3DEM

CUB1-EGF-CUB2 domain of HUMAN MASP-1/3


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.245 
  • R-Value Work: 0.222 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of the CUB1-EGF-CUB2 domain of human MASP-1/3 and identification of its interaction sites with mannan-binding lectin and ficolins

Teillet, F.Gaboriaud, C.Lacroix, M.Martin, L.Arlaud, G.J.Thielens, N.M.

(2008) J.Biol.Chem. 283: 25715-25724

  • DOI: 10.1074/jbc.M803551200

  • PubMed Abstract: 
  • MASP-1 and MASP-3 are homologous proteases arising from alternative splicing of the MASP1/3 gene. They include an identical CUB(1)-EGF-CUB(2)-CCP(1)-CCP(2) module array prolonged by different serine protease domains at the C-terminal end. The x-ray s ...

    MASP-1 and MASP-3 are homologous proteases arising from alternative splicing of the MASP1/3 gene. They include an identical CUB(1)-EGF-CUB(2)-CCP(1)-CCP(2) module array prolonged by different serine protease domains at the C-terminal end. The x-ray structure of the CUB(1)-EGF-CUB(2) domain of human MASP-1/3, responsible for interaction of MASP-1 and -3 with their partner proteins mannan-binding lectin (MBL) and ficolins, was solved to a resolution of 2.3A(.) The structure shows a head-to-tail homodimer mainly stabilized by hydrophobic interactions between the CUB(1) module of one monomer and the epidermal growth factor (EGF) module of its counterpart. A Ca(2+) ion bound primarily to both EGF modules stabilizes the intra- and inter-monomer CUB(1)-EGF interfaces. Additional Ca(2+) ions are bound to each CUB(1) and CUB(2) module through six ligands contributed by Glu(49), Asp(57), Asp(102), and Ser(104) (CUB(1)) and their counterparts Glu(216), Asp(226), Asp(263), and Ser(265) (CUB(2)), plus one and two water molecules, respectively. To identify the residues involved in interaction of MASP-1 and -3 with MBL and L- and H-ficolins, 27 point mutants of human MASP-3 were generated, and their binding properties were analyzed using surface plasmon resonance spectroscopy. These mutations map two homologous binding sites contributed by modules CUB(1) and CUB(2), located in close vicinity of their Ca(2+)-binding sites and stabilized by the Ca(2+) ion. This information allows us to propose a model of the MBL-MASP-1/3 interaction, involving a major electrostatic interaction between two acidic Ca(2+) ligands of MASP-1/3 and a conserved lysine of MBL. Based on these and other data, a schematic model of a MBL.MASP complex is proposed.


    Organizational Affiliation

    Laboratoire d'Enzymologie Mol├ęculaire, Institut de Biologie Structurale Jean-Pierre Ebel, CNRS-CEA-UJF, UMR 5975, 41 Rue Jules Horowitz, Grenoble Cedex 1, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Complement factor MASP-3
A, B
278Homo sapiensMutation(s): 0 
Gene Names: MASP1 (CRARF, CRARF1, PRSS5)
EC: 3.4.21.-
Find proteins for P48740 (Homo sapiens)
Go to Gene View: MASP1
Go to UniProtKB:  P48740
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A, B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.245 
  • R-Value Work: 0.222 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 88.692α = 90.00
b = 110.232β = 90.00
c = 190.587γ = 90.00
Software Package:
Software NamePurpose
AMoREphasing
XSCALEdata scaling
XDSdata reduction
REFMACrefinement
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2008-06-10 
  • Released Date: 2008-07-01 
  • Deposition Author(s): Gaboriaud, C.

Revision History 

  • Version 1.0: 2008-07-01
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Non-polymer description, Version format compliance
  • Version 1.2: 2015-05-20
    Type: Database references