PDB ID or protein name

1n69 » Saposin B (peptide 195-273), structure 1

1n69 » Saposin B (peptide 195-273), structure 1
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Topology in Lysosome membrane
Topologyout side
in side
1n69 » Saposin B (peptide 195-273), structure 1
Depth 1.2 ± 1.0 Å
Tilt Angle 58 ± 6°
ΔGtransfer -2.4 kcal/mol
Links to 1n69 PDB Sum, PDB, SCOP, MSD, OCA, MMDB
Topology out
Resolution 2.2 Å
Other PDB entries representing this structure none
Number of subunits 2
Experimental Verification for 1n69 » Saposin B (peptide 195-273), structure 1
It was suggested that a more "open" conformation of saposin B interacts with lipid bilayers (Ahn et al. 2003). Saposin B extracts phospholipids from the lipid surface; the binding is optimal at low pH values (Ciaffoni et al. 2006).
2 references
Ahn VE, Faull KF, Whitelegge JP, Fluharty AL, Prive GG. 2003. Crystal structure of saposin B reveals a dimeric shell for lipid binding.Proc Natl Acad Sci U S A. 100:38-43. PubMed
Ciaffoni F, Tatti M, Boe A, Salvioli R, Fluharty A, Sonnino S, Vaccaro AM. 2006. Saposin B binds and transfers phospholipids. J Lipid Res. 47: 1045-1053. PubMed
Comments on 1n69 » Saposin B (peptide 195-273), structure 1
Saposins A, B, C, and D are small lysosomal glycoproteins released by proteolysis from a single precursor polypeptide, prosaposin. Saposin B is an activator protein that can extract lipids from membranes. This protein undergoes conformational changes upon association with membranes. This structure is complex with phosphatidylethanolamine.