1EDY

CRYSTAL STRUCTURE OF RAT ALPHA 1-MACROGLOBULIN RECEPTOR BINDING DOMAIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.228 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of a rat alpha 1-macroglobulin receptor-binding domain dimer.

Xiao, T.DeCamp, D.L.Spran, S.R.

(2000) Protein Sci. 9: 1889-1897

  • DOI: 10.1110/ps.9.10.1889

  • PubMed Abstract: 
  • Alpha-macroglobulin inhibits a broad spectrum of proteinases by forming macromolecular cages inside which proteinases are cross-linked and trapped. Upon formation of a complex with proteinase, alpha-macroglobulin undergoes a large conformational chan ...

    Alpha-macroglobulin inhibits a broad spectrum of proteinases by forming macromolecular cages inside which proteinases are cross-linked and trapped. Upon formation of a complex with proteinase, alpha-macroglobulin undergoes a large conformational change that results in the exposure of its receptor-binding domain (RBD). Engagement of this domain by alpha-macroglobulin receptor permits clearance of the alpha-macroglobulin: proteinase complex from circulation. The crystal structure of rat alpha1-macroglobulin RBD has been determined at 2.3 A resolution. The RBD is composed of a nine-stranded beta-sandwich and a single alpha-helix that has been implicated as part of the receptor binding site and that lies on the surface of the beta-sandwich. The crystallographic asymmetric unit contains a dimer of RBDs related by approximate twofold symmetry such that the putative receptor recognition sites of the two monomers are contiguous. By gel filtration and ultracentrifugation, it is shown that RBD dimers form in solution with a dissociation constant of approximately 50 microM. The structure of the RBD dimer might mimic a conformation of transformed alpha-macroglobulin in which the proposed receptor binding residues are exposed on one face of the dimer. A pair of phenylalanine residues replaces a cystine that is conserved in other members of the macroglobulin family. These residues participate in a network of aromatic side-chain interactions that appears to stabilize the dimer interface.


    Organizational Affiliation

    Department of Biochemistry, The University of Texas Southwestern Medical Center, Dallas 75390, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ALPHA 1-MACROGLOBULIN
A, B
134Rattus norvegicusGene Names: A1m (Pzp)
Find proteins for Q63041 (Rattus norvegicus)
Go to UniProtKB:  Q63041
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.228 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 64.377α = 90.00
b = 36.151β = 105.88
c = 77.978γ = 90.00
Software Package:
Software NamePurpose
AMoREphasing
SCALEPACKdata scaling
DENZOdata reduction
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-12-01
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance