The Role of Remote Flavin Adenine Dinucleotide Pieces in the Oxidative Decarboxylation Catalyzed by Salicylate Hydroxylase

2021 ◽  
pp. 105561
Author(s):  
Mozart S. Pereira ◽  
Simara S. de Araújo ◽  
Ronaldo A. P. Nagem ◽  
John P. Richard ◽  
Tiago A. S. Brandão
Keyword(s):  
Flavin Adenine Dinucleotide ◽  
Oxidative Decarboxylation

scholarly journals PSXIV-19 Effect of alpha-lipoic acid on productive parameters and ruminal VFA profile in sheep

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 437-438
Author(s):  
Carolina Robles ◽  
Laura Gonzáles Davalos ◽  
Ofelia Mora ◽  
Yesmin Hermanadez ◽  
Armando Shimada ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Lipoic Acid ◽  
Insulin Receptors ◽  
Daily Weight Gain ◽  
Oxidative Decarboxylation ◽  
Alpha Lipoic Acid ◽  
Randomized Design ◽  
Keto Acids ◽  
Mechanism Research

Abstract Alpha lipoic acid (LA) is a potent nutritional antioxidant. It is a derivate of octanoic acid containing a cyclic disulfide bond. An LA complex with lysine-lipoamide, functions as a co-factor in the mitochondrial dehydrogenase that catalyzes the oxidative decarboxylation of α-keto acids. In this reaction, LA is reduced to dihydrolipoic acid (DHLA), which interacts with reactive oxygen species, and LA can also inactivate free radicals. Another important role of DHLA is in signal transduction by activating insulin receptors, which causes glucose transporters translocation from cytoplasm to the cell surface. Due to its potential antioxidant effect at ruminal level, the aim of this study was to evaluate the effect of fed LA on productive parameters, ruminal fatty volatile fatty acid (VFA) concentration and blood glucose of sheep. Sixty-four, two-months-old, crossbred lambs were penned in groups of four, divided into four treatments: 0, 40, 80, and 120 ppm LA in diet. During 84 days, every 28 days on two consecutive days, animals were weighed (to determine average daily weight gain, DWG), blood and ruminal fluid were taken for glucose and VFA quantification, respectively. All variables were analyzed in a completely randomized design. DWG was statistically higher in those animals receiving 80 ppm (250 g) as compared to the rest (200, 188, 180 g for 120, 40, 0 ppm, respectively) (P < 0.0001). No differences in blood glucose or ruminal VFA were found (P > 0.1). LA could improve the productive performance of sheep; however, it would be necessary to study the role of LA and its effects on the ruminal microbiome and its action mechanism. Research support by Project PAPIIT-UNAM IN211518

scholarly journals A Regulatory Role of NAD Redox Status on Flavin Cofactor Homeostasis inS. cerevisiaeMitochondria

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
Teresa Anna Giancaspero ◽  
Vittoria Locato ◽  
Maria Barile
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Nicotinamide Adenine Dinucleotide ◽  
Flavin Adenine Dinucleotide ◽  
Redox Balance ◽  
Redox Status ◽  
Cellular Redox ◽  
Isolated Mitochondria ◽  
Nudix Hydrolases ◽  
Order Of Magnitude

Flavin adenine dinucleotide (FAD) and nicotinamide adenine dinucleotide (NAD) are two redox cofactors of pivotal importance for mitochondrial functionality and cellular redox balance. Despite their relevance, the mechanism by which intramitochondrial NAD(H) and FAD levels are maintained remains quite unclear inSaccharomyces cerevisiae. We investigated here the ability of isolated mitochondria to degrade externally added FAD and NAD (in both its reduced and oxidized forms). A set of kinetic experiments demonstrated that mitochondrial FAD and NAD(H) destroying enzymes are different from each other and from the already characterized NUDIX hydrolases. We studied here, in some detail, FAD pyrophosphatase (EC 3.6.1.18), which is inhibited by NAD+and NADH according to a noncompetitive inhibition, withKivalues that differ from each other by an order of magnitude. These findings, together with the ability of mitochondrial FAD pyrophosphatase to metabolize endogenous FAD, presumably deriving from mitochondrial holoflavoproteins destined to degradation, allow for proposing a novel possible role of mitochondrial NAD redox status in regulating FAD homeostasis and/or flavoprotein degradation inS. cerevisiae.

scholarly journals New Insight into the Role of the Calvin Cycle: Reutilization of CO2 Emitted through Sugar Degradation

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Rie Shimizu ◽  
Yudai Dempo ◽  
Yasumune Nakayama ◽  
Satoshi Nakamura ◽  
Takeshi Bamba ◽  
...  
Keyword(s):  
Ralstonia Eutropha ◽  
Calvin Cycle ◽  
Oxidative Decarboxylation ◽  
Carbon Yield ◽  
Efficient Utilization ◽  
Sugar Degradation ◽  
Biomass Resources ◽  
Insight Into ◽  
Reducing Equivalents

Abstract Ralstonia eutropha is a facultative chemolithoautotrophic bacterium that uses the Calvin–Benson–Bassham (CBB) cycle for CO2 fixation. This study showed that R. eutropha strain H16G incorporated 13CO2, emitted by the oxidative decarboxylation of [1-13C1]-glucose, into key metabolites of the CBB cycle and finally into poly(3-hydroxybutyrate) [P(3HB)] with up to 5.6% 13C abundance. The carbon yield of P(3HB) produced from glucose by the strain H16G was 1.2 times higher than that by the CBB cycle-inactivated mutants, in agreement with the possible fixation of CO2 estimated from the balance of energy and reducing equivalents through sugar degradation integrated with the CBB cycle. The results proved that the ‘gratuitously’ functional CBB cycle in R. eutropha under aerobic heterotrophic conditions participated in the reutilization of CO2 emitted during sugar degradation, leading to an advantage expressed as increased carbon yield of the storage compound. This is a new insight into the role of the CBB cycle and may be applicable for more efficient utilization of biomass resources.

scholarly journals FAD roles in glucose catalytic oxidation studied by multiphase flow of extractive electrospray ionization (MF-EESI) mass spectrometry

2018 ◽  
Vol 9 (3) ◽  
pp. 594-599 ◽  
Author(s):  
Yan Wang ◽  
Min Sun ◽  
Jinping Qiao ◽  
Jin Ouyang ◽  
Na Na
Keyword(s):  
Mass Spectrometry ◽  
Multiphase Flow ◽  
Electrospray Ionization ◽  
Catalytic Oxidation ◽  
Flavin Adenine Dinucleotide ◽  
Ionization Method ◽  
Oxidation Of Glucose

The role of the coenzyme flavin adenine dinucleotide (FAD) in the catalytic oxidation of glucose was elucidated by MS using a new extraction and ionization method.

scholarly journals Identification of Escherichia coli YgaF as an l-2-Hydroxyglutarate Oxidase

2008 ◽  
Vol 190 (11) ◽  
pp. 3793-3798 ◽  
Author(s):  
Efthalia Kalliri ◽  
Scott B. Mulrooney ◽  
Robert P. Hausinger
Keyword(s):  
Escherichia Coli ◽  
Unknown Function ◽  
Oxidase Activity ◽  
Flavin Adenine Dinucleotide ◽  
Reduction Potential ◽  
High Reduction ◽  
Very High

ABSTRACT YgaF, a protein of previously unknown function in Escherichia coli, was shown to possess noncovalently bound flavin adenine dinucleotide and to exhibit l-2-hydroxyglutarate oxidase activity. The inability of anaerobic, reduced enzyme to reverse the reaction by reducing the product α-ketoglutaric acid is explained by the very high reduction potential (+19 mV) of the bound cofactor. The likely role of this enzyme in the cell is to recover α-ketoglutarate mistakenly reduced by other enzymes or formed during growth on propionate. On the basis of the identified function, we propose that this gene be renamed lhgO.

Metabolic control exerted by the 2-oxoglutarate dehydrogenase reaction: a cross-kingdom comparison of the crossroad between energy production and nitrogen assimilation

2009 ◽  
Vol 422 (3) ◽  
pp. 405-421 ◽  
Author(s):  
Victoria I. Bunik ◽  
Alisdair R. Fernie
Keyword(s):  
Metabolic Control ◽  
Nitrogen Assimilation ◽  
Biological Systems ◽  
Wound Response ◽  
Metabolic Adaptation ◽  
Oxidative Decarboxylation ◽  
Dehydrogenase Reaction ◽  
Wide Range ◽  
The Impact

Mechanism-based inhibitors and both forward and reverse genetics have proved to be essential tools in revealing roles for specific enzymatic processes in cellular function. Here, we review experimental studies aimed at assessing the impact of OG (2-oxoglutarate) oxidative decarboxylation on basic cellular activities in a number of biological systems. After summarizing the catalytic and regulatory properties of the OGDHC (OG dehydrogenase complex), we describe the evidence that has been accrued on its cellular role. We demonstrate an essential role of this enzyme in metabolic control in a wide range of organisms. Targeting this enzyme in different cells and tissues, mainly by its specific inhibitors, effects changes in a number of basic functions, such as mitochondrial potential, tissue respiration, ROS (reactive oxygen species) production, nitrogen metabolism, glutamate signalling and survival, supporting the notion that the evolutionary conserved reaction of OG degradation is required for metabolic adaptation. In particular, regulation of OGDHC under stress conditions may be essential to overcome glutamate excitotoxicity in neurons or affect the wound response in plants. Thus, apart from its role in producing energy, the flux through OGDHC significantly affects nitrogen assimilation and amino acid metabolism, whereas the side reactions of OGDHC, such as ROS production and the carboligase reaction, have biological functions in signalling and glyoxylate utilization. Our current view on the role of OGDHC reaction in various processes within complex biological systems allows us a far greater fundamental understanding of metabolic regulation and also opens up new opportunities for us to address both biotechnological and medical challenges.

scholarly journals Role of XDHC in Molybdenum Cofactor Insertion into Xanthine Dehydrogenase of Rhodobacter capsulatus

1999 ◽  
Vol 181 (9) ◽  
pp. 2745-2751 ◽  
Author(s):  
Silke Leimkühler ◽  
Werner Klipp
Keyword(s):  
Flavin Adenine Dinucleotide ◽  
Rhodobacter Capsulatus ◽  
Strain Analysis ◽  
Transcriptional Regulator ◽  
Xanthine Dehydrogenase ◽  
Molybdenum Cofactor ◽  
Iron Sulfur Clusters ◽  
Iron Sulfur ◽  
A Subunit

ABSTRACT Rhodobacter capsulatus xanthine dehydrogenase (XDH) is composed of two subunits, XDHA and XDHB. Immediately downstream ofxdhB, a third gene was identified, designatedxdhC, which is cotranscribed with xdhAB. Interposon mutagenesis revealed that the xdhC gene product is required for XDH activity. However, XDHC is not a subunit of active XDH, which forms an α2β2 heterotetramer inR. capsulatus. It was shown that XDHC neither is a transcriptional regulator for xdh gene expression nor influences XDH stability. To analyze the function of XDHC for XDH inR. capsulatus, inactive XDH was purified from anxdhC mutant strain. Analysis of the molybdenum cofactor content of this enzyme demonstrated that in the absence of XDHC, no molybdopterin cofactor MPT is present in the XDHAB tetramer. In contrast, absorption spectra of inactive XDH isolated from thexdhC mutant revealed the presence of iron-sulfur clusters and flavin adenine dinucleotide, demonstrating that XDHC is not required for the insertion of these cofactors. The absence of MPT from XDH isolated from an xdhC mutant indicates that XDHC either acts as a specific MPT insertase or might be a specific chaperone facilitating the insertion of MPT and/or folding of XDH during or after cofactor insertion.

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