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Mitochondrial Trifunctional Protein
A mitochondrion () is an organelle found in the cells of most eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'', meaning a thread-like granule, was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase popularized by Philip Siekevitz in a 1957 ''Scientific American'' article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). The multicellular animal '' Henneguya salminicola'' is known to have retained mitochondrion-related organelles despite a complete loss of their mitochondrial genome. A large number of unicellular organisms, such as microsporidia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell (biology)
The cell is the basic structural and functional unit of all life, forms of life. Every cell consists of cytoplasm enclosed within a Cell membrane, membrane; many cells contain organelles, each with a specific function. The term comes from the Latin word meaning 'small room'. Most cells are only visible under a light microscope, microscope. Cells Abiogenesis, emerged on Earth about 4 billion years ago. All cells are capable of Self-replication, replication, protein synthesis, and cell motility, motility. Cells are broadly categorized into two types: eukaryotic cells, which possess a Cell nucleus, nucleus, and prokaryotic, prokaryotic cells, which lack a nucleus but have a nucleoid region. Prokaryotes are single-celled organisms such as bacteria, whereas eukaryotes can be either single-celled, such as amoebae, or multicellular organism, multicellular, such as some algae, plants, animals, and fungi. Eukaryotic cells contain organelles including Mitochondrion, mitochondria, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philip Siekevitz
Philip Siekevitz (February 25, 1918 – December 5, 2009) was an American cell biologist who spent most of his career at Rockefeller University. He was involved in early studies of protein synthesis and trafficking, established purification techniques to facilitate study of the cell nucleus, worked with Nobel Prize in Physiology or Medicine winner George Palade on cell membrane dynamics, and published extensively on the subject of postsynaptic density. Early life and education Siekevitz was born on February 25, 1918, in Philadelphia to a working-class immigrant family. He spent two years after high school working to save money for his college education, and then began at the Philadelphia College of Pharmacy and Science. He was drafted into the United States Army during his senior year, but deferred his service until after his graduation in 1942. He then served in the army for almost four years, first in a chemical warfare response unit and later as a laboratory technician. Si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streblomastix
A symbiotic eukaryote that lives in the hindgut of termites, ''Streblomastix'' is a protist associated with a community of ectosymbiotic bacteria. Motility ''Streblomastix'' moves by beating its anterior flagella. Morphology These protists A protist ( ) or protoctist is any Eukaryote, eukaryotic organism that is not an animal, Embryophyte, land plant, or fungus. Protists do not form a Clade, natural group, or clade, but are a Paraphyly, paraphyletic grouping of all descendants o ... measure around 100 micrometers in length. They completely lack mitochondria. References *http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artmar03/rhtermite.html *http://www.ucmp.berkeley.edu/protista/basalprotists.html {{Taxonbar, from=Q7622748 Metamonads Metamonad genera Anaerobes Microorganisms Symbiosis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocercomonoides
''Monocercomonoides'' is a genus of flagellate Excavata belonging to the order Oxymonadida. It was established by Bernard V. Travis and was first described as those with "polymastiginid flagellates having three anterior Flagellum, flagella and a trailing one originating at a single basal granule located in front of the anteriorly positioned cell nucleus, nucleus, and a more or less well-defined axostyle". It is the first eukaryotic genus to be found to completely lack Mitochondrion, mitochondria, and all hallmark proteins responsible for mitochondrial function. The genus also lacks any other Mitochondrion#Origin and evolution, mitochondria related organelles (MROs) such as hydrogenosomes or mitosomes. Data suggests that the absence of mitochondria is not an ancestral feature, but rather due to secondary loss. ''Monocercomonoides ''sp. was found to obtain energy through an enzymatic action of nutrients absorbed from the environment. The genus has replaced the Iron–sulfur protein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxymonad
The Oxymonads (or Oxymonadida) are a group of flagellated protists found exclusively in the intestines of animals, mostly termites and other Xylophagy, wood-eating insects. Along with the similar parabasalid flagellates, they harbor the Symbiosis, symbiotic bacterium, bacteria that are responsible for breaking down cellulose. There is no evidence for presence of Mitochondrion, mitochondria (not even anaerobic mitochondrion-like organelles like hydrogenosomes or mitosomes) in oxymonads and three species have been shown to completely lack any molecular markers of mitochondria. It includes e.g. ''Dinenympha'', ''Pyrsonympha'', ''Oxymonas'', ''Streblomastix'', ''Monocercomonoides'', and ''Blattamonas''. Characteristics Most Oxymonads are around 50 μm in size and have a single cell nucleus, nucleus, associated with four Flagellum, flagella. Their Basal body, basal bodies give rise to several long sheets of microtubules, which form an organelle called an axostyle, but different in st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitosome
A mitosome (also called a ''crypton'' in early literature) is a mitochondrion-related organelle (MRO) found in a variety of parasitic unicellular eukaryotes, such as members of the supergroup Excavata. The mitosome was first discovered in 1999 in ''Entamoeba histolytica,'' an intestinal parasite of humans, and mitosomes have also been identified in several species of Microsporidia and in '' Giardia intestinalis''. The mitosome has been detected only in anaerobic or microaerophilic eukaryotes which do not have fully developed mitochondria, and hence do not have the capability of gaining energy from mitochondrial oxidative phosphorylation. The functions of mitosomes, while varied, have not yet been well characterized, but they may be associated with sulfate metabolism and biosynthesis of phospholipids and Fe–S clusters. Mitosomes, like other MROs, likely evolved from mitochondria, based on similarities in structure, function, and biochemical signaling pathways, and may have conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogenosome
A hydrogenosome is a membrane-enclosed organelle found in some Anaerobic organism, anaerobic Ciliate, ciliates, Flagellate, flagellates, Fungus, fungi, and three species of Loricifera, loriciferans. Hydrogenosomes are highly variable organelles that have presumably evolved from protoMitochondrion, mitochondria to produce molecular hydrogen and Adenosine triphosphate, ATP in anaerobic conditions. Hydrogenosomes were discovered in 1973 by D. G. Lindmark and M. Müller. Because hydrogenosomes hold evolutionary lineage significance for organisms living in anaerobic or oxygen-stressed environments, many research institutions have since documented their findings on how the organelle differs in various sources. History Hydrogenosomes were isolated, purified, biochemically characterized and named in the early 1970s by Lindmark and Müller at Rockefeller University. In addition to this seminal study on hydrogenosomes, they also demonstrated for the first time the presence of Pyruvate:fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplomonad
The diplomonads (Greek for "two units") are a group of flagellates, most of which are parasitic. They include ''Giardia duodenalis'', which causes giardiasis in humans. They are placed among the metamonads, and appear to be particularly close relatives of the retortamonads. Morphology Most diplomonads are double cells: they have two nuclei, each with four associated flagella, arranged symmetrically about the body's main axis. Like the retortamonads, they lack both mitochondria and Golgi apparatuses. However, they are now known to possess modified mitochondria, in the case of ''G. duodenalis'', called mitosomes. These are not used in ATP synthesis the way mitochondria are, but are involved in the maturation of iron-sulfur proteins. Possible sexual reproduction in ''Giardia'' The common intestinal parasite ''Giardia duodenalis'' (synonyms ''Giardia lamblia'', ''G. intestinalis'') was once considered to be a descendant of a protist lineage that predated the emergence of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parabasalid
The parabasalids are a group of flagellated protists within the supergroup Excavata. Most of these eukaryotic organisms form a symbiosis, symbiotic relationship in animals. These include a variety of forms found in the intestines of termites and cockroaches, many of which have symbiotic bacteria that help them digest cellulose in woody plants. Other species within this supergroup are known parasites, and include human pathogens. Characteristics The flagella are arranged in one or more clusters near the anterior of the cell. Their basal bodies are linked to parabasal fibers that are associated with a prominent Golgi apparatus, Golgi complex, together forming a parabasal apparatus distinctive to the group. Attachment of a parabasal fiber to the first Golgi cisterna by thin filaments has been reported in ''Tritrichomonas foetus''. Usually they also give rise to a sheet of cross-like microtubules that runs down the center of the cell and in some cases projects past the end. This i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsporidia
Microsporidia are a group of spore-forming unicellular parasites. These spores contain an extrusion apparatus that has a coiled polar tube ending in an anchoring disc at the apical part of the spore.Franzen, C. (2005). How do Microsporidia invade cells?. Folia Parasitologica, 52(1–2), 36–40. doi.org/10.14411/fp.2005.005 They were once considered protozoans or protists, but are now known to be fungi, or a sister group to true fungi. These fungal microbes are obligate eukaryotic parasites that use a unique mechanism to infect host cells. They have recently been discovered in a 2017 Cornell study to infect Coleoptera (beetles) on a large scale. So far, about 1500 of the probably more than one million species are named. Microsporidia are restricted to animal hosts, and all major groups of animals host microsporidia. Most infect insects, but they are also responsible for common diseases of crustaceans and fish. The named species of microsporidia usually infect one host species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unicellular Organism
A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. Organisms fall into two general categories: prokaryotic organisms and eukaryotic organisms. Most prokaryotes are unicellular and are classified into bacteria and archaea. Many eukaryotes are multicellular, but some are unicellular such as protozoa, unicellular algae, and unicellular fungi. Unicellular organisms are thought to be the oldest form of life, with early organisms emerging 3.5–3.8 billion years ago. Although some prokaryotes live in colonies, they are not specialised cells with differing functions. These organisms live together, and each cell must carry out all life processes to survive. In contrast, even the simplest multicellular organisms have cells that depend on each other to survive. Most multicellular organisms have a unicellular life-cycle stage. Gametes, for example, are reprodu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henneguya Zschokkei
''Henneguya zschokkei'' or ''Henneguya salminicola'' is a species of a myxosporean endoparasite. It afflicts several salmon and trout in the genera ''Oncorhynchus'' and ''Salmo'','' ''where it causes milky flesh or tapioca disease''. H. zschokkei'' does not require oxygen to survive and is notable for being one of the few multicellular organisms in the animal kingdom to rely on an exclusively anaerobic metabolism. It is also notable for its lack of both mitochondria and mitochondrial DNA.'''' Description ''Henneguya zschokkei'' is found in fish as an ovoid spore with two anterior polar capsules and two long caudal appendages. Individuals are very small (about 10 micrometers in diameter), but are found aggregated into cysts 3–6 mm in diameter at any place in the animal's musculature. Metabolism ''H. zschokkei'' is incapable of aerobic respiration, making it one of a handful of truly anaerobic animals.; Lay summary: It also lacks a mitochondrial genome and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
