Deoxyribonucleoproteins from the ciliate Tetrahymena pyriformis GL.

Microtubules from the Cilia of Tetrahymena Pyriformis

Frayed cilia from Tetrahymena pyriformis have been examined in the electron microscope using both uranyl acetate and phosphotungstic acid as negative stains. Observations on the central microtubules show that one member of the pair exhibits two rows of short projections. These are about 18 nm long, and are spaced longitudinally at 16-nm intervals. In many specimens the projections are separated...

Studies on the metabolism of the Protozoa. III. Metabolism of the ciliate Tetrahymena pyriformis (Glaucoma piriformis).

The Mechanism of the Water Expulsion Vesicle of the Ciliate Tetrahymena Pyriformis

Analysis of high-speed (150 frames/sec) cinematographs of the filling and expulsion of the water expulsion vesicle of Tetrahymena pyriformis shows that the vesicle fills as water is pumped into it by contractions of at least four ampullary sacs which are continuous with the endoplasmic reticulum. When filled, the vesicle is pressed against its two excretory pores by cyclotic movements of the cy...

Chemotactic effect of odorants and tastants on the ciliate Tetrahymena pyriformis.

Naturally occurring aroma compounds are able to elicit physiological and migratory responses such as chemotaxis even at nano to femtomolar concentrations in organisms at different levels of phylogeny. Despite the amazing chemical variety of these substances the apparatus by which they can be detected i.e. the chemosensory receptors and the signaling pathways seem to be rather uniform and evolut...

Arsenate toxicity and stress responses in the freshwater ciliate Tetrahymena pyriformis.

The arsenic metabolism in different biological organisms has been studied extensively. However, little is known about protozoa. Herein, we investigated the cell stress responses of the freshwater ciliate Tetrahymena pyriformis to arsenate toxicity. An acute toxicity assay revealed an 18-h EC(50) arsenate concentration of ca. 40 μM, which caused significant changes in the cell shape, growth and ...