Among protozoa, Tetrahymena pyriformis is the most commonly ciliated model used for laboratory research. All living organisms need to adapt to ever changing adverse conditions in order to survive. This article focuses on the phenomenon that exposure to toxic doses of the toxicants protects against a normally harmful dose of the same stressor. This first encounter by toxicant provokes the phenom...

Cellular neutral lipid content of Paramecium primaurelia was measured during culture and clonal life using nile red (9-diethylamino-5H-benzo[alpha] phenoxazine-5-one), a dye utilized for lipid analysis in both mammalian cells and in ciliated protozoa. Lipid droplets in P. primaurelia are concentrated in the anterior pole of the cell; their number is maximum in early log phase cells and decrease...

The excision of internal eliminated sequences (IESs) from the germline micronuclear DNA occurs during the differentiation of a new macronuclear genome in ciliated protozoa. In Paramecium, IESs are generally short (28-882 bp), AT rich DNA elements that show few conserved sequence features with the exception of an inverted-terminal-repeat consensus sequence that has similarity to the ends of mari...

HAP2, a male-gamete-specific protein conserved across vast evolutionary distances, has garnered considerable attention as a potential membrane fusogen required for fertilization in taxa ranging from protozoa and green algae to flowering plants and invertebrate animals [1-6]. However, its presence in Tetrahymena thermophila, a ciliated protozoan with seven sexes or mating types that bypasses the...

Ciliated protozoa have two functionally distinct nuclei, a micronucleus (MIC) and a macronucleus (MAC) [1]. These two nuclei are distinct in size, transcriptional activity, and division cycle control, proceeding with cycles of DNA replication and nuclear division at different times within the same cell [2, 3]. The structural basis generating functionally distinct nuclei remains unknown. Here, w...

During macronuclear differentiation in ciliated protozoa a series of programed DNA reorganization processes occur. These include the elimination of micronuclear-specific DNA sequences, the specific fragmentation of the genome into small gene-sized DNA molecules, the de novo addition of telomeric sequences to these DNA molecules and the specific amplification of the remaining DNA molecules. Rece...

The aim of this research was to study the ciliated protozoa community at three sampling stations that receive different levels of domestic sewage along the São Pedro Stream in the municipality of Juiz de Fora, Minas Gerais, Brazil, in order to determine the influence of organic pollution on this community and to assess the feasibility of using ciliates as water quality indicators. Four physical...

In this paper we provide a novel approach for breaking a significant class of block ciphers, the so-called SPN ciphers, using the process of gene assembly in ciliates. Our proposed scheme utilizes, for the first time, the Turing-powerful potential of gene assembly procedure of ciliated protozoa into the real world computations and has a fewer number of steps than the other proposed schemes to b...

The ecology of microbial populations in water and wastewater environments has been extensively studied (Barcina et al., 1997; Scott et al., 2002; Sinton et al., 1994). Commonly, the reduction of fecal indicator bacteria is attributed to biotic and non-biotic factors such as predation, nutrient scarcity, temperature, osmotic stress and visible light. But these factors could affect these bacteria...

Fission yeast Pot1 (protection of telomeres) is a single-stranded telomeric DNA binding protein with a critical role in ensuring chromosome stability. A putative human homolog (hPot1) was previously identified, based on moderate sequence similarity with fission yeast Pot1 and telomere end-binding proteins from ciliated protozoa. Using indirect immunofluorescence, we show here that epitope-tagge...