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Aequorin
Aequorin is a calcium-activated photoprotein isolated from the hydrozoan ''Aequorea victoria''. Its bioluminescence was studied decades before the protein was isolated from the animal by Osamu Shimomura in 1962. In the animal, the protein occurs together with the green fluorescent protein to produce green light by resonant energy transfer, while aequorin by itself generates blue light. Discussions of "jellyfish DNA" that can make "glowing" animals often refer to transgenic animals that express the green fluorescent protein, not aequorin, although both originally derive from the same animal. Apoaequorin, the protein portion of aequorin, is an ingredient in the dietary supplement Prevagen. The US Federal Trade Commission (FTC) has charged the maker with false advertising for its memory improvement claims. Discovery Work on aequorin began with E. Newton Harvey in 1921. Though Harvey was unable to demonstrate a classical luciferase-luciferin reaction, he showed that water could ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Fluorescent Protein
The green fluorescent protein (GFP) is a protein that exhibits bright green fluorescence when exposed to light in the blue to ultraviolet range. The label ''GFP'' traditionally refers to the protein first isolated from the jellyfish ''Aequorea victoria'' and is sometimes called ''avGFP''. However, GFPs have been found in other organisms including corals, sea anemones, zoanithids, copepods and lancelets. The GFP from ''A. victoria'' has a major excitation peak at a wavelength of 395 nm and a minor one at 475 nm. Its emission peak is at 509 nm, which is in the lower green portion of the visible spectrum. The fluorescence quantum yield (QY) of GFP is 0.79. The GFP from the sea pansy (''Renilla reniformis'') has a single major excitation peak at 498 nm. GFP makes for an excellent tool in many forms of biology due to its ability to form an internal chromophore without requiring any accessory cofactors, gene products, or enzymes / substrates other than mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioluminescence
Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus ''Vibrio''; in others, it is autogenic, produced by the animals themselves. In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin. In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aequorea Victoria
''Aequorea victoria'', also sometimes called the crystal jelly, is a bioluminescent hydrozoan jellyfish, or hydromedusa, that is found off the west coast of North America. The species is best known as the source of two proteins involved in bioluminescence, aequorin, a photoprotein, and green fluorescent protein (GFP). Their discoverers, Osamu Shimomura and colleagues, won the 2008 Nobel Prize in Chemistry for their work on GFP. Description Almost entirely transparent and colorless, and sometimes difficult to resolve, ''Aequorea victoria'' possess a highly contractile mouth and manubrium at the center of up to 100 radial canals that extend to the bell margin. The bell margin is surrounded by uneven tentacles, up to 150 of them in fully-grown specimens. The tentacles possess nematocysts that aid in prey capture, although they have no effect on humans. Specimens larger than 3 cm usually possess gonads for sexual reproduction, which run most of the length of the radial canals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoprotein
Photoproteins are a type of enzyme, made of protein, from bioluminescent organisms. They add to the function of the luciferins whose usual light-producing reaction is catalyzed by the enzyme luciferase. History The term photoprotein was first used to describe the unusual chemistry of the luminescent system of ''Chaetopterus'' (a marine Polychaete worm). This was meant to distinguish them from other light-producing proteins because these do not exhibit the usual luciferin-luciferase reaction. Reaction kinetics Photoproteins do not display typical enzyme kinetics as seen in luciferases. Instead, when mixed with luciferin, they display luminescence proportional to the amount of the photoprotein. For example, the photoprotein aequorin produces a flash of light when luciferin and calcium are added, rather than the prolonged glow that is seen for luciferases when luciferin is added. In this respect, it may appear that photoproteins are not enzymes, when in fact they do catalyze their bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luciferin
Luciferin (from the Latin ''lucifer'', "light-bearer") is a generic term for the light-emitting compound found in organisms that generate bioluminescence. Luciferins typically undergo an enzyme-catalyzed reaction with molecular oxygen. The resulting transformation, which usually involves splitting off a molecular fragment, produces an excited state intermediate that emits light upon decaying to its ground state. The term may refer to molecules that are substrates for both luciferases and photoproteins. Types Luciferins are a class of small-molecule substrates that react with oxygen in the presence of a luciferase (an enzyme) to release energy in the form of light. It is not known just how many types of luciferins there are, but some of the better-studied compounds are listed below. Because of the chemical diversity of luciferins, there is no clear unifying mechanism of action, except that all require molecular oxygen, The variety of luciferins and luciferases, their diver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coelenterazine
Coelenterazine is a luciferin, a molecule that emits light after reaction with oxygen, found in many aquatic organisms across eight phyla. It is the substrate of many luciferases such as ''Renilla reniformis'' luciferase (Rluc), ''Gaussia'' luciferase (Gluc), and photoproteins, including aequorin, and obelin. All these proteins catalyze the oxidation of this substance, a reaction catalogued EC 1.13.12.5. History Coelenterazine was simultaneously isolated and characterized by two groups studying the luminescent organisms sea pansy (''Renilla reniformis'') and the cnidarian ''Aequorea victoria'', respectively. Both groups independently discovered that the same compound was used in both luminescent systems. The molecule was named after the now-obsolete phylum coelenterata. Likewise, the two main metabolites – coelenteramide and coelenteramine – were named after their respective functional groups. While coelenterazine was first discovered in ''Aequorea victoria'', it was lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osamu Shimomura
was a Japanese organic chemist and marine biologist, and Professor Emeritus at Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts and Boston University School of Medicine. He was awarded the Nobel Prize in Chemistry in 2008 for the discovery and development of green fluorescent protein (GFP) with two American scientists: Martin Chalfie of Columbia University and Roger Tsien of the University of California-San Diego. Biography Born in Fukuchiyama, Kyoto in 1928, Shimomura was brought up in Manchukuo (Manchuria, China) and Osaka, Japan while his father served as an officer in the Imperial Japanese Army. Later, his family moved to Isahaya, Nagasaki, 25 km from the epicenter of the August 1945 atomic bombing of the city. He recalled hearing, as a 16-year-old boy, the bomber plane ''Bockscar'' before the atom bomb exploded.Nobelprize.org Nobel laureate lecture.December 8, 2008. The explosion flash blinded Shimomura for about thirty seconds, and he was later dr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfred Nobel was a Swedish chemist, engineer, and industrialist most famously known for the invention of dynamite. He died in 1896. In his will, he bequeathed all of his "remaining realisable assets" to be used to establish five prizes which became known as "Nobel Prizes." Nobel Prizes were first awarded in 1901. Nobel Prizes are awarded in the fields of Physics, Chemistry, Physiology or Medicine, Literature, and Peace (Nobel characterized the Peace Prize as "to the person who has done the most or best to advance fellowship among nations, the abolition or reduction of standing armies, and the establishment and promotion of peace congresses"). In 1968, Sveriges Riksbank (Sweden's central bank) funded the establishment of the Prize in Economi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossilised remnants of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name derives from Latin ''calx'' "lime", which was obtained from heating limestone. Some calcium compounds were known to the ancients, though their chemistry was unknown until the seventeenth century. Pure calcium was isolated in 1808 via electrolysis of its oxide by Humphry Davy, who named the element. Calcium compounds are widely used in many industries: in foods and pharma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martin Chalfie
Martin Lee Chalfie (born January 15, 1947) is an American scientist. He is University Professor at Columbia University. He shared the 2008 Nobel Prize in Chemistry along with Osamu Shimomura and Roger Y. Tsien "for the discovery and development of the green fluorescent protein, GFP". He holds a PhD in neurobiology from Harvard University. Education and early life Chalfie grew up in Chicago, Illinois, son of the guitarist Eli Chalfie (1910–1996) and owner of an apparel store Vivian Chalfie (née Friedlen, 1913–2005). His maternal grandfather, Meyer L. Friedlen, immigrated to Chicago from Moscow at an early age; his paternal grandparents, Benjamin and Esther Chalfie, came to Cincinnati from Brest-Litovsk. He matriculated at Harvard University in 1965, intending to be a math major, but he switched to biochemistry because it combined his interests in chemistry, math, and biology. He spent the summer after his junior year working in the laboratory of Klaus Weber at Harvard, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roger Tsien
Roger Yonchien Tsien (pronounced , "'' CHEN''"'';'' February 1, 1952 – August 24, 2016) was an American biochemist. He was a professor of chemistry and biochemistry at the University of California, San Diego and was awarded the Nobel Prize in Chemistry for his discovery and development of the green fluorescent protein, in collaboration with organic chemist Osamu Shimomura and neurobiologist Martin Chalfie. Tsien was also a pioneer of calcium imaging. Early life Tsien was born to a Chinese American family in New York, in 1952. He grew up in Livingston, New Jersey and attended Livingston High School. Tsien traces his family ancestry to Hangzhou, China. His father Hsue-Chu Tsien, an MIT and Shanghai Jiao Tong University alumnus, was a mechanical engineer and had excelled academically, graduating at the top of his university class. Tsien suffered from asthma as a child, and as a result, he was often indoors. He spent hours conducting chemistry experiments in his basemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribbon Diagram
Ribbon diagrams, also known as Richardson diagrams, are three-dimensional space, 3D schematic representations of protein structure and are one of the most common methods of protein depiction used today. The ribbon shows the overall path and organization of the protein backbone in 3D, and serves as a visual framework on which to hang details of the full atomic structure, such as the balls for the oxygen atoms bound to the active site of myoglobin in the adjacent image. Ribbon diagrams are generated by interpolating a smooth curve through the polypeptide backbone. Alpha helix, α-helices are shown as coiled ribbons or thick tubes, Beta strand, β-strands as arrows, and non-repetitive coils or loops as lines or thin tubes. The direction of the Peptide, polypeptide chain is shown locally by the arrows, and may be indicated overall by a colour ramp along the length of the ribbon. Ribbon diagrams are simple yet powerful, expressing the visual basics of a molecular structure (twist, fold ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
