Definitions containing nad nucleosidase

We've found 153 definitions:

NADH

NADH

nicotinamide adenine dinucleotide (NAD) carrying two electrons and bonded with a hydrogen (H) ion; the reduced form of NAD.

— Wiktionary

nadp

nicotinamide adenine dinucleotide phosphate, NADP

a coenzyme similar to NAD and present in most living cells but serves as a reductant in different metabolic processes

— Princeton's WordNet

nicotinamide adenine dinucleotide phosphate

nicotinamide adenine dinucleotide phosphate, NADP

a coenzyme similar to NAD and present in most living cells but serves as a reductant in different metabolic processes

— Princeton's WordNet

depth-first search

depth-first search

an algorithm for traversing a tree or graph where one starts at the root nad explores as far as possible along each branch before backtracking

— Wiktionary

Fructuronate reductase

Fructuronate reductase

In enzymology, a fructuronate reductase is an enzyme that catalyzes the chemical reaction++ Thus, the two substrates of this enzyme are D-mannonate and NAD+, whereas its 3 products are D-fructuronate, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is D-mannonate:NAD+ 5-oxidoreductase. Other names in common use include mannonate oxidoreductase, mannonic dehydrogenase, D-mannonate dehydrogenase, and D-mannonate:NAD+ oxidoreductase. This enzyme participates in pentose and glucuronate interconversions.

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Dihydrodipicolinate reductase

Dihydrodipicolinate reductase

In enzymology, a dihydrodipicolinate reductase is an enzyme that catalyzes the chemical reaction+ The 3 substrates of this enzyme are-2,3,4,5-tetrahydropyridine-2,6-dicarboxylate, NAD+, and NADP+, whereas its 4 products are 2,3-dihydrodipicolinate, NADH, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is-2,3,4,5-tetrahydropyridine-2,6-dicarboxylate:NAD+ oxidoreductase. Other names in common use include dihydrodipicolinic acid reductase, and 2,3,4,5-tetrahydrodipicolinate:NAD+ oxidoreductase. This enzyme participates in lysine biosynthesis.

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Leucine dehydrogenase

Leucine dehydrogenase

In enzymology, a leucine dehydrogenase is an enzyme that catalyzes the chemical reaction++ The 3 substrates of this enzyme are L-leucine, H2O, and NAD+, whereas its 4 products are 4-methyl-2-oxopentanoate, NH3, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH2 group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is L-leucine:NAD+ oxidoreductase. Other names in common use include L-leucine dehydrogenase, L-leucine:NAD+ oxidoreductase, deaminating, and LeuDH. This enzyme participates in valine, leucine and isoleucine degradation and valine, leucine and isoleucine biosynthesis.

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homolactic fermentation

homolactic fermentation

Any form of fermentation that produces a single acid, but especially the anaerobic conversion of pyruvic acid into lactic acid with concomitant oxidation of NADH to NAD

— Wiktionary

Homoserine dehydrogenase

Homoserine dehydrogenase

In enzymology, a homoserine dehydrogenase is an enzyme that catalyzes the chemical reaction++ The 2 substrates of this enzyme are L-homoserine and NAD+, whereas its 3 products are L-aspartate 4-semialdehyde, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is L-homoserine:NAD+ oxidoreductase. Other names in common use include HSDH, and HSD. Homoserine dehydrogenase catalyses the third step in the aspartate pathway; the NAD-dependent reduction of aspartate beta-semialdehyde into homoserine. Homoserine is an intermediate in the biosynthesis of threonine, isoleucine, and methionine.

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Alanine dehydrogenase

Alanine dehydrogenase

Alanine dehydrogenase is an enzyme that catalyzes the chemical reaction++ The 3 substrates of this enzyme are L-alanine, water, and nicotinamide adenine dinucleotide+, whereas its 4 products are pyruvate, ammonia, NADH, and hydrogen ion. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH2 group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is L-alanine:NAD+ oxidoreductase. Other names in common use include AlaDH, L-alanine dehydrogenase, NAD+-linked alanine dehydrogenase, alpha-alanine dehydrogenase, NAD+-dependent alanine dehydrogenase, alanine oxidoreductase, and NADH-dependent alanine dehydrogenase. This enzyme participates in taurine and hypotaurine metabolism and reductive carboxylate cycle.

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Glycolaldehyde dehydrogenase

Glycolaldehyde dehydrogenase

In enzymology, a glycolaldehyde dehydrogenase is an enzyme that catalyzes the chemical reaction++ The 3 substrates of this enzyme are glycolaldehyde, NAD+, and H2O, whereas its 3 products are glycolate, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is glycolaldehyde:NAD+ oxidoreductase. This enzyme is also called glycol aldehyde dehydrogenase. This enzyme participates in glyoxylate and dicarboxylate metabolism.

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Retinal dehydrogenase

Retinal dehydrogenase

In enzymology, a retinal dehydrogenase is an enzyme that catalyzes the chemical reaction++ The 3 substrates of this enzyme are retinal, NAD+, and H2O, whereas its 3 products are retinoic acid, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is retinal:NAD+ oxidoreductase. This enzyme is also called cytosolic retinal dehydrogenase. This enzyme participates in retinol metabolism. It has 2 cofactors: FAD, and Metal.

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Kazin

Kazin

Kazin is a village in the administrative district of Gmina Nakło nad Notecią, within Nakło County, Kuyavian-Pomeranian Voivodeship, in north-central Poland. It lies approximately 10 kilometres north-east of Nakło nad Notecią and 20 km west of Bydgoszcz. The village has a population of 230.

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Lísek

Lísek

Lísek is a village and municipality in Žďár nad Sázavou District in the Vysočina Region of the Czech Republic. The municipality covers an area of 16.71 square kilometres, and has a population of 381. Lísek lies approximately 19 kilometres east of Žďár nad Sázavou, 49 km north-east of Jihlava, and 139 km south-east of Prague.

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na

na

.na is the Internet country code top-level domain for Namibia. Registry/Registrar Separation has been implemented, with Namibian and Foreign Registrars being accredited. The Registry supports a Web/GUI interface and EPP. Registrations are available at the second level or at the third level beneath various names that include some redundant choices. Prices vary depending on the level at which a registration is made, the second-level name a third-level registration is beneath, and whether the registrant is domestic or foreign. .na domains cost approximately 4000 NAD a year for domestic and 40000 NAD for foreign registrants, .com.na 400 and 4000 NAD respectively, and .co.na 500 NAD for both. NA-NiC is a member of CoCCA and uses their Dispute Resolution.

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Prephenate dehydrogenase

Prephenate dehydrogenase

In enzymology, a prephenate dehydrogenase is an enzyme that catalyzes the chemical reaction+ Thus, the two substrates of this enzyme are prephenate and NAD+, whereas its 3 products are 4-hydroxyphenylpyruvate, CO2, and NADH. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is prephenate:NAD+ oxidoreductase. Other names in common use include hydroxyphenylpyruvate synthase, and chorismate mutase---prephenate dehydrogenase. This enzyme participates in phenylalanine, tyrosine and tryptophan biosynthesis and novobiocin biosynthesis.

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Rokle

Rokle

Rokle is a village and municipality in Chomutov District in the Ústí nad Labem Region of the Czech Republic. The municipality covers an area of 13.56 square kilometres, and has a population of 242. Rokle lies approximately 15 kilometres south-west of Chomutov, 63 km south-west of Ústí nad Labem, and 85 km west of Prague.

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Nicotinamide adenine dinucleotide

Nicotinamide adenine dinucleotide

Nicotinamide adenine dinucleotide, abbreviated NAD+, is a coenzyme found in all living cells. The compound is a dinucleotide, since it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine base and the other nicotinamide. In metabolism, NAD+ is involved in redox reactions, carrying electrons from one reaction to another. The coenzyme is, therefore, found in two forms in cells: NAD+ is an oxidizing agent – it accepts electrons from other molecules and becomes reduced. This reaction forms NADH, which can then be used as a reducing agent to donate electrons. These electron transfer reactions are the main function of NAD+. However, it is also used in other cellular processes, the most notable one being a substrate of enzymes that add or remove chemical groups from proteins, in posttranslational modifications. Because of the importance of these functions, the enzymes involved in NAD+ metabolism are targets for drug discovery. In organisms, NAD+ can be synthesized from simple building-blocks from the amino acids tryptophan or aspartic acid. In an alternative fashion, more complex components of the coenzymes are taken up from food as the vitamin called niacin. Similar compounds are released by reactions that break down the structure of NAD+. These preformed components then pass through a salvage pathway that recycles them back into the active form. Some NAD+ is also converted into nicotinamide adenine dinucleotide phosphate; the chemistry of this related coenzyme is similar to that of NAD+, but it has different roles in metabolism.

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Pustina

Pustina

Pustina is a village and municipality in Ústí nad Orlicí District in the Pardubice Region of the Czech Republic. The municipality covers an area of 2.83 square kilometres, and has a population of 66. Pustina lies approximately 23 kilometres west of Ústí nad Orlicí, 29 km south-east of Pardubice, and 123 km east of Prague.

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Malíč

Malíč

Malíč is a village and municipality in Litoměřice District in the Ústí nad Labem Region of the Czech Republic. The municipality covers an area of 1.41 square kilometres, and has a population of 151. Malíč lies approximately 3 kilometres north-west of Litoměřice, 14 km south of Ústí nad Labem, and 56 km north-west of Prague.

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Kamýk

Kamýk

Kamýk is a village and municipality in Litoměřice District in the Ústí nad Labem Region of the Czech Republic. The municipality covers an area of 5.77 square kilometres, and has a population of 139. Kamýk lies approximately 5 kilometres north-west of Litoměřice, 11 km south of Ústí nad Labem, and 59 km north-west of Prague.

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FMN reductase

FMN reductase

In enzymology, an FMN reductase is an enzyme that catalyzes the chemical reaction+ The 3 substrates of this enzyme are FMNH2, NAD+, and NADP+, whereas its 4 products are FMN, NADH, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is FMNH2:NAD+ oxidoreductase. Other names in common use include NADH-FMN reductase, NADH-dependent FMN reductase, NADH:FMN oxidoreductase, NADH:flavin oxidoreductase, NADH2 dehydrogenase, NADH2:FMN oxidoreductase, SsuE, riboflavin mononucleotide reductase, flavine mononucleotide reductase, riboflavin mononucleotide reductase, flavin mononucleotide reductase, and riboflavine mononucleotide reductase.

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Lactate dehydrogenase

Lactate dehydrogenase

A lactate dehydrogenase is an enzyme present in a wide variety of organisms, including plants and animals. Lactate dehydrogenases exist in four distinct enzyme classes. Two of them are cytochrome c-dependent enzymes, each acting on either D-lactate or L-lactate. The other two are NAD-dependent enzymes, each acting on either D-lactate or L-lactate. This article is about the NAD-dependent L-lactate dehydrogenase.

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Galactose Dehydrogenases

Galactose Dehydrogenases

D-Galactose:NAD(P)+ 1-oxidoreductases. Catalyzes the oxidation of D-galactose in the presence of NAD+ or NADP+ to D-galactono-gamma-lactone and NADH or NADPH. Includes EC 1.1.1.48 and EC 1.1.1.120.

— U.S. National Library of Medicine

Terezín

Terezín

Terezín is a former military fortress and adjacent walled garrison town in the Ústí nad Labem Region of the Czech Republic.

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Sirtuin

Sirtuin

Sirtuin or Sir2 proteins are a class of proteins that possess either mono-ribosyltransferase, or deacylase activity, including deacetylase, desuccinylase, demalonylase, demyristoylase and depalmitoylase activity. Sirtuins regulate important biological pathways in bacteria, archaea and eukaryotes. The name Sir2 comes from the yeast gene 'silent mating-type information regulation 2', the gene responsible for cellular regulation in yeast. Sirtuins have been implicated in influencing a wide range of cellular processes like aging, transcription, apoptosis, inflammation and stress resistance, as well as energy efficiency and alertness during low-calorie situations. Sirtuins can also control circadian clocks and mitochondrial biogenesis. Yeast Sir2 and some, but not all, sirtuins are protein deacetylases. Unlike other known protein deacetylases, which simply hydrolyze acetyl-lysine residues, the sirtuin-mediated deacetylation reaction couples lysine deacetylation to NAD hydrolysis. This hydrolysis yields O-acetyl-ADP-ribose, the deacetylated substrate and nicotinamide, itself an inhibitor of sirtuin activity. The dependence of sirtuins on NAD links their enzymatic activity directly to the energy status of the cell via the cellular NAD:NADH ratio, the absolute levels of NAD, NADH or nicotinamide or a combination of these variables.

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Lubina

Lubina

Lubina is a village and municipality in Nové Mesto nad Váhom District in the Trenčín Region of western Slovakia.

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Hydroxypyruvate reductase

Hydroxypyruvate reductase

In enzymology, a hydroxypyruvate reductase is an enzyme that catalyzes the chemical reaction+ The 3 substrates of this enzyme are D-glycerate, NAD+, and NADP+, whereas its 4 products are hydroxypyruvate, NADH, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is D-glycerate:NADP+ 2-oxidoreductase. Other names in common use include beta-hydroxypyruvate reductase, NADH:hydroxypyruvate reductase, and D-glycerate dehydrogenase. This enzyme participates in glycine, serine and threonine metabolism and glyoxylate and dicarboxylate metabolism.

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Urocanase

Urocanase

Urocanase is the enzyme that catalyzes the second step in the degradation of histidine, the hydration of urocanate into imidazolonepropionate. Inherited deficiency of urocanase leads to elevated levels of urocanic acid in the urine, a condition known as urocanic aciduria. Urocanase is found in some bacteria, in the liver of many vertebrates and has also been found in the plant Trifolium repens. Urocanase is a protein of about 60 Kd, it binds tightly to NAD+ and uses it as an electrophil cofactor. A conserved cysteine has been found to be important for the catalytic mechanism and could be involved in the binding of the NAD+.

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Zásada

Zásada

Zásada is a market town and municipality in Jablonec nad Nisou District in the Liberec Region of the Czech Republic.

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Saccharopine Dehydrogenases

Saccharopine Dehydrogenases

Amine oxidoreductases that use either NAD+ (EC 1.5.1.7) or NADP+ (EC 1.5.1.8) as an acceptor to form L-LYSINE or NAD+ (EC 1.5.1.9) or NADP+ (EC 1.5.1.10) as an acceptor to form L-GLUTAMATE. Deficiency of this enzyme causes HYPERLYSINEMIAS.

— U.S. National Library of Medicine

Isocitrate dehydrogenase

Isocitrate dehydrogenase

Isocitrate dehydrogenase and is an enzyme that catalyzes the oxidative decarboxylation of isocitrate, producing alpha-ketoglutarate and CO2. This is a two-step process, which involves oxidation of isocitrate to oxalosuccinate, followed by the decarboxylation of the carboxyl group beta to the ketone, forming alpha-ketoglutarate. In humans, IDH exists in three isoforms: IDH3 catalyzes the third step of the citric acid cycle while converting NAD+ to NADH in the mitochondria. The isoforms IDH1 and IDH2 catalyze the same reaction outside the context of the citric acid cycle and use NADP+ as a cofactor instead of NAD+. They localize to the cytosol as well as the mitochondrion and peroxisome

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O-Acetyl-ADP-Ribose

O-Acetyl-ADP-Ribose

An acetyl ester of ADENOSINE DIPHOSPHATE RIBOSE formed during NAD-dependent deacetylation of proteins by SIRTUINS. The acetate group resides on the ribose ring where nicotinamide was cleaved from NAD during the reaction. Several isomers of O-acetyl-ADP-ribose have been isolated from the reaction.

— U.S. National Library of Medicine

Sirtuins

Sirtuins

A homologous family of regulatory enzymes that are structurally related to the protein silent mating type information regulator 2 (Sir2) found in Saccharomyces cerevisiae. Sirtuins contain a central catalytic core region which binds NAD. Several of the sirtuins utilize NAD to deacetylate proteins such as HISTONES and are categorized as GROUP III HISTONE DEACETYLASES. Several other sirtuin members utilize NAD to transfer ADP-RIBOSE to proteins and are categorized as MONO ADP-RIBOSE TRANSFERASES, while a third group of sirtuins appears to have both deacetylase and ADP ribose transferase activities.

— U.S. National Library of Medicine

Nicotinamide-Nucleotide Adenylyltransferase

Nicotinamide-Nucleotide Adenylyltransferase

An enzyme that catalyzes reversibly the transfer of the adenylyl moiety of ATP to the phosphoryl group of NMN to form NAD+ and pyrophosphate. The enzyme is found predominantly in the nuclei and catalyzes the final reaction in the major pathway for the biosynthesis of NAD in mammals. EC 2.7.7.1.

— U.S. National Library of Medicine

Adenosylhomocysteinase

Adenosylhomocysteinase

Adenosylhomocysteinase is an enzyme that converts S-adenosylhomocysteine to homocysteine and adenosine. This enzyme catalyses the following chemical reaction The enzyme contains one tightly bound NAD+ per subunit.

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Dehydrogenase

Dehydrogenase

A dehydrogenase is an enzyme that oxidizes a substrate by a reduction reaction that transfers one or more hydrides to an electron acceptor, usually NAD+/NADP+ or a flavin coenzyme such as FAD or FMN.

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Hartnup disease

Hartnup disease

Hartnup disease is an autosomal recessive metabolic disorder affecting the absorption of nonpolar amino acids. Niacin is a precursor to nicotinamide, a necessary component of NAD+. The causative gene, SLC6A19, is located on chromosome 5.

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Niacin

Niacin

Niacin is an organic compound with the formula C 6H 5NO 2 and, depending on the definition used, one of the 40 to 80 essential human nutrients. Niacin is one of five vitamins associated with a pandemic deficiency disease: niacin deficiency, vitamin C deficiency, thiamin deficiency, vitamin D deficiency, vitamin A deficiency. Niacin has been used for over 50 years to increase levels of HDL in the blood and has been found to modestly decrease the risk of cardiovascular events in a number of controlled human trials. This colorless, water-soluble solid is a derivative of pyridine, with a carboxyl group at the 3-position. Other forms of vitamin B3 include the corresponding amide, nicotinamide, where the carboxyl group has been replaced by a carboxamide group, as well as more complex amides and a variety of esters. Nicotinic acid and niacinamide are convertible to each other with steady world demand rising from 8500 tonnes per year in 1980s to 40,000 in recent years. Niacin cannot be directly converted to nicotinamide, but both compounds could be converted to NAD and NADP in vivo. Nicotinic acid, nicotinamid, and tryptophan are co-factors for nicotinamide adenine dinucleotide and nicotinamide adenine dinucleotide phosphate. NAD converts to NADP by phosphorylation in the presence of the enzyme NAD+ kinase. NADP and NAD are coenzyme for many dehydrogenases, participating in many hydrogen transfer processes. NAD is important in catabolism of fat, carbohydrate, protein and alcohol as well as cell signaling and DNA repair and NADP mostly in anabolism reaction such as fatty acid and cholesterol synthesis. High energy requirements or high turnover rate organs are usually the most susceptible to their deficiency. Although the two are identical in their vitamin activity, nicotinamide does not have the same pharmacological effects as niacin. Nicotinamide does not reduce cholesterol or cause flushing. Nicotinamide may be toxic to the liver at doses exceeding 3 g/day for adults. Niacin is a precursor to NAD+/NADH and NADP+/NADPH, which play essential metabolic roles in living cells. Niacin is involved in both DNA repair, and the production of steroid hormones in the adrenal gland.

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Hrob

Hrob

Hrob is a town in the Teplice District of the Ústí nad Labem Region in the Czech Republic. It has a population of 2,092 and an area of 11.09 km². The first record of this town's existence dates back to 1282.

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Betaine-Aldehyde Dehydrogenase

Betaine-Aldehyde Dehydrogenase

An NAD+ dependent enzyme that catalyzes the oxidation of betain aldehyde to BETAINE.

— U.S. National Library of Medicine

Slovanka

Slovanka

Slovanka is a hill situated 820 m above sea level in the central Jizera Mountains in the area of Lučany nad Nisou, between Královka and Bramberk. The view tower next to the hut, built in the year 1887 from iron, is 14 metres high, with 56 steps to the top. It was rebuilt for 550.000 Kč and reopened on 5 July 2000.

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Glycolaldehyde Dehydrogenase

Glycolaldehyde Dehydrogenase

An enzyme that catalyzes the oxidation of glycolaldehyde to glycolate, using NAD and NADP as COENZYMES.

— U.S. National Library of Medicine

Oxidoreductase

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.

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Cyclic ADP-Ribose

Cyclic ADP-Ribose

A pyridine nucleotide that mobilizes CALCIUM. It is synthesized from nicotinamide adenine dinucleotide (NAD) by ADP RIBOSE CYCLASE.

— U.S. National Library of Medicine

Anahata

Anahata

Anahata is the fourth primary chakra according to the Hindu Yogic, Shakta and Buddhist Tantric traditions. In Sanskrit the word anahata means unhurt, unstruck and unbeaten. Anahata Nad refers to the Vedic concept of unstruck sound, the sound of the celestial realm. Ananhata is usually associated with a calm serene sound void of violence.

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Aminomuconate-Semialdehyde Dehydrogenase

Aminomuconate-Semialdehyde Dehydrogenase

An NAD+ dependent enzyme that catalyzes the oxidation of 2-aminomuconate 6-semialdehyde to 2-aminomuconate.

— U.S. National Library of Medicine

Glycerol-3-Phosphate Dehydrogenase (NAD+)

Glycerol-3-Phosphate Dehydrogenase (NAD+)

An NAD-dependent enzyme that catalyzes the oxidation of sn-glycerol 3-phosphate to glycerone phosphate.

— U.S. National Library of Medicine

Malate Dehydrogenase

Malate Dehydrogenase

An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 1.1.1.37.

— U.S. National Library of Medicine

Sirtuin 1

Sirtuin 1

Sirtuin 1, also known as NAD-dependent deacetylase sirtuin-1, is a protein that in humans is encoded by the SIRT1 gene. SIRT1 stands for sirtuin 1, referring to the fact that its sirtuin homolog in yeast is Sir2. SIRT1 is an enzyme that deacetylates proteins that contribute to cellular regulation.

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Hydroxymethylglutaryl-CoA-Reductases, NADP-dependent

Hydroxymethylglutaryl-CoA-Reductases, NADP-dependent

Specific hydroxymethylglutaryl CoA reductases that utilize the cofactor NAD. In liver enzymes of this class are involved in cholesterol biosynthesis.

— U.S. National Library of Medicine

Acetoin Dehydrogenase

Acetoin Dehydrogenase

An enzyme that catalyzes the conversion of acetoin to diacetyl in the presence of NAD. EC 1.1.1.5.

— U.S. National Library of Medicine

Poly Adenosine Diphosphate Ribose

Poly Adenosine Diphosphate Ribose

A polynucleotide formed from the ADP-RIBOSE moiety of nicotinamide-adenine dinucleotide (NAD) by POLY(ADP-RIBOSE) POLYMERASES.

— U.S. National Library of Medicine

Uridine Diphosphate Glucose Dehydrogenase

Uridine Diphosphate Glucose Dehydrogenase

An enzyme that catalyzes the oxidation of UDPglucose to UDPglucuronate in the presence of NAD+. EC 1.1.1.22.

— U.S. National Library of Medicine

Apiose

Apiose

Apiose is a branched-chain sugar found as residues in galacturonans-type pectins; that occurs in parsley and many other plants. Apiose 1-reductase uses D-apiitol and NAD+ to produce D-apiose, NADH, and H+. Flavone apiosyltransferase uses UDP-apiose and 5,7,4'-trihydroxyflavone 7-O-beta-D-glucoside to produce UDP, 5,7,4'-trihydroxyflavone, and 7-O-[beta-D-apiosyl--beta-D-glucoside.

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2-Oxoisovalerate Dehydrogenase (Acylating)

2-Oxoisovalerate Dehydrogenase (Acylating)

An NAD+ dependent enzyme that catalyzes the oxidation 3-methyl-2-oxobutanoate to 2-methylpropanoyl-CoA. It plays a role in the degradation of VALINE; LEUCINE; and ISOLEUCINE.

— U.S. National Library of Medicine

Methylenetetrahydrofolate Dehydrogenase (NAD+)

Methylenetetrahydrofolate Dehydrogenase (NAD+)

A NAD-dependent oxidoreductase that catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5,10-methenyl-tetrahdyrofolate. It has been found in a variety of microorganisms.

— U.S. National Library of Medicine

Quinone Reductases

Quinone Reductases

NAD(P)H:(quinone acceptor) oxidoreductases. A family that includes three enzymes which are distinguished by their sensitivity to various inhibitors. EC 1.6.99.2 (NAD(P)H DEHYDROGENASE (QUINONE);) is a flavoprotein which reduces various quinones in the presence of NADH or NADPH and is inhibited by dicoumarol. EC 1.6.99.5 (NADH dehydrogenase (quinone)) requires NADH, is inhibited by AMP and 2,4-dinitrophenol but not by dicoumarol or folic acid derivatives. EC 1.6.99.6 (NADPH dehydrogenase (quinone)) requires NADPH and is inhibited by dicoumarol and folic acid derivatives but not by 2,4-dinitrophenol.

— U.S. National Library of Medicine

11-beta-Hydroxysteroid Dehydrogenases

11-beta-Hydroxysteroid Dehydrogenases

Hydroxysteroid dehydrogenases that catalyzes the reversible conversion of CORTISOL to the inactive metabolite CORTISONE. Enzymes in this class can utilize either NAD or NADP as cofactors.

— U.S. National Library of Medicine

Glucose 1-Dehydrogenase

Glucose 1-Dehydrogenase

A glucose dehydrogenase that catalyzes the oxidation of beta-D-glucose to form D-glucono-1,5-lactone, using NAD as well as NADP as a coenzyme.

— U.S. National Library of Medicine

Spree

Spree

The Spree is a river that flows through the Saxony, Brandenburg and Berlin states of Germany, and in the Ústí nad Labem region of the Czech Republic. It is a left bank tributary of the River Havel and is approximately 400 kilometres in length. The reach of the river between the Dämeritzsee and Müggelsee to the east of Berlin is known as the Müggelspree.

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Dihydrolipoamide Dehydrogenase

Dihydrolipoamide Dehydrogenase

A flavoprotein containing oxidoreductase that catalyzes the reduction of lipoamide by NADH to yield dihydrolipoamide and NAD+. The enzyme is a component of several MULTIENZYME COMPLEXES.

— U.S. National Library of Medicine

Sirtuin 1

Sirtuin 1

A sirtuin family member found primarily in the CELL NUCLEUS. It is an NAD-dependent deacetylase with specificity towards HISTONES and a variety of proteins involved in gene regulation.

— U.S. National Library of Medicine

Myo-Inositol-1-Phosphate Synthase

Myo-Inositol-1-Phosphate Synthase

An enzyme that catalyzes the formation of myo-inositol-1-phosphate from glucose-6-phosphate in the presence of NAD. EC 5.5.1.4.

— U.S. National Library of Medicine

IMP Dehydrogenase

IMP Dehydrogenase

An enzyme that catalyzes the dehydrogenation of inosine 5'-phosphate to xanthosine 5'-phosphate in the presence of NAD. EC 1.1.1.205.

— U.S. National Library of Medicine

Group III Histone Deacetylases

Group III Histone Deacetylases

A subclass of histone deacetylases that are NAD-dependent. Several members of the SIRTUINS family are included in this subclass.

— U.S. National Library of Medicine

UDPglucose 4-Epimerase

UDPglucose 4-Epimerase

A necessary enzyme in the metabolism of galactose. It reversibly catalyzes the conversion of UDPglucose to UDPgalactose. NAD+ is an essential component for enzymatic activity. EC 5.1.3.2.

— U.S. National Library of Medicine

Nicotinamide adenine dinucleotide phosphate

Nicotinamide adenine dinucleotide phosphate

Nicotinamide adenine dinucleotide phosphate, abbreviated NADP+ or, in older notation, TPN, is a coenzyme used in anabolic reactions, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent. NADPH is the reduced form of NADP+. NADP+ differs from NAD+ in the presence of an additional phosphate group on the 2' position of the ribose ring that carries the adenine moiety.

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Fructuronate Reductase

Fructuronate Reductase

An enzyme that catalyzes the reversible oxidation of mannonate to fructuronate in the presence of NAD. Also reduces D-tagaturonate to D-altronate. EC 1.1.1.57.

— U.S. National Library of Medicine

MAŤO

MAŤO

The Maťo was an 8-bit personal computer produced in the former Czechoslovakia by Štátny majetok Závadka š.p., Závadka nad Hronom. Their primary goal was to produce a personal computer as cheaply as possible, and therefore it was also sold as a self-assembly kit. It was basically modified PMD 85, but without backward compatibility. This, combined with its late arrival to the market, made the MAŤO a commercial failure.

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3-Isopropylmalate Dehydrogenase

3-Isopropylmalate Dehydrogenase

An NAD+ dependent enzyme that catalyzes the oxidation of 3-carboxy-2-hydroxy-4-methylpentanoate to 3-carboxy-4-methyl-2-oxopentanoate. It is involved in the biosynthesis of VALINE; LEUCINE; and ISOLEUCINE.

— U.S. National Library of Medicine

Sirtuin 3

Sirtuin 3

A sirtuin family member found primarily in MITOCHONDRIA. It is a multifunctional enzyme that contains a NAD-dependent deacetylase activity that is specific for HISTONES and a mono-ADP-ribosyltransferase activity.

— U.S. National Library of Medicine

Dihydrouracil Dehydrogenase (NAD+)

Dihydrouracil Dehydrogenase (NAD+)

An enzyme that catalyzes the oxidation of 5,6-dihydrouracil to URACIL using NAD as a cofactor. This enzyme also plays a role in the catabolism of the antimetabolite 5-FLUOROURACIL.

— U.S. National Library of Medicine

Aldehyde Dehydrogenase

Aldehyde Dehydrogenase

An enzyme that oxidizes an aldehyde in the presence of NAD+ and water to an acid and NADH. This enzyme was formerly classified as EC 1.1.1.70.

— U.S. National Library of Medicine

Sirtuin 2

Sirtuin 2

A sirtuin family member found primarily in the CYTOPLASM. It is a multifunctional enzyme that contains a NAD-dependent deacetylase activity that is specific for HISTONES and a mono-ADP-ribosyltransferase activity.

— U.S. National Library of Medicine

Glutamate Dehydrogenase

Glutamate Dehydrogenase

An enzyme that catalyzes the conversion of L-glutamate and water to 2-oxoglutarate and NH3 in the presence of NAD+. (From Enzyme Nomenclature, 1992) EC 1.4.1.2.

— U.S. National Library of Medicine

L-Lactate Dehydrogenase

L-Lactate Dehydrogenase

A tetrameric enzyme that, along with the coenzyme NAD+, catalyzes the interconversion of LACTATE and PYRUVATE. In vertebrates, genes for three different subunits (LDH-A, LDH-B and LDH-C) exist.

— U.S. National Library of Medicine

Hydroxymethylglutaryl-CoA Reductases, NAD-Dependent

Hydroxymethylglutaryl-CoA Reductases, NAD-Dependent

Specific hydroxymethylglutaryl CoA reductases that utilize the cofactor NAD. This class of enzymes performs a catabolic role in microorganisms such as Pseudomonas mevalonii where it oxidatively acetylates MEVALONIC ACID to form 3-HYDROXY-3-METHYLGLUTARYL-COENZYME A and NADH.

— U.S. National Library of Medicine

Carbohydrate dehydrogenase

Carbohydrate dehydrogenase

Carbohydrate dehydrogenases are a group of dehydrogenase enzymes that occur in many organisms and facilitate the conversion from a carbohydrate to an aldehyde, lactone, or ketose. An example includes L-gulonolactone oxidase. They are categorized under EC number 1.1. More specifically, they are in three subcodes: 1, 2, and 99, categorized as follows: ⁕EC 1.1.1 With NAD or NADP as acceptor ⁕EC 1.1.2 With a cytochrome as acceptor ⁕EC 1.1.99 With other acceptors

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Kynureninase

Kynureninase

Kynureninase or L-Kynurenine hydrolase is a PLP dependent enzyme that catalyses the cleavage of kynurenine into anthranilic acid. It can also act on 3hKyn and some other-alanines. Humans express one kynureninase enzyme that is encoded by the KYNU gene located on chromosome 2. KYNU is part of the pathway for the catabolism of Trp and the biosynthesis of NAD cofactors from tryptophan. Kynureninase catalyzes the following reaction: ⁕L-kynurenine + H2O = anthranilate + L-alanine

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zeta-Crystallins

zeta-Crystallins

A group of crystallins that have been found in the lens (LENS, CRYSTALLINE) of certain species of VERTEBRATES including GUINEA PIGS; CAMELS; and LLAMAS. They are inactivated forms of NAD(P)H DEHYDROGENASE (QUINONE).

— U.S. National Library of Medicine

D-Xylulose Reductase

D-Xylulose Reductase

An enzyme that plays a role in the PENTOSES and GLUCURONATES interconversion pathway by catalyzing the oxidation of XYLITOL to D-xylulose. This enzyme has been found to be specific for NAD+.

— U.S. National Library of Medicine

Xanthine Dehydrogenase

Xanthine Dehydrogenase

An enzyme that catalyzes the oxidation of XANTHINE in the presence of NAD+ to form URIC ACID and NADH. It acts also on a variety of other purines and aldehydes.

— U.S. National Library of Medicine

Glutamate Synthase (NADH)

Glutamate Synthase (NADH)

A FLAVOPROTEIN enzyme for AMMONIA assimilation in BACTERIA, microorganisms and PLANTS. It catalyzes the oxidation of 2 molecules of L-GLUTAMATE to generate L-GLUTAMINE and 2-oxoglutarate in the presence of NAD+.

— U.S. National Library of Medicine

Dihydrodipicolinate Reductase

Dihydrodipicolinate Reductase

An enzyme that catalyzes the oxidation of 2,3,4,5-tetrahydrodipicolinate to 2,3-dihydrodipicolinate using NAD(P)+ as a cofactor. It is found in BACTERIA and higher plants involved in the biosynthesis of DIAMINOPIMELIC ACID and LYSINE.

— U.S. National Library of Medicine

Poly(ADP-ribose) Polymerases

Poly(ADP-ribose) Polymerases

Enzymes that catalyze the transfer of multiple ADP-RIBOSE groups from nicotinamide-adenine dinucleotide (NAD) onto protein targets, thus building up a linear or branched homopolymer of repeating ADP-ribose units i.e., POLY ADENOSINE DIPHOSPHATE RIBOSE.

— U.S. National Library of Medicine

1-Pyrroline-5-Carboxylate Dehydrogenase

1-Pyrroline-5-Carboxylate Dehydrogenase

An enzyme that catalyzes the oxidation of 1-pyrroline-5-carboxylate to L-GLUTAMATE in the presence of NAD. Defects in the enzyme are the cause of hyperprolinemia II.

— U.S. National Library of Medicine

Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)

Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)

An NAD-dependent enzyme that catalyzes the oxidation of acyl-[acyl-carrier protein] to trans-2,3-dehydroacyl-[acyl-carrier protein]. It has a preference for acyl groups with a carbon chain length between 4 to 16.

— U.S. National Library of Medicine

Torna County

Torna County

Torna is the name of a historic administrative county of the Kingdom of Hungary. It was located in present-day southeastern Slovakia and northern Hungary; today Turňa is only an informal designation of the corresponding territory in Slovakia. The initially large county was one of the original counties in the Kingdom of Hungary, but was gradually reduced to a territory corresponding to a small territory around the Turňa River. The capital of the county was Turňa Castle, later the town of Turňa nad Bodvou. From 1785–1790, 1848–1859, and ultimately in 1882 it was merged with the county Abov to form the county Abaúj-Torna.

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Antigens, CD38

Antigens, CD38

A bifunctional enzyme that catalyzes the synthesis and HYDROLYSIS of CYCLIC ADP-RIBOSE (cADPR) from NAD+ to ADP-RIBOSE. It is a cell surface molecule which is predominantly expressed on LYMPHOID CELLS and MYELOID CELLS.

— U.S. National Library of Medicine

Progesterone Reductase

Progesterone Reductase

An enzyme that catalyzes the reduction of a 3 beta-hydroxy-delta(5)-steroid to 3-oxo-delta(4)-steroid in the presence of NAD. It converts pregnenolone to progesterone and dehydroepiandrosterone to androstenedione. EC 1.1.1.145.

— U.S. National Library of Medicine

Niacin

Niacin

A water-soluble vitamin of the B complex occurring in various animal and plant tissues. It is required by the body for the formation of coenzymes NAD and NADP. It has PELLAGRA-curative, vasodilating, and antilipemic properties.

— U.S. National Library of Medicine

Leucine Dehydrogenase

Leucine Dehydrogenase

An octameric enzyme belonging to the superfamily of amino acid dehydrogenases. Leucine dehydrogenase catalyzes the reversible oxidative deamination of L-LEUCINE, to 4-methyl-2-oxopentanoate (2-ketoisocaproate) and AMMONIA, with the corresponding reduction of the cofactor NAD+.

— U.S. National Library of Medicine

Methylmalonate-Semialdehyde Dehydrogenase (Acylating)

Methylmalonate-Semialdehyde Dehydrogenase (Acylating)

An enzyme that plays a role in the VALINE; LEUCINE; and ISOLEUCINE catabolic pathways by catalyzing the oxidation of 2-methyl-3-oxopropanate to propanoyl-CoA using NAD+ as a coenzyme. Methylmalonate semialdehyde dehydrogenase deficiency is characterized by elevated BETA-ALANINE and 3-hydropropionic acid.

— U.S. National Library of Medicine

11-beta-Hydroxysteroid Dehydrogenase Type 1

11-beta-Hydroxysteroid Dehydrogenase Type 1

A low-affinity 11 beta-hydroxysteroid dehydrogenase found in a variety of tissues, most notably in LIVER; LUNG; ADIPOSE TISSUE; vascular tissue; OVARY; and the CENTRAL NERVOUS SYSTEM. The enzyme acts reversibly and can use either NAD or NADP as cofactors.

— U.S. National Library of Medicine

Alcohol dehydrogenase

Alcohol dehydrogenase

Alcohol dehydrogenases are a group of dehydrogenase enzymes that occur in many organisms and facilitate the interconversion between alcohols and aldehydes or ketones with the reduction of nicotinamide adenine dinucleotide. In humans and many other animals, they serve to break down alcohols that otherwise are toxic, and they also participate in generation of useful aldehyde, ketone, or alcohol groups during biosynthesis of various metabolites. In yeast, plants, and many bacteria, some alcohol dehydrogenases catalyze the opposite reaction as part of fermentation to ensure a constant supply of NAD+.

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Alcohol Oxidoreductases

Alcohol Oxidoreductases

A subclass of enzymes which includes all dehydrogenases acting on primary and secondary alcohols as well as hemiacetals. They are further classified according to the acceptor which can be NAD+ or NADP+ (subclass 1.1.1), cytochrome (1.1.2), oxygen (1.1.3), quinone (1.1.5), or another acceptor (1.1.99).

— U.S. National Library of Medicine

Prephenate Dehydrogenase

Prephenate Dehydrogenase

An enzyme that catalyzes the conversion of prephenate to p-hydroxyphenylpyruvate in the presence of NAD. In the enteric bacteria, this enzyme also possesses chorismate mutase activity, thereby catalyzing the first two steps in the biosynthesis of tyrosine. EC 1.3.1.12.

— U.S. National Library of Medicine

Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)

Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)

An NAD-dependent glyceraldehyde-3-phosphate dehydrogenase found in the cytosol of eucaryotes. It catalyses the dehydrogenation and phosphorylation of GLYCERALDEHYDE 3-PHOSPHATE to 3-phospho-D-glyceroyl phosphate, which is an important step in the GLYCOLYSIS pathway.

— U.S. National Library of Medicine

Nitrite Reductase (NAD(P)H)

Nitrite Reductase (NAD(P)H)

An enzyme found primarily in BACTERIA and FUNGI that catalyzes the oxidation of ammonium hydroxide to nitrite. It is an iron-sulfur HEME; FLAVOPROTEIN containing siroheme and can utilize both NAD and NADP as cofactors. This enzyme was formerly classified as EC 1.6.6.4.

— U.S. National Library of Medicine

Adenosine Diphosphate Ribose

Adenosine Diphosphate Ribose

An ester formed between the aldehydic carbon of RIBOSE and the terminal phosphate of ADENOSINE DIPHOSPHATE. It is produced by the hydrolysis of nicotinamide-adenine dinucleotide (NAD) by a variety of enzymes, some of which transfer an ADP-ribosyl group to target proteins.

— U.S. National Library of Medicine

Retinal Dehydrogenase

Retinal Dehydrogenase

A metalloflavoprotein enzyme involved the metabolism of VITAMIN A, this enzyme catalyzes the oxidation of RETINAL to RETINOIC ACID, using both NAD+ and FAD coenzymes. It also acts on both the 11-trans- and 13-cis-forms of RETINAL.

— U.S. National Library of Medicine

DNA Ligases

DNA Ligases

Poly(deoxyribonucleotide):poly(deoxyribonucleotide)ligases. Enzymes that catalyze the joining of preformed deoxyribonucleotides in phosphodiester linkage during genetic processes during repair of a single-stranded break in duplex DNA. The class includes both EC 6.5.1.1 (ATP) and EC 6.5.1.2 (NAD).

— U.S. National Library of Medicine

Nicotinamide Phosphoribosyltransferase

Nicotinamide Phosphoribosyltransferase

An enzyme that catalyzes the formation of nicotinamide mononucleotide (NMN) from nicotinamide and 5-phosphoribosyl-1-pyrophosphate, the rate-limiting step in the biosynthesis of the NAD coenzyme. It is also known as a growth factor for early B-LYMPHOCYTES, or an ADIPOKINE with insulin-mimetic effects (visfatin).

— U.S. National Library of Medicine

15-Oxoprostaglandin 13-Reductase

15-Oxoprostaglandin 13-Reductase

(5Z)-(15S)-11 alpha-Hydroxy-9,15-dioxoprostanoate:NAD(P)+ delta(13)-oxidoreductase. An enzyme active in prostaglandin E and F catabolism. It catalyzes the reduction of the double bond at the 13-14 position of the 15-ketoprostaglandins and uses NADPH as cofactor. EC 1.3.1.48.

— U.S. National Library of Medicine

Ethionamide

Ethionamide

Ethionamide is an antibiotic used in the treatment of tuberculosis. It was discovered in 1956. Ethionamide works to induce expression of EthA, a NAD derivative which is toxic to the bacteria. The resistance mechanism of this drug is through EthR, resistance is common. Therefore, EthR inhibitors are of great interest. It is a prodrug and as a thioamide, it is used in regimens to treat multi-drug-resistant and extensively drug-resistant tuberculosis. It has been proposed for use in combination with gatifloxacin. The action may be through disruption of mycolic acid.

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Annonacin

Annonacin

Annonacin is a chemical found in some fruits such as the custard apple and Sour Sop. It is a member of the class of compounds known as acetogenins. Recent reports have shown that regular consumption in rats caused brain lesions consistent with Parkinson's disease. Along with other acetogenins, annonacin is reported to block mitochondrial complex I, which is responsible for the conversion of NADH to NAD+ and the build-up of a proton gradient over the mitochondrial inner membrane. This effectively disables a cell's ability to generate ATP via an oxidative pathway, ultimately forcing a cell into apoptosis or necrosis.

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Alcohol Dehydrogenase

Alcohol Dehydrogenase

A zinc-containing enzyme which oxidizes primary and secondary alcohols or hemiacetals in the presence of NAD. In alcoholic fermentation, it catalyzes the final step of reducing an aldehyde to an alcohol in the presence of NADH and hydrogen.

— U.S. National Library of Medicine

NAD

NAD

A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)

— U.S. National Library of Medicine

Aryl Hydrocarbon Hydroxylases

Aryl Hydrocarbon Hydroxylases

A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.

— U.S. National Library of Medicine

Nitrate Reductase (NADPH)

Nitrate Reductase (NADPH)

An enzyme that catalyzes the oxidation of nitrite to nitrate in the presence of NADP+. It is a FLAVOPROTEIN that contains IRON and MOLYBDENUM. This enzyme was formerly classified as EC 1.6.6.3 and should not be confused with the enzyme NITRATE REDUCTASE (NAD(P)H).

— U.S. National Library of Medicine

3-Hydroxyacyl CoA Dehydrogenases

3-Hydroxyacyl CoA Dehydrogenases

Enzymes that reversibly catalyze the oxidation of a 3-hydroxyacyl CoA to 3-ketoacyl CoA in the presence of NAD. They are key enzymes in the oxidation of fatty acids and in mitochondrial fatty acid synthesis. EC 1.1.1.35.

— U.S. National Library of Medicine

Niacinamide

Niacinamide

An important compound functioning as a component of the coenzyme NAD. Its primary significance is in the prevention and/or cure of blacktongue and PELLAGRA. Most animals cannot manufacture this compound in amounts sufficient to prevent nutritional deficiency and it therefore must be supplemented through dietary intake.

— U.S. National Library of Medicine

Succinate-Semialdehyde Dehydrogenase

Succinate-Semialdehyde Dehydrogenase

An enzyme that plays a role in the GLUTAMATE and butanoate metabolism pathways by catalyzing the oxidation of succinate semialdehyde to SUCCINATE using NAD+ as a coenzyme. Deficiency of this enzyme, causes 4-hydroxybutyricaciduria, a rare inborn error in the metabolism of the neurotransmitter 4-aminobutyric acid (GABA).

— U.S. National Library of Medicine

NAD+ Nucleosidase

NAD+ Nucleosidase

An enzyme that catalyzes the hydrolysis of nicotinamide adenine dinucleotide (NAD) to NICOTINAMIDE and ADENOSINE DIPHOSPHATE RIBOSE. Some are extracellular (ectoenzymes).The enzyme from some sources also catalyses the hydrolysis of nicotinamide adenine dinucleotide phosphate (NADP).

— U.S. National Library of Medicine

Estradiol Dehydrogenases

Estradiol Dehydrogenases

Enzymes that catalyze the oxidation of estradiol at the 17-hydroxyl group in the presence of NAD+ or NADP+ to yield estrone and NADH or NADPH. The 17-hydroxyl group can be in the alpha- or beta-configuration. EC 1.1.1.62

— U.S. National Library of Medicine

3-alpha-Hydroxysteroid Dehydrogenase (B-Specific)

3-alpha-Hydroxysteroid Dehydrogenase (B-Specific)

A 3-hydroxysteroid dehydrogenase which catalyzes the reversible reduction of the active androgen, DIHYDROTESTOSTERONE to 5 ALPHA-ANDROSTANE-3 ALPHA,17 BETA-DIOL. It also has activity towards other 3-alpha-hydroxysteroids and on 9-, 11- and 15- hydroxyprostaglandins. The enzyme is B-specific in reference to the orientation of reduced NAD or NADPH.

— U.S. National Library of Medicine

Nitrate Reductase (NADH)

Nitrate Reductase (NADH)

An NAD-dependent enzyme that catalyzes the oxidation of nitrite to nitrate. It is a FLAVOPROTEIN that contains IRON and MOLYBDENUM and is involved in the first step of nitrate assimilation in PLANTS; FUNGI; and BACTERIA. It was formerly classified as EC 1.6.6.1.

— U.S. National Library of Medicine

Warsan

Warsan

Warsan is a locality in Dubai, United Arab Emirates. Warsan is an industrial neighbourhood of Dubai, bordering Al Warqaa to the north and Nad Al Sheba to the west. Warsan is subdivided into two localities — Warsan 1 and Warsan 2. The community is sparsely populated and is predominantly industrial, with the Dubai Sewage and Treatment Plant located in it. The new development, Dubai International City, will occupy much of the community. Other landmarks in the locality include Desert Palm Dubai, Al Aweer Power Station and Warsan Lake. Warsan is bounded to the north by route E 44 and to the west by route E 311.

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NADH Dehydrogenase

NADH Dehydrogenase

A flavoprotein and iron sulfur-containing oxidoreductase that catalyzes the oxidation of NADH to NAD. In eukaryotes the enzyme can be found as a component of mitochondrial electron transport complex I. Under experimental conditions the enzyme can use CYTOCHROME C GROUP as the reducing cofactor. The enzyme was formerly listed as EC 1.6.2.1.

— U.S. National Library of Medicine

Glutamate synthase

Glutamate synthase

In enzymology, a glutamate synthase (NADPH) is an enzyme that catalyzes the chemical reaction++ Thus, the four substrates of this enzyme are L-glutamine, 2-oxoglutarate, NADPH, and H+, whereas the two products are L-glutamate and NADP+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH2 group of donors with NAD+ or NADP+ as acceptor. This enzyme participates in glutamate metabolism and nitrogen metabolism. It has 5 cofactors: FAD, Iron, FMN, Sulfur, and Iron-sulfur. It occurs in bacteria and plants but not animals, and is important as it provides glutamate for the glutamine synthetase reaction.

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Glycine Dehydrogenase

Glycine Dehydrogenase

An oxidoreductase that catalyzes the oxidative DEAMINATION of GLYCINE to glyoxylate and AMMONIA in the presence of NAD. In BACTERIA lacking transaminating pathways the enzyme can act in the reverse direction to synthesize glycine from glyoxylate and ammonia and NADH.

— U.S. National Library of Medicine

L-Iditol 2-Dehydrogenase

L-Iditol 2-Dehydrogenase

An alcohol oxidoreductase which catalyzes the oxidation of L-iditol to L-sorbose in the presence of NAD. It also acts on D-glucitol to form D-fructose. It also acts on other closely related sugar alcohols to form the corresponding sugar. EC 1.1.1.14

— U.S. National Library of Medicine

Alanine Dehydrogenase

Alanine Dehydrogenase

An NAD-dependent enzyme that catalyzes the reversible DEAMINATION of L-ALANINE to PYRUVATE and AMMONIA. The enzyme is needed for growth when ALANINE is the sole CARBON or NITROGEN source. It may also play a role in CELL WALL synthesis because L-ALANINE is an important constituent of the PEPTIDOGLYCAN layer.

— U.S. National Library of Medicine

11-beta-Hydroxysteroid Dehydrogenase Type 2

11-beta-Hydroxysteroid Dehydrogenase Type 2

An high-affinity, NAD-dependent 11-beta-hydroxysteroid dehydrogenase that acts unidirectionally to catalyze the dehydrogenation of CORTISOL to CORTISONE. It is found predominantly in mineralocorticoid target tissues such as the KIDNEY; COLON; SWEAT GLANDS; and the PLACENTA. Absence of the enzyme leads to a fatal form of childhood hypertension termed, APPARENT MINERALOCORTICOID EXCESS SYNDROME.

— U.S. National Library of Medicine

Histone Deacetylases

Histone Deacetylases

Deacetylases that remove N-acetyl groups from amino side chains of the amino acids of HISTONES. The enzyme family can be divided into at least three structurally-defined subclasses. Class I and class II deacetylases utilize a zinc-dependent mechanism. The sirtuin histone deacetylases belong to class III and are NAD-dependent enzymes.

— U.S. National Library of Medicine

Glyceraldehyde-3-Phosphate Dehydrogenases

Glyceraldehyde-3-Phosphate Dehydrogenases

Enzymes that catalyze the dehydrogenation of GLYCERALDEHYDE 3-PHOSPHATE. Several types of glyceraldehyde-3-phosphate-dehydrogenase exist including phosphorylating and non-phosphorylating varieties and ones that transfer hydrogen to NADP and ones that transfer hydrogen to NAD.

— U.S. National Library of Medicine

Nitrate Reductase (NAD(P)H)

Nitrate Reductase (NAD(P)H)

An iron-sulfur and MOLYBDENUM containing FLAVOPROTEIN that catalyzes the oxidation of nitrite to nitrate. This enzyme can use either NAD or NADP as cofactors. It is a key enzyme that is involved in the first step of nitrate assimilation in PLANTS; FUNGI; and BACTERIA. This enzyme was formerly classified as EC 1.6.6.2.

— U.S. National Library of Medicine

ADP-ribosyl Cyclase

ADP-ribosyl Cyclase

A membrane-bound or cytosolic enzyme that catalyzes the synthesis of CYCLIC ADP-RIBOSE (cADPR) from nicotinamide adenine dinucleotide (NAD). This enzyme generally catalyzes the hydrolysis of cADPR to ADP-RIBOSE, as well, and sometimes the synthesis of cyclic ADP-ribose 2' phosphate (2'-P-cADPR) from NADP.

— U.S. National Library of Medicine

Laski, Warsaw West County

Laski, Warsaw West County

Laski is a village in Poland, in Masovian Voivodship, to the west of Warsaw, in the commune of Izabelin. It is located at the southern border of the Kampinos Forest and is a notable resort, with 1,600 permanent inhabitants. The village is notable for its resort, hospital and schools for blind people run by Towarzystwo Opieki nad Ociemniałymi and the Franciscan friars. In addition, a shelter for lone mothers run by Towarzystwo Pomocy im. Adama Chmielowskiego is located there. Near the blinded institute a wooden chapel is located, one of the most notable architectural monuments of the area. There is also a small World War II cemetery and a civilian cemetery, a final resting place of many Polish famous artists, among them are writers Antoni Słonimski and Jerzy Zawieyski.

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Pyrroline Carboxylate Reductases

Pyrroline Carboxylate Reductases

A group of enzymes that catalyze the reduction of 1-pyrroline carboxylate to proline in the presence of NAD(P)H. Includes both the 2-oxidoreductase (EC 1.5.1.1) and the 5-oxidoreductase (EC 1.5.1.2). The former also reduces 1-piperidine-2-carboxylate to pipecolate and the latter also reduces 1-pyrroline-3-hydroxy-5-carboxylate to hydroxyproline.

— U.S. National Library of Medicine

Liberec

Liberec

Liberec is a city in the Czech Republic. Located on the Lusatian Neisse and surrounded by the Jizera Mountains and Ještěd-Kozákov Ridge, it is the fifth-largest city in the Czech Republic. Settled by German and Flemish migrants since the 14th century until their expulsion after World War II, Liberec was once home to a thriving textile industry and hence nicknamed the "Manchester of Bohemia". For many Czechs, Liberec is mostly associated with the city's dominant Ještěd Tower. Since the end of the 19th century, the city has been a conurbation with the suburb of Vratislavice and the neighboring town of Jablonec nad Nisou. Therefore the total area with suburbs encompasses 150,000 inhabitants. This makes Liberec the third-largest city in Bohemia after Prague and Pilsen.

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NADH, NADPH Oxidoreductases

NADH, NADPH Oxidoreductases

A group of oxidoreductases that act on NADH or NADPH. In general, enzymes using NADH or NADPH to reduce a substrate are classified according to the reverse reaction, in which NAD+ or NADP+ is formally regarded as an acceptor. This subclass includes only those enzymes in which some other redox carrier is the acceptor. (Enzyme Nomenclature, 1992, p100) EC 1.6.

— U.S. National Library of Medicine

Flavin mononucleotide

Flavin mononucleotide

Flavin mononucleotide, or riboflavin-5′-phosphate, is a biomolecule produced from riboflavin by the enzyme riboflavin kinase and functions as prosthetic group of various oxidoreductases including NADH dehydrogenase as well as cofactor in biological blue-light photo receptors. During the catalytic cycle, a reversible interconversion of the oxidized, semiquinone and reduced forms occurs in the various oxidoreductases. FMN is a stronger oxidizing agent than NAD and is particularly useful because it can take part in both one- and two-electron transfers. In its role as blue-light photo receptor, FMN stands out from the 'conventional' photo receptors as the signaling state and not an E/Z isomerization. It is the principal form in which riboflavin is found in cells and tissues. It requires more energy to produce, but is more soluble than riboflavin.

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Malate dehydrogenase

Malate dehydrogenase

Malate dehydrogenase is an enzyme that reversibly catalyzes the oxidation of malate to oxaloacetate using the reduction of NAD+ to NADH. This reaction is part of many metabolic pathways, including the citric acid cycle. Other malate dehydrogenases, which have other EC numbers and catalyze other reactions oxidizing malate, have qualified names like malate dehydrogenase. Malate dehydrogenase is also involved in gluconeogenesis, the synthesis of glucose from smaller molecules. Pyruvate in the mitochondria is acted upon by pyruvate carboxylase to form oxaloacetate, a citric acid cycle intermediate. In order to get the oxaloacetate out of the mitochondria, malate dehydrogenase reduces it to malate, and it then traverses the inner mitochondrial membrane. Once in the cytosol, the malate is oxidized back to oxaloacetate by cytosolic malate dehydrogenase. Finally, phosphoenolpyruvate carboxykinase converts oxaloacetate to phosphoenolpyruvate.

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Lusatian Neisse

Lusatian Neisse

The Lusatian Neisse is a 252 km long river in Central Europe. It rises in the Jizera Mountains near Nová Ves nad Nisou, Czech Republic, reaching the tripoint with Poland and Germany at Zittau after 54 km, and later forming the Polish-German border for a length of 198 km. The Lusatian Neisse is a left-bank tributary of the river Oder, into which it flows between Neißemünde-Ratzdorf and Kosarzyn north of the towns of Guben and Gubin. According to the 1945 Potsdam Agreement in the aftermath of World War II, the river became part of the Polish western border with Germany. Being the longest and most notable of the three rivers named Neisse or Nysa, it is simply referred to as the Nysa or Neisse. An older Polish variant, no longer used, was Nissa.

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NADP Transhydrogenase

NADP Transhydrogenase

An enzyme present in the mitochondrial membrane of animals and in microorganisms. In the presence of energy (ATP) it catalyzes reversibly the reduction of NAD by NADPH to yield NADP and NADH. This reaction permits the utilization of the reducing properties of NADPH by the respiratory chain and in the reverse direction it allows the reduction of NADP for biosynthetic purposes. EC 1.6.1.1.

— U.S. National Library of Medicine

ADP Ribose Transferases

ADP Ribose Transferases

Enzymes that transfer the ADP-RIBOSE group of NAD or NADP to proteins or other small molecules. Transfer of ADP-ribose to water (i.e., hydrolysis) is catalyzed by the NADASES. The mono(ADP-ribose)transferases transfer a single ADP-ribose. POLY(ADP-RIBOSE) POLYMERASES transfer multiple units of ADP-ribose to protein targets, building POLY ADENOSINE DIPHOSPHATE RIBOSE in linear or branched chains.

— U.S. National Library of Medicine

Silent Information Regulator Proteins, Saccharomyces cerevisiae

Silent Information Regulator Proteins, Saccharomyces cerevisiae

A set of nuclear proteins in SACCHAROMYCES CEREVISIAE that are required for the transcriptional repression of the silent mating type loci. They mediate the formation of silenced CHROMATIN and repress both transcription and recombination at other loci as well. They are comprised of 4 non-homologous, interacting proteins, Sir1p, Sir2p, Sir3p, and Sir4p. Sir2p, an NAD-dependent HISTONE DEACETYLASE, is the founding member of the family of SIRTUINS.

— U.S. National Library of Medicine

Electron transport chain

Electron transport chain

An electron transport chain couples electron transfer between an electron donor and an electron acceptor with the transfer of H+ ions across a membrane. The resulting electrochemical proton gradient is used to generate chemical energy in the form of adenosine triphosphate. Electron transport chains are the cellular mechanisms used for extracting energy from sunlight in photosynthesis and also from redox reactions, such as the oxidation of sugars. In chloroplasts, light drives the conversion of water to oxygen and NADP+ to NADPH with transfer of H+ ions across chloroplast membranes. In mitochondria, it is the conversion of oxygen to water, NADH to NAD+ and succinate to fumarate that are required to generate the proton gradient. Electron transport chains are major sites of premature electron leakage to oxygen, generating superoxide and potentially resulting in increased oxidative stress.

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Amphibolic

Amphibolic

The term amphibolic is used to describe a biochemical pathway that involves both catabolism and anabolism. This term was proposed by B.Davis in 1961 to emphasise the dual metabolic role of such pathway. The citric acid cycle is a good example of amphibolic pathway. The first reaction of the cycle, in which oxaloacetate condenses with acetate to form citrate is typically anabolic. The next few reactions, which are intramolecular rearrangements, produce isocitrate. The following two reactions are typically catabolic. COO is lost in each step and succinate is produced. There is an interesting and critical difference in the coenzymes used in catabolic and anabolic pathways; in catabolism NAD+ serves as an oxidizing agent when it is reduced to NADH. Whereas in anabolism the coenzyme NADPH serves as the reducing agent and is converted to its oxidized form NADP+.

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Nicotinamide

Nicotinamide

Nicotinamide, also known as niacinamide and nicotinic acid amide, is the amide of nicotinic acid. Nicotinamide is a water-soluble vitamin and is part of the vitamin B group. Nicotinic acid, also known as niacin, is converted to nicotinamide in vivo, and, though the two are identical in their vitamin functions, nicotinamide does not have the same pharmacological and toxic effects of niacin, which occur incidental to niacin's conversion. Thus nicotinamide does not reduce cholesterol or cause flushing, although nicotinamide may be toxic to the liver at doses exceeding 3 g/day for adults. In cells, niacin is incorporated into nicotinamide adenine dinucleotide and nicotinamide adenine dinucleotide phosphate, although the pathways for nicotinamide and nicotinic acid are very similar. NAD+ and NADP+ are coenzymes in a wide variety of enzymatic oxidation-reduction reactions. It's produced by the aqueous aminolysis of 3-cyanopyridine and subsequent crystallization.

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Isocitrate Dehydrogenase

Isocitrate Dehydrogenase

An enzyme of the oxidoreductase class that catalyzes the conversion of isocitrate and NAD+ to yield 2-ketoglutarate, carbon dioxide, and NADH. It occurs in cell mitochondria. The enzyme requires Mg2+, Mn2+; it is activated by ADP, citrate, and Ca2+, and inhibited by NADH, NADPH, and ATP. The reaction is the key rate-limiting step of the citric acid (tricarboxylic) cycle. (From Dorland, 27th ed) (The NADP+ enzyme is EC 1.1.1.42.) EC 1.1.1.41.

— U.S. National Library of Medicine

Formate Dehydrogenases

Formate Dehydrogenases

Flavoproteins that catalyze reversibly the reduction of carbon dioxide to formate. Many compounds can act as acceptors, but the only physiologically active acceptor is NAD. The enzymes are active in the fermentation of sugars and other compounds to carbon dioxide and are the key enzymes in obtaining energy when bacteria are grown on formate as the main carbon source. They have been purified from bovine blood. EC 1.2.1.2.

— U.S. National Library of Medicine

Lactic acid fermentation

Lactic acid fermentation

Lactic acid fermentation is a biological process by which glucose, fructose, and sucrose are converted into cellular energy and the metabolite lactate. It is an anaerobic fermentation reaction that occurs in some bacteria and animal cells, such as muscle cells. If oxygen is present in the cell, many organisms will bypass fermentation and undergo cellular respiration; however, facultative anaerobic organisms will both ferment and undergo respiration in the presence of oxygen. Sometimes even when oxygen is present and aerobic metabolism is happening in the mitochondria, if pyruvate is building up faster than it can be metabolized, the fermentation will happen anyway. Lactate dehydrogenase catalyzes the interconversion of pyruvate and lactate with concomitant interconversion of NADH and NAD+. In homolactic fermentation, one molecule of glucose is ultimately converted to two molecules of lactic acid. Heterolactic fermentation, in contrast, yields carbon dioxide and ethanol in addition to lactic acid, in a process called the phosphoketolase pathway.

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Most

Most

Most is the capital city of the Most District, situated between the Central Bohemian Uplands and the Ore Mountains, approximately 77 km northwest of Prague along the Bílina River and southwest of Ústí nad Labem. The name Most means "bridge" in Czech. The town, which was named after the system of bridges that crossed the swamps in this area in the 10th century, is now mostly known for its heavy industry. The German name for Most is Brüx. Most lies at the heart of the northern Bohemian lignite-mining region and serves as an important industrial railway junction. During the latter half of the 20th century, Most was considered to be one of the most polluted Coal mining towns and in communist Czechoslovakia. Most's other industries includes textile, ceramics, steel, and chemicals. Foreign mining operations continue to operate in the area in the 21st century. Some surrounding villages are planned to be abandoned due to surface mining. However environmental conditions have improved in recent years around Most, in particular the growing of apples and grape vines has developed.

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152mm SpGH DANA

152mm SpGH DANA

The Dělo Automobilní Nabíjené Automaticky, also known as Samohybná Kanónová Húfnica vzor 77 was designed by Konštrukta Trenčín and built by ZTS Dubnica nad Váhom in the former Czechoslovakia as the first wheeled 152 mm self-propelled artillery gun to enter service. It was introduced in the 1970s. It is based on a modified 8x8 Tatra 813 chassis with excellent cross-country mobility. Currently it is in service with the Czech Republic, Libya, Poland, Georgia and Slovakia. Wheeled vehicles have the advantage of being cheaper to build and easier to maintain with greater mobility. Tire pressure can be regulated to allow good mobility off-road and there is power-assisted steering on the front four wheels. It lowers 3 hydraulic stabilizers into the ground prior to firing, and has a roof mounted crane to assist with ammunition loading. The crew of the DANA consists of the driver and commander sitting in the front cabin, the gunner and loader operator are on the left side of the turret, the ammo handler is on the right side turret.

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Sudetenland

Sudetenland

The Sudetenland is the German name to refer to those northern, southwest, and western areas of Czechoslovakia which were inhabited mostly by German speakers, specifically the border districts of Bohemia, Moravia, and those parts of Silesia located within Czechoslovakia. A proposed 1938 referendum to show what proportion of the Sudetenland's residents would claim a German ethnic background did not take place, following Adolf Hitler's demands at the Munich Agreement. The name is derived from that of the Sudetes mountains – featuring in Ptolemy's 2nd-century Geography as Sudeti montes – which run along the northern Czech border as far as Silesia and contemporary Poland, although it encompassed areas well beyond those mountains. The word Sudetenland came into existence in the early 20th century, and only came to prominence after the First World War. The German-speaking inhabitants of the region were then called Sudeten Germans. Previously, they were known variously as German Bohemians and German Moravians. The German minority in Slovakia, the Carpathian Germans, are not, however, included in any of these ethnic categories. Parts of the current Czech regions of Karlovy Vary, Liberec, Olomouc, Moravia-Silesia and Ústí nad Labem are situated within the former Sudetenland.

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Citric acid cycle

Citric acid cycle

The citric acid cycle — also known as the tricarboxylic acid cycle, or the Krebs cycle. — is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidization of acetate derived from carbohydrates, fats and proteins into carbon dioxide. In addition, the cycle provides precursors including certain amino acids as well as the reducing agent NADH that is used in numerous biochemical reactions. Its central importance to many biochemical pathways suggests that it was one of the earliest established components of cellular metabolism and may have originated abiogenically. The name of this metabolic pathway is derived from citric acid that is first consumed and then regenerated by this sequence of reactions to complete the cycle. In addition, the cycle consumes acetate and water, reduces NAD+ to NADH, and produces carbon dioxide. The NADH generated by the TCA cycle is fed into the oxidative phosphorylation pathway. The net result of these two closely linked pathways is the oxidation of nutrients to produce usable energy in the form of ATP. In eukaryotic cells, the citric acid cycle occurs in the matrix of the mitochondrion. Bacteria also use the TCA cycle to generate energy, but since they lack mitochondria, the reaction sequence is performed in the cytosol with the proton gradient for ATP production being across the plasma membrane rather than the inner membrane of the mitochondrion.

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Smrk

Smrk

Smrk is a massif and a mountain in the Moravian-Silesian Beskids range in the Czech Republic. With a height of 1,276 m it is the second highest summit of the range after Lysá hora. Its Northern slope steeply rises from the surrounding lowlands and is separated from the rest of the mountains by the deep Ostravice River and Čeladenka river valleys; in the South it merges in the lower Zadní hory area. Although its name suggests differently it was originally covered mainly in Beech and Fir forests, with a higher Spruce share closer to the summit. During the industrial revolution in the region under the mountains in the 18th and 19th centuries when many ironworks were established, with a center in Frýdlant nad Ostravicí, there was a high demand for firewood and the original forests were felled out and replaced by secondary Spruce plantations. These were heavily damaged by industrial fall-out from the Ostrava region also because non-native Spruce varieties, which were not well adapted to the local climate, were planted there. Thus everyone coming to Smrk from North will see a mountain stripped of trees in its upper parts. Other slopes were not so heavily damaged and are still forested in most places. Especially in the Čeladenka river valley there any many stretches of preserved or newly planted Beech trees.

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Wachlarz

Wachlarz

Wachlarz was a Polish World War II resistance organization formed by the Armia Krajowa for sabotage duties behind the German Eastern Front, outside of the Polish borders. Its commanders were Lt.Col. Jan Włodarkiewicz and Lt.Col. Adam Remigiusz Grocholski Originally formed in 1941, shortly after the outbreak of the Nazi-Soviet war, the organization was subordinate to Związek Walki Zbrojnej and bore the cryptnonym 18, later changed to 27. The final name, Wachlarz, was a result of the subdivision of the organization onto several branches, each trying to spread its influence from certain portions of the Polish border deep into the Soviet territory. There were five different sectors of Wachlarz, each acting independently and formed along several main supply lines of the German war machine: ⁕Lwów-Tarnopol-Zhmerynka-Dnipropetrovsk ⁕Równe-Zhytomir-Kiev ⁕Brześć nad Bugiem-Pińsk-Homel ⁕Lida-Minsk-Borisov-Orsha ⁕Wilno-Daugavpils-Polotsk The main aim of the organization was to prepare reconnaissance, intelligence, sabotage and diversion between the Eastern Front and the pre-war Polish borders, from the Baltic Sea to southern Ukraine. By cutting the supply lines and disruptung troop movement, the organization was to be prepared to cut the German lines during the planned all-national uprising. The aim was to separate the German army from its supply depots and allow for the Polish underground forces to liberate Poland while the Germans in the USSR are crushed both from the east and the west.

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Cofactor

Cofactor

A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity. These proteins are commonly enzymes, and cofactors can be considered "helper molecules" that assist in biochemical transformations. Cofactors can be classified depending on how tightly they bind to an enzyme, with loosely bound cofactors termed coenzymes and tightly bound cofactors termed prosthetic groups. Some sources also limit the use of the term "cofactor" to inorganic substances. An inactive enzyme, without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is the holoenzyme. Some enzymes or enzyme complexes require several cofactors. For example, the multienzyme complex pyruvate dehydrogenase at the junction of glycolysis and the citric acid cycle requires five organic cofactors and one metal ion: loosely bound thiamine pyrophosphate, covalently bound lipoamide and flavin adenine dinucleotide, and the cosubstrates nicotinamide adenine dinucleotide and coenzyme A, and a metal ion. Organic cofactors are often vitamins or are made from vitamins. Many contain the nucleotide adenosine monophosphate as part of their structures, such as ATP, coenzyme A, FAD, and NAD+. This common structure may reflect a common evolutionary origin as part of ribozymes in an ancient RNA world. It has been suggested that the AMP part of the molecule can be considered a kind of "handle" by which the enzyme can "grasp" the coenzyme to switch it between different catalytic centers.

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Chlorobium

Chlorobium

Chlorobium is a genus of green sulfur bacteria. They are photolithotrophic oxidizers of sulfur and most notably utilise a noncyclic electron transport chain to reduce NAD+. Hydrogen sulfide is used as an electron source and carbon dioxide its carbon source. Chlorobium species exhibit a dark green color; in a Winogradsky column, the green layer often observed is composed of Chlorobium. This genus lives in strictly anaerobic conditions below the surface of a body of water, commonly the anaerobic zone of a eutrophic lake. Chlorobium aggregatum is a species which exists in a symbiotic relationship with a colorless, nonphotosynthetic bacteria. This species looks like a bundle of green bacteria, attached to a central rod-like cell which can move around with a flagellum. The green, outer bacteria use light to oxidize sulfide into sulfate. The inner cell, which is not able to perform photosynthesis, reduces the sulfate into sulfide. These bacteria divide in unison, giving the structure a multicellular appearance which is highly unusual in bacteria. Chlorobium species are thought to have played an important part in mass extinction events on Earth. If the oceans turn anoxic then Chlorobium would be able to out compete other photosynthetic life. They would produce huge quantities of methane and hydrogen sulfide which would cause global warming and acid rain. This would have huge consequences for other oceanic organisms and also for terrestrial organisms. Evidence for abundant Chlorobium populations is provided by chemical fossils found in sediments deposited at the Cretaceous mass extinction.

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