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Formate Dehydrogenase
Formate dehydrogenases are a set of enzymes that catalyse the oxidation of formate to carbon dioxide, donating the electrons to a second substrate, such as NAD+ in formate:NAD+ oxidoreductase () or to a cytochrome in formate:ferricytochrome-b1 oxidoreductase (). This family of enzymes has attracted attention as inspiration or guidance on methods for the carbon dioxide fixation, relevant to global warming. Function NAD-dependent formate dehydrogenases are important in methylotrophic yeast and bacteria, being vital in the catabolism of C1 compounds such as methanol. The cytochrome-dependent enzymes are more important in anaerobic metabolism in prokaryotes. For example, in '' E. coli'', the formate:ferricytochrome-b1 oxidoreductase is an intrinsic membrane protein with two subunits and is involved in anaerobic nitrate respiration. NAD-dependent reaction Formate + NAD+ CO2 + NADH + H+ Cytochrome-dependent reaction Formate + 2 ferricytochrome b1 CO2 + 2 ferrocytochrome b1 + ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), 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, 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 include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formate Dehydrogenase H
Formate dehydrogenase (acceptor) (, ''FDHH'', ''FDH-H'', ''FDH-O'', ''formate dehydrogenase H'', ''formate dehydrogenase O'') is an enzyme with systematic name ''formate:acceptor oxidoreductase''. This enzyme catalyses the following chemical reaction : formate + acceptor \rightleftharpoons CO2 + reduced acceptor Formate dehydrogenase H is a cytoplasmic enzyme that oxidizes formate without oxygen transfer] transferring electrons to a hydrogenase A hydrogenase is an enzyme that Catalysis, catalyses the reversible Redox, oxidation of molecular hydrogen (H2), as shown below: Hydrogen oxidation () is coupled to the reduction of electron acceptors such as oxygen, nitrate, Ferric, ferric i .... References External links * {{Portal bar, Biology, border=no EC 1.1.99 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolism
Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks of proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their Structures#Biological, structures, and respond to their environments. The word ''metabolism'' can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary (or intermediate) metabolism. Metabolic reactions may be categorized as ''catabolic''—the ''breaking down'' of compounds (for example, of glucose to pyruvate by c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Respiration
Cellular respiration is the process of oxidizing biological fuels using an inorganic electron acceptor, such as oxygen, to drive production of adenosine triphosphate (ATP), which stores chemical energy in a biologically accessible form. Cellular respiration may be described as a set of metabolic reactions and processes that take place in the cells of organisms to transfer chemical energy from nutrients to ATP, with the flow of electrons to an electron acceptor, and then release waste products. If the electron acceptor is oxygen, the process is more specifically known as aerobic cellular respiration. If the electron acceptor is a molecule other than oxygen, this is anaerobic cellular respiration. Fermentation, which is also an anaerobic process, is not respiration, as no external electron acceptor is involved. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, producing large amounts of energy (ATP). Respiration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microbial Metabolism
Microbial metabolism is the means by which a microbe obtains the energy and nutrients (e.g. carbon) it needs to live and reproduce. Microbes use many different types of metabolic strategies and species can often be differentiated from each other based on metabolic characteristics. The specific metabolic properties of a microbe are the major factors in determining that microbe's ecological niche, and often allow for that microbe to be useful in industrial processes or responsible for biogeochemical cycles. Types All microbial metabolisms can be arranged according to three principles: 1. How the organism obtains carbon for synthesizing cell mass:Morris, J. et al. (2019). "Biology: How Life Works", 3rd edition, W. H. Freeman. * autotrophic – carbon is obtained from carbon dioxide () * heterotrophic – carbon is obtained from organic compounds * mixotrophic – carbon is obtained from both organic compounds and by fixing carbon dioxide 2. How the organism obtains reducing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formate Dehydrogenase (NADP+)
Formate dehydrogenases are a set of enzymes that catalyse the oxidation of formate to carbon dioxide, donating the electrons to a second substrate, such as Nicotinamide adenine dinucleotide, NAD+ in formate:NAD+ oxidoreductase () or to a cytochrome in formate:ferricytochrome-b1 oxidoreductase (). This family of enzymes has attracted attention as inspiration or guidance on methods for the carbon dioxide fixation, relevant to global warming. Function NAD-dependent formate dehydrogenases are important in methylotrophic yeast and bacteria, being vital in the catabolism of C1 compounds such as methanol. The cytochrome-dependent enzymes are more important in anaerobic metabolism in prokaryotes. For example, in ''E. coli'', the formate:ferricytochrome-b1 oxidoreductase is an intrinsic membrane protein with two subunits and is involved in anaerobic nitrate respiration. NAD-dependent reaction Formate + NAD+ CO2 + NADH + H+ Cytochrome-dependent reaction Formate + 2 ferricytochrome b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formate Dehydrogenase (cytochrome-c-553)
In enzymology, a formate dehydrogenase (cytochrome-c-553) () is an enzyme that catalyzes the chemical reaction :formate + ferricytochrome c-553 \rightleftharpoons CO2 + ferrocytochrome c-553 Thus, the two substrates of this enzyme are formate and ferricytochrome c-553, whereas its two products are CO2 and ferrocytochrome c-553. This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with a cytochrome as acceptor. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivi ... of this enzyme class is formate:ferricytochrome-c-553 oxidoreductase. References * * EC 1.2.2 Enzymes of unknown structure {{1.2-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formate Dehydrogenase (cytochrome)
In enzymology, a formate dehydrogenase (cytochrome) () is an enzyme that catalyzes the chemical reaction :formate + 2 ferricytochrome b1 \rightleftharpoons CO2 + 2 ferrocytochrome b1 + 2 H+ Thus, the two substrates of this enzyme are formate and ferricytochrome b1, whereas its 3 products are CO2, ferrocytochrome b1, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with a cytochrome as acceptor. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivi ... of this enzyme class is formate:ferricytochrome-b1 oxidoreductase. Other names in common use include formate dehydrogenase, and formate:cytochrome b1 oxidoreductase. This enzyme participates in glyoxylate and dicarboxylate metabolism. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colored Electron Tunneling F-DHN
''Colored'' (or ''coloured'') is a racial descriptor historically used in the United States during the Jim Crow era to refer to an African American. In many places, it may be considered a slur. Dictionary definitions The word ''colored'' was first used in the 14th century but with a meaning other than race or ethnicity. The earliest uses of the term to denote a member of dark-skinned groups of peoples occurred in the second part of the 18th century in reference to South America. According to the ''Oxford English Dictionary'', "colored" was first used in this context in 1758 to translate the Spanish term () in Antonio de Ulloa's ''A voyage to South America''. The term came in use in the United States during the early 19th century, and it then was adopted by emancipated slaves as a term of racial pride after the end of the American Civil War until it was replaced as a self-designation by ''Black'' or ''African-American'' during the second part of the 20th century. Due to its u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin K2
Vitamin K2 or menaquinone (MK) () is one of three types of vitamin K, the other two being vitamin K1 ( phylloquinone) and K3 (menadione). K2 is both a tissue and bacterial product (derived from vitamin K1 in both cases) and is usually found in animal products or fermented foods. The number ''n'' of isoprenyl units in their side chain differs and ranges from 4 to 13, hence vitamin K2 consists of various forms. It is indicated as a suffix (-n), e. g. MK-7 or MK-9. * The most common in the human diet is the short-chain, water-soluble menatetrenone (MK-4), which is commonly found in animal products. However, at least one published study concluded that "MK-4 present in food does not contribute to the vitamin K status as measured by serum vitamin K levels." The MK-4 in animal (including human) tissue is made from dietary plant vitamin K1. This process can be accomplished by animal tissues alone, as it proceeds in germ-free rodents. * Long-chain menaquinones (longer than MK-4) include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytochrome B
Cytochrome b is a protein found in the membranes of aerobic cells. In eukaryotic mitochondria (inner membrane) and in aerobic prokaryotes, cytochrome b is a component of respiratory chain complex III () — also known as the bc1 complex or ubiquinol-cytochrome c reductase. In plant chloroplasts and cyanobacteria, there is a homologous protein, cytochrome b6, a component of the plastoquinone-plastocyanin reductase (), also known as the b6f complex. These complexes are involved in electron transport, the pumping of protons to create a proton-motive force ( PMF). This proton gradient is used for the generation of ATP. These complexes play a vital role in cells. Structure and function Cytochrome b/b6 is an integral membrane protein of approximately 400 amino acid residues that probably has 8 transmembrane segments. In plants and cyanobacteria, cytochrome b6 consists of two protein subunits encoded by the petB and petD genes. Cytochrome b/b6 non-covalently binds two heme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferredoxin
Ferredoxins (from Latin ''ferrum'': iron + redox, often abbreviated "fd") are iron–sulfur proteins that mediate electron transfer in a range of metabolic reactions. The term "ferredoxin" was coined by D.C. Wharton of the DuPont Co. and applied to the "iron protein" first purified in 1962 by Mortenson, Valentine, and Carnahan from the anaerobic organism, anaerobic bacterium ''Clostridium pasteurianum''. Another redox protein, isolated from spinach chloroplasts, was termed "chloroplast ferredoxin". The chloroplast ferredoxin is involved in both cyclic and non-cyclic photophosphorylation reactions of photosynthesis. In non-cyclic photophosphorylation, ferredoxin is the last electron acceptor thus reducing the enzyme NADP+ reductase. It accepts electrons produced from sunlight-Electron excitation, excited chlorophyll and transfers them to the enzyme ferredoxin: NADP+ oxidoreductase . Ferredoxins are small proteins containing iron and sulfur atoms organized as iron–sulfur clusters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
