1SN6

NMR solution structure of human Saposin C in SDS micelles

Summary for 1SN6

• Entry DOI: 10.2210/pdb1sn6/pdb
• Related: 1M12
• NMR Information: BMRB: 5465,6158
• Descriptor: Proactivator polypeptide (1 entity in total)
• Functional Keywords: 3 disulfide bridges, all alpha-helices, alpha-helices connected by turns, membrane protein
• Biological source: Homo sapiens (human)
• Cellular location: Lysosome: P07602
• Total number of polymer chains: 1
• Total formula weight: 9424.90

Authors

Hawkins, C.A.,de Alba, E.,Tjandra, N. (deposition date: 2004-03-10, release date: 2005-03-01, Last modification date: 2024-11-13)

Primary citation

Hawkins, C.A.,Alba, E.,Tjandra, N.
Solution structure of human saposin C in a detergent environment.
J.Mol.Biol., 346:1381-1392, 2005

PubMed Abstract: Saposin C is a lysosomal, membrane-binding protein that acts as an activator for the hydrolysis of glucosylceramide by the enzyme glucocerebrosidase. We used high-resolution NMR to determine the three-dimensional solution structure of saposin C in the presence of the detergent sodium dodecyl sulfate (SDS). This structure provides the first representation of membrane bound saposin C at the atomic level. In the presence of SDS, the protein adopts an open conformation with an exposed hydrophobic pocket. In contrast, the previously reported NMR structure of saposin C in the absence of SDS is compact and contains a hydrophobic core that is not exposed to the solvent. NMR data indicate that the SDS molecules interact with the hydrophobic pocket. The structure of saposin C in the presence of SDS is very similar to a monomer in the saposin B homodimer structure. Their comparison reveals possible similarity in the type of protein/lipid interaction as well as structural components differentiating their quaternary structures and functional specificity.

PubMed: 15713488
DOI: 10.1016/j.jmb.2004.12.045

Experimental method

SOLUTION NMR