Letter | Published:

Role of the Sulphydryl Group in the Formation of Alkaline Protein Gels

Nature volume 169, pages 10201021 (14 June 1952) | Download Citation

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Abstract

COMMENTING on an account1 from this laboratory of the gelation of alkaline casein dispersions, Wormell2 has suggested that the sulphydryl group is the specific one concerned in gelation and that its oxidation to the disulphide bond provides the most likely cross-linkage. In, work as yet unpublished, we have also considered the possibility of non-methionine sulphur being involved in gelation. The results shown in Table 1 represent the amounts of alkalilabile sulphur liberated from the system lactic casein–sodium hydroxide–water at 25° C. when the ratio of air-dry casein to water is 2:5. At the end of the period of reaction, the glues were dispersed in their own volume of water and 1 N hydrochloric acid added, in excess of that required for precipitation. The appearance of the protein precipitated after treatment at high pH. was distinctly fibrous; milder treatments yielded flocculent precipitates. The hydrogen sulphide evolved was passed through N/10 iodine solution, the protein dispersions being boiled until a negative sulphide test was given by lead acetate. The liberated sulphur was determined by back-titration against N/100 sodium thiosulphate.

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References

  1. 1.

    , , and , Nature, 167, 224 (1951).

  2. 2.

    , Nature, 167, 817 (1951).

  3. 3.

    , J. Biol. Chem., 109, 665 (1935); 112, 671 (1936).

  4. 4.

    , , and , Nature, 167, 592 (1951).

  5. 5.

    , , and , J. Biol. Chem., 138, 141 (1941); 144, 87 (1942).

  6. 6.

    , and , Biochem. J., 39, 7 (1945).

  7. 7.

    , and , Biochem. J., 39, 17 (1945).

  8. 8.

    , and , Abstracts Int. Cong. Biochem., Cambridge, 1949, p. 145.

  9. 9.

    , and , Chem. Ber., 80, 379 (1947).

  10. 10.

    See , in “Fibre Science”, 292 (Textile Institute, Manchester, 1949).

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Affiliations

  1. Division of Forest Products, Commonwealth Scientific and Industrial Research Organization, Melbourne. Dec. 21.

    • H. G. HIGGINS
    • , DALLAS FRASER
    •  & J. F. HAYES

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DOI

https://doi.org/10.1038/1691020a0

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