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Sample records for aldehyde dehydrogenase

  1. Contribution of aldehyde oxidase, xanthine oxidase, and aldehyde dehydrogenase on the oxidation of aromatic aldehydes.

    Science.gov (United States)

    Panoutsopoulos, Georgios I; Kouretas, Demetrios; Beedham, Christine

    2004-10-01

    Aliphatic aldehydes have a high affinity toward aldehyde dehydrogenase activity but are relatively poor substrates of aldehyde oxidase and xanthine oxidase. In addition, the oxidation of xenobiotic-derived aromatic aldehydes by the latter enzymes has not been studied to any great extent. The present investigation compares the relative contribution of aldehyde dehydrogenase, aldehyde oxidase, and xanthine oxidase activities in the oxidation of substituted benzaldehydes in separate preparations. The incubation of vanillin, isovanillin, and protocatechuic aldehyde with either guinea pig liver aldehyde oxidase, bovine milk xanthine oxidase, or guinea pig liver aldehyde dehydrogenase demonstrated that the three aldehyde oxidizing enzymes had a complementary substrate specificity. Incubations were also performed with specific inhibitors of each enzyme (isovanillin for aldehyde oxidase, allopurinol for xanthine oxidase, and disulfiram for aldehyde dehydrogenase) to determine the relative contribution of each enzyme in the oxidation of these aldehydes. Under these conditions, vanillin was rapidly oxidized by aldehyde oxidase, isovanillin was predominantly metabolized by aldehyde dehydrogenase activity, and protocatechuic aldehyde was slowly oxidized, possibly by all three enzymes. Thus, aldehyde oxidase activity may be a significant factor in the oxidation of aromatic aldehydes generated from amines and alkyl benzenes during drug metabolism. In addition, this enzyme may also have a role in the catabolism of biogenic amines such as dopamine and noradrenaline where 3-methoxyphenylacetic acids are major metabolites.

  2. Aldehyde dehydrogenases and cell proliferation.

    Science.gov (United States)

    Muzio, G; Maggiora, M; Paiuzzi, E; Oraldi, M; Canuto, R A

    2012-02-15

    Aldehyde dehydrogenases (ALDHs) oxidize aldehydes to the corresponding carboxylic acids using either NAD or NADP as a coenzyme. Aldehydes are highly reactive aliphatic or aromatic molecules that play an important role in numerous physiological, pathological, and pharmacological processes. ALDHs have been discovered in practically all organisms and there are multiple isoforms, with multiple subcellular localizations. More than 160 ALDH cDNAs or genes have been isolated and sequenced to date from various sources, including bacteria, yeast, fungi, plants, and animals. The eukaryote ALDH genes can be subdivided into several families; the human genome contains 19 known ALDH genes, as well as many pseudogenes. Noteworthy is the fact that elevated activity of various ALDHs, namely ALDH1A2, ALDH1A3, ALDH1A7, ALDH2*2, ALDH3A1, ALDH4A1, ALDH5A1, ALDH6, and ALDH9A1, has been observed in normal and cancer stem cells. Consequently, ALDHs not only may be considered markers of these cells, but also may well play a functional role in terms of self-protection, differentiation, and/or expansion of stem cell populations. The ALDH3 family includes enzymes able to oxidize medium-chain aliphatic and aromatic aldehydes, such as peroxidic and fatty aldehydes. Moreover, these enzymes also have noncatalytic functions, including antioxidant functions and some structural roles. The gene of the cytosolic form, ALDH3A1, is localized on chromosome 17 in human beings and on the 11th and 10th chromosome in the mouse and rat, respectively. ALDH3A1 belongs to the phase II group of drug-metabolizing enzymes and is highly expressed in the stomach, lung, keratinocytes, and cornea, but poorly, if at all, in normal liver. Cytosolic ALDH3 is induced by polycyclic aromatic hydrocarbons or chlorinated compounds, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin, in rat liver cells and increases during carcinogenesis. It has been observed that this increased activity is directly correlated with the degree of

  3. Aldehyde dehydrogenase protein superfamily in maize.

    Science.gov (United States)

    Zhou, Mei-Liang; Zhang, Qian; Zhou, Ming; Qi, Lei-Peng; Yang, Xiong-Bang; Zhang, Kai-Xuan; Pang, Jun-Feng; Zhu, Xue-Mei; Shao, Ji-Rong; Tang, Yi-Xiong; Wu, Yan-Min

    2012-11-01

    Maize (Zea mays ssp. mays L.) is an important model organism for fundamental research in the agro-biotechnology field. Aldehydes were generated in response to a suite of environmental stresses that perturb metabolism including salinity, dehydration, desiccation, and cold and heat shock. Many biologically important aldehydes are metabolized by the superfamily of NAD(P)(+)-dependent aldehyde dehydrogenases. Here, starting from the database of Z. mays, we identified 28 aldehyde dehydrogenase (ALDH) genes and 48 transcripts by the in silico cloning method using the ALDH-conserved domain amino acid sequence of Arabidopsis and rice as a probe. Phylogenetic analysis shows that all 28 members of the ALDH gene families were classified to ten distinct subfamilies. Microarray data and quantitative real-time PCR analysis reveal that ZmALDH9, ZmALDH13, and ZmALDH17 genes involve the function of drought stress, acid tolerance, and pathogens infection. These results suggested that these three ZmALDH genes might be potentially useful in maize genetic improvement.

  4. Detection of aldehyde dehydrogenase activity in human corneal extracts

    NARCIS (Netherlands)

    Gondhowiardjo, T. D.; van Haeringen, N. J.; Hoekzema, R.; Pels, L.; Kijlstra, A.

    1991-01-01

    The major soluble protein in bovine corneal epithelial extracts is a 54 kD protein (BCP 54) which has recently been identified as the corneal aldehyde dehydrogenase. Although ALDH activity has been reported in human corneal extracts it was not yet clear whether this was identical with the 54 kD

  5. Prognostic values of aldehyde dehydrogenase 1 isoenzymes in ovarian cancer

    OpenAIRE

    Ma, Yu-mei; Zhao, Shan

    2016-01-01

    Yu-mei Ma,1 Shan Zhao2 1Department of Pathology, 2Department of Cancer Second Division, The Second Hospital of Hebei Medical University, Shijiazhuang City, People’s Republic of China Abstract: Aldehyde dehydrogenase 1 (ALDH1) activity has been used as a functional stem cell marker to isolate cancer stem cells in different cancer types, including ovarian cancer. However, which ALDH1’s isoenzymes are contributing to ALDH1 activity in ovarian cancer remains elusive. In addi...

  6. Effects of herbal infusions, tea and carbonated beverages on alcohol dehydrogenase and aldehyde dehydrogenase activity.

    Science.gov (United States)

    Li, Sha; Gan, Li-Qin; Li, Shu-Ke; Zheng, Jie-Cong; Xu, Dong-Ping; Li, Hua-Bin

    2014-01-01

    Various alcoholic beverages containing different concentrations of ethanol are widely consumed, and excessive alcohol consumption may result in serious health problems. The consumption of alcoholic beverages is often accompanied by non-alcoholic beverages, such as herbal infusions, tea and carbonated beverages to relieve drunk symptoms. The aim of this study was to supply new information on the effects of these beverages on alcohol metabolism for nutritionists and the general public, in order to reduce problems associated with excessive alcohol consumption. The effects of 57 kinds of herbal infusions, tea and carbonated beverages on alcohol dehydrogenase and aldehyde dehydrogenase activity were evaluated. Generally, the effects of these beverages on alcohol dehydrogenase and aldehyde dehydrogenase activity are very different. The results suggested that some beverages should not be drank after excessive alcohol consumption, and several beverages may be potential dietary supplements for the prevention and treatment of problems related to excessive alcohol consumption.

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

    Science.gov (United States)

    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

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

    Czech Academy of Sciences Publication Activity Database

    Končitíková, R.; Vigouroux, A.; Kopečná, M.; Andree, T.; Bartoš, Jan; Šebela, M.; Moréra, S.; Kopečný, D.

    2015-01-01

    Roč. 468, Part: 1 (2015), s. 109-123 ISSN 0264-6021 R&D Projects: GA ČR GA15-22322S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : aldehyde dehydrogenase 2 (ALDH2) * aldehyde dehydrogenase 7 (ALDH7) * benzaldehyde Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.562, year: 2015

  9. Targeting aldehyde dehydrogenase: a potential approach for cell labeling

    Energy Technology Data Exchange (ETDEWEB)

    Vaidyanathan, Ganesan [Department of Radiology, Duke University Medical Center, Box 3808, Durham, NC 27710 (United States)], E-mail: ganesan.v@duke.edu; Song, Haijing; Affleck, Donna; McDougald, Darryl L. [Department of Radiology, Duke University Medical Center, Box 3808, Durham, NC 27710 (United States); Storms, Robert W. [Division of Cellular Therapy, Department of Medicine, Duke University Medical Center, Durham, NC 27710 (United States); Zalutsky, Michael R.; Chin, Bennett B. [Department of Radiology, Duke University Medical Center, Box 3808, Durham, NC 27710 (United States)

    2009-11-15

    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 radioiodinated 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 of [{sup 125}I]FMIC and [{sup 125}I]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.

  10. Targeting aldehyde dehydrogenase: a potential approach for cell labeling

    International Nuclear Information System (INIS)

    Vaidyanathan, Ganesan; Song, Haijing; Affleck, Donna; McDougald, Darryl L.; Storms, Robert W.; Zalutsky, 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 radioiodinated 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 of [ 125 I]FMIC and [ 125 I]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.

  11. Group X Aldehyde Dehydrogenases of Pseudomonas aeruginosa PAO1 Degrade Hydrazones

    OpenAIRE

    Taniyama, Kosuke; Itoh, Hideomi; Takuwa, Atsushi; Sasaki, Yasuyuki; Yajima, Shunsuke; Toyofuku, Masanori; Nomura, Nobuhiko; Takaya, Naoki

    2012-01-01

    Hydrazones are natural and synthetic compounds containing a C=N-N moiety. Here we found that the opportunistic pathogen Pseudomonas aeruginosa PAO1 produced NAD+- or NADP+-dependent hydrazone dehydrogenase (HDH), which converts hydrazones to the corresponding hydrazides and acids rather than to the simple hydrolytic product aldehydes. Gene cloning indicated that the HDH is part of the group X aldehyde dehydrogenase (ALDH) family, which is distributed among bacteria, although the physiological...

  12. Aldehyde Dehydrogenase 2 Polymorphism Is a Predictor of Smoking Cessation.

    Science.gov (United States)

    Masaoka, Hiroyuki; Gallus, Silvano; Ito, Hidemi; Watanabe, Miki; Yokomizo, Akira; Eto, Masatoshi; Matsuo, Keitaro

    2017-09-01

    Smoking cessation has been known to be associated with drinking behaviors, which are influenced by polymorphisms in genes encoding alcohol metabolizing enzymes. The aim was to evaluate the impact of aldehyde dehydrogenase 2 (ALDH2, rs671) and alcohol dehydrogenase 1B (ADH1B, rs1229984) polymorphisms together with drinking behaviors on smoking cessation. We conducted a cross-sectional study with 1137 former smokers and 1775 current smokers without any cancer at Aichi Cancer Center Hospital between 2001 and 2005. Unconditional logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for successful smoking cessation by comparing former smokers (quitters) with current smokers (non-quitters). Older age, lower amount of cumulative smoking exposure, lower number of cigarettes per day, younger age of smoking initiation, shorter smoking duration, longer time to first cigarette in the morning, and lower amount of drinking among ever drinkers were predictors of smoking cessation. After careful adjustment for age, sex, smoking patterns, and drinking status, the ORs for smoking cessation among subjects with ALDH2 Glu/Lys and Lys/Lys were 1.02 (95% CI 0.84-1.23) and 1.78 (95% CI 1.23-2.58) compared with those with ALDH2 Glu/Glu, respectively Mediation analyses confirmed that the effect of ALDH2 Lys/Lys on smoking cessation was independent by dinking behaviors. No statistically significant association between ADH1B polymorphism and smoking cessation was observed. In our Japanese population, ALDH2 polymorphism predicts smoking cessation, independent by drinking behaviors. Interventions for promoting smoking cessation by ALDH2 polymorphism may be useful in Asian populations. We newly show that subjects with ALDH2 Lys/Lys genotype in a functional polymorphism, rs671, are more likely to quit smoking than those with ALDH2 Glu allele in a Japanese population. Our finding suggests that ALDH2 polymorphism may be useful for promoting smoking

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-04-07

    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. 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

  14. Correlation of loss of activity of human aldehyde dehydrogenase with reaction of bromoacetophenone with glutamic acid-268 and cysteine-302 residues. Partial-sites reactivity of aldehyde dehydrogenase.

    Science.gov (United States)

    Abriola, D P; MacKerell, A D; Pietruszko, R

    1990-01-01

    Bromoacetophenone (2-bromo-1-phenylethanone) has been characterized as an affinity reagent for human aldehyde dehydrogenase (EC 1.2.1.3) [MacKerell, MacWright & Pietruszko (1986) Biochemistry 25, 5182-5189], and has been shown to react specifically with the Glu-268 residue [Abriola, Fields, Stein, MacKerell & Pietruszko (1987) Biochemistry 26, 5679-5684] with an apparent inactivation stoichiometry of two molecules of bromoacetophenone per molecule of enzyme. The specificity of bromoacetophenone for reaction with Glu-268, however, is not absolute, owing to the extreme reactivity of this reagent. When bromo[14C]acetophenone was used to label the human cytoplasmic E1 isoenzyme radioactively and tryptic fragmentation was carried out, peptides besides that containing Glu-268 were found to have reacted with reagent. These peptides were purified by h.p.l.c. and analysed by sequencing and scintillation counting to quantify radioactive label in the material from each cycle of sequencing. Reaction of bromoacetophenone with the aldehyde dehydrogenase molecule during enzyme activity loss occurs with two residues, Glu-268 and Cys-302. The activity loss, however, appears to be proportional to incorporation of label at Glu-268. The large part of incorporation of label at Cys-302 occurs after the activity loss is essentially complete. With both Glu-268 and Cys-302, however, the incorporation of label stops after one molecule of bromoacetophenone has reacted with each residue. Reaction with other residues continues after activity loss is complete. PMID:1968743

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

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

    1990-01-01

    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 of 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

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

    Science.gov (United States)

    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.

  18. Modulation of the reactivity of the essential cysteine residue of betaine aldehyde dehydrogenase from Pseudomonas aeruginosa.

    Science.gov (United States)

    González-Segura, Lilian; Velasco-García, Roberto; Muñoz-Clares, Rosario A

    2002-02-01

    Betaine aldehyde dehydrogenase (BADH) catalyses the irreversible NAD(P)(+)-dependent oxidation of betaine aldehyde to glycine betaine. In the human opportunistic pathogen Pseudomonas aeruginosa this reaction is an obligatory step in the assimilation of carbon and nitrogen when bacteria are growing in choline or choline precursors. As with every aldehyde dehydrogenase studied so far, BADH possesses an essential cysteine residue involved in the formation of the intermediate thiohemiacetal with the aldehyde substrate. We report here that the chemical modification of this residue is conveniently measured by the loss in enzyme activity, which allowed us to explore its reactivity in a pH range around neutrality. The pH dependence of the observed second-order rate constant of BADH inactivation by methyl methanethiosulphonate (MMTS) suggests that at low pH values the essential cysteine residue exists as thiolate by the formation of an ion pair with a positively charged residue. The estimated macroscopic pK values are 8.6 and 4.0 for the free and ion-pair-forming thiolate respectively. The reactivity towards MMTS of both thiolate forms is notably lower than that of model compounds of similar pK, suggesting a considerable steric inhibition by the structure of the protein. Binding of the dinucleotides rapidly induced a significant and transitory increment of thiolate reactivity, followed by a relatively slow change to an almost unreactive form. Thus it seems that to gain protection against oxidation without compromising catalytic efficiency, BADH from P. aeruginosa has evolved a complex and previously undescribed mechanism, involving several conformational rearrangements of the active site, to suit the reactivity of the essential thiol to the availability of coenzyme and substrate.

  19. Heterologous Expression of Aldehyde Dehydrogenase in Lactococcus lactis for Acetaldehyde Detoxification at Low pH.

    Science.gov (United States)

    Lyu, Yunbin; LaPointe, Gisèle; Zhong, Lei; Lu, Jing; Zhang, Chong; Lu, Zhaoxin

    2018-02-01

    Aldehyde dehydrogenase (E.C. 1.2.1.x) can catalyze detoxification of acetaldehydes. A novel acetaldehyde dehydrogenase (istALDH) from the non-Saccharomyces yeast Issatchenkia terricola strain XJ-2 has been previously characterized. In this work, Lactococcus lactis with the NIsin Controlled Expression (NICE) System was applied to express the aldehyde dehydrogenase gene (istALDH) in order to catalyze oxidation of acetaldehyde at low pH. A recombinant L. lactis NZ3900 was obtained and applied for the detoxification of acetaldehyde as whole-cell biocatalysts. The activity of IstALDH in L. lactis NZ3900 (pNZ8148-istALDH) reached 36.4 U mL -1 when the recombinant cells were induced with 50 ng mL -1 nisin at 20 °C for 2 h. The IstALDH activity of recombinant L. lactis cells showed higher stability at 37 °C and pH 4.0 compared with the crude enzyme. L. lactis NZ3900 (pNZ8148-istALDH) could convert acetaldehyde at pH 2.0 while the crude enzyme could not. Moreover, the resting cells of L. lactis NZ3900 (pNZ8148-istALDH) showed a 2.5-fold higher activity and better stability in catalyzing oxidation of acetaldehyde at pH 2.0 compared with that of Escherichia coli expressing the IstALDH. Taken together, the L. lactis cells expressing recombinant IstALDH are potential whole-cell biocatalysts that can be applied in the detoxification of aldehydes.

  20. Group X aldehyde dehydrogenases of Pseudomonas aeruginosa PAO1 degrade hydrazones.

    Science.gov (United States)

    Taniyama, Kosuke; Itoh, Hideomi; Takuwa, Atsushi; Sasaki, Yasuyuki; Yajima, Shunsuke; Toyofuku, Masanori; Nomura, Nobuhiko; Takaya, Naoki

    2012-03-01

    Hydrazones are natural and synthetic compounds containing a C=N-N moiety. Here we found that the opportunistic pathogen Pseudomonas aeruginosa PAO1 produced NAD(+)- or NADP(+)-dependent hydrazone dehydrogenase (HDH), which converts hydrazones to the corresponding hydrazides and acids rather than to the simple hydrolytic product aldehydes. Gene cloning indicated that the HDH is part of the group X aldehyde dehydrogenase (ALDH) family, which is distributed among bacteria, although the physiological roles of the ALDH family remain unknown. The PAO1 strain upregulated HDH in the presence of the hydrazone adipic acid bis(ethylidene hydrazide) (AEH). Gene disruption of the HDH-encoding hdhA (PA4022) decreased growth rates in culture medium containing AEH as the sole carbon source, and this effect was more obvious in the double gene disruption of hdhA and its orthologous exaC (PA1984), indicating that these genes are responsible for hydrazone utilization. Recombinant proteins of group X ALDHs from Escherichia coli, Paracoccus denitrificans, and Ochrobactrum anthropi also acted as HDHs in that they produced HDH activity in the cells and degraded hydrazones. These findings indicated the physiological roles of group X ALDHs in bacteria and showed that they comprise a distinct ALDH subfamily.

  1. Genomic organization and expression of the human fatty aldehyde dehydrogenase gene (FALDH)

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, G.R.; Markova, N.G.; Compton, J.G. [National Institutes of Health, Bethesda, MD (United States)] [and others

    1997-01-15

    Mutations in the fatty aldehyde dehydrogenase (FALDH) gene cause Sjoegren-Larsson syndrome (SLS) - a disease characterized by mental retardation, spasticity, and congenital ichthyosis. To facilitate mutation analysis in SLS and to study the pathogenesis of FALDH deficiency, we have determined the structural organization and characterized expression of the FALDH (proposed designation ALDH10) gene. The gene consists of 10 exons spanning about 30.5 kb. A TATA-less promoter is associated with the major transcription initiation site found to be 258 hp upstream of the ATG codon. The G4C-rich sequences surrounding the transcription initiation site encompassed regulatory elements that interacted with proteins in HeLa nuclear extracts and were able to promote transcription in vitro. FALDH is widely expressed as three transcripts of 2, 3.8, and 4.0 kb, which originate from multiple polyadenylation signals in the 3{prime} UTR. An alternatively spliced mRNA was detected that contains an extra exon and encodes an enzyme that is likely to have altered membrane-binding properties. The FALDH gene lies only 50-85 kb from ALDH3, an aldehyde dehydrogenase gene that has homologous sequence and intron/exon structure. 25 refs., 4 figs., 1 tab.

  2. Blood Leukocyte Counts and Genetic Polymorphisms of Alcohol Dehydrogenase-1B and Aldehyde Dehydrogenase-2 in Japanese Alcoholic Men.

    Science.gov (United States)

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

    2016-03-01

    Roughly 40% of East Asians have inactive aldehyde dehydrogenase-2 (ALDH2) encoded by the ALDH2*2 allele, and 90% have highly active alcohol dehydrogenase-1B (ADH1B) encoded by the ADH1B*2 allele. Macrocytosis and macrocytic anemia in alcoholics have been associated with ADH1B and ALDH2 gene variants which increase acetaldehyde (AcH) levels. We investigated the relationship between ADH1B*2, ALDH2*2, and leukocyte counts of Japanese alcoholic men (N = 1,661). After adjusting for age, drinking habits, smoking habits, body mass index, presence of liver cirrhosis, and serum levels of C-reactive protein, we found that total and differential leukocyte counts were lower in the presence of the ALDH2*1/*2 genotype (vs. ALDH2*1/*1 genotype). ALDH2*2/*2 carriers were not found in our study population. Leukocyte, granulocyte, and monocyte counts were also lower in the presence of ADH1B*2 (vs. ADH1B*1/*1 genotype), but the lymphocyte count was higher. The ALDH2*1/*2 genotype was associated with leukocytopenia (counts. The total and differential blood leukocyte counts of Japanese alcoholics were strongly affected by their ADH1B and ALDH2 gene variants. High AcH exposure levels probably play a critical role in the suppression of blood leukocyte counts in alcoholics. Copyright © 2016 by the Research Society on Alcoholism.

  3. The Diagnostic Significance of Serum Alcohol Dehydrogenase Isoenzymes and Aldehyde Dehydrogenase Activity in Urinary Bladder Cancer Patients.

    Science.gov (United States)

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

    2017-07-01

    The aim of this study was to investigate a potential role of alcohol dehydrogenase and aldehyde dehydrogenase as tumor markers for urinary bladder cancer. Serum samples were obtained from 41 patients with bladder cancer and 52 healthy individuals. Class III and IV of ADH and total ADH activity were measured by the photometric method. For measurement of class I and II ADH and ALDH activity, the fluorometric method was employed. Significantly higher total activity of ADH was found in sera of both, low-grade and high-grade bladder cancer patients. The diagnostic sensitivity for total ADH activity was 81.5%, specificity 98.1%, positive (PPV) and negative (NPV) predictive values were 97.4% and 92.3% respectively. Area under ROC curve for total ADH activity was 0.848. A potential role of total ADH activity as a marker for bladder cancer, is herein proposed. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

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

    Science.gov (United States)

    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.

  5. Structure and mechanism of benzaldehyde dehydrogenase from Pseudomonas putida ATCC 12633, a member of the Class 3 aldehyde dehydrogenase superfamily.

    Science.gov (United States)

    Zahniser, Megan P D; Prasad, Shreenath; Kneen, Malea M; Kreinbring, Cheryl A; Petsko, Gregory A; Ringe, Dagmar; McLeish, Michael J

    2017-03-01

    Benzaldehyde dehydrogenase from Pseudomonas putida (PpBADH) belongs to the Class 3 aldehyde dehydrogenase (ALDH) family. The Class 3 ALDHs are unusual in that they are generally dimeric (rather than tetrameric), relatively non-specific and utilize both NAD+ and NADP+. To date, X-ray structures of three Class 3 ALDHs have been determined, of which only two have cofactor bound, both in the NAD+ form. Here we report the crystal structure of PpBADH in complex with NADP+ and a thioacyl intermediate adduct. The overall architecture of PpBADH resembles that of most other members of the ALDH superfamily, and the cofactor binding residues are well conserved. Conversely, the pattern of cofactor binding for the rat Class 3 ALDH differs from that of PpBADH and other ALDHs. This has been interpreted in terms of a different mechanism for the rat enzyme. Comparison with the PpBADH structure, as well as multiple sequence alignments, suggest that one of two conserved glutamates, at positions 215 (209 in rat) and 337 (333 in rat), would act as the general base necessary to hydrolyze the thioacyl intermediate. While the latter is the general base in the rat Class 3 ALDH, site-specific mutagenesis indicates that Glu215 is the likely candidate for PpBADH, a result more typical of the Class 1 and 2 ALDH families. Finally, this study shows that hydride transfer is not rate limiting, lending further credence to the suggestion that PpBADH is more similar to the Class 1 and 2 ALDHs than it is to other Class 3 ALDHs. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Corneal aldehyde dehydrogenase and glutathione S-transferase activity after excimer laser keratectomy in guinea pigs.

    Science.gov (United States)

    Bilgihan, K; Bilgihan, A; Hasanreisoğlu, B; Turkozkan, N

    1998-03-01

    The free radical balance of the eye may be changed by excimer laser keratectomy. Previous studies have demonstrated that excimer laser keratectomy increases the corneal temperature, decreases the superoxide dismutase activity of the aqueous, and induces lipid peroxidation in the superficial corneal stroma. Aldehyde dehydrogenase (ALDH) and glutathione S-transferase (GST) are known to play an important role in corneal metabolism, particularly in detoxification of aldehydes, which are generated from free radical reactions. In three groups of guinea pigs mechanical corneal de-epithelialisation was performed in group I, superficial corneal photoablation in group II, and deep corneal photoablation in group III, and the corneal ALDH and GST activities measured after 48 hours. The mean ALDH and GST activities of group I and II showed no differences compared with the controls (p > 0.05). The corneal ALDH activities were found to be significantly decreased (p < 0.05) and GST activities increased (p < 0.05) in group III. These results suggest that excimer laser treatment of high myopia may change the ALDH and GST activities, metabolism, and free radical balance of the cornea.

  7. Human aldehyde dehydrogenase genes: alternatively spliced transcriptional variants and their suggested nomenclature.

    Science.gov (United States)

    Black, William J; Stagos, Dimitrios; Marchitti, Satori A; Nebert, Daniel W; Tipton, Keith F; Bairoch, Amos; Vasiliou, Vasilis

    2009-11-01

    The human aldehyde dehydrogenase (ALDH) gene superfamily consists of 19 genes encoding enzymes critical for NAD(P)-dependent oxidation of endogenous and exogenous aldehydes, including drugs and environmental toxicants. Mutations in ALDH genes are the molecular basis of several disease states (e.g. Sjögren-Larsson syndrome, pyridoxine-dependent seizures, and type II hyperprolinemia) and may contribute to the etiology of complex diseases such as cancer and Alzheimer's disease. The aim of this nomenclature update was to identify splice transcriptional variants principally for the human ALDH genes. Data-mining methods were used to retrieve all human ALDH sequences. Alternatively spliced transcriptional variants were determined based on (i) criteria for sequence integrity and genomic alignment; (ii) evidence of multiple independent cDNA sequences corresponding to a variant sequence; and (iii) if available, empirical evidence of variants from the literature. Alternatively spliced transcriptional variants and their encoded proteins exist for most of the human ALDH genes; however, their function and significance remain to be established. When compared with the human genome, rat and mouse include an additional gene, Aldh1a7, in the ALDH1A subfamily. To avoid confusion when identifying splice variants in various genomes, nomenclature guidelines for the naming of such alternative transcriptional variants and proteins are recommended herein. In addition, a web database (www.aldh.org) has been developed to provide up-to-date information and nomenclature guidelines for the ALDH superfamily.

  8. Identification and characterisation of Aedes aegypti aldehyde dehydrogenases involved in pyrethroid metabolism.

    Directory of Open Access Journals (Sweden)

    Nongkran Lumjuan

    Full Text Available Pyrethroid insecticides, especially permethrin and deltamethrin, have been used extensively worldwide for mosquito control. However, insecticide resistance can spread through a population very rapidly under strong selection pressure from insecticide use. The upregulation of aldehyde dehydrogenase (ALDH has been reported upon pyrethroid treatment. In Aedes aegypti, the increase in ALDH activity against the hydrolytic product of pyrethroid has been observed in DDT/permethrin-resistant strains. The objective of this study was to identify the role of individual ALDHs involved in pyrethroid metabolism.Three ALDHs were identified; two of these, ALDH9948 and ALDH14080, were upregulated in terms of both mRNA and protein levels in a DDT/pyrethroid-resistant strain of Ae. aegypti. Recombinant ALDH9948 and ALDH14080 exhibited oxidase activities to catalyse the oxidation of a permethrin intermediate, phenoxybenzyl aldehyde (PBald, to phenoxybenzoic acid (PBacid.ALDHs have been identified in association with permethrin resistance in Ae. aegypti. Characterisation of recombinant ALDHs confirmed the role of this protein in pyrethroid metabolism. Understanding the biochemical and molecular mechanisms of pyrethroid resistance provides information for improving vector control strategies.

  9. Effects of Alda-1, an Aldehyde Dehydrogenase-2 Agonist, on Hypoglycemic Neuronal Death.

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    Tetsuhiko Ikeda

    Full Text Available Hypoglycemic encephalopathy (HE is caused by a lack of glucose availability to neuronal cells, and no neuroprotective drugs have been developed as yet. Studies on the pathogenesis of HE and the development of new neuroprotective drugs have been conducted using animal models such as the hypoglycemic coma model and non-coma hypoglycemia model. However, both models have inherent problems, and establishment of animal models that mimic clinical situations is desirable. In this study, we first developed a short-term hypoglycemic coma model in which rats could be maintained in an isoelectric electroencephalogram (EEG state for 2 min and subsequent hyperglycemia without requiring anti-seizure drugs and an artificial ventilation. This condition caused the production of 4-hydroxy-2-nonenal (4-HNE, a cytotoxic aldehyde, in neurons of the hippocampus and cerebral cortex, and a marked increase in neuronal death as evaluated by Fluoro-Jade B (FJB staining. We also investigated whether N-(1,3-benzodioxole-5-ylmethyl-2,6-dichlorobenzamide (Alda-1, a small-molecule agonist of aldehyde dehydrogenase-2, could attenuate 4-HNE levels and reduce hypoglycemic neuronal death. After confirming that EEG recordings remained isoelectric for 2 min, Alda-1 (8.5 mg/kg or vehicle (dimethyl sulfoxide; DMSO was administered intravenously with glucose to maintain a blood glucose level of 250 to 270 mg/dL. Fewer 4-HNE and FJB-positive cells were observed in the cerebral cortex of Alda-1-treated rats than in DMSO-treated rats 24 h after glucose administration (P = 0.002 and P = 0.020. Thus, activation of the ALDH2 pathway could be a molecular target for HE treatment, and Alda-1 is a potentially neuroprotective agent that exerts a beneficial effect on neurons when intravenously administered simultaneously with glucose.

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

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    Feng-Xia Tian

    Full Text Available 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.

  11. Roles of histamine on the expression of aldehyde dehydrogenase 1 in endometrioid adenocarcinoma cell line

    Science.gov (United States)

    Wang, Yi; Jiang, Yang; Ikeda, Jun-ichiro; Tian, Tian; Sato, Atsushi; Ohtsu, Hiroshi; Morii, Eiichi

    2014-01-01

    Cancer-initiating cells (CICs) are a limited number of cells that are essential for maintenance, recurrence, and metastasis of tumors. Aldehyde dehydrogenase 1 (ALDH1) has been recognized as a marker of CICs. We previously reported that ALDH1-high cases of uterine endometrioid adenocarcinoma showed poor prognosis, and that ALDH1 high population was more tumorigenic, invasive, and resistant to apoptosis than ALDH1 low population. Histamine plays a critical role in cancer cell proliferation, migration, and invasion. Here, we examined the effect of histamine on ALDH1 expression in endometrioid adenocarcinoma cell line. The addition of histamine increased ALDH1 high population, which was consistent with the result that histamine enhanced the invasive ability and the resistance to anticancer drug. Among 4 types of histamine receptors, histamine H1 and H2 receptor (H1R and H2R) were expressed in endometrioid adenocarcinoma cell line. The addition of H1R agonist but not H2R agonist increased ALDH1. The antagonist H1R but not H2R inhibited the effect of histamine on ALDH1 expression. These results indicated that histamine increased the expression of ALDH1 via H1R but not H2R. These findings may provide the evidence for exploring a new strategy to suppress CICs by inhibiting ALDH1 expression with histamine. PMID:25045085

  12. Inhibitory effect of Nodal on the expression of aldehyde dehydrogenase 1 in endometrioid adenocarcinoma of uterus.

    Science.gov (United States)

    Wang, Yi; Jiang, Yang; Tian, Tian; Hori, Yumiko; Wada, Naoki; Ikeda, Jun-ichiro; Morii, Eiichi

    2013-11-01

    Cancers consist of heterogeneous populations. Recently, it has been demonstrated that cells with tumorigenic potential are limited to a small population, called cancer-initiating cells (CICs). Aldehyde dehydrogenase 1 (ALDH1) is one of the markers of CICs. We previously reported that ALDH1-high cases of uterine endometrioid adenocarcinoma showed poor prognosis, and ALDH1-high population of endometrioid adenocarcinoma cell line was more tumorigenic, resistant to anti-cancer drugs, and invasive than ALDH1-low population. Here, the regulatory signaling for ALDH1 was examined. The inhibition of TGF-β signaling increased ALDH1-high population. Among TGF-β family members, Nodal expression and ALDH1 expression levels were mutually exclusive. Immunohistochemical analysis on clinical samples revealed Nodal-high tumor cells to be ALDH-low and vise versa, suggesting that Nodal may inhibit ALDH1 expression via stimulating TGF-β signaling in uterine endometrioid adenocarcinoma. In fact, the addition of Nodal to endometrioid adenocarcinoma cell line reduced ALDH1-high population. Although ALDH1 mRNA level was not affected, the amount of ALDH1 protein appeared to be reduce by Nodal through ubiquitine-proteasome pathway. The regulation of TGF-β signaling might be a novel therapeutic target of CICs in endometrioid adenocarcinoma. Copyright © 2013. Published by Elsevier Inc.

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

    Science.gov (United States)

    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.

  14. Roles of histamine on the expression of aldehyde dehydrogenase 1 in endometrioid adenocarcinoma cell line.

    Science.gov (United States)

    Wang, Yi; Jiang, Yang; Ikeda, Jun-Ichiro; Tian, Tian; Sato, Atsushi; Ohtsu, Hiroshi; Morii, Eiichi

    2014-10-01

    Cancer-initiating cells (CICs) are a limited number of cells that are essential for maintenance, recurrence, and metastasis of tumors. Aldehyde dehydrogenase 1 (ALDH1) has been recognized as a marker of CICs. We previously reported that ALDH1-high cases of uterine endometrioid adenocarcinoma showed poor prognosis, and that ALDH1 high population was more tumorigenic, invasive, and resistant to apoptosis than ALDH1 low population. Histamine plays a critical role in cancer cell proliferation, migration, and invasion. Here, we examined the effect of histamine on ALDH1 expression in endometrioid adenocarcinoma cell line. The addition of histamine increased ALDH1 high population, which was consistent with the result that histamine enhanced the invasive ability and the resistance to anticancer drug. Among 4 types of histamine receptors, histamine H1 and H2 receptor (H1R and H2R) were expressed in endometrioid adenocarcinoma cell line. The addition of H1R agonist but not H2R agonist increased ALDH1. The antagonist H1R but not H2R inhibited the effect of histamine on ALDH1 expression. These results indicated that histamine increased the expression of ALDH1 via H1R but not H2R. These findings may provide the evidence for exploring a new strategy to suppress CICs by inhibiting ALDH1 expression with histamine. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  15. Interaction of Aldehyde dehydrogenase with acetaminophen as examined by spectroscopies and molecular docking

    Directory of Open Access Journals (Sweden)

    Ayodele O. Kolawole

    2017-07-01

    Full Text Available The interaction of acetaminophen, a non-substrate anionic ligand, with Aldehyde Dehydrogenase was studied by fluorescence, UV–Vis absorption, and circular dichroism spectroscopies under simulated physiological conditions. The fluorescence spectra and data generated showed that acetaminophen binding to ALDH is purely dynamic quenching mechanism. The acetaminophen-ALDH is kinetically rapid reversible interaction with a binding constant, Ka, of 4.91×103 L mol−1. There was an existence of second binding site of ALDH for acetaminophen at saturating acetaminophen concentration. The binding sites were non-cooperative. The thermodynamic parameters obtained suggest that Van der Waal force and hydrogen bonding played a major role in the binding of acetaminophen to ALDH. The interaction caused perturbation of the ALDH structures with an obvious reduction in the α-helix. The binding distance of 4.43 nm was obtained between Acetaminophen and ALDH. Using Ficoll 400 as macro-viscosogen and glycerol as micro-viscosogen, Stoke-Einstein empirical plot demonstrated that acetaminophen-ALDH binding was diffusion controlled. Molecular docking showed the participation of some amino acids in the complex formation with −5.3 kcal binding energy. With these, ALDH might not an excipient detoxifier of acetaminophen but could be involved in its pegylation/encapsulation.

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

    International Nuclear Information System (INIS)

    Nakamura, Tomofumi; Ichinose, Hirofumi; Wariishi, Hiroyuki

    2010-01-01

    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 conserved domains of ALDHs. Moreover, a novel glycine-rich motif 'GxGxxxG' was located at the NAD + -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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Tomofumi [Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Fukuoka Institute of Health and Environmental Sciences, 39 Mukaizano, Dazaifu-shi, Fukuoka 818-0135 (Japan); Ichinose, Hirofumi [Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Wariishi, Hiroyuki, E-mail: hirowari@agr.kyushu-u.ac.jp [Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Bio-Architecture Center, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Innovation Center for Medical Redox Navigation, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

    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 conserved 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.

  18. Characterization of aldehyde dehydrogenase isozymes in ovarian cancer tissues and sphere cultures

    International Nuclear Information System (INIS)

    Saw, Yu-Ting; Thompson, David; Vasiliou, Vasilis; Berkowitz, Ross S; Ng, Shu-Wing; Yang, Junzheng; Ng, Shu-Kay; Liu, Shubai; Singh, Surendra; Singh, Margit; Welch, William R; Tsuda, Hiroshi; Fong, Wing-Ping

    2012-01-01

    Aldehyde dehydrogenases belong to a superfamily of detoxifying enzymes that protect cells from carcinogenic aldehydes. Of the superfamily, ALDH1A1 has gained most attention because current studies have shown that its expression is associated with human cancer stem cells. However, ALDH1A1 is only one of the 19 human ALDH subfamilies currently known. The purpose of the present study was to determine if the expression and activities of other major ALDH isozymes are associated with human ovarian cancer and ovarian cancer sphere cultures. Immunohistochemistry was used to delineate ALDH isozyme localization in clinical ovarian tissues. Western Blot analyses were performed on lysates prepared from cancer cell lines and ovarian cancer spheres to confirm the immunohistochemistry findings. Quantitative reverse transcription-polymerase chain reactions were used to measure the mRNA expression levels. The Aldefluor® assay was used to measure ALDH activity in cancer cells from the four tumor subtypes. Immunohistochemical staining showed significant overexpression of ALDH1A3, ALDH3A2, and ALDH7A1 isozymes in ovarian tumors relative to normal ovarian tissues. The expression and activity of ALDH1A1 is tumor type-dependent, as seen from immunohistochemisty, Western blot analysis, and the Aldefluor® assay. The expression was elevated in the mucinous and endometrioid ovarian epithelial tumors than in serous and clear cell tumors. In some serous and most clear cell tumors, ALDH1A1 expression was found in the stromal fibroblasts. RNA expression of all studied ALDH isozymes also showed higher expression in endometrioid and mucinous tumors than in the serous and clear cell subtypes. The expression of ALDH enzymes showed tumor type-dependent induction in ovarian cancer cells growing as sphere suspensions in serum-free medium. The results of our study indicate that ALDH enzyme expression and activity may be associated with specific cell types in ovarian tumor tissues and vary according to

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    Science.gov (United States)

    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

  2. The dental pulp stem cell niche based on aldehyde dehydrogenase 1 expression

    Science.gov (United States)

    Machado, CV; Passos, ST; Campos, TMC; Bernardi, L; Vilas-Bôas, DS; Nör, JE; Telles, PDS; Nascimento, IL

    2015-01-01

    Aim To detect cells expressing the stem cell marker ALDH1 (aldehyde dehydrogenase1) in the pulp of human permanent teeth and to investigate the expression of ALDH1 in isolated dental pulp cells. Methodology Pulp tissue was collected and processed for immunohistochemistry to detect ALDH1, STRO-1 and CD90 positive cells. In addition, cells were isolated and analyzed by flow cytometry for ALDH1 activity, and for the cell surface markers CD44, CD73, CD90, STRO-1 and CD45. Cells were also examined for multi-differentiation capacity. Within these cells, an ALDH1+ cell subpopulation was selected and evaluated for multi-differentiation capacity. Results The immunohistochemistry analyses showed that ALDH1, CD90 and STRO-1 positive cells were located mainly in the perivascular areas and nerve fibres of dental pulps. Cells on the fifth passage had high expression for CD44, CD73 and CD90, whereas moderate labeling was observed for STRO-1 and ALDH1 in flow cytometry analysis. On the same passages, cells were able to differentiate into osteogenic, adipogenic and chondrogenic lineages. The ALDH1+ cell subpopulation also demonstrated multi-lineage differentiation ability. Conclusions Dental pulp stem cells reside in the vicinity of blood vessels and nerve fibres, indicating the possible existence of more than one stem cell niche in dental pulps. Furthermore, ALDH1 was expressed by isolated dental pulp cells, which had mesenchymal stem cell characteristics. Thus, it can be suggested that ALDH1 may be used as a DPSC marker. PMID:26198909

  3. Characterization of Cardiac-Resident Progenitor Cells Expressing High Aldehyde Dehydrogenase Activity

    Directory of Open Access Journals (Sweden)

    Marc-Estienne Roehrich

    2013-01-01

    Full Text Available High aldehyde dehydrogenase (ALDH activity has been associated with stem and progenitor cells in various tissues. Human cord blood and bone marrow ALDH-bright (ALDHbr cells have displayed angiogenic activity in preclinical studies and have been shown to be safe in clinical trials in patients with ischemic cardiovascular disease. The presence of ALDHbr cells in the heart has not been evaluated so far. We have characterized ALDHbr cells isolated from mouse hearts. One percent of nonmyocytic cells from neonatal and adult hearts were ALDHbr. ALDHvery-br cells were more frequent in neonatal hearts than adult. ALDHbr cells were more frequent in atria than ventricles. Expression of ALDH1A1 isozyme transcripts was highest in ALDHvery-br cells, intermediate in ALDHbr cells, and lowest in ALDHdim cells. ALDH1A2 expression was highest in ALDHvery-br cells, intermediate in ALDHdim cells, and lowest in ALDHbr cells. ALDH1A3 and ALDH2 expression was detectable in ALDHvery-br and ALDHbr cells, unlike ALDHdim cells, albeit at lower levels compared with ALDH1A1 and ALDH1A2. Freshly isolated ALDHbr cells were enriched for cells expressing stem cell antigen-1, CD34, CD90, CD44, and CD106. ALDHbr cells, unlike ALDHdim cells, could be grown in culture for more than 40 passages. They expressed sarcomeric α-actinin and could be differentiated along multiple mesenchymal lineages. However, the proportion of ALDHbr cells declined with cell passage. In conclusion, the cardiac-derived ALDHbr population is enriched for progenitor cells that exhibit mesenchymal progenitor-like characteristics and can be expanded in culture. The regenerative potential of cardiac-derived ALDHbr cells remains to be evaluated.

  4. Aldehyde Dehydrogenase 1A1: Friend or Foe to Female Metabolism?

    Directory of Open Access Journals (Sweden)

    Jennifer M. Petrosino

    2014-03-01

    Full Text Available In this review, we summarize recent advances in understanding vitamin A-dependent regulation of sex-specific differences in metabolic diseases, inflammation, and certain cancers. We focus on the characterization of the aldehyde dehydrogenase-1 family of enzymes (ALDH1A1, ALDH1A2, ALDH1A3 that catalyze conversion of retinaldehyde to retinoic acid. Additionally, we propose a “horizontal transfer of signaling” from estrogen to retinoids through the action of ALDH1A1. Although estrogen does not directly influence expression of Aldh1a1, it has the ability to suppress Aldh1a2 and Aldh1a3, thereby establishing a female-specific mechanism for retinoic acid generation in target tissues. ALDH1A1 regulates adipogenesis, abdominal fat formation, glucose tolerance, and suppression of thermogenesis in adipocytes; in B cells, ALDH1A1 plays a protective role by inducing oncogene suppressors Rara and Pparg. Considering the conflicting responses of Aldh1a1 in a multitude of physiological processes, only tissue-specific regulation of Aldh1a1 can result in therapeutic effects. We have shown through successful implantation of tissue-specific Aldh1a1−/− preadipocytes that thermogenesis can be induced in wild-type adipose tissues to resolve diet-induced visceral obesity in females. We will briefly discuss the emerging role of ALDH1A1 in multiple myeloma, the regulation of reproduction, and immune responses, and conclude by discussing the role of ALDH1A1 in future therapeutic applications.

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

    Science.gov (United States)

    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.

  6. Aldehyde dehydrogenase 1A1 circumscribes high invasive glioma cells and predicts poor prognosis

    Science.gov (United States)

    Xu, Sen-Lin; Liu, Sha; Cui, Wei; Shi, Yu; Liu, Qin; Duan, Jiang-Jie; Yu, Shi-Cang; Zhang, Xia; Cui, You-Hong; Kung, Hsiang-Fu; Bian, Xiu-Wu

    2015-01-01

    Glioma is the most aggressive brain tumor with high invasiveness and poor prognosis. More reliable, sensitive and practical biomarkers to reveal glioma high invasiveness remain to be explored for the guidance of therapy. We herein evaluated the diagnostic and prognostic value of aldehyde dehydrogenase 1A1 (ALDH1A1) in the glioma specimens from 237 patients, and found that ADLH1A1 was frequently overexpressed in the high-grade glioma (WHO grade III-IV) as compared to the low-grade glioma (WHO grade I-II) patients. The tumor cells with ALDH1A1 expression were more abundant in the region between tumor and the borderline of adjacent tissue as compared to the central part of the tumor. ALDH1A1 overexpression was associated with poor differentiation and dismal prognosis. Notably, the overall and disease-free survivals of the patients who had ALDH1A1+ tumor cells sparsely located in the adjacent tissue were much worse. Furthermore, ALDH1A1 expression was correlated with the “classical-like” (CL) subtype as we examined GBM specimens from 72 patients. Multivariate Cox regression analysis revealed that ALDH1A1 was an independent marker for glioma patients’ outcome. Mechanistically, both in vitro and in vivo studies revealed that ALDH1A1+ cells isolated from either a glioblastoma cell line U251 or primary glioblastoma cells displayed significant invasiveness, clonogenicity, and proliferation as compared to ALDH1A1- cells, due to increased levels of mRNA and protein for matrix metalloproteinase 2, 7 and 9 (MMP2, MMP7 and MMP9). These results indicate that ALDH1A1+ cells contribute to the progression of glioma including invasion, proliferation and poor prognosis, and suggest that targeting ALDH1A1 may have important implications for the treatment of highly invasive glioma. PMID:26101711

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  9. Aldehyde dehydrogenase activity selects for the holoclone phenotype in prostate cancer cells

    International Nuclear Information System (INIS)

    Doherty, R.E.; Haywood-Small, S.L.; Sisley, K.; Cross, N.A.

    2011-01-01

    Highlights: ► Isolated ALDH Hi PC3 cells preferentially form primitive holoclone-type colonies. ► Primitive holoclone colonies are predominantly ALDH Lo but contain rare ALDH Hi cells. ► Holoclone-forming cells are not restricted to the ALDH Hi population. ► ALDH phenotypic plasticity occurs in PC3 cells (ALDH Lo to ALDH Hi and vice versa). ► ALDH Hi cells are observed but very rare in PC3 spheroids grown in stem cell medium. -- Abstract: Aldehyde dehydrogenase 1 (ALDH) activity is considered to be a marker of cancer stem cells (CSCs) in many tumour models, since these cells are more proliferative and tumourigenic than ALDH Lo cells in experimental models. However it is unclear whether all CSC-like cells are within the ALDH Hi population, or whether all ALDH Hi cells are highly proliferative and tumourigenic. The ability to establish a stem cell hierarchy in vitro, whereby sub-populations of cells have differing proliferative and differentiation capacities, is an alternate indication of the presence of stem cell-like populations within cell lines. In this study, we have examined the interaction between ALDH status and the ability to establish a stem cell hierarchy in PC3 prostate cancer cells. We demonstrate that PC3 cells contain a stem cell hierarchy, and isolation of ALDH Hi cells enriches for the most primitive holoclone population, however holoclone formation is not restricted to ALDH Hi cells. In addition, we show that ALDH activity undergoes phenotypic plasticity, since the ALDH Lo population can develop ALDH Hi populations comparable to parental cells within 2 weeks in culture. Furthermore, we show that the majority of ALDH Hi cells are found within the least primitive paraclone population, which is circumvented by culturing PC3 cells as spheroids in defined medium favouring stem cell characteristics. Although ALDH Hi status enriches for holoclone formation, this activity may be mediated by a minority of ALDH Hi cells.

  10. aldB, an RpoS-dependent gene in Escherichia coli encoding an aldehyde dehydrogenase that is repressed by Fis and activated by Crp.

    OpenAIRE

    Xu, J; Johnson, R C

    1995-01-01

    Escherichia coli aldB was identified as a gene that is negatively regulated by Fis but positively regulated by RpoS. The complete DNA sequence determined in this study indicates that aldB encodes a 56.3-kDa protein which shares a high degree of homology with an acetaldehyde dehydrogenase encoded by acoD of Alcaligenes eutrophus and an aldehyde dehydrogenase encoded by aldA of Vibrio cholerae and significant homology with a group of other aldehyde dehydrogenases from prokaryotes and eukaryotes...

  11. Genome-wide characterization and expression analysis of the aldehyde dehydrogenase (ALDH) gene superfamily under abiotic stresses in cotton.

    Science.gov (United States)

    Guo, Xinlei; Wang, Yuanyuan; Lu, Hejun; Cai, Xiaoyan; Wang, Xingxing; Zhou, Zhongli; Wang, Chunying; Wang, Yuhong; Zhang, Zhenmei; Wang, Kunbo; Liu, Fang

    2017-09-10

    In plants, aldehyde dehydrogenases (ALDHs) function as 'aldehyde scavengers' by removing reactive aldehydes and thus play important roles in stress responses. To date, 30 ALDHs have been identified in Gossypium raimondii, whereas ALDHs have not been studied in Gossypium arboreum or in tetraploid cotton. In this study, we identified 30, 59 and 59 aldehyde dehydrogenase (ALDH) genes from G. arboreum, G. hirsutum and G. barbadense, respectively. Gene structure analysis revealed that members of the same family exhibit similar exon-intron structures and structural domains, and all members of the ALDH18 family possess a distinct AA-kinase domain. Synteny analysis showed that segmental and tandem duplications have played an important role in the expansion and evolution of ALDHs in cotton. Phylogenetic and synteny analysis between G. arboreum and G. raimondii demonstrated that all GaALDHs and GrALDHs are orthologous and that most GaALDHs are located in syntenic blocks corresponding to those of G. raimondii, implying that these genes appeared before the divergence of G. arboreum and G. raimondii and that no expansion of the ALDH superfamily has occurred in these two cotton species. Quantitative real-time PCR analysis revealed that the majority of GaALDHs and GhALDHs are up-regulated under conditions of high salinity and drought, indicating that these genes may be stress responsive. The findings of this study, based on genome-wide identification of ALDHs in Gossypium and analysis of their evolution and expression, provide a foundation for further analysis of ALDHs and suggest potential target genes for improving stress resistance in cotton. Copyright © 2017. Published by Elsevier B.V.

  12. Aldehyde dehydrogenase activity selects for the holoclone phenotype in prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Doherty, R.E.; Haywood-Small, S.L. [Biomedical Research Centre, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom); Sisley, K. [Department of Oncology, Academic Unit of Ophthalmology and Orthopties, University of Sheffield, Sheffield S10 2RX (United Kingdom); Cross, N.A., E-mail: n.cross@shu.ac.uk [Biomedical Research Centre, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Isolated ALDH{sup Hi} PC3 cells preferentially form primitive holoclone-type colonies. Black-Right-Pointing-Pointer Primitive holoclone colonies are predominantly ALDH{sup Lo} but contain rare ALDH{sup Hi} cells. Black-Right-Pointing-Pointer Holoclone-forming cells are not restricted to the ALDH{sup Hi} population. Black-Right-Pointing-Pointer ALDH phenotypic plasticity occurs in PC3 cells (ALDH{sup Lo} to ALDH{sup Hi} and vice versa). Black-Right-Pointing-Pointer ALDH{sup Hi} cells are observed but very rare in PC3 spheroids grown in stem cell medium. -- Abstract: Aldehyde dehydrogenase 1 (ALDH) activity is considered to be a marker of cancer stem cells (CSCs) in many tumour models, since these cells are more proliferative and tumourigenic than ALDH{sup Lo} cells in experimental models. However it is unclear whether all CSC-like cells are within the ALDH{sup Hi} population, or whether all ALDH{sup Hi} cells are highly proliferative and tumourigenic. The ability to establish a stem cell hierarchy in vitro, whereby sub-populations of cells have differing proliferative and differentiation capacities, is an alternate indication of the presence of stem cell-like populations within cell lines. In this study, we have examined the interaction between ALDH status and the ability to establish a stem cell hierarchy in PC3 prostate cancer cells. We demonstrate that PC3 cells contain a stem cell hierarchy, and isolation of ALDH{sup Hi} cells enriches for the most primitive holoclone population, however holoclone formation is not restricted to ALDH{sup Hi} cells. In addition, we show that ALDH activity undergoes phenotypic plasticity, since the ALDH{sup Lo} population can develop ALDH{sup Hi} populations comparable to parental cells within 2 weeks in culture. Furthermore, we show that the majority of ALDH{sup Hi} cells are found within the least primitive paraclone population, which is circumvented by culturing PC3 cells as spheroids in

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

    Science.gov (United States)

    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

  14. Comparative genomics of aldehyde dehydrogenase 5a1 (succinate semialdehyde dehydrogenase and accumulation of gamma-hydroxybutyrate associated with its deficiency

    Directory of Open Access Journals (Sweden)

    Malaspina Patrizia

    2009-01-01

    Full Text Available Abstract Succinic semialdehyde dehydrogenase (SSADH; aldehyde dehydrogenase 5A1 [ALDH5A1]; locus 6p22 occupies a central position in central nervous system (CNS neurotransmitter metabolism as one of two enzymes necessary for γ-aminobutyric acid (GABA recycling from the synaptic cleft. Its importance is highlighted by the neurometabolic disease associated with its inherited deficiency in humans, as well as the severe epileptic phenotype observed in Aldh5a1-/- knockout mice. Expanding evidence now suggests, however, that even subtle decreases in human SSADH activity, associated with rare and common single nucleotide polymorphisms, may produce subclinical pathological effects. SSADH, in conjunction with aldo-keto reductase 7A2 (AKR7A2, represent two neural enzymes responsible for further catabolism of succinic semialdehyde, producing either succinate (SSADH or γ-hydroxybutyrate (GHB; AKR7A2. A GABA analogue, GHB is a short-chain fatty alcohol with unusual properties in the CNS and a long pharmacological history. Moreover, SSADH occupies a further role in the CNS as the enzyme responsible for further metabolism of the lipid peroxidation aldehyde 4-hydroxy-2-nonenal (4-HNE, an intermediate known to induce oxidant stress. Accordingly, subtle decreases in SSADH activity may have the capacity to lead to regional accumulation of neurotoxic intermediates (GHB, 4-HNE. Polymorphisms in SSADH gene structure may also associate with quantitative traits, including intelligence quotient and life expectancy. Further population-based studies of human SSADH activity promise to reveal additional properties of its function and additional roles in CNS tissue.

  15. 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)

    Science.gov (United States)

    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...

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

    DEFF Research Database (Denmark)

    Aziz, Ramy K.; Monk, Jonathan M.; Andrews, Kathleen A.

    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, whi...

  17. Genetic Polymorphisms of the Mitochondrial Aldehyde Dehydrogenase ALDH2 Gene in a Large Ethnic Hakka Population in Southern China.

    Science.gov (United States)

    Zhong, Zhixiong; Hou, Jingyuan; Li, Bin; Zhang, Qifeng; Li, Cunren; Liu, Zhidong; Yang, Min; Zhong, Wei; Zhao, Pingsen

    2018-04-06

    BACKGROUND Human mitochondrial aldehyde dehydrogenase 2 (ALDH2) plays a critical role in the detoxification of the ethanol metabolite acetaldehyde. The ALDH2*2 (rs671) gene variant is mainly absent among Europeans but is prevalent in populations in East Asia. The aim of this study was to investigate ALDH2*2 mutant alleles and genotype frequencies in the Hakka population of China. MATERIAL AND METHODS Between January 2016 and June 2017, 7,966 unrelated individuals were recruited into the study from the Hakka ethnic population residing in the Meizhou area of Guangdong Province, China, who provided venous blood samples. Genotyping of ALDH2 genotypes were determined using a gene chip platform and confirmed by DNA sequencing. RESULTS In the 7,966 individuals from the Hakka population of China in this study, the frequencies of the ALDH2 genotypes *1/*1, *1/*2 and *2/*2 were 52.03%, 39.67%, and 8.30%, respectively; 47.97% of the individuals were found to carry the ALDH2*2 genotype, which was associated with a deficiency in the aldehyde dehydrogenase (ALDH2) enzyme activity. The frequency of the ALDH2*2 allele was lower than that previously reported in the Japanese population but higher than that reported in other Oriental populations. CONCLUSIONS The findings of this study have provided new information on the ALDH2 gene polymorphisms in the Hakka ethnic population residing in the Meizhou area of Guangdong Province, China, including an understanding of the origin of the atypical ALDH2*2 allele. Also, the study findings may be relevant to the primary care of patients in China.

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

    Science.gov (United States)

    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.

  19. Glu504Lys Single Nucleotide Polymorphism of Aldehyde Dehydrogenase 2 Gene and the Risk of Human Diseases

    Directory of Open Access Journals (Sweden)

    Yan Zhao

    2015-01-01

    Full Text Available Aldehyde dehydrogenase (ALDH 2 is a mitochondrial enzyme that is known for its important role in oxidation and detoxification of ethanol metabolite acetaldehyde. ALDH2 also metabolizes other reactive aldehydes such as 4-hydroxy-2-nonenal and acrolein. The Glu504Lys single nucleotide polymorphism (SNP of ALDH2 gene, which is found in approximately 40% of the East Asian populations, causes defect in the enzyme activity of ALDH2, leading to alterations in acetaldehyde metabolism and alcohol-induced “flushing” syndrome. Evidence suggests that ALDH2 Glu504Lys SNP is a potential candidate genetic risk factor for a variety of chronic diseases such as cardiovascular disease, cancer, and late-onset Alzheimer’s disease. In addition, the association between ALDH2 Glu504Lys SNP and the development of these chronic diseases appears to be affected by the interaction between the SNP and lifestyle factors such as alcohol consumption as well as by the presence of other genetic variations.

  20. Human class I alcohol dehydrogenases catalyze the interconversion of alcohols and aldehydes in the metabolism of dopamine.

    Science.gov (United States)

    Mårdh, G; Vallee, B L

    1986-11-18

    The class I human liver alcohol dehydrogenases (ADHs) catalyze the interconversion of the intermediary alcohols and aldehydes of dopamine metabolism in vitro, whereas those of the class II and class III do not. The individual, homogeneous class I isozymes oxidize (3,4-dihydroxyphenyl)ethanol and (4-hydroxy-3-methoxyphenyl)ethanol (HMPE) and ethanol with kcat/Km values in the range from 16 to 240 mM-1 min-1 and from 16 to 66 mM-1 min-1, respectively. They reduce the corresponding dopamine aldehydes (3,4-dihydroxyphenyl)acetaldehyde and (4-hydroxy-3-methoxyphenyl)acetaldehyde (HMPAL) with kcat/Km values varying from 7800 to 190,000 mM-1 min-1, considerably more efficient than the reduction of acetaldehyde with kcat/Km values from 780 to 4900 mM-1 min-1. For beta 1 gamma 2 ADH, ethanol competes with HMPE oxidation with a Ki of 23 microM. In addition, 1,10-phenanthroline inhibits HMPE oxidation and HMPAL reduction with Ki values of 20 microM and 12 microM, respectively, both quite similar to that for ethanol, Ki = 22 microM. Thus, both ethanol/acetaldehyde and the dopamine intermediates compete for the same site of ADH, a basis for the ethanol-induced in vivo alterations of dopamine metabolism.

  1. Targeted therapy for a subset of acute myeloid leukemias that lack expression of aldehyde dehydrogenase 1A1.

    Science.gov (United States)

    Gasparetto, Maura; Pei, Shanshan; Minhajuddin, Mohammad; Khan, Nabilah; Pollyea, Daniel A; Myers, Jason R; Ashton, John M; Becker, Michael W; Vasiliou, Vasilis; Humphries, Keith R; Jordan, Craig T; Smith, Clayton A

    2017-06-01

    Aldehyde dehydrogenase 1A1 (ALDH1A1) activity is high in hematopoietic stem cells and functions in part to protect stem cells from reactive aldehydes and other toxic compounds. In contrast, we found that approximately 25% of all acute myeloid leukemias expressed low or undetectable levels of ALDH1A1 and that this ALDH1A1 - subset of leukemias correlates with good prognosis cytogenetics. ALDH1A1 - cell lines as well as primary leukemia cells were found to be sensitive to treatment with compounds that directly and indirectly generate toxic ALDH substrates including 4-hydroxynonenal and the clinically relevant compounds arsenic trioxide and 4-hydroperoxycyclophosphamide. In contrast, normal hematopoietic stem cells were relatively resistant to these compounds. Using a murine xenotransplant model to emulate a clinical treatment strategy, established ALDH1A1 - leukemias were also sensitive to in vivo treatment with cyclophosphamide combined with arsenic trioxide. These results demonstrate that targeting ALDH1A1 - leukemic cells with toxic ALDH1A1 substrates such as arsenic and cyclophosphamide may be a novel targeted therapeutic strategy for this subset of acute myeloid leukemias. Copyright© Ferrata Storti Foundation.

  2. Isolated tumoral pyruvate dehydrogenase can synthesize acetoin which inhibits pyruvate oxidation as well as other aldehydes.

    Science.gov (United States)

    Baggetto, L G; Lehninger, A L

    1987-05-29

    Oxidation of 1 mM pyruvate by Ehrlich and AS30-D tumor mitochondria is inhibited by acetoin, an unusual and important metabolite of pyruvate utilization by cancer cells, by acetaldehyde, methylglyoxal and excess pyruvate. The respiratory inhibition is reversed by other substrates added to pyruvate and also by 0.5 mM ATP. Kinetic properties of pyruvate dehydrogenase complex isolated from these tumor mitochondria have been studied. This complex appears to be able to synthesize acetoin from acetaldehyde plus pyruvate and is competitively inhibited by acetoin. The role of a new regulatory pattern for tumoral pyruvate dehydrogenase is presented.

  3. The ORF slr0091 of Synechocystis sp. PCC6803 encodes a high-light induced aldehyde dehydrogenase converting apocarotenals and alkanals

    KAUST Repository

    Trautmann, Danika

    2013-07-05

    Oxidative cleavage of carotenoids and peroxidation of lipids lead to apocarotenals and aliphatic aldehydes called alkanals, which react with vitally important compounds, promoting cytotoxicity. Although many enzymes have been reported to deactivate alkanals by converting them into fatty acids, little is known about the mechanisms used to detoxify apocarotenals or the enzymes acting on them. Cyanobacteria and other photosynthetic organisms must cope with both classes of aldehydes. Here we report that the Synechocystis enzyme SynAlh1, encoded by the ORF slr0091, is an aldehyde dehydrogenase that mediates oxidation of both apocarotenals and alkanals into the corresponding acids. Using a crude lysate of SynAlh1-expressing Escherichia coli cells, we show that SynAlh1 converts a wide range of apocarotenals and alkanals, with a preference for apocarotenals with defined chain lengths. As suggested by in vitro incubations and using engineered retinal-forming E. coli cells, we found that retinal is not a substrate for SynAlh1, making involvement in Synechocystis retinoid metabolism unlikely. The transcript level of SynAlh1 is induced by high light and cold treatment, indicating a role in the stress response, and the corresponding gene is a constituent of a stress-related operon. The assumptions regarding the function of SynAlh are further supported by the surprisingly high homology to human and plant aldehyde dehydrogenase that have been assigned to aldehyde detoxification. SynAlh1 is the first aldehyde dehydrogenase that has been shown to form both apocarotenoic and fatty acids. This dual function suggests that its eukaryotic homologs may also be involved in apocarotenal metabolism, a function that has not been considered so far. Aldehyde dehydrogenases play an important role in detoxification of reactive aldehydes. Here, we report on a cyanbacterial enzyme capable in converting two classes of lipid-derived aldehydes, apocaotenals and alkanals. The corresponding gene is a

  4. Aldehyde dehydrogenase 2*2 knock-in mice show increased reactive oxygen species production in response to cisplatin treatment.

    Science.gov (United States)

    Kim, Jeewon; Chen, Che-Hong; Yang, Jieying; Mochly-Rosen, Daria

    2017-05-22

    The aldehyde dehydrogenase (ALDH) enzyme family metabolizes and detoxifies both exogenous and endogenous aldehydes. Since chemotherapeutic agents, such as cisplatin, generate cytotoxic aldehydes and oxidative stress, and chemoresistant cancer cells express high levels of ALDH enzymes, we hypothesized that different ALDH expression within cells may show different chemosensitivity. ALDH2 has the lowest Km for acetaldehyde among ALDH isozymes and detoxifies acetaldehydes in addition to other reactive aldehydes, such as 4-hydroxy-nonenal, malondialdehyde and acrolein produced from lipid peroxidation by reactive oxygen species (ROS). Thus, cells with an ALDH2 variant may sensitize them to these ROS-inducing chemotherapy drugs. Here, we used wild type C57BL/6 mice and ALDH2*2 knock-in mutant mice and compared the basal level of ROS in different tissues. Then, we treated the mice with cisplatin, isolated cells from organs and fractionated them into lysates containing mitochondrial and cytosolic fractions, treated with cisplatin again in vitro, and compared the level of ROS generated. We show that overall ROS production increases with cisplatin treatment in cells with ALDH2 mutation. The treatment of cisplatin in the wild type mice did not change the level of ROS compared to PBS treated controls. In contrast, ALDH2*2 knock-in mutant mice showed a significantly increased level of ROS compared to wild type mice in tongue, lung, kidney and brain tissues without any treatment. ALDH2*2 mutant mice showed 20% of the ALDH2 activity in the kidney compared to wild type mice. Treatment of ALDH2*2 mutant mice with cisplatin showed increased ROS levels in the mitochondrial fraction of kidney. In the cytosolic fraction, treatment of mutant mice with cisplatin increased ROS levels in lung and brain compared to PBS treated controls. Furthermore, ALDH2*2 mutant mice treated with cisplatin showed increased cytotoxicity in the kidney cells compared to PBS treated mutant controls. These data

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  7. Alcohol and aldehyde dehydrogenase polymorphisms and risk for suicide: a preliminary observation in the Japanese male population.

    Science.gov (United States)

    Hishimoto, A; Fukutake, M; Mouri, K; Nagasaki, Y; Asano, M; Ueno, Y; Nishiguchi, N; Shirakawa, O

    2010-07-01

    Epidemiological studies have shown that excessive alcohol consumption is a potent risk factor to develop suicidal behavior. Genetic factors for suicidal behavior have been observed in family, twin, and adoption studies. Because alcohol dehydrogenase (ADH1B) His47Arg and mitochondrial aldehyde dehydrogenase (ALDH2) Glu487Lys single nucleotide polymorphisms (SNPs), which affect alcohol metabolism, have been reported to exert significant impacts on alcohol consumption and on the risk for alcoholism in East Asia populations, we explored associations of the two functional SNPs with suicide using a case-control study of 283 completed suicides and 319 control subjects in the Japanese population. We found that the inactive ALDH2 allele (487Lys) was significantly less frequent in the completed suicides (19.3%) than in the controls (29.3%), especially in males, whereas this was not the case in females. The males bearing alcoholism-susceptible homozygotes at both loci (inactive ADH1B Arg/Arg and active ALDH2 Glu/Glu genotypes) have a 10 times greater risk for suicide compared with the males bearing alcoholism-protective homozygotes at both loci. Our data show the genetic impact of the two polymorphisms on suicidal behavior in the Japanese population, especially in males. Because we did not verify the daily alcohol consumption, the association of these SNPs with suicide might be due to alcoholism itself. Further studies using case-control subjects, which verifies the details of current and past alcohol consumption and diagnosis for alcoholism, are required to confirm these findings.

  8. Direct electron transfer-based bioanodes for ethanol biofuel cells using PQQ-dependent alcohol and aldehyde dehydrogenases

    International Nuclear Information System (INIS)

    Aquino Neto, Sidney; Suda, Emily L.; Xu, Shuai; Meredith, Matthew T.; De Andrade, Adalgisa R.; Minteer, Shelley D.

    2013-01-01

    This paper compares the performance of a DET (direct electron transfer) bioanode containing both PQQ-ADH (pyrroloquinoline quinone-dependent alcohol dehydrogenase) and PQQ-AldDH (PQQ-dependent aldehyde dehydrogenase) immobilized onto different modified electrode surfaces employing either a tetrabutylammonium (TBAB)-modified Nafion ® membrane polymer or polyamidoamine (PAMAM) dendrimers for the enzyme immobilization. The electrochemical characterization showed that the prepared bioelectrodes were able to undergo DET onto glassy carbon surface in the presence as well as the absence of multi-walled carbon nanotubes (MWCNTs); also, in the latter case a relevant shift in the oxidation peak of about 180 mV vs. saturated calomel electrode (SCE) was observed. A very similar redox potential was achieved with the self-assembled bioelectrode prepared onto modified-gold surfaces with dendrimers, indicating that both methodologies provide an environment that enables the PQQ-enzymes to undergo DET. The biofuel cell tests confirmed the ease of the DET process and the enhanced performance in the presence of the carbon nanotubes. Considering the bioanodes prepared with PAMAM dendrimers, the power density values vary from 19.4 μW cm −2 without MWCNTs to 25.7 μW cm −2 in the presence of MWCNTs. Similarly, with the bioanodes prepared with the TBAB-modified-Nafion ® polymer, the results indicate power densities of 27.9 and 38.4 μW cm −2 respectively. These electrode modifications represent effective methods for immobilization and direct electrical connection of quinohemoproteins to electrode surfaces.

  9. The Short-Chain Alcohol Dehydrogenase ABA2 Catalyzes the Conversion of Xanthoxin to Abscisic AldehydeW⃞

    Science.gov (United States)

    González-Guzmán, Miguel; Apostolova, Nadezda; Bellés, José M.; Barrero, José M.; Piqueras, Pedro; Ponce, María R.; Micol, José L.; Serrano, Ramón; Rodríguez, Pedro L.

    2002-01-01

    Mutants able to germinate and perform early growth in medium containing a high NaCl concentration were identified during the course of two independent screenings and named salt resistant (sre) and salobreño (sañ). The sre and sañ mutants also were able to germinate in high-osmoticum medium, indicating that they are osmotolerant in a germination assay. Complementation analyses revealed that sre1-1, sre1-2, sañ3-1, and sañ3-2 were alleles of the abscisic acid (ABA) biosynthesis ABA2 gene. A map-based cloning strategy allowed the identification of the ABA2 gene and molecular characterization of four new aba2 alleles. The ABA2 gene product belongs to the family of short-chain dehydrogenases/reductases, which are known to be NAD- or NADP-dependent oxidoreductases. Recombinant ABA2 protein produced in Escherichia coli exhibits a Km value for xanthoxin of 19 μM and catalyzes in a NAD-dependent manner the conversion of xanthoxin to abscisic aldehyde, as determined by HPLC–mass spectrometry. The ABA2 mRNA is expressed constitutively in all plant organs examined and is not upregulated in response to osmotic stress. The results of this work are discussed in the context of previous genetic and biochemical evidence regarding ABA biosynthesis, confirming the xanthoxin→abscisic aldehyde→ABA transition as the last steps of the major ABA biosynthetic pathway. PMID:12172025

  10. The correlation between aldehyde dehydrogenase-1A1 level and tumor shrinkage after preoperative chemoradiation in locally advanced rectal cancer

    Directory of Open Access Journals (Sweden)

    Rhandyka Rafli

    2015-12-01

    Full Text Available This study was performed to determine the correlation between aldehyde dehydrogenase-1A1 (ALDH1A1 level and tumor shrinkage after chemoradiation in locally advanced rectal cancer. This is a retrospective study of 14 locally advanced rectal cancer patients with long course neoadjuvant chemoradiation. ALDH1A1 level was measured using ELISA from paraffin embedded tissue. Tumor shrinkage was measured from computed tomography (CT scan or magnetic resonance imaging (MRI based on Response Evaluation Criteria in Solid Tumor v1.1 (RECIST v1.1. The mean of ALDH1A1 level was 9.014 ± 3.3 pg/mL and the mean of tumor shrinkage was 7.89 ± 35.7%. Partial response proportion was 28.6%, stable disease proportion was 50% and progressive disease proportion was 21.4%. There was a significant strong negative correlation (r = –0.890, plt; 0.001 between ALDH1A1 and tumor shrinkage. In conclusion, tumor shrinkage in locally advanced rectal cancer after preoperative chemoradiation was influenced by ALDH1A1 level. Higher level of ALDH1A1 suggests decreased tumor shrinkage after preoperative chemoradiation.

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

    Science.gov (United States)

    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

  12. Disruption of the coenzyme binding site and dimer interface revealed in the crystal structure of mitochondrial aldehyde dehydrogenase "Asian" variant.

    Science.gov (United States)

    Larson, Heather N; Weiner, Henry; Hurley, Thomas D

    2005-08-26

    Mitochondrial aldehyde dehydrogenase (ALDH2) is the major enzyme that oxidizes ethanol-derived acetaldehyde. A nearly inactive form of the enzyme, ALDH2*2, is found in about 40% of the East Asian population. This variant enzyme is defined by a glutamate to lysine substitution at residue 487 located within the oligomerization domain. ALDH2*2 has an increased Km for its coenzyme, NAD+, and a decreased kcat, which lead to low activity in vivo. Here we report the 2.1 A crystal structure of ALDH2*2. The structure shows a large disordered region located at the dimer interface that includes much of the coenzyme binding cleft and a loop of residues that form the base of the active site. As a consequence of these structural changes, the variant enzyme exhibits rigid body rotations of its catalytic and coenzyme-binding domains relative to the oligomerization domain. These structural perturbations are the direct result of the inability of lysine 487 to form important stabilizing hydrogen bonds with arginines 264 and 475. Thus, the elevated Km for coenzyme exhibited by this variant probably reflects the energetic penalty for reestablishing this site for productive coenzyme binding, whereas the structural alterations near the active site are consistent with the lowered Vmax.

  13. The aldehyde dehydrogenase 2 polymorphisms on neuropsychological performance in bipolar II disorder with or without comorbid anxiety disorder.

    Science.gov (United States)

    Lu, Ru-Band; Chang, Yun-Hsuan; Wang, Tzu-Yun; Lee, Sheng-Yu; Chen, Po See; Yang, Yen Kuang

    2018-01-01

    Anxiety disorders (ADs), the most common comorbid illnesses with bipolar disorder (BP) has been reported to associate with dopamine system. Dopamine, metabolized to 3,4-dihydroxyphenylacetic acid (DOPAC) by aldehyde dehydrogenase 2 (ALDH2), and the distribution of the ALDH2*1/*1, and ALDH2*1/*2+ALDH*2/*2 alleles in the Han Chinese general population is relatively equal. The association between dopamine metabolic enzymes and cognitive performance in patients with bipolar II disorder (BP-II) comorbid with AD is unclear. This study proposed to explore the role of ALDH2 polymorphisms on neuropsychological performance between BP-II comorbid with or without AD. One hundred ninety-seven BP-II patients with and without a comorbid AD were recruited and compared with 130 healthy controls (HCs). A polymerase chain reaction and a restriction fragment length polymorphism analysis were used to determine genotypes for ALDH2, and study participants underwent neuropsychological tests. An interaction between AD comorbidity and the ALDH2 polymorphisms was found in different domain of cognitive dysfunction in the BP-II patients. The ALDH2 polymorphisms might have different effects on the neuropsychological performance of BP-II patients with and without comorbid AD.

  14. The expression of aldehyde dehydrogenase 1 (ALDH1) in ovarian carcinomas and its clinicopathological associations: a retrospective study

    International Nuclear Information System (INIS)

    Huang, Ruixia; Li, Xiaoran; Holm, Ruth; Trope, Claes G.; Nesland, Jahn M.; Suo, Zhenhe

    2015-01-01

    Aldehyde dehydrogenase 1 (ALDH1) is widely used as a specific cancer stem cell marker in a variety of cancers, and may become a promising target for cancer therapy. However, the role of its expression in tumor cells and the microenvironment in different cancers is still controversial. To clarify the clinicopathological effect of ALDH1 expression in ovarian carcinoma, a series of 248 cases of paraffin-embedded formalin fixed ovarian carcinoma tissues with long term follow-up information were studied by immunohistochemistry. The immunostaining of ALDH1was variably detected in both tumor cells and the stromal cells, although the staining in tumor cells was not as strong as that in stromal cells. Statistical analyses showed that high ALDH1 expression in tumor cells was significantly associated with histological subtypes, early FIGO stage, well differentiation grade and better survival probability (p < 0.05). The expression of ALDH1 in the stromal cells had no clinicopathological associations in the present study (p > 0.05). High expression of cancer stem cell marker ALDH1 in ovarian carcinoma cells may thus portend a favorable prognosis, but its expression in tumor microenvironment may have no role in tumor behavior of ovarian carcinomas. More studies are warranted to find out the mechanisms for this

  15. Ovarian cancer stem cells are enriched in side population and aldehyde dehydrogenase bright overlapping population.

    Directory of Open Access Journals (Sweden)

    Kazuyo Yasuda

    Full Text Available Cancer stem-like cells (CSCs/cancer-initiaiting cells (CICs are defined as a small population of cancer cells that have self-renewal capacity, differentiation potential and high tumor-initiating ability. CSCs/CICs of ovarian cancer have been isolated by side population (SP analysis, ALDEFLUOR assay and using cell surface markers. However, these approaches are not definitive markers for CSCs/CICs, and it is necessary to refine recent methods for identifying more highly purified CSCs/CICs. In this study, we analyzed SP cells and aldehyde dehydrogenese bright (ALDH(Br cells from ovarian cancer cells. Both SP cells and ALDH(Br cells exhibited higher tumor-initiating ability and higher expression level of a stem cell marker, sex determining region Y-box 2 (SOX2, than those of main population (MP cells and ALDH(Low cells, respectively. We analyzed an SP and ALDH(Br overlapping population (SP/ALDH(Br, and the SP/ALDH(Br population exhibited higher tumor-initiating ability than that of SP cells or ALDH(Br cells, enabling initiation of tumor with as few as 10(2 cells. Furthermore, SP/ADLH(Br population showed higher sphere-forming ability, cisplatin resistance, adipocyte differentiation ability and expression of SOX2 than those of SP/ALDH(Low, MP/ALDH(Br and MP/ALDH(Low cells. Gene knockdown of SOX2 suppressed the tumor-initiation of ovarian cancer cells. An SP/ALDH(Br population was detected in several gynecological cancer cells with ratios of 0.1% for HEC-1 endometrioid adenocarcinoma cells to 1% for MCAS ovary mucinous adenocarcinoma cells. Taken together, use of the SP and ALDH(Br overlapping population is a promising approach to isolate highly purified CSCs/CICs and SOX2 might be a novel functional marker for ovarian CSCs/CICs.

  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.

    Directory of Open Access Journals (Sweden)

    Akira Yokoyama

    Full Text Available 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. JWH-018 ω-OH, a shared hydroxy metabolite of the two synthetic cannabinoids JWH-018 and AM-2201, undergoes oxidation by alcohol dehydrogenase and aldehyde dehydrogenase enzymes in vitro forming the carboxylic acid metabolite

    DEFF Research Database (Denmark)

    Holm, Niels Bjerre; Noble, Carolina; Linnet, Kristian

    2016-01-01

    +)-dependent alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) enzymes. The sole end-product identified in HLC was the JWH-018 ω-COOH metabolite, while trapping tests with methoxyamine proved the presence of the aldehyde intermediate. ADH/ALDH and UDP-glucuronosyl-transferases (UGT) enzymes may therefore...... microsomal (HLM) incubations raising the possibility that the discrepancy is due to involvement of cytosolic enzymes. Here we demonstrate in incubations with human liver cytosol (HLC), that JWH-018 ω-OH, but not the JWH-018 parent compound, is a substrate for nicotinamide adenine dinucleotide (NAD...... catalyzed by non-CYP enzyme(s). The pathway presented here may therefore be especially important for N-(5-fluoropentyl) substituted synthetic cannabinoids, because the oxidative defluorination can occur even if the CYP-mediated metabolism preferentially takes place on other parts of the molecule than the N...

  18. Genome-wide characterization of the aldehyde dehydrogenase gene superfamily in soybean and its potential role in drought stress response.

    Science.gov (United States)

    Wang, Wei; Jiang, Wei; Liu, Juge; Li, Yang; Gai, Junyi; Li, Yan

    2017-07-07

    Aldehyde dehydrogenases (ALDHs) represent a group of enzymes that detoxify aldehydes by facilitating their oxidation to carboxylic acids, and have been shown to play roles in plant response to abiotic stresses. However, the comprehensive analysis of ALDH superfamily in soybean (Glycine max) has been limited. In present study, a total of 53 GmALDHs were identified in soybean, and grouped into 10 ALDH families according to the ALDH Gene Nomenclature Committee and phylogenetic analysis. These groupings were supported by their gene structures and conserved motifs. Soybean ALDH superfamily expanded mainly by whole genome duplication/segmental duplications. Gene network analysis identified 1146 putative co-functional genes of 51 GmALDHs. Gene Ontology (GO) enrichment analysis suggested the co-functional genes of these 51 GmALDHs were enriched (FDR soybean tissues. The expression levels of 13 GmALDHs were significantly up-regulated and 14 down-regulated in response to water deficit. The occurrence frequencies of three drought-responsive cis-elements (ABRE, CRT/DRE, and GTGCnTGC/G) were compared in GmALDH genes that were up-, down-, or non-regulated by water deficit. Higher frequency of these three cis-elements was observed for the group of up-regulated GmALDH genes as compared to the group of down- or non- regulated GmALDHs by drought stress, implying their potential roles in the regulation of soybean response to drought stress. A total of 53 ALDH genes were identified in soybean genome and their phylogenetic relationships and duplication patterns were analyzed. The potential functions of GmALDHs were predicted by analyses of their co-functional gene networks, gene expression profiles, and cis-regulatory elements. Three GmALDH genes, including GmALDH3H2, GmALDH12A2 and GmALDH18B3, were highly induced by drought stress in soybean leaves. Our study provides a foundation for future investigations of GmALDH gene function in soybean.

  19. Improved tolerance to various abiotic stresses in transgenic sweet potato (Ipomoea batatas) expressing spinach betaine aldehyde dehydrogenase.

    Science.gov (United States)

    Fan, Weijuan; Zhang, Min; Zhang, Hongxia; Zhang, Peng

    2012-01-01

    Abiotic stresses are critical delimiters for the increased productivity and cultivation expansion of sweet potato (Ipomoea batatas), a root crop with worldwide importance. The increased production of glycine betaine (GB) improves plant tolerance to various abiotic stresses without strong phenotypic changes, providing a feasible approach to improve stable yield production under unfavorable conditions. The gene encoding betaine aldehyde dehydrogenase (BADH) is involved in the biosynthesis of GB in plants, and the accumulation of GB by the heterologous overexpression of BADH improves abiotic stress tolerance in plants. This study is to improve sweet potato, a GB accumulator, resistant to multiple abiotic stresses by promoted GB biosynthesis. A chloroplastic BADH gene from Spinacia oleracea (SoBADH) was introduced into the sweet potato cultivar Sushu-2 via Agrobacterium-mediated transformation. The overexpression of SoBADH in the transgenic sweet potato improved tolerance to various abiotic stresses, including salt, oxidative stress, and low temperature. The increased BADH activity and GB accumulation in the transgenic plant lines under normal and multiple environmental stresses resulted in increased protection against cell damage through the maintenance of cell membrane integrity, stronger photosynthetic activity, reduced reactive oxygen species (ROS) production, and induction or activation of ROS scavenging by the increased activity of free radical-scavenging enzymes. The increased proline accumulation and systemic upregulation of many ROS-scavenging genes in stress-treated transgenic plants also indicated that GB accumulation might stimulate the ROS-scavenging system and proline biosynthesis via an integrative mechanism. This study demonstrates that the enhancement of GB biosynthesis in sweet potato is an effective and feasible approach to improve its tolerance to multiple abiotic stresses without causing phenotypic defects. This strategy for trait improvement in

  20. Immunohistochemical analysis of aldehyde dehydrogenase isoforms and their association with estrogen-receptor status and disease progression in breast cancer

    Directory of Open Access Journals (Sweden)

    Opdenaker LM

    2014-12-01

    Full Text Available Lynn M Opdenaker,1,2 Kimberly M Arnold,1,3 Ryan T Pohlig,3,4 Jayasree S Padmanabhan,1 Daniel C Flynn,1,3 Jennifer Sims-Mourtada1–3 1Center for Translational Cancer Research, Helen F Graham Cancer Center, Christiana Care Health Services, Inc., Newark, Delaware, USA; 2Department of Biological Sciences, 3Department of Medical Laboratory Sciences, 4Biostatistics Core Facility, University of Delaware, Newark, Delaware, USA Abstract: In many types of tumors, especially breast tumors, aldehyde dehydrogenase (ALDH activity has been used to identify cancer stem-like cells within the tumor. The presence and quantity of these cells are believed to predict the response of tumors to chemotherapy. Therefore, identification and eradication of these cells would be necessary to cure the patient. However, there are 19 different ALDH isoforms that could contribute to the enzyme activity. ALDH1A1 and ALDH1A3 are among the isoforms mostly responsible for the increased ALDH activity observed in these stem-like cells, although the main isoforms vary in different tissues and tumor types. In the study reported here, we attempted to determine if ALDH1A1 or ALDH1A3, specifically, correlate with tumor stage, grade, and hormone-receptor status in breast-cancer patients. While there was no significant correlation between ALDH1A1 and any of the parameters tested, we were able to identify a positive correlation between ALDH1A3 and tumor stage in triple-negative cancers. In addition, ALDH1A3 was negatively correlated with estrogen-receptor status. Our data suggest that ALDH1A3 could be utilized as a marker to identify stem-like cells within triple-negative tumors. Keywords: breast tumor, ALDH, ALDH1A1, ALDH1A3, stem-like cells, triple-negative cancer

  1. Plastid-expressed betaine aldehyde dehydrogenase gene in carrot cultured cells, roots, and leaves confers enhanced salt tolerance.

    Science.gov (United States)

    Kumar, Shashi; Dhingra, Amit; Daniell, Henry

    2004-09-01

    Salinity is one of the major factors that limits geographical distribution of plants and adversely affects crop productivity and quality. We report here high-level expression of betaine aldehyde dehydrogenase (BADH) in cultured cells, roots, and leaves of carrot (Daucus carota) via plastid genetic engineering. Homoplasmic transgenic plants exhibiting high levels of salt tolerance were regenerated from bombarded cell cultures via somatic embryogenesis. Transformation efficiency of carrot somatic embryos was very high, with one transgenic event per approximately seven bombarded plates under optimal conditions. In vitro transgenic carrot cells transformed with the badh transgene were visually green in color when compared to untransformed carrot cells, and this offered a visual selection for transgenic lines. BADH enzyme activity was enhanced 8-fold in transgenic carrot cell cultures, grew 7-fold more, and accumulated 50- to 54-fold more betaine (93-101 micromol g(-1) dry weight of beta-Ala betaine and Gly betaine) than untransformed cells grown in liquid medium containing 100 mm NaCl. Transgenic carrot plants expressing BADH grew in the presence of high concentrations of NaCl (up to 400 mm), the highest level of salt tolerance reported so far among genetically modified crop plants. BADH expression was 74.8% in non-green edible parts (carrots) containing chromoplasts, and 53% in proplastids of cultured cells when compared to chloroplasts (100%) in leaves. Demonstration of plastid transformation via somatic embryogenesis utilizing non-green tissues as recipients of foreign DNA for the first time overcomes two of the major obstacles in extending this technology to important crop plants.

  2. Is aldehyde dehydrogenase 2 a credible genetic instrument for alcohol use in Mendelian randomization analysis in Southern Chinese men?

    Science.gov (United States)

    Au Yeung, Shiu Lun; Jiang, ChaoQiang; Cheng, Kar Keung; Liu, Bin; Zhang, WeiSen; Lam, Tai Hing; Leung, Gabriel M; Schooling, C Mary

    2013-02-01

    Mendelian randomization studies provide a means of assessing causal relations without interventions, but require valid genetic instruments. We assessed the credibility of aldehyde dehydrogenase 2 (ALDH2) as a genetic instrument for alcohol use in Southern Chinese men. We genotyped the single nucleotide polymorphism rs671 of ALDH2 in 4867 men from the Guangzhou Biobank Cohort Study. We used linear regression to assess the strength of the association of ALDH2 variants with alcohol use, whether ALDH2 variants were independently associated with socio-economic position or other potential confounders and whether associations of ALDH2 variants with cardiovascular risk factors (systolic and diastolic blood pressure, HDL- and LDL-cholesterol, fasting glucose), triglycerides, body mass index, self reported cardiovascular disease, self-reported ischaemic heart disease, cognitive function (delayed 10-word recall and Mini Mental State Examination score) and liver function (alanine transaminase and aspartate transaminase) were fully mediated by alcohol use. The minor allele frequency (A) of ALDH2 was 0.29. The F statistic for ALDH2 variants was 75.0, suggesting that substantial weak instrument bias is unlikely. ALDH2 variants were not associated with socio-economic position, smoking or physical activity. ALDH2 variants were only associated with diastolic blood pressure and HDL-cholesterol, but these genetic associations with blood pressure and HDL-cholesterol were attenuated after adjusting for alcohol use, suggesting the apparent genetic associations were possibly mediated by alcohol use. ALDH2 variants are a credible genetic instrument for Mendelian randomization studies of alcohol use and many attributes of health in Southern Chinese men.

  3. Improved Tolerance to Various Abiotic Stresses in Transgenic Sweet Potato (Ipomoea batatas) Expressing Spinach Betaine Aldehyde Dehydrogenase

    Science.gov (United States)

    Fan, Weijuan; Zhang, Min; Zhang, Hongxia; Zhang, Peng

    2012-01-01

    Abiotic stresses are critical delimiters for the increased productivity and cultivation expansion of sweet potato (Ipomoea batatas), a root crop with worldwide importance. The increased production of glycine betaine (GB) improves plant tolerance to various abiotic stresses without strong phenotypic changes, providing a feasible approach to improve stable yield production under unfavorable conditions. The gene encoding betaine aldehyde dehydrogenase (BADH) is involved in the biosynthesis of GB in plants, and the accumulation of GB by the heterologous overexpression of BADH improves abiotic stress tolerance in plants. This study is to improve sweet potato, a GB accumulator, resistant to multiple abiotic stresses by promoted GB biosynthesis. A chloroplastic BADH gene from Spinacia oleracea (SoBADH) was introduced into the sweet potato cultivar Sushu-2 via Agrobacterium-mediated transformation. The overexpression of SoBADH in the transgenic sweet potato improved tolerance to various abiotic stresses, including salt, oxidative stress, and low temperature. The increased BADH activity and GB accumulation in the transgenic plant lines under normal and multiple environmental stresses resulted in increased protection against cell damage through the maintenance of cell membrane integrity, stronger photosynthetic activity, reduced reactive oxygen species (ROS) production, and induction or activation of ROS scavenging by the increased activity of free radical-scavenging enzymes. The increased proline accumulation and systemic upregulation of many ROS-scavenging genes in stress-treated transgenic plants also indicated that GB accumulation might stimulate the ROS-scavenging system and proline biosynthesis via an integrative mechanism. This study demonstrates that the enhancement of GB biosynthesis in sweet potato is an effective and feasible approach to improve its tolerance to multiple abiotic stresses without causing phenotypic defects. This strategy for trait improvement in

  4. Inhibition of telomerase activity preferentially targets aldehyde dehydrogenase-positive cancer stem-like cells in lung cancer

    Directory of Open Access Journals (Sweden)

    Iniesta Pilar

    2011-08-01

    Full Text Available Abstract Background Mortality rates for advanced lung cancer have not declined for decades, even with the implementation of novel chemotherapeutic regimens or the use of tyrosine kinase inhibitors. Cancer Stem Cells (CSCs are thought to be responsible for resistance to chemo/radiotherapy. Therefore, targeting CSCs with novel compounds may be an effective approach to reduce lung tumor growth and metastasis. We have isolated and characterized CSCs from non-small cell lung cancer (NSCLC cell lines and measured their telomerase activity, telomere length, and sensitivity to the novel telomerase inhibitor MST312. Results The aldehyde dehydrogenase (ALDH positive lung cancer cell fraction is enriched in markers of stemness and endowed with stem cell properties. ALDH+ CSCs display longer telomeres than the non-CSC population. Interestingly, MST312 has a strong antiproliferative effect on lung CSCs and induces p21, p27 and apoptosis in the whole tumor population. MST312 acts through activation of the ATM/pH2AX DNA damage pathway (short-term effect and through decrease in telomere length (long-term effect. Administration of this telomerase inhibitor (40 mg/kg in the H460 xenograft model results in significant tumor shrinkage (70% reduction, compared to controls. Combination therapy consisting of irradiation (10Gy plus administration of MST312 did not improve the therapeutic efficacy of the telomerase inhibitor alone. Treatment with MST312 reduces significantly the number of ALDH+ CSCs and their telomeric length in vivo. Conclusions We conclude that antitelomeric therapy using MST312 mainly targets lung CSCs and may represent a novel approach for effective treatment of lung cancer.

  5. Improved tolerance to various abiotic stresses in transgenic sweet potato (Ipomoea batatas expressing spinach betaine aldehyde dehydrogenase.

    Directory of Open Access Journals (Sweden)

    Weijuan Fan

    Full Text Available Abiotic stresses are critical delimiters for the increased productivity and cultivation expansion of sweet potato (Ipomoea batatas, a root crop with worldwide importance. The increased production of glycine betaine (GB improves plant tolerance to various abiotic stresses without strong phenotypic changes, providing a feasible approach to improve stable yield production under unfavorable conditions. The gene encoding betaine aldehyde dehydrogenase (BADH is involved in the biosynthesis of GB in plants, and the accumulation of GB by the heterologous overexpression of BADH improves abiotic stress tolerance in plants. This study is to improve sweet potato, a GB accumulator, resistant to multiple abiotic stresses by promoted GB biosynthesis. A chloroplastic BADH gene from Spinacia oleracea (SoBADH was introduced into the sweet potato cultivar Sushu-2 via Agrobacterium-mediated transformation. The overexpression of SoBADH in the transgenic sweet potato improved tolerance to various abiotic stresses, including salt, oxidative stress, and low temperature. The increased BADH activity and GB accumulation in the transgenic plant lines under normal and multiple environmental stresses resulted in increased protection against cell damage through the maintenance of cell membrane integrity, stronger photosynthetic activity, reduced reactive oxygen species (ROS production, and induction or activation of ROS scavenging by the increased activity of free radical-scavenging enzymes. The increased proline accumulation and systemic upregulation of many ROS-scavenging genes in stress-treated transgenic plants also indicated that GB accumulation might stimulate the ROS-scavenging system and proline biosynthesis via an integrative mechanism. This study demonstrates that the enhancement of GB biosynthesis in sweet potato is an effective and feasible approach to improve its tolerance to multiple abiotic stresses without causing phenotypic defects. This strategy for trait

  6. Structures of Proline Utilization A (PutA) Reveal the Fold and Functions of the Aldehyde Dehydrogenase Superfamily Domain of Unknown Function*

    Science.gov (United States)

    Luo, Min; Gamage, Thameesha T.; Arentson, Benjamin W.; Schlasner, Katherine N.; Becker, Donald F.; Tanner, John J.

    2016-01-01

    Aldehyde dehydrogenases (ALDHs) catalyze the NAD(P)+-dependent oxidation of aldehydes to carboxylic acids and are important for metabolism and detoxification. Although the ALDH superfamily fold is well established, some ALDHs contain an uncharacterized domain of unknown function (DUF) near the C terminus of the polypeptide chain. Herein, we report the first structure of a protein containing the ALDH superfamily DUF. Proline utilization A from Sinorhizobium meliloti (SmPutA) is a 1233-residue bifunctional enzyme that contains the DUF in addition to proline dehydrogenase and l-glutamate-γ-semialdehyde dehydrogenase catalytic modules. Structures of SmPutA with a proline analog bound to the proline dehydrogenase site and NAD+ bound to the ALDH site were determined in two space groups at 1.7–1.9 Å resolution. The DUF consists of a Rossmann dinucleotide-binding fold fused to a three-stranded β-flap. The Rossmann domain resembles the classic ALDH superfamily NAD+-binding domain, whereas the flap is strikingly similar to the ALDH superfamily dimerization domain. Paradoxically, neither structural element performs its implied function. Electron density maps show that NAD+ does not bind to the DUF Rossmann fold, and small-angle X-ray scattering reveals a novel dimer that has never been seen in the ALDH superfamily. The structure suggests that the DUF is an adapter domain that stabilizes the aldehyde substrate binding loop and seals the substrate-channeling tunnel via tertiary structural interactions that mimic the quaternary structural interactions found in non-DUF PutAs. Kinetic data for SmPutA indicate a substrate-channeling mechanism, in agreement with previous studies of other PutAs. PMID:27679491

  7. Structures of Proline Utilization A (PutA) Reveal the Fold and Functions of the Aldehyde Dehydrogenase Superfamily Domain of Unknown Function.

    Science.gov (United States)

    Luo, Min; Gamage, Thameesha T; Arentson, Benjamin W; Schlasner, Katherine N; Becker, Donald F; Tanner, John J

    2016-11-11

    Aldehyde dehydrogenases (ALDHs) catalyze the NAD(P) + -dependent oxidation of aldehydes to carboxylic acids and are important for metabolism and detoxification. Although the ALDH superfamily fold is well established, some ALDHs contain an uncharacterized domain of unknown function (DUF) near the C terminus of the polypeptide chain. Herein, we report the first structure of a protein containing the ALDH superfamily DUF. Proline utilization A from Sinorhizobium meliloti (SmPutA) is a 1233-residue bifunctional enzyme that contains the DUF in addition to proline dehydrogenase and l-glutamate-γ-semialdehyde dehydrogenase catalytic modules. Structures of SmPutA with a proline analog bound to the proline dehydrogenase site and NAD + bound to the ALDH site were determined in two space groups at 1.7-1.9 Å resolution. The DUF consists of a Rossmann dinucleotide-binding fold fused to a three-stranded β-flap. The Rossmann domain resembles the classic ALDH superfamily NAD + -binding domain, whereas the flap is strikingly similar to the ALDH superfamily dimerization domain. Paradoxically, neither structural element performs its implied function. Electron density maps show that NAD + does not bind to the DUF Rossmann fold, and small-angle X-ray scattering reveals a novel dimer that has never been seen in the ALDH superfamily. The structure suggests that the DUF is an adapter domain that stabilizes the aldehyde substrate binding loop and seals the substrate-channeling tunnel via tertiary structural interactions that mimic the quaternary structural interactions found in non-DUF PutAs. Kinetic data for SmPutA indicate a substrate-channeling mechanism, in agreement with previous studies of other PutAs. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Saúl Gómez-Manzo

    2015-01-01

    Full Text Available 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.

  10. aldB, an RpoS-dependent gene in Escherichia coli encoding an aldehyde dehydrogenase that is repressed by Fis and activated by Crp.

    Science.gov (United States)

    Xu, J; Johnson, R C

    1995-06-01

    Escherichia coli aldB was identified as a gene that is negatively regulated by Fis but positively regulated by RpoS. The complete DNA sequence determined in this study indicates that aldB encodes a 56.3-kDa protein which shares a high degree of homology with an acetaldehyde dehydrogenase encoded by acoD of Alcaligenes eutrophus and an aldehyde dehydrogenase encoded by aldA of Vibrio cholerae and significant homology with a group of other aldehyde dehydrogenases from prokaryotes and eukaryotes. Expression of aldB is maximally induced during the transition from exponential phase to stationary phase. Its message levels are elevated three- to fourfold by a fis mutation and abolished by an rpoS mutation. In addition, the expression of an aldB-lacZ fusion was decreased about 20-fold in the absence of crp. DNase I footprinting analysis showed that five Fis binding sites and one Crp binding site are located within the aldB promoter region, suggesting that Fis and Crp are acting directly to control aldB transcription. AldB expression is induced by ethanol, but in contrast to that of most of the RpoS-dependent genes, the expression of aldB is not altered by an increase in medium osmolarity.

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

    Science.gov (United States)

    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

  12. Identification and Overexpression of a Bifunctional Aldehyde/Alcohol Dehydrogenase Responsible for Ethanol Production in Thermoanaerobacter mathranii

    DEFF Research Database (Denmark)

    Yao, Shuo; Just Mikkelsen, Marie

    2010-01-01

    Thermoanaerobacter mathranii contains four genes, adhA, adhB, bdhA and adhE, predicted to code for alcohol dehydrogenases involved in ethanol metabolism. These alcohol dehydrogenases were characterized as NADP(H)-dependent primary alcohol dehydrogenase (AdhA), secondary alcohol dehydrogenase (Adh....... Overexpressions of AdhE in strain BG1E1 with xylose as a substrate facilitate the production of ethanol at an increased yield. Copyright © 2010 S. Karger AG, Basel...

  13. Differences in the roles of conserved glutamic acid residues in the active site of human class 3 and class 2 aldehyde dehydrogenases.

    Science.gov (United States)

    Mann, C J; Weiner, H

    1999-10-01

    Although the three-dimensional structure of the dimeric class 3 rat aldehyde dehydrogenase has recently been published (Liu ZJ et al., 1997, Nature Struct Biol 4:317-326), few mechanistic studies have been conducted on this isoenzyme. We have characterized the enzymatic properties of recombinant class 3 human stomach aldehyde dehydrogenase, which is very similar in amino acid sequence to the class 3 rat aldehyde dehydrogenase. We have determined that the rate-limiting step for the human class 3 isozyme is hydride transfer rather than deacylation as observed for the human liver class 2 mitochondrial enzyme. No enhancement of NADH fluorescence was observed upon binding to the class 3 enzyme, while fluorescence enhancement of NADH has been previously observed upon binding to the class 2 isoenzyme. It was also observed that binding of the NAD cofactor inhibited the esterase activity of the class 3 enzyme while activating the esterase activity of the class 2 enzyme. Site-directed mutagenesis of two conserved glutamic acid residues (209 and 333) to glutamine residues indicated that, unlike in the class 2 enzyme, Glu333 served as the general base in the catalytic reaction and E209Q had only marginal effects on enzyme activity, thus confirming the proposed mechanism (Hempel J et al., 1999, Adv Exp Med Biol 436:53-59). Together, these data suggest that even though the subunit structures and active site residues of the isozymes are similar, the enzymes have very distinct properties besides their oligomeric state (dimer vs. tetramer) and substrate specificity.

  14. The mutation in the mitochondrial aldehyde dehydrogenase (ALDH2) gene responsible for alcohol-induced flushing increases turnover of the enzyme tetramers in a dominant fashion.

    OpenAIRE

    Xiao, Q; Weiner, H; Crabb, D W

    1996-01-01

    Deficiency in mitochondrial aldehyde dehydrogenase (ALDH2), a tetrameric enzyme, results from inheriting one or two ALDH2*2 alleles. This allele encodes a protein subunit with a lysine for glutamate substitution at position 487 and is dominant over the wild-type allele, ALDH2*1. The ALDH2*2-encoded subunit (ALDH2K) reduces the activity of ALDH2 enzyme in cell lines expressing the wild-type subunit (ALDH2E). In addition to this effect on the enzyme activity, we now report that ALDH2*2 heterozy...

  15. Malignant phyllodes tumors display mesenchymal stem cell features and aldehyde dehydrogenase/disialoganglioside identify their tumor stem cells.

    Science.gov (United States)

    Lin, Jin-Jin; Huang, Chiun-Sheng; Yu, John; Liao, Guo-Shiou; Lien, Huang-Chun; Hung, Jung-Tung; Lin, Ruey-Jen; Chou, Fen-Pi; Yeh, Kun-Tu; Yu, Alice L

    2014-03-26

    Although breast phyllodes tumors are rare, there is no effective therapy other than surgery. Little is known about their tumor biology. A malignant phyllodes tumor contains heterologous stromal elements, and can transform into rhabdomyosarcoma, liposarcoma and osteosarcoma. These versatile properties prompted us to explore their possible relationship to mesenchymal stem cells (MSCs) and to search for the presence of cancer stem cells (CSCs) in phyllodes tumors. Paraffin sections of malignant phyllodes tumors were examined for various markers by immunohistochemical staining. Xenografts of human primary phyllodes tumors were established by injecting freshly isolated tumor cells into the mammary fat pad of non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice. To search for CSCs, xenografted tumor cells were sorted into various subpopulations by flow cytometry and examined for their in vitro mammosphere forming capacity, in vivo tumorigenicity in NOD-SCID mice and their ability to undergo differentiation. Immunohistochemical analysis revealed the expression of the following 10 markers: CD44, CD29, CD106, CD166, CD105, CD90, disialoganglioside (GD2), CD117, Aldehyde dehydrogenase 1 (ALDH), and Oct-4, and 7 clinically relevant markers (CD10, CD34, p53, p63, Ki-67, Bcl-2, vimentin, and Globo H) in all 51 malignant phyllodes tumors examined, albeit to different extents. Four xenografts were successfully established from human primary phyllodes tumors. In vitro, ALDH+ cells sorted from xenografts displayed approximately 10-fold greater mammosphere-forming capacity than ALDH- cells. GD2+ cells showed a 3.9-fold greater capacity than GD2- cells. ALDH+/GD2+cells displayed 12.8-fold greater mammosphere forming ability than ALDH-/GD2- cells. In vivo, the tumor-initiating frequency of ALDH+/GD2+ cells were up to 33-fold higher than that of ALDH+ cells, with as few as 50 ALDH+/GD2+ cells being sufficient for engraftment. Moreover, we provided the first evidence for

  16. Evidence that the C-terminal domain of a type B PutA protein contributes to aldehyde dehydrogenase activity and substrate channeling.

    Science.gov (United States)

    Luo, Min; Christgen, Shelbi; Sanyal, Nikhilesh; Arentson, Benjamin W; Becker, Donald F; Tanner, John J

    2014-09-09

    Proline utilization A (PutA) is a bifunctional enzyme that catalyzes the oxidation of proline to glutamate. Structures of type A PutAs have revealed the catalytic core consisting of proline dehydrogenase (PRODH) and Δ(1)-pyrroline-5-carboxylate dehydrogenase (P5CDH) modules connected by a substrate-channeling tunnel. Type B PutAs also have a C-terminal domain of unknown function (CTDUF) that is absent in type A PutAs. Small-angle X-ray scattering (SAXS), mutagenesis, and kinetics are used to determine the contributions of this domain to PutA structure and function. The 1127-residue Rhodobacter capsulatus PutA (RcPutA) is used as a representative CTDUF-containing type B PutA. The reaction progress curve for the coupled PRODH-P5CDH activity of RcPutA does not exhibit a time lag, implying a substrate channeling mechanism. RcPutA is monomeric in solution, which is unprecedented for PutAs. SAXS rigid body modeling with target-decoy validation is used to build a model of RcPutA. On the basis of homology to aldehyde dehydrogenases (ALDHs), the CTDUF is predicted to consist of a β-hairpin fused to a noncatalytic Rossmann fold domain. The predicted tertiary structural interactions of the CTDUF resemble the quaternary structural interactions in the type A PutA dimer interface. The model is tested by mutagenesis of the dimerization hairpin of a type A PutA and the CTDUF hairpin of RcPutA. Similar functional phenotypes are observed in the two sets of variants, supporting the hypothesis that the CTDUF mimics the type A PutA dimer interface. These results suggest annotation of the CTDUF as an ALDH superfamily domain that facilitates P5CDH activity and substrate channeling by stabilizing the aldehyde-binding site and sealing the substrate-channeling tunnel from the bulk medium.

  17. Multiple binding of thallium and rubidium to potassium-activated yeast aldehyde dehydrogenase. Influences on tertiary structure, stability and catalytic activity.

    Science.gov (United States)

    Bostian, K A; Betts, G F; Man, W K; Hughes, M N

    1982-01-01

    Univalent cation activators of aldehyde dehydrogenase have dual effects, both interpreted as cation-induced or -stabilized conformation changes. These two processes are differentiated by the time scales of their associated changes in activity. Using Tl+ as an activator, under certain conditions, the slower change in activity saturates at a Tl+ concentration which is only 0.1 Ks for the faster change. This, together with evidence for cation-induced rather than cation-stabilized conformation changes, is used to propose separate binding sites for cations responsible for the two activation processes. Equilibrium dialysis indicates 4 binding sites per active site for Rb+ or 6 sites for Tl+. At least one of the additional sites for Tl+ is an inhibitory site which has been differentiated from the activator sites on the basis of steady-state and pre-steady-state kinetic data. PMID:6758767

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

    Science.gov (United States)

    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.

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2018-04-03

    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.

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

    Science.gov (United States)

    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.

  4. Metabolism of trans, trans-muconaldehyde, a cytotoxic metabolite of benzene, in mouse liver by alcohol dehydrogenase Adh1 and aldehyde reductase AKR1A4

    International Nuclear Information System (INIS)

    Short, Duncan M.; Lyon, Robert; Watson, David G.; Barski, Oleg A.; McGarvie, Gail; Ellis, Elizabeth M.

    2006-01-01

    The reductive metabolism of trans, trans-muconaldehyde, a cytotoxic metabolite of benzene, was studied in mouse liver. Using an HPLC-based stopped assay, the primary reduced metabolite was identified as 6-hydroxy-trans, trans-2,4-hexadienal (OH/CHO) and the secondary metabolite as 1,6-dihydroxy-trans, trans-2,4-hexadiene (OH/OH). The main enzymes responsible for the highest levels of reductase activity towards trans, trans-muconaldehyde were purified from mouse liver soluble fraction first by Q-sepharose chromatography followed by either blue or red dye affinity chromatography. In mouse liver, trans, trans-muconaldehyde is predominantly reduced by an NADH-dependent enzyme, which was identified as alcohol dehydrogenase (Adh1). Kinetic constants obtained for trans, trans-muconaldehyde with the native Adh1 enzyme showed a V max of 2141 ± 500 nmol/min/mg and a K m of 11 ± 4 μM. This enzyme was inhibited by pyrazole with a K I of 3.1 ± 0.57 μM. Other fractions were found to contain muconaldehyde reductase activity independent of Adh1, and one enzyme was identified as the NADPH-dependent aldehyde reductase AKR1A4. This showed a V max of 115 nmol/min/mg and a K m of 15 ± 2 μM and was not inhibited by pyrazole

  5. A polymorphism of the aldehyde dehydrogenase 2 gene is a risk factor for multiple lacunar infarcts in Japanese men: the Takahata Study.

    Science.gov (United States)

    Nagasawa, H; Wada, M; Arawaka, S; Kawanami, T; Kurita, K; Daimon, M; Adachi, M; Hosoya, T; Emi, M; Muramatsu, M; Kato, T

    2007-04-01

    The objective of the present study was to examine the association between a polymorphism of the aldehyde dehydrogenase 2 (ALDH2) gene and lacunar infarcts of the brain. We conducted a population-based, cross-sectional study on residents from two age groups (61- and 72-year olds). A total of 376 subjects participated in the study, which included brain magnetic resonance image and genetic analysis of the ALDH2 gene. Of the 61- and 72-year-old subjects, 46.4% and 64.3%, respectively, had one or more lacunar infarcts. The average number of infarcts also increased from 2.0 to 2.8 in men and from 2.3 to 3.5 in women. No significant association between the ALDH2 genotype and the presence of lacunar infarction (> or =1) was found. However, in subjects with lacunar infarction, the genotype of ALDH2 *1/*1 was associated with a larger number of the lesion ['single' versus 'multiple' odds ratio (OR) 3.73, 95%CI: 1.43-9.74] in men. The OR was comparable even after adjusting for alcohol consumption, tobacco habits, age, hypertension, hypercholesterolemia, and diabetes mellitus (DM) (OR 3.88; 95% CI: 1.10-13.66). In women, there was no significant association between the ALDH2 genotypes and lacunar infarcts. The present study revealed that the ALDH2 *1/*1 genotype was significantly associated with the prevalence of multiple lacunar infarcts in Japanese men.

  6. 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.

    Science.gov (United States)

    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

  7. Association of an aldehyde dehydrogenase 2 (ALDH2) gene polymorphism with hyper-low-density lipoprotein cholesterolemia in a Japanese population.

    Science.gov (United States)

    Kotani, Kazuhiko; Sakane, Naoki; Yamada, Toshiyuki

    2012-01-01

    The relationship among alcohol metabolism, lipid profile and cardiovascular disease has been a matter of concern, and aldehyde dehydrogenase-2 (ALDH2) is one of the key enzymes involved in alcohol metabolism. The frequency of ALDH2 gene G/A polymorphism (with the substitution of glutamic acid to lysine) varies widely among ethnic groups; the polymorphism is prevalent among Asian people but rare in other ethnic groups. The objective of our study was to investigate the association between the ALDH2 gene G/A polymorphism and lipid profile, including the low-density lipoprotein cholesterol (LDL-C) status, in a general Japanese population with no or light-to-moderate alcohol drinking habits. Anthropometric and biochemical variables including lipid- and glucose-related factors were measured in a total of 383 Japanese participants (170 males and 213 females; mean age, 45 +/- 8.6 years), free of cardiovascular disease. All participants were genotyped by an allele-specific DNA assay. The numbers of participants with the G/ G, G/A and A/A genotypes were 213, 139 and 31, respectively. The percentages of hyper-LDL-cholesterolemia (identified by LDL-C > or = 3.63 mmol/L) were 31.9%, 45.3% and 29.0% in participants with the G/G, G/A and A/A genotypes, respectively. Carrying the G/A + AA genotype was a significant and positive factor related to hyper-LDL-cholesterolemia with an odds ratio of 1.62 (95% CI: 1.04-2.52) after adjusting for the other variables including drinking status. Our findings suggest that the ALDH2 gene G/A polymorphism can affect the lipid profile such as LDL-C status in this population. The association between the polymorphism and LDL-C status warrants further investigation.

  8. Aldehyde dehydrogenase 1 is a marker for normal and malignant human colonic stem cells (SC) and tracks SC overpopulation during colon tumorigenesis.

    Science.gov (United States)

    Huang, Emina H; Hynes, Mark J; Zhang, Tao; Ginestier, Christophe; Dontu, Gabriela; Appelman, Henry; Fields, Jeremy Z; Wicha, Max S; Boman, Bruce M

    2009-04-15

    Although the concept that cancers originate from stem cells (SC) is becoming scientifically accepted, mechanisms by which SC contribute to tumor initiation and progression are largely unknown. For colorectal cancer (CRC), investigation of this problem has been hindered by a paucity of specific markers for identification and isolation of SC from normal and malignant colon. Accordingly, aldehyde dehydrogenase 1 (ALDH1) was investigated as a possible marker for identifying colonic SC and for tracking them during cancer progression. Immunostaining showed that ALDH1(+) cells are sparse and limited to the normal crypt bottom, where SCs reside. During progression from normal epithelium to mutant (APC) epithelium to adenoma, ALDH1(+) cells increased in number and became distributed farther up the crypt. CD133(+) and CD44(+) cells, which are more numerous and broadly distributed in normal crypts, showed similar changes during tumorigenesis. Flow cytometric isolation of cancer cells based on enzymatic activity of ALDH (Aldefluor assay) and implantation of these cells in nonobese diabetic-severe combined immunodeficient mice (a) generated xenograft tumors (Aldefluor(-) cells did not), (b) generated them after implanting as few as 25 cells, and (c) generated them dose dependently. Further isolation of cancer cells using a second marker (CD44(+) or CD133(+) serially) only modestly increased enrichment based on tumor-initiating ability. Thus, ALDH1 seems to be a specific marker for identifying, isolating, and tracking human colonic SC during CRC development. These findings also support our original hypothesis, derived previously from mathematical modeling of crypt dynamics, that progressive colonic SC overpopulation occurs during colon tumorigenesis and drives CRC development.

  9. Effects of Betaine Aldehyde Dehydrogenase-Transgenic Soybean on Phosphatase Activities and Rhizospheric Bacterial Community of the Saline-Alkali Soil

    Directory of Open Access Journals (Sweden)

    Ying Nie

    2016-01-01

    Full Text Available The development of transgenic soybean has produced numerous economic benefits; however the potential impact of root exudates upon soil ecological systems and rhizospheric soil microbial diversity has also received intensive attention. In the present study, the influence of saline-alkali tolerant transgenic soybean of betaine aldehyde dehydrogenase on bacterial community structure and soil phosphatase during growth stages was investigated. The results showed that, compared with nontransgenic soybean as a control, the rhizospheric soil pH of transgenic soybean significantly decreased at the seedling stage. Compared to HN35, organic P content was 13.5% and 25.4% greater at the pod-filling stage and maturity, respectively. The acid phosphatase activity of SRTS was significantly better than HN35 by 12.74% at seedling, 14.03% at flowering, and 59.29% at podding, while alkaline phosphatase achieved maximum activity in the flowering stage and was markedly lower than HN35 by 13.25% at pod-filling. The 454 pyrosequencing technique was employed to investigate bacterial diversity, with a total of 25,499 operational taxonomic units (OTUs obtained from the 10 samples. Notably, the effect of SRTS on microbial richness and diversity of rhizospheric soil was marked at the stage of podding and pod-filling. Proteobacteria, Acidobacteria, and Actinobacteria were the dominant phyla among all samples. Compared with HN35, the relative abundance of Proteobacteria was lower by 2.01%, 2.06%, and 5.28% at the stage of seedling, at pod-bearing, and at maturity. In genus level, the relative abundance of Gp6, Sphingomonas sp., and GP4 was significantly inhibited by SRTS at the stage of pod-bearing and pod-filling.

  10. Preferential antitumor effect of the Src inhibitor dasatinib associated with a decreased proportion of aldehyde dehydrogenase 1-positive cells in breast cancer cells of the basal B subtype

    Directory of Open Access Journals (Sweden)

    Watanabe Mika

    2010-10-01

    Full Text Available Abstract Background Recent studies have suggested that the Src inhibitor dasatinib preferentially inhibits the growth of breast cancer cells of the basal-like subtype. To clarify this finding and further investigate combined antitumor effects of dasatinib with cytotoxic agents, a panel of breast cancer cell lines of various subtypes was treated with dasatinib and/or chemotherapeutic agents. Methods Seven human breast cancer cell lines were treated with dasatinib and/or seven chemotherapeutic agents. Effects of the treatments on c-Src activation, cell growth, cell cycle, apoptosis and the proportion of aldehyde dehydrogenase (ALDH 1-positive cells were examined. Results The 50%-growth inhibitory concentrations (IC50s of dasatinib were much lower in two basal B cell lines than those in the other cell lines. The IC50s of chemotherapeutic agents were not substantially different among the cell lines. Dasatinib enhanced antitumor activity of etoposide in the basal B cell lines. Dasatinib induced a G1-S blockade with a slight apoptosis, and a combined treatment of dasatinib with etoposide also induced a G1-S blockade in the basal B cell lines. Dasatinib decreased the expression levels of phosphorylated Src in all cell lines. Interestingly, dasatinib significantly decreased the proportion of ALDH1-positive cells in the basal B cell lines but not in the other cell lines. Conclusions The present study indicates that dasatinib preferentially inhibits the growth of breast cancer cells of the basal B subtype associated with a significant loss of putative cancer stem cell population. A combined use of dasatinib with etoposide additively inhibits their growth. Further studies targeting breast cancers of the basal B subtype using dasatinib with cytotoxic agents are warranted.

  11. In vitro oxidative metabolism of 6-mercaptopurine in human liver: insights into the role of the molybdoflavoenzymes aldehyde oxidase, xanthine oxidase, and xanthine dehydrogenase.

    Science.gov (United States)

    Choughule, Kanika V; Barnaba, Carlo; Joswig-Jones, Carolyn A; Jones, Jeffrey P

    2014-08-01

    Anticancer agent 6-mercaptopurine (6MP) has been in use since 1953 for the treatment of childhood acute lymphoblastic leukemia (ALL) and inflammatory bowel disease. Despite being available for 60 years, several aspects of 6MP drug metabolism and pharmacokinetics in humans are unknown. Molybdoflavoenzymes such as aldehyde oxidase (AO) and xanthine oxidase (XO) have previously been implicated in the metabolism of this drug. In this study, we investigated the in vitro metabolism of 6MP to 6-thiouric acid (6TUA) in pooled human liver cytosol. We discovered that 6MP is metabolized to 6TUA through sequential metabolism via the 6-thioxanthine (6TX) intermediate. The role of human AO and XO in the metabolism of 6MP was established using the specific inhibitors raloxifene and febuxostat. Both AO and XO were involved in the metabolism of the 6TX intermediate, whereas only XO was responsible for the conversion of 6TX to 6TUA. These findings were further confirmed using purified human AO and Escherichia coli lysate containing expressed recombinant human XO. Xanthine dehydrogenase (XDH), which belongs to the family of xanthine oxidoreductases and preferentially reduces nicotinamide adenine dinucleotide (NAD(+)), was shown to contribute to the overall production of the 6TX intermediate as well as the final product 6TUA in the presence of NAD(+) in human liver cytosol. In conclusion, we present evidence that three enzymes, AO, XO, and XDH, contribute to the production of 6TX intermediate, whereas only XO and XDH are involved in the conversion of 6TX to 6TUA in pooled HLC. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  12. Nitrite reductase activity of rat and human xanthine oxidase, xanthine dehydrogenase, and aldehyde oxidase: evaluation of their contribution to NO formation in vivo.

    Science.gov (United States)

    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.

  13. Aldehyde Dehydrogenase 1 Is a Marker for Normal and Malignant Human Colonic Stem Cells (SC) and Tracks SC Overpopulation during Colon Tumorigenesis

    Science.gov (United States)

    Huang, Emina H.; Hynes, Mark J.; Zhang, Tao; Ginestier, Christophe; Dontu, Gabriela; Appelman, Henry; Fields, Jeremy Z.; Wicha, Max S.; Boman, Bruce M.

    2009-01-01

    Although the concept that cancers originate from stem cells (SC) is becoming scientifically accepted, mechanisms by which SC contribute to tumor initiation and progression are largely unknown. For colorectal cancer (CRC), investigation of this problem has been hindered by a paucity of specific markers for identification and isolation of SC from normal and malignant colon. Accordingly, aldehyde dehydrogenase 1 (ALDH1) was investigated as a possible marker for identifying colonic SC and for tracking them during cancer progression. Immunostaining showed that ALDH1+ cells are sparse and limited to the normal crypt bottom, where SCs reside. During progression from normal epithelium to mutant (APC) epithelium to adenoma, ALDH1+ cells increased in number and became distributed farther up the crypt. CD133+ and CD44+ cells, which are more numerous and broadly distributed in normal crypts, showed similar changes during tumorigenesis. Flow cytometric isolation of cancer cells based on enzymatic activity of ALDH (Aldefluor assay) and implantation of these cells in nonobese diabetic–severe combined immunodeficient mice (a) generated xenograft tumors (Aldefluor− cells did not), (b) generated them after implanting as few as 25 cells, and (c) generated them dose dependently. Further isolation of cancer cells using a second marker (CD44+ or CD133+ serially) only modestly increased enrichment based on tumor-initiating ability. Thus, ALDH1 seems to be a specific marker for identifying, isolating, and tracking human colonic SC during CRC development. These findings also support our original hypothesis, derived previously from mathematical modeling of crypt dynamics, that progressive colonic SC overpopulation occurs during colon tumorigenesis and drives CRC development. PMID:19336570

  14. [Activity of the octanol dehydrogenase, of the alcool dehydrogenase and aldehyde dehydrogenase on the farnesol metabolism. Photoperiodic and neurhormonale regulation, controlling the metabolism of the juvenile hormone, in Pieris brassicae (author's transl)].

    Science.gov (United States)

    L'Hélias, C

    1979-01-01

    The antagonistic photoperiodic behaviour of the farnesol dehydrogenases indicates that the photonic control mechanism of the brain acts on the farnesol derivates. This cerebral control is double. The first system, linked at the allatotrope function is proportionnal at the photoperiod and acts on the octanol dehydrogenase 0,32. The second system controle the deshydrogenases ADH bands 0,50--0,58, is linked at the darkness. It is linked also at the neurocerebral activity then it stops its activity at the 4th day of the 5th stage. This last seems to be the determinating control for the establishment of the diapause since in short photoperiod, when the inhibition by this system ends, the alcool dehydrogenases 0,50-0,58 series is suractivated in rate with the lasting of the scotophase. In darkness, the 1st system functionnes cyclically and has a maximum synchron with the single maximum of the 2nd system. Inversally, in continuous light, the 2nd system is synchronisated with the 1st which has a prolongated action, maybe linked with a prolongated activity of the neurosecretory cells of the pars intercerebralis and corpora allata.

  15. High ethanol and acetaldehyde impair spatial memory in mouse models: opposite effects of aldehyde dehydrogenase 2 and apolipoprotein E on memory.

    Science.gov (United States)

    Jamal, Mostofa; Ameno, Kiyoshi; Miki, Takanori; Tanaka, Naoko; Ono, Junichiro; Shirakami, Gotaro; Sultana, Ruby; Yu, Nakamura; Kinoshita, Hiroshi

    2012-05-01

    Aldehyde dehydrogenase 2 deficiency may directly contribute to excess acetaldehyde (AcH) accumulation after ethanol (EtOH) drinking and AcH mediates some of the behavioral effects of EtOH. Apolipoprotein E has been suggested to be involved in the alteration of attention and memory. We have chosen Aldh2-knockout (Aldh2-KO), ApoE-KO, and their wild-type (WT) control mice to examine the effects of EtOH and AcH on spatial memory and to compare the possible relationship between genetic deficiency and memory using two behavioral assessments. Mice were trained for 4 days, with EtOH (0.5, 1.0, 2.0 g/kg) being given intraperitoneally on day 4. A probe trial was given on day 5 in the non-EtOH state in the Morris water maze (MWM). The results showed that 2.0 g/kg EtOH increased errors, indicating memory impairment on the eight-arm radial maze (RAM) for all the mice studied. One gram per kilogram EtOH impaired the performance of Aldh2-KO and ApoE-KO mice, but not WT mice. We found similar effects of EtOH on the MWM performance, with 2.0 g/kg EtOH increasing the latencies. One gram per kilogram EtOH increased the latencies of Aldh2-KO and WT mice, but not ApoE-KO mice. The 2.0 g/kg EtOH-induced memory impairment in Aldh2-KO mice was greater, suggesting an AcH effect. Furthermore, time spent on the probe trial was shorter in mice that had previously received 2.0 g/kg EtOH. ApoE-KO mice learned more slowly, while Aldh2-KO mice learned more quickly. Both the RAM and MWM results suggest that high EtOH and AcH impair spatial memory in mice, while lower doses do not have consistent memory effects. In addition, we conclude that genetic differences might underlie some of EtOH's effects on memory. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Purification, crystallization and preliminary X-ray analysis of recombinant betaine aldehyde dehydrogenase 2 (OsBADH2), a protein involved in jasmine aroma, from Thai fragrant rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Kuaprasert, Buabarn; Silprasit, Kun; Horata, Natharinee; Khunrae, Pongsak; Wongpanya, Ratree; Boonyalai, Nonlawat; Vanavichit, Apichart; Choowongkomon, Kiattawee

    2011-01-01

    Crystals of betaine aldehyde dehydrogenase 2 from rice (O. sativa L.) belonged to a C-centred orthorhombic space group and diffraceted X-rays to 2.6 Å resolution. Fragrant rice (Oryza sativa L.) betaine aldehyde dehydrogenase 2 (OsBADH2) is a key enzyme in the synthesis of fragrance aroma compounds. The extremely low activity of OsBADH2 in catalyzing the oxidation of acetaldehyde is believed to be crucial for the accumulation of the volatile compound 2-acetyl-1-pyrroline (2AP) in many scented plants, including fragrant rice. Recombinant fragrant rice OsBADH2 was expressed in Escherichia coli as an N-terminal hexahistidine fusion protein, purified using Ni Sepharose affinity chromatography and crystallized using the microbatch method. Initial crystals were obtained within 24 h using 0.1 M Tris pH 8.5 with 30%(w/v) PEG 4000 and 0.2 M magnesium chloride as the precipitating agent at 291 K. Crystal quality was improved when the enzyme was cocrystallized with NAD + . Improved crystals were grown in 0.1 M HEPES pH 7.4, 24%(w/v) PEG 4000 and 0.2 M ammonium chloride and diffracted to beyond 2.95 Å resolution after being cooled in a stream of N 2 immediately prior to X-ray diffraction experiments. The crystals belonged to space group C222 1 , with unit-cell parameters a = 66.03, b = 183.94, c = 172.28 Å. An initial molecular-replacement solution has been obtained and refinement is in progress

  17. 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

    Directory of Open Access Journals (Sweden)

    Liuyi Hao

    2018-04-01

    Full Text Available 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/6 J mice were exposed to alcohol for 8 weeks with MitoQ supplementation (5 mg/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. Keywords: Aldehyde dehydrogenase 2

  18. A Novel Approach for Overcoming Drug Resistance in Breast Cancer Chemotherapy by Targeting new Synthetic Curcumin Analogues Against Aldehyde Dehydrogenase 1 (ALDH1A1) and Glycogen Synthase Kinase-3 β (GSK-3β).

    Science.gov (United States)

    Kesharwani, Rajesh Kumar; Srivastava, Vandana; Singh, Prabhakar; Rizvi, Syed Ibrahim; Adeppa, Kuruba; Misra, Krishna

    2015-08-01

    Breast cancer stem cells are well known to resist the traditional methods like chemo and radio therapy. Aldehyde dehydrogenase 1 (ALDHIA1) and glycogen synthase kinase-3 β (GSK-3β) are the two selected proteins for study, due to their overexpression and upregulation in breast cancer cells. Curcumin, the yellow pigment of the spice turmeric, is widely reported as an antioxidant and acts as a synergist along with traditional drugs. Under hypoxic conditions, it gets converted to free radical which causes apoptosis. Three naturally occurring curcuminoids, i.e. curcumin, demethoxycurcumin, and bisdemethoxycurcumin along with five derivatives/analogues of curcumin, viz. 4,4'-di-O-(carboxy-methyl)-curcumin, 4-O-(2-hydroxyethyl)curcumin, 4,4'-di-O-allyl-curcumin, 4,4'-di-O-(acetyl)-curcumin, and 3,3'-bisdemethylcurcumin were synthesized and evaluated for their anti-breast cancer potential by docking simulation and assessment of their antioxidant character, studied via 2, 2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(·+)) radical cation scavenging assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH·) radical, and ferric reducing ability potential (FRAP) assay. A co-relation between structure and activity of curcuminoids/its analogues and derivatives has been worked out.

  19. [Effects of panthenol and carnitine on aldehyde metabolic enzymes in rats with tetrachloromethane-induced liver injury].

    Science.gov (United States)

    Satanovskaia, V I; Pron'ko, P S; Gaĭshmanova, A V; Miskevich, D A

    2009-01-01

    Tetrachloromethane (2 g/kg, intragastric) produced a decrease in the activity of NAD- and NADH- dependent aldehyde dehydrogenases with high Km for aldehydes in rat liver. Panthenol and L-carnitine administered separately normalized the activity of aldehyde dehydrogenases, while a combination of the drugs did not produce any significant effect.

  20. Deficiency in the amino aldehyde dehydrogenase encoded by GmAMADH2, the homologue of rice Os2AP, enhances 2-acetyl-1-pyrroline biosynthesis in soybeans (Glycine max L.).

    Science.gov (United States)

    Arikit, Siwaret; Yoshihashi, Tadashi; Wanchana, Samart; Uyen, Tran T; Huong, Nguyen T T; Wongpornchai, Sugunya; Vanavichit, Apichart

    2011-01-01

    2-Acetyl-1-pyrroline (2AP), the volatile compound that provides the 'popcorn-like' aroma in a large variety of cereal and food products, is widely found in nature. Deficiency in amino aldehyde dehydrogenase (AMADH) was previously shown to be the likely cause of 2AP biosynthesis in rice (Oryza sativa L.). In this study, the validity of this mechanism was investigated in soybeans (Glycine max L.). An assay of AMADH activity in soybeans revealed that the aromatic soybean, which contains 2AP, also lacked AMADH enzyme activity. Two genes, GmAMADH1 and GmAMADH2, which are homologous to the rice Os2AP gene that encodes AMADH, were characterized. The transcription level of GmAMADH2 was lower in aromatic varieties than in nonaromatic varieties, whereas the expression of GmAMADH1 did not differ. A double nucleotide (TT) deletion was found in exon 10 of GmAMADH2 in all aromatic varieties. This variation caused a frame-shift mutation and a premature stop codon. Suppression of GmAMADH2 by introduction of a GmAMADH2-RNAi construct into the calli of the two nonaromatic wild-type varieties inhibited the synthesis of AMADH and induced the biosynthesis of 2AP. These results suggest that deficiency in the GmAMADH2 product, AMADH, plays a similar role in soybean as in rice, which is to promote 2AP biosynthesis. This phenomenon might be a conserved mechanism among plant species. © 2010 The Authors. Plant Biotechnology Journal © 2010 Society for Experimental Biology and Blackwell Publishing Ltd.

  1. Aldehyde dehydrogenase 2 deficiency increases resting-state glutamate and expression of the GluN1 subunit of N-methyl-D-aspartate receptor in the frontal cortex of mice.

    Science.gov (United States)

    Jamal, Mostofa; Ono, Junichiro; Ameno, Kiyoshi; Shirakami, Gotaro; Tanaka, Naoko; Takakura, Ayaka; Kinoshita, Hiroshi

    2015-01-15

    Our previous study showed that Aldh2-knockout (Aldh2-KO) mice, an animal model of inactive aldehyde dehydrogenase 2 (ALDH2), have better spatial memory when compared with wild-type (WT) mice. Given that the neurotransmitter glutamate has been associated with learning and memory, the goal of the present study was to investigate whether the strain-dependent difference in spatial memory was associated with changes in glutamate transmitter levels or receptor function in the frontal cortex of Aldh2-KO and WT mice. Thus, we first measured extracellular glutamate levels in free-moving mice using microdialysis. Second, we studied protein expression of the N-methyl-D-aspartate (NMDA) receptor (GluN1) subunit and the α-amino-3-hydroxy-5 methylisoxazole-4-propionic acid (AMPA) receptor (GluA1) subunit in lipid raft fractions using Western blot (WB). The samples were collected for WB, and lipid rafts were prepared from the insoluble fraction of homogenate tissue. Protein concentration was measured in the whole cell lysate (WCL) and in five separate lipid raft fractions. Cholesterol was also measured in all fractions 1-5. The microdialysis study revealed that basal glutamate concentration in the dialysates was approximately three-fold (0.27 ± 0.12 μM) higher in Aldh2-KO mice than in WT (0.10 ± 0.03 μM) mice. We also found an increase in the expression of GluN1 in Aldh2-KO mice compared with WT mice, both in the WCL and fraction 5, but GluA1 levels were unchanged as measured by WB. Our novel findings provide the first evidence for the role of ALDH2 in glutamate release and GluN1 protein expression in the frontal cortex. The observed strain differences in glutamate levels and GluN1 expression may suggest that enhanced glutamatergic function facilitates improved spatial memory in Aldh2-KO mice and such observation deserves further investigation. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. A deletion of the gene encoding amino aldehyde dehydrogenase enhances the "pandan-like" aroma of winter melon (Benincasa hispida) and is a functional marker for the development of the aroma.

    Science.gov (United States)

    Ruangnam, Saowalak; Wanchana, Samart; Phoka, Nongnat; Saeansuk, Chatree; Mahatheeranont, Sugunya; de Hoop, Simon Jan; Toojinda, Theerayut; Vanavichit, Apichart; Arikit, Siwaret

    2017-12-01

    The gene conferring a "pandan-like" aroma of winter melon was identified. The sequence variation (804-bp deletion) found in the gene was used as the target for functional marker development. Winter melon (Benincasa hispida), a member of the Cucurbitaceae family, is a commonly consumed vegetable in Asian countries that is popular for its nutritional and medicinal value. A "pandan-like" aroma, which is economically important in crops including rice and soybean, is rarely found in most commercial varieties of winter melon, but is present in some landraces. This aroma is a value-added potential trait in breeding winter melon with a higher economic value. In this study, we confirmed that the aroma of winter melon is due to the potent volatile compound 2-acetyl-1-pyrroline (2AP) as previously identified in other plants. Based on an analysis of public transcriptome data, BhAMADH encoding an aminoaldehyde dehydrogenase (AMADH) was identified as a candidate gene conferring aroma of winter melon. A sequence comparison of BhAMADH between the aromatic and non-aromatic accessions revealed an 804-bp deletion encompassing exons 11-13 in the aromatic accession. The deletion caused several premature stop codons and could result in a truncated protein with a length of only 208 amino acids compared with 503 amino acids in the normal protein. A functional marker was successfully developed based on the 804-bp deletion and validated in 237 F 2 progenies. A perfect association of the marker genotypes and aroma phenotypes indicates that BhAMADH is the major gene conferring the aroma. The recently developed functional marker could be efficiently used in breeding programs for the aroma trait in winter melon.

  3. 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.

    Science.gov (United States)

    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 cancer cells, providing also a first evidence that there is no correlation between CSCs and BRCA status. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Characterization of retinaldehyde dehydrogenase 3

    OpenAIRE

    Graham, Caroline E.; Brocklehurst, Keith; Pickersgill, Richard W.; Warren, Martin J.

    2006-01-01

    RALDH3 (retinal dehydrogenase 3) was characterized by kinetic and binding studies, protein engineering, homology modelling, ligand docking and electrostatic-potential calculations. The major recognition determinant of an RALDH3 substrate was shown to be an eight-carbon chain bonded to the aldehyde group whose kinetic influence (kcat/Km at pH 8.5) decreases when shortened or lengthened. Surprisingly, the β-ionone ring of all-trans-retinal is not a major recognition site. The dissociation const...

  5. Aldehyde Dehydrogenase 1 and Raf Kinase Inhibitor Protein ...

    African Journals Online (AJOL)

    interestingly defines the higher expression in low grade cervical cancer to regulate the tumour, but shows little or no very mild ... Conclusion: ALDH1 and RKIP marker in association correlation with Sox2 aids in defining the proliferative ability of .... endogenous peroxidase activity was blocked by immersing the sections in ...

  6. Aldehyde Dehydrogenase 1 and Raf Kinase Inhibitor Protein ...

    African Journals Online (AJOL)

    Immunohistochemical and Western blotting techniques were employed to study the expression profiles of ALDH1 and RKIP. The specificity of Sox2 that determines cancer stem cells served as control to validate ALDH1 and RKIP expressions. Results: Histological data helped to differentiate low from high grade cervical ...

  7. Identification of lactaldehyde dehydrogenase and glycolaldehyde dehydrogenase as functions of the same protein in Escherichia coli.

    Science.gov (United States)

    Caballero, E; Baldomá, L; Ros, J; Boronat, A; Aguilar, J

    1983-06-25

    Lactaldehyde dehydrogenase is an enzyme involved in the aerobic metabolism of fucose in wild type Escherichia coli, and glycolaldehyde dehydrogenase is an enzyme involved in the metabolism of ethylene glycol in mutant cells able to utilize this glycol. Both enzyme sources display oxidative activity on either substrate with a constant ratio between these activities. We have found that both enzymatic activities present the same electrophoretic mobility when crude extracts were electrophoresed in polyacrylamide gels and the gels stained for enzyme activities. Furthermore, both enzymatic activities co-chromatograph in a DEAE-Sephadex column. If lactaldehyde dehydrogenase of wild type cells is purified near homogeneity and the purification procedure is screened for both aldehydes as substrates, only one enzyme is apparent, giving again a constant ratio between lactaldehyde and glycolaldehyde dehydrogenase activities. Genetic evidence of the fact that both activities are functions of the same protein is provided by the observation that mutation to thermosensitivity for the production of lactaldehyde dehydrogenase affected in the same way the production of glycolaldehyde dehydrogenase. Glycolaldehyde dehydrogenase from mutant cells is purified in a procedure coincident with the lactaldehyde dehydrogenase purification, yielding a single enzyme electrophoretically indistinguishable from the purified lactaldehyde dehydrogenase. Peptide mapping of the purified preparation after digestion with chymotrypsin or Staphylococcus aureus protease V8 gives an indistinguishable band pattern between both enzymes.

  8. Formyl-d aromatic aldehydes

    International Nuclear Information System (INIS)

    Chancellor, T.; Quill, M.; Bergbreiter, D.E.; Newcomb, M.

    1978-01-01

    A simple exchange reaction for preparation of aldehydes labeled with deuterium at the formyl carbon is described. It can be successfully accomplished with several aromatic aldehydes, a catalytic or stoichiometric amount of either potassium cyanide or a thiazolium salt, a weak Lewis base, and deuterium oxide as the deuterium source

  9. First general methods toward aldehyde enolphosphates.

    Science.gov (United States)

    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.

  10. Alcohol, Aldehydes, Adducts and Airways

    Directory of Open Access Journals (Sweden)

    Muna Sapkota

    2015-11-01

    Full Text Available 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.

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

    Science.gov (United States)

    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 ...

  12. Glucose-6-phosphate dehydrogenase

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003671.htm Glucose-6-phosphate dehydrogenase test To use the sharing features on this page, please enable JavaScript. Glucose-6-phosphate dehydrogenase (G6PD) is a protein that ...

  13. Structural and mechanistic aspects of alcohol dehydrogenase function

    OpenAIRE

    Svensson, Stefan

    1999-01-01

    Vertebrates possess a complex alcohol dehydrogenase (ADH) system composed of multiple molecular forms, which are currently classified into seven classes according to their structural properties. ADHs are dimeric zinc metalloenzymes that catalyze the reversible oxidation of alcohols to aldehydes/ketones using NAD+/NADH as electron acceptor and donor, respectively. The classes have broad but only partially overlapping substrate repertoires. This thesis mainly deals with mechan...

  14. Chromate reduction by rabbit liver aldehyde oxidase

    Energy Technology Data Exchange (ETDEWEB)

    Banks, R.B.; Cooke, R.T. Jr.

    1986-05-29

    Chromate was reduced during the oxidation of 1-methylnicotinamide chlorine by partially purified rabbit liver aldehyde oxidase. In addition to l-methylnicotinamide, several other electron donor substrates for aldehyde oxidase were able to support the enzymatic chromate reduction. The reduction required the presence of both enzyme and the electron donor substrate. The rate of the chromate reduction was retarded by inhibitors or aldehyde oxidase but was not affected by substrates or inhibitors of xanthine oxidase. These results are consistent with the involvement of aldehyde oxidase in the reduction of chromate by rabbit liver cytosolic enzyme preparations.

  15. Diabetes Impairs the Aldehyde Detoxifying Capacity of the Retina.

    Science.gov (United States)

    McDowell, Rosemary E; McGahon, Mary K; Augustine, Josy; Chen, Mei; McGeown, J Graham; Curtis, Tim M

    2016-09-01

    We studied whether the accumulation of advanced lipoxidation end-products (ALEs) in the diabetic retina is linked to the impairment of lipid aldehyde detoxification mechanisms. Retinas were collected from nondiabetic and diabetic rats and processed for conventional and quantitative RT-PCR (qRT-PCR), Western blotting, immunohistochemistry, and aldehyde dehydrogenase (ALDH) activity assays. The effect of the ALDH1a1 inhibitor, NCT-501, on ALE accumulation and cell viability in cultured Müller glia also was investigated. The rat retina expressed a range of lipid aldehyde detoxifying ALDH and aldo-keto reductase (AKR) genes. In diabetes, mRNA levels were reduced for 5 of 9 transcripts tested. These findings contrasted with those in the lens and cornea where many of these enzymes were upregulated. We have reported previously accumulation of the acrolein (ACR)-derived ALE, FDP-lysine, in retinal Müller glia during diabetes. In the present study, we show that the main ACR-detoxifying ALDH and AKR genes expressed in the retina, namely, ALDH1a1, ALDH2, and AKR1b1, are principally localized to Müller glia. Diabetes-induced FDP-lysine accumulation in Müller glia was associated with a reduction in ALDH1a1 mRNA and protein expression in whole retina and a decrease in ALDH1a1-immunoreactivity specifically within these cells. No such changes were detected for ALDH2 or AKR1b1. Activity of ALDH was suppressed in the diabetic retina and blockade of ALDH1a1 in cultured Müller glia triggered FDP-lysine accumulation and reduced cell viability. These findings suggest that downregulation of ALDH and AKR enzymes, particularly ALDH1a1, may contribute ALE accumulation in the diabetic retina.

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

    Science.gov (United States)

    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.

  17. Kinetic and chemical analyses of the cytokinin dehydrogenase-catalysed reaction : correlations with the crystal structure

    NARCIS (Netherlands)

    Popelková, Hana; Fraaije, Marco W.; Novák, Ondřej; Frébortová, Jitka; Bilyeu, Kristin D.; Frébort, Ivo

    2006-01-01

    CKX (cytokinin dehydrogenase) is a flavoprotein that cleaves cytokinins to adenine and the corresponding side-chain aldehyde using a quinone-type electron acceptor. In the present study, reactions of maize (Zea mays) CKX with five different substrates (N6-isopentenyladenine, trans-zeatin, kinetin,

  18. Emissions of odorous aldehydes from alkyd paint

    Science.gov (United States)

    Chang, John C. S.; Guo, Zhishi

    Aldehyde emissions are widely held responsible for the acrid after-odor of drying alkyd-based paint films. The aldehyde emissions from three different alkyd paints were measured in small environ-mental chambers. It was found that, for each gram of alkyd paint applied, more than 2 mg of aldehydes (mainly hexanal) were emitted during the curing (drying) period. Since no measurable hexanal was found in the original paint, it is suspected that the aldehydes emitted were produced by autoxidation of the unsaturated fatty acid esters in the alkyd resins. The hexanal emission rate was simulated by a model assuming that the autoxidation process was controlled by a consecutive first-order reaction mechanism. Using the emission rate model, indoor air quality simulation indicated that the hexanal emissions can result in prolonged (several days) exposure risk to occupants. The occupant exposure to aldehydes emitted from alkyd paint also could cause sensory irritation and other health concerns.

  19. S-Nitrosomycothiol Reductase and Mycothiol Are Required for Survival Under Aldehyde Stress and Biofilm Formation in Mycobacterium smegmatis

    Science.gov (United States)

    Vargas, Derek; Hageman, Samantha; Gulati, Megha; Nobile, Clarissa J.; Rawat, Mamta

    2017-01-01

    We show that Mycobacterium smegmatis mutants disrupted in mscR, coding for a dual function S-nitrosomycothiol reductase and formaldehyde dehydrogenase, and mshC, coding for a mycothiol ligase and lacking mycothiol (MSH), are more susceptible to S-nitrosoglutathione (GSNO) and aldehydes than wild type. MSH is a cofactor for MscR, and both mshC and mscR are induced by GSNO and aldehydes. We also show that a mutant disrupted in egtA, coding for a γ-glutamyl cysteine synthetase and lacking in ergothioneine, is sensitive to nitrosative stress but not to aldehydes. In addition, we find that MSH and S-nitrosomycothiol reductase are required for normal biofilm formation in M. smegmatis, suggesting potential new therapeutic pathways to target to inhibit or disrupt biofilm formation. PMID:27321674

  20. Myoglobin-Catalyzed Olefination of Aldehydes.

    Science.gov (United States)

    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.

  1. Chapter 18 (Part 2): Aldehydes & Ketones

    OpenAIRE

    Christiansen, Mike A

    2012-01-01

    In this video I'll teach you about what happens when we add acetylide, cyanide, and Grignard reagents to aldehydes and ketones. I also provide in-depth coverage on the reaction of aldehydes, ketones, carboxylic acids, esters, amides, and acyl (acid) chlorides with sodium borohydride (NaBH4), lithium aluminum hydride (LiAlH4), and DIBAL-H (or "diisobutyl aluminum hydride). --Dr. Mike Christiansen from Utah State University

  2. Efficient and Highly Aldehyde Selective Wacker Oxidation

    KAUST Repository

    Teo, Peili

    2012-07-06

    A method for efficient and aldehyde-selective Wacker oxidation of aryl-substituted olefins using PdCl 2(MeCN) 2, 1,4-benzoquinone, and t-BuOH in air is described. Up to a 96% yield of aldehyde can be obtained, and up to 99% selectivity can be achieved with styrene-related substrates. © 2012 American Chemical Society.

  3. Simultaneous immobilization of dehydrogenases on polyvinylidene difluoride resin after separation by non-denaturing two-dimensional electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Shimazaki, Youji [Graduate School of Science and Engineering (Science Section) and Venture Business Laboratory, Ehime University, Bunkyo-cho 2-5, Matsuyama City 790-8577 (Japan)], E-mail: yoji@dpc.ehime-u.ac.jp; Kadota, Mariko [Faculty of Science, Ehime University, Matsuyama (Japan)

    2008-06-16

    We detected mouse liver malate, sorbitol and aldehyde dehydrogenases by negative staining, analysis of malate and sorbitol dehydrogenase activities using each substrate, and electron transfers including nicotinamide adenine dinucleotide (NAD) and nitroblue tetrazolium in non-denaturing two-dimensional electrophoresis (2-DE) gel. Dehydrogenases were also identified by electrospray ionization tandem mass spectrometry (ESI-MS/MS) after 2-DE separation and protein detection by negative staining. Spots of dehydrogenases separated by 2-DE were excised, and simultaneously transferred and immobilized on polyvinylidene difuoride (PVDF) resin by electrophoresis. The dehydrogenase activities remained intact after immobilization. In conclusion, resin-immobilized dehydrogenases can be simultaneously obtained after separation by non-denaturing 2-DE, detection by negative staining and transferring to resins.

  4. Effect of bioactive aldehydes on gelatin properties

    Directory of Open Access Journals (Sweden)

    I. P. Krysyuk

    2015-04-01

    Full Text Available Bioactive aldehydes are among main factors of proteins postsynthetic modifications, which are the cause and consequence of many diseases. Comparative study of some aldehydes modifying action on gelatin was carried out in vitro. Gelatin samples (20 mM were incubated with: ribose, deoxyribose, glyoxal, methylglyoxal, formaldehyde, acrolein (20 mM each and their combinations in 0.1 M Na-phosphate buffer (pH 7.4 containing 0.02% sodium azide at 37 °C in the dark for 30 days. We investigated the fluorescent properties of these samples and their molecular weight distribution by electrophoresis. It has been revealed that formed adducts had different fluorescence spectra. According to fluorescence intensity these aldehydes were put in order: formaldehyde < methylglyoxal < acrolein < ribose < deoxy­ribose < glyoxal. The electrophoresis results showed fragments of gelatin molecular weight redistribution. By this index, the aldehydes rating was as follows: ribose < deoxyribose < acrolein < glyoxal < formaldehyde < methylglyoxal. Comparison of these two ratings indicates that aldehydes with a lower ability to form fluorescent adducts have higher abili­ty to form intermolecular crosslinks. Therefore, the traditional clinical fluorescent test of a patients’ skin surface for collagen crosslinks determination has to be verified by other tests for proteins postsynthetic modifications.

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

    Science.gov (United States)

    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

  6. [EFFECT OF BIOACTIVE ALDEHYDES ON GELATIN PROPERTIES].

    Science.gov (United States)

    Krysyuk, I P; Dzvonkevych, N D; Volodina, T T; Popova, N N; Shandrenko, S G

    2015-01-01

    Bioactive aldehydes are among main factors of proteins postsynthetic modifications, which are the cause and consequence of many diseases. Comparative study of some aldehydes modifying action on gelatin was carried out in vitro. Gelatin samples (20 mM) were incubated with: ribose, deoxyribose, glyoxal, methylglyoxal, formaldehyde, acrolein (20 mM each) and their combinations in 0.1 M Naphosphate buffer (pH 7.4) containing 0.02% sodium azide at 37 °C in the dark for 30 days. We investigated the fluorescent properties of these samples and their molecular weight distribution by electrophoresis. It has been revealed that formed adducts had different fluorescence spectra. According to fluorescence intensity these aldehydes were put in order: formaldehyde acrolein acrolein test of a patients' skin surface for collagen crosslinks determination has to be verified by other tests for proteins postsynthetic modifications.

  7. Colorimetric Recognition of Aldehydes and Ketones.

    Science.gov (United States)

    Li, Zheng; Fang, Ming; LaGasse, Maria K; Askim, Jon R; Suslick, Kenneth S

    2017-08-07

    A colorimetric sensor array has been designed for the identification of and discrimination among aldehydes and ketones in vapor phase. Due to rapid chemical reactions between the solid-state sensor elements and gaseous analytes, distinct color difference patterns were produced and digitally imaged for chemometric analysis. The sensor array was developed from classical spot tests using aniline and phenylhydrazine dyes that enable molecular recognition of a wide variety of aliphatic or aromatic aldehydes and ketones, as demonstrated by hierarchical cluster, principal component, and support vector machine analyses. The aldehyde/ketone-specific sensors were further employed for differentiation among and identification of ten liquor samples (whiskies, brandy, vodka) and ethanol controls, showing its potential applications in the beverage industry. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. An Ultrasensitive Plasmonic Nanosensor for Aldehydes.

    Science.gov (United States)

    Li, Meng; Shi, Lei; Xie, Tao; Jing, Chao; Xiu, Guangli; Long, Yi-Tao

    2017-02-24

    Glucose is the most common but important aldehyde, and it is necessary to create biosensors with high sensitivity and anti-interference to detect it. Under the existence of silver ions and aldehyde compounds, single gold nanoparticles and freshly formed silver atoms could respectively act as core and shell, which finally form a core-shell structure. By observing the reaction between glucose and Tollens' reagent, metallic silver was found to be reduced on the surface of gold nanoparticles and formed Au@Ag nanoparticles that lead to a direct wavelength shift. Based on this principle and combined with in situ plasmon resonance scattering spectra, a plasmonic nanosensor was successfully applied in identifying aldehyde compounds with excellent sensitivity and specificity. This ultrasensitive sensor was successfully further utilized to detect blood glucose in mice serum samples, exhibiting good anti-interference ability and great promise for future clinical application.

  9. Contribution of ALDH1A1 isozyme to detoxification of aldehydes present in food products.

    Science.gov (United States)

    Sołobodowska, Sylwia; Giebułtowicz, Joanna; Wolinowska, Renata; Wroczyński, Piotr

    2012-01-01

    Even though food awareness is so developed and more and more people pay attention to what their diet is composed of, it is not possible to exclude all potentially dangerous substances present in our diet. One group of such compounds may be aldehydes as several studies indicate that they can be mutagenic, carcinogenic, genotoxic and cytotoxic. These relatively reactive organic molecules are natural constituents of food. They are also extensively used by food industry as additives giving aroma and taste. Fortunately many enzyme systems were developed to protect us against these toxic compounds, one of which is aldehyde dehydrogenase enzyme superfamily. As mouth is the first part of digestive system it seems crucial for detoxifying toxic substances introduced with our diet. The only ALDH isozyme present in saliva is ALDH3A1, which has very high affinity towards aromatic aldehydes commonly found in food. However, because of hyposalivation, which is not uncommon nowadays, the effectiveness of this barrier can be drastically diminished. As another member of this enzyme family, isozyme ALDH1A1 is also present in digestive system its possible contribution to detoxification of "food" aldehydes was addressed. Kinetic parameters (Km, Vmax) of recombinant ALDH1A1 towards several aliphatic and aromatic aldehydes occurring in food products (vanillin, citral, furfural, cinnamaldehyde, anisaldehyde, benzaldehyde and trans-hexenal) were determined by measuring the increase of NADH fluorescence after adding various concentrations of aldehyde substrates. Rates were used to construct the Lineweaver-Burk plot from which Km and Vmax (measured relative to that of benzaldehyde which was assigned the value of 100) values were calculated. The following results were obtained: 0.04 +/- 0.06 microM and 277 +/- 81 for anisaldehyde, 0.86 +/- 0.03 mciroM and 50 +/- 3 for vanillin, 0.18 +/- 0.05 mciroM and 93 +/- 9 for trans-2-hexenal, 0.17 +/- 0.03 microM and 201 +/- 32 for cinnamaldehyde, 5

  10. Effect of bioactive aldehydes on gelatin properties

    OpenAIRE

    I. P. Krysyuk; N. D. Dzvonkevych; T. T. Volodina; N. N. Popova; S. G. Shandrenko

    2015-01-01

    Bioactive aldehydes are among main factors of proteins postsynthetic modifications, which are the cause and consequence of many diseases. Comparative study of some aldehydes modifying action on gelatin was carried out in vitro. Gelatin samples (20 mM) were incubated with: ribose, deoxyribose, glyoxal, methylglyoxal, formaldehyde, acrolein (20 mM each) and their combinations in 0.1 M Na-phosphate buffer (pH 7.4) containing 0.02% sodium azide at 37 °C in the dark for 30 days. We investigated t...

  11. Palladium complexes of pyrrole-2-aldehyde thiosemicarbazone ...

    Indian Academy of Sciences (India)

    Vol. 126, No. 5, September 2014, pp. 1547–1555. c Indian Academy of Sciences. Palladium complexes of pyrrole-2-aldehyde thiosemicarbazone: Synthesis, structure and spectral properties. PIYALI PAUL and SAMARESH BHATTACHARYA. ∗. Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, ...

  12. Initial steps of the peroxidase-catalyzed polymerization of coniferyl alcohol and/or sinapyl aldehyde: capillary zone electrophoresis study of pH effect.

    Science.gov (United States)

    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.

  13. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for the...

  14. Studies on lipoamide dehydrogenase

    NARCIS (Netherlands)

    Benen, J.A.E.

    1992-01-01

    At the onset of the investigations described in this thesis progress was being made on the elucidation of the crystal structure of the Azotobactervinelandii lipoamide dehydrogenase. Also the gene encoding this enzyme was cloned in our laboratory. By this, a

  15. Studies on lipoamide dehydrogenase

    NARCIS (Netherlands)

    Visser, J.

    1969-01-01

    Gel-filtration, ultracentrifugation and sucrose density gradient centrifugation demonstrated differences in physico-chemical properties of holoenzyme and apoenzyme of lipoamide dehydrogenase. The native apoenzyme has a mol.wt. of approx. 52,000 which is half that of the native holoenzyme. The

  16. Aldehyde-induced xanthine oxidase activity in raw milk.

    Science.gov (United States)

    Steffensen, Charlotte L; Andersen, Henrik J; Nielsen, Jacob H

    2002-12-04

    In the present study, the aldehyde-induced pro-oxidative activity of xanthine oxidase was followed in an accelerated raw milk system using spin-trap electron spin resonance (ESR) spectroscopy. The aldehydes acetaldehyde, propanal, hexanal, trans-2-hexenal, trans-2-heptenal, trans-2-nonenal, and 3-methyl-2-butenal were all found to initiate radical reactions when added to milk. Formation of superoxide through aldehyde-induced xanthine oxidase activity is suggested as the initial reaction, as all tested aldehydes were shown to trigger superoxide formation in an ultrahigh temperature (UHT) milk model system with added xanthine oxidase. It was found that addition of aldehydes to milk initially increased the ascorbyl radical concentration with a subsequent decay due to ascorbate depletion, which renders the formation of superoxide in milk with added aldehyde. The present study shows for the first time potential acceleration of oxidative events in milk through aldehyde-induced xanthine oxidase activity.

  17. Aldehyde decarbonylation catalysis under mild conditions

    Energy Technology Data Exchange (ETDEWEB)

    Beck, C.M.; Rathmill, S.E.; Park, Y.J.; Chen, J.; Crabtree, R.H.; Liable-Sands, L.M.; Rheingold, A.L.

    1999-12-06

    Reaction of [RhCl(NBD)]{sub 2} with 2.0 equiv of triphos (triphos = bis(2-diphenylphosphinoethyl)phenylphosphine; NBD = bicyclo[2.2.1]hepta-2,5-diene) in THF solution at room temperature affords [Rh(NBD)(triphos)][Cl] (4a), which was isolated as [Rh(NBD)(triphos)][SbF{sub 6}] (4b) in 67% yield. Treatment of 4b with aqueous formaldehyde in THF solution at 80 C forms [Rh(CO)(triphos)][SbF{sub 6}] (2a), which reversibly binds a second equivalent of CO{sub (g)} to give [Rh(CO){sub 2}(triphos)][SbF{sub 6}] (2b). The complex [Rh(CO)(triphos)][SbF{sub 6}] has been found to be an effective aldehyde decarbonylation catalyst for primary and aryl aldehydes at temperatures as low as that of refluxing dioxane, with little or no undesirable side products resulting from {beta} elimination or radical rearrangement.

  18. Characterization and Targeting of the Aldehyde Dehydrogenase Subpopulation in Ovarian Cancer

    Science.gov (United States)

    2013-07-01

    pancreatic cancer. Pancreas. 2008 Oct;37(3):275-81. 28. Hu D, Wang X, Mao Y, Zhou L. Identification of CD105 (endoglin)-positive stem-like cells in...Women who have breaks in ovulation due to pregnancy and breast- feeding have lower risk of disease.19,20 Moreover, women who take oral con

  19. Characterization and Targeting of the Aldehyde Dehydrogenase Subpopulation in Ovarian Cancer

    Science.gov (United States)

    2016-10-01

    Hanks’ balanced salt solution (HBSS; Gibco) and injected intraperitoneally into NOD- SCIDmice in limiting dilutions . Mice were followed for 1 year or...malignant human colonic stem cells (SC) and tracks SC overpopulation during colon tumorigenesis. Cancer Res 2009;69:3382–9. 16. Carpentino JE, HynesMJ...peroxidase activity was quenched with 3% hydrogen peroxide solution in methanol for 15 minutes. Sections were blocked with CytoQ immune diluent and

  20. Characterization and Targeting of the Aldehyde Dehydrogenase Subpopulation in Ovarian Cancer

    Science.gov (United States)

    2012-07-01

    but increased expression specific to tumor cells in our laser-microdis- sected tissues suggest that it may play a role in tumor cell chemoresistance...Interests Family activities Wife Donna; Kids Sydney, Nicholson, and Jackson Sports / Crosstraining / Triathlon Hiking / Camping Religion / Philosophy / History

  1. Characterization and Targeting of the Aldehyde Dehydrogenase Subpopulation in Ovarian Cancer

    Science.gov (United States)

    2014-07-01

    modification; however, for publication of PCNA figures, contrast was enhanced to an entire image by using the "Auto Contrast" tool in Photoshop to avoid bias...Page Introduction…………………………………………………………….………..….. 1 Body ...provide the opportunity to more fully characterize which cells are mediating survival of primary therapy. BODY : Task 1: Determine

  2. Characterization and Targeting of the Aldehyde Dehydrogenase Subpopulation in Ovarian Cancer

    Science.gov (United States)

    2015-07-01

    Sharp BA, Underwood PB. Cancer patients’ satisfaction with physicians: PMH-SPQ-MD questionnaire results. Am J Obstet Gynecol 188(5):1177-1179, 2003...outcome in uterine cancer : Molecular explanations. Proceedings of the 39th Annual Society of Gynecologic Oncologists Meeting, 2008. Page 16 Revised 8/20...basis for the impact of EphA2 overexpression on clinical outcome in uterine cancer Proceedings of the American Association of Cancer Research, 2008

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

    Science.gov (United States)

    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.

  4. The activity of the artemisinic aldehyde Δ11(13) reductase promoter is important for artemisinin yield in different chemotypes of Artemisia annua L.

    Science.gov (United States)

    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.

  5. [Malate dehydrogenase and lactate dehydrogenase in trematodes and turbellarians].

    Science.gov (United States)

    Vykhrestiuk, N P; Burenina, E A; Iarygina, G V

    1986-01-01

    Studies have been made on the activity and properties of malate and lactate dehydrogenases from the cattle rumen trematodes Eurytrema pancreaticum, Calicophoron ijimai and the turbellarian Phagocata sibirica which has a common free-living ancestor with the trematodes. All the species studied have a highly active malate dehydrogenase, its activity in the reaction of reducing oxaloacetate being 6-14 times higher than in the reaction of malate oxidation. The affinity of malate dehydrogenase to oxaloacetate was found to be higher than that to malate. The activity of lactate dehydrogenase (reducing the pyruvate) was lower than the activity of malate dehydrogenase, the difference being 50 times for C. ijimai, 4 times for E. pancreaticum and 10 times for P. sibirica.

  6. Structure-oriented substrate specificity engineering of aldehyde-deformylating oxygenase towards aldehydes carbon chain length.

    Science.gov (United States)

    Bao, Luyao; Li, Jian-Jun; Jia, Chenjun; Li, Mei; Lu, Xuefeng

    2016-01-01

    Aldehyde-deformylating oxygenase (ADO) is an important enzyme involved in the biosynthetic pathway of fatty alk(a/e)nes in cyanobacteria. However, ADO exhibits quite low chain-length specificity with respect to the substrates ranging from C4 to C18 aldehydes, which is not suitable for producing fuels with different properties or different chain lengths. Based on the crystal structures of cADOs (cyanobacterial ADO) with substrate analogs bound, some amino acids affecting the substrate specificity of cADO were identified, including the amino acids close to the aldehyde group and the hydrophobic tail of the substrate and those along the substrate channel. Using site-directed mutagenesis, selected amino acids were replaced with bulky ones introducing steric hindrance to the binding pocket via large functional groups. All mutants were overexpressed, purified and kinetically characterized. All mutants, except F87Y, displayed dramatically reduced activity towards C14,16,18 aldehydes. Notably, the substrate preferences of some mutants towards different chain-length substrates were enhanced: I24Y for n-heptanal, I27F for n-decanal and n-dodecanal, V28F for n-dodecanal, F87Y for n-decanal, C70F for n-hexanal, A118F for n-butanal, A121F for C4,6,7 aldehydes, V184F for n-dodecanal and n-decanal, M193Y for C6-10 aldehydes and L198F for C7-10 aldehydes. The impact of the engineered cADO mutants on the change of the hydrocarbon profile was demonstrated by co-expressing acyl-ACP thioesterase BTE, fadD and V184F in E. coli, showing that n-undecane was the main fatty alkane. Some amino acids, which can control the chain-length selectivity of substrates of cADO, were identified. The substrate specificities of cADO were successfully changed through structure-guided protein engineering, and some mutants displayed different chain-length preference. The in vivo experiments of V184F in genetically engineered E. coli proved the importance of engineered cADOs on the distribution of the

  7. Genetics Home Reference: lactate dehydrogenase deficiency

    Science.gov (United States)

    ... this condition: lactate dehydrogenase-A deficiency (sometimes called glycogen storage disease XI) and lactate dehydrogenase-B deficiency. People with ... Resources Genetic Testing (2 links) Genetic Testing Registry: Glycogen storage disease XI Genetic Testing Registry: Lactate dehydrogenase B deficiency ...

  8. Peptide aldehyde inhibitors of bacterial peptide deformylases.

    Science.gov (United States)

    Durand, D J; Gordon Green, B; O'Connell, J F; Grant, S K

    1999-07-15

    Bacterial peptide deformylases (PDF, EC 3.5.1.27) are metalloenzymes that cleave the N-formyl groups from N-blocked methionine polypeptides. Peptide aldehydes containing a methional or norleucinal inhibited recombinant peptide deformylase from gram-negative Escherichia coli and gram-positive Bacillus subtilis. The most potent inhibitor was calpeptin, N-CBZ-Leu-norleucinal, which was a competitive inhibitor of the zinc-containing metalloenzymes, E. coli and B. subtilis PDF with Ki values of 26.0 and 55.6 microM, respectively. Cobalt-substituted E. coli and B. subtilis deformylases were also inhibited by these aldehydes with Ki values for calpeptin of 9.5 and 12.4 microM, respectively. Distinct spectral changes were observed upon binding of calpeptin to the Co(II)-deformylases, consistent with the noncovalent binding of the inhibitor rather than the formation of a covalent complex. In contrast, the chelator 1,10-phenanthroline caused the time-dependent inhibition of B. subtilis Co(II)-PDF activity with the loss of the active site metal. The fact that calpeptin was nearly equipotent against deformylases from both gram-negative and gram-positive bacterial sources lends further support to the idea that a single deformylase inhibitor might have broad-spectrum antibacterial activity. Copyright 1999 Academic Press.

  9. Redox Balance in Lactobacillus reuteri DSM20016: Roles of Iron-Dependent Alcohol Dehydrogenases in Glucose/ Glycerol Metabolism.

    Science.gov (United States)

    Chen, Lu; Bromberger, Paul David; Nieuwenhuiys, Gavin; Hatti-Kaul, Rajni

    2016-01-01

    Lactobacillus reuteri, a heterofermentative bacterium, metabolizes glycerol via a Pdu (propanediol-utilization) pathway involving dehydration to 3-hydroxypropionaldehyde (3-HPA) followed by reduction to 1,3-propandiol (1,3-PDO) with concomitant generation of an oxidized cofactor, NAD+ that is utilized to maintain cofactor balance required for glucose metabolism and even for oxidation of 3-HPA by a Pdu oxidative branch to 3-hydroxypropionic acid (3-HP). The Pdu pathway is operative inside Pdu microcompartment that encapsulates different enzymes and cofactors involved in metabolizing glycerol or 1,2-propanediol, and protects the cells from the toxic effect of the aldehyde intermediate. Since L. reuteri excretes high amounts of 3-HPA outside the microcompartment, the organism is likely to have alternative alcohol dehydrogenase(s) in the cytoplasm for transformation of the aldehyde. In this study, diversity of alcohol dehydrogenases in Lactobacillus species was investigated with a focus on L. reuteri. Nine ADH enzymes were found in L. reuteri DSM20016, out of which 3 (PduQ, ADH6 and ADH7) belong to the group of iron-dependent enzymes that are known to transform aldehydes/ketones to alcohols. L. reuteri mutants were generated in which the three ADHs were deleted individually. The lagging growth phenotype of these deletion mutants revealed that limited NAD+/NADH recycling could be restricting their growth in the absence of ADHs. Notably, it was demonstrated that PduQ is more active in generating NAD+ during glycerol metabolism within the microcompartment by resting cells, while ADH7 functions to balance NAD+/NADH by converting 3-HPA to 1,3-PDO outside the microcompartment in the growing cells. Moreover, evaluation of ADH6 deletion mutant showed strong decrease in ethanol level, supporting the role of this bifuctional alcohol/aldehyde dehydrogenase in ethanol production. To the best of our knowledge, this is the first report revealing both internal and external recycling

  10. Reduction of Aldehydes Using Sodium Borohydride under Ultrasonic Irradiation

    Directory of Open Access Journals (Sweden)

    Maulidan Firdaus

    2016-08-01

    Full Text Available A simple, energy efficient, and relatively quick synthetic procedure for the reduction of aldehydes under ultrasonic irradiation is reported. Satisfactorily isolated yields (71-96% were achieved confirming that the preparation of alcohol by aldehyde reduction is possible in green and sustainable fashion.

  11. The oxidation of the aldehyde groups in dialdehyde starch

    NARCIS (Netherlands)

    Haaksman, I.K.; Besemer, A.C.; Jetten, J.M.; Timmermans, J.W.; Slaghek, T.M.

    2006-01-01

    This paper describes the difference in relative reactivity of the aldehyde groups present in dialdehyde starch towards different oxidising agents. The oxidation of dialdehyde starch with peracetic acid and sodium bromide leads to only partial oxidation to give mono-aldehyde-carboxy starch, while

  12. A new method for the chemoselective reduction of aldehydes and ...

    Indian Academy of Sciences (India)

    Abstract. A chemoselective Meerwein–Ponndorf–Verley reduction process of various aliphatic and allylic α,β-unsaturated aldehydes and ketones is described. This chemoselective reduction is catalysed by boron tri- isopropoxide B(Oi Pr)3. Kinetics of reduction of aldehydes and ketones to corresponding alcohols were also.

  13. Reduction of Aldehydes and Ketones by Sodium Dithionite

    NARCIS (Netherlands)

    Vries, Johannes G. de; Kellogg, Richard M.

    1980-01-01

    Conditions have been developed for the effective reduction of aldehydes and ketones by sodium dithionite, Na2S2O4. Complete reduction of simple aldehydes and ketones can be achieved with excess Na2S2O4 in H2O/dioxane mixtures at reflux temperature. Some aliphatic ketones, for example, pentanone and

  14. A new method for the chemoselective reduction of aldehydes and ...

    Indian Academy of Sciences (India)

    A chemoselective Meerwein-Ponndorf-Verley reduction process of various aliphatic and allylic ,-unsaturated aldehydes and ketones is described. This chemoselective reduction is catalysed by boron triisopropoxide B(OPr)3. Kinetics of reduction of aldehydes and ketones to corresponding alcohols were also examined ...

  15. Threshold responses in cinnamic-aldehyde-sensitive subjects

    DEFF Research Database (Denmark)

    Johansen, J D; Andersen, K E; Rastogi, Suresh Chandra

    1996-01-01

    Cinnamic aldehyde is an important fragrance material and contact allergen. The present study was performed to provide quantitative data on the eliciting capacity of cinnamic aldehyde, to be considered in assessment of clinical relevance and health hazard. The skin response to serial dilution patc...

  16. Emissions of odorous aldehydes from an alkyd paint

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J.C.S. [Environmental Protection Agency, Research Triangle Park, NC (United States); Guo, Z. [Acurex Environmental Corp., Research Triangle Park, NC (United States)

    1998-12-31

    Odorous aldehyde emissions from a commonly used alkyd paint were measured and characterized. Initial formulation analysis indicated no measurable aldehydes in the liquid paint. However, small environmental chamber tests showed that, for each gram of the alkyd paint applied, more than 2 mg of aldehydes (mainly hexanal) were emitted during the curing (drying) period. The emission profiles of Aldehydes were very different from those of other volatile organic compounds such as alkanes and aromatics. Since no measurable aldehydes were found in the original point, it is suspected that the aldehydes emitted were produced by autoxidation of the unsaturated fatty acid esters in the alkyd resins. It was found that the hexanal emission rate can be simulated by a mathematical model assuming that the autoxidation process was controlled by a consecutive first-order reaction mechanism. The mathematical model was used to predict the indoor air hexanal concentrations for a typical application of the alkyd paint tested. The result indicated that the aldehyde emissions can result in prolonged (several days) exposure risk to occupants.

  17. Comparison of bioactive aldehydes modifying action on human albumin

    OpenAIRE

    I. P. Krysiuk; A. J. Knaub; S. G. Shandrenko

    2014-01-01

    Protein’s postsynthetic modifications are a cause and a consequence of many diseases. Endogenous aldehydes are one of the main factors of these modifications formation. The human albumin’s modification under some aldehydes influence in in vitro experiment has been investigated. Human albumin (20 mM) was incubated with following aldehydes: ribose, glyoxal, methylglyoxal and formaldehyde (20 mM each) and their combinations in 0.1 M Na-phosphate buffer (pH 7.4) with 0.02% sodium azide at 37 °C i...

  18. Benzyllithiums bearing aldehyde carbonyl groups. A flash chemistry approach.

    Science.gov (United States)

    Nagaki, Aiichiro; Tsuchihashi, Yuta; Haraki, Suguru; Yoshida, Jun-ichi

    2015-07-14

    Reductive lithiation of benzyl halides bearing aldehyde carbonyl groups followed by reaction with subsequently added electrophiles was successfully accomplished without affecting the carbonyl groups by taking advantage of short residence times in flow microreactors.

  19. Silver-catalyzed synthesis of amides from amines and aldehydes

    Science.gov (United States)

    Madix, Robert J; Zhou, Ling; Xu, Bingjun; Friend, Cynthia M; Freyschlag, Cassandra G

    2014-11-18

    The invention provides a method for producing amides via the reaction of aldehydes and amines with oxygen adsorbed on a metallic silver or silver alloy catalyst. An exemplary reaction is shown in Scheme 1: (I), (II), (III). ##STR00001##

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

    Science.gov (United States)

    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.

  1. Aldehyde oxidase activity in fresh human skin.

    Science.gov (United States)

    Manevski, Nenad; Balavenkatraman, Kamal Kumar; Bertschi, Barbara; Swart, Piet; Walles, Markus; Camenisch, Gian; Schiller, Hilmar; Kretz, Olivier; Ling, Barbara; Wettstein, Reto; Schaefer, Dirk J; Pognan, Francois; Wolf, Armin; Litherland, Karine

    2014-12-01

    Human aldehyde oxidase (AO) is a molybdoflavoenzyme that commonly oxidizes azaheterocycles in therapeutic drugs. Although high metabolic clearance by AO resulted in several drug failures, existing in vitro-in vivo correlations are often poor and the extrahepatic role of AO practically unknown. This study investigated enzymatic activity of AO in fresh human skin, the largest organ of the body, frequently exposed to therapeutic drugs and xenobiotics. Fresh, full-thickness human skin was obtained from 13 individual donors and assayed with two specific AO substrates: carbazeran and zoniporide. Human skin explants from all donors metabolized carbazeran to 4-hydroxycarbazeran and zoniporide to 2-oxo-zoniporide. Average rates of carbazeran and zoniporide hydroxylations were 1.301 and 0.164 pmol⋅mg skin(-1)⋅h(-1), resulting in 13 and 2% substrate turnover, respectively, after 24 hours of incubation with 10 μM substrate. Hydroxylation activities for the two substrates were significantly correlated (r(2) = 0.769), with interindividual variability ranging from 3-fold (zoniporide) to 6-fold (carbazeran). Inclusion of hydralazine, an irreversible inhibitor of AO, resulted in concentration-dependent decrease of hydroxylation activities, exceeding 90% inhibition of carbazeran 4-hydroxylation at 100 μM inhibitor. Reaction rates were linear up to 4 hours and well described by Michaelis-Menten enzyme kinetics. Comparison of carbazeran and zoniporide hydroxylation with rates of triclosan glucuronidation and sulfation and p-toluidine N-acetylation showed that cutaneous AO activity is comparable to tested phase II metabolic reactions, indicating a significant role of AO in cutaneous drug metabolism. To our best knowledge, this is the first report of AO enzymatic activity in human skin. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  2. Alcohol dehydrogenases in Acinetobacter sp. strain HO1-N: role in hexadecanse and hexadecanol metabolism

    International Nuclear Information System (INIS)

    Singer, M.E.; Finnerty, W.R.

    1985-01-01

    Multiple alcohol dehydrogenases (ADH) were demonstrated in Acinetobacter sp. strain HO1-N. ADH-A and ADH-B were distinguished on the basis of electrophoretic mobility, pyridine nucleotide cofactor requirement, and substrate specificity. ADH-A is a soluble, NAD-linked, inducible ethanol dehydrogenase (EDH). An ethanol-negative mutant (Eth1) was isolated which contained 6.5% of wild-type EDH activity and was deficient in ADH-A. Eth1 exhibited normal growth on hexadecane and hexadecanol. A second ethanol-negative mutant (Eth3) was acetaldehyde dehydrogenase (ALDH) deficient, having 12.5% of wild-type ALDH activity. Eth3 had threefold-higher EDH activity than the wild-type strain. ALDH is a soluble, NAD-linked, ethanol-inducible enzyme. Eth3 exhibited normal growth on hexadecane, hexadecanol, and fatty aldehyde. ADH-B is soluble, constitutive, NADP-linked ADH which was active with medium-chain-length alcohols. Hexadecanol dehydrogenase (HDH), a soluble and membrane-bound, NAD-linked ADH, was induced 5- to 11-fold by growth on hexadecane or hexadecanol. HDH was distinct from ADH-A and ADH-B. NAD-linked HDH appears to possess a functional role in hexadecane and hexadecanol dissimilation

  3. Genetics Home Reference: dihydropyrimidine dehydrogenase deficiency

    Science.gov (United States)

    ... 5-fluorouracil and capecitabine. These drugs are not broken down efficiently by people with dihydropyrimidine dehydrogenase deficiency ... of this enzyme. Because fluoropyrimidine drugs are also broken down by the dihydropyrimidine dehydrogenase enzyme, deficiency of ...

  4. Novel dehydrogenase catalyzes oxidative hydrolysis of carbon-nitrogen double bonds for hydrazone degradation.

    Science.gov (United States)

    Itoh, Hideomi; Suzuta, Tetsuya; Hoshino, Takayuki; Takaya, Naoki

    2008-02-29

    Hydrazines and their derivatives are versatile artificial and natural compounds that are metabolized by elusive biological systems. Here we identified microorganisms that assimilate hydrazones and isolated the yeast, Candida palmioleophila MK883. When cultured with adipic acid bis(ethylidene hydrazide) as the sole source of carbon, C. palmioleophila MK883 degraded hydrazones and accumulated adipic acid dihydrazide. Cytosolic NAD+- or NADP+-dependent hydrazone dehydrogenase (Hdh) activity was detectable under these conditions. The production of Hdh was inducible by adipic acid bis(ethylidene hydrazide) and the hydrazone, varelic acid ethylidene hydrazide, under the control of carbon catabolite repression. Purified Hdh oxidized and hydrated the C=N double bond of acetaldehyde hydrazones by reducing NAD+ or NADP+ to produce relevant hydrazides and acetate, the latter of which the yeast assimilated. The deduced amino acid sequence revealed that Hdh belongs to the aldehyde dehydrogenase (Aldh) superfamily. Kinetic and mutagenesis studies showed that Hdh formed a ternary complex with the substrates and that conserved Cys is essential for the activity. The mechanism of Hdh is similar to that of Aldh, except that it catalyzed oxidative hydrolysis of hydrazones that requires adding a water molecule to the reaction catalyzed by conventional Aldh. Surprisingly, both Hdh and Aldh from baker's yeast (Ald4p) catalyzed the Hdh reaction as well as aldehyde oxidation. Our findings are unique in that we discovered a biological mechanism for hydrazone utilization and a novel function of proteins in the Aldh family that act on C=N compounds.

  5. Contribution of ozone to airborne aldehyde formation in Paris homes.

    Science.gov (United States)

    Rancière, Fanny; Dassonville, Claire; Roda, Célina; Laurent, Anne-Marie; Le Moullec, Yvon; Momas, Isabelle

    2011-09-15

    Indoor aldehydes may result from ozone-initiated chemistry, mainly documented by experimental studies. As part of an environmental investigation included in the PARIS birth cohort, the aim of this study was to examine ozone contribution to airborne aldehyde formation in Paris homes. Formaldehyde, acetaldehyde and hexaldehyde levels, as well as styrene, nitrogen dioxide and nicotine concentrations, comfort parameters and carbon dioxide levels, were measured twice during the first year of life of the babies. Ambient ozone concentrations were collected from the closest background station of the regional air monitoring network. Traffic-related nitrogen oxide concentrations in front of the dwellings were estimated by an air pollution dispersion model. Home characteristics and families' way of life were described by questionnaires. Stepwise multiple linear regression models were used to link aldehyde levels with ambient ozone concentrations and a few aldehyde precursors involved in oxidation reactions, adjusting for other indoor aldehyde sources, comfort parameters and traffic-related nitrogen oxides. A 4 and 11% increase in formaldehyde and hexaldehyde levels was pointed out when 8-hour ozone concentrations increased by 20 μg/m(3). The influence of potential precursors such as indoor styrene level and frequent use of air fresheners, containing unsaturated volatile organic compounds as terpenes, was also found. Thus, our results suggest that ambient ozone can significantly impact indoor air quality, especially with regard to formaldehyde and hexaldehyde levels. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Comparison of bioactive aldehydes modifying action on human albumin

    Directory of Open Access Journals (Sweden)

    I. P. Krysiuk

    2014-04-01

    Full Text Available Protein’s postsynthetic modifications are a cause and a consequence of many diseases. Endogenous aldehydes are one of the main factors of these modifications formation. The human albumin’s modification under some aldehydes influence in in vitro experiment has been investigated. Human albumin (20 mM was incubated with following aldehydes: ribose, glyoxal, methylglyoxal and formaldehyde (20 mM each and their combinations in 0.1 M Na-phosphate buffer (pH 7.4 with 0.02% sodium azide at 37 °C in the dark for up to 30 days. We have determined the fluorescent properties of the samples, the content of protein’s carbonyl groups and the redistribution of protein’s molecular weight. The following ratings of aldehydes from the lowest to the highest effect have been obtained. Fluo­rescent albumin adducts formation: formaldehyde, methylglyoxal, ribose, glyoxal; carbonylation of the protein: ribose, formaldehyde, glyoxal, methyl­glyoxal; polymerization of albumin – the formation of intermolecular crosslinks: ribose, methylglyoxal, glyoxal, formaldehyde. The results indicate that these aldehydes have different capability for protein’s modifications. For example, formaldehyde, having the lowest ability to form fluorescent adducts, shows the highest ability to form protein’s intermolecular crosslinks. Therefore, methods and parame­ters in order to evaluate the protein postsynthetic modification intensity have to be chosen correctly according to carbonyl stress peculiarity in order to evaluate the protein’s postsynthetic modification intensity.

  7. [Comparison of bioactive aldehydes modifying action on human albumin].

    Science.gov (United States)

    Krysiuk, I P; Knaub, A Ia; Shandrenko, S H

    2014-01-01

    Protein's postsynthetic modifications are a cause and a consequence of many diseases. Endogenous aldehydes are one of the main factors of these modifications formation. The human albumin's modification under some aldehydes influence in in vitro experiment has been investigated. Human albumin (20 mM) was incubated with following aldehydes: ribose, glyoxal, methylglyoxal and formaldehyde (20 mM each) and their combinations in 0.1 M Na-phosphate buffer (pH 7.4) with 0.02% sodium azide at 37 degrees C in the dark for up to 30 days. We have determined the fluorescent properties of the samples, the content of protein's carbonyl groups and the redistribution of protein's molecular weight. The following ratings of aldehydes from the lowest to the highest effect have been obtained. Fluorescent albumin adducts formation: formaldehyde, methylglyoxal, ribose, glyoxal; carbonylation of the protein: ribose, formaldehyde, glyoxal, methylglyoxal; polymerization of albumin--the formation of intermolecular crosslinks: ribose, methylglyoxal, glyoxal, formaldehyde. The results indicate that these aldehydes have different capability for protein's modifications. For example, formaldehyde, having the lowest ability to form fluorescent adducts, shows the highest ability to form protein's intermolecular crosslinks. Therefore, methods and parameters in order to evaluate the protein postsynthetic modification intensity have to be chosen correctly according to carbonyl stress peculiarity in order to evaluate the protein's postsynthetic modification intensity.

  8. Preparation of 1-C-glycosyl aldehydes by reductive hydrolysis.

    Science.gov (United States)

    Sipos, Szabolcs; Jablonkai, István

    2011-09-06

    Reductive hydrolysis of various protected glycosyl cyanides was carried out using DIBAL-H to form aldimine alane intermediates which were then hydrolyzed under mildly acidic condition to provide the corresponding aldehyde derivatives. While 1-C-formyl glycal and 2-deoxy glycosyl derivatives were stable during isolation and storage 1-C-glycosyl formaldehydes in the gluco, galacto and manno series were sensitive and decomposition occurred by 2-alkyloxy elimination. A one-pot method using N,N'-diphenylethylenediamine to trap these aldehydes in stable form was developed. Reductive hydrolysis of glycosyl cyanides offers valuable aldehyde building blocks in a convenient way which can be applied in the synthesis of complex C-glycosides. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. A novel NADPH-dependent aldehyde reductase gene from Vigna radiata confers resistance to the grapevine fungal toxin eutypine.

    Science.gov (United States)

    Guillén, P; Guis, M; Martínez-Reina, G; Colrat, S; Dalmayrac, S; Deswarte, C; Bouzayen, M; Roustan, J P; Fallot, J; Pech, J C; Latché, A

    1998-11-01

    Eutypine, 4-hydroxy-3-(3-methyl-3-butene-1-ynyl) benzyl aldehyde, is a toxin produced by Eutypa lata, the causal agent of eutypa dieback of grapevines. It has previously been demonstrated that tolerance of some cultivars to this disease was correlated with their capacity to convert eutypine to the corresponding alcohol, eutypinol, which lacks phytotoxicity. We have thus purified to homogeneity a protein from Vigna radiata that exhibited eutypine-reducing activity and have isolated the corresponding cDNA. This encodes an NADPH-dependent reductase of 36 kDa that we have named Vigna radiata eutypine-reducing enzyme (VR-ERE), based on the capacity of a recombinant form of the protein to reduce eutypine into eutypinol. The strongest homologies (86.8%) of VR-ERE at the amino acid level were found with CPRD14, a drought-inducible gene of unknown function, isolated from Vigna unguiculata and with an aromatic alcohol dehydrogenase (71.7%) from Eucalyptus gunnii. Biochemical characterization of VR-ERE revealed that a variety of compounds containing an aldehyde group can act as substrates. However, the highest affinity was observed with 3-substituted benzaldehydes. Expression of a VR-ERE transgene in Vitis vinifera cells cultured in vitro conferred resistance to the toxin. This discovery opens up new biotechnological approaches for the generation of grapevines resistant to eutypa dieback.

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

    Directory of Open Access Journals (Sweden)

    Ahmad-Faris Seman-Kamarulzaman

    Full Text Available 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

  11. Silver-Catalyzed Aldehyde Olefination Using Siloxy Alkynes.

    Science.gov (United States)

    Sun, Jianwei; Keller, Valerie A; Meyer, S Todd; Kozmin, Sergey A

    2010-03-20

    We describe the development of a silver-catalyzed carbonyl olefination employing electron rich siloxy alkynes. This process constitutes an efficient synthesis of trisubstituted unsaturated esters, and represents an alternative to the widely utilized Horner-Wadsworth-Emmons reaction. Excellent diastereoselectivities are observed for a range of aldehydes using either 1-siloxy-1-propyne or 1-siloxy-1-hexyne. This mild catalytic process also enables chemoselective olefination of aldehydes in the presence of either ester or ketone functionality. Furthermore, since no by-products are generated, this catalytic process is perfectly suited for development of sequential reactions that can be carried out in a single flask.

  12. Applicability of the theory of thermodynamic similarity to predict the enthalpies of vaporization of aliphatic aldehydes

    Science.gov (United States)

    Esina, Z. N.; Korchuganova, M. R.

    2015-06-01

    The theory of thermodynamic similarity is used to predict the enthalpies of vaporization of aliphatic aldehydes. The predicted data allow us to calculate the phase diagrams of liquid-vapor equilibrium in a binary water-aliphatic aldehyde system.

  13. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Use of distillates containing aldehydes. 24.183 Section 24.183 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... the fermentation of wine and then returned to the distilled spirits plant from which distillates were...

  14. INTERACTION OF ALDEHYDES DERIVED FROM LIPID PEROXIDATION AND MEMBRANE PROTEINS.

    Directory of Open Access Journals (Sweden)

    Stefania ePizzimenti

    2013-09-01

    Full Text Available A great variety of compounds are formed during lipid peroxidation of polyunsaturated fatty acids of membrane phospholipids. Among them, bioactive aldehydes, such as 4-hydroxyalkenals, malondialdehyde (MDA and acrolein, have received particular attention since they have been considered as toxic messengers that can propagate and amplify oxidative injury. In the 4-hydroxyalkenal class, 4-hydroxy-2-nonenal (HNE is the most intensively studied aldehyde, in relation not only to its toxic function, but also to its physiological role. Indeed, HNE can be found at low concentrations in human tissues and plasma and participates in the control of biological processes, such as signal transduction, cell proliferation and differentiation. Moreover, at low doses, HNE exerts an anti-cancer effect, by inhibiting cell proliferation, angiogenesis, cell adhesion and by inducing differentiation and/or apoptosis in various tumor cell lines. It is very likely that a substantial fraction of the effects observed in cellular responses, induced by HNE and related aldehydes, be mediated by their interaction with proteins, resulting in the formation of covalent adducts or in the modulation of their expression and/or activity. In this review we focus on membrane proteins affected by lipid peroxidation-derived aldehydes, under physiological and pathological conditions.

  15. The Reduction of Nitriles to Aldehydes: Applications of Raney Nickel ...

    African Journals Online (AJOL)

    NJD

    The three title reductant systems have significant advantages in generating aldehydes from nitriles. These include: the utilization of convenient hydrogen sources, namely, sodium hypophosphite monohydrate and formic acid, respectively, and of the relatively inexpensive Raney nickel and Raney (Ni/Al) alloy; the ...

  16. Reaction of benzoxasilocines with aromatic aldehydes: Synthesis of homopterocarpans

    Directory of Open Access Journals (Sweden)

    Rodríguez-García Ignacio

    2007-02-01

    Full Text Available Abstract Condensation of 2H-benzo[g][1,2]oxasilocines with aromatic aldehydes in the presence of boron trifluoride affords mixtures of cis/trans 2-phenyl-3-vinylchromans with moderate yields. These can be transformed into homopterocarpans, a synthetic group of substances homologous to the natural isoflavonoid pterocarpans.

  17. Changes in nonpolar aldehydes in bean cotyledons during ageing

    Czech Academy of Sciences Publication Activity Database

    Wilhelmová, Naděžda; Domingues, P.; Srbová, M.; Fuksová, H.; Wilhelm, J.

    2006-01-01

    Roč. 50, č. 4 (2006), s. 559-564 ISSN 0006-3134 R&D Projects: GA ČR GA522/03/0312 Institutional research plan: CEZ:AV0Z50380511 Keywords : Ageing * aldehydes * lipid peroxidation * lipofuscin-like pigments (LFP) Subject RIV: CE - Biochemistry Impact factor: 1.198, year: 2006

  18. Alcohol Dehydrogenase-1B (rs1229984) and Aldehyde Dehydrogenase-2 (rs671) Genotypes and Alcoholic Ketosis Are Associated with the Serum Uric Acid Level in Japanese Alcoholic Men.

    Science.gov (United States)

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

    2016-05-01

    To identify determinants of hyperuricemia in alcoholics. The serum uric acid (UA) levels of 1759 Japanese alcoholic men (≥40 years) were measured on their first visit or within 3 days after admission; ADH1B and ALDH2 genotyping on blood DNA samples were performed. Dipstick urinalyses for ketonuria and serum UA measurements were simultaneously performed for 621 men on their first visit. Serum UA levels of >416 μmol/l (7.0 mg/dl) and ≥535 μmol/l (9.0 mg/dl) were observed in 30.4 and 7.8% of the subjects, respectively. Ketonuria was positive in 35.9% of the subjects, and a multivariate analysis revealed that the ketosis level was positively associated with the UA level. The presence of the ADH1B*2 allele and the ALDH2*1/*1 genotype increased the odds ratio (OR; 95% confidence interval) among subjects with a high UA level of >416 μmol/l (vs. ≤416 μmol/l; 2.04 [1.58-2.65] and 1.48 [1.09-2.01], respectively) and those with a high UA level of ≥535 μmol/l (vs. ≤416 μmol/l; 2.29 [1.42-3.71] and 3.03 [1.51-6.08], respectively). The ADH1B*2 plus ALDH2*1/*1 combination yielded the highest ORs (2.86 [1.61-5.10] and 6.21 [1.49-25.88] for a UA level of >416 μmol/l and ≥535 μmol/l, respectively), compared with the ADH1B*1/*1 plus ALDH2*1/*2 combination. The presence of diabetes and the consumption of Japanese sake rather than beer were negatively associated with the UA levels. The faster metabolism of ethanol and acetaldehyde by the ADH1B*2 allele and ALDH2*1/*1 genotype and higher ketosis levels were associated with higher UA levels in alcoholics, while diabetes and the consumption of sake were negative determinants. © The Author 2015. Medical Council on Alcohol and Oxford University Press. All rights reserved.

  19. Alcohol dehydrogenase and aldehyde dehydrogenase gene polymorphisms, alcohol intake and the risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition study

    DEFF Research Database (Denmark)

    Ferrari, P.; McKay, J. D.; Jenab, M.

    2012-01-01

    populations.SUBJECTS/METHODS: A nested case-control study (1269 cases matched to 2107controls by sex, age, study centre and date of blood collection) was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) to evaluate the impact of rs1229984 (ADH1B), rs1573496 (ADH7...

  20. Redox Balance in Lactobacillus reuteri DSM20016: Roles of Iron-Dependent Alcohol Dehydrogenases in Glucose/ Glycerol Metabolism.

    Directory of Open Access Journals (Sweden)

    Lu Chen

    Full Text Available Lactobacillus reuteri, a heterofermentative bacterium, metabolizes glycerol via a Pdu (propanediol-utilization pathway involving dehydration to 3-hydroxypropionaldehyde (3-HPA followed by reduction to 1,3-propandiol (1,3-PDO with concomitant generation of an oxidized cofactor, NAD+ that is utilized to maintain cofactor balance required for glucose metabolism and even for oxidation of 3-HPA by a Pdu oxidative branch to 3-hydroxypropionic acid (3-HP. The Pdu pathway is operative inside Pdu microcompartment that encapsulates different enzymes and cofactors involved in metabolizing glycerol or 1,2-propanediol, and protects the cells from the toxic effect of the aldehyde intermediate. Since L. reuteri excretes high amounts of 3-HPA outside the microcompartment, the organism is likely to have alternative alcohol dehydrogenase(s in the cytoplasm for transformation of the aldehyde. In this study, diversity of alcohol dehydrogenases in Lactobacillus species was investigated with a focus on L. reuteri. Nine ADH enzymes were found in L. reuteri DSM20016, out of which 3 (PduQ, ADH6 and ADH7 belong to the group of iron-dependent enzymes that are known to transform aldehydes/ketones to alcohols. L. reuteri mutants were generated in which the three ADHs were deleted individually. The lagging growth phenotype of these deletion mutants revealed that limited NAD+/NADH recycling could be restricting their growth in the absence of ADHs. Notably, it was demonstrated that PduQ is more active in generating NAD+ during glycerol metabolism within the microcompartment by resting cells, while ADH7 functions to balance NAD+/NADH by converting 3-HPA to 1,3-PDO outside the microcompartment in the growing cells. Moreover, evaluation of ADH6 deletion mutant showed strong decrease in ethanol level, supporting the role of this bifuctional alcohol/aldehyde dehydrogenase in ethanol production. To the best of our knowledge, this is the first report revealing both internal and

  1. Unsaturated aldehydes as alkene equivalents in the Diels-Alder reaction

    DEFF Research Database (Denmark)

    Taarning, Esben; Madsen, Robert

    2008-01-01

    A one-pot procedure is described for using alpha,beta-unsaturated aldehydes as olefin equivalents in the Diels-Alder reaction. The method combines the normal electron demand cycloaddition with aldehyde dienophiles and the rhodium-catalyzed decarbonylation of aldehydes to afford cyclohexenes...

  2. Competitive inhibition of glutamate dehydrogenase reaction.

    Science.gov (United States)

    Choudhury, Rajarshi; Punekar, Narayan S

    2007-06-12

    Irrespective of their pyridine nucleotide specificity, all glutamate dehydrogenases share a common chemical mechanism that involves an enzyme bound 'iminoglutarate' intermediate. Three compounds, structurally related to this intermediate, were tested for the inhibition of purified NADP-glutamate dehydrogenases from two Aspergilli, as also the bovine liver NAD(P)-glutamate dehydrogenase. 2-Methyleneglutarate, closely resembling iminoglutarate, was a potent competitive inhibitor of the glutamate dehydrogenase reaction. This is the first report of a non-aromatic structure with a better glutamate dehydrogenase inhibitory potency than aryl carboxylic acids such as isophthalate. A suitably located 2-methylene group to mimic the iminium ion could be exploited to design inhibitors of other amino acid dehydrogenases.

  3. GRE2 from Scheffersomyces stipitis as an aldehyde reductase contributes tolerance to aldehyde inhibitors derived from lignocellulosic biomass

    Science.gov (United States)

    Scheffersomyces (Pichia) stipitis is one of the most promising yeasts for industrial bioethanol production from lignocellulosic biomass. S. stipitis is able to in situ detoxify aldehyde inhibitors [such as furfural and 5-hydroxymethylfurfural (HMF)] to less toxic corresponding alcohols. However, the...

  4. Human cord blood progenitors with high aldehyde dehydrogenase activity improve vascular density in a model of acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Creer Michael H

    2010-03-01

    Full Text Available Abstract Human stem cells from adult sources have been shown to contribute to the regeneration of muscle, liver, heart, and vasculature. The mechanisms by which this is accomplished are, however, still not well understood. We tested the engraftment and regenerative potential of human umbilical cord blood-derived ALDHhiLin-, and ALDHloLin- cells following transplantation to NOD/SCID or NOD/SCID β2m null mice with experimentally induced acute myocardial infarction. We used combined nanoparticle labeling and whole organ fluorescent imaging to detect human cells in multiple organs 48 hours post transplantation. Engraftment and regenerative effects of cell treatment were assessed four weeks post transplantation. We found that ALDHhiLin- stem cells specifically located to the site of injury 48 hours post transplantation and engrafted the infarcted heart at higher frequencies than ALDHloLin- committed progenitor cells four weeks post transplantation. We found no donor derived cardiomyocytes and few endothelial cells of donor origin. Cell treatment was not associated with any detectable functional improvement at the four week endpoint. There was, however, a significant increase in vascular density in the central infarct zone of ALDHhiLin- cell-treated mice, as compared to PBS and ALDHloLin- cell-treated mice. Conclusions Our data indicate that adult human stem cells do not become a significant part of the regenerating tissue, but rapidly home to and persist only temporarily at the site of hypoxic injury to exert trophic effects on tissue repair thereby enhancing vascular recovery.

  5. Expression of aldehyde dehydrogenase family 1, member A3 in glycogen trophoblast cells of the murine placenta.

    Science.gov (United States)

    Outhwaite, J E; Natale, B V; Natale, D R C; Simmons, D G

    2015-03-01

    Retinoic acid (RA) signaling is a well known regulator of trophoblast differentiation and placental development, and maternal decidual cells are recognized as the source of much of this RA. We explored possible trophoblast-derived sources of RA by examining the expression of RA synthesis enzymes in the developing mouse placenta, as well as addressed potential sites of RA action by examining the ontogeny of gene expression for other RA metabolizing and receptor genes. Furthermore, we investigated the effects of endogenous RA production on trophoblast differentiation. Placental tissues were examined by in situ hybridization and assayed for RARE-LacZ transgene activity to locate sites of RAR signaling. Trophoblast stem cell cultures were differentiated in the presence of ALDH1 inhibitors (DEAB and citral), and expression of labyrinth (Syna, Ctsq) and junctional zone (Tpbpa, Prl7b1, Prl7a2) marker genes were analyzed by qRT-PCR. We show Aldh1a3 is strongly expressed in a subset of ectoplacental cone cells and in glycogen trophoblast cells of the definitive murine placenta. Most trophoblast subtypes of the placenta express RA receptor combinations that would enable them to respond to RA signaling. Furthermore, expression of junctional zone markers decrease in differentiating trophoblast cultures when endogenous ALDH1 enzymes are inhibited. Aldh1a3 is a novel marker for glycogen trophoblast cells and their precursors and may play a role in the differentiation of junctional zone cell types via production of a local source of RA. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Alcohol flushing and positive ethanol patch test in patients with coronary spastic angina: possible role of aldehyde dehydrogenase 2 polymorphisms.

    Science.gov (United States)

    Mizuno, Yuji; Morita, Sumio; Harada, Eisaku; Shono, Makoto; Morikawa, Yoshinobu; Murohara, Toyoaki; Yasue, Hirofumi

    2013-01-01

    Coronary spasm plays an important role in the pathogenesis of coronary heart disease (CHD) and angina pectoris caused by coronary spasm or coronary spastic angina (CSA) is prevalent in Japan. However, the precise mechanisms underlying coronary spasm are unclear. Alcohol intolerance is prevalent among East Asians, and we previously reported that coronary spasm could be induced by alcohol intake in CSA patients. We herein examined whether CSA is associated with alcohol intolerance in Japanese subjects. The study subjects consisted of 80 CSA patients (57 men/ 23 women, mean age 62 ± 12) and 52 non-CSA patients (25 men/27 women, mean age 63 ± 10). The ethanol patch test (EPT) and questionnaire which evaluates flushing after ethanol intake, along with an examination of clinical features and laboratory chemistry data for CHD risk factors were done. Gender (male) and smoking were higher (p=0.007, and p=0.019, respectively) and plasma HDL cholesterol level was lower (p=0.035) in the CSA patients than in the non-CSA patients. Multivariable logistic regression analysis including age, EPT, smoking, and plasma HDL cholesterol level as independent variables revealed that positive EPT and smoking were significant predictors of CSA (p=0.011 and p=0.016, respectively). Positive EPT and alcohol flushing following alcohol intake, as well as smoking and plasma levels of HDL cholesterol, were significantly associated with CSA in Japanese patients. Therefore, alcohol ingestion as well as smoking is a significant risk factor for CSA in Japanese.

  7. A novel aldehyde dehydrogenase-3 activator (Alda-89) protects submandibular gland function from irradiation without accelerating tumor growth.

    Science.gov (United States)

    Xiao, Nan; Cao, Hongbin; Chen, Che-Hong; Kong, Christina S; Ali, Rehan; Chan, Cato; Sirjani, Davud; Graves, Edward; Koong, Albert; Giaccia, Amato; Mochly-Rosen, Daria; Le, Quynh-Thu

    2013-08-15

    To determine the effect of Alda-89 (an ALDH3 activitor) on (i) the function of irradiated (radiotherapy) submandibular gland (SMG) in mice, (ii) its toxicity profile, and (iii) its effect on the growth of head and neck cancer (HNC) in vitro and in vivo. Adult mice were infused with Alda-89 or vehicle before, during, and after radiotherapy. Saliva secretion was monitored weekly. Hematology, metabolic profile, and postmortem evaluation for toxicity were examined at the time of sacrifice. Alda-89 or vehicle was applied to HNC cell lines in vitro, and severe combined immunodeficient (SCID) mice transplanted with HNC in vivo with or without radiation; HNC growth was monitored. The ALDH3A1 and ALDH3A2 protein expression was evaluated in 89 patients with HNC and correlated to freedom from relapse (FFR) and overall survival (OS). Alda-89 infusion significantly resulted in more whole saliva production and a higher percentage of preserved acini after radiotherapy compared with vehicle control. There was no difference in the complete blood count, metabolic profile, and major organ morphology between the Alda-89 and vehicle groups. Compared with vehicle control, Alda-89 treatment neither accelerated HNC cell proliferation in vitro, nor did it affect tumor growth in vivo with or without radiotherapy. Higher expression of ALDH3A1 or ALDH3A2 was not significantly associated with worse FFR or OS in either human papillomavirus (HPV)-positive or HPV-negative group. Alda-89 preserves salivary function after radiotherapy without affecting HNC growth or causing measurable toxicity in mice. It is a promising candidate to mitigate radiotherapy-related xerostomia. ©2013 AACR.

  8. Methyltrioxorhenium as catalyst of a novel aldehyde olefination

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, W.A. (Technische Univ. Muenchen, Garching (Germany). Anorganisch-Chemisches Inst.); Wang Mei (Academia Sinica, Dalian Inst. of Chemical Physics (China))

    1991-12-01

    From aldehydes or cyclic ketones, diazoalkanes, and teritiary phosphanes, olefins may be prepared with MTO as catalyst. In particular, diazoacetates and -malonates (R{sup 2}, R{sup 3} = H, CO{sub 2}Et, or 2 x CO{sub 2}Me) can be transformed into olefins with aliphatic and aromatic aldehydes (R{sup 1} = iPr, trans-PhCH=CH, Ph, 4-NO{sub 2}C{sub 6}H{sub 4}, etc.). Readily accessible starting materials, easy handling, mild reaction conditions, and good yields characterize the new synthesis method. (R' = Ph, 3-C{sub 6}H{sub 4}SO{sub 3}Na, nBu.) (orig.).

  9. Copepod reproduction is unaffected by diatom aldehydes or lipid composition

    DEFF Research Database (Denmark)

    Dutz, Jörg; Koski, Marja; Jonasdottir, Sigrun

    2008-01-01

    ). Egg hatching rates decreased after 4 d in all diatom treatments, irrespective of the egg production rate and without any relationship to diatom aldehyde production. Similarly, no evidence was found that diatoms are per se nutritionally inferior to nondiatom food. The lack of a distinct mechanism......We investigated whether reduced reproductive success of copepods fed with diatoms was related to nutritional imbalances with regard to essential lipids or to the production of inhibitory aldehydes. In 10-d laboratory experiments, feeding, egg production, egg hatching success, and fecal pellet...... at high rates, they yielded a variable egg production response in copepods, ranging from high egg production in four species (two strains of Thalassiosira rotula, Chaetoceros affinis, and Thalassiosira weissflogii) to low egg production in two species (Leptocylindricus danicus and Skeletonema costatum...

  10. Methanol/Oxygen Enzymatic Biofuel Cell Using Laccase and NAD+-Dependent Dehydrogenase Cascades as Biocatalysts on Carbon Nanodots Electrodes.

    Science.gov (United States)

    Wu, Guozhi; Gao, Yue; Zhao, Dan; Ling, Pinghua; Gao, Feng

    2017-11-22

    The efficient immobilization of enzymes on favorable supporting materials to design enzyme electrodes endowed with specific catalysis performances such as deep oxidation of biofuels, and direct electron transfer (DET)-type bioelectrocatalysis is highly desired for fabricating enzymatic biofuel cells (BFCs). In this study, carbon nanodots (CNDs) have been used as the immobilizing matrixes and electron relays of enzymes to construct (NAD + )-dependent dehydrogenase cascades-based bioanode for the deep oxidation of methanol and DET-type laccase-based biocathode for oxygen reduction to water. At the bioanode, multiplex enzymes including alcohol dehydrogenase, aldehyde dehydrogenase, and formate dehydrogenase are coimmobilized on CNDs electrode which is previously coated with in situ polymerized methylene blue as the electrocatalyst for oxidizing NADH to NAD + . At the biocathode, fungal laccase is directly cast on CNDs and facilitated DET reaction is allowed. As a result, a novel membrane-less methanol/O 2 BFC has been assembled and displays a high open-circuit voltage of 0.71(±0.02) V and a maximum power density of 68.7 (±0.4) μW cm -2 . These investigated features imply that CNDs may act as new conductive architectures to elaborate enzyme electrodes for further bioelectrochemical applications.

  11. Substrate specificity of an aflatoxin-metabolizing aldehyde reductase.

    OpenAIRE

    Ellis, E M; Hayes, J D

    1995-01-01

    The enzyme from rat liver that reduces aflatoxin B1-dialdehyde exhibits a unique catalytic specificity distinct from that of other aldo-keto reductases. This enzyme, designated AFAR, displays high activity towards dicarbonyl-containing compounds with ketone groups on adjacent carbon atoms; 9,10-phenanthrenequinone, acenaphthenequinone and camphorquinone were found to be good substrates. Although AFAR can also reduce aromatic and aliphatic aldehydes such as succinic semialdehyde, it is inactiv...

  12. Aqueous Barbier Allylation of Aldehydes Mediated by Tin

    OpenAIRE

    Ivani Malvestiti; Lothar W. Bieber; Marcelo Navarro; Fernando Hallwass; Lívia N. Cavalcanti; Maria Ester S. B. Barros; Dimas J. P. Lima; Ricardo L. Guimarães

    2007-01-01

    The aqueous tin-mediated Barbier reaction affords good to excellent yields and moderate syn diastereoselectivity under basic and acidic conditions. The high yields and stereoselectivity observed in the case of o-substituted aldehydes suggest a cyclic organotin intermediate or transition state in K2HPO4 solution. A practical and efficient aqueous tin allylation of methoxy- and hydroxybenzaldehydes can be carried out in HCl solution in 15 minutes to afford the corresponding homoallylic alcohols...

  13. Gastric cytoprotective activity of ilicic aldehyde: structure-activity relationships.

    Science.gov (United States)

    Donadel, Osvaldo J; Guerreiro, Eduardo; María, Alejandra O; Wendel, Graciela; Enriz, Ricardo D; Giordano, Oscar S; Tonn, Carlos E

    2005-08-01

    A series of sesquiterpene compounds possessing both eudesmane and eremophilane skeletons were tested as gastric cytoprotective agents on male Wistar rats. The presence of an alpha,beta-unsaturated aldehyde on the C-7 side chain together with a hydroxyl group at C-4 is the requirement for the observed antiulcerogenic activity. In an attempt to establish new molecular structural requirements for this gastric cytoprotective activity, a structure-activity study was performed.

  14. In vitro assessment of human airway toxicity from major aldehydes in automotive emissions

    Energy Technology Data Exchange (ETDEWEB)

    Grafstroem, R.C. [Karolinska Inst., Stockholm (Sweden). Inst. of Environmental Medicine

    1997-09-01

    Automotive exhausts can significantly contribute to the levels of reactive aldehydes, including formaldehyde, acetaldehyde and acrolein, in urban air. The use of alcohols as an alternative fuel for gasoline or diesel may further increase these emissions. Since it is unclear if aldehyde inhalation may induce pathological states, including cancer, in human airways, the toxic properties of the above-mentioned aldehydes were studied in cultured target cell types. Each aldehyde modified vital cellular functions in a dose-dependent manner, and invariably inhibited growth and induced abnormal terminal differentiation. Decreases of cellular thiols and increases of intracellular Ca{sup 2+} were observed, and moreover, variable types and amounts of short-lived or persistent genetic damage were induced. The concentrations required for specified levels of a particular type of injury varied up to 10000-fold among the aldehydes. Overall, distinctive patterns of cytopathological activity were observed, which differed both qualitatively and quantitatively among the aldehydes. Finally, aldehydes inhibited DNA repair processes and increased cytotoxicity and mutagenesis in synergy with other known toxicants, indicating that aldehydes may also enhance damage by other constituents in automotive exhausts. In summary, the aldehydes, notably {sup m}u{sup M}-mM formaldehyde, caused pathological effects and induced mechanisms that relate to acute toxicity and cancer development in airway epithelial cells. Since `no-effect` levels may not exist for carcinogenic agents, the overall results support a need for elimination of aldehydes in automotive exhausts. 41 refs

  15. Anisaldehyde production and aryl-alcohol oxidase and dehydrogenase activities in ligninolytic fungi of the genus Pleurotus.

    Science.gov (United States)

    Gutiérrez, A; Caramelo, L; Prieto, A; Martínez, M J; Martínez, A T

    1994-01-01

    A variety of simple aromatic compounds were identified in liquid cultures of the basidiomycetes Pleurotus cornucopiae, P. eryngii, P. floridanus, P. pulmonarius, P. ostreatus, and P. sajor-caju by using gas chromatography-mass spectrometry. Such compounds were detected in fungal cultures on lignin- and straw-containing media, but it was found that they were also produced in the absence of aromatic precursors. Anisylic and hydroxybenzylic compounds (such as alcohols, aldehydes, and acids) were identified, p-anisaldehyde being the most characteristic extracellular metabolite synthesized by these ligninolytic fungi. Small amounts of 3-chloro-p-anisaldehyde were also detected in several species. It is postulated that the balance between the more-or-less-oxidized aromatic compounds can be explained in terms of the activity of fungal enzymes, including aryl-alcohol oxidase and dehydrogenase. The former enzyme shows high affinity for p-anisyl alcohol, which is oxidized to p-anisaldehyde with production of H2O2. The aryl-alcohol dehydrogenase was detected only in the mycelium, where it reduces aromatic aldehydes in the presence of NADPH. Both enzymes could be involved in the redox cycling of these aromatic compounds, providing H2O2 to ligninolytic peroxidases. PMID:8031078

  16. Toxicity and detoxification of lipid-derived aldehydes in cultured retinal pigmented epithelial cells

    International Nuclear Information System (INIS)

    Choudhary, S.; Xiao, T.; Srivastava, S.; Zhang, W.; Chan, L.L.; Vergara, L.A.; Van Kuijk, F.J.G.M.; Ansari, N.H.

    2005-01-01

    Age-related macular degeneration (ARMD) is the leading cause of blindness in the developed world and yet its pathogenesis remains poorly understood. Retina has high levels of polyunsaturated fatty acids (PUFAs) and functions under conditions of oxidative stress. To investigate whether peroxidative products of PUFAs induce apoptosis in retinal pigmented epithelial (RPE) cells and possibly contribute to ARMD, human retinal pigmented epithelial cells (ARPE-19) were exposed to micromolar concentrations of H 2 O 2 , 4-hydroxynonenal (HNE) and 4-hydroxyhexenal (HHE). A concentration- and time-dependent increase in H 2 O 2 -, HNE-, and HHE-induced apoptosis was observed when monitored by quantifying DNA fragmentation as determined by ELISA, flow cytometry, and Hoechst staining. The broad-spectrum inhibitor of apoptosis Z-VAD inhibited apoptosis. Treatment of RPE cells with a thionein peptide prior to exposure to H 2 O 2 or HNE reduced the formation of protein-HNE adducts as well as alteration in mitochondrial membrane potential and apoptosis. Using 3 H-HNE, various metabolic pathways to detoxify HNE by ARPE-19 cells were studied. The metabolites were separated by HPLC and characterized by ElectroSpray Ionization-Mass Spectrometry (ESI-MS) and gas chromatography-MS. Three main metabolic routes of HNE detoxification were detected: (1) conjugation with glutathione (GSH) to form GS-HNE, catalyzed by glutathione-S-transferase (GST) (2) reduction of GS-HNE catalyzed by aldose reductase, and (3) oxidation of HNE catalyzed by aldehyde dehydrogenase (ALDH). Preventing HNE formation by a combined strategy of antioxidants, scavenging HNE by thionein peptide, and inhibiting apoptosis by caspase inhibitors may offer a potential therapy to limit retinal degeneration in ARMD

  17. Identification and functional evaluation of the reductases and dehydrogenases from Saccharomyces cerevisiae involved in vanillin resistance.

    Science.gov (United States)

    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

  18. Highly stable and reusable immobilized formate dehydrogenases: Promising biocatalysts for in situ regeneration of NADH

    Directory of Open Access Journals (Sweden)

    Barış Binay

    2016-02-01

    Full Text Available This study aimed to prepare robust immobilized formate dehydrogenase (FDH preparations which can be used as effective biocatalysts along with functional oxidoreductases, in which in situ regeneration of NADH is required. For this purpose, Candida methylica FDH was covalently immobilized onto Immobead 150 support (FDHI150, Immobead 150 support modified with ethylenediamine and then activated with glutaraldehyde (FDHIGLU, and Immobead 150 support functionalized with aldehyde groups (FDHIALD. The highest immobilization yield and activity yield were obtained as 90% and 132%, respectively when Immobead 150 functionalized with aldehyde groups was used as support. The half-life times (t1/2 of free FDH, FDHI150, FDHIGLU and FDHIALD were calculated as 10.6, 28.9, 22.4 and 38.5 h, respectively at 35 °C. FDHI150, FDHIGLU and FDHIALD retained 69, 38 and 51% of their initial activities, respectively after 10 reuses. The results show that the FDHI150, FDHIGLU and FDHIALD offer feasible potentials for in situ regeneration of NADH.

  19. Branched chain aldehydes: production and breakdown pathways and relevance for flavour in foods

    OpenAIRE

    Smit, B.A.; Engels, W.J.M.; Smit, G.

    2009-01-01

    Branched aldehydes, such as 2-methyl propanal and 2- and 3-methyl butanal, are important flavour compounds in many food products, both fermented and non-fermented (heat-treated) products. The production and degradation of these aldehydes from amino acids is described and reviewed extensively in literature. This paper reviews aspects influencing the formation of these aldehydes at the level of metabolic conversions, microbial and food composition. Special emphasis was on 3-methyl butanal and i...

  20. On the nature of the olefination reaction involving ditungsten hexaalkoxides and aldehydes or ketones

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, M.H.; Huffman, J.C.; Lucas, E.A.; Sousa, A.; Streib, W.E. [Indiana Univ., Bloomington, IN (United States)

    1992-03-25

    Reductive coupling of aldehydes and ketones to olefins under the action of ditungsten hexaalkoxides was investigated. In these reactions, reductive cleavage of the aldehyde or ketone carbonyl is followed by formation of the olefinic C-C bond and breaking of the carbonyl C-O bond of the second aldehyde or ketone. Observations concerning the initial C-O bond cleavage and subsequent C-C bond formation are presented. 10 refs., 4 figs.

  1. 21 CFR 862.1500 - Malic dehydrogenase test system.

    Science.gov (United States)

    2010-04-01

    ... Systems § 862.1500 Malic dehydrogenase test system. (a) Identification. A malic dehydrogenase test system is a device that is intended to measure the activity of the enzyme malic dehydrogenase in serum and... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Malic dehydrogenase test system. 862.1500 Section...

  2. A role for glucose-6-phosphate dehydrogenase

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-19

    -phosphate dehydrogenase activity in male rats. Twelve (12) male rats were divided into two groups of six (6) rats each. Group 1 rats were control rats which received normal saline while group 2 rats were treated with.

  3. Genetics Home Reference: dihydrolipoamide dehydrogenase deficiency

    Science.gov (United States)

    ... Lacaille F, de Keyzer Y, Di Martino V, de Lonlay P. Dihydrolipoamide dehydrogenase deficiency: a still overlooked cause of recurrent acute liver failure and Reye-like syndrome. Mol Genet Metab. 2013 May;109(1):28- ...

  4. Histochemical localization of cytokinin oxidase/dehydrogenase ...

    African Journals Online (AJOL)

    Jane

    2011-08-15

    dehydrogenase, Withania somnifera, CKX localization. INTRODUCTION. Cytokinin (Ck) is a plant hormone that plays a crucial role in many fundamental processes of plant development throughout the life cycle. These include ...

  5. Hydrogenations without Hydrogen: Titania Photocatalyzed Reductions of Maleimides and Aldehydes

    Directory of Open Access Journals (Sweden)

    David W. Manley

    2014-09-01

    Full Text Available A mild procedure for the reduction of electron-deficient alkenes and carbonyl compounds is described. UVA irradiations of substituted maleimides with dispersions of titania (Aeroxide P25 in methanol/acetonitrile (1:9 solvent under dry anoxic conditions led to hydrogenation and production of the corresponding succinimides. Aromatic and heteroaromatic aldehydes were reduced to primary alcohols in similar titania photocatalyzed reactions. A mechanism is proposed which involves two proton-coupled electron transfers to the substrates at the titania surface.

  6. Monolayer structures of alkyl aldehydes: Odd-membered homologues

    International Nuclear Information System (INIS)

    Phillips, T.K.; Clarke, S.M.; Bhinde, T.; Castro, M.A.; Millan, C.; Medina, S.

    2011-01-01

    Crystalline monolayers of three aldehydes with an odd number of carbon atoms in the alkyl chain (C 7 , C 9 and C 11 ) at low coverages are observed by a combination of X-ray and neutron diffraction. Analysis of the diffraction data is discussed and possible monolayer crystal structures are proposed; although unique structures could not be ascertained for all molecules. We conclude that the structures are flat on the surface, with the molecules lying in the plane of the layer. The C 11 homologue is determined to have a plane group of either p2, pgb or pgg, and for the C 7 homologue the p2 plane group is preferred.

  7. Isocitrate dehydrogenase mutations in gliomas

    Science.gov (United States)

    Waitkus, Matthew S.; Diplas, Bill H.; Yan, Hai

    2016-01-01

    Over the last decade, extraordinary progress has been made in elucidating the underlying genetic causes of gliomas. In 2008, our understanding of glioma genetics was revolutionized when mutations in isocitrate dehydrogenase 1 and 2 (IDH1/2) were identified in the vast majority of progressive gliomas and secondary glioblastomas (GBMs). IDH enzymes normally catalyze the decarboxylation of isocitrate to generate α-ketoglutarate (αKG), but recurrent mutations at Arg132 of IDH1 and Arg172 of IDH2 confer a neomorphic enzyme activity that catalyzes reduction of αKG into the putative oncometabolite D-2-hydroxyglutate (D2HG). D2HG inhibits αKG-dependent dioxygenases and is thought to create a cellular state permissive to malignant transformation by altering cellular epigenetics and blocking normal differentiation processes. Herein, we discuss the relevant literature on mechanistic studies of IDH1/2 mutations in gliomas, and we review the potential impact of IDH1/2 mutations on molecular classification and glioma therapy. PMID:26188014

  8. [Pollution Characteristics of Aldehydes and Ketones Compounds in the Exhaust of Beijing Typical Restaurants].

    Science.gov (United States)

    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.

  9. Regulation of glutamate dehydrogenase in Bacillus subtilis.

    OpenAIRE

    Kane, J F; Wakim, J; Fischer, R S

    1981-01-01

    The activity of the nicotinamide adenine dinucleotide-dependent glutamate dehydrogenase in Bacillus subtilis was influenced by the carbon source, but not the nitrogen source, in the growth medium. The highest specific activity for this enzyme was found when B. subtilis was grown in a minimal or rich medium that contained glutamate as the carbon source. It is proposed that glutamate dehydrogenase serves a catabolic function in the metabolism of glutamate, is induced by glutamate, and is subjec...

  10. Regulation of glutamate dehydrogenase in Bacillus subtilis.

    Science.gov (United States)

    Kane, J F; Wakim, J; Fischer, R S

    1981-01-01

    The activity of the nicotinamide adenine dinucleotide-dependent glutamate dehydrogenase in Bacillus subtilis was influenced by the carbon source, but not the nitrogen source, in the growth medium. The highest specific activity for this enzyme was found when B. subtilis was grown in a minimal or rich medium that contained glutamate as the carbon source. It is proposed that glutamate dehydrogenase serves a catabolic function in the metabolism of glutamate, is induced by glutamate, and is subject to catabolite repression. PMID:6118356

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

    Directory of Open Access Journals (Sweden)

    Yang Dong-Dong

    2012-06-01

    Full Text Available Abstract 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.

  12. Sugar and Aldehyde Content in Flavored Electronic Cigarette Liquids.

    Science.gov (United States)

    Fagan, Pebbles; Pokhrel, Pallav; Herzog, Thaddeus A; Moolchan, Eric T; Cassel, Kevin D; Franke, Adrian A; Li, Xingnan; Pagano, Ian; Trinidad, Dennis R; Sakuma, Kari-Lyn K; Sterling, Kymberle; Jorgensen, Dorothy; Lynch, Tania; Kawamoto, Crissy; Guy, Mignonne C; Lagua, Ian; Hanes, Sarah; Alexander, Linda A; Clanton, Mark S; Graham-Tutt, Camonia; Eissenberg, Thomas

    2017-11-22

    Sugars are major constituents and additives in traditional tobacco products, but little is known about their content or related toxins (formaldehyde, acetaldehyde, and acrolein) in electronic cigarette (e-cigarette) liquids. This study quantified levels of sugars and aldehydes in e-cigarette liquids across brands, flavors, and nicotine concentrations (n = 66). Unheated e-cigarette liquids were analyzed using liquid chromatography mass spectrometry and enzymatic test kits. Generalized linear models, Fisher's exact test, and Pearson's correlation coefficient assessed sugar, aldehyde, and nicotine concentration associations. Glucose, fructose and sucrose levels exceeded the limits of quantification in 22%, 53% and 53% of the samples. Sucrose levels were significantly higher than glucose [χ2(1) = 85.9, p regulation of specific flavor constituents in tobacco products as a strategy to protect young people from using e-cigarettes, while balancing FDA's interest in how these emerging products could potentially benefit adult smokers who are seeking to safely quit cigarette smoking. The data can also be used to educate consumers about ingredients in products that may contain nicotine and inform future FDA regulatory policies related to product standards and accurate and comprehensible labeling of e-cigarette liquids. © The Author 2017. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Aqueous Barbier allylation of aldehydes mediated by tin.

    Science.gov (United States)

    Guimarães, Ricardo L; Lima, Dimas J P; Barros, Maria Ester S B; Cavalcanti, Lívia N; Hallwass, Fernando; Navarro, Marcelo; Bieber, Lothar W; Malvestiti, Ivani

    2007-08-29

    The aqueous tin-mediated Barbier reaction affords good to excellent yields and moderate syn diastereoselectivity under basic and acidic conditions. The high yields and stereoselectivity observed in the case of o-substituted aldehydes suggest a cyclic organotin intermediate or transition state in K2HPO4 solution. A practical and efficient aqueous tin allylation of methoxy- and hydroxybenzaldehydes can be carried out in HCl solution in 15 minutes to afford the corresponding homoallylic alcohols in high yields. Aliphatic aldehydes give moderate to excellent yields with reaction times ranging from 30 to 60 minutes. Under these conditions, crotylation gives exclusively the gamma-product and the syn isomer is formed preferentially. For 2-methoxybenzaldehyde, an equilibration of the isomers to a syn/anti ratio of 1:1 can be observed after several hours. Control experiments with radical sources or scavengers give no support for radical intermediates. NMR studies suggest a mechanism involving an organotin intermediate. The major organotin species formed depends on the reaction medium and the reaction time. The use of acidic solution reduces the reaction times, due to the acceleration of the formation of the allyltin(IV) species.

  14. Aqueous Barbier Allylation of Aldehydes Mediated by Tin

    Directory of Open Access Journals (Sweden)

    Ivani Malvestiti

    2007-08-01

    Full Text Available The aqueous tin-mediated Barbier reaction affords good to excellent yields and moderate syn diastereoselectivity under basic and acidic conditions. The high yields and stereoselectivity observed in the case of o-substituted aldehydes suggest a cyclic organotin intermediate or transition state in K2HPO4 solution. A practical and efficient aqueous tin allylation of methoxy- and hydroxybenzaldehydes can be carried out in HCl solution in 15 minutes to afford the corresponding homoallylic alcohols in high yields. Aliphatic aldehydes give moderate to excellent yields with reaction times ranging from 30 to 60 minutes. Under these conditions, crotylation gives exclusively the γ-product and the syn isomer is formed preferentially. For 2-methoxybenzaldehyde, an equilibration of the isomers to a syn/anti ratio of 1:1 can be observed after several hours. Control experiments with radical sources or scavengers give no support for radical intermediates. NMR studies suggest a mechanism involving an organotin intermediate. The major organotin species formed depends on the reaction medium and the reaction time. The use of acidic solution reduces the reaction times, due to the acceleration of the formation of the allyltin(IV species.

  15. The Complete Molecular Geometry of Salicyl Aldehyde from Rotational Spectroscopy

    Science.gov (United States)

    Dorosh, O.; Bialkowska-Jaworska, E.; Kisiel, Z.; Pszczolkowski, L.; Kanska, M.; Krygowski, T. M.; Maeder, H.

    2013-06-01

    Salicyl aldehyde is a well known planar molecule containing an internal hydrogen bond. In preparing the publication of our previous report of the study of its rotational spectrum we have taken the opportunity to update the structure determination of this molecule to the complete r_e^{SE} geometry. The molecule contains 15 atoms and we have used supersonic expansion FTMW spectroscopy to obtain rotational constants for a total 26 different isotopic species, including all singly substitued species relative to the parent molecule. The ^{13}C and ^{18}O substitutions were measured in natural abundance, while deuterium substitutions were carried out synthetically. The r_e^{SE} determination requires the calculation of vibration-rotation changes in rotational constants from an ab initio anharmonic force field, which necessitates some compromises in the level of calculation for a molecule of the size of salicyl aldehyde. For this reason we studied the five lowest vibrationally excited states, by using the combination of room-temperature mm-wave spectroscopy and waveguide Fourier transform cm-wave spectroscopy. The experimental excited state rotational constants were then used to calibrate the anharmonic force field calculation. The resulting r_e^{SE} geometry is compared with other types of geometry determination possible from this data, with emphasis on the effect of the near zero principal coordinate of the important C_2 atom. Z.Kisiel et al., 61^{st} OSU Symposium on Molecular Spectroscopy, The Ohio State University, Ohio 2006, RI-12.

  16. Toxic Diatom Aldehydes Affect Defence Gene Networks in Sea Urchins.

    Science.gov (United States)

    Varrella, Stefano; Romano, Giovanna; Costantini, Susan; Ruocco, Nadia; Ianora, Adrianna; Bentley, Matt G; Costantini, Maria

    2016-01-01

    Marine organisms possess a series of cellular strategies to counteract the negative effects of toxic compounds, including the massive reorganization of gene expression networks. Here we report the modulated dose-dependent response of activated genes by diatom polyunsaturated aldehydes (PUAs) in the sea urchin Paracentrotus lividus. PUAs are secondary metabolites deriving from the oxidation of fatty acids, inducing deleterious effects on the reproduction and development of planktonic and benthic organisms that feed on these unicellular algae and with anti-cancer activity. Our previous results showed that PUAs target several genes, implicated in different functional processes in this sea urchin. Using interactomic Ingenuity Pathway Analysis we now show that the genes targeted by PUAs are correlated with four HUB genes, NF-κB, p53, δ-2-catenin and HIF1A, which have not been previously reported for P. lividus. We propose a working model describing hypothetical pathways potentially involved in toxic aldehyde stress response in sea urchins. This represents the first report on gene networks affected by PUAs, opening new perspectives in understanding the cellular mechanisms underlying the response of benthic organisms to diatom exposure.

  17. Toxic Diatom Aldehydes Affect Defence Gene Networks in Sea Urchins.

    Directory of Open Access Journals (Sweden)

    Stefano Varrella

    Full Text Available Marine organisms possess a series of cellular strategies to counteract the negative effects of toxic compounds, including the massive reorganization of gene expression networks. Here we report the modulated dose-dependent response of activated genes by diatom polyunsaturated aldehydes (PUAs in the sea urchin Paracentrotus lividus. PUAs are secondary metabolites deriving from the oxidation of fatty acids, inducing deleterious effects on the reproduction and development of planktonic and benthic organisms that feed on these unicellular algae and with anti-cancer activity. Our previous results showed that PUAs target several genes, implicated in different functional processes in this sea urchin. Using interactomic Ingenuity Pathway Analysis we now show that the genes targeted by PUAs are correlated with four HUB genes, NF-κB, p53, δ-2-catenin and HIF1A, which have not been previously reported for P. lividus. We propose a working model describing hypothetical pathways potentially involved in toxic aldehyde stress response in sea urchins. This represents the first report on gene networks affected by PUAs, opening new perspectives in understanding the cellular mechanisms underlying the response of benthic organisms to diatom exposure.

  18. Radon and aldehyde concentrations in the indoor environment. Final report

    International Nuclear Information System (INIS)

    Moschandreas, D.J.; Rector, H.E.

    1981-04-01

    Findings regarding indoor air contaminants in the energy-efficient residence (EER) in Mt. Airy, Maryland are reported. The objectives of the study were to collect and analyze relevant air quality samples (specifically radon and aldehydes), characterize the indoor air quality with respect to radon and aldehydes, and develop relationships between air infiltration rates and contaminant levels. One-fifth of the measured formaldehyde concentrations were in the range that may cause health concerns. Although indoor temperature and relative humidity affect indoor HCHO concentration, the elevated formaldehyde concentrations were measured under very low air infiltration rates. The data show that ventilation of the indoor air space is somewhat effective in reducing high HCHO concentrations. The operation of the heat exchanger led to an increase of the air infiltration rate which in turn resulted in substantial reduction of formaldehyde concentrations. A considerable number of the collected samples of indoor air displayed radon concentrations at levels higher than 1.0 to 4.0 nCim -3 (assuming an equilibrium factor of 0.5, these radon levels would correspond to working levels above the health guidelines suggested by the US EPA for homes in Florida built on land reclaimed from phosphate mining). As in the case of indoor formaldehyde concentrations, elevated indoor concentrations are substantially reduced when the infiltration rate is increased. The data base shows that the use of the air to air heat exchanger leads to reduction of indoor radon concentration by increasing the residential ventilation rate

  19. Fluorescein Tri-Aldehyde Promotes the Selective Detection of Homocysteine.

    Science.gov (United States)

    Barve, Aabha; Lowry, Mark; Escobedo, Jorge O; Thainashmuthu, Josephrajan; Strongin, Robert M

    2016-03-01

    Elevated homocysteine levels are a well-known independent risk factor for cardiovascular disease. To date, relatively few selective fluorescent probes for homocysteine detection have been reported. The lack of sensing reagents and remaining challenges largely derive from issues of sensitivity and/or selectivity. For example, homocysteine is a structural homologue of the more abundant (ca, 20-25 fold) aminothiol cysteine, differing only by an additional methylene group side chain. Fluorescein tri-aldehyde, described herein, has been designed and synthesized as a sensitive and selective fluorophore for the detection of homocysteine in human plasma samples. It responds to analytes selectively via a photoinduced electron transfer (PET) inhibition process that is modulated by predictable analyte-dye product hybridization and ionization states. Mulliken population analysis of fluorescein tri-aldehyde and its reaction products reveals that the characteristic formation of multiple cationic of homocysteine-derived heterocycles leads to enhanced relative negative charge build up on the proximal phenolate oxygen of the fluorophore as a contributing factor to selective emission enhancement.

  20. Volatile aldehydes are promising broad-spectrum postharvest insecticides.

    Science.gov (United States)

    Hammond, D G; Rangel, S; Kubo, I

    2000-09-01

    A variety of naturally occurring aldehydes common in plants have been evaluated for their insecticidal activity and for phytotoxicity to postharvest fruits, vegetables, and grains. Twenty-nine compounds were initially screened for their activity against aphids on fava bean leaf disks. Application under reduced pressure (partial vacuum) for the first quarter of fumigation increased insecticidal activity severalfold. The 11 best aldehydes were assayed against aphids placed under the third leaf of whole heads of iceberg lettuce using the same two-tier reduced-pressure regime, which caused no additional detriment to the commodity over fumigation at atmospheric pressure. Phytotoxicity to naked and wrapped iceburg lettuce, green and red table grapes, lemon, grapefruit, orange, broccoli, avocado, cabbage, pinto bean, and rice at doses that killed 100% of aphids was recorded for three promising fumigants: propanal, (E)-2-pentenal, and 2-methyl-(E)-2-butenal. These three compounds have excellent potential as affordable postharvest insect control agents, killing 100% of the aphids with little or no detectable harm to a majority of the commodities tested. Preliminary assays indicate that similar doses are also effective against mealybugs, thrips, and whitefly.

  1. Aromatic aldehydes at the active site of aldehyde oxidoreductase from Desulfovibrio gigas: reactivity and molecular details of the enzyme-substrate and enzyme-product interaction.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2018-01-11

    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.

  3. A new cotton SDR family gene encodes a polypeptide possessing aldehyde reductase and 3-ketoacyl-CoA reductase activities.

    Science.gov (United States)

    Pang, Yu; Song, Wen-Qiang; Chen, Fang-Yuan; Qin, Yong-Mei

    2010-03-01

    To understand regulatory mechanisms of cotton fiber development, microarray analysis has been performed for upland cotton (Gossypium hirsutum). Based on this, a cDNA (GhKCR3) encoding a polypeptide belonging to short-chain alcohol dehydrogenase/reductase family was isolated and cloned. It contains an open reading frame of 987 bp encoding a polypeptide of 328 amino acid residues. Following its overexpression in bacterial cells, the purified recombinant protein specifically uses NADPH to reduce a variety of short-chain aldehydes. A fragment between Gly180 and Gly191 was found to be essential for its catalytic activity. Though the GhKCR3 gene shares low sequence similarities to the ortholog of Saccharomyces cerevisiae YBR159w that encodes 3-ketoacyl-CoA reductase (KCR) catalyzing the second step of fatty acid elongation, it was surprisingly able to complement the yeast ybr159wDelta mutant. Gas chromatography-mass spectrometry analysis showed that very long-chain fatty acids, especially C26:0, were produced in the ybr159wDelta mutant cells expressing GhKCR3. Applying palmitoyl-CoA and malonyl-CoA as substrates, GhKCR3 showed KCR activity in vitro. Quantitative real time-PCR analysis indicated GhKCR3 transcripts accumulated in rapidly elongating fibers, roots, and stems. Our results suggest that GhKCR3 is probably a novel KCR contributing to very long-chain fatty acid biosynthesis in plants.

  4. Threshold responses in cinnamic-aldehyde-sensitive subjects: results and methodological aspects

    DEFF Research Database (Denmark)

    Johansen, J D; Andersen, Klaus Ejner; Rastogi, S C

    1996-01-01

    Cinnamic aldehyde is an important fragrance material and contact allergen. The present study was performed to provide quantitative data on the eliciting capacity of cinnamic aldehyde, to be considered in assessment of clinical relevance and health hazard. The skin response to serial dilution patc...

  5. Effects of cooking method, cooking oil, and food type on aldehyde emissions in cooking oil fumes.

    Science.gov (United States)

    Peng, Chiung-Yu; Lan, Cheng-Hang; Lin, Pei-Chen; Kuo, Yi-Chun

    2017-02-15

    Cooking oil fumes (COFs) contain a mixture of chemicals. Of all chemicals, aldehydes draw a great attention since several of them are considered carcinogenic and formation of long-chain aldehydes is related to fatty acids in cooking oils. The objectives of this research were to compare aldehyde compositions and concentrations in COFs produced by different cooking oils, cooking methods, and food types and to suggest better cooking practices. This study compared aldehydes in COFs produced using four cooking oils (palm oil, rapeseed oil, sunflower oil, and soybean oil), three cooking methods (stir frying, pan frying, and deep frying), and two foods (potato and pork loin) in a typical kitchen. Results showed the highest total aldehyde emissions in cooking methods were produced by deep frying, followed by pan frying then by stir frying. Sunflower oil had the highest emissions of total aldehydes, regardless of cooking method and food type whereas rapeseed oil and palm oil had relatively lower emissions. This study suggests that using gentle cooking methods (e.g., stir frying) and using oils low in unsaturated fatty acids (e.g., palm oil or rapeseed oil) can reduce the production of aldehydes in COFs, especially long-chain aldehydes such as hexanal and t,t-2,4-DDE. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. L-proline-catalyzed enantioselective one-pot cross-Mannich reaction of aldehydes.

    Science.gov (United States)

    Hayashi, Yujiro; Urushima, Tatsuya; Tsuboi, Wataru; Shoji, Mitsuru

    2007-01-01

    This protocol describes a procedure for the synthesis of syn-beta-amino alpha-substituted aldehydes, versatile intermediates in synthetic organic chemistry, via asymmetric, direct, one-pot, three-component, cross-Mannich reaction of two different aldehydes. The reaction consists of two steps; one is the formation of imine by the reaction of aldehyde and p-anisidine in the presence of Pro, and the second step is the enantioselective addition reaction of enamine generated from the other aldehyde and Pro with the imine generated in the first step. As the aldehyde easily racemizes, gamma-amino alcohol was isolated and characterized after reduction. The yield and diastereo- and enantioselectivities are generally excellent. It will take approximately 26 h to complete the protocol: 0.5 h to set up the reaction, 20.5 h for the reaction and 5 h for the isolation and purification.

  7. Substrate specificity of an aflatoxin-metabolizing aldehyde reductase.

    Science.gov (United States)

    Ellis, E M; Hayes, J D

    1995-01-01

    The enzyme from rat liver that reduces aflatoxin B1-dialdehyde exhibits a unique catalytic specificity distinct from that of other aldo-keto reductases. This enzyme, designated AFAR, displays high activity towards dicarbonyl-containing compounds with ketone groups on adjacent carbon atoms; 9,10-phenanthrenequinone, acenaphthenequinone and camphorquinone were found to be good substrates. Although AFAR can also reduce aromatic and aliphatic aldehydes such as succinic semialdehyde, it is inactive with glucose, galactose and xylose. The enzyme also exhibits low activity towards alpha,beta-unsaturated carbonyl-containing compounds. Determination of the apparent Km reveals that AFAR has highest affinity for 9,10-phenanthrenequinone and succinic semialdehyde, and low affinity for glyoxal and DL-glyceraldehyde. PMID:8526867

  8. DNA-Templated Introduction of an Aldehyde Handle in Proteins

    DEFF Research Database (Denmark)

    Kodal, Anne Louise Bank; Rosen, Christian Bech; Mortensen, Michael Rosholm

    2016-01-01

    Many medical and biotechnological applications rely on labeling of proteins, but one key challenge is the production of homogeneous and site-specific conjugates. This can rarely be achieved by mere residue-specific random labeling, but requires genetic engineering. Using site-selective DNA......-templated reductive amination we create DNA-protein conjugates with control over labeling stoichiometry without genetic engineering. A guiding DNA strand with a metal-binding functionality facilitates site-selectivity by directing coupling of a second reactive DNA strand to the vicinity of a protein metal......-binding site. Here, we demonstrate DNA-templated reductive amination for His6-tagged proteins and native metal-binding proteins, including IgG1 antibodies. We also use a cleavable linker between the DNA and the protein to remove the DNA and introduce a single aldehyde to proteins. This functions as a handle...

  9. Pharmacological activities of cilantro's aliphatic aldehydes against Leishmania donovani.

    Science.gov (United States)

    Donega, Mateus A; Mello, Simone C; Moraes, Rita M; Jain, Surendra K; Tekwani, Babu L; Cantrell, Charles L

    2014-12-01

    Leishmaniasis is a chronic infectious disease caused by different Leishmania species. Global occurrences of this disease are primarily limited to tropical and subtropical regions. Treatments are available; however, patients complain of side effects. Different species of plants have been screened as a potential source of new drugs against leishmaniasis. In this study, we investigated the antileishmanial activity of cilantro (Coriandrum sativum) essential oil and its main components: (E)-2-undecenal, (E)-2-decenal, (E)-2-dodecenal, decanal, dodecanal, and tetradecanal. The essential oil of C. sativum leaves inhibits growth of Leishmani donovani promastigotes in culture with an IC50 of 26.58 ± 6.11 µg/mL. The aliphatic aldehydes (E)-2-decenal (7.85 ± 0.28 µg/mL), (E)-2-undecenal (2.81 ± 0.21 µg/mL), and (E)-2-dodecenal (4.35 ± 0.15 µg/mL), all isolated from C. sativum essential oil, are effective inhibitors of in vitro cultures of L. donovani promastigotes. Aldehydes (E)-2-decenal, (E)-2-undecenal, and (E)-2-dodecenal were also evaluated against axenic amastigotes and IC50 values were determined to be 2.47 ± 0.25 µg/mL, 1.25 ± 0.11 µg/mL, and 4.78 ± 1.12 µg/mL, respectively. (E)-2-Undecenal and (E)-2-dodecenal demonstrated IC50 values of 5.65 ± 0.19 µg/mL and 9.60 ± 0.89 µg/mL, respectively, against macrophage amastigotes. These cilantro compounds showed no cytotoxicity against THP-1 macrophages. Georg Thieme Verlag KG Stuttgart · New York.

  10. Glusoce-6-phosphate dehydrogenase- History and diagnosis

    Directory of Open Access Journals (Sweden)

    K Gautam

    2016-09-01

    Full Text Available Glucose-6-phosphate dehydrogenase deficiency is the most common enzymatic defect of red blood cells, which increases the vulnerability of erythrocytes to oxidative stress leading to hemolytic anemia. Since its identification more than 60 years ago, much has been done with respect to its clinical diagnosis, laboratory diagnosis and treatment. Association of G6PD is not just limited to anti malarial drugs, but a vast number of other diseases. In this article, we aimed to review the history of Glucose-6-phosphate dehydrogenase, the diagnostic methods available along with its association with other noncommunicable diseases. 

  11. Inducible xylitol dehydrogenases in enteric bacteria.

    OpenAIRE

    Doten, R C; Mortlock, R P

    1985-01-01

    Morganella morganii ATCC 25829, Providencia stuartii ATCC 25827, Serratia marcescens ATCC 13880, and Erwinia sp. strain 4D2P were found to induce a xylitol dehydrogenase when grown on a xylitol-containing medium. The xylitol dehydrogenases were partially purified from the four strains, and those from M. morganii ATCC 25829, P. stuartii ATCC 25827, and S. marcescens ATCC 13880 were all found to oxidize xylitol to D-xylulose. These three enzymes had KmS for xylitol of 7.1 to 16.4 mM and molecul...

  12. Genetics Home Reference: glucose-6-phosphate dehydrogenase deficiency

    Science.gov (United States)

    ... deficiency Encyclopedia: Glucose-6-phosphate dehydrogenase test Encyclopedia: Hemolytic anemia Encyclopedia: Newborn jaundice Health Topic: Anemia Health Topic: G6PD Deficiency Health Topic: Newborn Screening Genetic and Rare Diseases Information Center (1 link) Glucose-6-phosphate dehydrogenase ...

  13. Control of aldehyde emissions in the diesel engines with alcoholic fuels.

    Science.gov (United States)

    Krishna, M V S Murali; Varaprasad, C M; Reddy, C Venkata Ramana

    2006-01-01

    The major pollutants emitted from compression ignition (CI) engine with diesel as fuel are smoke and nitrogen oxides (NOx). When the diesel engine is run with alternate fuels, there is need to check alcohols (methanol or ethanol) and aldehydes also. Alcohols cannot be used directly in diesel engine and hence engine modification is essential as alcohols have low cetane number and high latent hear of vaporization. Hence, for use of alcohol in diesel engine, it needs hot combustion chamber, which is provided by low heat rejection (LHR) diesel engine with an air gap insulated piston with superni crown and air gap insulated liner with superni insert. In the present study, the pollution levels of aldehydes are reported with the use of methanol and ethanol as alternate fuels in LHR diesel engine with varying injection pressure, injection timings with different percentage of alcohol induction. The aldehydes (formaldehyde and acetaldehyde) in the exhaust were estimated by wet chemical technique with high performance liquid chromatograph (HPLC). Aldehyde emissions increased with an increase in alcohol induction. The LHR engine showed a decrease in aldehyde emissions when compared to conventional engine. However, the variation of injection pressure showed a marginal effect in reducing aldehydes, while advancing the injection timing reduced aldehyde emissions.

  14. Effect of selected aldehydes on the growth and fermentation of ethanologenic Escherichia coli.

    Science.gov (United States)

    Zaldivar, J; Martinez, A; Ingram, L O

    1999-10-05

    Bioethanol production from lignocellulosic raw-materials requires the hydrolysis of carbohydrate polymers into a fermentable syrup. During the hydrolysis of hemicellulose with dilute acid, a variety of toxic compounds are produced such as soluble aromatic aldehydes from lignin and furfural from pentose destruction. In this study, we have investigated the toxicity of representative aldehydes (furfural, 5-hydroxymethlyfurfural, 4-hydroxybenzaldehyde, syringaldehyde, and vanillin) as inhibitors of growth and ethanol production by ethanologenic derivatives of Escherichia coli B (strains KO11 and LY01). Aromatic aldehydes were at least twice as toxic as furfural or 5-hydroxymethylfurfural on a weight basis. The toxicities of all aldehydes (and ethanol) except furfural were additive when tested in binary combinations. In all cases, combinations with furfural were unexpectedly toxic. Although the potency of these aldehydes was directly related to hydrophobicity indicating a hydrophobic site of action, none caused sufficient membrane damage to allow the leakage of intracellular magnesium even when present at sixfold the concentrations required for growth inhibition. Of the aldehydes tested, only furfural strongly inhibited ethanol production in vitro. A comparison with published results for other microorganisms indicates that LY01 is equivalent or more resistant than other biocatalysts to the aldehydes examined in this study. Copyright 1999 John Wiley & Sons, Inc.

  15. Malaria Protection In Glucose-6-Phosphate Dehydrogenase ...

    African Journals Online (AJOL)

    The high frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency gene in malaria endemic regions is believed to be due to the enzyme deficiency advantage against fatal malaria. However, the mechanism of this protection is not well understood and therefore was investigated by comparing differences in ...

  16. Coenzyme and effector binding to glutamate dehydrogenase

    NARCIS (Netherlands)

    Zantema, Alt

    1979-01-01

    Glutamaat-dehydrogenase is een enzym dat de reactie katalyseert van 2-oxoglutaraat (substraat), NAD(P)H (co-enzym) en ammonia naar L-glutaminezuur en NAD(P)+. Het enzym is opgebouwd uit 6 identieke subeenheden. Dit proefschrift beschrijft de bestudering van twee aspecten van dit enzym, nl. 1. de

  17. Optimization of Adsorptive Immobilization of Alcohol Dehydrogenases

    NARCIS (Netherlands)

    Trivedi, Archana; Heinemann, Matthias; Spiess, Antje C.; Daussmann, Thomas; Büchs, Jochen

    2005-01-01

    In this work, a systematic examination of various parameters of adsorptive immobilization of alcohol dehydrogenases (ADHs) on solid support is performed and the impact of these parameters on immobilization efficiency is studied. Depending on the source of the enzymes, these parameters differently

  18. Aryl-aldehyde formation in fungal polyketides: discovery and characterization of a distinct biosynthetic mechanism.

    Science.gov (United States)

    Wang, Meng; Beissner, Mirko; Zhao, Huimin

    2014-02-20

    Aryl-aldehydes are a common feature in fungal polyketides, which are considered to be exclusively generated by the R domain of nonreducing polyketide synthases (NR-PKSs). However, by cloning and heterologous expression of both cryptic NR-PKS and nonribosomal peptide synthase (NRPS)-like genes from Aspergillus terreus in Saccharomyces cerevisiae, we identified a distinct mechanism for aryl-aldehyde formation in which a NRPS-like protein activates and reduces an aryl-acid produced by the accompanying NR-PKS to an aryl-aldehyde. Bioinformatics study indicates that such a mechanism may be widely used throughout the fungi kingdom. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Mechanism of catalytic action of oxide systems in reactions of aldehyde oxidation to carboxylic acids

    International Nuclear Information System (INIS)

    Andrushkevich, T.V.

    1997-01-01

    Mechanism of selective action of oxide catalysts (on the base of V 2 O 4 , MoO 3 ) of aldehyde oxidation to acids is considered, reaction acrolein oxidation to acrylic acid is taken as an example. Multistage mechanism of the process is established; it involves consequent transformation of coordination-bonded aldehyde into carbonyl-bonded aldehyde and symmetric carboxylate. Principles of active surface construction are formulated, they take into account the activity of stabilization center of concrete intermediate compound and bond energy of oxygen with surface. (author)

  20. Facile palladium-mediated conversion of ethanethiol esters to aldehydes and ketones

    International Nuclear Information System (INIS)

    Tokuyama, Hidetoshi; Yokoshima, Satoshi; Yamashita, Tohru; Shao-Cheng, Lin; Leping, Li; Fukuyama, Tohru

    1998-01-01

    Treatment of ethanethiol esters with triethylsilane and palladium on carbon at ambient temperature furnished aldehydes. In addition, a variety of ketones have been prepared by a palladium-catalyzed reaction of ethanethiol esters with organo zinc reagents. Various functional groups, including esters, ketones, aromatic halides and aldehydes, tolerate both transformation reactions. These novel reactions can also be applied to the synthesis of α-amino aldehyde and α-amino ketone derivatives using the corresponding L-α-amino thiol esters without causing racemization. (author)

  1. Sulfur-rich zinc chemistry: new tris(thioimidazolyl)hydroborate ligands and their zinc complex chemistry related to the structure and function of alcohol dehydrogenase.

    Science.gov (United States)

    Tesmer, M; Shu, M; Vahrenkamp, H

    2001-07-30

    The 1-substituted tris(2-thioimidazolyl)hydroborate ligands Tt(R) were prepared as the potassium salts from KBH(4) and the corresponding 1-R-2-thioimidazole for R = t-Bu and C(6)H(4)-p-CH(CH(3))(2) (Cum). Their reactions with zinc salts yielded the tetrahedral complexes Tt(R)Zn-X with X = F, Cl, ONO(2) and (Tt(t)()(-)(Bu))(2)Zn. With zinc perchlorate the labile perchlorate complexes Tt(R)Zn-OClO(3) were obtained. They served as starting materials for the incorporation of substrates which are relevant for the chemistry of horse liver alcohol dehydrogenase: Ethanol led to [Tt(t)()(-Bu)Zn.EtOH] ClO(4).EtOH, p-nitrophenol (NitOH) yielded Tt(Cum)Zn-ONit. Pyridine-2-carbaldehyde and salicylic aldehyde were incorporated as N(pyridine) and O(phenolate) coligands with possible additional O(aldehyde) coordination. Substituted pyridyl methanols (R-PyCH(2)OH) yielded the trinuclear complexes [(Tt(t)()(-Bu))(2)Zn(3)(R-PyCH(2)O)(2)] (ClO(4))(2) with bridging Tt and pyridylmethoxide ligands. Preliminary experiments on the functional modeling of alcohol dehydrogenase have shown that TtZn complexes promote both the dehydrogenation of 2-propanol and the hydrogenation of pentafluorobenzaldehyde.

  2. MOLECULAR MODELLING OF HUMAN ALDEHYDE OXIDASE AND IDENTIFICATION OF THE KEY INTERACTIONS IN THE ENZYME-SUBSTRATE COMPLEX

    Directory of Open Access Journals (Sweden)

    Siavoush Dastmalchi

    2005-05-01

    Full Text Available Aldehyde oxidase (EC 1.2.3.1, a cytosolic enzyme containing FAD, molybdenum and iron-sulphur cluster, is a member of non-cytochrome P-450 enzymes called molybdenum hydroxylases which is involved in the metabolism of a wide range of endogenous compounds and many drug substances. Drug metabolism is one of the important characteristics which influences many aspects of a therapeutic agent such as routes of administration, drug interaction and toxicity and therefore, characterisation of the key interactions between enzymes and substrates is very important from drug development point of view. The aim of this study was to generate a three-dimensional model of human aldehyde oxidase (AO in order to assist us to identify the mode of interaction between enzyme and a set of phethalazine/quinazoline derivatives. Both sequence-based (BLAST and inverse protein fold recognition methods (THREADER were used to identify the crystal structure of bovine xanthine dehydrogenase (pdb code of 1FO4 as the suitable template for comparative modelling of human AO. Model structure was generated by aligning and then threading the sequence of human AO onto the template structure, incorporating the associated cofactors, and molecular dynamics simulations and energy minimization using GROMACS program. Different criteria which were measured by the PROCHECK, QPACK, VERIFY-3D were indicative of a proper fold for the predicted structural model of human AO. For example, 97.9 percentages of phi and psi angles were in the favoured and most favoured regions in the ramachandran plot, and all residues in the model are assigned environmentally positive compatibility scores. Further evaluation on the model quality was performed by investigation of AO-mediated oxidation of a set of phthalazine/quinazoline derivatives to develop QSAR model capable of describing the extent of the oxidation. Substrates were aligned by docking onto the active site of the enzyme using GOLD technology and then

  3. Disruption of seven hypothetical aryl alcohol dehydrogenase genes from Saccharomyces cerevisiae and construction of a multiple knock-out strain.

    Science.gov (United States)

    Delneri, D; Gardner, D C; Bruschi, C V; Oliver, S G

    1999-11-01

    By in silicio analysis, we have discovered that there are seven open reading frames (ORFs) in Saccharomyces cerevisiae whose protein products show a high degree of amino acid sequence similarity to the aryl alcohol dehydrogenase (AAD) of the lignin-degrading fungus Phanerochaete chrysosporium. Yeast cultures grown to stationary phase display a significant aryl alcohol dehydrogenase activity by degrading aromatic aldehydes to the corresponding alcohols. To study the biochemical and the biological role of each of the AAD genes, a series of mutant strains carrying deletion of one or more of the AAD-coding sequences was constructed by PCR-mediated gene replacement, using the readily selectable marker kanMX. The correct targeting of the PCR-generated disruption cassette into the genomic locus was verified by analytical PCR and by pulse-field gel electrophoresis (PFGE) followed by Southern blot analysis. Double, triple and quadruple mutant strains were obtained by classical genetic methods, while the construction of the quintuple, sextuple and septuple mutants was achieved by using the marker URA3 from Kluyveromyces lactis, HIS3 from Schizosaccharomyces pombe and TRP1 from S. cerevisiae. None of the knock-out strains revealed any mutant phenotype when tested for the degradation of aromatic aldehydes using both spectrophotometry and high performance liquid chromatography (HPLC). Specific tests for changes in the ergosterol and phospholipids profiles did not reveal any mutant phenotype and mating and sporulation efficiencies were not affected in the septuple deletant. Compared to the wild-type strain, the septuple deletant showed an increased resistance to the anisaldehyde, but there is a possibility that the nutritional markers used for gene replacement are causing this effect. Copyright 1999 John Wiley & Sons, Ltd.

  4. Interspecies variation in the metabolism of zoniporide by aldehyde oxidase.

    Science.gov (United States)

    Dalvie, Deepak; Xiang, Cathie; Kang, Ping; Zhou, Sue

    2013-05-01

    1. Aldehyde oxidase (AO) is a cytosolic enzyme that contributes to the Phase I metabolism of xenobiotics in human and preclinical species. 2. Current studies explored in vitro metabolism of zoniporide in various animal species and humans using S9 fractions. The animal species included commonly used pharmacology and toxicology models and domestic animals such as the cat, cow or bull, pig and horse. 3. In addition, gender and strain differences in some species were also explored. 4. All animals except the dog and cat converted zoniporide to 2-oxozoniporide (M1). 5. Michael-Menten kinetic studies were conducted in species that turned over zoniporide to M1. 6. Marked differences in KM, Vmax and Clint were observed in the oxidation of zoniporide. 7. Although the KM and Vmax of zoniporide oxidation in male and female human S9 was similar, some gender difference was observed in animals especially, in Vmax. 8. The domestic animals also showed marked species differences in the AO activity and affinity toward zoniporide.

  5. Sodium borohydride removes aldehyde inhibitors for enhancing biohydrogen fermentation.

    Science.gov (United States)

    Lin, Richen; Cheng, Jun; Ding, Lingkan; Song, Wenlu; Zhou, Junhu; Cen, Kefa

    2015-12-01

    To enhance biohydrogen production from glucose and xylose in the presence of aldehyde inhibitors, reducing agent (i.e., sodium borohydride) was in situ added for effective detoxification. The detoxification efficiencies of furfural (96.7%) and 5-hydroxymethylfurfural (5-HMF, 91.7%) with 30mM NaBH4 were much higher than those of vanillin (77.3%) and syringaldehyde (69.3%). Biohydrogen fermentation was completely inhibited without detoxification, probably because of the consumption of nicotinamide adenine dinucleotide (NADH) by inhibitors reduction (R-CHO+2NADH→R-CH2OH+2NAD(+)). Addition of 30mM NaBH4 provided the reducing power necessary for inhibitors reduction (4R-CHO+NaBH4+2H2O→4R-CH2OH+NaBO2). The recovered reducing power in fermentation resulted in 99.3% recovery of the hydrogen yield and 64.6% recovery of peak production rate. Metabolite production and carbon conversion after detoxification significantly increased to 63.7mM and 81.9%, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Coniferyl Aldehyde Ameliorates Radiation Intestine Injury via Endothelial Cell Survival

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ye Ji; Jung, Myung Gu; Lee, Yoonjin; Lee, Haejune [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yunsil [Ewha Woman' s Univ., Seoul (Korea, Republic of); Ko, Younggyu [Korea Univ., Seoul (Korea, Republic of)

    2014-05-15

    Cancer treatments related gastrointestinal toxicity has also been recognized as a significant economic burden. Especially, extensive apoptosis of microvascular endothelial cell of the lamina propria is the primary lesion initiating intestinal radiation damage after abdominal radiation therapy. Coniferyl aldehyde (CA) is phenolic compounds isolated from cork stoppers, and one of the major pyrolysis products of lignin. Shi H. was support for the empirical use of CA as a medicinal food for cardiovascular diseases. CA has positive effect in broad way but there is no consequence in radiation induced intestine damage. Here, we investigate effect of CA on small intestine after abdominal IR to mice in this study. In this study, CA increased the survival rate in C3H mice against 13.5 Gy abdominal IR. We found CA protects small intestine via preventing endothelial cell apoptosis and enhancing their angiogenic activity. CA also showed protective effect on crypt cell survival. Endothelial cell survival may affect crypt cell protection against IR. From this data, we concluded that CA is effective for protection against abdominal radiation injury. CA could ameliorate side-effect of radiation therapy.

  7. Kinetics, mechanism and thermodynamics of bisulfite-aldehyde adduct formation

    Energy Technology Data Exchange (ETDEWEB)

    Olson, T.M.; Boyce, S.D.; Hoffmann, M.R.

    1986-04-01

    The kinetics and mechanism of bisulfite addition to benzaldehyde were studied at low pH in order to assess the importance of this reaction in stabilizing S(IV) in fog-, cloud-, and rainwater. Previously, the authors established that appreciable concentrations of the formaldehyde-bisulfite adduct (HMSA) are often present in fogwater. Measured HMSA concentrations in fogwater often do not fully account for observed excess S(IV) concentrations, however, so that other S(IV)-aldehyde adducts may be present. Reaction rates were determined by monitoring the disappearance of benzaldehyde by U.V. spectrophotometry under pseudo-first order conditions, (S(IV))/sub T/ >>(phi-CHO)/sub T/, in the pH range 0 - 4.4 at 25/sup 0/C. The equilibrium constant was determined by dissolving the sodium salt of the addition compound in a solution adjusted to pH 3.9, and measuring the absorbance of the equilibrated solution at 250 nm. A literature value of the extinction coefficient for benzaldehyde was used to calculate the concentration of free benzaldehyde. All solutions were prepared under an N/sub 2/ atmosphere using deoxygenated, deionized water and ionic strength was maintained at 1.0 M with sodium chloride.

  8. Aldehyde-sequestering drugs: tools for studying protein damage by lipid peroxidation products.

    Science.gov (United States)

    Burcham, Philip C; Kaminskas, Lisa M; Fontaine, Frank R; Petersen, Dennis R; Pyke, Simon M

    2002-12-27

    Elevated levels of reactive alpha,beta-unsaturated aldehydes (e.g. malondialdehyde, 4-hydroxynonenal and acrolein) in the affected tissues of various degenerative conditions suggest these substances are active propagators of the disease process. One experimental approach to attenuating damage by these intermediates employs 'aldehyde-sequestering drugs' as sacrificial nucleophiles, thereby sparing cell macromolecules and perhaps slowing disease progression. Drugs with demonstrated trapping activity toward lipid-derived aldehydes include various amine compounds such as aminoguanidine, carnosine and pyridoxamine. We have focused on identifying scavengers of acrolein, perhaps the most toxic aldehyde formed during lipid peroxidation cascades. Various phthalazine compounds (hydralazine and dihydralazine) were found to trap acrolein readily, forming hydrazone derivatives in a rapid Schiff-type reaction. These compounds strongly protect against acrolein-mediated toxicity in isolated hepatocytes.

  9. Role of Lipid Peroxidation-Derived α, β-Unsaturated Aldehydes in Vascular Dysfunction

    Directory of Open Access Journals (Sweden)

    Seung Eun Lee

    2013-01-01

    Full Text Available Vascular diseases are the most prominent cause of death, and inflammation and vascular dysfunction are key initiators of the pathophysiology of vascular disease. Lipid peroxidation products, such as acrolein and other α, β-unsaturated aldehydes, have been implicated as mediators of inflammation and vascular dysfunction. α, β-Unsaturated aldehydes are toxic because of their high reactivity with nucleophiles and their ability to form protein and DNA adducts without prior metabolic activation. This strong reactivity leads to electrophilic stress that disrupts normal cellular function. Furthermore, α, β-unsaturated aldehydes are reported to cause endothelial dysfunction by induction of oxidative stress, redox-sensitive mechanisms, and inflammatory changes such as induction of cyclooxygenase-2 and cytokines. This review provides an overview of the effects of lipid peroxidation products, α, β-unsaturated aldehydes, on inflammation and vascular dysfunction.

  10. ENVIRONMENTAL TECHNOLOGY PROTOCOL VERIFICATION REPORT, EMISSIONS OF VOCS AND ALDEHYDES FROM COMMERCIAL FURNITURE (WITH APPENDICES)

    Science.gov (United States)

    As part of a U.S. Environmental Protection Agency Environmental Technology Verification program, the Research Triangle Institute (RTI) developed a test protocol for measuring volatile organic compounds and aldehydes in a large chamber. RTI convened stakeholders for the commercial...

  11. Direct chemoselective synthesis of glyconanoparticles from unprotected reducing glycans and glycopeptide aldehydes

    DEFF Research Database (Denmark)

    Thygesen, Mikkel Boas; Sørensen, Kasper Kildegaard; Cló, Emiliano

    2009-01-01

    Chemoselective oxime coupling was used for facile conjugation of unprotected, reducing glycans and glycopeptide aldehydes with core-shell gold nanoparticles carrying reactive aminooxy groups on the organic shell....

  12. Samarium Barbier reactions of alpha-iodomethyloxazoles and thiazoles with aliphatic aldehydes.

    Science.gov (United States)

    Williams, David R; Berliner, Martin A; Stroup, Bryan W; Nag, Partha P; Clark, Michael P

    2005-09-15

    [reaction: see text] The reductive coupling of substituted alpha-iodomethyloxazoles and thiazoles with aliphatic aldehydes under Barbier conditions provides an effective method for the direct incorporation of intact heterocyclic systems.

  13. Oxidative Esterification of Aldehydes with Urea Hydrogen Peroxide Catalyzed by Aluminum Chloride Hexahydrate

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sin-Ae; Kim, Yoon Mi; Lee, Jong Chan [Chung-Ang University, Seoul (Korea, Republic of)

    2016-08-15

    We have developed a new, environmentally benign and highly efficient oxidative preparation of methyl esters by the reaction of various aldehydes with UHP in methanol catalyzed by readily accessible aluminum(III) chloride hexahydrate. This new greener and cost effective direct esterification method can serve as a useful alternative to existing protocols. Esters are some of the most important functional groups in organic chemistry and have been found in the sub-structure of a variety of natural products, industrial chemicals, and pharmaceuticals. Numerous methods have been reported for the preparation of various esters. In particular, this method gives low yields for both aldehydes containing electron donating substituents in aromatic rings and heterocyclic aldehydes. Therefore, development of a more general, efficient, and greener protocol for the esterification of aldehydes with readily available catalyst is still desirable.

  14. Solvent-free oxidation of aldehydes to acids by TBHP using ...

    Indian Academy of Sciences (India)

    free oxidation of aldehydes to acids by TBHP using environmental-friendly MnO 4 − 1 -exchanged Mg-Al hydrotalcite catalyst ... Chemical Engineering and Process Development Division, National Chemical Laboratory, Pune 411 008, India ...

  15. Role of aldehydes in the toxic and mutagenic effects of nitrosamines

    OpenAIRE

    Peterson, Lisa A.; Urban, Anna M.; Vu, Choua C.; Cummings, Meredith E.; Brown, Lee C.; Warmka, Janel K.; Li, Li; Wattenberg, Elizabeth V.; Patel, Yesha; Stram, Daniel O.; Pegg, Anthony E.

    2013-01-01

    α-Hydroxynitrosamine metabolites of nitrosamines decompose to a reactive diazohydroxide and an aldehyde. To test the hypothesis that the aldehydes contribute to the harmful effects of nitrosamines, the toxic and mutagenic activity of three model methylating agents were compared in Chinese hamster ovary cells expressing human O6-alkylguanine DNA alkyltransferase (AGT) or not. N-Nitrosomethylurethane (NMUr), acetoxymethylmethylnitrosamine (AMMN) and 4-(methylnitrosamino)-4-acetoxy-1-(3-pyridyl)...

  16. Copper(II)/amine synergistically catalyzed enantioselective alkylation of cyclic N-acyl hemiaminals with aldehydes.

    Science.gov (United States)

    Sun, Shutao; Mao, Ying; Lou, Hongxiang; Liu, Lei

    2015-07-07

    The first catalytic asymmetric alkylation of N-acyl quinoliniums with aldehydes has been described. A copper/amine synergistic catalytic system has been developed, allowing the addition of functionalized aldehydes to a wide range of electronically varied N-acyl quinoliniums in good yields with excellent enantiocontrol. The synergistic catalytic system was also effective for N-acyl dihydroisoquinoliniums and β-caboliniums, demonstrating the general applicability of the protocol in the enantioselective alkylation of diverse cyclic N-acyl hemiaminals.

  17. An Improved Protocol for the Aldehyde Olefination Reaction Using (bmim ( as Reaction Medium

    Directory of Open Access Journals (Sweden)

    Vivek Srivastava

    2013-01-01

    Full Text Available [Ru(CODCl2]/CuCl2·2H2O/LiCl catalytic system works efficiently in ionic liquid media for aldehyde olefination reaction. It offers good yield and selectivity with the added advantage of 5 times recyclability for [Ru(CODCl2] /CuCl2·2H2O/LiCl catalytic system. We also successfully reduced the reaction time from 12 hours to 9 hours for the aldehyde olefination reaction.

  18. N-heterocyclic carbene catalyzed additions of 3-trimethylsilyl propiolate to aldehydes

    Directory of Open Access Journals (Sweden)

    Guang-Fen Du

    2016-03-01

    Full Text Available A N-heterocyclic carbene (NHC catalyzed addition reaction of 3-trimethylsilyl propiolate with aldehydes has been developed. Under the catalysis of 2 mol% NHCs, benzaldehyde, furfural, β-naphthaldehyde, meta- and para-substituted aromatic aldehydes reacted with 3-trimethylsilyl propiolate to afford β-acylated MBH adducts in good yield with excellent stereoselectivity. While ortho-substituted benzaldehydes coupled with 3-trimethylsilyl propiolate to give alkynylation products as the sole products under the same reaction conditions.

  19. Oxidation of Group 8 transition-Metal Hydrides and Ionic Hydrogenation of Ketones and Aldehydes

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kjell-Tore

    1996-08-01

    Transition-metal hydrides have received considerable attention during the last decades because of their unusual reactivity and their potential as homogeneous catalysts for hydrogenation and other reactions of organic substrates. An important class of catalytic processes where transition-metal hydrides are involved is the homogeneous hydrogenation of alkenes, alkynes, ketones, aldehydes, arenes and nitro compounds. This thesis studies the oxidation of Group 8 transition-metal hydrides and the ionic hydrogenation of ketones and aldehydes.

  20. Effect of selected aldehydes on the growth and fermentation of ethanologenic Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Zaldivar, J.; Ingram, L.O. [Univ. of Florida, Gainesville (United States). Dept. of Microbiology and Cell Science; Martinez, A. [Univ. of Florida, Gainesville (United States). Dept. of Microbiology and Cell Science]|[Univ. Nacional Autonoma de Mexico (Mexico). Inst. de Biotecnologia

    1999-10-05

    Bioethanol production from lignocellulosic raw-materials requires the hydrolysis of carbohydrate polymers into a fermentable syrup. During the hydrolysis of hemicellulose with dilute acid, a variety of toxic compounds are produced such as soluble aromatic aldehydes from lignin and furfural from pentose destruction. In this study, the authors have investigated the toxicity of representative aldehydes (furfural, 5-hydroxymethlyfurfural, 4-hydroxybenzaldehyde, syringaldehyde, and vanillin) as inhibitors of growth and ethanol production by ethanologenic derivatives of Escherichia coli B (strains K011 and LY01). Aromatic aldyhydes were at least twice as toxic as furfural of 5-hydroxymethylfurfural on a weight basis. The toxicities of all aldehydes (and ethanol) except furfural were additive when tested in binary combinations. In all cases, combinations with furfural were unexpectedly toxic. Although the potency of these aldehydes was directly related to hydrophobicity indicating a hydrophobic site of action, none caused sufficient membrane damage to allow the leakage of intracellular magnesium even when present at sixfold the concentrations required for growth inhibition. Of the aldehydes tested, only furfural strongly inhibited ethanol production in vitro. A comparison with published results for other microorganisms indicates that LY01 is equivalent or more resistant than other biocatalysts to the aldehydes examined in this study.

  1. In vitro-in vivo correlation for intrinsic clearance for drugs metabolized by human aldehyde oxidase.

    Science.gov (United States)

    Zientek, Michael; Jiang, Ying; Youdim, Kuresh; Obach, R Scott

    2010-08-01

    The ability to predict in vivo clearance from in vitro intrinsic clearance for compounds metabolized by aldehyde oxidase has not been demonstrated. To date, there is no established scaling method for predicting aldehyde oxidase-mediated clearance using in vitro or animal data. This challenge is exacerbated by the fact that rats and dogs, two of the laboratory animal species commonly used to develop in vitro-in vivo correlations of clearance, differ from humans with regard to expression of aldehyde oxidase. The objective of this investigation was to develop an in vitro-in vivo correlation of intrinsic clearance for aldehyde oxidase, using 11 drugs known to be metabolized by this enzyme. The set consisted of methotrexate, XK-469, (+/-)-4-(4-cyanoanilino)-5,6-dihydro-7-hydroxy-7H-cyclopenta[d]pyrimidine (RS-8359), zaleplon, 6-deoxypenciclovir, zoniporide, O(6)-benzylguanine, N-[(2'-dimethylamino)ethyl]acridine-4-carboxamide (DACA), carbazeran, PF-4217903, and PF-945863. These compounds were assayed using two in vitro systems (pooled human liver cytosol and liver S-9 fractions) to calculate scaled unbound intrinsic clearance, and they were then compared with calculated in vivo unbound intrinsic clearance. The investigation provided a relative scale that can be used for in vitro-in vivo correlation of aldehyde oxidase clearance and suggests limits as to when a potential new drug candidate that is metabolized by this enzyme will possess acceptable human clearance, or when structural modification is required to reduce aldehyde oxidase catalyzed metabolism.

  2. O-Alkyl Hydroxamates as Metaphors of Enzyme-Bound Enolate Intermediates in Hydroxy Acid Dehydrogenases. Inhibitors of Isopropylmalate Dehydrogenase, Isocitrate Dehydrogenase, and Tartrate Dehydrogenase(1).

    Science.gov (United States)

    Pirrung, Michael C.; Han, Hyunsoo; Chen, Jrlung

    1996-07-12

    The inhibition of Thermus thermophilus isopropylmalate dehydrogenase by O-methyl oxalohydroxamate was studied for comparison to earlier results of Schloss with the Salmonella enzyme. It is a fairly potent (1.2 &mgr;M), slow-binding, uncompetitive inhibitor against isopropylmalate and is far superior to an oxamide (25 mM K(i) competitive) that is isosteric with the ketoisocaproate product of the enzyme. This improvement in inhibition was attributed to its increased NH acidity, which presumably is due to the inductive effect of the hydroxylamine oxygen. This principle was extended to the structurally homologous enzyme isocitrate dehydrogenase from E. coli, for which the compound O-(carboxymethyl) oxalohydroxamate is a 30 nM inhibitor, uncompetitive against isocitrate. The pH dependence of its inhibition supports the idea that it is bound to the enzyme in the anionic form. Another recently discovered homologous enzyme, tartrate dehydrogenase from Pseudomonas putida, was studied with oxalylhydroxamate. It has a relatively low affinity for the enzyme, though it is superior to tartrate. On the basis of these leads, squaric hydroxamates with increased acidity compared to squaric amides directed toward two of these enzymes were prepared, and they also show increased inhibitory potency, though not approaching the nanomolar levels of the oxalylhydroxamates.

  3. Structural Determinants of Oligomerization of !1-Pyrroline-5-Carboxylate Dehydrogenase: Identification of a Hexamerization Hot Spot

    Science.gov (United States)

    Luo, Min; Singh, Ranjan K.; Tanner, John J.

    2013-01-01

    The aldehyde dehydrogenase (ALDH) superfamily member !1-pyrroline-5-carboxylate dehydrogenase (P5CDH) catalyzes the NAD+-dependent oxidation of glutamate semialdehyde to glutamate, which is the final step of proline catabolism. Defects in P5CDH activity lead to the metabolic disorder type II hyperprolinemia, P5CDH is essential for virulence of the fungal pathogen Cryptococcus neoformans, and bacterial P5CDHs have been targeted for vaccine development. Although the enzyme oligomeric state is known to be important for ALDH function, the oligomerization of P5CDH has remained relatively unstudied. Here we determine the oligomeric states and quaternary structures of four bacterial P5CDHs using a combination of small-angle X-ray scattering, X-ray crystallography, and dynamic light scattering. The P5CDHs from Thermus thermophilus and Deinococcus radiodurans form trimer-of-dimers hexamers in solution, which is the first observation of a hexameric ALDH in solution. In contrast, two Bacillus P5CDHs form dimers in solution but do not assemble into a higher order oligomer. Site-directed mutagenesis was used to identify a hexamerization hot spot that is centered on an arginine residue in the NAD+-binding domain. Mutation of this critical Arg residue to Ala in either of the hexameric enzymes prevents hexamer formation in solution. Paradoxically, the dimeric Arg-to-Ala T. thermophilus mutant enzyme packs as a hexamer in the crystal state, which illustrates the challenges associated with predicting the biological assembly in solution from crystal structures. The observation of different oligomeric states among P5CDHs suggests potential differences in cooperativity and protein-protein interactions. PMID:23747974

  4. E1 of α-ketoglutarate dehydrogenase defends Mycobacterium tuberculosis against glutamate anaplerosis and nitroxidative stress.

    Science.gov (United States)

    Maksymiuk, Christina; Balakrishnan, Anand; Bryk, Ruslana; Rhee, Kyu Y; Nathan, Carl F

    2015-10-27

    Enzymes of central carbon metabolism (CCM) in Mycobacterium tuberculosis (Mtb) make an important contribution to the pathogen's virulence. Evidence is emerging that some of these enzymes are not simply playing the metabolic roles for which they are annotated, but can protect the pathogen via additional functions. Here, we found that deficiency of 2-hydroxy-3-oxoadipate synthase (HOAS), the E1 component of the α-ketoglutarate (α-KG) dehydrogenase complex (KDHC), did not lead to general metabolic perturbation or growth impairment of Mtb, but only to the specific inability to cope with glutamate anaplerosis and nitroxidative stress. In the former role, HOAS acts to prevent accumulation of aldehydes, including growth-inhibitory succinate semialdehyde (SSA). In the latter role, HOAS can participate in an alternative four-component peroxidase system, HOAS/dihydrolipoyl acetyl transferase (DlaT)/alkylhydroperoxide reductase colorless subunit gene (ahpC)-neighboring subunit (AhpD)/AhpC, using α-KG as a previously undescribed source of electrons for reductase action. Thus, instead of a canonical role in CCM, the E1 component of Mtb's KDHC serves key roles in situational defense that contribute to its requirement for virulence in the host. We also show that pyruvate decarboxylase (AceE), the E1 component of pyruvate dehydrogenase (PDHC), can participate in AceE/DlaT/AhpD/AhpC, using pyruvate as a source of electrons for reductase action. Identification of these systems leads us to suggest that Mtb can recruit components of its CCM for reactive nitrogen defense using central carbon metabolites.

  5. Purification and properties of a 3 alpha-hydroxysteroid dehydrogenase of rat liver cytosol and its inhibition by anti-inflammatory drugs.

    Science.gov (United States)

    Penning, T M; Mukharji, I; Barrows, S; Talalay, P

    1984-01-01

    An NAD(P)-dependent 3 alpha-hydroxysteroid dehydrogenase (EC 1.1.1.50) was purified to homogeneity from rat liver cytosol, where it is responsible for most if not all of the capacity for the oxidation of androsterone, 1-acenaphthenol and benzenedihydrodiol (trans-1,2-dihydroxycyclohexa-3,5-diene). The dehydrogenase has many properties (substrate specificity, pI, Mr, amino acid composition) in common with the dihydrodiol dehydrogenase (EC 1.3.1.20) purified from the same source [Vogel, Bentley, Platt & Oesch (1980) J. Biol. Chem. 255, 9621-9625]. Since 3 alpha-hydroxysteroids are by far the most efficient substrates, the enzyme is more appropriately designated a 3 alpha-hydroxysteroid dehydrogenase. It also promotes the NAD(P)H-dependent reductions of quinones (e.g. 9,10-phenanthrenequinone, 1,4-benzoquinone), aromatic aldehydes (4-nitrobenzaldehyde) and aromatic ketones (4-nitroacetophenone). The dehydrogenase is not inhibited by dicoumarol, disulfiram, hexobarbital or pyrazole. The mechanism of the powerful inhibition of this enzyme by both non-steroidal and steroidal anti-inflammatory drugs [Penning & Talalay (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 4504-4508] was examined with several substrates. Most non-steroidal anti-inflammatory drugs are competitive inhibitors (e.g. Ki for indomethacin, 0.20 microM for 9,10-phenanthrenequinone reduction at pH 6.0, and 0.835 microM for androsterone oxidation at pH 7.0), except for salicylates, which act non-competitively (e.g. Ki for aspirin, 650 microM for androsterone oxidation). The inhibitory potency of these agents falls sharply as the pH is increased from 6 to 9. Most anti-inflammatory steroids are likewise competitive inhibitors, except for the most potent (betamethasone and dexamethasone), which act non-competitively. The enzyme is inhibited competitively by arachidonic acid and various prostaglandins. PMID:6435601

  6. Succinic semialdehyde dehydrogenase deficiency, a disorder of GABA metabolism: an update on pharmacological and enzyme-replacement therapeutic strategies.

    Science.gov (United States)

    Vogel, Kara R; Ainslie, Garrett R; Walters, Dana C; McConnell, Alice; Dhamne, Sameer C; Rotenberg, Alexander; Roullet, Jean-Baptiste; Gibson, K Michael

    2018-02-19

    We present an update to the status of research on succinic semialdehyde dehydrogenase (SSADH) deficiency (SSADHD), a rare disorder of GABA metabolism. This is an unusual disorder featuring the accumulation of both GABA and its neuromodulatory analog, gamma-hydroxybutyric acid (GHB), and recent studies have advanced the potential clinical application of NCS-382, a putative GHB receptor antagonist. Animal studies have provided proof-of-concept that enzyme replacement therapy could represent a long-term therapeutic option. The characterization of neuronal stem cells (NSCs) derived from aldehyde dehydrogenase 5a1 -/- (aldh5a1 -/- ) mice, the murine model of SSADHD, has highlighted NSC utility as an in vitro system in which to study therapeutics and associated toxicological properties. Gene expression analyses have revealed that transcripts encoding GABA A receptors are down-regulated and may remain largely immature in aldh5a1 -/- brain, characterized by excitatory as opposed to inhibitory outputs, the latter being the expected action in the mature central nervous system. This indicates that agents altering chloride channel activity may be therapeutically relevant in SSADHD. The most recent therapeutic prospects include mTOR (mechanistic target of rapamycin) inhibitors, drugs that have received attention with the elucidation of the effects of elevated GABA on autophagy. The outlook for novel therapeutic trials in SSADHD continues to improve.

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

    Science.gov (United States)

    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

  8. Identification and characterization of an antennae-specific aldehyde oxidase from the navel orangeworm.

    Directory of Open Access Journals (Sweden)

    Young-Moo Choo

    Full Text Available Antennae-specific odorant-degrading enzymes (ODEs are postulated to inactivate odorant molecules after they convey their signal. Different classes of insect ODEs are specific to esters, alcohols, and aldehydes--the major functional groups of female-produced, hydrophobic sex pheromones from moth species. Esterases that rapidly inactive acetate and other esters have been well-studied, but less is known about aldehyde oxidases (AOXs. Here we report cloning of an aldehyde oxidase, AtraAOX2, from the antennae of the navel orangeworm (NOW, Amyelois transitella, and the first activity characterization of a recombinant insect AOX. AtraAOX2 gene spans 3,813 bp and encodes a protein with 1,270 amino acid residues. AtraAOX2 cDNA was expressed in baculovirus-infected insect Sf21 cells as a ≈280 kDa homodimer with 140 kDa subunits. Recombinant AtraAOX2 degraded Z11Z13-16Ald and plant volatile aldehydes as substrates. However, as expected for aldehyde oxidases, recombinant AtraAOX2 did not show specificity for Z11Z13-16Ald, the main constituent of the sex pheromone, but showed high activity for plant volatile aldehydes. Our data suggest AtraAOX2 might be involved in degradation of a diversity of aldehydes including sex pheromones, plant-derived semiochemicals, and chemical cues for oviposition sites. Additionally, AtraAOX2 could protect the insect's olfactory system from xenobiotics, including pesticides that might reach the sensillar lymph surrounding the olfactory receptor neurons.

  9. Chemo- and Diastereoselective N-Heterocyclic Carbene-Catalyzed Cross-Benzoin Reactions Using N-Boc-α-amino Aldehydes.

    Science.gov (United States)

    Haghshenas, Pouyan; Gravel, Michel

    2016-09-16

    N-Boc-α-amino aldehydes are shown to be excellent partners in cross-benzoin reactions with aliphatic or heteroaromatic aldehydes. The chemoselectivity of the reaction and the facial selectivity on the amino aldehyde allow cross-benzoin products to be obtained in good yields and good diastereomeric ratios. The developed method is utilized as the key step in a concise total synthesis of d-arabino-phytosphingosine.

  10. Major differences exist in the function and tissue-specific expression of human aflatoxin B1 aldehyde reductase and the principal human aldo-keto reductase AKR1 family members.

    Science.gov (United States)

    O'connor, T; Ireland, L S; Harrison, D J; Hayes, J D

    1999-01-01

    Complementary DNA clones encoding human aflatoxin B(1) aldehyde reductase (AKR7A2), aldehyde reductase (AKR1A1), aldose reductase (AKR1B1), dihydrodiol dehydrogenase 1 (AKR1C1) and chlordecone reductase (AKR1C4) have been expressed in Escherichia coli. These members of the aldo-keto reductase (AKR) superfamily have been purified from E. coli as recombinant proteins. The recently identified AKR7A2 was shown to differ from the AKR1 isoenzymes in being able to catalyse the reduction of 2-carboxybenzaldehyde. Also, AKR7A2 was found to exhibit a narrow substrate specificity, with activity being restricted to succinic semialdehyde (SSA), 2-nitrobenzaldehyde, pyridine-2-aldehyde, isatin, 1,2-naphthoquinone (1,2-NQ) and 9,10-phenanthrenequinone. In contrast, AKR1A1 reduces a broad spectrum of carbonyl-containing compounds, displaying highest specific activity for SSA, 4-carboxybenzaldehyde, 4-nitrobenzaldehyde, pyridine-3-aldehyde, pyridine-4-aldehyde, 4-hydroxynonenal, phenylglyoxal, methylglyoxal, 2,3-hexanedione, 1, 2-NQ, 16-ketoestrone and d-glucuronic acid. Comparison between the kinetic properties of AKR7A2 and AKR1A1 showed that both recombinant enzymes exhibited roughly similar k(cat)/K(m) values for SSA, 1,2-NQ and 16-ketoestrone. Many of the compounds which are substrates for AKR1A1 also serve as substrates for AKR1B1, though the latter enzyme was shown to display a specific activity significantly less than that of AKR1A1 for most of the aromatic and aliphatic aldehydes studied. Neither AKR1C1 nor AKR1C4 was found to possess high reductase activity towards aliphatic aldehydes, aromatic aldehydes, aldoses or dicarbonyls. However, unlike AKR1A1 and AKR1B1, both AKR1C1 and AKR1C4 were able to catalyse the oxidation of 1-acenaphthenol and, in addition, AKR1C4 could oxidize di- and tri-hydroxylated bile acids. Specific antibodies raised against AKR7A2, AKR1A1, AKR1B1, AKR1C1 and AKR1C4 have been used to show the presence of all of the reductases in human hepatic

  11. Red Xylem and Higher Lignin Extractability by Down-Regulating a Cinnamyl Alcohol Dehydrogenase in Poplar.

    Science.gov (United States)

    Baucher, M.; Chabbert, B.; Pilate, G.; Van Doorsselaere, J.; Tollier, M. T.; Petit-Conil, M.; Cornu, D.; Monties, B.; Van Montagu, M.; Inze, D.; Jouanin, L.; Boerjan, W.

    1996-12-01

    Cinnamyl alcohol dehydrogenase (CAD) catalyzes the last step in the biosynthesis of the lignin precursors, the monolignols. We have down-regulated CAD in transgenic poplar (Populus tremula X Populus alba) by both antisense and co-suppression strategies. Several antisense and sense CAD transgenic poplars had an approximately 70% reduced CAD activity that was associated with a red coloration of the xylem tissue. Neither the lignin amount nor the lignin monomeric composition (syringyl/guaiacyl) were significantly modified. However, phloroglucinol-HCl staining was different in the down-regulated CAD plants, suggesting changes in the number of aldehyde units in the lignin. Furthermore, the reactivity of the cell wall toward alkali treatment was altered: a lower amount of lignin was found in the insoluble, saponified residue and more lignin could be precipitated from the soluble alkali fraction. Moreover, large amounts of phenolic compounds, vanillin and especially syringaldehyde, were detected in the soluble alkali fraction of the CAD down-regulated poplars. Alkaline pulping experiments on 3-month-old trees showed a reduction of the kappa number without affecting the degree of cellulose degradation. These results indicate that reducing the CAD activity in trees might be a valuable strategy to optimize certain processes of the wood industry, especially those of the pulp and paper industry.

  12. Cloning, expression and characterization of alcohol dehydrogenases in the silkworm Bombyx mori

    Directory of Open Access Journals (Sweden)

    Nan Wang

    2011-01-01

    Full Text Available Alcohol dehydrogenases (ADH are a class of enzymes that catalyze the reversible oxidation of alcohols to corresponding aldehydes or ketones, by using either nicotinamide adenine dinucleotide (NAD or nicotinamide adenine dinucleotide phosphate (NADP, as coenzymes. In this study, a short-chain ADH gene was identified in Bombyx mori by 5'-RACE PCR. This is the first time the coding region of BmADH has been cloned, expressed, purified and then characterized. The cDNA fragment encoding the BmADH protein was amplified from a pool of silkworm cDNAs by PCR, and then cloned into E. coli expression vector pET-30a(+. The recombinant His-tagged BmADH protein was expressed in E. coli BL21 (DE3, and then purified by metal chelating affinity chromatography. The soluble recombinant BmADH, produced at low-growth temperature, was instrumental in catalyzing the ethanol-dependent reduction of NAD+, thereby indicating ethanol as one of the substrates of BmADH.

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

    Science.gov (United States)

    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.

  14. Quantification of aldehydes emissions from alternative and renewable aviation fuels using a gas turbine engine

    Science.gov (United States)

    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.

  15. Thermal, Catalytic Conversion of Alkanes to Linear Aldehydes and Linear Amines.

    Science.gov (United States)

    Tang, Xinxin; Jia, Xiangqing; Huang, Zheng

    2018-03-21

    Alkanes, the main constituents of petroleum, are attractive feedstocks for producing value-added chemicals. Linear aldehydes and amines are two of the most important building blocks in the chemical industry. To date, there have been no effective methods for directly converting n-alkanes to linear aldehydes and linear amines. Here, we report a molecular dual-catalyst system for production of linear aldehydes via regioselective carbonylation of n-alkanes. The system is comprised of a pincer iridium catalyst for transfer-dehydrogenation of the alkane using t-butylethylene or ethylene as a hydrogen acceptor working sequentially with a rhodium catalyst for olefin isomerization-hydroformylation with syngas. The system exhibits high regioselectivity for linear aldehydes and gives high catalytic turnover numbers when using ethylene as the acceptor. In addition, the direct conversion of light alkanes, n-pentane and n-hexane, to siloxy-terminated alkyl aldehydes through a sequence of Ir/Fe-catalyzed alkane silylation and Ir/Rh-catalyzed alkane carbonylation, is described. Finally, the Ir/Rh dual-catalyst strategy has been successfully applied to regioselective alkane aminomethylation to form linear alkyl amines.

  16. Direct site-specific immobilization of protein A via aldehyde-hydrazide conjugation.

    Science.gov (United States)

    Zang, Berlin; Ren, Jun; Xu, Li; Jia, Lingyun

    2016-01-01

    Immobilization of affinity ligands on supporting matrices is a key step for the preparation of affinity chromatography resins, and an efficient coupling strategy can significantly improve the validity and cost of the affinity system, especially for systems that employ expensive recombinant proteins or antibodies as affinity ligands. This study described a simple method for obtaining site-specific immobilization of protein A (the ligand) via aldehyde-hydrazide conjugation and its application in antibody purification via protein A chromatography. An aldehyde group was generated at the N-terminus of protein A in vivo by co-expressing a formylglycine-generating enzyme (FGE) and recombinant protein A containing a FGE recognizing sequence (aldehyde tag) in Escherichia coli. The resulting aldehyde allowed direct immobilization of protein A onto the hydrazide-modified agarose matrices under mild condition. We found that 100mM aniline was most effective for catalyzing the coupling reaction, and the recombinant protein A could be coupled with high selectivity, directly from a crude cell extract. The site-specific immobilized protein A showed good capacity for antibody purification. The specificity of the aldehyde-hydrazide reaction not only allowed site-specific immobilization of affinity ligands, but also improved the cost of the process by employing unpurified ligands, a method that might be of great use to industrial applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Effects of light and copper ions on volatile aldehydes of milk and milk fractions

    Energy Technology Data Exchange (ETDEWEB)

    Jeno, W.; Bassette, R.; Crang, R.E.

    1988-09-01

    Raw, laboratory-pasteurized and plant-pasteurized homogenized milks were exposed to copper ions (5 ppm), to sunlight or fluorescent light and the effects determined on the composition of volatile aldehydes. The greatest change due to copper treatment was an increase in n-hexanal; acetaldehyde showed the least response in each of the sources of milk. The responses were similar from all three sources of milk with laboratory-pasteurized milk samples showing the greatest responses for each aldehyde analyzed. Similar milk samples exposed to sunlight also showed an increase in volatile aldehydes from all milk sources but with the greatest response being acetaldehyde and n-pentanal components. The milk fraction most susceptible to changes in the presence of light was neutralized whey, whereas resuspended cream was most susceptible to copper exposure. Overall, dialyzed whey appeared to be influenced more than other milk fractions by both light and copper ions.

  18. Catalytic production of methyl acrylates by gold-mediated cross coupling of unsaturated aldehydes with methanol

    Science.gov (United States)

    Karakalos, Stavros; Zugic, Branko; Stowers, Kara J.; Biener, Monika M.; Biener, Juergen; Friend, Cynthia M.; Madix, Robert J.

    2016-10-01

    Modern methods of esterification, one of the most important reactions in organic synthesis, are reaching their limits, as far as waste and expense are concerned. Novel chemical approaches to ester formation are therefore of importance. Here we report a simple procedure free of caustic reagents or byproducts for the facile direct oxidative methyl esterification of aldehydes over nanoporous Au catalysts. Complementary model studies on single crystal gold surfaces establish the fundamental reactions involved. We find that methanol more readily reacts with adsorbed active oxygen than do the aldehydes, but that once the aldehydes do react, they form strongly-bound acrylates that block reactive sites and decrease the yields of acrylic esters under steady flow conditions at 420 K. Significant improvements in yield can be achieved by operating at higher temperatures, which render the site-blocking acrylates unstable.

  19. Functional screening of aldehyde decarbonylases for long-chain alkane production by Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Kang, Min-Kyoung; Zhou, Yongjin J.; Buijs, Nicolaas A.

    2017-01-01

    performed functional screening to identify efficient ADs that can improve alkane production by S. cerevisiae. Results: A comparative study of ADs originated from a plant, insects, and cyanobacteria were conducted in S. cerevisiae. As a result, expression of aldehyde deformylating oxygenases (ADOs), which......Background: Low catalytic activities of pathway enzymes are often a limitation when using microbial based chemical production. Recent studies indicated that the enzyme activity of aldehyde decarbonylase (AD) is a critical bottleneck for alkane biosynthesis in Saccharomyces cerevisiae. We therefore...... are cyanobacterial ADs, from Synechococcus elongatus and Crocosphaera watsonii converted fatty aldehydes to corresponding Cn-1 alkanes and alkenes. The CwADO showed the highest alkane titer (0.13 mg/L/OD600) and the lowest fatty alcohol production (0.55 mg/L/OD600). However, no measurable alkanes and alkenes were...

  20. Simulation of Aldehyde Emissions from an Ethanol Fueled Spark Ignition Engine and Comparison with FTIR Measurements

    International Nuclear Information System (INIS)

    Zaránte, Paola Helena Barros; Sodre, Jose Ricardo

    2016-01-01

    This paper presents a mathematical model that calculates aldehyde emissions in the exhaust of a spark ignition engine fueled with ethanol. The numerical model for aldehyde emissions was developed using FORTRAN software, with the input data obtained from a dedicated engine cycle simulation software, AVL BOOST. The model calculates formaldehyde and acetaldehyde emissions, formed from the partial oxidation of methane, ethane and unburned ethanol. The calculated values were compared with experimental data obtained by Fourier Transform Infrared Spectroscopy (FTIR). The experiments were performed with a mid-size sedan powered by a 1.4-liter spark ignition engine on a chassis dynamometer. In general, the results demonstrate that the concentrations of aldehydes and the source elements increased with engine speed and exhaust gas temperature. A reasonable agreement between simulated and measured values was achieved. (paper)

  1. Organic acids and aldehydes in rainwater in a northwest region of Spain

    Energy Technology Data Exchange (ETDEWEB)

    Pena, R.M.; Garcia, S.; Herrero, C. [Universidad de Santiago de Compostela, Lugo (Spain). Departamento de Quimica Analitica, Nutricion y Bromatologia

    2002-11-01

    During a 1 year period, measurements of carboxylic acids and aldehydes were carried out in rainwater samples collected at nine different sites in NW Spain surrounding a thermal power plant in order to determine concentration levels and sources. In addition, certain major ions (Cl{sup -}, NO{sub 3}{sup -}, SO{sub 4}{sup 2-}, Na{sup +}, NH{sub 4}{sup +}, K{sup +}, Mg{sup 2+}, Ca{sup 2+}) were also determined. Aldehyde and carboxylic acid concentration patterns and their effects on rainwater composition concerning temporal, seasonal and spatial variations were evaluated. Among carboxylic acids, formic and acetic were predominant (VWA 7.0 and 8.3 {mu}M), while formaldehyde and acroleine were the dominant aldehydes (VWA 0.42 and 1.25 {mu}M). Carboxylic acids were estimated to account for 27.5% of the total free acidity (TFA), whereas sulphuric and nitric acid accounted for 46.2% and 26.2%, respectively. Oxalic acid was demonstrated to be an important contributing compound to the acidification in rainwater representing 7.1% of the TFA. The concentration of aldehydes and carboxylic acids, which originated mainly from biogenic emissions in the area studied, was strongly dependent on the season of the year (growing and non-growing). The ratios of formic to acetic acids are considerably different in the two seasons suggesting that there exist distinct sources in both growing and non-growing seasons. Principal component analysis was applied in order to elucidate the sources of aldehydes and organic acids in rainwater. The prevalence of natural vegetative origins for both of these compounds versus anthropogenic emissions was demonstrated and the importance of the oxidation of aldehydes as a relevant source of organic acids was also established. (author)

  2. Formation and accumulation of acetaldehyde and Strecker aldehydes during red wine oxidation

    Science.gov (United States)

    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 (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 catechin. All this makes that this aldehyde accumulates with intensity, particularly in young wines, shortly after wine

  3. Formation and Accumulation of Acetaldehyde and Strecker Aldehydes during Red Wine Oxidation

    Directory of Open Access Journals (Sweden)

    Mónica Bueno

    2018-02-01

    Full Text Available 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

  4. Aldehyde stress-mediated novel modification of proteins: epimerization of the N-terminal amino acid.

    Science.gov (United States)

    Kajita, Ryo; Goto, Takaaki; Lee, Seon Hwa; Oe, Tomoyuki

    2013-12-16

    Various kinds of aldehyde-mediated chemical modifications of proteins have been identified as being exclusively covalent. We report a unique noncovalent modification: the aldehyde-mediated epimerization of the N-terminal amino acid. Epimerization of amino acids is thought to cause conformational changes that alter their biological activity. However, few mechanistic studies have been performed, because epimerization of an amino acid is a miniscule change in a whole protein. Furthermore, it does not produce a mass shift, making mass spectrometric analysis difficult. Here, we have demonstrated epimerization mediated by endogenous aldehydes. A model peptide, with an N-terminal l- or d-FMRFamide, was incubated with an endogenous or synthetic aldehyde [acetaldehyde, methylglyoxal, pyridoxal 5'-phosphate (PLP), 4-oxo-2(E)-nonenal, 4-hydroxy-2(E)-nonenal, d-glucose (Glc), 4- or 2-pyridinecarboxaldehyde] under physiological conditions. Each reaction mixture was analyzed by liquid chromatography with ultraviolet detection and/or electrospray ionization mass spectrometry. Considerable epimerization occurred after incubation with some endogenous aldehydes (PLP, 40.6% after 1 day; Glc with copper ions, 6.5% after 7 days). Moreover, the epimerization also occurred in whole proteins (human serum albumin and PLP, 26.3% after 1 day). Tandem mass spectrometric studies, including deuterium labeling and sodium borohydride reduction, suggested that the epimerization results from initial Schiff base formation followed by tautomerization to ketimine that causes the chirality to be lost. This suggests that the epimerization of the N-terminal amino acid can also occur in vivo as a post-translational modification under a high level of aldehyde stress.

  5. Formation and Accumulation of Acetaldehyde and Strecker Aldehydes during Red Wine Oxidation

    Science.gov (United States)

    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 (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 from catechin. All this makes that this aldehyde accumulates with intensity, particularly in young wines, shortly after

  6. Ubiquitin-aldehyde: a general inhibitor of ubiquitin-recycling processes

    International Nuclear Information System (INIS)

    Hershko, A.; Rose, I.A.

    1987-01-01

    The generation and characterization of ubiquitin (Ub)-aldehyde, a potent inhibitor of Ub-C-terminal hydrolase, has previously been reported. The authors examine the action of this compound on the Ub-mediated proteolytic pathway using the system derived from rabbit reticulocytes. Addition of Ub-aldehyde was found to strongly inhibit breakdown of added 125 I-labeled lysozyme, but inhibition was overcome by increasing concentrations of Ub. The following evidence shows the effect of Ub-aldehyde on protein breakdown to be indirectly caused by its interference with the recycling of Ub, leading to exhaustion of the supply of free Ub: (i) Ub-aldehyde markedly increased the accumulation of Ub-protein conjugates coincident with a much decreased rate of conjugate breakdown; (ii) release of Ub from isolated Ub-protein conjugates in the absence of ATP (and therefore not coupled to protein degradation) is markedly inhibited by Ub-aldehyde. On the other hand, the ATP-dependent degradation of the protein moiety of Ub conjugates, which is an integral part of the proteolytic process, is not inhibited by this agent; (iii) direct measurement of levels of free Ub showed a rapid disappearance caused by the inhibitor. The Ub is found to be distributed in derivatives of a wide range of molecular weight classes. It thus seems that Ub-aldehyde, previously demonstrated to inhibit the hydrolysis of Ub conjugates of small molecules, also inhibits the activity of a series of enzymes that regenerate free Ub from adducts with proteins and intermediates in protein breakdown

  7. Syntheses of strychnine, norfluorocurarine, dehydrodesacetylretuline, and valparicine enabled by intramolecular cycloadditions of Zincke aldehydes.

    Science.gov (United States)

    Martin, David B C; Nguyen, Lucas Q; Vanderwal, Christopher D

    2012-01-06

    A full account of the development of the base-mediated intramolecular Diels-Alder cycloadditions of tryptamine-derived Zincke aldehydes is described. This important complexity-generating transformation provides the tetracyclic core of many indole monoterpene alkaloids in only three steps from commercially available starting materials and played a key role in short syntheses of norfluorocurarine (five steps), dehydrodesacetylretuline (six steps), valparicine (seven steps), and strychnine (six steps). Reasonable mechanistic possibilities for this reaction, a surprisingly facile dimerization of the products, and an unexpected cycloreversion to regenerate Zincke aldehydes under specific conditions are also discussed.

  8. Size-Selective Oxidation of Aldehydes with Zeolite Encapsulated Gold Nanoparticles

    DEFF Research Database (Denmark)

    Højholt, Karen Thrane; Laursen, Anders Bo; Kegnæs, Søren

    2011-01-01

    Here, we report a synthesis and catalytic study of hybrid materials comprised of 1–3 nm sinter-stable Au nanoparticles in MFI-type zeolites. An optional post-treatment in aqua regia effectively remove Au from the external surfaces. The size-selective aerobic aldehyde oxidation verifies that the a......Here, we report a synthesis and catalytic study of hybrid materials comprised of 1–3 nm sinter-stable Au nanoparticles in MFI-type zeolites. An optional post-treatment in aqua regia effectively remove Au from the external surfaces. The size-selective aerobic aldehyde oxidation verifies...

  9. Tandem Three-Component Reactions of Aldehyde, Alkyl Acrylate, and Dialkylmalonate Catalyzed by Ethyl Diphenylphosphine

    Directory of Open Access Journals (Sweden)

    Utpal Das

    2012-03-01

    Full Text Available A new highly efficient three-component reaction of alkyl acrylate, aldehyde and dialkyl malonate using ethyl diphenylphosphine as organocatalyst has been described. Various highly functional compounds bearing hydroxyl groups and the ester functions can be easily prepared in moderate to good yields according to our one-step procedure. The reactions are believed to proceed via Morita-Baylis-Hillman reactions of alkyl acrylate and aldehydes, followed by the Michael addition reactions of dialkyl malonates. Our reactions indicated that the intermediate species formed in the phosphine-catalyzed MBH reaction are an effective organic base to catalyze the Michael addition reactions of dialkyl malonates to the preformed MBH adducts.

  10. Protective vaccination against murine visceral leishmaniasis using aldehyde-containing Quillaja saponaria sapogenins.

    Science.gov (United States)

    Palatnik de Sousa, C B; Santos, W R; Casas, C P; Paraguai de Souza, E; Tinoco, L W; da Silva, B P; Palatnik, M; Parente, J P

    2004-06-23

    The presence of aldehyde groups at C-23 and C-24 of the triterpen aglycon moiety was disclosed in 1H NMR spectra of both the Riedel de Haen saponin (R) (delta 9.336) and Quillaja saponaria QuilA saponin (delta 9.348). The sign of the C-28 acylated linked moiety (delta 176) was present in both saponins, while the delta 171 at C-28 (carboxy group) corresponding to the deacylated saponin, was only detected in the QuilA preparation, indicating 50% of hydrolysis of the ester moiety, probably due to the storage in aqueous solution. The normoterpen moiety was present in both saponins (signals at delta 14-18). The chemical removal of saponin glicidic moieties gave rise to their sapogenin fractions. Their 1H NMR spectra showed the presence of two signals (delta 9.226 and 9.236) for sapogenin R and two signals (delta 9.338 and 9.352) for the QuilA sapogenin. The intensity of the signals suggested two conformational isomers of sapogenin R in the ratio 53% of equatorial aldehyde group to 47% of axial aldehyde group, and two conformational isomers of QuilA sapogenin in the ratio 76% of equatorial aldehyde group to 24% of axial aldehyde group. The chemical treatment abolished the saponin slight in vivo toxicity, reduced their hemolytic potential, did not affect their aldehyde contents, but gave rise to an enriched axial aldehyde-containing sapogenin R with enhanced potential on antibody humoral response (anti-IgM, IgG, IgG1, IgG2a, IgG2b and IgG3) and to an enriched equatorial aldehyde-containing QuilA-sapogenin that induced a mainly cellular specific immune response (increased intradermal response to leishmanial antigen and IFNgamma sera levels) and effective protection against murine infection by L. donovani (77% reduction in liver parasitic load). Our results suggest that the Riedel de Haen saponin is probably a Quillaja saponaria saponin.

  11. Synthesis and SAR Study of Novel Peptide Aldehydes as Inhibitors of 20S Proteasome

    Directory of Open Access Journals (Sweden)

    Lihe Zhang

    2011-09-01

    Full Text Available Based on the analysis of the crystal structure of MG101 (1 and 20S proteasomes, a new series of peptide aldehyde derivatives were designed and synthesized. Their ability to inhibit 20S proteasome was assayed. Among them, Cbz-Glu(OtBu-Phe-Leucinal (3c, Cbz-Glu(OtBu-Leu-Leucinal (3d, and Boc-Ser(OBzl-Leu-Leucinal (3o exhibited the most activity, which represented an order of magnitude enhancement compared with MG132 (2. The covalent docking protocol was used to explore the binding mode. The structure-activity relationship of the peptide aldehyde inhibitors is discussed.

  12. ATOMIC-STRUCTURE OF THE CUBIC CORE OF THE PYRUVATE-DEHYDROGENASE MULTIENZYME COMPLEX

    NARCIS (Netherlands)

    MATTEVI, A; OBMOLOVA, G; SCHULZE, E; KALK, KH; WESTPHAL, AH; DEKOK, A; HOL, WGJ

    1992-01-01

    The highly symmetric pyruvate dehydrogenase multienzyme complexes have molecular masses ranging from 5 to 10 million daltons. They consist of numerous copies of three different enzymes: pyruvate dehydrogenase, dihydrolipoyl transacetylase, and lipoamide dehydrogenase. The three-dimensional crystal

  13. Enzymatic urea adaptation: lactate and malate dehydrogenase in elasmobranchs

    Czech Academy of Sciences Publication Activity Database

    Lagana, G.; Bellocco, E.; Mannucci, C.; Leuzzi, U.; Tellone, E.; Kotyk, Arnošt; Galtieri, A.

    2006-01-01

    Roč. 55, č. 6 (2006), s. 675-688 ISSN 0862-8408 Institutional research plan: CEZ:AV0Z50110509 Keywords : elasmobranchs * lactate dehydrogenase * malate dehydrogenase Subject RIV: CE - Biochemistry Impact factor: 2.093, year: 2006

  14. Cloning and expression analysis of alcohol dehydrogenase ( Adh ...

    African Journals Online (AJOL)

    Hybrid promoters are created by shuffling of DNA fragments while keeping intact regulatory regions crucial of promoter activity. Two fragments of alcohol dehydrogenase (Adh) promoter from Zea mays were selected to generate hybrid promoter. Sequence analysis of both alcohol dehydrogenase promoter fragments through ...

  15. Study on the triphenyl tetrazolium chloride– dehydrogenase activity ...

    African Journals Online (AJOL)

    A quick analysis of the sludge activity method based on triphenyltetrazolium chloride-dehydrogenase activity (TTC-DHA) was developed to change the rule and status of the biological activity of the activated sludge in tomato paste wastewater treatment. The results indicate that dehydrogenase activity (DHA) can effectively ...

  16. Some Properties of Glutamate Dehydrogenase from the Marine Red ...

    African Journals Online (AJOL)

    Keywords: ammonia assimilation, glutamate dehydrogenase, GDH, Gracilaria sordida, red alga, enzyme activity. Glutamate dehydrogenases (GDH, EC ... Anabolic functions could be assimilation of ammonia released during photorespiration and synthesis of N-rich transport compounds. Western Indian Ocean Journal of ...

  17. Kinetics of forming aldehydes in frying oils and their distribution in French fries revealed by LC-MS-based chemometrics

    Science.gov (United States)

    Aldehydes are major secondary lipid oxidation products (LOPs) from heating vegetable oils and deep frying. The routes and reactions that generate aldehydes have been extensively investigated, but the sequences and kinetics of their formation in oils are poorly defined. In this study, a platform comb...

  18. Aldehyde-Selective Wacker-Type Oxidation of Unbiased Alkenes Enabled by a Nitrite Co-Catalyst

    KAUST Repository

    Wickens, Zachary K.

    2013-09-13

    Breaking the rules: Reversal of the high Markovnikov selectivity of Wacker-type oxidations was accomplished using a nitrite co-catalyst. Unbiased aliphatic alkenes can be oxidized with high yield and aldehyde selectivity, and several functional groups are tolerated. 18O-labeling experiments indicate that the aldehydic O atom is derived from the nitrite salt.

  19. INFLUENCE OF SELECTED PHARMACEUTICALS ON ACTIVATED SLUDGE DEHYDROGENASE ACTIVITY

    Directory of Open Access Journals (Sweden)

    Agnieszka Tomska

    2016-06-01

    The aim of this work was to evaluate the effect of selected antibiotics - sulfanilamide and erythromycin on activated sludge dehydrogenase activity with use of trifenyltetrazolinum chloride (TTC test. Dehydrogenases activity is an indicator of biochemical activity of microorganisms present in activated sludge or the ability to degrade organic compounds in waste water. TTC test is particularly useful for the regularity of the course of treatment, in which the presence of inhibitors of biochemical reactions and toxic compounds are present. It was observed that the dehydrogenase activity decreases with the increase of a antibiotics concentration. The lowest value of the dehydrogenase activity equal to 32.4 μmol TF / gMLSS obtained at sulfanilamide concentration 150mg / l. For this sample, an inhibition of dehydrogenase activity was 31%.

  20. Effect of selected aldehydes found in the corncob hemicellulose hydrolysate on the growth and xylitol fermentation of Candida tropicalis.

    Science.gov (United States)

    Wang, Le; Tang, Pingwah; Fan, Xiaoguang; Yuan, Qipeng

    2013-01-01

    The effects of four aldehydes (furfural, 5-hydroxymethylfurfural, vanillin and syringaldehyde), which were found in the corncob hemicellulose hydrolysate, on the growth and xylitol fermentation of Candida tropicalis were investigated. The results showed that vanillin was the most toxic aldehyde for the xylitol fermentation, followed by syringaldehyde, furfural and 5-hydroxymethylfurfural. Moreover, the binary combination tests revealed that furfural amplified the toxicity of other aldehydes and the toxicities of other binary combinations without furfural were simply additive. Based on the fermentation experiments, it was demonstrated that the inhibition of aldehydes could be alleviated by prolonging the fermentation incubation, increasing the initial cell concentration, enhancing the initial pH value and minimizing the furfural levels in the hydrolysate evaporation process. The strategies that we proposed to suppress the inhibitory effects of the aldehydes successfully avoided the complicated and costly detoxifications. Our findings could be potentially adopted for the industrial xylitol fermentation from hydrolysates. © 2013 American Institute of Chemical Engineers.

  1. Modelling of the partial oxidation of {alpha}, {beta}-unsaturated aldehydes on Mo-V-oxides based catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Boehnke, H.; Petzoldt, J.C.; Stein, B.; Weimer, C.; Gaube, J.W. [Technische Univ. Darmstadt (Germany). Inst. fuer Chemische Technologie

    1998-12-31

    A kinetic model based on the Mars-van Krevelen mechanism that allows to describe the microkinetics of the heterogeneously catalysed partial oxidation of {alpha}, {beta}-unsaturated aldehydes is presented. This conversion is represented by a network, composed of the oxidation of the {alpha}, {beta}-unsaturated aldehyde towards the {alpha}, {beta}-unsaturated carboxylic acid and the consecutive oxidation of the acid as well as the parallel reaction of the aldehyde to products of deeper oxidation. The reaction steps of aldehyde respectively acid oxidation and catalyst reoxidation have been investigated separately in transient experiments. The combination of steady state and transient experiments has led to an improved understanding of the interaction of the catalyst with the aldehyde and the carboxylic acids as well as to a support of the kinetic model assumptions. (orig.)

  2. Enantiocomplementary Yarrowia lipolytica Oxidoreductases: Alcohol Dehydrogenase 2 and Short Chain Dehydrogenase/Reductase

    Directory of Open Access Journals (Sweden)

    Margit Winkler

    2013-08-01

    Full Text Available Enzymes of the non-conventional yeast Yarrowia lipolytica seem to be tailor-made for the conversion of lipophilic substrates. Herein, we cloned and overexpressed the Zn-dependent alcohol dehydrogenase ADH2 from Yarrowia lipolytica in Escherichia coli. The purified enzyme was characterized in vitro. The substrate scope for YlADH2 mediated oxidation and reduction was investigated spectrophotometrically and the enzyme showed a broader substrate range than its homolog from Saccharomyces cerevisiae. A preference for secondary compared to primary alcohols in oxidation direction was observed for YlADH2. 2-Octanone was investigated in reduction mode in detail. Remarkably, YlADH2 displays perfect (S-selectivity and together with a highly (R-selective short chain dehydrogenase/ reductase from Yarrowia lipolytica it is possible to access both enantiomers of 2-octanol in >99% ee with Yarrowia lipolytica oxidoreductases.

  3. Immobilisation and characterisation of biocatalytic co-factor recycling enzymes, glucose dehydrogenase and NADH oxidase, on aldehyde functional ReSynTM polymer microspheres

    CSIR Research Space (South Africa)

    Twala, BV

    2012-03-01

    Full Text Available 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...

  4. Ethanol Disrupts Chondrification of the Neurocranial Cartilages in Medaka Embryos without Affecting Aldehyde Dehydrogenase 1A2 (Aldh1A2) Promoter Methylation

    Science.gov (United States)

    Medaka (Oryzias latipes) embryos at different developmental stages were exposed to ethanol for 48 h, then allowed to hatch. Teratogenic effects were evaluated in hatchlings after examining chondrocranial cartilage deformities. Ethanol disrupted cartilage development in medaka in a dose and developme...

  5. Cofactor Specificity of the Bifunctional Alcohol and Aldehyde Dehydrogenase (AdhE) in Wild-Type and Mutant Clostridium thermocellum and Thermoanaerobacteriumsaccharolyticum

    NARCIS (Netherlands)

    Zheng, T.; Olson, D.G.; Tian, L.; Bomble, Y.J.; Himmel, M.E.; Lo, J.; Hon, S.; Shaw, A.J.; Van Dijken, J.P.; Lynd, L.R.

    2015-01-01

    Clostridium thermocellum and Thermoanaerobacterium saccharolyticum are thermophilic bacteria that have been engineered to produce ethanol from the cellulose and hemicellulose fractions of biomass, respectively. Although engineered strains of T. saccharolyticum produce ethanol with a yield of 90% of

  6. Expression of the Vibrio cholerae gene encoding aldehyde dehydrogenase is under control of ToxR, the cholera toxin transcriptional activator.

    OpenAIRE

    Parsot, C; Mekalanos, J J

    1991-01-01

    The toxR gene of Vibrio cholerae encodes a transcriptional activator required for the expression of the cholera toxin genes (ctxAB) and more than 15 other genes encoding secreted or membrane proteins. The latter group includes virulence genes involved in the biogenesis of the TCP pilus, the accessory colonization factor, and such ToxR-activated genes as tagA, mutations in which cause no detectable virulence defect in the suckling mouse model. To analyze the regulation of expression and the st...

  7. Action of sulphite on plant malate dehydrogenase

    Energy Technology Data Exchange (ETDEWEB)

    Ziegler, I.

    1974-01-01

    SO/sub 3//sup 2 -/ acts on NAD- and NADP-dependent malate dehydrogenase in several ways. Firstly, SO/sub 3//sup 2 -/ favours the appearance of low MW species (65000 and 39000 daltons) in Sephadex gel chromatography. Secondly, the enzyme from which is obtained by gel chromatography with dithioerythritol plus nucleotide cofactor is changed in the presence of SO/sub 3//sup 2 -/. This is indicated by the appearance of a linear reaction (instead of curvilinear), and by the abolition of the biphasic sigmoidal kinetics on varying substrate and cofactor concentrations. Thus the inhibition of initial velocity at high substrate or cofactor concentrations is even more marked than at lower ones. Thirdly, SO/sub 3//sup 2 -/ strongly reduces the activity in substrate saturating conditions.

  8. Variants of glycerol dehydrogenase having D-lactate dehydrogenase activity and uses thereof

    Science.gov (United States)

    Wang, Qingzhao; Shanmugam, Keelnatham T.; Ingram, Lonnie O'Neal

    2017-08-29

    The present invention provides methods of designing and generating glycerol dehydrogenase (GlyDH) variants that have altered function as compared to a parent polypeptide. The present invention further provides nucleic acids encoding GlyDH polypeptide variants having altered function as compared to the parent polypeptide. Host cells comprising polynucleotides encoding GlyDH variants and methods of producing lactic acids are also provided in various aspects of the invention.

  9. Cloning and sequencing of the gene encoding the 72-kilodalton dehydrogenase subunit of alcohol dehydrogenase from Acetobacter aceti.

    Science.gov (United States)

    Inoue, T; Sunagawa, M; Mori, A; Imai, C; Fukuda, M; Takagi, M; Yano, K

    1989-06-01

    A genomic library of Acetobacter aceti DNA was constructed by using a broad-host-range cosmid vector. Complementation of a spontaneous alcohol dehydrogenase-deficient mutant resulted in the isolation of a plasmid designated pAA701. Subcloning and deletion analysis of pAA701 limited the region that complemented the deficiency in alcohol dehydrogenase activity of the mutant. The nucleotide sequence of this region was determined and showed that this region contained the full structural gene for the 72-kilodalton dehydrogenase subunit of the alcohol dehydrogenase enzyme complex. The predicted amino acid sequence of the gene showed homology with sequences of methanol dehydrogenase structural genes of Paracoccus denitrificans and Methylobacterium organophilum.

  10. Catalytic Oxidation of Lignins into the Aromatic Aldehydes: General Process Trends and Development Prospects

    Directory of Open Access Journals (Sweden)

    Valery E. Tarabanko

    2017-11-01

    Full Text Available This review discusses principal patterns that govern the processes of lignins’ catalytic oxidation into vanillin (3-methoxy-4-hydroxybenzaldehyde and syringaldehyde (3,5-dimethoxy-4-hydroxybenzaldehyde. It examines the influence of lignin and oxidant nature, temperature, mass transfer, and of other factors on the yield of the aldehydes and the process selectivity. The review reveals that properly organized processes of catalytic oxidation of various lignins are only insignificantly (10–15% inferior to oxidation by nitrobenzene in terms of yield and selectivity in vanillin and syringaldehyde. Very high consumption of oxygen (and consequentially, of alkali in the process—over 10 mol per mol of obtained vanillin—is highlighted as an unresolved and unexplored problem: scientific literature reveals almost no studies devoted to the possibilities of decreasing the consumption of oxygen and alkali. Different hypotheses about the mechanism of lignin oxidation into the aromatic aldehydes are discussed, and the mechanism comprising the steps of single-electron oxidation of phenolate anions, and ending with retroaldol reaction of a substituted coniferyl aldehyde was pointed out as the most convincing one. The possibility and development prospects of single-stage oxidative processing of wood into the aromatic aldehydes and cellulose are analyzed.

  11. Substituent effect of phenolic aldehyde inhibition on alcoholic fermentation by Saccharomyces cerevisiae

    Science.gov (United States)

    Rui Xie; Maobing Tu; Thomas Elder

    2016-01-01

    Phenolic compounds significantly inhibit microbial fermentation of biomass hydrolysates. To understand thequantitative structure-inhibition relationship of phenolic aldehydes on alcoholic fermentation, the effect of 11 differentsubstituted benzaldehydes on the final ethanol yield was examined. The results showed that the degree of phenolic...

  12. Sorption kinetics for the removal of aldehydes from aqueous streams with extractant impregnated resins

    NARCIS (Netherlands)

    Babic, K.; van der Ham, Aloysius G.J.; de Haan, A.B.

    2008-01-01

    The sorption kinetics for the removal aldehydes from aqueous solutions with Amberlite XAD-16 and MPP particles impregnated with Primene JM-T was investigated. A model, accounting for the simultaneous mass transfer and chemical reaction, is developed to describe the process. It is based on the

  13. A Highly Efficient Solvent-Free Acetalization of Aldehydes to 1,1 ...

    African Journals Online (AJOL)

    NICO

    1,1-Diacetates, sulfonic acid functionalized silica, acetalization, solvent-free reaction, SiO2-Pr-SO3H. 1. Introduction. Protection of aldehydes is a frequently used and important method in organic chemistry. Many procedures have been developed for this aim. For the acetalization of carbonyl groups, acetic anhydride can be ...

  14. Efficient Method for Aromatic-Aldehyde Oxidation by Cleavage of Their Hydrazones Catalysed by Trimethylsilanolate

    Czech Academy of Sciences Publication Activity Database

    Bürglová, K.; Okorochenkov, S.; Buděšínský, Miloš; Hlaváč, J.

    2017-01-01

    Roč. 2017, č. 2 (2017), s. 389-396 ISSN 1434-193X R&D Projects: GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : aldehydes * oxidation * hydrazones * solid-phase synthesis * reaction mechanisms Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 2.834, year: 2016

  15. A Highly Efficient Solvent-Free Acetalization of Aldehydes to 1,1 ...

    African Journals Online (AJOL)

    1,1-Diacetates are prepared in excellent yields from aldehydes and acetic anhydride under solvent-free conditions at room temperature in short reaction times using catalytic amount of sulfonic acid functionalized silica (SiO2-Pr-SO3H) which could be easily handled and removed from the mixture of reaction. Keywords: 1 ...

  16. Reduction of Aldehydes and Ketones to Corresponding Alcohols Using Diammonium Hydrogen Phosphite and Commercial Zinc Dust

    Directory of Open Access Journals (Sweden)

    K. Anil Kumar

    2011-01-01

    Full Text Available A mild and an efficient system has been developed for the reduction of aromatic aldehydes and ketones to their corresponding alcohols in good yield using inexpensive commercial zinc dust as catalyst and diammonium hydrogen phosphite as a hydrogen donor.

  17. Critical role of aldehydes in cigarette smoke-induced acute airway inflammation

    NARCIS (Netherlands)

    van der Toorn, Marco; Slebos, Dirk-Jan; de Bruin, Harold G.; Gras, Renee; Rezayat, Delaram; Jorge, Lucie; Sandra, Koen; van Oosterhout, Antoon J. M.

    2013-01-01

    Background: Cigarette smoking (CS) is the most important risk factor for COPD, which is associated with neutrophilic airway inflammation. We hypothesize, that highly reactive aldehydes are critical for CS-induced neutrophilic airway inflammation. Methods: BALB/c mice were exposed to CS, water

  18. Ambient concentrations of aldehydes in relation to Beijing Olympic air pollution control measures

    Science.gov (United States)

    Gong, J. C.; Zhu, T.; Hu, M.; Zhang, L. W.; Cheng, H.; Zhang, L.; Tong, J.; Zhang, J.

    2010-08-01

    Aldehydes are ubiquitous constituents of the atmosphere. Their concentrations are elevated in polluted urban atmospheres. The present study was carried out to characterize three aldehydes of most health concern (formaldehyde, acetaldehyde, and acrolein) in a central Beijing site in the summer and early fall of 2008 (from June to October). Measurements were made before, during, and after the Beijing Olympics to examine whether the air pollution control measures implemented to improve Beijing's air quality during the Olympics had any impact on concentrations of the three aldehydes. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.34 ± 15.12 μg/m3, 27.09 ± 15.74 μg/m3 and 2.32 ± 0.95 μg/m3, respectively, for the entire period of measurements, all being the highest among the levels measured in cities around the world in photochemical smog seasons. Among the three measured aldehydes, only acetaldehyde had a substantially reduced mean concentration during the Olympic air pollution control period compared to the pre-Olympic period. Formaldehyde and acrolein followed the changing pattern of temperature and were each significantly correlated with ozone (a secondary product of photochemical reactions). In contrast, acetaldehyde was significantly correlated with several pollutants emitted mainly from local emission sources (e.g., NO2, CO, and PM2.5). These findings suggest that local direct emissions had a larger impact on acetaldehyde than formaldehyde and acrolein.

  19. The molecular cloning of dihydroartemisinic aldehyde reductase and its implication in artemisinin biosynthesis in Artemisia annua

    NARCIS (Netherlands)

    Ryden, A.M.; Ruyter-Spira, C.P.; Quax, W.J.; Hiroyuki, O.; Toshiya, M.; Kayser, O.; Bouwmeester, H.J.

    2010-01-01

    A key point in the biosynthesis of the antimalarial drug artemisinin is the formation of dihydroartemisinic aldehyde which represents the key difference between chemotype specific pathways. This key intermediate is the substrate for several competing enzymes, some of which increase the metabolic

  20. Formation of Aldehyde and Ketone Compounds during Production and Storage of Milk Powder

    Directory of Open Access Journals (Sweden)

    Weijun Wang

    2012-08-01

    Full Text Available Certain aldehyde and ketone compounds can be used as indicators, at a molecular level, of the oxidized flavor of milk powder instead of sensory evaluation. This study investigated the formation of aldehyde and ketone compounds as affected by the heat-related processing and storage of milk powder. The compounds were extracted by solid phase microextraction fiber and determined using gas chromatography-mass spectrometry. In the results, higher contents of hexanal, 2-heptanone, octanal and 3-octen-2-one were detected in concentrated milk and fresh milk powders than in raw milk and heated milk. The levels of these compounds increased with increasing time of storage of milk powder. Meanwhile, the DPPH radical scavenging activity decreased and peroxide value increased during the production and storage of milk powder. In addition, the pore volume distribution of milk powder particle was determined by nitrogen isotherm adsorption. The porosity of milk powder was significantly correlated to the changes of aldehyde and ketone compounds during storages periods of 3 months (r > 0.689, p < 0.05 and 6 months (r > 0.806, p < 0.01. Therefore attention should be paid to the detectable aldehyde and ketone molecules to control the oxidized flavor, which was influenced by pre-heating as well as concentration and drying during milk powder production.

  1. Catalytic asymmetric allylation of aliphatic aldehydes by chiral bipyridine N,N'-dioxides

    Czech Academy of Sciences Publication Activity Database

    Hrdina, R.; Boyd, T.; Valterová, Irena; Hodačová, Jana; Kotora, Martin

    -, č. 20 (2008), s. 3141-3144 ISSN 0936-5214 Grant - others:GA MŠk(CZ) LC06070 Program:LC Institutional research plan: CEZ:AV0Z40550506 Keywords : allylations * aldehydes * Lewis base * asymmetric catalysis * solvent effect Subject RIV: CC - Organic Chemistry Impact factor: 2.659, year: 2008

  2. Supported Rh-phosphine complex catalysts for continuous gas-phase decarbonylation of aldehydes

    DEFF Research Database (Denmark)

    Malcho, Phillip; Garcia-Suarez, Eduardo J.; Mentzel, Uffe Vie

    2014-01-01

    Heterogeneous silica supported rhodium-phosphine complex catalysts are employed for the first time in the catalytic decarbonylation of aldehydes in continuous gas-phase. The reaction protocol is exemplified for the decarbonylation of p-tolualdehyde to toluene and further extended to other aromati...

  3. Chronic oral exposure to the aldehyde pollutant acrolein induces dilated cardiomyopathy

    Science.gov (United States)

    Ismahil, Mohamed Ameen; Hamid, Tariq; Haberzettl, Petra; Gu, Yan; Chandrasekar, Bysani; Srivastava, Sanjay; Bhatnagar, Aruni

    2011-01-01

    Environmental triggers of dilated cardiomyopathy are poorly understood. Acute exposure to acrolein, a ubiquitous aldehyde pollutant, impairs cardiac function and cardioprotective responses in mice. Here, we tested the hypothesis that chronic oral exposure to acrolein induces inflammation and cardiomyopathy. C57BL/6 mice were gavage-fed acrolein (1 mg/kg) or water (vehicle) daily for 48 days. The dose was chosen based on estimates of human daily unsaturated aldehyde consumption. Compared with vehicle-fed mice, acrolein-fed mice exhibited significant (P acrolein adduct formation indicative of physical translocation of ingested acrolein to the heart. Acrolein also induced myocyte hypertrophy (∼2.2-fold increased myocyte area, P acrolein-exposed hearts, along with upregulated gene expression of proinflammatory cytokines tumor necrosis factor-α and interleukin-1β. Long-term oral exposure to acrolein, at an amount within the range of human unsaturated aldehyde intake, induces a phenotype of dilated cardiomyopathy in the mouse. Human exposure to acrolein may have analogous effects and raise consideration of an environmental, aldehyde-mediated basis for heart failure. PMID:21908791

  4. Solvent-free oxidation of aldehydes to acids by TBHP using ...

    Indian Academy of Sciences (India)

    chromic acid, potassium permanganate in acidic, basic and neutral solution, bromine and nitric acid are not suitable for the large scale preparation of carboxylic acid because of the formation of hazardous waste. Balicki Roman3 achieved mild oxidation of aromatic and heteroaromatic aldehydes to the corresponding.

  5. Syntheses of a Flobufen Metabolite and Dapoxetine Based on Enantioselective Allylation of Aromatic Aldehydes

    Czech Academy of Sciences Publication Activity Database

    Hessler, F.; Korotvička, A.; Nečas, D.; Valterová, Irena; Kotora, M.

    2014-01-01

    Roč. 2014, č. 12 (2014), s. 2543-2548 ISSN 1434-193X Grant - others:GA ČR(CZ) GAP207/11/0587 Institutional support: RVO:61388963 Keywords : synthetic methods * asymmetric catalysis * organocatalysis * allylation * aldehydes * enantioselectivity Subject RIV: CC - Organic Chemistry Impact factor: 3.065, year: 2014

  6. An Alumino-Mannich Reaction of Organoaluminum Reagents, Silylated Amines, and Aldehydes.

    Science.gov (United States)

    Tarasewicz, Anika; Ensan, Deeba; Batey, Robert A

    2018-03-08

    A multi-component coupling using organoaluminum reagents, silylated amines, and aldehydes results in the formation of tertiary amines. Both alkenyl- and alkylaluminum reagents undergo reaction with iminium ion substrates for which the corresponding Petasis borono-Mannich reactions are unsuccessful. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. The Molecular Cloning of Dihydroartemisinic Aldehyde Reductase and its Implication in Artemisinin Biosynthesis in Artemisia annua

    NARCIS (Netherlands)

    Ryden, Anna-Margareta; Ruyter-Spira, Carolien; Quax, Wim J.; Osada, Hiroyuki; Muranaka, Toshiya; Kayser, Oliver; Bouwmeester, Harro

    2010-01-01

    A key point in the biosynthesis of the antimalarial drug artemisinin is the formation of dihydroartemisinic aldehyde which represents the key difference between chemotype specific pathways. This key intermediate is the substrate for several competing enzymes, some of which increase the metabolic

  8. Aldehyde-functionalized porous nanocellulose for effective removal of heavy metal ions from aqueous solutions

    Science.gov (United States)

    C. Yao; F. Wang; Z. Cai; X. Wang

    2016-01-01

    Nanoscale sorption is a promising strategy for catalyst and purification system design. In this paper, cellulose nanofibrils (CNFs) were densely attached with aldehyde functional groups on the surface via a mild periodate oxidation process, and then applied as mesoporous sorbents to remove Cu(II) and Pb(II) from aqueous solutions. In the studied concentration range (0....

  9. Substrate-Controlled Diastereoselectivity Reversal in NHC-Catalyzed Cross-Benzoin Reactions Using N-Boc-N-Bn-Protected α-Amino Aldehydes.

    Science.gov (United States)

    Haghshenas, Pouyan; Quail, J Wilson; Gravel, Michel

    2016-12-16

    The effectiveness of utilizing N-Bn-N-Boc-α-amino aldehydes in cross-benzoin reactions with heteroaromatic aldehydes is demonstrated. The reaction is both chemoselective and syn-selective, making it complementary to the anti-selective cross-benzoin reaction of NHBoc-α-amino aldehydes. Good diastereoselectivity is obtained for a variety of amino aldehydes, including nonhindered ones. A Felkin-Anh model can be used to rationalize the observed diastereoselectivity.

  10. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    Directory of Open Access Journals (Sweden)

    P. O. Wennberg

    2010-08-01

    Full Text Available Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene, the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA via methacrolein (a C4-unsaturated aldehyde under urban high-NOx conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN as the important intermediate to isoprene and methacrolein SOA in this NOx regime. Here we show that as a result of this chemistry, NO2 enhances SOA formation from methacrolein and two other α, β-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NOx effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are α, β-unsaturated and contain an additional methyl group on the α-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232 is insignificant, even under high-NO2 conditions, as PAN (peroxy acyl nitrate, RC(OOONO2 formation is structurally unfavorable. At atmospherically relevant NO2/NO ratios (3–8, the SOA yields from isoprene high-NOx photooxidation are 3 times greater than previously measured at lower NO2/NO ratios. At sufficiently high NO2 concentrations, in systems of α, β-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO2 can exceed that from RO2+HO2 reactions under the same inorganic seed conditions, making RO2+NO2 an important channel for SOA formation.

  11. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    Science.gov (United States)

    Chan, A. W. H.; Chan, M. N.; Surratt, J. D.; Chhabra, P. S.; Loza, C. L.; Crounse, J. D.; Yee, L. D.; Flagan, R. C.; Wennberg, P. O.; Seinfeld, J. H.

    2010-08-01

    Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene), the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA) via methacrolein (a C4-unsaturated aldehyde) under urban high-NOx conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN) as the important intermediate to isoprene and methacrolein SOA in this NOx regime. Here we show that as a result of this chemistry, NO2 enhances SOA formation from methacrolein and two other α, β-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NOx effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are α, β-unsaturated and contain an additional methyl group on the α-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232) is insignificant, even under high-NO2 conditions, as PAN (peroxy acyl nitrate, RC(O)OONO2) formation is structurally unfavorable. At atmospherically relevant NO2/NO ratios (3-8), the SOA yields from isoprene high-NOx photooxidation are 3 times greater than previously measured at lower NO2/NO ratios. At sufficiently high NO2 concentrations, in systems of α, β-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO2 can exceed that from RO2+HO2 reactions under the same inorganic seed conditions, making RO2+NO2 an important channel for SOA formation.

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

    International Nuclear Information System (INIS)

    Kaspera, Rüdiger; Sahele, Tariku; Lakatos, Kyle; Totah, Rheem A.

    2012-01-01

    Highlights: ► Cytochrome P450BM-3 reduced aldehydes to alcohols efficiently (k cat ∼ 25 min −1 ). ► Reduction is a direct hydride transfer from R-NADP 2 H to the carbonyl moiety. ► P450 domain variants enhance reduction through potential allosteric/redox interactions. ► Novel reaction will have implications for metabolism of xenobiotics. -- Abstract: Cytochrome P450BM-3 catalyzed the reduction of lipophilic aldehydes to alcohols efficiently. A k cat of ∼25 min −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. The reduction was caused by a direct hydride transfer from preferentially R-NADP 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 2 H but not D 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kaspera, Ruediger; Sahele, Tariku; Lakatos, Kyle [Department of Medicinal Chemistry, University of Washington, Box 357610, Seattle, WA 98195-7610 (United States); Totah, Rheem A., E-mail: rtotah@u.washington.edu [Department of Medicinal Chemistry, University of Washington, Box 357610, Seattle, WA 98195-7610 (United States)

    2012-02-17

    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. The 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.

  14. Occupational exposure of aldehydes resulting from the storage of wood pellets.

    Science.gov (United States)

    Rahman, Mohammad Arifur; Rossner, Alan; Hopke, Philip K

    2017-06-01

    An exposure assessment was conducted to investigate the potential for harmful concentrations of airborne short chain aldehydes emitted from recently stored wood pellets. Wood pellets can emit a number of airborne aldehydes include acetaldehyde, formaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and hexanal. Exposure limits have been set for these compounds since they can result in significant irritation of the upper respiratory system at elevated concentrations. Formaldehyde is a recognized human carcinogen and acetaldehyde is an animal carcinogen. Thus, air sampling was performed in a wood pellet warehouse at a pellet mill, two residential homes with bulk wood pellet storage bins, and in controlled laboratory experiments to evaluate the risk to occupants. Using NIOSH method 2539, sampling was conducted in five locations in the warehouse from April-June 2016 when it contained varying quantities of bagged pellets as well as two homes with ten ton bulk storage bins. The aldehyde concentrations were found to increase with the amount of stored pellets. Airborne concentrations of formaldehyde were as high as 0.45 ppm in the warehouse exceeding the NIOSH REL-C, and ACGIH TLV-C occupational exposure limits (OELs). The concentrations of aldehydes measured in the residential bins were also elevated indicating emissions may raise indoor air quality concerns for occupants. While individual exposures are of concern the combined irritant effect of all the aldehydes is a further raise the concerns for building occupants. To minimize exposure and the risk of adverse health effects to a building's occupants in storage areas with large quantities of pellets, adequate ventilation must be designed into storage areas.

  15. Role of aldehydes in the toxic and mutagenic effects of nitrosamines.

    Science.gov (United States)

    Peterson, Lisa A; Urban, Anna M; Vu, Choua C; Cummings, Meredith E; Brown, Lee C; Warmka, Janel K; Li, Li; Wattenberg, Elizabeth V; Patel, Yesha; Stram, Daniel O; Pegg, Anthony E

    2013-10-21

    α-Hydroxynitrosamine metabolites of nitrosamines decompose to a reactive diazohydroxide and an aldehyde. To test the hypothesis that the aldehydes contribute to the harmful effects of nitrosamines, the toxic and mutagenic activities of three model methylating agents were compared in Chinese hamster ovary cells expressing or not expressing human O⁶-alkylguanine DNA alkyltransferase (AGT). N-Nitrosomethylurethane (NMUr), acetoxymethylmethylnitrosamine (AMMN), and 4-(methylnitrosamino)-4-acetoxy-1-(3-pyridyl)-1-butanone (NNK-4-OAc) are all activated by ester hydrolysis to methanediazohydroxide. NMUr does not form an aldehyde, whereas AMMN generates formaldehyde, and NNK-4-OAc produces 4-oxo-1-(3-pyridyl)-1-butanone (OPB). Since these compounds were likely to alkylate DNA to different extents, the toxic and mutagenic activities of these compounds were normalized to the levels of the most cytotoxic and mutagenic DNA adduct, O⁶-mG, to assess if the aldehydes contributed to the toxicological properties of these methylating agents. Levels of 7-mG indicated that the differences in cytotoxic and mutagenic effects of these compounds resulted from differences in their ability to methylate DNA. When normalized against the levels of O⁶-mG, there was no difference between these three compounds in cells that lacked AGT. However, AMMN and NNK-4-OAc were more toxic than NMUr in cells expressing AGT when normalized against O⁶-mG levels. In addition, AMMN was more mutagenic than NNK-4-OAc and MNUr in these cells. These findings demonstrate that the aldehyde decomposition products of nitrosamines can contribute to the cytotoxic and/or mutagenic activity of methylating nitrosamines.

  16. Aldehyde modification and alum coadjuvancy enhance anti-TNF-α autovaccination and mitigate arthritis in rat.

    Science.gov (United States)

    Bavoso, Alfonso; Ostuni, Angela; De Vendel, Jolanda; Bracalello, Angelo; Shcheglova, Tatiana; Makker, Sudesh; Tramontano, Alfonso

    2015-05-01

    Experimental vaccination to induce antibodies (Abs) capable of cytokine antagonism shows promise as a novel immunotherapy for chronic inflammatory disease. We prepared a hybrid antigen consisting of residues 141-235 of rat TNF-α fused to the C-terminus of glutathione-S-transferase (GST), chemically modified to incorporate aldehyde residues, for development of an auto-vaccine eliciting anti-rTNF-α Abs. In rat immunization the soluble aldehyde-modified fusion protein did not generate observable Ab responses. By contrast, vaccination with the aldehyde-modified fusion protein adsorbed on alum induced anti-TNF-α autoAbs with high titer and neutralizing activity. Induction of adjuvant arthritis in rats pre-immunized with unmodified fusion protein or a control protein in alum resulted in severe inflammation and joint damage, whereas the disease induced in rats immunized with the aldehyde-bearing fusion protein in alum was markedly attenuated. Similar results were obtained in a collagen-induced rat arthritis model. Anti-collagen II IgG Ab titers did not deviate significantly in groups pre-immunized with modified fusion protein and control protein, suggesting that anti-TNF vaccination did not skew the immune response related to disease induction. This study demonstrates synergy between particulate alum and protein bound carbonyl residues for enhancement of protein immunogenicity. The antigen-specific co-adjuvant system could prove advantageous for breaking tolerance in emerging auto-vaccination therapies targeting inflammatory cytokines as well as for enhancing a broader category of subunit vaccines. Aldehyde adduction introduces a minimal modification which, together with the established use of alum as a safe adjuvant for human use, could be favorable for further vaccine development. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

  17. External NAD(P)H dehydrogenases in Acanthamoeba castellanii mitochondria.

    Science.gov (United States)

    Antos-Krzeminska, Nina; Jarmuszkiewicz, Wieslawa

    2014-09-01

    The mitochondrial respiratory chain of plants and some fungi contains multiple rotenone-insensitive NAD(P)H dehydrogenases, of which at least two are located on the outer surface of the inner membrane (i.e., external NADH and external NADPH dehydrogenases). Annotated sequences of the putative alternative NAD(P)H dehydrogenases of the protozoan Acanthamoeba castellanii demonstrated similarity to plant and fungal sequences. We also studied activity of these dehydrogenases in isolated A. castellanii mitochondria. External NADPH oxidation was observed for the first time in protist mitochondria. The coupling parameters were similar for external NADH oxidation and external NADPH oxidation, indicating similar efficiencies of ATP synthesis. Both external NADH oxidation and external NADPH oxidation had an optimal pH of 6.8 independent of relevant ubiquinol-oxidizing pathways, the cytochrome pathway or a GMP-stimulated alternative oxidase. The maximal oxidizing activity with external NADH was almost double that with external NADPH. However, a lower Michaelis constant (K(M)) value for external NADPH oxidation was observed compared to that for external NADH oxidation. Stimulation by Ca(2+) was approximately 10 times higher for external NADPH oxidation, while NADH dehydrogenase(s) appeared to be slightly dependent on Ca(2+). Our results indicate that external NAD(P)H dehydrogenases similar to those in plant and fungal mitochondria function in mitochondria of A. castellanii. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. A Wheat Cinnamyl Alcohol Dehydrogenase TaCAD12 Contributes to Host Resistance to the Sharp Eyespot Disease

    Science.gov (United States)

    Rong, Wei; Luo, Meiying; Shan, Tianlei; Wei, Xuening; Du, Lipu; Xu, Huijun; Zhang, Zengyan

    2016-01-01

    Sharp eyespot, caused mainly by the necrotrophic fungus Rhizoctonia cerealis, is a destructive disease in hexaploid wheat (Triticum aestivum L.). In Arabidopsis, certain cinnamyl alcohol dehydrogenases (CADs) have been implicated in monolignol biosynthesis and in defense response to bacterial pathogen infection. However, little is known about CADs in wheat defense responses to necrotrophic or soil-borne pathogens. In this study, we isolate a wheat CAD gene TaCAD12 in response to R. cerealis infection through microarray-based comparative transcriptomics, and study the enzyme activity and defense role of TaCAD12 in wheat. The transcriptional levels of TaCAD12 in sharp eyespot-resistant wheat lines were significantly higher compared with those in susceptible wheat lines. The sequence and phylogenetic analyses revealed that TaCAD12 belongs to IV group in CAD family. The biochemical assay proved that TaCAD12 protein is an authentic CAD enzyme and possesses catalytic efficiencies toward both coniferyl aldehyde and sinapyl aldehyde. Knock-down of TaCAD12 transcript significantly repressed resistance of the gene-silenced wheat plants to sharp eyespot caused by R. cerealis, whereas TaCAD12 overexpression markedly enhanced resistance of the transgenic wheat lines to sharp eyespot. Furthermore, certain defense genes (Defensin, PR10, PR17c, and Chitinase1) and monolignol biosynthesis-related genes (TaCAD1, TaCCR, and TaCOMT1) were up-regulated in the TaCAD12-overexpressing wheat plants but down-regulated in TaCAD12-silencing plants. These results suggest that TaCAD12 positively contributes to resistance against sharp eyespot through regulation of the expression of certain defense genes and monolignol biosynthesis-related genes in wheat. PMID:27899932

  19. A wheat cinnamyl alcohol dehydrogenase TaCAD12 contributes to host resistance to the sharp eyespot disease

    Directory of Open Access Journals (Sweden)

    Wei Rong

    2016-11-01

    Full Text Available Sharp eyespot, caused mainly by the necrotrophic fungus Rhizoctonia cerealis, is a destructive disease in hexaploid wheat (Triticum aestivum L.. In Arabidopsis, certain cinnamyl alcohol dehydrogenases (CADs have been implicated in monolignol biosynthesis and in defense response to bacterial pathogen infection. However, little is known about CADs in wheat defense responses to necrotrophic or soil-borne pathogens. In this study, we isolate a wheat CAD gene TaCAD12 in response to R. cerealis infection through microarray-based comparative transcriptomics, and study the enzyme activity and defense role of TaCAD12 in wheat. The transcriptional levels of TaCAD12 in sharp eyespot-resistant wheat lines were significantly higher compared with those in susceptible wheat lines. The sequence and phylogenetic analyses revealed that TaCAD12 belongs to IV group in CAD family. The biochemical assay proved that TaCAD12 protein is an authentic CAD enzyme and possesses catalytic efficiencies towards both coniferyl aldehyde and sinapyl aldehyde. Knock-down of TaCAD12 transcript significantly repressed resistance of the gene-silenced wheat plants to sharp eyespot caused by R. cerealis, whereas TaCAD12 overexpression markedly enhanced resistance of the transgenic wheat lines to sharp eyespot. Furthermore, certain defense genes (Defensin, PR10, PR17c, and Chitinase1 and monolignol biosynthesis-related genes (TaCAD1, TaCCR, and TaCOMT1 were up-regulated in the TaCAD12-overexpressing wheat plants but down-regulated in TaCAD12-silencing plants. These results suggest that TaCAD12 positively contributes to resistance against sharp eyespot through regulation of the expression of certain defense genes and monolignol biosynthesis-related genes in wheat.

  20. A Wheat Cinnamyl Alcohol Dehydrogenase TaCAD12 Contributes to Host Resistance to the Sharp Eyespot Disease.

    Science.gov (United States)

    Rong, Wei; Luo, Meiying; Shan, Tianlei; Wei, Xuening; Du, Lipu; Xu, Huijun; Zhang, Zengyan

    2016-01-01

    Sharp eyespot, caused mainly by the necrotrophic fungus Rhizoctonia cerealis , is a destructive disease in hexaploid wheat ( Triticum aestivum L.). In Arabidopsis , certain cinnamyl alcohol dehydrogenases (CADs) have been implicated in monolignol biosynthesis and in defense response to bacterial pathogen infection. However, little is known about CADs in wheat defense responses to necrotrophic or soil-borne pathogens. In this study, we isolate a wheat CAD gene TaCAD12 in response to R. cerealis infection through microarray-based comparative transcriptomics, and study the enzyme activity and defense role of TaCAD12 in wheat. The transcriptional levels of TaCAD12 in sharp eyespot-resistant wheat lines were significantly higher compared with those in susceptible wheat lines. The sequence and phylogenetic analyses revealed that TaCAD12 belongs to IV group in CAD family. The biochemical assay proved that TaCAD12 protein is an authentic CAD enzyme and possesses catalytic efficiencies toward both coniferyl aldehyde and sinapyl aldehyde. Knock-down of TaCAD12 transcript significantly repressed resistance of the gene-silenced wheat plants to sharp eyespot caused by R. cerealis , whereas TaCAD12 overexpression markedly enhanced resistance of the transgenic wheat lines to sharp eyespot. Furthermore, certain defense genes ( Defensin, PR10, PR17c , and Chitinase1 ) and monolignol biosynthesis-related genes ( TaCAD1, TaCCR , and TaCOMT1 ) were up-regulated in the TaCAD12 -overexpressing wheat plants but down-regulated in TaCAD12 -silencing plants. These results suggest that TaCAD12 positively contributes to resistance against sharp eyespot through regulation of the expression of certain defense genes and monolignol biosynthesis-related genes in wheat.

  1. Kinetics and specificity of guinea pig liver aldehyde oxidase and bovine milk xanthine oxidase towards substituted benzaldehydes.

    Science.gov (United States)

    Panoutsopoulos, Georgios I; Beedham, Christine

    2004-01-01

    Molybdenum-containing enzymes, aldehyde oxidase and xanthine oxidase, are important in the oxidation of N-heterocyclic xenobiotics. However, the role of these enzymes in the oxidation of drug-derived aldehydes has not been established. The present investigation describes the interaction of eleven structurally related benzaldehydes with guinea pig liver aldehyde oxidase and bovine milk xanthine oxidase, since they have similar substrate specificity to human molybdenum hydroxylases. The compounds under test included mono-hydroxy and mono-methoxy benzaldehydes as well as 3,4-dihydroxy-, 3-hydroxy-4-methoxy-, 4-hydroxy-3-methoxy-, and 3,4-dimethoxy-benzaldehydes. In addition, various amines and catechols were tested with the molybdenum hydroxylases as inhibitors of benzaldehyde oxidation. The kinetic constants have shown that hydroxy-, and methoxy-benzaldehydes are excellent substrates for aldehyde oxidase (Km values 5x10(-6) M to 1x10(-5) M) with lower affinities for xanthine oxidase (Km values around 10(-4) M). Therefore, aldehyde oxidase activity may be a significant factor in the oxidation of the aromatic aldehydes generated from amines and alkyl benzenes during drug metabolism. Compounds with a 3-methoxy group showed relatively high Vmax values with aldehyde oxidase, whereas the presence of a 3-hydroxy group resulted in minimal Vmax values or no reaction. In addition, amines acted as weak inhibitors, whereas catechols had a more pronounced inhibitory effect on the aldehyde oxidase activity. It is therefore possible that aldehyde oxidase may be critical in the oxidation of the analogous phenylacetaldehydes derived from dopamine and noradrenaline.

  2. Easy access to aroma active unsaturated γ-lactones by addition of modified titanium homoenolate to aldehydes.

    Science.gov (United States)

    Frerot, Eric; Bagnoud, Alain

    2011-04-27

    The homo-Reformatsky reaction, in which a metal homoenolate of an ester is added to an aldehyde, was adapted to produce γ-lactones from unsaturated, enolizable aldehydes. By use of titanium homoenolate, 11 different γ-lactones were synthesized in one step with moderate to good yields from readily available aldehydes. In particular, this procedure allowed the rapid preparation of a series of C(12) unsaturated γ-lactones differing in the position and configuration of the double bond. These reference compounds will be used to identify previously unknown lactones in butter oil. The chromatographic, spectral, and sensory descriptions of the synthesized lactones are provided.

  3. 21 CFR 866.5560 - Lactic dehydrogenase immunological test system.

    Science.gov (United States)

    2010-04-01

    ... found in a variety of conditions, including megaloblastic anemia (decrease in the number of mature red... conditions known to cause increased lactic dehydrogenase levels. (b) Classification. Class I (general...

  4. Targeting isocitrate dehydrogenase (IDH) in cancer.

    Science.gov (United States)

    Fujii, Takeo; Khawaja, Muhammad Rizwan; DiNardo, Courtney D; Atkins, Johnique T; Janku, Filip

    2016-05-01

    Isocitrate dehydrogenase (IDH) is an essential enzyme for cellular respiration in the tricarboxylic acid (TCA) cycle. Recurrent mutations in IDH1 or IDH2 are prevalent in several cancers including glioma, acute myeloid leukemia (AML), cholangiocarcinoma and chondrosarcoma. The mutated IDH1 and IDH2 proteins have a gain-of-function, neomorphic activity, catalyzing the reduction of α-ketoglutarate (α-KG) to 2-hydroxyglutarate (2-HG) by NADPH. Cancer-associated IDH mutations block normal cellular differentiation and promote tumorigenesis via the abnormal production of the oncometabolite 2-HG. High levels of 2-HG have been shown to inhibit α-KG dependent dioxygenases, including histone and deoxyribonucleic acid (DNA) demethylases, which play a key role in regulating the epigenetic state of cells. Current targeted inhibitors of IDH1 (AG120, IDH305), IDH2 (AG221), and pan-IDH1/2 (AG881) selectively inhibit mutant IDH protein and induce cell differentiation in in vitro and in vivo models. Preliminary results from phase I clinical trials with IDH inhibitors in patients with advanced hematologic malignancies have demonstrated an objective response rate ranging from 31% to 40% with durable responses (>1 year) observed. Furthermore, the IDH inhibitors have demonstrated early signals of activity in solid tumors with IDH mutations, including cholangiocarcinomas and low grade gliomas.

  5. Novel Inhibitors Complexed with Glutamate Dehydrogenase

    Science.gov (United States)

    Li, Ming; Smith, Christopher J.; Walker, Matthew T.; Smith, Thomas J.

    2009-01-01

    Mammalian glutamate dehydrogenase (GDH) is a homohexameric enzyme that catalyzes the reversible oxidative deamination of l-glutamate to 2-oxoglutarate using NAD(P)+ as coenzyme. Unlike its counterparts from other animal kingdoms, mammalian GDH is regulated by a host of ligands. The recently discovered hyperinsulinism/hyperammonemia disorder showed that the loss of allosteric inhibition of GDH by GTP causes excessive secretion of insulin. Subsequent studies demonstrated that wild-type and hyperinsulinemia/hyperammonemia forms of GDH are inhibited by the green tea polyphenols, epigallocatechin gallate and epicatechin gallate. This was followed by high throughput studies that identified more stable inhibitors, including hexachlorophene, GW5074, and bithionol. Shown here are the structures of GDH complexed with these three compounds. Hexachlorophene forms a ring around the internal cavity in GDH through aromatic stacking interactions between the drug and GDH as well as between the drug molecules themselves. In contrast, GW5074 and bithionol both bind as pairs of stacked compounds at hexameric 2-fold axes between the dimers of subunits. The internal core of GDH contracts when the catalytic cleft closes during enzymatic turnover. None of the drugs cause conformational changes in the contact residues, but all bind to key interfaces involved in this contraction process. Therefore, it seems likely that the drugs inhibit enzymatic turnover by inhibiting this transition. Indeed, this expansion/contraction process may play a major role in the inter-subunit communication and allosteric regulation observed in GDH. PMID:19531491

  6. Eucalypt NADP-Dependent Isocitrate Dehydrogenase1

    Science.gov (United States)

    Boiffin, Vincent; Hodges, Michael; Gálvez, Susana; Balestrini, Raffaella; Bonfante, Paola; Gadal, Pierre; Martin, Francis

    1998-01-01

    NADP-dependent isocitrate dehydrogenase (NADP-ICDH) activity is increased in roots of Eucalyptus globulus subsp. bicostata ex Maiden Kirkp. during colonization by the ectomycorrhizal fungus Pisolithus tinctorius Coker and Couch. To investigate the regulation of the enzyme expression, a cDNA (EgIcdh) encoding the NADP-ICDH was isolated from a cDNA library of E. globulus-P. tinctorius ectomycorrhizae. The putative polypeptide sequence of EgIcdh showed a high amino acid similarity with plant NADP-ICDHs. Because the deduced EgICDH protein lacks an amino-terminal targeting sequence and shows highest similarity to plant cytosolic ICDHs, it probably represents a cytoplasmic isoform. RNA analysis showed that the steady-state level of EgIcdh transcripts was enhanced nearly 2-fold in ectomycorrhizal roots compared with nonmycorrhizal roots. Increased accumulation of NADP-ICDH transcripts occurred as early as 2 d after contact and likely led to the observed increased enzyme activity. Indirect immunofluorescence microscopy indicated that NADP-ICDH was preferentially accumulated in the epidermis and stele parenchyma of nonmycorrhizal and ectomycorrhizal lateral roots. The putative role of cytosolic NADP-ICDH in ectomycorrhizae is discussed. PMID:9662536

  7. Temperature-sensitive glutamate dehydrogenase mutants of Salmonella typhimurium.

    OpenAIRE

    Dendinger, S M; Brenchley, J E

    1980-01-01

    Mutants of Salmonella typhimurium defective in glutamate dehydrogenase activity were isolated in parent strains lacking glutamate synthase activity by localizcd mutagenesis or by a general mutagenesis combined with a cycloserine enrichment for glutamate auxotrophs. Two mutants with temperature-sensitive phenotypes had glutamate dehydrogenase activities that were more thermolabile than that of an isogenic control strain. Eight other mutants had less than 10% of the wild-type glutamate dehydrog...

  8. Catalytic activity of bovine glutamate dehydrogenase requires a hexamer structure.

    OpenAIRE

    Bell, E T; Bell, J E

    1984-01-01

    Previous workers have shown that the hexamers of glutamate dehydrogenase are dissociated first into trimers and subsequently into monomers by increasing guanidinium chloride concentrations. In renaturation experiments it is shown that trimers of glutamate dehydrogenase can be reassociated to give the hexamer form of the enzyme, with full regain of activity. Monomeric subunits produced at high guanidinium chloride concentrations cannot be renatured. The trimer form of the enzyme is shown to ha...

  9. Pyruvate dehydrogenase complex and lactate dehydrogenase as targets for therapy of acute liver failure.

    Science.gov (United States)

    Ferriero, Rosa; Nusco, Edoardo; De Cegli, Rossella; Carissimo, Annamaria; Manco, Giuseppe; Brunetti-Pierri, Nicola

    2018-03-23

    Acute liver failure is a rapidly progressive deterioration of hepatic function resulting in high mortality and morbidity. Metabolic enzymes can translocate in the nucleus to regulate histone acetylation and gene expression. Levels and activities of pyruvate dehydrogenase complex (PDHC) and lactate dehydrogenase (LDH) were evaluated in nuclear fractions of livers of mice exposed to various hepatotoxins including CD95-Ab, α-amanitin, and acetaminophen. Whole-genome gene expression profiling by RNA-seq was performed in livers of mice with acute liver failure and analyzed by Gene Ontology Enrichment Analysis. Efficacy of histone acetyltransferase inhibitor garcinol and LDH inhibitor galloflavin at reducing liver damage was evaluated in mice with induced hepatotoxicity. Levels and activities of PDHC and LDH were increased in cytoplasmatic and nuclear fractions of livers of mice with acute liver failure. The increase of nuclear PDHC and LDH was associated with increased concentrations of acetyl-coA and lactate in nuclear fractions, and histone H3 hyper-acetylation. Gene expression in livers of mice with acute liver failure suggested that increased histone H3 acetylation induces the expression of genes related to response to damage. Reduced histone acetylation by the histone acetyltransferase inhibitor garcinol decreased liver damage and improved survival in mice with acute liver failure. Knock-down of PDHC or LDH improved viability in cells exposed to a pro-apoptotic stimulus. Treatment with the LDH inhibitor galloflavin that was also found to inhibit PDHC, reduced hepatic necrosis, apoptosis, and expression of pro-inflammatory cytokines in mice with acute liver failure. Mice treated with galloflavin also showed a dose-response increase in survival. PDHC and LDH translocate to the nucleus and are targets for therapy of acute liver failure. Acute liver failure is a rapidly progressive and life-threatening deterioration of liver function resulting in high mortality and

  10. Kinetic properties of the two alcohol dehydrogenase (ADH) isozymes of the Medfly Ceratitis capitata (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Bonvicini, C.; Malacrida, A.R.; Gasperi, G.

    2000-01-01

    Alcohol dehydrogenase (ADH; alcohol: NAD+ oxidoreductase; EC 1.1.1.1) catalyses the reversible interconversion of a variety of alcohols and their corresponding aldehydes and ketones. Among insects, the ADH gene-enzyme system has been extensively studied in several species of Drosophila (Chambers 1988, Heinstra 1993, Ashburner 1998). The best characterised ADH from a non-drosophilid insect is that of the Medfly, Ceratitis capitata (Wied.), based on data from molecular genetics (Malacrida et al. 1992, Gasperi et al. 1992, Brogna et al. 1999), biochemistry (Gasperi et al. 1994) and population genetics (Gasperi et al. 1992, Gomulski et al. 1998). The primary interest in studying this enzymatic function in the Medfly was that the ADH system has been proposed, on the model of Drosophila, as a useful tool for genetic sexing strategies addressed to the biological control of this pest (Robinson et al. 1988). Moreover, molecular characterisation of Adh in a species like C. capitata, that diverged from the Drosophilidae more than 100 million years ago (Beverley and Wilson 1984), is of interest for studying the evolution of this protein in higher diptera. The principal function of ADH in insect metabolism is to catabolise alcohols generated by microbial fermentation in larval and adult feeding sites; in Drosophila melanogaster Meigen, the presence of an active ADH is responsible for two different phenotypic traits, namely alcohol tolerance and alcohol utilisation (Van Delden 1982, David 1988). The ecological niche of C. capitata is different from that of Drosophila species, the first breeding on ripening fruits, the latter breeding on rotten plant material. Consequently, the physiological role of ADH may have diversified in these dipteran species

  11. An Alcohol Dehydrogenase Gene from Synechocystis sp. Confers Salt Tolerance in Transgenic Tobacco

    Directory of Open Access Journals (Sweden)

    So Young Yi

    2017-11-01

    Full Text Available Synechocystis salt-responsive gene 1 (sysr1 was engineered for expression in higher plants, and gene construction was stably incorporated into tobacco plants. We investigated the role of Sysr1 [a member of the alcohol dehydrogenase (ADH superfamily] by examining the salt tolerance of sysr1-overexpressing (sysr1-OX tobacco plants using quantitative real-time polymerase chain reactions, gas chromatography-mass spectrometry, and bioassays. The sysr1-OX plants exhibited considerably increased ADH activity and tolerance to salt stress conditions. Additionally, the expression levels of several stress-responsive genes were upregulated. Moreover, airborne signals from salt-stressed sysr1-OX plants triggered salinity tolerance in neighboring wild-type (WT plants. Therefore, Sysr1 enhanced the interconversion of aldehydes to alcohols, and this occurrence might affect the quality of green leaf volatiles (GLVs in sysr1-OX plants. Actually, the Z-3-hexenol level was approximately twofold higher in sysr1-OX plants than in WT plants within 1–2 h of wounding. Furthermore, analyses of WT plants treated with vaporized GLVs indicated that Z-3-hexenol was a stronger inducer of stress-related gene expression and salt tolerance than E-2-hexenal. The results of the study suggested that increased C6 alcohol (Z-3-hexenol induced the expression of resistance genes, thereby enhancing salt tolerance of transgenic plants. Our results revealed a role for ADH in salinity stress responses, and the results provided a genetic engineering strategy that could improve the salt tolerance of crops.

  12. The effect of altered lignin composition on mechanical properties of CINNAMYL ALCOHOL DEHYDROGENASE (CAD) deficient poplars.

    Science.gov (United States)

    Özparpucu, Merve; Gierlinger, Notburga; Burgert, Ingo; Van Acker, Rebecca; Vanholme, Ruben; Boerjan, Wout; Pilate, Gilles; Déjardin, Annabelle; Rüggeberg, Markus

    2018-04-01

    CAD-deficient poplars enabled studying the influence of altered lignin composition on mechanical properties. Severe alterations in lignin composition did not influence the mechanical properties. Wood represents a hierarchical fiber-composite material with excellent mechanical properties. Despite its wide use and versatility, its mechanical behavior has not been entirely understood. It has especially been challenging to unravel the mechanical function of the cell wall matrix. Lignin engineering has been a useful tool to increase the knowledge on the mechanical function of lignin as it allows for modifications of lignin content and composition and the subsequent studying of the mechanical properties of these transgenics. Hereby, in most cases, both lignin composition and content are altered and the specific influence of lignin composition has hardly been revealed. Here, we have performed a comprehensive micromechanical, structural, and spectroscopic analysis on xylem strips of transgenic poplar plants, which are downregulated for cinnamyl alcohol dehydrogenase (CAD) by a hairpin-RNA-mediated silencing approach. All parameters were evaluated on the same samples. Raman microscopy revealed that the lignin of the hpCAD poplars was significantly enriched in aldehydes and reduced in the (relative) amount of G-units. FTIR spectra indicated pronounced changes in lignin composition, whereas lignin content was not significantly changed between WT and the hpCAD poplars. Microfibril angles were in the range of 18°-24° and were not significantly different between WT and transgenics. No significant changes were observed in mechanical properties, such as tensile stiffness, ultimate stress, and yield stress. The specific findings on hpCAD poplar allowed studying the specific influence of lignin composition on mechanics. It can be concluded that the changes in lignin composition in hpCAD poplars did not affect the micromechanical tensile properties.

  13. Structural determinants of oligomerization of δ(1)-pyrroline-5-carboxylate dehydrogenase: identification of a hexamerization hot spot.

    Science.gov (United States)

    Luo, Min; Singh, Ranjan K; Tanner, John J

    2013-09-09

    The aldehyde dehydrogenase (ALDH) superfamily member Δ(1)-pyrroline-5-carboxylate dehydrogenase (P5CDH) catalyzes the NAD(+)-dependent oxidation of glutamate semialdehyde to glutamate, which is the final step of proline catabolism. Defects in P5CDH activity lead to the metabolic disorder type II hyperprolinemia, P5CDH is essential for virulence of the fungal pathogen Cryptococcus neoformans, and bacterial P5CDHs have been targeted for vaccine development. Although the enzyme oligomeric state is known to be important for ALDH function, the oligomerization of P5CDH has remained relatively unstudied. Here we determine the oligomeric states and quaternary structures of four bacterial P5CDHs using a combination of small-angle X-ray scattering, X-ray crystallography, and dynamic light scattering. The P5CDHs from Thermus thermophilus and Deinococcus radiodurans form trimer-of-dimers hexamers in solution, which is the first observation of a hexameric ALDH in solution. In contrast, two Bacillus P5CDHs form dimers in solution but do not assemble into a higher-order oligomer. Site-directed mutagenesis was used to identify a hexamerization hot spot that is centered on an arginine residue in the NAD(+)-binding domain. Mutation of this critical Arg residue to Ala in either of the hexameric enzymes prevents hexamer formation in solution. Paradoxically, the dimeric Arg-to-Ala T. thermophilus mutant enzyme packs as a hexamer in the crystal state, which illustrates the challenges associated with predicting the biological assembly in solution from crystal structures. The observation of different oligomeric states among P5CDHs suggests potential differences in cooperativity and protein-protein interactions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Crystal structure and catalytic characterization of the dehydrogenase/reductase SDR family member 4 (DHRS4) from Caenorhabditis elegans.

    Science.gov (United States)

    Kisiela, Michael; Faust, Annette; Ebert, Bettina; Maser, Edmund; Scheidig, Axel J

    2018-01-01

    The human dehydrogenase/reductase SDR family member 4 (DHRS4) is a tetrameric protein that is involved in the metabolism of several aromatic carbonyl compounds, steroids, and bile acids. The only invertebrate DHRS4 that has been characterized to date is that from the model organism Caenorhabditis elegans. We have previously cloned and initially characterized this protein that was recently annotated as DHRS4_CAEEL in the UniProtKB database. Crystallization and X-ray diffraction studies of the full-length DHRS4_CAEEL protein in complex with diacetyl revealed its tetrameric structure and showed that two subunits are connected via an intermolecular disulfide bridge that is formed by N-terminal cysteine residues (Cys5) of each protein chain, which increases the enzymatic activity. A more detailed biochemical and catalytic characterization shows that DHRS4_CAEEL shares some properties with human DHRS4 such as relatively low substrate affinities with aliphatic α-diketones and a preference for aromatic dicarbonyls such as isatin, with a 30-fold lower Km value compared with the human enzyme. Moreover, DHRS4_CAEEL is active with aliphatic aldehydes (e.g. hexanal), while human DHRS4 is not. Dehydrogenase activity with alcohols was only observed with aromatic alcohols. Protein thermal shift assay revealed a stabilizing effect of phosphate buffer that was accompanied by an increase in catalytic activity of more than two-fold. The study of DHRS4 homologs in simple lineages such as C. elegans may contribute to our understanding of the original function of this protein that has been shaped by evolutionary processes in the course of the development from invertebrates to higher mammalian species. Structural data are available in the PDB under the accession numbers 5OJG and 5OJI. © 2017 Federation of European Biochemical Societies.

  15. Selective Production of Aromatic Aldehydes from Heavy Fraction of Bio-oil via Catalytic Oxidation

    International Nuclear Information System (INIS)

    Li, Yan; Chang, Jie; Ouyang, Yong; Zheng, Xianwei

    2014-01-01

    High value-added aromatic aldehydes (e. g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide (H 2 O 2 ) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin (Co(TPPS 4 )) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without Co(TPPS 4 ). Moreover, a possible mechanism of HFBO oxidation using Co(TPPS 4 )/H 2 O 2 was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under Co(TPPS 4 )/H 2 O 2 system

  16. Prevention of hepatitis B virus transmission by the gastrointestinal fibrescope. Successful disinfection with an aldehyde liquid.

    Science.gov (United States)

    Seefeld, U; Bansky, G; Jaeger, M; Schmid, M

    1981-11-01

    In a prospective study we examined the efficacy of a standardized disinfection method in preventing the transmission of hepatitis B virus by the gastrointestinal fibrescope. Four HBSAg- and Dane particle-positive patients who have been endoscoped served as possible sources of hepatitis B virus infection. We cleaned the instrument with a 10% aldehyde liquid and used it immediately thereafter in 10 HBSAg-negative patients. Eight of them were followed-up for 7 months after the endoscopic procedure. None of them showed serological evidence of an endoscopically transmitted hepatitis B virus infection. It is concluded that disinfection with an aldehyde liquid is effective in preventing the transmission of hepatitis B virus by the fibrescope.

  17. Cyclic voltammetric behaviour of dimensionally stable anodes in the presence of C1 - C3 aldehydes

    Directory of Open Access Journals (Sweden)

    Malpass Geoffroy R. P.

    2003-01-01

    Full Text Available This work describes the cyclic voltammetry study of three aliphatic aldehydes: formaldehyde, acetaldehyde and propionaldehyde at dimensionally stable anodes (DSA®. Electrodes of nominal composition Ti/Ru0.3M0.7O2 (where M = Ti ou Sn were used in 0.5 mol dm-3 H2SO4 in a filter-press cell. Both electrodes exhibit behaviour typical of such materials in the presence of formaldehyde. However, with acetaldehyde and propionaldehyde non-typical behaviour is observed. This is characterised by a fall in the normalised faradaic anodic charge (q nf and also a decrease in the current density associated with the oxygen evolution reaction (OER. A possible reaction mechanism, considering the direct oxidation of the aldehyde at the electrode surface, is suggested.

  18. Structural basis for the role of mammalian aldehyde oxidases in the metabolism of drugs and xenobiotics.

    Science.gov (United States)

    Romão, Maria João; Coelho, Catarina; Santos-Silva, Teresa; Foti, Alessandro; Terao, Mineko; Garattini, Enrico; Leimkühler, Silke

    2017-04-01

    Aldehyde oxidases (AOXs) are molybdo-flavoenzymes characterized by broad substrate specificity, oxidizing aromatic/aliphatic aldehydes into the corresponding carboxylic acids and hydroxylating various heteroaromatic rings. Mammals are characterized by a complement of species-specific AOX isoenzymes, that varies from one in humans (AOX1) to four in rodents (AOX1, AOX2, AOX3 and AOX4). The physiological function of mammalian AOX isoenzymes is unknown, although human AOX1 is an emerging enzyme in phase-I drug metabolism. Indeed, the number of therapeutic molecules under development which act as AOX substrates is increasing. The recent crystallization and structure determination of human AOX1 as well as mouse AOX3 has brought new insights into the mechanisms underlying substrate/inhibitor binding as well as the catalytic activity of this class of enzymes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Biomass Vanillin-Derived Polymeric Microspheres Containing Functional Aldehyde Groups: Preparation, Characterization, and Application as Adsorbent.

    Science.gov (United States)

    Zhang, Huanyu; Yong, Xueyong; Zhou, Jinyong; Deng, Jianping; Wu, Youping

    2016-02-03

    The contribution reports the first polymeric microspheres derived from a biomass, vanillin. It reacted with methacryloyl chloride, providing monomer vanillin methacrylate (VMA), which underwent suspension polymerization in aqueous media and yielded microspheres in high yield (>90 wt %). By controlling the N2 bubbling mode and by optimizing the cosolvent for dissolving the solid monomer, the microspheres were endowed with surface pores, demonstrated by SEM images and mercury intrusion porosimetry measurement. Taking advantage of the reactive aldehyde groups, the microspheres further reacted with glycine, thereby leading to a novel type of Schiff-base chelating material. The functionalized microspheres demonstrated remarkable adsorption toward Cu(2+) (maximum, 135 mg/g) which was taken as representative for metal ions. The present study provides an unprecedented class of biobased polymeric microspheres showing large potentials as adsorbents in wastewater treatment. Also importantly, the reactive aldehyde groups may enable the microspheres to be used as novel materials for immobilizing biomacromolecules, e.g. enzymes.

  20. A Green Approach for Allylations of Aldehydes and Ketones: Combining Allylborate, Mechanochemistry and Lanthanide Catalyst

    Directory of Open Access Journals (Sweden)

    Viviane P. de Souza

    2016-11-01

    Full Text Available Secondary and tertiary alcohols synthesized via allylation of aldehydes and ketones are important compounds in bioactive natural products and industry, including pharmaceuticals. Development of a mechanochemical method using potassium allyltrifluoroborate salt and water, to successfully perform the allylation of aromatic and aliphatic carbonyl compounds is reported for the first time. By controlling the grinding parameters, the methodology can be selective, namely, very efficient for aldehydes and ineffective for ketones, but by employing lanthanide catalysts, the reactions with ketones can become practically quantitative. The catalyzed reactions can also be performed under mild aqueous stirring conditions. Considering the allylation agent and its by-products, aqueous media, energy efficiency and use of catalyst, the methodology meets most of the green chemistry principles.

  1. Green Tea Polyphenols Decrease Strecker Aldehydes and Bind to Proteins in Lactose-Hydrolyzed UHT Milk.

    Science.gov (United States)

    Jansson, Therese; Rauh, Valentin; Danielsen, Bente P; Poojary, Mahesha M; Waehrens, Sandra S; Bredie, Wender L P; Sørensen, John; Petersen, Mikael A; Ray, Colin A; Lund, Marianne N

    2017-12-06

    The effect of epigallocatechin gallate enriched green tea extract (GTE) on flavor, Maillard reactions and protein modifications in lactose-hydrolyzed (LH) ultrahigh temperature (UHT) processed milk was examined during storage at 40 °C for up to 42 days. Addition of GTE inhibited the formation of Strecker aldehydes by up to 95% compared to control milk, and the effect was similar when GTE was added either before or after UHT treatment. Release of free amino acids, caused by proteolysis, during storage was also decreased in GTE-added milk either before or after UHT treatment compared to control milk. Binding of polyphenols to milk proteins was observed in both fresh and stored milk samples. The inhibition of Strecker aldehyde formation by GTE may be explained by two different mechanisms; inhibition of proteolysis during storage by GTE or binding of amino acids and proteins to the GTE polyphenols.

  2. Flavour release of aldehydes and diacetyl in oil/water systems

    DEFF Research Database (Denmark)

    Haahr, Anne-Mette; Bredie, W. L. P.; Stahnke, Louise Heller

    2000-01-01

    from the pure oil. The release over time for diacetyl and (E,E)-2,4-hexadienal showed a linear relationship in all systems. The other compounds followed an exponential relationship between the time and the fraction released in the aqueous systems. It was demonstrated that the release of the volatile...... compounds was dependent on the chain length, the degree of unsaturation as well as the characteristics of the model system. (C) 2000 Elsevier Science Ltd. All rights reserved.......The concentration- and time-dependent release of three C-6-aldehydes, six C-9-aldehydes and diacetyl was studied in model systems. The systems were water, rapeseed oil and oil-in-water emulsions. Dynamic headspace sampling was used to collect the volatile compounds. In the concentration...

  3. The structure of the quinoprotein alcohol dehydrogenase of Acetobacter aceti modelled on that of methanol dehydrogenase from Methylobacterium extorquens.

    Science.gov (United States)

    Cozier, G E; Giles, I G; Anthony, C

    1995-06-01

    The 1.94 A structure of methanol dehydrogenase has been used to provide a model structure for part of a membrane quinohaemoprotein alcohol dehydrogenase. The basic superbarrel structure and the active-site region are retained, indicating essentially similar mechanisms of action, but there are considerable differences in the external loops, particularly those involved in formation of the shallow funnel leading to the active site.

  4. Relative reactivity of oxygenated fuels: alcohols, aldehydes, ketons and methyl esters.

    OpenAIRE

    Pelucchi, Matteo; Cavallotti, Carlo; Ranzi, Eliseo; Frassoldati, Alessio; Faravelli, Tiziano

    2016-01-01

    This work aims at comparing and highlighting the main reaction pathways, characterizing the combustion behavior of oxygenated fuels. Ethanol and heavier alcohols are already viable biofuels, despite some concern on their aldehyde and ketone emissions. Recently, the potential of 2-butanone (methyl ethyl ketone) as anti-knocking fuel was investigated at engine relevant conditions. Moving from methyl butanoate, long chain fatty acid methyl esters are largely considered and used as bi...

  5. Interaction of α,β-unsaturated aldehydes with dienes in the presence of boron trifluoride etherate

    International Nuclear Information System (INIS)

    Gramenitskaya, V.N.; Golovkina, L.S.; Orach, V.S.

    1975-01-01

    The products of the acrolein reaction with divinyl, isoprene and chloroprene catalized by BF 3 xEt 2 O are corresponding 3-cyclohexenaldehydes trimerized under the catalyst influence. Mixtures of substituted 3-cyclohexealdehydes and Δ 3 -dihydropirines were produced as results of the reaction of croton aldehyde with 1,1,3-trimethilbutadiene at high temperature as well as at 20 deg C in presence of catalyst

  6. Enantioselective α-Vinylation of Aldehydes Via the Synergistic Combination of Copper and Amine Catalysis

    Science.gov (United States)

    Skucas, Eduardas; MacMillan, David W. C.

    2012-01-01

    The enantioselective α-vinylation of aldehydes using vinyl iodonium triflate salts has been accomplished via the synergistic combination of copper and chiral amine catalysis. These mild catalytic conditions provide a direct route for the enantioselective construction of enolizable α-formyl vinylic stereocenters without racemization or olefin transposition. These high-value coupling adducts are readily converted into a variety of useful olefin synthons. PMID:22616631

  7. Total Synthesis of Chiral Falcarindiol Analogues Using BINOL-Promoted Alkyne Addition to Aldehydes

    OpenAIRE

    Li Wang; Ping-Ping Shou; Si-Ping Wei; Chun Zhang; Shuang-Xun Li; Ping-Xian Liu; Xi Du; Qin Wang

    2016-01-01

    An enantioselective total synthesis of chiral falcarindiol analogues from buta-1,3-diyn-1-yltriisopropylsilane is reported. The key step in this synthesis is BINOL-promoted asymmetric diacetylene addition to aldehydes. The two chiral centers of the falcarindiol analogues can be produced by using the same kind of catalyst with high selectivity, and the final product can be obtained in only six steps.

  8. Total Synthesis of Chiral Falcarindiol Analogues Using BINOL-Promoted Alkyne Addition to Aldehydes

    Directory of Open Access Journals (Sweden)

    Li Wang

    2016-01-01

    Full Text Available An enantioselective total synthesis of chiral falcarindiol analogues from buta-1,3-diyn-1-yltriisopropylsilane is reported. The key step in this synthesis is BINOL-promoted asymmetric diacetylene addition to aldehydes. The two chiral centers of the falcarindiol analogues can be produced by using the same kind of catalyst with high selectivity, and the final product can be obtained in only six steps.

  9. Total Synthesis of Chiral Falcarindiol Analogues Using BINOL-Promoted Alkyne Addition to Aldehydes.

    Science.gov (United States)

    Wang, Li; Shou, Ping-Ping; Wei, Si-Ping; Zhang, Chun; Li, Shuang-Xun; Liu, Ping-Xian; Du, Xi; Wang, Qin

    2016-01-19

    An enantioselective total synthesis of chiral falcarindiol analogues from buta-1,3-diyn-1-yltriisopropylsilane is reported. The key step in this synthesis is BINOL-promoted asymmetric diacetylene addition to aldehydes. The two chiral centers of the falcarindiol analogues can be produced by using the same kind of catalyst with high selectivity, and the final product can be obtained in only six steps.

  10. Aerobic oxidation of aldehydes under ambient conditions using supported gold nanoparticle catalysts

    DEFF Research Database (Denmark)

    Marsden, Charlotte Clare; Taarning, Esben; Hansen, David

    2008-01-01

    A new, green protocol for producing simple esters by selectively oxidizing an aldehyde dissolved in a primary alcohol has been established, utilising air as the oxidant and supported gold nanoparticles as catalyst. The oxidative esterifications proceed with excellent selectivities at ambient...... conditions; the reactions can be performed in an open flask and at room temperature. Benzaldehyde is even oxidised at a reasonable rate below -70 degrees C. Acrolein is oxidised to methyl acrylate in high yield using the same protocol....

  11. Genotoxic consequences of endogenous aldehydes on mouse haematopoietic stem cell function.

    Science.gov (United States)

    Garaycoechea, Juan I; Crossan, Gerry P; Langevin, Frederic; Daly, Maria; Arends, Mark J; Patel, Ketan J

    2012-09-27

    Haematopoietic stem cells (HSCs) regenerate blood cells throughout the lifespan of an organism. With age, the functional quality of HSCs declines, partly owing to the accumulation of damaged DNA. However, the factors that damage DNA and the protective mechanisms that operate in these cells are poorly understood. We have recently shown that the Fanconi anaemia DNA-repair pathway counteracts the genotoxic effects of reactive aldehydes. Mice with combined inactivation of aldehyde catabolism (through Aldh2 knockout) and the Fanconi anaemia DNA-repair pathway (Fancd2 knockout) display developmental defects, a predisposition to leukaemia, and are susceptible to the toxic effects of ethanol-an exogenous source of acetaldehyde. Here we report that aged Aldh2(-/-) Fancd2(-/-) mutant mice that do not develop leukaemia spontaneously develop aplastic anaemia, with the concomitant accumulation of damaged DNA within the haematopoietic stem and progenitor cell (HSPC) pool. Unexpectedly, we find that only HSPCs, and not more mature blood precursors, require Aldh2 for protection against acetaldehyde toxicity. Additionally, the aldehyde-oxidizing activity of HSPCs, as measured by Aldefluor stain, is due to Aldh2 and correlates with this protection. Finally, there is more than a 600-fold reduction in the HSC pool of mice deficient in both Fanconi anaemia pathway-mediated DNA repair and acetaldehyde detoxification. Therefore, the emergence of bone marrow failure in Fanconi anaemia is probably due to aldehyde-mediated genotoxicity restricted to the HSPC pool. These findings identify a new link between endogenous reactive metabolites and DNA damage in HSCs, and define the protective mechanisms that counteract this threat.

  12. Dirhodium carboxylates catalyzed enantioselective coupling reactions of α-diazophosphonates, anilines, and electron-deficient aldehydes.

    Science.gov (United States)

    Zhou, Cong-Ying; Wang, Jing-Cui; Wei, Jinhu; Xu, Zhen-Jiang; Guo, Zhen; Low, Kam-Hung; Che, Chi-Ming

    2012-11-05

    Chiral dirhodium carboxylate complexes ([Rh(2)(S-PTAD)(4)] or [Rh(2)(S-PTTL)(4)]) efficiently catalyze asymmetric three-component coupling reactions of α-diazophosphonates, anilines, and electron-deficient aldehydes to give α-amino-β-hydroxyphosphonates. The high level of enantiocontrol provides evidence for the intermediacy of metal-bound ammonium ylide in the product-forming step. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Exposure to polycyclic aromatic hydrocarbons (PAHs), mutagenic aldehydes and particulate matter during pan frying of beefsteak.

    Science.gov (United States)

    Sjaastad, Ann Kristin; Jørgensen, Rikke Bramming; Svendsen, Kristin

    2010-04-01

    Cooking with gas or electric stoves produces fumes, especially during frying, that contain a range of harmful and potentially mutagenic compounds as well as high levels of fine and ultrafine particles. The aim of this study was to see if polycyclic aromatic hydrocarbons (PAHs) and higher mutagenic aldehydes which were collected in the breathing zone of the cook, could be detected in fumes from the frying of beefsteak. The frying was performed in a model kitchen in conditions similar to those in a Western European restaurant kitchen. The levels of PAHs (16 EPA standard) and higher aldehydes (trans,trans-2,4-decadienal, 2,4-decadienal, trans-trans-2,4-nonadienal, trans-2-decenal, cis-2-decenal, trans-2-undecenal, 2-undecenal) were measured during frying on an electric or gas stove with margarine or soya bean oil as the frying fat. The number concentration of particles <100 nm in size (ultrafine) was also measured, as well as the mass concentration of total particulate matter. Levels of naphthalene were in the range of 0.15-0.27 microg/m(3) air. Measured levels of mutagenic aldehydes were between non-detectable and 61.80 microg/m(3) air. The exposure level of total aerosol was between 1.6 and 7.2 mg/m(3) air. Peak number concentrations of ultrafine particles were in the range of 6.0x10(4)-89.6x10(4) particles/cm(3) air. Naphthalene and mutagenic aldehydes were detected in most of the samples. The levels were variable, and seemed to be dependent on many factors involved in the frying process. However, according to the present results, frying on a gas stove instead of an electric stove causes increased occupational exposure to some of the components in cooking fumes which may cause adverse health effects.

  14. Antibacterial activity of Mannich bases derived from 2-naphthols, aromatic aldehydes and secondary aliphatic amines.

    Science.gov (United States)

    Roman, Gheorghe; Năstasă, Valentin; Bostănaru, Andra-Cristina; Mareş, Mihai

    2016-05-15

    A small library of 1-aminoalkyl 2-naphthols has been synthesized through the direct Mannich reaction of 2-naphthols with (hetero)aromatic aldehydes and secondary amines. All of the Mannich bases having a thiophen-2-yl ring in their structure had good activity against Gram-positive bacteria, irrespective of the nature of the amino moiety. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. ald of Mycobacterium tuberculosis Encodes both the Alanine Dehydrogenase and the Putative Glycine Dehydrogenase

    Science.gov (United States)

    Giffin, Michelle M.; Modesti, Lucia; Raab, Ronald W.; Wayne, Lawrence G.

    2012-01-01

    The putative glycine dehydrogenase of Mycobacterium tuberculosis catalyzes the reductive amination of glyoxylate to glycine but not the reverse reaction. The enzyme was purified and identified as the previously characterized alanine dehydrogenase. The Ald enzyme was expressed in Escherichia coli and had both pyruvate and glyoxylate aminating activities. The gene, ald, was inactivated in M. tuberculosis, which resulted in the loss of all activities. Both enzyme activities were found associated with the cell and were not detected in the extracellular filtrate. By using an anti-Ald antibody, the protein was localized to the cell membrane, with a smaller fraction in the cytosol. None was detected in the extracellular medium. The ald knockout strain grew without alanine or glycine and was able to utilize glycine but not alanine as a nitrogen source. Transcription of ald was induced when alanine was the sole nitrogen source, and higher levels of Ald enzyme were measured. Ald is proposed to have several functions, including ammonium incorporation and alanine breakdown. PMID:22210765

  16. Effect of fermented sea tangle on the alcohol dehydrogenase and acetaldehyde dehydrogenase in Saccharomyces cerevisiae.

    Science.gov (United States)

    Cha, Jae-Young; Jeong, Jae-Jun; Yang, Hyun-Ju; Lee, Bae-Jin; Cho, Young-Su

    2011-08-01

    Sea tangle, a kind of brown seaweed, was fermented with Lactobacillus brevis BJ-20. The gamma-aminobutyric acid (GABA) content in fermented sea tangle (FST) was 5.56% (w/w) and GABA in total free amino acid of FST was 49.5%. The effect of FST on the enzyme activities and mRNA protein expression of alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) involved in alcohol metabolism in Saccharomyces cerevisiae was investigated. Yeast was cultured in YPD medium supplemented with different concentrations of FST powder [0, 0.4, 0.8, and 1.0% (w/v)] for 18 h. FST had no cytotoxic effect on the yeast growth. The highest activities and protein expressions of ADH and ALDH from the cell-free extracts of S. cerevisiae were evident with the 0.4% and 0.8% (w/v) FST-supplemented concentrations, respectively. The highest concentrations of GABA as well as minerals (Zn, Ca, and Mg) were found in the cell-free extracts of S. cerevisiae cultured in medium supplemented with 0.4% (w/v) FST. The levels of GABA, Zn, Ca, and Mg in S. cerevisiae were strongly correlated with the enzyme activities of ADH and ALDH in yeast. These results indicate that FST can enhance the enzyme activities and protein expression of ADH and ALDH in S. cerevisiae.

  17. Transcriptome analysis of Zymomonas mobilis ZM4 reveals mechanisms of tolerance and detoxification of phenolic aldehyde inhibitors from lignocellulose pretreatment

    Science.gov (United States)

    Background: Phenolic aldehydes generated from lignocellulose pretreatment exhibited severe toxic inhibitions on microbial growth and fermentation. Numerous tolerance studies against furfural, 5-hydroxymethyl-2-furaldehyde (HMF), acetate, and ethanol were reported, but studies on inhibition of phenol...

  18. Identification and characterization of aldehyde oxidases (AOXs) in the cotton bollworm

    Science.gov (United States)

    Xu, Wei; Liao, Yalin

    2017-12-01

    Aldehyde oxidases (AOXs) are a family of metabolic enzymes that oxidize aldehydes into carboxylic acids; therefore, they play critical roles in detoxification and degradation of chemicals. By using transcriptomic and genomic approaches, we successfully identified six putative AOX genes (HarmAOX1-6) from cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). In silico expression profile, reverse transcription (RT)-PCR, and quantitative PCR (qPCR) analyses showed that HarmAOX1 is highly expressed in adult antennae, tarsi, and larval mouthparts, so they may play an important role in degrading plant-derived compounds. HarmAOX2 is highly and specifically expressed in adult antennae, suggesting a candidate pheromone-degrading enzyme (PDE) to inactivate the sex pheromone components (Z)-11-hexadecenal and (Z)-9-hexadecenal. RNA sequencing data further demonstrated that a number of host plants they feed on could significantly upregulate the expression levels of HarmAOX1 in larvae. This study improves our understanding of insect aldehyde oxidases and insect-plant interactions.

  19. Biochemical and spectroscopic characterization of an aldehyde oxidoreductase isolated from Desulfovibrio aminophilus.

    Science.gov (United States)

    Thapper, Anders; Rivas, Maria G; Brondino, Carlos D; Ollivier, Bernard; Fauque, Guy; Moura, Isabel; Moura, José J G

    2006-01-01

    Aldehyde oxidoreductase (AOR) activity has been found in a number of sulfate-reducing bacteria. The enzyme that is responsible for the conversion of aldehydes to carboxylic acids is a mononuclear molybdenum enzyme belonging to the xanthine oxidase family. We report here the purification and characterization of AOR isolated from the sulfate-reducing bacterium Desulfovibrio (D.) aminophilus DSM 12254, an aminolytic strain performing thiosulfate dismutation. The enzyme is a homodimer (ca. 200 kDa), containing a molybdenum centre and two [2Fe-2S] clusters per monomer. UV/Visible and electron paramagnetic resonance (EPR) spectra of D. aminophilus AOR recorded in as-prepared and reduced states are similar to those obtained in AORs from Desulfovibrio gigas, Desulfovibrio desulfuricans and Desulfovibrio alaskensis. Despite AOR from D. aminophilus is closely related to other AORs, it presents lower activity towards aldehydes and no activity towards N-heterocyclic compounds, which suggests another possible role for this enzyme in vivo. A comparison of the molecular and EPR properties of AORs from different Desulfovibrio species is also included.

  20. Iron(III) and aluminium(III) complexes with substituted salicyl-aldehydes and salicylic acids.

    Science.gov (United States)

    Nurchi, Valeria M; Crespo-Alonso, Miriam; Toso, Leonardo; Lachowicz, Joanna I; Crisponi, Guido; Alberti, Giancarla; Biesuz, Raffaela; Domínguez-Martín, Alicia; Niclós-Gutíerrez, Juan; González-Pérez, Josefa M; Zoroddu, M Antonietta

    2013-11-01

    The chelating properties toward iron(III) and aluminium(III) of variously substituted salicyl-aldehydes and salicylic acids have been evaluated, together with the effect of methoxy and nitro substituents in ortho and para position with respect to the phenolic group. The protonation and iron and aluminium complex formation equilibria have been studied by potentiometry, UV-visible spectrophotometry and (1)H NMR spectroscopy. The overall results highlight that salicyl-aldehydes present good chelating properties toward iron(III), with pFe ranging from 14.2 with nitro to 15.7 with methoxy substituent, being ineffective toward aluminium; the pFe values for salicylic acids are generally lower than those for salicyl-aldehydes, and about 4 units higher than the corresponding pAl values. The effect of the two substituents on the chelating properties of the ligands can be rationalized in terms of the Swain-Lupton treatment which accounts for the field and resonance effects. The structural characterization of the 1:2 iron complex with p-nitro salicylic acid shows that iron(III) ion exhibits an octahedral surrounding where two salicylate chelating ligands supply two O-phenolate and two O-carboxylate donor atoms in a roughly equatorial plane. The trans-apical sites are occupied by two aqua ligands. © 2013.

  1. Plant volatile aldehydes as natural insecticides against stored-product beetles.

    Science.gov (United States)

    Hubert, Jan; Münzbergová, Zuzana; Santino, Angelo

    2008-01-01

    Infestation by stored-product pests causes serious losses in food and feed commodities. Among possible strategies against these pests, which aim to reduce the use of synthetic insecticides, including fumigants, natural insecticides produced by plants represent one of the most promising approaches for their ecochemical control. Three six-carbon and nine-carbon aldehydes, natural plant volatiles produced by the plant lipoxygenase pathway, were tested for their insecticidal activity against five species of stored-product beetles in feeding, fumigation and combined bioassays. The compounds (2E,6Z)-nonadienal, (2E)-nonenal and (2E)-hexenal were incorporated into feeding discs in feeding bioassays or evaporated from filter paper in closed glass chambers in fumigation tests. Beetle sensitivity to aldehydes differed according to the different treatments. The highest activity was obtained by (2E)-hexenal in fumigation tests, with the LC(50) ranging from 4 to 26 mg L(-1), while (2E, 6Z)-nonadienal was the most effective in feeding tests, giving LD(50)s ranging from 0.44 to 2.76 mg g(-1) when applied to feeding discs. Fumigation tests in the presence of wheat grains confirmed that (2E)-hexenal was the most effective compound, with a calculated LC(99) ranging from 33 to 166 mg L(-1). The results of both feeding and fumigation tests indicated that natural plant aldehydes are potential candidates to control stored-product beetles.

  2. A catalytic reactor for the organocatalyzed enantioselective continuous flow alkylation of aldehydes.

    Science.gov (United States)

    Porta, Riccardo; Benaglia, Maurizio; Puglisi, Alessandra; Mandoli, Alessandro; Gualandi, Andrea; Cozzi, Pier Giorgio

    2014-12-01

    The use of immobilized metal-free catalysts offers the unique possibility to develop sustainable processes in flow mode. The challenging intermolecular organocatalyzed enantioselective alkylation of aldehydes was performed for the first time under continuous flow conditions. By using a packed-bed reactor filled with readily available supported enantiopure imidazolidinone, different aldehydes were treated with three distinct cationic electrophiles. In the organocatalyzed α-alkylation of aldehydes with 1,3-benzodithiolylium tetrafluoroborate, excellent enantioselectivities, in some cases even better than those obtained in the flask process (up to 95% ee at 25 °C), and high productivity (more than 3800 h(-1) ) were obtained, which thus shows that a catalytic reactor may continuously produce enantiomerically enriched compounds. Treatment of the alkylated products with Raney-nickel furnished enantiomerically enriched α-methyl derivatives, key intermediates for active pharmaceutical ingredients and natural products. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Electrochemical impedance spectroscopy measurements for determination of derivatized aldehydes in several matrices

    Directory of Open Access Journals (Sweden)

    W. Boumya

    2017-10-01

    Full Text Available A simple, selective and sensitive electrochemical method is described for the determination of different aldehydes at glassy carbon electrode using electrochemical impedance spectroscopy (EIS. The measurements were performed after their derivatization with 2,4-dinitrophenylhydrazine (DNPH in acidic medium. The impedance measurements were investigated in the frequency range from 100 mHz to 100 kHz at a potential of 1.0 V versus Ag/AgCl. The Nyquist plots were modeled with a Randle’s equivalent circuit. The charge transfer resistance was identified as the dependent parameter on relevant concentration of aldehydes (determined as their hydrazones. Under the optimized conditions, the linearity was established over the concentration range of 1000–0.05 μmol L−1. The limits of detection (LODs obtained were from 0.097 to 0.0109 μmol L−1. Finally, the developed method has been applied to the determination of aldehydes in drinking water, orange juice and apple vinegar samples with relative standard deviations (RSDs < 3.1% and acceptable recovery rate (around of 80%. Keyword: Food analysis

  4. Reaction of arylsulfonylhydrazones of aldehydes with alpha-magnesio sulfones. A novel olefin synthesis.

    Science.gov (United States)

    Kurek-Tyrlik, A; Marczak, S; Michalak, K; Wicha, J; Zarecki, A

    2001-10-19

    Reactions of representative tosylhydrazones of aldehydes and ketones with alpha-metalated sulfones were examined in order to develop a practical olefination method. Treatment of aldehyde tosylhydrazone 2 with an excess of alpha-lithiated methyl phenyl or dimethyl sulfones yielded 3a. The reaction of 2 with sterically unhindered lithiated alkyl sulfones gave mixtures of the respective olefination products 3b-d along with the Shapiro fragmentation product 4. Sterically hindered lithiated sulfones afforded Shapiro products exclusively. In contrast, aldehyde tosylhydrazones 2 or 6 in reactions with a variety of alpha-magnesio primary or secondary alkyl sulfones gave olefination products 3a-j and 7a-c in high yields (Tables 1 and 2). beta-Branched alkyl sulfones afforded predominantly (E)-alkenes, whereas unhindered primary sulfones gave mixtures of (E)- and (Z)-alkenes with low selectivity. Reaction of the 2,4,6-triisopropylbenzenesulfonylhydrazone (trisylhydrazone) of cyclodecanone 11c with alpha-magnesio methyl phenyl sulfone afforded the methylidene derivative 12a contaminated with the Shapiro product 13. Tosylhydrazone 2 resisted reaction with i-PrMgCl and gave only a small amount of the addition product in reaction with Bu(2)Mg. Some mechanistic aspects of the reaction of tosylhydrazones with organomagnesium compounds are discussed.

  5. Drude polarizable force field for aliphatic ketones and aldehydes, and their associated acyclic carbohydrates

    Science.gov (United States)

    Small, Meagan C.; Aytenfisu, Asaminew H.; Lin, Fang-Yu; He, Xibing; MacKerell, Alexander D.

    2017-04-01

    The majority of computer simulations exploring biomolecular function employ Class I additive force fields (FF), which do not treat polarization explicitly. Accordingly, much effort has been made into developing models that go beyond the additive approximation. Development and optimization of the Drude polarizable FF has yielded parameters for selected lipids, proteins, DNA and a limited number of carbohydrates. The work presented here details parametrization of aliphatic aldehydes and ketones (viz. acetaldehyde, propionaldehyde, butaryaldehyde, isobutaryaldehyde, acetone, and butanone) as well as their associated acyclic sugars ( d-allose and d-psicose). LJ parameters are optimized targeting experimental heats of vaporization and molecular volumes, while the electrostatic parameters are optimized targeting QM water interactions, dipole moments, and molecular polarizabilities. Bonded parameters are targeted to both QM and crystal survey values, with the models for ketones and aldehydes shown to be in good agreement with QM and experimental target data. The reported heats of vaporization and molecular volumes represent a compromise between the studied model compounds. Simulations of the model compounds show an increase in the magnitude and the fluctuations of the dipole moments in moving from gas phase to condensed phases, which is a phenomenon that the additive FF is intrinsically unable to reproduce. The result is a polarizable model for aliphatic ketones and aldehydes including the acyclic sugars d-allose and d-psicose, thereby extending the available biomolecules in the Drude polarizable FF.

  6. Reductive detoxification of acrolein as a potential role for aldehyde reductase (AKR1A) in mammals.

    Science.gov (United States)

    Kurahashi, Toshihiro; Kwon, Myoungsu; Homma, Takujiro; Saito, Yuka; Lee, Jaeyong; Takahashi, Motoko; Yamada, Ken-Ichi; Miyata, Satoshi; Fujii, Junichi

    2014-09-12

    Aldehyde reductase (AKR1A), a member of the aldo-keto reductase superfamily, suppresses diabetic complications via a reduction in metabolic intermediates; it also plays a role in ascorbic acid biosynthesis in mice. Because primates cannot synthesize ascorbic acid, a principle role of AKR1A appears to be the reductive detoxification of aldehydes. In this study, we isolated and immortalized mouse embryonic fibroblasts (MEFs) from wild-type (WT) and human Akr1a-transgenic (Tg) mice and used them to investigate the potential roles of AKR1A under culture conditions. Tg MEFs showed higher methylglyoxal- and acrolein-reducing activities than WT MEFs and also were more resistant to cytotoxicity. Enzymatic analyses of purified rat AKR1A showed that the efficiency of the acrolein reduction was about 20% that of glyceraldehyde. Ascorbic acid levels were quite low in the MEFs, and while the administration of ascorbic acid to the cells increased the intracellular levels of ascorbic acid, it had no affect on the resistance to acrolein. Endoplasmic reticulum stress and protein carbonylation induced by acrolein treatment were less evident in Tg MEFs than in WT MEFs. These data collectively indicate that one of the principle roles of AKR1A in primates is the reductive detoxification of aldehydes, notably acrolein, and protection from its detrimental effects. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Enhancing the reaction rates of Morita-Baylis-Hillman reaction in heterocyclic aldehydes by substitutions.

    Science.gov (United States)

    Kunnikuruvan, Sooraj; Batra, Sanjay; Nair, Nisanth N

    2012-11-12

    The molecular origin of the experimentally observed pronounced difference in the rates of Morita-Baylis-Hillman (MBH) reaction in heterocyclic aldehydes, depending on the position of the formyl group, is investigated herein by using DFT-based mechanistic studies and free energy computations. These calculations are based on the 1,4-diazobicyclo[2.2.2]octane (DABCO)-catalyzed MBH reaction of methyl acrylate with substituted 4- and 5-isoxazolecarbaldehyde, which are slow- and fast-reacting substrates, respectively. As a result of this study, we propose that by tailoring ring substitutions the reactivity of the formyl group for MBH reactions may be enhanced in slow-reacting heterocyclic aldehydes. This proposition is demonstrated by enhancing the rate of the MBH reaction in 4-isoxazolecarbaldehyde more than 10(4) -fold by installing an ester substitution at the C-3 position. Similarly, the reactivity of the formyl group towards the MBH reaction in substituted 3-pyrazolecarbaldehyde and pyridinecarbaldehyde is shown to be increased several-fold by a halo substitution. We also confirm that the reasons for different reactivities of heterocyclic aldehydes and the proposed scheme for improving the reaction rates remains valid for all the three mechanisms proposed for the MBH reaction, namely, Hill-Isaacs, McQuade, and Aggarwal. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Purification and Properties of an NADPH-Aldose Reductase (Aldehyde Reductase) from Euonymus japonica Leaves

    Science.gov (United States)

    Negm, Fayek B.

    1986-01-01

    The enzyme aldose (aldehyde) reductase was partially purified (142-fold) and characterized from Euonymus japonica leaves. The reductase, a dimer, had an average molecular weight of 67,000 as determined by gel filtration on Sephadex G-100. The enzyme was NADPH specific and reduced a broad range of substrates including aldoses, aliphatic aldehydes, and aromatic aldehydes. Maximum activity was observed at pH 8 in phosphate and Tris-HCl buffers and at pH 8.6 to 9.0 in glycine-NaOH buffer using dl-glyceraldehyde or 3-pyridinecarboxaldehyde as substrate. NADP was a competitive inhibitor with respect to NADPH with a Ki of 60 micromolar. Glycerol was an uncompetitive inhibitor to dl-glyceraldehyde (K′i = 460 millimolar). The Euonymus enzyme was inhibited by sulfhydryl inhibitor, phenobarbital, and high concentrations of Li2SO4. Pyrazol and metal chelating agents inhibited the enzyme slightly. Enzyme activity was detected in the leaves and berries of Celastrus orbiculatus and several species of Euonymus. Probable function of this enzyme is to reduce d-galactose to galactitol, a characteristic metabolite in phloem sap of members of the Celastraceae family. Images Fig. 1 PMID:16664750

  9. Efficient and Highly Selective Solvent-Free Oxidation of Primary Alcohols to Aldehydes Using Bucky Nanodiamond.

    Science.gov (United States)

    Lin, Yangming; Wu, Kuang-Hsu Tim; Yu, Linhui; Heumann, Saskia; Su, Dang Sheng

    2017-09-11

    Selective oxidation of alcohols to aldehydes is widely applicable to the synthesis of various green chemicals. The poor chemoselectivity for complicated primary aldehydes over state-of-the-art metal-free or metal-based catalysts represents a major obstacle for industrial application. Bucky nanodiamond is a potential green catalyst that exhibits excellent chemoselectivity and cycling stability for the selective oxidation of primary alcohols in diverse structures (22 examples, including aromatic, substituted aromatic, unsaturated, heterocyclic, and linear chain alcohols) to their corresponding aldehydes. The results are comparable to reported transition-metal catalysts including conventional Pt/C and Ru/C catalysts for certain substrates under solvent-free conditions. The possible activation process of the oxidant and substrates by the surface oxygen groups and defect species are revealed with model catalysts, ex situ electrochemical measurements, and ex situ attenuated total reflectance. The zigzag edges of sp 2 carbon planes are shown to play a key role in these reactions. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Reaction of azides and enolisable aldehydes under the catalysis of organic bases and Cinchona based quaternary ammonium salts.

    Science.gov (United States)

    Destro, Dario; Sanchez, Sandra; Cortigiani, Mauro; Adamo, Mauro F A

    2017-06-21

    Herein we report a two-step sequence for the preparation of amides starting from azides and enolisable aldehydes. The reaction proceeded via the formation of triazoline intermediates that were converted into amides via Lewis acid catalysis. Preliminary studies on the preparation of triazolines under chiral phase transfer catalysis are also presented, demonstrating that enantioenriched amides could be prepared from achiral aldehydes in moderate to low enantioselectivity.

  11. A unified approach for the synthesis of symmetrical and unsymmetrical dibenzyl ethers from aryl aldehydes through reductive etherification

    Directory of Open Access Journals (Sweden)

    J. Sembian Ruso

    2016-05-01

    Full Text Available In this paper, we describe a simple and convenient conversion of aryl aldehydes to symmetrical dibenzyl ethers through reductive etherification. Similarly, unsymmetrical dibenzyl ether was obtained from aryl aldehyde and TES-protected benzyl alcohol. Triethyl silane with catalytic amount of InCl3 was found to be an efficient condition for the reductive etherification. Moreover, it exhibits remarkable functional group compatibility with yield ranging from good to excellent.

  12. Exposure to mutagenic aldehydes and particulate matter during panfrying of beefsteak with margarine, rapeseed oil, olive oil or soybean oil.

    Science.gov (United States)

    Sjaastad, Ann Kristin; Svendsen, Kristin

    2008-11-01

    The aim of the study was to see if a cook could be exposed to mutagenic aldehydes in fumes from frying of beefsteak using margarine, rapeseed oil, soybean oil or virgin olive oil as frying fat. In addition, levels of particle exposure were measured to make the results comparable to other studies. The levels of higher aldehydes and total particles were measured in the breathing zone of the cook during the panfrying of beefsteak with the four different frying fats. In addition, the number of particles in the size intervals 0.3-0.5, 0.5-0.7 and 0.7-1.0 microm in the kitchen was registered. Measured levels of mutagenic aldehydes were between non-detectable and 25.33 microg m(-3) air. The exposure level of total aerosol was between 1.0 and 11.6 mg m(-3). Higher aldehydes were detected in all samples from this study, and mutagenic aldehydes were detected in most of the samples. Frying with margarine gave statistically significantly higher levels of mutagenic aldehydes and particles in all three size fractions than frying with the three different kinds of oil.

  13. Kinetics of soil dehydrogenase in response to exogenous Cd toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Xiangping [College of Natural Resources and Environment, Northwest A& F University, Yangling, 712100, Shaanxi (China); Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, CAS 723 Xingke Rd., Tianhe District, Guangzhou 510650 (China); Wang, Ziquan; Lu, Guannan [College of Natural Resources and Environment, Northwest A& F University, Yangling, 712100, Shaanxi (China); He, Wenxiang, E-mail: wenxianghe@nwafu.edu.cn [College of Natural Resources and Environment, Northwest A& F University, Yangling, 712100, Shaanxi (China); Key Laboratory of Plant Nutrition and Agro-environment in Northwest China, Ministry of Agriculture, Northwest A& F University, Yangling, 712100, Shaanxi (China); Wei, Gehong [College of Life Sciences, Northwest A& F University, Yangling, 712100, Shaanxi (China); Huang, Feng; Xu, Xinlan; Shen, Weijun [Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, CAS 723 Xingke Rd., Tianhe District, Guangzhou 510650 (China)

    2017-05-05

    Highlights: • pH explained 30–45% of the dehydrogenase activity (DHA), V{sub max}, and K{sub m} variations across soils. • Different inhibition mechanism of Cd to DHA varied soil types. • Soil properties and inhibition constant affect the toxicity of Cd. • Reaction constant (k) could indicate sensitively the toxicity of Cd to DHA. - Abstract: Soil dehydrogenase plays a role in the biological oxidation of soil organic matter and can be considered a good measure of the change of microbial oxidative activity under environmental pollutions. However, the kinetic characteristic of soil dehydrogenase under heavy metal stresses has not been investigated thoroughly. In this study, we characterized the kinetic characteristic of soil dehydrogenase in 14 soil types, and investigated how kinetic parameters changed under spiked with different concentrations of cadmium (Cd). The results showed that the K{sub m} and V{sub max} values of soil dehydrogenase was among 1.4–7.3 mM and 15.9–235.2 μM h{sup −1} in uncontaminated soils, respectively. In latosolic red soil and brown soil, the inhibitory kinetic mechanism of Cd to soil dehydrogenase was anticompetitive inhibition with inhibition constants (K{sub i}) of 12 and 4.7 mM, respectively; in other soils belonged to linear mixed inhibition, the values of K{sub i} were between 0.7–4.2 mM. Soil total organic carbon and K{sub i} were the major factors affecting the toxicity of Cd to dehydrogenase activity. In addition, the velocity constant (k) was more sensitive to Cd contamination compared to V{sub max} and K{sub m}, which was established as an early indicator of gross changes in soil microbial oxidative activity caused by Cd contamination.

  14. Kinetics of soil dehydrogenase in response to exogenous Cd toxicity

    International Nuclear Information System (INIS)

    Tan, Xiangping; Wang, Ziquan; Lu, Guannan; He, Wenxiang; Wei, Gehong; Huang, Feng; Xu, Xinlan; Shen, Weijun

    2017-01-01

    Highlights: • pH explained 30–45% of the dehydrogenase activity (DHA), V max , and K m variations across soils. • Different inhibition mechanism of Cd to DHA varied soil types. • Soil properties and inhibition constant affect the toxicity of Cd. • Reaction constant (k) could indicate sensitively the toxicity of Cd to DHA. - Abstract: Soil dehydrogenase plays a role in the biological oxidation of soil organic matter and can be considered a good measure of the change of microbial oxidative activity under environmental pollutions. However, the kinetic characteristic of soil dehydrogenase under heavy metal stresses has not been investigated thoroughly. In this study, we characterized the kinetic characteristic of soil dehydrogenase in 14 soil types, and investigated how kinetic parameters changed under spiked with different concentrations of cadmium (Cd). The results showed that the K m and V max values of soil dehydrogenase was among 1.4–7.3 mM and 15.9–235.2 μM h −1 in uncontaminated soils, respectively. In latosolic red soil and brown soil, the inhibitory kinetic mechanism of Cd to soil dehydrogenase was anticompetitive inhibition with inhibition constants (K i ) of 12 and 4.7 mM, respectively; in other soils belonged to linear mixed inhibition, the values of K i were between 0.7–4.2 mM. Soil total organic carbon and K i were the major factors affecting the toxicity of Cd to dehydrogenase activity. In addition, the velocity constant (k) was more sensitive to Cd contamination compared to V max and K m , which was established as an early indicator of gross changes in soil microbial oxidative activity caused by Cd contamination.

  15. Distinct roles of jasmonates and aldehydes in plant-defense responses.

    Directory of Open Access Journals (Sweden)

    E Wassim Chehab

    Full Text Available BACKGROUND: Many inducible plant-defense responses are activated by jasmonates (JAs, C(6-aldehydes, and their corresponding derivatives, produced by the two main competing branches of the oxylipin pathway, the allene oxide synthase (AOS and hydroperoxide lyase (HPL branches, respectively. In addition to competition for substrates, these branch-pathway-derived metabolites have substantial overlap in regulation of gene expression. Past experiments to define the role of C(6-aldehydes in plant defense responses were biased towards the exogenous application of the synthetic metabolites or the use of genetic manipulation of HPL expression levels in plant genotypes with intact ability to produce the competing AOS-derived metabolites. To uncouple the roles of the C(6-aldehydes and jasmonates in mediating direct and indirect plant-defense responses, we generated Arabidopsis genotypes lacking either one or both of these metabolites. These genotypes were subsequently challenged with a phloem-feeding insect (aphids: Myzus persicae, an insect herbivore (leafminers: Liriomyza trifolii, and two different necrotrophic fungal pathogens (Botrytis cinerea and Alternaria brassicicola. We also characterized the volatiles emitted by these plants upon aphid infestation or mechanical wounding and identified hexenyl acetate as the predominant compound in these volatile blends. Subsequently, we examined the signaling role of this compound in attracting the parasitoid wasp (Aphidius colemani, a natural enemy of aphids. PRINCIPAL FINDINGS: This study conclusively establishes that jasmonates and C(6-aldehydes play distinct roles in plant defense responses. The jasmonates are indispensable metabolites in mediating the activation of direct plant-defense responses, whereas the C(6-aldehyes are not. On the other hand, hexenyl acetate, an acetylated C(6-aldehyde, is the predominant wound-inducible volatile signal that mediates indirect defense responses by directing tritrophic

  16. A Unique Short-Chain Dehydrogenase/Reductase in Arabidopsis Glucose Signaling and Abscisic Acid Biosynthesis and Functions

    Science.gov (United States)

    Cheng, Wan-Hsing; Endo, Akira; Zhou, Li; Penney, Jessica; Chen, Huei-Chi; Arroyo, Analilia; Leon, Patricia; Nambara, Eiji; Asami, Tadao; Seo, Mitsunori; Koshiba, Tomokazu; Sheen, Jen

    2002-01-01

    Glc has hormone-like functions and controls many vital processes through mostly unknown mechanisms in plants. We report here on the molecular cloning of GLUCOSE INSENSITIVE1 (GIN1) and ABSCISIC ACID DEFICIENT2 (ABA2) which encodes a unique Arabidopsis short-chain dehydrogenase/reductase (SDR1) that functions as a molecular link between nutrient signaling and plant hormone biosynthesis. SDR1 is related to SDR superfamily members involved in retinoid and steroid hormone biosynthesis in mammals and sex determination in maize. Glc antagonizes ethylene signaling by activating ABA2/GIN1 and other abscisic acid (ABA) biosynthesis and signaling genes, which requires Glc and ABA synergistically. Analyses of aba2/gin1 null mutants define dual functions of endogenous ABA in inhibiting the postgermination developmental switch modulated by distinct Glc and osmotic signals and in promoting organ and body size and fertility in the absence of severe stress. SDR1 is sufficient for the multistep conversion of plastid- and carotenoid-derived xanthoxin to abscisic aldehyde in the cytosol. The surprisingly restricted spatial and temporal expression of SDR1 suggests the dynamic mobilization of ABA precursors and/or ABA. PMID:12417697

  17. Downregulation of cinnamyl-alcohol dehydrogenase in switchgrass by RNA silencing results in enhanced glucose release after cellulase treatment.

    Science.gov (United States)

    Saathoff, Aaron J; Sarath, Gautam; Chow, Elaine K; Dien, Bruce S; Tobias, Christian M

    2011-01-27

    Cinnamyl alcohol dehydrogenase (CAD) catalyzes the last step in monolignol biosynthesis and genetic evidence indicates CAD deficiency in grasses both decreases overall lignin, alters lignin structure and increases enzymatic recovery of sugars. To ascertain the effect of CAD downregulation in switchgrass, RNA mediated silencing of CAD was induced through Agrobacterium mediated transformation of cv. "Alamo" with an inverted repeat construct containing a fragment derived from the coding sequence of PviCAD2. The resulting primary transformants accumulated less CAD RNA transcript and protein than control transformants and were demonstrated to be stably transformed with between 1 and 5 copies of the T-DNA. CAD activity against coniferaldehyde, and sinapaldehyde in stems of silenced lines was significantly reduced as was overall lignin and cutin. Glucose release from ground samples pretreated with ammonium hydroxide and digested with cellulases was greater than in control transformants. When stained with the lignin and cutin specific stain phloroglucinol-HCl the staining intensity of one line indicated greater incorporation of hydroxycinnamyl aldehydes in the lignin.

  18. Fluorometric Sniff-Cam (Gas-Imaging System) Utilizing Alcohol Dehydrogenase for Imaging Concentration Distribution of Acetaldehyde in Breath and Transdermal Vapor after Drinking.

    Science.gov (United States)

    Iitani, Kenta; Sato, Toshiyuki; Naisierding, Munire; Hayakawa, Yuuki; Toma, Koji; Arakawa, Takahiro; Mitsubayashi, Kohji

    2018-02-20

    Understanding concentration distributions, release sites, and release dynamics of volatile organic compounds (VOCs) from the human is expected to lead to methods for noninvasive disease screening and assessment of metabolisms. In this study, we developed a visualization system (sniff-cam) that enabled one to identify a spatiotemporal change of gaseous acetaldehyde (AcH) in real-time. AcH sniff-cam was composed of a camera, a UV-LED array sheet, and an alcohol dehydrogenase (ADH)-immobilized mesh. A reverse reaction of ADH was employed for detection of gaseous AcH where a relationship between fluorescence intensity from nicotinamide adenine dinucleotide and the concentration of AcH was inversely proportional; thus, the concentration distribution of AcH was measured by detecting the fluorescence decrease. Moreover, the image differentiation method that calculated a fluorescence change rate was employed to visualize a real-time change in the concentration distribution of AcH. The dynamic range of the sniff-cam was 0.1-10 ppm which encompassed breath AcH concentrations after drinking. Finally, the sniff-cam achieved the visualization of the concentration distribution of AcH in breath and skin gas. A clear difference of breath AcH concentration was observed between aldehyde dehydrogenase type 2 active and inactive subjects, which was attributed to metabolic capacities of AcH. AcH in skin gas showed a similar time course of AcH concentration to the breath and a variety of release concentration distribution. Using different NADH-dependent dehydrogenases in the sniff-cam could lead to a versatile method for noninvasive disease screening by acquiring spatiotemporal information on various VOCs in breath or skin gas.

  19. Fiber-Optic Bio-sniffer (Biochemical Gas Sensor) Using Reverse Reaction of Alcohol Dehydrogenase for Exhaled Acetaldehyde.

    Science.gov (United States)

    Iitani, Kenta; Chien, Po-Jen; Suzuki, Takuma; Toma, Koji; Arakawa, Takahiro; Iwasaki, Yasuhiko; Mitsubayashi, Kohji

    2018-02-23

    Volatile organic compounds (VOCs) exhaled in breath have huge potential as indicators of diseases and metabolisms. Application of breath analysis for disease screening and metabolism assessment is expected since breath samples can be noninvasively collected and measured. In this research, a highly sensitive and selective biochemical gas sensor (bio-sniffer) for gaseous acetaldehyde (AcH) was developed. In the AcH bio-sniffer, a reverse reaction of alcohol dehydrogenase (ADH) was employed for reducing AcH to ethanol and simultaneously consuming a coenzyme, reduced form of nicotinamide adenine dinucleotide (NADH). The concentration of AcH can be quantified by fluorescence detection of NADH that was consumed by reverse reaction of ADH. The AcH bio-sniffer was composed of an ultraviolet light-emitting diode (UV-LED) as an excitation light source, a photomultiplier tube (PMT) as a fluorescence detector, and an optical fiber probe, and these three components were connected with a bifurcated optical fiber. A gas-sensing region of the fiber probe was developed with a flow-cell and an ADH-immobilized membrane. In the experiment, after optimization of the enzyme reaction conditions, the selectivity and dynamic range of the AcH bio-sniffer were investigated. The AcH bio-sniffer showed a short measurement time (within 2 min) and a broad dynamic range for determination of gaseous AcH, 0.02-10 ppm, which encompassed a typical AcH concentration in exhaled breath (1.2-6.0 ppm). Also, the AcH bio-sniffer exhibited a high selectivity to gaseous AcH based on the specificity of ADH. The sensor outputs were observed only from AcH-contained standard gaseous samples. Finally, the AcH bio-sniffer was applied to measure the concentration of AcH in exhaled breath from healthy subjects after ingestion of alcohol. As a result, a significant difference of AcH concentration between subjects with different aldehyde dehydrogenase type 2 (ALDH2) phenotypes was observed. The AcH bio-sniffer can be

  20. Dehydrogenase activity of forest soils depends on the assay used

    Science.gov (United States)

    Januszek, Kazimierz; Długa, Joanna; Socha, Jarosław

    2015-01-01

    Dehydrogenases are exclusively intracellular enzymes, which play an important role in the initial stages of oxidation of soil organic matter. One of the most frequently used methods to estimate dehydrogenase activity in soil is based on the use of triphenyltetrazolium chloride as an artificial electron acceptor. The purpose of this study was to compare the activity of dehydrogenases of forest soils with varied physicochemical properties using different triphenyltetrazolium chloride assays. The determination was carried out using the original procedure by Casida et al., a modification of the procedure which involves the use of Ca(OH)2 instead of CaCO3, the Thalmann method, and the assay by Casida et al. without addition of buffer or any salt. Soil dehydrogenase activity depended on the assay used. Dehydrogenase determined by the Casida et al. method without addition of buffer or any salt correlated with the pH values of soils. The autoclaved strongly acidic samples of control soils showed high concentrations of triphenylformazan, probably due to chemical reduction of triphenyltetrazolium chloride. There is, therefore, a need for a sterilization method other than autoclaving, ie a process that results in significant changes in soil properties, thus helping to increase the chemical reduction of triphenyltetrazolium chloride.

  1. Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci

    Directory of Open Access Journals (Sweden)

    Guillermo Hugo Peralta

    Full Text Available ABSTRACT Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.

  2. [Informatics analysis of malate dehydrogenase from Taenia saginata asiatica].

    Science.gov (United States)

    Huang, Jiang; Hu, Xu-Chu; Huang, Yan; Yu, Xin-Bing; Bao, Huai-En; Lang, Shu-Yuan; Liao, Xing-Jiang

    2008-06-30

    Tools from bioinformatics websites such as NCBI, ExPaSy were used for the analysis. The malate dehydrogenase full-length gene from Taenia saginata asiatica was 1 212 bp in length, with a coding region of 30-1 028 bp and coding 332 amino acids. It was a complete and full-length gene compared with the homologues in GenBank. The protein showed no transmembrane region, with stable physical-chemical characteristics. Three major linear epitopes located aa95-aa100, aa322-aa327 and aa117-aa122, with certain distance from each other on the surface of spatial structure of malate dehydrogenase (MDH). The last one was the linear epitope of Taenia. This cytosolic malate dehydrogenase gene is a potential antigen for diagnosis.

  3. Article Commentary: The Pivotal Role of Aldehyde Toxicity in Autism Spectrum Disorder: The Therapeutic Potential of Micronutrient Supplementation

    Directory of Open Access Journals (Sweden)

    Frances Jurnak

    2015-01-01

    Full Text Available Autism spectrum disorder (ASD is characterized by social and communication impairments as well as by restricted, repetitive patterns of behavior and interests. Genomic studies have not revealed dominant genetic errors common to all forms of ASD. So ASD is assumed to be a complex disorder due to mutations in hundreds of common variants. Other theories argue that spontaneous DNA mutations and/or environmental factors contribute to as much as 50% of ASD. In reviewing potential genetic linkages between autism and alcoholism, it became apparent that all theories of ASD are consistent with aldehyde toxicity, in which endogenous and exogenous aldehydes accumulate as a consequence of mutations in key enzymes. Aldehyde toxicity is characterized by cell-localized, micronutrient deficiencies in sulfur-containing antioxidants, thiamine (B1, pyridoxine (B6, folate, Zn 2+ , possibly Mg 2+ , and retinoic acid, causing oxidative stress and a cascade of metabolic disturbances. Aldehydes also react with selective cytosolic and membrane proteins in the cell of origin; then some types migrate to damage neighboring cells. Reactive aldehydes also form adducts with DNA, selectively mutating bases and inducing strand breakage. This article reviews the relevant genomic, biochemical, and nutritional literature, which supports the central hypothesis that most ASD symptoms are consistent with symptoms of aldehyde toxicity. The hypothesis represents a paradigm shift in thinking and has profound implications for clinical detection, treatment, and even prevention of ASD. Insight is offered as to which neurologically afflicted children might successfully be treated with micronutrients and which children are unlikely to be helped. The aldehyde toxicity hypothesis likely applies to other neurological disorders.

  4. Crystal structure of homoisocitrate dehydrogenase from Schizosaccharomyces pombe

    Energy Technology Data Exchange (ETDEWEB)

    Bulfer, Stacie L.; Hendershot, Jenna M.; Trievel, Raymond C. (Michigan); (UCSF)

    2013-09-18

    Lysine biosynthesis in fungi, euglena, and certain archaebacteria occurs through the {alpha}-aminoadipate pathway. Enzymes in the first steps of this pathway have been proposed as potential targets for the development of antifungal therapies, as they are absent in animals but are conserved in several pathogenic fungi species, including Candida, Cryptococcus, and Aspergillus. One potential antifungal target in the {alpha}-aminoadipate pathway is the third enzyme in the pathway, homoisocitrate dehydrogenase (HICDH), which catalyzes the divalent metal-dependent conversion of homoisocitrate to 2-oxoadipate (2-OA) using nicotinamide adenine dinucleotide (NAD{sup +}) as a cofactor. HICDH belogns to a family of {beta}-hydroxyacid oxidative decarboxylases that includes malate dehydrogenase, tartrate dehydrogenase, 6-phosphogluconate dehydrogenase, isocitrate dehydrogenase (ICDH), and 3-isopropylmalte dehydrogenase (IPMDH). ICDH and IPMDH are well-characterized enzymes that catalyze the decarboxylation of isocitrate to yield 2-oxoglutarate (2-OG) in the citric acid cycle and the conversion of 3-isopropylmalate to 2-oxoisovalerate in the leucine biosynthetic pathway, respectively. Recent structural and biochemical studies of HICDH reveal that this enzyme shares sequence, structural, and mechanistic homology with ICDH and IPMDH. To date, the only published structures of HICDH are from the archaebacteria Thermus thermophilus (TtHICDH). Fungal HICDHs diverge from TtHICDH in several aspects, including their thermal stability, oligomerization state, and substrate specificity, thus warranting further characterization. To gain insights into these differences, they determined crystal structures of a fungal Schizosaccharomyces pombe HICDH (SpHICDH) as an apoenzyme and as a binary complex with additive tripeptide glycyl-glycyl-glycine (GGG) to 1.55 {angstrom} and 1.85 {angstrom} resolution, respectively. Finally, a comparison of the SpHICDH and TtHICDH structures reveal differences in

  5. Screening of Glucose-6-Phosphate Dehydrogenase Deficiency in Cord Blood

    Directory of Open Access Journals (Sweden)

    Can Acipayam

    2014-02-01

    Aim: Glucose-6-phosphate dehydrogenase deficiency is an important factor in etiology of pathologic neonatal jaundice. The aim of this study was to indicate the significance of screening glucose-6-phosphate dehydrogenase deficiency in the cord blood of neonates and the frequency of this deficiency in the etiology of neonatal hyperbilirubinemia. Material and Method: The study was performed consecutive 1015 neonates were included. Five hundred fifty six (54.8% of them were male and 459 (45.2% were female. The following parameters were recorded: Gender, birth weight, birth height, head circumference and gestational age. The glucose-6-phosphate dehydrogenase level of neonates were measured with quantitative method in cord blood. Also, hemoglobine, hematocrite, red blood cell count and blood group were measured. The following parameters were recorded in cases with jaundice: exchange transfusion, phototherapy, physiologic and pathologic jaundice, peak bilirubin day, maximum bilirubin level, total bilirubin level at the first day of jaundice, beginning time of jaundice. Results: Enzyme deficiency was detected in 133 (13.1% of neonates and 76 (57% of them were male, 57 (43% were female. Significant difference was detected in low glucose-6-phosphate dehydrogenase enzyme level with jaundice group for total bilirubin level at the first day of jaundice, maximum total bilirubin level and pathologic jaundice (p<0.05. Discussion: The ratio of glucose-6-phosphate dehydrogenase deficiency was found in Edirne in this study and this ratio was higher than other studies conducted in our country. For this reason, glucose-6-phosphate dehydrogenase enzyme level in cord blood of neonates should be measured routinely and high risk neonates should be followed up for hyperbilirubinemia and parents should be informed in our region.

  6. Reversible inactivation of CO dehydrogenase with thiol compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kreß, Oliver [Department of Microbiology, University of Bayreuth, 95440 Bayreuth (Germany); Gnida, Manuel [Department of Chemistry, University of Paderborn, 33098 Paderborn (Germany); Pelzmann, Astrid M. [Department of Microbiology, University of Bayreuth, 95440 Bayreuth (Germany); Marx, Christian [Institute of Biochemistry and Biophysics, Friedrich-Schiller-University of Jena, 07745 Jena (Germany); Meyer-Klaucke, Wolfram [Department of Chemistry, University of Paderborn, 33098 Paderborn (Germany); Meyer, Ortwin, E-mail: Ortwin.Meyer@uni-bayreuth.de [Department of Microbiology, University of Bayreuth, 95440 Bayreuth (Germany)

    2014-05-09

    Highlights: • Rather large thiols (e.g. coenzyme A) can reach the active site of CO dehydrogenase. • CO- and H{sub 2}-oxidizing activity of CO dehydrogenase is inhibited by thiols. • Inhibition by thiols was reversed by CO or upon lowering the thiol concentration. • Thiols coordinate the Cu ion in the [CuSMo(=O)OH] active site as a third ligand. - Abstract: Carbon monoxide dehydrogenase (CO dehydrogenase) from Oligotropha carboxidovorans is a structurally characterized member of the molybdenum hydroxylase enzyme family. It catalyzes the oxidation of CO (CO + H{sub 2}O → CO{sub 2} + 2e{sup −} + 2H{sup +}) which proceeds at a unique [CuSMo(=O)OH] metal cluster. Because of changing activities of CO dehydrogenase, particularly in subcellular fractions, we speculated whether the enzyme would be subject to regulation by thiols (RSH). Here we establish inhibition of CO dehydrogenase by thiols and report the corresponding K{sub i}-values (mM): L-cysteine (5.2), D-cysteine (9.7), N-acetyl-L-cysteine (8.2), D,L-homocysteine (25.8), L-cysteine–glycine (2.0), dithiothreitol (4.1), coenzyme A (8.3), and 2-mercaptoethanol (9.3). Inhibition of the enzyme was reversed by CO or upon lowering the thiol concentration. Electron paramagnetic resonance spectroscopy (EPR) and X-ray absorption spectroscopy (XAS) of thiol-inhibited CO dehydrogenase revealed a bimetallic site in which the RSH coordinates to the Cu-ion as a third ligand ([Mo{sup VI}(=O)OH{sub (2)}SCu{sup I}(SR)S-Cys]) leaving the redox state of the Cu(I) and the Mo(VI) unchanged. Collectively, our findings establish a regulation of CO dehydrogenase activity by thiols in vitro. They also corroborate the hypothesis that CO interacts with the Cu-ion first. The result that thiol compounds much larger than CO can freely travel through the substrate channel leading to the bimetallic cluster challenges previous concepts involving chaperone function and is of importance for an understanding how the sulfuration step in

  7. HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY FOR DETERMINATION OF AROMATIC ALDEHYDES IN WINE DISTILLATES

    Directory of Open Access Journals (Sweden)

    Elena Nezalzova

    2011-06-01

    Full Text Available Quality control of alcoholic beverages, coming into the market, is a defining element in preventing the production and supplying of defective products. One of the main criteria for quality control of wine distillates is to estimate their age, and more precisely the period of maturation as the dominant factor in determining the quality of cognacs and, consequently, their market price. On the opinion of majority scientists, one of the main factors, which determines the age of wine distillates, is the content of aromatic aldehydes, mostly vanillin, and their ratio.

  8. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    Science.gov (United States)

    Smith, R.E.; Dolbeare, F.A.

    1980-10-21

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes. No Drawings

  9. Reactions of CH-acids with α,β-unsaturated aldehydes in ionic liquids

    DEFF Research Database (Denmark)

    Kryshtal, G. V.; Zhdankina, G. M.; Astakhova, Irina Kira

    2004-01-01

    Metal carbonate-catalyzed reactions of CH-acids (diethyl malonate, ethyl acetoacetate, ethyl cyanoacetate, and ethyl 2-acetyl- and 2-ethoxycarbonyl-5,9- dimethyldeca-4,8-dienoates) with α,β-unsaturated aldehydes (acrolein, crotonaldehyde, citral) were studied in an ionic liquid, 1-butyl-3......- methylimidazolium hexafluorophosphate [bmim][PF 6], and in a 1-butyl-3-methylimidazolium bromide ([bmim][Br]) - benzene system. The reactions with acrolein and crotonaldehyde afforded Michael addition products, those with citral resulted in Knoevenagel addition products. Sonication increased the yields...

  10. Structure of products of the condensation of α,β-unsaturated aldehydes with dimedone

    International Nuclear Information System (INIS)

    Yurchenko, O.I.; Pushkareva, K.S.; Zheldubovskaya, G.A.; Komarov, N.V.; Berkova, G.A.

    1987-01-01

    α,β-Acetylenic aldehydes and cinnamaldehyde in reaction with dimedone give the corresponding unsaturated bis(dimedonyl)methanes. In the case of acrolein and crotonaldehyde intramolecular cyclization occurs with the participation of hydroxyl of the dimedone fragment and the double bond with the formation of pyran systems. The PMR spectra were determined on Tesla BS-487C (80 MHz) and Tesla BS-467C (60 MHz) spectrometers in chloroform-d, pyridine-d 5 , and trifluoroacetic acid solutions. Internal standards HMDS and methylene chloride

  11. Revisiting the Reaction Between Diaminomaleonitrile and Aromatic Aldehydes: a Green Chemistry Approach

    Directory of Open Access Journals (Sweden)

    Francisco León

    2006-11-01

    Full Text Available The reaction between diaminomaleonitrile (DAMN and aldehydes and the resulting monoimines are well known. Since the standard reaction conditions involve the use of toxic solvents (typically methanol, we have sought to apply green chemistry principles to this reaction by either using water as the solvent without any catalysts or employing “solvent-free” conditions. The monoimines derived from DAMN are of interest as precursors for obtaining different heterocyclic systems and linear polymers. The methodologies used have significant advantages with regards to cost and environmental considerations.

  12. Merging Photoredox Catalysis with Organocatalysis: The Direct Asymmetric Alkylation of Aldehydes

    Science.gov (United States)

    Nicewicz, David A.; MacMilla, David W. C.

    2009-01-01

    Photoredox catalysis and organocatalysis represent two powerful fields of molecule activation that have found widespread application in the areas of inorganic and organic chemistry, respectively. We merged these two catalysis fields to solve problems in asymmetric chemical synthesis. Specifically, the enantioselective intermolecular α-alkylation of aldehydes has been accomplished using an interwoven activation pathway that combines both the photoredox catalyst Ru(bpy)3Cl2 (where bpy is 2,2′-bipyridine) and an imidazolidinone organocatalyst. This broadly applicable, yet previously elusive, alkylation reaction is now highly enantioselective and operationally trivial. PMID:18772399

  13. 4-metalated condensed pyrimidines: their preparation and reaction with aldehydes under Barbier-type conditions.

    Science.gov (United States)

    Therkelsen, Frans D; Rottländer, Mario; Thorup, Niels; Pedersen, Erik Bjerregaard

    2004-06-10

    [reaction: see text] The organometallic intermediate obtained from halogen-metal exchanges of 4-iodo-6-phenylthieno[2,3-d]pyrimidine under Barbier-type conditions was reacted with aldehydes to form the corresponding alcohols in moderate yields. The reaction involving an organolithium intermediate proceeded only at low temperature, whereas the reaction involving a magnesium ate intermediate also proceeded at room temperature. A crystal structure confirms that the expected constitutional alcohol isomer is formed, where no migration has taken place. The conditions were also suitable for 9-benzyl-6-iodopurine.

  14. Merging photoredox catalysis with organocatalysis: the direct asymmetric alkylation of aldehydes.

    Science.gov (United States)

    Nicewicz, David A; MacMillan, David W C

    2008-10-03

    Photoredox catalysis and organocatalysis represent two powerful fields of molecule activation that have found widespread application in the areas of inorganic and organic chemistry, respectively. We merged these two catalysis fields to solve problems in asymmetric chemical synthesis. Specifically, the enantioselective intermolecular alpha-alkylation of aldehydes has been accomplished using an interwoven activation pathway that combines both the photoredox catalyst Ru(bpy)3Cl2 (where bpy is 2,2'-bipyridine) and an imidazolidinone organocatalyst. This broadly applicable, yet previously elusive, alkylation reaction is now highly enantioselective and operationally trivial.

  15. "Juice Monsters": Sub-Ohm Vaping and Toxic Volatile Aldehyde Emissions.

    Science.gov (United States)

    Talih, Soha; Salman, Rola; Karaoghlanian, Nareg; El-Hellani, Ahmad; Saliba, Najat; Eissenberg, Thomas; Shihadeh, Alan

    2017-10-16

    An emerging category of electronic cigarettes (ECIGs) is sub-Ohm devices (SODs) that operate at ten or more times the power of conventional ECIGs. Because carcinogenic volatile aldehyde (VA) emissions increase sharply with power, SODs may expose users to greater VAs. In this study, we compared VA emissions from several SODs and found that across device, VAs and power were uncorrelated unless power was normalized by coil surface area. VA emissions and liquid consumed were correlated highly. Analyzed in light of EU regulations limiting ECIG liquid nicotine concentration, these findings suggest potential regulatory levers and pitfalls for protecting public health.

  16. Rationalization of an unusual solvent-induced inversion of enantiomeric excess in organocatalytic selenylation of aldehydes.

    Science.gov (United States)

    Burés, Jordi; Dingwall, Paul; Armstrong, Alan; Blackmond, Donna G

    2014-08-11

    An unusual solvent-induced inversion of the sense of enantioselectivity observed in the α-selenylation of aldehydes catalyzed by a diphenylprolinol silyl ether catalyst is correlated to the presence of intermediates formed subsequent to the highly selective C-Se bond-forming step in the catalytic cycle. This work provides support for a mechanistic concept for enamine catalysis and includes a general role for "downstream intermediates" in selectivity outcomes in organocatalysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Stereochemistry and synthetic applications of products of fermentation of alpha,beta-unsaturated aromatic aldehydes by baker's yeast.

    Science.gov (United States)

    Fuganti, C; Grasselli, P

    1985-01-01

    Baker's yeast fermenting on D-glucose converts 2-substituted C6-C3 alpha,beta-unsaturated aromatic aldehydes into the corresponding 3-phenylprop-2-en-1-ols and 3-phenylpropan-1-ols, and into the 4-substituted (2S,3R)-5-phenylpent-4-en-2,3-ols. The formation of the C6-C3 alcohols from the aldehydes by baker's yeast was already known, but the production of the methyl diols is new. The conversion of C6-C3 alpha,beta-unsaturated aldehydes into the C6-C5 methyl diols can be viewed as the overall consequence of two distinct chemical operations: (1) addition of a C2 unit equivalent to acetaldehyde onto the Si-face of the carbonyl carbon of the unsaturated aldehyde forms the (R)-alpha-hydroxy ketone in an acyloin-type condensation, and (2) reduction of this intermediate on the Re-face of the carbonyl gives the diol actually isolated. There is some tolerance by the enzymic system(s) involved in the reaction(s) leading from the C6-C3 alpha,beta-unsaturated aromatic aldehydes to the 4-substituted (2S,3R)-5-phenylpent-4-en-2,3-ols as far as the structure of the aromatic aldehydes and the substitutents in the alpha position are concerned, but acetaldehyde is the only aldehyde accepted as second terminus of the reaction. However, synthetic alpha-hydroxy ketones, prepared from aldehydes that cannot be directly converted by yeast into the corresponding methyl diols, are reduced by yeast. This indicates that the reason direct conversion of the aldehydes does not occur is that these materials probably cannot be accepted as substrates by the condensing enzyme(s). The (2S,3R)-diols can be used instead of natural carbohydrates as starting materials for the synthesis of optically active forms of natural products belonging to different structural classes. Applications of these diols in the synthesis of L-daunosamine, the natural form of vitamin E and other products are discussed.

  18. Assay of partially purified glutamate dehydrogenase isolated from ...

    African Journals Online (AJOL)

    Glutamate dehydrogenase (E C 1.4.1.1) isolated from the seeds of asparagus beans was partially purified to a factor of 22 by dialysis after fractional precipitation with solid ammonium sulphate at 40 and 60% saturation. A specific activity of 11.78μmol min-1 mg-1 protein was calculated for the partially purified enzyme when ...

  19. 21 CFR 862.1440 - Lactate dehydrogenase test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lactate dehydrogenase test system. 862.1440 Section 862.1440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test...

  20. 21 CFR 862.1420 - Isocitric dehydrogenase test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Isocitric dehydrogenase test system. 862.1420 Section 862.1420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test...

  1. New enzymatic assay, parasite lactate dehydrogenase in diagnosis ...

    African Journals Online (AJOL)

    Background: The unique ability of plasmodial lactate dehydrogenase p(LDH) to utilise 3-acetyl pyridine dinucleotide (APAD) in lieu of NAD as a coenzyme in the conversion of pyruvate to lactate, led to the development of a biochemical assay for the detection of plasmodial parasitaemia. Researchers have reported that ...

  2. Crystallization behaviour of glyceraldehyde dehydrogenase from Thermoplasma acidophilum

    Czech Academy of Sciences Publication Activity Database

    Lermark, L.; Degtjarik, Oksana; Steffler, F.; Sieber, V.; Kutá-Smatanová, Ivana

    2015-01-01

    Roč. 71, č. 12 (2015), s. 1475-1480 ISSN 2053-230X Institutional support: RVO:67179843 Keywords : TaAlDH * Thermoplasma acidophilum * bioproduction * cell-free enzyme cascade * glyceraldehyde dehydrogenase Subject RIV: CE - Biochemistry Impact factor: 0.647, year: 2015

  3. Novel thidiazuron-derived inhibitors of cytokinin oxidase/dehydrogenase

    Czech Academy of Sciences Publication Activity Database

    Nisler, Jaroslav; Kopečný, D.; Končitíková, R.; Zatloukal, Marek; Bazgier, Václav; Berka, K.; Zalabák, D.; Briozzo, P.; Strnad, Miroslav; Spíchal, Lukáš

    2016-01-01

    Roč. 92, 1-2 (2016), s. 235-248 ISSN 0167-4412 R&D Projects: GA MŠk(CZ) LO1204; GA ČR GA15-22322S Institutional support: RVO:61389030 Keywords : Cytokinin oxidase/dehydrogenase * Crystal structure * Molecular docking Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.356, year: 2016

  4. Cloning and expression of chicken 20-hydroxysteroid dehydrogenase

    Czech Academy of Sciences Publication Activity Database

    Bryndová, Jana; Klusoňová, Petra; Kučka, Marek; Vagnerová, Karla; Mikšík, Ivan; Pácha, Jiří

    2006-01-01

    Roč. 37, č. 3 (2006), s. 453-462 ISSN 0952-5041 R&D Projects: GA AV ČR(CZ) IAA6011201 Grant - others:GA UK(CZ) 216/2004 Institutional research plan: CEZ:AV0Z50110509 Keywords : 20-hydroxysteroid dehydrogenase * SDR family Subject RIV: CE - Biochemistry Impact factor: 2.988, year: 2006

  5. Glucose-6-phosphate dehydrogenase deficiency; the single most ...

    African Journals Online (AJOL)

    Introduction: Glucose- 6-phosphate dehydrogenase deficiency is the most common enzymatic disorder of the red cell and an important risk factor for neonatal jaundice. Methodology: The aim of the study was to determine the incidence of G-6-PD deficiency among jaundiced neonates, and describe the associated morbidity ...

  6. Studies on the structure and function of pyruvate dehydrogenase complexes

    NARCIS (Netherlands)

    Abreu, de R.

    1978-01-01

    The aim of the present investigation was to obtain more information of the structure and function of the pyruvate dehydrogenase complexes from Azotobacter vinelandii and Escherichia coli.

    In chapter 2 a survey is given of the recent literature on

  7. Prevalence of glucose-6-phosphate dehydrogenase deficiency in ...

    African Journals Online (AJOL)

    Pradeep Kumar

    2016-02-06

    Feb 6, 2016 ... Meta-analysis;. Prevalence. Abstract Background: Glucose-6-phosphate dehydrogenase (G6PD) is a house keeping enzyme which catalyzes the first step in the hexose monophosphate pathway of glucose metabolism. G6PD deficiency is the commonest hemolytic X-linked genetic disease, which affects ...

  8. Alcohol consumption, alcohol dehydrogenase 3 polymorphism, and colorectal adenomas

    NARCIS (Netherlands)

    Tiemersma, E.W.; Wark, P.A.; Ocké, M.C.; Bunschoten, A.; Otten, M.H.; Kok, F.J.; Kampman, E.

    2003-01-01

    Alcohol is a probable risk factor with regard to colorectal neoplasm and is metabolized to the carcinogen acetaldehyde by the genetically polymorphic alcohol dehydrogenase 3 (ADH3) enzyme. We evaluated whether the association between alcohol and colorectal adenomas is modified by ADH3 polymorphism.

  9. Perioperative care of an infant with pyruvate dehydrogenase ...

    African Journals Online (AJOL)

    The authors present the anaesthetic management of two infants with pyruvate dehydrogenase complex deficiency (PDCD), a rare genetic disorder of carbohydrate metabolism leading to lactic acidosis and neurological impairment. In the first case, a seven-month-old infant, undergoing closed reduction of a dislocated hip, ...

  10. Substrate Specificity via Ternary Complex Formation with Glutamate Dehydrogenase

    NARCIS (Netherlands)

    Koekoek, Henk; Robillard, George T.

    1977-01-01

    Very little discrimination is observed in the binary binding of dicarboxylic acid substrate analogues to glutamate dehydrogenase as monitored by proton nuclear magnetic resonance. Variation in length, charge, bulkiness and conformational rigidity resulted in only a factor of five variation in KD and

  11. Isolation and characterization of the rat gene encoding glutamate dehydrogenase

    NARCIS (Netherlands)

    Das, A. T.; Arnberg, A. C.; Malingré, H.; Moerer, P.; Charles, R.; Moorman, A. F.; Lamers, W. H.

    1993-01-01

    The concentration of glutamate dehydrogenase (GDH) varies strongly between different organs and between different regions within organs. To permit further studies on the regulation of GDH expression, we isolated and characterized the rat gene encoding the GDH protein. This gene contains 13 exons and

  12. Overexpression of 11β-hydroxysteroid dehydrogenase 1 in visceral ...

    African Journals Online (AJOL)

    Ibrahim Eldaghayes

    2018-02-23

    Feb 23, 2018 ... Alterations in this enzyme are related to the development of metabolic syndrome, obesity and hyperadrenocorticism. (HAC). ..... 11β-hydroxysteroid dehydrogenase type 1 in visceral adipose tissue and portal hypercortisolism in non-alcoholic fatty liver disease. Liver Int. 32(3), 392-399. Carroll, B.J., Cassidy ...

  13. Assessment of the activity of glucose-6-phosphate dehydrogenase ...

    African Journals Online (AJOL)

    Glucose-6-phosphate dehydrogenase (G-6-PD) is an enzyme in the pentose phosphate pathway (PPP) which reduces NADP to NADPH while oxidizing glucose-6-phosphate. In turn, NADPH then provides reducing equivalents needed for the conversion of oxidized glutathione to reduced glutathione, which protects against ...

  14. Characterization of the L-lactate dehydrogenase from Aggregatibacter actinomycetemcomitans.

    Directory of Open Access Journals (Sweden)

    Stacie A Brown

    Full Text Available Aggregatibacter actinomycetemcomitans is a Gram-negative opportunistic pathogen and the proposed causative agent of localized aggressive periodontitis. A. actinomycetemcomitans is found exclusively in the mammalian oral cavity in the space between the gums and the teeth known as the gingival crevice. Many bacterial species reside in this environment where competition for carbon is high. A. actinomycetemcomitans utilizes a unique carbon resource partitioning system whereby the presence of L-lactate inhibits uptake of glucose, thus allowing preferential catabolism of L-lactate. Although the mechanism for this process is not fully elucidated, we previously demonstrated that high levels of intracellular pyruvate are critical for L-lactate preference. As the first step in L-lactate catabolism is conversion of L-lactate to pyruvate by lactate dehydrogenase, we proposed a model in which the A. actinomycetemcomitans L-lactate dehydrogenase, unlike homologous enzymes, is not feedback inhibited by pyruvate. This lack of feedback inhibition allows intracellular pyruvate to rise to levels sufficient to inhibit glucose uptake in other bacteria. In the present study, the A. actinomycetemcomitans L-lactate dehydrogenase was purified and shown to convert L-lactate, but not D-lactate, to pyruvate with a K(m of approximately 150 microM. Inhibition studies reveal that pyruvate is a poor inhibitor of L-lactate dehydrogenase activity, providing mechanistic insight into L-lactate preference in A. actinomycetemcomitans.

  15. Assessment of creatine kinase and lactate dehydrogenase activities ...

    African Journals Online (AJOL)

    Ina bid to investigate the influence of menopausal on coronary heart disease, plasma creatine kinase (CK) and lactate dehydrogenase (LDH) enzymes were analysed on a prospective cohort of 100 women attending Irrua Specialist Teaching Hospital (ISTH), Irrua, Edo state-Nigeria. They were divided into two groups; ...

  16. Properties of glucoside 3-dehydrogenase and its potential applications

    African Journals Online (AJOL)

    These 3-ketoglucosides are useful as building blocks for chemicals such as detergents and polymers. The versatile glucoside 3-dehydrogenase has potential applications in different fields including sugar industry, clinical diagnosis and pharmaceutical intermediates synthesis. This review attempts to describe the glucoside ...

  17. Cloning and in silico analysis of a cinnamyl alcohol dehydrogenase ...

    Indian Academy of Sciences (India)

    Lignin is a major constituent of plant cell walls and indispensable to the normal growth of a plant. However, the presence of lignin complicates the structure of the plant cell walls and negatively influences pulping industry, lignocellulose utilization as well as forage properties. Cinnamyl alcohol dehydrogenase (CAD), a key ...

  18. Efficiency of superoxide anions in the inactivation of selected dehydrogenases

    International Nuclear Information System (INIS)

    Rodacka, Aleksandra; Serafin, Eligiusz; Puchala, Mieczyslaw

    2010-01-01

    The most ubiquitous of the primary reactive oxygen species, formed in all aerobes, is the superoxide free radical. It is believed that the superoxide anion radical shows low reactivity and in oxidative stress it is regarded mainly as an initiator of more reactive species such as · OH and ONOO - . In this paper, the effectiveness of inactivation of selected enzymes by radiation-generated superoxide radicals in comparison with the effectiveness of the other products of water radiolysis is examined. We investigate three enzymes: glyceraldehyde-3-phosphate dehydrogenase (GAPDH), alcohol dehydrogenase (ADH) and lactate dehydrogenase (LDH). We show that the direct contribution of the superoxide anion radical to GAPDH and ADH inactivation is significant. The effectiveness of the superoxide anion in the inactivation of GAPDH and ADG was only 2.4 and 2.8 times smaller, respectively, in comparison with hydroxyl radical. LDH was practically not inactivated by the superoxide anion. Despite the fact that the studied dehydrogenases belong to the same class of enzymes (oxidoreductases), all have a similar molecular weight and are tetramers, their susceptibility to free-radical damage varies. The differences in the radiosensitivity of the enzymes are not determined by the basic structural parameters analyzed. A significant role in inactivation susceptibility is played by the type of amino acid residues and their localization within enzyme molecules.

  19. Efficiency of superoxide anions in the inactivation of selected dehydrogenases

    Energy Technology Data Exchange (ETDEWEB)

    Rodacka, Aleksandra, E-mail: olakow@biol.uni.lodz.p [Department of Molecular Biophysics, University of Lodz, Banacha 12/16, 90-237 Lodz (Poland); Serafin, Eligiusz, E-mail: serafin@biol.uni.lodz.p [Laboratory of Computer and Analytical Techniques, University of Lodz, Banacha 12/16, 90-237 Lodz (Poland); Puchala, Mieczyslaw, E-mail: puchala@biol.uni.lodz.p [Department of Molecular Biophysics, University of Lodz, Banacha 12/16, 90-237 Lodz (Poland)

    2010-09-15

    The most ubiquitous of the primary reactive oxygen species, formed in all aerobes, is the superoxide free radical. It is believed that the superoxide anion radical shows low reactivity and in oxidative stress it is regarded mainly as an initiator of more reactive species such as {sup {center_dot}}OH and ONOO{sup -}. In this paper, the effectiveness of inactivation of selected enzymes by radiation-generated superoxide radicals in comparison with the effectiveness of the other products of water radiolysis is examined. We investigate three enzymes: glyceraldehyde-3-phosphate dehydrogenase (GAPDH), alcohol dehydrogenase (ADH) and lactate dehydrogenase (LDH). We show that the direct contribution of the superoxide anion radical to GAPDH and ADH inactivation is significant. The effectiveness of the superoxide anion in the inactivation of GAPDH and ADG was only 2.4 and 2.8 times smaller, respectively, in comparison with hydroxyl radical. LDH was practically not inactivated by the superoxide anion. Despite the fact that the studied dehydrogenases belong to the same class of enzymes (oxidoreductases), all have a similar molecular weight and are tetramers, their susceptibility to free-radical damage varies. The differences in the radiosensitivity of the enzymes are not determined by the basic structural parameters analyzed. A significant role in inactivation susceptibility is played by the type of amino acid residues and their localization within enzyme molecules.

  20. Natural history of succinic semialdehyde dehydrogenase deficiency through adulthood

    NARCIS (Netherlands)

    Lapalme-Remis, S.; Lewis, E.C.; De Meulemeester, C.; Chakraborty, P.; Gibson, K.M.; Torres, C.; Guberman, A.; Salomons, G.; Jakobs, C.; Ali-Ridha, A.; Parviz, M.; Pearl, P.L.

    2015-01-01

    Objective: The natural history of succinic semialdehyde dehydrogenase (SSADH) deficiency in adulthood is unknown; we elucidate the clinical manifestations of the disease later in life. Methods: A 63-year-old man with long-standing intellectual disability was diagnosed with SSADH deficiency following

  1. Prevalence of glucose-6-phosphate dehydrogenase deficiency in ...

    African Journals Online (AJOL)

    Background: Glucose-6-phosphate dehydrogenase (G6PD) is a house keeping enzyme which catalyzes the first step in the hexose monophosphate pathway of glucose metabolism. G6PD deficiency is the commonest hemolytic X-linked genetic disease, which affects approximately 400 million people worldwide.

  2. Histochemistry and cytochemistry of glucose-6-phosphate dehydrogenase

    NARCIS (Netherlands)

    van Noorden, C. J.

    1984-01-01

    Histochemistry and cytochemistry of glucose-6-phosphate dehydrogenase has found many applications in biomedical research. However, up to several years ago, the methods used often appeared to be unreliable because many artefacts occurred during processing and staining of tissue sections or cells. The

  3. Serum creatine kinase and lactate dehydrogenase activities in ...

    African Journals Online (AJOL)

    P = 0.002). Conclusion: The significant elevation in serum CK and LDH activities indicates that these can be used as parameters for screening hypothyroid patients but not hyperthyroid patients. Key words: Hyperthyroidism, hypothyroidism, lactate dehydrogenase, serum creatine kinase. Date of Acceptance: 28-Aug-2011.

  4. Cloning and in silico analysis of a cinnamyl alcohol dehydrogenase ...

    Indian Academy of Sciences (India)

    2014-04-16

    Apr 16, 2014 ... 1992; Kim et al. 2004), the relationship between CAD genes and their functions was of great impor- tance. Since the important role in regulation of lignin con- tent and composition, more and more CAD genes and their. Keywords. lignin biosynthesis; cinnamyl alcohol dehydrogenase; clone; in silico analysis ...

  5. Glucose-6-phosphate dehydrogenase deficiency in northern Mexico ...

    Indian Academy of Sciences (India)

    Abstract. Glucose-6-phosphate dehydrogenase deficiency (G6PD) is the most common enzyme pathology in humans; it is X-linked inherited and causes neonatal hyperbilirubinaemia, chronic nonspherocytic haemolytic anaemia and drug-induced acute haemolytic anaemia. G6PD deficiency has scarcely been studied in ...

  6. Pyranose dehydrogenases: biochemical features and perspectives of technological applications

    Czech Academy of Sciences Publication Activity Database

    Peterbauer, C.; Volc, Jindřich

    2010-01-01

    Roč. 85, č. 4 (2010), s. 837-848 ISSN 0175-7598 Institutional research plan: CEZ:AV0Z50200510 Keywords : Pyranose dehydrogenase * Sugar oxidoreductase * Regioselectivity Subject RIV: EE - Microbiology, Virology Impact factor: 3.280, year: 2010

  7. Identification of glucose 6 phosphate dehydrogenase mutations by ...

    African Journals Online (AJOL)

    Identification of glucose 6 phosphate dehydrogenase mutations by single strand conformation polymorphism and gene sequencing analysis. ... Subject: Six DNA samples from Turkish males confirmed to have G-6-PD deficiency where available for the study. Results: One subject was found to have an abnormal mobility shift ...

  8. Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency in patients ...

    African Journals Online (AJOL)

    This is a study of Glucose-6-phosphate dehydrogenase(G6PD) deficiency in sickle cell anaemia patients attending the haematology clinic of the Jos University Teaching Hospital (JUTH), Jos- Nigeria. The prevalence of G6PD deficiency among the 130 sickle cell anaemia patients studied was found to be 18.5%. G6PD ...

  9. Eniluracil treatment completely inactivates dihydropyrimidine dehydrogenase in colorectal tumors

    NARCIS (Netherlands)

    Ahmed, F. Y.; Johnston, S. J.; Cassidy, J.; O'Kelly, T.; Binnie, N.; Murray, G. I.; van Gennip, A. H.; Abeling, N. G.; Knight, S.; McLeod, H. L.

    1999-01-01

    To determine the effect of eniluracil on colorectal tumor dihydropyrimidine dehydrogenase (DPD) activity. Patients who were to undergo primary colorectal tumor resection received oral eniluracil 10 mg/m(2) twice daily for 3 days before surgery. Mononuclear cells were obtained before the start of

  10. X-irradiation effects on the activity of dehydrogenases in the cockroach, Periplaneta Americana L

    Energy Technology Data Exchange (ETDEWEB)

    Vijayalakshmi, S. (Sri Sathya Sai Inst. of Higher Learning, Anantpur (India))

    1984-05-01

    Sublethal dose of X-irradiation caused an early increase and subsequent normalization in succinate and lactate dehydrogenases of the cockroach, while lethal dose produced an irreversible fall in succinate dehydrogenase and a gradual elevation in lactate dehydrogenase at all post-irradiation periods studied, suggesting dose dependent impairment of aerobic and anaerobic pathways.

  11. Investigation of antimicrobial activities of indole-3-aldehyde hydrazide/hydrazone derivatives.

    Science.gov (United States)

    Gurkok, Gokce; Altanlar, Nurten; Suzen, Sibel

    2009-01-01

    Indoles and hydrazone-type compounds constitute an important class of compounds for new drug development in order to discover an effective compound against multi-drug-resistant microbial infections. A series of indole-3-aldehyde and 5-bromoindole-3-aldehyde hydrazide and hydrazones was evaluated for their in vitro antimicrobial activities using the 2-fold serial dilution technique against Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Escherichia coli, Bacillus subtilis and Candida albicans. The minimum inhibitory concentration (MIC) was determined for test compounds and for the reference standards sultamicillin, ampicillin, fluconazole and ciprofloxacin. Compounds possessed a broad spectrum of activity having MIC values of 6.25-100 mg/ml against the tested microorganisms. Compounds 1a-1j, in particular, displayed better activity against MSRA and significant activity against S. aureus relative to ampicillin. Unexpectedly, indole nicotinic acid hydrazides showed no significant activity while indole anisic acid hydrazides displayed better activity. The results may be instructive to researchers attempting to gain more understanding of the antimicrobial activity of indole hydrazide/hydrazone-type compounds. (c) 2008 S. Karger AG, Basel.

  12. Selective Production of Aromatic Aldehydes from Heavy Fraction of Bio-oil via Catalytic Oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yan; Chang, Jie; Ouyang, Yong; Zheng, Xianwei [South China Univ. of Technology, Guangzhou (China)

    2014-06-15

    High value-added aromatic aldehydes (e. g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide (H{sub 2}O{sub 2}) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin (Co(TPPS{sub 4})) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without Co(TPPS{sub 4}). Moreover, a possible mechanism of HFBO oxidation using Co(TPPS{sub 4})/H{sub 2}O{sub 2} was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under Co(TPPS{sub 4})/H{sub 2}O{sub 2} system.

  13. NMR analysis of aldehydes in Sicilian extra-virgin olive oils by DPFGSE techniques

    Directory of Open Access Journals (Sweden)

    Enrico Rotondo

    2011-03-01

    Full Text Available The DPFGSE NMR sequences open new perspectives in the volatile compounds analysis of food matrices. Many fresh extra-virgin Sicilian olive oils, analyzed by this technique, show two main resonances in the aldehydic spectral region (9–10 ppm, at 9.18 and 9.58 ppm. The former was never reported so far, the latter was sometime highlighted as a minor aldehydic component signal of spectra showing stronger resonances at 9.45 and 9.70 ppm. Thermal treatment at 220°C of extra virgin olive oil samples lead to the complete transformation of the resonances at 9.18 and 9.58 ppm into those at 9.45 and 9.70 ppm in 50 minutes. Analogous transformation takes place place in CDCl3 at rt in several weeks. These results suggest the transformation of relatively unstable compounds into thermodynamically more stable products whose resonances are commonly reported in the literature. Even though these chemical changes involve minimal amount of product, they are of crucial importance to define: i organoleptic extra virgin olive oil properties; ii fraudulent chemical or thermal treatment detection; iii extra virgin oil ageing.

  14. The use of aldehyde indicators to determine glutaraldehyde and alkaline glutaraldehyde contamination in chemical protective gloves.

    Science.gov (United States)

    Vo, Evanly; Zhuang, Zhenzhen

    2009-07-01

    The aim of this study was to assess the use of aldehyde indicator pads for detection of glutaraldehyde and alkaline glutaraldehyde permeation through chemical protective gloves under simulated in-use conditions. The quantitative analysis of glutaraldehyde permeation through a glove material was determined for Metricide, Wavicide, and 50% glutaraldehyde following a solvent-desorption process and gas chromatographic analysis. All glutaraldehyde solutions exhibited >99% adsorption (including both the glutaraldehyde oligomers of the reaction product and the excess glutaraldehyde) on the pads over the spiking range 0.05-5.0 microL. Breakthrough times for protective gloves were determined using the Thermo-Hand test method, and found to range from 76 to 150, from 170 to 230, and from 232 to 300 min for Metricide, Wavicide, and 50% glutaraldehyde, respectively. Glutaraldehyde recovery was calculated and ranged from 61 to 80% for all glutaraldehyde solutions. The mass of glutaraldehyde in these solutions at the time of breakthrough detection ranged from 17 to 18, from 18 to 19, and from 19 to 20 microg/cm(2) for Wavicide, 50% glutaraldehyde solution, and Metricide, respectively. Aldehyde indicator pads and the Thermo-Hand test method together should find utility in detecting, collecting, and quantitatively analyzing glutaraldehyde permeation samples through chemical protective gloves under simulated in-use conditions.

  15. Emissions of acrolein and other aldehydes from biodiesel-fueled heavy-duty vehicles.

    Science.gov (United States)

    Cahill, Thomas M; Okamoto, Robert A

    2012-08-07

    Aldehyde emissions were measured from two heavy-duty trucks, namely 2000 and 2008 model year vehicles meeting different EPA emission standards. The tests were conducted on a chassis dynamometer and emissions were collected from a constant volume dilution tunnel. For the 2000 model year vehicle, four different fuels were tested, namely California ultralow sulfur diesel (CARB ULSD), soy biodiesel, animal biodiesel, and renewable diesel. All of the fuels were tested with simulated city and high speed cruise drive cycles. For the 2008 vehicle, only soy biodiesel and CARB ULSD fuels were tested. The research objective was to compare aldehyde emission rates between (1) the test fuels, (2) the drive cycles, and (3) the engine technologies. The results showed that soy biodiesel had the highest acrolein emission rates while the renewable diesel showed the lowest. The drive cycle also affected emission rates with the cruise drive cycle having lower emissions than the urban drive cycle. Lastly, the newer vehicle with the diesel particulate filter had greatly reduced carbonyl emissions compared to the other vehicles, thus demonstrating that the engine technology had a greater influence on emission rates than the fuels.

  16. Curcumin loaded gum arabic aldehyde-gelatin nanogels for breast cancer therapy

    International Nuclear Information System (INIS)

    Sarika, P.R.; Nirmala, Rachel James

    2016-01-01

    Curcumin, a widely studied hydrophobic polyphenol with anticancer potential is loaded in gum arabic aldehyde-gelatin (GA Ald-Gel) nanogels to improve its bioavailability and therapeutic efficacy towards cancer cells. Physicochemical properties of the curcumin loaded GA Ald-Gel nanogels are investigated by different techniques including dynamic light scattering (DLS), NMR spectroscopy and scanning electron microscopy (SEM). These nanogels exhibit hydrodynamic diameter of 452 ± 8 nm with a zeta potential of − 27 mV. The nanogels possess an encapsulation efficiency of 65 ± 3%. Potential of the nanogels for controlled release of curcumin is illustrated by in vitro drug release studies. Hemocompatibility and cytocompatibility of the drug loaded nanogels are evaluated. In vitro cytotoxicity of the bare and curcumin loaded nanogels are analyzed by MTT assay towards MCF-7 cells. The results manifest that curcumin loaded nanogels induce toxicity in MCF-7 cells. Confocal laser scanning microscopy (CLSM) studies indicate in vitro cellular uptake of the nanogels in MCF-7 cells. All these results prove the suitability of the curcumin loaded GA Ald-Gel nanogels for cancer therapy. - Highlights: • Curcumin loaded gum arabic aldehyde-gelatin nanogels were prepared. • Nanogels maintained negative zeta potential after curcumin loading. • Curcumin release is higher at acidic pH compared to neutral pH. • Curcumin loaded GA Ald-Gel nanogels shows toxicity towards MCF-7 cells. • Green fluorescence in MCF-7 cells confirmed the intracellular uptake.

  17. Kinetic study of the gas-phase reaction of atomic chlorine with a series of aldehydes

    Directory of Open Access Journals (Sweden)

    D. Rodríguez

    2005-01-01

    Full Text Available The reactions of Cl atoms with a series of unsaturated aldehydes have been investigated for the first time using a relative method. In order to obtain additional information for a qualitative structure versus reactivity discussion, we have also determined the rate coefficients for the reactions of atomic chlorine with their respective saturated aldehydes. These relative measurements were performed at room temperature and atmospheric pressure of air and N2, by using ethane, propene and 1-butene as reference compounds. The weighted average relative rate constants obtained, kCl±2σ (in units of cm3 molecule−1 s−1 were: trans-2-pentenal (1.31±0.19×10−10; trans-2-hexenal (1.92±0.22×10−10; trans-2-heptenal (2.40±0.29×10−10; n-pentanal (2.56±0.27×10−10; n-hexanal (2.88±0.37×10−10; n-heptanal (3.00±0.34×10−10. Finally, results and atmospheric implications are discussed and compared with the reactivity with OH and NO3 radicals.

  18. Curcumin loaded gum arabic aldehyde-gelatin nanogels for breast cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sarika, P.R., E-mail: sarikapaithal@gmail.com; Nirmala, Rachel James, E-mail: nirmala@iist.ac.in

    2016-08-01

    Curcumin, a widely studied hydrophobic polyphenol with anticancer potential is loaded in gum arabic aldehyde-gelatin (GA Ald-Gel) nanogels to improve its bioavailability and therapeutic efficacy towards cancer cells. Physicochemical properties of the curcumin loaded GA Ald-Gel nanogels are investigated by different techniques including dynamic light scattering (DLS), NMR spectroscopy and scanning electron microscopy (SEM). These nanogels exhibit hydrodynamic diameter of 452 ± 8 nm with a zeta potential of − 27 mV. The nanogels possess an encapsulation efficiency of 65 ± 3%. Potential of the nanogels for controlled release of curcumin is illustrated by in vitro drug release studies. Hemocompatibility and cytocompatibility of the drug loaded nanogels are evaluated. In vitro cytotoxicity of the bare and curcumin loaded nanogels are analyzed by MTT assay towards MCF-7 cells. The results manifest that curcumin loaded nanogels induce toxicity in MCF-7 cells. Confocal laser scanning microscopy (CLSM) studies indicate in vitro cellular uptake of the nanogels in MCF-7 cells. All these results prove the suitability of the curcumin loaded GA Ald-Gel nanogels for cancer therapy. - Highlights: • Curcumin loaded gum arabic aldehyde-gelatin nanogels were prepared. • Nanogels maintained negative zeta potential after curcumin loading. • Curcumin release is higher at acidic pH compared to neutral pH. • Curcumin loaded GA Ald-Gel nanogels shows toxicity towards MCF-7 cells. • Green fluorescence in MCF-7 cells confirmed the intracellular uptake.

  19. Chirped Pulse-Fourier Transform Microwave Spectroscopy of Ethyl 3-METHYL-3-PHENYLGLYCIDATE (strawberry Aldehyde)

    Science.gov (United States)

    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. Observations of total peroxy nitrates and aldehydes: measurement interpretation and inference of OH radical concentrations

    Directory of Open Access Journals (Sweden)

    P. A. Cleary

    2007-01-01

    Full Text Available We describe measurements of total peroxy nitrates (ΣPNs, NO2, O3 and several aldehydes at Granite Bay, California, during the Chemistry and Transport of the Sacramento Urban Plume-2001 (CATSUP 2001 campaign, from 19 July–16 September 2001. We observed a strong photochemically driven variation of ΣPNs during the day with the median of 1.2 ppb at noon. Acetaldehyde, pentanal, hexanal and methacrolein had median abundances in the daytime of 1.2 ppb, 0.093 ppb, 0.14 ppb, and 0.27 ppb, respectively. We compare steady state and time dependent calculations of the dependence of ΣPNs on aldehydes, OH, NO and NO2 showing that the steady state calculations are accurate to ±30% between 10:00 and 18:00 h. We use the steady state calculation to investigate the composition of ΣPNs and the concentration of OH at Granite Bay. We find that PN molecules that have never been observed before make up an unreasonably large fraction of the ΣPNs unless we assume that there exists a PAN source that is much larger than the acetaldehyde source. We calculate that OH at the site varied between 2 and 7×106 molecule cm−3 at noon during the 8 weeks of the experiment.

  1. Secondary organic aerosol formation during evaporation of droplets containing atmospheric aldehydes, amines, and ammonium sulfate.

    Science.gov (United States)

    Galloway, Melissa M; Powelson, Michelle H; Sedehi, Nahzaneen; Wood, Stephanie E; Millage, Katherine D; Kononenko, Julia A; Rynaski, Alec D; De Haan, David O

    2014-12-16

    Reactions of carbonyl compounds in cloudwater produce organic aerosol mass through in-cloud oxidation and during postcloud evaporation. In this work, postcloud evaporation was simulated in laboratory experiments on evaporating droplets that contain mixtures of common atmospheric aldehydes with ammonium sulfate (AS), methylamine, or glycine. Aerosol diameters were measured during monodisperse droplet drying experiments and during polydisperse droplet equilibration experiments at 75% relative humidity, and condensed-phase mass was measured in bulk thermogravimetric experiments. The evaporation of water from a droplet was found to trigger aldehyde reactions that increased residual particle volumes by a similar extent in room-temperature experiments, regardless of whether AS, methylamine, or glycine was present. The production of organic aerosol volume was highest from droplets containing glyoxal, followed by similar production from methylglyoxal or hydroxyacetone. Significant organic aerosol production was observed for glycolaldehyde, acetaldehyde, and formaldehyde only at elevated temperatures in thermogravimetric experiments. In many experiments, the amount of aerosol produced was greater than the sum of all solutes plus nonvolatile solvent impurities, indicating the additional presence of trapped water, likely caused by increasing aerosol-phase viscosity due to oligomer formation.

  2. Defensome against toxic diatom aldehydes in the sea urchin Paracentrotus lividus.

    Directory of Open Access Journals (Sweden)

    Vincenzo Marrone

    Full Text Available Many diatom species produce polyunsaturated aldehydes, such as decadienal, which compromise embryonic and larval development in benthic organisms. Here newly fertilized Paracentrotus lividus sea urchins were exposed to low concentration of decadienal and the expression levels of sixteen genes, implicated in a broad range of functional responses, were followed by Real Time qPCR in order to identify potential decadienal targets. We show that at low decadienal concentrations the sea urchin Paracentrotus lividus places in motion different classes of genes to defend itself against this toxic aldehyde, activating hsp60 and two proteases, hat and BP10, at the blastula stage and hsp56 and several other genes (14-3-3ε, p38 MAPK, MTase, and GS at the prism stage. At this latter stage all genes involved in skeletogenesis (Nec, uni, SM50 and SM30 were also down-expressed, following developmental abnormalities that mainly affected skeleton morphogenesis. Moreover, sea urchin embryos treated with increasing concentrations of decadienal revealed a dose-dependent response of activated target genes. Finally, we suggest that this orchestrated defense system against decadienal represents part of the chemical defensome of P. lividus affording protection from environmental toxicants.

  3. Sensitive Determination of Volatile Organic Compounds and Aldehydes in Tattoo Inks.

    Science.gov (United States)

    Lim, Hyun-Hee; Shin, Ho-Sang

    2017-02-01

    As the popularity of body art including tattoo ink has increased, the safety associated with it has become an important interest. In this study, twenty volatile organic compounds (VOCs) and two aldehydes in tattoo inks were identified and quantified. Headspace and gas chromatography-mass spectrometry (HS GC-MS) for the VOCs and HS GC-MS based on derivatization with 2,2,2-trifluoroethylhydrazine (TFEH) for aldehydes was developed. Benzene, chloroform, toluene, ethylbenzene, m-xylene, p-xylene, o-xylene, propylbenzene, chlorobenzene, tert-butylbenzene, 1,3,5-trimethylbenzene, styrene, 1,2,4-trimethylbenzene, 2-chlorotoluene, 4-chlorotoluene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene and isopropyl alcohol were detected with the concentration range of 0.02-207,000 mg/kg in 16 different tattoo inks. Formaldehyde and acetaldehyde were detected with the concentration range of 0.4-308 mg/kg in the same samples. Our analytical results represent solvents used intentionally or non-intentionally in tattoo inks, and thus they may provide important information for national regulation. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Antisickling activity evaluation of 4 aromatic aldehydes using proton magnetic relaxation

    International Nuclear Information System (INIS)

    Falcon Dieguez, J.E.; Grisel del Toro Garcia; Yamirka Alonso Geli; Lores Guevara, M.A.

    2006-12-01

    The formation of a Shiff base aduct hemoglobin-aromatic aldehyde, has been reported as inhibitor of the hemoglobin S polymerization. Using the Proton Magnetic Resonance methodology, the polymerization kinetics can be studied and the delay time can be determined. Our studies in vitro show the inhibitor effect of the isovanillin, o-vanillin, m-hydroxybenzaldehyde and the p-hydroxybenzaldehyde, using molar ratio (hemoglobin S/compound) 1:1, 1:4 and 1:8. The td increment (expressed in percents) obtained for each one of the molar ratio was the following: isovanillin: 34±6% (1:1), 68±16% (1:4), ovanillin: 26±10% (1:1), 63±20% (1:4), m-hydroxybelzaldehyde: 16±4% (1:1), 44±12% (1:4) and the phydroxybenzaldehyde: 10±3% (1:1), 32±8% (1:4). In the case of 1:8, the characteristic kinetics curve was not obtained. At the used concentrations, hemolytic activity was not found on the red blood cell. These results confirm the antisickling activity of these aromatic aldehydes, for a technique different to that reported in literature that also allows the quantification of concentration effect. The same ones will facilitate the study of the therapeutic usefulness of these compounds in the sickle cell anemia treatment. (author)

  5. Self-Standing Nanocellulose Janus-Type Films with Aldehyde and Carboxyl Functionalities.

    Science.gov (United States)

    Nypelö, Tiina; Amer, Hassan; Konnerth, Johannes; Potthast, Antje; Rosenau, Thomas

    2018-03-12

    Nanocellulose-based self-standing films are becoming a substrate for flexible electronics, diagnostics, and sensors. Strength and surface chemistry are vital variables for these film-based endeavors, the former is one of the assets of nanocellulose. To contribute to the latter, nanocellulose films are tuned with a side-specific functionalization, having an aldehyde and a carboxyl side. The functionalities were obtained combining premodification of the film components by periodate oxidation with ozone post-treatment. Periodate oxidation of cellulose nanocrystals results in film components that interact through intra- and intermolecular hemiacetals and lead to films with an elastic modulus of 11 GPa. The ozone treatment of one film side induces conversion of the aldehyde into carboxyl functionalities. The ozone treatment on individual crystals was largely destructive. Remarkably, such degradation is not observed for the self-standing film, and the film strength at break is preserved. Preserving a physically intact film despite ozone treatment is a credit to using the dry film structure held together by interparticle covalent linkages. Additionally, gas-phase post-treatment avoids disintegration that could result from immersion into solvents. The crystalline cellulose "Janus" film is suggested as an interfacial component in biomaterial engineering, separation technology, or in layered composite materials for tunable affinity between the layers.

  6. Catalytic wet-air oxidation of lignin in a three-phase reactor with aromatic aldehyde production

    Directory of Open Access Journals (Sweden)

    Sales F.G.

    2004-01-01

    Full Text Available In the present work a process of catalytic wet air oxidation of lignin obtained from sugar-cane bagasse is developed with the objective of producing vanillin, syringaldehyde and p-hydroxybenzaldehyde in a continuous regime. Palladium supported on g-alumina was used as the catalyst. The reactions in the lignin degradation and aldehyde production were described by a kinetic model as a system of complex parallel and series reactions, in which pseudo-first-order steps are found. For the purpose of producing aromatic aldehydes in continuous regime, a three-phase fluidized reactor was built, and it was operated using atmospheric air as the oxidizer. The best yield in aromatic aldehydes was of 12%. The experimental results were compatible with those values obtained by the pseudo-heterogeneous axial dispersion model (PHADM applied to the liquid phase.

  7. Ionic liquids as recyclable and separable reaction media in Rh-catalyzed decarbonylation of aromatic and aliphatic aldehydes

    DEFF Research Database (Denmark)

    Malcho, Phillip; Garcia-Suarez, Eduardo J.; Riisager, Anders

    2014-01-01

    Ionic liquids (ILs) have been applied as recyclable reaction media in the decarbonylation of aldehydes in the presence of a rhodium-phosphine complex catalyst. The performance of several new catalytic systems based on imidazolium-based ILs and [Rh(dppp)2]Cl (dppp: 1,3-diphenylphosphinopropane) were...... excellent in the decarbonylation of both aromatic and aliphatic aldehydes providing >99 yield of benzenes and alkanes, respectively. The catalytic performance depended, however, strongly on the employed IL and its thermal stability. In addition, the ILs afforded good catalyst immobilization as well...

  8. Catabolism of coniferyl aldehyde, ferulic acid and p-coumaric acid by Saccharomyces cerevisiae yields less toxic products.

    Science.gov (United States)

    Adeboye, Peter Temitope; Bettiga, Maurizio; Aldaeus, Fredrik; Larsson, Per Tomas; Olsson, Lisbeth

    2015-09-21

    Lignocellulosic substrates and pulping process streams are of increasing relevance to biorefineries for second generation biofuels and biochemical production. They are known to be rich in sugars and inhibitors such as phenolic compounds, organic acids and furaldehydes. Phenolic compounds are a group of aromatic compounds known to be inhibitory to fermentative organisms. It is known that inhibition of Sacchromyces cerevisiae varies among phenolic compounds and the yeast is capable of in situ catabolic conversion and metabolism of some phenolic compounds. In an approach to engineer a S. cerevisiae strain with higher tolerance to phenolic inhibitors, we selectively investigated the metabolic conversion and physiological effects of coniferyl aldehyde, ferulic acid, and p-coumaric acid in Saccharomyces cerevisiae. Aerobic batch cultivations were separately performed with each of the three phenolic compounds. Conversion of each of the phenolic compounds was observed on time-based qualitative analysis of the culture broth to monitor various intermediate and final metabolites. Coniferyl aldehyde was rapidly converted within the first 24 h, while ferulic acid and p-coumaric acid were more slowly converted over a period of 72 h. The conversion of the three phenolic compounds was observed to involved several transient intermediates that were concurrently formed and converted to other phenolic products. Although there were several conversion products formed from coniferyl aldehyde, ferulic acid and p-coumaric acid, the conversion products profile from the three compounds were similar. On the physiology of Saccharomyces cerevisiae, the maximum specific growth rates of the yeast was not affected in the presence of coniferyl aldehyde or ferulic acid, but it was significantly reduced in the presence of p-coumaric acid. The biomass yields on glucose were reduced to 73 and 54 % of the control in the presence of coniferyl aldehyde and ferulic acid, respectively, biomass yield

  9. Dual Enantioselective Control using D-phenylglycine-L-proline-derived Catalysts for the Enantioselective Addition of Diethylzinc to Aldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seock Yong; Park, Yong Sun [Konkuk University, Seoul (Korea, Republic of)

    2016-01-15

    Dipeptide-derived catalysts are of great interest in various asymmetric transformations because of their short and simple preparation and easy modification of their modular structure by using different α-amino acids. We recently reported the first example of dipeptide-catalyzed enantioselective addition of dialkylzinc to aldehydes. We have developed a novel D-Phg-L-Pro dipeptide-derived catalyst for the addition of diethylzinc to aromatic aldehydes. We also disclosed an effective chiral switching by simply modifying nonchiral part of D-Phg-L-Pro dipeptide.

  10. Threshold photoelectron spectroscopy and photoionization total ion yield spectroscopy of simple organic acids, aldehydes, ketones and amines

    International Nuclear Information System (INIS)

    Yencha, Andrew J; Malins, Andrew E R; Siggel-King, Michele R F; Eypper, Marie; King, George C

    2009-01-01

    We have initiated a research program to investigate the ionization behavior of some simple organic molecules containing the carboxyl group (R 2 C=O), where R could be H, OH, NH 2 , or CH 3 or other aliphatic or aromatic carbon groups, using threshold photoelectron spectroscopy and photoionization total ion yield spectroscopy. We report here on the simplest organic acid, formic acid, and two simple aldehydes: acetaldehyde and the simplest unsaturated aldehyde, 2-propenal (acrolein). The objective of this study was to characterize the valence cationic states of these molecules with vibrational structural resolution.

  11. Chemoselective Preparation of 1,1-Diacetates from Aldehydes, Mediated by a Keggin Heteropolyacid Under Solvent Free Conditions at Room Temperature

    Directory of Open Access Journals (Sweden)

    G. Romanelli

    2007-01-01

    Full Text Available A simple, general and efficient method has been developed for the conversion of aldehydes to 1,1-diacetates using acetic anhydride, a catalytic amount of non commercial Keggin heteropolyacid (H6 PalMo11O40 (1% mol in solvent free conditions at room temperature. Aromatic and aliphatic, simple and conjugated aldehydes were protected with excellent yields.

  12. Development of a microfluidic paper-based analytical device for the determination of salivary aldehydes.

    Science.gov (United States)

    Ramdzan, Adlin N; Almeida, M Inês G S; McCullough, Michael J; Kolev, Spas D

    2016-05-05

    A low cost, disposable and easy to use microfluidic paper-based analytical device (μPAD) was developed for simple and non-invasive determination of total aldehydes in saliva with a potential to be used in epidemiological studies to assess oral cancer risk. The μPAD is based on the colour reaction between aldehydes (e.g. acetaldehyde, formaldehyde), 3-methyl-2-benzothiazolinone hydrazone (MBTH) and iron(III) to form an intense blue coloured formazan dye. The newly developed μPAD has a 3D design with two overlapping paper layers. The first layer comprises 15 circular detection zones (8 mm in diameter), each impregnated with 8 μL of MBTH, while the second layer contains 15 reagent zones (4 mm in diameter). Two μL of iron(III) chloride are added to each one of the second layer zones after the addition of sample to the detection zones in the first layer. All hydrophilic zones of the μPAD are defined by wax printing using a commercial wax printer. Due to the 2-step nature of the analytical reaction, the two paper layers are separated by a cellulose acetate interleaving sheet to allow for the reaction between the aldehydes in the saliva sample with MBTH to proceed first with the formation of an azine, followed by a blue coloured reaction between the azine and the oxidized by iron(III) form of MBTH, produced after the removal of the interleaving sheet. After obtaining a high resolution image of the detection side zone of the device using a flatbed scanner, the intensity of the blue colour within each detection zone is measured with Image J software. Under optimal conditions, the μPAD is characterised by a working range of 20.4-114.0 μM, limit of detection of 6.1 μM, and repeatability, expressed as RSD, of less than 12.7% (n = 5). There is no statistically significant difference at the 95% confidence level between the results obtained by the μPAD and the reference method (Student's t-test: 0.090 < 0.38). The optimized μPAD is stable for more than 41 days

  13. Zinc and glutamate dehydrogenase in putative glutamatergic brain structures.

    Science.gov (United States)

    Wolf, G; Schmidt, W

    1983-01-01

    A certain topographic parallelism between the distribution of histochemically (TIMM staining) identified zinc and putative glutamatergic structures in the rat brain was demonstrated. Glutamate dehydrogenase as a zinc containing protein is in consideration to be an enzyme synthesizing transmitter glutamate. In a low concentration range externally added zinc ions (10(-9) to 10(-7) M) induced an increase in the activity of glutamate dehydrogenase (GDH) originating from rat hippocampal formation, neocortex, and cerebellum up to 142.4%. With rising molarity of Zn(II) in the incubation medium, the enzyme of hippocampal formation and cerebellum showed a biphasic course of activation. Zinc ions of a concentration higher than 10(-6) M caused a strong inhibition of GDH. The effect of Zn(II) on GDH originating from spinal ganglia and liver led only to a decrease of enzyme activity. These results are discussed in connection with a functional correlation between zinc and putatively glutamatergic system.

  14. Lanthanide(III) ion - luminescent and catalytically active center of aniline condensation with butyric aldehyde

    International Nuclear Information System (INIS)

    Bulgakov, R.G.; Kuleshov, S.P.; Makhmutov, A.R.

    2007-01-01

    New type of chemiluminescent-catalytic transformation, where lanthanide(III) ion performs as luminescent and high effective catalytic active center, is observed. The chemiluminescent (CL) is generated in the reaction of aniline condensation with butyric aldehyde in DMFA with the formation of 2-propyl-3-ethyl quinoline that is catalyzed by LnCl 3 ·6H 2 O (Ln=Eu, Tb and Ho). Excited ions Eu* 3+ and Tb* 3+ are served as emitters of CL when using salts EuCl 3 ·6H 2 O and TbCl 3 ·6H 2 O by way of catalysts, and in the case of HoCl 3 ·6H 2 O triplet-excited state of 2-propyl-3-ethyl quinoline ( 3 C 14 H 17 N*) is an emitter of CL [ru

  15. Production of Primary Amines by Reductive Amination of Biomass-Derived Aldehydes/Ketones.

    Science.gov (United States)

    Liang, Guanfeng; Wang, Aiqin; Li, Lin; Xu, Gang; Yan, Ning; Zhang, Tao

    2017-03-06

    Transformation of biomass into valuable nitrogen-containing compounds is highly desired, yet limited success has been achieved. Here we report an efficient catalyst system, partially reduced Ru/ZrO 2 , which could catalyze the reductive amination of a variety of biomass-derived aldehydes/ketones in aqueous ammonia. With this approach, a spectrum of renewable primary amines was produced in good to excellent yields. Moreover, we have demonstrated a two-step approach for production of ethanolamine, a large-market nitrogen-containing chemical, from lignocellulose in an overall yield of 10 %. Extensive characterizations showed that Ru/ZrO 2 -containing multivalence Ru association species worked as a bifunctional catalyst, with RuO 2 as acidic promoter to facilitate the activation of carbonyl groups and Ru as active sites for the subsequent imine hydrogenation. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. New Tailor-Made Alkyl-Aldehyde Bifunctional Supports for Lipase Immobilization

    Directory of Open Access Journals (Sweden)

    Robson Carlos Alnoch

    2016-11-01

    Full Text Available Immobilized and stabilized lipases are important biocatalytic tools. In this paper, different tailor-made bifunctional supports were prepared for the immobilization of a new metagenomic lipase (LipC12. The new supports contained hydrophobic groups (different alkyl groups to promote interfacial adsorption of the lipase and aldehyde groups to react covalently with the amino groups of side chains of the adsorbed lipase. The best catalyst was 3.5-fold more active and 5000-fold more stable than the soluble enzyme. It was successfully used in the regioselective deacetylation of peracetylated d-glucal. The PEGylated immobilized lipase showed high regioselectivity, producing high yields of the C-3 monodeacetylated product at pH 5.0 and 4 °C.

  17. Nature of Intermediates in Organo-SOMO Catalysis of α-Arylation of Aldehydes

    Science.gov (United States)

    Um, Joann M.; Gutierrez, Osvaldo; Schoenebeck, Franziska

    2010-01-01

    The intramolecular α-arylation of aldehydes via organo-SOMO catalysis was investigated using density functional theory (B3LYP and M06-2X functionals). The geometries, spin densities, Mulliken charges, and molecular orbitals of the reacting enamine radical cations were analyzed, and the nature of the resulting cyclized radical cation intermediates were characterized. In agreement with experimental observations, the calculated 1,3-disubstituted aromatic system shows ortho selectivity, while the 1,3,4-trisubstituted systems show para, meta (instead of ortho, meta) selectivity. The selectivity change for the trisubstituted rings is attributed to a distortion of the ortho substituents in the ortho, meta cyclization transition structures, causing a destabilization of these isomers and therefore selectivity for the para, meta product. PMID:20387888

  18. The Barbier-Grignard-type arylation of aldehydes using unactivated aryl iodides in water.

    Science.gov (United States)

    Zhou, Feng; Li, Chao-Jun

    2014-06-26

    Carbon-carbon bond formation is the essence of organic synthesis. One of the most important methods for forming carbon-carbon bonds is the Barbier-Grignard-type reaction, which was discovered over a century ago. However, it is still highly desirable to further improve this process. In this article, we describe a Barbier-Grignard-type direct arylation of aldehydes by using unactivated iodides mediated by zinc and catalysed by rhodium in water. This method bypasses a number of challenges encountered by the conventional Barbier-Grignard reaction, such as strict exclusion of moisture and air, protection-deprotection of various acidic hydrogens in the substrates, and so forth. It thereby creates a safer, more convenient and more environmentally benign strategy to access the diarylmethanols and aryl alkyl alcohols, ubiquitous skeletons found in fine chemicals, biologically active molecules and pharmaceuticals. Importantly, the same reaction performed in an organic solvent proceeded sluggishly to give much inferior yields.

  19. Zinc-mediated α-regioselective Barbier-type cinnamylation reactions of aldehydes, ketones and esters.

    Science.gov (United States)

    Zhao, Li-Ming; Gao, Hua-Shuai; Li, De-Feng; Dong, Jing; Sang, Lan-Lin; Ji, Jie

    2017-05-23

    We report a simple, efficient, and general method for the zinc-mediated regioselective cinnamylation of aldehydes and ketones under Barbier-type conditions in a one-pot synthesis affording the corresponding α-cinnamylated alcohols in moderate to excellent yields. Compared to the literature procedures, this approach is operationally simple, uses simple reactants, and provides direct access to linear α-cinnamylated alcohols with excellent regioselectivity. Experimental results suggest that the reactions proceed through the radical pathway. In addition, the reaction was found to be scalable to the gram-scale and the one-pot protocol is also applicable to less reactive esters leading to bishomoallylic alcohols which were valuable intermediates for desymmetrizing intramolecular Heck cyclization, allowing for the elaboration to functionalized building blocks.

  20. [Experimental research on alcohols, aldehydes, aromatic hydrocarbons and olefins emissions from alcohols fuelled vehicles].

    Science.gov (United States)

    Zhang, Fan; Wang, Jian-Hai; Wang, Xiao-Cheng; Wang, Jian-Xin

    2013-07-01

    Using two vehicles fuelled with pure gasoline, M15, M30 and pure gasoline, E10, E20 separately, 25 degrees C normal temperature type I emission test, -7 degrees C low temperature type VI emission test and type IV evaporation emission test were carried out. FTIR, HPLC and GC-MS methods were utilized to measure alcohols, aldehydes, aromatic hydrocarbons and olefins emissions. The test results indicate that at the low as well as normal ambient temperature, as the alcohols proportion increasing in the fuel, unburned methanol, formaldehyde, acetaldehyde increase proportionally, benzene, toluene, ethylene, propylene, 1,3-butadiene and isobutene decrease slightly. The unregulated emissions at the low ambient temperature are significantly higher than those at the normal ambient temperature. The difference of HC emissions in the entire process of evaporative emission tests of E10, gasoline and M15 fuels is slight. There is a small difference of unregulated emissions in the diurnal test of three fuels.