Dataset Information

Chemical Defence by Sterols in the Freshwater Ciliate Stentor polymorphus.

ABSTRACT: Heterotrich ciliates typically retain toxic substances in specialized ejectable organelles, called extrusomes, which are used in predator-prey interactions. In this study, we analysed the chemical defence strategy of the freshwater heterotrich ciliate Stentor polymorphus against the predatory ciliate Coleps hirtus, and the microturbellarian flatworm Stenostomum sphagnetorum. The results showed that S. polymorphus is able to defend itself against these two predators by deploying a mix of bioactive sterols contained in its extrusomes. Sterols were isolated in vivo and characterized by liquid chromatography-mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR), as ergosterol, 7-dehydroporiferasterol, and their two peroxidized analogues. The assessment of the toxicity of ergosterol and ergosterol peroxide against various organisms, indicated that these sterols are essential for the effectiveness of the chemical defence in S. polymorphus.

SUBMITTER: Buonanno F

PROVIDER: S-EPMC9774955 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Chemical Defence by Sterols in the Freshwater Ciliate Stentor polymorphus.

Buonanno Federico F Trenti Francesco F Achille Gabriele G Vallesi Adriana A Guella Graziano G Ortenzi Claudio C

Biology 20221130 12

Heterotrich ciliates typically retain toxic substances in specialized ejectable organelles, called extrusomes, which are used in predator-prey interactions. In this study, we analysed the chemical defence strategy of the freshwater heterotrich ciliate Stentor polymorphus against the predatory ciliate Coleps hirtus, and the microturbellarian flatworm Stenostomum sphagnetorum. The results showed that S. polymorphus is able to defend itself against these two predators by ...[more]

PMID: 36552259

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Dataset Information

Chemical Defence by Sterols in the Freshwater Ciliate Stentor polymorphus.

Publications

Chemical Defence by Sterols in the Freshwater Ciliate <i>Stentor polymorphus</i>.

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