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Apiose
Apiose is a branched-chain sugar found as residues in galacturonans-type pectins; that occurs in parsley and many other plants. Apiose is a component of cell wall polysaccharides. Apiose 1-reductase uses D-apiitol and NAD+ to produce apiitol-apiose, NADH Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an aden ..., and H+. Flavone apiosyltransferase uses UDP-apiose and 5,7,4'-trihydroxyflavone 7-''O''-β-D-glucoside to produce UDP, 5,7,4'-trihydroxyflavone (apigenin), and 7-O-β-D-apiosyl-(1->2)-β-apiitol-glucoside. References External links {{wiktionary inline Aldopentoses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar
Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides or double sugars, are molecules made of two bonded monosaccharides; common examples are sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (two molecules of glucose). White sugar is a refined form of sucrose. In the body, compound sugars are hydrolysed into simple sugars. Longer chains of monosaccharides (>2) are not regarded as sugars, and are called oligosaccharides or polysaccharides. Starch is a glucose polymer found in plants, the most abundant source of energy in human food. Some other chemical substances, such as glycerol and sugar alcohols, may have a sweet taste, but are not classified as sugar. Sugars are found in the tissues of most plants. Honey and fruits are abundant natural sources of simple sugars. Suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galacturonan
-Galacturonic acid is a sugar acid, an oxidized form of -galactose. It is the main component of pectin, in which it exists as the polymer polygalacturonic acid.Debra Mohnen "Pectin structure and biosynthesis" Current Opinion in Plant Biology 2008, 11:266–277. . In its open form, it has an aldehyde group at C1 and a carboxylic acid group at C6. Other oxidized forms of -galactose are -galactonic acid (carboxylic group at C1) and ''meso''-galactaric acid (mucic acid) (carboxylic groups at C1 and C6). It is also a uronic acid or hexuronic acid. Naturally occurring uronic acids are -glucuronic acid, -galacturonic acid, -iduronic acid and -mannuronic acid Mannuronic acid is a uronic acid monosaccharide that can be derived from mannose. Along with -guluronic acid, -mannuronic acid is a component of alginic acid, a polysaccharide found predominantly in brown algae Brown algae (singular: alga), com .... References {{DEFAULTSORT:Galacturonic acid, D- Uronic acids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pectin
Pectin ( grc, πηκτικός ': "congealed" and "curdled") is a heteropolysaccharide, a structural acid contained in the primary lamella, in the middle lamella, and in the cell walls of terrestrial plants. The principal, chemical component of pectin is galacturonic acid (a sugar acid derived from galactose) which was isolated and described by Henri Braconnot in 1825. Commercially produced pectin is a white-to-light-brown powder, produced from citrus fruits for use as an edible gelling agent, especially in jams and jellies, dessert fillings, medications, and sweets; and as a chemical stabiliser in fruit juices and milk drinks, and as a source of dietary fiber. Biology Pectin is composed of complex polysaccharides that are present in the primary cell walls of a plant, and are abundant in the green parts of terrestrial plants. Pectin is the principal component of the middle lamella, where it binds cells. Pectin is deposited by exocytosis into the cell wall via vesicles produc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parsley
Parsley, or garden parsley (''Petroselinum crispum'') is a species of flowering plant in the family Apiaceae that is native to the central and eastern Mediterranean region (Sardinia, Lebanon, Israel, Cyprus, Turkey, southern Italy, Greece, Portugal, Spain, Malta, Morocco, Algeria, and Tunisia), but has been naturalized elsewhere in Europe, and is widely cultivated as a herb, and a vegetable. Parsley is widely used in European, Middle Eastern, and American cuisine. Curly leaf parsley is often used as a garnish. In central Europe, eastern Europe, and southern Europe, as well as in western Asia, many dishes are served with fresh green chopped parsley sprinkled on top. Flat leaf parsley is similar, but it is easier to cultivate, some say it has a stronger flavor. Root parsley is very common in central, eastern, and southern European cuisines, where it is used as a snack or a vegetable in many soups, stews, and casseroles. It is believed to have been originally grown in Sardinia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant
Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclude the fungi and some algae, as well as the prokaryotes (the archaea and bacteria). By one definition, plants form the clade Viridiplantae (Latin name for "green plants") which is sister of the Glaucophyta, and consists of the green algae and Embryophyta (land plants). The latter includes the flowering plants, conifers and other gymnosperms, ferns and their allies, hornworts, liverworts, and mosses. Most plants are multicellular organisms. Green plants obtain most of their energy from sunlight via photosynthesis by primary chloroplasts that are derived from endosymbiosis with cyanobacteria. Their chloroplasts contain chlorophylls a and b, which gives them their green color. Some plants are parasitic or mycotrophic and have lost the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Wall
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mechanism. Cell walls are absent in many eukaryotes, including animals, but are present in some other ones like fungi, algae and plants, and in most prokaryotes (except mollicute bacteria). A major function is to act as pressure vessels, preventing over-expansion of the cell when water enters. The composition of cell walls varies between taxonomic group and species and may depend on cell type and developmental stage. The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicelluloses and pectin. Often, other polymers such as lignin, suberin or cutin are anchored to or embedded in plant cell walls. Algae possess cell walls made of glycoproteins and polysaccharides such as carrageenan and agar that are absent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysaccharides
Polysaccharides (), or polycarbohydrates, are the most abundant carbohydrates found in food. They are long chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with water (hydrolysis) using amylase enzymes as catalyst, which produces constituent sugars (monosaccharides, or oligosaccharides). They range in structure from linear to highly branched. Examples include storage polysaccharides such as starch, glycogen and galactogen and structural polysaccharides such as cellulose and chitin. Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit. Depending on the structure, these macromolecules can have distinct properties from their monosaccharide building blocks. They may be amorphous or even insoluble in water. When all the monosaccharides in a polysaccharide are the same type, the polysaccharide is called a homopolysaccharide or homoglycan, but when more t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apiose 1-reductase
In enzymology, an apiose 1-reductase () is an enzyme that catalyzes the chemical reaction :D-apiitol + NAD+ \rightleftharpoons D-apiose + NADH + H+ Thus, the two substrates of this enzyme are D-apiitol and NAD+, whereas its 3 products are D-apiose, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is D-apiitol:NAD+ 1-oxidoreductase. Other names in common use include D-apiose reductase, and D-apiitol reductase. References * * EC 1.1.1 NADH-dependent enzymes Enzymes of unknown structure {{1.1.1-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicotinamide Adenine Dinucleotide
Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine nucleobase and the other nicotinamide. NAD exists in two forms: an oxidized and reduced form, abbreviated as NAD and NADH (H for hydrogen), respectively. In metabolism, nicotinamide adenine dinucleotide is involved in redox reactions, carrying electrons from one reaction to another. The cofactor is, therefore, found in two forms in cells: NAD is an oxidizing agent – it accepts electrons from other molecules and becomes reduced. This reaction, also with H+, forms NADH, which can then be used as a reducing agent to donate electrons. These electron transfer reactions are the main function of NAD. However, it is also used in other cellular processes, most notably as a substrate of enzymes in adding or removing chemical groups to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Ion
A hydrogen ion is created when a hydrogen atom loses or gains an electron. A positively charged hydrogen ion (or proton) can readily combine with other particles and therefore is only seen isolated when it is in a gaseous state or a nearly particle-free space. Due to its extremely high charge density of approximately 2×1010 times that of a sodium ion, the bare hydrogen ion cannot exist freely in solution as it readily hydrates, i.e., bonds quickly. The hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions. Cation (positively charged) A hydrogen atom is made up of a nucleus with charge +1, and a single electron. Therefore, the only positively charged ion possible has charge +1. It is noted H+. Depending on the isotope in question, the hydrogen cation has different names: * Hydron: general name referri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavone Apiosyltransferase
In enzymology, a flavone apiosyltransferase () is an enzyme that catalyzes the chemical reaction :UDP-apiose + 5,7,4'-trihydroxyflavone 7-O-beta-D-glucoside \rightleftharpoons UDP + 5,7,4'-trihydroxyflavone 7-O- 2)-beta-D-glucoside">eta-D-apiosyl-(1->2)-beta-D-glucoside Thus, the two substrates of this enzyme are UDP-apiose and 5,7,4'-trihydroxyflavone 7-O-beta-D-glucoside, whereas its 3 products are UDP, 5,7,4'-trihydroxyflavone (apigenin), and 7-O-[beta-D-apiosyl-(1->2)-beta-D-glucoside">eta-D-apiosyl-(1->2)-beta-D-glucoside.html" ;"title="7-O-[beta-D-apiosyl-(1->2)-beta-D-glucoside">7-O-[beta-D-apiosyl-(1->2)-beta-D-glucoside This enzyme belongs to the family of glycosyltransferases, specifically the pentosyltransferases. The List of enzymes, systematic name of this enzyme class is UDP-apiose:5,4'-dihydroxyflavone 7-O-beta-D-glucoside 2''-O-beta-D-apiofuranosyltransferase. Other names in common use include uridine diphosphoapiose-flavone apiosyltransferase, and UDP-ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
