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Wilchek
Meir Wilchek (Hebrew: מאיר אשר וילצ'ק, born 17 October 1935) is an Israeli biochemist. He is a professor at the Weizmann Institute of Science. Early life and education Meir Wilchek was born in Warsaw, Poland, scion of a rabbinical family. During the Holocaust, he escaped from the German-occupied territories to the territories occupied by Russia, and was transferred to Siberia, while his father, who served as a community rabbi in Warsaw, was killed in Flossenbürg concentration camp. He survived, and immigrated to Israel in 1949 with his mother and sister. He graduated with B.Sc. in chemistry from Bar Ilan university and Ph.D. in biochemistry from the Weizmann Institute of Science. Wilchek has published over 400 scientific papers, and consulted various biotech companies. He was also in the party list of Mafdal and Meimad for the Knesset. Scientific contributions Meir Wilchek is known for his research in the field of biorecognition or affinity phenomenon, and its variou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avidin
Avidin is a tetrameric biotin-binding protein produced in the oviducts of birds, reptiles and amphibians and deposited in the whites of their eggs. Dimeric members of the avidin family are also found in some bacteria. In chicken egg white, avidin makes up approximately 0.05% of total protein (approximately 1800 μg per egg). The tetrameric protein contains four identical subunits (homotetramer), each of which can bind to biotin (Vitamin B7, vitamin H) with a high degree of affinity and specificity. The dissociation constant of the avidin-biotin complex is measured to be ''K''D ≈ 10−15 M, making it one of the strongest known non-covalent bonds. In its tetrameric form, avidin is estimated to be 66–69 k Da in size. 10% of the molecular weight is contributed by carbohydrate, composed of four to five mannose and three N-acetylglucosamine residues The carbohydrate moieties of avidin contain at least three unique oligosaccharide structural types that are similar in structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Affinity Chromatography
Affinity chromatography is a method of separating a biomolecule from a mixture, based on a highly specific macromolecular binding interaction between the biomolecule and another substance. The specific type of binding interaction depends on the biomolecule of interest; antigen and antibody, enzyme and substrate, receptor and ligand, or protein and nucleic acid binding interactions are frequently exploited for isolation of various biomolecules. Affinity chromatography is useful for its high selectivity and resolution of separation, compared to other chromatographic methods. Principle Affinity chromatography has the advantage of specific binding interactions between the analyte of interest (normally dissolved in the mobile phase), and a binding partner or ligand (immobilized on the stationary phase). In a typical affinity chromatography experiment, the ligand is attached to a solid, insoluble matrix—usually a polymer such as agarose or polyacrylamide—chemically modified ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Affinity Chromatography
Affinity chromatography is a method of separating a biomolecule from a mixture, based on a highly specific macromolecular binding interaction between the biomolecule and another substance. The specific type of binding interaction depends on the biomolecule of interest; antigen and antibody, enzyme and substrate, receptor and ligand, or protein and nucleic acid binding interactions are frequently exploited for isolation of various biomolecules. Affinity chromatography is useful for its high selectivity and resolution of separation, compared to other chromatographic methods. Principle Affinity chromatography has the advantage of specific binding interactions between the analyte of interest (normally dissolved in the mobile phase), and a binding partner or ligand (immobilized on the stationary phase). In a typical affinity chromatography experiment, the ligand is attached to a solid, insoluble matrix—usually a polymer such as agarose or polyacrylamide—chemically modified ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Förster Resonance Energy Transfer
Förster resonance energy transfer (FRET), fluorescence resonance energy transfer, resonance energy transfer (RET) or electronic energy transfer (EET) is a mechanism describing energy transfer between two light-sensitive molecules ( chromophores). A donor chromophore, initially in its electronic excited state, may transfer energy to an acceptor chromophore through nonradiative dipole–dipole coupling. The efficiency of this energy transfer is inversely proportional to the sixth power of the distance between donor and acceptor, making FRET extremely sensitive to small changes in distance. Measurements of FRET efficiency can be used to determine if two fluorophores are within a certain distance of each other. Such measurements are used as a research tool in fields including biology and chemistry. FRET is analogous to near-field communication, in that the radius of interaction is much smaller than the wavelength of light emitted. In the near-field region, the excited chromophore e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weizmann Institute Of Science
The Weizmann Institute of Science ( he, מכון ויצמן למדע ''Machon Vaitzman LeMada'') is a public research university in Rehovot, Israel, established in 1934, 14 years before the State of Israel. It differs from other Israeli universities in that it offers only postgraduate degrees in the natural and exact sciences. It is a multidisciplinary research center, with around 3,800 scientists, postdoctoral fellows, Ph.D. and M.Sc. students, and scientific, technical, and administrative staff working at the institute. As of 2019, six Nobel laureates and three Turing Award winners have been associated with the Weizmann Institute of Science. History Founded in 1934 by Chaim Weizmann and his first team, among them Benjamin M. Bloch, as the Daniel Sieff Research Institute. Weizmann had offered the post of director to Nobel Prize laureate Fritz Haber, but took over the directorship himself after Haber's death en route to Palestine. Before he became President of the State o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissociation Constant
In chemistry, biochemistry, and pharmacology, a dissociation constant (K_D) is a specific type of equilibrium constant that measures the propensity of a larger object to separate (dissociate) reversibly into smaller components, as when a complex falls apart into its component molecules, or when a salt splits up into its component ions. The dissociation constant is the inverse of the association constant. In the special case of salts, the dissociation constant can also be called an ionization constant. For a general reaction: : A_\mathit B_\mathit \mathit A + \mathit B in which a complex \ce_x \ce_y breaks down into ''x'' A subunits and ''y'' B subunits, the dissociation constant is defined as : K_D = \frac where and ''x'' B''y''are the equilibrium concentrations of A, B, and the complex A''x'' B''y'', respectively. One reason for the popularity of the dissociation constant in biochemistry and pharmacology is that in the frequently encount ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allicin
Allicin is an organosulfur compound obtained from garlic, a species in the family Alliaceae. It was first isolated and studied in the laboratory by Chester J. Cavallito and John Hays Bailey in 1944. When fresh garlic is chopped or crushed, the enzyme alliinase converts alliin into allicin, which is responsible for the aroma of fresh garlic. The allicin generated is unstable and quickly changes into a series of other sulfur-containing compounds such as diallyl disulfide. Allicin is part of a defense mechanism against attacks by pests on the garlic plant. Allicin is an oily, slightly yellow liquid that gives garlic its distinctive odor. It is a thioester of sulfenic acid and is also known as allyl thiosulfinate. Its biological activity can be attributed to both its antioxidant activity and its reaction with thiol-containing proteins. Produced in garlic cells, allicin is released upon disruption, producing a potent aroma when garlic is cut or cooked, and is among the chemicals res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biotin
Biotin (or vitamin B7) is one of the B vitamins. It is involved in a wide range of metabolic processes, both in humans and in other organisms, primarily related to the utilization of fats, carbohydrates, and amino acids. The name ''biotin'', borrowed from the German , derives from the Ancient Greek word (; 'life') and the suffix "-in" (a suffix used in chemistry usually to indicate 'forming'). Chemical description Biotin is classified as a heterocyclic compound, with a sulfur-containing ring fused ureido and tetrahydrothiophene group. A C5-carboxylic acid side chain is appended to one of the rings. The ureido ring, containing the −N−CO−N− group, serves as the carbon dioxide carrier in carboxylation reactions. Biotin is a coenzyme for five carboxylase enzymes, which are involved in the catabolism of amino acids and fatty acids, synthesis of fatty acids, and gluconeogenesis. Biotinylation of histone proteins in nuclear chromatin plays a role in chromatin stability and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all areas of the life sciences are being uncovered and developed through biochemical methodology and research. Voet (2005), p. 3. Biochemistry focuses on understanding the chemical basis which allows biological molecules to give rise to the processes that occur within living cells and between cells,Karp (2009), p. 2. in turn relating greatly to the understanding of tissues and organs, as well as organism structure and function.Miller (2012). p. 62. Biochemistry is closely related to molecular biology, which is the study of the molecular mechanisms of biological phenomena.As ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine
Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form under biological conditions), and a side chain consisting of a hydroxymethyl group, classifying it as a polar amino acid. It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid. It is encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC. Occurrence This compound is one of the naturally occurring proteinogenic amino acids. Only the L-stereoisomer appears naturally in proteins. It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865 by Emil Cramer. Its name is derived from the Latin for silk, ''sericum''. Serine's structure was estab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cysteine
Cysteine (symbol Cys or C; ) is a semiessential proteinogenic amino acid with the formula . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile. When present as a deprotonated catalytic residue, sometimes the symbol Cyz is used. The deprotonated form can generally be described by the symbol Cym as well. The thiol is susceptible to oxidation to give the disulfide derivative cystine, which serves an important structural role in many proteins. In this case, the symbol Cyx is sometimes used. When used as a food additive, it has the E number E920. Cysteine is encoded by the codons UGU and UGC. The sulfur-containing amino acids cysteine and methionine are more easily oxidized than the other amino acids. Structure Like other amino acids (not as a residue of a protein), cysteine exists as a zwitterion. Cysteine has chirality in the older / notation based on homology to - and -glyceraldehyde. In the newer ''R''/''S'' system of designating chi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warsaw
Warsaw ( pl, Warszawa, ), officially the Capital City of Warsaw,, abbreviation: ''m.st. Warszawa'' is the capital and largest city of Poland. The metropolis stands on the River Vistula in east-central Poland, and its population is officially estimated at 1.86 million residents within a greater metropolitan area of 3.1 million residents, which makes Warsaw the 7th most-populous city in the European Union. The city area measures and comprises 18 districts, while the metropolitan area covers . Warsaw is an Alpha global city, a major cultural, political and economic hub, and the country's seat of government. Warsaw traces its origins to a small fishing town in Masovia. The city rose to prominence in the late 16th century, when Sigismund III decided to move the Polish capital and his royal court from Kraków. Warsaw served as the de facto capital of the Polish–Lithuanian Commonwealth until 1795, and subsequently as the seat of Napoleon's Duchy of Warsaw. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
