Biological Assembly 1  

 3D View: Structure | Electron Density

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 9305.69 
• Atom Count: 609 
• Residue Count: 83 
• Unique protein chains: 1

2GTG

Crystal Structure of Human Saposin C

• DOI: 10.2210/pdb2GTG/pdb

• Classification: LIPID BINDING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli


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

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.4 Å
• R-Value Free: 0.283 
• R-Value Work: 0.211 

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

• PubMed: 16823039 
• DOI: 10.1110/ps.062256606
• Primary Citation of Related Structures:  
  2DOB


• 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 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.

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Organizational Affiliation: 

Department of Medical Biophysics, University of Toronto, Canada.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Proactivator polypeptide	A	83	Homo sapiens	Mutation(s): 0  Gene Names: PSAP (GLBA, SAP1)
Find proteins for P07602 (Homo sapiens) Go to Gene View: PSAP Go to UniProtKB:  P07602

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.4 Å
• R-Value Free: 0.283 
• R-Value Work: 0.211 
• Space Group: P 6₃

Unit Cell:

Length (Å)	Angle (°)
a = 53.204	α = 90.00
b = 53.204	β = 90.00
c = 52.460	γ = 120.00

Software Package:

Software Name	Purpose
AMoRE	phasing
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

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: 2008-05-01
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Advisory, Version format compliance