3N35

Erythrina corallodendron lectin mutant (Y106G) with N-Acetylgalactosamine


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.189 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.177 

wwPDB Validation   3D Report Full Report


This is version 2.0 of the entry. See complete history


Literature

Modification of the sugar specificity of a plant lectin: structural studies on a point mutant of Erythrina corallodendron lectin.

Thamotharan, S.Karthikeyan, T.Kulkarni, K.A.Shetty, K.N.Surolia, A.Vijayan, M.Suguna, K.

(2011) Acta Crystallogr D Biol Crystallogr 67: 218-227

  • DOI: 10.1107/S0907444911004525
  • Primary Citation of Related Structures:  
    3N35, 3N36, 3N3H

  • PubMed Abstract: 
  • A mutant of Erythrina corallodendron lectin was generated with the aim of enhancing its affinity for N-acetylgalactosamine. A tyrosine residue close to the binding site of the lectin was mutated to a glycine in order to facilitate stronger interactions between the acetamido group of the sugar and the lectin which were prevented by the side chain of the tyrosine in the wild-type lectin ...

    A mutant of Erythrina corallodendron lectin was generated with the aim of enhancing its affinity for N-acetylgalactosamine. A tyrosine residue close to the binding site of the lectin was mutated to a glycine in order to facilitate stronger interactions between the acetamido group of the sugar and the lectin which were prevented by the side chain of the tyrosine in the wild-type lectin. The crystal structures of this Y106G mutant lectin in complex with galactose and N-acetylgalactosamine have been determined. A structural rationale has been provided for the differences in the relative binding affinities of the wild-type and mutant lectins towards the two sugars based on the structures. A hydrogen bond between the O6 atom of the sugars and the variable loop of the carbohydrate-binding site of the lectin is lost in the mutant complexes owing to a conformational change in the loop. This loss is compensated by an additional hydrogen bond that is formed between the acetamido group of the sugar and the mutant lectin in the complex with N-acetylgalactosamine, resulting in a higher affinity of the mutant lectin for N-acetylgalactosamine compared with that for galactose, in contrast to the almost equal affinity of the wild-type lectin for the two sugars. The structure of a complex of the mutant with a citrate ion bound at the carbohydrate-binding site that was obtained while attempting to crystallize the complexes with sugars is also presented.


    Organizational Affiliation

    Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Lectin A242Erythrina corallodendronMutation(s): 1 
Find proteins for P16404 (Erythrina corallodendron)
Explore P16404 
Go to UniProtKB:  P16404
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
A2G
Query on A2G

Download Ideal Coordinates CCD File 
A
2-acetamido-2-deoxy-alpha-D-galactopyranose
C8 H15 N O6
OVRNDRQMDRJTHS-CBQIKETKSA-N
 Ligand Interaction
MN
Query on MN

Download Ideal Coordinates CCD File 
A
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

Download Ideal Coordinates CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
A2GKd :  431000   nM  PDBBind
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.189 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.177 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 102.514α = 90
b = 102.514β = 90
c = 57.023γ = 120
Software Package:
Software NamePurpose
MAR345dtbdata collection
PHASERphasing
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2011-03-30
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Database references, Derived calculations, Structure summary