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Pqq review

Mitsugu Akagawa, Masahiko Nakano, Kazuto Ikemoto
Pyrroloquinoline quinone (PQQ), an aromatic tricyclic o-quinone, was identified initially as a redox cofactor for bacterial dehydrogenases. Although PQQ is not biosynthesized in mammals, trace amounts of PQQ have been found in human and rat tissues because of its wide distribution in dietary sources. Importantly, nutritional studies in rodents have revealed that PQQ deficiency exhibits diverse systemic responses, including growth impairment, immune dysfunction, and abnormal reproductive performance. Although PQQ is not currently classified as a vitamin, PQQ has been implicated as an important nutrient in mammals...
2015: Bioscience, Biotechnology, and Biochemistry
Ye Li, Xue Li, Yixuan Zhang
2-keto-L-gulonate (2-KGA) is the key intermediate of vitamin C, which can be biosynthesized by Ketogulonigenium vulgare. There are five reactions related to 2-KGA metabolism, including: (1) Oxidation of D-sorbitol to L-sorbose; (2) Oxidation of L-sorbose to L-sorbosone; (3) Oxidation of L-sorbosone (Pyranose form) to 2-KGA; (4) Oxidation of L-sorbosone (Furanose form) to vitamin C, and (5) Reduction of 2-KGA to L-idonate. L-sorbose/L-sorbosone dehydrogenase (SSDH) is responsible for the reaction of 1 through 3, L-sorbose dehydrogenase (SDH) is responsible for the reaction of 2 and 3, L-sorbosone dehydrogenase (SNDH) is responsible for the reaction of 3 and 4, aldehyde dehydrogenase (ALDH) is responsible for the reaction of 3, 2-KGA reductase (2-KGR) is responsible for the reaction of 5...
October 4, 2014: Wei Sheng Wu Xue Bao, Acta Microbiologica Sinica
H S Misra, Y S Rajpurohit, N P Khairnar
Pyrroloquinoline-quinine (PQQ) was initially characterized as a redox cofactor for membrane-bound dehydrogenases in the bacterial system. Subsequently, PQQ was shown to be an antioxidant protecting the living cells from oxidative damage in vivo and the biomolecules from artificially produced reaction oxygen species in vitro. The presence of PQQ has been documented from different biological samples. It functions as a nutrient and vitamin for supporting the growth and protection of living cells under stress. Recently, the role of PQQ has also been shown as a bio-control agent for plant fungal pathogens, an inducer for proteins kinases involved in cellular differentiation of mammalian cells and as a redox sensor leading to development of biosensor...
June 2012: Journal of Biosciences
Miriam Rosenbaum, Federico Aulenta, Marianna Villano, Largus T Angenent
This review illuminates extracellular electron transfer mechanisms that may be involved in microbial bioelectrochemical systems with biocathodes. Microbially-catalyzed cathodes are evolving for new bioprocessing applications for waste(water) treatment, carbon dioxide fixation, chemical product formation, or bioremediation. Extracellular electron transfer processes in biological anodes, were the electrode serves as electron acceptor, have been widely studied. However, for biological cathodes the question remains: what are the biochemical mechanisms for the extracellular electron transfer from a cathode (electron donor) to a microorganism? This question was approached by not only analysing the literature on biocathodes, but also by investigating known extracellular microbial oxidation reactions in environmental processes...
January 2011: Bioresource Technology
Juan P Frias, Christine G Lim, John M Ellison, Carol M Montandon
OBJECTIVE: To assess the implications of falsely elevated glucose readings measured with glucose dehydrogenase pyrroloquinolinequinone (GDH-PQQ) test strips. RESEARCH DESIGN AND METHODS: We conducted a review of the Food and Drug Administration's Manufacturer and User Facility Device Experience database and medical literature for adverse events (AEs) associated with falsely elevated glucose readings with GDH-PQQ test strips in the presence of interfering sugars...
April 2010: Diabetes Care
Toshiharu Yakushi, Kazunobu Matsushita
Pyrroquinoline quinone-dependent alcohol dehydrogenase (PQQ-ADH) of acetic acid bacteria is a membrane-bound enzyme involved in the acetic acid fermentation by oxidizing ethanol to acetaldehyde coupling with reduction of membranous ubiquinone (Q), which is, in turn, re-oxidized by ubiquinol oxidase, reducing oxygen to water. PQQ-ADHs seem to have co-evolved with the organisms fitting to their own habitats. The enzyme consists of three subunits and has a pyrroloquinoline quinone, 4 heme c moieties, and a tightly bound Q as the electron transfer mediators...
May 2010: Applied Microbiology and Biotechnology
Jan Tkac, Juraj Svitel, Igor Vostiar, Marian Navratil, Peter Gemeiner
Although membrane-bound dehydrogenases isolated from Gluconobacter sp. (mainly PQQ-dependent alcohol and fructose dehydrogenase) have been used for preparing diverse forms of bioelectronic interfaces for almost 2 decades, it is not an easy task to interpret an electrochemical behaviour correctly. Recent discoveries regarding redox properties of membrane-bound dehydrogenases along with extensive investigations of direct electron transfer (DET) or direct bioelectrocatalysis with these enzymes are summarized in this review...
September 2009: Bioelectrochemistry
Ljiljana Fruk, Chi-Hsien Kuo, Eduardo Torres, Christof M Niemeyer
Many enzymes contain a nondiffusible organic cofactor, often termed a prosthetic group, which is located in the active site and essential for the catalytic activity of the enzyme. These cofactors can often be extracted from the protein to yield the respective apoenzyme, which can subsequently be reconstituted with an artificial analogue of the native cofactor. Nowadays a large variety of synthetic cofactors can be used for the reconstitution of apoenzymes and, thus, generate novel semisynthetic enzymes. This approach has been refined over the past decades to become a versatile tool of structural enzymology to elucidate structure-function relationships of enzymes...
2009: Angewandte Chemie
Tina Hölscher, Ute Schleyer, Marcel Merfort, Stephanie Bringer-Meyer, Helmut Görisch, Hermann Sahm
Gluconobacter oxydans is famous for its rapid and incomplete oxidation of a wide range of sugars and sugar alcohols. The organism is known for its efficient oxidation of D-glucose to D-gluconate, which can be further oxidized to two different keto-D-gluconates, 2-keto-D-gluconate and 5-keto-D-gluconate, as well as 2,5-di-keto-D-gluconate. For this oxidation chain and for further oxidation reactions, G. oxydans possesses a high number of membrane-bound dehydrogenases. In this review, we focus on the dehydrogenases involved in D-glucose oxidation and the products formed during this process...
2009: Journal of Molecular Microbiology and Biotechnology
Laura Masgrau, Jaswir Basran, Parvinder Hothi, Michael J Sutcliffe, Nigel S Scrutton
It is now widely accepted that substrate C-H bond breakage by quinoprotein enzymes occurs by quantum mechanical tunneling. This paradigm shift in the conceptual framework for these reactions away from semi-classical transition state theory (i.e., including zero-point energy but with no tunneling correction) has been driven over recent years by experimental studies of the temperature dependence of kinetic isotope effects for these reactions in the TTQ-dependent enzymes methylamine dehydrogenase and aromatic amine dehydrogenase, which produced observations also inconsistent with the simple Bell correction model of tunneling...
August 1, 2004: Archives of Biochemistry and Biophysics
Christopher Anthony
This review summarises our current understanding of two of the main types of quinoprotein dehydrogenase in which pyrroloquinoline quinone (PQQ) is the only prosthetic group. These are the soluble methanol dehydrogenase and the membrane glucose dehydrogenase (mGDH). The membrane GDH has an additional N-terminal domain by which it is tightly anchored to the membrane, and a periplasmic domain whose structure has been modelled on the X-ray structure of the alpha-subunit of MDH which contains PQQ in the active site...
August 1, 2004: Archives of Biochemistry and Biophysics
Franz R Krueger, Wolfgang Werther, Jochen Kissel, Erich R Schmid
The 'Cometary and Interstellar Dust Analyser' (CIDA) is a particle impact time-of-flight mass spectrometer onboard the NASA spacecraft STARDUST. A series of positive and negative ion mass spectra from the impact of (apparently) interstellar dust particles has been collected since 1999. In the meantime laboratory work has been performed to better understand the ion formation processes of organic grains impacting at those speeds (>15 km/s) and to relate them to some other ion formation methods. The key ion types were the negative ions, with some additional information from the positive ions...
2004: Rapid Communications in Mass Spectrometry: RCM
Mamoru Yamada, M D Elias, Kazunobu Matsushita, Catharina T Migita, Osao Adachi
Membrane-bound glucose dehydrogenase (mGDH) in Escherichia coli is one of the pivotal pyrroloquinoline quinone (PQQ)-containing quinoproteins coupled with the respiratory chain in the periplasmic oxidation of alcohols and sugars in Gram-negative bacteria. We compared mGDH with other PQQ-dependent quinoproteins in molecular structure and attempted to trace their evolutionary process. We also review the role of residues crucial for the catalytic reaction or for interacting with PQQ and discuss the functions of two distinct domains, radical formation in PQQ, and the presumed existence of bound quinone in mGDH...
April 11, 2003: Biochimica et Biophysica Acta
Christopher Anthony, Paul Williams
This is a review of recent work on methanol dehydrogenase (MDH), a pyrroloquinoline quinone (PQQ)-containing enzyme catalysing the oxidation of methanol to formaldehyde in methylotrophic bacteria. Although it is the most extensively studied of this class of dehydrogenases, it is only recently that there has been any consensus about its mechanism. This is partly due to recent structural studies on normal and mutant enzymes and partly due to more definitive work on the mechanism of related alcohol and glucose dehydrogenases...
April 11, 2003: Biochimica et Biophysica Acta
Andrew R Knaggs
This review covers the literature published during 2000 on the biosynthesis of compounds derived wholly or partly from intermediates on the shikimate pathway. Recent developments in the enzymology and genetics of the shikimate pathway arc also described. Enzymes involved in the biogenetic pathway to the aromatic amino acids are covered initially followed by sections dedicated to metabolites derived in some part from intermediates on the pathway. These include pyrrolnitrin. violacein. indole-3-acetic acid, coumarins, lignans, lignin, tannins, melanin, flavanoids, ubiquinone, TOPA quinone, PQQ, and tropanes...
February 2003: Natural Product Reports
Valdas Laurinavicius, Julija Razumiene, Bogumila Kurtinaitiene, Ingrida Lapenaite, Irina Bachmatova, Liucija Marcinkeviciene, Rolandas Meskys, Arunas Ramanavicius
This paper focuses on the use of PQQ-dependent enzymes (PQQ enzymes) in amperometrical biosensors and gives emphasis on their innovative designs and applications. The study covers some aspects in the evolution of biosensors based on PQQ enzymes. Main attention is focused on the electrochemical properties of PQQ enzymes as very promising materials for the formation of electrochemical biosensors. Immobilization approaches and redox mediators recently used in PQQ enzymes based biosensors are reviewed. The acceptance of polypyrrole as a very promising immobilization matrix for some PQQ enzymes is discussed...
January 2002: Bioelectrochemistry
C Anthony
This review summarises the characteristics, identification, and measurement of pyrroloquinoline quinone, the prosthetic group of bacterial quinoprotein dehydrogenases whose structures, mechanisms, and electron transport functions are described in detail. Type I alcohol dehydrogenase includes the "classic" methanol dehydrogenase; its x-ray structure and mechanism are discussed in detail. It is likely that its mechanism involves a direct hydride transfer rather than a mechanism involving a covalent adduct. The x-ray structure of a closely related ethanol dehydrogenase is also described...
October 2001: Antioxidants & Redox Signaling
T E Stites, A E Mitchell, R B Rucker
O-quinone cofactors derived from tyrosine and tryptophan are involved in novel biological reactions that range from oxidative deaminations to free-radical redox reactions. The formation of each of these cofactors appears to involve post-translational modifications of either tyrosine or tryptophan residues. The modifications result in cofactors, such as topaquinone (TPQ), tryptophan tryptophylquinone (TTQ), lysine tyrosylquinone (LTQ) or the copper-complexed cysteinyl-tyrosyl radical from metal-catalyzed reactions...
April 2000: Journal of Nutrition
W S McIntire
Research spurred by the discovery of pyrroloquinoline quinone (PPQ) in 1979 led to the discovery of four additional oxidation-reduction (redox) cofactors, all of which result from transmogrification of amino acyl side chains in respective enzymes. These cofactors are (a) topa quinone in copper-containing amine oxidases, enzymes found in nearly all forms of life, including human; (b) lysyl topa quinone of the copper protein lysyl oxidase, an enzyme required for proper cross-linking of collagen and elastin; (c) tryptophan tryptophylquinone of alkylamine dehydrogenases from gram-negative soil bacteria; and (d) the copper-complexed cysteinyltyrosyl radical of fungal galactose oxidase...
1998: Annual Review of Nutrition
C Anthony, M Ghosh
Bacterial methanol and glucose dehydrogenases containing a novel type of prosthetic group, subsequently identified as pyrrolo-quinoline quinone (PQQ), were first described about 30 years ago. Quinoproteins were originally defined as proteins containing PQQ but this definition has since been broadened to include those proteins containing other types of quinone-containing prosthetic groups, and the X-ray structures of representatives of each type of quinoprotein have recently been published. This review is mainly concerned with the structure and function of the PQQ-containing methanol dehydrogenase, whose structure has been determined at high resolution, and related proteins...
1998: Progress in Biophysics and Molecular Biology
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