This report deals with the effect of the mode of feeding of the hindgut-fermenting herbivorous rhinoceros on the species of Protozoa fermenting the ingesta, as demonstrated by the proposed three new species of ciliated Protozoa: Didesmis synciliata differing from D. ovalis in having syncilia in place of simple cilia, Blepharoconus dicerotos being twice the size of B. cervicalis, and Blepharosph...

Evolving multicellularity is easy, especially in phototrophs and osmotrophs whose multicells feed like unicells. Evolving animals was much harder and unique; probably only one pathway via benthic 'zoophytes' with pelagic ciliated larvae allowed trophic continuity from phagocytic protozoa to gut-endowed animals. Choanoflagellate protozoa produced sponges. Converting sponge flask cells mediating ...

The sensitivity of protozoa, and particularly ciliated protozoa, to environmental changes suggested a study on the physiological responses arising from exposure to toxic compounds. Tetrahymena pyriformis was used as a test organism in a set of miniaturized assays. The physiological response of this ciliate was assessed in terms of adenosine-5'-triphosphate content and acid phosphatase activity ...

Recent studies have identified a phenomenon in which ciliated protozoa engulf Salmonella and the intra-protozoal environment hyperactivates virulence gene expression and provides a venue for conjugal transfer of antibiotic resistance plasmids. The former observation is relegated to Salmonella bearing the SGI1 multiresistance integron while the latter phenomenon appears to be a more generalized ...

The nucleotide sequences of 5S rRNAs from three ciliated protozoa, Paramecium tetraurelia, Tetrahymena thermophila and Blepharisma japonicum have been determined. All of them are 120 nucleotides long and the sequence of probable tRNA binding site of position 41-44 is GAAC which is characteristic of the plant 5S rRNAs. The sequence similarity percents are 87% (Paramecium/Tetrahymena), 86% (Param...

Ciliates have available most of the intracellular signaling mechanisms known from metazoans. Long-range signals are represented by firmly installed microtubules serving as gliding rails aiming at specific targets. Many components are distinctly arranged to guarantee locally restricted effects. Short-range signals include Ca, provided from different sources, and proteins for membrane recognition...

An improved silver carbonate impregnation method for marine ciliates is described. Compared to conventional methods, the new method of fixing and staining is easy to learn and yields easily reproducible results. Structures that are impregnated with silver carbonate such as nuclear apparatus, infraciliature as well as cortical and cytoplasmic microtubules and even contractile vacuole pore are st...