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A New Type of Phase Rule Solubility Test for Enzyme Purity


IN 1937 Kuhn and Desnuelle1 prepared a highly purified specimen of Warburg's yellow enzyme, and as evidence of purity they pointed out that when ammonium sulphate was added to the solution the yellow colour and the protein began to come out of solution at the same salt concentration, and that the decrease in yellow colour and the decrease in protein content were parallel. They did not develop the test further, nor did they successfully apply it to the analysis of impure solutions.

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  1. Ber. Dtch. Chem. Ges., 70, 1907 (1937).

  2. J. Biol. Chem., 109, 755 (1935).

  3. C.R. Soc. Biol, 121, 1019 (1936).

  4. C.R. Soc. Biol, 122, 231 (1936).

  5. J. Gen. Physiol., 20, 475 (1937).

  6. Physiol. Rev., 5, 349 (1925).

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FALCONER, J., TAYLOR, D. A New Type of Phase Rule Solubility Test for Enzyme Purity. Nature 155, 303–304 (1945).

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