1AFD

STRUCTURAL BASIS OF GALACTOSE RECOGNITION IN C-TYPE ANIMAL LECTINS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.234 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural basis of galactose recognition by C-type animal lectins.

Kolatkar, A.R.Weis, W.I.

(1996) J.Biol.Chem. 271: 6679-6685

  • Primary Citation of Related Structures:  1AFA, 1AFB

  • PubMed Abstract: 
  • The asialoglycoprotein receptors and many other C-type (Ca2+-dependent) animal lectins specifically recognize galactose- or N-acetylgalactosamine-terminated oligosaccharides. Analogous binding specificity can be engineered into the homologous rat man ...

    The asialoglycoprotein receptors and many other C-type (Ca2+-dependent) animal lectins specifically recognize galactose- or N-acetylgalactosamine-terminated oligosaccharides. Analogous binding specificity can be engineered into the homologous rat mannose-binding protein A by changing three amino acids and inserting a glycine-rich loop (Iobst, S. T., and Drickamer, K. (1994) J. Biol. Chem. 269, 15512-15519). Crystal structures of this mutant complexed with beta-methyl galactoside and N-acetylgalactosamine (GalNAc) reveal that as with wild-type mannose-binding proteins, the 3- and 4-OH groups of the sugar directly coordinate Ca2+ and form hydrogen bonds with amino acids that also serve as Ca2+ ligands. The different stereochemistry of the 3- and 4-OH groups in mannose and galactose, combined with a fixed Ca2+ coordination geometry, leads to different pyranose ring locations in the two cases. The glycine-rich loop provides selectivity against mannose by holding a critical tryptophan in a position optimal for packing with the apolar face of galactose but incompatible with mannose binding. The 2-acetamido substituent of GalNAc is in the vicinity of amino acid positions identified by site-directed mutagenesis (Iobst, S. T., and Drickamer, K. (1996) J. Biol. Chem. 271, 6686-6693) as being important for the formation of a GalNAc-selective binding site.


    Related Citations: 
    • Binding of Sugar Ligands to Ca+2-Dependent Animal Lectins II. Generation of High-Affinity Galactose Binding by Site-Directed Mutagenesis
      Iobst, S.T.,Drickamer, K.
      (1994) J.Biol.Chem. 269: 15512
    • Trimeric Structure of a C-Type Mannose-Binding Protein
      Weis, W.I.,Drickamer, K.
      (1994) Structure 2: 1227


    Organizational Affiliation

    Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MANNOSE-BINDING PROTEIN-A
1, 2, 3
154Rattus norvegicusGene Names: Mbl1
Find proteins for P19999 (Rattus norvegicus)
Go to UniProtKB:  P19999
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
1, 3
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
CA
Query on CA

Download SDF File 
Download CCD File 
1, 2, 3
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.234 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 80.400α = 90.00
b = 84.700β = 105.40
c = 98.000γ = 90.00
Software Package:
Software NamePurpose
X-PLORrefinement
SCALEPACKdata scaling
DENZOdata reduction
X-PLORphasing
X-PLORmodel building

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1996-04-03
    Type: Initial release
  • Version 1.1: 2008-03-03
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance