Results 171 to 180 of about 3,727 (217)
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The Biochemistry, Physiology and Genetics of PQQ and PQQ-containing Enzymes
1998Pyrrolo-quinoline quinone (PQQ) is the non-covalently bound prosthetic group of many quinoproteins catalysing reactions in the periplasm of Gram-negative bacteria. Most of these involve the oxidation of alcohols or aldose sugars. PQQ is formed by fusion of glutamate and tyrosine, but details of the biosynthetic pathway are not known; a polypeptide ...
P M, Goodwin, C, Anthony
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The Role of PQQ in K.aerogenes and Cloning of pqq Genes
1989Enterobacteriaceae transport glucose into the cell by means of the PEP-dependent carbohydrate phosphotransferase system (PTS). In Klebsiella aerogenes an alternative pathway exists involving a glucose dehydrogenase (GLD, facing the periplasm) which uses pyrroloquinoline quinone (PQQ) as cofactor and is linked to the respiratory chain. It probably plays
J. J. M. Meulenberg +3 more
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Pharmacological Application of PQQ
2020This chapter summarizes previous experimental data on pharmacological effects of Pyrroloquinoline quinone (PQQ) specifically with respect to acetaldehyde metabolism following ethanol loading to rats and the protective effects of PQQ against hepatotoxin-induced liver injury in rats and against hydrocortisone-induced cataract formation in chick embryos ...
Akiharu Watanabe +4 more
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Life Sciences, 1993
The effects of pyrroloquinoline quinone (PQQ) and PQQ-oxazole (PQQ-glycine adduct) on DNA synthesis were examined using cultured human fibroblasts. Confluent fibroblasts were cultured in serum-free Dulbecco's modified Eagle's media, and various concentrations of PQQ and PQQ-oxazole were added to the media.
Y, Naito +3 more
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The effects of pyrroloquinoline quinone (PQQ) and PQQ-oxazole (PQQ-glycine adduct) on DNA synthesis were examined using cultured human fibroblasts. Confluent fibroblasts were cultured in serum-free Dulbecco's modified Eagle's media, and various concentrations of PQQ and PQQ-oxazole were added to the media.
Y, Naito +3 more
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Analytical Biochemistry, 1996
Pyrroloquinoline quinone (PQQ) is a widely distributed redox-active cofactor and essential nutrient. For its detection in protein-free ultrafiltrates or dialysates, a highly sensitive amplification assay was developed on the basis of PQQ's ability to catalyze redox cycling at pH 10 in the presence of excess glycine, oxygen, and nitro blue tetrazolium ...
M A, Paz +4 more
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Pyrroloquinoline quinone (PQQ) is a widely distributed redox-active cofactor and essential nutrient. For its detection in protein-free ultrafiltrates or dialysates, a highly sensitive amplification assay was developed on the basis of PQQ's ability to catalyze redox cycling at pH 10 in the presence of excess glycine, oxygen, and nitro blue tetrazolium ...
M A, Paz +4 more
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2020
Pyrroloquinoline quinone (PQQ) biosynthesis is complicated by the fact that it is synthesized in the cytoplasm and must then find its way to the periplasm where the active enzyme/cofactor complex is assembled. Clearly the a-nitrogen of tyrosine was not randomized in PQQ, demonstrating that tyrosine, and not its requisite a-keto acid, is the precursor ...
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Pyrroloquinoline quinone (PQQ) biosynthesis is complicated by the fact that it is synthesized in the cytoplasm and must then find its way to the periplasm where the active enzyme/cofactor complex is assembled. Clearly the a-nitrogen of tyrosine was not randomized in PQQ, demonstrating that tyrosine, and not its requisite a-keto acid, is the precursor ...
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Journal of the American Chemical Society, 2004
Pyrroloquinoline quinone (PQQ) is a tricyclic o-quinone, which serves as a cofactor in several enzyme-catalyzed redox reactions in certain bacteria. PQQ is also important for human health, and its role as a vitamin in mammals has recently been suggested. Although much is known about the function of enzymes that use PQQ as cofactor, relatively little is
Olafur T, Magnusson +4 more
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Pyrroloquinoline quinone (PQQ) is a tricyclic o-quinone, which serves as a cofactor in several enzyme-catalyzed redox reactions in certain bacteria. PQQ is also important for human health, and its role as a vitamin in mammals has recently been suggested. Although much is known about the function of enzymes that use PQQ as cofactor, relatively little is
Olafur T, Magnusson +4 more
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The Biomedical Significance of PQQ
2020This chapter presents an overview of the biomedical significance of Pyrroloquinoline quinone (PQQ). It was first isolated from cultures of methylotrophic bacteria as an acetone adduct and its structure determined by X-ray diffraction and confirmed by organic synthesis. PQQ captures electrons from primary amines, catechols, catecholamines, ascorbic acid,
Mercedes A. Paz +2 more
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Oxidation of D-glucose by coenzyme PQQ: 1,2-enediolates as substrates for PQQ oxidation
Journal of the Chemical Society, Chemical Communications, 1987Studies on the oxidation of D-glucose and related substrates with coenzyme PQQ have established that 1,2-enediolates are efficient substrates for PQQ oxidation.
Shinobu Itoh +2 more
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Methoxatin (PQQ) in guinea-pig neutrophils
Free Radical Biology and Medicine, 1994PQQ, also called methoxatin, has been isolated from guinea-pig neutrophils. The organic cations diphenyleneiodonium (DPI) and diphenyliodonium (BPI) and the aromatic o-diamine 4,5-dimethylphenylenediamine (DIMPDA) sequester synthetic PQQ and inhibit its redox-cycling activity in a model system.
A, Bishop +3 more
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