1qub
CRYSTAL STRUCTURE OF THE GLYCOSYLATED FIVE-DOMAIN HUMAN BETA2-GLYCOPROTEIN I PURIFIED FROM BLOOD PLASMA
OverviewOverview
Human beta(2)-glycoprotein I is a heavily glycosylated five-domain plasma membrane-adhesion protein, which has been implicated in blood coagulation and clearance of apoptotic bodies from the circulation. It is also the key antigen in the autoimmune disease anti-phospholipid syndrome. The crystal structure of beta(2)-glycoprotein I isolated from human plasma reveals an elongated fish-hook-like arrangement of the globular short consensus repeat domains. Half of the C-terminal fifth domain deviates strongly from the standard fold, as observed in domains one to four. This aberrant half forms a specific phospholipid-binding site. A large patch of 14 positively charged residues provides electrostatic interactions with anionic phospholipid headgroups and an exposed membrane-insertion loop yields specificity for lipid layers. The observed spatial arrangement of the five domains suggests a functional partitioning of protein adhesion and membrane adhesion over the N- and C-terminal domains, respectively, separated by glycosylated bridging domains. Coordinates are in the Protein Data Bank (accession No. 1QUB).
About this StructureAbout this Structure
1QUB is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
Adhesion mechanism of human beta(2)-glycoprotein I to phospholipids based on its crystal structure., Bouma B, de Groot PG, van den Elsen JM, Ravelli RB, Schouten A, Simmelink MJ, Derksen RH, Kroon J, Gros P, EMBO J. 1999 Oct 1;18(19):5166-74. PMID:10508150 Page seeded by OCA on Sat May 3 06:42:53 2008