaccharide-binding protein, has been found to be an excellent system for the study of molecular recognition because its polar and nonpolar binding functions are segregated into two globular domains. The X-ray structu ...

    The receptor, a maltose/maltooligosaccharide-binding protein, has been found to be an excellent system for the study of molecular recognition because its polar and nonpolar binding functions are segregated into two globular domains. The X-ray structures of the "closed" and "open" forms of the protein complexed with maltose and maltotetraitol have been determined. These sugars have approximately 3 times more accessible polar surface (from OH groups) than nonpolar surface (from small clusters of sugar ring CH bonds). In the closed structures, the oligosaccharides are buried in the groove between the two domains of the protein and bound by extensive hydrogen bonding interactions of the OH groups with the polar residues confined mostly in one domain and by nonpolar interactions of the CH clusters with four aromatic residues lodged in the other domain. Substantial contacts between the sugar hydroxyls and aromatic residues are also formed. In the open structures, the oligosaccharides are bound almost exclusively in the domain rich in aromatic residues. This finding, along with the analysis of buried surface area due to complex formations in the open and closed structures, supports a major role for nonpolar interactions in initial ligand binding even when the ligands have significantly greater potential for highly specific polar interactions.


    Organizational Affiliation

    Howard Hughes Medical Institute and Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
MALTOSE-BINDING PERIPLASMIC PROTEINAB370Escherichia coli K-12Mutation(s): 0 
Gene Names: malEb4034JW3994
Find proteins for P0AEX9 (Escherichia coli (strain K12))
Explore P0AEX9 
Go to UniProtKB:  P0AEX9
Protein Feature View
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  • Reference Sequence
Oligosaccharides

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Entity ID: 2
MoleculeChainsChain Length2D Diagram Glycosylation
alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose-(1-4)-D-glucose
C, D
4 N/A
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.192 
  • Space Group: P 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 51.745α = 89.31
b = 57.9β = 81.78
c = 64.594γ = 71.97
Software Package:
Software NamePurpose
X-PLORmodel building
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
X-PLORphasing

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-01-30
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Source and taxonomy, Version format compliance
  • Version 1.3: 2018-05-02
    Changes: Data collection
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Structure summary