2DOB

Crystal Structure of Human Saposin A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.218 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structures of saposins A and C.

Ahn, V.E.Leyko, P.Alattia, J.R.Chen, L.Prive, G.G.

(2006) Protein Sci. 15: 1849-1857

  • DOI: 10.1110/ps.062256606
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Saposins A and C are sphingolipid activator proteins required for the lysosomal breakdown of galactosylceramide and glucosylceramide, respectively. The saposins interact with lipids, leading to an enhanced accessibility of the lipid headgroups to the ...

    Saposins A and C are sphingolipid activator proteins required for the lysosomal breakdown of galactosylceramide and glucosylceramide, respectively. The saposins interact with lipids, leading to an enhanced accessibility of the lipid headgroups to their cognate hydrolases. We have determined the crystal structures of human saposins A and C to 2.0 Angstroms and 2.4 Angstroms, respectively, and both reveal the compact, monomeric saposin fold. We confirmed that these two proteins were monomeric in solution at pH 7.0 by analytical centrifugation. However, at pH 4.8, in the presence of the detergent C(8)E(5), saposin A assembled into dimers, while saposin C formed trimers. Saposin B was dimeric under all conditions tested. The self-association of the saposins is likely to be relevant to how these small proteins interact with lipids, membranes, and hydrolase enzymes.


    Organizational Affiliation

    Department of Medical Biophysics, University of Toronto, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Proactivator polypeptide
A
83Homo sapiensMutation(s): 0 
Gene Names: PSAP (GLBA, SAP1)
Find proteins for P07602 (Homo sapiens)
Go to Gene View: PSAP
Go to UniProtKB:  P07602
Small Molecules
Ligands 1 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
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.218 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 45.680α = 90.00
b = 50.040β = 90.00
c = 33.820γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
ADSCdata collection
SCALEPACKdata scaling
DENZOdata reduction
SOLVEphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2006-04-28 
  • Released Date: 2006-07-25 
  • Deposition Author(s): Prive, G.G., Ahn, V.E.

Revision History 

  • Version 1.0: 2006-07-25
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance