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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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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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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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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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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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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 Chemistry and Biomimetics of PQQ
1989Chemical simulation of redox functions of PQQ-containing enzymes was studied to clarify the roles of coenzyme PQQ. Thus catalytic oxidations of amines, amino acids, glucose, alcohols, thiols, and nitroalkanes with PQQ were investigated from the stand point of organic chemistry and effective redox system was found as oxidase models.
Yoshiki Ohshiro, Shinobu Itoh
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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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Identification and Quantification of PQQ
1989PQQ can occur in free form, as a C5-addition compound, as a condensation product with amino acids (e.g. an oxazole) and in an extractable or covalently bound form. Free, underivatized PQQ can be quantified by several chromatographic methods and biological assays. However, alternative analytical procedures had to be developed for the other cases. The so-
Robert A. van der Meer +2 more
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