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Sample records for 3-hydroxy-3-methyl glutaryl coenzyme

  1. Leoligin, the major lignan from Edelweiss, inhibits 3-hydroxy-3-methyl-glutaryl-CoA reductase and reduces cholesterol levels in ApoE-/- mice.

    PubMed

    Scharinger, Bernhard; Messner, Barbara; Türkcan, Adrian; Schuster, Daniela; Vuorinen, Anna; Pitterl, Florian; Heinz, Katharina; Arnhard, Kathrin; Laufer, Günther; Grimm, Michael; Stuppner, Hermann; Oberacher, Herbert; Eller, Philipp; Ritsch, Andreas; Bernhard, David

    2016-10-01

    The health benefit through the control of lipid levels in hyperlipidaemic individuals is evident from a large number of studies. The pharmacological options to achieve this goal shall be as specific and personalized as the reasons for and co-factors of hyperlipidaemia. It was the goal of this study to reveal the impact of leoligin on cholesterol levels and to define its mechanism of action. Oral application of leoligin in ApoE-/- mice led to significantly reduced total serum cholesterol levels and a reduction in postprandial blood glucose peak levels. In the absence of biochemical signs of toxicity, leoligin treatment resulted in reduced weight gain in mice. The effects of leoligin on serum cholesterol levels may be due to a direct inhibition of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR) by a unique, non-statin-like binding mode. Postprandial serum glucose peaks may be reduced by a mild peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonistic activity of leoligin. No effect on atherosclerotic plaque size was observed. As a non-toxic, cholesterol-, peak glucose-, and weight gain-lowering compound, leoligin continues to fulfil characteristics of a potential agent for the treatment of cardiovascular disease (CVD). The counterregulatory overexpression of hepatic HMGCR in leoligin treated animals possibly explains the missing permanent anti-atherosclerotic effect.

  2. Recombinant 3-Hydroxy 3-Methyl Glutaryl-CoA Reductase from Candida glabrata (Rec-CgHMGR) Obtained by Heterologous Expression, as a Novel Therapeutic Target Model for Testing Synthetic Drugs.

    PubMed

    Andrade-Pavón, Dulce; Cuevas-Hernández, Roberto I; Trujillo-Ferrara, José G; Hernández-Rodríguez, César; Ibarra, J Antonio; Villa-Tanaca, Lourdes

    2017-01-30

    The enzyme 3-hydroxy-3-methyl-glutaryl CoA reductase (HMGR) is a glycoprotein of the endoplasmic reticulum that participates in the mevalonate pathway, the precursor of cholesterol in human and ergosterol in fungi. This enzyme has three domains: transmembrane, binding, and soluble. In this study, we expressed and purified the soluble fraction of the HMGR enzyme from Candida glabrata (CgHMGR) in an Escherichia coli heterologous system and used it as a model for studying its inhibitory activity. The soluble fraction of CgHMGR was fused to the maltose binding protein (MBP), purified, and characterized. Optimal pH was 8.0, and its optimal temperature activity was 37 °C. The k m and V max for the HMG-CoA were 6.5 μM and 2.26 × 10(-3) μM min(-1), respectively. Recombinant CgHMGR was inhibited by simvastatin presenting an IC50 at 14.5 μM. In conclusion, our findings suggest that the recombinant HMGR version from C. glabrata may be used as a study model system for HMGR inhibitors such as statins and newly synthesized inhibitor compounds that might be used in the treatment of hypercholesterolemia or mycosis.

  3. Asian plantain (Plantago asiatica) essential oils suppress 3-hydroxy-3-methyl-glutaryl-co-enzyme A reductase expression in vitro and in vivo and show hypocholesterolaemic properties in mice.

    PubMed

    Chung, Mi Ja; Park, Kuen Woo; Kim, Kyoung Heon; Kim, Cheong-Tae; Baek, Jun Pill; Bang, Kyong-Hwan; Choi, Young-Mi; Lee, Sung-Joon

    2008-01-01

    Asian plantain (Plantago asiatica) essential oil (PAEO) contains multiple bioactive compounds, but its potential effects on lipid metabolism have not been examined. PAEO was found to be mostly composed of oxygenated monoterpenes, with linalool as the major component (82.5 %, w/w), measured using GC-MS. Incubation of 0-200 microg PAEO/ml with HepG2 cells for 24 h resulted in no significant toxicity. Incubation with 0.2 mg PAEO/ml altered the expression of LDL receptor (+83 %; P < 0.05) and 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase ( - 37 %; P < 0.05), as assessed using RT-PCR. LDL oxidation was markedly inhibited by PAEO treatment due to the prevalence of linalool compounds in PAEO. Oral administration of PAEO for 3 weeks in C57BL/6 mice significantly reduced plasma total cholesterol and TAG concentrations by 29 and 46 %, respectively. The mRNA (+58 %; P < 0.05), but not protein, levels of the LDL receptor were significantly higher, whereas both mRNA and protein levels of HMG-CoA reductase were significantly lower ( - 46 and - 11 %, respectively; P < 0.05) in the liver of PAEO-fed than of control mice. The mRNA levels of CYP7A1 were marginally reduced in HepG2 cells, but not in mouse liver after PAEO treatment. Thus, PAEO may have hypocholesterolaemic effects by altering the expression of HMG-CoA reductase. Reduced TAG and oxidised LDL may provide additional cardiovascular protective benefits.

  4. Use of hydroxy-methyl-glutaryl coenzyme A reductase inhibitors is associated with risk of lymphoid malignancies.

    PubMed

    Iwata, Hiroshi; Matsuo, Keitaro; Hara, Shigeo; Takeuchi, Kengo; Aoyama, Tomonori; Murashige, Naoko; Kanda, Yoshinobu; Mori, Shin-Ichiro; Suzuki, Risturo; Tachibana, Shintaro; Yamane, Masaaki; Odawara, Masato; Mutou, Yoshitomo; Kami, Masahiro

    2006-02-01

    It has been speculated that the use of hydroxy-methyl-glutaryl coenzyme A reductase inhibitors (statins) is associated with the risk of malignant diseases. Considering their immunosuppressive activities, malignant diseases that are associated with an immunosuppressive status seem feasible to examine the association. We therefore examined the association between statin use and development of lymphoid malignancies in a case-control study. Cases were 221 consecutive incident cases with histopathologically proven lymphoid malignancies (lymphoma and myeloma), hospitalized in the Department of Hematology of Toranomon Hospital (Tokyo, Japan) between 1995 and 2001. Two independent control groups, comprising 442 and 437 inpatients without malignancies from the Departments of Orthopedics and Otorhinolaryngology of the same hospital, were selected to test for consistency of association. Controls were matched individually with cases for age, sex and year of admission. Subject information, including statin use, was abstracted from medical records at the time of hospitalization. Strength of association was evaluated as an adjusted odds ratios (aOR) using a conditional logistic regression model. A higher frequency of statin use was found among patients with lymphoid malignancies in comparison with both orthopedic (aOR 2.11, 95% CI 1.20-3.69, P = 0.009) and otorhinolaryngology patients (aOR 2.59, 95% CI 1.45-4.65, P = 0.001), the significance being maintained when the two control groups were combined (aOR 2.24, 95% CI 1.37-3.66, P = 0.001). In conclusion, we observed an elevated risk of lymphoid malignancy with statin use among Japanese patients. Further evaluations in different populations are required to draw conclusions as to the carcinogenicity of lymphoid malignancies with statin use.

  5. Glutaryl-coenzyme A dehydrogenase from Geobacter metallireducens - interaction with electron transferring flavoprotein and kinetic basis of unidirectional catalysis.

    PubMed

    Estelmann, Sebastian; Boll, Matthias

    2014-11-01

    Glutaryl-CoA dehydrogenases (GDHs) are FAD containing acyl-CoA dehydrogenases that usually catalyze the dehydrogenation and decarboxylation of glutaryl-CoA to crotonyl-CoA with an electron transferring flavoprotein (ETF) acting as natural electron acceptor. In anaerobic bacteria, GDHs play an important role in the benzoyl-CoA degradation pathway of monocyclic aromatic compounds. In the present study, we identified, purified and characterized the benzoate-induced BamOP as the electron accepting ETF of GDH (BamM) from the Fe(III)-respiring Geobacter metallireducens. The BamOP heterodimer contained FAD and AMP as cofactors. In the absence of an artificial electron acceptor, at pH values above 8, the BamMOP-components catalyzed the expected glutaryl-CoA oxidation to crotonyl-CoA and CO2 ; however, at pH values below 7, the redox-neutral glutaryl-CoA conversion to butyryl-CoA and CO2 became the dominant reaction. This previously unknown, strictly ETF-dependent coupled glutaryl-CoA oxidation/crotonyl-CoA reduction activity was facilitated by an unexpected two-electron transfer between FAD(BamM) and FAD(BamOP) , as well as by the similar redox potentials of the two FAD cofactors in the substrate-bound state. The strict order of electron/proton transfer and C-C-cleavage events including transient charge-transfer complexes did not allow an energetic coupling of electron transfer and decarboxylation. This explains why it was difficult to release the glutaconyl-CoA intermediate from reduced GDH. Moreover, it provides a kinetic rational for the apparent inability of BamM to catalyze the reverse reductive crotonyl-CoA carboxylation, even under thermodynamically favourable conditions. For this reason reductive crotonyl-CoA carboxylation, a key reaction in C2-assimilation via the ethylmalonyl-CoA pathway, is accomplished by a different crotonyl-CoA carboxylase/reductase via a covalent NADPH/ene-adduct.

  6. Enhancement of fatty acid and cholesterol synthesis accompanied by enhanced biliary but not very-low-density lipoprotein lipid secretion following sustained pravastatin blockade of hydroxymethyl glutaryl coenzyme A reductase in rat liver.

    PubMed

    Carrella, M; Fong, L G; Loguercio, C; Del Piano, C

    1999-05-01

    A 3-week treatment of rats with pravastatin (PV) augmented biliary cholesterol and phospholipid output 3.6- and 2.2-fold over controls, while bile acid (BA) output and kinetics were unchanged. No major changes were detected in hepatic and serum cholesterol concentrations despite the PV inhibitory property on hydroxymethyl glutaryl coenzyme A (HMG CoA) reductase. To evaluate the mechanisms of this adaptive phenomenon, several parameters of hepatic lipid homeostasis were assessed. Biliary cholesterol changes could not be attributed to an increased influx of lipoprotein cholesterol to the liver and bile. Hepatic low-density lipoprotein (LDL) receptor content, as inferred from Western blot analysis, was unchanged, as was the biliary excretion of labeled cholesterol derived from chylomicron remnants. In vivo 3H2O-incorporation studies showed an 80% increase in hepatic cholesterol synthesis, evidence for bypass of the PV block. Remarkably, fatty acid synthesis was also stimulated twofold, providing substrate for hepatic triglycerides, which were slightly enhanced. However, serum triglycerides decreased 52% associated with a 22% decrease in hepatic very-low-density lipoprotein (VLDL) secretion. Thus, the biochemical adaptation following PV treatment produces complex alterations in hepatic lipid metabolism. An enhanced supply of newly synthesized cholesterol and fatty acids in association with a limited VLDL secretion rate augments the biliary lipid secretion pathway in this experimental model.

  7. Gene structure and mutations of glutaryl-coenzyme A dehydrogenase: Impaired association of enzyme subunits that is due to an A421V substitution causes glutaric acidemia type I in the Amish

    SciTech Connect

    Biery, B.J.; Stein, D.E.; Goodman, S.I.

    1996-11-01

    The structure of the human glutaryl coenzyme A dehydrogenase (GCD) gene was determined to contain 11 exons and to span {approximately}7 kb. Fibroblast DNA from 64 unrelated glutaric academia type I (GA1) patients was screened for mutations by PCR amplification and analysis of SSCP. Fragments with altered electrophoretic mobility were subcloned and sequenced to detect mutations that caused GA1. This report describes the structure of the GCD gene, as well as point mutations and polymorphisms found in 7 of its 11 exons. Several mutations were found in more than one patient, but no one prevalent mutation was detected in the general population. As expected from pedigree analysis, a single mutant allele causes GA1 in the Old Order Amish of Lancaster County, Pennsylvania. Several mutations have been expressed in Escherichia coli, and all produce diminished enzyme activity. Reduced activity in GCD encoded by the A421V mutation in the Amish may be due to impaired association of enzyme subunits. 13 refs., 5 figs., 3 tabs.

  8. High Dose Atorvastatin Decreases Cellular Markers of Immune Activation Without Affecting HIV-1 RNA Levels: Results of a Double-Blind Randomized Placebo Controlled Clinical Trial

    DTIC Science & Technology

    2011-02-15

    cholesterol -depleting agents, such as 3-hydroxy- 3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase inhibitors ( statins ), reduces HIV-1 particle production [5...Furthermore, virions derived from cholesterol -depleted cells demonstrate reduced infectivity in vitro [5]. In addition, statins have dem- onstrated...studies revealed that substantial statin - induced decreases in cholesterol resulted in declines in HIV-1 production [5]. We therefore chose the highest

  9. Essential oil of Pinus koraiensis leaves exerts antihyperlipidemic effects via up-regulation of low-density lipoprotein receptor and inhibition of acyl-coenzyme A: cholesterol acyltransferase.

    PubMed

    Kim, Ji-Hyun; Lee, Hyo-Jung; Jeong, Soo-Jin; Lee, Min-Ho; Kim, Sung-Hoon

    2012-09-01

    Hyperlipidemia is an important factor to induce metabolic syndrome such as obesity, diabetes and cardiovascular diseases. Recently, some antihyperlipidemic agents from herbal medicines have been in the spotlight in the medical science field. Thus, the present study evaluated the antihyperlipidemic activities of the essential oil from the leaves of Pinus koraiensis SIEB (EOPK) that has been used as a folk remedy for heart disease. The reverse transcription polymerase chain reaction (RT-PCR) revealed that EOPK up-regulated low density lipoprotein receptor (LDLR) at the mRNA level as well as negatively suppressed the expression of sterol regulatory element-binding protein (SREBP)-1c, SREBP-2, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR), fatty acid synthase (FAS) and glycerol-3-phosphate acyltransferase (GPAT) involved in lipid metabolism in HepG2 cells. Also, western blotting showed that EOPK activated LDLR and attenuated the expression of FAS at the protein level in the cells. Consistently, EOPK significantly inhibited the level of human acylcoenzyme A: cholesterol acyltransferase (hACAT)1 and 2 and reduced the low-density lipoprotein (LDL) oxidation activity. Furthermore, chromatography-mass spectrometry (GC-MS) analysis showed that EOPK, an essential oil mixture, contained camphene (21.11%), d-limonene (21.01%), α-pinene (16.74%) and borneol (11.52%). Overall, the findings suggest that EOPK can be a potent pharmaceutical agent for the prevention and treatment of hyperlipidemia.

  10. Pediatric Statin Administration: Navigating a Frontier with Limited Data

    PubMed Central

    Abdel-Rahman, Susan M.

    2016-01-01

    Increasingly, children and adolescents with dyslipidemia qualify for pharmacologic intervention. As they are for adults, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) are the mainstay of pediatric dyslipidemia treatment when lifestyle modifications have failed. Despite the overall success of these drugs, the magnitude of variability in dose-exposure-response profiles contributes to adverse events and treatment failure. In children, the cause of treatment failures remains unclear. This review describes the updated guidelines for screening and management of pediatric dyslipidemia and statin disposition pathway to assist the provider in recognizing scenarios where alterations in dosage may be warranted to meet patients' specific needs. PMID:27877092

  11. Potentiated cytotoxic effects of statins and ajoene in murine melanoma cells.

    PubMed

    Ledezma, Eliades; Wittig, Olga; Alonso, Jose; Cardier, Jose E

    2009-04-01

    Because statins and ajoene inhibit the 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, we evaluated the hypothesis that the cytotoxic effect of these compounds may be potentiated when both are used in combination on tumor cells. We showed that cotreatment of the murine melanoma B16F10 cell with statins (atorvastatin and pravastatin) and ajoene, all at nontoxic doses, dramatically increased their cytotoxicity. B16F10 cell death induced by statins, but not by ajoene, was prevented by mevalonate and geranylgeranylpyrophosphate. To our knowledge, this is the first report that the combination of statins and ajoene, which alters the mevalonate pathway, might potentiate their cytotoxic effects on tumor cells.

  12. Mung bean decreases plasma cholesterol by up-regulation of CYP7A1.

    PubMed

    Yao, Yang; Hao, Liu; Shi, Zhenxing; Wang, Lixia; Cheng, Xuzhen; Wang, Suhua; Ren, Guixing

    2014-06-01

    Our results affirmed that supplementation of 1 or 2% mung bean could decrease plasma total cholesterol and triacylglycerol level. Mung bean increased mRNA 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase. Most importantly, mung bean increased not only the protein level of cholesterol-7α-hydroxylase (CYP7A1) but also mRNA CYP7A1. It was concluded that the hypocholesterolemic activity of mung bean was most probable mediated by enhancement of bile acid excretion and up-regulation of CYP7A1.

  13. Different effect of simvastatin and atorvastatin on key enzymes involved in VLDL synthesis and catabolism in high fat/cholesterol fed rabbits

    PubMed Central

    Verd, Joan C; Peris, Cristina; Alegret, Marta; Díaz, Cristina; Hernández, Gonzalo; Vázquez, Manuel; Adzet, Tomás; Laguna, Juan C; Sánchez, Rosa M

    1999-01-01

    The effects of atorvastatin (3 mg kg−1) and simvastatin (3 mg kg−1) on hepatic enzyme activities involved in very low density lipoprotein metabolism were studied in coconut oil/cholesterol fed rabbits.Plasma cholesterol and triglyceride levels increased 19 and 4 fold, respectively, after 7 weeks of feeding.Treatment with statins during the last 4 weeks of feeding abolished the progression of hypercholesterolaemia and reduced plasma triglyceride levels.3-Hydroxy-3-methyl-glutaryl Coenzyme A reductase, acyl-coenzyme A:cholesterol acyltransferase, phosphatidate phosphohydrolase and diacylglycerol acyltransferase activities were not affected by drug treatment. Accordingly, hepatic free cholesterol, cholesteryl ester and triglyceride content were not modified.Simvastatin treatment caused an increase (72%) in lipoprotein lipase activity without affecting hepatic lipase activity.Atorvastatin caused a reduction in hepatic phospholipid content and a compensatory increase in CTP:phosphocholine cytidylyl transferase activity.The results presented in this study suggest that, besides the inhibitory effect on 3-hydroxy-3-methyl-glutaryl Coenzyme A reductase, simvastatin and atorvastatin may have additional effects that contribute to their triglyceride-lowering ability. PMID:10455299

  14. Proteome-wide Lysine Glutarylation Profiling of the Mycobacterium tuberculosis H37Rv.

    PubMed

    Xie, Longxiang; Wang, Guirong; Yu, Zhaoxiao; Zhou, Mingliang; Li, Qiming; Huang, Hairong; Xie, Jianping

    2016-04-01

    Lysine glutarylation, a new protein posttranslational modification (PTM), was recently identified and characterized in both prokaryotic and eukaryotic cells. To explore the distribution of lysine glutarylation in Mycobacterium tuberculsosis, by using a comprehensive method combining the immune affinity peptide enrichment by the glutaryl-lysine antibody with LC-MS, we finally identified 41 glutarylation sites in 24 glutarylated proteins from M. tuberculosis. These glutarylated proteins are involved in various cellular functions such as translation and metabolism and exhibit diverse subcellular localizations. Three common glutarylated proteins including 50S ribosomal protein L7/L12, elongation factor Tu, and dihydrolipoamide succinyltransferase are shared between Escherichia coli and M. tuberculosis. Moreover, comparison with other PTMs characterized in M. tuberculosis, 15 glutarylated proteins, are found to be both acetylated and succinylated. Notably, several stress-response-associated proteins including HspX are glutarylated. Our data provide the first analysis of M. tuberculosis lysine glutarylated proteins. Further studies on the role of the glutarylated proteins will unveil the molecular mechanisms of glutarylation underlying M. tuberculosis physiology and pathogenesis.

  15. Different effect of simvastatin and atorvastatin on key enzymes involved in VLDL synthesis and catabolism in high fat/cholesterol fed rabbits.

    PubMed

    Verd, J C; Peris, C; Alegret, M; Díaz, C; Hernández, G; Vázquez, M; Adzet, T; Laguna, J C; Sánchez, R M

    1999-07-01

    The effects of atorvastatin (3 mg kg(-1)) and simvastatin (3 mg kg(-1)) on hepatic enzyme activities involved in very low density lipoprotein metabolism were studied in coconut oil/cholesterol fed rabbits. Plasma cholesterol and triglyceride levels increased 19 and 4 fold, respectively, after 7 weeks of feeding. Treatment with statins during the last 4 weeks of feeding abolished the progression of hypercholesterolaemia and reduced plasma triglyceride levels. 3-Hydroxy-3-methyl-glutaryl Coenzyme A reductase, acylcoenzyme A:cholesterol acyltransferase, phosphatidate phosphohydrolase and diacylglycerol acyltransferase activities were not affected by drug treatment. Accordingly, hepatic free cholesterol, cholesteryl ester and triglyceride content were not modified. Simvastatin treatment caused an increase (72%) in lipoprotein lipase activity without affecting hepatic lipase activity. Atorvastatin caused a reduction in hepatic phospholipid content and a compensatory increase in CTP:phosphocholine cytidylyl transferase activity. The results presented in this study suggest that, besides the inhibitory effect on 3-hydroxy-3-methyl-glutaryl Coenzyme A reductase, simvastatin and atorvastatin may have additional effects that contribute to their triglyceride-lowering ability.

  16. Metabolic Regulation by Lysine Malonylation, Succinylation, and Glutarylation*

    PubMed Central

    Hirschey, Matthew D.; Zhao, Yingming

    2015-01-01

    Protein acetylation is a well-studied regulatory mechanism for several cellular processes, ranging from gene expression to metabolism. Recent discoveries of new post-translational modifications, including malonylation, succinylation, and glutarylation, have expanded our understanding of the types of modifications found on proteins. These three acidic lysine modifications are structurally similar but have the potential to regulate different proteins in different pathways. The deacylase sirtuin 5 (SIRT5) catalyzes the removal of these modifications from a wide range of proteins in different subcellular compartments. Here, we review these new modifications, their regulation by SIRT5, and their emerging role in cellular regulation and diseases. PMID:25717114

  17. Coenzymes as coribozymes.

    PubMed

    Jadhav, Vasant R; Yarus, Michael

    2002-09-01

    Coenzymes are small organic molecules that supply a varied set of reactive groups to protein enzymes, thereby diversifying catalysis beyond the chemistries of amino acid sidechains. As RNA structures begin with a more limited chemical diversity than proteins, it seems likely that RNA enzymes would also use functional groups from other molecules to support a complex RNA world metabolism. In fact, ribonucleotide moieties in many coenzymes have long been thought to be surviving vestiges of covalently bound coenzymes in an RNA world. The idea of coenzyme utilization by ribozymes can be explored by selection-amplification of coenzyme-binding RNAs and coenzyme-assisted ribozymes. Here, we review coenzyme-RNAs, and discuss their possible significance for RNA-mediated metabolism. In summary, a plausible route from prebiotic chemistry to ribozyme biochemistry exists for CoA, and via similar activities, likely exists for all the nucleotidyl coenzymes.

  18. Genetic engineering of Ganoderma lucidum for the efficient production of ganoderic acids

    PubMed Central

    Xu, Jun-Wei; Zhong, Jian-Jiang

    2015-01-01

    Ganoderma lucidum is a well-known traditional medicinal mushroom that produces ganoderic acids with numerous interesting bioactivities. Genetic engineering is an efficient approach to improve ganoderic acid biosynthesis. However, reliable genetic transformation methods and appropriate genetic manipulation strategies remain underdeveloped and thus should be enhanced. We previously established a homologous genetic transformation method for G. lucidum; we also applied the established method to perform the deregulated overexpression of a homologous 3-hydroxy-3-methyl-glutaryl coenzyme A reductase gene in G. lucidum. Engineered strains accumulated more ganoderic acids than wild-type strains. In this report, the genetic transformation systems of G. lucidum are described; current trends are also presented to improve ganoderic acid production through the genetic manipulation of G. lucidum. PMID:26588475

  19. Pleiotropic vasoprotective effects of statins: The chicken or the egg?

    PubMed Central

    Kirmizis, Dimitrios; Chatzidimitriou, Dimitrios

    2009-01-01

    Statins (3-hydroxy-3-methyl glutaryl coenzyme A [HMG-CoA] reductase inhibitors) are the most commonly used lipid-lowering drugs. Their main lipid-lowering effect is achieved by an increase in the expression of low-density lipoprotein cholesterol receptors associated with inhibition of cholesterol synthesis through inhibition of HMG-CoA reductase – the first and rate-limiting step in cholesterol synthesis. However, beyond cholesterol synthesis inhibition, inhibition of the HMG-CoA reductase affects as well the synthesis of other molecules with significant roles in different, yet often intercalating, metabolic pathways. On this basis, and supported by an increasing series of advocating epidemiological and experimental data, an extended dialogue has been established over the last few years regarding the nonlipid or “pleiotropic” actions of statins. PMID:19920934

  20. Regulation of the Lactobacillus Strains on HMGCoA Reductase Gene Transcription in Human HepG2 Cells via Nuclear Factor-κB.

    PubMed

    Chen, Kun; Li, Shaocong; Chen, Fang; Li, Jun; Luo, Xuegang

    2016-02-01

    Lactic acid bacteria have been identified to be effective in reducing cholesterol levels. Most of the mechanistic studies were focused on the bile salt deconjugation ability of bile salt hydrolase in lactic acid bacteria. However, the mechanism by which Lactobacillus decreases cholesterol levels has not been thoroughly studied in intact primate cells. 3-Hydroxy-3- methyl-glutaryl-coenzyme A reductase (HMGCR) is the vital enzyme in cholesterol synthesis. To confirm the effect of probiotic Lactobacillus strains on HMGCR level, in the present study, human hepatoma HepG2 cells were treated with Lactobacillus strains, and then the HMGCR level was illustrated by luciferase reporter assay and RT-PCR. The results showed that the level of HMGCR was suppressed after being treated with the live Lactobacillus strains. These works might set a foundation for the following study of the antihyperlipidemic effects of L. acidophilus, and contribute to the development of functional foods or drugs that benefit patients suffering from hyperlipidemia diseases.

  1. Lovastatin and sodium phenylacetate normalize the levels of very long chain fatty acids in skin fibroblasts of X- adrenoleukodystrophy.

    PubMed

    Singh, I; Pahan, K; Khan, M

    1998-04-24

    The present study underlines the importance of lovastatin, an inhibitor of 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase, and the sodium salt of phenylacetic acid (NaPA), an inhibitor of mevalonate pyrophosphate decarboxylase, in normalizing the pathognomonic accumulation of saturated very long chain fatty acids (VLCFA) in cultured skin fibroblasts of X-adrenoleukodystrophy (X-ALD) in which the ALD gene is either mutated or deleted. Lovastatin or NaPA alone or in combination stimulated the beta-oxidation of lignoceric acid (C24:0) and normalized the elevated levels of VLCFA in skin fibroblasts of X-ALD. Ability of lovastatin and NaPA to normalize the pathognomonic accumulation of VLCFA in skin fibroblasts of X-ALD may identify these drugs as possible therapeutics for X-ALD.

  2. Genetic engineering of Ganoderma lucidum for the efficient production of ganoderic acids.

    PubMed

    Xu, Jun-Wei; Zhong, Jian-Jiang

    2015-01-01

    Ganoderma lucidum is a well-known traditional medicinal mushroom that produces ganoderic acids with numerous interesting bioactivities. Genetic engineering is an efficient approach to improve ganoderic acid biosynthesis. However, reliable genetic transformation methods and appropriate genetic manipulation strategies remain underdeveloped and thus should be enhanced. We previously established a homologous genetic transformation method for G. lucidum; we also applied the established method to perform the deregulated overexpression of a homologous 3-hydroxy-3-methyl-glutaryl coenzyme A reductase gene in G. lucidum. Engineered strains accumulated more ganoderic acids than wild-type strains. In this report, the genetic transformation systems of G. lucidum are described; current trends are also presented to improve ganoderic acid production through the genetic manipulation of G. lucidum.

  3. Palmiwon attenuates hepatic lipid accumulation and hyperlipidemia in a menopausal rat model

    PubMed Central

    Go, Hiroe; Ryuk, Jin Ah; Lee, Hye Won; Ko, Byoung Seob

    2015-01-01

    Abstract Objective We examined the phytoestrogenic effects of palmiwon on breast carcinoma, lipid accumulation in methyl-β-cyclodextrin–induced HepG2 cells, and lipid-related diseases in a rat model of menopausal hyperlipidemia. Methods E-Screen assay was used to screen for phytoestrogens, especially those with antiestrogenic activity, in MCF-7 cells. Oil Red O staining and intracellular cholesterol analyses were used to quantify cellular cholesterol levels. 3-Hydroxy-3-methyl glutaryl coenzyme A reductase assay was used to measure enzyme activity. The levels of phosphorylated adenosine monophosphate–activated protein kinases and products of genes involved in cholesterol synthesis were measured by Western blot analysis. Thirty rats were either ovariectomized or sham-operated and randomly assigned to four groups (n = 5)—Sham, OVX, OVX-SV, or OVX-PMW (50, 150, or 450 mg/kg) group—for 8 weeks. A number of targets associated with lipid-related diseases were examined to confirm the estrogenic effects of palmiwon. Results Palmiwon showed antiestrogenic activity in MCF-7 cells. Palmiwon decreased lipid accumulation, total cholesterol levels, and low-density lipoprotein/very-low-density lipoprotein levels in HepG2 cells. Moreover, palmiwon reversed the effects of methyl-β-cyclodextrin on cholesterol synthesis regulators and inhibited the activity of 3-hydroxy-3-methyl glutaryl coenzyme A reductase. Phosphorylation of adenosine monophosphate–activated protein kinase was stimulated by palmiwon. In ovariectomized rats, palmiwon reduced retroperitoneal and perirenal fat accumulation, serum lipids, atherogenic index, cardiac risk factor score, intima-media thickness, and nonalcoholic steatohepatitis scores. Conclusions These results indicate that palmiwon inhibits lipid accumulation without estrogenic activity in the breast. Therefore, palmiwon may have potential as a therapeutic agent for the treatment of hyperlipidemia in postmenopausal women. PMID:25563794

  4. Hamsters predisposed to sucrose-induced cholesterol gallstones (LPN strain) are more resistant to excess dietary cholesterol than hamsters that are not sensitive to cholelithiasis induction.

    PubMed

    Souidi, M; Combettes-Souverain, M; Milliat, F; Eckhardt, E R; Audas, O; Dubrac, S; Parquet, M; Férézou, J; Lutton, C

    2001-06-01

    We compared the effects of cholesterol feeding in male hamsters from two strains with different propensities to sucrose-induced cholelithiasis; Laboratoire de Physiologie de la Nutrition (LPN) hamsters are predisposed to developing biliary cholesterol gallstones, whereas Janvier (JAN) hamsters are not. When fed a basal control diet, LPN hamsters had a lower cholesterolemia (-21%, P = 0.01) than JAN hamsters, and a higher activity of 3-hydroxy-3-methyl glutaryl coenzyme A reductase in liver (+148%, P = 0.018) and intestine (+281%, P < 0.0001). After feeding the same diet enriched with 0.3% cholesterol for 5 wk, cholesterolemia increased more dramatically in JAN hamsters (+235%, P < 0.001) than in LPN hamsters (+108%, P < 0.001), as did the liver concentration of cholesterol, which reached 152.30 +/- 13.00 and 44.41 +/- 9.06 micromol/g, respectively. Only JAN hamsters displayed hepatomegaly, with an increased cholesterol saturation index of the gallbladder bile (+100%, P < 0.01), due to the cholesterol challenge. In liver, cholesterol feeding reduced cholesterol 7alpha-hydroxylase activity and mRNA level, and stimulated sterol 27-hydroxylase and oxysterol 7alpha-hydroxylase activities. Hepatic levels of LDL receptor decreased by approximately 60% in both strains, whereas HDL receptor scavenger class B type 1 (SR-BI) levels were unaffected by dietary cholesterol. The greater resistance of LPN hamsters to the hypercholesterolemic diet can be explained by a lower capacity to store cholesterol in the liver and greater efficiency in reducing the activity of 3-hydroxy-3-methyl glutaryl coenzyme A reductase in response to cholesterol feeding [from 11263 to 261 pmol/(min x organ) in LPN hamsters and from 4530 to 694 pmol/(min x organ) in JAN hamsters]. These results highlight the usefulness of this two-strain model, which offers some analogy with the inverse association between the predisposition to cholelithiasis and the risk of atherosclerosis in humans.

  5. Lysine glutarylation is a protein posttranslational modification regulated by SIRT5.

    PubMed

    Tan, Minjia; Peng, Chao; Anderson, Kristin A; Chhoy, Peter; Xie, Zhongyu; Dai, Lunzhi; Park, Jeongsoon; Chen, Yue; Huang, He; Zhang, Yi; Ro, Jennifer; Wagner, Gregory R; Green, Michelle F; Madsen, Andreas S; Schmiesing, Jessica; Peterson, Brett S; Xu, Guofeng; Ilkayeva, Olga R; Muehlbauer, Michael J; Braulke, Thomas; Mühlhausen, Chris; Backos, Donald S; Olsen, Christian A; McGuire, Peter J; Pletcher, Scott D; Lombard, David B; Hirschey, Matthew D; Zhao, Yingming

    2014-04-01

    We report the identification and characterization of a five-carbon protein posttranslational modification (PTM) called lysine glutarylation (Kglu). This protein modification was detected by immunoblot and mass spectrometry (MS), and then comprehensively validated by chemical and biochemical methods. We demonstrated that the previously annotated deacetylase, sirtuin 5 (SIRT5), is a lysine deglutarylase. Proteome-wide analysis identified 683 Kglu sites in 191 proteins and showed that Kglu is highly enriched on metabolic enzymes and mitochondrial proteins. We validated carbamoyl phosphate synthase 1 (CPS1), the rate-limiting enzyme in urea cycle, as a glutarylated protein and demonstrated that CPS1 is targeted by SIRT5 for deglutarylation. We further showed that glutarylation suppresses CPS1 enzymatic activity in cell lines, mice, and a model of glutaric acidemia type I disease, the last of which has elevated glutaric acid and glutaryl-CoA. This study expands the landscape of lysine acyl modifications and increases our understanding of the deacylase SIRT5.

  6. Lysine Glutarylation Is a Protein Post-Translational Modification Regulated by SIRT5

    PubMed Central

    Tan, Minjia; Peng, Chao; Anderson, Kristin A.; Chhoy, Peter; Xie, Zhongyu; Dai, Lunzhi; Park, Jeong Soon; Chen, Yue; Huang, He; Zhang, Yi; Ro, Jennifer; Wagner, Gregory R.; Green, Michelle F.; Madsen, Andreas S.; Schmiesing, Jessica; Peterson, Brett S.; Xu, Guofeng; Ilkayeva, Olga R.; Muehlbauer, Michael J.; Braulke, Thomas; Mühlhausen, Chris; Backos, Donald S.; Olsen, Christian A.; McGuire, Peter J.; Pletcher, Scott D.; Lombard, David B.; Hirschey, Matthew D.; Zhao, Yingming

    2014-01-01

    We report the identification and characterization of a five-carbon protein post-translational modification (PTM) called lysine glutarylation (Kglu). This protein modification was detected by immunoblot and mass spectrometry (MS), and then comprehensively validated by chemical and biochemical methods. We demonstrated that the previously annotated deacetylase, sirtuin 5 (SIRT5), is a lysine deglutarylase. Proteome-wide analysis identified 683 Kglu sites in 191 proteins and showed Kglu is highly enriched on metabolic enzymes and mitochondrial proteins. We validated carbamoyl phosphate synthase 1 (CPS1), the rate-limiting enzyme in urea cycle, as a glutarylated protein and demonstrated that CPS1 is targeted by SIRT5 for deglutarylation. We further showed that glutarylation suppresses CPS1 enzymatic activity in cell lines, mice, and a model of glutaric academia type I disease, the last of which has elevated glutaric acid and glutaryl-CoA. This study expands the landscape of lysine acyl modifications and increases our understanding of the deacylase SIRT5. PMID:24703693

  7. Synthesis and GGCT Inhibitory Activity of N-Glutaryl-L-alanine Analogues.

    PubMed

    Ii, Hiromi; Yoshiki, Tatsuhiro; Hoshiya, Naoyuki; Uenishi, Jun'ichi

    2016-01-01

    γ-Glutamylcyclotransferase (GGCT) is an important enzyme that cleaves γ-glutamyl-amino acid in the γ-glutamyl cycle to release 5-oxoproline and amino acid. Eighteen N-acyl-L-alanine analogues including eleven new compounds have been synthesized and examined for their inhibitory activity against recombinant human GGCT protein. Simple N-glutaryl-L-alanine was found to be the most potent inhibitor for GGCT. Other N-glutaryl-L-alanine analogues having methyl and dimethyl substituents at the 2-position were moderately effective, while N-(3R-aminoglutary)-L-alanine, the substrate having an (R)-amino group at the 3-position or N-(N-methyl-3-azaglutaryl)-L-alanine, the substrate having an N-methyl substituent on the 3-azaglutaryl carbon, in constract, exhibited excellent inhibition properties.

  8. Coenzyme Q10 Therapy

    PubMed Central

    Garrido-Maraver, Juan; Cordero, Mario D.; Oropesa-Ávila, Manuel; Fernández Vega, Alejandro; de la Mata, Mario; Delgado Pavón, Ana; de Miguel, Manuel; Pérez Calero, Carmen; Villanueva Paz, Marina; Cotán, David; Sánchez-Alcázar, José A.

    2014-01-01

    For a number of years, coenzyme Q10 (CoQ10) was known for its key role in mitochondrial bioenergetics; later studies demonstrated its presence in other subcellular fractions and in blood plasma, and extensively investigated its antioxidant role. These 2 functions constitute the basis for supporting the clinical use of CoQ10. Also, at the inner mitochondrial membrane level, CoQ10 is recognized as an obligatory cofactor for the function of uncoupling proteins and a modulator of the mitochondrial transition pore. Furthermore, recent data indicate that CoQ10 affects the expression of genes involved in human cell signaling, metabolism and transport, and some of the effects of CoQ10 supplementation may be due to this property. CoQ10 deficiencies are due to autosomal recessive mutations, mitochondrial diseases, aging-related oxidative stress and carcinogenesis processes, and also statin treatment. Many neurodegenerative disorders, diabetes, cancer, and muscular and cardiovascular diseases have been associated with low CoQ10 levels as well as different ataxias and encephalomyopathies. CoQ10 treatment does not cause serious adverse effects in humans and new formulations have been developed that increase CoQ10 absorption and tissue distribution. Oral administration of CoQ10 is a frequent antioxidant strategy in many diseases that may provide a significant symptomatic benefit. PMID:25126052

  9. Probing conformational states of glutaryl-CoA dehydrogenase by fragment screening

    SciTech Connect

    Begley, Darren W.; Davies, Douglas R.; Hartley, Robert C.; Hewitt, Stephen N.; Rychel, Amanda L.; Myler, Peter J.; Van Voorhis, Wesley C.; Staker, Bart L.; Stewart, Lance J.

    2014-10-02

    Glutaric acidemia type 1 is an inherited metabolic disorder which can cause macrocephaly, muscular rigidity, spastic paralysis and other progressive movement disorders in humans. The defects in glutaryl-CoA dehydrogenase (GCDH) associated with this disease are thought to increase holoenzyme instability and reduce cofactor binding. Here, the first structural analysis of a GCDH enzyme in the absence of the cofactor flavin adenine dinucleotide (FAD) is reported. The apo structure of GCDH from Burkholderia pseudomallei reveals a loss of secondary structure and increased disorder in the FAD-binding pocket relative to the ternary complex of the highly homologous human GCDH. After conducting a fragment-based screen, four small molecules were identified which bind to GCDH from B. pseudomallei. Complex structures were determined for these fragments, which cause backbone and side-chain perturbations to key active-site residues. Structural insights from this investigation highlight differences from apo GCDH and the utility of small-molecular fragments as chemical probes for capturing alternative conformational states of preformed protein crystals.

  10. Coenzyme Q and Mitochondrial Disease

    ERIC Educational Resources Information Center

    Quinzii, Catarina M.; Hirano, Michio

    2010-01-01

    Coenzyme Q[subscript 10] (CoQ[subscript 10]) is an essential electron carrier in the mitochondrial respiratory chain and an important antioxidant. Deficiency of CoQ[subscript 10] is a clinically and molecularly heterogeneous syndrome, which, to date, has been found to be autosomal recessive in inheritance and generally responsive to CoQ[subscript…

  11. Betacyanins from vine cactus Hylocereus polyrhizus.

    PubMed

    Wybraniec, S; Platzner, I; Geresh, S; Gottlieb, H E; Haimberg, M; Mogilnitzki, M; Mizrahi, Y

    2001-12-01

    The presence of betacyanin pigments and their isoforms has been detected in the fruit of Hylocereus polyrhizus, a vine cactus native to South America. Along with the known betanin and phyllocactin (6'-O-malonylbetanin), a new betacyanin was structurally elucidated as betanidin 5-O-[6'-O-(3"-hydroxy-3"-methyl-glutaryl)-beta-D-glucopyranoside] (proposed trivial name hylocerenin) by means of electrospray MS/MS, HPLC, and NMR techniques.

  12. Current and Emerging Uses of Statins in Clinical Therapeutics: A Review

    PubMed Central

    Davies, Jonathan T.; Delfino, Spencer F.; Feinberg, Chad E.; Johnson, Meghan F.; Nappi, Veronica L.; Olinger, Joshua T.; Schwab, Anthony P.; Swanson, Hollie I.

    2016-01-01

    Statins, a class of cholesterol-lowering medications that inhibit 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, are commonly administered to treat atherosclerotic cardiovascular disease. Statin use may expand considerably given its potential for treating an array of cholesterol-independent diseases. However, the lack of conclusive evidence supporting these emerging therapeutic uses of statins brings to the fore a number of unanswered questions including uncertainties regarding patient-to-patient variability in response to statins, the most appropriate statin to be used for the desired effect, and the efficacy of statins in treating cholesterol-independent diseases. In this review, the adverse effects, costs, and drug–drug and drug–food interactions associated with statin use are presented. Furthermore, we discuss the pleiotropic effects associated with statins with regard to the onset and progression of autoimmune and inflammatory diseases, cancer, neurodegenerative disorders, strokes, bacterial infections, and human immunodeficiency virus. Understanding these issues will improve the prognosis of patients who are administered statins and potentially expand our ability to treat a wide variety of diseases. PMID:27867302

  13. Statins and angiogenesis: Is it about connections?

    SciTech Connect

    Khaidakov, Magomed; Wang, Wenze; Khan, Junaid A.; Kang, Bum-Yong; Hermonat, Paul L.; Mehta, Jawahar L.

    2009-09-25

    Statins, inhibitors of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, have been shown to induce both angiogenic and angiostatic responses. We attempted to resolve this controversy by studying the effects of two different statins, rosuvastatin and simvastatin, in two different assay systems. In the matrigel angiogenesis assay, both statins enhanced tube formation by human umbilical vein endothelial cells (HUVECs, p < 0.01 vs. control). In the ex vivo mouse aortic ring sprouting assay, both statins virtually abolished new vessel formation (p < 0.01). As a basic difference between the two models of angiogenesis is dispersed state of endothelial cells vs. compact monolayer, we analyzed influence of statins on endothelial junction proteins. RT-PCR analysis and cytoimmunostaining of HUVECs treated with simvastatin revealed increased expression of VE-cadherin (p < 0.05). The blockade of VE-cadherin with a specific antibody reversed simvastatin-induced tube formation (p < 0.002). These data suggest that statins through VE-cadherin stimulation modulate cell-cell adhesion and diminish the ability of cells to proliferate and migrate. The observations of reduced angiogenesis in the intact vessel may relate to anti-atherosclerotic and anti-cancer effects of statins, and provide a feasible explanation for conflicting data under different experimental conditions.

  14. Benefit–risk assessment of HMG-CoA reductase inhibitors (statins): a discrete choice experiment

    PubMed Central

    Sornlertlumvanich, Korn; Ngorsuraches, Surachat

    2016-01-01

    Objectives To conduct the benefit–risk assessment of 3-hydroxy-3-methyl-glutaryl (HMG) coenzyme A reductase inhibitors (statins) using a discrete choice experiment, based on 3 major stakeholders’ perspectives including patients, experts and policymakers in Thailand. Design A discrete choice experiment questionnaire survey in three stakeholders’ perspectives. Setting Public hospitals in Thailand. Participants A total of 353 policymakers, experts and patients. Outcomes Stakeholders’ preferences for assessment criteria (stroke reduction, myocardial infarction reduction, myalgia and hepatotoxicity). Statins’ ranking and maximum acceptable risk in all perspectives were also calculated. Results For any perspective, the most and least important criteria were the risk of hepatotoxicity and the benefit of myocardial infarction reduction, respectively. Patients and experts agreed on the order of importance for myalgia and stroke reduction, but policymakers had different order of importance in these criteria. Overall, results showed that the highest and lowest chances of being chosen were atorvastatin and rosuvastatin, respectively. Only patients’ ranking order was different from others. Maximum acceptable risk of hepatotoxicity was lower than that of myalgia, reflecting the greater concern of all perspectives to statin consequence on liver. Conclusions The results of benefit–risk assessment from every perspective were somewhat consistent. This study demonstrated the feasibility of applying a discrete choice experiment in the benefit–risk assessment of drugs and encouraged the engagement of multiple stakeholders in the decision-making process. PMID:26916689

  15. HMG-CoA reductase inhibitory activity and phytocomponent investigation of Basella alba leaf extract as a treatment for hypercholesterolemia

    PubMed Central

    Baskaran, Gunasekaran; Salvamani, Shamala; Ahmad, Siti Aqlima; Shaharuddin, Noor Azmi; Pattiram, Parveen Devi; Shukor, Mohd Yunus

    2015-01-01

    The enzyme 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase is the key enzyme of the mevalonate pathway that produces cholesterol. Inhibition of HMG-CoA reductase reduces cholesterol biosynthesis in the liver. Synthetic drugs, statins, are commonly used for the treatment of hypercholesterolemia. Due to the side effects of statins, natural HMG-CoA reductase inhibitors of plant origin are needed. In this study, 25 medicinal plant methanol extracts were screened for anti-HMG-CoA reductase activity. Basella alba leaf extract showed the highest inhibitory effect at about 74%. Thus, B. alba was examined in order to investigate its phytochemical components. Gas chromatography with tandem mass spectrometry and reversed phase high-performance liquid chromatography analysis revealed the presence of phenol 2,6-bis(1,1-dimethylethyl), 1-heptatriacotanol, oleic acid, eicosyl ester, naringin, apigenin, luteolin, ascorbic acid, and α-tocopherol, which have been reported to possess antihypercholesterolemic effects. Further investigation of in vivo models should be performed in order to confirm its potential as an alternative treatment for hypercholesterolemia and related cardiovascular diseases. PMID:25609924

  16. Inhibitory Effect on In Vitro LDL Oxidation and HMG Co-A Reductase Activity of the Liquid-Liquid Partitioned Fractions of Hericium erinaceus (Bull.) Persoon (Lion's Mane Mushroom)

    PubMed Central

    Aminudin, Norhaniza

    2014-01-01

    Oxidation of low-density lipoprotein (LDL) has been strongly suggested as the key factor in the pathogenesis of atherosclerosis. Mushrooms have been implicated in having preventive effects against chronic diseases due especially to their antioxidant properties. In this study, in vitro inhibitory effect of Hericium erinaceus on LDL oxidation and the activity of the cholesterol biosynthetic key enzyme, 3-hydroxy-3-methyl glutaryl coenzyme A (HMG Co-A) reductase, was evaluated using five liquid-liquid solvent fractions consisting of methanol : dichloromethane (M : DCM), hexane (HEX), dichloromethane (DCM), ethyl acetate (EA), and aqueous residue (AQ). The hexane fraction showed the highest inhibition of oxidation of human LDL as reflected by the increased lag time (100 mins) for the formation of conjugated diene (CD) at 1 µg/mL and decreased production (68.28%, IC50 0.73 mg/mL) of thiobarbituric acid reactive substances (TBARS) at 1 mg/mL. It also mostly inhibited (59.91%) the activity of the HMG Co-A reductase at 10 mg/mL. The GC-MS profiling of the hexane fraction identified the presence of myconutrients: inter alia, ergosterol and linoleic acid. Thus, hexane fraction of Hericium erinaceus was found to be the most potent in vitro inhibitor of both LDL oxidation and HMG Co-A reductase activity having therapeutic potential for the prevention of oxidative stress-mediated vascular diseases. PMID:24959591

  17. Cholesterol metabolism is altered in Rett syndrome: a study on plasma and primary cultured fibroblasts derived from patients.

    PubMed

    Segatto, Marco; Trapani, Laura; Di Tunno, Ilenia; Sticozzi, Claudia; Valacchi, Giuseppe; Hayek, Joussef; Pallottini, Valentina

    2014-01-01

    Rett (RTT) syndrome is a severe neurological disorder that affects almost exclusively females. Several detectable mutations in the X-linked methyl-CpG-binding protein 2 gene (MECP2) are responsible for the onset of the disease. MeCP2 is a key transcription regulator involved in gene silencing via methylation-dependent remodeling of chromatin. Recent data highlight that lipid metabolism is perturbed in brains and livers of MECP2-null male mice. In addition, altered plasma lipid profile in RTT patients has been observed. Thus, the aim of the work is to investigate the protein network involved in cholesterol homeostasis maintenance on freshly isolated fibroblasts and plasma from both RTT and healthy donors. To this end, protein expression of 3-hydroxy-3methyl glutaryl Coenzyme A reductase (HMGR), sterol regulatory element binding proteins (SREBPs), low density lipoprotein receptor (LDLr) and scavenger receptor B-1 (SRB-1) was assessed in cultured skin fibroblasts from unaffected individuals and RTT patients. In addition, lipid profile and the abundance of proprotein convertase subtilisin/kexin type 9 (PCSK9) were analyzed on plasma samples. The obtained results demonstrate that the main proteins belonging to cholesterol regulatory network are altered in RTT female patients, providing the proof of principle that cholesterol metabolism may be taken into account as a new target for the treatment of specific features of RTT pathology.

  18. Cholesterol Metabolism Is Altered in Rett Syndrome: A Study on Plasma and Primary Cultured Fibroblasts Derived from Patients

    PubMed Central

    Segatto, Marco; Trapani, Laura; Di Tunno, Ilenia; Sticozzi, Claudia; Valacchi, Giuseppe; Hayek, Joussef; Pallottini, Valentina

    2014-01-01

    Rett (RTT) syndrome is a severe neurological disorder that affects almost exclusively females. Several detectable mutations in the X-linked methyl-CpG-binding protein 2 gene (MECP2) are responsible for the onset of the disease. MeCP2 is a key transcription regulator involved in gene silencing via methylation-dependent remodeling of chromatin. Recent data highlight that lipid metabolism is perturbed in brains and livers of MECP2-null male mice. In addition, altered plasma lipid profile in RTT patients has been observed. Thus, the aim of the work is to investigate the protein network involved in cholesterol homeostasis maintenance on freshly isolated fibroblasts and plasma from both RTT and healthy donors. To this end, protein expression of 3-hydroxy-3methyl glutaryl Coenzyme A reductase (HMGR), sterol regulatory element binding proteins (SREBPs), low density lipoprotein receptor (LDLr) and scavenger receptor B-1 (SRB-1) was assessed in cultured skin fibroblasts from unaffected individuals and RTT patients. In addition, lipid profile and the abundance of proprotein convertase subtilisin/kexin type 9 (PCSK9) were analyzed on plasma samples. The obtained results demonstrate that the main proteins belonging to cholesterol regulatory network are altered in RTT female patients, providing the proof of principle that cholesterol metabolism may be taken into account as a new target for the treatment of specific features of RTT pathology. PMID:25118178

  19. Statin Decreases Helicobacter pylori Burden in Macrophages by Promoting Autophagy

    PubMed Central

    Liao, Wei-Chih; Huang, Mei-Zi; Wang, Michelle Lily; Lin, Chun-Jung; Lu, Tzu-Li; Lo, Horng-Ren; Pan, Yi-Jiun; Sun, Yu-Chen; Kao, Min-Chuan; Lim, Hui-Jing; Lai, Chih-Ho

    2017-01-01

    Statins, 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase inhibitors, have been found to provide protective effects against several bacterial infectious diseases. Although the use of statins has been shown to enhance antimicrobial treated Helicobacter pylori eradication and reduce H. pylori-mediated inflammation, the mechanisms underlying these effects remain unclear. In this study, in vitro and ex vivo macrophage models were established to investigate the molecular pathways involved in statin-mediated inhibition of H. pylori-induced inflammation. Our study showed that statin treatment resulted in a dose-dependent decrease in intracellular H. pylori burden in both RAW264.7 macrophage cells and murine peritoneal exudate macrophages (PEMs). Furthermore, statin yielded enhanced early endosome maturation and subsequent activation of the autophagy pathway, which promotes lysosomal fusion resulting in degradation of sequestered bacteria, and in turn attenuates interleukin (IL)-1β production. These results indicate that statin not only reduces cellular cholesterol but also decreases the H. pylori burden in macrophages by promoting autophagy, consequently alleviating H. pylori-induced inflammation. PMID:28144585

  20. Genetic factors affecting statin concentrations and subsequent myopathy: a HuGENet systematic review.

    PubMed

    Canestaro, William J; Austin, Melissa A; Thummel, Kenneth E

    2014-11-01

    Statins, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors, have proven efficacy in both lowering low-density-lipoprotein levels and preventing major coronary events, making them one of the most commonly prescribed drugs in the United States. Statins exhibit a class-wide side effect of muscle toxicity and weakness, which has led regulators to impose both dosage limitations and a recall. This review focuses on the best-characterized genetic factors associated with increased statin muscle concentrations, including the genes encoding cytochrome P450 enzymes (CYP2D6, CYP3A4, and CYP3A5), a mitochondrial enzyme (GATM), an influx transporter (SLCO1B1), and efflux transporters (ABCB1 and ABCG2). A systematic literature review was conducted to identify relevant research evaluating the significance of genetic variants predictive of altered statin concentrations and subsequent statin-related myopathy. Studies eligible for inclusion must have incorporated genotype information and must have associated it with some measure of myopathy, either creatine kinase levels or self-reported muscle aches and pains. After an initial review, focus was placed on seven genes that were adequately characterized to provide a substantive review: CYP2D6, CYP3A4, CYP3A5, GATM, SLCO1B1, ABCB1, and ABCG2. All statins were included in this review. Among the genetic factors evaluated, statin-related myopathy appears to be most strongly associated with variants in SLCO1B1.

  1. Triple-negative breast cancer: is there a treatment on the horizon?

    PubMed Central

    Yao, Hui; He, Guangchun; Yan, Shichao; Chen, Chao; Song, Liujiang; Rosol, Thomas J.; Deng, Xiyun

    2017-01-01

    Triple-negative breast cancer (TNBC), which accounts for 15–20% of all breast cancers, does not express estrogen receptor (ER) or progesterone receptor (PR) and lacks human epidermal growth factor receptor 2 (HER2) overexpression or amplification. These tumors have a more aggressive phenotype and a poorer prognosis due to the high propensity for metastatic progression and absence of specific targeted treatments. Patients with TNBC do not benefit from hormonal or trastuzumab-based targeted therapies because of the loss of target receptors. Although these patients respond to chemotherapeutic agents such as taxanes and anthracyclines better than other subtypes of breast cancer, prognosis remains poor. A group of targeted therapies under investigation showed favorable results in TNBC, especially in cancers with BRCA mutation. The lipid-lowering statins (3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitors), including lovastatin and simvastatin, have been shown to preferentially target TNBC compared with non-TNBC. These statins hold great promise for the management of TNBC. Only with the understanding of the molecular basis for the preference of statins for TNBC and more investigations in clinical trials can they be reformulated into a clinically approved drug against TNBC. PMID:27765921

  2. An examination of the evidence supporting the association of dietary cholesterol and saturated fats with serum cholesterol and development of coronary heart disease.

    PubMed

    Volk, Marion G

    2007-09-01

    The lipid hypothesis is the basis for much of the contemporary diet advice and drug therapy aimed at preventing coronary heart disease (CHD), and was developed from a sequential association of dietary lipids, cholesterol, and CHD nearly 100 years ago. The lipid hypothesis considers pathological changes that relate to the end stage of the complex chronic condition summarized as CHD, not to its genesis. Ongoing research provides only inconclusive evidence of the effects of modification of total, saturated, monounsaturated, or polyunsaturated fats on cardiovascular morbidity and mortality. 3-Hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors or statins, the highest selling drugs in medical history, may provide evidence that the lipid hypothesis is based on erroneous assumptions, since some of the mechanisms of action of statins seem to be independent of cholesterol reduction. This article assesses the methodology and assumptions underlying the early studies that gave rise to the current assumption of a causal relationship between dietary fat consumption and CHD. It argues that flaws in methodology have led to inaccurate and highly debatable conclusions. It assesses research supporting criticism of these early studies and considers other factors that may influence CHD. It offers alternative interpretations of the use of statins in controlling CHD. Finally, it provides an historical context suggesting different causes of CHD that have no relation to fat intake.

  3. Effects of dietary hull-less barley β-glucan on the cholesterol metabolism of hypercholesterolemic hamsters.

    PubMed

    Tong, Li-Tao; Zhong, Kui; Liu, Liya; Zhou, Xianrong; Qiu, Ju; Zhou, Sumei

    2015-02-15

    The aim of the present study is to investigate the hypocholesterolemic effects of dietary hull-less barley β-glucan (HBG) on cholesterol metabolism in hamsters which were fed a hypercholesterolemic diet. The hamsters were divided into 3 groups and fed experimental diets, containing 5‰ HBG or 5‰ oat β-glucan (OG), for 30days. The HBG, as well as OG, lowered the concentration of plasma LDL-cholesterol significantly. The excretion of total lipids and cholesterol in feces were increased in HBG and OG groups compared with the control group. The activity of 3-hydroxy-3-methyl glutaryl-coenzyme A (HMG-CoA) reductase in liver was reduced significantly in the HBG group compared with the control and OG groups. The activity of cholesterol 7-α hydroxylase (CYP7A1) in the liver, in the HBG and OG groups, was significantly increased compared with the control group. The concentrations of acetate, propionate and total short chain fatty acids (SCFAs) were not significantly different between the HBG and control groups. These results indicate that dietary HBG reduces the concentration of plasma LDL cholesterol by promoting the excretion of fecal lipids, and regulating the activities of HMG-CoA reductase and CYP7A1 in hypercholesterolemic hamsters.

  4. Dual effects of statins therapy in systemic lupus erythematosus and SLE-related atherosclerosis: the potential role for regulatory T cells.

    PubMed

    Tu, Haiyan; Li, Qi; Xiang, Shilong; Jiang, Hong; Mao, Youying; Shou, Zhangfei; Chen, Jianghua

    2012-05-01

    Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease associated with accelerated atherosclerosis independent of traditional risk factors. Statins, the 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors, have been widely prescribed for hyperlipidemia, which could slow the atherosclerosis progression, and reduce cardiovascular disease events. Nonetheless, accumulated evidences suggested that statins exert immunomodulatory and anti-inflammatory functions independent of their lipid-lowering effects. By the virtue of pleiotropic immunomodulatory property, statins may be applied for the treatment of both autoimmunity and atherosclerosis in patients with SLE. Interestingly, it has been well documented that regulatory T cells (Tregs) are involved in the pathogenesis of SLE as well as atherosclerosis. Meanwhile, studies have shown that statins could induce augmented number of Tregs with increased functional inhibitory properties. Thus, we hypothesized that the effect of statins ameliorating lupus disease manifestations and lupus-mediated atherogenesis might be mediated, at least partly, via the activation of Tregs. To our knowledge, this is the first hypothesis focused on that Tregs might be involved in the immunomodulatory effect of statins on SLE and SLE-related atherosclerosis.

  5. Clinical evidence of statin therapy in non-dyslipidemic disorders.

    PubMed

    Ferri, Nicola; Corsini, Alberto

    2014-10-01

    The clinical benefits of statins are strongly related to their low density lipoprotein cholesterol (LDL-C) lowering properties. However, considering that the pharmacological target of statins, the 3-hydroxy-3-methyl-3-glutaryl coenzyme A (HMG-CoA) reductase, is one of the upstream enzyme of the mevalonate pathway, its inhibition may determine a substantial impoverishment of additional lipid moieties required for a proper cellular function. From this hypothesis, several experimental and clinical evidences have been reported indicating additional effects of statins beyond the LDL-C lowering, in particular anti-inflammatory and immunomodulatory effects. Thus statin therapy, indicated for hyperlipidemic patients for primary and secondary prevention of coronary heart disease (CHD) has begun to be considered effective in other diseases not necessarily linked to altered lipid profile. In the present review we summarized the current clinical evidence of the efficacy and safety profile of statins in a variety of diseases, such as rheumatoid arthritis, venous thromboembolism, liver diseases, polycystic ovary syndrome, and age-related macular degeneration. As discussed in the review, pending large, well designed, randomized trials, it is reasonable to conclude that there is no definitive evidence for the use of statins in the aforementioned diseases.

  6. Greater efficacy of atorvastatin versus a non-statin lipid-lowering agent against renal injury: potential role as a histone deacetylase inhibitor

    PubMed Central

    Singh, Ravi Shankar; Chaudhary, Dharmendra Kumar; Mohan, Aradhana; Kumar, Praveen; Chaturvedi, Chandra Prakash; Ecelbarger, Carolyn M.; Godbole, Madan M.; Tiwari, Swasti

    2016-01-01

    Statins, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors have been shown to improve diabetic nephropathy. However, whether they provide protection via Histone deacetylases (HDAC) inhibition is not clear. We conducted a comparative evaluation of Atorvastatin (AT) versus the non-statin cholesterol-lowering drug, Ezetimibe (EZT) on severity of diabetic nephropathy. Streptozotocin-treated male Wistar rats were fed a cholesterol-supplemented diet and gavaged daily with vehicle, AT or EZT. Control rats received normal diet and gavaged vehicle (n = 8–9/group). Diabetes increased blood glucose, urine albumin-to-creatinine ratio (ACR), kidney pathology and HDAC activity, and reduced renal E-cadherin levels. Both AT and EZT reduced circulating cholesterol, attenuated renal pathology, and did not lower blood glucose. However, AT was significantly more effective than EZT at reducing kidney pathology and HDAC activity. Chromatin immunoprecipitation revealed a significantly higher association of acetylated H3 and H4 with the E-cadherin promoter in kidneys from AT-, relative to EZT- or vehicle-treated rats. Moreover, we demonstrated a direct effect of AT, but not EZT, on HDAC-inhibition and, H3 and H4- acetylation in primary glomerular mesangial cells. Overall, both AT and EZT attenuated diabetic nephropathy; however, AT exhibited greater efficacy despite a similar reduction in circulating cholesterol. HDAC-inhibition may underlie greater efficacy of statins in attenuating kidney injury. PMID:27901066

  7. Lovastatin inhibits the extracellular-signal-regulated kinase pathway in immortalized rat brain neuroblasts

    PubMed Central

    Cerezo-Guisado, Maria Isabel; GarcíA-Román, Natalia; García-MaríN, Luis Jesús; Álvarez-Barrientos, Alberto; Bragado, Maria Julia; Lorenzo, Maria Jesús

    2006-01-01

    We have shown previously that lovastatin, a 3-hydroxy-3-methyl- glutaryl coenzyme A reductase inhibitor, induces apoptosis in spontaneously immortalized rat brain neuroblasts. In the present study, we analysed the intracellular signal transduction pathways by which lovastatin induces neuroblast apoptosis. We showed that lovastatin efficiently inhibited Ras activation, which was associ-ated with a significant decrease in ERK1/2 (extracellular-signal-regulated kinase 1/2) phosphorylation. Lovastatin also decreased CREB phosphorylation and CREB-mediated gene expression. The effects of lovastatin on the Ras/ERK1/2/CREB pathway were time- and concentration-dependent and fully prevented by meva-lonate. In addition, we showed that two MEK [MAPK (mitogen-activated protein kinase)/ERK kinase] inhibitors, PD98059 and PD184352, were poor inducers of apoptosis in serum-treated neuroblasts. However, these inhibitors significantly increased apop-tosis induced by lovastatin treatment. Furthermore, we showed that pharmacological inhibition of both MEK and phosphoinos-itide 3-kinase activities was able to induce neuroblast apoptosis with similar efficacy as lovastatin. Our results suggest that lovast-atin triggers neuroblast apoptosis by regulating several signalling pathways, including the Ras/ERK1/2 pathway. These findings might also contribute to elucidate the intracellular mechanisms involved in the central nervous system side effects associated with statin therapy. PMID:16952276

  8. L-Carnitine intake prevents irregular feeding-induced obesity and lipid metabolism disorder.

    PubMed

    Wu, Tao; Guo, Anqi; Shu, Qingyu; Qi, Yangjian; Kong, Ying; Sun, Zhiping; Sun, Shumin; Fu, Zhengwei

    2015-01-10

    L-Carnitine supplementation has been used to reduce obesity caused by high-fat diet, which is beneficial for lowering blood and hepatic lipid levels, and for ameliorating fatty liver. However, whether l-carnitine may affect irregular feeding-induced obesity and lipid metabolism disorder is still largely unknown. In the present study, we developed a time-delayed pattern of eating, and investigated the effects of l-carnitine on the irregular eating induced adiposity in mice. After an experimental period of 8 weeks with l-carnitine supplementation, l-carnitine significantly inhibited body weight increase and epididymal fat weight gain induced by the time-delayed feeding. In addition, l-carnitine administration decreased levels of serum alanine aminotransferase (GPT), glutamic oxalacetic transaminase (GOT) and triglyceride (TG), which were significantly elevated by the irregular feeding. Moreover, mice supplemented with l-carnitine did not display glucose intolerance-associated hallmarks, which were found in the irregular feeding-induced obesity. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that l-carnitine counteracted the negative alterations of lipid metabolic gene expression (fatty acid synthase, 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, cholesterol 7α-hydroxylase, carnitine/acylcarnitine translocase) in the liver and fat of mice caused by the irregular feeding. Therefore, our results suggest that the time-delayed pattern of eating can induce adiposity and lipid metabolic disorders, while l-carnitine supplementation might prevent these negative symptoms.

  9. Rapamycin down-regulates LDL-receptor expression independently of SREBP-2

    SciTech Connect

    Sharpe, Laura J.; Brown, Andrew J.

    2008-09-05

    As a key regulator of cholesterol homeostasis, sterol-regulatory element binding protein-2 (SREBP-2) up-regulates expression of genes involved in cholesterol synthesis (e.g., 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) Reductase) and uptake (the low density lipoprotein (LDL)-receptor). Previously, we showed that Akt, a critical kinase in cell growth and proliferation, contributes to SREBP-2 activation. However, the specific Akt target involved is unknown. A potential candidate is the mammalian target of rapamycin, mTOR. Rapamycin can cause hyperlipidaemia clinically, and we hypothesised that this may be mediated via an effect of mTOR on SREBP-2. Herein, we found that SREBP-2 activation and HMG-CoA Reductase gene expression were unaffected by rapamycin treatment. However, LDL-receptor gene expression was decreased by rapamycin, suggesting that this may contribute to the hyperlipidaemia observed in rapamycin-treated patients. Rapamycin did not affect mRNA stability, so the decrease in LDL-receptor gene expression is likely to be occurring at the transcriptional level, although independently of SREBP-2.

  10. Preventive effects of p-coumaric acid on cardiac hypertrophy and alterations in electrocardiogram, lipids, and lipoproteins in experimentally induced myocardial infarcted rats.

    PubMed

    Roy, Abhro Jyoti; Stanely Mainzen Prince, P

    2013-10-01

    The present study evaluated the preventive effects of p-coumaric acid on cardiac hypertrophy and alterations in electrocardiogram, lipids, and lipoproteins in experimentally induced myocardial infarcted rats. Rats were pretreated with p-coumaric acid (8 mg/kg body weight) daily for a period of 7 days and then injected with isoproterenol (100mg/kg body weight) on 8th and 9th day to induce myocardial infarction. Myocardial infarction induced by isoproterenol was indicated by increased level of cardiac sensitive marker and elevated ST-segments in the electrocardiogram. Also, the levels/concentrations of serum and heart cholesterol, triglycerides and free fatty acids were increased in myocardial infarcted rats. Isoproterenol also increased the levels of serum low density and very low density lipoprotein cholesterol and decreased the levels of high density lipoprotein cholesterol. It also enhanced the activity of liver 3-hydroxy-3 methyl glutaryl-Coenzyme-A reductase. p-Coumaric acid pretreatment revealed preventive effects on all the biochemical parameters and electrocardiogram studied in myocardial infarcted rats. The in vitro study confirmed the free radical scavenging property of p-coumaric acid. Thus, p-coumaric acid prevented cardiac hypertrophy and alterations in lipids, lipoproteins, and electrocardiogram, by virtue of its antihypertrophic, antilipidemic, and free radical scavenging effects in isoproterenol induced myocardial infarcted rats.

  11. COENZYME Q 10 : A REVIEW

    PubMed Central

    Singh, Deependra; Jain, Vandana; Saraf, Swarnlata; Saraf, S

    2002-01-01

    Ubiquinone or Co Q10 is essentially a vitamin like substance and is a cofactor of an enzyme. It is an integral part of the memberanes of mitocondria where it is involved in the energy production. It is a nutrient necessary for the function of every cell of the body especially vital organs of the body like heart, liver, brain etc. Studies have shown that coenzyme Q10 alters the natural history of cardiovascular illness and has the potential of prevention of cardiovascular diseases through the inhibition of LDL cholesterol oxidation by maintenance of optimal cellular and mitochondrial function throughout the ravages of time internal and external stress. PMID:22557086

  12. Purification and immobilization of recombinant variants of Brevundimonas diminuta glutaryl-7-aminocephalosporanic acid acylase expressed in Escherichia coli cells.

    PubMed

    Khatuntseva, S A; Eldarov, M A; Redo, V A; Skryabin, K G

    2008-01-01

    Modified chitin-binding domain (ChBD) from Bacillus circulans chitinase A1 with W42F mutation in chitin-binding site was genetically fused to different positions within alpha-subunit of glutaryl-7-aminocephalosporanic acid acylase (GLA) gene. Hybrid proteins were efficiently expressed in E. coli cells as soluble, enzymatically active and correctly processed holoenzymes. ChBD-GLA fusions were easily affinity purified on chitin column by changing the salt concentration of binding and elution buffer. The developed one-step affinity purification procedure is thus a promising approach for scaled-up isolation of GLA variants for preparation of industrial biocatalysts as well as for structure-functional studies.

  13. Self-Incorporation of Coenzymes by Ribozymes

    NASA Technical Reports Server (NTRS)

    Breaker, Ronald R.; Joyce, Gerald F.

    1995-01-01

    RNA molecules that are assembled from the four standard nucleotides contain a limited number of chemical functional groups, a characteristic that is generally thought to restrict the potential for catalysis by ribozymes. Although polypeptides carry a wider range of functional groups, many contemporary protein-based enzymes employ coenzymes to augment their capabilities. The coenzymes possess additional chemical moieties that can participate directly in catalysis and thereby enhance catalytic function. In this work, we demonstrate a mechanism by which ribozymes can supplement their limited repertoire of functional groups through RNAcatalyzed incorporation of various coenzymes and coenzyme analogues. The group I ribozyme of Tetrahymena thermophila normally mediates a phosphoester transfer reaction that results in the covalent attachment of guanosine to the ribozyme. Here, a shortened version of the ribozyme is shown to catalyze the self-incorporation of coenzymes and coenzyme analogues, such as NAD+ and dephosphorylated CoA-SH. Similar ribozyme activities may have played an important role in the "RNA world," when RNA enzymes are thought to have maintained a complex metabolism in the absence of proteins and would have benefited from the inclusion of additional functional groups.

  14. Epigallocatechin-3-gallate potently inhibits the in vitro activity of hydroxy-3-methyl-glutaryl-CoA reductase[S

    PubMed Central

    Cuccioloni, Massimiliano; Mozzicafreddo, Matteo; Spina, Michele; Tran, Chi Nhan; Falconi, Maurizio; Eleuteri, Anna Maria; Angeletti, Mauro

    2011-01-01

    Hydroxy-3-methyl-glutaryl-CoA reductase (HMGR) is the rate-controlling enzyme of cholesterol synthesis, and owing to its biological and pharmacological relevance, researchers have investigated several compounds capable of modulating its activity with the hope of developing new hypocholesterolemic drugs. In particular, polyphenol-rich extracts were extensively tested for their cholesterol-lowering effect as alternatives, or adjuvants, to the conventional statin therapies, but a full understanding of the mechanism of their action has yet to be reached. Our work reports on a detailed kinetic and equilibrium study on the modulation of HMGR by the most-abundant catechin in green tea, epigallocatechin-3-gallate (EGCG). Using a concerted approach involving spectrophotometric, optical biosensor, and chromatographic analyses, molecular docking, and site-directed mutagenesis on the cofactor site of HMGR, we have demonstrated that EGCG potently inhibits the in vitro activity of HMGR (Ki in the nanomolar range) by competitively binding to the cofactor site of the reductase. Finally, we evaluated the effect of combined EGCG-statin administration. PMID:21357570

  15. A Korean patient with glutaric aciduria type 1 with a novel mutation in the glutaryl CoA dehydrogenase gene.

    PubMed

    Kim, Hee Su; Yu, Hee Joon; Lee, Jeehun; Park, Hyung-Doo; Kim, Ji Hye; Shin, Hyung-Jin; Jin, Dong Kyu; Lee, Munhyang

    2014-01-01

    Mutations in the glutaryl-CoA dehydrogenase gene can result in Glutaric aciduria type 1(GA 1) by accumulation of glutaric acid, 3-hydroxyglutaric acid (3-OH-GA), and glutarylcarnitine (C5DC). GA 1 is characterized by macrocephaly, subdural hemorrhage (SDH), and dystonic movement disorder after acute encephalopathic crisis. We report a Korean patient with GA1 and a novel mutation. A 16-month-old boy presented with SDH, macrocephaly, and developmental delay. In the neurologic examination, the patient had mild axial hypotonia, but otherwise normal neurologic functions. The brain MRI showed large amounts of bilateral SDH and high signal intensity in both basal ganglia and thalamus. Metabolic screening tests detected highly elevated urinary GA levels but 3-OH-glutaric acid was normal. C5DC was 0.94 μM/L (reference range < 0.3 μM/L). The patient had compound heterozygous mutations of the GCDH gene: p.Arg257Gln (c.770G>A) and p.Cys308Arg (c.922T>C). p.Cys308Arg is a novel mutation; reports of p.Arg257Gln were also rare both in Caucasians and Asian populations. In summary, we hereby report one Korean patient with GA1 with clinical, biochemical, and radiologic characteristics confirmed by genetic analysis.

  16. [Enzymatic conversion of cephalosporin C to glutaryl-7-aminocephalosporanic acid using whole cells of the yeast Trigonopsis variabilis FA10].

    PubMed

    Chen, J; Zhu, T B; Zhang, Y F; Yang, Y L; Jiao, R S

    2001-03-01

    A process for the production of glutaryl-7-aminocephalosporanic acid (GL-7ACA) from cephalosporin C(CPC) using permeabilized cells of yeast Trigonopsis variabilis FA10 containing D-amino acid oxidase (DAO) is described. It was found that the bioconversion of CPC to GL-7ACA was interfered by the catalase activity presented in the cells that hydrolyzed the hydrogen peroxide and resulted in the accumulation of alpha-keto-adipyl-7-ACA (AKA-7ACA) and decrease of GL-7ACA yield. the methods to overcome this problem including the addition of extra H2O2 and use of catalase inhibitor, NaN3, were developed and the rate of GL-7ACA from CPC were 73% and 70.1%, respectively. Another alternative method was to incubate the permeabilized FA10 cells at pH10.5-11.0 for 30 minutes at 20 degrees C which served to selectively inactivate the catalase. In the bioconversion of CPC to GL-7ACA using pH10.5-treated cells without catalase activity, the high reaction yield of GL-7ACA(84%) was achieved.

  17. Effective peritoneal therapy of acute pancreatitis in the rat with glutaryl-trialanin-ethylamide: a novel inhibitor of pancreatic elastase.

    PubMed Central

    Fric, P; Slabý, J; Kasafírek, E; Kocna, P; Marek, J

    1992-01-01

    The six hour peritoneal lavage with glutaryl-trialanin-ethylamide, a low molecular competitive inhibitor of pancreatic elastase (IC50-8 mumol/l), effectively suppresses the evolution of taurocholate induced acute pancreatitis in the rat. The lavage alone is followed by a marked decrease of fat necrosis and amylase and lipase activity in serum. The area of pancreatic haemorrhage was significantly reduced only after the lavage solution was supplemented with Glt-Ala3-NHEt. The effect was not enhanced by a bolus injection of the inhibitor before starting the lavage. The combination of Glt-Ala3-NHEt with aprotinin or nafamstate mesilate produced only marginal greater benefit. The effect of Glt-Ala3-NHEt on pancreatic haemorrhage is time and dose related even with delayed onset of the lavage. Animals treated with peritoneal lavage without Get-Ala3-NHEt lived longer than controls (p less than 0.05), but by 60 hours the survival rate of both groups was almost the same (76 v 74%). All animals lavaged with Glt-Ala3-NHEt survived 120 hours and the difference in the survival rate between this and both remaining groups was significant (100% v 76% v 74% - p less than 0.05). The results were considered favourable and preliminary clinical trials of Glt-Ala3-NHEt in subjects with acute pancreatitis justified. PMID:1377154

  18. Coenzyme Q10: Can It Prevent Statin Side Effects?

    MedlinePlus

    ... Q10: Can it prevent statin side effects? Can coenzyme Q10 reduce the risk of side effects from ... Francisco Lopez-Jimenez, M.D. At this time, coenzyme Q10 isn't universally recommended for preventing side ...

  19. Coenzymes, viruses and the RNA world.

    PubMed

    Reyes-Prieto, Fabián; Hernández-Morales, Ricardo; Jácome, Rodrigo; Becerra, Arturo; Lazcano, Antonio

    2012-07-01

    The results of a detailed bioinformatic search for ribonucleotidyl coenzyme biosynthetic sequences in DNA- and RNA viral genomes are presented. No RNA viral genome sequence available as of April 2011 appears to encode for sequences involved in coenzyme biosynthesis. In both single- and double-stranded DNA viruses a diverse array of coenzyme biosynthetic genes has been identified, but none of the viral genomes examined here encodes for a complete pathway. Although our conclusions may be constrained by the unexplored diversity of viral genomes and the biases in the construction of viral genome databases, our results do not support the possibility that RNA viruses are direct holdovers from an ancient RNA/protein world. Extrapolation of our results to evolutionary epochs prior to the emergence of DNA genomes suggest that during those early stages living entities may have depended on discontinuous genetic systems consisting of multiple small-size RNA sequences.

  20. COH-SR4 Reduces Body Weight, Improves Glycemic Control and Prevents Hepatic Steatosis in High Fat Diet-Induced Obese Mice

    PubMed Central

    Figarola, James Lester; Singhal, Preeti; Rahbar, Samuel; Gugiu, Bogdan Gabriel; Awasthi, Sanjay; Singhal, Sharad S.

    2013-01-01

    Obesity is a chronic metabolic disorder caused by imbalance between energy intake and expenditure, and is one of the principal causative factors in the development of metabolic syndrome, diabetes and cancer. COH-SR4 (“SR4”) is a novel investigational compound that has anti-cancer and anti-adipogenic properties. In this study, the effects of SR4 on metabolic alterations in high fat diet (HFD)-induced obese C57BL/J6 mice were investigated. Oral feeding of SR4 (5 mg/kg body weight.) in HFD mice for 6 weeks significantly reduced body weight, prevented hyperlipidemia and improved glycemic control without affecting food intake. These changes were associated with marked decreases in epididymal fat mass, adipocyte hypertrophy, increased plasma adiponectin and reduced leptin levels. SR4 treatment also decreased liver triglycerides, prevented hepatic steatosis, and normalized liver enzymes. Western blots demonstrated increased AMPK activation in liver and adipose tissues of SR4-treated HFD obese mice, while gene analyses by real time PCR showed COH-SR4 significantly suppressed the mRNA expression of lipogenic genes such as sterol regulatory element binding protein-1c (Srebf1), acetyl-Coenzyme A carboxylase (Acaca), peroxisome proliferator-activated receptor gamma (Pparg), fatty acid synthase (Fasn), stearoyl-Coenzyme A desaturase 1 (Scd1), carnitine palmitoyltransferase 1a (Cpt1a) and 3-hydroxy-3-methyl-glutaryl-CoA reductase (Hmgcr), as well as gluconeogenic genes phosphoenolpyruvate carboxykinase 1 (Pck1) and glucose-6-phosphatase (G6pc) in the liver of obese mice. In vitro, SR4 activates AMPK independent of upstream kinases liver kinase B1 (LKB1) and Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ). Together, these data suggest that SR4, a novel AMPK activator, may be a promising therapeutic compound for treatment of obesity, fatty liver disease, and related metabolic disorders. PMID:24376752

  1. Gene encoding acetyl-coenzyme A carboxylase

    DOEpatents

    Roessler, P.G.; Ohlrogge, J.B.

    1996-09-24

    A DNA encoding an acetyl-coenzyme A carboxylase (ACCase) from a photosynthetic organism and functional derivatives are disclosed which are resistant to inhibition from certain herbicides. This gene can be placed in organisms to increase their fatty acid content or to render them resistant to certain herbicides. 5 figs.

  2. Gene encoding acetyl-coenzyme A carboxylase

    DOEpatents

    Roessler, Paul G.; Ohlrogge, John B.

    1996-01-01

    A DNA encoding an acetyl-coenzyme A carboxylase (ACCase) from a photosynthetic organism and functional derivatives thereof which are resistant to inhibition from certain herbicides. This gene can be placed in organisms to increase their fatty acid content or to render them resistant to certain herbicides.

  3. Effects of inhibitors of hydroxymethylglutaryl coenzyme A reductase on coenzyme Q and dolichol biosynthesis.

    PubMed

    Appelkvist, E L; Edlund, C; Löw, P; Schedin, S; Kalén, A; Dallner, G

    1993-01-01

    Inhibitors of hydroxymethylglutaryl coenzyme A reductase are used clinically to decrease blood levels of low-density lipoprotein cholesterol in hypercholesterolemic patients. However, little is known about the possible effects of these inhibitors on dolichol and cholesterol synthesis. Oral administration of mevinolin to rats was found here to decrease dolichol, dolichyl-P and coenzyme Q levels in the heart and skeletal muscle and to increase the hepatic dolichol level while decreasing the coenzyme Q content in this same organ. The amounts of dolichyl-P decreased in heart and muscle and increased in brain. Intraperitoneal administration also affected the levels of these lipids. The concentrations of blood lipids were not modified in the same manner as tissue lipids. Analysis of individual enzyme activities and of incorporation of [3H]acetate into various lipids of liver and brain slices demonstrated that both up- and down-regulation of different proteins occur in various tissues, resulting in modifications in lipid synthesis. Hypercholesterolemic patients were found to have high blood coenzyme Q levels, which are decreased upon pravastatin treatment, although they are still above control values. It appears that these HMG-coenzyme A reductase inhibitors do not selectively lower cholesterol levels, but that they also modify the dolichol and coenzyme Q content and synthesis both in the liver and various other tissues.

  4. Requirement for Coenzyme Q in Plasma Membrane Electron Transport

    NASA Astrophysics Data System (ADS)

    Sun, I. L.; Sun, E. E.; Crane, F. L.; Morre, D. J.; Lindgren, A.; Low, H.

    1992-12-01

    Coenzyme Q is required in the electron transport system of rat hepatocyte and human erythrocyte plasma membranes. Extraction of coenzyme Q from the membrane decreases NADH dehydrogenase and NADH:oxygen oxidoreductase activity. Addition of coenzyme Q to the extracted membrane restores the activity. Partial restoration of activity is also found with α-tocopherylquinone, but not with vitamin K_1. Analogs of coenzyme Q inhibit NADH dehydrogenase and oxidase activity and the inhibition is reversed by added coenzyme Q. Ferricyanide reduction by transmembrane electron transport from HeLa cells is inhibited by coenzyme Q analogs and restored with added coenzyme Q10. Reduction of external ferricyanide and diferric transferrin by HeLa cells is accompanied by proton release from the cells. Inhibition of the reduction by coenzyme Q analogs also inhibits the proton release, and coenzyme Q10 restores the proton release activity. Trans-plasma membrane electron transport stimulates growth of serum-deficient cells, and added coenzyme Q10 increases growth of HeLa (human adenocarcinoma) and BALB/3T3 (mouse fibroblast) cells. The evidence is consistent with a function for coenzyme Q in a trans-plasma membrane electron transport system which influences cell growth.

  5. Coenzyme Q10 and statin-related myopathy.

    PubMed

    2015-05-01

    Statins inhibit the enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, which is involved in the production of mevalonic acid in the cholesterol biosynthesis pathway. This pathway also results in the production of other bioactive molecules including coenzyme Q10 (also known as ubiquinone or ubidecarenone). Coenzyme Q10 is a naturally-occurring coenzyme with antioxidant effects that is involved in electron transport in mitochondria and is thought to play a role in energy transfer in skeletal muscle. Muscle-related problems are a frequently reported adverse effect of statins, and it has been hypothesised that a reduced endogenous coenzyme Q10 concentration is a cause of statin-induced myopathy. Coenzyme Q10 supplementation has therefore been proposed to reduce the adverse muscular effects sometimes seen with statins. Here, we consider whether coenzyme Q10 has a place in the management of statin-induced myopathy.

  6. Better than Nature: Nicotinamide Biomimetics That Outperform Natural Coenzymes.

    PubMed

    Knaus, Tanja; Paul, Caroline E; Levy, Colin W; de Vries, Simon; Mutti, Francesco G; Hollmann, Frank; Scrutton, Nigel S

    2016-01-27

    The search for affordable, green biocatalytic processes is a challenge for chemicals manufacture. Redox biotransformations are potentially attractive, but they rely on unstable and expensive nicotinamide coenzymes that have prevented their widespread exploitation. Stoichiometric use of natural coenzymes is not viable economically, and the instability of these molecules hinders catalytic processes that employ coenzyme recycling. Here, we investigate the efficiency of man-made synthetic biomimetics of the natural coenzymes NAD(P)H in redox biocatalysis. Extensive studies with a range of oxidoreductases belonging to the "ene" reductase family show that these biomimetics are excellent analogues of the natural coenzymes, revealed also in crystal structures of the ene reductase XenA with selected biomimetics. In selected cases, these biomimetics outperform the natural coenzymes. "Better-than-Nature" biomimetics should find widespread application in fine and specialty chemicals production by harnessing the power of high stereo-, regio-, and chemoselective redox biocatalysts and enabling reactions under mild conditions at low cost.

  7. Prebiotic syntheses of vitamin coenzymes: I. Cysteamine and 2-mercaptoethanesulfonic acid (coenzyme M)

    NASA Technical Reports Server (NTRS)

    Miller, S. L.; Schlesinger, G.

    1993-01-01

    The reaction of NH3 and SO3(2-) with ethylene sulfide is shown to be a prebiotic synthesis of cysteamine and 2-mercaptoethanesulfonic acid (coenzyme M). A similar reaction with ethylene imine would give cysteamine and taurine. Ethylene oxide would react with NH3 and N(CH3)3 to give the phospholipid components ethanolamine and choline. The prebiotic sources of ethylene sulfide, ethylene imine and ethylene oxide are discussed. Cysteamine itself is not a suitable thioester for metabolic processes because of acyl transfer to the amino group, but this can be prevented by using an amide of cysteamine. The use of cysteamine in coenzyme A may have been due to its prebiotic abundance. The facile prebiotic synthesis of both cysteamine and coenzyme M suggests that they were involved in very early metabolic pathways.

  8. The production of coenzyme Q10 in microorganisms.

    PubMed

    Cluis, Corinne P; Pinel, Dominic; Martin, Vincent J

    2012-01-01

    Coenzyme Q10 has emerged as a valuable molecule for pharmaceutical and cosmetic applications. Therefore, research into producing and optimizing coenzyme Q10 via microbial fermentation is ongoing. There are two major paths being explored for maximizing production of this molecule to commercially advantageous levels. The first entails using microbes that naturally produce coenzyme Q10 as fermentation biocatalysts and optimizing the fermentation parameters in order to reach industrial levels of production. However, the natural coenzyme Q10-producing microbes tend to be intractable for industrial fermentation settings. The second path to coenzyme Q10 production being explored is to engineer Escherichia coli with the ability to biosynthesize this molecule in order to take advantage of its more favourable fermentation characteristics and the well-understood array of genetic tools available for this bacteria. Although many studies have attempted to over-produce coenzyme Q10 in E. coli through genetic engineering, production titres still remain below those of the natural coenzyme Q10-producing microorganisms. Current research is providing the knowledge needed to alleviate the bottlenecks involved in producing coenzyme Q10 from an E. coli strain platform and the fermentation parameters that could dramatically increase production titres from natural microbial producers. Synthesizing the lessons learned from both approaches may be the key towards a more cost-effective coenzyme Q10 industry.

  9. Effects of HMG-CoA reductase inhibitors on excitation-contraction coupling of rat skeletal muscle.

    PubMed

    Pierno, S; De Luca, A; Liantonio, A; Camerino, C; Conte Camerino, D

    1999-01-01

    3-Hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors currently used as cholesterol-lowering drugs produce side effects in patients, one of which is myopathy. In the present study we compared the effect of a 3-month chronic treatment with two different compounds, simvastatin and pravastatin, on the excitation-contraction coupling of rat skeletal muscle fibers, the mechanism which links membrane depolarization to the movements of cytosolic Ca2+ from intracellular stores. The voltage threshold for mechanical activation of extensor digitorum longus muscle fibers in response to depolarizing pulses of various durations was studied in vitro by the two intracellular microelectrode method in 'point' voltage clamp mode. Simvastatin (5-50 mg/kg) modified the mechanical threshold of striated fibers in a dose-dependent manner. The muscle fibers of rats treated with 10 mg/kg and 50 mg/kg of simvastatin needed significantly less depolarization to contract than did untreated fibers at each pulse duration, suggesting that levels of cytosolic Ca2+ were higher. Consequently, the rheobase voltage for fiber contraction was significantly shifted toward more negative potentials with respect to controls by 2.4 mV and 7.1 mV in the 10 mg/kg and 50 mg/kg simvastatin-treated animals, respectively. Pravastatin treatment at 100 mg/kg did not produce any alteration of excitation-contraction coupling since the rheobase voltage was similar to that of controls. The different physicochemical properties of the two drugs may underlie the different effect observed because lipophilic agents, such as simvastatin, have been shown to affect sterol biosynthesis in many tissues, whereas the hydrophilic pravastatin is hepato-selective.

  10. Ursodeoxycholic acid improves insulin sensitivity and hepatic steatosis by inducing the excretion of hepatic lipids in high-fat diet-fed KK-Ay mice.

    PubMed

    Tsuchida, Takuma; Shiraishi, Muneshige; Ohta, Tetsuya; Sakai, Kaoru; Ishii, Shinichi

    2012-07-01

    Type 2 diabetes mellitus is frequently accompanied by fatty liver/nonalcoholic fatty liver disease. Hence, accumulation of lipids in the liver is considered to be one of the risk factors for insulin resistance and metabolic syndrome. Ursodeoxycholic acid (UDCA) is widely used for the treatment of liver dysfunction. We investigated the therapeutic effects of UDCA on type 2 diabetes mellitus exacerbating hepatic steatosis and the underlying mechanisms of its action using KK-A(y) mice fed a high-fat diet. KK-A(y) mice were prefed a high-fat diet; and 50, 150, and 450 mg/kg of UDCA was orally administered for 2 or 3 weeks. Administration of UDCA decreased fasting hyperglycemia and hyperinsulinemia. Hyperinsulinemic-euglycemic clamp analyses showed that UDCA improved hepatic (but not peripheral) insulin resistance. Hepatic triglyceride and cholesterol contents were significantly reduced by treatment with UDCA, although the genes involved in the synthesis of fatty acids and cholesterol, including fatty acid synthase and 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, were upregulated. Fecal levels of bile acids, neutral sterols, fatty acids, and phospholipids were significantly increased by UDCA treatment. The gene expression levels and protein phosphorylation levels of endoplasmic reticulum stress markers were not changed by UDCA treatment. These results indicate that UDCA ameliorates hyperglycemia and hyperinsulinemia by improving hepatic insulin resistance and steatosis in high-fat diet-fed KK-A(y) mice. Reduction of hepatic lipids might be due to their excretion in feces, followed by enhanced utilization of glucose for the synthesis of fatty acids and cholesterol. Ursodeoxycholic acid should be effective for the treatment of type 2 diabetes mellitus accompanying hepatic steatosis.

  11. Statins alleviate experimental nerve injury-induced neuropathic pain.

    PubMed

    Shi, Xiang Qun; Lim, Tony K Y; Lee, Seunghwan; Zhao, Yuan Qing; Zhang, Ji

    2011-05-01

    The statins are a well-established class of drugs that lower plasma cholesterol levels by inhibiting HMG-CoA (3-hydroxy-3-methyl-glutaryl-coenzyme A) reductase. They are widely used for the treatment of hypercholesterolemia and for the prevention of coronary heart disease. Recent studies suggest that statins have anti-inflammatory effects beyond their lipid-lowering properties. We sought to investigate whether statins could affect neuropathic pain by mediating nerve injury-associated inflammatory responses. The effects of hydrophilic rosuvastatin and lipophilic simvastatin were examined in the mouse partial sciatic nerve ligation model. Systemic daily administration of either statin from days 0 to 14 completely prevented the development of mechanical allodynia and thermal hyperalgesia. When administered from days 8 to 14 after injury, both statins dose-dependently reduced established hypersensitivity. After treatment, the effects of the statins were washed out within 2 to 7 days, depending on dose. Effects of both statins in alleviating mechanical allodynia were further confirmed in a different injury-associated neuropathic pain model, mental nerve chronic constriction, in rats. Both statins were able to abolish interleukin-1β expression in sciatic nerve triggered by nerve ligation. Additionally, quantitative analysis with Iba-1 and glial fibrillary acid protein immunoreactivity demonstrated that rosuvastatin and simvastatin significantly reduced the spinal microglial and astrocyte activation produced by sciatic nerve injury. The increase of interleukin-1β mRNA in the ipsilateral side of spinal cords was also reduced by the treatment of either statin. We identified a potential new application of statins in the treatment of neuropathic pain. The pain-alleviating effects of statins are likely attributable to their immunomodulatory effects.

  12. Neuroprotective potential of atorvastatin and simvastatin (HMG-CoA reductase inhibitors) against 6-hydroxydopamine (6-OHDA) induced Parkinson-like symptoms.

    PubMed

    Kumar, Anil; Sharma, Neha; Gupta, Amit; Kalonia, Harikesh; Mishra, Jitendriya

    2012-08-30

    Neuro-inflammation and oxidative stress plays a key role in the pathophysiology of Parkinson's disease (PD). Studies demonstrated that neuro-inflammation and associated infiltration of inflammatory cells into central nervous system are inhibited by 3-hydroxy-3-methyl glutaryl co-enzyme A (HMG-CoA) reductase inhibitors. Based on these experimental evidences, the present study has been designed to evaluate the neuroprotective effect of HMG-CoA reductase inhibitors (atorvastatin and simvastatin) against 6-hydroxydopamine (6-OHDA) induced unilateral lesion model of PD. In the present study, the animals were divided into nine groups (n=15 per group). Group I: Naive (without treatment); Group II: Sham (surgery performed, vehicle administered); Group III: Atorvastatin (20mg/kg); Group IV: Simvastatin (30 mg/kg); Group V: Control [Intrastriatal 6-OHDA (20 μg; single unilateral injection)]; Groups VI and VII: 6-OHDA (20 μg)+atorvastatin (10mg/kg and 20mg/kg) respectively; Groups VIII and IX: 6-OHDA (20 μg)+simvastatin (15 mg/kg and 30 mg/kg) respectively. Intrastriatal administration of 6-OHDA (20 μg; 4 μl of 5 μg/μl) significantly caused impairment in body weight, locomotor activity, rota-rod performance, oxidative defense and mitochondrial enzyme complex activity, and increase in the inflammatory cytokine levels (TNF-α and IL-6) as compared to naive animals. Atorvastatin (20mg/kg) and simvastatin (30 mg/kg) drug treatment significantly improved these behavioral and biochemical alterations restored mitochondrial enzyme complex activities and attenuated neuroinflammatory markers in 6-OHDA (20 μg) treated animals as compared to control group. The findings of the present study demonstrate the neuroprotective potential of statins in experimental model of 6-OHDA induced Parkinson like symptoms.

  13. Retargeting the management of hypercholesterolemia – focus on evolocumab

    PubMed Central

    Colletti, Alessandro; Derosa, Giuseppe; Cicero, Arrigo FG

    2016-01-01

    Hypercholesterolemia is one of the main risk factors for atherosclerosis and cardiovascular diseases. The treatment is based on the modification of the diet and lifestyle and if necessary on a pharmacological therapy. The most widely used drugs are the inhibitors of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (statins); nevertheless, many patients do not reach optimal levels of low-density lipoprotein-cholesterol (LDL-C) even with maximal dosage of statins (eventually associated to ezetimibe) or present side effects, which do not allow them to continue the treatment. Inhibitors of PCSK9 represent a new therapeutic approach for lowering LDL-C. Evolocumab and alirocumab are human monoclonal antibodies, which bind to extracellular PCSK9 and thus interfere with the degradation of low-density lipoprotein receptor. Evolocumab use is approved for the treatment of patients with heterozygous familial hypercholesterolemia (FH) and homozygous FH as an adjunct to diet and maximally tolerated statin therapy or for subjects with clinical atherosclerotic cardiovascular disease who require additional lowering of LDL-C. Phase III clinical trials have demonstrated the effectiveness of evolocumab (140 mg/every 2 weeks or 420 mg/month, via subcutaneous injection) in monotherapy and in combination with statins, in the treatment of patients intolerant to statins or with FH. In monotherapy, it reduces LDL-C by 55%, and its association with statins leads to a reduction of LDL-C by up to 63%–75%. Evolocumab has been demonstrated to be safe and well tolerated. Ongoing clinical trials are assessing the long-term effects of evolocumab on the incidence of cardiovascular risk, safety, and tolerability. This review resumes the available clinical evidence on the efficacy and safety of evolocumab, for which a relatively large amount of clinical data are currently available, and discusses the retargeting of cholesterol-lowering therapy in clinical practice. PMID:27660454

  14. Atorvastatin calcium inhibits phenotypic modulation of PDGF-BB-induced VSMCs via down-regulation the Akt signaling pathway.

    PubMed

    Chen, Shuang; Liu, Baoqin; Kong, Dehui; Li, Si; Li, Chao; Wang, Huaqin; Sun, Yingxian

    2015-01-01

    Plasticity of vascular smooth muscle cells (VSMCs) plays a central role in the onset and progression of proliferative vascular diseases. In adult tissue, VSMCs exist in a physiological contractile-quiescent phenotype, which is defined by lack of the ability of proliferation and migration, while high expression of contractile marker proteins. After injury to the vessel, VSMC shifts from a contractile phenotype to a pathological synthetic phenotype, associated with increased proliferation, migration and matrix secretion. It has been demonstrated that PDGF-BB is a critical mediator of VSMCs phenotypic switch. Atorvastatin calcium, a selective inhibitor of 3-hydroxy-3-methyl-glutaryl l coenzyme A (HMG-CoA) reductase, exhibits various protective effects against VSMCs. In this study, we investigated the effects of atorvastatin calcium on phenotype modulation of PDGF-BB-induced VSMCs and the related intracellular signal transduction pathways. Treatment of VSMCs with atorvastatin calcium showed dose-dependent inhibition of PDGF-BB-induced proliferation. Atorvastatin calcium co-treatment inhibited the phenotype modulation and cytoskeleton rearrangements and improved the expression of contractile phenotype marker proteins such as α-SM actin, SM22α and calponin in comparison with PDGF-BB alone stimulated VSMCs. Although Akt phosphorylation was strongly elicited by PDGF-BB, Akt activation was attenuated when PDGF-BB was co-administrated with atorvastatin calcium. In conclusion, atorvastatin calcium inhibits phenotype modulation of PDGF-BB-induced VSMCs and activation of the Akt signaling pathway, indicating that Akt might play a vital role in the modulation of phenotype.

  15. Hypolipidemic Effects of Alkaloids from Rhizoma Coptidis in Diet-Induced Hyperlipidemic Hamsters.

    PubMed

    He, Kai; Kou, Shuming; Zou, Zongyao; Hu, Yinran; Feng, Min; Han, Bing; Li, Xuegang; Ye, Xiaoli

    2016-05-01

    This study was conducted to evaluate the antihyperlipidemic activity of five major alkaloids in Rhizoma Coptidis using high-fat- and high-cholesterol-induced hyperlipidemic hamsters. Hyperlipidemic hamsters were treated with coptisine, berberine, jatrorrhizine, palmatine, epiberberine, and total Rhizoma Coptidis alkaloids with a dose of 46.7 mg/kg × day for 140 days. Serum total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total bile acids were examined after alkaloid treatment. The results showed that all therapy agents prevented body weight gain, reduced the serum total cholesterol, and increased the high-density lipoprotein cholesterol of hamsters. Berberine, jatrorrhizine, and total Rhizoma Coptidis alkaloids decreased the triglyceride level in hyperlipidemic hamsters, while coptisine, jatrorrhizine, palmatine, and total Rhizoma Coptidis alkaloids significantly suppressed the elevation of the low-density lipoprotein cholesterol level. The fecal excretion of bile acids was significantly elevated by berberine, coptisine, jatrorrhizine, palmatine, total Rhizoma Coptidis alkaloids, and orlistat. Notably, total Rhizoma Coptidis alkaloids possess a much stronger lipid-lowering effect than the pure Rhizoma Coptidis alkaloids. Quantitative reverse transcription-polymerase chain reaction analyses revealed that Rhizoma Coptidis alkaloids could retard the synthesis of cholesterol by downregulating the mRNA expression of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and accelerate the clearance of lipids by upregulating the low-density lipoprotein receptor, cholesterol 7α-hydroxylase, and uncoupling protein-2 expression. These findings highlight the critical role of Rhizoma Coptidis alkaloids in hyperlipidemia treatment. Thus, they need to be considered in future therapeutic approaches.

  16. Intravenous administration of pravastatin immediately after middle cerebral artery occlusion reduces cerebral oedema in spontaneously hypertensive rats.

    PubMed

    Mariucci, Giuseppina; Taha, Elena; Tantucci, Michela; Spaccatini, Cristiano; Tozzi, Alessandro; Ambrosini, Maria Vittoria

    2011-06-25

    3-hydroxy-3-methyl-glutaryl-coenzyme-A (HMG-CoA) reductase inhibitors (statins) have been shown to protect against ischemic stroke by mechanisms that are independent of lowering serum cholesterol levels. In this study we investigated the potential neuroprotective effect of a single i.v. treatment with four increasing doses of pravastatin on permanent occlusion of middle cerebral artery (MCAo) in spontaneously hypertensive rats. Pravastatin was given 10 min after MCAo and its effect was determined 24 h later. Treatment results were evaluated in terms of infarct volume, homolateral hemisphere oedema, glial fibrillary acid (GFAP), vimentin (Vim) and endothelial NO synthase (eNOS) immunoreactivity and TUNEL positivity. Cerebral levels of eNOS were measured by western blot analysis. Pravastatin did not reduce cerebral infarct while it mitigated homolateral hemisphere oedema in a dose-dependent manner with respect to controls. No differences among groups were found regarding GFAP and Vim immunoreactivity and TUNEL positivity. Instead, pravastatin-treated animals presented a more marked cerebral eNOS immunoreactivity as compared with controls. In agreement with immunohistochemistry, immunoblot revealed dose-dependent increases in cerebral levels of eNOS in pravastatin rats. Our data confirm statin neuroprotection in cerebral ischemia. In particular, it is of great interest that a single i.v. Pravastatin administration reduced cerebral oedema by upregulating eNOS expression/activity. This, by increasing vascular NO bioavailability, could have produced proximal vasodilation and contributed to reducing perfusional deficit. It is worthy stressing how important the anti-oedema action is that pravastatin seems to exert. Indeed, cerebral oedema, when widespread and beyond limits of physiological compensation, causes endocranic hypertension and additional cerebral damage over time.

  17. Statins Attenuate Helicobacter pylori CagA Translocation and Reduce Incidence of Gastric Cancer: In Vitro and Population-Based Case-Control Studies.

    PubMed

    Lin, Chun-Jung; Liao, Wei-Chih; Lin, Hwai-Jeng; Hsu, Yuan-Man; Lin, Cheng-Li; Chen, Yu-An; Feng, Chun-Lung; Chen, Chih-Jung; Kao, Min-Chuan; Lai, Chih-Ho; Kao, Chia-Hung

    2016-01-01

    Gastric cancer is the second leading cause of cancer-related death worldwide. The correlation of Helicobacter pylori and the etiology of gastric cancer was substantially certain. Cholesterol-rich microdomains (also called lipid rafts), which provide platforms for signaling, are associated with H. pylori-induced pathogenesis leading to gastric cancer. Patients who have been prescribed statins, inhibitors of 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase, have exhibited a reduced risk of several types of cancer. However, no studies have addressed the effect of statins on H. pylori-associated gastric cancer from the antineoplastic perspective. In this study, we showed that treatment of gastric epithelial cells with simvastatin reduced the level of cellular cholesterol and led to attenuation of translocation and phosphorylation of H. pylori cytotoxin-associated gene A (CagA), which is recognized as a major determinant of gastric cancer development. Additionally, a nationwide case-control study based on data from the Taiwanese National Health Insurance Research Database (NHIRD) was conducted. A population-based case-control study revealed that patients who used simvastatin exhibited a significantly reduced risk of gastric cancer (adjusted odds ratio (OR) = 0.76, 95% confidence interval (CI) = 0.70-0.83). In patients exhibiting H. pylori infection who were prescribed simvastatin, the adjusted OR for gastric cancer was 0.25 (95% CI = 0.12-0.50). Our results combined an in vitro study with a nationwide population analysis reveal that statin use might be a feasible approach to prevent H. pylori-associated gastric cancer.

  18. The mitochondrial unfolded protein response activator ATFS-1 protects cells from inhibition of the mevalonate pathway

    PubMed Central

    Rauthan, Manish; Ranji, Parmida; Aguilera Pradenas, Nataly; Pitot, Christophe; Pilon, Marc

    2013-01-01

    Statins are cholesterol-lowering drugs that inhibit 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase, the rate-limiting enzyme in the synthesis of cholesterol via the mevalonate pathway. This pathway also produces coenzyme Q (a component of the respiratory chain), dolichols (important for protein glycosylation), and isoprenoids (lipid moieties responsible for the membrane association of small GTPases). We previously showed that the nematode Caenorhabditis elegans is useful to study the noncholesterol effects of statins because its mevalonate pathway lacks the sterol synthesis branch but retains all other branches. Here, from a screen of 150,000 mutagenized genomes, we isolated four C. elegans mutants resistant to statins by virtue of gain-of-function mutations within the first six amino acids of the protein ATFS-1, the key regulator of the mitochondrial unfolded protein response that includes activation of the chaperones HSP-6 and HSP-60. The atfs-1 gain-of-function mutants are also resistant to ibandronate, an inhibitor of an enzyme downstream of HMG-CoA reductase, and to gliotoxin, an inhibitor acting on a subbranch of the pathway important for protein prenylation, and showed improved mitochondrial function and protein prenylation in the presence of statins. Additionally, preinduction of the mitochondrial unfolded protein response in wild-type worms using ethidium bromide or paraquat triggered statin resistance, and similar observations were made in Schizosaccharomyces pombe and in a mammalian cell line. We conclude that statin resistance through maintenance of mitochondrial homeostasis is conserved across species, and that the cell-lethal effects of statins are caused primarily through impaired protein prenylation that results in mitochondria dysfunction. PMID:23530189

  19. Effects of Erxian decoction, a Chinese medicinal formulation, on serum lipid profile in a rat model of menopause

    PubMed Central

    2011-01-01

    Background The prevalence and risk of cardiovascular disease increase after menopause in correlation with the progression of abnormality in the serum lipid profile and the deprivation of estrogen. Erxian decoction (EXD), a Chinese medicinal formulation for treating menopausal syndrome, stimulates ovarian estrogen biosynthesis. This study investigates whether EXD improves the serum lipid profile in a menopausal rat model. Methods Twenty-month-old female Sprague Dawley rats were treated with EXD and its constituent fractions. Premarin was administered for comparison. After eight weeks of treatment, rats were sacrificed and the serum levels of total cholesterol, triglyceride, high-density-lipoprotein cholesterol and low-density-lipoprotein cholesterol were determined. The hepatic protein levels of 3-hydroxy-3-methyl-glutaryl-CoA reductase and low-density-lipoprotein receptor were assessed with Western blot. Results The serum levels of total cholesterol and low-density-lipoprotein cholesterol were significantly lower in the EXD-treated group than in the constituent fractions of EXD or premarin groups. However, the serum levels of triglyceride and high-density-lipoprotein cholesterol were not significantly different from the control groups. Results from Western blot suggest that EXD significantly down-regulated the protein level of 3-hydroxy-3-methyl-glutaryl-CoA reductase and up-regulated low-density-lipoprotein receptor. Conclusion EXD improves serum lipid profile in a menopausal rat model through the suppression of the serum levels of total cholesterol and low-density-lipoprotein cholesterol, possibly through the down-regulation of the 3-hydroxy-3-methyl-glutaryl-CoA and up-regulation of the low-density-lipoprotein receptor. PMID:22047073

  20. Prebiotic syntheses of vitamin coenzymes: II. Pantoic acid, pantothenic acid, and the composition of coenzyme A

    NASA Technical Reports Server (NTRS)

    Miller, S. L.; Schlesinger, G.

    1993-01-01

    Pantoic acid can by synthesized in good prebiotic yield from isobutyraldehyde or alpha-ketoisovaleric acid + H2CO + HCN. Isobutyraldehyde is the Strecker precursor to valine and alpha-ketoisovaleric acid is the valine transamination product. Mg2+ and Ca2+ as well as several transition metals are catalysts for the alpha-ketoisovaleric acid reaction. Pantothenic acid is produced from pantoyl lactone (easily formed from pantoic acid) and the relatively high concentrations of beta-alanine that would be formed on drying prebiotic amino acid mixtures. There is no selectivity for this reaction over glycine, alanine, or gamma-amino butyric acid. The components of coenzyme A are discussed in terms of ease of prebiotic formation and stability and are shown to be plausible choices, but many other compounds are possible. The gamma-OH of pantoic acid needs to be capped to prevent decomposition of pantothenic acid. These results suggest that coenzyme A function was important in the earliest metabolic pathways and that the coenzyme A precursor contained most of the components of the present coenzyme.

  1. Acyl-coenzyme A:cholesterol acyltransferases

    PubMed Central

    Chang, Ta-Yuan; Li, Bo-Liang; Chang, Catherine C. Y.; Urano, Yasuomi

    2009-01-01

    The enzymes acyl-coenzyme A (CoA):cholesterol acyltransferases (ACATs) are membrane-bound proteins that utilize long-chain fatty acyl-CoA and cholesterol as substrates to form cholesteryl esters. In mammals, two isoenzymes, ACAT1 and ACAT2, encoded by two different genes, exist. ACATs play important roles in cellular cholesterol homeostasis in various tissues. This chapter summarizes the current knowledge on ACAT-related research in two areas: 1) ACAT genes and proteins and 2) ACAT enzymes as drug targets for atherosclerosis and for Alzheimer's disease. PMID:19141679

  2. Molecular diagnosis of coenzyme Q10 deficiency.

    PubMed

    Yubero, Delia; Montero, Raquel; Armstrong, Judith; Espinós, Carmen; Palau, Francesc; Santos-Ocaña, Carlos; Salviati, Leonardo; Navas, Placido; Artuch, Rafael

    2015-01-01

    Coenzyme Q10 (CoQ) deficiency syndromes comprise a growing number of neurological and extraneurological disorders. Primary-genetic but also secondary CoQ deficiencies have been reported. The biochemical determination of CoQ is a good tool for the rapid identification of CoQ deficiencies but does not allow the selection of candidate genes for molecular diagnosis. Moreover, the metabolic pathway for CoQ synthesis is an intricate and not well-understood process, where a large number of genes are implicated. Thus, only next-generation sequencing techniques (either genetic panels of whole-exome and -genome sequencing) are at present appropriate for a rapid and realistic molecular diagnosis of these syndromes. The potential treatability of CoQ deficiency strongly supports the necessity of a rapid molecular characterization of patients, since primary CoQ deficiencies may respond well to CoQ treatment.

  3. Converting molecular information of redox coenzymes via self-assembly.

    PubMed

    Morikawa, Masa-aki; Kimizuka, Nobuo

    2012-11-21

    β-Nicotinamide adenine dinucleotide (NAD(+)) and its reduced form NADH specifically interact with a cyanine dye in aqueous media, giving distinct spectral and nanostructural characteristics to which molecular information of constituent coenzymes are converted via self-assembly.

  4. Conformations of Diphosphopyridine Coenzymes upon Binding to Dehydrogenases

    PubMed Central

    Lee, Chi-Yu; Eichner, Ronald D.; Kaplan, Nathan O.

    1973-01-01

    The binding of oxidized as well as reduced coenzyme to some dehydrogenases has been studied under different concentration ratios and temperatures by nuclear magnetic resonance spectroscopy. A significant difference in the spectral behavior between DPN+ and DPNH upon binding is interpreted in terms of fast and slow on-off rates relative to the nuclear magnetic resonance time scale in the binding of these two coenzymes. Significant downfield shifts of DPN+ were observed upon binding, comparable in magnitude to those expected upon opening (destacking) of the coenzymes in the case of chicken-muscle and lobster-tail lactate dehydrogenase (EC 1.1.1.27) and yeast alchol dehydrogenase (EC 1.1.1.1.). A preliminary survey of several other dehydrogenases is consistent with these findings. In the case of 3-phosphoglyceraldehyde dehydrogenase, there is a possibility that the coenzyme exists in the folded form. PMID:4351183

  5. Specificity and biological distribution of coenzyme M (2-mercaptoethanesulfonic acid).

    PubMed Central

    Balch, W E; Wolfe, R S

    1979-01-01

    The specificity of the growth requirement of Methanobacterium ruminantium strain M1 for a new coenzyme, 2-mercaptoethanesulfonic acid (HS--CoM), was examined. A variety of derivatives, analogs, and potential biosynthetic precursors of coenzyme M were tested; only a restricted range of thioether, thioester, and thiocarbonate derivatives of the cofactor were found to replace the HS--CoM requirement. Bromoethanesulfonic acid (BrCH2CH2SO3-), a halogenated analog of HS--CoM, potently inhibited the growth response. No coenzyme was detectable in a wide range of nonmethanogenic eucaryotic tissues and procaryotic organisms. However, all methanogens available in pure culture exhibited high levels of coenzyme M which ranged from 0.3 to 16 nmol/mg of dry weight. PMID:104960

  6. J1 acylase, a glutaryl-7-aminocephalosporanic acid acylase from Bacillus laterosporus J1, is a member of the alpha/beta-hydrolase fold superfamily.

    PubMed

    Yau, Ming-Hon; Wang, Jun; Tsang, Paul W K; Fong, Wing-Ping

    2006-02-20

    J1 acylase, a glutaryl-7-aminocephalosporanic acid acylase (GCA) isolated from Bacillus laterosporus J1, has been conventionally grouped as the only member of class V GCA, although its amino acid sequence shares less than 10% identity with members of other classes of GCA. Instead, it shows higher sequence similarities with Rhodococcus sp. strain MB1 cocaine esterase (RhCocE) and Acetobacter turbidans alpha-amino acid ester hydrolase (AtAEH), members of the alpha/beta-hydrolase fold superfamily. Homology modeling and secondary structure prediction indicate that the N-terminal region of J1 acylase has an alpha/beta-hydrolase folding pattern. The catalytic triads in RhCocE and AtAEH were identified in J1 acylase as S125, D264 and H309. Mutations to alanine at these positions were found to completely inactivate the enzyme. These results suggest that J1 acylase is a member of the alpha/beta-hydrolase fold superfamily with a serine-histidine-aspartate catalytic triad.

  7. Better than Nature: Nicotinamide Biomimetics That Outperform Natural Coenzymes

    PubMed Central

    2016-01-01

    The search for affordable, green biocatalytic processes is a challenge for chemicals manufacture. Redox biotransformations are potentially attractive, but they rely on unstable and expensive nicotinamide coenzymes that have prevented their widespread exploitation. Stoichiometric use of natural coenzymes is not viable economically, and the instability of these molecules hinders catalytic processes that employ coenzyme recycling. Here, we investigate the efficiency of man-made synthetic biomimetics of the natural coenzymes NAD(P)H in redox biocatalysis. Extensive studies with a range of oxidoreductases belonging to the “ene” reductase family show that these biomimetics are excellent analogues of the natural coenzymes, revealed also in crystal structures of the ene reductase XenA with selected biomimetics. In selected cases, these biomimetics outperform the natural coenzymes. “Better-than-Nature” biomimetics should find widespread application in fine and specialty chemicals production by harnessing the power of high stereo-, regio-, and chemoselective redox biocatalysts and enabling reactions under mild conditions at low cost. PMID:26727612

  8. Biochemical Assessment of Coenzyme Q10 Deficiency

    PubMed Central

    Rodríguez-Aguilera, Juan Carlos; Cortés, Ana Belén; Fernández-Ayala, Daniel J. M.; Navas, Plácido

    2017-01-01

    Coenzyme Q10 (CoQ10) deficiency syndrome includes clinically heterogeneous mitochondrial diseases that show a variety of severe and debilitating symptoms. A multiprotein complex encoded by nuclear genes carries out CoQ10 biosynthesis. Mutations in any of these genes are responsible for the primary CoQ10 deficiency, but there are also different conditions that induce secondary CoQ10 deficiency including mitochondrial DNA (mtDNA) depletion and mutations in genes involved in the fatty acid β-oxidation pathway. The diagnosis of CoQ10 deficiencies is determined by the decrease of its content in skeletal muscle and/or dermal skin fibroblasts. Dietary CoQ10 supplementation is the only available treatment for these deficiencies that require a rapid and distinct diagnosis. Here we review methods for determining CoQ10 content by HPLC separation and identification using alternative approaches including electrochemical detection and mass spectrometry. Also, we review procedures to determine the CoQ10 biosynthesis rate using labeled precursors. PMID:28273876

  9. Biochemical Assessment of Coenzyme Q10 Deficiency.

    PubMed

    Rodríguez-Aguilera, Juan Carlos; Cortés, Ana Belén; Fernández-Ayala, Daniel J M; Navas, Plácido

    2017-03-05

    Coenzyme Q10 (CoQ10) deficiency syndrome includes clinically heterogeneous mitochondrial diseases that show a variety of severe and debilitating symptoms. A multiprotein complex encoded by nuclear genes carries out CoQ10 biosynthesis. Mutations in any of these genes are responsible for the primary CoQ10 deficiency, but there are also different conditions that induce secondary CoQ10 deficiency including mitochondrial DNA (mtDNA) depletion and mutations in genes involved in the fatty acid β-oxidation pathway. The diagnosis of CoQ10 deficiencies is determined by the decrease of its content in skeletal muscle and/or dermal skin fibroblasts. Dietary CoQ10 supplementation is the only available treatment for these deficiencies that require a rapid and distinct diagnosis. Here we review methods for determining CoQ10 content by HPLC separation and identification using alternative approaches including electrochemical detection and mass spectrometry. Also, we review procedures to determine the CoQ10 biosynthesis rate using labeled precursors.

  10. Clinical applications of coenzyme Q10.

    PubMed

    Garrido-Maraver, Juan; Cordero, Mario D; Oropesa-Avila, Manuel; Vega, Alejandro Fernandez; de la Mata, Mario; Pavon, Ana Delgado; Alcocer-Gomez, Elisabet; Calero, Carmen Perez; Paz, Marina Villanueva; Alanis, Macarena; de Lavera, Isabel; Cotan, David; Sanchez-Alcazar, Jose A

    2014-01-01

    Coenzyme Q10 (CoQ10) or ubiquinone was known for its key role in mitochondrial bioenergetics as electron and proton carrier; later studies demonstrated its presence in other cellular membranes and in blood plasma, and extensively investigated its antioxidant role. These two functions constitute the basis for supporting the clinical indication of CoQ10. Furthermore, recent data indicate that CoQ10 affects expression of genes involved in human cell signalling, metabolism and transport and some of the effects of CoQ10 supplementation may be due to this property. CoQ10 deficiencies are due to autosomal recessive mutations, mitochondrial diseases, ageing-related oxidative stress and carcinogenesis processes, and also a secondary effect of statin treatment. Many neurodegenerative disorders, diabetes, cancer, fibromyalgia, muscular and cardiovascular diseases have been associated with low CoQ10 levels. CoQ10 treatment does not cause serious adverse effects in humans and new formulations have been developed that increase CoQ10 absorption and tissue distribution. Oral CoQ10 treatment is a frequent mitochondrial energizer and antioxidant strategy in many diseases that may provide a significant symptomatic benefit.

  11. Statins: perspectives in cancer therapeutics.

    PubMed

    Corcos, Laurent; Le Jossic-Corcos, Catherine

    2013-10-01

    Virtually any cell type in a mammalian organism uses Acetyl CoA to yield mevalonate, through the activity of the 3-hydroxy-3-methyl-glutaryl-CoA reductase enzyme and, ultimately, cholesterol. Statins have long and quite successfully been used as cholesterol lowering drugs. They reversibly inhibit the 3-hydroxy-3-methyl-glutaryl-CoA reductase activity, which is rate limiting in the early steps of the cholesterol synthesis pathway. In addition to these effects, it has also been amply shown that statins may efficiently trigger cancer cell apoptosis, making them a plausible therapeutic option for the treatment of cancer. Whether statins may prevent cancer occurrence is a matter of debate and an unanswered question; undoubtedly experimental models have clearly demonstrated the potential of statins as direct cytotoxic agents, which can reduce tumour development or metastasis spread, even more so when combined with cytotoxic drugs. Until now, however, only few data in humans support the idea that statins could rightfully belong to the group of anticancer drugs. Nevertheless, as cancer cell metabolism is being thoroughly revisited, the mevalonate pathway has recently been reported as truly oncogenic, presenting the attractive possibility that mevalonate pathway inhibitors, such as statins, may join the ranks of anticancer drugs.

  12. Experimental evidence that bioenergetics disruption is not mainly involved in the brain injury of glutaryl-CoA dehydrogenase deficient mice submitted to lysine overload.

    PubMed

    Amaral, Alexandre Umpierrez; Cecatto, Cristiane; Seminotti, Bianca; Ribeiro, César Augusto; Lagranha, Valeska Lizzi; Pereira, Carolina Coffi; de Oliveira, Francine Hehn; de Souza, Diogo Gomes; Goodman, Stephen; Woontner, Michael; Wajner, Moacir

    2015-09-16

    Bioenergetics dysfunction has been postulated as an important pathomechanism of brain damage in glutaric aciduria type I, but this is still under debate. We investigated activities of citric acid cycle (CAC) enzymes, lactate release, respiration and membrane potential (ΔΨm) in mitochondrial preparations from cerebral cortex and striatum of 30-day-old glutaryl-CoA dehydrogenase deficient (Gcdh-/-) and wild type mice fed a baseline or a high lysine (Lys, 4.7%) chow for 60 or 96h. Brain histological analyses were performed in these animals, as well as in 90-day-old animals fed a baseline or a high Lys chow during 30 days starting at 60-day-old. A moderate reduction of citrate synthase and isocitrate dehydrogenase activities was observed only in the striatum from 30-day-old Gcdh-/- animals submitted to a high Lys chow. In contrast, the other CAC enzyme activities, lactate release, the respiratory parameters state 3, state 4, the respiratory control ratio and CCCP-stimulated (uncoupled) state, as well as ΔΨm were not altered in the striatum. Similarly, none of the evaluated parameters were changed in the cerebral cortex from these animals under baseline or Lys overload. On the other hand, histological analyses revealed the presence of intense vacuolation in the cerebral cortex of 60 and 90-day-old Gcdh-/- mice fed a baseline chow and in the striatum of 90-day-old Gcdh-/- mice submitted to Lys overload for 30 days. Taken together, the present data demonstrate mild impairment of bioenergetics homeostasis and marked histological alterations in striatum from Gcdh-/- mice under a high Lys chow, suggesting that disruption of energy metabolism is not mainly involved in the brain injury of these animals.

  13. Invertebrate Models for Coenzyme Q10 Deficiency

    PubMed Central

    Fernández-Ayala, Daniel J.M.; Jiménez-Gancedo, Sandra; Guerra, Ignacio; Navas, Plácido

    2014-01-01

    The human syndrome of coenzyme Q (CoQ) deficiency is a heterogeneous mitochondrial disease characterized by a diminution of CoQ content in cells and tissues that affects all the electron transport processes CoQ is responsible for, like the electron transference in mitochondria for respiration and ATP production and the antioxidant capacity that it exerts in membranes and lipoproteins. Supplementation with external CoQ is the main attempt to address these pathologies, but quite variable results have been obtained ranging from little response to a dramatic recovery. Here, we present the importance of modeling human CoQ deficiencies in animal models to understand the genetics and the pathology of this disease, although the election of an organism is crucial and can sometimes be controversial. Bacteria and yeast harboring mutations that lead to CoQ deficiency are unable to grow if they have to respire but develop without any problems on media with fermentable carbon sources. The complete lack of CoQ in mammals causes embryonic lethality, whereas other mutations produce tissue-specific diseases as in humans. However, working with transgenic mammals is time and cost intensive, with no assurance of obtaining results. Caenorhabditis elegans and Drosophila melanogaster have been used for years as organisms to study embryonic development, biogenesis, degenerative pathologies, and aging because of the genetic facilities and the speed of working with these animal models. In this review, we summarize several attempts to model reliable human CoQ deficiencies in invertebrates, focusing on mutant phenotypes pretty similar to those observed in human patients. PMID:25126050

  14. Coenzyme Q10 in the diet--daily intake and relative bioavailability.

    PubMed

    Weber, C; Bysted, A; Hølmer, G

    1997-01-01

    The coenzyme Q10 content of the average Danish diet was estimated from consumption data and from analysis of food items to be 3-5 mg coenzyme Q10 per day, primarily derived (64% of the total) from meat and poultry. To investigate if coenzyme Q10 was absorbed to any significant degree from a food item, a randomized cross-over study with single doses of coenzyme Q10 (30 mg/person), administered either as a meal or as capsules, was carried out in healthy subjects. The serum coenzyme Q10 concentration increased significantly, and the maximum concentrations did not differ significantly for the two forms of administration. The study indicates that coenzyme Q10 is present in food items and absorbed to a significant degree. Thus, dietary coenzyme Q10 may contribute to the plasma coenzyme Q10 concentration.

  15. Genetic Confirmation of the Role of Sulfopyruvate Decarboxylase in Coenzyme M Biosynthesis in Methanococcus maripaludis

    DOE PAGES

    Sarmiento, Felipe; Ellison, Courtney K.; Whitman, William B.

    2013-01-01

    Coenzyme M is an essential coenzyme for methanogenesis. The proposed biosynthetic pathway consists of five steps, of which the fourth step is catalyzed by sulfopyruvate decarboxylase (ComDE). Disruption of the gene comE by transposon mutagenesis resulted in a partial coenzyme M auxotroph, which grew poorly in the absence of coenzyme M and retained less than 3% of the wild type level of coenzyme M biosynthesis. Upon coenzyme M addition, normal growth of the mutant was restored. Moreover, complementation of the mutation with the wild type comE gene in trans restored full growth in the absence of coenzyme M. Thesemore » results confirm that ComE plays an important role in coenzyme M biosynthesis. The inability to yield a complete CoM auxotroph suggests that either the transposon insertion failed to completely inactivate the gene or M. maripaludis possesses a promiscuous activity that partially complemented the mutation.« less

  16. Identification of 3-Sulfinopropionyl Coenzyme A (CoA) Desulfinases within the Acyl-CoA Dehydrogenase Superfamily

    PubMed Central

    Schürmann, Marc; Demming, Rebecca Michaela; Krewing, Marco; Rose, Judith; Wübbeler, Jan Hendrik

    2014-01-01

    In a previous study, the essential role of 3-sulfinopropionyl coenzyme A (3SP-CoA) desulfinase acyl-CoA dehydrogenase (Acd) in Advenella mimigardefordensis strain DPN7T (AcdDPN7) during degradation of 3,3′-dithiodipropionic acid (DTDP) was elucidated. DTDP is a sulfur-containing precursor substrate for biosynthesis of polythioesters (PTEs). AcdDPN7 showed high amino acid sequence similarity to acyl-CoA dehydrogenases but was unable to catalyze a dehydrogenation reaction. Hence, it was investigated in the present study whether 3SP-CoA desulfinase activity is an uncommon or a widespread property within the acyl-CoA dehydrogenase superfamily. Therefore, proteins of the acyl-CoA dehydrogenase superfamily from Advenella kashmirensis WT001, Bacillus cereus DSM31, Cupriavidus necator N-1, Escherichia coli BL21, Pseudomonas putida KT2440, Burkholderia xenovorans LB400, Ralstonia eutropha H16, Variovorax paradoxus B4, Variovorax paradoxus S110, and Variovorax paradoxus TBEA6 were expressed in E. coli strains. All purified acyl-CoA dehydrogenases appeared as homotetramers, as revealed by size exclusion chromatography. AcdS110, AcdB4, AcdH16, and AcdKT2440 were able to dehydrogenate isobutyryl-CoA. AcdKT2440 additionally dehydrogenated butyryl-CoA and valeryl-CoA, whereas AcdDSM31 dehydrogenated only butyryl-CoA and valeryl-CoA. No dehydrogenation reactions were observed with propionyl-CoA, isovaleryl-CoA, succinyl-CoA, and glutaryl-CoA for any of the investigated acyl-CoA dehydrogenases. Only AcdTBEA6, AcdN-1, and AcdLB400 desulfinated 3SP-CoA and were thus identified as 3SP-CoA desulfinases within the acyl-CoA dehydrogenase family, although none of these three Acds dehydrogenated any of the tested acyl-CoA thioesters. No appropriate substrates were identified for AcdBL21 and AcdWT001. Spectrophotometric assays provided apparent Km and Vmax values for active substrates and indicated the applicability of phylogenetic analyses to predict the substrate range of

  17. Identification of 3-sulfinopropionyl coenzyme A (CoA) desulfinases within the Acyl-CoA dehydrogenase superfamily.

    PubMed

    Schürmann, Marc; Demming, Rebecca Michaela; Krewing, Marco; Rose, Judith; Wübbeler, Jan Hendrik; Steinbüchel, Alexander

    2014-02-01

    In a previous study, the essential role of 3-sulfinopropionyl coenzyme A (3SP-CoA) desulfinase acyl-CoA dehydrogenase (Acd) in Advenella mimigardefordensis strain DPN7(T) (AcdDPN7) during degradation of 3,3'-dithiodipropionic acid (DTDP) was elucidated. DTDP is a sulfur-containing precursor substrate for biosynthesis of polythioesters (PTEs). AcdDPN7 showed high amino acid sequence similarity to acyl-CoA dehydrogenases but was unable to catalyze a dehydrogenation reaction. Hence, it was investigated in the present study whether 3SP-CoA desulfinase activity is an uncommon or a widespread property within the acyl-CoA dehydrogenase superfamily. Therefore, proteins of the acyl-CoA dehydrogenase superfamily from Advenella kashmirensis WT001, Bacillus cereus DSM31, Cupriavidus necator N-1, Escherichia coli BL21, Pseudomonas putida KT2440, Burkholderia xenovorans LB400, Ralstonia eutropha H16, Variovorax paradoxus B4, Variovorax paradoxus S110, and Variovorax paradoxus TBEA6 were expressed in E. coli strains. All purified acyl-CoA dehydrogenases appeared as homotetramers, as revealed by size exclusion chromatography. AcdS110, AcdB4, AcdH16, and AcdKT2440 were able to dehydrogenate isobutyryl-CoA. AcdKT2440 additionally dehydrogenated butyryl-CoA and valeryl-CoA, whereas AcdDSM31 dehydrogenated only butyryl-CoA and valeryl-CoA. No dehydrogenation reactions were observed with propionyl-CoA, isovaleryl-CoA, succinyl-CoA, and glutaryl-CoA for any of the investigated acyl-CoA dehydrogenases. Only AcdTBEA6, AcdN-1, and AcdLB400 desulfinated 3SP-CoA and were thus identified as 3SP-CoA desulfinases within the acyl-CoA dehydrogenase family, although none of these three Acds dehydrogenated any of the tested acyl-CoA thioesters. No appropriate substrates were identified for AcdBL21 and AcdWT001. Spectrophotometric assays provided apparent Km and Vmax values for active substrates and indicated the applicability of phylogenetic analyses to predict the substrate range of

  18. Structural Insight into Methyl-Coenzyme M Reductase Chemistry Using Coenzyme B Analogues

    SciTech Connect

    Cedervall, Peder E.; Dey, Mishtu; Pearson, Arwen R.; Ragsdale, Stephen W.; Wilmot, Carrie M.

    2010-09-07

    Methyl-coenzyme M reductase (MCR) catalyzes the final and rate-limiting step in methane biogenesis: the reduction of methyl-coenzyme M (methyl-SCoM) by coenzyme B (CoBSH) to methane and a heterodisulfide (CoBS-SCoM). Crystallographic studies show that the active site is deeply buried within the enzyme and contains a highly reduced nickel-tetrapyrrole, coenzyme F430. Methyl-SCoM must enter the active site prior to CoBSH, as species derived from methyl-SCoM are always observed bound to the F430 nickel in the deepest part of the 30 {angstrom} long substrate channel that leads from the protein surface to the active site. The seven-carbon mercaptoalkanoyl chain of CoBSH binds within a 16 {angstrom} predominantly hydrophobic part of the channel close to F430, with the CoBSH thiolate lying closest to the nickel at a distance of 8.8 {angstrom}. It has previously been suggested that binding of CoBSH initiates catalysis by inducing a conformational change that moves methyl-SCoM closer to the nickel promoting cleavage of the C-S bond of methyl-SCoM. In order to better understand the structural role of CoBSH early in the MCR mechanism, we have determined crystal structures of MCR in complex with four different CoBSH analogues: pentanoyl, hexanoyl, octanoyl, and nonanoyl derivatives of CoBSH (CoB5SH, CoB6SH, CoB8SH, and CoB9SH, respectively). The data presented here reveal that the shorter CoB5SH mercaptoalkanoyl chain overlays with that of CoBSH but terminates two units short of the CoBSH thiolate position. In contrast, the mercaptoalkanoyl chain of CoB6SH adopts a different conformation, such that its thiolate is coincident with the position of the CoBSH thiolate. This is consistent with the observation that CoB6SH is a slow substrate. A labile water in the substrate channel was found to be a sensitive indicator for the presence of CoBSH and HSCoM. The longer CoB8SH and CoB9SH analogues can be accommodated in the active site through exclusion of this water. These analogues

  19. The M405V allele of the glutaryl-CoA dehydrogenase gene is an important marker for glutaric aciduria type I (GA-I) low excretors.

    PubMed

    Schillaci, Lori-Anne P; Greene, Carol L; Strovel, Erin; Rispoli-Joines, Jessica; Spector, Elaine; Woontner, Michael; Scharer, Gunter; Enns, Gregory M; Gallagher, Renata; Zinn, Arthur B; McCandless, Shawn E; Hoppel, Charles L; Goodman, Stephen I; Bedoyan, Jirair K

    2016-09-01

    Glutaric aciduria type I (GA-I) is an autosomal recessive organic aciduria resulting from a functional deficiency of glutaryl-CoA dehydrogenase, encoded by GCDH. Two clinically indistinguishable diagnostic subgroups of GA-I are known; low and high excretors (LEs and HEs, respectively). Early medical and dietary interventions can result in significantly better outcomes and improved quality of life for patients with GA-I. We report on nine cases of GA-I LE patients all sharing the M405V allele with two cases missed by newborn screening (NBS) using tandem mass spectrometry (MS/MS). We describe a novel case with the known pathogenic M405V variant and a novel V133L variant, and present updated and previously unreported clinical, biochemical, functional and molecular data on eight other patients all sharing the M405V allele. Three of the nine patients are of African American ancestry, with two as siblings. GCDH activity was assayed in six of the nine patients and varied from 4 to 25% of the control mean. We support the use of urine glutarylcarnitine as a biochemical marker of GA-I by demonstrating that glutarylcarnitine is efficiently cleared by the kidney (50-90%) and that plasma and urine glutarylcarnitine follow a linear relationship. We report the allele frequencies for three known GA-I LE GCDH variants (M405V, V400M and R227P) and note that both the M405V and V400M variants are significantly more common in the population of African ancestry compared to the general population. This report highlights the M405V allele as another important molecular marker in patients with the GA-I LE phenotype. Therefore, the incorporation into newborn screening of molecular screening for the M405V and V400M variants in conjunction with MS/MS could help identify asymptomatic at-risk GA-I LE patients that could potentially be missed by current NBS programs.

  20. Investigating the coenzyme specificity of phenylacetone monooxygenase from Thermobifida fusca.

    PubMed

    Dudek, Hanna M; Torres Pazmiño, Daniel E; Rodríguez, Cristina; de Gonzalo, Gonzalo; Gotor, Vicente; Fraaije, Marco W

    2010-11-01

    Type I Baeyer-Villiger monooxygenases (BVMOs) strongly prefer NADPH over NADH as an electron donor. In order to elucidate the molecular basis for this coenzyme specificity, we have performed a site-directed mutagenesis study on phenylacetone monooxygenase (PAMO) from Thermobifida fusca. Using sequence alignments of type I BVMOs and crystal structures of PAMO and cyclohexanone monooxygenase in complex with NADP(+), we identified four residues that could interact with the 2'-phosphate moiety of NADPH in PAMO. The mutagenesis study revealed that the conserved R217 is essential for binding the adenine moiety of the nicotinamide coenzyme while it also contributes to the recognition of the 2'-phosphate moiety of NADPH. The substitution of T218 did not have a strong effect on the coenzyme specificity. The H220N and H220Q mutants exhibited a ~3-fold improvement in the catalytic efficiency with NADH while the catalytic efficiency with NADPH was hardly affected. Mutating K336 did not increase the activity of PAMO with NADH, but it had a significant and beneficial effect on the enantioselectivity of Baeyer-Villiger oxidations and sulfoxidations. In conclusion, our results indicate that the function of NADPH in catalysis cannot be easily replaced by NADH. This finding is in line with the complex catalytic mechanism and the vital role of the coenzyme in BVMOs.

  1. [Distribution of ubiquinones (coenzyme Q) in Gram negative bacillae].

    PubMed

    Denis, F A; D'Oultremont, P A; Debacq, J J; Cherel, J M; Brisou, J

    1975-01-01

    The coenzyme Q system was examined on 55 strains of Gram negative aerobic or facultatively anaerobic rods. No bacteria contain Co-Q7 nor Co-Q10. Ubiquinone Q8 predominates in Flavobacterium and in Enterobacteriaceae; Q9 was the only homolog found in the Pseudomonas, and predominates in the Acinetobacter.

  2. Investigating the coenzyme specificity of phenylacetone monooxygenase from Thermobifida fusca

    PubMed Central

    Dudek, Hanna M.; Torres Pazmiño, Daniel E.; Rodríguez, Cristina; de Gonzalo, Gonzalo; Gotor, Vicente

    2010-01-01

    Type I Baeyer–Villiger monooxygenases (BVMOs) strongly prefer NADPH over NADH as an electron donor. In order to elucidate the molecular basis for this coenzyme specificity, we have performed a site-directed mutagenesis study on phenylacetone monooxygenase (PAMO) from Thermobifida fusca. Using sequence alignments of type I BVMOs and crystal structures of PAMO and cyclohexanone monooxygenase in complex with NADP+, we identified four residues that could interact with the 2′-phosphate moiety of NADPH in PAMO. The mutagenesis study revealed that the conserved R217 is essential for binding the adenine moiety of the nicotinamide coenzyme while it also contributes to the recognition of the 2′-phosphate moiety of NADPH. The substitution of T218 did not have a strong effect on the coenzyme specificity. The H220N and H220Q mutants exhibited a ~3-fold improvement in the catalytic efficiency with NADH while the catalytic efficiency with NADPH was hardly affected. Mutating K336 did not increase the activity of PAMO with NADH, but it had a significant and beneficial effect on the enantioselectivity of Baeyer–Villiger oxidations and sulfoxidations. In conclusion, our results indicate that the function of NADPH in catalysis cannot be easily replaced by NADH. This finding is in line with the complex catalytic mechanism and the vital role of the coenzyme in BVMOs. PMID:20703875

  3. Coenzyme Q10 Administration Increases Brain Mitochondrial Concentrations and Exerts Neuroprotective Effects

    NASA Astrophysics Data System (ADS)

    Matthews, Russell T.; Yang, Lichuan; Browne, Susan; Baik, Myong; Flint Beal, M.

    1998-07-01

    Coenzyme Q10 is an essential cofactor of the electron transport chain as well as a potent free radical scavenger in lipid and mitochondrial membranes. Feeding with coenzyme Q10 increased cerebral cortex concentrations in 12- and 24-month-old rats. In 12-month-old rats administration of coenzyme Q10 resulted in significant increases in cerebral cortex mitochondrial concentrations of coenzyme Q10. Oral administration of coenzyme Q10 markedly attenuated striatal lesions produced by systemic administration of 3-nitropropionic acid and significantly increased life span in a transgenic mouse model of familial amyotrophic lateral sclerosis. These results show that oral administration of coenzyme Q10 increases both brain and brain mitochondrial concentrations. They provide further evidence that coenzyme Q10 can exert neuroprotective effects that might be useful in the treatment of neurodegenerative diseases.

  4. Reconstitution and properties of a coenzyme F420-mediated formate hydrogenlyase system in Methanobacterium formicicum.

    PubMed Central

    Baron, S F; Ferry, J G

    1989-01-01

    Formate hydrogenlyase activity in a cell extract of Methanobacterium formicicum was abolished by removal of coenzyme F420; addition of purified coenzyme F420 restored activity. Formate hydrogenlyase activity was reconstituted with three purified components from M. formicicum: coenzyme F420-reducing hydrogenase, coenzyme F420-reducing formate dehydrogenase, and coenzyme F420. The reconstituted system required added flavin adenine dinucleotide (FAD) for maximal activity. Without FAD, the formate dehydrogenase and hydrogenase rapidly lost coenzyme F420-dependent activity relative to methyl viologen-dependent activity. Immunoadsorption of formate dehydrogenase or coenzyme F420-reducing hydrogenase from the cell extract greatly reduced formate hydrogenlyase activity; addition of the purified enzymes restored activity. The formate hydrogenlyase activity was reversible, since both the cell extract and the reconstituted system produced formate from H2 plus CO2 and HCO3-. PMID:2661536

  5. A eubacterial riboswitch class that senses the coenzyme tetrahydrofolate.

    PubMed

    Ames, Tyler D; Rodionov, Dmitry A; Weinberg, Zasha; Breaker, Ronald R

    2010-07-30

    Comparative sequence analyses of bacterial genomes are revealing many structured RNA motifs that function as metabolite-binding riboswitches. We have identified an RNA motif frequently positioned in the 5' UTRs of folate transport and biosynthesis genes in Firmicute genomes. Biochemical experiments confirm that representatives of this new-found RNA class selectively bind derivatives of the vitamin folate, including di- and tetrahydrofolate coenzymes. In addition, representatives of this aptamer class occasionally reside upstream of RNA structures that are predicted to control translation initiation in response to ligand binding. These findings expand the number of coenzymes that are directly sensed by RNA and reveal possible riboswitch-controlled regulons that respond to changes in single-carbon metabolism.

  6. Linkage between coenzyme a metabolism and inflammation: roles of pantetheinase.

    PubMed

    Nitto, Takeaki; Onodera, Kenji

    2013-09-20

    Pantetheinase is an enzyme hydrolyzing pantetheine, an intermediate of the coenzyme A degradation pathway. Pantetheinase has long been considered as the enzyme that recycles pantothenic acid (vitamin B5) generated during coenzyme A breakdown. Genetic analyses showed that mammals have multiple genes known as vanin family genes. Recent studies using mice lacking the vanin-1 gene (pantetheinase gene) suggest that pantetheinase is actively involved in the progression of inflammatory reactions by generating cysteamine. Additional studies using human leukocytes demonstrate that human neutrophils have abundant pantetheinase proteins on the surface and inside the cells. The second pantetheinase protein, GPI-80/VNN2, is suggested to work as a modulator of the function of Mac-1 (CD11b/CD18), an adhesion molecule important to neutrophil functions. This review delineates the characteristics of the pantetheinase/vanin gene family and how they affect inflammation.

  7. Mitofusin 2 is required to maintain mitochondrial coenzyme Q levels

    PubMed Central

    Mourier, Arnaud; Motori, Elisa; Brandt, Tobias; Lagouge, Marie; Atanassov, Ilian; Galinier, Anne; Rappl, Gunter; Brodesser, Susanne; Hultenby, Kjell; Dieterich, Christoph

    2015-01-01

    Mitochondria form a dynamic network within the cell as a result of balanced fusion and fission. Despite the established role of mitofusins (MFN1 and MFN2) in mitochondrial fusion, only MFN2 has been associated with metabolic and neurodegenerative diseases, which suggests that MFN2 is needed to maintain mitochondrial energy metabolism. The molecular basis for the mitochondrial dysfunction encountered in the absence of MFN2 is not understood. Here we show that loss of MFN2 leads to impaired mitochondrial respiration and reduced ATP production, and that this defective oxidative phosphorylation process unexpectedly originates from a depletion of the mitochondrial coenzyme Q pool. Our study unravels an unexpected and novel role for MFN2 in maintenance of the terpenoid biosynthesis pathway, which is necessary for mitochondrial coenzyme Q biosynthesis. The reduced respiratory chain function in cells lacking MFN2 can be partially rescued by coenzyme Q10 supplementation, which suggests a possible therapeutic strategy for patients with diseases caused by mutations in the Mfn2 gene. PMID:25688136

  8. Thermophilic archaea activate butane via alkyl-coenzyme M formation.

    PubMed

    Laso-Pérez, Rafael; Wegener, Gunter; Knittel, Katrin; Widdel, Friedrich; Harding, Katie J; Krukenberg, Viola; Meier, Dimitri V; Richter, Michael; Tegetmeyer, Halina E; Riedel, Dietmar; Richnow, Hans-Hermann; Adrian, Lorenz; Reemtsma, Thorsten; Lechtenfeld, Oliver J; Musat, Florin

    2016-11-17

    The anaerobic formation and oxidation of methane involve unique enzymatic mechanisms and cofactors, all of which are believed to be specific for C1-compounds. Here we show that an anaerobic thermophilic enrichment culture composed of dense consortia of archaea and bacteria apparently uses partly similar pathways to oxidize the C4 hydrocarbon butane. The archaea, proposed genus 'Candidatus Syntrophoarchaeum', show the characteristic autofluorescence of methanogens, and contain highly expressed genes encoding enzymes similar to methyl-coenzyme M reductase. We detect butyl-coenzyme M, indicating archaeal butane activation analogous to the first step in anaerobic methane oxidation. In addition, Ca. Syntrophoarchaeum expresses the genes encoding β-oxidation enzymes, carbon monoxide dehydrogenase and reversible C1 methanogenesis enzymes. This allows for the complete oxidation of butane. Reducing equivalents are seemingly channelled to HotSeep-1, a thermophilic sulfate-reducing partner bacterium known from the anaerobic oxidation of methane. Genes encoding 16S rRNA and methyl-coenzyme M reductase similar to those identifying Ca. Syntrophoarchaeum were repeatedly retrieved from marine subsurface sediments, suggesting that the presented activation mechanism is naturally widespread in the anaerobic oxidation of short-chain hydrocarbons.

  9. Coenzyme A and its derivatives: renaissance of a textbook classic.

    PubMed

    Theodoulou, Frederica L; Sibon, Ody C M; Jackowski, Suzanne; Gout, Ivan

    2014-08-01

    In 1945, Fritz Lipmann discovered a heat-stable cofactor required for many enzyme-catalysed acetylation reactions. He later determined the structure for this acetylation coenzyme, or coenzyme A (CoA), an achievement for which he was awarded the Nobel Prize in 1953. CoA is now firmly embedded in the literature, and in students' minds, as an acyl carrier in metabolic reactions. However, recent research has revealed diverse and important roles for CoA above and beyond intermediary metabolism. As well as participating in direct post-translational regulation of metabolic pathways by protein acetylation, CoA modulates the epigenome via acetylation of histones. The organization of CoA biosynthetic enzymes into multiprotein complexes with different partners also points to close linkages between the CoA pool and multiple signalling pathways. Dysregulation of CoA biosynthesis or CoA thioester homoeostasis is associated with various human pathologies and, although the biochemistry of CoA biosynthesis is highly conserved, there are significant sequence and structural differences between microbial and human biosynthetic enzymes. Therefore the CoA biosynthetic pathway is an attractive target for drug discovery. The purpose of the Coenzyme A and Its Derivatives in Cellular Metabolism and Disease Biochemical Society Focused Meeting was to bring together researchers from around the world to discuss the most recent advances on the influence of CoA, its biosynthetic enzymes and its thioesters in cellular metabolism and diseases and to discuss challenges and opportunities for the future.

  10. Autotrophic acetyl coenzyme A biosynthesis in Methanococcus maripaludis.

    PubMed Central

    Shieh, J; Whitman, W B

    1988-01-01

    To detect autotrophic CO2 assimilation in cell extracts of Methanococcus maripaludis, lactate dehydrogenase and NADH were added to convert pyruvate formed from autotrophically synthesized acetyl coenzyme A to lactate. The lactate produced was determined spectrophotometrically. When CO2 fixation was pulled in the direction of lactate synthesis, CO2 reduction to methane was inhibited. Bromoethanesulfonate (BES), a potent inhibitor of methanogenesis, enhanced lactate synthesis, and methyl coenzyme M inhibited it in the absence of BES. Lactate synthesis was dependent on CO2 and H2, but H2 + CO2-independent synthesis was also observed. In cell extracts, the rate of lactate synthesis was about 1.2 nmol min-1 mg of protein-1. When BES was added, the rate of lactate synthesis increased to 2.3 nmol min-1 mg of protein-1. Because acetyl coenzyme A did not stimulate lactate synthesis, pyruvate synthase may have been the limiting activity in these assays. Radiolabel from 14CO2 was incorporated into lactate. The percentages of radiolabel in the C-1, C-2, and C-3 positions of lactate were 73, 33, and 11%, respectively. Both carbon monoxide and formaldehyde stimulated lactate synthesis. 14CH2O was specifically incorporated into the C-3 of lactate, and 14CO was incorporated into the C-1 and C-2 positions. Low concentrations of cyanide also inhibited autotrophic growth, CO dehydrogenase activity, and autotrophic lactate synthesis. These observations are in agreement with the acetogenic pathway of autotrophic CO2 assimilation. PMID:3133359

  11. Breeding of Coenzyme Q10 Produced Strain by Low-Energy Ion Implantation and Optimization of Coenzyme Q10 Fermentation

    NASA Astrophysics Data System (ADS)

    Xu, Dejun; Zheng, Zhiming; Wang, Peng; Wang, Li; Yuan, Hang; Yu, Zengliang

    2008-12-01

    In order to increase the production efficiency of coenzyme Q10, the original strain Agrobacterium tumefaciens ATCC 4452 was mutated by means of Nitrogen ions implantation. A mutant strain, ATX 12, with high contents of coenzyme Q10 was selected. Subsequently, the conditions such as carbohydrate concentration, nitrogen source concentration, inoculum's size, seed age, aeration and temperature which might affect the production of CoQ10 were investigated in detail. Under optimal conditions, the maximum concentration of the intracellular CoQ10 reached 200.3 mg/L after 80 h fed-batch fermentation, about 245% increasing in CoQ10 production after ion implantation, compared to the original strain.

  12. Simultaneous high-performance liquid chromatography determination of coenzyme A, dephospho-coenzyme A, and acetyl-coenzyme A in normal and pantothenic acid-deficient rats.

    PubMed

    Shibata, Katsumi; Nakai, Takumi; Fukuwatari, Tsutomu

    2012-11-15

    We describe here a simultaneous high-performance liquid chromatography method for practical and rapid determination of coenzyme A (CoA), dephospho-CoA, and acetyl-CoA in tissues. These coenzymes are biosynthesized from the vitamin pantothenic acid (PaA), which is involved in the metabolism of fatty acids, amino acid catabolism, and several other nutrients. The method employed a Tosoh TSK-GEL ODS-100 V column (250×4.6mm i.d., particle size 5μm) eluted with 100mmol/L NaH(2)PO(4) and 75mmol/L CH(3)COONa (pH was adjusted to 4.6 by the addition of concentrated H(3)PO(4))-acetonitrile (94:6, v/v) at a flow rate of 1.0ml/min. The ultraviolet detector was set at 259nm. The limits of detection for CoA, dephospho-CoA, and acetyl-CoA all were 10pmol. The method was applied to the analysis of several tissues of rats fed normal and PaA-free diets. The results clearly showed that the method was suitable for the simultaneous determination of CoA, dephospho-CoA, and acetyl-CoA in the liver, heart, kidney, spleen, testis, large colon, and muscle, but not for the small intestine, of rats.

  13. Thermodynamic and structural properties of Eu3+ complexes of a new 12-membered tetraaza macrocycle containing pyridine and N-glutaryl groups as pendant arms: characterization of three complexing successive phases.

    PubMed

    Moreau, Juliette; Pierrard, Jean-Claude; Rimbault, Jean; Guillon, Emmanuel; Port, Marc; Aplincourt, Michel

    2007-04-28

    A new polyazamacrocyclic ligand (called pctga) containing pyridine and N-glutaryl arms has been synthesized as a potential agent for MRI (magnetic resonance imaging). Three series of successive complexes formed with Eu(3+) were characterized by at least two of the following methods: potentiometry, EXAFS or luminescence spectrometry. In the immediate complexes [EuH(h)(pctga)(H2O)6](h-3)+**, the metal ion is bound to the oxygen atoms of the three internal carboxylate groups and to six water molecules. As the lanthanide moves into the macrocyclic cavity, these species rapidly evolve into the intermediate metastable complexes [EuH(h)(pctga)(H2O)4](h-3)+*. The formation of two new bonds with the nitrogen atoms of the tetraazamacrocycle decreased the number of coordinated water molecules to four. In the final thermodynamically stable complexes [EuH(h)(pctga)(H2O)(2)](h-3)+, the pctga is bound to the europium(III) in a heptadentate manner, via the four nitrogen atoms of the tetraazamacrocycle and the three oxygen atoms of the internal carboxylate groups. The coordination number of the metal ion is completed to nine with two inner-sphere water molecules. The mean hydration numbers were calculated from the values of the bimolecular quenching constant k(q) of the luminescence species. The thermodynamic parameters corresponding to the protonation constants of the ligand and to the formation constants of the various intermediate and final complexes were determined from potentiometric measurements. They show that the complex species have some specific thermodynamic and structural properties inherent to the N-glutaryl groups and to the pyridine cycle. The insertion of this aromatic substructure rigidifies the ligand and sensibly diminishes the value of the overall formation constant (log beta(110) = 18.66(5)). This whole study allows us to propose a complexation mechanism for the system Eu(3+)/pctga in solution which is a mixture of the ones determined for the ligands dota and

  14. Potential role of coenzyme Q10 in facilitating recovery from statin-induced rhabdomyolysis.

    PubMed

    Wang, L W; Jabbour, A; Hayward, C S; Furlong, T J; Girgis, L; Macdonald, P S; Keogh, A M

    2015-04-01

    Rhabdomyolysis is a rare, but serious complication of statin therapy, and represents the most severe end of the spectrum of statin-induced myotoxicity. We report a case where coenzyme Q10 facilitated recovery from statin-induced rhabdomyolysis and acute renal failure, which had initially persisted despite statin cessation and haemodialysis. This observation is biologically plausible due to the recognised importance of coenzyme Q10 in mitochondrial bioenergetics within myocytes, and the fact that statins inhibit farnesyl pyrophosphate production, a biochemical step crucial for coenzyme Q10 synthesis. Coenzyme Q10 is generally well tolerated, and may potentially benefit patients with statin-induced rhabdomyolysis.

  15. HMG-CoA reductase inhibitor rosuvastatin improves abnormal brain electrical activity via mechanisms involving eNOS.

    PubMed

    Seker, F B; Kilic, U; Caglayan, B; Ethemoglu, M S; Caglayan, A B; Ekimci, N; Demirci, S; Dogan, A; Oztezcan, S; Sahin, F; Yilmaz, B; Kilic, E

    2015-01-22

    Apart from its repressing effect on plasma lipid levels, 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors exert neuroprotective functions in animal models of neurodegenerative disorders. In view of these promising observations, we were interested in whether HMG-CoA reductase inhibition would affect epileptiform activity in the brain. To elucidate this issue, atorvastatin, simvastatin and rosuvastatin were administered orally at a dose of 20 mg/kg each for 3 days and their anti-epileptic activities were tested and compared in rats. Epileptiform activity in the brain was induced by an intracortical penicillin G injection. Among HMG-CoA reductase inhibitors, simvastatin-treatment was less effective in terms of spike frequency as compared with atorvastatin- and rosuvastatin-treated animals. Atorvastatin treatment reduced spike frequencies and amplitudes significantly throughout the experiment. However, the most pronounced anti-epileptic effect was observed in rosuvastatin-treated animals, which was associated with improved blood-brain barrier (BBB) integrity, increased expression of endothelial nitric oxide synthase (eNOS) mRNA and decreased expressions of pro-apoptotic p53, Bax and caspase-3 mRNAs. Inhibition of eNOS activity with L-NG-Nitroarginine Methyl Ester (L-NAME) reversed the anti-epileptic effect of rosuvastatin significantly. However, L-NAME did not alter the effect of rosuvastatin on the levels of p53, Bax and caspase-3 mRNA expression. Here, we provide evidence that among HMG-CoA reductase inhibitors, rosuvastatin was the most effective statin on the reduction of epileptiform activity, which was associated with improved BBB permeability, increased expression of eNOS and decreased expressions of pro-apoptotic p53, Bax and caspase-3. Our observation also revealed that the anti-epileptic effect of rosuvastatin was dependent on the increased expression level of eNOS. The robust anti-epileptic effect encourages proof-of-concept studies with

  16. Rosuvastatin as a potential preventive drug for the development of hepatocellular carcinoma associated with non-alcoholic fatty liver disease in mice.

    PubMed

    Yokohama, Keisuke; Fukunishi, Shinya; Ii, Masaaki; Nakamura, Ken; Ohama, Hideko; Tsuchimoto, Yusuke; Asai, Akira; Tsuda, Yasuhiro; Higuchi, Kazuhide

    2016-11-01

    Hepatocellular carcinoma (HCC) represents approximately 85% of all primary liver cancer cases. Non-alcoholic fatty liver disease (NAFLD) is one of the risk factors for HCC. NAFLD occurs in patients with components of metabolic syndrome, such as type 2 diabetes mellitus, obesity, hypertension and hyperlipidemia. Therefore, hyperlipidemia also represents a patient population at risk for HCC that can readily be identified. Rosuvastatin, a 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitor, has exhibited a more potent affinity for the active site of HMG-CoA reductase than other statins. In addition, the hepatic uptake of rosuvastatin in rats has been found to be more selective and efficient than that with other drugs. Furthermore, the cytoprotective effects of rosuvastatin against ischemic injury have been clearly reported. Thus, in this study, we aimed to determine the role of rosuvastatin as a preventive drug in HCC associated with NAFLD. STAM mice, which developed HCC from NAFLD by being fed a high-fat diet (HFD), were divided into a group in which a HFD was given to the mice for 15 weeks (n=8) and another in which a HFD supplemented with 0.00125% rosuvastatin was given to the mice for 15 weeks (n=8). Rosuvastatin inhibited the development of hepatic tumors in the mice with NAFLD induced by a specific diet both macroscopically and histologically. Rosuvastatin significantly decreased the expression levels of pro-inflammatry cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-6 and transforming growth factor (TGF)-β1. Tumor aggressiveness is mediated by angiogenic factors. Therefore, we examined the hepatic mRNA expression of vascular endothelial growth factor receptor (VEGFR), epidermal growth factor receptor (EGFR) and platelet-derived growth factor (PDGF). The hepatic expression of these factors significantly decreased in the rousvastin-fed mice. Our results thus suggest rosuvastatin that prevents carcinogenesis

  17. Mevinolin (lovastatin) potentiates the antiproliferative effects of ketoconazole and terbinafine against Trypanosoma (Schizotrypanum) cruzi: in vitro and in vivo studies.

    PubMed Central

    Urbina, J A; Lazardi, K; Marchan, E; Visbal, G; Aguirre, T; Piras, M M; Piras, R; Maldonado, R A; Payares, G; de Souza, W

    1993-01-01

    We have studied the antiproliferative effects of mevinolin (lovastatin), an inhibitor of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, on the protozoan parasite Trypanosoma (Schizotrypanum) cruzi and its ability to potentiate the action of specific ergosterol biosynthesis inhibitors, such as ketoconazole and terbinafine, both in vitro and in vivo. Against the epimastigote form in vitro, mevinolin produced a dose-dependent reduction of the growth rate up to 25 microM, but at 50 and 75 microM, complete growth arrest and cell lysis took place after 144 and 96 h, respectively. A systematic study of the effects of mevinolin combined with ketoconazole and terbinafine, which act at different points in the ergosterol biosynthesis pathway, on the proliferation of epimastigotes indicated a synergic action, as shown by concave isobolograms and fractional inhibitory concentration indexes ranging from 0.17 to 0.54. Analysis of the sterol composition and de novo sterol synthesis in control and treated cells by thin-layer and gas-liquid chromatographies showed that the antiproliferative effects of the drug alone and in combination were correlated with the depletion of the endogenous ergosterol pool and particularly with a critical (exogenous) cholesterol/endogenous 4-desmethyl sterol ratio in the cells. When we studied the effects of mevinolin on the amastigote form proliferating inside Vero cells in vitro, only very modest effects on the parasites were observed up to 0.75 microM; above this concentration, significant deleterious effects on the host cells were found. However, when the same concentration of the drug was combined with ketoconazole, it was able to reduce by a factor of 10 the concentration of the azole required to eradicate the parasite (from 10 to 1 nM), again indicating a synergic action. On the other hand, a combination of mevinolin and terbinafine had only additive effects on amastigotes, but a ternary combination of mevinolin, ketoconazole, and terbinafine

  18. Relative expression of genes of terpene metabolism in different tissues of Artemisia annua L

    PubMed Central

    2011-01-01

    Background Recently, Artemisia annua L. (annual or sweet wormwood) has received increasing attention due to the fact that the plant produces the sesquiterpenoid endoperoxide artemisinin, which today is widely used for treatment of malaria. The plant produces relatively small amounts of artemisinin and a worldwide shortage of the drug has led to intense research in order to increase the yield of artemisinin. In order to improve our understanding of terpene metabolism in the plant and to evaluate the competition for precursors, which may influence the yield of artemisinin, we have used qPCR to estimate the expression of 14 genes of terpene metabolism in different tissues. Results The four genes of the artemisinin biosynthetic pathway (amorpha-4,11-diene synthase, amorphadiene-12-hydroxylase, artemisinic aldehyde ∆11(13) reductase and aldehyde dehydrogenase 1) showed remarkably higher expression (between ~40- to ~500-fold) in flower buds and young leaves compared to other tissues (old leaves, stems, roots, hairy root cultures). Further, dihydroartemisinic aldehyde reductase showed a very high expression only in hairy root cultures. Germacrene A and caryophyllene synthase were mostly expressed in young leaves and flower buds while epi-cedrol synthase was highly expressed in old leaves. 3-Hydroxy-3-methyl-glutaryl coenzyme A reductase exhibited lower expression in old leaves compared to other tissues. Farnesyldiphosphate synthase, squalene synthase, and 1-deoxy-D-xylulose-5-phosphate reductoisomerase showed only modest variation in expression in the different tissues, while expression of 1-deoxy-D-xylulose-5-phosphate synthase was 7-8-fold higher in flower buds and young leaves compared to old leaves. Conclusions Four genes of artemisinin biosynthesis were highly expressed in flower buds and young leaves (tissues showing a high density of glandular trichomes). The expression of dihydroartemisinic aldehyde reductase has been suggested to have a negative effect on

  19. Acute Simvastatin Inhibits KATP Channels of Porcine Coronary Artery Myocytes

    PubMed Central

    Zhang, Qian; Li, Rachel Wai Sum; Kong, Siu Kai; Ngai, Sai Ming; Wan, Song; Ho, Ho Pui; Lee, Simon Ming Yuen; Hoi, Maggie Pui Man; Chan, Shun Wan; Leung, George Pak Heng; Kwan, Yiu Wa

    2013-01-01

    Background Statins (3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors) consumption provides beneficial effects on cardiovascular systems. However, effects of statins on vascular KATP channel gatings are unknown. Methods Pig left anterior descending coronary artery and human left internal mammary artery were isolated and endothelium-denuded for tension measurements and Western immunoblots. Enzymatically-dissociated/cultured arterial myocytes were used for patch-clamp electrophysiological studies and for [Ca2+]i, [ATP]i and [glucose]o uptake measurements. Results The cromakalim (10 nM to 10 µM)- and pinacidil (10 nM to 10 µM)-induced concentration-dependent relaxation of porcine coronary artery was inhibited by simvastatin (3 and 10 µM). Simvastatin (1, 3 and 10 µM) suppressed (in okadaic acid (10 nM)-sensitive manner) cromakalim (10 µM)- and pinacidil (10 µM)-mediated opening of whole-cell KATP channels of arterial myocytes. Simvastatin (10 µM) and AICAR (1 mM) elicited a time-dependent, compound C (1 µM)-sensitive [3H]-2-deoxy-glucose uptake and an increase in [ATP]i levels. A time (2–30 min)- and concentration (0.1–10 µM)-dependent increase by simvastatin of p-AMPKα-Thr172 and p-PP2A-Tyr307 expression was observed. The enhanced p-AMPKα-Thr172 expression was inhibited by compound C, ryanodine (100 µM) and KN93 (10 µM). Simvastatin-induced p-PP2A-Tyr307 expression was suppressed by okadaic acid, compound C, ryanodine, KN93, phloridzin (1 mM), ouabain (10 µM), and in [glucose]o-free or [Na+]o-free conditions. Conclusions Simvastatin causes ryanodine-sensitive Ca2+ release which is important for AMPKα-Thr172 phosphorylation via Ca2+/CaMK II. AMPKα-Thr172 phosphorylation causes [glucose]o uptake (and an [ATP]i increase), closure of KATP channels, and phosphorylation of AMPKα-Thr172 and PP2A-Tyr307 resulted. Phosphorylation of PP2A-Tyr307 occurs at a site downstream of AMPKα-Thr172 phosphorylation. PMID:23799098

  20. Co-Administration of Cholesterol-Lowering Probiotics and Anthraquinone from Cassia obtusifolia L. Ameliorate Non-Alcoholic Fatty Liver.

    PubMed

    Mei, Lu; Tang, Youcai; Li, Ming; Yang, Pingchang; Liu, Zhiqiang; Yuan, Jieli; Zheng, Pengyuan

    2015-01-01

    Non-alcoholic fatty liver disease (NAFLD) has become a common liver disease in recent decades. No effective treatment is currently available. Probiotics and natural functional food may be promising therapeutic approaches to this disease. The present study aims to investigate the efficiency of the anthraquinone from Cassia obtusifolia L. (AC) together with cholesterol-lowering probiotics (P) to improve high-fat diet (HFD)-induced NAFLD in rat models and elucidate the underlying mechanism. Cholesterol-lowering probiotics were screened out by MRS-cholesterol broth with ammonium ferric sulfate method. Male Sprague-Dawley rats were fed with HFD and subsequently administered with AC and/or P. Lipid metabolism parameters and fat synthesis related genes in rat liver, as well as the diversity of gut microbiota were evaluated. The results demonstrated that, compared with the NAFLD rat, the serum lipid levels of treated rats were reduced effectively. Besides, cholesterol 7α-hydroxylase (CYP7A1), low density lipoprotein receptor (LDL-R) and farnesoid X receptor (FXR) were up-regulated while the expression of 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMGCR) was reduced. The expression of peroxisome proliferator activated receptor (PPAR)-α protein was significantly increased while the expression of PPAR-γ and sterol regulatory element binding protein-1c (SREBP-1c) was down-regulated. In addition, compared with HFD group, in AC, P and AC+P group, the expression of intestinal tight-junction protein occludin and zonula occluden-1 (ZO-1) were up-regulated. Furthermore, altered gut microbiota diversity after the treatment of probiotics and AC were analysed. The combination of cholesterol-lowering probiotics and AC possesses a therapeutic effect on NAFLD in rats by up-regulating CYP7A1, LDL-R, FXR mRNA and PPAR-α protein produced in the process of fat metabolism while down-regulating the expression of HMGCR, PPAR-γ and SREBP-1c, and through normalizing the intestinal

  1. Residues that influence coenzyme preference in the aldehyde dehydrogenases.

    PubMed

    González-Segura, Lilian; Riveros-Rosas, Héctor; Julián-Sánchez, Adriana; Muñoz-Clares, Rosario A

    2015-06-05

    To find out the residues that influence the coenzyme preference of aldehyde dehydrogenases (ALDHs), we reviewed, analyzed and correlated data from their known crystal structures and amino-acid sequences with their published kinetic parameters for NAD(P)(+). We found that the conformation of the Rossmann-fold loops participating in binding the adenosine ribose is very conserved among ALDHs, so that coenzyme specificity is mainly determined by the nature of the residue at position 195 (human ALDH2 numbering). Enzymes with glutamate or proline at 195 prefer NAD(+) because the side-chains of these residues electrostatically and/or sterically repel the 2'-phosphate group of NADP(+). But contrary to the conformational rigidity of proline, the conformational flexibility of glutamate may allow NADP(+)-binding in some enzymes by moving the carboxyl group away from the 2'-phosphate group, which is possible if a small neutral residue is located at position 224, and favored if the residue at position 53 interacts with Glu195 in a NADP(+)-compatible conformation. Of the residues found at position 195, only glutamate interacts with the NAD(+)-adenosine ribose; glutamine and histidine cannot since their side-chain points are opposite to the ribose, probably because the absence of the electrostatic attraction by the conserved nearby Lys192, or its electrostatic repulsion, respectively. The shorter side-chains of other residues-aspartate, serine, threonine, alanine, valine, leucine, or isoleucine-are distant from the ribose but leave room for binding the 2'-phosphate group. Generally, enzymes having a residue different from Glu bind NAD(+) with less affinity, but they can also bind NADP(+) even sometimes with higher affinity than NAD(+), as do enzymes containing Thr/Ser/Gln195. Coenzyme preference is a variable feature within many ALDH families, consistent with being mainly dependent on a single residue that apparently has no other structural or functional roles, and therefore can

  2. Glutamate dehydrogenases: the why and how of coenzyme specificity.

    PubMed

    Engel, Paul C

    2014-01-01

    NAD(+) and NADP(+), chemically similar and with almost identical standard oxidation-reduction potentials, nevertheless have distinct roles, NAD(+) serving catabolism and ATP generation whereas NADPH is the biosynthetic reductant. Separating these roles requires strict specificity for one or the other coenzyme for most dehydrogenases. In many organisms this holds also for glutamate dehydrogenases (GDH), NAD(+)-dependent for glutamate oxidation, NADP(+)-dependent for fixing ammonia. In higher animals, however, GDH has dual specificity. It has been suggested that GDH in mitochondria reacts only with NADP(H), the NAD(+) reaction being an in vitro artefact. However, contrary evidence suggests mitochondrial GDH not only reacts with NAD(+) but maintains equilibrium using the same pool as accessed by β-hydroxybutyrate dehydrogenase. Another complication is the presence of an energy-linked dehydrogenase driving NADP(+) reduction by NADH, maintaining the coenzyme pools at different oxidation-reduction potentials. Its coexistence with GDH makes possible a futile cycle, control of which is not yet properly explained. Structural studies show NAD(+)-dependent, NADP(+)-dependent and dual-specificity GDHs are closely related and a few site-directed mutations can reverse specificity. Specificity for NAD(+) or for NADP(+) has probably emerged repeatedly during evolution, using different structural solutions on different occasions. In various GDHs the P7 position in the coenzyme-binding domain plays a key role. However, whereas in other dehydrogenases an acidic P7 residue usually hydrogen bonds to the 2'- and 3'-hydroxyls, dictating NAD(+) specificity, among GDHs, depending on detailed conformation of surrounding residues, an acidic P7 may permit binding of NAD(+) only, NADP(+) only, or in higher animals both.

  3. Coenzyme Q10 counteracts testicular injury induced by sodium arsenite in rats.

    PubMed

    Fouad, Amr A; Al-Sultan, Ali Ibrahim; Yacoubi, Mohamed T

    2011-03-25

    The protective effect of coenzyme Q10 against testicular toxicity induced by sodium arsenite (10mg/kg/day, orally for two consecutive days) was investigated in rats. Coenzyme Q10 treatment (10mg/kg/day, i.p.) was applied for five consecutive days, starting three days before arsenite administration. Coenzyme Q10 significantly increased serum testosterone level which was reduced by sodium arsenite. Coenzyme Q10 significantly suppressed lipid peroxidation, restored the depleted antioxidant defenses, and attenuated the increases of tumor necrosis factor-α and nitric oxide resulted from arsenic administration. Also, the elevation of arsenic ion, and the reductions of selenium and zinc ions in testicular tissue were mitigated by coenzyme Q10. Histopathological examination showed that testicular injury mediated by arsenic was ameliorated by coenzyme Q10 treatment. Immunohistochemical analysis revealed that coenzyme Q10 significantly decreased the arsenic-induced expression of inducible nitric oxide synthase, nuclear factor-κB, Fas ligand and caspase-3 in testicular tissue. It was concluded that coenzyme Q10 represents a potential therapeutic option to protect the testicular tissue from the detrimental effects of arsenic intoxication.

  4. Coenzyme Q10 prevents high glucose-induced oxidative stress in human umbilical vein endothelial cells.

    PubMed

    Tsuneki, Hiroshi; Sekizaki, Naoto; Suzuki, Takashi; Kobayashi, Shinjiro; Wada, Tsutomu; Okamoto, Tadashi; Kimura, Ikuko; Sasaoka, Toshiyasu

    2007-07-02

    Hyperglycemia-induced oxidative stress plays a crucial role in the pathogenesis of vascular complications in diabetes. Although some clinical evidences suggest the use of an antioxidant reagent coenzyme Q10 in diabetes with hypertension, the direct effect of coenzyme Q10 on the endothelial functions has not been examined. In the present study, we therefore investigated the protective effect of coenzyme Q10 against high glucose-induced oxidative stress in human umbilical vein endothelial cells (HUVEC). HUVEC exposed to high glucose (30 mM) exhibited abnormal properties, including the morphological and biochemical features of apoptosis, overproduction of reactive oxygen species, activation of protein kinase Cbeta2, and increase in endothelial nitric oxide synthase expression. Treatment with coenzyme Q10 strongly inhibited these changes in HUVEC under high glucose condition. In addition, coenzyme Q10 inhibited high glucose-induced cleavage of poly(ADP-ribose) polymerase, an endogenous caspase-3 substrate. These results suggest that coenzyme Q10 prevents reactive oxygen species-induced apoptosis through inhibition of the mitochondria-dependent caspase-3 pathway. Moreover, consistent with previous reports, high glucose caused upregulation of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in HUVEC, and promoted the adhesion of U937 monocytic cells. Coenzyme Q10 displayed potent inhibitory effects against these endothelial abnormalities. Thus, we provide the first evidence that coenzyme Q10 has a beneficial effect in protecting against the endothelial dysfunction by high glucose-induced oxidative stress in vitro.

  5. Crystal structure of methyl-coenzyme M reductase: the key enzyme of biological methane formation.

    PubMed

    Ermler, U; Grabarse, W; Shima, S; Goubeaud, M; Thauer, R K

    1997-11-21

    Methyl-coenzyme M reductase (MCR), the enzyme responsible for the microbial formation of methane, is a 300-kilodalton protein organized as a hexamer in an alpha2beta2gamma2 arrangement. The crystal structure of the enzyme from Methanobacterium thermoautotrophicum, determined at 1.45 angstrom resolution for the inactive enzyme state MCRox1-silent, reveals that two molecules of the nickel porphinoid coenzyme F430 are embedded between the subunits alpha, alpha', beta, and gamma and alpha', alpha, beta', and gamma', forming two identical active sites. Each site is accessible for the substrate methyl-coenzyme M through a narrow channel locked after binding of the second substrate coenzyme B. Together with a second structurally characterized enzyme state (MCRsilent) containing the heterodisulfide of coenzymes M and B, a reaction mechanism is proposed that uses a radical intermediate and a nickel organic compound.

  6. 76 FR 42729 - Certain Coenzyme Q10 Products and Methods of Making Same; Notice of Institution of Investigation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-19

    ... COMMISSION Certain Coenzyme Q10 Products and Methods of Making Same; Notice of Institution of Investigation... importation, and the sale within the United States after importation of certain coenzyme Q10 products and... importation, or the sale within the United States after importation of certain coenzyme Q10 products...

  7. Excited flavin and pterin coenzyme molecules in evolution.

    PubMed

    Kritsky, M S; Telegina, T A; Vechtomova, Y L; Kolesnikov, M P; Lyudnikova, T A; Golub, O A

    2010-10-01

    Excited flavin and pterin molecules are active in intermolecular energy transfer and in photocatalysis of redox reactions resulting in conservation of free energy. Flavin-containing pigments produced in models of the prebiotic environment are capable of converting photon energy into the energy of phosphoanhydride bonds of ATP. However, during evolution photochemical reactions involving excited FMN or FAD molecules failed to become participants of bioenergy transfer systems, but they appear in enzymes responsible for repair of UV-damaged DNA (DNA photolyases) and also in receptors of blue and UV-A light regulating vital functions of organisms. The families of these photoproteins (DNA-photolyases and cryptochromes, LOV-domain- and BLUF-domain-containing proteins) are different in the structure and in mechanisms of the photoprocesses. The excited flavin molecules are involved in photochemical processes in reaction centers of these photoproteins. In DNA photolyases and cryptochromes the excitation energy on the reaction center flavin is supplied from an antenna molecule that is bound with the same polypeptide. The role of antenna is played by MTHF or by 8-HDF in some DNA photolyases, i.e. also by molecules with known coenzyme functions in biocatalysis. Differences in the structure of chromophore-binding domains suggest an independent origin of the photoprotein families. The analysis of structure and properties of coenzyme molecules reveals some specific features that were significant in evolution for their being selected as chromophores in these proteins.

  8. Molecular Insights into the Biosynthesis of the F420 Coenzyme

    SciTech Connect

    Forouhar,F.; Abashidze, M.; Xu, H.; Grochowski, L.; Seetharaman, J.; Hussain, M.; Kuzin, A.; Chen, Y.; Zhou, W.; et al

    2008-01-01

    Coenzyme F420, a hydride carrier, is found in Archaea and some bacteria and has crucial roles in methanogenesis, antibiotic biosynthesis, DNA repair, and activation of antitubercular compounds. CofD, 2-phospho-l-lactate transferase, catalyzes the last step in the biosynthesis of F420-0 (F420 without polyglutamate), by transferring the lactyl phosphate moiety of lactyl(2)diphospho-(5')guanosine to 7,8-didemethyl-8-hydroxy-5-deazariboflavin ribitol (Fo). CofD is highly conserved among F420-producing organisms, and weak sequence homologs are also found in non-F420-producing organisms. This superfamily does not share any recognizable sequence conservation with other proteins. Here we report the first crystal structures of CofD, the free enzyme and two ternary complexes, with Fo and Pi or with Fo and GDP, from Methanosarcina mazei. The active site is located at the C-terminal end of a Rossmann fold core, and three large insertions make significant contributions to the active site and dimer formation. The observed binding modes of Fo and GDP can explain known biochemical properties of CofD and are also supported by our binding assays. The structures provide significant molecular insights into the biosynthesis of the F420 coenzyme. Large structural differences in the active site region of the non-F420-producing CofD homologs suggest that they catalyze a different biochemical reaction.

  9. Coenzyme-like ligands for affinity isolation of cholesterol oxidase.

    PubMed

    Xin, Yu; Lu, Liushen; Wang, Qing; Zhang, Ling; Tong, Yanjun; Wang, Wu

    2016-05-15

    Two coenzyme-like chemical ligands were designed and synthesized for affinity isolation of cholesterol oxidase (COD). To simulate the structure of natural coenzyme of COD (flavin adenine dinucleotide (FAD)), on Sepharose beads, 5-aminouracil, cyanuric chloride and 1, 4-butanediamine were composed and then modified. The COD gene from Brevibacterium sp. (DQ345780) was expressed in Escherichia coli BL21 (DE3), and then the sorbents were applied to adsorption analysis with the pure enzyme. Subsequently, the captured enzyme was applied to SDS-PAGE and activity analysis. As calculated, the theoretical maximum adsorption (Qmax) of the two affinity sorbents (RL-1 and RL-2) were ∼83.5 and 46.3mg/g wet gel; and the desorption constant Kd of the two sorbents were ∼6.02×10(-4) and 1.19×10(-4)μM. The proteins after cell lysis were applied to affinity isolation, and then after one step of affinity binding on the two sorbents, the protein recoveries of RL-1 and RL-2 were 9.2% and 9.7%; the bioactivity recoveries were 92.7% and 91.3%, respectively. SDS-PAGE analysis revealed that the purities of COD isolated with the two affinity sorbents were approximately 95%.

  10. Coenzyme Q-10 in Human Health: Supporting Evidence?

    PubMed

    Saha, Sibu P; Whayne, Thomas F

    2016-01-01

    Coenzyme Q-10 (CoQ10) is a widely used alternative medication or dietary supplement and one of its roles is as an antioxidant. It naturally functions as a coenzyme and component of oxidative phosphorylation in mitochondria. Decreased levels have been demonstrated in diseased myocardium and in Parkinson disease. Farnesyl pyrophosphate is a critical intermediate for CoQ10 synthesis and blockage of this step may be important in statin myopathy. Deficiency of CoQ10 also has been associated with encephalomyopathy, severe infantile multisystemic disease, cerebellar ataxia, nephrotic syndrome, and isolated myopathy. Although supplementation with CoQ10 has been reported to be beneficial in treating hypertension, congestive heart failure, statin myopathy, and problems associated with chemotherapy for cancer treatement, this use of CoQ10 as a supplement has not been confirmed in randomized controlled clinical trials. Nevertheless, it appears to be a safe supplementary medication where usage in selected clinical situations may not be inappropriate. This review is an attempt to actualize the available information on CoQ10 and define its potential benefit and appropriate usage.

  11. Mechanistic implications from structures of yeast alcohol dehydrogenase complexed with coenzyme and an alcohol.

    PubMed

    Plapp, Bryce V; Charlier, Henry A; Ramaswamy, S

    2016-02-01

    Yeast alcohol dehydrogenase I is a homotetramer of subunits with 347 amino acid residues, catalyzing the oxidation of alcohols using NAD(+) as coenzyme. A new X-ray structure was determined at 3.0 Å where both subunits of an asymmetric dimer bind coenzyme and trifluoroethanol. The tetramer is a pair of back-to-back dimers. Subunit A has a closed conformation and can represent a Michaelis complex with an appropriate geometry for hydride transfer between coenzyme and alcohol, with the oxygen of 2,2,2-trifluoroethanol ligated at 2.1 Å to the catalytic zinc in the classical tetrahedral coordination with Cys-43, Cys-153, and His-66. Subunit B has an open conformation, and the coenzyme interacts with amino acid residues from the coenzyme binding domain, but not with residues from the catalytic domain. Coenzyme appears to bind to and dissociate from the open conformation. The catalytic zinc in subunit B has an alternative, inverted coordination with Cys-43, Cys-153, His-66 and the carboxylate of Glu-67, while the oxygen of trifluoroethanol is 3.5 Å from the zinc. Subunit B may represent an intermediate in the mechanism after coenzyme and alcohol bind and before the conformation changes to the closed form and the alcohol oxygen binds to the zinc and displaces Glu-67.

  12. Effect of coenzyme q10 on myopathic symptoms in patients treated with statins.

    PubMed

    Caso, Giuseppe; Kelly, Patricia; McNurlan, Margaret A; Lawson, William E

    2007-05-15

    Treatment of hypercholesterolemia with statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) is effective in the primary and secondary prevention of cardiovascular disease. However, statin use is often associated with a variety of muscle-related symptoms or myopathies. Myopathy may be related in part to statin inhibition of the endogenous synthesis of coenzyme Q10, an essential cofactor for mitochondrial energy production. The aim of this study is to determine whether coenzyme Q10 supplementation would reduce the degree of muscle pain associated with statin treatment. Patients with myopathic symptoms were randomly assigned in a double-blinded protocol to treatment with coenzyme Q10 (100 mg/day, n = 18) or vitamin E (400 IU/day, n = 14) for 30 days. Muscle pain and pain interference with daily activities were assessed before and after treatment. After a 30-day intervention, pain severity decreased by 40% (p <0.001) and pain interference with daily activities decreased by 38% (p <0.02) in the group treated with coenzyme Q10. In contrast, no changes in pain severity (+9%, p = NS) or pain interference with daily activities (-11%, p = NS) was observed in the group treated with vitamin E. In conclusion, results suggest that coenzyme Q10 supplementation may decrease muscle pain associated with statin treatment. Thus, coenzyme Q10 supplementation may offer an alternative to stopping treatment with these vital drugs.

  13. Preparation and physicochemical characterization of aqueous dispersions of coenzyme Q10 nanoparticles.

    PubMed

    Siekmann, B; Westesen, K

    1995-02-01

    The present study describes a novel pharmaceutical formulation of coenzyme Q10, viz. submicron-sized dispersions of the substance prepared by emulsification of molten coenzyme Q10 in an aqueous phase. Photon correlation spectroscopy reveals mean diameters of 60 to 300 nm depending on process parameters. Coenzyme Q10 nanoparticles remain stable on storage for more than 30 months. Lipophilic drugs can be incorporated into the nanoparticles demonstrating their potential use as a drug carrier system. Transmission electron micrographs of freeze-fractured replica show spherical particles with an amorphous core. Cryo-electron microscopy reveals the coexistence of small unilamellar vesicles in phospholipid stabilized dispersions. Thermoanalysis and X-ray studies indicate that the dispersed and emulsified coenzyme Q10 does not recrystallize even at 4 degrees C over 30 months. These agree with 1H NMR data which demonstrate that coenzyme Q10 molecules have a high mobility when formulated as nanoparticles and that colloidally dispersed coenzyme Q10 remains in the state of a supercooled melt. Despite the high melting point of the bulk material, coenzyme Q10 dispersions represent no suspensions but O/W emulsions according to the IUPAC definition (1).

  14. Alteration of coenzyme specificity of malate dehydrogenase from Streptomyces coelicolor A3(2) by site-directed mutagenesis.

    PubMed

    Ge, Y D; Song, P; Cao, Z Y; Wang, P; Zhu, G P

    2014-07-29

    We describe here for the first time the alteration of coenzyme specificity of malate dehydrogenase (MDH) from Streptomyces coelicolor A3(2) (ScMDH). In the present study, we replaced four amino acid residues in the Rossmann fold (βB-αC) region of NADH-dependent ScMDH by site-directed mutagenesis with those of NADPH-dependent MDH (Glu42Gly, Ile43Ser, Pro45Arg, and Ala46Ser). The coenzyme specificity of the mutant enzyme (ScMDH-T4) was examined. Coenzyme specificity of ScMDH-T4 was shifted 2231.3-fold toward NADPH using kcat/Km(coenzyme) as the measurement of coenzyme specificity. Accordingly, the effect of the replacements on coenzyme specificity is discussed. Our work provides further insight into the coenzyme specificity of ScMDH.

  15. Coenzyme Q10 - A new player in the treatment of heart failure?

    PubMed

    Jankowski, Jerzy; Korzeniowska, Katarzyna; Cieślewicz, Artur; Jabłecka, Anna

    2016-10-01

    Coenzyme Q10 is the only endogenously synthesized lipid with a redox function which exhibits broad tissue and intracellular distribution in mammals. Beneficial effects of Coenzyme Q10 supplementation were observed in several age-related diseases including heart failure. CoQ10 (coenzyme Q10) level is significantly decreased in patients with this disease, which correlates with severity of clinical symptoms. Supplementation with various pharmaceutical formulations of CoQ10 improves impaired cardiac function and clinical course of heart failure. Current data from clinical trials indicate that CoQ10 can significantly reduce morbidity and mortality of heart failure patients in addition to guideline recommended pharmacotherapy.

  16. Control of redox reactivity of flavin and pterin coenzymes by metal ion coordination and hydrogen bonding.

    PubMed

    Fukuzumi, Shunichi; Kojima, Takahiko

    2008-03-01

    The electron-transfer activities of flavin and pterin coenzymes can be fine-tuned by coordination of metal ions, protonation and hydrogen bonding. Formation of hydrogen bonds with a hydrogen-bond receptor in metal-flavin complexes is made possible depending on the type of coordination bond that can leave the hydrogen-bonding sites. The electron-transfer catalytic functions of flavin and pterin coenzymes are described by showing a number of examples of both thermal and photochemical redox reactions, which proceed by controlling the electron-transfer reactivity of coenzymes with metal ion binding, protonation and hydrogen bonding.

  17. Beneficial effect of coenzyme Q10 injection on nitric oxide -related dilation of the rat aorta.

    PubMed

    Kozaeva, Larisa P; Gorodetskaya, Evgeniya A; Ruuge, Enno K; Kalenikova, Elena I; Medvedev, Oleg S

    2017-01-05

    This study examined whether coenzyme Q10 can improve nitric oxide (NO)-dependent vasodilatation in the rat aorta after pre-incubation or intravenous administration. In initial experiments, intact isolated aortic rings were incubated with coenzyme Q10 or L-arginine. In further experiments, coenzyme Q10 was administered intravenously in anesthetized rats, then in 2h aorta was isolated. In both cases, after preliminary preparation the isolated aortic rings were tested for acetylcholine-induced NO-dependent relaxation. Acetylcholine elicited concentration-dependent relaxation of phenylephine precontracted aortic rings. Relaxant responses to acetylcholine were markedly potentiated after pre-incubation with coenzyme Q10 or L-arginine. The maximum relaxant responses (%) were significantly increased from 64.1±5.3 (control) to 89.8±3.0 and 83.6±3.0 (coenzyme Q10 and L-arginine, respectively). pD2 (-lgEC50) value in control study was 5.81±0.28, after pretreatment with coenzyme Q10 or L-arginine were 7.59±0.16 and 7.26±0.32, respectively. There was no difference between coenzyme Q10 and L-arginine groups. After intravenous administration, the relaxant responses to acetylcholine were significantly increased in coenzyme Q10-treated group (94.2±2.0) compared with controls (68.1±4.4). pD2 values were also different between control and treatment groups (5.79±0.29 vs. 8.14±0.65, respectively). Thus, coenzyme Q10 improved NO-mediated vasodilation in rat aorta in magnitude close to the effects of L-arginine - substrate for eNOS. Our data first show that exogenous coenzyme Q10 through intravenous administration is able to improve rapidly NO-dependent vasodilation in rat aorta, likely due to accumulation of coenzyme Q10 in the vessel wall. Improvement of endothelial function can contribute, at least in part, to beneficial effects of coenzyme Q10 in cardiovascular diseases associated with endothelial dysfunction.

  18. Pyridine nucleotide coenzymes: Chemical, biological, and medical aspects. Vol. 2, Pt. A

    SciTech Connect

    Dolphin, D.; Poulson, R.; Avramovic, O.

    1987-01-01

    This text contains the following: History of the Pyridine Nucleotides Nomenclature; Evolution of Pyridine Nucleotide; Relationship Between Biosynthesis and Evolution; Crystal Structure; Coenzyme Conformations; Protein Interactions; Optical Spectroscopy of the Pyridine Nucleotides; Excited States of Pyridine Nucleotide Coenzymes; Fluorescence and Phosphorescence; Nuclear Magnetic Resonance Spectroscopy of Pyridine Nucleotides; Mass Spectrometry of Pyridine Nucleotides; Mechanism of Action of the Pyridine Nucleotides; Chemical Stability and Reactivity of Pyridine Nucleotide Coenzymes; Stereochemistry of Fatty Acid Biosynthesis and Metabolism; Kinetics of Pyridine Nucleotide-Utilizing Enzymes; Preparation and Properties of NAD and NADP Analogs; Model Studies and Biological Activity of Analogs; and Spin-Labeled Pyridine Nucleotide Derivatives.

  19. Bioenergetic and antioxidant properties of coenzyme Q10: recent developments.

    PubMed

    Littarru, Gian Paolo; Tiano, Luca

    2007-09-01

    For a number of years, coenzyme Q (CoQ10 in humans) was known for its key role in mitochondrial bioenergetics; later studies demonstrated its presence in other subcellular fractions and in plasma, and extensively investigated its antioxidant role. These two functions constitute the basis on which research supporting the clinical use of CoQ10 is founded. Also at the inner mitochondrial membrane level, coenzyme Q is recognized as an obligatory co-factor for the function of uncoupling proteins and a modulator of the transition pore. Furthermore, recent data reveal that CoQ10 affects expression of genes involved in human cell signalling, metabolism, and transport and some of the effects of exogenously administered CoQ10 may be due to this property. Coenzyme Q is the only lipid soluble antioxidant synthesized endogenously. In its reduced form, CoQH2, ubiquinol, inhibits protein and DNA oxidation but it is the effect on lipid peroxidation that has been most deeply studied. Ubiquinol inhibits the peroxidation of cell membrane lipids and also that of lipoprotein lipids present in the circulation. Dietary supplementation with CoQ10 results in increased levels of ubiquinol-10 within circulating lipoproteins and increased resistance of human low-density lipoproteins to the initiation of lipid peroxidation. Moreover, CoQ10 has a direct anti-atherogenic effect, which has been demonstrated in apolipoprotein E-deficient mice fed with a high-fat diet. In this model, supplementation with CoQ10 at pharmacological doses was capable of decreasing the absolute concentration of lipid hydroperoxides in atherosclerotic lesions and of minimizing the size of atherosclerotic lesions in the whole aorta. Whether these protective effects are only due to the antioxidant properties of coenzyme Q remains to be established; recent data point out that CoQ10 could have a direct effect on endothelial function. In patients with stable moderate CHF, oral CoQ10 supplementation was shown to ameliorate

  20. Current state of coenzyme Q(10) production and its applications.

    PubMed

    Jeya, Marimuthu; Moon, Hee-Jung; Lee, Jeong-Lim; Kim, In-Won; Lee, Jung-Kul

    2010-02-01

    Coenzyme Q(10) (CoQ(10)), an obligatory cofactor in the aerobic respiratory electron transfer for energy generation, is formed from the conjugation of a benzoquinone ring with a hydrophobic isoprenoid chain. CoQ(10) is now used as a nutritional supplement because of its antioxidant properties and is beneficial in the treatment of several human diseases when administered orally. Bioprocesses have been developed for the commercial production of CoQ(10) because of its increased demand, and these bioprocesses depend on microbes that produce high levels of CoQ(10) naturally. However, as knowledge of the biosynthetic enzymes and the regulatory mechanisms modulating CoQ(10) production increases, approaches arise for the genetic engineering of CoQ(10) production in Escherichia coli and Agrobacterium tumefaciens. This review focused on approaches for CoQ(10) production, strategies used to engineer CoQ(10) production in microbes, and potential applications of CoQ(10).

  1. Synthetic Biology for Engineering Acetyl Coenzyme A Metabolism in Yeast

    PubMed Central

    2014-01-01

    ABSTRACT The yeast Saccharomyces cerevisiae is a widely used cell factory for the production of fuels, chemicals, and pharmaceuticals. The use of this cell factory for cost-efficient production of novel fuels and chemicals requires high yields and low by-product production. Many industrially interesting chemicals are biosynthesized from acetyl coenzyme A (acetyl-CoA), which serves as a central precursor metabolite in yeast. To ensure high yields in production of these chemicals, it is necessary to engineer the central carbon metabolism so that ethanol production is minimized (or eliminated) and acetyl-CoA can be formed from glucose in high yield. Here the perspective of generating yeast platform strains that have such properties is discussed in the context of a major breakthrough with expression of a functional pyruvate dehydrogenase complex in the cytosol. PMID:25370498

  2. Stability and color changes of thermally treated betanin, phyllocactin, and hylocerenin solutions.

    PubMed

    Herbach, Kirsten M; Stintzing, Florian C; Carle, Reinhold

    2006-01-25

    Thermal degradation of betanin, phyllocactin (malonyl-betanin), and hylocerenin (3' '-hydroxy-3' '-methyl-glutaryl-betanin) solutions isolated from purple pitaya (Hylocereus polyrhizus [Weber] Britton and Rose) was monitored by spectrophotometric and high-performance liquid chromatography-diode array detection (HPLC-DAD) analyses. For betanin and phyllocactin solutions, the color shift upon thermal treatment was found to be nearly identical, while hylocerenin samples exhibited an intelligibly higher chromatic steadiness. Betanin proved to be the most stable individual pigment structure, while the enhanced tinctorial stability of the integral phyllocactin and especially hylocerenin solutions was due to the formation of red degradation products exhibiting improved color retention as opposed to their respective genuine pigments. Individual structure-related stability characteristics can exclusively be assessed by HPLC-DAD analyses and may not be noticed by mere spectrophotometric assessment of color and tinctorial strength.

  3. Coenzyme world model of the origin of life.

    PubMed

    Sharov, Alexei A

    2016-06-01

    The origin of life means the emergence of heritable and evolvable self-reproduction. However the mechanisms of primordial heredity were different from those in contemporary cells. Here I argue that primordial life had no nucleic acids; instead heritable signs were represented by isolated catalytically active self-reproducing molecules, similar to extant coenzymes, which presumably colonized surfaces of oil droplets in water. The model further assumes that coenzyme-like molecules (CLMs) changed surface properties of oil droplets (e.g., by oxidizing terminal carbons), and in this way created and sustained favorable conditions for their own self-reproduction. Such niche-dependent self-reproduction is a necessary condition for cooperation between different kinds of CLMs because they have to coexist in the same oil droplets and either succeed or perish together. Additional kinds of hereditary molecules were acquired via coalescence of oil droplets carrying different kinds of CLMs or via modification of already existing CLMs. Eventually, polymerization of CLMs became controlled by other polymers used as templates; and this kind of template-based synthesis eventually resulted in the emergence of RNA-like replicons. Apparently, oil droplets transformed into the outer membrane of cells via engulfing water, stabilization of the surface, and osmoregulation. In result, the metabolism was internalized allowing cells to accumulate free-floating resources (e.g., animoacids, ATP), which was a necessary condition for the development of protein synthesis. Thus, life originated from simple but already functional molecules, and its gradual evolution towards higher complexity was driven by cooperation and natural selection.

  4. The Reaction Mechanism of Methyl-Coenzyme M Reductase

    PubMed Central

    Wongnate, Thanyaporn; Ragsdale, Stephen W.

    2015-01-01

    Methyl-coenzyme M reductase (MCR) is a nickel tetrahydrocorphinoid (coenzyme F430) containing enzyme involved in the biological synthesis and anaerobic oxidation of methane. MCR catalyzes the conversion of methyl-2-mercaptoethanesulfonate (methyl-SCoM) and N-7-mercaptoheptanoylthreonine phosphate (CoB7SH) to CH4 and the mixed disulfide CoBS-SCoM. In this study, the reaction of MCR from Methanothermobacter marburgensis, with its native substrates was investigated using static binding, chemical quench, and stopped-flow techniques. Rate constants were measured for each step in this strictly ordered ternary complex catalytic mechanism. Surprisingly, in the absence of the other substrate, MCR can bind either substrate; however, only one binary complex (MCR·methyl-SCoM) is productive whereas the other (MCR·CoB7SH) is inhibitory. Moreover, the kinetic data demonstrate that binding of methyl-SCoM to the inhibitory MCR·CoB7SH complex is highly disfavored (Kd = 56 mm). However, binding of CoB7SH to the productive MCR·methyl-SCoM complex to form the active ternary complex (CoB7SH·MCR(NiI)·CH3SCoM) is highly favored (Kd = 79 μm). Only then can the chemical reaction occur (kobs = 20 s−1 at 25 °C), leading to rapid formation and dissociation of CH4 leaving the binary product complex (MCR(NiII)·CoB7S−·SCoM), which undergoes electron transfer to regenerate Ni(I) and the final product CoBS-SCoM. This first rapid kinetics study of MCR with its natural substrates describes how an enzyme can enforce a strictly ordered ternary complex mechanism and serves as a template for identification of the reaction intermediates. PMID:25691570

  5. Coordination and binding geometry of methyl-coenzyme M in the red1m state of methyl-coenzyme M reductase.

    PubMed

    Hinderberger, Dariush; Ebner, Sieglinde; Mayr, Stefan; Jaun, Bernhard; Reiher, Markus; Goenrich, Meike; Thauer, Rudolf K; Harmer, Jeffrey

    2008-11-01

    Methane formation in methanogenic Archaea is catalyzed by methyl-coenzyme M reductase (MCR) and takes place via the reduction of methyl-coenzyme M (CH3-S-CoM) with coenzyme B (HS-CoB) to methane and the heterodisulfide CoM-S-S-CoB. MCR harbors the nickel porphyrinoid coenzyme F430 as a prosthetic group, which has to be in the Ni(I) oxidation state for the enzyme to be active. To date no intermediates in the catalytic cycle of MCRred1 (red for reduced Ni) have been identified. Here, we report a detailed characterization of MCRred1m ("m" for methyl-coenzyme M), which is the complex of MCRred1a ("a" for absence of substrate) with CH3-S-CoM. Using continuous-wave and pulse electron paramagnetic resonance spectroscopy in combination with selective isotope labeling (13C and 2H) of CH3-S-CoM, it is shown that CH3-S-CoM binds in the active site of MCR such that its thioether sulfur is weakly coordinated to the Ni(I) of F430. The complex is stable until the addition of the second substrate, HS-CoB. Results from EPR spectroscopy, along with quantum mechanical calculations, are used to characterize the electronic and geometric structure of this complex, which can be regarded as the first intermediate in the catalytic mechanism.

  6. Extra virgin olive oil phenols down-regulate lipid synthesis in primary-cultured rat-hepatocytes.

    PubMed

    Priore, Paola; Siculella, Luisa; Gnoni, Gabriele Vincenzo

    2014-07-01

    Hydroxytyrosol, tyrosol, and oleuropein, the main phenols present in extra virgin olive oil, have been reported to exert several biochemical and pharmacological effects. Here, we investigated the short-term effects of these compounds on lipid synthesis in primary-cultured rat-liver cells. Hydroxytyrosol, tyrosol and oleuropein inhibited both de novo fatty acid and cholesterol syntheses without an effect on cell viability. The inhibitory effect of individual compounds was already evident within 2 h of 25 μM phenol addition to the hepatocytes. The degree of cholesterogenesis reduction was similar for all phenol treatments (-25/30%), while fatty acid synthesis showed the following order of inhibition: hydroxytyrosol (-49%) = oleuropein (-48%) > tyrosol (-30%). A phenol-induced reduction of triglyceride synthesis was also detected. To clarify the lipid-lowering mechanism of these compounds, their influence on the activity of key enzymes of fatty acid biosynthesis (acetyl-CoA carboxylase and fatty acid synthase), triglyceride synthesis (diacylglycerol acyltransferase) and cholesterogenesis (3-hydroxy-3-methyl-glutaryl-CoA reductase) was investigated in situ by using digitonin-permeabilized hepatocytes. Acetyl-CoA carboxylase, diacylglycerol acyltransferase and 3-hydroxy-3-methyl-glutaryl-CoA reductase activities were reduced after 2 h of 25 μM phenol treatment. No change in fatty acid synthase activity was observed. Acetyl-CoA carboxylase inhibition (hydroxytyrosol, -41%, = oleuropein, -38%, > tyrosol, -17%) appears to be mediated by phosphorylation of AMP-activated protein kinase. These findings suggest that a decrease in hepatic lipid synthesis may represent a potential mechanism underlying the reported hypolipidemic effect of phenols of extra virgin olive oil.

  7. Supplementation of Coenzyme Q10 among Patients with Type 2 Diabetes Mellitus.

    PubMed

    Shen, Qiuhua; Pierce, Janet D

    2015-05-21

    Type 2 diabetes mellitus (T2DM) is a major cause of morbidity and mortality with ever increasing prevalence in the United States and worldwide. There is growing body of evidence suggesting that mitochondrial dysfunction secondary to oxidative stress plays a critical role in the pathogenesis of T2DM. Coenzyme Q10 is an important micronutrient acting on the electron transport chain of the mitochondria with two major functions: (1) synthesis of adenosine triphosphate (ATP); and (2) a potent antioxidant. Deficiency in coenzyme Q10 is often seen in patients with T2DM. Whether restoration of coenzyme Q10 will help alleviate oxidative stress, preserve mitochondrial function, and thus improve glycemic control in T2DM is unclear. This article reviews the relationships among oxidative stress, mitochondrial dysfunction, and T2DM and examines the evidence for potential use of coenzyme Q10 as a supplement for the treatment of T2DM.

  8. A coenzyme-independent decarboxylase/oxygenase cascade for the efficient synthesis of vanillin.

    PubMed

    Furuya, Toshiki; Miura, Misa; Kino, Kuniki

    2014-10-13

    Vanillin is one of the most widely used flavor compounds in the world as well as a promising versatile building block. The biotechnological production of vanillin from plant-derived ferulic acid has attracted much attention as a new alternative to chemical synthesis. One limitation of the known metabolic pathway to vanillin is its requirement for expensive coenzymes. Here, we developed a novel route to vanillin from ferulic acid that does not require any coenzymes. This artificial pathway consists of a coenzyme-independent decarboxylase and a coenzyme-independent oxygenase. When Escherichia coli cells harboring the decarboxylase/oxygenase cascade were incubated with ferulic acid, the cells efficiently synthesized vanillin (8.0 mM, 1.2 g L(-1) ) via 4-vinylguaiacol in one pot, without the generation of any detectable aromatic by-products. The efficient method described here might be applicable to the synthesis of other high-value chemicals from plant-derived aromatics.

  9. The effects of coenzyme Q10 on seizures in mice: the involvement of nitric oxide.

    PubMed

    Sattarinezhad, Elahe; Shafaroodi, Hamed; Sheikhnouri, Kiandokht; Mousavi, Zahra; Moezi, Leila

    2014-08-01

    Coenzyme Q10 is a potent antioxidant in both mitochondria and lipid membranes. It has also been recognized to have an effect on gene expression. This study was designed to investigate whether acute or subchronic treatment with coenzyme Q10 altered the seizures induced by pentylenetetrazole or electroshock in mice. We also evaluated the involvement of nitric oxide in the effects of coenzyme Q10 in pentylenetetrazole-induced seizure models. Acute oral treatment with different doses of coenzyme Q10 did not affect the seizure in intraperitoneal pentylenetetrazole, intravenous pentylenetetrazole, and electroshock models in mice. Subchronic oral administration of coenzyme Q10 (100 mg/kg or more) increased time latencies to the onset of myoclonic jerks and clonic seizures induced by intraperitoneal pentylenetetrazole and at the doses of 25 mg/kg or more increased the seizure threshold induced by intravenous infusion of pentylenetetrazole. Subchronic doses of coenzyme Q10 (50 mg/kg or more) also decreased the incidence of tonic seizures in the electroshock-induced seizure model. Moreover, acute treatment with the precursor of nitric oxide synthesis, L-arginine (60 mg/kg), led to a significant potentiation of the antiseizure effects of subchronic administration of coenzyme Q10 (400 mg/kg in intraperitoneal and 6.25 mg/kg in intravenous pentylenetetrazole tests). Acute treatment with l-NAME (5 mg/kg), a nonspecific nitric oxide synthase inhibitor, significantly attenuated the antiseizure effects of subchronic doses of coenzyme Q10 in both seizure models induced by pentylenetetrazole. On the other hand, acute administration of aminoguanidine (100 mg/kg), a specific inducible nitric oxide synthase inhibitor, did not affect the seizures in mice treated with subchronic doses of coenzyme Q10 in both intraperitoneal and intravenous pentylenetetrazole tests. In conclusion, only subchronic and not acute administration of coenzyme Q10 attenuated seizures induced by pentylenetetrazole

  10. Effect of Metabolic Stress on Coenzyme Q10 Content in Tissues of Active and Passive Rats.

    PubMed

    Kirbaeva, N V; Sharanova, N E; Baturina, V A; Zhminchenko, V M; Pertsov, S S; Vasil'ev, A V

    2016-09-01

    The dynamics of coenzyme Q10 concentration in the blood plasma, liver, and brain of passive and active rats was studied on the model of metabolic stress. This parameter was shown to differ in rats with various patterns of behavior. Dietary consumption of coenzyme Q10 in doses of 10 and 100 mg/kg body weight was followed by changes in its content in experimental animals.

  11. Hepatoprotective effect of coenzyme Q10 in rats with acetaminophen toxicity.

    PubMed

    Fouad, Amr A; Jresat, Iyad

    2012-03-01

    The potential protective effect of coenzyme Q10 against acute liver injury induced by a single dose of acetaminophen (700 mg/kg, p.o.) was investigated in rats. Coenzyme Q10 treatment was given as two i.p. injections, 10 mg/kg each, at 1 and 12 h following acetaminophen administration. Coenzyme Q10 significantly reduced the levels of serum aminotransferases, suppressed lipid peroxidation, prevented the decreases of reduced glutathione and catalase activity, decreased the elevations of tumor necrosis factor-α and nitric oxide as well as attenuating the reductions of selenium and zinc ions in liver tissue resulting from acetaminophen administration. Histopathological liver tissue damage mediated by acetaminophen was ameliorated by coenzyme Q10. Immunohistochemical analysis revealed that coenzyme Q10 significantly decreased the acetaminophen-induced overexpression of inducible nitric oxide synthase, nuclear factor-κB, caspase-3 and p53 in liver tissue. It was concluded that coenzyme Q10 protects rat liver against acute acetaminophen hepatotoxicity, most probably through its antioxidant, anti-inflammatory and antiapoptotic effects.

  12. Therapeutic effect of coenzyme Q10 against experimentally-induced hepatocellular carcinoma in rats.

    PubMed

    Fouad, Amr A; Al-Mulhim, Abdulruhman S; Jresat, Iyad

    2013-01-01

    The therapeutic potential of coenzyme Q10 was investigated in rats with hepatocellular carcinoma induced by trichloroacetic acid (0.5g/kg/day, p.o., for five days). Coenzyme Q10 treatment (0.4mg/kg/day, i.p.) was applied for four weeks following trichloroacetic acid administration. Coenzyme Q10 significantly suppressed lipid peroxidation, prevented the depletion of reduced glutathione and superoxide dismutase activity, and decreased the elevations of tumor necrosis factor-α and nitric oxide in liver tissue of rats with hepatocellular carcinoma. Also, the histopathological dysplastic changes induced by trichloroacetic acid in liver tissue were ameliorated by coenzyme Q10. Immunohistochemical analysis revealed that coenzyme Q10 significantly decreased the expression of hepPar-1, alpha-fetoprotein, inducible nitric oxide synthase, cyclooxygenase-2 and nuclear factor-κB in liver tissue of rats with hepatocellular carcinoma. It was concluded that coenzyme Q10 may represent a potential therapeutic option for liver carcinogenesis.

  13. Behavioral improvement after chronic administration of coenzyme Q10 in P301S transgenic mice.

    PubMed

    Elipenahli, Ceyhan; Stack, Cliona; Jainuddin, Shari; Gerges, Meri; Yang, Lichuan; Starkov, Anatoly; Beal, M Flint; Dumont, Magali

    2012-01-01

    Coenzyme Q10 is a key component of the electron transport chain which plays an essential role in ATP production and also has antioxidant effects. Neuroprotective effects of coenzyme Q10 have been reported in both in vitro and in vivo models of neurodegenerative diseases. However, its effects have not been studied in cells or in animals with tau induced pathology. In this report, we administered coenzyme Q10 to transgenic mice with the P301S tau mutation, which causes fronto-temporal dementia in man. These mice develop tau hyperphosphorylation and neurofibrillary tangles in the brain. Coenzyme Q10 improved survival and behavioral deficits in the P301S mice. There was a modest reduction in phosphorylated tau in the cortex of P301S mice. We also examined the effects of coenzyme Q10 treatment on the electron transport chain enzymes, the mitochondrial antioxidant enzymes, and the tricarboxylic acid cycle. There was a significant increase in complex I activity and protein levels, and a reduction in lipid peroxidation. Our data show that coenzyme Q10 significantly improved behavioral deficits and survival in transgenic mice with the P301S tau mutation, upregulated key enzymes of the electron transport chain, and reduced oxidative stress.

  14. Coenzyme Q10 and Oxidative Stress: Inflammation Status in Hepatocellular Carcinoma Patients after Surgery.

    PubMed

    Liu, Hsiao-Tien; Cheng, Shao-Bin; Huang, Yi-Chia; Huang, Yin-Tzu; Lin, Ping-Ting

    2017-01-04

    (1) Background: Hepatocellular carcinoma (HCC) is the second leading cause of cancer deaths worldwide, and surgical resection is the main treatment for HCC. To date, no published study has examined the status of coenzyme Q10 in patients with HCC after surgery. Thus, the purpose of this study was to investigate the correlations between the level of coenzyme Q10, oxidative stress, and inflammation in patients with HCC after surgery; (2) Methods: 71 primary HCC patients were recruited. Levels of coenzyme Q10, vitamin E, oxidative stress (malondialdehyde), antioxidant enzymes activity (superoxidase dismutase, catalase, and glutathione peroxidase), and inflammatory markers (high sensitivity C-reactive protein; tumor necrosis factor-α; and interleukin-6) were measured; (3) Results: Patients with HCC had a significantly lower levels of coenzyme Q10 (p = 0.01) and oxidative stress (p < 0.01), and significantly higher levels of antioxidant enzymes activities and inflammation after surgery (p < 0.05). The level of coenzyme Q10 was significantly positively correlated with antioxidant capacity (vitamin E and glutathione peroxidase activity) and negatively correlated with inflammation markers after surgery; (4) Conclusion: Hepatocarcinogenesis is associated with oxidative stress, and coenzyme Q10 may be considered an antioxidant therapy for patients with HCC, particularly those with higher inflammation after surgery.

  15. Coenzyme Q10 and Oxidative Stress: Inflammation Status in Hepatocellular Carcinoma Patients after Surgery

    PubMed Central

    Liu, Hsiao-Tien; Cheng, Shao-Bin; Huang, Yi-Chia; Huang, Yin-Tzu; Lin, Ping-Ting

    2017-01-01

    (1) Background: Hepatocellular carcinoma (HCC) is the second leading cause of cancer deaths worldwide, and surgical resection is the main treatment for HCC. To date, no published study has examined the status of coenzyme Q10 in patients with HCC after surgery. Thus, the purpose of this study was to investigate the correlations between the level of coenzyme Q10, oxidative stress, and inflammation in patients with HCC after surgery; (2) Methods: 71 primary HCC patients were recruited. Levels of coenzyme Q10, vitamin E, oxidative stress (malondialdehyde), antioxidant enzymes activity (superoxidase dismutase, catalase, and glutathione peroxidase), and inflammatory markers (high sensitivity C-reactive protein; tumor necrosis factor-α; and interleukin-6) were measured; (3) Results: Patients with HCC had a significantly lower levels of coenzyme Q10 (p = 0.01) and oxidative stress (p < 0.01), and significantly higher levels of antioxidant enzymes activities and inflammation after surgery (p < 0.05). The level of coenzyme Q10 was significantly positively correlated with antioxidant capacity (vitamin E and glutathione peroxidase activity) and negatively correlated with inflammation markers after surgery; (4) Conclusion: Hepatocarcinogenesis is associated with oxidative stress, and coenzyme Q10 may be considered an antioxidant therapy for patients with HCC, particularly those with higher inflammation after surgery. PMID:28054958

  16. The relationship between coenzyme Q10, oxidative stress, and antioxidant enzymes activities and coronary artery disease.

    PubMed

    Lee, Bor-Jen; Lin, Yi-Chin; Huang, Yi-Chia; Ko, Ya-Wen; Hsia, Simon; Lin, Ping-Ting

    2012-01-01

    A higher oxidative stress may contribute to the pathogenesis of coronary artery disease (CAD). The purpose of this study was to investigate the relationship between coenzyme Q10 concentration and lipid peroxidation, antioxidant enzymes activities and the risk of CAD. Patients who were identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery were assigned to the case group (n = 51). The control group (n = 102) comprised healthy individuals with normal blood biochemical values. The plasma coenzyme Q10, malondialdehyde (MDA) and antioxidant enzymes activities (catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx)) were measured. Subjects with CAD had significant lower plasma coenzyme Q10, CAT and GPx activities and higher MDA and SOD levels compared to those of the control group. The plasma coenzyme Q10 was positively correlated with CAT and GPx activities and negatively correlated with MDA and SOD. However, the correlations were not significant after adjusting for the potential confounders of CAD with the exception of SOD. A higher level of plasma coenzyme Q10 (≥ 0.52 μmol/L) was significantly associated with reducing the risk of CAD. Our results support the potential cardioprotective impact of coenzyme Q10.

  17. Protein motifs involved in coenzyme interaction and enzymatic efficiency in anabaena ferredoxin-NADP+ reductase.

    PubMed

    Peregrina, José R; Herguedas, Beatriz; Hermoso, Juan A; Martínez-Júlvez, Marta; Medina, Milagros

    2009-04-14

    Ferredoxin-NADP+ reductases (FNRs) must determine the coenzyme specificity and allow the transient encounter between N5 of its flavin cofactor and C4 of the coenzyme nicotinamide for efficient hydride transfer. Combined site-directed replacements in different putative determinants of the FNR coenzyme specificity were simultaneously produced. The resulting variants were structurally and functionally analyzed for their binding and hydride transfer abilities to the FNR physiological coenzyme NADP+/H, as well as to NAD+/H. The previously studied Y303S mutation is the only one that significantly enhances specificity for NAD+. Combination of mutations from the pyrophosphate or 2'-phosphate regions, even including Y303S, does not improve activity with NAD+, despite structures of these FNRs show how particular coenzyme-binding regions resembled motifs found in NAD+/H-dependent enzymes of the FNR family. Therefore, the "rational approach" did not succeed well, and coenzyme specificity redesign in the FNR family will be more complex than that anticipated in other NADP+/NAD+ families.

  18. A role for coenzyme M (2-mercaptoethanesulfonic acid) in a bacterial pathway of aliphatic epoxide carboxylation

    PubMed Central

    Allen, Jeffrey R.; Clark, Daniel D.; Krum, Jonathan G.; Ensign, Scott A.

    1999-01-01

    The bacterial metabolism of short-chain aliphatic alkenes occurs via oxidation to epoxyalkanes followed by carboxylation to β-ketoacids. Epoxyalkane carboxylation requires four enzymes (components I–IV), NADPH, NAD+, and a previously unidentified nucleophilic thiol. In the present work, coenzyme M (2-mercaptoethanesulfonic acid), a compound previously found only in the methanogenic Archaea where it serves as a methyl group carrier and activator, has been identified as the thiol and central cofactor of aliphatic epoxide carboxylation in the Gram-negative bacterium Xanthobacter strain Py2. Component I catalyzed the addition of coenzyme M to epoxypropane to form a β-hydroxythioether, 2-(2-hydroxypropylthio)ethanesulfonate. Components III and IV catalyzed the NAD+-dependent stereoselective dehydrogenation of R- and S-enantiomers of 2-(2-hydroxypropylthio)ethanesulfonate to form 2-(2-ketopropylthio)ethanesulfonate. Component II catalyzed the NADPH-dependent cleavage and carboxylation of the β-ketothioether to form acetoacetate and coenzyme M. These findings evince a newfound versatility for coenzyme M as a carrier and activator of alkyl groups longer in chain-length than methane, a function for coenzyme M in a catabolic pathway of hydrocarbon oxidation, and the presence of coenzyme M in the bacterial domain of the phylogenetic tree. These results serve to unify bacterial and Archaeal metabolism further and showcase diverse biological functions for an elegantly simple organic molecule. PMID:10411892

  19. Behavioral Improvement after Chronic Administration of Coenzyme Q10 in P301S Transgenic Mice

    PubMed Central

    Elipenahli, Ceyhan; Stack, Cliona; Jainuddin, Shari; Gerges, Meri; Yang, Lichuan; Starkov, Anatoly; Beal, M. Flint; Dumont, Magali

    2012-01-01

    Coenzyme Q10 is a key component of the electron transport chain which plays an essential role in ATP production and also has antioxidant effects. Neuroprotective effects of coenzyme Q10 have been reported in both in vitro and in vivo models of neurodegenerative diseases. However, its effects have not been studied in cells or in animals with tau induced pathology. In this report, we administered coenzyme Q10 to transgenic mice with the P301S tau mutation, which causes fronto-temporal dementia in man. These mice develop tau hyperphosphorylation and neurofibrillary tangles in the brain. Coenzyme Q10 improved survival and behavioral deficits in the P301S mice. There was a modest reduction in phosphorylated tau in the cortex of P301S mice. We also examined the effects of coenzyme Q10 treatment on the electron transport chain enzymes, the mitochondrial antioxidant enzymes, and the tricarboxylic acid cycle. There was a significant increase in complex I activity and protein levels, and a reduction in lipid peroxidation. Our data show that coenzyme Q10 significantly improved behavioral deficits and survival in transgenic mice with the P301S tau mutation, upregulated key enzymes of the electron transport chain, and reduced oxidative stress. PMID:21971408

  20. Oxidative Stress, Disrupted Energy Metabolism, and Altered Signaling Pathways in Glutaryl-CoA Dehydrogenase Knockout Mice: Potential Implications of Quinolinic Acid Toxicity in the Neuropathology of Glutaric Acidemia Type I.

    PubMed

    Seminotti, Bianca; Amaral, Alexandre Umpierrez; Ribeiro, Rafael Teixeira; Rodrigues, Marília Danyelle Nunes; Colín-González, Ana Laura; Leipnitz, Guilhian; Santamaría, Abel; Wajner, Moacir

    2016-11-01

    We investigated the effects of an acute intrastriatal QUIN administration on cellular redox and bioenergetics homeostasis, as well as on important signaling pathways in the striatum of wild-type (Gcdh (+/+) , WT) and knockout mice for glutaryl-CoA dehydrogenase (Gcdh (-/-) ) fed a high lysine (Lys, 4.7 %) chow. QUIN increased lactate release in both Gcdh (+/+) and Gcdh (-/-) mice and reduced the activities of complex IV and creatine kinase only in the striatum of Gcdh (-/-) mice. QUIN also induced lipid and protein oxidative damage and increased the generation of reactive nitrogen species, as well as the activities of the antioxidant enzymes glutathione peroxidase, superoxide dismutase 2, and glutathione-S-transferase in WT and Gcdh (-/-) animals. Furthermore, QUIN induced DCFH oxidation (reactive oxygen species production) and reduced GSH concentrations (antioxidant defenses) in Gcdh (-/-) . An early increase of Akt and phospho-Erk 1/2 in the cytosol and Nrf2 in the nucleus was also observed, as well as a decrease of cytosolic Keap1caused by QUIN, indicating activation of the Nrf2 pathway mediated by Akt and phospho-Erk 1/2, possibly as a compensatory protective mechanism against the ongoing QUIN-induced toxicity. Finally, QUIN increased NF-κB and diminished IκBα expression, evidencing a pro-inflammatory response. Our data show a disruption of energy and redox homeostasis associated to inflammation induced by QUIN in the striatum of Gcdh (-/-) mice submitted to a high Lys diet. Therefore, it is presumed that QUIN may possibly contribute to the pathophysiology of striatal degeneration in children with glutaric aciduria type I during inflammatory processes triggered by infections or vaccinations.

  1. A randomized trial of coenzyme Q10 in mitochondrial disorders.

    PubMed

    Glover, Elisa I; Martin, Joan; Maher, Amy; Thornhill, Rebecca E; Moran, Gerald R; Tarnopolsky, Mark A

    2010-11-01

    Case reports and open-label studies suggest that coenzyme Q(10) (CoQ(10)) treatment may have beneficial effects in mitochondrial disease patients; however, controlled trials are warranted to clinically prove its effectiveness. Thirty patients with mitochondrial cytopathy received 1200 mg/day CoQ(10) for 60 days in a randomized, double-blind, cross-over trial. Blood lactate, urinary markers of oxidative stress, body composition, activities of daily living, quality of life, forearm handgrip strength and oxygen desaturation, cycle exercise cardiorespiratory variables, and brain metabolites were measured. CoQ(10) treatment attenuated the rise in lactate after cycle ergometry, increased (∽1.93 ml) VO(2)/kg lean mass after 5 minutes of cycling (P < 0.005), and decreased gray matter choline-containing compounds (P < 0.05). Sixty days of moderate- to high-dose CoQ(10) treatment had minor effects on cycle exercise aerobic capacity and post-exercise lactate but did not affect other clinically relevant variables such as strength or resting lactate.

  2. Muscle coenzyme Q deficiency in familial mitochondrial encephalomyopathy.

    PubMed Central

    Ogasahara, S; Engel, A G; Frens, D; Mack, D

    1989-01-01

    The electron transport system of muscle mitochondria was examined in a familial syndrome of lactacidemia, mitochondrial myopathy, and encephalopathy. The propositus, a 14-year-old female, and her 12-year-old sister had suffered from progressive muscle weakness, abnormal fatigability, and central nervous system dysfunction since early childhood. In the propositus, the state 3 respiratory rate of muscle mitochondria with NADH-linked substrates and with succinate was markedly reduced. The levels of cytochromes a + a3, b, and c + c1 were normal. The activities of complexes I, II, III, and IV of the electron transport chain were normal or increased. By contrast, the activities of complex I-III and of complex II-III, both of which need coenzyme Q10 (CoQ10), were abnormally low. On direct measurement, the mitochondrial CoQ10 content was 3.7% of the mean value observed in 10 controls. Serum and cultured fibroblasts of the propositus had normal CoQ10 contents. In the younger sister, the respiratory activities and CoQ10 level of muscle mitochondria were similar to those observed in the propositus. The findings establish CoQ10 deficiency as a cause of a familial mitochondrial cytopathy and suggest that the disease results from a tissue-specific defect of CoQ10 biosynthesis. PMID:2928337

  3. Coenzyme Q10 protects hair cells against aminoglycoside.

    PubMed

    Sugahara, Kazuma; Hirose, Yoshinobu; Mikuriya, Takefumi; Hashimoto, Makoto; Kanagawa, Eiju; Hara, Hirotaka; Shimogori, Hiroaki; Yamashita, Hiroshi

    2014-01-01

    It is well known that the production of free radicals is associated with sensory cell death induced by an aminoglycoside. Many researchers have reported that antioxidant reagents protect sensory cells in the inner ear, and coenzyme Q10 (CoQ10) is an antioxidant that is consumed as a health food in many countries. The purpose of this study was to investigate the role of CoQ10 in mammalian vestibular hair cell death induced by aminoglycoside. Cultured utricles of CBA/CaN mice were divided into three groups (control group, neomycin group, and neomycin + CoQ10 group). In the neomycin group, utricles were cultured with neomycin (1 mM) to induce hair cell death. In the neomycin + CoQ10 group, utricles were cultured with neomycin and water-soluble CoQ10 (30-0.3 µM). Twenty-four hours after exposure to neomycin, the cultured tissues were fixed, and vestibular hair cells were labeled using an anti-calmodulin antibody. Significantly more hair cells survived in the neomycin + CoQ10 group than in the neomycin group. These data indicate that CoQ10 protects sensory hair cells against neomycin-induced death in the mammalian vestibular epithelium; therefore, CoQ10 may be useful as a protective drug in the inner ear.

  4. Coenzyme Q10 analytical determination in biological matrices and pharmaceuticals.

    PubMed

    Lucangioli, Silvia; Martinefski, Manuela; Tripodi, Valeria

    2016-06-01

    In recent years, the analytical determination of coenzyme Q10 (CoQ10) has gained importance in clinical diagnosis and in pharmaceutical quality control. CoQ10 is an important cofactor in the mitochondrial respiratory chain and a potent endogenous antioxidant. CoQ10 deficiency is often associated with numerous diseases and patients with these conditions may benefit from administration of supplements of CoQ10. In this regard, it has been observed that the best benefits are obtained when CoQ10 deficiency is diagnosed and treated early. Therefore, it is of great value to develop analytical methods for the detection and quantification of CoQ10 in this type of disease. The methods above mentioned should be simple enough to be used in routine clinical laboratories as well as in quality control of pharmaceutical formulations containing CoQ10. Here, we discuss the advantages and disadvantages of different methods of CoQ10 analysis.

  5. Properties of Succinyl-Coenzyme A:d-Citramalate Coenzyme A Transferase and Its Role in the Autotrophic 3-Hydroxypropionate Cycle of Chloroflexus aurantiacus

    PubMed Central

    Friedmann, Silke; Alber, Birgit E.; Fuchs, Georg

    2006-01-01

    The phototrophic bacterium Chloroflexus aurantiacus uses the 3-hydroxypropionate cycle for autotrophic CO2 fixation. This cycle starts with acetyl-coenzyme A (CoA) and produces glyoxylate. Glyoxylate is an unconventional cell carbon precursor that needs special enzymes for assimilation. Glyoxylate is combined with propionyl-CoA to β-methylmalyl-CoA, which is converted to citramalate. Cell extracts catalyzed the succinyl-CoA-dependent conversion of citramalate to acetyl-CoA and pyruvate, the central cell carbon precursor. This reaction is due to the combined action of enzymes that were upregulated during autotrophic growth, a coenzyme A transferase with the use of succinyl-CoA as the CoA donor and a lyase cleaving citramalyl-CoA to acetyl-CoA and pyruvate. Genomic analysis identified a gene coding for a putative coenzyme A transferase. The gene was heterologously expressed in Escherichia coli and shown to code for succinyl-CoA:d-citramalate coenzyme A transferase. This enzyme, which catalyzes the reaction d-citramalate + succinyl-CoA → d-citramalyl-CoA + succinate, was purified and studied. It belongs to class III of the coenzyme A transferase enzyme family, with an aspartate residue in the active site. The homodimeric enzyme composed of 44-kDa subunits was specific for succinyl-CoA as a CoA donor but also accepted d-malate and itaconate instead of d-citramalate. The CoA transferase gene is part of a cluster of genes which are cotranscribed, including the gene for d-citramalyl-CoA lyase. It is proposed that the CoA transferase and the lyase catalyze the last two steps in the glyoxylate assimilation route. PMID:16952935

  6. The antioxidant status and concentrations of coenzyme Q10 and vitamin E in metabolic syndrome.

    PubMed

    Yen, Chi-Hua; Yang, Nae-Cherng; Lee, Bor-Jen; Lin, Jui-Yuan; Hsia, Simon; Lin, Ping-Ting

    2013-01-01

    The purpose of this study was to investigate the levels of coenzyme Q10 and vitamin E and the antioxidant status in subjects with metabolic syndrome (MS). Subjects with MS (n = 72) were included according to the criteria for MS. The non-MS group (n = 105) was comprised of healthy individuals with normal blood biochemical values. The plasma coenzyme Q10, vitamin E concentrations, lipid profiles, and antioxidant enzymes levels (catalase, superoxide dismutase, and glutathione peroxidase) were measured. The subjects with MS had significantly higher concentrations of plasma coenzyme Q10 and vitamin E than those in the non-MS group, but these differences were not significant after being normalized for triglyceride level. The levels of antioxidant enzymes were significantly lower in the MS group than in the non-MS group. The subjects with the higher antioxidant enzymes activities had significant reductions in the risk of MS (P < 0.01) after being adjusted for coenzyme Q10 and vitamin E. In conclusion, the subjects with MS might be under higher oxidative stress resulting in low levels of antioxidant enzyme activities. A higher level of antioxidant enzymes activities was significantly associated with a reduction in the risk of MS independent of the levels of coenzyme Q10 and vitamin E.

  7. The structure of formylmethanofuran: tetrahydromethanopterin formyltransferase in complex with its coenzymes.

    PubMed

    Acharya, Priyamvada; Warkentin, Eberhard; Ermler, Ulrich; Thauer, Rudolf K; Shima, Seigo

    2006-03-31

    Formylmethanofuran:tetrahydromethanopterin formyltransferase is an essential enzyme in the one-carbon metabolism of methanogenic and sulfate-reducing archaea and of methylotrophic bacteria. The enzyme, which is devoid of a prosthetic group, catalyzes the reversible formyl transfer between the two substrates coenzyme methanofuran and coenzyme tetrahydromethanopterin (H4MPT) in a ternary complex catalytic mechanism. The structure of the formyltransferase without its coenzymes has been determined earlier. We report here the structure of the enzyme in complex with both coenzymes at a resolution of 2.0 A. Methanofuran, characterized for the first time in an enzyme structure, is embedded in an elongated cleft at the homodimer interface and fixed by multiple hydrophobic interactions. In contrast, tetrahydromethanopterin is only weakly bound in a shallow and wide cleft that provides two binding sites. It is assumed that the binding of the bulky coenzymes induces conformational changes of the polypeptide in the range of 3A that close the H4MPT binding cleft and position the reactive groups of both substrates optimally for the reaction. The key residue for substrate binding and catalysis is the strictly conserved Glu245. Glu245, embedded in a hydrophobic region and completely buried upon tetrahydromethanopterin binding, is presumably protonated prior to the reaction and is thus able to stabilize the tetrahedral oxyanion intermediate generated by the nucleophilic attack of the N5 atom of tetrahydromethanopterin onto the formyl carbon atom of formylmethanofuran.

  8. Coenzyme Q10 (ubiquinol-10) supplementation improves oxidative imbalance in children with trisomy 21.

    PubMed

    Miles, Michael V; Patterson, Bonnie J; Chalfonte-Evans, Melinda L; Horn, Paul S; Hickey, Francis J; Schapiro, Mark B; Steele, Paul E; Tang, Peter H; Hotze, Stephanie L

    2007-12-01

    Endogenous coenzyme Q10 is an essential cofactor in the mitochondrial respiratory chain, a potent antioxidant, and a potential biomarker for systemic oxidative status. Evidence of oxidative stress was reported in individuals with trisomy 21. In this study, 14 children with trisomy 21 had significantly increased (P < 0.0001) plasma ubiquinone-10 (the oxidized component of coenzyme Q10) compared with 12 age- and sex-matched healthy children (historical controls). Also, the mean ratio of ubiquinol-10 (the biochemically reduced component):total coenzyme Q10 was significantly decreased (P < 0.0001). After 3 months of ubiquinol-10 supplementation (10 mg/kg/day) to 10 patients with trisomy 21, the mean ubiquinol-10:total coenzyme Q10 ratio increased significantly (P < 0.0001) above baseline values, and 80% of individual ratios were within normal range. No significant or unexpected adverse effects were reported by participants. To our knowledge, this is the first study to indicate that the pro-oxidant state in plasma of children with trisomy 21, as assessed by ubiquinol-10:total coenzyme Q10 ratio, may be normalized with ubiquinol-10 supplementation. Further studies are needed to determine whether correction of this oxidant imbalance improves clinical outcomes of children with trisomy 21.

  9. Reduction of ascites mortality in broilers by coenzyme Q10.

    PubMed

    Geng, A L; Guo, Y M; Yang, Y

    2004-09-01

    Effects of coenzyme Q10 (CoQ10) supplementation on growth performance and ascites were studied in broilers. One hundred eighty 1-d-old Arbor Acre male broiler chicks were randomly allocated into 3 groups with 6 replicates each. From d 8, the diets were supplemented with CoQ10 at levels of 0, 20, and 40 mg/kg, respectively. From d 15 to 21, all the chicks were exposed to low ambient temperature (15 to 18 degrees C) to induce ascites. Average feed intake, BW gain, and feed conversion ratio of the broilers during 0 to 3 wk, 3 to 6 wk, and 0 to 6 wk were measured. The results showed that there were no influences observed on broilers' growth performance, but the mortality due to ascites was reduced by CoQ10 supplementation (P < or = 0.05). Erythrocyte osmotic fragility (EOF) was significantly decreased by 40 mg/kg CoQ10 compared with the control, but no significant changes were observed on blood packed cell volume (PCV) among the treatments. Pulmonary arterial diastolic pressure was significantly decreased on d 36, but no significant changes were observed on right ventricular pressure (RVP), pulmonary arterial systolic pressure, and the maximum change ratio of right intraventricular pressure (+/- dp/ dtmax). Ascites heart index (AHI) was significantly decreased by 40 mg/kg CoQ10 supplementation (P < or = 0.05). The results of this study suggested that CoQ10 has a beneficial effect in reducing ascites mortality in broilers, and 40 mg/kg CoQ10 seems to be more effective than 20 mg/ kg CoQ10.

  10. Haploinsufficiency of COQ4 causes coenzyme Q10 deficiency

    PubMed Central

    Salviati, Leonardo; Trevisson, Eva; Hernandez, Maria Angeles Rodriguez; Casarin, Alberto; Pertegato, Vanessa; Doimo, Mara; Cassina, Matteo; Agosto, Caterina; Desbats, Maria Andrea; Sartori, Geppo; Sacconi, Sabrina; Memo, Luigi; Zuffardi, Orsetta; Artuch, Rafael; Quinzii, Catarina; DiMauro, Salvatore; Hirano, Michio; Santos-Ocaña, Carlos; Navas, Plácido

    2013-01-01

    Background COQ4 encodes a protein that organises the multienzyme complex for the synthesis of coenzyme Q10 (CoQ10). A 3.9 Mb deletion of chromosome 9q34.13 was identified in a 3-year-old boy with mental retardation, encephalomyopathy and dysmorphic features. Because the deletion encompassed COQ4, the patient was screened for CoQ10 deficiency. Methods A complete molecular and biochemical characterisation of the patient’s fibroblasts and of a yeast model were performed. Results The study found reduced COQ4 expression (48% of controls), CoQ10 content and biosynthetic rate (44% and 43% of controls), and activities of respiratory chain complex II+III. Cells displayed a growth defect that was corrected by the addition of CoQ10 to the culture medium. Knockdown of COQ4 in HeLa cells also resulted in a reduction of CoQ10. Diploid yeast haploinsufficient for COQ4 displayed similar CoQ deficiency. Haploinsufficency of other genes involved in CoQ10 biosynthesis does not cause CoQ deficiency, underscoring the critical role of COQ4. Oral CoQ10 supplementation resulted in a significant improvement of neuromuscular symptoms, which reappeared after supplementation was temporarily discontinued. Conclusion Mutations of COQ4 should be searched for in patients with CoQ10 deficiency and encephalomyopathy; patients with genomic rearrangements involving COQ4 should be screened for CoQ10 deficiency, as they could benefit from supplementation. PMID:22368301

  11. [Production of coenzyme Q10 by metabolically engineered Escherichia coli].

    PubMed

    Dai, Guanping; Miao, Liangtian; Sun, Tao; Li, Qingyan; Xiao, Dongguang; Zhang, Xueli

    2015-02-01

    Coenzyme Q10 (CoQ10) is a lipophilic antioxidant that improves human immunity, delays senility and enhances the vitality of the human body and has wide applications in pharmaceutical and cosmetic industries. Microbial fermentation is a sustainable way to produce CoQ10, and attracts increased interest. In this work, the native CoQ8 synthetic pathway of Escherichia coli was replaced by the CoQ10 synthetic pathway through integrating decaprenyl diphosphate synthase gene (dps) from Rhodobacter sphaeroides into chromosome of E. coli ATCC 8739, followed by deletion of the native octaprenyl diphosphate synthase gene (ispB). The resulting strain GD-14 produced 0.68 mg/L CoQ10 with a yield of 0.54 mg/g DCW. Modulation of dxs and idi genes of the MEP pathway and ubiCA genes in combination led to 2.46-fold increase of CoQ10 production (from 0.54 to 1.87 mg/g DCW). Recruiting glucose facilitator protein of Zymomonas mobilis to replace the native phosphoenolpyruvate: carbohydrate phosphotransferase systems (PTS) further led to a 16% increase of CoQ10 yield. Finally, fed-batch fermentation of the best strain GD-51 was performed, which produced 433 mg/L CoQ10 with a yield of 11.7 mg/g DCW. To the best of our knowledge, this was the highest CoQ10 titer and yield obtained for engineered E. coli.

  12. Clinical aspects of coenzyme Q10: an update.

    PubMed

    Littarru, Gian Paolo; Tiano, Luca

    2010-03-01

    The fundamental role of coenzyme Q(10) (CoQ(10)) in mitochondrial bioenergetics and its well-acknowledged antioxidant properties constitute the basis for its clinical applications, although some of its effects may be related to a gene induction mechanism. Cardiovascular disease is still the main field of study and the latest findings confirm a role of CoQ(10) in improving endothelial function. The possible relation between CoQ(10) deficiency and statin side effects is highly debated, particularly the key issue of whether CoQ(10) supplementation counteracts statin myalgias. Furthermore, in cardiac patients, plasma CoQ(10) was found to be an independent predictor of mortality. Studies on CoQ(10) and physical exercise have confirmed its effect in improving subjective fatigue sensation and physical performance and in opposing exercise-related damage. In the field of mitochondrial myopathies, primary CoQ(10) deficiencies have been identified, involving different genes of the CoQ(10) biosynthetic pathway; some of these conditions were found to be highly responsive to CoQ(10) administration. The initial observations of CoQ(10) effects in Parkinson's and Huntington's diseases have been extended to Friedreich's ataxia, where CoQ(10) and other quinones have been tested. CoQ(10) is presently being used in a large phase III trial in Parkinson's disease. CoQ(10) has been found to improve sperm count and motility on asthenozoospermia. Moreover, for the first time CoQ(10) was found to decrease the incidence of preeclampsia in pregnancy. The ability of CoQ(10) to mitigate headache symptoms in adults was also verified in pediatric and adolescent populations.

  13. Equilibrium concentrations for pyruvate dehydrogenase and the citric acid cycle at specified concentrations of certain coenzymes.

    PubMed

    Alberty, Robert A

    2004-04-01

    It is of interest to calculate equilibrium compositions of systems of biochemical reactions at specified concentrations of coenzymes because these reactants tend to be in steady states. Thermodynamic calculations under these conditions require the definition of a further transformed Gibbs energy G" by use of a Legendre transform. These calculations are applied to the pyruvate dehydrogenase reaction plus the citric acid cycle, but steady-state concentrations of CoA, acetyl-CoA and succinyl-CoA cannot be specified because they are involved in the conservation of carbon atoms. These calculations require the use of linear algebra to obtain further transformed Gibbs energies of formation of reactants and computer programs to calculate equilibrium compositions. At specified temperature, pH, ionic strength and specified concentrations of several coenzymes, the equilibrium composition depends on the specified concentrations of the coenzymes and the initial amounts of reactants.

  14. Dual coenzyme activities of high-Km aldehyde dehydrogenase from rat liver mitochondria.

    PubMed

    Tsai, C S; Senior, D J

    1990-04-01

    Various kinetic approaches were carried out to investigate kinetic attributes for the dual coenzyme activities of mitochondrial aldehyde dehydrogenase from rat liver. The enzyme catalyses NAD(+)- and NADP(+)-dependent oxidations of ethanal by an ordered bi-bi mechanism with NAD(P)+ as the first reactant bound and NAD(P)H as the last product released. The two coenzymes presumably interact with the kinetically identical site. NAD+ forms the dynamic binary complex with the enzyme, while the enzyme-NAD(P)H complex formation is associated with conformation change(s). A stopped-flow burst of NAD(P)H formation, followed by a slower steady-state turnover, suggests that either the deacylation or the release of NAD(P)H is rate limiting. Although NADP+ is reduced by a faster burst rate, NAD+ is slightly favored as the coenzyme by virtue of its marginally faster turnover rate.

  15. Real time monitoring of on-chip coenzyme regeneration with SPR and DPI.

    PubMed

    Feng, Xiaoyi; Gao, Fei; Qin, Peiyong; Ma, Guanghui; Su, Zhiguo; Ge, Jia; Wang, Ping; Zhang, Songping

    2013-02-19

    We report in this work real time characterization of enzyme-coenzyme binding by using surface plasmon resonance (SPR) and dual polarization interferometry (DPI) analyses. Results showed that diaphorase (DP) and lactate dehydrogenases (LDH) had distinct binding selectivity and preference over reduced and oxidized states of coenzyme NAD(H). On the basis of that, DP and LDH were chosen as indicator enzymes to distinguish the specific state of surface-bound NAD(H). The transformation between NADH and NAD(+) during enzyme-catalyzed redox reactions was therefore transduced into variation in interaction signals as indicated via the binding status of the indicator enzymes as detected with both SPR and DPI. This real time molecule-specific detection strategy revealed quick and direct reflection of the state and reactivity of the coenzyme, promising a unique way of precise molecular interaction analysis.

  16. Atorvastatin reduces the myocardial content of coenzyme Q10 in isoproterenol-induced heart failure in rats.

    PubMed

    Andalib, S; Shayanfar, A; Khorrami, A; Maleki-Dijazi, N; Garjani, A

    2014-05-01

    The present study was aimed to study the effects of different doses of atorvastatin on Co Q10 content in the myocardium tissue in rats. A subcutaneous injection of isoproterenol (5 mg/kg/day) for 10 days was used for the induction of heart failure. Rats were randomly assigned to control, treatment with atorvastatin (5, 10, 20 mg/kg/day) and treatment with atorvastatin plus coenzyme Q10 (10 mg/kg/day). Coenzyme Q10 content of myocardium was measured using HPLC method with UV detector after hemodynamic parameters measurements. The malondialdehyde (MDA) content of the myocardium was evaluated in order to determine coenzyme Q10 antioxidative effect. A high dose of atorvastatin (20 mg/kg/day) was significantly reduced the myocardium content of coenzyme Q10 as compared with isoproterenol treated group (p<0.001). Compared with atorvastatin alone treated animals, co-administration of coenzyme Q10 with atorvastatin was improved the level of coenzyme Q10 in the myocardium (p<0.05, p<0.001). Increasing the dose of atorvastatin also led to increase in MDA content of the myocardium (p<0.01). Serum lipid profile showed no changes in atorvastatin treated groups. The results of this study demonstrate that high doses of atorvastatin reduce coenzyme Q10 content of the myocardium and increase lipid peroxidation in myocardium which is reversed by coenzyme Q10 co-administration.

  17. 77 FR 72385 - Certain Coenzyme Q10 Products and Methods of Making Same; Commission Determination (1) To Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-05

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Certain Coenzyme Q10 Products and Methods of Making Same; Commission Determination (1) To Review... into the United States of certain coenzyme Q10 products by reason of infringement of certain claims...

  18. Succinyl-CoA:3-Sulfinopropionate CoA-Transferase from Variovorax paradoxus Strain TBEA6, a Novel Member of the Class III Coenzyme A (CoA)-Transferase Family

    PubMed Central

    Schürmann, Marc; Hirsch, Beatrice; Wübbeler, Jan Hendrik; Stöveken, Nadine

    2013-01-01

    The act gene of Variovorax paradoxus TBEA6 encodes a succinyl-CoA:3-sulfinopropionate coenzyme A (CoA)-transferase, ActTBEA6 (2.8.3.x), which catalyzes the activation of 3-sulfinopropionate (3SP), an intermediate during 3,3′-thiodipropionate (TDP) degradation. In a previous study, accumulation of 3SP was observed in a Tn5::mob-induced mutant defective in growth on TDP. In contrast to the wild type and all other obtained mutants, this mutant showed no growth when 3SP was applied as the sole source of carbon and energy. The transposon Tn5::mob was inserted in a gene showing high homology to class III CoA-transferases. In the present study, analyses of the translation product clearly allocated ActTBEA6 to this protein family. The predicted secondary structure indicates the lack of a C-terminal α-helix. ActTBEA6 was heterologously expressed in Escherichia coli Lemo21(DE3) and was then purified by Ni-nitrilotriacetic acid (NTA) affinity chromatography. Analytical size exclusion chromatography revealed a homodimeric structure with a molecular mass of 96 ± 3 kDa. Enzyme assays identified succinyl-CoA, itaconyl-CoA, and glutaryl-CoA as potential CoA donors and unequivocally verified the conversion of 3SP to 3SP-CoA. Kinetic studies revealed an apparent Vmax of 44.6 μmol min−1 mg−1 for succinyl-CoA, which corresponds to a turnover number of 36.0 s−1 per subunit of ActTBEA6. For 3SP, the apparent Vmax was determined as 46.8 μmol min−1 mg−1, which corresponds to a turnover number of 37.7 s−1 per subunit of ActTBEA6. The apparent Km values were 0.08 mM for succinyl-CoA and 5.9 mM for 3SP. Nonetheless, the V. paradoxus Δact mutant did not reproduce the phenotype of the Tn5::mob-induced mutant. This defined deletion mutant was able to utilize TDP or 3SP as the sole carbon source, like the wild type. Complementation of the Tn5::mob-induced mutant with pBBR1MCS5::acdDPN7 partially restored growth on 3SP, which indicated a polar effect of the Tn5::mob transposon

  19. Succinyl-CoA:3-sulfinopropionate CoA-transferase from Variovorax paradoxus strain TBEA6, a novel member of the class III coenzyme A (CoA)-transferase family.

    PubMed

    Schürmann, Marc; Hirsch, Beatrice; Wübbeler, Jan Hendrik; Stöveken, Nadine; Steinbüchel, Alexander

    2013-08-01

    The act gene of Variovorax paradoxus TBEA6 encodes a succinyl-CoA:3-sulfinopropionate coenzyme A (CoA)-transferase, Act(TBEA6) (2.8.3.x), which catalyzes the activation of 3-sulfinopropionate (3SP), an intermediate during 3,3'-thiodipropionate (TDP) degradation. In a previous study, accumulation of 3SP was observed in a Tn5::mob-induced mutant defective in growth on TDP. In contrast to the wild type and all other obtained mutants, this mutant showed no growth when 3SP was applied as the sole source of carbon and energy. The transposon Tn5::mob was inserted in a gene showing high homology to class III CoA-transferases. In the present study, analyses of the translation product clearly allocated Act(TBEA6) to this protein family. The predicted secondary structure indicates the lack of a C-terminal α-helix. Act(TBEA6) was heterologously expressed in Escherichia coli Lemo21(DE3) and was then purified by Ni-nitrilotriacetic acid (NTA) affinity chromatography. Analytical size exclusion chromatography revealed a homodimeric structure with a molecular mass of 96 ± 3 kDa. Enzyme assays identified succinyl-CoA, itaconyl-CoA, and glutaryl-CoA as potential CoA donors and unequivocally verified the conversion of 3SP to 3SP-CoA. Kinetic studies revealed an apparent V(max) of 44.6 μmol min(-1) mg(-1) for succinyl-CoA, which corresponds to a turnover number of 36.0 s(-1) per subunit of Act(TBEA6). For 3SP, the apparent V(max) was determined as 46.8 μmol min(-1) mg(-1), which corresponds to a turnover number of 37.7 s(-1) per subunit of Act(TBEA6). The apparent K(m) values were 0.08 mM for succinyl-CoA and 5.9 mM for 3SP. Nonetheless, the V. paradoxus Δact mutant did not reproduce the phenotype of the Tn5::mob-induced mutant. This defined deletion mutant was able to utilize TDP or 3SP as the sole carbon source, like the wild type. Complementation of the Tn5::mob-induced mutant with pBBR1MCS5::acdDPN7 partially restored growth on 3SP, which indicated a polar effect of the Tn5

  20. Effects of fluvastatin and coenzyme Q10 on skeletal muscle in normo- and hypercholesterolaemic rats.

    PubMed

    Vincze, J; Jenes, Á; Füzi, M; Almássy, J; Németh, R; Szigeti, G; Dienes, B; Gaál, Z; Szentesi, P; Jóna, I; Kertai, P; Paragh, G; Csernoch, L

    2015-06-01

    Myalgia and muscle weakness may appreciably contribute to the poor adherence to statin therapy. Although the pathomechanism of statin-induced myopathy is not completely understood, changes in calcium homeostasis and reduced coenzyme Q10 levels are hypothesized to play important roles. In our experiments, fluvastatin and/or coenzyme Q10 was administered chronically to normocholesterolaemic or hypercholaestherolaemic rats, and the modifications of the calcium homeostasis and the strength of their muscles were investigated. While hypercholesterolaemia did not change the frequency of sparks, fluvastatin increased it on muscles both from normocholesterolaemic and from hypercholesterolaemic rats. This effect, however, was not mediated by a chronic modification of the ryanodine receptor as shown by the unchanged ryanodine binding in the latter group. While coenzyme Q10 supplementation significantly reduced the frequency of the spontaneous calcium release events, it did not affect their amplitude and spatial spread in muscles from fluvastatin-treated rats. This indicates that coenzyme Q10 supplementation prevented the spark frequency increasing effect of fluvastatin without having a major effect on the amount of calcium released during individual sparks. In conclusion, we have found that fluvastatin, independently of the cholesterol level in the blood, consistently and specifically increased the frequency of calcium sparks in skeletal muscle cells, an effect which could be prevented by the addition of coenzyme Q10 to the diet. These results support theories favouring the role of calcium handling in the pathophysiology of statin-induced myopathy and provide a possible pathway for the protective effect of coenzyme Q10 in statin treated patients symptomatic of this condition.

  1. Effect of coenzyme Q(10) supplementation on simvastatin-induced myalgia.

    PubMed

    Young, Joanna M; Florkowski, Christopher M; Molyneux, Sarah L; McEwan, Roberta G; Frampton, Christopher M; George, Peter M; Scott, Russell S

    2007-11-01

    Myalgia is the most frequently reported adverse side effect associated with statin therapy and often necessitates reduction in dose, or the cessation of therapy, compromising cardiovascular risk management. One postulated mechanism for statin-related myalgia is mitochondrial dysfunction through the depletion of coenzyme Q(10), a key component of the mitochondrial electron transport chain. This pilot study evaluated the effect of coenzyme Q(10) supplementation on statin tolerance and myalgia in patients with previous statin-related myalgia. Forty-four patients were randomized to coenzyme Q(10) (200 mg/day) or placebo for 12 weeks in combination with upward dose titration of simvastatin from 10 mg/day, doubling every 4 weeks if tolerated to a maximum of 40 mg/day. Patients experiencing significant myalgia reduced their statin dose or discontinued treatment. Myalgia was assessed using a visual analogue scale. There was no difference between combined therapy and statin alone in the myalgia score change (median 6.0 [interquartile range 2.1 to 8.8] vs 2.3 [0 to 12.8], p = 0.63), in the number of patients tolerating simvastatin 40 mg/day (16 of 22 [73%] with coenzyme Q(10) vs 13 of 22 [59%] with placebo, p = 0.34), or in the number of patients remaining on therapy (16 of 22 [73%] with coenzyme Q(10) vs 18 of 22 [82%] with placebo, p = 0.47). In conclusion, coenzyme Q(10) supplementation did not improve statin tolerance or myalgia, although further studies are warranted.

  2. Purification and properties of the membrane-associated coenzyme F420-reducing hydrogenase from Methanobacterium formicicum.

    PubMed Central

    Baron, S F; Ferry, J G

    1989-01-01

    The membrane-associated coenzyme F420-reducing hydrogenase of Methanobacterium formicicum was purified 87-fold to electrophoretic homogeneity. The enzyme contained alpha, beta, and gamma subunits (molecular weights of 43,000, 36,700, and 28,800, respectively) and formed aggregates (molecular weight, 1,020,000) of a coenzyme F420-active alpha 1 beta 1 gamma 1 trimer (molecular weight, 109,000). The hydrogenase contained 1 mol of flavin adenine dinucleotide (FAD), 1 mol of nickel, 12 to 14 mol of iron, and 11 mol of acid-labile sulfide per mol of the 109,000-molecular-weight species, but no selenium. The isoelectric point was 5.6. The amino acid sequence I-N3-P-N2-R-N1-EGH-N6-V (where N is any amino acid) was conserved in the N-termini of the alpha subunits of the F420-hydrogenases from M. formicicum and Methanobacterium thermoautotrophicum and of the largest subunits of nickel-containing hydrogenases from Desulfovibrio baculatus, Desulfovibrio gigas, and Rhodobacter capsulatus. The purified F420-hydrogenase required reductive reactivation before assay. FAD dissociated from the enzyme during reactivation unless potassium salts were present, yielding deflavoenzyme that was unable to reduce coenzyme F420. Maximal coenzyme F420-reducing activity was obtained at 55 degrees C and pH 7.0 to 7.5, and with 0.2 to 0.8 M KCl in the reaction mixture. The enzyme catalyzed H2 production at a rate threefold lower than that for H2 uptake and reduced coenzyme F420, methyl viologen, flavins, and 7,8-didemethyl-8-hydroxy-5-deazariboflavin. Specific antiserum inhibited the coenzyme F420-dependent but not the methyl viologen-dependent activity of the purified enzyme. Images PMID:2738024

  3. Localization of acyl coenzyme A:cholesterol acyltransferase gene to human chromosome 1q25

    SciTech Connect

    Chang, C.C.Y.; Chang, W.; Chang, T.Y. ); Noll, W.W.; Nutile-McMenemy, N. ); Lindsay, E.A.; Baldini, A. )

    1994-01-01

    Acyl coenzyme A:cholesterol acyltransferase (ACAT) is an intracellular enzyme that catalyzes the formation of cholesterol esters from cholesterol and long-chain fatty acyl-coenzyme A. It is believed that ACAT plays a key role in lipoprotein metabolism and atherogenesis. Recently the authors' laboratory succeeded in molecular cloning and functional expression of human macrophage ACAT cDNA. They have now mapped the ACAT gene to chromosome 1, band q25 by using fluorescence in situ hybridization to metaphase chromosomes, and by Southern blotting analysis of human-hamster somatic cell hybrid panels.

  4. Cloning and characterization of the methyl coenzyme M reductase genes from Methanobacterium thermoautotrophicum.

    PubMed Central

    Bokranz, M; Bäumner, G; Allmansberger, R; Ankel-Fuchs, D; Klein, A

    1988-01-01

    The genes coding for methyl coenzyme M reductase were cloned from a genomic library of Methanobacterium thermoautotrophicum Marburg into Escherichia coli by using plasmid expression vectors. When introduced into E. coli, the reductase genes were expressed, yielding polypeptides identical in size to the three known subunits of the isolated enzyme, alpha, beta, and gamma. The polypeptides also reacted with the antibodies raised against the respective enzyme subunits. In M. thermoautotrophicum, the subunits are encoded by a gene cluster whose transcript boundaries were mapped. Sequence analysis revealed two more open reading frames of unknown function located between two of the methyl coenzyme M reductase genes. Images PMID:2448287

  5. Estimation of methanogen biomass via quantitation of coenzyme M

    USGS Publications Warehouse

    Elias, Dwayne A.; Krumholz, Lee R.; Tanner, Ralph S.; Suflita, Joseph M.

    1999-01-01

    Determination of the role of methanogenic bacteria in an anaerobic ecosystem often requires quantitation of the organisms. Because of the extreme oxygen sensitivity of these organisms and the inherent limitations of cultural techniques, an accurate biomass value is very difficult to obtain. We standardized a simple method for estimating methanogen biomass in a variety of environmental matrices. In this procedure we used the thiol biomarker coenzyme M (CoM) (2-mercaptoethanesulfonic acid), which is known to be present in all methanogenic bacteria. A high-performance liquid chromatography-based method for detecting thiols in pore water (A. Vairavamurthy and M. Mopper, Anal. Chim. Acta 78:363–370, 1990) was modified in order to quantify CoM in pure cultures, sediments, and sewage water samples. The identity of the CoM derivative was verified by using liquid chromatography-mass spectroscopy. The assay was linear for CoM amounts ranging from 2 to 2,000 pmol, and the detection limit was 2 pmol of CoM/ml of sample. CoM was not adsorbed to sediments. The methanogens tested contained an average of 19.5 nmol of CoM/mg of protein and 0.39 ± 0.07 fmol of CoM/cell. Environmental samples contained an average of 0.41 ± 0.17 fmol/cell based on most-probable-number estimates. CoM was extracted by using 1% tri-(N)-butylphosphine in isopropanol. More than 90% of the CoM was recovered from pure cultures and environmental samples. We observed no interference from sediments in the CoM recovery process, and the method could be completed aerobically within 3 h. Freezing sediment samples resulted in 46 to 83% decreases in the amounts of detectable CoM, whereas freezing had no effect on the amounts of CoM determined in pure cultures. The method described here provides a quick and relatively simple way to estimate methanogenic biomass.

  6. Coenzyme Q10 reverses mitochondrial dysfunction in atorvastatin-treated mice and increases exercise endurance.

    PubMed

    Muraki, Ayako; Miyashita, Kazutoshi; Mitsuishi, Masanori; Tamaki, Masanori; Tanaka, Kumiko; Itoh, Hiroshi

    2012-08-01

    Statins are cholesterol-lowering drugs widely used in the prevention of cardiovascular diseases; however, they are associated with various types of myopathies. Statins inhibit 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase and thus decrease biosynthesis of low-density lipoprotein cholesterol and may also reduce ubiquinones, essential coenzymes of a mitochondrial electron transport chain, which contain isoprenoid residues, synthesized through an HMG-CoA reductase-dependent pathway. Therefore, we hypothesized that statin treatment might influence physical performance through muscular mitochondrial dysfunction due to ubiquinone deficiency. The effect of two statins, atorvastatin and pravastatin, on ubiquinone content, mitochondrial function, and physical performance was examined by using statin-treated mice. Changes in energy metabolism in association with statin treatment were studied by using cultured myocytes. We found that atorvastatin-treated mice developed muscular mitochondrial dysfunction due to ubiquinone deficiency and a decrease in exercise endurance without affecting muscle mass and strength. Meanwhile, pravastatin at ten times higher dose of atorvastatin had no such effects. In cultured myocytes, atorvastatin-related decrease in mitochondrial activity led to a decrease in oxygen utilization and an increase in lactate production. Conversely, coenzyme Q(10) treatment in atorvastatin-treated mice reversed atorvastatin-related mitochondrial dysfunction and a decrease in oxygen utilization, and thus improved exercise endurance. Atorvastatin decreased exercise endurance in mice through mitochondrial dysfunction due to ubiquinone deficiency. Ubiquinone supplementation with coenzyme Q(10) could reverse atorvastatin-related mitochondrial dysfunction and decrease in exercise tolerance.

  7. Structural insights into substrate and coenzyme preference by SDR family protein Gox2253 from Gluconobater oxydans.

    PubMed

    Yin, Bo; Cui, Dongbing; Zhang, Lujia; Jiang, Shuiqin; Machida, Satoru; Yuan, Y Adam; Wei, Dongzhi

    2014-11-01

    Gox2253 from Gluconobacter oxydans belongs to the short-chain dehydrogenases/reductases family, and catalyzes the reduction of heptanal, octanal, nonanal, and decanal with NADPH. To develop a robust working platform to engineer novel G. oxydans oxidoreductases with designed coenzyme preference, we adopted a structure based rational design strategy using computational predictions that considers the number of hydrogen bonds formed between enzyme and docked coenzyme. We report the crystal structure of Gox2253 at 2.6 Å resolution, ternary models of Gox2253 mutants in complex with NADH/short-chain aldehydes, and propose a structural mechanism of substrate selection. Molecular dynamics simulation shows that hydrogen bonds could form between 2'-hydroxyl group in the adenosine moiety of NADH and the side chain of Gox2253 mutant after arginine at position 42 is replaced with tyrosine or lysine. Consistent with the molecular dynamics prediction, Gox2253-R42Y/K mutants can use both NADH and NADPH as a coenzyme. Hence, the strategies here could provide a practical platform to engineer coenzyme selectivity for any given oxidoreductase and could serve as an additional consideration to engineer substrate-binding pockets.

  8. The transient catalytically competent coenzyme allocation into the active site of Anabaena ferredoxin NADP+ -reductase.

    PubMed

    Peregrina, José Ramón; Lans, Isaías; Medina, Milagros

    2012-01-01

    Ferredoxin-NADP(+) reductase (FNR) catalyses the electron transfer from ferredoxin to NADP(+) via its flavin FAD cofactor. A molecular dynamics theoretical approach is applied here to visualise the transient catalytically competent interaction of Anabaena FNR with its coenzyme, NADP(+). The particular role of some of the residues identified as key in binding and accommodating the 2'P-AMP moiety of the coenzyme is confirmed in molecular terms. Simulations also indicate that the architecture of the active site precisely contributes to the orientation of the N5 of the FAD isoalloxazine ring and the C4 of the coenzyme nicotinamide ring in the conformation of the catalytically competent hydride transfer complex and, therefore, contributes to the efficiency of the process. In particular, the side chain of the C-terminal Y303 in Anabaena FNR appears key to providing the optimum geometry by reducing the stacking probability between the isoalloxazine and nicotinamide rings, thus providing the required co-linearity and distance among the N5 of the flavin cofactor, the C4 of the coenzyme nicotinamide and the hydride that has to be transferred between them. All these factors are highly related to the reaction efficiency, mechanism and reversibility of the process.

  9. Aldose and aldehyde reductases : structure-function studies on the coenzyme and inhibitor-binding sites.

    SciTech Connect

    El-Kabbani, O.; Old, S. E.; Ginell, S. L.; Carper, D. A.; Biosciences Division; Monash Univ.; NIH

    1999-09-03

    PURPOSE: To identify the structural features responsible for the differences in coenzyme and inhibitor specificities of aldose and aldehyde reductases. METHODS: The crystal structure of porcine aldehyde reductase in complex with NADPH and the aldose reductase inhibitor sorbinil was determined. The contribution of each amino acid lining the coenzyme-binding site to the binding of NADPH was calculated using the Discover package. In human aldose reductase, the role of the non-conserved Pro 216 (Ser in aldehyde reductase) in the binding of coenzyme was examined by site-directed mutagenesis. RESULTS: Sorbinil binds to the active site of aldehyde reductase and is hydrogen-bonded to Trp 22, Tyr 50, His 113, and the non-conserved Arg 312. Unlike tolrestat, the binding of sorbinil does not induce a change in the side chain conformation of Arg 312. Mutation of Pro 216 to Ser in aldose reductase makes the binding of coenzyme more similar to that of aldehyde reductase. CONCLUSIONS: The participation of non-conserved active site residues in the binding of inhibitors and the differences in the structural changes required for the binding to occur are responsible for the differences in the potency of inhibition of aldose and aldehyde reductases. We report that the non-conserved Pro 216 in aldose reductase contributes to the tight binding of NADPH.

  10. Nano-encapsulation of coenzyme Q10 using octenyl succinic anhydride modified starch

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Octenyl succinic anhydride modified starch (OSA-ST) was used to encapsulate Coenzyme Q10 (CoQ10). CoQ10 was dissolved in rice bran oil (RBO), and incorporated into an aqueous OSA-ST solution. High pressure homogenization (HPH) of the mixture was conducted at 170 MPa for 5-6 cycles. The resulting ...

  11. Synthesis of coenzyme A thioesters using methyl acyl phosphates in an aqueous medium.

    PubMed

    Pal, Mohan; Bearne, Stephen L

    2014-12-28

    Regioselective S-acylation of coenzyme A (CoA) is achieved under aqueous conditions using various aliphatic and aromatic carboxylic acids activated as their methyl acyl phosphate monoesters. Unlike many hydrophobic activating groups, the anionic methyl acyl phosphate mixed anhydride is more compatible with aqueous solvents, making it useful for conducting acylation reactions in an aqueous medium.

  12. Kinetic and spectral investigation of allosteric interaction of coenzymes with 2-oxo acid dehydrogenase complexes

    NASA Astrophysics Data System (ADS)

    Strumiło, S.; Czygier, M.; Kondracikowska, J.; Dobrzyń, P.; Czerniecki, J.

    2002-09-01

    The possible role of thiamine pyrophosphate (TPP) in the regulation of both multienzyme pyruvate dehydrogenase complex (PDC) and 2-oxoglutarate dehydrogenase complex (OGDC) has been investigated by kinetic and spectral methods. The purified PDC and OGDC from animal heart muscle were near saturated with endogenous TPP. The PDC containing the bound coenzyme showed hysteretic behaviour manifested in a lag phase of the catalysed reaction after the contact of PDC with substrates. Exogenous TPP added to the full reaction medium led to a disappearance of the lag phase and to strong reduction of the Michaelis constant ( Km) value for pyruvate, and more moderate decrease of Km for both coenzyme A and NAD. In the case of OGDC exogenous TPP also decreased S 0.5 ( Km) for substrate 2-oxoglutarate. In addition, exogenous TPP changed both the UV and circular dichroism spectra of PDC and last one of OGDC, and lowered the fluorescence emission of the multienzyme complexes containing bound molecules of endogenous coenzyme in their active sites. Thiamine pyrophosphate seems to play, besides its coenzyme function, the role of positive allosteric effector which causes conformational changes of the multienzyme complexes and increases their affinity to substrates.

  13. A possible prebiotic synthesis of pantetheine, a precursor to coenzyme A

    NASA Technical Reports Server (NTRS)

    Keefe, A. D.; Newton, G. L.; Miller, S. L.

    1995-01-01

    The involvement of coenzyme A in many enzyme reactions suggests that it acted in this capacity very early in the development of life on Earth. Particularly relevant in this regard is its role in the activation of amino acids and hydroxy acids in the biosynthesis of some peptide antibiotics--a mechanism of peptide synthesis that forms the basis for the proposal that a thioester world could have preceded the RNA world. The components of coenzyme A have been shown to be probable prebiotic compounds: beta-alanine, pantoyl lactone and cysteamine and possibly adenosine. We show here that the pantetheine moiety of coenzyme A (which also occurs in a number of enzymes) can be synthesized in yields of several per cent by heating pantoyl lactone, beta-alanine and cysteamine at temperatures as low as 40 degrees C. These components are extremely soluble and so would have been preferentially concentrated in evaporating bodies of water, for example on beaches and at lagoon margins. Our results show that amide bonds can be formed at temperatures as low as 40 degrees C, and provide circumstantial support for the suggestion that pantetheine and coenzyme A were important in the earliest metabolic systems.

  14. Modifications of plasma proteome in long-lived rats fed on a coenzyme Q10-supplemented diet.

    PubMed

    Santos-González, Mónica; Gómez Díaz, Consuelo; Navas, Plácido; Villalba, José Manuel

    2007-08-01

    Dietary coenzyme Q(10) prolongs life span of rats fed on a PUFAn-6-enriched diet. Our aim was to analyze changes in the levels of plasma proteins of rats fed on a PUFAn-6 plus coenzyme Q(10)-based diet. This approach could give novel insights into the mechanisms of life span extension by dietary coenzyme Q(10) in the rat. Serum albumin, which decreases with aging in the rat, was significantly increased by coenzyme Q(10) supplementation both at 6 and 24 months. After depletion of the most abundant proteins by affinity chromatography, levels of less abundant plasma proteins were also studied by using 2D-electrophoresis and MALDI-TOF mass fingerprinting analysis. Our results have shown that lifelong dietary supplementation with coenzyme Q(10) induced significant decreases of plasma hemopexin, apolipoprotein H and inter-alpha-inhibitor H4P heavy chain (at both 6 and 24 months), preprohaptoglobin, fibrinogen gamma-chain precursor, and fetuin-like protein (at 6 months), and alpha-1-antitrypsin precursor and type II peroxiredoxin (at 24 months). On the other hand, coenzyme Q(10) supplementation resulted in significant increases of serine protease inhibitor 3, vitamin D-binding protein (at 6 months), and Apo A-I (at 24 months). Our results support a beneficial role of dietary coenzyme Q(10) decreasing oxidative stress and cardiovascular risk, and modulating inflammation during aging.

  15. Characterization of the enzymatic conversion of sulfoacetaldehyde and L-cysteine into coenzyme M (2-mercaptoethanesulfonic acid)

    SciTech Connect

    White, R.H. )

    1988-09-20

    Sulfoacetaldehyde was shown to be converted enzymatically into coenzyme M by cell-free extracts of methanogenic bacteria. Gas chromatography-mass spectrometry (GC-MS) of the S-methyl methyl ester derivative of the coenzyme M isolated from the extracts was used to measure both the extent and position of the deuterium incorporated into coenzyme M from (2,2-{sup 2}H{sub 2})sulfoacetaldehyde. The conversion of sulfoacetaldehyde into coenzyme M was greatly stimulated by the addition of L-cysteine (20 mM) to the extracts and/or by incubating the extracts under hydrogen, whereas incubation in the presence of sulfide (20 mM) greatly reduced coenzyme M synthesis. Incubation of a cell-free extract from Methanobacterium formicicum with (2,2-{sup 2}H{sub 2})sulfoacetaldehyde and ({sup 34}S)-L-cysteine (92.6 atom % {sup 34}S) led to the production of coenzyme M in which the thiol portion of the molecule contained 90 atom % {sup 34}S. (ethylene-{sup 2}H{sub 4})-S-(2-Sulfoethyl)cysteine, incubated with this cell-free extract at a concentration of 22 mM, readily cleaved to coenzyme M. On the basis of these observations, it is concluded that sulfoacetaldehyde is converted into coenzyme M by reacting with cysteine to form the thiazolidine adduct (2-(sulfomethyl)thiazolidine-4-carboxylic acid), which undergoes a reductive cleavage of the heterocyclic C(2)-N bond to form S-(2-sulfoethyl)cysteine, which, in turn, undergoes a {beta}-elimination to produce coenzyme M.

  16. Detection of organometallic and radical intermediates in the catalytic mechanism of methyl-coenzyme M reductase using the natural substrate methyl-coenzyme M and a coenzyme B substrate analogue.

    PubMed

    Dey, Mishtu; Li, Xianghui; Kunz, Ryan C; Ragsdale, Stephen W

    2010-12-28

    Methyl-coenzyme M reductase (MCR) from methanogenic archaea catalyzes the terminal step in methanogenesis using coenzyme B (CoBSH) as the two-electron donor to reduce methyl-coenzyme M (methyl-SCoM) to form methane and the heterodisulfide, CoBS-SCoM. The active site of MCR contains an essential redox-active nickel tetrapyrrole cofactor, coenzyme F(430), which is active in the Ni(I) state (MCR(red1)). Several catalytic mechanisms have been proposed for methane synthesis that mainly differ in whether an organometallic methyl-Ni(III) or a methyl radical is the first catalytic intermediate. A mechanism was recently proposed in which methyl-Ni(III) undergoes homolysis to generate a methyl radical (Li, X., Telser, J., Kunz, R. C., Hoffman, B. M., Gerfen, G., and Ragsdale, S. W. (2010) Biochemistry 49, 6866-6876). Discrimination among these mechanisms requires identification of the proposed intermediates, none of which have been observed with native substrates. Apparently, intermediates form and decay too rapidly to accumulate to detectible amounts during the reaction between methyl-SCoM and CoBSH. Here, we describe the reaction of methyl-SCoM with a substrate analogue (CoB(6)SH) in which the seven-carbon heptanoyl moiety of CoBSH has been replaced with a hexanoyl group. When MCR(red1) is reacted with methyl-SCoM and CoB(6)SH, methanogenesis occurs 1000-fold more slowly than with CoBSH. By transient kinetic methods, we observe decay of the active Ni(I) state coupled to formation and subsequent decay of alkyl-Ni(III) and organic radical intermediates at catalytically competent rates. The kinetic data also revealed substrate-triggered conformational changes in active Ni(I)-MCR(red1). Electron paramagnetic resonance (EPR) studies coupled with isotope labeling experiments demonstrate that the radical intermediate is not tyrosine-based. These observations provide support for a mechanism for MCR that involves methyl-Ni(III) and an organic radical as catalytic intermediates

  17. A STD-NMR study of the interaction of the Anabaena ferredoxin-NADP+ reductase with the coenzyme.

    PubMed

    Antonini, Lara V; Peregrina, José R; Angulo, Jesús; Medina, Milagros; Nieto, Pedro M

    2014-01-07

    Ferredoxin-NADP+ reductase (FNR) catalyzes the electron transfer from ferredoxin to NADP+ via its flavin FAD cofactor. To get further insights in the architecture of the transient complexes produced during the hydride transfer event between the enzyme and the NADP+ coenzyme we have applied NMR spectroscopy using Saturation Transfer Difference (STD) techniques to analyze the interaction between FNRox and the oxidized state of its NADP+ coenzyme. We have found that STD NMR, together with the use of selected mutations on FNR and of the non-FNR reacting coenzyme analogue NAD+, are appropriate tools to provide further information about the the interaction epitope.

  18. Coenzyme autocatalytic network on the surface of oil microspheres as a model for the origin of life.

    PubMed

    Sharov, Alexei A

    2009-04-22

    Coenzymes are often considered as remnants of primordial metabolism, but not as hereditary molecules. I suggest that coenzyme-like molecules (CLMs) performed hereditary functions before the emergence of nucleic acids. Autocatalytic CLMs modified (encoded) surface properties of hydrocarbon microspheres, to which they were anchored, and these changes enhanced autocatalysis and propagation of CLMs. Heredity started from a single kind of self-reproducing CLM, and then evolved into more complex coenzyme autocatalytic networks containing multiple kinds of CLMs. Polymerization of CLMs on the surface of microspheres and development of template-based synthesis is a potential evolutionary path towards the emergence of nucleic acids.

  19. Coenzyme Autocatalytic Network on the Surface of Oil Microspheres as a Model for the Origin of Life

    PubMed Central

    Sharov, Alexei A.

    2009-01-01

    Coenzymes are often considered as remnants of primordial metabolism, but not as hereditary molecules. I suggest that coenzyme-like molecules (CLMs) performed hereditary functions before the emergence of nucleic acids. Autocatalytic CLMs modified (encoded) surface properties of hydrocarbon microspheres, to which they were anchored, and these changes enhanced autocatalysis and propagation of CLMs. Heredity started from a single kind of self-reproducing CLM, and then evolved into more complex coenzyme autocatalytic networks containing multiple kinds of CLMs. Polymerization of CLMs on the surface of microspheres and development of template-based synthesis is a potential evolutionary path towards the emergence of nucleic acids. PMID:19468342

  20. Coenzyme M derivatives and their effects on methane formation from carbon dioxide and methanol by cell extracts of Methanosarcina barkeri.

    PubMed Central

    Hutten, T J; De Jong, M H; Peeters, B P; van der Drift, C; Vogels, G D

    1981-01-01

    Extracts of Methanosarcina barkeri reduced methanol and CO2 to CH4 in the presence of H2 and converted methanol stoichiometrically into CH4 and CO2 in the absence of H2. In dialyzed cell-free extracts these reactions were stimulated by 2-mercaptoethanesulfonic acid (coenzyme M) and some derivatives (acetyl and formylcoenzyme M and the oxidized form of coenzyme M), which could be converted to coenzyme M by enzyme systems present in the extracts. Methylcoenzyme M could not be used in these systems. PMID:6780512

  1. Biochemical characterization of a Rhizobium etli monovalent cation-stimulated acyl-coenzyme A carboxylase with a high substrate specificity constant for propionyl-coenzyme A.

    PubMed

    Dunn, Michael F; Araíza, Gisela; Mora, Jaime

    2004-02-01

    Biotin has a profound effect on the metabolism of rhizobia. It is reported here that the activities of the biotin-dependent enzymes acetyl-coenzyme A carboxylase (ACC; EC 6.4.1.2) and propionyl-coenzyme A carboxylase (PCC; EC 6.4.1.3) are present in all species of the five genera comprising the Rhizobiaceae which were examined. Evidence is presented that the ACC and PCC activities detectable in Rhizobium etli extracts are catalysed by a single acyl-coenzyme A carboxylase. The enzyme from R. etli strain 12-53 was purified 478-fold and displayed its highest activity with propionyl-CoA as substrate, with apparent K(m) and V(max) values of 0.064 mM and 2885 nmol min(-1) (mg protein)(-1), respectively. The enzyme carboxylated acetyl-CoA and butyryl-CoA with apparent K(m) values of 0.392 and 0.144 mM, respectively, and V(max) values of 423 and 268 nmol min(-1) (mg protein)(-1), respectively. K(+), or Cs(+) markedly activated the enzyme, which was essentially inactive in their absence. Electrophoretic analysis indicated that the acyl-CoA carboxylase was composed of a 74 kDa biotin-containing alpha subunit and a 45 kDa biotin-free beta subunit, and gel chromatography indicated a total molecular mass of 620 000 Da. The strong kinetic preference of the enzyme for propionyl-CoA is consistent with its participation in an anaplerotic pathway utilizing this substrate.

  2. Coenzyme Q10 supplementation in infertile men with low-grade varicocele: an open, uncontrolled pilot study.

    PubMed

    Festa, R; Giacchi, E; Raimondo, S; Tiano, L; Zuccarelli, P; Silvestrini, A; Meucci, E; Littarru, G P; Mancini, A

    2014-09-01

    Many conditions associated with male infertility are inducers of oxidative stress, including varicocele. Antioxidants, such as coenzyme Q10, may be useful in this case. To evaluate the antioxidant capacity of seminal plasma of infertile men with varicocele before and after an oral supplementation with coenzyme Q10 , 38 patients were recruited from a pilot clinical trial. A standard semen analysis was also performed at baseline and 3 months after an oral supplementation with exogenous coenzyme Q10 100 mg per die. Seminal plasma antioxidant capacity was measured using a spectroscopic method. Coenzyme Q10 therapy improved semen parameters and antioxidant status. This study highlights the importance of oxidative stress in the pathogenesis of male infertility, namely in varicocele, and strengthens the possibility of the usefulness of the antioxidant therapy.

  3. Reversal of coenzyme specificity and improvement of catalytic efficiency of Pichia stipitis xylose reductase by rational site-directed mutagenesis.

    PubMed

    Zeng, Qi-Kai; Du, Hong-Li; Wang, Jing-Fang; Wei, Dong-Qing; Wang, Xiao-Ning; Li, Yi-Xue; Lin, Ying

    2009-07-01

    A major problem when xylose is used for ethanol production is the intercellular redox imbalance arising from different coenzyme specificities of xylose reductase (XR) and xylitol dehydrogenase. The residue Lys21 in XR from Pichia stipitis was subjected to site-directed mutagenesis to alter its coenzyme specificity. The N272D mutant exhibited improved catalytic efficiency when NADH was the coenzyme. Both K21A and K21A/N272D preferred NADH to NADPH, their catalytic efficiencies for NADPH were almost zero. The catalytic efficiency of K21A/N272D for NADH was almost 9-fold and 2-fold that of K21A and the wild-type enzyme, respectively. Complete reversal of coenzyme specificity toward NADH and improved catalytic efficiency were achieved.

  4. Complex-1 activity and 18F-DOPA uptake in genetically engineered mouse model of Parkinson's disease and the neuroprotective role of coenzyme Q10.

    PubMed

    Sharma, Sushil K; El Refaey, Hesham; Ebadi, Manuchair

    2006-06-15

    Regional distribution of coenzyme Q10 and mitochondrial complex-1 activity were estimated in the brains of control-(C57BL/6), metallothionein knock out-, metallothionein transgenic-, and homozygous weaver mutant mice; and human dopaminergic (SK-N-SH) cells with a primary objective to determine the neuroprotective potential of coenzyme Q10 in Parkinson's disease. Complex-1 activity as well as coenzyme Q10 were significantly higher in the cerebral cortex as compared to the striatum in all the genotypes examined. Complex-1 activity and coenzyme Q10 were significantly reduced in weaver mutant mice and metallothionein knock out mice, but were significantly increased in metallothionein transgenic mice. The reduced complex-1 activity and 18F-DOPA uptake occurred concomitantly with negligible differences in the coenzyme Q10 between in the cerebral cortex and striatum of weaver mutant mice. Administration of coenzyme Q10 increased complex-1 activity and partially improved motoric performance in weaver mutant mice. Direct exposure of rotenone also reduced coenzyme Q10, complex-1 activity, and mitochondrial membrane potential in SK-N-SH cells. Rotenone-induced down-regulation of complex-1 activity was attenuated by coenzyme Q10 treatment, suggesting that complex-1 may be down regulated due to depletion of coenzyme Q10 in the brain. Therefore, metallothionein-induced coenzyme Q10 synthesis may provide neuroprotection by augmenting mitochondrial complex-1 activity in Parkinson's disease.

  5. Elucidation of molecular mechanism involved in neuroprotective effect of Coenzyme Q10 in alcohol-induced neuropathic pain.

    PubMed

    Kandhare, Amit D; Ghosh, Pinaki; Ghule, Arvindkumar E; Bodhankar, Subhash L

    2013-12-01

    The aim of the present investigation was to evaluate the effect of Coenzyme Q10 and its combination with vitamin E in alcohol-induced chronic neuropathic pain. Male Wistar rats were orally treated with alcohol (10 g/kg, 35% v/v, b.i.d.) for 10 weeks. Coenzyme Q10 (25, 50, and 100 mg/kg) and vitamin E (100 mg/kg) were coadministered orally for 1 h after ethanol administration for 10 weeks. Various nerve functions, biochemical, and molecular parameters were assessed. Chronic administration of ethanol for 10 weeks resulted significant development of neuropathic pain. Treatment with Coenzyme Q10 (50 and 100 mg/kg) for 10 weeks showed significant and dose dependently increased in level of nociceptive threshold, endogenous antioxidant, and Na,K-ATPase enzyme. Coenzyme Q10 (50 and 100 mg/kg) significantly restored the levels of motor nerve conduction velocity and sensory nerve conduction velocity. It also showed significant decrease in levels of endogenous calcium, oxidative-nitrosative stress, TNF-α, IL-1β, and IL-4 level. Alteration in protein expression of polymerase gamma (pol γ) was significantly restored the Coenzyme Q10 treatment. The important finding of the study is that, Coenzyme Q10 (100 mg/kg) and α-tocopherol (100 mg/kg) combination-treated rats showed more significant prevention of behavioral, biochemical, and molecular neurotoxic effect of alcohol administration than Coenzyme Q10 or α-tocopherol alone treated group. It is evident from the finding of present investigation that plethora of mechanism including inhibition of oxido-nitrosative stress, release of pro-inflammatory cytokine, modulation of endogenous biomarker, and protection of pol γ protein expression simultaneously orchestrate to exhibits neuroprotective effect of Coenzyme Q10, vitamin E and their combination.

  6. Amelioration of altered antioxidant enzymes activity and glomerulosclerosis by coenzyme Q10 in alloxan-induced diabetic rats.

    PubMed

    Ahmadvand, Hassan; Tavafi, Majid; Khosrowbeygi, Ali

    2012-01-01

    Coenzyme Q10 is a natural antioxidant and scavenging free radicals. In the present study, we examined antioxidative activities of coenzyme Q10 and possible protective effect of coenzyme Q10 on in vivo and in vitro lipid peroxidation, antioxidant enzymes activity and glomerulosclerosis in alloxan-induced type 1 diabetic rats. Thirty Sprague-Dawley male rats were divided into three groups randomly: group 1 as control, group 2 as diabetic untreatment, and group 3 as treatments with coenzyme Q10 by 15 mg/kg i.p. daily, respectively. Diabetes was induced in the second and third groups by alloxan injection subcutaneously. After 8 weeks, animals were anaesthetized, liver and kidney were then removed immediately and used fresh or kept frozen until their lipid peroxidation analysis. Blood samples were also collected before killing to measure the lipid peroxidation and antioxidant enzymes activity. Kidney paraffin sections were prepared and stained by periodic acid-Schiff method. Glomerular volume and leukocyte infiltration were estimated by stereological rules and glomerular sclerosis was studied semi-quantitatively. Coenzyme Q10 significantly inhibited leukocyte infiltration, glomerulosclerosis and the levels of malondialdehyde (MDA) serum and kidney content in treated group compared with the diabetic untreated group. Coenzyme Q10 significantly inhibited LDL oxidation in vitro. Coenzyme Q10 significantly increased the serum levels of glutathione (GSH) and serum activity of catalase (CAT) and superoxide dismutase (SOD) in treated group compared with the diabetic untreated group. Coenzyme Q10 alleviates leukocyte infiltration and glomerulosclerosis and exerts beneficial effects on the lipid peroxidation and antioxidant enzymes activity in alloxan-induced type 1 diabetic rats.

  7. Conserved catalytic residues of the ALDH1L1 aldehyde dehydrogenase domain control binding and discharging of the coenzyme.

    PubMed

    Tsybovsky, Yaroslav; Krupenko, Sergey A

    2011-07-01

    The C-terminal domain (C(t)-FDH) of 10-formyltetrahydrofolate dehydrogenase (FDH, ALDH1L1) is an NADP(+)-dependent oxidoreductase and a structural and functional homolog of aldehyde dehydrogenases. Here we report the crystal structures of several C(t)-FDH mutants in which two essential catalytic residues adjacent to the nicotinamide ring of bound NADP(+), Cys-707 and Glu-673, were replaced separately or simultaneously. The replacement of the glutamate with an alanine causes irreversible binding of the coenzyme without any noticeable conformational changes in the vicinity of the nicotinamide ring. Additional replacement of cysteine 707 with an alanine (E673A/C707A double mutant) did not affect this irreversible binding indicating that the lack of the glutamate is solely responsible for the enhanced interaction between the enzyme and the coenzyme. The substitution of the cysteine with an alanine did not affect binding of NADP(+) but resulted in the enzyme lacking the ability to differentiate between the oxidized and reduced coenzyme: unlike the wild-type C(t)-FDH/NADPH complex, in the C707A mutant the position of NADPH is identical to the position of NADP(+) with the nicotinamide ring well ordered within the catalytic center. Thus, whereas the glutamate restricts the affinity for the coenzyme, the cysteine is the sensor of the coenzyme redox state. These conclusions were confirmed by coenzyme binding experiments. Our study further suggests that the binding of the coenzyme is additionally controlled by a long-range communication between the catalytic center and the coenzyme-binding domain and points toward an α-helix involved in the adenine moiety binding as a participant of this communication.

  8. Involvement of the pyrophosphate and the 2'-phosphate binding regions of ferredoxin-NADP+ reductase in coenzyme specificity.

    PubMed

    Tejero, Jesús; Martínez-Julvez, Marta; Mayoral, Tomas; Luquita, Alejandra; Sanz-Aparicio, Julia; Hermoso, Juan A; Hurley, John K; Tollin, Gordon; Gómez-Moreno, Carlos; Medina, Milagros

    2003-12-05

    Previous studies indicated that the determinants of coenzyme specificity in ferredoxin-NADP+ reductase (FNR) from Anabaena are situated in the 2'-phosphate (2'-P) NADP+ binding region, and also suggested that other regions must undergo structural rearrangements of the protein backbone during coenzyme binding. Among the residues involved in such specificity could be those located in regions where interaction with the pyrophosphate group of the coenzyme takes place, namely loops 155-160 and 261-268 in Anabaena FNR. In order to learn more about the coenzyme specificity determinants, and to better define the structural basis of coenzyme binding, mutations in the pyrophosphate and 2'-P binding regions of FNR have been introduced. Modification of the pyrophosphate binding region, involving residues Thr-155, Ala-160, and Leu-263, indicates that this region is involved in determining coenzyme specificity and that selected alterations of these positions produce FNR enzymes that are able to bind NAD+. Thus, our results suggest that slightly different structural rearrangements of the backbone chain in the pyrophosphate binding region might determine FNR specificity for the coenzyme. Combined mutations at the 2'-P binding region, involving residues Ser-223, Arg-224, Arg-233, and Tyr-235, in combination with the residues mentioned above in the pyrophosphate binding region have also been carried out in an attempt to increase the FNR affinity for NAD+/H. However, in most cases the analyzed mutants lost the ability for NADP+/H binding and electron transfer, and no major improvements were observed with regard to the efficiency of the reactions with NAD+/H. Therefore, our results confirm that determinants for coenzyme specificity in FNR are also situated in the pyrophosphate binding region and not only in the 2'-P binding region. Such observations also suggest that other regions of the protein, yet to be identified, might also be involved in this process.

  9. Protective effects of coenzyme Q10 against angiotensin II-induced oxidative stress in human umbilical vein endothelial cells.

    PubMed

    Tsuneki, Hiroshi; Tokai, Emi; Suzuki, Takashi; Seki, Takayuki; Okubo, Kyosuke; Wada, Tsutomu; Okamoto, Tadashi; Koya, Sakuji; Kimura, Ikuko; Sasaoka, Toshiyasu

    2013-02-15

    Angiotensin II is the major effector in the renin-angiotensin system, and angiotensin II-induced oxidative stress and endothelial dysfunction are profoundly implicated in the pathogenesis of hypertension and cardiovascular disease. In the present study, we investigated the effect of an antioxidant reagent, coenzyme Q10, on angiotensin II-induced oxidative stress in human umbilical vein endothelial cells (HUVEC) to assess its potential usefulness for antioxidant therapy. Treatment of HUVEC with coenzyme Q10 (1-10μM) increased its intracellular levels in a concentration-dependent manner. Coenzyme Q10 (10μM) prevented the actions of angiotensin II (100nM): overproduction of reactive oxygen species, increases in expression of p22(phox) and Nox2 subunits of NADPH oxidase, and inhibition of insulin-induced nitric oxide production. In addition, coenzyme Q10 prevented angiotensin II-induced upregulation of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in HUVEC, and inhibited their adhesion to U937 monocytic cells. Moreover, treatment of HUVEC with coenzyme Q10 effectively ameliorated angiotensin II-induced increases in expression of Nox2 subunit of NADPH oxidase, ICAM-1, and VCAM-1. These results provide the first in vitro evidence that coenzyme Q10 is an efficient antioxidant reagent to improve angiotensin II-induced oxidative stress and endothelial dysfunction, possibly relevant to the causes of cardiovascular disease.

  10. Ni/sup II/(dioxo(16)aneN/sub 5/)-induced methane formation from methyl coenzyme M

    SciTech Connect

    Drain, C.M.; Sable, D.B.; Corden, B.B.

    1988-07-13

    A mechanism has been previously proposed for methyl-coenzyme M (H/sub 3/CSCH/sub 2/CH/sub 2/SO/sub 3//sup /minus//) reductase where Ni/sup II/F/sub 430/ is first reduced to NiF/sub 430/, which homolytically cleaves the methyl-coenzyme M to produce methyl-Ni/sup I/F/sub 430/ followed by the protonation of methyl-Ni/sup I/F/sub 430/ to yield CH/sub 4/ and Ni/sup II/F/sub 430/. The role of the nickel ion oxidation state in methyl-coenzyme M catalysis has been examined. It was found that both the mono- and divalent oxidation states of the water soluble Ni (dioxo(16)-aneN/sub 5/), NiL, complex catalyze the methyl-coenzyme M to methane and coenzyme M. Some aqueous solutions of other nickel compounds, e.g. nickel (II) acetate, nickel(II) tetraethylenepentamine, or nickel(II) 1,4,8,11-tetraazacyclotetradecane-5,7-dione, do not convert methyl-coenzyme M to methane under argon or hydrogen. 30 references, 1 figure.

  11. Bipartite recognition and conformational sampling mechanisms for hydride transfer from nicotinamide coenzyme to FMN in pentaerythritol tetranitrate reductase.

    PubMed

    Pudney, Christopher R; Hay, Sam; Scrutton, Nigel S

    2009-09-01

    Elucidating the origin of substrate and coenzyme specificity has been the focus of much work relating to enzyme engineering. Many enzymes exhibit tight specificity for particular substrates despite a close structural relationship to other nonreactive compounds. This tight specificity is especially remarkable and important biologically for the coenzymes NADH and NADPH. In the present study, we examined the preference of pentaerythritol tetranitrate reductase, an 'old yellow enzyme' family member, for the coenzymes NADPH over NADH. Using structural and mutagenesis studies, we have previously established that the coenzyme nicotinamide group is the key binding determinant in old yellow enzymes [Khan H et al. (2005) FEBS J 272, 4660-4671]. We have now performed detailed transient-state studies using NAD(P)H and the nonreactive analogues 1,4,5,6-tetrahydroNAD(P)H [NAD(P)H4], leading us to uncover an additional binding step in the reductive half-reaction of pentaerythritol tetranitrate reductase. We suggest that this initial binding step may primarily reflect binding of the adenine ribophosphate portion of the coenzyme, and that the second step reflects a rearrangement of the nicotinamide. Bipartite recognition, in which the adenine ribophosphate moiety localizes the coenzyme in the active site region, enables subsequent and localized searches of configurational space by the nicotinamide moiety to form the catalytically relevant charge-transfer complex. We suggest that this localized search contributes to catalytic efficiency via the principle of 'reduction in dimensionality'.

  12. Correlation between vitamin A, E, coenzyme Q10 and degree of insulin resistance in obese and non-obese subjects

    PubMed Central

    Mehmetoglu, Idris; Yerlikaya, F. Hümeyra; Kurban, Sevil

    2011-01-01

    The aim of the present study was to investigate correlation between plasma vitamin A, vitamin E, serum coenzyme Q10 levels and degree of insulin resistance in obese and normal weight people. The study was performed on 98 (21 Male, 77 Female) obese people and 78 (20 Male, 58 Female) control subjects. Vitamin A, E and coenzyme Q10 levels were adjusted to the lipid levels. Adjusted vitamin A and E and coenzyme Q10 levels of the obese female group were significantly lower than those of the control female group. Adjusted vitamin A and coenzyme Q10 levels of the obese male group were significantly lower than those of the control male group. Insulin resistance level of the obese female and male groups were significantly higher than that of the control female and male groups. There were no significant correlations between serum coenzyme Q10, plasma vitamin A and E levels and insulin resistance in obese and control subjects. Our findings show that it is essential to use the lipid adjusted levels of lipid soluble nutrients in obesity. Also, we have found no association between insulin resistance and vitamin A, vitamin E and coenzyme Q10 levels in obese subjects. PMID:22128213

  13. Short- and long-term regulation of 3-hydroxy 3-methylglutaryl coenzyme A reductase by a 4-methylcoumarin.

    PubMed

    Trapani, Laura; Segatto, Marco; Simeoni, Veronica; Balducci, Valentina; Dhawan, Ashish; Parmar, Virinder S; Prasad, Ashok K; Saso, Luciano; Incerpi, Sandra; Pallottini, Valentina

    2011-07-01

    Dyslipidemia is one of the most significant risk factors for cardiovascular diseases. Cholesterol homeostasis is regulated by both the receptor-mediated endocytosis of Low Density Lipoproteins by LDL receptors and de novo cholesterol synthesis via the rate-limiting enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase. Although statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase substrate competitors, have revolutionized the management of cardiovascular diseases by lowering serum LDL, their side effects range from myalgia to rhabdomyolysis. Treatment with antioxidant compounds could represent an efficient alternative in the modulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase activity. Indeed it has already been demonstrated that the rise in reactive oxygen species levels causes the complete dephosphorylation and, in turn activation of the enzyme. Many coumarins and their derivatives have the special ability to scavenge reactive oxygen species or show a lipid lowering potential. Here we evaluated whether the coumarin, 4-methylesculetin could exert both the ability to scavenge ROS and to modulate 3-hydroxy-3-methylglutaryl coenzyme A reductase in HepG2 cell line where the enzyme activity dysregulation induced by reactive oxygen species has already been reported. The antioxidant property of 4-methylesculetin led to the reduction of 3-hydroxy-3-methylglutaryl coenzyme A reductase activation state through the increase of the enzyme phosphorylation. In addition, this coumarin showed the ability to modulate 3-hydroxy-3-methylglutaryl coenzyme A reductase protein levels both by transcriptional and degradational events independent of its antioxidant activity.

  14. Coenzyme Engineering of a Hyperthermophilic 6-Phosphogluconate Dehydrogenase from NADP+ to NAD+ with Its Application to Biobatteries

    PubMed Central

    Chen, Hui; Zhu, Zhiguang; Huang, Rui; Zhang, Yi-Heng Percival

    2016-01-01

    Engineering the coenzyme specificity of redox enzymes plays an important role in metabolic engineering, synthetic biology, and biocatalysis, but it has rarely been applied to bioelectrochemistry. Here we develop a rational design strategy to change the coenzyme specificity of 6-phosphogluconate dehydrogenase (6PGDH) from a hyperthermophilic bacterium Thermotoga maritima from its natural coenzyme NADP+ to NAD+. Through amino acid-sequence alignment of NADP+- and NAD+-preferred 6PGDH enzymes and computer-aided substrate-coenzyme docking, the key amino acid residues responsible for binding the phosphate group of NADP+ were identified. Four mutants were obtained via site-directed mutagenesis. The best mutant N32E/R33I/T34I exhibited a ~6.4 × 104-fold reversal of the coenzyme selectivity from NADP+ to NAD+. The maximum power density and current density of the biobattery catalyzed by the mutant were 0.135 mW cm−2 and 0.255 mA cm−2, ~25% higher than those obtained from the wide-type 6PGDH-based biobattery at the room temperature. By using this 6PGDH mutant, the optimal temperature of running the biobattery was as high as 65 °C, leading to a high power density of 1.75 mW cm−2. This study demonstrates coenzyme engineering of a hyperthermophilic 6PGDH and its application to high-temperature biobatteries. PMID:27805055

  15. Coenzyme Engineering of a Hyperthermophilic 6-Phosphogluconate Dehydrogenase from NADP+ to NAD+ with Its Application to Biobatteries

    NASA Astrophysics Data System (ADS)

    Chen, Hui; Zhu, Zhiguang; Huang, Rui; Zhang, Yi-Heng Percival

    2016-11-01

    Engineering the coenzyme specificity of redox enzymes plays an important role in metabolic engineering, synthetic biology, and biocatalysis, but it has rarely been applied to bioelectrochemistry. Here we develop a rational design strategy to change the coenzyme specificity of 6-phosphogluconate dehydrogenase (6PGDH) from a hyperthermophilic bacterium Thermotoga maritima from its natural coenzyme NADP+ to NAD+. Through amino acid-sequence alignment of NADP+- and NAD+-preferred 6PGDH enzymes and computer-aided substrate-coenzyme docking, the key amino acid residues responsible for binding the phosphate group of NADP+ were identified. Four mutants were obtained via site-directed mutagenesis. The best mutant N32E/R33I/T34I exhibited a ~6.4 × 104-fold reversal of the coenzyme selectivity from NADP+ to NAD+. The maximum power density and current density of the biobattery catalyzed by the mutant were 0.135 mW cm‑2 and 0.255 mA cm‑2, ~25% higher than those obtained from the wide-type 6PGDH-based biobattery at the room temperature. By using this 6PGDH mutant, the optimal temperature of running the biobattery was as high as 65 °C, leading to a high power density of 1.75 mW cm‑2. This study demonstrates coenzyme engineering of a hyperthermophilic 6PGDH and its application to high-temperature biobatteries.

  16. Aminoacyl-coenzyme A synthesis catalyzed by a CoA ligase from Penicillium chrysogenum.

    PubMed

    Koetsier, Martijn J; Jekel, Peter A; Wijma, Hein J; Bovenberg, Roel A L; Janssen, Dick B

    2011-03-23

    Coenzyme A ligases play an important role in metabolism by catalyzing the activation of carboxylic acids. In this study we describe the synthesis of aminoacyl-coenzyme As (CoAs) catalyzed by a CoA ligase from Penicillium chrysogenum. The enzyme accepted medium-chain length fatty acids as the best substrates, but the proteinogenic amino acids L-phenylalanine and L-tyrosine, as well as the non-proteinogenic amino acids D-phenylalanine, D-tyrosine and (R)- and (S)-β-phenylalanine were also accepted. Of these amino acids, the highest activity was found for (R)-β-phenylalanine, forming (R)-β-phenylalanyl-CoA. Homology modeling suggested that alanine 312 is part of the active site cavity, and mutagenesis (A312G) yielded a variant that has an enhanced catalytic efficiency with β-phenylalanines and D-α-phenylalanine.

  17. Supplementation with an antioxidant cocktail containing coenzyme Q prevents plasma oxidative damage induced by soccer.

    PubMed

    Tauler, Pedro; Ferrer, Miguel D; Sureda, Antoni; Pujol, Pere; Drobnic, Franchek; Tur, Josep A; Pons, Antoni

    2008-11-01

    The aim of the study was to determine the effects of an antioxidant supplementation, which includes coenzyme Q(10), on plasma and neutrophil oxidative stress and the antioxidant response after a soccer match. Nineteen voluntary male pre-professional footballers were randomly and double-blinded treated with either a multivitamin and mineral supplement (n = 8) or a placebo (n = 11). After the 3 months of supplementation, the sportsmen played a friendly soccer match of 60 min. The 3-month supplementation induced higher plasma ascorbate and coenzyme Q levels when compared to the placebo group. Antioxidant supplementation influenced plasma oxidative stress markers because they were lower in the supplemented group than in the placebo one after the match. The football match induced decreased neutrophil vitamin E levels and catalase and glutathione peroxidase activities but increased glutathione reductase activity. Antioxidant diet supplementation prevented plasma oxidative damage but did not influence the neutrophil response to a football match.

  18. The coenzyme thiamine pyrophosphate inhibits the self-splicing of the group I intron.

    PubMed

    Ahn, Sung Joon; Park, In Kook

    2003-02-01

    Effects of the coenzyme thiamine pyrophosphate and its analogs on the inhibition of self-splicing of primary transcripts of the phage T4 thymidylate synthase gene (td) were investigated. Of all compounds tested, the coenzyme thiamine pyrophosphate was the most potent inhibitor and the order of inhibitory efficiency for compounds tested was as follows: thiamine pyrophosphate>thiamine monophosphate>thiamine>thiochrome. Increasing guanosine concentration overcame the suppression of self-splicing by thiamine pyrophosphate close to the level of normal splicing. Kinetic analysis demonstrated that thiamine pyrophosphate acts as a competitive inhibitor for the td intron RNA with a Ki of 2.2mM. The splicing specificity inhibition by thiamine pyrophosphate is predominantly due to changes in Km.

  19. Reactions of oxygen radicals with the quinone ring of coenzyme Q.

    PubMed

    Fiorentini, D; Cabrini, L; Sechi, A M; Landi, L

    1991-01-01

    Coenzyme Q, besides its role in electron transfer reactions, may act as a radical scavenger. The effect of oxygen radicals produced by ultrasonic irradiation on the quinone ring was investigated. Aqueous solutions of a Q homologue, completely lacking the side chain, were irradiated and the modifications were spectrophotometrically followed. The experimental results show that both degradation and reduction of the benzoquinone ring took place when the irradiation was performed in water. Data obtained when ultrasonic irradiation was carried out in the presence of OH. scavengers, as formate, organic and inorganic buffers, suggest: a) the responsible species for most the ubiquinol generated by sonication appeared to be the superoxide radical b) addition reactions of OH. radicals with the aromatic ring led probably to the degradation of Coenzyme Q molecules.

  20. Primary coenzyme Q10 deficiency presenting as fatal neonatal multiorgan failure.

    PubMed

    Desbats, Maria Andrea; Vetro, Annalisa; Limongelli, Ivan; Lunardi, Giada; Casarin, Alberto; Doimo, Mara; Spinazzi, Marco; Angelini, Corrado; Cenacchi, Giovanna; Burlina, Alberto; Rodriguez Hernandez, Maria Angeles; Chiandetti, Lino; Clementi, Maurizio; Trevisson, Eva; Navas, Placido; Zuffardi, Orsetta; Salviati, Leonardo

    2015-09-01

    Coenzyme Q10 deficiency is a clinically and genetically heterogeneous disorder, with manifestations that may range from fatal neonatal multisystem failure, to adult-onset encephalopathy. We report a patient who presented at birth with severe lactic acidosis, proteinuria, dicarboxylic aciduria, and hepatic insufficiency. She also had dilation of left ventricle on echocardiography. Her neurological condition rapidly worsened and despite aggressive care she died at 23 h of life. Muscle histology displayed lipid accumulation. Electron microscopy showed markedly swollen mitochondria with fragmented cristae. Respiratory-chain enzymatic assays showed a reduction of combined activities of complex I+III and II+III with normal activities of isolated complexes. The defect was confirmed in fibroblasts, where it could be rescued by supplementing the culture medium with 10 μM coenzyme Q10. Coenzyme Q10 levels were reduced (28% of controls) in these cells. We performed exome sequencing and focused the analysis on genes involved in coenzyme Q10 biosynthesis. The patient harbored a homozygous c.545T>G, p.(Met182Arg) alteration in COQ2, which was validated by functional complementation in yeast. In this case the biochemical and morphological features were essential to direct the genetic diagnosis. The parents had another pregnancy after the biochemical diagnosis was established, but before the identification of the genetic defect. Because of the potentially high recurrence risk, and given the importance of early CoQ10 supplementation, we decided to treat with CoQ10 the newborn child pending the results of the biochemical assays. Clinicians should consider a similar management in siblings of patients with CoQ10 deficiency without a genetic diagnosis.

  1. Metal plasmon-coupled fluorescence imaging and label free coenzyme detection in cells

    SciTech Connect

    Zhang, Jian; Fu, Yi; Li, Ge; Zhao, Richard Y.

    2012-08-31

    Highlights: Black-Right-Pointing-Pointer Metal nanoparticle for fluorescence cell imaging. Black-Right-Pointing-Pointer Non-invasive emission detection of coenzyme in cell on time-resolved confocal microscope. Black-Right-Pointing-Pointer Near-field interaction of flavin adenine dinucleotide with silver substrate. Black-Right-Pointing-Pointer Isolation of emissions by coenzymes from cellular autofluorescence on fluorescence cell imaging. -- Abstract: Flavin adenine dinucleotide (FAD) is a key metabolite in cellular energy conversion. Flavin can also bind with some enzymes in the metabolic pathway and the binding sites may be changed due to the disease progression. Thus, there is interest on studying its expression level, distribution, and redox state within the cells. FAD is naturally fluorescent, but it has a modest extinction coefficient and quantum yield. Hence the intrinsic emission from FAD is generally too weak to be isolated distinctly from the cellular backgrounds in fluorescence cell imaging. In this article, the metal nanostructures on the glass coverslips were used as substrates to measure FAD in cells. Particulate silver films were fabricated with an optical resonance near the absorption and the emission wavelengths of FAD which can lead to efficient coupling interactions. As a result, the emission intensity and quantum yield by FAD were greatly increased and the lifetime was dramatically shortened resulting in less interference from the longer lived cellular background. This feature may overcome the technical limits that hinder the direct observation of intrinsically fluorescent coenzymes in the cells by fluorescence microscopy. Fluorescence cell imaging on the metallic particle substrates may provide a non-invasive strategy for collecting the information of coenzymes in cells.

  2. Muscle coenzyme Q10 deficiencies in ataxia with oculomotor apraxia 1.

    PubMed

    Le Ber, I; Dubourg, O; Benoist, J-F; Jardel, C; Mochel, F; Koenig, M; Brice, A; Lombès, A; Dürr, A

    2007-01-23

    APTX gene mutations responsible for ataxia-oculomotor apraxia 1 (AOA1) were identified in a family previously reported with ataxia and coenzyme Q10 (CoQ10) deficiency. We measured muscle CoQ10 levels in six patients with AOA1 and found decreased levels in five. Patients homozygous for the W279X mutation had lower values (p = 0.003). A therapeutic trial of CoQ10 may be warranted in patients with AOA1.

  3. Complete reversal of coenzyme specificity by concerted mutation of three consecutive residues in alcohol dehydrogenase.

    PubMed

    Rosell, Albert; Valencia, Eva; Ochoa, Wendy F; Fita, Ignacio; Parés, Xavier; Farrés, Jaume

    2003-10-17

    Gastric tissues from amphibian Rana perezi express the only vertebrate alcohol dehydrogenase (ADH8) that is specific for NADP(H) instead of NAD(H). In the crystallographic ADH8-NADP+ complex, a binding pocket for the extra phosphate group of coenzyme is formed by ADH8-specific residues Gly223-Thr224-His225, and the highly conserved Leu200 and Lys228. To investigate the minimal structural determinants for coenzyme specificity, several ADH8 mutants involving residues 223 to 225 were engineered and kinetically characterized. Computer-assisted modeling of the docked coenzymes was also performed with the mutant enzymes and compared with the wild-type crystallographic binary complex. The G223D mutant, having a negative charge in the phosphate-binding site, still preferred NADP(H) over NAD(H), as did the T224I and H225N mutants. Catalytic efficiency with NADP(H) dropped dramatically in the double mutants, G223D/T224I and T224I/H225N, and in the triple mutant, G223D/T224I/H225N (kcat/KmNADPH = 760 mm-1 min-1), as compared with the wild-type enzyme (kcat/KmNADPH = 133330 mm-1 min-1). This was associated with a lower binding affinity for NADP+ and a change in the rate-limiting step. Conversely, in the triple mutant, catalytic efficiency with NAD(H) increased, reaching values (kcat/KmNADH = 155000 mm-1 min-1) similar to those of the wild-type enzyme with NADP(H). The complete reversal of ADH8 coenzyme specificity was therefore attained by the substitution of only three consecutive residues in the phosphate-binding site, an unprecedented achievement within the ADH family.

  4. Modular coenzyme specificity: a domain-swopped chimera of glutamate dehydrogenase.

    PubMed

    Sharkey, Michael A; Engel, Paul C

    2009-11-01

    Domain-swopped chimeras of the glutamate dehydrogenases from Clostridium symbiosum (CsGDH) (NAD(+)-specific) and Escherichia coli (EcGDH) (NADP(+)-specific) have been produced, with the aim of testing the localization of determinants of coenzyme specificity. An active chimera consisting of the substrate-binding domain (Domain I) of CsGDH and the coenzyme-binding domain (Domain II) of EcGDH has been purified to homogeneity, and a thorough kinetic analysis has been carried out. Results indicate that selectivity for the phosphorylated coenzyme does indeed reside solely in Domain II; the chimera utilizes NAD(+) at 0.8% of the rate observed with NADP(+), similar to the 0.5% ratio for EcGDH. Positive cooperativity toward L-glutamate, characteristic of CsGDH, has been retained with Domain I. An unforeseen feature of this chimera, however, is that, although glutamate cooperativity occurs only at higher pH values in the parent CsGDH, the chimeric protein shows it over the full pH range explored. Also surprising is that the chimera is capable of catalysing severalfold higher reaction rates (V(max)) in both directions than either of the parent enzymes from which it is constructed.

  5. An investigation of possible competing mechanisms for Ni-containing methyl-coenzyme M reductase.

    PubMed

    Chen, Shi-Lu; Blomberg, Margareta R A; Siegbahn, Per E M

    2014-07-21

    Ni-containing methyl-coenzyme M reductase (MCR) is capable of catalyzing methane formation from methyl-coenzyme M (CH3-SCoM) and coenzyme B (CoB-SH), and also its reverse reaction (methane oxidation). Based on extensive experimental and theoretical investigations, it has turned out that a mechanism including an organometallic methyl-Ni(III)F430 intermediate is inaccessible, while another mechanism involving a methyl radical and a Ni(II)-SCoM species currently appears to be the most acceptable one for MCR. In the present paper, using hybrid density functional theory and an active-site model based on the X-ray crystal structure, two other mechanisms were studied and finally also ruled out. One of them, involving proton binding on the CH3-SCoM substrate, which should facilitate methyl-Ni(III)F430 formation, is demonstrated to be quite unfavorable since the substrate has a much smaller proton affinity than the F430 cofactor. Another one (oxidative addition mechanism) is also shown to be unfavorable for the MCR reaction, due to the large endothermicity for the formation of the ternary intermediate with side-on C-S (for CH3-SCoM) or C-H (for methane) coordination to Ni.

  6. Structure of a methyl-coenzyme M reductase from Black Sea mats that oxidize methane anaerobically.

    PubMed

    Shima, Seigo; Krueger, Martin; Weinert, Tobias; Demmer, Ulrike; Kahnt, Jörg; Thauer, Rudolf K; Ermler, Ulrich

    2011-11-27

    The anaerobic oxidation of methane (AOM) with sulphate, an area currently generating great interest in microbiology, is accomplished by consortia of methanotrophic archaea (ANME) and sulphate-reducing bacteria. The enzyme activating methane in methanotrophic archaea has tentatively been identified as a homologue of methyl-coenzyme M reductase (MCR) that catalyses the methane-forming step in methanogenic archaea. Here we report an X-ray structure of the 280 kDa heterohexameric ANME-1 MCR complex. It was crystallized uniquely from a protein ensemble purified from consortia of microorganisms collected with a submersible from a Black Sea mat catalysing AOM with sulphate. Crystals grown from the heterogeneous sample diffract to 2.1 Å resolution and consist of a single ANME-1 MCR population, demonstrating the strong selective power of crystallization. The structure revealed ANME-1 MCR in complex with coenzyme M and coenzyme B, indicating the same substrates for MCR from methanotrophic and methanogenic archaea. Differences between the highly similar structures of ANME-1 MCR and methanogenic MCR include a F(430) modification, a cysteine-rich patch and an altered post-translational amino acid modification pattern, which may tune the enzymes for their functions in different biological contexts.

  7. An in vitro evolved glmS ribozyme has the wildtype fold but loses coenzyme dependence

    PubMed Central

    Lau, Matthew W. L.; Ferré-D’Amaré, Adrian R.

    2014-01-01

    Uniquely among known ribozymes, the glmS ribozyme-riboswitch requires a small-molecule coenzyme, glucosamine-6-phosphate (GlcN6P). Although consistent with its gene-regulatory function, use of GlcN6P is unexpected because all other characterized self-cleaving ribozymes employ RNA functional groups or divalent cations for catalysis. To determine what active site features make this ribozyme reliant on GlcN6P, and to evaluate whether it might have evolved from a coenzyme-independent ancestor, we isolated a GlcN6P-independent variant through in vitro selection. Three active site mutations suffice to generate a highly reactive RNA that adopts the wildtype fold but employs divalent cations for catalysis and is insensitive to GlcN6P. Biochemical and crystallographic comparisons of wildtype and mutant ribozymes show that a handful of functional groups fine-tune the RNA to be either coenzyme- or cation-dependent. These results indicate that a few mutations can confer novel biochemical activities on structured RNAs. Thus, families of structurally related ribozymes with divergent function may exist. PMID:24096303

  8. Coenzyme Q{sub 10} and alpha-tocopherol protect against amitriptyline toxicity

    SciTech Connect

    Cordero, Mario D.; Moreno-Fernandez, Ana Maria; Gomez-Skarmeta, Jose Luis; Miguel, Manuel de; Garrido-Maraver, Juan; Oropesa-Avila, Manuel; Rodriguez-Hernandez, Angeles; Navas, Placido; Sanchez-Alcazar, Jose Antonio

    2009-03-15

    Since amitriptyline is a very frequently prescribed antidepressant drug, it is not surprising that amitriptyline toxicity is relatively common. Amitriptyline toxic systemic effects include cardiovascular, autonomous nervous, and central nervous systems. To understand the mechanisms of amitriptyline toxicity we studied the cytotoxic effects of amitriptyline treatment on cultured primary human fibroblasts and zebrafish embryos, and the protective role of coenzyme Q{sub 10} and alpha-tocopherol, two membrane antioxidants. We found that amitriptyline treatment induced oxidative stress and mitochondrial dysfunction in primary human fibroblasts. Mitochondrial dysfunction in amitriptyline treatment was characterized by reduced expression levels of mitochondrial proteins and coenzyme Q{sub 10}, decreased NADH:cytochrome c reductase activity, and a drop in mitochondrial membrane potential. Moreover, and as a consequence of these toxic effects, amitriptyline treatment induced a significant increase in apoptotic cell death activating mitochondrial permeability transition. Coenzyme Q{sub 10} and alpha-tocopherol supplementation attenuated ROS production, lipid peroxidation, mitochondrial dysfunction, and cell death, suggesting that oxidative stress affecting cell membrane components is involved in amitriptyline cytotoxicity. Furthermore, amitriptyline-dependent toxicity and antioxidant protection were also evaluated in zebrafish embryos, a well established vertebrate model to study developmental toxicity. Amitriptyline significantly increased embryonic cell death and apoptosis rate, and both antioxidants provided a significant protection against amitriptyline embryotoxicity.

  9. ACX3, a Novel Medium-Chain Acyl-Coenzyme A Oxidase from Arabidopsis

    PubMed Central

    Froman, Byron E.; Edwards, Patricia C.; Bursch, Adam G.; Dehesh, Katayoon

    2000-01-01

    In a database search for homologs of acyl-coenzyme A oxidases (ACX) in Arabidopsis, we identified a partial genomic sequence encoding an apparently novel member of this gene family. Using this sequence information we then isolated the corresponding full-length cDNA from etiolated Arabidopsis cotyledons and have characterized the encoded recombinant protein. The polypeptide contains 675 amino acids. The 34 residues at the amino terminus have sequence similarity to the peroxisomal targeting signal 2 of glyoxysomal proteins, including the R-[I/Q/L]-X5-HL-XL-X15-22-C consensus sequence, suggesting a possible microsomal localization. Affinity purification of the encoded recombinant protein expressed in Escherichia coli followed by enzymatic assay, showed that this enzyme is active on C8:0- to C14:0-coenzyme A with maximal activity on C12:0-coenzyme A, indicating that it has medium-chain-specific activity. These data indicate that the protein reported here is different from previously characterized classes of ACX1, ACX2, and short-chain ACX (SACX), both in sequence and substrate chain-length specificity profile. We therefore, designate this new gene AtACX3. The temporal and spatial expression patterns of AtACX3 during development and in various tissues were similar to those of the AtSACX and other genes expressed in glyoxysomes. Currently available database information indicates that AtACX3 is present as a single copy gene. PMID:10859203

  10. Mutations that affect coenzyme binding and dimer formation of fungal 17beta-hydroxysteroid dehydrogenase.

    PubMed

    Brunskole, Mojca; Kristan, Katja; Stojan, Jure; Rizner, Tea Lanisnik

    2009-03-25

    The 17beta-hydroxysteroid dehydrogenase from the fungus Cochliobolus lunatus (17beta-HSDcl) is an NADPH-dependent member of the short-chain dehydrogenase/reductase superfamily, and it functions as a dimer that is composed of two identical subunits. By constructing the appropriate mutants, we have examined the M204 residue that is situated in the coenzyme binding pocket, for its role in the binding of the coenzyme NADP(H). We have also studied the importance of hydrophobic interactions through F124, F132, F133 and F177 for 17beta-HSDcl dimer formation. The M204G substitution decreased the catalytic efficiency of 17beta-HSDcl, suggesting that M204 sterically coerces the nicotinamide moiety of the coenzyme into the appropriate position for further hydride transfer. Phenylalanine substitutions introduced at the dimer interface produced inactive aggregates and oligomers with high molecular masses, suggesting that these hydrophobic interactions have important roles in the formation of the active dimer.

  11. Coenzyme Q10 Supplementation Modulates NFκB and Nrf2 Pathways in Exercise Training.

    PubMed

    Pala, Ragip; Orhan, Cemal; Tuzcu, Mehmet; Sahin, Nurhan; Ali, Shakir; Cinar, Vedat; Atalay, Mustafa; Sahin, Kazim

    2016-03-01

    This study reports the effects of Q10, coenzyme Q10 or ubiquinone, a component of the electron transport chain in mitochondria, on nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), inhibitors of kappa B (IκB), nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and hemeoxygenase 1 (HO-1) in rats after chronic exercise training for 6 weeks. 8-week old male Wistar rats were assigned randomly to one of four treatments planned in a 2 x 2 factorial arrangement of two condition (sedentary vs. exercise training), and two coenzyme Q10 levels (0 and 300 mg/kg per day for 6 weeks). The expression levels of the target proteins were determined in the heart, liver and muscle, and biochemical parameters including creatinine, urea, glucose and lipid profile were investigated in plasma. When compared with sedentary group, significant decreases in heart, liver and muscle NFκB levels by 45%, 26% and 44% were observed in Q10 supplemented rats after exercise training, respectively, while the inhibitory protein IκB increased by 179%, 111% and 127% in heart, liver and muscle tissues. Q10 supplementation caused an increase in Nrf2 (167%, 165% and 90%) and HO-1 (107%, 156% and 114%) after exercise training in heart, liver and muscle tissues (p < 0.05). No significant change was observed in any of the parameters associated with protein, carbohydrate and lipid metabolism, except that exercise caused a decrease in plasma triglyceride, which was further decreased by Q10. In conclusion, these results suggest that Q10 modulates the expression of NFκB, IκB, Nrf2 and HO-1 in exercise training, indicating an anti-inflammatory effect of Q10 and emphasizes its role in antioxidant defense. Key pointsCoenzyme Q10 is a component of the electron transport chain in mitochondria which is linked to the generation of energy in the cell.Coenzyme Q10 may inhibit the peroxidation of lipids, thus acting as an antioxidant and protects tissue against oxidative injury.Using of coenzyme Q

  12. Coenzyme Q10 Supplementation Modulates NFκB and Nrf2 Pathways in Exercise Training

    PubMed Central

    Pala, Ragip; Orhan, Cemal; Tuzcu, Mehmet; Sahin, Nurhan; Ali, Shakir; Cinar, Vedat; Atalay, Mustafa; Sahin, Kazim

    2016-01-01

    This study reports the effects of Q10, coenzyme Q10 or ubiquinone, a component of the electron transport chain in mitochondria, on nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), inhibitors of kappa B (IκB), nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and hemeoxygenase 1 (HO-1) in rats after chronic exercise training for 6 weeks. 8-week old male Wistar rats were assigned randomly to one of four treatments planned in a 2 x 2 factorial arrangement of two condition (sedentary vs. exercise training), and two coenzyme Q10 levels (0 and 300 mg/kg per day for 6 weeks). The expression levels of the target proteins were determined in the heart, liver and muscle, and biochemical parameters including creatinine, urea, glucose and lipid profile were investigated in plasma. When compared with sedentary group, significant decreases in heart, liver and muscle NFκB levels by 45%, 26% and 44% were observed in Q10 supplemented rats after exercise training, respectively, while the inhibitory protein IκB increased by 179%, 111% and 127% in heart, liver and muscle tissues. Q10 supplementation caused an increase in Nrf2 (167%, 165% and 90%) and HO-1 (107%, 156% and 114%) after exercise training in heart, liver and muscle tissues (p < 0.05). No significant change was observed in any of the parameters associated with protein, carbohydrate and lipid metabolism, except that exercise caused a decrease in plasma triglyceride, which was further decreased by Q10. In conclusion, these results suggest that Q10 modulates the expression of NFκB, IκB, Nrf2 and HO-1 in exercise training, indicating an anti-inflammatory effect of Q10 and emphasizes its role in antioxidant defense. Key points Coenzyme Q10 is a component of the electron transport chain in mitochondria which is linked to the generation of energy in the cell. Coenzyme Q10 may inhibit the peroxidation of lipids, thus acting as an antioxidant and protects tissue against oxidative injury. Using of coenzyme

  13. The PduL Phosphotransacylase Is Used To Recycle Coenzyme A within the Pdu Microcompartment

    PubMed Central

    Liu, Yu; Jorda, Julien; Yeates, Todd O.

    2015-01-01

    ABSTRACT In Salmonella enterica, 1,2-propanediol (1,2-PD) utilization (Pdu) is mediated by a bacterial microcompartment (MCP). The Pdu MCP consists of a multiprotein shell that encapsulates enzymes and cofactors for 1,2-PD catabolism, and its role is to sequester a reactive intermediate (propionaldehyde) to minimize cellular toxicity and DNA damage. For the Pdu MCP to function, the enzymes encapsulated within must be provided with a steady supply of substrates and cofactors. In the present study, Western blotting assays were used to demonstrate that the PduL phosphotransacylase is a component of the Pdu MCP. We also show that the N-terminal 20-residue-long peptide of PduL is necessary and sufficient for targeting PduL and enhanced green fluorescent protein (eGFP) to the lumen of the Pdu MCP. We present the results of genetic tests that indicate that PduL plays a role in the recycling of coenzyme A internally within the Pdu MCP. However, the results indicate that some coenzyme A recycling occurs externally to the Pdu MCP. Hence, our results support a model in which a steady supply of coenzyme A is provided to MCP lumen enzymes by internal recycling by PduL as well as by the movement of coenzyme A across the shell by an unknown mechanism. These studies expand our understanding of the Pdu MCP, which has been linked to enteric pathogenesis and which provides a possible basis for the development of intracellular bioreactors for use in biotechnology. IMPORTANCE Bacterial MCPs are widespread organelles that play important roles in pathogenesis and global carbon fixation. Here we show that the PduL phosphotransacylase is a component of the Pdu MCP. We also show that PduL plays a key role in cofactor homeostasis by recycling coenzyme A internally within the Pdu MCP. Further, we identify a potential N-terminal targeting sequence using a bioinformatic approach and show that this short sequence extension is necessary and sufficient for directing PduL as well as heterologous

  14. Whole Blood Metabolomics by (1)H NMR Spectroscopy Provides a New Opportunity To Evaluate Coenzymes and Antioxidants.

    PubMed

    Nagana Gowda, G A; Raftery, Daniel

    2017-03-30

    Conventional human blood metabolomics employs serum or plasma and provides a wealth of metabolic information therein. However, this approach lacks the ability to measure and evaluate important metabolites such as coenzymes and antioxidants that are present at high concentrations in red blood cells. As an important alternative to serum/plasma metabolomics, we show here that a simple (1)H NMR experiment can simultaneously measure coenzymes and antioxidants in extracts of whole human blood, in addition to the nearly 70 metabolites that were shown to be quantitated in serum/plasma recently [ Anal. Chem. 2015 , 87 , 706 - 715 ]. Coenzymes of redox reactions: oxidized/reduced nicotinamide adenine dinucleotide (NAD(+) and NADH) and nicotinamide adenine dinucleotide phosphate (NADP(+) and NADPH); coenzymes of energy including adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP); and antioxidants, the sum of oxidized and reduced glutathione (GSSG and GSH) can be measured with essentially no additional effort. A new method was developed for detecting many of these unstable species without affecting other blood/blood plasma metabolites. The identities of coenzymes and antioxidants in blood NMR spectra were established combining 1D/2D NMR techniques, chemical shift databases, pH measurements and, finally, spiking with authentic compounds. This is the first study to report identification of major coenzymes and antioxidants and quantify them, simultaneously, with the large pool of other metabolites in human blood using NMR spectroscopy. Considering that the levels of coenzymes and antioxidants represent a sensitive measure of cellular functions in health and numerous diseases, the NMR method presented here potentially opens a new chapter in the metabolomics of blood.

  15. The mechanism of discrimination between oxidized and reduced coenzyme in the aldehyde dehydrogenase domain of Aldh1l1.

    PubMed

    Tsybovsky, Yaroslav; Malakhau, Yuryi; Strickland, Kyle C; Krupenko, Sergey A

    2013-02-25

    Aldh1l1, also known as 10-formyltetrahydrofolate dehydrogenase (FDH), contains the carboxy-terminal domain (Ct-FDH), which is a structural and functional homolog of aldehyde dehydrogenases (ALDHs). This domain is capable of catalyzing the NADP(+)-dependent oxidation of short chain aldehydes to their corresponding acids, and similar to most ALDHs it has two conserved catalytic residues, Cys707 and Glu673. Previously, we demonstrated that in the Ct-FDH mechanism these residues define the conformation of the bound coenzyme and the affinity of its interaction with the protein. Specifically, the replacement of Cys707 with an alanine resulted in the enzyme lacking the ability to differentiate between the oxidized and reduced coenzyme. We suggested that this was due to the loss of a covalent bond between the cysteine and the C4N atom of nicotinamide ring of NADP(+) formed during Ct-FDH catalysis. To obtain further insight into the functional significance of the covalent bond between Cys707 and the coenzyme, and the overall role of the two catalytic residues in the coenzyme binding and positioning, we have now solved crystal structures of Ct-FDH in the complex with thio-NADP(+) and the complexes of the C707S mutant with NADP(+) and NADPH. This study has allowed us to trap the coenzyme in the contracted conformation, which provided a snapshot of the conformational processing of the coenzyme during the transition from oxidized to reduced form. Overall, the results of this study further support the previously proposed mechanism by which Cys707 helps to differentiate between the oxidized and reduced coenzyme during ALDH catalysis.

  16. Thermodynamics of various F420 coenzyme models as sources of electrons, hydride ions, hydrogen atoms and protons in acetonitrile.

    PubMed

    Xia, Ke; Shen, Guang-Bin; Zhu, Xiao-Qing

    2015-06-14

    32 F420 coenzyme models with alkylation of the three different N atoms (N1, N3 and N10) in the core structure (XFH(-)) were designed and synthesized and the thermodynamic driving forces (defined in terms of the molar enthalpy changes or the standard redox potentials in this work) of the 32 XFH(-) releasing hydride ions, hydrogen atoms and electrons, the thermodynamic driving forces of the 32 XFH˙ releasing protons and hydrogen atoms and the thermodynamic driving forces of XF(-)˙ releasing electrons in acetonitrile were determined using titration calorimetry and electrochemical methods. The effects of the methyl group at N1, N3 and N10 and a negative charge on N1 and N10 atoms on the six thermodynamic driving forces of the F420 coenzyme models and their related reaction intermediates were examined; the results show that seating arrangements of the methyl group and the negative charge have remarkably different effects on the thermodynamic properties of the F420 coenzyme models and their related reaction intermediates. The effects of the substituents at C7 and C8 on the six thermodynamic driving forces of the F420 coenzyme models and their related reaction intermediates were also examined; the results show that the substituents at C7 and C8 have good Hammett linear free energy relationships with the six thermodynamic parameters. Meanwhile, a reasonable determination of possible reactions between members of the F420 family and NADH family in vivo was given according to a thermodynamic analysis platform constructed using the elementary step thermodynamic parameter of F420 coenzyme model 2FH(-) and NADH model MNAH releasing hydride ions in acetonitrile. The information disclosed in this work can not only fill a gap in the chemical thermodynamics of F420 coenzyme models as a class of very important organic sources of electrons, hydride ions, hydrogen atoms and protons, but also strongly promote the fast development of the chemistry and applications of F420 coenzyme.

  17. Spectroscopic and computational studies of reduction of the metalversus the tetrapyrrole ring of coenzyme F-430 from methyl-coenzyme Mreductase

    SciTech Connect

    Dey, Mishtu; Kunz, Ryan C.; van Heuvelen, Katherine M.; Craft,Jennifer L.; Horng, Yih-Chern; Tang, Qun; Bocian, David F.; George, SimonJ.; Brunold, Thomas C.; Ragsdale, Stephen W.

    2006-06-30

    Methyl-coenzyme M reductase (MCR) catalyzes the final stepin methane biosynthesis by methanogenic archaea and contains aredox-active nickel tetrahydrocorphin, coenzyme F430, at its active site.Spectroscopic and computational methods have been used to study a novelform of the coenzyme, called F330, which is obtained by reducing F430with sodium borohydride (NaBH4). F330 exhibits a prominent absorptionpeak at 330 nm, which is blue shifted by 100 nm relative to F430. Massspectrometric studies demonstrate that the tetrapyrrole ring in F330 hasundergone reduction, on the basis of the incorporation of protium (ordeuterium), upon treatment of F430 with NaBH4 (or NaBD4). One- andtwo-dimensional NMR studies show that the site of reduction is theexocyclic ketone group of the tetrahydrocorphin. Resonance Raman studiesindicate that elimination of this pibond increases the overall pi-bondorder in the conjugative framework. X-ray absorption, magnetic circulardichroism, and computational results show that F330 contains low-spinNi(II). Thus, conversion of F430 to F330 reduces the hydrocorphin ringbut not the metal. Conversely, reduction of F430 with Ti(III) citrate togenerate F380 (corresponding to the active MCRred1 state) reduces theNi(II) to Ni(I) but does not reduce the tetrapyrrole ring system, whichis consistent with other studies [Piskorski, R., and Jaun, B. (2003) J.Am. Chem. Soc. 125, 13120-13125; Craft, J. L., et al. (2004) J. Biol.Inorg. Chem. 9, 77-89]. The distinct origins of the absorption bandshifts associated with the formation of F330 and F380 are discussedwithin the framework of our computational results. These studies on thenature of the product(s) of reduction of F430 are of interest in thecontext of the mechanism of methane formation by MCR and in relation tothe chemistry of hydroporphinoid systems in general. The spectroscopicand time-dependent DFT calculations add important insight into theelectronic structure of the nickel hydrocorphinate in its Ni(II) and

  18. Solution structure, enzymatic, and non-enzymatic reactivity of 3-isoadenosylcobalamin, a structural isomer of coenzyme B12 with surprising coenzymic activity.

    PubMed

    Brown, Kenneth L; Zou, Xiang; Chen, Guodong; Xia, Zuping; Marques, Helder M

    2004-02-01

    The coenzymic activity of eight analogs of coenzyme B(12) (5'-deoxyadenosyl-cobalamin, AdoCbl) with structural alterations in the Ado ligand has been investigated with the AdoCbl-dependent ribonucleoside triphosphate reductase (RTPR) from Lactobacillus leichmannii. Six of the analogs were partially active coenzymes, and one, 3-iso-5'-deoxyadenosylcobalamin (3-IsoAdoCbl) was nearly as active as AdoCbl itself. NMR-restrained molecular modeling of 3-IsoAdoCbl revealed a highly conformationally mobile structure which required a four state model to be consistent with the NMR data. Thus, two conformations, one with the IsoAdo ligand over the eastern quadrant of the corrin, and one with the IsoAdo ligand over the northern quadrant, each undergo a facile syn/anti conformational equilibrium in the IsoAdo ligand. Spectrophotometric measurement of the kinetics of RTPR-induced cleavage of the carbon-cobalt bond of 3-IsoAdoCbl showed that it binds to the enzyme with the same affinity as AdoCbl, but its homolysis is only 20% as rapid. Investigation of the non-enzymatic thermolysis of 3-IsoAdoCbl showed that like AdoCbl, 3-IsoAdoCbl decomposes by competing homolytic and heterolytic pathways. A complete temperature-dependent kinetic and product analysis, followed by correction for the base-off species permitted deconvolution of the specific rate constant for both pathways. Eyring plots for the homolysis and heterolysis rate constant cross at 93 degrees C, so that homolysis is the predominant pathway at high temperature, but heterolysis is the predominant pathway at low temperature. At 37 degrees C, the homolysis of 3-IsoAdoCbl is 5.5-fold faster than that of AdoCbl, and the enzyme catalyzes carbon-cobalt bond homolysis in 3-IsoAdoCbl by a factor of 5.9 x 10(7), only 3.9% of the catalytic efficiency with AdoCbl itself. It seems likely that the conformational flexibility of 3-IsoAdoCbl allows it to adopt a coformation in which the hydrogen bonding patterns of the adenine moiety are

  19. Effects of L-carnitine and coenzyme q10 on impaired spermatogenesis caused by isoproterenol in male rats.

    PubMed

    Ghanbarzadeh, S; Garjani, A; Ziaee, M; Khorrami, A

    2014-09-01

    Nowadays, cardiovascular diseases and male infertility are two big health problems in industrial countries.The aim of the present study was to investigate the protective role of coenzyme Q10 and L-Carnitine pretreatment in the impaired spermatogenesis caused by isoproterenol (ISO) in male rats.Thirty-two male Wistar rats were allocated in 4 groups. ISO was injected for 2 consecutive days (100 mg/kg) in ISO treated groups. Before ISO administration, pretreatment with Coenzyme Q10 (10 mg/kg/day) and L-Carnitine (350 mg/kg/day) were conducted for 20 consecutive days. Sex hormones level, malondialdehyde (MDA) and total antioxidant concentration as well as testis, epididymis and seminal vesicle weight were investigated.Increase in the concentration of MDA and decrease in total antioxidant level was observed following ISO administration. Accordingly, the sperm viability as well as testis, epididymis and seminal vesicle weights were decreased. In the case of sex hormones, the testosterone and LH levels were decreased and the concentration of FSH was increased. Pretreatment with L-carnitine and Coenzyme Q10 significantly decreased the MDA level and increased total antioxidant, LH and testosterone levels. Pretreatment with L-carnitine and Coenzyme Q10 also improved semen parameters and organs weight which were impaired by ISO administration.L-carnitine and Coenzyme Q10 pretreatment could protect spermatogenesis in male rats with ISO administration.

  20. Effect of concomitant administration of coenzyme Q10 with sitagliptin on experimentally induced diabetic nephropathy in rats.

    PubMed

    Maheshwari, Rajesh; Balaraman, Ramachandran; Sen, Ashim Kumar; Shukla, Disha; Seth, Avinash

    2017-11-01

    This study was aimed to investigate the therapeutic potential of coenzyme Q10 and its combination with sitagliptin in experimentally induced diabetic nephropathy. The diabetic rats were treated with coenzyme Q10 or sitagliptin and their concomitant administration. Various parameters of renal function like serum creatinine, urea, uric acid and markers of oxidative stress such as renal malondialdehyde content (MDA), glutathione (GSH) level and superoxide dismutase (SOD), catalase activities were measured. TNF-α, TGF-β, MPO activity and nitrite content were estimated in renal tissue with histopathological observation. Diabetic rats showed a significant reduction in renal function, which was reflected with an increase in serum creatinine, urea and uric acid levels. Streptozotocin-nicotinamide caused renal tubular damage with a higher MDA level, depletion of SOD and CAT activity and GSH level. In addition, TNF-α, TGF- β, MPO activity and nitrite content were significantly increased in diabetic rats. Treatment with coenzyme Q10 or sitagliptin and their co-administration ameliorated STZ-nicotinamide-induced renal damage which was reflected by decreased oxidative stress, TNF-α, TGF-β, MPO activity, nitrite content along with histopathological changes. To conclude, concomitant administration of coenzyme Q10 and sitagliptin showed a better renoprotective effect than coenzyme Q10 or sitagliptin when given alone.

  1. Synthesis, solution and crystal structure of the coenzyme B(12) analogue Co(β)-2'-fluoro-2',5'-dideoxyadenosylcobalamin.

    PubMed

    Hunger, Miriam; Wurst, Klaus; Kräutler, Bernhard

    2015-07-01

    Crystal structure analyses have helped to decipher the mode of binding of coenzyme B12 (AdoCbl) in the active site of AdoCbl-dependent enzymes. However, the question of how such enzymes perform their radical reactions is still incompletely answered. A pioneering study by Gruber and Kratky of AdoCbl-dependent glutamate mutase (GLM) laid out a path for the movement of the catalytically active 5'-deoxyadenosyl radical, in which H-bonds between the protein and the 2'- and 3'-OH groups of the protein bound AdoCbl would play a decisive role. Studies with correspondingly modified coenzyme B12-analogues are of interest to gain insights into cofactor binding and enzyme mechanism. Here we report the preparation of Coβ-2'-fluoro-2',5'-dideoxyadenosylcobalamin (2'FAdoCbl), which lacks the 2'-OH group critical for the interaction in enzymes. 2'FAdoCbl was prepared by alkylation of cob(I)alamin, obtained from the electrochemical reduction of aquocobalamin. Spectroscopic data and a single crystal X-ray analysis of 2'FAdoCbl established its structure, which was very similar to that one of coenzyme B12. 2'FAdoCbl is a (19)F NMR active mimic of coenzyme B12 that may help to gain insights into binding interactions of coenzyme B12 with AdoCbl-dependent enzymes, proteins of B12 transport and of AdoCbl-biosynthesis, as well as with B12-riboswitches.

  2. The use of coenzyme Q0 as a template in the development of a molecularly imprinted polymer for the selective recognition of coenzyme Q10.

    PubMed

    Contin, Mario; Flor, Sabrina; Martinefski, Manuela; Lucangioli, Silvia; Tripodi, Valeria

    2014-01-07

    In this work, a novel molecularly imprinted polymer (MIP) for use as a solid phase extraction sorbent was developed for the determination of coenzyme Q10 (CoQ10) in liver extract. CoQ10 is an essential cofactor in mitochondrial oxidative phosphorylation and a powerful antioxidant agent found in low concentrations in biological samples. This fact and its high hydrophobicity make the analysis of CoQ10 technically challenging. Accordingly, a MIP was synthesised using coenzyme Q0 as the template, methacrylic acid as the functional monomer, acetonitrile as the porogen, ethylene glycol dimethacrylate as the crosslinker and benzoyl peroxide as the initiator. Various parameters affecting the polymer preparation and extraction efficiency were evaluated. Morphological characterisation of the MIP and its proper comparison with C18 as a sorbent in solid phase extraction were performed. The optimal conditions for the molecularly imprinted solid phase extraction (MISPE) consisted of 400 μL of sample mixed with 30 mg of MIP and 600 μL of water to reach the optimum solution loading. The loading was followed by a washing step consisting of 1 mL of a 1-propanol solution (1-propanol:water, 30:70,v/v) and elution with 1 mL of 1-propanol. After clean-up, the CoQ10 in the samples was analysed by high performance liquid chromatography. The extraction recoveries were higher than 73.7% with good precision (3.6-8.3%). The limits of detection and quantification were 2.4 and 7.5 μg g(-1), respectively, and a linear range between 7.5 and 150 μg g(-1) of tissue was achieved. The new MISPE procedure provided a successful clean-up for the determination of CoQ10 in a complex matrix.

  3. Properties of Succinyl-Coenzyme A:l-Malate Coenzyme A Transferase and Its Role in the Autotrophic 3-Hydroxypropionate Cycle of Chloroflexus aurantiacus

    PubMed Central

    Friedmann, Silke; Steindorf, Astrid; Alber, Birgit E.; Fuchs, Georg

    2006-01-01

    The 3-hydroxypropionate cycle has been proposed to operate as the autotrophic CO2 fixation pathway in the phototrophic bacterium Chloroflexus aurantiacus. In this pathway, acetyl coenzyme A (acetyl-CoA) and two bicarbonate molecules are converted to malate. Acetyl-CoA is regenerated from malyl-CoA by l-malyl-CoA lyase. The enzyme forming malyl-CoA, succinyl-CoA:l-malate coenzyme A transferase, was purified. Based on the N-terminal amino acid sequence of its two subunits, the corresponding genes were identified on a gene cluster which also contains the gene for l-malyl-CoA lyase, the subsequent enzyme in the pathway. Both enzymes were severalfold up-regulated under autotrophic conditions, which is in line with their proposed function in CO2 fixation. The two CoA transferase genes were cloned and heterologously expressed in Escherichia coli, and the recombinant enzyme was purified and studied. Succinyl-CoA:l-malate CoA transferase forms a large (αβ)n complex consisting of 46- and 44-kDa subunits and catalyzes the reversible reaction succinyl-CoA + l-malate → succinate + l-malyl-CoA. It is specific for succinyl-CoA as the CoA donor but accepts l-citramalate instead of l-malate as the CoA acceptor; the corresponding d-stereoisomers are not accepted. The enzyme is a member of the class III of the CoA transferase family. The demonstration of the missing CoA transferase closes the last gap in the proposed 3-hydroxypropionate cycle. PMID:16547052

  4. Sensitive non-radioactive determination of aminotransferase stereospecificity for C-4' hydrogen transfer on the coenzyme

    SciTech Connect

    Jomrit, Juntratip; Summpunn, Pijug; Meevootisom, Vithaya; Wiyakrutta, Suthep

    2011-02-25

    Research highlights: {yields} Stereochemical mechanism of PLP enzymes is important but difficult to determine. {yields} This new method is significantly less complicated than the previous ones. {yields} This assay is as sensitive as the radioactive based method. {yields} LC-MS/MS positively identify the analyte coenzyme. {yields} The method can be used with enzyme whose apo form is unstable. -- Abstract: A sensitive non-radioactive method for determination of the stereospecificity of the C-4' hydrogen transfer on the coenzymes (pyridoxal phosphate, PLP; and pyridoxamine phosphate, PMP) of aminotransferases has been developed. Aminotransferase of unknown stereospecificity in its PLP form was incubated in {sup 2}H{sub 2}O with a substrate amino acid resulted in PMP labeled with deuterium at C-4' in the pro-S or pro-R configuration according to the stereospecificity of the aminotransferase tested. The [4'-{sup 2}H]PMP was isolated from the enzyme protein and divided into two portions. The first portion was incubated in aqueous buffer with apo-aspartate aminotransferase (a reference si-face specific enzyme), and the other was incubated with apo-branched-chain amino acid aminotransferase (a reference re-face specific enzyme) in the presence of a substrate 2-oxo acid. The {sup 2}H at C-4' is retained with the PLP if the aminotransferase in question transfers C-4' hydrogen on the opposite face of the coenzyme compared with the reference aminotransferase, but the {sup 2}H is removed if the test and reference aminotransferases catalyze hydrogen transfer on the same face. PLP formed in the final reactions was analyzed by LC-MS/MS for the presence or absence of {sup 2}H. The method was highly sensitive that for the aminotransferase with ca. 50 kDa subunit molecular weight, only 2 mg of the enzyme was sufficient for the whole test. With this method, the use of radioactive substances could be avoided without compromising the sensitivity of the assay.

  5. Catalysis by methyl-coenzyme M reductase: a theoretical study for heterodisulfide product formation.

    PubMed

    Pelmenschikov, Vladimir; Siegbahn, Per E M

    2003-07-01

    Hybrid density functional theory has been used to investigate the catalytic mechanism of methyl-coenzyme M reductase (MCR), an essential enzyme in methanogenesis. In a previous study of methane formation, a scheme was suggested involving oxidation of Ni(I) in the starting square-planar coordination to the high-spin Ni(II) form in the CoM-S-Ni(II)F(430) octahedral intermediate. The methyl radical, concomitantly released by methyl-coenzyme M (CoM), is rapidly quenched by hydrogen atom transfer from the coenzyme B (CoB) thiol group, yielding methane as the first product of the reaction. The present investigation primarily concerns the second and final step of the reaction: oxidation of CoB and CoM to the CoB-S-S-CoM heterodisulfide product and reduction of nickel back to the Ni(I) square-planar form. The activation energy for the second step is found to be around 10 kcal/mol, implying that the first step of methane formation with an activation energy of 20 kcal/mol should be rate-limiting. An oxygen of the Gln147 residue, occupying the rear axial position in the oxidized Ni(II) state, is shown to stabilize the intermediate by 6 kcal/mol, thereby slightly decreasing the barrier for the preceding rate-limiting transition state. The mechanism suggested is discussed in the context of available experimental data. An analysis of the flexibility of the F(430) cofactor during the reaction cycle is also given.

  6. MicroCommentary: A New Role for Coenzyme F420 in Aflatoxin Reduction by Soil Mycobacteria

    SciTech Connect

    Graham, David E

    2010-01-01

    Hepatotoxic aflatoxins have found a worthy adversary in two new families of bacterial oxidoreductases. These enzymes use the reduced coenzyme F420 to initiate the degradation of furanocoumarin compounds, including the major mycotoxin products of Aspergillus flavus. Along with pyridoxalamine 5 -phosphate oxidases and aryl nitroreductases, these proteins form a large and versatile superfamily of flavin and deazaflavin-dependent oxidoreductases. F420-dependent members of this family appear to share a common mechanism of hydride transfer from the reduced deazaflavin to the electron-deficient ring systems of their substrates.

  7. A Fluorescent, Reagentless Biosensor for ATP, Based on Malonyl-Coenzyme A Synthetase

    PubMed Central

    2015-01-01

    A fluorescent reagentless biosensor for ATP has been developed, based on malonyl-coenzyme A synthetase from Rhodopseudomonas palustris as the protein scaffold and recognition element. Two 5-iodoacetamidotetramethylrhodamines were covalently bound to this protein to provide the readout. This adduct couples ATP binding to a 3.7-fold increase in fluorescence intensity with excitation at 553 nm and emission at 575 nm. It measures ATP concentrations with micromolar sensitivity and is highly selective for ATP relative to ADP. Its ability to monitor enzymatic ATP production or depletion was demonstrated in steady-state kinetic assays in which ATP is a product or substrate, respectively. PMID:26355992

  8. [Reduced synthesis of coenzyme Q10 may cause statin related myopathy].

    PubMed

    Nielsen, Mette Lundgren; Pareek, Manan; Henriksen, Jan Erik

    2011-11-14

    Statin treatment can cause muscular side effects. It has been suggested that the mechanism is reduced synthesis of coenzyme Q10 (coQ10) and a subsequent dysfunction of the respiratory chain. A literature review resulted in insufficient evidence supporting this theory. It is uncertain whether intramuscular levels of coQ10 and mitochondrial function are affected by statin therapy and whether the symptoms of myopathy can be alleviated with coQ10 supplementation. Nevertheless, due to a favourable safety profile, coQ10 can be tested in patients whose muscular symptoms cannot be managed otherwise.

  9. An Improvement of Oxidative Stress in Diabetic Rats by Ubiquinone-10 and Ubiquinol-10 and Bioavailability after Short- and Long-Term Coenzyme Q10 Supplementation.

    PubMed

    Prangthip, Pattaneeya; Kettawan, Aikkarach; Posuwan, Juthathip; Okuno, Masaaki; Okamoto, Tadashi

    2016-11-01

    This study explored effects of ubiquinol-10 and ubiquinone-10, two different forms of coenzyme Q10, in diabetic rats. Oxidative stress is characterized by the depletion of antioxidant defenses and overproduction of free radicals that might contribute to, and even accelerate, the development of diabetes mellitus (DM) complications. Coenzyme Q10 was administered orally to diabetic rats and oxidative stress markers were then assessed. Bioavailability in normal rats was additionally assessed in various tissues and subcellular fractions after short-term and long-term coenzyme Q10 supplementation. Elevated nonfasting blood glucose and blood pressure in diabetic rats were decreased by ubiquinone-10. Both ubiquinol-10 and ubiquinone-10 ameliorated oxidative stress, based on assays for reactive oxygen metabolites and malondialdehyde. Coenzyme Q10 levels increased with both treatments and liver nicotinamide adenine dinucleotide phosphate (NADPH) coenzyme Q reductase with ubiquinone-10. Ubiquinol-10 was better absorbed in the liver and pancreas than ubiquinone-10, though both were similarly effective. In bioavailability study, a longer period of coenzyme Q10 supplementation did not lead to its accumulation in tissues or organelles. Both forms of coenzyme Q10 reduced oxidative stress in diabetic rats. Long-term supplementation of coenzyme Q10 appeared to be safe.

  10. [Effect of biologically active food supplement coenzyme Q10 on metabolic processes in the myocardium of rats kept in different temperature conditions].

    PubMed

    Mikashinovich, Z I; Novoderzhkina, Iu G; Belousova, E S

    2007-01-01

    In present research the action of coenzyme Q10 on energetic metabolism and antioxidant system at different temperature conditions has been studied. It was established that the addition of coenzyme Q10 caused inadequate stimulation of main metabolic systems that could lead to running out of functional reserves of cardiomyocytes. The use of coenzyme Q10 helped to optimize intracellular compensating mechanisms supplying the defense of myocardium. Introduction in a diet coenzyme Q10 in conditions of a temperature's comfort threshold excess and development of a histic hypoxia can promote the decrease of gravity of hypoxic myocardium's lesions and to glycogenolysis' amplification that promotes maintenance of an energy homeostasis of a myocardium in posthypoxia term. It is possible to assume, that the augmentation of duration of reception coenzyme Q10 or its dosages can render more expressed protective effect.

  11. One statin, two statins, three statins, more: similarities and differences of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors.

    PubMed

    Turkoski, Beatrice B

    2011-01-01

    Statin drugs (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) are one of the most widely prescribed drugs today. They are considered first-line therapy to lower blood serum cholesterol levels in conjunction with therapeutic lifestyle changes for both primary and secondary prevention of cardiovascular events. In the following discussion, a brief explanation of the background of statins will explain why they are deemed so important today. The similarities and differences between the different statins will be addressed, including a look at dosage, side effects, and cautions for the seven 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors currently available.

  12. Structural Analysis of a Ni-Methyl Species in Methyl-Coenzyme M Reductase from Methanothermobacter marburgensis

    SciTech Connect

    Cedervall, Peder E.; Dey, Mishtu; Li, Xianghui; Sarangi, Ritimukta; Hedman, Britt; Ragsdale, Stephen W.; Wilmot, Carrie M.

    2012-02-15

    We present the 1.2 {angstrom} resolution X-ray crystal structure of a Ni-methyl species that is a proposed catalytic intermediate in methyl-coenzyme M reductase (MCR), the enzyme that catalyzes the biological formation of methane. The methyl group is situated 2.1 {angstrom} proximal of the Ni atom of the MCR coenzyme F{sub 430}. A rearrangement of the substrate channel has been posited to bring together substrate species, but Ni(III)-methyl formation alone does not lead to any observable structural changes in the channel.

  13. Selenium and coenzyme Q10 interrelationship in cardiovascular diseases--A clinician's point of view.

    PubMed

    Alehagen, Urban; Aaseth, Jan

    2015-01-01

    A short review is given of the potential role of selenium deficiency and selenium intervention trials in atherosclerotic heart disease. Selenium is an essential constituent of several proteins, including the glutathione peroxidases and selenoprotein P. The selenium intake in Europe is generally in the lower margin of recommendations from authorities. Segments of populations in Europe may thus have a deficient intake that may be presented by a deficient anti-oxidative capacity in various illnesses, in particular atherosclerotic disease, and this may influence the prognosis of the disease. Ischemic heart disease and heart failure are two conditions where increased oxidative stress has been convincingly demonstrated. Some of the intervention studies of anti-oxidative substances that have focused on selenium are discussed in this review. The interrelationship between selenium and coenzyme Q10, another anti-oxidant, is presented, pointing to a theoretical advantage in using both substances in an intervention if there are deficiencies within the population. Clinical results from an intervention study using both selenium and coenzyme Q10 in an elderly population are discussed, where reduction in cardiovascular mortality, a better cardiac function according to echocardiography, and finally a lower concentration of the biomarker NT-proBNP as a sign of lower myocardial wall tension could be seen in those on active treatment, compared to placebo.

  14. Molecular characterization of methanogenic N(5)-methyl-tetrahydromethanopterin: Coenzyme M methyltransferase.

    PubMed

    Upadhyay, Vikrant; Ceh, Katharina; Tumulka, Franz; Abele, Rupert; Hoffmann, Jan; Langer, Julian; Shima, Seigo; Ermler, Ulrich

    2016-09-01

    Methanogenic archaea share one ion gradient forming reaction in their energy metabolism catalyzed by the membrane-spanning multisubunit complex N(5)-methyl-tetrahydromethanopterin: coenzyme M methyltransferase (MtrABCDEFGH or simply Mtr). In this reaction the methyl group transfer from methyl-tetrahydromethanopterin to coenzyme M mediated by cobalamin is coupled with the vectorial translocation of Na(+) across the cytoplasmic membrane. No detailed structural and mechanistic data are reported about this process. In the present work we describe a procedure to provide a highly pure and homogenous Mtr complex on the basis of a selective removal of the only soluble subunit MtrH with the membrane perturbing agent dimethyl maleic anhydride and a subsequent two-step chromatographic purification. A molecular mass determination of the Mtr complex by laser induced liquid bead ion desorption mass spectrometry (LILBID-MS) and size exclusion chromatography coupled with multi-angle light scattering (SEC-MALS) resulted in a (MtrABCDEFG)3 heterotrimeric complex of ca. 430kDa with both techniques. Taking into account that the membrane protein complex contains various firmly bound small molecules, predominantly detergent molecules, the stoichiometry of the subunits is most likely 1:1. A schematic model for the subunit arrangement within the MtrABCDEFG protomer was deduced from the mass of Mtr subcomplexes obtained by harsh IR-laser LILBID-MS.

  15. Biochemical Characterization and Complete Conversion of Coenzyme Specificity of Isocitrate Dehydrogenase from Bifidobacterium longum.

    PubMed

    Huang, Shi-Ping; Cheng, Hong-Mei; Wang, Peng; Zhu, Guo-Ping

    2016-02-26

    Bifidobacterium longum is a very important gram-positive non-pathogenic bacterium in the human gastrointestinal tract for keeping the digestive and immune system healthy. Isocitrate dehydrogenase (IDH) from B. longum (BlIDH), a novel member in Type II subfamily, was overexpressed, purified and biochemically characterized in detail. The active form of BlIDH was an 83-kDa homodimer. Kinetic analysis showed BlIDH was a NADP⁺-dependent IDH (NADP-IDH), with a 567- and 193-fold preference for NADP⁺ over NAD⁺ in the presence of Mg(2+) and Mn(2+), respectively. The maximal activity for BlIDH occurred at 60 °C (with Mn(2+)) and 65 °C (with Mg(2+)), and pH 7.5 (with Mn(2+)) and pH 8.0 (with Mg(2+)). Heat-inactivation profiles revealed that BlIDH retained 50% of maximal activity after incubation at 45 °C for 20 min with either Mn(2+) or Mg(2+). Furthermore, the coenzyme specificity of BlIDH can be completely reversed from NADP⁺ to NAD⁺ by a factor of 2387 by replacing six residues. This current work, the first report on the coenzyme specificity conversion of Type II NADP-IDHs, would provide better insight into the evolution of NADP⁺ use by the IDH family.

  16. Metal plasmon-coupled fluorescence imaging and label free coenzyme detection in cells.

    PubMed

    Zhang, Jian; Fu, Yi; Li, Ge; Zhao, Richard Y

    2012-08-31

    Flavin adenine dinucleotide (FAD) is a key metabolite in cellular energy conversion. Flavin can also bind with some enzymes in the metabolic pathway and the binding sites may be changed due to the disease progression. Thus, there is interest on studying its expression level, distribution, and redox state within the cells. FAD is naturally fluorescent, but it has a modest extinction coefficient and quantum yield. Hence the intrinsic emission from FAD is generally too weak to be isolated distinctly from the cellular backgrounds in fluorescence cell imaging. In this article, the metal nanostructures on the glass coverslips were used as substrates to measure FAD in cells. Particulate silver films were fabricated with an optical resonance near the absorption and the emission wavelengths of FAD which can lead to efficient coupling interactions. As a result, the emission intensity and quantum yield by FAD were greatly increased and the lifetime was dramatically shortened resulting in less interference from the longer lived cellular background. This feature may overcome the technical limits that hinder the direct observation of intrinsically fluorescent coenzymes in the cells by fluorescence microscopy. Fluorescence cell imaging on the metallic particle substrates may provide a non-invasive strategy for collecting the information of coenzymes in cells.

  17. Computational design of short-chain dehydrogenase Gox2181 for altered coenzyme specificity.

    PubMed

    Cui, Dongbing; Zhang, Lujia; Zhang, Lujiang; Yao, Zhiqiang; Liu, Xu; Lin, Jinping; Yuan, Y Adam; Wei, Dongzhi

    2013-09-20

    Short-chain dehydrogenase Gox2181 from Gluconobacter oxydans catalyzes the reduction of 2,3-pentanedione by using NADH as the physiological electron donor. To realize its synthetic biological application for coenzyme recycling use, computational design and site-directed mutagenesis have been used to engineer Gox2181 to utilize not only NADH but also NADPH as the electron donor. Single and double mutations at residues Q20 and D43 were made in a recombinant expression system that corresponded to Gox2181-D43Q and Gox2181-Q20R&D43Q, respectively. The design of mutant Q20R not only resolved the hydrogen bond interaction and electrostatic interaction between R and 2'-phosphate of NADPH, but also could enhance the binding with 2'-phophated of NADPH by combining with D43Q. Molecular dynamics simulation has been carried out to testify the hydrogen bond interactions between mutation sites and 2'-phosphate of NADPH. Steady-state turnover measurement results indicated that Gox2181-D43Q could use both NADH and NADPH as its coenzyme, and so could Gox2181-Q20R&D43Q. Meanwhile, compared to the wild-type enzyme, Gox2181-D43Q exhibited dramatically reduced enzymatic activity while Gox2181-Q20R&D43Q successfully retained the majority of enzymatic activity.

  18. Probing Reversible Chemistry in Coenzyme B12-Dependent Ethanolamine Ammonia Lyase with Kinetic Isotope Effects

    PubMed Central

    Jones, Alex R; Rentergent, Julius; Scrutton, Nigel S; Hay, Sam

    2015-01-01

    Coenzyme B12-dependent enzymes such as ethanolamine ammonia lyase have remarkable catalytic power and some unique properties that enable detailed analysis of the reaction chemistry and associated dynamics. By selectively deuterating the substrate (ethanolamine) and/or the β-carbon of the 5′-deoxyadenosyl moiety of the intrinsic coenzyme B12, it was possible to experimentally probe both the forward and reverse hydrogen atom transfers between the 5′-deoxyadenosyl radical and substrate during single-turnover stopped-flow measurements. These data are interpreted within the context of a kinetic model where the 5′-deoxyadenosyl radical intermediate may be quasi-stable and rearrangement of the substrate radical is essentially irreversible. Global fitting of these data allows estimation of the intrinsic rate constants associated with CoC homolysis and initial H-abstraction steps. In contrast to previous stopped-flow studies, the apparent kinetic isotope effects are found to be relatively small. PMID:25950663

  19. A highly convergent synthesis of myristoyl-carba(dethia)-coenzyme A

    PubMed Central

    Tautz, Lutz; Rétey, Janos

    2012-01-01

    Co-translational myristoylation of the N-terminal glycine residue of diverse signaling proteins is required for membrane attachment and proper function of these molecules. The transfer of myristate from myristoyl-coenzyme A (myr-CoA) is catalyzed by the enzyme N-myristoyltransferase (Nmt). Nmt has been implicated in a number of human diseases, including cancer and epilepsy, as well as pathogenic mechanisms such as fungal and virus infections, including HIV and Hepatitis B. Rational design has led to the development of potent competitive inhibitors, including several non-hydrolysable acyl-CoA substrate analogues. However, linear synthetic strategies, following the route of the original CoA synthesis, generate such analogues in very low over all yields that typically are not sufficient for in vivo studies. Here, we present a new, highly convergent synthesis of myristoyl-carba(dethia)-coenzyme A 1 that allows to obtain this substrate analogue in 11-fold increased yield compared to the reported linear synthesis. In addition, enzymatic cleavage of the adenosine-2',3'-cyclophosphate in the last step of the synthesis proved to be an efficient way to obtain the isomerically pure 3'-phosphate 1. PMID:22347809

  20. A highly convergent synthesis of myristoyl-carba(dethia)-coenzyme A.

    PubMed

    Tautz, Lutz; Rétey, Janos

    2010-03-01

    Co-translational myristoylation of the N-terminal glycine residue of diverse signaling proteins is required for membrane attachment and proper function of these molecules. The transfer of myristate from myristoyl-coenzyme A (myr-CoA) is catalyzed by the enzyme N-myristoyltransferase (Nmt). Nmt has been implicated in a number of human diseases, including cancer and epilepsy, as well as pathogenic mechanisms such as fungal and virus infections, including HIV and Hepatitis B. Rational design has led to the development of potent competitive inhibitors, including several non-hydrolysable acyl-CoA substrate analogues. However, linear synthetic strategies, following the route of the original CoA synthesis, generate such analogues in very low over all yields that typically are not sufficient for in vivo studies. Here, we present a new, highly convergent synthesis of myristoyl-carba(dethia)-coenzyme A 1 that allows to obtain this substrate analogue in 11-fold increased yield compared to the reported linear synthesis. In addition, enzymatic cleavage of the adenosine-2',3'-cyclophosphate in the last step of the synthesis proved to be an efficient way to obtain the isomerically pure 3'-phosphate 1.

  1. Metabolic consequences of mitochondrial coenzyme A deficiency in patients with PANK2 mutations.

    PubMed

    Leoni, Valerio; Strittmatter, Laura; Zorzi, Giovanna; Zibordi, Federica; Dusi, Sabrina; Garavaglia, Barbara; Venco, Paola; Caccia, Claudio; Souza, Amanda L; Deik, Amy; Clish, Clary B; Rimoldi, Marco; Ciusani, Emilio; Bertini, Enrico; Nardocci, Nardo; Mootha, Vamsi K; Tiranti, Valeria

    2012-03-01

    Pantothenate kinase-associated neurodegeneration (PKAN) is a rare, inborn error of metabolism characterized by iron accumulation in the basal ganglia and by the presence of dystonia, dysarthria, and retinal degeneration. Mutations in pantothenate kinase 2 (PANK2), the rate-limiting enzyme in mitochondrial coenzyme A biosynthesis, represent the most common genetic cause of this disorder. How mutations in this core metabolic enzyme give rise to such a broad clinical spectrum of pathology remains a mystery. To systematically explore its pathogenesis, we performed global metabolic profiling on plasma from a cohort of 14 genetically defined patients and 18 controls. Notably, lactate is elevated in PKAN patients, suggesting dysfunctional mitochondrial metabolism. As predicted, but never previously reported, pantothenate levels are higher in patients with premature stop mutations in PANK2. Global metabolic profiling and follow-up studies in patient-derived fibroblasts also reveal defects in bile acid conjugation and lipid metabolism, pathways that require coenzyme A. These findings raise a novel therapeutic hypothesis, namely, that dietary fats and bile acid supplements may hold potential as disease-modifying interventions. Our study illustrates the value of metabolic profiling as a tool for systematically exploring the biochemical basis of inherited metabolic diseases.

  2. Reversal of statin-induced memory dysfunction by co-enzyme Q10: a case report

    PubMed Central

    Okeahialam, Basil N

    2015-01-01

    Statins are useful in the armamentarium of the clinician dealing with dyslipidemia, which increases cardiovascular morbi-mortality in hypertensive and diabetic patients among others. Dyslipidemia commonly exists as a comorbidity factor in the development of atherosclerotic cardiovascular disease. Use of statins is however associated with side effects which at times are so disabling as to interfere with activities of daily living. There are various ways of dealing with this, including use of more water-soluble varieties, intermittent dosing, or use of statin alternatives. Of late, use of co-enzyme Q10 has become acceptable for the muscle side effects. Only one report of any benefit on the rarely reported memory side effect was encountered by the author in the search of English medical literature. This is a report of a documented case of a Nigerian woman with history of statin intolerance in this case, memory dysfunction despite persisting dyslipidemia comorbidity. Her memory dysfunction side effect which interfered with activities of daily living and background muscle pain cleared when coenzyme Q10 was administered alongside low dose statin. Her lipid profile normalized and has remained normal. It is being recommended for use when statin side effects (muscle- and memory-related) impair quality of life and leave patient at dyslipidemia-induced cardiovascular morbi-mortality. PMID:26604775

  3. Homocysteine Editing, Thioester Chemistry, Coenzyme A, and the Origin of Coded Peptide Synthesis †.

    PubMed

    Jakubowski, Hieronim

    2017-02-09

    Aminoacyl-tRNA synthetases (AARSs) have evolved "quality control" mechanisms which prevent tRNA aminoacylation with non-protein amino acids, such as homocysteine, homoserine, and ornithine, and thus their access to the Genetic Code. Of the ten AARSs that possess editing function, five edit homocysteine: Class I MetRS, ValRS, IleRS, LeuRS, and Class II LysRS. Studies of their editing function reveal that catalytic modules of these AARSs have a thiol-binding site that confers the ability to catalyze the aminoacylation of coenzyme A, pantetheine, and other thiols. Other AARSs also catalyze aminoacyl-thioester synthesis. Amino acid selectivity of AARSs in the aminoacyl thioesters formation reaction is relaxed, characteristic of primitive amino acid activation systems that may have originated in the Thioester World. With homocysteine and cysteine as thiol substrates, AARSs support peptide bond synthesis. Evolutionary origin of these activities is revealed by genomic comparisons, which show that AARSs are structurally related to proteins involved in coenzyme A/sulfur metabolism and non-coded peptide bond synthesis. These findings suggest that the extant AARSs descended from ancestral forms that were involved in non-coded Thioester-dependent peptide synthesis, functionally similar to the present-day non-ribosomal peptide synthetases.

  4. Plasma coenzyme Q10 levels in type 2 diabetic patients with retinopathy

    PubMed Central

    Ates, Orhan; Bilen, Habip; Keles, Sadullah; Alp, H. Hakan; Keleş, Mevlüt Sait; Yıldırım, Kenan; Öndaş, Osman; Pınar, L. Can; Civelekler, Mustafa; Baykal, Orhan

    2013-01-01

    AIM To determine the relationship between proliferative diabetic retinopathy (PDRP) and plasma coenzyme Q10(CoQ10) concentration. METHODS Patients with type 2 diabetes and PDRP were determined to be the case group (n=50). The control group was consist of healthy individuals (n=50). Plasma CoQ10 and malondialdehyde (MDA) levels were measured in both groups. RESULTS Ubiquinone-10 (Coenzyme Q10) levels in PDRP and control subjects are 3.81±1.19µmol/L and 1.91±0.62µmol/L, respectively. Plasma MDA levels in PDRP and control subjects were 8.16±2µmol/L and 3.44±2.08µmol/L, respectively. Ratio of Ubiquinol-10/ubiquinone-10 in PDRP and control subjects were 0.26±0.16 and 1.41±0.68, respectively. CONCLUSION The ratio of ubiquinol-10/ubiquinone-10 is found lower in patients with PDRP. High levels of plasma ubiquinol-10/ubiquinone-10 ratio indicate the protective effect on diabetic retinopathy. PMID:24195048

  5. Inhibition of acetyl-coenzyme A carboxylase by two classes of grass-selective herbicides

    SciTech Connect

    Rendina, A.R.; Craig-Kennard, A.C.; Beaudoin, J.D.; Breen, M.K. )

    1990-05-01

    The selective grass herbicides diclofop, haloxyfop, and trifop (((aryloxy)phenoxy)propionic acids) and alloxydim, sethoxydim, and clethodim (cyclohexanediones) are potent, reversible inhibitors of acetyl-coenzyme A carboxylase (ACC) partially purified from barley, corn, and wheat. Although inhibition of the wheat enzyme by clethodim and diclofop is noncompetitive versus each of the substrates adenosine triphosphate (ATP), HCO{sub 3}{sup {minus}}, and acetyl-coenzyme A (acetyl-CoA), diclofop and clethodim are nearly competitive versus acetyl-CoA since the level of inhibition is most sensitive to the concentration of acetyl-CoA (K{sub is} < K{sub ii}). To conclusively show whether the herbicides interact at the biotin carboxylation site or the carboxyl transfer site, the inhibition of isotope exchange and partial reactions catalyzed at each site was studied with the wheat enzyme. Only the ({sup 14}C)acetyl-CoA-malonyl-CoA exchange and decarboxylation of ({sup 14}C)malonyl-CoA reactions are strongly inhibited by clethodim and diclofop, suggesting that the herbicides interfere with the carboxyl transfer site rather than the biotin carboxylation site of the enzyme. Double-inhibition studies with diclofop and clethodim suggest that the ((aryloxy)phenoxy)propionic acid and cyclohexanedione herbicides may bind to the same region of the enzyme.

  6. New insights into the chemistry of Coenzyme Q-0: A voltammetric and spectroscopic study.

    PubMed

    Gulaboski, Rubin; Bogeski, Ivan; Kokoskarova, Pavlinka; Haeri, Haleh H; Mitrev, Sasa; Stefova, Marina; Stanoeva, Jasmina Petreska; Markovski, Velo; Mirčeski, Valentin; Hoth, Markus; Kappl, Reinhard

    2016-10-01

    Coenzyme Q-0 (CoQ-0) is the only Coenzyme Q lacking an isoprenoid group on the quinoid ring, a feature important for its physico-chemical properties. Here, the redox behavior of CoQ-0 in buffered and non-buffered aqueous media was examined. In buffered aqueous media CoQ-0 redox chemistry can be described by a 2-electron-2-proton redox scheme, characteristic for all benzoquinones. In non-buffered media the number of electrons involved in the electrode reaction of CoQ-0 is still 2; however, the number of protons involved varies between 0 and 2. This results in two additional voltammetric signals, attributed to 2-electrons-1H(+) and 2-electrons-0H(+) redox processes, in which mono- and di-anionic compounds of CoQ-0 are formed. In addition, CoQ-0 exhibits a complex chemistry in strong alkaline environment. The reaction of CoQ-0 and OH(-) anions generates several hydroxyl derivatives as products. Their structures were identified with HPLC/MS. The prevailing radical reaction mechanism was analyzed by electron paramagnetic resonance spectroscopy. The hydroxyl derivatives of CoQ-0 have a strong antioxidative potential and form stable complexes with Ca(2+) ions. In summary, our results allow mechanistic insights into the redox properties of CoQ-0 and its hydroxylated derivatives and provide hints on possible applications.

  7. Homocysteine Editing, Thioester Chemistry, Coenzyme A, and the Origin of Coded Peptide Synthesis †

    PubMed Central

    Jakubowski, Hieronim

    2017-01-01

    Aminoacyl-tRNA synthetases (AARSs) have evolved “quality control” mechanisms which prevent tRNA aminoacylation with non-protein amino acids, such as homocysteine, homoserine, and ornithine, and thus their access to the Genetic Code. Of the ten AARSs that possess editing function, five edit homocysteine: Class I MetRS, ValRS, IleRS, LeuRS, and Class II LysRS. Studies of their editing function reveal that catalytic modules of these AARSs have a thiol-binding site that confers the ability to catalyze the aminoacylation of coenzyme A, pantetheine, and other thiols. Other AARSs also catalyze aminoacyl-thioester synthesis. Amino acid selectivity of AARSs in the aminoacyl thioesters formation reaction is relaxed, characteristic of primitive amino acid activation systems that may have originated in the Thioester World. With homocysteine and cysteine as thiol substrates, AARSs support peptide bond synthesis. Evolutionary origin of these activities is revealed by genomic comparisons, which show that AARSs are structurally related to proteins involved in coenzyme A/sulfur metabolism and non-coded peptide bond synthesis. These findings suggest that the extant AARSs descended from ancestral forms that were involved in non-coded Thioester-dependent peptide synthesis, functionally similar to the present-day non-ribosomal peptide synthetases. PMID:28208756

  8. Relaxing the coenzyme specificity of 1,3-propanediol oxidoreductase from Klebsiella pneumoniae by rational design.

    PubMed

    Ma, Chengwei; Zhang, Le; Dai, Jianying; Xiu, Zhilong

    2010-04-15

    1,3-Propanediol has wide applications for large volume markets, particularly in the polymer business. Microbial production of 1,3-propanediol has been considered as a competitor to the traditional petrochemical routes. However, the formation of 1,3-propanediol is limited by the amount of NADH supplied by the oxidative pathway of glycerol dismutation. Previous metabolic flux analysis revealed that relaxation of the coenzyme specificity of 1,3-propanediol oxidoreductase for both NADH and NADPH would increase the production of 1,3-propanediol as well as maintaining the NADH-NAD(+) circle. This work tried to accomplish such a relaxation by rational protein design. Overall binding free energy indicated that the electrostatic energy was the major force discriminating NADH from NADPH. Computational alanine-scanning mutagenesis of the active site residues illustrated that Asp41 was the key residue responsible for the coenzyme specificity. Compared with Asp41Ala, Asp41Gly could further weaken the repulsion between Asp41 and the phosphate group esterified to the 2'-hydroxyl group of the ribose at the adenine end of NADPH. Site-directed mutagenesis was conducted and the relaxation was successfully realized.

  9. High-resolution neutron crystallographic studies of the hydration of the coenzyme cob(II)alamin

    SciTech Connect

    Jogl, Gerwald; Wang, Xiaoping; Mason, Sax A.; Kovalevsky, Andrey; Mustyakimov, Marat; Fisher, Zöe; Hoffman, Christina; Kratky, Christoph; Langan, Paul

    2011-06-01

    High-resolution crystallographic studies of the hydration of the coenzyme cob(II)alamin have provided hydrogen-bond parameters of unprecedented accuracy for a biomacromolecule. The hydration of the coenzyme cob(II)alamin has been studied using high-resolution monochromatic neutron crystallographic data collected at room temperature to a resolution of 0.92 Å on the original D19 diffractometer with a prototype 4° × 64° detector at the high-flux reactor neutron source run by the Institute Laue–Langevin. The resulting structure provides hydrogen-bonding parameters for the hydration of biomacromolecules to unprecedented accuracy. These experimental parameters will be used to define more accurate force fields for biomacromolecular structure refinement. The presence of a hydrophobic bowl motif surrounded by flexible side chains with terminal functional groups may be significant for the efficient scavenging of ligands. The feasibility of extending the resolution of this structure to ultrahigh resolution was investigated by collecting time-of-flight neutron crystallographic data during commissioning of the TOPAZ diffractometer with a prototype array of 14 modular 2° × 21° detectors at the Spallation Neutron Source run by Oak Ridge National Laboratory.

  10. Metabolic consequences of mitochondrial coenzyme A deficiency in patients with PANK2 mutations

    PubMed Central

    Leoni, Valerio; Strittmatter, Laura; Zorzi, Giovanna; Zibordi, Federica; Dusi, Sabrina; Garavaglia, Barbara; Venco, Paola; Caccia, Claudio; Souza, Amanda L; Deik, Amy; Clish, Clary B; Rimoldi, Marco; Ciusani, Emilio; Bertini, Enrico; Nardocci, Nardo; Mootha, Vamsi K; Tiranti, Valeria

    2012-01-01

    Pantothenate kinase-associated neurodegeneration (PKAN) is a rare, inborn error of metabolism characterized by iron accumulation in the basal ganglia and by the presence of dystonia, dysarthria, and retinal degeneration. Mutations in pantothenate kinase 2 (PANK2), the rate-limiting enzyme in mitochondrial coenzyme A biosynthesis, represent the most common genetic cause of this disorder. How mutations in this core metabolic enzyme give rise to such a broad clinical spectrum of pathology remains a mystery. To systematically explore its pathogenesis, we performed global metabolic profiling on plasma from a cohort of 14 genetically defined patients and 18 controls. Notably, lactate is elevated in PKAN patients, suggesting dysfunctional mitochondrial metabolism. As predicted, but never previously reported, pantothenate levels are higher in patients with premature stop mutations in PANK2. Global metabolic profiling and follow-up studies in patient-derived fibroblasts also reveal defects in bile acid conjugation and lipid metabolism, pathways that require coenzyme A. These findings raise a novel therapeutic hypothesis, namely, that dietary fats and bile acid supplements may hold potential as disease-modifying interventions. Our study illustrates the value of metabolic profiling as a tool for systematically exploring the biochemical basis of inherited metabolic diseases. PMID:22221393

  11. Production of a Brassica napus low-molecular mass acyl-coenzyme A-binding protein in Arabidopsis alters the acyl-coenzyme A pool and acyl composition of oil in seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low-molecular mass (10 kD) cytosolic acyl-coenzyme A-binding protein (ACBP) has a substantial influence over fatty acid (FA) composition in oilseeds, possibly via an effect on the partitioning of acyl groups between elongation and desaturation pathways. Previously, we demonstrated that the expressio...

  12. Genome Sequence of the Fungal Strain 14919 Producing 3-Hydroxy-3-Methylglutaryl–Coenzyme A Reductase Inhibitor FR901512

    PubMed Central

    Matsui, Makoto; Kumagai, Toshitaka; Arita, Masanori; Machida, Masayuki; Shibata, Takashi

    2017-01-01

    ABSTRACT Fungal strain 14919 was originally isolated from a soil sample collected at Mt. Kiyosumi, Chiba Prefecture, Japan. It produces FR901512, a potent and strong 3-hydroxy-3-methylglutaryl–coenzyme A (HMG-CoA) reductase inhibitor. The genome sequence of fungal strain 14919 was determined and annotated to improve the productivity of FR901512. PMID:28385847

  13. 77 FR 60722 - Certain Coenzyme Q10 Products and Methods of Making Same; Notice of Request for Statements on the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-04

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Certain Coenzyme Q10 Products and Methods of Making Same; Notice of Request for Statements on the Public Interest AGENCY: U.S. International Trade Commission. ACTION: Notice. SUMMARY: Notice is...

  14. Regulation of 4CL, encoding 4-coumarate: coenzyme A ligase, expression in kenaf under diverse stress conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We cloned the full length 4CL ortholog encoding 4-coumarate: coenzymeA ligase from kenaf (Hibiscus cannabiuns) using degenerate primers and RACE (rapid amplification of cDNA ends) systems. The 4CL is a key regulatory enzyme of the phenylpropanoid pathway that regulates the activation of cinnamic ac...

  15. Absence of malonyl coenzyme A decarboxylase in mice increases cardiac glucose oxidation and protects the heart from ischemic injury

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acute pharmacological inhibition of cardiac malonyl coenzyme A decarboxylase (MCD) protects the heart from ischemic damage by inhibiting fatty acid oxidation and stimulating glucose oxidation. However, it is unknown whether chronic inhibition of MCD results in altered cardiac function, energy metabo...

  16. Quantitative description of the absorption spectra of the coenzyme in glycogen phosphorylases based on log-normal distribution curves.

    PubMed Central

    Donoso, J; Muñoz, F; Garcia Blanco, F

    1993-01-01

    The absorption spectra of the coenzyme [pyridoxal 5'-phosphate (PLP)] in glycogen phosphorylase a (GPha), glycogen phosphorylase b (GPhb) and of the latter bound to various effectors and substrates were analysed on the basis of log-normal distribution curves. The results obtained showed that the ionization state of the PLP and GPha environment differs from that of GPhb. This divergence was interpreted in terms of tautomeric equilibria between some forms of the Schiff base of PLP and enzymic Lys-679. The ionic forms are slightly more predominant in GPha than they are in GPhb, so ionic and/or hydrogen-bonding interactions between the aromatic ring of PLP and GPha must be stronger than with GPhb. This confirms the purely structural role of the aromatic ring of the coenzyme. Binding of GPhb to AMP and Mg2+ results in the coenzyme adopting a similar state as in GPha. On the other hand, binding to IMP gives rise to no detectable changes in the tautomeric equilibrium of the coenzyme. PMID:8503849

  17. Lithium carbonate and coenzyme Q10 reduce cell death in a cell model of Machado-Joseph disease

    PubMed Central

    Lopes-Ramos, C.M.; Pereira, T.C.; Dogini, D.B.; Gilioli, R.; Lopes-Cendes, I.

    2016-01-01

    Machado-Joseph disease (MJD) or spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant neurodegenerative disorder caused by expansion of the polyglutamine domain of the ataxin-3 (ATX3) protein. MJD/SCA3 is the most frequent autosomal dominant ataxia in many countries. The mechanism underlying MJD/SCA3 is thought to be mainly related to protein misfolding and aggregation leading to neuronal dysfunction followed by cell death. Currently, there are no effective treatments for patients with MJD/SCA3. Here, we report on the potential use of lithium carbonate and coenzyme Q10 to reduce cell death caused by the expanded ATX3 in cell culture. Cell viability and apoptosis were evaluated by MTT assay and by flow cytometry after staining with annexin V-FITC/propidium iodide. Treatment with lithium carbonate and coenzyme Q10 led to a significant increase in viability of cells expressing expanded ATX3 (Q84). In addition, we found that the increase in cell viability resulted from a significant reduction in the proportion of apoptotic cells. Furthermore, there was a significant change in the expanded ATX3 monomer/aggregate ratio after lithium carbonate and coenzyme Q10 treatment, with an increase in the monomer fraction and decrease in aggregates. The safety and tolerance of both drugs are well established; thus, our results indicate that lithium carbonate and coenzyme Q10 are good candidates for further in vivo therapeutic trials. PMID:27878228

  18. Amelioratory effect of coenzyme Q10 on potential human carcinogen Microcystin-LR induced toxicity in mice.

    PubMed

    Lone, Yaqoob; Bhide, Mangla; Koiri, Raj Kumar

    2017-04-01

    Microcystins are a group of cyclic heptapeptide toxins produced by cyanobacteria. More than 100 microcystin analogues have been detected, among which microcystin-LR is the most abundant and toxic variant. Present study was designed to reveal whether potential human carcinogen microcystin-LR could imbalance the glycolytic-oxidative-nitrosative status of heart, kidney and spleen of mice and also to explore the amelioratory effect of coenzyme Q10 on microcystin-LR induced toxicity. Microcystin-LR was administered at a dose of 10 μg/kg bw/day, ip for 14 days in male mice. In microcystin-LR treated mice as compared to control, significant increase in the level of lipid peroxidation, hydrogen peroxide, lactate dehydrogenase, nitric oxide with a concomitant decrease in the level of glutathione was observed, suggesting microcystin-LR induced toxicity via induction of oxidative-nitrosative-glycolytic pathway. Although several studies have evaluated numerous antioxidants but still there is no effective chemoprotectant against microcystin-LR induced toxicity. When microcystin-LR treated mice were co-administered coenzyme Q10 (10 mg/kg bw/day, im) for 14 days, it was observed that coenzyme Q10 ameliorates microcystin-LR induced toxicity via modulation of glycolytic-oxidative-nitrosative stress pathway. Thus, the results suggest that coenzyme Q10 has a potential to be developed as preventive agent against microcystin-LR induced toxicity.

  19. Validation of CoaBC as a Bactericidal Target in the Coenzyme A Pathway of Mycobacterium tuberculosis

    PubMed Central

    2016-01-01

    Mycobacterium tuberculosis relies on its own ability to biosynthesize coenzyme A to meet the needs of the myriad enzymatic reactions that depend on this cofactor for activity. As such, the essential pantothenate and coenzyme A biosynthesis pathways have attracted attention as targets for tuberculosis drug development. To identify the optimal step for coenzyme A pathway disruption in M. tuberculosis, we constructed and characterized a panel of conditional knockdown mutants in coenzyme A pathway genes. Here, we report that silencing of coaBC was bactericidal in vitro, whereas silencing of panB, panC, or coaE was bacteriostatic over the same time course. Silencing of coaBC was likewise bactericidal in vivo, whether initiated at infection or during either the acute or chronic stages of infection, confirming that CoaBC is required for M. tuberculosis to grow and persist in mice and arguing against significant CoaBC bypass via transport and assimilation of host-derived pantetheine in this animal model. These results provide convincing genetic validation of CoaBC as a new bactericidal drug target. PMID:27676316

  20. The Impact of Coenzyme Q[subscript10] Supplement on the Indicators of Muscle Damage in Young Male Skiing Athletes

    ERIC Educational Resources Information Center

    Demirci, Nevzat

    2015-01-01

    This study was conducted in order to know the impact of coenzyme Q[subscript 10] (CoQ[subscript 10]) supplement on the muscle damage and total oxidant (TOS) enzyme levels of young skiing athletes during exercise. 15 male athletes were used for two weeks in the study. The athletes were divided into three groups: the control group and two subject…

  1. Lithium carbonate and coenzyme Q10 reduce cell death in a cell model of Machado-Joseph disease.

    PubMed

    Lopes-Ramos, C M; Pereira, T C; Dogini, D B; Gilioli, R; Lopes-Cendes, I

    2016-11-21

    Machado-Joseph disease (MJD) or spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant neurodegenerative disorder caused by expansion of the polyglutamine domain of the ataxin-3 (ATX3) protein. MJD/SCA3 is the most frequent autosomal dominant ataxia in many countries. The mechanism underlying MJD/SCA3 is thought to be mainly related to protein misfolding and aggregation leading to neuronal dysfunction followed by cell death. Currently, there are no effective treatments for patients with MJD/SCA3. Here, we report on the potential use of lithium carbonate and coenzyme Q10 to reduce cell death caused by the expanded ATX3 in cell culture. Cell viability and apoptosis were evaluated by MTT assay and by flow cytometry after staining with annexin V-FITC/propidium iodide. Treatment with lithium carbonate and coenzyme Q10 led to a significant increase in viability of cells expressing expanded ATX3 (Q84). In addition, we found that the increase in cell viability resulted from a significant reduction in the proportion of apoptotic cells. Furthermore, there was a significant change in the expanded ATX3 monomer/aggregate ratio after lithium carbonate and coenzyme Q10 treatment, with an increase in the monomer fraction and decrease in aggregates. The safety and tolerance of both drugs are well established; thus, our results indicate that lithium carbonate and coenzyme Q10 are good candidates for further in vivo therapeutic trials.

  2. Purification and Characterization of a Novel Pumpkin Short-Chain Acyl-Coenzyme A Oxidase with Structural Similarity to Acyl-Coenzyme A Dehydrogenases

    PubMed Central

    De Bellis, Luigi; Gonzali, Silvia; Alpi, Amedeo; Hayashi, Hiroshi; Hayashi, Makoto; Nishimura, Mikio

    2000-01-01

    A novel pumpkin (Cucurbita pepo) short-chain acyl-coenzyme A (CoA) oxidase (ACOX) was purified to homogeneity by hydrophobic-interaction, hydroxyapatite, affinity, and anion-exchange chromatography. The purified enzyme is a tetrameric protein, consisting of apparently identical 47-kD subunits. The protein structure of this oxidase differs from other plant and mammalian ACOXs, but is similar to the protein structure of mammalian mitochondrial acyl-CoA dehydrogenase (ACDH) and the recently identified plant mitochondrial ACDH. Subcellular organelle separation by sucrose density gradient centrifugation revealed that the enzyme is localized in glyoxysomes, whereas no immunoreactive bands of similar molecular weight were detected in mitochondrial fractions. The enzyme selectively catalyzes the oxidation of CoA esters of fatty acids with 4 to 10 carbon atoms, and exhibits the highest activity on C-6 fatty acids. Apparently, the enzyme has no activity on CoA esters of branched-chain or dicarboxylic fatty acids. The enzyme is slightly inhibited by high concentrations of substrate and it is not inhibited by Triton X-100 at concentrations up to 0.5% (v/v). The characteristics of this novel ACOX enzyme are discussed in relation to other ACOXs and ACDHs. PMID:10806249

  3. Trp(359) regulates flavin thermodynamics and coenzyme selectivity in Mycobacterium tuberculosis FprA.

    PubMed

    Neeli, Rajasekhar; Sabri, Muna; McLean, Kirsty J; Dunford, Adrian J; Scrutton, Nigel S; Leys, David; Munro, Andrew W

    2008-05-01

    Mtb (Mycobacterium tuberculosis) FprA (flavoprotein reductase A) is an NAD(P)H-dependent FAD-binding reductase that is structurally related to mammalian adrenodoxin reductase, and which supports the catalytic function of Mtb cytochrome P450s. Trp(359), proximal to the FAD, was investigated in light of its potential role in controlling coenzyme interactions, as observed for similarly located aromatic residues in diflavin reductases. Phylogenetic analysis indicated that a tryptophan residue corresponding to Trp(359) is conserved across FprA-type enzymes and in adrenodoxin reductases. W359A/H mutants of Mtb FprA were generated, expressed and the proteins characterized to define the role of Trp(359). W359A/H mutants exhibited perturbed UV-visible absorption/fluorescence properties. The FAD semiquinone formed in wild-type NADPH-reduced FprA was destabilized in the W359A/H mutants, which also had more positive FAD midpoint reduction potentials (-168/-181 mV respectively, versus the standard hydrogen electrode, compared with -230 mV for wild-type FprA). The W359A/H mutants had lower ferricyanide reductase k(cat) and NAD(P)H K(m) values, but this led to improvements in catalytic efficiency (k(cat)/K(m)) with NADH as reducing coenzyme (9.6/18.8 muM(-1).min(-1) respectively, compared with 5.7 muM(-1).min(-1) for wild-type FprA). Stopped-flow spectroscopy revealed NAD(P)H-dependent FAD reduction as rate-limiting in steady-state catalysis, and to be retarded in mutants (e.g. limiting rate constants for NADH-dependent FAD reduction were 25.4 s(-1) for wild-type FprA and 4.8 s(-1)/13.4 s(-1) for W359A/H mutants). Diminished mutant FAD content (particularly in W359H FprA) highlighted the importance of Trp(359) for flavin stability. The results demonstrate that the conserved Trp(359) is critical in regulating FprA FAD binding, thermodynamic properties, catalytic efficiency and coenzyme selectivity.

  4. Ultra-fast simultaneous detection of obesity-related coenzymes in mice using microchip electrophoresis with a LIF detector.

    PubMed

    Lee, Hee Gu; Kumar, K S; Soh, Ju-Ryoun; Cha, Youn-Soo; Kang, Seong Ho

    2008-06-30

    Hepatic acyl-coenzyme A synthetase (ACS), carnitine palmitoyltransferase-I (CPT-I) and acetyl coenzyme A carboxylase (ACC) are coenzymes associated with the genetic type of obesity in animal models. This paper reports the use of microchip electrophoresis (ME) with a laser-induced fluorescence (LIF) detector based on a reverse transcriptase-polymerase chain reaction (RT-PCR) to detect the amplified DNA fragments of these coenzymes (ACS, CPT-I and ACC) in the mRNA extracted from mice. DNA fragments ranging from 50 to 2652 bp were well resolved using this procedure with a running buffer (1x TBE), 0.5% polyvinylpyrrolidone (M(r) 1,000,000) as the coating gel and 0.7% polyethyleneoxide (M(r) 8,000,000) as the sieving gel at pH 8.30. The separation of the three RT-PCR products was achieved by ME in a single-run within 17 s using programmed field strength gradients (PFSG) (470 V cm(-1) for 9 s, 205.8 V cm(-1) for 2 s, 411.6 V cm(-1) for 4 s, 117.6 V cm(-1) for 2 s and 470.4V cm(-1) for 8 s). The ME-PFSG method was found to be 4 times faster than the method using a constant field and 138 times faster than slab gel electrophoresis. Moreover, the amplified RT-PCR products of the obesity-related coenzymes in C57BL/6J mice were analyzed using only sub-micro liter samples.

  5. L-Carnitine, but not coenzyme Q10, enhances the anti-osteoporotic effect of atorvastatin in ovariectomized rats

    PubMed Central

    Murad, Hussam A. S.

    2016-01-01

    Objective: Statins’ therapy in osteoporosis can aggravate muscle damage. This study was designed to assess which agent, L-carnitine or coenzyme Q10, could enhance the anti-osteoporotic effect of atorvastatin while antagonizing myopathy in ovariectomized rats. Methods: Forty-eight female Sprague Dawley rats were used; forty rats were ovariectomized while eight were sham-operated. Eight weeks post-ovariectomy, rats were divided into ovariectomized-untreated group and four ovariectomized-treated groups (n=8) which received by gavage (mg/(kg∙d), for 8 weeks) 17β-estradiol (0.1), atorvastatin (50), atorvastatin (50)+L-carnitine (100), or atorvastatin (50)+coenzyme Q10 (20). At the end of therapy, bone mineral density (BMD), bone mineral content (BMC), and serum levels of bone metabolic markers (BMMs) and creatine kinase (CK) were measured. Femurs were used for studying the breaking strength and histopathological changes. Results: Treatment with atorvastatin+L-carnitine restored BMD, BMC, and bone strength to near normal levels. Estrogen therapy restored BMD and BMC to near normal levels, but failed to increase bone strength. Although atorvastatin and atorvastatin+coenzyme Q10 improved BMD, BMC, and bone strength, they failed to restore levels to normal. All treatments decreased BMMs and improved histopathological changes maximally with atorvastatin+L-carnitine which restored levels to near normal. Atorvastatin aggravated the ovariectomy-induced increase in CK level while estrogen, atorvastatin+L-carnitine, and atorvastatin+coenzyme Q10 decreased its level mainly with atorvastatin+L-carnitine which restored the level to near normal. Conclusions: Co-administration of L-carnitine, but not coenzyme Q10, enhances the anti-osteoporotic effect of atorvastatin while antagonizing myopathy in ovariectomized rats. This could be valuable in treatment of osteoporotic patients. However, further confirmatory studies are needed. PMID:26739525

  6. Antiatherogenic, hepatoprotective, and hypolipidemic effects of coenzyme Q10 in alloxan-induced type 1 diabetic rats

    PubMed Central

    Ahmadvand, Hassan; Ghasemi-Dehnoo, Maryam

    2014-01-01

    BACKGROUND Diabetes mellitus, one of the leading metabolic syndromes, accounts for highest morbidity and mortality worldwide. In this study, we examined possible protective effect of coenzyme Q10 on lipid profile, atherogenic index, and liver enzyme markers in alloxan-induced type 1 diabetic rats. METHODS A total of 30 male rats were randomly divided into three groups; group 1 as control, group 2 diabetic untreatment, and group 3 treatments with coenzyme Q10 by 15 mg/kg i.p. daily, respectively .Diabetes was induced in the second and third groups by alloxan injection subcutaneously. After 8 weeks, the levels of fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), very low-density lipoprotein (VLDL), high density lipoprotein (HDL), atherogenic index, atherogenic coefficient, cardiac risk ratio, and the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) of all groups were analyzed. Data were analyzed using non-parametric Mann-Whitney test (using SPSS) and P < 0.05 was considered as significant. RESULTS Coenzyme Q10 inhibited significantly the activities of ALT (11.17%), AST (19.35%) and ALP (36.67%) and decreased FBG (21.19%), TG (37.24%), TC (17.15%), LDL (30.44%), VLDL (37.24%), atherogenic index (44.24%), atherogenic coefficient (49.69%), and cardiac risk ratio (37.97%), HDL level was significantly (33.38%) increased when treated with coenzyme Q10. CONCLUSION The findings of this study suggest that coenzyme Q10 exert beneficial effects on the lipid profile, atherogenic index, and liver enzymes activity in alloxan-induced type 1 diabetic rats. PMID:25258634

  7. A significant correlation between the plasma levels of coenzyme Q10 and vitamin B-6 and a reduced risk of coronary artery disease.

    PubMed

    Lee, Bor-Jen; Yen, Chi-Hua; Hsu, Hui-Chen; Lin, Jui-Yuan; Hsia, Simon; Lin, Ping-Ting

    2012-10-01

    Coronary artery disease (CAD) is the leading cause of death worldwide. The purpose of this study was to investigate the relationship between plasma levels of coenzyme Q10 and vitamin B-6 and the risk of CAD. Patients with at least 50% stenosis of one major coronary artery identified by cardiac catheterization were assigned to the case group (n = 45). The control group (n = 89) comprised healthy individuals with normal blood biochemistry. The plasma concentrations of coenzyme Q10 and vitamin B-6 (pyridoxal 5'-phosphate) and the lipid profiles of the participants were measured. Subjects with CAD had significantly lower plasma levels of coenzyme Q10 and vitamin B-6 compared to the control group. The plasma coenzyme Q10 concentration (β = 1.06, P = .02) and the ratio of coenzyme Q10 to total cholesterol (β = .28, P = .01) were positively correlated with vitamin B-6 status. Subjects with higher coenzyme Q10 concentration (≥516.0 nmol/L) had a significantly lower risk of CAD, even after adjusting for the risk factors for CAD. Subjects with higher pyridoxal 5'-phosphate concentration (≥59.7 nmol/L) also had a significantly lower risk of CAD, but the relationship lost its statistical significance after adjusting for the risk factors of CAD. There was a significant correlation between the plasma levels of coenzyme Q10 and vitamin B-6 and a reduced risk of CAD. Further study is needed to examine the benefits of administering coenzyme Q10 in combination with vitamin B-6 to CAD patients, especially those with low coenzyme Q10 level.

  8. Effects of aeration on formation and localization of the acetyl coenzyme A synthetases of Saccharomyces cerevisiae

    NASA Technical Reports Server (NTRS)

    Klein, H. P.; Jahnke, L.

    1979-01-01

    Previous studies on the yeast Saccharomyces cerevisiae have shown that two different forms of the enzyme acetyl coenzyme A synthetase (ACS) are present, depending on the conditions under which the cells are grown. The paper evaluates the usefulness of a method designed to assay both synthetases simultaneously in yeast homogenates. The data presented confirm the possibility of simultaneous detection and estimation of the amount of both ACSs of S. cerevisiae in crude homogenates of this strain, making possible the study of physiological factors involved in the formation of these isoenzymes. One important factor for specifying which of the two enzymes is found in these yeast cells is the presence or absence of oxygen in their environment. Aeration not only affects the ratio of the two ACSs but also appears to affect the cellular distribution of these enzymes. Most of the data presented suggest the possibility that the nonaerobic ACS may serve as a precursor to the aerobic form.

  9. Coenzyme A Binding to the Aminoglycoside Acetyltransferase (3)-IIIb Increases Conformational Sampling of Antibiotic Binding Site

    SciTech Connect

    Hu, Xiaohu; Norris, Adrianne; Baudry, Jerome Y; Serpersu, Engin H

    2011-01-01

    NMR spectroscopy experiments and molecular dynamics simulations were performed to describe the dynamic properties of the aminoglycoside acetyltransferase (3)-IIIb (AAC) in its apo and coenzyme A (CoASH) bound forms. The {sup 15}N-{sup 1}H HSQC spectra indicate a partial structural change and coupling of the CoASH binding site with another region in the protein upon the CoASH titration into the apo enzyme. Molecular dynamics simulations indicate a significant structural and dynamic variation of the long loop in the antibiotic binding domain in the form of a relatively slow (250 ns), concerted opening motion in the CoASH enzyme complex and that binding of the CoASH increases the structural flexibility of the loop, leading to an interchange between several similar equally populated conformations.

  10. Factors affecting the palmitoyl-coenzyme A desaturase of Saccharomyces cerevisiae

    NASA Technical Reports Server (NTRS)

    Klein, H. P.; Volkmann, C. M.

    1975-01-01

    The activity and stability of the palmitoyl-coenzyme A (CoA) desaturase complex of Saccharomyces cerevisiae was influenced by several factors. Cells, grown nonaerobically and then incubated with glucose, either in air or under N2, showed a marked increase in desaturase activity. Cycloheximide, added during such incubations, prevented the increase in activity, suggesting de novo synthesis. The stability of the desaturase from cells grown nonaerobically was affected by subsequent treatment of the cells; enzyme from freshly harvested cells, or from cells that were then shaken under nitrogen, readily lost activity upon washing or during density gradient analysis, whereas aerated cells, in the presence or absence of glucose, yielded stable enzyme preparations. The loss of activity in nonaerobic preparations could be reversed by adding soluble supernatant from these homogenates and could be prevented by growing the cells in the presence of palmitoleic acid and ergosterol, but not with several other lipids tested.

  11. L-carnitine enhances excretion of propionyl coenzyme A as propionylcarnitine in propionic acidemia.

    PubMed Central

    Roe, C R; Millington, D S; Maltby, D A; Bohan, T P; Hoppel, C L

    1984-01-01

    Treatment with L-carnitine greatly enhanced the formation and excretion of short-chain acylcarnitines in three patients with propionic acidemia and in three normal controls. The use of fast atom bombardment mass spectrometry and linked scanning at constant magnetic (B) to electric (E) field ratio identified the acylcarnitine as propionylcarnitine in patients with propionic acidemia. The normal children excreted mostly acetylcarnitine. Propionic acidemia and other organic acidurias are characterized by the intramitochondrial accumulation of short-chain acyl-Coenzyme A (CoA) compounds. The substrate specificity of the carnitine acetyltransferase enzyme and its steady state nature appears to facilitate elimination of propionyl groups while restoring the acyl-CoA:free CoA ratio in the mitochondrion. We suggest that L-carnitine may be a useful therapeutic approach for elimination of toxic acyl CoA compounds in several of these disorders. PMID:6725560

  12. Experimental schistosomal hepatitis: protective effect of coenzyme-Q10 against the state of oxidative stress.

    PubMed

    Othman, Ahmad A; Shoheib, Zeinab S; Abdel-Aleem, Ghada A; Shareef, Mohamed M

    2008-10-01

    Schistosoma mansoni (S. mansoni) eggs trapped in the host liver elicit a chain of oxidative processes that may be, at least in part, responsible for the pathology and progression of fibrosis associated with schistosomal hepatitis. This study was designed to assess the protective effect of the antioxidant coenzyme-Q10 (Co-Q10) against experimental S. mansoni-induced oxidative stress in the liver, and its potential role as an adjuvant to praziquantel (PZQ) therapy. The oxidative stress and overall liver function were improved under Co-Q10 therapy as evidenced by significant reduction in oxidative stress markers and preservation of antioxidant factors. Liver fibrosis was also reduced with a positive impact on liver function. Moreover, addition of Co-Q10 to PZQ therapy caused: significant reduction of liver egg load, significant improvement of the redox status, and lastly decreased liver fibrosis.

  13. Secondary coenzyme Q10 deficiencies in oxidative phosphorylation (OXPHOS) and non-OXPHOS disorders.

    PubMed

    Yubero, Delia; Montero, Raquel; Martín, Miguel A; Montoya, Julio; Ribes, Antonia; Grazina, Manuela; Trevisson, Eva; Rodriguez-Aguilera, Juan Carlos; Hargreaves, Iain P; Salviati, Leonardo; Navas, Plácido; Artuch, Rafael; Jou, Cristina; Jimenez-Mallebrera, Cecilia; Nascimento, Andres; Pérez-Dueñas, Belén; Ortez, Carlos; Ramos, Federico; Colomer, Jaume; O'Callaghan, Mar; Pineda, Mercè; García-Cazorla, Angels; Espinós, Carmina; Ruiz, Angels; Macaya, Alfons; Marcé-Grau, Anna; Garcia-Villoria, Judit; Arias, Angela; Emperador, Sonia; Ruiz-Pesini, Eduardo; Lopez-Gallardo, Ester; Neergheen, Viruna; Simões, Marta; Diogo, Luisa; Blázquez, Alberto; González-Quintana, Adrián; Delmiro, Aitor; Domínguez-González, Cristina; Arenas, Joaquín; García-Silva, M Teresa; Martín, Elena; Quijada, Pilar; Hernández-Laín, Aurelio; Morán, María; Rivas Infante, Eloy; Ávila Polo, Rainiero; Paradas Lópe, Carmen; Bautista Lorite, Juan; Martínez Fernández, Eva M; Cortés, Ana B; Sánchez-Cuesta, Ana; Cascajo, Maria V; Alcázar, María; Brea-Calvo, Gloria

    2016-09-01

    We evaluated the coenzyme Q₁₀ (CoQ) levels in patients who were diagnosed with mitochondrial oxidative phosphorylation (OXPHOS) and non-OXPHOS disorders (n=72). Data from the 72 cases in this study revealed that 44.4% of patients showed low CoQ concentrations in either their skeletal muscle or skin fibroblasts. Our findings suggest that secondary CoQ deficiency is a common finding in OXPHOS and non-OXPHOS disorders. We hypothesize that cases of CoQ deficiency associated with OXPHOS defects could be an adaptive mechanism to maintain a balanced OXPHOS, although the mechanisms explaining these deficiencies and the pathophysiological role of secondary CoQ deficiency deserves further investigation.

  14. Coenzyme A corrects pathological defects in human neurons of PANK2-associated neurodegeneration.

    PubMed

    Orellana, Daniel I; Santambrogio, Paolo; Rubio, Alicia; Yekhlef, Latefa; Cancellieri, Cinzia; Dusi, Sabrina; Giannelli, Serena G; Venco, Paola; Mazzara, Pietro G; Cozzi, Anna; Ferrari, Maurizio; Garavaglia, Barbara; Taverna, Stefano; Tiranti, Valeria; Broccoli, Vania; Levi, Sonia

    2016-10-01

    Pantothenate kinase-associated neurodegeneration (PKAN) is an early onset and severely disabling neurodegenerative disease for which no therapy is available. PKAN is caused by mutations in PANK2, which encodes for the mitochondrial enzyme pantothenate kinase 2. Its function is to catalyze the first limiting step of Coenzyme A (CoA) biosynthesis. We generated induced pluripotent stem cells from PKAN patients and showed that their derived neurons exhibited premature death, increased ROS production, mitochondrial dysfunctions-including impairment of mitochondrial iron-dependent biosynthesis-and major membrane excitability defects. CoA supplementation prevented neuronal death and ROS formation by restoring mitochondrial and neuronal functionality. Our findings provide direct evidence that PANK2 malfunctioning is responsible for abnormal phenotypes in human neuronal cells and indicate CoA treatment as a possible therapeutic intervention.

  15. The radical mechanism of biological methane synthesis by methyl-coenzyme M reductase.

    PubMed

    Wongnate, Thanyaporn; Sliwa, Dariusz; Ginovska, Bojana; Smith, Dayle; Wolf, Matthew W; Lehnert, Nicolai; Raugei, Simone; Ragsdale, Stephen W

    2016-05-20

    Methyl-coenzyme M reductase, the rate-limiting enzyme in methanogenesis and anaerobic methane oxidation, is responsible for the biological production of more than 1 billion tons of methane per year. The mechanism of methane synthesis is thought to involve either methyl-nickel(III) or methyl radical/Ni(II)-thiolate intermediates. We employed transient kinetic, spectroscopic, and computational approaches to study the reaction between the active Ni(I) enzyme and substrates. Consistent with the methyl radical-based mechanism, there was no evidence for a methyl-Ni(III) species; furthermore, magnetic circular dichroism spectroscopy identified the Ni(II)-thiolate intermediate. Temperature-dependent transient kinetics also closely matched density functional theory predictions of the methyl radical mechanism. Identifying the key intermediate in methanogenesis provides fundamental insights to develop better catalysts for producing and activating an important fuel and potent greenhouse gas.

  16. Maternal 3-methylcrotonyl-coenzyme A carboxylase deficiency with elevated 3-hydroxyisovalerylcarnitine in breast milk

    PubMed Central

    Cho, Kyung Lae; Kim, Yeo Jin; Yang, Song Hyun; Kim, Gu-Hwan

    2016-01-01

    We report here a case of maternal 3-methylcrotonyl-coenzyme A carboxylase (3-MCC) deficiency in a Korean woman. Her 2 infants had elevated 3-hydroxyisovalerylcarnitine (C5-OH) on a neonatal screening test by liquid chromatography-tandem mass spectrometry (LC-MS/MS), but normal results were found on urine organic acid analysis. The patient was subjected to serial testing and we confirmed a maternal 3-MCC deficiency by blood spot and breast milk spot test by LC-MS/MS, serum amino acid analysis, urine organic acid and molecular genetic analysis that found c.838G>T (p.Asp280Tyr) homozygous mutation within exon 9 of the MCCB gene. Especially, we confirmed marked higher levels of C5-OH on breast milk spot by LC-MS/MS, in the case of maternal 3-MCC deficiency vs. controls. PMID:28018443

  17. Isolation and characterization of cDNAs encoding wheat 3-hydroxy-3-methylglutaryl coenzyme A reductase.

    PubMed Central

    Aoyagi, K; Beyou, A; Moon, K; Fang, L; Ulrich, T

    1993-01-01

    The enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR, EC 1.1.1.34) is a key enzyme in the isoprenoid biosynthetic pathway. We have isolated partial cDNAs from wheat (Triticum aestivum) using the polymerase chain reaction. Comparison of deduced amino acid sequences of these cDNAs shows that they represent a small family of genes that share a high degree of sequence homology among themselves as well as among genes from other organisms including tomato, Arabidopsis, hamster, human, Drosophila, and yeast. Southern blot analysis reveals the presence of at least four genes. Our results concerning the tissue-specific expression as well as developmental regulation of these HMGR cDNAs highlight the important role of this enzyme in the growth and development of wheat. PMID:8108513

  18. Localization of Methyl-Coenzyme M reductase as metabolic marker for diverse methanogenic Archaea.

    PubMed

    Wrede, Christoph; Walbaum, Ulrike; Ducki, Andrea; Heieren, Iris; Hoppert, Michael

    2013-01-01

    Methyl-Coenzyme M reductase (MCR) as key enzyme for methanogenesis as well as for anaerobic oxidation of methane represents an important metabolic marker for both processes in microbial biofilms. Here, the potential of MCR-specific polyclonal antibodies as metabolic marker in various methanogenic Archaea is shown. For standard growth conditions in laboratory culture, the cytoplasmic localization of the enzyme in Methanothermobacter marburgensis, Methanothermobacter wolfei, Methanococcus maripaludis, Methanosarcina mazei, and in anaerobically methane-oxidizing biofilms is demonstrated. Under growth limiting conditions on nickel-depleted media, at low linear growth of cultures, a fraction of 50-70% of the enzyme was localized close to the cytoplasmic membrane, which implies "facultative" membrane association of the enzyme. This feature may be also useful for assessment of growth-limiting conditions in microbial biofilms.

  19. [Coenzyme Q10--its importance, properties and use in nutrition and cosmetics].

    PubMed

    Hojerová, J

    2000-05-01

    Coenzyme Q10, or ubiquinone, is a nutrient--a vitamin-like substance which plays a crucial role in the generation of cellular energy an in free radical scavenging in the human body. After the age of 35 to 40, the organism begins to lose its ability to synthesize Co Q10 from food and its deficiency develops. Ageing, poor eating habits, stress and infection--they all affect our ability to provide adequate amounts of Co Q10. Therefore Co Q10 supplementation may be very helpful for the organism. The present summarizing study reports the history of the discovery and research, properties, biochemical effects, dosage of Co Q10 deficiency in the human body. A possible use of Co Q10 as a dietary supplement and an ingredient for topical cosmetic products is described.

  20. Coenzyme Q(10): a novel therapeutic approach for Fibromyalgia? case series with 5 patients.

    PubMed

    Cordero, Mario D; Alcocer-Gómez, Elísabet; de Miguel, Manuel; Cano-García, Francisco Javier; Luque, Carlos M; Fernández-Riejo, Patricia; Fernández, Ana María Moreno; Sánchez-Alcazar, José Antonio

    2011-07-01

    Coenzyme Q(10) (CoQ(10)) is an essential electron carrier in the mitochondrial respiratory chain and a strong antioxidant. Low CoQ(10) levels have been detected in patients with Fibromyalgia (FM). The purpose of the present work was to assess the effect of CoQ(10) on symptoms of five patients with FM. Patients were evaluated clinically with Visual Analogical Scale of pain (VAS), and Fibromyalgia Impact Questionnaire (FIQ). Patients with CoQ(10) deficiency showed a statistically significant reduction on symptoms after CoQ(10) treatment during 9 months (300 mg/day). Determination of deficiency and consequent supplementation in FM may result in clinical improvement. Further analysis involving more scientifically rigorous methodology will be required to confirm this observation.

  1. Coenzyme Q releases the inhibitory effect of free fatty acids on mitochondrial glycerophosphate dehydrogenase.

    PubMed

    Rauchová, Hana; Drahota, Zdenek; Rauch, Pavel; Fato, Romana; Lenaz, Giorgio

    2003-01-01

    Data presented in this paper show that the size of the endogenous coenzyme Q (CoQ) pool is not a limiting factor in the activation of mitochondrial glycerophosphate-dependent respiration by exogenous CoQ(3), since successive additions of succinate and NADH to brown adipose tissue mitochondria further increase the rate of oxygen uptake. Because the inhibition of glycerophosphate-dependent respiration by oleate was eliminated by added CoQ(3), our data indicate that the activating effect of CoQ(3) is related to the release of the inhibitory effect of endogenous free fatty acids (FFA). Both the inhibitory effect of FFA and the activating effect of CoQ(3) could be demonstrated only for glycerophosphate-dependent respiration, while succinate- or NADH-dependent respiration was not affected. The presented data suggest differences between mitochondrial glycerophosphate dehydrogenase and succinate or NADH dehydrogenases in the transfer of reducing equivalents to the CoQ pool.

  2. The radical mechanism of biological methane synthesis by methyl-coenzyme M reductase

    SciTech Connect

    Wongnate, T.; Sliwa, D.; Ginovska, B.; Smith, D.; Wolf, M. W.; Lehnert, N.; Raugei, S.; Ragsdale, S. W.

    2016-05-19

    Methyl-coenzyme M reductase (MCR), the rate-limiting enzyme in methanogenesis and anaerobic methane oxidation, is responsible for the production of over one billion tons of methane per year. The mechanism of methane synthesis is unknown, with the two leading proposals involving either a methyl-nickel(III) (Mechanism I) or methyl radical/Ni(II)-thiolate (Mechanism II) intermediate(s). When the reaction between the active Ni(I) enzyme with substrates was studied by transient kinetic, spectroscopic and computational methods, formation of an EPR-silent Ni(II)-thiolate intermediate was positively identified by magnetic circular dichroism spectroscopy. There was no evidence for an EPR-active methyl-Ni(III) species. Temperature-dependent transient kinetic studies revealed that the activation energy for the initial catalytic step closely matched the value computed by density functional theory for Mechanism II. Thus, our results demonstrate that biological methane synthesis occurs by generation of a methyl radical.

  3. beta-hydroxyisobutyryl coenzyme A deacylase deficiency: a defect in valine metabolism associated with physical malformations

    SciTech Connect

    Brown, G.K.; Hunt, S.M.; Scholem, R.; Fowler, K.; Grimes, A.; Mercer, J.F.; Truscott, R.M.; Cotton, R.G.; Rogers, J.G.; Danks, D.M.

    1982-10-01

    An infant, born to parents who were first cousins had multiple physical malformations. An associated biochemical abnormality was suggested by the urinary excretion of cysteine and cysteamine conjugates of methacrylic acid. The coenzyme A (CoA) ester of this compound is an intermediate in the pathway of valine oxidation. Subsequent investigation revealed a deficiency of beta-hydroxyisobutyryl-CoA deacylase, an enzyme unique to valine metabolism. The enzyme defect results in accumulation of methacrylyl-CoA, a highly reactive compound, which readily undergoes addition reactions with free sulfhydryl groups. Tissue damage due to reactions between methacrylyl-CoA and important sulfhydryl-containing enzymes and cofactors may account for the teratogenic effects seen in this patient.

  4. Metabolic syndrome: adenosine monophosphate-activated protein kinase and malonyl coenzyme A.

    PubMed

    Ruderman, Neil B; Saha, Asish K

    2006-02-01

    The metabolic syndrome can be defined as a state of metabolic dysregulation characterized by insulin resistance, central obesity, and a predisposition to type 2 diabetes, dyslipidemia, premature atherosclerosis, and other diseases. An increasing body of evidence has linked the metabolic syndrome to abnormalities in lipid metabolism that ultimately lead to cellular dysfunction. We review here the hypothesis that, in many instances, the cause of these lipid abnormalities could be a dysregulation of the adenosine monophosphate-activated protein kinase (AMPK)/malonyl coenzyme A (CoA) fuel-sensing and signaling mechanism. Such dysregulation could be reflected by isolated increases in malonyl CoA or by concurrent changes in malonyl CoA and AMPK, both of which would alter intracellular fatty acid partitioning. The possibility is also raised that pharmacological agents and other factors that activate AMPK and/or decrease malonyl CoA could be therapeutic targets.

  5. Purification and properties of 4-hydroxybutyrate coenzyme A transferase from Clostridium aminobutyricum.

    PubMed Central

    Scherf, U; Buckel, W

    1991-01-01

    A new coenzyme A (CoA)-transferase from the anaerobe Clostridium aminobutyricum catalyzing the formation of 4-hydroxybutyryl-CoA from 4-hydroxybutyrate and acetyl-CoA is described. The enzyme was purified to homogeneity by standard techniques, including fast protein liquid chromatography under aerobic conditions. Its molecular mass was determined to be 110 kDa, and that of the only subunit was determined to be 54 kDa, indicating a homodimeric structure. Besides acetate and acetyl-CoA, the following substrates were detected (in order of decreasing kcat/Km): 4-hydroxybutyryl-CoA, butyryl-CoA and propionyl-CoA, vinyl-acetyl-CoA (3-butenoyl-CoA), and 5-hydroxyvaleryl-CoA. In an indirect assay the corresponding acids were also found to be substrates; however, DL-lactate, DL-2-hydroxybutyrate, DL-3-hydroxybutyrate, crotonate, and various dicarboxylates were not. PMID:1768145

  6. Sensitive non-radioactive determination of aminotransferase stereospecificity for C-4' hydrogen transfer on the coenzyme.

    PubMed

    Jomrit, Juntratip; Summpunn, Pijug; Meevootisom, Vithaya; Wiyakrutta, Suthep

    2011-02-25

    A sensitive non-radioactive method for determination of the stereospecificity of the C-4' hydrogen transfer on the coenzymes (pyridoxal phosphate, PLP; and pyridoxamine phosphate, PMP) of aminotransferases has been developed. Aminotransferase of unknown stereospecificity in its PLP form was incubated in (2)H(2)O with a substrate amino acid resulted in PMP labeled with deuterium at C-4' in the pro-S or pro-R configuration according to the stereospecificity of the aminotransferase tested. The [4'-(2)H]PMP was isolated from the enzyme protein and divided into two portions. The first portion was incubated in aqueous buffer with apo-aspartate aminotransferase (a reference si-face specific enzyme), and the other was incubated with apo-branched-chain amino acid aminotransferase (a reference re-face specific enzyme) in the presence of a substrate 2-oxo acid. The (2)H at C-4' is retained with the PLP if the aminotransferase in question transfers C-4' hydrogen on the opposite face of the coenzyme compared with the reference aminotransferase, but the (2)H is removed if the test and reference aminotransferases catalyze hydrogen transfer on the same face. PLP formed in the final reactions was analyzed by LC-MS/MS for the presence or absence of (2)H. The method was highly sensitive that for the aminotransferase with ca. 50 kDa subunit molecular weight, only 2mg of the enzyme was sufficient for the whole test. With this method, the use of radioactive substances could be avoided without compromising the sensitivity of the assay.

  7. TD-DFT Insight into Photodissociation of Co-C Bond in Coenzyme B12

    NASA Astrophysics Data System (ADS)

    Kozlowski, Pawel; Liu, Hui; Kornobis, Karina; Lodowski, Piotr; Jaworska, Maria

    2013-12-01

    Coenzyme B12 (AdoCbl) is one of the most biologically active forms of vitamin B12, and continues to be a topic of active research interest. The mechanism of Co-C bond cleavage in AdoCbl, and the corresponding enzymatic reactions are however, not well understood at the molecular level. In this work, time-dependent density functional theory (TD-DFT) has been applied to investigate the photodissociation of coenzyme B12. To reduce computational cost, while retaining the major spectroscopic features of AdoCbl, a truncated model based on ribosylcobalamin (RibCbl) was used to simulate Co-C photodissociation. Equilibrium geometries of RibCbl were obtained by optimization at the DFT/BP86/TZVP level of theory, and low-lying excited states were calculated by TD-DFT using the same functional and basis set. The calculated singlet states, and absorption spectra were simulated in both the gas phase, and water, using the polarizable continuum model (PCM). Both spectra were in reasonable agreement with experimental data, and potential energy curves based on vertical excitations were plotted to explore the nature of Co-C bond dissociation. It was found that a repulsive 3(σCo-C → σ*Co-C) triplet state became dissociative at large Co-C bond distance, similar to a previous observation for methylcobalamin (MeCbl). Furthermore, potential energy surfaces (PESs) obtained as a function of both Co-CRib and Co-NIm distances, identify the S1 state as a key intermediate generated during photoexcitation of RibCbl, attributed to a mixture of a MLCT (metal-to-ligand charge transfer) and a σ bonding-ligand charge transfer (SBLCT) states.

  8. Unexpected abundance of coenzyme F(420)-dependent enzymes in Mycobacterium tuberculosis and other actinobacteria.

    PubMed

    Selengut, Jeremy D; Haft, Daniel H

    2010-11-01

    Regimens targeting Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), require long courses of treatment and a combination of three or more drugs. An increase in drug-resistant strains of M. tuberculosis demonstrates the need for additional TB-specific drugs. A notable feature of M. tuberculosis is coenzyme F(420), which is distributed sporadically and sparsely among prokaryotes. This distribution allows for comparative genomics-based investigations. Phylogenetic profiling (comparison of differential gene content) based on F(420) biosynthesis nominated many actinobacterial proteins as candidate F(420)-dependent enzymes. Three such families dominated the results: the luciferase-like monooxygenase (LLM), pyridoxamine 5'-phosphate oxidase (PPOX), and deazaflavin-dependent nitroreductase (DDN) families. The DDN family was determined to be limited to F(420)-producing species. The LLM and PPOX families were observed in F(420)-producing species as well as species lacking F(420) but were particularly numerous in many actinobacterial species, including M. tuberculosis. Partitioning the LLM and PPOX families based on an organism's ability to make F(420) allowed the application of the SIMBAL (sites inferred by metabolic background assertion labeling) profiling method to identify F(420)-correlated subsequences. These regions were found to correspond to flavonoid cofactor binding sites. Significantly, these results showed that M. tuberculosis carries at least 28 separate F(420)-dependent enzymes, most of unknown function, and a paucity of flavin mononucleotide (FMN)-dependent proteins in these families. While prevalent in mycobacteria, markers of F(420) biosynthesis appeared to be absent from the normal human gut flora. These findings suggest that M. tuberculosis relies heavily on coenzyme F(420) for its redox reactions. This dependence and the cofactor's rarity may make F(420)-related proteins promising drug targets.

  9. Structure of Coenzyme A-Disulfide Reductase from Staphylococcus aureus at 1.54 Angstrom Resolution

    SciTech Connect

    Mallett,T.; Wallen, J.; Karplus, P.; Sakai, H.; Tsukihara, T.; Claiborne, A.

    2006-01-01

    Coenzyme A (CoASH) replaces glutathione as the major low molecular weight thiol in Staphylococcus aureus; it is maintained in the reduced state by coenzyme A-disulfide reductase (CoADR), a homodimeric enzyme similar to NADH peroxidase but containing a novel Cys43-SSCoA redox center. The crystal structure of S. aureus CoADR has been solved using multiwavelength anomalous dispersion data and refined at a resolution of 1.54 {angstrom}. The resulting electron density maps define the Cys43-SSCoA disulfide conformation, with Cys43-S{gamma} located at the flavin si face, 3.2 {angstrom} from FAD-C4aF, and the CoAS- moiety lying in an extended conformation within a cleft at the dimer interface. A well-ordered chloride ion is positioned adjacent to the Cys43-SSCoA disulfide and receives a hydrogen bond from Tyr361'-OH of the complementary subunit, suggesting a role for Tyr361' as an acid-base catalyst during the reduction of CoAS-disulfide. Tyr419'-OH is located 3.2 {angstrom} from Tyr361'-OH as well and, based on its conservation in known functional CoADRs, also appears to be important for activity. Identification of residues involved in recognition of the CoAS-disulfide substrate and in formation and stabilization of the Cys43-SSCoA redox center has allowed development of a CoAS-binding motif. Bioinformatics analyses indicate that CoADR enzymes are broadly distributed in both bacterial and archaeal kingdoms, suggesting an even broader significance for the CoASH/CoAS-disulfide redox system in prokaryotic thiol/disulfide homeostasis.

  10. Smoking habits and coenzyme Q10 status in healthy European adults

    PubMed Central

    Fischer, Alexandra; Onur, Simone; Paulussen, Michael; Menke, Thomas; Döring, Frank

    2016-01-01

    Introduction Coenzyme Q10 (CoQ10) is a lipophilic endogenously synthesised antioxidant that is present in nearly all human tissues and plays an important role in mitochondrial energy production. It has been postulated that smoking has a consumptive effect on CoQ10. Material and methods To further define the relation between smoking and the serum CoQ10 status, 276 healthy volunteers aged 19 to 62 years were grouped into non-smokers (n = 113; 77 male, 36 female) and smokers (n = 163; 102 male, 61 female). Serum lipid profile was analysed by standard clinical chemistry. Coenzyme Q10 concentration and redox status were analysed by high-pressure liquid chromatography with electrochemical detection. Results Male smokers showed higher serum CoQ10 levels than female smokers. This sex-related difference was accounted for when CoQ10 was related to low-density lipoprotein (LDL) cholesterol as the main carrier of CoQ10 in the circulation. Neither LDL-adjusted CoQ10 concentration nor redox status significantly differed when smokers and non-smokers were compared. Regarding the smoking history, the number of cigarettes consumed per day did not significantly affect the CoQ10 status. Interestingly, with increasing time of smoking habit we observed increasing levels of LDL-adjusted serum CoQ10 concentration (Spearman's p < 0.002) and of the reduced form of CoQ10 (Spearman's p < 0.0001). Conclusions As an adaptive response to oxidative stress in long-term smokers an increased demand for antioxidant capacity may be covered by increasing levels of LDL-adjusted CoQ10 serum concentrations and by a concomitantly increased availability of the reduced, active form of CoQ10, possibly by induction of enzymes that are involved in converting CoQ10ox to CoQ10red. PMID:27478450

  11. The reaction mechanism of methyl-coenzyme M reductase: How an enzyme enforces strict binding order

    DOE PAGES

    Wongnate, Thanyaporn; Ragsdale, Stephen W.

    2015-02-17

    Methyl-coenzyme M reductase (MCR) is a nickel tetrahydrocorphinoid (coenzyme F430) containing enzyme involved in the biological synthesis and anaerobic oxidation of methane. MCR catalyzes the conversion of methyl-2-mercaptoethanesulfonate (methyl-SCoM) and N-7-mercaptoheptanoylthreonine phosphate (CoB7SH) to CH4 and the mixed disulfide CoBS-SCoM. In this study, the reaction of MCR from Methanothermobacter marburgensis, with its native substrates was investigated using static binding, chemical quench, and stopped-flow techniques. Rate constants were measured for each step in this strictly ordered ternary complex catalytic mechanism. Surprisingly, in the absence of the other substrate, MCR can bind either substrate; however, only one binary complex (MCR·methyl-SCoM) is productivemore » whereas the other (MCR·CoB7SH) is inhibitory. Moreover, the kinetic data demonstrate that binding of methyl-SCoM to the inhibitory MCR·CoB7SH complex is highly disfavored (Kd = 56 mM). However, binding of CoB7SH to the productive MCR·methyl-SCoM complex to form the active ternary complex (CoB7SH·MCR(NiI)·CH3SCoM) is highly favored (Kd = 79 μM). Only then can the chemical reaction occur (kobs = 20 s-1 at 25 °C), leading to rapid formation and dissociation of CH4 leaving the binary product complex (MCR(NiII)·CoB7S-·SCoM), which undergoes electron transfer to regenerate Ni(I) and the final product CoBS-SCoM. In conclusion, this first rapid kinetics study of MCR with its natural substrates describes how an enzyme can enforce a strictly ordered ternary complex mechanism and serves as a template for identification of the reaction intermediates.« less

  12. Coenzyme Q10 protects against acute consequences of experimental myocardial infarction in rats

    PubMed Central

    Eleawa, Samy M; Alkhateeb, Mahmoud; Ghosh, Sanjoy; Al-Hashem, Fahaid; Shatoor, Abdullah S; Alhejaily, Abdulmohsen; Khalil, Mohammad A

    2015-01-01

    Aim: Myocardial infarction (MI) due to sudden occlusion of a major coronary artery leads to a complex series of events that result in left ventricle (LV) impairment eventual heart failure. Therapeutic options are limited to reverse such trends post MI. The aim of this study was to compare the acute cardioprotective effects of the antioxidants, resveratrol (RES) and coenzyme Q10 (CoQ10), either individually or in combination, on infracts size, LV hemodynamics, inflammation and oxidative stress markers in rats with experimentally induced MI. Methods: Male Wistar rats were randomly divided into six groups: control without surgery, sham without occlusion, MI without antioxidants, RES pre-treated then MI (20 mg/kg, orally), CoQ10 then MI (20 mg/kg, intramuscular.), and combined RES and CoQ10 then MI with (each group n = 10). Pretreatment commenced 7 days prior to the permanent occlusion of the left anterior descending (LAD) coronary artery. Infarct area, hemodynamics, inflammation and oxidative stress markers were assessed 24 hours post-MI. Results: Compared to RES alone, CoQ10 pre-administration either by itself or in combination with RES, significantly reduced LV infarct area (57%), and normalized LV hemodynamic parameters like LVEDP (100%), LVSP (95.4%), LV +dp/dt and -dp/dt (102 and 73.1%, respectively). CoQ10 also decreased serum levels of brain natriuretic peptide (70%), and various circulating inflammatory markers like TNF-α (83.2%) and IL-6 (83.2%). Regarding oxidative stress, TBARS scores were lowered with a concurrent increase in both superoxide dismutase and glutathione peroxidase activities with CoQ10 alone or in combination with RES. Conclusion: Coenzyme Q10 protects against the acute sequelae of myocardial infarction. It profoundly reduced infarct area, inflammation and oxidative stress while normalizing LV hemodynamics post MI. PMID:26069524

  13. The reaction mechanism of methyl-coenzyme M reductase: how an enzyme enforces strict binding order.

    PubMed

    Wongnate, Thanyaporn; Ragsdale, Stephen W

    2015-04-10

    Methyl-coenzyme M reductase (MCR) is a nickel tetrahydrocorphinoid (coenzyme F430) containing enzyme involved in the biological synthesis and anaerobic oxidation of methane. MCR catalyzes the conversion of methyl-2-mercaptoethanesulfonate (methyl-SCoM) and N-7-mercaptoheptanoylthreonine phosphate (CoB7SH) to CH4 and the mixed disulfide CoBS-SCoM. In this study, the reaction of MCR from Methanothermobacter marburgensis, with its native substrates was investigated using static binding, chemical quench, and stopped-flow techniques. Rate constants were measured for each step in this strictly ordered ternary complex catalytic mechanism. Surprisingly, in the absence of the other substrate, MCR can bind either substrate; however, only one binary complex (MCR·methyl-SCoM) is productive whereas the other (MCR·CoB7SH) is inhibitory. Moreover, the kinetic data demonstrate that binding of methyl-SCoM to the inhibitory MCR·CoB7SH complex is highly disfavored (Kd = 56 mM). However, binding of CoB7SH to the productive MCR·methyl-SCoM complex to form the active ternary complex (CoB7SH·MCR(Ni(I))·CH3SCoM) is highly favored (Kd = 79 μM). Only then can the chemical reaction occur (kobs = 20 s(-1) at 25 °C), leading to rapid formation and dissociation of CH4 leaving the binary product complex (MCR(Ni(II))·CoB7S(-)·SCoM), which undergoes electron transfer to regenerate Ni(I) and the final product CoBS-SCoM. This first rapid kinetics study of MCR with its natural substrates describes how an enzyme can enforce a strictly ordered ternary complex mechanism and serves as a template for identification of the reaction intermediates.

  14. A Randomized Trial of Coenzyme Q10 in Patients with Statin Myopathy: Rationale and Study Design

    PubMed Central

    Parker, Beth A.; Gregory, Sara M.; Lorson, Lindsay; Polk, Donna; White, C. Michael; Thompson, Paul D.

    2013-01-01

    Background Statins are the most commonly prescribed and effective medications for reducing low-density lipoprotein levels. Some patients experience myopathic symptoms during statin treatment. The etiology is not known, but depletion of mevalonate pathway metabolites, including coenzyme Q10 (CoQ10), has been suggested. CoQ10 supplementation has been recommended to patients who experience myalgic symptoms despite a lack of conclusive evidence supporting its utility. Objective The Co-Enzyme Q10 in Statin Myopathy study is designed to examine the effect of CoQ10 supplementation on the extent and intensity of muscle pain during treatment with simvastatin. Methods We will recruit patients with a documented history of myalgia during statin treatment. The presence of statin-related myalgia will be confirmed in a crossover run-in trial during which presence and absence of symptoms will be documented during statin and placebo treatment, respectively. Individuals with myalgic symptoms while on statin but not placebo will be randomized to receive simvastatin 20 mg daily plus either 600 mg daily of CoQ10 or placebo. Muscle pain intensity will be documented during weekly phone calls using the Brief Pain Inventory (Short Form) (BPI-SF). Treatment will continue for 8 weeks or until muscle symptoms are reported continuously for one week or become intolerable, and then subjects will crossover to the alternative treatment (CoQ10 or placebo). Results This study is an ongoing clinical trial. Conclusions This study will determine the utility of CoQ10 for reducing pain intensity in myalgic patients and will provide guidance for clinicians treating patients with hypercholesterolemia who are intolerant to statins. PMID:23725917

  15. Unexpected Abundance of Coenzyme F420-Dependent Enzymes in Mycobacterium tuberculosis and Other Actinobacteria▿ †

    PubMed Central

    Selengut, Jeremy D.; Haft, Daniel H.

    2010-01-01

    Regimens targeting Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), require long courses of treatment and a combination of three or more drugs. An increase in drug-resistant strains of M. tuberculosis demonstrates the need for additional TB-specific drugs. A notable feature of M. tuberculosis is coenzyme F420, which is distributed sporadically and sparsely among prokaryotes. This distribution allows for comparative genomics-based investigations. Phylogenetic profiling (comparison of differential gene content) based on F420 biosynthesis nominated many actinobacterial proteins as candidate F420-dependent enzymes. Three such families dominated the results: the luciferase-like monooxygenase (LLM), pyridoxamine 5′-phosphate oxidase (PPOX), and deazaflavin-dependent nitroreductase (DDN) families. The DDN family was determined to be limited to F420-producing species. The LLM and PPOX families were observed in F420-producing species as well as species lacking F420 but were particularly numerous in many actinobacterial species, including M. tuberculosis. Partitioning the LLM and PPOX families based on an organism's ability to make F420 allowed the application of the SIMBAL (sites inferred by metabolic background assertion labeling) profiling method to identify F420-correlated subsequences. These regions were found to correspond to flavonoid cofactor binding sites. Significantly, these results showed that M. tuberculosis carries at least 28 separate F420-dependent enzymes, most of unknown function, and a paucity of flavin mononucleotide (FMN)-dependent proteins in these families. While prevalent in mycobacteria, markers of F420 biosynthesis appeared to be absent from the normal human gut flora. These findings suggest that M. tuberculosis relies heavily on coenzyme F420 for its redox reactions. This dependence and the cofactor's rarity may make F420-related proteins promising drug targets. PMID:20675471

  16. Coenzyme Q10 plus Multivitamin Treatment Prevents Cisplatin Ototoxicity in Rats

    PubMed Central

    Astolfi, Laura; Simoni, Edi; Valente, Filippo; Ghiselli, Sara; Hatzopoulos, Stavros; Chicca, Milvia; Martini, Alessandro

    2016-01-01

    Cisplatin (Cpt) is known to induce a high level of oxidative stress, resulting in an increase of reactive oxygen species damaging the inner ear and causing hearing loss at high frequencies. Studies on animal models show that antioxidants may lower Cpt-induced ototoxicity. The aim of this study is to evaluate the ototoxic effects of two different protocols of Cpt administration in a Sprague-Dawley rat model, and to test in the same model the synergic protective effects of a solution of coenzyme Q10 terclatrate and Acuval 400®, a multivitamin supplement containing antioxidant agents and minerals (Acu-Qter). The Cpt was administered intraperitoneally in a single dose (14 mg/kg) or in three daily doses (4.6 mg/kg/day) to rats orally treated or untreated with Acu-Qter for 5 days. The auditory function was assessed by measuring auditory brainstem responses from 2 to 32 kHz at day 0 and 5 days after treatment. Similar hearing threshold and body weight alterations were observed in both Cpt administration protocols, but mortality reduced to zero when Cpt was administered in three daily doses. The Acu-Qter treatment was able to prevent and completely neutralize ototoxicity in rats treated with three daily Cpt doses, supporting the synergic protective effects of coenzyme Q terclatrate and Acuval 400® against Cpt-induced oxidative stress. The administration protocol involving three Cpt doses is more similar to common human chemotherapy protocols, therefore it appears more useful for long-term preclinical studies on ototoxicity prevention. PMID:27632426

  17. Cloning and characterization of the gene encoding 1-cyclohexenylcarbonyl coenzyme A reductase from Streptomyces collinus.

    PubMed Central

    Wang, P; Denoya, C D; Morgenstern, M R; Skinner, D D; Wallace, K K; Digate, R; Patton, S; Banavali, N; Schuler, G; Speedie, M K; Reynolds, K A

    1996-01-01

    We report the cloning of the gene encoding the 1-cyclohexenylcarbonyl coenzyme A reductase (ChcA) of Streptomyces collinus, an enzyme putatively involved in the final reduction step in the formation of the cyclohexyl moiety of ansatrienin from shikimic acid. The cloned gene, with a proposed designation of chcA, encodes an 843-bp open reading frame which predicts a primary translation product of 280 amino acids and a calculated molecular mass of 29.7 kDa. Highly significant sequence similiarity extending along almost the entire length of the protein was observed with members of the short-chain alcohol dehydrogenase superfamily. The S. collinus chcA gene was overexpressed in Escherichia coli by using a bacteriophage T7 transient expression system, and a protein with a specific ChcA activity was detected. The E. coli-produced ChcA protein was purified and shown to have similar steady-state kinetics and electrophoretic mobility on sodium dodecyl sulfate-polyacrylamide gels as the enoyl-coenzyme A reductase protein prepared from S. collinus. The enzyme demonstrated the ability to catalyze, in vitro, three of the reductive steps involved in the formation of cyclohexanecarboxylic acid. An S. collinus chcA mutant, constructed by deletion of a genomic region comprising the 5' end of chcA, lost the ChcA activity and the ability to synthesize either cyclohexanecarboxylic acid or ansatrienin. These results suggest that chcA encodes the ChcA that is involved in catalyzing multiple reductive steps in the pathway that provides the cyclohexanecarboxylic acid from shikimic acid. PMID:8955309

  18. Methyl-coenzyme M reductase A as an indicator to estimate methane production from dairy cows.

    PubMed

    Aguinaga Casañas, M A; Rangkasenee, N; Krattenmacher, N; Thaller, G; Metges, C C; Kuhla, B

    2015-06-01

    The evaluation of greenhouse gas mitigation strategies requires the quantitative assessment of individual methane production. Because methane measurement in respiration chambers is highly accurate, but also comprises various disadvantages such as limited capacity and high costs, the establishment of an indicator for estimating methane production of individual ruminants would provide an alternative to direct methane measurement. Methyl-coenzyme M reductase is involved in methanogenesis and the subunit α of methyl-coenzyme M reductase is encoded by the mcrA gene of rumen archaea. We therefore examined the relationship between methane emissions of Holstein dairy cows measured in respiration chambers with 2 different diets (high- and medium-concentrate diet) and the mcrA DNA and mcrA cDNA abundance determined from corresponding rumen fluid samples. Whole-body methane production per kilogram of dry matter intake and mcrA DNA normalized to the abundance of the rrs gene coding for 16S rRNA correlated significantly when using qmcrA primers. Use of qmcrA primers also revealed linear correlation between mcrA DNA copy number and methane yield. Regression analyses based on normalized mcrA cDNA abundances revealed no significant linear correlation with methane production per kilogram of dry matter intake. Furthermore, the correlations between normalized mcrA DNA abundance and the rumen fluid concentration of acetic and isobutyric acid were positive, whereas the correlations with propionic and lactic acid were negative. These data suggest that the mcrA DNA approach based on qmcrA primers could potentially be a molecular proxy for methane yield after further refinement.

  19. Linkage of subunit interactions, structural changes, and energetics of coenzyme binding in tryptophan synthase.

    PubMed

    Wiesinger, H; Hinz, H J

    1984-10-09

    The energetics of binding of the coenzyme pyridoxal 5'-phosphate (PLP) to both the apo beta 2 subunit and the apo alpha 2 beta 2 complex of tryptophan synthase from Escherichia coli has been investigated as a function of pH and temperature by direct microcalorimetric methods. At 25 degrees C, pH 7.5, the binding process proceeds in the time range of minutes and shows a biphasic heat output which permits resolution of the overall reaction into different reaction steps. Binding studies on the coenzyme analogues pyridoxal (PAL), pyridoxine 5'-phosphate (PNP), and pyridoxine (POL) to the protein as well as a comparison of these results with data from studies on PLP binding to epsilon-aminocaproic acid have led to a deconvolution of the complex heat vs. time curves into fast endothermic contributions from electrostatic interaction and Schiff base formation and slow exothermic contributions from the interactions between PLP and the binding domain. The pH-independent, large negative change in heat capacity of about -9.1 kJ/(mol of beta 2 X K) when binding PLP to beta 2 is indicative of major structural changes resulting from complex formation. The much smaller value of delta Cp = -1.7 kJ/(mol of beta 2 X K) for binding of PLP to alpha 2 beta 2 clearly demonstrates the energetic linkage of protein-protein and protein-ligand interactions. Calorimetric titrations of the apo beta 2 subunit with PLP at 35 degrees C have shown that also at this temperature positive cooperativity between the two binding sites occurs. On the basis of these measurements a complete set of site-specific thermodynamic parameters has been established.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Effect of Simvastatin, Coenzyme Q10, Resveratrol, Acetylcysteine and Acetylcarnitine on Mitochondrial Respiration.

    PubMed

    Fišar, Z; Hroudová, J; Singh, N; Kopřivová, A; Macečková, D

    2016-01-01

    Some therapeutic and/or adverse effects of drugs may be related to their effects on mitochondrial function. The effects of simvastatin, resveratrol, coenzyme Q10, acetylcysteine, and acetylcarnitine on Complex I-, Complex II-, or Complex IV-linked respiratory rate were determined in isolated brain mitochondria. The protective effects of these biologically active compounds on the calcium-induced decrease of the respiratory rate were also studied. We observed a significant inhibitory effect of simvastatin on mitochondrial respiration (IC50 = 24.0 μM for Complex I-linked respiration, IC50 = 31.3 μM for Complex II-linked respiration, and IC50 = 42.9 μM for Complex IV-linked respiration); the inhibitory effect of resveratrol was found at very high concentrations (IC50 = 162 μM for Complex I-linked respiration, IC50 = 564 μM for Complex II-linked respiration, and IC50 = 1454 μM for Complex IV-linked respiration). Concentrations required for effective simvastatin- or resveratrol-induced inhibition of mitochondrial respiration were found much higher than concentrations achieved under standard dosing of these drugs. Acetylcysteine and acetylcarnitine did not affect the oxygen consumption rate of mitochondria. Coenzyme Q10 induced an increase of Complex I-linked respiration. The increase of free calcium ions induced partial inhibition of the Complex I+II-linked mitochondrial respiration, and all tested drugs counteracted this inhibition. None of the tested drugs showed mitochondrial toxicity (characterized by respiratory rate inhibition) at drug concentrations achieved at therapeutic drug intake. Resveratrol, simvastatin, and acetylcarnitine had the greatest neuroprotective potential (characterized by protective effects against calcium-induced reduction of the respiratory rate).

  1. Transcriptional Regulation by the Short-Chain Fatty Acyl Coenzyme A Regulator (ScfR) PccR Controls Propionyl Coenzyme A Assimilation by Rhodobacter sphaeroides

    PubMed Central

    Carter, Michael S.

    2015-01-01

    ABSTRACT Propionyl coenzyme A (propionyl-CoA) assimilation by Rhodobacter sphaeroides proceeds via the methylmalonyl-CoA pathway. The activity of the key enzyme of the pathway, propionyl-CoA carboxylase (PCC), was upregulated 20-fold during growth with propionate compared to growth with succinate. Because propionyl-CoA is an intermediate in acetyl-CoA assimilation via the ethylmalonyl-CoA pathway, acetate growth also requires the methylmalonyl-CoA pathway. PCC activities were upregulated 8-fold in extracts of acetate-grown cells compared to extracts of succinate-grown cells. The upregulation of PCC activities during growth with propionate or acetate corresponded to increased expression of the pccB gene, which encodes a subunit of PCC. PccR (RSP_2186) was identified to be a transcriptional regulator required for the upregulation of pccB transcript levels and, consequently, PCC activity: growth substrate-dependent regulation was lost when pccR was inactivated by an in-frame deletion. In the pccR mutant, lacZ expression from a 215-bp plasmid-borne pccB upstream fragment including 27 bp of the pccB coding region was also deregulated. A loss of regulation as a result of mutations in the conserved motifs TTTGCAAA-X4-TTTGCAAA in the presence of PccR allowed the prediction of a possible operator site. PccR, together with homologs from other organisms, formed a distinct clade within the family of short-chain fatty acyl coenzyme A regulators (ScfRs) defined here. Some members from other clades within the ScfR family have previously been shown to be involved in regulating acetyl-CoA assimilation by the glyoxylate bypass (RamB) or propionyl-CoA assimilation by the methylcitrate cycle (MccR). IMPORTANCE Short-chain acyl-CoAs are intermediates in essential biosynthetic and degradative pathways. The regulation of their accumulation is crucial for appropriate cellular function. This work identifies a regulator (PccR) that prevents the accumulation of propionyl-CoA by controlling

  2. Global effects of the energetics of coenzyme binding: NADPH controls the protein interaction properties of human cytochrome P450 reductase.

    PubMed

    Grunau, Alex; Paine, Mark J; Ladbury, John E; Gutierrez, Aldo

    2006-02-07

    The thermodynamics of coenzyme binding to human cytochrome P450 reductase (CPR) and its isolated FAD-binding domain have been studied by isothermal titration calorimetry. Binding of 2',5'-ADP, NADP(+), and H(4)NADP, an isosteric NADPH analogue, is described in terms of the dissociation binding constant (K(d)), the enthalpy (DeltaH(B)) and entropy (TDeltaS(B)) of binding, and the heat capacity change (DeltaC(p)). This systematic approach allowed the effect of coenzyme redox state on binding to CPR to be determined. The recognition and stability of the coenzyme-CPR complex are largely determined by interaction with the adenosine moiety (K(d2)(')(,5)(')(-ADP) = 76 nM), regardless of the redox state of the nicotinamide moiety. Similar heat capacity change (DeltaC(p)) values for 2',5'-ADP (-210 cal mol(-)(1) K(-)(1)), NADP(+) (-230 cal mol(-)(1) K(-)(1)), and H(4)NADP (-220 cal mol(-)(1) K(-)(1)) indicate no significant contribution from the nicotinamide moiety to the binding interaction surface. The coenzyme binding stoichiometry to CPR is 1:1. This result validates a recently proposed one-site kinetic model [Daff, S. (2004) Biochemistry 43, 3929-3932] as opposed to a two-site model previously suggested by us [Gutierrez, A., Lian, L.-Y., Wolf, C. R., Scrutton, N. S., and Roberts, C. G. K. (2001) Biochemistry 40, 1964-1975]. Calorimetric studies in which binding of 2',5'-ADP to CPR (TDeltaS(B) = -13400 +/- 200 cal mol(-)(1), 35 degrees C) was compared with binding of the same ligand to the isolated FAD-binding domain (TDeltaS(B) = -11200 +/- 300 cal mol(-)(1), 35 degrees C) indicate that the number of accessible conformational substates of the protein increases upon 2',5'-ADP binding in the presence of the FMN-binding domain. This pattern was consistently observed along the temperature range that was studied (5-35 degrees C). This contribution of coenzyme binding energy to domain dynamics in CPR agrees with conclusions from previous temperature-jump studies [Gutierrez

  3. TURNOVER-DEPENDENT COVALENT INACTIVATION OF Staphylococcus aureus COENZYME A-DISULFIDE REDUCTASE BY COENZYME A-MIMETICS: MECHANISTIC AND STRUCTURAL INSIGHTS†,‡

    PubMed Central

    Wallace, Bret D.; Edwards, Jonathan S.; Wallen, Jamie R.; Moolman, Wessel J.A.; van der Westhuyzen, Renier; Strauss, Erick; Redinbo, Matthew R.; Claiborne, Al

    2012-01-01

    Disruption of the unusual thiol-based redox homeostasis mechanisms in Staphylococcus aureus represents a unique opportunity to identify new metabolic processes, and new targets for intervention. Targeting uncommon aspects of CoASH biosynthetic and redox functions in S. aureus, the antibiotic CJ-15,801 has recently been demonstrated to be an antimetabolite of the CoASH biosynthetic pathway in this organism; CoAS-mimetics containing α,β-unsaturated sulfone and carboxyl moieties have also been exploited as irreversible inhibitors of S. aureus coenzyme A-disulfide reductase (SaCoADR). In this work we have determined the crystal structures of three of these covalent SaCoADR-inhibitor complexes, prepared by inactivation of wild-type enzyme during turnover. The structures reveal the covalent linkage between the active-site Cys43-Sγ and Cβ of the vinyl sulfone or carboxyl moiety. The full occupancy of two inhibitor molecules per enzyme dimer, together with kinetic analyses of the wild-type/C43S heterodimer, indicates that half-sites-reactivity is not a factor during normal catalytic turnover. Further, we provide the structures of SaCoADR active-site mutants; in particular, Tyr419′-OH plays dramatic roles in directing intramolecular reduction of the Cys43-SSCoA redox center, in the redox asymmetry observed for the two FAD per dimer in NADPH titrations, and in catalysis. The two conformations observed for the Ser43 side chain in the C43S mutant structure lend support to a conformational switch for Cys43-Sγ during its catalytic Cys43-SSCoA/Cys43-SH redox cycle. Finally, the structures of the three inhibitor complexes provide a framework for design of more effective inhibitors with therapeutic potential against several major bacterial pathogens. PMID:22954034

  4. Determination of methylmalonyl coenzyme A by ultra high-performance liquid chromatography tandem mass spectrometry for measuring propionyl coenzyme A carboxylase activity in patients with propionic acidemia.

    PubMed

    Gotoh, Kana; Nakajima, Yoko; Tajima, Go; Watanabe, Yoriko; Hotta, Yuji; Kataoka, Tomoya; Kawade, Yoshihiro; Sugiyama, Naruji; Ito, Tetsuya; Kimura, Kazunori; Maeda, Yasuhiro

    2017-03-01

    Propionic acidemia (PA) is an inherited metabolic disease caused by low activity of propionyl coenzyme A (CoA) carboxylase (PCC), which metabolizes propionyl-CoA into methylmalonyl-CoA. Although many patients with PA have been identified by tandem mass spectrometry since the test was first included in neonatal mass screening in the 1990s, the disease severity varies. Thus, determining the specific level of PCC activity is considered to be helpful to grasp the severity of PA. We developed a new PCC assay method by the determination of methylmalonyl-CoA, which is formed by an enzyme reaction using peripheral lymphocytes, based on ultra high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). With methylmalonyl-CoA concentrations of 0.05, 0.5, and 5μmol/L, the intra-assay coefficients of variation (CVs) were 8.2%, 8.7%, and 5.1%, respectively, and the inter-assay CVs were 13.6%, 10.5%, and 5.9%, respectively. The PCC activities of 20 healthy individuals and 6 PA patients were investigated with this assay. Methylmalonyl-CoA was not detected in one PA patient with a severe form of the disease, but the remaining PA patients with mild disease showed residual activities (3.3-7.8%). These results demonstrate that determination of PCC activity with this assay would be useful to distinguish between mild and severe cases of PA to help choose an appropriate treatment plan.

  5. Purification and characterization of benzoate-coenzyme A ligase and 2-aminobenzoate-coenzyme A ligases from a denitrifying Pseudomonas sp.

    PubMed Central

    Altenschmidt, U; Oswald, B; Fuchs, G

    1991-01-01

    The enzymes catalyzing the formation of coenzyme A (CoA) thioesters of benzoate and 2-aminobenzoate were studied in a denitrifying Pseudomonas sp. anaerobically grown with these aromatic acids and nitrate as sole carbon and energy sources. Three different rather specific aromatic acyl-CoA ligases, E1, E2, and E3, were found which catalyze the formation of CoA thioesters of benzoate, fluorobenzoates, and 2-aminobenzoate. ATP is cleaved into AMP and pyrophosphate. The enzymes were purified, their N-terminal amino acid sequences were determined, and their catalytic and molecular properties were studied. Cells anaerobically grown on benzoate and nitrate contain one CoA ligase (AMP forming) for benzoic acid (E1). It is a homodimer of Mr 120,000 which prefers benzoate as a substrate but shows some activity also with 2-aminobenzoate and fluorobenzoates, although with lower Km. Cells anaerobically grown on 2-aminobenzoate and nitrate contain three different CoA ligases for aromatic acids. The first one is identical with benzoate-CoA ligase (E1). The second enzyme is a 2-aminobenzoate-CoA ligase (E2). It is a monomer of Mr 60,000 which prefers 2-aminobenzoate but also activates benzoate, fluorobenzoates and, less effectively, 2-methylbenzoate, with lower affinities to the latter substrates. The enzymes E1 and E2 have similar activity levels; a third minor CoA ligase activity is due to a different 2-aminobenzoate-CoA ligase. The enzyme (E3) is a monomer of Mr, 65,000 which 2-aminobenzoate pathway (U. Altenschmidt, C. Eckerskorn, and G. Fuchs, Eur. J. Biochem. 194:647-653, 1990); apparently, it is not completely repressed under anaerobic conditions and therefore also is induced to a small extent by 2-aminobenzoate under anaerobic growth conditions. Images PMID:1885526

  6. Cloning and expression of clostridium acetobutylicum ATCC 824 acetoacetyl-coenzyme A:acetate/butyrate:coenzyme A-transferase in Escherichia coli

    SciTech Connect

    Cary, J.W.; Petersen, D.J.; Bennett, G.N. ); Papoutsakis, E.T. )

    1990-06-01

    Coenzyme A (CoA)-transferase (acetoacetyl-CoA:acetate/butyrate:CoA-transferase (butyrate-acetoacetate CoA-transferase) (EC 2.8.3.9)) of Clostridium acetobutylicum ATCC 824 is an important enzyme in the metabolic shift between the acid-producing and solvent-forming states of this organism. The genes encoding the two subunits of this enzyme have been cloned and subsequent subcloning experiments established the position of the structural genes for CoA-transferase. Complementation of Escherichia coli ato mutants with the recombinant plasmid pCoAT4 (pUC19 carrying a 1.8-kilobase insert of C. acetobutylicum DNA encoding CoA-transferase activity) enabled the transformants to grow on butyrate as a sole carbon source. Despite the ability of CoA-transferase to complement the ato defect in E. coli mutants, Southern blot and Western blot (immunoblot) analyses showed showed that neither the C. acetobutylicum genes encoding CoA-transferase nor the enzyme itself shared any apparent homology with its E. coli counterpart. Polypeptides of M{sub r} of the purified CoA-transferase subunits were observed by Western blot and maxicell analysis of whole-cell extracts of E.coli harboring pCoAT4. The proximity and orientation of the genes suggest that the genes encoding the two subunits of CoA-transferase may form an operon similar to that found in E. coli. In the plasmid, however, transcription appears to be primarily from the lac promoter of the vector.

  7. The crystal structure of D-mandelate dehydrogenase reveals its distinct substrate and coenzyme recognition mechanisms from those of 2-ketopantoate reductase.

    PubMed

    Miyanaga, Akimasa; Fujisawa, Shinsuke; Furukawa, Nayuta; Arai, Kazuhito; Nakajima, Masahiro; Taguchi, Hayao

    2013-09-13

    D-Mandelate dehydrogenases (D-ManDHs), belonging to a new d-2-hydroxyacid dehydrogenase family, catalyze the conversion between benzoylformate and d-mandelate using NAD as a coenzyme. We determined the first D-ManDH structure, that of ManDH2 from Enterococcus faecalis IAM10071. The overall structure showed ManDH2 has a similar fold to 2-ketopantoate reductase (KPR), which catalyzes the conversion of 2-ketopantoate to d-pantoate using NADP as a coenzyme. They share conserved catalytic residues, indicating ManDH2 has the same reaction mechanism as KPR. However, ManDH2 exhibits significant structural variations in the coenzyme and substrate binding sites compared to KPR. These structural observations could explain their different coenzyme and substrate specificities.

  8. Serum paraoxonase 1 status and its association with atherogenic indexes in gentamicin-induced nephrotoxicity in rats treated with coenzyme Q10.

    PubMed

    Ahmadvand, Hassan; Ghasemi Dehnoo, Maryam; Dehghani, Akram; Bagheri, Shahrokh; Cheraghi, Rooh Angiz

    2014-04-01

    Coenzyme Q10 is a natural antioxidant and scavenger of free radicals. In the present study, we examined the effect of coenzyme Q10 on paraoxonase 1 (PON1) activity, lipid profile, atherogenic indexes and relationship of PON 1 activity by high-density lipoprotein (HDL) and atherogenic indexes in gentamicin (GM)-induced nephrotoxicity rats. Thirty Sprague-Dawley rats were divided into three groups to receive saline; GM, 100 mg/kg/d; and GM plus coenzyme Q10 by 15 mg/kg i.p daily, respectively. After 12 days, animals were anaesthetized, blood samples were also collected before killing to measure the levels of triglyceride (TG), cholesterol (C), low-density lipoprotein (LDL), very low density lipoprotein (VLDL), HDL, atherogenic indexes and the activities of PON1 of all groups were analyzed. Data were analyzed by non-parametric Mann-Whitney test (using SPSS 13 software). Coenzyme Q10 significantly decreased TG, C, LDL, VLDL, atherogenic index, atherogenic coefficient and cardiac risk ratio. HDL level and PON1 activity were significantly increased when treated with coenzyme Q10. Also, the activity of PON 1 correlated positively with HDL and negatively with atherogenic coefficient, cardiac risk ratio 1 and cardiac risk ratio 2. This study showed that coenzyme Q10 exerts beneficial effects on PON1 activity, lipid profile, atherogenic index and correlation of PON 1 activity with HDL and atherogenic index in GM -induced nephrotoxicity rats.

  9. The Protective Effects of Alpha-Lipoic Acid and Coenzyme Q10 Combination on Ovarian Ischemia-Reperfusion Injury: An Experimental Study.

    PubMed

    Tuncer, Ahmet Ali; Bozkurt, Mehmet Fatih; Koken, Tulay; Dogan, Nurhan; Pektaş, Mine Kanat; Baskin Embleton, Didem

    2016-01-01

    Objective. This study aims to evaluate whether alpha-lipoic acid and/or coenzyme Q10 can protect the prepubertal ovarian tissue from ischemia-reperfusion injury in an experimental rat model of ovarian torsion. Materials and Methods. Forty-two female preadolescent Wistar-Albino rats were divided into 6 equal groups randomly. The sham group had laparotomy without torsion; the other groups had torsion/detorsion procedure. After undergoing torsion, group 2 received saline, group 3 received olive oil, group 4 received alpha-lipoic acid, group 5 received coenzyme Q10, and group 6 received both alpha-lipoic acid and coenzyme Q10 orally. The oxidant-antioxidant statuses of these groups were compared using biochemical measurement of oxidized/reduced glutathione, glutathione peroxidase and malondialdehyde, pathological evaluation of damage and apoptosis within the ovarian tissue, and immunohistochemical assessment of nitric oxide synthase. Results. The left ovaries of the alpha-lipoic acid + coenzyme Q10 group had significantly lower apoptosis scores and significantly higher nitric oxide synthase content than the left ovaries of the control groups. The alpha-lipoic acid + coenzyme Q10 group had significantly higher glutathione peroxidase levels and serum malondialdehyde concentrations than the sham group. Conclusions. The combination of alpha-lipoic acid and coenzyme Q10 has beneficial effects on oxidative stress induced by ischemia-reperfusion injury related to ovarian torsion.

  10. The Protective Effects of Alpha-Lipoic Acid and Coenzyme Q10 Combination on Ovarian Ischemia-Reperfusion Injury: An Experimental Study

    PubMed Central

    Bozkurt, Mehmet Fatih; Koken, Tulay; Dogan, Nurhan; Pektaş, Mine Kanat; Baskin Embleton, Didem

    2016-01-01

    Objective. This study aims to evaluate whether alpha-lipoic acid and/or coenzyme Q10 can protect the prepubertal ovarian tissue from ischemia-reperfusion injury in an experimental rat model of ovarian torsion. Materials and Methods. Forty-two female preadolescent Wistar-Albino rats were divided into 6 equal groups randomly. The sham group had laparotomy without torsion; the other groups had torsion/detorsion procedure. After undergoing torsion, group 2 received saline, group 3 received olive oil, group 4 received alpha-lipoic acid, group 5 received coenzyme Q10, and group 6 received both alpha-lipoic acid and coenzyme Q10 orally. The oxidant-antioxidant statuses of these groups were compared using biochemical measurement of oxidized/reduced glutathione, glutathione peroxidase and malondialdehyde, pathological evaluation of damage and apoptosis within the ovarian tissue, and immunohistochemical assessment of nitric oxide synthase. Results. The left ovaries of the alpha-lipoic acid + coenzyme Q10 group had significantly lower apoptosis scores and significantly higher nitric oxide synthase content than the left ovaries of the control groups. The alpha-lipoic acid + coenzyme Q10 group had significantly higher glutathione peroxidase levels and serum malondialdehyde concentrations than the sham group. Conclusions. The combination of alpha-lipoic acid and coenzyme Q10 has beneficial effects on oxidative stress induced by ischemia-reperfusion injury related to ovarian torsion. PMID:27597986

  11. Redesign of the coenzyme specificity in L-lactate dehydrogenase from bacillus stearothermophilus using site-directed mutagenesis and media engineering.

    PubMed

    Holmberg, N; Ryde, U; Bülow, L

    1999-10-01

    L-lactate dehydrogenase (LDH) from Bacillus stearothermophilus is a redox enzyme which has a strong preference for NADH over NADPH as coenzyme. To exclude NADPH from the coenzyme-binding pocket, LDH contains a conserved aspartate residue at position 52. However, this residue is probably not solely responsible for the NADH specificity. In this report we examine the possibilities of altering the coenzyme specificity of LDH by introducing a range of different point mutations in the coenzyme-binding domain. Furthermore, after choosing the mutant with the highest selectivity for NADPH, we also investigated the possibility of further altering the coenzyme specificity by adding an organic solvent to the reaction mixture. The LDH mutant, I51K:D52S, exhibited a 56-fold increased specificity to NADPH over the wild-type LDH in a reaction mixture containing 15% methanol. Furthermore, the NADPH turnover number of this mutant was increased almost fourfold as compared with wild-type LDH. To explain the altered coenzyme specificity exhibited by the D52SI51K double mutant, molecular dynamics simulations were performed.

  12. Mechanism of the neuroprotective role of coenzyme Q10 with or without L-dopa in rotenone-induced parkinsonism.

    PubMed

    Abdin, Amany A; Hamouda, Hala E

    2008-12-01

    Current treatment options for parkinsonism as a neurodegenerative disease are limited and still mainly symptomatic and lack significant disease-modifying effect. Understanding its molecular pathology and finding the cause of dopaminergic cell loss will lead to exploring therapies that could prevent and cure the disease. Mitochondrial dysfunction was found to stimulate releasing of reactive oxygen species (ROS) with subsequent induction of apoptotic neuronal cell death. The aim of the present study was to throw the light on the role of coenzyme Q10 with or without L-dopa in an experimental model of parkinsonism induced by rotenone in rats. The present work showed that rotenone (2.5 mg/kg/day i.p. for 60 days) induced a model of parkinsonism (group II) resembling the basic findings in human characterized by bradykinesia and rigidity manifested as an increase in catalepsy score (detected after 20 days with bad prognosis after 60 days) with marked decrease in striatal dopamine levels. This model confirmed the implication of mitochondrial-apoptotic pathway in the pathogenesis of parkinsonism as there was a decrease in levels of striatal complex I activity and ATP as well as extreme overexpression of the antiapoptotic protein Bcl-2, and also exhibited the role of coenzyme Q10 where its plasma and striatal levels were found to be decreased in comparison to the normal control rats (group I). This proposed pathogenesis was evidenced by the significant correlation between catalepsy score and the neurochemical parameters obtained in the current work. The treated groups started to receive the drug(s) after 20 days from induction of parkinsonism and continued to complete for 60 days. Oral administration of Co Q10 in a low dose 200 mg/kg/day (group III) or a high dose 600 mg/kg/day (group IV), resulted in amelioration of the mitochondrial induced apoptosis by dose-dependent restoration of striatal complex I activity, ATP levels with temperate increase in expression of Bcl-2 as

  13. Stereochemical course of methyl transfer from methanol to methyl coenzyme M in cell-free extracts of methanosarcina barkeri

    SciTech Connect

    Zydowsky, L.D.; Zydowsky, T.M.; Haas, E.S.; Brown, J.W.; Reeve, J.N.; Floss, H.G.

    1987-12-09

    The transformation of the methyl group of methanol into methyl coenzyme M proceeds with net retention of methyl group configuration and without significant racemization. This is consistent with a proposed mechanism in which the methyl group is transferred from methanol first to the cobalt of the corrinoid enzyme MT/sub 1/ and then to the sulfur of coenzyme M. This resembles the transfer of the methyl group of methyltetrahydrofolate to homocysteine, catalyzed by the B/sub 12/-dependent methionine synthase from E. coli, which the authors have demonstrated also occurs with net retention of methyl group configuration. Both reactions pose the same question of how a relatively inert bond, the C-O bond of methyltetrahydrofolate in the case of methionine synthase, is cleaved in the transfer of a methyl group.

  14. Autonomous folding of the excised coenzyme-binding domain of D-glyceraldehyde 3-phosphate dehydrogenase from Thermotoga maritima.

    PubMed Central

    Jecht, M.; Tomschy, A.; Kirschner, K.; Jaenicke, R.

    1994-01-01

    An important question in protein folding is whether compact substructures or domains are autonomous units of folding and assembly. The protomer of the tetrameric D-glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic bacterium Thermotoga maritima has a complex coenzyme-binding domain, in which residues 1-146 form a compact substructure with the last 31 residues (313-333). Here it is shown that the gene of a single-chain protein can be expressed in Escherichia coli after deleting the 163 codons corresponding to the interspersed catalytic domain (150-312). The purified gene product is a soluble, monomeric protein that binds both NAD+ and NADH strongly and possesses the same unfolding transition induced by guanidinium chloride as the native tetramer. The autonomous folding of the coenzyme-binding domain has interesting implications for the folding, assembly, function, and evolution of the native enzyme. PMID:8019412

  15. Coenzyme F430, quantification and isotope analysis from the Eel River Basin California

    NASA Astrophysics Data System (ADS)

    Bird, L. R.; Fulton, J. M.; Dawson, K.; Orphan, V. J.; Freeman, K. H.

    2012-12-01

    Large amounts of methane are oxidized by communities of methanotrophic archaea and sulphate-reducing bacteria, preventing this greenhouse gas from reaching the atmosphere (Orphan et al., 2001; Scheller et al., 2010). Methyl-coenzyme M reductase, an enzyme traditionally associated with methanogenesis, has recently been linked to the anaerobic oxidation of methane suggesting methane oxidation follows a pathway similar to reverse methanogenesis. Coenzyme F430, a tetrapyrrole-nickel complex within the active site of methyl-coenzyme M, is used in methanogenesis and is hypothesized to play a key role in archaeal methanotrophy (Scheller et al., 2010). We recently developed a method to extract and isolate F430 from natural sediments so it can be purified for carbon and nitrogen stable isotope analysis. Sediments are extracted using an ultrasonic homogenizer, first in water (pH 7), then twice in dilute formic acid (pH 3). The combined extract is neutralized and the F430-containing fraction is isolated using Sephadex and Amberlite column chromatography. Further purification is performed using two dimensional high performance liquid chromatography, first with a reverse phase C-18 column followed by separation on a ThermoFisher Hypercarb column. F430 is then quantified using photo diode array detection with fractions collected for isotope analysis using a nano-scale elemental analyzer isotope ratio mass spectrometer (nano-EA-IRMS; Polissar et al., 2009). Compound identity and purity are confirmed using molar C:N ratios, UV absorbance and MSn detection of the parent ion (m/z 905). Here, we report F430 concentrations and isotopic data determined from active seep sediment cores from the Eel River Basin (California), a site where the anoxic oxidation of methane occurs. A spike in the concentration of F430 is observed at the 3-6 cm depth horizon corresponding with peak abundance in ANME-2/Desulfosarcina/Desulfococcus aggregate counts. Carbon isotope values of F430 are significantly

  16. The C-terminal extension of bacterial flavodoxin-reductases: involvement in the hydride transfer mechanism from the coenzyme.

    PubMed

    Bortolotti, Ana; Sánchez-Azqueta, Ana; Maya, Celia M; Velázquez-Campoy, Adrián; Hermoso, Juan A; Medina, Milagros; Cortez, Néstor

    2014-01-01

    To study the role of the mobile C-terminal extension present in bacterial class of plant type NADP(H):ferredoxin reductases during catalysis, we generated a series of mutants of the Rhodobacter capsulatus enzyme (RcFPR). Deletion of the six C-terminal amino acids beyond alanine 266 was combined with the replacement A266Y, emulating the structure present in plastidic versions of this flavoenzyme. Analysis of absorbance and fluorescence spectra suggests that deletion does not modify the general geometry of FAD itself, but increases exposure of the flavin to the solvent, prevents a productive geometry of FAD:NADP(H) complex and decreases the protein thermal stability. Although the replacement A266Y partially coats the isoalloxazine from solvent and slightly restores protein stability, this single change does not allow formation of active charge-transfer complexes commonly present in the wild-type FPR, probably due to restraints of C-terminus pliability. A proton exchange process is deduced from ITC measurements during coenzyme binding. All studied RcFPR variants display higher affinity for NADP(+) than wild-type, evidencing the contribution of the C-terminus in tempering a non-productive strong (rigid) interaction with the coenzyme. The decreased catalytic rate parameters confirm that the hydride transfer from NADPH to the flavin ring is considerably hampered in the mutants. Although the involvement of the C-terminal extension from bacterial FPRs in stabilizing overall folding and bent-FAD geometry has been stated, the most relevant contributions to catalysis are modulation of coenzyme entrance and affinity, promotion of the optimal geometry of an active complex and supply of a proton acceptor acting during coenzyme binding.

  17. Simultaneous Analysis of Major Coenzymes of Cellular Redox Reactions and Energy Using ex Vivo (1)H NMR Spectroscopy.

    PubMed

    Nagana Gowda, G A; Abell, Lauren; Lee, Chi Fung; Tian, Rong; Raftery, Daniel

    2016-05-03

    Coenzymes of cellular redox reactions and cellular energy mediate biochemical reactions fundamental to the functioning of all living cells. Despite their immense interest, no simple method exists to gain insights into their cellular concentrations in a single step. We show that a simple (1)H NMR experiment can simultaneously measure oxidized and reduced forms of nicotinamide adenine dinucleotide (NAD(+) and NADH), oxidized and reduced forms of nicotinamide adenine dinucleotide phosphate (NADP(+) and NADPH), and adenosine triphosphate (ATP) and its precursors, adenosine diphosphate (ADP) and adenosine monophosphate (AMP), using mouse heart, kidney, brain, liver, and skeletal muscle tissue extracts as examples. Combining 1D/2D NMR experiments, chemical shift libraries, and authentic compound data, reliable peak identities for these coenzymes have been established. To assess this methodology, cardiac NADH and NAD(+) ratios/pool sizes were measured using mouse models with a cardiac-specific knockout of the mitochondrial Complex I Ndufs4 gene (cKO) and cardiac-specific overexpression of nicotinamide phosphoribosyltransferase (cNAMPT) as examples. Sensitivity of NAD(+) and NADH to cKO or cNAMPT was observed, as anticipated. Time-dependent investigations showed that the levels of NADH and NADPH diminish by up to ∼50% within 24 h; concomitantly, NAD(+) and NADP(+) increase proportionately; however, degassing the sample and flushing the sample tubes with helium gas halted such changes. The analysis protocol along with the annotated characteristic fingerprints for each coenzyme is provided for easy identification and absolute quantification using a single internal reference for routine use. The ability to visualize the ubiquitous coenzymes fundamental to cellular functions, simultaneously and reliably, offers a new avenue to interrogate the mechanistic details of cellular function in health and disease.

  18. On the assignment of nickel oxidation states of the Ox1,Ox2 forms of methyl-coenzyme M reductase

    SciTech Connect

    Telser, J.; Horng, Y.C.; Becker, D.F.; Hoffman, B.M.; Ragsdale, S.W.

    2000-01-12

    Methyl-coenzyme M reductase (MCR) catalyzes the chemical step of methane formation by methanogenic organisms. The reaction involves the two-electron reduction of CH{sub 3}S-CoM by N-7-mercaptoheptanoylthreoinine phosphate (CoB-SH). The authors have employed 35 GHz EPR and ENDOR spectroscopy to resolve the oxidation state of Ni in ox1, ox2 and red1 forms of MCR, isolated from methanobacterium thermoautotrophicum strain Marburg and prepared as described previously.

  19. Effects of immunostimulation with OK432, coenzyme Q10, or levamisole on dimethylhydrazine-induced colonic carcinogenesis in rats.

    PubMed

    Suzuki, H; Yamamoto, J; Iwata, Y; Matsumoto, K; Iriyama, K

    1986-03-01

    Effects of immunostimulation with OK432, Coenzyme Q10 (Co-Q10), or levamisole on dimethylhydrazine (DMH)-induced colonic carcinogenesis were investigated in 45 Donryu-rats. The manipulation with one of these immunopotentiators did not prevent DMH-induced colonic carcinogenesis in these rats. However, the number of tumors was significantly reduced and the incidence of invasive carcinomas decreased by immunostimulation. The treatment also reduced the number of lesions with epithelial dysplasia within the flat colonic mucosa.

  20. Simultaneous Analysis of Major Coenzymes of Cellular Redox Reactions and Energy Using ex Vivo 1H NMR Spectroscopy

    PubMed Central

    2016-01-01

    Coenzymes of cellular redox reactions and cellular energy mediate biochemical reactions fundamental to the functioning of all living cells. Despite their immense interest, no simple method exists to gain insights into their cellular concentrations in a single step. We show that a simple 1H NMR experiment can simultaneously measure oxidized and reduced forms of nicotinamide adenine dinucleotide (NAD+ and NADH), oxidized and reduced forms of nicotinamide adenine dinucleotide phosphate (NADP+ and NADPH), and adenosine triphosphate (ATP) and its precursors, adenosine diphosphate (ADP) and adenosine monophosphate (AMP), using mouse heart, kidney, brain, liver, and skeletal muscle tissue extracts as examples. Combining 1D/2D NMR experiments, chemical shift libraries, and authentic compound data, reliable peak identities for these coenzymes have been established. To assess this methodology, cardiac NADH and NAD+ ratios/pool sizes were measured using mouse models with a cardiac-specific knockout of the mitochondrial Complex I Ndufs4 gene (cKO) and cardiac-specific overexpression of nicotinamide phosphoribosyltransferase (cNAMPT) as examples. Sensitivity of NAD+ and NADH to cKO or cNAMPT was observed, as anticipated. Time-dependent investigations showed that the levels of NADH and NADPH diminish by up to ∼50% within 24 h; concomitantly, NAD+ and NADP+ increase proportionately; however, degassing the sample and flushing the sample tubes with helium gas halted such changes. The analysis protocol along with the annotated characteristic fingerprints for each coenzyme is provided for easy identification and absolute quantification using a single internal reference for routine use. The ability to visualize the ubiquitous coenzymes fundamental to cellular functions, simultaneously and reliably, offers a new avenue to interrogate the mechanistic details of cellular function in health and disease. PMID:27043450

  1. Rational design and synthesis of substrate-product analogue inhibitors of α-methylacyl-coenzyme A racemase from Mycobacterium tuberculosis.

    PubMed

    Pal, Mohan; Khanal, Mandar; Marko, Ryan; Thirumalairajan, Srinath; Bearne, Stephen L

    2016-02-14

    2,2-Bis(4-isobutylphenyl)propanoyl-CoA and 2,2-bis(4-t-butylphenyl)propanoyl-CoA are rationally designed, gem-disubstituted substrate-product analogues that competitively inhibit α-methylacyl-coenzyme A racemase from Mycobacterium tuberculosis with Ki values of 16.9 ± 0.6 and 21 ± 4 μM, respectively, exceeding the enzyme's affinity for the substrate by approximately 5-fold.

  2. A Randomized Trial of Coenzyme Q10 in Patients with Confirmed Statin Myopathy

    PubMed Central

    Taylor, Beth A.; Lorson, Lindsay; White, C. Michael; Thompson, Paul D.

    2014-01-01

    Background Coenzyme Q10 (CoQ10) supplementation is the most popular therapy for statin myalgia among both physicians and patients despite limited and conflicting evidence of its efficacy. Objective This study examined the effect of coenzyme Q10 (CoQ10) supplementation on simvastatin-associated muscle pain, muscle strength and aerobic performance in patients with confirmed statin myalgia. Methods Statin myalgia was confirmed in 120 patients with prior symptoms of statin myalgia using an 8-week randomized, double-blind crossover trial of simvastatin 20 mg/d and placebo. Forty-one subjects developed muscle pain with simvastatin but not with placebo and were randomized to simvastatin 20 mg/d combined with CoQ10 (600 mg/d ubiquinol) or placebo for 8 weeks. Muscle pain (Brief Pain Inventory [BPI]), time to pain onset, arm and leg muscle strength, and maximal oxygen uptake (VO2max) were measured before and after each treatment. Results Serum CoQ10 increased from 1.3±0.4 to 5.2±2.3 mcg/mL with simvastatin and CoQ10, but did not increase with simvastatin and placebo (1.3±0.3 to 0.8±0.2) (p<0.05). BPI pain severity and interference scores increased with simvastatin therapy (both p<0.01), irrespective of CoQ10 assignment (p=0.53 and 0.56). There were no changes in muscle strength or VO2max with simvastatin with or without CoQ10 (all p>0.10). Marginally more subjects reported pain with CoQ10 (14 of 20 vs 7 of 18; p=0.05). There was no difference in time to pain onset in the CoQ10 (3.0±2.0 weeks) vs. placebo (2.4±2.1 wks) groups (p=0.55). A similar lack of CoQ10 effect was observed in 24 subjects who were then crossed over to the alternative treatment. Conclusions Only 36% of patients complaining of statin myalgia develop symptoms during a randomized, double-blind crossover of statin vs placebo. CoQ10 supplementation does not reduce muscle pain in patients with statin myalgia. Trial Registration NCT01140308; www.clinicaltrials.gov PMID:25545331

  3. Properties of the two isoenzymes of methyl-coenzyme M reductase in Methanobacterium thermoautotrophicum.

    PubMed

    Bonacker, L G; Baudner, S; Mörschel, E; Böcher, R; Thauer, R K

    1993-10-15

    Methyl-coenzyme M reductase (MCR) catalyses the methane-forming step in the energy metabolism of methanogenic Archaea. It brings about the reduction of methyl-coenzyme M (CH3-S-CoM) by 7-mercaptoheptanoylthreonine phosphate (H-S-HTP). Methanobacterium thermoautotrophicum contains two isoenzymes of MCR, designated MCR I and MCR II, which are expressed differentially under different conditions of growth. These two isoenzymes have been separated, purified and their catalytic and spectroscopic properties determined. Initial-velocity measurements of the two-substrate reaction showed that the kinetic mechanism for both isoenzymes involved ternary-complex formation. Double reciprocal plots of initial rates versus the concentration of either one of the two substrates at different constant concentrations of the other substrate were linear and intersected on the abcissa to the left of the 1/v axis. The two purified isoenzymes differed in their Km values for H-S-HTP and for CH3-S-CoM and in Vmax. MCR I displayed a Km for H-S-HTP of 0.1-0.3 mM, a Km for CH3-S-CoM of 0.6-0.8 mM and a Vmax of about 6 mumol.min-1 x mg-1 (most active preparation). MCR II showed a Km for H-S-HTP of 0.4-0.6 mM, a Km for CH3-S-CoM of 1.3-1.5 mM and a Vmax of about 21 mumol.min-1 x mg-1 (most active preparation). The pH optimum of MCR I was 7.0-7.5 and that of MCR II 7.5-8.0. Both isoenzymes exhibited very similar temperature activity optima and EPR properties. The location of MCR I and of MCR II within the cell, determined via immunogold labeling, was found to be essentially identical. The possible basis for the existence of MCR isoenzymes in M. thermoautotrophicum is discussed.

  4. The reaction mechanism of methyl-coenzyme M reductase: How an enzyme enforces strict binding order

    SciTech Connect

    Wongnate, Thanyaporn; Ragsdale, Stephen W.

    2015-02-17

    Methyl-coenzyme M reductase (MCR) is a nickel tetrahydrocorphinoid (coenzyme F430) containing enzyme involved in the biological synthesis and anaerobic oxidation of methane. MCR catalyzes the conversion of methyl-2-mercaptoethanesulfonate (methyl-SCoM) and N-7-mercaptoheptanoylthreonine phosphate (CoB7SH) to CH4 and the mixed disulfide CoBS-SCoM. In this study, the reaction of MCR from Methanothermobacter marburgensis, with its native substrates was investigated using static binding, chemical quench, and stopped-flow techniques. Rate constants were measured for each step in this strictly ordered ternary complex catalytic mechanism. Surprisingly, in the absence of the other substrate, MCR can bind either substrate; however, only one binary complex (MCR·methyl-SCoM) is productive whereas the other (MCR·CoB7SH) is inhibitory. Moreover, the kinetic data demonstrate that binding of methyl-SCoM to the inhibitory MCR·CoB7SH complex is highly disfavored (Kd = 56 mM). However, binding of CoB7SH to the productive MCR·methyl-SCoM complex to form the active ternary complex (CoB7SH·MCR(NiI)·CH3SCoM) is highly favored (Kd = 79 μM). Only then can the chemical reaction occur (kobs = 20 s-1 at 25 °C), leading to rapid formation and dissociation of CH4 leaving the binary product complex (MCR(NiII)·CoB7S-·SCoM), which undergoes electron transfer to regenerate Ni(I) and the final product CoBS-SCoM. In conclusion, this first rapid kinetics study of MCR with its natural substrates describes how an enzyme can enforce a strictly ordered ternary complex mechanism and serves as a template for identification of the reaction intermediates.

  5. Nanoencapsulation of coenzyme Q10 and vitamin E acetate protects against UVB radiation-induced skin injury in mice.

    PubMed

    Pegoraro, Natháli S; Barbieri, Allanna V; Camponogara, Camila; Mattiazzi, Juliane; Brum, Evelyne S; Marchiori, Marila C L; Oliveira, Sara M; Cruz, Letícia

    2017-02-01

    This study aimed to investigate the feasibility of producing semisolid formulations based on nanocapsule suspensions containing the association of the coenzyme Q10 and vitamin E acetate by adding gellan gum (2%) to the suspensions. Furthermore, we studied their application as an alternative for the treatment of inflammation induced by ultraviolet B (UVB) radiation. For this, an animal model of injury induced by UVB-radiation was employed. All semisolids presented pH close to 5.5, drug content above 95% and mean diameter on the nanometric range, after redispersion in water. Besides, the semisolids presented non-Newtonian flow with pseudoplastic behavior and suitable spreadability factor values. The results also showed that the semisolid containing coenzyme Q10-loaded nanocapsules with higher vitamin E acetate concentration reduced in 73±8% the UVB radiation-induced ear edema. Moreover, all formulations tested were able to reduce inflammation parameters evaluated through MPO activity and histological procedure on injured tissue and the semisolids containing the nanoencapsulated coenzyme Q10 reduced oxidative parameters assessment through the non-protein thiols levels and lipid peroxidation. This way, the semisolids based on nanocapsules may be considered a promising approach for the treatment and prevention of skin inflammation diseases.

  6. 4-Coumarate:coenzyme A ligase and isoperoxidase expression in Zinnia mesophyll cells induced to differentiate into tracheary elements

    NASA Technical Reports Server (NTRS)

    Church, D. L.; Galston, A. W.

    1988-01-01

    When cultured in inductive medium containing adequate auxin and cytokinin, isolated mesophyll cells of Zinnia elegans L. cv Envy differentiate into tracheary elements with lignified secondary wall thickenings. Differentiation does not occur when cells are cultured in control medium, which has reduced levels of auxin and/or cytokinin. The activities of two enzymes involved in lignin synthesis, 4-coumarate:coenzyme A ligase and peroxidase, were examined. An induction-specific cationic isoperoxidase, visualized by low pH polyacrylamide gel electrophoresis, is detectable in soluble and wall fractions of cultured Zinnia cells long before tracheary elements visibly differentiate and is thus an early marker of differentiation. Compounds (such as antiauxins, anticytokinins, and tunicamycin) that inhibit or delay differentiation alter the expression of this isoperoxidase. 4-Coumarate:coenzyme A ligase activity increases dramatically only as cells differentiate. Together, these results suggest that the onset of lignification in differentiating Zinnia cells might be controlled by the availability of precursors synthesized by way of 4-coumarate:coenzyme A ligase. These precursors would then be polymerized into lignin in the cell wall by the induction-specific isoperoxidase.

  7. Reversal of coenzyme specificity of 2,3-butanediol dehydrogenase from Saccharomyces cerevisae and in vivo functional analysis.

    PubMed

    Ehsani, Maryam; Fernández, Maria R; Biosca, Josep A; Dequin, Sylvie

    2009-10-01

    Saccharomyces cerevisiae NAD(H)-dependent 2,3-butanediol dehydrogenase (Bdh1), a medium chain dehydrogenase/reductase is the main enzyme catalyzing the reduction of acetoin to 2,3-butanediol. In this work we focused on altering the coenzyme specificity of Bdh1 from NAD(H) to NADP(H). Based on homology studies and the crystal structure of the NADP(H)-dependent yeast alcohol dehydrogenase Adh6, three adjacent residues (Glu(221), Ile(222), and Ala(223)) were predicted to be involved in the coenzyme specificity of Bdh1 and were altered by site-directed mutagenesis. Coenzyme reversal of Bdh1 was obtained with double Glu221Ser/Ile222Arg and triple Glu221Ser/Ile222Arg/Ala223Ser mutants. The performance of the triple mutant for NADPH was close to that of native Bdh1 for NADH. The three engineered mutants were able to restore the growth of a phosphoglucose isomerase deficient strain (pgi), which cannot grow on glucose unless an alternative NADPH oxidizing system is provided, thus demonstrating their in vivo functionality. These mutants are interesting tools to reduce the excess of acetoin produced by engineered brewing or wine yeasts overproducing glycerol. In addition, they represent promising tools for the manipulation of the NADP(H) metabolism and for the development of a powerful catalyst in biotransformations requiring NADPH regeneration.

  8. Molecular mechanisms of the non-coenzyme action of thiamin in brain: biochemical, structural and pathway analysis

    PubMed Central

    Mkrtchyan, Garik; Aleshin, Vasily; Parkhomenko, Yulia; Kaehne, Thilo; Luigi Di Salvo, Martino; Parroni, Alessia; Contestabile, Roberto; Vovk, Andrey; Bettendorff, Lucien; Bunik, Victoria

    2015-01-01

    Thiamin (vitamin B1) is a pharmacological agent boosting central metabolism through the action of the coenzyme thiamin diphosphate (ThDP). However, positive effects, including improved cognition, of high thiamin doses in neurodegeneration may be observed without increased ThDP or ThDP-dependent enzymes in brain. Here, we determine protein partners and metabolic pathways where thiamin acts beyond its coenzyme role. Malate dehydrogenase, glutamate dehydrogenase and pyridoxal kinase were identified as abundant proteins binding to thiamin- or thiazolium-modified sorbents. Kinetic studies, supported by structural analysis, revealed allosteric regulation of these proteins by thiamin and/or its derivatives. Thiamin triphosphate and adenylated thiamin triphosphate activate glutamate dehydrogenase. Thiamin and ThDP regulate malate dehydrogenase isoforms and pyridoxal kinase. Thiamin regulation of enzymes related to malate-aspartate shuttle may impact on malate/citrate exchange, responsible for exporting acetyl residues from mitochondria. Indeed, bioinformatic analyses found an association between thiamin- and thiazolium-binding proteins and the term acetylation. Our interdisciplinary study shows that thiamin is not only a coenzyme for acetyl-CoA production, but also an allosteric regulator of acetyl-CoA metabolism including regulatory acetylation of proteins and acetylcholine biosynthesis. Moreover, thiamin action in neurodegeneration may also involve neurodegeneration-related 14-3-3, DJ-1 and β-amyloid precursor proteins identified among the thiamin- and/or thiazolium-binding proteins. PMID:26212886

  9. A nickel hydride complex in the active site of methyl-coenzyme m reductase: implications for the catalytic cycle.

    PubMed

    Harmer, Jeffrey; Finazzo, Cinzia; Piskorski, Rafal; Ebner, Sieglinde; Duin, Evert C; Goenrich, Meike; Thauer, Rudolf K; Reiher, Markus; Schweiger, Arthur; Hinderberger, Dariush; Jaun, Bernhard

    2008-08-20

    Methanogenic archaea utilize a specific pathway in their metabolism, converting C1 substrates (i.e., CO2) or acetate to methane and thereby providing energy for the cell. Methyl-coenzyme M reductase (MCR) catalyzes the key step in the process, namely methyl-coenzyme M (CH3-S-CoM) plus coenzyme B (HS-CoB) to methane and CoM-S-S-CoB. The active site of MCR contains the nickel porphinoid F430. We report here on the coordinated ligands of the two paramagnetic MCR red2 states, induced when HS-CoM (a reversible competitive inhibitor) and the second substrate HS-CoB or its analogue CH3-S-CoB are added to the enzyme in the active MCR red1 state (Ni(I)F430). Continuous wave and pulse EPR spectroscopy are used to show that the MCR red2a state exhibits a very large proton hyperfine interaction with principal values A((1)H) = [-43,-42,-5] MHz and thus represents formally a Ni(III)F430 hydride complex formed by oxidative addition to Ni(I). In view of the known ability of nickel hydrides to activate methane, and the growing body of evidence for the involvement of MCR in "reverse" methanogenesis (anaerobic oxidation of methane), we believe that the nickel hydride complex reported here could play a key role in helping to understand both the mechanism of "reverse" and "forward" methanogenesis.

  10. High-Throughput Screening of Coenzyme Preference Change of Thermophilic 6-Phosphogluconate Dehydrogenase from NADP+ to NAD+

    PubMed Central

    Huang, Rui; Chen, Hui; Zhong, Chao; Kim, Jae Eung; Zhang, Yi-Heng Percival

    2016-01-01

    Coenzyme engineering that changes NAD(P) selectivity of redox enzymes is an important tool in metabolic engineering, synthetic biology, and biocatalysis. Here we developed a high throughput screening method to identify mutants of 6-phosphogluconate dehydrogenase (6PGDH) from a thermophilic bacterium Moorella thermoacetica with reversed coenzyme selectivity from NADP+ to NAD+. Colonies of a 6PGDH mutant library growing on the agar plates were treated by heat to minimize the background noise, that is, the deactivation of intracellular dehydrogenases, degradation of inherent NAD(P)H, and disruption of cell membrane. The melted agarose solution containing a redox dye tetranitroblue tetrazolium (TNBT), phenazine methosulfate (PMS), NAD+, and 6-phosphogluconate was carefully poured on colonies, forming a second semi-solid layer. More active 6PGDH mutants were examined via an enzyme-linked TNBT-PMS colorimetric assay. Positive mutants were recovered by direct extraction of plasmid from dead cell colonies followed by plasmid transformation into E. coli TOP10. By utilizing this double-layer screening method, six positive mutants were obtained from two-round saturation mutagenesis. The best mutant 6PGDH A30D/R31I/T32I exhibited a 4,278-fold reversal of coenzyme selectivity from NADP+ to NAD+. This screening method could be widely used to detect numerous redox enzymes, particularly for thermophilic ones, which can generate NAD(P)H reacted with the redox dye TNBT. PMID:27587230

  11. On the mechanism of biological methane formation: structural evidence for conformational changes in methyl-coenzyme M reductase upon substrate binding.

    PubMed

    Grabarse, W; Mahlert, F; Duin, E C; Goubeaud, M; Shima, S; Thauer, R K; Lamzin, V; Ermler, U

    2001-05-25

    Methyl-coenzyme M reductase (MCR) catalyzes the final reaction of the energy conserving pathway of methanogenic archaea in which methylcoenzyme M and coenzyme B are converted to methane and the heterodisulfide CoM-S-S-CoB. It operates under strictly anaerobic conditions and contains the nickel porphinoid F430 which is present in the nickel (I) oxidation state in the active enzyme. The known crystal structures of the inactive nickel (II) enzyme in complex with coenzyme M and coenzyme B (MCR-ox1-silent) and in complex with the heterodisulfide CoM-S-S-CoB (MCR-silent) were now refined at 1.16 A and 1.8 A resolution, respectively. The atomic resolution structure of MCR-ox1-silent describes the exact geometry of the cofactor F430, of the active site residues and of the modified amino acid residues. Moreover, the observation of 18 Mg2+ and 9 Na+ ions at the protein surface of the 300 kDa enzyme specifies typical constituents of binding sites for either ion. The MCR-silent and MCR-ox1-silent structures differed in the occupancy of bound water molecules near the active site indicating that a water chain is involved in the replenishment of the active site with water molecules. The structure of the novel enzyme state MCR-red1-silent at 1.8 A resolution revealed an active site only partially occupied by coenzyme M and coenzyme B. Increased flexibility and distinct alternate conformations were observed near the active site and the substrate channel. The electron density of the MCR-red1-silent state aerobically co-crystallized with coenzyme M displayed a fully occupied coenzyme M-binding site with no alternate conformations. Therefore, the structure was very similar to the MCR-ox1-silent state. As a consequence, the binding of coenzyme M induced specific conformational changes that postulate a molecular mechanism by which the enzyme ensures that methylcoenzyme M enters the substrate channel prior to coenzyme B as required by the active-site geometry. The three different

  12. Amitriptyline down-regulates coenzyme Q10 biosynthesis in lung cancer cells.

    PubMed

    Ortiz, Tamara; Villanueva-Paz, Marina; Díaz-Parrado, Eduardo; Illanes, Matilde; Fernández-Rodríguez, Ana; Sánchez-Alcázar, José A; de Miguel, Manuel

    2017-02-15

    Amitriptyline, a tricyclic antidepressant, has been proposed as an antitumoral drug in oxidative therapy. Its pro-apoptotic effects, mediated by high reactive oxygen species generation, have been already described. In this study we analysed the effect of amitriptyline on the biosynthesis of coenzyme Q10 (CoQ), an essential component for electron transport and a potent membrane antioxidant involved in redox signaling. We treated H460 cells, a non-small-cell lung cancer cell line, with amitriptyline and we analysed CoQ levels by HPLC and CoQ biosynthesis rate, as well as the enzymes involved in CoQ biosynthesis by real-time PCR and Western blot. Amitriptyline treatment induced a dose-dependent decrease in CoQ levels in tumor cells. CoQ decreased levels were associated with down-regulation of the expression of COQ4 gene, as well as decreased Coq4 and Coq6 protein levels. Our findings suggest that the effect of amitriptyline on CoQ biosynthesis highlights the potential of this drug for antitumoral oxidative therapy.

  13. Is Coenzyme Q10 Effective in Protection against Ulcerative Colitis? An Experimental Study in Rats.

    PubMed

    Ewees, Mohamed Gamal; Messiha, Basim Anwar Shehata; Abo-Saif, Ali Ahmed; Abd El-Latif, Hekma Abd El-Tawab

    2016-01-01

    Coenzyme Q10 (Co-Q10) is a vitamin-like supplement which appears to be safe, with minimal side effects and low drug interaction potential. Co-Q10 is used in the treatment of a variety of disorders related primarily to suboptimal cellular energy metabolism and oxidative injury. Studies supporting the efficacy of Co-Q10 appear most promising for a variety of diseases, including ulcerative colitis (UC). The present investigation aims to elucidate the possible protective effects of Co-Q10 against UC, as induced by the administration of iodoacetamide to adult male albino rats. In our study, Co-Q10 showed potent anti-oxidant and anti-inflammatory activities through a significant increase in catalase activity and glutathione content. In addition, it significantly decreased myeloperoxidase activity, malondialdehyde content and nitrate/nitrite production. These results suggest that Co-Q10 protects against UC in rats via anti-oxidant and anti-inflammatory potentials, and therefore seems promising for use in further clinical trials.

  14. Determination of the coenzyme Q10 status in a large Caucasian study population.

    PubMed

    Onur, Simone; Niklowitz, Petra; Fischer, Alexandra; Jacobs, Gunnar; Lieb, Wolfgang; Laudes, Matthias; Menke, Thomas; Döring, Frank

    2015-01-01

    Coenzyme Q10 (CoQ10 ) exists in a reduced (ubiquinol) and an oxidized (ubiquinone) form in all human tissues and functions, amongst others, in the respiratory chain, redox-cycles, and gene expression. As the status of CoQ10 is an important risk factor for several diseases, here we determined the CoQ10 status (ubiquinol, ubiquinone) in a large Caucasian study population (n = 1,911). The study population covers a wide age range (age: 18-83 years, 43.4% men), has information available on more than 10 measured clinical phenotypes, more than 30 diseases (presence vs. absence), about 30 biomarkers, and comprehensive genetic information including whole-genome SNP typing (>891,000 SNPs). The major aim of this long-term resource in CoQ10 research is the comprehensive analysis of the CoQ10 status with respect to integrated health parameters (i.e., fat metabolism, inflammation), disease-related biomarkers (i.e., liver enzymes, marker for heart failure), common diseases (i.e., neuropathy, myocardial infarction), and genetic risk in humans. Based on disease status, biomarkers, and genetic variants, our cohort is also useful to perform Mendelian randomisation approaches. In conclusion, the present study population is a promising resource to gain deeper insight into CoQ10 status in human health and disease.

  15. Automatic determination of coenzyme Q10 in food using cresyl violet encapsulated into magnetoliposomes.

    PubMed

    Román-Pizarro, Vanessa; Fernández-Romero, Juan Manuel; Gómez-Hens, Agustina

    2017-04-15

    A new type of magnetoliposomes (MLs), containing hydrophobic magnetic-gold nanoparticles and the long wavelength fluorophore cresyl violet, has been used for the determination of coenzyme Q10 (CoQ10). MLs were concentrated just before the detector, using a flow system and an external electromagnet device. The subsequent introduction of Triton X-100 and CoQ10 causes the MLs lysis and the cresyl violet oxidation, obtaining a decrease in the fluorescence signal. The dynamic range of the calibration graph was 0.03-0.50μmolL(-1) CoQ10, and the detection limit was 0.008μmolL(-1). The precision (relative standard deviation) was in the range of 1.3-4.5%. The method showed a sampling frequency of 12h(-1) and was applied to the determination of CoQ10 in several food samples. The results were compared with those obtained using a previously described chromatographic method. Also, recovery values were in the range of 83.5-101.3%.

  16. The Structural Basis of Coenzyme A Recycling in a Bacterial Organelle

    PubMed Central

    Kerfeld, Cheryl A.

    2016-01-01

    Bacterial Microcompartments (BMCs) are proteinaceous organelles that encapsulate critical segments of autotrophic and heterotrophic metabolic pathways; they are functionally diverse and are found across 23 different phyla. The majority of catabolic BMCs (metabolosomes) compartmentalize a common core of enzymes to metabolize compounds via a toxic and/or volatile aldehyde intermediate. The core enzyme phosphotransacylase (PTAC) recycles Coenzyme A and generates an acyl phosphate that can serve as an energy source. The PTAC predominantly associated with metabolosomes (PduL) has no sequence homology to the PTAC ubiquitous among fermentative bacteria (Pta). Here, we report two high-resolution PduL crystal structures with bound substrates. The PduL fold is unrelated to that of Pta; it contains a dimetal active site involved in a catalytic mechanism distinct from that of the housekeeping PTAC. Accordingly, PduL and Pta exemplify functional, but not structural, convergent evolution. The PduL structure, in the context of the catalytic core, completes our understanding of the structural basis of cofactor recycling in the metabolosome lumen. PMID:26959993

  17. Reduction and Methyl Transfer Kinetics of the Alpha Subunit from Acetyl-Coenzyme A Synthase

    SciTech Connect

    Xiangshi Tan; Christopher Sewell; Qingwu Yang; Paul A. Lindahl

    2003-01-15

    OAK-B135 Stopped-flow was used to evaluate the methylation and reduction kinetics of the isolated alpha subunit of acetyl-Coenzyme A synthase from Moorella thermoacetica. This catalytically active subunit contains a novel Ni-X-Fe4S4 cluster and a putative unidentified n =2 redox site called D. The D-site must be reduced for a methyl group to transfer from a corrinoid-iron-sulfur protein, a key step in the catalytic synthesis of acetyl-CoA. The Fe4S4 component of this cluster is also redox active, raising the possibility that it is the D-site or a portion thereof. Results presented demonstrate that the D-site reduces far faster than the Fe4S4 component, effectively eliminating this possibility. Rather, this component may alter catalytically important properties of the Ni center. The D-site is reduced through a pathway that probably does not involve the Fe4S4 component of this active-site cluster.

  18. Investigation of pyridine carboxylic acids in CM2 carbonaceous chondrites: Potential precursor molecules for ancient coenzymes

    NASA Astrophysics Data System (ADS)

    Smith, Karen E.; Callahan, Michael P.; Gerakines, Perry A.; Dworkin, Jason P.; House, Christopher H.

    2014-07-01

    The distribution and abundances of pyridine carboxylic acids (including nicotinic acid) in eight CM2 carbonaceous chondrites (ALH 85013, DOM 03183, DOM 08003, EET 96016, LAP 02333, LAP 02336, LEW 85311, and WIS 91600) were investigated by liquid chromatography coupled to UV detection and high resolution Orbitrap mass spectrometry. We find that pyridine monocarboxylic acids are prevalent in CM2-type chondrites and their abundance negatively correlates with the degree of pre-terrestrial aqueous alteration that the meteorite parent body experienced. We also report the first detection of pyridine dicarboxylic acids in carbonaceous chondrites. Additionally, we carried out laboratory studies of proton-irradiated pyridine in carbon dioxide-rich ices (a 1:1 mixture) to serve as a model of the interstellar ice chemistry that may have led to the synthesis of pyridine carboxylic acids. Analysis of the irradiated ice residue shows that a comparable suite of pyridine mono- and dicarboxylic acids was produced, although aqueous alteration may still play a role in the synthesis (and ultimate yield) of these compounds in carbonaceous meteorites. Nicotinic acid is a precursor to nicotinamide adenine dinucleotide, a likely ancient molecule used in cellular metabolism in all of life, and its common occurrence in CM2 chondrites may indicate that meteorites may have been a source of molecules for the emergence of more complex coenzymes on the early Earth.

  19. High-resolution neutron crystallographic studies of the hydration of the coenzyme cob(II)alamin.

    PubMed

    Jogl, Gerwald; Wang, Xiaoping; Mason, Sax A; Kovalevsky, Andrey; Mustyakimov, Marat; Fisher, Zöe; Hoffman, Christina; Kratky, Christoph; Langan, Paul

    2011-06-01

    The hydration of the coenzyme cob(II)alamin has been studied using high-resolution monochromatic neutron crystallographic data collected at room temperature to a resolution of 0.92 Å on the original D19 diffractometer with a prototype 4° × 64° detector at the high-flux reactor neutron source run by the Institute Laue-Langevin. The resulting structure provides hydrogen-bonding parameters for the hydration of biomacromolecules to unprecedented accuracy. These experimental parameters will be used to define more accurate force fields for biomacromolecular structure refinement. The presence of a hydrophobic bowl motif surrounded by flexible side chains with terminal functional groups may be significant for the efficient scavenging of ligands. The feasibility of extending the resolution of this structure to ultrahigh resolution was investigated by collecting time-of-flight neutron crystallographic data during commissioning of the TOPAZ diffractometer with a prototype array of 14 modular 2° × 21° detectors at the Spallation Neutron Source run by Oak Ridge National Laboratory.

  20. Getting a Handle on the Role of Coenzyme M in Alkene Metabolism

    SciTech Connect

    Krishnakumar, A.M.; Sliwa, D.; Endrizzi, J.A.; Boyd, E.S.; Ensign, S.A.; Peters, J.W.

    2009-05-20

    Coenzyme M (2-mercaptoethanesulfonate; CoM) is one of several atypical cofactors discovered in methanogenic archaea which participate in the biological reduction of CO{sub 2} to methane. Elegantly simple, CoM, so named for its role as a methyl carrier in all methanogenic archaea, is the smallest known organic cofactor. It was thought that this cofactor was used exclusively in methanogenesis until it was recently discovered that CoM is a key cofactor in the pathway of propylene metabolism in the gram-negative soil microorganism Xanthobacter autotrophicus Py2. A four-step pathway requiring CoM converts propylene and CO{sub 2} to acetoacetate, which feeds into central metabolism. In this process, CoM is used to activate and convert highly electrophilic epoxypropane, formed from propylene epoxidation, into a nucleophilic species that undergoes carboxylation. The unique properties of CoM provide a chemical handle for orienting compounds for site-specific redox chemistry and stereospecific catalysis. The three-dimensional structures of several of the enzymes in the pathway of propylene metabolism in defined states have been determined, providing significant insights into both the enzyme mechanisms and the role of CoM in this pathway. These studies provide the structural basis for understanding the efficacy of CoM as a handle to direct organic substrate transformations at the active sites of enzymes.

  1. Structural basis for the alteration of coenzyme specificity in a malate dehydrogenase mutant

    SciTech Connect

    Tomita, Takeo; Fushinobu, Shinya; Kuzuyama, Tomohisa; Nishiyama, Makoto . E-mail: umanis@mail.ecc.u-tokyo.ac.jp

    2006-08-25

    To elucidate the structural basis for the alteration of coenzyme specificity from NADH toward NADPH in a malate dehydrogenase mutant EX7 from Thermus flavus, we determined the crystal structures at 2.0 A resolution of EX7 complexed with NADPH and NADH, respectively. In the EX7-NADPH complex, Ser42 and Ser45 form hydrogen bonds with the 2'-phosphate group of the adenine ribose of NADPH, although the adenine moiety is not seen in the electron density map. In contrast, although Ser42 and Ser45 occupy a similar position in the EX7-NADH complex structure, both the adenine and adenine ribose moieties of NADH are missing in the map. These results and kinetic analysis of site-directed mutant enzymes indicate (1) that the preference of EX7 for NADPH over NADH is ascribed to the recognition of the 2'-phosphate group by two Ser and Arg44, and (2) that the adenine moiety of NADPH is not recognized in this mutant.

  2. Structural requirements for novel coenzyme-substrate derivatives to inhibit intracellular ornithine decarboxylase and cell proliferation.

    PubMed

    Wu, Fang; Gehring, Heinz

    2009-02-01

    Creating transition-state mimics has proven to be a powerful strategy in developing inhibitors to treat malignant diseases in several cases. In the present study, structurally diverse coenzyme-substrate derivatives mimicking this type for pyridoxal 5'-phosphate-dependent human ornithine decarboxylase (hODC), a potential anticancer target, were designed, synthesized, and tested to elucidate the structural requirements for optimal inhibition of intracellular ODC as well as of tumor cell proliferation. Of 23 conjugates, phosphopyridoxyl- and pyridoxyl-L-tryptophan methyl ester (pPTME, PTME) proved significantly more potent in suppression proliferation (IC(50) up to 25 microM) of glioma cells (LN229) than alpha-DL-difluoromethylornithine (DFMO), a medically used irreversible inhibitor of ODC. In agreement with molecular modeling predictions, the inhibitory action of pPTME and PTME toward intracellular ODC of LN229 cells exceeded that of the previous designed lead compound POB. The inhibitory active compounds feature hydrophobic side chain fragments and a kind of polyamine motif (-NH-(CH(X))(4)-NH-). In addition, they induce, as polyamine analogs often do, the activity of the polyamine catabolic enzymes polyamine oxidase and spermine/spermidine N(1)-acetyltransferase up to 250 and 780%, respectively. The dual-action mode of these compounds in LN229 cells affects the intracellular polyamine metabolism and might underlie the more favorable cell proliferation inhibition in comparison with DFMO.

  3. Strategies for regeneration of nicotinamide coenzymes emphasizing self-sufficient closed-loop recycling systems.

    PubMed

    Hummel, Werner; Gröger, Harald

    2014-12-10

    Biocatalytic reduction reactions depending on nicotinamide coenzymes require an additional reaction to regenerate the consumed cofactor. For preparative application the preferred method is the simultaneous coupling of an in situ regeneration reaction. There are different strategically advantageous routes to achieve this goal. The standard method uses a second enzyme and a second co-substrate, for example formate and formate dehydrogenase or glucose and glucose dehydrogenase. Alternatively, a second substrate is employed which is converted by the same enzyme used for the primary reaction. For example, alcohol dehydrogenase catalyzed reactions are often coupled with excess 2-propanol which is oxidized to acetone during the regeneration of NAD(P)H. A third method utilizes a reaction-internal sequence by the direct coupling of an oxidizing and a reducing enzyme reaction. Neither an additional substrate nor a further regenerating enzyme are required for the recycling reaction. This kind of "closed-loop" or "self-sufficient" redox process for cofactor regeneration has been used rarely so far. Its most intriguing advantage is that even redox reactions with unstable precursors can be realized provided that this compound is produced in situ by an opposite redox reaction. This elegant method is applicable in special cases only but increasing numbers of examples have been published during the last years.

  4. Preformed {beta}-amyloid fibrils are destabilized by coenzyme Q{sub 10} in vitro

    SciTech Connect

    Ono, Kenjiro; Hasegawa, Kazuhiro; Naiki, Hironobu; Yamada, Masahito . E-mail: m-yamada@med.kanazawa-u.ac.jp

    2005-04-29

    Inhibition of the formation of {beta}-amyloid fibrils (fA{beta}), as well as the destabilization of preformed fA{beta} in the CNS, would be attractive therapeutic targets for the treatment of Alzheimer's disease (AD). We reported previously that nordihydroguaiaretic acid (NDGA) and wine-related polyphenol, myricetin (Myr), inhibit fA{beta} formation from A{beta} and destabilize preformed fA{beta} in vitro. Using fluorescence spectroscopic analysis with thioflavin T and electron microscopic studies, we examined the effects of coenzyme Q{sub 10} (CoQ{sub 10}) on the formation, extension, and destabilization of fA{beta} at pH 7.5 at 37 deg C in vitro. We next compared the anti-amyloidogenic activities of CoQ{sub 10} with NDGA and Myr. CoQ{sub 10} dose-dependently inhibited fA{beta} formation from amyloid {beta}-peptide (A{beta}), as well as their extension. Moreover, it destabilized preformed fA{beta}s. The anti-amyloidogenic effects of CoQ{sub 10} were slightly weaker than those of NDGA and Myr. CoQ{sub 10} could be a key molecule for the development of therapeutics for AD.

  5. Feedback regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase in Saccharomyces cerevisiae.

    PubMed Central

    Dimster-Denk, D; Thorsness, M K; Rine, J

    1994-01-01

    In eukaryotic cells all isoprenoids are synthesized from a common precursor, mevalonate. The formation of mevalonate from 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) is catalyzed by HMG-CoA reductase and is the first committed step in isoprenoid biosynthesis. In mammalian cells, synthesis of HMG-CoA reductase is subject to feedback regulation at multiple molecular levels. We examined the state of feedback regulation of the synthesis of the HMG-CoA reductase isozyme encoded by the yeast gene HMG1 to examine the generality of this regulatory pattern. In yeast, synthesis of Hmg1p was subject to feedback regulation. This regulation of HMG-CoA reductase synthesis was independent of any change in the level of HMG1 mRNA. Furthermore, regulation of Hmg1p synthesis was keyed to the level of a nonsterol product of the mevalonate pathway. Manipulations of endogenous levels of several isoprenoid intermediates, either pharmacologically or genetically, suggested that mevalonate levels may control the synthesis of Hmg1p through effects on translation. Images PMID:7949422

  6. Purification of a novel coenzyme F420-dependent glucose-6-phosphate dehydrogenase from Mycobacterium smegmatis.

    PubMed Central

    Purwantini, E; Daniels, L

    1996-01-01

    A variety of Mycobacterium species contained the 5-deazaflavin coenzyme known as F420. Mycobacterium smegmatis was found to have a glucose-6-phosphate dehydrogenase that was dependent on F420 as an electron acceptor and which did not utilize NAD or NADP. The enzyme was purified by ammonium sulfate fractionation, phenyl-Sepharose column chromatography, F420-ether-linked aminohexyl-Sepharose 4B affinity chromatography, and quaternary aminoethyl-Sephadex column chromatography, and the sequence of the first 26 N-terminal amino acids has been determined. The response of enzyme activity to a range of pHs revealed a two-peak pattern, with maxima at pH 5.5 and 8.0. The apparent Km values for F420 and glucose-6-phosphate were, respectively, 0.004 and 1.6 mM. The apparent native and subunit molecular masses were 78,000 and approximately 40,000 Da, respectively. PMID:8631674

  7. NLRP3 Inflammasome Is Activated in Fibromyalgia: The Effect of Coenzyme Q10

    PubMed Central

    Alcocer-Gómez, Elísabet; Culic, Ognjen; Carrión, Angel M.; de Miguel, Manuel; Díaz-Parrado, Eduardo; Pérez-Villegas, Eva M.; Bullón, Pedro; Battino, Maurizio; Sánchez-Alcazar, José Antonio

    2014-01-01

    Abstract Aims: Fibromyalgia (FM) is a prevalent chronic pain syndrome characterized by generalized hyperalgesia associated with a wide spectrum of symptoms such as fatigue and joint stiffness. Diagnosis of FM is difficult due to the lack of reliable diagnostic biomarkers, while treatment is largely inadequate. We have investigated the role of coenzyme Q10 (CoQ10) deficiency and mitochondrial dysfunction in inflammasome activation in blood cells from FM patients, and in vitro and in vivo CoQ10 deficiency models. Results: Mitochondrial dysfunction was accompanied by increased protein expression of interleukin (IL)-1β, NLRP3 (NOD-like receptor family, pyrin domain containing 3) and caspase-1 activation, and an increase of serum levels of proinflammatory cytokines (IL-1β and IL-18). CoQ10 deficiency induced by p-aminobenzoate treatment in blood mononuclear cells and mice showed NLRP3 inflammasome activation with marked algesia. A placebo-controlled trial of CoQ10 in FM patients has shown a reduced NLRP3 inflammasome activation and IL-1β and IL-18 serum levels. Innovation: These results show an important role for the NLRP3 inflammasome in the pathogenesis of FM, and the capacity of CoQ10 in the control of inflammasome. Conclusion: These findings provide new insights into the pathogenesis of FM and suggest that NLRP3 inflammasome inhibition represents a new therapeutic intervention for the disease. Antioxid. Redox Signal. 20, 1169–1180. PMID:23886272

  8. Improved high-performance liquid chromatographic method for the determination of coenzyme Q10 in plasma.

    PubMed

    Grossi, G; Bargossi, A M; Fiorella, P L; Piazzi, S; Battino, M; Bianchi, G P

    1992-02-28

    Coenzyme (Co) Q10 was dissociated from lipoproteins in plasma by treatment with methanol and extraction with n-hexane. Subsequent clean-up on silica gel and C18 solid-phase extraction cartridges with complete recovery (99 +/- 1.2%) produced a clean extract. High-performance liquid chromatographic (HPLC) separation was performed on a C18 reversed-phase column. Three simple, rapid procedures are presented: HPLC with final UV (275 nm) detection, a microanalysis utilizing a three-electrode electrochemical detector and a microanalysis with column-switching HPLC and electrochemical detection. The methods correlate very well with classical ethanol-n-hexane extraction with UV detection. The identity and purity of the Co Q10 peak were investigated and the resulting methods were concluded to be suitable for total plasma Co Q10 determination. The average level in healthy subjects was 0.80 +/- 0.20 mg/l; the minimum detectable Co Q10 plasma level was 0.05 and 0.005 mg/l for UV and electrochemical detection, respectively. The methods were applied to many samples and the plasma Co Q10 reference values for healthy subjects, athletes, hyperthyroid, hypothyroid and hypercholesterolaemic patients are given.

  9. Influence of gel and powdered formulations of coenzyme Q10 on metabolic parameters in rats.

    PubMed

    Preuss, Harry G; Echard, Bobby; Bagchi, Debasis; Clouatre, Dallas; Perricone, Nicholas V

    2010-07-01

    The healthful benefits of two commercially available formulations of coenzyme Q10 (Co Q10), one in gel and the other in a powdered form, on a variety of metabolic parameters in Sprague-Dawley rats (SD) were compared to control. The principal metabolic parameters examined were systolic blood pressure (SBP), DNA fragmentation, and free radical formation in hepatic and renal tissues. Compared to control, the powdered formulation significantly decreased SBP in the normotensive SD, whereas both commercial formulations lowered hepatic and renal DNA fragmentation and free radical formation. The gel-formulation lowered hepatic DNA fragmentation more than the powdered-formulation. In conclusion, both gel- and powdered-formulations of Co Q10 significantly influenced the metabolic parameters assessed in a favorable fashion, with the powdered-formulation more effective on SBP and the gel-formulation more effective on overcoming hepatic DNA fragmentation. From the data, we conclude that the choice of the formulation containing Co Q10 to be used should be based on the desired healthful benefits.

  10. Effect of coenzyme Q10 on superoxide production in rats with reperfusion injuries.

    PubMed

    Yokoyama, K; Nakamura, K; Nakamura, K; Kimura, M; Nomoto, K; Itoman, M

    1999-03-01

    We examined the effect of coenzyme Q10 (Co Q10) on superoxide radical (O2-) production in a model of rat reperfusion injury. The chemiluminescence method using a derivative of luciferin was used to quantify O2- production by erythrocytes in the reperfused limb after a period of ischaemia. A total of 20 limbs from Lewis rats were preserved at 4 degrees C in Euro-Collins solution for 72 hours, and were grafted orthotopically to syngeneic rats by a microsurgical technique. In the treated group (n = 10), Co Q10 (10 mg/kg) was injected intraperitoneally into the recipients one hour before reperfusion. In the control group (n = 10), the same dose of solvent was given. To measure the extent of oxidative stress, heparinised blood from the treated and control recipients was collected before, and at 15, 30, and 60 minutes after reperfusion for the measurement of chemiluminescence. O2- production in the Co Q10-treated group was significantly lower than in the control group (p < 0.05). Although these findings suggest that Co Q10 scavenged O2- that was produced in the replanted limbs as a result of ischaemia-reperfusion injury, we should consider other possible mechanisms by which this agent may protect against ischaemia-induced reperfusion injury.

  11. Severe encephalopathy associated to pyruvate dehydrogenase mutations and unbalanced coenzyme Q10 content

    PubMed Central

    Asencio, Claudio; Rodríguez-Hernandez, María A; Briones, Paz; Montoya, Julio; Cortés, Ana; Emperador, Sonia; Gavilán, Angela; Ruiz-Pesini, Eduardo; Yubero, Dèlia; Montero, Raquel; Pineda, Mercedes; O'Callaghan, María M; Alcázar-Fabra, María; Salviati, Leonardo; Artuch, Rafael; Navas, Plácido

    2016-01-01

    Coenzyme Q10 (CoQ10) deficiency is associated to a variety of clinical phenotypes including neuromuscular and nephrotic disorders. We report two unrelated boys presenting encephalopathy, ataxia, and lactic acidosis, who died with necrotic lesions in different areas of brain. Levels of CoQ10 and complex II+III activity were increased in both skeletal muscle and fibroblasts, but it was a consequence of higher mitochondria mass measured as citrate synthase. In fibroblasts, oxygen consumption was also increased, whereas steady state ATP levels were decreased. Antioxidant enzymes such as NQO1 and MnSOD and mitochondrial marker VDAC were overexpressed. Mitochondria recycling markers Fis1 and mitofusin, and mtDNA regulatory Tfam were reduced. Exome sequencing showed mutations in PDHA1 in the first patient and in PDHB in the second. These genes encode subunits of pyruvate dehydrogenase complex (PDH) that could explain the compensatory increase of CoQ10 and a defect of mitochondrial homeostasis. These two cases describe, for the first time, a mitochondrial disease caused by PDH defects associated with unbalanced of both CoQ10 content and mitochondria homeostasis, which severely affects the brain. Both CoQ10 and mitochondria homeostasis appears as new markers for PDH associated mitochondrial disorders. PMID:26014431

  12. Severe encephalopathy associated to pyruvate dehydrogenase mutations and unbalanced coenzyme Q10 content.

    PubMed

    Asencio, Claudio; Rodríguez-Hernandez, María A; Briones, Paz; Montoya, Julio; Cortés, Ana; Emperador, Sonia; Gavilán, Angela; Ruiz-Pesini, Eduardo; Yubero, Dèlia; Montero, Raquel; Pineda, Mercedes; O'Callaghan, María M; Alcázar-Fabra, María; Salviati, Leonardo; Artuch, Rafael; Navas, Plácido

    2016-03-01

    Coenzyme Q10 (CoQ10) deficiency is associated to a variety of clinical phenotypes including neuromuscular and nephrotic disorders. We report two unrelated boys presenting encephalopathy, ataxia, and lactic acidosis, who died with necrotic lesions in different areas of brain. Levels of CoQ10 and complex II+III activity were increased in both skeletal muscle and fibroblasts, but it was a consequence of higher mitochondria mass measured as citrate synthase. In fibroblasts, oxygen consumption was also increased, whereas steady state ATP levels were decreased. Antioxidant enzymes such as NQO1 and MnSOD and mitochondrial marker VDAC were overexpressed. Mitochondria recycling markers Fis1 and mitofusin, and mtDNA regulatory Tfam were reduced. Exome sequencing showed mutations in PDHA1 in the first patient and in PDHB in the second. These genes encode subunits of pyruvate dehydrogenase complex (PDH) that could explain the compensatory increase of CoQ10 and a defect of mitochondrial homeostasis. These two cases describe, for the first time, a mitochondrial disease caused by PDH defects associated with unbalanced of both CoQ10 content and mitochondria homeostasis, which severely affects the brain. Both CoQ10 and mitochondria homeostasis appears as new markers for PDH associated mitochondrial disorders.

  13. 3-hydroxy 3-methylglutaryl coenzyme A reductase inhibition impairs muscle regeneration.

    PubMed

    Trapani, Laura; Segatto, Marco; La Rosa, Piergiorgio; Fanelli, Francesca; Moreno, Sandra; Marino, Maria; Pallottini, Valentina

    2012-06-01

    Skeletal muscle has the ability to regenerate new muscle fibers after injury. The process of new muscle formation requires that quiescent mononuclear muscle precursor cells (myoblasts) become activated, proliferate, differentiate, and fuse into multinucleated myotubes which, in turn, undergo further differentiation and mature to form functional muscle fibers. Previous data demonstrated the crucial role played by 3-hydroxy 3-methylglutaryl coenzyme A reductase (HMGR), the rate-limiting enzyme of cholesterol biosynthetic pathway, in fetal rat myoblast (L6) differentiation. This finding, along with epidemiological studies assessing the myotoxic effect of statins, HMGR inhibitors, allowed us to speculate that HMGR could be strongly involved in skeletal muscle repair. Thus, our research was aimed at evaluating such involvement: in vitro and in vivo experiments were performed on both mouse adult satellite cell derived myoblasts (SCDM) and mouse muscles injured with cardiotoxin. Results demonstrate that HMGR inhibition by the statin Simvastatin reduces SCDM fusion index, fast MHC protein levels by 60% and slow MHC by 40%. Most importantly, HMGR inhibition delays skeletal muscle regeneration in vivo. Thus, besides complaining of myopathies, patients given Simvastatin could also undergo an impairment in muscle repair.

  14. In Vivo Analysis of Folate Coenzymes and Their Compartmentation in Saccharomyces Cerevisiae

    PubMed Central

    McNeil, J. B.; Bognar, A. L.; Pearlman, R. E.

    1996-01-01

    In eukaryotes, enzymes responsible for the interconversion of one-carbon units exist in parallel in both mitochondria and the cytoplasm. Strains of Saccharomyces cerevisiae were constructed that possess combinations of gene disruptions at the SHM1 [mitochondrial serine hydroxymethyltransferase (SHMTm)], SHM2 [cytoplasmic SHMT (SHMTc)], MIS1 [mitochondrial C(1)-tetrahydrofolate synthase (C(1)-THFSm)], ADE3 [cytoplasmic C(1)-THF synthase (C(1)-THFSc)], GCV1 [glycine cleavage system (GCV) protein T], and the GLY1 (involved in glycine synthesis) loci. Analysis of the in vivo growth characteristics and phenotypes was used to determine the contribution to cytoplasmic nucleic acid and amino acid anabolism by the mitochondrial enzymes involved in the interconversion of folate coenzymes. The data indicate that mitochondria transport formate to the cytoplasmic compartment and mitochondrial synthesis of formate appears to rely primarily on SHMTm rather than the glycine cleavage system. The glycine cleavage system and SHMTm cooperate to specifically synthesize serine. With the inactivation of SHM1, however, the glycine cleavage system can make an observable contribution to the level of mitochondrial formate. Inactivation of SHM1, SHM2 and ADE3 is required to render yeast auxotrophic for TMP and methionine, suggesting that TMP synthesized in mitochondria may be available to the cytoplasmic compartment. PMID:8852837

  15. Targeting and topology in the membrane of plant 3-hydroxy-3-methylglutaryl coenzyme A reductase.

    PubMed Central

    Campos, N; Boronat, A

    1995-01-01

    The enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) catalyzes the synthesis of mevalonate. This is the first committed step of isoprenoid biosynthesis. A common feature of all known plant HMGR isoforms is the presence of two highly conserved hydrophobic sequences in the N-terminal quarter of the protein. Using an in vitro system, we showed that the two hydrophobic sequences of Arabidopsis HMGR1S function as internal signal sequences. Specific recognition of these sequences by the signal recognition particle mediates the targeting of the protein to microsomes derived from the endoplasmic reticulum. Arabidopsis HMGR is inserted into the microsomal membrane, and the two hydrophobic sequences become membrane-spanning segments. The N-terminal end and the C-terminal catalytic domain of Arabidopsis HMGR are positioned on the cytosolic side of the membrane, whereas only a short hydrophilic sequence is exposed to the lumen. Our results suggest that the plant HMGR isoforms known to date are primarily targeted to the endoplasmic reticulum and have the same topology in the membrane. This reinforces the hypothesis that mevalonate is synthesized only in the cytosol. The possibility that plant HMGRs might be located in different regions of the endomembrane system is discussed. PMID:8718626

  16. Excess coenzyme A reduces skeletal muscle performance and strength in mice overexpressing human PANK2.

    PubMed

    Corbin, Deborah R; Rehg, Jerold E; Shepherd, Danielle L; Stoilov, Peter; Percifield, Ryan J; Horner, Linda; Frase, Sharon; Zhang, Yong-Mei; Rock, Charles O; Hollander, John M; Jackowski, Suzanne; Leonardi, Roberta

    2017-02-03

    Coenzyme A (CoA) is a cofactor that is central to energy metabolism and CoA synthesis is controlled by the enzyme pantothenate kinase (PanK). A transgenic mouse strain expressing human PANK2 was derived to determine the physiological impact of PANK overexpression and elevated CoA levels. The Tg(PANK2) mice expressed high levels of the transgene in skeletal muscle and heart; however, CoA was substantially elevated only in skeletal muscle, possibly associated with the comparatively low endogenous levels of acetyl-CoA, a potent feedback inhibitor of PANK2. Tg(PANK2) mice were smaller, had less skeletal muscle mass and displayed significantly impaired exercise tolerance and grip strength. Skeletal myofibers were characterized by centralized nuclei and aberrant mitochondria. Both the content of fully assembled complex I of the electron transport chain and ATP levels were reduced, while markers of oxidative stress were elevated in Tg(PANK2) skeletal muscle. These abnormalities were not detected in the Tg(PANK2) heart muscle, with the exception of spotty loss of cristae organization in the mitochondria. The data demonstrate that excessively high CoA may be detrimental to skeletal muscle function.

  17. Interactions of acyl-coenzyme A with phosphatidylcholine bilayers and serum albumin

    SciTech Connect

    Boylan, J.G.; Hamilton, J.A. )

    1992-01-21

    Interactions of oleoyl- and octanoyl-coenzyme A (CoA) with phosphatidylcholine (PC) vesicles and bovine serum albumin (BSA) were investigated by NMR spectroscopy. Binding of acyl-CoA to small unilamellar PC vesicles and to BSA was detected by changes in {sup 13}C and {sup 31}P chemical shifts relative to the chemical shifts for aqueous acyl-CoA. PC vesicles remained intact with {le} 15 mol % oleoyl-CoA, while higher oleoyl-CoA proportions produced mixed micelles. In contrast, {sup 13}C spectra revealed rapid exchange (ms) of octanoyl-CoA between the aqueous phase and PC vesicles and a low affinity for the bilayer. Thus, the binding affinity of acyl-CoA for PC bilayers is dependent on the acyl chain length. Addition of ({sup 13}C)carboxyl-enriched oleic acid to oleoyl-CoA/BSA mixtures revealed simultaneous binding of oleic acid and oleoyl-CoA to BSA, with some perturbation of binding interactions. Thus, BSA contains multiple binding sites for oleoyl-CoA and can bind fatty acid and acyl-CoA simultaneously.

  18. Physical activity affects plasma coenzyme Q10 levels differently in young and old humans.

    PubMed

    Del Pozo-Cruz, Jesús; Rodríguez-Bies, Elisabet; Ballesteros-Simarro, Manuel; Navas-Enamorado, Ignacio; Tung, Bui Thanh; Navas, Plácido; López-Lluch, Guillermo

    2014-04-01

    Coenzyme Q (Q) is a key lipidic compound for cell bioenergetics and membrane antioxidant activities. It has been shown that also has a central role in the prevention of oxidation of plasma lipoproteins. Q has been associated with the prevention of cholesterol oxidation and several aging-related diseases. However, to date no clear data on the levels of plasma Q during aging are available. We have measured the levels of plasmatic Q10 and cholesterol in young and old individuals showing different degrees of physical activity. Our results indicate that plasma Q10 levels in old people are higher that the levels found in young people. Our analysis also indicates that there is no a relationship between the degree of physical activity and Q10 levels when the general population is studied. However, very interestingly, we have found a different tendency between Q10 levels and physical activity depending on the age of individuals. In young people, higher activity correlates with lower Q10 levels in plasma whereas in older adults this ratio changes and higher activity is related to higher plasma Q10 levels and higher Q10/Chol ratios. Higher Q10 levels in plasma are related to lower lipoperoxidation and oxidized LDL levels in elderly people. Our results highlight the importance of life habits in the analysis of Q10 in plasma and indicate that the practice of physical activity at old age can improve antioxidant capacity in plasma and help to prevent cardiovascular diseases.

  19. Preparation, characterization and in silico modeling of biodegradable nanoparticles containing cyclosporine A and coenzyme Q10

    NASA Astrophysics Data System (ADS)

    Ankola, D. D.; Durbin, E. W.; Buxton, G. A.; Schäfer, J.; Bakowsky, U.; Kumar, M. N. V. Ravi

    2010-02-01

    Combination therapy will soon become a reality, particularly for those patients requiring poly-therapy to treat co-existing disease states. This becomes all the more important with the increasing cost, time and complexity of the drug discovery process prompting one to look at new delivery systems to increase the efficacy, safety and patient compliance of existing drugs. Along this line, we attempted to design nano-scale systems for simultaneous encapsulation of cyclosporine A (CsA) and coenzyme Q10 (CoQ10) and model their encapsulation and release kinetics. The in vitro characterization of the co-encapsulated nanoparticles revealed that the surfactant nature, concentration, external phase volume, droplet size reduction method and drug loading concentration can all influence the overall performance of the nanoparticles. The semi-quantitative solubility study indicates the strong influence of CoQ10 on CsA entrapment which was thought to be due to an increase in the lipophilicity of the overall system. The in vitro dissolution profile indicates the influence of CoQ10 on CsA release (64%) to that of individual particles of CsA, where the release is faster and higher (86%) on 18th day. The attempts to model the encapsulation and release kinetics were successful, offering a possibility to use such models leading to high throughput screening of drugs and their nature, alone or in combination for a particular polymer, if chi-parameters are understood.

  20. Coenzyme Q10 can prolong C. elegans lifespan by lowering oxidative stress.

    PubMed

    Ishii, Naoaki; Senoo-Matsuda, Nanami; Miyake, Kohichiro; Yasuda, Kayo; Ishii, Takamasa; Hartman, Philip S; Furukawa, Satoru

    2004-01-01

    The mev-1 gene encodes cytochrome b, a large subunit of the Complex II enzyme succinate-CoQ oxidoreductase. The mev-1(kn1) mutants are hypersensitive to oxidative stress and age precociously, probably because of elevated superoxide anion production in mitochondria. Coenzyme Q (CoQ) is essential for the mitochondrial respiratory chain. Here, we show that CoQ(10) and Vitamin E extended the life span of wild-type Caenorhabditis elegans. Conversely, only CoQ(10) recovered the life shortening effects seen in mev-1. We also show that CoQ(10) but not Vitamin E reduced superoxide anion levels in wild type and mev-1. Another previously described phenotype of mev-1 animals is the presence of supernumerary apoptotic cells. We now demonstrate that CoQ(10) (but not Vitamin E) suppressed these supernumerary apoptoses. Collectively these data suggest that exogenously supplied CoQ(10) can play a significant anti-aging function. It may do so either by acting as an antioxidant to dismutate the free radical superoxide anion or by reducing the uncoupling of reactions during election transport that could otherwise result in superoxide anion production. The latter activity has not been ascribed to CoQ(10); however, it is known that conditions that uncouple electron transport reactions can lead to elevated superoxide anion production.

  1. A neonatal case of 3-hydroxy-3-methylglutaric-coenzyme A lyase deficiency

    PubMed Central

    2013-01-01

    3-hydroxy-3-methylglutaric aciduria (OMIM 246450) is a rare autosomal recessive inborn of metabolism due to the deficiency of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) lyase, an enzyme involved both in the ketogenic pathway and leucine catabolism. Acute decompensations present with lethargy, cianosis, hypotonia, vomiting and metabolic acidosis with hypoketotic hypoglycemia. We report the case of a 3 days male with sudden hypoglycemic crisis initially misdiagnosed as a sepsis. HMG-CoA lyase deficiency was achieved through acyl-carnitines profile (showing a typical increasing of 3-hydroxy-isovaleryl and 3-methylgluraryl carnitines) and urinary organic acids analysis (disclosing elevation of 3-hydroxy-3-methylglutaric, 3-methyl-glutaconic, 3-methylglutaric and 3-hydroxyisovaleric acids). This case underlines the need of suspecting such inborn metabolic disorder in cases with hypoglycemia and metabolic acidosis. Acyl-carnitine and urinary organic acids profiles are essential to achieve a prompt diagnosis of treatable metabolic disorders in order to prevent their acute crisis with serious or even fatal consequences. PMID:23705938

  2. Lipid accumulation, lipid body formation, and acyl coenzyme A oxidases of the yeast Yarrowia lipolytica.

    PubMed

    Mlícková, Katerina; Roux, Emeline; Athenstaedt, Karin; d'Andrea, Sabine; Daum, Günther; Chardot, Thierry; Nicaud, Jean-Marc

    2004-07-01

    Yarrowia lipolytica contains five acyl-coenzyme A oxidases (Aox), encoded by the POX1 to POX5 genes, that catalyze the limiting step of peroxisomal beta-oxidation. In this study, we analyzed morphological changes of Y. lipolytica growing in an oleic acid medium and the effect of POX deletions on lipid accumulation. Protrusions involved in the uptake of lipid droplets (LDs) from the medium were seen in electron micrographs of the surfaces of wild-type cells grown on oleic acid. The number of protrusions and surface-bound LDs increased during growth, but the sizes of the LDs decreased. The sizes of intracellular lipid bodies (LBs) and their composition depended on the POX genotype. Only a few, small, intracellular LBs were observed in the mutant expressing only Aox4p (Deltapox2 Deltapox3 Deltapox5), but strains expressing either Aox3p or both Aox3p and Aox4p had the same number of LBs as did the wild type. In contrast, strains expressing either Aox2p or both Aox2p and Aox4p formed fewer, but larger, LBs than did the wild type. The size of the LBs increased proportionately with the amount of triacylglycerols in the LBs of the mutants. In summary, Aox2p expression regulates the size of cellular triacylglycerol pools and the size and number of LBs in which these fatty acids accumulate.

  3. Benzoyl-coenzyme A thioesterase of Azoarcus evansii: properties and function.

    PubMed

    Ismail, Wael

    2008-10-01

    The aerobic benzoate metabolism in Azoarcus evansii follows an unusual route. The intermediates of the pathway are processed as coenzyme A (CoA) thioesters and the cleavage of the aromatic ring is non-oxygenolytic. The enzymes of this pathway are encoded by the box gene cluster which harbors a gene, orf1, coding for a putative thioesterase. Benzoyl-CoA thioesterase activity (20 nmol min(-1) mg(-1) protein) was present in cells grown aerobically on benzoate, but was lacking in cells grown on other aromatic or aliphatic substrates under oxic or anoxic conditions. The gene was cloned and overexpressed in Escherichia coli to produce a C-terminal His-tag fusion protein. The recombinant enzyme was a homotetramer of 16 kDa subunits. It catalyzed not only the hydrolysis of benzoyl-CoA, but also of 2,3-dihydro-2,3-dihydroxybenzoyl-CoA, the second intermediate in the pathway. The enzyme exhibited higher activity with mono-substituted derivatives of benzoyl-CoA, showing highest activity with 4-hydroxybenzoyl-CoA. Di-substituted derivatives of benzoyl-CoA, phenylacetyl-CoA, and aliphatic CoA thioesters were not hydrolyzed but some acted as inhibitors. The thioesterase appears to protect the cell from CoA pool depletion. It may constitute the prototype of a new subfamily within the hotdog fold enzyme superfamily.

  4. Coenzyme Q10 Abrogated the 28 Days Aluminium Chloride Induced Oxidative Changes in Rat Cerebral Cortex

    PubMed Central

    Majumdar, Anuradha S.; Nirwane, Abhijit; Kamble, Rahul

    2014-01-01

    Objective: The present study was designed to elucidate the impact of oral administration of aluminium chloride for 28 days with respect to oxidative stress in the cerebral cortex of female rats. Further, to investigate the potentials of Coenzyme (Co) Q10 (4, 8, and 12 mg/kg, i.p.) in mitigating the detrimental changes. Materials and Methods: Biochemical estimations of cerebral lipid peroxidation (LPO), reduced glutathione (GSH), vitamin E and activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were carried out after 28 days of aluminium chloride (AlCl3) and Co Q10 exposures along with histopathological examination of cerebral cortex of the rats. Results: Subacute exposure to AlCl3(5 mg/kg) led to significant decrease in levels of GSH, vitamin E and activities of SOD, CAT, GPx, and an increase in LPO of cerebral cortex. These aberrations were restored by Co Q10 (12 mg/kg, i.p.). This protection offered was comparable to that of L-deprenyl (1 mg/kg, i.p.) which served as a reference standard. Histopathological evaluations confirmed that the normal cerebral morphology was maintained by Co Q10. Conclusion: Thus, AlCl3 exposure hampers the activities of various antioxidant enzymes and induces oxidative stress in cerebral cortex of female Wistar rats. Supplementation with intraperitoneal Co Q10 abrogated these deleterious effects of AlCl3. PMID:25253934

  5. Plasma and hepatic carnitine and coenzyme A pools in a patient with fatal, valproate induced hepatotoxicity.

    PubMed Central

    Krähenbühl, S; Mang, G; Kupferschmidt, H; Meier, P J; Krause, M

    1995-01-01

    Reduced hepatic mitochondrial beta-oxidation and changes in the plasma carnitine pool are important biochemical findings in valproate induced liver toxicity. The carnitine pools in plasma and liver and the liver coenzyme A (CoA) pool in a patient with fatal, valproate induced hepatotoxicity were measured. In plasma and liver the free and total carnitine contents were decreased, whereas the ratios short chain acylcarnitine/total acid soluble carnitine were increased. The long chain acylcarnitine content was unchanged in plasma, and increased in liver. The total CoA content in liver was decreased by 84%. This was due to reduced concentrations of CoASH, acetyl-CoA, and long chain acyl-CoA whereas the concentrations of succinyl-CoA and propionyl-CoA were both increased. The good agreement between the plasma and liver carnitine pools reflects the close relation between these two pools. The observed decrease in the hepatic CoASH and total CoA content has so far not been reported in humans with valproate induced hepatotoxicity and may be functionally significant. PMID:7672665

  6. ANO10 mutations cause ataxia and coenzyme Q₁₀ deficiency.

    PubMed

    Balreira, Andrea; Boczonadi, Veronika; Barca, Emanuele; Pyle, Angela; Bansagi, Boglarka; Appleton, Marie; Graham, Claire; Hargreaves, Iain P; Rasic, Vedrana Milic; Lochmüller, Hanns; Griffin, Helen; Taylor, Robert W; Naini, Ali; Chinnery, Patrick F; Hirano, Michio; Quinzii, Catarina M; Horvath, Rita

    2014-11-01

    Inherited ataxias are heterogeneous disorders affecting both children and adults, with over 40 different causative genes, making molecular genetic diagnosis challenging. Although recent advances in next-generation sequencing have significantly improved mutation detection, few treatments exist for patients with inherited ataxia. In two patients with adult-onset cerebellar ataxia and coenzyme Q10 (CoQ10) deficiency in muscle, whole exome sequencing revealed mutations in ANO10, which encodes anoctamin 10, a member of a family of putative calcium-activated chloride channels, and the causative gene for autosomal recessive spinocerebellar ataxia-10 (SCAR10). Both patients presented with slowly progressive ataxia and dysarthria leading to severe disability in the sixth decade. Epilepsy and learning difficulties were also present in one patient, while retinal degeneration and cataract were present in the other. The detection of mutations in ANO10 in our patients indicate that ANO10 defects cause secondary low CoQ10 and SCAR10 patients may benefit from CoQ10 supplementation.

  7. Application of coenzyme Q10 for accelerating soft tissue wound healing after tooth extraction in rats.

    PubMed

    Yoneda, Toshiki; Tomofuji, Takaaki; Kawabata, Yuya; Ekuni, Daisuke; Azuma, Tetsuji; Kataoka, Kota; Kunitomo, Muneyoshi; Morita, Manabu

    2014-12-10

    Accelerating wound healing after tooth extraction is beneficial in dental treatment. Application of antioxidants, such as reduced coenzyme Q10 (rCoQ10), may promote wound healing after tooth extraction. In this study, we examined the effects of topical application of rCoQ10 on wound healing after tooth extraction in rats. After maxillary first molars were extracted, male Fischer 344 rats (8 weeks old) (n = 27) received topical application of ointment containing 5% rCoQ10 (experimental group) or control ointment (control group) to the sockets for 3 or 8 days (n = 6-7/group). At 3 days after extraction, the experimental group showed higher collagen density and lower numbers of polymorphonuclear leukocytes in the upper part of socket, as compared to the control group (p < 0.05). Gene expression of interleukin-1β, tumor necrosis factor-α and nuclear factor-κB were also lower in the experimental group than in the control group (p < 0.05). At 8 days after tooth extraction, there were no significant differences in collagen density, number of polymorphonuclear leukocytes and bone fill between the groups. Our results suggest that topical application of rCoQ10 promotes wound healing in the soft tissue of the alveolar socket, but that rCoQ10 has a limited effect on bone remodeling in rats.

  8. Water-Soluble Coenzyme Q10 Reduces Rotenone-Induced Mitochondrial Fission.

    PubMed

    Li, Hai-Ning; Zimmerman, Mary; Milledge, Gaolin Z; Hou, Xiao-Lin; Cheng, Jiang; Wang, Zhen-Hai; Li, P Andy

    2017-02-11

    Parkinson's disease is a neurodegenerative disorder characterized by mitochondrial dysfunction and oxidative stress. It is usually accompanied by an imbalance in mitochondrial dynamics and changes in mitochondrial morphology that are associated with impaired function. The objectives of this study were to identify the effects of rotenone, a drug known to mimic the pathophysiology of Parkinson's disease, on mitochondrial dynamics. Additionally, this study explored the protective effects of water-soluble Coenzyme Q10 (CoQ10) against rotenone-induced cytotoxicity in murine neuronal HT22 cells. Our results demonstrate that rotenone elevates protein expression of mitochondrial fission markers, Drp1 and Fis1, and causes an increase in mitochondrial fragmentation as evidenced through mitochondrial staining and morphological analysis. Water-soluble CoQ10 prevented mitochondrial dynamic imbalance by reducing Drp1 and Fis1 protein expression to pre-rotenone levels, as well as reducing rotenone treatment-associated mitochondrial fragmentation. Hence, water-soluble CoQ10 may have therapeutic potential in treating patients with Parkinson's disease.

  9. CoenzymeQ10 localizations in model membranes. A Langmuir monolayer study.

    PubMed

    Nerdal, Willy; Nilsen, Torill Regine Sandvik; Steinkopf, Signe

    2015-12-01

    The interaction of coenzyme Q10 (CoQ10) in a monolayer of 1,2-dipalmitoyl-sn-glysero-3-phospho-L-choline (DPPC), in a monolayer of 1,2-dierucoyl-sn-glysero-3-phospho-L-choline (DEPC), in a monolayer of 1-palmitoyl-2-oleoyl-sn-glysero-3-phospho-L-serine (POPS) and in a monolayer of total lipid extract from pig brain (PB) has been investigated by using the Langmuir monolayer technique. Surface pressure (π)-mean molecular area (mma) isotherms have been measured for pure lipid monolayers and lipid monolayers with 0.5, 1.0, 2.0, 5.0 and 10.0 mol% CoQ10 concentrations. At the biological concentration (1.0-3.0 mol%) of CoQ10, intercalation of CoQ10 occurs in the lipid acyl chains of DPPC, POPS and PB monolayers. Above the biological concentration of CoQ10, the CoQ10 molecule induces domain formation in the monolayers of DPPC, POPS and PB lipids. The DEPC monolayer behavior deviates from the other lipids in this study. At 2.0 mol% the CoQ10 promotes very dense lipid packing, and the CoQ10 molecule is located parallel to the DEPC acyl chains at all concentrations.

  10. Regulation of Stearoyl Coenzyme A Desaturase 1 Gene Promoter in Bovine Mammary Cells.

    PubMed

    di Martino, O; Troiano, A; Addi, L; Guarino, A; Calabrò, S; Tudisco, R; Murru, N; Cutrignelli, M I; Infascelli, F; Calabrò, V

    2015-01-01

    Stearoyl-Coenzyme A desaturase 1 (SCD1) belongs to the fatty acid family of desaturases. In lactating ruminants, the SCD1 protein is highly expressed in the mammary gland and is relevant for the fatty acid composition of milk and dairy products. Bovine mammary epithelial cells (BME-UV1), cultured in vitro, have been proposed as a model to reproduce the biology of the mammary gland. The present study was designed to investigate the responsiveness of bovine SCD1 promoter to serum, insulin, oleic acid, and NFY transcription factor in BME-UV1 cells. A luciferase-based reporter assay was used to monitor the transcriptional activity of the SCD1 promoter region in BME-UV1 cells treated or not with insulin and/or oleic acid. The level of endogenous SCD1 mRNA was evaluated by Real time PCR. Insulin (20 ng/mL) induced a 2.0 to 2.5-fold increase of SCD1 promoter activity. Additionally, the effect of insulin was inhibited by oleic acid, serum components, and NFY enforced expression. Serum and NFY showed no synergistic or additive effect on SCD1 promoter activity suggesting that they repress SCD1 transcription through the same responsive element.

  11. 3-Methylglutaconyl-Coenzyme-A Hydratase Deficiency and the Development of Dilated Cardiomyopathy

    PubMed Central

    Spergel, Craig D.; Milko, Mariya; Edwards, Christopher; Steinhoff, Jeff P.

    2014-01-01

    A 25-year-old Canadian male with a history of 3-methylglutaconyl-coenzyme-A hydratase deficiency, also known as 3-methylglutaconic aciduria type I, a very rare inborn error of metabolism, presented with respiratory distress, nausea, vomiting and signs of multisystem organ failure due to a suspected underlying infectious process. An electrocardiogram revealed bilateral atrial enlargement and an elevated brain natriuretic peptide on the initial laboratory studies, which prompted a more thorough cardiac workup. The transthoracic echocardiogram revealed a dilated cardiomyopathy with severe systolic dysfunction. The deficient enzyme present in this patient is involved in the pathway of leucine catabolism and is particularly important in various tissues for energy production and sterol synthesis. The dilated cardiomyopathy in this patient possibly had a variety of potential mechanisms including: a mitochondrial myopathy due to the deficiency of this enzyme leading to a defect in energy production inside cardiac myocytes; or a direct toxicity from 3-methylglutaconic acid (3-MGA) and its toxic metabolites; or a cardiac dysfunction due to a variety of other potential mechanisms. In conclusion, this patient’s clinical presentation suggested that 3-methylglutaconyl-CoA hydratase deficiency could cause a severe dilated cardiomyopathy and heart failure. PMID:28348715

  12. Rapid determination of coenzyme Q10 in food supplements using 1H NMR spectroscopy.

    PubMed

    Monakhova, Yulia B; Ruge, Ingrid; Kuballa, Thomas; Lerch, Christiane; Lachenmeier, Dirk W

    2013-01-01

    A methodology utilizing 1H NMR spectroscopy has been developed to measure the concentration of coenzyme Q10 (CoQ10) in dietary supplements. For sample preparation, a very simple dilution with deuterated chloroform and addition of internal standard is sufficient. CoQ10 produces a distinct peak of the CH groups in the isoprene side chain of the molecule in the δ 5.15 - 5.05 ppm range, where it can be distinguished from other matrix compounds. The method was shown to be of adequate sensitivity with a limit of detection (LOD) of 7.8 mg/L, to control the CoQ10 content in the majority of the products. The precision expressed as relative standard deviation was around 5 %; linearity was observed from 14 to 2000 mg/L (R = 0.99). The developed methodology was applied for the analysis of 21 food supplements (capsules, tablets, and liquid products). On the basis of the labeled amounts, only two products contained substantially lower concentrations of CoQ10 (57 % and 51 %). All other concentrations varied between 83 % and 190 % with respect to labeling. The developed NMR method may be used by quality assurance laboratories for routine control of CoQ10 products.

  13. Dependence of Brown Adipose Tissue Function on CD36-Mediated Coenzyme Q Uptake

    PubMed Central

    Anderson, Courtney M.; Kazantzis, Melissa; Wang, Jinshan; Venkatraman, Subramaniam; Goncalves, Renata L. S.; Quinlan, Casey L.; Ng, Ryan; Jastroch, Martin; Benjamin, Daniel I.; Nie, Biao; Herber, Candice; Ngoc Van, An-Angela; Park, Michael J.; Yun, Dawee; Chan, Karen; Yu, Angela; Vuong, Peter; Febbraio, Maria; Nomura, Daniel; Napoli, Joseph; Brand, Martin D.; Stahl, Andreas

    2014-01-01

    Summary Brown adipose tissue (BAT) possesses the inherent ability to dissipate metabolic energy as heat through uncoupled mitochondrial respiration. An essential component of the mitochondrial electron transport chain is coenzyme Q (CoQ). While cells mostly synthesize CoQ endogenously, exogenous supplementation with CoQ has been successful as a therapy for patients with CoQ deficiency. However, which tissues depend on exogenous CoQ uptake as well as the mechanism by which CoQ is taken up by cells and the role of this process in BAT function is not well understood. Here we report that the scavenger receptor CD36 drives the uptake of CoQ by BAT and is required for normal BAT function. BAT from mice lacking CD36 displays CoQ deficiency, impaired CoQ uptake, hypertrophy, altered lipid metabolism, mitochondrial dysfunction, and defective non-shivering thermogenesis. Together, these data reveal an important new role for the systemic transport of CoQ to BAT and its function in thermogenesis. PMID:25620701

  14. High resolution neutron crystallographic studies of the hydration of coenzyme cob(II)alamin

    SciTech Connect

    Jogl, Gerwald; Wang, Xiaoping; Mason, Sax; Kovalevsky, Andrey; Mustyakimov, Marat; Fisher, Zoe; Hoffmann, Christina; Kratky, Christoph; Langan, Paul

    2011-01-01

    The hydration of coenzyme cob(II)alamin has been studied using high resolution monochromatic neutron crystallographic data collected at room temperature to a resolution of surrounded by flexible side chains with terminal functional groups may be significant for 0.92 on the original diffractometer D19 with a prototype 4o x 64o detector at the high-flux reactor neutron source run by the Institute Laue Langevin. The resulting structure provides H bonding parameters for the hydration of biomacromolecules to unprecedented accuracy. These experimental parameters will be used to define more accurate force-fields for biomacromolecular structure refinement. The presence of a hydrophobic bowl motif efficient scavenging of ligands. The feasibility of extending the resolution of this structure to ultra high resolution was investigated by collecting time-of-flight neutron crystallographic data on diffractometer TOPAZ with a prototype array of 14 modular 21o x 21o detectors at the Spallation Neutron Source run by Oak Ridge National Laboratory.

  15. Coenzyme Q and Its Role in the Dietary Therapy against Aging.

    PubMed

    Varela-López, Alfonso; Giampieri, Francesca; Battino, Maurizio; Quiles, José L

    2016-03-18

    Coenzyme Q (CoQ) is a naturally occurring molecule located in the hydrophobic domain of the phospholipid bilayer of all biological membranes. Shortly after being discovered, it was recognized as an essential electron transport chain component in mitochondria where it is particularly abundant. Since then, more additional roles in cell physiology have been reported, including antioxidant, signaling, death prevention, and others. It is known that all cells are able to synthesize functionally sufficient amounts of CoQ under normal physiological conditions. However, CoQ is a molecule found in different dietary sources, which can be taken up and incorporated into biological membranes. It is known that mitochondria have a close relationship with the aging process. Additionally, delaying the aging process through diet has aroused the interest of scientists for many years. These observations have stimulated investigation of the anti-aging potential of CoQ and its possible use in dietary therapies to alleviate the effects of aging. In this context, the present review focus on the current knowledge and evidence the roles of CoQ cells, its relationship with aging, and possible implications of dietary CoQ in relation to aging, lifespan or age-related diseases.

  16. Rv0132c of Mycobacterium tuberculosis Encodes a Coenzyme F420-Dependent Hydroxymycolic Acid Dehydrogenase

    PubMed Central

    Purwantini, Endang; Mukhopadhyay, Biswarup

    2013-01-01

    The ability of Mycobacterium tuberculosis to manipulate and evade human immune system is in part due to its extraordinarily complex cell wall. One of the key components of this cell wall is a family of lipids called mycolic acids. Oxygenation of mycolic acids generating methoxy- and ketomycolic acids enhances the pathogenic attributes of M. tuberculosis. Thus, the respective enzymes are of interest in the research on mycobacteria. The generation of methoxy- and ketomycolic acids proceeds through intermediary formation of hydroxymycolic acids. While the methyl transferase that generates methoxymycolic acids from hydroxymycolic acids is known, hydroxymycolic acids dehydrogenase that oxidizes hydroxymycolic acids to ketomycolic acids has been elusive. We found that hydroxymycolic acid dehydrogenase is encoded by the rv0132c gene and the enzyme utilizes F420, a deazaflavin coenzyme, as electron carrier, and accordingly we called it F420-dependent hydroxymycolic acid dehydrogenase. This is the first report on the involvement of F420 in the synthesis of a mycobacterial cell envelope. Also, F420-dependent hydroxymycolic acid dehydrogenase was inhibited by PA-824, and therefore, it is a previously unknown target for this new tuberculosis drug. PMID:24349169

  17. Nano-encapsulation of coenzyme Q10 using octenyl succinic anhydride modified starch.

    PubMed

    Cheuk, Sherwin Y; Shih, Frederick F; Champagne, Elaine T; Daigle, Kim W; Patindol, James A; Mattison, Christopher P; Boue, Stephen M

    2015-05-01

    Octenyl succinic anhydride modified starch (OSA-ST) was used to encapsulate coenzyme Q10 (CoQ10). CoQ10 was dissolved in rice bran oil and incorporated into an aqueous OSA-ST solution. High pressure homogenisation of the mixture was conducted at 170 MPa for 56 cycles. The resulting emulsion had a particle size range of 200-300 nm and the absolute zeta potential varied between 8.4 and 10.6 mV. CoQ10 retention of the emulsion and freeze dried products, determined by a hexane rinse, was 98.2%. Reconstitution of the freeze dried product in Mcllvaine citrate-phosphate buffers with pH values of 3-5 and temperatures at 4 and 25 °C had very little effect on the range and distribution of the nanoparticles' size. The inflection point of the zeta potential and pH plot occurred at the first pKa of succinic acid (pH 4.2), indicating succinate as the main influence over zeta potential.

  18. CINRG Pilot trial of Coenzyme Q10 in steroid treated Duchenne Muscular Dystrophy

    PubMed Central

    Spurney, Christopher F.; Rocha, Carolina Tesi; Henricson, Erik; Florence, Julaine; Mayhew, Jill; Gorni, Ksenija; Pasquali, Livia; Pestronk, Alan; Martin, Gerard R.; Hu, Fengming; Nie, Lei; Connolly, Anne M.; Escolar, Diana M.

    2011-01-01

    Introduction Corticosteroid treatment slows disease progression and is the standard of care for Duchenne muscular dystrophy (DMD). Coenzyme Q10 (CoQ10) is a potent antioxidant that may improve function in dystrophin deficient muscle. Methods We performed an open label, “add-on” pilot study of CoQ10 in thirteen 5–10 year old DMD patients on steroids. The primary outcome measure was the total Quantitative Muscle Testing (QMT) score. Results Twelve of 16 children (mean age 8.03±1.64 years) completed the trial. Target serum levels of CoQ10 (≥2.5 μg/ml) were shown to be subject- and administration-dependent. Nine of 12 subjects showed an increase in total QMT score. Overall, CoQ10 treatment resulted in 8.5 % increase in muscle strength (p=0.03). Discussion This pilot study found the addition of CoQ10 to prednisone therapy in DMD patients resulted in an increase in muscle strength. These results warrant a larger, controlled trial of CoQ10 in DMD. PMID:21698649

  19. Investigation of Pyridine Carboxylic Acids in CM2 Carbonaceous Chondrites: Potential Precursor Molecules for Ancient Coenzymes

    NASA Technical Reports Server (NTRS)

    Smith, Karen E.; Callahan, Michael P.; Gerakines, Perry A.; Dworkin, Jason P.; House, Christopher H.

    2014-01-01

    The distribution and abundances of pyridine carboxylic acids (including nicotinic acid) in eight CM2 carbonaceous chondrites (ALH 85013, DOM 03183, DOM 08003, EET 96016, LAP 02333, LAP 02336, LEW 85311, and WIS 91600) were investigated by liquid chromatography coupled to UV detection and high resolution Orbitrap mass spectrometry. We find that pyridine monocarboxylic acids are prevalent in CM2-type chondrites and their abundance negatively correlates with the degree of pre-terrestrial aqueous alteration that the meteorite parent body experienced. We also report the first detection of pyridine dicarboxylic acids in carbonaceous chondrites. Additionally, we carried out laboratory studies of proton-irradiated pyridine in carbon dioxide-rich ices (a 1:1 mixture) to serve as a model of the interstellar ice chemistry that may have led to the synthesis of pyridine carboxylic acids. Analysis of the irradiated ice residue shows that a comparable suite of pyridine mono- and dicarboxylic acids was produced, although aqueous alteration may still play a role in the synthesis (and ultimate yield) of these compounds in carbonaceous meteorites. Nicotinic acid is a precursor to nicotinamide adenine dinucleotide, a likely ancient molecule used in cellular metabolism in all of life, and its common occurrence in CM2 chondrites may indicate that meteorites may have been a source of molecules for the emergence of more complex coenzymes on the early Earth.

  20. Investigation of Pyridine Carboxylic Acids in CM2 Carbonaceous Chondrites: Potential Precursor Molecules for Ancient Coenzymes

    NASA Technical Reports Server (NTRS)

    Smith, Karen E.; Callahan, Michael P.; Gerakines, Perry A.; Dworkin, Jason P.; House, Christopher H.

    2014-01-01

    The distribution and abundances of pyridine carboxylic acids (including nicotinic acid) in eight CM2 carbonaceous chondrites (ALH 85013, DOM 03183, DOM 08003, EET 96016, LAP 02333, LAP 02336, LEW 85311, and WIS 91600) were investigated by liquid chromatography coupled to UV detection and high resolution Orbitrap mass spectrometry. We find that pyridine monocarboxylic acids are prevalent in CM2-type chondrites and their abundance negatively correlates with the degree of pre-terrestrial aqueous alteration that the meteorite parent body experienced. We lso report the first detection of pyridine dicarboxylic acids in carbonaceous chondrites. Additionally, we carried out laboratory studies of proton-irradiated pyridine in carbon dioxide-rich ices (a 1:1 mixture) to serve as a model of the interstellar ice chemistry that may have led to the synthesis of pyridine carboxylic acids. Analysis of the irradiated ice residue shows that a comparable suite of pyridine mono- and dicarboxylic acids was produced, although aqueous alteration may still play a role in the synthesis (and ultimate yield) of these compounds in carbonaceous meteorites. Nicotinic acid is a precursor to nicotinamide adenine dinucleotide, a likely ancient molecule used in cellular metabolism in all of life, and its common occurrence in CM2 chondrites may indicate that meteorites may have been a source of molecules for the emergence of more complex coenzymes on the early Earth.

  1. Essential Role of Caffeoyl Coenzyme A O-Methyltransferase in Lignin Biosynthesis in Woody Poplar Plants

    PubMed Central

    Zhong, Ruiqin; Morrison, W. Herbert; Himmelsbach, David S.; Poole, Farris L.; Ye, Zheng-Hua

    2000-01-01

    Caffeoyl coenzyme A O-methyltransferase (CCoAOMT) has recently been shown to participate in lignin biosynthesis in herbacious tobacco plants. Here, we demonstrate that CCoAOMT is essential in lignin biosynthesis in woody poplar (Populus tremula × Populus alba) plants. In poplar stems, CCoAOMT was found to be expressed in all lignifying cells including vessel elements and fibers as well as in xylem ray parenchyma cells. Repression of CCoAOMT expression by the antisense approach in transgenic poplar plants caused a significant decrease in total lignin content as detected by both Klason lignin assay and Fourier-transform infrared spectroscopy. The reduction in lignin content was the result of a decrease in both guaiacyl and syringyl lignins as determined by in-source pyrolysis mass spectrometry. Fourier-transform infrared spectroscopy indicated that the reduction in lignin content resulted in a less condensed and less cross-linked lignin structure in wood. Repression of CCoAOMT expression also led to coloration of wood and an elevation of wall-bound p-hydroxybenzoic acid. Taken together, these results indicate that CCoAOMT plays a dominant role in the methylation of the 3-hydroxyl group of caffeoyl CoA, and the CCoAOMT-mediated methylation reaction is essential to channel substrates for 5-methoxylation of hydroxycinnamates. They also suggest that antisense repression of CCoAOMT is an efficient means for genetic engineering of trees with low lignin content. PMID:11027707

  2. Statins restore ischemic limb blood flow in diabetic microangiopathy via eNOS/NO upregulation but not via PDGF-BB expression.

    PubMed

    Fujii, Takaaki; Onimaru, Mitsuho; Yonemitsu, Yoshikazu; Kuwano, Hiroyuki; Sueishi, Katsuo

    2008-06-01

    3-Hydroxy-3-methyl-glutaryl CoA reductase inhibitors, or statins, have pleiotropic effects and can protect the vasculature in a manner independent of their lipid-lowering effect. The effectiveness of statins in reducing the risk of coronary events has been shown even in patients with diabetes, and their effects on diabetic complications have been reported. Using a model of severe hindlimb ischemia in streptozotocin-induced diabetic mice (STZ-DM), we investigated the effects and mechanisms of statin therapy in diabetic angiopathy in ischemic hindlimbs. As a result, STZ-DM mice frequently lost their hindlimbs after induced ischemia, whereas non-DM mice did not. Supplementation with statins significantly prevented autoamputation. We previously showed that diabetic vascular complications are caused by impaired expression of PDGF-BB, but statin therapy did not enhance PDGF-BB expression. Statins helped enhance endogenous endothelial nitric oxide (NO) synthase (eNOS) expression. Furthermore, the inhibition of NO synthesis by the administration of N(omega)-nitro-l-arginine methyl ester impaired the ability of statins to prevent STZ-DM mouse limb autoamputation, indicating that the therapeutic effect of statins in hindlimb ischemia in STZ-DM mice occurs via the eNOS/NO pathway. A combination therapy of statins and PDGF-BB gene supplementation was more effective for diabetic angiopathy than either therapy alone. In conclusion, these findings indicate that statin therapy might be useful for preventing intractable diabetic foot disease in patients with diabetic angiopathy.

  3. Inhibition of in vitro cholesterol synthesis by fatty acids.

    PubMed

    Kuroda, M; Endo, A

    1976-01-18

    Inhibitory effect of 44 species of fatty acids on cholesterol synthesis has been examined with a rat liver enzyme system. In the case of saturated fatty acids, the inhibitory activity increased with chain length to a maximum at 11 to 14 carbons, after which activity decreased rapidly. The inhibition increased with the degree of unsaturation of fatty acids. Introduction of a hydroxy group at the alpha-position of fatty acids abolished the inhibition, while the inhibition was enhanced by the presence of a hydroxy group located in an intermediate position of the chain. Branched chain fatty acids having a methyl group at the terminal showed much higher activity than the corresponding saturated straight chain fatty acids with the same number of carbons. With respect to the mechanism for inhibition, tridecanoate was found to inhibit acetoacetyl-CoA thiolase specifically without affecting the other reaction steps in the cholesterol synthetic pathway. The highly unsaturated fatty acids, arachidonate and linoleate, were specific inhibitors of 3-hydroxy-3-methyl-glutaryl-CoA synthase. On the other hand, ricinoleate (hydroxy acid) and phytanate (branched-chain acid) diminished the conversion of mevalonate to sterols by inhibiting a step or steps between squalene and lanosterol.

  4. Therapeutic modification of arterial stiffness: An update and comprehensive review

    PubMed Central

    Wu, Ching-Fen; Liu, Pang-Yen; Wu, Tsung-Jui; Hung, Yuan; Yang, Shih-Ping; Lin, Gen-Min

    2015-01-01

    Arterial stiffness has been recognized as a marker of cardiovascular disease and associated with long-term worse clinical outcomes in several populations. Age, hypertension, smoking, and dyslipidemia, known as traditional vascular risk factors, as well as diabetes, obesity, and systemic inflammation lead to both atherosclerosis and arterial stiffness. Targeting multiple modifiable risk factors has become the main therapeutic strategy to improve arterial stiffness in patients at high cardiovascular risk. Additionally to life style modifications, long-term ω-3 fatty acids (fish oil) supplementation in diet may improve arterial stiffness in the population with hypertension or metabolic syndrome. Pharmacological treatment such as renin-angiotensin-aldosterone system antagonists, metformin, and 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors were useful in individuals with hypertension and diabetes. In obese population with obstructive sleep apnea, weight reduction, aerobic exercise, and continuous positive airway pressure treatment may also improve arterial stiffness. In the populations with chronic inflammatory disease such as rheumatoid arthritis, a use of antibodies against tumor necrosis factor-alpha could work effectively. Other therapeutic options such as renal sympathetic nerve denervation for patients with resistant hypertension are investigated in many ongoing clinical trials. Therefore our comprehensive review provides knowledge in detail regarding many aspects of pathogenesis, measurement, and management of arterial stiffness in several populations, which would be helpful for physicians to make clinical decision. PMID:26635922

  5. Metabolic shift from withasteroid formation to phenylpropanoid accumulation in cryptogein-cotransformed hairy roots of Withania somnifera (L.) Dunal.

    PubMed

    Sil, Bipradut; Mukherjee, Chiranjit; Jha, Sumita; Mitra, Adinpunya

    2015-07-01

    Cotransformed hairy roots containing a gene that encodes a fungal elicitor protein, β-cryptogein, were established in Withania somnifera, a medicinal plant widely used in Indian systems of medicine. To find out whether β-cryptogein protein endogenously elicits the pathway of withasteroid biosynthesis, withaferin A and withanolide A contents along with transcript accumulation of farnesyl pyrophosphate (FPP) synthase, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR), and sterol glycosyltransferase (SGT) were analyzed in both cryptogein-cotransformed and normal hairy roots of W. somnifera. It was observed that the withaferin A and withanolide A contents were drastically higher in normal hairy roots than cryptogein-cotransformed ones. Similar trends were also observed on the levels of transcript accumulation. Subsequently, the enzyme activity of phenylalanine ammonia lyase (PAL), one of the key enzymes of phenylpropanoid pathway, was measured in both cryptogein-cotransformed and normal hairy roots of W. somnifera along with the levels of PAL transcript accumulation. Upliftment of PAL activity was observed in cryptogein-cotransformed hairy roots as compared to the normal ones, and the PAL expression also reflected a similar trend, i.e., enhanced expression in the cryptogein-cotransformed lines. Upliftment of wall-bound ferulic acid accumulation was also observed in the cryptogein-cotransformed lines, as compared to normal hairy root lines. Thus, the outcome of the above studies suggests a metabolic shift from withanolide accumulation to phenylpropanoid biosynthesis in cryptogein-cotransformed hairy roots of W. somnifera.

  6. Major Peptides from Amaranth (Amaranthus cruentus) Protein Inhibit HMG-CoA Reductase Activity

    PubMed Central

    Soares, Rosana Aparecida Manólio; Mendonça, Simone; de Castro, Luíla Ívini Andrade; Menezes, Amanda Caroline Cardoso Corrêa Carlos; Arêas, José Alfredo Gomes

    2015-01-01

    The objective of this study was to identify the major peptides generated by the in vitro hydrolysis of Amaranthus cruentus protein and to verify the effect of these peptides on the activity of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA reductase), a key enzyme in cholesterol biosynthesis. A protein isolate was prepared, and an enzymatic hydrolysis that simulated the in vivo digestion of the protein was performed. After hydrolysis, the peptide mixture was filtered through a 3 kDa membrane. The peptide profile of this mixture was determined by reversed phase high performance chromatography (RP-HPLC), and the peptide identification was performed by LC-ESI MS/MS. Three major peptides under 3 kDa were detected, corresponding to more than 90% of the peptides of similar size produced by enzymatic hydrolysis. The sequences identified were GGV, IVG or LVG and VGVI or VGVL. These peptides had not yet been described for amaranth protein nor are they present in known sequences of amaranth grain protein, except LVG, which can be found in amaranth α‑amylase. Their ability to inhibit the activity of HMG-CoA reductase was determined, and we found that the sequences GGV, IVG, and VGVL, significantly inhibited this enzyme, suggesting a possible hypocholesterolemic effect. PMID:25690031

  7. Inhibition of fatty acid and cholesterol synthesis by stimulation of AMP-activated protein kinase.

    PubMed

    Henin, N; Vincent, M F; Gruber, H E; Van den Berghe, G

    1995-04-01

    AMP-activated protein kinase is a multisubstrate protein kinase that, in liver, inactivates both acetyl-CoA carboxylase, the rate-limiting enzyme of fatty acid synthesis, and 3-hydroxy-3-methyl-glutaryl-CoA reductase, the rate-limiting enzyme of cholesterol synthesis. AICAR (5-amino 4-imidazolecarboxamide ribotide, ZMP) was found to stimulate up to 10-fold rat liver AMP-activated protein kinase, with a half-maximal effect at approximately 5 mM. In accordance with previous observations, addition to suspensions of isolated rat hepatocytes of 50-500 microM AICAriboside, the nucleoside corresponding to ZMP, resulted in the accumulation of millimolar concentrations of the latter. This was accompanied by a dose-dependent inactivation of both acetyl-CoA carboxylase and 3-hydroxy-3-methylglutaryl-CoA reductase. Addition of 50-500 microM AICAriboside to hepatocyte suspensions incubated in the presence of various substrates, including glucose and lactate/pyruvate, caused a parallel inhibition of both fatty acid and cholesterol synthesis. With lactate/pyruvate (10/1 mM), half-maximal inhibition was obtained at approximately 100 microM, and near-complete inhibition at 500 microM AICAriboside. These findings open new perspectives for the simultaneous control of triglyceride and cholesterol synthesis by pharmacological stimulators of AMP-activated protein kinase.

  8. Impact of oxygen level in gaseous phase on gene transcription and ganoderic acid biosynthesis in liquid static cultures of Ganoderma lucidum.

    PubMed

    Zhang, Wen-Xian; Tang, Ya-Jie; Zhong, Jian-Jiang

    2010-08-01

    Liquid static cultivation of Ganoderma lucidum was previously found to be very efficient for improving the production of its valuable antitumor compound ganoderic acid (GA) (Fang and Zhong in Biotechnol Prog 18:51-54, 2002). In this work, effects of oxygen concentration within the range of 21-100% (v/v) in the gaseous phase on the mycelia growth, GA production, and gene transcription of key enzymes for GA biosynthesis in liquid static cultures of G. lucidum were investigated. A high cell density of 29.8 +/- 1.7 g/l DW and total GA production of 1427.2 +/- 74.2 mg/l were obtained under an optimal gaseous O(2) level of 80%. The expression of 3-hydroxy-3-methyl-glutaryl-CoA reductase, squalene synthase and lanosterol synthase genes of GA biosynthetic pathway as detected by quantitative real-time PCR was also affected by the gaseous oxygen concentration in the liquid static culture. H(2)O(2) was generated as reactive oxygen species in response to high oxygen concentrations in the gas phase, and it seemed to be involved in the regulation of GA biosynthesis. The information obtained in this study provided an insight into the role of gaseous O(2) in the GA production and it will be helpful for further enhancing its productivity.

  9. Synergistic Radioprotection by Gamma-Tocotrienol and Pentoxifylline: Role of cAMP Signaling

    PubMed Central

    Kulkarni, Shilpa; Chakraborty, Kushal; Kumar, K. Sree; Kao, Tzu-Cheg; Hauer-Jensen, Martin; Ghosh, Sanchita P.

    2013-01-01

    Purpose. This study was designed to determine the efficacy and mechanisms of radioprotection by the combination of gamma-tocotrienol (GT3) and pentoxifylline (PTX) against acute radiation injury. Materials and Methods. Post-irradiation survival was monitored to determine the most efficacious dose and time of administration of PTX. Dose reduction factor (DRF) was calculated to compare the radioprotective efficacy of the combination. To determine the mechanism of synergistic radioprotection by the combination, mevalonate or calmodulin were coadministered with the GT3-PTX combination. Mevalonate was used to reverse the inhibitory effect of GT3 on 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR), and calmodulin was used to reverse the inhibition of phosphodiesterase (PDE) by PTX. Results. The combination was most effective when 200 mg/kg of PTX was administered 15 min before irradiation along with 200 mg/kg of GT3 (−24 h) and resulted in a DRF of 1.5. White blood cells and neutrophil counts showed accelerated recovery in GT3-PTX-treated groups compared to GT3. Mevalonate had no effect on the radioprotection of GT3-PTX; calmodulin abrogated the synergistic radioprotection by GT3-PTX. Conclusion. The mechanism of radioprotection by GT3-PTX may involve PDE inhibition. PMID:24959559

  10. Cell type-specific delivery of short interfering RNAs by dye-functionalised theranostic nanoparticles

    NASA Astrophysics Data System (ADS)

    Press, Adrian T.; Traeger, Anja; Pietsch, Christian; Mosig, Alexander; Wagner, Michael; Clemens, Mark G.; Jbeily, Nayla; Koch, Nicole; Gottschaldt, Michael; Bézière, Nicolas; Ermolayev, Volodymyr; Ntziachristos, Vasilis; Popp, Jürgen; Kessels, Michael M.; Qualmann, Britta; Schubert, Ulrich S.; Bauer, Michael

    2014-12-01

    Efficient delivery of short interfering RNAs reflects a prerequisite for the development of RNA interference therapeutics. Here, we describe highly specific nanoparticles, based on near infrared fluorescent polymethine dye-derived targeting moieties coupled to biodegradable polymers. The fluorescent dye, even when coupled to a nanoparticle, mimics a ligand for hepatic parenchymal uptake transporters resulting in hepatobiliary clearance of approximately 95% of the dye within 45 min. Body distribution, hepatocyte uptake and excretion into bile of the dye itself, or dye-coupled nanoparticles can be tracked by intravital microscopy or even non-invasively by multispectral optoacoustic tomography. Efficacy of delivery is demonstrated in vivo using 3-hydroxy-3-methyl-glutaryl-CoA reductase siRNA as an active payload resulting in a reduction of plasma cholesterol levels if siRNA was formulated into dye-functionalised nanoparticles. This suggests that organ-selective uptake of a near infrared dye can be efficiently transferred to theranostic nanoparticles allowing novel possibilities for personalised silencing of disease-associated genes.

  11. Sufficient production of geranylgeraniol is required to maintain endotoxin tolerance in macrophages.

    PubMed

    Kim, Jinyong; Lee, Joon No; Ye, James; Hao, Rosy; Debose-Boyd, Russell; Ye, Jin

    2013-12-01

    Endotoxin tolerance allows macrophages to produce large quantities of proinflammatory cytokines immediately after their contact with lipopolysaccharides (LPSs), but prevents their further production after repeated exposure to LPSs. While this response is known to prevent overproduction of proinflammatory cytokines, the mechanism through which endotoxin tolerance is established has not been identified. In the current study, we demonstrate that sufficient production of geranylgeraniol (GGOH) in macrophages is required to maintain endotoxin tolerance. We show that increased synthesis of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR) protein following LPS treatment is required to produce enough GGOH to inhibit expression of Malt1, a protein known to stimulate expression of proinflammatory cytokines, in macrophages repeatedly exposed to LPSs. Depletion of GGOH caused by inhibition of HMGCR led to increased Malt1 expression in macrophages subjected to repeated exposure to LPSs. Consequently, endotoxin tolerance was impaired, and production of interleukin 1-β and other proinflammatory cytokines was markedly elevated in these cells. These results suggest that insufficient production of GGOH in macrophages may cause autoinflammatory diseases.

  12. Effects of dietary cholesterol supplementation on growth and cholesterol metabolism of rainbow trout (Oncorhynchus mykiss) fed diets with cottonseed meal or rapeseed meal.

    PubMed

    Deng, Junming; Zhang, Xi; Long, Xiaowen; Tao, Linli; Wang, Zhen; Niu, Guoyi; Kang, Bin

    2014-12-01

    This study was conducted to evaluate the effects of cholesterol on growth and cholesterol metabolism of rainbow trout (Oncorhynchus mykiss) fed diets with cottonseed meal (CSM) or rapeseed meal (RSM). Four experimental diets were formulated to contain 550 g kg(-1) CSM or 450 g kg(-1) RSM with or without 9 g kg(-1) supplemental cholesterol. Growth rate and feed utilization efficiency of fish fed diets with 450 g kg(-1) RSM were inferior to fish fed diets with 550 g kg(-1) CSM regardless of cholesterol level. Dietary cholesterol supplementation increased the growth rate of fish fed diets with RSM, and growth rate and feed utilization efficiency of fish fed diets with CSM. Similarly, dietary cholesterol supplementation increased the plasma total cholesterol (TC), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triiodothyronine levels, but decreased the plasma triglycerides and cortisol levels of fish fed diets with RSM or CSM. In addition, supplemental cholesterol increased the free cholesterol and TC levels in intestinal contents, but decreased the hepatic 3-hydroxy-3-methyl-glutaryl-CoA reductase activity of fish fed diets with RSM or CSM. These results indicate that 9 g kg(-1) cholesterol supplementation seems to improve the growth of rainbow trout fed diets with CSM or RSM, and the growth-promoting action may be related to the alleviation of the negative effects caused by antinutritional factors and/or make up for the deficiency of endogenous cholesterol in rainbow trout.

  13. Membrane plasmalogen composition and cellular cholesterol regulation: a structure activity study

    PubMed Central

    2010-01-01

    Background Disrupted cholesterol regulation leading to increased circulating and membrane cholesterol levels is implicated in many age-related chronic diseases such as cardiovascular disease (CVD), Alzheimer's disease (AD), and cancer. In vitro and ex vivo cellular plasmalogen deficiency models have been shown to exhibit impaired intra- and extra-cellular processing of cholesterol. Furthermore, depleted brain plasmalogens have been implicated in AD and serum plasmalogen deficiencies have been linked to AD, CVD, and cancer. Results Using plasmalogen deficient (NRel-4) and plasmalogen sufficient (HEK293) cells we investigated the effect of species-dependent plasmalogen restoration/augmentation on membrane cholesterol processing. The results of these studies indicate that the esterification of cholesterol is dependent upon the amount of polyunsaturated fatty acid (PUFA)-containing ethanolamine plasmalogen (PlsEtn) present in the membrane. We further elucidate that the concentration-dependent increase in esterified cholesterol observed with PUFA-PlsEtn was due to a concentration-dependent increase in sterol-O-acyltransferase-1 (SOAT1) levels, an observation not reproduced by 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase inhibition. Conclusion The present study describes a novel mechanism of cholesterol regulation that is consistent with clinical and epidemiological studies of cholesterol, aging and disease. Specifically, the present study describes how selective membrane PUFA-PlsEtn enhancement can be achieved using 1-alkyl-2-PUFA glycerols and through this action reduce levels of total and free cholesterol in cells. PMID:20546600

  14. Lovastatin in Aspergillus terreus: Fermented Rice Straw Extracts Interferes with Methane Production and Gene Expression in Methanobrevibacter smithii

    PubMed Central

    Liang, Juan Boo; Ho, Yin Wan; Mohamad, Rosfarizan; Goh, Yong Meng; Shokryazdan, Parisa; Chin, James

    2013-01-01

    Lovastatin, a natural byproduct of some fungi, is able to inhibit HMG-CoA (3-hydroxy-3methyl glutaryl CoA) reductase. This is a key enzyme involved in isoprenoid synthesis and essential for cell membrane formation in methanogenic Archaea. In this paper, experiments were designed to test the hypothesis that lovastatin secreted by Aspergillus terreus in fermented rice straw extracts (FRSE) can inhibit growth and CH4 production in Methanobrevibacter smithii (a test methanogen). By HPLC analysis, 75% of the total lovastatin in FRSE was in the active hydroxyacid form, and in vitro studies confirmed that this had a stronger effect in reducing both growth and CH4 production in M. smithii compared to commercial lovastatin. Transmission electron micrographs revealed distorted morphological divisions of lovastatin- and FRSE-treated M. smithii cells, supporting its role in blocking normal cell membrane synthesis. Real-time PCR confirmed that both commercial lovastatin and FRSE increased (P < 0.01) the expression of HMG-CoA reductase gene (hmg). In addition, expressions of other gene transcripts in M. smithii. with a key involvement in methanogenesis were also affected. Experimental confirmation that CH4 production is inhibited by lovastatin in A. terreus-fermented rice straw paves the way for its evaluation as a feed additive for mitigating CH4 production in ruminants. PMID:23710454

  15. Impact of single-dose nandrolone decanoate on gonadotropins, blood lipids and HMG CoA reductase in healthy men.

    PubMed

    Gårevik, N; Börjesson, A; Choong, E; Ekström, L; Lehtihet, M

    2016-06-01

    The aim was to study the effect and time profile of a single dose of nandrolone decanoate (ND) on gonadotropins, blood lipids and HMG CoA reductase [3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR)] in healthy men. Eleven healthy male participants aged 29-46 years were given a single dose of 150 mg ND as an intramuscular dose of Deca Durabol®, Organon. Blood samples for sex hormones, lipids and HMGCR mRNA analysis were collected prior to ND administration day 0, 4 and 14. A significant suppression of luteinising hormone (LH) and follicle-stimulating hormone (FSH) was seen after 4 days. Total testosterone and bioavailable testosterone level decreased significantly throughout the observed study period. A small but significant decrease in sexual hormone-binding globulin (SHBG) was seen after 4 days but not after 14 days. Total serum (S)-cholesterol and plasma (P)-apolipoprotein B (ApoB) increased significantly after 14 days. In 80% of the individuals, the HMGCR mRNA level was increased 4 days after the ND administration. Our results show that a single dose of 150 mg ND increases (1) HMGCR mRNA expression, (2) total S-cholesterol and (3) P-ApoB level. The long-term consequences on cardiovascular risk that may appear in users remain to be elucidated.

  16. Lipid profile of rats fed blends of rice bran oil in combination with sunflower and safflower oil.

    PubMed

    Sunitha, T; Manorama, R; Rukmini, C

    1997-01-01

    This study was undertaken to assess the effect of blended oils, i.e., polyunsaturated fatty acid (PUFA) rich vegetable oils like safflower oil (SFO) and sunflower oil (SNO) with the unconventional and hypocholesterolemic rice bran oil (RBO) on the serum lipid profile of rats. Rats fed RBO+SNO/SFO at 70:30 ratio for a period of 28 days showed significantly (p < 0.05) lower levels of total cholesterol (TC), triglycerides (TG) and low density lipoprotein (LDL) cholesterol and increased high density lipoprotein (HDL) cholesterol in animals fed a high cholesterol diet (HCD) and cholesterol free diet (CFD). Liver total cholesterol (TC) and triglycerides (TG) were also reduced. Fecal excretion of neutral sterols and bile acids was increased with use of RBO blends. RBO, which is rich in tocopherols and tocotrienols, may improve the oxidative stability of the blends. Tocotrienols are known to inhibit 3-hydroxy, 3-methyl, glutaryl CoA (HMG-COA) reductase (rate limiting enzyme in cholesterol biosynthesis), resulting in hypocholesterolemia. In addition to improving the lipid profile by lowering TC, TG and LDL-C and increasing HDL-C, blending of RBO with other oils can result in an economic advantage of lower prices.

  17. Structural and functional consequences of coenzyme binding to the inactive asian variant of mitochondrial aldehyde dehydrogenase: roles of residues 475 and 487.

    PubMed

    Larson, Heather N; Zhou, Jianzhong; Chen, Zhiqiang; Stamler, Jonathan S; Weiner, Henry; Hurley, Thomas D

    2007-04-27

    The common mitochondrial aldehyde dehydrogenase (ALDH2) ALDH2(*)2 polymorphism is associated with impaired ethanol metabolism and decreased efficacy of nitroglycerin treatment. These physiological effects are due to the substitution of Lys for Glu-487 that reduces the k(cat) for these processes and increases the K(m) for NAD(+), as compared with ALDH2. In this study, we sought to understand the nature of the interactions that give rise to the loss of structural integrity and low activity in ALDH2(*)2 even when complexed with coenzyme. Consequently, we have solved the crystal structure of ALDH2(*)2 complexed with coenzyme to 2.5A(.) We have also solved the structures of a mutated form of ALDH2 where Arg-475 is replaced by Gln (R475Q). The structural and functional properties of the R475Q enzyme are intermediate between those of wild-type and the ALDH2(*)2 enzymes. In both cases, the binding of coenzyme restores most of the structural deficits observed in the apoenzyme structures. The binding of coenzyme to the R475Q enzyme restores its structure and catalytic properties to near wild-type levels. In contrast, the disordered helix within the coenzyme binding pocket of ALDH2(*)2 is reordered, but the active site is only partially reordered. Consistent with the structural data, ALDH2(*)2 showed a concentration-dependent increase in esterase activity and nitroglycerin reductase activity upon addition of coenzyme, but the levels of activity do not approach those of the wild-type enzyme or that of the R475Q enzyme. The data presented shows that Glu-487 maintains a critical function in linking the structure of the coenzyme-binding site to that of the active site through its interactions with Arg-264 and Arg-475, and in doing so, creates the stable structural scaffold conducive to catalysis.

  18. Structural and Functional Consequences of Coenzyme Binding to the Inactive Asian Variant of Mitochondrial Aldehyde Dehydrogenase: Roles of Residues 475 and 487

    SciTech Connect

    Larson,H.; Zhou, J.; Chen, Z.; Stamler, J.; Weiner, H.; Hurley, T.

    2007-01-01

    The common mitochondrial aldehyde dehydrogenase (ALDH2) ALDH2*2 polymorphism is associated with impaired ethanol metabolism and decreased efficacy of nitroglycerin treatment. These physiological effects are due to the substitution of Lys for Glu-487 that reduces the k{sub cat} for these processes and increases the K{sub m} for NAD{sup +}, as compared with ALDH2. In this study, we sought to understand the nature of the interactions that give rise to the loss of structural integrity and low activity in ALDH2*2 even when complexed with coenzyme. Consequently, we have solved the crystal structure of ALDH2*2 complexed with coenzyme to 2.5 {angstrom}. We have also solved the structures of a mutated form of ALDH2 where Arg-475 is replaced by Gln (R475Q). The structural and functional properties of the R475Q enzyme are intermediate between those of wild-type and the ALDH2*2 enzymes. In both cases, the binding of coenzyme restores most of the structural deficits observed in the apoenzyme structures. The binding of coenzyme to the R475Q enzyme restores its structure and catalytic properties to near wild-type levels. In contrast, the disordered helix within the coenzyme binding pocket of ALDH2*2 is reordered, but the active site is only partially reordered. Consistent with the structural data, ALDH2*2 showed a concentration-dependent increase in esterase activity and nitroglycerin reductase activity upon addition of coenzyme, but the levels of activity do not approach those of the wild-type enzyme or that of the R475Q enzyme. The data presented shows that Glu-487 maintains a critical function in linking the structure of the coenzyme binding site to that of the active site through its interactions with Arg-264 and Arg-475, and in doing so, creates the stable structural scaffold conducive to catalysis.

  19. New insights into the binding mode of coenzymes: structure of Thermus thermophilus Delta1-pyrroline-5-carboxylate dehydrogenase complexed with NADP+.

    PubMed

    Inagaki, Eiji; Ohshima, Noriyasu; Sakamoto, Keiko; Babayeva, Nigar D; Kato, Hiroaki; Yokoyama, Shigeyuki; Tahirov, Tahir H

    2007-06-01

    Delta(1)-Pyrroline-5-carboxylate dehydrogenase (P5CDh) is known to preferentially use NAD(+) as a coenzyme. The k(cat) value of Thermus thermophilus P5CDh (TtP5CDh) is four times lower for NADP(+) than for NAD(+). The crystal structure of NADP(+)-bound TtP5CDh was solved in order to study the structure-activity relationships for the coenzymes. The binding mode of NADP(+) is essentially identical to that in the previously solved NAD(+)-bound form, except for the regions around the additional 2'-phosphate group of NADP(+). The coenzyme-binding site can only accommodate this group by the rotation of a glutamate residue and subtle shifts in the main chain. The 2'-phosphate of NADP(+) increases the number of hydrogen bonds between TtP5CDh and NADP(+) compared with that between TtP5CDh and NAD(+). Furthermore, the phosphate of the bound NADP(+) would restrict the ;bending' of the coenzyme because of steric hindrance. Such bending is important for dissociation of the coenzymes. These results provide a plausible explanation of the lower turnover rate of NADP(+) compared with NAD(+).

  20. LC/MS/MS analysis of α-tocopherol and coenzyme Q10 content in lyophilized royal jelly, beebread and drone homogenate.

    PubMed

    Hryniewicka, Marta; Karpinska, Agnieszka; Kijewska, Marta; Turkowicz, Monika Joanna; Karpinska, Joanna

    2016-11-01

    This study shows the results of application liquid chromatography-tandem mass spectrometry (LC/MS/MS) for assay of the content of α-tocopherol and coenzyme Q10 in bee products of animal origin, i.e. royal jelly, beebread and drone homogenate. The biological matrix was removed using extraction with n-hexane. It was found that drone homogenate is a rich source of coenzyme Q10 . It contains only 8 ± 1 µg/g of α-tocopherol and 20 ± 2 µg/g of coenzyme Q10 . The contents of assayed compounds in royal jelly were 16 ± 3 and 8 ± 0.2 µg/g of α-tocopherol and coenzyme Q10 , respectively. Beebread appeared to be the richest of α-tocopherol. Its level was 80 ± 30 µg/g, while the level of coenzyme Q10 was only 11.5 ± 0.3 µg/g. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Re-engineering the discrimination between the oxidized coenzymes NAD+ and NADP+ in clostridial glutamate dehydrogenase and a thorough reappraisal of the coenzyme specificity of the wild-type enzyme.

    PubMed

    Capone, Marina; Scanlon, David; Griffin, Joanna; Engel, Paul C

    2011-07-01

    Clostridial glutamate dehydrogenase mutants, designed to accommodate the 2'-phosphate of disfavoured NADPH, showed the expected large specificity shifts with NAD(P)H. Puzzlingly, similar assays with oxidized cofactors initially revealed little improvement with NADP(+) , although rates with NAD(+) were markedly diminished. This article reveals that the enzyme's discrimination in favour of NAD(+) and against NADP(+) had been greatly underestimated and has indeed been abated by a factor of > 16,000 by the mutagenesis. Initially, stopped-flow studies of the wild-type enzyme showed a burst increase of A(340) with NADP(+) but not NAD(+), with amplitude depending on the concentration of the coenzyme, rather than enzyme. Amplitude also varied with the commercial source of the NADP(+). FPLC, HPLC and mass spectrometry identified NAD(+) contamination ranging from 0.04 to 0.37% in different commercial samples. It is now clear that apparent rates of NADP(+) utilization mainly reflected the reduction of contaminating NAD(+), creating an entirely false view of the initial coenzyme specificity and also of the effects of mutagenesis. Purification of the NADP(+) eliminated the burst. With freshly purified NADP(+), the NAD(+) : NADP(+) activity ratio under standard conditions, previously estimated as 300 : 1, is 11,000. The catalytic efficiency ratio is even higher at 80,000. Retested with pure cofactor, mutants showed marked specificity shifts in the expected direction, for example, 16 200 fold change in catalytic efficiency ratio for the mutant F238S/P262S, confirming that the key structural determinants of specificity have been successfully identified. Of wider significance, these results underline that, without purification, even the best commercial coenzyme preparations are inadequate for such studies.

  2. Methyl group dynamics in glassy, polycrystalline, and liquid coenzyme Q10 studied by quasielastic neutron scattering

    NASA Astrophysics Data System (ADS)

    Smuda, Christoph; Busch, Sebastian; Wagner, Bernd; Unruh, Tobias

    2008-08-01

    The methyl group rotation of coenzyme Q10 confined in nanosized droplets was studied using quasielastic neutron scattering (QENS). Q10 as an oligoisoprene derivative with ten isoprene units can easily be supercooled in nanodroplets. Fixed window scans and QENS spectra at several temperatures of glassy Q10 were recorded to study the methyl group rotation which can be described by a logarithmic Gaussian distribution of hopping rates for temperatures below the glass transition temperature (Tg~200 K). A mean activation energy of 4.8 kJ/mol with a distribution width of 2.1 kJ/mol was obtained from the evaluation of the QENS spectra. A corresponding analysis of a fixed window scan yielded an average activation energy of 5.1 kJ/mol with a distribution width of 1.8 kJ/mol. The results are compared and discussed with those of chain deuterated polyisoprene-d5. For polycrystalline Q10, the QENS spectra could be described by the same model yielding a similar average activation energy as found for glassy Q10. However, no temperature dependence of the distribution width was observed. Based on the performed low-temperature measurements, the correlation times for the methyl group rotation were extrapolated to temperatures of liquid Q10. The complex dynamics of liquid Q10 could be described by a model yielding an apparent diffusion coefficient, the jump rate of the methyl groups, as well as an overall molecular rotational diffusion coefficient. The correlation times of the methyl group rotation in liquid Q10 at a given temperature T0 coincide with values determined in the glassy phase and extrapolated to T0.

  3. Effects of Coenzyme Q10 on Markers of Inflammation: A Systematic Review and Meta-Analysis

    PubMed Central

    Zhai, Junya; Bo, Yacong; Lu, Yan; Liu, Chunli; Zhang, Lishi

    2017-01-01

    Background/Objective Chronic inflammation contributes to the onset and development of metabolic diseases. Clinical evidence has suggested that coenzyme Q10 (CoQ10) has some effects on inflammatory markers. However, these results are equivocal. The aim of this systematic review was to assess the effects of CoQ10 on serum levels of inflammatory markers in people with metabolic diseases. Methods Electronic databases were searched up to February 2016 for randomized controlled trials (RCTs). The outcome parameters were related to inflammatory factors, including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and C reactive protein (CRP). RevMan software was used for meta-analysis. Meta-regression analysis, Egger line regression test and Begg rank correlation test were performed by STATA software. Results Nine trials involving 428 subjects were included in this meta-analysis. The results showed that compared with control group, CoQ10 supplementation has significantly improved the serum level of CoQ10 by 1.17μg/ml [MD = 1.17, 95% CI (0.47 to 1.87) μg/ml, I2 = 94%]. Meanwhile, it has significantly decreased TNF-α by 0.45 pg/ml [MD = -0.45, 95% CI (-0.67 to -0.24) pg/ml, I2 = 0%]. No significant difference was observed between CoQ10 and placebo with regard to CRP [MD = -0.21, 95% CI (-0.60 to 0.17) mg/L, I2 = 21%] and IL-6 [MD = -0.89, 95% CI (-1.95 to 0.16) pg/ml, I2 = 84%]. Conclusions CoQ10 supplementation may partly improve the process of inflammatory state. The effects of CoQ10 on inflammation should be further investigated by conducting larger sample size and well-defined trials of long enough duration. PMID:28125601

  4. Coenzyme Q10 Status as a Determinant of Muscular Strength in Two Independent Cohorts

    PubMed Central

    Fischer, Alexandra; Onur, Simone; Niklowitz, Petra; Menke, Thomas; Laudes, Matthias; Rimbach, Gerald; Döring, Frank

    2016-01-01

    Aging is associated with sarcopenia, which is a loss of skeletal muscle mass and function. Coenzyme Q10 (CoQ10) is involved in several important functions that are related to bioenergetics and protection against oxidative damage; however, the role of CoQ10 as a determinant of muscular strength is not well documented. The aim of the present study was to evaluate the determinants of muscular strength by examining hand grip force in relation to CoQ10 status, gender, age and body mass index (BMI) in two independent cohorts (n = 334, n = 967). Furthermore, peak flow as a function of respiratory muscle force was assessed. Spearman’s correlation revealed a significant positive association between CoQ10/cholesterol level and hand grip in the basic study population (p<0.01) as well as in the validation population (p<0.001). In the latter, we also found a negative correlation with the CoQ10 redox state (p<0.01), which represents a lower percentage of the reduced form of CoQ10 (ubiquinol) in subjects who exhibit a lower muscular strength. Furthermore, the age of the subjects showed a negative correlation with hand grip (p<0.001), whereas BMI was positively correlated with hand grip (p<0.01), although only in the normal weight subgroup (BMI <25 kg/m2). Analysis of the covariance (ANCOVA) with hand grip as the dependent variable revealed CoQ10/cholesterol as a determinant of muscular strength and gender as the strongest effector of hand grip. In conclusion, our data suggest that both a low CoQ10/cholesterol level and a low percentage of the reduced form of CoQ10 could be an indicator of an increased risk of sarcopenia in humans due to their negative associations to upper body muscle strength, peak flow and muscle mass. PMID:27907044

  5. Characterisation and Skin Distribution of Lecithin-Based Coenzyme Q10-Loaded Lipid Nanocapsules

    NASA Astrophysics Data System (ADS)

    Zhou, Huafeng; Yue, Yang; Liu, Guanlan; Li, Yan; Zhang, Jing; Yan, Zemin; Duan, Mingxing

    2010-10-01

    The purpose of this study was to investigate the influence of the inner lipid ratio on the physicochemical properties and skin targeting of surfactant-free lecithin-based coenzyme Q10-loaded lipid nanocapsules (CoQ10-LNCs). The smaller particle size of CoQ10-LNCs was achieved by high pressure and a lower ratio of CoQ10/GTCC (Caprylic/capric triglyceride); however, the zeta potential of CoQ10-LNCs was above /- 60 mV/ with no distinct difference among them at different ratios of CoQ10/GTCC. Both the crystallisation point and the index decreased with the decreasing ratio of CoQ10/GTCC and smaller particle size; interestingly, the supercooled state of CoQ10-LNCs was observed at particle size below about 200 nm, as verified by differential scanning calorimetry (DSC) in one heating-cooling cycle. The lecithin monolayer sphere structure of CoQ10-LNCs was investigated by cryogenic transmission electron microscopy (Cryo-TEM). The skin penetration results revealed that the distribution of Nile red-loaded CoQ10-LNCs depended on the ratio of inner CoQ10/GTCC; moreover, epidermal targeting and superficial dermal targeting were achieved by the CoQ10-LNCs application. The highest fluorescence response was observed at a ratio of inner CoQ10/GTCC of 1:1. These observations suggest that lecithin-based LNCs could be used as a promising topical delivery vehicle for lipophilic compounds.

  6. The bioinformatics of nucleotide sequence coding for proteins requiring metal coenzymes and proteins embedded with metals

    NASA Astrophysics Data System (ADS)

    Tremberger, G.; Dehipawala, Sunil; Cheung, E.; Holden, T.; Sullivan, R.; Nguyen, A.; Lieberman, D.; Cheung, T.

    2015-09-01

    All metallo-proteins need post-translation metal incorporation. In fact, the isotope ratio of Fe, Cu, and Zn in physiology and oncology have emerged as an important tool. The nickel containing F430 is the prosthetic group of the enzyme methyl coenzyme M reductase which catalyzes the release of methane in the final step of methano-genesis, a prime energy metabolism candidate for life exploration space mission in the solar system. The 3.5 Gyr early life sulfite reductase as a life switch energy metabolism had Fe-Mo clusters. The nitrogenase for nitrogen fixation 3 billion years ago had Mo. The early life arsenite oxidase needed for anoxygenic photosynthesis energy metabolism 2.8 billion years ago had Mo and Fe. The selection pressure in metal incorporation inside a protein would be quantifiable in terms of the related nucleotide sequence complexity with fractal dimension and entropy values. Simulation model showed that the studied metal-required energy metabolism sequences had at least ten times more selection pressure relatively in comparison to the horizontal transferred sequences in Mealybug, guided by the outcome histogram of the correlation R-sq values. The metal energy metabolism sequence group was compared to the circadian clock KaiC sequence group using magnesium atomic level bond shifting mechanism in the protein, and the simulation model would suggest a much higher selection pressure for the energy life switch sequence group. The possibility of using Kepler 444 as an example of ancient life in Galaxy with the associated exoplanets has been proposed and is further discussed in this report. Examples of arsenic metal bonding shift probed by Synchrotron-based X-ray spectroscopy data and Zn controlled FOXP2 regulated pathways in human and chimp brain studied tissue samples are studied in relationship to the sequence bioinformatics. The analysis results suggest that relatively large metal bonding shift amount is associated with low probability correlation R

  7. Crystal Structure of the alpha6beta6 Holoenzyme of propionyl-coenzyme A Carboxylase

    SciTech Connect

    Huang, C.; Sadre-Bazzaz, K; Shen, Y; Deng, B; Zhou, Z; Tong, L

    2010-01-01

    Propionyl-coenzyme A carboxylase (PCC), a mitochondrial biotin-dependent enzyme, is essential for the catabolism of the amino acids Thr, Val, Ile and Met, cholesterol and fatty acids with an odd number of carbon atoms. Deficiencies in PCC activity in humans are linked to the disease propionic acidaemia, an autosomal recessive disorder that can be fatal in infants. The holoenzyme of PCC is an {alpha}{sub 6}{beta}{sub 6} dodecamer, with a molecular mass of 750 kDa. The {alpha}-subunit contains the biotin carboxylase (BC) and biotin carboxyl carrier protein (BCCP) domains, whereas the {beta}-subunit supplies the carboxyltransferase (CT) activity. Here we report the crystal structure at 3.2-{angstrom} resolution of a bacterial PCC {alpha}{sub 6}{beta}{sub 6} holoenzyme as well as cryo-electron microscopy (cryo-EM) reconstruction at 15-{angstrom} resolution demonstrating a similar structure for human PCC. The structure defines the overall architecture of PCC and reveals unexpectedly that the {alpha}-subunits are arranged as monomers in the holoenzyme, decorating a central {beta}{sub 6} hexamer. A hitherto unrecognized domain in the {alpha}-subunit, formed by residues between the BC and BCCP domains, is crucial for interactions with the {beta}-subunit. We have named it the BT domain. The structure reveals for the first time the relative positions of the BC and CT active sites in the holoenzyme. They are separated by approximately 55 {angstrom}, indicating that the entire BCCP domain must translocate during catalysis. The BCCP domain is located in the active site of the {beta}-subunit in the current structure, providing insight for its involvement in the CT reaction. The structural information establishes a molecular basis for understanding the large collection of disease-causing mutations in PCC and is relevant for the holoenzymes of other biotin-dependent carboxylases, including 3-methylcrotonyl-CoA carboxylase (MCC) and eukaryotic acetyl-CoA carboxylase (ACC).

  8. Decreased hepatic contents of coenzyme A molecular species in mice after subchronic mild social defeat stress.

    PubMed

    Kubota, Yoshifumi; Goto, Tatsuhiko; Hagiya, Yuki; Chohnan, Shigeru; Toyoda, Atsushi

    2016-01-01

    Social stress may precipitate psychiatric disorders such as depression, which is related to the occurrence of the metabolic syndrome, including obesity and type 2 diabetes. We have evaluated the effects of social stress on central and peripheral metabolism using a model of depression in mice. In the present study, we focused on coenzyme A (CoA) molecular species [i.e. non-esterified CoA (CoASH), acetyl-CoA and malonyl-CoA] which play important roles in numerous metabolic pathways, and we analyzed changes in expression of these molecules in the hypothalamus and liver of adult male mice (C57BL/6J) subjected to 10 days of subchronic mild social defeat stress (sCSDS) with ICR mice as aggressors. Mice (n = 12) exposed to showed hyperphagia- and polydipsia-like symptoms and increased body weight gain compared with control mice which were not affected by exposure to ICR mice (n = 12). To elucidate the underlying metabolic features in the sCSDS model, acetyl-CoA, malonyl-CoA and CoASH tissue levels were analyzed using the acyl-CoA cycling method. The levels of hypothalamic malonyl-CoA, which decreases feeding behavior, were not influenced by sCSDS. However, sCSDS reduced levels of acetyl-CoA, malonyl-CoA and total CoA (sum of the three CoA molecular species) in the liver. Hence, hyperphagia-like symptoms in sCSDS mice evidently occurred independently of hypothalamic malonyl-CoA, but might consequently lead to down-regulation of hepatic CoA via altered expression of nudix hydrolase 7. Future studies should investigate the molecular mechanism(s) underlying the down-regulation of liver CoA pools in sCSDS mice.

  9. Functional characterization of human COQ4, a gene required for Coenzyme Q{sub 10} biosynthesis

    SciTech Connect

    Casarin, Alberto; Trevisson, Eva; Pertegato, Vanessa; Doimo, Mara; Ferrero-Gomez, Maria Lara; Abbadi, Sara; Quinzii, Catarina; Hirano, Michio; Basso, Giuseppe; Salviati, Leonardo

    2008-07-18

    Defects in genes involved in coenzyme Q (CoQ) biosynthesis cause primary CoQ deficiency, a severe multisystem disorders presenting as progressive encephalomyopathy and nephropathy. The COQ4 gene encodes an essential factor for biosynthesis in Saccharomyces cerevisiae. We have identified and cloned its human ortholog, COQ4, which is located on chromosome 9q34.13, and is transcribed into a 795 base-pair open reading frame, encoding a 265 amino acid (aa) protein (Isoform 1) with a predicted N-terminal mitochondrial targeting sequence. It shares 39% identity and 55% similarity with the yeast protein. Coq4 protein has no known enzymatic function, but may be a core component of multisubunit complex required for CoQ biosynthesis. The human transcript is detected in Northern blots as a {approx}1.4 kb single band and is expressed ubiquitously, but at high levels in liver, lung, and pancreas. Transcription initiates at multiple sites, located 333-23 nucleotides upstream of the ATG. A second group of transcripts originating inside intron 1 of the gene encodes a 241 aa protein, which lacks the mitochondrial targeting sequence (isoform 2). Expression of GFP-fusion proteins in HeLa cells confirmed that only isoform 1 is targeted to mitochondria. The functional significance of the second isoform is unknown. Human COQ4 isoform 1, expressed from a multicopy plasmid, efficiently restores both growth in glycerol, and CoQ content in COQ4{sup null} yeast strains. Human COQ4 is an interesting candidate gene for patients with isolated CoQ{sub 10} deficiency.

  10. Oxidative Stress Correlates with Headache Symptoms in Fibromyalgia: Coenzyme Q10 Effect on Clinical Improvement

    PubMed Central

    Cordero, Mario D.; Cano-García, Francisco Javier; Alcocer-Gómez, Elísabet; De Miguel, Manuel; Sánchez-Alcázar, José Antonio

    2012-01-01

    Background Fibromyalgia (FM) is a chronic pain syndrome with unknown etiology and a wide spectrum of symptoms such as allodynia, debilitating fatigue, joint stiffness and migraine. Recent studies have shown some evidences demonstrating that oxidative stress is associated to clinical symptoms in FM of fibromyalgia. We examined oxidative stress and bioenergetic status in blood mononuclear cells (BMCs) and its association to headache symptoms in FM patients. The effects of oral coenzyme Q10 (CoQ10) supplementation on biochemical markers and clinical improvement were also evaluated. Methods We studied 20 FM patients and 15 healthy controls. Clinical parameters were evaluated using the Fibromyalgia Impact Questionnaire (FIQ), visual analogues scales (VAS), and the Headache Impact Test (HIT-6). Oxidative stress was determined by measuring CoQ10, catalase and lipid peroxidation (LPO) levels in BMCs. Bioenergetic status was assessed by measuring ATP levels in BMCs. Results We found decreased CoQ10, catalase and ATP levels in BMCs from FM patients as compared to normal control (P<0.05 and P<0.001, respectively) We also found increased level of LPO in BMCs from FM patients as compared to normal control (P<0.001). Significant negative correlations between CoQ10 or catalase levels in BMCs and headache parameters were observed (r = −0.59, P<0.05; r = −0.68, P<0.05, respectively). Furthermore, LPO levels showed a significant positive correlation with HIT-6 (r = 0.33, P<0.05). Oral CoQ10 supplementation restored biochemical parameters and induced a significant improvement in clinical and headache symptoms (P<0.001). Discussion The results of this study suggest a role for mitochondrial dysfunction and oxidative stress in the headache symptoms associated with FM. CoQ10 supplementation should be examined in a larger placebo controlled trial as a possible treatment in FM. PMID:22532869

  11. Role of energetic coenzyme pools in the production of L-carnitine by Escherichia coli.

    PubMed

    Cánovas, M; Sevilla, A; Bernal, V; Leal, R; Iborra, J L

    2006-11-01

    The aim of this work was to understand the steps controlling the biotransformation of trimethylammonium compounds into L(-)-carnitine by Escherichia coli. The high-cell density reactor steady-state levels of carbon source (glycerol), biotransformation substrate (crotonobetaine), acetate (anaerobiosis product) and fumarate (as an electron acceptor) were pulsed by increasing them fivefold. Following the pulse, the evolution of the enzyme activities involved in the biotransformation process of crotonobetaine into L(-)-carnitine (crotonobetaine hydration), in the synthesis of acetyl-CoA (ACS: acetyl-CoA synthetase and PTA: ATP: acetate phosphotransferase) and in the distribution of metabolites for the tricarboxylic acid (ICDH: isocitrate dehydrogenase) and glyoxylate (ICL: isocitrate lyase) cycles was monitored. In addition, the levels of carnitine, the cell ATP content and the NADH/NAD(+) ratio were measured in order to assess the importance and participation of these energetic coenzymes in the catabolic system. The results provided an experimental demonstration of the important role of the glyoxylate shunt during biotransformation and the need for high levels of ATP to maintain metabolite transport and biotransformation. Moreover, the results obtained for the NADH/NAD(+) pool indicated that it is correlated with the biotransformation process at the NAD(+) regeneration and ATP production level in anaerobiosis. More importantly, a linear correlation between the NADH/NAD(+) ratio and the levels of the ICDH and ICL (carbon and electron flows) and the PTA and ACS (acetate and ATP production and acetyl-CoA synthesis) activity levels was assessed. The main metabolic pathway operating during cell metabolic perturbation with a pulse of glycerol and acetate in the high-cell density membrane reactor was that related to ICDH and ICL, both regulating the carbon metabolism, together with PTA and ACS enzymes (regulating ATP production).

  12. Coenzyme Q10 suppresses Th17 cells and osteoclast differentiation and ameliorates experimental autoimmune arthritis mice.

    PubMed

    Jhun, JooYeon; Lee, Seung Hoon; Byun, Jae-Kyeong; Jeong, Jeong-Hee; Kim, Eun-Kyung; Lee, Jennifer; Jung, Young-Ok; Shin, Dongyun; Park, Sung Hwan; Cho, Mi-La

    2015-08-01

    Coenzyme Q10 (CoQ10) is a lipid-soluble antioxidant synthesized in human body. This enzyme promotes immune system function and can be used as a dietary supplement. Rheumatoid arthritis (RA) is an autoimmune disease leading to chronic joint inflammation. RA results in severe destruction of cartilage and disability. This study aimed to investigate the effect of CoQ10 on inflammation and Th17 cell proliferation on an experimental rheumatoid arthritis (RA) mice model. CoQ10 or cotton seed oil as control was orally administrated once a day for seven weeks to mice with zymosan-induced arthritis (ZIA). Histological analysis of the joints was conducted using immunohistochemistry. Germinal center (GC) B cells, Th17 cells and Treg cells of the spleen tissue were examined by confocal microscopy staining. mRNA expression was measured by real-time PCR and protein levels were estimated by enzyme-linked immunosorbent assay (ELISA). Flow cytometric analysis (FACS) was used to evaluate Th17 cells and Treg cells. CoQ10 mitigated the severity of ZIA and decreased serum immunoglobulin concentrations. CoQ10 also reduced RANKL-induced osteoclastogenesis, inflammatory mediators and oxidant factors. Th17/Treg axis was reciprocally controlled by CoQ10 treatment. Moreover, CoQ10 treatment on normal mouse and human cells cultured in Th17 conditions decreased the number of Th17 cells and enhanced the number of Treg cells. CoQ10 alleviates arthritis in mice with ZIA declining inflammation, Th17 cells and osteoclast differentiation. These findings suggest that CoQ10 can be a potential therapeutic substance for RA.

  13. Coenzyme Q(10) and selenium in statin-associated myopathy treatment.

    PubMed

    Fedacko, Jan; Pella, Daniel; Fedackova, Petra; Hänninen, Osmo; Tuomainen, Petri; Jarcuska, Peter; Lopuchovsky, Tomas; Jedlickova, Lucia; Merkovska, Lucia; Littarru, Gian Paolo

    2013-02-01

    The objective of this study was to evaluate the possible benefits of coenzyme Q10 and selenium supplementation administered to patients with statin-associated myopathy (SAM). Sixty eligible patients entered the pilot study. Laboratory examination (CoQ10, selenium, creatin kinase) and intensity of SAM (visual scale) were performed at baseline, after 1 month, and at the end of study at month 3. Plasma levels of CoQ10 increased from 0.81 ± 0.39 to 3.31 ± 1.72 μmol/L in the active group of patients treated by CoQ10, compared with the placebo (p = 0.001). Also, the symptoms of SAM significantly improved in the active group (p < 0.001): the intensity of muscle pain decreased from 6.7 ± 1.72 to 3.2 ± 2.1 (p < 0.01, -53.4 ± 28.2%); muscle weakness decreased from 7.0 ± 1.63 to 2.8 ± 2.34 (p < 0.01, -60 ± 24.0%); muscle cramps decreased from 5.33 ± 2.06 to 1.86 ± 2.42, p < 0.01, -65 ± 28%); tiredness decreased from the initial 6.7 ± 1.34 to 1.2 ± 1.32 (p < 0.01, -82 ± 22%). We did not observe any significant changes in the placebo group. In conclusion, supplementation of statin-treated patients with CoQ10 resulted in a decrease in the symptoms of SAM, both in absolute numbers and intensity. Additional selenium supplementation was not associated with any statistically significant decrease of SAM. However, it is not possible to draw any definite conclusions, even though this study was carried out in double-blind fashion, because it involved a small number of patients.

  14. Functional conservation of coenzyme Q biosynthetic genes among yeasts, plants, and humans.

    PubMed

    Hayashi, Kazuhiro; Ogiyama, Yuki; Yokomi, Kazumasa; Nakagawa, Tsuyoshi; Kaino, Tomohiro; Kawamukai, Makoto

    2014-01-01

    Coenzyme Q (CoQ) is an essential factor for aerobic growth and oxidative phosphorylation in the electron transport system. The biosynthetic pathway for CoQ has been proposed mainly from biochemical and genetic analyses of Escherichia coli and Saccharomyces cerevisiae; however, the biosynthetic pathway in higher eukaryotes has been explored in only a limited number of studies. We previously reported the roles of several genes involved in CoQ synthesis in the fission yeast Schizosaccharomyces pombe. Here, we expand these findings by identifying ten genes (dps1, dlp1, ppt1, and coq3-9) that are required for CoQ synthesis. CoQ10-deficient S. pombe coq deletion strains were generated and characterized. All mutant fission yeast strains were sensitive to oxidative stress, produced a large amount of sulfide, required an antioxidant to grow on minimal medium, and did not survive at the stationary phase. To compare the biosynthetic pathway of CoQ in fission yeast with that in higher eukaryotes, the ability of CoQ biosynthetic genes from humans and plants (Arabidopsis thaliana) to functionally complement the S. pombe coq deletion strains was determined. With the exception of COQ9, expression of all other human and plant COQ genes recovered CoQ10 production by the fission yeast coq deletion strains, although the addition of a mitochondrial targeting sequence was required for human COQ3 and COQ7, as well as A. thaliana COQ6. In summary, this study describes the functional conservation of CoQ biosynthetic genes between yeasts, humans, and plants.

  15. Pseudomonas aeruginosa PqsA is an anthranilate-coenzyme A ligase.

    PubMed

    Coleman, James P; Hudson, L Lynn; McKnight, Susan L; Farrow, John M; Calfee, M Worth; Lindsey, Claire A; Pesci, Everett C

    2008-02-01

    Pseudomonas aeruginosa is an opportunistic human pathogen which relies on several intercellular signaling systems for optimum population density-dependent regulation of virulence genes. The Pseudomonas quinolone signal (PQS) is a 3-hydroxy-4-quinolone with a 2-alkyl substitution which is synthesized by the condensation of anthranilic acid with a 3-keto-fatty acid. The pqsABCDE operon has been identified as being necessary for PQS production, and the pqsA gene encodes a predicted protein with homology to acyl coenzyme A (acyl-CoA) ligases. In order to elucidate the first step of the 4-quinolone synthesis pathway in P. aeruginosa, we have characterized the function of the pqsA gene product. Extracts prepared from Escherichia coli expressing PqsA were shown to catalyze the formation of anthraniloyl-CoA from anthranilate, ATP, and CoA. The PqsA protein was purified as a recombinant His-tagged polypeptide, and this protein was shown to have anthranilate-CoA ligase activity. The enzyme was active on a variety of aromatic substrates, including benzoate and chloro and fluoro derivatives of anthranilate. Inhibition of PQS formation in vivo was observed for the chloro- and fluoroanthranilate derivatives, as well as for several analogs which were not PqsA enzymatic substrates. These results indicate that the PqsA protein is responsible for priming anthranilate for entry into the PQS biosynthetic pathway and that this enzyme may serve as a useful in vitro indicator for potential agents to disrupt quinolone signaling in P. aeruginosa.

  16. Acetoacetyl Coenzyme A Reductase and Polyhydroxybutyrate Synthesis in Rhizobium (Cicer) sp. Strain CC 1192

    PubMed Central

    Chohan, Shahid N.; Copeland, Les

    1998-01-01

    Biochemical controls that regulate the biosynthesis of poly-3-hydroxybutyrate (PHB) were investigated in Rhizobium (Cicer) sp. strain CC 1192. This species is of interest for studying PHB synthesis because the polymer accumulates to a large extent in free-living cells but not in bacteroids during nitrogen-fixing symbiosis with chickpea (Cicer arietinum L.) plants. Evidence is presented that indicates that CC 1192 cells retain the enzymic capacity to synthesize PHB when they differentiate from the free-living state to the bacteroid state. This evidence includes the incorporation by CC 1192 bacteroids of radiolabel from [14C]malate into 3-hydroxybutyrate which was derived by chemically degrading insoluble material from bacteroid pellets. Furthermore, the presence of an NADPH-dependent acetoacetyl coenzyme A (CoA) reductase, which was specific for R-(−)-3-hydroxybutyryl-CoA and NADP+ in the oxidative direction, was demonstrated in extracts from free-living and bacteroid cells of CC 1192. Activity of this enzyme in the reductive direction appeared to be regulated at the biochemical level mainly by the availability of substrates. The CC 1192 cells also contained an NADH-specific acetoacetyl-CoA reductase which oxidized S-(+)-3-hydroxybutyryl-CoA. A membrane preparation from CC 1192 bacteroids readily oxidized NADH but not NADPH, which is suggested to be a major source of reductant for nitrogenase. Thus, a high ratio of NADPH to NADP+, which could enhance delivery of reductant to nitrogenase, could also favor the reduction of acetoacetyl-CoA for PHB synthesis. This would mean that fine controls that regulate the partitioning of acetyl-CoA between citrate synthase and 3-ketothiolase are important in determining whether PHB accumulates. PMID:9687441

  17. Adenosine 5'-tetraphosphate and adenosine 5'-pentaphosphate are synthesized by yeast acetyl coenzyme A synthetase.

    PubMed Central

    Guranowski, A; Günther Sillero, M A; Sillero, A

    1994-01-01

    Yeast (Saccharomyces cerevisiae) acetyl coenzyme A (CoA) synthetase (EC 6.2.1.1) catalyzes the synthesis of adenosine 5'-tetraphosphate (P4A) and adenosine 5'-pentaphosphate (p5A) from ATP and tri- or tetrapolyphosphate (P3 or P4), with relative velocities of 7:1, respectively. Of 12 nucleotides tested as potential donors of nucleotidyl moiety, only ATP, adenosine-5'-O-[3-thiotriphosphate], and acetyl-AMP were substrates, with relative velocities of 100, 62, and 80, respectively. The Km values for ATP, P3, and acetyl-AMP were 0.16, 4.7, and 1.8 mM, respectively. The synthesis of p4A could proceed in the absence of exogenous acetate but was stimulated twofold by acetate, with an apparent Km value of 0.065 mM. CoA did not participate in the synthesis of p4A (p5A) and inhibited the reaction (50% inhibitory concentration of 0.015 mM). At pH 6.3, which was optimum for formation of p4A (p5A), the rate of acetyl-CoA synthesis (1.84 mumol mg-1 min-1) was 245 times faster than the rate of synthesis of p4A measured in the presence of acetate. The known formation of p4A (p5A) in yeast sporulation and the role of acetate may therefore be related to acetyl-CoA synthetase. Images PMID:7910605

  18. Coenzyme Q10 and Heart Failure: A State-of-the-Art Review.

    PubMed

    Sharma, Abhinav; Fonarow, Gregg C; Butler, Javed; Ezekowitz, Justin A; Felker, G Michael

    2016-04-01

    Heart failure (HF) with either preserved or reduced ejection fraction is associated with increased morbidity and mortality. Evidence-based therapies are often limited by tolerability, hypotension, electrolyte disturbances, and renal dysfunction. Coenzyme Q10 (CoQ10) may represent a safe therapeutic option for patients with HF. CoQ10 is a highly lipophilic molecule with a chemical structure similar to vitamin K. Although being a common component of cellular membranes, CoQ10's most prominent role is to facilitate the production of adenosine triphosphate in the mitochondria by participating in redox reactions within the electron transport chain. Numerous trials during the past 30 years examining CoQ10 in patients with HF have been limited by small numbers and lack of contemporary HF therapies. The recent publication of the Q-SYMBIO randomized controlled trial demonstrated a reduction in major adverse cardiovascular events with CoQ10 supplementation in a contemporary HF population. Although having limitations, this study has renewed interest in evaluating CoQ10 supplementation in patients with HF. Current literature suggests that CoQ10 is relatively safe with few drug interactions and side effects. Furthermore, it is already widely available as an over-the-counter supplement. These findings warrant future adequately powered randomized controlled trials of CoQ10 supplementation in patients with HF. This state-of-the-art review summarizes the literature about the mechanisms, clinical data, and safety profile of CoQ10 supplementation in patients with HF.

  19. Kinetics of inhibition of firefly luciferase by dehydroluciferyl-coenzyme A, dehydroluciferin and L-luciferin.

    PubMed

    da Silva, Luís Pinto; da Silva, Joaquim C G Esteves

    2011-06-01

    The inhibition mechanisms of the firefly luciferase (Luc) by three of the most important inhibitors of the reactions catalysed by Luc, dehydroluciferyl-coenzyme A (L-CoA), dehydroluciferin (L) and L-luciferin (L-LH(2)) were investigated. Light production in the presence and absence of these inhibitors (0.5 to 2 μM) has been measured in 50 mM Hepes buffer (pH = 7.5), 10 nM Luc, 250 μM ATP and D-luciferin (D-LH(2), from 3.75 up to 120 μM). Nonlinear regression analysis with the appropriate kinetic models (Henri-Michaelis-Menten and William-Morrison equations) reveals that L-CoA is a non-competitive inhibitor of Luc (K(i) = 0.88 ± 0.03 μM), L is a tight-binding uncompetitive inhibitor (K(i) = 0.00490 ± 0.00009 μM) and L-LH(2) acts as a mixed-type non-competitive-uncompetitive inhibitor (K(i) = 0.68 ± 0.14 μM and αK(i) = 0.34 ± 0.16 μM). The K(m) values obtained for L-CoA, L and L-LH(2) were 16.1 ± 1.0, 16.6 ± 2.3 and 14.4 ± 0.96 μM, respectively. L and L-LH(2) are strong inhibitors of Luc, which may indicate an important role for these compounds in Luc characteristic flash profile. L-CoA K(i) supports the conclusion that CoA can stimulate the light emission reaction by provoking the formation of a weaker inhibitor.

  20. Mercury Methylation Independent of the Acetyl-Coenzyme A Pathway in Sulfate-Reducing Bacteria

    PubMed Central

    Ekstrom, Eileen B.; Morel, François M. M.; Benoit, Janina M.

    2003-01-01

    Sulfate-reducing bacteria (SRB) in anoxic waters and sediments are the major producers of methylmercury in aquatic systems. Although a considerable amount of work has addressed the environmental factors that control methylmercury formation and the conditions that control bioavailability of inorganic mercury to SRB, little work has been undertaken analyzing the biochemical mechanism of methylmercury production. The acetyl-coenzyme A (CoA) pathway has been implicated as being key to mercury methylation in one SRB strain, Desulfovibrio desulfuricans LS, but this result has not been extended to other SRB species. To probe whether the acetyl-CoA pathway is the controlling biochemical process for methylmercury production in SRB, five incomplete-oxidizing SRB strains and two Desulfobacter strains that do not use the acetyl-CoA pathway for major carbon metabolism were assayed for methylmercury formation and acetyl-CoA pathway enzyme activities. Three of the SRB strains were also incubated with chloroform to inhibit the acetyl-CoA pathway. So far, all species that have been found to have acetyl-CoA activity are complete oxidizers that require the acetyl-CoA pathway for basic metabolism, as well as methylate mercury. Chloroform inhibits Hg methylation in these species either by blocking the methylating enzyme or by indirect effects on metabolism and growth. However, we have identified four incomplete-oxidizing strains that clearly do not utilize the acetyl-CoA pathway either for metabolism or mercury methylation (as confirmed by the absence of chloroform inhibition). Hg methylation is thus independent of the acetyl-CoA pathway and may not require vitamin B12 in some and perhaps many incomplete-oxidizing SRB strains. PMID:12957930

  1. Genetic Diversity of Benzoyl Coenzyme A Reductase Genes Detected in Denitrifying Isolates and Estuarine Sediment Communities

    PubMed Central

    Song, Bongkeun; Ward, Bess B.

    2005-01-01

    Benzoyl coenzyme A (benzoyl-CoA) reductase is a central enzyme in the anaerobic degradation of organic carbon, which utilizes a common intermediate (benzoyl-CoA) in the metabolism of many aromatic compounds. The diversity of benzoyl-CoA reductase genes in denitrifying bacterial isolates capable of degrading aromatic compounds and in river and estuarine sediment samples from the Arthur Kill in New Jersey and the Chesapeake Bay in Maryland was investigated. Degenerate primers were developed from the known benzoyl-CoA reductase genes from Thauera aromatica, Rhodopseudomonas palustris, and Azoarcus evansii. PCR amplification detected benzoyl-CoA reductase genes in the denitrifying isolates belonging to α-, β-, or γ-Proteobacteria as well as in the sediment samples. Phylogenetic analysis, sequence similarity comparison, and conserved indel determination grouped the new sequences into either the bcr type (found in T. aromatica and R. palustris) or the bzd type (found in A. evansii). All the Thauera strains and the isolates from the genera Acidovorax, Bradyrhizobium, Paracoccus, Ensifer, and Pseudomonas had bcr-type benzoyl-CoA reductases with amino acid sequence similarities of more than 97%. The genes detected from Azarocus strains were assigned to the bzd type. A total of 50 environmental clones were detected from denitrifying consortium and sediment samples, and 28 clones were assigned to either the bcr or the bzd type of benzoyl-CoA reductase genes. Thus, we could determine the genetic capabilities for anaerobic degradation of aromatic compounds in sediment communities of the Chesapeake Bay and the Arthur Kill on the basis of the detection of two types of benzoyl-CoA reductase genes. The detected genes have future applications as genetic markers to monitor aromatic compound degradation in natural and engineered ecosystems. PMID:15812036

  2. Coenzyme Q10 attenuated DMH-induced precancerous lesions in SD rats.

    PubMed

    Kim, Jung-Mi; Park, Eunju

    2010-01-01

    Coenzyme Q10 (CoQ10) is known to be a compound with mitochondrial bioenergetic functions and antioxidant activity. In this study, we evaluated the effect of CoQ10 on the formation of aberrant crypt foci (ACF) induced by 1,2-dimethylhydrazine (DMH), DMH-induced leukocytic DNA damage and gene expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by real-time PCR in colonic mucosa of male SD rats. The animals were divided into three groups and fed a casein-based high-fat and low fiber diet (100 g lard+20 g cellulose/kg diet) with or without CoQ10 (0.4 mg in soybean oil/kg BW/d, i.p.). One week after beginning the diets, the rats were subjected to 6 wk of treatment with DMH (30 mg/kg/wk, s.c.) and CoQ10 treatments continued over the entirety of the experimental period (59 d). Administration of CoQ10 resulted in reduction of ACF numbers, to 20% of the carcinogen control value. CoQ10 supplementation induced an antigenotoxic effect on DMH-induced DNA damage in the blood cells. Colonic mucosa of DMH-injected rats had significantly greater COX-2 and iNOS gene expression than those of control rats, while treatment with CoQ10 induced an inhibitory effect on over-expression of COX-2 and iNOS in colon tumors. Our results provide evidence that CoQ10 has a protective effect on the process of colon carcinogenesis, suppressing the development of preneoplastic lesions, possibly by modulating COX-2 and iNOS gene expression in colonic mucosa and DNA damage in leukocytes, suggesting that CoQ10 has chemotherapeutic activity.

  3. Coenzyme Q10, carotenoid, tocopherol, and retinol levels in cord plasma from multiethnic subjects in Hawaii.

    PubMed

    Franke, A A; Lai, J F; Morrison, C M; Pagano, I; Li, X; Halm, B M; Soon, R; Custer, L J

    2013-09-01

    Coenzyme Q10 (Q10), carotenoids, tocopherols, and retinol are the major circulating lipid-phase micronutrients (LPM) known to help mitigate oxidative damage and prevent chronic diseases. However, the functions of these compounds in newborns are little understood. This is due, in part, to the paucity of studies reporting their concentrations in this population. We measured Q10, carotenoids, tocopherols, and retinol in cord plasma from 100 multiethnic subjects living in Hawaii using HPLC with diode array and electrochemical detection. Appropriate internal standards were used including, for the first time, custom designed oxidized (UN10) and reduced (UL10) Q10 analogues. These compounds reflected the oxidation of UL10 to UN10 that occurred during sample processing and analysis and thus permitted accurate adjustments of natively circulating Q10 levels. All LPM measured were much lower in cord than in peripheral plasma. Cord plasma levels of total carotenoids, tocopherols, and retinol were approximately 10-fold, 3- to 5-fold and 1.5- to 3-fold lower than those in children or women. Cord plasma levels of total Q10 (TQ10; median, 113 ng/mL) were approximately 2-fold or 7- to 9-fold lower than peripheral plasma levels of neonates or children and adults, respectively. In contrast, the UN10/TQ10 ratio was substantially higher in cord (24%) than in peripheral plasma of children (3-4%) or adults (9%). Among the 5 ethnic groups in our cohort, no differences were observed in the levels of UN10, UL10, or TQ10. However, significant differences in many of the LPM were observed between ethnicities. More research is needed to explain these phenomena.

  4. Identification of Mitochondrial Coenzyme A Transporters from Maize and Arabidopsis1[W][OA

    PubMed Central

    Zallot, Rémi; Agrimi, Gennaro; Lerma-Ortiz, Claudia; Teresinski, Howard J.; Frelin, Océane; Ellens, Kenneth W.; Castegna, Alessandra; Russo, Annamaria; de Crécy-Lagard, Valérie; Mullen, Robert T.; Palmieri, Ferdinando; Hanson, Andrew D.

    2013-01-01

    Plants make coenzyme A (CoA) in the cytoplasm but use it for reactions in mitochondria, chloroplasts, and peroxisomes, implying that these organelles have CoA transporters. A plant peroxisomal CoA transporter is already known, but plant mitochondrial or chloroplastic CoA transporters are not. Mitochondrial CoA transporters belonging to the mitochondrial carrier family, however, have been identified in yeast (Saccharomyces cerevisiae; Leu-5p) and mammals (SLC25A42). Comparative genomic analysis indicated that angiosperms have two distinct homologs of these mitochondrial CoA transporters, whereas nonflowering plants have only one. The homologs from maize (Zea mays; GRMZM2G161299 and GRMZM2G420119) and Arabidopsis (Arabidopsis thaliana; At1g14560 and At4g26180) all complemented the growth defect of the yeast leu5Δ mitochondrial CoA carrier mutant and substantially restored its mitochondrial CoA level, confirming that these proteins have CoA transport activity. Dual-import assays with purified pea (Pisum sativum) mitochondria and chloroplasts, and subcellular localization of green fluorescent protein fusions in transiently transformed tobacco (Nicotiana tabacum) Bright Yellow-2 cells, showed that the maize and Arabidopsis proteins are targeted to mitochondria. Consistent with the ubiquitous importance of CoA, the maize and Arabidopsis mitochondrial CoA transporter genes are expressed at similar levels throughout the plant. These data show that representatives of both monocotyledons and eudicotyledons have twin, mitochondrially located mitochondrial carrier family carriers for CoA. The highly conserved nature of these carriers makes possible their reliable annotation in other angiosperm genomes. PMID:23590975

  5. Subcellular localization of Arabidopsis 3-hydroxy-3-methylglutaryl-coenzyme A reductase.

    PubMed

    Leivar, Pablo; González, Víctor M; Castel, Susanna; Trelease, Richard N; López-Iglesias, Carmen; Arró, Montserrat; Boronat, Albert; Campos, Narciso; Ferrer, Albert; Fernàndez-Busquets, Xavier

    2005-01-01

    Plants produce diverse isoprenoids, which are synthesized in plastids, mitochondria, endoplasmic reticulum (ER), and the nonorganellar cytoplasm. 3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR) catalyzes the synthesis of mevalonate, a rate-limiting step in the cytoplasmic pathway. Several branches of the pathway lead to the synthesis of structurally and functionally varied, yet essential, isoprenoids. Several HMGR isoforms have been identified in all plants examined. Studies based on gene expression and on fractionation of enzyme activity suggested that subcellular compartmentalization of HMGR is an important intracellular channeling mechanism for the production of the specific classes of isoprenoids. Plant HMGR has been shown previously to insert in vitro into the membrane of microsomal vesicles, but the final in vivo subcellular localization(s) remains controversial. To address the latter in Arabidopsis (Arabidopsis thaliana) cells, we conducted a multipronged microscopy and cell fractionation approach that included imaging of chimeric HMGR green fluorescent protein localizations in transiently transformed cell leaves, immunofluorescence confocal microscopy in wild-type and stably transformed seedlings, immunogold electron microscopy examinations of endogenous HMGR in seedling cotyledons, and sucrose density gradient analyses of HMGR-containing organelles. Taken together, the results reveal that endogenous Arabidopsis HMGR is localized at steady state within ER as expected, but surprisingly also predominantly within spherical, vesicular structures that range from 0.2- to 0.6-microm diameter, located in the cytoplasm and within the central vacuole in differentiated cotyledon cells. The N-terminal region, including the transmembrane domain of HMGR, was found to be necessary and sufficient for directing HMGR to ER and the spherical structures. It is believed, although not directly demonstrated, that these vesicle-like structures are derived from segments of

  6. Subcellular Localization of Arabidopsis 3-Hydroxy-3-Methylglutaryl-Coenzyme A Reductase1

    PubMed Central

    Leivar, Pablo; González, Víctor M.; Castel, Susanna; Trelease, Richard N.; López-Iglesias, Carmen; Arró, Montserrat; Boronat, Albert; Campos, Narciso; Ferrer, Albert; Fernàndez-Busquets, Xavier

    2005-01-01

    Plants produce diverse isoprenoids, which are synthesized in plastids, mitochondria, endoplasmic reticulum (ER), and the nonorganellar cytoplasm. 3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR) catalyzes the synthesis of mevalonate, a rate-limiting step in the cytoplasmic pathway. Several branches of the pathway lead to the synthesis of structurally and functionally varied, yet essential, isoprenoids. Several HMGR isoforms have been identified in all plants examined. Studies based on gene expression and on fractionation of enzyme activity suggested that subcellular compartmentalization of HMGR is an important intracellular channeling mechanism for the production of the specific classes of isoprenoids. Plant HMGR has been shown previously to insert in vitro into the membrane of microsomal vesicles, but the final in vivo subcellular localization(s) remains controversial. To address the latter in Arabidopsis (Arabidopsis thaliana) cells, we conducted a multipronged microscopy and cell fractionation approach that included imaging of chimeric HMGR green fluorescent protein localizations in transiently transformed cell leaves, immunofluorescence confocal microscopy in wild-type and stably transformed seedlings, immunogold electron microscopy examinations of endogenous HMGR in seedling cotyledons, and sucrose density gradient analyses of HMGR-containing organelles. Taken together, the results reveal that endogenous Arabidopsis HMGR is localized at steady state within ER as expected, but surprisingly also predominantly within spherical, vesicular structures that range from 0.2- to 0.6-μm diameter, located in the cytoplasm and within the central vacuole in differentiated cotyledon cells. The N-terminal region, including the transmembrane domain of HMGR, was found to be necessary and sufficient for directing HMGR to ER and the spherical structures. It is believed, although not directly demonstrated, that these vesicle-like structures are derived from segments of HMGR

  7. Promotion of growth by Coenzyme Q10 is linked to gene expression in C. elegans.

    PubMed

    Fischer, Alexandra; Niklowitz, Petra; Menke, Thomas; Döring, Frank

    2014-10-03

    Coenzyme Q (CoQ, ubiquinone) is an essential component of the respiratory chain, a cofactor of pyrimidine biosynthesis and acts as an antioxidant in extra mitochondrial membranes. More recently CoQ has been identified as a modulator of apoptosis, inflammation and gene expression. CoQ deficient Caenorhabditis elegans clk-1 mutants show several phenotypes including a delayed postembryonic growth. Using wild type and two clk-1 mutants, here we established an experimental set-up to study the consequences of endogenous CoQ deficiency or exogenous CoQ supply on gene expression and growth. We found that a deficiency of endogenous CoQ synthesis down-regulates a cluster of genes that are important for growth (i.e., RNA polymerase II, eukaryotic initiation factor) and up-regulates oxidation reactions (i.e., cytochrome P450, superoxide dismutase) and protein interactions (i.e., F-Box proteins). Exogenous CoQ supply partially restores the expression of these genes as well as the growth retardation of CoQ deficient clk-1 mutants. On the other hand exogenous CoQ supply does not alter the expression of a further sub-set of genes. These genes are involved in metabolism (i.e., succinate dehydrogenase complex), cell signalling or synthesis of lectins. Thus, our work provides a comprehensive overview of genes which can be modulated in their expression by endogenous or exogenous CoQ. As growth retardation in CoQ deficiency is linked to the gene expression profile we suggest that CoQ promotes growth via gene expression.

  8. Immunolocalization of acyl-coenzyme A:cholesterol O-acyltransferase in macrophages.

    PubMed

    Khelef, N; Buton, X; Beatini, N; Wang, H; Meiner, V; Chang, T Y; Farese, R V; Maxfield, F R; Tabas, I

    1998-05-01

    Macrophages in atherosclerotic lesions accumulate large amounts of cholesteryl-fatty acyl esters ("foam cell" formation) through the intracellular esterification of cholesterol by acyl-coenzyme A:cholesterol O-acyltransferase (ACAT). In this study, we sought to determine the subcellular localization of ACAT in macrophages. Using mouse peritoneal macrophages and immunofluorescence microscopy, we found that a major portion of ACAT was in a dense reticular cytoplasmic network and in the nuclear membrane that colocalized with the luminal endoplasmic reticulum marker protein-disulfide isomerase (PDI) and that was in a similar distribution as the membrane-bound endoplasmic reticulum marker ribophorin. Remarkably, another portion of the macrophage ACAT pattern did not overlap with PDI or ribophorin, but was found in as yet unidentified cytoplasmic structures that were juxtaposed to the nucleus. Compartments containing labeled beta-very low density lipoprotein, an atherogenic lipoprotein, did not overlap with the ACAT label, but rather were embedded in the dense reticular network of ACAT. Furthermore, cell-surface biotinylation experiments revealed that freshly harvested, non-attached macrophages, but not those attached to tissue culture dishes, contained approximately 10-15% of ACAT on the cell surface. In summary, ACAT was found in several sites in macrophages: a cytoplasmic reticular/nuclear membrane site that overlaps with PDI and ribophorin and has the characteristics of the endoplasmic reticulum, a perinuclear cytoplasmic site that does not overlap with PDI or ribophorin and may be another cytoplasmic structure or possibly a unique subcompartment of the endoplasmic reticulum, and a cell-surface site in non-attached macrophages. Understanding possible physiological differences of ACAT in these locations may reveal an important component of ACAT regulation and macrophage foam cell formation.

  9. nde1 deletion improves mitochondrial DNA maintenance in Saccharomyces cerevisiae coenzyme Q mutants.

    PubMed

    Gomes, Fernando; Tahara, Erich B; Busso, Cleverson; Kowaltowski, Alicia J; Barros, Mario H

    2013-02-01

    Saccharomyces cerevisiae has three distinct inner mitochondrial membrane NADH dehydrogenases mediating the transfer of electrons from NADH to CoQ (coenzyme Q): Nde1p, Nde2p and Ndi1p. The active site of Ndi1p faces the matrix side, whereas the enzymatic activities of Nde1p and Nde2p are restricted to the intermembrane space side, where they are responsible for cytosolic NADH oxidation. In the present study we genetically manipulated yeast strains in order to alter the redox state of CoQ and NADH dehydrogenases to evaluate the consequences on mtDNA (mitochondrial DNA) maintenance. Interestingly, nde1 deletion was protective for mtDNA in strains defective in CoQ function. Additionally, the absence of functional Nde1p promoted a decrease in the rate of H2O2 release in isolated mitochondria from different yeast strains. On the other hand, overexpression of the predominant NADH dehydrogenase NDE1 elevated the rate of mtDNA loss and was toxic to coq10 and coq4 mutants. Increased CoQ synthesis through COQ8 overexpression also demonstrated that there is a correlation between CoQ respiratory function and mtDNA loss: supraphysiological CoQ levels were protective against mtDNA loss in the presence of oxidative imbalance generated by Nde1p excess or exogenous H2O2. Altogether, our results indicate that impairment in the oxidation of cytosolic NADH by Nde1p is deleterious towards mitochondrial biogenesis due to an increase in reactive oxygen species release.

  10. Plasma Coenzyme Q10 Predicts Lipid-lowering Response to High-Dose Atorvastatin

    PubMed Central

    Pacanowski, Michael A.; Frye, Reginald F.; Enogieru, Osatohanmen; Schofield, Richard S.; Zineh, Issam

    2008-01-01

    Background Coenzyme Q10 (CoQ10) is a provitamin synthesized via the HMG-CoA reductase pathway, and thus may serve as a potential marker of intrinsic HMG-CoA reductase activity. HMG-CoA reductase inhibitors (statins) decrease CoQ10, although it is unclear whether this is due to reductions in lipoproteins, which transport CoQ10. Objectives We evaluated whether baseline plasma CoQ10 concentrations predict the lipid-lowering response to high-dose atorvastatin, and to what extent CoQ10 changes following atorvastatin therapy depend on lipoprotein changes. Methods Individuals without dyslipidemia or known cardiovascular disease (n=84) received atorvastatin 80 mg daily for 16 weeks. Blood samples collected at baseline and after 4, 8, and 16 weeks of treatment were assayed for CoQ10. Results Individuals with higher baseline CoQ10:LDL-C ratios displayed diminished absolute and percent LDL-C reductions at 8 and 16 weeks of atorvastatin treatment (P<0.001 to 0.01). After 16 weeks of atorvastatin, plasma CoQ10 decreased 45% from 762±301 ng/ml to 374±150 ng/ml (P<0.001). CoQ10 changes were correlated with LDL-C and apolipoprotein B changes (r=0.27-0.38, P=0.001-0.02), but remained significant when normalized to all lipoproteins. CoQ10 changes were not associated with adverse drug reactions. Conclusion Baseline CoQ10:LDL-C ratio was associated with the degree of LDL-C response to atorvastatin. Atorvastatin decreased CoQ10 concentrations in a manner that was not completely dependent on lipoprotein changes. The utility of CoQ10 as a predictor of atorvastatin response should be further explored in patients with dyslipidemia. PMID:19649137

  11. Dependence of mitochondrial coenzyme A uptake on the membrane electrical gradient

    SciTech Connect

    Tahiliani, A.G. )

    1989-11-05

    Coenzyme A (CoA) transport was studied in isolated rat heart mitochondria. Uptake of CoA was assayed by determining (3H)CoA associated with mitochondria under various conditions. Various oxidizable substrates including alpha-ketoglutarate, succinate, or malate stimulated CoA uptake. The membrane proton (delta pH) and electrical (delta psi) gradients, which dissipated with time in the absence of substrate, were maintained at their initial levels throughout the incubation in the presence of substrate. Addition of phosphate caused a concentration-dependent decrease of both delta pH and CoA uptake. Nigericin also dissipated the proton gradient and prevented CoA uptake. Valinomycin also prevented CoA uptake into mitochondria. Although the proton gradient was unaffected, the electrical gradient was completely abolished in the presence of valinomycin. Addition of 5 mM phosphate 10 min after the start of incubation prevented further uptake of CoA into mitochondria. A rapid dissipation of the proton gradient upon addition of phosphate was observed. Addition of nigericin or valinomycin 10 min after the start of incubation also resulted in no further uptake of CoA into with mitochondria; valinomycin caused an apparent efflux of CoA from mitochondria. Uptake was found to be sensitive to external pH displaying a pH optimum at pHext 8.0. Although nigericin significantly inhibited CoA uptake over the pHext range of 6.75-8, maximal transport was observed around pHext 8.0-8.25. Valinomycin, on the other hand, abolished transport over the entire pH range. The results suggest that mitochondrial CoA transport is determined by the membrane electrical gradient. The apparent dependence of CoA uptake on an intact membrane pH gradient is probably the result of modulation of CoA transport by matrix pH.

  12. Combination therapy with metformin and coenzyme Q10 in murine experimental autoimmune arthritis.

    PubMed

    Jhun, JooYeon; Lee, SeungHoon; Kim, Se-Young; Na, Hyun Sik; Kim, Eun-Kyung; Kim, Jae-Kyung; Jeong, Jeong-Hee; Park, Sung Hwan; Cho, Mi-La

    2016-01-01

    Metformin (Met) and coenzyme Q10 (CoQ10) are reported to have therapeutic functions in several inflammatory diseases. These drugs have shown anti-inflammatory effects and have been utilized in mouse models of rheumatoid arthritis (RA). However, there is no evidence of the additive effect of Met and CoQ10 in RA. Although Met and CoQ10 may be involved in the improvement of mitochondrial dysfunction, limited information is available regarding whether this effect can improve mitochondrial dysfunction in RA in particular. In this study, we sought to determine whether Met and CoQ10 attenuate the severity of collagen-induced arthritis (CIA) and show an additive effect in a mouse model. The combination of Met and CoQ10 improved CIA, reducing joint inflammation, Th17 differentiation and IgG production. In contrast, the combination of Met and CoQ10 induced Treg differentiation. Osteoclastogenesis was reduced by the combination of Met and CoQ10. The protein expression of interleukin-1β, interleukin-6 and tumor necrosis factor-alpha in mice splenocytes exposed to lipopolysaccharide decreased after drug combination therapy. We also found that the expression of JC-1 and COX IV were enhanced by treatment with the combination of Met and CoQ10. Moreover, the combination of Met and CoQ10 promoted mitochondrial O2 consumption. These findings suggest that the combination of Met and CoQ10 reduced CIA severity, improving mitochondrial dysfunction compared to Met or CoQ10 alone. These results present a novel, significant preventive targets in RA and may enhance our understanding of its pathogenesis.

  13. Inhibition of Coenzyme Qs Accumulation in Engineered Escherichia coli by High Concentration of Farnesyl Diphosphate

    PubMed Central

    Samoudi, Mojtaba; Omid Yeganeh, Negar; Shahbani Zahiri, Hossein; Shariati, Parvin; Hajhosseini, Reza

    2015-01-01

    Background: Coenzyme Q 10 (CoQ 10 ) is an isoprenoid component used widely in nutraceutical industries. Farnesyl diphosphate synthase (FPPS) is a responsible enzyme for biosynthesis of farnesyl diphosphate (FPP), a key precursor for CoQs production. This research involved investigating the effect of FPPS over-expression on CoQs production in engineered CoQ 10 -producing Escherichia coli (E. coli). Methods: Two CoQ 10 -producing strains, as referred to E. coli Ba and E. coli Br, were transformed by the encoding gene for FPPS (ispA) under the control of either the trc or P BAD promoters. Results: Over-expression of ispA under the control of P BAD promoter led to a relative increase in CoQ 10 production only in recombinant E. coli Br although induction by arabinose resulted in partial reduction of CoQ 10 production in both recombinant E. coli Ba and E. coli Br strains. Over-expression of ispA under the control of stronger trc promoter, however, led to a severe decrease in CoQ 10 production in both recombinant E. coli Ba and E. coli Br strains, as reflected by reductions from 629±40 to 30±13 and 564±28 to 80±14 μg/g Dried Cell Weight (DCW), respectively. The results showed high level of FPP reduces endogenous CoQ 8 production as well and that CoQs are produced in a complimentary manner, as the increase in production of one decreases the production of the other. Conclusion: The reduction in CoQ 10 production can be a result of Dds inhibition by high FPP concentration. Therefore, more effort is needed to verify the role of intermediate metabolite concentration and to optimize production of CoQ 10 . PMID:26306151

  14. Coenzyme Q10 ameliorates oxidative stress and prevents mitochondrial alteration in ischemic retinal injury.

    PubMed

    Lee, Dongwook; Kim, Keun-Young; Shim, Myoung Sup; Kim, Sang Yeop; Ellisman, Mark H; Weinreb, Robert N; Ju, Won-Kyu

    2014-04-01

    Coenzyme Q10 (CoQ10) acts by scavenging reactive oxygen species for protecting neuronal cells against oxidative stress in neurodegenerative diseases. We tested whether a diet supplemented with CoQ10 ameliorates oxidative stress and mitochondrial alteration, as well as promotes retinal ganglion cell (RGC) survival in ischemic retina induced by intraocular pressure elevation. A CoQ10 significantly promoted RGC survival at 2 weeks after ischemia. Superoxide dismutase 2 (SOD2) and heme oxygenase-1 (HO-1) expression were significantly increased at 12 h after ischemic injury. In contrast, the CoQ10 significantly prevented the upregulation of SOD2 and HO-1 protein expression in ischemic retina. In addition, the CoQ10 significantly blocked activation of astroglial and microglial cells in ischemic retina. Interestingly, the CoQ10 blocked apoptosis by decreasing caspase-3 protein expression in ischemic retina. Bax and phosphorylated Bad (pBad) protein expression were significantly increased in ischemic retina at 12 h. Interestingly, while CoQ10 significantly decreased Bax protein expression in ischemic retina, CoQ10 showed greater increase of pBad protein expression. Of interest, ischemic injury significantly increased mitochondrial transcription factor A (Tfam) protein expression in the retina at 12 h, however, CoQ10 significantly preserved Tfam protein expression in ischemic retina. Interestingly, there were no differences in mitochondrial DNA content among control- or CoQ10-treated groups. Our findings demonstrate that CoQ10 protects RGCs against oxidative stress by modulating the Bax/Bad-mediated mitochondrial apoptotic pathway as well as prevents mitochondrial alteration by preserving Tfam protein expression in ischemic retina. Our results suggest that CoQ10 may provide neuroprotection against oxidative stress-mediated mitochondrial alterations in ischemic retinal injury.

  15. Stability and bioequivalence studies of two marketed formulations of coenzyme Q10 in beagle dogs.

    PubMed

    Kommuru, T R; Ashraf, M; Khan, M A; Reddy, I K

    1999-07-01

    Coenzyme Q10 (CoQ10), a highly lipophilic compound present in the inner mitochondrial membrane, is essential for production of cellular energy in the form of ATP. CoQ10 is used as an antioxidant and also in the treatment of various cardiovascular disorders. The relative bioavailabilities of powder filled capsule (I) and oil-based formulation (II) of CoQ10 were compared in beagle dogs in an open, randomized, multiple dose, cross-over design. Poor and slow absorption characteristics were observed for both the formulations. The AUC, Cmax, and Tmax for formulation I and II are comparable (p < 0.05) where the values for formulation I are 22.84 +/- 6.3 micrograms ml-1 h, 0.51 +/- 0.11 microgram/ml, and 6.1 +/- 2.0 h whereas the values for formulation II are 24.32 +/- 5.6 micrograms ml-1 h, 0.55 +/- 0.16 microgram/ml, and 6.6 +/- 2.3 h, respectively. Stability of CoQ10 at various temperature and humidity conditions and its photostability were studied. Various antioxidants were evaluated to determine the type and amount of antioxidant(s) required to improve the stability of CoQ10. Large extent of degradation was observed at 45 degrees C and 55 degrees C. The effect of humidity conditions on degradation was insignificant. Among the various antioxidants studied, mixture of ascorbic acid (5%) and EDTA (0.1%) offered better protection than phenolic antioxidants such as butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), or propyl gallate (PG). Further, increasing concentrations of phenolic antioxidants (from 0.1 to 0.3%) accelerated the degradation.

  16. [Overexpression, homology modeling and coenzyme docking studies of the cytochrome P450nor2 from Cylindrocarpon tonkinense].

    PubMed

    Li, N; Zhang, Y Z; Li, D D; Niu, Y H; Liu, J; Li, S X; Yuan, Y Z; Chen, S L; Geng, H; Liu, D L

    2016-01-01

    Cytochrome P450nor catalyzes an unusual reaction that transfers electrons from NADP/NADPH to bound heme directly. To improve the expression level of P450nor2 from Cylindrocarpon tonkinense (C.P450nor2), Escherichia coli system was utilized to substitute the yeast system we constructed for expression of the P450nor2 gene, and the protein was purified in soluble form using Ni(+)-NTA affinity chromatography. In contrast to P450nor from Fusarium oxysporum (F.P450nor) and P450nor1 from Cylindrocarpon tonkinense (C.P450nor1), C.P450nor2 shows a dual specificity for using NADH or NADPH as electron donors. The present study developed a computational approach in order to illustrate the coenzyme specificity of C.P450nor2 for NADH and NADPH. This study involved homology modeling of C.P450nor2 and docking analyses of NADH and NADPH into the crystal structure of F.P450nor and the predictive model of C.P450nor2, respectively. The results suggested that C.P450nor2 and F.P450nor have different coenzyme specificity for NADH and NADPH; whilst the space around the B'-helix of the C.P450nor2, especially the Ser79 and Gly81, play a crucial role for the specificity of C.P450nor2. In the absence of the experimental structure of C.P450nor2, we hope that our model will be useful to provide rational explanation on coenzyme specificity of C.P450nor2.

  17. Identification of structurally diverse methanofuran coenzymes in methanococcales that are both N-formylated and N-acetylated.

    PubMed

    Allen, Kylie D; White, Robert H

    2014-10-07

    Methanofuran (MF) is a coenzyme necessary for the first step of methanogenesis from CO2. The well-characterized MF core structure is 4-[N-(γ-l-glutamyl-γ-l-glutamyl)-p-(β-aminoethyl)phenoxymethyl]-2-(aminomethyl)furan (APMF-γ-Glu2). Three different MF structures that differ on the basis of the composition of their side chains have been determined previously. Here, we use liquid chromatography coupled with high-resolution mass spectrometry and a variety of biochemical methods to deduce the unique structures of MFs present in four different methanogens in the order Methanococcales. This is the first detailed characterization of the MF occurring in methanogens of this order. MF in each of these organisms contains the expected APMF-γ-Glu2; however, the composition of the side chain is different from that of the previously described MF structures. In Methanocaldococcus jannaschii, additional γ-linked glutamates that range from 7 to 12 residues are present. The MF coenzymes in Methanococcus maripaludis, Methanococcus vannielii, and Methanothermococcus okinawensis also have additional glutamate residues but interestingly also contain a completely different chemical moiety in the middle of the side chain that we have identified as N-(3-carboxy-2- or 3-hydroxy-1-oxopropyl)-l-aspartic acid. This addition results in the terminal γ-linked glutamates being incorporated in the opposite orientation. In addition to these nonacylated MF coenzymes, we also identified the corresponding N-formyl-MF and, surprisingly, N-acetyl-MF derivatives. N-Acetyl-MF has never been observed or implied to be functioning in nature and may represent a new route for acetate formation in methanogens.

  18. Protection of dichlorvos induced oxidative stress and nigrostriatal neuronal death by chronic Coenzyme Q{sub 10} pretreatment

    SciTech Connect

    Binukumar, BK; Gupta, Nidhi; Bal, Amanjit; Gill, Kiran Dip

    2011-10-01

    Numerous epidemiological studies have shown an association between pesticide exposure and increased risk of developing Parkinson's diseases. Oxidative stress generated as a result of mitochondrial dysfunction has been implicated as an important factor in the etiology of Parkinson's disease. Previously, we reported that chronic dichlorvos exposure causes mitochondrial impairments and nigrostriatal neuronal death in rats. The present study was designed to test whether Coenzyme Q{sub 10} (CoQ{sub 10}) administration has any neuroprotective effect against dichlorvos mediated nigrostriatal neuronal death, {alpha}-synuclein aggregation, and motor dysfunction. Male albino rats were administered dichlorvos by subcutaneous injection at a dose of 2.5 mg/kg body weight over a period of 12 weeks. Results obtained there after showed that dichlorvos exposure leads to enhanced mitochondrial ROS production, {alpha}-synuclein aggregation, decreased dopamine and its metabolite levels resulting in nigrostriatal neurodegeneration. Pretreatment by Coenzyme Q{sub 10} (4.5 mg/kg ip for 12 weeks) to dichlorvos treated animals significantly attenuated the extent of nigrostriatal neuronal damage, in terms of decreased ROS production, increased dopamine and its metabolite levels, and restoration of motor dysfunction when compared to dichlorvos treated animals. Thus, the present study shows that Coenzyme Q{sub 10} administration may attenuate dichlorvos induced nigrostriatal neurodegeneration, {alpha}-synuclein aggregation and motor dysfunction by virtue of its antioxidant action. - Highlights: > CoQ{sub 10} administration attenuates dichlorvos induced nigrostriatal neurodegenaration. > CoQ{sub 10} pre treatment leads to preservation of TH-IR neurons. > CoQ{sub 10} may decrease oxidative damage and {alpha}-synuclin aggregation. > CoQ{sub 10} treatment enhances motor function and protects rats from catalepsy.

  19. Recovery of the Frank-Starling mechanism by coenzyme Q10 in patients with load-induced contractility depression.

    PubMed

    Oda, T

    1993-01-01

    Load-induced contractility depression, in which supernormal left ventricular ejection fraction and contractility at rest decrease by added afterload, is most often found in children with mitral valve prolapse who have symptoms. Patients have high ventricular end-diastolic pressure at rest, which is further increased by afterload challenge. The Frank-Starling mechanism may be maximally mobilized with high preload even at rest to compensate for the intrinsically depressed inotropic state. Therefore, preload reserve may be easily exhausted due to afterload addition. We aimed to determine left ventricular end-diastolic fiber length, stroke work, and contractility before and during handgrip by echocardiograms to obtain evidence for the Frank-Starling mechanism in patients and controls, including patients treated with coenzyme Q10. The subjects were divided into four groups, each consisting of 30 children aged 6-16 years: group 1, normals; group 2, patients; group 3, the same patients as in group 2 after coenzyme Q10 therapy; and group 4, patients with asymptomatic mitral valve prolapse. Baseline values and percentage increases in systolic blood pressure, heart rate, and left ventricular wall stress showed no differences among the groups. Only in group 2 were the percentage increase in ejection fraction, fiber shortening velocity, contractility, and end-diastolic dimension strongly negative, despite supernormal baseline levels. In other groups, these were significantly positive, without intergroup differences. We conclude that in the heart with load-induced contractility depression, the Frank-Starling mechanism deviates from normal. The normal Frank-Starling mechanism was recovered due to coenzyme Q10, which may improve disturbed bioenergetic function at the molecular level.

  20. Methyl-coenzyme M reductase from methanogenic archaea: isotope effects on the formation and anaerobic oxidation of methane.

    PubMed

    Scheller, Silvan; Goenrich, Meike; Thauer, Rudolf K; Jaun, Bernhard

    2013-10-09

    The nickel enzyme methyl-coenzyme M reductase (MCR) catalyzes two important transformations in the global carbon cycle: methane formation and its reverse, the anaerobic oxidation of methane. MCR uses the methyl thioether methyl-coenzyme M (CH3-S-CH2CH2-SO3(-), Me-S-CoM) and the thiol coenzyme B (CoB-SH) as substrates and converts them reversibly to methane and the corresponding heterodisulfide (CoB-S-S-CoM). The catalytic mechanism is still unknown. Here, we present isotope effects for this reaction in both directions, catalyzed by the enzyme isolated from Methanothermobacter marburgensis . For methane formation, a carbon isotope effect ((12)CH3-S-CoM/(13)CH3-S-CoM) of 1.04 ± 0.01 was measured, showing that breaking of the C-S bond in the substrate Me-S-CoM is the rate-limiting step. A secondary isotope effect of 1.19 ± 0.01 per D in the methyl group of CD3-S-CoM indicates a geometric change of the methyl group from tetrahedral to trigonal planar upon going to the transition state of the rate-limiting step. This finding is consistent with an almost free methyl radical in the highest transition state. Methane activation proceeds with a primary isotope effect of 2.44 ± 0.22 for the C-H vs C-D bond breakage and a secondary isotope effect corresponding to 1.17 ± 0.05 per D. These values are consistent with isotope effects reported for oxidative cleavage/reductive coupling occurring at transition metal centers during C-H activation but are also in the range expected for the radical substitution mechanism proposed by Siegbahn et al. The isotope effects presented here constitute boundary conditions for any suggested or calculated mechanism.

  1. Arg279 is the key regulator of coenzyme selectivity in the flavin-dependent ornithine monooxygenase SidA.

    PubMed

    Robinson, Reeder; Franceschini, Stefano; Fedkenheuer, Michael; Rodriguez, Pedro J; Ellerbrock, Jacob; Romero, Elvira; Echandi, Maria Paulina; Martin Del Campo, Julia S; Sobrado, Pablo

    2014-04-01

    Siderophore A (SidA) is a flavin-dependent monooxygenase that catalyzes the NAD(P)H- and oxygen-dependent hydroxylation of ornithine in the biosynthesis of siderophores in Aspergillus fumigatus and is essential for virulence. SidA can utilize both NADPH or NADH for activity; however, the enzyme is selective for NADPH. Structural analysis shows that R279 interacts with the 2'-phosphate of NADPH. To probe the role of electrostatic interactions in coenzyme selectivity, R279 was mutated to both an alanine and a glutamate. The mutant proteins were active but highly uncoupled, oxidizing NADPH and producing hydrogen peroxide instead of hydroxylated ornithine. For wtSidA, the catalytic efficiency was 6-fold higher with NADPH as compared to NADH. For the R279A mutant the catalytic efficiency was the same with both coenyzmes, while for the R279E mutant the catalytic efficiency was 5-fold higher with NADH. The effects are mainly due to an increase in the KD values, as no major changes on the kcat or flavin reduction values were observed. Thus, the absence of a positive charge leads to no coenzyme selectivity while introduction of a negative charge leads to preference for NADH. Flavin fluorescence studies suggest altered interaction between the flavin and NADP⁺ in the mutant enzymes. The effects are caused by different binding modes of the coenzyme upon removal of the positive charge at position 279, as no major conformational changes were observed in the structure for R279A. The results indicate that the positive charge at position 279 is critical for tight binding of NADPH and efficient hydroxylation.

  2. Effect of pre- and post-combined multidoses of epigallocatechin gallate and coenzyme Q10 on cisplatin-induced oxidative stress in rat kidney.

    PubMed

    Fatima, Sabiha; Al-Mohaimeed, Noura; Arjumand, Sadia; Banu, Naheed; Al-Jameil, Noura; Al-Shaikh, Yazeed

    2015-02-01

    The nephroprotective effect of coenzyme Q10 and epigallocatechin gallate was investigated in rats with acute renal injury induced by a single nephrotoxic dose of cisplatin. Two days prior to cisplatin administration, epigallocatechin gallate and coenzyme Q10 alone and in four different combinations were given for 6 days. The treatment with antioxidants significantly protected the cisplatin-induced increase in the levels of blood urea nitrogen and serum creatinine. Both the antioxidants alone or in different combinations significantly compensated the increased malondialdehyde and reduced glutathione levels. Moreover, the decrease in the activities of superoxide dismutase, catalase, and glutathione peroxidase and the concentration of selenium, zinc, and copper ions were significantly attenuated in renal tissue. In conclusion, epigallocatechin gallate and coenzyme Q10 are equally effective against cisplatin-induced nephrotoxicity, whereas the intervention by combining these two antioxidants was found to be highly effective at low doses in attenuating oxidative stress in rat kidney.

  3. Coenzyme Q10 protects renal proximal tubule cells against nicotine-induced apoptosis through induction of p66(shc)-dependent antioxidant responses.

    PubMed

    Arany, Istvan; Carter, Anthony; Hall, Samuel; Fulop, Tibor; Dixit, Mehul

    2017-02-01

    Chronic nicotine exposure (via smoking, E-cigarettes) increases oxidative stress in the kidney that sensitizes it to additional injury in experimental models and in the renal patient. The pro-apoptotic p66(shc) protein-via serine36 phosphorylation that facilitates its mitochondrial translocation and therein cytochrome c binding-generates oxidative stress that leads to injury of renal proximal tubule cells during chronic nicotine exposure. Coenzyme Q10-a clinically safe antioxidant-has been used against nicotine/smoke extract-associated oxidative stress in various non-renal cells. This study explored the anti-oxidant/anti-apoptotic effect of Coenzyme Q10 on nicotine-induced oxidative stress and its impact on p66shc in cultured rat renal proximal tubule cells (NRK52E). We studied the anti-oxidant effect of 10 µM Coenzyme Q10 using various mutants of the p66shc gene and also determined the induction of selected anti-oxidant entities (antioxidant response element, promoter of the manganese superoxide dismutase gene) in reporter luciferase assay during oxidative stress induced by 200 µM nicotine. Our studies revealed that Coenzyme Q10 strongly inhibits nicotine-mediated production of reactive oxygen species and consequent apoptosis that requires serine36 phosphorylation but not mitochondrial translocation/cytochrome c binding of p66(shc). While both nicotine and Coenzyme Q10 stimulates the p66shc promoter, only nicotine exposure results in mitochondrial translocation of p66(shc). In contrast, the Coenzyme Q10-stimulated and non-mitochondrial p66(shc) activates the anti-oxidant manganese superoxide dismutase promoter via the antioxidant response elements and hence, rescues cells from nicotine-induced oxidative stress and consequent apoptosis.

  4. Actinobacterial Acyl Coenzyme A Synthetases Involved in Steroid Side-Chain Catabolism

    PubMed Central

    Casabon, Israël; Swain, Kendra; Crowe, Adam M.

    2014-01-01

    Bacterial steroid catabolism is an important component of the global carbon cycle and has applications in drug synthesis. Pathways for this catabolism involve multiple acyl coenzyme A (CoA) synthetases, which activate alkanoate substituents for β-oxidation. The functions of these synthetases are poorly understood. We enzymatically characterized four distinct acyl-CoA synthetases from the cholate catabolic pathway of Rhodococcus jostii RHA1 and the cholesterol catabolic pathway of Mycobacterium tuberculosis. Phylogenetic analysis of 70 acyl-CoA synthetases predicted to be involved in steroid metabolism revealed that the characterized synthetases each represent an orthologous class with a distinct function in steroid side-chain degradation. The synthetases were specific for the length of alkanoate substituent. FadD19 from M. tuberculosis H37Rv (FadD19Mtb) transformed 3-oxo-4-cholesten-26-oate (kcat/Km = 0.33 × 105 ± 0.03 × 105 M−1 s−1) and represents orthologs that activate the C8 side chain of cholesterol. Both CasGRHA1 and FadD17Mtb are steroid-24-oyl-CoA synthetases. CasG and its orthologs activate the C5 side chain of cholate, while FadD17 and its orthologs appear to activate the C5 side chain of one or more cholesterol metabolites. CasIRHA1 is a steroid-22-oyl-CoA synthetase, representing orthologs that activate metabolites with a C3 side chain, which accumulate during cholate catabolism. CasI had similar apparent specificities for substrates with intact or extensively degraded steroid nuclei, exemplified by 3-oxo-23,24-bisnorchol-4-en-22-oate and 1β(2′-propanoate)-3aα-H-4α(3″-propanoate)-7aβ-methylhexahydro-5-indanone (kcat/Km = 2.4 × 105 ± 0.1 × 105 M−1 s−1 and 3.2 × 105 ± 0.3 × 105 M−1 s−1, respectively). Acyl-CoA synthetase classes involved in cholate catabolism were found in both Actinobacteria and Proteobacteria. Overall, this study provides insight into the physiological roles of acyl-CoA synthetases in steroid catabolism and

  5. Altering coenzyme specificity of Pichia stipitis xylose reductase by the semi-rational approach CASTing

    PubMed Central

    Liang, Ling; Zhang, Jingqing; Lin, Zhanglin

    2007-01-01

    Background The NAD(P)H-dependent Pichia stipitis xylose reductase (PsXR) is one of the key enzymes for xylose fermentation, and has been cloned into the commonly used ethanol-producing yeast Saccharomyces cerevisiae. In order to eliminate the redox imbalance resulting from the preference of this enzyme toward NADPH, efforts have been made to alter the coenzyme specificity of PsXR by site-directed mutagenesis, with limited success. Given the industrial importance of PsXR, it is of interest to investigate further ways to create mutants of PsXR that prefers NADH rather than NADPH, by the alternative directed evolution approach. Results Based on a homology model of PsXR, six residues were predicted to interact with the adenine ribose of NAD(P)H in PsXR and altered using a semi-rational mutagenesis approach (CASTing). Three rounds of saturation mutagenesis were carried to randomize these residues, and a microplate-based assay was applied in the screening. A best mutant 2-2C12, which carried four mutations K270S, N272P, S271G and R276F, was obtained. The mutant showed a preference toward NADH over NADPH by a factor of about 13-fold, or an improvement of about 42-fold, as measured by the ratio of the specificity constant kcat/Kmcoenzyme. Compared with the wild-type, the kcatNADH for the best mutant was only slightly lower, while the kcatNADPH decreased by a factor of about 10. Furthermore, the specific activity of 2-2C12 in the presence of NADH was 20.6 U·mg-1, which is highest among PsXR mutants reported. Conclusion A seemingly simplistic and yet very effective mutagenesis approach, CASTing, was applied successfully to alter the NAD(P)H preference for Pichia stipitis xylose reductase, an important enzyme for xylose-fermenting yeast. The observed change in the NAD(P)H preference for this enzyme seems to have resulted from the altered active site that is more unfavorable for NADPH than NADH in terms of both Km and kcat. There are potentials for application of our PsXR in

  6. The glmS ribozyme: use of a small molecule coenzyme by a gene-regulatory RNA.

    PubMed

    Ferré-D'Amaré, Adrian R

    2010-11-01

    The glmS ribozyme is the first known example of a natural ribozyme that has evolved to require binding of an exogenous small molecule for activity. In Gram-positive bacteria, this RNA domain is part of the messenger RNA (mRNA) encoding the essential enzyme that synthesizes glucosamine-6-phosphate (GlcN6P). When present at physiologic concentration, this small molecule binds to the glmS ribozyme and uncovers a latent self-cleavage activity that ultimately leads to degradation of the mRNA. Biochemical and structural studies reveal that the RNA adopts a rigid fold stabilized by three pseudoknots and the packing of a peripheral domain against the ribozyme core. GlcN6P binding to this pre-organized RNA does not induce conformational changes; rather, the small molecule functions as a coenzyme, providing a catalytically essential amine group to the active site. The ribozyme is not a passive player, however. Active site functional groups are essential for catalysis, even in the presence of GlcN6P. In addition to being a superb experimental system with which to analyze how RNA catalysts can exploit small molecule coenzymes to broaden their chemical versatility, the presence of the glmS ribozyme in numerous pathogenic bacteria make this RNA an attractive target for the development of new antibiotics and antibacterial strategies.

  7. Involvement of tristetraprolin in transcriptional activation of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase by insulin

    SciTech Connect

    Ness, Gene C.; Edelman, Jeffrey L.; Brooks, Patricia A.

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer siRNAs to tristetraprolin blocks transcription of HMGR in vivo in rat liver. Black-Right-Pointing-Pointer siRNAs to tristetraprolin inhibits insulin activation of HMGR transcription. Black-Right-Pointing-Pointer Insulin acts to rapidly increase tristetraprolin in liver nuclear extracts. -- Abstract: Several AU-rich RNA binding element (ARE) proteins were investigated for their possible effects on transcription of hepatic 3-hydroxy-3-methyglutaryl coenzyme A reductase (HMGR) in normal rats. Using in vivo electroporation, four different siRNAs to each ARE protein were introduced together with HMGR promoter (-325 to +20) luciferase construct and compared to saline controls. All four siRNAs to tristetraprolin (TTP) completely eliminated transcription from the HMGR promoter construct. Since insulin acts to rapidly increase hepatic HMGR transcription, the effect of TTP siRNA on induction by insulin was tested. The 3-fold stimulation by insulin was eliminated by this treatment. In comparison, siRNA to AU RNA binding protein/enoyl coenzyme A hydratase (AUH) had no effect. These findings indicate a role for TTP in the insulin-mediated activation of hepatic HMGR transcription.

  8. Potential role of acyl-coenzyme A:cholesterol transferase (ACAT) Inhibitors as hypolipidemic and antiatherosclerosis drugs.

    PubMed

    Leon, Carlos; Hill, John S; Wasan, Kishor M

    2005-10-01

    Acyl-coenzyme A:cholesterol transferase (ACAT) is an integral membrane protein localized in the endoplasmic reticulum. ACAT catalyzes the formation of cholesteryl esters from cholesterol and fatty acyl coenzyme A. The cholesteryl esters are stored as cytoplasmic lipid droplets inside the cell. This process is very important to the organism as high cholesterol levels have been associated with cardiovascular disease. In mammals, two ACAT genes have been identified, ACAT1 and ACAT2. ACAT1 is ubiquitous and is responsible for cholesteryl ester formation in brain, adrenal glands, macrophages, and kidneys. ACAT2 is expressed in the liver and intestine. The inhibition of ACAT activity has been associated with decreased plasma cholesterol levels by suppressing cholesterol absorption and by diminishing the assembly and secretion of apolipoprotein B-containing lipoproteins such as very low density lipoprotein (VLDL). ACAT inhibition also prevents the conversion of macrophages into foam cells in the arterial walls, a critical event in the development of atherosclerosis. This review paper will focus on the role of ACAT in cholesterol metabolism, in particular as a target to develop novel therapeutic agents to control hypercholesterolemia, atherosclerosis, and Alzheimer's disease.

  9. Mitochondrial dysfunction in obesity: potential benefit and mechanism of Co-enzyme Q10 supplementation in metabolic syndrome

    PubMed Central

    2014-01-01

    Co-enzyme Q10 (Co-Q10) is an essential component of the mitochondrial electron transport chain. Most cells are sensitive to co-enzyme Q10 (Co-Q10) deficiency. This deficiency has been implicated in several clinical disorders such as heart failure, hypertension, Parkinson’s disease and obesity. The lipid lowering drug statin inhibits conversion of HMG-CoA to mevalonate and lowers plasma Co-Q10 concentrations. However, supplementation with Co-Q10 improves the pathophysiological condition of statin therapy. Recent evidence suggests that Co-Q10 supplementation may be useful for the treatment of obesity, oxidative stress and the inflammatory process in metabolic syndrome. The anti-inflammatory response and lipid metabolizing effect of Co-Q10 is probably mediated by transcriptional regulation of inflammation and lipid metabolism. This paper reviews the evidence showing beneficial role of Co-Q10 supplementation and its potential mechanism of action on contributing factors of metabolic and cardiovascular complications. PMID:24932457

  10. Mitochondrial dysfunction in obesity: potential benefit and mechanism of Co-enzyme Q10 supplementation in metabolic syndrome.

    PubMed

    Alam, Md Ashraful; Rahman, Md Mahbubur

    2014-01-01

    Co-enzyme Q10 (Co-Q10) is an essential component of the mitochondrial electron transport chain. Most cells are sensitive to co-enzyme Q10 (Co-Q10) deficiency. This deficiency has been implicated in several clinical disorders such as heart failure, hypertension, Parkinson's disease and obesity. The lipid lowering drug statin inhibits conversion of HMG-CoA to mevalonate and lowers plasma Co-Q10 concentrations. However, supplementation with Co-Q10 improves the pathophysiological condition of statin therapy. Recent evidence suggests that Co-Q10 supplementation may be useful for the treatment of obesity, oxidative stress and the inflammatory process in metabolic syndrome. The anti-inflammatory response and lipid metabolizing effect of Co-Q10 is probably mediated by transcriptional regulation of inflammation and lipid metabolism. This paper reviews the evidence showing beneficial role of Co-Q10 supplementation and its potential mechanism of action on contributing factors of metabolic and cardiovascular complications.

  11. Kinetic characterization of the inhibition of acyl coenzyme A: steroid acyltransferases by tributyltin in the eastern mud snail (Ilyanassa obsoleta).

    PubMed

    Sternberg, Robin M; LeBlanc, Gerald A

    2006-06-30

    Exposure to tributyltin (TBT) has been causally associated with the global occurrence of a pseudohermaphroditic condition called imposex in neogastropod species. TBT elevates free testosterone levels in these organisms, and this upsurge in testosterone may be involved in the development of imposex. We investigated the ability of TBT to inhibit acyl coenzyme A:testosterone acyltransferase (ATAT) activity as well as microsomal acyl-coenzyme A:17beta-estradiol acyltransferase (AEAT) in a neogastropod, the eastern mud snail Ilyanassa obsoleta as a mechanism by which TBT elevates free testosterone. TBT significantly inhibited both ATAT and AEAT activities in vitro at toxicologically relevant in vivo concentrations. Kinetic analyses revealed that TBT is a competitive inhibitor of ATAT (K(i)= approximately 9microM) and is a weaker, noncompetitive inhibitor of AEAT (K(i)= approximately 31microM). ATAT and AEAT activities associated with different microsome preparations were significantly correlated, and 17beta-estradiol competitively inhibited the fatty acid esterification of testosterone suggesting that one enzyme is responsible for biotransforming both testosterone and 17beta-estradiol to their corresponding fatty acid esters. Overall, the results of this study supply the much-needed mechanistic support for the hypothesis that TBT elevates free testosterone in neogastropods by inhibiting their major regulatory process for maintaining free testosterone homeostasis-the fatty acid esterification of testosterone.

  12. Coenzyme Q Biosynthesis: Evidence for a Substrate Access Channel in the FAD-Dependent Monooxygenase Coq6

    PubMed Central

    Ismail, Alexandre; Leroux, Vincent; Smadja, Myriam; Gonzalez, Lucie; Lombard, Murielle; Pierrel, Fabien; Mellot-Draznieks, Caroline; Fontecave, Marc

    2016-01-01

    Coq6 is an enzyme involved in the biosynthesis of coenzyme Q, a polyisoprenylated benzoquinone lipid essential to the function of the mitochondrial respiratory chain. In the yeast Saccharomyces cerevisiae, this putative flavin-dependent monooxygenase is proposed to hydroxylate the benzene ring of coenzyme Q (ubiquinone) precursor at position C5. We show here through biochemical studies that Coq6 is a flavoprotein using FAD as a cofactor. Homology models of the Coq6-FAD complex are constructed and studied through molecular dynamics and substrate docking calculations of 3-hexaprenyl-4-hydroxyphenol (4-HP6), a bulky hydrophobic model substrate. We identify a putative access channel for Coq6 in a wild type model and propose in silico mutations positioned at its entrance capable of partially (G248R and L382E single mutations) or completely (a G248R-L382E double-mutation) blocking access to the channel for the substrate. Further in vivo assays support the computational predictions, thus explaining the decreased activities or inactivation of the mutated enzymes. This work provides the first detailed structural information of an important and highly conserved enzyme of ubiquinone biosynthesis. PMID:26808124

  13. Studies on the "Aerobic" Acetyl-Coenzyme A Synthetase of Saccharomyces Cerevisiae: Purification, Crystallization, and Physical Properties of the Enzyme

    NASA Technical Reports Server (NTRS)

    Satyanarayana, T.; Klein, Harold P.

    1976-01-01

    A procedure for the purification of a stable acetyl-coenzyme A synthetase (ACS) from aerobic cells of Saccharomyces cerevisiae is presented. The steps include differential centrifugation, solubilization of the bound enzyme from the crude mitochondrial fraction, ammonium sulfate fractionation, crystallization to constant specific activity from ammonium sulfate solutions followed by Bio-Gel A-1.5 m column chromatography. The resulting enzyme preparation is homogeneous as judged by chromatography on Bio-Gel columns, QAE-Sephadex A-50 anion exchange columns, analytical ultracentrifugal studies, and polyacrylamide gel electrophoresis. Sedimentation velocity runs revealed a single symmetric peak with an s(sub (20,w)) value of 10.6. The molecular weight of the native enzyme, as determined by gel filtration and analytical ultracentrifugation, is 250,000 +/- 500. In polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, the molecular weight of the single polypeptide chain is 83,000 +/- 500. The purified enzyme is inhibited by palmityl-coenzyme A with a Hill interaction coefficient, n, of 2.88. These studies indicate that the ACS of aerobic Saccharomyces cerevisiae is composed of three subunits of identical or nearly identical size.