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Fucose
Fucose is a hexose deoxy sugar with the chemical formula C6H12O5. It is found on ''N''-linked glycans on the mammalian, insect and plant cell surface. Fucose is the fundamental sub-unit of the seaweed polysaccharide fucoidan. The α(1→3) linked core of fucoidan is a suspected carbohydrate antigen for IgE-mediated allergy. Two structural features distinguish fucose from other six-carbon sugars present in mammals: the lack of a hydroxyl group on the carbon at the 6-position (C-6) (thereby making it a deoxy sugar) and the L -configuration. It is equivalent to 6-deoxy--galactose. In the fucose-containing glycan structures, fucosylated glycans, fucose can exist as a terminal modification or serve as an attachment point for adding other sugars. In human ''N''-linked glycans, fucose is most commonly linked α-1,6 to the reducing terminal β-''N''-acetylglucosamine. However, fucose at the non-reducing termini linked α-1,2 to galactose forms the H antigen, the substructure o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fucoidan
Fucoidan is a long chain sulfated polysaccharide found in various species of brown algae. Commercially available fucoidan is commonly extracted from the seaweed species ''Fucus vesiculosus'' (Wrack (seaweed), wracks), ''Cladosiphon okamuranus'', ''Laminaria japonica'' (''kombu'', sugar kelp) and ''Undaria pinnatifida'' (''wakame''). Variant forms of fucoidan have also been found in animal species, including the sea cucumber. Fucoidan occurs in the cell walls of the seaweed plant and serves to protect it from external stresses. The same protective benefits that are of value to the seaweed plant have also found to be of potential benefit for both human and animal health. Fucoidan extracts are utilised in a range of therapeutic health care preparations, being incorporated as high value ingredients in nutritional, medical device, skincare and dermatological products. The bioactivity of fucoidan extracts is largely determined by the fucoidan extraction method and the seaweed species fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fucosylation
Fucosylation is the process of adding fucose sugar units to a molecule. It is a type of glycosylation. It is important clinically, and high levels of fucosylation have been reported in cancer. In cancer and inflammation there are significant changes in the expression of fucosylated molecules. Therefore, antibodies and lectins that are able to recognize cancer associated fucosylated oligosaccharides have been used as tumor markers in oncology. It is performed by fucosyltransferase enzymes. Fucosylation has been observed in vertebrates, invertebrates, plants, bacteria, and fungi. It has a role in cellular adhesion and immune regulation. Fucosylation inhibition applications are being explored for a range of clinical application including some associated with sickle cell disease, rheumatoid arthritis, tumor inhibition, and chemotherapy improvements. Recent studies on melanoma patient specimens indicated that melanoma fucosylation and fucosylated HLA-DRB1 are associated with anti-p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FUT8
Alpha-(1,6)-fucosyltransferase is an enzyme that in humans is encoded by the ''FUT8'' gene. This enzyme belongs to the family of fucosyltransferases. The product of this gene catalyzes the transfer of fucose from GDP-fucose to N-linked type complex glycopeptides. This enzyme is distinct from other fucosyltransferases which catalyze alpha1-2, alpha1-3, and alpha1-4 fucose addition. The expression of this gene may contribute to the malignancy of cancer cells and to their invasive and metastatic capabilities. Alternatively spliced variants encoding different isoforms have been identified. Kyowa Hakko Kirin is a Japanese pharmaceutical and biotechnology company under the Kirin Holdings, and is among the 40 largest in the world by revenue. The company is headquartered in Chiyoda-ku, Tokyo and is a member of the Nikkei 225 stock index. History On ...'s "Potelligent" platform uses a CHO cell line in which ''FUT8'' has been knocked out to make afucosylated monoclonal antibodies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbohydrate
A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' may differ). This formula does not imply direct covalent bonding between hydrogen and oxygen atoms; for example, in , hydrogen is covalently bonded to carbon, not oxygen. While the 2:1 hydrogen-to-oxygen ratio is characteristic of many carbohydrates, exceptions exist. For instance, uronic acids and deoxy-sugars like fucose deviate from this precise stoichiometric definition. Conversely, some compounds conforming to this definition, such as formaldehyde and acetic acid, are not classified as carbohydrates. The term is predominantly used in biochemistry, functioning as a synonym for saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-linked Glycan
The terms glycans and polysaccharides are defined by IUPAC as synonyms meaning "compounds consisting of a large number of monosaccharides linked glycosidically". However, in practice the term glycan may also be used to refer to the carbohydrate portion of a glycoconjugate, such as a glycoprotein, glycolipid, or a proteoglycan, even if the carbohydrate is only an oligosaccharide. Glycans usually consist solely of O-glycosidic linkages of monosaccharides. For example, cellulose is a glycan (or, to be more specific, a glucan) composed of β-1,4-linked D-glucose, and chitin is a glycan composed of β-1,4-linked ''N''-acetyl-D-glucosamine. Glycans can be homo- or heteropolymers of monosaccharide residues, and can be linear or branched. Interactions with proteins Glycans can be found attached to proteins as in glycoproteins and proteoglycans. In general, they are found on the exterior surface of cells. ''O''- and ''N''-linked glycans are very common in eukaryotes but may also be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afucosylated Monoclonal Antibodies
Afucosylated monoclonal antibodies are monoclonal antibodies engineered so that the oligosaccharides in the Fc region of the antibody do not have any fucose sugar units. When antibodies are afucosylated, antibody-dependent cellular cytotoxicity (ADCC) is increased. Background Most approved monoclonal antibodies are of the IgG1 isotype, where two N-linked biantennary complex-type oligosaccharides are bound to the Fc region. The Fc region exercises the effector function of ADCC through its interaction with leukocyte receptors of the FcγR family. ADCC is important in the efficacy of cancer antibodies, but with many approved cancer antibodies there is less ADCC than could be desired due to nonspecific IgG competing with the drugs for binding to FcγIIIa on natural killer cells. Afucosylated monoclonal antibodies overcome this problem through improved FcγIIIa binding. Approaches The Swiss company GlycArt Biotechnology developed a system using CHO cells, where the cells were engin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexose
In chemistry, a hexose is a monosaccharide (simple sugar) with six carbon atoms. The chemical formula for all hexoses is , 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 , where ''n'' is 1, 2, 3, 4, 5. Namely, five of the carbons have one hydroxyl functional group () each, connected by a single bond, and one has an oxo group (), forming a carbonyl group (). 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. Hexoses can form dihexose (like sucrose) by a condensation re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fc Receptor
In immunology, an Fc receptor is a protein found on the surface of certain cells – including, among others, B lymphocytes, follicular dendritic cells, natural killer cells, macrophages, neutrophils, eosinophils, basophils, human platelets, and mast cells – that contribute to the protective functions of the immune system. Its name is derived from its binding specificity for a part of an antibody known as the Fc (fragment crystallizable) region. Fc receptors bind to antibodies that are attached to infected cells or invading pathogens. Their activity stimulates phagocytic or cytotoxic cells to destroy microbes, or infected cells by antibody-mediated phagocytosis or antibody-dependent cell-mediated cytotoxicity. Some viruses such as flaviviruses use Fc receptors to help them infect cells, by a mechanism known as antibody-dependent enhancement of infection. Classes There are several different types of Fc receptors (abbreviated FcR), which are classified based on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deoxy Sugar
Deoxy sugars are sugars that have had a hydroxyl group replaced with a hydrogen atom. Examples include: * Deoxyribose, or 2-deoxy-D-ribose, a constituent of DNA * Fucose, or 6-deoxy-L-galactose, main component of fucoidan of brown algae, and present in N-linked glycans * Fuculose, or 6-deoxy-L- tagatose, one of the important components of avian influenza virus particles * Rhamnose, or 6-deoxy-L-mannose, present in plant glycosides In ''Escherichia coli'' bacteria, deoxyribose sugars are synthesized via two different pathways - one pathway involves aldol condensation, whereas the other pathway is conversion of a ribose sugar into a deoxyribose sugar by means of changes on the nucleotide or nucleoside level. Deoxyribose is synthesized through the reduction of ribose. Deoxyribose is derived from the same precursor as ribose being that the reduction of the sugar with the extra hydroxyl group results in the deoxy-sugar, which has its hydroxyl group replaced with a hydrogen atom. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galactose
Galactose (, ''wikt:galacto-, galacto-'' + ''wikt:-ose#Suffix 2, -ose'', ), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweetness, sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epimer of glucose. A galactose molecule linked with a glucose molecule forms a lactose molecule. Galactan is a polymeric form of galactose found in hemicellulose, and forming the core of the galactans, a class of natural polymeric carbohydrates. D-Galactose is also known as brain sugar since it is a component of glycoproteins (oligosaccharide-protein compounds) found in Nerve tissue, nerve tissue. Etymology The word ''galactose'' was coined by Charles Weissman in the mid-19th century and is derived from Greek language, Greek , , and the generic chemical suffix for sugars ''-ose''. The etymology is comparable to that of the word ''lactose'' in that both contain roots meaning "milk sugar". Lactose is a disaccharide of galactose plus glucose. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysosome
A lysosome () is a membrane-bound organelle that is found in all mammalian cells, with the exception of red blood cells (erythrocytes). There are normally hundreds of lysosomes in the cytosol, where they function as the cell’s degradation center. Their primary responsibility is catabolic degradation of proteins, polysaccharides and lipids into their respective building-block molecules: amino acids, monosaccharides, and free fatty acids. The breakdown is done by various enzymes, for example proteases, glycosidases and lipases. With an acidic lumen limited by a single-bilayer lipid membrane, the lysosome holds an environment isolated from the rest of the cell. The lower pH creates optimal conditions for the over 60 different Hydrolase, hydrolases inside. Lysosomes receive extracellular particles through endocytosis, and intracellular components through autophagy. They can also fuse with the plasma membrane and secrete their contents, a process called lysosomal exocytosis. After ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Killer Cell
Natural killer cells, also known as NK cells, are a type of cytotoxic lymphocyte critical to the innate immune system. They are a kind of large granular lymphocytes (LGL), and belong to the rapidly expanding family of known innate lymphoid cells (ILC) and represent 5–20% of all circulating lymphocytes in humans. The role of NK cells is analogous to that of cytotoxic T cells in the vertebrate adaptive immune response. NK cells provide rapid responses to virus-infected cells, stressed cells, tumor cells, and other intracellular pathogens based on signals from several activating and inhibitory receptors. Most immune cells detect the antigen presented on MHC class I, major histocompatibility complex I (MHC-I) on infected cell surfaces, but NK cells can recognize and kill stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction. They were named "natural killers" because of the notion that they do not require activation to kill cells that are m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
