1QMJ

CG-16, a homodimeric agglutinin from chicken liver


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

The 2.15 A Crystal Structure of Cg-16, the Developmentally Regulated Homodimeric Chicken Galectin

Varela, P.F.Solis, D.Diaz-Maurino, T.Kaltner, H.Gabius, H.-J.Romero, A.

(1999) J.Mol.Biol. 294: 537

  • DOI: 10.1006/jmbi.1999.3273

  • PubMed Abstract: 
  • Differential developmental regulation of expression, fine-specificity differences in ligand recognition and disparate capacity for homodimerization are characteristics of the two currently known proto-type chicken galectins. The X-ray crystal structu ...

    Differential developmental regulation of expression, fine-specificity differences in ligand recognition and disparate capacity for homodimerization are characteristics of the two currently known proto-type chicken galectins. The X-ray crystal structure of the first avian galectin, the homodimeric agglutinin from chicken liver (CG-16), has been solved in the absence of ligand in two crystal forms. Although the arrangement of lectin dimers in the two crystals is different, the structure of the monomers and their association into the extended beta-sandwich that characterises the dimer are virtually identical. The fold establishes a beta-sandwich motif composed of a five-stranded and a six-stranded beta-sheet evocative of proto-type mammalian galectins. The carbohydrate-binding site is occupied by six water molecules that take the place of the sugar in the complex. They help to stabilise in the absence of the ligand the spatial arrangement of the amino acid side-chains involved in sugar recognition. Docking of N-acetyllactosamine into the binding site reveals that three of these water molecules, which are in direct contact with the protein, occupy positions equivalent to the key sugar hydroxyl groups, namely the hydroxyls at positions 4 and 6 of the galactose unit and at position 3 of the N-acetylglucosamine unit. Crystallographic data are fully consistent with the binding features in solution previously derived from chemical mapping with deoxy, fluoro and O-methyl derivatives and laser photo-CIDNP (chemically induced dynamic nuclear polarisation) studies. The possible molecular basis for the monomeric character of the chicken intestinal galectin as well as potential mechanisms of oxidative inactivation by disulphide bridging are evaluated on the basis of the given structural information concerning the CG-16 dimer interface and the cysteine residues, respectively.


    Related Citations: 
    • Developmentally Regulated Lectin in Embryonic Chick Muscle and a Myogenic Cell Line
      Nowak, T.P.,Haywood, P.L.,Barondes, S.H.
      (1976) Biochem.Biophys.Res.Commun. 68: 650


    Organizational Affiliation

    Centro de Investigaciones Biológicas, CSIC, Velázquez 144, Madrid, E-28006, Spain.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
BETA-GALACTOSIDE-BINDING LECTIN
A, B
132Gallus gallusMutation(s): 0 
Find proteins for P23668 (Gallus gallus)
Go to UniProtKB:  P23668
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
BME
Query on BME

Download SDF File 
Download CCD File 
A, B
BETA-MERCAPTOETHANOL
C2 H6 O S
DGVVWUTYPXICAM-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.185 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 71.380α = 90.00
b = 82.600β = 90.00
c = 112.760γ = 90.00
Software Package:
Software NamePurpose
X-PLORrefinement
SCALAdata scaling
MOSFLMdata reduction
X-PLORphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-02-06
    Type: Initial release
  • Version 1.1: 2012-02-22
    Type: Database references, Derived calculations, Non-polymer description, Other, Structure summary, Version format compliance
  • Version 1.2: 2017-07-05
    Type: Data collection
  • Version 1.3: 2019-05-08
    Type: Data collection, Derived calculations, Experimental preparation