Dírkonošci (Foraminifera), mořští prvoci s vápenatou schránkou, obývají naši planetu více než půl miliardy let. Zkoumáním způsobu života těch současných se mnohé dozvíme o jejich pravěkých předcích i o dávných mořích, ve kterých žili., Foraminifera - a rich group of mainly marine microorganisms - are widely used for paleoecological reconstructions. Their occurrence provides important data about past ecological conditions of the sites. We reconstructed former conditions in Židlochovice research site (southern Moravia) by comparing fossil communities with the recent ones present on the island of Rab (Adriatic Sea)., and Anna Poštulková.
Seven species of the genus Trichodina Ehrenberg, 1838 were identified during a sampling programme of twenty freshwater fish species from approximately sixty sites in Scotland, England and Wales. Species found include: Trichodina acuta Lom, 1961 from Cyprinus carpio L., Carassius auralus L., Oncorhynchus mykiss (Walbaum), Salmo trutta L. and Phoxinus phoxinus L.; Trichodina domerguei Wallengren, 1897 from Gasterosteus aculeatuir L.; Trichodina tenuidens Faurc-Fremiet, 1944 from Gasterosteus aculeatus; Trichodina pediculus Ehrenberg, 1838 from Gasterosteus aculeatus; Trichodina modesta Lom, 1970 from Abramis brama L.; Trichodina nigra Lom, 1960 from Cyprinus carpio, Salmo trutta and Oncorhynchus mykiss', and Trichodina intermedia Lom, 1960 from Phoxinus phoxinus. Morphological variation within and between host populations and host specificity of the Trichodina species recovered are described.
Při studiu interakcí bakterií a prvoků se používají zejména metody fluorescenční mikroskopie v kombinaci se značenými bakteriemi, nebo i vysoce specifické fluorescenčně značené RNA-sondy (fluorescence in situ hydridizace), které umožňují i přesnou taxonomickou identifikaci druhů bakterií, pohlcovaných prvoky. Můžeme tak studovat nejenom rychlost, ale i selektivitu eliminace bakterií heterotrofními a mixotrofními bičíkovci a nálevníky v různých přírodních vodách., Trophic interaction between bacteria and protozoa is mainly studied by means of fluorescence microscopy exploiting various fluorescence labelling of bacteria, including highly specific RNA-probes for fluorescence in situ hybridization, which allows precise identification of bacterial species grazed by protozoa. By combining these approaches we can examine not only the total rate of protozoan bacterivory, but also the grazing selectivity of heterotrophic and mixotrophic flagellates and ciliates feeding on bacteria in a broad array of aquatic ecosystems., Karel Šimek., and autor: Redakce a Karel Šimek