Native Human Serum Amyloid P Component is a Single Pentamer
- 1 March 1995
- journal article
- Published by Wiley in Scandinavian Journal of Immunology
- Vol. 41 (3), 263-267
- https://doi.org/10.1111/j.1365-3083.1995.tb03562.x
Abstract
Serum amyloid P component (SAP) and C-reactive protein (CRP) are members of the pentraxin protein family. SAP is the precursor protein to amyloid P component present in all forms of amyloidosis. The prevailing notion is that SAP in circulation has the form of a double pentameric molecule (decamer) whereas CRP is a single pentameric molecule. We have investigated by gel permeation chromatography the M(r) of SAP in freshly collected human serum and of SAP purified by carbohydrate affinity chromatography and anion exchange chromatography. SAP was monitored by quantitative immunoelectrophoresis and ELISA, and SAP peak fractions were analysed by use of SDS-PAGE, Western blotting, and electron microscopy. The results indicate that native SAP circulates as a single pentamer, a part of which forms complexes with C4b-binding protein. The properties of SAP changed during purification as indicated by rocket immunoelectrophoresis and electron microscopy. Thus, electron micrographs of purified SAP showed a predominance of decamers. However, the decamer form of SAP reversed to single pentamers when purified SAP was incorporated into SAP-depleted serum.Keywords
This publication has 22 references indexed in Scilit:
- Calcium‐enhanced aggregation of serum amyloid P component and its inhibition by the ligands heparin and heparan sulphateAPMIS, 1994
- Human serum amyloid P-component (SAP) selectively binds to immobilized or bound forms of C-reactive protein (CRP)Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1992
- Purification, Subunit Characterization and Ultrastructure of Three Soluble Bovine Lectins: Conglutinin, Mannose‐Binding Protein and the Pentraxin Serum Amyloid P‐ComponentScandinavian Journal of Immunology, 1992
- Calcium-dependent polymerization of human serum amyloid P component is inhibited by heparin and dextran sulfateBiochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1989
- A pentameric form of human serum amyloid P component: Crystallization, X-ray diffraction and neutron scattering studiesJournal of Molecular Biology, 1988
- DIAGNOSTIC RADIONUCLIDE IMAGING OF AMYLOID: BIOLOGICAL TARGETING BY CIRCULATING HUMAN SERUM AMYLOID P COMPONENTThe Lancet, 1988
- Specific localization and imaging of amyloid deposits in vivo using 123I-labeled serum amyloid P component.The Journal of Experimental Medicine, 1988
- Fibronectin and C4-binding protein are selectively bound by aggregated amyloid P componentThe Journal of Experimental Medicine, 1981