3AYE

Crystal structure of galectin-3 CRD domian complexed with lactose


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.175 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Structural basis for distinct binding properties of the human galectins to thomsen-friedenreich antigen

Bian, C.F.Zhang, Y.Sun, H.Li, D.F.Wang, D.C.

(2011) Plos One 6: e25007-e25007

  • DOI: 10.1371/journal.pone.0025007
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The Thomsen-Friedenreich (TF or T) antigen, Galβ1-3GalNAcα1-O-Ser/Thr, is the core 1 structure of O-linked mucin type glycans appearing in tumor-associated glycosylation. The TF antigen occurs in about 90% of human cancer cells and is a potential lig ...

    The Thomsen-Friedenreich (TF or T) antigen, Galβ1-3GalNAcα1-O-Ser/Thr, is the core 1 structure of O-linked mucin type glycans appearing in tumor-associated glycosylation. The TF antigen occurs in about 90% of human cancer cells and is a potential ligand for the human endogenous galectins. It has been reported that human galectin-1 (Gal-1) and galectin-3 (Gal-3) can perform their cancer-related functions via specifically recognizing TF antigen. However, the detailed binding properties have not been clarified and structurally characterized. In this work, first we identified the distinct TF-binding abilities of Gal-1 and Gal-3. The affinity to TF antigen for Gal-3 is two orders of magnitude higher than that for Gal-1. The structures of Gal-3 carbohydrate recognition domain (CRD) complexed with TF antigen and derivatives, TFN and GM1, were then determined. These structures show a unique Glu-water-Arg-water motif-based mode as previously observed in the mushroom galectin AAL. The observation demonstrates that this recognition mode is commonly adopted by TF-binding galectins, either as endogenous or exogenous ones. The detailed structural comparisons between Gal-1 and Gal-3 CRD and mutagenesis experiments reveal that a pentad residue motif ((51)AHGDA(55)) at the loop (g1-L4) connecting β-strands 4 and 5 of Gal-1 produces a serious steric hindrance for TF binding. This motif is the main structural basis for Gal-1 with the low affinity to TF antigen. These findings provide the intrinsic structural elements for regulating the TF-binding activity of Gal-1 in some special conditions and also show certain target and approach for mediating some tumor-related bioactivities of human galectins.


    Organizational Affiliation

    National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, People's Republic of China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Galectin-3
A, B
135Homo sapiensMutation(s): 0 
Gene Names: LGALS3 (MAC2)
Find proteins for P17931 (Homo sapiens)
Go to Gene View: LGALS3
Go to UniProtKB:  P17931
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
LAT
Query on LAT

Download SDF File 
Download CCD File 
A, B
BETA-LACTOSE
C12 H22 O11
GUBGYTABKSRVRQ-DCSYEGIMSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
LATIC50: 800000 nM (99) BINDINGDB
LATKd: 93 - 230000 nM (99) BINDINGDB
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.175 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 32.640α = 64.37
b = 51.670β = 86.25
c = 60.100γ = 80.47
Software Package:
Software NamePurpose
SCALAdata scaling
CrystalCleardata collection
PHASESphasing
CNSrefinement
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-10-12
    Type: Initial release