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Juvabione
Juvabione, historically known as the paper factor, is the methyl ester of todomatuic acid. Both are sesquiterpenes (C15) found in the wood of true firs of the genus ''Abies''. They occur naturally as part of a mixture of sesquiterpenes based upon the bisabolane scaffold. Sesquiterpenes of this family are known as insect juvenile hormone analogues (IJHA) because of their ability to mimic juvenile activity in order to stifle insect reproduction and growth. These compounds play important roles in conifers as the second line of defense against insect induced trauma and fungal pathogens. History In 1965, Karel Sláma and Carroll Williams made a surprising discovery: paper towels made from the wood of the balsam fir (''Abies balsamea'', Fig. 1) released vapors that elicited a potent effect on hemipteran bugs of the Pyrrhocoridae family. They named this substance "the paper factor." It was thought to contain a mixture of JH-mimicking sesquiterpenes, but it wasn't until 1966 that (+)-juv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distinctive functional group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well (e.g. amides), but not according to the IUPAC. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Lactones are cyclic carboxylic esters; naturally occurring lactones are mainly 5- and 6-membered ring lactones. Lactones contribute to the aroma of fruits, butter, cheese, vegetables like celery and other foods. Esters can be formed from oxoacids (e.g. esters of acetic acid, carbonic acid, sulfuric acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myrcene Synthase
The enzyme myrcene synthase (EC 4.2.3.15) catalyzes the chemical reaction :geranyl diphosphate \rightleftharpoons myrcene + diphosphate This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on phosphates. The systematic name of this enzyme class is geranyl-diphosphate diphosphate-lyase (myrcene-forming). This enzyme participates in monoterpenoid biosynthesis Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen funct .... References * EC 4.2.3 Enzymes of unknown structure {{4.2-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoprene
Isoprene, or 2-methyl-1,3-butadiene, is a common volatile organic compound with the formula CH2=C(CH3)−CH=CH2. In its pure form it is a colorless volatile liquid. It is produced by many plants and animals (including humans) and its polymers are the main component of natural rubber. History and etymology Charles Greville Williams, C. G. Williams named the compound in 1860 after obtaining it from the pyrolysis of natural rubber. He correctly deduced the mass shares of carbon and hydrogen (but arrived at an incorrect formula C10H8 because the modern atomic weight of carbon was not adopted until the Karlsruhe Congress held later that year). He did not specify the reasons for the name, but it is hypothesized that it came from "propylene" with which isoprene shares some physical and chemical properties. The first one to observe recombination of isoprene into rubber-like substance was in 1879, and William A. Tilden identified its structure five years later. Natural occurrences Is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Triphosphate
Adenosine triphosphate (ATP) is a nucleoside triphosphate that provides energy to drive and support many processes in living cell (biology), cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all known forms of life, it is often referred to as the "molecular unit of currency" for intracellular energy transfer. When consumed in a Metabolism, metabolic process, ATP converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. It is also a Precursor (chemistry), precursor to DNA and RNA, and is used as a coenzyme. An average adult human processes around 50 kilograms (about 100 mole (unit), moles) daily. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the Polyphosphate, triphosphate. Structure ATP consists of three parts: a sugar, an amine base ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mevalonic Acid
Mevalonic acid (MVA) is a key organic compound in biochemistry; the name is a contraction of dihydroxymethylvalerolactone. The carboxylate anion of mevalonic acid, which is the predominant form in biological environments, is known as ''mevalonate'' and is of major pharmaceutical importance. Drugs like statins (which lower levels of cholesterol) stop the production of mevalonate by inhibiting HMG-CoA reductase. Chemistry Mevalonic acid is very soluble in water and polar organic solvents. It exists in equilibrium with its lactone form, called mevalonolactone, that is formed by internal condensation of its terminal alcohol and carboxylic acid functional groups. Mevalonolactone acts to correct statin linked myopathy and limb girdle muscular disease caused by HMG CoA reductase mutation. Biology Mevalonic acid is a precursor in the biosynthetic pathway known as the mevalonate pathway that produces terpenes and steroids. Mevalonic acid is the primary precursor of isopentenyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMG-CoA
β-Hydroxy β-methylglutaryl-CoA (HMG-CoA), also known as 3-hydroxy-3-methylglutaryl coenzyme A, is an intermediate in the mevalonate pathway, mevalonate and ketogenesis pathways. It is formed from acetyl CoA and acetoacetyl CoA by HMG-CoA synthase. The research of Minor J. Coon and Bimal Kumar Bachhawat in the 1950s at University of Illinois led to its discovery. HMG-CoA is a metabolic intermediate in the metabolism of the branched-chain amino acids, which include leucine, isoleucine, and valine. Its immediate precursors are β-methylglutaconyl-CoA (MG-CoA) and β-hydroxy β-methylbutyryl-CoA (HMB-CoA). HMG-CoA reductase catalyzes the conversion of HMG-CoA to mevalonic acid, a necessary step in the biosynthesis of cholesterol. Biosynthesis Mevalonate pathway Mevalonate synthesis begins with the beta-ketothiolase-catalyzed Claisen condensation of two molecules of acetyl-CoA to produce Acetoacetyl-CoA, acetoacetyl CoA. The following reaction involves the joining of acetyl-C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetoacetyl-CoA
Acetoacetyl CoA is the precursor of HMG-CoA in the mevalonate pathway, which is essential for cholesterol biosynthesis. It also takes a similar role in the ketone bodies synthesis ( ketogenesis) pathway of the liver. In the ketone bodies digestion pathway (in the tissue), it is no longer associated with having HMG-CoA as a product or as a reactant. It is created from acetyl-CoA, a thioester, which reacts with the enolate of a second molecule of acetyl-CoA in a Claisen condensation reaction, and it is acted upon by HMG-CoA synthase to form HMG-CoA. During the metabolism of leucine, this last reaction is reversed. Some individuals may experience Acetoacetyl-CoA deficiency. This deficiency is classified as a disorder ketone body and isoleucine metabolism that can be inherited. Additional mutations include those with the enzymes within pathways related to Acetoacetyl CoA, including Beta-Ketothiolase deficiency and Mitochondrial 3-hydroxy-3-methylglutaryl-CoA Synthase mutation. Add ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation Reaction
In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis. However other molecules can also be lost, such as ammonia, ethanol, acetic acid and hydrogen sulfide. The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation). The reaction may otherwise involve the functional groups of the molecule, and is a versatile class of reactions that can occur in acidic or basic conditions or in the presence of a catalyst. This class of reactions is a vital part of life as it is essential to the formation of peptide bonds between amino acids and to the biosynthesis of fatty acids. Many variations of condensation reactions exist. Common examples include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetyl-CoA
Acetyl-CoA (acetyl coenzyme A) is a molecule that participates in many biochemical reactions in protein, carbohydrate and lipid metabolism. Its main function is to deliver the acetyl group to the citric acid cycle (Krebs cycle) to be oxidation, oxidized for energy production. Coenzyme A (CoASH or CoA) consists of a cysteamine, β-mercaptoethylamine group linked to pantothenic acid (vitamin B5) through an amide linkage and 3'-phosphorylated ADP. The acetyl group (indicated in blue in the structural diagram on the right) of acetyl-CoA is linked to the sulfhydryl substituent of the β-mercaptoethylamine group. This thioester linkage is a "high energy" bond, which is particularly reactive. Hydrolysis of the thioester bond is exergonic (−31.5 kJ/mol). CoA is acetylated to acetyl-CoA by the breakdown of carbohydrates through glycolysis and by the breakdown of fatty acids through Beta oxidation, β-oxidation. Acetyl-CoA then enters the citric acid cycle, where the acetyl group is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-bisabolene Synthase
α-Bisabolene synthase (EC 4.2.3.38, bisabolene synthase) is an enzyme with systematic name (2''E'',6''E'')-farnesyl-diphosphate diphosphate-lyase ((''E'')-α-bisabolene-forming). This enzyme catalyses the following chemical reaction: : (2''E'',6''E'')-farnesyl diphosphate \rightleftharpoons (''E'')-α-bisabolene + diphosphate This synthase requires a divalent cation cofactor (Mg2+ or, to a lesser extent, Mn2+) to neutralize the negative charge of the diphosphate In chemistry, pyrophosphates are phosphorus oxyanions that contain two phosphorus atoms in a linkage. A number of pyrophosphate salts exist, such as disodium pyrophosphate () and tetrasodium pyrophosphate (), among others. Often pyrophosphate ... leaving group. References External links * EC 4.2.3 {{4.2-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bisabolene
Bisabolenes are a group of closely related natural chemical compounds which are classified as sesquiterpenes. Bisabolenes are produced from farnesyl pyrophosphate (FPP) and are present in the essential oils of bisabol, and of a wide variety of other plants including cubeb, lemon, and oregano. Various derivates also function as pheromones in different insects, such as stink bugs and fruit flies. Bisabolenes are produced by several fungi, though their biological role in that group of organisms remains unclear. Three isomers are known, α-, β-, and γ-bisabolene, which differ by the positions of the double bonds. Uses Bisabolenes are intermediates in the biosynthesis of many other natural chemical compounds, including hernandulcin, a natural sweetener. β-Bisabolene has a balsamic odor and is approved in Europe as a food additive. Bisabolene has been identified as a biologically producible precursor to a diesel fuel alternative and/or cold weather additive bisabol''ane''. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthase
In biochemistry, a synthase is an enzyme that catalyses a synthesis process. Note that, originally, biochemical nomenclature distinguished synthetases and synthases. Under the original definition, synthases do not use energy from nucleoside triphosphates (such as ATP, GTP, CTP, TTP, and UTP), whereas synthetases do use nucleoside triphosphates. However, the Joint Commission on Biochemical Nomenclature (JCBN) dictates that 'synthase' can be used with any enzyme that catalyzes synthesis (whether or not it uses nucleoside triphosphates), whereas 'synthetase' is to be used synonymously with ' ligase'. Examples * ATP synthase * Citrate synthase * Tryptophan synthase * Pseudouridine synthase * Fatty acid synthase Fatty acid synthase (FAS) is an enzyme that in humans is encoded by the ''FASN'' gene. Fatty acid synthase is a multi-enzyme protein that catalyzes fatty acid synthesis. It is not a single enzyme but a whole enzymatic system composed of two ide ... * Cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
