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Diacetyl Reductase ((S)-acetoin Forming)
Diacetyl reductase ((S)-acetoin forming) (, ''(S)-acetoin dehydrogenase'') is an enzyme with systematic name ''(S)-acetoin:NAD+ oxidoreductase''. This enzyme catalyses the following chemical reaction : (S)-acetoin + NAD+ \rightleftharpoons diacetyl + NADH + H+ The reaction is catalysed in the reverse direction. This activity is usually associated with butanediol dehydrogenase activity ( EC 1.1.1.4 or EC 1.1.1.76). While the butanediol dehydrogenase activity is reversible, diacetyl reductase activity is irreversible. This enzyme has been reported in the bacteria '' Geobacillus stearothermophilus'', '' Enterobacter aerogenes'' and '' Klebsiella pneumoniae''. Different from EC 1.1.1.303, diacetyl reductase ((R)-acetoin forming) Diacetyl reductase ((R)-acetoin forming) (, ''(R)-acetoin dehydrogenase'') is an enzyme with systematic name ''(R)-acetoin:NAD+ oxidoreductase''. This enzyme catalyses the following chemical reaction : (R)-acetoin + NAD+ \rightleftharpoons dia .... ... [...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] |
List Of Enzymes
This article lists enzymes by their classification in the International Union of Biochemistry and Molecular Biology's Enzyme Commission (EC) numbering system. * List of EC numbers (EC 5) * List of EC numbers (EC 6) :Oxidoreductases (EC 1) (Oxidoreductase) *Dehydrogenase * Luciferase *DMSO reductase :EC 1.1 (act on the CH-OH group of donors) * :EC 1.1.1 (with NAD+ or NADP+ as acceptor) ** Alcohol dehydrogenase (NAD) ** Alcohol dehydrogenase (NADP) **Homoserine dehydrogenase ** Aminopropanol oxidoreductase **Diacetyl reductase **Glycerol dehydrogenase **Propanediol-phosphate dehydrogenase ** glycerol-3-phosphate dehydrogenase (NAD+) ** D-xylulose reductase **L-xylulose reductase **Lactate dehydrogenase **Malate dehydrogenase **Isocitrate dehydrogenase ** HMG-CoA reductase * :EC 1.1.2 (with a cytochrome as acceptor) * :EC 1.1.3 (with oxygen as acceptor) **Glucose oxidase **L-gulonolactone oxidase **Thiamine oxidase **Xanthine oxidase * :EC 1.1.4 (with a disul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Chemical Reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (chemistry), products, which usually have properties different from the reactants. Reactions often consist of a sequence o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diacetyl Reductase
Diacetyl reductase is the name of two acetoin forming enzymes: * Diacetyl reductase ((R)-acetoin forming) * Diacetyl reductase ((S)-acetoin forming) Diacetyl reductase ((S)-acetoin forming) (, ''(S)-acetoin dehydrogenase'') is an enzyme with systematic name ''(S)-acetoin:NAD+ oxidoreductase''. This enzyme catalyses the following chemical reaction : (S)-acetoin + NAD+ \rightleftharpoons dia ... {{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geobacillus Stearothermophilus
''Geobacillus stearothermophilus'' (previously ''Bacillus stearothermophilus'') is a rod-shaped, Gram-positive bacterium and a member of the phylum Bacillota. The bacterium is a thermophile and is widely distributed in soil, hot springs, ocean sediment, and is a cause of spoilage in food products. It will grow within a temperature range of 30 to 75 °C. Some strains are capable of oxidizing carbon monoxide aerobically. It is commonly used as a challenge organism for sterilization validation studies and periodic check of sterilization cycles. The biological indicator contains spores of the organism on filter paper inside a vial. After sterilizing, the cap is closed, an ampule of growth medium inside of the vial is crushed and the whole vial is incubated. A color and/or turbidity change indicates the results of the sterilization process; no change indicates that the sterilization conditions were achieved, otherwise the growth of the spores indicates that the sterilization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterobacter Aerogenes
''Klebsiella aerogenes'', previously known as ''Enterobacter aerogenes,'' is a Gram-negative, oxidase negative, catalase positive, citrate positive, indole negative, rod-shaped bacterium. The bacterium is approximately 1-3 microns in length, and is capable of motility via peritrichous flagella. ''Klebsiella aerogenes'' is a nosocomial and pathogenic bacterium that causes opportunistic infections including most types of infections. The majority are sensitive to most antibiotics designed for this bacteria class, but this is complicated by their inducible resistance mechanisms, particularly lactamase, which means that they quickly become resistant to standard antibiotics during treatment, requiring a change in antibiotic to avoid worsening of the sepsis. Some of the infections caused by ''K. aerogenes'' result from specific antibiotic treatments, venous catheter insertions, and/or surgical procedures. ''K. aerogenes'' is generally found in the human gastrointestinal tract and does ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klebsiella Pneumoniae
''Klebsiella pneumoniae'' is a Gram-negative, non-motile, encapsulated, lactose-fermenting, facultative anaerobic, rod-shaped bacterium. It appears as a mucoid lactose fermenter on MacConkey agar. Although found in the normal flora of the mouth, skin, and intestines, it can cause destructive changes to human and animal lungs if aspirated, specifically to the alveoli resulting in bloody, brownish or yellow colored jelly like sputum. In the clinical setting, it is the most significant member of the genus ''Klebsiella'' of the Enterobacteriaceae. ''K. oxytoca'' and ''K. rhinoscleromatis'' have also been demonstrated in human clinical specimens. In recent years, ''Klebsiella'' species have become important pathogens in nosocomial infections. It naturally occurs in the soil, and about 30% of strains can fix nitrogen in anaerobic conditions. As a free-living diazotroph, its nitrogen-fixation system has been much-studied, and is of agricultural interest, as ''K. pneumoniae'' has been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diacetyl Reductase ((R)-acetoin Forming)
Diacetyl reductase ((R)-acetoin forming) (, ''(R)-acetoin dehydrogenase'') is an enzyme with systematic name ''(R)-acetoin:NAD+ oxidoreductase''. This enzyme catalyses the following chemical reaction : (R)-acetoin + NAD+ \rightleftharpoons diacetyl + NADH + H+ The reaction is catalysed in the reverse direction. This activity is usually associated with butanediol dehydrogenase activity (EC 1.1.1.4 or EC 1.1.1.76). While the butanediol dehydrogenase activity is reversible, diacetyl reductase activity is irreversible. This enzyme has been reported in the yeast Saccharomyces cerevisiae ''Saccharomyces cerevisiae'' () (brewer's yeast or baker's yeast) is a species of yeast (single-celled fungus microorganisms). The species has been instrumental in winemaking, baking, and brewing since ancient times. It is believed to have been o .... This enzyme is different from EC 1.1.1.304, diacetyl reductase ((S)-acetoin forming). References EC 1.1.1 {{Enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
