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Purification of Hsp104, a Protein Disaggregase
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Purification of Hsp104, a Protein Disaggregase

Published on: September 30, 2011

Amidolytic properties of single-chain activated Hageman factor

O D Ratnoff, H Saito

    Proceedings of the National Academy of Sciences of the United States of America
    |March 1, 1979
    PubMed

    Activation of Hageman factor (Factor XII) upon exposure to negatively charged agents has been attributed to proteolytic cleavage of this molecule. To examine this question, purified Hageman factor was exposed to Sephadex gels to which ellagic acid had been adsorbed. Such Hageman factor, separated from the gels and studied in the fluid phase, was amidolytic. Nonetheless, no cleavage of Hageman factor treated in this way could be demonstrated by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. Thus, activation of Hageman factor by negatively charged agents was not necessarily accompanied by molecular scission.

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