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Tetrahymanol Synthase
Tetrahymanol synthase (, ''squalene tetrahymanol cyclase'') is an enzyme with systematic name ''squalene hydro-lyase (tetrahymanol forming)''. This enzyme catalyses the following chemical reaction : tetrahymanol Tetrahymanol is a gammacerane-type membrane lipid first found in the marine ciliate ''Tetrahymena, Tetrahymena pyriformis''. It was later found in other ciliates, Fungus, fungi, ferns, and bacteria. After diagenesis, being deposited in sediments t ... \rightleftharpoons squalene + H2O The reaction occurs in the reverse direction. This enzyme is isolated from Tetrahymena protozoans. References External links * {{Portal bar, Biology, border=no EC 4.2.1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Enzymes
This article lists enzymes by their classification in the International Union of Biochemistry and Molecular Biology's Enzyme Commission (EC) numbering system. * List of EC numbers (EC 5) * List of EC numbers (EC 6) :Oxidoreductases (EC 1) (Oxidoreductase) *Dehydrogenase * Luciferase *DMSO reductase :EC 1.1 (act on the CH-OH group of donors) * :EC 1.1.1 (with NAD+ or NADP+ as acceptor) ** Alcohol dehydrogenase (NAD) ** Alcohol dehydrogenase (NADP) **Homoserine dehydrogenase ** Aminopropanol oxidoreductase **Diacetyl reductase **Glycerol dehydrogenase **Propanediol-phosphate dehydrogenase ** glycerol-3-phosphate dehydrogenase (NAD+) ** D-xylulose reductase **L-xylulose reductase **Lactate dehydrogenase **Malate dehydrogenase **Isocitrate dehydrogenase ** HMG-CoA reductase * :EC 1.1.2 (with a cytochrome as acceptor) * :EC 1.1.3 (with oxygen as acceptor) **Glucose oxidase **L-gulonolactone oxidase **Thiamine oxidase **Xanthine oxidase * :EC 1.1.4 (with a disul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalysis
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (chemistry), products, which usually have properties different from the reactants. Reactions often consist of a sequence o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahymanol
Tetrahymanol is a gammacerane-type membrane lipid first found in the marine ciliate ''Tetrahymena pyriformis''. It was later found in other ciliates, fungi, ferns, and bacteria. After being deposited in sediments that compress into sedimentary rocks over millions of years, tetrahymanol is dehydroxylated into gammacerane. Gammacerane has been interpreted as a proxy for ancient water column stratification. Chemistry Structure Tetrahymanol is a pentacyclic triterpenoid molecule. The triterpenoids are a class of molecules found in both bacteria and eukaryotes, which largely make hopanols and sterols, respectively. The structures of these three classes of molecules are shown below. Cholesterol and diploptene are used as model sterol and hopanol structures, respectively. While diploptene and tetrahymanol broadly have similar structures, the fifth ring on tetrahymanol is a cyclohexane rather than a cyclopentane. All three of these molecular classes have structures that lend themse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squalene
Squalene is an organic compound. It is a triterpenoid with the formula C30H50. It is a colourless oil, although impure samples appear yellow. It was originally obtained from shark liver oil (hence its name, as ''Squalus'' is a genus of sharks). All plants and animals produce squalene as a biochemical intermediate to sterol biosynthesis. An estimated 12% of bodily squalene in humans is found in Sebaceous gland, sebum. Squalene has a role in topical skin lubrication and protection. Squalene is a precursor (chemistry), precursor for synthesis of all plant and animal sterols, including cholesterol and steroid hormones in the human body. Squalene is an important ingredient in some vaccine adjuvants: The Novartis and GlaxoSmithKline adjuvants are called MF59 and AS03, respectively. Role in steroid synthesis Squalene is the biochemical precursor to steroids. The squalene conversion begins with oxidation (via squalene monooxygenase) of one of its terminal double bonds, resulting in 2,3- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahymena
''Tetrahymena'', a Unicellular organism, unicellular eukaryote, is a genus of free-living ciliates. The genus Tetrahymena is the most widely studied member of its phylum. It can produce, store and react with different types of hormones. Tetrahymena cells can recognize both related and hostile cells. They can also switch from commensalism, commensalistic to pathogenic modes of survival. They are common in freshwater lakes, ponds, and streams. ''Tetrahymena'' species used as model organisms in biomedical research are ''T. thermophila'' and ''T. pyriformis''. ''T. thermophila'': a model organism in experimental biology As a ciliated protozoan, ''Tetrahymena thermophila'' exhibits nuclear dimorphism: two types of cell Cell nucleus, nuclei. They have a bigger, Somatic cell, non-germline macronucleus and a small, germline micronucleus in each cell at the same time and these two carry out different functions with distinct cytological and biological properties. This unique vers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
