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Rapid Generation of Amyloid from Native Proteins In vitro
05:48

Rapid Generation of Amyloid from Native Proteins In vitro

Published on: December 6, 2013

The amino acid sequence of a major nonimmunoglobulin component of some amyloid fibrils

M Levin, E C Franklin, B Frangione

    The Journal of Clinical Investigation
    |October 1, 1972
    PubMed

    Insights

    Researchers determined the amino acid sequence of the acid-soluble fraction (ASF) protein in amyloid fibrils from familial Mediterranean fever patients. This protein, lacking cysteine, differs from immunoglobulins and is not found in myeloma-associated amyloid.

    Area of Science:

    • Biochemistry
    • Molecular Biology
    • Protein Chemistry

    Background:

    • Amyloid fibrils are associated with various diseases, including familial Mediterranean fever and secondary amyloidosis.
    • The composition of amyloid fibrils is not fully understood, particularly the role of specific protein components.

    Purpose of the Study:

    • To determine the complete amino acid sequence of the acid-soluble fraction (ASF) protein found in amyloid fibrils.
    • To compare the ASF protein sequence with proteins from other amyloidosis types.

    Main Methods:

    • Amino acid sequencing of the purified acid-soluble fraction (ASF) from amyloid fibrils.
    • Partial amino acid sequencing of proteins from secondary amyloidosis patients.

    Main Results:

    • The complete amino acid sequence of the ASF protein was obtained.
    • ASF contains no cysteine and differs from known immunoglobulins.
    • Partial sequences of proteins from secondary amyloidosis were largely identical to ASF, with one exception (alanine-valine interchange).
    • ASF was not detected in myeloma-associated amyloid.

    Conclusions:

    • The acid-soluble fraction (ASF) is a distinct protein component of amyloid fibrils in familial Mediterranean fever.
    • ASF's unique sequence suggests a specific role in amyloid formation.
    • Further research is needed to elucidate ASF's function and its relationship to other amyloid proteins.

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