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Perchlorate Reductase
Perchlorate reductase is an enzyme that catalyzes the chemical reactions: :ClO4− + 2 AH2 \rightleftharpoons ClO2− + 2 A + 2 H2O and :ClO3− + AH2 \rightleftharpoons ClO2− + A + H2O Thus, the substrates of this enzyme are a reduced electron acceptor (denoted AH2) and either chlorate or perchlorate, sometimes collectively denoted as (per)chlorate. The products are chlorite, an oxidized electron acceptor (denoted A), and water. It is closely related to the enzyme chlorate reductase, but is distinguished by its ability to reduce both perchlorate and chlorate, whereas chlorate reductase only acts on chlorate. Perchlorate reductase and chlorate reductase are closely related but form genetically distinct clades. As of February 2023, perchlorate reductase has not been assigned a specific Enzyme Commission number, but along with chlorate reductase (), it would presumably be a member of the EC 1.97.1.- oxidoreductase subclass. Some databases, including BRENDA, currently com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BRENDA
Brenda is a feminine given name in the English language. Origin The overall accepted origin for the female name Brenda is the Old Nordic male name ''Brandr'' meaning both ''torch'' and ''sword'': evidently the male name Brandr took root in areas of the British Isles under Nordic dominance and through being heard as '"Brenda" was eventually adopted as a female name. The name Brenda was probably influenced by the iconic Gaelic male name Brendan: although linguistically it is unlikely that the name Brendan would yield the name Brenda as its feminine form, the name Brenda is widely considered a feminine form of the name Brendan in Ireland, Scotland, and Wales. History The British Isles Occurring in the medieval legend of Madoc - the purported son of the 12th century historical Welsh ruler Owain Gwynedd by Brenda the daughter of a Viking overlord in Ireland - the name Brenda was apparently until the 19th century confined to the Northern Isles being an evident remnant of the Northern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorite Dismutase
Chlorite dismutase, also known as Chlorite O2-lyase (), is an enzyme that catalyzes the chemical reaction : ClO → Cl− + O2 Reactions that generate oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ... molecules are exceedingly rare in biology and difficult to mimic synthetically. Perchlorate - respiring bacteria enzymatically detoxify chlorite, ClO, the end product of the perchlorate, ClO, respiratory pathway, by converting it to dioxygen, O2, and chloride, Cl−. Chlorite dismutase is a heme-containing protein, but it bears no structural or sequence relationships with known peroxidases or other heme proteins and is part of a large family of proteins with more than one biochemical function. References {{Portal bar, Biology, border=no EC 1.13.11 Enzymes of unknown s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcobacter
''Arcobacter'' is a genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ... of Gram-negative, spiral-shaped bacteria in the phylum Campylobacterota.Madigan T, ''et al'' (2009) ''Brock Biology of Microorganisms'', 12th edition. San Francisco: Pearson Education It shows an unusually wide range of habitats, and some species can be human and animal pathogens. Species of the genus ''Arcobacter'' are found in both animal and environmental sources, making it unique among the Campylobacterota. This genus currently consists of five species: ''A. butzleri'', ''A. cryaerophilus'', ''A. skirrowii'', ''A. nitrofigilis'', and ''A. sulfidicus'', although several other potential novel species have recently been described from varying environments. Three of these five known species are pathogeni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campylobacterota
Campylobacterota are a phylum of bacteria. All species of this phylum are Gram-negative. The Campylobacterota consist of few known genera, mainly the curved to spirilloid ''Wolinella'' spp., ''Helicobacter'' spp., and '' Campylobacter'' spp. Most of the known species inhabit the digestive tracts of animals and serve as symbionts (''Wolinella'' spp. in cattle) or pathogens (''Helicobacter'' spp. in the stomach, ''Campylobacter'' spp. in the duodenum). Many Campylobacterota are motile with flagella. Numerous environmental sequences and isolates of Campylobacterota have also been recovered from hydrothermal vents and cold seep habitats. Examples of isolates include ''Sulfurimonas autotrophica'', ''Sulfurimonas paralvinellae'', ''Sulfurovum lithotrophicum'' and ''Nautilia profundicola''. A member of the phylum Campylobacterota occurs as an endosymbiont in the large gills of the deepwater sea snail ''Alviniconcha hessleri''. The Campylobacterota found at deep-sea hydrothermal vents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molybdenum
Molybdenum is a chemical element with the symbol Mo and atomic number 42 which is located in period 5 and group 6. The name is from Neo-Latin ''molybdaenum'', which is based on Ancient Greek ', meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele. The metal was first isolated in 1781 by Peter Jacob Hjelm. Molybdenum does not occur naturally as a free metal on Earth; it is found only in various oxidation states in minerals. The free element, a silvery metal with a grey cast, has the sixth-highest melting point of any element. It readily forms hard, stable carbides in alloys, and for this reason most of the world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. Most molybdenum compounds have low solubili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytochrome
Cytochromes are redox-active proteins containing a heme, with a central Fe atom at its core, as a cofactor. They are involved in electron transport chain and redox catalysis. They are classified according to the type of heme and its mode of binding. Four varieties are recognized by the International Union of Biochemistry and Molecular Biology (IUBMB), cytochromes a, cytochromes b, cytochromes c and cytochrome d. Cytochrome function is linked to the reversible redox change from ferrous (Fe(II)) to the ferric (Fe(III)) oxidation state of the iron found in the heme core. In addition to the classification by the IUBMB into four cytochrome classes, several additional classifications such as cytochrome o and cytochrome P450 can be found in biochemical literature. History Cytochromes were initially described in 1884 by Charles Alexander MacMunn as respiratory pigments (myohematin or histohematin). In the 1920s, Keilin rediscovered these respiratory pigments and named them the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrate Reductase
Nitrate reductases are molybdoenzymes that reduce nitrate (NO) to nitrite (NO). This reaction is critical for the production of protein in most crop plants, as nitrate is the predominant source of nitrogen in fertilized soils. Types Eukaryotic Eukaryotic nitrate reductases are part of the sulfite oxidase family of molybdoenzymes. They transfer electrons from NADH or NADPH to nitrate. Prokaryotic Prokaryotic nitrate reductases belong to the DMSO reductase family of molybdoenzymes and have been classified into three groups, assimilatory nitrate reductases (Nas), respiratory nitrate reductase (Nar), and periplasmic nitrate reductases (Nap). The active site of these enzymes is a Mo ion that is bound to the four thiolate functions of two pterin molecules. The coordination sphere of the Mo is completed by one amino-acid side chain and oxygen and/or sulfur ligands. The exact environment of the Mo ion in certain of these enzymes (oxygen versus sulfur as a sixth molybdenum lig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periplasm
The periplasm is a concentrated gel-like matrix in the space between the inner cytoplasmic membrane and the bacterial outer membrane called the ''periplasmic space'' in gram-negative bacteria. Using cryo-electron microscopy it has been found that a much smaller periplasmic space is also present in gram-positive bacteria., Matias, V. R., and T. J. Beveridge. 2005. Cryo-electron microscopy reveals native polymeric cell wall structure in Bacillus subtilis 168 and the existence of a periplasmic space. Mol. Microbiol. 56:240-251. ., Zuber B, Haenni M, Ribeiro T, Minnig K, Lopes F, Moreillon P, Dubochet J. 2006. Granular layer in the periplasmic space of Gram-positive bacteria and fine structures of Enterococcus gallinarum and Streptococcus gordonii septa revealed by cryo-electron microscopy of vitreous sections. J Bacteriol. 188:6652-6660. The periplasm may constitute up to 40% of the total cell volume of gram-negative bacteria, but is a much smaller percentage in gram-positive bacteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genes
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidoreductase
In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another, the oxidant, also called the electron acceptor. This group of enzymes usually utilizes NADP+ or NAD+ as cofactors. Transmembrane oxidoreductases create electron transport chains in bacteria, chloroplasts and mitochondria, including respiratory complexes I, II and III. Some others can associate with biological membranes as peripheral membrane proteins or be anchored to the membranes through a single transmembrane helix. in ...
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Catalysis
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
