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Bacterial Cellulose
Bacterial cellulose is an organic compound with the formula produced by certain types of bacteria. While cellulose is a basic structural material of most plants, it is also produced by bacteria, principally of the genera ''Acetobacter'', Sarcina (genus), ''Sarcina ventriculi'' and ''Agrobacterium''. Bacterial, or microbial, cellulose has different properties from plant cellulose and is characterized by high purity, strength, moldability and increased water holding ability. In natural habitats, the majority of bacteria synthesize extracellular polysaccharides, such as cellulose, which form protective envelopes around the cells. While bacterial cellulose is produced in nature, many methods are currently being investigated to enhance cellulose growth from cultures in laboratories as a large-scale process. By controlling synthesis methods, the resulting microbial cellulose can be tailored to have specific desirable properties. For example, attention has been given to the bacteria ''Koma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using energy from sunlight, where it is used to make cellulose in cell walls, the most abundant carbohydrate in the world. In energy metabolism, glucose is the most important source of energy in all organisms. Glucose for metabolism is stored as a polymer, in plants mainly as starch and amylopectin, and in animals as glycogen. Glucose circulates in the blood of animals as blood sugar. The naturally occurring form of glucose is -glucose, while -glucose is produced synthetically in comparatively small amounts and is less biologically active. Glucose is a monosaccharide containing six carbon atoms and an aldehyde group, and is therefore an aldohexose. The glucose molecule can exist in an open-chain (acyclic) as well as ring (cyclic) form. Gluco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexoses
In chemistry, a hexose is a monosaccharide (simple sugar) with six carbon atoms. The chemical formula for all hexoses is C6H12O6, and their molecular weight is 180.156 g/mol. Hexoses exist in two forms, open-chain or cyclic, that easily convert into each other in aqueous solutions. The open-chain form of a hexose, which usually is favored in solutions, has the general structure H–(CHOH)''n''−1–C(=O)–(CHOH)4−''n''–H, where ''n'' is 1, 2, or 3. Namely, five of the carbons have one hydroxyl functional group (–OH) each, connected by a single bond, and one has an oxo group (=O), forming a carbonyl group (C=O). The remaining bonds of the carbon atoms are satisfied by seven hydrogen atoms. The carbons are commonly numbered 1 to 6 starting at the end closest to the carbonyl. Hexoses are extremely important in biochemistry, both as isolated molecules (such as glucose and fructose) and as building blocks of other compounds such as starch, cellulose, and glycosides. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellulose Synthase (UDP-forming)
The UDP-forming form of cellulose synthase () is the main enzyme that produces cellulose. Systematically, it is known as ''UDP-glucose:(1→4)-β-D-glucan 4-β-D-glucosyltransferase'' in enzymology. It catalyzes the chemical reaction: : UDP-glucose + 1→4)-β-D-glucosylsub>n = UDP + 1→4)-β-D-glucosylsub>n+1 A similar enzyme utilizes GDP-glucose, cellulose synthase (GDP-forming) ( EC 2.4.1.29). This family of enzymes is found in bacteria and plants alike. Plant members are usually known as ''CesA'' (cellulose synthase) or the tentative ''CslA'' (cellulose synthase-like), while bacterial members may additionally be known as ''BcsA'' (bacterial cellulose synthase) or ''CelA'' (simply "cellulose"). Plants acquired ''CesA'' from the endosymbiosis event that produced the chloroplast. This family belongs to glucosyltransferase family 2 (GT2). Glycosyltransferases are involved in the biosynthesis and hydrolysis of the bulk of earth's biomass. There are known to be about seve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unhydrolysable Glucose Polymers
A glucan is a polysaccharide derived from D-glucose, linked by glycosidic bonds. Glucans are noted in two forms: alpha glucans and beta glucans. Many beta-glucans are medically important. They represent a drug target for antifungal medications of the echinocandin class. Types The following are glucans (The α- and β- and numbers clarify the type of O-glycosidic bond and the specific carbons involved): Alpha * dextran, α-1,6-glucan with α-1,3-branches * floridean starch, α-1,4- and α-1,6-glucan * glycogen, α-1,4- and α-1,6-glucan * pullulan, α-1,4- and α-1,6-glucan * starch, a mixture of amylose and amylopectin, both α-1,4- and α-1,6-glucans Beta * cellulose, β-1,4-glucan * chrysolaminarin, β-1,3-glucan * curdlan, β-1,3-glucan * laminarin, β-1,3- and β-1,6-glucan * lentinan, a strictly purified β-1,6:β-1,3-glucan from ''Lentinus edodes'' * lichenin, β-1,3- and β-1,4-glucan * oat beta-glucan, β-1,3- and β-1,4-glucan * pleuran, β-1,3- and β-1,6- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uridine Diphosphoglucose
Uridine diphosphate glucose (uracil-diphosphate glucose, UDP-glucose) is a nucleotide sugar. It is involved in glycosyltransferase reactions in metabolism. Functions UDP-glucose is used in nucleotide sugar metabolism as an activated form of glucose, a substrate for enzymes called glucosyltransferases. UDP-glucose is a precursor of glycogen and can be converted into UDP-galactose and UDP-glucuronic acid, which can then be used as substrates by the enzymes that make polysaccharides containing galactose and glucuronic acid. UDP-glucose can also be used as a precursor of sucrose, lipopolysaccharides and glycosphingolipids. Components UDP-glucose consists of the pyrophosphate group, ribose, glucose, and uracil. See also * DNA * Nucleoside * Nucleotide * Oligonucleotide * RNA * TDP-glucose * Uracil * Uridine diphosphate Uridine diphosphate, abbreviated UDP, is a nucleotide diphosphate. It is an ester of pyrophosphoric acid with the nucleoside uridine. UDP consists of the pyro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
