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Updated: Feb 23, 2026
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Using Caenorhabditis elegans as a Model System to Study Protein Homeostasis in a Multicellular Organism
Published on: December 18, 2013
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Inactivation of proteolytic enzymes by cestodes
G I Izvekova1, M M Kuklina2, T V Frolova3
1Papanin Institute for Biology of Inland Water, Russian Academy of Sciences, Borok, Nekouzskiy district, Yaroslavskaya oblast, 152741, Russia. izvekov@ibiw.yaroslavl.
Summary
Cestodes from various hosts were found to produce inhibitors that block host digestive enzymes. This suggests a protective mechanism against trypsin, aiding parasite survival in the host intestine.
Area of Science:
- Parasitology
- Biochemistry
- Zoology
Background:
- Cestodes (tapeworms) inhabit the intestines of various hosts, including fish and birds.
- Host digestive enzymes, such as trypsin, pose a threat to intestinal parasites.
- Understanding parasite adaptations is crucial for host-parasite interaction studies.
Purpose of the Study:
- To investigate the inhibitor activity of cestodes against host digestive enzymes.
- To identify specific cestode species exhibiting inhibitory properties.
- To elucidate the potential protective role of these inhibitors.
Main Methods:
- Investigated inhibitor activity of cestodes from sea birds, salt-water fish, and freshwater fish.
- Tested inhibition of commercial trypsin.
- Assessed inhibition of proteinase homogenates from host intestinal mucosa.
Main Results:
- Several cestode species, including Alcataenia larina and Bothriocephalus scorpii, demonstrated significant inhibitor activity.
- The identified cestodes inhibited both commercial trypsin and host intestinal proteinases.
- The findings indicate a broad inhibitory capacity against digestive proteases.
Conclusions:
- Cestodes possess mechanisms to counteract host digestive enzymes.
- The inhibitors produced by cestodes are likely specific for trypsin.
- This specificity suggests a targeted defense against host proteases for parasite survival.
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