1c1z
From Proteopedia
|
CRYSTAL STRUCTURE OF HUMAN BETA-2-GLYCOPROTEIN-I (APOLIPOPROTEIN-H)
Contents |
Overview
The high affinity of human plasma beta2-glycoprotein I (beta(2)GPI), also known as apolipoprotein-H (ApoH), for negatively charged phospholipids determines its implication in a variety of physiological pathways, including blood coagulation and the immune response. beta(2)GPI is considered to be a cofactor for the binding of serum autoantibodies from antiphospholipid syndrome (APS) and correlated with thrombosis, lupus erythematosus and recurrent fetal loss. We solved the beta(2)GPI structure from a crystal form with 84% solvent and present a model containing all 326 amino acid residues and four glycans. The structure reveals four complement control protein modules and a distinctly folding fifth C-terminal domain arranged like beads on a string to form an elongated J-shaped molecule. Domain V folds into a central beta-spiral of four antiparallel beta-sheets with two small helices and an extended C-terminal loop region. It carries a distinct positive charge and the sequence motif CKNKEKKC close to the hydrophobic loop composed of residues LAFW (313-316), resulting in an excellent counterpart for interactions with negatively charged amphiphilic substances. The beta(2)GPI structure reveals potential autoantibody-binding sites and supports mutagenesis studies where Trp316 and CKNKEKKC have been found to be essential for the phospholipid-binding capacity of beta(2)GPI.
Disease
Known disease associated with this structure: Apolipoprotein H deficiency OMIM:[138700]
About this Structure
1C1Z is a Single protein structure of sequence from Homo sapiens with and as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of human beta2-glycoprotein I: implications for phospholipid binding and the antiphospholipid syndrome., Schwarzenbacher R, Zeth K, Diederichs K, Gries A, Kostner GM, Laggner P, Prassl R, EMBO J. 1999 Nov 15;18(22):6228-39. PMID:10562535
Page seeded by OCA on Thu Feb 21 12:01:39 2008
