Sample records for aldehyde dehydrogenase 1a3

  1. The metabolism of ethanol-derived acetaldehyde by alcohol dehydrogenase (EC 1.1.1.1) and aldehyde dehydrogenase (EC 1.2.1.3) in Drosophila melanogaster larvae.

    PubMed Central

    Heinstra, P W; Geer, B W; Seykens, D; Langevin, M

    1989-01-01

    Both aldehyde dehydrogenase (ALDH, EC 1.2.1.3) and the aldehyde dehydrogenase activity of alcohol dehydrogenase (ADH, EC 1.1.1.1) were found to coexist in Drosophila melanogaster larvae. The enzymes, however, showed different inhibition patterns with respect to pyrazole, cyanamide and disulphiram. ALDH-1 and ALDH-2 isoenzymes were detected in larvae by electrophoretic methods. Nonetheless, in tracer studies in vivo, more than 75% of the acetaldehyde converted to acetate by the ADH ethanol-degrading pathway appeared to be also catalysed by the ADH enzyme. The larval fat body probably was the major site of this pathway. Images Fig. 1. Fig. 2. PMID:2499314

  2. Increased salivary aldehyde dehydrogenase 1 in non-reticular oral lichen planus.

    PubMed

    Mansourian, Arash; Shanbehzadeh, Najmeh; Kia, Seyed Javad; Moosavi, Mahdieh-Sadat

    2017-01-01

    Oral lichen planus is a potentially malignant disorder. One of the malignant transformation markers is cancer stem cells. One of the proposed marker for the detection of cancer stem cells's in head and neck cancer is aldehyde dehydrogenase. Recently it is shown that aldehyde dehydrogenase 1 expression in tissue samples is associated with oral lichen planus malignant transformation. This study evaluates salivary aldehyde dehydrogenase 1 in oral lichen planus. Thirty patients and 30 age and sex-matched healthy volunteers were recruited. Oral lichen planus was diagnosed based on the modified World Health Organization criteria. Subjects in the case group were divided into reticular and non-reticular forms. Unstimulated salivary samples were collected at 10-12 AM. Saliva concentrations of aldehyde dehydrogenase 1 were measured by ELISA. The differences between aldehyde dehydrogenase levels in the oral lichen planus group compared with the control group were not significant but aldehyde dehydrogenase in non-reticular oral lichen planus was significantly higher than that of the reticular form. This is a cross-sectional study, thus longitudinal studies in oral lichen planus may present similar or different results. The mechanism of malignant transformation in oral lichen planus is not defined. Previous analyses revealed that the aldehyde dehydrogenase 1 expression is significantly correlated with increased risk of transformation. This finding is consistent with our results because in the erosive and ulcerative forms of oral lichen planus, which have an increased risk of transformation, salivary aldehyde dehydrogenase 1 was overexpressed. A higher salivary aldehyde dehydrogenase level in non-reticular oral lichen planus can be a defensive mechanism against higher oxidative stress in these groups. Aldehyde dehydrogenase may be one of the malignant transformation markers in oral lichen planus. Further studies are needed for introducing aldehyde dehydrogenase as a prognostic

  3. Increased salivary aldehyde dehydrogenase 1 in non-reticular oral lichen planus*

    PubMed Central

    Mansourian, Arash; Shanbehzadeh, Najmeh; Kia, Seyed Javad; Moosavi, Mahdieh-Sadat

    2017-01-01

    Background Oral lichen planus is a potentially malignant disorder. One of the malignant transformation markers is cancer stem cells. One of the proposed marker for the detection of cancer stem cells's in head and neck cancer is aldehyde dehydrogenase. Recently it is shown that aldehyde dehydrogenase 1 expression in tissue samples is associated with oral lichen planus malignant transformation. Objective This study evaluates salivary aldehyde dehydrogenase 1 in oral lichen planus. Method Thirty patients and 30 age and sex-matched healthy volunteers were recruited. Oral lichen planus was diagnosed based on the modified World Health Organization criteria. Subjects in the case group were divided into reticular and non-reticular forms. Unstimulated salivary samples were collected at 10-12 AM. Saliva concentrations of aldehyde dehydrogenase 1 were measured by ELISA. Results The differences between aldehyde dehydrogenase levels in the oral lichen planus group compared with the control group were not significant but aldehyde dehydrogenase in non-reticular oral lichen planus was significantly higher than that of the reticular form. Limitations of the study This is a cross-sectional study, thus longitudinal studies in oral lichen planus may present similar or different results. Conclusions The mechanism of malignant transformation in oral lichen planus is not defined. Previous analyses revealed that the aldehyde dehydrogenase 1 expression is significantly correlated with increased risk of transformation. This finding is consistent with our results because in the erosive and ulcerative forms of oral lichen planus, which have an increased risk of transformation, salivary aldehyde dehydrogenase 1 was overexpressed. A higher salivary aldehyde dehydrogenase level in non-reticular oral lichen planus can be a defensive mechanism against higher oxidative stress in these groups. Aldehyde dehydrogenase may be one of the malignant transformation markers in oral lichen planus. Further

  4. Aldehyde dehydrogenase 3A1 activation prevents radiation-induced xerostomia by protecting salivary stem cells from toxic aldehydes

    PubMed Central

    Saiki, Julie P.; Cao, Hongbin; Van Wassenhove, Lauren D.; Viswanathan, Vignesh; Bloomstein, Joshua; Nambiar, Dhanya K.; Mattingly, Aaron J.; Jiang, Dadi; Chen, Che-Hong; Simmons, Amanda L.; Park, Hyun Shin; von Eyben, Rie; Kool, Eric T.; Sirjani, Davud; Knox, Sarah M.; Le, Quynh Thu; Mochly-Rosen, Daria

    2018-01-01

    Xerostomia (dry mouth) is the most common side effect of radiation therapy in patients with head and neck cancer and causes difficulty speaking and swallowing. Since aldehyde dehydrogenase 3A1 (ALDH3A1) is highly expressed in mouse salivary stem/progenitor cells (SSPCs), we sought to determine the role of ALDH3A1 in SSPCs using genetic loss-of-function and pharmacologic gain-of-function studies. Using DarkZone dye to measure intracellular aldehydes, we observed higher aldehyde accumulation in irradiated Aldh3a1−/− adult murine salisphere cells and in situ in whole murine embryonic salivary glands enriched in SSPCs compared with wild-type glands. To identify a safe ALDH3A1 activator for potential clinical testing, we screened a traditional Chinese medicine library and isolated d-limonene, commonly used as a food-flavoring agent, as a single constituent activator. ALDH3A1 activation by d-limonene significantly reduced aldehyde accumulation in SSPCs and whole embryonic glands, increased sphere-forming ability, decreased apoptosis, and improved submandibular gland structure and function in vivo after radiation. A phase 0 study in patients with salivary gland tumors showed effective delivery of d-limonene into human salivary glands following daily oral dosing. Given its safety and bioavailability, d-limonene may be a good clinical candidate for mitigating xerostomia in patients with head and neck cancer receiving radiation therapy. PMID:29794221

  5. Guinea-pig liver testosterone 17 beta-dehydrogenase (NADP+) and aldehyde reductase exhibit benzene dihydrodiol dehydrogenase activity.

    PubMed Central

    Hara, A; Hayashibara, M; Nakayama, T; Hasebe, K; Usui, S; Sawada, H

    1985-01-01

    We have kinetically and immunologically demonstrated that testosterone 17 beta-dehydrogenase (NADP+) isoenzymes (EC 1.1.1.64) and aldehyde reductase (EC 1.1.1.2) from guinea-pig liver catalyse the oxidation of benzene dihydrodiol (trans-1,2-dihydroxycyclohexa-3,5-diene) to catechol. One isoenzyme of testosterone 17 beta-dehydrogenase, which has specificity for 5 beta-androstanes, oxidized benzene dihydrodiol at a 3-fold higher rate than 5 beta-dihydrotestosterone, and showed a more than 4-fold higher affinity for benzene dihydrodiol and Vmax. value than did another isoenzyme, which exhibits specificity for 5 alpha-androstanes, and aldehyde reductase. Immunoprecipitation of guinea-pig liver cytosol with antisera against the testosterone 17 beta-dehydrogenase isoenzymes and aldehyde reductase indicated that most of the benzene dihydrodiol dehydrogenase activity in the tissue is due to testosterone 17 beta-dehydrogenase. PMID:2983661

  6. Aldehyde dehydrogenase 3A1 protects airway epithelial cells from cigarette smoke-induced DNA damage and cytotoxicity.

    PubMed

    Jang, Jun-Ho; Bruse, Shannon; Liu, Yushi; Duffy, Veronica; Zhang, Chunyu; Oyamada, Nathaniel; Randell, Scott; Matsumoto, Akiko; Thompson, David C; Lin, Yong; Vasiliou, Vasilis; Tesfaigzi, Yohannes; Nyunoya, Toru

    2014-03-01

    Aldehyde dehydrogenase 3A1 (ALDH3A1), an ALDH superfamily member, catalyzes the oxidation of reactive aldehydes, highly toxic components of cigarette smoke (CS). Even so, the role of ALDH3A1 in CS-induced cytotoxicity and DNA damage has not been examined. Among all of the ALDH superfamily members, ALDH3A1 mRNA levels showed the greatest induction in response to CS extract (CSE) exposure of primary human bronchial epithelial cells (HBECs). ALDH3A1 protein accumulation was accompanied by increased ALDH enzymatic activity in CSE-exposed immortalized HBECs. The effects of overexpression or suppression of ALDH3A1 on CSE-induced cytotoxicity and DNA damage (γH2AX) were evaluated in cultured immortalized HBECs. Enforced expression of ALDH3A1 attenuated cytotoxicity and downregulated γH2AX. SiRNA-mediated suppression of ALDH3A1 blocked ALDH enzymatic activity and augmented cytotoxicity in CSE-exposed cells. Our results suggest that the availability of ALDH3A1 is important for cell survival against CSE in HBECs. Published by Elsevier Inc.

  7. Betaine aldehyde dehydrogenase isozymes of spinach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanson, A.D.; Weretilnyk, E.A.; Weigel, P.

    1986-04-01

    Betaine is synthesized in spinach chloroplasts via the pathway Choline ..-->.. Betaine Aldehyde ..-->.. Betaine; the second step is catalyzed by betaine aldehyde dehydrogenase (BADH). The subcellular distribution of BADH was determined in leaf protoplast lysates; BADH isozymes were separated by 6-9% native PAGE. The chloroplast stromal fraction contains a single BADH isozyme (number1) that accounts for > 80% of the total protoplast activity; the extrachloroplastic fraction has a minor isozyme (number2) which migrates more slowly than number1. Both isozymes appear specific for betaine aldehyde, are more active with NAD than NADP, and show a ca. 3-fold activity increase inmore » salinized leaves. The phenotype of a natural variant of isozyme number1 suggests that the enzyme is a dimer.« less

  8. Aldehyde dehydrogenase 7A1 (ALDH7A1) is a novel enzyme involved in cellular defense against hyperosmotic stress.

    PubMed

    Brocker, Chad; Lassen, Natalie; Estey, Tia; Pappa, Aglaia; Cantore, Miriam; Orlova, Valeria V; Chavakis, Triantafyllos; Kavanagh, Kathryn L; Oppermann, Udo; Vasiliou, Vasilis

    2010-06-11

    Mammalian ALDH7A1 is homologous to plant ALDH7B1, an enzyme that protects against various forms of stress, such as salinity, dehydration, and osmotic stress. It is known that mutations in the human ALDH7A1 gene cause pyridoxine-dependent and folic acid-responsive seizures. Herein, we show for the first time that human ALDH7A1 protects against hyperosmotic stress by generating osmolytes and metabolizing toxic aldehydes. Human ALDH7A1 expression in Chinese hamster ovary cells attenuated osmotic stress-induced apoptosis caused by increased extracellular concentrations of sucrose or sodium chloride. Purified recombinant ALDH7A1 efficiently metabolized a number of aldehyde substrates, including the osmolyte precursor, betaine aldehyde, lipid peroxidation-derived aldehydes, and the intermediate lysine degradation product, alpha-aminoadipic semialdehyde. The crystal structure for ALDH7A1 supports the enzyme's substrate specificities. Tissue distribution studies in mice showed the highest expression of ALDH7A1 protein in liver, kidney, and brain, followed by pancreas and testes. ALDH7A1 protein was found in the cytosol, nucleus, and mitochondria, making it unique among the aldehyde dehydrogenase enzymes. Analysis of human and mouse cDNA sequences revealed mitochondrial and cytosolic transcripts that are differentially expressed in a tissue-specific manner in mice. In conclusion, ALDH7A1 is a novel aldehyde dehydrogenase expressed in multiple subcellular compartments that protects against hyperosmotic stress by generating osmolytes and metabolizing toxic aldehydes.

  9. Aldehyde Dehydrogenase 7A1 (ALDH7A1) Is a Novel Enzyme Involved in Cellular Defense against Hyperosmotic Stress*

    PubMed Central

    Brocker, Chad; Lassen, Natalie; Estey, Tia; Pappa, Aglaia; Cantore, Miriam; Orlova, Valeria V.; Chavakis, Triantafyllos; Kavanagh, Kathryn L.; Oppermann, Udo; Vasiliou, Vasilis

    2010-01-01

    Mammalian ALDH7A1 is homologous to plant ALDH7B1, an enzyme that protects against various forms of stress, such as salinity, dehydration, and osmotic stress. It is known that mutations in the human ALDH7A1 gene cause pyridoxine-dependent and folic acid-responsive seizures. Herein, we show for the first time that human ALDH7A1 protects against hyperosmotic stress by generating osmolytes and metabolizing toxic aldehydes. Human ALDH7A1 expression in Chinese hamster ovary cells attenuated osmotic stress-induced apoptosis caused by increased extracellular concentrations of sucrose or sodium chloride. Purified recombinant ALDH7A1 efficiently metabolized a number of aldehyde substrates, including the osmolyte precursor, betaine aldehyde, lipid peroxidation-derived aldehydes, and the intermediate lysine degradation product, α-aminoadipic semialdehyde. The crystal structure for ALDH7A1 supports the enzyme's substrate specificities. Tissue distribution studies in mice showed the highest expression of ALDH7A1 protein in liver, kidney, and brain, followed by pancreas and testes. ALDH7A1 protein was found in the cytosol, nucleus, and mitochondria, making it unique among the aldehyde dehydrogenase enzymes. Analysis of human and mouse cDNA sequences revealed mitochondrial and cytosolic transcripts that are differentially expressed in a tissue-specific manner in mice. In conclusion, ALDH7A1 is a novel aldehyde dehydrogenase expressed in multiple subcellular compartments that protects against hyperosmotic stress by generating osmolytes and metabolizing toxic aldehydes. PMID:20207735

  10. Oligo(cis-1,4-isoprene) aldehyde-oxidizing dehydrogenases of the rubber-degrading bacterium Gordonia polyisoprenivorans VH2.

    PubMed

    Vivod, Robin; Oetermann, Sylvia; Hiessl, Sebastian; Gutsche, Stefanie; Remmers, Naomi; Meinert, Christina; Voigt, Birgit; Riedel, Katharina; Steinbüchel, Alexander

    2017-11-01

    The actinomycete Gordonia polyisoprenivorans strain VH2 is well-known for its ability to efficiently degrade and catabolize natural rubber [poly(cis-1,4-isoprene)]. Recently, a pathway for the catabolism of rubber by strain VH2 was postulated based on genomic data and the analysis of mutants (Hiessl et al. in Appl Environ Microbiol 78:2874-2887, 2012). To further elucidate the degradation pathway of poly(cis-1,4-isoprene), 2-dimensional-polyacrylamide gel electrophoresis was performed. The analysis of the identified protein spots by matrix-assisted laser desorption/ionization-time of flight tandem mass spectrometry confirmed the postulated intracellular pathway suggesting a degradation of rubber via β-oxidation. In addition, other valuable information on rubber catabolism of G. polyisoprenivorans strain VH2 (e.g. oxidative stress response) was provided. Identified proteins, which were more abundant in cells grown with rubber than in cells grown with propionate, implied a putative long-chain acyl-CoA-dehydrogenase, a 3-ketoacyl-CoA-thiolase, and an aldehyde dehydrogenase. The amino acid sequence of the latter showed a high similarity towards geranial dehydrogenases. The expression of the corresponding gene was upregulated > 10-fold under poly(cis-1,4-isoprene)-degrading conditions. The putative geranial dehydrogenase and a homolog were purified and used for enzyme assays. Deletion mutants for five aldehyde dehydrogenases were generated, and growth with poly(cis-1,4-isoprene) was investigated. While none of the mutants had an altered phenotype regarding growth with poly(cis-1,4-isoprene) as sole carbon and energy source, purified aldehyde dehydrogenases were able to catalyze the oxidation of oligoisoprene aldehydes indicating an involvement in rubber degradation.

  11. Biological evaluation and 3D-QSAR studies of curcumin analogues as aldehyde dehydrogenase 1 inhibitors.

    PubMed

    Wang, Hui; Du, Zhiyun; Zhang, Changyuan; Tang, Zhikai; He, Yan; Zhang, Qiuyan; Zhao, Jun; Zheng, Xi

    2014-05-16

    Aldehyde dehydrogenase 1 (ALDH1) is reported as a biomarker for identifying some cancer stem cells, and down-regulation or inhibition of the enzyme can be effective in anti-drug resistance and a potent therapeutic for some tumours. In this paper, the inhibitory activity, mechanism mode, molecular docking and 3D-QSAR (three-dimensional quantitative structure activity relationship) of curcumin analogues (CAs) against ALDH1 were studied. Results demonstrated that curcumin and CAs possessed potent inhibitory activity against ALDH1, and the CAs compound with ortho di-hydroxyl groups showed the most potent inhibitory activity. This study indicates that CAs may represent a new class of ALDH1 inhibitor.

  12. Characterization of Two Distinct Structural Classes of Selective Aldehyde Dehydrogenase 1A1 Inhibitors

    DOE PAGES

    Morgan, Cynthia A.; Hurley, Thomas D.

    2015-01-29

    Aldehyde dehydrogenases (ALDH) catalyze the irreversible oxidation of aldehydes to their corresponding carboxylic acid. Alterations in ALDH1A1 activity are associated with such diverse diseases as cancer, Parkinson’s disease, obesity, and cataracts. Inhibitors of ALDH1A1 could aid in illuminating the role of this enzyme in disease processes. However, there are no commercially available selective inhibitors for ALDH1A1. Here we characterize two distinct chemical classes of inhibitors that are selective for human ALDH1A1 compared to eight other ALDH isoenzymes. The prototypical members of each structural class, CM026 and CM037, exhibit sub-micromolar inhibition constants, but have different mechanisms of inhibition. The crystal structuresmore » of these compounds bound to ALDH1A1 demonstrate that they bind within the aldehyde binding pocket of ALDH1A1 and exploit the presence of a unique Glycine residue to achieve their selectivity. Lastly, these two novel and selective ALDH1A1 inhibitors may serve as chemical tools to better understand the contributions of ALDH1A1 to normal biology and to disease states.« less

  13. SAXS fingerprints of aldehyde dehydrogenase oligomers.

    PubMed

    Tanner, John J

    2015-12-01

    Enzymes of the aldehyde dehydrogenase (ALDH) superfamily catalyze the nicotinamide adenine dinucleotide-dependent oxidation of aldehydes to carboxylic acids. ALDHs are important in detoxification of aldehydes, amino acid metabolism, embryogenesis and development, neurotransmission, oxidative stress, and cancer. Mutations in genes encoding ALDHs cause metabolic disorders, including alcohol flush reaction (ALDH2), Sjögren-Larsson syndrome (ALDH3A2), hyperprolinemia type II (ALDH4A1), γ-hydroxybutyric aciduria (ALDH5A1), methylmalonic aciduria (ALDH6A1), pyridoxine dependent epilepsy (ALDH7A1), and hyperammonemia (ALDH18A1). We previously reported crystal structures and small-angle X-ray scattering (SAXS) analyses of ALDHs exhibiting dimeric, tetrameric, and hexameric oligomeric states (Luo et al., Biochemistry 54 (2015) 5513-5522; Luo et al., J. Mol. Biol. 425 (2013) 3106-3120). Herein I provide the SAXS curves, radii of gyration, and distance distribution functions for the three types of ALDH oligomer. The SAXS curves and associated analysis provide diagnostic fingerprints that allow rapid identification of the type of ALDH oligomer that is present in solution. The data sets provided here serve as a benchmark for characterizing oligomerization of ALDHs.

  14. The use of tomato aminoaldehyde dehydrogenase 1 for the detection of aldehydes in fruit distillates.

    PubMed

    Frömmel, Jan; Tarkowski, Petr; Kopečný, David; Šebela, Marek

    2016-09-25

    Plant NAD(+)-dependent aminoaldehyde dehydrogenases (AMADHs, EC 1.2.1.19) belong to the family 10 of aldehyde dehydrogenases. They participate in the metabolism of polyamines or osmoprotectants. The enzymes are characterized by their broad substrate specificity covering ω-aminoaldehydes, aliphatic and aromatic aldehydes as well as nitrogen-containing heterocyclic aldehydes. The isoenzyme 1 from tomato (Solanum lycopersicum; SlAMADH1) oxidizes aliphatic aldehydes very efficiently and converts also furfural, its derivatives or benzaldehyde, which are present at low concentrations in alcoholic distillates such as fruit brandy. In this work, SlAMADH1 was examined as a bioanalytical tool for their detection. These aldehydes arise from fermentation processes or thermal degradation of sugars and their presence is related to health complications after consumption including nausea, emesis, sweating, decrease in blood pressure, hangover headache, among others. Sixteen samples of slivovitz (plum brandy) from local producers in Moravia, Czech Republic, were analyzed for their aldehyde content using a spectrophotometric activity assay with SlAMADH1. In all cases, there were oxidative responses observed when monitoring NADH production in the enzymatic reaction. Aldehydes in the distillate samples were also subjected to a standard determination using reversed-phase HPLC with spectrophotometric and tandem mass spectrometric detection after a derivatization with 2,4-dinitrophenylhydrazine. Results obtained by both methods were found to correlate well for a majority of the analyzed samples. The possible applicability of SlAMADH1 for the evaluation of aldehyde content in food and beverages has now been demonstrated. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Crystal structure of human aldehyde dehydrogenase 1A3 complexed with NAD+ and retinoic acid

    PubMed Central

    Moretti, Andrea; Li, Jianfeng; Donini, Stefano; Sobol, Robert W.; Rizzi, Menico; Garavaglia, Silvia

    2016-01-01

    The aldehyde dehydrogenase family 1 member A3 (ALDH1A3) catalyzes the oxidation of retinal to the pleiotropic factor retinoic acid using NAD+. The level of ALDHs enzymatic activity has been used as a cancer stem cell marker and seems to correlate with tumour aggressiveness. Elevated ALDH1A3 expression in mesenchymal glioma stem cells highlights the potential of this isozyme as a prognosis marker and drug target. Here we report the first crystal structure of human ALDH1A3 complexed with NAD+ and the product all-trans retinoic acid (REA). The tetrameric ALDH1A3 folds into a three domain-based architecture highly conserved along the ALDHs family. The structural analysis revealed two different and coupled conformations for NAD+ and REA that we propose to represent two snapshots along the catalytic cycle. Indeed, the isoprenic moiety of REA points either toward the active site cysteine, or moves away adopting the product release conformation. Although ALDH1A3 shares high sequence identity with other members of the ALDH1A family, our structural analysis revealed few peculiar residues in the 1A3 isozyme active site. Our data provide information into the ALDH1As catalytic process and can be used for the structure-based design of selective inhibitors of potential medical interest. PMID:27759097

  16. ALDEHYDE DEHYDROGENASES EXPRESSION DURING POSTNATAL DEVELOPMENT: LIVER VS. LUNG

    EPA Science Inventory

    Aldehydes are highly reactive molecules present in the environment, and can be produced during biotransformation of xenobiotics. Although the lung can be a major target for aldehyde toxicity, development of aldehyde dehydrogenases (ALDHs), which detoxify aldehydes, in lung has be...

  17. Fluorescence lifetime analysis and effect of magnesium ions on binding of NADH to human aldehyde dehydrogenase 1

    USDA-ARS?s Scientific Manuscript database

    Aldehyde dehydrogenase 1 (ALDH1) catalyzes oxidation of toxic aldehydes to carboxylic acids. Physiologic levels of Mg2+ ions influence ALDH1 activity in part by increasing NADH binding affinity to the enzyme thus reducing activity. By using time-resolved fluorescence spectroscopy, we have resolved t...

  18. Fatty aldehyde dehydrogenases in Acinetobacter sp. strain HO1-N: role in hexadecanol metabolism.

    PubMed Central

    Singer, M E; Finnerty, W R

    1985-01-01

    The role of fatty aldehyde dehydrogenases (FALDHs) in hexadecane and hexadecanol metabolism was studied in Acinetobacter sp. strain HO1-N. Two distinct FALDHs were demonstrated in Acinetobacter sp. strain HO1-N: a membrane-bound, NADP-dependent FALDH activity induced 5-, 15-, and 9-fold by growth on hexadecanol, dodecyl aldehyde, and hexadecane, respectively, and a constitutive, NAD-dependent, membrane-localized FALDH. The NADP-dependent FALDH exhibited apparent Km and Vmax values for decyl aldehyde of 5.0, 13.0, 18.0, and 18.3 microM and 537.0, 500.0, 25.0, and 38.0 nmol/min in hexadecane-, hexadecanol-, ethanol-, palmitate-grown cells, respectively. FALDH isozymes ald-a, ald-b, and ald-c were demonstrated by gel electrophoresis in extracts of hexadecane- and hexadecanol-grown cells. ald-a, ald-b, and ald-d were present in dodecyl aldehyde-grown cells, while palmitate-grown control cells contained ald-b and ald-d. Dodecyl aldehyde-negative mutants were isolated and grouped into two phenotypic classes based on growth: class 1 mutants were hexadecane and hexadecanol negative and class 2 mutants were hexadecane and hexadecanol positive. Specific activity of NADP-dependent FALDH in Ald21 (class 1 mutant) was 85% lower than that of wild-type FALDH, while the specific activity of Ald24 (class 2 mutant) was 55% greater than that of wild-type FALDH. Ald21R, a dodecyl aldehyde-positive revertant able to grow on hexadecane, hexadecanol, and dodecyl aldehyde, exhibited a 100% increase in the specific activity of the NADP-dependent FALDH. The oxidation of [3H]hexadecane byAld21 yielded the accumulation of 61% more fatty aldehyde than the wild type, while Ald24 accumulated 27% more fatty aldehyde, 95% more fatty alcohol, and 65% more wax ester than the wild type. This study provides genetic and physiological evidence for the role of fatty aldehyde as an essential metabolic intermediate and NADP-dependent FALDH as a key enzyme in the dissimilation of hexadecane, hexadecanol

  19. The Arabidopsis thaliana REDUCED EPIDERMAL FLUORESCENCE1 gene encodes an aldehyde dehydrogenase involved in ferulic acid and sinapic acid biosynthesis.

    PubMed

    Nair, Ramesh B; Bastress, Kristen L; Ruegger, Max O; Denault, Jeff W; Chapple, Clint

    2004-02-01

    Recent research has significantly advanced our understanding of the phenylpropanoid pathway but has left in doubt the pathway by which sinapic acid is synthesized in plants. The reduced epidermal fluorescence1 (ref1) mutant of Arabidopsis thaliana accumulates only 10 to 30% of the sinapate esters found in wild-type plants. Positional cloning of the REF1 gene revealed that it encodes an aldehyde dehydrogenase, a member of a large class of NADP(+)-dependent enzymes that catalyze the oxidation of aldehydes to their corresponding carboxylic acids. Consistent with this finding, extracts of ref1 leaves exhibit low sinapaldehyde dehydrogenase activity. These data indicate that REF1 encodes a sinapaldehyde dehydrogenase required for sinapic acid and sinapate ester biosynthesis. When expressed in Escherichia coli, REF1 was found to exhibit both sinapaldehyde and coniferaldehyde dehydrogenase activity, and further phenotypic analysis of ref1 mutant plants showed that they contain less cell wall-esterified ferulic acid. These findings suggest that both ferulic acid and sinapic acid are derived, at least in part, through oxidation of coniferaldehyde and sinapaldehyde. This route is directly opposite to the traditional representation of phenylpropanoid metabolism in which hydroxycinnamic acids are instead precursors of their corresponding aldehydes.

  20. The Arabidopsis thaliana REDUCED EPIDERMAL FLUORESCENCE1 Gene Encodes an Aldehyde Dehydrogenase Involved in Ferulic Acid and Sinapic Acid Biosynthesis

    PubMed Central

    Nair, Ramesh B.; Bastress, Kristen L.; Ruegger, Max O.; Denault, Jeff W.; Chapple, Clint

    2004-01-01

    Recent research has significantly advanced our understanding of the phenylpropanoid pathway but has left in doubt the pathway by which sinapic acid is synthesized in plants. The reduced epidermal fluorescence1 (ref1) mutant of Arabidopsis thaliana accumulates only 10 to 30% of the sinapate esters found in wild-type plants. Positional cloning of the REF1 gene revealed that it encodes an aldehyde dehydrogenase, a member of a large class of NADP+-dependent enzymes that catalyze the oxidation of aldehydes to their corresponding carboxylic acids. Consistent with this finding, extracts of ref1 leaves exhibit low sinapaldehyde dehydrogenase activity. These data indicate that REF1 encodes a sinapaldehyde dehydrogenase required for sinapic acid and sinapate ester biosynthesis. When expressed in Escherichia coli, REF1 was found to exhibit both sinapaldehyde and coniferaldehyde dehydrogenase activity, and further phenotypic analysis of ref1 mutant plants showed that they contain less cell wall–esterified ferulic acid. These findings suggest that both ferulic acid and sinapic acid are derived, at least in part, through oxidation of coniferaldehyde and sinapaldehyde. This route is directly opposite to the traditional representation of phenylpropanoid metabolism in which hydroxycinnamic acids are instead precursors of their corresponding aldehydes. PMID:14729911

  1. DEVELOPMENTAL EXPRESSION OF ALDEHYDE DEHYDROGENASE IN RAT: A COMPARISON OF LIVER AND LUNG DEVELOPMENT

    EPA Science Inventory

    Metabolism is one of the major determinants for age-related susceptibility changes to chemicals. Aldehydes are highly reactive molecules present in the environment and can be produced during biotransformation of xenobiotics. Aldehyde dehydrogenases (ALDH) are important in aldehyd...

  2. Aldehyde dehydrogenase 1a1 mediates a GABA synthesis pathway in midbrain dopaminergic neurons.

    PubMed

    Kim, Jae-Ick; Ganesan, Subhashree; Luo, Sarah X; Wu, Yu-Wei; Park, Esther; Huang, Eric J; Chen, Lu; Ding, Jun B

    2015-10-02

    Midbrain dopamine neurons are an essential component of the basal ganglia circuitry, playing key roles in the control of fine movement and reward. Recently, it has been demonstrated that γ-aminobutyric acid (GABA), the chief inhibitory neurotransmitter, is co-released by dopamine neurons. Here, we show that GABA co-release in dopamine neurons does not use the conventional GABA-synthesizing enzymes, glutamate decarboxylases GAD65 and GAD67. Our experiments reveal an evolutionarily conserved GABA synthesis pathway mediated by aldehyde dehydrogenase 1a1 (ALDH1a1). Moreover, GABA co-release is modulated by ethanol (EtOH) at concentrations seen in blood alcohol after binge drinking, and diminished ALDH1a1 leads to enhanced alcohol consumption and preference. These findings provide insights into the functional role of GABA co-release in midbrain dopamine neurons, which may be essential for reward-based behavior and addiction. Copyright © 2015, American Association for the Advancement of Science.

  3. Structural and functional analysis of betaine aldehyde dehydrogenase from Staphylococcus aureus.

    PubMed

    Halavaty, Andrei S; Rich, Rebecca L; Chen, Chao; Joo, Jeong Chan; Minasov, George; Dubrovska, Ievgeniia; Winsor, James R; Myszka, David G; Duban, Mark; Shuvalova, Ludmilla; Yakunin, Alexander F; Anderson, Wayne F

    2015-05-01

    When exposed to high osmolarity, methicillin-resistant Staphylococcus aureus (MRSA) restores its growth and establishes a new steady state by accumulating the osmoprotectant metabolite betaine. Effective osmoregulation has also been implicated in the acquirement of a profound antibiotic resistance by MRSA. Betaine can be obtained from the bacterial habitat or produced intracellularly from choline via the toxic betaine aldehyde (BA) employing the choline dehydrogenase and betaine aldehyde dehydrogenase (BADH) enzymes. Here, it is shown that the putative betaine aldehyde dehydrogenase SACOL2628 from the early MRSA isolate COL (SaBADH) utilizes betaine aldehyde as the primary substrate and nicotinamide adenine dinucleotide (NAD(+)) as the cofactor. Surface plasmon resonance experiments revealed that the affinity of NAD(+), NADH and BA for SaBADH is affected by temperature, pH and buffer composition. Five crystal structures of the wild type and three structures of the Gly234Ser mutant of SaBADH in the apo and holo forms provide details of the molecular mechanisms of activity and substrate specificity/inhibition of this enzyme.

  4. Structural and functional analysis of betaine aldehyde dehydrogenase from Staphylococcus aureus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Halavaty, Andrei S.; Rich, Rebecca L.; Chen, Chao

    When exposed to high osmolarity, methicillin-resistant Staphylococcus aureus (MRSA) restores its growth and establishes a new steady state by accumulating the osmoprotectant metabolite betaine. Effective osmoregulation has also been implicated in the acquirement of a profound antibiotic resistance by MRSA. Betaine can be obtained from the bacterial habitat or produced intracellularly from choline via the toxic betaine aldehyde (BA) employing the choline dehydrogenase and betaine aldehyde dehydrogenase (BADH) enzymes. Here, it is shown that the putative betaine aldehyde dehydrogenase SACOL2628 from the early MRSA isolate COL ( SaBADH) utilizes betaine aldehyde as the primary substrate and nicotinamide adenine dinucleotide (NADmore » +) as the cofactor. Surface plasmon resonance experiments revealed that the affinity of NAD +, NADH and BA for SaBADH is affected by temperature, pH and buffer composition. Finally, five crystal structures of the wild type and three structures of the Gly234Ser mutant of SaBADH in the apo and holo forms provide details of the molecular mechanisms of activity and substrate specificity/inhibition of this enzyme.« less

  5. Structural and functional analysis of betaine aldehyde dehydrogenase from Staphylococcus aureus

    DOE PAGES

    Halavaty, Andrei S.; Rich, Rebecca L.; Chen, Chao; ...

    2015-04-25

    When exposed to high osmolarity, methicillin-resistant Staphylococcus aureus (MRSA) restores its growth and establishes a new steady state by accumulating the osmoprotectant metabolite betaine. Effective osmoregulation has also been implicated in the acquirement of a profound antibiotic resistance by MRSA. Betaine can be obtained from the bacterial habitat or produced intracellularly from choline via the toxic betaine aldehyde (BA) employing the choline dehydrogenase and betaine aldehyde dehydrogenase (BADH) enzymes. Here, it is shown that the putative betaine aldehyde dehydrogenase SACOL2628 from the early MRSA isolate COL ( SaBADH) utilizes betaine aldehyde as the primary substrate and nicotinamide adenine dinucleotide (NADmore » +) as the cofactor. Surface plasmon resonance experiments revealed that the affinity of NAD +, NADH and BA for SaBADH is affected by temperature, pH and buffer composition. Finally, five crystal structures of the wild type and three structures of the Gly234Ser mutant of SaBADH in the apo and holo forms provide details of the molecular mechanisms of activity and substrate specificity/inhibition of this enzyme.« less

  6. Structural and Kinetic Properties of the Aldehyde Dehydrogenase NahF, a Broad Substrate Specificity Enzyme for Aldehyde Oxidation.

    PubMed

    Coitinho, Juliana B; Pereira, Mozart S; Costa, Débora M A; Guimarães, Samuel L; Araújo, Simara S; Hengge, Alvan C; Brandão, Tiago A S; Nagem, Ronaldo A P

    2016-09-27

    The salicylaldehyde dehydrogenase (NahF) catalyzes the oxidation of salicylaldehyde to salicylate using NAD(+) as a cofactor, the last reaction of the upper degradation pathway of naphthalene in Pseudomonas putida G7. The naphthalene is an abundant and toxic compound in oil and has been used as a model for bioremediation studies. The steady-state kinetic parameters for oxidation of aliphatic or aromatic aldehydes catalyzed by 6xHis-NahF are presented. The 6xHis-NahF catalyzes the oxidation of aromatic aldehydes with large kcat/Km values close to 10(6) M(-1) s(-1). The active site of NahF is highly hydrophobic, and the enzyme shows higher specificity for less polar substrates than for polar substrates, e.g., acetaldehyde. The enzyme shows α/β folding with three well-defined domains: the oligomerization domain, which is responsible for the interlacement between the two monomers; the Rossmann-like fold domain, essential for nucleotide binding; and the catalytic domain. A salicylaldehyde molecule was observed in a deep pocket in the crystal structure of NahF where the catalytic C284 and E250 are present. Moreover, the residues G150, R157, W96, F99, F274, F279, and Y446 were thought to be important for catalysis and specificity for aromatic aldehydes. Understanding the molecular features responsible for NahF activity allows for comparisons with other aldehyde dehydrogenases and, together with structural information, provides the information needed for future mutational studies aimed to enhance its stability and specificity and further its use in biotechnological processes.

  7. Targeting Aldehyde Dehydrogenase: a Potential Approach for Cell labeling

    PubMed Central

    Vaidyanathan, Ganesan; Song, Haijing; Affleck, Donna; McDougald, Darryl L.; Storms, Robert W.; Zalutksy, Michael R.; Chin, Bennett B.

    2009-01-01

    Introduction To advance the science and clinical application of stem cell therapy, the availability of a highly sensitive, quantitative, and translational method for tracking stem cells would be invaluable. Because hematopoetic stem cells express high levels of the cytosolic enzyme aldehyde dehydrogenase-1A1 (ALDH1), we sought to develop an agent that is specific to ALDH1 and thus to cells expressing the enzyme. Such an agent might be also helpful in identifying tumors that are resistant to cyclophosphomide chemotherapy because ALDH1 is known to be responsible for this resistance. Methods We developed schemes for the synthesis of two 3radioiodinated aldehdyes—N-formylmethyl-5-[*I]iodopyridine-3-carboxamide ([*I]FMIC) and 4-diethylamino-3-[*I]iodobenzaldehyde ([*I]DEIBA)—at no-carrier-added levels from their respective tin precursors. These agents were evaluated using pure ALDH1 and tumor cells that expressed the enzyme. Results The average radiochemical yields for the synthesis [125I]FMIC and [125I]DEIBA were 70 ± 5% and 47 ± 14%, respectively. ALDH1 converted both compounds to respective acids suggesting their suitability as ALDH1 imaging agents. Although ability of ALDH1 within the cells to oxidize one of these substrates was shown, specific uptake in ALDH-expressing tumor cells could not be demonstrated. Conclusion To pursue this approach for ALDH1 imaging, radiolabeled aldehydes need to be designed such that, in addition to being good substrates for ALDH1, the cognate products should be sufficiently polar so as to be retained within the cells. PMID:19875048

  8. Inhibition of Wnt/beta-catenin signaling downregulates expression of aldehyde dehydrogenase isoform 3A1 (ALDH3A1) to reduce resistance against temozolomide in glioblastoma in vitro.

    PubMed

    Suwala, Abigail Kora; Koch, Katharina; Rios, Dayana Herrera; Aretz, Philippe; Uhlmann, Constanze; Ogorek, Isabella; Felsberg, Jörg; Reifenberger, Guido; Köhrer, Karl; Deenen, René; Steiger, Hans-Jakob; Kahlert, Ulf D; Maciaczyk, Jaroslaw

    2018-04-27

    Glioblastoma is the most aggressive type of glioma. The Wingless (Wnt) signaling pathway has been shown to promote stem cell properties and resistance to radio- and chemotherapy in glioblastoma. Here, we demonstrate that pharmacological Wnt pathway inhibition using the porcupine inhibitor LGK974 acts synergistically with temozolomide (TMZ), the chemotherapeutic drug currently used as standard treatment for glioblastoma, to suppress in vitro growth of glioma cells. Synergistic growth inhibition was independent of the O 6 -alkylguanine DNA alkyltransferase ( MGMT ) promoter methylation status. Transcriptomic analysis revealed that expression of aldehyde dehydrogenase 3A1 ( ALDH3A1 ) was significantly down-regulated when cells were treated with LGK974 and TMZ. Suppressing ALDH3A1 expression increased the efficacy of TMZ and reduced clonogenic potential accompanied by decreased expression of stem cell markers CD133, Nestin and Sox2. Taken together, our study suggests that previous observations concerning Wnt signaling blockade to reduce chemoresistance in glioblastoma is at least in part mediated by inhibition of ALDH3A1.

  9. Inhibition effects of furfural on alcohol dehydrogenase, aldehyde dehydrogenase and pyruvate dehydrogenase.

    PubMed Central

    Modig, Tobias; Lidén, Gunnar; Taherzadeh, Mohammad J

    2002-01-01

    The kinetics of furfural inhibition of the enzymes alcohol dehydrogenase (ADH; EC 1.1.1.1), aldehyde dehydrogenase (AlDH; EC 1.2.1.5) and the pyruvate dehydrogenase (PDH) complex were studied in vitro. At a concentration of less than 2 mM furfural was found to decrease the activity of both PDH and AlDH by more than 90%, whereas the ADH activity decreased by less than 20% at the same concentration. Furfural inhibition of ADH and AlDH activities could be described well by a competitive inhibition model, whereas the inhibition of PDH was best described as non-competitive. The estimated K(m) value of AlDH for furfural was found to be about 5 microM, which was lower than that for acetaldehyde (10 microM). For ADH, however, the estimated K(m) value for furfural (1.2 mM) was higher than that for acetaldehyde (0.4 mM). The inhibition of the three enzymes by 5-hydroxymethylfurfural (HMF) was also measured. The inhibition caused by HMF of ADH was very similar to that caused by furfural. However, HMF did not inhibit either AlDH or PDH as severely as furfural. The inhibition effects on the three enzymes could well explain previously reported in vivo effects caused by furfural and HMF on the overall metabolism of Saccharomyces cerevisiae, suggesting a critical role of these enzymes in the observed inhibition. PMID:11964178

  10. Evaluation of alcohol dehydrogenase and aldehyde dehydrogenase enzymes as bi-enzymatic anodes in a membraneless ethanol microfluidic fuel cell

    NASA Astrophysics Data System (ADS)

    Galindo-de-la-Rosa, J.; Arjona, N.; Arriaga, L. G.; Ledesma-García, J.; Guerra-Balcázar, M.

    2015-12-01

    Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (AldH) enzymes were immobilized by covalent binding and used as the anode in a bi-enzymatic membraneless ethanol hybrid microfluidic fuel cell. The purpose of using both enzymes was to optimize the ethanol electro-oxidation reaction (EOR) by using ADH toward its direct oxidation and AldH for the oxidation of aldehydes as by-products of the EOR. For this reason, three enzymatic bioanode configurations were evaluated according with the location of enzymes: combined, vertical and horizontally separated. In the combined configuration, a current density of 16.3 mA cm-2, a voltage of 1.14 V and a power density of 7.02 mW cm-2 were obtained. When enzymes were separately placed in a horizontal and vertical position the ocp drops to 0.94 V and to 0.68 V, respectively. The current density also falls to values of 13.63 and 5.05 mA cm-2. The decrease of cell performance of bioanodes with separated enzymes compared with the combined bioanode was of 31.7% and 86.87% for the horizontal and the vertical array.

  11. Aldehydic load and aldehyde dehydrogenase 2 profile during the progression of post-myocardial infarction cardiomyopathy: benefits of Alda-1

    PubMed Central

    Gomes, Katia M.S.; Bechara, Luiz R.G.; Lima, Vanessa M.; Ribeiro, Márcio A.C.; Campos, Juliane C.; Dourado, Paulo M.; Kowaltowski, Alicia J.; Mochly-Rosen, Daria; Ferreira, Julio C.B.

    2015-01-01

    Background/Objectives We previously demonstrated that reducing cardiac aldehydic load by aldehyde dehydrogenase 2 (ALDH2), a mitochondrial enzyme responsible for metabolizing the major lipid peroxidation product, protects against acute ischemia/reperfusion injury and chronic heart failure. However, time-dependent changes in ALDH2 profile, aldehydic load and mitochondrial bioenergetics during progression of post-myocardial infarction (post-MI) cardiomyopathy is unknown and should be established to determine the optimal time window for drug treatment. Methods Here we characterized cardiac ALDH2 activity and expression, lipid peroxidation, 4-hydroxy-2-nonenal (4-HNE) adduct formation, glutathione pool and mitochondrial energy metabolism and H2O2 release during the 4 weeks after permanent left anterior descending (LAD) coronary artery occlusion in rats. Results We observed a sustained disruption of cardiac mitochondrial function during the progression of post-MI cardiomyopathy, characterized by >50% reduced mitochondrial respiratory control ratios and up to 2 fold increase in H2O2 release. Mitochondrial dysfunction was accompanied by accumulation of cardiac and circulating lipid peroxides and 4-HNE protein adducts and down-regulation of electron transport chain complexes I and V. Moreover, increased aldehydic load was associated with a 90% reduction in cardiac ALDH2 activity and increased glutathione pool. Further supporting an ALDH2 mechanism, sustained Alda-1 treatment (starting 24hrs after permanent LAD occlusion surgery) prevented aldehydic overload, mitochondrial dysfunction and improved ventricular function in post-MI cardiomyopathy rats. Conclusion Taken together, our findings demonstrate a disrupted mitochondrial metabolism along with an insufficient cardiac ALDH2-mediated aldehyde clearance during the progression of ventricular dysfunction, suggesting a potential therapeutic value of ALDH2 activators during the progression of post-myocardial infarction

  12. Aldehyde Dehydrogenases in Arabidopsis thaliana: Biochemical Requirements, Metabolic Pathways, and Functional Analysis.

    PubMed

    Stiti, Naim; Missihoun, Tagnon D; Kotchoni, Simeon O; Kirch, Hans-Hubert; Bartels, Dorothea

    2011-01-01

    Aldehyde dehydrogenases (ALDHs) are a family of enzymes which catalyze the oxidation of reactive aldehydes to their corresponding carboxylic acids. Here we summarize molecular genetic and biochemical analyses of selected ArabidopsisALDH genes. Aldehyde molecules are very reactive and are involved in many metabolic processes but when they accumulate in excess they become toxic. Thus activity of aldehyde dehydrogenases is important in regulating the homeostasis of aldehydes. Overexpression of some ALDH genes demonstrated an improved abiotic stress tolerance. Despite the fact that several reports are available describing a role for specific ALDHs, their precise physiological roles are often still unclear. Therefore a number of genetic and biochemical tools have been generated to address the function with an emphasis on stress-related ALDHs. ALDHs exert their functions in different cellular compartments and often in a developmental and tissue specific manner. To investigate substrate specificity, catalytic efficiencies have been determined using a range of substrates varying in carbon chain length and degree of carbon oxidation. Mutational approaches identified amino acid residues critical for coenzyme usage and enzyme activities.

  13. Aldehyde Dehydrogenases in Arabidopsis thaliana: Biochemical Requirements, Metabolic Pathways, and Functional Analysis

    PubMed Central

    Stiti, Naim; Missihoun, Tagnon D.; Kotchoni, Simeon O.; Kirch, Hans-Hubert; Bartels, Dorothea

    2011-01-01

    Aldehyde dehydrogenases (ALDHs) are a family of enzymes which catalyze the oxidation of reactive aldehydes to their corresponding carboxylic acids. Here we summarize molecular genetic and biochemical analyses of selected Arabidopsis ALDH genes. Aldehyde molecules are very reactive and are involved in many metabolic processes but when they accumulate in excess they become toxic. Thus activity of aldehyde dehydrogenases is important in regulating the homeostasis of aldehydes. Overexpression of some ALDH genes demonstrated an improved abiotic stress tolerance. Despite the fact that several reports are available describing a role for specific ALDHs, their precise physiological roles are often still unclear. Therefore a number of genetic and biochemical tools have been generated to address the function with an emphasis on stress-related ALDHs. ALDHs exert their functions in different cellular compartments and often in a developmental and tissue specific manner. To investigate substrate specificity, catalytic efficiencies have been determined using a range of substrates varying in carbon chain length and degree of carbon oxidation. Mutational approaches identified amino acid residues critical for coenzyme usage and enzyme activities. PMID:22639603

  14. The prognostic impact of cancer stem-like cell biomarker aldehyde dehydrogenase-1 (ALDH1) in ovarian cancer: A meta-analysis.

    PubMed

    Ruscito, Ilary; Darb-Esfahani, Silvia; Kulbe, Hagen; Bellati, Filippo; Zizzari, Ilaria Grazia; Rahimi Koshkaki, Hassan; Napoletano, Chiara; Caserta, Donatella; Rughetti, Aurelia; Kessler, Mirjana; Sehouli, Jalid; Nuti, Marianna; Braicu, Elena Ioana

    2018-05-10

    To investigate the association of cancer stem cell biomarker aldehyde dehydrogenase-1 (ALDH1) with ovarian cancer patients' prognosis and clinico-pathological characteristics. The electronic searches were performed in January 2018 through the databases PubMed, MEDLINE and Scopus by searching the terms: "ovarian cancer" AND "immunohistochemistry" AND ["aldehyde dehydrogenase-1" OR "ALDH1" OR "cancer stem cell"]. Studies evaluating the impact of ALDH1 expression on ovarian cancer survival and clinico-pathological variables were selected. 233 studies were retrieved. Thirteen studies including 1885 patients met all selection criteria. ALDH1-high expression was found to be significantly associated with poor 5-year OS (OR = 3.46; 95% CI: 1.61-7.42; P = 0.001, random effects model) and 5-year PFS (OR = 2.14; 95% CI: 1.11-4.13; P = 0.02, random effects model) in ovarian cancer patients. No correlation between ALDH1 expression and tumor histology (OR = 0.60; 95% CI: 0.36-1.02; P = 0.06, random effects model), FIGO Stage (OR = 0.65; 95% CI: 0.33-1.30; P = 0.22, random effects model), tumor grading (OR = 0.76; 95% CI: 0.40-1.45; P = 0.41, random effects model) lymph nodal status (OR = 2.05; 95% CI: 0.81-5.18; P = 0.13, random effects model) or patients' age at diagnosis (OR = 0.83; 95% CI: 0.54-1.29; P = 0.41, fixed effects model) was identified. Basing on the available evidence, this meta-analysis showed that high levels of ALDH1 expression correlate with worse OS and PFS in ovarian cancer patients. Copyright © 2018. Published by Elsevier Inc.

  15. Different specificities of two aldehyde dehydrogenases from Saccharomyces cerevisiae var. boulardii.

    PubMed

    Datta, Suprama; Annapure, Uday S; Timson, David J

    2017-04-30

    Aldehyde dehydrogenases play crucial roles in the detoxification of exogenous and endogenous aldehydes by catalysing their oxidation to carboxylic acid counterparts. The present study reports characterization of two such isoenzymes from the yeast Saccharomyces cerevisiae var. boulardii (NCYC 3264), one mitochondrial (Ald4p) and one cytosolic (Ald6p). Both Ald4p and Ald6p were oligomeric in solution and demonstrated positive kinetic cooperativity towards aldehyde substrates. Wild-type Ald6p showed activity only with aliphatic aldehydes. Ald4p, on the contrary, showed activity with benzaldehyde along with a limited range of aliphatic aldehydes. Inspection of modelled structure of Ald6p revealed that a bulky amino acid residue (Met 177 , compared with the equivalent residue Leu 196 in Ald4p) might cause steric hindrance of cyclic substrates. Therefore, we hypothesized that specificities of the two isoenzymes towards aldehyde substrates were partly driven by steric hindrance in the active site. A variant of wild-type Ald6p with the Met 177 residue replaced by a valine was also characterized to address to the hypothesis. It showed an increased specificity range and a gain of activity towards cyclohexanecarboxaldehyde. It also demonstrated an increased thermal stability when compared with both the wild-types. These data suggest that steric bulk in the active site of yeast aldehyde dehydrogenases is partially responsible for controlling specificity. © 2017 The Author(s).

  16. Insight into Coenzyme A cofactor binding and the mechanism of acyl-transfer in an acylating aldehyde dehydrogenase from Clostridium phytofermentans

    PubMed Central

    Tuck, Laura R.; Altenbach, Kirsten; Ang, Thiau Fu; Crawshaw, Adam D.; Campopiano, Dominic J.; Clarke, David J.; Marles-Wright, Jon

    2016-01-01

    The breakdown of fucose and rhamnose released from plant cell walls by the cellulolytic soil bacterium Clostridium phytofermentans produces toxic aldehyde intermediates. To enable growth on these carbon sources, the pathway for the breakdown of fucose and rhamnose is encapsulated within a bacterial microcompartment (BMC). These proteinaceous organelles sequester the toxic aldehyde intermediates and allow the efficient action of acylating aldehyde dehydrogenase enzymes to produce an acyl-CoA that is ultimately used in substrate-level phosphorylation to produce ATP. Here we analyse the kinetics of the aldehyde dehydrogenase enzyme from the fucose/rhamnose utilisation BMC with different short-chain fatty aldehydes and show that it has activity against substrates with up to six carbon atoms, with optimal activity against propionaldehyde. We have also determined the X-ray crystal structure of this enzyme in complex with CoA and show that the adenine nucleotide of this cofactor is bound in a distinct pocket to the same group in NAD+. This work is the first report of the structure of CoA bound to an aldehyde dehydrogenase enzyme and our crystallographic model provides important insight into the differences within the active site that distinguish the acylating from non-acylating aldehyde dehydrogenase enzymes. PMID:26899032

  17. Insight into Coenzyme A cofactor binding and the mechanism of acyl-transfer in an acylating aldehyde dehydrogenase from Clostridium phytofermentans.

    PubMed

    Tuck, Laura R; Altenbach, Kirsten; Ang, Thiau Fu; Crawshaw, Adam D; Campopiano, Dominic J; Clarke, David J; Marles-Wright, Jon

    2016-02-22

    The breakdown of fucose and rhamnose released from plant cell walls by the cellulolytic soil bacterium Clostridium phytofermentans produces toxic aldehyde intermediates. To enable growth on these carbon sources, the pathway for the breakdown of fucose and rhamnose is encapsulated within a bacterial microcompartment (BMC). These proteinaceous organelles sequester the toxic aldehyde intermediates and allow the efficient action of acylating aldehyde dehydrogenase enzymes to produce an acyl-CoA that is ultimately used in substrate-level phosphorylation to produce ATP. Here we analyse the kinetics of the aldehyde dehydrogenase enzyme from the fucose/rhamnose utilisation BMC with different short-chain fatty aldehydes and show that it has activity against substrates with up to six carbon atoms, with optimal activity against propionaldehyde. We have also determined the X-ray crystal structure of this enzyme in complex with CoA and show that the adenine nucleotide of this cofactor is bound in a distinct pocket to the same group in NAD(+). This work is the first report of the structure of CoA bound to an aldehyde dehydrogenase enzyme and our crystallographic model provides important insight into the differences within the active site that distinguish the acylating from non-acylating aldehyde dehydrogenase enzymes.

  18. In vivo antitumor activity of 4-amino 4-methyl 2-pentyne 1-al, an inhibitor of aldehyde dehydrogenase.

    PubMed

    Quemener, V; Quash, G; Moulinoux, J P; Penlap, V; Ripoll, H; Havouis, R; Doutheau, A; Goré, J

    1989-01-01

    4-amino-4-methyl-2-pentyne-1-al (AMPAL), a new irreversible inhibitor of aldehyde dehydrogenase (ALDH) has been assayed for its in vitro and in vivo antitumor activity. In vitro, AMPAL inhibits the proliferation and the ALDH activity of L1210 and RBL5 cell lines. In vivo, AMPAL significantly increases the mean survival time of mice i.p. grafted with leukemia (L1210, P815, MBL2, EL4, RBL5 cell lines) or carcinoma cells (Krebs cell line), without haematopoetic toxicity. No carcinostatic effect was observed against the P388 leukemia and the 3LL Lewis lung carcinoma. A possible relationship between the ALDH isoenzyme activity of the tumor and its sensitivity to AMPAL is discussed in the light of previous reports concerning the role of aldehydes in cell growth control.

  19. Murine hepatic aldehyde dehydrogenase 1a1 is a major contributor to oxidation of aldehydes formed by lipid peroxidation

    PubMed Central

    Makia, Ngome L.; Bojang, Pasano; Falkner, K. Cameron; Conklin, Daniel J.; Prough, Russell A.

    2015-01-01

    Reactive lipid aldehydes are implicated in the pathogenesis of various oxidative stress-mediated diseases, including non-alcoholic steatohepatitis, atherosclerosis, Alzheimer’s and cataract. In the present study, we sought to define which hepatic Aldh isoform plays a major role in detoxification of lipid-derived aldehydes, such as acrolein and HNE by enzyme kinetic and gene expression studies. The catalytic efficiencies for metabolism of acrolein by Aldh1a1 was comparable to that of Aldh3a1 (Vmax/Km = 23). However, Aldh1a1 exhibits far higher affinity for acrolein (Km = 23.2 μM) compared to Aldh3a1 (Km = 464 μM). Aldh1a1 displays a 3-fold higher catalytic efficiency for HNE than Aldh3a1 (218 vs 69 ml/min/mg). The endogenous Aldh1a1 gene was highly expressed in mouse liver and a liver-derived cell line (Hepa-1c1c7) compared to Aldh2, Aldh1b1 and Aldh3a1. Aldh1a1 mRNA levels was 34-fold and 73-fold higher than Aldh2 in mouse liver and Hepa-1c1c7 cells respectively. Aldh3a1 gene was absent in mouse liver, but moderately expressed in Hepa-1c1c7 cells compared to Aldh1a1. We demonstrated that knockdown of Aldh1a1 expression by siRNA caused Hepa-1c1c7 cells to be more sensitive to acrolein-induced cell death and resulted in increased accumulation of acrolein-protein adducts and caspase 3 activation. These results indicate that Aldh1a1 plays a major role in cellular defense against oxidative damage induced by reactive lipid aldehydes in mouse liver. We also noted that hepatic Aldh1a1 mRNA levels were significantly increased (≈ 3 fold) in acrolein-fed mice compared to control. In addition, hepatic cytosolic ALDH activity was induced by acrolein when 1 mM NAD+ was used as cofactor, suggesting an Aldh1a1-protective mechanism against acrolein toxicity in mice liver. Thus, mechanisms to induce Aldh1a1 gene expression may provide a useful rationale for therapeutic protection against oxidative stress-induced pathologies. PMID:21256123

  20. A specific affinity reagent to distinguish aldehyde dehydrogenases and oxidases. Enzymes catalyzing aldehyde oxidation in an adult moth

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tasayco, M.L.; Prestwich, G.D.

    1990-02-25

    Aldehyde dehydrogenase (ALDH) and oxidase (AO) enzymes from the tissue extracts of male and female tobacco budworm moth (Heliothis virescens) were identified after electrophoretic protein separation. AO activity was visualized using formazan- or horseradish peroxidase-mediated staining coupled to the AO-catalyzed oxidation of benzaldehyde. A set of six soluble AO enzymes with isoelectric points from pI 4.6 to 5.3 were detected primarily in the antennal extracts. Partially purified antennal AO enzymes also oxidized both (Z)-9-tetradecenal and (Z)-11-hexadecenal, the two major pheromone components of this moth. ALDH activity was detected using a tritium-labeled affinity reagent based on a known irreversible inhibitor ofmore » this enzyme. This labeled vinyl ketone, (3H)(Z)-1,11-hexadecadien-3-one, was synthesized and used to covalently modify the soluble ALDH enzymes from tissue extracts. Molecular subunits of potential ALDH enzymes were visualized in the fluorescence autoradiograms of sodium dodecyl sulfate-polyacrylamide gel electrophoresis-separated proteins of the antenna, head, and leg tissues. Covalent modification of these protein subunits decreased specifically in the presence of excess pheromone aldehyde or benzaldehyde. Labeled vinyl ketones are thus novel tools for the identification of molecular subunits of ALDH enzymes.« less

  1. [Distribution of genotypes of alcohol dehydrogenase 2 and aldehyde dehydrogenase 2 in Japanese twin children].

    PubMed

    Qu, W; Yamagata, Z; Wu, D; Zhang, B; Zhang, Y

    1999-03-01

    In order to prevent alcohol related deseases, this study investigated the distribution of the genes controlling alcohol metabolism in Japan's twin. Restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) technique was used to measure the control gene of alcohol metabolized enzymes and the genotypes of alcohol dehydrogenase 2 (ADH2) and aldehyde dehydrogenase 2 (ALDH2), which were distributed in Japan's twins. At the same time, according to the difference in genotypes, the sensitive individuals were screened from the study subjects. The distribution of ADH2 and ALDH2 genes were consistent with the Hardy-weinberg equation. The three genotypes of ADH2 gene were ADH2(1)/ADH2(1) (1.1%), ADH2(1)/ADH2(2) (44.6%) and ADH2(2)/ADH2(2) (54.3%). And those of ALDH2 gene were ALDH2(1)/ALDH2(1) (41.3%), ALDH2(1)/ALDH2(2) (39.1%) and ALDH2(2)/ALDH2(2) (19.6%). The frequency of ADH2 and ALDH2 genes was 0.255, 0.745 and 0.609, 0.391 respectively. Not only the distribution of genotypes of ADH2 and ALDH2 is known, but also the sensitive individuals are found, which can help prevent alcohol related disease.

  2. Heat-stable, FE-dependent alcohol dehydrogenase for aldehyde detoxification

    DOEpatents

    Elkins, James G.; Clarkson, Sonya

    2018-04-24

    The present invention relates to microorganisms and polypeptides for detoxifying aldehydes associated with industrial fermentations. In particular, a heat-stable, NADPH- and iron-dependent alcohol dehydrogenase was cloned from Thermoanaerobacter pseudethanolicus 39E and displayed activity against a number of aldehydes including inhibitory compounds that are produced during the dilute-acid pretreatment process of lignocellulosic biomass before fermentation to biofuels. Methods to use the microorganisms and polypeptides of the invention for improved conversion of bio mass to biofuel are provided as well as use of the enzyme in metabolic engineering strategies for producing longer-chain alcohols from sugars using thermophilic, fermentative microorganisms.

  3. Cloning and heterologous expression of two aryl-aldehyde dehydrogenases from the white-rot basidiomycete Phanerochaete chrysosporium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nakamura, Tomofumi; Fukuoka Institute of Health and Environmental Sciences, 39 Mukaizano, Dazaifu-shi, Fukuoka 818-0135; Ichinose, Hirofumi

    2010-04-09

    We identified two aryl-aldehyde dehydrogenase proteins (PcALDH1 and PcALDH2) from the white-rot basidiomycete Phanerochaete chrysosporium. Both PcALDHs were translationally up-regulated in response to exogenous addition of vanillin, one of the key aromatic compounds in the pathway of lignin degradation by basidiomycetes. To clarify the catalytic functions of PcALDHs, we isolated full-length cDNAs encoding these proteins and heterologously expressed the recombinant enzymes using a pET/Escherichia coli system. The open reading frames of both PcALDH1 and PcALDH2 consisted of 1503 nucleotides. The deduced amino acid sequences of both proteins showed high homologies with aryl-aldehyde dehydrogenases from other organisms and contained ten conservedmore » domains of ALDHs. Moreover, a novel glycine-rich motif 'GxGxxxG' was located at the NAD{sup +}-binding site. The recombinant PcALDHs catalyzed dehydrogenation reactions of several aryl-aldehyde compounds, including vanillin, to their corresponding aromatic acids. These results strongly suggested that PcALDHs metabolize aryl-aldehyde compounds generated during fungal degradation of lignin and various aromatic xenobiotics.« less

  4. 5-ethynyl-2(1H)-pyrimidinone: aldehyde oxidase-activation to 5-ethynyluracil, a mechanism-based inactivator of dihydropyrimidine dehydrogenase.

    PubMed

    Porter, D J; Harrington, J A; Almond, M R; Lowen, G T; Zimmerman, T P; Spector, T

    1994-03-29

    5-Ethynyluracil is a potent mechanism-based inactivator of dihydropyrimidine dehydrogenase (DPD, EC 1.3.1.2) in vitro (Porter et al., J Biol Chem 267: 5236-5242, 1992) and in vivo (Spector et al., Biochem Pharmacol, 46: 2243-2248, 1993. 5-Ethynyl-2(1H)-pyrimidinone was rapidly oxidized to 5-ethynyluracil by aldehyde oxidase. The substrate efficiency (kcat/Km) was 60-fold greater than that for N-methylnicotinamide. In contrast, xanthine oxidase oxidized 5-ethynyl-2(1H)-pyrimidinone to 5-ethynyluracil with a substrate efficiency that was only 0.02% that of xanthine. Because 5-ethynyl-2(1H)-pyrimidinone did not itself inactivate purified DPD in vitro and aldehyde oxidase is predominately found in liver, we hypothesized that 5-ethynyl-2(1H)-pyrimidinone could be a liver-specific inactivator of DPD. We found that 5-ethynyl-2(1H)-pyrimidinone administered orally to rats at 2 micrograms/kg inactivated DPD in all tissues studied. Although 5-ethynyl-2(1H)-pyrimidinone produced slightly less inactivation than 5-ethynyluracil, the two compounds showed fairly similar patterns of inactivation of DPD in these tissues. At doses of 20 micrograms/kg, however, 5-ethynyl-2-pyrimidinone and 5-ethynyluracil produced equivalent inactivation of DPD. Thus, 5-ethynyl-2(1H)-pyrimidinone appeared to be an efficient, but not highly liver-selective prodrug of 5-ethynyluracil.

  5. Contribution of aldehyde oxidizing enzymes on the metabolism of 3,4-dimethoxy-2-phenylethylamine to 3,4-dimethoxyphenylacetic acid by guinea pig liver slices.

    PubMed

    Panoutsopoulos, Georgios I

    2006-01-01

    3,4-Dimethoxy-2-phenylethylamine is catalyzed to its aldehyde derivative by monoamine oxidase B, but the subsequent oxidation into the corresponding acid has not yet been studied. Oxidation of aromatic aldehydes is catalyzed mainly by aldehyde dehydrogenase and aldehyde oxidase. The present study examines the metabolism of 3,4-dimethoxy-2-phenylethylamine in vitro and in freshly prepared and cryopreserved guinea pig liver slices and the relative contribution of different aldehyde-oxidizing enzymes was estimated by pharmacological means. 3,4-Dimethoxy-2- phenylethylamine was converted into the corresponding aldehyde when incubated with monoamine oxidase and further oxidized into the acid when incubated with both, monoamine oxidase and aldehyde oxidase. In freshly prepared and cryopreserved liver slices, 3,4-dimethoxyphenylacetic acid was the main metabolite of 3,4-dimethoxy-2- phenylethylamine. 3,4-Dimethoxyphenylacetic acid formation was inhibited by 85% from disulfiram (aldehyde dehydrogenase inhibitor) and by 75-80% from isovanillin (aldehyde oxidase inhibitor), whereas allopurinol (xanthine oxidase inhibitor) inhibited acid formation by only 25-30%. 3,4- Dimethoxy-2-phenylethylamine is oxidized mainly to its acid, via 3,4-dimethoxyphenylacetaldehyde, by aldehyde dehydrogenase and aldehyde oxidase with a lower contribution from xanthine oxidase.

  6. Reversible, partial inactivation of plant betaine aldehyde dehydrogenase by betaine aldehyde: mechanism and possible physiological implications.

    PubMed

    Zárate-Romero, Andrés; Murillo-Melo, Darío S; Mújica-Jiménez, Carlos; Montiel, Carmina; Muñoz-Clares, Rosario A

    2016-04-01

    In plants, the last step in the biosynthesis of the osmoprotectant glycine betaine (GB) is the NAD(+)-dependent oxidation of betaine aldehyde (BAL) catalysed by some aldehyde dehydrogenase (ALDH) 10 enzymes that exhibit betaine aldehyde dehydrogenase (BADH) activity. Given the irreversibility of the reaction, the short-term regulation of these enzymes is of great physiological relevance to avoid adverse decreases in the NAD(+):NADH ratio. In the present study, we report that the Spinacia oleracea BADH (SoBADH) is reversibly and partially inactivated by BAL in the absence of NAD(+)in a time- and concentration-dependent mode. Crystallographic evidence indicates that the non-essential Cys(450)(SoBADH numbering) forms a thiohemiacetal with BAL, totally blocking the productive binding of the aldehyde. It is of interest that, in contrast to Cys(450), the catalytic cysteine (Cys(291)) did not react with BAL in the absence of NAD(+) The trimethylammonium group of BAL binds in the same position in the inactivating or productive modes. Accordingly, BAL does not inactivate the C(450)SSoBADH mutant and the degree of inactivation of the A(441)I and A(441)C mutants corresponds to their very different abilities to bind the trimethylammonium group. Cys(450)and the neighbouring residues that participate in stabilizing the thiohemiacetal are strictly conserved in plant ALDH10 enzymes with proven or predicted BADH activity, suggesting that inactivation by BAL is their common feature. Under osmotic stress conditions, this novel partial and reversible covalent regulatory mechanism may contribute to preventing NAD(+)exhaustion, while still permitting the synthesis of high amounts of GB and avoiding the accumulation of the toxic BAL. © 2016 Authors; published by Portland Press Limited.

  7. A bacterial aromatic aldehyde dehydrogenase critical for the efficient catabolism of syringaldehyde.

    PubMed

    Kamimura, Naofumi; Goto, Takayuki; Takahashi, Kenji; Kasai, Daisuke; Otsuka, Yuichiro; Nakamura, Masaya; Katayama, Yoshihiro; Fukuda, Masao; Masai, Eiji

    2017-03-15

    Vanillin and syringaldehyde obtained from lignin are essential intermediates for the production of basic chemicals using microbial cell factories. However, in contrast to vanillin, the microbial conversion of syringaldehyde is poorly understood. Here, we identified an aromatic aldehyde dehydrogenase (ALDH) gene responsible for syringaldehyde catabolism from 20 putative ALDH genes of Sphingobium sp. strain SYK-6. All these genes were expressed in Escherichia coli, and nine gene products, including previously characterized BzaA, BzaB, and vanillin dehydrogenase (LigV), exhibited oxidation activities for syringaldehyde to produce syringate. Among these genes, SLG_28320 (desV) and ligV were most highly and constitutively transcribed in the SYK-6 cells. Disruption of desV in SYK-6 resulted in a significant reduction in growth on syringaldehyde and in syringaldehyde oxidation activity. Furthermore, a desV ligV double mutant almost completely lost its ability to grow on syringaldehyde. Purified DesV showed similar k cat /K m values for syringaldehyde (2100 s -1 ·mM -1 ) and vanillin (1700 s -1 ·mM -1 ), whereas LigV substantially preferred vanillin (8800 s -1 ·mM -1 ) over syringaldehyde (1.4 s -1 ·mM -1 ). These results clearly demonstrate that desV plays a major role in syringaldehyde catabolism. Phylogenetic analyses showed that DesV-like ALDHs formed a distinct phylogenetic cluster separated from the vanillin dehydrogenase cluster.

  8. A bacterial aromatic aldehyde dehydrogenase critical for the efficient catabolism of syringaldehyde

    PubMed Central

    Kamimura, Naofumi; Goto, Takayuki; Takahashi, Kenji; Kasai, Daisuke; Otsuka, Yuichiro; Nakamura, Masaya; Katayama, Yoshihiro; Fukuda, Masao; Masai, Eiji

    2017-01-01

    Vanillin and syringaldehyde obtained from lignin are essential intermediates for the production of basic chemicals using microbial cell factories. However, in contrast to vanillin, the microbial conversion of syringaldehyde is poorly understood. Here, we identified an aromatic aldehyde dehydrogenase (ALDH) gene responsible for syringaldehyde catabolism from 20 putative ALDH genes of Sphingobium sp. strain SYK-6. All these genes were expressed in Escherichia coli, and nine gene products, including previously characterized BzaA, BzaB, and vanillin dehydrogenase (LigV), exhibited oxidation activities for syringaldehyde to produce syringate. Among these genes, SLG_28320 (desV) and ligV were most highly and constitutively transcribed in the SYK-6 cells. Disruption of desV in SYK-6 resulted in a significant reduction in growth on syringaldehyde and in syringaldehyde oxidation activity. Furthermore, a desV ligV double mutant almost completely lost its ability to grow on syringaldehyde. Purified DesV showed similar kcat/Km values for syringaldehyde (2100 s−1·mM−1) and vanillin (1700 s−1·mM−1), whereas LigV substantially preferred vanillin (8800 s−1·mM−1) over syringaldehyde (1.4 s−1·mM−1). These results clearly demonstrate that desV plays a major role in syringaldehyde catabolism. Phylogenetic analyses showed that DesV-like ALDHs formed a distinct phylogenetic cluster separated from the vanillin dehydrogenase cluster. PMID:28294121

  9. ALDH1A3, the Major Aldehyde Dehydrogenase Isoform in Human Cholangiocarcinoma Cells, Affects Prognosis and Gemcitabine Resistance in Cholangiocarcinoma Patients.

    PubMed

    Chen, Ming-Huang; Weng, Jing-Jie; Cheng, Chi-Tung; Wu, Ren-Chin; Huang, Shih-Chiang; Wu, Chiao-En; Chung, Yi-Hsiu; Liu, Chun-Yu; Chang, Mu-Hsin; Chen, Ming-Han; Chiang, Kun-Chun; Yeh, Ta-Sen; Su, Yeu; Yeh, Chun-Nan

    2016-08-15

    Intrahepatic cholangiocarcinoma is a fatal primary liver cancer resulting from diagnosis at an advanced stage. Understanding the mechanisms of drug resistance and metastasis of cholangiocarcinoma may improve the disease prognosis. Enhanced aldehyde dehydrogenase (ALDH) activity is suggested to be associated with increased drug resistance and the metastasis. This study aims to investigate the roles of the ALDH isoforms in cholangiocarcinoma. Aldefluor assays, RT-PCR, and Western blot analysis were used to identify the major ALDH isoforms contributing to Aldefluor activity in human cholangiocarcinoma cell lines. We manipulated isoform expression in HuCCT1 cells to elucidate the role of ALDH1A3 in the malignant progression of these cells. Finally, we used immunohistochemical staining to evaluate the clinical significance of ALDH1A3 in 77 hepatectomized cholangiocarcinoma patients and an additional 31 patients with advanced cholangiocarcinoma who received gemcitabine-based therapy. ALDH(high) cholangiocarcinoma cells not only migrated faster but were more resistant to gemcitabine. Among the 19 ALDH isoforms studied, ALDH1A3 was found to be the main contributor to Aldefluor activity. In addition, we also found that knockdown of ALDH1A3 expression in HuCCT1 cells markedly reduced not only their sensitivity to gemcitabine, which might be attributed to a decreased expression of ribonucleotide reductase M1, but also their migration. Most importantly, this enzyme was also identified as an independent poor prognostic factor for patients with intrahepatic cholangiocarcinoma, as well as a prognostic biomarker of gemcitabine-treated patients. ALDH1A3 plays an important role in enhancing malignant behavior of cholangiocarcinoma and serves as a new therapeutic target. Clin Cancer Res; 22(16); 4225-35. ©2016 AACR. ©2016 American Association for Cancer Research.

  10. Inhibition of human alcohol and aldehyde dehydrogenases by cimetidine and assessment of its effects on ethanol metabolism.

    PubMed

    Lai, Ching-Long; Li, Yeung-Pin; Liu, Chiu-Ming; Hsieh, Hsiu-Shan; Yin, Shih-Jiun

    2013-02-25

    Previous studies have reported that cimetidine, an H2-receptor antagonist used to treat gastric and duodenal ulcers, can inhibit alcohol dehydrogenases (ADHs) and ethanol metabolism. Human alcohol dehydrogenases and aldehyde dehydrogenases (ALDHs), the principal enzymes responsible for metabolism of ethanol, are complex enzyme families that exhibit functional polymorphisms among ethnic groups and distinct tissue distributions. We investigated the inhibition by cimetidine of alcohol oxidation by recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and aldehyde oxidation by ALDH1A1 and ALDH2 at pH 7.5 and a cytosolic NAD(+) concentration. Cimetidine acted as competitive or noncompetitive inhibitors for the ADH and ALDH isozymes/allozymes with near mM inhibition constants. The metabolic interactions between cimetidine and ethanol/acetaldehyde were assessed by computer simulation using the inhibition equations and the determined kinetic constants. At therapeutic drug levels (0.015 mM) and physiologically relevant concentrations of ethanol (10 mM) and acetaldehyde (10 μM) in target tissues, cimetidine could weakly inhibit (<5%) the activities of ADH1B2 and ADH1B3 in liver, ADH2 in liver and small intestine, ADH4 in stomach, and ALDH1A1 in the three tissues, but not significantly affect ADH1A, ADH1B1, ADH1C1/2, or ALDH2. At higher drug levels, which may accumulate in cells (0.2 mM), the activities of the weakly-inhibited enzymes may be decreased more significantly. The quantitative effects of cimetidine on metabolism of ethanol and other physiological substrates of ADHs need further investigation. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. The Activity of Class I-IV Alcohol Dehydrogenase Isoenzymes and Aldehyde Dehydrogenase in Bladder Cancer Cells.

    PubMed

    Orywal, Karolina; Jelski, Wojciech; Werel, Tadeusz; Szmitkowski, Maciej

    2018-01-02

    The aim of this study was to determine the differences in the activity of Alcohol Dehydrogenase (ADH) isoenzymes and Aldehyde Dehydrogenase (ALDH) in normal and cancerous bladder cells. Class III, IV of ADH and total ADH activity were measured by the photometric method and class I, II ADH and ALDH activity by the fluorometric method. Significantly higher total activity of ADH was found in both, low-grade and high-grade bladder cancer, in comparison to healthy tissues. The increased activity of total ADH in bladder cancer cells may be the cause of metabolic disorders in cancer cells, which may intensify carcinogenesis.

  12. Alcohol and aldehyde dehydrogenase polymorphisms in Chinese and Indian populations.

    PubMed

    Tan, Ene-Choo; Lim, Leslie; Leong, Jern-Yi; Lim, Jing-Yan; Lee, Arthur; Yang, Jun; Tan, Chay-Hoon; Winslow, Munidasa

    2010-01-01

    The association between two functional polymorphisms in alcohol dehydrogenase (ADH2/ADH1B) and aldehyde dehydrogenase (ALDH2) genes and alcohol dependence was examined in 182 Chinese and Indian patients undergoing treatment for alcohol dependence and 184 screened control subjects from Singapore. All subjects were screened by the Alcohol Use Disorders Identification Test (AUDIT). Patients were also administered the Severity of Alcohol Dependence Questionnaire (SADQ). Polymorphisms were genotyped by allele-specific polymerase chain reaction and selected genotypes confirmed by DNA sequencing or restriction fragment length polymorphism. Our results showed that frequencies of ADH1B*2 and ALDH2*2 were higher in controls compared to alcohol-dependent subjects for both Chinese and Indians. Frequencies of these two alleles were also higher in the 104 Chinese controls compared to the 80 Indian controls. None of the eight Chinese who were homozygous for both protective alleles was alcohol dependent. The higher frequencies of the protective alleles could explain the lower rate of alcohol dependence in Chinese.

  13. Depleted aldehyde dehydrogenase 1A1 (ALDH1A1) reverses cisplatin resistance of human lung adenocarcinoma cell A549/DDP.

    PubMed

    Wei, Yunyan; Wu, Shuangshuang; Xu, Wei; Liang, Yan; Li, Yue; Zhao, Weihong; Wu, Jianqing

    2017-01-01

    Cisplatin is the standard first-line chemotherapeutic agent for the treatment of non-small cell lung cancer (NSCLC). However, resistance to chemotherapy has been a major obstacle in the management of NSCLC. Aldehyde dehydrogenase 1A1 (ALDH1A1) overexpression has been observed in a variety of cancers, including lung cancer. The purpose of this study was to investigate the effect of ALDH1A1 expression on cisplatin resistance and explore the mechanism responsible. Reverse transcriptase-PCR was applied to measure the messenger RNA expression of ALDH1A1, while Western blot assay was employed to evaluate the protein expression of ALDH1A1, B-cell lymphoma 2, Bcl-2-like protein 4, phospho-protein kinase B (p-AKT) and AKT. A short hairpin RNA was used to knockdown ALDH1A1 expression. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to determine the effect of ALDH1A1 decrease on cell viability. The cell apoptotic rate was tested using flow cytometry assay. ALDH1A1 is overexpressed in cisplatin resistant cell line A549/DDP, compared with A549. ALDH1A1 depletion significantly decreased A549/DDP proliferation, increased apoptosis, and reduced cisplatin resistance. In addition, the phosphoinositide 3-kinase (PI3K) / AKT pathway is activated in A549/DDP, and ALDH1A1 knockdown reduced the phosphorylation level of AKT. Moreover, the combination of ALDH1A1-short hairpin RNA and PI3K/AKT pathway inhibitor LY294002 markedly inhibited cell viability, enhanced apoptotic cell death, and increased cisplatin sensitivity. These results suggest that ALDH1A1 depletion could reverse cisplatin resistance in human lung cancer cell line A549/DDP, and may act as a potential target for the treatment of lung cancers resistant to cisplatin. © 2016 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

  14. Betaine Aldehyde Dehydrogenase expression during physiological cardiac hypertrophy induced by pregnancy.

    PubMed

    Rosas-Rodríguez, Jesús Alfredo; Soñanez-Organis, José Guadalupe; Godoy-Lugo, José Arquimides; Espinoza-Salazar, Juan Alberto; López-Jacobo, Cesar Jeravy; Stephens-Camacho, Norma Aurora; González-Ochoa, Guadalupe

    2017-08-26

    Betaine Aldehyde Dehydrogenase (betaine aldehyde: NAD(P) + oxidoreductase, (E.C. 1.2.1.8; BADH) catalyze the irreversible oxidation of betaine aldehyde (BA) to glycine betaine (GB) and is essential for polyamine catabolism, γ-aminobutyric acid synthesis, and carnitine biosynthesis. GB is an important osmolyte that regulates the homocysteine levels, contributing to a vascular risk factor reduction. In this sense, distinct investigations describe the physiological roles of GB, but there is a lack of information about the GB novo synthesis process and regulation during cardiac hypertrophy induced by pregnancy. In this work, the BADH mRNA expression, protein level, and activity were quantified in the left ventricle before, during, and after pregnancy. The mRNA expression, protein content and enzyme activity along with GB content of BADH increased 2.41, 1.95 and 1.65-fold respectively during late pregnancy compared to not pregnancy, and returned to basal levels at postpartum. Besides, the GB levels increased 1.53-fold during pregnancy and remain at postpartum. Our results demonstrate that physiological cardiac hypertrophy induced BADH mRNA expression and activity along with GB production, suggesting that BADH participates in the adaptation process of physiological cardiac hypertrophy during pregnancy, according to the described GB role in cellular osmoregulation, osmoprotection and reduction of vascular risk. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Five Fatty Aldehyde Dehydrogenase Enzymes from Marinobacter and Acinetobacter spp. and Structural Insights into the Aldehyde Binding Pocket

    PubMed Central

    Bertram, Jonathan H.; Mulliner, Kalene M.; Shi, Ke; Plunkett, Mary H.; Nixon, Peter; Serratore, Nicholas A.; Douglas, Christopher J.; Aihara, Hideki

    2017-01-01

    ABSTRACT Enzymes involved in lipid biosynthesis and metabolism play an important role in energy conversion and storage and in the function of structural components such as cell membranes. The fatty aldehyde dehydrogenase (FAldDH) plays a central function in the metabolism of lipid intermediates, oxidizing fatty aldehydes to the corresponding fatty acid and competing with pathways that would further reduce the fatty aldehydes to fatty alcohols or require the fatty aldehydes to produce alkanes. In this report, the genes for four putative FAldDH enzymes from Marinobacter aquaeolei VT8 and an additional enzyme from Acinetobacter baylyi were heterologously expressed in Escherichia coli and shown to display FAldDH activity. Five enzymes (Maqu_0438, Maqu_3316, Maqu_3410, Maqu_3572, and the enzyme reported under RefSeq accession no. WP_004927398) were found to act on aldehydes ranging from acetaldehyde to hexadecanal and also acted on the unsaturated long-chain palmitoleyl and oleyl aldehydes. A comparison of the specificities of these enzymes with various aldehydes is presented. Crystallization trials yielded diffraction-quality crystals of one particular FAldDH (Maqu_3316) from M. aquaeolei VT8. Crystals were independently treated with both the NAD+ cofactor and the aldehyde substrate decanal, revealing specific details of the likely substrate binding pocket for this class of enzymes. A likely model for how catalysis by the enzyme is accomplished is also provided. IMPORTANCE This study provides a comparison of multiple enzymes with the ability to oxidize fatty aldehydes to fatty acids and provides a likely picture of how the fatty aldehyde and NAD+ are bound to the enzyme to facilitate catalysis. Based on the information obtained from this structural analysis and comparisons of specificities for the five enzymes that were characterized, correlations to the potential roles played by specific residues within the structure may be drawn. PMID:28389542

  16. Five Fatty Aldehyde Dehydrogenase Enzymes from Marinobacter and Acinetobacter spp. and Structural Insights into the Aldehyde Binding Pocket

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bertram, Jonathan H.; Mulliner, Kalene M.; Shi, Ke

    ABSTRACT Enzymes involved in lipid biosynthesis and metabolism play an important role in energy conversion and storage and in the function of structural components such as cell membranes. The fatty aldehyde dehydrogenase (FAldDH) plays a central function in the metabolism of lipid intermediates, oxidizing fatty aldehydes to the corresponding fatty acid and competing with pathways that would further reduce the fatty aldehydes to fatty alcohols or require the fatty aldehydes to produce alkanes. In this report, the genes for four putative FAldDH enzymes fromMarinobacter aquaeoleiVT8 and an additional enzyme fromAcinetobacter baylyiwere heterologously expressed inEscherichia coliand shown to display FAldDH activity.more » Five enzymes (Maqu_0438, Maqu_3316, Maqu_3410, Maqu_3572, and the enzyme reported under RefSeq accession no.WP_004927398) were found to act on aldehydes ranging from acetaldehyde to hexadecanal and also acted on the unsaturated long-chain palmitoleyl and oleyl aldehydes. A comparison of the specificities of these enzymes with various aldehydes is presented. Crystallization trials yielded diffraction-quality crystals of one particular FAldDH (Maqu_3316) fromM. aquaeoleiVT8. Crystals were independently treated with both the NAD +cofactor and the aldehyde substrate decanal, revealing specific details of the likely substrate binding pocket for this class of enzymes. A likely model for how catalysis by the enzyme is accomplished is also provided. IMPORTANCEThis study provides a comparison of multiple enzymes with the ability to oxidize fatty aldehydes to fatty acids and provides a likely picture of how the fatty aldehyde and NAD +are bound to the enzyme to facilitate catalysis. Based on the information obtained from this structural analysis and comparisons of specificities for the five enzymes that were characterized, correlations to the potential roles played by specific residues within the structure may be drawn.« less

  17. Aldehyde Dehydrogenase Plays a Pivotal Role in the Maintenance of Stallion Sperm Motility.

    PubMed

    Gibb, Zamira; Lambourne, Sarah R; Curry, Benjamin J; Hall, Sally E; Aitken, Robert J

    2016-06-01

    Although stallion spermatozoa produce significant quantities of reactive oxygen species, a lag between 4-hydroxynonenal (4HNE) adduction and the loss of motility in stallion spermatozoa suggests the presence of a robust aldehyde detoxification mechanism. Because there is a paucity of studies characterizing the role of aldehyde dehydrogenase (ALDH) in sperm functionality, the aim of this study was to ascertain the relationship between 4HNE production and motility and ALDH expression by stallion spermatozoa. PCR analysis revealed the presence of the ALDH1A3, ALDH1B1, and ALDH2 isoforms in these cells. Strong correlations (P < 0.001) were found between ALDH expression and various motility parameters of stallion spermatozoa including the percentage of progressive (r = 0.79) and rapidly motile (r = 0.79) spermatozoa, whereas repeated measurements over 24 h revealed highly significant correlations among progressive motility loss, 4HNE accumulation, and ALDH expression (P ≤ 0.001). ALDH inhibition resulted in a spontaneous increase in 4HNE levels in viable cells (21.1 ± 5.8% vs. 42.6 ± 5.2%; P ≤ 0.05) and a corresponding decrease in total motility (41.7 ± 6.2% vs. 6.4 ± 2.6%; P ≤ 0.001) and progressive motility (17.0 ± 4.1% vs. 0.7 ± 0.4%; P ≤ 0.001) of stallion spermatozoa over 24 h. Similarly, inhibition of ALDH in 4HNE-challenged spermatozoa significantly reduced total motility over 4 h (35.4 ± 9.7% vs. 15.3 ± 5.1%, respectively; P ≤ 0.05). This study contributes valuable information about the role of the ALDH enzymes in the maintenance of stallion sperm functionality, with potential diagnostic and in vitro applications for assisted reproductive technologies. © 2016 by the Society for the Study of Reproduction, Inc.

  18. Aldehyde Oxidase 4 Plays a Critical Role in Delaying Silique Senescence by Catalyzing Aldehyde Detoxification1[OPEN

    PubMed Central

    Yarmolinsky, Dmitry; Soltabayeva, Aigerim; Samani, Talya

    2017-01-01

    The Arabidopsis (Arabidopsis thaliana) aldehyde oxidases are a multigene family of four oxidases (AAO1–AAO4) that oxidize a variety of aldehydes, among them abscisic aldehyde, which is oxidized to the phytohormone abscisic acid. Toxic aldehydes are generated in plants both under normal conditions and in response to stress. The detoxification of such aldehydes by oxidation is attributed to aldehyde dehydrogenases but never to aldehyde oxidases. The feasibility of the detoxification of aldehydes in siliques via oxidation by AAO4 was demonstrated, first, by its ability to efficiently oxidize an array of aromatic and aliphatic aldehydes, including the reactive carbonyl species (RCS) acrolein, hydroxyl-2-nonenal, and malondialdehyde. Next, exogenous application of several aldehydes to siliques in AAO4 knockout (KO) Arabidopsis plants induced severe tissue damage and enhanced malondialdehyde levels and senescence symptoms, but not in wild-type siliques. Furthermore, abiotic stresses such as dark and ultraviolet C irradiation caused an increase in endogenous RCS and higher expression levels of senescence marker genes, leading to premature senescence of KO siliques, whereas RCS and senescence marker levels in wild-type siliques were hardly affected. Finally, in naturally senesced KO siliques, higher endogenous RCS levels were associated with enhanced senescence molecular markers, chlorophyll degradation, and earlier seed shattering compared with the wild type. The aldehyde-dependent differential generation of superoxide and hydrogen peroxide by AAO4 and the induction of AAO4 expression by hydrogen peroxide shown here suggest a self-amplification mechanism for detoxifying additional reactive aldehydes produced during stress. Taken together, our results indicate that AAO4 plays a critical role in delaying senescence in siliques by catalyzing aldehyde detoxification. PMID:28188272

  19. Kinetic properties of the human liver cytosolic aldehyde dehydrogenase for retinal isomers.

    PubMed

    Bhat, P V; Samaha, H

    1999-01-15

    Retinoic acid exerts pleiotropic effects by acting through two families of nuclear receptors, RAR and RXR. All-trans and 9-cis retinoic acid bind RARs, whereas 9-cis retinoic acid binds and activates only the RXRs. To understand the role of human liver cytosolic aldehyde dehydrogenase (ALDH1) in retinoic acid synthesis, we examined the ability of ALDH 1 to catalyze the oxidation of the naturally occurring retinal isomers. ALDH1 catalyzed the oxidation of all-trans, 9-cis, and 13-cis retinal with equal efficiency. However, the affinity to all-trans retinal (Km = 2.2 microM) was twofold higher than to 9-cis (Km = 5.5 microM) and 13-cis (Km = 4.6 microM) retinal. All-trans retinol was a potent inhibitor of ALDH1 activity, and inhibited all-trans retinal oxidation uncompetitively. Comparison of the kinetic properties of ALDH1 for retinal isomers with those of previously reported rat kidney retinal dehydrogenase showed distinct differences, suggesting that ALDH1 may play a different role in retinal metabolism in liver.

  20. The bifunctional alcohol and aldehyde dehydrogenase gene, adhE, is necessary for ethanol production in Clostridium thermocellum and Thermoanaerobacterium saccharolyticum.

    PubMed

    Lo, Jonathan; Zheng, Tianyong; Hon, Shuen; Olson, Daniel G; Lynd, Lee R

    2015-04-01

    Thermoanaerobacterium saccharolyticum and Clostridium thermocellum are anaerobic thermophilic bacteria being investigated for their ability to produce biofuels from plant biomass. The bifunctional alcohol and aldehyde dehydrogenase gene, adhE, is present in these bacteria and has been known to be important for ethanol formation in other anaerobic alcohol producers. This study explores the inactivation of the adhE gene in C. thermocellum and T. saccharolyticum. Deletion of adhE reduced ethanol production by >95% in both T. saccharolyticum and C. thermocellum, confirming that adhE is necessary for ethanol formation in both organisms. In both adhE deletion strains, fermentation products shifted from ethanol to lactate production and resulted in lower cell density and longer time to reach maximal cell density. In T. saccharolyticum, the adhE deletion strain lost >85% of alcohol dehydrogenase (ADH) activity. Aldehyde dehydrogenase (ALDH) activity did not appear to be affected, although ALDH activity was low in cell extracts. Adding ubiquinone-0 to the ALDH assay increased activity in the T. saccharolyticum parent strain but did not increase activity in the adhE deletion strain, suggesting that ALDH activity was inhibited. In C. thermocellum, the adhE deletion strain lost >90% of ALDH and ADH activity in cell extracts. The C. thermocellum adhE deletion strain contained a point mutation in the lactate dehydrogenase gene, which appears to deregulate its activation by fructose 1,6-bisphosphate, leading to constitutive activation of lactate dehydrogenase. Thermoanaerobacterium saccharolyticum and Clostridium thermocellum are bacteria that have been investigated for their ability to produce biofuels from plant biomass. They have been engineered to produce higher yields of ethanol, yet questions remain about the enzymes responsible for ethanol formation in these bacteria. The genomes of these bacteria encode multiple predicted aldehyde and alcohol dehydrogenases which could be

  1. Elucidating the contributions of multiple aldehyde/alcohol dehydrogenases to butanol and ethanol production in Clostridium acetobutylicum.

    PubMed

    Dai, Zongjie; Dong, Hongjun; Zhang, Yanping; Li, Yin

    2016-06-20

    Ethanol and butanol biosynthesis in Clostridium acetobutylicum share common aldehyde/alcohol dehydrogenases. However, little is known about the relative contributions of these multiple dehydrogenases to ethanol and butanol production respectively. The contributions of six aldehyde/alcohol dehydrogenases of C. acetobutylicum on butanol and ethanol production were evaluated through inactivation of the corresponding genes respectively. For butanol production, the relative contributions from these enzymes were: AdhE1 > BdhB > BdhA ≈ YqhD > SMB_P058 > AdhE2. For ethanol production, the contributions were: AdhE1 > BdhB > YqhD > SMB_P058 > AdhE2 > BdhA. AdhE1 and BdhB are two essential enzymes for butanol and ethanol production. AdhE1 was relatively specific for butanol production over ethanol, while BdhB, YqhD, and SMB_P058 favor ethanol production over butanol. Butanol synthesis was increased in the adhE2 mutant, which had a higher butanol/ethanol ratio (8.15:1) compared with wild type strain (6.65:1). Both the SMB_P058 mutant and yqhD mutant produced less ethanol without loss of butanol formation, which led to higher butanol/ethanol ratio, 10.12:1 and 10.17:1, respectively. To engineer a more efficient butanol-producing strain, adhE1 could be overexpressed, furthermore, adhE2, SMB_P058, yqhD are promising gene inactivation targets. This work provides useful information guiding future strain improvement for butanol production.

  2. Interaction of the SPG21 protein ACP33/maspardin with the aldehyde dehydrogenase ALDH16A1

    PubMed Central

    2017-01-01

    Mast syndrome (SPG21) is an autosomal-recessive complicated form of hereditary spastic paraplegia characterized by dementia, thin corpus callosum, white matter abnormalities, and cerebellar and extrapyramidal signs in addition to spastic paraparesis. A nucleotide insertion resulting in premature truncation of the SPG21 gene product acidic cluster protein 33 (ACP33)/maspardin underlies this disorder, likely causing loss of protein function. However, little is known about the function of maspardin. Here, we report that maspardin localizes prominently to cytoplasm as well as to membranes, possibly at trans-Golgi network/late endosomal compartments. Immunoprecipitation of maspardin with identification of coprecipitating proteins by mass spectrometry revealed the aldehyde dehydrogenase ALDH16A1 as an interacting protein. This interaction was confirmed using overexpressed proteins as well as by fusion protein pull down experiments, and these proteins colocalized in cells. Further studies of the function of ALDH16A1 and the role of the maspardin–ALDH16A1 interaction in neuronal cells may clarify the cellular pathogenesis of Mast syndrome. PMID:19184135

  3. The oxidative fermentation of ethanol in Gluconacetobacter diazotrophicus is a two-step pathway catalyzed by a single enzyme: alcohol-aldehyde Dehydrogenase (ADHa).

    PubMed

    Gómez-Manzo, Saúl; Escamilla, José E; González-Valdez, Abigail; López-Velázquez, Gabriel; Vanoye-Carlo, América; Marcial-Quino, Jaime; de la Mora-de la Mora, Ignacio; Garcia-Torres, Itzhel; Enríquez-Flores, Sergio; Contreras-Zentella, Martha Lucinda; Arreguín-Espinosa, Roberto; Kroneck, Peter M H; Sosa-Torres, Martha Elena

    2015-01-07

    Gluconacetobacter diazotrophicus is a N2-fixing bacterium endophyte from sugar cane. The oxidation of ethanol to acetic acid of this organism takes place in the periplasmic space, and this reaction is catalyzed by two membrane-bound enzymes complexes: the alcohol dehydrogenase (ADH) and the aldehyde dehydrogenase (ALDH). We present strong evidence showing that the well-known membrane-bound Alcohol dehydrogenase (ADHa) of Ga. diazotrophicus is indeed a double function enzyme, which is able to use primary alcohols (C2-C6) and its respective aldehydes as alternate substrates. Moreover, the enzyme utilizes ethanol as a substrate in a reaction mechanism where this is subjected to a two-step oxidation process to produce acetic acid without releasing the acetaldehyde intermediary to the media. Moreover, we propose a mechanism that, under physiological conditions, might permit a massive conversion of ethanol to acetic acid, as usually occurs in the acetic acid bacteria, but without the transient accumulation of the highly toxic acetaldehyde.

  4. The Oxidative Fermentation of Ethanol in Gluconacetobacter diazotrophicus Is a Two-Step Pathway Catalyzed by a Single Enzyme: Alcohol-Aldehyde Dehydrogenase (ADHa)

    PubMed Central

    Gómez-Manzo, Saúl; Escamilla, José E.; González-Valdez, Abigail; López-Velázquez, Gabriel; Vanoye-Carlo, América; Marcial-Quino, Jaime; de la Mora-de la Mora, Ignacio; Garcia-Torres, Itzhel; Enríquez-Flores, Sergio; Contreras-Zentella, Martha Lucinda; Arreguín-Espinosa, Roberto; Kroneck, Peter M. H.; Sosa-Torres, Martha Elena

    2015-01-01

    Gluconacetobacter diazotrophicus is a N2-fixing bacterium endophyte from sugar cane. The oxidation of ethanol to acetic acid of this organism takes place in the periplasmic space, and this reaction is catalyzed by two membrane-bound enzymes complexes: the alcohol dehydrogenase (ADH) and the aldehyde dehydrogenase (ALDH). We present strong evidence showing that the well-known membrane-bound Alcohol dehydrogenase (ADHa) of Ga. diazotrophicus is indeed a double function enzyme, which is able to use primary alcohols (C2–C6) and its respective aldehydes as alternate substrates. Moreover, the enzyme utilizes ethanol as a substrate in a reaction mechanism where this is subjected to a two-step oxidation process to produce acetic acid without releasing the acetaldehyde intermediary to the media. Moreover, we propose a mechanism that, under physiological conditions, might permit a massive conversion of ethanol to acetic acid, as usually occurs in the acetic acid bacteria, but without the transient accumulation of the highly toxic acetaldehyde. PMID:25574602

  5. AAV Gene Therapy for Alcoholism: Inhibition of Mitochondrial Aldehyde Dehydrogenase Enzyme Expression in Hepatoma Cells.

    PubMed

    Sanchez, Anamaria C; Li, Chengwen; Andrews, Barbara; Asenjo, Juan A; Samulski, R Jude

    2017-09-01

    Most ethanol is broken down in the liver in two steps by alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH2) enzymes, which metabolize down ethanol into acetaldehyde and then acetate. Some individuals from the Asian population who carry a mutation in the aldehyde dehydrogenase gene (ALDH2*2) cannot metabolize acetaldehyde as efficiently, producing strong effects, including facial flushing, dizziness, hypotension, and palpitations. This results in an aversion to alcohol intake and protection against alcoholism. The large prevalence of this mutation in the human population strongly suggests that modulation of ALDH2 expression by genetic technologies could result in a similar phenotype. scAAV2 vectors encoding ALDH2 small hairpin RNA (shRNA) were utilized to validate this hypothesis by silencing ALDH2 gene expression in human cell lines. Human cell lines HEK-293 and HepG2 were transduced with scAAV2/shRNA, showing a reduction in ALDH2 RNA and protein expression with the two viral concentration assayed (1 × 10 4 and 1 × 10 5 vg/cell) at two different time points. In both cell lines, ALDH2 RNA levels were reduced by 90% and protein expression was inhibited by 90% and 52%, respectively, 5 days post infection. Transduced HepG2 VL17A cells (ADH+) exposed to ethanol resulted in a 50% increase in acetaldehyde levels. These results suggest that gene therapy could be a useful tool for the treatment of alcoholism by knocking down ALDH2 expression using shRNA technology delivered by AAV vectors.

  6. Salivary aldehyde dehydrogenase - temporal and population variability, correlations with drinking and smoking habits and activity towards aldehydes contained in food.

    PubMed

    Giebułtowicz, Joanna; Dziadek, Marta; Wroczyński, Piotr; Woźnicka, Katarzyna; Wojno, Barbara; Pietrzak, Monika; Wierzchowski, Jacek

    2010-01-01

    Fluorimetric method based on oxidation of the fluorogenic 6-methoxy-2-naphthaldehyde was applied to evaluate temporal and population variability of the specific activity of salivary aldehyde dehydrogenase (ALDH) and the degree of its inactivation in healthy human population. Analyzed was also its dependence on drinking and smoking habits, coffee consumption, and its sensitivity to N-acetylcysteine. Both the specific activity of salivary ALDH and the degree of its inactivation were highly variable during the day, with the highest activities recorded in the morning hours. The activities were also highly variable both intra- and interpersonally, and negatively correlated with age, and this correlation was stronger for the subgroup of volunteers declaring abstinence from alcohol and tobacco. Moderately positive correlations of salivary ALDH specific activity with alcohol consumption and tobacco smoking were also recorded (r(s) ~0.27; p=0.004 and r(s) =0.30; p=0.001, respectively). Moderate coffee consumption correlated positively with the inactivation of salivary ALDH, particularly in the subgroup of non-drinking and non-smoking volunteers. It was found that mechanical stimulation of the saliva flow increases the specific activity of salivary ALDH. The specific activity of the salivary ALDH was strongly and positively correlated with that of superoxide dismutase, and somewhat less with salivary peroxidase. The antioxidant-containing drug N-acetylcysteine increased activity of salivary ALDH presumably by preventing its inactivation in the oral cavity. Some food-related aldehydes, mainly cinnamic aldehyde and anisaldehyde, were excellent substrates of the salivary ALDH3A1 enzyme, while alkenals, particularly those with short chain, were characterized by lower affinity towards this enzyme but high catalytic constants. The protective role of salivary ALDH against aldehydes in food and those found in the cigarette smoke is discussed, as well as its participation in

  7. Aldehyde dehydrogenase (ALDH) superfamily in plants: gene nomenclature and comparative genomics.

    PubMed

    Brocker, Chad; Vasiliou, Melpomene; Carpenter, Sarah; Carpenter, Christopher; Zhang, Yucheng; Wang, Xiping; Kotchoni, Simeon O; Wood, Andrew J; Kirch, Hans-Hubert; Kopečný, David; Nebert, Daniel W; Vasiliou, Vasilis

    2013-01-01

    In recent years, there has been a significant increase in the number of completely sequenced plant genomes. The comparison of fully sequenced genomes allows for identification of new gene family members, as well as comprehensive analysis of gene family evolution. The aldehyde dehydrogenase (ALDH) gene superfamily comprises a group of enzymes involved in the NAD(+)- or NADP(+)-dependent conversion of various aldehydes to their corresponding carboxylic acids. ALDH enzymes are involved in processing many aldehydes that serve as biogenic intermediates in a wide range of metabolic pathways. In addition, many of these enzymes function as 'aldehyde scavengers' by removing reactive aldehydes generated during the oxidative degradation of lipid membranes, also known as lipid peroxidation. Plants and animals share many ALDH families, and many genes are highly conserved between these two evolutionarily distinct groups. Conversely, both plants and animals also contain unique ALDH genes and families. Herein we carried out genome-wide identification of ALDH genes in a number of plant species-including Arabidopsis thaliana (thale crest), Chlamydomonas reinhardtii (unicellular algae), Oryza sativa (rice), Physcomitrella patens (moss), Vitis vinifera (grapevine) and Zea mays (maize). These data were then combined with previous analysis of Populus trichocarpa (poplar tree), Selaginella moellindorffii (gemmiferous spikemoss), Sorghum bicolor (sorghum) and Volvox carteri (colonial algae) for a comprehensive evolutionary comparison of the plant ALDH superfamily. As a result, newly identified genes can be more easily analyzed and gene names can be assigned according to current nomenclature guidelines; our goal is to clarify previously confusing and conflicting names and classifications that might confound results and prevent accurate comparisons between studies.

  8. Deficient expression of aldehyde dehydrogenase 1A1 is consistent with increased sensitivity of Gorlin syndrome patients to radiation carcinogenesis.

    PubMed

    Wright, Aaron T; Magnaldo, Thierry; Sontag, Ryan L; Anderson, Lindsey N; Sadler, Natalie C; Piehowski, Paul D; Gache, Yannick; Weber, Thomas J

    2015-06-01

    Human phenotypes that are highly susceptible to radiation carcinogenesis have been identified. Sensitive phenotypes often display robust regulation of molecular features that modify biological response, which can facilitate identification of the pathways/networks that contribute to pathophysiological outcomes. Here we interrogate primary dermal fibroblasts isolated from Gorlin syndrome patients (GDFs), who display a pronounced inducible tumorigenic response to radiation, in comparison to normal human dermal fibroblasts (NHDFs). Our approach exploits newly developed thiol reactive probes to define changes in protein thiol profiles in live cell studies, which minimizes artifacts associated with cell lysis. Redox probes revealed deficient expression of an apparent 55 kDa protein thiol in GDFs from independent Gorlin syndrome patients, compared with NHDFs. Proteomics tentatively identified this protein as aldehyde dehydrogenase 1A1 (ALDH1A1), a key enzyme regulating retinoic acid synthesis, and ALDH1A1 protein deficiency in GDFs was confirmed by Western blot. A number of additional protein thiol differences in GDFs were identified, including radiation responsive annexin family members and lamin A/C. Collectively, candidates identified in our study have plausible implications for radiation health effects and cancer susceptibility. © 2013 Wiley Periodicals, Inc.

  9. Aldehyde dehydrogenase polymorphism in North American, South American, and Mexican Indian populations.

    PubMed Central

    Goedde, H W; Agarwal, D P; Harada, S; Rothhammer, F; Whittaker, J O; Lisker, R

    1986-01-01

    While about 40% of the South American Indian populations (Atacameños, Mapuche, Shuara) were found to be deficient in aldehyde dehydrogenase isozyme I (ALDH2 or E2), preliminary investigations showed very low incidence of isozyme deficiency among North American natives (Sioux, Navajo) and Mexican Indians (mestizo). Possible implications of such trait differences on cross-cultural behavioral response to alcohol drinking are discussed. PMID:3953578

  10. Aldehyde dehydrogenase (ALDH) superfamily in plants: gene nomenclature and comparative genomics

    PubMed Central

    Brocker, Chad; Vasiliou, Melpomene; Carpenter, Sarah; Carpenter, Christopher; Zhang, Yucheng; Wang, Xiping; Kotchoni, Simeon O.; Wood, Andrew J.; Kirch, Hans-Hubert; Kopečný, David; Nebert, Daniel W.

    2012-01-01

    In recent years, there has been a significant increase in the number of completely sequenced plant genomes. The comparison of fully sequenced genomes allows for identification of new gene family members, as well as comprehensive analysis of gene family evolution. The aldehyde dehydrogenase (ALDH) gene superfamily comprises a group of enzymes involved in the NAD+- or NADP+-dependent conversion of various aldehydes to their corresponding carboxylic acids. ALDH enzymes are involved in processing many aldehydes that serve as biogenic intermediates in a wide range of metabolic pathways. In addition, many of these enzymes function as ‘aldehyde scavengers’ by removing reactive aldehydes generated during the oxidative degradation of lipid membranes, also known as lipid peroxidation. Plants and animals share many ALDH families, and many genes are highly conserved between these two evolutionarily distinct groups. Conversely, both plants and animals also contain unique ALDH genes and families. Herein we carried outgenome-wide identification of ALDH genes in a number of plant species—including Arabidopsis thaliana (thale crest), Chlamydomonas reinhardtii (unicellular algae), Oryza sativa (rice), Physcomitrella patens (moss), Vitis vinifera (grapevine) and Zea mays (maize). These data were then combined with previous analysis of Populus trichocarpa (poplar tree), Selaginella moellindorffii (gemmiferous spikemoss), Sorghum bicolor (sorghum) and Volvox carteri (colonial algae) for a comprehensive evolutionary comparison of the plant ALDH superfamily. As a result, newly identified genes can be more easily analyzed and gene names can be assigned according to current nomenclature guidelines; our goal is to clarify previously confusing and conflicting names and classifications that might confound results and prevent accurate comparisons between studies. PMID:23007552

  11. Lipoic acid protects gastric mucosa from ethanol-induced injury in rat through a mechanism involving aldehyde dehydrogenase 2 activation.

    PubMed

    Li, Jia-Hui; Ju, Gui-Xia; Jiang, Jun-Lin; Li, Nian-Sheng; Peng, Jun; Luo, Xiu-Ju

    2016-11-01

    Numerous studies demonstrate that reactive aldehydes are highly toxic and aldehyde dehydrogenase 2 (ALDH2)-mediated detoxification of reactive aldehydes is thought as an endogenous protective mechanism against reactive aldehydes-induced cell injury. This study aims to explore whether lipoic acid, a potential ALDH2 activator, is able to protect gastric mucosa from ethanol-induced injury through a mechanism involving clearance of reactive aldehydes. The rats received 60% of acidified ethanol through intragastric administration and held for 1 h to establish a mucosal injury model. Lipoic acid (10 or 30 mg/kg) or Alda-1 (a positive control, 10 mg/kg) was given 45 min before the ethanol treatment. The gastric tissues were collected for analysis of gastric ulcer index, cellular apoptosis, 4-hydroxy-2-nonenal (4-HNE) and malondialdehyde (MDA) contents, and ALDH2 activity. The results showed that acute administration of ethanol led to an increase in gastric ulcer index, cellular apoptosis, 4-HNE and MDA contents concomitant with a decrease in ALDH2 activity; these phenomena were reversed by lipoic acid or Alda-1. The gastric protection of lipoic acid was attenuated in the presence of ALDH2 inhibitor. Based on these observations, we conclude that lipoic acid exerts the beneficial effects on ethanol-induced injury through a mechanism involving, at least in part, ALDH2 activation. As a dietary supplement or a medicine already in some countries, lipoic acid can be used to treat the ethanol - induced gastric mucosal injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Age-dependent neurodegeneration accompanying memory loss in transgenic mice defective in mitochondrial aldehyde dehydrogenase 2 activity.

    PubMed

    Ohsawa, Ikuroh; Nishimaki, Kiyomi; Murakami, Yayoi; Suzuki, Yuko; Ishikawa, Masahiro; Ohta, Shigeo

    2008-06-11

    Oxidative stress may underlie age-dependent memory loss and cognitive decline. Toxic aldehydes, including 4-hydroxy-2-nonenal (HNE), an end product of lipid peroxides, are known to accumulate in the brain in neurodegenerative disease. We have previously shown that mitochondrial aldehyde dehydrogenase 2 (ALDH2) detoxifies HNE by oxidizing its aldehyde group. To investigate the role of such toxic aldehydes, we produced transgenic mice, which expressed a dominant-negative form of ALDH2 in the brain. The mice had decreased ability to detoxify HNE in their cortical neurons and accelerated accumulation of HNE in the brain. Consequently, their lifespan was shortened and age-dependent neurodegeneration and hyperphosphorylation of tau were observed. Object recognition and Morris water maze tests revealed that the onset of cognitive impairment correlated with the degeneration, which was further accelerated by APOE (apolipoprotein E) knock-out; therefore, the accumulation of toxic aldehydes is by itself critical in the progression of neurodegenerative disease, which could be suppressed by ALDH2.

  13. The aldehyde dehydrogenase, AldA, is essential for L-1,2-propanediol utilization in laboratory-evolved Escherichia coli.

    PubMed

    Aziz, Ramy K; Monk, Jonathan M; Andrews, Kathleen A; Nhan, Jenny; Khaw, Valerie L; Wong, Hesper; Palsson, Bernhard O; Charusanti, Pep

    2017-01-01

    Most Escherichia coli strains are naturally unable to grow on 1,2-propanediol (PDO) as a sole carbon source. Recently, however, a K-12 descendent E. coli strain was evolved to grow on 1,2-PDO, and it was hypothesized that this evolved ability was dependent on the aldehyde dehydrogenase, AldA, which is highly conserved among members of the family Enterobacteriacea. To test this hypothesis, we first performed computational model simulation, which confirmed the essentiality of the aldA gene for 1,2-PDO utilization by the evolved PDO-degrading E. coli. Next, we deleted the aldA gene from the evolved strain, and this deletion was sufficient to abolish the evolved phenotype. On re-introducing the gene on a plasmid, the evolved phenotype was restored. These findings provide experimental evidence for the computationally predicted role of AldA in 1,2-PDO utilization, and represent a good example of E. coli robustness, demonstrated by the bacterial deployment of a generalist enzyme (here AldA) in multiple pathways to survive carbon starvation and to grow on a non-native substrate when no native carbon source is available. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Sequence of the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Nicotiana plumbaginifolia and phylogenetic origin of the gene family.

    PubMed

    Habenicht, A; Quesada, A; Cerff, R

    1997-10-01

    A cDNA-library has been constructed from Nicotiana plumbaginifolia seedlings, and the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase (GapN, EC 1.2.1.9) was isolated by plaque hybridization using the cDNA from pea as a heterologous probe. The cDNA comprises the entire GapN coding region. A putative polyadenylation signal is identified. Phylogenetic analysis based on the deduced amino acid sequences revealed that the GapN gene family represents a separate ancient branch within the aldehyde dehydrogenase superfamily. It can be shown that the GapN gene family and other distinct branches of the superfamily have its phylogenetic origin before the separation of primary life-forms. This further demonstrates that already very early in evolution, a broad diversification of the aldehyde dehydrogenases led to the formation of the superfamily.

  15. Aldehyde Dehydrogenase 2 in Aplastic Anemia, Fanconi Anemia and Hematopoietic Stem Cells

    PubMed Central

    Van Wassenhove, Lauren D.; Mochly-Rosen, Daria; Weinberg, Kenneth I.

    2016-01-01

    Maintenance of the hematopoietic stem cell (HSC) compartment depends on the ability to metabolize exogenously and endogenously generated toxins, and to repair cellular damage caused by such toxins. Reactive aldehydes have been demonstrated to cause specific genotoxic injury, namely DNA interstrand cross-links. Aldehyde dehydrogenase 2 (ALDH2) is a member of a 19 isoenzyme ALDH family with different substrate specificities, subcellular localization, and patterns of expression. ALDH2 is localized in mitochondria and is essential for the metabolism of acetaldehyde, thereby placing it directly downstream of ethanol metabolism. Deficiency in ALDH2 expression and function are caused by a single nucleotide substitution and resulting amino acid change, called ALDH2*2. This genetic polymorphism affects 35–45% of East Asians (about ~560 million people), and causes the well-known Asian flushing syndrome, which results in disulfiram-like reactions after ethanol consumption. Recently, the ALDH2*2 genotype has been found to be associated with marrow failure, with both an increased risk of sporadic aplastic anemia and more rapid progression of Fanconi Anemia. This review discusses the unexpected interrelationship between aldehydes, ALDH2 and hematopoietic stem cell biology, and in particular its relationship to Fanconi anemia. PMID:27650066

  16. Aldehyde dehydrogenase inhibition as a pathogenic mechanism in Parkinson disease

    PubMed Central

    Fitzmaurice, Arthur G.; Rhodes, Shannon L.; Lulla, Aaron; Murphy, Niall P.; Lam, Hoa A.; O’Donnell, Kelley C.; Barnhill, Lisa; Casida, John E.; Cockburn, Myles; Sagasti, Alvaro; Stahl, Mark C.; Maidment, Nigel T.; Ritz, Beate; Bronstein, Jeff M.

    2013-01-01

    Parkinson disease (PD) is a neurodegenerative disorder particularly characterized by the loss of dopaminergic neurons in the substantia nigra. Pesticide exposure has been associated with PD occurrence, and we previously reported that the fungicide benomyl interferes with several cellular processes potentially relevant to PD pathogenesis. Here we propose that benomyl, via its bioactivated thiocarbamate sulfoxide metabolite, inhibits aldehyde dehydrogenase (ALDH), leading to accumulation of the reactive dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL), preferential degeneration of dopaminergic neurons, and development of PD. This hypothesis is supported by multiple lines of evidence. (i) We previously showed in mice the metabolism of benomyl to S-methyl N-butylthiocarbamate sulfoxide, which inhibits ALDH at nanomolar levels. We report here that benomyl exposure in primary mesencephalic neurons (ii) inhibits ALDH and (iii) alters dopamine homeostasis. It induces selective dopaminergic neuronal damage (iv) in vitro in primary mesencephalic cultures and (v) in vivo in a zebrafish system. (vi) In vitro cell loss was attenuated by reducing DOPAL formation. (vii) In our epidemiology study, higher exposure to benomyl was associated with increased PD risk. This ALDH model for PD etiology may help explain the selective vulnerability of dopaminergic neurons in PD and provide a potential mechanism through which environmental toxicants contribute to PD pathogenesis. PMID:23267077

  17. Characterization of aldehyde dehydrogenase 1 high ovarian cancer cells: Towards targeted stem cell therapy.

    PubMed

    Sharrow, Allison C; Perkins, Brandy; Collector, Michael I; Yu, Wayne; Simons, Brian W; Jones, Richard J

    2016-08-01

    The cancer stem cell (CSC) paradigm hypothesizes that successful clinical eradication of CSCs may lead to durable remission for patients with ovarian cancer. Despite mounting evidence in support of ovarian CSCs, their phenotype and clinical relevance remain unclear. We and others have found high aldehyde dehydrogenase 1 (ALDH(high)) expression in a variety of normal and malignant stem cells, and sought to better characterize ALDH(high) cells in ovarian cancer. We compared ALDH(high) to ALDH(low) cells in two ovarian cancer models representing distinct subtypes: FNAR-C1 cells, derived from a spontaneous rat endometrioid carcinoma, and the human SKOV3 cell line (described as both serous and clear cell subtypes). We assessed these populations for stem cell features then analyzed expression by microarray and qPCR. ALDH(high) cells displayed CSC properties, including: smaller size, quiescence, regenerating the phenotypic diversity of the cell lines in vitro, lack of contact inhibition, nonadherent growth, multi-drug resistance, and in vivo tumorigenicity. Microarray and qPCR analysis of the expression of markers reported by others to enrich for ovarian CSCs revealed that ALDH(high) cells of both models showed downregulation of CD24, but inconsistent expression of CD44, KIT and CD133. However, the following druggable targets were consistently expressed in the ALDH(high) cells from both models: mTOR signaling, her-2/neu, CD47 and FGF18/FGFR3. Based on functional characterization, ALDH(high) ovarian cancer cells represent an ovarian CSC population. Differential gene expression identified druggable targets that have the potential for therapeutic efficacy against ovarian CSCs from multiple subtypes. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Badh2, Encoding Betaine Aldehyde Dehydrogenase, Inhibits the Biosynthesis of 2-Acetyl-1-Pyrroline, a Major Component in Rice Fragrance[W

    PubMed Central

    Chen, Saihua; Yang, Yi; Shi, Weiwei; Ji, Qing; He, Fei; Zhang, Ziding; Cheng, Zhukuan; Liu, Xiangnong; Xu, Mingliang

    2008-01-01

    In rice (Oryza sativa), the presence of a dominant Badh2 allele encoding betaine aldehyde dehydrogenase (BADH2) inhibits the synthesis of 2-acetyl-1-pyrroline (2AP), a potent flavor component in rice fragrance. By contrast, its two recessive alleles, badh2-E2 and badh2-E7, induce 2AP formation. Badh2 was found to be transcribed in all tissues tested except for roots, and the transcript was detected at higher abundance in young, healthy leaves than in other tissues. Multiple Badh2 transcript lengths were detected, and the complete, full-length Badh2 transcript was much less abundant than partial Badh2 transcripts. 2AP levels were significantly reduced in cauliflower mosaic virus 35S-driven transgenic lines expressing the complete, but not the partial, Badh2 coding sequences. In accordance, the intact, full-length BADH2 protein (503 residues) appeared exclusively in nonfragrant transgenic lines and rice varieties. These results indicate that the full-length BADH2 protein encoded by Badh2 renders rice nonfragrant by inhibiting 2AP biosynthesis. The BADH2 enzyme was predicted to contain three domains: NAD binding, substrate binding, and oligomerization domains. BADH2 was distributed throughout the cytoplasm, where it is predicted to catalyze the oxidization of betaine aldehyde, 4-aminobutyraldehyde (AB-ald), and 3-aminopropionaldehyde. The presence of null badh2 alleles resulted in AB-ald accumulation and enhanced 2AP biosynthesis. In summary, these data support the hypothesis that BADH2 inhibits 2AP biosynthesis by exhausting AB-ald, a presumed 2AP precursor. PMID:18599581

  19. ALD5, PAD1, ATF1 and ATF2 facilitate the catabolism of coniferyl aldehyde, ferulic acid and p-coumaric acid in Saccharomyces cerevisiae

    PubMed Central

    Adeboye, Peter Temitope; Bettiga, Maurizio; Olsson, Lisbeth

    2017-01-01

    The ability of Saccharomyces cerevisiae to catabolize phenolic compounds remains to be fully elucidated. Conversion of coniferyl aldehyde, ferulic acid and p-coumaric acid by S. cerevisiae under aerobic conditions was previously reported. A conversion pathway was also proposed. In the present study, possible enzymes involved in the reported conversion were investigated. Aldehyde dehydrogenase Ald5, phenylacrylic acid decarboxylase Pad1, and alcohol acetyltransferases Atf1 and Atf2, were hypothesised to be involved. Corresponding genes for the four enzymes were overexpressed in a S. cerevisiae strain named APT_1. The ability of APT_1 to tolerate and convert the three phenolic compounds was tested. APT_1 was also compared to strains B_CALD heterologously expressing coniferyl aldehyde dehydrogenase from Pseudomonas, and an ald5Δ strain, all previously reported. APT_1 exhibited the fastest conversion of coniferyl aldehyde, ferulic acid and p-coumaric acid. Using the intermediates and conversion products of each compound, the catabolic route of coniferyl aldehyde, ferulic acid and p-coumaric acid in S. cerevisiae was studied in greater detail. PMID:28205618

  20. Aldehyde dehydrogenase 2 in aplastic anemia, Fanconi anemia and hematopoietic stem cells.

    PubMed

    Van Wassenhove, Lauren D; Mochly-Rosen, Daria; Weinberg, Kenneth I

    2016-09-01

    Maintenance of the hematopoietic stem cell (HSC) compartment depends on the ability to metabolize exogenously and endogenously generated toxins, and to repair cellular damage caused by such toxins. Reactive aldehydes have been demonstrated to cause specific genotoxic injury, namely DNA interstrand cross-links. Aldehyde dehydrogenase 2 (ALDH2) is a member of a 19 isoenzyme ALDH family with different substrate specificities, subcellular localization, and patterns of expression. ALDH2 is localized in mitochondria and is essential for the metabolism of acetaldehyde, thereby placing it directly downstream of ethanol metabolism. Deficiency in ALDH2 expression and function are caused by a single nucleotide substitution and resulting amino acid change, called ALDH2*2. This genetic polymorphism affects 35-45% of East Asians (about ~560 million people), and causes the well-known Asian flushing syndrome, which results in disulfiram-like reactions after ethanol consumption. Recently, the ALDH2*2 genotype has been found to be associated with marrow failure, with both an increased risk of sporadic aplastic anemia and more rapid progression of Fanconi anemia. This review discusses the unexpected interrelationship between aldehydes, ALDH2 and hematopoietic stem cell biology, and in particular its relationship to Fanconi anemia. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Spectroscopic characterisation of interaction of ferulic acid with aldehyde dehydrogenase (ALDH).

    PubMed

    Kolawole, Ayodele O; Agaba, Ruth J; Oluwole, Matthew O

    2017-05-01

    Interaction of a pharmacological important phenolic, ferulic acid, with Aldehyde dehydrogenase (ALDH) at the simulative pH condition, was studied using spectroscopic approach. Ferulic acid caused a decrease in the fluorescence intensity formed from ALDH-ferulic acid complex resulting in mixed inhibition of ALDH activity (IC 50 =30.65μM). The intrinsic quenching was dynamic and induced altered conformation of ALDH and made the protein less compact but might not unfold it. ALDH has two binding sites for ferulic acid at saturating concentrations having association constant of 1.35×10 3 Lmol -1 and a dissociation constant of 9.7×10 7 Lmol -1 at 25°C indicating ALDH-ferulic acid complex formation is more favourable than its dissociation. The interaction was not spontaneous and endothermic and suggests the involvement of hydrophobic interactions with a FRET binding distance of 4.49nm. Change in pH near and far from isoelectric points of ferulic acid did not affect the bonding interaction. Using trehalose as viscosogen, the result from Stoke-Einstein hypothesis showed that ferulic acid-ALDH binding and dissociation equilibrium was diffusion controlled. These results clearly suggest the unique binding properties and lipophilicity influence of ferulic acid. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. HEPATOCYTE EXPRESION OF TUMOR ASSOCIATED ALDEHYDE DEHYDROGENASE (ALDH-3) AND P21 RAS FOLLOWING DIETHYLNITROSAMINE (DEN) INITIATION AND CHRONIC EXPOSURE TO DI(2-ETHYLHEXYL) PHTHALATE (DHEP)

    EPA Science Inventory

    Phthalate esters such as di(2-ethylhexyl)phthalate (DEHP)either promote or inhibit rat liver tumorigenesis depending on the carcinogenesis protocol. In this study, we examined the expression of two histochemical markers, the tumor associated isozyme of aldehyde dehydrogenase (ALD...

  3. Steady-state kinetic mechanism of the NADP+- and NAD+-dependent reactions catalysed by betaine aldehyde dehydrogenase from Pseudomonas aeruginosa.

    PubMed Central

    Velasco-García, R; González-Segura, L; Muñoz-Clares, R A

    2000-01-01

    Betaine aldehyde dehydrogenase (BADH) catalyses the irreversible oxidation of betaine aldehyde to glycine betaine with the concomitant reduction of NAD(P)(+) to NADP(H). In Pseudomonas aeruginosa this reaction is a compulsory step in the assimilation of carbon and nitrogen when bacteria are growing in choline or choline precursors. The kinetic mechanisms of the NAD(+)- and NADP(+)-dependent reactions were examined by steady-state kinetic methods and by dinucleotide binding experiments. The double-reciprocal patterns obtained for initial velocity with NAD(P)(+) and for product and dead-end inhibition establish that both mechanisms are steady-state random. However, quantitative analysis of the inhibitions, and comparison with binding data, suggest a preferred route of addition of substrates and release of products in which NAD(P)(+) binds first and NAD(P)H leaves last, particularly in the NADP(+)-dependent reaction. Abortive binding of the dinucleotides, or their analogue ADP, in the betaine aldehyde site was inferred from total substrate inhibition by the dinucleotides, and parabolic inhibition by NADH and ADP. A weak partial uncompetitive substrate inhibition by the aldehyde was observed only in the NADP(+)-dependent reaction. The kinetics of P. aeruginosa BADH is very similar to that of glucose-6-phosphate dehydrogenase, suggesting that both enzymes fulfil a similar amphibolic metabolic role when the bacteria grow in choline and when they grow in glucose. PMID:11104673

  4. High aldehyde dehydrogenase activity identifies cancer stem cells in human cervical cancer

    PubMed Central

    Liu, Shu-Yan; Zheng, Peng-Sheng

    2013-01-01

    High aldehyde dehydrogenase (ALDH) activity characterizes a subpopulation of cells with cancer stem cell (CSC) properties in several malignancies. To clarify whether ALDH can be used as a marker of cervical cancer stem cells (CCSCs), ALDHhigh and ALDHlow cells were sorted from 4 cervical cancer cell lines and 5 primary tumor xenografts and examined for CSC characteristics. Here, we demonstrate that cervical cancer cells with high ALDH activity fulfill the functional criteria for CSCs: (1) ALDHhigh cells, unlike ALDHlow cells, are highly tumorigenic in vivo; (2) ALDHhigh cells can give rise to both ALDHhigh and ALDHlow cells in vitro and in vivo, thereby establishing a cellular hierarchy; and (3) ALDHhigh cells have enhanced self-renewal and differentiation potentials. Additionally, ALDHhigh cervical cancer cells are more resistant to cisplatin treatment than ALDHlow cells. Finally, expression of the stem cell self-renewal-associated transcription factors OCT4, NANOG, KLF4 and BMI1 is elevated in ALDHhigh cervical cancer cells. Taken together, our data indicated that high ALDH activity may represent both a functional marker for CCSCs and a target for novel cervical cancer therapies. PMID:24318570

  5. Aldehyde dehydrogenase inhibition blocks mucosal fibrosis in human and mouse ocular scarring

    PubMed Central

    Ahadome, Sarah D.; Abraham, David J.; Rayapureddi, Suryanarayana; Saw, Valerie P.; Saban, Daniel R.; Calder, Virginia L.; Norman, Jill T.; Ponticos, Markella; Daniels, Julie T.; Dart, John K.

    2016-01-01

    Mucous membrane pemphigoid (MMP) is a systemic mucosal scarring disease, commonly causing blindness, for which there is no antifibrotic therapy. Aldehyde dehydrogenase family 1 (ALDH1) is upregulated in both ocular MMP (OMMP) conjunctiva and cultured fibroblasts. Application of the ALDH metabolite, retinoic acid (RA), to normal human conjunctival fibroblasts in vitro induced a diseased phenotype. Conversely, application of ALDH inhibitors, including disulfiram, to OMMP fibroblasts in vitro restored their functionality to that of normal controls. ALDH1 is also upregulated in the mucosa of the mouse model of scarring allergic eye disease (AED), used here as a surrogate for OMMP, in which topical application of disulfiram decreased fibrosis in vivo. These data suggest that progressive scarring in OMMP results from ALDH/RA fibroblast autoregulation, that the ALDH1 subfamily has a central role in immune-mediated ocular mucosal scarring, and that ALDH inhibition with disulfiram is a potential and readily translatable antifibrotic therapy. PMID:27699226

  6. Fatty Aldehydes in Cyanobacteria Are a Metabolically Flexible Precursor for a Diversity of Biofuel Products

    PubMed Central

    Kaiser, Brett K.; Carleton, Michael; Hickman, Jason W.; Miller, Cameron; Lawson, David; Budde, Mark; Warrener, Paul; Paredes, Angel; Mullapudi, Srinivas; Navarro, Patricia; Cross, Fred; Roberts, James M.

    2013-01-01

    We describe how pathway engineering can be used to convert a single intermediate derived from lipid biosynthesis, fatty aldehydes, into a variety of biofuel precursors including alkanes, free fatty acids and wax esters. In cyanobacteria, long-chain acyl-ACPs can be reduced to fatty aldehydes, and then decarbonylated to alkanes. We discovered a cyanobacteria class-3 aldehyde-dehydrogenase, AldE, that was necessary and sufficient to instead oxidize fatty aldehyde precursors into fatty acids. Overexpression of enzymes in this pathway resulted in production of 50 to 100 fold more fatty acids than alkanes, and the fatty acids were secreted from the cell. Co-expression of acyl-ACP reductase, an alcohol-dehydrogenase and a wax-ester-synthase resulted in a third fate for fatty aldehydes: conversion to wax esters, which accumulated as intracellular lipid bodies. Conversion of acyl-ACP to fatty acids using endogenous cyanobacterial enzymes may allow biofuel production without transgenesis. PMID:23505484

  7. RNAi-directed downregulation of betaine aldehyde dehydrogenase 1 (OsBADH1) results in decreased stress tolerance and increased oxidative markers without affecting glycine betaine biosynthesis in rice (Oryza sativa).

    PubMed

    Tang, Wei; Sun, Jiaqi; Liu, Jia; Liu, Fangfang; Yan, Jun; Gou, Xiaojun; Lu, Bao-Rong; Liu, Yongsheng

    2014-11-01

    As an important osmoprotectant, glycine betaine (GB) plays an essential role in resistance to abiotic stress in a variety of organisms, including rice (Oryza sativa L.). However, GB content is too low to be detectable in rice, although rice genome possesses several orthologs coding for betaine aldehyde dehydrogenase (BADH) involved in plant GB biosynthesis. Rice BADH1 (OsBADH1) has been shown to be targeted to peroxisome and its overexpression resulted in increased GB biosynthesis and tolerance to abiotic stress. In this study, we demonstrated a pivotal role of OsBADH1 in stress tolerance without altering GB biosynthesis capacity, using the RNA interference (RNAi) technique. OsBADH1 was ubiquitously expressed in different organs, including roots, stems, leaves and flowers. Transgenic rice lines downregulating OsBADH1 exhibited remarkably reduced tolerance to NaCl, drought and cold stresses. The decrease of stress tolerance occurring in the OsBADH1-RNAi repression lines was associated with an elevated level of malondialdehyde content and hydrogen peroxidation. No GB accumulation was detected in transgene-positive and transgene-negative lines derived from heterozygous transgenic T0 plants. Moreover, transgenic OsBADH1-RNAi repression lines showed significantly reduced seed set and yield. In conclusion, the downregulation of OsBADH1, even though not causing any change of GB content, was accounted for the reduction of ability to dehydrogenate the accumulating metabolism-derived aldehydes and subsequently resulted in decreased stress tolerance and crop productivity. These results suggest that OsBADH1 possesses an enzyme activity to catalyze other aldehydes in addition to betaine aldehyde (the precursor of GB) and thus alleviate their toxic effects under abiotic stresses.

  8. Kinetic and biophysical investigation of the inhibitory effect of caffeine on human salivary aldehyde dehydrogenase: Implications in oral health and chemotherapy

    NASA Astrophysics Data System (ADS)

    Laskar, Amaj Ahmed; Alam, Md Fazle; Ahmad, Mohammad; Younus, Hina

    2018-04-01

    Human salivary aldehyde dehydrogenase (hsALDH) is primarily a class 3 ALDH (ALDH3A1), and is an important antioxidant enzyme present in the saliva which maintains healthy oral cavity. It detoxifies toxic aldehydes into non-toxic carboxylic acids in the oral cavity. Reduced level of hsALDH activity is a risk factor for oral cancer development. It is involved in the resistance of certain chemotherapeutic drugs. Coffee has been reported to affect the activity of salivary ALDH. In this study, the effect of caffeine on the activity (dehydrogenase and esterase) of hsALDH was investigated. The binding of caffeine to hsALDH was studied using different biophysical methods and molecular docking analysis. Caffeine was found to inhibit both crude and purified hsALDH. The Km increased and the Vmax decreased showing a mixed type of inhibition. Caffeine decreased the nucleophilicity of the catalytic cysteine residue. It binds to the active site of ALDH3A1 by forming a complex through non-covalent interactions with some highly conserved amino acid residues. It partially alters the secondary structure of the enzyme. Therefore, it is very likely that caffeine binds and inhibits the activity of hsALDH by decreasing substrate binding affinity and the catalytic efficiency of the enzyme. The study indicates that oral intake of caffeine may have a harmful effect on the oral health and may increase the risk of carcinogenesis through the inhibition of this important enzyme. Further, the inactivation of oxazaphosphorine based chemotherapeutic drugs by ALDH3A1 may be prevented by using caffeine as an adjuvant during medication which is expected to increase the sensitivity of these drugs through its inhibitory effect on the enzyme.

  9. Aldehyde dehydrogenase 2 activation in aged heart improves the autophagy by reducing the carbonyl modification on SIRT1.

    PubMed

    Wu, Bing; Yu, Lu; Wang, Yishi; Wang, Hongtao; Li, Chen; Yin, Yue; Yang, Jingrun; Wang, Zhifa; Zheng, Qiangsun; Ma, Heng

    2016-01-19

    Cardiac aging is characterized by accumulation of damaged proteins and decline of autophagic efficiency. Here, by forestalling SIRT1 carbonylated inactivation in aged heart, we determined the benefits of activation of aldehyde dehydrogenase 2 (ALDH2) on the autophagy. In this study, the ALDH2 KO mice progressively developed age-related heart dysfunction and showed reduction in the life span, which strongly suggests that ALDH2 ablation leads to cardiac aging. What's more, aged hearts displayed a significant decrease ALDH2 activity, resulting in accumulation of 4-HNE-protein adducts and protein carbonyls, impairment in the autophagy flux, and, consequently, deteriorated cardiac function after starvation. Sustained Alda-1 (selective ALDH2 activator) treatment increased cardiac ALDH2 activity and abrogated these effects. Using SIRT1 deficient heterozygous (Sirt1+/-) mice, we found that SIRT1 was necessary for ALDH2 activation-induced autophagy. We further demonstrated that ALDH2 activation attenuated SIRT1 carbonylation and improved SIRT1 activity, thereby increasing the deacetylation of nuclear LC3 and FoxO1. Sequentially, ALDH2 enhanced SIRT1 regulates LC3-Atg7 interaction and FoxO1 increased Rab7 expression, which were both necessary and sufficient for restoring autophagy flux. These results highlight that both accumulation of proteotoxic carbonyl stress linkage with autophagy decline contribute to heart senescence. ALDH2 activation is adequate to improve the autophagy flux by reducing the carbonyl modification on SIRT1, which in turn plays an important role in maintaining cardiac health during aging.

  10. Deficient expression of aldehyde dehydrogenase 1A1 is consistent with increased sensitivity of Gorlin syndrome patients to radiation carcinogenesis

    DOE PAGES

    Wright, Aaron T.; Magnaldo, Thierry; Sontag, Ryan L.; ...

    2013-11-27

    Human phenotypes that are highly susceptible to radiation carcinogenesis have been identified. Sensitive phenotypes often display robust regulation of molecular features that modify biological response, which can facilitate identification of relevant pathways/networks. Here we interrogate primary dermal fibroblasts isolated from Gorlin syndrome patients (GDFs), who display a pronounced tumorigenic response to radiation, in comparison to normal human dermal fibroblasts (NHDFs). Our approach exploits newly developed thiol-reactive probes with a flexible click chemistry functional group to define changes in protein thiol profiles in live cell studies, which minimizes artifacts associated with cell lysis. We observe qualitative differences in protein thiol profilesmore » by SDS-PAGE analysis when detection by iodoacetamide vs maleimide probe chemistries are compared, and pretreatment of cells with hydrogen peroxide eliminates detection of the majority of SDS-PAGE bands. Redox probes revealed deficient expression of an apparent 55 kDa protein thiol in GDFs from independent donors, compared with NHDFs. Proteomics tentatively identified this protein as aldehyde dehydrogenase 1A1 (ALDH1A1), a key enzyme regulating retinoic acid synthesis, and this deficiency was confirmed by Western blot. Redox probes revealed additional protein thiol differences between GDFs and NHDFs, including radiation responsive annexin family members. Our results indicate a multifactorial basis for the unusual sensitivity of Gorlin syndrome to radiation carcinogenesis, and the pathways identified have plausible implications for radiation health effects.« less

  11. Deficient expression of aldehyde dehydrogenase 1A1 is consistent with increased sensitivity of Gorlin syndrome patients to radiation carcinogenesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wright, Aaron T.; Magnaldo, Thierry; Sontag, Ryan L.

    Human phenotypes that are highly susceptible to radiation carcinogenesis have been identified. Sensitive phenotypes often display robust regulation of molecular features that modify biological response, which can facilitate identification of relevant pathways/networks. Here we interrogate primary dermal fibroblasts isolated from Gorlin syndrome patients (GDFs), who display a pronounced tumorigenic response to radiation, in comparison to normal human dermal fibroblasts (NHDFs). Our approach exploits newly developed thiol-reactive probes with a flexible click chemistry functional group to define changes in protein thiol profiles in live cell studies, which minimizes artifacts associated with cell lysis. We observe qualitative differences in protein thiol profilesmore » by SDS-PAGE analysis when detection by iodoacetamide vs maleimide probe chemistries are compared, and pretreatment of cells with hydrogen peroxide eliminates detection of the majority of SDS-PAGE bands. Redox probes revealed deficient expression of an apparent 55 kDa protein thiol in GDFs from independent donors, compared with NHDFs. Proteomics tentatively identified this protein as aldehyde dehydrogenase 1A1 (ALDH1A1), a key enzyme regulating retinoic acid synthesis, and this deficiency was confirmed by Western blot. Redox probes revealed additional protein thiol differences between GDFs and NHDFs, including radiation responsive annexin family members. Our results indicate a multifactorial basis for the unusual sensitivity of Gorlin syndrome to radiation carcinogenesis, and the pathways identified have plausible implications for radiation health effects.« less

  12. Ultraviolet Radiation: Cellular Antioxidant Response and the Role of Ocular Aldehyde Dehydrogenase Enzymes

    PubMed Central

    Marchitti, Satori A.; Chen, Ying; Thompson, David C.; Vasiliou, Vasilis

    2011-01-01

    Solar ultraviolet radiation (UVR) exposes the human eye to near constant oxidative stress. Evidence suggests that UVR is the most important environmental insult leading to the development of a variety of ophthalmoheliosis disorders. UVR-induced reactive oxygen species are highly reactive with DNA, proteins and cellular membranes, resulting in cellular and tissue damage. Antioxidant defense systems present in ocular tissues function to combat reactive oxygen species and protect the eye from oxidative damage. Important enzymatic antioxidants are the superoxide dismutases, catalase, glutathione peroxidases, glutathione reductase and members of the aldehyde dehydrogenase (ALDH) superfamily. Glutathione, ascorbic and uric acids, α-tocopherol, NADPH and ferritin serve as small molecule, nonenzymatic antioxidants. Ocular tissues have high levels of these antioxidants which are essential for the maintenance of redox homeostasis in the eye and protection against oxidative damage. ALDH1A1 and ALDH3A1, present abundantly in the cornea and lens, have been shown to have unique roles in the defense against UVR and the downstream effects of oxidative stress. This review presents the properties and functions of ocular antioxidants that play critical roles in the cellular response to UVR exposure, including a focused discussion of the unique roles that the ALDH1A1 and ALDH3A1 enzymes have as multi-functional ocular antioxidants. PMID:21670692

  13. Role and structural characterization of plant aldehyde dehydrogenases from family 2 and family 7.

    PubMed

    Končitíková, Radka; Vigouroux, Armelle; Kopečná, Martina; Andree, Tomáš; Bartoš, Jan; Šebela, Marek; Moréra, Solange; Kopečný, David

    2015-05-15

    Aldehyde dehydrogenases (ALDHs) are responsible for oxidation of biogenic aldehyde intermediates as well as for cell detoxification of aldehydes generated during lipid peroxidation. So far, 13 ALDH families have been described in plants. In the present study, we provide a detailed biochemical characterization of plant ALDH2 and ALDH7 families by analysing maize and pea ALDH7 (ZmALDH7 and PsALDH7) and four maize cytosolic ALDH(cALDH)2 isoforms RF2C, RF2D, RF2E and RF2F [the first maize ALDH2 was discovered as a fertility restorer (RF2A)]. We report the crystal structures of ZmALDH7, RF2C and RF2F at high resolution. The ZmALDH7 structure shows that the three conserved residues Glu(120), Arg(300) and Thr(302) in the ALDH7 family are located in the substrate-binding site and are specific to this family. Our kinetic analysis demonstrates that α-aminoadipic semialdehyde, a lysine catabolism intermediate, is the preferred substrate for plant ALDH7. In contrast, aromatic aldehydes including benzaldehyde, anisaldehyde, cinnamaldehyde, coniferaldehyde and sinapaldehyde are the best substrates for cALDH2. In line with these results, the crystal structures of RF2C and RF2F reveal that their substrate-binding sites are similar and are formed by an aromatic cluster mainly composed of phenylalanine residues and several nonpolar residues. Gene expression studies indicate that the RF2C gene, which is strongly expressed in all organs, appears essential, suggesting that the crucial role of the enzyme would certainly be linked to the cell wall formation using aldehydes from phenylpropanoid pathway as substrates. Finally, plant ALDH7 may significantly contribute to osmoprotection because it oxidizes several aminoaldehydes leading to products known as osmolytes.

  14. Aldehyde Oxidase 4 Plays a Critical Role in Delaying Silique Senescence by Catalyzing Aldehyde Detoxification.

    PubMed

    Srivastava, Sudhakar; Brychkova, Galina; Yarmolinsky, Dmitry; Soltabayeva, Aigerim; Samani, Talya; Sagi, Moshe

    2017-04-01

    The Arabidopsis ( Arabidopsis thaliana ) aldehyde oxidases are a multigene family of four oxidases (AAO1-AAO4) that oxidize a variety of aldehydes, among them abscisic aldehyde, which is oxidized to the phytohormone abscisic acid. Toxic aldehydes are generated in plants both under normal conditions and in response to stress. The detoxification of such aldehydes by oxidation is attributed to aldehyde dehydrogenases but never to aldehyde oxidases. The feasibility of the detoxification of aldehydes in siliques via oxidation by AAO4 was demonstrated, first, by its ability to efficiently oxidize an array of aromatic and aliphatic aldehydes, including the reactive carbonyl species (RCS) acrolein, hydroxyl-2-nonenal, and malondialdehyde. Next, exogenous application of several aldehydes to siliques in AAO4 knockout (KO) Arabidopsis plants induced severe tissue damage and enhanced malondialdehyde levels and senescence symptoms, but not in wild-type siliques. Furthermore, abiotic stresses such as dark and ultraviolet C irradiation caused an increase in endogenous RCS and higher expression levels of senescence marker genes, leading to premature senescence of KO siliques, whereas RCS and senescence marker levels in wild-type siliques were hardly affected. Finally, in naturally senesced KO siliques, higher endogenous RCS levels were associated with enhanced senescence molecular markers, chlorophyll degradation, and earlier seed shattering compared with the wild type. The aldehyde-dependent differential generation of superoxide and hydrogen peroxide by AAO4 and the induction of AAO4 expression by hydrogen peroxide shown here suggest a self-amplification mechanism for detoxifying additional reactive aldehydes produced during stress. Taken together, our results indicate that AAO4 plays a critical role in delaying senescence in siliques by catalyzing aldehyde detoxification. © 2017 American Society of Plant Biologists. All Rights Reserved.

  15. Aldehyde dehydrogenase 1 (ALDH1) expression is an independent prognostic factor in triple negative breast cancer (TNBC).

    PubMed

    Ma, Fei; Li, Huihui; Li, Yiqun; Ding, Xiaoyan; Wang, Haijuan; Fan, Ying; Lin, Chen; Qian, Haili; Xu, Binghe

    2017-04-01

    Triple negative breast cancer (TNBC) is a subset of breast cancer that is highly aggressive and has a poor prognosis. Meanwhile, cancer stem cells (CSCs) are also characterized by a strong tumorigenic potential, which might be partly responsible for the aggressive behavior of TNBC. We previously showed that CSCs are enriched in TNBC cell lines and tissues. Further experiments in animal models revealed higher tumorigenicity of CSCs sorted from TNBC cell lines. In this study, we aimed to determine the clinical relationship between CSCs and TNBC by exploring the expression of aldehyde dehydrogenase 1 (ALDH1), which is a putative marker of breast CSCs, in TNBC tissues.ALDH1 levels in paraffin-embedded tumor tissues from 158 TNBC patients were evaluated by immunohistochemistry staining using an ALDH1A1 primary antibody. Staining evaluation was performed independently by two pathologists, and the expression level of ALDH1 was evaluated in terms of the percentage and intensity of positive cells. The association of immunohistochemistry staining of ALDH1 expression with clinical parameters was also analyzed.ALDH1 expression in tumor cells was observed in 88 out of 158 cases (55.7%). Analysis of clinicopathological parameters showed that the immunohistochemistry staining of ALDH1 was significantly correlated with tumor size (P = 0.02) and stage (P = 0.04). Survival analysis in patients with ALDH1 expression demonstrated shorter relapse-free survival (RFS) and overall survival (OS) times (P = 0.01; P = 0.001). Moreover, Cox multivariate analysis revealed that ALDH1 expression was an independent prognostic indicator of RFS and OS (P = 0.04; P = 0.04).Immunohistochemistry staining of ALDH1 in tumor cells is an independent prognostic indicator of RFS and OS in TNBC patients.

  16. Alcohol Dehydrogenase-1B (rs1229984) and Aldehyde Dehydrogenase-2 (rs671) Genotypes Are Strong Determinants of the Serum Triglyceride and Cholesterol Levels of Japanese Alcoholic Men.

    PubMed

    Yokoyama, Akira; Yokoyama, Tetsuji; Matsui, Toshifumi; Mizukami, Takeshi; Kimura, Mitsuru; Matsushita, Sachio; Higuchi, Susumu; Maruyama, Katsuya

    2015-01-01

    Elevated serum triglyceride (TG) and high-density-lipoprotein cholesterol (HDL-C) levels are common in drinkers. The fast-metabolizing alcohol dehydrogenase-1B encoded by the ADH1B*2 allele (vs. ADH1B*1/*1 genotype) and inactive aldehyde dehydrogenase-2 encoded by the ALDH2*2 allele (vs. ALDH2*1/*1 genotype) modify ethanol metabolism and are prevalent (≈90% and ≈40%, respectively) in East Asians. We attempted to evaluate the associations between the ADH1B and ALDH2 genotypes and lipid levels in alcoholics. The population consisted of 1806 Japanese alcoholic men (≥40 years) who had undergone ADH1B and ALDH2 genotyping and whose serum TG, total cholesterol, and HDL-C levels in the fasting state had been measured within 3 days after admission. High serum levels of TG (≥150 mg/dl), HDL-C (>80 mg/dl), and low-density-lipoprotein cholesterol (LDL-C calculated by the Friedewald formula ≥140 mg/dl) were observed in 24.3%, 16.8%, and 15.6%, respectively, of the subjects. Diabetes, cirrhosis, smoking, and body mass index (BMI) affected the serum lipid levels. Multivariate analysis revealed that the presence of the ADH1B*2 allele and the active ALDH2*1/*1 genotype increased the odds ratio (OR; 95% confidence interval) for a high TG level (2.22 [1.67-2.94] and 1.39 [0.99-1.96], respectively), and decreased the OR for a high HDL-C level (0.37 [0.28-0.49] and 0.51 [0.37-0.69], respectively). The presence of the ADH1B*2 allele decreased the OR for a high LDL-C level (0.60 [0.45-0.80]). The ADH1B*2 plus ALDH2*1/*1 combination yielded the highest ORs for high TG levels and lowest OR for a high HDL-C level. The genotype effects were more prominent in relation to the higher levels of TG (≥220 mg/dl) and HDL-C (≥100 mg/dl). The fast-metabolizing ADH1B and active ALDH2, and especially a combination of the two were strongly associated with higher serum TG levels and lower serum HDL-C levels of alcoholics. The fast-metabolizing ADH1B was associated with lower serum LDL

  17. Effect of pentachlorophenol and 2,6-dichloro-4-nitrophenol on the activity of cDNA-expressed human alcohol and aldehyde dehydrogenases.

    PubMed

    Kollock, Ronny; Rost, Katharina; Batke, Monika; Glatt, Hansruedi

    2009-12-15

    Pentachlorophenol (PCP) and 2,6-dichloro-4-nitrophenol (DCNP), potent inhibitors of phenol sulphotransferases, are frequently used in animal studies to elucidate the role of these enzymes in the biotransformation and toxicity of xenobiotics. An unexpected finding with 1-hydroxymethylpyrene--a strong decrease in the excretion of the corresponding carboxylic acid in rats concurrently treated with PCP-led us to suspect that this sulphotransferase inhibitor may also affect alcohol dehydrogenases (ADHs) and/or aldehyde dehydrogenases (ALDHs). Subsequently we investigated the influence of PCP and DCNP on the activity of cDNA-expressed human ADHs and ALDHs. PCP inhibited all four ADHs studied. The inhibition was strong for ADH3 (K(i) 1.4 microM, K(i)' 5.2 microM, mixed-type) and ADH2 (K(i) 3.7 microM, competitive), but moderate for ADH4 (K(i) 81 microM, competitive) and ADH1C (K(i)' 310 microM, uncompetitive). Activities of ALDH2 and ALDH3A1 were unaffected by PCP (used up to a concentration of 1 mM). In contrast, DCNP primarily inhibited ALDH2 (K(i)=K(i)' 7.4 microM, non-competitive), showed moderate competitive inhibition of ADH2 (K(i) 160 microM) and ADH4 (K(i) 710 microM), but did not affect the remaining enzymes (ADH1C, ADH3 and ALDH3A1). The study demonstrates that caution is required when using putative specific enzyme inhibitors in biotransformation studies.

  18. RP-HPLC-fluorescence analysis of aliphatic aldehydes: application to aldehyde-generating enzymes HACL1 and SGPL1

    PubMed Central

    Mezzar, Serena; de Schryver, Evelyn; Van Veldhoven, Paul P.

    2014-01-01

    Long-chain aldehydes are commonly produced in various processes, such as peroxisomal α-oxidation of long-chain 3-methyl-branched and 2-hydroxy fatty acids and microsomal breakdown of phosphorylated sphingoid bases. The enzymes involved in the aldehyde-generating steps of these processes are 2-hydroxyacyl-CoA lyase (HACL1) and sphingosine-1-phosphate lyase (SGPL1), respectively. In the present work, nonradioactive assays for these enzymes were developed employing the Hantzsch reaction. Tridecanal (C13-al) and heptadecanal (C17-al) were selected as model compounds and cyclohexane-1,3-dione as 1,3-diketone, and the fluorescent derivatives were analyzed by reversed phase (RP)-HPLC. Assay mixture composition, as well as pH and heating, were optimized for C13-al and C17-al. Under optimized conditions, these aldehydes could be quantified in picomolar range and different long-chain aldehyde derivatives were well resolved with a linear gradient elution by RP-HPLC. Aldehydes generated by recombinant enzymes could easily be detected via this method. Moreover, the assay allowed to document activity or deficiency in tissue homogenates and fibroblast lysates without an extraction step. In conclusion, a simple, quick, and cheap assay for the study of HACL1 and SGPL1 activities was developed, without relying on expensive mass spectrometric detectors or radioactive substrates. PMID:24323699

  19. Body odor aldehyde reduction by acetic acid bacterial extract including enzymes: alcohol dehydrogenase and aldehyde dehydrogenase.

    PubMed

    Yoshioka, N; Kurata, K; Takahashi, T; Ariizumi, M; Mori, T; Fujisawa, H; Kameyama, N; Okuyama, Y

    2018-06-13

    Body odor is mainly caused by secreted sweat. Although sweat is almost odorless immediately after secretion, decomposition or denaturation of components contained in sweat by bacteria on the skin surface contributes to unpleasant body odor. Body odor is due to various substances and aldehydes are primarily detected in body odor [1-4]. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  20. Alcohol and aldehyde dehydrogenase gene polymorphisms and oropharyngolaryngeal, esophageal and stomach cancers in Japanese alcoholics.

    PubMed

    Yokoyama, A; Muramatsu, T; Omori, T; Yokoyama, T; Matsushita, S; Higuchi, S; Maruyama, K; Ishii, H

    2001-03-01

    Alcohol dehydrogenase-2 (ADH2) and aldehyde dehydrogenase-2 (ALDH2) gene polymorphisms play roles in ethanol metabolism, drinking behavior and esophageal carcinogenesis in Japanese; however, the combined influence of ADH2 and ALDH2 genotypes on other aerodigestive tract cancers have not been investigated. ADH2/ALDH2 genotyping was performed on lymphocyte DNA samples from Japanese alcoholic men (526 cancer-free; 159 with solitary or multiple aerodigestive tract cancers, including 33 oropharyngolaryngeal, 112 esophageal, 38 stomach and 22 multiple primary cancers in two or three organs). After adjustment for age, drinking and smoking habits, and ADH2/ALDH2 genotypes, the presence of either ADH2*1/2*1 or ALDH2*1/2*2 significantly increased the risk for oropharyngolaryngeal cancer [odds ratios (ORs), 6.68 with ADH2*1/2*1 and 18.52 with ALDH2*1/2*2] and esophageal cancer (ORs, 2.64 and 13.50, respectively). For patients with both ADH2*1/2*1 and ALDH2*1/2*2, the risks for oropharyngolaryngeal and esophageal cancers were enhanced in a multiplicative fashion (OR = 121.77 and 40.40, respectively). A positive association with ALDH2*1/2*2 alone was observed for stomach cancer patients who also had oropharyngolaryngeal and/or esophageal cancer (OR = 110.58), but it was not observed for those with stomach cancer alone. Furthermore, in the presence of ALDH2*1/2*2, the risks for multiple intra-esophageal cancers (OR = 3.43) and for esophageal cancer with oropharyngolaryngeal and/or stomach cancer (OR = 3.95) were higher than the risks for solitary intra-esophageal cancer and for esophageal cancer alone, but these tendencies were not observed for ADH2*1/2*1 genotype. Alcoholics' population attributable risks due to ADH2/ALDH2 polymorphisms were estimated to be 82.0% for oropharyngolaryngeal cancer and 63.9% for esophageal cancer.

  1. Polymorphisms of alcohol dehydrogenase-1B and aldehyde dehydrogenase-2 and the blood and salivary ethanol and acetaldehyde concentrations of Japanese alcoholic men.

    PubMed

    Yokoyama, Akira; Tsutsumi, Eri; Imazeki, Hiromi; Suwa, Yoshihide; Nakamura, Chizu; Yokoyama, Tetsuji

    2010-07-01

    The effects of genetic polymorphism of aldehyde dehydrogenase-2 (ALDH2) on alcohol metabolism are striking in nonalcoholics, and the effects of genetic polymorphism of alcohol dehydrogenase-1B (ADH1B) are modest at most, whereas genetic polymorphisms of both strongly affect the susceptibility to alcoholism and upper aerodigestive tract (UADT) cancer of drinkers. We evaluated associations between ADH1B/ADH1C/ALDH2 genotypes and the blood and salivary ethanol and acetaldehyde levels of 168 Japanese alcoholic men who came to our hospital for the first time in the morning and had been drinking until the day before. The ethanol levels in their blood and saliva were similar, but the acetaldehyde levels in their saliva were much higher than in their blood, probably because of acetaldehyde production by oral bacteria. Blood and salivary ethanol and acetaldehyde levels were both significantly higher in the subjects with the less active ADH1B*1/*1 genotype than in the ADH1B*2 carriers, but none of the levels differed according to ALDH2 genotype. Significant linkage disequilibrium was detected between the ADH1B and ADH1C genotypes, but ADH1C genotype did not affect the blood or salivary ethanol or acetaldehyde levels. High blood acetaldehyde levels were found even in the active ALDH2*1/*1 alcoholics, which were comparable with the levels of the inactive heterozygous ALDH2*1/*2 alcoholics with less active ADH1B*1/*1. The slope of the increase in blood acetaldehyde level as the blood ethanol level increased was significantly steeper in alcoholics with inactive heterozygous ALDH2*1/*2 plus ADH1B*2 allele than with any other genotype combinations, but the slopes of the increase in salivary acetaldehyde level as the salivary ethanol level increased did not differ between the groups of subjects with any combinations of ALDH2 and ADH1B genotypes. The ADH1B/ALDH2 genotype affected the blood and salivary ethanol and acetaldehyde levels of nonabstinent alcoholics in a different manner

  2. Aldehyde dehydrogenase 2 polymorphism for development to hepatocellular carcinoma in East Asian alcoholic liver cirrhosis.

    PubMed

    Abe, Hiroshi; Aida, Yuta; Seki, Nobuyoshi; Sugita, Tomonori; Tomita, Yoichi; Nagano, Tomohisa; Itagaki, Munenori; Sutoh, Satoshi; Nagatsuma, Keisuke; Itoh, Kyoko; Matsuura, Tomokazu; Aizawa, Yoshio

    2015-09-01

    We aimed to clarify the influences of aldehyde dehydrogenase 2 (ALDH2), alcohol dehydrogenase 1B (ADH1B) polymorphisms, and ethanol consumption profile to hepatocellular carcinoma (HCC) development in alcoholic liver cirrhosis without chronic hepatitis B and C virus infection (non-B non-C). Of 236 freshly diagnosed non-B non-C alcoholic liver cirrhosis patients, 67 were diagnosed as HCC and the remaining 169 as not having HCC. The relationship between the genetic polymorphisms and development to HCC were evaluated in well-matched patients with HCC (HCC group, n = 67) and without HCC (non-HCC group, n = 67) using propensity scores in age, sex, and prevalence of diabetes mellitus. Daily amount of ethanol consumption was significantly lower (P = 0.005), and consumptive period was significantly longer (P = 0.003) in HCC group than non-HCC group. Of 134 well-matched patients, 113 (84.3%) had ALDH2*1/*1 genotype and 21 (15.7%) had ALDH2*1/*2 genotype. In HCC development, consumptive long period (P = 0.007) and carrying ALDH2*1/*2 genotype (P = 0.026) were identified as significant factors independently participated, while there was no relation to ADH1B polymorphism. In addition, consumptive period was significantly longer in HCC group than non-HCC group in ALDH2*1/*1 genotype patients (P = 0.0005), while there was no difference in profile of ethanol consumption in ALDH2*1/*2 genotype patients. Among HCC group, daily (P = 3.78 × 10(-6) ) and cumulative amount (P = 4.89 × 10(-6) ) of ethanol consumption were significantly higher in ALDH2*1/*1 genotype patients than ALDH2*1/*2 genotype patients. In alcoholic liver cirrhosis, investigations of ALDH2 polymorphism and ethanol consumption profile are useful for prediction of HCC development. © 2015 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

  3. YLL056C from Saccharomyces cerevisiae encodes a novel protein with aldehyde reductase activity.

    PubMed

    Wang, Han-Yu; Xiao, Di-Fan; Zhou, Chang; Wang, Lin-Lu; Wu, Lan; Lu, Ya-Ting; Xiang, Quan-Ju; Zhao, Ke; Li, Xi; Ma, Meng -Gen

    2017-06-01

    The short-chain dehydrogenase/reductase (SDR) family, the largest family in dehydrogenase/reductase superfamily, is divided into "classical," "extended," "intermediate," "divergent," "complex," and "atypical" groups. Recently, several open reading frames (ORFs) were characterized as intermediate SDR aldehyde reductase genes in Saccharomyces cerevisiae. However, no functional protein in the atypical group has been characterized in S. cerevisiae till now. Herein, we report that an uncharacterized ORF YLL056C from S. cerevisiae was significantly upregulated under high furfural (2-furaldehyde) or 5-(hydroxymethyl)-2-furaldehyde concentrations, and transcription factors Yap1p, Hsf1p, Pdr1/3p, Yrr1p, and Stb5p likely controlled its upregulated transcription. This ORF indeed encoded a protein (Yll056cp), which was grouped into the atypical subgroup 7 in the SDR family and localized to the cytoplasm. Enzyme activity assays showed that Yll056cp is not a quinone or ketone reductase but an NADH-dependent aldehyde reductase, which can reduce at least seven aldehyde compounds. This enzyme showed the best Vmax, Kcat, and Kcat/Km to glycolaldehyde, but the highest affinity (Km) to formaldehyde. The optimum pH and temperature of this enzyme was pH 6.5 for reduction of glycolaldehyde, furfural, formaldehyde, butyraldehyde, and propylaldehyde, and 30 °C for reduction of formaldehyde or 35 °C for reduction of glycolaldehyde, furfural, butyraldehyde, and propylaldehyde. Temperature and pH affected stability of this enzyme and this influence varied with aldehyde substrate. Metal ions, salts, and chemical protective additives, especially at high concentrations, had different influence on enzyme activities for reduction of different aldehydes. This research provided guidelines for study of more uncharacterized atypical SDR enzymes from S. cerevisiae and other organisms.

  4. Acute and chronic ethanol exposure differentially alters alcohol dehydrogenase and aldehyde dehydrogenase activity in the zebrafish liver.

    PubMed

    Tran, Steven; Nowicki, Magda; Chatterjee, Diptendu; Gerlai, Robert

    2015-01-02

    Chronic ethanol exposure paradigms have been successfully used in the past to induce behavioral and central nervous system related changes in zebrafish. However, it is currently unknown whether chronic ethanol exposure alters ethanol metabolism in adult zebrafish. In the current study we examine the effect of acute ethanol exposure on adult zebrafish behavioral responses, as well as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activity in the liver. We then examine how two different chronic ethanol exposure paradigms (continuous and repeated ethanol exposure) alter behavioral responses and liver enzyme activity during a subsequent acute ethanol challenge. Acute ethanol exposure increased locomotor activity in a dose-dependent manner. ADH activity was shown to exhibit an inverted U-shaped curve and ALDH activity was decreased by ethanol exposure at all doses. During the acute ethanol challenge, animals that were continuously housed in ethanol exhibited a significantly reduced locomotor response and increased ADH activity, however, ALDH activity did not change. Zebrafish that were repeatedly exposed to ethanol demonstrated a small but significant attenuation of the locomotor response during the acute ethanol challenge but ADH and ALDH activity was similar to controls. Overall, we identified two different chronic ethanol exposure paradigms that differentially alter behavioral and physiological responses in zebrafish. We speculate that these two paradigms may allow dissociation of central nervous system-related and liver enzyme-dependent ethanol induced changes in zebrafish. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Evaluation of aldehyde dehydrogenase 1 and transcription factors in both primary breast cancer and axillary lymph node metastases as a prognostic factor.

    PubMed

    Ito, Maiko; Shien, Tadahiko; Omori, Masako; Mizoo, Taeko; Iwamoto, Takayuki; Nogami, Tomohiro; Motoki, Takayuki; Taira, Naruto; Doihara, Hiroyoshi; Miyoshi, Shinichiro

    2016-05-01

    Aldehyde dehydrogenase 1 (ALDH1) is a marker of breast cancer stem cells, and the expression of ALDH1 may be a prognostic factor of poor clinical outcome. The epithelial-mesenchymal transition may produce cells with stem-cell-like properties promoted by transcription factors. We investigated the expression of ALDH1 and transcription factors in both primary and metastatic lesions, and prognostic value of them in breast cancer patients with axillary lymph node metastasis (ALNM). Forty-seven breast cancer patients with ALNM who underwent surgery at Okayama University Hospital from 2002 to 2008 were enrolled. We retrospectively evaluated the levels of ALDH1 and transcription factors, such as Snail, Slug and Twist, in both primary and metastatic lesions by immunohistochemistry. In primary lesions, the positive rate of ALDH1, Snail, Slug and Twist was 19, 49, 40 and 26%, respectively. In lymph nodes, that of ALDH1, Snail, Slug and Twist was 21, 32, 13 and 23%, respectively. The expression of ALDH1 or transcription factors alone was not significantly associated with a poor prognosis. However, co-expression of ALDH1 and Slug in primary lesions was associated with a shorter DFS (P = 0.009). The evaluation of the co-expression of ALDH1 and transcription factors in primary lesions may be useful in prognosis of node-positive breast cancers.

  6. Arabidopsis aldehyde dehydrogenase 10 family members confer salt tolerance through putrescine-derived 4-aminobutyrate (GABA) production.

    PubMed

    Zarei, Adel; Trobacher, Christopher P; Shelp, Barry J

    2016-10-11

    Polyamines represent a potential source of 4-aminobutyrate (GABA) in plants exposed to abiotic stress. Terminal catabolism of putrescine in Arabidopsis thaliana involves amine oxidase and the production of 4-aminobutanal, which is a substrate for NAD + -dependent aminoaldehyde dehydrogenase (AMADH). Here, two AMADH homologs were chosen (AtALDH10A8 and AtALDH10A9) as candidates for encoding 4-aminobutanal dehydrogenase activity for GABA synthesis. The two genes were cloned and soluble recombinant proteins were produced in Escherichia coli. The pH optima for activity and catalytic efficiency of recombinant AtALDH10A8 with 3-aminopropanal as substrate was 10.5 and 8.5, respectively, whereas the optima for AtALDH10A9 were approximately 9.5. Maximal activity and catalytic efficiency were obtained with NAD + and 3-aminopropanal, followed by 4-aminobutanal; negligible activity was obtained with betaine aldehyde. NAD + reduction was accompanied by the production of GABA and β-alanine, respectively, with 4-aminobutanal and 3-aminopropanal as substrates. Transient co-expression systems using Arabidopsis cell suspension protoplasts or onion epidermal cells and several organelle markers revealed that AtALDH10A9 was peroxisomal, but AtALDH10A8 was cytosolic, although the N-terminal 140 amino acid sequence of AtALDH10A8 localized to the plastid. Root growth of single loss-of-function mutants was more sensitive to salinity than wild-type plants, and this was accompanied by reduced GABA accumulation.

  7. Hydrogen Sulfide Ameliorates Homocysteine-Induced Cognitive Dysfunction by Inhibition of Reactive Aldehydes Involving Upregulation of ALDH2.

    PubMed

    Li, Min; Zhang, Ping; Wei, Hai-Jun; Li, Man-Hong; Zou, Wei; Li, Xiang; Gu, Hong-Feng; Tang, Xiao-Qing

    2017-04-01

    Homocysteine, a risk factor for Alzheimer's disease, induces cognitive dysfunction. Reactive aldehydes play an important role in cognitive dysfunction. Aldehyde-dehydrogenase 2 detoxifies reactive aldehydes. Hydrogen sulfide, a novel neuromodulator, has neuroprotective effects and regulates learning and memory. Our previous work confirmed that the disturbance of hydrogen sulfide synthesis is invovled in homocysteine-induced defects in learning and memory. Therefore, the present work was to explore whether hydrogen sulfide ameliorates homocysteine-generated cognitive dysfunction and to investigate whether its underlying mechanism is related to attenuating accumulation of reactive aldehydes by upregulation of aldehyde-dehydrogenase 2. The cognitive function of rats was assessed by the Morris water maze test and the novel object recognition test. The levels of malondialdehyde, 4-hydroxynonenal, and glutathione as well as the activity of aldehyde-dehydrogenase 2 were determined by enzyme linked immunosorbent assay; the expression of aldehyde-dehydrogenase 2 was detected by western blot. The behavior experiments, Morris water maze test and novel objects recognition test, showed that homocysteine induced deficiency in learning and memory in rats, and this deficiency was reversed by treatment of NaHS (a donor of hydrogen sulfide). We demonstrated that NaHS inhibited homocysteine-induced increases in generations of MDA and 4-HNE in the hippocampus of rats and that hydrogen sulfide reversed homocysteine-induced decreases in the level of glutathione as well as the activity and expression of aldehyde-dehydrogenase 2 in the hippocampus of rats. Hydrogen sulfide ameliorates homocysteine-induced impairment in cognitive function by decreasing accumulation of reactive aldehydes as a result of upregulations of glutathione and aldehyde-dehydrogenase 2. © The Author 2016. Published by Oxford University Press on behalf of CINP.

  8. Hydrogen Sulfide Ameliorates Homocysteine-Induced Cognitive Dysfunction by Inhibition of Reactive Aldehydes Involving Upregulation of ALDH2

    PubMed Central

    Li, Min; Zhang, Ping; Wei, Hai-jun; Li, Man-Hong; Li, Xiang; Gu, Hong-Feng

    2017-01-01

    Abstract Background: Homocysteine, a risk factor for Alzheimer’s disease, induces cognitive dysfunction. Reactive aldehydes play an important role in cognitive dysfunction. Aldehyde-dehydrogenase 2 detoxifies reactive aldehydes. Hydrogen sulfide, a novel neuromodulator, has neuroprotective effects and regulates learning and memory. Our previous work confirmed that the disturbance of hydrogen sulfide synthesis is invovled in homocysteine-induced defects in learning and memory. Therefore, the present work was to explore whether hydrogen sulfide ameliorates homocysteine-generated cognitive dysfunction and to investigate whether its underlying mechanism is related to attenuating accumulation of reactive aldehydes by upregulation of aldehyde-dehydrogenase 2. Methods: The cognitive function of rats was assessed by the Morris water maze test and the novel object recognition test. The levels of malondialdehyde, 4-hydroxynonenal, and glutathione as well as the activity of aldehyde-dehydrogenase 2 were determined by enzyme linked immunosorbent assay; the expression of aldehyde-dehydrogenase 2 was detected by western blot. Results: The behavior experiments, Morris water maze test and novel objects recognition test, showed that homocysteine induced deficiency in learning and memory in rats, and this deficiency was reversed by treatment of NaHS (a donor of hydrogen sulfide). We demonstrated that NaHS inhibited homocysteine-induced increases in generations of MDA and 4-HNE in the hippocampus of rats and that hydrogen sulfide reversed homocysteine-induced decreases in the level of glutathione as well as the activity and expression of aldehyde-dehydrogenase 2 in the hippocampus of rats. Conclusion: Hydrogen sulfide ameliorates homocysteine-induced impairment in cognitive function by decreasing accumulation of reactive aldehydes as a result of upregulations of glutathione and aldehyde-dehydrogenase 2. PMID:27988490

  9. cDNA cloning and analysis of betaine aldehyde dehydrogenase, a salt inducible enzyme in sugar beet

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McCue, K.F.; Hanson, A.D.

    1990-05-01

    Betaine accumulates and serves as a compatible osmolyte in some plants subjected to drought or salinity stress. The last enzyme in the betaine biosynthetic pathway is betaine aldehyde dehydrogenase (BADH). The activity of BADH increases in response to increasing salinity levels. This increase in activity corresponds to an increase in protein detectable by immunoblotting, and to an increase in the translatable BADH mRNA. BADH was cloned from a cDNA library constructed in {lambda}gt10 using poly(A){sup +} RNA from sugar beets salinized to 500 mM NaCl. cDNAs were size selected (>1kb) before ligation into the vector, and the library was screenedmore » with a spinach BADH cDNA probe. Three nearly full length clones obtained were confirmed as BADH by their nucleotide and deduced amino acid homology to spinach BADH. Clones averaged 1.8 kb and contained open reading frames of 500 amino acids at 80% identity with spinach BADH. RNA gel blot analysis of poly(A){sup +} RNA indicated that salinization to 500 mM NaCl resulted in a 5-fold increase of BADH mRNA level.« less

  10. Genetic polymorphisms of alcohol dehydrogenase-1B and aldehyde dehydrogenase-2 and liver cirrhosis, chronic calcific pancreatitis, diabetes mellitus, and hypertension among Japanese alcoholic men.

    PubMed

    Yokoyama, Akira; Mizukami, Takeshi; Matsui, Toshifumi; Yokoyama, Tetsuji; Kimura, Mitsuru; Matsushita, Sachio; Higuchi, Susumu; Maruyama, Katsuya

    2013-08-01

    The presence of the less-active form of alcohol dehydrogenase-1B encoded by ADH1B*1/*1 (vs. *2 allele) and active form of aldehyde dehydrogenase-2 (ALDH2) encoded by ALDH2*1/*1 (vs. *2 allele) increases the risk of alcoholism in East Asians. The subjects in this cross-sectional survey were 1,902 Japanese alcoholic men (≥40 years) who underwent ADH1B/ALDH2 genotyping. Age-adjusted daily alcohol consumption did not differ according to the ADH1B/ALDH2 genotypes. The age-adjusted odds ratios (AORs; 95% confidence interval) for liver cirrhosis (LC; n = 359, 1.58 [1.19 to 2.09]), chronic calcific pancreatitis (CP; n = 80, 2.24 [1.20 to 4.20]), and diabetes mellitus (DM; n = 383, 1.51 [1.15 to 1.99]) were higher in the ADH1B*2 allele carriers than in the ADH1B*1/*1 carriers. The AORs for LC (1.43 [1.01 to 2.02]), CP (1.68 [0.80 to 3.53]), DM (1.63 [1.15 to 2.30]), and hypertension (HT; n = 495, 1.52 [1.11 to 2.07]) were higher in the ALDH2*1/*1 carriers than in the ALDH2*1/*2 carriers. The ADH1B*2-associated AOR for LC was 2.08 (1.46 to 2.94) among those aged 40 to 59 years, but 0.89 (0.56 to 1.43) among those aged 60 years or over, and the interaction between ADH1B genotype and age on the LC risk was significant (p = 0.009). When the group with non-LC and no/mild fibrosis was used as controls, the ADH1B*2-associated AORs increased according to the severity of their liver disease: 1.67 (1.32 to 2.11) for the group with non-LC and serum type IV collagen values ≥200 ng/ml, 1.81 (1.24 to 2.63) for the group of Child-Pugh class A LC, and 3.17 (1.98 to 5.07) for the group with Child-Pugh class B/C LC. Anti-hepatitis C virus (HCV) antibody was positive in 103 patients, and the groups with a high anti-HCV antibody titer and either the ADH1B*2/*2 genotype or the ALDH2*1/*1 genotype had the highest AORs (8.83 and 4.90, respectively). The population attributable fraction (PAF) due to the ADH1B*2 allele was 29% for LC, 47% for CP, and 27% for DM, and the PAF due to the ALDH2*1/*1

  11. Alcohol and aldehyde dehydrogenase gene polymorphisms influence susceptibility to esophageal cancer in Japanese alcoholics.

    PubMed

    Yokoyama, A; Muramatsu, T; Omori, T; Matsushita, S; Yoshimizu, H; Higuchi, S; Yokoyama, T; Maruyama, K; Ishii, H

    1999-11-01

    Studies have consistently demonstrated that inactive aldehyde dehydrogenase-2 (ALDH2), encoded by ALDH2*1/2*2, is closely associated with alcohol-related carcinogenesis. Recently, the contributions of alcohol dehydrogenase-2 (ADH2) polymorphism to alcoholism, esophageal cancer, and the flushing response have also been described. To determine the effects of ALDH2 and ADH2 genotypes in genetically based cancer susceptibility, lymphocyte DNA samples from 668 Japanese alcoholic men more than 40 years of age (91 with and 577 without esophageal cancer) were genotyped and the results were expressed as odds ratios (ORs). This study also tested 82 of the alcoholics with esophageal cancer to determine whether cancer susceptibility is associated with patients' responses to simple questions about current or former flushing after drinking a glass of beer. The frequencies of ADH2*1/2*1 and ALDH2*1/2*2 were significantly higher in alcoholics with, than in those without, esophageal cancer (0.473 vs. 0.289 and 0.560 vs. 0.099, respectively). After adjustment for drinking and smoking, the analysis showed significantly increased cancer risk for alcoholics with either ADH2*1/2*I (OR = 2.03) or ALDH2*1/2*2 (OR = 12.76). For those having ADH2*1/2*1 combined with ALDH2*1/2*2, the esophageal cancer risk was enhanced in a multiplicative fashion (OR = 27.66). Responses to flushing questions showed that only 47.8% of the ALDH2*1/2*2 heterozygotes with ADH2*1/ 2*1, compared with 92.3% of those with ALDH2*1/2*2 and the ADH2*2 allele, reported current or former flushing. Genotyping showed that for alcoholics who reported ever flushing, the questionnaire was 71.4% correct in identifying ALDH2*1/2*2 and 87.9% correct in identifying ALDH2*1/2*1. Japanese alcoholics can be divided into cancer susceptibility groups on the basis of their combined ADH2 and ALDH2 genotypes. The flushing questionnaire can predict high risk ALDH2*1/2*2 fairly accurately in persons with ADH2*2 allele, but a reliable

  12. Genetic polymorphisms of alcohol dehydrogense-1B and aldehyde dehydrogenase-2, alcohol flushing, mean corpuscular volume, and aerodigestive tract neoplasia in Japanese drinkers.

    PubMed

    Yokoyama, Akira; Mizukami, Takeshi; Yokoyama, Tetsuji

    2015-01-01

    Genetic polymorphisms of alcohol dehydrogenase-1B (ADH1B) and aldehyde dehydrogenase-2 (ALDH2) modulate exposure levels to ethanol/acetaldehyde. Endoscopic screening of 6,014 Japanese alcoholics yielded high detection rates of esophageal squamous cell carcinoma (SCC; 4.1%) and head and neck SCC (1.0%). The risks of upper aerodigestive tract SCC/dysplasia, especially of multiple SCC/dysplasia, were increased in a multiplicative fashion by the presence of a combination of slow-metabolizing ADH1B*1/*1 and inactive heterozygous ALDH2*1/*2 because of prolonged exposure to higher concentrations of ethanol/acetaldehyde. A questionnaire asking about current and past facial flushing after drinking a glass (≈180 mL) of beer is a reliable tool for detecting the presence of inactive ALDH2. We invented a health-risk appraisal (HRA) model including the flushing questionnaire and drinking, smoking, and dietary habits. Esophageal SCC was detected at a high rate by endoscopic mass-screening in high HRA score persons. A total of 5.0% of 4,879 alcoholics had a history of (4.0%) or newly diagnosed (1.0%) gastric cancer. Their high frequency of a history of gastric cancer is partly explained by gastrectomy being a risk factor for alcoholism because of altered ethanol metabolism, e.g., by blood ethanol level overshooting. The combination of H. pylori-associated atrophic gastritis and ALDH2*1/*2 showed the greatest risk of gastric cancer in alcoholics. High detection rates of advanced colorectal adenoma/carcinoma were found in alcoholics, 15.7% of 744 immunochemical fecal occult blood test (IFOBT)-negative alcoholics and 31.5% of the 393 IFOBT-positive alcoholics. Macrocytosis with an MCV≥106 fl increased the risk of neoplasia in the entire aerodigestive tract of alcoholics, suggesting that poor nutrition as well as ethanol/acetaldehyde exposure plays an important role in neoplasia.

  13. A spontaneously immortalized Schwann cell line from aldose reductase-deficient mice as a useful tool for studying polyol pathway and aldehyde metabolism.

    PubMed

    Niimi, Naoko; Yako, Hideji; Takaku, Shizuka; Kato, Hiroshi; Matsumoto, Takafumi; Nishito, Yasumasa; Watabe, Kazuhiko; Ogasawara, Saori; Mizukami, Hiroki; Yagihashi, Soroku; Chung, Sookja K; Sango, Kazunori

    2018-03-01

    The increased glucose flux into the polyol pathway via aldose reductase (AR) is recognized as a major contributing factor for the pathogenesis of diabetic neuropathy, whereas little is known about the functional significance of AR in the peripheral nervous system. Spontaneously immortalized Schwann cell lines established from long-term cultures of AR-deficient and normal C57BL/6 mouse dorsal root ganglia and peripheral nerves can be useful tools for studying the physiological and pathological roles of AR. These cell lines, designated as immortalized knockout AR Schwann cells 1 (IKARS1) and 1970C3, respectively, demonstrated distinctive Schwann cell phenotypes, such as spindle-shaped morphology and immunoreactivity to S100, p75 neurotrophin receptor, and vimentin, and extracellular release of neurotrophic factors. Conditioned media obtained from these cells promoted neuronal survival and neurite outgrowth of cultured adult mouse dorsal root ganglia neurons. Microarray and real-time RT-PCR analyses revealed significantly down-regulated mRNA expression of polyol pathway-related enzymes, sorbitol dehydrogenase and ketohexokinase, in IKARS1 cells compared with those in 1970C3 cells. In contrast, significantly up-regulated mRNA expression of aldo-keto reductases (AKR1B7 and AKR1B8) and aldehyde dehydrogenases (ALDH1L2, ALDH5A1, and ALDH7A1) was detected in IKARS1 cells compared with 1970C3 cells. Exposure to reactive aldehydes (3-deoxyglucosone, methylglyoxal, and 4-hydroxynonenal) significantly up-regulated the mRNA expression of AKR1B7 and AKR1B8 in IKARS1 cells, but not in 1970C3 cells. Because no significant differences in viability between these two cell lines after exposure to these aldehydes were observed, it can be assumed that the aldehyde detoxification is taken over by AKR1B7 and AKR1B8 in the absence of AR. © 2017 International Society for Neurochemistry.

  14. Cardiac-specific overexpression of aldehyde dehydrogenase 2 exacerbates cardiac remodeling in response to pressure overload.

    PubMed

    Dassanayaka, Sujith; Zheng, Yuting; Gibb, Andrew A; Cummins, Timothy D; McNally, Lindsey A; Brittian, Kenneth R; Jagatheesan, Ganapathy; Audam, Timothy N; Long, Bethany W; Brainard, Robert E; Jones, Steven P; Hill, Bradford G

    2018-06-01

    Pathological cardiac remodeling during heart failure is associated with higher levels of lipid peroxidation products and lower abundance of several aldehyde detoxification enzymes, including aldehyde dehydrogenase 2 (ALDH2). An emerging idea that could explain these findings concerns the role of electrophilic species in redox signaling, which may be important for adaptive responses to stress or injury. The purpose of this study was to determine whether genetically increasing ALDH2 activity affects pressure overload-induced cardiac dysfunction. Mice subjected to transverse aortic constriction (TAC) for 12 weeks developed myocardial hypertrophy and cardiac dysfunction, which were associated with diminished ALDH2 expression and activity. Cardiac-specific expression of the human ALDH2 gene in mice augmented myocardial ALDH2 activity but did not improve cardiac function in response to pressure overload. After 12 weeks of TAC, ALDH2 transgenic mice had larger hearts than their wild-type littermates and lower capillary density. These findings show that overexpression of ALDH2 augments the hypertrophic response to pressure overload and imply that downregulation of ALDH2 may be an adaptive response to certain forms of cardiac pathology. Copyright © 2018. Published by Elsevier B.V.

  15. Aldehyde dehydrogenase induction in arsenic-exposed rat bladder epithelium.

    PubMed

    Huang, Ya-Chun; Yu, Hsin-Su; Chai, Chee-Yin

    2016-01-01

    Arsenic is widely distributed in the environment. Many human cancers, including urothelial carcinoma (UC), show a dose-dependent relationship with arsenic exposure in the south-west coast of Taiwan (also known as the blackfoot disease (BFD) areas). However, the molecular mechanisms of arsenic-mediated UC carcinogenesis has not yet been defined. In vivo study, the rat bladder epithelium were exposed with arsenic for 48 h. The proteins were extracted from untreated and arsenic-treated rat bladder cells and utilized two-dimensional gel electrophoresis and mass spectrometry. Selected peptides were extracted from the gel and identified by quadrupole-time of flight (Q-TOF) Ultima-Micromass spectra. The significantly difference expression of proteins in arsenic-treated groups as compared with untreated groups was confirmed by immunohistochemistry (IHC) and western blotting. We found that thirteen proteins were down-regulated and nine proteins were up-regulated in arsenic-treated rat bladder cells when compared with untreated groups. The IHC and western blotting results confirmed that aldehyde dehydrogenase (ALDH) protein was up-regulated in arsenic-treated rat bladder epithelium. Expression of ALDH protein was significantly higher in UC patients from BFD areas than those from non-BFD areas using IHC (p=0.018). In conclusion, the ALDH protein expression could be used as molecular markers for arsenic-induced transformation. Copyright © 2015 Elsevier GmbH. All rights reserved.

  16. Mutations in ALDH1A3 represent a frequent cause of microphthalmia/anophthalmia in consanguineous families.

    PubMed

    Abouzeid, Hana; Favez, Tatiana; Schmid, Angélique; Agosti, Céline; Youssef, Mohammed; Marzouk, Iman; El Shakankiry, Nihal; Bayoumi, Nader; Munier, Francis L; Schorderet, Daniel F

    2014-08-01

    Anophthalmia or microphthalmia (A/M), characterized by absent or small eye, can be unilateral or bilateral and represent developmental anomalies due to the mutations in several genes. Recently, mutations in aldehyde dehydrogenase family 1, member A3 (ALDH1A3) also known as retinaldehyde dehydrogenase 3, have been reported to cause A/M. Here, we screened a cohort of 75 patients with A/M and showed that mutations in ALDH1A3 occurred in six families. Based on this series, we estimate that mutations in ALDH1A3 represent a major cause of A/M in consanguineous families, and may be responsible for approximately 10% of the cases. Screening of this gene should be performed in a first line of investigation, together with SOX2. © 2014 WILEY PERIODICALS, INC.

  17. Inhibition of human alcohol and aldehyde dehydrogenases by aspirin and salicylate: assessment of the effects on first-pass metabolism of ethanol.

    PubMed

    Lee, Shou-Lun; Lee, Yung-Pin; Wu, Min-Li; Chi, Yu-Chou; Liu, Chiu-Ming; Lai, Ching-Long; Yin, Shih-Jiun

    2015-05-01

    Previous studies have reported that aspirin significantly reduced the first-pass metabolism (FPM) of ethanol in humans thereby increasing adverse effects of alcohol. The underlying causes, however, remain poorly understood. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), principal enzymes responsible for metabolism of ethanol, are complex enzyme families that exhibit functional polymorphisms among ethnic groups and distinct tissue distributions. We investigated the inhibition profiles by aspirin and its major metabolite salicylate of ethanol oxidation by recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and acetaldehyde oxidation by ALDH1A1 and ALDH2, at pH 7.5 and 0.5 mM NAD(+). Competitive inhibition pattern was found to be a predominant type among the ADHs and ALDHs studied, although noncompetitive and uncompetitive inhibitions were also detected in a few cases. The inhibition constants of salicylate for the ADHs and ALDHs were considerably lower than that of aspirin with the exception of ADH1A that can be ascribed to a substitution of Ala-93 at the bottom of substrate pocket as revealed by molecular docking experiments. Kinetic inhibition equation-based simulations show at higher therapeutic levels of blood plasma salicylate (1.5 mM) that the decrease of activities at 2-10 mM ethanol for ADH1A/ADH2 and ADH1B2/ADH1B3 are predicted to be 75-86% and 31-52%, respectively, and that the activity decline for ALDH1A1 and ALDH2 at 10-50 μM acetaldehyde to be 62-73%. Our findings suggest that salicylate may substantially inhibit hepatic FPM of alcohol at both the ADH and ALDH steps when concurrent intaking aspirin. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Cloning, functional expression and characterization of a bifunctional 3-hydroxybutanal dehydrogenase /reductase involved in acetone metabolism by Desulfococcus biacutus.

    PubMed

    Frey, Jasmin; Rusche, Hendrik; Schink, Bernhard; Schleheck, David

    2016-11-25

    The strictly anaerobic, sulfate-reducing bacterium Desulfococcus biacutus can utilize acetone as sole carbon and energy source for growth. Whereas in aerobic and nitrate-reducing bacteria acetone is activated by carboxylation with CO 2 to acetoacetate, D. biacutus involves CO as a cosubstrate for acetone activation through a different, so far unknown pathway. Proteomic studies indicated that, among others, a predicted medium-chain dehydrogenase/reductase (MDR) superfamily, zinc-dependent alcohol dehydrogenase (locus tag DebiaDRAFT_04514) is specifically and highly produced during growth with acetone. The MDR gene DebiaDRAFT_04514 was cloned and overexpressed in E. coli. The purified recombinant protein required zinc as cofactor, and accepted NADH/NAD + but not NADPH/NADP + as electron donor/acceptor. The pH optimum was at pH 8, and the temperature optimum at 45 °C. Highest specific activities were observed for reduction of C 3 - C 5 -aldehydes with NADH, such as propanal to propanol (380 ± 15 mU mg -1 protein), butanal to butanol (300 ± 24 mU mg -1 ), and 3-hydroxybutanal to 1,3-butanediol (248 ± 60 mU mg -1 ), however, the enzyme also oxidized 3-hydroxybutanal with NAD + to acetoacetaldehyde (83 ± 18 mU mg -1 ). The enzyme might play a key role in acetone degradation by D. biacutus, for example as a bifunctional 3-hydroxybutanal dehydrogenase/reductase. Its recombinant production may represent an important step in the elucidation of the complete degradation pathway.

  19. Activation of human liver 3 alpha-hydroxysteroid dehydrogenase by sulphobromophthalein.

    PubMed Central

    Matsuura, K; Tamada, Y; Deyashiki, Y; Miyabe, Y; Nakanishi, M; Ohya, I; Hara, A

    1996-01-01

    Human liver contains at least two isoenzymes (DD2 and DD4) of 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase. The NADP(H)-linked oxidoreductase activities of DD4 were activated more than 4-fold by sulphobromophthalein at concentrations above 20 microM and under physiological pH conditions. Sulphobromophthalein did not stimulate the activities of DD2 and human liver aldehyde reductase, which are functionally and/or structurally related to DD4. No stimulatory effect on the activity of DD4 was observed with other organic anions such as Indocyanine Green, haematin and Rose Bengal. The binding of sulphobromophthalein to DD4 was instantaneous and reversible, and was detected by fluorescence and ultrafiltration assays. The activation by sulphobromophthalein decreased the activation energy in the dehydrogenation reaction for the enzyme, and increased both kcat, and Km values for the coenzymes and substrates. Kinetic analyses with respect to concentrations of NADP+ and (S)-(+)-indan-1-ol indicated that sulphobromophthalein was a non-essential activator of mixed type showing a dissociation constant of 2.6 microM. Thus, the human 3 alpha-hydroxysteroid dehydrogenase isoenzyme has a binding site specific to sulphobromophthalein, and the hepatic metabolism mediated by this isoenzyme may be influenced when this drug is administered. PMID:8546681

  20. Cloning of a cDNA encoding rat aldehyde dehydrogenase with high activity for retinal oxidation.

    PubMed

    Bhat, P V; Labrecque, J; Boutin, J M; Lacroix, A; Yoshida, A

    1995-12-12

    Retinoic acid (RA), an important regulator of cell differentiation, is biosynthesized from retinol via retinal by a two-step oxidation process. We previously reported the purification and partial amino acid (aa) sequence of a rat kidney aldehyde dehydrogenase (ALDH) isozyme that catalyzed the oxidation of 9-cis and all-trans retinal to corresponding RA with high efficiency [Labrecque et al. Biochem. J. 305 (1995) 681-684]. A rat kidney cDNA library was screened using a 291-bp PCR product generated from total kidney RNA using a pair of oligodeoxyribonucleotide primers matched with the aa sequence. The full-length rat kidney ALDH cDNA contains a 2315-bp (501 aa) open reading frame (ORF). The aa sequence of rat kidney ALDH is 89, 96 and 87% identical to that of the rat cytosolic ALDH, the mouse cytosolic ALDH and human cytosolic ALDH, respectively. Northern blot and RT-PCR-mediated analysis demonstrated that rat kidney ALDH is strongly expressed in kidney, lung, testis, intestine, stomach and trachea, but weakly in the liver.

  1. Cloning and molecular evolution of the aldehyde dehydrogenase 2 gene (Aldh2) in bats (Chiroptera).

    PubMed

    Chen, Yao; Shen, Bin; Zhang, Junpeng; Jones, Gareth; He, Guimei

    2013-02-01

    Old World fruit bats (Pteropodidae) and New World fruit bats (Phyllostomidae) ingest significant quantities of ethanol while foraging. Mitochondrial aldehyde dehydrogenase (ALDH2, encoded by the Aldh2 gene) plays an important role in ethanol metabolism. To test whether the Aldh2 gene has undergone adaptive evolution in frugivorous and nectarivorous bats in relation to ethanol elimination, we sequenced part of the coding region of the gene (1,143 bp, ~73 % coverage) in 14 bat species, including three Old World fruit bats and two New World fruit bats. Our results showed that the Aldh2 coding sequences are highly conserved across all bat species we examined, and no evidence of positive selection was detected in the ancestral branches leading to Old World fruit bats and New World fruit bats. Further research is needed to determine whether other genes involved in ethanol metabolism have been the targets of positive selection in frugivorous and nectarivorous bats.

  2. Human class II (pi) alcohol dehydrogenase has a redox-specific function in norepinephrine metabolism.

    PubMed Central

    Mårdh, G; Dingley, A L; Auld, D S; Vallee, B L

    1986-01-01

    Studies of the function of human alcohol dehydrogenase (ADH) have revealed substrates that are virtually unique for class II ADH (pi ADH). It catalyzes the formation of the intermediary glycols of norepinephrine metabolism, 3,4-dihydroxyphenylglycol and 4-hydroxy-3-methoxyphenylglycol, from the corresponding aldehydes 3,4-dihydroxymandelaldehyde and 4-hydroxy-3-methoxymandelaldehyde with Km values of 55 and 120 microM and kcat/Km ratios of 14,000 and 17,000 mM-1 X min-1; these are from 60- to 210-fold higher than those obtained with class I ADH isozymes. The catalytic preference of class II ADH also extends to benzaldehydes. The kcat/Km values for the reduction of benzaldehyde, 3,4-dihydroxybenzaldehyde and 4-hydroxy-3-methoxybenzaldehyde by pi ADH are from 9- to 29-fold higher than those for a class I isozyme, beta 1 gamma 2 ADH. Furthermore, the norepinephrine aldehydes are potent inhibitors of alcohol (ethanol) oxidation by pi ADH. The high catalytic activity of pi ADH-catalyzed reduction of the aldehydes in combination with a possible regulatory function of the aldehydes in the oxidative direction leads to essentially "unidirectional" catalysis by pi ADH. These features and the presence of pi ADH in human liver imply a physiological role for pi ADH in the degradation of circulating epinephrine and norepinephrine. PMID:3466164

  3. Characteristics and expression patterns of the aldehyde dehydrogenase (ALDH) gene superfamily of foxtail millet (Setaria italica L.).

    PubMed

    Chen, Zhu; Chen, Ming; Xu, Zhao-shi; Li, Lian-cheng; Chen, Xue-ping; Ma, You-zhi

    2014-01-01

    Recent genomic sequencing of the foxtail millet, an abiotic, stress-tolerant crop, has provided a great opportunity for novel gene discovery and functional analysis of this popularly-grown grass. However, few stress-mediated gene families have been studied. Aldehyde dehydrogenases (ALDHs) comprise a gene superfamily encoding NAD (P) +-dependent enzymes that play the role of "aldehyde scavengers", which indirectly detoxify cellular ROS and reduce the effect of lipid peroxidation meditated cellular toxicity under various environmental stresses. In the current paper, we identified a total of 20 ALDH genes in the foxtail millet genome using a homology search and a phylogenetic analysis and grouped them into ten distinct families based on their amino acid sequence identity. Furthermore, evolutionary analysis of foxtail millet reveals that both tandem and segmental duplication contributed significantly to the expansion of its ALDH genes. The exon-intron structures of members of the same family in foxtail millet or the orthologous genes in rice display highly diverse distributions of their exonic and intronic regions. Also, synteny analysis shows that the majority of foxtail millet and rice ALDH gene homologs exist in the syntenic blocks between the two, implying that these ALDH genes arose before the divergence of cereals. Semi-quantitative and real-time quantitative PCR data reveals that a few SiALDH genes are expressed in an organ-specific manner and that the expression of a number of foxtail millet ALDH genes, such as, SiALDH7B1, SiALDH12A1 and SiALDH18B2 are up-regulated by osmotic stress, cold, H2O2, and phytohormone abscisic acid (ABA). Furthermore, the transformation of SiALDH2B2, SiALDH10A2, SiALDH5F1, SiALDH22A1, and SiALDH3E2 into Escherichia coli (E.coli) was able to improve their salt tolerance. Taken together, our results show that genome-wide identification characteristics and expression analyses provide unique opportunities for assessing the functional

  4. 13-cis-retinoic acid competitively inhibits 3 alpha-hydroxysteroid oxidation by retinol dehydrogenase RoDH-4: a mechanism for its anti-androgenic effects in sebaceous glands?

    PubMed

    Karlsson, Teresa; Vahlquist, Anders; Kedishvili, Natalia; Törmä, Hans

    2003-03-28

    Retinol dehydrogenase-4 (RoDH-4) converts retinol and 13-cis-retinol to corresponding aldehydes in human liver and skin in the presence of NAD(+). RoDH-4 also converts 3 alpha-androstanediol and androsterone into dihydrotestosterone and androstanedione, which may stimulate sebum secretion. This oxidative 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) activity of RoDH-4 is competitively inhibited by retinol and 13-cis-retinol. Here, we further examine the substrate specificity of RoDH-4 and the inhibition of its 3 alpha-HSD activity by retinoids. Recombinant RoDH-4 oxidized 3,4-didehydroretinol-a major form of vitamin A in the skin-to its corresponding aldehyde. 13-cis-retinoic acid (isotretinoin), 3,4-didehydroretinoic acid, and 3,4-didehydroretinol, but not all-trans-retinoic acid or the synthetic retinoids acitretin and adapalene, were potent competitive inhibitors of the oxidative 3 alpha-HSD activity of RoDH-4, i.e., reduced the formation of dihydrotestosterone and androstandione in vitro. Extrapolated to the in vivo situation, this effect might explain the unique sebosuppressive effect of isotretinoin when treating acne.

  5. Autoantibody against aldehyde dehydrogenase 2 could be a biomarker to monitor progression of Graves' orbitopathy.

    PubMed

    Cheng, Kai-Chun; Wu, Yu-Jen; Cheng, Kai-Hung; Cheng, Kai-Yuan; Chen, Kuo-Jen; Wu, Wen-Chuan; Lee, Po-Yen; Chang, Cheng-Hsien

    2018-06-01

    This study surveyed the novel autoantigens expressed in the orbital fat tissue of patients with Graves' orbitopathy (GO) and explored the possibility of the autoantibodies against novel autoantigens as biomarkers for GO. We used immuno-proteomic methods to survey novel autoantigens expressed in the orbit fat tissue of GO patients and confirmed by enzyme-linked immunosorbent assay (ELISA). One protein spot (aldehyde dehydrogenase 2 (ALDH2)) revealed high reactivity with the GO serum than did the healthy control serum and was further verified by ELISA. We found that the plasma anti-ALDH2 antibody level was increased in GO patients compared to healthy control donors. In addition, anti-ALDH2 antibody level was correlated with GO activity classified by clinical activity score(r = 0.588, p < 0.001, using Pearson's correlation). These increased levels of anti-ALDH2 antibody in GO serum suggested that ALDH2 could attribute target autoantigen in GO, and anti-ALDH2 autoantibody might serve as a biomarker for GO and help to predict disease activity.

  6. Characterization of an allylic/benzyl alcohol dehydrogenase from Yokenella sp. strain WZY002, an organism potentially useful for the synthesis of α,β-unsaturated alcohols from allylic aldehydes and ketones.

    PubMed

    Ying, Xiangxian; Wang, Yifang; Xiong, Bin; Wu, Tingting; Xie, Liping; Yu, Meilan; Wang, Zhao

    2014-04-01

    A novel whole-cell biocatalyst with high allylic alcohol-oxidizing activities was screened and identified as Yokenella sp. WZY002, which chemoselectively reduced the C=O bond of allylic aldehydes/ketones to the corresponding α,β-unsaturated alcohols at 30°C and pH 8.0. The strain also had the capacity of stereoselectively reducing aromatic ketones to (S)-enantioselective alcohols. The enzyme responsible for the predominant allylic/benzyl alcohol dehydrogenase activity was purified to homogeneity and designated YsADH (alcohol dehydrogenase from Yokenella sp.), which had a calculated subunit molecular mass of 36,411 Da. The gene encoding YsADH was subsequently expressed in Escherichia coli, and the purified recombinant YsADH protein was characterized. The enzyme strictly required NADP(H) as a coenzyme and was putatively zinc dependent. The optimal pH and temperature for crotonaldehyde reduction were pH 6.5 and 65°C, whereas those for crotyl alcohol oxidation were pH 8.0 and 55°C. The enzyme showed moderate thermostability, with a half-life of 6.2 h at 55°C. It was robust in the presence of organic solvents and retained 87.5% of the initial activity after 24 h of incubation with 20% (vol/vol) dimethyl sulfoxide. The enzyme preferentially catalyzed allylic/benzyl aldehydes as the substrate in the reduction of aldehydes/ketones and yielded the highest activity of 427 U mg(-1) for benzaldehyde reduction, while the alcohol oxidation reaction demonstrated the maximum activity of 79.9 U mg(-1) using crotyl alcohol as the substrate. Moreover, kinetic parameters of the enzyme showed lower Km values and higher catalytic efficiency for crotonaldehyde/benzaldehyde and NADPH than for crotyl alcohol/benzyl alcohol and NADP(+), suggesting the nature of being an aldehyde reductase.

  7. Characterization of an Allylic/Benzyl Alcohol Dehydrogenase from Yokenella sp. Strain WZY002, an Organism Potentially Useful for the Synthesis of α,β-Unsaturated Alcohols from Allylic Aldehydes and Ketones

    PubMed Central

    Ying, Xiangxian; Wang, Yifang; Xiong, Bin; Wu, Tingting; Xie, Liping; Yu, Meilan

    2014-01-01

    A novel whole-cell biocatalyst with high allylic alcohol-oxidizing activities was screened and identified as Yokenella sp. WZY002, which chemoselectively reduced the C=O bond of allylic aldehydes/ketones to the corresponding α,β-unsaturated alcohols at 30°C and pH 8.0. The strain also had the capacity of stereoselectively reducing aromatic ketones to (S)-enantioselective alcohols. The enzyme responsible for the predominant allylic/benzyl alcohol dehydrogenase activity was purified to homogeneity and designated YsADH (alcohol dehydrogenase from Yokenella sp.), which had a calculated subunit molecular mass of 36,411 Da. The gene encoding YsADH was subsequently expressed in Escherichia coli, and the purified recombinant YsADH protein was characterized. The enzyme strictly required NADP(H) as a coenzyme and was putatively zinc dependent. The optimal pH and temperature for crotonaldehyde reduction were pH 6.5 and 65°C, whereas those for crotyl alcohol oxidation were pH 8.0 and 55°C. The enzyme showed moderate thermostability, with a half-life of 6.2 h at 55°C. It was robust in the presence of organic solvents and retained 87.5% of the initial activity after 24 h of incubation with 20% (vol/vol) dimethyl sulfoxide. The enzyme preferentially catalyzed allylic/benzyl aldehydes as the substrate in the reduction of aldehydes/ketones and yielded the highest activity of 427 U mg−1 for benzaldehyde reduction, while the alcohol oxidation reaction demonstrated the maximum activity of 79.9 U mg−1 using crotyl alcohol as the substrate. Moreover, kinetic parameters of the enzyme showed lower Km values and higher catalytic efficiency for crotonaldehyde/benzaldehyde and NADPH than for crotyl alcohol/benzyl alcohol and NADP+, suggesting the nature of being an aldehyde reductase. PMID:24509923

  8. Choline dehydrogenase interacts with SQSTM1/p62 to recruit LC3 and stimulate mitophagy.

    PubMed

    Park, Sungwoo; Choi, Seon-Guk; Yoo, Seung-Min; Son, Jin H; Jung, Yong-Keun

    2014-01-01

    CHDH (choline dehydrogenase) is an enzyme catalyzing the dehydrogenation of choline to betaine aldehyde in mitochondria. Apart from this well-known activity, we report here a pivotal role of CHDH in mitophagy. Knockdown of CHDH expression impairs CCCP-induced mitophagy and PARK2/parkin-mediated clearance of mitochondria in mammalian cells, including HeLa cells and SN4741 dopaminergic neuronal cells. Conversely, overexpression of CHDH accelerates PARK2-mediated mitophagy. CHDH is found on both the outer and inner membranes of mitochondria in resting cells. Interestingly, upon induction of mitophagy, CHDH accumulates on the outer membrane in a mitochondrial potential-dependent manner. We found that CHDH is not a substrate of PARK2 but interacts with SQSTM1 independently of PARK2 to recruit SQSTM1 into depolarized mitochondria. The FB1 domain of CHDH is exposed to the cytosol and is required for the interaction with SQSTM1, and overexpression of the FB1 domain only in cytosol reduces CCCP-induced mitochondrial degradation via competitive interaction with SQSTM1. In addition, CHDH, but not the CHDH FB1 deletion mutant, forms a ternary protein complex with SQSTM1 and MAP1LC3 (LC3), leading to loading of LC3 onto the damaged mitochondria via SQSTM1. Further, CHDH is crucial to the mitophagy induced by MPP+ in SN4741 cells. Overall, our results suggest that CHDH is required for PARK2-mediated mitophagy for the recruitment of SQSTM1 and LC3 onto the mitochondria for cargo recognition.

  9. Sensory irritation structure-activity study of inhaled aldehydes in B6C3F1 and Swiss-Webster mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Steinhagen, W.H.; Barrow, C.S.

    1984-03-15

    The sensory irritation potential of a series of saturated and unsaturated aliphatic and cyclic aldehydes was investigated in B6C3F1 and Swiss-Webster mice. With the reflex decrease in respiratory rate as the endpoint response, alpha, beta-unsaturated aliphatic aldehydes yielded RD/sub 50/ values (concentration which elicits a 50% decrease in respiratory rate) ranging from 1 to 5 ppm while saturated aliphatic aldehydes with two or more carbons produced RD/sub 50/ values from 750 to 4200 ppm. Cyclic aldehydes produced intermediate RD/sub 50/ values which ranged from 60 to 400 ppm. No statistically significant differences were found between concentration-response curves of B6C3F1 andmore » Swiss-Webster mice. Saturated aliphatic aldehydes with two or more carbons were nearly 1000 times less potent than formaldehyde. Although the mechanisms responsible for stimulation of trigeminal nerve endings by airborne chemicals are poorly understood, several hypotheses may help to explain the differences seen in this study. For example, the sensory irritation potency of the saturated aliphatic aldehydes diminished with their reported dehydration constants which may determine the degree to which these aldehydes crosslink with receptor proteins. The sensory irritation potency of acrolein and crotonaldehyde was probably due to 1,2 or 1,4 addition reactions. Additionally, molecular conformation and a recently published physical mechanism may contribute to sensory irritation responses, particularly for the less reactive aldehydes. Tentative threshold limit values (TLVs), based upon prevention of sensory irritation, were extrapolated from the RD/sub 50/ values of Swiss-Webster mice. With the exception of crotonaldehyde, good agreement was found with currently published TLVs.« less

  10. Association between aldehyde dehydrogenase 2 polymorphisms and the incidence of diabetic retinopathy among Japanese subjects with type 2 diabetes mellitus.

    PubMed

    Morita, Kazunori; Saruwatari, Junji; Miyagawa, Haruna; Uchiyashiki, Yoshihiro; Oniki, Kentaro; Sakata, Misaki; Kajiwara, Ayami; Yoshida, Akira; Jinnouchi, Hideaki; Nakagawa, Kazuko

    2013-09-13

    Mitochondrial aldehyde dehydrogenase 2 (ALDH2) detoxifies reactive aldehydes in the micro- and macrovasculature. These substrates, including methylglyoxal and 4-hydroxynonenal formed from glucose and lipids, cause protein carbonylation and mitochondrial dysfunction, forming advanced glycation end products (AGEs). The present study aimed to confirm the association between the inactive ALDH2*2 allele and diabetic retinopathy (DR). A retrospective longitudinal analysis was conducted, among 234 Japanese patients with type 2 diabetes mellitus (DM) (156 males and 78 females) who had no DR signs at baseline and were treated for more than half a year. The ALDH2*1/*2 alleles were determined using a real-time TaqMan allelic discrimination assay. Multivariate-adjusted hazard ratios (HRs) and 95% confidential intervals (CIs) for the cumulative incidence of the development of DR were examined using a Cox proportional hazard model, taking drinking habits and the serum γ-glutamyltransferase (GGT) level into consideration. The frequency of the ALDH2*2 allele was 22.3%. Fifty-two subjects cumulatively developed DR during the follow-up period of 5.5 ± 2.5 years. The ALDH2*2 allele carriers had a significantly higher incidence of DR than the non-carriers (HR: 1.92; P = 0.02). The incidence of DR was significantly higher in the drinkers with the ALDH2*2 allele than in those with the ALDH2*1/*1 genotype (HR: 2.61; P = 0.03), while the incidence of DR in the non-drinkers did not differ significantly between the ALDH2 genotype groups (P > 0.05). The incidence of DR was significantly higher in the ALDH2*2 allele carriers with a high GGT level than in the non-carriers with a high or low GGT level (HR: 2.45; P = 0.03; and HR: 2.63; P = 0.03, respectively). To the best of our knowledge, this is the first report of a significant association between the ALDH2*2 allele and the incidence of DR. These findings provide additional evidence that ALDH2 protects both microvasculature and

  11. Genetic polymorphisms of alcohol and aldehyde dehydrogenases and glutathione S-transferase M1 and drinking, smoking, and diet in Japanese men with esophageal squamous cell carcinoma.

    PubMed

    Yokoyama, Akira; Kato, Hoichi; Yokoyama, Tetsuji; Tsujinaka, Toshimasa; Muto, Manabu; Omori, Tai; Haneda, Tatsumasa; Kumagai, Yoshiya; Igaki, Hiroyasu; Yokoyama, Masako; Watanabe, Hiroshi; Fukuda, Haruhiko; Yoshimizu, Haruko

    2002-11-01

    The genetic polymorphisms of aldehyde dehydrogenase-2 (ALDH2), alcohol dehydrogenase-2 (ADH2), ADH3, and glutathione S-transferase M1 (GSTM1) influence the metabolism of alcohol and other carcinogens. The ALDH2*1/2*2 genotype, which encodes inactive ALDH2, and ADH2*1/2*1, which encodes the low-activity form of ADH2, enhance the risk for esophageal cancer in East Asian alcoholics. This case-control study of whether the enzyme-related vulnerability for esophageal cancer can be extended to a general population involved 234 Japanese men with esophageal squamous cell carcinoma and 634 cancer-free Japanese men who received annual health checkups. The GSTM1 genotype was not associated with the risk for this cancer. Light drinkers (1-8.9 units/week) with ALDH2*1/2*2 had an esophageal cancer risk 5.82 times that of light drinkers with ALDH2*1/2*1 (reference category), and their risk was similar to that of moderate drinkers (9-17.9 units/week) with ALDH2*1/2*1 (odds ratio = 5.58). The risk for moderate drinkers with ALDH2*1/2*2 (OR = 55.84) exceeded that for heavy drinkers (18+ units/week) with ALDH2*1/2*1 (OR = 10.38). Similar increased risks were observed for those with ADH2*1/2*1. A multiple logistic model including ALDH2, ADH2, and ADH3 genotypes showed that the ADH3 genotype does not significantly affect the risk for esophageal cancer. For individuals with both ALDH2*1/2*2 and ADH2*1/2*1, the risk of esophageal cancer was enhanced in a multiplicative fashion (OR = 30.12), whereas for those with either ALDH2*1/2*2 or ADH2*1/2*1 alone the ORs were 7.36 and 4.11. In comparison with the estimated population-attributable risks for preference for strong alcoholic beverages (30.7%), smoking (53.6%) and for lower intake of green and yellow vegetables (25.7%) and fruit (37.6%), an extraordinarily high proportion of the excessive risk for esophageal cancer in the Japanese males can be attributed to drinking (90.9%), particularly drinking by persons with inactive heterozygous ALDH

  12. The importance of alcohol dehydrogenase in regulation of ethanol metabolism in rat liver cells.

    PubMed Central

    Page, R A; Kitson, K E; Hardman, M J

    1991-01-01

    We used titration with the inhibitors tetramethylene sulphoxide and isobutyramide to assess quantitatively the importance of alcohol dehydrogenase in regulation of ethanol oxidation in rat hepatocytes. In hepatocytes isolated from starved rats the apparent Flux Control Coefficient (calculated assuming a single-substrate irreversible reaction with non-competitive inhibition) of alcohol dehydrogenase is 0.3-0.5. Adjustment of this coefficient to allow for alcohol dehydrogenase being a two-substrate reversible enzyme increases the value by 1.3-1.4-fold. The final value of the Flux Control Coefficient of 0.5-0.7 indicates that alcohol dehydrogenase is a major rate-determining enzyme, but that other factors also have a regulatory role. In hepatocytes from fed rats the Flux Control Coefficient for alcohol dehydrogenase decreases with increasing acetaldehyde concentration. This suggests that, as acetaldehyde concentrations rise, control of the pathway shifts from alcohol dehydrogenase to other enzymes, particularly aldehyde dehydrogenase. There is not a single rate-determining step for the ethanol metabolism pathway and control is shared among several steps. PMID:1898355

  13. Aldehyde dehydrogenase-2 inhibition blocks remote preconditioning in experimental and human models.

    PubMed

    Contractor, Hussain; Støttrup, Nicolaj B; Cunnington, Colin; Manlhiot, Cedric; Diesch, Jonathan; Ormerod, Julian O M; Jensen, Rebekka; Bøtker, Hans Erik; Redington, Andrew; Schmidt, Michael R; Ashrafian, Houman; Kharbanda, Rajesh K

    2013-05-01

    Mitochondrial aldehyde dehydrogenase-2 (ALDH-2) is involved in preconditioning pathways, but its role in remote ischaemic preconditioning (rIPC) is unknown. We investigated its role in animal and human models of rIPC. (i) In a rabbit model of myocardial infarction, rIPC alone reduced infarct size [69 ± 5.8 % (n = 11) to 40 ± 6.5 % (n = 12), P = 0.019]. However, rIPC protection was lost after pre-treatment with the ALDH-2 inhibitor cyanamide (62 ± 7.6 % controls, n = 10, versus 61 ± 6.9 % rIPC after cyanamide, n = 10, P > 0.05). (ii) In a forearm plethysmography model of endothelial ischaemia-reperfusion injury, 24 individuals of Asian ethnic origin underwent combined rIPC and ischaemia-reperfusion (IR). 11 had wild-type (WT) enzyme and 13 carried the Glu504Lys (ALDH2*2) polymorphism (rendering ALDH-2 functionally inactive). In WT individuals, rIPC protected against impairment of response to acetylcholine (P = 0.9), but rIPC failed to protect carriers of Glu504Lys polymorphism (P = 0.004). (iii) In a second model of endothelial IR injury, 12 individuals participated in a double-blind placebo-controlled crossover study, receiving the ALDH-2 inhibitor disulfiram 600 mg od or placebo for 48 h prior to assessment of flow-mediated dilation (FMD) before and after combined rIPC and IR. With placebo, rIPC was effective with no difference in FMD before and after IR (6.18 ± 1.03 % and 4.76 ± 0.93 % P = 0.1), but disulfiram inhibited rIPC with a reduction in FMD after IR (7.87 ± 1.27 % and 3.05 ± 0.53 %, P = 0.001). This study demonstrates that ALDH-2 is involved in the rIPC pathway in three distinct rabbit and human models. This has potential implications for future clinical studies of remote conditioning.

  14. Inhibition of human alcohol and aldehyde dehydrogenases by acetaminophen: Assessment of the effects on first-pass metabolism of ethanol.

    PubMed

    Lee, Yung-Pin; Liao, Jian-Tong; Cheng, Ya-Wen; Wu, Ting-Lun; Lee, Shou-Lun; Liu, Jong-Kang; Yin, Shih-Jiun

    2013-11-01

    Acetaminophen is one of the most widely used over-the-counter analgesic, antipyretic medications. Use of acetaminophen and alcohol are commonly associated. Previous studies showed that acetaminophen might affect bioavailability of ethanol by inhibiting gastric alcohol dehydrogenase (ADH). However, potential inhibitions by acetaminophen of first-pass metabolism (FPM) of ethanol, catalyzed by the human ADH family and by relevant aldehyde dehydrogenase (ALDH) isozymes, remain undefined. ADH and ALDH both exhibit racially distinct allozymes and tissue-specific distribution of isozymes, and are principal enzymes responsible for ethanol metabolism in humans. In this study, we investigated acetaminophen inhibition of ethanol oxidation with recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and inhibition of acetaldehyde oxidation with recombinant human ALDH1A1 and ALDH2. The investigations were done at near physiological pH 7.5 and with a cytoplasmic coenzyme concentration of 0.5 mM NAD(+). Acetaminophen acted as a noncompetitive inhibitor for ADH enzymes, with the slope inhibition constants (Kis) ranging from 0.90 mM (ADH2) to 20 mM (ADH1A), and the intercept inhibition constants (Kii) ranging from 1.4 mM (ADH1C allozymes) to 19 mM (ADH1A). Acetaminophen exhibited noncompetitive inhibition for ALDH2 (Kis = 3.0 mM and Kii = 2.2 mM), but competitive inhibition for ALDH1A1 (Kis = 0.96 mM). The metabolic interactions between acetaminophen and ethanol/acetaldehyde were assessed by computer simulation using inhibition equations and the determined kinetic constants. At therapeutic to subtoxic plasma levels of acetaminophen (i.e., 0.2-0.5 mM) and physiologically relevant concentrations of ethanol (10 mM) and acetaldehyde (10 μm) in target tissues, acetaminophen could inhibit ADH1C allozymes (12-26%) and ADH2 (14-28%) in the liver and small intestine, ADH4 (15-31%) in the stomach, and ALDH1A1 (16-33%) and ALDH2 (8.3-19%) in all 3 tissues. The

  15. Crystallographic and spectroscopic snapshots reveal a dehydrogenase in action

    DOE PAGES

    Huo, Lu; Davis, Ian; Liu, Fange; ...

    2015-01-07

    Aldehydes are ubiquitous intermediates in metabolic pathways and their innate reactivity can often make them quite unstable. There are several aldehydic intermediates in the metabolic pathway for tryptophan degradation that can decay into neuroactive compounds that have been associated with numerous neurological diseases. An enzyme of this pathway, 2-aminomuconate-6-semialdehyde dehydrogenase, is responsible for ‘disarming’ the final aldehydic intermediate. Here we show the crystal structures of a bacterial analogue enzyme in five catalytically relevant forms: resting state, one binary and two ternary complexes, and a covalent, thioacyl intermediate. We also report the crystal structures of a tetrahedral, thiohemiacetal intermediate, a thioacylmore » intermediate and an NAD +-bound complex from an active site mutant. These covalent intermediates are characterized by single-crystal and solution-state electronic absorption spectroscopy. The crystal structures reveal that the substrate undergoes an E/Z isomerization at the enzyme active site before an sp 3-to-sp 2 transition during enzyme-mediated oxidation.« less

  16. Galectin-9 Produced by Intestinal Epithelial Cells Enhances Aldehyde Dehydrogenase Activity in Dendritic Cells in a PI3K- and p38-Dependent Manner.

    PubMed

    de Kivit, Sander; Kostadinova, Atanaska I; Kerperien, JoAnn; Ayechu Muruzabal, Veronica; Morgan, Mary E; Knippels, Leon M J; Kraneveld, Aletta D; Garssen, Johan; Willemsen, Linette E M

    2017-01-01

    Intestinal epithelial cells (IEC) drive regulatory T cell (Treg) responses by promoting the differentiation of aldehyde dehydrogenase (ALDH)-expressing CD103+ dendritic cells (DC). Apical stimulation of TLR9 by CpG DNA on IEC supports galectin-9 expression by IEC, which is promoted by short-chain galacto-oligosaccharides and long-chain fructo-oligosaccharides (GF). While galectin-9 can induce the maturation of monocyte-derived DC (moDC), the contribution of galectin-9 on the induction of ALDH activity in DC is not known. To this end, DC were stimulated with galectin-9, and ALDH activity and the expression of CD103 were assessed. ALDH activity was increased by moDC exposed to galectin-9, while the expression of CD103 remained unaltered. Galectin-9 secreted by IEC apically exposed to CpG DNA and GF enhanced ALDH activity, but not CD103 expression by moDC, which was abrogated upon galectin-9 neutralization. Similar observations were found in murine GM-CSF-cultured bone marrow-derived DC (BMDC). Using Flt3L-cultured BMDC and ex vivo murine splenic DC, it was observed that galectin-9 only enhanced ALDH activity in the presence of GM-CSF in CD103- cells. The induction of ALDH activity in BMDC was dependent on p38 and PI3K signaling. These data indicate a novel role for galectin-9 in modulating innate immunity by inducing ALDH activity in DC. © 2017 S. Karger AG, Basel.

  17. High Aldehyde Dehydrogenase Activity Identifies a Subset of Human Mesenchymal Stromal Cells with Vascular Regenerative Potential.

    PubMed

    Sherman, Stephen E; Kuljanin, Miljan; Cooper, Tyler T; Putman, David M; Lajoie, Gilles A; Hess, David A

    2017-06-01

    During culture expansion, multipotent mesenchymal stromal cells (MSCs) differentially express aldehyde dehydrogenase (ALDH), an intracellular detoxification enzyme that protects long-lived cells against oxidative stress. Thus, MSC selection based on ALDH-activity may be used to reduce heterogeneity and distinguish MSC subsets with improved regenerative potency. After expansion of human bone marrow-derived MSCs, cell progeny was purified based on low versus high ALDH-activity (ALDH hi ) by fluorescence-activated cell sorting, and each subset was compared for multipotent stromal and provascular regenerative functions. Both ALDH l ° and ALDH hi MSC subsets demonstrated similar expression of stromal cell (>95% CD73 + , CD90 + , CD105 + ) and pericyte (>95% CD146 + ) surface markers and showed multipotent differentiation into bone, cartilage, and adipose cells in vitro. Conditioned media (CDM) generated by ALDH hi MSCs demonstrated a potent proliferative and prosurvival effect on human microvascular endothelial cells (HMVECs) under serum-free conditions and augmented HMVEC tube-forming capacity in growth factor-reduced matrices. After subcutaneous transplantation within directed in vivo angiogenesis assay implants into immunodeficient mice, ALDH hi MSC or CDM produced by ALDH hi MSC significantly augmented murine vascular cell recruitment and perfused vessel infiltration compared with ALDH l ° MSC. Although both subsets demonstrated strikingly similar mRNA expression patterns, quantitative proteomic analyses performed on subset-specific CDM revealed the ALDH hi MSC subset uniquely secreted multiple proangiogenic cytokines (vascular endothelial growth factor beta, platelet derived growth factor alpha, and angiogenin) and actively produced multiple factors with chemoattractant (transforming growth factor-β, C-X-C motif chemokine ligand 1, 2, and 3 (GRO), C-C motif chemokine ligand 5 (RANTES), monocyte chemotactic protein 1 (MCP-1), interleukin [IL]-6, IL-8) and matrix

  18. Cytochromes P450 Catalyze the Reduction of α,β-Unsaturated Aldehydes

    PubMed Central

    Amunom, Immaculate; Dieter, Laura J.; Tamasi, Viola; Cai, Jan; Conklin, Daniel J.; Srivastava, Sanjay; Martin, Martha V.; Guengerich, F. Peter; Prough, Russell A.

    2011-01-01

    The metabolism of α,β-unsaturated aldehydes, e.g. 4-hydroxynonenal, involves oxidation to carboxylic acids, reduction to alcohols, and glutathionylation to eventually form mercapturide conjugates. Recently we demonstrated that P450s can oxidize aldehydes to carboxylic acids, a reaction previously thought to involve aldehyde dehydrogenase. When recombinant cytochrome P450 3A4 was incubated with 4-hydroxynonenal, O2, and NADPH, several products were produced, including 1,4-dihydroxynonene (DHN), 4-hydroxy-2-nonenoic acid (HNA), and an unknown metabolite. Several P450s catalyzed the reduction reaction in the order (human) P450 2B6 ≅ P450 3A4 > P450 1A2 > P450 2J2 > (mouse) P450 2c29. Other P450s did not catalyze the reduction reaction (human P450 2E1 & rabbit P450 2B4). Metabolism by isolated rat hepatocytes showed that HNA formation was inhibited by cyanamide, while DHN formation was not affected. Troleandomycin increased HNA production 1.6-fold while inhibiting DHN formation, suggesting that P450 3A11 is a major enzyme involved in rat hepatic clearance of 4-HNE. A fluorescent assay was developed using 9-anthracenealdehyde to measure both reactions. Feeding mice diet containing t-butylated hydroxyanisole increased the level of both activities with hepatic microsomal fractions, but not proportionally. Miconazole (0.5 mM) was a potent inhibitor of these microsomal reduction reactions, while phenytoin and α-naphthoflavone (both at 0.5 mM) were partial inhibitors, suggesting the role of multiple P450 enzymes. The oxidative metabolism of these aldehydes was inhibited >90% in an Ar or CO atmosphere, while the reductive reactions were not greatly affected. These results suggest that P450s are significant catalysts of reduction of α,β-unsaturated aldehydes in liver. PMID:21766881

  19. Demonstration of 3 alpha(17 beta)-hydroxysteroid dehydrogenase distinct from 3 alpha-hydroxysteroid dehydrogenase in hamster liver.

    PubMed Central

    Ohmura, M; Hara, A; Nakagawa, M; Sawada, H

    1990-01-01

    NAD(+)-linked and NADP(+)-linked 3 alpha-hydroxysteroid dehydrogenases were purified to homogeneity from hamster liver cytosol. The two monomeric enzymes, although having similar molecular masses of 38,000, differed from each other in pI values, activation energy and heat stability. The two proteins also gave different fragmentation patterns by gel electrophoresis after digestion with protease. The NADP(+)-linked enzyme catalysed the oxidoreduction of various 3 alpha-hydroxysteroids, whereas the NAD(+)-linked enzyme oxidized the 3 alpha-hydroxy group of pregnanes and some bile acids, and the 17 beta-hydroxy group of testosterone and androstanes. The thermal stabilities of the 3 alpha- and 17 beta-hydroxysteroid dehydrogenase activities of the NAD(+)-linked enzyme were identical, and the two enzyme activities were inhibited by mixing 17 beta- and 3 alpha-hydroxysteroid substrates, respectively. Medroxyprogesterone acetate, hexoestrol and 3 beta-hydroxysteroids competitively inhibited 3 alpha- and 17 beta-hydroxysteroid dehydrogenase activities of the enzyme. These results show that hamster liver contains a 3 alpha(17 beta)-hydroxysteroid dehydrogenase structurally and functionally distinct from 3 alpha-hydroxysteroid dehydrogenase. Images Fig. 1. Fig. 2. PMID:2317205

  20. Aldehyde Dehydrogenase Gene Superfamily in Populus: Organization and Expression Divergence between Paralogous Gene Pairs.

    PubMed

    Tian, Feng-Xia; Zang, Jian-Lei; Wang, Tan; Xie, Yu-Li; Zhang, Jin; Hu, Jian-Jun

    2015-01-01

    Aldehyde dehydrogenases (ALDHs) constitute a superfamily of NAD(P)+-dependent enzymes that catalyze the irreversible oxidation of a wide range of reactive aldehydes to their corresponding nontoxic carboxylic acids. ALDHs have been studied in many organisms from bacteria to mammals; however, no systematic analyses incorporating genome organization, gene structure, expression profiles, and cis-acting elements have been conducted in the model tree species Populus trichocarpa thus far. In this study, a comprehensive analysis of the Populus ALDH gene superfamily was performed. A total of 26 Populus ALDH genes were found to be distributed across 12 chromosomes. Genomic organization analysis indicated that purifying selection may have played a pivotal role in the retention and maintenance of PtALDH gene families. The exon-intron organizations of PtALDHs were highly conserved within the same family, suggesting that the members of the same family also may have conserved functionalities. Microarray data and qRT-PCR analysis indicated that most PtALDHs had distinct tissue-specific expression patterns. The specificity of cis-acting elements in the promoter regions of the PtALDHs and the divergence of expression patterns between nine paralogous PtALDH gene pairs suggested that gene duplications may have freed the duplicate genes from the functional constraints. The expression levels of some ALDHs were up- or down-regulated by various abiotic stresses, implying that the products of these genes may be involved in the adaptation of Populus to abiotic stresses. Overall, the data obtained from our investigation contribute to a better understanding of the complexity of the Populus ALDH gene superfamily and provide insights into the function and evolution of ALDH gene families in vascular plants.

  1. Pharmacological activation of aldehyde dehydrogenase 2 promotes osteoblast differentiation via bone morphogenetic protein-2 and induces bone anabolic effect

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mittal, Monika; Pal, Subhashis; China, Shyamsundar

    Aldehyde dehydrogenases (ALDHs) are a family of enzymes involved in detoxifying aldehydes. Previously, we reported that an ALDH inhibitor, disulfiram caused bone loss in rats and among ALDHs, osteoblast expressed only ALDH2. Loss-of-function mutation in ALDH2 gene is reported to cause bone loss in humans which suggested its importance in skeletal homeostasis. We thus studied whether activating ALDH2 by N-(1, 3-benzodioxol-5-ylmethyl)-2, 6-dichlorobenzamide (alda-1) had osteogenic effect. We found that alda-1 increased and acetaldehyde decreased the differentiation of rat primary osteoblasts and expressions of ALDH2 and bone morphogenetic protein-2 (BMP-2). Silencing ALDH2 in osteoblasts abolished the alda-1 effects. Further, alda-1 attenuatedmore » the acetaldehyde-induced lipid-peroxidation and oxidative stress. BMP-2 is essential for bone regeneration and alda-1 increased its expression in osteoblasts. We then showed that alda-1 (40 mg/kg dose) augmented bone regeneration at the fracture site with concomitant increase in BMP-2 protein compared with control. The osteogenic dose (40 mg/kg) of alda-1 attained a bone marrow concentration that was stimulatory for osteoblast differentiation, suggesting that the tissue concentration of alda-1 matched its pharmacologic effect. In addition, alda-1 promoted modeling-directed bone growth and peak bone mass achievement, and increased bone mass in adult rats which reiterated its osteogenic effect. In osteopenic ovariectomized (OVX) rats, alda-1 reversed trabecular osteopenia with attendant increase in serum osteogenic marker (procollagen type I N-terminal peptide) and decrease in oxidative stress. Alda-1 has no effect on liver and kidney function. We conclude that activating ALDH2 by alda-1 had an osteoanabolic effect involving increased osteoblastic BMP-2 production and decreased OVX-induced oxidative stress. - Highlights: • Alda-1 induced osteoblast differentiation that involved upregulation of ALDH2 and BMP-2 • Alda

  2. Improved Schmidt Conversion of Aldehydes to Nitriles Using Azidotrimethylsilane in 1,1,1,3,3,3-Hexafluoro-2-propanol.

    PubMed

    Motiwala, Hashim F; Yin, Qin; Aubé, Jeffrey

    2015-12-29

    The Schmidt reaction of aromatic aldehydes using a substoichiometric amount (40 mol %) of triflic acid is described. Low catalyst loading was enabled by a strong hydrogen-bond-donating solvent hexafluoro-2-propanol (HFIP). This improved protocol tolerates a broad scope of aldehydes with diverse functional groups and the corresponding nitriles were obtained in good to high yields without the need for aqueous work up.

  3. Preventive effects of Chlorella on skeletal muscle atrophy in muscle-specific mitochondrial aldehyde dehydrogenase 2 activity-deficient mice.

    PubMed

    Nakashima, Yuya; Ohsawa, Ikuroh; Nishimaki, Kiyomi; Kumamoto, Shoichiro; Maruyama, Isao; Suzuki, Yoshihiko; Ohta, Shigeo

    2014-10-11

    Oxidative stress is involved in age-related muscle atrophy, such as sarcopenia. Since Chlorella, a unicellular green alga, contains various antioxidant substances, we used a mouse model of enhanced oxidative stress to investigate whether Chlorella could prevent muscle atrophy. Aldehyde dehydrogenase 2 (ALDH2) is an anti-oxidative enzyme that detoxifies reactive aldehydes derived from lipid peroxides such as 4-hydroxy-2-nonenal (4-HNE). We therefore used transgenic mice expressing a dominant-negative form of ALDH2 (ALDH2*2 Tg mice) to selectively decrease ALDH2 activity in the muscles. To evaluate the effect of Chlorella, the mice were fed a Chlorella-supplemented diet (CSD) for 6 months. ALDH2*2 Tg mice exhibited small body size, muscle atrophy, decreased fat content, osteopenia, and kyphosis, accompanied by increased muscular 4-HNE levels. The CSD helped in recovery of body weight, enhanced oxidative stress, and increased levels of a muscle impairment marker, creatine phosphokinase (CPK) induced by ALDH2*2. Furthermore, histological and histochemical analyses revealed that the consumption of the CSD improved skeletal muscle atrophy and the activity of the mitochondrial cytochrome c oxidase. This study suggests that long-term consumption of Chlorella has the potential to prevent age-related muscle atrophy.

  4. Cytochrome P450BM-3 reduces aldehydes to alcohols through a direct hydride transfer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kaspera, Ruediger; Sahele, Tariku; Lakatos, Kyle

    Highlights: Black-Right-Pointing-Pointer Cytochrome P450BM-3 reduced aldehydes to alcohols efficiently (k{sub cat} {approx} 25 min{sup -1}). Black-Right-Pointing-Pointer Reduction is a direct hydride transfer from R-NADP{sup 2}H to the carbonyl moiety. Black-Right-Pointing-Pointer P450 domain variants enhance reduction through potential allosteric/redox interactions. Black-Right-Pointing-Pointer Novel reaction will have implications for metabolism of xenobiotics. -- Abstract: Cytochrome P450BM-3 catalyzed the reduction of lipophilic aldehydes to alcohols efficiently. A k{sub cat} of {approx}25 min{sup -1} was obtained for the reduction of methoxy benzaldehyde with wild type P450BM-3 protein which was higher than in the isolated reductase domain (BMR) alone and increased in specific P450-domain variants. Themore » reduction was caused by a direct hydride transfer from preferentially R-NADP{sup 2}H to the carbonyl moiety of the substrate. Weak substrate-P450-binding of the aldehyde, turnover with the reductase domain alone, a deuterium incorporation in the product from NADP{sup 2}H but not D{sub 2}O, and no inhibition by imidazole suggests the reductase domain of P450BM-3 as the potential catalytic site. However, increased aldehyde reduction by P450 domain variants (P450BM-3 F87A T268A) may involve allosteric or redox mechanistic interactions between heme and reductase domains. This is a novel reduction of aldehydes by P450BM-3 involving a direct hydride transfer and could have implications for the metabolism of endogenous substrates or xenobiotics.« less

  5. Biochemical Properties of Purified Human Retinol Dehydrogenase 12 (RDH12): Catalytic Efficiency toward Retinoids and C9 Aldehydes and Effects of Cellular Retinol-Binding Protein Type I (CRBPI) and Cellular Retinaldehyde-Binding Protein (CRALBP) on the Oxidation and Reduction of Retinoids†

    PubMed Central

    Belyaeva, Olga V.; Korkina, Olga V.; Stetsenko, Anton V.; Kim, Tom; Nelson, Peter S.; Kedishvili, Natalia Y.

    2008-01-01

    Retinol dehydrogenase 12 (RDH12) is a novel member of the short-chain dehydrogenase/reductase superfamily of proteins that was recently linked to Leber’s congenital amaurosis 3 (LCA). We report the first biochemical characterization of purified human RDH12 and analysis of its expression in human tissues. RDH12 exhibits ~2000-fold lower Km values for NADP+ and NADPH than for NAD+ and NADH and recognizes both retinoids and lipid peroxidation products (C9 aldehydes) as substrates. The kcat values of RDH12 for retinaldehydes and C9 aldehydes are similar, but the Km values are, in general, lower for retinoids. The enzyme exhibits the highest catalytic efficiency for all-trans-retinal (kcat/Km ~900 min−1 μM−1), followed by 11-cis-retinal (450 min−1 mM−1) and 9-cis-retinal (100 min−1 mM−1). Analysis of RDH12 activity toward retinoids in the presence of cellular retinol-binding protein (CRBP) type I or cellular retinaldehyde-binding protein (CRALBP) suggests that RDH12 utilizes the unbound forms of all-trans- and 11-cis-retinoids. As a result, the widely expressed CRBPI, which binds all-trans-retinol with much higher affinity than all-trans-retinaldehyde, restricts the oxidation of all-trans-retinol by RDH12, but has little effect on the reduction of all-trans-retinaldehyde, and CRALBP inhibits the reduction of 11-cis-retinal stronger than the oxidation of 11-cis-retinol, in accord with its higher affinity for 11-cis-retinal. Together, the tissue distribution of RDH12 and its catalytic properties suggest that, in most tissues, RDH12 primarily contributes to the reduction of all-trans-retinaldehyde; however, at saturating concentrations of peroxidic aldehydes in the cells undergoing oxidative stress, for example, photoreceptors, RDH12 might also play a role in detoxification of lipid peroxidation products. PMID:15865448

  6. Proteomic Analysis of Mitochondria-Enriched Fraction Isolated from the Frontal Cortex and Hippocampus of Apolipoprotein E Knockout Mice Treated with Alda-1, an Activator of Mitochondrial Aldehyde Dehydrogenase (ALDH2).

    PubMed

    Stachowicz, Aneta; Olszanecki, Rafał; Suski, Maciej; Głombik, Katarzyna; Basta-Kaim, Agnieszka; Adamek, Dariusz; Korbut, Ryszard

    2017-02-17

    The role of different genotypes of apolipoprotein E (apoE) in the etiology of Alzheimer's disease is widely recognized. It has been shown that altered functioning of apoE may promote 4-hydroxynonenal modification of mitochondrial proteins, which may result in mitochondrial dysfunction, aggravation of oxidative stress, and neurodegeneration. Mitochondrial aldehyde dehydrogenase (ALDH2) is an enzyme considered to perform protective function in mitochondria by the detoxification of the end products of lipid peroxidation, such as 4-hydroxynonenal and other reactive aldehydes. The goal of our study was to apply a differential proteomics approach in concert with molecular and morphological techniques to elucidate the changes in the frontal cortex and hippocampus of apolipoprotein E knockout (apoE -/- ) mice upon treatment with Alda-1-a small molecular weight activator of ALDH2. Despite the lack of significant morphological changes in the brain of apoE -/- mice as compared to age-matched wild type animals, the proteomic and molecular approach revealed many changes in the expression of genes and proteins, indicating the impairment of energy metabolism, neuroplasticity, and neurogenesis in brains of apoE -/- mice. Importantly, prolonged treatment of apoE -/- mice with Alda-1 led to the beneficial changes in the expression of genes and proteins related to neuroplasticity and mitochondrial function. The pattern of alterations implies mitoprotective action of Alda-1, however, the accurate functional consequences of the revealed changes require further research.

  7. Crosstalk-eliminated quantitative determination of aflatoxin B1-induced hepatocellular cancer stem cells based on concurrent monitoring of CD133, CD44, and aldehyde dehydrogenase1.

    PubMed

    Ju, Hee; Shim, Yumi; Arumugam, Parthasarathy; Song, Joon Myong

    2016-01-22

    Cancer stem cells (CSCs), known as tumor initiating cells, have become a critically important issue for cancer therapy. Although much research has demonstrated the induction of hepato cellular carcinoma by aflatoxin B1, the formation of hepatocellular CSCs and their quantitative determination is hardly reported. In this work, it was found that hepatocellular CSCs were produced from HepG2 cells by aflatoxin B1-induced mutation, and their amount was quantitatively determined using crosstalk-eliminated multicolor cellular imaging based on quantum dot (Qdot) nanoprobes and an acousto-optical tunable filter (AOTF). Hepatocellular CSCs were acquired via magnetic bead-based sorting and observed using concurrent detection of three different markers: CD133, CD44, and aldehyde dehydrogenase1 (ALDH1). The DNA mutation of HepG2 cells caused by aflatoxin B1 was quantitatively observed via absorbance spectra of aflatoxin B1-8, 9-epoxide-DNA adducts. The percentages of hepatocellular CSCs formed in the entire HepG2 cells were determined to be 9.77±0.65%, 10.9±1.39%, 11.4±1.32%, and 12.8±0.7%, respectively, at 0 μM, 5 μM, 10 μM, and 20 μM of aflatoxin B1. The results matched well with those obtained utilizing flow cytometry. This study demonstrates that aflatoxin mediated mutation induced the conversion of hepatic cancer cell to hepatic CSCs by using a Qdot based constructed multicolor cellular imaging system. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Vasodilatory effect of nitroglycerin in Japanese subjects with different aldehyde dehydrogenase 2 (ALDH2) genotypes.

    PubMed

    Miura, Takeshi; Nishinaka, Toru; Terada, Tomoyuki; Yonezawa, Kazuya

    2017-10-01

    The functional genetic polymorphism of aldehyde dehydrogenase 2 (ALDH2) influences the enzymatic activities of its wild type (Glu504 encoded by ALDH2*1) and mutant type (Lys504 encoded by ALDH2*2) proteins. The enzymatic activities of mutant-type ALDH2 are limited compared with those of the wild type. ALDH2 has been suggested as a critical factor for nitroglycerin-mediated vasodilation by some human studies and in vitro studies. Currently, there is no research on direct observations of the vasodilatory effect of nitroglycerin sublingual tablets, which is the generally used dosage form. In the present study, the contribution of ALDH2 to the vasodilatory effect of nitroglycerin sublingual tablets was investigated among three genotype groups (ALDH2*1/*1, ALDH2*1/*2, and ALDH2*2/*2) in Japanese. The results by direct assessments of in vivo nitroglycerin-mediated dilation showed no apparent difference in vasodilation among all genotypes of ALDH2. Furthermore, to analyze the effect of other factors (age and flow-mediated dilation), multiple regression analysis and Pearson's correlation coefficient analysis were carried out. These analyses also indicated that the genotypes of ALDH2 were not related to the degree of vasodilation. These results suggest the existence of other predominant pathway(s) for nitroglycerin biotransformation, at least with regard to clinical nitroglycerin (e.g., a sublingual tablet) in Japanese subjects. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Structural, Biochemical, and Computational Studies Reveal the Mechanism of Selective Aldehyde Dehydrogenase 1A1 Inhibition by Cytotoxic Duocarmycin Analogues.

    PubMed

    Koch, Maximilian F; Harteis, Sabrina; Blank, Iris D; Pestel, Galina; Tietze, Lutz F; Ochsenfeld, Christian; Schneider, Sabine; Sieber, Stephan A

    2015-11-09

    Analogues of the natural product duocarmycin bearing an indole moiety were shown to bind aldehyde dehydrogenase 1A1 (ALDH1A1) in addition to DNA, while derivatives without the indole solely addressed the ALDH1A1 protein. The molecular mechanism of selective ALDH1A1 inhibition by duocarmycin analogues was unraveled through cocrystallization, mutational studies, and molecular dynamics simulations. The structure of the complex shows the compound embedded in a hydrophobic pocket, where it is stabilized by several crucial π-stacking and van der Waals interactions. This binding mode positions the cyclopropyl electrophile for nucleophilic attack by the noncatalytic residue Cys302, thereby resulting in covalent attachment, steric occlusion of the active site, and inhibition of catalysis. The selectivity of duocarmycin analogues for ALDH1A1 is unique, since only minor alterations in the sequence of closely related protein isoforms restrict compound accessibility. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Oxidative damage in keratinocytes exposed to cigarette smoke and aldehydes.

    PubMed

    Avezov, Katia; Reznick, Abraham Z; Aizenbud, Dror

    2014-06-01

    Cigarette smoke (CS) is a significant environmental source of human exposure to chemically active saturated (acetaldehyde) and α,β-unsaturated aldehydes (acrolein) inducing protein carbonylation and dysfunction. The exposure of oral tissues to environmental hazards is immense, especially in smokers. The objectives of the current study were to examine the effect of aldehydes originating from CS on intracellular proteins of oral keratinocytes and to observe the antioxidant response in these cells. Intracellular protein carbonyl modification under CS, acrolein and acetaldehyde exposure in the HaCaT keratinocyte cell line, representing oral keratinocytes was examined by Western blot. Possible intracellular enzymatic dysfunction under the above conditions was examined by lactate dehydrogenase (LDH) activity assay. Oxidative stress response was investigated, by DCF (2,7-dichlorodihydrofluorescein) assay and GSH (glutathione) oxidation. Intracellular protein carbonyls increased 5.2 times after CS exposure and 2.7 times after exposure to 1 μmol of acrolein. DCF assay revealed an increase of fluorescence intensity 3.2 and 3.1 times after CS and acrolein exposure, respectively. CS caused a 72.5% decrease in intracellular GSH levels compared to controls. Activity of intracellular LDH was preserved. α,β-Unsaturated aldehydes from CS are capable of intracellular protein carbonylation and have a role in intracellular oxidative stress elevation in keratinocytes, probably due to the reduction in GSH levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Aldehyde dehydrogenase-2 genotypes and HLA haplotypes in Japanese patients with esophageal cancer.

    PubMed

    Watanabe, Seishiro; Sasahara, Katsuyuki; Kinekawa, Fumihiko; Uchida, Naohito; Masaki, Tsutomu; Kurokohchi, Kazutaka; Murota, Masayuki; Touge, Tetsuo; Kawauchi, Kazuyoshi; Oda, Syuji; Kuriyama, Shigeki

    2002-01-01

    The aim of this study was to examine how aldehyde dehydrogenase-2 (ALDH2) genotypes and human leukocyte antigen (HLA) haplotypes contribute to the risk for esophageal cancer. We examined ALDH2 genotypes and HLA haplotypes in 29 Japanese patients with esophageal cancer. The ratio of patients who experienced current or former intense vasodilatation upon consuming alcohol (flushing type) was much higher in individuals with the inactive form of ALDH2 encoded by the ALDH2(2)/2(2) or ALDH2(1)/2(2) genotype than in those with the active form of ALDH2 encoded by the ALDH2(1)/2(1) genotype. The ratio of inactive ALDH2 was significantly higher in patients with esophageal cancer than in control normal subjects, suggesting that alcoholics with inactive ALDH2 were susceptible to esophageal cancer. HLA haplotypes A24, A26, B54, B61 and DR9 were prevalent in patients with esophageal cancer (82.8, 24.1, 34.5, 37.9 and 44.8%, respectively). HLA haplotype of A24 and inactive ALDH2 were simultaneously found in 58.6% of patients with esophageal cancer. Furthermore, we found other primary malignancies in 6 of 29 (20.7%) patients with esophageal cancer, and 4 of these 6 patients had both the inactive form of ALDH2 and the HLA A24 haplotype. The present study showed the high prevalence of the inactive form of ALDH2 and HLA haplotypes A24, A26, B54, B61 and DR9 in Japanese patients with esophageal cancer. Therefore, the examination of genotypes of ALDH2 loci and HLA haplotypes may allow the early detection of esophageal cancer in the Japanese population.

  12. Cloning, Expression, and Purification of Choline Dehydrogenase from the Moderate Halophile Halomonas elongata

    PubMed Central

    Gadda, Giovanni; McAllister-Wilkins, Elien Elizabeth

    2003-01-01

    Choline dehydrogenase (EC 1.1.99.1) catalyzes the four-electron oxidation of choline to glycine-betaine via a betaine-aldehyde intermediate. Such a reaction is of considerable interest for biotechnological applications in that transgenic plants engineered with bacterial glycine-betaine-synthesizing enzymes have been shown to have enhanced tolerance towards various environmental stresses, such as hypersalinity, freezing, and high temperatures. To date, choline dehydrogenase has been poorly characterized in its biochemical and kinetic properties, mainly because its purification has been hampered by instability of the enzyme in vitro. In the present report, we cloned and expressed in Escherichia coli the betA gene from the moderate halophile Halomonas elongata which codes for a hypothetical choline dehydrogenase. The recombinant enzyme was purified to more than 70% homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by treatment with 30 to 50% saturation of ammonium sulfate followed by column chromatography using DEAE-Sepharose. The purified enzyme showed similar substrate specificities with either choline or betaine-aldehyde as the substrate, as indicated by the apparent V/K values (where V is the maximal velocity and K is the Michaelis constant) of 0.9 and 0.6 μmol of O2 min−1 mg−1 mM−1 at pH 7 and 25°C, respectively. With 1 mM phenazine methosulfate as the primary electron acceptor, the apparent Vmax values for choline and betaine-aldehyde were 10.9 and 5.7 μmol of O2 min−1 mg−1, respectively. These Vmax values decreased four- to sevenfold when molecular oxygen was used as the electron acceptor. Altogether, the kinetic data are consistent with the conclusion that H. elongata betA codes for a choline dehydrogenase that can also act as an oxidase when electron acceptors other than molecular oxygen are not available. PMID:12676692

  13. Origin and dispersal of atypical aldehyde dehydrogenase ALDH2487Lys.

    PubMed

    Luo, Huai-Rong; Wu, Gui-Sheng; Pakstis, Andrew J; Tong, Li; Oota, Hiroki; Kidd, Kenneth K; Zhang, Ya-Ping

    2009-04-15

    The East Asian respond with a marked facial flushing and mild to moderate symptoms of intoxication after drinking the amounts of alcohol that has no detectable effect on European. The alcohol sensitivity in Orientals is due to a delayed oxidation of acetaldehyde by an atypical aldehyde dehydrogenase ALDH2487Lys, which is resulted from a structural mutation in gene ALDH2. The atypical ALDH2487Lys allele has been associated with various phenotypic statuses, such as protective against alcohol dependence and the risk of alcohol-related digestive tract cancers. Here, we have examined this SNP, adjacent four non-coding SNPs, and one downstream STRP on ALDH2 gene, in total of 1072 unrelated healthy individuals from 14 Chinese populations and 130 Indian individuals. Five major haplotypes based on five SNPs across the ALDH2 gene 40 kb were found in all East Asian populations. The frequencies of the ancestral haplotype GCCTG and the East Asian special haplotype GCCTA containing the atypical ALDH2487Lys allele were 44.8% and 14.9%, respectively. The frequency of the atypical ALDH2487Lys allele or the East Asian specific haplotype GCCTA is high in Yunnan, South coastal, east coastal of China, and decreased gradually toward inland China, West, Northwest and North China. Combined with demographic history in East Asian, our results showed that the presence of ALDH2487Lys allele in peripheral regions of China might be the results of historical migration events from China to these regions. The origin of ALDH2487Lys could be possibly traced back to ancient Pai-Yuei tribe in South China.

  14. Analysis of nucleoside-binding proteins by ligand-specific elution from dye resin: application to Mycobacterium tuberculosis aldehyde dehydrogenases.

    PubMed

    Kim, Chang-Yub; Webster, Cecelia; Roberts, Justin K M; Moon, Jin Ho; Alipio Lyon, Emily Z; Kim, Heungbok; Yu, Minmin; Hung, Li-Wei; Terwilliger, Thomas C

    2009-12-01

    We show that Cibacron Blue F3GA dye resin chromatography can be used to identify ligands that specifically interact with proteins from Mycobacterium tuberculosis, and that the identification of these ligands can facilitate structure determination by enhancing the quality of crystals. Four native Mtb proteins of the aldehyde dehydrogenase (ALDH) family were previously shown to be specifically eluted from a Cibacron Blue F3GA dye resin with nucleosides. In this study we characterized the nucleoside-binding specificity of one of these ALDH isozymes (recombinant Mtb Rv0223c) and compared these biochemical results with co-crystallization experiments with different Rv0223c-nucleoside pairings. We found that the strongly interacting ligands (NAD and NADH) aided formation of high-quality crystals, permitting solution of the first Mtb ALDH (Rv0223c) structure. Other nucleoside ligands (AMP, FAD, adenosine, GTP and NADP) exhibited weaker binding to Rv0223c, and produced co-crystals diffracting to lower resolution. Difference electron density maps based on crystals of Rv0223c with various nucleoside ligands show most share the binding site where the natural ligand NAD binds. From the high degree of similarity of sequence and structure compared to human mitochondrial ALDH-2 (BLAST Z-score = 53.5 and RMSD = 1.5 A), Rv0223c appears to belong to the ALDH-2 class. An altered oligomerization domain in the Rv0223c structure seems to keep this protein as monomer whereas native human ALDH-2 is a multimer.

  15. Human Salivary Aldehyde Dehydrogenase: Purification, Kinetic Characterization and Effect of Ethanol, Hydrogen Peroxide and Sodium Dodecyl Sulfate on the Activity of the Enzyme.

    PubMed

    Alam, Md Fazle; Laskar, Amaj Ahmed; Choudhary, Hadi Hasan; Younus, Hina

    2016-09-01

    Human salivary aldehyde dehydrogenase (hsALDH) enzyme appears to be the first line of defense in the body against exogenous toxic aldehydes. However till date much work has not been done on this important member of the ALDH family. In this study, we have purified hsALDH to homogeneity by diethylaminoethyl-cellulose (DEAE-cellulose) ion-exchange chromatography in a single step. The molecular mass of the homodimeric enzyme was determined to be approximately 108 kDa. Four aromatic substrates; benzaldehyde, cinnamaldehyde, 2-naphthaldehyde and 6-methoxy-2-naphthaldehyde were used for determining the activity of pure hsALDH. K m values for these substrates were calculated to be 147.7, 5.31, 0.71 and 3.31 μM, respectively. The best substrates were found to be cinnamaldehyde and 2-naphthaldehyde since they exhibited high V max /K m values. 6-methoxy-2-naphthaldehyde substrate was used for further kinetic characterization of pure hsALDH. The pH and temperature optima of hsALDH were measured to be pH 8 and 45 °C, respectively. The pure enzyme is highly unstable at high temperatures. Ethanol, hydrogen peroxide and SDS activate hsALDH, therefore it is safe and beneficial to include them in mouthwashes and toothpastes in low concentrations.

  16. Optimized dosing schedule based on circadian dynamics of mouse breast cancer stem cells improves the anti-tumor effects of aldehyde dehydrogenase.

    PubMed

    Matsunaga, Naoya; Ogino, Takashi; Hara, Yukinori; Tanaka, Takahiro; Koyanagi, Satoru; Ohdo, Shigehiro

    2018-05-07

    Although malignant phenotypes of triple-negative breast cancer (TNBC) are subject to circadian alterations, the role of cancer stem cells (CSC) in defining this circadian change remains unclear. CSC are often characterized by high aldehyde dehydrogenase (ALDH) activity, which is associated with the malignancy of cancer cells and used for identification and isolation of CSC. Here we show that the popultation of ALDH-positive cells in a mouse 4T1 breast tumor model exhibits pronounced circadian alterations. Alterations in the number of ALDH-positive cells was generated by time-dependent increases and decreases in the expression of Aldh3a1. Importantly, circadian clock genes were rhythmically expressed in ALDH-negative cells, but not in ALDH-positive cells. Circadian expression of Aldh3a1 in ALDH-positive cells was dependent on the time-dependent release of Wingless-type mmtv integration site family 10a (WNT10a) from ALDH-negative cells. Furthermore, anti-tumor and anti-metastatic effects of ALDH inhibitor N,N-diethylaminobenzaldehyde were enhanced by administration at the time of day when ALDH activity was increased in 4T1 tumor cells. Our findings reveal a new role for the circadian clock within the tumor microenvironment in regulating the circadian dynamics of CSC. These results should enable the development of novel therapeutic strategies for treatment of TNBC with ALDH inhibitors. Copyright ©2018, American Association for Cancer Research.

  17. A novel type of pathogen defense-related cinnamyl alcohol dehydrogenase.

    PubMed

    Logemann, E; Reinold, S; Somssich, I E; Hahlbrock, K

    1997-08-01

    We describe an aromatic alcohol dehydrogenase with properties indicating a novel type of function in the defense response of plants to pathogens. To obtain the enzyme free of contamination with possible isoforms, a parsley (Petroselinum crispum) cDNA comprising the entire coding region of the elicitor-responsive gene, ELI3, was expressed in Escherichia coli. In accord with large amino acid sequence similarities with established cinnamyl and benzyl alcohol dehydrogenases from other plants, the enzyme efficiently reduced various cinnamyl and benzyl aldehydes using NADPH as a co-substrate. Highest substrate affinities were observed for cinnamaldehyde, 4-coumaraldehyde and coniferaldehyde, whereas sinapaldehyde, one of the most efficient substrates of several previously analyzed cinnamyl alcohol dehydrogenases and a characteristic precursor molecule of angiosperm lignin, was not converted. A single form of ELI3 mRNA was strongly and rapidly induced in fungal elicitor-treated parsley cells. These results, together with earlier findings that the ELI3 gene is strongly activated both in elicitor-treated parsley cells and at fungal infection sites in parsley leaves, but not in lignifying tissue, suggest a specific role of this enzyme in pathogen defense-related phenylpropanoid metabolism.

  18. Histamine H4-Receptors Inhibit Mast Cell Renin Release in Ischemia/Reperfusion via Protein Kinase Cε-Dependent Aldehyde Dehydrogenase Type-2 Activation

    PubMed Central

    Aldi, Silvia; Takano, Ken-ichi; Tomita, Kengo; Koda, Kenichiro; Chan, Noel Y.-K.; Marino, Alice; Salazar-Rodriguez, Mariselis; Thurmond, Robin L.

    2014-01-01

    Renin released by ischemia/reperfusion (I/R) from cardiac mast cells (MCs) activates a local renin-angiotensin system (RAS) causing arrhythmic dysfunction. Ischemic preconditioning (IPC) inhibits MC renin release and consequent activation of this local RAS. We postulated that MC histamine H4-receptors (H4Rs), being Gαi/o-coupled, might activate a protein kinase C isotype–ε (PKCε)–aldehyde dehydrogenase type-2 (ALDH2) cascade, ultimately eliminating MC-degranulating and renin-releasing effects of aldehydes formed in I/R and associated arrhythmias. We tested this hypothesis in ex vivo hearts, human mastocytoma cells, and bone marrow–derived MCs from wild-type and H4R knockout mice. We found that activation of MC H4Rs mimics the cardioprotective anti-RAS effects of IPC and that protection depends on the sequential activation of PKCε and ALDH2 in MCs, reducing aldehyde-induced MC degranulation and renin release and alleviating reperfusion arrhythmias. These cardioprotective effects are mimicked by selective H4R agonists and disappear when H4Rs are pharmacologically blocked or genetically deleted. Our results uncover a novel cardioprotective pathway in I/R, whereby activation of H4Rs on the MC membrane, possibly by MC-derived histamine, leads sequentially to PKCε and ALDH2 activation, reduction of toxic aldehyde-induced MC renin release, prevention of RAS activation, reduction of norepinephrine release, and ultimately to alleviation of reperfusion arrhythmias. This newly discovered protective pathway suggests that MC H4Rs may represent a new pharmacologic and therapeutic target for the direct alleviation of RAS-induced cardiac dysfunctions, including ischemic heart disease and congestive heart failure. PMID:24696042

  19. Spacecraft Maximum Allowable Concentrations (SMACs) for C3 to C8 Aliphatic Saturated Aldehydes

    NASA Technical Reports Server (NTRS)

    Langford, Shannon D.

    2007-01-01

    Spacecraft maximum allowable concentrations (SMACs) for C3 to C8, straight-chain, aliphatic aldehydes have been previously assessed and have been documented in volume 4 of Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants (James, 2000). These aldehydes as well as associated physical properties are shown in Table 1. The C3 to C8 aliphatic aldehydes can enter the habitable compartments and contaminate breathing air of spacecraft by several routes including incomplete oxidation of alcohols in the Environmental Control and Life Support System (ECLSS) air revitalization subsystem, as a byproduct of human metabolism, through materials off-gassing, or during food preparation. These aldehydes have been detected in the atmosphere of manned space vehicles in the past. Analysis performed by NASA of crew cabin air samples from the Russian Mir Space Station revealed the presence of C3 to C8 aldehydes at concentrations peaking at approximately 0.1 mg/cu m.

  20. Solvent-Free Addition of Indole to Aldehydes: Unexpected Synthesis of Novel 1-[1-(1H-Indol-3-yl) Alkyl]-1H-Indoles and Preliminary Evaluation of Their Cytotoxicity in Hepatocarcinoma Cells.

    PubMed

    Tocco, Graziella; Zedda, Gloria; Casu, Mariano; Simbula, Gabriella; Begala, Michela

    2017-10-17

    New 1-[1-(1 H -indol-3-yl) alkyl]-1 H -indoles, surprisingly, have been obtained from the addition of indole to a variety of aldehydes under neat conditions. CaO, present in excess, was fundamental for carrying out the reaction with paraformaldehyde. Under the same reaction conditions, aromatic and heteroaromatic aldehydes afforded only classical bis (indolyl) aryl indoles. In this paper, the role of CaO, together with the regiochemistry and the mechanism of the reaction, are discussed in detail. The effect of some selected 3,3'- and 1,3'-diindolyl methane derivatives on cell proliferation of the hepatoma cell line FaO was also evaluated.

  1. Functional characterization of SlscADH1, a fruit-ripening-associated short-chain alcohol dehydrogenase of tomato.

    PubMed

    Moummou, Hanane; Tonfack, Libert Brice; Chervin, Christian; Benichou, Mohamed; Youmbi, Emmanuel; Ginies, Christian; Latché, Alain; Pech, Jean-Claude; van der Rest, Benoît

    2012-10-15

    A tomato short-chain dehydrogenase-reductase (SlscADH1) is preferentially expressed in fruit with a maximum expression at the breaker stage while expression in roots, stems, leaves and flowers is very weak. It represents a potential candidate for the formation of aroma volatiles by interconverting alcohols and aldehydes. The SlscADH1 recombinant protein produced in Escherichia coli exhibited dehydrogenase-reductase activity towards several volatile compounds present in tomato flavour with a strong preference for the NAD/NADH co-factors. The strongest activity was observed for the reduction of hexanal (K(m)=0.175mM) and phenylacetaldehyde (K(m)=0.375mM) in the presence of NADH. The oxidation process of hexanol and 1-phenylethanol was much less efficient (K(m)s of 2.9 and 23.0mM, respectively), indicating that the enzyme preferentially acts as a reductase. However activity was observed only for hexanal, phenylacetaldehyde, (E)-2-hexenal and acetaldehyde and the corresponding alcohols. No activity could be detected for other aroma volatiles important for tomato flavour, such as methyl-butanol/methyl-butanal, 5-methyl-6-hepten-2-one/5-methyl-6-hepten-2-ol, citronellal/citronellol, neral/nerol, geraniol. In order to assess the function of the SlscADH1 gene, transgenic plants have been generated using the technique of RNA interference (RNAi). Constitutive down-regulation using the 35S promoter resulted in the generation of dwarf plants, indicating that the SlscADH1 gene, although weakly expressed in vegetative tissues, had a function in regulating plant development. Fruit-specific down-regulation using the 2A11 promoter had no morphogenetic effect and did not alter the aldehyde/alcohol balance of the volatiles compounds produced by the fruit. Nevertheless, SlscADH1-inhibited fruit unexpectedly accumulated higher concentrations of C5 and C6 volatile compounds of the lipoxygenase pathway, possibly as an indirect effect of the suppression of SlscADH1 on the catabolism of

  2. Three-dimensional structure of holo 3 alpha,20 beta-hydroxysteroid dehydrogenase: a member of a short-chain dehydrogenase family.

    PubMed Central

    Ghosh, D; Weeks, C M; Grochulski, P; Duax, W L; Erman, M; Rimsay, R L; Orr, J C

    1991-01-01

    The x-ray structure of a short-chain dehydrogenase, the bacterial holo 3 alpha,20 beta-hydroxysteroid dehydrogenase (EC 1.1.1.53), is described at 2.6 A resolution. This enzyme is active as a tetramer and crystallizes with four identical subunits in the asymmetric unit. It has the alpha/beta fold characteristic of the dinucleotide binding region. The fold of the rest of the subunit, the quaternary structure, and the nature of the cofactor-enzyme interactions are, however, significantly different from those observed in the long-chain dehydrogenases. The architecture of the postulated active site is consistent with the observed stereospecificity of the enzyme and the fact that the tetramer is the active form. There is only one cofactor and one substrate-binding site per subunit; the specificity for both 3 alpha- and 20 beta-ends of the steroid results from the binding of the steroid in two orientations near the same cofactor at the same catalytic site. Images PMID:1946424

  3. Alcohol and aldehyde dehydrogenase polymorphisms and a new strategy for prevention and screening for cancer in the upper aerodigestive tract in East Asians.

    PubMed

    Yokoyama, Akira; Omori, Tai; Yokoyama, Tetsuji

    2010-01-01

    The ethanol in alcoholic beverages and the acetaldehyde associated with alcohol consumption are Group 1 human carcinogens (WHO, International Agency for Research on Cancer). The combination of alcohol consumption, tobacco smoking, the inactive heterozygous aldehyde dehydrogenase-2 genotype (ALDH2*1/*2) and the less-active homozygous alcohol dehydrogenase-1B genotype (ADH1B*1/*1) increases the risk of squamous cell carcinoma (SCC) in the upper aerodigestive tract (UADT) in a multiplicative fashion in East Asians. In addition to being exposed to locally high levels of ethanol, the UADT is exposed to a very high concentration of acetaldehyde from a variety of sources, including that as an ingredient of alcoholic beverages per se and that found in tobacco smoke; acetaldehyde is also produced by salivary microorganisms and mucosal enzymes and is present as blood acetaldehyde. The inefficient degradation of acetaldehyde by weakly expressed ALDH2 in the UADT may be cri! tical to the local accumulation of acetaldehyde, especially in ALDH2*1/*2 carriers. ADH1B*1/*1 carriers tend to experience less intense alcohol flushing and are highly susceptible to heavy drinking and alcoholism. Heavy drinking by persons with the less-active ADH1B*1/*1 leads to longer exposure of the UADT to salivary ethanol and acetaldehyde. The ALDH2*1/*2 genotype is a very strong predictor of synchronous and metachronous multiple SCCs in the UADT. High red cell mean corpuscular volume (MCV), esophageal dysplasia, and melanosis in the UADT, all of which are frequently found in ALDH2*1/*2 drinkers, are useful for identifying high-risk individuals. We invented a simple flushing questionnaire that enables prediction of the ALDH2 phenotype. New health appraisal models that include ALDH2 genotype, the simple flushing questionnaire, or MCV are powerful tools for devising a new strategy for prevention and screening for UADT cancer in East Asians.

  4. Purification of acetaldehyde dehydrogenase and alcohol dehydrogenases from Thermoanaerobacter ethanolicus 39E and characterization of the secondary-alcohol dehydrogenase (2 degrees Adh) as a bifunctional alcohol dehydrogenase--acetyl-CoA reductive thioesterase.

    PubMed Central

    Burdette, D; Zeikus, J G

    1994-01-01

    The purification and characterization of three enzymes involved in ethanol formation from acetyl-CoA in Thermoanaerobacter ethanolicus 39E (formerly Clostridium thermohydrosulfuricum 39E) is described. The secondary-alcohol dehydrogenase (2 degrees Adh) was determined to be a homotetramer of 40 kDa subunits (SDS/PAGE) with a molecular mass of 160 kDa. The 2 degrees Adh had a lower catalytic efficiency for the oxidation of 1 degree alcohols, including ethanol, than for the oxidation of secondary (2 degrees) alcohols or the reduction of ketones or aldehydes. This enzyme possesses a significant acetyl-CoA reductive thioesterase activity as determined by NADPH oxidation, thiol formation and ethanol production. The primary-alcohol dehydrogenase (1 degree Adh) was determined to be a homotetramer of 41.5 kDa (SDS/PAGE) subunits with a molecular mass of 170 kDa. The 1 degree Adh used both NAD(H) and NADP(H) and displayed higher catalytic efficiencies for NADP(+)-dependent ethanol oxidation and NADH-dependent acetaldehyde (identical to ethanal) reduction than for NADPH-dependent acetaldehyde reduction or NAD(+)-dependent ethanol oxidation. The NAD(H)-linked acetaldehyde dehydrogenase was a homotetramer (360 kDa) of identical subunits (100 kDa) that readily catalysed thioester cleavage and condensation. The 1 degree Adh was expressed at 5-20% of the level of the 2 degrees Adh throughout the growth cycle on glucose. The results suggest that the 2 degrees Adh primarily functions in ethanol production from acetyl-CoA and acetaldehyde, whereas the 1 degree Adh functions in ethanol consumption for nicotinamide-cofactor recycling. Images Figure 1 PMID:8068002

  5. AMP-Dependent Kinase and Autophagic Flux are Involved in Aldehyde Dehydrogenase 2-Offered Protection against Cardiac Toxicity of Ethanol

    PubMed Central

    Ge, Wei; Guo, Rui; Ren, Jun

    2011-01-01

    Mitochondrial aldehyde dehydrogenase-2 (ALDH2) alleviates ethanol toxicity although the precise mechanism is unclear. This study was designed to evaluate the effect of ALDH2 on ethanol-induced myocardial damage with a focus on autophagy. Wild-type FVB and transgenic mice overexpressing ALDH2 were challenged with ethanol (3 g/kg/d, i.p.) for 3 days and cardiac mechanical function was assessed using the echocardiographic and IonOptix systems. Western blot analysis was used to evaluate essential autophagy markers, Akt and AMPK and their downstream signaling mTOR. Ethanol challenge altered cardiac geometry and function evidenced by enlarged ventricular end systolic and diastolic diameters, decreased cell shortening and intracellular Ca2+ rise, prolonged relengthening and intracellular Ca2+ decay, as well as reduced SERCA Ca2+ uptake, the effects of which were mitigated by ALDH2. Ethanol challenge facilitated myocardial autophagy as evidenced by enhanced expression of Beclin, ATG7 and LC3B II, as well as mTOR dephosphorylation, which was alleviated by ALDH2. Ethanol challenge-induced cardiac defect and apoptosis were reversed by the ALDH-2 agonist Alda-1, the autophagy inhibitor 3-MA, and the AMPK inhibitor compound C whereas the autophagy inducer rapamycin and the AMPK activator AICAR mimicked or exacerbated ethanol-induced cell injury. Ethanol promoted or suppressed phosphorylation of AMPK and Akt, respectively, in FVB but not ALDH2 murine hearts. Moreover, AICAR nullified Alda-1-induced protection against ethanol-triggered autophagic and functional changes. Ethanol increased GFP-LC3 puncta in H9c2 cells, the effect of which was ablated by Alda-1 and 3-MA. Lysosomal inhibition using bafilomycin A1, E64D and pepstatin A obliterated Alda-1- but not ethanol-induced responses in GFP-LC3 puncta. Our results suggested that ALDH2 protects against ethanol toxicity through altered Akt and AMPK signaling and regulation of autophagic flux. PMID:21871561

  6. Aldehyde dehydrogenase expression in Metaphire posthuma as a bioindicator to monitor heavy metal pollution in soil.

    PubMed

    Panday, Raju; Bhatt, Padam Shekhar; Bhattarai, Tribikram; Shakya, Kumudini; Sreerama, Lakshmaiah

    2016-11-21

    Soil contamination and associated pollution plays a detrimental role in soil flora and fauna. Soil is processed and remodeled by subterranean earthworms, accordingly are referred to as soil chemical engineers. These worms, besides processing carbon and nitrogen, serve as minors for processing metals. In heavy metal contaminated soils, they accumulate heavy metals, which in turn cause altered gene expression, including aldehyde dehydrogenase (ALDH) enzymes. This study explores the possibility of ALDH expression in earthworms as a novel biomarker for the heavy metal contamination of soil. Earthworms cultured in contaminated soils accumulated significantly higher levels of Pb and Cd. Similarly, significantly higher levels of ALDH enzyme activities were observed in earthworms cultured in soils contaminated with Pb and Cd. The ALDH activity was found to be highest in worms cultured in 5 ppm heavy metal contaminated soils. Although, ALDH activities decreased as the heavy metal concentration in soil increased, they were significantly higher when compared to control worms cultured in uncontaminated soils. The accumulation of heavy metal in earthworms measured after 28 days decreased as the heavy metal concentration in soil increased. Levels of ALDH expression correlated with total Pb and Cd concentration in the earthworm tissue. This study showed that the ALDH activity in earthworms could potentially be used as a biomarker to show heavy metal pollution in soil.

  7. Single nucleotide polymorphism detection in aldehyde dehydrogenase 2 (ALDH2) gene using bacterial magnetic particles based on dissociation curve analysis.

    PubMed

    Maruyama, Kohei; Takeyama, Haruko; Nemoto, Etsuo; Tanaka, Tsuyoshi; Yoda, Kiyoshi; Matsunaga, Tadashi

    2004-09-20

    Single nucleotide polymorphism (SNP) detection for aldehyde dehydrogenase 2 (ALDH2) gene based on DNA thermal dissociation curve analysis was successfully demonstrated using an automated system with bacterial magnetic particles (BMPs) by developing a new method for avoiding light scattering caused by nanometer-size particles when using commercially available fluorescent dyes such as FITC, Cy3, and Cy5 as labeling chromophores. Biotin-labeled PCR products in ALDH2, two allele-specific probes (Cy3-labeled detection probe for ALDH2*1 and Cy5-labeled detection probe for ALDH2*2), streptavidin-immobilized BMPs (SA-BMPs) were simultaneously mixed. The mixture was denatured at 70 degrees C for 3 min, cooled slowly to 25 degrees C, and incubated for 10 min, allowing the DNA duplex to form between Cy3- or Cy5-labeled detection probes and biotin-labeled PCR products on SA-BMPs. Then duplex DNA-BMP complex was heated to 58 degrees C, a temperature determined by dissociation curve analysis and a dissociated single-base mismatched detection probe was removed at the same temperature under precise control. Furthermore, fluorescence signal from the detection probe was liberated into the supernatant from completely matched duplex DNA-BMP complex by heating to 80 degrees C and measured. In the homozygote target DNA (ALDH2*1/*1 and ALDH2*2/*2), the fluorescence signals from single-base mismatched were decreased to background level, indicating that mismatched hybridization was efficiently removed by the washing process. In the heterozygote target DNA (ALDH2*1/*2), each fluorescence signals was at a similar level. Therefore, three genotypes of SNP in ALDH2 gene were detected using the automated detection system with BMPs. Copyright 2004 Wiley Periodicals, Inc.

  8. Hypoglycemic drugs induce antioxidant aldehyde dehydrogenase activity and remain high in patients with glycemic control in type 2 diabetes.

    PubMed

    Picazo, Alejandra; Jiménez-Osorio, Angélica S; Zúñiga-Mejía, Porfirio; Pedraza-Chaverri, José; Monroy, Adriana; Rodríguez-Arellano, M Eunice; Barrera-Oviedo, Diana

    2017-04-05

    The antioxidant system results essential to control and prevent lipid peroxidation due to stress damage in type 2 diabetes. An example is aldehyde dehydrogenase (ALDH), an enzyme that is involved in the detoxification of aldehydes formed during lipid peroxidation. This study was conducted to evaluate ALDH activity and to determine their association with hypoglycemic treatment in type 2 diabetes patients. The study population consisted of 422 Mexican subjects: a control group and type 2 diabetes patients. Type 2 diabetes patients were re-classified as those with or without hypoglycemic treatment and those with or without glycemic control (according to glycated hemoglobin (HbA1c)). Clinical parameters, antioxidant enzyme activities (ALDH, superoxide dismutase (SOD), catalase and glutathione peroxidase) and oxidative markers (reactive oxygen species and thiobarbituric acid reactive substances (TBARS)) were evaluated. The activity of antioxidant enzymes and oxidative stress markers were higher in type 2 diabetes patients with hypoglycemic treatment and without glycemic control than control group. The activity of ALDH and SOD remained high in type 2 diabetes patients with moderate glycemic control while only ALDH's remained high in type 2 diabetes patients with tight glycemic control. Increased ALDH and SOD activities were associated with hypoglycemic therapy. TBARS levels were associated with glycemic control. The persistence of high ALDH and SOD activities in type 2 diabetes patients with glycemic control may be to avoid a significant damage due to the increase in reactive oxygen species and TBARS. It is possible that this new oxidative status prevented the development the classical complications of diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Development and validation of a rapid, aldehyde dehydrogenase bright–based cord blood potency assay

    PubMed Central

    Noldner, Pamela; Troy, Jesse D.; Cheatham, Lynn; Parrish, Amanda; Page, Kristin; Gentry, Tracy; Balber, Andrew E.; Kurtzberg, Joanne

    2016-01-01

    Banked, unrelated umbilical cord blood provides access to hematopoietic stem cell transplantation for patients lacking matched bone marrow donors, yet 10% to 15% of patients experience graft failure or delayed engraftment. This may be due, at least in part, to inadequate potency of the selected cord blood unit (CBU). CBU potency is typically assessed before cryopreservation, neglecting changes in potency occurring during freezing and thawing. Colony-forming units (CFUs) have been previously shown to predict CBU potency, defined as the ability to engraft in patients by day 42 posttransplant. However, the CFU assay is difficult to standardize and requires 2 weeks to perform. Consequently, we developed a rapid multiparameter flow cytometric CBU potency assay that enumerates cells expressing high levels of the enzyme aldehyde dehydrogenase (ALDH bright [ALDHbr]), along with viable CD45+ or CD34+ cell content. These measurements are made on a segment that was attached to a cryopreserved CBU. We validated the assay with prespecified criteria testing accuracy, specificity, repeatability, intermediate precision, and linearity. We then prospectively examined the correlations among ALDHbr, CD34+, and CFU content of 3908 segments over a 5-year period. ALDHbr (r = 0.78; 95% confidence interval [CI], 0.76-0.79), but not CD34+ (r = 0.25; 95% CI, 0.22-0.28), was strongly correlated with CFU content as well as ALDHbr content of the CBU. These results suggest that the ALDHbr segment assay (based on unit characteristics measured before release) is a reliable assessment of potency that allows rapid selection and release of CBUs from the cord blood bank to the transplant center for transplantation. PMID:26968535

  10. Fatty Aldehyde and Fatty Alcohol Metabolism: Review and Importance for Epidermal Structure and Function

    PubMed Central

    Rizzo, William B.

    2014-01-01

    Normal fatty aldehyde and alcohol metabolism is essential for epidermal differentiation and function. Long-chain aldehydes are produced by catabolism of several lipids including fatty alcohols, sphingolipids, ether glycerolipids, isoprenoid alcohols and certain aliphatic lipids that undergo α- or ω-oxidation. The fatty aldehyde generated by these pathways is chiefly metabolized to fatty acid by fatty aldehyde dehydrogenase (FALDH, alternately known as ALDH3A2), which also functions to oxidize fatty alcohols as a component of the fatty alcohol:NAD oxidoreductase (FAO) enzyme complex. Genetic deficiency of FALDH/FAO in patients with Sjögren-Larsson syndrome (SLS) results in accumulation of fatty aldehydes, fatty alcohols and related lipids (ether glycerolipids, wax esters) in cultured keratinocytes. These biochemical changes are associated with abnormalities in formation of lamellar bodies in the stratum granulosum and impaired delivery of their precursor membranes to the stratum corneum (SC). The defective extracellular SC membranes are responsible for a leaky epidermal water barrier and ichthyosis. Although lamellar bodies appear to be the pathogenic target for abnormal fatty aldehyde/alcohol metabolism in SLS, the precise biochemical mechanisms are yet to be elucidated. Nevertheless, studies in SLS highlight the critical importance of FALDH and normal fatty aldehyde/alcohol metabolism for epidermal function. PMID:24036493

  11. Asymmetric functional organozinc additions to aldehydes catalyzed by 1,1'-bi-2-naphthols (BINOLs).

    PubMed

    Pu, Lin

    2014-05-20

    Chiral alcohols are ubiquitous in organic structures. One efficient method to generate chiral alcohols is the catalytic asymmetric addition of a carbon nucleophile to a carbonyl compound since this process produces a C-C bond and a chiral center simultaneously. In comparison with the carbon nucleophiles such as an organolithium or a Grignard reagent, an organozinc reagent possesses the advantages of functional group tolerance and more mild reaction conditions. Catalytic asymmetric reactions of aldehydes with arylzincs, vinylzincs, and alkynylzincs to generate functional chiral alcohols are discussed in this Account. Our laboratory has developed a series of 1,1'-bi-2-naphthol (BINOL)-based chiral catalysts for the asymmetric organozinc addition to aldehydes. It is found that the 3,3'-dianisyl-substituted BINOLs are not only highly enantioselective for the alkylzinc addition to aldehydes, but also highly enantioselective for the diphenylzinc addition to aldehydes. A one-step synthesis has been achieved to incorporate Lewis basic amine groups into the 3,3'-positions of the partially hydrogenated H8BINOL. These H8BINOL-amine compounds have become more generally enantioselective and efficient catalysts for the diphenylzinc addition to aldehydes to produce various types of chiral benzylic alcohols. The application of the H8BINOL-amine catalysts is expanded by using in situ generated diarylzinc reagents from the reaction of aryl iodides with ZnEt2, which still gives high enantioselectivity and good catalytic activity. Such a H8BINOL-amine compound is further found to catalyze the highly enantioselective addition of vinylzincs, in situ generated from the treatment of vinyl iodides with ZnEt2, to aldehydes to give the synthetically very useful chiral allylic alcohols. We have discovered that the unfunctionalized BINOL in combination with ZnEt2 and Ti(O(i)Pr)4 can catalyze the terminal alkyne addition to aldehydes to produce chiral propargylic alcohols of high synthetic

  12. Inhibition of human cytochrome P450 2E1 and 2A6 by aldehydes: structure and activity relationships.

    PubMed

    Kandagatla, Suneel K; Mack, Todd; Simpson, Sean; Sollenberger, Jill; Helton, Eric; Raner, Gregory M

    2014-08-05

    The purpose of this study was to probe active site structure and dynamics of human cytochrome P4502E1 and P4502A6 using a series of related short chain fatty aldehydes. Binding efficiency of the aldehydes was monitored via their ability to inhibit the binding and activation of the probe substrates p-nitrophenol (2E1) and coumarin (2A6). Oxidation of the aldehydes was observed in reactions with individually expressed 2E1, but not 2A6, suggesting alternate binding modes. For saturated aldehydes the optimum chain length for inhibition of 2E1 was 9 carbons (KI=7.8 ± 0.3 μM), whereas for 2A6 heptanal was most potent (KI=15.8 ± 1.1 μM). A double bond in the 2-position of the aldehyde significantly decreased the observed KI relative to the corresponding saturated compound in most cases. A clear difference in the effect of the double bond was observed between the two isoforms. With 2E1, the double bond appeared to remove steric constraints on aldehyde binding with KI values for the 5-12 carbon compounds ranging between 2.6 ± 0.1 μM and 12.8 ± 0.5 μM, whereas steric effects remained the dominant factor in the binding of the unsaturated aldehydes to 2A6 (observed KI values between 7.0 ± 0.5 μM and >1000 μM). The aldehyde function was essential for effective inhibition, as the corresponding carboxylic acids had very little effect on enzyme activity over the same range of concentrations, and branching at the 3-position of the aldehydes increased the corresponding KI value in all cases examined. The results suggest that a conjugated π-system may be a key structural determinant in the binding of these compounds to both enzymes, and may also be an important feature for the expansion of the active site volume in 2E1. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Inhibition of human Cytochrome P450 2E1 and 2A6 by aldehydes: Structure and activity relationships

    PubMed Central

    Kandagatla, Suneel K.; Mack, Todd; Simpson, Sean; Sollenberger, Jill; Helton, Eric; Raner, Gregory M.

    2014-01-01

    The purpose of this study was to probe active site structure and dynamics of human cytochrome P4502E1 and P4502A6 using a series of related short chain fatty aldehydes. Binding efficiency of the aldehydes was monitored via their ability to inhibit the binding and activation of the probe substrates p-nitrophenol (2E1) and coumarin (2A6). Oxidation of the aldehydes was observed in reactions with individually expressed 2E1, but not 2A6, suggesting alternate binding modes. For saturated aldehydes the optimum chain length for inhibition of 2E1 was 9 carbons (KI=7.8 ±0.3 μM), whereas for 2A6 heptanal was most potent (KI=15.8 ±1.1 μM). A double bond in the 2-position of the aldehyde significantly decreased the observed KI relative to the corresponding saturated compound in most cases. A clear difference in the effect of the double bond was observed between the two isoforms. With 2E1, the double bond appeared to remove steric constraints on aldehyde binding with KI values for the 5–12 carbon compounds ranging between 2.6 ± 0.1 μM and 12.8± 0.5 μM, whereas steric effects remained the dominant factor in the binding of the unsaturated aldehydes to 2A6 (observed KI values between 7.0± 0.5 μM and >1000 μM). The aldehyde function was essential for effective inhibition, as the corresponding carboxylic acids had very little effect on enzyme activity over the same range of concentrations, and branching at the 3-position of the aldehydes increased the corresponding KI value in all cases examined. The results suggest that a conjugated π-system may be a key structural determinant in the binding of these compounds to both enzymes, and may also be an important feature for the expansion of the active site volume in 2E1. PMID:24924949

  14. Resolution and partial characterization of two aldehyde reductases of mammalian liver.

    PubMed

    Tulsiani, D R; Touster

    1977-04-25

    Investigation of NADP-dependent aldehyde reductase activity in mouse liver led to the finding that two distinct reductases are separable by DE52 ion exchange chromatography. Aldehyde reductase I (AR I) appears in the effluent, while aldehyde reductase II (AR II) is eluted with a salt gradient. By several procedures AR II was purified over 1100-fold from liver supernatant fraction, but AR I could be pruified only 107-fold because of its instability. The two enzymes are different in regard to pH optimum, substrate specificity, response to inhibitors, and reactivity with antibody to AR II. While both enzymes utilize aromatic aldehydes well, only AR II ACTS ON D-glucuronate, indicating that it is the aldyhyde reductase recently reported to be identical to NADP-L-gulonate dehydrogenase. The presence of two NADP-linked aldehyde reductases in liver has apparently not heretofore been reported.

  15. Role of a membrane-bound aldehyde dehydrogenase complex AldFGH in acetic acid fermentation with Acetobacter pasteurianus SKU1108.

    PubMed

    Yakushi, Toshiharu; Fukunari, Seiya; Kodama, Tomohiro; Matsutani, Minenosuke; Nina, Shun; Kataoka, Naoya; Theeragool, Gunjana; Matsushita, Kazunobu

    2018-05-01

    Acetic acid fermentation is widely considered a consequence of ethanol oxidation by two membrane-bound enzymes-alcohol dehydrogenase and aldehyde dehydrogenase (ALDH)-of acetic acid bacteria. Here, we used a markerless gene disruption method to construct a mutant of the Acetobacter pasteurianus strain SKU1108 with a deletion in the aldH gene, which encodes the large catalytic subunit of a heterotrimeric ALDH complex (AldFGH), to examine the role of AldFGH in acetic acid fermentation. The ΔaldH strain grew less on ethanol-containing medium, i.e., acetic acid fermentation conditions, than the wild-type strain and significantly accumulated acetaldehyde in the culture medium. Unexpectedly, acetaldehyde oxidase activity levels of the intact ΔaldH cells and the ΔaldH cell membranes were similar to those of the wild-type strain, which might be attributed to an additional ALDH isozyme (AldSLC). The apparent K M values of the wild-type and ΔaldH membranes for acetaldehyde were similar to each other, when the cells were cultured in nonfermentation conditions, where ΔaldH cells grow as well as the wild-type cells. However, the membranes of the wild-type cells grown under fermentation conditions showed a 10-fold lower apparent K M value than those of the cells grown under nonfermentation conditions. Under fermentation conditions, transcriptional levels of a gene for AldSLC were 10-fold lower than those under nonfermentation conditions, whereas aldH transcript levels were not dramatically changed under the two conditions. We suggest that A. pasteurianus SKU1108 has two ALDHs, and the AldFGH complex is indispensable for acetic acid fermentation and is the major enzyme under fermentation conditions.

  16. Direct enzyme assay evidence confirms aldehyde reductase function of Ydr541cp and Ygl039wp from Saccharomyces cerevisiae

    USDA-ARS?s Scientific Manuscript database

    Aldehyde reductase gene ARI1 is a recently characterized member of intermediate subfamily under SDR (short-chain dehydrogenase/reductase) superfamily that revealed mechanisms of in situ detoxification of furfural and HMF for tolerance of Saccharomyces cerevisiae. Uncharacterized open reading frames ...

  17. Development and validation of a rapid, aldehyde dehydrogenase bright-based cord blood potency assay.

    PubMed

    Shoulars, Kevin; Noldner, Pamela; Troy, Jesse D; Cheatham, Lynn; Parrish, Amanda; Page, Kristin; Gentry, Tracy; Balber, Andrew E; Kurtzberg, Joanne

    2016-05-12

    Banked, unrelated umbilical cord blood provides access to hematopoietic stem cell transplantation for patients lacking matched bone marrow donors, yet 10% to 15% of patients experience graft failure or delayed engraftment. This may be due, at least in part, to inadequate potency of the selected cord blood unit (CBU). CBU potency is typically assessed before cryopreservation, neglecting changes in potency occurring during freezing and thawing. Colony-forming units (CFUs) have been previously shown to predict CBU potency, defined as the ability to engraft in patients by day 42 posttransplant. However, the CFU assay is difficult to standardize and requires 2 weeks to perform. Consequently, we developed a rapid multiparameter flow cytometric CBU potency assay that enumerates cells expressing high levels of the enzyme aldehyde dehydrogenase (ALDH bright [ALDH(br)]), along with viable CD45(+) or CD34(+) cell content. These measurements are made on a segment that was attached to a cryopreserved CBU. We validated the assay with prespecified criteria testing accuracy, specificity, repeatability, intermediate precision, and linearity. We then prospectively examined the correlations among ALDH(br), CD34(+), and CFU content of 3908 segments over a 5-year period. ALDH(br) (r = 0.78; 95% confidence interval [CI], 0.76-0.79), but not CD34(+) (r = 0.25; 95% CI, 0.22-0.28), was strongly correlated with CFU content as well as ALDH(br) content of the CBU. These results suggest that the ALDH(br) segment assay (based on unit characteristics measured before release) is a reliable assessment of potency that allows rapid selection and release of CBUs from the cord blood bank to the transplant center for transplantation. © 2016 by The American Society of Hematology.

  18. [1,5]-Anion relay via intramolecular proton transfer to generate 3,3-bis(silyl) allyloxy lithium: a useful scaffold for syn-addition to aldehydes and ketones.

    PubMed

    Lin, Xinglong; Ye, Xincui; Sun, Xianwei; Zhang, Yuebao; Gao, Lu; Song, Zhenlei

    2014-02-21

    A [1,5]-anion relay has been achieved in 3,3-bis(silyl) benzyl enol ether. Deprotonation at the sterically more accessible benzyl position triggers an intramolecular proton transfer to generate the thermodynamically more stable 3,3-bis(silyl) allyloxy lithium. This endo-oriented allyl anion is stable at -78 °C and undergoes diastereoselective syn-addition at the γ-position with aldehydes and ketones to give monobenzyl-substituted 1,2-diols.

  19. Unexpected formation of (E)-4-alkene 1,3-diketones from the three-component reaction of lithium selenolates with 1-(1-alkynyl)cyclopropyl ketones and aldehydes.

    PubMed

    Xu, Jianfeng; Wu, Luling; Huang, Xian

    2011-07-15

    A novel three-component stereoselective synthesis of (E)-4-alkene 1,3-diketones from lithium selenolates, 1-(1-alkynyl)cyclopropyl ketones, and aldehydes is reported. This reaction afforded the products in moderate to good yields with the formation of a new C-Se single bond, a new C-C double bond, and a new C-O double bond.

  20. Cloning, sequencing, and expression of the Pseudomonas testosteroni gene encoding 3-oxosteroid delta 1-dehydrogenase.

    PubMed Central

    Plesiat, P; Grandguillot, M; Harayama, S; Vragar, S; Michel-Briand, Y

    1991-01-01

    Pseudomonas testosteroni ATCC 17410 is able to grow on testosterone. This strain was mutagenized by Tn5, and 41 mutants defective in the utilization of testosterone were isolated. One of them, called mutant 06, expressed 3-oxosteroid delta 1- and 3-oxosteroid delta 4-5 alpha-dehydrogenases only at low levels. The DNA region around the Tn5 insertion in mutant 06 was cloned into pUC19, and the 1-kbp EcoRI-BamHI segment neighbor to the Tn5 insertion was used to probe DNA from the wild-type strain. The probe hybridized to a 7.8-kbp SalI fragment. Plasmid pTES5, which is a pUC19 derivative containing this 7.8-kbp SalI fragment, was isolated after the screening by the 1-kbp EcoRI-BamHI probe. This plasmid expressed delta 1-dehydrogenase in Escherichia coli cells. The 2.2-kbp KpnI-KpnI segment of pTES5 was subcloned into pUC18, and pTEK21 was constructed. In E. coli containing the lacIq plasmid pRG1 and pTEK21, the expression of delta 1-dehydrogenase was induced by isopropyl-beta-D-thiogalactopyranoside (IPTG). The induced level was about 40 times higher than the induced level in P. testosteroni. Delta 1-Dehydrogenase synthesized in E. coli was localized in the inner membrane fraction. The minicell experiments showed that a 59-kDa polypeptide was synthesized from pTEK21, and this polypeptide was located in the inner membrane fraction. The complete nucleotide sequence of the 2.2-kbp KpnI-KpnI segment of pTEK21 was determined. An open reading frame which encodes a 62.4-kDa polypeptide and which is preceded by a Shine-Dalgarno-like sequence was identified. The first 44 amino acids of the putative product exhibited significant sequence similarity to the N-terminal sequences of lipoamide dehydrogenases. Images FIG. 4 PMID:1657885

  1. Genome-wide identification and analysis of the aldehyde dehydrogenase (ALDH) gene superfamily in apple (Malus × domestica Borkh.).

    PubMed

    Li, Xiaoqin; Guo, Rongrong; Li, Jun; Singer, Stacy D; Zhang, Yucheng; Yin, Xiangjing; Zheng, Yi; Fan, Chonghui; Wang, Xiping

    2013-10-01

    Aldehyde dehydrogenases (ALDHs) represent a protein superfamily encoding NAD(P)(+)-dependent enzymes that oxidize a wide range of endogenous and exogenous aliphatic and aromatic aldehydes. In plants, they are involved in many biological processes and play a role in the response to environmental stress. In this study, a total of 39 ALDH genes from ten families were identified in the apple (Malus × domestica Borkh.) genome. Synteny analysis of the apple ALDH (MdALDH) genes indicated that segmental and tandem duplications, as well as whole genome duplications, have likely contributed to the expansion and evolution of these gene families in apple. Moreover, synteny analysis between apple and Arabidopsis demonstrated that several MdALDH genes were found in the corresponding syntenic blocks of Arabidopsis, suggesting that these genes appeared before the divergence of lineages that led to apple and Arabidopsis. In addition, phylogenetic analysis, as well as comparisons of exon-intron and protein structures, provided further insight into both their evolutionary relationships and their putative functions. Tissue-specific expression analysis of the MdALDH genes demonstrated diverse spatiotemporal expression patterns, while their expression profiles under abiotic stress and various hormone treatments indicated that many MdALDH genes were responsive to high salinity and drought, as well as different plant hormones. This genome-wide identification, as well as characterization of evolutionary relationships and expression profiles, of the apple MdALDH genes will not only be useful for the further analysis of ALDH genes and their roles in stress response, but may also aid in the future improvement of apple stress tolerance. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  2. Aldehyde dehydrogenase, Ald4p, is a major component of mitochondrial fluorescent inclusion bodies in the yeast Saccharomyces cerevisiae

    PubMed Central

    Misonou, Yoshiko; Kikuchi, Maiko; Sato, Hiroshi; Inai, Tomomi; Kuroiwa, Tsuneyoshi; Tanaka, Kenji; Miyakawa, Isamu

    2014-01-01

    ABSTRACT When Saccharomyces cerevisiae strain 3626 was cultured to the stationary phase in a medium that contained glucose, needle-like structures that emitted autofluorescence were observed in almost all cells by fluorescence microscopy under UV excitation. The needle-like structures completely overlapped with the profile of straight elongated mitochondria. Therefore, these structures were designated as mitochondrial fluorescent inclusion bodies (MFIBs). The MFIB-enriched mitochondrial fractions were successfully isolated and 2D-gel electrophoresis revealed that a protein of 54 kDa was only highly concentrated in the fractions. Determination of the N-terminal amino acid sequence of the 54-kDa protein identified it as a mitochondrial aldehyde dehydrogenase, Ald4p. Immunofluorescence microscopy showed that anti-Ald4p antibody specifically stained MFIBs. Freeze-substitution electron microscopy demonstrated that cells that retained MFIBs had electron-dense filamentous structures with a diameter of 10 nm in straight elongated mitochondria. Immunoelectron microscopy showed that Ald4p was localized to the electron-dense filamentous structures in mitochondria. These results together showed that a major component of MFIBs is Ald4p. In addition, we demonstrate that MFIBs are common features that appear in mitochondria of many species of yeast. PMID:24771619

  3. Asymmetric Functional Organozinc Additions to Aldehydes Catalyzed by 1,1′-Bi-2-naphthols (BINOLs)†

    PubMed Central

    2015-01-01

    Conspectus Chiral alcohols are ubiquitous in organic structures. One efficient method to generate chiral alcohols is the catalytic asymmetric addition of a carbon nucleophile to a carbonyl compound since this process produces a C–C bond and a chiral center simultaneously. In comparison with the carbon nucleophiles such as an organolithium or a Grignard reagent, an organozinc reagent possesses the advantages of functional group tolerance and more mild reaction conditions. Catalytic asymmetric reactions of aldehydes with arylzincs, vinylzincs, and alkynylzincs to generate functional chiral alcohols are discussed in this Account. Our laboratory has developed a series of 1,1′-bi-2-naphthol (BINOL)-based chiral catalysts for the asymmetric organozinc addition to aldehydes. It is found that the 3,3′-dianisyl-substituted BINOLs are not only highly enantioselective for the alkylzinc addition to aldehydes, but also highly enantioselective for the diphenylzinc addition to aldehydes. A one-step synthesis has been achieved to incorporate Lewis basic amine groups into the 3,3′-positions of the partially hydrogenated H8BINOL. These H8BINOL–amine compounds have become more generally enantioselective and efficient catalysts for the diphenylzinc addition to aldehydes to produce various types of chiral benzylic alcohols. The application of the H8BINOL–amine catalysts is expanded by using in situ generated diarylzinc reagents from the reaction of aryl iodides with ZnEt2, which still gives high enantioselectivity and good catalytic activity. Such a H8BINOL–amine compound is further found to catalyze the highly enantioselective addition of vinylzincs, in situ generated from the treatment of vinyl iodides with ZnEt2, to aldehydes to give the synthetically very useful chiral allylic alcohols. We have discovered that the unfunctionalized BINOL in combination with ZnEt2 and Ti(OiPr)4 can catalyze the terminal alkyne addition to aldehydes to produce chiral propargylic alcohols

  4. 3D-QSAR and docking studies on 1-hydroxypyridin-2-one compounds as mutant isocitrate dehydrogenase 1 inhibitors

    NASA Astrophysics Data System (ADS)

    Wang, Zhenya; Chang, Yiqun; Han, Yushui; Liu, Kangjia; Hou, Jinsong; Dai, Chengli; Zhai, Yuanhao; Guo, Jialiang; Sun, Pinghua; Lin, Jing; Chen, Weimin

    2016-11-01

    Mutation of isocitrate dehydrogenase 1 (IDH1) which is frequently found in certain cancers such as glioma, sarcoma and acute myeloid leukemia, has been proven to be a potent drug target for cancer therapy. In silico methodologies such as 3D-QSAR and molecular docking were performed to explore compounds with better mutant isocitrate dehydrogenase 1 (MIDH1) inhibitory activity using a series of 40 newly reported 1-hydroxypyridin-2-one compounds as MIDH1 inhibitors. The satisfactory CoMFA and CoMSIA models obtained after internal and external cross-validation gave q2 values of 0.691 and 0.535, r2 values of 0.984 and 0.936, respectively. 3D contour maps generated from CoMFA and CoMSIA along with the docking results provided information about the structural requirements for better MIDH1 inhibitory activity. Based on the structure-activity relationship, 17 new potent molecules with better predicted activity than the most active compound in the literature have been designed.

  5. Bioactivation to an aldehyde metabolite--possible role in the onset of toxicity induced by the anti-HIV drug abacavir.

    PubMed

    Grilo, Nádia M; Charneira, Catarina; Pereira, Sofia A; Monteiro, Emília C; Marques, M Matilde; Antunes, Alexandra M M

    2014-01-30

    Aldehydes are highly reactive molecules, which can be generated during numerous physiological processes, including the biotransformation of drugs. Several non-P450 enzymes participate in their metabolism albeit alcohol dehydrogenase and aldehyde dehydrogenase are the ones most frequently involved in this process. Endogenous and exogenous aldehydes have been strongly implicated in multiple human pathologies. Their ability to react with biomacromolecules (e.g. proteins) yielding covalent adducts is suggested to be the common primary mechanism underlying the toxicity of these reactive species. Abacavir is one of the options for combined anti-HIV therapy. Although individual susceptibilities to adverse effects differ among patients, abacavir is associated with idiosyncratic hypersensitivity drug reactions and an increased risk of cardiac dysfunction. This review highlights the current knowledge on abacavir metabolism and discusses the potential role of bioactivation to an aldehyde metabolite, capable of forming protein adducts, in the onset of abacavir-induced toxic outcomes. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  6. The Involvement of Lipid Peroxide-Derived Aldehydes in Aluminum Toxicity of Tobacco Roots1[W][OA

    PubMed Central

    Yin, Lina; Mano, Jun'ichi; Wang, Shiwen; Tsuji, Wataru; Tanaka, Kiyoshi

    2010-01-01

    Oxidative injury of the root elongation zone is a primary event in aluminum (Al) toxicity in plants, but the injuring species remain unidentified. We verified the hypothesis that lipid peroxide-derived aldehydes, especially highly electrophilic α,β-unsaturated aldehydes (2-alkenals), participate in Al toxicity. Transgenic tobacco (Nicotiana tabacum) overexpressing Arabidopsis (Arabidopsis thaliana) 2-alkenal reductase (AER-OE plants), wild-type SR1, and an empty vector-transformed control line (SR-Vec) were exposed to AlCl3 on their roots. Compared with the two controls, AER-OE plants suffered less retardation of root elongation under AlCl3 treatment and showed more rapid regrowth of roots upon Al removal. Under AlCl3 treatment, the roots of AER-OE plants accumulated Al and H2O2 to the same levels as did the sensitive controls, while they accumulated lower levels of aldehydes and suffered less cell death than SR1 and SR-Vec roots. In SR1 roots, AlCl3 treatment markedly increased the contents of the highly reactive 2-alkenals acrolein, 4-hydroxy-(E)-2-hexenal, and 4-hydroxy-(E)-2-nonenal and other aldehydes such as malondialdehyde and formaldehyde. In AER-OE roots, accumulation of these aldehydes was significantly less. Growth of the roots exposed to 4-hydroxy-(E)-2-nonenal and (E)-2-hexenal were retarded more in SR1 than in AER-OE plants. Thus, the lipid peroxide-derived aldehydes, formed downstream of reactive oxygen species, injured root cells directly. Their suppression by AER provides a new defense mechanism against Al toxicity. PMID:20023145

  7. YKL071W from Saccharomyces cerevisiae encodes a novel aldehyde reductase for detoxification of glycolaldehyde and furfural derived from lignocellulose.

    PubMed

    Wang, Hanyu; Ouyang, Yidan; Zhou, Chang; Xiao, Difan; Guo, Yaping; Wu, Lan; Li, Xi; Gu, Yunfu; Xiang, Quanju; Zhao, Ke; Yu, Xiumei; Zou, Likou; Ma, Menggen

    2017-12-01

    Aldehydes generated as by-products during the pretreatment of lignocellulose are the key inhibitors to Saccharomyces cerevisiae, which is considered as the most promising microorganism for industrial production of biofuel, xylitol as well as other special chemicals from lignocellulose. S. cerevisiae has the inherent ability to in situ detoxify aldehydes to corresponding alcohols by multiple aldehyde reductases. Herein, we report that an uncharacterized open reading frame YKL071W from S. cerevisiae encodes a novel "classical" short-chain dehydrogenase/reductase (SDR) protein with NADH-dependent enzymatic activities for reduction of furfural (FF), glycolaldehyde (GA), formaldehyde (FA), and benzaldehyde (BZA). This enzyme showed much better specific activities for reduction of GA and FF than FA and BZA, and displayed much higher Km and Kcat/Km but lower Vmax and Kcat for reduction of GA than FF. For this enzyme, the optimum pH was 5.5 and 6.0 for reduction of GA and FF, and the optimum temperature was 30 °C for reduction of GA and FF. Both pH and temperature affected stability of this enzyme in a similar trend for reduction of GA and FF. Cu 2+ , Zn 2+ , Ni 2+ , and Fe 3+ had severe inhibition effects on enzyme activities of Ykl071wp for reduction of GA and FF. Transcription of YKL071W in S. cerevisiae was significantly upregulated under GA and FF stress conditions, and its transcription is most probably regulated by transcription factor genes of YAP1, CAD1, PDR3, and STB5. This research provides guidelines to identify more uncharacterized genes with reductase activities for detoxification of aldehydes derived from lignocellulose in S. cerevisiae.

  8. Revascularization of ischemic limbs after transplantation of human bone marrow cells with high aldehyde dehydrogenase activity

    PubMed Central

    Capoccia, Benjamin J.; Robson, Debra L.; Levac, Krysta D.; Maxwell, Dustin J.; Hohm, Sarah A.; Neelamkavil, Marian J.; Bell, Gillian I.; Xenocostas, Anargyros; Link, Daniel C.; Piwnica-Worms, David; Nolta, Jan A.

    2009-01-01

    The development of cell therapies to treat peripheral vascular disease has proven difficult because of the contribution of multiple cell types that coordinate revascularization. We characterized the vascular regenerative potential of transplanted human bone marrow (BM) cells purified by high aldehyde dehydrogenase (ALDHhi) activity, a progenitor cell function conserved between several lineages. BM ALDHhi cells were enriched for myelo-erythroid progenitors that produced multipotent hematopoietic reconstitution after transplantation and contained nonhematopoietic precursors that established colonies in mesenchymal-stromal and endothelial culture conditions. The regenerative capacity of human ALDHhi cells was assessed by intravenous transplantation into immune-deficient mice with limb ischemia induced by femoral artery ligation/transection. Compared with recipients injected with unpurified nucleated cells containing the equivalent of 2- to 4-fold more ALDHhi cells, mice transplanted with purified ALDHhi cells showed augmented recovery of perfusion and increased blood vessel density in ischemic limbs. ALDHhi cells transiently recruited to ischemic regions but did not significantly integrate into ischemic tissue, suggesting that transient ALDHhi cell engraftment stimulated endogenous revascularization. Thus, human BM ALDHhi cells represent a progenitor-enriched population of several cell lineages that improves perfusion in ischemic limbs after transplantation. These clinically relevant cells may prove useful in the treatment of critical ischemia in humans. PMID:19324906

  9. Structural and functional comparison of two human liver dihydrodiol dehydrogenases associated with 3 alpha-hydroxysteroid dehydrogenase activity.

    PubMed Central

    Deyashiki, Y; Taniguchi, H; Amano, T; Nakayama, T; Hara, A; Sawada, H

    1992-01-01

    Two monomeric dihydrodiol dehydrogenases with pI values of 5.4 and 7.6 were co-purified with androsterone dehydrogenase activity to homogeneity from human liver. The two enzymes differed from each other on peptide mapping and in their heat-stabilities; with respect to the latter the dihydrodiol dehydrogenase and 3 alpha-hydroxysteroid dehydrogenase activities of the respective enzymes were similarly inactivated. The pI 5.4 enzyme was equally active towards trans- and cis-benzene dihydrodiols, and towards (S)- and (R)-forms of indan-1-ol and 1,2,3,4-tetrahydronaphth-1-ol and oxidized the 3 alpha-hydroxy group of C19-, C21- and C24-steroids, whereas the pI 7.6 enzyme showed high specificity for trans-benzene dihydrodiol, (S)-forms of the alicyclic alcohols and C19- and C21-steroids. Although the two enzymes reduced various xenobiotic carbonyl compounds and the 3-oxo group of C19- and C21-steroids, and were A-specific in the hydrogen transfer from NADPH, only the pI 5.4 enzyme showed reductase activity towards 7 alpha-hydroxy-5 beta-cholestan-3-one and dehydrolithocholic acid. The affinity of the two enzymes for the steroidal substrates was higher than that for the xenobiotic substrates. The two enzymes also showed different susceptibilities to the inhibition by anti-inflammatory drugs and bile acids. Whereas the pI-5.4 enzyme was highly sensitive to anti-inflammatory steroids, showing mixed-type inhibitions with respect to indan-1-ol and androsterone, the pI 7.6 enzyme was inhibited more potently by non-steroidal anti-inflammatory drugs and bile acids than by the steroidal drugs, and the inhibitions were all competitive. These structural and functional differences suggest that the two enzymes are 3 alpha-hydroxysteroid dehydrogenase isoenzymes. Images Fig. 2. PMID:1554355

  10. Enzymatic characterization of a novel bovine liver dihydrodiol dehydrogenase--reaction mechanism and bile acid dehydrogenase activity.

    PubMed

    Nanjo, H; Adachi, H; Morihana, S; Mizoguchi, T; Nishihara, T; Terada, T

    1995-05-11

    Bovine liver cytosolic dihydrodiol dehydrogenase (DD3) has been characterized by its unique dihydrodiol dehydrogenase activity for trans-benzenedihydrodiol (trans-1,2-dihydrobenzene-1,2-diol) with the highest affinity and the greatest velocity among three multiple forms of dihydrodiol dehydrogenases (DD1-DD3). It is the first time that DD3 has shown a significant dehydrogenase activity for (S)-(+)-1-indanol with low Km value (0.33 +/- 0.022 mM) and high K(cat) value (25 +/- 0.79 min-1). The investigation of the product inhibition of (S)-(+)-1-indanol with NADP+ versus 1-indanone and NADPH clearly showed that the enzymatic reaction of DD3 may follow a typical ordered Bi Bi mechanism similar to many aldo/keto reductases. Additionally, DD3 was shown to catalyze the dehydrogenation of bile acids (lithocholic acid, taurolithocholic acid and taurochenodeoxycholic acid) having no 12-hydroxy groups with low Km values (17 +/- 0.65, 33 +/- 1.9 and 890 +/- 73 microM, respectively). In contrast, DD1, 3 alpha-hydroxysteroid dehydrogenase, shows a broad substrate specificity for many bile acids with higher affinity than those of DD3. Competitive inhibition of DD3 with androsterone against dehydrogenase activity for (S)-(+)-1-indanol, trans-benzenedihydrodiol or lithocholic acid suggests that these three substrates bind to the same substrate binding site of DD3, different from the case of human liver bile acid binder/dihydrodiol dehydrogenase (Takikawa, H., Stolz, A., Sugiyama, Y., Yoshida, H., Yamamoto, M. and Kaplowitz, N. (1990) J. Biol. Chem. 265, 2132-2136). Considering the reaction mechanism, DD3 may also play an important role in bile acids metabolism as well as the detoxication of aromatic hydrocarbons.

  11. Acute cardiopulmonary toxicity of inhaled aldehydes: role of TRPA1

    PubMed Central

    Conklin, Daniel J.

    2016-01-01

    Inhalation of high-level volatile aldehydes, as present in smoke from wildfires and in tobacco smoke, is associated with both acute and chronic cardiopulmonary morbidity and mortality, but the underlying mechanisms are unclear. The transient receptor potential ankyrin 1 (TRPA1) protein forms a cation channel (irritant receptor) that mediates tobacco smoke–induced airway and lung injury, yet the role of TRPA1 in the cardiovascular toxicity of aldehyde exposure is unclear. Physiologically, airway-located TRPA1 activation triggers an irritant response (e.g., coughing and “respiratory braking”) that alters the rate and depth of breathing to reduce exposure. Acrolein (2-propenal), a volatile, unsaturated aldehyde, activates TRPA1. Acrolein was used as a chemical weapon in World War I and is present at high levels in wildfires and tobacco smoke. Acrolein is thought to contribute to pulmonary and cardiovascular injury caused by tobacco smoke exposure, although the role of TRPA1 in cardiovascular toxicity is unclear. This mini-review addresses this gap in our knowledge by exploring literature and recent data indicating a connection between TRPA1 and cardiovascular as well as pulmonary injury due to inhaled aldehydes. PMID:27152448

  12. In vivo Post-Cardiac Arrest Myocardial Dysfunction is Supported by CaMKII-Mediated Calcium Long-Term Potentiation and Mitigated by Alda-1, an Agonist of Aldehyde Dehydrogenase Type 2

    PubMed Central

    Downey, Peter; Zalewski, Adrian; Rubio, Gabriel R.; Liu, Jing; Homburger, Julian R.; Grunwald, Zachary; Qi, Wei; Bollensdorff, Christian; Thanaporn, Porama; Ali, Ayyaz; Riemer, Kirk; Kohl, Peter; Mochly-Rosen, Daria; Gerstenfeld, Edward; Large, Stephen; Ali, Ziad; Ashley, Euan

    2016-01-01

    Background Survival after sudden cardiac arrest is limited by post-arrest myocardial dysfunction but understanding of this phenomenon is constrained by lack of data from a physiological model of disease. In this study, we established an in vivo model of cardiac arrest and resuscitation, characterized the biology of the associated myocardial dysfunction, and tested novel therapeutic strategies. Methods We developed rodent models of in vivo post-arrest myocardial dysfunction using extra-corporeal membrane oxygenation (ECMO) resuscitation followed by invasive hemodynamics measurement. In post-arrest isolated cardiomyocytes, we assessed mechanical load and Ca2+ induced Ca2+ release (CICR) simultaneously using the micro-carbon-fiber technique and observed reduced function and myofilament calcium sensitivity. We used a novel-designed fiber optic catheter imaging system, and a genetically encoded calcium sensor GCaMP6f, to image CICR in vivo. Results We found potentiation of CICR in isolated cells from this ECMO model and also in cells isolated from an ischemia-reperfusion Langendorff model perfused with oxygenated blood from an arrested animal, but not when reperfused in saline. We established that CICR potentiation begins in vivo. The augmented CICR observed post-arrest was mediated by the activation of Ca2+/calmodulin kinase II (CaMKII). Increased phosphorylation of CaMKII, phospholamban and ryanodine receptor 2 (RyR2) was detected in the post-arrest period. Exogenous adrenergic activation in vivo recapitulated Ca2+ potentiation but was associated with lesser CaMKII activation. Since oxidative stress and aldehydic adduct formation were high post arrest, we tested a small molecule activator of aldehyde dehydrogenase type 2, Alda-1, which reduced oxidative stress, restored calcium and CaMKII homeostasis, and improved cardiac function and post-arrest outcome in vivo. Conclusions Cardiac arrest and reperfusion lead to CaMKII activation and calcium long-term potentiation

  13. Isocitrate dehydrogenase 1 and 2 mutations in cholangiocarcinoma.

    PubMed

    Kipp, Benjamin R; Voss, Jesse S; Kerr, Sarah E; Barr Fritcher, Emily G; Graham, Rondell P; Zhang, Lizhi; Highsmith, W Edward; Zhang, Jun; Roberts, Lewis R; Gores, Gregory J; Halling, Kevin C

    2012-10-01

    Somatic mutations in isocitrate dehydrogenase 1 and 2 genes are common in gliomas and help stratify patients with brain cancer into histologic and molecular subtypes. However, these mutations are considered rare in other solid tumors. The aims of this study were to determine the frequency of isocitrate dehydrogenase 1 and 2 mutations in cholangiocarcinoma and to assess histopathologic differences between specimens with and without an isocitrate dehydrogenase mutation. We sequenced 94 formalin-fixed, paraffin-embedded cholangiocarcinoma (67 intrahepatic and 27 extrahepatic) assessing for isocitrate dehydrogenase 1 (codon 132) and isocitrate dehydrogenase 2 (codons 140 and 172) mutations. Multiple histopathologic characteristics were also evaluated and compared with isocitrate dehydrogenase 1/2 mutation status. Of the 94 evaluated specimens, 21 (22%) had a mutation including 14 isocitrate dehydrogenase 1 and 7 isocitrate dehydrogenase 2 mutations. Isocitrate dehydrogenase mutations were more frequently observed in intrahepatic cholangiocarcinoma than in extrahepatic cholangiocarcinoma (28% versus 7%, respectively; P = .030). The 14 isocitrate dehydrogenase 1 mutations were R132C (n = 9), R132S (n = 2), R132G (n = 2), and R132L (n = 1). The 7 isocitrate dehydrogenase 2 mutations were R172K (n = 5), R172M (n = 1), and R172G (n = 1). Isocitrate dehydrogenase mutations were more frequently observed in tumors with clear cell change (P < .001) and poorly differentiated histology (P = .012). The results of this study show for the first time that isocitrate dehydrogenase 1 and 2 genes are mutated in cholangiocarcinoma. The results of this study are encouraging because it identifies a new potential target for genotype-directed therapeutic trials and may represent a potential biomarker for earlier detection of cholangiocarcinoma in a subset of cases. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Charged tag founded in N-(1-chloroalkyl)pyridinium quaternization for quantification of fatty aldehydes.

    PubMed

    Cao, Yanjing; Guan, Qing; Sun, Tuanqi; Qi, Wanshu; Guo, Yinlong

    2016-09-21

    N-(1-chloroalkyl)pyridinium quaternization was developed for the derivatization of fatty aldehydes. Differing from common pre-charged reagents, non-charged pyridine and thionyl chloride were designed to add permanently charged tag on aldehydes. Pyridine was far less competitive than charged derivatives in ionization. Thionyl chloride in excess was quenched by deionized water, converting into less residual sulfur dioxide bubbles. Thus solutions could be tested directly by mass spectrometry without further post-treatments. Pyridine-d5 labeled fatty aldehydes were prepared as internal standards. Mixed derivatives were then analyzed by high performance liquid chromatography coupled to positive electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Analytical parameters including reaction yield, stability, precision, linearity, and detection limits (LODs < 0.3 pg mL(-1)) were carefully validated. This method facilitated the analysis low content (ng mL(-1)) levels of free aliphatic aldehydes (C6C18) in human thyroid carcinoma and para-carcinoma tissue with a simple pretreatment procedure. Content of long chain nonvolatile aldehydes (C10C18) remarkably increased in thyroid carcinoma tissues (p < 0.05). Copyright © 2016. Published by Elsevier B.V.

  15. A Simple One-pot Conversion of Aldehydes and Ketones to Enals

    PubMed Central

    Valenta, Petr; Drucker, Natalie A.; Bode, Jeffrey W.; Walsh, Patrick J.

    2009-01-01

    A simple and efficient method to convert aldehydes into α,β-unsaturated aldehydes with a two-carbon homologation is presented. Hydroboration of ethoxy acetylene with BH3•SMe2 generates tris(ethoxyvinyl) borane. Transmetallation with diethylzinc, addition to aldehydes or ketones, and acidic workup affords enals. When the addition is quenched with anilinium hydrochloride, 1,2-dithioglycol, or acetic anhydride the unsaturated imine, dithiolane, or 1,1-diacetate is isolated in high yield. These transformations can be performed in a one-pot procedure. PMID:19419211

  16. Importance of inverse correlation between ALDH3A1 and PPARγ in tumor cells and tissue regeneration.

    PubMed

    Oraldi, M; Saracino, S; Maggiora, M; Chiaravalloti, A; Buemi, C; Martinasso, G; Paiuzzi, E; Thompson, D; Vasiliou, V; Canuto, R A

    2011-05-30

    Aldehyde dehydrogenase (ALDH) enzymes are involved in maintaining cellular homeostasis by metabolizing both endogenous and exogenous reactive aldehydes. They modulate several cell functions including proliferation, differentiation, survival as well as cellular response to oxidative stress. We previously reported that ALDH3A1 expression is inversely correlated with the activation of PPARs (Peroxisome Proliferators-Activated Receptors), a category of orphan nuclear hormone receptors, in both rat and human cells. PPARγ is involved in cell proliferation. In this study, we have used PPARγ transfection and inhibition to examine the relationship between ALDH3A1 and PPARγ and their role as regulators of cell proliferation. Induction of PPARγ in A549 and NCTC 2544 cells by transfection caused a decrease in ALDH3A1 and inhibition of cell proliferation, a result we obtained previously using ligands that induce PPARγ. A reduction of PPARγ expression using siRNA increased ALDH3A1 expression and cell proliferation. In cells induced to proliferate in a model of tissue regeneration, ALDH3A1 expression increased during the period of proliferation, whereas PPARγ expression decreased. In conclusion, through modulation of PPARγ or ALDH3A1, it may be possible to reduce cell proliferation in tumor cells or stimulate cell proliferation in normal cells during tissue regeneration. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. Geraniol and Geranial Dehydrogenases Induced in Anaerobic Monoterpene Degradation by Castellaniella defragrans

    PubMed Central

    Lüddeke, Frauke; Wülfing, Annika; Timke, Markus; Germer, Frauke; Weber, Johanna; Dikfidan, Aytac; Rahnfeld, Tobias; Linder, Dietmar; Meyerdierks, Anke

    2012-01-01

    Castellaniella defragrans is a Betaproteobacterium capable of coupling the oxidation of monoterpenes with denitrification. Geraniol dehydrogenase (GeDH) activity was induced during growth with limonene in comparison to growth with acetate. The N-terminal sequence of the purified enzyme directed the cloning of the corresponding open reading frame (ORF), the first bacterial gene for a GeDH (geoA, for geraniol oxidation pathway). The C. defragrans geraniol dehydrogenase is a homodimeric enzyme that affiliates with the zinc-containing benzyl alcohol dehydrogenases in the superfamily of medium-chain-length dehydrogenases/reductases (MDR). The purified enzyme most efficiently catalyzes the oxidation of perillyl alcohol (kcat/Km = 2.02 × 106 M−1 s−1), followed by geraniol (kcat/Km = 1.57 × 106 M−1 s−1). Apparent Km values of <10 μM are consistent with an in vivo toxicity of geraniol above 5 μM. In the genetic vicinity of geoA is a putative aldehyde dehydrogenase that was named geoB and identified as a highly abundant protein during growth with phellandrene. Extracts of Escherichia coli expressing geoB demonstrated in vitro a geranial dehydrogenase (GaDH) activity. GaDH activity was independent of coenzyme A. The irreversible formation of geranic acid allows for a metabolic flux from β-myrcene via linalool, geraniol, and geranial to geranic acid. PMID:22286981

  18. Geraniol and geranial dehydrogenases induced in anaerobic monoterpene degradation by Castellaniella defragrans.

    PubMed

    Lüddeke, Frauke; Wülfing, Annika; Timke, Markus; Germer, Frauke; Weber, Johanna; Dikfidan, Aytac; Rahnfeld, Tobias; Linder, Dietmar; Meyerdierks, Anke; Harder, Jens

    2012-04-01

    Castellaniella defragrans is a Betaproteobacterium capable of coupling the oxidation of monoterpenes with denitrification. Geraniol dehydrogenase (GeDH) activity was induced during growth with limonene in comparison to growth with acetate. The N-terminal sequence of the purified enzyme directed the cloning of the corresponding open reading frame (ORF), the first bacterial gene for a GeDH (geoA, for geraniol oxidation pathway). The C. defragrans geraniol dehydrogenase is a homodimeric enzyme that affiliates with the zinc-containing benzyl alcohol dehydrogenases in the superfamily of medium-chain-length dehydrogenases/reductases (MDR). The purified enzyme most efficiently catalyzes the oxidation of perillyl alcohol (k(cat)/K(m) = 2.02 × 10(6) M(-1) s(-1)), followed by geraniol (k(cat)/K(m) = 1.57 × 10(6) M(-1) s(-1)). Apparent K(m) values of <10 μM are consistent with an in vivo toxicity of geraniol above 5 μM. In the genetic vicinity of geoA is a putative aldehyde dehydrogenase that was named geoB and identified as a highly abundant protein during growth with phellandrene. Extracts of Escherichia coli expressing geoB demonstrated in vitro a geranial dehydrogenase (GaDH) activity. GaDH activity was independent of coenzyme A. The irreversible formation of geranic acid allows for a metabolic flux from β-myrcene via linalool, geraniol, and geranial to geranic acid.

  19. Purification, crystallization and preliminary crystallographic study of a recombinant plant aminoaldehyde dehydrogenase from Pisum sativum

    PubMed Central

    Tylichová, Martina; Briozzo, Pierre; Kopečný, David; Ferrero, Julien; Moréra, Solange; Joly, Nathalie; Snégaroff, Jacques; Šebela, Marek

    2008-01-01

    Aminoaldehydes are products of polyamine degradation and are known to be reactive metabolites that are toxic to living cells at high concentrations. These compounds are catabolized by aminoaldehyde dehydrogenases, which are enzymes that contain a nicotinamide adenine dinucleotide coenzyme. Amino­aldehyde dehydrogenase from Pisum sativum was overexpressed in Escherichia coli, purified and crystallized using the hanging-drop method. A complete data set was collected to 2.8 Å resolution at 100 K. Crystals belong to the monoclinic space group P21, with unit-cell parameters a = 86.4, b = 216.6, c = 205.4 Å, β = 98.1°. Molecular replacement was performed and led to the identification of six dimers per asymmetric unit. PMID:18259056

  20. Antisense RNA Downregulation of Coenzyme A Transferase Combined with Alcohol-Aldehyde Dehydrogenase Overexpression Leads to Predominantly Alcohologenic Clostridium acetobutylicum Fermentations

    PubMed Central

    Tummala, Seshu B.; Junne, Stefan G.; Papoutsakis, Eleftherios T.

    2003-01-01

    Plasmid pAADB1 for the overexpression of the alcohol-aldehyde dehydrogenase (aad) gene and downregulation of the coenzyme A transferase (CoAT) using antisense RNA (asRNA) against ctfB (the second CoAT gene on the polycistronic aad-ctfA-ctfB message) was used in order to increase the butanol/acetone ratio of Clostridium acetobutylicum ATCC 824 fermentations. Acetone and butanol levels were drastically reduced in 824(pCTFB1AS) (expresses only an asRNA against ctfB) compared to 824(pSOS95del) (plasmid control). Compared to strain 824(pCTFB1AS), 824(pAADB1) fermentations exhibited two profound differences. First, butanol levels were ca. 2.8-fold higher in 824(pAADB1) and restored back to plasmid control levels, thus supporting the hypothesis that asRNA downregulation of ctfB leads to degradation of the whole aad-ctfA-ctfB transcript. Second, ethanol titers in 824(pAADB1) were ca. 23-fold higher and the highest (ca. 200 mM) ever reported in C. acetobutylicum. Western blot analysis confirmed that CoAT was downregulated in 824(pAADB1) at nearly the same levels as in strain 824(pCTFB1AS). Butyrate depletion in 824(pAADB1) fermentations suggested that butyryl-CoA was limiting butanol production in 824(pAADB1). This was confirmed by exogenously adding butyric acid to 824(pAADB1) fermentations to increase the butanol/ethanol ratio. DNA microarray analysis showed that aad overexpression profoundly affects the large-scale transcriptional program of the cells. Several classes of genes were differentially expressed [strain 824(pAADB1) versus strain 824(pCTFB1AS)], including genes of the stress response, sporulation, and chemotaxis. The expression patterns of the CoAT genes (ctfA and ctfB) and aad were consistent with the overexpression of aad and asRNA downregulation of ctfB. PMID:12775702

  1. Antisense RNA downregulation of coenzyme A transferase combined with alcohol-aldehyde dehydrogenase overexpression leads to predominantly alcohologenic Clostridium acetobutylicum fermentations.

    PubMed

    Tummala, Seshu B; Junne, Stefan G; Papoutsakis, Eleftherios T

    2003-06-01

    Plasmid pAADB1 for the overexpression of the alcohol-aldehyde dehydrogenase (aad) gene and downregulation of the coenzyme A transferase (CoAT) using antisense RNA (asRNA) against ctfB (the second CoAT gene on the polycistronic aad-ctfA-ctfB message) was used in order to increase the butanol/acetone ratio of Clostridium acetobutylicum ATCC 824 fermentations. Acetone and butanol levels were drastically reduced in 824(pCTFB1AS) (expresses only an asRNA against ctfB) compared to 824(pSOS95del) (plasmid control). Compared to strain 824(pCTFB1AS), 824(pAADB1) fermentations exhibited two profound differences. First, butanol levels were ca. 2.8-fold higher in 824(pAADB1) and restored back to plasmid control levels, thus supporting the hypothesis that asRNA downregulation of ctfB leads to degradation of the whole aad-ctfA-ctfB transcript. Second, ethanol titers in 824(pAADB1) were ca. 23-fold higher and the highest (ca. 200 mM) ever reported in C. acetobutylicum. Western blot analysis confirmed that CoAT was downregulated in 824(pAADB1) at nearly the same levels as in strain 824(pCTFB1AS). Butyrate depletion in 824(pAADB1) fermentations suggested that butyryl-CoA was limiting butanol production in 824(pAADB1). This was confirmed by exogenously adding butyric acid to 824(pAADB1) fermentations to increase the butanol/ethanol ratio. DNA microarray analysis showed that aad overexpression profoundly affects the large-scale transcriptional program of the cells. Several classes of genes were differentially expressed [strain 824(pAADB1) versus strain 824(pCTFB1AS)], including genes of the stress response, sporulation, and chemotaxis. The expression patterns of the CoAT genes (ctfA and ctfB) and aad were consistent with the overexpression of aad and asRNA downregulation of ctfB.

  2. Structural and Functional Modifications of Corneal Crystallin ALDH3A1 by UVB Light

    PubMed Central

    Estey, Tia; Chen, Ying; Carpenter, John F.; Vasiliou, Vasilis

    2010-01-01

    As one of the most abundantly expressed proteins in the mammalian corneal epithelium, aldehyde dehydrogenase 3A1 (ALDH3A1) plays critical and multifaceted roles in protecting the cornea from oxidative stress. Recent studies have demonstrated that one protective mechanism of ALDH3A1 is the direct absorption of UV-energy, which reduces damage to other corneal proteins such as glucose-6-phosphate dehydrogenase through a competition mechanism. UV-exposure, however, leads to the inactivation of ALDH3A1 in such cases. In the current study, we demonstrate that UV-light caused soluble, non-native aggregation of ALDH3A1 due to both covalent and non-covalent interactions, and that the formation of the aggregates was responsible for the loss of ALDH3A1 enzymatic activity. Spectroscopic studies revealed that as a result of aggregation, the secondary and tertiary structure of ALDH3A1 were perturbed. LysC peptide mapping using MALDI-TOF mass spectrometry shows that UV-induced damage to ALDH3A1 also includes chemical modifications to Trp, Met, and Cys residues. Surprisingly, the conserved active site Cys of ALDH3A1 does not appear to be affected by UV-exposure; this residue remained intact after exposure to UV-light that rendered the enzyme completely inactive. Collectively, our data suggest that the UV-induced inactivation of ALDH3A1 is a result of non-native aggregation and associated structural changes rather than specific damage to the active site Cys. PMID:21203538

  3. Aldehyde dehydrogenase inhibition combined with phenformin treatment reversed NSCLC through ATP depletion.

    PubMed

    Kang, Joon Hee; Lee, Seon-Hyeong; Lee, Jae-Seon; Nam, Boas; Seong, Tae Wha; Son, Jaekyoung; Jang, Hyonchol; Hong, Kyeong Man; Lee, Cheolju; Kim, Soo-Youl

    2016-08-02

    Among ALDH isoforms, ALDH1L1 in the folate pathway showed highly increased expression in non-small-cell lung cancer cells (NSCLC). Based on the basic mechanism of ALDH converting aldehyde to carboxylic acid with by-product NADH, we suggested that ALDH1L1 may contribute to ATP production using NADH through oxidative phosphorylation. ALDH1L1 knockdown reduced ATP production by up to 60% concomitantly with decrease of NADH in NSCLC. ALDH inhibitor, gossypol, also reduced ATP production in a dose dependent manner together with decrease of NADH level in NSCLC. A combination treatment of gossypol with phenformin, mitochondrial complex I inhibitor, synergized ATP depletion, which efficiently induced cell death. Pre-clinical xenograft model using human NSCLC demonstrated a remarkable therapeutic response to the combined treatment of gossypol and phenformin.

  4. Implication of an Aldehyde Dehydrogenase Gene and a Phosphinothricin N-Acetyltransferase Gene in the Diversity of Pseudomonas cichorii Virulence

    PubMed Central

    Tanaka, Masayuki; Wali, Ullah Md; Nakayashiki, Hitoshi; Fukuda, Tatsuya; Mizumoto, Hiroyuki; Ohnishi, Kouhei; Kiba, Akinori; Hikichi, Yasufumi

    2011-01-01

    Pseudomonas cichorii harbors the hrp genes. hrp-mutants lose their virulence on eggplant but not on lettuce. A phosphinothricin N-acetyltransferase gene (pat) is located between hrpL and an aldehyde dehydrogenase gene (aldH) in the genome of P. cichorii. Comparison of nucleotide sequences and composition of the genes among pseudomonads suggests a common ancestor of hrp and pat between P. cichorii strains and P. viridiflava strains harboring the single hrp pathogenicity island. In contrast, phylogenetic diversification of aldH corresponded to species diversification amongst pseudomonads. In this study, the involvement of aldH and pat in P. cichorii virulence was analyzed. An aldH-deleted mutant (ΔaldH) and a pat-deleted mutant (Δpat) lost their virulence on eggplant but not on lettuce. P. cichorii expressed both genes in eggplant leaves, independent of HrpL, the transcriptional activator for the hrp. Inoculation into Asteraceae species susceptible to P. cichorii showed that the involvement of hrp, pat and aldH in P. cichorii virulence is independent of each other and has no relationship with the phylogeny of Asteraceae species based on the nucleotide sequences of ndhF and rbcL. It is thus thought that not only the hrp genes but also pat and aldH are implicated in the diversity of P. cichorii virulence on susceptible host plant species. PMID:24704843

  5. Development of a pair of differential H/D isotope-coded derivatization reagents d(0)/d(3)-4-(1-methyl-1H-phenanthro[9,10-d]imidazol-2-yl)phenlamine and its application for determination of aldehydes in selected aquatic products by liquid chromatography-tandem mass spectrometry.

    PubMed

    Sun, Zhiwei; Wang, Xiaoxiang; Cai, Yiping; Fu, Junqing; You, Jinmao

    2014-03-01

    A new pair of derivatization reagents, d0-4-(1-methyl-1H-phenanthro[9,10-d]imidazol-2-yl)phenlamine (d0-MPIA) and d3-4-(1-methyl-1H-phenanthro[9,10-d]imidazol-2-yl)phenlamine (d3-MPIA) have been designed and synthesized. It was successfully used to label aliphatic aldehydes and the aldehyde derivatives were analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The new isotope-coded reagents could easily label aldehydes under acidic conditions in the presence of NaCNBH3. The target derivatives exhibited intense [M+H](+) and regular product ions with electrospray ionization source in positive mode. The d0/d3-MPIA-aldehydes were monitored by the transitions of [M+H](+)→m/z 322 and [M+H](+)→m/z 165, and the obtained detection limits were in the range of 0.18-15.9 pg/mL at signal to noise ratio of 3. The global isotope internal standard technology was employed for quantification analysis with d3-MPIA-aldehyde as internal standard for corresponding d0-MPIA-aldehyde. Excellent linear responses for relative quantification were observed in the range of 1/10-10/1 with coefficients >0.998. The developed method has been applied to the quantification of aliphatic aldehydes in selected aquatic products with RSD<3.6% and recoveries >85.2%. © 2013 Elsevier B.V. All rights reserved.

  6. Facile synthesis of highly substituted 3-aminofurans from thiazolium salts, aldehydes, and dimethyl acetylenedicarboxylate.

    PubMed

    Ma, Cheng; Ding, Hanfeng; Wu, Guangming; Yang, Yewei

    2005-10-28

    [reaction: see text] A facile preparation of 3-aminofuran derivatives via multicomponent reactions of thiazole carbenes, aldehydes, and dimethyl acetylenedicarboxylate (DMAD) is reported. In this process, the thiazole carbenes, generated in situ from thiazolium salts, reacted with aldehydes and DMAD at -78 to 0 degree C in CH(2)Cl(2) to afford the substituted furans in moderate to good yields. Eight substituted thiazolium salts were employed as carbene precursors in the reaction. Besides aryl aldehydes, alpha,beta-unsaturated aldehydes, aliphatic aldehydes, and arenedial were also investigated and found to be applicable to this reaction.

  7. Ziram inhibits rat neurosteroidogenic 5α-reductase 1 and 3α-hydroxysteroid dehydrogenase.

    PubMed

    Su, Ying; Li, Huitao; Chen, Xiaomin; Wang, Yiyan; Li, Xiaoheng; Sun, Jianliang; Ge, Ren-Shan

    2018-01-01

    The neurotoxicity of ziram is largely unknown. In this study, we investigated the direct inhibitions of ziram on rat neurosteroid synthetic and metabolizing enzymes, 5α-reductase 1 (SRD5A1), 3α-hydroxysteroid dehydrogenase (AKR1C14), and retinol dehydrogenase 2 (RDH2). Rat SRD5A1, AKR1C14, and RDH2 were cloned and transiently expressed in COS1 cells, and the effects of ziram on these enzymes were measured. Ziram inhibited rat SRD5A1 and AKR1C14 with IC 50 values of 1.556 ± 0.078 and 1.017 ± 0.072 μM, respectively, when 1000 nM steroid substrates were used. Ziram weakly inhibited RDH2 at 100 μM, when androstanediol (1000 nM) was used. Ziram competitively inhibited SRD5A1 and non-competitively inhibited AKR1C14 when steroid substrates were used. Docking study showed that ziram bound to NADPH-binding pocket of AKR1C14. In conclusion, our results demonstrated that ziram inhibited SRD5A1 and AKR1C14 activities, thus possibly interfering with neurosteroid production in rats.

  8. ALDH1A3 Mutations Cause Recessive Anophthalmia and Microphthalmia

    PubMed Central

    Fares-Taie, Lucas; Gerber, Sylvie; Chassaing, Nicolas; Clayton-Smith, Jill; Hanein, Sylvain; Silva, Eduardo; Serey, Margaux; Serre, Valérie; Gérard, Xavier; Baumann, Clarisse; Plessis, Ghislaine; Demeer, Bénédicte; Brétillon, Lionel; Bole, Christine; Nitschke, Patrick; Munnich, Arnold; Lyonnet, Stanislas; Calvas, Patrick; Kaplan, Josseline; Ragge, Nicola; Rozet, Jean-Michel

    2013-01-01

    Anophthalmia and microphthalmia (A/M) are early-eye-development anomalies resulting in absent or small ocular globes, respectively. A/M anomalies occur in syndromic or nonsyndromic forms. They are genetically heterogeneous, some mutations in some genes being responsible for both anophthalmia and microphthalmia. Using a combination of homozygosity mapping, exome sequencing, and Sanger sequencing, we identified homozygosity for one splice-site and two missense mutations in the gene encoding the A3 isoform of the aldehyde dehydrogenase 1 (ALDH1A3) in three consanguineous families segregating A/M with occasional orbital cystic, neurological, and cardiac anomalies. ALDH1A3 is a key enzyme in the formation of a retinoic acid gradient along the dorso-ventral axis during early eye development. Transitory expression of mutant ALDH1A3 open reading frames showed that both missense mutations reduce the accumulation of the enzyme, potentially leading to altered retinoic acid synthesis. Although the role of retinoic acid signaling in eye development is well established, our findings provide genetic evidence of a direct link between retinoic-acid-synthesis dysfunction and early-eye-development anomalies in humans. PMID:23312594

  9. Aldehyde dehydrogenase inhibition combined with phenformin treatment reversed NSCLC through ATP depletion

    PubMed Central

    Lee, Jae-Seon; Nam, Boas; Seong, Tae Wha; Son, Jaekyoung; Jang, Hyonchol; Hong, Kyeong Man; Lee, Cheolju; Kim, Soo-Youl

    2016-01-01

    Among ALDH isoforms, ALDH1L1 in the folate pathway showed highly increased expression in non-small-cell lung cancer cells (NSCLC). Based on the basic mechanism of ALDH converting aldehyde to carboxylic acid with by-product NADH, we suggested that ALDH1L1 may contribute to ATP production using NADH through oxidative phosphorylation. ALDH1L1 knockdown reduced ATP production by up to 60% concomitantly with decrease of NADH in NSCLC. ALDH inhibitor, gossypol, also reduced ATP production in a dose dependent manner together with decrease of NADH level in NSCLC. A combination treatment of gossypol with phenformin, mitochondrial complex I inhibitor, synergized ATP depletion, which efficiently induced cell death. Pre-clinical xenograft model using human NSCLC demonstrated a remarkable therapeutic response to the combined treatment of gossypol and phenformin. PMID:27384481

  10. Cinnamic aldehyde: a survey of consumer patch-test sensitization.

    PubMed

    Danneman, P J; Booman, K A; Dorsky, J; Kohrman, K A; Rothenstein, A S; Sedlak, R I; Steltenkamp, R J; Thompson, G R

    1983-12-01

    The potential for cinnamic aldehyde, an important fragrance and flavour ingredient, to induce or to elicit delayed contact hypersensitivity reactions in man was evaluated by analysing patch-test data. Results of studies involving a total of 4117 patch tests on various consumer products and fragrance blends containing cinnamic aldehyde and on the material itself were collected from fragrance and formulator companies. The data indicate that cinnamic aldehyde contained in consumer products and fragrance blends at concentrations up to 6 X 10(-1)%, and patch-tested at concentrations up to 8 X 10(-3)%, has no detectable potential to induce hypersensitivity. Cinnamic aldehyde when tested alone induced a dose-related hypersensitivity response. According to published reports, cinnamic aldehyde elicited positive delayed hypersensitivity responses in dermatitic patients. However, results of the current survey show that when cinnamic aldehyde was tested alone or as part of a mixture in subjects in the general population, no pre-existing hypersensitivity reactions to the fragrance material were observed in any of the 4117 patch tests which constituted the survey. Cinnamic aldehyde at the concentrations contained in consumer products and fragrances, has a very low potential to induce hypersensitivity ('induced' reactions) or to elicit sensitization reactions ('elicited' reactions) in the general population.

  11. Role of aldehyde dehydrogenase in hypoxic vasodilator effects of nitrite in rats and humans

    PubMed Central

    Arif, Sayqa; Borgognone, Alessandra; Lin, Erica Lai-Sze; O'Sullivan, Aine G; Sharma, Vishal; Drury, Nigel E; Menon, Ashvini; Nightingale, Peter; Mascaro, Jorge; Bonser, Robert S; Horowitz, John D; Feelisch, Martin; Frenneaux, Michael P; Madhani, Melanie

    2015-01-01

    Background and Purpose Hypoxic conditions favour the reduction of nitrite to nitric oxide (NO) to elicit vasodilatation, but the mechanism(s) responsible for bioconversion remains ill defined. In the present study, we assess the role of aldehyde dehydrogenase 2 (ALDH2) in nitrite bioactivation under normoxia and hypoxia in the rat and human vasculature. Experimental Approach The role of ALDH2 in vascular responses to nitrite was studied using rat thoracic aorta and gluteal subcutaneous fat resistance vessels from patients with heart failure (HF; 16 patients) in vitro and by measurement of changes in forearm blood flow (FBF) during intra-arterial nitrite infusion (21 patients) in vivo. Specifically, we investigated the effects of (i) ALDH2 inhibition by cyanamide or propionaldehyde and the (ii) tolerance-independent inactivation of ALDH2 by glyceryl trinitrate (GTN) on the vasodilator activity of nitrite. In each setting, nitrite effects were measured via evaluation of the concentration–response relationship under normoxic and hypoxic conditions in the absence or presence of ALDH2 inhibitors. Key Results Both in rat aorta and human resistance vessels, dilatation to nitrite was diminished following ALDH2 inhibition, in particular under hypoxia. In humans there was a non-significant trend towards attenuation of nitrite-mediated increases in FBF. Conclusions and Implications In human and rat vascular tissue in vitro, hypoxic nitrite-mediated vasodilatation involves ALDH2. In patients with HF in vivo, the role of this enzyme in nitrite bioactivation is at the most, modest, suggesting the involvement of other more important mechanisms. PMID:25754766

  12. Apigenin inhibits rat neurosteroidogenic 5α-reductase 1 and 3α-hydroxysteroid dehydrogenase.

    PubMed

    Wu, Ying; Li, Lili; Zhou, Songyi; Shen, Qiuxia; Lin, Han; Zhu, Qiqi; Sun, Jianliang; Ge, Ren-Shan

    2017-11-01

    Apigenin, a common flavonoid, has extensive pharmacological activities. Apigenin inhibits some steroid biosynthetic enzymes, suggesting that it may block neurosteroid synthesis. Neurosteroids play many important roles in neurological functions. The objective of the present study is to investigate effects of apigenin on neurosteroidogenic enzymes, 5α-reductase 1 (SRD5A1), 3α-hydroxysteroid dehydrogenase (AKR1C9), and retinol dehydrogenase 2 (RoDH2), in rats. SRD5A1, AKR1C9, and RoDH2 were expressed in COS-1 cells and the effects of apigenin on these enzymes and modes of action were explored using radiolabeled substrates and thin-layer chromatographic separation coupled with radiometry. Apigenin inhibited SRD5A1, AKR1C9, and RoDH2 activities with IC 50 values of 100, 0.891 ± 0.065, and >100 μM, respectively. Apigenin competitively inhibited rat AKR1C9 when its substrate 5α-dihydrotestosterone was used and uncompetitively inhibited the enzyme when cofactor NADPH was used. In conclusion, apigenin is a potent inhibitor of rat AKR1C9, thereby controlling the rate of neurosteroid biosynthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Cloning, sequence, and disruption of the Saccharomyces diastaticus DAR1 gene encoding a glycerol-3-phosphate dehydrogenase.

    PubMed

    Wang, H T; Rahaim, P; Robbins, P; Yocum, R R

    1994-11-01

    The Saccharomyces diastaticus DAR1 gene was cloned by complementation in an Escherichia coli strain auxogrophic for glycerol-3-phosphate. DAR1 encodes an NADH-dependent dihydroxyacetone phosphate reductase (sn-glycerol-3-phosphate dehydrogenase [G3PDase; EC 1.1.1.8]) homologous to several other eukaryotic G3PDases. DAR1 is distinct from GUT2, which encodes a glucose-repressed mitochondrial G3PDase, but is identical to GPD1 from S. cerevisiae, a close relative of S. diastaticus. The level of DAR1-encoded G3PDase was increased about threefold in a medium of high osmolarity. Disruption of DAR1 in a haploid S. cerevisiae was not lethal but led to a decrease in cytoplasmic NADH-dependent G3PDase activity, an increase in osmotic sensitivity, and a 25% reduction in glycerol secretion from cells grown anaerobically on glucose.

  14. GLYCERALDEHYDE 3-PHOSPHATE DEHYDROGENASE-S, A SPERM-SPECIFIC GLYCOLYTIC ENZYME, IS REQUIRED FOR SPERM MOTILITY AND MALE FERTILITY

    EPA Science Inventory

    While glycolysis is highly conserved, it is remarkable that several novel isozymes in this central metabolic pathway are found in mammalian sperm. Glyceraldehyde 3-phosphate dehydrogenase-S (GAPDS) is the product of a mouse gene expressed only during spermatogenesis and, like it...

  15. Metabolism of MRX-I, a novel antibacterial oxazolidinone, in humans: the oxidative ring opening of 2,3-Dihydropyridin-4-one catalyzed by non-P450 enzymes.

    PubMed

    Meng, Jian; Zhong, Dafang; Li, Liang; Yuan, Zhengyu; Yuan, Hong; Xie, Cen; Zhou, Jialan; Li, Chen; Gordeev, Mikhail Fedorovich; Liu, Jinqian; Chen, Xiaoyan

    2015-05-01

    MRX-I is an analog of linezolid containing a 2,3-dihydropyridin-4-one (DHPO) ring rather than a morpholine ring. Our objectives were to characterize the major metabolic pathways of MRX-I in humans and clarify the mechanism underlying the oxidative ring opening of DHPO. After an oral dose of MRX-I (600 mg), nine metabolites were identified in humans. The principal metabolic pathway proposed involved the DHPO ring opening, generating the main metabolites in the plasma and urine: the hydroxyethyl amino propionic acid metabolite MRX445-1 and the carboxymethyl amino propionic acid metabolite MRX459. An in vitro phenotyping study demonstrated that multiple non-cytochrome P450 enzymes are involved in the formation of MRX445-1 and MRX459, including flavin-containing monooxygenase 5, short-chain dehydrogenase/reductase, aldehyde ketone reductase, and aldehyde dehydrogenase (ALDH). H2 (18)O experiments revealed that two (18)O atoms are incorporated into MRX445-1, one in the carboxyethyl group and the other in the hydroxyl group, and three (18)O atoms are incorporated into MRX459, two in the carboxymethyl group and one in the hydroxyl group. Based on these results, the mechanism proposed for the DHPO ring opening involves the metabolism of MRX-I via FMO5-mediated Baeyer-Villiger oxidation to an enol lactone, hydrolysis to an enol, and enol-aldehyde tautomerism to an aldehyde. The aldehyde is reduced by short-chain dehydrogenase/reductase, aldehyde ketone reductase, ALDH to MRX445-1, or oxidized by ALDH to MRX459. Our study suggests that few clinical adverse drug-drug interactions should be anticipated between MRX-I and cytochrome P450 inhibitors or inducers. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  16. Two-carbon homologation of aldehydes and ketones to α,β-unsaturated aldehydes.

    PubMed

    Petroski, Richard J; Vermillion, Karl; Cossé, Allard A

    2011-06-17

    Phosphonate reagents were developed for the two-carbon homologation of aldehydes or ketones to unbranched- or methyl-branched α,β-unsaturated aldehydes. The phosphonate reagents, diethyl methylformyl-2-phosphonate dimethylhydrazone and diethyl ethylformyl-2-phosphonate dimethylhydrazone, contained a protected aldehyde group instead of the usual ester group. A homologation cycle entailed condensation of the reagent with the starting aldehyde, followed by removal of the dimethylhydrazone protective group with a biphasic mixture of 1 M HCl and petroleum ether. This robust two-step process worked with a variety of aldehydes and ketones. Overall isolated yields of unsaturated aldehyde products ranged from 71% to 86% after the condensation and deprotection steps.

  17. Enantioselective ProPhenol-catalyzed addition of 1,3-diynes to aldehydes to generate synthetically versatile building blocks and diyne natural products.

    PubMed

    Trost, Barry M; Chan, Vincent S; Yamamoto, Daisuke

    2010-04-14

    A highly enantioselective method for the catalytic addition of terminal 1,3-diynes to aldehydes was developed using our dinuclear zinc ProPhenol (1) system. Furthermore, triphenylphosphine oxide was found to interact synergistically with the catalyst to substantially enhance the chiral recognition. The generality of this catalytic transformation was demonstrated with aryl, alpha,beta-unsaturated and saturated aldehydes, of which the latter were previously limited in alkynyl zinc additions. The chiral diynol products are also versatile building blocks that can be readily elaborated; this was illustrated through highly selective trans-hydrosilylations, which enabled the synthesis of a beta-hydroxyketone and enyne. Additionally, the development of this method allowed for the rapid total syntheses of several biologically important diynol-containing natural products.

  18. Complex inhibition of autophagy by mitochondrial aldehyde dehydrogenase shortens lifespan and exacerbates cardiac aging.

    PubMed

    Zhang, Yingmei; Wang, Cong; Zhou, Jingmin; Sun, Aijun; Hueckstaedt, Lindsay K; Ge, Junbo; Ren, Jun

    2017-08-01

    Autophagy, a conservative degradation process for long-lived and damaged proteins, participates in a cascade of biological processes including aging. A number of autophagy regulators have been identified. Here we demonstrated that mitochondrial aldehyde dehydrogenase (ALDH2), an enzyme with the most common single point mutation in humans, governs cardiac aging through regulation of autophagy. Myocardial mechanical and autophagy properties were examined in young (4months) and old (26-28months) wild-type (WT) and global ALDH2 transgenic mice. ALDH2 overexpression shortened lifespan by 7.7% without affecting aging-associated changes in plasma metabolic profiles. Myocardial function was compromised with aging associated with cardiac hypertrophy, the effects were accentuated by ALDH2. Aging overtly suppressed autophagy and compromised autophagy flux, the effects were exacerbated by ALDH2. Aging dampened phosphorylation of JNK, Bcl-2, IKKβ, AMPK and TSC2 while promoting phosphorylation of mTOR, the effects of which were exaggerated by ALDH2. Co-immunoprecipitation revealed increased dissociation between Bcl-2 and Beclin-1 (result of decreased Bcl-2 phosphorylation) in aging, the effect of which was exacerbated with ALDH2. Chronic treatment of the autophagy inducer rapamycin alleviated aging-induced cardiac dysfunction in both WT and ALDH2 mice. Moreover, activation of JNK and inhibition of either Bcl-2 or IKKβ overtly attenuated ALDH2 activation-induced accentuation of cardiomyocyte aging. Examination of the otherwise elderly individuals revealed a positive correlation between cardiac function/geometry and ALDH2 gene mutation. Taken together, our data revealed that ALDH2 enzyme may suppress myocardial autophagy possibly through a complex JNK-Bcl-2 and IKKβ-AMPK-dependent mechanism en route to accentuation of myocardial remodeling and contractile dysfunction in aging. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure

  19. Formation of Nitric Oxide by Aldehyde Dehydrogenase-2 Is Necessary and Sufficient for Vascular Bioactivation of Nitroglycerin.

    PubMed

    Opelt, Marissa; Eroglu, Emrah; Waldeck-Weiermair, Markus; Russwurm, Michael; Koesling, Doris; Malli, Roland; Graier, Wolfgang F; Fassett, John T; Schrammel, Astrid; Mayer, Bernd

    2016-11-11

    Aldehyde dehydrogenase-2 (ALDH2) catalyzes vascular bioactivation of the antianginal drug nitroglycerin (GTN), resulting in activation of soluble guanylate cyclase (sGC) and cGMP-mediated vasodilation. We have previously shown that a minor reaction of ALDH2-catalyzed GTN bioconversion, accounting for about 5% of the main clearance-based turnover yielding inorganic nitrite, results in direct NO formation and concluded that this minor pathway could provide the link between vascular GTN metabolism and activation of sGC. However, lack of detectable NO at therapeutically relevant GTN concentrations (≤1 μm) in vascular tissue called into question the biological significance of NO formation by purified ALDH2. We addressed this issue and used a novel, highly sensitive genetically encoded fluorescent NO probe (geNOp) to visualize intracellular NO formation at low GTN concentrations (≤1 μm) in cultured vascular smooth muscle cells (VSMC) expressing an ALDH2 mutant that reduces GTN to NO but lacks clearance-based GTN denitration activity. NO formation was compared with GTN-induced activation of sGC. The addition of 1 μm GTN to VSMC expressing either wild-type or C301S/C303S ALDH2 resulted in pronounced intracellular NO elevation, with maximal concentrations of 7 and 17 nm, respectively. Formation of GTN-derived NO correlated well with activation of purified sGC in VSMC lysates and cGMP accumulation in intact porcine aortic endothelial cells infected with wild-type or mutant ALDH2. Formation of NO and cGMP accumulation were inhibited by ALDH inhibitors chloral hydrate and daidzin. The present study demonstrates that ALDH2-catalyzed NO formation is necessary and sufficient for GTN bioactivation in VSMC. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Hangover symptoms in Asian Americans with variations in the aldehyde dehydrogenase (ALDH2) gene.

    PubMed

    Wall, T L; Horn, S M; Johnson, M L; Smith, T L; Carr, L G

    2000-01-01

    Hangovers are not experienced by all people and whether they contribute to the development of alcoholism is unclear. One population that might provide some insight into the role of hangover in the etiology of alcohol use disorders is that of individuals of Asian heritage. Certain Asians have lower rates of alcohol use and alcoholism, findings associated with a mutation in the aldehyde dehydrogenase (ALDH2) gene. Asians with ALDH2*2 alleles drink less and are less likely to be alcoholic than Asians without this mutation. Following alcohol ingestion, they exhibit more intense reactions to alcohol and generate higher levels of the metabolite acetaldehyde. This study evaluated hangover symptoms in Asian Americans with variations in the ALDH2 gene. Men and women of Chinese, Japanese and Korean heritage (N = 140) were asked about their drinking history and a blood sample was collected for genotyping at the ALDH2 locus. Subjects used a Likert-type scale to estimate their severity of hangover and completed a 13-item hangover scale assessing the frequency of hangover symptoms during the previous 6 months. With abstainers (n = 17) excluded and with the effects of gender and recent drinking history controlled, ALDH2 genotype accounted for a significant amount of additional variability in the estimated severity of hangover score with a similar, but nonsignificant, trend for a five-item subscale score derived from the hangover scale. These results suggest that Asian Americans with ALDH2*2 alleles may experience more severe hangovers that may contribute, in part, to protection against the development of excessive or problematic drinking in this population.

  1. Synthesis of highly substituted 2,3-dihydropyrimido[4,5-d]pyrimidin-4(1H)-ones from 4,6-dichloro-5-formylpyrimidine, amines and aldehydes.

    PubMed

    Xiang, Jinbao; Geng, Chao; Yi, Lang; Dang, Qun; Bai, Xu

    2011-11-01

    A practical strategy was developed for the preparation of highly substituted 2,3-dihydropyrimido[4,5-d]pyrimidin-4(1H)-ones from 4,6-dichloro-5-formylpyrimidine, primary amines, and aldehydes. The key step for this synthesis entails a cyclization reaction involving an intramolecular amide addition to an iminium intermediate formed in situ from 4-amino-pyrimidine-5-carboxamide 2 and aldehydes to form the pyrimido[4,5-d]pyrimidine core with a strategically placed 5-Cl group for further derivatization. The utility of this methodology was demonstrated through the preparation of a 27-membered library of representative 2,3-dihydropyrimido[4,5-d]pyrimidin-4(1H)-ones in moderate to good yields.

  2. Novel NAD+-Farnesal Dehydrogenase from Polygonum minus Leaves. Purification and Characterization of Enzyme in Juvenile Hormone III Biosynthetic Pathway in Plant

    PubMed Central

    Mohamed-Hussein, Zeti-Azura; Ng, Chyan Leong

    2016-01-01

    Juvenile Hormone III is of great concern due to negative effects on major developmental and reproductive maturation in insect pests. Thus, the elucidation of enzymes involved JH III biosynthetic pathway has become increasing important in recent years. One of the enzymes in the JH III biosynthetic pathway that remains to be isolated and characterized is farnesal dehydrogenase, an enzyme responsible to catalyze the oxidation of farnesal into farnesoic acid. A novel NAD+-farnesal dehydrogenase of Polygonum minus was purified (315-fold) to apparent homogeneity in five chromatographic steps. The purification procedures included Gigacap S-Toyopearl 650M, Gigacap Q-Toyopearl 650M, and AF-Blue Toyopearl 650ML, followed by TSK Gel G3000SW chromatographies. The enzyme, with isoelectric point of 6.6 is a monomeric enzyme with a molecular mass of 70 kDa. The enzyme was relatively active at 40°C, but was rapidly inactivated above 45°C. The optimal temperature and pH of the enzyme were found to be 35°C and 9.5, respectively. The enzyme activity was inhibited by sulfhydryl agent, chelating agent, and metal ion. The enzyme was highly specific for farnesal and NAD+. Other terpene aldehydes such as trans- cinnamaldehyde, citral and α- methyl cinnamaldehyde were also oxidized but in lower activity. The Km values for farnesal, citral, trans- cinnamaldehyde, α- methyl cinnamaldehyde and NAD+ were 0.13, 0.69, 0.86, 1.28 and 0.31 mM, respectively. The putative P. minus farnesal dehydrogenase that’s highly specific towards farnesal but not to aliphatic aldehydes substrates suggested that the enzyme is significantly different from other aldehyde dehydrogenases that have been reported. The MALDI-TOF/TOF-MS/MS spectrometry further identified two peptides that share similarity to those of previously reported aldehyde dehydrogenases. In conclusion, the P. minus farnesal dehydrogenase may represent a novel plant farnesal dehydrogenase that exhibits distinctive substrate specificity

  3. Cloning, sequence, and disruption of the Saccharomyces diastaticus DAR1 gene encoding a glycerol-3-phosphate dehydrogenase.

    PubMed Central

    Wang, H T; Rahaim, P; Robbins, P; Yocum, R R

    1994-01-01

    The Saccharomyces diastaticus DAR1 gene was cloned by complementation in an Escherichia coli strain auxogrophic for glycerol-3-phosphate. DAR1 encodes an NADH-dependent dihydroxyacetone phosphate reductase (sn-glycerol-3-phosphate dehydrogenase [G3PDase; EC 1.1.1.8]) homologous to several other eukaryotic G3PDases. DAR1 is distinct from GUT2, which encodes a glucose-repressed mitochondrial G3PDase, but is identical to GPD1 from S. cerevisiae, a close relative of S. diastaticus. The level of DAR1-encoded G3PDase was increased about threefold in a medium of high osmolarity. Disruption of DAR1 in a haploid S. cerevisiae was not lethal but led to a decrease in cytoplasmic NADH-dependent G3PDase activity, an increase in osmotic sensitivity, and a 25% reduction in glycerol secretion from cells grown anaerobically on glucose. PMID:7961476

  4. Birth of Archaeal Cells: Molecular Phylogenetic Analyses of G1P Dehydrogenase, G3P Dehydrogenases, and Glycerol Kinase Suggest Derived Features of Archaeal Membranes Having G1P Polar Lipids

    PubMed Central

    2016-01-01

    Bacteria and Eukarya have cell membranes with sn-glycerol-3-phosphate (G3P), whereas archaeal membranes contain sn-glycerol-1-phosphate (G1P). Determining the time at which cells with either G3P-lipid membranes or G1P-lipid membranes appeared is important for understanding the early evolution of terrestrial life. To clarify this issue, we reconstructed molecular phylogenetic trees of G1PDH (G1P dehydrogenase; EgsA/AraM) which is responsible for G1P synthesis and G3PDHs (G3P dehydrogenase; GpsA and GlpA/GlpD) and glycerol kinase (GlpK) which is responsible for G3P synthesis. Together with the distribution of these protein-encoding genes among archaeal and bacterial groups, our phylogenetic analyses suggested that GlpA/GlpD in the Commonote (the last universal common ancestor of all extant life with a cellular form, Commonote commonote) acquired EgsA (G1PDH) from the archaeal common ancestor (Commonote archaea) and acquired GpsA and GlpK from a bacterial common ancestor (Commonote bacteria). In our scenario based on this study, the Commonote probably possessed a G3P-lipid membrane synthesized enzymatically, after which the archaeal lineage acquired G1PDH followed by the replacement of a G3P-lipid membrane with a G1P-lipid membrane. PMID:27774041

  5. Two New Alleles of the abscisic aldehyde oxidase 3 Gene Reveal Its Role in Abscisic Acid Biosynthesis in Seeds1

    PubMed Central

    González-Guzmán, Miguel; Abia, David; Salinas, Julio; Serrano, Ramón; Rodríguez, Pedro L.

    2004-01-01

    The abscisic aldehyde oxidase 3 (AAO3) gene product of Arabidopsis catalyzes the final step in abscisic acid (ABA) biosynthesis. An aao3-1 mutant in a Landsberg erecta genetic background exhibited a wilty phenotype in rosette leaves, whereas seed dormancy was not affected (Seo et al., 2000a). Therefore, it was speculated that a different aldehyde oxidase would be the major contributor to ABA biosynthesis in seeds (Seo et al., 2000a). Through a screening based on germination under high-salt concentration, we isolated two mutants in a Columbia genetic background, initially named sre2-1 and sre2-2 (for salt resistant). Complementation tests with different ABA-deficient mutants indicated that sre2-1 and sre2-2 mutants were allelic to aao3-1, and therefore they were renamed as aao3-2 and aao3-3, respectively. Indeed, molecular characterization of the aao3-2 mutant revealed a T-DNA insertional mutation that abolished the transcription of AAO3 gene, while sequence analysis of AAO3 in aao3-3 mutant revealed a deletion of three nucleotides and several missense mutations. Physiological characterization of aao3-2 and aao3-3 mutants revealed a wilty phenotype and osmotolerance in germination assays. In contrast to aao3-1, both aao3-2 and aao3-3 mutants showed a reduced dormancy. Accordingly, ABA levels were reduced in dry seeds and rosette leaves of both aao3-2 and aao3-3. Taken together, these results indicate that AAO3 gene product plays a major role in seed ABA biosynthesis. PMID:15122034

  6. Degradation of glyceraldehyde-3-phosphate dehydrogenase triggered by 4-hydroxy-2-nonenal and 4-hydroxy-2-hexenal.

    PubMed

    Tsuchiya, Yukihiro; Yamaguchi, Mitsune; Chikuma, Toshiyuki; Hojo, Hiroshi

    2005-06-15

    Lipid peroxidation products such as 4-hydroxy-2-nonenal (HNE) may be responsible for various pathophysiological events under oxidative stress, since they injure cellular components such as proteins and DNA. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), which is a key enzyme of glycolysis and has been reported to be a multifunctional enzyme, is one of the enzymes inhibited by HNE. Previous studies showed that GAPDH is degraded when incubated with acetylleucine chloromethyl ketone (ALCK), resulting in the liberation of a 23-kDa fragment. In this study, we examined whether GAPDH incubated with HNE or other aldehydes of lipid peroxidation products are degraded similarly to that with ALCK. The U937 cell extract was incubated with these aldehydes at 37 degrees C and analyzed by Western blotting using anti-GAPDH antibodies. Incubation with HNE or 4-hydroxy-2-hexenal (HHE) decreased GAPDH activity and GAPDH protein level, and increased the 23-kDa fragment, in time- and dose-dependent manners, but that with other aldehydes did not. Gel filtration using the Superose 6 showed that the GAPDH-degrading activity was eluted in higher molecular fractions than proteasome activity. The enzyme activity was detected at the basic range of pH and inhibited by serine protease inhibitors, diisopropyl fluorophosphate and phenylmethylsulfonyl fluoride, but not by other protease inhibitors including a proteasome inhibitor, MG-132, and a tripeptidyl peptidase II (TPP II) inhibitor, AAF-CMK. These results suggest that GAPDH modified by HNE and HHE is degraded by a giant serine protease, releasing the 23-kDa fragment, not by proteasome or TPP II.

  7. Salt-induction of betaine aldehyde dehydrogenase mRNA, protein, and enzymatic activity in sugar beet. [Beta vulgaris L

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McCue, K.F.; Hanson, A.D.

    1991-05-01

    In Chenopodiaceae such as sugar beet (Beta vulgaris L.), glycine betaine (betaine) accumulates in response to drought or salinity stress and functions in the cytoplasm as a compatible osmolyte. The last enzyme in the biosynthetic pathway, betaine aldehyde dehydrogenase (BADH), increases as much as 4-fold in response to rising salinity in the external medium. This increase is accompanied by an increase in both protein and mRNA levels. The steady state increases in BADH were examined at a series of NaCl concentrations from 100 to 500 mM NaCl. BADH protein levels were examined by native PAGE, and by western blot analysismore » using antibodies raised against BADH purified from spinach. mRNA levels were examined by northern plot analysis of total RNA isolated from the leaves and hybridized with a sugar beet BADH cDNA clone. The time course for BADH mRNA induction was determined in a salt shock experiment utilizing 400 mM NaCl added to the external growth medium. Disappearance of BADH was examined in a salt relief experiment using plants step-wise salinized to 500 mM NaCl and then returned to 0 mM NaCl.« less

  8. Genetics Home Reference: 3-hydroxyacyl-CoA dehydrogenase deficiency

    MedlinePlus

    ... short chain 3-hydroxylacyl-CoA dehydrogenase deficiency Screening, Technology and Research in Genetics (STAR-G) Patient Support and Advocacy Resources (3 links) Children Living with Inherited Metabolic Diseases (CLIMB) FOD (Fatty ...

  9. Characterization of hamster NAD+-dependent 3(17)β-hydroxysteroid dehydrogenase belonging to the aldo-keto reductase 1C subfamily.

    PubMed

    Endo, Satoshi; Noda, Misato; Ikari, Akira; Tatematsu, Kenjiro; El-Kabbani, Ossama; Hara, Akira; Kitade, Yukio; Matsunaga, Toshiyuki

    2015-11-01

    The cDNAs for morphine 6-dehydrogenase (AKR1C34) and its homologous aldo-keto reductase (AKR1C35) were cloned from golden hamster liver, and their enzymatic properties and tissue distribution were compared. AKR1C34 and AKR1C35 similarly oxidized various xenobiotic alicyclic alcohols using NAD(+), but differed in their substrate specificity for hydroxysteroids and inhibitor sensitivity. While AKR1C34 showed 3α/17β/20α-hydroxysteroid dehydrogenase activities, AKR1C35 efficiently oxidized various 3β- and 17β-hydroxysteroids, including biologically active 3β-hydroxy-5α/β-dihydro-C19/C21-steroids, dehydroepiandrosterone and 17β-estradiol. AKR1C35 also differed from AKR1C34 in its high sensitivity to flavonoids, which inhibited competitively with respect to 17β-estradiol (Ki 0.11-0.69 μM). The mRNA for AKR1C35 was expressed liver-specific in male hamsters and ubiquitously in female hamsters, whereas the expression of the mRNA for AKR1C34 displayed opposite sexual dimorphism. Because AKR1C35 is the first 317Β-HYDROXYSTEROID DEHYDROGENASE IN THE AKR SUPERFAMILY: , we also investigated the molecular determinants for the 3β-hydroxysteroid dehydrogenase activity by replacement of Val54 and Cys310 in AKR1C35 with the corresponding residues in AKR1C34, Ala and Phe, respectively. The mutation of Val54Ala, but not Cys310Phe, significantly impaired this activity, suggesting that Val54 plays a critical role in recognition of the steroidal substrate. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  10. Expression and kinetic properties of a recombinant 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase isoenzyme of human liver.

    PubMed

    Deyashiki, Y; Tamada, Y; Miyabe, Y; Nakanishi, M; Matsuura, K; Hara, A

    1995-08-01

    Human liver cytosol contains multiple forms of 3 alpha-hydroxysteroid dehydrogenase and dihydrodiol dehydrogenase with hydroxysteroid dehydrogenase activity, and multiple cDNAs for the enzymes have been cloned from human liver cDNA libraries. To understand the relationship of the multiple enzyme froms to the genes, a cDNA, which has been reported to code for an isoenzyme of human liver 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase, was expressed in Escherichia coli. The recombinant enzyme showed structural and functional properties almost identical to those of the isoenzyme purified from human liver. In addition, the recombinant isoenzyme efficiently reduced 5 alpha-dihydrotestosterone and 5 beta-dihydrocortisone, the known substrates of human liver 3 alpha-hydroxysteroid dehydrogenase and chlordecone reductase previously purified, which suggests that these human liver enzymes are identical. Furthermore, the steady-state kinetic data for NADP(+)-linked (S)-1-indanol oxidation by the recombinant isoenzyme were consistent with a sequential ordered mechanism in which NADP+ binds first. Phenolphthalein inhibited this isoenzyme much more potently than it did the other human liver dihydrodiol dehydrogenases, and was a competitive inhibitor (Ki = 20 nM) that bound to the enzyme-NADP+ complex.

  11. Mitochondrial Aldehyde Dehydrogenase 2 Regulates Revascularization in Chronic Ischemia: Potential Impact on the Development of Coronary Collateral Circulation.

    PubMed

    Liu, Xiangwei; Sun, Xiaolei; Liao, Hua; Dong, Zhen; Zhao, Jingjing; Zhu, Hong; Wang, Peng; Shen, Li; Xu, Lei; Ma, Xin; Shen, Cheng; Fan, Fan; Wang, Cong; Hu, Kai; Zou, Yunzeng; Ge, Junbo; Ren, Jun; Sun, Aijun

    2015-10-01

    Revascularization is an essential process to compensate for cardiac underperfusion and, therefore, preserves cardiac function in the face of chronic ischemic injury. Recent evidence suggested a vital role of aldehyde dehydrogenase 2 (ALDH2) in cardiac protection after ischemia. This study was designed to determine whether ALDH2 regulates chronic ischemia-induced angiogenesis and to explore the underlying mechanism involved. Moreover, the clinical impact of the ALDH2 mutant allele on the development of coronary collateral circulation (CCC) was evaluated. Mice limb ischemia was performed. Compared with wild-type, ALDH2 deletion significantly reduced perfusion recovery, small artery and capillary density, and increased muscle atrophy in this ischemic model. In vitro, ALDH2-knockdown reduced proliferation, migration and hypoxia triggered endothelial tube formation of endothelial cells, the effects of which were restored by ALDH2 transfection. Further examination revealed that ALDH2 regulated angiogenesis possibly through hypoxia-inducible factor-1α/vascular endothelial growth factor pathways. To further discern the role of ALDH2 deficiency in the function of bone marrow stem/progenitor cells, cross bone marrow transplantation was performed between wild-type and ALDH2-knockout mice. However, there was no significant improvement for wild-type bone marrow transplantation into knockout mice. ALDH2 genotyping was screened in 139 patients with chronic total occlusion recruited to Zhongshan Hospital (2011.10-2014.4). Patients with poor CCC (Rentrop 0-1; n=51) exhibited a higher frequency of the AA genotype than those with enriched CCC (Rentrop 2-3; n=88; 11.76% versus 1.14%; P=0 0.01). However, the AA group displayed less enriched CCC frequency in Logistic regression model when compared with the GG group (odds ratio=0.08; 95% confidence interval, 0.009-0.701; P=0 0.026). Furthermore, serum vascular endothelial growth factor level tended to be lower in patients with ALDH2

  12. Characterization of an Arxula adeninivorans alcohol dehydrogenase involved in the metabolism of ethanol and 1-butanol.

    PubMed

    Kasprzak, Jakub; Rauter, Marion; Riechen, Jan; Worch, Sebastian; Baronian, Kim; Bode, Rüdiger; Schauer, Frieder; Kunze, Gotthard

    2016-05-01

    In this study, alcohol dehydrogenase 1 from Arxula adeninivorans (Aadh1p) was identified and characterized. Aadh1p showed activity with short and medium chain length primary alcohols in the forward reaction and their aldehydes in the reverse reaction. Aadh1p has 64% identity with Saccharomyces cerevisiae Adh1p, is localized in the cytoplasm and uses NAD(+) as cofactor. Gene expression analysis showed a low level increase in AADH1 gene expression with ethanol, pyruvate or xylose as the carbon source. Deletion of the AADH1 gene affects growth of the cells with 1-butanol, ethanol and glucose as the carbon source, and a strain which overexpressed the AADH1 gene metabolized 1-butanol more rapidly. An ADH activity assay indicated that Aadh1p is a major enzyme for the synthesis of ethanol and the degradation of 1-butanol in A. adeninivorans. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Characterization of xanthine dehydrogenase and aldehyde oxidase of Marsupenaeus japonicus and their response to microbial pathogen.

    PubMed

    Okamura, Yo; Inada, Mari; Elshopakey, Gehad Elsaid; Itami, Toshiaki

    2018-05-16

    Reactive oxygen species (ROS) play key roles in many physiological processes. In particular, the sterilization mechanism of bacteria using ROS in macrophages is a very important function for biological defense. Xanthine dehydrogenase (XDH) and aldehyde oxidase (AOX), members of the molybdo-flavoenzyme subfamily, are known to generate ROS. Although these enzymes occur in many vertebrates, some insects, and plants, little research has been conducted on XDHs and AOXs in crustaceans. Here, we cloned the entire cDNA sequences of XDH (MjXDH: 4328 bp) and AOX (MjAOX: 4425 bp) from Marsupenaeus japonicus (kuruma shrimp) using reverse transcriptase-polymerase chain reaction (RT-PCR) and random amplification of cDNA ends (RACE). Quantitative real-time RT-PCR transcriptional analysis revealed that MjXDH mRNA is highly expressed in heart and stomach tissues, whereas MjAOX mRNA is highly expressed in the lymphoid organ and intestinal tissues. Furthermore, expression of MjAOX was determined to be up-regulated in the lymphoid organ in response to Vibrio penaeicida at 48 and 72 h after injection; in contrast, hydrogen peroxide (H 2 O 2 ) concentrations increased significantly at 6, 12, 48, and 72 h after injection with white spot syndrome virus (WSSV) and at 72 h after injection with V. penaeicida. To the best of our knowledge, this study is the first to have identified and cloned XDH and AOX from a crustacean species.

  14. ALDH1A3 mutations cause recessive anophthalmia and microphthalmia.

    PubMed

    Fares-Taie, Lucas; Gerber, Sylvie; Chassaing, Nicolas; Clayton-Smith, Jill; Hanein, Sylvain; Silva, Eduardo; Serey, Margaux; Serre, Valérie; Gérard, Xavier; Baumann, Clarisse; Plessis, Ghislaine; Demeer, Bénédicte; Brétillon, Lionel; Bole, Christine; Nitschke, Patrick; Munnich, Arnold; Lyonnet, Stanislas; Calvas, Patrick; Kaplan, Josseline; Ragge, Nicola; Rozet, Jean-Michel

    2013-02-07

    Anophthalmia and microphthalmia (A/M) are early-eye-development anomalies resulting in absent or small ocular globes, respectively. A/M anomalies occur in syndromic or nonsyndromic forms. They are genetically heterogeneous, some mutations in some genes being responsible for both anophthalmia and microphthalmia. Using a combination of homozygosity mapping, exome sequencing, and Sanger sequencing, we identified homozygosity for one splice-site and two missense mutations in the gene encoding the A3 isoform of the aldehyde dehydrogenase 1 (ALDH1A3) in three consanguineous families segregating A/M with occasional orbital cystic, neurological, and cardiac anomalies. ALDH1A3 is a key enzyme in the formation of a retinoic acid gradient along the dorso-ventral axis during early eye development. Transitory expression of mutant ALDH1A3 open reading frames showed that both missense mutations reduce the accumulation of the enzyme, potentially leading to altered retinoic acid synthesis. Although the role of retinoic acid signaling in eye development is well established, our findings provide genetic evidence of a direct link between retinoic-acid-synthesis dysfunction and early-eye-development anomalies in humans. Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  15. Cloning, expression and characterization of an aryl-alcohol dehydrogenase from the white-rot fungus Phanerochaete chrysosporium strain BKM-F-1767

    PubMed Central

    2012-01-01

    Background The white-rot fungus Phanerochaete chrysosporium is among the small group of fungi that can degrade lignin to carbon dioxide while leaving the crystalline cellulose untouched. The efficient lignin oxidation system of this fungus requires cyclic redox reactions involving the reduction of aryl-aldehydes to the corresponding alcohols by aryl-alcohol dehydrogenase. However, the biochemical properties of this enzyme have not been extensively studied. These are of most interest for the design of metabolic engineering/synthetic biology strategies in the field of biotechnological applications of this enzyme. Results We report here the cloning of an aryl-alcohol dehydrogenase cDNA from the white-rot fungus Phanerochaete chrysosporium, its expression in Escherichia coli and the biochemical characterization of the encoded GST and His6 tagged protein. The purified recombinant enzyme showed optimal activity at 37°C and at pH 6.4 for the reduction of aryl- and linear aldehydes with NADPH as coenzyme. NADH could also be the electron donor, while having a higher Km (220 μM) compared to that of NADPH (39 μM). The purified recombinant enzyme was found to be active in the reduction of more than 20 different aryl- and linear aldehydes showing highest specificity for mono- and dimethoxylated Benzaldehyde at positions 3, 4, 3,4 and 3,5. The enzyme was also capable of oxidizing aryl-alcohols with NADP + at 30°C and an optimum pH of 10.3 but with 15 to 100-fold lower catalytic efficiency than for the reduction reaction. Conclusions In this work, we have characterized the biochemical properties of an aryl-alcohol dehydrogenase from the white-rot fungus Phanerochaete chrysosporium. We show that this enzyme functions in the reductive sense under physiological conditions and that it displays relatively large substrate specificity with highest activity towards the natural compound Veratraldehyde. PMID:22742413

  16. The two-step electrochemical oxidation of alcohols using a novel recombinant PQQ alcohol dehydrogenase as a catalyst for a bioanode.

    PubMed

    Takeda, Kouta; Matsumura, Hirotoshi; Ishida, Takuya; Samejima, Masahiro; Igarashi, Kiyohiko; Nakamura, Nobuhumi; Ohno, Hiroyuki

    2013-12-01

    A bioanode has been developed based on the oxidation of ethanol by the recombinant pyrroloquinoline quinone (PQQ) dependent alcohol dehydrogenase from Pseudomonas putidaKT2440 heterologously expressed in Pichia pastoris. The apo form of the recombinant protein (PpADH) was purified and displayed catalytic activity for binding PQQ in the presence of Ca(2+). PpADH exhibited broad substrate specificity towards various alcohols and aldehydes. The Km values for the aldehydes of PpADH were increased compared to those for the alcohols, whereas the kcat values were unaltered. For instance, the Km values at T=298.15K (25 °C) for ethanol and acetaldehyde were 0.21 (± 0.02)mM and 5.8 (± 0.60)mM, respectively. The kcat values for ethanol and acetaldehyde were 24.8 (± 1.2) s(-1) and 31.11.2) s(-1), respectively. The aminoferrocene was used as an electron transfer mediator between PpADH and the electrode during electrochemical experiments. The catalytic currents for the oxidation of alcohol and acetaldehyde by PpADH were also observed in this system. The electric charge for the oxidation of ethanol (Q = 2.09 × 10(-3) · C) was increased two-fold compared to that for the oxidation of acetaldehyde (Q = 0.95 × 10(-3) · C), as determined by chronoamperometric measurements. Thus, we have electrochemically demonstrated the two-step oxidation of ethanol to acetate using only PpADH. © 2013.

  17. Direct enzyme assay evidence confirms aldehyde reductase function of Ydr541cp and Ygl039wp from Saccharomyces cerevisiae.

    PubMed

    Moon, Jaewoong; Liu, Z Lewis

    2015-04-01

    The aldehyde reductase gene ARI1 is a recently characterized member of an intermediate subfamily within the short-chain dehydrogenase/reductase (SDR) superfamily that clarified mechanisms of in situ detoxification of 2-furaldehyde and 5-hydroxymethyl-2-furaldehyde by Saccharomyces cerevisiae. Uncharacterized open reading frames (ORFs) are common among tolerant candidate genes identified for lignocellulose-to-advanced biofuels conversion. This study presents partially purified proteins of two ORFs, YDR541C and YGL039W, and direct enzyme assay evidence against aldehyde-inhibitory compounds commonly encountered during lignocellulosic biomass fermentation processes. Each of the partially purified proteins encoded by these ORFs showed a molecular mass of approximately 38 kDa, similar to Ari1p, a protein encoded by aldehyde reductase gene. Both proteins demonstrated strong aldehyde reduction activities toward 14 aldehyde substrates, with high levels of reduction activity for Ydr541cp toward both aromatic and aliphatic aldehydes. While Ydr541cp was observed to have a significantly higher specific enzyme activity at 20 U/mg using co-factor NADPH, Ygl039wp displayed a NADH preference at 25 U/mg in reduction of butylaldehyde. Amino acid sequence analysis identified a characteristic catalytic triad, Ser, Tyr and Lys; a conserved catalytic motif of Tyr-X-X-X-Lys; and a cofactor-binding sequence motif, Gly-X-X-Gly-X-X-Ala, near the N-terminus that are shared by Ydr541cp, Ygl039wp, Yol151wp/GRE2 and Ari1p. Findings of aldehyde reductase genes contribute to the yeast gene annotation and aids development of the next-generation biocatalyst for advanced biofuels production. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Methanol-Water Aqueous-Phase Reforming with the Assistance of Dehydrogenases at Near-Room Temperature.

    PubMed

    Shen, Yangbin; Zhan, Yulu; Li, Shuping; Ning, Fandi; Du, Ying; Huang, Yunjie; He, Ting; Zhou, Xiaochun

    2018-03-09

    As an excellent hydrogen-storage medium, methanol has many advantages, such as high hydrogen content (12.6 wt %), low cost, and availability from biomass or photocatalysis. However, conventional methanol-water reforming usually proceeds at high temperatures. In this research, we successfully designed a new effective strategy to generate hydrogen from methanol at near-room temperature. The strategy involved two main processes: CH 3 OH→HCOOH→H 2 and NADH→HCOOH→H 2 . The first process (CH 3 OH→HCOOH→H 2 ) was performed by an alcohol dehydrogenase (ADH), an aldehyde dehydrogenase (ALDH), and an Ir catalyst. The second procedure (NADH→HCOOH→H 2 ) was performed by formate dehydrogenase (FDH) and the Ir catalyst. The Ir catalyst used was a previously reported polymer complex catalyst [Cp*IrCl 2 (ppy); Cp*=pentamethylcyclopentadienyl, ppy=polypyrrole] with high catalytic activity for the decomposition of formic acid at room temperature and is compatible with enzymes, coenzymes, and poisoning chemicals. Our results revealed that the optimum hydrogen generation rate could reach up to 17.8 μmol h -1  g cat -1 under weak basic conditions at 30 °C. This will have high impact on hydrogen storage, production, and applications and should also provide new inspiration for hydrogen generation from methanol. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Substrate specificity and catalytic efficiency of aldo-keto reductases with phospholipid aldehydes

    PubMed Central

    Spite, Matthew; Baba, Shahid P.; Ahmed, Yonis; Barski, Oleg A.; Nijhawan, Kanchan; Petrash, J. Mark; Bhatnagar, Aruni; Srivastava, Sanjay

    2007-01-01

    Phospholipid oxidation generates several bioactive aldehydes that remain esterified to the glycerol backbone (‘core’ aldehydes). These aldehydes induce endothelial cells to produce monocyte chemotactic factors and enhance monocyte–endothelium adhesion. They also serve as ligands of scavenger receptors for the uptake of oxidized lipoproteins or apoptotic cells. The biochemical pathways involved in phospholipid aldehyde metabolism, however, remain largely unknown. In the present study, we have examined the efficacy of the three mammalian AKR (aldo-keto reductase) families in catalysing the reduction of phospholipid aldehydes. The model phospholipid aldehyde POVPC [1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine] was efficiently reduced by members of the AKR1, but not by the AKR6 or the ARK7 family. In the AKR1 family, POVPC reductase activity was limited to AKR1A and B. No significant activity was observed with AKR1C enzymes. Among the active proteins, human AR (aldose reductase) (AKR1B1) showed the highest catalytic activity. The catalytic efficiency of human small intestinal AR (AKR1B10) was comparable with the murine AKR1B proteins 1B3 and 1B8. Among the murine proteins AKR1A4 and AKR1B7 showed appreciably lower catalytic activity as compared with 1B3 and 1B8. The human AKRs, 1B1 and 1B10, and the murine proteins, 1B3 and 1B8, also reduced C-7 and C-9 sn-2 aldehydes as well as POVPE [1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphoethanolamine]. AKR1A4, B1, B7 and B8 catalysed the reduction of aldehydes generated in oxidized C16:0-20:4 phosphatidylcholine with acyl, plasmenyl or alkyl linkage at the sn-1 position or C16:0-20:4 phosphatidylglycerol or phosphatidic acid. AKR1B1 displayed the highest activity with phosphatidic acids; AKR1A4 was more efficient with long-chain aldehydes such as 5-hydroxy-8-oxo-6-octenoyl derivatives, whereas AKR1B8 preferred phosphatidylglycerol. These results suggest that proteins of the AKR1A and B families are

  20. Inhibition of Aldehyde Dehydrogenase-Activity Expands Multipotent Myeloid Progenitor Cells with Vascular Regenerative Function.

    PubMed

    Cooper, Tyler T; Sherman, Stephen E; Kuljanin, Miljan; Bell, Gillian I; Lajoie, Gilles A; Hess, David A

    2018-05-01

    Blood-derived progenitor cell transplantation holds potential for the treatment of severe vascular diseases. Human umbilical cord blood (UCB)-derived hematopoietic progenitor cells purified using high aldehyde dehydrogenase (ALDH hi ) activity demonstrate pro-angiogenic functions following intramuscular (i.m.) transplantation into immunodeficient mice with hind-limb ischemia. Unfortunately, UCB ALDH hi cells are rare and prolonged ex vivo expansion leads to loss of high ALDH-activity and diminished vascular regenerative function. ALDH-activity generates retinoic acid, a potent driver of hematopoietic differentiation, creating a paradoxical challenge to expand UCB ALDH hi cells while limiting differentiation and retaining pro-angiogenic functions. We investigated whether inhibition of ALDH-activity during ex vivo expansion of UCB ALDH hi cells would prevent differentiation and expand progeny that retained pro-angiogenic functions after transplantation into non-obese diabetic/severe combined immunodeficient mice with femoral artery ligation-induced unilateral hind-limb ischemia. Human UCB ALDH hi cells were cultured under serum-free conditions for 9 days, with or without the reversible ALDH-inhibitor, diethylaminobenzaldehyde (DEAB). Although total cell numbers were increased >70-fold, the frequency of cells that retained ALDH hi /CD34+ phenotype was significantly diminished under basal conditions. In contrast, DEAB-inhibition increased total ALDH hi /CD34+ cell number by ≥10-fold, reduced differentiation marker (CD38) expression, and enhanced the retention of multipotent colony-forming cells in vitro. Proteomic analysis revealed that DEAB-treated cells upregulated anti-apoptotic protein expression and diminished production of proteins implicated with megakaryocyte differentiation. The i.m. transplantation of DEAB-treated cells into mice with hind-limb ischemia stimulated endothelial cell proliferation and augmented recovery of hind-limb perfusion. DEAB

  1. Cloning and molecular characterization of the betaine aldehyde dehydrogenase involved in the biosynthesis of glycine betaine in white shrimp (Litopenaeus vannamei).

    PubMed

    Delgado-Gaytán, María F; Rosas-Rodríguez, Jesús A; Yepiz-Plascencia, Gloria; Figueroa-Soto, Ciria G; Valenzuela-Soto, Elisa M

    2017-10-01

    The enzyme betaine aldehyde dehydrogenase (BADH) catalyzes the irreversible oxidation of betaine aldehyde to glycine betaine (GB), a very efficient osmolyte accumulated during osmotic stress. In this study, we determined the nucleotide sequence of the cDNA for the BADH from the white shrimp Litopenaeus vannamei (LvBADH). The cDNA was 1882 bp long, with a complete open reading frame of 1524 bp, encoding 507 amino acids with a predicted molecular mass of 54.15 kDa and a pI of 5.4. The predicted LvBADH amino acid sequence shares a high degree of identity with marine invertebrate BADHs. Catalytic residues (C-298, E-264 and N-167) and the decapeptide VTLELGGKSP involved in nucleotide binding and highly conserved in BADHs were identified in the amino acid sequence. Phylogenetic analyses classified LvBADH in a clade that includes ALDH9 sequences from marine invertebrates. Molecular modeling of LvBADH revealed that the protein has amino acid residues and sequence motifs essential for the function of the ALDH9 family of enzymes. LvBADH modeling showed three potential monovalent cation binding sites, one site is located in an intra-subunit cavity; other in an inter-subunit cavity and a third in a central-cavity of the protein. The results show that LvBADH shares a high degree of identity with BADH sequences from marine invertebrates and enzymes that belong to the ALDH9 family. Our findings suggest that the LvBADH has molecular mechanisms of regulation similar to those of other BADHs belonging to the ALDH9 family, and that BADH might be playing a role in the osmoregulation capacity of L. vannamei. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Genetics Home Reference: 3-beta-hydroxysteroid dehydrogenase deficiency

    MedlinePlus

    ... Topic: Adrenal Gland Disorders Health Topic: Assisted Reproductive Technology Health Topic: Infertility Genetic and Rare Diseases Information Center (1 link) 3-beta-hydroxysteroid dehydrogenase deficiency Educational Resources (6 links) Boston Children's Hospital: Congenital Adrenal ...

  3. Identification of Biomarker Genes To Predict Biodegradation of 1,4-Dioxane

    PubMed Central

    Gedalanga, Phillip B.; Pornwongthong, Peerapong; Mora, Rebecca; Chiang, Sheau-Yun Dora; Baldwin, Brett; Ogles, Dora

    2014-01-01

    Bacterial multicomponent monooxygenase gene targets in Pseudonocardia dioxanivorans CB1190 were evaluated for their use as biomarkers to identify the potential for 1,4-dioxane biodegradation in pure cultures and environmental samples. Our studies using laboratory pure cultures and industrial activated sludge samples suggest that the presence of genes associated with dioxane monooxygenase, propane monooxygenase, alcohol dehydrogenase, and aldehyde dehydrogenase are promising indicators of 1,4-dioxane biotransformation; however, gene abundance was insufficient to predict actual biodegradation. A time course gene expression analysis of dioxane and propane monooxygenases in Pseudonocardia dioxanivorans CB1190 and mixed communities in wastewater samples revealed important associations with the rates of 1,4-dioxane removal. In addition, transcripts of alcohol dehydrogenase and aldehyde dehydrogenase genes were upregulated during biodegradation, although only the aldehyde dehydrogenase was significantly correlated with 1,4-dioxane concentrations. Expression of the propane monooxygenase demonstrated a time-dependent relationship with 1,4-dioxane biodegradation in P. dioxanivorans CB1190, with increased expression occurring after over 50% of the 1,4-dioxane had been removed. While the fraction of P. dioxanivorans CB1190-like bacteria among the total bacterial population significantly increased with decrease in 1,4-dioxane concentrations in wastewater treatment samples undergoing active biodegradation, the abundance and expression of monooxygenase-based biomarkers were better predictors of 1,4-dioxane degradation than taxonomic 16S rRNA genes. This study illustrates that specific bacterial monooxygenase and dehydrogenase gene targets together can serve as effective biomarkers for 1,4-dioxane biodegradation in the environment. PMID:24632253

  4. Genomic structure of rat 3alpha-hydroxysteroid/dihydrodiol dehydrogenase (3alpha-HSD/DD, AKR1C9).

    PubMed

    Lin, H K; Hung, C F; Moore, M; Penning, T M

    1999-11-01

    Rat liver 3alpha-hydroxysteroid/dihydrodiol dehydrogenase (3alpha-HSD/DD) is a member of the aldo-keto reductase (AKR) superfamily. It is involved in the inactivation of steroid hormones and the metabolic activation of polycyclic aromatic hydrocarbons (PAH) by converting trans-dihydrodiols into reactive and redox-active o-quinones. The structure of the 5'-flanking region of the gene and factors involved in the constitutive and regulated expression of this gene have been reported [H.-K. Lin, T.M. Penning, Cloning, sequencing, and functional analysis of the 5'-flanking region of the rat 3alpha-hydroxysteroid/dihydrodiol dehydrogenase gene, Cancer Res. 55 (1995) 4105-4113]. We now describe the complete genomic structure of the rat type 1 3alpha-HSD/DD gene. Charon 4A and P1 genomic clones contained at least three rat genes (type 1, type 2 and type 3 3alpha-HSD/DD) each of which encoded for the same open reading frame (ORF) but differed in their exon-intron organization. 5'-RACE confirmed that the type 1 3alpha-HSD/DD gene encodes for the dominant transcript in rat liver and it was the regulation of this gene that was previously studied. The rat type 1 3alpha-HSD/DD gene is 30 kb in length and consists of nine exons and eight introns. Exon 9 encodes +931 to 966 bp of the ORF and the 1292 bp 3'-UTR implicated in mRNA stability. This genomic structure is nearly identical to the homologous human genes, type 1 3alpha-HSD (chlordecone reductase/DD4, AKR1C4), type 2 3alpha-HSD (AKR1C3) and type 3 3alpha-HSD (bile-acid binding protein, AKR1C2) genes. Three different cDNA's containing identical ORFs for 3alpha-HSD have been reported suggesting that all three genes may be expressed in rat liver. Using 5' primers corresponding to the 5'-UTR's of the three different cDNA's only one PCR fragment was obtained and corresponded to the type 1 3alpha-HSD/DD gene. These data suggested that the type 2 and type 3 3alpha-HSD/DD genes are not abundantly expressed in rat liver. It is unknown

  5. Preparation of 3,5-disubstituted pyrazoles and isoxazoles from terminal alkynes, aldehydes, hydrazines, and hydroxylamine.

    PubMed

    Harigae, Ryo; Moriyama, Katsuhiko; Togo, Hideo

    2014-03-07

    The reaction of terminal alkynes with n-BuLi, and then with aldehydes, followed by the treatment with molecular iodine, and subsequently hydrazines or hydroxylamine provided the corresponding 3,5-disubstituted pyrazoles or isoxazoles in good yields with high regioselectivity, through the formations of propargyl secondary alkoxides and α-alkynyl ketones. The present reactions are one-pot preparation of 3,5-disubstituted pyrazoles from terminal alkynes, aldehydes, molecular iodine, and hydrazines, and 3,5-disubstituted isoxazoles from terminal alkynes, aldehydes, molecular iodine, and hydroxylamine.

  6. A kinetic estimate of the free aldehyde content of aldoses

    NASA Technical Reports Server (NTRS)

    Dworkin, J. P.; Miller, S. L.; Bada, J. L. (Principal Investigator)

    2000-01-01

    The relative free aldehyde content of eight hexoses and four pentoses has been estimated within about 10% from the rate constants for their reaction with urazole (1,2,4-triazole-3,5-dione). These values of the percent free aldehyde are in agreement with those estimated from CD measurements, but are more accurate. The relative free aldehyde contents for the aldoses were then correlated to various literature NMR measurements to obtain the absolute values. This procedure was also done for three deoxyaldoses, which react much more rapidly than can be accounted for by the free aldehyde content. This difference in reactivity between aldoses and deoxyaldoses is due to the inductive effect of the H versus the OH on C-2'. This may help explain why deoxyribonucleosides hydrolyze much more rapidly than ribonucleosides.

  7. Structural studies of MFE-1: the 1.9 A crystal structure of the dehydrogenase part of rat peroxisomal MFE-1.

    PubMed

    Taskinen, Jukka P; Kiema, Tiila R; Hiltunen, J Kalervo; Wierenga, Rik K

    2006-01-27

    The 1.9 A structure of the C-terminal dehydrogenase part of the rat peroxisomal monomeric multifunctional enzyme type 1 (MFE-1) has been determined. In this construct (residues 260-722 and referred to as MFE1-DH) the N-terminal hydratase part of MFE-1 has been deleted. The structure of MFE1-DH shows that it consists of an N-terminal helix, followed by a Rossmann-fold domain (domain C), followed by two tightly associated helical domains (domains D and E), which have similar topology. The structure of MFE1-DH is compared with the two known homologous structures: human mitochondrial 3-hydroxyacyl-CoA dehydrogenase (HAD; sequence identity is 33%) (which is dimeric and monofunctional) and with the dimeric multifunctional alpha-chain (alphaFOM; sequence identity is 28%) of the bacterial fatty acid beta-oxidation alpha2beta2-multienzyme complex. Like MFE-1, alphaFOM has an N-terminal hydratase part and a C-terminal dehydrogenase part, and the structure comparisons show that the N-terminal helix of MFE1-DH corresponds to the alphaFOM linker helix, located between its hydratase and dehydrogenase part. It is also shown that this helix corresponds to the C-terminal helix-10 of the hydratase/isomerase superfamily, suggesting that functionally it belongs to the N-terminal hydratase part of MFE-1.

  8. Effect of peptide aldehydes with IL-1 beta converting enzyme inhibitory properties on IL-1 alpha and IL-1 beta production in vitro.

    PubMed

    Németh, K; Patthy, M; Fauszt, I; Széll, E; Székely, J I; Bajusz, S

    1995-12-01

    Tripeptide and pentapeptide aldehydes as substrate-base inhibitors of cysteine proteases were designed in our laboratory for the inhibition of interleukin-1 beta converting enzyme (ICE), a recently described cysteine protease responsible for the processing of IL-1 beta. The biological effectivity of the peptide aldehydes was studied in THP-1 cells and human whole blood. The released and cell-associated IL-1 alpha and IL-1 beta levels were determined by ELISA from the supernatants and cell lysates, respectively. The total IL-1 like bioactivity was assayed by the D10 G4.1 cell proliferation method. The tripeptide aldehyde (Z-Val-His-Asp-H) and pentapeptide aldehyde (Eoc-Ala-Tyr-Val-Ala-Asp-H) significantly reduced IL-1 beta levels in the supernatants in relatively high concentrations (10-100 microM), but the IL-1 alpha release was unaffected by these peptides. However, a considerable decrease in the cell-associated IL-1 beta and IL-1 alpha levels was observed. N-terminal extension of the tripeptide aldehyde yielded even more potent inhibitors. Amino acid substitution at the P2 position did not cause considerable changes in the inhibitory activity. The peptide aldehydes suppressed the IL-1 beta production in a reversible manner, whereas dexamethasone, a glucocorticoid, had a prolonged inhibitory effect. The inhibitory effect of these peptides and that of dexamethasone appeared to be additive. These findings indicate that these peptide aldehydes might be used as IL-beta inhibitory agents in experimental models in which IL-1 beta is a key mediator or ICE is implicated.

  9. A comparative multidimensional LC-MS proteomic analysis reveals mechanisms for furan aldehyde detoxification in Thermoanaerobacter pseudethanolicus 39E

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clarkson, Sonya M.; Hamilton-Brehm, Scott D.; Giannone, Richard J.

    Background: Chemical and physical pretreatment of lignocellulosic biomass improves substrate reactivity for increased microbial biofuel production, but also restricts growth via the release of furan aldehydes such as furfural and 5-hydroxymethylfurfural (5-HMF). The physiological effects of these inhibitors on thermophilic, fermentative bacteria is important to understand; especially as cellulolytic strains are being developed for consolidated bioprocessing (CBP) of lignocellulosic feedstocks. Identifying mechanisms for detoxification of aldehydes in naturally resistant strains such as Thermoanaerobacter spp. may also enable improvements in candidate CBP microorganisms. Results: T. pseudethanolicus 39E, an anaerobic, saccharolytic thermophile, was found to grow readily in the presence of 30more » mM furfural and 20 mM 5-HMF and reduce these aldehydes to their respective alcohols in situ. The proteomes of T. pseudethanolicus 39E grown in the presence or absence of 15 mM furfural were compared to identify upregulated enzymes potentially responsible for the observed reduction. A total of 225 proteins were differentially regulated in response to the 15 mM furfural treatment with 152 upregulated vs. 73 downregulated. Only 86 proteins exhibited a 2-fold change in abundance in either direction. Of these, 53 were upregulated in the presence of furfural and 33 were downregulated. Two oxidoreductases were upregulated at least 2-fold by furfural and were targeted for further investigation: Teth39_1597, encodes a predicted butanol dehydrogenase (BdhA) and Teth39_1598, a predicted aldo/keto reductase (AKR). Both genes were cloned from T. pseudethanolicus 39E, with the respective enzymes overexpressed in E. coli and specific activities determined against a variety of aldehydes. BdhA showed significant activity with all aldehydes tested, including furfural and 5-HMF, using NADPH as the cofactor. AKR also showed significant activity with NADPH, but only with four carbon butyr

  10. A comparative multidimensional LC-MS proteomic analysis reveals mechanisms for furan aldehyde detoxification in Thermoanaerobacter pseudethanolicus 39E

    DOE PAGES

    Clarkson, Sonya M.; Hamilton-Brehm, Scott D.; Giannone, Richard J.; ...

    2014-12-03

    Background: Chemical and physical pretreatment of lignocellulosic biomass improves substrate reactivity for increased microbial biofuel production, but also restricts growth via the release of furan aldehydes such as furfural and 5-hydroxymethylfurfural (5-HMF). The physiological effects of these inhibitors on thermophilic, fermentative bacteria is important to understand; especially as cellulolytic strains are being developed for consolidated bioprocessing (CBP) of lignocellulosic feedstocks. Identifying mechanisms for detoxification of aldehydes in naturally resistant strains such as Thermoanaerobacter spp. may also enable improvements in candidate CBP microorganisms. Results: T. pseudethanolicus 39E, an anaerobic, saccharolytic thermophile, was found to grow readily in the presence of 30more » mM furfural and 20 mM 5-HMF and reduce these aldehydes to their respective alcohols in situ. The proteomes of T. pseudethanolicus 39E grown in the presence or absence of 15 mM furfural were compared to identify upregulated enzymes potentially responsible for the observed reduction. A total of 225 proteins were differentially regulated in response to the 15 mM furfural treatment with 152 upregulated vs. 73 downregulated. Only 86 proteins exhibited a 2-fold change in abundance in either direction. Of these, 53 were upregulated in the presence of furfural and 33 were downregulated. Two oxidoreductases were upregulated at least 2-fold by furfural and were targeted for further investigation: Teth39_1597, encodes a predicted butanol dehydrogenase (BdhA) and Teth39_1598, a predicted aldo/keto reductase (AKR). Both genes were cloned from T. pseudethanolicus 39E, with the respective enzymes overexpressed in E. coli and specific activities determined against a variety of aldehydes. BdhA showed significant activity with all aldehydes tested, including furfural and 5-HMF, using NADPH as the cofactor. AKR also showed significant activity with NADPH, but only with four carbon butyr

  11. Electrophilic aldehyde products of lipid peroxidation selectively adduct to heat shock protein 90 and arylsulfatase A in stallion spermatozoa.

    PubMed

    Hall, Sally E; Aitken, R John; Nixon, Brett; Smith, Nathan D; Gibb, Zamira

    2017-01-01

    Oxidative stress is a major determinant of mammalian sperm function stimulating lipid peroxidation cascades that culminate in the generation of potentially cytotoxic aldehydes. The aim of this study was to assess the impact of such aldehydes on the functionality of stallion spermatozoa. The impact of exposure to exogenous acrolein (ACR) and 4-hydroxynonenal (4HNE) was manifested in a highly significant dose- and time-dependent increase in mitochondrial reactive oxygen species (ROS), total cellular ROS, a decrease in sperm motility, and a time-dependent increase in lipid peroxidation. Notably, low doses of ACR and 4HNE also caused a significant decrease in zona binding. In contrast, exogenous malondialdehyde, a commonly used marker of oxidative stress, had little impact on the various sperm parameters assessed. In accounting for the negative physiological impact of ACR and 4HNE, it was noted that both aldehydes readily adducted to sperm proteins located predominantly within the head, proximal centriole, and tail. The detoxifying activity of mitochondrial aldehyde dehydrogenase 2 appeared responsible for a lack of adduction in the midpiece; however, this activity was overwhelmed by 24 h of electrophilic aldehyde exposure. Sequencing of the dominant proteins targeted for ACR and 4HNE covalent modification identified heat shock protein 90 alpha (cytosolic) class A member 1 and arylsulfatase A, respectively. These collective findings may prove useful in the identification of diagnostic biomarkers of stallion fertility and resolving the mechanistic basis of sperm dysfunction in this species. © The Authors 2016. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please journals.permissions@oup.com.

  12. Recent advances in biotechnological applications of alcohol dehydrogenases.

    PubMed

    Zheng, Yu-Guo; Yin, Huan-Huan; Yu, Dao-Fu; Chen, Xiang; Tang, Xiao-Ling; Zhang, Xiao-Jian; Xue, Ya-Ping; Wang, Ya-Jun; Liu, Zhi-Qiang

    2017-02-01

    Alcohol dehydrogenases (ADHs), which belong to the oxidoreductase superfamily, catalyze the interconversion between alcohols and aldehydes or ketones with high stereoselectivity under mild conditions. ADHs are widely employed as biocatalysts for the dynamic kinetic resolution of racemic substrates and for the preparation of enantiomerically pure chemicals. This review provides an overview of biotechnological applications for ADHs in the production of chiral pharmaceuticals and fine chemicals.

  13. Catalysis of nitrite generation from nitroglycerin by glyceraldehyde-3-phosphate dehydrogenase (GAPDH).

    PubMed

    Seabra, Amedea B; Ouellet, Marc; Antonic, Marija; Chrétien, Michelle N; English, Ann M

    2013-11-30

    Vascular relaxation to nitroglycerin (glyceryl trinitrate; GTN) requires its bioactivation by mechanisms that remain controversial. We report here that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) catalyzes the release of nitrite from GTN. In assays containing dithiothreitol (DTT) and NAD(+), the GTN reductase activity of purified GAPDH produces nitrite and 1,2-GDN as the major products. A vmax of 2.6nmolmin(-)(1)mg(-)(1) was measured for nitrite production by GAPDH from rabbit muscle and a GTN KM of 1.2mM. Reductive denitration of GTN in the absence of DTT results in dose- and time-dependent inhibition of GAPDH dehydrogenase activity. Disulfiram, a thiol-modifying drug, inhibits both the dehydrogenase and GTN reductase activity of GAPDH, while DTT or tris(2-carboxyethyl)phosphine reverse the GTN-induced inhibition. Incubation of intact human erythrocytes or hemolysates with 2mM GTN for 60min results in 50% inhibition of GAPDH's dehydrogenase activity, indicating that GTN is taken up by these cells and that the dehydrogenase is a target of GTN. Thus, erythrocyte GAPDH may contribute to GTN bioactivation. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  14. Effect of Lipid Peroxidation Products on the Activity of Human Retinol Dehydrogenase 12 (RDH12) and Retinoid Metabolism

    PubMed Central

    Lee, Seung-Ah; Belyaeva, Olga V.; Kedishvili, Natalia Y.

    2008-01-01

    SUMMARY Mutations in human Retinol Dehydrogenase 12 (RDH12) are known to cause photoreceptor cell death but the physiological function of RDH12 in photoreceptors remains poorly understood. In vitro, RDH12 recognizes both retinoids and medium-chain aldehydes as substrates. Our previous study suggested that RDH12 protects cells against toxic levels of retinaldehyde and retinoic acid [Lee et al., J. Biol. Chem. 282 (2007) 35621–35628]. Here, we investigated whether RDH12 can also protect cells against highly reactive medium-chain aldehydes. Analysis of cell survival demonstrated that RDH12 was protective against nonanal but not against 4-hydroxynonenal. At high concentrations, nonanal inhibited the activity of RDH12 towards retinaldehyde, suggesting that nonanal was metabolized by RDH12. 4-Hydroxynonenal did not inhibit the RDH12 retinaldehyde reductase activity, but it strongly inhibited the activities of lecithin:retinol acyl transferase and aldehyde dehydrogenase, resulting in decreased levels of retinyl esters and retinoic acid and accumulation of unesterified retinol. Thus, the results of this study showed that RDH12 is more effective in protection against retinaldehyde than against medium-chain aldehydes, and that medium-chain aldehydes, especially 4-hydroxynonenal, severely disrupt cellular retinoid homeostasis. Together, these findings provide a new insight into the effects of lipid peroxidation products and the impact of oxidative stress on retinoid metabolism. PMID:18396173

  15. Simple one-pot conversion of aldehydes and ketones to enals.

    PubMed

    Valenta, Petr; Drucker, Natalie A; Bode, Jeffrey W; Walsh, Patrick J

    2009-05-21

    A simple and efficient method to convert aldehydes into alpha,beta-unsaturated aldehydes with a two-carbon homologation is presented. Hydroboration of ethoxy acetylene with BH(3).SMe(2) generates tris(ethoxyvinyl) borane. Transmetalation with diethylzinc, addition to aldehydes or ketones, and acidic workup affords enals. When the addition is quenched with anilinium hydrochloride, 1,2-dithioglycol, or acetic anhydride, the unsaturated imine, dithiolane, or 1,1-diacetate is isolated in high yield. These transformations can be performed in a one-pot procedure.

  16. The E3 ubiquitin-ligase SEVEN IN ABSENTIA like 7 mono-ubiquitinates glyceraldehyde-3-phosphate dehydrogenase 1 isoform in vitro and is required for its nuclear localization in Arabidopsis thaliana.

    PubMed

    Peralta, Diego A; Araya, Alejandro; Busi, Maria V; Gomez-Casati, Diego F

    2016-01-01

    The E3 ubiquitin-protein ligases are associated to various processes such as cell cycle control and diverse developmental pathways. Arabidopsis thaliana SEVEN IN ABSENTIA like 7, which has ubiquitin ligase activity, is located in the nucleus and cytosol and is expressed at several stages in almost all plant tissues suggesting an important role in plant functions. However, the mechanism underlying the regulation of this protein is unknown. Since we found that the SEVEN IN ABSENTIA like 7 gene expression is altered in plants with impaired mitochondria, and in plants deficient in the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase 1, we decided to study the possible interactions between both proteins as potential partners in plant signaling functions. We found that SEVEN IN ABSENTIA like 7 is able to interact in vitro with glyceraldehyde-3-phosphate dehydrogenase and that the Lys231 residue of the last is essential for this function. Following the interaction, a concomitant increase in the glyceraldehyde-3-phosphate dehydrogenase catalytic activity was observed. However, when SEVEN IN ABSENTIA like 7 was supplemented with E1 and E2 proteins to form a complete E1-E2-E3 modifier complex, we observed the mono-ubiquitination of glyceraldehyde-3-phosphate dehydrogenase 1 at the Lys76 residue and a dramatic decrease of its catalytic activity. Moreover, we found that localization of glyceraldehyde-3-phosphate dehydrogenase 1 in the nucleus is dependent on the expression SEVEN IN ABSENTIA like 7. These observations suggest that the association of both proteins might result in different biological consequences in plants either through affecting the glycolytic flux or via cytoplasm-nucleus relocation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Mechanisms of aldehyde-induced adenosinetriphosphatase activities of kinases.

    PubMed

    Rendina, A R; Cleland, W W

    1984-10-23

    Aldehyde analogues of the normal alcohol substrates induce ATPase activities by glycerokinase (D-glyceraldehyde), fructose-6-phosphate kinase (2,5-anhydromannose 6-phosphate), fructokinase (2,5-anhydromannose or 2,5-anhydrotalose), hexokinase (D-gluco-hexodialdose), choline kinase (betaine aldehyde), and pyruvate kinase (glyoxylate). Since purified deuterated aldehydes give V and V/K isotope effects near 1.0 for glycerokinase, fructokinase with 2,5-anhydro[1-2H]talose, hexokinase, choline kinase, and pyruvate kinase, the hydrates of these almost fully hydrated aldehydes are the activators of the ATPase reactions. Fructose-6-phosphate kinase and fructokinase with 2,5-anhydro[1-2H]mannose show V/K deuterium isotope effects of 1.10 and 1.22, respectively, suggesting either that both hydrate and free aldehyde may be activators (predicted values are 1.37 if only the free aldehyde activates the ATPase) or, more likely, that the phosphorylated hydrate breaks down in a rate-limiting step on the enzyme while MgADP is still present and the back-reaction to yield free hydrate in solution is still possible. 18O was transferred from the aldehyde hydrate to phosphate during the ATPase reactions of glycerokinase, fructose-6-phosphate kinase, fructokinase, and hexokinase but not with choline kinase or pyruvate kinase. Thus, direct phosphorylation of the hydrates by the first four enzymes gives the phosphate adduct of the aldehyde, which decomposes nonenzymatically, while with choline kinase and pyruvate kinase the hydrates induce transfer to water (metal-bound hydroxide or water with pyruvate kinase on the basis of pH profiles). Observation of a lag in the release of phosphate from the glycerokinase ATPase reaction at 15 degrees C supports the existence of a phosphorylated hydrate intermediate with a rate constant for breakdown of 0.035-0.043 s-1 at this temperature. Kinases that phosphorylate creatine, 3-phosphoglycerate, and acetate did not exhibit ATPase activities in the

  18. Synthesis and accumulation of aromatic aldehydes in an engineered strain of Escherichia coli.

    PubMed

    Kunjapur, Aditya M; Tarasova, Yekaterina; Prather, Kristala L J

    2014-08-20

    Aromatic aldehydes are useful in numerous applications, especially as flavors, fragrances, and pharmaceutical precursors. However, microbial synthesis of aldehydes is hindered by rapid, endogenous, and redundant conversion of aldehydes to their corresponding alcohols. We report the construction of an Escherichia coli K-12 MG1655 strain with reduced aromatic aldehyde reduction (RARE) that serves as a platform for aromatic aldehyde biosynthesis. Six genes with reported activity on the model substrate benzaldehyde were rationally targeted for deletion: three genes that encode aldo-keto reductases and three genes that encode alcohol dehydrogenases. Upon expression of a recombinant carboxylic acid reductase in the RARE strain and addition of benzoate during growth, benzaldehyde remained in the culture after 24 h, with less than 12% conversion of benzaldehyde to benzyl alcohol. Although individual overexpression results demonstrated that all six genes could contribute to benzaldehyde reduction in vivo, additional experiments featuring subset deletion strains revealed that two of the gene deletions were dispensable under the conditions tested. The engineered strain was next investigated for the production of vanillin from vanillate and succeeded in preventing formation of the byproduct vanillyl alcohol. A pathway for the biosynthesis of vanillin directly from glucose was introduced and resulted in a 55-fold improvement in vanillin titer when using the RARE strain versus the wild-type strain. Finally, synthesis of the chiral pharmaceutical intermediate L-phenylacetylcarbinol (L-PAC) was demonstrated from benzaldehyde and glucose upon expression of a recombinant mutant pyruvate decarboxylase in the RARE strain. Beyond allowing accumulation of aromatic aldehydes as end products in E. coli, the RARE strain expands the classes of chemicals that can be produced microbially via aldehyde intermediates.

  19. Asymmetric intramolecular α-cyclopropanation of aldehydes using a donor/acceptor carbene mimetic

    PubMed Central

    Luo, Chaosheng; Wang, Zhen; Huang, Yong

    2015-01-01

    Enantioselective α-alkylation of carbonyl is considered as one of the most important processes for asymmetric synthesis. Common alkylation agents, that is, alkyl halides, are notorious substrates for both Lewis acids and organocatalysts. Recently, olefins emerged as a benign alkylating species via photo/radical mechanisms. However, examples of enantioselective alkylation of aldehydes/ketones are scarce and direct asymmetric dialkylation remains elusive. Here we report an intramolecular α-cyclopropanation reaction of olefinic aldehydes to form chiral cyclopropane aldehydes. We demonstrate that an α-iodo aldehyde can function as a donor/acceptor carbene equivalent, which engages in a formal [2+1] annulation with a tethered double bond. Privileged bicyclo[3.1.0]hexane-type scaffolds are prepared in good optical purity using a chiral amine. The synthetic utility of the products is demonstrated by versatile transformations of the bridgehead formyl functionality. We expect the concept of using α-iodo iminium as a donor/acceptor carbene surrogate will find wide applications in chemical reaction development. PMID:26644194

  20. Widespread Non-Hematopoietic Tissue Distribution by Transplanted Human Progenitor Cells with High Aldehyde Dehydrogenase Activity

    PubMed Central

    Hess, David A.; Craft, Timothy P.; Wirthlin, Louisa; Hohm, Sarah; Zhou, Ping; Eades, William C.; Creer, Michael H.; Sands, Mark S.; Nolta, Jan A.

    2011-01-01

    Transplanted adult progenitor cells distribute to peripheral organs and can promote endogenous cellular repair in damaged tissues. However, development of cell-based regenerative therapies has been hindered by the lack of pre-clinical models to efficiently assess multiple organ distribution and difficulty defining human cells with regenerative function. After transplantation into beta-glucuronidase (GUSB)-deficient NOD/SCID/MPSVII mice, we characterized the distribution of lineage depleted human umbilical cord blood-derived cells purified by selection using high aldehyde dehydrogenase activity (ALDH) with CD133 co-expression. ALDHhi or ALDHhiCD133+ cells produced robust hematopoietic reconstitution, and variable levels of tissue distribution in multiple organs. GUSB+ donor cells that co-expressed human (HLA-A,B,C) and hematopoietic (CD45+) cell surface markers were the primary cell phenotype found adjacent to the vascular beds of several tissues, including islet and ductal regions of mouse pancreata. In contrast, variable phenotypes were detected in the chimeric liver, with HLA+/CD45+ cells demonstrating robust GUSB expression adjacent to blood vessels, and CD45−/HLA− cells with diluted GUSB expression predominant in the liver parenchyma. However, true non-hematopoietic human (HLA+/CD45−) cells were rarely detected in other peripheral tissues, suggesting that these GUSB+/HLA−/CD45− cells in the liver were a result of downregulated human surface marker expression in vivo, not widespread seeding of non-hematopoietic cells. However, relying solely on continued expression of cell surface markers, as employed in traditional xenotransplantation models, may underestimate true tissue distribution. ALDH-expressing progenitor cells demonstrated widespread and tissue-specific distribution of variable cellular phenotypes, indicating that these adult progenitor cells should be explored in transplantation models of tissue damage. PMID:18055447

  1. Garcinol from Garcinia indica Downregulates Cancer Stem-like Cell Biomarker ALDH1A1 in Nonsmall Cell Lung Cancer A549 Cells through DDIT3 Activation.

    PubMed

    Wang, Jinhan; Wang, Liwen; Ho, Chi-Tang; Zhang, Kunsheng; Liu, Qiang; Zhao, Hui

    2017-05-10

    Nonsmall cell lung cancer (NSCLC) is the predominant type of lung cancer. Patients with NSCLC show high mortality rates because of failure to clean up cancer stem cells (CSCs). The anticancer activity of phytochemical garcinol has been identified in various cancer cell models. However, the effect of garcinol on NSCLC cell lines is still lacking. Of the NSCLC cell lines we tested, A549 cells were the most sensitive to garcinol. Interestingly, Aldehyde Dehydrogenase 1 Family Member A1 (ALDH1A1) was preferentially expressed in A549 cells and downregulated by the addition of garcinol. We also found that garcinol enriched DNA damage-inducible transcript 3 (DDIT3) and then altered DDIT3-CCAAT-enhancer-binding proteins beta (C/EBPβ) interaction resulting in a decreased binding of C/EBPβ to the endogenous ALDH1A1 promoter. Furthermore, garcinol's inhibition of ALDH1A1 was identified in a xenograft mice model. Garcinol repressed ALDH1A1 transcription in A549 cells through alterations in the interaction between DDIT3 and C/EBPβ. Garcinol could be a potential dietary phytochemical candidate for NSCLCs patients whose tumors harbored high ALDH1A1 expression.

  2. Reactions of the selected ion flow tube mass spectrometry reagent ions H3O(+) and NO(+) with a series of volatile aldehydes of biogenic significance.

    PubMed

    Smith, David; Chippendale, Thomas W E; Španěl, Patrik

    2014-09-15

    It has been shown that aldehydes are often present in biogenic media. For their analysis by selected ion flow tube mass spectrometry (SIFT-MS), the rate coefficients and the product ion distributions for the reactions of the analyte ions H3O(+) and NO(+) with volatile aldehydes in the presence of water vapour are required. The reactions of H3O(+) and NO(+) ions have been studied with a series of n-aldehydes ranging from acetaldehyde (designated as C2), through undecanal (C11) under the conditions used for SIFT-MS analyses (1 Torr He, 0.1 Torr air sample, 300 K) and over a range of sample gas absolute humidity from 1% to 7%. For comparison, the C5 pentanal isomer 3-methyl butanal, the unsaturated trans-2-pentenal and trans-2-octenal and the aromatic benzaldehyde were also included in the study. The H3O(+) reactions led to the formation of protonated molecules MH(+) and their hydrates MH(+)(H2O)0,1,2,3 , and (MH(+)-H2O). The NO(+) reactions resulted in the production of NO(+)M adduct ions and of [M-H](+) fragment ions. The percentages of the different product ions for each aldehyde are seen to be dependent on the air sample humidity. Kinetic modelling was used to quantitatively explain these observations and to obtain rate coefficients for the association reactions producing NO(+) M adduct ions. This detailed study has provided the kinetics data, in particular the product ion distributions, for the reactions of a number of volatile aldehydes, which allows their analyses by SIFT-MS in humid air, including exhaled breath, food emanations and other biogenic media. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Purification and characterization of vanillin dehydrogenases from alkaliphile Micrococcus sp. TA1 and neutrophile Burkholderia cepacia TM1.

    PubMed

    Mitsui, Ryoji; Hirota, Mizuho; Tsuno, Takuo; Tanaka, Mitsuo

    2010-02-01

    Vanillin dehydrogenases (VDHs) were purified and characterized from two bacterial strains that have different pH dependencies for growth. The alkaliphile Micrococcus sp. TA1, isolated from an alkaline spa, can grow on several aromatic compounds such as ferulic acid, vanillin, vanillic acid, and protocatechuic acid under alkaline conditions. The neutrophile Burkholderia cepacia TM1, which was isolated previously, also grew on the above-mentioned compounds because they functioned as the sole carbon source under neutral conditions. Purified VDHs showed activities toward some aromatic aldehydes. These enzymes have the same subunit molecular mass of about 57 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, but differed in some of their observed properties. Native molecular masses also differed between the purified enzymes. These were 250 kDa for the enzyme from alkaliphilic strain TA1 and 110 kDa for that from neutrophilic strain TM1, as determined by gel filtration. The enzyme from strain TA1 required NADP(+) as a coenzyme for its activity, but that from strain TM1 required NAD(+). These results are important because this is the first report of an alkaliphilic bacterium consuming lignin monomers.

  4. Estrogen and androgen-converting enzymes 17β-hydroxysteroid dehydrogenase and their involvement in cancer: with a special focus on 17β-hydroxysteroid dehydrogenase type 1, 2, and breast cancer

    PubMed Central

    Hilborn, Erik; Stål, Olle; Jansson, Agneta

    2017-01-01

    Sex steroid hormones such as estrogens and androgens are involved in the development and differentiation of the breast tissue. The activity and concentration of sex steroids is determined by the availability from the circulation, and on local conversion. This conversion is primarily mediated by aromatase, steroid sulfatase, and 17β-hydroxysteroid dehydrogenases. In postmenopausal women, this is the primary source of estrogens in the breast. Up to 70-80% of all breast cancers express the estrogen receptor-α, responsible for promoting the growth of the tissue. Further, 60-80% express the androgen receptor, which has been shown to have tissue protective effects in estrogen receptor positive breast cancer, and a more ambiguous response in estrogen receptor negative breast cancers. In this review, we summarize the function and clinical relevance in cancer for 17β-hydroxysteroid dehydrogenases 1, which facilitates the reduction of estrone to estradiol, dehydroepiandrosterone to androstendiol and dihydrotestosterone to 3α- and 3β-diol as well as 17β-hydroxysteroid dehydrogenases 2 which mediates the oxidation of estradiol to estrone, testosterone to androstenedione and androstendiol to dehydroepiandrosterone. The expression of 17β-hydroxysteroid dehydrogenases 1 and 2 alone and in combination has been shown to predict patient outcome, and inhibition of 17β-hydroxysteroid dehydrogenases 1 has been proposed to be a prime candidate for inhibition in patients who develop aromatase inhibitor resistance or in combination with aromatase inhibitors as a first line treatment. Here we review the status of inhibitors against 17β-hydroxysteroid dehydrogenases 1. In addition, we review the involvement of 17β-hydroxysteroid dehydrogenases 4, 5, 7, and 14 in breast cancer. PMID:28430630

  5. Estrogen and androgen-converting enzymes 17β-hydroxysteroid dehydrogenase and their involvement in cancer: with a special focus on 17β-hydroxysteroid dehydrogenase type 1, 2, and breast cancer.

    PubMed

    Hilborn, Erik; Stål, Olle; Jansson, Agneta

    2017-05-02

    Sex steroid hormones such as estrogens and androgens are involved in the development and differentiation of the breast tissue. The activity and concentration of sex steroids is determined by the availability from the circulation, and on local conversion. This conversion is primarily mediated by aromatase, steroid sulfatase, and 17β-hydroxysteroid dehydrogenases. In postmenopausal women, this is the primary source of estrogens in the breast. Up to 70-80% of all breast cancers express the estrogen receptor-α, responsible for promoting the growth of the tissue. Further, 60-80% express the androgen receptor, which has been shown to have tissue protective effects in estrogen receptor positive breast cancer, and a more ambiguous response in estrogen receptor negative breast cancers. In this review, we summarize the function and clinical relevance in cancer for 17β-hydroxysteroid dehydrogenases 1, which facilitates the reduction of estrone to estradiol, dehydroepiandrosterone to androstendiol and dihydrotestosterone to 3α- and 3β-diol as well as 17β-hydroxysteroid dehydrogenases 2 which mediates the oxidation of estradiol to estrone, testosterone to androstenedione and androstendiol to dehydroepiandrosterone. The expression of 17β-hydroxysteroid dehydrogenases 1 and 2 alone and in combination has been shown to predict patient outcome, and inhibition of 17β-hydroxysteroid dehydrogenases 1 has been proposed to be a prime candidate for inhibition in patients who develop aromatase inhibitor resistance or in combination with aromatase inhibitors as a first line treatment. Here we review the status of inhibitors against 17β-hydroxysteroid dehydrogenases 1. In addition, we review the involvement of 17β-hydroxysteroid dehydrogenases 4, 5, 7, and 14 in breast cancer.

  6. Two-carbon homologation of aldehydes and ketones to a,ß-unsaturated aldehydes

    USDA-ARS?s Scientific Manuscript database

    Phosphonate reagents were developed for the two-carbon homologation of aldehydes or ketones to unbranched- or methyl-branched a,ß-unsaturated aldehydes. The phosphonate reagents, diethyl methylformyl-2-phosphonate dimethylhydrazone and diethyl ethylformyl-2-phosphonate dimethylhydrazone, contained a...

  7. Molecular characterization of three 3-ketosteroid-Δ(1)-dehydrogenase isoenzymes of Rhodococcus ruber strain Chol-4.

    PubMed

    Fernández de las Heras, Laura; van der Geize, Robert; Drzyzga, Oliver; Perera, Julián; María Navarro Llorens, Juana

    2012-11-01

    Rhodococcus ruber strain Chol-4 isolated from a sewage sludge sample is able to grow on minimal medium supplemented with steroids, showing a broad catabolic capacity. This paper reports the characterization of three different 3-ketosteroid-Δ(1)-dehydrogenases (KstDs) in the genome of R. ruber strain Chol-4. The genome of this strain does not contain any homologues of a 3-keto-5α-steroid-Δ(4)-dehydrogenase (Kst4d or TesI) that appears in the genomes of Rhodococcus erythropolis SQ1 or Comamonas testosteroni. Growth experiments with kstD2 mutants, either a kstD2 single mutant, kstD2 double mutants in combination with kstD1 or kstD3, or the triple kstD1,2,3 mutant, proved that KstD2 is involved in the transformation of 4-androstene-3,17-dione (AD) to 1,4-androstadiene-3,17-dione (ADD) and in the conversion of 9α-hydroxy-4-androstene-3,17-dione (9OHAD) to 9α-hydroxy-1,4-androstadiene-3,17-dione (9OHADD). kstD2,3 and kstD1,2,3 R. ruber mutants (both lacking KstD2 and KstD3) did not grow in minimal medium with cholesterol as the only carbon source, thus demonstrating the involvement of KstD2 and KstD3 in cholesterol degradation. In contrast, mutation of kstD1 does not alter the bacterial growth on the steroids tested in this study and therefore, the role of this protein still remains unclear. The absence of a functional KstD2 in R. ruber mutants provoked in all cases an accumulation of 9OHAD, as a branch product probably formed by the action of a 3-ketosteroid-9α-hydroxylase (KshAB) on the AD molecule. Therefore, KstD2 is a key enzyme in the AD catabolism pathway of R. ruber strain Chol-4 while KstD3 is involved in cholesterol catabolism. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Triggering the approach of an arene or heteroarene towards an aldehyde via Lewis acid-aldehyde communication.

    PubMed

    Pratihar, Sanjay

    2016-03-14

    The present work reports a combined experimental/computational study of the Lewis acid promoted hydroxyalkylation reaction involving aldehyde and arene/heteroarene and reveals a mechanism in which the rate determining aldehyde to alcohol formation via a four-member cyclic transition state (TS) involves a transfer of hydrogen from arene/heteroarene C-H to aldehyde oxygen with the breaking of the C-H bond and formation of C-C and O-H bonds. The effect of different Sn(iv) derivatives on the hydroxyalkylation reaction from different in situ NMR and computational studies reveals that although the exergonic formation of the intermediate and its gained electrophilicity at the carbonyl carbon drive the reaction in SnCl4 compared to other Sn(iv) derivatives, the overall reaction is low yielding because of its stable intermediate. With respect to different aldehydes, LA promoted hydroxylation was found to be more feasible for an electron withdrawing aldehyde compared to electron rich aldehyde because of lower stability, enhanced electrophilicity gained at the aldehyde center, and a lower activation barrier between its intermediate and TS in the former as compared to the latter. The relative stability of the LA-aldehyde adduct decreases in the order SnCl4 > AlCl3 > InCl3 > BF3 > ZnCl2 > TiCl4 > SiCl4, while the activation barrier (ΔG(#)) between intermediate and transition states increases in the order AlCl3 < SnCl4 < InCl3 < BF3 < TiCl4 < ZnCl2 < SiCl4. On the other hand, the activation barriers in the case of different arenes/heteroarenes are in the order of indole < furan < anisole < thiophene < toluene < benzene < chlorobenzene < cyanobenzene, which suggests a facile reaction in the case of indole and the most difficult reaction in the case of cyanobenzene. The ease of formation of the corresponding diaryl methyl carbocation from the alcohol-LA intermediate is responsible for the determination of the undesired product and is found to be more viable in the case of strong

  9. Thermostable NADP+-Dependent Medium-Chain Alcohol Dehydrogenase from Acinetobacter sp. Strain M-1: Purification and Characterization and Gene Expression in Escherichia coli

    PubMed Central

    Tani, Akio; Sakai, Yasuyoshi; Ishige, Takeru; Kato, Nobuo

    2000-01-01

    NADPH-dependent alkylaldehyde reducing enzyme, which was greatly induced by n-hexadecane, from Acinetobacter sp. strain M-1 was purified and characterized. The purified enzyme had molecular masses of 40 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 160 kDa as determined by gel filtration chromatography. The enzyme, which was shown to be highly thermostable, was most active toward n-heptanal and could use n-alkylaldehydes ranging from C2 to C14 and several substituted benzaldehydes, including the industrially important compounds cinnamyl aldehyde and anisaldehyde, as substrates. The alrA gene coding for this enzyme was cloned, and its nucleotide sequence was determined. The deduced amino acid sequence encoded by the alrA gene exhibited homology to the amino acid sequences of zinc-containing alcohol dehydrogenases from various sources. The gene could be highly expressed in Escherichia coli, and the product was purified to homogeneity by simpler procedures from the recombinant than from the original host. Our results show that this enzyme can be used for industrial bioconversion of useful alcohols and aldehydes. PMID:11097895

  10. Association of Genetically Determined Aldehyde Dehydrogenase 2 Activity with Diabetic Complications in Relation to Alcohol Consumption in Japanese Patients with Type 2 Diabetes Mellitus: The Fukuoka Diabetes Registry

    PubMed Central

    Idewaki, Yasuhiro; Iwase, Masanori; Fujii, Hiroki; Ohkuma, Toshiaki; Ide, Hitoshi; Kaizu, Shinako; Jodai, Tamaki; Kikuchi, Yohei; Hirano, Atsushi; Nakamura, Udai; Kubo, Michiaki; Kitazono, Takanari

    2015-01-01

    Aldehyde dehydrogenase 2 (ALDH2) detoxifies aldehyde produced during ethanol metabolism and oxidative stress. A genetic defect in this enzyme is common in East Asians and determines alcohol consumption behaviors. We investigated the impact of genetically determined ALDH2 activity on diabetic microvascular and macrovascular complications in relation to drinking habits in Japanese patients with type 2 diabetes mellitus. An ALDH2 single-nucleotide polymorphism (rs671) was genotyped in 4,400 patients. Additionally, the relationship of clinical characteristics with ALDH2 activity (ALDH2 *1/*1 active enzyme activity vs. *1/*2 or *2/*2 inactive enzyme activity) and drinking habits (lifetime abstainers vs. former or current drinkers) was investigated cross-sectionally (n = 691 in *1/*1 abstainers, n = 1,315 in abstainers with *2, n = 1,711 in *1/*1 drinkers, n = 683 in drinkers with *2). The multiple logistic regression analysis for diabetic complications was adjusted for age, sex, current smoking habits, leisure-time physical activity, depressive symptoms, diabetes duration, body mass index, hemoglobin A1c, insulin use, high-density lipoprotein cholesterol, systolic blood pressure and renin-angiotensin system inhibitors use. Albuminuria prevalence was significantly lower in the drinkers with *2 than that of other groups (odds ratio [95% confidence interval (CI)]: *1/*1 abstainers as the referent, 0.94 [0.76–1.16] in abstainers with *2, 1.00 [0.80–1.26] in *1/*1 drinkers, 0.71 [0.54–0.93] in drinkers with *2). Retinal photocoagulation prevalence was also lower in drinkers with ALDH2 *2 than that of other groups. In contrast, myocardial infarction was significantly increased in ALDH2 *2 carriers compared with that in ALDH2 *1/*1 abstainers (odds ratio [95% CI]: *1/*1 abstainers as the referent, 2.63 [1.28–6.13] in abstainers with *2, 1.89 [0.89–4.51] in *1/*1 drinkers, 2.35 [1.06–5.79] in drinkers with *2). In summary, patients with type 2 diabetes and ALDH2 *2

  11. Association of Genetically Determined Aldehyde Dehydrogenase 2 Activity with Diabetic Complications in Relation to Alcohol Consumption in Japanese Patients with Type 2 Diabetes Mellitus: The Fukuoka Diabetes Registry.

    PubMed

    Idewaki, Yasuhiro; Iwase, Masanori; Fujii, Hiroki; Ohkuma, Toshiaki; Ide, Hitoshi; Kaizu, Shinako; Jodai, Tamaki; Kikuchi, Yohei; Hirano, Atsushi; Nakamura, Udai; Kubo, Michiaki; Kitazono, Takanari

    2015-01-01

    Aldehyde dehydrogenase 2 (ALDH2) detoxifies aldehyde produced during ethanol metabolism and oxidative stress. A genetic defect in this enzyme is common in East Asians and determines alcohol consumption behaviors. We investigated the impact of genetically determined ALDH2 activity on diabetic microvascular and macrovascular complications in relation to drinking habits in Japanese patients with type 2 diabetes mellitus. An ALDH2 single-nucleotide polymorphism (rs671) was genotyped in 4,400 patients. Additionally, the relationship of clinical characteristics with ALDH2 activity (ALDH2 *1/*1 active enzyme activity vs. *1/*2 or *2/*2 inactive enzyme activity) and drinking habits (lifetime abstainers vs. former or current drinkers) was investigated cross-sectionally (n = 691 in *1/*1 abstainers, n = 1,315 in abstainers with *2, n = 1,711 in *1/*1 drinkers, n = 683 in drinkers with *2). The multiple logistic regression analysis for diabetic complications was adjusted for age, sex, current smoking habits, leisure-time physical activity, depressive symptoms, diabetes duration, body mass index, hemoglobin A1c, insulin use, high-density lipoprotein cholesterol, systolic blood pressure and renin-angiotensin system inhibitors use. Albuminuria prevalence was significantly lower in the drinkers with *2 than that of other groups (odds ratio [95% confidence interval (CI)]: *1/*1 abstainers as the referent, 0.94 [0.76-1.16] in abstainers with *2, 1.00 [0.80-1.26] in *1/*1 drinkers, 0.71 [0.54-0.93] in drinkers with *2). Retinal photocoagulation prevalence was also lower in drinkers with ALDH2 *2 than that of other groups. In contrast, myocardial infarction was significantly increased in ALDH2 *2 carriers compared with that in ALDH2 *1/*1 abstainers (odds ratio [95% CI]: *1/*1 abstainers as the referent, 2.63 [1.28-6.13] in abstainers with *2, 1.89 [0.89-4.51] in *1/*1 drinkers, 2.35 [1.06-5.79] in drinkers with *2). In summary, patients with type 2 diabetes and ALDH2 *2 displayed a

  12. Overexpression of Lactobacillus casei D-hydroxyisocaproic acid dehydrogenase in cheddar cheese.

    PubMed

    Broadbent, Jeffery R; Gummalla, Sanjay; Hughes, Joanne E; Johnson, Mark E; Rankin, Scott A; Drake, Mary Anne

    2004-08-01

    Metabolism of aromatic amino acids by lactic acid bacteria is an important source of off-flavor compounds in Cheddar cheese. Previous work has shown that alpha-keto acids produced from Trp, Tyr, and Phe by aminotransferase enzymes are chemically labile and may degrade spontaneously into a variety of off-flavor compounds. However, dairy lactobacilli can convert unstable alpha-keto acids to more-stable alpha-hydroxy acids via the action of alpha-keto acid dehydrogenases such as d-hydroxyisocaproic acid dehydrogenase. To further characterize the role of this enzyme in cheese flavor, the Lactobacillus casei d-hydroxyisocaproic acid dehydrogenase gene was cloned into the high-copy-number vector pTRKH2 and transformed into L. casei ATCC 334. Enzyme assays confirmed that alpha-keto acid dehydrogenase activity was significantly higher in pTRKH2:dhic transformants than in wild-type cells. Reduced-fat Cheddar cheeses were made with Lactococcus lactis starter only, starter plus L. casei ATCC 334, and starter plus L. casei ATCC 334 transformed with pTRKH2:dhic. After 3 months of aging, the cheese chemistry and flavor attributes were evaluated instrumentally by gas chromatography-mass spectrometry and by descriptive sensory analysis. The culture system used significantly affected the concentrations of various ketones, aldehydes, alcohols, and esters and one sulfur compound in cheese. Results further indicated that enhanced expression of d-hydroxyisocaproic acid dehydrogenase suppressed spontaneous degradation of alpha-keto acids, but sensory work indicated that this effect retarded cheese flavor development.

  13. Enantioselective synthesis of syn/anti-1,3-amino alcohols via proline-catalyzed sequential alpha-aminoxylation/alpha-amination and Horner-Wadsworth-Emmons olefination of aldehydes.

    PubMed

    Jha, Vishwajeet; Kondekar, Nagendra B; Kumar, Pradeep

    2010-06-18

    A novel and general method for asymmetric synthesis of both syn/anti-1,3-amino alcohols is described. The method uses proline-catalyzed sequential alpha-aminoxylation/ alpha-amination and Horner-Wadsworth-Emmons (HWE) olefination of aldehydes as the key step. By using this method, a short synthesis of a bioactive molecule, (R)-1-((S)-1-methylpyrrolidin-2-yl)-5-phenylpentan-2-ol, is also accomplished.

  14. A dual substrate kinetic model for cytochrome P450BM3-F87G catalysis: simultaneous binding of long chain aldehydes and 4-fluorophenol.

    PubMed

    Ledford, Chelsea; McMahon, Monica; Whitesell, Ashley; Khan, Ghalib; Kandagatla, Suneel K; Hurst, Dow P; Reggio, Patricia H; Raner, Gregory M

    2017-02-01

    To develop a model for binding and catalysis associated with the stimulation of 4-fluorophenol (4-FP) oxidation in the presence of long chain aldehydes by the enzymatic catalyst, cytochrome P450 BM3 -F87G. A variation of the Michaeli-Menten kinetic model was employed to describe interactions at the active site of the enzyme, along with computer aided modeling approaches. In addition to the hydroquinone product arising from de-fluorination of 4-FP, a second product (p-fluorocatechol) was also observed and, like the hydroquinone, its rate of formation increased in the presence of the aldehyde. When only aldehyde was present with the enzyme, BM3-F87G catalyzed its oxidation to the corresponding carboxylic acid; however, this activity was inhibited when 4-FP was added to the reaction. A 3D computer model of the active site containing both aldehyde and 4-FP was generated, guided by these kinetic observations. Finally, partitioning between the two phenolic products was examined with an emphasis on the conditions directing the initial epoxidation at either the 2,3- or 3,4-positions on the substrate. Temperature, reaction time, substrate concentration, and the structure of the aldehyde had no substantial effect on the overall product ratios, however the NADPH coupling efficiency decreased when unsaturated aldehydes were included, or when the temperature of the reaction was reduced. The unsaturated aldehyde, trans-2-decenal, stimulates BM3-F87G catalyzed oxidation of 4-fluorophenol through a cooperative active site binding mode that doesn't influence product distributions or coupling efficiencies, while 4-fluorophenol acts as a competitive inhibitor of aldehyde oxidation.

  15. Furaldehyde substrate specificity and kinetics of Saccharomyces cerevisiae alcohol dehydrogenase 1 variants.

    PubMed

    Laadan, Boaz; Wallace-Salinas, Valeria; Carlsson, Åsa Janfalk; Almeida, João Rm; Rådström, Peter; Gorwa-Grauslund, Marie F

    2014-08-09

    A previously discovered mutant of Saccharomyces cerevisiae alcohol dehydrogenase 1 (Adh1p) was shown to enable a unique NADH-dependent reduction of 5-hydroxymethylfurfural (HMF), a well-known inhibitor of yeast fermentation. In the present study, site-directed mutagenesis of both native and mutated ADH1 genes was performed in order to identify the key amino acids involved in this substrate shift, resulting in Adh1p-variants with different substrate specificities. In vitro activities of the Adh1p-variants using two furaldehydes, HMF and furfural, revealed that HMF reduction ability could be acquired after a single amino acid substitution (Y295C). The highest activity, however, was reached with the double mutation S110P Y295C. Kinetic characterization with both aldehydes and the in vivo primary substrate acetaldehyde also enabled to correlate the alterations in substrate affinity with the different amino acid substitutions. We demonstrated the key role of Y295C mutation in HMF reduction by Adh1p. We generated and kinetically characterized a group of protein variants using two furaldehyde compounds of industrial relevance. Also, we showed that there is a threshold after which higher in vitro HMF reduction activities do not correlate any more with faster in vivo rates of HMF conversion, indicating other cell limitations in the conversion of HMF.

  16. Expression and associations of TRAF1, BMI-1, ALDH1, and Lin28B in oral squamous cell carcinoma.

    PubMed

    Wu, Tian-Fu; Li, Yi-Cun; Ma, Si-Rui; Bing-Liu; Zhang, Wen-Feng; Sun, Zhi-Jun

    2017-04-01

    Tumor necrosis factor receptor-associated factor 1, an adaptor protein of tumor necrosis factor 2, is involved in classical nuclear factor (NF)-κB activation and lymphocyte recruitment. However, less is known about the expression and association of tumor necrosis factor receptor-associated factor 1 with cancer stem cell markers in oral squamous cell carcinoma. This study aimed to investigate the expression of tumor necrosis factor receptor-associated factor 1 and stem cell characteristic markers (lin28 homolog B, B cell-specific Moloney murine leukemia virus integration site 1, and aldehyde dehydrogenase 1) in oral squamous cell carcinoma and analyze their relations. Paraffin-embedded tissues of 78 oral squamous cell carcinomas, 39 normal oral mucosa, and 12 oral dysplasia tissues were employed in tissue microarrays, and the expression of tumor necrosis factor receptor-associated factor 1, B cell-specific Moloney murine leukemia virus integration site 1, aldehyde dehydrogenase 1, and lin28 homolog B was measured by immunohistostaining and digital pathological analysis. The expression of tumor necrosis factor receptor-associated factor 1 was higher in the oral squamous cell carcinoma group as compared with the expression in the oral mucosa (p < 0.01) and oral dysplasia (p < 0.001) groups. In addition, the expression of tumor necrosis factor receptor-associated factor 1 was associated with those of B cell-specific Moloney murine leukemia virus integration site 1, aldehyde dehydrogenase 1, and lin28 homolog B (p = 0.032, r 2  = 0.109; p < 0.0001, r 2  = 0.64; and p < 0.001, r 2  = 0.16) in oral squamous cell carcinoma. The patient survival rate was lower in the highly expressed tumor necrosis factor receptor-associated factor 1 group, although the difference was not significant. The clustering analysis showed that tumor necrosis factor receptor-associated factor 1 was most related to aldehyde dehydrogenase 1. These findings suggest

  17. Isolation and characterization of full-length putative alcohol dehydrogenase genes from polygonum minus

    NASA Astrophysics Data System (ADS)

    Hamid, Nur Athirah Abd; Ismail, Ismanizan

    2013-11-01

    Polygonum minus, locally named as Kesum is an aromatic herb which is high in secondary metabolite content. Alcohol dehydrogenase is an important enzyme that catalyzes the reversible oxidation of alcohol and aldehyde with the presence of NAD(P)(H) as co-factor. The main focus of this research is to identify the gene of ADH. The total RNA was extracted from leaves of P. minus which was treated with 150 μM Jasmonic acid. Full-length cDNA sequence of ADH was isolated via rapid amplification cDNA end (RACE). Subsequently, in silico analysis was conducted on the full-length cDNA sequence and PCR was done on genomic DNA to determine the exon and intron organization. Two sequences of ADH, designated as PmADH1 and PmADH2 were successfully isolated. Both sequences have ORF of 801 bp which encode 266 aa residues. Nucleotide sequence comparison of PmADH1 and PmADH2 indicated that both sequences are highly similar at the ORF region but divergent in the 3' untranslated regions (UTR). The amino acid is differ at the 107 residue; PmADH1 contains Gly (G) residue while PmADH2 contains Cys (C) residue. The intron-exon organization pattern of both sequences are also same, with 3 introns and 4 exons. Based on in silico analysis, both sequences contain "classical" short chain alcohol dehydrogenases/reductases ((c) SDRs) conserved domain. The results suggest that both sequences are the members of short chain alcohol dehydrogenase family.

  18. Loss of function of cinnamyl alcohol dehydrogenase 1 leads to unconventional lignin and a temperature-sensitive growth defect in Medicago truncatula.

    PubMed

    Zhao, Qiao; Tobimatsu, Yuki; Zhou, Rui; Pattathil, Sivakumar; Gallego-Giraldo, Lina; Fu, Chunxiang; Jackson, Lisa A; Hahn, Michael G; Kim, Hoon; Chen, Fang; Ralph, John; Dixon, Richard A

    2013-08-13

    There is considerable debate over the capacity of the cell wall polymer lignin to incorporate unnatural monomer units. We have identified Tnt1 retrotransposon insertion mutants of barrel medic (Medicago truncatula) that show reduced lignin autofluorescence under UV microscopy and red coloration in interfascicular fibers. The phenotype is caused by insertion of retrotransposons into a gene annotated as encoding cinnamyl alcohol dehydrogenase, here designated M. truncatula CAD1. NMR analysis indicated that the lignin is derived almost exclusively from coniferaldehyde and sinapaldehyde and is therefore strikingly different from classical lignins, which are derived mainly from coniferyl and sinapyl alcohols. Despite such a major alteration in lignin structure, the plants appear normal under standard conditions in the greenhouse or growth chamber. However, the plants are dwarfed when grown at 30 °C. Glycome profiling revealed an increased extractability of some xylan and pectin epitopes from the cell walls of the cad1-1 mutant but decreased extractability of others, suggesting that aldehyde-dominant lignin significantly alters cell wall structure.

  19. Loss of function of cinnamyl alcohol dehydrogenase 1 leads to unconventional lignin and a temperature-sensitive growth defect in Medicago truncatula

    PubMed Central

    Zhao, Qiao; Tobimatsu, Yuki; Zhou, Rui; Pattathil, Sivakumar; Gallego-Giraldo, Lina; Fu, Chunxiang; Jackson, Lisa A.; Hahn, Michael G.; Kim, Hoon; Chen, Fang; Ralph, John; Dixon, Richard A.

    2013-01-01

    There is considerable debate over the capacity of the cell wall polymer lignin to incorporate unnatural monomer units. We have identified Tnt1 retrotransposon insertion mutants of barrel medic (Medicago truncatula) that show reduced lignin autofluorescence under UV microscopy and red coloration in interfascicular fibers. The phenotype is caused by insertion of retrotransposons into a gene annotated as encoding cinnamyl alcohol dehydrogenase, here designated M. truncatula CAD1. NMR analysis indicated that the lignin is derived almost exclusively from coniferaldehyde and sinapaldehyde and is therefore strikingly different from classical lignins, which are derived mainly from coniferyl and sinapyl alcohols. Despite such a major alteration in lignin structure, the plants appear normal under standard conditions in the greenhouse or growth chamber. However, the plants are dwarfed when grown at 30 °C. Glycome profiling revealed an increased extractability of some xylan and pectin epitopes from the cell walls of the cad1-1 mutant but decreased extractability of others, suggesting that aldehyde-dominant lignin significantly alters cell wall structure. PMID:23901113

  20. Assessment and predictor determination of indoor aldehyde levels in Paris newborn babies' homes.

    PubMed

    Dassonville, C; Demattei, C; Laurent, A-M; Le Moullec, Y; Seta, N; Momas, I

    2009-08-01

    Exposure to indoor chemical air pollutants expected to be potentially involved in allergic respiratory diseases in infants is poorly documented. A specific environmental investigation included in a birth cohort study was carried out to first assess indoor airborne aldehyde levels, using passive devices and their variability within 1 year (1, 6, 9 and 12 months) in the bedroom of 196 Paris infants, and second, to identify predictors for aldehyde concentrations using interviewer administered questionnaires about housing factors. Comfort parameters and carbon dioxide levels were measured simultaneously. Aldehydes were detected in almost all dwellings and geometric mean levels (geometric standard deviation) at the first visit were respectively for formaldehyde, acetaldehyde, hexanal, and pentanal 19.4 (1.7) microg/m(3), 8.9 (1.8) microg/m(3), 25.3 (3.1) microg/m(3), 3.7 (2.3) microg/m(3), consistent with earlier published results. Generalized Estimating Equation multivariate analyses showed that, apart from comfort parameters, aeration and season, the main indoor aldehyde sources were either continuous (building materials and coverings especially when they were new) or discontinuous (smoking, use of air fresheners and cleaning products, DIY etc...). Finally, the data collected by questionnaires should be sufficient to enable us to classify each infant in our cohort study according to his/her degree of exposure to the main aldehydes. This analysis contributed to document indoor aldehyde levels in Parisian homes and to identify factors determining these levels. In the major part of newborn babies' homes, indoor formaldehyde levels were above the guideline value of 10 microg/m(3) proposed by the French Agency for Environmental and Occupational Health Safety for long-term exposure. Given this result, it is essential to study the health impact of exposure to aldehydes especially formaldehyde on the incidence of respiratory and allergic symptoms, particularly during the

  1. Aldehyde dehydrogenase 2 protects human umbilical vein endothelial cells against oxidative damage and increases endothelial nitric oxide production to reverse nitroglycerin tolerance.

    PubMed

    Hu, X Y; Fang, Q; Ma, D; Jiang, L; Yang, Y; Sun, J; Yang, C; Wang, J S

    2016-06-10

    Medical nitroglycerin (glyceryl trinitrate, GTN) use is limited principally by tolerance typified by a decrease in nitric oxide (NO) produced by biotransformation. Such tolerance may lead to endothelial dysfunction by inducing oxidative stress. In vivo studies have demonstrated that aldehyde dehydrogenase 2 (ALDH2) plays important roles in GTN biotransformation and tolerance. Thus, modification of ALDH2 expression represents a potentially effective strategy to prevent and reverse GTN tolerance and endothelial dysfunction. In this study, a eukaryotic expression vector containing the ALDH2 gene was introduced into human umbilical vein endothelial cells (HUVECs) by liposome-mediated transfection. An indirect immunofluorescence assay showed that ALDH2 expression increased 24 h after transfection. Moreover, real-time polymerase chain reaction and western blotting revealed significantly higher ALDH2 mRNA and protein expression in the gene-transfected group than in the two control groups. GTN tolerance was induced by treating HUVECs with 10 mM GTN for 16 h + 10 min, which significantly decreased NO levels in control cells, but not in those transfected with ALDH2. Overexpression of ALDH2 increased cell survival against GTN-induced cytotoxicity and conferred protection from oxidative damage resulting from nitrate tolerance, accompanied by decreased production of intracellular reactive oxygen species and reduced expression of heme oxygenase 1. Furthermore, ALDH2 overexpression promoted Akt phosphorylation under GTN tolerance conditions. ALDH2 gene transfection can reverse and prevent tolerance to GTN through its bioactivation and protect against oxidative damage, preventing the development of endothelial dysfunction.

  2. Substrate specificity and inhibitor sensitivity of rabbit 20α-hydroxysteroid dehydrogenase.

    PubMed

    Endo, Satoshi; Arai, Yuki; Hara, Akira; Kitade, Yukio; Bunai, Yasuo; El-Kabbani, Ossama; Matsunaga, Toshiyuki

    2013-01-01

    In this study, we examined the substrate specificity and inhibitor sensitivity of rabbit 20α-hydroxysteroid dehydrogenase (AKR1C5), which plays a role in the termination of pregnancy by progesterone inactivation. AKR1C5 moderately reduced the 3-keto group of only 5α-dihydrosteroids with 17β- or 20α/β-hydroxy group among 3-ketosteroids. In contrast, the enzyme reversibly and efficiently catalyzed the reduction of various 17- and 20-ketosteroids, including estrogen precursors (dehydroepiandrosterone, estrone and 5α-androstan-3β-ol-17-one) and tocolytic 5β-pregnane-3,20-dione. In addition to the progesterone inactivation, the formation of estrogens and metabolism of the tocolytic steroid by AKR1C5 may be related to its role in rabbit parturition. AKR1C5 also reduced various non-steroidal carbonyl compounds, including isatin, an antagonist of the C-type natriuretic peptide receptor, and 4-oxo-2-nonenal, suggesting its roles in controlling the bioactive isatin and detoxification of cytotoxic aldehydes. AKR1C5 was potently and competitively inhibited by flavonoids such as kaempferol and quercetin, suggesting that its activity is affected by ingested flavonoids.

  3. Immobilisation and characterisation of biocatalytic co-factor recycling enzymes, glucose dehydrogenase and NADH oxidase, on aldehyde functional ReSyn™ polymer microspheres.

    PubMed

    Twala, Busisiwe V; Sewell, B Trevor; Jordaan, Justin

    2012-05-10

    The use of enzymes in industrial applications is limited by their instability, cost and difficulty in their recovery and re-use. Immobilisation is a technique which has been shown to alleviate these limitations in biocatalysis. Here we describe the immobilisation of two biocatalytically relevant co-factor recycling enzymes, glucose dehydrogenase (GDH) and NADH oxidase (NOD) on aldehyde functional ReSyn™ polymer microspheres with varying functional group densities. The successful immobilisation of the enzymes on this new high capacity microsphere technology resulted in the maintenance of activity of ∼40% for GDH and a maximum of 15.4% for NOD. The microsphere variant with highest functional group density of ∼3500 μmol g⁻¹ displayed the highest specific activity for the immobilisation of both enzymes at 33.22 U mg⁻¹ and 6.75 U mg⁻¹ for GDH and NOD with respective loading capacities of 51% (0.51 mg mg⁻¹) and 129% (1.29 mg mg⁻¹). The immobilised GDH further displayed improved activity in the acidic pH range. Both enzymes displayed improved pH and thermal stability with the most pronounced thermal stability for GDH displayed on ReSyn™ A during temperature incubation at 65 °C with a 13.59 fold increase, and NOD with a 2.25-fold improvement at 45 °C on the same microsphere variant. An important finding is the suitability of the microspheres for stabilisation of the multimeric protein GDH. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Two-Carbon Homologation of Ketones to 3-Methyl Unsaturated Aldehydes

    USDA-ARS?s Scientific Manuscript database

    The usual scheme of two-carbon homologation of ketones to 3-methyl unsaturated aldehydes by Horner-Wadsworth-Emmons condensations with phosphonate esters, such as triethyl-2-phosphonoacetate, involves three steps. The phosphonate condensation step results in extension of the carbon chain by two carb...

  5. Selection based on CD133 and high aldehyde dehydrogenase activity isolates long-term reconstituting human hematopoietic stem cells

    PubMed Central

    Hess, David A.; Wirthlin, Louisa; Craft, Timothy P.; Herrbrich, Phillip E.; Hohm, Sarah A.; Lahey, Ryan; Eades, William C.; Creer, Michael H.; Nolta, Jan A.

    2006-01-01

    The development of novel cell-based therapies requires understanding of distinct human hematopoietic stem and progenitor cell populations. We recently isolated reconstituting hematopoietic stem cells (HSCs) by lineage depletion and purification based on high aldehyde dehydrogenase activity (ALDHhiLin- cells). Here, we further dissected the ALDHhi-Lin- population by selection for CD133, a surface molecule expressed on progenitors from hematopoietic, endothelial, and neural lineages. ALDHhiCD133+Lin- cells were primarily CD34+, but also included CD34-CD38-CD133+ cells, a phenotype previously associated with repopulating function. Both ALDHhiCD133-Lin- and ALDHhiCD133+Lin- cells demonstrated distinct clonogenic progenitor function in vitro, whereas only the ALDHhiCD133+Lin- population seeded the murine bone marrow 48 hours after transplantation. Significant human cell repopulation was observed only in NOD/SCID and NOD/SCID β2M-null mice that received transplants of ALDHhiCD133+Lin- cells. Limiting dilution analysis demonstrated a 10-fold increase in the frequency of NOD/SCID repopulating cells compared with CD133+Lin- cells, suggesting that high ALDH activity further purified cells with repopulating function. Transplanted ALDHhiCD133+Lin- cells also maintained primitive hematopoietic phenotypes (CD34+CD38-) and demonstrated enhanced repopulating function in recipients of serial, secondary transplants. Cell selection based on ALDH activity and CD133 expression provides a novel purification of HSCs with long-term repopulating function and may be considered an alternative to CD34 cell selection for stem cell therapies. PMID:16269619

  6. 1,3-Propanediol dehydrogenases in Lactobacillus reuteri: impact on central metabolism and 3-hydroxypropionaldehyde production.

    PubMed

    Stevens, Marc J A; Vollenweider, Sabine; Meile, Leo; Lacroix, Christophe

    2011-08-03

    Lactobacillus reuteri metabolizes glycerol to 3-hydroxypropionaldehyde (3-HPA) and further to 1,3-propanediol (1,3-PDO), the latter step catalysed by a propanediol dehydrogenase (PDH). The last step in this pathway regenerates NAD+ and enables therefore the energetically more favourable production of acetate over ethanol during growth on glucose. A search throughout the genome of L. reuteri DSM 20016 revealed two putative PDHs encoded by ORFs lr_0030 and lr_1734. ORF lr_1734 is situated in the pdu operon encoding the glycerol conversion machinery and therefore likely involved in 1,3-PDO formation. ORF lr_0030 has not been associated with PDH-activity so far. To elucidate the role of these two PDHs, gene deletion mutant strains were constructed. Growth behaviour on glucose was comparable between the wild type and both mutant strains. However, on glucose + glycerol, the exponential growth rate of Δlr_0030 was lower compared to the wild type and the lr_1734 mutant. Furthermore, glycerol addition resulted in decreased ethanol production in the wild type and Δlr_1734, but not in Δlr_0030. PDH activity measurements using 3-HPA as a substrate revealed lower activity of Δlr_0030 extracts from exponential growing cells compared to wild type and Δlr_1734 extracts.During biotechnological 3-HPA production using non-growing cells, the ratio 3-HPA to 1,3-PDO was approximately 7 in the wild type and Δlr_0030, whereas this ratio was 12.5 in the mutant Δlr_1734. The enzyme encoded by lr_0030 plays a pivotal role in 3-HPA conversion in exponential growing L. reuteri cells. The enzyme encoded by lr_1734 is active during 3-HPA production by non-growing cells and this enzyme is a useful target to enhance 3-HPA production and minimize formation of the by-product 1,3-PDO.

  7. Formal [4+2] cycloaddition of di-tert-butyl 2-ethoxycyclobutane-1,1-dicarboxylate with ketones or aldehydes and tandem lactonization.

    PubMed

    Okado, Ryohei; Nowaki, Aya; Matsuo, Jun-Ichi; Ishibashi, Hiroyuki

    2012-01-01

    A catalytic amount of tin(IV) chloride catalyzed formal [4+2] cycloaddition reaction of di-tert-butyl 2-ethoxycyclobutane-1,1-carboxylate with ketones or aldehydes to give diethyl 6-ethoxydihydro-2H-pyran-3,3(4H)-dicarboxylates, whereas two equivalents of trimethylsilyl triflate promoted tandem [4+2] cycloaddition and lactonization to afford 3-oxo-2,6-dioxabicyclo[2.2.2]octane-4-carboxylate esters.

  8. Characterization of an aldolase-dehydrogenase complex from the cholesterol degradation pathway of Mycobacterium tuberculosis.

    PubMed

    Carere, Jason; McKenna, Sarah E; Kimber, Matthew S; Seah, Stephen Y K

    2013-05-21

    HsaF and HsaG are an aldolase and dehydrogenase from the cholesterol degradation pathway of Mycobacterium tuberculosis. HsaF could be heterologously expressed and purified as a soluble dimer, but the enzyme was inactive in the absence of HsaG. HsaF catalyzes the aldol cleavage of 4-hydroxy-2-oxoacids to produce pyruvate and an aldehyde. The enzyme requires divalent metals for activity, with a preference for Mn(2+). The Km values for 4-hydroxy-2-oxoacids were about 20-fold lower than observed for the aldolase homologue, BphI from the polychlorinated biphenyl degradation pathway. Acetaldehyde and propionaldehyde were channeled directly to the dehydrogenase, HsaG, without export to the bulk solvent where they were transformed to acyl-CoA in an NAD(+) and coenzyme A dependent reaction. HsaG is able to utilize aldehydes up to five carbons in length as substrates, with similar catalytic efficiencies. The HsaF-HsaG complex was crystallized and its structure was determined to a resolution of 1.93 Å. Substitution of serine 41 in HsaG with isoleucine or aspartate resulted in about 35-fold increase in Km for CoA but only 4-fold increase in Km dephospho-CoA, suggesting that this residue interacts with the 3'-ribose phosphate of CoA. A second protein annotated as a 4-hydroxy-2-oxopentanoic acid aldolase in M. tuberculosis (MhpE, Rv3469c) was expressed and purified, but was found to lack aldolase activity. Instead this enzyme was found to possess oxaloacetate decarboxylase activity, consistent with the conservation (with the 4-hydroxy-2-oxoacid aldolases) of residues involved in pyruvate enolate stabilization.

  9. Uptake of aldehydes and ketones at typical indoor concentrations by houseplants.

    PubMed

    Tani, Akira; Hewitt, C Nicholas

    2009-11-01

    The uptake rates of low-molecular weight aldehydes and ketones by peace lily (Spathiphyllum clevelandii) and golden pothos (Epipremnum aureum) leaves at typical indoor ambient concentrations (10(1)-10(2) ppbv) were determined. The C3-C6 aldehydes and C4-C6 ketones were taken up by the plant leaves, but the C3 ketone acetone was not. The uptake rate normalized to the ambient concentration C(a) ranged from 7 to 19 mmol m(-2) s(-1) and from 2 to 7 mmol m(-2) s(-1) for the aldehydes and ketones, respectively. Longer-term fumigation results revealed that the total uptake amounts were 30-100 times as much as the amounts dissolved in the leaf, suggesting that volatile organic carbons are metabolized in the leaf and/or translocated through the petiole. The ratio of the intercellular concentration to the external (ambient) concentration (C(i)/C(a)) was significantly lower for most aldehydes than for most ketones. In particular, a linear unsaturated aldehyde, crotonaldehyde, had a C(i)/C(a) ratio of approximately 0, probably because of its highest solubility in water.

  10. Microbial Engineering for Aldehyde Synthesis

    PubMed Central

    Kunjapur, Aditya M.

    2015-01-01

    Aldehydes are a class of chemicals with many industrial uses. Several aldehydes are responsible for flavors and fragrances present in plants, but aldehydes are not known to accumulate in most natural microorganisms. In many cases, microbial production of aldehydes presents an attractive alternative to extraction from plants or chemical synthesis. During the past 2 decades, a variety of aldehyde biosynthetic enzymes have undergone detailed characterization. Although metabolic pathways that result in alcohol synthesis via aldehyde intermediates were long known, only recent investigations in model microbes such as Escherichia coli have succeeded in minimizing the rapid endogenous conversion of aldehydes into their corresponding alcohols. Such efforts have provided a foundation for microbial aldehyde synthesis and broader utilization of aldehydes as intermediates for other synthetically challenging biochemical classes. However, aldehyde toxicity imposes a practical limit on achievable aldehyde titers and remains an issue of academic and commercial interest. In this minireview, we summarize published efforts of microbial engineering for aldehyde synthesis, with an emphasis on de novo synthesis, engineered aldehyde accumulation in E. coli, and the challenge of aldehyde toxicity. PMID:25576610

  11. Toxic Neuronal Death by Glyeraldehyde-3-Phosphate Dehydrogenase and Mitochondria

    DTIC Science & Technology

    2003-08-01

    Neuroreport, 10(5), 1149-1153. Sioud, M., & Jespersen, L. (1996). Enhancement of hammerhead ribozyme catalysis by glyceraldehyde-3-phosphate dehydrogenase...1996) Enhancemen t of hammerhead r ibozyme cata lysis by glycera ldehyde-3- phospha te dehydrogenase. J Mol Biol 257:775–789. Sirover MA (1997) Role of

  12. Sirtuin 3 (SIRT3) Protein Regulates Long-chain Acyl-CoA Dehydrogenase by Deacetylating Conserved Lysines Near the Active Site

    PubMed Central

    Bharathi, Sivakama S.; Zhang, Yuxun; Mohsen, Al-Walid; Uppala, Radha; Balasubramani, Manimalha; Schreiber, Emanuel; Uechi, Guy; Beck, Megan E.; Rardin, Matthew J.; Vockley, Jerry; Verdin, Eric; Gibson, Bradford W.; Hirschey, Matthew D.; Goetzman, Eric S.

    2013-01-01

    Long-chain acyl-CoA dehydrogenase (LCAD) is a key mitochondrial fatty acid oxidation enzyme. We previously demonstrated increased LCAD lysine acetylation in SIRT3 knockout mice concomitant with reduced LCAD activity and reduced fatty acid oxidation. To study the effects of acetylation on LCAD and determine sirtuin 3 (SIRT3) target sites, we chemically acetylated recombinant LCAD. Acetylation impeded substrate binding and reduced catalytic efficiency. Deacetylation with recombinant SIRT3 partially restored activity. Residues Lys-318 and Lys-322 were identified as SIRT3-targeted lysines. Arginine substitutions at Lys-318 and Lys-322 prevented the acetylation-induced activity loss. Lys-318 and Lys-322 flank residues Arg-317 and Phe-320, which are conserved among all acyl-CoA dehydrogenases and coordinate the enzyme-bound FAD cofactor in the active site. We propose that acetylation at Lys-318/Lys-322 causes a conformational change which reduces hydride transfer from substrate to FAD. Medium-chain acyl-CoA dehydrogenase and acyl-CoA dehydrogenase 9, two related enzymes with lysines at positions equivalent to Lys-318/Lys-322, were also efficiently deacetylated by SIRT3 following chemical acetylation. These results suggest that acetylation/deacetylation at Lys-318/Lys-322 is a mode of regulating fatty acid oxidation. The same mechanism may regulate other acyl-CoA dehydrogenases. PMID:24121500

  13. A missense mutation in ALDH1A3 causes isolated microphthalmia/anophthalmia in nine individuals from an inbred Muslim kindred.

    PubMed

    Mory, Adi; Ruiz, Francesc X; Dagan, Efrat; Yakovtseva, Evgenia A; Kurolap, Alina; Parés, Xavier; Farrés, Jaume; Gershoni-Baruch, Ruth

    2014-03-01

    Nine affected individuals with isolated anophthalmia/microphthalmia from a large Muslim-inbred kindred were investigated. Assuming autosomal-recessive mode of inheritance, whole-genome linkage analysis, on DNA samples from four affected individuals, was undertaken. Homozygosity mapping techniques were employed and a 1.5-Mbp region, homozygous in all affected individuals, was delineated. The region contained nine genes, one of which, aldehyde dehydrogenase 1 (ALDH1A3), was a clear candidate. This gene seems to encode a key enzyme in the formation of a retinoic-acid gradient along the dorsoventral axis during an early eye development and the development of the olfactory system. Sanger sequence analysis revealed a missense mutation, causing a substitution of valine (Val) to methionine (Met) at position 71. Analyzing the p.Val71Met missense mutation using standard open access software (MutationTaster online, PolyPhen, SIFT/PROVEAN) predicts this variant to be damaging. Enzymatic activity, studied in vitro, showed no changes between the mutated and the wild-type ALDH1A3 protein.

  14. A missense mutation in ALDH1A3 causes isolated microphthalmia/anophthalmia in nine individuals from an inbred Muslim kindred

    PubMed Central

    Mory, Adi; Ruiz, Francesc X; Dagan, Efrat; Yakovtseva, Evgenia A; Kurolap, Alina; Parés, Xavier; Farrés, Jaume; Gershoni-Baruch, Ruth

    2014-01-01

    Nine affected individuals with isolated anophthalmia/microphthalmia from a large Muslim-inbred kindred were investigated. Assuming autosomal-recessive mode of inheritance, whole-genome linkage analysis, on DNA samples from four affected individuals, was undertaken. Homozygosity mapping techniques were employed and a 1.5-Mbp region, homozygous in all affected individuals, was delineated. The region contained nine genes, one of which, aldehyde dehydrogenase 1 (ALDH1A3), was a clear candidate. This gene seems to encode a key enzyme in the formation of a retinoic-acid gradient along the dorsoventral axis during an early eye development and the development of the olfactory system. Sanger sequence analysis revealed a missense mutation, causing a substitution of valine (Val) to methionine (Met) at position 71. Analyzing the p.Val71Met missense mutation using standard open access software (MutationTaster online, PolyPhen, SIFT/PROVEAN) predicts this variant to be damaging. Enzymatic activity, studied in vitro, showed no changes between the mutated and the wild-type ALDH1A3 protein. PMID:23881059

  15. Bifunctional isocitrate-homoisocitrate dehydrogenase: a missing link in the evolution of beta-decarboxylating dehydrogenase.

    PubMed

    Miyazaki, Kentaro

    2005-05-27

    Beta-decarboxylating dehydrogenases comprise 3-isopropylmalate dehydrogenase, isocitrate dehydrogenase, and homoisocitrate dehydrogenase. They share a high degree of amino acid sequence identity and occupy equivalent positions in the amino acid biosynthetic pathways for leucine, glutamate, and lysine, respectively. Therefore, not only the enzymes but also the whole pathways should have evolved from a common ancestral pathway. In Pyrococcus horikoshii, only one pathway of the three has been identified in the genomic sequence, and PH1722 is the sole beta-decarboxylating dehydrogenase gene. The organism does not require leucine, glutamate, or lysine for growth; the single pathway might play multiple (i.e., ancestral) roles in amino acid biosynthesis. The PH1722 gene was cloned and expressed in Escherichia coli and the substrate specificity of the recombinant enzyme was investigated. It exhibited activities on isocitrate and homoisocitrate at near equal efficiency, but not on 3-isopropylmalate. PH1722 is thus a novel, bifunctional beta-decarboxylating dehydrogenase, which likely plays a dual role in glutamate and lysine biosynthesis in vivo.

  16. Expression pattern, ethanol-metabolizing activities, and cellular localization of alcohol and aldehyde dehydrogenases in human large bowel: association of the functional polymorphisms of ADH and ALDH genes with hemorrhoids and colorectal cancer.

    PubMed

    Chiang, Chien-Ping; Jao, Shu-Wen; Lee, Shiao-Pieng; Chen, Pei-Chi; Chung, Chia-Chi; Lee, Shou-Lun; Nieh, Shin; Yin, Shih-Jiun

    2012-02-01

    Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are principal enzymes responsible for metabolism of ethanol. Functional polymorphisms of ADH1B, ADH1C, and ALDH2 genes occur among racial populations. The goal of this study was to systematically determine the functional expressions and cellular localization of ADHs and ALDHs in human rectal mucosa, the lesions of adenocarcinoma and hemorrhoid, and the genetic association of allelic variations of ADH and ALDH with large bowel disorders. Twenty-one surgical specimens of rectal adenocarcinoma and the adjacent normal mucosa, including 16 paired tissues of rectal tumor, normal mucosae of rectum and sigmoid colon from the same individuals, and 18 surgical mixed hemorrhoid specimens and leukocyte DNA samples from 103 colorectal cancer patients, 67 hemorrhoid patients, and 545 control subjects recruited in previous study, were investigated. The isozyme/allozyme expression patterns of ADH and ALDH were identified by isoelectric focusing and the activities were assayed spectrophotometrically. The protein contents of ADH/ALDH isozymes were determined by immunoblotting using the corresponding purified class-specific antibodies; the cellular activity and protein localizations were detected by immunohistochemistry and histochemistry, respectively. Genotypes of ADH1B, ADH1C, and ALDH2 were determined by polymerase chain reaction-restriction fragment length polymorphisms. At 33mM ethanol, pH 7.5, the activity of ADH1C*1/1 phenotypes exhibited 87% higher than that of the ADH1C*1/*2 phenotypes in normal rectal mucosa. The activity of ALDH2-active phenotypes of rectal mucosa was 33% greater than ALDH2-inactive phenotypes at 200μM acetaldehyde. The protein contents in normal rectal mucosa were in the following order: ADH1>ALDH2>ADH3≈ALDH1A1, whereas those of ADH2, ADH4, and ALDH3A1 were fairly low. Both activity and content of ADH1 were significantly decreased in rectal tumors, whereas the ALDH activity remained

  17. Original 2-(3-Alkoxy-1H-pyrazol-1-yl)azines Inhibitors of Human Dihydroorotate Dehydrogenase (DHODH)

    PubMed Central

    2016-01-01

    Following our discovery of human dihydroorotate dehydrogenase (DHODH) inhibition by 2-(3-alkoxy-1H-pyrazol-1-yl)pyrimidine derivatives as well as 2-(4-benzyl-3-ethoxy-5-methyl-1H-pyrazol-1-yl)-5-methylpyridine, we describe here the syntheses and evaluation of an array of azine-bearing analogues. As in our previous report, the structure–activity study of this series of human DHODH inhibitors was based on a phenotypic assay measuring measles virus replication. Among other inhibitors, this round of syntheses and biological evaluation iteration led to the highly active 5-cyclopropyl-2-(4-(2,6-difluorophenoxy)-3-isopropoxy-5-methyl-1H-pyrazol-1-yl)-3-fluoropyridine. Inhibition of DHODH by this compound was confirmed in an array of in vitro assays, including enzymatic tests and cell-based assays for viral replication and cellular growth. This molecule was found to be more active than the known inhibitors of DHODH, brequinar and teriflunomide, thus opening perspectives for its use as a tool or for the design of an original series of immunosuppressive agent. Moreover, because other series of inhibitors of human DHODH have been found to also affect Plasmodium falciparum DHODH, all the compounds were assayed for their effect on P. falciparum growth. However, the modest in vitro inhibition solely observed for two compounds did not correlate with their inhibition of P. falciparum DHODH. PMID:26079043

  18. The activity of the artemisinic aldehyde Δ11(13) reductase promoter is important for artemisinin yield in different chemotypes of Artemisia annua L.

    PubMed

    Yang, Ke; Monfared, Sajad Rashidi; Monafared, Rashidi Sajad; Wang, Hongzhen; Lundgren, Anneli; Brodelius, Peter E

    2015-07-01

    The artemisinic aldehyde double bond reductase (DBR2) plays an important role in the biosynthesis of the antimalarial artemisinin in Artemisia annua. Artemisinic aldehyde is reduced into dihydroartemisinic aldehyde by DBR2. Artemisinic aldehyde can also be oxidized by amorpha-4,11-diene 12-hydroxylase and/or aldehyde dehydrogenase 1 to artemisinic acid, a precursor of arteannuin B. In order to better understand the effects of DBR2 expression on the flow of artemisinic aldehyde into either artemisinin or arteannuin B, we determined the content of dihydroartemisinic aldehyde, artemisinin, artemisinic acid and arteannuin B content of A. annua varieties sorted into two chemotypes. The high artemisinin producers (HAPs), which includes the '2/39', 'Chongqing' and 'Anamed' varieties, produce more artemisinin than arteannuin B; the low artemisinin producers (LAPs), which include the 'Meise', 'Iran#8', 'Iran#14', 'Iran#24' and 'Iran#47' varieties, produce more arteannuin B than artemisinin. Quantitative PCR showed that the relative expression of DBR2 was significantly higher in the HAP varieties. We cloned and sequenced the promoter of the DBR2 gene from varieties of both the LAP and the HAP groups. There were deletions/insertions in the region just upstream of the ATG start codon in the LAP varities, which might be the reason for the different promoter activities of the HAP and LAP varieties. The relevance of promoter variation, DBR2 expression levels and artemisinin biosynthesis capabilities are discussed and a selection method for HAP varieties with a DNA marker is suggested. Furthermore, putative cis-acting regulatory elements differ between the HAP and LAP varieties.

  19. Aldehyde-containing urea-absorbing polysaccharides

    NASA Technical Reports Server (NTRS)

    Mueller, W. A.; Hsu, G. C.; Marsh, H. E., Jr. (Inventor)

    1977-01-01

    A novel aldehyde containing polymer (ACP) is prepared by reaction of a polysaccharide with periodate to introduce aldehyde groups onto the C2 - C3 carbon atoms. By introduction of ether and ester groups onto the pendant primary hydroxyl solubility characteristics are modified. The ACP is utilized to absorb nitrogen bases such as urea in vitro or in vivo.

  20. Aldehyde Detection in Electronic Cigarette Aerosols

    PubMed Central

    2017-01-01

    Acetaldehyde, acrolein, and formaldehyde are the principal toxic aldehydes present in cigarette smoke and contribute to the risk of cardiovascular disease and noncancerous pulmonary disease. The rapid growth of the use of electronic cigarettes (e-cigarettes) has raised concerns over emissions of these harmful aldehydes. This work determines emissions of these aldehydes in both free and bound (aldehyde–hemiacetal) forms and other carbonyls from the use of e-cigarettes. A novel silicon microreactor with a coating phase of 4-(2-aminooxyethyl)-morpholin-4-ium chloride (AMAH) was used to trap carbonyl compounds in the aerosols of e-cigarettes via oximation reactions. AMAH–aldehyde adducts were measured using gas chromatography–mass spectrometry. 1H nuclear magnetic resonance spectroscopy was used to analyze hemiacetals in the aerosols. These aldehydes were detected in the aerosols of all e-cigarettes. Newer-generation e-cigarette devices generated more aldehydes than the first-generation e-cigarettes because of higher battery power output. Formaldehyde–hemiacetal was detected in the aerosols generated from some e-liquids using the newer e-cigarette devices at a battery power output of 11.7 W and above. The emission of these aldehydes from all e-cigarettes, especially higher levels of aldehydes from the newer-generation e-cigarette devices, indicates the risk of using e-cigarettes. PMID:28393137

  1. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN P-94-1810...

  2. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN P-94-1810...

  3. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN P-94-1810...

  4. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN P-94-1810...

  5. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN P-94-1810...

  6. Molecular Structure and Reactivity in the Pyrolysis of Aldehydes

    NASA Astrophysics Data System (ADS)

    Sias, Eric; Cole, Sarah; Sowards, John; Warner, Brian; Wright, Emily; McCunn, Laura R.

    2016-06-01

    The effect of alkyl chain structure on pyrolysis mechanisms has been investigated in a series of aldehydes. Isovaleraldehyde, CH_3CH(CH_3)CH_2CHO, and pivaldehyde, (CH_3)_3CCHO, were subject to thermal decomposition in a resistively heated SiC tubular reactor at 800-1200 °C. Matrix-isolation FTIR spectroscopy was used to identify pyrolysis products. Carbon monoxide and isobutene were major products from each of the aldehydes, which is consistent with what is known from previous studies of unbranched alkyl-chain aldehydes. Other products observed include vinyl alcohol, propene, acetylene, and ethylene, revealing complexities to be considered in the pyrolysis of large, branched-chain aldehydes.

  7. Genetics Home Reference: long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency

    MedlinePlus

    ... Long chain 3-hydroxyacyl-CoA dehydrogenase deficiency Screening, Technology, and Research in Genetics Virginia Department of Health (PDF) Patient Support and Advocacy Resources (4 links) Children Living with Inherited Metabolic Diseases (CLIMB) Children's Mitochondrial ...

  8. Identification of a canine model of pyruvate dehydrogenase phosphatase 1 deficiency.

    PubMed

    Cameron, Jessie M; Maj, Mary C; Levandovskiy, Valeriy; MacKay, Neviana; Shelton, G Diane; Robinson, Brian H

    2007-01-01

    Exercise intolerance syndromes are well known to be associated with inborn errors of metabolism affecting glycolysis (phosphorylase and phosphofructokinase deficiency) and fatty acid oxidation (palmitoyl carnitine transferase deficiency). We have identified a canine model for profound exercise intolerance caused by a deficit in PDP1 (EC 3.1.3.43), the phosphatase enzyme that activates the pyruvate dehydrogenase complex (PDHc). The Clumber spaniel breed was originated in 1760 by the Duc de Noailles, as a hunting dog with a gentle temperament suitable for the 'elderly gentleman'. Here we report that 20% of the current Clumber and Sussex spaniel population are carriers for a null mutation in PDP1, and that homozygosity produces severe exercise intolerance. Human pyruvate dehydrogenase phosphatase deficiency was recently characterized at the molecular level. However, the nature of the human mutation (loss of a single amino acid altering PDP1 activity) made it impossible to discern the role of the second phosphatase isoform, PDP2, in the deficient phenotype. Here we show that the null mutation in dogs provides a valuable animal model with which to study the effects of dysregulation of the PDHc. Knowledge of the molecular defect has allowed for the institution of a rapid restriction enzyme test for the canine mutation that will allow for selective breeding and has led to a suggested dietary therapy for affected dogs that has proven to be beneficial. Pharmacological and genetic therapies for PDP1 deficiency can now be investigated and the role of PDP2 can be fully characterized.

  9. SIRT3 deacetylates and increases pyruvate dehydrogenase activity in cancer cells.

    PubMed

    Ozden, Ozkan; Park, Seong-Hoon; Wagner, Brett A; Song, Ha Yong; Zhu, Yueming; Vassilopoulos, Athanassios; Jung, Barbara; Buettner, Garry R; Gius, David

    2014-11-01

    Pyruvate dehydrogenase E1α (PDHA1) is the first component enzyme of the pyruvate dehydrogenase (PDH) complex that transforms pyruvate, via pyruvate decarboxylation, into acetyl-CoA that is subsequently used by both the citric acid cycle and oxidative phosphorylation to generate ATP. As such, PDH links glycolysis and oxidative phosphorylation in normal as well as cancer cells. Herein we report that SIRT3 interacts with PDHA1 and directs its enzymatic activity via changes in protein acetylation. SIRT3 deacetylates PDHA1 lysine 321 (K321), and a PDHA1 mutant mimicking a deacetylated lysine (PDHA1(K321R)) increases PDH activity, compared to the K321 acetylation mimic (PDHA1(K321Q)) or wild-type PDHA1. Finally, PDHA1(K321Q) exhibited a more transformed in vitro cellular phenotype compared to PDHA1(K321R). These results suggest that the acetylation of PDHA1 provides another layer of enzymatic regulation, in addition to phosphorylation, involving a reversible acetyllysine, suggesting that the acetylome, as well as the kinome, links glycolysis to respiration. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Subcellular distribution of delta 5-3 beta-hydroxy steroid dehydrogenase in the granulosa cells of the domestic fowl (Gallus domesticus).

    PubMed Central

    Armstrong, D G

    1979-01-01

    1. The distribution of 3 beta-hydroxy steroid dehydrogenase was examined in the subcellular fractions of granulosa cells collected from the ovary of the domestic fowl. 2. 3 beta-hydroxy steroid dehydrogenase activity was observed in the mitochondrial (4000g for 20min) and microsomal (105 000g for 120min) fractions. 3. Approximately three times more 3 beta-hydroxy steroid dehydrogenase activity was associated with the cytochrome oxidase activity (a mitochondrial marker enzyme) in anteovulatory-follicle granulosa cells than with that of the postovulatory follicle. 4. Comparison of the latent properties of mitochondrial 3 beta-hydroxy steroid dehydrogenase with those of cytochrome oxidase and isocitrate dehydrogenase indicated that 3 beta-hydroxy steroid dehydrogenase is located extramitochondrially. 5. This apparent distribution of 3 beta-hydroxy steroid dehydrogenase is explained on the basis that the mitochondrial activity is either an artefact caused by a redistribution in the subcellular location of the enzyme, occurring during homogenization, or by the existence of a functionally heterogeneous endoplasmic reticulum that yields particles of widely differing sedimentation properties. PMID:518548

  11. 2-Piperidino-1,1,2-triphenylethanol: a highly effective catalyst for the enantioselective arylation of aldehydes.

    PubMed

    Fontes, Montserrat; Verdaguer, Xavier; Solà, Lluís; Pericàs, Miquel A; Riera, Antoni

    2004-04-02

    Here we report the use of 2-piperidino-1,2,2-triphenylethanol (5) as an outstanding catalyst for the ligand-catalyzed arylation of aldehydes. The use of 5 and a 2/1 mixture of Et(2)Zn/Ph(2)Zn provided the corresponding chiral diarylcarbinols with enantiomeric excess of up to 99% ee. The effect of temperature on the reaction enantioselectivity was studied and the inversion temperature (T(inv)) was determined to be 10 degrees C for reaction with p-tolylaldehyde. Most remarkably, lowering the amount of catalyst (5) to 0.5 mol % still afforded excellent levels of enantiocontrol (93.7% ee). Kinetics of the catalyzed and uncatalyzed arylation of aldehydes was studied by means of in situ FT-IR. The background uncatalyzed addition rates to p-tolylaldehyde when using pure Ph(2)Zn and Et(2)Zn/Ph(2)Zn (2/1) suggest that in the latter case a mixed zinc species forms (EtPhZn) minimizing the undesired nonselective addition. Formation of EtPhZn was modeled at the DFT calculation level. A four-center TS (TS-V) corresponding to the Et/Ph scrambling was localized along with two dimers (D-IV and D-VI). The model supports the hypothesis that Et/Ph exchange is a kinetically facile process. Gas evolution experiments during the formation of the active catalyst showed that the formation of an active site with a ONZn-Et (10) moiety is kinetically favored over ONZn-Ph (11). Finally, the phenyl transfer to benzaldehyde was modeled at the PM3(tm) level through anti and syn 5/4/4 tricyclic TS structures for both 10 and 11. The model could correctly predict the sense and selectivity of the overall process and predicted that 11 should be more selective than 10.

  12. Organocatalysed asymmetric beta-amination and multicomponent syn-selective diamination of alpha,beta-unsaturated aldehydes.

    PubMed

    Jiang, Hao; Nielsen, Johanne B; Nielsen, Martin; Jørgensen, Karl Anker

    2007-01-01

    An easy and affordable route for obtaining chiral beta-aminated- and alpha,beta-diaminated aldehydes, 1,3-aminoalcohols, and related compounds by using organocatalysis is presented. The chiral secondary amine (S)-2-[bis(3,5-bistrifluoromethylphenyl)trimethylsilanyloxymethyl]pyrrolidine is used as the catalyst to activate alpha,beta-unsaturated aldehydes, which allows succinimide to add in a 1,4-regio- and stereoselective fashion thereby forming N-protected 1,3-aminoaldehydes in good yields and enantioselectivities. This is followed by two easy transformations giving rise to optically active 1,3-aminoalcohols, a common motif in many biologically active compounds, for example, fibrinogen receptor antagonists. Furthermore, optically active alpha,beta-syn-diaminated aldehydes were obtained by the addition of diethyl azodicarboxylate in a one-pot reaction.

  13. Toward aldehyde and alkane production by removing aldehyde reductase activity in Escherichia coli.

    PubMed

    Rodriguez, Gabriel M; Atsumi, Shota

    2014-09-01

    Advances in synthetic biology and metabolic engineering have enabled the construction of novel biological routes to valuable chemicals using suitable microbial hosts. Aldehydes serve as chemical feedstocks in the synthesis of rubbers, plastics, and other larger molecules. Microbial production of alkanes is dependent on the formation of a fatty aldehyde intermediate which is converted to an alkane by an aldehyde deformylating oxygenase (ADO). However, microbial hosts such as Escherichia coli are plagued by many highly active endogenous aldehyde reductases (ALRs) that convert aldehydes to alcohols, which greatly complicates strain engineering for aldehyde and alkane production. It has been shown that the endogenous ALR activity outcompetes the ADO enzyme for fatty aldehyde substrate. The large degree of ALR redundancy coupled with an incomplete database of ALRs represents a significant obstacle in engineering E. coli for either aldehyde or alkane production. In this study, we identified 44 ALR candidates encoded in the E. coli genome using bioinformatics tools, and undertook a comprehensive screening by measuring the ability of these enzymes to produce isobutanol. From the pool of 44 candidates, we found five new ALRs using this screening method (YahK, DkgA, GldA, YbbO, and YghA). Combined deletions of all 13 known ALRs resulted in a 90-99% reduction in endogenous ALR activity for a wide range of aldehyde substrates (C2-C12). Elucidation of the ALRs found in E. coli could guide one in reducing competing alcohol formation during alkane or aldehyde production. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  14. 17β-Hydroxysteroid dehydrogenase 3 deficiency: Three case reports and a systematic review.

    PubMed

    Yang, Zuwei; Ye, Lei; Wang, Wei; Zhao, Yu; Wang, Wencui; Jia, Huiying; Dong, Zhiya; Chen, Yuhong; Wang, Weiqing; Ning, Guang; Sun, Shouyue

    2017-11-01

    17β-Hydroxysteroid dehydrogenase 3 deficiency is a rare autosomal recessive cause of 46, XY disorders of sex development resulting from HSD17B3 gene mutations, however, no case has been reported in East Asia. The aim of this study was to report three Chinese 46, XY females with 17β-HSD3 deficiency in a single center and perform a systematic review of the literature. Clinical examination, endocrine evaluation and HSD17B3 gene sequencing were performed in the three Chinese phenotypically females (two sisters and one unrelated patient). Relevant articles were searched by using the term "HSD17B3" OR "17beta-HSD3 gene" with restrictions on language (English) and species (human) in Pubmed and Embase. All the three phenotypically female subjects showed 46, XY karyotype, inguinal masses, decreased testosterone and increased androstenedione. Two novel homozygous mutations (W284X and c.124_127delTCTT) in HSD17B3 gene were identified. A systematic review found a total of 121 pedigrees/158 patients, with 78.5% (124/158) of patients assigned as females, 15.2% (24/158) from females to males, and 5.1% (8/158) raised as males. The most common mutation was c.277+4C>T (allele frequency: 25/72) for patients from Europe, and R80Q (allele frequency: 21/54) for patients from West Asia. The testicular histology showed normal infantile testicular tissue in 100% (9/9) infantile patients, normal quantity germ cells in 44.4% (8/18) prepubertal patients and 19.0% (4/21) pubertal and adult patients. We reported the first East Asian 17β-hydroxysteroid dehydrogenase 3 deficiency cases. Additional literature reviews found founder effects among patients with different ethnic background and early orchiopexy may benefit fertility in patients assigned as males. These findings may significantly expand the clinical, ethnic and genetic spectrum of 17β-hydroxysteroid dehydrogenase 3 deficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Structure and regulation of KGD1, the structural gene for yeast alpha-ketoglutarate dehydrogenase.

    PubMed

    Repetto, B; Tzagoloff, A

    1989-06-01

    Nuclear respiratory-defective mutants of Saccharomyces cerevisiae have been screened for lesions in the mitochondrial alpha-ketoglutarate dehydrogenase complex. Strains assigned to complementation group G70 were ascertained to be deficient in enzyme activity due to mutations in the KGD1 gene coding for the alpha-ketoglutarate dehydrogenase component of the complex. The KGD1 gene has been cloned by transformation of a representative kgd1 mutant, C225/U1, with a recombinant plasmid library of wild-type yeast nuclear DNA. Transformants containing the gene on a multicopy plasmid had three- to four-times-higher alpha-ketoglutarate dehydrogenase activity than did wild-type S. cerevisiae. Substitution of the chromosomal copy of KGD1 with a disrupted allele (kgd1::URA3) induced a deficiency in alpha-ketoglutarate dehydrogenase. The sequence of the cloned region of DNA which complements kgd1 mutants was found to have an open reading frame of 3,042 nucleotides capable of coding for a protein of Mw 114,470. The encoded protein had 38% identical residues with the reported sequence of alpha-ketoglutarate dehydrogenase from Escherichia coli. Two lines of evidence indicated that transcription of KGD1 is catabolite repressed. Higher steady-state levels of KGD1 mRNA were detected in wild-type yeast grown on the nonrepressible sugar galactose than in yeast grown on high glucose. Regulation of KGD1 was also studied by fusing different 5'-flanking regions of KGD1 to the lacZ gene of E. coli and measuring the expression of beta-galactosidase in yeast. Transformants harboring a fusion of 693 nucleotides of the 5'-flanking sequence expressed 10 times more beta-galactosidase activity when grown under derepressed conditions. The response to the carbon source was reduced dramatically when the same lacZ fusion was present in a hap2 or hap3 mutant. The promoter element(s) responsible for the regulated expression of KGD1 has been mapped to the -354 to -143 region. This region contained several

  16. Elucidation of the Mechanisms and Environmental Relevance of cis-Dichloroethene and Vinyl Chloride Biodegradation

    DTIC Science & Technology

    2012-11-01

    in iTRAQ study Table 3-12: Ratio of aldehyde and alcohol dehydrogenases from iTRAQ study Table 3-13: Proteins involved in proposed glyoxal...pathway for cDCE degradation proceeds through chloro-, or dichloroacetaldehyde. Multiple aldehyde dehydrogenases are annotated in the genome of...dichloroacetaldehyde is a fortuitous reaction. However, if the initial reaction is monooxygenation to an aldehyde then the true intermediate would be

  17. Elucidation of the Mechanisms and Environmental Relevance of cis-Dichloroethene and Vinyl Chloride Biodegradation

    DTIC Science & Technology

    2012-11-01

    iTRAQ study Table 3-12: Ratio of aldehyde and alcohol dehydrogenases from iTRAQ study Table 3-13: Proteins involved in proposed glyoxal transformation...pathway for cDCE degradation proceeds through chloro-, or dichloroacetaldehyde. Multiple aldehyde dehydrogenases are annotated in the genome of JS666...is a fortuitous reaction. However, if the initial reaction is monooxygenation to an aldehyde then the true intermediate would be

  18. A Pauson-Khand-type reaction between alkynes and olefinic aldehydes catalyzed by rhodium/cobalt heterobimetallic nanoparticles: an olefinic aldehyde as an olefin and CO source.

    PubMed

    Park, Kang Hyun; Jung, Il Gu; Chung, Young Keun

    2004-04-01

    Co/Rh (Co:Rh = 2:2) heterobimetallic nanoparticles derived from Co(2)Rh(2)(CO)(12) react with alkynes and alpha,beta-unsaturated aldehydes such as acrolein, crotonaldehyde, and cinnamic aldehyde and release products resulting from [2 + 2 + 1]cycloaddition of alkyne, carbon monoxide, and alkene. alpha,beta-Unsaturated aldehydes act as a CO and alkene source. These reactions produce 2-substituted cyclopentenones.

  19. Molecular Mechanisms of Aldehyde Toxicity: A Chemical Perspective

    PubMed Central

    2015-01-01

    Aldehydes are electrophilic compounds to which humans are pervasively exposed. Despite a significant health risk due to exposure, the mechanisms of aldehyde toxicity are poorly understood. This ambiguity is likely due to the structural diversity of aldehyde derivatives and corresponding differences in chemical reactions and biological targets. To gain mechanistic insight, we have used parameters based on the hard and soft, acids and bases (HSAB) theory to profile the different aldehyde subclasses with respect to electronic character (softness, hardness), electrophilic reactivity (electrophilic index), and biological nucleophilic targets. Our analyses indicate that short chain aldehydes and longer chain saturated alkanals are hard electrophiles that cause toxicity by forming adducts with hard biological nucleophiles, e.g., primary nitrogen groups on lysine residues. In contrast, α,β-unsaturated carbonyl derivatives, alkenals, and the α-oxoaldehydes are soft electrophiles that preferentially react with soft nucleophilic thiolate groups on cysteine residues. The aldehydes can therefore be grouped into subclasses according to common electronic characteristics (softness/hardness) and molecular mechanisms of toxicity. As we will discuss, the toxic potencies of these subgroups are generally related to corresponding electrophilicities. For some aldehydes, however, predictions of toxicity based on electrophilicity are less accurate due to inherent physicochemical variables that limit target accessibility, e.g., steric hindrance and solubility. The unsaturated aldehydes are also members of the conjugated type-2 alkene chemical class that includes α,β-unsaturated amide, ketone, and ester derivatives. Type-2 alkenes are electrophiles of varying softness and electrophilicity that share a common mechanism of toxicity. Therefore, exposure to an environmental mixture of unsaturated carbonyl derivatives could cause “type-2 alkene toxicity” through additive interactions

  20. Nitrite reductase activity of rat and human xanthine oxidase, xanthine dehydrogenase, and aldehyde oxidase: evaluation of their contribution to NO formation in vivo.

    PubMed

    Maia, Luisa B; Pereira, Vânia; Mira, Lurdes; Moura, José J G

    2015-01-27

    Nitrite is presently considered a NO "storage form" that can be made available, through its one-electron reduction, to maintain NO formation under hypoxia/anoxia. The molybdoenzymes xanthine oxidase/dehydrogenase (XO/XD) and aldehyde oxidase (AO) are two of the most promising mammalian nitrite reductases, and in this work, we characterized NO formation by rat and human XO/XD and AO. This is the first characterization of human enzymes, and our results support the employment of rat liver enzymes as suitable models of the human counterparts. A comprehensive kinetic characterization of the effect of pH on XO and AO-catalyzed nitrite reduction showed that the enzyme's specificity constant for nitrite increase 8-fold, while the Km(NO2(-)) decrease 6-fold, when the pH decreases from 7.4 to 6.3. These results demonstrate that the ability of XO/AO to trigger NO formation would be greatly enhanced under the acidic conditions characteristic of ischemia. The dioxygen inhibition was quantified, and the Ki(O2) values found (24.3-48.8 μM) suggest that in vivo NO formation would be fine-tuned by dioxygen availability. The potential in vivo relative physiological relevance of XO/XD/AO-dependent pathways of NO formation was evaluated using HepG2 and HMEC cell lines subjected to hypoxia. NO formation by the cells was found to be pH-, nitrite-, and dioxygen-dependent, and the relative contribution of XO/XD plus AO was found to be as high as 50%. Collectively, our results supported the possibility that XO/XD and AO can contribute to NO generation under hypoxia inside a living human cell. Furthermore, the molecular mechanism of XO/AO-catalyzed nitrite reduction was revised.

  1. Theoretical study of the reaction mechanism and kinetics of low-molecular-weight atmospheric aldehydes (C1-C4) with NO2

    NASA Astrophysics Data System (ADS)

    Ji, Yuemeng; Gao, Yanpeng; Li, Guiying; An, Taicheng

    2012-07-01

    Accurate description of atmospheric reactions of a series of low-molecular-weight (LMW) aldehydes (C1-C4) with NO2 has been modeled using a direct dynamic approach. The profiles of the potential energy surface were constructed at the BMC-CCSD//MPWB1K/6-311G(d,p) level of theory, and two different pathways have been found: H-abstraction and NO2-addition. The modeling results found that the contribution of NO2-addition reaction pathway to the total rate constant is very small and thus this kind of pathway is insignificant in atmospheric conditions. The predicted H-abstraction products are mainly reactive acyl radical and nitrous acid (HONO) which is very mutagenic and carcinogenic pollutant as well as the precursor of acid deposition. The rate constants of both pathways were also deduced by using canonical variational transition state theory incorporating with the small curvature tunneling correction within 200-360 and 360-2000 K. Theoretical overall rate constants are in good agreement with the available experimental values, whose increase in the order of kformaldehyde < kacetaldehyde < kpropanal < kbutanal, implying that relative long-chain LMW aldehydes are more reactive toward NO2 than those short-chain LMW aldehydes in the atmospheric condition. At 298 K, the total rate constants of LMW aldehydes (C1-C4) with NO2 are obtained as 1.65 × 10-25, 1.43 × 10-24, 3.39 × 10-24 and 1.83 × 10-23 cm3 molecule-1 s-1, respectively.

  2. Mechanistic Insights from Reaction of α-Oxiranyl-Aldehydes with Cyanobacterial Aldehyde Deformylating Oxygenase

    PubMed Central

    Das, Debasis; Ellington, Benjamin; Paul, Bishwajit; Marsh, E. Neil G.

    2014-01-01

    The biosynthesis of long-chain aliphatic hydrocarbons, which are derived from fatty acids, is widespread in Nature. The last step in this pathway involves the decarbonylation of fatty aldehydes to the corresponding alkanes or alkenes. In cyanobacteria this is catalyzed by an aldehyde deformylating oxygenase. We have investigated the mechanism of this enzyme using substrates bearing an oxirane ring adjacent to the aldehyde carbon. The enzyme catalyzed the deformylation of these substrates to produce the corresponding oxiranes. Performing the reaction in D2O allowed the facial selectivity of proton addition to be examined by 1H-NMR spectroscopy. The proton is delivered with equal probability to either face of the oxirane ring, indicating the formation of an oxiranyl radical intermediate that is free to rotate during the reaction. Unexpectedly, the enzyme also catalyzes a side reaction in which oxiranyl-aldehydes undergo tandem deformylation to furnish alkanes two carbons shorter. We present evidence that this involves the rearrangement of the intermediate oxiranyl radical formed in the first step, resulting an aldehyde that is further deformylated in a second step. These observations provide support for a radical mechanism for deformylation and, furthermore, allow the lifetime of the radical intermediate to be estimated based on prior measurements of rate constants for the rearrangement of oxiranyl radicals. PMID:24313866

  3. Fermentation of 1,2-Propanediol and 1,2-Ethanediol by Some Genera of Enterobacteriaceae, Involving Coenzyme B12-Dependent Diol Dehydratase

    PubMed Central

    Toraya, Tetsuo; Honda, Susumu; Fukui, Saburo

    1979-01-01

    Klebsiella pneumoniae (Aerobacter aerogenes) ATCC 8724 was able to grow anaerobically on 1,2-propanediol and 1,2-ethanediol as carbon and energy sources. Whole cells of the bacterium grown anaerobically on 1,2-propanediol or on glycerol catalyzed conversion of 1,2-diols and aldehydes to the corresponding acids and alcohols. Glucose-grown cells also converted aldehydes, but not 1,2-diols, to acids and alcohols. The presence of activities of coenzyme B12-dependent diol dehydratase, alcohol dehydrogenase, coenzyme-A-dependent aldehyde dehydrogenase, phosphotransacetylase, and acetate kinase was demonstrated with crude extracts of 1,2-propanediol-grown cells. The dependence of the levels of these enzymes on growth substrates, together with cofactor requirements in in vitro conversion of these substrates, indicates that 1,2-diols are fermented to the corresponding acids and alcohols via aldehydes, acyl-coenzyme A, and acyl phosphates. This metabolic pathway for 1,2-diol fermentation was also suggested in some other genera of Enterobacteriaceae which were able to grow anaerobically on 1,2-propanediol. When the bacteria were cultivated in a 1,2-propanediol medium not supplemented with cobalt ion, the coenzyme B12-dependent conversion of 1,2-diols to aldehydes was the rate-limiting step in this fermentation. This was because the intracellular concentration of coenzyme B12 was very low in the cells grown in cobalt-deficient medium, since the apoprotein of diol dehydratase was markedly induced in the cells grown in the 1,2-propanediol medium. Better cell yields were obtained when the bacteria were grown anaerobically on 1,2-propanediol. Evidence is presented that aerobically grown cells have a different metabolic pathway for utilizing 1,2-propanediol. PMID:378959

  4. Selective Radical Amination of Aldehydic C(sp2)-H Bonds with Fluoroaryl Azides via Co(II)-Based Metalloradical Catalysis: Synthesis of N-Fluoroaryl Amides from Aldehydes under Neutral and Nonoxidative Conditions.

    PubMed

    Jin, Li-Mei; Lu, Hongjian; Cui, Yuan; Lizardi, Christopher L; Arzua, Thiago N; Wojtas, Lukasz; Cui, Xin; Zhang, X Peter

    2014-06-01

    The Co(II) complex of the D 2h -symmetric amidoporphyrin 3,5-Di t Bu-IbuPhyrin, [Co( P1 )], has proven to be an effective metalloradical catalyst for intermolecular amination of C(sp 2 )-H bonds of aldehydes with fluoroaryl azides. The [Co( P1 )]-catalyzed process can employ aldehydes as the limiting reagents and operate under neutral and non-oxidative conditions, generating nitrogen gas as the only byproduct. The metalloradical aldehydic C-H amination is suitable for different combinations of aldehydes and fluoroaryl azides, producing the corresponding N -fluoroaryl amides in good to excellent yields. A series of mechanistic studies support a stepwise radical mechanism for the Co(II)-catalyzed intermolecular C-H amination.

  5. [Pollution Characteristics of Aldehydes and Ketones Compounds in the Exhaust of Beijing Typical Restaurants].

    PubMed

    Cheng, Jing-chen; Cui, Tong; He, Wan-qing; Nie, Lei; Wang, Jun-ling; Pan, Tao

    2015-08-01

    Aldehydes and ketones compounds, as one of the components in the exhaust of restaurants, are a class of volatile organic compounds (VOCs) with strong chemical reactivity. However, there is no systematic study on aldehydes and ketones compounds in the exhaust of restaurants. To further clarify the food source emission levels of aldehydes and ketones compounds and controlling measures, to access city group catering VOCs emissions control decision-making basis, this study selected 8 Beijing restaurants with different types. The aldehydes and ketones compounds were sampled using DNPH-silica tube, and then ultra performance liquid chromatography was used for quantitative measurement. The aldehydes and ketones concentrations of reference volume condition from 8 restaurants in descending order were Roasted Duck restaurant, Chinese Style Barbecue, Home Dishes, Western Fast-food, School Canteen, Chinese Style Fast-food, Sichuan Cuisine, Huaiyang Cuisine. The results showed that the range of aldehydes and ketones compounds (C1-C9) concentrations of reference volume condition in the exhaust of restaurants was 115.47-1035.99 microg x m(-3). The composition of aldehydes and ketones compounds in the exhaust of sampled restaurants was obviously different. The percentages of C1-C3 were above 40% in the exhaust from Chinese style restaurants. Fast food might emit more C4-C9 aldehydes and ketones compounds. From the current situation of existing aldehydes and ketones compounds control, the removal efficiency of high voltage electrostatic purifiers widely used in Beijing is limited.

  6. Glutamate Dehydrogenase from Apodachlya (Oomycetes) 1

    PubMed Central

    Price, Jeffrey S.; Gleason, Frank H.

    1972-01-01

    A glutamate dehydrogenase specific for nicotinamide-adenine-dinucleotide has been purified 50-fold from Apodachlya brachynema (Leptomitales). Certain physical, chemical, and kinetic properties of this enzyme have been studied, particularly specificity for coenzymes and substrates. With glucose as the sole carbon source, the synthesis of glutamate dehydrogenase was repressed, whereas glutamate, proline, alanine, or ornithine plus aspartate as sole carbon sources induced synthesis of the enzyme. These data indicate that the function of this enzyme is primarily degradative, although there is no evidence for a nicotinamide-adenine-dinucleotide-phosphate-specific biosynthetic glutamate dehydrogenase in Apodachlya. PMID:16657902

  7. Diastereoselective synthesis of chiral 1,3-cyclohexadienals

    PubMed Central

    de la Granja, Ángela P.; Capitán, M. Carmen; Moro, R. F.; Marcos, Isidro S.; Garrido, Narciso M.; Sanz, Francisca; Calle, Emilio

    2018-01-01

    A novel approach to the production of chiral 1,3-cyclohexadienals has been developed. The organocatalysed asymmetric reaction of different β-disubstituted-α,β-unsaturated aldehydes with a chiral α,β-unsaturated aldehyde in the presence of a Jørgensen-Hayashi organocatalyst provides easy and stereocontrolled access to the cyclohexadienal backbone. This method allows for the synthesis of potential photoprotective chiral 1,3-cyclohexadienals and extra extended conjugation compounds in a simple manner. PMID:29438416

  8. Diastereoselective synthesis of chiral 1,3-cyclohexadienals.

    PubMed

    Urosa, Aitor; Tobal, Ignacio E; de la Granja, Ángela P; Capitán, M Carmen; Moro, R F; Marcos, Isidro S; Garrido, Narciso M; Sanz, Francisca; Calle, Emilio; Díez, David

    2018-01-01

    A novel approach to the production of chiral 1,3-cyclohexadienals has been developed. The organocatalysed asymmetric reaction of different β-disubstituted-α,β-unsaturated aldehydes with a chiral α,β-unsaturated aldehyde in the presence of a Jørgensen-Hayashi organocatalyst provides easy and stereocontrolled access to the cyclohexadienal backbone. This method allows for the synthesis of potential photoprotective chiral 1,3-cyclohexadienals and extra extended conjugation compounds in a simple manner.

  9. Aldehydes in Relation to Air Pollution Sources: A Case Study around the Beijing Olympics

    PubMed Central

    Altemose, Brent; Gong, Jicheng; Zhu, Tong; Hu, Min; Zhang, Liwen; Cheng, Hong; Zhang, Lin; Tong, Jian; Kipen, Howard M.; Strickland, Pamela Ohman; Meng, Qingyu; Robson, Mark G.; Zhang, Junfeng

    2015-01-01

    This study was carried out to characterize three aldehydes of health concern (formaldehyde, acetaldehyde, and acrolein) at a central Beijing site in the summer and early fall of 2008 (from June to October). Aldehydes in polluted atmospheres come from both primary and secondary sources, which limits the control strategies for these reactive compounds. Measurements were made before, during, and after the Beijing Olympics to examine whether the dramatic air pollution control measures implemented during the Olympics had an impact on concentrations of the three aldehydes and their underlying primary and secondary sources. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.3±15.1 μg/m3, 27.1±15.7 μg/m3 and 2.3±1.0 μg/m3, respectively, for the entire period of measurements, all being at the high end of concentration ranges measured in cities around the world in photochemical smog seasons. Formaldehyde and acrolein increased during the pollution control period compared to the pre-Olympic Games, followed the changing pattern of temperature, and were significantly correlated with ozone and with a secondary formation factor identified by principal component analysis (PCA). In contrast, acetaldehyde had a reduction in mean concentration during the Olympic air pollution control period compared to the pre-Olympic period and was significantly correlated with several pollutants emitted from local emission sources (e.g., NO2, CO, and PM2.5). Acetaldehyde was also more strongly associated with primary emission sources including vegetative burning and oil combustion factors identified through the PCA. All three aldehydes were lower during the post-Olympic sampling period compared to the before and during Olympic periods, likely due to seasonal and regional effects. Our findings point to the complexity of source control strategies for secondary pollutants. PMID:25883528

  10. The color expression of copigmentation between malvidin-3-O-glucoside and three phenolic aldehydes in model solutions: The effects of pH and molar ratio.

    PubMed

    Zhang, Bo; He, Fei; Zhou, Pan-Pan; Liu, Yue; Duan, Chang-Qing

    2016-05-15

    Copigmentation was investigated in model solutions between the anthocyanin malvidin-3-O-glucoside and three phenolic aldehydes (vanillic, syringic and coniferyl aldehydes) as a function of the pH and the pigment/copigment molar ratio. Tristimulus colorimetry was applied to evaluate the chromatic variations induced by copigmentation process. The results indicated that the greatest magnitude of copigmentation was obtained at pH 3.0 and molar ratio of 1:100, being significantly higher with coniferyl aldehyde, followed by syringic and vanillic aldehydes. The equilibrium constant (K) and Gibbs free energies (ΔG°) determined here show a spontaneous exothermic reaction. Theoretical calculations (ΔGbinding, ΔE) specified the relative arrangement of the pigment and copigment molecules within the complexes. In addition, an atoms in molecules (AIM) analysis was used to explore the main driving forces contributing to the formation of copigmentation complexes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Single marker identification of head and neck squamous cell carcinoma cancer stem cells with aldehyde dehyrdrogenase

    PubMed Central

    Clay, MR.; Tabor, M.; Owen, J.; Carey, TE.; Bradford, CR.; Wolf, GT.; Wicha, MS.; Prince, ME.

    2010-01-01

    Background According to the cancer stem cell (CSC) theory only a small subset of cancer cells are capable of forming tumors. We previously reported that CD44 isolates tumorigenic cells from HNSCC. Recent studies indicate that aldehyde dehydrogenase (ALDH) activity may represent a more specific marker of CSCs. Methods Six primary HNSCC were collected. Cells with high and low ALDH activity (ALDHhigh/ALDHlow) were isolated. ALDHhigh and ALDHlow populations were implanted into NOD/SCID mice and monitored for tumor development. Results ALDHhigh cells represented a small percentage of the tumor cells (1-7.8%). ALDHhigh cells formed tumors from as few as 500 cells in 24/45 implantations while only 3/37 implantations of ALDHlow cells formed tumors. Conclusions ALDHhigh cells comprise a subpopulation cells in HNSCC that are tumorigenic and capable of producing tumors at very low numbers. This finding indicates that ALDH activity on its own is a highly selective marker for CSCs in HNSCC. PMID:20073073

  12. One-Pot Amide Bond Formation from Aldehydes and Amines via a Photoorganocatalytic Activation of Aldehydes.

    PubMed

    Papadopoulos, Giorgos N; Kokotos, Christoforos G

    2016-08-19

    A mild, one-pot, and environmentally friendly synthesis of amides from aldehydes and amines is described. Initially, a photoorganocatalytic reaction of aldehydes with di-isopropyl azodicarboxylate leads to an intermediate carbonyl imide, which can react with a variety of amines to afford the desired amides. The initial visible light-mediated activation of a variety of monosubstituted or disubstituted aldehydes is usually fast, occurring in a few hours. Following the photocatalytic reaction, addition of the primary amine at room temperature or the secondary amine at elevated temperatures leads to the corresponding amide from moderate to excellent yields without epimerization. This methodology was applied in the synthesis of Moclobemide, a drug against depression and social anxiety.

  13. Initial steps of the peroxidase-catalyzed polymerization of coniferyl alcohol and/or sinapyl aldehyde: capillary zone electrophoresis study of pH effect.

    PubMed

    Fournand, David; Cathala, Bernard; Lapierre, Catherine

    2003-01-01

    Capillary zone electrophoresis has been used to monitor the first steps of the dehydrogenative polymerization of coniferyl alcohol, sinapyl aldehyde, or a mixture of both, catalyzed by the horseradish peroxidase (HRP)-H(2)O(2) system. When coniferyl alcohol was the unique HRP substrate, three major dimers were observed (beta-5, beta-beta, and beta-O-4 interunit linkages) and their initial formation velocity as well as their relative abundance varied with pH. The beta-O-4 interunit linkage was thus slightly favored at lower pH values. In contrast, sinapyl aldehyde turned out to be a very poor substrate for HRP except in basic conditions (pH 8). The major dimer observed was the beta,beta'-di-sinapyl aldehyde, a red-brown exhibiting compound which might partly participate in the red coloration usually observed in cinnamyl alcohol dehydrogenase-deficient angiosperms. Finally, when a mixture of coniferyl alcohol and sinapyl aldehyde was used, it looked as if sinapyl aldehyde became a very good substrate for HRP. Indeed, coniferyl alcohol turned out to serve as a redox mediator (i.e. "shuttle oxidant") for the sinapyl aldehyde incorporation in the lignin-like polymer. This means that in particular conditions the specificity of oxidative enzymes might not hinder the incorporation of poor substrates into the growing lignin polymer.

  14. syn-Selective crotylation of aldehydes using bismuth-crotyl bromide-(1-butyl-3-methylimidazolium bromide) combination: some synthetic applications.

    PubMed

    Goswami, Dibakar; Koli, Mrunesh R; Chatterjee, Sucheta; Chattopadhyay, Subrata; Sharma, Anubha

    2017-05-03

    The Bi-[bmim][Br] combination has been found to offer high syn-selectivity in the crotylation of aldehydes with crotyl bromide using practically stoichiometric amounts of the reagents. The room temperature ionic liquid (RTIL), [bmim][Br], activated Bi metal in the presence of oxygen to produce crotylbismuthdibromide, which reacted with the aldehydes at room temperature. The major anti-syn diastereomeric product obtained from the crotylation of (R)-cyclohexylideneglyceraldehyde was utilized for the synthesis of dictyostatin and cryptophycin segments, and (+)-cis-aerangis lactone, using standard synthetic protocols.

  15. Selective Radical Amination of Aldehydic C(sp2)–H Bonds with Fluoroaryl Azides via Co(II)-Based Metalloradical Catalysis: Synthesis of N-Fluoroaryl Amides from Aldehydes under Neutral and Nonoxidative Conditions

    PubMed Central

    Jin, Li-Mei; Lu, Hongjian; Cui, Yuan; Lizardi, Christopher L.; Arzua, Thiago N.; Wojtas, Lukasz; Cui, Xin

    2014-01-01

    The Co(II) complex of the D2h-symmetric amidoporphyrin 3,5-DitBu-IbuPhyrin, [Co(P1)], has proven to be an effective metalloradical catalyst for intermolecular amination of C(sp2)–H bonds of aldehydes with fluoroaryl azides. The [Co(P1)]-catalyzed process can employ aldehydes as the limiting reagents and operate under neutral and non-oxidative conditions, generating nitrogen gas as the only byproduct. The metalloradical aldehydic C–H amination is suitable for different combinations of aldehydes and fluoroaryl azides, producing the corresponding N-fluoroaryl amides in good to excellent yields. A series of mechanistic studies support a stepwise radical mechanism for the Co(II)-catalyzed intermolecular C–H amination. PMID:25071929

  16. Molecular, biochemical, and functional characterization of a Nudix hydrolase protein that stimulates the activity of a nicotinoprotein alcohol dehydrogenase.

    PubMed

    Kloosterman, Harm; Vrijbloed, Jan W; Dijkhuizen, Lubbert

    2002-09-20

    The cytoplasmic coenzyme NAD(+)-dependent alcohol (methanol) dehydrogenase (MDH) employed by Bacillus methanolicus during growth on C(1)-C(4) primary alcohols is a decameric protein with 1 Zn(2+)-ion and 1-2 Mg(2+)-ions plus a tightly bound NAD(H) cofactor per subunit (a nicotinoprotein). Mg(2+)-ions are essential for binding of NAD(H) cofactor in MDH protein expressed in Escherichia coli. The low coenzyme NAD(+)-dependent activity of MDH with C(1)-C(4) primary alcohols is strongly stimulated by a second B. methanolicus protein (ACT), provided that MDH contains NAD(H) cofactor and Mg(2+)-ions are present in the assay mixture. Characterization of the act gene revealed the presence of the highly conserved amino acid sequence motif typical of Nudix hydrolase proteins in the deduced ACT amino acid sequence. The act gene was successfully expressed in E. coli allowing purification and characterization of active ACT protein. MDH activation by ACT involved hydrolytic removal of the nicotinamide mononucleotide NMN(H) moiety of the NAD(H) cofactor of MDH, changing its Ping-Pong type of reaction mechanism into a ternary complex reaction mechanism. Increased cellular NADH/NAD(+) ratios may reduce the ACT-mediated activation of MDH, thus preventing accumulation of toxic aldehydes. This represents a novel mechanism for alcohol dehydrogenase activity regulation.

  17. Me3SiI-promoted reaction of salicylic aldehydes with ketones: a facile way to construct benzopyranic [2,3-b]ketals and spiroketals.

    PubMed

    Wang, Feijun; Qu, Mingliang; Lu, Xi; Chen, Feng; Chen, Feng; Shi, Min

    2012-06-25

    Me(3)SiI-promoted reaction of salicylic aldehydes with ketones via arylmethylation at the α-site of the carbonyl group and cyclodehydration of keto-diol provided a facile way to construct heteroannular ketals, furnishing benzopyranic [2,3-b]ketals and spiroketals in moderate to good yields.

  18. Allyl transfer to aldehydes and ketones by Brønsted acid activation of allyl and crotyl 1,3,2-dioxazaborolidines.

    PubMed

    Reilly, Maureen K; Rychnovsky, Scott D

    2010-11-05

    Alkyl dioxazaborolidines are air-stable and often crystalline organoboranes. A variety of Brønsted acids activate allyl dioxazaborolidines to generate reactive allyl-transfer reagents in situ. These reagents add to aldehydes and ketones to generate the corresponding alcohols in good yields under mild conditions. The E- and Z-crotyl reagents react diastereoselectively with aldehydes and ketones to produce anti and syn adducts, respectively, a result consistent with a cyclic transition state (type I mechanism).

  19. Mitochondria-targeted ubiquinone (MitoQ) enhances acetaldehyde clearance by reversing alcohol-induced posttranslational modification of aldehyde dehydrogenase 2: A molecular mechanism of protection against alcoholic liver disease.

    PubMed

    Hao, Liuyi; Sun, Qian; Zhong, Wei; Zhang, Wenliang; Sun, Xinguo; Zhou, Zhanxiang

    2018-04-01

    Alcohol metabolism in the liver generates highly toxic acetaldehyde. Breakdown of acetaldehyde by aldehyde dehydrogenase 2 (ALDH2) in the mitochondria consumes NAD + and generates reactive oxygen/nitrogen species, which represents a fundamental mechanism in the pathogenesis of alcoholic liver disease (ALD). A mitochondria-targeted lipophilic ubiquinone (MitoQ) has been shown to confer greater protection against oxidative damage in the mitochondria compared to untargeted antioxidants. The present study aimed to investigate if MitoQ could preserve mitochondrial ALDH2 activity and speed up acetaldehyde clearance, thereby protects against ALD. Male C57BL/6J mice were exposed to alcohol for 8 weeks with MitoQ supplementation (5mg/kg/d) for the last 4 weeks. MitoQ ameliorated alcohol-induced oxidative/nitrosative stress and glutathione deficiency. It also reversed alcohol-reduced hepatic ALDH activity and accelerated acetaldehyde clearance through modulating ALDH2 cysteine S-nitrosylation, tyrosine nitration and 4-hydroxynonenol adducts formation. MitoQ ameliorated nitric oxide (NO) donor-mediated ADLH2 S-nitrosylation and nitration in Hepa-1c1c7 cells under glutathion depletion condition. In addition, alcohol-increased circulating acetaldehyde levels were accompanied by reduced intestinal ALDH activity and impaired intestinal barrier. In accordance, MitoQ reversed alcohol-increased plasma endotoxin levels and hepatic toll-like receptor 4 (TLR4)-NF-κB signaling along with subsequent inhibition of inflammatory cell infiltration. MitoQ also reversed alcohol-induced hepatic lipid accumulation through enhancing fatty acid β-oxidation. Alcohol-induced ER stress and apoptotic cell death signaling were reversed by MitoQ. This study demonstrated that speeding up acetaldehyde clearance by preserving ALDH2 activity critically mediates the beneficial effect of MitoQ on alcohol-induced pathogenesis at the gut-liver axis. Copyright © 2017 The Authors. Published by Elsevier B

  20. Reactive aldehyde metabolites from the anti-HIV drug abacavir: amino acid adducts as possible factors in abacavir toxicity.

    PubMed

    Charneira, Catarina; Godinho, Ana L A; Oliveira, M Conceição; Pereira, Sofia A; Monteiro, Emília C; Marques, M Matilde; Antunes, Alexandra M M

    2011-12-19

    Abacavir is a nucleoside reverse transcriptase inhibitor marketed since 1999 for the treatment of infection with the human immunodeficiency virus type 1 (HIV). Despite its clinical efficacy, abacavir administration has been associated with serious and sometimes fatal toxic events. Abacavir has been reported to undergo bioactivation in vitro, yielding reactive species that bind covalently to human serum albumin, but the haptenation mechanism and its significance to the toxic events induced by this anti-HIV drug have yet to be elucidated. Abacavir is extensively metabolized in the liver, resulting in inactive glucuronide and carboxylate metabolites. The metabolism of abacavir to the carboxylate involves a two-step oxidation via an unconjugated aldehyde, which under dehydrogenase activity isomerizes to a conjugated aldehyde. Concurrently with metabolic oxidation, the two putative aldehyde metabolites may be trapped by nucleophilic side groups in proteins yielding covalent adducts, which can be at the onset of the toxic events associated with abacavir. To gain insight into the role of aldehyde metabolites in abacavir-induced toxicity and with the ultimate goal of preparing reliable and fully characterized prospective biomarkers of exposure to the drug, we synthesized the two putative abacavir aldehyde metabolites and investigated their reaction with the α-amino group of valine. The resulting adducts were subsequently stabilized by reduction with sodium cyanoborohydride and derivatized with phenyl isothiocyanate, leading in both instances to the formation of the same phenylthiohydantoin, which was fully characterized by NMR and MS. These results suggest that the unconjugated aldehyde, initially formed in vivo, rapidly isomerizes to the thermodynamically more stable conjugated aldehyde, which is the electrophilic intermediate mainly involved in reaction with bionucleophiles. Moreover, we demonstrated that the reaction of the conjugated aldehyde with nitrogen

  1. Kinetic alteration of a human dihydrodiol/3alpha-hydroxysteroid dehydrogenase isoenzyme, AKR1C4, by replacement of histidine-216 with tyrosine or phenylalanine.

    PubMed Central

    Ohta, T; Ishikura, S; Shintani, S; Usami, N; Hara, A

    2000-01-01

    Human dihydrodiol dehydrogenase with 3alpha-hydroxysteroid dehydrogenase activity exists in four forms (AKR1C1-1C4) that belong to the aldo-keto reductase (AKR) family. Recent crystallographic studies on the other proteins in this family have indicated a role for a tyrosine residue (corresponding to position 216 in these isoenzymes) in stacking the nicotinamide ring of the coenzyme. This tyrosine residue is conserved in most AKR family members including AKR1C1-1C3, but is replaced with histidine in AKR1C4 and phenylalanine in some AKR members. In the present study we prepared mutant enzymes of AKR1C4 in which His-216 was replaced with tyrosine or phenylalanine. The two mutations decreased 3-fold the K(m) for NADP(+) and differently influenced the K(m) and k(cat) for substrates depending on their structures. The kinetic constants for bile acids with a 12alpha-hydroxy group were decreased 1.5-7-fold and those for the other substrates were increased 1.3-9-fold. The mutation also yielded different changes in sensitivity to competitive inhibitors such as hexoestrol analogues, 17beta-oestradiol, phenolphthalein and flufenamic acid and 3,5,3', 5'-tetraiodothyropropionic acid analogues. Furthermore, the mutation decreased the stimulatory effects of the enzyme activity by sulphobromophthalein, clofibric acid and thyroxine, which increased the K(m) for the coenzyme and substrate of the mutant enzymes more highly than those of the wild-type enzyme. These results indicate the importance of this histidine residue in creating the cavity of the substrate-binding site of AKR1C4 through the orientation of the nicotinamide ring of the coenzyme, as well as its involvement in the conformational change by binding non-essential activators. PMID:11104674

  2. UVB induces epidermal 11β-hydroxysteroid dehydrogenase type 1 activity in vivo.

    PubMed

    Tiganescu, Ana; Hupe, Melanie; Jiang, Yan J; Celli, Anna; Uchida, Yoshikazu; Mauro, Theodora M; Bikle, Daniel D; Elias, Peter M; Holleran, Walter M

    2015-05-01

    Detrimental consequences of ultraviolet radiation (UVR) in skin include photoageing, immunosuppression and photocarcinogenesis, processes also significantly regulated by local glucocorticoid (GC) availability. In man, the enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) generates the active GC cortisol from cortisone (or corticosterone from 11-dehydrocorticosterone in rodents). 11β-HSD1 oxo-reductase activity requires the cofactor NADPH, generated by hexose-6-phosphate dehydrogenase. We previously demonstrated increased 11β-HSD1 levels in skin obtained from photoexposed versus photoprotected anatomical regions. However, the direct effect of UVR on 11β-HSD1 expression remains to be elucidated. To investigate the cutaneous regulation of 11β-HSD1 following UVR in vivo, the dorsal skin of female SKH1 mice was irradiated with 50, 100, 200 and 400 mJ/cm(2) UVB. Measurement of transepidermal water loss, 11β-HSD1 activity, mRNA/protein expression and histological studies was taken at 1, 3 and 7 days postexposure. 11β-HSD1 and hexose-6-phosphate dehydrogenase mRNA expression peaked 1 day postexposure to 400 mJ/cm(2) UVB before subsequently declining (days 3 and 7). Corresponding increases in 11β-HSD1 protein and enzyme activity were observed 3 days postexposure coinciding with reduced GC receptor mRNA expression. Immunofluorescence studies revealed 11β-HSD1 localization to hyperproliferative epidermal keratinocytes in UVB-exposed skin. 11β-HSD1 expression and activity were also induced by 200 and 100 (but not 50) mJ/cm(2) UVB and correlated with increased transepidermal water loss (indicative of barrier disruption). UVB-induced 11β-HSD1 activation represents a novel mechanism that may contribute to the regulation of cutaneous responses to UVR exposure. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Expressional studies of the aldehyde oxidase (AOX1) gene during myogenic differentiation in C2C12 cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kamli, Majid Rasool; Kim, Jihoe; Pokharel, Smritee

    2014-08-08

    Highlights: • AOX1 contributes to the formation of myotube. • Silencing of AOX1 reduces myotube formation. • AOX1 regulates MyoG gene expression. • AOX1 contributes to myogenesis via H{sub 2}O{sub 2}. - Abstract: Aldehyde oxidases (AOXs), which catalyze the hydroxylation of heterocycles and oxidation of a wide variety of aldehydic compounds, have been present throughout evolution from bacteria to humans. While humans have only a single functional aldehyde oxidase (AOX1) gene, rodents are endowed with four AOXs; AOX1 and three aldehyde oxidase homologs (AOH1, AOH2 and AOH3). In continuation of our previous study conducted to identify genes differentially expressed duringmore » myogenesis using a microarray approach, we investigated AOX1 with respect to its role in myogenesis to conceptualize how it is regulated in C2C12 cells. The results obtained were validated by silencing of the AOX1 gene. Analysis of their fusion index revealed that formation of myotubes showed a marked reduction of up to 40% in AOX1{sub kd} cells. Expression of myogenin (MYOG), one of the marker genes used to study myogenesis, was also found to be reduced in AOX1{sub kd} cells. AOX1 is an enzyme of pharmacological and toxicological importance that metabolizes numerous xenobiotics to their respective carboxylic acids. Hydrogen peroxide (H{sub 2}O{sub 2}) produced as a by-product in this reaction is considered to be involved as a part of the signaling mechanism during differentiation. An observed reduction in the level of H{sub 2}O{sub 2} among AOX1{sub kd} cells confirmed production of H{sub 2}O{sub 2} in the reaction catalyzed by AOX1. Taken together, these findings suggest that AOX1 acts as a contributor to the process of myogenesis by influencing the level of H{sub 2}O{sub 2}.« less

  4. MICROBIAL GROWTH ON C-1 COMPOUNDS. 6. OXIDATION OF METHANOL, FORMALDEHYDE AND FORMATE BY METHANOL-GROWN PSEUDOMONAS AM 1,

    DTIC Science & Technology

    oxidizing methanol that could be demonstrated was a dehydrogenase that can be linked to phenazine methosulphate and required the presence of NH4(+) ions...An aldehyde dehydrogenase that reduced 2,6-dichlorophenol-indophenol or phenazine methosulphate in the presence of formaldehyde was found in cell

  5. Allyl Transfer to Aldehydes and Ketones by Brønsted Acid Activation of Allyl and Crotyl 1,3,2-Dioxazaborolidines

    PubMed Central

    Reilly, Maureen K.; Rychnovsky, Scott D.

    2010-01-01

    Alkyl dioxazaborolidines are air-stable and often crystalline organoboranes. A variety of Brønsted acids activate allyl dioxazaborolidines to generate reactive allyl-transfer reagents in situ. These reagents add to aldehydes and ketones to generate the corresponding alcohols in good yields under mild conditions. The E- and Z-crotyl reagents react diastereoselectively with aldehydes and ketones to produce anti and syn adducts, respectively, a result consistent with a cyclic transition state (Type I mechanism). PMID:20942379

  6. Cu(I)-catalyzed transannulation of N-heteroaryl aldehydes or ketones with alkylamines via C(sp3)-H amination.

    PubMed

    Li, Mingyang; Xie, Ying; Ye, Yong; Zou, Yong; Jiang, Huanfeng; Zeng, Wei

    2014-12-05

    A copper(I)-catalyzed direct transannulation of N-heteroaryl aldehydes or ketones with alkylamines via Csp(3)-H amination has been achieved using molecular oxygen as a sole oxidant. N-Heteroarenes are employed as the amine source. This transformation provides a rapid and concise access to multifunctional imidazo[1,5-a]pyridines.

  7. A Novel 3-Hydroxysteroid Dehydrogenase That Regulates Reproductive Development and Longevity

    PubMed Central

    Wollam, Joshua; Magner, Daniel B.; Magomedova, Lilia; Rass, Elisabeth; Shen, Yidong; Rottiers, Veerle; Habermann, Bianca; Cummins, Carolyn L.; Antebi, Adam

    2012-01-01

    Endogenous small molecule metabolites that regulate animal longevity are emerging as a novel means to influence health and life span. In C. elegans, bile acid-like steroids called the dafachronic acids (DAs) regulate developmental timing and longevity through the conserved nuclear hormone receptor DAF-12, a homolog of mammalian sterol-regulated receptors LXR and FXR. Using metabolic genetics, mass spectrometry, and biochemical approaches, we identify new activities in DA biosynthesis and characterize an evolutionarily conserved short chain dehydrogenase, DHS-16, as a novel 3-hydroxysteroid dehydrogenase. Through regulation of DA production, DHS-16 controls DAF-12 activity governing longevity in response to signals from the gonad. Our elucidation of C. elegans bile acid biosynthetic pathways reveals the possibility of novel ligands as well as striking biochemical conservation to other animals, which could illuminate new targets for manipulating longevity in metazoans. PMID:22505847

  8. Sequence of the cDNA of a human dihydrodiol dehydrogenase isoform (AKR1C2) and tissue distribution of its mRNA.

    PubMed Central

    Shiraishi, H; Ishikura, S; Matsuura, K; Deyashiki, Y; Ninomiya, M; Sakai, S; Hara, A

    1998-01-01

    Human liver contains three isoforms (DD1, DD2 and DD4) of dihydrodiol dehydrogenase with 20alpha- or 3alpha-hydroxysteroid dehydrogenase activity; the dehydrogenases belong to the aldo-oxo reductase (AKR) superfamily. cDNA species encoding DD1 and DD4 have been identified. However, four cDNA species with more than 99% sequence identity have been cloned and are compatible with a partial amino acid sequence of DD2. In this study we have isolated a cDNA clone encoding DD2, which was confirmed by comparison of the properties of the recombinant and hepatic enzymes. This cDNA showed differences of one, two, four and five nucleotides from the previously reported four cDNA species for a dehydrogenase of human colon carcinoma HT29 cells, human prostatic 3alpha-hydroxysteroid dehydrogenase, a human liver 3alpha-hydroxysteroid dehydrogenase-like protein and chlordecone reductase-like protein respectively. Expression of mRNA species for the five similar cDNA species in 20 liver samples and 10 other different tissue samples was examined by reverse transcriptase-mediated PCR with specific primers followed by diagnostic restriction with endonucleases. All the tissues expressed only one mRNA species corresponding to the newly identified cDNA for DD2: mRNA transcripts corresponding to the other cDNA species were not detected. We suggest that the new cDNA is derived from the principal gene for DD2, which has been named AKR1C2 by a new nomenclature for the AKR superfamily. It is possible that some of the other cDNA species previously reported are rare allelic variants of this gene. PMID:9716498

  9. The First Mammalian Aldehyde Oxidase Crystal Structure

    PubMed Central

    Coelho, Catarina; Mahro, Martin; Trincão, José; Carvalho, Alexandra T. P.; Ramos, Maria João; Terao, Mineko; Garattini, Enrico; Leimkühler, Silke; Romão, Maria João

    2012-01-01

    Aldehyde oxidases (AOXs) are homodimeric proteins belonging to the xanthine oxidase family of molybdenum-containing enzymes. Each 150-kDa monomer contains a FAD redox cofactor, two spectroscopically distinct [2Fe-2S] clusters, and a molybdenum cofactor located within the protein active site. AOXs are characterized by broad range substrate specificity, oxidizing different aldehydes and aromatic N-heterocycles. Despite increasing recognition of its role in the metabolism of drugs and xenobiotics, the physiological function of the protein is still largely unknown. We have crystallized and solved the crystal structure of mouse liver aldehyde oxidase 3 to 2.9 Å. This is the first mammalian AOX whose structure has been solved. The structure provides important insights into the protein active center and further evidence on the catalytic differences characterizing AOX and xanthine oxidoreductase. The mouse liver aldehyde oxidase 3 three-dimensional structure combined with kinetic, mutagenesis data, molecular docking, and molecular dynamics studies make a decisive contribution to understand the molecular basis of its rather broad substrate specificity. PMID:23019336

  10. Influences of cinnamic aldehydes on H⁺ extrusion activity and ultrastructure of Candida.

    PubMed

    Shreaz, Sheikh; Bhatia, Rimple; Khan, Neelofar; Muralidhar, Sumathi; Manzoor, Nikhat; Khan, Luqman Ahmad

    2013-02-01

    The antifungal effects of cinnamaldehyde, 4-hydroxy-3-methoxycinnamaldehyde (coniferyl aldehyde) and 3,5-dimethoxy-4-hydroxycinnamaldehyde (sinapaldehyde) were investigated against 65 strains of Candida (six standard, 39 fluconazole-sensitive and 20 fluconazole-resistant). MICs of cinnamaldehyde, coniferyl aldehyde and sinapaldehyde ranged from 100 to 500 µg ml(-1), 100 to 300 µg ml(-1) and 100 to 200 µg ml(-1), respectively. All tested isolates showed a marked sensitivity towards these aldehydes in spot and time-kill assays. Sinapaldehyde was found to be the most effective, followed by coniferyl aldehyde and cinnamaldehyde. At their respective MIC(90) values, the three compounds caused mean inhibition levels of glucose-stimulated H(+)-efflux of 36, 34 and 41 % (cinnamaldehyde), 41, 42 and 47 % (coniferyl aldehyde) and 43, 45 and 51 % (sinapaldehyde) for standard-sensitive, clinical-sensitive and clinical-resistant isolates, respectively. Inhibition levels of H(+)-efflux caused by plasma membrane ATPase inhibitors N,N'-dicyclohexylcarbodiimide (100 µM) and diethylstilbestrol (10 µM) were 34, 45 and 44 %, and 57, 39 and 35 %, for standard-sensitive, clinical-sensitive and clinical-resistant isolates, respectively. Intracellular pH (pHi) was found to decrease by 0.34, 0.42 and 0.50 units following incubation with three tested aldehydes from the control pHi of 6.70. Scanning electron microscopy and transmission electron microscopy analysis was performed on a representative strain, C. albicans 10261, showing alterations in morphology, cell wall, plasma membrane damage and lysis. Haemolytic activity of the three compounds varied from 10 to 15 % at their highest MIC compared to an activity level of 20 % shown by fluconazole at 30 µg ml(-1). In conclusion, this study shows significant activity of cinnamic aldehydes against Candida, including azole-resistant strains, suggesting that these molecules can be developed as antifungals.

  11. Plasmodium glyceraldehyde-3-phosphate dehydrogenase: A potential malaria diagnostic target.

    PubMed

    Krause, Robert G E; Hurdayal, Ramona; Choveaux, David; Przyborski, Jude M; Coetzer, Theresa H T; Goldring, J P Dean

    2017-08-01

    Malaria rapid diagnostic tests (RDTs) are immunochromatographic tests detecting Plasmodial histidine-rich protein 2 (HRP2), lactate dehydrogenase (LDH) and aldolase. HRP2 is only expressed by Plasmodium falciparum parasites and the protein is not expressed in several geographic isolates. LDH-based tests lack sensitivity compared to HRP2 tests. This study explored the potential of the Plasmodial glycolytic enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), as a new malaria diagnostic biomarker. The P. falciparum and P. yoelii proteins were recombinantly expressed in BL21(DE3) Escherischia coli host cells and affinity purified. Two epitopes (CADGFLLIGEKKVSVFA and CAEKDPSQIPWGKCQV) specific to P. falciparum GAPDH and one common to all mammalian malaria species (CKDDTPIYVMGINH) were identified. Antibodies were raised in chickens against the two recombinant proteins and the three epitopes and affinity purified. The antibodies detected the native protein in parasite lysates as a 38 kDa protein and immunofluorescence verified a parasite cytosolic localization for the native protein. The antibodies suggested a 4-6 fold higher concentration of native PfGAPDH compared to PfLDH in immunoprecipitation and ELISA formats, consistent with published proteomic data. PfGAPDH shows interesting potential as a malaria diagnostic biomarker. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Thermostable Alcohol Dehydrogenase from Thermococcus kodakarensis KOD1 for Enantioselective Bioconversion of Aromatic Secondary Alcohols

    PubMed Central

    Wu, Xi; Zhang, Chong; Orita, Izumi; Imanaka, Tadayuki

    2013-01-01

    A novel thermostable alcohol dehydrogenase (ADH) showing activity toward aromatic secondary alcohols was identified from the hyperthermophilic archaeon Thermococcus kodakarensis KOD1 (TkADH). The gene, tk0845, which encodes an aldo-keto reductase, was heterologously expressed in Escherichia coli. The enzyme was found to be a monomer with a molecular mass of 31 kDa. It was highly thermostable with an optimal temperature of 90°C and a half-life of 4.5 h at 95°C. The apparent Km values for the cofactors NAD(P)+ and NADPH were similar within a range of 66 to 127 μM. TkADH preferred secondary alcohols and accepted various ketones and aldehydes as substrates. Interestingly, the enzyme could oxidize 1-phenylethanol and its derivatives having substituents at the meta and para positions with high enantioselectivity, yielding the corresponding (R)-alcohols with optical purities of greater than 99.8% enantiomeric excess (ee). TkADH could also reduce 2,2,2-trifluoroacetophenone to (R)-2,2,2-trifluoro-1-phenylethanol with high enantioselectivity (>99.6% ee). Furthermore, the enzyme showed high resistance to organic solvents and was particularly highly active in the presence of H2O–20% 2-propanol and H2O–50% n-hexane or n-octane. This ADH is expected to be a useful tool for the production of aromatic chiral alcohols. PMID:23354700

  13. A reactive and sensitive diffusion sampler for the determination of aldehydes and ketones in ambient air

    NASA Astrophysics Data System (ADS)

    Uchiyama, Shigehisa; Hasegawa, Shuji

    We developed a diffusive sampling device (DSD-carbonyl) for organic carbonyl compounds (aldehydes and ketones) which is suitable for collection and analysis of low concentration levels. This sampling device is composed of three parts, an exposure part made of a porous polytetrafluoroethylene (PPTFE) tube, an analysis part made of polypropylene (PP) tubing and an absorbent part made of 2,4-dinitrophenylhydrazine (DNPH) coated silica gel (DNPH-silica). Aldehydes and ketones diffuse to the DSD-carbonyl through PPTFE-tube by the mechanism of molecular diffusion and react specifically with DNPH to form a stable DNPH-derivatives. Collection is controlled by moving the absorbent from the exposure part to the analysis part by changing the posture of the DSD-carbonyl. DNPH-derivatives were eluted from an analysis part of DSD-carbonyl with acetonitrile directly and analyzed by high performance liquid chromatography (HPLC). The advantages of the DSD-carbonyl are the following: (1) The DSD-carbonyl can be used in a wide range of concentration of aldehydes and ketones in atmosphere, as the DSD-carbonyl exposure part has a variable diffusion area, (2) DNPH-derivatives are eluted from DNPH-silica without contamination of air. (3) The sampler can be applied to active sampling by connecting it with a pump. The limit of detection (LOD) for concentrations of major aldehydes and ketones ranged from 0.072 to 0.13 ppb, and the limit of quantitation (LOQ) ranged from 0.24 to 0.42 ppb. The coefficient variation (CV) for concentrations of major aldehydes and ketones ranged from 2.5 to 3.0% in laboratory air. The DSD-carbonyl method and active sampling method (US EPA method IP-6A) showed a good correlation (formaldehyde, r2=0.995). The uptake rates for formaldehyde, acetaldehyde, and acetone were estimated as 0.078, 0.062 and 0.079 nmol ppb -1 h -1, respectively. It is possible to estimate atmospheric aldehydes and ketones at parts per billion (ppb), with high sensitivity and precision, by

  14. Synthesis of β-C-Glycopyranosyl Aldehydes and 2,6-Anhydro-heptitols.

    PubMed

    Khatri, Vinod; Kumar, Amit; Singh, Balram; Malhotra, Shashwat; Prasad, Ashok K

    2015-11-06

    A convenient route has been developed for the diastereoselective synthesis of β-C-glycopyranosyl aldehydes from D-glucose, D-mannose, and D-galactose. The key step in the synthesis of C-glycosyl aldehydes is the aryl driven reductive dehydration on 1-phenyl-2-(2',3',4',6'-tetra-O-acetyl-β-D-glycopyranosyl)ethanone to afford alkenes, which on oxidation afford the desired compounds in good yield. β-C-Glycopyranosyl aldehydes have been converted to 2,6-anhydro-heptitols in quantitative yields. The 2,6-anhydro-heptitols derived from D-mannose and D-galactose are enantiomeric and are useful linkers for the synthesis of macrocycles/amphiphiles of complementary chirality.

  15. Crystallization and preliminary X-ray diffraction analysis of mouse 3(17)α-hydroxysteroid dehydrogenase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    El-Kabbani, Ossama, E-mail: ossama.el-kabbani@vcp.monash.edu.au; Ishikura, Syuhei; Wagner, Armin

    2005-07-01

    Orthorhombic crystals of mouse 3(17)α-hydroxysteroid dehydrogenase were obtained from buffered polyethylene glycol solutions. The crystals diffracted to a resolution of 1.8 Å at the Swiss Light Source beamline X06SA. The 3(17)α-hydroxysteroid dehydrogenase from mouse is involved in the metabolism of oestrogens, androgens, neurosteroids and xenobiotic compounds. The enzyme was crystallized by the hanging-drop vapour-diffusion method in space group P222{sub 1}, with unit-cell parameters a = 84.91, b = 84.90, c = 95.83 Å. The Matthews coefficient (V{sub M}) and the solvent content were 2.21 Å{sup 3} Da{sup −1} and 44.6%, respectively, assuming the presence of two molecules in the asymmetricmore » unit. Diffraction data were collected to a resolution of 1.8 Å at the Swiss Light Source beamline X06SA using a MAR CCD area detector and gave a data set with an overall R{sub merge} of 6.8% and a completeness of 91.1%.« less

  16. Nickel-catalyzed cycloadditions of unsaturated hydrocarbons, aldehydes, and ketones.

    PubMed

    Tekavec, Thomas N; Louie, Janis

    2008-04-04

    The nickel-catalyzed cycloaddition of unsaturated hydrocarbons and carbonyls is reported. Diynes and enynes were used as coupling partners. Carbonyl substrates include both aldehdyes and ketones. Reactions of diynes and aldehydes afforded the [3,3] electrocyclic ring-opened tautomers, rather than pyrans, in high yields. The cycloaddition reaction of enynes and aldehydes afforded two distinct products. A new carbon-carbon bond is formed, prior to a competitive beta-hydrogen elimination of a nickel alkoxide, between the carbonyl carbon and either one of the carbons of the olefin or the alkyne. The steric hindrance of the enyne greatly affected the chemoselectivity of the cycloaddition of enynes and aldehydes. In some cases, dihydropyran was also formed. The scope of the cycloaddition reaction was expanded to include the coupling of enynes and ketones. No beta-hydrogen elimination was observed in cycloaddition reaction of enynes and ketones. Instead, C-O bond-forming reductive elimination occurred exclusively to afford dihydropyrans in excellent yields. In all cases, complete chemoselectivity was observed; only dihydropyrans where the carbonyl carbon forms a carbon-carbon bond with a carbon of the olefin, rather than of the alkyne, were observed. All cycloaddition reactions occur at room temperature and employ nickel catalysts bearing the hindered 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) or its saturated analogue, 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazolin-2-ylidene (SIPr).

  17. Nickel-Catalyzed Cycloadditions of Unsaturated Hydrocarbons, Aldehydes, and Ketones

    PubMed Central

    Tekavec, Thomas N.

    2014-01-01

    The nickel-catalyzed cycloaddition of unsaturated hydrocarbons and carbonyls is reported. Diynes and enynes were used as coupling partners. Carbonyl substrates include both aldehdyes and ketones. Reactions of diynes and aldehydes afforded the [3, 3] electrocyclic ring-opened tautomers, rather than pyrans, in high yields. The cycloaddition reaction of enynes and aldehydes afforded two distinct products. A new carbon–carbon bond is formed, prior to a competitive β-hydrogen elimination of a nickel alkoxide, between the carbonyl carbon and either one of the carbons of the olefin or the alkyne. The steric hindrance of the enyne greatly affected the chemoselectivity of the cycloaddition of enynes and aldehydes. In some cases, dihydropyran was also formed. The scope of the cycloaddition reaction was expanded to include the coupling of enynes and ketones. No β-hydrogen elimination was observed in cycloaddition reaction of enynes and ketones. Instead, C–O bond-forming reductive elimination occurred exclusively to afford dihydropyrans in excellent yields. In all cases, complete chemoselectivity was observed; only dihydropyrans where the carbonyl carbon forms a carbon–carbon bond with a carbon of the olefin, rather than of the alkyne, were observed. All cycloaddition reactions occur at room temperature and employ nickel catalysts bearing the hindered 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) or its saturated analogue, 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazolin-2-ylidene (SIPr). PMID:18318544

  18. Topically applied metal chelator reduces thermal injury progression in a rat model of brass comb burn.

    PubMed

    Wang, Cheng Z; Ayadi, Amina El; Goswamy, Juhi; Finnerty, Celeste C; Mifflin, Randy; Sousse, Linda; Enkhbaatar, Perenlei; Papaconstantinou, John; Herndon, David N; Ansari, Naseem H

    2015-12-01

    Oxidative stress may be involved in the cellular damage and tissue destruction as burn wounds continues to progress after abatement of the initial insult. Since iron and calcium ions play key roles in oxidative stress, this study tested whether topical application of Livionex formulation (LF) lotion, that contains disodium EDTA as a metal chelator and methyl sulfonyl methane (MSM) as a permeability enhancer, would prevent or reduce burns. We used an established brass comb burn model with some modifications. Topical application of LF lotion was started 5 min post-burn, and repeated every 8 h for 3 consecutive days. Rats were euthanized and skin harvested for histochemistry and immunohistochemistry. Formation of protein adducts of 4-hydroxynonenal (HNE), malonadialdehyde (MDA) and acrolein (ACR) and expression of aldehyde dehydrogenase (ALDH) isozymes, ALDH1 and ALDH2 were assessed. LF lotion-treated burn sites and interspaces showed mild morphological improvement compared to untreated burn sites. Furthermore, the lotion significantly decreased the immunostaining of lipid aldehyde-protein adducts including protein -HNE, -MDA and -ACR adducts, and restored the expression of aldehyde dehydrogenase isozymes in the unburned interspaces. This data, for the first time, demonstrates that a topically applied EDTA-containing lotion protects burns progression with a concomitant decrease in the accumulation of reactive lipid aldehydes and protection of aldehyde dehydrogenase isozymes. Present studies are suggestive of therapeutic intervention of burns by this novel lotion. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  19. Topically Applied Metal Chelator Reduces Thermal Injury Progression in a Rat Model of Brass Comb Burn

    PubMed Central

    Wang, Cheng Z.; El Ayadi, Amina; Goswamy, Juhi; Finnerty, Celeste C.; Mifflin, Randy; Sousse, Linda; Enkhbaatar, Perenlei; Papaconstantinou, John; Herndon, David N.; Ansari, Naseem H.

    2016-01-01

    Oxidative stress may be involved in the cellular damage and tissue destruction as burn wounds continues to progress after abatement of the initial insult. Since iron and calcium ions play key roles in oxidative stress, this study tested whether topical application of Livionex formulation (LF) lotion, that contains disodium EDTA as a metal chelator and methyl sulfonyl methane (MSM) as a permeability enhancer, would prevent or reduce burn injury. Methods We used an established brass comb burn model with some modifications. Topical application of LF lotion was started 5 minutes post-burn, and repeated every 8 hours for 3 consecutive days. Rats were euthanized and skin harvested for histochemistry and immunohistochemistry. Formation of protein adducts of 4-hydroxynonenal (HNE), malonadialdehyde (MDA) and acrolein (ACR) and expression of aldehyde dehydrogenase (ALDH) isozymes, ALDH1 and ALDH2 were assessed. Results LF lotion-treated burn sites and interspaces showed mild morphological improvement compared to untreated burn sites. Furthermore, the lotion significantly decreased the immunostaining of lipid aldehyde-protein adducts including protein -HNE, -MDA and -ACR adducts, and restored the expression of aldehyde dehydrogenase isozymes in the unburned interspaces. Conclusion This data, for the first time, demonstrates that a topically applied EDTA-containing lotion protects burn injury progression with a concomitant decrease in the accumulation of reactive lipid aldehydes and protection of aldehyde dehydrogenase isozymes. Present studies are suggestive of therapeutic intervention of burn injury by this novel lotion. PMID:26392023

  20. In-Silico molecular docking and simulation studies on novel chalcone and flavone hybrid derivatives with 1, 2, 3-triazole linkage as vital inhibitors of Plasmodium falciparum dihydroorotate dehydrogenase.

    PubMed

    Thillainayagam, Mahalakshmi; Malathi, Kullappan; Ramaiah, Sudha

    2017-11-27

    The structural motifs of chalcones, flavones, and triazoles with varied substitutions have been studied for the antimalarial activity. In this study, 25 novel derivatives of chalcone and flavone hybrid derivatives with 1, 2, 3-triazole linkage are docked with Plasmodium falciparum dihydroorotate dehydrogenase to establish their inhibitory activity against Plasmodium falciparum. The best binding conformation of the ligands at the catalytic site of dihydroorotate dehydrogenase are selected to characterize the best bound ligand using the best consensus score and the number of hydrogen bond interactions. The ligand namely (2E)-3-(4-{[1-(3-chloro-4-fluorophenyl)-1H-1, 2, 3-triazol-4-yl]methoxy}-3-methoxyphenyl-1-(2-hydroxy-4,6-dimethoxyphenyl)prop-2-en-1-one, is one the among the five best docked ligands, which interacts with the protein through nine hydrogen bonds and with a consensus score of five. To refine and confirm the docking study results, the stability of complexes is verified using Molecular Dynamics Simulations, Molecular Mechanics /Poisson-Boltzmann Surface Area free binding energy analysis, and per residue contribution for the binding energy. The study implies that the best docked Plasmodium falciparum dihydroorotate dehydrogenase-ligand complex is having high negative binding energy, most stable, compact, and rigid with nine hydrogen bonds. The study provides insight for the optimization of chalcone and flavone hybrids with 1, 2, 3-triazole linkage as potent inhibitors.

  1. Structure-activity relationship study of peptidomimetic aldehydes as enterovirus 71 3C protease inhibitors.

    PubMed

    Zhai, Yangyang; Ma, Yuying; Ma, Fei; Nie, Quandeng; Ren, Xuejiao; Wang, Yaxin; Shang, Luqing; Yin, Zheng

    2016-11-29

    A series of peptidomimetic aldehydes were designed, synthesized, and evaluated for their biochemical activity against 3C protease (3C pro ) and anti-enterovirus 71 (EV71) activity in vitro. Molecular docking revealed that 5s (IC 50  = 0.22 ± 0.07 μM, EC 50  = 0.18 ± 0.05 μM) could bind well to the active site of EV71 3C pro , which was consistent with the biological data compared to reference 5a (IC 50  = 0.54 ± 0.02 μM, EC 50  = 0.26 ± 0.07 μM). Structure and relationship study led to the discovery of aldehyde 5x (IC 50  = 0.10 ± 0.02 μM, EC 50  = 0.11 ± 0.07 μM), which exhibited the most potent 3C pro inhibitory and antiviral activity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  2. Glyceraldehyde 3-phosphate dehydrogenase negatively regulates human immunodeficiency virus type 1 infection

    PubMed Central

    2012-01-01

    Background Host proteins are incorporated inside human immunodeficiency virus type 1 (HIV-1) virions during assembly and can either positively or negatively regulate HIV-1 infection. Although the identification efficiency of host proteins is improved by mass spectrometry, how those host proteins affect HIV-1 replication has not yet been fully clarified. Results In this study, we show that virion-associated glyceraldehyde 3-phosphate dehydrogenase (GAPDH) does not allosterically inactivate HIV-1 reverse transcriptase (RT) but decreases the efficiency of reverse transcription reactions by decreasing the packaging efficiency of lysyl-tRNA synthetase (LysRS) and tRNALys3 into HIV-1 virions. Two-dimensional (2D) gel electrophoresis demonstrated that some isozymes of GAPDH with different isoelectric points were expressed in HIV-1-producing CEM/LAV-1 cells, and a proportion of GAPDH was selectively incorporated into the virions. Suppression of GAPDH expression by RNA interference in CEM/LAV-1 cells resulted in decreased GAPDH packaging inside the virions, and the GAPDH-packaging-defective virus maintained at least control levels of viral production but increased the infectivity. Quantitative analysis of reverse transcription products indicated that the levels of early cDNA products of the GAPDH-packaging-defective virus were higher than those of the control virus owing to the higher packaging efficiencies of LysRS and tRNALys3 into the virions rather than the GAPDH-dependent negative allosteric modulation for RT. Furthermore, immunoprecipitation assay using an anti-GAPDH antibody showed that GAPDH directly interacted with Pr55gag and p160gag-pol and the overexpression of LysRS in HIV-1-producing cells resulted in a decrease in the efficiency of GAPDH packaging in HIV particles. In contrast, the viruses produced from cells expressing a high level of GAPDH showed decreased infectivity in TZM-bl cells and reverse transcription efficiency in TZM-bl cells and peripheral blood

  3. Dehydrogenation of indanol by rabbit liver 3-hydroxyhexobarbital dehydrogenase.

    PubMed

    Takenoshita, R; Toki, S

    1977-06-01

    1. Among the several enzyme activities in rabbit liver cytosol able to dehydrogenate 1-indanol, only the main activity was not separable from 3-hydroxyhexobarbital dehydrogenase during purification including polyacrylamide gel disc electrophoresis. 2. Results of mixed substrate method indicated that the same enzyme catalyses the dehydrogenation of 1-indanol and 3-hydroxyhexobarbital. The ratio between the two dehydrogenation activities was almost constant as the enzyme underwent thermal inactivation. The Ki values of p-chloromercuribenzoate, the Km values for NAD+, and the Km values for NADP+ were very similar for the two dehydrogenations. These results lead to the conclusion that the same enzyme catalyses the dehydrogenation of 3-hydroxyhexobarbital and 1-indanol. 3. 1-Tetralol, 1-acenaphthenol, 9-fluorenol, thiochroman-4-ol and 4-chromanol also served as substrate of the enzyme, but 2-indanol, 2-tetralol, and trans- and cis-indan-1,2-diol were not oxidized. 4. Reversibility of the reaction was also confirmed using 1-indanone as substrate.

  4. MASS SPECTROMETRY OF FATTY ALDEHYDES

    PubMed Central

    Berdyshev, Evgeny V.

    2011-01-01

    Fatty aldehydes are important components of the cellular lipidome. Significant interest has been developed towards the analysis of the short chain α,β-unsaturated and hydroxylated aldehydes formed as a result of oxidation of polyunsaturated fatty acids. Multiple gas chromatography-mass spectrometry (GC/MS) and subsequently liquid chromatography-mass spectrometry (LC/MS) approaches have been developed to identify and quantify short-chain as well as long-chain fatty aldehydes. Due to the ability to non-enzymaticaly form Schiff bases with amino groups of proteins, lipids, and with DNA guanidine, free aldehydes are viewed as a marker or metric of fatty acid oxidation and not the part of intracellular signaling pathways which has significantly limited the overall attention this group of molecules have received. This review provides an overview of current GC/MS and LC/MS approaches of fatty aldehyde analysis as well as discusses technical challenges standing in the way of free fatty aldehyde quantitation. PMID:21930240

  5. Characterization of new recombinant 3-ketosteroid-Δ1-dehydrogenases for the biotransformation of steroids.

    PubMed

    Wang, Xiaojun; Feng, Jinhui; Zhang, Dalong; Wu, Qiaqing; Zhu, Dunming; Ma, Yanhe

    2017-08-01

    3-Ketosteroid-Δ 1 -dehydrogenases (KstDs [EC 1.3.99.4]) catalyze the Δ 1 -dehydrogenation of steroids and are a class of important enzymes for steroid biotransformations. In this study, we cloned 12 putative KstD-encoding (kstd) genes from both fungal and Gram-positive microorganisms and attempted to overproduce the recombinant proteins in E. coli BL21(DE3). Five successful recombinant enzymes catalyzed the Δ 1 -desaturation of a variety of steroidal compounds such as 4-androstene-3,17-dione (AD), 9α-hydroxy-4-androstene-3,17-dione (9-OH-AD), hydrocortisone, cortisone, and cortexolone. However, the substrate specificity and catalytic efficiency of the enzymes differ depending on their sources. The purified KstD from Mycobacterium smegmatis mc 2 155 (MsKstD1) displayed high catalytic efficiency toward hydrocortisone, progesterone, and 9-OH-AD, where it had the highest affinity (K m 36.9 ± 4.6 μM) toward 9-OH-AD. On the other hand, the KstD from Rhodococcus erythropolis WY 1406 (ReKstD) exhibited high catalytic efficiency toward androst-4,9(11)-diene-3,17-dione (Diene), 21-acetoxy-pregna-4,9(11),16-triene-3,20-dione (Triene), and cortexolone, where in all three cases the K m values (12.3 to 17.8 μM) were 2.5-4-fold lower than that toward hydrocortisone (46.3 μM). For both enzymes, AD was a good substrate although ReKstD had a 3-fold higher affinity than MsKstD1. Reaction conditions were optimized for the biotransformation of AD or hydrocortisone in terms of pH, temperature, and effects of hydrogen peroxide, solvent, and electron acceptor. For the biotransformation of hydrocortisone with 20 g/L wet resting E. coli cells harboring MsKstD1 enzyme, the yield of prednisolone was about 90% within 3 h at the substrate concentration of 6 g/L, demonstrating the application potential of the newly cloned KstDs.

  6. Enhanced expression of the Escherichia coli serA gene in a plasmid vector. Purification, crystallization, and preliminary X-ray data of D-3 phosphoglycerate dehydrogenase.

    PubMed

    Schuller, D J; Fetter, C H; Banaszak, L J; Grant, G A

    1989-02-15

    The serA gene of Escherichia coli strain K-12, which codes for the cooperative allosteric enzyme D-3-phosphoglycerate dehydrogenase, was inserted into an inducible expression vector which produced phosphoglycerate dehydrogenase as 8% of the soluble protein of E. coli. The purified protein was used to grow several different single crystal forms. One of these, with space group P2(1), appears to contain all four subunits of the tetrameric enzyme in the asymmetric unit and diffracts to sufficient resolution to allow determination of the structure of phosphoglycerate dehydrogenase.

  7. Coupling between d-3-phosphoglycerate dehydrogenase and d-2-hydroxyglutarate dehydrogenase drives bacterial l-serine synthesis

    PubMed Central

    Zhang, Wen; Zhang, Manman; Gao, Chao; Zhang, Yipeng; Ge, Yongsheng; Guo, Shiting; Guo, Xiaoting; Zhou, Zikang; Liu, Qiuyuan; Zhang, Yingxin; Ma, Cuiqing; Tao, Fei; Xu, Ping

    2017-01-01

    l-Serine biosynthesis, a crucial metabolic process in most domains of life, is initiated by d-3-phosphoglycerate (d-3-PG) dehydrogenation, a thermodynamically unfavorable reaction catalyzed by d-3-PG dehydrogenase (SerA). d-2-Hydroxyglutarate (d-2-HG) is traditionally viewed as an abnormal metabolite associated with cancer and neurometabolic disorders. Here, we reveal that bacterial anabolism and catabolism of d-2-HG are involved in l-serine biosynthesis in Pseudomonas stutzeri A1501 and Pseudomonas aeruginosa PAO1. SerA catalyzes the stereospecific reduction of 2-ketoglutarate (2-KG) to d-2-HG, responsible for the major production of d-2-HG in vivo. SerA combines the energetically favorable reaction of d-2-HG production to overcome the thermodynamic barrier of d-3-PG dehydrogenation. We identified a bacterial d-2-HG dehydrogenase (D2HGDH), a flavin adenine dinucleotide (FAD)-dependent enzyme, that converts d-2-HG back to 2-KG. Electron transfer flavoprotein (ETF) and ETF-ubiquinone oxidoreductase (ETFQO) are also essential in d-2-HG metabolism through their capacity to transfer electrons from D2HGDH. Furthermore, while the mutant with D2HGDH deletion displayed decreased growth, the defect was rescued by adding l-serine, suggesting that the D2HGDH is functionally tied to l-serine synthesis. Substantial flux flows through d-2-HG, being produced by SerA and removed by D2HGDH, ETF, and ETFQO, maintaining d-2-HG homeostasis. Overall, our results uncover that d-2-HG–mediated coupling between SerA and D2HGDH drives bacterial l-serine synthesis. PMID:28827360

  8. Exploring the clonal evolution of CD133/aldehyde-dehydrogenase-1 (ALDH1)-positive cancer stem-like cells from primary to recurrent high-grade serous ovarian cancer (HGSOC). A study of the Ovarian Cancer Therapy-Innovative Models Prolong Survival (OCTIPS) Consortium.

    PubMed

    Ruscito, Ilary; Cacsire Castillo-Tong, Dan; Vergote, Ignace; Ignat, Iulia; Stanske, Mandy; Vanderstichele, Adriaan; Ganapathi, Ram N; Glajzer, Jacek; Kulbe, Hagen; Trillsch, Fabian; Mustea, Alexander; Kreuzinger, Caroline; Benedetti Panici, Pierluigi; Gourley, Charlie; Gabra, Hani; Kessler, Mirjana; Sehouli, Jalid; Darb-Esfahani, Silvia; Braicu, Elena Ioana

    2017-07-01

    High-grade serous ovarian cancer (HGSOC) causes 80% of all ovarian cancer (OC) deaths. In this setting, the role of cancer stem-like cells (CSCs) is still unclear. In particular, the evolution of CSC biomarkers from primary (pOC) to recurrent (rOC) HGSOCs is unknown. Aim of this study was to investigate changes in CD133 and aldehyde dehydrogenase-1 (ALDH1) CSC biomarker expression in pOC and rOC HGSOCs. Two-hundred and twenty-four pOC and rOC intrapatient paired tissue samples derived from 112 HGSOC patients were evaluated for CD133 and ALDH1 expression using immunohistochemistry (IHC); pOCs and rOCs were compared for CD133 and/or ALDH1 levels. Expression profiles were also correlated with patients' clinicopathological and survival data. Some 49.1% of the patient population (55/112) and 37.5% (42/112) pOCs were CD133+ and ALDH1+ respectively. CD133+ and ALDH1+ samples were detected in 33.9% (38/112) and 36.6% (41/112) rOCs. CD133/ALDH1 coexpression was observed in 23.2% (26/112) and 15.2% (17/112) of pOCs and rOCs respectively. Pairwise analysis showed a significant shift of CD133 staining from higher (pOCs) to lower expression levels (rOCs) (p < 0.0001). Furthermore, all CD133 + pOC patients were International Federation of Gynaecology and Obstetrics (FIGO)-stage III/IV (p < 0.0001) and had significantly worse progression-free interval (PFI) (p = 0.04) and overall survival (OS) (p = 0.02). On multivariate analysis, CD133/ALDH1 coexpression in pOCs was identified as independent prognostic factor for PFI (HR: 1.64; 95% CI: 1.03-2.60; p = 0.036) and OS (HR: 1.71; 95% CI: 1.01-2.88; p = 0.045). Analysis on 52 pts patients with known somatic BRCA status revealed that BRCA mutations did not influence CSC biomarker expression. The study showed that CD133/ALDH1 expression impacts HGSOC patients' survival and first suggests that CSCs might undergo phenotypic change during the disease course similarly to non stem-like cancer cells, providing also a first

  9. Peptidyl aldehyde NK-1.8k suppresses enterovirus 71 and enterovirus 68 infection by targeting protease 3C.

    PubMed

    Wang, Yaxin; Yang, Ben; Zhai, Yangyang; Yin, Zheng; Sun, Yuna; Rao, Zihe

    2015-05-01

    Enterovirus (EV) is one of the major causative agents of hand, foot, and mouth disease in the Pacific-Asia region. In particular, EV71 causes severe central nervous system infections, and the fatality rates from EV71 infection are high. Moreover, an outbreak of respiratory illnesses caused by an emerging EV, EV68, recently occurred among over 1,000 young children in the United States and was also associated with neurological infections. Although enterovirus has emerged as a considerable global public health threat, no antiviral drug for clinical use is available. In the present work, we screened our compound library for agents targeting viral protease and identified a peptidyl aldehyde, NK-1.8k, that inhibits the proliferation of different EV71 strains and one EV68 strain and that had a 50% effective concentration of 90 nM. Low cytotoxicity (50% cytotoxic concentration, >200 μM) indicated a high selective index of over 2,000. We further characterized a single amino acid substitution inside protease 3C (3C(pro)), N69S, which conferred EV71 resistance to NK-1.8k, possibly by increasing the flexibility of the substrate binding pocket of 3C(pro). The combination of NK-1.8k and an EV71 RNA-dependent RNA polymerase inhibitor or entry inhibitor exhibited a strong synergistic anti-EV71 effect. Our findings suggest that NK-1.8k could potentially be developed for anti-EV therapy. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  10. Ethanol Metabolism by HeLa Cells Transduced with Human Alcohol Dehydrogenase Isoenzymes: Control of the Pathway by Acetaldehyde Concentration†

    PubMed Central

    Matsumoto, Michinaga; Cyganek, Izabela; Sanghani, Paresh C.; Cho, Won Kyoo; Liangpunsakul, Suthat; Crabb, David W.

    2010-01-01

    Background Human class I alcohol dehydrogenase 2 isoenzymes (encoded by the ADH1B locus) have large differences in kinetic properties; however, individuals inheriting the alleles for the different isoenzymes exhibit only small differences in alcohol elimination rates. This suggests that other cellular factors must regulate the activity of the isoenzymes. Methods The activity of the isoenzymes expressed from ADH1B*1, ADH1B*2, and ADH1B*3 cDNAs was examined in stably transduced HeLa cell lines, including lines which expressed human low Km aldehyde dehydrogenase (ALDH2). The ability of the cells to metabolize ethanol was compared with that of HeLa cells expressing rat class I ADH (HeLa-rat ADH cells), rat hepatoma (H4IIEC3) cells, and rat hepatocytes. Results The isoenzymes had similar protein half-lives in the HeLa cells. Rat hepatocytes, H4IIEC3 cells, and HeLa-rat ADH cells oxidized ethanol much faster than the cells expressing the ADH1B isoenzymes. This was not explained by high cellular NADH levels or endogenous inhibitors; but rather because the activity of the β1 and β2 ADHs were constrained by the accumulation of acetaldehyde, as shown by the increased rate of ethanol oxidation by cell lines expressing β2 ADH plus ALDH2. Conclusion The activity of the human β2 ADH isoenzyme is sensitive to inhibition by acetaldehyde, which likely limits its activity in vivo. This study emphasizes the importance of maintaining a low steady–state acetaldehyde concentration in hepatocytes during ethanol metabolism. PMID:21166830

  11. Aromatic aldehydes at the active site of aldehyde oxidoreductase from Desulfovibrio gigas: reactivity and molecular details of the enzyme-substrate and enzyme-product interaction.

    PubMed

    Correia, Hugo D; Marangon, Jacopo; Brondino, Carlos D; Moura, Jose J G; Romão, Maria J; González, Pablo J; Santos-Silva, Teresa

    2015-03-01

    Desulfovibrio gigas aldehyde oxidoreductase (DgAOR) is a mononuclear molybdenum-containing enzyme from the xanthine oxidase (XO) family, a group of enzymes capable of catalyzing the oxidative hydroxylation of aldehydes and heterocyclic compounds. The kinetic studies reported in this work showed that DgAOR catalyzes the oxidative hydroxylation of aromatic aldehydes, but not heterocyclic compounds. NMR spectroscopy studies using (13)C-labeled benzaldehyde confirmed that DgAOR catalyzes the conversion of aldehydes to the respective carboxylic acids. Steady-state kinetics in solution showed that high concentrations of the aromatic aldehydes produce substrate inhibition and in the case of 3-phenyl propionaldehyde a suicide substrate behavior. Hydroxyl-substituted aromatic aldehydes present none of these behaviors but the kinetic parameters are largely affected by the position of the OH group. High-resolution crystallographic structures obtained from single crystals of active-DgAOR soaked with benzaldehyde showed that the side chains of Phe425 and Tyr535 are important for the stabilization of the substrate in the active site. On the other hand, the X-ray data of DgAOR soaked with trans-cinnamaldehyde showed a cinnamic acid molecule in the substrate channel. The X-ray data of DgAOR soaked with 3-phenyl propionaldehyde showed clearly how high substrate concentrations inactivate the enzyme by binding covalently at the surface of the enzyme and blocking the substrate channel. The different reactivity of DgAOR versus aldehyde oxidase and XO towards aromatic aldehydes and N-heterocyclic compounds is explained on the basis of the present kinetic and structural data.

  12. Incorporation of nitric oxide donor into 1,3-dioxyxanthones leads to synergistic anticancer activity.

    PubMed

    Liu, Jie; Zhang, Cao; Wang, Huailing; Zhang, Lei; Jiang, Zhenlei; Zhang, Jianrun; Liu, Zhijun; Chen, Heru

    2018-05-10

    Fifty 1,3-dioxyxanthone nitrates (4a ∼ i-n, n = 1-6) were designed and synthesized based on molecular similarity strategy. Incorporation of nitrate into 1,3-dioxyxanthones with electron-donating groups at 6-8 position brought about synergistic anticancer effect. Among them, compound 4g-4 was confirmed the most active agent against HepG-2 cells growth with an IC 50 of 0.33 ± 0.06 μM. It dose-dependently increased intramolecular NO levels. This activity was attenuated by either NO scavenger PTIO or mitochondrial aldehyde dehydrogenase (mtADH) inhibitor PCDA. Apoptosis analysis indicated different contributions of early/late apoptosis and necrosis to cell death for different dose of 4g-4. 4g-4 arrested more cells on S phase. Results from Western Blot implied that 4g-4 regulated p53/MDM2 to promote cancer cell apoptosis. All the evidences support that 4g-4 is a promising anti-cancer agent. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  13. 9-cis Retinoic Acid is the ALDH1A1 Product that Stimulates Melanogenesis

    PubMed Central

    Paterson, Elyse K.; Ho, Hsiang; Kapadia, Rubina; Ganesan, Anand K.

    2013-01-01

    Aldehyde dehydrogenase 1A1 (ALDH1A1), an enzyme that catalyzes the conversion of lipid aldehydes to lipid carboxylic acids, plays pleiotropic roles in UV-radiation resistance, melanogenesis, and stem cell maintenance. In this study, a combination of RNAi and pharmacologic approaches were used to determine which ALDH1A1 substrates and products regulate melanogenesis. Initial studies revealed that neither the UV-induced lipid aldehyde 4-hydroxy-2-nonenal nor the ALDH1A1 product all-trans retinoic acid appreciably induced melanogenesis. In contrast, both the ALDH1A1 substrate 9-cis retinal and its corresponding product 9-cis retinoic acid potently induced the accumulation of MITF mRNA, Tyrosinase mRNA, and melanin. ALDH1A1 depletion inhibited the ability of 9-cis retinal but not 9-cis retinoic acid to stimulate melanogenesis, indicating that ALDH1A1 regulates melanogenesis by catalyzing the conversion of 9-cis retinal to 9-cis retinoic acid. The addition of potent ALDH1A inhibitors (cyanamide or Angeli’s salt) suppressed Tyrosinase and MITF mRNA accumulation in vitro and also melanin accumulation in skin equivalents, suggesting that 9-cis retinoids regulate melanogenesis in the intact epidermis. Taken together, these studies not only identify cyanamide as a potential novel treatment for hyperpigmentary disorders, but also identify 9-cis retinoic acid as a pigment stimulatory agent that may have clinical utility in the treatment of hypopigmentary disorders, such as vitiligo. PMID:23489423

  14. E-cigarettes generate high levels of aldehydes only in 'dry puff' conditions.

    PubMed

    Farsalinos, Konstantinos E; Voudris, Vassilis; Poulas, Konstantinos

    2015-08-01

    Aldehydes are emitted by electronic cigarettes due to thermal decomposition of liquid components. Although elevated levels have been reported with new-generation high-power devices, it is unclear whether they are relevant to true exposure of users (vapers) because overheating produces an unpleasant taste, called a dry puff, which vapers learn to avoid. The aim was to evaluate aldehyde emissions at different power levels associated with normal and dry puff conditions. Two customizable atomizers were prepared so that one (A1) had a double wick, resulting in high liquid supply and lower chance of overheating at high power levels, while the other (A2) was a conventional setup (single wick). Experienced vapers took 4-s puffs at 6.5 watts (W), 7.5 W, 9 W and 10 W power levels with both atomizers and were asked to report whether dry puffs were generated. The atomizers were then attached to a smoking machine and aerosol was trapped. Clinic office and analytical chemistry laboratory in Greece. Seven experienced vapers. Aldehyde levels were measured in the aerosol. All vapers identified dry puff conditions at 9 W and 10 W with A2. A1 did not lead to dry puffs at any power level. Minimal amounts of aldehydes per 10 puffs were found at all power levels with A1 (up to 11.3 µg for formaldehyde, 4.5 µg for acetaldehyde and 1.0 µg for acrolein) and at 6.5 W and 7.5 W with A2 (up to 3.7 µg for formaldehyde, 0.8 µg for acetaldehyde and 1.3 µg for acrolein). The levels were increased by 30 to 250 times in dry puff conditions (up to 344.6 µg for formaldehyde, 206.3 µg for acetaldehyde and 210.4 µg for acrolein, P < 0.001), while acetone was detected only in dry puff conditions (up to 22.5 µg). Electronic cigarettes produce high levels of aldehyde only in dry puff conditions, in which the liquid overheats, causing a strong unpleasant taste that e-cigarette users detect and avoid. Under normal vaping conditions aldehyde emissions are

  15. Aldehyde-alcohol dehydrogenase and/or thiolase overexpression coupled with CoA transferase downregulation lead to higher alcohol titers and selectivity in Clostridium acetobutylicum fermentations.

    PubMed

    Sillers, Ryan; Al-Hinai, Mohab Ali; Papoutsakis, Eleftherios T

    2009-01-01

    Metabolic engineering (ME) of Clostridium acetobutylicum has led to increased solvent (butanol, acetone, and ethanol) production and solvent tolerance, thus demonstrating that further efforts have the potential to create strains of industrial importance. With recently developed ME tools, it is now possible to combine genetic modifications and thus implement more advanced ME strategies. We have previously shown that antisense RNA (asRNA)-based downregulation of CoA transferase (CoAT, the first enzyme in the acetone-formation pathway) results in increased butanol to acetone selectivity, but overall reduced butanol yields and titers. In this study the alcohol/aldehyde dehydrogenase (aad) gene (encoding the bifunctional protein AAD responsible for butanol and ethanol production from butyryl-CoA and acetyl-CoA, respectively) was expressed from the phosphotransbutyrylase (ptb) promoter to enhance butanol formation and selectivity, while CoAT downregulation was used to minimize acetone production. This led to early production of high alcohol (butanol plus ethanol) titers, overall solvent titers of 30 g/L, and a higher alcohol/acetone ratio. Metabolic flux analysis revealed the likely depletion of butyryl-CoA. In order to increase then the flux towards butyryl-CoA, we examined the impact of thiolase (THL, thl) overexpression. THL converts acetyl-CoA to acetoacetyl-CoA, the first step of the pathway from acetyl-CoA to butyryl-CoA, and thus, combining thl overexpression with aad overexpression decreased, as expected, acetate and ethanol production while increasing acetone and butyrate formation. thl overexpression in strains with asRNA CoAT downregulation did not significantly alter product formation thus suggesting that a more complex metabolic engineering strategy is necessary to enhance the intracellular butyryl-CoA pool and reduce the acetyl-CoA pool in order to achieve improved butanol titers and selectivity.

  16. Mycophenolic acid exposure and complement fraction C3 influence inosine 5'-monophosphate dehydrogenase activity in systemic lupus erythematosus.

    PubMed

    Mino, Yasuaki; Naito, Takafumi; Shimoyama, Kumiko; Ogawa, Noriyoshi; Kawakami, Junichi

    2017-07-01

    Background Mycophenolate mofetil has recently been reported to be effective against systemic lupus erythematosus. The influence of the pharmacokinetics of mycophenolic acid, the active form of mycophenolate mofetil and the major inactive mycophenolic acid phenolic glucuronide on the activity of the target enzyme inosine 5'-monophosphate dehydrogenase, is expected to be revealed. The aim of this study was to identify the factors associated with inosine 5'-monophosphate dehydrogenase activity in systemic lupus erythematosus patients. Methods Fifty systemic lupus erythematosus patients in remission maintenance phase (29 received mycophenolate mofetil [MMF+] and 21 did not [MMF-]) were enrolled. Median and interquartile range of dose of mycophenolate mofetil were 1500 and 1000-1500 mg/day, respectively. Stepwise multiple linear regression analysis was performed to assess the dependence between inosine 5'-monophosphate dehydrogenase activity and 25 predictor values including predose plasma concentrations of free mycophenolic acid and mycophenolic acid phenolic glucuronide. Results Median and interquartile range of predose total plasma concentrations of mycophenolic acid and mycophenolic acid phenolic glucuronide were 2.73 and 1.43-5.73 and 25.5 and 13.1-54.7  µg/mL, respectively. Predose inosine 5'-monophosphate dehydrogenase activity was significantly higher in MMF+ than MMF- patients (median 38.3 and 20.6 nmoL xanthosine 5'-monophosphate/g haemoglobin/h, P<0.01). The plasma concentration of free mycophenolic acid phenolic glucuronide, complement fraction C3 and body weight were significant predictors accounting for interindividual variability in the inosine 5'-monophosphate dehydrogenase activity (adjusted R 2  = 0.52, P < 0.01) in a multivariate analysis. Conclusions Predose inosine 5'-monophosphate dehydrogenase activity was higher in systemic lupus erythematosus patients receiving mycophenolate mofetil therapy. Inosine 5'-monophosphate dehydrogenase

  17. Aldehyde dedydrogenase-2 plays a beneficial role in ameliorating chronic alcohol-induced hepatic steatosis and inflammation through regulation of autophagy.

    PubMed

    Guo, Rui; Xu, Xihui; Babcock, Sara A; Zhang, Yingmei; Ren, Jun

    2015-03-01

    Mitochondrial aldehyde dehydrogenase (ALDH2) plays a critical role in the detoxification of the ethanol metabolite acetaldehyde. This study was designed to examine the impact of global ALDH2 overexpression on alcohol-induced hepatic steatosis. Wild type Friend virus B (FVB) and ALDH2 transgenic mice were placed on a 4% alcohol or control diet for 12 weeks. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin and cholesterol, hepatic triglyceride, steatosis, fat metabolism-related proteins, pro-inflammatory cytokines, glutathione (GSH), oxidized glutathione (GSSG), autophagy and autophagy signalling were examined. The role of autophagy was evaluated in alcohol dehydrogenase 1 (ADH1)-transfected human hepatocellular liver carcinoma cells (VA-13) treated with or without the autophagy inducer rapamycin and lysosomal inhibitors. Chronic alcohol intake led to elevated AST-, ALT-levels, bilirubin, AST/ALT ratio, cholesterol, hepatic triglycerides and hepatic fat deposition as evidenced by H&E and Oil Red O staining. Hepatic fat deposition was associated with disturbed levels of fat metabolism-related proteins (fatty acid synthase, SCD1), upregulated interleukin-6, TNF-α, cyclooxygenase, oxidative stress, and loss of autophagy, effects which were attenuated or ablated by the ALDH2 transgene. Moreover, ethanol (100 mM) and acetaldehyde (100 and 500 μM) increased levels of IL-6 and IFN-γ, and suppressed autophagy in VA-13 cells, effects which were markedly alleviated by rapamycin. In addition, lysosomal inhibitors mimicked ethanol-induced p62 accumulation with little additive effect with ethanol. Ethanol significantly suppressed LC3 conversion in the presence of lysosomal inhibitors. In summary, our results revealed that ALDH2 plays a beneficial role in ameliorating chronic alcohol intake-induced hepatic steatosis and inflammation through regulation of autophagy. Copyright © 2014 European Association for the Study of the Liver

  18. DIFFERENTIATING THE TOXICITY OF CARCINOGENIC ALDEHYDES FROM NONCARCINOGENIC ALDEHYDES IN THE RAT NOSE USING CDNA ARRAYS

    EPA Science Inventory

    Differentiating the Toxicity of Carcinogenic Aldehydes from Noncarcinogenic Aldehydes in the Rat Nose Using cDNA Arrays.

    Formaldehyde is a widely used aldehyde in many industrial settings, the tanning process, household products, and is a contaminant in cigarette smoke. H...

  19. Chirped Pulse-Fourier Transform Microwave Spectroscopy of Ethyl 3-METHYL-3-PHENYLGLYCIDATE (strawberry Aldehyde)

    NASA Astrophysics Data System (ADS)

    Shipman, Steven T.; Neill, Justin L.; Muckle, Matt T.; Suenram, Richard D.; Pate, Brooks H.

    2009-06-01

    Strawberry aldehyde (C_{12} O_3 H_{14}), a common artificial flavoring compound, has two non-interconvertible conformational families defined by the relative stereochemistry around its epoxide carbons. In one family, referred to as the trans because the two large substituents (a phenyl ring and an ethyl ester) are on opposite sides of the epoxide ring, these two substituents are unable to interact with each other. However, in the cis family, there is a long-range interaction that is difficult to accurately capture in electronic structure calculations. Three trans and two cis conformations have been assigned by broadband chirped pulse Fourier transform microwave spectroscopy, along with the C-13 isotopomers in natural abundance for one conformer from each of the families. The agreement of the rotational constants, relative dipole moments, and relative energies between theory and experiment is excellent, even at relatively crude levels of theory, for the trans family, but is quite poor for the cis conformers. In addition, due to the reactivity of strawberry aldehyde and the high temperature to which it must be heated to yield a suitable vapor pressure, several decomposition products have been assigned, and more, as of yet unassigned, are likely to be present. This project demonstrates some of the challenges in performing large-molecule rotational spectroscopy.

  20. Spotting optimization for oligo microarrays on aldehyde-glass.

    PubMed

    Dawson, Erica D; Reppert, Amy E; Rowlen, Kathy L; Kuck, Laura R

    2005-06-15

    Low-density microarrays that utilize short oligos (<100 nt) for capture are highly attractive for use in diagnostic applications, yet these experiments require strict quality control and meticulous reproducibility. However, a survey of current literature indicates vast inconsistencies in the spotting and processing procedures. In this study, spotting and processing protocols were optimized for aldehyde-functionalized glass substrates. Figures of merit were developed for quantitative comparison of spot quality and reproducibility. Experimental variables examined included oligo concentration in the spotting buffer, composition of the spotting buffer, postspotting "curing" conditions, and postspotting wash conditions. Optimized conditions included the use of 3-4 microM oligo in a 3x standard saline citrate/0.05% sodium dodecyl sulfate/0.001% (3-[(3-cholamidopropyl) dimethylammonia]-1-propane sulfonate) spotting buffer, 24-h postspotting reaction at 100% relative humidity, and a four-step wash procedure. Evaluation of six types of aldehyde-functionalized glass substrates indicated that those manufactured by CEL Associates, Inc. yield the highest oligo coverage.

  1. Efficient androst-1,4-diene-3,17-dione production by co-expressing 3-ketosteroid-Δ1 -dehydrogenase and catalase in Bacillus subtilis.

    PubMed

    Shao, M; Sha, Z; Zhang, X; Rao, Z; Xu, M; Yang, T; Xu, Z; Yang, S

    2017-01-01

    3-ketosteroid-Δ 1 -dehydrogenase (KSDD), a flavin adenine dinucleotide (FAD)-dependent enzyme involved in sterol metabolism, specifically catalyses the conversion of androst-4-ene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD). However, the low KSDD activity and the toxic effects of hydrogen peroxide (H 2 O 2 ) generated during the biotransformation of AD to ADD with FAD regeneration hinder its application on AD conversion. The aim of this work was to improve KSDD activity and eliminate the toxic effects of the generated H 2 O 2 to enhance ADD production. The ksdd gene obtained from Mycobacterium neoaurum JC-12 was codon-optimized to increase its expression level in Bacillus subtilis, and the KSDD activity reached 12·3 U mg -1 , which was sevenfold of that of codon-unoptimized gene. To improve AD conversion, catalase was co-expressed with KSDD in B. subtilis 168/pMA5-ksdd opt -katA to eliminate the toxic effects of H 2 O 2 generated during AD conversion. Finally, under optimized bioconversion conditions, fed-batch strategy was carried out and the ADD yield improved to 8·76 g l -1 . This work demonstrates the potential to improve enzyme activity by codon-optimization and eliminate the toxic effects of H 2 O 2 by co-expressing catalase. This study showed the highest ADD productivity ever reported and provides a promising strain for efficient ADD production in the pharmaceutical industry. © 2016 The Society for Applied Microbiology.

  2. Deciphering the Origin, Evolution, and Physiological Function of the Subtelomeric Aryl-Alcohol Dehydrogenase Gene Family in the Yeast Saccharomyces cerevisiae.

    PubMed

    Yang, Dong-Dong; de Billerbeck, Gustavo M; Zhang, Jin-Jing; Rosenzweig, Frank; Francois, Jean-Marie

    2018-01-01

    Homology searches indicate that Saccharomyces cerevisiae strain BY4741 contains seven redundant genes that encode putative aryl-alcohol dehydrogenases (AAD). Yeast AAD genes are located in subtelomeric regions of different chromosomes, and their functional role(s) remain enigmatic. Here, we show that two of these genes, AAD4 and AAD14 , encode functional enzymes that reduce aliphatic and aryl-aldehydes concomitant with the oxidation of cofactor NADPH, and that Aad4p and Aad14p exhibit different substrate preference patterns. Other yeast AAD genes are undergoing pseudogenization. The 5' sequence of AAD15 has been deleted from the genome. Repair of an AAD3 missense mutation at the catalytically essential Tyr 73 residue did not result in a functional enzyme. However, ancestral-state reconstruction by fusing Aad6 with Aad16 and by N-terminal repair of Aad10 restores NADPH-dependent aryl-alcohol dehydrogenase activities. Phylogenetic analysis indicates that AAD genes are narrowly distributed in wood-saprophyte fungi and in yeast that occupy lignocellulosic niches. Because yeast AAD genes exhibit activity on veratraldehyde, cinnamaldehyde, and vanillin, they could serve to detoxify aryl-aldehydes released during lignin degradation. However, none of these compounds induce yeast AAD gene expression, and Aad activities do not relieve aryl-aldehyde growth inhibition. Our data suggest an ancestral role for AAD genes in lignin degradation that is degenerating as a result of yeast's domestication and use in brewing, baking, and other industrial applications. IMPORTANCE Functional characterization of hypothetical genes remains one of the chief tasks of the postgenomic era. Although the first Saccharomyces cerevisiae genome sequence was published over 20 years ago, 22% of its estimated 6,603 open reading frames (ORFs) remain unverified. One outstanding example of this category of genes is the enigmatic seven-member AAD family. Here, we demonstrate that proteins encoded by two

  3. Deciphering the Origin, Evolution, and Physiological Function of the Subtelomeric Aryl-Alcohol Dehydrogenase Gene Family in the Yeast Saccharomyces cerevisiae

    PubMed Central

    de Billerbeck, Gustavo M.; Zhang, Jin-jing; Rosenzweig, Frank

    2017-01-01

    ABSTRACT Homology searches indicate that Saccharomyces cerevisiae strain BY4741 contains seven redundant genes that encode putative aryl-alcohol dehydrogenases (AAD). Yeast AAD genes are located in subtelomeric regions of different chromosomes, and their functional role(s) remain enigmatic. Here, we show that two of these genes, AAD4 and AAD14, encode functional enzymes that reduce aliphatic and aryl-aldehydes concomitant with the oxidation of cofactor NADPH, and that Aad4p and Aad14p exhibit different substrate preference patterns. Other yeast AAD genes are undergoing pseudogenization. The 5′ sequence of AAD15 has been deleted from the genome. Repair of an AAD3 missense mutation at the catalytically essential Tyr73 residue did not result in a functional enzyme. However, ancestral-state reconstruction by fusing Aad6 with Aad16 and by N-terminal repair of Aad10 restores NADPH-dependent aryl-alcohol dehydrogenase activities. Phylogenetic analysis indicates that AAD genes are narrowly distributed in wood-saprophyte fungi and in yeast that occupy lignocellulosic niches. Because yeast AAD genes exhibit activity on veratraldehyde, cinnamaldehyde, and vanillin, they could serve to detoxify aryl-aldehydes released during lignin degradation. However, none of these compounds induce yeast AAD gene expression, and Aad activities do not relieve aryl-aldehyde growth inhibition. Our data suggest an ancestral role for AAD genes in lignin degradation that is degenerating as a result of yeast's domestication and use in brewing, baking, and other industrial applications. IMPORTANCE Functional characterization of hypothetical genes remains one of the chief tasks of the postgenomic era. Although the first Saccharomyces cerevisiae genome sequence was published over 20 years ago, 22% of its estimated 6,603 open reading frames (ORFs) remain unverified. One outstanding example of this category of genes is the enigmatic seven-member AAD family. Here, we demonstrate that proteins encoded

  4. Genetics Home Reference: isobutyryl-CoA dehydrogenase deficiency

    MedlinePlus

    ... dehydrogenase deficiency Orphanet: Isobutyryl-CoA dehydrogenase deficiency Screening, Technology and Research in Genetics Patient Support and Advocacy Resources (3 links) Children's Cardiomyopathy Foundation CLIMB (Children Living with Inherited Metabolic ...

  5. Semi-catalytic reduction of secondary amides to imines and aldehydes.

    PubMed

    Lee, Sun-Hwa; Nikonov, Georgii I

    2014-06-21

    Secondary amides can be reduced by silane HSiMe2Ph into imines and aldehydes by a two-stage process involving prior conversion of amides into iminoyl chlorides followed by catalytic reduction mediated by the ruthenium complex [Cp(i-Pr3P)Ru(NCCH3)2]PF6 (1). Alkyl and aryl amides bearing halogen, ketone, and ester groups were converted with moderate to good yields under mild reaction conditions to the corresponding imines and aldehydes. This procedure does not work for substrates bearing the nitro-group and fails for heteroaromatic amides. In the case of cyano substituted amides, the cyano group is reduced to imine.

  6. Analysis of aldehydes in human exhaled breath condensates by in-tube SPME-HPLC.

    PubMed

    Wang, ShuLing; Hu, Sheng; Xu, Hui

    2015-11-05

    In this paper, polypyrrole/graphene (PPy/G) composite coating was prepared by a facile electrochemical polymerization strategy on the inner surface of a stainless steel (SS) tube. Based on the coating tube, a novel online in-tube solid-phase microextraction -high performance liquid chromatography (IT-SPME-HPLC) was developed and applied for the extraction of aldehydes in the human exhaled breath condensates (EBC). The hybrid PPy/G nanocomposite exhibits remarkable chemical and mechanical stability, high selectivity, and satisfactory extraction performance toward aldehyde compounds. Moreover, the proposed online IT-SPME-HPLC method possesses numerous superiorities, such as time and cost saving, process simplicity, high precision and sensitivity. Some parameters related to extraction efficiency were optimized systematically. Under the optimal conditions, the recoveries of the aldehyde compounds at three spiked concentration levels varied in the range of 85%-117%. Good linearity was obtained with excellent correlation coefficients (R(2)) being larger than 0.994. The relative standard deviations (n = 5) of the method ranged from 1.8% to 11.3% and the limits of detection were between 2.3 and 3.3 nmol L(-1). The successful application of the proposed method in human EBC indicated that it is a promising approach for the determination of trace aldehyde metabolites in complex EBC samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. First general methods toward aldehyde enolphosphates.

    PubMed

    Barthes, Nicolas; Grison, Claude

    2012-02-01

    We herein report two innovative methods toward aldehyde enolphosphates and the first saccharidic aldehyde enolphosphates. Aldehyde enolphosphate function is worthwhile to be considered as a good phosphoenolpyruvate analogue. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Digitalis metabolism and human liver alcohol dehydrogenase.

    PubMed Central

    Frey, W A; Vallee, B L

    1980-01-01

    Human liver alcohol dehydrogenase (alcohol: NAD" oxidoreductase, EC 1.1.1.1) catalyzes the oxidation of the 3 beta-OH group of digitoxigenin, digoxigenin, and gitoxigenin to their 3-keto derivatives, which have been characterized by high performance liquid chromatography and mass spectrometry. These studies have identified human liver alcohol dehydrogenase as the unknown NAD(H)-dependent liver enzyme specific for the free hydroxyl group at C3 of the cardiac genins; this hydroxyl is the critical site of the genins' enzymatic oxidation and concomitant pharmacological inactivation in humans. Several kinetic approaches have demonstrated that ethanol and the pharmacologically active components of the digitalis glycosides are oxidized with closely similar kcat/Km values at the same site on human liver alcohol dehydrogenase, for which they compete. Human liver alcohol dehydrogenase thereby becomes an important biochemical link in the metabolism, pharmacology, and toxicology of ethanol and these glycosides, structurally unrelated agents that are both used widely. Both the competition of ethanol with these cardiac sterols and the narrow margin of safety in the therapeutic use of digitalis derivatives would seem to place at increased risk those individuals who receive digitalis and simultaneously consume large amounts of ethanol or whose alcohol dehydrogenase function is impaired. PMID:6987673

  9. Amine dehydrogenases: efficient biocatalysts for the reductive amination of carbonyl compounds

    PubMed Central

    Mutti, Francesco G.

    2017-01-01

    Amines constitute the major targets for the production of a plethora of chemical compounds that have applications in the pharmaceutical, agrochemical and bulk chemical industries. However, the asymmetric synthesis of α-chiral amines with elevated catalytic efficiency and atom economy is still a very challenging synthetic problem. Here, we investigated the biocatalytic reductive amination of carbonyl compounds employing a rising class of enzymes for amine synthesis: amine dehydrogenases (AmDHs). The three AmDHs from this study – operating in tandem with a formate dehydrogenase from Candida boidinii (Cb-FDH) for the recycling of the nicotinamide coenzyme – performed the efficient amination of a range of diverse aromatic and aliphatic ketones and aldehydes with up to quantitative conversion and elevated turnover numbers (TONs). Moreover, the reductive amination of prochiral ketones proceeded with perfect stereoselectivity, always affording the (R)-configured amines with more than 99% enantiomeric excess. The most suitable amine dehydrogenase, the optimised catalyst loading and the required reaction time were determined for each substrate. The biocatalytic reductive amination with this dual-enzyme system (AmDH–Cb-FDH) possesses elevated atom efficiency as it utilizes the ammonium formate buffer as the source of both nitrogen and reducing equivalents. Inorganic carbonate is the sole by-product. PMID:28663713

  10. Amine dehydrogenases: efficient biocatalysts for the reductive amination of carbonyl compounds.

    PubMed

    Knaus, Tanja; Böhmer, Wesley; Mutti, Francesco G

    2017-01-21

    Amines constitute the major targets for the production of a plethora of chemical compounds that have applications in the pharmaceutical, agrochemical and bulk chemical industries. However, the asymmetric synthesis of α-chiral amines with elevated catalytic efficiency and atom economy is still a very challenging synthetic problem. Here, we investigated the biocatalytic reductive amination of carbonyl compounds employing a rising class of enzymes for amine synthesis: amine dehydrogenases (AmDHs). The three AmDHs from this study - operating in tandem with a formate dehydrogenase from Candida boidinii (Cb-FDH) for the recycling of the nicotinamide coenzyme - performed the efficient amination of a range of diverse aromatic and aliphatic ketones and aldehydes with up to quantitative conversion and elevated turnover numbers (TONs). Moreover, the reductive amination of prochiral ketones proceeded with perfect stereoselectivity, always affording the ( R )-configured amines with more than 99% enantiomeric excess. The most suitable amine dehydrogenase, the optimised catalyst loading and the required reaction time were determined for each substrate. The biocatalytic reductive amination with this dual-enzyme system (AmDH-Cb-FDH) possesses elevated atom efficiency as it utilizes the ammonium formate buffer as the source of both nitrogen and reducing equivalents. Inorganic carbonate is the sole by-product.

  11. OsHSD1, a hydroxysteroid dehydrogenase, is involved in cuticle formation and lipid homeostasis in rice.

    PubMed

    Zhang, Zhe; Cheng, Zhi-Jun; Gan, Lu; Zhang, Huan; Wu, Fu-Qing; Lin, Qi-Bing; Wang, Jiu-Lin; Wang, Jie; Guo, Xiu-Ping; Zhang, Xin; Zhao, Zhi-Chao; Lei, Cai-Lin; Zhu, Shan-Shan; Wang, Chun-Ming; Wan, Jian-Min

    2016-08-01

    Cuticular wax, a hydrophobic layer on the surface of all aerial plant organs, has essential roles in plant growth and survival under various environments. Here we report a wax-deficient rice mutant oshsd1 with reduced epicuticular wax crystals and thicker cuticle membrane. Quantification of the wax components and fatty acids showed elevated levels of very-long-chain fatty acids (VLCFAs) and accumulation of soluble fatty acids in the leaves of the oshsd1 mutant. We determined the causative gene OsHSD1, a member of the short-chain dehydrogenase reductase family, through map-based cloning. It was ubiquitously expressed and responded to cold stress and exogenous treatments with NaCl or brassinosteroid analogs. Transient expression of OsHSD1-tagged green fluorescent protein revealed that OsHSD1 localized to both oil bodies and endoplasmic reticulum (ER). Dehydrogenase activity assays demonstrated that OsHSD1 was an NAD(+)/NADP(+)-dependent sterol dehydrogenase. Furthermore, OsHSD1 mutation resulted in faster protein degradation, but had no effect on the dehydrogenase activity. Together, our data indicated that OsHSD1 plays a specialized role in cuticle formation and lipid homeostasis, probably by mediating sterol signaling. This work provides new insights into oil-body associated proteins involved in wax and lipid metabolism. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Determination of linear aliphatic aldehydes in heavy metal containing waters by high-performance liquid chromatography using 2,4-dinitrophenylhydrazine derivatization.

    PubMed

    Lin, Yi-Liang; Wang, Po-Yen; Hsieh, Ling-Ling; Ku, Kuan-Hsuan; Yeh, Yun-Tai; Wu, Chien-Hou

    2009-09-04

    A simple and sensitive method is described for the determination of picomolar amounts of C(1)-C(9) linear aliphatic aldehydes in waters containing heavy metal ions. In this method, aldehydes were first derivatized with 2,4-dinitrophenylhydrazine (DNPH) at optimized pH 1.8 for 30 min and analyzed by HPLC with UV detector at 365 nm. Factors affecting the derivatization reaction of aldehydes and DNPH were investigated. Cupric ion, an example of heavy metals, is a common oxidative reagent, which may oxidize DNPH and greatly interfere with the determination of aldehydes. EDTA was used to effectively mask the interferences by heavy metal ions. The method detection limits for direct injection of derivatized most aldehydes except formaldehyde were of the order of 7-28 nM. The detection limit can be further lowered by using off-line C(18) adsorption cartridge enrichment. The recoveries of C(1)-C(9) aldehydes were 93-115% with a relative standard deviation of 3.6-8.1% at the 0.1 microM level for aldehydes. The HPLC-DNPH method has been applied for determining aldehyde photoproducts from Cu(II)-amino acid complex systems.

  13. Effects of a 3β-hydroxysteroid Dehydrogenase Inhibitor, Trilostane, on the Fathead Minnow Reproductive Axis

    EPA Science Inventory

    A number of environmental contaminants and plant flavonoid compounds have been shown to inhibit the activity of 3β-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerase (3β-HSD). Because 3β-HSD plays a critical role in steroid hormone synthesis, inhibition of 3β-HSD represents a potentia...

  14. The first mammalian aldehyde oxidase crystal structure: insights into substrate specificity.

    PubMed

    Coelho, Catarina; Mahro, Martin; Trincão, José; Carvalho, Alexandra T P; Ramos, Maria João; Terao, Mineko; Garattini, Enrico; Leimkühler, Silke; Romão, Maria João

    2012-11-23

    Aldehyde oxidases have pharmacological relevance, and AOX3 is the major drug-metabolizing enzyme in rodents. The crystal structure of mouse AOX3 with kinetics and molecular docking studies provides insights into its enzymatic characteristics. Differences in substrate and inhibitor specificities can be rationalized by comparing the AOX3 and xanthine oxidase structures. The first aldehyde oxidase structure represents a major advance for drug design and mechanistic studies. Aldehyde oxidases (AOXs) are homodimeric proteins belonging to the xanthine oxidase family of molybdenum-containing enzymes. Each 150-kDa monomer contains a FAD redox cofactor, two spectroscopically distinct [2Fe-2S] clusters, and a molybdenum cofactor located within the protein active site. AOXs are characterized by broad range substrate specificity, oxidizing different aldehydes and aromatic N-heterocycles. Despite increasing recognition of its role in the metabolism of drugs and xenobiotics, the physiological function of the protein is still largely unknown. We have crystallized and solved the crystal structure of mouse liver aldehyde oxidase 3 to 2.9 Å. This is the first mammalian AOX whose structure has been solved. The structure provides important insights into the protein active center and further evidence on the catalytic differences characterizing AOX and xanthine oxidoreductase. The mouse liver aldehyde oxidase 3 three-dimensional structure combined with kinetic, mutagenesis data, molecular docking, and molecular dynamics studies make a decisive contribution to understand the molecular basis of its rather broad substrate specificity.

  15. Succinic Semialdehyde Dehydrogenase: Biochemical–Molecular–Clinical Disease Mechanisms, Redox Regulation, and Functional Significance

    PubMed Central

    Kim, Kyung-Jin; Pearl, Phillip L.; Jensen, Kimmo; Snead, O. Carter; Malaspina, Patrizia; Jakobs, Cornelis

    2011-01-01

    Abstract Succinic semialdehyde dehydrogenase (SSADH; aldehyde dehydrogenase 5a1, ALDH5A1; E.C. 1.2.1.24; OMIM 610045, 271980) deficiency is a rare heritable disorder that disrupts the metabolism of the inhibitory neurotransmitter 4-aminobutyric acid (GABA). Identified in conjunction with increased urinary excretion of the GABA analog gamma-hydroxybutyric acid (GHB), numerous patients have been identified worldwide and the autosomal-recessive disorder has been modeled in mice. The phenotype is one of nonprogressive neurological dysfunction in which seizures may be prominently displayed. The murine model is a reasonable phenocopy of the human disorder, yet the severity of the seizure disorder in the mouse exceeds that observed in SSADH-deficient patients. Abnormalities in GABAergic and GHBergic neurotransmission, documented in patients and mice, form a component of disease pathophysiology, although numerous other disturbances (metabolite accumulations, myelin abnormalities, oxidant stress, neurosteroid depletion, altered bioenergetics, etc.) are also likely to be involved in developing the disease phenotype. Most recently, the demonstration of a redox control system in the SSADH protein active site has provided new insights into the regulation of SSADH by the cellular oxidation/reduction potential. The current review summarizes some 30 years of research on this protein and disease, addressing pathological mechanisms in human and mouse at the protein, metabolic, molecular, and whole-animal level. Antioxid. Redox Signal. 15, 691–718. PMID:20973619

  16. Expression of a heat-stable NADPH-dependent alcohol dehydrogenase in Caldicellulosiruptor bescii results in furan aldehyde detoxification

    DOE PAGES

    Chung, Daehwan; Verbeke, Tobin J.; Cross, Karissa L.; ...

    2015-07-22

    Compounds such as furfural and 5-hydroxymethylfurfural (5-HMF) are generated through the dehydration of xylose and glucose, respectively, during dilute-acid pretreatment of lignocellulosic biomass and are also potent microbial growth and fermentation inhibitors. The enzymatic reduction of these furan aldehydes to their corresponding, and less toxic, alcohols is an engineering approach that has been successfully implemented in both Saccharomyces cerevisiae and ethanologenicEscherichia coli, but has not yet been investigated in thermophiles relevant to biofuel production through consolidated bioprocessing (CBP). Developing CBP-relevant biocatalysts that are either naturally resistant to such inhibitors, or are amenable to engineered resistance, is therefore, an important componentmore » in making biofuels production from lignocellulosic biomass feasible.« less

  17. Synthesis of robalzotan, ebalzotan, and rotigotine precursors via the stereoselective multienzymatic cascade reduction of α,β-unsaturated aldehydes.

    PubMed

    Brenna, Elisabetta; Gatti, Francesco G; Malpezzi, Luciana; Monti, Daniela; Parmeggiani, Fabio; Sacchetti, Alessandro

    2013-05-17

    A stereoselective synthesis of bicyclic primary or secondary amines, based on tetralin or chroman structural moieties, is reported. These amines are precursors of important active pharmaceutical ingredients such as rotigotine (Neupro), robalzotan, and ebalzotan. The key step is based on a multienzymatic reduction of an α,β-unsaturated aldehyde or ketone to give the saturated primary or secondary alcohol, in a high yield and with a high ee. The catalytic system consists of the combination of an ene-reductase (ER; i.e., OYE2 or OYE3 belonging to the Old Yellow Enzyme family) with an alcohol dehydrogenase (ADH), applying the in situ substrate feeding product removal technology. By this system the formation of the allylic alcohol side product and the racemization of the chirally unstable α-substituted aldehyde intermediate are minimized. The primary alcohols were elaborated via a Curtius rearrangement. The combination of OYE2 with a Prelog or an anti-Prelog ADH allowed the preparation of the secondary alcohols with ee > 99% and de > 87%. The absolute configuration of the primary amines was unambiguously assigned by comparison with authentic samples. The stereochemistry of secondary alcohols was assigned by X-ray crystal structure and NMR analysis of Mosher esters.

  18. Olfactory sensitivity for sperm-attractant aromatic aldehydes: a comparative study in human subjects and spider monkeys.

    PubMed

    Kjeldmand, Luna; Salazar, Laura Teresa Hernandez; Laska, Matthias

    2011-01-01

    Using a three-alternative forced-choice ascending staircase procedure, we determined olfactory detection thresholds in 20 human subjects for seven aromatic aldehydes and compared them to those of four spider monkeys tested in parallel using an operant conditioning paradigm. With all seven odorants, both species detected concentrations <1 ppm, and with several odorants single individuals of both species even discriminated concentrations <1 ppb from the solvent. No generalizable species differences in olfactory sensitivity were found despite marked differences in neuroanatomical and genetic features. The across-odorant patterns of sensitivity correlated significantly between humans and spider monkeys, and both species were more sensitive to bourgeonal than to lilial, cyclamal, canthoxal, helional, lyral, and 3-phenylpropanal. No significant correlation between presence/absence of an oxygen-containing moiety attached to the benzene ring or presence/absence of an additional alkyl group next to the functional aldehyde group, and olfactory sensitivity was found in any of the species. However, the presence of a tertiary butyl group in para position (relative to the functional aldehyde group) combined with a lack of an additional alkyl group next to the functional aldehyde group may be responsible for the finding that both species were most sensitive to bourgeonal.

  19. CYTOKININ OXIDASE/DEHYDROGENASE3 Maintains Cytokinin Homeostasis during Root and Nodule Development in Lotus japonicus1[OPEN

    PubMed Central

    Heckmann, Anne B.; Kelly, Simon

    2016-01-01

    Cytokinins are required for symbiotic nodule development in legumes, and cytokinin signaling responses occur locally in nodule primordia and in developing nodules. Here, we show that the Lotus japonicus Ckx3 cytokinin oxidase/dehydrogenase gene is induced by Nod factor during the early phase of nodule initiation. At the cellular level, pCkx3::YFP reporter-gene studies revealed that the Ckx3 promoter is active during the first cortical cell divisions of the nodule primordium and in growing nodules. Cytokinin measurements in ckx3 mutants confirmed that CKX3 activity negatively regulates root cytokinin levels. Particularly, tZ and DHZ type cytokinins in both inoculated and uninoculated roots were elevated in ckx3 mutants, suggesting that these are targets for degradation by the CKX3 cytokinin oxidase/dehydrogenase. The effect of CKX3 on the positive and negative roles of cytokinin in nodule development, infection and regulation was further clarified using ckx3 insertion mutants. Phenotypic analysis indicated that ckx3 mutants have reduced nodulation, infection thread formation and root growth. We also identify a role for cytokinin in regulating nodulation and nitrogen fixation in response to nitrate as ckx3 phenotypes are exaggerated at increased nitrate levels. Together, these findings show that cytokinin accumulation is tightly regulated during nodulation in order to balance the requirement for cell divisions with negative regulatory effects of cytokinin on infection events and root development. PMID:26644503

  20. Human dehydrogenase/reductase (SDR family) member 11 is a novel type of 17β-hydroxysteroid dehydrogenase.

    PubMed

    Endo, Satoshi; Miyagi, Namiki; Matsunaga, Toshiyuki; Hara, Akira; Ikari, Akira

    2016-03-25

    We report characterization of a member of the short-chain dehydrogenase/reductase superfamily encoded in a human gene, DHRS11. The recombinant protein (DHRS11) efficiently catalyzed the conversion of the 17-keto group of estrone, 4- and 5-androstenes and 5α-androstanes into their 17β-hydroxyl metabolites with NADPH as a coenzyme. In contrast, it exhibited reductive 3β-hydroxysteroid dehydrogenase activity toward 5β-androstanes, 5β-pregnanes, 4-pregnenes and bile acids. Additionally, DHRS11 reduced α-dicarbonyls (such as diacetyl and methylglyoxal) and alicyclic ketones (such as 1-indanone and loxoprofen). The enzyme activity was inhibited in a mixed-type manner by flavonoids, and competitively by carbenoxolone, glycyrrhetinic acid, zearalenone, curcumin and flufenamic acid. The expression of DHRS11 mRNA was observed widely in human tissues, most abundantly in testis, small intestine, colon, kidney and cancer cell lines. Thus, DHRS11 represents a novel type of 17β-hydroxysteroid dehydrogenase with unique catalytic properties and tissue distribution. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Dengue Virus NS1 Protein Modulates Cellular Energy Metabolism by Increasing Glyceraldehyde-3-Phosphate Dehydrogenase Activity

    PubMed Central

    Allonso, Diego; Andrade, Iamara S.; Conde, Jonas N.; Coelho, Diego R.; Rocha, Daniele C. P.; da Silva, Manuela L.; Ventura, Gustavo T.

    2015-01-01

    ABSTRACT Dengue is one of the main public health concerns worldwide. Recent estimates indicate that over 390 million people are infected annually with the dengue virus (DENV), resulting in thousands of deaths. Among the DENV nonstructural proteins, the NS1 protein is the only one whose function during replication is still unknown. NS1 is a 46- to 55-kDa glycoprotein commonly found as both a membrane-associated homodimer and a soluble hexameric barrel-shaped lipoprotein. Despite its role in the pathogenic process, NS1 is essential for proper RNA accumulation and virus production. In the present study, we identified that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) interacts with intracellular NS1. Molecular docking revealed that this interaction occurs through the hydrophobic protrusion of NS1 and the hydrophobic residues located at the opposite side of the catalytic site. Moreover, addition of purified recombinant NS1 enhanced the glycolytic activity of GAPDH in vitro. Interestingly, we observed that DENV infection promoted the relocalization of GAPDH to the perinuclear region, where NS1 is commonly found. Both DENV infection and expression of NS1 itself resulted in increased GAPDH activity. Our findings indicate that the NS1 protein acts to increase glycolytic flux and, consequently, energy production, which is consistent with the recent finding that DENV induces and requires glycolysis for proper replication. This is the first report to propose that NS1 is an important modulator of cellular energy metabolism. The data presented here provide new insights that may be useful for further drug design and the development of alternative antiviral therapies against DENV. IMPORTANCE Dengue represents a serious public health problem worldwide and is caused by infection with dengue virus (DENV). Estimates indicate that half of the global population is at risk of infection, with almost 400 million cases occurring per year. The NS1 glycoprotein is found in both the

  2. Dengue Virus NS1 Protein Modulates Cellular Energy Metabolism by Increasing Glyceraldehyde-3-Phosphate Dehydrogenase Activity.

    PubMed

    Allonso, Diego; Andrade, Iamara S; Conde, Jonas N; Coelho, Diego R; Rocha, Daniele C P; da Silva, Manuela L; Ventura, Gustavo T; Silva, Emiliana M; Mohana-Borges, Ronaldo

    2015-12-01

    Dengue is one of the main public health concerns worldwide. Recent estimates indicate that over 390 million people are infected annually with the dengue virus (DENV), resulting in thousands of deaths. Among the DENV nonstructural proteins, the NS1 protein is the only one whose function during replication is still unknown. NS1 is a 46- to 55-kDa glycoprotein commonly found as both a membrane-associated homodimer and a soluble hexameric barrel-shaped lipoprotein. Despite its role in the pathogenic process, NS1 is essential for proper RNA accumulation and virus production. In the present study, we identified that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) interacts with intracellular NS1. Molecular docking revealed that this interaction occurs through the hydrophobic protrusion of NS1 and the hydrophobic residues located at the opposite side of the catalytic site. Moreover, addition of purified recombinant NS1 enhanced the glycolytic activity of GAPDH in vitro. Interestingly, we observed that DENV infection promoted the relocalization of GAPDH to the perinuclear region, where NS1 is commonly found. Both DENV infection and expression of NS1 itself resulted in increased GAPDH activity. Our findings indicate that the NS1 protein acts to increase glycolytic flux and, consequently, energy production, which is consistent with the recent finding that DENV induces and requires glycolysis for proper replication. This is the first report to propose that NS1 is an important modulator of cellular energy metabolism. The data presented here provide new insights that may be useful for further drug design and the development of alternative antiviral therapies against DENV. Dengue represents a serious public health problem worldwide and is caused by infection with dengue virus (DENV). Estimates indicate that half of the global population is at risk of infection, with almost 400 million cases occurring per year. The NS1 glycoprotein is found in both the intracellular and the

  3. Development of a headspace GC/MS analysis for carbonyl compounds (aldehydes and ketones) in household products after derivatization with o-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine.

    PubMed

    Sugaya, Naeko; Sakurai, Katsumi; Nakagawa, Tomoo; Onda, Nobuhiko; Onodera, Sukeo; Morita, Masatoshi; Tezuka, Masakatsu

    2004-05-01

    Carbonyl compounds (aldehydes and ketones) are suspected to be among the chemical compounds responsible for Sick Building Syndrome and Multiple Chemical Sensitivities. A headspace gas chromatography/mass spectrometry (GC/MS) analysis for these compounds was developed using derivatization of the compounds into volatile derivatives with o-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBOA). For GC/MS detection, two ionization modes including electron impact ionization (EI) and negative chemical ionization (NCI) were compared. The NCI mode seemed to be better because of its higher selectivity and sensitivity. This headspace GC/MS (NCI mode) was employed as analysis for aldehydes and ketones in materials (fiber products, adhesives, and printed materials). Formaldehyde was detected in the range of N.D. (not detected) to 39 microg/g; acetaldehyde, N.D. to 4.1 microg/g; propionaldehyde, N.D. to 1.0 microg/g; n-butyraldehyde, N.D. to 0.10 microg/g; and acetone, N.D. to 3.1 microg/g in the samples analyzed.

  4. Differences in expression of the cancer stem cell marker aldehyde dehydrogenase 1 among estrogen receptor-positive/human epidermal growth factor receptor type 2-negative breast cancer cases with early, late, and no recurrence.

    PubMed

    Miyoshi, Yuichiro; Shien, Tadahiko; Ogiya, Akiko; Ishida, Naoko; Yamazaki, Kieko; Horii, Rie; Horimoto, Yoshiya; Masuda, Norikazu; Yasojima, Hiroyuki; Inao, Touko; Osako, Tomofumi; Takahashi, Masato; Tomioka, Nobumoto; Endo, Yumi; Hosoda, Mitsuchika; Doihara, Hiroyoshi; Miyoshi, Shinichiro; Yamashita, Hiroko

    2016-07-02

    The significance of the expression of aldehyde dehydrogenase 1 (ALDH1), a cancer stem cell marker, for predicting the recurrence of estrogen receptor (ER)-positive/human epidermal growth factor receptor type 2 (HER2)-negative breast cancer is still poorly understood. The value of ALDH1 in predicting the time of recurrence remains unknown. In total, 184 patients with early distant recurrence, 134 patients with late distant recurrence, and 321 control patients without recurrence for more than 10 years after starting initial treatment for ER-positive/HER2-negative breast cancer, registered in 9 institutions, were analyzed. We assessed relationships between ALDH1 and other clinicopathological features, and ALDH1 expression was compared among the three groups. The relationship between ALDH1 expression and overall survival after recurrence was also evaluated in each group. The rates of ALDH1 expression positivity (more than 1 %) in the early, late, and no recurrence groups were 18.4 %, 13.4 %, and 8.4 %, respectively. ALDH1 expression correlated significantly with lymph node metastases (p = 0.048) and the Ki-67 labeling index (p < 0.001) in the early recurrence group. Multivariate analysis revealed ALDH1 expression to be significantly higher in the early recurrence group than in the no recurrence group (adjusted OR 2.140, 95 % CI 1.144-4.003, p = 0.016). Moreover, there was a significant difference in ALDH1 expression between the early and no recurrence groups receiving adjuvant endocrine therapy and chemotherapy (adjusted OR 4.625, 95 % CI 1.881-12.474, p < 0.001). However, there was no difference in ALDH1 expression between the late and no recurrence groups in univariate analysis (OR 1.507, 95 % CI 0.738-2.998, p = 0.253). In multivariate analysis, ALDH1 was not a factor independently predicting overall survival after the detection of recurrence (adjusted OR 1.451, 95 % CI 0.985-2.085, p = 0.059). Among patients with ER-positive/HER2

  5. Role of Microsomal Retinol/Sterol Dehydrogenase-Like Short-Chain Dehydrogenases/Reductases in the Oxidation and Epimerization of 3α-Hydroxysteroids in Human Tissues

    PubMed Central

    Belyaeva, Olga V.; Chetyrkin, Sergei V.; Clark, Amy L.; Kostereva, Natalia V.; SantaCruz, Karen S.; Chronwall, Bibie M.; Kedishvili, Natalia Y.

    2008-01-01

    Allopregnanolone (ALLO) and androsterone (ADT) are naturally occurring 3α-hydroxysteroids that act as positive allosteric regulators of γ-aminobutyric acid type A receptors. In addition, ADT activates nuclear farnesoid X receptor and ALLO activates pregnane X receptor. At least with respect to γ-aminobutyric acid type A receptors, the biological activity of ALLO and ADT depends on the 3α-hydroxyl group and is lost upon its conversion to either 3-ketosteroid or 3β-hydroxyl epimer. Such strict structure-activity relationships suggest that the oxidation or epimerization of 3α-hydroxysteroids may serve as physiologically relevant mechanisms for the control of the local concentrations of bioactive 3α-hydroxysteroids. The exact enzymes responsible for the oxidation and epimerization of 3α-hydroxysteroids in vivo have not yet been identified, but our previous studies showed that microsomal nicotinamide adenine dinucleotide-dependent short-chain dehydrogenases/reductases (SDRs) with dual retinol/sterol dehydrogenase substrate specificity (RoDH-like group of SDRs) can oxidize and epimerize 3α-hydroxysteroids in vitro. Here, we present the first evidence that microsomal nicotinamide adenine dinucleotide-dependent 3α-hydroxysteroid dehydrogenase/epimerase activities are widely distributed in human tissues with the highest activity levels found in liver and testis and lower levels in lung, spleen, brain, kidney, and ovary. We demonstrate that RoDH-like SDRs contribute to the oxidation and epimerization of ALLO and ADT in living cells, and show that RoDH enzymes are expressed in tissues that have microsomal 3α-hydroxysteroid dehydrogenase/epimerase activities. Together, these results provide further support for the role of RoDH-like SDRs in human metabolism of 3α-hydroxysteroids and offer a new insight into the enzymology of ALLO and ADT inactivation. PMID:17289849

  6. Role of microsomal retinol/sterol dehydrogenase-like short-chain dehydrogenases/reductases in the oxidation and epimerization of 3alpha-hydroxysteroids in human tissues.

    PubMed

    Belyaeva, Olga V; Chetyrkin, Sergei V; Clark, Amy L; Kostereva, Natalia V; SantaCruz, Karen S; Chronwall, Bibie M; Kedishvili, Natalia Y

    2007-05-01

    Allopregnanolone (ALLO) and androsterone (ADT) are naturally occurring 3alpha-hydroxysteroids that act as positive allosteric regulators of gamma-aminobutyric acid type A receptors. In addition, ADT activates nuclear farnesoid X receptor and ALLO activates pregnane X receptor. At least with respect to gamma-aminobutyric acid type A receptors, the biological activity of ALLO and ADT depends on the 3alpha-hydroxyl group and is lost upon its conversion to either 3-ketosteroid or 3beta-hydroxyl epimer. Such strict structure-activity relationships suggest that the oxidation or epimerization of 3alpha-hydroxysteroids may serve as physiologically relevant mechanisms for the control of the local concentrations of bioactive 3alpha-hydroxysteroids. The exact enzymes responsible for the oxidation and epimerization of 3alpha-hydroxysteroids in vivo have not yet been identified, but our previous studies showed that microsomal nicotinamide adenine dinucleotide-dependent short-chain dehydrogenases/reductases (SDRs) with dual retinol/sterol dehydrogenase substrate specificity (RoDH-like group of SDRs) can oxidize and epimerize 3alpha-hydroxysteroids in vitro. Here, we present the first evidence that microsomal nicotinamide adenine dinucleotide-dependent 3alpha-hydroxysteroid dehydrogenase/epimerase activities are widely distributed in human tissues with the highest activity levels found in liver and testis and lower levels in lung, spleen, brain, kidney, and ovary. We demonstrate that RoDH-like SDRs contribute to the oxidation and epimerization of ALLO and ADT in living cells, and show that RoDH enzymes are expressed in tissues that have microsomal 3alpha-hydroxysteroid dehydrogenase/epimerase activities. Together, these results provide further support for the role of RoDH-like SDRs in human metabolism of 3alpha-hydroxysteroids and offer a new insight into the enzymology of ALLO and ADT inactivation.

  7. Biochemical characterization of a recombinant short-chain NAD(H)-dependent dehydrogenase/reductase from Sulfolobus acidocaldarius.

    PubMed

    Pennacchio, Angela; Giordano, Assunta; Pucci, Biagio; Rossi, Mosè; Raia, Carlo A

    2010-03-01

    The gene encoding a novel alcohol dehydrogenase that belongs to the short-chain dehydrogenases/reductases (SDRs) superfamily was identified in the aerobic thermoacidophilic crenarchaeon Sulfolobus acidocaldarius strain DSM 639. The saadh gene was heterologously overexpressed in Escherichia coli, and the protein (SaADH) was purified to homogeneity and characterized. SaADH is a tetrameric enzyme consisting of identical 28,978-Da subunits, each composed of 264 amino acids. The enzyme has remarkable thermophilicity and thermal stability, displaying activity at temperatures up to 75 degrees C and a 30-min half-inactivation temperature of ~90 degrees C, and shows good tolerance to common organic solvents. SaADH has a strict requirement for NAD(H) as the coenzyme, and displays a preference for the reduction of alicyclic, bicyclic and aromatic ketones and alpha-keto esters, but is poorly active on aliphatic, cyclic and aromatic alcohols, and shows no activity on aldehydes. The enzyme catalyses the reduction of alpha-methyl and alpha-ethyl benzoylformate, and methyl o-chlorobenzoylformate with 100% conversion to methyl (S)-mandelate [17% enantiomeric excess (ee)], ethyl (R)-mandelate (50% ee), and methyl (R)-o-chloromandelate (72% ee), respectively, with an efficient in situ NADH-recycling system which involves glucose and a thermophilic glucose dehydrogenase. This study provides further evidence supporting the critical role of the D37 residue in discriminating NAD(H) from NAD(P)H in members of the SDR superfamily.

  8. Assignment of the human type I IMP dehydrogenase gene (IMPDH1) to chromosome 7q31.3-q32

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gu, Jing Jin; Kaiser-Rogers, K.; Rao, K.

    Two phage {lambda} clones that contain 5{prime} portion of the human type I inosine 5{prime}-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205) gene were isolated. Both polymerase chain reaction analysis of a panel of human-mouse and human-hamster cell somatic hybrids using primers specific for the type I IMPDH gene and fluorescence in situ hybridization with metaphase human chromosome using type I IMPDH genomic DNA as probes indicate that the type I IMPDH gene (symbol IMPDH1) is located on chromosome 7. Sequential GTG-banding was performed to assign the band location of the type I IMPDH gene to chromosome 7q31.3-q32. 16 refs., 1 fig., 1more » tab.« less

  9. New preparation of diethyl methylformylphosphonate dimethylhydrazone: A reagent for aldehyde homologation

    USDA-ARS?s Scientific Manuscript database

    The phosphonate reagent, diethyl methylformyl-2-phosphonate dimethylhydrazone contains a protected aldehyde group instead of the usual ester group. It can be used for the two-carbon homologation of aldehydes to a, ß-unsaturated aldehydes. The reagent can be prepared in good overall yield (82%) and...

  10. Polyvinyl alcohol cross-linked with two aldehydes

    NASA Technical Reports Server (NTRS)

    Sheibley, D. W.; Rieker, L. L.; Hsu, L. C.; Manzo, M. A. (Inventor)

    1982-01-01

    A film forming polyvinyl alcohol resin is admixed, in aqueous solution, with a dialdehyde crosslinking agent which is capable of crosslinking the polyvinyl alcohol resin and a water soluble acid aldehyde containing a reactive aldehyde group capable of reacting with hydroxyl groups in the polyvinyl alcohol resin and an ionizable acid hydrogen atom. The dialdehyde is present in an amount sufficient to react with from 1 to 20% by weight of the theoretical amount required to react with all of the hydroxyl groups of the polyvinyl alcohol. The amount of acid aldehyde is from 1 to 50% by weight, same basis, and is sufficient to reduce the pH of the aqueous admixture to 5 or less. The admixture is then formed into a desired physical shape, such as by casting a sheet or film, and the shaped material is then heated to simultaneously dry and crosslink the article.

  11. Mutations in human lipoyltransferase gene LIPT1 cause a Leigh disease with secondary deficiency for pyruvate and alpha-ketoglutarate dehydrogenase

    PubMed Central

    2013-01-01

    Background Synthesis and apoenzyme attachment of lipoic acid have emerged as a new complex metabolic pathway. Mutations in several genes involved in the lipoic acid de novo pathway have recently been described (i.e., LIAS, NFU1, BOLA3, IBA57), but no mutation was found so far in genes involved in the specific process of attachment of lipoic acid to apoenzymes pyruvate dehydrogenase (PDHc), α-ketoglutarate dehydrogenase (α-KGDHc) and branched chain α-keto acid dehydrogenase (BCKDHc) complexes. Methods Exome capture was performed in a boy who developed Leigh disease following a gastroenteritis and had combined PDH and α-KGDH deficiency with a unique amino acid profile that partly ressembled E3 subunit (dihydrolipoamide dehydrogenase / DLD) deficiency. Functional studies on patient fibroblasts were performed. Lipoic acid administration was tested on the LIPT1 ortholog lip3 deletion strain yeast and on patient fibroblasts. Results Exome sequencing identified two heterozygous mutations (c.875C > G and c.535A > G) in the LIPT1 gene that encodes a mitochondrial lipoyltransferase which is thought to catalyze the attachment of lipoic acid on PDHc, α-KGDHc, and BCKDHc. Anti-lipoic acid antibodies revealed absent expression of PDH E2, BCKDH E2 and α-KGDH E2 subunits. Accordingly, the production of 14CO2 by patient fibroblasts after incubation with 14Cglucose, 14Cbutyrate or 14C3OHbutyrate was very low compared to controls. cDNA transfection experiments on patient fibroblasts rescued PDH and α-KGDH activities and normalized the levels of pyruvate and 3OHbutyrate in cell supernatants. The yeast lip3 deletion strain showed improved growth on ethanol medium after lipoic acid supplementation and incubation of the patient fibroblasts with lipoic acid decreased lactate level in cell supernatants. Conclusion We report here a putative case of impaired free or H protein-derived lipoic acid attachment due to LIPT1 mutations as a cause of PDH and α-KGDH deficiencies. Our

  12. Mutations in human lipoyltransferase gene LIPT1 cause a Leigh disease with secondary deficiency for pyruvate and alpha-ketoglutarate dehydrogenase.

    PubMed

    Soreze, Yohan; Boutron, Audrey; Habarou, Florence; Barnerias, Christine; Nonnenmacher, Luc; Delpech, Hélène; Mamoune, Asmaa; Chrétien, Dominique; Hubert, Laurence; Bole-Feysot, Christine; Nitschke, Patrick; Correia, Isabelle; Sardet, Claude; Boddaert, Nathalie; Hamel, Yamina; Delahodde, Agnès; Ottolenghi, Chris; de Lonlay, Pascale

    2013-12-17

    Synthesis and apoenzyme attachment of lipoic acid have emerged as a new complex metabolic pathway. Mutations in several genes involved in the lipoic acid de novo pathway have recently been described (i.e., LIAS, NFU1, BOLA3, IBA57), but no mutation was found so far in genes involved in the specific process of attachment of lipoic acid to apoenzymes pyruvate dehydrogenase (PDHc), α-ketoglutarate dehydrogenase (α-KGDHc) and branched chain α-keto acid dehydrogenase (BCKDHc) complexes. Exome capture was performed in a boy who developed Leigh disease following a gastroenteritis and had combined PDH and α-KGDH deficiency with a unique amino acid profile that partly ressembled E3 subunit (dihydrolipoamide dehydrogenase / DLD) deficiency. Functional studies on patient fibroblasts were performed. Lipoic acid administration was tested on the LIPT1 ortholog lip3 deletion strain yeast and on patient fibroblasts. Exome sequencing identified two heterozygous mutations (c.875C > G and c.535A > G) in the LIPT1 gene that encodes a mitochondrial lipoyltransferase which is thought to catalyze the attachment of lipoic acid on PDHc, α-KGDHc, and BCKDHc. Anti-lipoic acid antibodies revealed absent expression of PDH E2, BCKDH E2 and α-KGDH E2 subunits. Accordingly, the production of 14CO2 by patient fibroblasts after incubation with 14Cglucose, 14Cbutyrate or 14C3OHbutyrate was very low compared to controls. cDNA transfection experiments on patient fibroblasts rescued PDH and α-KGDH activities and normalized the levels of pyruvate and 3OHbutyrate in cell supernatants. The yeast lip3 deletion strain showed improved growth on ethanol medium after lipoic acid supplementation and incubation of the patient fibroblasts with lipoic acid decreased lactate level in cell supernatants. We report here a putative case of impaired free or H protein-derived lipoic acid attachment due to LIPT1 mutations as a cause of PDH and α-KGDH deficiencies. Our study calls for renewed efforts to

  13. Identification of a new selective chemical inhibitor of mutant isocitrate dehydrogenase-1.

    PubMed

    Kim, Hyo-Joon; Choi, Bu Young; Keum, Young-Sam

    2015-03-01

    Recent genome-wide sequencing studies have identified unexpected genetic alterations in cancer. In particular, missense mutations in isocitrate dehydrogenase-1 (IDH1) at arginine 132, mostly substituted into histidine (IDH1-R132H) were observed to frequently occur in glioma patients. We have purified recombinant IDH1 and IDH1-R132H proteins and monitored their catalytic activities. In parallel experiments, we have attempted to find new selective IDH1-R132H chemical inhibitor(s) from a fragment-based chemical library. We have found that IDH1, but not IDH1-R132H, can catalyze the conversion of isocitrate into α-ketoglutarate (α-KG). In addition, we have observed that IDH1-R132H was more efficient than IDH1 in converting α-KG into (R)-2-hydroxyglutarate (R-2HG). Moreover, we have identified a new hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one as a new selective IDH1-R132H inhibitor. We have observed an underlying biochemical mechanism explaining how a heterozygous IDH1 mutation contributes to the generation of R-2HG and increases cellular histone H3 trimethylation levels. We have also identified a novel selective IDH1-R132H chemical hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one, which could be used for a future lead development against IDH1-R132H.

  14. Identification of a New Selective Chemical Inhibitor of Mutant Isocitrate Dehydrogenase-1

    PubMed Central

    Kim, Hyo-Joon; Choi, Bu Young; Keum, Young-Sam

    2015-01-01

    Background: Recent genome-wide sequencing studies have identified unexpected genetic alterations in cancer. In particular, missense mutations in isocitrate dehydrogenase-1 (IDH1) at arginine 132, mostly substituted into histidine (IDH1-R132H) were observed to frequently occur in glioma patients. Methods: We have purified recombinant IDH1 and IDH1-R132H proteins and monitored their catalytic activities. In parallel experiments, we have attempted to find new selective IDH1-R132H chemical inhibitor(s) from a fragment-based chemical library. Results: We have found that IDH1, but not IDH1-R132H, can catalyze the conversion of isocitrate into α-ketoglutarate (α-KG). In addition, we have observed that IDH1-R132H was more efficient than IDH1 in converting α-KG into (R)-2-hydroxyglutarate (R-2HG). Moreover, we have identified a new hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one as a new selective IDH1-R132H inhibitor. Conclusions: We have observed an underlying biochemical mechanism explaining how a heterozygous IDH1 mutation contributes to the generation of R-2HG and increases cellular histone H3 trimethylation levels. We have also identified a novel selective IDH1-R132H chemical hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one, which could be used for a future lead development against IDH1-R132H. PMID:25853107

  15. Discovery of BI 135585, an in vivo efficacious oxazinanone-based 11β hydroxysteroid dehydrogenase type 1 inhibitor.

    PubMed

    Zhuang, Linghang; Tice, Colin M; Xu, Zhenrong; Zhao, Wei; Cacatian, Salvacion; Ye, Yuan-Jie; Singh, Suresh B; Lindblom, Peter; McKeever, Brian M; Krosky, Paula M; Zhao, Yi; Lala, Deepak; Kruk, Barbara A; Meng, Shi; Howard, Lamont; Johnson, Judith A; Bukhtiyarov, Yuri; Panemangalore, Reshma; Guo, Joan; Guo, Rong; Himmelsbach, Frank; Hamilton, Bradford; Schuler-Metz, Annette; Schauerte, Heike; Gregg, Richard; McGeehan, Gerard M; Leftheris, Katerina; Claremon, David A

    2017-07-15

    A potent, in vivo efficacious 11β hydroxysteroid dehydrogenase type 1 (11β HSD1) inhibitor (11j) has been identified. Compound 11j inhibited 11β HSD1 activity in human adipocytes with an IC 50 of 4.3nM and in primary human adipose tissue with an IC 80 of 53nM. Oral administration of 11j to cynomolgus monkey inhibited 11β HSD1 activity in adipose tissue. Compound 11j exhibited >1000× selectivity over other hydroxysteroid dehydrogenases, displays desirable pharmacodynamic properties and entered human clinical trials in 2011. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Breast Cancer Resistance to Cyclophosphamide and Other Oxazaphosphorines

    DTIC Science & Technology

    1998-10-01

    Zr-75 and T-47D cells, colon carcinoma C cells, and salivary gland Warthin tumors and mucoepidermoid carcinomas), although otherwise seemingly...cytosolic class-3 aldehyde dehydrogenase by Warthin tumors and mucoepidermoid carcinomas of the parotid gland. Arch. Oral Biol., 41:597-605, 1996...specific cytosolic class-3 aldehyde dehydrogenase by Warthin tumours and mucoepidermoid carcinomas of the parotid gland. Archiv. Oral Biol., 41:597-605

  17. Chromatographic determination of aliphatic aldehydes in human serum after pre-column derivatization using 2,2'-furil, a novel fluorogenic reagent.

    PubMed

    Fathy Bakr Ali, Marwa; Kishikawa, Naoya; Ohyama, Kaname; Abdel-Mageed Mohamed, Horria; Mohamed Abdel-Wadood, Hanaa; Mohamed Mohamed, Ashraf; Kuroda, Naotaka

    2013-07-26

    A novel, highly sensitive and selective fluorimetric liquid chromatographic method for simultaneous determination of medium chain aliphatic aldehydes was developed. The method was based on the derivatization of aliphatic aldehydes with 1,2-di(2-furyl)-1,2-ethanedione (2,2'-furil), a novel fluorogenic reagent, to form highly fluorescent difurylimidazole derivatives. The fluorescence derivatives were separated in less than 20min on a reversed-phase ODS column using an isocratic elution with a mixture of methanol-water (80:20, v/v%). The detection limits were from 0.19 to 0.50nM (1-10fmol/injection) at a signal-to-noise ratio (S/N) of 3. This method was successfully applied for monitoring of aliphatic aldehydes in healthy human sera by a simple pretreatment procedure without interferences from serum constituents. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Crystallization and preliminary X-ray study of a (2R,3R)-2,3-butanediol dehydrogenase from Bacillus coagulans 2-6

    PubMed Central

    Miao, Xiangzhi; Huang, Xianhui; Zhang, Guofang; Zhao, Xiufang; Zhu, Xianming; Dong, Hui

    2013-01-01

    (2R,3R)-2,3-Butanediol dehydrogenase (R,R-BDH) from Bacillus coagulans 2-6 is a zinc-dependent medium-chain alcohol dehydrogenase. Recombinant R,R-BDH with a His6 tag at the C-terminus was expressed in Escherichia coli BL21 (DE3) cells and purified by Ni2+-chelating affinity and size-exclusion chromatography. Crystals were grown by the hanging-drop vapour-diffusion method at 289 K. The crystallization condition consisted of 8%(v/v) Tacsimate pH 4.6, 18%(w/v) polyethylene glycol 3350. The crystal diffracted to 2.8 Å resolution in the orthorhombic space group P212121, with unit-cell parameters a = 88.35, b = 128.73, c = 131.03 Å. PMID:24100567

  19. Crystallization and preliminary X-ray study of a (2R,3R)-2,3-butanediol dehydrogenase from Bacillus coagulans 2-6.

    PubMed

    Miao, Xiangzhi; Huang, Xianhui; Zhang, Guofang; Zhao, Xiufang; Zhu, Xianming; Dong, Hui

    2013-10-01

    (2R,3R)-2,3-Butanediol dehydrogenase (R,R-BDH) from Bacillus coagulans 2-6 is a zinc-dependent medium-chain alcohol dehydrogenase. Recombinant R,R-BDH with a His6 tag at the C-terminus was expressed in Escherichia coli BL21 (DE3) cells and purified by Ni2+-chelating affinity and size-exclusion chromatography. Crystals were grown by the hanging-drop vapour-diffusion method at 289 K. The crystallization condition consisted of 8%(v/v) Tacsimate pH 4.6, 18%(w/v) polyethylene glycol 3350. The crystal diffracted to 2.8 Å resolution in the orthorhombic space group P2₁2₁2₁, with unit-cell parameters a=88.35, b=128.73, c=131.03 Å.

  20. Effect of Aldehyde Dehydrogenase 2 Gene Polymorphism on Hemodynamics After Nitroglycerin Intervention in Northern Chinese Han Population

    PubMed Central

    Xia, Jia-Qi; Song, Jie; Zhang, Yi; An, Ni-Na; Ding, Lei; Zhang, Zheng

    2015-01-01

    Background: Nitroglycerin (NTG) is one of the few immediate treatments for acute angina. Aldehyde dehydrogenase 2 (ALDH2) is a key enzyme in the human body that facilitates the biological metabolism of NTG. The biological mechanism of NTG serves an important function in NTG efficacy. Some reports still contradict the results that the correlation between ALDH2 gene polymorphisms and NTG and its clinical efficacy is different. However, data on NTG measurement by pain relief are subjective. This study aimed to investigate the influence of ALDH2 gene polymorphism on intervention with sublingual NTG using noninvasive hemodynamic parameters of cardiac output (CO) and systemic vascular resistance (SVR) in Northern Chinese Han population. Methods: This study selected 559 patients from the Affiliated Hospital of Qingdao University. A total of 203 patients presented with coronary heart disease (CHD) and 356 had non-CHD (NCHD) cases. All patient ALDH2 genotypes (G504A) were detected and divided into two types: Wild (GG) and mutant (GA/AA). Among the CHD group, 103 were wild-type cases, and 100 were mutant-type cases. Moreover, 196 cases were wild-type, and 160 cases were mutant type among the NCHD volunteers. A noninvasive hemodynamic detector was used to monitor the CO and the SVR at the 0, 5, and 15 minute time points after medication with 0.5 mg sublingual NTG. Two CO and SVR indicators were used for a comparative analysis of all case genotypes. Results: Both CO and SVR indicators significantly differed between the wild and mutant genotypes at various time points after intervention with sublingual NTG at 5 and 15 minutes in the NCHD (F = 16.460, 15.003, P = 0.000, 0.000) and CHD groups (F = 194.482, 60.582, P = 0.000, 0.000). All CO values in the wild-type case of both NCHD and CHD groups increased, whereas those in the mutant type decreased. The CO and ΔCO differences were statistically significant (P < 0.05; P < 0.05). The SVR and ΔSVR changed between the wild- and

  1. Alcohol, Aldehydes, Adducts and Airways

    PubMed Central

    Sapkota, Muna; Wyatt, Todd A.

    2015-01-01

    Drinking alcohol and smoking cigarettes results in the formation of reactive aldehydes in the lung, which are capable of forming adducts with several proteins and DNA. Acetaldehyde and malondialdehyde are the major aldehydes generated in high levels in the lung of subjects with alcohol use disorder who smoke cigarettes. In addition to the above aldehydes, several other aldehydes like 4-hydroxynonenal, formaldehyde and acrolein are also detected in the lung due to exposure to toxic gases, vapors and chemicals. These aldehydes react with nucleophilic targets in cells such as DNA, lipids and proteins to form both stable and unstable adducts. This adduction may disturb cellular functions as well as damage proteins, nucleic acids and lipids. Among several adducts formed in the lung, malondialdehyde DNA (MDA-DNA) adduct and hybrid malondialdehyde-acetaldehyde (MAA) protein adducts have been shown to initiate several pathological conditions in the lung. MDA-DNA adducts are pre-mutagenic in mammalian cells and induce frame shift and base-pair substitution mutations, whereas MAA protein adducts have been shown to induce inflammation and inhibit wound healing. This review provides an insight into different reactive aldehyde adducts and their role in the pathogenesis of lung disease. PMID:26556381

  2. Alcohol, Aldehydes, Adducts and Airways.

    PubMed

    Sapkota, Muna; Wyatt, Todd A

    2015-11-05

    Drinking alcohol and smoking cigarettes results in the formation of reactive aldehydes in the lung, which are capable of forming adducts with several proteins and DNA. Acetaldehyde and malondialdehyde are the major aldehydes generated in high levels in the lung of subjects with alcohol use disorder who smoke cigarettes. In addition to the above aldehydes, several other aldehydes like 4-hydroxynonenal, formaldehyde and acrolein are also detected in the lung due to exposure to toxic gases, vapors and chemicals. These aldehydes react with nucleophilic targets in cells such as DNA, lipids and proteins to form both stable and unstable adducts. This adduction may disturb cellular functions as well as damage proteins, nucleic acids and lipids. Among several adducts formed in the lung, malondialdehyde DNA (MDA-DNA) adduct and hybrid malondialdehyde-acetaldehyde (MAA) protein adducts have been shown to initiate several pathological conditions in the lung. MDA-DNA adducts are pre-mutagenic in mammalian cells and induce frame shift and base-pair substitution mutations, whereas MAA protein adducts have been shown to induce inflammation and inhibit wound healing. This review provides an insight into different reactive aldehyde adducts and their role in the pathogenesis of lung disease.

  3. Flavoring Chemicals and Aldehydes in E-Cigarette Emissions.

    PubMed

    Klager, Skylar; Vallarino, Jose; MacNaughton, Piers; Christiani, David C; Lu, Quan; Allen, Joseph G

    2017-09-19

    Regulations on e-cigarettes in the U.S. do not provide guidelines on the chemical content of e-cigarette liquids. We evaluated emissions of aldehydes and flavoring chemicals in e-cigarette vapor under typical usage conditions. We selected 24 e-cigarette flavors from the top selling disposable e-cigarette brands. E-cigarettes were connected to a pump drawing air for two second puffs with sixty-second intervals between puffs. The vapor was analyzed for the presence of aldehydes using high-performance liquid chromatography-ultraviolet detector and for the presence of flavoring chemicals with gas chromatography and an electron capture detector. All e-cigarette emissions tested contained at least one aldehyde and/or flavoring chemical on either the FEMA "High Priority Chemicals" or FDA Harmful and Potentially Harmful Constituents lists when sampled at typical usage conditions. Diacetyl, a known respiratory hazard, along with acetoin, were the most prevalent of the flavoring chemicals in e-cigarette vapor, being found in more than 60% of samples. The presence of propionaldehyde, acetaldehyde and formaldehyde were correlated, corroborating previous work suggesting thermal degradation as a pathway for aldehyde generation in e-cigarette vapors. Median formaldehyde concentrations of 626 μg/m 3 in e-cigarette vapor exceed the ACGIH maximum concentrations allowable for workers of 370 μg/m 3 .

  4. The E1 beta-subunit of pyruvate dehydrogenase is surface-expressed in Lactobacillus plantarum and binds fibronectin.

    PubMed

    Vastano, Valeria; Salzillo, Marzia; Siciliano, Rosa A; Muscariello, Lidia; Sacco, Margherita; Marasco, Rosangela

    2014-01-01

    Lactobacillus plantarum is among the species with a probiotic activity. Adhesion of probiotic bacteria to host tissues is an important principle for strain selection, because it represents a crucial step in the colonization process of either pathogens or commensals. Most bacterial adhesins are proteins, and a major target for them is fibronectin, an extracellular matrix glycoprotein. In this study we demonstrate that PDHB, a component of the pyruvate dehydrogenase complex, is a factor contributing to fibronectin-binding in L. plantarum LM3. By means of fibronectin overlay immunoblotting assay, we identified a L. plantarum LM3 surface protein with apparent molecular mass of 35 kDa. Mass spectrometric analysis shows that this protein is the pyruvate dehydrogenase E1 beta-subunit (PDHB). The corresponding pdhB gene is located in a 4-gene cluster encoding pyruvate dehydrogenase. In LM3-B1, carrying a null mutation in pdhB, the 35 kDa adhesin was not anymore detectable by immunoblotting assay. Nevertheless, the pdhB null mutation did not abolish pdhA, pdhC, and pdhD transcription in LM3-B1. By adhesion assays, we show that LM3-B1 cells bind to immobilized fibronectin less efficiently than wild type cells. Moreover, we show that pdhB expression is negatively regulated by the CcpA protein and is induced by bile. Copyright © 2013. Published by Elsevier GmbH.

  5. Myoglobin-Catalyzed Olefination of Aldehydes.

    PubMed

    Tyagi, Vikas; Fasan, Rudi

    2016-02-12

    The olefination of aldehydes constitutes a most valuable and widely adopted strategy for constructing carbon-carbon double bonds in organic chemistry. While various synthetic methods have been made available for this purpose, no biocatalysts are known to mediate this transformation. Reported herein is that engineered myoglobin variants can catalyze the olefination of aldehydes in the presence of α-diazoesters with high catalytic efficiency (up to 4,900 turnovers) and excellent E diastereoselectivity (92-99.9 % de). This transformation could be applied to the olefination of a variety of substituted benzaldehydes and heteroaromatic aldehydes, also in combination with different alkyl α-diazoacetate reagents. This work provides a first example of biocatalytic aldehyde olefination and extends the spectrum of synthetically valuable chemical transformations accessible using metalloprotein-based catalysts. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Changes in cinnamyl alcohol dehydrogenase activities from sugarcane cultivars inoculated with Sporisorium scitamineum sporidia.

    PubMed

    Santiago, Rocío; Alarcón, Borja; de Armas, Roberto; Vicente, Carlos; Legaz, María Estrella

    2012-06-01

    This study describes a method for determining cinnamyl alcohol dehydrogenase activity in sugarcane stems using reverse phase (RP) high-performance liquid chromatography to elucidate their possible lignin origin. Activity is assayed using the reverse mode, the oxidation of hydroxycinnamyl alcohols into hydroxycinnamyl aldehydes. Appearance of the reaction products, coniferaldehyde and sinapaldehyde is determined by measuring absorbance at 340 and 345 nm, respectively. Disappearance of substrates, coniferyl alcohol and sinapyl alcohol is measured at 263 and 273 nm, respectively. Isocratic elution with acetonitrile:acetic acid through an RP Mediterranea sea C18 column is performed. As case examples, we have examined two different cultivars of sugarcane; My 5514 is resistant to smut, whereas B 42231 is susceptible to the pathogen. Inoculation of sugarcane stems elicits lignification and produces significant increases of coniferyl alcohol dehydrogenase (CAD) and sinapyl alcohol dehydrogenase (SAD). Production of lignin increases about 29% in the resistant cultivar and only 13% in the susceptible cultivar after inoculation compared to uninoculated plants. Our results show that the resistance of My 5514 to smut is likely derived, at least in part, to a marked increase of lignin concentration by the activation of CAD and SAD. Copyright © Physiologia Plantarum 2012.

  7. The Alcohol Dehydrogenase Isoenzyme as a Potential Marker of Pancreatitis.

    PubMed

    Jelski, Wojciech; Piechota, Joanna; Orywal, Karolina; Szmitkowski, Maciej

    2018-05-01

    Human pancreas parenchyma contains various alcohol dehydrogenase (ADH) isoenzymes and also possesses aldehyde dehydrogenase (ALDH) activity. The altered activities of ADH and ALDH in damaged pancreatic tissue in the course of pancreatitis are reflected in the human serum. The aim of this study was to investigate a potential role of ADH and ALDH as markers for acute (AP) and chronic pancreatitis (CP). Serum samples were collected for routine biochemical investigations from 75 patients suffering from acute pancreatitis and 70 patients with chronic pancreatitis. Fluorometric methods were used to measure the activity of class I and II ADH and ALDH activity. The total ADH activity and activity of class III and IV isoenzymes were measured by a photometric method. There was a significant increase in the activity of ADH III isoenzyme (15.06 mU/l and 14.62 mU/l vs. 11.82 mU/l; p<0.001) and total ADH activity (764 mU/l and 735 mU/l vs. 568 mU/l) in the sera of patients with acute pancreatitis or chronic pancreatitis compared to the control. The diagnostic sensitivity for ADH III was about 84%, specificity was 92 %, positive and negative predictive values were 93% and 87% respectively in acute pancreatitis. Area under the Receiver Operating Curve (ROC) curve for ADH III in AP and CP was 0.88 and 0.86 respectively. ADH III has a potential role as a marker of acute and chronic pancreatitis. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  8. Cyclohexanecarboxyl-Coenzyme A (CoA) and Cyclohex-1-ene-1-Carboxyl-CoA Dehydrogenases, Two Enzymes Involved in the Fermentation of Benzoate and Crotonate in Syntrophus aciditrophicus

    PubMed Central

    Kung, Johannes W.; Seifert, Jana; von Bergen, Martin

    2013-01-01

    The strictly anaerobic Syntrophus aciditrophicus is a fermenting deltaproteobacterium that is able to degrade benzoate or crotonate in the presence and in the absence of a hydrogen-consuming partner. During growth in pure culture, both substrates are dismutated to acetate and cyclohexane carboxylate. In this work, the unknown enzymes involved in the late steps of cyclohexane carboxylate formation were studied. Using enzyme assays monitoring the oxidative direction, a cyclohex-1-ene-1-carboxyl-CoA (Ch1CoA)-forming cyclohexanecarboxyl-CoA (ChCoA) dehydrogenase was purified and characterized from S. aciditrophicus and after heterologous expression of its gene in Escherichia coli. In addition, a cyclohexa-1,5-diene-1-carboxyl-CoA (Ch1,5CoA)-forming Ch1CoA dehydrogenase was characterized after purification of the heterologously expressed gene. Both enzymes had a native molecular mass of 150 kDa and were composed of a single, 40- to 45-kDa subunit; both contained flavin adenine dinucleotide (FAD) as a cofactor. While the ChCoA dehydrogenase was competitively inhibited by Ch1CoA in the oxidative direction, Ch1CoA dehydrogenase further converted the product Ch1,5CoA to benzoyl-CoA. The results obtained suggest that Ch1,5CoA is a common intermediate in benzoate and crotonate fermentation that serves as an electron-accepting substrate for the two consecutively operating acyl-CoA dehydrogenases characterized in this work. In the case of benzoate fermentation, Ch1,5CoA is formed by a class II benzoyl-CoA reductase; in the case of crotonate fermentation, Ch1,5CoA is formed by reversing the reactions of the benzoyl-CoA degradation pathway that are also employed during the oxidative (degradative) branch of benzoate fermentation. PMID:23667239

  9. Direct Electrochemical Addressing of Immobilized Alcohol Dehydrogenase for the Heterogeneous Bioelectrocatalytic Reduction of Butyraldehyde to Butanol.

    PubMed

    Schlager, S; Neugebauer, H; Haberbauer, M; Hinterberger, G; Sariciftci, N S

    2015-03-01

    Modified electrodes using immobilized alcohol dehydrogenase enzymes for the efficient electroreduction of butyraldehyde to butanol are presented as an important step for the utilization of CO 2 -reduction products. Alcohol dehydrogenase was immobilized, embedded in an alginate-silicate hybrid gel, on a carbon felt (CF) electrode. The application of this enzyme to the reduction of an aldehyde to an alcohol with the aid of the coenzyme nicotinamide adenine dinucleotide (NADH), in analogy to the final step in the natural reduction cascade of CO 2 to alcohol, has been already reported. However, the use of such enzymatic reductions is limited because of the necessity of providing expensive NADH as a sacrificial electron and proton donor. Immobilization of such dehydrogenase enzymes on electrodes and direct pumping of electrons into the biocatalysts offers an easy and efficient way for the biochemical recycling of CO 2 to valuable chemicals or alternative synthetic fuels. We report the direct electrochemical addressing of immobilized alcohol dehydrogenase for the reduction of butyraldehyde to butanol without consumption of NADH. The selective reduction of butyraldehyde to butanol occurs at room temperature, ambient pressure and neutral pH. Production of butanol was detected by using liquid-injection gas chromatography and was estimated to occur with Faradaic efficiencies of around 40 %.

  10. Deodorants: an experimental provocation study with cinnamic aldehyde.

    PubMed

    Bruze, Magnus; Johansen, J D; Andersen, K E; Frosch, P; Lepoittevin, J-P; Rastogi, S; Wakelin, S; White, I; Menné, T

    2003-02-01

    Axillary dermatitis is common and overrepresented in individuals with contact allergy to fragrances. Many individuals suspect their deodorants to be the incriminating products. Our aim was to investigate the significance of cinnamic aldehyde in deodorants for the development of axillary dermatitis when used by individuals with and without contact allergy to cinnamic aldehyde. Patch tests with deodorants and ethanol solutions with cinnamic aldehyde, and repeated open application tests with roll-on deodorants without and with cinnamic aldehyde at different concentrations, were performed in 37 patients with dermatitis, 20 without and 17 with contact allergy to cinnamic aldehyde. A repeated open application test with positive findings was noted only in patients hypersensitive to cinnamic aldehyde (P <.001) and only in the axilla to which the deodorants containing cinnamic aldehyde had been applied (P <.001). Deodorants containing cinnamic aldehyde in the concentration range 0.01% to 0.32%, used twice daily on healthy skin, can elicit axillary dermatitis within a few weeks.

  11. Aldehydes with high and low toxicities inactivate cells by damaging distinct cellular targets.

    PubMed

    Xie, Ming-Zhang; Shoulkamy, Mahmoud I; Salem, Amir M H; Oba, Shunya; Goda, Mizuki; Nakano, Toshiaki; Ide, Hiroshi

    2016-04-01

    Aldehydes are genotoxic and cytotoxic molecules and have received considerable attention for their associations with the pathogenesis of various human diseases. In addition, exposure to anthropogenic aldehydes increases human health risks. The general mechanism of aldehyde toxicity involves adduct formation with biomolecules such as DNA and proteins. Although the genotoxic effects of aldehydes such as mutations and chromosomal aberrations are directly related to DNA damage, the role of DNA damage in the cytotoxic effects of aldehydes is poorly understood because concurrent protein damage by aldehydes has similar effects. In this study, we have analysed how saturated and α,β-unsaturated aldehydes exert cytotoxic effects through DNA and protein damage. Interestingly, DNA repair is essential for alleviating the cytotoxic effect of weakly toxic aldehydes such as saturated aldehydes but not highly toxic aldehydes such as long α,β-unsaturated aldehydes. Thus, highly toxic aldehydes inactivate cells exclusively by protein damage. Our data suggest that DNA interstrand crosslinks, but not DNA-protein crosslinks and DNA double-strand breaks, are the critical cytotoxic DNA damage induced by aldehydes. Further, we show that the depletion of intracellular glutathione and the oxidation of thioredoxin 1 partially account for the DNA damage-independent cytotoxicity of aldehydes. On the basis of these findings, we have proposed a mechanistic model of aldehyde cytotoxicity mediated by DNA and protein damage. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Brown Carbon Production in Aldehyde + Ammonium Sulfate Mixtures: Effects of Formaldehyde and Amines

    NASA Astrophysics Data System (ADS)

    Powelson, M.; De Haan, D. O.

    2012-12-01

    The formation of light-absorbing 'brown carbon,' or HULIS (humic- like substances), in atmospheric aerosol has an important impact on climate. However, the precursors responsible for brown carbon formation have not been identified. Several aldehydes present in clouds (methylglyoxal, glycolaldehyde, hydroxyacetone, glyoxal, and acetaldehyde) have the potential to create brown products when reacted with ammonium sulfate or primary amines such as methylamine or glycine. The formation of light-absorbing products from these reactions was characterized as a function of cloud-relevant pH (from 3- 6) using UV-Visible spectroscopy. Of the different aldehydes teste, the largest production rates of light-absorbing compounds were observed in reactions of glycolaldehyde and methylglyoxal. Primary amines produced more light- absorbing products than ammonium sulfate at lower concentrations. The addition of formaldehyde to any reaction with other aldehydes decreased the formation of light-absorbing products, while the addition of a small amount (1:5 mole ratio) of glycine to aldehyde + ammonium sulfate reactions can increase the production of light-absorbing products. These results suggest that the presence of primary amines significantly influence atmospheric brown carbon production by aldehydes even when much greater quantities of ammonium sulfate are present.

  13. From Waste to Plastic: Synthesis of Poly(3-Hydroxypropionate) in Shimwellia blattae

    PubMed Central

    Heinrich, Daniel; Andreessen, Björn; Madkour, Mohamed H.; Al-Ghamdi, Mansour A.; Shabbaj, Ibrahim I.

    2013-01-01

    In recent years, glycerol has become an attractive carbon source for microbial processes, as it accumulates massively as a by-product of biodiesel production, also resulting in a decline of its price. A potential use of glycerol in biotechnology is the synthesis of poly(3-hydroxypropionate) [poly(3HP)], a biopolymer with promising properties which is not synthesized by any known wild-type organism. In this study, the genes for 1,3-propanediol dehydrogenase (dhaT) and aldehyde dehydrogenase (aldD) of Pseudomonas putida KT2442, propionate-coenzyme A (propionate-CoA) transferase (pct) of Clostridium propionicum X2, and polyhydroxyalkanoate (PHA) synthase (phaC1) of Ralstonia eutropha H16 were cloned and expressed in the 1,3-propanediol producer Shimwellia blattae. In a two-step cultivation process, recombinant S. blattae cells accumulated up to 9.8% ± 0.4% (wt/wt [cell dry weight]) poly(3HP) with glycerol as the sole carbon source. Furthermore, the engineered strain tolerated the application of crude glycerol derived from biodiesel production, yielding a cell density of 4.05 g cell dry weight/liter in a 2-liter fed-batch fermentation process. PMID:23542629

  14. From waste to plastic: synthesis of poly(3-hydroxypropionate) in Shimwellia blattae.

    PubMed

    Heinrich, Daniel; Andreessen, Björn; Madkour, Mohamed H; Al-Ghamdi, Mansour A; Shabbaj, Ibrahim I; Steinbüchel, Alexander

    2013-06-01

    In recent years, glycerol has become an attractive carbon source for microbial processes, as it accumulates massively as a by-product of biodiesel production, also resulting in a decline of its price. A potential use of glycerol in biotechnology is the synthesis of poly(3-hydroxypropionate) [poly(3HP)], a biopolymer with promising properties which is not synthesized by any known wild-type organism. In this study, the genes for 1,3-propanediol dehydrogenase (dhaT) and aldehyde dehydrogenase (aldD) of Pseudomonas putida KT2442, propionate-coenzyme A (propionate-CoA) transferase (pct) of Clostridium propionicum X2, and polyhydroxyalkanoate (PHA) synthase (phaC1) of Ralstonia eutropha H16 were cloned and expressed in the 1,3-propanediol producer Shimwellia blattae. In a two-step cultivation process, recombinant S. blattae cells accumulated up to 9.8% ± 0.4% (wt/wt [cell dry weight]) poly(3HP) with glycerol as the sole carbon source. Furthermore, the engineered strain tolerated the application of crude glycerol derived from biodiesel production, yielding a cell density of 4.05 g cell dry weight/liter in a 2-liter fed-batch fermentation process.

  15. Citral reduces breast tumor growth by inhibiting the cancer stem cell marker ALDH1A3.

    PubMed

    Thomas, Margaret Lois; de Antueno, Roberto; Coyle, Krysta Mila; Sultan, Mohammad; Cruickshank, Brianne Marie; Giacomantonio, Michael Anthony; Giacomantonio, Carman Anthony; Duncan, Roy; Marcato, Paola

    2016-11-01

    Breast cancer stem cells (CSCs) can be identified by increased Aldefluor fluorescence caused by increased expression of aldehyde dehydrogenase 1A3 (ALDH1A3), as well as ALDH1A1 and ALDH2. In addition to being a CSC marker, ALDH1A3 regulates gene expression via retinoic acid (RA) signaling and plays a key role in the progression and chemotherapy resistance of cancer. Therefore, ALDH1A3 represents a druggable anti-cancer target of interest. Since to date, there are no characterized ALDH1A3 isoform inhibitors, drugs that were previously described as inhibiting the activity of other ALDH isoforms were tested for anti-ALDH1A3 activity. Twelve drugs (3-hydroxy-dl-kynurenine, benomyl, citral, chloral hydrate, cyanamide, daidzin, DEAB, disulfiram, gossypol, kynurenic acid, molinate, and pargyline) were compared for their efficacy in inducing apoptosis and reducing ALDH1A3, ALDH1A1 and ALDH2-associated Aldefluor fluorescence in breast cancer cells. Citral was identified as the best inhibitor of ALDH1A3, reducing the Aldefluor fluorescence in breast cancer cell lines and in a patient-derived tumor xenograft. Nanoparticle encapsulated citral specifically reduced the enhanced tumor growth of MDA-MB-231 cells overexpressing ALDH1A3. To determine the potential mechanisms of citral-mediated tumor growth inhibition, we performed cell proliferation, clonogenic, and gene expression assays. Citral reduced ALDH1A3-mediated colony formation and expression of ALDH1A3-inducible genes. In conclusion, citral is an effective ALDH1A3 inhibitor and is able to block ALDH1A3-mediated breast tumor growth, potentially via blocking its colony forming and gene expression regulation activity. The promise of ALDH1A3 inhibitors as adjuvant therapies for patients with tumors that have a large population of high-ALDH1A3 CSCs is discussed. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  16. Expression, purification, crystallization and preliminary X-ray analysis of an NAD-dependent glyceraldehyde-3-phosphate dehydrogenase from Helicobacter pylori

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elliott, Paul R.; Mohammad, Shabaz; Melrose, Helen J.

    2008-08-01

    Glyceraldehyde-3-phosphate dehydrogenase B from H. pylori has been cloned, expressed, purified and crystallized in the presence of NAD. Crystals of GAPDHB diffracted to 2.8 Å resolution and belonged to space group P6{sub 5}22, with unit-cell parameters a = b = 166.1, c = 253.1 Å. Helicobacter pylori is a dangerous human pathogen that resides in the upper gastrointestinal tract. Little is known about its metabolism and with the onset of antibiotic resistance new treatments are required. In this study, the expression, purification, crystallization and preliminary X-ray diffraction of an NAD-dependent glyceraldehyde-3-phosphate dehydrogenase from H. pylori are reported.

  17. Malate dehydrogenase of the cytosol. A kinetic investigation of the reaction mechanism and a comparison with lactate dehydrogenase.

    PubMed Central

    Lodola, A; Shore, J D; Parker, D M; Holbrook, J

    1978-01-01

    1. The mechanisms of the reduction of oxaloacetate and of 3-fluoro-oxaloacetate by NADH catalysed by cytoplasmic pig heart malate dehydrogenase (MDH) were investigated. 2. One mol of dimeric enzyme produces 1.7+/-0.4 mol of enzyme-bound NADH when mixed with saturating NAD+ and L-malate at a rate much higher than the subsequent turnover at pH 7.5. 3. Transient measurements of protein and nucleotide fluorescence show that the steady-state complex in the forward direction is MDH-NADH and in the reverse direction MDH-NADH-oxaloacetate. 4. The rate of dissociation of MDH-NADH was measured and is the same as Vmax. in the forward direction at pH 7.5. Both NADH-binding sites are kinetically equivalent. The rate of dissociation varies with pH, as does the equilibrium binding constant for NADH. 5. 3-Fluoro-oxaloacetate is composed of three forms (F1, F2 and S) of which F1 and F2 are immediately substrates for the enzyme. The third form, S, is not a substrate, but when the F forms are used up form S slowly and non-enzymically equilibrates to yield the active substrate forms. S is 2,2-dihydroxy-3-fluorosuccinate. 6. The steady-state compound during the reduction of form F1 is an enzyme form that does not contain NADH, probably MDH-NAD+-fluoromalate. The steady-state compound for form F2 is an enzyme form containing NADH, probably MDH-NADH-fluoro-oxaloacetate. 7. The rate-limiting reaction in the reduction of form F2 shows a deuterium isotope rate ratio of 4 when NADH is replaced by its deuterium analogue, and the rate-limiting reaction is concluded to be hydride transfer. 8. A novel titration was used to show that dimeric cytoplasmic malate dehydrogenase contains two sites that can rapidly reduce the F1 form of 3-fluoro-oxaloacetate. The enzyme shows 'all-of-the-sites' behaviour. 9. Partial mechanisms are proposed to explain the enzyme-catalysed transformations of the natural and the fluoro substrates. These mechanisms are similar to the mechanism of pig heart lactate

  18. The effect of peroxynitrite decomposition catalyst MnTBAP on aldehyde dehydrogenase-2 nitration by organic nitrates: role in nitrate tolerance.

    PubMed

    Mollace, Vincenzo; Muscoli, Carolina; Dagostino, Concetta; Giancotti, Luigino Antonio; Gliozzi, Micaela; Sacco, Iolanda; Visalli, Valeria; Gratteri, Santo; Palma, Ernesto; Malara, Natalia; Musolino, Vincenzo; Carresi, Cristina; Muscoli, Saverio; Vitale, Cristiana; Salvemini, Daniela; Romeo, Francesco

    2014-11-01

    Bioconversion of glyceryl trinitrate (GTN) into nitric oxide (NO) by aldehyde dehydrogenase-2 (ALDH-2) is a crucial mechanism which drives vasodilatory and antiplatelet effect of organic nitrates in vitro and in vivo. Oxidative stress generated by overproduction of free radical species, mostly superoxide anions and NO-derived peroxynitrite, has been suggested to play a pivotal role in the development of nitrate tolerance, though the mechanism still remains unclear. Here we studied the free radical-dependent impairment of ALDH-2 in platelets as well as vascular tissues undergoing organic nitrate ester tolerance and potential benefit when using the selective peroxynitrite decomposition catalyst Mn(III) tetrakis (4-Benzoic acid) porphyrin (MnTBAP). Washed human platelets were made tolerant to nitrates via incubation with GTN for 4h. This was expressed by attenuation of platelet aggregation induced by thrombin (40U/mL), an effect accompanied by GTN-related induction of cGMP levels in platelets undergoing thrombin-induced aggregation. Both effects were associated to attenuated GTN-induced nitrite formation in platelets supernatants and to prominent nitration of ALDH-2, the GTN to NO metabolizing enzyme, suggesting that GTN tolerance was associated to reduced NO formation via impairment of ALDH-2. These effects were all antagonized by co-incubation of platelets with MnTBAP, which restored GTN-induced responses in tolerant platelets. Comparable effect was found under in in vivo settings. Indeed, MnTBAP (10mg/kg, i.p.) significantly restored the hypotensive effect of bolus injection of GTN in rats made tolerants to organic nitrates via chronic administration of isosorbide-5-mononitrate (IS-5-MN), thus confirming the role of peroxynitrite overproduction in the development of tolerance to vascular responses induced by organic nitrates. In conclusion, oxidative stress subsequent to prolonged use of organic nitrates, which occurs via nitration of ALDH-2, represents a key event

  19. Structure of Insoluble Rat Sperm Glyceraldehyde-3-phosphate Dehydrogenase (GAPDH) via Heterotetramer Formation with Escherichia coli GAPDH Reveals Target for Contraceptive Design*

    PubMed Central

    Frayne, Jan; Taylor, Abby; Cameron, Gus; Hadfield, Andrea T.

    2009-01-01

    Sperm glyceraldehyde-3-phosphate dehydrogenase has been shown to be a successful target for a non-hormonal contraceptive approach, but the agents tested to date have had unacceptable side effects. Obtaining the structure of the sperm-specific isoform to allow rational inhibitor design has therefore been a goal for a number of years but has proved intractable because of the insoluble nature of both native and recombinant protein. We have obtained soluble recombinant sperm glyceraldehyde-3-phosphate dehydrogenase as a heterotetramer with the Escherichia coli glyceraldehyde-3-phosphate dehydrogenase in a ratio of 1:3 and have solved the structure of the heterotetramer which we believe represents a novel strategy for structure determination of an insoluble protein. A structure was also obtained where glyceraldehyde 3-phosphate binds in the Ps pocket in the active site of the sperm enzyme subunit in the presence of NAD. Modeling and comparison of the structures of human somatic and sperm-specific glyceraldehyde-3-phosphate dehydrogenase revealed few differences at the active site and hence rebut the long presumed structural specificity of 3-chlorolactaldehyde for the sperm isoform. The contraceptive activity of α-chlorohydrin and its apparent specificity for the sperm isoform in vivo are likely to be due to differences in metabolism to 3-chlorolactaldehyde in spermatozoa and somatic cells. However, further detailed analysis of the sperm glyceraldehyde-3-phosphate dehydrogenase structure revealed sites in the enzyme that do show significant difference compared with published somatic glyceraldehyde-3-phosphate dehydrogenase structures that could be exploited by structure-based drug design to identify leads for novel male contraceptives. PMID:19542219

  20. Immunolocalization of betaine aldehyde dehydrogenase in porcine kidney.

    PubMed

    Figueroa-Soto, C G; Lopez-Cervantes, G; Valenzuela-Soto, E M

    1999-05-19

    Polyclonal anti-BADH serum was raised in rabbits against native BADH purified from porcine kidney. The antiserum cross-reacted strongly with BADH purified from kidney, Amaranthus palmierii, and Pseudomona aeuroginosa (1:1000), and weakly with Amaranthus hypochondriacus L (1:100). Antibodies bound to purified native kidney BADH in immunoblots showed a major band of an apparent molecular mass of 340 kDa and a subunit with an apparent molecular mass of 52 kDa. Data on activity assays showed higher activity in cortex sections (81.3 nmol/min/mg protein) than in medulla sections (21.3 nmol/min/mg protein). Immunolocalization of BADH in kidney tissue sections showed that BADH is found in cortex and medulla. In inner medulla, the enzyme was mainly localized in cells surrounding the tubules. Western blot analysis on extracts from the cortex and medulla sections showed higher concentration of BADH protein in cortex than in medulla. These results were in accordance with immunolocalization and activity analysis. Copyright 1999 Academic Press.

  1. Effects of the biodiesel blend fuel on aldehyde emissions from diesel engine exhaust

    NASA Astrophysics Data System (ADS)

    Peng, Chiung-Yu; Yang, Hsi-Hsien; Lan, Cheng-Hang; Chien, Shu-Mei

    Interest in use of biodiesel fuels derived from vegetable oils or animal fats as alternative fuels for petroleum-based diesels has increased due to biodiesels having similar properties of those of diesels, and characteristics of renewability, biodegradability and potential beneficial effects on exhaust emissions. Generally, exhaust emissions of regulated pollutants are widely studied and the results favor biodiesels on CO, HC and particulate emissions; however, limited and inconsistent data are showed for unregulated pollutants, such as carbonyl compounds, which are also important indicators for evaluating available vehicle fuels. For better understanding biodiesel, this study examines the effects of the biodiesel blend fuel on aldehyde chemical emissions from diesel engine exhausts in comparison with those from the diesel fuel. Test engines (Mitsubishi 4M40-2AT1) with four cylinders, a total displacement of 2.84 L, maximum horsepower of 80.9 kW at 3700 rpm, and maximum torque of 217.6 N m at 2000 rpm, were mounted and operated on a Schenck DyNAS 335 dynamometer. Exhaust emission tests were performed several times for each fuel under the US transient cycle protocol from mileages of 0-80,000 km with an interval of 20,000 km, and two additional measurements were carried out at 40,000 and 80,000 km after maintenance, respectively. Aldehyde samples were collected from diluted exhaust by using a constant volume sampling system. Samples were extracted and analyzed by the HPLC/UV system. Dominant aldehydes of both fuels' exhausts are formaldehyde and acetaldehyde. These compounds together account for over 75% of total aldehyde emissions. Total aldehyde emissions for B20 (20% waste cooking oil biodiesel and 80% diesel) and diesel fuels are in the ranges of 15.4-26.9 mg bhp-h -1 and 21.3-28.6 mg bhp-h -1, respectively. The effects of increasing mileages and maintenance practice on aldehyde emissions are insignificant for both fuels. B20 generates slightly less emission than

  2. Quantification of aldehydes emissions from alternative and renewable aviation fuels using a gas turbine engine

    NASA Astrophysics Data System (ADS)

    Li, Hu; Altaher, Mohamed A.; Wilson, Chris W.; Blakey, Simon; Chung, Winson; Rye, Lucas

    2014-02-01

    In this research three renewable aviation fuel blends including two HEFA (Hydrotreated Ester and Fatty Acid) blends and one FAE (Fatty Acids Ethyl Ester) blend with conventional Jet A-1 along with a GTL (Gas To Liquid) fuel have been tested for their aldehydes emissions on a small gas turbine engine. Three strong ozone formation precursors: formaldehyde, acetaldehyde and acrolein were measured in the exhaust at different operational modes and compared to neat Jet A-1. The aim is to assess the impact of renewable and alternative aviation fuels on aldehydes emissions from aircraft gas turbine engines so as to provide informed knowledge for the future deployment of new fuels in aviation. The results show that formaldehyde was a major aldehyde species emitted with a fraction of around 60% of total measured aldehydes emissions for all fuels. Acrolein was the second major emitted aldehyde species with a fraction of ˜30%. Acetaldehyde emissions were very low for all the fuels and below the detention limit of the instrument. The formaldehyde emissions at cold idle were up to two to threefold higher than that at full power. The fractions of formaldehyde were 6-10% and 20% of total hydrocarbon emissions in ppm at idle and full power respectively and doubled on a g kg-1-fuel basis.

  3. Intramolecular homolytic displacements. 30. Functional decarbonylative transformations of aldehydes via homolytically induced decomposition of unsaturated peroxyacetals

    PubMed

    Degueil-Castaing; Moutet; Maillard

    2000-06-30

    Homolytically induced decompositions of unsaturated peroxyacetals, synthesized from aldehydes, gave alkoxyalkoxyl radicals that yielded alkyl radicals by rapid beta-scission. The latter radicals could react with several types of "transfer agents" to smoothly bring about homolytic decarbonylative functional group transformations of aldehydes into halides, hydrocarbons, xanthates, alkanenitriles, 2-alkyl-3-chloromaleic anhydrides, 1-phenylalk-1-ynes, and ethyl 2-alkylpropenoates.

  4. Indoor aldehydes concentration and emission rate of formaldehyde in libraries and private reading rooms

    NASA Astrophysics Data System (ADS)

    Kim, Jeonghoon; Kim, Seojin; Lee, Kiyoung; Yoon, Dongwon; Lee, Jiryang; Ju, DaeYoung

    2013-06-01

    Aldehydes are of particularly interest due to their potential adverse impact on human health. Formaldehyde is one of the most abundant indoor pollutants. To improve indoor air quality, identifying and removing the major emission sources of formaldehyde would be desirable. The purposes of this study were to determine aldehyde concentrations in libraries and reading rooms and to identify emission sources of formaldehyde in private reading rooms. Indoor aldehyde concentrations were quantified at 66 facilities, including public libraries, children's libraries, public reading rooms, and private reading rooms, in the Seoul metropolitan area. Emission fluxes of formaldehyde from the surfaces of desks, chairs, floors, walls, and ceilings in 19 private reading rooms were measured using a passive emission colorimetric sensor. Indoor aldehyde (formaldehyde, acetaldehyde, propioaldehyde, benzaldehyde, and hexaldehyde) levels were significantly higher than outdoor levels. Indoor formaldehyde geometric mean concentrations in private reading rooms (119.3 μg m-3) were significantly higher than in public libraries (29.2 μg m-3), children's libraries (29.3 μg m-3), and public reading rooms (40.8 μg m-3). Indoor formaldehyde levels were associated with relative humidity. In private reading rooms, the emission rates from desks (255.5 ± 214.8 μg h-1) and walls (231.7 ± 192.3 μg h-1) were significantly higher than that from chairs (79.6 ± 88.5 μg h-1). Desks (31%) and walls (29%) were the major emission sources of formaldehyde in 14 facilities in which measurements exceeded the indoor standard of 100 μg m-3. The age of interior materials was a significant factor for indoor formaldehyde emission flux. Controlling the emission rates of desks and walls is recommended to improve formaldehyde concentrations in private reading rooms.

  5. Identification and functional evaluation of the reductases and dehydrogenases from Saccharomyces cerevisiae involved in vanillin resistance.

    PubMed

    Wang, Xinning; Liang, Zhenzhen; Hou, Jin; Bao, Xiaoming; Shen, Yu

    2016-04-01

    Vanillin, a type of phenolic released during the pre-treatment of lignocellulosic materials, is toxic to microorganisms and therefore its presence inhibits the fermentation. The vanillin can be reduced to vanillyl alcohol, which is much less toxic, by the ethanol producer Saccharomyces cerevisiae. The reducing capacity of S. cerevisiae and its vanillin resistance are strongly correlated. However, the specific enzymes and their contribution to the vanillin reduction are not extensively studied. In our previous work, an evolved vanillin-resistant strain showed an increased vanillin reduction capacity compared with its parent strain. The transcriptome analysis suggested the reductases and dehydrogenases of this vanillin resistant strain were up-regulated. Using this as a starting point, 11 significantly regulated reductases and dehydrogenases were selected in the present work for further study. The roles of these reductases and dehydrogenases in the vanillin tolerance and detoxification abilities of S. cerevisiae are described. Among the candidate genes, the overexpression of the alcohol dehydrogenase gene ADH6, acetaldehyde dehydrogenase gene ALD6, glucose-6-phosphate 1-dehydrogenase gene ZWF1, NADH-dependent aldehyde reductase gene YNL134C, and aldo-keto reductase gene YJR096W increased 177, 25, 6, 15, and 18 % of the strain μmax in the medium containing 1 g L(-1) vanillin. The in vitro detected vanillin reductase activities of strain overexpressing ADH6, YNL134C and YJR096W were notably higher than control. The vanillin specific reduction rate increased by 8 times in ADH6 overexpressed strain but not in YNL134C and YJR096W overexpressed strain. This suggested that the enzymes encoded by YNL134C and YJR096W might prefer other substrate and/or could not show their effects on vanillin on the high background of Adh6p in vivo. Overexpressing ALD6 and ZWF1 mainly increased the [NADPH]/[NADP(+)] and [GSH]/[GSSG] ratios but not the vanillin reductase activities. Their

  6. Short-Chain 3-Hydroxyacyl-Coenzyme A Dehydrogenase Associates with a Protein Super-Complex Integrating Multiple Metabolic Pathways

    PubMed Central

    Narayan, Srinivas B.; Master, Stephen R.; Sireci, Anthony N.; Bierl, Charlene; Stanley, Paige E.; Li, Changhong; Stanley, Charles A.; Bennett, Michael J.

    2012-01-01

    Proteins involved in mitochondrial metabolic pathways engage in functionally relevant multi-enzyme complexes. We previously described an interaction between short-chain 3-hydroxyacyl-coenzyme A dehydrogenase (SCHAD) and glutamate dehydrogenase (GDH) explaining the clinical phenotype of hyperinsulinism in SCHAD-deficient patients and adding SCHAD to the list of mitochondrial proteins capable of forming functional, multi-pathway complexes. In this work, we provide evidence of SCHAD's involvement in additional interactions forming tissue-specific metabolic super complexes involving both membrane-associated and matrix-dwelling enzymes and spanning multiple metabolic pathways. As an example, in murine liver, we find SCHAD interaction with aspartate transaminase (AST) and GDH from amino acid metabolic pathways, carbamoyl phosphate synthase I (CPS-1) from ureagenesis, other fatty acid oxidation and ketogenesis enzymes and fructose-bisphosphate aldolase, an extra-mitochondrial enzyme of the glycolytic pathway. Most of the interactions appear to be independent of SCHAD's role in the penultimate step of fatty acid oxidation suggesting an organizational, structural or non-enzymatic role for the SCHAD protein. PMID:22496890

  7. [Polymorphism of alcohol dehydrogenase gene ADH1B in eastern Slavic and Iranian-speaking populations].

    PubMed

    2005-11-01

    Frequencies of alleles and genotypes for alcohol dehydrogenase gene ADH1B (arg47his polymorphism), associated with alcohol tolerance/sensitivity, were determined. It was demonstrated that the frequency of allele ADH1B*47his, corresponding to atypical alcohol dehydrogenase variant in Russians, Ukrainians, Iranians, and mountain-dwellers of the Pamirs constituted 3, 7, 24, and 22%, respectively. The frequencies established were consistent with the allele frequency distribution pattern among the populations of Eurasia. Russians and Ukrainians were indistinguishable from other European populations relative to the frequency of allele ADH1B*47his, and consequently, relative to specific features of ethanol metabolic pathways. The data obtained provide refinement of the geographic pattern of ADH1B*47his frequency distribution in Eurasia.

  8. The investigation of plasma glucose-6-phosphate dehydrogenase, 6-phoshogluconate dehydrogenase, glutathione reductase in premenauposal patients with iron deficiency anemia.

    PubMed

    Ozcicek, Fatih; Aktas, Mehmet; Türkmen, Kultigin; Coban, T Abdulkadir; Cankaya, Murat

    2014-07-01

    Iron is an essential element that is necessary for all cells in the body. Iron deficiency anemia (IDA) is one of the most common nutritional disorders in both developed and developing countries. The glutathione pathway is paramount to antioxidant defense and glucose-6-phosphate dehydrogenase (G6PD)-deficient cells do not cope well with oxidative damage. The goal of this study was to check the activities of G6PD, 6-phosphogluconate dehydrogenase, glutathione reductase in patients with IDA. We analyzed the plasma samples of 102 premenopausal women with IDA and 88 healthy control subjects. Glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase activity as compared to the reduction of NADP +, glutathione reductase activity was performed based on the oxidation of NADPH. 2 ml of plasma were used in all analyzes. SPSS program was used for all of the statistical analysis. Diagnosis of iron deficiency in patients belonging to the analysis of blood were ferritin 3.60 ± 2.7 ng / mL, hemoglobin 9.4 ± 1.5 mg / dl and hematocrit 30.7 ± 4.1% ratio; in healthy subjects ferritin 53.5 ± 41.7 ng/ml, hemoglobin level 13.9 ± 1.3 mg / dl and hematocrit ratio 42 ± 3.53%. When compared to healthy subjects the glutathione reductase level (P<0.001) was found to be significantly higher in patients with IDA. IDA patients with moderate and severe anemia had lower GR activity when compared to IDA patients with mild anemia. But the plasma levels of glucose-6-phosphate dehydrogenase (P<0,600) and 6-phosphogluconate dehydrogenase (P<0,671) did not show any differences between healthy subjects and in patients with IDA. It was shown that Glucose-6-Phosphate Dehydrogenase and 6-Phosphogluconate Dehydrogenase have no effect on iron-deficiency anemia in patients. The plasma GR levels of premenopausal women with IDA were found to be higher compared to healthy subjects, which could be secondary to erythrocyte protection against oxidative stress being commonly seen in IDA.

  9. Enzymatic transformation of hydrocarbons by methanotrophic organisms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patel, R.N.; Hou, C.T.

    Soluble methane monooxygenase from a facultative methane-utilizing organism, Methylobacterium sp. CRL-26 or R6, catalyzed the NAD(P)H-dependent epoxidation/hydroxylation of a variety of hydrocarbons, including terminal alkenes, internal alkenes, substituted alkenes, branch-chain alkenes, alkanes (C1-C8), substituted alkanes, branch-chain alkanes, carbon monoxide, ether, cyclic and aromatic compounds. The NAD -linked dehydrogenases such as formate dehydrogenase or secondary alcohol dehydrogenase in the presence of formate or secondary alcohol, respectively, regenerated NAD/NADH required for the methane monooxygenase in a coupled enzymes reactions. Oxidation of secondary alcohols to the corresponding methylketones in methanotrophs is catalyzed by an NAD -dependent, zinc-containing, secondary alcohol hydrogenase. Primary alcohols weremore » oxidized to the corresponding aldehydes by a phenazine methosulfate-dependent, pyrollo quinoline quinone (methoxatin or PQQ) containing, methanol dehydrogenase. Oxidation of aldehydes (C1 to C10) to the corresponding carboxylic acids is catalyzed by a heme-containing aldehyde dehydrogenase. Methanotrophs have been considered potentially useful for single cell protein (SCP), amino acids, and biopolymer production at the expense of growth on cheap and readily available C1 compounds. 80 references, 1 figure, 6 tables.« less

  10. Silica gel promotes reductions of aldehydes and ketones by N-heterocyclic carbene boranes.

    PubMed

    Taniguchi, Tsuyoshi; Curran, Dennis P

    2012-09-07

    N-Heterocyclic carbene boranes (NHC-boranes) such as 1,3-dimethylimidazol-2-ylidine trihydridoborane (diMe-Imd-BH(3)) serve as practical hydride donors for the reduction of aldehydes and ketones in the presence of silica gel. Primary and secondary alcohols are formed in good yields under ambient conditions. Aldehydes are selectively reduced in the presence of ketones. One, two, or even all three of the boron hydrides can be transferred. The process is attractive because all the components are stable and easy to handle and because both the reaction and isolation procedures are convenient.

  11. Comparison of aldehyde emissions simulation with FTIR measurements in the exhaust of a spark ignition engine fueled by ethanol

    NASA Astrophysics Data System (ADS)

    Zarante, Paola Helena Barros; Sodré, José Ricardo

    2018-07-01

    This work presents a numerical simulation model for aldehyde formation and exhaust emissions from ethanol-fueled spark ignition engines. The aldehyde simulation model was developed using FORTRAN software, with the input data obtained from the dedicated engine cycle simulation software AVL BOOST. The model calculates formaldehyde and acetaldehyde concentrations from post-flame partial oxidation of methane, ethane and unburned ethanol. The calculated values were compared with experimental data obtained from a mid-size sedan powered by a 1.4-l spark ignition engine, tested on a chassis dynamometer. Exhaust aldehyde concentrations were determined using a Fourier Transform Infrared (FTIR) Spectroscopy analyzer. In general, the results demonstrate that the concentrations of aldehydes and the source elements increased with engine speed and exhaust gas temperature. The measured acetaldehyde concentrations showed values from 3 to 6 times higher than formaldehyde in the range studied. The model could predict reasonably well the qualitative experimental trends, with the quantitative results showing a maximum discrepancy of 39% for acetaldehyde concentration and 21 ppm for exhaust formaldehyde.

  12. Comparison of aldehyde emissions simulation with FTIR measurements in the exhaust of a spark ignition engine fueled by ethanol

    NASA Astrophysics Data System (ADS)

    Zarante, Paola Helena Barros; Sodré, José Ricardo

    2018-02-01

    This work presents a numerical simulation model for aldehyde formation and exhaust emissions from ethanol-fueled spark ignition engines. The aldehyde simulation model was developed using FORTRAN software, with the input data obtained from the dedicated engine cycle simulation software AVL BOOST. The model calculates formaldehyde and acetaldehyde concentrations from post-flame partial oxidation of methane, ethane and unburned ethanol. The calculated values were compared with experimental data obtained from a mid-size sedan powered by a 1.4-l spark ignition engine, tested on a chassis dynamometer. Exhaust aldehyde concentrations were determined using a Fourier Transform Infrared (FTIR) Spectroscopy analyzer. In general, the results demonstrate that the concentrations of aldehydes and the source elements increased with engine speed and exhaust gas temperature. The measured acetaldehyde concentrations showed values from 3 to 6 times higher than formaldehyde in the range studied. The model could predict reasonably well the qualitative experimental trends, with the quantitative results showing a maximum discrepancy of 39% for acetaldehyde concentration and 21 ppm for exhaust formaldehyde.

  13. Binding, hydration, and decarboxylation of the reaction intermediate glutaconyl-coenzyme A by human glutaryl-CoA dehydrogenase.

    PubMed

    Westover, J B; Goodman, S I; Frerman, F E

    2001-11-20

    Glutaconyl-coenzyme A (CoA) is the presumed enzyme-bound intermediate in the oxidative decarboxylation of glutaryl-CoA that is catalyzed by glutaryl-CoA dehydrogenase. We demonstrated glutaconyl-CoA bound to glutaryl-CoA dehydrogenase after anaerobic reduction of the dehydrogenase with glutaryl-CoA. Glutaryl-CoA dehydrogenase also has intrinsic enoyl-CoA hydratase activity, a property of other members of the acyl-CoA dehydrogenase family. The enzyme rapidly hydrates glutaconyl-CoA at pH 7.6 with a k(cat) of 2.7 s(-1). The k(cat) in the overall oxidation-decarboxylation reaction at pH 7.6 is about 9 s(-1). The binding of glutaconyl-CoA was quantitatively assessed from the K(m) in the hydratase reaction, 3 microM, and the K(i), 1.0 microM, as a competitive inhibitor of the dehydrogenase. These values compare with K(m) and K(i) of 4.0 and 12.9 microM, respectively, for crotonyl-CoA. Glu370 is the general base catalyst in the dehydrogenase that abstracts an alpha-proton of the substrate to initiate the catalytic pathway. The mutant dehydrogenase, Glu370Gln, is inactive in the dehydrogenation and the hydratase reactions. However, this mutant dehydrogenase decarboxylates glutaconyl-CoA to crotonyl-CoA without oxidation-reduction reactions of the dehydrogenase flavin. Addition of glutaconyl-CoA to this mutant dehydrogenase results in a rapid, transient increase in long-wavelength absorbance (lambda(max) approximately 725 nm), and crotonyl-CoA is found as the sole product. We propose that this 725 nm-absorbing species is the delocalized crotonyl-CoA anion that follows decarboxylation and that the decay is the result of slow protonation of the anion in the absence of the general acid catalyst, Glu370(H(+)). In the absence of detectable oxidation-reduction, the data indicate that oxidation-reduction of the dehydrogenase flavin is not essential for decarboxylation of glutaconyl-CoA.

  14. Direct catalytic asymmetric alpha-amination of aldehydes.

    PubMed

    List, Benjamin

    2002-05-22

    The first direct catalytic asymmetric alpha-amination of aldehydes is described herein. alpha-Unbranched aldehydes react in this novel proline-catalyzed reaction with dialkyl azodicarboxylates to give alpha-amino aldehydes in excellent yields and enantioselectivities.

  15. CvADH1, a member of short-chain alcohol dehydrogenase family, is inducible by gibberellin and sucrose in developing watermelon seeds.

    PubMed

    Kim, Joonyul; Kang, Hong-Gyu; Jun, Sung-Hoon; Lee, Jinwon; Yim, Jieun; An, Gynheung

    2003-01-01

    To understand the molecular mechanisms that control seed formation, we selected a seed-preferential gene (CvADH1) from the ESTs of developing watermelon seeds. RNA blot analysis and in situ localization showed that CvADH1 was preferentially expressed in the nucellar tissue. The CvADH1 protein shared about 50% homology with short-chain alcohol dehydrogenase including ABA2 in Arabidopsis thaliana, stem secoisolariciresinol dehydrogenase in Forsythia intermedia, and 3beta-hydroxysterol dehydrogenase in Digitalis lanata. We investigated gene-expression levels in seeds from both normally pollinated fruits and those made parthenocarpic via N-(2-chloro-4-pyridyl)-N'-phenylurea treatment, the latter of which lack zygotic tissues. Whereas the transcripts of CvADH1 rapidly started to accumulate from about the pre-heart stage in normal seeds, they were not detectable in the parthenocarpic seeds. Treating the parthenogenic fruit with GA(3) strongly induced gene expression, up to the level accumulated in pollinated seeds. These results suggest that the CvADH1 gene is induced in maternal tissues by signals made in the zygotic tissues, and that gibberellin might be one of those signals. We also observed that CvADH1 expression was induced by sucrose in the parthenocarpic seeds. Therefore, we propose that the CvADH1 gene is inducible by gibberellin, and that sucrose plays an important role in the maternal tissues of watermelon during early seed development.

  16. A soft tissue adhesive based on aldehyde-sodium alginate and amino-carboxymethyl chitosan preparation through the Schiff reaction

    NASA Astrophysics Data System (ADS)

    Wu, Yu; Yuan, Liu; Sheng, Nai-an; Gu, Zi-qi; Feng, Wen-hao; Yin, Hai-yue; Morsi, Yosry; Mo, Xiu-mei

    2017-09-01

    Sodium alginate and carboxymethyl chitosan have been extensively applied in tissue engineering and other relative fields due to their low price and excellent biocompatibility. In this paper, we oxidized sodium alginate with sodium periodate to convert 1,2-hydroxyl groups into aldehyde groups to get aldehyde-sodium alginate (ASA). Carboxymethyl chitosan was modified with ethylenediamine (ED) in the presence of water-soluble N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) to introduce additional amino groups to get amino-carboxymethyl chitosan (A-CS). Upon mixing the A-SA and A-CS aqueous solutions together, a gel rapidly formed based on the Schiff's base reaction between aldehyde groups in A-SA and amino groups in A-CS. FTIR analysis confirmed the characteristic peak of Schiff's base group in the hydrogel. It was confirmed that the gelation time be dependent on the aldehyde group content in A-SA and amino group content in A-CS. The fasted hydrogel formation takes place within 10 min. The data of bonding strength and cytotoxicity measurement also showed that the hydrogel had good adhesion and biocompatibility. All these results support that this gel has the potential as soft tissue adhesive.

  17. Atmospheric measurements of hydroperoxides and aldehydes during field campaigns : new results due to improvement of measurements techniques

    NASA Astrophysics Data System (ADS)

    François, S.; Sowka, I.; Poulain, L.; Monod, A.; Wortham, H.

    2003-04-01

    Hydroperoxides and aldehydes are considered as atmospheric reservoirs of OH, HO_2 and RO_2 radicals and can reflect the oxidizing levels of the atmosphere. They are considered as important gas phase photo-oxidants present in the atmosphere. However, the atmospheric role of these compounds can vary from one species to another, therefore it is essential to investigate their measurement and speciation in the atmosphere. Atmospheric measurements were realized during two different field campaigns in the Marseilles area (France). Hydroperoxides were trapped in aqueous phase, with a glass coil and analyzed by HPLC/fluorescence detector with post column derivatization. Aldehydes were trapped in a liquid phase containing 2-4 DNPH, with a mist chamber and analyzed by HPLC/UV. The analytical techniques provided individual separation and quantification of seven hydroperoxides (hydrogen peroxide, hydroxymethyl hydroperoxide, bis(hydroxymethyl) peroxide, 1-hydroxyethyl hydroperoxide, methyl hydroperoxide, ethyl hydroperoxide and peroxyacetic acid) and eleven volatile aldehydes (formaldehyde, acetaldehyde, acrolein, acetone, propionaldehyde, crotonaldehyde, butyraldehyde, benzaldehyde, glyoxal, valeraldehyde and methylglyoxal). The first field campaign was part of the ESCOMPTE project (June 4th to July 16th 2001). During this campaign five different sampling sites, at low altitudes (<= 285 m), were investigated (maritime, urban, sub-industrial, biogenic and rural sites) and atmospheric measurements were realized during photochemical air pollution events. The second field campaign was part of the BOND project (July 2nd to July 14th 2002). Atmospheric measurements of hydroperoxides were carried out on one biogenic site, at altitude 690 m. The measurement system was improved allowing online sampling and analysis. During these field campaigns collection efficiencies were better than 96% for hydroperoxides, and from 78% to 96% for aldehydes. Detection limits were between 7,3× 10-3

  18. Analysis of endogenous aldehydes in human urine by static headspace gas chromatography-mass spectrometry.

    PubMed

    Serrano, María; Gallego, Mercedes; Silva, Manuel

    2016-03-11

    Endogenous aldehydes (EAs) generated during oxidative stress and cell processes are associated with many pathogenic and toxicogenic processes. The aim of this research was to develop a solvent-free and automated analytical method for the determination of EAs in human urine using a static headspace generator sampler coupled with gas chromatography-mass spectrometry (HS-GC-MS). Twelve significant EAs used as markers of different biochemical and physiological processes, namely short- and medium-chain alkanals, α,β-unsaturated aldehydes and dicarbonyl aldehydes have been selected as target analytes. Human urine samples (no dilution is required) were derivatized with O-2,3,4,5,6-pentafluorobenzylhydroxylamine in alkaline medium (hydrogen carbonate-carbonate buffer, pH 10.3). The HS-GC-MS method developed renders an efficient tool for the sensitive and precise determination of EAs in human urine with limits of detection from 1 to 15ng/L and relative standard deviations, (RSDs) from 6.0 to 7.9%. Average recoveries by enriching urine samples ranged between 92 and 95%. Aldehydes were readily determined at 0.005-50μg/L levels in human urine from healthy subjects, smokers and diabetic adults. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. A general palladium-catalyzed carbonylative synthesis of chromenones from salicylic aldehydes and benzyl chlorides.

    PubMed

    Wu, Xiao-Feng; Wu, Lipeng; Jackstell, Ralf; Neumann, Helfried; Beller, Matthias

    2013-09-09

    Cute CO! An interesting and straightforward procedure for the carbonylative synthesis of chromenones from readily available salicylic aldehydes and benzyl chlorides has been developed (see scheme; DPPP = 1,3-bis(diphenylphosphino)propane). In the presence of a palladium catalyst, various coumarins were produced in good to excellent yields. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Characterization of human DHRS4: an inducible short-chain dehydrogenase/reductase enzyme with 3beta-hydroxysteroid dehydrogenase activity.

    PubMed

    Matsunaga, Toshiyuki; Endo, Satoshi; Maeda, Satoshi; Ishikura, Shuhei; Tajima, Kazuo; Tanaka, Nobutada; Nakamura, Kazuo T; Imamura, Yorishige; Hara, Akira

    2008-09-15

    Human DHRS4 is a peroxisomal member of the short-chain dehydrogenase/reductase superfamily, but its enzymatic properties, except for displaying NADP(H)-dependent retinol dehydrogenase/reductase activity, are unknown. We show that the human enzyme, a tetramer composed of 27kDa subunits, is inactivated at low temperature without dissociation into subunits. The cold inactivation was prevented by a mutation of Thr177 with the corresponding residue, Asn, in cold-stable pig DHRS4, where this residue is hydrogen-bonded to Asn165 in a substrate-binding loop of other subunit. Human DHRS4 reduced various aromatic ketones and alpha-dicarbonyl compounds including cytotoxic 9,10-phenanthrenequinone. The overexpression of the peroxisomal enzyme in cultured cells did not increase the cytotoxicity of 9,10-phenanthrenequinone. While its activity towards all-trans-retinal was low, human DHRS4 efficiently reduced 3-keto-C(19)/C(21)-steroids into 3beta-hydroxysteroids. The stereospecific conversion to 3beta-hydroxysteroids was observed in endothelial cells transfected with vectors expressing the enzyme. The mRNA for the enzyme was ubiquitously expressed in human tissues and several cancer cells, and the enzyme in HepG2 cells was induced by peroxisome-proliferator-activated receptor alpha ligands. The results suggest a novel mechanism of cold inactivation and role of the inducible human DHRS4 in 3beta-hydroxysteroid synthesis and xenobiotic carbonyl metabolism.

  1. Retinoic acid biosynthesis catalyzed by retinal dehydrogenases relies on a rate-limiting conformational transition associated with substrate recognition

    PubMed Central

    Bchini, Raphaël; Vasiliou, Vasilis; Branlant, Guy; Talfournier, François; Rahuel-Clermont, Sophie

    2012-01-01

    Retinoic acid (RA), a metabolite of vitamin A, exerts pleiotropic effects throughout life in vertebrate organisms. Thus, RA action must be tightly regulated through the coordinated action of biosynthetic and degradating enzymes. The last step of retinoic acid biosynthesis is irreversibly catalyzed by the NAD-dependent retinal dehydrogenases (RALDH), which are members of the aldehyde dehydrogenase (ALDH) superfamily. Low intracellular retinal concentrations imply efficient substrate molecular recognition to ensure high affinity and specificity of RALDHs for retinal. This study addresses the molecular basis of retinal recognition in human ALDH1A1 (or RALDH1) and rat ALDH1A2 (or RALDH2), through the comparison of the catalytic behavior of retinal analogs and use of the fluorescence properties of retinol. We show that, in contrast to long chain unsaturated substrates, the rate-limiting step of retinal oxidation by RALDHs is associated with acylation. Use of the fluorescence resonance energy transfer upon retinol interaction with RALDHs provides evidence that retinal recognition occurs in two steps: binding into the substrate access channel, and a slower structural reorganization with a rate constant of the same magnitude as the kcat for retinal oxidation: 0.18 vs. 0.07 s−1 and 0.25 vs. 0.1 s−1 for ALDH1A1 and ALDH1A2, respectively. This suggests that the conformational transition of the RALDH-retinal complex significantly contributes to the rate-limiting step that controls the kinetics of retinal oxidation, as a prerequisite for the formation of a catalytically competent Michaelis complex. This conclusion is consistent with the general notion that structural flexibility within the active site of ALDH enzymes has been shown to be an integral component of catalysis. PMID:23220587

  2. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... containing aldehydes. 24.183 Section 24.183 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... distillates containing aldehydes. Distillates containing aldehydes may be received on wine premises for use in... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are received...

  3. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... containing aldehydes. 24.183 Section 24.183 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... distillates containing aldehydes. Distillates containing aldehydes may be received on wine premises for use in... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are received...

  4. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... containing aldehydes. 24.183 Section 24.183 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... distillates containing aldehydes. Distillates containing aldehydes may be received on wine premises for use in... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are received...

  5. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... containing aldehydes. 24.183 Section 24.183 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... distillates containing aldehydes. Distillates containing aldehydes may be received on wine premises for use in... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are received...

  6. Facile preparation of oxazole-4-carboxylates and 4-ketones from aldehydes using 3-oxazoline-4-carboxylates as intermediates.

    PubMed

    Murai, Kenichi; Takahara, Yusuke; Matsushita, Tomoyo; Komatsu, Hideyuki; Fujioka, Hiromichi

    2010-08-06

    A novel 2-step synthesis of oxazole-4-carboxylates from aldehydes was developed, which is characterized by the utilization of 3-oxazoline-4-carboxylates as synthetic intermediates. The facile preparation of 4-keto-oxazole derivatives from 3-oxazoline-4-carboxylates based on their interesting reactivity toward Grignard reagents is also described.

  7. Diastereoselective addition of 2H-2-oxo-1,4,2-oxazaphosphinanes to aldehydes and imines.

    PubMed

    Pirat, Jean-Luc; Monbrun, Jérôme; Virieux, David; Volle, Jean-Noël; Tillard, Monique; Cristau, Henri-Jean

    2005-09-02

    [reaction: see text] Diastereoselective additions of 2-hydrogeno-2-oxo-1,4,2-oxazaphosphinanes to aldehydes and imines are described. alpha,alpha'-Diaminophosphinic and alpha-amino-alpha'-hydroxyphosphinic derivatives were obtained with de's ranging from 24 to 90%.

  8. 9-Hydroxyprostaglandin dehydrogenase activity in the adult rat kidney. Regional distribution and sub-fractionation.

    PubMed

    Asciak, C P; Domazet, Z

    1975-02-20

    1. Catabolism of prostaglandin F2alpha in the adult rat kidney takes place by the following sequence of enzymatic steps: (1) 15-hydroxyprostaglandin dehydrogenase; (2) prostaglandin delta13-reductase; and (3) 9-hydroxyprostaglandin dehydrogenase. 2. 9-Hydroxyprostaglandin dehydrogenase activity was highest in the cortex with lesser amounts in the medulla and negligible activity detected in the papilla. A similar distribution was observed for 15-hydroxyprostaglandin dehydrogenase and prostaglandin delta13-reductase. 3. Most of the 9-hydroxyprostaglandin dehydrogenase activity in the homogenate was found in the high-speed supernatant as also observed for 15-hydroxyprostaglandin dehydrogenase and prostaglandin delta13-reductase. 4. These observations indicate that the rat kidney contains an abundance of prostaglandin-catabolising enzymes which favour formation of metabolites of the E-type.

  9. A heterobimetallic Ga/Yb-Schiff base complex for catalytic asymmetric alpha-addition of isocyanides to aldehydes.

    PubMed

    Mihara, Hisashi; Xu, Yingjie; Shepherd, Nicholas E; Matsunaga, Shigeki; Shibasaki, Masakatsu

    2009-06-24

    Development of a new heterobimetallic Ga(O-iPr)(3)/Yb(OTf)(3)/Schiff base 2d complex for catalytic asymmetric alpha-additions of isocyanides to aldehydes is described. Schiff base 2d derived from o-vanillin was suitable to utilize cationic rare earth metal triflates with good Lewis acidity in bimetallic Schiff base catalysis. The Ga(O-iPr)(3)/Yb(OTf)(3)/Schiff base 2d complex promoted asymmetric alpha-additions of alpha-isocyanoacetamides to aryl, heteroaryl, alkenyl, and alkyl aldehydes in good to excellent enantioselectivity (88-98% ee).

  10. Bicarbonate dependency of betaine synthesis in cultured LLC-PK1 cells.

    PubMed

    Moeckel, G W; Lien, Y H

    1994-03-01

    Betaine, one of the major renal organic osmolytes, is synthesized from choline by choline dehydrogenase (EC 1.1.99.1) and betaine-aldehyde dehydrogenase (EC 1.2.1.8) in the kidney. A recent in vitro study has shown that betaine synthesis by renal cortical homogenate is dependent on millimolar amounts of bicarbonate. The present study was aimed to investigate the bicarbonate dependency of betaine formation in cultured LLC-PK1 cells. The data show that betaine formation increases in accordance with a rise in extracellular bicarbonate levels. The measured quantities of [14C]betaine synthesis ranged from 13.4 +/- 1.5 (4.6 mM HCO3-) to 38.0 +/- 1.4 pmol.micrograms protein-1.h-1 (24 mM HCO3-). The carbonic anhydrase inhibitor acetazolamide, added to the incubation medium to block bicarbonate transport, reduced betaine synthesis from choline by 41-49%. We conclude that betaine synthesis in LLC-PK1 cells is dependent on extracellular bicarbonate levels and is reduced by the inhibition of carbonic anhydrase. Because betaine accumulates in renal medulla during antidiuresis, our observations suggest a possible link between acid-base homeostasis and concentration mechanisms in the kidney.

  11. New HPLC methods to quantitate terpenoid aldehydes in foliage of cotton (Gossypium)

    USDA-ARS?s Scientific Manuscript database

    The cotton plant (Gossypium) produces protective terpenoid aldehydes in lysigenous pigment glands. These terpenoids include hemigossypolone, hemigossypolone-6-methyl ether, gossypol, gossypol-6-methyl ether, gossypol-6,6'-dimethyl ether, heliocides H1, H2, H3 and H4, and heliocides B1, B2, B3 and B4...

  12. Catalytic Mechanism of Short Ethoxy Chain Nonylphenol Dehydrogenase Belonging to a Polyethylene Glycol Dehydrogenase Group in the GMC Oxidoreductase Family

    PubMed Central

    Liu, Xin; Ohta, Takeshi; Kawabata, Takeshi; Kawai, Fusako

    2013-01-01

    Ethoxy (EO) chain nonylphenol dehydrogenase (NPEO-DH) from Ensifer sp. AS08 and EO chain octylphenol dehydrogenase from Pseudomonas putida share common molecular characteristics with polyethylene glycol (PEG) dehydrogenases (PEG-DH) and comprise a PEG-DH subgroup in the family of glucose-methanol-choline (GMC) oxidoreductases that includes glucose/alcohol oxidase and glucose/choline dehydrogenase. Three-dimensional (3D) molecular modeling suggested that differences in the size, secondary structure and hydropathy in the active site caused differences in their substrate specificities toward EO chain alkylphenols and free PEGs. Based on 3D molecular modeling, site-directed mutagenesis was utilized to introduce mutations into potential catalytic residues of NPEO-DH. From steady state and rapid kinetic characterization of wild type and mutant NPEO-DHs, we can conclude that His465 and Asn507 are directly involved in the catalysis. Asn507 mediates the transfer of proton from a substrate to FAD and His465 transfers the same proton from the reduced flavin to an electron acceptor. PMID:23306149

  13. Catalytic mechanism of short ethoxy chain nonylphenol dehydrogenase belonging to a polyethylene glycol dehydrogenase group in the GMC oxidoreductase family.

    PubMed

    Liu, Xin; Ohta, Takeshi; Kawabata, Takeshi; Kawai, Fusako

    2013-01-10

    Ethoxy (EO) chain nonylphenol dehydrogenase (NPEO-DH) from Ensifer sp. AS08 and EO chain octylphenol dehydrogenase from Pseudomonas putida share common molecular characteristics with polyethylene glycol (PEG) dehydrogenases (PEG-DH) and comprise a PEG-DH subgroup in the family of glucose-methanol-choline (GMC) oxidoreductases that includes glucose/alcohol oxidase and glucose/choline dehydrogenase. Three-dimensional (3D) molecular modeling suggested that differences in the size, secondary structure and hydropathy in the active site caused differences in their substrate specificities toward EO chain alkylphenols and free PEGs. Based on 3D molecular modeling, site-directed mutagenesis was utilized to introduce mutations into potential catalytic residues of NPEO-DH. From steady state and rapid kinetic characterization of wild type and mutant NPEO-DHs, we can conclude that His465 and Asn507 are directly involved in the catalysis. Asn507 mediates the transfer of proton from a substrate to FAD and His465 transfers the same proton from the reduced flavin to an electron acceptor.

  14. n-Aldehydes (C6-C10) in snow samples collected at the high alpine research station Jungfraujoch during CLACE 5

    NASA Astrophysics Data System (ADS)

    Sieg, K.; Starokozhev, E.; Fries, E.; Sala, S.; Püttmann, W.

    2009-04-01

    C6-C10 n-aldehydes were analyzed in samples of freshly fallen snow collected at the high alpine research station Jungfraujoch, Switzerland, during the Cloud and Aerosol Characterization Experiments (CLACE) 5 in February and March 2006. Sampling was carried out on the Sphinx platform. Headspace - solid phase dynamic extraction (HS-SPDE) combined with gas chromatography/mass spectrometry (GC/MS) was used to quantify n-aldehydes in melted snow samples. n-Hexanal was identified as the most abundant n-aldehyde (median concentration 1.324 µg L-1) followed by n-nonanal, n-decanal, n-octanal and n-heptanal (median concentrations 1.239, 0.863, 0.460 and 0.304 µg L-1, respectively). A wide range of concentrations of n-aldehydes was found in snow samples from Jungfraujoch, even for samples collected at the same time during the same snowfall event. According to their physical and chemical characteristics, n-aldehydes are expected to be primarily linked to aerosol particles in the atmosphere suggesting the uptake of n-aldehydes into snow via the particle phase. Particle scavenging can occur during snow formation in clouds. The high concentration variations of the n-aldehydes among the snow samples can be explained assuming that aerosol particles, which are loaded with n-aldehydes, are heterogeneously distributed throughout the snow samples. Higher median concentrations of all n-aldehydes were observed when air masses reached Jungfraujoch from the north-northwest in comparison to air masses arriving from the southeast-southwest. The sources of atmospheric n-aldehydes present at Jungfraujoch are most likely to be related to direct and indirect biogenic emissions. The presence of n-aldehydes as semivolatile constituents of direct biogenic emissions from vegetation has been reported previously in studies of Ciccioli et al. [1], Yokouchi et al. [2] and Kesselmeier and Staudt [3]. The distribution pattern of the n-aldehydes in emissions from vegetation largely matches with the n-aldehyde

  15. Highly diastereoselective reductive coupling of 2-bromo-2,3,3,3-tetrafluoropropanamide with aldehydes promoted by triphenylphosphine-titanium(IV) isopropoxide. An efficient route to the synthesis of erythro-alpha-fluoro-alpha-(trifluoromethyl)-beta-hydroxy amides.

    PubMed

    Sato, Kei; Sekiguchi, Takashi; Ishihara, Takashi; Konno, Tsutomu; Yamanaka, Hiroki

    2004-07-23

    The reductive coupling reaction of N-methoxy-N-methyl-2-bromo-2,3,3,3-tetrafluoropropanamide (Weinreb amide) with various aldehydes under the influence of the combined reagent, 1.2 equiv each of triphenylphosphine and titanium(IV) isopropoxide, took place smoothly at ambient temperature to give the corresponding alpha-fluoro-alpha-(trifluoromethyl)-beta-hydroxy amides in a highly erythro-selective manner. The high erythro selectivity was also obtained even by employing a combination of triphenylphosphine (1.2 equiv) and a catalytic amount of titanium(IV) isopropoxide.

  16. Accumulation of electrophilic aldehydes during postovulatory aging of mouse oocytes causes reduced fertility, oxidative stress, and apoptosis.

    PubMed

    Lord, Tessa; Martin, Jacinta H; Aitken, R John

    2015-02-01

    With increasing periods of time following ovulation, the metaphase II (MII)-stage oocyte experiences overproduction of reactive oxygen species and elevated levels of lipid peroxidation that are implicitly linked with functional deficiencies acquired during postovulatory oocyte aging. We have demonstrated that the electrophilic aldehydes 4-hydroxynonenal (4HNE), malondialdehyde, and acrolein are by-products of nonenzymatic lipid peroxidation in the murine MII-stage oocyte, adducting to multiple proteins within the cell. The covalent modification of oocyte proteins by these aldehydes increased with extended periods of time postovulation; the mitochondrial protein succinate dehydrogenase (SDHA) was identified as a primary target for 4HNE adduction. Time- and dose-dependent studies revealed that exposure to elevated levels of electrophilic aldehydes causes mitochondrial reactive oxygen species production, lipid peroxidation, loss of mitochondrial membrane potential, and eventual apoptosis within the MII oocyte, presumably as a consequence of electron transport chain collapse following SDHA adduction. Additionally, we have determined that short-term exposure to low doses of 4HNE dramatically impairs the oocyte's ability to participate in fertilization and support embryonic development; however, this loss of functionality can be prevented by supplementation with the antioxidant penicillamine. In conclusion, this study has revealed that the accumulation of electrophilic aldehydes is linked to postovulatory oocyte aging, causing reduced fertility, oxidative stress, and apoptosis of this highly specialized cell. These data highlight the importance of timely fertilization of the mammalian oocyte postovulation and emphasize the potential advantages associated with antioxidant supplementation of oocyte culture medium in circumstances where reinsemination of oocytes may be desirable (i.e., rescue intracytoplasmic sperm injection), or where in vitro fertilization may be delayed

  17. WOR5, a Novel Tungsten-Containing Aldehyde Oxidoreductase from Pyrococcus furiosus with a Broad Substrate Specificity

    PubMed Central

    Bevers, Loes E.; Bol, Emile; Hagedoorn, Peter-Leon; Hagen, Wilfred R.

    2005-01-01

    WOR5 is the fifth and last member of the family of tungsten-containing oxidoreductases purified from the hyperthermophilic archaeon Pyrococcus furiosus. It is a homodimeric protein (subunit, 65 kDa) that contains one [4Fe-4S] cluster and one tungstobispterin cofactor per subunit. It has a broad substrate specificity with a high affinity for several substituted and nonsubstituted aliphatic and aromatic aldehydes with various chain lengths. The highest catalytic efficiency of WOR5 is found for the oxidation of hexanal (Vmax = 15.6 U/mg, Km = 0.18 mM at 60°C). Hexanal-incubated enzyme exhibits S = 1/2 electron paramagnetic resonance signals from [4Fe-4S]1+ (g values of 2.08, 1.93, and 1.87) and W5+ (g values of 1.977, 1.906, and 1.855). Cyclic voltammetry of ferredoxin and WOR5 on an activated glassy carbon electrode shows a catalytic wave upon addition of hexanal, suggesting that ferredoxin can be a physiological redox partner. The combination of WOR5, formaldehyde oxidoreductase, and aldehyde oxidoreductase forms an efficient catalyst for the oxidation of a broad range of aldehydes in P. furiosus. PMID:16199576

  18. Volatile Profile of Raw Lamb Meat Stored at 4 ± 1 °C: The Potential of Specific Aldehyde Ratios as Indicators of Lamb Meat Quality

    PubMed Central

    2018-01-01

    The objectives of the present study were: (a) to evaluate the aroma evolution of raw lamb packaged in multi-layer coating film and stored at 4 ± 1 °C, with respect to storage time and (b) to investigate whether specific aldehyde ratios could serve as markers of lamb meat freshness and degree of oxidation. Volatile compounds were determined using headspace solid phase microextraction coupled to gas chromatography/mass spectrometry. Results showed that the most dominant volatiles were 2,2,4,6,6-pentamethyl-heptane, hexanal, 1-octen-3-ol, 1-hexanol, carbon disulfide and p-cymene. Volatile compound content was increased during storage time. However, statistically significant differences were recorded only for hexanal, heptanal, and nonanal (p < 0.05). Additionally, the evolution of aldehydes during storage recorded a positive Pearson’s correlation (r) (p < 0.05), whereas hexanal to nonanal, heptanal to nonanal, octanal to nonanal ratios, along with the sum of aldehydes to nonanal ratio, were positively correlated (r = 0.83–1.00) with the degree of oxidation (mg malonic dialdehyde per kg of lamb meat). A perfect Pearson’s correlation (r = 1) was obtained for the ratio hexanal to nonanal. Therefore, this ratio is proposed as an indicator of lamb meat freshness and overall quality. PMID:29547528

  19. Checkpoint kinase 1 inhibition sensitises transformed cells to dihydroorotate dehydrogenase inhibition

    PubMed Central

    Arnould, Stéphanie; Rodier, Geneviève; Matar, Gisèle; Vincent, Charles; Pirot, Nelly; Delorme, Yoann; Berthet, Charlène; Buscail, Yoan; Noël, Jean Yohan; Lachambre, Simon; Jarlier, Marta; Bernex, Florence; Delpech, Hélène; Vidalain, Pierre Olivier; Janin, Yves L.; Theillet, Charles; Sardet, Claude

    2017-01-01

    Reduction in nucleotide pools through the inhibition of mitochondrial enzyme dihydroorotate dehydrogenase (DHODH) has been demonstrated to effectively reduce cancer cell proliferation and tumour growth. The current study sought to investigate whether this antiproliferative effect could be enhanced by combining Chk1 kinase inhibition. The pharmacological activity of DHODH inhibitor teriflunomide was more selective towards transformed mouse embryonic fibroblasts than their primary or immortalised counterparts, and this effect was amplified when cells were subsequently exposed to PF477736 Chk1 inhibitor. Flow cytometry analyses revealed substantial accumulations of cells in S and G2/M phases, followed by increased cytotoxicity which was characterised by caspase 3-dependent induction of cell death. Associating PF477736 with teriflunomide also significantly sensitised SUM159 and HCC1937 human triple negative breast cancer cell lines to dihydroorotate dehydrogenase inhibition. The main characteristic of this effect was the sustained accumulation of teriflunomide-induced DNA damage as cells displayed increased phospho serine 139 H2AX (γH2AX) levels and concentration-dependent phosphorylation of Chk1 on serine 345 upon exposure to the combination as compared with either inhibitor alone. Importantly a similar significant increase in cell death was observed upon dual siRNA mediated depletion of Chk1 and DHODH in both murine and human cancer cell models. Altogether these results suggest that combining DHODH and Chk1 inhibitions may be a strategy worth considering as a potential alternative to conventional chemotherapies. PMID:29221122

  20. Campholenic aldehyde ozonolysis: a mechanism leading to specific biogenic secondary organic aerosol constituents

    NASA Astrophysics Data System (ADS)

    Kahnt, A.; Iinuma, Y.; Mutzel, A.; Böge, O.; Claeys, M.; Herrmann, H.

    2014-01-01

    In the present study, campholenic aldehyde ozonolysis was performed to investigate pathways leading to specific biogenic secondary organic aerosol (SOA) marker compounds. Campholenic aldehyde, a known α-pinene oxidation product, is suggested to be a key intermediate in the formation of terpenylic acid upon α-pinene ozonolysis. It was reacted with ozone in the presence and absence of an OH radical scavenger, leading to SOA formation with a yield of 0.75 and 0.8, respectively. The resulting oxidation products in the gas and particle phases were investigated employing a denuder/filter sampling combination. Gas-phase oxidation products bearing a carbonyl group, which were collected by the denuder, were derivatised by 2,4-dinitrophenylhydrazine (DNPH) followed by liquid chromatography/negative ion electrospray ionisation time-of-flight mass spectrometry analysis and were compared to the gas-phase compounds detected by online proton-transfer-reaction mass spectrometry. Particle-phase products were also analysed, directly or after DNPH derivatisation, to derive information about specific compounds leading to SOA formation. Among the detected compounds, the aldehydic precursor of terpenylic acid was identified and its presence was confirmed in ambient aerosol samples from the DNPH derivatisation, accurate mass data, and additional mass spectrometry (MS2 and MS3 fragmentation studies). Furthermore, the present investigation sheds light on a reaction pathway leading to the formation of terpenylic acid, involving α-pinene, α-pinene oxide, campholenic aldehyde, and terpenylic aldehyde. Additionally, the formation of diaterpenylic acid acetate could be connected to campholenic aldehyde oxidation. The present study also provides insights into the source of other highly functionalised oxidation products (e.g. m / z 201, C9H14O5 and m / z 215, C10H16O5), which have been observed in ambient aerosol samples and smog chamber-generated monoterpene SOA. The m / z 201 and 215

  1. Oxidative bioactivation of abacavir in subcellular fractions of human antigen presenting cells.

    PubMed

    Bell, Catherine C; Santoyo Castelazo, Anahi; Yang, Emma L; Maggs, James L; Jenkins, Rosalind E; Tugwood, Jonathan; O'Neill, Paul M; Naisbitt, Dean J; Park, B Kevin

    2013-07-15

    Human exposure to abacavir, a primary alcohol antiretroviral, is associated with the development of immunological drug reactions in individuals carrying the HLA risk allele B*57:01. Interaction of abacavir with antigen presenting cells results in cell activation through an Hsp70-mediated Toll-like receptor pathway and the provision of T-cell antigenic determinants. Abacavir's electrophilic aldehyde metabolites are potential precursors of neoantigens. Herein, we have used mass spectrometry to study the oxidative metabolism of abacavir in EBV-transformed human B-cells. RNA and protein were isolated from the cells and subjected to transcriptomic and mass spectrometric analyses to identify the redox enzymes expressed. Low levels of isomeric abacavir carboxylic acids were detected in subcellular fractions of EBV-transformed human B-cells incubated with abacavir. Metabolite formation was time-dependent but was not reduced by an inhibitor of Class I alcohol dehydrogenases. Relatively high levels of mRNA were detected for several redox enzymes, including alcohol dehydrogenase 5 (Class III), aldehyde dehydrogenases (ALDH3A2, ALDH6A1, and ALDH9A1), CYP1B1, CYP2R1, CYP7B1, and hydroxysteroid dehydrogenase 10. Over 2600 proteins were identified by mass spectrometry. More than 1000 of these proteins exhibited catalytic activity, and 80 were oxido-reductases. This is the first proteomic inventory of enzymes in antigen presenting cells. However, neither of the hepatic alcohol dehydrogenases of Class I which metabolize abacavir in vitro was expressed at the protein level. Nevertheless the metabolic production of abacavir carboxylic acids by B-cell fractions implies abacavir-treated immune cells might be exposed to the drug's protein-reactive aldehyde metabolites in vivo.

  2. Disrupting androgen production of Leydig cells by resveratrol via direct inhibition of human and rat 3β-hydroxysteroid dehydrogenase.

    PubMed

    Li, Ling; Chen, Xiaomin; Zhu, Qiqi; Chen, Dongxin; Guo, Jingjing; Yao, Wenwen; Dong, Yaoyao; Wei, Jia; Lian, Qingquan; Ge, Ren-Shan; Yuan, Bo

    2014-04-07

    Resveratrol is a polyphenol produced by several plants. It has been demonstrated that it has anti-inflammatory, antitumor, and anti-diabetic effects in animal models. However, its side effects are generally unclear. In the present study, we reported that resveratrol inhibited luteinizing hormone-stimulated androgen production in rat immature Leydig cells. Further analysis demonstrated that it was a competitive inhibitor of rat and human 3β-hydroxysteroid dehydrogenase with IC₆₀ values of 3.87 ± 0.06 and 8.48 ± 0.04 μM, respectively. The inhibition on 3β-hydroxysteroid dehydrogenase was specific since it did not inhibit another hydroxysteroid dehydrogenase 17β-hydroxysteroid dehydrogenase 3 at the highest concentration (100 μM) tested. In conclusion, resveratrol potentially interferes with androgen biosynthesis of rat Leydig cells. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. GDH3 encodes a glutamate dehydrogenase isozyme, a previously unrecognized route for glutamate biosynthesis in Saccharomyces cerevisiae.

    PubMed Central

    Avendaño, A; Deluna, A; Olivera, H; Valenzuela, L; Gonzalez, A

    1997-01-01

    It has been considered that the yeast Saccharomyces cerevisiae, like many other microorganisms, synthesizes glutamate through the action of NADP+-glutamate dehydrogenase (NADP+-GDH), encoded by GDH1, or through the combined action of glutamine synthetase and glutamate synthase (GOGAT), encoded by GLN1 and GLT1, respectively. A double mutant of S. cerevisiae lacking NADP+-GDH and GOGAT activities was constructed. This strain was able to grow on ammonium as the sole nitrogen source and thus to synthesize glutamate through an alternative pathway. A computer search for similarities between the GDH1 nucleotide sequence and the complete yeast genome was carried out. In addition to identifying its cognate sequence at chromosome XIV, the search found that GDH1 showed high identity with a previously recognized open reading frame (GDH3) of chromosome I. Triple mutants impaired in GDH1, GLT1, and GDH3 were obtained. These were strict glutamate auxotrophs. Our results indicate that GDH3 plays a significant physiological role, providing glutamate when GDH1 and GLT1 are impaired. This is the first example of a microorganism possessing three pathways for glutamate biosynthesis. PMID:9287019

  4. Interaction of cytoplasmic dehydrogenases: quantitation of pathways of ethanol metabolism.

    PubMed

    Vind, C; Grunnet, N

    1983-01-01

    The interaction between xylitol, alcohol and lactate dehydrogenase has been studied in hepatocytes from rats by applying specifically tritiated substrates. A simple model, describing the metabolic fate of tritium from [2-3H] xylitol and (1R) [1-3H]ethanol is presented. The model allows calculation of the specific radioactivity of free, cytosolic NADH, based on transfer of tritium to lactate, glucose and water. From the initial labelling rate of lactate and the specific radioactivity of cytosolic NADH, we have determined the reversible flow through the lactate dehydrogenase catalyzed reaction to 1-5 mumol/min . g wet wt. The results suggest that xylitol, alcohol and lactate dehydrogenase share the same pool of NAD(H) in the cytoplasma. This finding allows estimation of the ethanol oxidation rate by the non-alcohol dehydrogenase pathways from the relative yield of tritium in water and glucose. The calculations are based on a comparison of the fate of the 1-pro-R hydrogen of ethanol and the hydrogen bound to carbon 2 of xylitol or carbon 2 of lactate under identical conditions.

  5. Yeast surface display of dehydrogenases in microbial fuel-cells.

    PubMed

    Gal, Idan; Schlesinger, Orr; Amir, Liron; Alfonta, Lital

    2016-12-01

    Two dehydrogenases, cellobiose dehydrogenase from Corynascus thermophilus and pyranose dehydrogenase from Agaricus meleagris, were displayed for the first time on the surface of Saccharomyces cerevisiae using the yeast surface display system. Surface displayed dehydrogenases were used in a microbial fuel cell and generated high power outputs. Surface displayed cellobiose dehydrogenase has demonstrated a midpoint potential of -28mV (vs. Ag/AgCl) at pH=6.5 and was used in a mediator-less anode compartment of a microbial fuel cell producing a power output of 3.3μWcm(-2) using lactose as fuel. Surface-displayed pyranose dehydrogenase was used in a microbial fuel cell and generated high power outputs using different substrates, the highest power output that was achieved was 3.9μWcm(-2) using d-xylose. These results demonstrate that surface displayed cellobiose dehydrogenase and pyranose dehydrogenase may successfully be used in microbial bioelectrochemical systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. CYP3A-Mediated Generation of Aldehyde and Hydrazine in Atazanavir MetabolismS⃞

    PubMed Central

    Li, Feng; Lu, Jie; Wang, Laiyou

    2011-01-01

    Atazanavir (ATV) is an antiretroviral drug of the protease inhibitor class. Multiple adverse effects of ATV have been reported in clinical practice, such as jaundice, nausea, abdominal pain, and headache. The exact mechanisms of ATV-related adverse effects are unknown. It is generally accepted that a predominant pathway of drug-induced toxicity is through the generation of reactive metabolites. Our current study was designed to explore reactive metabolites of ATV. We used a metabolomic approach to profile ATV metabolism in mice and human liver microsomes. We identified 5 known and 13 novel ATV metabolites. Three potential reactive metabolites were detected and characterized for the first time: one aromatic aldehyde, one α-hydroxyaldehyde, and one hydrazine. These potential reactive metabolites were primarily generated by CYP3A. Our results provide a clue for studies on ATV-related adverse effects from the aspect of metabolic activation. Further studies are suggested to illustrate the impact of these potential reactive metabolites on ATV-related adverse effects. PMID:21148252

  7. A modified Girard derivatizing reagent for universal profiling and trace analysis of aldehydes and ketones by electrospray ionization tandem mass spectrometry.

    PubMed

    Johnson, David W

    2007-01-01

    4-Hydrazino-N,N,N-trimethyl-4-oxobutanaminium iodide (HTMOB) is a modified Girard derivatizing reagent synthesized to improve the sensitivity of analysis of aldehydes and ketones with electrospray ionization tandem mass spectrometry. Compared with Girard T reagent the measured signal intensity increase is between 3.3 times (succinylacetone) and 7.0 times (17-hydroxyprogesterone). HTMOB is a universal profiling reagent for aldehydes and ketones. A neutral loss of 59 Da scan detects all aldehydes and ketones from acetone to corticosteroids. Applications described include the profiling of ketones, ketoacids and ketodiacids in the urine of children with ketosis and the profiling of long-chain aldehydes incorporated in plasma plasmalogens. Copyright (c) 2007 John Wiley & Sons, Ltd.

  8. Formation and Accumulation of Acetaldehyde and Strecker Aldehydes during Red Wine Oxidation.

    PubMed

    Bueno, Mónica; Marrufo-Curtido, Almudena; Carrascón, Vanesa; Fernández-Zurbano, Purificación; Escudero, Ana; Ferreira, Vicente

    2018-01-01

    The main aim of the present work is to study the accumulation of acetaldehyde and Strecker aldehydes (isobutyraldehyde, 2-methylbutanal, isovaleraldehyde, methional, phenylacetaldehyde) during the oxidation of red wines, and to relate the patterns of accumulation to the wine chemical composition. For that, eight different wines, extensively chemically characterized, were subjected at 25°C to three different controlled O 2 exposure conditions: low (10 mg L -1 ) and medium or high (the stoichiometrically required amount to oxidize all wine total SO 2 plus 18 or 32 mg L -1 , respectively). Levels of volatile aldehydes and carbonyls were then determined and processed by different statistical techniques. Results showed that young wines (<2 years-old bottled wines) hardly accumulate any acetaldehyde regardless of the O 2 consumed. In contrast, aged wines (>3 years-old bottled wines) accumulated acetaldehyde while their content in SO 2 was not null, and the aged wine containing lowest polyphenols accumulated it throughout the whole process. Models suggest that the ability of a wine to accumulate acetaldehyde is positively related to its content in combined SO 2 , in epigallocatechin and to the mean degree of polymerization, and negatively to its content in Aldehyde Reactive Polyphenols (ARPs) which, attending to our models, are anthocyanins and small tannins. The accumulation of Strecker aldehydes is directly proportional to the wine content in the amino acid precursor, being the proportionality factor much higher for aged wines, except for phenylacetaldehyde, for which the opposite pattern was observed. Models suggest that non-aromatic Strecker aldehydes share with acetaldehyde a strong affinity toward ARPs and that the specific pattern of phenylacetaldehyde is likely due to a much reduced reactivity toward ARPs, to the possibility that diacetyl induces Strecker degradation of phenyl alanine and to the potential higher reactivity of this amino acid to some quinones

  9. Formation and Accumulation of Acetaldehyde and Strecker Aldehydes during Red Wine Oxidation

    PubMed Central

    Bueno, Mónica; Marrufo-Curtido, Almudena; Carrascón, Vanesa; Fernández-Zurbano, Purificación; Escudero, Ana; Ferreira, Vicente

    2018-01-01

    The main aim of the present work is to study the accumulation of acetaldehyde and Strecker aldehydes (isobutyraldehyde, 2-methylbutanal, isovaleraldehyde, methional, phenylacetaldehyde) during the oxidation of red wines, and to relate the patterns of accumulation to the wine chemical composition. For that, eight different wines, extensively chemically characterized, were subjected at 25°C to three different controlled O2 exposure conditions: low (10 mg L−1) and medium or high (the stoichiometrically required amount to oxidize all wine total SO2 plus 18 or 32 mg L−1, respectively). Levels of volatile aldehydes and carbonyls were then determined and processed by different statistical techniques. Results showed that young wines (<2 years-old bottled wines) hardly accumulate any acetaldehyde regardless of the O2 consumed. In contrast, aged wines (>3 years-old bottled wines) accumulated acetaldehyde while their content in SO2 was not null, and the aged wine containing lowest polyphenols accumulated it throughout the whole process. Models suggest that the ability of a wine to accumulate acetaldehyde is positively related to its content in combined SO2, in epigallocatechin and to the mean degree of polymerization, and negatively to its content in Aldehyde Reactive Polyphenols (ARPs) which, attending to our models, are anthocyanins and small tannins. The accumulation of Strecker aldehydes is directly proportional to the wine content in the amino acid precursor, being the proportionality factor much higher for aged wines, except for phenylacetaldehyde, for which the opposite pattern was observed. Models suggest that non-aromatic Strecker aldehydes share with acetaldehyde a strong affinity toward ARPs and that the specific pattern of phenylacetaldehyde is likely due to a much reduced reactivity toward ARPs, to the possibility that diacetyl induces Strecker degradation of phenyl alanine and to the potential higher reactivity of this amino acid to some quinones derived

  10. Formation and accumulation of acetaldehyde and Strecker aldehydes during red wine oxidation

    NASA Astrophysics Data System (ADS)

    Bueno, Mónica; Marrufo-Curtido, Almudena; Carrascón, Vanesa; Fernández-Zurbano, Purificación; Escudero, Ana; Ferreira, Vicente

    2018-02-01

    The main aim of the present work is to study the accumulation of acetaldehyde and Strecker aldehydes (isobutyraldehyde, 2-methylbutanal, isovaleraldehyde, methional, phenylacetaldehyde) during the oxidation of red wines, and to relate the patterns of accumulation to the wine chemical composition. For that, eight different wines, extensively chemically characterized, were subjected at 25°C to three different controlled O2 exposure conditions: low (10 mg L-1) and medium or high (the stoichiometrically required amount to oxidize all wine total SO2 plus 18 or 32 mg L-1, respectively). Levels of volatile aldehydes and carbonyls were then determined and processed by different statistical techniques. Results showed that young wines (<2 years-old bottled wines) hardly accumulate any acetaldehyde regardless of the O2 consumed. In contrast, aged wines (>3 years-old bottled wines) accumulated acetaldehyde while their content in SO2 was not null, and the aged wine containing lowest polyphenols accumulated it throughout the whole process. Models suggest that the ability of a wine to accumulate acetaldehyde is positively related to its content in combined SO2, in epigallocatechin and to the mean degree of polymerization, and negatively to its content in Aldehyde Reactive Polyphenols (ARPs) which, attending to our models, are anthocyanins and small tannins. The accumulation of Strecker aldehydes is directly proportional to the wine content in the amino acid precursor, being the proportionality factor much higher for aged wines, except for phenylacetaldehyde, for which the opposite pattern was observed. Models suggest that non-aromatic Strecker aldehydes share with acetaldehyde a strong affinity towards ARPs and that the specific pattern of phenylacetaldehyde is likely due to a much reduced reactivity towards ARPs, to the possibility that diacetyl induces Strecker degradation of phenyl alanine and to the potential higher reactivity of this amino acid to some quinones derived from

  11. Regulation of NAD+-linked isocitrate dehydrogenase and 2-oxoglutarate dehydrogenase by Ca2+ ions within toluene-permeabilized rat heart mitochondria. Interactions with regulation by adenine nucleotides and NADH/NAD+ ratios.

    PubMed Central

    Rutter, G A; Denton, R M

    1988-01-01

    1. Toluene-permeabilized rat heart mitochondria have been used to study the regulation of NAD+-linked isocitrate dehydrogenase and 2-oxoglutarate dehydrogenase by Ca2+, adenine and nicotinamide nucleotides, and to compare the properties of the enzymes in situ, with those in mitochondrial extracts. 2. Although K0.5 values (concn. giving half-maximal effect) for Ca2+ of 2-oxoglutarate dehydrogenase were around 1 microM under all conditions, corresponding values for NAD+-linked isocitrate dehydrogenase were in the range 5-43 microM. 3. For both enzymes, K0.5 values for Ca2+ observed in the presence of ATP were 3-10-fold higher than those in the presence of ADP, with values increasing over the ADP/ATP range 0.0-1.0. 4. 2-Oxoglutarate dehydrogenase was less sensitive to inhibition by NADH when assayed in permeabilized mitochondria than in mitochondrial extracts. Similarly, the Km of NAD+-linked isocitrate dehydrogenase for threo-Ds-isocitrate was lower in permeabilized mitochondria than in extracts under all the conditions investigated. 5. It is concluded that in the intact heart Ca2+ activation of NAD+-linked isocitrate dehydrogenase may not necessarily occur in parallel with that of the other mitochondrial Ca2+-sensitive enzymes, 2-oxoglutarate dehydrogenase and the pyruvate dehydrogenase system. PMID:3421900

  12. Process for producing furan from furfural aldehyde

    DOEpatents

    Diebold, James P.; Evans, Robert J.

    1988-01-01

    A process of producing furan and derivatives thereof is disclosed. The process includes generating furfural aldehyde vapors and then passing those vapors over a zeolite catalyst at a temperature and for a residence time effective to decarbonylate the furfural aldehydes to form furans and derivatives thereof. The resultant furan vapors and derivatives are then separated. In a preferred form, the furfural aldehyde vapors are generated during the process of converting biomass materials to liquid and gaseous fuels.

  13. Process for producing furan from furfural aldehyde

    DOEpatents

    Diebold, J.P.; Evans, R.J.

    1987-04-06

    A process of producing furan and derivatives thereof as disclosed. The process includes generating furfural aldehyde vapors and then passing those vapors over a zeolite catalyst at a temperature and for a residence time effective to decarbonylate the furfural aldehydes to form furans and derivatives thereof. The resultant furan vapors and derivatives are then separated. In a preferred form, the furfural aldehyde vapors are generated during the process of converting biomass materials to liquid and gaseous fuels.

  14. Development of a novel polystyrene/metal-organic framework-199 electrospun nanofiber adsorbent for thin film microextraction of aldehydes in human urine.

    PubMed

    Liu, Feilong; Xu, Hui

    2017-01-01

    In this work, electrospun polystyrene/metal-organic frameworks-199 (PS/MOF-199) nanofiber film was synthesized and investigated as a novel adsorbent for thin film microextraction (TFME) of aldehydes in human urine. Some properties of the prepared PS/MOF-199 nanofiber film, including morphology, structure, wettability, solvent stability and extraction performance were studied systematically. Porous fibrous structure, large surface area, good stability, strong hydrophobicity and excellent extraction efficiency were obtained for the film. Based on the PS/MOF-199 film, a thin film microextraction-high performance liquid chromatography (TFME-HPLC) method was developed, and the experimental parameters that affected the extraction and desorption were optimized. Under the optimal conditions, the limits of detection (LODs) were in the range of 4.2-17.3nmolL -1 for the analysis of six aldehydes. Good linearity was achieved with correlation coefficients (R 2 ) being lager than 0.9943. Satisfactory recovery (82-112%) and acceptable reproducibility (relative standard deviation: 2.1-13.3%) were also obtained for the method. The developed TFME-HPLC method has been successfully applied to the analysis of aldehyde metabolites in the urine samples of lung cancer patients and healthy people. The method possesses the advantages of simplicity, rapidity, cost-effective, sensitivity and non-invasion, it provides an alternative tool for the determination of aldehydes in complex sample matrices. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Heme binding properties of glyceraldehyde-3-phosphate dehydrogenase.

    PubMed

    Hannibal, Luciana; Collins, Daniel; Brassard, Julie; Chakravarti, Ritu; Vempati, Rajesh; Dorlet, Pierre; Santolini, Jérôme; Dawson, John H; Stuehr, Dennis J

    2012-10-30

    Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a glycolytic enzyme that also functions in transcriptional regulation, oxidative stress, vesicular trafficking, and apoptosis. Because GAPDH is required for the insertion of cellular heme into inducible nitric oxide synthase [Chakravarti, R., et al. (2010) Proc. Natl. Acad. Sci. U.S.A. 107, 18004-18009], we extensively characterized the heme binding properties of GAPDH. Substoichiometric amounts of ferric heme bound to GAPDH (one heme per GAPDH tetramer) to form a low-spin complex with UV-visible maxima at 362, 418, and 537 nm and when reduced to ferrous gave maxima at 424, 527, and 559 nm. Ferric heme association and dissociation rate constants at 10 °C were as follows: k(on) = 17800 M(-1) s(-1), k(off1) = 7.0 × 10(-3) s(-1), and k(off2) = 3.3 × 10(-4) s(-1) (giving approximate affinities of 19-390 nM). Ferrous heme bound more poorly to GAPDH and dissociated with a k(off) of 4.2 × 10(-3) s(-1). Magnetic circular dichroism, resonance Raman, and electron paramagnetic resonance spectroscopic data on the ferric, ferrous, and ferrous-CO complexes of GAPDH showed that the heme is bis-ligated with His as the proximal ligand. The distal ligand in the ferric complex was not displaced by CN(-) or N(3)(-) but in the ferrous complex could be displaced by CO at a rate of 1.75 s(-1) (for >0.2 mM CO). Studies with heme analogues revealed selectivity toward the coordinating metal and porphyrin ring structure. The GAPDH-heme complex was isolated from bacteria induced to express rabbit GAPDH in the presence of δ-aminolevulinic acid. Our finding of heme binding to GAPDH expands the protein's potential roles. The strength, selectivity, reversibility, and redox sensitivity of heme binding to GAPDH are consistent with it performing heme sensing or heme chaperone-like functions in cells.

  16. Structure and mechanism of action of the hydroxy-aryl-aldehyde class of IRE1 endoribonuclease inhibitors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sanches, Mario; Duffy, Nicole M.; Talukdar, Manisha

    2014-10-24

    Endoplasmic reticulum (ER) stress activates the unfolded protein response and its dysfunction is linked to multiple diseases. The stress transducer IRE1α is a transmembrane kinase endoribonuclease (RNase) that cleaves mRNA substrates to re-establish ER homeostasis. Aromatic ring systems containing hydroxy–aldehyde moieties, termed hydroxy–aryl–aldehydes (HAA), selectively inhibit IRE1α RNase and thus represent a novel chemical series for therapeutic development. We solved crystal structures of murine IRE1α in complex with three HAA inhibitors. HAA inhibitors engage a shallow pocket at the RNase-active site through pi-stacking interactions with His910 and Phe889, an essential Schiff base with Lys907 and a hydrogen bond with Tyr892.more » Structure–activity studies and mutational analysis of contact residues define the optimal chemical space of inhibitors and validate the inhibitor-binding site. These studies lay the foundation for understanding both the biochemical and cellular functions of IRE1α using small molecule inhibitors and suggest new avenues for inhibitor design.« less

  17. Effects of biogenic aldehydes and aldehyde dehydrogenase inhibitors on rat brain tryptophan hydroxylase activity in vitro.

    PubMed

    Nilsson, G E; Tottmar, O

    1987-04-21

    The effect of indole-3-acetaldehyde, 5-hydroxyindole-3-acetaldehyde, disulfiram, diethyldithiocarbamate, coprine, and 1-amino-cyclopropanol on tryptophan hydroxylase activity was studied in vitro using high performance liquid chromatography with electro-chemical detection. With the analytical method developed, 5-hydroxytryptophan, serotonin, and 5-hydroxyindole-3-acetic acid could be measured simultaneously. Indole-3-acetaldehyde (12-1200 microM) was found to cause a 6-33% inhibition of the enzyme. Dependent upon the nature of the sulfhydryl- or reducing-agent (dithiotreitol, glutathione, or ascorbate) present in the incubates, the degree of inhibition by disulfiram varied, probably due to the formation of various mixed disulfides. Also the presence of diethyldithiocarbamate (160-1600 microM) was found to inhibit tryptophan hydroxylase (28-91%), while 5-hydroxyindole-3-acetaldehyde, coprine, or 1-aminocyclopropanol appeared to have no effect on the enzyme activity.

  18. Microsphere coated substrate containing reactive aldehyde groups

    NASA Technical Reports Server (NTRS)

    Yen, Richard C. K. (Inventor); Rembaum, Alan (Inventor)

    1984-01-01

    A synthetic organic resin is coated with a continuous layer of contiguous, tangential, individual microspheres having a uniform diameter preferably between 100 Angstroms and 2000 Angstroms. The microspheres are an addition polymerized polymer of an unsaturated aldehyde containing 4 to 20 carbon atoms and are covalently bonded to the substrate by means of high energy radiation grafting. The microspheres contain reactive aldehyde groups and can form conjugates with proteins such as enzymes or other aldehyde reactive materials.

  19. Et3B-mediated radical-polar crossover reaction for single-step coupling of O,Te-acetal, α,β-unsaturated ketones, and aldehydes/ketones.

    PubMed

    Kamimura, Daigo; Urabe, Daisuke; Nagatomo, Masanori; Inoue, Masayuki

    2013-10-04

    Et3B-mediated three-component coupling reactions between O,Te-acetal, α,β-unsaturated ketones, and aldehydes/ketones were developed. Et3B promoted the generation of the potently reactive bridgehead radical from the O,Te-acetal of the trioxaadamantane structure and converted the α-carbonyl radical of the resultant two-component adduct to the boron enolate, which then underwent a stereoselective aldol reaction with the aldehyde/ketone. This powerful, yet mild, radical-polar crossover reaction efficiently connected the hindered linkages between the three units and selectively introduced three new stereocenters.

  20. Manganese catalyzed reductive amination of aldehydes using hydrogen as a reductant.

    PubMed

    Wei, Duo; Bruneau-Voisine, Antoine; Valyaev, Dmitry A; Lugan, Noël; Sortais, Jean-Baptiste

    2018-04-24

    A one-pot two-step procedure was developed for the alkylation of amines via reductive amination of aldehydes using molecular dihydrogen as a reductant in the presence of a manganese pyridinyl-phosphine complex as a pre-catalyst. After the initial condensation step, the reduction of imines formed in situ is performed under mild conditions (50-100 °C) with 2 mol% of catalyst and 5 mol% of tBuOK under 50 bar of hydrogen. Excellent yields (>90%) were obtained for a large combination of aldehydes and amines (40 examples), including aliphatic aldehydes and amino-alcohols.