Paramecium biaurelia | |
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Paramecium biaurelia with large nucleus and smaller vacuole containing bacteria | |
Scientific classification | |
Domain: | Eukaryota |
Clade: | Diaphoretickes |
Clade: | SAR |
Clade: | Alveolata |
Phylum: | Ciliophora |
Class: | Oligohymenophorea |
Order: | Peniculida |
Family: | Parameciidae |
Genus: | Paramecium |
Species: | P. biaurelia |
Binomial name | |
Paramecium biaurelia | |
Paramecium biaurelia is a species of unicellular ciliates under the genus Paramecium , and one of the cryptic species of Paramecium aurelia . [2] It is a free-living protist in water bodies and harbours several different bacteria as endosymbionts. [3] [4] [5] Although the bacteria are parasites by definition, they also exhibit mutual relationship with the protist by providing survival benefits. [6] It is used as an organism model in the study of the effects of gravitational forces in different environments. [7] [8] [9]
Paramecium biaurelia was described by Tracy Morton Sonneborn in 1975 while analysing the different cryptic species of P. aurelia. [1]
Paramecium biaurelia is a unicellular protist with elongated body, which measures about 133 μm in length. The distinguishing feature from other species of P. aurelia is that it reproduces at below 21°C and specifically between 9 PM and 7 AM. [10] It is also genetically distinct (clade) without any indication of genetic mixing (gene flow) with other cryptic species. [11]
The most important bacterial endosymbionts are Holospora caryophila, [12] Caedibacter paraconjugatus, [5] and ( Candidatus ) Bealeia paramacronuclearis, which are members of the family Rickettsiaceae, and (Candidatus) Fokinia cryptica, which belongs to the family Midichloriaceae. [4] The bacteria are gram-negative species. They are energy parasites as they depend on the host's ATP for their energetic functions, but they increase the growth rate of the protists in return. [6] H. caryophila can infect P. biaurelia and P. caudatum , and was reclassified into a new genus as Preeria caryophila, based on detailed morphological analysis and phylogeny. [13]
P. caryophila are parasitic inside the nucleus of P. biaurelia. As with other species of Holospora, they rely on the protist for amino acids, energy metabolic pathways including glycolysis and the citric acid cycle, as well as for nucleotides. [14] In contrast, Bealeia paramacronuclearis and Fokinia cryptica are cytoplasmic parasites. Bealeia paramacronuclearis are spherical or oval shaped measuring about 1.8 to 2.4 μm long and 0.4 to 0.5 μm broad. Inside the protist, they are arranged in clusters of about 7 to 8 cells in parallel lines. They mostly lie close to the macronucleus (the reason for the species name) and sometimes appear attached to the nuclear envelope. Fokinia cryptica are smaller with the diameter 0.35 to 0.40 μm. They are more randomly distributed in the cytoplasm. [4]
Paramecium biaurelia is present in Europe, Asia, Australia, New Zealand, Tasmania, and North and South America. [15] It is most abundant in cold to moderate climates but does not occur in the tropics. [2]
The plagiopylids are a small order of ciliates, including a few forms common in anaerobic habitats.
The Litostomatea are a class of ciliates. The group consists of three subclasses: Haptoria, Trichostomatia and Rhynchostomatia. Haptoria includes mostly carnivorous forms such as Didinium, a species of which preys primarily on the ciliate Paramecium. Trichostomatia (trichostomes) are mostly endosymbionts in the digestive tracts of vertebrates. These include the species Balantidium coli, which is the only ciliate parasitic in humans. The group Rhynchostomatia includes two free-living orders previously included among the Haptoria, but now known to be genetically distinct from them, the Dileptida and the Tracheliida.
Paramecium is a genus of eukaryotic, unicellular ciliates, widespread in freshwater, brackish, and marine environments. Paramecia are often abundant in stagnant basins and ponds. Because some species are readily cultivated and easily induced to conjugate and divide, they have been widely used in classrooms and laboratories to study biological processes. Paramecium species are commonly studied as model organisms of the ciliate group and have been characterized as the "white rats" of the phylum Ciliophora.
Tracy Morton Sonneborn was an American biologist. His life's study was ciliated protozoa of the group Paramecium.
Paramecium bursaria is a species of ciliate found in marine and brackish waters. It has a mutualistic endosymbiotic relationship with green algae called Zoochlorella. About 700 Chlorella cells live inside the protist's cytoplasm and provide it with food, while the Paramecium provides the algae with movement and protection. P. bursaria is 80-150 μm long, with a wide oral groove, two contractile vacuoles, and a single micronucleus as well as a single macronucleus. P. bursaria is the only species of Paramecium that forms symbiotic relationships with algae, and it is often used in biology classrooms both as an example of a protozoan and also as an example of symbiosis.
Didinium is a genus of unicellular ciliates with at least ten accepted species. All are free-living carnivores. Most are found in fresh and brackish water, but three marine species are known. Their diet consists largely of Paramecium, although they will also attack and consume other ciliates. Some species, such as D. gargantua, also feeds on non-ciliate protists, including dinoflagellates, cryptomonads, and green algae.
Trichonympha is a genus of single-celled, anaerobic parabasalids of the order Hypermastigia that is found exclusively in the hindgut of lower termites and wood roaches. Trichonympha’s bell shape and thousands of flagella make it an easily recognizable cell. The symbiosis between lower termites/wood roaches and Trichonympha is highly beneficial to both parties: Trichonympha helps its host digest cellulose and in return receives a constant supply of food and shelter. Trichonympha also has a variety of bacterial symbionts that are involved in sugar metabolism and nitrogen fixation.
"Candidatus Midichloria" is a candidatus genus of Gram-negative, non-endospore-forming bacteria, with a bacillus shape around 0.45 μm in diameter and 1.2 μm in length. First described in 2004 with the temporary name IricES1, "Candidatus Midichloria" species are symbionts of several species of hard ticks. They live in the cells of the ovary of the females of this tick species. These bacteria have been observed in the mitochondria of the host cells, a trait that has never been described in any other symbiont of animals.
Protozoa are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris. Historically, protozoans were regarded as "one-celled animals".
In biology, Kappa organism or Kappa particle refers to inheritable cytoplasmic symbionts, occurring in some strains of the ciliate Paramecium. Paramecium strains possessing the particles are known as "killer paramecia". They liberate a substance also known as paramecin into the culture medium that is lethal to Paramecium that do not contain kappa particles. Kappa particles are found in genotypes of Paramecium aurelia syngen 2 that carry the dominant gene K.
The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a different undulating pattern than flagella. Cilia occur in all members of the group and are variously used in swimming, crawling, attachment, feeding, and sensation.
Paramecium aurelia are unicellular organisms belonging to the genus Paramecium of the phylum Ciliophora. They are covered in cilia which help in movement and feeding.Paramecium can reproduce sexually, asexually, or by the process of endomixis. Paramecium aurelia demonstrate a strong "sex reaction" whereby groups of individuals will cluster together, and emerge in conjugant pairs. This pairing can last up to 12 hours, during which the micronucleus of each organism will be exchanged. In Paramecium aurelia, a cryptic species complex was discovered by observation. Since then, some have tried to decode this complex using genetic data.
Epixenosomes, also known as Candidatus Epixenosoma, are a genus of bacteria in the phylum Verrucomicrobiota that form a symbiosis with marine ciliates of the genus Euplotidium, where they help to defend their ciliate hosts against predators. It is a monospecific genus, containing only the species Ca. Epixenosoma ejectans.
Paramecium sonneborni is a species of unicellular organisms belonging to the genus Paramecium of the phylum Ciliophora. It was first isolated in Texas and named after Tracy M. Sonneborn. It is a member of the Paramecium aurelia species complex. They are covered in cilia and are distinguished by their difference in mating patterns and enzyme patterns. The length of Paramecium sonneborni is between 130 and 186 μm with a mean length of 154μm. It is the newest member of the Paramecium aurelia species complex. The current Paramecium sonneborni strains, so far, reveal very low viability in the generations and are a result of allopatric speciation.
Holosporales is an order of bacteria.
R bodies are polymeric protein inclusions formed inside the cytoplasm of bacteria. Initially discovered in kappa particles, bacterial endosymbionts of the ciliate Paramecium, R bodies have since been discovered in a variety of taxa.
Armophorea is a class of ciliates in the subphylum Intramacronucleata. . It was first resolved in 2004 and comprises three orders: Metopida, Clevelandellida, and Armophorida. Previously members of this class were thought to be heterotrichs because of similarities in morphology, most notably a characteristic dense arrangement of cilia surrounding their oral structures. However, the development of genetic tools and subsequent incorporation of DNA sequence information has led to major revisions in the evolutionary relationships of many protists, including ciliates. Metopids, clevelandellids, and armophorids were grouped into this class based on similarities in their small subunit rRNA sequences, making them one of two so-called "riboclasses" of ciliates, however, recent analyses suggest that Armophorida may not be related to the other two orders.
Parablepharismea is a class of free-living marine and brackish anaerobic ciliates that form a major clade of obligate anaerobes within the SAL group, together with the classes Muranotrichea and Armophorea.
Novymonas esmeraldas is a protist and member of flagellated trypanosomatids. It is an obligate parasite in the gastrointestinal tract of a bug, and is in turn a host to symbiotic bacteria. It maintains strict mutualistic relationship with the bacteria as a sort of cell organelle (endosymbiont) so that it cannot lead an independent life without the bacteria. Its discovery in 2016 suggests that it is a good model in the evolution of prokaryotes into eukaryotes by symbiogenesis. The endosymbiotic bacterium was identified as member of the genus Pandoraea.
Blepharismidae is a family of unicellular ciliate protists found in fresh and salt water. Two genera are recognized: Blepharisma, which contains some model organisms, and Pseudoblepharisma