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Selenomonas
Members of the genus ''Selenomonas'' (motile crescent-shaped bacteria in general) are referred to trivially as selenomonads. The genus ''Selenomonas'' constitutes a group of motile crescent-shaped bacteria and includes species living in the gastrointestinal tracts of animals, in particular the ruminants. A number of smaller forms discovered with the light microscope are now in culture but many, especially the large selenomonads are not, owing to their fastidious and incompletely known growth requirements. Gram stain The family '' Veillonellaceae'' was transferred from the order ''Eubacteriales'' to the new order '' Selenomonadales'' in the new class '' Negativicutes''. Despite most of the members of the ''Bacillota'' staining positive for the Gram stain and being trivially called "low-GC Gram-positives" (''cf.'' Bacterial phyla), members of the '' Negativicutes'' stain Gram-negative and possess a double bilayer. This transfer now appears to have been mistaken. On further exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenomonas Sputigena
''Selenomonas sputigena'' is a species of anaerobe Gram-negative bacteria that is found in the upper respiratory tract of humans. It is the type species of the genus ''Selenomonas'', with the type strain VPI D 19B-28 (ATCC 35185). It is known to cause blood infection (sepsis), gum inflammation (periodontal disease), and tooth decay. It alone cannot damage the tooth enamel, but worsen the damage done by other bacteria such as ''Streptococcus mutans,'' ''Porphyromonas gingivalis'', ''Treponema denticola'', and ''Tannerella forsythia.'' ''S. sputigena'' was first noted by Antonie van Leeuwenhoek in 1683 from his microscopic observation of his own sputum. However, it was first described by Carl Flügge in 1886, giving the name ''Spirillum sputigenum''. In 1922, Erwin Boskamp revised the name as ''S. sputigena,'' which was approved by the Judicial Commission of the International Committee on Systematic Bacteriology in 1958. Discovery and identification ''S. sputigena'' is one of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negativicutes
The Negativicutes are a class of bacteria in the phylum Bacillota, whose members have a peculiar cell wall with a lipopolysaccharide outer membrane which stains gram-negative, unlike most other members of the Bacillota. Although several neighbouring ''Clostridia'' species (firmicute bacteria) also stain gram-negative, the proteins responsible for the unusual diderm structure of the ''Negativicutes'' may have actually been laterally acquired from Pseudomonadota (formerly Proteobacteria). Additional research is required to confirm the origin of the diderm cell envelope in the Negativicutes. Most members of this class are obligate anaerobes, and occur in habitats such as rivers, lakes, and the intestines of vertebrates. They range from spherical forms, such as ''Megasphaera'' and '' Veillonella'', to curved rods, as typified by the selenomonads. '' Selenomonas'' has a characteristic crescent shape, with flagella inserted on the concave side, while ''Sporomusa'' is similar, but n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenomonadales
The Selenomonadales are an order of bacteria within the class Negativicutes; unlike most other members of Bacillota, they are Gram-negative. The phylogeny of this order was initially determined by 16S rRNA comparisons. More recently, molecular markers in the form of conserved signature indels (CSIs) have been found specific for all Selenomonadales species. On the basis of these markers, the Selenomonadales are inclusive of two distinct families, and are no longer the sole order within the Negativicutes. Several CSIs have also been found specific for both families, Sporomusaceae and Selenomonadceae. Samples of bacterial strains within this order have been isolated from the root canals of healthy human teeth. Phylogeny The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). See also * List of bacterial orders * List of bacteria genera This article lists the genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillota
The Bacillota (synonym Firmicutes) are a phylum of bacteria, most of which have Gram-positive cell wall structure. They have round cells, called cocci (singular coccus), or rod-like forms (bacillus). A few Bacillota, such as '' Megasphaera'', '' Pectinatus'', '' Selenomonas'', and '' Zymophilus'' from the class Negativicutes, have a porous pseudo-outer membrane that causes them to stain Gram-negative. Many Bacillota produce endospores, which are resistant to desiccation and can survive extreme conditions. They are found in various environments, and the group includes some notable pathogens. Those in one family, the Heliobacteria, produce energy through anoxygenic photosynthesis. Bacillota play an important role in beer, wine, and cider spoilage. Taxonomy The renaming of phyla such as Firmicutes in 2021 remains controversial among microbiologists, many of whom continue to use the earlier names of long standing in the literature. The name "Firmicutes" was derived from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
-monas
The suffix -monas is used in microbiology for many genera and is intended to mean "unicellular organism". Meaning The suffix -monas found in many genera in microbiology is similar in usage to -bacter, -bacillus, -coccus or -spirillum. The genera with the suffix are not a monophyletic group and the suffix is chosen over -bacter, often simply out of stylistic preferences to match with Greek words. The first genus to be given the suffix -monas was ''Pseudomonas'', a genus of gammaproteobacteria. The generic epithet ''Pseudomonas'' was coined by Walter Migula in 1894, who did not give an etymology.Migula, W. (1900) System der Bakterien, Vol. 2. Jena, Germany: Gustav Fischer. Since the 7th edition of Bergey's manual (=top authority in bacterial nomenclature), other authors have given the etymology to be: Greek (, false) and (, single unit or monad), which can mean "false unit". However, "false unit" conceptually does not make much sense, namely, it does not mean "an organism which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Veillonellaceae
The Veillonellaceae are a family of the Clostridia, formerly known as Acidaminococcaceae. bacterium, Bacteria in this family are grouped together mainly based on genetic studies, which place them among the Bacillota. Supporting this placement, several species are capable of forming endospores. However, they differ from most other Bacillota in having Gram-negative stains. The cell wall composition is peculiar. Members of this family are all obligate anaerobes, and occur in habitats such as rivers, lakes, and the intestines of vertebrates. They range from spherical forms, such as ''Megasphaera'' and ''Veillonella'', to curved rods, as typified by the Selenomonads. ''Selenomonas'' has a characteristic crescent-shape, with flagella inserted on the concave side, while ''Sporomusa'' is similar but non-motile. Their names refer to this distinctive morphology: ''selene'' means moon, and ''musa'' means banana. The name Selenobacteria also refers to some this group. The description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenium
Selenium is a chemical element; it has symbol (chemistry), symbol Se and atomic number 34. It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form. It seldom occurs in this elemental state or as pure ore compounds in Earth's crust. Selenium ( ) was discovered in 1817 by , who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in :Sulfide minerals, metal sulfide ores, where it substitutes for sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores. Minerals that are pure selenide or selenate compounds are rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells. Applications in electronics, once important, have been mostly replaced with silicon semiconductor devices. Selenium is still used in a few types of Direct current, DC power surge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antonie Van Leeuwenhoek
Antonie Philips van Leeuwenhoek ( ; ; 24 October 1632 – 26 August 1723) was a Dutch microbiologist and microscopist in the Golden Age of Dutch art, science and technology. A largely self-taught man in science, he is commonly known as " the Father of Microbiology", and one of the first microscopists and microbiologists. Van Leeuwenhoek is best known for his pioneering work in microscopy and for his contributions toward the establishment of microbiology as a scientific discipline. Raised in Delft, Dutch Republic, Van Leeuwenhoek worked as a draper in his youth and founded his own shop in 1654. He became well-recognized in municipal politics and developed an interest in lensmaking. In the 1670s, he started to explore microbial life with his microscope. Using single-lensed microscopes of his own design and make, Van Leeuwenhoek was the first to observe and to experiment with microbes, which he originally referred to as , or . He was the first to relatively determine t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stanislaus Von Prowazek
Stanislaus Josef Mathias von Prowazek, Edler von Lanow (12 November 1875 Jindřichův Hradec, Bohemia – 17 February 1915, Cottbus), born Stanislav Provázek, was a Czech biologist, zoologist and parasitologist, who along with pathologist Henrique da Rocha Lima (1879-1956) discovered the pathogen of epidemic typhus. As a student in biology at the University of Prague, he was influenced by the teachings of zoologist Berthold Hatschek and philosopher Ernst Mach. Other important influences to his career were immunologist Paul Ehrlich at the Institute for Experimental Therapy in Frankfurt (1901) and zoologist Richard von Hertwig at the University of Munich.Stanislaus von Prowazek @ With |
Gram-negative
Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists of a thin peptidoglycan cell wall sandwiched between an inner ( cytoplasmic) membrane and an outer membrane. These bacteria are found in all environments that support life on Earth. Within this category, notable species include the model organism '' Escherichia coli'', along with various pathogenic bacteria, such as '' Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and '' Yersinia pestis''. They pose significant challenges in the medical field due to their outer membrane, which acts as a protective barrier against numerous antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and the antimicrobial enzyme lysozyme produced by animals as part of their innate immune system. Furthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crescent
A crescent shape (, ) is a symbol or emblem used to represent the lunar phase (as it appears in the northern hemisphere) in the first quarter (the "sickle moon"), or by extension a symbol representing the Moon itself. In Hindu iconography, Hindu Iconography, Shiva is often shown wearing a crescent moon on his head, symbolising his control over time, as well as his attributes of both creation and destruction. It is used as the astrological symbol for Moon (astrology), the Moon, and hence as the alchemical symbol for silver. It was also the emblem of Diana (mythology), Diana/Artemis, and hence represented virginity. In veneration of Mary in the Catholic Church, it is associated with Mary, mother of Jesus. From its use as roof finial in Ottoman architecture, Ottoman mosques, it has also become associated with Islam, and the crescent was introduced as Religious symbolism in the United States military#Muslim, chaplain badge for Muslim United States military chaplains in 1993.On Dece ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaerobic
Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: *Adhesive#Anaerobic, Anaerobic adhesive, a bonding agent that does not cure in the presence of air *Anaerobic respiration, respiration in the absence of oxygen, using some other molecule as the final electron acceptor **Anaerobic organism, any organism whose redox metabolism does not depend on free oxygen **Anammox, anaerobic ammonium oxidation, a globally important microbial process of the nitrogen cycle **Anaerobic filter, an anaerobic digester with a tank containing a filter medium where anaerobic microbes can establish themselves **Anaerobic digestion, the use of anaerobic bacteria to break down waste, with biogas as a byproduct ***Anaerobic clarigester, an anaerobic digester that treats dilute biodegradable feedstocks and allows different retention times for solids an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
