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Bromoperoxidase
Bromide peroxidase (, ''bromoperoxidase'', ''haloperoxidase (ambiguous)'', ''eosinophil peroxidase'') is a family of enzymes with systematic name ''bromide:hydrogen-peroxide oxidoreductase''. These enzymes catalyses the following chemical reaction: : HBr + H2O2 \rightleftharpoons HOBr + H2O The HOBr is a potent brominating agent. The many organobromine compounds observed in marine environments are the products of reaction with this oxidized form of bromine. Bromo peroxidases of red and brown marine algae (''Rhodophyta'' and ''Phaeophyta'') contain vanadate (vanadium bromoperoxidase). Otherwise vanadium is unusual cofactor in biology. By virtue of this family of enzymes, a variety of brominated natural products have been isolated from marine sources. Related chloroperoxidase enzymes effect chlorination. In the nomenclature of haloperoxidase, bromoperoxidases classically are unable to oxidize chloride at all. For example, eosinophil peroxidase appears to prefer bromide ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadium Bromoperoxidase
Vanadium bromoperoxidases are a kind of enzymes called haloperoxidases. Its primary function is to remove hydrogen peroxide which is produced during photosynthesis from in or around the cell. By producing hypobromous acid (HOBr) a secondary reaction with dissolved organic matter, what results is the bromination of organic compounds that are associated with the defense of the organism. These enzymes produce the bulk of natural organobromine compounds in the world. Vanadium bromoperoxidases are one of the few classes of enzymes that requires vanadium. The active site features a vanadium oxide center attached to the protein via one histidine side chain and a collection of hydrogen bonds to the oxide ligands. Occurrence and function Vanadium bromoperoxidases have been found in bacteria, fungi, marine macro algae (seaweeds), and marine microalgae (diatoms) which produce brominated organic compounds. It has not been definitively identified as the bromoperoxidase of higher eukaryotes, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haloperoxidase
Haloperoxidases are peroxidases that are able to mediate the oxidation of halides by hydrogen peroxide. Both halides and hydrogen peroxide are widely available in the environment. The Nernst equation shows that hydrogen peroxide can oxidize chloride (E°= 1.36 V), bromide (E°= 1.09 V) and iodide (E°= 0.536 V) from a thermodynamic perspective under natural conditions, i.e., a temperature range of about 0–30 °C and a pH ranging from about 3 (humic soil layer) to about 8 (sea water). Fluoride (E°= 2.87 V) cannot be oxidized by hydrogen peroxide. Classification The table shows the classification of haloperoxidases according to the halides whose oxidation they are able to catalyze. The classification of these enzymes by substrate-usability does not necessarily indicate enzyme substrate ''preference.'' For example, although eosinophil peroxidase is ''able'' to oxidize chloride, it preferentially oxidizes bromide. The mammalian haloperoxidases myeloperoxidase (MPO), lactopero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corallina Pilulifera
''Corallina'' is a genus of red seaweeds with hard, abrasive calcareous skeletons in the family Corallinaceae. They are stiff, branched plants with articulations. Species # '' Corallina aberrans'' (Yendo) K.R.Hind & G.W.Saunders # '' Corallina abundans'' Me.Lemoine # '' Corallina arbuscula'' Postels & Ruprecht # '' Corallina armata'' J.D.Hooker & Harvey # '' Corallina bathybentha'' E.Y.Dawson # '' Corallina berteroi'' Montagne ex Kützing # '' Corallina bifurca'' Kützing # '' Corallina binangonensis'' Ishijima # '' Corallina confusa'' Yendo # '' Corallina cossmannii'' Me.Lemoine # '' Corallina crassisima'' (Yendo) K.Hind & G.W.Saunders # ''Corallina declinata'' (Yendo) K.Hind & G.W.Saunders # ''Corallina ferreyrae'' E.Y.Dawson, Acleto & Foldvik # '' Corallina goughensis'' Y.M.Chamberlain # '' Corallina hombronii'' (Montagne) Montagne ex Kützing # '' Corallina maxima'' (Yendo) K.R.Hind & G.W.Saunders # '' Corallina melobesioides'' (Segawa) Martone, S.C.Lindstrom, K. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha/beta Hydrolase Superfamily
The alpha/beta hydrolase superfamily is a superfamily of hydrolytic enzymes of widely differing phylogenetic origin and catalytic function that share a common fold. The core of each enzyme is an alpha/beta-sheet (rather than a barrel), containing 8 beta strands connected by 6 alpha helices. The enzymes are believed to have diverged from a common ancestor, retaining little obvious sequence similarity, but preserving the arrangement of the catalytic residues. All have a catalytic triad, the elements of which are borne on loops, which are the best-conserved structural features of the fold. The alpha/beta hydrolase fold includes proteases, lipases, peroxidases, esterases, epoxide hydrolases and dehalogenases. Database The ESTHER database provides a large collection of information about this superfamily of proteins. Subfamilies * 3-oxoadipate enol-lactonase Human proteins containing this domain ABHD10; ABHD11; ABHD12; ABHD12B; ABHD13; ABHD2; ABHD3; ABHD4; ABHD5; ABHD6; A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus
''Bacillus'' (Latin "stick") is a genus of Gram-positive, rod-shaped bacteria, a member of the phylum ''Bacillota'', with 266 named species. The term is also used to describe the shape (rod) of other so-shaped bacteria; and the plural ''Bacilli'' is the name of the class of bacteria to which this genus belongs. ''Bacillus'' species can be either obligate aerobes which are dependent on oxygen, or facultative anaerobes which can survive in the absence of oxygen. Cultured ''Bacillus'' species test positive for the enzyme catalase if oxygen has been used or is present. ''Bacillus'' can reduce themselves to oval endospores and can remain in this dormant state for years. The endospore of one species from Morocco is reported to have survived being heated to 420 °C. Endospore formation is usually triggered by a lack of nutrients: the bacterium divides within its cell wall, and one side then engulfs the other. They are not true spores (i.e., not an offspring). Endospore formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrian Purple
Tyrian purple ( grc, πορφύρα ''porphúra''; la, purpura), also known as Phoenician red, Phoenician purple, royal purple, imperial purple, or imperial dye, is a reddish-purple natural dye. The name Tyrian refers to Tyre, Lebanon. It is secreted by several species of predatory sea snails in the family Muricidae, rock snails originally known by the name 'Murex'. In ancient times, extracting this dye involved tens of thousands of snails and substantial labor, and as a result, the dye was highly valued. The colored compound is 6,6′-dibromoindigo. History Biological pigments were often difficult to acquire, and the details of their production were kept secret by the manufacturers. Tyrian purple is a pigment made from the mucus of several species of Murex snail. Production of Tyrian purple for use as a fabric dye began as early as 1200 BCE by the Phoenicians, and was continued by the Greeks and Romans until 1453 CE, with the fall of Constantinople. The pigment was expensiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Murex
''Murex'' is a genus of medium to large sized predatory tropical sea snails. These are carnivorous marine gastropod molluscs in the family Muricidae, commonly called "murexes" or "rock snails".Houart, R.; Gofas, S. (2010). Murex Linnaeus, 1758. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138196 on 2011-04-09 The common name murex is still used for many species in the family Muricidae which were originally given the Latin generic name ''Murex'' in the past, but have more recently been regrouped into different newer genera. The word ''murex'' was used by Aristotle in reference to these kinds of snails, thus making it one of the oldest classical seashell names still in use by the scientific community. Fossil records This genus is known in the fossil records from the Cretaceous to the Quaternary (age range: from 125.45 to 0.0 million ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muricidae
Muricidae is a large and varied taxonomic family of small to large predatory sea snails, marine gastropod mollusks, commonly known as murex snails or rock snails. With about 1,600 living species, the Muricidae represent almost 10% of the Neogastropoda. Additionally, 1,200 fossil species have been recognized.Merle, D., Garrigues, B. & Pointier, J.-P. (2011). ''Fossil and Recent Muricidae of the World, Part Muricinae''. 648 pp., 182 colour plates, ConchBooks, Hackenheim. . Numerous subfamilies are recognized, although experts disagree about the subfamily divisions and the definitions of the genera. Many muricids have unusual shells which are considered attractive by shell collectors and by interior designers. Shell description Muricid shells are variably shaped, generally with a raised spire and strong sculpture with spiral ridges and often axial varices (typically three or more varices on each whorl), also frequently bearing spines, tubercles, or blade-like processes. Periostrac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroperoxidase
Chloride peroxidase () is a family of enzymes that catalyzes the chlorination of organic compounds. This enzyme combines the inorganic substrates chloride and hydrogen peroxide to produce the equivalent of Cl+, which replaces a proton in hydrocarbon substrate: :R-H + Cl− + H2O2 + H+ → R-Cl + 2 H2O In fact the source of "Cl+" is hypochlorous acid (HOCl). Many organochlorine compounds are biosynthesized in this way. This enzyme belongs to the family of oxidoreductases, specifically those acting on a peroxide as acceptors (peroxidases). The systematic name of this enzyme class is chloride:hydrogen-peroxide oxidoreductase. This enzyme is also called chloroperoxidase. It employs one cofactor which may be either heme or vanadium. (this paper also discussed chloroperoxidases. The heme-containing chloroperoxidase (CPO) exhibits peroxidase, catalase and cytochrome P450-like activities in addition to catalyzing halogenation reactions. Despite functional similarities with o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadate
In chemistry, a vanadate is an anionic coordination complex of vanadium. Often vanadate refers to oxoanions of vanadium, most of which exist in its highest oxidation state of +5. The complexes and are referred to as hexacyanovanadate(III) and nonachlorodivanadate(III), respectively. A simple vanadate ion is the tetrahedral orthovanadate anion, (which is also called vanadate(V)), which is present in e.g. sodium orthovanadate and in solutions of in strong base ( pH > 13). Conventionally this ion is represented with a single double bond, however this is a resonance form as the ion is a regular tetrahedron with four equivalent oxygen atoms. Additionally a range of polyoxovanadate ions exist which include discrete ions and "infinite" polymeric ions. There are also vanadates, such as rhodium vanadate, , which has a statistical rutile structure where the and ions randomly occupy the positions in the rutile lattice, that do not contain a lattice of cations and balancing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phaeophyta
Brown algae (singular: alga), comprising the class Phaeophyceae, are a large group of multicellular algae, including many seaweeds located in colder waters within the Northern Hemisphere. Brown algae are the major seaweeds of the temperate and polar regions. They are dominant on rocky shores throughout cooler areas of the world. Most brown algae live in marine environments, where they play an important role both as food and as a potential habitat. For instance, ''Macrocystis'', a kelp of the order Laminariales, may reach in length and forms prominent underwater kelp forests. Kelp forests like these contain a high level of biodiversity. Another example is ''Sargassum'', which creates unique floating mats of seaweed in the tropical waters of the Sargasso Sea that serve as the habitats for many species. Many brown algae, such as members of the order Fucales, commonly grow along rocky seashores. Some members of the class, such as kelps, are used by humans as food. Between 1,500 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodophyta
Red algae, or Rhodophyta (, ; ), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The majority of species (6,793) are found in the Florideophyceae (class), and mostly consist of multicellular, marine algae, including many notable seaweeds. Red algae are abundant in marine habitats but relatively rare in freshwaters. Approximately 5% of red algae species occur in freshwater environments, with greater concentrations found in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, there are no terrestrial species, which may be due to an evolutionary bottleneck in which the last common ancestor lost about 25% of its core genes and much of its evolutionary plasticity. The red algae form a distinct group characterized by having eukaryotic cells without flagella and centrioles, chloroplasts tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
