To investigate the biosynthesis of the glycosylphosphatidylinositol (GPI) anchor in the granulocytes of paroxysmal nocturnal hemoglobinuria (PNH), the glycolipids of granulocytes from PNH patients and normal volunteers were biosynthetically labeled with [3H]mannose in the presence of tunicamycin. Extracted glycolipids were examined by thin-layer chromatography and compared with known biosynthet...

Glycosylphosphatidylinositol (GPI) anchorage is a common posttranslational modification of eukaryotic proteins. Chemical synthesis of structurally defined GPIs and GPI derivatives is a necessary step toward understanding the properties and functions of these molecules in biological systems. In this work, the synthesis of several functionalized GPI anchors was accomplished using the para-methoxy...

The addition of glycosylphosphatidylinositol (GPI) anchors to proteins is an important posttranslational modification in eukaryotic cells. The complete structural elucidation of GPI anchors is a complex process that requires relatively large amounts of starting material. In this paper, we assess the degree of structural information that can be obtained by applying electrospray mass spectrometry...

Beta2-glycoprotein I (beta2-gpI) is a phospholipid cofactor with anticoagulant properties. A number of biological functions in the coagulation cascade have been attributed to this cofactor. Sera from patients with antiphospholipid syndrome (APS) frequently react to beta2-gpI in immunoassays. Occasionally, patients with thrombotic diathesis present anti-beta2-gpI antibodies in the absence of oth...

The plasma protein beta2-glycoprotein I (beta2-GPI) is a major target of autoantibodies in patients with the antiphospholipid syndrome. To understand the physiological function of beta2-GPI and its potential role in the pathophysiology of the antiphospholipid syndrome, the binding of beta2-GPI to phospholipid membranes was characterized. The interaction of beta2-GPI with unilamellar vesicles co...

Glycosylphosphatidylinositol (GPI)-anchored proteins have been identified in all eukaryotes. In fungi, structural and biosynthetic studies of GPIs have been restricted to the yeast Saccharomyces cerevisiae. In this article, four GPI-anchored proteins were purified from a membrane preparation of the human filamentous fungal pathogen Aspergillus fumigatus. Using new methodology applied to western...

OBJECTIVE To develop an assay for the measurement of this anti-human beta2-glycoprotein I (abeta2-GPI) METHODS: This study was conducted from September 2004 to December 2006. The patients attending the Rheumatology Clinic were chosen from several centers in the Eastern region of Saudi Arabia because they had complications. An enzyme-linked immunosorbent ELISA assay was optimized and developed t...

The functional specificity conferred by glycophosphatidylinositol (GPI) anchors on certain membrane proteins may arise from their occupancy of specific membrane microdomains. We show that membrane proteins with noninteractive external domains attached to the same carcinoembryonic antigen (CEA) GPI anchor, but not to unrelated neural cell adhesion molecule GPI anchors, colocalize on the cell sur...

The purpose of this investigation was to re-evaluate the neurotrophic effect of GPI-1046 on neurite outgrowth in vitro. GPI-1046 was synthesized and identified with mass spectrometry, nuclear magnetic resonance and elemental analysis. Chicken dorsal root ganglions (DRGs) were removed and divided into three groups: (1) The DRGs were cultured in DMEM containing different concentrations of GPI-104...

In this study, we have identified a dominant glycolipid toxin of Plasmodium fakiparum. It is a glycosylphosphatidylinositol (GPI). The parasite GPI moiety, free or associated with protein, induces tumor necrosis factor and interleukin I production by macrophages and regulates glucose metabolism in adipocytes. Deacylation with specific pbospholipases abolishes cytokine induction, as do inhibitor...