1EXS

STRUCTURE OF PORCINE BETA-LACTOGLOBULIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.39 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.219 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

A novel pH-dependent dimerization motif in beta-lactoglobulin from pig (Sus scrofa).

Hoedemaeker, F.J.Visschers, R.W.Alting, A.C.de Kruif, K.G.Kuil, M.E.Abrahams, J.P.

(2002) Acta Crystallogr.,Sect.D 58: 480-486


  • PubMed Abstract: 
  • beta-Lactoglobulin (BLG) is a lipocalin and is the major protein in the whey of the milk of cows and other ruminants, but not in all mammalian species. The biological function of BLG is not clear, but a potential role in carrying fatty acids through ...

    beta-Lactoglobulin (BLG) is a lipocalin and is the major protein in the whey of the milk of cows and other ruminants, but not in all mammalian species. The biological function of BLG is not clear, but a potential role in carrying fatty acids through the digestive tract has been proposed. The capability of BLG to aggregate and form gels is often used to thicken foodstuffs. The structure of the porcine form is sufficiently different from other known BLG structures that SIRAS phases had to be measured in order to solve the crystal structure to 2.4 A resolution. The r.m.s. deviation of C(alpha) atoms is 2.8 A between porcine and bovine BLG. Nevertheless, the typical lipocalin fold is conserved. Compared with bovine BLG, the tilted alpha-helix alters the arrangement of surface residues of the porcine form, completely changing the dimerization behaviour. Through a unique pH-dependent domain-swapping mechanism involving the first ten residues, a novel dimer interface is formed at the N-terminus of porcine BLG. The existence of this novel dimer at low pH is supported by gel-filtration experiments. These results provide a rationale for the difference in physicochemical behaviour between bovine and porcine BLG and point the way towards engineering such dimerization motifs into other members of the lipocalin family.


    Organizational Affiliation

    Department of Biophysical and Structural Chemistry, Leiden Institute for Chemistry, Leiden University, Einsteinweg 55, PO Box 9502, 2300 RA Leiden, The Netherlands. hoedemae@chem.leidenuniv.nl




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
BETA-LACTOGLOBULIN
A
160Sus scrofaN/A
Find proteins for P04119 (Sus scrofa)
Go to UniProtKB:  P04119
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NA
Query on NA

Download SDF File 
Download CCD File 
A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
GOL
Query on GOL

Download SDF File 
Download CCD File 
A
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.39 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.219 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 80.605α = 90.00
b = 80.605β = 90.00
c = 78.520γ = 120.00
Software Package:
Software NamePurpose
CCP4data scaling
SCALAdata scaling
ARP/wARPmodel building
MOSFLMdata reduction
REFMACrefinement
SHARPphasing
SOLOMONphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-11-15
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance
  • Version 1.3: 2017-10-04
    Type: Refinement description, Structure summary