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The measurement of the relative turnover rates of proteins of the surface membranes and other fractions of Schistosoma mansoni in culture

Published online by Cambridge University Press:  06 April 2009

J. R. Kusel
Affiliation:
Division of Parasitology, National Institute for Medical Research, London NW7 1AA
Pamela E. Mackenzie
Affiliation:
Division of Parasitology, National Institute for Medical Research, London NW7 1AA

Extract

The double isotope labelling method of Arias, Doyle & Schimke (1969) and Dehlinger & Schimke (1971) was used to determine the relative rates of turnover of proteins in various tissue fractions and in the culture medium of adult Schistosoma mansoni. The majority of proteins in the surface membrane turned over at about the same rate. This is consistent with a model for membrane assembly and degradation involving multi-protein units. The proteins in the other fractions examined, except frozen-thawed supernatant fluid, also turned over at about the same rate. In the frozen and thawed supernatant fluid, the higher molecular weight (>40000 daltons) proteins turned over at a much greater rate than the lower molecular weight proteins (<40000 daltons). The antigens in the culture medium, both particulate and soluble, had a higher turnover rate than the worm tissue proteins. It is concluded that the culture medium antigens are released as the result of two distinct processes: (a) surface membrane turnover and (b) a rapid secretory process. It is possible that the high molecular weight proteins found in the frozen-thawed supernatant fluid are involved in the rapid secretory process. The culture media of 6-day and 16-day schistosomula were also examined by the double isotope method. The culture medium of the adult worm and 16-day schistosomula contains more material presumed to be secreted than does that from the 6-day schistosomula. This may explain the poor immunogenicity of young schistosomula.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1975

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References

Arias, T. M., Doyle, D. & Schimke, R. T. (1969). Studies on the synthesis and degradation of proteins of the endoplasmic reticulum of rat liver. The Journal of Biological Chemistry 244, 3303–15.CrossRefGoogle ScholarPubMed
Clegg, J. A. & Smithers, S. R. (1972). The effects of immune rhesus monkey serum on schistosomula of Schistosoma mansoni during cultivation in vitro. International Journal for Parasitology 2, 7998.CrossRefGoogle ScholarPubMed
Dehlinger, P. J. & Schimke, R. T. (1971). Size distribution of membrane proteins of rat liver and their relative rates of degradation. The Journal of Biological Chemistry 246, 2574–83.Google Scholar
Gurd, J. W. & Evans, W. H. (1973). Relative rates of degradation of mouse-liver surface membrane proteins. European Journal of Biochemistry 36, 273–9.Google Scholar
Hockley, D. J. & McLaren, D. J. (1973). Schistosoma mansoni: changes in the outer membrane of the tegument during development from cercaria to adult worm. International Journal for Parasitology 3, 1325.Google Scholar
Kusel, J. R. (1972). Protein composition and protein synthesis in the surface membranes of Schistosoma mansoni. Parasitology 65, 5569.CrossRefGoogle ScholarPubMed
Kusel, J. R., Mackenzie, P. E. & McLaren, D. J. (1975). The release of membrane antigens into culture by adult Schistosoma mansoni. Parasitology 71, 247–59.CrossRefGoogle ScholarPubMed
Kusel, J. R., Sher, F. A., Perez, H., Clegg, J. A. & Smithers, S. R. (1975). The use of radioactive isotopes in the study of specific schistosome membrane antigens. Isotopes and Radiation in Parasitology IV, pp. 127–43. International Atomic Energy Agency: Vienna.Google Scholar
Laemmli, U. K. (1971). Changes of structural proteins during the assembly of the head of the bacteriophage T4. Nature, London 227, 680–5.CrossRefGoogle Scholar
Maizel, J. V. (1971). Polyacrylamide gel electrophoresis of viral proteins. Advances in Virology 5, 179246.Google Scholar
Perez, H. & Terry, R. J. (1973). The killing of adult Schistosoma mansoni in vitro in the presence of antisera to host antigenic determinants and peritoneal cells. International Journal for Parasitology 3, 499503.CrossRefGoogle ScholarPubMed
Siekevitz, P. (1972). Biological membranes: the dynamics of their organisation. Annual Review of Physiology 34, 117–39.CrossRefGoogle Scholar
Smithers, S. R. & Terry, R. J. (1969). The Immunology of Schistosomiasis. In Advances in Parasitology, vol. 7 (ed. Dawes, B.), pp. 4193. New York and London: New York and London.Google Scholar
Warren, L. & Glick, M. C. (1968). Membranes of animal cells. II. The metabolism and turnover of the surface membrane. Journal of Cell Biology 37, 729–46.CrossRefGoogle Scholar
Wilson, R. A. & Barnes, P. E. (1974). An in vitro investigation of dynamic processes occurring in the schistosome tegument, using compounds known to disrupt secretory processes. Parasitology 68, 259–70.CrossRefGoogle Scholar