• 1 January 1978
    • journal article
    • research article
    • Vol. 92  (1) , 78-83
Abstract
Amyloid AP (protein SAP) was isolated from human serum by affinity chromatography using specific antiserum and shown to have the same immunologic and ultrastructural characteristics as the pentagonal protein isolated from amyloid tissue (AP). Polyacrylamide gel electrophoresis in SDS [sodium dodecyl sulfate] reveals a single subunit of 25,000 daltons for both SAP and AP preparations. N-terminal amino acid sequence of this alpha globulin to 13 residues reveals complete homology with the tissue-extracted protein, suggesting that AP is incorporated into, or adsorbed onto, amyloid fibrils without biochemical alteration.