ABSTRACT
In most species either C reactive protein (CRP) or serum amyloid P component (SAP) are acute phase reactants that increase up to a thousandfold following induction. They share similar subunit composition, calcium-dependent ligand binding capacity and extensive amino acid sequence homology. SAP and CRP have in general different calcium-dependent affinities for the ligands phosphorylethanolamine (PE) and phosphorylcholine (PC). Experimental AA amyloidosis in the mink is used as a model for the amyloid disease process, and it is thus important to characterise the different proteins involved in amyloid formation in this species. SDS-PAGE of PE-purified mink protein showed a major protein band with an apparent molecular mass of 26 kDa, together with one minor band estimated to be 1-by-10 of the major band. The mink protein purified with PC has an identical N-terminal sequence and SDS-PAGE profile as the PE purified protein. It is concluded that the proteins purified with PC and PE are identical.
