Parduczia | |
---|---|
Scientific classification | |
Clade: | SAR |
Infrakingdom: | Alveolata |
Phylum: | Ciliophora |
Subphylum: | Postciliodesmatophora |
Class: | Karyorelictea |
Order: | Protoheterotrichida |
Family: | Geleiidae |
Genus: | Parduczia Dragesco, 1999 |
Species | |
See text. |
Parduczia is a genus of karyorelict ciliates in the family Geleiidae.
Parduczia species are filiform to serpentiform ciliates characterized by their giant size (1200 to 2500 µm on average) and their very long buccal split. [1]
The genus name [lower-alpha 1] is a taxonomic patronym honoring the protistologist Béla Párducz (1911–1964). [3] [4]
Five species are currently described in the genus Parduczia. [1]
Comparison and phylogenetic analysis of 18S rRNA sequences showed that Parduczia orbis is the sister group to Corlissina maricaensis . In turn, these two genera form a clade with Geleia . [5]
An alternative genetic code is used by the nuclear genome of Parduczia sp. [2] This code corresponds to the translation table 27 and involves the unusual reassignment of the three standard termination codons to sense codons:
DNA codons | RNA codons | This code (27) | Standard code (1) | |||
---|---|---|---|---|---|---|
TAA | UAA | Gln(Q) | Ter(*) | |||
TAG | UAG | Gln(Q) | Ter(*) | |||
TGA | UGA | Ter(*) | or | Trp(W) | Ter(*) |
The genetic code is the set of rules used by living cells to translate information encoded within genetic material into proteins. Translation is accomplished by the ribosome, which links proteinogenic amino acids in an order specified by messenger RNA (mRNA), using transfer RNA (tRNA) molecules to carry amino acids and to read the mRNA three nucleotides at a time. The genetic code is highly similar among all organisms and can be expressed in a simple table with 64 entries.
In molecular biology, a stop codon is a codon that signals the termination of the translation process of the current protein. Most codons in messenger RNA correspond to the addition of an amino acid to a growing polypeptide chain, which may ultimately become a protein; stop codons signal the termination of this process by binding release factors, which cause the ribosomal subunits to disassociate, releasing the amino acid chain.
Carl Richard Woese was an American microbiologist and biophysicist. Woese is famous for defining the Archaea in 1977 by phylogenetic taxonomy of 16S ribosomal RNA, a technique he pioneered that revolutionized microbiology. He also originated the RNA world hypothesis in 1967, although not by that name. Woese held the Stanley O. Ikenberry Chair and was professor of microbiology at the University of Illinois at Urbana–Champaign.
The alveolates are a group of protists, considered a major clade and superphylum within Eukarya. They are currently grouped with the stramenopiles and Rhizaria among the protists with tubulocristate mitochondria, the group being referred to as SAR.
Paramecium is a genus of eukaryotic, unicellular ciliates, commonly studied as a representative of the ciliate group. Paramecia are widespread in freshwater, brackish, and marine environments and are often very abundant in stagnant basins and ponds. Because some species are readily cultivated and easily induced to conjugate and divide, it has been widely used in classrooms and laboratories to study biological processes. Its usefulness as a model organism has caused one ciliate researcher to characterize it as the "white rat" of the phylum Ciliophora.
The Labyrinthulomycetes (ICBN) or Labyrinthulea (ICZN) are a class of protists that produce a network of filaments or tubes, which serve as tracks for the cells to glide along and absorb nutrients for them. The two main groups are the labyrinthulids and thraustochytrids. They are mostly marine, commonly found as parasites on algae and seagrasses or as decomposers on dead plant material. They also include some parasites of marine invertebrates.
Karyorelictea is a class of ciliates in the subphylum Postciliodesmatophora. Most species are members of the microbenthos community, that is, microscopic organisms found in the marine interstitial habitat, though one genus, Loxodes, is found in freshwater.
Loxodes is a genus of karyorelictean ciliates, belonging to family Loxodidae. It is the only known karyorelictean ciliate that lives in freshwater habitats.
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.
The karyorelictid nuclear code is a genetic code used by the nuclear genome of the Karyorelictea ciliate Parduczia sp.
Condylostoma is a genus of unicellular ciliate protists, belonging to the class Heterotrichea.
Remanella is a genus of karyorelict ciliates, belonging to family Loxodidae. Whereas Remanella inhabits brackish and marine waters, Loxodes – the other loxodid genus – is a freshwater taxon.
Protoheterotrichida is an order of karyorelict ciliates. It contains the family Geleiidae.
Geleiidae is a family of karyorelict ciliates. It is sometimes synonymized with family Aveliidae.
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.
Wilbertomorphidae is a family of karyorelictean ciliates. The family is monotypic, because it contains a single genus Wilbertomorpha with a single known species, Wilbertomorpha colpoda.
Tracheloraphis is a genus of ciliates in the family Trachelocercidae.
Geleia is a genus of karyorelict ciliates in the family Geleiidae.
Gellertia is a monotypic genus of karyorelict ciliates in the family Geleiidae. It contains a single species, Gellertia heterotricha.
Corlissina is a genus of karyorelict ciliates in the family Geleiidae. Only the type species Corlissina maricaensis is assigned to this genus.