Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-12-01T00:30:27.929Z Has data issue: false hasContentIssue false
  • English
  • Français

The chemical composition and some properties of the egg layers in Hymenolepis diminuta eggs

Published online by Cambridge University Press:  06 April 2009

R. C. Lethbridge
R. C. Lethbridge
Affiliation:
Department of Zoology, Imperial College, London, S. W.7*
Get access Rights & Permissions [Opens in a new window]

Summary

1. It has been shown that the protein eggshell of Hymenolepis diminuta eggs was not significantly stabilized by sulphur or electrovalent linkages but was resistant to attack by proteolytic enzymes. Amino acid analysis demonstrated a marked preponderance of aromatic and heterocyclic acids and it has been suggested that these groups act as cross-linking agents in the shell protein.

2. The role of the lipid-containing subshell ‘membrane’ in protecting the enclosed embryo against fluctuations in pH and osmolarity in the external environment and infiltration of enzymes and toxic compounds has been demonstrated.

3. The cytoplasmic layer was shown to consist of a glucosamine-containing mucoprotein present in a dehydrated or semi-dehydrated state in the intact egg.In mechanically damaged eggs the cytoplasmic layer was rapidly dispersed by some proteolytic enzymes.

4. The embryophore enclosing the hexacanth embryo was composed of a sulphurrich protein that was weakened by some proteolytic enzymes and completely destroyed by others.

I should like to thank Professor T. R. E. Southwood, in whose department this work was carried out, and Dr June Mahon for her advice and encouragement.I am particularly grateful to Dr R. A. Wilson, Department of Biology, University of York, for the quantitative amino acid determinations on eggshell hydrolysates and for criticizing this manuscript. This research was conducted during the tenure of a Science Research Council Studentship and formed part of a thesis submitted for the Ph.D. degree, University of London.

Type
Research Article
Information
Parasitology , Volume 63 , Issue 2 , October 1971 , pp. 275 - 288
Copyright
Copyright © Cambridge University Press 1971

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Berntzen, A. K. & voge, M. (1965). In vitro hatching on oncospheres of four Hymenolepid cestodes. Journal of Parasitology 51, 235–42.CrossRefGoogle Scholar
Brown, C. H. (1950). A review of the methods available for the determination of the types of forces stabilizing structural proteins in animals. Quarterly Journal of Microscopical Science 91, 331–9.Google ScholarPubMed
Cheng, T. C. & Dyckman, E. (1964). Sites of glycogen deposition in Hymenolepis diminuta during the growth phase in the rat host. Zeitschrift fur Parasitenkunde 24, 49–64.Google Scholar
Elson, L. A. & Morgan, W. T. U. (1933). A colorimetric method for the determination of glucosamine and chondrosamine. Biochemical Journal 27, 1824–8.CrossRefGoogle ScholarPubMed
Fruton, J. S. & Simmonds, S. (1958). General Biochemistry. New York: John Wiley.Google Scholar
Gilmoub, D. (1965). The Metabolism of Insects Edinburgh and London: Oliver and Boyd.Google Scholar
Goddard, D. R. & Michaelis, L. (1934) A study on keratin. Journal of Biological Chemistry 106, 605–14.CrossRefGoogle Scholar
Hedrick, R. M. (1958). Comparative histochemical studies on cestodes. II. The distribution of fat substances in Hymenolepis diminuta and Raillietina cesticillus. Journal of Parasitology 44, 75–84.CrossRefGoogle ScholarPubMed
Hedrick, R. M. & Daughebty, J. W. (1957). Comparative histochemical studies on cestodes. I. The distribution of glycogen in Hymenolepis diminuta and Raillietina cesticillus. Journal of Parasitology 43, 497–504.CrossRefGoogle ScholarPubMed
Lethbridge, R. C. (1971). The hatching of Hymenolepis diminuta eggs and penetration of hexacanths in Tenebrio molitor beetles. Parasitology 62, 445–456.CrossRefGoogle ScholarPubMed
Llewellyn, J. (1965). The evolution of parasitic platyhelminthes. Symposium of the British Society for Parasitology 3, 47–78.Google Scholar
McIlvaine, T. C. (1921). A buffer solution for colourimetric comparison. Journal of Biological Chemistry 49, 183.CrossRefGoogle Scholar
Ogren, R. E. & Magill, R. M. (1962). Demonstration of protein in the protective envelopes and embryonic muscle in oncospheres of Hymenolepis diminuta, a tape worm of mammals. Proceedings of the Pennsylvanian Academy of Science 36, 160–7.Google Scholar
Pearse, A. G. E. (1961). Histochemistry, Theoretical and Applied. London: J. and A. Churchill.Google Scholar
Pence, D. B. (1970). Electron microscope and histochemical studies on the eggs of Hymenolepis diminuta. Journal of Parasitology 56, 84–97.CrossRefGoogle ScholarPubMed
Prosser, C. J. & Brown, F. A. (1961). Comparative Animal Physiology. London: J. and A. Churchill.Google Scholar
Rybicka, K. (1966).Embryogenesis Hymenolepis diminuta.I. Morphogenesis. Experimental Parasitology 19, 366–79.CrossRefGoogle Scholar
Rybicka, K. (1967). Embryogenesis.in Hymenolepsis diminuta. II. Glycogen distribution in the embryos. Experimental Parasitology 20, 98–105.CrossRefGoogle Scholar
Smith, I. (1961). Chromatographic and Electrophoretic Techniques. Vol. 1. Chromatography. London: Heinemann.Google Scholar
Smyth, J. D. (1954). A technique for the demonstration of polyphenol oxidase and its application to egg-shell formation in helminths and byssus formation. Quarterly Journal of Microscopital Science 95, 139–52.Google Scholar
Smyth, J. D. & Clegg, J. A. (1959). Egg-shell formation in trematodes and cestodes Experimental Parasitology 8, 286–323.Google Scholar
Voge, M. & Berntzen, A. K. (1961). In vitro hatching of oncospheres of Hymenolepsi diminuta (Cestoda: Cyclophyllidea). Journal of Parasitology 47, 813–18.CrossRefGoogle ScholarPubMed
Wilson, R. A. (1967). The structure and permeability of the shell and vitelline membrane of the egg of Fasciola hepatica. Parasitology 57, 47–58.CrossRefGoogle Scholar