4AQB

MBL-Ficolin Associated Protein-1, MAP-1 aka MAP44


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.2 Å
  • R-Value Free: 0.301 
  • R-Value Work: 0.279 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Crystal Structure and Functional Characterization of the Complement Regulator Mannose-Binding Lectin (Mbl)/Ficolin-Associated Protein-1 (Map-1).

Skjoedt, M.O.Roversi, P.Hummelshoj, T.Palarasah, Y.Rosbjerg, A.Johnson, S.Lea, S.M.Garred, P.

(2012) J.Biol.Chem. 287: 32913

  • DOI: 10.1074/jbc.M112.386680

  • PubMed Abstract: 
  • The human lectin complement pathway activation molecules comprise mannose-binding lectin (MBL) and ficolin-1, -2, and -3 in complex with associated serine proteases MASP-1, -2, and -3 and the non-enzymatic small MBL associated protein or sMAP. Recent ...

    The human lectin complement pathway activation molecules comprise mannose-binding lectin (MBL) and ficolin-1, -2, and -3 in complex with associated serine proteases MASP-1, -2, and -3 and the non-enzymatic small MBL associated protein or sMAP. Recently, a novel plasma protein named MBL/ficolin-associated protein-1 (MAP-1) was identified in humans. This protein is the result of a differential splicing of the MASP1 gene and includes the major part of the heavy chain but lacks the serine protease domain. We investigated the direct interactions of MAP-1 and MASP-3 with ficolin-3 and MBL using surface plasmon resonance and found affinities around 5 nm and 2.5 nm, respectively. We studied structural aspects of MAP-1 and could show by multi-angle laser light scattering that MAP-1 forms a calcium-dependent homodimer in solution. We were able to determine the crystal structure of MAP-1, which also contains a head-to-tail dimer ∼146 Å long. This structure of MAP-1 also enables modeling and assembly of the MASP-1 molecule in its entirety. Finally we found that MAP-1 competes with all three MASPs for ligand binding and is able to mediate a strong dose-dependent inhibitory effect on the lectin pathway activation, as measured by levels of C3 and C9.


    Organizational Affiliation

    Laboratory of Molecular Medicine, Department of Clinical Immunology, Rigshospitalet, Faculty of Health Sciences, University of Copenhagen, DK 2100 Copenhagen, Denmark. moskjoedt@gmail.com




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MANNAN-BINDING LECTIN SERINE PROTEASE 1
A
361Homo 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 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

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

Download SDF File 
Download CCD File 
A
ALPHA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-PQMKYFCFSA-N
 Ligand Interaction
BMA
Query on BMA

Download SDF File 
Download CCD File 
A
BETA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-RWOPYEJCSA-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: 4.2 Å
  • R-Value Free: 0.301 
  • R-Value Work: 0.279 
  • Space Group: P 43 2 2
Unit Cell:
Length (Å)Angle (°)
a = 94.150α = 90.00
b = 94.150β = 90.00
c = 242.570γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
XDSdata reduction
BUSTERrefinement
XSCALEdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-08-08
    Type: Initial release
  • Version 1.1: 2012-10-03
    Type: Database references