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Streptomyces Toxytricini
''Streptomyces toxytricini'' is a Gram-positive bacterium belonging to the genus ''Streptomyces''. It produces the pancreatic lipase inhibitor lipstatin, of which the antiobesity drug orlistat Orlistat, sold under the brand name Xenical among others, is a medication used to treat obesity. Its primary function is preventing the absorption of fats from the human diet by acting as a lipase inhibitor, thereby reducing caloric intake. It ... is a derivative. References Further reading * External linksType strain of ''Streptomyces toxytricini'' at Bac''Dive'' - the Bacterial Diversity Metadatabase toxytricini Bacteria described in 1957 {{Streptomyces-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinomycetota
The ''Actinomycetota'' (or ''Actinobacteria'') are a phylum of all gram-positive bacteria. They can be terrestrial or aquatic. They are of great economic importance to humans because agriculture and forests depend on their contributions to soil systems. In soil they help to decompose the organic matter of dead organisms so the molecules can be taken up anew by plants. While this role is also played by fungi, ''Actinomycetota'' are much smaller and likely do not occupy the same ecological niche. In this role the colonies often grow extensive mycelia, like a fungus would, and the name of an important order of the phylum, '' Actinomycetales'' (the actinomycetes), reflects that they were long believed to be fungi. Some soil actinomycetota (such as ''Frankia'') live symbiotically with the plants whose roots pervade the soil, fixing nitrogen for the plants in exchange for access to some of the plant's saccharides. Other species, such as many members of the genus '' Mycobacterium'', ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinomycetia
The Actinomycetia are a class of bacteria. Taxonomy The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). * Acidothermales Sen et al. 2014 * Actinomycetales Buchanan 1917 (Approved Lists 1980) * Actinopolysporales Goodfellow and Trujillo 2015 * Bifidobacteriales Stackebrandt et al. 1997 * Catenulisporales Donadio et al. 2015 * Cryptosporangiales Nouioui et al. 2018 * Frankiales Sen et al. 2014 * Geodermatophilales Sen et al. 2014 * Glycomycetales Labeda 2015 * Jatrophihabitantales Salam et al. 2020 * Jiangellales Tang et al. 2015 * Kineosporiales Kämpfer 2015 * Micrococcales Prévot 1940 (Approved Lists 1980) * Micromonosporales Genilloud 2015 * Mycobacteriales Janke 1924 (Approved Lists 1980) * Nakamurellales Sen et al. 2014 * Propionibacteriales (Rainey et al. 1997) Patrick and McDowell 2015 * Pseudonocardiales Labeda and Goodfellow 2015 * Sporichthyales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomycetales
The ''Streptomycetaceae'' are a family of ''Actinomycetota'', making up the monotypic order ''Streptomycetales''. It includes the important genus ''Streptomyces''. This was the original source of many antibiotics, namely streptomycin, the first antibiotic against tuberculosis. Genomics Sequence alignments of actinomycetotal genomes have led to the identification of three conserved signature indels which are unique to the order Streptomycetales. The enzyme PBGD contains a four-amino-acid insertion which is present in all ''Streptomyces'' species and ''Kitasatospora setae'', but not any other Actinomycetota. Similarly, a one- amino-acid insertion is present in a conserved region of adenylate kinase and is found in all ''Streptomyces'' species and '' K. setae'', but is not found in any other Actinomycetota. Five conserved signature proteins have also been identified which are present in various sequenced ''Streptomyces'' species, but not in ''K. setae''; however, as the complete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomycetaceae
The ''Streptomycetaceae'' are a family of ''Actinomycetota'', making up the monotypic order ''Streptomycetales''. It includes the important genus ''Streptomyces''. This was the original source of many antibiotics, namely streptomycin, the first antibiotic against tuberculosis. Genomics Sequence alignments of actinomycetotal genomes have led to the identification of three conserved signature indels which are unique to the order Streptomycetales. The enzyme PBGD contains a four-amino-acid insertion which is present in all ''Streptomyces'' species and ''Kitasatospora setae'', but not any other Actinomycetota. Similarly, a one- amino-acid insertion is present in a conserved region of adenylate kinase and is found in all ''Streptomyces'' species and '' K. setae'', but is not found in any other Actinomycetota. Five conserved signature proteins have also been identified which are present in various sequenced ''Streptomyces'' species, but not in ''K. setae''; however, as the complete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomyces
''Streptomyces'' is the largest genus of Actinomycetota and the type genus of the family Streptomycetaceae. Over 500 species of ''Streptomyces'' bacteria have been described. As with the other Actinomycetota, streptomycetes are gram-positive, and have genomes with high GC content. Found predominantly in soil and decaying vegetation, most streptomycetes produce spores, and are noted for their distinct "earthy" odor that results from production of a volatile metabolite, geosmin. Streptomycetes are characterised by a complex secondary metabolism. They produce over two-thirds of the clinically useful antibiotics of natural origin (e.g., neomycin, streptomycin, cypemycin, grisemycin, bottromycins and chloramphenicol). The antibiotic streptomycin takes its name directly from ''Streptomyces''. Streptomycetes are infrequent pathogens, though infections in humans, such as mycetoma, can be caused by '' S. somaliensis'' and '' S. sudanensis'', and in plants can be caused by '' S. cavi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-positive
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured when seen through an optical microscope. This is because the thick peptidoglycan layer in the bacterial cell wall retains the stain after it is washed away from the rest of the sample, in the decolorization stage of the test. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization step; alcohol used in this stage degrades the outer membrane of gram-negative cells, making the cell wall more porous and incapable of retaining the crystal violet stain. Their peptidoglycan layer is much thinner and sandwiched between an inner cell membrane and a bacterial outer membrane, causing them to take up the counterstain (saf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pancreatic Lipase
Triglyceride lipases () are a family of lipolytic enzymes that hydrolyse ester linkages of triglycerides. Lipases are widely distributed in animals, plants and prokaryotes. At least three tissue-specific isozymes exist in higher vertebrates, pancreatic, hepatic and gastric/lingual. These lipases are closely related to each other and to lipoprotein lipase (), which hydrolyses triglycerides of chylomicrons and very low density lipoproteins (VLDL). The most conserved region in all these proteins is centred on a serine residue which has been shown to participate, with a histidine and an aspartic acid residue, in a charge relay system. Such a region is also present in lipases of prokaryotic origin and in lecithin-cholesterol acyltransferase () (LCAT), which catalyzes fatty acid transfer between phosphatidylcholine and cholesterol. Human pancreatic lipase ''Pancreatic lipase'', also known as ''pancreatic triacylglycerol lipase'' or ''steapsin'', is an enzyme secreted from the pancre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Inhibitor
An enzyme inhibitor is a molecule that binds to an enzyme and blocks its activity. Enzymes are proteins that speed up chemical reactions necessary for life, in which substrate molecules are converted into products. An enzyme facilitates a specific chemical reaction by binding the substrate to its active site, a specialized area on the enzyme that accelerates the most difficult step of the reaction. An enzyme inhibitor stops ("inhibits") this process, either by binding to the enzyme's active site (thus preventing the substrate itself from binding) or by binding to another site on the enzyme such that the enzyme's catalysis of the reaction is blocked. Enzyme inhibitors may bind reversibly or irreversibly. Irreversible inhibitors form a chemical bond with the enzyme such that the enzyme is inhibited until the chemical bond is broken. By contrast, reversible inhibitors bind non-covalently and may spontaneously leave the enzyme, allowing the enzyme to resume its function. Reve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipstatin
Lipstatin is a potent, irreversible inhibitor of pancreatic lipase. It is a natural product that was first isolated from the actinobacterium ''Streptomyces toxytricini''. The popular antiobesity drug orlistat (trade names Xenical and alli) is a saturated derivative of lipstatin. Biosynthesis Lipstatin is composed of a 2-hexyl-3,5-dihydroxy-7,10-hexadecadienoic-β-lactone 22 carbon backbone from fatty acid synthesis pathway and an ''N''-formyl-L-leucine group ester linked to the 5-hydroxyl group of the back bone. The composts of the lipstatin are ultimately from linoleic acid, octanoic acid, and L-leucine. The 22 carbon β-lactone moiety is derived from Claisen condensation between 3-hydroxytetradeca-5,8-dienyl-CoA derived from linoleic acid and hexyl-malonyl-ACP derived from octanoic acid. Linoleic acid is first attached to CoA through some acyl-CoA synthetase homologue synthesized by lipstatin biosynthetic operons (''Lst'') and goes through two β-oxidation to hydroxytet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
