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Sample records for aldehyde dehydrogenase isozymes

  1. Betaine aldehyde dehydrogenase isozymes of spinach

    SciTech Connect

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

    1986-04-01

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

  2. Betaine aldehyde dehydrogenase in sorghum.

    PubMed Central

    Wood, A J; Saneoka, H; Rhodes, D; Joly, R J; Goldsbrough, P B

    1996-01-01

    The ability to synthesize and accumulate glycine betaine is wide-spread among angiosperms and is thought to contribute to salt and drought tolerance. In plants glycine betaine is synthesized by the two-step oxidation of choline via the intermediate betaine aldehyde, catalyzed by choline monooxygenase and betaine aldehyde dehydrogenase (BADH). Two sorghum (Sorghum bicolor) cDNA clones, BADH1 and BADH15, putatively encoding betaine aldehyde dehydrogenase were isolated and characterized. BADH1 is a truncated cDNA of 1391 bp. BADH15 is a full-length cDNA clone, 1812 bp in length, predicted to encode a protein of 53.6 kD. The predicted amino acid sequences of BADH1 and BADH15 share significant homology with other plant BADHs. The effects of water deficit on BADH mRNA expression, leaf water relations, and glycine betaine accumulation were investigated in leaves of preflowering sorghum plants. BADH1 and BADH15 mRNA were both induced by water deficit and their expression coincided with the observed glycine betaine accumulation. During the course of 17 d, the leaf water potential in stressed sorghum plants reached -2.3 MPa. In response to water deficit, glycine betaine levels increased 26-fold and proline levels increased 108-fold. In severely stressed plants, proline accounted for > 60% of the total free amino acid pool. Accumulation of these compatible solutes significantly contributed to osmotic potential and allowed a maximal osmotic adjustment of 0.405 MPa. PMID:8934627

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

    EPA Science Inventory

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

  4. Aldehyde dehydrogenase protein superfamily in maize.

    PubMed

    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. PMID:22983498

  5. Aldehyde dehydrogenase 1A1 in stem cells and cancer

    PubMed Central

    Tomita, Hiroyuki; Tanaka, Kaori; Tanaka, Takuji; Hara, Akira

    2016-01-01

    The human genome contains 19 putatively functional aldehyde dehydrogenase (ALDH) genes, which encode enzymes critical for detoxification of endogenous and exogenous aldehyde substrates through NAD(P)+-dependent oxidation. ALDH1 has three main isotypes, ALDH1A1, ALDH1A2, and ALDH1A3, and is a marker of normal tissue stem cells (SC) and cancer stem cells (CSC), where it is involved in self-renewal, differentiation and self-protection. Experiments with murine and human cells indicate that ALDH1 activity, predominantly attributed to isotype ALDH1A1, is tissue- and cancer-specific. High ALDH1 activity and ALDH1A1 overexpression are associated with poor cancer prognosis, though high ALDH1 and ALDH1A1 levels do not always correlate with highly malignant phenotypes and poor clinical outcome. In cancer therapy, ALDH1A1 provides a useful therapeutic CSC target in tissue types that normally do not express high levels of ALDH1A1, including breast, lung, esophagus, colon and stomach. Here we review the functions and mechanisms of ALDH1A1, the key ALDH isozyme linked to SC populations and an important contributor to CSC function in cancers, and we outline its potential in future anticancer strategies. PMID:26783961

  6. Molecular mechanism of null expression of aldehyde dehydrogenase-1 in rat liver

    SciTech Connect

    Chen, J.; Yoshida, Akira; Yanagawa, Yuchio

    1996-04-01

    In isozyme systems in general, the pattern of tissue-dependent expression of a given type of isozyme is uniform in various mammalian species. In contrast, a major cytosolic aldehyde dehydrogenase isozyme, termed ALDH1, which is strongly expressed in the livers of humans and other mammals, is hardly detectable in rat liver. Thirteen nucleotides existing in the 5{prime}-promoter region of human, marmoset, and mouse ALDH1 genes are absent in the four rat strains examined. When the 13 nucleotides were deleted from a chloramphenicol acetyltransferase expression construct, which contained the 5{prime} promoter region of the human ALDH1 gene and a low-background promoterless chloramphenicol acetyltransferase expression vector, the expression activity was severely diminished in human hepatic cells. Thus, deletion of the 13 nucleotides in the promoter region of the gene can account for the lack of ALDH1 expression in rat liver. 16 refs., 3 figs.

  7. SAXS fingerprints of aldehyde dehydrogenase oligomers.

    PubMed

    Tanner, John J

    2015-12-01

    Enzymes of the aldehyde dehydrogenase (ALDH) superfamily catalyze the nicotinamide adenine dinucleotide-dependent oxidation of aldehydes to carboxylic acids. ALDHs are important in detoxification of aldehydes, amino acid metabolism, embryogenesis and development, neurotransmission, oxidative stress, and cancer. Mutations in genes encoding ALDHs cause metabolic disorders, including alcohol flush reaction (ALDH2), Sjögren-Larsson syndrome (ALDH3A2), hyperprolinemia type II (ALDH4A1), γ-hydroxybutyric aciduria (ALDH5A1), methylmalonic aciduria (ALDH6A1), pyridoxine dependent epilepsy (ALDH7A1), and hyperammonemia (ALDH18A1). We previously reported crystal structures and small-angle X-ray scattering (SAXS) analyses of ALDHs exhibiting dimeric, tetrameric, and hexameric oligomeric states (Luo et al., Biochemistry 54 (2015) 5513-5522; Luo et al., J. Mol. Biol. 425 (2013) 3106-3120). Herein I provide the SAXS curves, radii of gyration, and distance distribution functions for the three types of ALDH oligomer. The SAXS curves and associated analysis provide diagnostic fingerprints that allow rapid identification of the type of ALDH oligomer that is present in solution. The data sets provided here serve as a benchmark for characterizing oligomerization of ALDHs. PMID:26693506

  8. Targeting Aldehyde Dehydrogenase 2: New Therapeutic Opportunities

    PubMed Central

    Chen, Che-Hong; Ferreira, Julio Cesar Batista; Gross, Eric R.; Mochly-Rosen, Daria

    2014-01-01

    A family of detoxifying enzymes called aldehyde dehydrogenases (ALDHs) has been a subject of recent interest, as its role in detoxifying aldehydes that accumulate through metabolism and to which we are exposed from the environment has been elucidated. Although the human genome has 19 ALDH genes, one ALDH emerges as a particularly important enzyme in a variety of human pathologies. This ALDH, ALDH2, is located in the mitochondrial matrix with much known about its role in ethanol metabolism. Less known is a new body of research to be discussed in this review, suggesting that ALDH2 dysfunction may contribute to a variety of human diseases including cardiovascular diseases, diabetes, neurodegenerative diseases, stroke, and cancer. Recent studies suggest that ALDH2 dysfunction is also associated with Fanconi anemia, pain, osteoporosis, and the process of aging. Furthermore, an ALDH2 inactivating mutation (termed ALDH2*2) is the most common single point mutation in humans, and epidemiological studies suggest a correlation between this inactivating mutation and increased propensity for common human pathologies. These data together with studies in animal models and the use of new pharmacological tools that activate ALDH2 depict a new picture related to ALDH2 as a critical health-promoting enzyme. PMID:24382882

  9. ISOZYME PROFILES OF LACTIC DEHYDROGENASE AND CREATINE PHOSPHOKINASE IN NEONATAL MOUSE HEARTS

    EPA Science Inventory

    Isozyme profiles of lactic dehydrogenase (LDH) and creatine phosphokinase (CPK) were determined in cardiac tissue of mice during postnatal development. LDH isozymes 1 and 5 showed a definite developmental change, achieving the adult values by 20 days of age, while the other three...

  10. Aldehyde Dehydrogenase Inhibitors: a Comprehensive Review of the Pharmacology, Mechanism of Action, Substrate Specificity, and Clinical Application

    PubMed Central

    Koppaka, Vindhya; Thompson, David C.; Chen, Ying; Ellermann, Manuel; Nicolaou, Kyriacos C.; Juvonen, Risto O.; Petersen, Dennis; Deitrich, Richard A.; Hurley, Thomas D.

    2012-01-01

    Aldehyde dehydrogenases (ALDHs) belong to a superfamily of enzymes that play a key role in the metabolism of aldehydes of both endogenous and exogenous derivation. The human ALDH superfamily comprises 19 isozymes that possess important physiological and toxicological functions. The ALDH1A subfamily plays a pivotal role in embryogenesis and development by mediating retinoic acid signaling. ALDH2, as a key enzyme that oxidizes acetaldehyde, is crucial for alcohol metabolism. ALDH1A1 and ALDH3A1 are lens and corneal crystallins, which are essential elements of the cellular defense mechanism against ultraviolet radiation-induced damage in ocular tissues. Many ALDH isozymes are important in oxidizing reactive aldehydes derived from lipid peroxidation and thereby help maintain cellular homeostasis. Increased expression and activity of ALDH isozymes have been reported in various human cancers and are associated with cancer relapse. As a direct consequence of their significant physiological and toxicological roles, inhibitors of the ALDH enzymes have been developed to treat human diseases. This review summarizes known ALDH inhibitors, their mechanisms of action, isozyme selectivity, potency, and clinical uses. The purpose of this review is to 1) establish the current status of pharmacological inhibition of the ALDHs, 2) provide a rationale for the continued development of ALDH isozyme-selective inhibitors, and 3) identify the challenges and potential therapeutic rewards associated with the creation of such agents. PMID:22544865

  11. Aldehyde dehydrogenase inhibitors from the mushroom Clitocybe clavipes.

    PubMed

    Kawagishi, Hirokazu; Miyazawa, Toshiyuki; Kume, Hiroko; Arimoto, Yasushi; Inakuma, Takahiro

    2002-11-01

    Five fatty acid derivatives including three novel compounds were isolated from the mushroom Clitocybe clavipe. Their structures were elucidated by spectral analyses. These compounds inhibited aldehyde dehydrogenase in vitro. PMID:12444711

  12. Human liver aldehyde dehydrogenase: coenzyme binding

    SciTech Connect

    Kosley, L.L.; Pietruszko, R.

    1987-05-01

    The binding of (U-/sup 14/C) NAD to mitochondrial (E2) and cytoplasmin(E1) aldehyde dehydrogenase was measured by gel filtration and sedimentation techniques. The binding data for NAD and (E1) yielded linear Scatchard plots giving a dissociation constant of 25 (+/- 8) uM and the stoichiometry of 2 mol of NAD bound per mol of E1. The binding data for NAD and (E2) gave nonlinear Scatchard plots. The binding of NADH to E2 was measured via fluorescence enhancement; this could not be done with E1 because there was no signal. The dissociation constant for E2 by this technique was 0.7 (+/- 0.4) uM and stoichiometry of 1.0 was obtained. The binding of (U-/sup 14/C) NADH to (E1) and (E2) was also measured by the sedimentation technique. The binding data for (E1) and NADH gave linear Scatchard plots giving a dissociation constant of 13 (+/- 6) uM and the stoichiometry of 2.0. The binding data for NADH to (E2) gave nonlinear Scatchard plots. With (E1), the dissociation constants for both NAD and NADH are similar to those determined kinetically, but the stoichiometry is only half of that found by stopped flow technique. With (E2) the dissociation constant by fluorometric procedure was 2 orders of magnitude less than that from catalytic reaction.

  13. Molecular abnormality of an inactive aldehyde dehydrogenase variant commonly found in Orientals.

    PubMed Central

    Yoshida, A; Huang, I Y; Ikawa, M

    1984-01-01

    Usual human livers contain two major aldehyde dehydrogenase [(ALDH) aldehyde:NAD+ oxidoreductase] isozymes--i.e., a cytosolic ALDH1 component and a mitochondrial ALDH2 component--whereas approximately equal to 50% of Orientals are "atypical" and have only the ALDH1 isozyme and are missing the ALDH2 isozyme. We previously demonstrated that atypical livers contain an enzymatically inactive but immunologically crossreactive material (CRM) corresponding to the ALDH2 component. The enzymatically active ALDH2 obtained from a usual liver and the CRM obtained from an atypical liver were reduced, S-carboxymethylated, and digested by trypsin. Separation of their digests by high-performance reverse-phase chromatography and by two-dimensional paper chromatography and electrophoresis revealed that ALDH2 contained a peptide sequence of -Glu-Leu-Gly-Glu-Ala-Gly-Leu-Gln-Ala-Asn-Val-Gln-Val-Lys- and that the glutamine adjacent to lysine was substituted by lysine in CRM. All other tryptic peptides, including eight peptides containing S-carboxymethylcysteine, were common in ALDH2 and CRM. It is concluded that a point mutation in the human ALDH2 locus produced the glutamine leads to lysine substitution and enzyme inactivation. Images PMID:6582480

  14. Maize cytokinin dehydrogenase isozymes are localized predominantly to the vacuoles.

    PubMed

    Zalabák, David; Johnová, Patricie; Plíhal, Ondřej; Šenková, Karolina; Šamajová, Olga; Jiskrová, Eva; Novák, Ondřej; Jackson, David; Mohanty, Amitabh; Galuszka, Petr

    2016-07-01

    The maize genome encompasses 13 genes encoding for cytokinin dehydrogenase isozymes (CKXs). These enzymes are responsible for irreversible degradation of cytokinin plant hormones and thus, contribute regulating their levels. Here, we focus on the unique aspect of CKXs: their diverse subcellular distribution, important in regulating cytokinin homeostasis. Maize CKXs were tagged with green fluorescent protein (GFP) and transiently expressed in maize protoplasts. Most of the isoforms, namely ZmCKX1, ZmCKX2, ZmCKX4a, ZmCKX5, ZmCKX6, ZmCKX8, ZmCKX9, and ZmCKX12, were associated with endoplasmic reticulum (ER) several hours after transformation. GFP-fused CKXs were observed to accumulate in putative prevacuolar compartments. To gain more information about the spatiotemporal localization of the above isoforms, we prepared stable expression lines of all ZmCKX-GFP fusions in Arabidopsis thaliana Ler suspension culture. All the ER-associated isoforms except ZmCKX1 and ZmCKX9 were found to be targeted primarily to vacuoles, suggesting that ER-localization is a transition point in the intracellular secretory pathway and vacuoles serve as these isoforms' final destination. ZmCKX9 showed an ER-like localization pattern similar to those observed in the transient maize assay. Apoplastic localization of ZmCKX1 was further confirmed and ZmCKX10 showed cytosolic/nuclear localization due to the absence of the signal peptide sequence as previously reported. Additionally, we prepared GFP-fused N-terminal signal deletion mutants of ZmCKX2 and ZmCKX9 and clearly demonstrated that the localization pattern of these mutant forms was cytosolic/nuclear. This study provides the first complex model for spatiotemporal localization of the key enzymes of the cytokinin degradation/catabolism in monocotyledonous plants. PMID:27031423

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

    EPA Science Inventory

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

  16. Aldehyde dehydrogenase (ALDH) in Alzheimer's and Parkinson's disease.

    PubMed

    Grünblatt, Edna; Riederer, Peter

    2016-02-01

    Evidence suggests that aldehyde dehydrogenase (ALDH; E.C. 1.2.1.3) gene, protein expression and activity are substantially decreased in the substantia nigra of patients with Parkinson's disease (PD). This holds especially true for cytosolic ALDH1A1, while mitochondrial ALDH2 is increased in the putamen of PD. Similarly, in Alzheimer's disease (AD) several studies in genetic, transcriptomic, protein and animal models suggest ALDH involvement in the neurodegeneration processes. Such data are in line with findings of increased toxic aldehydes, like for example malondialdehyde, nonenal, 3,4-dihydroxyphenylacetaldehyde and others. Genetic, transcriptomic and protein alterations may contribute to such data. Also in vitro and in vivo experimental work points to an important role of ALDH in the pathology of neurodegenerative disorders. Aims at investigating dysfunctions of aldehyde detoxification are suitable to define genetic/molecular targets for new therapeutic strategies balancing amine metabolism in devastating disorders like PD and probably also AD. PMID:25298080

  17. Drosophila melanogaster alcohol dehydrogenase: mechanism of aldehyde oxidation and dismutation.

    PubMed

    Winberg, J O; McKinley-McKee, J S

    1998-02-01

    Drosophila alcohol dehydrogenase (Adh) catalyses the oxidation of both alcohols and aldehydes. In the latter case, the oxidation is followed by a reduction of the aldehyde, i.e. a dismutation reaction. At high pH, dismutation is accompanied by a small release of NADH, which is not observed at neutral pH. Previously it has been emphasized that kinetic coefficients obtained by measuring the increase in A340, i.e. the release of NADH at high pH is not a direct measure of the aldehyde oxidation reaction and these values cannot be compared with those for alcohol dehydrogenation. In this article we demonstrate that this is not entirely true, and that the coefficients phiB and phiAB, where B is the aldehyde and A is NAD+, are the same for a dismutation reaction and a simple aldehyde dehydrogenase reaction. Thus the substrate specificity of the aldehyde oxidation reaction can be determined by simply measuring the NADH release. The coefficients for oxidation and dehydrogenation reactions (phi0d and phiAd respectively) are complex and involve the constants for the dismutation reaction. However, dead-end inhibitors can be used to determine the quantitative contribution of the kinetic constants for the aldehyde oxidation and reduction pathways to the phi0d and phiAd coefficients. The combination of dead-end and product inhibitors can be used to determine the reaction mechanism for the aldehyde oxidation pathway. Previously, we showed that with Drosophila Adh, the interconversion between alcohols and aldehydes followed a strictly compulsory ordered pathway, although aldehydes and ketones formed binary complexes with the enzyme. This raised the question regarding the reaction mechanism for the oxidation of aldehydes, i.e. whether a random ordered pathway was followed. In the present work, the mechanism for the oxidation of different aldehydes and the accompanying dismutation reaction with the slow alleloenzyme (AdhS) from Drosophila melanogaster has been studied. To obtain

  18. Drosophila melanogaster alcohol dehydrogenase: mechanism of aldehyde oxidation and dismutation.

    PubMed Central

    Winberg, J O; McKinley-McKee, J S

    1998-01-01

    Drosophila alcohol dehydrogenase (Adh) catalyses the oxidation of both alcohols and aldehydes. In the latter case, the oxidation is followed by a reduction of the aldehyde, i.e. a dismutation reaction. At high pH, dismutation is accompanied by a small release of NADH, which is not observed at neutral pH. Previously it has been emphasized that kinetic coefficients obtained by measuring the increase in A340, i.e. the release of NADH at high pH is not a direct measure of the aldehyde oxidation reaction and these values cannot be compared with those for alcohol dehydrogenation. In this article we demonstrate that this is not entirely true, and that the coefficients phiB and phiAB, where B is the aldehyde and A is NAD+, are the same for a dismutation reaction and a simple aldehyde dehydrogenase reaction. Thus the substrate specificity of the aldehyde oxidation reaction can be determined by simply measuring the NADH release. The coefficients for oxidation and dehydrogenation reactions (phi0d and phiAd respectively) are complex and involve the constants for the dismutation reaction. However, dead-end inhibitors can be used to determine the quantitative contribution of the kinetic constants for the aldehyde oxidation and reduction pathways to the phi0d and phiAd coefficients. The combination of dead-end and product inhibitors can be used to determine the reaction mechanism for the aldehyde oxidation pathway. Previously, we showed that with Drosophila Adh, the interconversion between alcohols and aldehydes followed a strictly compulsory ordered pathway, although aldehydes and ketones formed binary complexes with the enzyme. This raised the question regarding the reaction mechanism for the oxidation of aldehydes, i.e. whether a random ordered pathway was followed. In the present work, the mechanism for the oxidation of different aldehydes and the accompanying dismutation reaction with the slow alleloenzyme (AdhS) from Drosophila melanogaster has been studied. To obtain

  19. Human liver mitochondrial aldehyde dehydrogenase: three-dimensional structure and the restoration of solubility and activity of chimeric forms.

    PubMed Central

    Ni, L.; Zhou, J.; Hurley, T. D.; Weiner, H.

    1999-01-01

    Human liver cytosolic and mitochondrial isozymes of aldehyde dehydrogenase share 70% sequence identity. However, the first 21 residues are not conserved between the human isozymes (15% identity). The three-dimensional structures of the beef mitochondrial and sheep cytosolic forms have virtually identical three-dimensional structures. Here, we solved the structure of the human mitochondrial enzyme and found it to be identical to the beef enzyme. The first 21 residues are found on the surface of the enzyme and make no contact with other subunits in the tetramer. A pair of chimeric enzymes between the human isozymes was made. Each chimera had the first 21 residues from one isozyme and the remaining 479 from the other. When the first 21 residues were from the mitochondrial isozyme, an enzyme with cytosolic-like properties was produced. The other was expressed but was insoluble. It was possible to restore solubility and activity to the chimera that had the first 21 cytosolic residues fused to the mitochondrial ones by making point mutations to residues at the N-terminal end. When residue 19 was changed from tyrosine to a cysteine, the residue found in the mitochondrial form, an active enzyme could be made though the Km for NAD+ was 35 times higher than the native mitochondrial isozyme and the specific activity was reduced by 75%. This residue interacts with residue 203, a nonconserved, nonactive site residue. A mutation of residue 18, which also interacts with 203, restored solubility, but not activity. Mutation to residue 15, which interacts with 104, also restored solubility but not activity. It appears that to have a soluble or active enzyme a favorable interaction must occur between a residue in a surface loop and a residue elsewhere in the molecule even though neither make contact with the active site region of the enzyme. PMID:10631996

  20. Baboon alcohol dehydrogenase isozymes: phenotypic changes in liver following chronic consumption of alcohol.

    PubMed

    Holmes, R S; VandeBerg, J L

    1987-01-01

    According to the nomenclature of Vallee and Bazzone [1983] for mammalian alcohol dehydrogenase (ADH) isozymes, baboon ADHs comprise three major classes of activity, which were distinguished according to the following properties: Class I ADHs. These isozymes exhibited low-Km characteristics with ethanol as substrate, high isoelectric points (8.5-9.3), and sensitivity to 5 mM 4-methyl pyrazole inhibition, and were the major liver (ADH-2) and kidney (ADH-1) isozymes in the baboon. Class II ADHs. These isozymes showed high-Km values for ethanol, neutral isoelectric points (7.7 for the liver ADH-4 [pi-ADH] and 7.2 for the major stomach ADH [ADH-3], respectively), and were insensitive to inhibition with 5 mM 4-methyl pyrazole. Class III ADH. This enzyme was characterized by its inactivity with ethanol as substrate (up to 0.5 M), insensitivity to 4-methyl pyrazole inhibition, preference for medium-chain-length alcohols as substrate (trans-2-hexen-1-ol was routinely used in this study), and an isoelectric point (6.5) similar to that of the human liver chi-ADH (pI 6.4). Major activity variation of the liver pi-ADH (ADH-4) isozyme was observed among the 114 liver samples examined, with 34 percent exhibiting a null (or low-activity) phenotype. An electrophoretic variant phenotype for the major class II stomach isozyme (ADH-3) was also found in the population studied. The baboon was used as a model for studying alcohol-induced changes in liver ADH phenotype following chronic alcohol consumption. Prepuberal male baboons were pair-fed nutritionally adequate liquid diets containing ethanol (50 percent of calories) or isocaloric carbohydrates, and liver ADH isozyme patterns from biopsy samples were monitored for 20 weeks. Dramatic decreases in class II liver ADH activity (ADH-4, or pi-ADH) were observed within 4 weeks after the start of alcohol feeding, and a shift in liver class I isozymes was found during the later stages of alcohol consumption. These changes during chronic

  1. Some properties of aldehyde dehydrogenase from sheep liver mitochondria.

    PubMed Central

    Hart, G J; Dickinson, F M

    1977-01-01

    Aldehyde dehydrogenase from sheep liver mitochondria was purified to homogeneity as judged by electrophoresis on polyacrylamide gels, and by sedimentation-equilibrium experiments in the analytical ultracentrifuge. The enzyme has a molecular weight of 198000 and a subunit size of 48000, indicating that the molecule is a tetramer. Fluorescence and spectrophotometric titrations indicate that each subunit can bind 1 molecule of NADH. Enzymic activity is completely blocked by reaction of 4mol of 5,5'-dithiobis-(2-nitrobenzoate)/mol of enzyme. Excess of disulfiram or iodoacetamide decreases activity to only 50% of the control value, and only two thiol groups per molecule are apparently modified by these reagents. PMID:194582

  2. A coniferyl aldehyde dehydrogenase gene from Pseudomonas sp. strain HR199 enhances the conversion of coniferyl aldehyde by Saccharomyces cerevisiae.

    PubMed

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

    2016-07-01

    The conversion of coniferyl aldehyde to cinnamic acids by Saccharomyces cerevisiae under aerobic growth conditions was previously observed. Bacteria such as Pseudomonas have been shown to harbor specialized enzymes for converting coniferyl aldehyde but no comparable enzymes have been identified in S. cerevisiae. CALDH from Pseudomonas was expressed in S. cerevisiae. An acetaldehyde dehydrogenase (Ald5) was also hypothesized to be actively involved in the conversion of coniferyl aldehyde under aerobic growth conditions in S. cerevisiae. In a second S. cerevisiae strain, the acetaldehyde dehydrogenase (ALD5) was deleted. A prototrophic control strain was also engineered. The engineered S. cerevisiae strains were cultivated in the presence of 1.1mM coniferyl aldehyde under aerobic condition in bioreactors. The results confirmed that expression of CALDH increased endogenous conversion of coniferyl aldehyde in S. cerevisiae and ALD5 is actively involved with the conversion of coniferyl aldehyde in S. cerevisiae. PMID:27070284

  3. Non-P450 aldehyde oxidizing enzymes: the aldehyde dehydrogenase superfamily

    PubMed Central

    Marchitti, Satori A; Brocker, Chad; Stagos, Dimitrios; Vasiliou, Vasilis

    2009-01-01

    Background Aldehydes are highly reactive molecules. While several non-P450 enzyme systems participate in their metabolism, one of the most important is the aldehyde dehydrogenase (ALDH) superfamily, composed of NAD(P)+-dependent enzymes that catalyze aldehyde oxidation. Objective This article presents a review of what is currently known about each member of the human ALDH superfamily including the pathophysiological significance of these enzymes. Methods Relevant literature involving all members of the human ALDH family was extensively reviewed, with the primary focus on recent and novel findings. Conclusion To date, 19 ALDH genes have been identified in the human genome and mutations in these genes and subsequent inborn errors in aldehyde metabolism are the molecular basis of several diseases, including Sjögren-Larsson syndrome, type II hyperprolinemia, γ-hydroxybutyric aciduria and pyridoxine-dependent seizures. ALDH enzymes also play important roles in embryogenesis and development, neurotransmission, oxidative stress and cancer. Finally, ALDH enzymes display multiple catalytic and non-catalytic functions including ester hydrolysis, antioxidant properties, xenobiotic bioactivation and UV light absorption. PMID:18611112

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

    PubMed

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

    2016-04-01

    In plants, the last step in the biosynthesis of the osmoprotectant glycine betaine (GB) is the NAD(+)-dependent oxidation of betaine aldehyde (BAL) catalysed by some aldehyde dehydrogenase (ALDH) 10 enzymes that exhibit betaine aldehyde dehydrogenase (BADH) activity. Given the irreversibility of the reaction, the short-term regulation of these enzymes is of great physiological relevance to avoid adverse decreases in the NAD(+):NADH ratio. In the present study, we report that the Spinacia oleracea BADH (SoBADH) is reversibly and partially inactivated by BAL in the absence of NAD(+)in a time- and concentration-dependent mode. Crystallographic evidence indicates that the non-essential Cys(450)(SoBADH numbering) forms a thiohemiacetal with BAL, totally blocking the productive binding of the aldehyde. It is of interest that, in contrast to Cys(450), the catalytic cysteine (Cys(291)) did not react with BAL in the absence of NAD(+) The trimethylammonium group of BAL binds in the same position in the inactivating or productive modes. Accordingly, BAL does not inactivate the C(450)SSoBADH mutant and the degree of inactivation of the A(441)I and A(441)C mutants corresponds to their very different abilities to bind the trimethylammonium group. Cys(450)and the neighbouring residues that participate in stabilizing the thiohemiacetal are strictly conserved in plant ALDH10 enzymes with proven or predicted BADH activity, suggesting that inactivation by BAL is their common feature. Under osmotic stress conditions, this novel partial and reversible covalent regulatory mechanism may contribute to preventing NAD(+)exhaustion, while still permitting the synthesis of high amounts of GB and avoiding the accumulation of the toxic BAL. PMID:26792760

  5. Aldehyde dehydrogenases in cellular responses to oxidative/electrophilic stress.

    PubMed

    Singh, Surendra; Brocker, Chad; Koppaka, Vindhya; Chen, Ying; Jackson, Brian C; Matsumoto, Akiko; Thompson, David C; Vasiliou, Vasilis

    2013-03-01

    Reactive oxygen species (ROS) are continuously generated within living systems and the inability to manage ROS load leads to elevated oxidative stress and cell damage. Oxidative stress is coupled to the oxidative degradation of lipid membranes, also known as lipid peroxidation. This process generates over 200 types of aldehydes, many of which are highly reactive and toxic. Aldehyde dehydrogenases (ALDHs) metabolize endogenous and exogenous aldehydes and thereby mitigate oxidative/electrophilic stress in prokaryotic and eukaryotic organisms. ALDHs are found throughout the evolutionary gamut, from single-celled organisms to complex multicellular species. Not surprisingly, many ALDHs in evolutionarily distant, and seemingly unrelated, species perform similar functions, including protection against a variety of environmental stressors such as dehydration and ultraviolet radiation. The ability to act as an "aldehyde scavenger" during lipid peroxidation is another ostensibly universal ALDH function found across species. Upregulation of ALDHs is a stress response in bacteria (environmental and chemical stress), plants (dehydration, salinity, and oxidative stress), yeast (ethanol exposure and oxidative stress), Caenorhabditis elegans (lipid peroxidation), and mammals (oxidative stress and lipid peroxidation). Recent studies have also identified ALDH activity as an important feature of cancer stem cells. In these cells, ALDH expression helps abrogate oxidative stress and imparts resistance against chemotherapeutic agents such as oxazaphosphorine, taxane, and platinum drugs. The ALDH superfamily represents a fundamentally important class of enzymes that contributes significantly to the management of electrophilic/oxidative stress within living systems. Mutations in various ALDHs are associated with a variety of pathological conditions in humans, highlighting the fundamental importance of these enzymes in physiological and pathological processes. PMID:23195683

  6. Activity and electrophoretic profiles of liver aldehyde dehydrogenases from mice of inbred strains with different alcohol preference.

    PubMed

    Yamazaki, H; Nishiguchi, K; Miyamoto, R; Ogita, Z I; Nakanishi, S

    1983-01-01

    1. The activity of low Km-aldehyde dehydrogenase (ALDH) in the liver mitochondrial fraction (MT-fraction) from male C57BL/6J strain mice (alcohol preferring) was significantly higher than that from DBA/2 mice (alcohol avoiding). The F1 hybrids (C57BL/6J X DBA/2) did not exhibit the intermediate activity to these two strains. 2. Strain differences in liver mitochondrial ALDH isozymes were observed by isoelectric focusing. C57BL/6J strain had two isozymes at pH 7.1 while DBA/2 had no band at this pH. F1 hybrid mice had similar two bands with lower density to those of C57BL/6J at pH 7.1. There was no difference in zymograms of the soluble fraction between C57BL/6J and DBA/2 strains. 3. The present results suggest that the difference in alcohol preference of mice may depend on some restricted ALDH isozymes with different pl or electric mobility rather than the enzymatic activity in the liver MT-fraction. PMID:6822317

  7. [Characterization of aldehyde dehydrogenase gene fragment from mung bean Vigna radiata using the polymerase chain reaction].

    PubMed

    Ponomarev, A G; Bubiakina, V V; Tatarinova, T D; Zelenin, S M

    1998-01-01

    Two degenerate oligonucleotide sequence primers and polymerase chain reactions on total DNA have been utilized to clone on 651--bp gene fragment coding the central part of amino acid sequence of an earlier unknown aldehyde dehydrogenase (ALDH) from mung bean. The deduced partial amino acid sequence for this aldehyde dehydrogenase shows about 65% sequence identity to ALDHs of Vibrio cholerae Rhodococcus sp., Alcaligenes eutrophus and about 45% sequence identity to mammalian ALDHs 1 and 2, ALDHs of Aspergillus niger and A, nidulans, the betain aldehyde dehydrogenase from spinach. Alignment of the mung bean aldehyde dehydrogenase partial amino acid sequence with the sequence of 16 NAD(P)(+)-dependent aldehyde dehydrogenases has demonstrated that all strictly conserved amino acid residues and all three conservative regions are identical. PMID:9778740

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

    PubMed

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

    2010-01-01

    The association between two functional polymorphisms in alcohol dehydrogenase (ADH2/ADH1B) and aldehyde dehydrogenase (ALDH2) genes and alcohol dependence was examined in 182 Chinese and Indian patients undergoing treatment for alcohol dependence and 184 screened control subjects from Singapore. All subjects were screened by the Alcohol Use Disorders Identification Test (AUDIT). Patients were also administered the Severity of Alcohol Dependence Questionnaire (SADQ). Polymorphisms were genotyped by allele-specific polymerase chain reaction and selected genotypes confirmed by DNA sequencing or restriction fragment length polymorphism. Our results showed that frequencies of ADH1B*2 and ALDH2*2 were higher in controls compared to alcohol-dependent subjects for both Chinese and Indians. Frequencies of these two alleles were also higher in the 104 Chinese controls compared to the 80 Indian controls. None of the eight Chinese who were homozygous for both protective alleles was alcohol dependent. The higher frequencies of the protective alleles could explain the lower rate of alcohol dependence in Chinese. PMID:20025435

  9. Discovery of NCT-501, a Potent and Selective Theophylline-Based Inhibitor of Aldehyde Dehydrogenase 1A1 (ALDH1A1).

    PubMed

    Yang, Shyh-Ming; Yasgar, Adam; Miller, Bettina; Lal-Nag, Madhu; Brimacombe, Kyle; Hu, Xin; Sun, Hongmao; Wang, Amy; Xu, Xin; Nguyen, Kimloan; Oppermann, Udo; Ferrer, Marc; Vasiliou, Vasilis; Simeonov, Anton; Jadhav, Ajit; Maloney, David J

    2015-08-13

    Aldehyde dehydrogenases (ALDHs) metabolize reactive aldehydes and possess important physiological and toxicological functions in areas such as CNS, metabolic disorders, and cancers. Increased ALDH (e.g., ALDH1A1) gene expression and catalytic activity are vital biomarkers in a number of malignancies and cancer stem cells, highlighting the need for the identification and development of small molecule ALDH inhibitors. A new series of theophylline-based analogs as potent ALDH1A1 inhibitors is described. The optimization of hits identified from a quantitative high throughput screening (qHTS) campaign led to analogs with improved potency and early ADME properties. This chemotype exhibits highly selective inhibition against ALDH1A1 over ALDH3A1, ALDH1B1, and ALDH2 isozymes as well as other dehydrogenases such as HPGD and HSD17β4. Moreover, the pharmacokinetic evaluation of selected analog 64 (NCT-501) is also highlighted. PMID:26207746

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

    PubMed Central

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

    2009-01-01

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

  11. Aldehyde dehydrogenase activity promotes survival of human muscle precursor cells

    PubMed Central

    Jean, Elise; Laoudj-Chenivesse, Dalila; Notarnicola, Cécile; Rouger, Karl; Serratrice, Nicolas; Bonnieu, Anne; Gay, Stéphanie; Bacou, Francis; Duret, Cédric; Carnac, Gilles

    2011-01-01

    Abstract Aldehyde dehydrogenases (ALDH) are a family of enzymes that efficiently detoxify aldehydic products generated by reactive oxygen species and might therefore participate in cell survival. Because ALDH activity has been used to identify normal and malignant cells with stem cell properties, we asked whether human myogenic precursor cells (myoblasts) could be identified and isolated based on their levels of ALDH activity. Human muscle explant-derived cells were incubated with ALDEFLUOR, a fluorescent substrate for ALDH, and we determined by flow cytometry the level of enzyme activity. We found that ALDH activity positively correlated with the myoblast-CD56+ fraction in those cells, but, we also observed heterogeneity of ALDH activity levels within CD56-purified myoblasts. Using lentiviral mediated expression of shRNA we demonstrated that ALDH activity was associated with expression of Aldh1a1 protein. Surprisingly, ALDH activity and Aldh1a1 expression levels were very low in mouse, rat, rabbit and non-human primate myoblasts. Using different approaches, from pharmacological inhibition of ALDH activity by diethylaminobenzaldehyde, an inhibitor of class I ALDH, to cell fractionation by flow cytometry using the ALDEFLUOR assay, we characterized human myoblasts expressing low or high levels of ALDH. We correlated high ALDH activity ex vivo to resistance to hydrogen peroxide (H2O2)-induced cytotoxic effect and in vivo to improved cell viability when human myoblasts were transplanted into host muscle of immune deficient scid mice. Therefore detection of ALDH activity, as a purification strategy, could allow non-toxic and efficient isolation of a fraction of human myoblasts resistant to cytotoxic damage. PMID:19840193

  12. An animal model of human aldehyde dehydrogenase deficiency

    SciTech Connect

    Chang, C.; Mann, J.; Yoshida, A.

    1994-09-01

    The genetic deficiency of ALDH2, a major mitochondrial aldehyde dehydrogenase, is intimately related to alcohol sensitivity and the degree of predisposition to alcoholic diseases in humans. The ultimate biological role of ALDH2 can be exposed by knocking out the ALDH2 gene in an animal model. As the first step for this line of studies, we cloned and characterized the ALDH2 gene from mouse C57/6J strain which is associated with a high alcohol preference. The gene spans 26 kbp and is composed of 13 exons. Embryonic stem cells were transfected with a replacement vector which contains a partially deleted exon3, a positive selection cassette (pPgk Neo), exon 4 with an artificial stop codon, exons 5, 6, 7, and a negative selection cassette (pMCI-Tk). Genomic DNAs prepared from drug resistant clones were analyzed by polymerase chain reaction and by Southern blot analysis to distinguish random integration from homologous recombination. Out of 132 clones examined, 8 had undergone homologous recombination at one of the ALDH2 alleles. The cloned transformed embryonic stem cells with a disrupted ALDH2 allele were injected into blastocysts. Transplantation of the blastocysts into surrogate mother mice yielded chimeric mice. The role of ALDH2 in alcohol preference, alcohol sensitivity and other biological and behavioral characteristics can be elucidated by examining the heterozygous and homozygous mutant strains produced by breeding of chimeric mice.

  13. Intracellular localization of aldehyde dehydrogenase in rat liver

    PubMed Central

    Marjanen, Leo

    1972-01-01

    1. Distribution of aldehyde dehydrogenase activity in rat liver was studied by measuring the rate of disappearance of acetaldehyde in the presence of each of the subcellular fractions. These were obtained by rough separation of particulate fractions from the soluble portion of the cell, by differential centrifugation, and by isopycnic gradient centrifugation. 2. The maximal rate of acetaldehyde oxidation was 3.7 μmol/min per g, with an apparent Km value below 10−5m. The highest rate of activity was observed in phosphate buffers of high Pi concentration (above 60mm). 3. The activity measured was completely dependent on NAD+. 4. The microsomal fraction and the nuclei were inactive in the assay. Of the total activity 80% was found in the mitochondrial fraction and the remaining 20% in the cytoplasm. 5. The distribution pattern is important from the point of view of acetaldehyde oxidation during ethanol metabolism. The apparent discrepancy of the results obtained by different workers and the localization of acetaldehyde oxidation in vivo is discussed. PMID:4346744

  14. Targeting Aldehyde Dehydrogenase Cancer Stem Cells in Ovarian Cancer

    PubMed Central

    Landen, Charles N.; Goodman, Blake; Katre, Ashwini A.; Steg, Adam D.; Nick, Alpa M.; Stone, Rebecca L.; Miller, Lance D.; Mejia, Pablo Vivas; Jennings, Nicolas B.; Gershenson, David M.; Bast, Robert C.; Coleman, Robert L.; Lopez-Berestein, Gabriel; Sood, Anil K.

    2010-01-01

    Aldehyde dehydrogenase-1A1 (ALDH1A1) expression characterizes a subpopulation of cells with tumor initiating or cancer stem cell properties in several malignancies. Our goal was to characterize the phenotype of ALDH1A1-positive ovarian cancer cells and examine the biological effects of ALDH1A1 gene silencing. In our analysis of multiple ovarian cancer cell lines, we found that ALDH1A1 expression and activity was significantly higher in taxane and platinum-resistant cell lines. In patient samples, 72.9% of ovarian cancers had ALDH1A1 expression, in whom the percent of ALDH1A1-positive cells correlated negatively with progression-free survival (6.05 v 13.81 months, p<0.035). Subpopulations of A2780cp20 cells with ALDH1A1 activity were isolated for orthotopic tumor initiating studies, where tumorigenicity was approximately 50-fold higher with ALDH1A1-positive cells. Interestingly, tumors derived from ALDH1A1-positive cells gave rise to both ALDH1A1-positive and ALDH1A1-negative populations, but ALDH1A1-negative cells could not generate ALDH1A1-positive cells. In an in vivo orthotopic mouse model of ovarian cancer, ALDH1A1 silencing using nanoliposomal siRNA sensitized both taxane- and platinum-resistant cell lines to chemotherapy, significantly reducing tumor growth in mice compared to chemotherapy alone (a 74–90% reduction, p<0.015). These data demonstrate that the ALDH1A1 subpopulation is associated with chemoresistance and outcome in ovarian cancer patients, and targeting ALDH1A1 sensitizes resistant cells to chemotherapy. ALDH1A1-positive cells have enhanced, but not absolute, tumorigenicity, but do have differentiation capacity lacking in ALDH1A1-negative cells. This enzyme may be important for identification and targeting of chemoresistant cell populations in ovarian cancer. PMID:20889728

  15. Bioactivation of Nitroglycerin by Purified Mitochondrial and Cytosolic Aldehyde Dehydrogenases*

    PubMed Central

    Beretta, Matteo; Gruber, Karl; Kollau, Alexander; Russwurm, Michael; Koesling, Doris; Goessler, Walter; Keung, Wing Ming; Schmidt, Kurt; Mayer, Bernd

    2008-01-01

    Metabolism of nitroglycerin (GTN) to 1,2-glycerol dinitrate (GDN) and nitrite by mitochondrial aldehyde dehydrogenase (ALDH2) is essentially involved in GTN bioactivation resulting in cyclic GMP-mediated vascular relaxation. The link between nitrite formation and activation of soluble guanylate cyclase (sGC) is still unclear. To test the hypothesis that the ALDH2 reaction is sufficient for GTN bioactivation, we measured GTN-induced formation of cGMP by purified sGC in the presence of purified ALDH2 and used a Clark-type electrode to probe for nitric oxide (NO) formation. In addition, we studied whether GTN bioactivation is a specific feature of ALDH2 or is also catalyzed by the cytosolic isoform (ALDH1). Purified ALDH1 and ALDH2 metabolized GTN to 1,2- and 1,3-GDN with predominant formation of the 1,2-isomer that was inhibited by chloral hydrate (ALDH1 and ALDH2) and daidzin (ALDH2). GTN had no effect on sGC activity in the presence of bovine serum albumin but caused pronounced cGMP accumulation in the presence of ALDH1 or ALDH2. The effects of the ALDH isoforms were dependent on the amount of added protein and, like 1,2-GDN formation, were sensitive to ALDH inhibitors. GTN caused biphasic sGC activation with apparent EC50 values of 42 ± 2.9 and 3.1 ± 0.4 μm in the presence of ALDH1 and ALDH2, respectively. Incubation of ALDH1 or ALDH2 with GTN resulted in sustained, chloral hydrate-sensitive formation of NO. These data may explain the coupling of ALDH2-catalyzed GTN metabolism to sGC activation in vascular smooth muscle. PMID:18450747

  16. Bifunctional aldehyde/alcohol dehydrogenase (ADHE) in chlorophyte algal mitochondria.

    PubMed

    Atteia, Ariane; van Lis, Robert; Mendoza-Hernández, Guillermo; Henze, Katrin; Martin, William; Riveros-Rosas, Hector; González-Halphen, Diego

    2003-09-01

    Protein profiles of mitochondria isolated from the heterotrophic chlorophyte Polytomella sp. grown on ethanol at pH 6.0 and pH 3.7 were analyzed by Blue Native and denaturing polyacrylamide gel electrophoresis. Steady-state levels of oxidative phosphorylation complexes were influenced by external pH. Levels of an abundant, soluble, mitochondrial protein of 85 kDa and its corresponding mRNA increased at pH 6.0 relative to pH 3.7. N-terminal and internal sequencing of the 85 kDa mitochondrial protein together with the corresponding cDNA identified it as a bifunctional aldehyde/alcohol dehydrogenase (ADHE) with strong similarity to homologues from eubacteria and amitochondriate protists. A mitochondrial targeting sequence of 27 amino acids precedes the N-terminus of the mature mitochondrial protein. A gene encoding an ADHE homologue was also identified in the genome of Chlamydomonas reinhardtii, a photosynthetic relative of Polytomella. ADHE reveals a complex picture of sequence similarity among homologues. The lack of ADHE from archaebacteria indicates a eubacterial origin for the eukaryotic enzyme. Among eukaryotes, ADHE has hitherto been characteristic of anaerobes since it is essential to cytosolic energy metabolism of amitochondriate protists such as Giardia intestinalis and Entamoeba histolytica. Its abundance and expression pattern suggest an important role for ADHE in mitochondrial metabolism of Polytomella under the conditions studied. The current data are compatible with the view that Polytomella ADHE could be involved either in ethanol production or assimilation, or both, depending upon environmental conditions. Presence of ADHE in an oxygen-respiring algal mitochondrion and co-expression at ambient oxygen levels with respiratory chain components is unexpected with respect to the view that eukaryotes acquired ADHE genes specifically as an adaptation to an anaerobic lifestyle. PMID:14756315

  17. Vascular Bioactivation of Nitroglycerin by Aldehyde Dehydrogenase-2

    PubMed Central

    Lang, Barbara S.; Gorren, Antonius C. F.; Oberdorfer, Gustav; Wenzl, M. Verena; Furdui, Cristina M.; Poole, Leslie B.; Mayer, Bernd; Gruber, Karl

    2012-01-01

    Aldehyde dehydrogenase-2 (ALDH2) catalyzes the bioactivation of nitroglycerin (glyceryl trinitrate, GTN) in blood vessels, resulting in vasodilation by nitric oxide (NO) or a related species. Because the mechanism of this reaction is still unclear we determined the three-dimensional structures of wild-type (WT) ALDH2 and of a triple mutant of the protein that exhibits low denitration activity (E268Q/C301S/C303S) in complex with GTN. The structure of the triple mutant showed that GTN binds to the active site via polar contacts to the oxyanion hole and to residues 268 and 301 as well as by van der Waals interactions to hydrophobic residues of the catalytic pocket. The structure of the GTN-soaked wild-type protein revealed a thionitrate adduct to Cys-302 as the first reaction intermediate, which was also found by mass spectrometry (MS) experiments. In addition, the MS data identified sulfinic acid as the irreversibly inactivated enzyme species. Assuming that the structures of the triple mutant and wild-type ALDH2 reflect binding of GTN to the catalytic site and the first reaction step, respectively, superposition of the two structures indicates that denitration of GTN is initiated by nucleophilic attack of Cys-302 at one of the terminal nitrate groups, resulting in formation of the observed thionitrate intermediate and release of 1,2-glyceryl dinitrate. Our results shed light on the molecular mechanism of the GTN denitration reaction and provide useful information on the structural requirements for high affinity binding of organic nitrates to the catalytic site of ALDH2. PMID:22988236

  18. Aldehyde dehydrogenases: From eye crystallins to metabolic disease and cancer stem cells

    PubMed Central

    Vasiliou, Vasilis; Thompson, David C.; Smith, Clay; Fujita, Mayumi; Chen, Ying

    2014-01-01

    The aldehyde dehydrogenase (ALDH) superfamily is composed of nicotinamide adenine dinucleotide (phosphate) (NAD(P)+)-dependent enzymes that catalyze the oxidation of aldehydes to their corresponding carboxylic acids. To date, 24 ALDH gene families have been identified in the eukaryotic genome. In addition to aldehyde metabolizing capacity, ALDHs have additional catalytic (e.g. esterase and reductase) and non-catalytic activities. The latter include functioning as structural elements in the eye (crystallins) and as binding molecules to endobiotics and xenobiotics. Mutations in human ALDH genes and subsequent inborn errors in aldehyde metabolism are the molecular basis of several diseases. Most recently ALDH polymorphisms have been associated with gout and osteoporosis. Aldehyde dehydrogenase enzymes also play important roles in embryogenesis and development, neurotransmission, oxidative stress and cancer. This article serves as a comprehensive review of the current state of knowledge regarding the ALDH superfamily and the contribution of ALDHs to various physiological and pathophysiological processes. PMID:23159885

  19. Chemical modification of aldehyde dehydrogenase by a vinyl ketone analogue of an insect pheromone.

    PubMed

    Blatter, E E; Tasayco, M L; Prestwich, G; Pietruszko, R

    1990-12-01

    A major component of the sex pheromone from the tobacco budworm moth Heliothis virescens is a C16 straight-chain aldehyde with a single unsaturation at the eleventh position. The sex pheromones are inactivated when metabolized to their corresponding acids by insect aldehyde dehydrogenase. During this investigation it was demonstrated that the C16 aldehyde is a good substrate for human aldehyde dehydrogenase (EC 1.2.1.3) isoenzymes E1 and E2 with Km and Kcat. values at pH 7.0 of 2 microM and 0.4 mumol of NADH/min per mg and of 0.6 microM and 0.24 mumol of NADH/min per mg respectively. A vinyl ketone analogue of the pheromone inhibited insect pheromone metabolism; it also inactivated human aldehyde dehydrogenase. Total inactivation of both isoenzymes was achieved at stoichiometric (equal or less than the subunit number) concentrations of vinyl ketone, incorporating 2.1-2.6 molecules/molecule of enzyme. Substrate protection was observed in the presence of the parent aldehyde and 5'-AMP. Peptide maps of tryptic digests of the E2 isoenzyme modified with 3H-labelled vinyl ketone showed that incorporation occurred into a single peptide peak. The labelled peptide of E2 isoenzyme was further purified on h.p.l.c. and sequenced. The label was incorporated into cysteine-302 in the primary structure of E2 isoenzyme, thus indicating that cysteine-302 is located in the aldehyde substrate area of the active site of aldehyde dehydrogenase. Affinity labelling of aldehyde dehydrogenase with vinyl ketones may prove to be of general utility in biochemical studies of these enzymes. PMID:2268265

  20. Separate physiological roles for two isozymes of pyridine nucleotide-linked glycerol-3-phosphate dehydrogenase in chicken.

    NASA Technical Reports Server (NTRS)

    White, H. B., III; Kaplan, N. O.

    1972-01-01

    The isozymes considered are designated 'liver type' and 'muscle type' based on the tissue of highest concentration. Electrophoretic analysis shows that the liver type is found in small amounts or is undetectable in all tissues studied except liver. The muscle type is found in skeletal muscles and kidney. Presumptive hybrid enzymes occur at low levels in chicken liver and kidney. The tissue distribution of glyceron-3-P dehydrogenase in several birds capable of sustained flight is different than in chicken.

  1. A human alcohol dehydrogenase gene (ADH6) encoding an additional class of isozyme.

    PubMed Central

    Yasunami, M; Chen, C S; Yoshida, A

    1991-01-01

    The human alcohol dehydrogenase (ADH; alcohol:NAD+ oxidoreductase, EC 1.1.1.1) gene family consists of five known loci (ADH1-ADH5), which have been mapped close together on chromosome 4 (4q21-25). ADH isozymes encoded by these genes are grouped in three distinct classes in terms of their enzymological properties. A moderate structural similarity is observed between the members of different classes. We isolated an additional member of the ADH gene family by means of cross-hybridization with the ADH2 (class I) cDNA probe. cDNA clones corresponding to this gene were derived from PCR-amplified libraries as well. The coding sequence of a 368-amino-acid-long open reading frame was interrupted by introns into eight exons and spanned approximately 17 kilobases on the genome. The gene contains a glucocorticoid response element at the 5' region. The transcript was detected in the stomach and liver. The deduced amino acid sequence of the open reading frame showed about 60% positional identity with known human ADHs. This extent of homology is comparable to interclass similarity in the human ADH family. Thus, the newly identified gene, which is designated ADH6, governs the synthesis of an enzyme that belongs to another class of ADHs presumably with a distinct physiological role. Images PMID:1881901

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

    PubMed Central

    Ma, Yu-mei; Zhao, Shan

    2016-01-01

    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 addition, the prognostic value of an individual ALDH1 isoenzyme in ovarian cancer is not clear. Thus, we accessed the prognostic value of ALDH1 isoenzymes in ovarian cancer patients through the “Kaplan–Meier plotter” online database, which can be used to determine the effect of the genes on ovarian cancer prognosis. We found that high mRNA expression of five ALDH1 isoenzymes, such as ALDH1A1, ALDH1A2, ALDH1A3, ALDH1B1, and ALDH1L1, was not correlated with overall survival (OS) for all 1,306 ovarian cancer patients. In addition, all five of the ALDH1 isoenzymes’ high mRNA expression was found to be uncorrelated with OS in serous cancer or endometrioid cancer patients. However, ALDH1A3’s high mRNA expression is associated with worse OS in grade II ovarian cancer patients, hazard ratio (HR) 1.53 (1.14–2.07), P=0.005. ALDH1A2’s high mRNA expression is significantly associated with worse OS in TP53 wild-type ovarian cancer patients, HR 2.86 (1.56–5.08), P=0.00036. In addition, ALDH1A3’s high mRNA expression is significantly associated with better OS in TP53 wild-type ovarian cancer patients, HR 0.56 (0.32–1.00), P=0.04. Our results indicate that although ALDH1 isoenzyme mRNA might not be a prognostic marker for overall ovarian cancer patients, some isoenzymes, such as ALDH1A2 and ALDH1A3, might be a good prognostic marker for some types of ovarian cancer patients. PMID:27110126

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

    PubMed Central

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

    2015-01-01

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

  4. Low Km aldehyde dehydrogenase (ALDH2) polymorphism, alcohol-drinking behavior, and chromosome alterations in peripheral lymphocytes.

    PubMed Central

    Morimoto, K; Takeshita, T

    1996-01-01

    Excessive drinking of alcohol is now widely known to be one of the major lifestyle choices that ca effect health. Among the various effects of alcohol drinking, cytogenetic and other genotoxic effects are of major concern from the viewpoint of prevention of alcohol-related diseases. Alcohol is first metabolized to acetaldehyde, which directly causes various types of chromosomal DNA lesions and alcohol-related diseases, and is then further detoxified to the much less toxic metabolite acetate. About 50% of Oriental people are deficient in the aldehyde-dehydrogenase 2 isozyme (ALDH2) that can most efficiently detoxify acetaldehyde. We have performed a series of experiments to investigate how the genetic deficiency in ALDH2 affects the behavioral pattern for alcohol drinking and the sensitivity of peripheral lymphocytes to the induction of chromosome alterations by exposure to alcohol and alcohol-related chemicals. We found great effects of the ALDH2 genotypes on alcohol sensitivity and alcohol-drinking behavior. We also show that lymphocytes from habitual drinkers with the deficient ALDH2 enzyme had significantly higher frequencies of sister chromatid exchanges than those from ALDH2-proficient individuals. PMID:8781384

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

    PubMed

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

    2016-09-25

    Plant NAD(+)-dependent aminoaldehyde dehydrogenases (AMADHs, EC 1.2.1.19) belong to the family 10 of aldehyde dehydrogenases. They participate in the metabolism of polyamines or osmoprotectants. The enzymes are characterized by their broad substrate specificity covering ω-aminoaldehydes, aliphatic and aromatic aldehydes as well as nitrogen-containing heterocyclic aldehydes. The isoenzyme 1 from tomato (Solanum lycopersicum; SlAMADH1) oxidizes aliphatic aldehydes very efficiently and converts also furfural, its derivatives or benzaldehyde, which are present at low concentrations in alcoholic distillates such as fruit brandy. In this work, SlAMADH1 was examined as a bioanalytical tool for their detection. These aldehydes arise from fermentation processes or thermal degradation of sugars and their presence is related to health complications after consumption including nausea, emesis, sweating, decrease in blood pressure, hangover headache, among others. Sixteen samples of slivovitz (plum brandy) from local producers in Moravia, Czech Republic, were analyzed for their aldehyde content using a spectrophotometric activity assay with SlAMADH1. In all cases, there were oxidative responses observed when monitoring NADH production in the enzymatic reaction. Aldehydes in the distillate samples were also subjected to a standard determination using reversed-phase HPLC with spectrophotometric and tandem mass spectrometric detection after a derivatization with 2,4-dinitrophenylhydrazine. Results obtained by both methods were found to correlate well for a majority of the analyzed samples. The possible applicability of SlAMADH1 for the evaluation of aldehyde content in food and beverages has now been demonstrated. PMID:26703808

  6. Neurodegeneration and motor dysfunction in mice lacking cytosolic and mitochondrial aldehyde dehydrogenases: implications for Parkinson's disease.

    PubMed

    Wey, Margaret Chia-Ying; Fernandez, Elizabeth; Martinez, Paul Anthony; Sullivan, Patricia; Goldstein, David S; Strong, Randy

    2012-01-01

    Previous studies have reported elevated levels of biogenic aldehydes in the brains of patients with Parkinson's disease (PD). In the brain, aldehydes are primarily detoxified by aldehyde dehydrogenases (ALDH). Reduced ALDH1 expression in surviving midbrain dopamine neurons has been reported in brains of patients who died with PD. In addition, impaired complex I activity, which is well documented in PD, reduces the availability of the NAD(+) co-factor required by multiple ALDH isoforms to catalyze the removal of biogenic aldehydes. We hypothesized that chronically decreased function of multiple aldehyde dehydrogenases consequent to exposure to environmental toxins and/or reduced ALDH expression, plays an important role in the pathophysiology of PD. To address this hypothesis, we generated mice null for Aldh1a1 and Aldh2, the two isoforms known to be expressed in substantia nigra dopamine neurons. Aldh1a1(-/-)×Aldh2(-/-) mice exhibited age-dependent deficits in motor performance assessed by gait analysis and by performance on an accelerating rotarod. Intraperitoneal administration of L-DOPA plus benserazide alleviated the deficits in motor performance. We observed a significant loss of neurons immunoreactive for tyrosine hydroxylase (TH) in the substantia nigra and a reduction of dopamine and metabolites in the striatum of Aldh1a1(-/-)×Aldh2(-/-) mice. We also observed significant increases in biogenic aldehydes reported to be neurotoxic, including 4-hydroxynonenal (4-HNE) and the aldehyde intermediate of dopamine metabolism, 3,4-dihydroxyphenylacetaldehyde (DOPAL). These results support the hypothesis that impaired detoxification of biogenic aldehydes may be important in the pathophysiology of PD and suggest that Aldh1a1(-/-)×Aldh2(-/-) mice may be a useful animal model of PD. PMID:22384032

  7. Fatty aldehyde dehydrogenases in Acinetobacter sp. strain HO1-N: role in hexadecane and hexadecanol metabolism

    SciTech Connect

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

    1985-12-01

    The role of fatty aldehyde dehydrogenases (FALDHs) in hexadecane and hexadecanol metabolism was studied in Acinetobacter sp. strain HO1-N. Two distinct FALDHs were demonstrated in Acinetobacter sp. strain HO1-N: (i) a membrane-bound, NADP-dependent FALDH activity induced 5-, 15-, and 9 fold by growth on hexadecanol, dodecyl aldehyde, and hexadecane, respectively, and (ii) a constitutive, NAD-dependent, membrane-localized FALDH. Dodecyl aldehyde-negative mutants were isolated and grouped into two phenotypic classes based on growth: class 1 mutants were hexadecane and hexadecanol negative and class 2 mutants were hexadecane and hexadecanol positive. Specific activity of NADP-dependent FALDH in Ald21 (class 1 mutant) was 85% lower than that of wild-type FALDH, while the specific activity of Ald24 (class 2 mutant) was 55% greater than that of wild-type FALDH. Ald21R, a dodecyl aldehyde-positive revertant able to grow on hexadecane, hexadecanol, and dodecyl aldehyde, exhibited a 100% increase in the specific activity of the NADP-dependent FALDH. This study provides genetic and physiological evidence for the role of fatty aldehyde as an essential metabolic intermediate and NADP-dependent FALDH as a key enzyme in the dissimilation of hexadecane, hexadecanol, and dodecyl aldehyde in Acinetobacter sp. strain HO1-N.

  8. Mesenchymal Stem/Stromal Cells Derived From a Reproductive Tissue Niche Under Oxidative Stress Have High Aldehyde Dehydrogenase Activity.

    PubMed

    Kusuma, Gina D; Abumaree, Mohamed H; Pertile, Mark D; Perkins, Anthony V; Brennecke, Shaun P; Kalionis, Bill

    2016-06-01

    The use of mesenchymal stem/stromal cells (MSC) in regenerative medicine often requires MSC to function in environments of high oxidative stress. Human pregnancy is a condition where the mother's tissues, and in particular her circulatory system, are exposed to increased levels of oxidative stress. MSC in the maternal decidua basalis (DMSC) are in a vascular niche, and thus would be exposed to oxidative stress products in the maternal circulation. Aldehyde dehydrogenases (ALDH) are a large family of enzymes which detoxify aldehydes and thereby protect stem cells against oxidative damage. A subpopulation of MSC express high levels of ALDH (ALDH(br)) and these are more potent in repairing and regenerating tissues. DMSC was compared with chorionic villous MSC (CMSC) derived from the human placenta. CMSC reside in vascular niche and are exposed to the fetal circulation, which is in lower oxidative state. We screened an ALDH isozyme cDNA array and determined that relative to CMSC, DMSC expressed high levels of ALDH1 family members, predominantly ALDH1A1. Immunocytochemistry gave qualitative confirmation at the protein level. Immunofluorescence detected ALDH1 immunoreactivity in the DMSC and CMSC vascular niche. The percentage of ALDH(br) cells was calculated by Aldefluor assay and DMSC showed a significantly higher percentage of ALDH(br) cells than CMSC. Finally, flow sorted ALDH(br) cells were functionally potent in colony forming unit assays. DMSC, which are derived from pregnancy tissues that are naturally exposed to high levels of oxidative stress, may be better candidates for regenerative therapies where MSC must function in high oxidative stress environments. PMID:26880140

  9. Suppressing glioblastoma stem cell function by aldehyde dehydrogenase inhibition with chloramphenicol or disulfiram as a new treatment adjunct: an hypothesis.

    PubMed

    Kast, Richard E; Belda-Iniesta, Cristobal

    2009-12-01

    Strong expression of aldehyde dehydrogenase is a prominent feature of both normal and cancer stem cells, including the stem cell sub-population of glioblastoma. Aldehyde dehydrogenase function is used by cancer stem cells to repopulate a tumor mass after chemotherapy cytoreduction. Cancer stem cells tend to be chemotherapy compared to the non-stem cell majority cell population in several common human cancers. Such has been demonstrated specifically in glioblastoma. In normal hematopoietic stem cells with unimpaired high levels of aldehyde dehydrogenase, stem cells divide rarely and then asymmetrically to a daughter stem cell and a daughter cell on a path of differentiation or symmetrically with both daughter cells on a differentiated path. If a parallel situation obtains in glioblastoma stem cells, the migrating, far flung paucicellular extensions will be stem cell rich and use aldehyde dehydrogenase to generate the characteristic multiple metastases made up of mostly non-stem cells. With inhibition of aldehyde dehydrogenase, stem cell division to non-stem daughter cells tends to become blocked. We have three old yet potent aldehyde dehydrogenase inhibitors on the market- chloral hydrate, chloramphenicol, and disulfiram- they should be investigated as adjuncts in glioblastoma chemotherapy. If GBM stem cell function can be thwarted by potent aldehyde dehydrogenase inhibition, they will be less able to regenerate a stem cell derived tumor mass after primary resection or chemotherapy. PMID:19500061

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

    PubMed Central

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

    2015-01-01

    When exposed to high osmolarity, methicillin-resistant Staphylococcus aureus (MRSA) restores its growth and establishes a new steady state by accumulating the osmoprotectant metabolite betaine. Effective osmoregulation has also been implicated in the acquirement of a profound antibiotic resistance by MRSA. Betaine can be obtained from the bacterial habitat or produced intracellularly from choline via the toxic betaine aldehyde (BA) employing the choline dehydrogenase and betaine aldehyde dehydrogenase (BADH) enzymes. Here, it is shown that the putative betaine aldehyde dehydrogenase SACOL2628 from the early MRSA isolate COL (SaBADH) utilizes betaine aldehyde as the primary substrate and nicotinamide adenine dinucleotide (NAD+) as the cofactor. Surface plasmon resonance experiments revealed that the affinity of NAD+, NADH and BA for SaBADH is affected by temperature, pH and buffer composition. Five crystal structures of the wild type and three structures of the Gly234Ser mutant of SaBADH in the apo and holo forms provide details of the molecular mechanisms of activity and substrate specificity/inhibition of this enzyme. PMID:25945581

  11. Modulation of ethanol stress tolerance by aldehyde dehydrogenase in the mycorrhizal fungus Tricholoma vaccinum.

    PubMed

    Asiimwe, Theodore; Krause, Katrin; Schlunk, Ines; Kothe, Erika

    2012-08-01

    We report the first mycorrhizal fungal aldehyde dehydrogenase gene, ald1, which was isolated from the basidiomycete Tricholoma vaccinum. The gene, encoding a protein Ald1 of 502 amino acids, is up-regulated in ectomycorrhiza. Phylogenetic analyses using 53 specific fungal aldehyde dehydrogenases from all major phyla in the kingdom of fungi including Ald1 and two partial sequences of T. vaccinum were performed to get an insight in the evolution of the aldehyde dehydrogenase family. By using competitive and real-time RT-PCR, ald1 is up-regulated in response to alcohol and aldehyde-related stress. Furthermore, heterologous expression of ald1 in Escherichia coli and subsequent in vitro enzyme activity assay demonstrated the oxidation of propionaldehyde and butyraldehyde with different kinetics using either NAD(+) or NADP(+) as cofactors. In addition, overexpression of ald1 in T. vaccinum after Agrobacterium tumefaciens-mediated transformation increased ethanol stress tolerance. These results demonstrate the ability of Ald1 to circumvent ethanol stress, a critical function in mycorrhizal habitats. PMID:22159964

  12. Acyloin production from aldehydes in the perfused rat heart: the potential role of pyruvate dehydrogenase.

    PubMed Central

    Montgomery, J A; Jetté, M; Huot, S; Des Rosiers, C

    1993-01-01

    Aldehydes represent an important class of cytotoxic products derived from free radical-induced lipid peroxidation which may contribute to reperfusion injury following myocardial infarct. Metabolism of aldehydes in the heart has not been well characterized aside from conjugation of unsaturated aldehydes with glutathione. However, aliphatic aldehydes like hexanal do not form stable glutathione conjugates. We have recently demonstrated in vitro that pig heart pyruvate dehydrogenase catalyses a reaction between pyruvate and saturated aldehydes to produce acyloins (3-hydroxyalkan-2-ones). In the present study, rat hearts were perfused with various aldehydes and pyruvate. Acyloins were generated from saturated aldehydes (butanal, hexanal or nonanal), but not from 2-hexanal (an unsaturated aldehyde) or malondialdehyde. Hearts perfused with 2 mM pyruvate and 10-100 microM hexanal rapidly took up hexanal in a dose-related manner (140-850 nmol/min), and released 3-hydroxyoctan-2-one (0.7-30 nmol/min), 2,3-octanediol (0-12 nmol/min) and hexanol (10-200 nmol/min). Small quantities of hexanoic acid (about 10 nmol/min) were also released. The rate of release of acyloin metabolites rose with increased concentration of hexanal, whereas hexanol release attained a plateau when hexanal infusion concentrations rose above 50 microM. Up to 50% of hexanal uptake could be accounted for by metabolite release. Less than 0.5% of hexanal uptake was found to be bound to acid-precipitable macromolecules. When hearts perfused with 50 microM hexanal and 2 mM pyruvate were subjected to a 15 min ischaemic period, the rates of release of 2,3-octanediol, 3-hydroxyoctan-2-one, hexanol and hexanoate during the reperfusion period were not significantly different from those in the pre-ischaemic period. Our results indicate that saturated aldehydes can be metabolically converted by the heart into stable diffusible compounds. PMID:8379929

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    SciTech Connect

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

    1990-02-25

    Aldehyde dehydrogenase (ALDH) and oxidase (AO) enzymes from the tissue extracts of male and female tobacco budworm moth (Heliothis virescens) were identified after electrophoretic protein separation. AO activity was visualized using formazan- or horseradish peroxidase-mediated staining coupled to the AO-catalyzed oxidation of benzaldehyde. A set of six soluble AO enzymes with isoelectric points from pI 4.6 to 5.3 were detected primarily in the antennal extracts. Partially purified antennal AO enzymes also oxidized both (Z)-9-tetradecenal and (Z)-11-hexadecenal, the two major pheromone components of this moth. ALDH activity was detected using a tritium-labeled affinity reagent based on a known irreversible inhibitor 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.

  15. Oxidation of fatty aldehydes to fatty acids by Escherichia coli cells expressing the Vibrio harveyi fatty aldehyde dehydrogenase (FALDH).

    PubMed

    Buchhaupt, Markus; Guder, Jan; Sporleder, Fenja; Paetzold, Melanie; Schrader, Jens

    2013-03-01

    Fatty acids represent an important renewable feedstock for the chemical industry. To enable biotechnological one carbon truncations of fatty acids, the enzymes α-dioxygenase and fatty aldehyde dehydrogenase (FALDH) have to be combined in a two-step process. We expressed an FALDH from V. harveyi in E. coli and characterized its substrate spectrum with a focus on the number and position of double bonds in the fatty aldehyde molecules. Synthesis of the expected fatty acid products was proven by analysis of whole cell biotransformation products. Coexpression of a H(2)O-forming NADPH oxidase (NOX) from Lactobacillus sanfranciscensis led to the implementation of a cofactor regeneration cycle in in vitro oxidation experiments. The presence of NOX in whole cell biotransformations improved reaction velocity but did not result in higher product yields. We could further demonstrate that at least part of the endogenous NAD(P)(+) regeneration capacity in the resting cells results from the respiratory chain. The whole cell catalyst with the high broad range FALDH activity described here is an important biotechnological module for lipid biotransformation processes, especially the shortening of fatty acids. PMID:23180547

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  17. Crystallization and preliminary X-ray analysis of aldehyde dehydrogenase from Vibrio harveyi.

    PubMed Central

    Croteau, N.; Vedadi, M.; Delarge, M.; Meighen, E.; Abu-Abed, M.; Howell, P. L.; Vrielink, A.

    1996-01-01

    Aldehyde dehydrogenase from Vibrio harveyi catalyzes the oxidation of long-chain aliphatic aldehydes to acids. The enzyme is unique among the family of aldehyde dehydrogenases in that it exhibits much higher specificity for the cofactor NADP+ than for NAD+. The sequence of this form of the enzyme varies significantly from the NAD+ dependent forms, suggesting differences in the three-dimensional structure that may be correlated to cofactor specificity. Crystals of the enzyme have been grown both in the presence and absence of NADP+ using the hanging drop vapor diffusion technique. In order to improve crystal size and quality, iterative seeding techniques were employed. The crystals belong to space group P2(1), with unit cell dimensions a = 79.4 A, b = 131.1 A, c = 92.2 A, and beta = 92.4 degrees. Freezing the crystal to 100 K has enabled a complete set of data to be collected using a rotating anode source (lambda = 1.5418 A). The crystals diffract to a minimum d-spacing of 2.6 A resolution. Based on density calculations, two homodimers of molecular weight 110 kDa are estimated to be present in the asymmetric unit. Self-rotation functions show the presence of 3 noncrystallographic twofold symmetry axes. PMID:8897616

  18. Rice Aldehyde Dehydrogenase7 Is Needed for Seed Maturation and Viability1[W][OA

    PubMed Central

    Shin, Jun-Hye; Kim, Sung-Ryul; An, Gynheung

    2009-01-01

    Aldehyde dehydrogenases (ALDHs) catalyze the irreversible oxidation of a wide range of reactive aldehydes to their corresponding carboxylic acids. Although the proteins have been studied from various organisms and at different growth stages, their roles in seed development have not been well elucidated. We obtained T-DNA insertional mutants in OsALDH7, which is remarkably inducible by oxidative and abiotic stresses. Interestingly, endosperms from the osaldh7 null mutants accumulated brown pigments during desiccation and storage. Extracts from the mutant seeds showed a maximum absorbance peak at 360 nm, the wavelength that melanoidin absorbs. Under UV light, those extracts also exhibited much stronger fluorescence than the wild type, suggesting that the pigments are melanoidin. These pigments started to accumulate in the late seed developmental stage, the time when OsALDH7 expression began to increase significantly. Purified OsALDH7 protein showed enzyme activities to malondialdehyde, acetaldehyde, and glyceraldehyde. These results suggest that OsALDH7 is involved in removing various aldehydes formed by oxidative stress during seed desiccation. The mutant seeds were more sensitive to our accelerated aging treatment and accumulated more malondialdehyde than the wild type. These data imply that OsALDH7 plays an important role in maintaining seed viability by detoxifying the aldehydes generated by lipid peroxidation. PMID:19052152

  19. Aldehyde dehydrogenase-2 regulates nociception in rodent models of acute inflammatory pain

    PubMed Central

    Zambelli, Vanessa O.; Gross, Eric R.; Chen, Che-Hong; Gutierrez, Vanessa P.; Cury, Yara; Mochly-Rosen, Daria

    2014-01-01

    Exogenous aldehydes can cause pain in animal models, suggesting that aldehyde dehydrogenase 2 (ALDH2), which metabolizes many aldehydes, may regulate nociception. To test this hypothesis, we generated a knock-in mouse with an inactivating point mutation in ALDH2 (ALDH2*2), which is also present in human ALDH2 of ~540 million East Asians. The ALDH2*1/*2 heterozygotic mice exhibited a larger response to painful stimuli than their wild-type littermates, and this heightened nociception was inhibited by an ALDH2-selective activator (Alda-1). No effect on inflammation per se was observed. Using a rat model, we then showed that nociception tightly correlated with ALDH activity (R2=0.90) and that reduced nociception was associated with less early growth response protein 1 (EGR1) in the spinal cord and less reactive aldehyde accumulation at the insult site (including acetaldehyde and 4-hydroxynonenal). Further, acetaldehyde and formalin-induced nociceptive behavior was greater in the ALDH2*1/*2 mice than wild-type mice. Finally, Alda-1 treatment was also beneficial when given even after the inflammatory agent was administered. Our data in rodent models suggest that the mitochondrial enzyme ALDH2 regulates nociception and could serve as a molecular target for pain control, with ALDH2 activators, such as Alda-1, as potential non-narcotic cardiac-safe analgesics. Furthermore, our results suggest a possible genetic basis for East Asians’ apparent lower pain tolerance. PMID:25163478

  20. Discovery of a novel class of covalent inhibitor for aldehyde dehydrogenases

    SciTech Connect

    Khanna, Mary; Chen, Che-Hong; Kimble-Hill, Ann; Parajuli, Bibek; Perez-Miller, Samantha; Baskaran, Sulochanadevi; Kim, Jeewon; Dria, Karl; Vasiliou, Vasilis; Mochly-Rosen, Daria; Hurley, Thomas D.

    2012-10-23

    Human aldehyde dehydrogenases (ALDHs) comprise a family of 17 homologous enzymes that metabolize different biogenic and exogenic aldehydes. To date, there are relatively few general ALDH inhibitors that can be used to probe the contribution of this class of enzymes to particular metabolic pathways. Here, we report the discovery of a general class of ALDH inhibitors with a common mechanism of action. The combined data from kinetic studies, mass spectrometric measurements, and crystallographic analyses demonstrate that these inhibitors undergo an enzyme-mediated {beta}-elimination reaction generating a vinyl ketone intermediate that covalently modifies the active site cysteine residue present in these enzymes. The studies described here can provide the basis for rational approach to design ALDH isoenzyme-specific inhibitors as research tools and perhaps as drugs, to address diseases such as cancer where increased ALDH activity is associated with a cellular phenotype.

  1. Characterization of a periplasmic quinoprotein from Sphingomonas wittichii that functions as aldehyde dehydrogenase.

    PubMed

    Zeiser, Jessica; Mühlenbeck, Larissa Helen; Schweiger, Paul; Deppenmeier, Uwe

    2014-03-01

    The α-proteobacterium Sphingomonas wittichii RW1 is known for its ability to degrade dioxins and related toxic substances. Bioinformatic analysis of the genome indicated that this organism may contain the largest number of pyrroloquinoline quinone-dependent dehydrogenases of any bacteria sequenced so far. Sequence analysis also showed that one of these genes (swit_4395) encodes an enzyme that belongs to the class of periplasmic glucose dehydrogenases. This gene was fused to a pelB signal sequence and a strep-tag coding region at the 5' and 3' ends, respectively. The fusion product was cloned into the broad-host range expression vector pBBR1p264-Streplong and the corresponding protein was heterologously produced in Escherichia coli, purified via Strep-Tactin affinity chromatography, and characterized. The protein Swit_4395 had a subunit mass of 39.3 kDa and formed active homooctamers and homododecamers. The enzyme showed the highest activities with short- and medium-chain aldehydes (chain length C1-C6) and ketoaldehydes, such as methylglyoxal and phenylglyoxal. Butyraldehyde was the best substrate, with V max and apparent K M values of 3,970 U/mg protein and 12.3 mM, respectively. Pyrroloquinoline quinone was detected using UV-Vis spectroscopy and was found to be a prosthetic group of the purified enzyme. Therefore, Swit_4395 was identified as a pyrroloquinoline quinone-dependent aldehyde dehydrogenase. The enzyme could be purified from the native host when the expression vector was introduced into S. wittichii RW1, indicating homologous protein production. Overproduction of Swit_4395 in S. wittichii RW1 dramatically increased the tolerance of the bacterium toward butyraldehyde and thus might contribute to the detoxification of toxic aldehydes. PMID:23828599

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

    PubMed

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

    2015-05-15

    Aldehyde dehydrogenases (ALDHs) are responsible for oxidation of biogenic aldehyde intermediates as well as for cell detoxification of aldehydes generated during lipid peroxidation. So far, 13 ALDH families have been described in plants. In the present study, we provide a detailed biochemical characterization of plant ALDH2 and ALDH7 families by analysing maize and pea ALDH7 (ZmALDH7 and PsALDH7) and four maize cytosolic ALDH(cALDH)2 isoforms RF2C, RF2D, RF2E and RF2F [the first maize ALDH2 was discovered as a fertility restorer (RF2A)]. We report the crystal structures of ZmALDH7, RF2C and RF2F at high resolution. The ZmALDH7 structure shows that the three conserved residues Glu(120), Arg(300) and Thr(302) in the ALDH7 family are located in the substrate-binding site and are specific to this family. Our kinetic analysis demonstrates that α-aminoadipic semialdehyde, a lysine catabolism intermediate, is the preferred substrate for plant ALDH7. In contrast, aromatic aldehydes including benzaldehyde, anisaldehyde, cinnamaldehyde, coniferaldehyde and sinapaldehyde are the best substrates for cALDH2. In line with these results, the crystal structures of RF2C and RF2F reveal that their substrate-binding sites are similar and are formed by an aromatic cluster mainly composed of phenylalanine residues and several nonpolar residues. Gene expression studies indicate that the RF2C gene, which is strongly expressed in all organs, appears essential, suggesting that the crucial role of the enzyme would certainly be linked to the cell wall formation using aldehydes from phenylpropanoid pathway as substrates. Finally, plant ALDH7 may significantly contribute to osmoprotection because it oxidizes several aminoaldehydes leading to products known as osmolytes. PMID:25734422

  3. Structural Basis of Substrate Recognition by Aldehyde Dehydrogenase 7A1.

    PubMed

    Luo, Min; Tanner, John J

    2015-09-01

    Aldehyde dehydrogenase 7A1 (ALDH7A1) is part of lysine catabolism and catalyzes the NAD(+)-dependent oxidation of α-aminoadipate semialdehyde to α-aminoadipate. Herein, we describe a structural study of human ALDH7A1 focused on substrate recognition. Five crystal structures and small-angle X-ray scattering data are reported, including the first crystal structure of any ALDH7 family member complexed with α-aminoadipate. The product binds with the ε-carboxylate in the oxyanion hole, the aliphatic chain packed into an aromatic box, and the distal end of the product anchored by electrostatic interactions with five conserved residues. This binding mode resembles that of glutamate bound to the proline catabolic enzyme ALDH4A1. Analysis of ALDH7A1 and ALDH4A1 structures suggests key interactions that underlie substrate discrimination. Structures of apo ALDH7A1 reveal dramatic conformational differences from the product complex. Product binding is associated with a 16 Å movement of the C-terminus into the active site, which stabilizes the active conformation of the aldehyde substrate anchor loop. The fact that the C-terminus is part of the active site was hitherto unknown. Interestingly, the C-terminus and aldehyde anchor loop are disordered in a new tetragonal crystal form of the apoenzyme, implying that these parts of the enzyme are highly flexible. Our results suggest that the active site of ALDH7A1 is disassembled when the aldehyde site is vacant, and the C-terminus is a mobile element that forms quaternary structural interactions that aid aldehyde binding. These results are relevant to the c.1512delG genetic deletion associated with pyridoxine-dependent epilepsy, which alters the C-terminus of ALDH7A1. PMID:26260980

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

    PubMed

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

    2013-01-01

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

  5. Structure of betaine aldehyde dehydrogenase at 2.1 A resolution.

    PubMed Central

    Johansson, K.; El-Ahmad, M.; Ramaswamy, S.; Hjelmqvist, L.; Jörnvall, H.; Eklund, H.

    1998-01-01

    The three-dimensional structure of betaine aldehyde dehydrogenase, the most abundant aldehyde dehydrogenase (ALDH) of cod liver, has been determined at 2.1 A resolution by the X-ray crystallographic method of molecular replacement. This enzyme represents a novel structure of the highly multiple ALDH, with at least 12 distinct classes in humans. This betaine ALDH of class 9 is different from the two recently determined ALDH structures (classes 2 and 3). Like these, the betaine ALDH structure has three domains, one coenzyme binding domain, one catalytic domain, and one oligomerization domain. Crystals grown in the presence or absence of NAD+ have very similar structures and no significant conformational change occurs upon coenzyme binding. This is probably due to the tight interactions between domains within the subunit and between subunits in the tetramer. The oligomerization domains link the catalytic domains together into two 20-stranded pleated sheet structures. The overall structure is similar to that of the tetrameric bovine class 2 and dimeric rat class 3 ALDH, but the coenzyme binding with the nicotinamide in anti conformation, resembles that of class 2 rather than of class 3. PMID:9792097

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

    SciTech Connect

    Rogers, G.R.; Markova, N.G.; Compton, J.G.

    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.

  7. Ocular Aldehyde Dehydrogenases: Protection against Ultraviolet Damage and Maintenance of Transparency for Vision

    PubMed Central

    Chen, Ying; Thompson, David C.; Koppaka, Vindhya; Jester, James V.; Vasiliou, Vasilis

    2012-01-01

    Aldehyde dehydrogenase (ALDH) enzymes catalyze the NAD(P)+-dependent oxidation of a wide variety of endogenous and exogenous aldehydes to their corresponding acids. Some members of the ALDH superfamily of enzymes are abundantly expressed in the mammalian cornea and lens in a taxon-specific manner. Considered to be corneal and lens crystallins, they confer protective and transparent properties upon these ocular tissues. ALDH3A1 is highly expressed in the cornea of most mammals, with the exception of rabbit that expresses exclusively ALDH1A1 in the cornea. ALDH1A1 is present in both the cornea and lens of several animal species. As a result of their catalytic and non-catalytic functions, ALDH3A1 and ALDH1A1 proteins protect inner ocular tissues from ultraviolet radiation and reactive oxygen-induced damage. In addition, these corneal crystallins contribute to cellular transparency in corneal stromal keratocytes, supporting a structural role of these ALDH proteins. A putative regulatory function of ALDH3A1 on corneal cell proliferation has also been proposed. Finally, the three retinaldehye dehydrogenases cooperatively mediate retinoic acid signaling during the eye development. PMID:23098688

  8. Crystal structure of the NADP+-dependent aldehyde dehydrogenase from Vibrio harveyi: structural implications for cofactor specificity and affinity.

    PubMed Central

    Ahvazi, B; Coulombe, R; Delarge, M; Vedadi, M; Zhang, L; Meighen, E; Vrielink, A

    2000-01-01

    Aldehyde dehydrogenase from the bioluminescent bacterium, Vibrio harveyi, catalyses the oxidation of long-chain aliphatic aldehydes to acids. The enzyme is unique compared with other forms of aldehyde dehydrogenase in that it exhibits a very high specificity and affinity for the cofactor NADP(+). Structural studies of this enzyme and comparisons with other forms of aldehyde dehydrogenase provide the basis for understanding the molecular features that dictate these unique properties and will enhance our understanding of the mechanism of catalysis for this class of enzyme. The X-ray structure of aldehyde dehydrogenase from V. harveyi has been solved to 2.5-A resolution as a partial complex with the cofactor NADP(+) and to 2. 1-A resolution as a fully bound 'holo' complex. The cofactor preference exhibited by different forms of the enzyme is predominantly determined by the electrostatic environment surrounding the 2'-hydroxy or the 2'-phosphate groups of the adenosine ribose moiety of NAD(+) or NADP(+), respectively. In the NADP(+)-dependent structures the presence of a threonine and a lysine contribute to the cofactor specificity. In the V. harveyi enzyme an arginine residue (Arg-210) contributes to the high cofactor affinity through a pi stacking interaction with the adenine ring system of the cofactor. Further differences between the V. harveyi enzyme and other aldehyde dehydrogenases are seen in the active site, in particular a histidine residue which is structurally conserved with phosphorylating glyceraldehyde-3-phosphate dehydrogenase. This may suggest an alternative mechanism for activation of the reactive cysteine residue for nucleophilic attack. PMID:10903148

  9. Characterization of NADP(+)-dependent isocitrate dehydrogenase isozymes from a psychrophilic bacterium, Colwellia psychrerythraea strain 34H.

    PubMed

    Suzuki, Kaori; Takada, Yasuhiro

    2016-08-01

    NADP(+)-dependent isocitrate dehydrogenase (IDH) isozymes of a psychrophilic bacterium, Colwellia psychrerythraea strain 34H, were characterized. The coexistence of monomeric and homodimeric IDHs in this bacterium was confirmed by Western blot analysis, the genes encoding two monomeric (IDH-IIa and IDH-IIb) and one dimeric (IDH-I) IDHs were cloned and overexpressed in Escherichia coli, and the three IDH proteins were purified. Both of the purified IDH-IIa and IDH-IIb were found to be cold-adapted enzymes while the purified IDH-I showed mesophilic properties. However, the specific activities of IDH-IIa and IDH-IIb were lower even at low temperatures than that of IDH-I. Therefore, IDH-I was suggested to be important for the growth of this bacterium. The results of colony formation of E. coli transformants carrying the respective IDH genes and IDH activities in their crude extracts indicated that the expression of the IDH-IIa gene is cold-inducible in the E. coli cells. PMID:27033696

  10. Aldehyde dehydrogenase 2 activation in heart failure restores mitochondrial function and improves ventricular function and remodelling

    PubMed Central

    Gomes, Katia M.S.; Campos, Juliane C.; Bechara, Luiz R.G.; Queliconi, Bruno; Lima, Vanessa M.; Disatnik, Marie-Helene; Magno, Paulo; Chen, Che-Hong; Brum, Patricia C.; Kowaltowski, Alicia J.; Mochly-Rosen, Daria; Ferreira, Julio C.B.

    2014-01-01

    Aims We previously demonstrated that pharmacological activation of mitochondrial aldehyde dehydrogenase 2 (ALDH2) protects the heart against acute ischaemia/reperfusion injury. Here, we determined the benefits of chronic activation of ALDH2 on the progression of heart failure (HF) using a post-myocardial infarction model. Methods and results We showed that a 6-week treatment of myocardial infarction-induced HF rats with a selective ALDH2 activator (Alda-1), starting 4 weeks after myocardial infarction at a time when ventricular remodelling and cardiac dysfunction were present, improved cardiomyocyte shortening, cardiac function, left ventricular compliance and diastolic function under basal conditions, and after isoproterenol stimulation. Importantly, sustained Alda-1 treatment showed no toxicity and promoted a cardiac anti-remodelling effect by suppressing myocardial hypertrophy and fibrosis. Moreover, accumulation of 4-hydroxynonenal (4-HNE)-protein adducts and protein carbonyls seen in HF was not observed in Alda-1-treated rats, suggesting that increasing the activity of ALDH2 contributes to the reduction of aldehydic load in failing hearts. ALDH2 activation was associated with improved mitochondrial function, including elevated mitochondrial respiratory control ratios and reduced H2O2 release. Importantly, selective ALDH2 activation decreased mitochondrial Ca2+-induced permeability transition and cytochrome c release in failing hearts. Further supporting a mitochondrial mechanism for ALDH2, Alda-1 treatment preserved mitochondrial function upon in vitro aldehydic load. Conclusions Selective activation of mitochondrial ALDH2 is sufficient to improve the HF outcome by reducing the toxic effects of aldehydic overload on mitochondrial bioenergetics and reactive oxygen species generation, suggesting that ALDH2 activators, such as Alda-1, have a potential therapeutic value for treating HF patients. PMID:24817685

  11. NAD(P)-Dependent Aldehyde Dehydrogenases Induced during Growth of Ralstonia eutropha Strain Bo on Tetrahydrofurfuryl Alcohol

    PubMed Central

    Schräder, Thomas; Zarnt, Grit; Andreesen, Jan R.

    2001-01-01

    Different aldehyde dehydrogenases (AlDHs) were formed during growth of Ralstonia eutropha Bo on tetrahydrofurfuryl alcohol (THFA). One of these enzymes, AlDH 4, was purified and characterized as a homodimer containing no prosthetic groups, showing a strong substrate inhibition, and having an N-terminal sequence similar to those of various NAD(P)-dependent AlDHs. The conversion rate of THFA by the quinohemoprotein THFA dehydrogenase was increased by AlDH 4. PMID:11717302

  12. Aldehyde Dehydrogenase 2 Has Cardioprotective Effects on Myocardial Ischaemia/Reperfusion Injury via Suppressing Mitophagy

    PubMed Central

    Ji, Wenqing; Wei, Shujian; Hao, Panpan; Xing, Junhui; Yuan, Qiuhuan; Wang, Jiali; Xu, Feng; Chen, Yuguo

    2016-01-01

    Mitophagy, a selective form of autophagy, is excessively activated in myocardial ischemia/reperfusion (I/R). The study investigated whether aldehyde dehydrogenase 2 (ALDH2) exerted its cardioprotective effect by regulating mitophagy. Myocardial infarct size and apoptosis after I/R in rats were ameliorated by Alda-1, an ALDH2 activator, and aggravated by ALDH2 inhibition. Both in I/R rats and hypoxia/reoxygenation H9C2 cells, ALDH2 activation suppressed phosphatase and tensin homolog-induced putative kinase 1 (PINK1)/Parkin expression, regulating mitophagy, by preventing 4-hydroxynonenal, reactive oxygen species and mitochondrial superoxide accumulation. Furthermore, the effect was enhanced by ALDH2 inhibition. Thus, ALDH2 may protect hearts against I/R injury by suppressing PINK1/Parkin–dependent mitophagy. PMID:27148058

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

    PubMed

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

    2014-01-01

    Aldehyde dehydrogenase 1 (ALDH1) is reported as a biomarker for identifying some cancer stem cells, and down-regulation or inhibition of the enzyme can be effective in anti-drug resistance and a potent therapeutic for some tumours. In this paper, the inhibitory activity, mechanism mode, molecular docking and 3D-QSAR (three-dimensional quantitative structure activity relationship) of curcumin analogues (CAs) against ALDH1 were studied. Results demonstrated that curcumin and CAs possessed potent inhibitory activity against ALDH1, and the CAs compound with ortho di-hydroxyl groups showed the most potent inhibitory activity. This study indicates that CAs may represent a new class of ALDH1 inhibitor. PMID:24840575

  14. Aldehyde Dehydrogenase 1a1 Mediates a GABA Synthesis Pathway in Midbrain Dopaminergic Neurons

    PubMed Central

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

    2016-01-01

    Midbrain dopamine neurons are an essential component of the basal ganglia circuitry, playing key roles in the control of fine movement and reward. Recently, it has been demonstrated that γ-aminobutyric acid (GABA), the chief inhibitory neurotransmitter, is co-released by dopamine neurons. Here we show that GABA corelease in dopamine neurons does not utilize the conventional GABA synthesizing enzymes, glutamate decarboxylases GAD65 and GAD67. Our experiments reveal an evolutionarily conserved GABA synthesis pathway mediated by aldehyde dehydrogenase 1a1 (ALDH1a1). Moreover, GABA co-release is modulated by ethanol at binge drinking blood alcohol concentrations and diminished ALDH1a1 leads to enhanced alcohol consumption and preference. These findings provide insights into the functional role of GABA co-release in midbrain dopamine neurons, which may be essential for reward-based behavior and addiction. PMID:26430123

  15. Azotobacter vinelandii Aldehyde Dehydrogenase Regulated by ς54: Role in Alcohol Catabolism and Encystment

    PubMed Central

    Gama-Castro, Socorro; Núñez, Cinthia; Segura, Daniel; Moreno, Soledad; Guzmán, Josefina; Espín, Guadalupe

    2001-01-01

    Encystment in Azotobacter vinelandii is induced by n-butanol or β-hydroxybutyrate (BHB). We identified a gene, encoding an aldehyde dehydrogenase, that was named aldA. An aldA mutation impaired bacterial growth on n-butanol, ethanol, or hexanol as the sole carbon source. Expression of aldA increased in cells shifted from sucrose to n-butanol and was shown to be dependent on the alternative ς54 factor. A mutation in rpoN encoding the ς54 factor also impaired growth on alcohols. Encystment on n-butanol, but not on BHB, was impaired in aldA or rpoN mutants, indicating that n-butanol is not an inducer of encystment by itself but must be catabolized in order to induce encystment. PMID:11591659

  16. A Personalized Medicine Approach for Asian Americans with the Aldehyde Dehydrogenase 2*2 Variant

    PubMed Central

    Gross, Eric R.; Zambelli, Vanessa O.; Small, Bryce A.; Ferreira, Julio C.B.; Chen, Che-Hong; Mochly-Rosen, Daria

    2015-01-01

    Asian Americans are one of the fastest-growing populations in the United States. A relatively large subset of this population carries a unique loss-of-function point mutation in aldehyde dehydrogenase 2 (ALDH2), ALDH2*2. Found in approximately 560 million people of East Asian descent, ALDH2*2 reduces enzymatic activity by approximately 60% to 80% in heterozygotes. Furthermore, this variant is associated with a higher risk for several diseases affecting many organ systems, including a particularly high incidence relative to the general population of esophageal cancer, myocardial infarction, and osteoporosis. In this review, we discuss the pathophysiology associated with the ALDH2*2 variant, describe why this variant needs to be considered when selecting drug treatments, and suggest a personalized medicine approach for Asian American carriers of this variant. We also discuss future clinical and translational perspectives regarding ALDH2*2 research. PMID:25292432

  17. IN VITRO ORGANIC NITRATE BIOACTIVATION TO NITRIC OXIDE BY RECOMBINANT ALDEHYDE DEHYDROGENASE 3A1

    PubMed Central

    Lin, Shunxin; Page, Nathaniel A.; Fung, Sun Mi; Fung, Ho-Leung

    2013-01-01

    Organic nitrates (ORNs) are commonly used anti-ischemic and anti-anginal agents, which serve as an exogenous source of the potent vasodilator nitric oxide (NO). Recently, both mitochondrial aldehyde dehydrogenase-2 (ALDH2) and cytosolic aldehyde dehydrogenase-1a1 (ALDH1A1) have been shown to exhibit the ability to selectively bioactivate various ORNs in vitro. The objective of the present research was to examine the potential role of ALDH3A1, another major cytosolic isoform of ALDH, in the in vitro bioactivation of various ORNs, and to estimate the enzyme kinetic parameters toward ORNs through mechanistic modeling. The extent of bioactivation was assayed by exposing recombinant ALDH3A1 to various concentrations of ORNs, and measuring the concentration-time profiles of released NO via a NO-specific electrode. Metabolite formation kinetics was monitored for nitroglycerin (NTG) using LC/MS/MS. Our results showed that ALDH3A1 mRNA and protein were highly expressed in C57BL/6 mouse aortic, cardiac, and hepatic tissues, and it was able to release NO from several ORNs, including NTG, isosorbide dinitrate (ISDN), isosorbide-2-mononitrate (IS-2-MN), and nicorandil with similar Vmax (0.175 – 0.503 nmol/min/mg of ALDH3A1), and Km values of 4.01, 46.5, 818 and 5.75 × 103 μM respectively. However, activation of isosorbide-5-mononitrate (IS-5-MN) by ALDH3A1 was undetectable in vitro. ALDH3A1 was also shown to denitrate NTG, producing primarily glyceryl 1, 2-dinitrate (1, 2-GDN) in preference to glyceryl 1, 3-dinitrate (1, 3-GDN). Therefore, ALDH3A1 may contribute to the bioactivation of ORNs in vivo. PMID:24126018

  18. Mitochondrial NAD Dependent Aldehyde Dehydrogenase either from Yeast or Human Replaces Yeast Cytoplasmic NADP Dependent Aldehyde Dehydrogenase for the Aerobic Growth of Yeast on Ethanol

    PubMed Central

    Mukhopadhyay, Abhijit; Wei, Baoxian; Weiner, Henry

    2013-01-01

    Background In a previous study, we deleted three aldehyde dehydrogenase (ALDH) genes, involved in ethanol metabolism, from yeast S. cerevisiae and found that the triple deleted yeast strain did not grow on ethanol as sole carbon source. The ALDHs were NADP dependent cytosolic ALDH1, NAD dependent mitochondrial ALDH2 and NAD/NADP dependent mitochondrial ALDH5. Double deleted strain ΔALDH2+ΔALDH5 or ΔALDH1+ΔALDH5 could grow on ethanol. However, the double deleted strain ΔALDH1+ΔALDH2 did not grow in ethanol. Methods Triple deleted yeast strain was used. Mitochondrial NAD dependent ALDH from yeast or human was placed in yeast cytosol. Results In the present study we found that a mutant form of cytoplasmic ALDH1 with very low activity barely supported the growth of the triple deleted strain (ΔALDH1+ΔALDH2+ΔALDH5) on ethanol. Finding the importance of NADP dependent ALDH1 on the growth of the strain on ethanol we examined if NAD dependent mitochondrial ALDH2 either from yeast or human would be able to support the growth of the triple deleted strain on ethanol if the mitochondrial form was placed in cytosol. We found that the NAD dependent mitochondrial ALDH2 from yeast or human was active in cytosol and supported the growth of the triple deleted strain on ethanol. Conclusion This study showed that coenzyme preference of ALDH is not critical in cytosol of yeast for the growth on ethanol. PMID:23454351

  19. Betaine Accumulation and Betaine-Aldehyde Dehydrogenase in Spinach Leaves 1

    PubMed Central

    Pan, Shu-Mei; Moreau, Robert A.; Yu, Charles; Huang, Anthony H. C.

    1981-01-01

    Spinach leaf discs accumulated betaine when exposed to a mannitol solution of −20 bars. The accumulation was 12 micromoles per gram original fresh weight in a 24-hour period. Betaine-aldehyde dehydrogenase (EC 1.2.1.8) was assayed in various subcellular fractions prepared from spinach leaves, and it was found only in the soluble fraction. This cytosolic enzyme was purified 175-fold, and its properties were studied. The enzyme was relatively specific for betaine aldehyde as the substrate with an apparent Km value of 2.08 × 10−4 molar. It also exerted activity on other aldehyde analogs tested, but with lower Vmax and higher Km values. The enzyme was relatively specific for nicotinamide adenine dinucleotide as the coenzyme, having an apparent Km value of 9.46 × 10−6 molar; lower activities were observed when nicotinamide adenine dinucleotide phosphate or 3-acetyl pyridine adenine dinucleotide were tested as electron acceptors. The activity was enhanced by dithiothreitol and inhibited by p-chloromercuribenzoate, and the inhibition by p-chloromercuribenzoate was partially reversed by the subsequent addition of dithiothreitol. The activity was inhibited by high concentrations of NaCl and, to a lesser extent, proline. The equilibrium of the enzymic reaction was strongly in favor of betaine formation. The in vitro activity of the enzyme under optimal assay conditions was high enough to account for the amount of betaine accumulated under water stress conditions. The enzyme activity was the same in unstressed leaves and in leaves that had been water stressed for 24 hours. PMID:16661818

  20. Alda-1 is an agonist and chemical chaperone for the common human aldehyde dehydrogenase 2 variant

    SciTech Connect

    Perez-Miller, Samantha; Younus, Hina; Vanam, Ram; Chen, Che-Hong; Mochly-Rosen, Daria; Hurley, Thomas D.

    2010-04-19

    In approximately one billion people, a point mutation inactivates a key detoxifying enzyme, aldehyde dehydrogenase (ALDH2). This mitochondrial enzyme metabolizes toxic biogenic and environmental aldehydes, including the endogenously produced 4-hydroxynonenal (4HNE) and the environmental pollutant acrolein, and also bioactivates nitroglycerin. ALDH2 is best known, however, for its role in ethanol metabolism. The accumulation of acetaldehyde following the consumption of even a single alcoholic beverage leads to the Asian alcohol-induced flushing syndrome in ALDH2*2 homozygotes. The ALDH2*2 allele is semidominant, and heterozygotic individuals show a similar but less severe phenotype. We recently identified a small molecule, Alda-1, that activates wild-type ALDH2 and restores near-wild-type activity to ALDH2*2. The structures of Alda-1 bound to ALDH2 and ALDH2*2 reveal how Alda-1 activates the wild-type enzyme and how it restores the activity of ALDH2*2 by acting as a structural chaperone.

  1. Inhibition of mitochondrial aldehyde dehydrogenase by nitric oxide-mediated S-nitrosylation

    PubMed Central

    Moon, Kwan-Hoon; Kim, Bong-Jo; Song, Byoung J.

    2005-01-01

    Mitochondrial aldehyde dehydrogenase (ALDH2) is responsible for the metabolism of acetaldehyde and other toxic lipid aldehydes. Despite many reports about the inhibition of ALDH2 by toxic chemicals, it is unknown whether nitric oxide (NO) can alter the ALDH2 activity in intact cells or in vivo animals. The aim of this study was to investigate the effects of NO on ALDH2 activity in H4IIE-C3 rat hepatoma cells. NO donors such as S-nitrosoglutathione (GSNO), S-nitroso-N-acetylpenicillamine, and 3-morpholinosydnonimine significantly increased the nitrite concentration while they inhibited the ALDH2 activity. Addition of GSH-ethylester (GSH-EE) completely blocked the GSNO-mediated ALDH2 inhibition and increased nitrite concentration. To directly demonstrate the NO-mediated S-nitrosylation and inactivation, ALDH2 was immunopurified from control or GSNO-treated cells and subjected to immunoblot analysis. The anti-nitrosocysteine antibody recognized the immunopurified ALDH2 only from the GSNO-treated samples. All these results indicate that S-nitrosylation of ALDH2 in intact cells leads to reversible inhibition of ALDH2 activity. PMID:16242127

  2. The short-chain alcohol dehydrogenase ABA2 catalyzes the conversion of xanthoxin to abscisic aldehyde.

    PubMed

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

    2002-08-01

    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 K(m) value for xanthoxin of 19 micro M 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

  3. Gene structure and chromosomal localization of the human HSD11K gene encoding the kidney (type 2) isozyme of 11{beta}-hydroxysteroid dehydrogenase

    SciTech Connect

    Agarwal, A.K.; Rogerson, F.M.; Mune, T.; White, P.C.

    1995-09-01

    11{beta}-hydroxysteroid dehydrogenase (11{beta}HSD) converts glucocorticoids to inactive products and is thus thought to confer specificity for aldosterone on the type I mineralocorticoid receptor in the kidney. Recent studies indicate the presence of at least two isozymes of 11{beta}HSD. In vitro, the NAD{sup +}-dependent kidney (type 2) isozyme catalyzes 11{beta}-dehydrogenase but not reductase reactions, whereas the NADP{sup +}-dependent liver (type 1) isozyme catalyzes both reactions. We have now characterized the human gene encoding kidney 11{beta}HSD (HSD11K). A bacteriophage P1 clone was isolated after screening a human genomic library by hybridization with sheep HSD11K cDNA. The gene consists of 5 exons spread over 6 kb. The nucleotide binding domain lies in the first exon are GC-rich (80%), suggesting that the gene may be transcriptionally regulated by factors that recognize GC-rich sequences. Fluorescence in situ hybridization of metaphase chromosomes with a positive P1 clone localized the gene to chromosome 16q22. In contrast, the HSD11L (liver isozyme) gene is located on chromosome 1 and contains 6 exons; the coding sequences of these genes are only 21% identical. HSD11K is expressed at high levels in the placenta and kidney of midgestation human fetuses and at lower levels in lung and testes. Different transcriptional start sites are utilized in kidney and placenta. These data should be applicable to genetic analysis of the syndrome of apparent mineralocorticoid excess, which may represent a deficiency of 11{beta}HSD. 25 refs., 5 figs.

  4. Human Aldehyde Dehydrogenase Genes: Alternatively-Spliced Transcriptional Variants and Their Suggested Nomenclature

    PubMed Central

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

    2011-01-01

    OBJECTIVE 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. METHODS Data-mining methods were used to retrieve all human ALDH sequences. Alternatively-spliced transcriptional variants were determined based upon: a) criteria for sequence integrity and genomic alignment; b) evidence of multiple independent cDNA sequences corresponding to a variant sequence; and c) if available, empirical evidence of variants from the literature. RESULTS AND CONCLUSION 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. In order 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. PMID:19823103

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

    PubMed Central

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

    2015-01-01

    Aldehyde dehydrogenases (ALDHs) constitute a superfamily of NAD(P)+-dependent enzymes that catalyze the irreversible oxidation of a wide range of reactive aldehydes to their corresponding nontoxic carboxylic acids. ALDHs have been studied in many organisms from bacteria to mammals; however, no systematic analyses incorporating genome organization, gene structure, expression profiles, and cis-acting elements have been conducted in the model tree species Populus trichocarpa thus far. In this study, a comprehensive analysis of the Populus ALDH gene superfamily was performed. A total of 26 Populus ALDH genes were found to be distributed across 12 chromosomes. Genomic organization analysis indicated that purifying selection may have played a pivotal role in the retention and maintenance of PtALDH gene families. The exon-intron organizations of PtALDHs were highly conserved within the same family, suggesting that the members of the same family also may have conserved functionalities. Microarray data and qRT-PCR analysis indicated that most PtALDHs had distinct tissue-specific expression patterns. The specificity of cis-acting elements in the promoter regions of the PtALDHs and the divergence of expression patterns between nine paralogous PtALDH gene pairs suggested that gene duplications may have freed the duplicate genes from the functional constraints. The expression levels of some ALDHs were up- or down-regulated by various abiotic stresses, implying that the products of these genes may be involved in the adaptation of Populus to abiotic stresses. Overall, the data obtained from our investigation contribute to a better understanding of the complexity of the Populus ALDH gene superfamily and provide insights into the function and evolution of ALDH gene families in vascular plants. PMID:25909656

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

    PubMed Central

    Ikeda, Tetsuhiko; Takahashi, Tetsuya; Tsujita, Mika; Kanazawa, Masato; Toriyabe, Masafumi; Koyama, Misaki; Itoh, Kosuke; Nakada, Tsutomu; Nishizawa, Masatoyo; Shimohata, Takayoshi

    2015-01-01

    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. PMID:26083658

  7. Metabolic basis of ethylene glycol monobutyl ether (2-butoxyethanol) toxicity: role of alcohol and aldehyde dehydrogenases

    SciTech Connect

    Ghanayem, B.I.; Burka, L.T.; Matthews, H.B.

    1987-07-01

    2-Butoxyethanol (BE) is a massively produced glycol ether of which more than 230 million pounds was produced in the United States in 1983. It is extensively used in aerosols and cleaning agents intended for household use. This creates a high potential for human exposure during its manufacturing and use. A single exposure of rats to BE causes severe hemolytic anemia accompanied by secondary hemoglobinuria as well as liver and kidney damage. Butoxyacetic acid (BAA) was earlier identified as a urinary metabolite of BE. In addition, we have recently identified two additional urinary metabolites of BE, namely, BE-glucuronide and BE-sulfate conjugates. The current studies were undertaken to investigate the metabolic basis of BE-induced hematotoxicity in male F344 rats. Treatment of rats with pyrazole (alcohol dehydrogenase inhibitor) protected rats against BE-induced hematotoxicity and inhibited BE metabolism to BAA. Pyrazole inhibition of BE metabolism to BAA was accompanied by increased BE metabolism to BE-glucuronide and BE-sulfate as determined by quantitative high-performance liquid chromatography analysis of BE metabolites in urine. There was approximately a 10-fold decrease in the ratio of BAA to BE-glucuronide + BE-sulfate in the urine of rats treated with pyrazole + BE compared to rats treated with BE alone. Pretreatment of rats with cyanamide (aldehyde dehydrogenase inhibitor) also significantly protected rats against BE-induced hematotoxicity and modified BE metabolism in a manner similar to that caused by pyrazole. Administration of equimolar doses of BE, the metabolic intermediate butoxyacetaldehyde, or the ultimate metabolite BAA caused similar hematotoxic effects. Cyanamide also protected rats against butoxyacetaldehyde-induced hematotoxicity.

  8. Geometric specificity of alcohol dehydrogenases and its potential for separation of trans and cis isomers of unsaturated aldehydes.

    PubMed Central

    Klibanov, A M; Giannousis, P P

    1982-01-01

    The geometric specificity of three different alcohol dehydrogenases (alcohol:NAD+ oxidoreductase, EC 1.1.1.1) (from yeast, from horse liver, and from Leuconostoc mesenteroides) in the reduction of trans- and cis-cinnamaldehydes has been investigated. All three enzymes display a remarkable trans specificity: they react with the trans isomer 7 to 647 times faster than with its cis counterpart. Experiments with the enzymatic reduction of 3-phenylpropionaldehyde, a saturated analog of cinnamaldehyde, have revealed that whereas trans-cinnamaldehyde possesses the "right" configuration for the active centers of the alcohol dehydrogenases, the cis isomer apparently does not fit the active centers well. All three alcohol dehydrogenases studied also exhibit a marked trans specificity in the reaction with alpha-methylcinnamaldehyde. The geometric specificity of alcohol dehydrogenases can be used for the production of otherwise hard to synthesize cis isomers of unsaturated aldehydes from their readily available trans counterparts: trans-cinnamaldehyde was irradiated with ultraviolet light (which converted it to a mixture of trans and cis isomers) then treated with NADH and yeast alcohol dehydrogenase (which selectively reduces only trans aldehyde into the alcohol), and finally the mixture of cis-cinnamaldehyde and trans-cinnamyl alcohol was separated easily by preparative column chromatography. PMID:7048306

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

    PubMed Central

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

    2009-01-01

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

  10. Aldehyde Dehydrogenase Expression Drives Human Regulatory T Cell Resistance to Posttransplantation Cyclophosphamide

    PubMed Central

    Kanakry, Christopher G.; Ganguly, Sudipto; Zahurak, Marianna; Bolaños-Meade, Javier; Thoburn, Christopher; Perkins, Brandy; Fuchs, Ephraim J.; Jones, Richard J.; Hess, Allan D.; Luznik, Leo

    2014-01-01

    High-dose, posttransplantation cyclophosphamide (PTCy) is an effective strategy for preventing graft-versus-host disease (GVHD) after allogeneic blood or marrow transplantation (alloBMT). However, the mechanisms by which PTCy modulates alloimmune responses are not well understood. We studied early T cell reconstitution in patients undergoing alloBMT with PTCy and the effects of mafosfamide, a cyclophosphamide (Cy) analog, on CD4+ T cells in allogeneic mixed lymphocyte reactions (MLRs) in vitro. Patients exhibited reductions in naïve, potentially alloreactive conventional CD4+ T cells with relative preservation of memory CD4+Foxp3+ T cells. In particular, CD4+CD45RA−Foxp3+hi effector regulatory T cells (Tregs) recovered rapidly after alloBMT and, unexpectedly, were present at higher levels in patients with GVHD. CD4+Foxp3+ T cells from patients and from allogeneic MLRs expressed relatively high levels of aldehyde dehydrogenase (ALDH), the major in vivo mechanism of Cy resistance. Treatment of MLR cultures with the ALDH inhibitor diethylaminobenzaldehyde reduced the activation and proliferation of CD4+ T cells and sensitized Tregs to mafosfamide. Finally, removing Tregs from peripheral blood lymphocyte grafts obviated PTCy's GVHD-protective effect in a xenogeneic transplant model. Together, these findings suggest that Treg resistance to Cy through expression of ALDH may contribute to the clinical activity of PTCy in preventing GVHD. PMID:24225944

  11. Rotenone Decreases Intracellular Aldehyde Dehydrogenase Activity: Implications for the Pathogenesis of Parkinson Disease

    PubMed Central

    Goldstein, David S.; Sullivan, Patti; Cooney, Adele; Jinsmaa, Yunden; Kopin, Irwin J.; Sharabi, Yehonatan

    2015-01-01

    Repeated systemic administration of the mitochondrial complex I inhibitor rotenone produces a rodent model of Parkinson disease (PD). Mechanisms of relatively selective rotenone-induced damage to nigrostriatal dopaminergic neurons remain incompletely understood. According to the “catecholaldehyde hypothesis,” buildup of the autotoxic dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL) contributes to PD pathogenesis. Vesicular uptake blockade increases DOPAL levels, and DOPAL is detoxified mainly by aldehyde dehydrogenase (ALDH). We tested whether rotenone interferes with vesicular uptake and intracellular ALDH activity. Endogenous and F-labeled catechols were measured in PC12 cells incubated with rotenone (0-1000 nM, 180 minutes), without or with F-dopamine (2 μM) to track vesicular uptake and catecholamine metabolism. Rotenone dose-dependently increased DOPAL, F-DOPAL, and 3,4-dihydroxyphenylethanol (DOPET) levels while decreasing dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) levels and the ratio of dopamine to the sum of its deaminated metabolites. In test tubes, rotenone did not affect conversion of DOPAL to DOPAC by ALDH when NAD+ was supplied, whereas the direct-acting ALDH inhibitor benomyl markedly increased DOPAL and decreased DOPAC concentrations in the reaction mixtures. We propose that rotenone builds up intracellular DOPAL by decreasing ALDH activity and attenuating vesicular sequestration of cytoplasmic catecholamines. The results provide a novel mechanism for selective rotenone-induced toxicity in dopaminergic neurons. PMID:25645689

  12. Effect of various chemicals on the aldehyde dehydrogenase activity of the rat liver cytosol.

    PubMed

    Marselos, M; Vasiliou, V

    1991-01-01

    The cytosolic activity of aldehyde dehydrogenase (ALDH) was studied in the rat liver, after acute administration of various carcinogenic and chemically related compounds. Male Wistar rats were treated with 27 different chemicals, including polycyclic aromatic hydrocarbons, aromatic amines, nitrosamines, azo dyes, as well as with some known direct-acting carcinogens. The cytosolic ALDH activity of the liver was determined either with propionaldehyde and NAD (P/NAD), or with benzaldehyde and NADP (B/NADP). The activity of ALDH remained unaffected after treatment with 1-naphthylamine, nitrosamines and also with the direct-acting chemical carcinogens tested. On the contrary, polycyclic aromatic hydrocarbons, polychlorinated biphenyls (Arochlor 1254) and 2-naphthylamine produced a remarkable increase of ALDH. In general, the response to the effectors was disproportionate between the two types of enzyme activity, being much in favour for the B/NADP activity. This fact resulted to an inversion of the ratio B/NADP vs. P/NAD, which under constitutive conditions is lower than 1. In this respect, the most potent compounds were found to be polychlorinated biphenyls, 3-methylcholanthrene, benzo(a)pyrene and 1,2,5,6-dibenzoanthracene. Our results suggest that the B/NADP activity of the soluble ALDH is greatly induced after treatment with compounds possessing aromatic ring(s) in their molecule. It is not known, if this response of the hepatocytes is related with the process of chemical carcinogenesis. PMID:2060039

  13. Aldehyde Dehydrogenase Activity Identifies a Population of Human Skeletal Muscle Cells With High Myogenic Capacities

    PubMed Central

    Vauchez, Karine; Marolleau, Jean-Pierre; Schmid, Michel; Khattar, Patricia; Chapel, Alain; Catelain, Cyril; Lecourt, Séverine; Larghéro, Jérôme; Fiszman, Marc; Vilquin, Jean-Thomas

    2009-01-01

    Aldehyde dehydrogenase 1A1 (ALDH) activity is one hallmark of human bone marrow (BM), umbilical cord blood (UCB), and peripheral blood (PB) primitive progenitors presenting high reconstitution capacities in vivo. In this study, we have identified ALDH+ cells within human skeletal muscles, and have analyzed their phenotypical and functional characteristics. Immunohistofluorescence analysis of human muscle tissue sections revealed rare endomysial cells. Flow cytometry analysis using the fluorescent substrate of ALDH, Aldefluor, identified brightly stained (ALDHbr) cells with low side scatter (SSClo), in enzymatically dissociated muscle biopsies, thereafter abbreviated as SMALD+ (for skeletal muscle ALDH+) cells. Phenotypical analysis discriminated two sub-populations according to CD34 expression: SMALD+/CD34− and SMALD+/CD34+ cells. These sub-populations did not initially express endothelial (CD31), hematopoietic (CD45), and myogenic (CD56) markers. Upon sorting, however, whereas SMALD+/CD34+ cells developed in vitro as a heterogeneous population of CD56− cells able to differentiate in adipoblasts, the SMALD+/CD34− fraction developed in vitro as a highly enriched population of CD56+ myoblasts able to form myotubes. Moreover, only the SMALD+/CD34− population maintained a strong myogenic potential in vivo upon intramuscular transplantation. Our results suggest that ALDH activity is a novel marker for a population of new human skeletal muscle progenitors presenting a potential for cell biology and cell therapy. PMID:19738599

  14. Aldehyde dehydrogenase 2 is associated with cognitive functions in patients with Parkinson’s disease

    PubMed Central

    Yu, Rwei-Ling; Tan, Chun-Hsiang; Lu, Ying-Che; Wu, Ruey-Meei

    2016-01-01

    Neurotransmitter degradation has been proposed to cause the accumulation of neurotoxic metabolites. The metabolism of these metabolites involves aldehyde dehydrogenase 2 (ALDH2). The Asian-specific single nucleotide polymorphism rs671 causes reduced enzyme activity. This study aims to explore whether Parkinson’s disease (PD) patients with reduced ALDH2 activity owing to the rs671 polymorphism are at risk for neuropsychological impairments. A total of 139 PD patients were recruited. Each participant was assessed for medical characteristics and their ALDH2 genotype. The Mini-Mental State Examination (MMSE), the Clinical Dementia Rating Scale and the Frontal Behavioral Inventory were used to measure neuropsychological functions. We found that the MMSE scores were significantly lower in patients with inactive ALDH2 (U = 1873.5, p = 0.02). The presence of cognitive impairments was significantly more frequent in the inactive ALDH2 group (46.0%) than in the active ALDH2 group (26.3%) (χ2 = 5.886, p = 0.01). The inactive group showed significant deterioration in hobbies and exhibited more severe “disorganization” and “hyper-sexuality” behaviours. The additive effects of the allele on the development of cognitive impairments in PD patients may be an important finding that provides further insight into the pathogenic mechanism of cognitive dysfunction in PD. PMID:27453488

  15. Aldehyde dehydrogenase 1a3 defines a subset of failing pancreatic β cells in diabetic mice.

    PubMed

    Kim-Muller, Ja Young; Fan, Jason; Kim, Young Jung R; Lee, Seung-Ah; Ishida, Emi; Blaner, William S; Accili, Domenico

    2016-01-01

    Insulin-producing β cells become dedifferentiated during diabetes progression. An impaired ability to select substrates for oxidative phosphorylation, or metabolic inflexibility, initiates progression from β-cell dysfunction to β-cell dedifferentiation. The identification of pathways involved in dedifferentiation may provide clues to its reversal. Here we isolate and functionally characterize failing β cells from various experimental models of diabetes and report a striking enrichment in the expression of aldehyde dehydrogenase 1 isoform A3 (ALDH(+)) as β cells become dedifferentiated. Flow-sorted ALDH(+) islet cells demonstrate impaired glucose-induced insulin secretion, are depleted of Foxo1 and MafA, and include a Neurogenin3-positive subset. RNA sequencing analysis demonstrates that ALDH(+) cells are characterized by: (i) impaired oxidative phosphorylation and mitochondrial complex I, IV and V; (ii) activated RICTOR; and (iii) progenitor cell markers. We propose that impaired mitochondrial function marks the progression from metabolic inflexibility to dedifferentiation in the natural history of β-cell failure. PMID:27572106

  16. High current density PQQ-dependent alcohol and aldehyde dehydrogenase bioanodes.

    PubMed

    Aquino Neto, Sidney; Hickey, David P; Milton, Ross D; De Andrade, Adalgisa R; Minteer, Shelley D

    2015-10-15

    In this paper, we explore the bioelectrooxidation of ethanol using pyrroloquinoline quinone (PQQ)-dependent alcohol and aldehyde dehydrogenase (ADH and AldDH) enzymes for biofuel cell applications. The bioanode architectures were designed with both direct electron transfer (DET) and mediated electron transfer (MET) mechanisms employing high surface area materials such as multi-walled carbon nanotubes (MWCNTs) and MWCNT-decorated gold nanoparticles, along with different immobilization techniques. Three different polymeric matrices were tested (tetrabutyl ammonium bromide (TBAB)-modified Nafion; octyl-modified linear polyethyleneimine (C8-LPEI); and cellulose) in the DET studies. The modified Nafion membrane provided the best electrical communication between enzymes and the electrode surface, with catalytic currents as high as 16.8 ± 2.1 µA cm(-2). Then, a series of ferrocene redox polymers were evaluated for MET. The redox polymer 1,1'-dimethylferrocene-modified linear polyethyleneimine (FcMe2-C3-LPEI) provided the best electrochemical response. Using this polymer, the electrochemical assays conducted in the presence of MWCNTs and MWCNTs-Au indicated a Jmax of 781 ± 59 µA cm(-2) and 925 ± 68 µA cm(-2), respectively. Overall, from the results obtained here, DET using the PQQ-dependent ADH and AldDH still lacks high current density, while the bioanodes that operate via MET employing ferrocene-modified LPEI redox polymers show efficient energy conversion capability in ethanol/air biofuel cells. PMID:25988787

  17. Aldehyde dehydrogenase variation enhances effect of pesticides associated with Parkinson disease

    PubMed Central

    Fitzmaurice, Arthur G.; Rhodes, Shannon L.; Cockburn, Myles; Ritz, Beate

    2014-01-01

    Objective: The objective of this study was to determine whether environmental and genetic alterations of neuronal aldehyde dehydrogenase (ALDH) enzymes were associated with increased Parkinson disease (PD) risk in an epidemiologic study. Methods: A novel ex vivo assay was developed to identify pesticides that can inhibit neuronal ALDH activity. These were investigated for PD associations in a population-based case-control study, the Parkinson's Environment & Genes (PEG) Study. Common variants in the mitochondrial ALDH2 gene were genotyped to assess effect measure modification (statistical interaction) of the pesticide effects by genetic variation. Results: All of the metal-coordinating dithiocarbamates tested (e.g., maneb, ziram), 2 imidazoles (benomyl, triflumizole), 2 dicarboxymides (captan, folpet), and 1 organochlorine (dieldrin) inhibited ALDH activity, potentially via metabolic byproducts (e.g., carbon disulfide, thiophosgene). Fifteen screened pesticides did not inhibit ALDH. Exposures to ALDH-inhibiting pesticides were associated with 2- to 6-fold increases in PD risk; genetic variation in ALDH2 exacerbated PD risk in subjects exposed to ALDH-inhibiting pesticides. Conclusion: ALDH inhibition appears to be an important mechanism through which environmental toxicants contribute to PD pathogenesis, especially in genetically vulnerable individuals, suggesting several potential interventions to reduce PD occurrence or slow or reverse its progression. PMID:24491970

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

    SciTech Connect

    Nakamura, Tomofumi; Ichinose, Hirofumi; Wariishi, Hiroyuki

    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.

  19. Heterologous Expression of Aldehyde Dehydrogenase from Saccharomyces cerevisiae in Klebsiella pneumoniae for 3-Hydroxypropionic Acid Production from Glycerol.

    PubMed

    Wang, Kang; Wang, Xi; Ge, Xizhen; Tian, Pingfang

    2012-09-01

    3-Hydroxypropionic acid (3-HP) is a commercially valuable platform compound. Klebsiella pneumoniae has been concerned as an appropriate host for 3-HP production because of its robust capacity to metabolize glycerol. Glycerol conversion to 3-HP in K. pneumoniae comprises two successive reactions: glycerol dehydratase catalyzes glycerol to 3-hydroxypropionaldehyde (3-HPA); aldehyde dehydrogenase catalyzes 3-HPA to 3-HP. Previous studies focusing on inducible expression of aldehyde dehydrogenase have shown defects of high cost of inducer and low catalytic activity due to inclusion body. Here we show a different strategy that a native promoter in the host K. pneumoniae was used to drive the heterologous expression of aldehyde dehydrogenase gene ald4 from Saccharomyces cerevisiae. The 3-HP yield of the recombinant reached a peak of 4.23 g/L at log phase, but it decreased during later period of fermentation. Except the validation of high activity of ald4, particularly, the 3-HP formation was uncovered to be closely coupled with cell division, and the lacking of NAD and ATP at latter fermentation phase became the bottleneck for cell growth and 3-HP accumulation. Furthermore, 3-HP is postulated to be converted to 3-HPA via feedback inhibition or other metabolite via unknown mechanism. Since glycerol dissimilation is a common mechanism in a variety of bacteria, the expression strategy using native promoter and implications may provide significant insight into the metabolic engineering for 3-HP production. PMID:23997342

  20. Structural shifts of aldehyde dehydrogenase enzymes were instrumental for the early evolution of retinoid-dependent axial patterning in metazoans.

    PubMed

    Sobreira, Tiago J P; Marlétaz, Ferdinand; Simões-Costa, Marcos; Schechtman, Deborah; Pereira, Alexandre C; Brunet, Frédéric; Sweeney, Sarah; Pani, Ariel; Aronowicz, Jochanan; Lowe, Christopher J; Davidson, Bradley; Laudet, Vincent; Bronner, Marianne; de Oliveira, Paulo S L; Schubert, Michael; Xavier-Neto, José

    2011-01-01

    Aldehyde dehydrogenases (ALDHs) catabolize toxic aldehydes and process the vitamin A-derived retinaldehyde into retinoic acid (RA), a small diffusible molecule and a pivotal chordate morphogen. In this study, we combine phylogenetic, structural, genomic, and developmental gene expression analyses to examine the evolutionary origins of ALDH substrate preference. Structural modeling reveals that processing of small aldehydes, such as acetaldehyde, by ALDH2, versus large aldehydes, including retinaldehyde, by ALDH1A is associated with small versus large substrate entry channels (SECs), respectively. Moreover, we show that metazoan ALDH1s and ALDH2s are members of a single ALDH1/2 clade and that during evolution, eukaryote ALDH1/2s often switched between large and small SECs after gene duplication, transforming constricted channels into wide opened ones and vice versa. Ancestral sequence reconstructions suggest that during the evolutionary emergence of RA signaling, the ancestral, narrow-channeled metazoan ALDH1/2 gave rise to large ALDH1 channels capable of accommodating bulky aldehydes, such as retinaldehyde, supporting the view that retinoid-dependent signaling arose from ancestral cellular detoxification mechanisms. Our analyses also indicate that, on a more restricted evolutionary scale, ALDH1 duplicates from invertebrate chordates (amphioxus and ascidian tunicates) underwent switches to smaller and narrower SECs. When combined with alterations in gene expression, these switches led to neofunctionalization from ALDH1-like roles in embryonic patterning to systemic, ALDH2-like roles, suggesting functional shifts from signaling to detoxification. PMID:21169504

  1. Structural shifts of aldehyde dehydrogenase enzymes were instrumental for the early evolution of retinoid-dependent axial patterning in metazoans

    PubMed Central

    Sobreira, Tiago J. P.; Marlétaz, Ferdinand; Simões-Costa, Marcos; Schechtman, Deborah; Pereira, Alexandre C.; Brunet, Frédéric; Sweeney, Sarah; Pani, Ariel; Aronowicz, Jochanan; Lowe, Christopher J.; Davidson, Bradley; Laudet, Vincent; Bronner, Marianne; de Oliveira, Paulo S. L.; Schubert, Michael; Xavier-Neto, José

    2011-01-01

    Aldehyde dehydrogenases (ALDHs) catabolize toxic aldehydes and process the vitamin A-derived retinaldehyde into retinoic acid (RA), a small diffusible molecule and a pivotal chordate morphogen. In this study, we combine phylogenetic, structural, genomic, and developmental gene expression analyses to examine the evolutionary origins of ALDH substrate preference. Structural modeling reveals that processing of small aldehydes, such as acetaldehyde, by ALDH2, versus large aldehydes, including retinaldehyde, by ALDH1A is associated with small versus large substrate entry channels (SECs), respectively. Moreover, we show that metazoan ALDH1s and ALDH2s are members of a single ALDH1/2 clade and that during evolution, eukaryote ALDH1/2s often switched between large and small SECs after gene duplication, transforming constricted channels into wide opened ones and vice versa. Ancestral sequence reconstructions suggest that during the evolutionary emergence of RA signaling, the ancestral, narrow-channeled metazoan ALDH1/2 gave rise to large ALDH1 channels capable of accommodating bulky aldehydes, such as retinaldehyde, supporting the view that retinoid-dependent signaling arose from ancestral cellular detoxification mechanisms. Our analyses also indicate that, on a more restricted evolutionary scale, ALDH1 duplicates from invertebrate chordates (amphioxus and ascidian tunicates) underwent switches to smaller and narrower SECs. When combined with alterations in gene expression, these switches led to neofunctionalization from ALDH1-like roles in embryonic patterning to systemic, ALDH2-like roles, suggesting functional shifts from signaling to detoxification. PMID:21169504

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

    PubMed Central

    Petrosino, Jennifer M.; DiSilvestro, David; Ziouzenkova, Ouliana

    2014-01-01

    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. PMID:24594504

  3. Role of disulfiram in the in vitro inhibition of rat liver mitochondrial aldehyde dehydrogenase.

    PubMed

    Shen, M L; Lipsky, J J; Naylor, S

    2000-10-01

    The alcohol aversion therapy drug disulfiram has been shown to inhibit hepatic aldehyde dehydrogenase (ALDH), one of the key enzymes involved in ethanol metabolism. It is believed by some that disulfiram could be one of the active inhibitors in vivo. However, the actual interaction between disulfiram and ALDH remains ambiguous. We report here that when disulfiram inhibited recombinant rat liver mitochondrial ALDH (rlmALDH) in vitro, no significant molecular mass increase was detected during the first 30 min as determined by on-line HPLC-electrospray ionization mass spectrometry (LC-MS). This indicated that the inhibition in vitro was not caused directly by covalent adduct formation on the enzyme. We subsequently subjected both control and disulfiram-inhibited rlmALDH to Glu-C proteolytic digestion. LC-MS analysis of the Glu-C digestion of disulfiram-inhibited enzyme revealed that one peptide of M(r) = 4821, which contained the putative active site of the enzyme, exhibited a mass decrease of 2 amu as compared with the same peptide found in the Glu-C digestion of the control (M(r) = 4823). We believe that the loss of 2 amu indicated that inhibition of rlmALDH in vitro was due to formation of an intramolecular disulfide bond between two of the three adjacent cysteines in the active site, possibly via a very rapid and unstable mixed disulfide interchange reaction. Further confirmation of the intramolecular disulfide bond formation came from the fact that by adding dithiothreitol (DTT) we were able to recover partial enzyme activity. In addition, the peptide of M(r) = 4821 observed in the Glu-C digestion of the disulfiram-treated ALDH reverted to M(r) = 4823 after treatment with DTT, which indicated that the disulfide bond was reduced. We, thereby, conclude that disulfiram inhibited rlmALDH by forming an intramolecular disulfide, possibly via a fast intermolecular disulfiram interchange reaction. PMID:10974203

  4. Aldehyde dehydrogenase-independent bioactivation of nitroglycerin in porcine and bovine blood vessels.

    PubMed

    Neubauer, Regina; Wölkart, Gerald; Opelt, Marissa; Schwarzenegger, Christine; Hofinger, Marielies; Neubauer, Andrea; Kollau, Alexander; Schmidt, Kurt; Schrammel, Astrid; Mayer, Bernd

    2015-02-15

    The vascular bioactivation of the antianginal drug nitroglycerin (GTN), yielding 1,2-glycerol dinitrate and nitric oxide or a related activator of soluble guanylate cyclase, is catalyzed by aldehyde dehydrogenase-2 (ALDH2) in rodent and human blood vessels. The essential role of ALDH2 has been confirmed in many studies and is considered as general principle of GTN-induced vasodilation in mammals. However, this view is challenged by an early report showing that diphenyleneiodonium, which we recently characterized as potent ALDH2 inhibitor, has no effect on GTN-induced relaxation of bovine coronary arteries (De La Lande et al., 1996). We investigated this issue and found that inhibition of ALDH2 attenuates GTN-induced coronary vasodilation in isolated perfused rat hearts but has no effect on relaxation to GTN of bovine and porcine coronary arteries. This observation is explained by low levels of ALDH2 protein expression in bovine coronary arteries and several types of porcine blood vessels. ALDH2 mRNA expression and the rates of GTN denitration were similarly low, excluding a significant contribution of ALDH2 to the bioactivation of GTN in these vessels. Attempts to identify the responsible pathway with enzyme inhibitors did not provide conclusive evidence for the involvement of ALDH3A1, cytochrome P450, or GSH-S-transferase. Thus, the present manuscript describes a hitherto unrecognized pathway of GTN bioactivation in bovine and porcine blood vessels. If present in the human vasculature, this pathway might contribute to the therapeutic effects of organic nitrates that are not metabolized by ALDH2. PMID:25576686

  5. Aldehyde dehydrogenase-independent bioactivation of nitroglycerin in porcine and bovine blood vessels

    PubMed Central

    Neubauer, Regina; Wölkart, Gerald; Opelt, Marissa; Schwarzenegger, Christine; Hofinger, Marielies; Neubauer, Andrea; Kollau, Alexander; Schmidt, Kurt; Schrammel, Astrid; Mayer, Bernd

    2015-01-01

    The vascular bioactivation of the antianginal drug nitroglycerin (GTN), yielding 1,2-glycerol dinitrate and nitric oxide or a related activator of soluble guanylate cyclase, is catalyzed by aldehyde dehydrogenase-2 (ALDH2) in rodent and human blood vessels. The essential role of ALDH2 has been confirmed in many studies and is considered as general principle of GTN-induced vasodilation in mammals. However, this view is challenged by an early report showing that diphenyleneiodonium, which we recently characterized as potent ALDH2 inhibitor, has no effect on GTN-induced relaxation of bovine coronary arteries (De La Lande et al., 1996). We investigated this issue and found that inhibition of ALDH2 attenuates GTN-induced coronary vasodilation in isolated perfused rat hearts but has no effect on relaxation to GTN of bovine and porcine coronary arteries. This observation is explained by low levels of ALDH2 protein expression in bovine coronary arteries and several types of porcine blood vessels. ALDH2 mRNA expression and the rates of GTN denitration were similarly low, excluding a significant contribution of ALDH2 to the bioactivation of GTN in these vessels. Attempts to identify the responsible pathway with enzyme inhibitors did not provide conclusive evidence for the involvement of ALDH3A1, cytochrome P450, or GSH-S-transferase. Thus, the present manuscript describes a hitherto unrecognized pathway of GTN bioactivation in bovine and porcine blood vessels. If present in the human vasculature, this pathway might contribute to the therapeutic effects of organic nitrates that are not metabolized by ALDH2. PMID:25576686

  6. Aldehyde dehydrogenases inhibition eradicates leukemia stem cells while sparing normal progenitors.

    PubMed

    Venton, G; Pérez-Alea, M; Baier, C; Fournet, G; Quash, G; Labiad, Y; Martin, G; Sanderson, F; Poullin, P; Suchon, P; Farnault, L; Nguyen, C; Brunet, C; Ceylan, I; Costello, R T

    2016-01-01

    The vast majority of patients with acute myeloid leukemia (AML) achieve complete remission (CR) after standard induction chemotherapy. However, the majority subsequently relapse and die of the disease. A leukemia stem cell (LSC) paradigm has been invoked to explain this failure of CR to reliably translate into cure. Indeed, LSCs are highly enriched in CD34+CD38- leukemic cells that exhibit positive aldehyde dehydrogenase activity (ALDH+) on flow cytometry, these LSCs are resistant to currently existing treatments in AML such as cytarabine and anthracycline that, at the cost of great toxicity on normal cells, are highly active against the leukemic bulk, but spare the LSCs responsible for relapse. To try to combat the LSC population selectively, a well-characterized ALDH inhibitor by the trivial name of dimethyl ampal thiolester (DIMATE) was assessed on sorted CD34+CD38- subpopulations from AML patients and healthy patients. ALDH activity and cell viability were monitored by flow cytometry. From enzyme kinetic studies DIMATE is an active enzyme-dependent, competitive, irreversible inhibitor of ALDH1. On cells in culture, DIMATE is a powerful inhibitor of ALDHs 1 and 3, has a major cytotoxic activity on human AML cell lines. Moreover, DIMATE is highly active against leukemic populations enriched in LSCs, but, unlike conventional chemotherapy, DIMATE is not toxic for healthy hematopoietic stem cells which retained, after treatment, their self-renewing and multi-lineage differentiation capacity in immunodeficient mice, xenografted with human leukemic cells. DIMATE eradicates specifically human AML cells and spares healthy mouse hematologic cells. PMID:27611922

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

    PubMed

    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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

  11. Mitigation of Radiation-Induced Dermatitis by Activation of Aldehyde Dehydrogenase 2 Using Topical Alda-1 in Mice1

    PubMed Central

    Ning, Shoucheng; Budas, Grant R.; Churchill, Eric N.; Chen, Che-Hong; Knox, Susan J.; Mochly-Rosen, Daria

    2012-01-01

    Ning, S., Budas, G. R., Churchill, E. N., Chen, C., Knox, S. J. and Mochly-Rosen, D. Mitigation of Radiation-Induced Dermatitis by Activation of Aldehyde Dehydrogenase 2 Using Topical Alda-1 in Mice. Radiation-induced dermatitis is a debilitating clinical problem in cancer patients undergoing cancer radiation therapy. It is also a possible outcome of exposure to high levels of radiation due to accident or hostile activity. We report that activation of aldehyde dehydrogenase 2 (ALDH2) enzymatic activity using the allosteric agonist, Alda-1, significantly reduced 4-hydroxynonenal adducts accumulation, delayed the onset of radiation dermatitis and substantially reduced symptoms in a clinically-relevant model of radiation-induced dermatitis. Importantly, Alda-1 did not radioprotect tumors in mice. Rather, it increased the sensitivity of the tumors to radiation therapy. This is the first report of reactive aldehydes playing a role in the intrinsic radiosensitivity of normal and tumor tissues. Our findings suggest that ALDH2 represents a novel target for the treatment of radiation dermatitis without reducing the benefit of radiotherapy. PMID:22404739

  12. Aldehyde dehydrogenase 3A1 promotes multi-modality resistance and alters gene expression profile in human breast adenocarcinoma MCF-7 cells.

    PubMed

    Voulgaridou, Georgia-Persephoni; Kiziridou, Magdalini; Mantso, Theodora; Chlichlia, Katerina; Galanis, Alex; Koukourakis, Michael I; Franco, Rodrigo; Panayiotidis, Mihalis I; Pappa, Aglaia

    2016-08-01

    Aldehyde dehydrogenases participate in a variety of cellular homeostatic mechanisms like metabolism, proliferation, differentiation, apoptosis, whereas recently, they have been implicated in normal and cancer cell stemness. We explored roles for ALDH3A1 in conferring resistance to chemotherapeutics/radiation/oxidative stress and whether ectopic overexpression of ALDH3A1 could lead to alterations of gene expression profile associated with cancer stem cell-like phenotype. MCF-7 cells were stably transfected either with an empty vector (mock) or human aldehyde dehydrogenase 3A1 cDNA. The expression of aldehyde dehydrogenase 3A1 in MCF-7 cells was associated with altered cell proliferation rate and enhanced cell resistance against various chemotherapeutic drugs (4-hydroxyperoxycyclophosphamide, doxorubicin, etoposide, and 5-fluorouracil). Aldehyde dehydrogenase 3A1 expression also led to increased tolerance of MCF-7 cells to gamma radiation and hydrogen peroxide-induced stress. Furthermore, aldehyde dehydrogenase 3A1-expressing MCF-7 cells exhibited gene up-regulation of cyclins A, B1, B2, and down-regulation of cyclin D1 as well as transcription factors p21, CXR4, Notch1, SOX2, SOX4, OCT4, and JAG1. When compared to mock cells, no changes were observed in mRNA levels of ABCA2 and ABCB1 protein pumps with only a minor decrease of the ABCG2 pump in the aldehyde dehydrogenase 3A1-expressing cells. Also, the adhesion molecules EpCAM and CD49F were also found to be up-regulated in aldehyde dehydrogenase 3A1expressing cells. Taken together, ALDH3A1 confers a multi-modality resistance phenotype in MCF-7 cells associated with slower growth rate, increased clonogenic capacity, and altered gene expression profile, underlining its significance in cell homeostasis. PMID:27276244

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

    PubMed Central

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

    2015-01-01

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

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

    SciTech Connect

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

    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

  15. Substrate specificity, substrate channeling, and allostery in BphJ: an acylating aldehyde dehydrogenase associated with the pyruvate aldolase BphI.

    PubMed

    Baker, Perrin; Carere, Jason; Seah, Stephen Y K

    2012-06-01

    BphJ, a nonphosphorylating acylating aldehyde dehydrogenase, catalyzes the conversion of aldehydes to form acyl-coenzyme A in the presence of NAD(+) and coenzyme A (CoA). The enzyme is structurally related to the nonacylating aldehyde dehydrogenases, aspartate-β-semialdehyde dehydrogenase and phosphorylating glyceraldehyde-3-phosphate dehydrogenase. Cys-131 was identified as the catalytic thiol in BphJ, and pH profiles together with site-specific mutagenesis data demonstrated that the catalytic thiol is not activated by an aspartate residue, as previously proposed. In contrast to the wild-type enzyme that had similar specificities for two- or three-carbon aldehydes, an I195A variant was observed to have a 20-fold higher catalytic efficiency for butyraldehyde and pentaldehyde compared to the catalytic efficiency of the wild type toward its natural substrate, acetaldehyde. BphJ forms a heterotetrameric complex with the class II aldolase BphI that channels aldehydes produced in the aldol cleavage reaction to the dehydrogenase via a molecular tunnel. Replacement of Ile-171 and Ile-195 with bulkier amino acid residues resulted in no more than a 35% reduction in acetaldehyde channeling efficiency, showing that these residues are not critical in gating the exit of the channel. Likewise, the replacement of Asn-170 in BphJ with alanine and aspartate did not substantially alter aldehyde channeling efficiencies. Levels of activation of BphI by BphJ N170A, N170D, and I171A were reduced by ≥3-fold in the presence of NADH and ≥4.5-fold when BphJ was undergoing turnover, indicating that allosteric activation of the aldolase has been compromised in these variants. The results demonstrate that the dehydrogenase coordinates the catalytic activity of BphI through allostery rather than through aldehyde channeling. PMID:22574886

  16. Alcohol dehydrogenases from Scheffersomyces stipitis involved in the detoxification of aldehyde inhibitors derived from lignocellulosic biomass conversion.

    PubMed

    Ma, Menggen; Wang, Xu; Zhang, Xiaoping; Zhao, Xianxian

    2013-09-01

    Aldehyde inhibitors such as furfural and 5-hydroxymethylfurfural (HMF) are generated from biomass pretreatment. Scheffersomyces stipitis is able to reduce furfural and HMF to less toxic furanmethanol and furan-2,5-dimethanol; however, the enzymes involved in the reductive reaction still remain unknown. In this study, transcription responses of two known and five putative alcohol dehydrogenase genes from S. stipitis were analyzed under furfural and HMF stress conditions. All the seven alcohol dehydrogenase genes were also cloned and overexpressed for their activity analyses. Our results indicate that transcriptions of SsADH4 and SsADH6 were highly induced under furfural and HMF stress conditions, and the proteins encoded by them exhibited NADH- and/or NADPH-dependent activities for furfural and HMF reduction, respectively. For furfural reduction, NADH-dependent activity was also observed in SsAdh1p and NAD(P)H-dependent activities were also observed in SsAdh5p and SsAdh7p. For HMF reduction, NADPH-dependent activities were also observed in SsAdh5p and SsAdh7p. SsAdh4p displayed the highest NADPH-dependent specific activity and catalytic efficiency for reduction of both furfural and HMF among the seven alcohol dehydrogenases. Enzyme activities of all SsADH proteins were more stable under acidic condition. For most SsADH proteins, the optimum temperature for enzyme activities was 30 °C and more than 50 % enzyme activities remained at 60 °C. Reduction activities of formaldehyde, acetaldehyde, isovaleraldehyde, benzaldehyde, and phenylacetaldehyde were also observed in some SsADH proteins. Our results indicate that multiple alcohol dehydrogenases in S. stipitis are involved in the detoxification of aldehyde inhibitors derived from lignocellulosic biomass conversion. PMID:23912116

  17. Molecular cloning of a plant betaine-aldehyde dehydrogenase, an enzyme implicated in adaptation to salinity and drought.

    PubMed

    Weretilnyk, E A; Hanson, A D

    1990-04-01

    Many plants, as well as other organisms, accumulate betaine (N,N,N-trimethylglycine) as a nontoxic or protective osmolyte under saline or dry conditions. In plants, the last step in betaine synthesis is catalyzed by betaine-aldehyde dehydrogenase (BADH, EC 1.2.1.8), a nuclear-encoded chloroplastic enzyme. A cDNA clone for BADH (1812 base pairs) was selected from a lambda gt10 cDNA library derived from leaves of salt-stressed spinach (Spinacia oleracea L.). The library was screened with oligonucleotide probes corresponding to amino acid sequences of two peptides prepared from purified BADH. The authenticity of the clone was confirmed by nucleotide sequence analysis; this analysis demonstrated the presence of a 1491-base-pair open reading frame that contained sequences encoding 12 peptide fragments of BADH. The clone hybridized to a 1.9-kilobase mRNA from spinach leaves; this mRNA was more abundant in salt-stressed plants, consistent with the known salt induction of BADH activity. The amino acid sequence deduced from the BADH cDNA sequence showed substantial similarities to those for nonspecific aldehyde dehydrogenases (EC 1.2.1.3 and EC 1.2.1.5) from several sources, including absolute conservation of a decapeptide in the probable active site. Comparison of deduced and determined amino acid sequences indicated that the transit peptide may comprise only 7 or 8 residues, which is atypically short for precursors to stromal proteins. PMID:2320587

  18. Ectopic overexpression of the aldehyde dehydrogenase ALDH21 from Syntrichia caninervis in tobacco confers salt and drought stress tolerance.

    PubMed

    Yang, Honglan; Zhang, Daoyuan; Li, Haiyan; Dong, Lingfeng; Lan, Haiyan

    2015-10-01

    Aldehyde dehydrogenases are important enzymes that play vital roles in mitigating oxidative/electrophilic stress when plants are exposed to environmental stress. An aldehyde dehydrogenase gene from Syntrichia caninervis, ScALDH21, was introduced into tobacco using Agrobacterium-mediated transformation to generate ScALDH21-overexpressing tobacco plants to investigate its effect on drought and salt resistance. Detached leaves from ScALDH21-overexpressing tobacco plants showed less water loss than those from nontransgenic plants. When subjected to drought and salt stress, transgenic plants displayed higher germination ratios, higher root lengths, greater fresh weight, higher proline accumulation, lower malondialdehyde (MDA) contents and stronger photosynthetic capacities, as well as higher activities of antioxidant enzymes, i.e., superoxide dismutase, catalase and peroxidase, compared with control plants. Therefore, ScALDH21 overexpression in transgenic tobacco plants can enhance drought and salt tolerance and can be used as a candidate gene for the molecular breeding of salt- and drought-tolerant plants. PMID:26202169

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

    PubMed Central

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

    2016-01-01

    Ethanol and butanol biosynthesis in Clostridium acetobutylicum share common aldehyde/alcohol dehydrogenases. However, little is known about the relative contributions of these multiple dehydrogenases to ethanol and butanol production respectively. The contributions of six aldehyde/alcohol dehydrogenases of C. acetobutylicum on butanol and ethanol production were evaluated through inactivation of the corresponding genes respectively. For butanol production, the relative contributions from these enzymes were: AdhE1 > BdhB > BdhA ≈ YqhD > SMB_P058 > AdhE2. For ethanol production, the contributions were: AdhE1 > BdhB > YqhD > SMB_P058 > AdhE2 > BdhA. AdhE1 and BdhB are two essential enzymes for butanol and ethanol production. AdhE1 was relatively specific for butanol production over ethanol, while BdhB, YqhD, and SMB_P058 favor ethanol production over butanol. Butanol synthesis was increased in the adhE2 mutant, which had a higher butanol/ethanol ratio (8.15:1) compared with wild type strain (6.65:1). Both the SMB_P058 mutant and yqhD mutant produced less ethanol without loss of butanol formation, which led to higher butanol/ethanol ratio, 10.12:1 and 10.17:1, respectively. To engineer a more efficient butanol-producing strain, adhE1 could be overexpressed, furthermore, adhE2, SMB_P058, yqhD are promising gene inactivation targets. This work provides useful information guiding future strain improvement for butanol production. PMID:27321949

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

    PubMed

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

    2016-01-01

    Ethanol and butanol biosynthesis in Clostridium acetobutylicum share common aldehyde/alcohol dehydrogenases. However, little is known about the relative contributions of these multiple dehydrogenases to ethanol and butanol production respectively. The contributions of six aldehyde/alcohol dehydrogenases of C. acetobutylicum on butanol and ethanol production were evaluated through inactivation of the corresponding genes respectively. For butanol production, the relative contributions from these enzymes were: AdhE1 > BdhB > BdhA ≈ YqhD > SMB_P058 > AdhE2. For ethanol production, the contributions were: AdhE1 > BdhB > YqhD > SMB_P058 > AdhE2 > BdhA. AdhE1 and BdhB are two essential enzymes for butanol and ethanol production. AdhE1 was relatively specific for butanol production over ethanol, while BdhB, YqhD, and SMB_P058 favor ethanol production over butanol. Butanol synthesis was increased in the adhE2 mutant, which had a higher butanol/ethanol ratio (8.15:1) compared with wild type strain (6.65:1). Both the SMB_P058 mutant and yqhD mutant produced less ethanol without loss of butanol formation, which led to higher butanol/ethanol ratio, 10.12:1 and 10.17:1, respectively. To engineer a more efficient butanol-producing strain, adhE1 could be overexpressed, furthermore, adhE2, SMB_P058, yqhD are promising gene inactivation targets. This work provides useful information guiding future strain improvement for butanol production. PMID:27321949

  1. Enhanced aldehyde dehydrogenase activity by regenerating NAD+ in Klebsiella pneumoniae and implications for the glycerol dissimilation pathways.

    PubMed

    Li, Ying; Su, Mingyue; Ge, Xizhen; Tian, Pingfang

    2013-10-01

    In Klebsiella pneumoniae, 3-hydroxypropaldehyde is converted to 3-hydroxypropionic acid (3-HP) by aldehyde dehydrogenase (ALDH) with NAD(+) as a cofactor. Although ALDH overexpression stimulates the formation of 3-HP, it ceases to accumulate when NAD(+) is exhausted. Here we show that NAD(+) regeneration, together with ALDH overexpression, facilitates 3-HP production and benefits cell growth. Three distinct NAD(+)-regenerating enzymes: NADH oxidase and NADH dehydrogenase from K. pneumoniae, and glycerol-3-phosphate dehydrogenase (GPD1) from Saccharomyces cerevisiae, were individually expressed in K. pneumoniae. In vitro assay showed their higher activities than that of the control, indicating their capacities to regenerate NAD(+). When they were respectively co-expressed with ALD4, an ALDH from S. cerevisiae, the activities of ALD4 were significantly elevated compared with that expressing ALD4 alone, suggesting that the regenerated NAD(+) enhanced the activity of ALD4. More interestingly, the growth rates of all NAD(+)-regenerating strains were prolonged in comparison with the control, indicating that NAD(+) regeneration stimulated cell proliferation. This study not only reveals the reliance of ALD4 activity on NAD(+) availability but also provides a method for regulating the dha regulon. PMID:23794046

  2. POSTNATAL EFFECTS OF HEXACHLOROBENZENE (HCB) ON CARDIAC LACTIC DEHYDROGENASE (LDH) AND CREATINE KINASE (CK) ISOZYMES IN CD-1 MICE

    EPA Science Inventory

    Pregnant CD-1 mice were treated with hexachlorobenzene (HCB) by gavage at doses of 0, 1, 10 and 50 mg HCB/kg body weight on days 6-17 of gestation and studied on day 1 or 21 postpartum (pp). Hearts of the dams and pups were assayed for lactic dehydrogenase (LDH) and creatine kina...

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

    PubMed Central

    2009-01-01

    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. PMID:19164088

  4. Human aldehyde dehydrogenase 3A1 (ALDH3A1): biochemical characterization and immunohistochemical localization in the cornea.

    PubMed Central

    Pappa, Aglaia; Estey, Tia; Manzer, Rizwan; Brown, Donald; Vasiliou, Vasilis

    2003-01-01

    ALDH3A1 (aldehyde dehydrogenase 3A1) is expressed at high concentrations in the mammalian cornea and it is believed that it protects this vital tissue and the rest of the eye against UV-light-induced damage. The precise biological function(s) and cellular distribution of ALDH3A1 in the corneal tissue remain to be elucidated. Among the hypotheses proposed for ALDH3A1 function in cornea is detoxification of aldehydes formed during UV-induced lipid peroxidation. To investigate in detail the biochemical properties and distribution of this protein in the human cornea, we expressed human ALDH3A1 in Sf9 insect cells using a baculovirus vector and raised monoclonal antibodies against ALDH3A1. Recombinant ALDH3A1 protein was purified to homogeneity with a single-step affinity chromatography method using 5'-AMP-Sepharose 4B. Human ALDH3A1 demonstrated high substrate specificity for medium-chain (6 carbons and more) saturated and unsaturated aldehydes, including 4-hydroxy-2-nonenal, which are generated by the peroxidation of cellular lipids. Short-chain aliphatic aldehydes, such as acetaldehyde, propionaldehyde and malondialdehyde, were found to be very poor substrates for human ALDH3A1. In addition, ALDH3A1 metabolized glyceraldehyde poorly and did not metabolize glucose 6-phosphate, 6-phosphoglucono-delta-lactone and 6-phosphogluconate at all, suggesting that this enzyme is not involved in either glycolysis or the pentose phosphate pathway. Immunohistochemistry in human corneas, using the monoclonal antibodies described herein, revealed ALDH3A1 expression in epithelial cells and stromal keratocytes, but not in endothelial cells. Overall, these cumulative findings support the metabolic function of ALDH3A1 as a part of a corneal cellular defence mechanism against oxidative damage caused by aldehydic products of lipid peroxidation. Both recombinant human ALDH3A1 and the highly specific monoclonal antibodies described in the present paper may prove to be useful in probing

  5. Androgen regulation of aldehyde dehydrogenase 1A3 (ALDH1A3) in androgen responsive human prostate cancer cell LNCaP.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous gene array data from our laboratory identified the retinoic acid (RA) biosynthesis enzyme aldehyde dehydrogenase 1A3 (ALDH1A3) as a putative androgen-responsive gene in prostate cancer epithelial cells (LNCaP). In the present study we attempted to identify if any of the three ALDH1A/RA synt...

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

    PubMed Central

    Zhao, Yan; Wang, Chuancai

    2015-01-01

    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. PMID:26491656

  7. The longitudinal effect of the aldehyde dehydrogenase 2*2 allele on the risk for nonalcoholic fatty liver disease.

    PubMed

    Oniki, K; Morita, K; Watanabe, T; Kajiwara, A; Otake, K; Nakagawa, K; Sasaki, Y; Ogata, Y; Saruwatari, J

    2016-01-01

    Aldehyde dehydrogenase 2 (ALDH2) detoxifies toxic aldehydes and has a key role in protecting the liver. An elevated gamma-glutamyl transferase (GGT) level is related to oxidative stress and nonalcoholic fatty liver disease (NAFLD). We herein investigated the association between inactive ALDH2*2 allele (rs671) and the risk of NAFLD, including the relationship to the GGT level. A retrospective follow-up study (mean 5.4±1.1 years) was conducted among 341 Japanese health screening program participants. The receiver operating characteristic curve indicated that the GGT level predicted the development of NAFLD (area under the curve: 0.65, P<0.05) with a cutoff value of 25.5 IUl(-1). The longitudinal risk of NAFLD was higher in the ALDH2*2 allele carriers than in the noncarriers (odds ratio (OR): 2.30, 95% confidence interval (CI): 1.21-4.40), and the risk was further increased among the *2 allele carriers with GGT values ⩾25.5 IUl(-1) (OR: 4.28, 95% CI: 1.80-10.19). On the other hand, there were no significant changes in the subjects' body weight and body mass index during observation period. The ALDH2*2 allele, in relation to the GGT level, may potentially be a novel risk factor for NAFLD. PMID:27214654

  8. The longitudinal effect of the aldehyde dehydrogenase 2*2 allele on the risk for nonalcoholic fatty liver disease

    PubMed Central

    Oniki, K; Morita, K; Watanabe, T; Kajiwara, A; Otake, K; Nakagawa, K; Sasaki, Y; Ogata, Y; Saruwatari, J

    2016-01-01

    Aldehyde dehydrogenase 2 (ALDH2) detoxifies toxic aldehydes and has a key role in protecting the liver. An elevated gamma-glutamyl transferase (GGT) level is related to oxidative stress and nonalcoholic fatty liver disease (NAFLD). We herein investigated the association between inactive ALDH2*2 allele (rs671) and the risk of NAFLD, including the relationship to the GGT level. A retrospective follow-up study (mean 5.4±1.1 years) was conducted among 341 Japanese health screening program participants. The receiver operating characteristic curve indicated that the GGT level predicted the development of NAFLD (area under the curve: 0.65, P<0.05) with a cutoff value of 25.5 IUl−1. The longitudinal risk of NAFLD was higher in the ALDH2*2 allele carriers than in the noncarriers (odds ratio (OR): 2.30, 95% confidence interval (CI): 1.21–4.40), and the risk was further increased among the *2 allele carriers with GGT values ⩾25.5 IUl−1 (OR: 4.28, 95% CI: 1.80–10.19). On the other hand, there were no significant changes in the subjects' body weight and body mass index during observation period. The ALDH2*2 allele, in relation to the GGT level, may potentially be a novel risk factor for NAFLD. PMID:27214654

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

    PubMed

    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. PMID:3593337

  10. Sjögren-Larsson syndrome. Deficient activity of the fatty aldehyde dehydrogenase component of fatty alcohol:NAD+ oxidoreductase in cultured fibroblasts.

    PubMed Central

    Rizzo, W B; Craft, D A

    1991-01-01

    Sjögren-Larsson syndrome (SLS) is an inherited disorder associated with impaired fatty alcohol oxidation due to deficient activity of fatty alcohol:NAD+ oxidoreductase (FAO). FAO is a complex enzyme which consists of two separate proteins that sequentially catalyze the oxidation of fatty alcohol to fatty aldehyde and fatty acid. To determine which enzymatic component of FAO was deficient in SLS, we assayed fatty aldehyde dehydrogenase (FALDH) and fatty alcohol dehydrogenase in cultured fibroblasts from seven unrelated SLS patients. All SLS cells were selectively deficient in the FALDH component of FAO, and had normal activity of fatty alcohol dehydrogenase. The extent of FALDH deficiency in SLS cells depended on the aliphatic aldehyde used as substrate, ranging from 62% of mean normal activity using propionaldehyde as substrate to 8% of mean normal activity with octadecanal. FALDH activity in obligate SLS heterozygotes was partially decreased to 49 +/- 7% of mean normal activity using octadecanal as substrate. Differential centrifugation studies in fibroblasts indicated that this FALDH enzyme was largely particulate; soluble FALDH activity was normal in SLS cells. Intact SLS fibroblasts oxidized octadecanol to fatty acid at less than 10% of the normal rate, but oxidized free octadecanal normally, suggesting that the FALDH affected in SLS is chiefly involved in the oxidation of fatty alcohol to fatty acid. These results show that the primary enzymatic defect in SLS is the FALDH component of the FAO complex, which leads to deficient oxidation of fatty aldehyde derived from fatty alcohol. PMID:1939650

  11. Isozyme multiplicity with anomalous dimer patterns in a class III alcohol dehydrogenase. Effects on the activity and quaternary structure of residue exchanges at "nonfunctional" sites in a native protein.

    PubMed

    Danielsson, O; Shafqat, J; Estonius, M; el-Ahmad, M; Jörnvall, H

    1996-11-19

    The isozymes of class III alcohol dehydrogenase/glutathione-dependent formaldehyde dehydrogenase from cod were characterized. They exhibited three unexpected properties of general interest. First, these dimeric isozymes, derived from two types of subunit (h and l, for high- and low-activity forms), were recovered from liver preparations in only the homodimeric ll and heterodimeric hl combinations. Dissociation and reassociation of the isolated hl form in vitro also resulted in lower yields of the hh than the ll homodimer, although class III subunits are usually freely associable over wide borders of divergence (human and Drosophila). The h and l primary structures show that both chain types are characteristic of class III enzymes, without large amino acid replacements at positions of known subunit interactions. Hence, the hh dimer partial restriction indicates nontraditional alterations at h-subunit interfaces. The structure provides a possible explanation, in the form of h-chain modifications that may influence the anchoring of a loop at positions of two potentially deamidative beta-aspartyl shifts at distant Asn-Gly structures. Second the ll and hl forms differ in enzymatic properties, having 5-fold different K(m) values for NAD+ at pH 8, different K(m) values for S-(hydroxymethyl)glutathione (10 versus 150 microM), and different specific activities (4.5 versus 41 units/mg), with ll resembling and hl deviating from human and other class III alcohol dehydrogenases. However, functional residues lining substrate and coenzyme pockets in the known conformations of homologous forms are largely identical in the two isozymes [only minor conservative exchanges of Val/Leu116, Val/Leu203, Ile/Val224, and Ile/Val269 (numbering system of the human class I enzyme)], again indicating effects from distantly positioned h-chain replacements. Third, the two isozymes differ a surprising amount in amino acid sequence (18%, the same as the piscine/ human difference), reflecting a

  12. Aldehyde dehydrogenase 2 (ALDH2) and alcohol dehydrogenase 1B (ADH1B) polymorphisms exacerbate bladder cancer risk associated with alcohol drinking: gene-environment interaction.

    PubMed

    Masaoka, Hiroyuki; Ito, Hidemi; Soga, Norihito; Hosono, Satoyo; Oze, Isao; Watanabe, Miki; Tanaka, Hideo; Yokomizo, Akira; Hayashi, Norio; Eto, Masatoshi; Matsuo, Keitaro

    2016-06-01

    Although a range of chemical exposures (cigarette smoking and occupational exposure) are recognized risk factors for the development of bladder cancer (BCa), many epidemiological studies have demonstrated that alcohol drinking is not associated with BCa risk. Aldehyde dehydrogenase 2 (ALDH2; rs671, Glu504Lys) and alcohol dehydrogenase 1B (ADH1B; rs1229984, His47Arg) polymorphisms impact the accumulation of acetaldehyde, resulting in an increased risk of various cancers. To date, however, no studies evaluating the association between BCa risk and alcohol drinking have considered these polymorphisms. Here, we conducted a matched case-control study to investigate whether ALDH2 and ADH1B polymorphisms influence BCa risk associated with alcohol drinking. Cases were 74 BCa patients and controls were 740 first-visit outpatients without cancer at Aichi Cancer Center Hospital between January 2001 and December 2005. Odds ratio (OR), 95% confidence interval (CI) and gene-environment interaction were assessed by conditional logistic regression analysis with adjustment for potential confounders. Results showed that ALDH2 Glu/Lys was associated with a significantly increased risk of BCa compared with Glu/Glu (OR 2.03, 95% CI 1.14-3.62, P = 0.017). In contrast, ALDH2 Glu/Lys showed no increase in risk among the stratum of never drinkers compared with Glu/Glu, indicating a gene-environment interaction. ADH1B His/Arg had an OR of 1.98 (1.20-3.24, P = 0.007) compared with His/His. ADH1B Arg+ showed a similar OR and 95% CI. Individuals with ALDH2 Glu/Lys and ADH1B Arg+ had the highest risk of BCa compared with ALDH2 Glu/Glu and ADH1B His/His [OR 4.00 (1.81-8.87), P = 0.001]. PMID:26992901

  13. Simultaneous Involvement of a Tungsten-Containing Aldehyde:Ferredoxin Oxidoreductase and a Phenylacetaldehyde Dehydrogenase in Anaerobic Phenylalanine Metabolism

    PubMed Central

    Debnar-Daumler, Carlotta; Seubert, Andreas; Schmitt, Georg

    2014-01-01

    Anaerobic phenylalanine metabolism in the denitrifying betaproteobacterium Aromatoleum aromaticum is initiated by conversion of phenylalanine to phenylacetate, which is further metabolized via benzoyl-coenzyme A (CoA). The formation of phenylacetate is catalyzed by phenylalanine transaminase, phenylpyruvate decarboxylase, and a phenylacetaldehyde-oxidizing enzyme. The presence of these enzymes was detected in extracts of cells grown with phenylalanine and nitrate. We found that two distinct enzymes are involved in the oxidation of phenylacetaldehyde to phenylacetate, an aldehyde:ferredoxin oxidoreductase (AOR) and a phenylacetaldehyde dehydrogenase (PDH). Based on sequence comparison, growth studies with various tungstate concentrations, and metal analysis of the enriched enzyme, AOR was shown to be a tungsten-containing enzyme, necessitating specific cofactor biosynthetic pathways for molybdenum- and tungsten-dependent enzymes simultaneously. We predict from the genome sequence that most enzymes of molybdopterin biosynthesis are shared, while the molybdate/tungstate uptake systems are duplicated and specialized paralogs of the sulfur-inserting MoaD and the metal-inserting MoeA proteins seem to be involved in dedicating biosynthesis toward molybdenum or tungsten cofactors. We also characterized PDH biochemically and identified both NAD+ and NADP+ as electron acceptors. We identified the gene coding for the enzyme and purified a recombinant Strep-tagged PDH variant. The homotetrameric enzyme is highly specific for phenylacetaldehyde, has cooperative kinetics toward the substrate, and shows considerable substrate inhibition. Our data suggest that A. aromaticum utilizes PDH as the primary enzyme during anaerobic phenylalanine degradation, whereas AOR is not essential for the metabolic pathway. We hypothesize a function as a detoxifying enzyme if high aldehyde concentrations accumulate in the cytoplasm, which would lead to substrate inhibition of PDH. PMID:24214948

  14. Mitochondrial Aldehyde Dehydrogenase Activation by Alda‐1 Inhibits Atherosclerosis and Attenuates Hepatic Steatosis in Apolipoprotein E‐Knockout Mice

    PubMed Central

    Stachowicz, Aneta; Olszanecki, Rafał; Suski, Maciej; Wiśniewska, Anna; Totoń‐Żurańska, Justyna; Madej, Józef; Jawień, Jacek; Białas, Magdalena; Okoń, Krzysztof; Gajda, Mariusz; Głombik, Katarzyna; Basta‐Kaim, Agnieszka; Korbut, Ryszard

    2014-01-01

    Background Mitochondrial dysfunction has been shown to play an important role in the development of atherosclerosis and nonalcoholic fatty liver disease (NAFLD). Mitochondrial aldehyde dehydrogenase (ALDH2), an enzyme responsible for the detoxification of reactive aldehydes, is considered to exert protective function in mitochondria. We investigated the influence of Alda‐1, an activator of ALDH2, on atherogenesis and on the liver steatosis in apolipoprotein E knockout (apoE−/−) mice. Methods and Results Alda‐1 caused decrease of atherosclerotic lesions approximately 25% as estimated by “en face” and “cross‐section” methods without influence on plasma lipid profile, atherosclerosis‐related markers of inflammation, and macrophage and smooth muscle content in the plaques. Plaque nitrotyrosine was not changed upon Alda‐1 treatment, and there were no changes in aortic mRNA levels of factors involved in antioxidative defense, regulation of apoptosis, mitogenesis, and autophagy. Hematoxylin/eosin staining showed decrease of steatotic changes in liver of Alda‐1‐treated apoE−/− mice. Alda‐1 attenuated formation of 4‐hydroxy‐2‐nonenal (4‐HNE) protein adducts and decreased triglyceride content in liver tissue. Two‐dimensional electrophoresis coupled with mass spectrometry identified 20 differentially expressed mitochondrial proteins upon Alda‐1 treatment in liver of apoE−/− mice, mostly proteins related to metabolism and oxidative stress. The most up‐regulated were the proteins that participated in beta oxidation of fatty acids. Conclusions Collectively, Alda‐1 inhibited atherosclerosis and attenuated NAFLD in apoE−/− mice. The pattern of changes suggests a beneficial effect of Alda‐1 in NAFLD; however, the exact liver functional consequences of the revealed alterations as well as the mechanism(s) of antiatherosclerotic Alda‐1 action require further investigation. PMID:25392542

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

    SciTech Connect

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

    2013-11-27

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

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

    DOE PAGESBeta

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

    2013-11-27

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

  17. Folate, alcohol, and aldehyde dehydrogenase 2 polymorphism and the risk of oral and pharyngeal cancer in Japanese.

    PubMed

    Matsuo, Keitaro; Rossi, Marta; Negri, Eva; Oze, Isao; Hosono, Satoyo; Ito, Hidemi; Watanabe, Miki; Yatabe, Yasushi; Hasegawa, Yasuhisa; Tanaka, Hideo; Tajima, Kazuo; La Vecchia, Carlo

    2012-03-01

    Folate consumption is inversely associated with the risk of oral and pharyngeal cancer (OPC) and potentially interacts with alcohol drinking in the risk of OPC. Aldehyde dehydrogenase 2 (ALDH2) gene polymorphism is known to interact with alcohol consumption. The aim of this study was to investigate potential interaction between folate, alcohol drinking, and ALDH2 polymorphism in the risk of OPC in a Japanese population. The study group comprised 409 head and neck cancer cases and 1227 age-matched and sex-matched noncancer controls; of these, 251 cases and 759 controls were evaluated for ALDH rs671 polymorphism. Associations were assessed by odds ratios and 95% confidence intervals in multiple logistic regression models. We observed an inverse association between folate consumption and OPC risk. The odds ratio for high folate intake was 0.53 (95% confidence interval: 0.36-0.77) relative to low intake (P trend=0.003). This association was consistent across strata of sex, age, smoking, and ALDH2 genotypes. Interaction between folate consumption, drinking, and ALDH2 genotype was remarkable (three-way interaction, P<0.001). We observed significant interaction among folate, drinking, and ALDH2 genotype in the Japanese population. PMID:21946912

  18. Deficient Expression of Aldehyde Dehydrogenase 1A1 Is Consistent with Increased Sensitivity of Gorlin Syndrome Patients to Radiation Carcinogenesis

    SciTech Connect

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

    2015-06-01

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

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

    PubMed Central

    Opdenaker, Lynn M; Arnold, Kimberly M; Pohlig, Ryan T; Padmanabhan, Jayasree S; Flynn, Daniel C; Sims-Mourtada, Jennifer

    2014-01-01

    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. PMID:25540596

  20. E. coli metabolic protein aldehyde-alcohol dehydrogenase-E binds to the ribosome: a unique moonlighting action revealed.

    PubMed

    Shasmal, Manidip; Dey, Sandip; Shaikh, Tanvir R; Bhakta, Sayan; Sengupta, Jayati

    2016-01-01

    It is becoming increasingly evident that a high degree of regulation is involved in the protein synthesis machinery entailing more interacting regulatory factors. A multitude of proteins have been identified recently which show regulatory function upon binding to the ribosome. Here, we identify tight association of a metabolic protein aldehyde-alcohol dehydrogenase E (AdhE) with the E. coli 70S ribosome isolated from cell extract under low salt wash conditions. Cryo-EM reconstruction of the ribosome sample allows us to localize its position on the head of the small subunit, near the mRNA entrance. Our study demonstrates substantial RNA unwinding activity of AdhE which can account for the ability of ribosome to translate through downstream of at least certain mRNA helices. Thus far, in E. coli, no ribosome-associated factor has been identified that shows downstream mRNA helicase activity. Additionally, the cryo-EM map reveals interaction of another extracellular protein, outer membrane protein C (OmpC), with the ribosome at the peripheral solvent side of the 50S subunit. Our result also provides important insight into plausible functional role of OmpC upon ribosome binding. Visualization of the ribosome purified directly from the cell lysate unveils for the first time interactions of additional regulatory proteins with the ribosome. PMID:26822933

  1. E. coli metabolic protein aldehyde-alcohol dehydrogenase-E binds to the ribosome: a unique moonlighting action revealed

    PubMed Central

    Shasmal, Manidip; Dey, Sandip; Shaikh, Tanvir R.; Bhakta, Sayan; Sengupta, Jayati

    2016-01-01

    It is becoming increasingly evident that a high degree of regulation is involved in the protein synthesis machinery entailing more interacting regulatory factors. A multitude of proteins have been identified recently which show regulatory function upon binding to the ribosome. Here, we identify tight association of a metabolic protein aldehyde-alcohol dehydrogenase E (AdhE) with the E. coli 70S ribosome isolated from cell extract under low salt wash conditions. Cryo-EM reconstruction of the ribosome sample allows us to localize its position on the head of the small subunit, near the mRNA entrance. Our study demonstrates substantial RNA unwinding activity of AdhE which can account for the ability of ribosome to translate through downstream of at least certain mRNA helices. Thus far, in E. coli, no ribosome-associated factor has been identified that shows downstream mRNA helicase activity. Additionally, the cryo-EM map reveals interaction of another extracellular protein, outer membrane protein C (OmpC), with the ribosome at the peripheral solvent side of the 50S subunit. Our result also provides important insight into plausible functional role of OmpC upon ribosome binding. Visualization of the ribosome purified directly from the cell lysate unveils for the first time interactions of additional regulatory proteins with the ribosome. PMID:26822933

  2. Modeling-Dependent Protein Characterization of the Rice Aldehyde Dehydrogenase (ALDH) Superfamily Reveals Distinct Functional and Structural Features

    PubMed Central

    Kotchoni, Simeon O.; Jimenez-Lopez, Jose C.; Gao, Dongying; Edwards, Vincent; Gachomo, Emma W.; Margam, Venu M.; Seufferheld, Manfredo J.

    2010-01-01

    The completion of the rice genome sequence has made it possible to identify and characterize new genes and to perform comparative genomics studies across taxa. The aldehyde dehydrogenase (ALDH) gene superfamily encoding for NAD(P)+-dependent enzymes is found in all major plant and animal taxa. However, the characterization of plant ALDHs has lagged behind their animal- and prokaryotic-ALDH homologs. In plants, ALDHs are involved in abiotic stress tolerance, male sterility restoration, embryo development and seed viability and maturation. However, there is still no structural property-dependent functional characterization of ALDH protein superfamily in plants. In this paper, we identify members of the rice ALDH gene superfamily and use the evolutionary nesting events of retrotransposons and protein-modeling–based structural reconstitution to report the genetic and molecular and structural features of each member of the rice ALDH superfamily in abiotic/biotic stress responses and developmental processes. Our results indicate that rice-ALDHs are the most expanded plant ALDHs ever characterized. This work represents the first report of specific structural features mediating functionality of the whole families of ALDHs in an organism ever characterized. PMID:20634950

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

    PubMed Central

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

    2011-01-01

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

  4. Pigs fed camelina meal increase hepatic gene expression of cytochrome 8b1, aldehyde dehydrogenase, and thiosulfate transferase

    PubMed Central

    2014-01-01

    Camelina sativa is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids (>35%) and γ-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, is the by-product after the oil has been extracted. Camelina meal was fed to 28 d old weaned pigs at 3.7% and 7.4% until age 56 d. The camelina meal supplements in the soy based diets, improved feed efficiency but also significantly increased the liver weights. Gene expression analyses of the livers, using intra-species microarrays, identified increased expression of phase 1 and phase 2 drug metabolism enzymes. The porcine versions of the enzymes were confirmed by real time PCR. Cytochrome 8b1 (CYP8B1), aldehyde dehydrogenase 2 (Aldh2), and thiosulfate transferase (TST) were all significantly stimulated. Collectively, these genes implicate the camelina glucosinolate metabolite, methyl-sulfinyldecyl isothiocyanate, as the main xeniobiotic, causing increased hepatic metabolism and increased liver weight. PMID:24383433

  5. Aldehyde Dehydrogenase 2 (ALDH2) Polymorphism and the Risk of Alcoholic Liver Cirrhosis among East Asians: A Meta-Analysis

    PubMed Central

    He, Lei; Luo, Hesheng

    2016-01-01

    Purpose The aldehyde dehydrogenase 2 (ALDH2) gene has been implicated in the development of alcoholic liver cirrhosis (ALC) in East Asians. However, the results are inconsistent. In this study, a meta-analysis was performed to assess the associations between the ALDH2 polymorphism and the risk of ALC. Materials and Methods Relevant studies were retrieved by searching PubMed, Web of Science, CNKI, Wanfang and Veipu databases up to January 10, 2015. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using either the fixed- or random effects model. Results A total of twelve case-control studies included 1003 cases and 2011 controls were included. Overall, the ALDH2 polymorphism was associated with a decreased risk of ALC (*1/*2 vs. *1/*1: OR=0.78, 95% CI: 0.61–0.99). However, in stratification analysis by country, we failed to detect any association among Chinese, Korean or Japanese populations. Conclusion The pooled evidence suggests that ALDH2 polymorphism may be an important protective factor for ALC in East Asians. PMID:27189280

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

    SciTech Connect

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

    1990-05-01

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

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

    SciTech Connect

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

    1991-05-01

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

  8. Pigs fed camelina meal increase hepatic gene expression of cytochrome 8b1, aldehyde dehydrogenase, and thiosulfate transferase.

    PubMed

    Meadus, William Jon; Duff, Pascale; McDonald, Tanya; Caine, William R

    2014-01-01

    Camelina sativa is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids (>35%) and γ-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, is the by-product after the oil has been extracted. Camelina meal was fed to 28 d old weaned pigs at 3.7% and 7.4% until age 56 d. The camelina meal supplements in the soy based diets, improved feed efficiency but also significantly increased the liver weights. Gene expression analyses of the livers, using intra-species microarrays, identified increased expression of phase 1 and phase 2 drug metabolism enzymes. The porcine versions of the enzymes were confirmed by real time PCR. Cytochrome 8b1 (CYP8B1), aldehyde dehydrogenase 2 (Aldh2), and thiosulfate transferase (TST) were all significantly stimulated. Collectively, these genes implicate the camelina glucosinolate metabolite, methyl-sulfinyldecyl isothiocyanate, as the main xeniobiotic, causing increased hepatic metabolism and increased liver weight. PMID:24383433

  9. Solanum Incanum Extract Downregulates Aldehyde Dehydrogenase 1-Mediated Stemness and Inhibits Tumor Formation in Ovarian Cancer Cells

    PubMed Central

    Wu, Yi-Hui; Chiu, Wen-Tai; Young, Ming-Jer; Chang, Tzu-Hao; Huang, Yu-Fang; Chou, Cheng-Yang

    2015-01-01

    Solanum incanum extract (SR-T100), containing the active ingredient solamargine, can induce apoptosis via upregulation of tumor necrosis factor receptor expression and activation of the mitochondrial apoptosis pathway, and has therapeutic effects in patients with actinic keratosis. Here, we evaluate the novel molecular mechanisms underlying SR-T100-regulated stemness and chemoresistance. The concentration of SR-T100 that inhibited 50% cell viability (IC50) was lower in ovarian cancer cells than in nonmalignant cells. Furthermore, the SR-T100 IC50 in chemoresistant cells was similar to the IC50 in chemosensitive cells. Additionally, SR-T100 increased cisplatin and paclitaxel sensitivity in chemoresistant cells. SR-T100 downregulated the expression of stem cell markers, including aldehyde dehydrogenase 1 (ALDH1), Notch1, and FoxM1, and reduced sphere formation in ovarian cancer cells. Using microarray analyses, immunoblotting, luciferase activity, and chromatin immunoprecipitation (ChIP) assays, we showed that SR-T100 suppressed the expression of c/EBPβ and COL11A1, and its promoter activity, in resistant cells, but not sensitive cells. SR-T100, paclitaxel, and cisplatin inhibited the growth of A2780CP70 cells in mouse xenografts, as compared to the vehicle control, and the combination of cisplatin and SR-T100 was more effective than either treatment alone. SR-T100 may represent a potential therapeutic adjunct to chemotherapy for ovarian cancer treatment. PMID:26366215

  10. Autocrine function of aldehyde dehydrogenase 1 as a determinant of diet- and sex-specific differences in visceral adiposity.

    PubMed

    Yasmeen, Rumana; Reichert, Barbara; Deiuliis, Jeffrey; Yang, Fangping; Lynch, Alisha; Meyers, Joseph; Sharlach, Molly; Shin, Sangsu; Volz, Katharina S; Green, Kari B; Lee, Kichoon; Alder, Hansjuerg; Duester, Gregg; Zechner, Rudolf; Rajagopalan, Sanjay; Ziouzenkova, Ouliana

    2013-01-01

    Mechanisms for sex- and depot-specific fat formation are unclear. We investigated the role of retinoic acid (RA) production by aldehyde dehydrogenase 1 (Aldh1a1, -a2, and -a3), the major RA-producing enzymes, on sex-specific fat depot formation. Female Aldh1a1(-/-) mice, but not males, were resistant to high-fat (HF) diet-induced visceral adipose formation, whereas subcutaneous fat was reduced similarly in both groups. Sexual dimorphism in visceral fat (VF) was attributable to elevated adipose triglyceride lipase (Atgl) protein expression localized in clusters of multilocular uncoupling protein 1 (Ucp1)-positive cells in female Aldh1a1(-/-) mice compared with males. Estrogen decreased Aldh1a3 expression, limiting conversion of retinaldehyde (Rald) to RA. Rald effectively induced Atgl levels via nongenomic mechanisms, demonstrating indirect regulation by estrogen. Experiments in transgenic mice expressing an RA receptor response element (RARE-lacZ) revealed HF diet-induced RARE activation in VF of females but not males. In humans, stromal cells isolated from VF of obese subjects also expressed higher levels of Aldh1 enzymes compared with lean subjects. Our data suggest that an HF diet mediates VF formation through a sex-specific autocrine Aldh1 switch, in which Rald-mediated lipolysis in Ucp1-positive visceral adipocytes is replaced by RA-mediated lipid accumulation. Our data suggest that Aldh1 is a potential target for sex-specific antiobesity therapy. PMID:22933113

  11. Mitochondrial aldehyde dehydrogenase mediates vasodilator responses of glyceryl trinitrate and sodium nitrite in the pulmonary vascular bed of the rat.

    PubMed

    Badejo, Adeleke M; Hodnette, Chris; Dhaliwal, Jasdeep S; Casey, David B; Pankey, Edward; Murthy, Subramanyam N; Nossaman, Bobby D; Hyman, Albert L; Kadowitz, Philip J

    2010-09-01

    It has been reported that mitochondrial aldehyde dehydrogenase (ALDH2) catalyzes the formation of glyceryl dinitrate and inorganic nitrite from glyceryl trinitrate (GTN), leading to an increase in cGMP and vasodilation in the coronary and systemic vascular beds. However, the role of nitric oxide (NO) formed from nitrite in mediating the response to GTN in the pulmonary vascular bed is uncertain. The purpose of the present study was to determine if nitrite plays a role in mediating vasodilator responses to GTN. In this study, intravenous injections of GTN and sodium nitrite decreased pulmonary and systemic arterial pressures and increased cardiac output. The decreases in pulmonary arterial pressure under baseline and elevated tone conditions and decreases in systemic arterial pressure in response to GTN and sodium nitrite were attenuated by cyanamide, an ALDH2 inhibitor, whereas responses to the NO donor, sodium nitroprusside (SNP), were not altered. The decreases in pulmonary and systemic arterial pressure in response to GTN and SNP were not altered by allopurinol, an inhibitor of xanthine oxidoreductase, whereas responses to sodium nitrite were attenuated. GTN was approximately 1,000-fold more potent than sodium nitrite in decreasing pulmonary and systemic arterial pressures. These results suggest that ALDH2 plays an important role in the bioactivation of GTN and nitrite in the pulmonary and systemic vascular beds and that the reduction of nitrite to vasoactive NO does not play an important role in mediating vasodilator responses to GTN in the intact chest rat. PMID:20543077

  12. Mitochondrial aldehyde dehydrogenase mediates vasodilator responses of glyceryl trinitrate and sodium nitrite in the pulmonary vascular bed of the rat

    PubMed Central

    Badejo, Adeleke M.; Hodnette, Chris; Dhaliwal, Jasdeep S.; Casey, David B.; Pankey, Edward; Murthy, Subramanyam N.; Nossaman, Bobby D.; Hyman, Albert L.

    2010-01-01

    It has been reported that mitochondrial aldehyde dehydrogenase (ALDH2) catalyzes the formation of glyceryl dinitrate and inorganic nitrite from glyceryl trinitrate (GTN), leading to an increase in cGMP and vasodilation in the coronary and systemic vascular beds. However, the role of nitric oxide (NO) formed from nitrite in mediating the response to GTN in the pulmonary vascular bed is uncertain. The purpose of the present study was to determine if nitrite plays a role in mediating vasodilator responses to GTN. In this study, intravenous injections of GTN and sodium nitrite decreased pulmonary and systemic arterial pressures and increased cardiac output. The decreases in pulmonary arterial pressure under baseline and elevated tone conditions and decreases in systemic arterial pressure in response to GTN and sodium nitrite were attenuated by cyanamide, an ALDH2 inhibitor, whereas responses to the NO donor, sodium nitroprusside (SNP), were not altered. The decreases in pulmonary and systemic arterial pressure in response to GTN and SNP were not altered by allopurinol, an inhibitor of xanthine oxidoreductase, whereas responses to sodium nitrite were attenuated. GTN was ∼1,000-fold more potent than sodium nitrite in decreasing pulmonary and systemic arterial pressures. These results suggest that ALDH2 plays an important role in the bioactivation of GTN and nitrite in the pulmonary and systemic vascular beds and that the reduction of nitrite to vasoactive NO does not play an important role in mediating vasodilator responses to GTN in the intact chest rat. PMID:20543077

  13. Eukaryotic aldehyde dehydrogenase (ALDH) genes: human polymorphisms, and recommended nomenclature based on divergent evolution and chromosomal mapping.

    PubMed

    Vasiliou, V; Bairoch, A; Tipton, K F; Nebert, D W

    1999-08-01

    As currently being performed with an increasing number of superfamilies, a standardized gene nomenclature system is proposed here, based on divergent evolution, using multiple alignment analysis of all 86 eukaryotic aldehyde dehydrogenase (ALDH) amino-acid sequences known at this time. The ALDHs represent a superfamily of NAD(P)(+)-dependent enzymes having similar primary structures that oxidize a wide spectrum of endogenous and exogenous aliphatic and aromatic aldehydes. To date, a total of 54 animal, 15 plant, 14 yeast, and three fungal ALDH genes or cDNAs have been sequenced. These ALDHs can be divided into a total of 18 families (comprising 37 subfamilies), and all nonhuman ALDH genes are named here after the established human ALDH genes, when possible. An ALDH protein from one gene family is defined as having approximately < or = 40% amino-acid identity to that from another family. Two members of the same subfamily exhibit approximately > or = 60% amino-acid identity and are expected to be located at the same subchromosomal site. For naming each gene, it is proposed that the root symbol 'ALDH' denoting 'aldehyde dehydrogenase' be followed by an Arabic number representing the family and, when needed, a letter designating the subfamily and an Arabic number denoting the individual gene within the subfamily; all letters are capitalized in all mammals except mouse and fruit fly, e.g. 'human ALDH3A1 (mouse, Drosophila Aldh3a1).' It is suggested that the Human Gene Nomenclature Guidelines (http://++www.gene.ucl.ac.uk/nomenclature/guidelines.h tml) be used for all species other than mouse and Drosophila. Following these guidelines, the gene is italicized, whereas the corresponding cDNA, mRNA, protein or enzyme activity is written with upper-case letters and without italics, e.g. 'human, mouse or Drosophila ALDH3A1 cDNA, mRNA, or activity'. If an orthologous gene between species cannot be identified with certainty, sequential naming of these genes will be carried out

  14. Alcohol and Aldehyde Dehydrogenases Contribute to Sex-Related Differences in Clearance of Zolpidem in Rats

    PubMed Central

    Peer, Cody J.; Strope, Jonathan D.; Beedie, Shaunna; Ley, Ariel M.; Holly, Alesia; Calis, Karim; Farkas, Ronald; Parepally, Jagan; Men, Angela; Fadiran, Emmanuel O.; Scott, Pamela; Jenkins, Marjorie; Theodore, William H.; Sissung, Tristan M.

    2016-01-01

    Objectives: The recommended zolpidem starting dose was lowered in females (5 mg vs. 10 mg) since side effects were more frequent and severe than those of males; the mechanism underlying sex differences in pharmacokinetics (PK) is unknown. We hypothesized that such differences were caused by known sex-related variability in alcohol dehydrogenase (ADH) expression. Methods: Male, female, and castrated male rats were administered 2.6 mg/kg zolpidem, ± disulfiram (ADH/ALDH pathway inhibitor) to compare PK changes induced by sex and gonadal hormones. PK analyses were conducted in rat plasma and rat brain. Key findings: Sex differences in PK were evident: females had a higher CMAX (112.4 vs. 68.1 ug/L) and AUC (537.8 vs. 231.8 h∗ug/L) than uncastrated males. Castration induced an earlier TMAX (0.25 vs. 1 h), greater CMAX (109.1 vs. 68.1 ug/L), and a corresponding AUC increase (339.7 vs. 231.8 h∗ug/L). Administration of disulfiram caused more drastic CMAX and TMAX changes in male vs. female rats that mirrored the effects of castration on first-pass metabolism, suggesting that the observed PK differences may be caused by ADH/ALDH expression. Brain concentrations paralleled plasma concentrations. Conclusion: These findings indicate that sex differences in zolpidem PK are influenced by variation in the expression of ADH/ALDH due to gonadal androgens. PMID:27574509

  15. Alcohol oxidase is a novel pathogenicity factor for Cladosporium fulvum, but aldehyde dehydrogenase is dispensable.

    PubMed

    Segers, G; Bradshaw, N; Archer, D; Blissett, K; Oliver, R P

    2001-03-01

    Cladosporiumfulvum is a mitosporic ascomycete pathogen of tomato. A study of fungal genes expressed during carbon starvation in vitro identified several genes that were up regulated during growth in planta. These included genes predicted to encode acetaldehyde dehydrogenase (Aldh1) and alcohol oxidase (Aox1). An Aldh1 deletion mutant was constructed. This mutant lacked all detectable ALDH activity, had lost the ability to grow with ethanol as a carbon source, but was unaffected in pathogenicity. Aox1 expression was induced by carbon starvation and during the later stages of infection. The alcohol oxidase enzyme activity has broadly similar properties (Km values, substrate specificity, pH, and heat stability) to yeast enzymes. Antibodies raised to Hansenula polymorpha alcohol oxidase (AOX) detected antigens in Western blots of starved C. fulvum mycelium and infected plant material. Antigen reacting with the antibodies was localized to organelles resembling peroxisomes in starved mycelium and infected plants. Disruption mutants of Aox1 lacked detectable AOX activity and had markedly reduced pathogenicity as assayed by two different measures of fungal growth. These results identify alcohol oxidase as a novel pathogenicity factor and are discussed in relation to peroxisomal metabolism of fungal pathogens during growth in planta. PMID:11277434

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

    PubMed Central

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

    2015-01-01

    Background 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. Methods 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. Results 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). Conclusions 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

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

    PubMed Central

    2011-01-01

    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. PMID:21827695

  18. Aldehyde Dehydrogenase-2 (ALDH2) Ameliorates Chronic Alcohol Ingestion-Induced Hepatic Steatosis and Inflammation: Role of Autophagy

    PubMed Central

    Guo, Rui; Xu, Xihui; Babcock, Sara A.; Zhang, Yingmei; Ren, Jun

    2014-01-01

    Background & Aims Mitochondrial aldehyde dehydrogenase (ALDH2) plays a critical role in the detoxification of the ethanol metabolite acetaldehyde. This study was designed to examine the impact of global ALDH2 overexpression on alcohol-induced hepatic steatosis. Methods Wild-type friendly virus B (FVB) and ALDH2 transgenic mice were placed on a 4% alcohol or control diet for 12 weeks. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin and cholesterol, hepatic triglyceride, steatosis, fat metabolism-related proteins, pro-inflammatory cytokines, glutathione (GSH), oxidized glutathione (GSSG), autophagy and autophagy signaling were examined. The role of autophagy was evaluated in ADH1-transfected human hepatocellular liver carcinoma cells (VA-13) treated with or without autophagy inducer rapamycin and lysosomal inhibitors. Results Chronic alcohol intake led to elevated AST, ALT, bilirubin, AST/ALT ratio, cholesterol, hepatic triglycerides, hepatic fat deposition as evidenced by H&E and oil Red O staining, associated with disturbed fat metabolism-related proteins (fatty acid synthase, SCD1), upregulated interleukin-6, TNF-α, cyclooxygenase, oxidative stress, and loss of autophagy, the effects of which were attenuated or ablated by ALDH2 transgene. Moreover, ethanol (100 mM) and acetaldehyde (100, 500 μM) increased levels of IL-6 and IFN-γ, and suppressed autophagy in VA-13 cells, the effects of which were markedly alleviated by rapamycin. In addition, lysosomal inhibitors mimicked ethanol-induced p62 accumulation with little additive effect with ethanol. Ethanol significantly suppressed LC3 conversion in the presence of lysosomal inhibitors. Conclusions In summary, our results revealed that ALDH2 plays a beneficial role in ameliorating chronic alcohol intake-induced hepatic steatosis and inflammation through regulation of autophagy. PMID:25457208

  19. Aldehyde dehydrogenase 3A1 is robustly upregulated in gastric cancer stem-like cells and associated with tumorigenesis.

    PubMed

    Wu, Di; Mou, Yi-Ping; Chen, Ke; Cai, Jia-Qin; Zhou, Yu-Cheng; Pan, Yu; Xu, Xiao-Wu; Zhou, Wei; Gao, Jia-Qi; Chen, Ding-Wei; Zhang, Ren-Chao

    2016-08-01

    Enhanced aldehyde dehydrogenase (ALDH) activity has been shown to serve as a hallmark for cancer stem cells (CSCs). Recent evidence suggests that its role as a stem cell-related marker has come down to the specific isoform. However, little is known about the specific ALDH isoform contributing to aldefluor activity in gastric cancer. In this study, we isolated ALDHbright cells from 2 human gastric cancer cell lines MKN-45 and SGC‑7901 by using an Aldefluor assay and found elevated self-renewal, differentiation and tumorigenicity, as demonstration of stemness characteristics. We also found that ALDHbright cells expressed decreased levels of E-cadherin but increased levels of Snail and Vimentin, indication of an epithelial-mesenchymal transition (EMT) phenotype which may be responsible for the enhanced metastatic potential. Since further research and prognostic application based on ALDH prevalence require the quantification of the specific ALDH isoform, we characterized the expression of all 19 ALDH isoforms in the sorted gastric cancer cell lines by quantitative real-time polymerase chain reaction (qRT-PCR). Compared with the non-stem counterparts, robust upregulation of ALDH-3A1 was observed in these gastric cancer stem-like cells. Furthermore, we performed immunohistological analysis on 93 fixed patient gastric tumor samples and found that ALDH-3A1 expression correlated well with gastric cancer dysplasia and grades, differentiation, lymph node metastasis and cancer stage. Our data, therefore, provide strong evidence that ALDH-3A1 is a novel gastric cancer stem cell related marker with potential prognostic values and demonstrate a clear association between ALDH-3A1 prevalence and gastric cancer progression. PMID:27279633

  20. Aldehyde dehydrogenase 2 and head and neck cancer: a meta-analysis implementing a Mendelian randomization approach.

    PubMed

    Boccia, Stefania; Hashibe, Mia; Gallì, Paola; De Feo, Emma; Asakage, Takahiro; Hashimoto, Tomoko; Hiraki, Akio; Katoh, Takahiko; Nomura, Takeshi; Yokoyama, Akira; van Duijn, Cornelia M; Ricciardi, Gualtiero; Boffetta, Paolo

    2009-01-01

    Alcohol drinking at high doses is a risk factor for head and neck cancer, and exposure to acetaldehyde, the principle metabolite of alcohol, is supposed to account for the increased risk. Individuals homozygous for the 2 variant allele of aldehyde dehydrogenase 2 (ALDH2) are unable to metabolize acetaldehyde, which prevents them from alcohol drinking, whereas 1 2 have 6-fold higher blood acetaldehyde concentration postalcohol consumption with respect to 1 1. According to the concept of Mendelian randomization, because this polymorphism is distributed randomly during gamete formation, its association with head and neck cancer should be not confounded by smoking. We carried out a meta-analysis of ALDH2 and head and neck cancer searching for relevant studies on Medline and Embase up to January 31, 2008, and investigated the consistency between the expected odds ratio (OR) among drinkers from the largest pooled analysis among never smokers and the observed OR from this meta-analysis by an interaction test. Six studies were selected (945 cases, 2,917 controls). The OR of head and neck cancer among 2 2 was 0.53 [95% confidence interval (95% CI), 0.28-1.00] relative to 1 1 and 1.83 (95% CI, 1.21-2.77) among 1 2. The expected OR for head and neck cancer due to alcohol intake among 1 1 was 1.38 (95% CI, 0.88-2.17) and the observed OR among 1 1 compared with 2*2 from this meta-analysis was 1.88 (95% CI, 1.00-3.57; P for interaction = 0.43). Besides showing the effectiveness of the Mendelian randomization approach, these findings support the theory that alcohol increases head and neck cancer risk through the carcinogenic action of acetaldehyde. PMID:19124505

  1. Effects on sister chromatid exchange frequency of aldehyde dehydrogenase 2 genotype and smoking in vinyl chloride workers.

    PubMed

    Wong, R H; Wang, J D; Hsieh, L L; Du, C L; Cheng, T J

    1998-12-01

    Vinyl chloride monomer (VCM) is a human carcinogen. However, the exact mechanism of carcinogenesis remains unclear. VCM may be metabolized by cytochrome P450 2E1 (CYP2E1), aldehyde dehydrogenase 2 (ALDH2) and glutathione S-transferases (GSTs). Thus workers with inherited variant metabolic enzyme activities may have an altered risk of genotoxicity. This study was designed to investigate which risk factors might affect sister chromatid exchange (SCE) frequency in polyvinyl chloride (PVC) workers. Study subjects were 44 male workers from three PVC factories. Questionnaires were administered to obtain detailed histories of cigarette smoking, alcohol consumption, occupations, and medications. SCE frequency in peripheral lymphocytes was determined using a standardized method, and CYP2E1, GSTM1, GSTT1 and ALDH2 genotypes were identified by the polymerase chain reaction (PCR). Analysis revealed that smoking status and exposure to VCM were significantly associated with increased SCE frequency. The presence of ALDH2 1-2/2-2 genotypes was also significantly associated with an elevation of SCE frequency (9. 5 vs. 8.1, p<0.01). However, CYP2E1, GSTM1 or GSTT1 genotypes were not significantly associated with SCE frequency. When various genotypes were considered together, combination of CYP2E1 c1c2/c2c2 with ALDH2 1-2/2-2 showed an additive effect on SCE frequency. Similar results were also found for the combination of smoking with CYP2E1, or smoking with ALDH2. These results suggest that VCM workers with ALDH2 1-2/2-2 genotypes, who also smoke, may have increased risk of DNA damage. PMID:9838066

  2. Murine and Human Myogenic Cells Identified by Elevated Aldehyde Dehydrogenase Activity: Implications for Muscle Regeneration and Repair

    PubMed Central

    Vella, Joseph B.; Thompson, Seth D.; Bucsek, Mark J.; Song, Minjung; Huard, Johnny

    2011-01-01

    Background Despite the initial promise of myoblast transfer therapy to restore dystrophin in Duchenne muscular dystrophy patients, clinical efficacy has been limited, primarily by poor cell survival post-transplantation. Murine muscle derived stem cells (MDSCs) isolated from slowly adhering cells (SACs) via the preplate technique, induce greater muscle regeneration than murine myoblasts, primarily due to improved post-transplantation survival, which is conferred by their increased stress resistance capacity. Aldehyde dehydrogenase (ALDH) represents a family of enzymes with important morphogenic as well as oxidative damage mitigating roles and has been found to be a marker of stem cells in both normal and malignant tissue. In this study, we hypothesized that elevated ALDH levels could identify murine and human muscle derived cell (hMDC) progenitors, endowed with enhanced stress resistance and muscle regeneration capacity. Methodology/Principal Findings Skeletal muscle progenitors were isolated from murine and human skeletal muscle by a modified preplate technique and unfractionated enzymatic digestion, respectively. ALDHhi subpopulations isolated by fluorescence activate cell sorting demonstrated increased proliferation and myogenic differentiation capacities compared to their ALDHlo counterparts when cultivated in oxidative and inflammatory stress media conditions. This behavior correlated with increased intracellular levels of reduced glutathione and superoxide dismutase. ALDHhi murine myoblasts were observed to exhibit an increased muscle regenerative potential compared to ALDHlo myoblasts, undergo multipotent differentiation (osteogenic and chondrogenic), and were found predominately in the SAC fraction, characteristics that are also observed in murine MDSCs. Likewise, human ALDHhi hMDCs demonstrated superior muscle regenerative capacity compared to ALDHlo hMDCs. Conclusions The methodology of isolating myogenic cells on the basis of elevated ALDH activity

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

    PubMed Central

    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. Mitochondrial aldehyde dehydrogenase protects against doxorubicin cardiotoxicity through a transient receptor potential channel vanilloid 1-mediated mechanism.

    PubMed

    Ge, Wei; Yuan, Ming; Ceylan, Asli F; Wang, Xiaoming; Ren, Jun

    2016-04-01

    Cardiotoxicity is one of the major life-threatening effects encountered in cancer chemotherapy with doxorubicin and other anthracyclines. Mitochondrial aldehyde dehydrogenase (ALDH2) may alleviate doxorubicin toxicity although the mechanism remains elusive. This study was designed to evaluate the impact of ALDH2 overexpression on doxorubicin-induced myocardial damage with a focus on mitochondrial injury. Wild-type (WT) and transgenic mice overexpressing ALDH2 driven by chicken β-actin promoter were challenged with doxorubicin (15mg/kg, single i.p. injection, for 6days) and cardiac mechanical function was assessed using the echocardiographic and IonOptix systems. Western blot analysis was used to evaluate intracellular Ca(2+) regulatory and mitochondrial proteins, PKA and its downstream signal eNOS. Doxorubicin challenge altered cardiac geometry and function evidenced by enlarged left ventricular end systolic and diastolic diameters, decreased factional shortening, cell shortening and intracellular Ca(2+) rise, prolonged relengthening and intracellular Ca(2+) decay, the effects of which were attenuated by ALDH2. Doxorubicin challenge compromised mitochondrial integrity and upregulated 4-HNE and UCP-2 levels while downregulating levels of TRPV1, SERCA2a and PGC-1α, the effects of which were alleviated by ALDH2. Doxorubicin-induced cardiac functional defect and apoptosis were reversed by the TRPV1 agonist SA13353 and the ALDH-2 agonist Alda-1 whereas the TRPV1 antagonist capsazepine nullified ALDH2/Alda-1-induced protection. Doxorubicin suppressed phosphorylation of PKA and eNOS, the effect of which was reversed by ALDH2. Moreover, 4-HNE mimicked doxorubicin-induced cardiomyocyte anomalies, the effect of which was ablated by SA13353. Taken together, our results suggested that ALDH2 may rescue against doxorubicin cardiac toxicity possibly through a TRPV1-mediated protection of mitochondrial integrity. PMID:26692169

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

    PubMed

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

    2016-01-19

    Cardiac aging is characterized by accumulation of damaged proteins and decline of autophagic efficiency. Here, by forestalling SIRT1 carbonylated inactivation in aged heart, we determined the benefits of activation of aldehyde dehydrogenase 2 (ALDH2) on the autophagy. In this study, the ALDH2 KO mice progressively developed age-related heart dysfunction and showed reduction in the life span, which strongly suggests that ALDH2 ablation leads to cardiac aging. What's more, aged hearts displayed a significant decrease ALDH2 activity, resulting in accumulation of 4-HNE-protein adducts and protein carbonyls, impairment in the autophagy flux, and, consequently, deteriorated cardiac function after starvation. Sustained Alda-1 (selective ALDH2 activator) treatment increased cardiac ALDH2 activity and abrogated these effects. Using SIRT1 deficient heterozygous (Sirt1+/-) mice, we found that SIRT1 was necessary for ALDH2 activation-induced autophagy. We further demonstrated that ALDH2 activation attenuated SIRT1 carbonylation and improved SIRT1 activity, thereby increasing the deacetylation of nuclear LC3 and FoxO1. Sequentially, ALDH2 enhanced SIRT1 regulates LC3-Atg7 interaction and FoxO1 increased Rab7 expression, which were both necessary and sufficient for restoring autophagy flux. These results highlight that both accumulation of proteotoxic carbonyl stress linkage with autophagy decline contribute to heart senescence. ALDH2 activation is adequate to improve the autophagy flux by reducing the carbonyl modification on SIRT1, which in turn plays an important role in maintaining cardiac health during aging. PMID:26741505

  6. Essential role of aldehyde dehydrogenase 1A3 (ALDH1A3) for the maintenance of non-small cell lung cancer stem cells is associated with the STAT3 pathway

    PubMed Central

    Shao, Chunli; Sullivan, James P.; Girard, Luc; Augustyn, Alexander; Yenerall, Paul; Rodriguez, Jaime; Liu, Hui; Behrens, Carmen; Shay, Jerry W.; Wistuba, Ignacio I.; Minna, John D.

    2014-01-01

    Purpose Lung cancer stem cells (CSCs) with elevated aldehyde dehydrogenase (ALDH) activity are self-renewing, clonogenic and tumorigenic. The purpose of our study is to elucidate the mechanisms by which lung CSCs are regulated. Experimental Design A genome-wide gene expression analysis was performed to identify genes differentially expressed in the ALDH+ vs. ALDH− cells. RT-PCR, western blot and Aldefluor assay were used to validate identified genes. To explore the function in CSCs we manipulated their expression followed by colony and tumor formation assays. Results We identified a subset of genes that were differentially expressed in common in ALDH+ cells, among which ALDH1A3 was the most upregulated gene in ALDH+ vs. ALDH− cells. ShRNA-mediated knockdown of ALDH1A3 in NSCLCs resulted in a dramatic reduction in ALDH activity, clonogenicity and tumorigenicity, indicating that ALDH1A3 is required for tumorigenic properties. By contrast, overexpression of ALDH1A3 by itself it was not sufficient to increase tumorigenicity. The ALDH+ cells also expressed more activated Signal Transducers and Activators of Transcription 3 (STAT3) than ALDH− cells. Inhibition of STAT3 or its activator EZH2 genetically or pharmacologically diminished the level of ALDH+ cells and clonogenicity. Unexpectedly, ALDH1A3 was highly expressed in female, never smokers, well differentiated tumors, or adenocarcinoma. ALDH1A3 low expression was associated with poor overall survival. Conclusion Our data show that ALDH1A3 is the predominant ALDH isozyme responsible for ALDH activity and tumorigenicity in most NSCLCs, and that inhibiting either ALDH1A3 or the STAT3 pathway are potential therapeutic strategies to eliminate the ALDH+ subpopulation in NSCLCs. PMID:24907115

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2015-01-01

    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

  9. Genetic analysis of the phenobarbital regulation of the cytochrome P-450 2b-9 and aldehyde dehydrogenase type 2 mRNAs in mouse liver.

    PubMed Central

    Damon, M; Fautrel, A; Guillouzo, A; Corcos, L

    1996-01-01

    The aim of this study was to investigate the effect of the genetic background on the phenobarbital inducibility of cytochrome P-450 2b-9, cytochrome P-450 2b-10 and aldehyde dehydrogenase type 2 mRNAs in mice. We analysed the basal expression and the phenobarbital inducibility of both cytochrome P-450 mRNAs by semi-quantitative specific reverse transcription-PCR analyses in five inbred mouse strains (A/J,BALB/cByJ,C57BL/6J, DBA/2J and SWR/J). Male mice constitutively expressed cytochrome P-450 2b-9 and cytochrome P-450 2b-10 mRNAs, but a number of differences in their response to phenobarbital were observed. In all these mouse strains, phenobarbital induced cytochrome P-450 2b-10 mRNA whereas it could have either a positive or a negative effect on cytochrome P-450 2b-9 expression, depending on the strain and the sex of the mice. Specifically, phenobarbital increased cytochrome P-450 2b-9 expression in C57BL/6J males while it decreased it in DBA/2J mice. Interestingly, dexamethasone was able to mimic the phenobarbital effect on both cytochromes P-450 in these two strains. Aldehyde dehydrogenase type 2 mRNA was always induced by phenobarbital, except in the C57BL/6J strain. Genetic analysis revealed that the phenobarbital-inducible phenotype was either a semi-dominant or a recessive trait in F1 animals from a C57BL/6J x DBA/2J cross for the cytochrome P-450 2b-9 and the aldehyde dehydrogenase type 2 genes, respectively. This study suggests that the genetic basis for phenobarbital induction in mice depends on the target gene, and that more than one regulatory step would by involved in this response pathway. PMID:8713075

  10. Prognostic Value of Drinking Status and Aldehyde Dehydrogenase 2 Polymorphism in Patients With Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Kawakita, Daisuke; Oze, Isao; Hosono, Satoyo; Ito, Hidemi; Watanabe, Miki; Yatabe, Yasushi; Hasegawa, Yasuhisa; Murakami, Shingo; Tanaka, Hideo; Matsuo, Keitaro

    2016-01-01

    Background The association between alcohol drinking, aldehyde dehydrogenase 2 (ALDH2) polymorphism, and survival in patients with head and neck squamous cell carcinoma (HNSCC) remains unclear. Methods We performed a retrospective cohort study of 267 HNSCC patients at Aichi Cancer Center. Of these, 65 patients (24%) were non-drinkers, 104 (39%) were light drinkers (ethanol <46 g or <5 days/week), 46 (17%) were moderate drinkers (ethanol intake 46–68 g/day and ≥5 days/week), and 52 (20%) were heavy drinkers (ethanol intake ≥69 g and ≥5 days/week). The prognostic value of pre-treatment drinking status and ALDH2 polymorphism was investigated using multivariate proportional hazard models. Results Drinking status was associated with disease-free survival (DFS) in HNSCC patients, with marginal statistical significance (5-year DFS: 67.9% [95% confidence interval {CI}, 53.8–78.4%] for non-drinkers, 57.6% [95% CI, 47.4–66.6%] for light drinkers, 46.1% [95% CI, 30.8–60.1%] for moderate drinkers, and 43.5% [95% CI, 29.3–56.9%] for heavy drinkers; P = 0.088). However, this association lost significance when multivariate analyses were adjusted for established prognostic factors. ALDH2 genotype was not significantly associated with DFS in HNSCC patients (5-year DFS: 85.7% [95% CI, 53.9–96.2%] for Lys/Lys, 56.2% [95% CI, 47.4–64.1%] for Glu/Lys, and 50.5% [95% CI, 40.3–59.7%] for Glu/Glu; P = 0.154). After stratification by ALDH2 genotype, we observed a significant positive dose-response relationship between drinking status and DFS in HNSCC patients with ALDH2 Glu/Glu (P trend = 0.029). Conclusions In this study, we identified a significant positive dose-response relationship between pre-treatment drinking status and DFS in HNSCC patients with ALDH2 Glu/Glu. To confirm this association, further study is warranted. PMID:26804037

  11. Increased Expression of Aldehyde Dehydrogenase 2 Reduces Renal Cell Apoptosis During Ischemia/Reperfusion Injury After Hypothermic Machine Perfusion.

    PubMed

    Zhong, Zibiao; Hu, Qianchao; Fu, Zhen; Wang, Ren; Xiong, Yan; Zhang, Yang; Liu, Zhongzhong; Wang, Yanfeng; Ye, Qifa

    2016-06-01

    Hypothermic machine perfusion (MP) can reduce graft's injury after kidney transplantation; however, the mechanism has not been elucidated. In the past decade, many studies showed that aldehyde dehydrogenase 2 (ALDH2) is a protease which can inhibit cell apoptosis. Therefore, this study aims to explore whether ALDH2 takes part in reducing organ damage after MP. Eighteen healthy male New Zealand rabbits (12 weeks old, weight 3.0 ± 0.3 kg) were randomly divided into three groups: normal group, MP group, and cold storage (CS) group (n = 6). The left kidney of rabbits underwent warm ischemia for 35 min through clamping the left renal pedicle and then reperfusion for 1 h. Left kidneys were preserved by MP or CS (4°C for 4 h) in vivo followed by the right nephrectomy and 24-h reperfusion, and then the specimens and blood were collected. Finally, concentration of urine creatinine (Cr), blood urea nitrogen (BUN), and 4-HNE were tested. Renal apoptosis was detected by TUNEL staining, and the expression of ALDH2, cleaved-caspase 3, bcl-2/ bax, MAPK in renal tissue was detected by immunohistochemistry or Western blot; 24 h after surgery, the concentration of Cr in MP group was 355 ± 71μmol/L, in CS group was 511 ± 44 μmol/L (P < 0.05), while the BUN was 15.02 ± 2.34 mmol/L in MP group, 22.64 ± 3.58 mmol/L in CS group (P < 0.05). The rate of apoptosis and expression of cleaved caspase-3, p-P38, p-ERK, and p-JNK in MP group was significantly lower than that in CS group (P < 0.05), while expression of ALDH2 and bcl-2/bax in MP group was significantly higher than that in CS group (P < 0.05); expression of cleaved caspase-3 in both MP and CS group significantly increased as compared with that in normal group (P < 0.05). In conclusion, increased expression of ALDH2 can reduce the renal cell apoptosis through inhibiting MAPK pathway during ischemia/reperfusion injury (IRI) after hypothermic MP. PMID:26582147

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

    PubMed Central

    2014-01-01

    Introduction 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. Methods 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. Results 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

  13. In vivo ethanol elimination in man, monkey and rat: A lack of relationship between the ethanol metabolism and the hepatic activities of alcohol and aldehyde dehydrogenases

    SciTech Connect

    Zorzano, A. ); Herrera, E. )

    1990-01-01

    The in vivo ethanol elimination in human subjects, monkeys and rats was investigated after an oral ethanol dosage. After 0.4 g. ethanol/kg of body weight, ethanol elimination was much slower in human subjects than in monkeys. In order to detect a rise in monkey plasma ethanol concentrations as early as observed in human subjects, ethanol had to be administered at a dose of 3 g/kg body weight. Ethanol metabolism in rats was also much faster than in human subjects. However, human liver showed higher alcohol dehydrogenase activity and higher low Km aldehyde dehydrogenase activity than rat liver. Thus, our data suggest a lack of relationship between hepatic ethanol-metabolizing activities and the in vivo ethanol elimination rate.

  14. Pepper aldehyde dehydrogenase CaALDH1 interacts with Xanthomonas effector AvrBsT and promotes effector-triggered cell death and defence responses.

    PubMed

    Kim, Nak Hyun; Hwang, Byung Kook

    2015-06-01

    Xanthomonas type III effector AvrBsT induces hypersensitive cell death and defence responses in pepper (Capsicum annuum) and Nicotiana benthamiana. Little is known about the host factors that interact with AvrBsT. Here, we identified pepper aldehyde dehydrogenase 1 (CaALDH1) as an AvrBsT-interacting protein. Bimolecular fluorescence complementation and co-immunoprecipitation assays confirmed the interaction between CaALDH1 and AvrBsT in planta. CaALDH1:smGFP fluorescence was detected in the cytoplasm. CaALDH1 expression in pepper was rapidly and strongly induced by avirulent Xanthomonas campestris pv. vesicatoria (Xcv) Ds1 (avrBsT) infection. Transient co-expression of CaALDH1 with avrBsT significantly enhanced avrBsT-triggered cell death in N. benthamiana leaves. Aldehyde dehydrogenase activity was higher in leaves transiently expressing CaALDH1, suggesting that CaALDH1 acts as a cell death enhancer, independently of AvrBsT. CaALDH1 silencing disrupted phenolic compound accumulation, H2O2 production, defence response gene expression, and cell death during avirulent Xcv Ds1 (avrBsT) infection. Transgenic Arabidopsis thaliana overexpressing CaALDH1 exhibited enhanced defence response to Pseudomonas syringae pv. tomato and Hyaloperonospora arabidopsidis infection. These results indicate that cytoplasmic CaALDH1 interacts with AvrBsT and promotes plant cell death and defence responses. PMID:25873668

  15. Aldehyde dehydrogenase type 2 activation by adenosine and histamine inhibits ischemic norepinephrine release in cardiac sympathetic neurons: mediation by protein kinase Cε.

    PubMed

    Robador, Pablo A; Seyedi, Nahid; Chan, Noel Yan-Ki; Koda, Kenichiro; Levi, Roberto

    2012-10-01

    During myocardial ischemia/reperfusion, lipid peroxidation leads to the formation of toxic aldehydes that contribute to ischemic dysfunction. Mitochondrial aldehyde dehydrogenase type 2 (ALDH2) alleviates ischemic heart damage and reperfusion arrhythmias via aldehyde detoxification. Because excessive norepinephrine release in the heart is a pivotal arrhythmogenic mechanism, we hypothesized that neuronal ALDH2 activation might diminish ischemic norepinephrine release. Incubation of cardiac sympathetic nerve endings with acetaldehyde, at concentrations achieved in myocardial ischemia, caused a concentration-dependent increase in norepinephrine release. A major increase in norepinephrine release also occurred when sympathetic nerve endings were incubated in hypoxic conditions. ALDH2 activation substantially reduced acetaldehyde- and hypoxia-induced norepinephrine release, an action prevented by inhibition of ALDH2 or protein kinase Cε (PKCε). Selective activation of G(i/o)-coupled adenosine A(1), A(3), or histamine H(3) receptors markedly inhibited both acetaldehyde- and hypoxia-induced norepinephrine release. These effects were also abolished by PKCε and/or ALDH2 inhibition. Moreover, A(1)-, A(3)-, or H(3)-receptor activation increased ALDH2 activity in a sympathetic neuron model (differentiated PC12 cells stably transfected with H(3) receptors). This action was prevented by the inhibition of PKCε and ALDH2. Our findings suggest the existence in sympathetic neurons of a protective pathway initiated by A(1)-, A(3)-, and H(3)-receptor activation by adenosine and histamine released in close proximity of these terminals. This pathway comprises the sequential activation of PKCε and ALDH2, culminating in aldehyde detoxification and inhibition of hypoxic norepinephrine release. Thus, pharmacological activation of PKCε and ALDH2 in cardiac sympathetic nerves may have significant protective effects by alleviating norepinephrine-induced life-threatening arrhythmias that

  16. Histamine H4-receptors inhibit mast cell renin release in ischemia/reperfusion via protein kinase C ε-dependent aldehyde dehydrogenase type-2 activation.

    PubMed

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

    2014-06-01

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

  17. Ergot alkaloid biosynthesis in Aspergillus fumigatus: conversion of chanoclavine-I to chanoclavine-I aldehyde catalyzed by a short-chain alcohol dehydrogenase FgaDH.

    PubMed

    Wallwey, Christiane; Matuschek, Marco; Li, Shu-Ming

    2010-02-01

    Ergot alkaloids are toxins and important pharmaceuticals which are produced biotechnologically on an industrial scale. A putative gene fgaDH has been identified in the biosynthetic gene cluster of fumigaclavine C, an ergot alkaloid of the clavine-type. The deduced gene product FgaDH comprises 261 amino acids with a molecular mass of about 27.8 kDa and contains the conserved motifs of classical short-chain dehydrogenases/reductases (SDRs), but shares no worth mentioning sequence similarity with SDRs and other known proteins. The coding region of fgaDH consisting of two exons was amplified by PCR from a cDNA library of Aspergillus fumigatus, cloned into pQE60 and overexpressed in E. coli. The soluble tetrameric His(6)-FgaDH was purified to apparent homogeneity and characterized biochemically. It has been shown that FgaDH catalyzes the oxidation of chanoclavine-I in the presence of NAD(+) resulting in the formation of chanoclavine-I aldehyde, which was unequivocally identified by NMR and MS analyzes. Therefore, FgaDH functions as a chanoclavine-I dehydrogenase and represents a new group of short-chain dehydrogenases. K (M) values for chanoclavine-I and NAD(+) were determined at 0.27 and 1.1 mM, respectively. The turnover number was 0.38 s(-1). PMID:20039019

  18. Characterization of the Saccharomyces cerevisiae YMR318C (ADH6) gene product as a broad specificity NADPH-dependent alcohol dehydrogenase: relevance in aldehyde reduction.

    PubMed Central

    Larroy, Carol; Fernández, M Rosario; González, Eva; Parés, Xavier; Biosca, Josep A

    2002-01-01

    YMR318C represents an open reading frame from Saccharomyces cerevisiae with unknown function. It possesses a conserved sequence motif, the zinc-containing alcohol dehydrogenase (ADH) signature, specific to the medium-chain zinc-containing ADHs. In the present study, the YMR318C gene product has been purified to homogeneity from overexpressing yeast cells, and found to be a homodimeric ADH, composed of 40 kDa subunits and with a pI of 5.0-5.4. The enzyme was strictly specific for NADPH and was active with a wide variety of substrates, including aliphatic (linear and branched-chain) and aromatic primary alcohols and aldehydes. Aldehydes were processed with a 50-fold higher catalytic efficiency than that for the corresponding alcohols. The highest k(cat)/K(m) values were found with pentanal>veratraldehyde > hexanal > 3-methylbutanal >cinnamaldehyde. Taking into consideration the substrate specificity and sequence characteristics of the YMR318C gene product, we have proposed this gene to be called ADH6. The disruption of ADH6 was not lethal for the yeast under laboratory conditions. Although S. cerevisiae is considered a non lignin-degrading organism, the catalytic activity of ADHVI can direct veratraldehyde and anisaldehyde, arising from the oxidation of lignocellulose by fungal lignin peroxidases, to the lignin biodegradation pathway. ADHVI is the only S. cerevisiae enzyme able to significantly reduce veratraldehyde in vivo, and its overexpression allowed yeast to grow under toxic concentrations of this aldehyde. The enzyme may also be involved in the synthesis of fusel alcohols. To our knowledge this is the first NADPH-dependent medium-chain ADH to be characterized in S. cerevisiae. PMID:11742541

  19. Molecular and Catalytic Properties of the Aldehyde Dehydrogenase of Gluconacetobacter diazotrophicus, a Quinoheme Protein Containing Pyrroloquinoline Quinone, Cytochrome b, and Cytochrome c▿

    PubMed Central

    Gómez-Manzo, S.; Chavez-Pacheco, J. L.; Contreras-Zentella, M.; Sosa-Torres, M. E.; Arreguín-Espinosa, R.; Pérez de la Mora, M.; Membrillo-Hernández, J.; Escamilla, J. E.

    2010-01-01

    Several aldehyde dehydrogenase (ALDH) complexes have been purified from the membranes of acetic acid bacteria. The enzyme structures and the chemical nature of the prosthetic groups associated with these enzymes remain a matter of debate. We report here on the molecular and catalytic properties of the membrane-bound ALDH complex of the diazotrophic bacterium Gluconacetobacter diazotrophicus. The purified ALDH complex is a heterodimer comprising two subunits of 79.7 and 50 kDa, respectively. Reversed-phase high-pressure liquid chromatography (HPLC) and electron paramagnetic resonance spectroscopy led us to demonstrate, for the first time, the unequivocal presence of a pyrroloquinoline quinone prosthetic group associated with an ALDH complex from acetic acid bacteria. In addition, heme b was detected by UV-visible light (UV-Vis) spectroscopy and confirmed by reversed-phase HPLC. The smaller subunit bears three cytochromes c. Aliphatic aldehydes, but not formaldehyde, were suitable substrates. Using ferricyanide as an electron acceptor, the enzyme showed an optimum pH of 3.5 that shifted to pH 7.0 when phenazine methosulfate plus 2,6-dichlorophenolindophenol were the electron acceptors. Acetaldehyde did not reduce measurable levels of the cytochrome b and c centers; however, the dithionite-reduced hemes were conveniently oxidized by ubiquinone-1; this finding suggests that cytochrome b and the cytochromes c constitute an intramolecular redox sequence that delivers electrons to the membrane ubiquinone. PMID:20802042

  20. Molecular characterization and organ-specific expression of the gene that encodes betaine aldehyde dehydrogenase from the white shrimp Litopenaeus vannamei in response to osmotic stress.

    PubMed

    Delgado-Gaytán, María F; Hernández-Palomares, Magally L E; Soñanez-Organis, José G; Muhlia-Almazán, Adriana; Sánchez-Paz, Arturo; Stephens-Camacho, Norma A; Valenzuela-Soto, Elisa M; Rosas-Rodríguez, Jesús A

    2015-11-01

    Crustaceans overcome osmotic disturbances by regulating their intracellular concentration of ions and osmolytes. Glycine betaine (GB), an osmolyte accumulated in response to hyperosmotic stress, is synthesized by betaine aldehyde dehydrogenase (BADH EC 1.2.1.8) through the oxidation of betaine aldehyde. A partial BADH cDNA sequence from the white shrimp Litopenaeus vannamei was obtained and its organ-specific expression during osmotic stress (low and high salinity) was evaluated. The partial BADH cDNA sequence (LvBADH) is 1103bp long and encodes an open reading frame for 217 protein residues. The amino acid sequence of LvBADH is related to that of other BADHs, TMABA-DH and ALDH9 from invertebrate and vertebrate homologues, and includes the essential domains of their function and regulation. LvBADH activity and mRNA expression were detected in the gills, hepatopancreas and muscle with the highest levels in the hepatopancreas. LvBADH mRNA expression increased 2-3-fold in the hepatopancreas and gills after 7days of osmotic variation (25 and 40ppt). In contrast, LvBADH mRNA expression in muscle decreased 4-fold and 15-fold after 7days at low and high salinity, respectively. The results indicate that LvBADH is ubiquitously expressed, but its levels are organ-specific and regulated by osmotic stress, and that LvBADH is involved in the cellular response of crustaceans to variations in environmental salinity. PMID:26219579

  1. Sca-1+ cells from fetal heart with high aldehyde dehydrogenase activity exhibit enhanced gene expression for self-renewal, proliferation, and survival.

    PubMed

    Dey, Devaveena; Pan, Guodong; Varma, Nadimpalli Ravi S; Palaniyandi, Suresh Selvaraj

    2015-01-01

    Stem/progenitor cells from multiple tissues have been isolated based on enhanced activity of cytosolic aldehyde dehydrogenase (ALDH) enzyme. ALDH activity has emerged as a reliable marker for stem/progenitor cells, such that ALDH(bright/high) cells from multiple tissues have been shown to possess enhanced stemness properties (self-renewal and multipotency). So far though, not much is known about ALDH activity in specific fetal organs. In this study, we sought to analyze the presence and activity of the ALDH enzyme in the stem cell antigen-1-positive (Sca-1+) cells of fetal human heart. Biochemical assays showed that a subpopulation of Sca-1+ cells (15%) possess significantly high ALDH1 activity. This subpopulation showed increased expression of self-renewal markers compared to the ALDH(low) fraction. The ALDH(high) fraction also exhibited significant increase in proliferation and pro-survival gene expression. In addition, only the ALDH(high) and not the ALDH(low) fraction could give rise to all the cell types of the original population, demonstrating multipotency. ALDH(high) cells showed increased resistance against aldehyde challenge compared to ALDH(low) cells. These results indicate that ALDH(high) subpopulation of the cultured human fetal cells has enhanced self-renewal, multipotency, high proliferation, and survival, indicating that this might represent a primitive stem cell population within the fetal human heart. PMID:25861413

  2. Exploring the evolutionary route of the acquisition of betaine aldehyde dehydrogenase activity by plant ALDH10 enzymes: implications for the synthesis of the osmoprotectant glycine betaine

    PubMed Central

    2014-01-01

    Background Plant ALDH10 enzymes are aminoaldehyde dehydrogenases (AMADHs) that oxidize different ω-amino or trimethylammonium aldehydes, but only some of them have betaine aldehyde dehydrogenase (BADH) activity and produce the osmoprotectant glycine betaine (GB). The latter enzymes possess alanine or cysteine at position 441 (numbering of the spinach enzyme, SoBADH), while those ALDH10s that cannot oxidize betaine aldehyde (BAL) have isoleucine at this position. Only the plants that contain A441- or C441-type ALDH10 isoenzymes accumulate GB in response to osmotic stress. In this work we explored the evolutionary history of the acquisition of BAL specificity by plant ALDH10s. Results We performed extensive phylogenetic analyses and constructed and characterized, kinetically and structurally, four SoBADH variants that simulate the parsimonious intermediates in the evolutionary pathway from I441-type to A441- or C441-type enzymes. All mutants had a correct folding, average thermal stabilities and similar activity with aminopropionaldehyde, but whereas A441S and A441T exhibited significant activity with BAL, A441V and A441F did not. The kinetics of the mutants were consistent with their predicted structural features obtained by modeling, and confirmed the importance of position 441 for BAL specificity. The acquisition of BADH activity could have happened through any of these intermediates without detriment of the original function or protein stability. Phylogenetic studies showed that this event occurred independently several times during angiosperms evolution when an ALDH10 gene duplicate changed the critical Ile residue for Ala or Cys in two consecutive single mutations. ALDH10 isoenzymes frequently group in two clades within a plant family: one includes peroxisomal I441-type, the other peroxisomal and non-peroxisomal I441-, A441- or C441-type. Interestingly, high GB-accumulators plants have non-peroxisomal A441- or C441-type isoenzymes, while low-GB accumulators

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

    PubMed

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

    2014-09-01

    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. PMID:25137435

  4. Evidence That the C-Terminal Domain of a Type B PutA Protein Contributes to Aldehyde Dehydrogenase Activity and Substrate Channeling

    PubMed Central

    2015-01-01

    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 Δ1-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. PMID:25137435

  5. Expression of a heat-stable NADPH-dependent alcohol dehydrogenase in Caldicellulosiruptor bescii results in furan aldehyde detoxification

    SciTech Connect

    Chung, Daehwan; Verbeke, Tobin J.; Cross, Karissa L.; Westpheling, Janet; Elkins, James G.

    2015-07-22

    Compounds such as furfural and 5-hydroxymethylfurfural (5-HMF) are generated through the dehydration of xylose and glucose, respectively, during dilute-acid pretreatment of lignocellulosic biomass and are also potent microbial growth and fermentation inhibitors. The enzymatic reduction of these furan aldehydes to their corresponding, and less toxic, alcohols is an engineering approach that has been successfully implemented in both Saccharomyces cerevisiae and ethanologenicEscherichia coli, but has not yet been investigated in thermophiles relevant to biofuel production through consolidated bioprocessing (CBP). Developing CBP-relevant biocatalysts that are either naturally resistant to such inhibitors, or are amenable to engineered resistance, is therefore, an important component in making biofuels production from lignocellulosic biomass feasible.

  6. Expression of a heat-stable NADPH-dependent alcohol dehydrogenase in Caldicellulosiruptor bescii results in furan aldehyde detoxification

    DOE PAGESBeta

    Chung, Daehwan; Verbeke, Tobin J.; Cross, Karissa L.; Westpheling, Janet; Elkins, James G.

    2015-07-22

    Compounds such as furfural and 5-hydroxymethylfurfural (5-HMF) are generated through the dehydration of xylose and glucose, respectively, during dilute-acid pretreatment of lignocellulosic biomass and are also potent microbial growth and fermentation inhibitors. The enzymatic reduction of these furan aldehydes to their corresponding, and less toxic, alcohols is an engineering approach that has been successfully implemented in both Saccharomyces cerevisiae and ethanologenicEscherichia coli, but has not yet been investigated in thermophiles relevant to biofuel production through consolidated bioprocessing (CBP). Developing CBP-relevant biocatalysts that are either naturally resistant to such inhibitors, or are amenable to engineered resistance, is therefore, an important componentmore » in making biofuels production from lignocellulosic biomass feasible.« less

  7. Conversion of Suspected Food Carcinogen 5-Hydroxymethylfurfural by Sulfotransferases and Aldehyde Dehydrogenases in Postmitochondrial Tissue Preparations of Humans, Mice, and Rats.

    PubMed

    Sachse, Benjamin; Meinl, Walter; Glatt, Hansruedi; Monien, Bernhard H

    2016-01-01

    The food contaminant 5-hydroxymethylfurfural (HMF) is formed by heat- and acid-catalyzed reactions from carbohydrates. More than 80% of HMF is metabolized by oxidation of the aldehyde group in mice and rats. Sulfo conjugation yields mutagenic 5-sulfoxymethylfurfural, the probable cause for the neoplastic effects observed in HMF-treated rodents. Considerable metabolic differences between species hinder assessing the tumorigenic risk associated with human dietary HMF uptake. Here, we assayed HMF turnover catalyzed by sulfotransferases or by aldehyde dehydrogenases (ALDHs) in postmitochondrial preparations from liver, kidney, colon, and lung of humans, mice, and rats. The tissues-specific clearance capacities of HMF sulfo conjugation (CL(SC)) and ALDH-catalyzed oxidation (CL(OX)) were concentrated to the liver. The hepatic clearance CL(SC) in mice (males: 487 µl/min/kg bw, females: 2520 µl/min/kg bw) and rats (males: 430 µl/min/kg bw, females: 198 µl/min/kg bw) were considerably higher than those in humans (males: 21.2 µl/min/kg bw, females: 32.2 µl/min/kg bw). The ALDH-related clearance rates CLOX in mice (males: 3400 ml/min/kg bw, females: 1410 ml/min/kg bw) were higher than those of humans (males: 436 ml/min/kg bw, females: 646 ml/min/kg bw) and rats (males: 627 ml/min/kg bw, females: 679 ml/min/kg bw). The ratio of CL(OX) to CL(SC) was lowest in female mice. This finding indicated that HMF sulfo conjugation was most substantial in the liver of female mice, a target tissue for HMF-induced neoplastic effects, and that humans may be less sensitive regarding HMF sulfo conjugation compared with the rodent models. PMID:26454887

  8. Development of Selective Inhibitors for Human Aldehyde Dehydrogenase 3A1 (ALDH3A1) for the Enhancement of Cyclophosphamide Cytotoxicity

    PubMed Central

    Parajuli, Bibek; Georgiadis, Taxiarchis M.; Fishel, Melissa L.; Hurley, Thomas D.

    2014-01-01

    Aldehyde dehydrogenase 3A1 (ALDH3A1) plays an important role in many cellular oxidative processes, including cancer chemo-resistance by metabolizing activated forms of oxazaphosphorine drugs such as cyclophosphamide (CP) and its analogues such as mafosfamide (MF), ifosfamide (IFM), 4-hydroperoxycyclophosphamide (4-HPCP). Compounds that can selectively target ALDH3A1 may permit delineation of its roles in these processes and could restore chemosensitivity in cancer cells that express this isoenzyme. Here we report the detailed kinetic and structural characterization of an ALDH3A1 selective inhibitor, CB29, previously identified in a high throughput screen. Kinetic and crystallographic studies demonstrate that CB29 binds within the aldehyde substrate-binding site of ALDH3A1. Cellular proliferation of ALDH3A1-expressing lung adenocarcinoma (A549) and glioblastoma (SF767) cell lines, as well as the ALDH3A1 non-expressing lung fibroblast cells, CCD-13Lu, is unaffected by treatment with CB29 and its analogues alone. However, the sensitivity toward the anti-proliferative effects of mafosfamide is enhanced by treatment with CB29 and its analogue in the tumour cells. In contrast, the sensitivity of CCD-13Lu cells toward mafosfamide was unaffected by the addition of these same compounds. CB29 is chemically distinct from the previously reported small molecule inhibitors of ALDH isoenzymes and does not inhibit ALDH1A1, ALDH1A2, ALDH1A3, ALDH1B1 or ALDH2 isoenzymes at concentrations up to 250 μM. Thus, CB29 is a novel small molecule inhibitor of ALDH3A1, which may be useful as a chemical tool to delineate the role of ALDH3A1 in numerous metabolic pathways, including sensitizing ALDH3A1-positive cancer cells to oxazaphosphorines. PMID:24677340

  9. The impact of mitochondrial aldehyde dehydrogenase (ALDH2) activation by Alda-1 on the behavioral and biochemical disturbances in animal model of depression.

    PubMed

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

    2016-01-01

    The etiology of depression remains still unclear. Recently, it has been proposed, that mitochondrial dysfunction may be associated with development of mood disorders, such as depression, bipolar disorder and anxiety disorders. Mitochondrial aldehyde dehydrogenase (ALDH2), an enzyme responsible for the detoxification of reactive aldehydes, is considered to exert protective function in mitochondria. We investigated the influence of Alda-1, a small-molecule activator of ALDH2, on depressive- and anxiety-like behaviors in an animal model of depression - the prenatally stressed rats - using behavioral, molecular and proteomic methods. Prolonged Alda-1 administration significantly increased the climbing time, tended to reduce the immobility time and increased the swimming time of the prenatally stressed rats in the forced swim test. Moreover, treatment of prenatally stressed rats with Alda-1 significantly increased number of entries into the open arms of the maze and the time spent therein, as assessed by elevated plus-maze test. Such actions were associated with reduction of plasma 4-HNE-protein content, decrease of TNF-α mRNA and increase of PGC-1α (regulator of mitochondrial biogenesis) mRNA level in the frontal cortex and hippocampus of the prenatally stressed rats as well as with normalization of peripheral immune parameters and significant changes in expression of 6 and 4 proteins related to mitochondrial functions in the frontal cortex and hippocampus, respectively. Collectively, ALDH2 activation by Alda-1 led to a significant attenuation of depressive- and anxiety-like behaviors in the prenatally stressed rats. The pattern of changes suggested mitoprotective effect of Alda-1, however the exact functional consequences of the revealed alterations require further investigation. PMID:26254233

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

    PubMed

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

    2015-05-01

    Previous studies have reported that aspirin significantly reduced the first-pass metabolism (FPM) of ethanol in humans thereby increasing adverse effects of alcohol. The underlying causes, however, remain poorly understood. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), principal enzymes responsible for metabolism of ethanol, are complex enzyme families that exhibit functional polymorphisms among ethnic groups and distinct tissue distributions. We investigated the inhibition profiles by aspirin and its major metabolite salicylate of ethanol oxidation by recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and acetaldehyde oxidation by ALDH1A1 and ALDH2, at pH 7.5 and 0.5 mM NAD(+). Competitive inhibition pattern was found to be a predominant type among the ADHs and ALDHs studied, although noncompetitive and uncompetitive inhibitions were also detected in a few cases. The inhibition constants of salicylate for the ADHs and ALDHs were considerably lower than that of aspirin with the exception of ADH1A that can be ascribed to a substitution of Ala-93 at the bottom of substrate pocket as revealed by molecular docking experiments. Kinetic inhibition equation-based simulations show at higher therapeutic levels of blood plasma salicylate (1.5 mM) that the decrease of activities at 2-10 mM ethanol for ADH1A/ADH2 and ADH1B2/ADH1B3 are predicted to be 75-86% and 31-52%, respectively, and that the activity decline for ALDH1A1 and ALDH2 at 10-50 μM acetaldehyde to be 62-73%. Our findings suggest that salicylate may substantially inhibit hepatic FPM of alcohol at both the ADH and ALDH steps when concurrent intaking aspirin. PMID:25772736

  11. The absence of aldehyde dehydrogenase 1 A1-positive cells in benign mammary stroma is associated with risk factors for breast cancer

    PubMed Central

    Isfoss, Björn Logi; Holmqvist, Bo; Jernström, Helena; Alm, Per; Olsson, Håkan

    2016-01-01

    In this study, aldehyde dehydrogenase 1 (ALDH1)-expressing cells in stroma of histologically normal breast tissue from premenopausal women were investigated in situ regarding cellular morphology, cell distribution, and relation to the additional stem cell markers, CD44 (+) and CD24 (−). These results were correlated with hormonal and genetic risk factors for breast cancer. Triple immunofluorescence labeling was performed on tissues from premenopausal women with a family history of breast cancer, and breast reduction specimens from premenopausal women with no family history of breast cancer were used as a control group. The majority of ALDH1-immunoreactive cells in stroma were spindle-shaped or polygonal, and such cells that were CD44− and CD24− were absent in the breast stroma of a significantly larger number of nulliparous than parous women. A less common morphological type of ALDH1-positive cells in stroma was round or oval in shape, and such cells that were CD44+ and CD24− were absent in a significant number of women with a family history of breast cancer. The CD44+/CD24− immunophenotype is consistent with stem cells, and the round/oval morphology suggests mesenchymal cells. This study demonstrates that there are two morphologically distinct types of ALDH1-positive cells in histologically benign mammary stroma, and the absence of these cells is correlated with clinical risk factors for breast cancer in premenopausal women. PMID:27313475

  12. Two clinical drugs deubiquitinase inhibitor auranofin and aldehyde dehydrogenase inhibitor disulfiram trigger synergistic anti-tumor effects in vitro and in vivo.

    PubMed

    Huang, Hongbiao; Liao, Yuning; Liu, Ningning; Hua, Xianliang; Cai, Jianyu; Yang, Changshan; Long, Huidan; Zhao, Chong; Chen, Xin; Lan, Xiaoying; Zang, Dan; Wu, Jinjie; Li, Xiaofen; Shi, Xianping; Wang, Xuejun; Liu, Jinbao

    2016-01-19

    Inhibition of proteasome-associated deubiquitinases (DUBs) is emerging as a novel strategy for cancer therapy. It was recently reported that auranofin (Aur), a gold (I)-containing compound used clinically to treat rheumatoid arthritis, is a proteasome-associated DUB inhibitor. Disulfiram (DSF), an inhibitor of aldehyde dehydrogenase, is currently in clinical use for treating alcoholism. Recent studies have indicated that DSF can also act as an antitumor agent. We investigated the effect of combining DSF and Aur on apoptosis induction and tumor growth in hepatoma cancer cells. Here we report that (i) the combined treatment of Aur and DSF results in synergistic cytotoxicity to hepatoma cells in vitro and in vivo; (ii) Aur and DSF in combination induces caspase activation, endoplasmic reticulum (ER) stress, and reactive oxygen species (ROS) production; (iii) pan-caspase inhibitor z-VAD-FMK could efficiently block apoptosis but not proteasome inhibition induced by Aur and DSF combined treatment, and ROS is not required for Aur+DSF to induce apoptosis. Collectively, we demonstrate a model of synergism between DSF and proteasome-associated DUB inhibitor Aur in the induction of apoptosis in hepatoma cancer cells, identifying a potential novel anticancer strategy for clinical use in the future. PMID:26625200

  13. The absence of aldehyde dehydrogenase 1 A1-positive cells in benign mammary stroma is associated with risk factors for breast cancer.

    PubMed

    Isfoss, Björn Logi; Holmqvist, Bo; Jernström, Helena; Alm, Per; Olsson, Håkan

    2016-01-01

    In this study, aldehyde dehydrogenase 1 (ALDH1)-expressing cells in stroma of histologically normal breast tissue from premenopausal women were investigated in situ regarding cellular morphology, cell distribution, and relation to the additional stem cell markers, CD44 (+) and CD24 (-). These results were correlated with hormonal and genetic risk factors for breast cancer. Triple immunofluorescence labeling was performed on tissues from premenopausal women with a family history of breast cancer, and breast reduction specimens from premenopausal women with no family history of breast cancer were used as a control group. The majority of ALDH1-immunoreactive cells in stroma were spindle-shaped or polygonal, and such cells that were CD44(-) and CD24(-) were absent in the breast stroma of a significantly larger number of nulliparous than parous women. A less common morphological type of ALDH1-positive cells in stroma was round or oval in shape, and such cells that were CD44(+) and CD24(-) were absent in a significant number of women with a family history of breast cancer. The CD44(+)/CD24(-) immunophenotype is consistent with stem cells, and the round/oval morphology suggests mesenchymal cells. This study demonstrates that there are two morphologically distinct types of ALDH1-positive cells in histologically benign mammary stroma, and the absence of these cells is correlated with clinical risk factors for breast cancer in premenopausal women. PMID:27313475

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

    SciTech Connect

    Short, Duncan M.; Lyon, Robert; Watson, David G.; Barski, Oleg A.; McGarvie, Gail; Ellis, Elizabeth M. . E-mail: Elizabeth.ellis@strath.ac.uk

    2006-01-15

    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 {sub max} of 2141 {+-} 500 nmol/min/mg and a K {sub m} of 11 {+-} 4 {mu}M. This enzyme was inhibited by pyrazole with a K {sub I} of 3.1 {+-} 0.57 {mu}M. 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 {sub max} of 115 nmol/min/mg and a K {sub m} of 15 {+-} 2 {mu}M and was not inhibited by pyrazole.

  15. Reliability of a flushing questionnaire and the ethanol patch test in screening for inactive aldehyde dehydrogenase-2 and alcohol-related cancer risk.

    PubMed

    Yokoyama, A; Muramatsu, T; Ohmori, T; Kumagai, Y; Higuchi, S; Ishii, H

    1997-12-01

    Molecular epidemiology of esophageal and upper aerodigestive tract cancers revealed that alcohol is more carcinogenic in persons with inactive aldehyde dehydrogenase-2 (ALDH2) than in those with active ALDH2. A simple questionnaire has been developed to screen for the facial flushing that occurs in persons with inactive ALDH2 when they drink even a single glass of beer. In this study, 266 of 284 consecutive male Japanese clinic patients (age > or = 50 years) completed the flushing questionnaire, and 239 underwent the ethanol patch test (a cutaneous model for the flushing response). Blinded genotyping showed inactive ALDH2 for 94.4% (102 of 108) of subjects who reported always flushing (early in their drinking history or currently) and for 47.7% (21 of 44) of those who reported sometimes flushing, whereas 95.6% (109 of 114) of subjects reporting that they never exhibited facial flushing had active ALDH2. When all three categories of flushing (current always, former always, and sometimes) were collapsed into one, the questionnaire's sensitivity and specificity for identifying inactive ALDH2 were 96.1 and 79.0%, respectively, compared with 72.4 and 71.4% for the ethanol patch test. The results suggest the utility of this simple flushing questionnaire in daily practice, as well as large-scale studies to assess cancer risks associated with drinking and ALDH2 and for activities aimed at preventing alcohol-related cancer. PMID:9419411

  16. Two clinical drugs deubiquitinase inhibitor auranofin and aldehyde dehydrogenase inhibitor disulfiram trigger synergistic anti-tumor effects in vitro and in vivo

    PubMed Central

    Liu, Ningning; Hua, Xianliang; Cai, Jianyu; Yang, Changshan; Long, Huidan; Zhao, Chong; Chen, Xin; Lan, Xiaoying; Zang, Dan; Wu, Jinjie; Li, Xiaofen; Shi, Xianping; Wang, Xuejun; Liu, Jinbao

    2016-01-01

    Inhibition of proteasome-associated deubiquitinases (DUBs) is emerging as a novel strategy for cancer therapy. It was recently reported that auranofin (Aur), a gold (I)-containing compound used clinically to treat rheumatoid arthritis, is a proteasome-associated DUB inhibitor. Disulfiram (DSF), an inhibitor of aldehyde dehydrogenase, is currently in clinical use for treating alcoholism. Recent studies have indicated that DSF can also act as an antitumor agent. We investigated the effect of combining DSF and Aur on apoptosis induction and tumor growth in hepatoma cancer cells. Here we report that (i) the combined treatment of Aur and DSF results in synergistic cytotoxicity to hepatoma cells in vitro and in vivo; (ii) Aur and DSF in combination induces caspase activation, endoplasmic reticulum (ER) stress, and reactive oxygen species (ROS) production; (iii) pan-caspase inhibitor z-VAD-FMK could efficiently block apoptosis but not proteasome inhibition induced by Aur and DSF combined treatment, and ROS is not required for Aur+DSF to induce apoptosis. Collectively, we demonstrate a model of synergism between DSF and proteasome-associated DUB inhibitor Aur in the induction of apoptosis in hepatoma cancer cells, identifying a potential novel anticancer strategy for clinical use in the future. PMID:26625200

  17. A proposal for nomenclature of aldehyde dehydrogenases in Saccharomyces cerevisiae and characterization of the stress-inducible ALD2 and ALD3 genes.

    PubMed

    Navarro-Aviño, J P; Prasad, R; Miralles, V J; Benito, R M; Serrano, R

    1999-07-01

    The complete sequencing of the genome of Saccharomyces cerevisiae indicated that this organism contains five genes encoding aldehyde dehydrogenases. YOR374w and YER073w correspond to the mitochondrial isoforms and we propose as gene names ALD4 and ALD5, respectively. YPL061w has been described as the cytoplasmic constitutive isoform and named ALD6. We characterize here the tandem-repeated ORFs YMR170c and YMR169c as the cytoplasmic stress-inducible isoforms, with gene names ALD2 and ALD3, respectively. The expression of ALD2 and ALD3 is dependent on the general-stress transcription factors Msn2,4 but independent of the HOG MAP kinase pathway. ALD3 is induced by a variety of stresses, including osmotic shock, heat shock, glucose exhaustion, oxidative stress and drugs. ALD2 is only induced by osmotic stress and glucose exhaustion. A double null mutant, ald2 ald3, exhibited unchanged sensitivity to any of the above stresses. The only phenotype detected in this mutant was a reduced growth rate in ethanol medium as compared to the wild type. PMID:10407263

  18. Single-dose ethanol administration downregulates expression of cytochrome p450 2E1 mRNA in aldehyde dehydrogenase 2 knockout mice.

    PubMed

    Matsumoto, Akiko; Kawamoto, Toshihiro; Horita, Mikako; Takahashi, Tatsuya; Isse, Toyohi; Oyama, Tsunehiro; Ichiba, Masayoshi

    2007-12-01

    The polymorphism of aldehyde dehydrogenase 2 (ALDH2), denoted ALDH2*2, is very common in East Asian origin. Acetaldehyde, an intermediate metabolite of ethanol, is metabolized very slowly in people with ALDH2*2 because the mutant ALDH2 protein lacks the activity of acetaldehyde metabolism. On the other hand, it is well established that one of the cytochrome P450 enzymes, CYP2E1, is an activator of carcinogens (e.g., nitorosamines) and a generator of oxidative stress, and it is shown that CYP2E1 was induced by ethanol via gene transcriptional regulation. In the present study, to examine the consequences of ALDH2 polymorphism on transcriptional regulation of CYP2E1 in liver tissue, Aldh2+/+ and Aldh2-/- mice were orally administered 5 g/kg body weight of ethanol and the levels of CYP2E1 mRNA in liver tissue then analyzed. The level of CYP2E1 mRNA 12h after the ethanol administration tended to be higher than the 0-h group in Aldh2+/+ mice, however, it was significantly lower than the 0-h group in Aldh2-/- mice. These findings suggest that single-dose ethanol administration downregulates the expression of cytochrome p450 2E1 mRNA in the presence of inactive ALDH2. PMID:17980998

  19. 9-O-acetylated sialic acids differentiating normal haematopoietic precursors from leukemic stem cells with high aldehyde dehydrogenase activity in children with acute lymphoblastic leukaemia.

    PubMed

    Chowdhury, Suchandra; Chandra, Sarmila; Mandal, Chitra

    2014-10-01

    Childhood acute lymphoblastic leukaemia (ALL) originates from mutations in haematopoietic progenitor cells (HPCs). For high-risk patients, treated with intensified post-remission chemotherapy, haematopoietic stem cell (HSC) transplantation is considered. Autologous HSC transplantation needs improvisation till date. Previous studies established enhanced disease-associated expression of 9-O-acetylated sialoglycoproteins (Neu5,9Ac2-GPs) on lymphoblasts of these patients at diagnosis, followed by its decrease with clinical remission and reappearance with relapse. Based on this differential expression of Neu5,9Ac2-GPs, identification of a normal HPC population was targeted from patients at diagnosis. This study identifies two distinct haematopoietic progenitor populations from bone marrow of diagnostic ALL patients, exploring the differential expression of Neu5,9Ac2-GPs with stem cell (CD34, CD90, CD117, CD133), haematopoietic (CD45), lineage-commitment (CD38) antigens and cytosolic aldehyde dehydrogenase (ALDH). Normal haematopoietic progenitor cells (ALDH(+)SSC(lo)CD45(hi)Neu5,9Ac2 -GPs(lo)CD34(+)CD38(-)CD90(+)CD117(+)CD133(+)) differentiated into morphologically different, lineage-specific colonies, being crucial for autologous HSC transplantation while leukemic stem cells (ALDH(+)SSC(lo)CD45(lo)Neu5,9Ac2 -GPs(hi)CD34(+)CD38(+)CD90(-)CD117(-)CD133(-)) lacking this ability can be potential targets for minimal residual disease detection and drug-targeted immunotherapy. PMID:25283637

  20. MUC1-C Oncoprotein Activates ERK→C/EBPβ Signaling and Induction of Aldehyde Dehydrogenase 1A1 in Breast Cancer Cells*

    PubMed Central

    Alam, Maroof; Ahmad, Rehan; Rajabi, Hasan; Kharbanda, Akriti; Kufe, Donald

    2013-01-01

    Aldehyde dehydrogenase 1A1 (ALDH1A1) activity is used as a marker of breast cancer stem cells; however, little is known about the regulation of ALDH1A1 expression. Mucin 1 (MUC1) is a heterodimeric protein that is aberrantly overexpressed in most human breast cancers. In studies of breast cancer cells stably silenced for MUC1 or overexpressing the oncogenic MUC1-C subunit, we demonstrate that MUC1-C is sufficient for induction of MEK→ERK signaling and that treatment with a MUC1-C inhibitor suppresses ERK activation. In turn, MUC1-C induces ERK-mediated phosphorylation and activation of the CCAAT/enhancer-binding protein β (C/EBPβ) transcription factor. The results further show that MUC1-C and C/EBPβ form a complex on the ALDH1A1 gene promoter and activate ALDH1A1 gene transcription. MUC1-C-induced up-regulation of ALDH1A1 expression is associated with increases in ALDH activity and is detectable in stem-like cells when expanded as mammospheres. These findings demonstrate that MUC1-C (i) activates a previously unrecognized ERK→C/EBPβ→ALDH1A1 pathway, and (ii) promotes the induction of ALDH activity in breast cancer cells. PMID:24043631

  1. Pharmacological recruitment of aldehyde dehydrogenase 3A1 (ALDH3A1) to assist ALDH2 in acetaldehyde and ethanol metabolism in vivo

    PubMed Central

    Chen, Che-Hong; Cruz, Leslie A.; Mochly-Rosen, Daria

    2015-01-01

    Correcting a genetic mutation that leads to a loss of function has been a challenge. One such mutation is in aldehyde dehydrogenase 2 (ALDH2), denoted ALDH2*2. This mutation is present in ∼0.6 billion East Asians and results in accumulation of toxic acetaldehyde after consumption of ethanol. To temporarily increase metabolism of acetaldehyde in vivo, we describe an approach in which a pharmacologic agent recruited another ALDH to metabolize acetaldehyde. We focused on ALDH3A1, which is enriched in the upper aerodigestive track, and identified Alda-89 as a small molecule that enables ALDH3A1 to metabolize acetaldehyde. When given together with the ALDH2-specific activator, Alda-1, Alda-89 reduced acetaldehyde-induced behavioral impairment by causing a rapid reduction in blood ethanol and acetaldehyde levels after acute ethanol intoxication in both wild-type and ALDH2-deficient, ALDH2*1/*2, heterozygotic knock-in mice. The use of a pharmacologic agent to recruit an enzyme to metabolize a substrate that it usually does not metabolize may represent a novel means to temporarily increase elimination of toxic agents in vivo. PMID:25713355

  2. Molecular Clone and Expression of a NAD+-Dependent Glycerol-3-Phosphate Dehydrogenase Isozyme Gene from the Halotolerant alga Dunaliella salina

    PubMed Central

    Cai, Ma; He, Li-Hong; Yu, Tu-Yuan

    2013-01-01

    Glycerol is an important osmotically compatible solute in Dunaliella. Glycerol-3-phosphate dehydrogenase (G3PDH) is a key enzyme in the pathway of glycerol synthesis, which converts dihydroxyacetone phosphate (DHAP) to glycerol-3-phosphate. Generally, the glycerol-DHAP cycle pathway, which is driven by G3PDH, is considered as the rate-limiting enzyme to regulate the glycerol level under osmotic shocks. Considering the peculiarity in osmoregulation, the cDNA of a NAD+-dependent G3PDH was isolated from D. salina using RACE and RT-PCR approaches in this study. Results indicated that the length of the cDNA sequence of G3PDH was 2,100 bp encoding a 699 amino acid deduced polypeptide whose computational molecular weight was 76.6 kDa. Conserved domain analysis revealed that the G3PDH protein has two independent functional domains, SerB and G3PDH domains. It was predicted that the G3PDH was a nonsecretory protein and may be located in the chloroplast of D. salina. Phylogenetic analysis demonstrated that the D. salina G3PDH had a closer relationship with the G3PDHs from the Dunaliella genus than with those from other species. In addition, the cDNA was subsequently subcloned in the pET-32a(+) vector and was transformed into E. coli strain BL21 (DE3), a expression protein with 100 kDa was identified, which was consistent with the theoretical value. PMID:23626797

  3. Effects of L-carnitine and Pentoxifylline on the Activity of Lactate Dehydrogenase C4 isozyme and Motility of Testicular Spermatozoa in Mice

    PubMed Central

    Aliabadi, Elham; Karimi, Fatemeh; Rasti, Mozhgan; Akmali, Masoumeh; Esmaeilpour, Tahereh

    2013-01-01

    Background Extracted sperm from the testis have poor motility. Moreover, their motility changes during their journey through epidydimis. Meanwhile, they face high concentration of L-carnitin. In addition, lactate dehydrogenase C4 (LDH-C4) gene disorders has been shown to cause impaired sperm motility, leading to infertility in male mice. The aim of this study was to evaluate sperm motility and LDH-C4 enzyme activity upon L-carnitine (LC) and Pentoxifylline (PTX) administrations in mice. Methods We extracted testicular sperm of 48 mice and divided them into three equal parts. One part was incubated with Ham's F10 medium (control), the other parts were treated with Ham's F10 containing LC and PTX with a final concentration of 1.76 mM, for 30 min at room temperature. Sperm motility was assessed according to the World Health Organization (WHO) criteria. Sperm LDH-C4 enzyme activity was measured by spectrophotometery method. Statistical analyses were performed using ANOVA and Fisher's LSD test, and a p-value less than 0.05 was considered as a statistically significant difference. Results Sperm motility increased after 30 min of incubation in LC- and PTX-treated group (p<0.001). LC and PTX administrations showed a significant increase in the LDHC4 enzyme activity of sperm compared to that of the controls after 30 min (P=0.04 and 0.01, respectively). Conclusion The effects of LC and PTX on motility of sperm can be explained by an increase in LDH-C4 enzyme activity that may influence male fertility status. We suggest that LC as a non-toxic antioxidant is more suitable for use in assisted reproductive technique protocols than PTX. PMID:23926565

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

    Zheng, Tianyong; Olson, Daniel G.; Tian, Liang; Bomble, Yannick J.; Himmel, Michael E.; Lo, Jonathan; Hon, Shuen; Shaw, A. Joe; van Dijken, Johannes P.

    2015-01-01

    ABSTRACT 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 the theoretical maximum, engineered strains of C. thermocellum produce ethanol at lower yields (∼50% of the theoretical maximum). In the course of engineering these strains, a number of mutations have been discovered in their adhE genes, which encode both alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) enzymes. To understand the effects of these mutations, the adhE genes from six strains of C. thermocellum and T. saccharolyticum were cloned and expressed in Escherichia coli, the enzymes produced were purified by affinity chromatography, and enzyme activity was measured. In wild-type strains of both organisms, NADH was the preferred cofactor for both ALDH and ADH activities. In high-ethanol-producing (ethanologen) strains of T. saccharolyticum, both ALDH and ADH activities showed increased NADPH-linked activity. Interestingly, the AdhE protein of the ethanologenic strain of C. thermocellum has acquired high NADPH-linked ADH activity while maintaining NADH-linked ALDH and ADH activities at wild-type levels. When single amino acid mutations in AdhE that caused increased NADPH-linked ADH activity were introduced into C. thermocellum and T. saccharolyticum, ethanol production increased in both organisms. Structural analysis of the wild-type and mutant AdhE proteins was performed to provide explanations for the cofactor specificity change on a molecular level. IMPORTANCE This work describes the characterization of the AdhE enzyme from different strains of C. thermocellum and T. saccharolyticum. C. thermocellum and T. saccharolyticum are thermophilic anaerobes that have been engineered to make high yields of ethanol and can solubilize components of

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

    PubMed

    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. PMID:24824603

  8. Strong Protective Effect of The Aldehyde Dehydrogenase Gene (ALDH2) 504lys (*2) Allele Against Alcoholism And Alcohol-Induced Medical Diseases in Asians

    PubMed Central

    Li, Dawei; Zhao, Hongyu; Gelernter, Joel

    2013-01-01

    Alcohol is oxidized to acetaldehyde, which in turn is oxidized to acetate. The aldehyde dehydrogenase 2 gene (ALDH2) is the most important gene responsible for acetaldehyde metabolism. Individuals heterozygous or homozygous for the lys (A or *2) allele at the single nucleotide polymorphism (SNP) glu504lys (rs671) of ALDH2 have greatly reduced ability to metabolize acetaldehyde, which greatly decreases their risk for alcohol dependence (AD). Case-control studies have shown association between this SNP and alcohol dependence as well as alcohol-induced liver disease. However, some studies have produced insignificant results. Using cumulative data from the past 20 years predominately from Asian populations (from both English and Chinese publications), this meta-analysis sought to examine and update whether the aggregate data provide new evidence of statistical significance for the proposed association. Our results (9,678 cases and 7,331 controls from 53 studies) support a strong association of alcohol abuse and dependence, with allelic P value of 3×10−56 and OR of 0.23 (0.2, 0.28) under the random effects model. The dominant model (lys-lys + lys-glu vs. glu-glu) also showed strong association with P value of 1×10−44 and OR of 0.22 (0.18, 0.27). When stricter criteria and various sub-group analyses were applied, the association remained strong (for example, OR = 0.23 (0.18, 0.3) and P = 2×10−28 for the alcoholic patients with alcoholic liver disease, cirrhosis, or pancreatitis). These findings provide confirmation of the involvement of the human ALDH2 gene in the pathogenesis of AD as well as alcohol-induced medical illnesses in East-Asians. PMID:22102315

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

    PubMed

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

    2016-01-22

    Cancer stem cells (CSCs), known as tumor initiating cells, have become a critically important issue for cancer therapy. Although much research has demonstrated the induction of hepato cellular carcinoma by aflatoxin B1, the formation of hepatocellular CSCs and their quantitative determination is hardly reported. In this work, it was found that hepatocellular CSCs were produced from HepG2 cells by aflatoxin B1-induced mutation, and their amount was quantitatively determined using crosstalk-eliminated multicolor cellular imaging based on quantum dot (Qdot) nanoprobes and an acousto-optical tunable filter (AOTF). Hepatocellular CSCs were acquired via magnetic bead-based sorting and observed using concurrent detection of three different markers: CD133, CD44, and aldehyde dehydrogenase1 (ALDH1). The DNA mutation of HepG2 cells caused by aflatoxin B1 was quantitatively observed via absorbance spectra of aflatoxin B1-8, 9-epoxide-DNA adducts. The percentages of hepatocellular CSCs formed in the entire HepG2 cells were determined to be 9.77±0.65%, 10.9±1.39%, 11.4±1.32%, and 12.8±0.7%, respectively, at 0 μM, 5 μM, 10 μM, and 20 μM of aflatoxin B1. The results matched well with those obtained utilizing flow cytometry. This study demonstrates that aflatoxin mediated mutation induced the conversion of hepatic cancer cell to hepatic CSCs by using a Qdot based constructed multicolor cellular imaging system. PMID:26739636

  10. Aldehyde-alcohol dehydrogenase and/or thiolase overexpression coupled with CoA transferase downregulation lead to higher alcohol titers and selectivity in Clostridium acetobutylicum fermentations.

    PubMed

    Sillers, Ryan; Al-Hinai, Mohab Ali; Papoutsakis, Eleftherios T

    2009-01-01

    Metabolic engineering (ME) of Clostridium acetobutylicum has led to increased solvent (butanol, acetone, and ethanol) production and solvent tolerance, thus demonstrating that further efforts have the potential to create strains of industrial importance. With recently developed ME tools, it is now possible to combine genetic modifications and thus implement more advanced ME strategies. We have previously shown that antisense RNA (asRNA)-based downregulation of CoA transferase (CoAT, the first enzyme in the acetone-formation pathway) results in increased butanol to acetone selectivity, but overall reduced butanol yields and titers. In this study the alcohol/aldehyde dehydrogenase (aad) gene (encoding the bifunctional protein AAD responsible for butanol and ethanol production from butyryl-CoA and acetyl-CoA, respectively) was expressed from the phosphotransbutyrylase (ptb) promoter to enhance butanol formation and selectivity, while CoAT downregulation was used to minimize acetone production. This led to early production of high alcohol (butanol plus ethanol) titers, overall solvent titers of 30 g/L, and a higher alcohol/acetone ratio. Metabolic flux analysis revealed the likely depletion of butyryl-CoA. In order to increase then the flux towards butyryl-CoA, we examined the impact of thiolase (THL, thl) overexpression. THL converts acetyl-CoA to acetoacetyl-CoA, the first step of the pathway from acetyl-CoA to butyryl-CoA, and thus, combining thl overexpression with aad overexpression decreased, as expected, acetate and ethanol production while increasing acetone and butyrate formation. thl overexpression in strains with asRNA CoAT downregulation did not significantly alter product formation thus suggesting that a more complex metabolic engineering strategy is necessary to enhance the intracellular butyryl-CoA pool and reduce the acetyl-CoA pool in order to achieve improved butanol titers and selectivity. PMID:18726959

  11. Structural and Functional Consequences of Coenzyme Binding to the Inactive Asian Variant of Mitochondrial Aldehyde Dehydrogenase: Roles of Residues 475 and 487

    SciTech Connect

    Larson,H.; Zhou, J.; Chen, Z.; Stamler, J.; Weiner, H.; Hurley, T.

    2007-01-01

    The common mitochondrial aldehyde dehydrogenase (ALDH2) ALDH2*2 polymorphism is associated with impaired ethanol metabolism and decreased efficacy of nitroglycerin treatment. These physiological effects are due to the substitution of Lys for Glu-487 that reduces the k{sub cat} for these processes and increases the K{sub m} for NAD{sup +}, as compared with ALDH2. In this study, we sought to understand the nature of the interactions that give rise to the loss of structural integrity and low activity in ALDH2*2 even when complexed with coenzyme. Consequently, we have solved the crystal structure of ALDH2*2 complexed with coenzyme to 2.5 {angstrom}. We have also solved the structures of a mutated form of ALDH2 where Arg-475 is replaced by Gln (R475Q). The structural and functional properties of the R475Q enzyme are intermediate between those of wild-type and the ALDH2*2 enzymes. In both cases, the binding of coenzyme restores most of the structural deficits observed in the apoenzyme structures. The binding of coenzyme to the R475Q enzyme restores its structure and catalytic properties to near wild-type levels. In contrast, the disordered helix within the coenzyme binding pocket of ALDH2*2 is reordered, but the active site is only partially reordered. Consistent with the structural data, ALDH2*2 showed a concentration-dependent increase in esterase activity and nitroglycerin reductase activity upon addition of coenzyme, but the levels of activity do not approach those of the wild-type enzyme or that of the R475Q enzyme. The data presented shows that Glu-487 maintains a critical function in linking the structure of the coenzyme binding site to that of the active site through its interactions with Arg-264 and Arg-475, and in doing so, creates the stable structural scaffold conducive to catalysis.

  12. Aberrant expression of aldehyde dehydrogenase 1A (ALDH1A) subfamily genes in acute lymphoblastic leukaemia is a common feature of T-lineage tumours.

    PubMed

    Longville, Brooke A C; Anderson, Denise; Welch, Mathew D; Kees, Ursula R; Greene, Wayne K

    2015-01-01

    The class 1A aldehyde dehydrogenase (ALDH1A) subfamily of genes encode enzymes that function at the apex of the retinoic acid (RA) signalling pathway. We detected aberrant expression of ALDH1A genes, particularly ALDH1A2, in a majority (72%) of primary paediatric T cell acute lymphoblastic leukaemia (T-ALL) specimens. ALDH1A expression was almost exclusive to T-lineage, but not B-lineage, ALL. To determine whether ALDH1A expression may have relevance to T-ALL cell growth and survival, the effect of inhibiting ALDH1A function was measured on a panel of human ALL cell lines. This revealed that T-ALL proliferation had a higher sensitivity to modulation of ALDH1A activity and RA signalling as compared to ALL cell lines of B-lineage. Consistent with these findings, the genes most highly correlated with ALDH1A2 expression were involved in cell proliferation and apoptosis. Evidence that such genes may be targets of regulation via RA signalling initiated by ALDH1A activity was provided by the TNFRSF10B gene, encoding the apoptotic death receptor TNFRSF10B (also termed TRAIL-R2), which negatively correlated with ALDH1A2 and showed elevated transcription following treatment of T-ALL cell lines with the ALDH1A inhibitor citral (3,7-dimethyl-2,6-octadienal). These data indicate that ALDH1A expression is a common event in T-ALL and supports a role for these enzymes in the pathobiology of this disease. PMID:25208926

  13. Impact of smoking on lung cancer risk is stronger in those with the homozygous aldehyde dehydrogenase 2 null allele in a Japanese population.

    PubMed

    Park, Ji Young; Matsuo, Keitaro; Suzuki, Takeshi; Ito, Hidemi; Hosono, Satoyo; Kawase, Takakazu; Watanabe, Miki; Oze, Isao; Hida, Toyoaki; Yatabe, Yasushi; Mitsudomi, Tetsuya; Takezaki, Toshiro; Tajima, Kazuo; Tanaka, Hideo

    2010-04-01

    The main lifestyle contributor to acetaldehyde exposure is the drinking of alcoholic beverages, but tobacco smoke also makes some contribution. Although acetaldehyde is associated with upper aerodigestive tract cancer risk, in accordance with genetically determined acetaldehyde metabolism, it is unclear whether lung cancer, a representative smoking-related cancer, is associated with acetaldehyde or genes impacting its metabolism. We conducted a case-control study to examine possible interaction between smoking and aldehyde dehydrogenase 2 (ALDH2) Glu504Lys polymorphism (rs671) on the risk of lung cancer in Japanese. Subjects were 718 lung cancer cases and 1416 non-cancer controls enrolled in the Hospital-based Epidemiologic Research Program at Aichi Cancer Center. Lifestyle factors, including smoking, were determined by self-administered questionnaire. We applied pack-years (PY; categorized into five levels: never, <15, <30, <45 and > or =45) as a marker of cumulative exposure to smoking. The impact of smoking, ALDH2 genotype, and their interaction on lung cancer risk were assessed by odds ratio (OR) and 95% confidence interval adjusted for potential confounders. Adjusted ORs for PY <15, <30, <45 and > or =45 relative to never smokers among those with Glu/Glu or Glu/Lys were 1.39, 1.80, 3.44 and 6.25, respectively (P-trend = 1.4 x 10(-30)). In contrast, ORs among Lys/Lys were 1.01, 10.2, 11.4 and 23.2, respectively (P-trend = 2.6 x 10(-7)). Interaction between ALDH2 genotype (Glu/Glu + Glu/Lys versus Lys/Lys) and cumulative smoking dose was statistically significant (P = 0.036) and was consistently observed in the analysis among never-drinkers (interaction P = 0.041). These results suggest that ALDH2 Lys/Lys, a null enzyme activity genotype, modifies the impact of smoking on the risk of lung cancer. PMID:20093384

  14. Association between Carotid Intima-media Thickness and Aldehyde Dehydrogenase 2 Glu504Lys Polymorphism in Chinese Han with Essential Hypertension

    PubMed Central

    Ma, Xiao-Xiang; Zheng, Shu-Zhan; Shu, Yan; Wang, Yong; Chen, Xiao-Ping

    2016-01-01

    Background: Aldehyde dehydrogenase 2 (ALDH2) is involved in the pathophysiological processes of cardiovascular diseases. Recent studies showed that mutant ALDH2 could increase oxidative stress and is a susceptible factor for hypertension. In addition, wild-type ALDH2 could improve the endothelial functions, therefore reducing the risk of developing atherosclerosis. The aim of the present study was to explore the frequency of the Glu504Lys polymorphism of the ALDH2 gene and its relation to carotid intima-media thickness (CIMT) in a group of patients with essential hypertension (EH) and to investigate the association between the Glu504Lys polymorphism and CIMT in Chinese Han patients with EH. Methods: In this study, 410 Chinese Han patients with EH who received physical examinations at the People's Hospital of Sichuan Province (China) were selected. DNA microarray chip was used for the genotyping of the Glu504Lys polymorphism of the ALDH2 gene. The differences in CIMT among patients with different Glu504Lys ALDH2 genotypes were analyzed. Results: The mean CIMT of the patients carrying AA/AG and GG genotypes was 1.02 ± 0.31 mm and 0.78 ± 0.28 mm, respectively. One-way ANOVA showed that the CIMT of the patients carrying the AA/AG genotype was significantly higher than in the ones carrying the GG genotype (P < 0.001). Multivariate logistic regression showed that the Glu504Lys AA/AG genotype of the ALDH2 gene was one of the major factors influencing the CIMT in patients with EH (odds ratio = 3.731, 95% confidence interval = 1.589–8.124, P = 0.001). Conclusions: The Glu504Lys polymorphism of the ALDH2 gene is associated with the CIMT of Chinese Han patients with EH in Sichuan, China. PMID:27270535

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2014-04-01

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

  17. Extended flow cytometry characterization of normal bone marrow progenitor cells by simultaneous detection of aldehyde dehydrogenase and early hematopoietic antigens: implication for erythroid differentiation studies

    PubMed Central

    Mirabelli, Peppino; Di Noto, Rosa; Lo Pardo, Catia; Morabito, Paolo; Abate, Giovanna; Gorrese, Marisa; Raia, Maddalena; Pascariello, Caterina; Scalia, Giulia; Gemei, Marica; Mariotti, Elisabetta; Del Vecchio, Luigi

    2008-01-01

    Background Aldehyde dehydrogenase (ALDH) is a cytosolic enzyme highly expressed in hematopoietic precursors from cord blood and granulocyte-colony stimulating factor mobilized peripheral blood, as well as in bone marrow from patients with acute myeloblastic leukemia. As regards human normal bone marrow, detailed characterization of ALDH+ cells has been addressed by one single study (Gentry et al, 2007). The goal of our work was to provide new information about the dissection of normal bone marrow progenitor cells based upon the simultaneous detection by flow cytometry of ALDH and early hematopoietic antigens, with particular attention to the expression of ALDH on erythroid precursors. To this aim, we used three kinds of approach: i) multidimensional analytical flow cytometry, detecting ALDH and early hematopoietic antigens in normal bone marrow; ii) fluorescence activated cell sorting of distinct subpopulations of progenitor cells, followed by in vitro induction of erythroid differentiation; iii) detection of ALDH+ cellular subsets in bone marrow from pure red cell aplasia patients. Results In normal bone marrow, we identified three populations of cells, namely ALDH+CD34+, ALDH-CD34+ and ALDH+CD34- (median percentages were 0.52, 0.53 and 0.57, respectively). As compared to ALDH-CD34+ cells, ALDH+CD34+ cells expressed the phenotypic profile of primitive hematopoietic progenitor cells, with brighter expression of CD117 and CD133, accompanied by lower display of CD38 and CD45RA. Of interest, ALDH+CD34- population disclosed a straightforward erythroid commitment, on the basis of three orders of evidences. First of all, ALDH+CD34- cells showed a CD71bright, CD105+, CD45- phenotype. Secondly, induction of differentiation experiments evidenced a clear-cut expression of glycophorin A (CD235a). Finally, ALDH+CD34- precursors were not detectable in patients with pure red cell aplasia (PRCA). Conclusion Our study, comparing surface antigen expression of ALDH+/CD34+, ALDH

  18. ALDH isozymes downregulation affects cell growth, cell motility and gene expression in lung cancer cells

    PubMed Central

    Moreb, Jan S; Baker, Henry V; Chang, Lung-Ji; Amaya, Maria; Lopez, M Cecilia; Ostmark, Blanca; Chou, Wayne

    2008-01-01

    Background Aldehyde dehydrogenase isozymes ALDH1A1 and ALDH3A1 are highly expressed in non small cell lung cancer. Neither the mechanisms nor the biologic significance for such over expression have been studied. Methods We have employed oligonucleotide microarrays to analyze changes in gene profiles in A549 lung cancer cell line in which ALDH activity was reduced by up to 95% using lentiviral mediated expression of siRNA against both isozymes (Lenti 1+3). Stringent analysis methods were used to identify gene expression patterns that are specific to the knock down of ALDH activity and significantly different in comparison to wild type A549 cells (WT) or cells similarly transduced with green fluorescent protein (GFP) siRNA. Results We confirmed significant and specific down regulation of ALDH1A1 and ALDH3A1 in Lenti 1+3 cells and in comparison to 12 other ALDH genes detected. The results of the microarray analysis were validated by real time RT-PCR on RNA obtained from Lenti 1+3 or WT cells treated with ALDH activity inhibitors. Detailed functional analysis was performed on 101 genes that were significantly different (P < 0.001) and their expression changed by ≥ 2 folds in the Lenti 1+3 group versus the control groups. There were 75 down regulated and 26 up regulated genes. Protein binding, organ development, signal transduction, transcription, lipid metabolism, and cell migration and adhesion were among the most affected pathways. Conclusion These molecular effects of the ALDH knock-down are associated with in vitro functional changes in the proliferation and motility of these cells and demonstrate the significance of ALDH enzymes in cell homeostasis with a potentially significant impact on the treatment of lung cancer. PMID:19025616

  19. Tryptophan in Alcoholism Treatment II:  Inhibition of the Rat Liver Mitochondrial Low Km Aldehyde Dehydrogenase Activity, Elevation of Blood Acetaldehyde Concentration and Induction of Aversion to Alcohol by Combined Administration of Tryptophan and Benserazide

    PubMed Central

    Badawy, Abdulla A.-B.; Bano, Samina; Steptoe, Alex

    2011-01-01

    Aims: The aims were to provide proofs of mechanism and principle by establishing the ability of the amino acid L-tryptophan (Trp) combined with the kynureninase inhibitor benserazide (BSZ) to inhibit the liver mitochondrial low Km aldehyde dehydrogenase (ALDH) activity after administration and in vivo and to induce aversion to alcohol. Methods: Trp, BSZ or both were administered to male Wistar rats and ALDH activity was determined both in vitro in liver homogenates and in vivo (by measuring acetaldehyde accumulation in blood after ethanol administration). Alcohol consumption was studied in an aversion model in rats and in alcohol-preferring C57 mice. Results: Combined administration of Trp + BSZ, but neither compound alone, produced a strong inhibition of ALDH activity and an increase in blood acetaldehyde concentration after ethanol, and induced aversion to alcohol in rats and decreased preference in mice. Another kynureninase inhibitor, carbidopa, induced aversion to alcohol by itself, which was reversed by Trp co-administration. Conclusions: The present results establish a prior art for the use of a combination of Trp plus BSZ in the treatment of alcoholism by aversion, which merits rapid clinical development. PMID:21896551

  20. Synergetic bitherapy in mice with xenografts of human prostate cancer using a methional mimic (METLICO) and an aldehyde dehydrogenase 3 inhibitor (MATE): systemic intraperitoneal (IP) and targeted intra-tumoral (IT) administration.

    PubMed

    Hiltbrand, E; Fournet, G; Giliberto, J-P; Paret, M-J; Chantepie, J; Morel, D; Goré, J; Reichert, U; Mehier, H; Rochedix, M-E; Quash, G

    2009-01-01

    An intraperitoneal (IP) monotherapy in nu/nu mice with subcutaneous xenografts of a human prostate epithelial cancer cell line:DU145 was undertaken with an aldehyde dehydrogenase 3 inhibitor MATE, that is a potent apoptogen on (DU145) in culture but not on their human prostate epithelial normal counterparts [13] . Tumour growth was slowed down but treatment had to be done 5days/week. To try to potentiate the action of MATE in vivo, a bitherapy was undertaken based on the synergetic apoptotic effect that had been observed previously in culture on DU145 treated with a methional mimic METLICO and DIMATE, an inhibitor of ALDH1 and ALDH3 [19]. The bitherapy with METLICO/MATE administered IP was as effective as the monotherapy with MATE alone by IP, but at a 2-fold lower dose of MATE and at a dose of METLICO that had no growth-inhibitory effect as a monotherapy . Hence there was definite synergism with bitherapy. To try to increase the efficacy of bitherapy, it was administered by the intra-tumoral (IT) route using the recently developed 20-bars-pressurized microinjection system from CERMA [16, 17]. IT administration of the bitherapy was indeed more effective than that by IP as regards tumour volumes are concerned. Histopathological analysis of IT-treated tumours confirmed that there were many necrotized zones but intact cells were still present. Approaches for treating a wider zone of tumour tissue by IT-bitherapy are discussed. PMID:19355878

  1. Distinguishing clonal apple rootstocks by isozymes banding patterns.

    PubMed

    Kaushal, K; Modgil, M; Sharma, D R

    2001-11-01

    Molecular characterisation of clonal apple rootstocks using isozymes was carried out to identify isozyme polymorphism in seven clonal apple rootstocks and to identify the most characteristic and stable enzyme markers for each individual rootstock. Five enzyme systems were studied out of which polyphenol oxidase, malate dehydrogenase, acid phosphatase and peroxidase were useful in discriminating among the rootstocks. The peroxidase enzyme system showed maximum variation and esterase showed the least variation among the rootstocks. Out of seven rootstocks, three were distinguished on the basis of one enzyme system only (M.3 with MDH or PER, M.7 with PPO or PER and MM. 111 with MDH). Out of the sixteen loci studied seven were found to be polymorphic. Genetic variation among the rootstocks was explained on the basis of various parameters. The percentage of polymorphic loci varied from 13.33 to 35.71 per cent. PMID:11906109

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

    PubMed

    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. PMID:19441727

  3. Gene Expression Profiling of NF1-Associated and Sporadic Pilocytic Astrocytoma Identifies Aldehyde Dehydrogenase 1 Family, Member L1 (ALDH1L1) as an Underexpressed Candidate Biomarker in Aggressive Subtypes

    PubMed Central

    Rodriguez, Fausto J.; Giannini, Caterina; Asmann, Yan W.; Sharma, Mukesh K.; Perry, Arie; Tibbetts, Kathleen M.; Jenkins, Robert B.; Scheithauer, Bernd W.; Anant, Shrikant; Jenkins, Sarah; Eberhart, Charles G.; Sarkaria, Jann N.; Gutmann, David H.

    2009-01-01

    Pilocytic astrocytomas (PAs) are WHO grade I gliomas; they most often affect children and young adults and occur in patients with neurofibromatosis type 1 (NF-1). To identify genes that are differentially expressed in sporadic (S-PA) versus NF-1-associated PAs (NF1-PAs) and those that might reflect differences in clinical behavior, we performed gene expression profiling using Affymetrix U133 Plus2.0 GeneChip arrays in 36 S-PAs and 11 NF1-PAs. Thirteen genes were over-expressed and another 13 genes were under-expressed in NF1-associated PAs relative to S-PAs. Immunohistochemical studies performed on 103 tumors, representing 2 independently generated tissue microarrays, confirmed the differential expression of CUGBP2 (p = 0.0014), RANBP9 (p = 0.0075), ITGAV1 (p = 0.0001), and INFGR1 (p = 0.024) proteins. One of the underexpressed genes, aldehyde dehydrogenase 1 family, member L1 (ALDH1L1), was also reduced in clinically aggressive compared to typical PAs (p = 0.01) and in PAs with increased cellularity and necrosis. Furthermore, in an additional independent set of tumors, weak to absent ALDH1L1 expression was found in 13/18 (72%) clinically aggressive PAs, in 8/9 (89%) PAs with pilomyxoid features, in 7/10 (70%) PAs with anaplastic transformation and in 16/21 (76%) diffusely infiltrating astrocytomas of various grades. In summary, we have identified a molecular signature that distinguishes NF1-PA from S-PA, and found that ALDH1L1 underexpression is associated with aggressive histology and/or biological behavior. PMID:19018242

  4. Aldehyde dehydrogenase inhibitors: alpha,beta-acetylenic N-substituted aminothiolesters are reversible growth inhibitors of normal epithelial but irreversible apoptogens for cancer epithelial cells from human prostate in culture.

    PubMed

    Quash, Gerard; Fournet, Guy; Courvoisier, Charlotte; Martinez, Rosa M; Chantepie, Jacqueline; Paret, Marie Julie; Pharaboz, Julie; Joly-Pharaboz, Marie Odile; Goré, Jacques; André, Jean; Reichert, Uwe

    2008-05-01

    The pharmacomodulation of the N atom of alpha,beta-acetylenic aminothiolesters or the replacement of the thiolester moiety by more electrophilic groups did not permit any clear rationale to be established for improving the selective growth-inhibitory activity of this family of compounds over that of the previously synthesized alpha,beta-acetylenic aminothiolesters DIMATE and MATE [G. Quash, G. Fournet, J. Chantepie, J. Goré, C. Ardiet, D. Ardail, Y. Michal, U. Reichert, Biochem Pharmacol 64 (2002) 1279-92]. Hence DIMATE and MATE were investigated more thoroughly for selectivity and growth-inhibitory activity using human prostate epithelial normal cells (HPENC) on the one hand and human prostate epithelial cancer cells (DU145) on the other. Unequivocal evidence was obtained showing that both compounds were reversible growth inhibitors of HPENC but irreversible growth inhibitors of DU145. Growth-inhibition of DU145 was due to the induction of early apoptosis as revealed by the flow cytometric analytical profile of inhibitor-treated cells, of the decrease in the redox potential and increase in superoxide anion content of their mitochondria. Of the two intracellular enzymes: aldehyde dehydrogenases 1 and 3 (ALDH1 and ALDH3) targeted by DIMATE and MATE, ALDH3 was inhibited to the same extent by both compounds whereas ALDH1 was less susceptible to inhibition by MATE. As the induction of ALDH3 by xenobiotics is hormone-dependent, MATE, the more selective of the two inhibitors, is a useful tool not only for examining the role of the ALDH3 isoform in hormone-sensitive and resistant prostate cancer cells in culture but also for investigating if it can inhibit the growth of xenografts of prostate cancer in immunodeficient mice. PMID:17692435

  5. Biochemical Analysis of Recombinant AlkJ from Pseudomonas putida Reveals a Membrane-Associated, Flavin Adenine Dinucleotide-Dependent Dehydrogenase Suitable for the Biosynthetic Production of Aliphatic Aldehydes

    PubMed Central

    Kirmair, Ludwig

    2014-01-01

    The noncanonical alcohol dehydrogenase AlkJ is encoded on the alkane-metabolizing alk operon of the mesophilic bacterium Pseudomonas putida GPo1. To gain insight into the enzymology of AlkJ, we have produced the recombinant protein in Escherichia coli and purified it to homogeneity using His6 tag affinity and size exclusion chromatography (SEC). Despite synthesis in the cytoplasm, AlkJ was associated with the bacterial cell membrane, and solubilization with n-dodecyl-β-d-maltoside was necessary to liberate the enzyme. SEC and spectrophotometric analysis revealed a dimeric quaternary structure with stoichiometrically bound reduced flavin adenine dinucleotide (FADH2). The holoenzyme showed thermal denaturation at moderate temperatures around 35°C, according to both activity assay and temperature-dependent circular dichroism spectroscopy. The tightly bound coenzyme was released only upon denaturation with SDS or treatment with urea-KBr and, after air oxidation, exhibited the characteristic absorption spectrum of FAD. The enzymatic activity of purified AlkJ for 1-butanol, 1-hexanol, and 1-octanol as well as the n-alkanol derivative ω-hydroxy lauric acid methyl ester (HLAMe) was quantified in the presence of the artificial electron acceptors phenazine methosulfate (PMS) and 2,6-dichlorophenolindophenol (DCPIP), indicating broad substrate specificity with the lowest activity on the shortest alcohol, 1-butanol. Furthermore, AlkJ was able to accept as cosubstrates/oxidants the ubiquinone derivatives Q0 and Q1, also in conjunction with cytochrome c, which suggests coupling to the bacterial respiratory chain of this membrane-associated enzyme in its physiological environment. Using gas chromatographic analysis, we demonstrated specific biocatalytic conversion by AlkJ of the substrate HLAMe to the industrially relevant aldehyde, thus enabling the biotechnological production of 12-amino lauric acid methyl ester via subsequent enzymatic transamination. PMID:24509930

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

    EPA Science Inventory

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

  7. The Crystal Structure of a Ternary Complex of Betaine Aldehyde Dehydrogenase from Pseudomonas aeruginosa Provides New Insight Into the Reaction Mechansim and Shows A Novel Binding Mode of the 2'-Phosphate of NADP+ and A Novel Cation Binding Site

    SciTech Connect

    Gonzalez-Segura, L.; Rudino-Pinera, E; Munoz-Clares, R; Horjales, E

    2009-01-01

    In the human pathogen Pseudomonas aeruginosa, the NAD(P)+-dependent betaine aldehyde dehydrogenase (PaBADH) may play the dual role of assimilating carbon and nitrogen from choline or choline precursors-abundant at infection sites-and producing glycine betaine and NADPH, potentially protective against the high-osmolarity and oxidative stresses prevalent in the infected tissues. Disruption of the PaBADH gene negatively affects the growth of bacteria, suggesting that this enzyme could be a target for antibiotic design. PaBADH is one of the few ALDHs that efficiently use NADP+ and one of the even fewer that require K+ ions for stability. Crystals of PaBADH were obtained under aerobic conditions in the presence of 2-mercaptoethanol, glycerol, NADP+ and K+ ions. The three-dimensional structure was determined at 2.1-A resolution. The catalytic cysteine (C286, corresponding to C302 of ALDH2) is oxidized to sulfenic acid or forms a mixed disulfide with 2-mercaptoethanol. The glutamyl residue involved in the deacylation step (E252, corresponding to E268 of ALDH2) is in two conformations, suggesting a proton relay system formed by two well-conserved residues (E464 and K162, corresponding to E476 and K178, respectively, of ALDH2) that connects E252 with the bulk water. In some active sites, a bound glycerol molecule mimics the thiohemiacetal intermediate; its hydroxyl oxygen is hydrogen bonded to the nitrogen of the amide groups of the side chain of the conserved N153 (N169 of ALDH2) and those of the main chain of C286, which form the 'oxyanion hole.' The nicotinamide moiety of the nucleotide is not observed in the crystal, and the adenine moiety binds in the usual way. A salt bridge between E179 (E195 of ALDH2) and R40 (E53 of ALDH2) moves the carboxylate group of the former away from the 2?-phosphate of the NADP+, thus avoiding steric clashes and/or electrostatic repulsion between the two groups. Finally, the crystal shows two K+ binding sites per subunit. One is in an

  8. Aldehyde dehydrogenase and ATP binding cassette transporter G2 (ABCG2) functional assays isolate different populations of prostate stem cells where ABCG2 function selects for cells with increased stem cell activity

    PubMed Central

    2013-01-01

    Introduction High expression of aldehyde dehydrogenase1A1 (ALDH1A1) is observed in many organs and tumors and may identify benign and cancer stem cell populations. Methods In the current study, the stem cell characteristics were determined in cells isolated from human prostate cell lines and clinical prostate specimens based upon the ALDEFLUOR™ assay. Cells isolated based on the ALDEFLUOR™ assay were compared to cells isolated based on ATP binding cassette transporter G2 (ABCG2) activity using the side population assay. To test for stem cell characteristics of self-renewal and multipotency, cells with high and low ALDH1A1 activity, based on the ALDEFLUOR™ assay (ALDHHi and ALDHLow), were isolated from prostate clinical specimens and were recombined with rat urogenital sinus mesenchyme to induce prostate gland formation. Results The percentage of ALDHHi cells in prostate cell lines (RWPE-1, RWPE-2, CWR-R1, and DU-145) was 0.5 to 6%, similarly in non-tumor and tumor clinical specimens the percentage of ALDHHi cells was 0.6 to 4%. Recombinants using ALDHHi cells serially generated prostate tissue up to three generations with as few as 250 starting cells. Immunohistochemical analysis of the recombinants using ALDHHi cells contained prostatic glands frequently expressing androgen receptor (AR), p63, chromogranin A, ALDH1A1, ABCG2, and prostate specific antigen (PSA), compared to their ALDHLow counterparts. Inhibition of ALDH resulted in the reduction of sphere formation capabilities in the CWR-R1, but not in the RWPE-2 and DU-145, prostate cell lines. ABCG2 inhibition resulted in a more robust decrease of sphere formation in androgen sensitive cell lines, CWR-R1 and RWPE-2, but not androgen insensitive DU-145. ALDH1A1 expression was enriched in ALDHHi cells and non-side population cells. ABCG2 expression was only enriched in side population cells. Conclusions The percentage of ALDHHi cells in prostate cell lines and prostate tissue was consistently higher compared

  9. On the distribution and characteristics of isozyme expression in Mycoplasma, Acholeplasma, and Ureaplasma species.

    PubMed Central

    O'Brien, S. J.; Simonson, J. M.; Razin, S.; Barile, M. F.

    1983-01-01

    A summary of a survey of three genera of mycoplasmatales (Mycoplasma, Acholeplasma, and Ureaplasma) for isozyme expression is presented. Isozyme analysis of mycoplasmas has been employed in at least three distinct areas: (1) as genetic markers for identification, individualization, and taxonomic classification; (2) as markers for cell culture contamination; and (3) as a qualitative measure of the operative metabolic pathways in the diverse species. We have found five ubiquitous enzymes: purine nucleoside phosphorylase, adenylate kinase, inorganic pyrophosphatase, dipeptidase, and esterase. Three enzymes, glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, and superoxide dismutase, were restricted to Acholeplasma species and were not detected in Mycoplasma or Ureaplasma. Four glycolytic enzymes, glucose phosphate isomerase, triose phosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase, and lactate dehydrogenase, were restricted to those species of Mycoplasma and Acholeplasma capable of glucose fermentation. Two of these glycolytic enzymes, glucose phosphate isomerase and lactate dehydrogenase, were detected in serovars I and II of U. urealyticum, which is inconsistent with the non-glycolytic activity in this genus. Images FIG. 1 FIG. 2 FIG. 3 PMID:6679151

  10. New Ideas for an Old Enzyme: A Short, Question-Based Laboratory Project for the Purification and Identification of an Unknown LDH Isozyme

    ERIC Educational Resources Information Center

    Coleman, Aaron B.

    2010-01-01

    Enzyme purification projects are an excellent way to introduce many aspects of protein biochemistry, but can be difficult to carry out under the constraints of a typical undergraduate laboratory course. We have designed a short laboratory project for the purification and identification of an "unknown" lactate dehydrogenase (LDH) isozyme that can…

  11. Isozyme variation in wild and cultivated pineapple

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Isozyme variation was studied in 161 accessions of pineapple including four species of Ananas and one of Pseudananas. Six enzyme systems (ADH, GPI, PGM, SKDH, TPI, UGPP) involving seven putative loci revealed 35 electromorphs . Considerable variation exists within and between species of Ananas. Sixt...

  12. Kynurenine Aminotransferase Isozyme Inhibitors: A Review

    PubMed Central

    Nematollahi, Alireza; Sun, Guanchen; Jayawickrama, Gayan S.; Church, W. Bret

    2016-01-01

    Kynurenine aminotransferase isozymes (KATs 1–4) are members of the pyridoxal-5’-phosphate (PLP)-dependent enzyme family, which catalyse the permanent conversion of l-kynurenine (l-KYN) to kynurenic acid (KYNA), a known neuroactive agent. As KATs are found in the mammalian brain and have key roles in the kynurenine pathway, involved in different categories of central nervous system (CNS) diseases, the KATs are prominent targets in the quest to treat neurodegenerative and cognitive impairment disorders. Recent studies suggest that inhibiting these enzymes would produce effects beneficial to patients with these conditions, as abnormally high levels of KYNA are observed. KAT-1 and KAT-3 share the highest sequence similarity of the isozymes in this family, and their active site pockets are also similar. Importantly, KAT-2 has the major role of kynurenic acid production (70%) in the human brain, and it is considered therefore that suitable inhibition of this isozyme would be most effective in managing major aspects of CNS diseases. Human KAT-2 inhibitors have been developed, but the most potent of them, chosen for further investigations, did not proceed in clinical studies due to the cross toxicity caused by their irreversible interaction with PLP, the required cofactor of the KAT isozymes, and any other PLP-dependent enzymes. As a consequence of the possibility of extensive undesirable adverse effects, it is also important to pursue KAT inhibitors that reversibly inhibit KATs and to include a strategy that seeks compounds likely to achieve substantial interaction with regions of the active site other than the PLP. The main purpose of this treatise is to review the recent developments with the inhibitors of KAT isozymes. This treatise also includes analyses of their crystallographic structures in complex with this enzyme family, which provides further insight for researchers in this and related studies. PMID:27314340

  13. Kynurenine Aminotransferase Isozyme Inhibitors: A Review.

    PubMed

    Nematollahi, Alireza; Sun, Guanchen; Jayawickrama, Gayan S; Church, W Bret

    2016-01-01

    Kynurenine aminotransferase isozymes (KATs 1-4) are members of the pyridoxal-5'-phosphate (PLP)-dependent enzyme family, which catalyse the permanent conversion of l-kynurenine (l-KYN) to kynurenic acid (KYNA), a known neuroactive agent. As KATs are found in the mammalian brain and have key roles in the kynurenine pathway, involved in different categories of central nervous system (CNS) diseases, the KATs are prominent targets in the quest to treat neurodegenerative and cognitive impairment disorders. Recent studies suggest that inhibiting these enzymes would produce effects beneficial to patients with these conditions, as abnormally high levels of KYNA are observed. KAT-1 and KAT-3 share the highest sequence similarity of the isozymes in this family, and their active site pockets are also similar. Importantly, KAT-2 has the major role of kynurenic acid production (70%) in the human brain, and it is considered therefore that suitable inhibition of this isozyme would be most effective in managing major aspects of CNS diseases. Human KAT-2 inhibitors have been developed, but the most potent of them, chosen for further investigations, did not proceed in clinical studies due to the cross toxicity caused by their irreversible interaction with PLP, the required cofactor of the KAT isozymes, and any other PLP-dependent enzymes. As a consequence of the possibility of extensive undesirable adverse effects, it is also important to pursue KAT inhibitors that reversibly inhibit KATs and to include a strategy that seeks compounds likely to achieve substantial interaction with regions of the active site other than the PLP. The main purpose of this treatise is to review the recent developments with the inhibitors of KAT isozymes. This treatise also includes analyses of their crystallographic structures in complex with this enzyme family, which provides further insight for researchers in this and related studies. PMID:27314340

  14. Lactate dehydrogenase X, malate dehydrogenase and total protein in rat spermatozoa during epididymal transit.

    PubMed

    Vermouth, N T; Carriazo, C S; Ponce, R H; Blanco, A

    1986-01-01

    Lactate dehydrogenase isozyme X (LDH X), malate dehydrogenase (MDH) and total soluble protein have been determined in lysates of spermatozoa isolated from caput, corpus and cauda of rat epididymis. Transit of spermatozoa through epididymis is accompanied by a reduction of LDH X, MDH and total protein per cell in sexually rested animals. The profiles of reduction along epididymal segments are different for the three variables studied. Mating with receptive females during the 5 days prior to determinations increases significantly the levels of MDH in spermatozoa from all sections of epididymis and produces increase of total soluble protein in the cells contained in cauda. PMID:3956158

  15. Microbial Engineering for Aldehyde Synthesis

    PubMed Central

    Kunjapur, Aditya M.

    2015-01-01

    Aldehydes are a class of chemicals with many industrial uses. Several aldehydes are responsible for flavors and fragrances present in plants, but aldehydes are not known to accumulate in most natural microorganisms. In many cases, microbial production of aldehydes presents an attractive alternative to extraction from plants or chemical synthesis. During the past 2 decades, a variety of aldehyde biosynthetic enzymes have undergone detailed characterization. Although metabolic pathways that result in alcohol synthesis via aldehyde intermediates were long known, only recent investigations in model microbes such as Escherichia coli have succeeded in minimizing the rapid endogenous conversion of aldehydes into their corresponding alcohols. Such efforts have provided a foundation for microbial aldehyde synthesis and broader utilization of aldehydes as intermediates for other synthetically challenging biochemical classes. However, aldehyde toxicity imposes a practical limit on achievable aldehyde titers and remains an issue of academic and commercial interest. In this minireview, we summarize published efforts of microbial engineering for aldehyde synthesis, with an emphasis on de novo synthesis, engineered aldehyde accumulation in E. coli, and the challenge of aldehyde toxicity. PMID:25576610

  16. Betaine aldehyde, betaine, and choline levels in rat livers during ethanol metabolism.

    PubMed

    Chern, M K; Gage, D A; Pietruszko, R

    2000-12-01

    Betaine aldehyde levels were determined in rat livers following 4 weeks of ethanol feeding, employing the Lieber-De Carli liquid diet. The results showed that the levels of betaine aldehyde are unaffected by alcohol feeding to rats. These levels in both experimental and control animals were found to be quite low, 5.5 nmol/g liver. Betaine aldehyde levels have not been determined previously in mammalian liver because of methodological difficulties. This investigation employed fast atom bombardment-mass spectroscopy to determine the levels of betaine aldehyde, betaine, and choline. The decrease in betaine levels following ethanol administration confirmed the results of other investigators. Choline levels determined during this investigation were lower than previously reported. The reason for starting this investigation was the fact that the enzyme that catalyzes betaine aldehyde dehydrogenation to betaine, which is distributed in both mitochondria and the cytoplasm, was found to also metabolize acetaldehyde with K(m) and V(max) values lower than those for betaine aldehyde. Thus, it appeared likely that the metabolism of acetaldehyde during ethanol metabolism might inhibit betaine aldehyde conversion to betaine and thereby result in decreased betaine levels (Barak et al., Alcohol 13: 395-398, 1996). The fact that betaine aldehyde levels in alcohol-fed animals were similar to those in controls demonstrates that competition between acetaldehyde and betaine aldehyde for the same enzyme does not occur. This complete lack of competition suggests that betaine aldehyde dehydrogenase in the mitochondrial matrix may totally metabolize betaine aldehyde to betaine without any involvement of cytoplasmic betaine aldehyde dehydrogenase. PMID:11077045

  17. Peroxidase Isozymes from Meloidogyne spp. and Their Origin

    PubMed Central

    Starr, J. L.

    1979-01-01

    Two peroxidase isozymes (Ef 0.43 and 0.53) were detected by electrophoretic analysis in homogenates of Meloidogyne arenaria, M. hapla, M. javanica, and M. incognita females reared on tomato. No peroxidase isozymes were detected electrophoretically in homogenates of adult males, preparasitic larvae, or eggs. Peroxidase isozymes from females reared on bean, eggplant, or tobacco differed from those from females reared on tomato. Bean and eggplant populations had a single peroxidase isozyme each, respectively Ef 0.21 and 0.28. No peroxidase isozymes were detected in tobacco populations under the conditions used, although total activity assays did reveal low levels of peroxidase activity in homogenates of tobacco populations. The peroxidase isozymes detected in females reared on tomato or bean appear similar to the peroxidase isozymes present in root-knot galls, adjacent ungalled roots, and roots from uninoculated plants of the corresponding hosts. The probability is discussed that most of the peroxittase activity associated with Meloidogyne spp. females is of host origin. PMID:19305520

  18. Aldehyde-stabilized cryopreservation.

    PubMed

    McIntyre, Robert L; Fahy, Gregory M

    2015-12-01

    We describe here a new cryobiological and neurobiological technique, aldehyde-stabilized cryopreservation (ASC), which demonstrates the relevance and utility of advanced cryopreservation science for the neurobiological research community. ASC is a new brain-banking technique designed to facilitate neuroanatomic research such as connectomics research, and has the unique ability to combine stable long term ice-free sample storage with excellent anatomical resolution. To demonstrate the feasibility of ASC, we perfuse-fixed rabbit and pig brains with a glutaraldehyde-based fixative, then slowly perfused increasing concentrations of ethylene glycol over several hours in a manner similar to techniques used for whole organ cryopreservation. Once 65% w/v ethylene glycol was reached, we vitrified brains at -135 °C for indefinite long-term storage. Vitrified brains were rewarmed and the cryoprotectant removed either by perfusion or gradual diffusion from brain slices. We evaluated ASC-processed brains by electron microscopy of multiple regions across the whole brain and by Focused Ion Beam Milling and Scanning Electron Microscopy (FIB-SEM) imaging of selected brain volumes. Preservation was uniformly excellent: processes were easily traceable and synapses were crisp in both species. Aldehyde-stabilized cryopreservation has many advantages over other brain-banking techniques: chemicals are delivered via perfusion, which enables easy scaling to brains of any size; vitrification ensures that the ultrastructure of the brain will not degrade even over very long storage times; and the cryoprotectant can be removed, yielding a perfusable aldehyde-preserved brain which is suitable for a wide variety of brain assays. PMID:26408851

  19. General and Versatile Autoinhibition of PLC Isozymes

    SciTech Connect

    Hicks, Stephanie N.; Jezyk, Mark R.; Gershburg, Svetlana; Seifert, Jason P.; Harden, T. Kendall; Sondek, John

    2008-10-31

    Phospholipase C (PLC) isozymes are directly activated by heterotrimeric G proteins and Ras-like GTPases to hydrolyze phosphatidylinositol 4,5-bisphosphate into the second messengers diacylglycerol and inositol 1,4,5-trisphosphate. Although PLCs play central roles in myriad signaling cascades, the molecular details of their activation remain poorly understood. As described here, the crystal structure of PLC-{beta}2 illustrates occlusion of the active site by a loop separating the two halves of the catalytic TIM barrel. Removal of this insertion constitutively activates PLC-{beta}2 without ablating its capacity to be further stimulated by classical G protein modulators. Similar regulation occurs in other PLC members, and a general mechanism of interfacial activation at membranes is presented that provides a unifying framework for PLC activation by diverse stimuli.

  20. Nicotinamide Cofactors Suppress Active-Site Labeling of Aldehyde Dehydrogenases.

    PubMed

    Stiti, Naim; Chandrasekar, Balakumaran; Strubl, Laura; Mohammed, Shabaz; Bartels, Dorothea; van der Hoorn, Renier A L

    2016-06-17

    Active site labeling by (re)activity-based probes is a powerful chemical proteomic tool to globally map active sites in native proteomes without using substrates. Active site labeling is usually taken as a readout for the active state of the enzyme because labeling reflects the availability and reactivity of active sites, which are hallmarks for enzyme activities. Here, we show that this relationship holds tightly, but we also reveal an important exception to this rule. Labeling of Arabidopsis ALDH3H1 with a chloroacetamide probe occurs at the catalytic Cys, and labeling is suppressed upon nitrosylation and oxidation, and upon treatment with other Cys modifiers. These experiments display a consistent and strong correlation between active site labeling and enzymatic activity. Surprisingly, however, labeling is suppressed by the cofactor NAD(+), and this property is shared with other members of the ALDH superfamily and also detected for unrelated GAPDH enzymes with an unrelated hydantoin-based probe in crude extracts of plant cell cultures. Suppression requires cofactor binding to its binding pocket. Labeling is also suppressed by ALDH modulators that bind at the substrate entrance tunnel, confirming that labeling occurs through the substrate-binding cavity. Our data indicate that cofactor binding adjusts the catalytic Cys into a conformation that reduces the reactivity toward chloroacetamide probes. PMID:26990764

  1. Immunolocalization of betaine aldehyde dehydrogenase in porcine kidney.

    PubMed

    Figueroa-Soto, C G; Lopez-Cervantes, G; Valenzuela-Soto, E M

    1999-05-19

    Polyclonal anti-BADH serum was raised in rabbits against native BADH purified from porcine kidney. The antiserum cross-reacted strongly with BADH purified from kidney, Amaranthus palmierii, and Pseudomona aeuroginosa (1:1000), and weakly with Amaranthus hypochondriacus L (1:100). Antibodies bound to purified native kidney BADH in immunoblots showed a major band of an apparent molecular mass of 340 kDa and a subunit with an apparent molecular mass of 52 kDa. Data on activity assays showed higher activity in cortex sections (81.3 nmol/min/mg protein) than in medulla sections (21.3 nmol/min/mg protein). Immunolocalization of BADH in kidney tissue sections showed that BADH is found in cortex and medulla. In inner medulla, the enzyme was mainly localized in cells surrounding the tubules. Western blot analysis on extracts from the cortex and medulla sections showed higher concentration of BADH protein in cortex than in medulla. These results were in accordance with immunolocalization and activity analysis. PMID:10329454

  2. Phylogeny congruence analysis and isozyme classification: the pyruvate kinase system.

    PubMed

    Guderley, H; Fournier, P; Auclair, J C

    1989-09-22

    As the isozymes of pyruvate kinase (PK) are best known in rats, the characteristics of the rat isozymes are generally used to classify the PK isozymes in other species. Given the discrepancies generated by this classification by analogy, we evaluated a classification using a phylogeny congruence analysis of the compositional relatedness of vertebrate PK's. While our phylogenetic analysis confirmed the well established separation of the L and R isozymes from the K and M isozymes, its power became most evident in the identification of non-orthologous (or variant) forms of PK. Our analysis emphasized the uniqueness of chicken liver PK which cannot be classified either as a K or an L isozyme, confirmed that tumors express a variety of forms of PK, and indicated that lungs systematically express PK's which are not orthologous with PK's from other tissues. The determination of orthology by the phylogeny congruence analysis assumes that the structural data from different sources are subject to similar methodological error. However, we cannot reject the possibility that an apparent lack of orthology be due to artifacts during purification and analysis. PMID:2615396

  3. Antioxidant and isozyme features of two strains of Laminaria japonica (Phaeophyceae)

    NASA Astrophysics Data System (ADS)

    Wang, You; Tang, Xuexi; Li, Yongqi; Yu, Zhiming

    2007-01-01

    Healthy sporophytes of two gametophyte mutants of Laminaria japonica with different heat resistances: kelp 901 ( 901, with comparatively stronger heat-resistance) and Rongcheng No.1 ( RC, sensitive to heat stress), were respectively collected during October to December 2002 from Yantai and Rongcheng Sea Farm in the Shandong Peninsula of China. The contents of some biochemical materials and antioxidant capacity were analyzed under controlled laboratory conditions to identify if there is any relation between the overall antioxidant capacity and the heat-resistance in L. japonica and to understand possible mechanism of heat-resistance. Results show that: (1) the overall antioxidant capacity in healthy sporophyte of 901, such as vitamin E, polyphenol, and ascorbic acid contents and the enzymatic activity of SOD, POD, CAT, Gpx, PPO, and PAL, were not always higher than that of RC under controlled laboratory conditions, and no significance ( P>0.05) was shown in total antioxidant capacity (T-AOC) in 901 and RC. Result suggested that the difference in antioxidant capacity was not a decisive factor for different heat-resistances in L. japonica; (2) the simultaneous assay on isozymes was carried out using vertical polyacrylamide gel electrophoresis (PAGE). Considerable differences in peroxide (PRX), malate dehydrogenase (MDH), malic enzyme (ME), polyphenol oxidase (PPO) and glutamate dehydrogenase (GDH) were obtained in 901 and RC from either the band number, relative mobility ( R f ), or staining intensity, and ME could be used as an indicator to distinguish healthy sporophyte of 901 and RC under controlled laboratory conditions.

  4. Alcohol, Aldehydes, Adducts and Airways.

    PubMed

    Sapkota, Muna; Wyatt, Todd A

    2015-01-01

    Drinking alcohol and smoking cigarettes results in the formation of reactive aldehydes in the lung, which are capable of forming adducts with several proteins and DNA. Acetaldehyde and malondialdehyde are the major aldehydes generated in high levels in the lung of subjects with alcohol use disorder who smoke cigarettes. In addition to the above aldehydes, several other aldehydes like 4-hydroxynonenal, formaldehyde and acrolein are also detected in the lung due to exposure to toxic gases, vapors and chemicals. These aldehydes react with nucleophilic targets in cells such as DNA, lipids and proteins to form both stable and unstable adducts. This adduction may disturb cellular functions as well as damage proteins, nucleic acids and lipids. Among several adducts formed in the lung, malondialdehyde DNA (MDA-DNA) adduct and hybrid malondialdehyde-acetaldehyde (MAA) protein adducts have been shown to initiate several pathological conditions in the lung. MDA-DNA adducts are pre-mutagenic in mammalian cells and induce frame shift and base-pair substitution mutations, whereas MAA protein adducts have been shown to induce inflammation and inhibit wound healing. This review provides an insight into different reactive aldehyde adducts and their role in the pathogenesis of lung disease. PMID:26556381

  5. MASS SPECTROMETRY OF FATTY ALDEHYDES

    PubMed Central

    Berdyshev, Evgeny V.

    2011-01-01

    Fatty aldehydes are important components of the cellular lipidome. Significant interest has been developed towards the analysis of the short chain α,β-unsaturated and hydroxylated aldehydes formed as a result of oxidation of polyunsaturated fatty acids. Multiple gas chromatography-mass spectrometry (GC/MS) and subsequently liquid chromatography-mass spectrometry (LC/MS) approaches have been developed to identify and quantify short-chain as well as long-chain fatty aldehydes. Due to the ability to non-enzymaticaly form Schiff bases with amino groups of proteins, lipids, and with DNA guanidine, free aldehydes are viewed as a marker or metric of fatty acid oxidation and not the part of intracellular signaling pathways which has significantly limited the overall attention this group of molecules have received. This review provides an overview of current GC/MS and LC/MS approaches of fatty aldehyde analysis as well as discusses technical challenges standing in the way of free fatty aldehyde quantitation. PMID:21930240

  6. Alcohol, Aldehydes, Adducts and Airways

    PubMed Central

    Sapkota, Muna; Wyatt, Todd A.

    2015-01-01

    Drinking alcohol and smoking cigarettes results in the formation of reactive aldehydes in the lung, which are capable of forming adducts with several proteins and DNA. Acetaldehyde and malondialdehyde are the major aldehydes generated in high levels in the lung of subjects with alcohol use disorder who smoke cigarettes. In addition to the above aldehydes, several other aldehydes like 4-hydroxynonenal, formaldehyde and acrolein are also detected in the lung due to exposure to toxic gases, vapors and chemicals. These aldehydes react with nucleophilic targets in cells such as DNA, lipids and proteins to form both stable and unstable adducts. This adduction may disturb cellular functions as well as damage proteins, nucleic acids and lipids. Among several adducts formed in the lung, malondialdehyde DNA (MDA-DNA) adduct and hybrid malondialdehyde-acetaldehyde (MAA) protein adducts have been shown to initiate several pathological conditions in the lung. MDA-DNA adducts are pre-mutagenic in mammalian cells and induce frame shift and base-pair substitution mutations, whereas MAA protein adducts have been shown to induce inflammation and inhibit wound healing. This review provides an insight into different reactive aldehyde adducts and their role in the pathogenesis of lung disease. PMID:26556381

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

    PubMed Central

    Rizzo, William B.

    2014-01-01

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

  8. Structure and function of mammalian aldehyde oxidases.

    PubMed

    Terao, Mineko; Romão, Maria João; Leimkühler, Silke; Bolis, Marco; Fratelli, Maddalena; Coelho, Catarina; Santos-Silva, Teresa; Garattini, Enrico

    2016-04-01

    Mammalian aldehyde oxidases (AOXs; EC1.2.3.1) are a group of conserved proteins belonging to the family of molybdo-flavoenzymes along with the structurally related xanthine dehydrogenase enzyme. AOXs are characterized by broad substrate specificity, oxidizing not only aromatic and aliphatic aldehydes into the corresponding carboxylic acids, but also hydroxylating a series of heteroaromatic rings. The number of AOX isoenzymes expressed in different vertebrate species is variable. The two extremes are represented by humans, which express a single enzyme (AOX1) in many organs and mice or rats which are characterized by tissue-specific expression of four isoforms (AOX1, AOX2, AOX3, and AOX4). In vertebrates each AOX isoenzyme is the product of a distinct gene consisting of 35 highly conserved exons. The extant species-specific complement of AOX isoenzymes is the result of a complex evolutionary process consisting of a first phase characterized by a series of asynchronous gene duplications and a second phase where the pseudogenization and gene deletion events prevail. In the last few years remarkable advances in the elucidation of the structural characteristics and the catalytic mechanisms of mammalian AOXs have been made thanks to the successful crystallization of human AOX1 and mouse AOX3. Much less is known about the physiological function and physiological substrates of human AOX1 and other mammalian AOX isoenzymes, although the importance of these proteins in xenobiotic metabolism is fairly well established and their relevance in drug development is increasing. This review article provides an overview and a discussion of the current knowledge on mammalian AOX. PMID:26920149

  9. Differential Contribution of Lipoxygenase Isozymes to Nigrostriatal Vulnerability

    PubMed Central

    Chou, Vivian P.; Holman, Theodore R.

    2012-01-01

    The 5- and 12/15- lipoxygenase (LOX) isozymes have been implicated to contribute to disease development in CNS disorders such as Alzheimer's disease. These LOX isozymes are distinct in function, with differential effects on neuroinflammation, and the impact of the distinct isozymes in the pathogenesis of Parkinson's disease (PD) has not as yet been evaluated. To determine whether the isozymes contribute differently to nigrostriatal vulnerability, the effects of 5- and 12/15-LOX deficiency on dopaminergic tone under na ve and toxicant-challenged conditions were tested. In na ve mice deficient in 5-LOX expression, a modest but significant reduction (18.0% reduction vs. wildtype (WT)) in striatal dopamine (DA) was detected (n=6-8 per genotype). A concomitant decline in striatal tyrosine hydroxylase (TH) enzyme was also revealed in null 5-LOX vs. WT mice (26.2%); however, no changes in levels of DA or TH immunoreactivity were observed in null 12/15-LOX vs. WT mice. When challenged with the selective dopaminergic toxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), WT mice showed marked reduction in DA (31.9%) and robust astrocytic and microglial activation as compared to saline-treated animals. In contrast, null 5-LOX littermates demonstrated no significant striatal DA depletion or astrogliosis (as noted by Western blot analyses for GFAP immunoreactivity). In na ve null 12/15-LOX mice, no significant change in striatal DA values was observed compared to WT, and following MPTP treatment, the transgenics revealed striatal DA reduction similar to the challenged WT mice. Taken together, these data provide the first evidence that: (i) LOX isozymes are involved in the maintenance of normal dopaminergic function in the striatum, and (ii) the 5- and 12/15-LOX isozymes contribute differentially to striatal vulnerability in response to neurotoxicant challenge. PMID:23079635

  10. Benzene toxicity: emphasis on cytosolic dihydrodiol dehydrogenases

    SciTech Connect

    Bolcsak, L.E.

    1982-01-01

    Blood dyscrasias such as leukopenia and anemia have been clearly identified as consequences of chronic benzene exposure. The metabolites, phenol, catechol, and hydroquinone produced inhibition of /sup 59/Fe uptake in mice which followed the same time course as that produced by benzene. The inhibitor of benzene oxidation, 3-amino-1,2,4-triazole, mitigated the inhibitory effects of benzene and phenol only. These data support the contention that benzene toxicity is mediated by a metabolite and suggest that the toxicity of phenol is a consequence of its metabolism to hydroquinone and that the route of metabolism to catechol may also contribute to the production of toxic metabolite(s). The properties of mouse liver cytosolic dihydrodiol dehydrogenases were examined. These enzymes catalyze the NADP/sup +/-dependent oxidation of trans-1,2-dihydro-1,2-dihydroxybenzene (BDD) to catechol, a possible toxic metabolite of benzene produced via this metabolic route. Four distinct dihydrodiol dehydrogenases (DD1, DD2, DD3, and DD4) were purified to apparent homogeneity as judged by SDS polyacrylamide gel electrophoresis and isoelectric focusing. DD1 appeared to be identical to the major ketone reductase and 17..beta..-hydroxysteroid dehydrogenase activity in the liver. DD2 exhibited aldehyde reductase activity. DD3 and DD4 oxidized 17..beta..-hydroxysteroids, but no carbonyl reductase activity was detected. These relationships between BDD dehydrogenases and carbonyl reductase and/or 17..beta..-hydroxysteroid dehydrogenase activities were supported by several lines of evidence.

  11. Developmental changes in the pyruvate kinase isozymes of coho salmon.

    PubMed

    Guderley, H E; Cardenas, J M

    1979-04-01

    Pyruvate kinase exists as two major isozymes in coho salmon. As in mammals and birds, one form is present in the early embryo and maintains a wide tissue distribution in adults. This salmonid type K shows anodal migration during electrophoresis at pH 7.5. The appearence of functional musculature in the developing embryos. In adult animals this second form is the only pyruvate kinase in muscle. Brain, kidney, liver and gill contain primarily the type K pyruvate kinase while heart contains both major forms along with three intermediate forms which presumably constitute a hybrid set. Since there is no additional isozyme restricted to gluconeogenic tissues, we conclude that a type L isozyme has not developed in these animals. The two major isozymes are immunologically distincy. Both forms are dubject to fructose 1,6-bisphosphate activation of phosphoenolpyruvate binding, but the magnitude of the effect is small. The affinities for phosphoenolpyruvate are similar, but salmon type K has hyperbolic saturation curves with this substrate and type M has sigmoidal saturation curves. While the immunological data indicates considerable divergence in structure, the kinetic parameters of the two forms have remained relatively similar. PMID:469475

  12. New phosphonate reagents for aldehyde homologation

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  13. N-acylethanolamines as novel alcohol dehydrogenase 3 substrates.

    PubMed

    Ivkovic, Milena; Dempsey, Daniel R; Handa, Sumit; Hilton, Joshua H; Lowe, Edward W; Merkler, David J

    2011-02-15

    N-acylethanolamines (NAEs) are members of the fatty acid amide family. The NAEs have been proposed to serve as metabolic precursors to N-acylglycines (NAGs). The sequential oxidation of the NAEs by an alcohol dehydrogenase and an aldehyde dehydrogenase would yield the N-acylglycinals and/or the NAGs. Alcohol dehydrogenase 3 (ADH3) is one enzyme that might catalyze this reaction. To define a potential role for ADH3 in NAE catabolism, we synthesized a set of NAEs and evaluated these as ADH3 substrates. NAEs were oxidized by ADH3, yielding the N-acylglycinals as the product. The (V/K)(app) values for the NAEs included here were low relative to cinnamyl alcohol. Our data show that the NAEs can serve as alcohol dehydrogenase substrates. PMID:21144815

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  15. Glucose-6-phosphate dehydrogenase

    MedlinePlus

    ... 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 type of ...

  16. Different Functions of Phylogenetically Distinct Bacterial Complex I Isozymes

    PubMed Central

    Spero, Melanie A.; Brickner, Joshua R.; Mollet, Jordan T.; Pisithkul, Tippapha; Amador-Noguez, Daniel

    2016-01-01

    ABSTRACT NADH:quinone oxidoreductase (complex I) is a bioenergetic enzyme that transfers electrons from NADH to quinone, conserving the energy of this reaction by contributing to the proton motive force. While the importance of NADH oxidation to mitochondrial aerobic respiration is well documented, the contribution of complex I to bacterial electron transport chains has been tested in only a few species. Here, we analyze the function of two phylogenetically distinct complex I isozymes in Rhodobacter sphaeroides, an alphaproteobacterium that contains well-characterized electron transport chains. We found that R. sphaeroides complex I activity is important for aerobic respiration and required for anaerobic dimethyl sulfoxide (DMSO) respiration (in the absence of light), photoautotrophic growth, and photoheterotrophic growth (in the absence of an external electron acceptor). Our data also provide insight into the functions of the phylogenetically distinct R. sphaeroides complex I enzymes (complex IA and complex IE) in maintaining a cellular redox state during photoheterotrophic growth. We propose that the function of each isozyme during photoheterotrophic growth is either NADH synthesis (complex IA) or NADH oxidation (complex IE). The canonical alphaproteobacterial complex I isozyme (complex IA) was also shown to be important for routing electrons to nitrogenase-mediated H2 production, while the horizontally acquired enzyme (complex IE) was dispensable in this process. Unlike the singular role of complex I in mitochondria, we predict that the phylogenetically distinct complex I enzymes found across bacterial species have evolved to enhance the functions of their respective electron transport chains. IMPORTANCE Cells use a proton motive force (PMF), NADH, and ATP to support numerous processes. In mitochondria, complex I uses NADH oxidation to generate a PMF, which can drive ATP synthesis. This study analyzed the function of complex I in bacteria, which contain more

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

    PubMed

    Wang, Xu; Ma, Menggen; Liu, Z Lewis; Xiang, Quanju; Li, Xi; Liu, Na; Zhang, Xiaoping

    2016-08-01

    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 reduction enzymes involved in this reaction remain largely unknown. In this study, we reported that an uncharacterized open reading frame PICST_72153 (putative GRE2) from S. stipitis was highly induced in response to furfural and HMF stresses. Overexpression of this gene in Saccharomyces cerevisiae improved yeast tolerance to furfural and HMF. GRE2 was identified as an aldehyde reductase which can reduce furfural to FM with either NADH or NADPH as the co-factor and reduce HMF to FDM with NADPH as the co-factor. This enzyme can also reduce multiple aldehydes to their corresponding alcohols. Amino acid sequence analysis indicated that it is a member of the subclass "intermediate" of the short-chain dehydrogenase/reductase (SDR) superfamily. Although GRE2 from S. stipitis is similar to GRE2 from S. cerevisiae in a three-dimensional structure, some differences were predicted. GRE2 from S. stipitis forms loops at D133-E137 and T143-N145 locations with two α-helices at E154-K157 and E252-A254 locations, different GRE2 from S. cerevisiae with an α-helix at D133-E137 and a β-sheet at T143-N145 locations, and two loops at E154-K157 and E252-A254 locations. This research provided guidelines for the study of other SDR enzymes from S. stipitis and other yeasts on tolerant mechanisms to aldehyde inhibitors derived from lignocellulosic biomass. PMID:27003269

  18. Pyruvate kinases of salmon: purification and comparison with the isozymes from birds and mammals.

    PubMed

    Guderley, H; Cardenas, J M

    1980-02-01

    Pyruvate kinase occurs as two major forms in coho salmon; the type M isozyme occurs primarily in muscle and heart, but type K has a more generalized tissue distribution, in parallel with the type K isozyme in other vertebrate systems. In order to assess the evolutionary relationships among the fish, avian, and mammalian isozymes of pyruvate kinase, we have purified the two isozymes from fish, have examined some of their physical properties, and have studied their immunological relationships to the avian and mammalian isozymes. Salmon type K is at least partially inactivated by antibody to bivine type L pyruvate kinase as well as by antibodies produced against chicken, bovine, and salmon type M isozymes. Salmon type M pyruvate kinase, on the other hand, is not significantly corss-reactive with the bovine type L isozyme, but is at least partially inactivated by antibodies produced against bovine or chicken type M isozymes. Mammalian type L pyruvate kinase is immunologically distinct from either mammalian type K or type M, but salmon type K has some structural features in common with all three mammalian isozymes. Thus, salmon fish type K pyruvate kinase could be similar to a primordial form that was antecedent to the three major differentiated isozymes of higher vertebrates. PMID:7373271

  19. Synthesis of 5'-Aldehyde Oligonucleotide.

    PubMed

    Lartia, Rémy

    2016-01-01

    Synthesis of oligonucleotide ending with an aldehyde functional group at their 5'-end (5'-AON) is possible for both DNA (5'-AODN) and RNA (5'-AORN) series irrespectively of the nature of the last nucleobase. The 5'-alcohol of on-support ODN is mildly oxidized under Moffat conditions. Transient protection of the resulting aldehyde by N,N'-diphenylethylenediamine derivatives allows cleavage, deprotection, and RP-HPLC purification of the protected 5'-AON. Finally, 5'-AON is deprotected by usual acetic acid treatment. In the aggregates, 5'-AON can be now synthesized and purified as routinely as non-modified ODNs, following procedures similar to the well-known "DMT-On" strategy. PMID:26967469

  20. Isozyme gene expression in potato tumors incited by Agrobacterium.

    PubMed

    Oliver, J L

    1986-06-01

    Two plant tumors (crown galls and hairy roots) were experimentally provoked on potato cv. 'Désirée' by oncogenic strains of Agrobacterium tumefaciens and A. rhizogenes. A marked shift in the expression of some organ-specific genes occurred in crown galls derived from the central zone of tubers: two novel isozyme genes (Est-B and Pox-E) were expressed, two others (Est-C and Pox-F) were suppressed and the remaining ones were maintained in the original state. When the starting tissue was the stem segment, a smaller shift occurred, namely the activation of Adh-A and the suppression of Pox-F. In all cases, the isozyme profiles characterizing all crown galls, whatever their origin, were identical. Under normal aeration conditions, Adh-A was not expressed in either tumoral or non-tumoral roots. However, under the relative anaerobic conditions of in vitro cultures, a difference existed between both types of roots: Adh-A was expressed in normal but not in tumoral roots. This means that hairy roots can tolerate higher levels of anaerobiosis without giving rise to an anaerobic response. For the remaining isozymes, no alteration occurred in either organized (hairy root) or unorganized (crown gall) tumors, as compared to the corresponding non-tumoral tissues (normal root and callus, respectively). PMID:24247945

  1. Characterization of lactate dehydrogenase enzyme in seminal plasma of Japanese quail (Coturnix coturnix japonica).

    PubMed

    Singh, R P; Sastry, K V H; Pandey, N K; Shit, N; Agrawal, R; Singh, K B; Mohan, Jag; Saxena, V K; Moudgal, R P

    2011-02-01

    Lactate dehydrogenase enzyme present in quail seminal plasma has been characterized. Polyacrylamide gel electrophoresis and subsequently with LDH specific staining of seminal plasma revealed a single isozyme in quail semen. Studies on substrate inhibition, pH for optimum activity and inhibitor (urea) indicated the isozyme present in the quail semen has catalytic properties like LDH-1 viz. H-type. Furthermore, unlike other mammalian species, electrophoretic and kinetic investigations did not support the existence of semen specific LDH-X isozyme in quail semen. The effect of exogenous lactate and pyruvate on sperm metabolic activity was also studied. The addition of 1 mM lactate or pyruvate to quail semen increased sperm metabolic activity. Our results suggested that both pyruvate and lactate could be used by quail spermatozoa to maintain their basic functions. Since the H-type isozyme is important for conversion of lactate to pyruvate under anaerobic conditions it was postulated that exogenous lactate being converted into pyruvate via LDH present in semen may be used by sperm mitochondria to generate ATP. During conversion of lactate to pyruvate NADH is being generated that may be useful for maintaining sperm mitochondrial membrane potential. PMID:21074838

  2. Isozymes of Ipomoea batatas catechol oxidase differ in catalase-like activity.

    PubMed

    Gerdemann, C; Eicken, C; Magrini, A; Meyer, H E; Rompel, A; Spener, F; Krebs, B

    2001-07-01

    The amino acid sequences of two isozymes of catechol oxidase from sweet potatoes (Ipomoea batatas) were determined by Edman degradation of BrCN cleavage fragments of the native protein and by sequencing of amplified cDNA fragments. Sequence alignment and phylogenetic analysis of plant catechol oxidases revealed about 80% equidistance between the two I. batatas catechol oxidases and approximately 40--60% to catechol oxidases of other plants. When H(2)O(2) was applied as substrate the 39 kDa isozyme, but not the 40 kDa isozyme, showed catalase-like activity. The structure of the 40 kDa isozyme was modeled on the basis of the published crystal structure of the 39 kDa isozyme [T. Klabunde et al., Nat. Struct. Biol. 5 (1998) 1084]. The active site model closely resembled that of the 39 kDa isozyme determined by crystallography, except for a mutation of Thr243 (40 kDa isozyme) to Ile241 (39 kDa isozyme) close to the dimetal center. This residue difference affects the orientation of the Glu238/236 residue, which is thought to be responsible for the catalase-like activity of the 39 kDa isozyme for which a catalytic mechanism is proposed. PMID:11451442

  3. Oxidation of cinnamyl alcohols and aldehydes by a basic peroxidase from lignifying Zinnia elegans hypocotyls.

    PubMed

    Barceló, A R; Pomar, F

    2001-08-01

    The xylem of 26-day old Zinnia elegans hypocotyls synthesizes lignins derived from coniferyl alcohol and sinapyl alcohol with a G/S ratio of 43/57 in the aryl-glycerol-beta-aryl ether core, as revealed by thioacidolysis. Thioacidolysis of Z. elegans lignins also reveals the presence of coniferyl aldehyde end groups linked by beta-0-4 bonds. Both coniferyl and sinapyl alcohols, as well as coniferyl and sinapyl aldehyde, are substrates of a xylem cell wall-located strongly basic peroxidase, which is capable of oxidizing them in the absence and in the presence of hydrogen peroxide. This peroxidase shows a particular affinity for cinnamyl aldehydes with kappa(M) values in the mu(M) range, and some specificity for syringyl-type phenols. The affinity of this strongly basic peroxidase for cinnamyl alcohols and aldehydes is similar to that shown by the preceding enzymes in the lignin biosynthetic pathway (microsomal 5-hydroxylases and cinnamyl alcohol dehydrogenase), which also use cinnamyl alcohols and aldehydes as substrates, indicating that the one-way highway of construction of the lignin macromolecule has no metabolic "potholes" in which the lignin building blocks might accumulate. This fact suggests a high degree of metabolic plasticity for this basic peroxidase, which has been widely conserved during the evolution of vascular plants, making it one of the driving forces in the evolution of plant lignin heterogeneity. PMID:11430983

  4. The thiocarbamate disulphide drug, disulfiram induces osteopenia in rats by inhibition of osteoblast function due to suppression of acetaldehyde dehydrogenase activity.

    PubMed

    Mittal, Monika; Khan, Kainat; Pal, Subhashis; Porwal, Konica; China, Shyamsundar Pal; Barbhuyan, Tarun K; Baghel, Khemraj S; Rawat, Tara; Sanyal, Sabyasachi; Bhadauria, Smrati; Sharma, Vishnu L; Chattopadhyay, Naibedya

    2014-05-01

    Dithiocarbamates (DTC), a sulfhydryl group containing compounds, are extensively used by humans that include metam and thiram due to their pesticide properties, and disulfiram (DSF) as an alcohol deterrent. We screened these DTC in an osteoblast viability assay. DSF exhibited the highest cytotoxicity (IC50 488nM). Loss in osteoblast viability and proliferation was due to induction of apoptosis via G1 arrest. DSF treatment to osteoblasts reduced glutathione (GSH) levels and exogenous addition of GSH prevented DSF-induced reactive oxygen species generation and osteoblast apoptosis. DSF also inhibited osteoblast differentiation in vitro and in vivo, and the effect was associated with inhibition of aldehyde dehydrogenase (ALDH) activity. Out of various ALDH isozymes, osteoblasts expressed only ALDH2 and DSF downregulated its transcript as well as activity. Alda-1, a specific activator of ALDH2, stimulated osteoblast differentiation. Subcutaneous injection of DSF over the calvarium of new born rats reduced the differentiation phenotype of calvarial osteoblasts but increased the mRNA levels of Runx-2 and osteocalcin. DSF treatment at a human-equivalent dose of 30 mg/kg p.o. to adult Sprague Dawley rats caused trabecular osteopenia and suppressed the formation of mineralized nodule by bone marrow stromal cells. Moreover, DSF diminished bone regeneration at the fracture site. In growing rats, DSF diminished growth plate height, primary and secondary spongiosa, mineralized osteoid and trabecular strength. Substantial decreased bone formation was also observed in the cortical site of these rats. We conclude that DSF has a strong osteopenia inducing effect by impairing osteoblast survival and differentiation due to the inhibition of ALDH2 function. PMID:24496638

  5. Cyanobacterial aldehyde deformylase oxygenation of aldehydes yields n-1 aldehydes and alcohols in addition to alkanes

    PubMed Central

    Aukema, Kelly G.; Makris, Thomas M.; Stoian, Sebastian A.; Richman, Jack E.; Münck, Eckard; Lipscomb, John D.; Wackett, Lawrence P.

    2013-01-01

    Aldehyde-deformylating oxygenase (ADO) catalyzes O2-dependent release of the terminal carbon of a biological substrate, octadecanal, to yield formate and heptadecane in a reaction that requires external reducing equivalents. We show here that ADO also catalyzes incorporation of an oxygen atom from O2 into the alkane product to yield alcohol and aldehyde products. Oxygenation of the alkane product is much more pronounced with C9-10 aldehyde substrates, so that use of nonanal as the substrate yields similar amounts of octane, octanal, and octanol products. When using doubly-labeled [1,2-13C]-octanal as the substrate, the heptane, heptanal and heptanol products each contained a single 13C-label in the C-1 carbons atoms. The only one-carbon product identified was formate. [18O]-O2 incorporation studies demonstrated formation of [18O]-alcohol product, but rapid solvent exchange prevented similar determination for the aldehyde product. Addition of [1-13C]-nonanol with decanal as the substrate at the outset of the reaction resulted in formation of [1-13C]-nonanal. No 13C-product was formed in the absence of decanal. ADO contains an oxygen-bridged dinuclear iron cluster. The observation of alcohol and aldehyde products derived from the initially formed alkane product suggests a reactive species similar to that formed by methane monooxygenase (MMO) and other members of the bacterial multicomponent monooxygenase family. Accordingly, characterization by EPR and Mössbauer spectroscopies shows that the electronic structure of the ADO cluster is similar, but not identical, to that of MMO hydroxylase component. In particular, the two irons of ADO reside in nearly identical environments in both the oxidized and fully reduced states, whereas those of MMOH show distinct differences. These favorable characteristics of the iron sites allow a comprehensive determination of the spin Hamiltonian parameters describing the electronic state of the diferrous cluster for the first time for

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

    PubMed

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

    2014-08-20

    Aromatic aldehydes are useful in numerous applications, especially as flavors, fragrances, and pharmaceutical precursors. However, microbial synthesis of aldehydes is hindered by rapid, endogenous, and redundant conversion of aldehydes to their corresponding alcohols. We report the construction of an Escherichia coli K-12 MG1655 strain with reduced aromatic aldehyde reduction (RARE) that serves as a platform for aromatic aldehyde biosynthesis. Six genes with reported activity on the model substrate benzaldehyde were rationally targeted for deletion: three genes that encode aldo-keto reductases and three genes that encode alcohol dehydrogenases. Upon expression of a recombinant carboxylic acid reductase in the RARE strain and addition of benzoate during growth, benzaldehyde remained in the culture after 24 h, with less than 12% conversion of benzaldehyde to benzyl alcohol. Although individual overexpression results demonstrated that all six genes could contribute to benzaldehyde reduction in vivo, additional experiments featuring subset deletion strains revealed that two of the gene deletions were dispensable under the conditions tested. The engineered strain was next investigated for the production of vanillin from vanillate and succeeded in preventing formation of the byproduct vanillyl alcohol. A pathway for the biosynthesis of vanillin directly from glucose was introduced and resulted in a 55-fold improvement in vanillin titer when using the RARE strain versus the wild-type strain. Finally, synthesis of the chiral pharmaceutical intermediate L-phenylacetylcarbinol (L-PAC) was demonstrated from benzaldehyde and glucose upon expression of a recombinant mutant pyruvate decarboxylase in the RARE strain. Beyond allowing accumulation of aromatic aldehydes as end products in E. coli, the RARE strain expands the classes of chemicals that can be produced microbially via aldehyde intermediates. PMID:25076127

  7. Process for producing furan from furfural aldehyde

    DOEpatents

    Diebold, James P.; Evans, Robert J.

    1988-01-01

    A process of producing furan and derivatives thereof is disclosed. The process includes generating furfural aldehyde vapors and then passing those vapors over a zeolite catalyst at a temperature and for a residence time effective to decarbonylate the furfural aldehydes to form furans and derivatives thereof. The resultant furan vapors and derivatives are then separated. In a preferred form, the furfural aldehyde vapors are generated during the process of converting biomass materials to liquid and gaseous fuels.

  8. Microsphere coated substrate containing reactive aldehyde groups

    NASA Technical Reports Server (NTRS)

    Rembaum, Alan (Inventor); Yen, Richard C. K. (Inventor)

    1984-01-01

    A synthetic organic resin is coated with a continuous layer of contiguous, tangential, individual microspheres having a uniform diameter preferably between 100 Angstroms and 2000 Angstroms. The microspheres are an addition polymerized polymer of an unsaturated aldehyde containing 4 to 20 carbon atoms and are covalently bonded to the substrate by means of high energy radiation grafting. The microspheres contain reactive aldehyde groups and can form conjugates with proteins such as enzymes or other aldehyde reactive materials.

  9. Process for producing furan from furfural aldehyde

    DOEpatents

    Diebold, J.P.; Evans, R.J.

    1987-04-06

    A process of producing furan and derivatives thereof as disclosed. The process includes generating furfural aldehyde vapors and then passing those vapors over a zeolite catalyst at a temperature and for a residence time effective to decarbonylate the furfural aldehydes to form furans and derivatives thereof. The resultant furan vapors and derivatives are then separated. In a preferred form, the furfural aldehyde vapors are generated during the process of converting biomass materials to liquid and gaseous fuels.

  10. Chromate reduction by rabbit liver aldehyde oxidase

    SciTech Connect

    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.

  11. DIFFERENTIATING THE TOXICITY OF CARCINOGENIC ALDEHYDES FROM NONCARCINOGENIC ALDEHYDES IN THE RAT NOSE USING CDNA ARRAYS

    EPA Science Inventory

    Differentiating the Toxicity of Carcinogenic Aldehydes from Noncarcinogenic Aldehydes in the Rat Nose Using cDNA Arrays.

    Formaldehyde is a widely used aldehyde in many industrial settings, the tanning process, household products, and is a contaminant in cigarette smoke. H...

  12. Intracellular compartmentation of isozymes of sugar phosphate metabolism in green leaves.

    PubMed

    Schnarrenberger, C; Herbert, M; Krüger, I

    1983-01-01

    The present paper has summarized evidence for the presence of two isozymes for many enzyme activities of sugar phosphate metabolism in plant leaves. These two isozymes are clearly compartmentalized in the chloroplasts and in the cytosol of plant leaf cells. In C4 plants there exists an additional isozyme in the mesophyll cells of these leaves in addition to the two isozymes in the bundle sheath cells. Such cell-compartment-specific and cell-specific isozymes provide duplicate (and possibly triplicate) enzyme systems for complete or almost complete pathways (ie, glycolysis, gluconeogenesis, and the oxidative pentose phosphate pathway). They provide a basis for the understanding as to how many isozymes one may expect in plants. They also provide a challenge to determine what their function is particularly in the differential regulation of metabolic pathways in different cell compartments. Based on his genetic analyses Weeden [1981] has recently proposed a model for the evolution of chloroplast-specific isozymes of sugar phosphate metabolism. This model rests on the endosymbiotic theory for the origin of chloroplasts. It still is highly speculative. However, cell-compartment specific isozymes may eventually provide a means of studying plant evolution, especially if we succeed in analyzing their primary structure. PMID:6629713

  13. DISTRIBUTION OF THE GLUTAMINE SYNTHETASE ISOZYME GSP1 IN MAIZE (ZEA MAYS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Higher plants contain families of glutamine synthetase (GS) isozymes. In maize (Zea mays L.), GSp1, the predominant GS isozyme of the developing kernel, is abundant in the pedicel and pericarp, but absent from the endosperm and embryo. Determination of GSp1 tissue distribution in vegetative tissue...

  14. Aldehyde-containing urea-absorbing polysaccharides

    NASA Technical Reports Server (NTRS)

    Mueller, W. A.; Hsu, G. C.; Marsh, H. E., Jr. (Inventor)

    1977-01-01

    A novel aldehyde containing polymer (ACP) is prepared by reaction of a polysaccharide with periodate to introduce aldehyde groups onto the C2 - C3 carbon atoms. By introduction of ether and ester groups onto the pendant primary hydroxyl solubility characteristics are modified. The ACP is utilized to absorb nitrogen bases such as urea in vitro or in vivo.

  15. EMISSIONS OF ODOROUS ALDEHYDES FROM ALKYD PAINT

    EPA Science Inventory

    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 environmental chambers. It was found that, for each alkyd paint applied, more than 2 mg of ...

  16. A protein kinase C isozyme is translocated to cytoskeletal elements on activation.

    PubMed Central

    Mochly-Rosen, D; Henrich, C J; Cheever, L; Khaner, H; Simpson, P C

    1990-01-01

    Protein kinase C (PKC)1 isozymes comprise a family of related cytosolic kinases that translocate to the cell particulate fraction on stimulation. The activated enzyme is thought to be on the plasma membrane. However, phosphorylation of protein substrates occurs throughout the cell and is inconsistent with plasma membrane localization. Using an isozyme-specific monoclonal antibody we found that, on activation, this PKC isozyme translocates to myofibrils in cardiac myocytes and to microfilaments in fibroblasts. Translocation of this activated PKC isozyme to cytoskeletal elements may explain some of the effects of PKC on cell contractility and morphology. In addition, differences in the translocation site of individual isozymes--and, therefore, phosphorylation of different substrates localized at these sites--may explain the diverse biological effects of PKC. Images PMID:2078573

  17. Comprehensive Characterization of Cytochrome P450 Isozyme Selectivity across Chemical Libraries

    PubMed Central

    Veith, Henrike; Southall, Noel; Huang, Ruili; James, Tim; Fayne, Darren; Artemenko, Natalia; Shen, Min; Inglese, James; Austin, Christopher P.; Lloyd, David G.; Auld, Douglas S.

    2009-01-01

    The cytochrome P450 (CYP) gene family strongly influences drug development. We determined potency values for 17,143 compounds against recombinant CYP 1A2, 2C9, 2C19, 2D6, and 3A4 enzymes through an in vitro bioluminescent assay. The compound collections included substances from typical libraries and FDA-approved drugs. Cross-library isozyme inhibition (30–78%) was observed with important differences between collections. While only 7% of the typical screening library was inactive against all five isozymes, 33% of FDA-approved drugs were inactive, reflecting the optimized pharmacological properties of the latter. Unexpectedly, drugs exhibited less activity towards the CYP 2C9 and 2C19 isozymes compared to un-optimized collections. We then identified substructures that differentiated between the five isozymes as well as substructures trending towards active or inactive categories. We describe here a pharmacological compendium to further the understanding of CYP isozymes. PMID:19855396

  18. Electrophilicity and nucleophilicity of commonly used aldehydes.

    PubMed

    Pratihar, Sanjay

    2014-08-14

    The present approach for determining the electrophilicity (E) and nucleophilicity (N) of aldehydes includes a kinetic study of KMNO4 oxidation and NaBH4 reduction of aldehydes. A transition state analysis of the KMNO4 promoted aldehyde oxidation reaction has been performed, which shows a very good correlation with experimental results. The validity of the experimental method has been tested using the experimental activation parameters of the two reactions. The utility of the present approach is further demonstrated by the theoretical versus experimental relationship, which provides easy access to E and N values for various aldehydes and offers an at-a-glance assessment of the chemical reactivity of aldehydes in various reactions. PMID:24979574

  19. Crystal structure of Arabidopsis thaliana cytokinin dehydrogenase

    SciTech Connect

    Bae, Euiyoung; Bingman, Craig A.; Bitto, Eduard; Aceti, David J.; Phillips, Jr., George N.

    2008-08-13

    Since first discovered in Zea mays, cytokinin dehydrogenase (CKX) genes have been identified in many plants including rice and Arabidopsis thaliana, which possesses CKX homologues (AtCKX1-AtCKX7). So far, the three-dimensional structure of only Z. mays CKX (ZmCKX1) has been determined. The crystal structures of ZmCKX1 have been solved in the native state and in complex with reaction products and a slowly reacting substrate. The structures revealed four glycosylated asparagine residues and a histidine residue covalently linked to FAD. Combined with the structural information, recent biochemical analyses of ZmCKX1 concluded that the final products of the reaction, adenine and a side chain aldehyde, are formed by nonenzymatic hydrolytic cleavage of cytokinin imine products resulting directly from CKX catalysis. Here, we report the crystal structure of AtCKX7 (gene locus At5g21482.1, UniProt code Q9FUJ1).

  20. Toward aldehyde and alkane production by removing aldehyde reductase activity in Escherichia coli

    PubMed Central

    Rodriguez, Gabriel M.; Atsumi, Shota

    2015-01-01

    Advances in synthetic biology and metabolic engineering have enabled the construction of novel biological routes to valuable chemicals using suitable microbial hosts. Aldehydes serve as chemical feedstocks in the synthesis of rubbers, plastics, and other larger molecules. Microbial production of alkanes is dependent on the formation of a fatty aldehyde intermediate which is converted to an alkane by an aldehyde deformylating oxygenase (ADO). However, microbial hosts such as Escherichia coli are plagued by many highly active endogenous aldehyde reductases (ALRs) that convert aldehydes to alcohols, which greatly complicates strain engineering for aldehyde and alkane production. It has been shown that the endogenous ALR activity outcompetes the ADO enzyme for fatty aldehyde substrate. The large degree of ALR redundancy coupled with an incomplete database of ALRs represents a significant obstacle in engineering E. coli for either aldehyde or alkane production. In this study, we identified 44 ALR candidates encoded in the E. coli genome using bioinformatics tools, and undertook a comprehensive screening by measuring the ability of these enzymes to produce isobutanol. From the pool of 44 candidates, we found five new ALRs using this screening method (YahK, DkgA, GldA, YbbO, and YghA). Combined deletions of all 13 known ALRs resulted in a 90–99% reduction in endogenous ALR activity for a wide range of aldehyde substrates (C2–C12). Elucidation of the ALRs found in E. coli could guide one in reducing competing alcohol formation during alkane or aldehyde production. PMID:25108218

  1. S-nitrosomycothiol reductase and mycothiol are required for survival under aldehyde stress and biofilm formation in Mycobacterium smegmatis.

    PubMed

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

    2016-08-01

    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. © 2016 IUBMB Life, 68(8):621-628, 2016. PMID:27321674

  2. Comparative Diversity Analysis of Rflps and Isozymes within and among Populations of Hordeum Vulgare Ssp. Spontaneum

    PubMed Central

    Zhang, Q.; Maroof, MAS.; Kleinhofs, A.

    1993-01-01

    DNA restriction fragment length polymorphisms (RFLPs) and isozyme variation were surveyed in 268 accessions of a wild barley (Hordeum vulgare ssp. spontaneum) sampled from diverse ecogeographical areas in Israel and Iran. A total of 24 markers was used: 7 well characterized isozyme loci and 15 DNA probes which detected 17 putative loci and included three classes of DNA sequences (single copy, low copy and repetitive) representing all 7 barley chromosomes. Survey results indicated that both RFLPs and isozymes are highly polymorphic both within and among populations of this wild barley. The number of alleles per locus and average level of diversity do not differ between isozymes and RFLPs. However, the relative amounts of within vs. between population components vary greatly between these two sets of molecular markers. Isozymes demonstrated a larger amount of within population diversity, whereas RFLPs resolved a higher proportion of between population differentiation. Furthermore, RFLPs detected more heterozygosity than did isozymes. Both classes of markers resolved large numbers of multilocus combinations, the majority of which were represented by only one individual in the total sample. Up to 30% of the loci differ among individuals within populations, and about 50% of the loci differ among plants in different populations. While many important aspects of population diversity as determined by RFLPs are significantly correlated with those of isozymes, such correlation values are generally low, indicating that only a small proportion of the genetic variation detected by one class of markers can be predicted by the other. PMID:8102343

  3. Circadian rhythm of lactate dehydrogenase in rat testis.

    PubMed

    Vermouth, N T; Ponce, R H; Carriazo, C S; Blanco, A

    1984-01-01

    Activity of total lactate dehydrogenase (LDH) and of the isozyme X (LDH X or C4) have been determined at 2 hr intervals during 24 hr cycles in testis of adult rats maintained since birth in a photoperiod of 14 hr light: 10 hr dark. LDH X activity of epididymal sections (caput, corpus and cauda) from the same animals was also determined. Total LDH and LDH X activities in testis exhibited circadian rhythms with different timing. LDH X in the three portions of epididymis showed diurnal variations similar to those in testis. Rats subjected to constant light or constant dark presented marked modifications of LDH X profiles, indicating that the photoperiod plays a synchronizer role. While total soluble proteins did not show variations in testis of rats exposed to the photoperiod, a circadian rhythm was demonstrated in animals maintained in constant light or dark. PMID:6467917

  4. Plant Formate Dehydrogenase

    SciTech Connect

    John Markwell

    2005-01-10

    The research in this study identified formate dehydrogenase, an enzyme that plays a metabolic role on the periphery of one-carbon metabolism, has an unusual localization in Arabidopsis thaliana and that the enzyme has an unusual kinetic plasticity. These properties make it possible that this enzyme could be engineered to attempt to engineer plants with an improved photosynthetic efficiency. We have produced transgenic Arabidopsis and tobacco plants with increased expression of the formate dehydrogenase enzyme to initiate further studies.

  5. New ideas for an old enzyme: A short, question-based laboratory project for the purification and identification of an unknown LDH isozyme.

    PubMed

    Coleman, Aaron B

    2010-07-01

    Enzyme purification projects are an excellent way to introduce many aspects of protein biochemistry, but can be difficult to carry out under the constraints of a typical undergraduate laboratory course. We have designed a short laboratory project for the purification and identification of an "unknown" lactate dehydrogenase (LDH) isozyme that can fit into a multiproject course without consuming too many laboratory days. The streamlined purification utilizes ammonium sulfate precipitation, affinity chromatography, and size exclusion chromatography to give good recovery of LDH with minimal equipment requirements, and can be completed in three laboratory periods of 3-4 hours. As part of this, we have designed a novel, qualitative format for an LDH activity assay that allows students to rapidly screen their column chromatography fractions without the need of a spectrophotometer or plate reader. The analysis phase of the project is question-driven, and can be completed in two laboratory periods. The students must determine which purification technique was most effective by quantifying LDH activity and total protein content at each step of the purification, and then identify their unknown isozyme through agarose gel electrophoresis. This module provides an engaging format for teaching protein biochemistry, with the flexibility to allow an instructor to modify it for their particular curriculum. PMID:21567837

  6. [Nervous regulation of glycogen concentration and the lactate dehydrogenase isoenzyme spectrum in the diaphragm of rats].

    PubMed

    Iakovlev, V F

    1981-01-01

    Content of glycogen, activity of lactate dehydrogenase (LDH) and its isoenzyme spectrum were studied in two cases of partial diaphragm denervation as well as in electro-stimulation of separate phrenic nerve branches. Dissimilar postdenervational alterations were observed in the content of glycogen and in the isozyme spectrum of LDH, which depended on the type of partial denervation. Stimulation of individual branches of the phrenic nerve showed that they separately affected the synthesis and consumption of glycogen. The data obtained suggest the nervous regulation of glycogensynthetic processes in muscle tissue. PMID:7467206

  7. Multiple aldehyde reductases of human brain.

    PubMed

    Hoffman, P L; Wermuth, B; von Wartburg, J P

    1980-01-01

    Human brain contains four forms of aldehyde reducing enzymes. One major activity, designated AR3, has properties indicating its identity with the NADPH-dependent aldehyde reductase, EC 1.1.1.2. The other major form of human brain enzyme, AR1, which is also NADPH-dependent, reduces both aldehyde and ketone-containing substrates, including vitamin K3 (menadione) and daunorubicin, a cancer chemotherapeutic agent. This enzyme is very sensitive to inhibition by the flavonoids quercitrin and quercetine, and may be analogous to a daunorubicin reductase previously described in liver of other species. One minor form of human brain aldehyde reductase, AR2, demonstrates substrate specificity and inhibitor sensitivity which suggest its similarity to aldose reductases found in lens and other tissues of many species. This enzyme, which can also use NADH as cofactor to some extent, is the most active in reducing the aldehyde derivatives of the biogenic amines. The fourth human brain enzyme ("SSA reductase") differs from the other forms in its ability to use NADH as well as or better than NADPH as cofactor, and in its molecular weight, which is nearly twice that of the other forms. It is quite specific for succinic semialdehyde (SSA) as substrate, and was found to be significantly inhibited only by quercetine and quercitrin. AR3 can also reduce SSA, and both enzymes may contribute to the production of gamma-hydroxybutyric acid in vivo. These results indicate that the human brain aldehyde reductases can play relatively specific physiologic roles. PMID:7424738

  8. Alcohol dehydrogenases from olive (Olea europaea) fruit.

    PubMed

    Salas, J J; Sánchez, J

    1998-05-01

    Alcohol dehydrogenase activity was detected in extracts from the pericarp tissues of developing olive fruits using hexanal as the substrate. Total activity in the crude extract was 20-fold higher with NADPH than with NADH. Three discrete enzymes were resolved by means of a purification protocol involving ammonium sulfate fractionation followed by ion-exchange and affinity chromatography. One of the enzymes was NAD-dependent and displayed a high K(m) for hexanal (K(m) = 2.1 mM). Two NADP-dependent alcohol dehydrogenases were resolved, one showing a high K(m) for hexanal (K(m) = 1.9 mM) and the second with a lower K(m) for the same substrate (K(m) = 0.04 mM). The three enzymes have been partially purified and their kinetic parameters and specificities for various aldehydes determined. The involvement of these enzymes in the biogenesis of six carbon alcohols constituent of the aroma of olive oil is discussed. PMID:9621451

  9. Evolution of the amylase isozymes in the Drosophila melanogaster species subgroup.

    PubMed

    Matsuo, Y; Inomata, N; Yamazaki, T

    1999-10-01

    The relationship between the net charge of molecules and their mobility on electrophoresis was analyzed for Drosophila alpha-amylases. Most of the differences in electrophoretic mobility, 98.2%, can be explained by the charge state. Therefore five reference amino acid sites, which are informative residues for charge differences among amylase isozymes, were considered for the evolution of the isozymes in Drosophila melanogaster. The amylase isozymes in D. melanogaster can be classified into three groups, I (AMY1, AMY2, and AMY3-A), II (AMY3-B and AMY4), and III (AMY5, AMY6-A, and AMY6-B), based on the differences in the reference sites. The most primitive amylase in D. melanogaster was found to belong to Group I, most likely the AMY2 isozyme. Groups II and III could have been derived from Group I. These results were confirmed by the analysis of 38 amino acid sites with charge differences in Drosophila. PMID:10626037

  10. An efficient strategy to enhance binding affinity and specificity of a known isozyme inhibitor.

    PubMed

    Jee, Joo-Eun; Lim, Jaehong; Ong, Yong Siang; Oon, Jessica; Gao, Liqian; Choi, Hak Soo; Lee, Su Seong

    2016-07-12

    The binding profile of a known inhibitor, benzenesulfonamide, against a family of carbonic anhydrase isozymes was efficiently enhanced via high-throughput screening of customized combinatorial one-bead-one-compound peptide libraries modified with the inhibitor molecule. The screening of the conjugate libraries recognized subtle variations in the microenvironments of the target enzyme and thus facilitated the identification of short peptide sequences that bind selectively to a close proximity of the active site. The identified peptide portions contributed significantly to the overall binding of the conjugate peptides with greatly enhanced affinity as well as improved specificity towards the target isozyme. The interactions between the inhibitors and the isozymes were validated by surface plasmon resonance (SPR), pull-down assay and enzymatic activity measurement. This high-throughput approach proved useful and efficient to enhance the binding profile of known inhibitors and may apply to developing effective inhibitors for a wide range of isozyme families. PMID:27339902

  11. Gel Separation of Isozymes To Study Relatedness of Common Bean Cultivars from ARound the World.

    ERIC Educational Resources Information Center

    Hammond, Paul; Oxley, Mary; Ealing, Ben

    2002-01-01

    Explains a three week laboratory experiment on the gel separation of peroxidase, which is the most well-known isozyme, from beans. Includes suggestions on the laboratory management. (Contains 13 references.) (YDS)

  12. Identification and expression of a novel carbonic anhydrase isozyme in the pufferfish Takifugu vermicularis.

    PubMed

    Sumi, Kanij Rukshana; Nou, Ill-Sup; Kho, Kang Hee

    2016-08-22

    Carbonic anhydrase (CA) is a key element for maintaining acid base balance in fish. In our present experiment, novel CA isozymes were identified from the pear puffer (Takifugu vermicularis). Based on the high homology of two predicted CA sequences of the tiger puffer (Takifugu rubripes), a 1715bp novel cDNA was obtained from T. vermicularis. The open reading frame showed a complete coding sequence of 552bp with a deduced peptide sequence of 183 amino acids that exhibited highest (97%) identity with pufferfish putative CA III and CA IV-like sequences. In addition, this translated protein sequence showed 36-37% identity with zebrafish CA IV-like, CA XVa, CA XVb, and CA XVc proteins. Phylogenetic analysis revealed that the pufferfish novel protein (pCAn) was a membrane-bound CA protein. Alignment of multiple CA sequences illustrated that most of the putative active site residues of the pCAn isozyme were situated at highly conserved regions of the CA sequences. Examination of motif distribution suggested that the pCAn isozyme was very similar to the puffer predicted CA IV-like isozyme. Reverse transcription-polymerase chain reaction (PCR) analysis showed highly differential expression in the brain, gills, kidney, and muscle, whereas CA mRNA expression was almost absent in heart, liver, and intestine. Quantitative PCR expression of CA mRNA abundance suggested several-fold higher expression of pCAn isozymes in the gills compared to other tissues tested. Our results suggest that the pCAn isozyme might be related to CA IV-like isozymes. Further functional studies are needed to investigate the function of the pCAn isozyme in T. vermicularis. PMID:27188255

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

    PubMed Central

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

    2011-01-01

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

  14. First comparative phenetic studies of Argentinean species of Acacia (Fabaceae), using morphometric, isozymal, and RAPD approaches.

    PubMed

    Casiva, Paola V; Saidman, Beatriz O; Vilardi, Juan C; Cialdella, Ana M

    2002-05-01

    Morphological and genetic diversity among Acacia aroma, A. macracantha, A. caven, and A. furcatispina were studied with morphometric, isozymal, and RAPD approaches. The analysis of seven isozyme systems revealed 21 loci, and RAPD analysis showed 34 loci. Most of these loci allowed us to differentiate the species, with the exception of A. aroma and A. macracantha, the two most similar species. The levels of genetic variability estimated by isozymes were higher than those obtained from RAPD analyses. Morphometric characters showed highly significant differences among the species, although A. aroma and A. macracantha are differentiated only by thorn length. The phenogram obtained from isozyme data is consistent with morphological data. The RAPD phenogram based on allelic frequencies showed agreement with morphological and isozymal approaches only at the intraspecific levels, while the RAPD phenogram based on Nei and Li's similarity measures agreed with the phenograms constructed from isozyme and morphological data. High similarities and high indirect gene flow were found between A. aroma and A. macracantha, results that call the relationship between them into question. PMID:21665685

  15. Purification of homologous protein carboxyl methyltransferase isozymes from human and bovine erythrocytes

    SciTech Connect

    Gilbert, J.M.; Fowler, A.; Bleibaum, J.; Clarke, S.

    1988-07-12

    The authors have purified the two major isozymes of the L-isoaspartyl/D-aspartyl protein methyltransferase from both human and bovine erythrocytes. These four enzymes all have polypeptide molecular weights of approximately 26,500 and appear to be monomers in solution. Each of these enzymes cross-reacts with antibodies directed against protein carboxyl methyltransferase I from bovine brain. Their structures also appear to be similar when analyzed by dodecyl sulfate gel electrophoresis for the large fragments produced by digestion with Staphylococcus aureus protease V8 or when analyzed by high-performance liquid chromatography (HPLC) for tryptic peptides. The structural relatedness of these enzymes was confirmed by sequence analysis of a total of 433 residues in 32 tryptic fragments of the human erythrocyte isozymes I and II and of the bovine erythrocyte isozyme II. They found sequence identity or probable identity in 111 out of 112 residues when they compared the human isozymes I and II and identities in 127 out of 134 residues when the human and bovine isozymes II were compared. These results suggest that the erythrocyte isozymes from both organisms may have nearly identical structures and confirm the similarities in the function of these methyltransferases that have been previously demonstrated.

  16. Isozymes of antioxidative enzymes during ripening and storage of ber ( Ziziphus mauritiana Lamk.).

    PubMed

    Kumar, Sunil; Yadav, Praduman; Jain, Veena; Malhotra, Sarla P

    2014-02-01

    Isozyme profile of antioxidative enzymes viz. superoxide dismutase (SOD), peroxidase (POX), catalase (CAT) and ascorbate peroxidase (APX) was studied during ripening and storage of two cultivars of ber fruit (Ziziphus mauritiana Lamk.) differing in their shelf-lives viz. Umran (shelf-life, 8-9 d) and Kaithali (shelf-life, 4-5 d). The profile revealed that Umran variety exhibited three bands each of SOD and POX while in Kaithali, these enzymes had two isoenzymes throughout ripening. CAT and APX, however, showed two isozymes each during ripening of both the varieties and the pattern remained the same at all the stages of ripening except at the initial stage i.e immature green stage where single CAT isozyme was visible. During storage, one extra band each of SOD and POX present only in Umran got disappeared at later stages of storage, whereas in Kaithali, the pattern remained unchanged. Also, there was no change in the pattern of CAT and APX isozymes during storage of both the varieties. One isozyme of CAT could be considered as ripening related while one isozyme each of SOD and POX could be related to higher shelf life of fruits. PMID:24493891

  17. Evolution of the functional properties of pyruvate kinase isozymes: pyruvate kinase L from Rana pipiens.

    PubMed

    Fournier, P; Guderley, H

    1986-01-01

    The regulatory properties of type L pyruvate kinase from Rana pipiens are intermediate between those of the mammalian K and L isozymes. As with mammalian type L, the levels of the frog isozyme are affected by the animal's nutritional state. The mammalian and amphibian isozymes show similar sensitivities to fructose 1,6-bisphosphate activation and amino acid inhibition. By contrast, the frog L isozyme shares several properties of the K class: i.e. irreversible inactivation by oxidized glutathione and lack of response to a cyclic AMP stimulated phosphorylation. Furthermore, as for some mammalian K isozymes, frog type L shows a high PEP affinity and a low cooperativity of PEP binding. Insofar as the properties of this present day enzyme reflect those of its counterpart in the amphibian ancestor of higher vertebrates, our results suggest that at its first expression, the type L resembled the type K. Many important regulatory properties of the L isozyme, especially the sensitivity to phosphorylation, were acquired more recently perhaps in association with an increased importance of constant blood glucose. PMID:3489743

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

    PubMed

    Moon, Jaewoong; Liu, Z Lewis

    2015-04-01

    The aldehyde reductase gene ARI1 is a recently characterized member of an intermediate subfamily within the short-chain dehydrogenase/reductase (SDR) superfamily that clarified mechanisms of in situ detoxification of 2-furaldehyde and 5-hydroxymethyl-2-furaldehyde by Saccharomyces cerevisiae. Uncharacterized open reading frames (ORFs) are common among tolerant candidate genes identified for lignocellulose-to-advanced biofuels conversion. This study presents partially purified proteins of two ORFs, YDR541C and YGL039W, and direct enzyme assay evidence against aldehyde-inhibitory compounds commonly encountered during lignocellulosic biomass fermentation processes. Each of the partially purified proteins encoded by these ORFs showed a molecular mass of approximately 38 kDa, similar to Ari1p, a protein encoded by aldehyde reductase gene. Both proteins demonstrated strong aldehyde reduction activities toward 14 aldehyde substrates, with high levels of reduction activity for Ydr541cp toward both aromatic and aliphatic aldehydes. While Ydr541cp was observed to have a significantly higher specific enzyme activity at 20 U/mg using co-factor NADPH, Ygl039wp displayed a NADH preference at 25 U/mg in reduction of butylaldehyde. Amino acid sequence analysis identified a characteristic catalytic triad, Ser, Tyr and Lys; a conserved catalytic motif of Tyr-X-X-X-Lys; and a cofactor-binding sequence motif, Gly-X-X-Gly-X-X-Ala, near the N-terminus that are shared by Ydr541cp, Ygl039wp, Yol151wp/GRE2 and Ari1p. Findings of aldehyde reductase genes contribute to the yeast gene annotation and aids development of the next-generation biocatalyst for advanced biofuels production. PMID:25656103

  19. Isolation and characterization of two cDNA clones of anaerobically induced lactate dehydrogenase from barley roots

    SciTech Connect

    Hondred, D.; Hanson, A.D. )

    1990-05-01

    In barley roots during hypoxia, five lactate dehydrogenase (LDH) isozymes accumulate with a concomitant increase in enzyme activity ({approximately}20-fold). These isozymes are thought to be tetramers resulting from the random association of the products of two Ldh loci. To investigate this system, cDNA clones of LDH have been isolated from a {lambda}gt11 library using antiserum raised against barley LDH purified {approximately}3,000-fold and using nucleic acid probes synthesized by the polymerase chain reaction. Two cDNA clones were obtained (1,305 and 1,166 bp). The deduced amino acid sequences of the two barley LDHs are 96% identical to each other, and 50% and 40% identical to vertebrate and bacterial LDHs, respectively. Northern blots identified a single mRNA band ({approximately}1.5 kb) whose level rose 8-fold during hypoxia.

  20. Differential effects of polyamine on the cytosolic and mitochondrial NADP-isocitrate dehydrogenases.

    PubMed

    Murakami, Keiko; Haneda, Miyako; Iwata, Shouko; Yoshino, Masataka

    2012-01-01

    Two isozymes of NADP-dependent isocitrate dehydrogenases (EC 1.1.1.42) exist in mammalian tissues: mitochondrial (ICD1) and cytosolic (ICD2). Effects of polyamines such as spermine, spermidine, and putrescine on the cytosolic and mitochondrial NADP-isocitrate dehydrogenases were analyzed kinetically. Spermine activated ICD2, the cytosolic NADP-isocitrate dehydrogenase from rat liver with the increase in the maximal velocity and the decrease in the affinity for the substrates isocitrate and NADP. The activating action of spermine can be explained by "the uncompetitive effect," and the dissociation constant of spermine for the enzyme-substrate complex was determined to be 1.68 mM. Spermidine and putrescine showed little or no effect. ICD1, the mitochondrial form of NADP-isocitrate dehydrogenase from rat and porcine heart was inhibited by spermine effectively, and by spermidine and putrescine to a lesser extent. Spermine inhibited the enzyme competitively with respect to NADP, and noncompetitively with respect to isocitrate. K(i) value of the enzyme for spermine was 1.3 mM. These results suggest that activation by spermine of cytosolic NADP-isocitrate dehydrogenase can enhance the antioxidant activity by regeneration of GSH, and further is responsible for the stimulation of lipid biosynthesis in cytosol. Spermine may contribute to NADPH supply by enhancing transhydrogenase (EC1.6.1.2) activity through the spermine-dependent activation of Ca(2+) -incorporation to mitochondria. PMID:22674798

  1. Peroxisomal NADP-isocitrate dehydrogenase is required for Arabidopsis stomatal movement.

    PubMed

    Leterrier, Marina; Barroso, Juan B; Valderrama, Raquel; Begara-Morales, Juan C; Sánchez-Calvo, Beatriz; Chaki, Mounira; Luque, Francisco; Viñegla, Benjamin; Palma, José M; Corpas, Francisco J

    2016-03-01

    Peroxisomes are subcellular organelles characterized by a simple morphological structure but have a complex biochemical machinery involved in signaling processes through molecules such as hydrogen peroxide (H2O2) and nitric oxide (NO). Nicotinamide adenine dinucleotide phosphate (NADPH) is an essential component in cell redox homeostasis, and its regeneration is critical for reductive biosynthesis and detoxification pathways. Plants have several NADPH-generating dehydrogenases, with NADP-isocitrate dehydrogenase (NADP-ICDH) being one of these enzymes. Arabidopsis contains three genes that encode for cytosolic, mitochondrial/chloroplastic, and peroxisomal NADP-ICDH isozymes although the specific function of each of these remains largely unknown. Using two T-DNA insertion lines of the peroxisomal NADP-ICDH designated as picdh-1 and picdh-2, the data show that the peroxisomal NADP-ICDH is involved in stomatal movements, suggesting that peroxisomes are a new element in the signaling network of guard cells. PMID:25894616

  2. Chemoenzymatic Fc Glycosylation via Engineered Aldehyde Tags

    PubMed Central

    2014-01-01

    Glycoproteins with chemically defined glycosylation sites and structures are important biopharmaceutical targets and critical tools for glycobiology. One approach toward constructing such molecules involves chemical glycosylation of aldehyde-tagged proteins. Here, we report the installation of a genetically encoded aldehyde tag at the internal glycosylation site of the crystallizable fragment (Fc) of IgG1. We replaced the natural Fc N-glycosylation sequon with a five amino-acid sequence that was efficiently converted by recombinant formylglycine generating enzyme in vitro, thereby introducing aldehyde groups for subsequent chemical elaboration. Oxime-linked glycoconjugates were synthesized by conjugating aminooxy N-acetylglucosamine to the modified Fc followed by enzymatic transfer of complex N-glycans from corresponding glycan oxazolines by an EndoS-derived glycosynthase. In this manner we generated specific Fc glycoforms without relying on natural protein glycosylation machineries. PMID:24702330

  3. Intercalation of Aldehydes into Vanadyl Phosphate

    NASA Astrophysics Data System (ADS)

    Melánová, Klára; Beneš, Ludvík.; Zima, Vítězslav; Votinský, Jiří

    2001-02-01

    Intercalates of VOPO4 with several aliphatic aldehydes, benzaldehyde, and 4-methylbenzaldehyde were prepared and characterized by thermogravimetric analysis, X-ray diffractometry, and IR and UV-vis spectroscopies. Aliphatic aldehyde intercalates are unstable and the guests undergo aldol condensation and oxidation. The arrangement of the guest molecules in the interlayer space of the host is discussed. A part of aliphatic aldehydes is anchored to the host layers by coordination of their carbonyl oxygen to the vanadium atom; the rest is probably bonded by weak van der Waals forces. In the benzaldehyde and 4-methylbenzaldehyde intercalates, all guest molecules are coordinated to the vanadium atoms with their benzene rings perpendicular to the sheets of the host.

  4. Separation of dehydrogenases on polyaminomethylstyrene.

    PubMed

    Schöpp, W; Meinert, S; Thyfronitou, J; Aurich, H

    1975-01-29

    The binding of dehydrogenases, especially alcohol dehydrogenase, and other proteins to several ion exchangers and hydrophobic polymers was investigated. Quantitative parameters for the stability of the polymer-protein complexes (obtained form double reciprocal plots) indicate a high but different affinity of many proteins for polyaminomethylstyrene. The chromatography of a mixture of five dehydrogenases and human serum albumin on polyaminomethylstyrene is described. PMID:237012

  5. The selectivity of beauveriolide derivatives in inhibition toward the two isozymes of acyl-CoA: cholesterol acyltransferase.

    PubMed

    Ohshiro, Taichi; Matsuda, Daisuke; Nagai, Kenichiro; Doi, Takayuki; Sunazuka, Toshiaki; Takahashi, Takashi; Rudel, Lawrence Lee; Omura, Satoshi; Tomoda, Hiroshi

    2009-04-01

    The selectivity of synthetic beauveriolide derivatives in inhibition toward the two isozymes of acyl-CoA : cholesterol acyltrasferase (ACAT), ACAT1 and ACAT2, was studied in cell-based assays using ACAT1- or ACAT2-expressing Chinese hamster ovary (CHO) cells. NBV274, 285 and 300 showed ACAT1 selective inhibition similar to that of natural beauveriolides I and III, NBV345 inhibited both isozymes with similar potency, but NBV281, 331 and 249 were found to selectively inhibit the ACAT2 isozyme. The structure-activity relationships indicated that a subtle structural difference in beauveriolide derivatives can affect the selectivity of inhibition of the ACAT isozymes. PMID:19336931

  6. Evans-Tishchenko coupling of heteroaryl aldehydes.

    PubMed

    Dorgan, Philip D; Durrani, Jamie; Cases-Thomas, Manuel J; Hulme, Alison N

    2010-11-01

    The low-temperature Evans-Tishchenko coupling of a range of functionalized heteroaryl aldehydes with β-hydroxy ketones in the presence of a Sm(III) catalyst has been achieved with high yields (90-99%) and good to excellent diastereoselectivity (90:10 → 95:5 dr). However, at room temperature a retro-aldol aldol-Tishchenko reaction was found to compete with the desired Evans-Tishchenko reaction. Identification of these byproducts has allowed the corresponding aldol-Tishchenko reaction to be optimized for several heteroaryl aldehydes. PMID:20929205

  7. In Silico Analysis of Arabidopsis thaliana Peroxisomal 6-Phosphogluconate Dehydrogenase

    PubMed Central

    Fernández-Fernández, Álvaro D.; Corpas, Francisco J.

    2016-01-01

    NADPH, whose regeneration is critical for reductive biosynthesis and detoxification pathways, is an essential component in cell redox homeostasis. Peroxisomes are subcellular organelles with a complex biochemical machinery involved in signaling and stress processes by molecules such as hydrogen peroxide (H2O2) and nitric oxide (NO). NADPH is required by several peroxisomal enzymes involved in β-oxidation, NO, and glutathione (GSH) generation. Plants have various NADPH-generating dehydrogenases, one of which is 6-phosphogluconate dehydrogenase (6PGDH). Arabidopsis contains three 6PGDH genes that probably are encoded for cytosolic, chloroplastic/mitochondrial, and peroxisomal isozymes, although their specific functions remain largely unknown. This study focuses on the in silico analysis of the biochemical characteristics and gene expression of peroxisomal 6PGDH (p6PGDH) with the aim of understanding its potential function in the peroxisomal NADPH-recycling system. The data show that a group of plant 6PGDHs contains an archetypal type 1 peroxisomal targeting signal (PTS), while in silico gene expression analysis using affymetrix microarray data suggests that Arabidopsis p6PGDH appears to be mainly involved in xenobiotic response, growth, and developmental processes. PMID:27034898

  8. Distribution of Pyruvate Dehydrogenase Complex Activities between Chloroplasts and Mitochondria from Leaves of Different Species.

    PubMed Central

    Lernmark, U.; Gardestrom, P.

    1994-01-01

    Protoplasts from barley (Hordeum vulgare), pea (Pisum sativum), wheat (Triticum aestivum), and spinach (Spinacia oleracea) leaves were fractionated into chloroplast- and mitochondrion-enriched fractions. Pyruvate dehydrogenase complex capacities in mitochondria (mtPDC) and chloroplasts (cpPDC) were measured in appropriate fractions under conditions optimal for each isozyme. The total cellular capacity of PDC was similar in barley and pea but about 50% lower in wheat and spinach. In pea a distribution of 87% mtPDC and 13% cpPDC was found on a cellular basis. In barley, wheat, and spinach the subcellular distribution was the opposite, with about 15% mtPDC and 85% cpPDC. cpPDC activity was constant at about 0.1 nmol cell-1 h-1 in cells from different regions along the developing barley leaf and showed no correlation with developmental patterns of photosynthetic parameters, such as increasing Chl and NADP-glyceraldehyde-3-phosphate dehydrogenase activity. Similarly, the capacity of the mitochondrial isoform did not change during barley leaf development and had a developmental pattern similar to that of citrate synthase and fumarase. Differences in subcellular distribution of PDCs in barley and pea are proposed to be due to differences in regulation, not to changes in isozyme proportions during leaf development or to species-specific differences in phosphorylation state of mtPDC after organelle separation. PMID:12232437

  9. Characterization of alcohol dehydrogenase 1 and 3 from Neurospora crassa FGSC2489.

    PubMed

    Park, Yong-Cheol; San, Ka-Yiu; Bennett, George N

    2007-08-01

    Alcohol dehydrogenase (ADH) is a key enzyme in the production and utilization of alcohols. Some also catalyze the formation of carboxylate esters from alcohols and aldehydes. The ADH1 and ADH3 genes of Neurospora crassa FGSC2489 were cloned and expressed in recombinant Escherichia coli to investigate their alcohol dehydrogenation and carboxylate ester formation abilities. Homology analysis and sequence alignment of amino acid sequence indicated that ADH1 and ADH3 of N. crassa contained a zinc-binding consensus sequence and a NAD(+)-binding motif and showed 54-75% identity with fungi ADHs. N. crassa ADH1 was expressed in E. coli to give a specific activity of 289 +/- 9 mU/mg using ethanol and NAD(+) as substrate and cofactor, respectively. Corresponding experiments on the expression and activity of ADH3 gave 4 mU/mg of specific activity. N. crassa ADH1 preferred primary alcohols containing C3-C8 carbons to secondary alcohols such as 2-propanol and 2-butanol. N. crassa ADH1 possessed 5.3 mU/mg of specific carboxylate ester-forming activity accumulating 0.4 mM of ethyl acetate in 18 h. Substrate specificity of various linear alcohols and aldehydes indicated that short chain-length alcohols and aldehydes were good substrates for carboxylate ester production. N. crassa ADH1 was a primary alcohol dehydrogenase using cofactor NAD(+) preferably and possessed carboxylate ester-forming activity with short chain alcohols and aldehydes. PMID:17516063

  10. Crystallographic and spectroscopic snapshots reveal a dehydrogenase in action

    SciTech Connect

    Huo, Lu; Davis, Ian; Liu, Fange; Andi, Babak; Esaki, Shingo; Iwaki, Hiroaki; Hasegawa, Yoshie; Orville, Allen M.; Liu, Aimin

    2015-01-07

    Aldehydes are ubiquitous intermediates in metabolic pathways and their innate reactivity can often make them quite unstable. There are several aldehydic intermediates in the metabolic pathway for tryptophan degradation that can decay into neuroactive compounds that have been associated with numerous neurological diseases. An enzyme of this pathway, 2-aminomuconate-6-semialdehyde dehydrogenase, is responsible for ‘disarming’ the final aldehydic intermediate. Here we show the crystal structures of a bacterial analogue enzyme in five catalytically relevant forms: resting state, one binary and two ternary complexes, and a covalent, thioacyl intermediate. We also report the crystal structures of a tetrahedral, thiohemiacetal intermediate, a thioacyl intermediate and an NAD+-bound complex from an active site mutant. These covalent intermediates are characterized by single-crystal and solution-state electronic absorption spectroscopy. The crystal structures reveal that the substrate undergoes an E/Z isomerization at the enzyme active site before an sp3-to-sp2 transition during enzyme-mediated oxidation.

  11. Crystallographic and spectroscopic snapshots reveal a dehydrogenase in action

    DOE PAGESBeta

    Huo, Lu; Davis, Ian; Liu, Fange; Andi, Babak; Esaki, Shingo; Iwaki, Hiroaki; Hasegawa, Yoshie; Orville, Allen M.; Liu, Aimin

    2015-01-07

    Aldehydes are ubiquitous intermediates in metabolic pathways and their innate reactivity can often make them quite unstable. There are several aldehydic intermediates in the metabolic pathway for tryptophan degradation that can decay into neuroactive compounds that have been associated with numerous neurological diseases. An enzyme of this pathway, 2-aminomuconate-6-semialdehyde dehydrogenase, is responsible for ‘disarming’ the final aldehydic intermediate. Here we show the crystal structures of a bacterial analogue enzyme in five catalytically relevant forms: resting state, one binary and two ternary complexes, and a covalent, thioacyl intermediate. We also report the crystal structures of a tetrahedral, thiohemiacetal intermediate, a thioacylmore » intermediate and an NAD+-bound complex from an active site mutant. These covalent intermediates are characterized by single-crystal and solution-state electronic absorption spectroscopy. The crystal structures reveal that the substrate undergoes an E/Z isomerization at the enzyme active site before an sp3-to-sp2 transition during enzyme-mediated oxidation.« less

  12. Crystallographic and spectroscopic snapshots reveal a dehydrogenase in action

    PubMed Central

    Huo, Lu; Davis, Ian; Liu, Fange; Andi, Babak; Esaki, Shingo; Iwaki, Hiroaki; Hasegawa, Yoshie; Orville, Allen M.; Liu, Aimin

    2015-01-01

    Aldehydes are ubiquitous intermediates in metabolic pathways and their innate reactivity can often make them quite unstable. There are several aldehydic intermediates in the metabolic pathway for tryptophan degradation that can decay into neuroactive compounds that have been associated with numerous neurological diseases. An enzyme of this pathway, 2-aminomuconate-6-semialdehyde dehydrogenase, is responsible for ‘disarming’ the final aldehydic intermediate. Here we show the crystal structures of a bacterial analogue enzyme in five catalytically relevant forms: resting state, one binary and two ternary complexes, and a covalent, thioacyl intermediate. We also report the crystal structures of a tetrahedral, thiohemiacetal intermediate, a thioacyl intermediate and an NAD+-bound complex from an active site mutant. These covalent intermediates are characterized by single-crystal and solution-state electronic absorption spectroscopy. The crystal structures reveal that the substrate undergoes an E/Z isomerization at the enzyme active site before an sp3-to-sp2 transition during enzyme-mediated oxidation. PMID:25565451

  13. Na,K-ATPase Isozymes in Colorectal Cancer and Liver Metastases

    PubMed Central

    Baker Bechmann, Marc; Rotoli, Deborah; Morales, Manuel; Maeso, María del Carmen; García, María del Pino; Ávila, Julio; Mobasheri, Ali; Martín-Vasallo, Pablo

    2016-01-01

    The goal of this study was to define Na,K-ATPase α and β subunit isoform expression and isozyme composition in colorectal cancer cells and liver metastases. The α1, α3, and β1 isoforms were the most highly expressed in tumor cells and metastases; in the plasma membrane of non-neoplastic cells and mainly in a cytoplasmic location in tumor cells. α1β1 and α3β1 isozymes found in tumor and metastatic cells exhibit the highest and lowest Na+ affinity respectively and the highest K+ affinity. Mesenchymal cell isozymes possess an intermediate Na+ affinity and a low K+ affinity. In cancer, these ions are likely to favor optimal conditions for the function of nuclear enzymes involved in mitosis, especially a high intra-nuclear K+ concentration. A major and striking finding of this study was that in liver, metastasized CRC cells express the α3β1 isozyme. Thus, the α3β1 isozyme could potentially serve as a novel exploratory biomarker of CRC metastatic cells in liver. PMID:26858653

  14. Production and characterization of recombinant lignin peroxidase isozyme H2 from Phanerochaete chrysosporium using recombinant baculovirus.

    PubMed

    Johnson, T M; Pease, E A; Li, J K; Tien, M

    1992-08-01

    Recombinant Phanerochaete chrysosporium lignin peroxidase isozyme H2 (pI 4.4) was produced in insect cells infected with a genetically engineered baculovirus containing a copy of the cDNA clone lambda ML-6. The recombinant enzyme was purified to near homogeneity and is capable of oxidizing veratryl alcohol, iodide, and, to a lesser extent, guaiacol. The Km of the recombinant enzyme for veratryl alcohol and H2O2 is similar to that of the fungal enzyme. The guaiacol oxidation activity or any other activity is not dependent upon Mn2+. The purified recombinant peroxidase is glycosylated with N-linked carbohydrate(s). The recombinant lignin peroxidase eluted from an anion exchange resin similar to that of native isozyme H1 rather than H2. However, the pI of the recombinant enzymes is different from both H1 and H2 isozymes. Further characterization of native isozymes H1 and H2 from the fungal cultures revealed identical N-terminus residues. This indicates that isozymes H1 and H2 differ in post-translational modification. PMID:1632652

  15. AMP deaminase histochemical activity and immunofluorescent isozyme localization in rat skeletal muscle

    NASA Technical Reports Server (NTRS)

    Thompson, J. L.; Sabina, R. L.; Ogasawara, N.; Riley, D. A.

    1992-01-01

    The cellular distribution of AMP deaminase (AMPda) isozymes was documented for rat soleus and plantaris muscles, utilizing immunofluorescence microscopy and immunoprecipitation methods. AMPda is a ubiquitous enzyme existing as three distinct isozymes, A, B and C, which were initially purified from skeletal muscle, liver (and kidney), and heart, respectively. AMPda-A is primarily concentrated subsarcolemmally and intermyofibrillarly within muscle cells, while isozymes B and C are concentrated within non-myofiber elements of muscle tissue. AMPda-B is principally associated with connective tissues surrounding neural elements and the muscle spindle capsule, and AMPda-C is predominantly associated with circulatory elements, such as arterial and venous walls, capillary endothelium, and red blood cells. These specific localizations, combined with documented differences in kinetic properties, suggest multiple functional roles for the AMPda isozymes or temporal segregation of similar AMPda functions. Linkage of the AMPda substrate with adenosine production pathways at the AMP level and the localization of isozyme-C in vascular tissue suggest a regulatory role in the microcirculation.

  16. The First Mammalian Aldehyde Oxidase Crystal Structure

    PubMed Central

    Coelho, Catarina; Mahro, Martin; Trincão, José; Carvalho, Alexandra T. P.; Ramos, Maria João; Terao, Mineko; Garattini, Enrico; Leimkühler, Silke; Romão, Maria João

    2012-01-01

    Aldehyde oxidases (AOXs) are homodimeric proteins belonging to the xanthine oxidase family of molybdenum-containing enzymes. Each 150-kDa monomer contains a FAD redox cofactor, two spectroscopically distinct [2Fe-2S] clusters, and a molybdenum cofactor located within the protein active site. AOXs are characterized by broad range substrate specificity, oxidizing different aldehydes and aromatic N-heterocycles. Despite increasing recognition of its role in the metabolism of drugs and xenobiotics, the physiological function of the protein is still largely unknown. We have crystallized and solved the crystal structure of mouse liver aldehyde oxidase 3 to 2.9 Å. This is the first mammalian AOX whose structure has been solved. The structure provides important insights into the protein active center and further evidence on the catalytic differences characterizing AOX and xanthine oxidoreductase. The mouse liver aldehyde oxidase 3 three-dimensional structure combined with kinetic, mutagenesis data, molecular docking, and molecular dynamics studies make a decisive contribution to understand the molecular basis of its rather broad substrate specificity. PMID:23019336

  17. Oxidation of Aromatic Aldehydes Using Oxone

    ERIC Educational Resources Information Center

    Gandhari, Rajani; Maddukuri, Padma P.; Thottumkara, Vinod K.

    2007-01-01

    The experiment demonstrating the feasibility of using water as a solvent for organic reactions which highlights the cost and environmental benefits of its use is presented. The experiment encourages students to think in terms of the reaction mechanism of the oxidation of aldehydes knowing that potassium persulfate is the active oxidant in Oxone…

  18. Volatile aldehydes in libraries and archives

    NASA Astrophysics Data System (ADS)

    Fenech, Ann; Strlič, Matija; Kralj Cigić, Irena; Levart, Alenka; Gibson, Lorraine T.; de Bruin, Gerrit; Ntanos, Konstantinos; Kolar, Jana; Cassar, May

    2010-06-01

    Volatile aldehydes are produced during degradation of paper-based materials. This may result in their accumulation in archival and library repositories. However, no systematic study has been performed so far. In the frame of this study, passive sampling was carried out at ten locations in four libraries and archives. Despite the very variable sampling locations, no major differences were found, although air-filtered repositories were found to have lower concentrations while a non-ventilated newspaper repository exhibited the highest concentrations of volatile aldehydes (formaldehyde, acetaldehyde, furfural and hexanal). Five employees in one institution were also provided with personal passive samplers to investigate employees' exposure to volatile aldehydes. All values were lower than the presently valid exposure limits. The concentration of volatile aldehydes, acetic acid, and volatile organic compounds (VOCs) in general was also compared with that of outdoor-generated pollutants. It was evident that inside the repository and particularly inside archival boxes, the concentration of VOCs and acetic acid was much higher than the concentration of outdoor-generated pollutants, which are otherwise more routinely studied in connection with heritage materials. This indicates that further work on the pro-degradative effect of VOCs on heritage materials is necessary and that monitoring of VOCs in heritage institutions should become more widespread.

  19. Bioinformatic scaling of allosteric interactions in biomedical isozymes

    NASA Astrophysics Data System (ADS)

    Phillips, J. C.

    2016-09-01

    Allosteric (long-range) interactions can be surprisingly strong in proteins of biomedical interest. Here we use bioinformatic scaling to connect prior results on nonsteroidal anti-inflammatory drugs to promising new drugs that inhibit cancer cell metabolism. Many parallel features are apparent, which explain how even one amino acid mutation, remote from active sites, can alter medical results. The enzyme twins involved are cyclooxygenase (aspirin) and isocitrate dehydrogenase (IDH). The IDH results are accurate to 1% and are overdetermined by adjusting a single bioinformatic scaling parameter. It appears that the final stage in optimizing protein functionality may involve leveling of the hydrophobic limits of the arms of conformational hydrophilic hinges.

  20. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN...

  1. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN...

  2. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN...

  3. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN...

  4. 40 CFR 721.639 - Amine aldehyde condensate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amine aldehyde condensate. 721.639... Substances § 721.639 Amine aldehyde condensate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an amine aldehyde condensate (PMN...

  5. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Code of Federal Regulations, 2010 CFR

    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...

  6. Aldehyde Reduction by Cytochrome P450

    PubMed Central

    Amunom, Immaculate; Srivastava, Sanjay; Prough, Russell A.

    2011-01-01

    This protocol describes the procedure for measuring the relative rates of metabolism of the α,β-unsaturated aldehydes, 9-anthracene aldehyde (9-AA) and 4-hydroxy-trans-2-nonenal (4-HNE); specifically the aldehyde reduction reactions of cytochrome P450s (CYPs). These assays can be performed using either liver microsomal or other tissue fractions, spherosome preparations of recombinant CYPs, or recombinant CYPs from other sources. The method used here to study the reduction of a model α,β-unsaturated aldehyde, 9-AA, by CYPs was adapted from the assay used to investigate 9-anthracene oxidation as reported by Marini et al. (Marini et al., 2003). For experiments measuring reduction of the endogenous aldehyde, 4-HNE, the substrate was incubated with CYP in the presence of oxygen and NADPH and the metabolites were separated by High Pressure Liquid Chromatograpy (HPLC), using an adaptation of the method of Srivastava et al. (Srivastava et al., 2010). For study of 9-AA and 4-HNE reduction, the first step involves incubation of the substrate with the CYP in appropriate media, followed by quantification of metabolites through either spectrofluorimetry or analysis by HPLC coupled with a radiometric assay, respectively. Metabolite identification can be achieved by HPLC GC-mass spectrometric analysis. Inhibitors of cytochrome P450 function can be utilized to show the role of the hemoprotein or other enzymes in these reduction reactions. The reduction reactions for CYP’s were not inhibited by either anaerobiosis or inclusion of CO in the gaseous phase of the reaction mixture. These character of these reactions are similar to those reported for some cytochrome P450-catalyzed azo reduction reactions. PMID:21553396

  7. Isozyme expression of Chinese and Japanese populations of Chlamys farreri and their reciprocal hybrids

    NASA Astrophysics Data System (ADS)

    Li, Taiwu; Liu, Yan; Song, Linsheng; Sun, Xiuqin

    2005-06-01

    Chinese and Japanese population of Chlamys farreri and their reciprocal hybrids were surveyed in isozyme variability at 13 loci by polyacrytamide gel electrophoresis (PAGE). Isozyme banding patterns indicated these hybrids were diploid. Loci that were observed as being monomorphic in inbred populations of C. farreri were also found to be monomorphic in filial progeny; loci that observed to be polymorphic in parental type generations were also polymorphic in hybrid generations. Differences existed among allelic frequency of the four types of cross. Within the reciprocal hybrids the expression of malic enzyme (ME) isozyme was sufficient to distinguishing individual hybrids because of the band, Rf=0.38. However, there were no noticeable variations among all the samples to differentiate one from another. Inbreeding was likely to be the main problem in aquaculture. The introduction of new broodstock can improve the genetic diversity. Hybrid vigor has manifested to a certain extent in the present study.

  8. Comparison of the catalytic activities of three isozymes of carnitine palmitoyltransferase 1 expressed in COS7 cells.

    PubMed

    Hada, Takuya; Yamamoto, Takenori; Yamamoto, Atsushi; Ohkura, Kazuto; Yamazaki, Naoshi; Takiguchi, Yoshiharu; Shinohara, Yasuo

    2014-02-01

    The enzyme carnitine palmitoyltransferase 1 (CPT1) catalyzes the transfer of an acyl group from acyl-CoA to carnitine to form acylcarnitine, and three isozymes of it, 1a, 1b, and 1c, have been identified. Interestingly, the 1c isozyme was reported to show no enzymatic activity, but it was not clearly demonstrated whether this inactivity was due to its dysfunction or due to its poor expression. In the present study, we (a) expressed individual CPT1 isozymes in COS7 cells, (b) evaluated quantitatively their expression levels by Western blotting using the three bacterially expressed CPT1 isozymes as standards, and (c) evaluated their catalytic activities. With these experiments, we successfully demonstrated that the absence of the enzymatic activity of the 1c isozyme was due to its dysfunction. In addition, experiments on the preparation of standard CPT1 isozymes revealed that the 1c isozyme did not show the standard relationship between migration in an SDS-PAGE gel and molecular size. We further tried to determine why the 1c isozyme was inert by preparing chimeric CPT1 between 1a and 1c, but no clear conclusion could be drawn because one of the chimeric CPT1s was not sufficiently expressed. PMID:24222496

  9. Formation and control of aldehydes in alcohol fueled engines

    SciTech Connect

    Ayyasamy, R.; Nagalingam, B.; Ganesan, V.; Gopalakrishnan, K.V.; Murthy, B.S.

    1981-01-01

    Aldehyde formation and emissions from alcohol fueled engines are presented in this paper. Several chemical kinetic models on the mechanism leading to aldehyde formation have been examined to explore the appropriate control methods to reduce exhaust aldehyde emissions. Control of aldehydes in exhaust emissions by suitable alteration of engine operating parameters, by in cylinder treatment with additives like aniline and water, by external treatment like airpreheating, secondary air injection cooling water rate and exhaust treatment are examined. The concept of surface ignition for alcohol fuels is briefly presented as a long range objective for using alcohols with minimal aldehyde emissions. 27 refs.

  10. Purification and properties of the inducible coenzyme A-linked butyraldehyde dehydrogenase from Clostridium acetobutylicum.

    PubMed Central

    Palosaari, N R; Rogers, P

    1988-01-01

    The coenzyme A (CoA)-linked butyraldehyde dehydrogenase (BAD) from Clostridium acetobutylicum was characterized and purified to homogeneity. The enzyme was induced over 200-fold, coincident with a shift from an acidogenic to a solventogenic fermentation, during batch culture growth. The increase in enzyme activity was found to require new protein synthesis since induction was blocked by the addition of rifampin and antibody against the purified enzyme showed the appearance of enzyme antigen beginning at the shift of the fermentation and increasing coordinately with the increase in enzyme specific activity. The CoA-linked acetaldehyde dehydrogenase was copurified with BAD during an 89-fold purification, indicating that one enzyme accounts for the synthesis of the two aldehyde intermediates for both butanol and ethanol production. Butanol dehydrogenase activity was clearly separate from the BAD enzyme activity on TEAE cellulose. A molecular weight of 115,000 was determined for the native enzyme, and the enzyme subunit had a molecular weight of 56,000 indicating that the active form is a homodimer. Kinetic constants were determined in both the forward and reverse directions. In the reverse direction both the Vmax and the apparent affinity for butyraldehyde and caproaldehyde were significantly greater than they were for acetaldehyde, while in the forward direction, the Vmax for butyryl-CoA was fivefold that for acetyl-CoA. These and other properties of BAD indicate that this enzyme is distinctly different from other reported CoA-dependent aldehyde dehydrogenases. Images PMID:3384801

  11. Regulated Expression of Three Alcohol Dehydrogenase Genes in Barley Aleurone Layers 1

    PubMed Central

    Hanson, Andrew D.; Jacobsen, John V.; Zwar, John A.

    1984-01-01

    Three genes specify alcohol dehydrogenase (EC 1.1.1.1.; ADH) enzymes in barley (Hordeum vulgare L.) (Adh 1, Adh 2, and Adh 3). Their polypeptide products (ADH 1, ADH 2, ADH 3) dimerize to give a total of six ADH isozymes which can be resolved by native gel electrophoresis and stained for enzyme activity. Under fully aerobic conditions, aleurone layers of cv Himalaya had a high titer of a single isozyme, the homodimer containing ADH 1 monomers. This isozyme was accumulated by the aleurone tissue during the later part of seed development, and survived seed drying and rehydration. The five other possible ADH isozymes were induced by O2 deficit. The staining of these five isozymes on electrophoretic gels increased progressively in intensity as O2 levels were reduced below 5%, and were most intense at 0% O2. In vivo35S labeling and specific immunoprecipitation of ADH peptides, followed by isoelectric focusing of the ADH peptides in the presence of 8 molar urea (urea-IEF) demonstrated the following. (a) Aleurone layers incubated in air synthesized ADH 1 and a trace of ADH 2; immature layers from developing seeds behaved similarly. (b) At 5% O2, synthesis of ADH 2 increased and ADH 3 appeared. (c) At 2% and 0% O2, the synthesis of all three ADH peptides increased markedly. Cell-free translation of RNA isolated from aleurone layers, followed by immunoprecipitation and urea-IEF of in vitro synthesized ADH peptides, showed that levels of mRNA for all three ADH peptides rose sharply during 1 day of O2 deprivation. Northern hybridizations with a maize Adh 2 cDNA clone established that the clone hybridized with barley mRNA comparable in size to maize Adh 2 mRNA, and that the level of this barley mRNA increased 15- to 20-fold after 1 day at 5% or 2% O2, and about 100-fold after 1 day at 0% O2. We conclude that in aleurone layers, expression of the three barley Adh genes is maximal in the absence of O2, that regulation of mRNA level is likely to be a major controlling factor, and

  12. Affinity chromatography of nicotinamide–adenine dinucleotide-linked dehydrogenases on immobilized derivatives of the dinucleotide

    PubMed Central

    Barry, Standish; O'Carra, Pádraig

    1973-01-01

    1. Three established methods for immobilization of ligands through primary amino groups promoted little or no attachment of NAD+ through the 6-amino group of the adenine residue. Two of these methods (coupling to CNBr-activated agarose and to carbodi-imide-activated carboxylated agarose derivatives) resulted instead in attachment predominantly through the ribosyl residues. Other immobilized derivatives were prepared by azolinkage of NAD+ (probably through the 8 position of the adenine residue) to a number of different spacer-arm–agarose derivatives. 2. The effectiveness of these derivatives in the affinity chromatography of a variety of NAD-linked dehydrogenases was investigated, applying rigorous criteria to distinguish general or non-specific adsorption effects from truly NAD-specific affinity (bio-affinity). The ribosyl-attached NAD+ derivatives displayed negligible bio-affinity for any of the NAD-linked dehydrogenases tested. The most effective azo-linked derivative displayed strong bio-affinity for glycer-aldehyde 3-phosphate dehydrogenase, weaker bio-affinity for lactate dehydrogenase and none at all for malate dehydrogenase, although these three enzymes have very similar affinities for soluble NAD+. Alcohol dehydrogenase and xanthine dehydrogenase were subject to such strong non-specific interactions with the hydrocarbon spacer-arm assembly that any specific affinity was completely eclipsed. 3. It is concluded that, in practice, the general effectiveness of a general ligand may be considerably distorted and attenuated by the nature of the immobilization linkage. However, this attenuation can result in an increase in specific effectiveness, allowing dehydrogenases to be separated from one another in a manner unlikely to be feasible if the general effectiveness of the ligand remained intact. 4. The bio-affinity of the various derivatives for lactate dehydrogenase is correlated with the known structure of the NAD+-binding site of this enzyme. Problems

  13. Cyanobacterial NADPH dehydrogenase complexes

    SciTech Connect

    Ogawa, Teruo; Mi, Hualing

    2007-07-01

    Cyanobacteria possess functionally distinct multiple NADPH dehydrogenase (NDH-1) complexes that are essential to CO2 uptake, photosystem-1 cyclic electron transport and respiration. The unique nature of cyanobacterial NDH-1 complexes is the presence of subunits involved in CO2 uptake. Other than CO2 uptake, chloroplastic NDH-1 complex has similar role as cyanobacterial NDH-1 complexes in photosystem-1 cyclic electron transport and respiration (chlororespiration). In this mini-review we focus on the structure and function of cyanobacterial NDH-1 complexes and their phylogeny. The function of chloroplastic NDH-1 complex and characteristics of plants defective in NDH-1 are also described forcomparison.

  14. Neurotoxicity of reactive aldehydes: the concept of "aldehyde load" as demonstrated by neuroprotection with hydroxylamines.

    PubMed

    Wood, Paul L; Khan, M Amin; Kulow, Sarah R; Mahmood, Siddique A; Moskal, Joseph R

    2006-06-20

    The concept of "oxidative stress" has become a mainstay in the field of neurodegeneration but has failed to differentiate critical events from epiphenomena and sequalae. Furthermore, the translation of current concepts of neurodegenerative mechanisms into effective therapeutics for neurodegenerative diseases has been meager and disappointing. A corollary of current concepts of "oxidative stress" is that of "aldehyde load". This relates to the production of reactive aldehydes that covalently modify proteins, nucleic acids, lipids and carbohydrates and activate apoptotic pathways. However, reactive aldehydes can also be generated by mechanisms other than "oxidative stress". We therefore hypothesized that agents that can chemically neutralize reactive aldehydes should demonstrate superior neuroprotective actions to those of free radical scavengers. To this end, we evaluated hydroxylamines as aldehyde-trapping agents in an in vitro model of neurodegeneration induced by the reactive aldehyde, 3-aminopropanal (3-AP), a product of polyamine oxidase metabolism of spermine and spermidine. In this model, the hydroxylamines N-benzylhydroxylamine, cyclohexylhydroxylamine and t-butylhydroxylamine were shown to protect, in a concentration-dependent manner, against 3-AP neurotoxicity. Additionally, a therapeutic window of 3 h was demonstrated for delayed administration of the hydroxylamines. In contrast, the free radical scavengers TEMPO and TEMPONE and the anti-oxidant ascorbic acid were ineffective in this model. Extending these tissue culture findings in vivo, we examined the actions of N-benzylhydroxylamine in the trimethyltin (TMT) rat model of hippocampal CA3 neurodegeneration. This model involves augmented polyamine metabolism resulting in the generation of reactive aldehydes that compromise mitochondrial integrity. In the rat TMT model, NBHA (50 mg/kg, sc, daily) provided 100% protection against neurodegeneration, as reflected by measurements of KCl-evoked glutamate

  15. Mechanistic Insights from Reaction of α-Oxiranyl-Aldehydes with Cyanobacterial Aldehyde Deformylating Oxygenase

    PubMed Central

    Das, Debasis; Ellington, Benjamin; Paul, Bishwajit; Marsh, E. Neil G.

    2014-01-01

    The biosynthesis of long-chain aliphatic hydrocarbons, which are derived from fatty acids, is widespread in Nature. The last step in this pathway involves the decarbonylation of fatty aldehydes to the corresponding alkanes or alkenes. In cyanobacteria this is catalyzed by an aldehyde deformylating oxygenase. We have investigated the mechanism of this enzyme using substrates bearing an oxirane ring adjacent to the aldehyde carbon. The enzyme catalyzed the deformylation of these substrates to produce the corresponding oxiranes. Performing the reaction in D2O allowed the facial selectivity of proton addition to be examined by 1H-NMR spectroscopy. The proton is delivered with equal probability to either face of the oxirane ring, indicating the formation of an oxiranyl radical intermediate that is free to rotate during the reaction. Unexpectedly, the enzyme also catalyzes a side reaction in which oxiranyl-aldehydes undergo tandem deformylation to furnish alkanes two carbons shorter. We present evidence that this involves the rearrangement of the intermediate oxiranyl radical formed in the first step, resulting an aldehyde that is further deformylated in a second step. These observations provide support for a radical mechanism for deformylation and, furthermore, allow the lifetime of the radical intermediate to be estimated based on prior measurements of rate constants for the rearrangement of oxiranyl radicals. PMID:24313866

  16. Identification of Distinct Internal and External Isozymes of Carbonic Anhydrase in Chlorella saccharophila.

    PubMed

    Williams, T. G.; Colman, B.

    1993-11-01

    External carbonic anhydrase (CA) was detected in whole cells of alkaline-grown Chlorella saccharophila but was suppressed by growth at acid pH or growth on elevated levels of CO2. Internal CA activity was measured potentiometrically as an increase in activity in cell extracts over that of intact cells. Cells grown under all conditions had equal levels of internal CA activity. Two isozymes were identified after electrophoretic separation of soluble proteins on cellulose acetate plates. The fast isozyme was found in cells grown under all conditions, whereas the slow isozyme was found only in cells grown at alkaline pH. Western blot analysis following sodium dodecyl sulfate-polyacrylamide gel electrophoresis using antibodies produced against the periplasmic form of CA from Chlamydomonas reinhardtii revealed a single band at 39 kD, which did not change in intensity between growth conditions and was associated only with proteins eluted from the fast band. The slow isozyme was inactivated by incubation of cell extract at 30[deg]C and by incubation in 10 mM dithiothreitol, whereas the internal form was unaffected. These results indicate that external and internal forms of CA differ in structure and their activities respond differently to environmental conditions. PMID:12231991

  17. Identification of IAA-oxidase in peroxidase isozymes from cotton plant leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the functions of plant peroxidase is to regulate the indole acetic acid (IAA) hormonal level by oxidizing it to inactive 3-methyleneoxyindole. IAA-binding proteins and plant peroxidase revealed five structurally similar fragments. We have isolated peroxidase isozymes with IAA-oxidase activit...

  18. Genetics Home Reference: pyruvate dehydrogenase deficiency

    MedlinePlus

    ... control the activity of the complex: pyruvate dehydrogenase phosphatase turns on (activates) the complex, while pyruvate dehydrogenase ... binding protein (the PDHX gene), and pyruvate dehydrogenase phosphatase (the PDP1 gene) have been identified in people ...

  19. Physiological implications of the specificity of acetohydroxy acid synthase isozymes of enteric bacteria.

    PubMed Central

    Barak, Z; Chipman, D M; Gollop, N

    1987-01-01

    The rates of formation of the two alternative products of acetohydroxy acid synthase (AHAS) have been determined by a new analytical method (N. Gollop, Z. Barak, and D. M. Chipman, Anal. Biochem., 160:323-331, 1987). For each of the three distinct isozymes of AHAS in Escherichia coli and Salmonella typhimurium, a specificity ratio, R, was defined: Formula: see text, which is constant over a wide range of substrate concentrations. This is consistent with competition between pyruvate and 2-ketobutyrate for an active acetaldehyde intermediate formed irreversibly after addition of the first pyruvate moiety to the enzyme. Isozyme I showed no product preference (R = 1), whereas isozymes II and III form acetohydroxybutyrate (AHB) at approximately 180- and 60-fold faster rates, respectively, than acetolactate (AL) at equal pyruvate and 2-ketobutyrate concentrations. R values higher than 60 represent remarkably high specificity in favor of the substrate with one extra methylene group. In exponentially growing E. coli cells (under aerobic growth on glucose), which contain about 300 microM pyruvate and only 3 microM 2-ketobutyrate, AHAS I would produce almost entirely AL and only 1 to 2% AHB. However, isozymes II and III would synthesize AHB (on the pathway to Ile) and AL (on the pathway to valine-leucine) in essentially the ratio required for protein synthesis. The specificity ratio R of any AHAS isozyme was affected neither by the natural feedback inhibitors (Val, Ile) nor by the pH. On the basis of the specificities of the isozymes, the known regulation of AHAS I expression by the catabolite repression system, and the reported behavior of bacterial mutants containing single AHAS isozymes, we suggest that AHAS I enables a bacterium to cope with poor carbon sources, which lead to low endogenous pyruvate concentrations. Although AHAS II and III are well suited to producing the branched-chain amino acid precursors during growth on glucose, they would fail to provide

  20. Physiological implications of the specificity of acetohydroxy acid synthase isozymes of enteric bacteria.

    PubMed

    Barak, Z; Chipman, D M; Gollop, N

    1987-08-01

    The rates of formation of the two alternative products of acetohydroxy acid synthase (AHAS) have been determined by a new analytical method (N. Gollop, Z. Barak, and D. M. Chipman, Anal. Biochem., 160:323-331, 1987). For each of the three distinct isozymes of AHAS in Escherichia coli and Salmonella typhimurium, a specificity ratio, R, was defined: Formula: see text, which is constant over a wide range of substrate concentrations. This is consistent with competition between pyruvate and 2-ketobutyrate for an active acetaldehyde intermediate formed irreversibly after addition of the first pyruvate moiety to the enzyme. Isozyme I showed no product preference (R = 1), whereas isozymes II and III form acetohydroxybutyrate (AHB) at approximately 180- and 60-fold faster rates, respectively, than acetolactate (AL) at equal pyruvate and 2-ketobutyrate concentrations. R values higher than 60 represent remarkably high specificity in favor of the substrate with one extra methylene group. In exponentially growing E. coli cells (under aerobic growth on glucose), which contain about 300 microM pyruvate and only 3 microM 2-ketobutyrate, AHAS I would produce almost entirely AL and only 1 to 2% AHB. However, isozymes II and III would synthesize AHB (on the pathway to Ile) and AL (on the pathway to valine-leucine) in essentially the ratio required for protein synthesis. The specificity ratio R of any AHAS isozyme was affected neither by the natural feedback inhibitors (Val, Ile) nor by the pH. On the basis of the specificities of the isozymes, the known regulation of AHAS I expression by the catabolite repression system, and the reported behavior of bacterial mutants containing single AHAS isozymes, we suggest that AHAS I enables a bacterium to cope with poor carbon sources, which lead to low endogenous pyruvate concentrations. Although AHAS II and III are well suited to producing the branched-chain amino acid precursors during growth on glucose, they would fail to provide

  1. One-Pot Amide Bond Formation from Aldehydes and Amines via a Photoorganocatalytic Activation of Aldehydes.

    PubMed

    Papadopoulos, Giorgos N; Kokotos, Christoforos G

    2016-08-19

    A mild, one-pot, and environmentally friendly synthesis of amides from aldehydes and amines is described. Initially, a photoorganocatalytic reaction of aldehydes with di-isopropyl azodicarboxylate leads to an intermediate carbonyl imide, which can react with a variety of amines to afford the desired amides. The initial visible light-mediated activation of a variety of monosubstituted or disubstituted aldehydes is usually fast, occurring in a few hours. Following the photocatalytic reaction, addition of the primary amine at room temperature or the secondary amine at elevated temperatures leads to the corresponding amide from moderate to excellent yields without epimerization. This methodology was applied in the synthesis of Moclobemide, a drug against depression and social anxiety. PMID:27227271

  2. Erwinia chrysanthemi EC16 Produces a Second Set of Plant-Inducible Pectate Lyase Isozymes

    PubMed Central

    Kelemu, Segenet; Collmer, Alan

    1993-01-01

    The enterobacterium Erwinia chrysanthemi causes soft-rot diseases involving extensive tissue maceration in a wide variety of plants and secretes multiple pectic enzymes that degrade plant cell walls and middle lamellae. An E. chrysanthemi mutant with directed deletions or insertions in genes pehX, pelX, pelA, pelB, pelC, and pelE, which encode exo-poly-α-d-galacturonosidase, exopolygalacturonate lyase, and four isozymes of pectate lyase, respectively, was constructed by the marker exchange of a cloned pehX::TnphoA fragment into E. chrysanthemi CUCPB5010, a Δ(pelA pelE) Δ(pelB pelC)::28bp Δ(pelX)Δ4bp derivative of strain EC16. This mutant, E. chrysanthemi CUCPB5012, no longer caused pitting in a standard pectate semisolid agar medium used to detect pectolytic activity in bacteria. Nevertheless, the mutant still macerated leaves of chrysanthemum (Chrysanthemum morifolium), although with reduced virulence. The mutant was found to produce significant pectate lyase activity in rotting chrysanthemum tissue and in minimal media containing chrysanthemum extracts or cell walls as the sole carbon source. Activity-stained, ultra-thin-layer isoelectric focusing gels revealed the presence in these preparations of several pectate lyase isozymes with pIs ranging from highly acidic to highly alkaline. Sterile culture fluids containing these isozymes were able to macerate chrysanthemum leaf tissue. Unlike the products of the pelA, pelB, pelC, and pelE genes in E. chrysanthemi EC16, these plant-inducible pectate lyase isozymes were not produced in minimal medium containing pectate. The results suggest that E. chrysanthemi produces two sets of independently regulated pectate lyase isozymes that are capable of macerating plant tissues. Images PMID:16348952

  3. Control of aldehyde synthesis in the luminous bacterium Beneckea harveyi.

    PubMed Central

    Ulitzur, S; Hastings, J W

    1979-01-01

    Some of the Beneckea harveyi dim aldehyde mutants, all of which emit light upon addition of exogenous long-chain aldehyde, also emit light when myristic acid is added. Analysis of these myristic acid-responsive mutants indicates that they are blocked before fatty acid formation, whereas another class of mutants, which respond only to aldehyde, appear to be defective in the enzyme(s) involved in the conversion of acid to aldehyde. Evidence is presented that this activity, designated myristic acid reductase, is coinduced with luciferase and is involved in the recycling of acid produced in the luciferase reaction, with specificity for the C14 compounds. PMID:311359

  4. NAD(+)-independent aldehyde oxidase catalyzes cofactor balanced 3-hydroxypropionic acid production in Klebsiella pneumoniae.

    PubMed

    Li, Ying; Liu, Luo; Tian, Pingfang

    2014-11-01

    The limiting step for biosynthesis of 3-hydroxypropionic acid (3-HP) in Klebsiella pneumoniae is the conversion of 3-hydroxypropionaldehyde (3-HPA) to 3-HP. This reaction is catalyzed by aldehyde dehydrogenase (ALDH) with NAD(+) as a cofactor. Although NAD(+)-dependent ALDH overexpression facilitates 3-HP biosynthesis, ALDH activity decreases and 3-HP stops accumulation when NAD(+) is exhausted. Here, we show that an NAD(+)-independent aldehyde oxidase (AOX) from Pseudomonas sp. AIU 362 holds promise for cofactor-balanced 3-HP production in K. pneumoniae. The AOX coding gene, alod, was heterologously expressed in E. coli and K. pneumoniae, and their respective crude cell extracts showed 38.1 U/mg and 16.6 U/mg activities toward propionaldehyde. The recombinant K. pneumoniae expressing alod showed 13.7 U/mg activity toward 3-HPA; K m and V max were 6.7 mM and 42 μM/min/mg, respectively. In shake-flask cultures, the recombinant K. pneumoniae strain produced 0.89 g 3-HP/l, twice that of the control. Moreover, it produced 3 g 3-HP/l during 24 h fed-batch cultivation in a 5 l bioreactor. The results indicate that AOX can efficiently convert 3-HPA into 3-HP. PMID:24980850

  5. Molecular Mechanisms of Aldehyde Toxicity: A Chemical Perspective

    PubMed Central

    2015-01-01

    Aldehydes are electrophilic compounds to which humans are pervasively exposed. Despite a significant health risk due to exposure, the mechanisms of aldehyde toxicity are poorly understood. This ambiguity is likely due to the structural diversity of aldehyde derivatives and corresponding differences in chemical reactions and biological targets. To gain mechanistic insight, we have used parameters based on the hard and soft, acids and bases (HSAB) theory to profile the different aldehyde subclasses with respect to electronic character (softness, hardness), electrophilic reactivity (electrophilic index), and biological nucleophilic targets. Our analyses indicate that short chain aldehydes and longer chain saturated alkanals are hard electrophiles that cause toxicity by forming adducts with hard biological nucleophiles, e.g., primary nitrogen groups on lysine residues. In contrast, α,β-unsaturated carbonyl derivatives, alkenals, and the α-oxoaldehydes are soft electrophiles that preferentially react with soft nucleophilic thiolate groups on cysteine residues. The aldehydes can therefore be grouped into subclasses according to common electronic characteristics (softness/hardness) and molecular mechanisms of toxicity. As we will discuss, the toxic potencies of these subgroups are generally related to corresponding electrophilicities. For some aldehydes, however, predictions of toxicity based on electrophilicity are less accurate due to inherent physicochemical variables that limit target accessibility, e.g., steric hindrance and solubility. The unsaturated aldehydes are also members of the conjugated type-2 alkene chemical class that includes α,β-unsaturated amide, ketone, and ester derivatives. Type-2 alkenes are electrophiles of varying softness and electrophilicity that share a common mechanism of toxicity. Therefore, exposure to an environmental mixture of unsaturated carbonyl derivatives could cause “type-2 alkene toxicity” through additive interactions

  6. Dehydrogenase genes in the ectomycorrhizal fungus Tricholoma vaccinum: A role for Ald1 in mycorrhizal symbiosis.

    PubMed

    Henke, Catarina; Jung, Elke-Martina; Voit, Annekatrin; Kothe, Erika; Krause, Katrin

    2016-02-01

    Ectomycorrhizal symbiosis is important for forest ecosystem functioning with tree-fungal cooperation increasing performance and countering stress conditions. Aldehyde dehydrogenases (ALDHs) are key enzymes for detoxification and thus may play a role in stress response of the symbiotic association. With this focus, eight dehydrogenases, Ald1 through Ald7 and TyrA, of the ectomycorrhizal basidiomycete Tricholoma vaccinum were characterized and phylogenetically investigated. Functional analysis was performed through differential expression analysis by feeding different, environmentally important substances. A strong effect of indole-3-acetic acid (IAA) was identified, linking mycorrhiza formation and auxin signaling between the symbiosis partners. We investigated ald1 overexpressing strains for performance in mycorrhiza with the host tree spruce (Picea abies) and observed an increased width of the apoplast, accommodating the Hartig' net hyphae of the T. vaccinum over-expressing transformants. The results support a role for Ald1 in ectomycorrhiza formation and underline functional differentiation within fungal aldehyde dehydrogenases in the family 1 of ALDHs. PMID:26344933

  7. Isolation and characterization of an inducible NAD-dependent butyraldehyde dehydrogenase from clostridium acetobutylicum

    SciTech Connect

    Schreiber, W.; Duerre, P.

    1996-12-31

    A NAD-dependent butyraldehyde dehydrogenase (BAD) has been purified from C. acetobutylicum DSM 792 and DSM 173 1. This key enzyme of butanol production, catalyzing the conversion of butyryl-CoA to butyraldehyde, was induced shortly before the onset of butanol production and proved to be oxygen-sensitive. A one step purification procedure on reactive green 19 allowed to purify the enzyme to homogeneity. The purified protein was found to be extremely unstable and could only partially be stabilized by addition of mercaptoethanol and storage below -20{degrees}C. The enzyme subunit had a molecular mass of 39.5 kDa. In the reverse reaction (butyryl-CoA-forming) the apparent pH optimum was 9.75 and Vmax was significantly higher with butyraldehyde and propionaldehyde than with acetaldehyde. BAD could also use NADP+, but NAD+ was the preferred coenzyme for the reverse reaction. The N-terminal amino acid sequence of the C. acetobutylicurn DSM 792 protein showed high homology to glyceraldehyde-3-phosphate dehydrogenases (GAP), especially to the protein of C. pasteurianum. Genomic libraries of C. acetobutylicum DSM 792 were screened by hybridization using PCR-generated heterologous probes encoding the gap gene of C. pasteurianum. Sequence analysis of the positive clones revealed high homology, but no identity to the N-terminal amino acid sequence of the butyraldehyde dehydrogenase. Thus, BAD from C. acetobutylicum is distinctly different from other reported aldehyde dehydrogenases with butyraldehyde dehydrogenase activity.

  8. Lactate dehydrogenase-elevating virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the taxonomic classification of Lactate dehydrogenase-elevating virus (LDV). Included are: host, genome, classification, morphology, physicochemical and physical properties, nucleic acid, proteins, lipids, carbohydrates, geographic range, phylogenetic properties, biologic...

  9. [Genetic differentiation of Caucasian wood mice: comparison of isozymic, chromosomal and molecular divergence].

    PubMed

    Chelomina, G N; Pavlenko, M V; Kartavtseva, I V; Boeskorov, G G; Liapunova, E A; Vorontsov, N N

    1998-02-01

    Data on the complex genetic analysis of three sympatric species of Caucasian wood mice, Apodemus ponticus, A. fulvipectus, and A. uralensis are presented. A high degree of genetic differentiation at the isozymic, karyological and molecular (nuclear DNA) levels was revealed. The genetic distances between each pair of species varied significantly within a wide range depending on the analyzed level of the organization of genetic material. Mean values of genetic divergence from one species to another were also variable. These findings indicated that evolution of chromosomes was slower than that of isozymes, and the degree of species divergence was similar on cytogenetic and molecular levels. They also suggested that the rates of species evolution could vary in different phyletic lineages and on different levels of organization. Some phyletic lineages of Apodemus could be distinguished by different directions of evolution. PMID:9589852

  10. Inhibition of rat steroid 5 alpha-reductase (isozyme 1) by suramin.

    PubMed

    Taylor, M F; Bhattacharyya, A K; Collins, D C

    1995-07-01

    In this study, we show the inhibition of rat steroid 5 alpha-reductase (isozyme 1) by suramin. The enzyme activity decreased in a dose-dependent manner as suramin concentrations increased with the calculated drug dose required for 50% inhibition (at 5 microM testosterone and 200 microM NADPH) being 13 microM. Suramin showed non-competitive inhibition of 5 alpha-reductase with respect to testosterone (KT1 = 2.4 microM) and competitive inhibition with respect to NADPH (KiNADPH = 220 nM). Furthermore, suramin and NADP+, but not NAD+, protected 5 alpha-reductase from labeling by 2-azido-NADP+, a photoactive probe which has recently been used to identify the NADPH binding domain of 5 alpha-reductase. These results suggest that suramin inhibits rat steroid 5 alpha-reductase (isozyme 1) at the level of NADPH binding to the enzyme. PMID:7482629

  11. The white-rot fungus Pleurotus ostreatus secretes laccase isozymes with different substrate specificities.

    PubMed

    Mansur, Mariana; Arias, María E; Copa-Patiño, José L; Flärdh, María; González, Aldo E

    2003-01-01

    Four laccase isozymes (LCC1, LCC2, LCC3 and LCC4) synthesized by Pleurotus ostreatus strain V-184 were purified and characterized. LCC1 and LCC2 have molecular masses of about 60 and 65 kDa and exhibited the same pI value (3.0). Their N termini were sequenced, revealing the same amino acid sequence and homology with laccases from other microorganisms. Laccases LCC3 and LCC4 were characterized by SDS-PAGE, estimating their molecular masses around 80 and 82 kDa, respectively. By native isoelectrofocusing, their pI values were 4.7 and 4.5, respectively. When staining with ABTS and guaiacol in native polyacrilamide gels, different specificities were observed for LCC1/LCC2 and LCC3/LCC4 isozymes. PMID:21149010

  12. Morphology and isozyme band-profile as sexual determinant of nutmeg plant (Myristica fragrants Houttj).

    NASA Astrophysics Data System (ADS)

    Karmanah; Maslahat, M.; Nurhayati, dan L.

    2016-01-01

    Sex information in nutmeg plant is important to distinguish between male and female species. The recommendation of optimum sex-ratio for a nutmeg plantation is 1:10. This research is aimed to discover the morphological characteristic of nutmeg plant and the difference of leaf pattern as sexual determinant between male and female plant with the comparison of isozyme analysis. The result of morphological identification provided from 3 research farm location indicated that female nutmeg was higher, with longer and wider leaf, more vein, bigger diameter of stem and branching angle as compared to male nutmeg. Two parameters which were widht of leaf and branching angle showed significant differences, where female nutmeg plants have wider leaves and branching angle. Isozyme analysis suggested that the analysis of peroxidase enzyme (PER) was better and able to provide more information than aspartarte amino transferase (AAT) and acid phospatase (ACP) Enzymes.

  13. Application of repeated aspartate tags to improving extracellular production of Escherichia coli L-asparaginase isozyme II.

    PubMed

    Kim, Sun-Ki; Min, Won-Ki; Park, Yong-Cheol; Seo, Jin-Ho

    2015-11-01

    Asparaginase isozyme II from Escherichia coli is a popular enzyme that has been used as a therapeutic agent against acute lymphoblastic leukemia. Here, fusion tag systems consisting of the pelB signal sequence and various lengths of repeated aspartate tags were devised to highly express and to release active asparaginase isozyme II extracellularly in E. coli. Among several constructs, recombinant asparaginase isozyme II fused with the pelB signal sequence and five aspartate tag was secreted efficiently into culture medium at 34.6 U/mg cell of specific activity. By batch fermentation, recombinant E. coli produced 40.8 U/ml asparaginase isozyme II in the medium. In addition, deletion of the gspDE gene reduced extracellular production of asparaginase isozyme II, indicating that secretion of recombinant asparaginase isozyme II was partially ascribed to the recognition by the general secretion machinery. This tag system composed of the pelB signal peptide, and repeated aspartates can be applied to extracellular production of other recombinant proteins. PMID:26320714

  14. Modulation of superoxide dismutase (SOD) isozymes by organ development and high long-term salinity in the halophyte Cakile maritima.

    PubMed

    Houmani, Hayet; Rodríguez-Ruiz, Marta; Palma, José M; Abdelly, Chedly; Corpas, Francisco J

    2016-05-01

    Superoxide dismutase (SOD) activity catalyzes the disproportionation of superoxide radicals into hydrogen peroxide and oxygen. This enzyme is considered to be a first line of defense for controlling the production of reactive oxygen species (ROS). In this study, the number and type of SOD isozymes were identified in the principal organs (roots, stems, leaves, flowers, and seeds) of Cakile maritima. We also analyzed the way in which the activity of these SOD isozymes is modulated during development and under high long-term salinity (400 mM NaCl) stress conditions. The data indicate that this plant contains a total of ten SOD isozymes: two Mn-SODs, one Fe-SOD, and seven CuZn-SODs, with the Fe-SOD being the most prominent isozyme in the different organs analyzed. Moreover, the modulation of SOD isozymes, particularly CuZn-SODs, was only detected during development and under severe salinity stress conditions. These data suggest that, in C. maritima, the occurrence of these CuZn-SODs in roots and leaves plays an adaptive role since this CuZn-SOD isozyme might replace the diminished Fe-SOD activity under salinity stress to overcome this adverse environmental condition. PMID:26159565

  15. Alcohol Dehydrogenase from Methylobacterium organophilum

    PubMed Central

    Wolf, H. J.; Hanson, R. S.

    1978-01-01

    The alcohol dehydrogenase from Methylobacterium organophilum, a facultative methane-oxidizing bacterium, has been purified to homogeneity as indicated by sodium dodecyl sulfate-gel electrophoresis. It has several properties in common with the alcohol dehydrogenases from other methylotrophic bacteria. The active enzyme is a dimeric protein, both subunits having molecular weights of about 62,000. The enzyme exhibits broad substrate specificity for primary alcohols and catalyzes the two-step oxidation of methanol to formate. The apparent Michaelis constants of the enzyme are 2.9 × 10−5 M for methanol and 8.2 × 10−5 M for formaldehyde. Activity of the purified enzyme is dependent on phenazine methosulfate. Certain characteristics of this enzyme distinguish it from the other alcohol dehydrogenases of other methylotrophic bacteria. Ammonia is not required for, but stimulates the activity of newly purified enzyme. An absolute dependence on ammonia develops after storage of the purified enzyme. Activity is not inhibited by phosphate. The fluorescence spectrum of the enzyme indicates that it and the cofactor associated with it may be chemically different from the alcohol dehydrogenases from other methylotrophic bacteria. The alcohol dehydrogenases of Hyphomicrobium WC-65, Pseudomonas methanica, Methylosinus trichosporium, and several facultative methylotrophs are serologically related to the enzyme purified in this study. The enzymes of Rhodopseudomonas acidophila and of organisms of the Methylococcus group did not cross-react with the antiserum prepared against the alcohol dehydrogenase of M. organophilum. Images PMID:80974

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

    DOE PAGESBeta

    Clarkson, Sonya M.; Hamilton-Brehm, Scott D.; Giannone, Richard J.; Engle, Nancy L.; Tschaplinski, Timothy J.; Hettich, Robert L.; Elkins, James G.

    2014-12-03

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

  17. Distinct 1-monoacylglycerol and 2-monoacylglycerol kinase activities of diacylglycerol kinase isozymes.

    PubMed

    Sato, Yuriko; Murakami, Chiaki; Yamaki, Atsumi; Mizuno, Satoru; Sakai, Hiromichi; Sakane, Fumio

    2016-09-01

    Diacylglycerol kinase (DGK) consists of ten isozymes and is involved in a wide variety of patho-physiological events. However, the enzymological properties of DGKs have not been fully understood. In this study, we performed a comprehensive analysis on the 1-monoacylglycerol kinase (MGK) and 2-MGK activities of ten DGK isozymes. We revealed that type I (α, β and γ), type II (δ, η and κ) and type III (ε) DGKs have 7.9-19.2% 2-MGK activity compared to their DGK activities, whereas their 1-MGK activities were <3.0%. Both the 1-MGK and 2-MGK activities of the type IV DGKs (ζ and ι) were <1% relative to their DGK activities. Intriguingly, type V DGKθ has approximately 6% 1-MGK activity and <2% 2-MGK activity compared to its DGK activity. Purified DGKθ exhibited the same results, indicating that its 1-MGK activity is intrinsic. Therefore, DGK isozymes are categorized into three types with respect to their 1-MGK and 2-MGK activities: those having (1) 2-MGK activity relatively stronger than their 1-MGK activity (types I-III), (2) only negligible 1-MGK and 2-MGK activities (type IV), and (3) 1-MGK activity stronger than its 2-MGK activity (type V). The 1-MGK activity of DGKθ and the 2-MGK activity of DGKα were stronger than those of the acylglycerol kinase reported as 1-MGK and 2-MGK to date. The presence or absence of 1-MGK and 2-MGK activities may be essential to the patho-physiological functions of each DGK isozyme. PMID:27346717

  18. Importance of the Voltage Dependence of Cardiac Na/K ATPase Isozymes.

    PubMed

    Stanley, Christopher M; Gagnon, Dominique G; Bernal, Adam; Meyer, Dylan J; Rosenthal, Joshua J; Artigas, Pablo

    2015-11-01

    Cardiac cells express more than one isoform of the Na, K-ATPase (NKA), the heteromeric enzyme that creates the Na(+) and K(+) gradients across the plasmalemma. Cardiac isozymes contain one catalytic α-subunit isoform (α1, α2, or α3) associated with an auxiliary β-subunit isoform (β1 or β2). Past studies using biochemical approaches have revealed minor kinetic differences between isozymes formed by different α-β isoform combinations; these results make it difficult to understand the physiological requirement for multiple isoforms. In intact cells, however, NKA enzymes operate in a more complex environment, which includes a substantial transmembrane potential. We evaluated the voltage dependence of human cardiac NKA isozymes expressed in Xenopus oocytes, and of native NKA isozymes in rat ventricular myocytes, using normal mammalian physiological concentrations of Na(+)o and K(+)o. We demonstrate that although α1 and α3 pumps are functional at all physiologically relevant voltages, α2β1 pumps and α2β2 pumps are inhibited by ∼75% and ∼95%, respectively, at resting membrane potentials, and only activate appreciably upon depolarization. Furthermore, phospholemman (FXYD1) inhibits pump function without significantly altering the pump's voltage dependence. Our observations provide a simple explanation for the physiological relevance of the α2 subunit (∼20% of total α subunits in rat ventricle): they act as a reserve and are recruited into action for extra pumping during the long-lasting cardiac action potential, where most of the Na(+) entry occurs. This strong voltage dependence of α2 pumps also helps explain how cardiotonic steroids, which block NKA pumps, can be a beneficial treatment for heart failure: by only inhibiting the α2 pumps, they selectively reduce NKA activity during the cardiac action potential, leading to an increase in systolic Ca(2+), due to reduced extrusion through the Na/Ca exchanger, without affecting resting Na(+) and Ca(2

  19. The effects of cyclooxygenase isozyme inhibition on incisional wound healing in mouse skin.

    PubMed

    Müller-Decker, Karin; Hirschner, Wolfgang; Marks, Friedrich; Fürstenberger, Gerhard

    2002-11-01

    In addition to their proinflammatory activities, prostaglandins recently have been shown to be beneficial in the resolution of tissue injury and inflammation. Thus, inhibition of cyclooxygenase-2, the predominant prostaglandin endoperoxide synthase under these conditions, may not only result in attenuating the inflammatory response but also in delaying tissue regeneration and repair. To this end, we investigated cyclooxygenase isozyme expression and the effects of cyclooxygenase inhibitors on wound healing upon full-thickness incisions in mouse skin. Immunohistochemical analysis revealed prominent expression of cyclooxygenase isozymes in keratinocytes of the hyperplastic epithelium, with cyclooxygenase-1 immunosignals predominating in the suprabasal compartment and cyclooxygenase-2 immunosignals spread throughout the whole epidermis. Moreover, dendritic cells, resembling Langerhans cells, as well as endothelial cells and macrophages in the vicinity of or within the granulation tissue were found to express both isozymes. Inhibition of prostaglandin E2 synthesis by oral administration of the cyclooxygenase-1-selective inhibitor SC-560 or the cyclooxygenase-2-selective inhibitor valdecoxib did not retard wound healing in mouse skin macroscopically. Except for a slight transient retardation of epithelialization early after wounding wound-induced neoangiogenesis, collagen deposition, and the restoration of tensile strength were not delayed by these agents. Likewise, the nonselective inhibitor indomethacin had no effect on the tensile strength of incisional skin wounds. PMID:12445211

  20. Conversion of crude Jatropha curcas seed oil into biodiesel using liquid recombinant Candida rugosa lipase isozymes.

    PubMed

    Kuo, Ting-Chun; Shaw, Jei-Fu; Lee, Guan-Chiun

    2015-09-01

    The versatile Candida rugosa lipase (CRL) has been widely used in biotechnological applications. However, there have not been feasibility reports on the transesterification of non-edible oils to produce biodiesel using the commercial CRL preparations, mixtures of isozymes. In the present study, four liquid recombinant CRL isozymes (CRL1-CRL4) were investigated to convert various non-edible oils into biodiesel. The results showed that recombinant CRL2 and CRL4 exhibited superior catalytic efficiencies for producing fatty acid methyl ester (FAME) from Jatropha curcas seed oil. A maximum 95.3% FAME yield was achieved using CRL2 under the optimal conditions (50 wt% water, an initial 1 equivalent of methanol feeding, and an additional 0.5 equivalents of methanol feeding at 24h for a total reaction time of 48 h at 37 °C). We concluded that specific recombinant CRL isozymes could be excellent biocatalysts for the biodiesel production from low-cost crude Jatropha oil. PMID:26011691

  1. Effects of pristane on cytochrome P450 isozyme expression in rat tissues.

    PubMed

    Howard, Carolyn B; Samuel, Jacqueline; Henderson, Shalonda B; Stevens, Jacqueline; Thomas, Paul E; Cuchens, Marvin A

    2005-04-01

    Chemical carcinogenesis studies are powerful tools to obtain information on potential mechanisms of chemical factors for malignancies. In this study Western blot analyses, using monoclonal antibodies specific for three different cytochrome P450 (CYP) isozymes (CYP1A1, CYP1A2 and CYP2B), were employed to examine the effect(s) of 3-methylcholanthrene and/or pristane (2,6,10,14-tetramethylpentadecane) on the basal and inducible levels of expression of CYP proteins within Copenhagen rat tissues. Pristane exposure led to tissue specific differences in the CYP isozymes expressed and elicited increased CYP protein expression over 3-methylcholanthrene induced levels in microsomes isolated from liver, Peyer's Patches, and thymus. Within the context of the chemical carcinogenesis model employed in this study, these observations correlated with the induction of B-cell malignancies by low doses of 3-methylcholanthrene and of thymic lymphomas by a high 3-methylcholanthrene dose. The data suggest that pristane treatment affects CYP isozyme expression. This pristane-mediated effect clearly could be a contributing factor in the chemical carcinogenesis of the previously observed lymphoid malignancies, and a possible basis for the tumor enhancing effects of pristane. PMID:16708425

  2. Functional reclassification of the putative cinnamyl alcohol dehydrogenase multigene family in Arabidopsis

    PubMed Central

    Kim, Sung-Jin; Kim, Mi-Ran; Bedgar, Diana L.; Moinuddin, Syed G. A.; Cardenas, Claudia L.; Davin, Laurence B.; Kang, ChulHee; Lewis, Norman G.

    2004-01-01

    Of 17 genes annotated in the Arabidopsis genome database as cinnamyl alcohol dehydrogenase (CAD) homologues, an in silico analysis revealed that 8 genes were misannotated. Of the remaining nine, six were catalytically competent for NADPH-dependent reduction of p-coumaryl, caffeyl, coniferyl, 5-hydroxyconiferyl, and sinapyl aldehydes, whereas three displayed very low activity and only at very high substrate concentrations. Of the nine putative CADs, two (AtCAD5 and AtCAD4) had the highest activity and homology (≈83% similarity) relative to bona fide CADs from other species. AtCAD5 used all five substrates effectively, whereas AtCAD4 (of lower overall catalytic capacity) poorly used sinapyl aldehyde; the corresponding 270-fold decrease in kenz resulted from higher Km and lower kcat values, respectively. No CAD homologue displayed a specific requirement for sinapyl aldehyde, which was in direct contrast with unfounded claims for a so-called sinapyl alcohol dehydrogenase in angiosperms. AtCAD2, 3, as well as AtCAD7 and 8 (highest homology to sinapyl alcohol dehydrogenase) were catalytically less active overall by at least an order of magnitude, due to increased Km and lower kcat values. Accordingly, alternative and/or bifunctional metabolic roles of these proteins in plant defense cannot be ruled out. Comprehensive analyses of lignified tissues of various Arabidopsis knockout mutants (for AtCAD5, 6, and 9) at different stages of growth/development indicated the presence of functionally redundant CAD metabolic networks. Moreover, disruption of AtCAD5 expression had only a small effect on either overall lignin amounts deposited, or on syringyl-guaiacyl compositions, despite being the most catalytically active form in vitro. PMID:14745009

  3. Specific genetic markers for wheat, spelt, and four wild relatives: comparison of isozymes, RAPDs, and wheat microsatellites.

    PubMed

    Guadagnuolo, R; Bianchi, D S; Felber, F

    2001-08-01

    Three types of markers-isozymes, RAPDs (random amplified polymorphic DNAs), and wheat microsatellites- were tested on wheat, spelt, and four wild wheat relatives (Aegilops cylindrica, Elymus caninus, Hordeum marinum, and Agropyron junceum). The aim was to evaluate their capability to provide specific markers for differentiation of the cultivated and wild species. The markers were set up for subsequent detection of hybrids and introgression of wheat DNA into wild relatives. All markers allowed differentiation of the cultivated from the wild species. Wheat microsatellites were not amplified in all the wild relatives, whereas RAPDs and isozymes exhibited polymorphism for all species. The dendrograms obtained with RAPD and isozyme data separated Swiss wheat cultivars from those collected in Austria and England, while no difference was found between Swiss spelt and wheat. RAPD data provided a weak discrimination between English and Austrian E. caninus. The microsatellite-based dendrogram discriminated populations of Ae. cylindrica, but no clear separation of H. marinum from E. caninus was revealed. The similarity matrices based on the three different sets of data were strongly correlated. The highest value was recorded between the matrices based on RAPDs and isozymes (Mantel's test, r = 0.93). Correlations between the similarity matrix based on microsatellites and matrices based on RAPDs and isozymes were lower: 0.74 and 0.68, respectively. While microsatellites are very useful for comparisons of closely related accessions, they are less suitable for studies involving less-related taxa. Isozymes provide interesting markers for species differentiation, but their use seems less appropriate for studies of within-species genetic variation. RAPDs can produce a large set of markers, which can be used for the evaluation of both between- and within-species genetic variation, more rapidly and easily than isozymes and microsatellites. PMID:11550895

  4. Biogenic aldehyde determination by reactive paper spray ionization mass spectrometry.

    PubMed

    Bag, Soumabha; Hendricks, P I; Reynolds, J C; Cooks, R G

    2015-02-20

    Ionization of aliphatic and aromatic aldehydes is improved by performing simultaneous chemical derivatization using 4-aminophenol to produce charged iminium ions during paper spray ionization. Accelerated reactions occur in the microdroplets generated during the paper spray ionization event for the tested aldehydes (formaldehyde, n-pentanaldehyde, n-nonanaldehyde, n-decanaldehyde, n-dodecanaldehyde, benzaldehyde, m-anisaldehyde, and p-hydroxybenzaldehyde). Tandem mass spectrometric analysis of the iminium ions using collision-induced dissociation demonstrated that straight chain aldehydes give a characteristic fragment at m/z 122 (shown to correspond to protonated 4-(methyleneamino)phenol), while the aromatic aldehyde iminium ions fragment to give a characteristic product ion at m/z 120. These features allow straightforward identification of linear and aromatic aldehydes. Quantitative analysis of n-nonaldehyde using a benchtop mass spectrometer demonstrated a linear response over 3 orders of magnitude from 2.5 ng to 5 μg of aldehyde loaded on the filter paper emitter. The limit of detection was determined to be 2.2 ng for this aldehyde. The method had a precision of 22%, relative standard deviation. The experiment was also implemented using a portable ion trap mass spectrometer. PMID:25682245

  5. Michael hydratase alcohol dehydrogenase or just alcohol dehydrogenase?

    PubMed Central

    2014-01-01

    The Michael hydratase – alcohol dehydrogenase (MhyADH) from Alicycliphilus denitrificans was previously identified as a bi-functional enzyme performing a hydration of α,β-unsaturated ketones and subsequent oxidation of the formed alcohols. The investigations of the bi-functionality were based on a spectrophotometric assay and an activity staining in a native gel of the dehydrogenase. New insights in the recently discovered organocatalytic Michael addition of water led to the conclusion that the previously performed experiments to identify MhyADH as a bi-functional enzyme and their results need to be reconsidered and the reliability of the methodology used needs to be critically evaluated. PMID:24949265

  6. Tea triterpenoidal saponins from the roots of Camellia sinensis have inhibitory effects against alcohol dehydrogenase.

    PubMed

    Varughese, Titto; Manir, Md Maniruzzaman; Rahaman, Mozahidur; Kim, Jeong Kee; Lee, Byeong-Gon; Moon, Surk-Sik

    2011-12-01

    Ten new polyhydroxyolean-12-ene pentacyclic triterpenoidal saponins, named rogchaponins 1-10, were isolated from the methanolic extract of the roots of Camellia sinensis by a series of chromatographic methods (silica gel flash column and C18 MPLC followed by C18 HPLC). Their structures were established by 1D and 2D-NMR techniques along with IR and HR-TOF-MS. Rogchaponins R4 ( 4) and R5 (5) showed inhibitory activities against yeast alcohol dehydrogenase (ADH) with IC (50) values of 16.1 ± 3.2 and 15.4 ± 3.3 µM, respectively. A 4-methylpyrazole positive control exhibited an IC (50) of 2750 ± 50 µM. However, the saponins showed no inhibitory activity against yeast aldehyde dehydrogenase (ALDH). PMID:21786220

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

    PubMed Central

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

    2008-01-01

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

  8. NADH dehydrogenase: a new molecular marker for homoeology group 4 in Triticeae. A map of the 4RS chromosome arm in rye.

    PubMed

    Figueiras, A M; Zaragoza, C; Gallego, F J; Benito, C

    1991-12-01

    Structural gene loci encoding the monomeric isozymes nicotin adenin dinucleotide dehydrogenase (NADH dehydrogenase or NDH) have been located on the 4AL, 4Bα, and 4DS chromosome arms of Triticum aestivum cv "Chinese Spring", on the 4RS chromosome arm of Secale cereale cultivars "Imperial", "King II", "Dakold," and "Ailes," on the 4S(1) S/7S(1) chromosome of Aegilops longissima, the 4E of Elytrigia elongata, and the CSU-A of Aegilops umbellulata. All the results support the homoeologous relationships among these chromosomes in the five species studied. In addition, a map of the 4RS chromosome arm in cv "Ailes" has been realized, linking loci Pgm-1 (located on the 4RS chromosome arm) and Ndh-1 (17.91 cM), with an estimated distance between both loci and the centromere of 20.00 cM and 32.12 cM, respectively. PMID:24202354

  9. Genetics Home Reference: lactate dehydrogenase deficiency

    MedlinePlus

    ... dehydrogenase-B pieces (subunits) of the lactate dehydrogenase enzyme. This enzyme is found throughout the body and is important ... cells. There are five different forms of this enzyme, each made up of four protein subunits. Various ...

  10. Physiological Studies of Methane- and Methanol-Oxidizing Bacteria: Comparison of a Primary Alcohol Dehydrogenase from Methylococcus capsulatus (Texas Strain) and Pseudomonas Species M27

    PubMed Central

    Patel, R. N.; Bose, H. R.; Mandy, W. J.; Hoare, D. S.

    1972-01-01

    A primary alcohol dehydrogenase has been purified from Methylococcus capsulatus (Texas strain). The purified enzyme catalyzes the oxidation of methanol and formaldehyde to formate; other primary alcohols are oxidized to their corresponding aldehydes. Ammonium ions are required for enzyme activity. The enzyme has a molecular weight of 120,000 daltons and consists of two 62,000 molecular-weight subunits which dissociate at acidic pH. The enzyme is similar to an alcohol dehydrogenase enzyme isolated from Pseudomonas sp. M27. Images PMID:5022170

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

    SciTech Connect

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

    1985-12-01

    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.

  12. Direct Electrochemical Addressing of Immobilized Alcohol Dehydrogenase for the Heterogeneous Bioelectrocatalytic Reduction of Butyraldehyde to Butanol

    PubMed Central

    Schlager, S; Neugebauer, H; Haberbauer, M; Hinterberger, G; Sariciftci, N S

    2015-01-01

    Modified electrodes using immobilized alcohol dehydrogenase enzymes for the efficient electroreduction of butyraldehyde to butanol are presented as an important step for the utilization of CO2-reduction products. Alcohol dehydrogenase was immobilized, embedded in an alginate–silicate hybrid gel, on a carbon felt (CF) electrode. The application of this enzyme to the reduction of an aldehyde to an alcohol with the aid of the coenzyme nicotinamide adenine dinucleotide (NADH), in analogy to the final step in the natural reduction cascade of CO2 to alcohol, has been already reported. However, the use of such enzymatic reductions is limited because of the necessity of providing expensive NADH as a sacrificial electron and proton donor. Immobilization of such dehydrogenase enzymes on electrodes and direct pumping of electrons into the biocatalysts offers an easy and efficient way for the biochemical recycling of CO2 to valuable chemicals or alternative synthetic fuels. We report the direct electrochemical addressing of immobilized alcohol dehydrogenase for the reduction of butyraldehyde to butanol without consumption of NADH. The selective reduction of butyraldehyde to butanol occurs at room temperature, ambient pressure and neutral pH. Production of butanol was detected by using liquid-injection gas chromatography and was estimated to occur with Faradaic efficiencies of around 40 %. PMID:26113881

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

    DOEpatents

    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##

  14. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  15. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  16. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  17. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

  18. 27 CFR 24.183 - Use of distillates containing aldehydes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the fermentation of wine and then returned to the distilled spirits plant from which distillates were... fermentation of wine made from a different kind of fruit. Distillates containing aldehydes which are...

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

    NASA Technical Reports Server (NTRS)

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

    2000-01-01

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

  20. Differential substrate recognition by isozymes of plant protein-only Ribonuclease P.

    PubMed

    Howard, Michael J; Karasik, Agnes; Klemm, Bradley P; Mei, Christine; Shanmuganathan, Aranganathan; Fierke, Carol A; Koutmos, Markos

    2016-05-01

    Ribonuclease P (RNase P) catalyzes the cleavage of leader sequences from precursor tRNA (pre-tRNA). Typically, these enzymes are ribonucleic protein complexes that are found in all domains of life. However, a new class of RNase P has been discovered that is composed entirely of protein, termed protein-only RNase P (PRORP). To investigate the molecular determinants of PRORP substrate recognition, we measured the binding affinities and cleavage kinetics ofArabidopsisPRORP1 for varied pre-tRNA substrates. This analysis revealed that PRORP1 does not make significant contacts within the trailer or beyond N-1of the leader, indicating that this enzyme recognizes primarily the tRNA body. To determine the extent to which sequence variation within the tRNA body modulates substrate selectivity and to provide insight into the evolution and function of PRORP enzymes, we measured the reactivity of the threeArabidopsisPRORP isozymes (PRORP1-3) with four pre-tRNA substrates. A 13-fold range in catalytic efficiencies (10(4)-10(5)M(-1)s(-1)) was observed, demonstrating moderate selectivity for pre-tRNA substrates. Although PRORPs bind the different pre-tRNA species with affinities varying by as much as 100-fold, the three isozymes have similar affinities for a given pre-tRNA, suggesting similar binding modes. However, PRORP isozymes have varying degrees of cleavage fidelity, which is dependent on the pre-tRNA species and the presence of a 3'-discriminator base. This work defines molecular determinants of PRORP substrate recognition that provides insight into this new class of RNA processing enzymes. PMID:26966150

  1. Transcriptomic Assessment of Isozymes in the Biphenyl Pathway of Rhodococcus sp. Strain RHA1†

    PubMed Central

    Gonçalves, Edmilson R.; Hara, Hirofumi; Miyazawa, Daisuke; Davies, Julian E.; Eltis, Lindsay D.; Mohn, William W.

    2006-01-01

    Rhodococcus sp. RHA1 grows on a broad range of aromatic compounds and vigorously degrades polychlorinated biphenyls (PCBs). Previous work identified RHA1 genes encoding multiple isozymes for most of the seven steps of the biphenyl (BPH) pathway, provided evidence for coexpression of some of these isozymes, and indicated the involvement of some of these enzymes in the degradation of BPH, ethylbenzene (ETB), and PCBs. To investigate the expression of these isozymes and better understand how they contribute to the robust degradative capacity of RHA1, we comprehensively analyzed the 9.7-Mb genome of RHA1 for BPH pathway genes and characterized the transcriptome of RHA1 growing on benzoate (BEN), BPH, and ETB. Sequence analyses revealed 54 potential BPH pathway genes, including 28 not previously reported. Transcriptomic analysis with a DNA microarray containing 70-mer probes for 8,213 RHA1 genes revealed a suite of 320 genes of diverse functions that were upregulated during growth both on BPH and on ETB, relative to growth on the control substrate, pyruvate. By contrast, only 65 genes were upregulated during growth on BEN. Quantitative PCR assays confirmed microarray results for selected genes and indicated that some of the catabolic genes were upregulated over 10,000-fold. Our analysis suggests that up to 22 enzymes, including 8 newly identified ones, may function in the BPH pathway of RHA1. The relative expression levels of catabolic genes did not differ for BPH and ETB, suggesting a common regulatory mechanism. This study delineated a suite of catabolic enzymes for biphenyl and alkyl-benzenes in RHA1, which is larger than previously recognized and which may serve as a model for catabolism in other environmentally important bacteria having large genomes. PMID:16957245

  2. Reducing Isozyme Competition Increases Target Fatty Acid Accumulation in Seed Triacylglycerols of Transgenic Arabidopsis1[OPEN

    PubMed Central

    van Erp, Harrie; Shockey, Jay; Zhang, Meng; Adhikari, Neil D.; Browse, John

    2015-01-01

    One goal of green chemistry is the production of industrially useful fatty acids (FAs) in crop plants. We focus on hydroxy fatty acids (HFAs) and conjugated polyenoic FAs (α-eleostearic acids [ESAs]) using Arabidopsis (Arabidopsis thaliana) as a model. These FAs are found naturally in seed oils of castor (Ricinus communis) and tung tree (Vernicia fordii), respectively, and used for the production of lubricants, nylon, and paints. Transgenic oils typically contain less target FA than that produced in the source species. We hypothesized that competition between endogenous and transgenic isozymes for substrates limits accumulation of unique FAs in Arabidopsis seeds. This hypothesis was tested by introducing a mutation in Arabidopsis diacylglycerol acyltransferase1 (AtDGAT1) in a line expressing castor FA hydroxylase and acyl-Coenzyme A:RcDGAT2 in its seeds. This led to a 17% increase in the proportion of HFA in seed oil. Expression of castor phospholipid:diacylglycerol acyltransferase 1A in this line increased the proportion of HFA by an additional 12%. To determine if our observations are more widely applicable, we investigated if isozyme competition influenced production of ESA. Expression of tung tree FA conjugase/desaturase in Arabidopsis produced approximately 7.5% ESA in seed lipids. Coexpression of VfDGAT2 increased ESA levels to approximately 11%. Overexpression of VfDGAT2 combined with suppression of AtDGAT1 increased ESA accumulation to 14% to 15%. Our results indicate that isozyme competition is a limiting factor in the engineering of unusual FAs in heterologous plant systems and that reduction of competition through mutation and RNA suppression may be a useful component of seed metabolic engineering strategies. PMID:25739701

  3. Soybean roots retain the seed urease isozyme synthesized during embryo development. [Glycine max (L. ) Merr

    SciTech Connect

    Torisky, R.S.; Polacco, J.C. )

    1990-10-01

    Roots of young soybean (Glycine max (L.) Merr.) plants (up to 25 days old) contain two distinct urease isozymes, which are separable by hydroxyapatite chromatography. These two urease species (URE1 and URE2) differ in: (a) electrophoretic mobility in native gels, (b) pH dependence, and (c) recognition by a monoclonal antibody specific for the seed (embryo-specific) urease. By these parameters root URE1 urease is similar to the abundant embryo-specific urease isozyme, while root URE2 resembles the ubiquitous urease which has previously been found in all soybean tissues examined (leaf, embryo, seed coat, and cultured cells). The embryo-specific and ubiquitous urease isozymes are products of the Eu1 and Eu4 structural genes, respectively. Roots of the eu1-sun/eu1-sun genotype, which lacks the embryo-specific urease (i.e. seed urease-null), contain no URE1 urease activity. Roots of eu4/eu4, which lacks ubiquitous urease, lack the URE2 (leaflike) urease activity. From these genetic and biochemical criteria, then, we conclude that URE1 and URE2 are the embryo-specific and ubiquitous ureases, respectively. Adventitious roots generated from cuttings of any urease genotype lack URE1 activity. In seedling roots the seedlike (URE1) activity declines during development. Roots of 3-week-old plants contain 5% of the total URE1 activity of the radicle of 4-day-old seedlings, which, in turn, has approximately the same urease activity level as the dormant embryonic axis. The embryo-specific urease incorporates label from ({sup 35}S)methionine during embryo development but not during germination, indicating that there is no de novo synthesis of the embryo-specific (URE1) urease in the germinating root.

  4. Effects of divalent metal ions on the fluorescence and glucose-quenching of yeast hexokinase isozymes

    SciTech Connect

    Feldman, I.; Fame, T.

    1982-01-01

    Titrations of the quenching of the tryptophan fluorescence of yeast isozymes P-I and P-II by Mg/sup 2 +/, Mn/sup 2 +/, Ca/sup 2 +/, Cd/sup 2 +/, and Zn/sup 2 +/ ions and by glucose in the presence of each of these ions (10 mM) were performed at pH 5.5 and 6.5 at 20/sup 0/C. At the higher pH there was a reversal of the type of glucose-binding cooperativity for P-II from negative to positive when either Mn/sup 2 +/ or Ca/sup 2 +/ was present in the buffered isozyme solution before the glucose titration, whereas Mg/sup 2 +/ caused the glucose binding to become noncooperative. Zn/sup 2 +/ and Cd/sup 2 +/ decreased the glucose quenching of P-II fluorescence drastically at pH 5.5, from a value of 15% in buffer to only 4%. Glucose bindings to the P-I isozyme exhibited positive cooperativity in the presence of either Ca/sup 2 +/, Mg/sup 2 +/, or Mn/sup 2 +/, as well as the buffer alone, at both pH's. At the lower pH, Ca/sup 2 +/ enhanced the efficiency of glucose quenching of P-I fluorescence several-fold, while Mn/sup 2 +/ increased it only about 40% and Mg/sup 2 +/ not at all. The biological implications of these diverse metal ion effects are discussed.

  5. [Effect of Fuzheng Huayu recipe on CYP450 isozymes in normal and liver fibrosis rats].

    PubMed

    Zheng, Tian-hui; Liu, Wei; Li, Shu-ping; Yang, Tao; Wang, Chang-hong; Liu, Cheng-hai

    2015-03-01

    To study the effect of Fuzheng Huayu recipe (FZHY) on five types of isozymes of cytochrome P450 (CYP450) of normal and liver fibrosis rats by using the cocktail probe method. Dimethylnitrosamine ( DMN) was injected to induce the liver fibrosis model. After the tail vein injection with Cocktail probe solutions prepared with five CYP450s probe substrates (phenacetin-CYP1A2, omeprazole-CYP2C9, tolbutamide-CYP2C19, dextromethorphan-CYP2D6, midazolam-CYP3A4), the plasma concentrations of the five probe substrates were determined by LC-MS/MS, and the pharmacokinetic parameters were calculated by PK solutions 2. After the oral administration with FZHY, normal rats given phenacetin, omeprazole, tolbutamide and dextromethorphan showed increase in AUC(0-t) and decrease in CL to varying degrees, indicating that FZHY obviously inhibited the activities of CYP1A2, CYP2C9, CYP2C19 and CYP2D6 in normal rats, but with no obvious effect on the activity of CYP3A4. After the oral administration with FZHY, liver fibrosis rats treated with CYP2C9 showed the significant increase in AUC(0-t) and significant decrease in Vd, hut with no obvious changes in the pharmacokinetic parameters of other four types of prove substances, suggesting that FZHY could significantly inhibit the activity of CYP2C9 in rats but had no effect on the activities of CYP1A2, CYP2C19, CYP2D6 and CYP3A4. The changes in the activity of CYP450 isozymes in liver fibrosis rats may be the reason for FZHY's different effects on CYP450 isozymes in normal and liver fibrosis rats. PMID:26226765

  6. Photoorganocatalytic One-Pot Synthesis of Hydroxamic Acids from Aldehydes.

    PubMed

    Papadopoulos, Giorgos N; Kokotos, Christoforos G

    2016-05-10

    An efficient one-pot synthesis of hydroxamic acids from aldehydes and hydroxylamine is described. A fast, visible-light-mediated metal-free hydroacylation of dialkyl azodicarboxylates was used to develop the subsequent addition of hydroxylamine hydrochloride. A range of aliphatic and aromatic aldehydes were employed in this reaction to give hydroxamic acids in high to excellent yields. Application of the current methodology was demonstrated in the synthesis of the anticancer medicine vorinostat. PMID:27038037

  7. RS-Predictor models augmented with SMARTCyp reactivities: robust metabolic regioselectivity predictions for nine CYP isozymes.

    PubMed

    Zaretzki, Jed; Rydberg, Patrik; Bergeron, Charles; Bennett, Kristin P; Olsen, Lars; Breneman, Curt M

    2012-06-25

    RS-Predictor is a tool for creating pathway-independent, isozyme-specific, site of metabolism (SOM) prediction models using any set of known cytochrome P450 (CYP) substrates and metabolites. Until now, the RS-Predictor method was only trained and validated on CYP 3A4 data, but in the present study, we report on the versatility the RS-Predictor modeling paradigm by creating and testing regioselectivity models for substrates of the nine most important CYP isozymes. Through curation of source literature, we have assembled 680 substrates distributed among CYPs 1A2, 2A6, 2B6, 2C19, 2C8, 2C9, 2D6, 2E1, and 3A4, the largest publicly accessible collection of P450 ligands and metabolites released to date. A comprehensive investigation into the importance of different descriptor classes for identifying the regioselectivity mediated by each isozyme is made through the generation of multiple independent RS-Predictor models for each set of isozyme substrates. Two of these models include a density functional theory (DFT) reactivity descriptor derived from SMARTCyp. Optimal combinations of RS-Predictor and SMARTCyp are shown to have stronger performance than either method alone, while also exceeding the accuracy of the commercial regioselectivity prediction methods distributed by Optibrium and Schrödinger, correctly identifying a large proportion of the metabolites in each substrate set within the top two rank-positions: 1A2 (83.0%), 2A6 (85.7%), 2B6 (82.1%), 2C19 (86.2%), 2C8 (83.8%), 2C9 (84.5%), 2D6 (85.9%), 2E1 (82.8%), 3A4 (82.3%), and merged (86.0%). Comprehensive datamining of each substrate set and careful statistical analyses of the predictions made by the different models revealed new insights into molecular features that control metabolic regioselectivity and enable accurate prospective prediction of likely SOMs. PMID:22524152

  8. Beta-hexosaminidase isozymes and replacement therapy in Gm2 gangliosidosis.

    PubMed

    Rattazzi, M C

    1983-01-01

    The problem of cell targeting of lysosomal enzymes is a critical one in the development of strategies for therapeutic enzyme replacement in lysosomal storage diseases. In principle, posttranscriptional isozymes with different carbohydrate-chain composition may be helpful in exploiting existing glycosyl-specific receptors on target cells, if the receptor specificities are known and match the glycosyl composition of available isozymes. In practice, however, the choice is limited to isozymes that can be obtained from tissues available in abundance, such as placenta or blood plasma. Our early experiments show that one can interfere with the interaction between hepatic (RES) receptor and enzyme glycosyl chain, to obtain extrahepatic targeting of beta-hexosaminidase, with catabolic effects. This approach, of course, does not have an immediate therapeutic application, as it involves injection of large amounts of foreign material in order to inhibit hepatic uptake. Modification of the glycosyl chain may be the method of choice in selected instances [Furbish et al. 1981], but is applicability again depends on the knowledge of receptor specificity on target cells and on composition of the glycosyl chain of the enzyme in question. Our recent experiments are a first step toward obtaining enzyme forms that can be endocytosed efficiently by mechanisms that are independent of glycosyl-specific receptors. Charge-mediated, absorptive endocytosis can be obtained by covalent coupling of cationic PLL to beta-hexosaminidase. Given the abundance of negative surface charges on most cell types [Weiss, 1969], this approach may be applicable to different target cells and organs, and possibly also to lysosomal enzymes other than beta-hexosaminidase. The existence of glycosyl recognition signals on beta-hexosaminidase can be obviated by simple chemical manipulations, such as Na-metaperiodate oxidation, which effectively prevents hepatic RES uptake [Rattazzi et al, 1982]. In combination with

  9. Selectivity of pyripyropene derivatives in inhibition toward acyl-CoA:cholesterol acyltransferase 2 isozyme.

    PubMed

    Ohshiro, Taichi; Ohte, Satoshi; Matsuda, Daisuke; Ohtawa, Masaki; Nagamitsu, Tohru; Sunazuka, Toshiaki; Harigaya, Yoshihiro; Rudel, Lawrence L; Omura, Satoshi; Tomoda, Hiroshi

    2008-08-01

    Selectivity of 96 semisynthetic derivatives prepared from fungal pyripyropene A, originally isolated as a potent inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT), toward ACAT1 and ACAT2 isozymes was investigated in the cell-based assay using ACAT1- and ACAT2-expressing CHO cells. Eighteen derivatives including PR-71 (7-O-isocaproyl derivative) showed much more potent ACAT2 inhibition (IC50: 6.0 to 62 nM) than pyripyropene A (IC50: 70 nM). Among them, however, natural pyripyropene A showed the highest selectivity toward ACAT2 with a selectivity index (SI) of >1000, followed by PR-71 (SI, 667). PMID:18997389

  10. RS-Predictor models augmented with SMARTCyp reactivities: Robust metabolic regioselectivity predictions for nine CYP isozymes

    PubMed Central

    Zaretzki, Jed; Rydberg, Patrik; Bergeron, Charles; Bennett, Kristin P.; Olsen, Lars

    2012-01-01

    RS-Predictor is a tool for creating pathway-independent, isozyme-specific site of metabolism (SOM) prediction models using any set of known cytochrome P450 substrates and metabolites. Until now, the RS-Predictor method was only trained and validated on CYP 3A4 data, but in the present study we report on the versatility the RS-Predictor modeling paradigm by creating and testing regioselectivity models for substrates of the nine most important CYP isozymes. Through curation of source literature, we have assembled 680 substrates distributed among CYPs 1A2, 2A6, 2B6, 2C19, 2C8, 2C9, 2D6, 2E1 and 3A4, which we believe is the largest publicly accessible collection of P450 ligands and metabolites ever released. A comprehensive investigation into the importance of different descriptor classes for predicting the regioselectivity of each isozyme is made through the generation of multiple independent RS-Predictor models for each set of isozyme substrates. Two of these models include a DFT reactivity descriptor derived from SMARTCyp. Optimal combinations of RS-Predictor and SMARTCyp are shown to have stronger performance than either method alone, while also exceeding the accuracy of the commercial regioselectivity prediction methods distributed by StarDrop and Schrödinger, correctly identifying a large proportion of the metabolites in each substrate set within the top two rank-positions: 1A2(83.0%), 2A6(85.7%), 2B6(82.1%), 2C19(86.2%), 2C8(83.8%), 2C9(84.5%), 2D6(85.9%), 2E1(82.8%), 3A4(82.3%) and merged(86.0%). Comprehensive datamining of each substrate set and careful statistical analyses of the predictions made by the different models revealed new insights into molecular features that control metabolic regioselectivity and enable accurate prospective prediction of likely SOMs. PMID:22524152

  11. Plastid Localization of the Key Carotenoid Enzyme Phytoene Synthase Is Altered by Isozyme, Allelic Variation, and Activity[W

    PubMed Central

    Shumskaya, Maria; Bradbury, Louis M.T.; Monaco, Regina R.; Wurtzel, Eleanore T.

    2012-01-01

    Plant carotenoids have unique physiological roles related to specific plastid suborganellar locations. Carotenoid metabolic engineering could enhance plant adaptation to climate change and improve food security and nutritional value. However, lack of fundamental knowledge on carotenoid pathway localization limits targeted engineering. Phytoene synthase (PSY), a major rate-controlling carotenoid enzyme, is represented by multiple isozymes residing at unknown plastid sites. In maize (Zea mays), the three isozymes were transiently expressed and found either in plastoglobuli or in stroma and thylakoid membranes. PSY1, with one to two residue modifications of naturally occurring functional variants, exhibited altered localization, associated with distorted plastid shape and formation of a fibril phenotype. Mutating the active site of the enzyme reversed this phenotype. Discovery of differential PSY locations, linked with activity and isozyme type, advances the engineering potential for modifying carotenoid biosynthesis. PMID:23023170

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

    PubMed

    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. PMID:18096698

  13. Mechanism of Thermal Adaptation in the Lactate Dehydrogenases.

    PubMed

    Peng, Huo-Lei; Egawa, Tsuyoshi; Chang, Eric; Deng, Hua; Callender, Robert

    2015-12-10

    The mechanism of thermal adaptation of enzyme function at the molecular level is poorly understood but is thought to lie within the structure of the protein or its dynamics. Our previous work on pig heart lactate dehydrogenase (phLDH) has determined very high resolution structures of the active site, via isotope edited IR studies, and has characterized its dynamical nature, via laser-induced temperature jump (T-jump) relaxation spectroscopy on the Michaelis complex. These particular probes are quite powerful at getting at the interplay between structure and dynamics in adaptation. Hence, we extend these studies to the psychrophilic protein cgLDH (Champsocephalus gunnari; 0 °C) and the extreme thermophile tmLDH (Thermotoga maritima LDH; 80 °C) for comparison to the mesophile phLDH (38-39 °C). Instead of the native substrate pyruvate, we utilize oxamate as a nonreactive substrate mimic for experimental reasons. Using isotope edited IR spectroscopy, we find small differences in the substate composition that arise from the detailed bonding patterns of oxamate within the active site of the three proteins; however, we find these differences insufficient to explain the mechanism of thermal adaptation. On the other hand, T-jump studies of reduced β-nicotinamide adenine dinucleotide (NADH) emission reveal that the most important parameter affecting thermal adaptation appears to be enzyme control of the specific kinetics and dynamics of protein motions that lie along the catalytic pathway. The relaxation rate of the motions scale as cgLDH > phLDH > tmLDH in a way that faithfully matches kcat of the three isozymes. PMID:26556099

  14. Origin and evolution of medium chain alcohol dehydrogenases.

    PubMed

    Jörnvall, Hans; Hedlund, Joel; Bergman, Tomas; Kallberg, Yvonne; Cederlund, Ella; Persson, Bengt

    2013-02-25

    Different lines of alcohol dehydrogenases (ADHs) have separate superfamily origins, already recognized but now extended and re-evaluated by re-screening of the latest databank update. The short-chain form (SDR) is still the superfamily with most abundant occurrence, most multiple divergence, most prokaryotic emphasis, and most non-complicated architecture. This pattern is compatible with an early appearance at the time of the emergence of prokaryotic cellular life. The medium-chain form (MDR) is also old but second in terms of all the parameters above, and therefore compatible with a second emergence. However, this step appears seemingly earlier than previously considered, and may indicate sub-stages of early emergences at the increased resolution available from the now greater number of data entries. The Zn-MDR origin constitutes a third stage, possibly compatible with the transition to oxidative conditions on earth. Within all these three lines, repeated enzymogeneses gave the present divergence. MDR-ADH origin(s), at a fourth stage, may also be further resolved in multiple or extended modes, but the classical liver MDR-ADH of the liver type can still be traced to a gene duplication ~550 MYA (million years ago), at the early vertebrate radiation, compatible with the post-eon-shift, "Cambrian explosion". Classes and isozymes correspond to subsequent and recent duplicatory events, respectively. They illustrate a peculiar pattern with functional and emerging evolutionary distinctions between parent and emerging lines, suggesting a parallelism between duplicatory and mutational events, now also visible at separate sub-stages. Combined, all forms show distinctive patterns at different levels and illustrate correlations with global events. They further show that simple molecular observations on patterns, multiplicities and occurrence give much information, suggesting common divergence rules not much disturbed by horizontal gene transfers after the initial origins. PMID

  15. Aldehydes with high and low toxicities inactivate cells by damaging distinct cellular targets.

    PubMed

    Xie, Ming-Zhang; Shoulkamy, Mahmoud I; Salem, Amir M H; Oba, Shunya; Goda, Mizuki; Nakano, Toshiaki; Ide, Hiroshi

    2016-04-01

    Aldehydes are genotoxic and cytotoxic molecules and have received considerable attention for their associations with the pathogenesis of various human diseases. In addition, exposure to anthropogenic aldehydes increases human health risks. The general mechanism of aldehyde toxicity involves adduct formation with biomolecules such as DNA and proteins. Although the genotoxic effects of aldehydes such as mutations and chromosomal aberrations are directly related to DNA damage, the role of DNA damage in the cytotoxic effects of aldehydes is poorly understood because concurrent protein damage by aldehydes has similar effects. In this study, we have analysed how saturated and α,β-unsaturated aldehydes exert cytotoxic effects through DNA and protein damage. Interestingly, DNA repair is essential for alleviating the cytotoxic effect of weakly toxic aldehydes such as saturated aldehydes but not highly toxic aldehydes such as long α,β-unsaturated aldehydes. Thus, highly toxic aldehydes inactivate cells exclusively by protein damage. Our data suggest that DNA interstrand crosslinks, but not DNA-protein crosslinks and DNA double-strand breaks, are the critical cytotoxic DNA damage induced by aldehydes. Further, we show that the depletion of intracellular glutathione and the oxidation of thioredoxin 1 partially account for the DNA damage-independent cytotoxicity of aldehydes. On the basis of these findings, we have proposed a mechanistic model of aldehyde cytotoxicity mediated by DNA and protein damage. PMID:26917342

  16. Protein kinase C in the wood frog, Rana sylvatica: reassessing the tissue-specific regulation of PKC isozymes during freezing

    PubMed Central

    Storey, Kenneth B.

    2014-01-01

    The wood frog, Rana sylvatica, survives whole-body freezing and thawing each winter. The extensive adaptations required at the biochemical level are facilitated by alterations to signaling pathways, including the insulin/Akt and AMPK pathways. Past studies investigating changing tissue-specific patterns of the second messenger IP3 in adapted frogs have suggested important roles for protein kinase C (PKC) in response to stress. In addition to their dependence on second messengers, phosphorylation of three PKC sites by upstream kinases (most notably PDK1) is needed for full PKC activation, according to widely-accepted models. The present study uses phospho-specific immunoblotting to investigate phosphorylation states of PKC—as they relate to distinct tissues, PKC isozymes, and phosphorylation sites—in control and frozen frogs. In contrast to past studies where second messengers of PKC increased during the freezing process, phosphorylation of PKC tended to generally decline in most tissues of frozen frogs. All PKC isozymes and specific phosphorylation sites detected by immunoblotting decreased in phosphorylation levels in hind leg skeletal muscle and hearts of frozen frogs. Most PKC isozymes and specific phosphorylation sites detected in livers and kidneys also declined; the only exceptions were the levels of isozymes/phosphorylation sites detected by the phospho-PKCα/βII (Thr638/641) antibody, which remained unchanged from control to frozen frogs. Changes in brains of frozen frogs were unique; no decreases were observed in the phosphorylation levels of any of the PKC isozymes and/or specific phosphorylation sites detected by immunoblotting. Rather, increases were observed for the levels of isozymes/phosphorylation sites detected by the phospho-PKCα/βII (Thr638/641), phospho-PKCδ (Thr505), and phospho-PKCθ (Thr538) antibodies; all other isozymes/phosphorylation sites detected in brain remained unchanged from control to frozen frogs. The results of this study

  17. Saturation transfer difference NMR studies on substrates and inhibitors of succinic semialdehyde dehydrogenases

    SciTech Connect

    Jaeger, Martin Rothacker, Boris; Ilg, Thomas

    2008-08-01

    Saturation transfer difference (STD) NMR experiments on Escherichia coli and Drosophila melanogaster succinic semialdehyde dehydrogenase (SSADH, EC1.2.1.24) suggest that only the aldehyde forms and not the gem-diol forms of the specific substrate succinic semialdehyde (SSA), of selected aldehyde substrates, and of the inhibitor 3-tolualdehyde bind to these enzymes. Site-directed mutagenesis of the active site cysteine311 to alanine in D. melanogaster SSADH leads to an inactive product binding both SSA aldehyde and gem-diol. Thus, the residue cysteine311 is crucial for their discrimination. STD experiments on SSADH and NAD{sup +}/NADP{sup +} indicate differential affinity in agreement with the respective cosubstrate properties. Epitope mapping by STD points to a strong interaction of the NAD{sup +}/NADP{sup +} adenine H2 proton with SSADH. Adenine H8, nicotinamide H2, H4, and H6 also show STD signals. Saturation transfer to the ribose moieties is limited to the anomeric protons of E. coli SSADH suggesting that the NAD{sup +}/NADP{sup +} adenine and nicotinamide, but not the ribose moieties are important for the binding of the coenzymes.

  18. Changes in myosin isozyme expression during cardiac hypertrophy in hyperthyroid rabbits.

    PubMed

    Seiden, D; Srivatsan, M; Navidad, P A

    1989-01-01

    The myosin isozyme distribution in the left ventricle and in the interventricular septum of rabbits was studied after 3, 7, 11, 14 and 21 days of L-thyroxine (500 micrograms/kg/day) administration. Histochemical procedures were employed to identify V1 and V3 by their Ca2+ ATPase activity and their proportions were quantified through polyacrylamide gel electrophoresis. In the left ventricle, the subepicardium was the first to show the shift from V3 to V1, followed by the subendocardium. The intermediate region became heterogeneous by 11 days and remained so until 21 days. The right subendocardial and the intermediate regions of the interventricular septum were heterogeneous in the normal rabbit and hyperthyroidism resulted in a shift from V3 to V1 in both the right and left subendocardial regions of the septum. Like the left ventricle, the intermediate region of the interventricular septum remained heterogeneous. Localized accumulations of collagen were seen in all regions of the left ventricle and interventricular septum. From these results we conclude that in thyrotoxic myocardial hypertrophy the isozymic shift from V3 to V1 is progressive, region-specific and is directly correlated with the period of hyperthyroidism in the first 2 weeks. Prolonged hyperthyroidism results in localized accumulation of collagen which does not exhibit any regional specificity. PMID:2528881

  19. Archaeal Mo-Containing Glyceraldehyde Oxidoreductase Isozymes Exhibit Diverse Substrate Specificities through Unique Subunit Assemblies

    PubMed Central

    Miyake, Masayuki; Fushinobu, Shinya

    2016-01-01

    Archaea use glycolytic pathways distinct from those found in bacteria and eukaryotes, where unique enzymes catalyze each reaction step. In this study, we isolated three isozymes of glyceraldehyde oxidoreductase (GAOR1, GAOR2 and GAOR3) from the thermoacidophilic archaeon Sulfolobus tokodaii. GAOR1–3 belong to the xanthine oxidoreductase superfamily, and are composed of a molybdo-pyranopterin subunit (L), a flavin subunit (M), and an iron-sulfur subunit (S), forming an LMS hetero-trimer unit. We found that GAOR1 is a tetramer of the STK17810/STK17830/STK17820 hetero-trimer, GAOR2 is a dimer of the STK23390/STK05620/STK05610 hetero-trimer, and GAOR3 is the STK24840/STK05620/STK05610 hetero-trimer. GAOR1–3 exhibited diverse substrate specificities for their electron donors and acceptors, due to their different L-subunits, and probably participate in the non-phosphorylative Entner-Doudoroff glycolytic pathway. We determined the crystal structure of GAOR2, as the first three-dimensional structure of an archaeal molybdenum-containing hydroxylase, to obtain structural insights into their substrate specificities and subunit assemblies. The gene arrangement and the crystal structure suggested that the M/S-complex serves as a structural scaffold for the binding of the L-subunit, to construct the three enzymes with different specificities. Collectively, our findings illustrate a novel principle of a prokaryotic multicomponent isozyme system. PMID:26808202

  20. Isozymic variations in specific and nonspecific esterase and its thermostability in silkworm, Bombyx mori L.

    PubMed

    Patnaik, Bharat Bhusan; Biswas, Tapati Datta; Nayak, Sandeepta Kumar; Saha, A K; Majumdar, M K

    2012-09-01

    Esterase isozymic variations were documented in the haemolymph of developed multivoltine and bivoltine silkworm breeds during unfavorable seed crop seasons of May - September using á- and â- napthylacetate separately to identify specific and nonspecific esterase having thermotolerant potentiality. Variations existed in the isozyme pattern with three bands (Est-2, 3 and 4) in pure Nistari race and other developed multivoltine and bivoltine breeds. Est-2 and Est-3 were non-specific esterases as they were observed when both á- and â-napthylacetate was used as substrates separately. Est-4 band was observed only with á-napthylacetate as substrate and was therefore confirmed to be specific á-esterase band in the haemolymph of silkworm, Bombyx mori L. Zymograms showed that the non-specific esterase band (Est-3) with R1 of 0.43 and specific á-esterase band (Est-4) with R(f) of 0.32 predominately withstood a temperature of 70 +/- 2 degrees C for a duration of 10 min and were confirmed as thermostable esterases in haemolymph of silkworm, Bombyx mori L. This also categorized the presence of thermostable esterases in developed multivoltine and bivoltine breeds of silkworm, even though the qualitative activity was more in the former than the latter. The qualitative presence of thermostable esterases and their activity could be adopted as an indicative biochemical marker in relation to thermotolerance in silkworm. PMID:23734447

  1. Distinct physiological roles for the two L-asparaginase isozymes of Escherichia coli

    SciTech Connect

    Srikhanta, Yogitha N.; Atack, John M.; Beacham, Ifor R.; Jennings, Michael P.

    2013-07-05

    Highlights: •Escherichia coli contains two L-asparaginase isozymes with distinct localization, kinetics and regulation. •Mutant strains were used to examine the roles of these enzymes in L-asparagine utilization. •We report that L-asparaginase II permits growth on asparagine and glycerol under anaerobic conditions. •We propose that this enzyme is the first step in a co-regulated pathway leading to fumarate. •The pathway is regulated by anaerobiosis and cAMP and provides a terminal elector acceptor. -- Abstract: Escherichia coli expresses two L-asparaginase (EC 3.5.1.1) isozymes: L-asparaginse I, which is a low affinity, cytoplasmic enzyme that is expressed constitutively, and L-asparaginase II, a high affinity periplasmic enzyme that is under complex co-transcriptional regulation by both Fnr and Crp. The distinct localisation and regulation of these enzymes suggest different roles. To define these roles, a set of isogenic mutants was constructed that lacked either or both enzymes. Evidence is provided that L-asparaginase II, in contrast to L-asparaginase I, can be used in the provision of an anaerobic electron acceptor when using a non-fermentable carbon source in the presence of excess nitrogen.

  2. Adenylate kinase isozyme 2 is essential for growth and development of Drosophila melanogaster.

    PubMed

    Fujisawa, Koichi; Murakami, Ryutaro; Horiguchi, Taigo; Noma, Takafumi

    2009-05-01

    Adenylate kinases are phylogenetically widespread, highly conserved, and involved in energy metabolism and energy transfer. Of these, adenylate kinase (AK) isozyme 2 is uniquely localized in the mitochondrial intermembrane space and its physiological role remains largely unknown. In this study, we selected Drosophila melanogaster to analyze its role in vivo. AK isozyme cDNAs were cloned and their gene expressions were characterized in D. melanogaster. The deduced amino acid sequences contain highly conserved motifs for P-loop, NMP binding, and LID domains of AKs. In addition, the effects of AK2 gene knockout on phenotype of AK2 mutants were examined using P-element technology. Although homozygous AK2 mutated embryos developed without any visible defects, their growth ceased and they died before reaching the third instar larval stage. Maternally provided AK2 mRNA was detected in fertilized eggs, and weak AK2 activity was observed in first and second instar larvae of the homozygous AK2 mutants, suggesting that maternally provided AK2 is sufficient for embryonic development. Disappearance of AK2 activity during larval stages resulted in growth arrest and eventual death. These results demonstrate that AK2 plays a critical role in adenine nucleotide metabolism in the mitochondrial intermembrane space and is essential for growth in D. melanogaster. PMID:19416704

  3. Studies on isozymic variation among the South Indian species of Sphaerostephanos

    PubMed Central

    Varaprasadham, Irudayaraj; Marimuthu, Johnson

    2011-01-01

    Objective To explore the identity and phylogenetic relationships among the three medicinally important species of Sphaerostephanos from South India using isozymic profile. Methods The young fronds were homogenized with 3.5 mL of ice-cold homogenizing buffer in a pre-chilled pestle and mortar. The supernatant was subjected to electrophoresis as described by Anbalagan poly acrylamide gel electrophoresis. Staining solutions for isoperoxidase was prepared as per Smila method for the detection of isoenzymes. Results A total of six different bands in five different positions with different molecular weight/Rf values and four active zones have been observed in the isoperoxidase enzyme system of Sphaerostephanos. Only one band with MW/Rf 0.399 is common to two different species i.e. Sphaerostephanos arbuscula (S. arbuscula) and Sphaerostephanos unitus (S. unitus). Among the remaining four bands, two bands (Rf. 0.23, 0.47) are present in Sphaerostephanos subtruncatus (S. subtruncatus) and one distinct band has been observed individually in S. arbuscula (Rf. 0.507) and S. unitus (Rf. 0.56). Conclusions The present preliminary molecular study through isozymic analysis shows the identity of all the three species and the present results confirm distinctness of these three species based on macro-micromorphology, phytochemistry and cytology. PMID:23569778

  4. Role of PKC isozymes in low-power light-stimulated proliferation of cultured skin cells

    NASA Astrophysics Data System (ADS)

    Grossman, Nili; Kleitman, Vered; Meller, Julia; Kaufmann, Roland; Akgun, Nermin; Ruck, Angelika; Livneh, Etta; Lubart, Rachel

    2000-11-01

    Exposure of cultured skin cells to low power visible light leads to a transiently stimulated proliferation. Facilitation of this response requires the presence of active PKC, elevation of intracellular calcium, and involves reactive oxygen species. In the present study, the role of PKC(alpha) and PCK(eta) was examined using paired murine fibroblasts, differing in the level of these isozymes expression. The ability of the cells to respond to low power UVA light or HeNe laser by stimulated proliferation was correlated with an active state or overexpression of PKC(alpha) , but not PKC(eta) . A parallel response was obtained in cells that were loaded with A1PcS4 before photosensitization. Whenever this latter treatment caused a light-stimulated inhibition, it was accompanied by the intracellular calcium and photosensitizer dynamics typical of the effect of PDT on rate epithelial cells. Accordingly, added antioxidants that suppressed light-stimulated proliferation also suppressed this light-stimulated inhibition. The model systems employed in this study are the first to demonstrate the specific effect of PKC isozymes on light-stimulated proliferation, in relation to oxidative stress, and indicate their dual role in light-tissue interaction.

  5. Archaeal Mo-Containing Glyceraldehyde Oxidoreductase Isozymes Exhibit Diverse Substrate Specificities through Unique Subunit Assemblies.

    PubMed

    Wakagi, Takayoshi; Nishimasu, Hiroshi; Miyake, Masayuki; Fushinobu, Shinya

    2016-01-01

    Archaea use glycolytic pathways distinct from those found in bacteria and eukaryotes, where unique enzymes catalyze each reaction step. In this study, we isolated three isozymes of glyceraldehyde oxidoreductase (GAOR1, GAOR2 and GAOR3) from the thermoacidophilic archaeon Sulfolobus tokodaii. GAOR1-3 belong to the xanthine oxidoreductase superfamily, and are composed of a molybdo-pyranopterin subunit (L), a flavin subunit (M), and an iron-sulfur subunit (S), forming an LMS hetero-trimer unit. We found that GAOR1 is a tetramer of the STK17810/STK17830/STK17820 hetero-trimer, GAOR2 is a dimer of the STK23390/STK05620/STK05610 hetero-trimer, and GAOR3 is the STK24840/STK05620/STK05610 hetero-trimer. GAOR1-3 exhibited diverse substrate specificities for their electron donors and acceptors, due to their different L-subunits, and probably participate in the non-phosphorylative Entner-Doudoroff glycolytic pathway. We determined the crystal structure of GAOR2, as the first three-dimensional structure of an archaeal molybdenum-containing hydroxylase, to obtain structural insights into their substrate specificities and subunit assemblies. The gene arrangement and the crystal structure suggested that the M/S-complex serves as a structural scaffold for the binding of the L-subunit, to construct the three enzymes with different specificities. Collectively, our findings illustrate a novel principle of a prokaryotic multicomponent isozyme system. PMID:26808202

  6. Soybean roots retain the seed urease isozyme synthesized during embryo development

    SciTech Connect

    Torisky, R.S.; Polacco, J.C. )

    1990-05-01

    Roots of young soybean plants contain two urease isozymes which are separable by hydroxyapatite chromatography. These two urease species (HAP1 and HAP2) differ in: (1) native gel electrophoretic mobility, (2) pH optima, and (3) recognition by a monoclonal antibody specific for the embryo-specific urease. By these parameters HAP1 is similar to the abundant embryo-specific urease isozyme while HAP2 resembles the ubiquitous urease, found in all soybean tissues previously examined (embryo, seed coat, cultured cells). Roots of mutant soybean plants lacking the seed urease contain no HAP1 urease activity, whereas roots of mutants lacking the ubiquitous urease contain no HAP2 urease activity. However, adventitious roots generated from cuttings of any urease genotype lack HAP1 urease activity. Furthermore, ({sup 35}S) methionine labelling shows no {und de novo} synthesis of the HAP1 urease in the root, and total root HAP1 urease activity decreases sharply following germination. We conclude: (1) HAP1 is a remnant of the seed urease accumulated in the embryonic root axis during seed development, and (2) HAP2 is ubiquitous urease synthesized de novo in the root.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

    Seman-Kamarulzaman, Ahmad-Faris; Mohamed-Hussein, Zeti-Azura; Ng, Chyan Leong; Hassan, Maizom

    2016-01-01

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

  9. Reaction of tobacco smoke aldehydes with human hemoglobin.

    PubMed

    Hoberman, H D; San George, R C

    1988-01-01

    Formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, and acrolein, all of which are constituents of tobacco smoke, were reacted in 5 mM concentration with the purified major fraction of normal adult human hemoglobin (hemoglobin Ao) in 1 mM concentration. A cigarette smoke condensate, diluted to contain 5 mM total aldehydes, was also reacted with 1 mM hemoglobin Ao. Cationic exchange high-performance liquid chromatography (HPLC) showed that the products formed from simple aliphatic aldehydes, with the exception of formaldehyde, were analogues of those formed from acetaldehyde, earlier shown by us to be imidazolidinone derivatives, that is, cyclic addition products of the N-terminal aminoamide function of alpha and beta chains. Formaldehyde and acrolein produced a heterogeneous mixture of derivatives including cross-linked hemoglobin dimers. The greater proportion of modified hemoglobins produced by condensate aldehydes resembled those formed from acetaldehyde, the most abundant aldehyde in the condensate. A smaller fraction consisted of cross-linked hemoglobin dimers, presumably due to the action of formaldehyde. Mass spectrometric and HPLC analyses of the 2,4-dinitrophenylhydrazones precipitated from the condensate documented the presence of formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, furfural, and methylfurfural. The toxicity of aldehydes is briefly discussed in the context of the findings of this study. PMID:3236330

  10. Aldehydes: occurrence, carcinogenic potential, mechanism of action and risk assessment.

    PubMed

    Feron, V J; Til, H P; de Vrijer, F; Woutersen, R A; Cassee, F R; van Bladeren, P J

    1991-01-01

    Aldehydes constitute a group of relatively reactive organic compounds. They occur as natural (flavoring) constituents in a wide variety of foods and food components, often in relatively small, but occasionally in very large concentrations, and are also widely used as food additives. Evidence of carcinogenic potential in experimental animals is convincing for formaldehyde and acetaldehyde, limited for crotonaldehyde, furfural and glycidaldehyde, doubtful for malondialdehyde, very weak for acrolein and absent for vanillin. Formaldehyde carcinogenesis is a high-dose phenomenon in which the cytotoxicity plays a crucial role. Cytotoxicity may also be of major importance in acetaldehyde carcinogenesis but further studies are needed to prove or disprove this assumption. For a large number of aldehydes (relevant) data on neither carcinogenicity nor genotoxicity are available. From epidemiological studies there is no convincing evidence of aldehyde exposure being related to cancer in humans. Overall assessment of the cancer risk of aldehydes in the diet leads to the conclusion that formaldehyde, acrolein, citral and vanillin are no dietary risk factors, and that the opposite may be true for acetaldehyde, crotonaldehyde and furfural. Malondialdehyde, glycidaldehyde, benzaldehyde, cinnamaldehyde and anisaldehyde cannot be evaluated on the basis of the available data. A series of aldehydes should be subjected to at least mutagenicity, cytogenicity and cytotoxicity tests. Priority setting for testing should be based on expected mechanism of action and degree of human exposure. PMID:2017217

  11. Hypoxically inducible barley lactate dehydrogenase: cDNA cloning and molecular analysis

    SciTech Connect

    Hondred, D. ); Hanson, A.D. Univ. de Montreal, Quebec )

    1990-09-01

    In the roots of barley and other cereals, hypoxia induces a set of five isozymes of L-lactate dehydrogenase (LDH; (S)-lactate:NADH oxidoreductase, EC 1.1.1.27). Biochemical and genetic data indicate that the five LDH isozymes are tetramers that arise from random association of the products of two Ldh loci. To investigate this system, cDNA clones of LDH were isolated from a {lambda}gt11 cDNA library derived from hypoxically treated barley roots. The library was screened with antiserum raised against barley LDH purified {approx}3,000-fold by an improved three-step procedure. Immunopositive clones were rescreened with a cDNA probe synthesized by the polymerase chain reaction using primers modeled from the amino acid sequences of two tryptic LDH peptides. Two types of LDH clones were found. Nucleotide sequence analysis of one representative insert of each type (respectively, 1,305 and 1,166 base pairs) revealed open reading framed encoding 10 peptide fragments of LDH. The 1,305-base-pair insert included the entire coding region of a 356-residue LDH monomer. The nucleotide sequences of the two LDH cDNAs were 92% identical in the coding region, but highly divergent in the 3{prime} noncoding region, and thus probably correspond to the two postulated Ldh loci. The deduced amino acid sequences of the two barley LDHs were 96% identical to each other and very similar to those from vertebrate and bacterial LDHs. RNA blot hybridization showed a single mRNA band of 1.5 kilobases whose level rose about 8-fold in roots during hypoxic induction, as did the level of translatable LDH message.

  12. Characterization of a new liver- and kidney-specific pfkfb3 isozyme that is downregulated by cell proliferation and dedifferentiation

    SciTech Connect

    Duran, Joan; Gomez, Marta; Navarro-Sabate, Aurea; Riera-Sans, Lluis; Obach, Merce; Manzano, Anna; Perales, Jose C.; Bartrons, Ramon

    2008-03-21

    The bifunctional enzyme 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase (PFK-2) catalyzes the synthesis and degradation of fructose 2,6-bisphosphate (Fru-2,6-P{sub 2}), a signalling molecule that controls the balance between glycolysis and gluconeogenesis in several cell types. Four genes, designated Pfkfb1-4, code several PFK-2 isozymes that differ in their kinetic properties, molecular masses, and regulation by protein kinases. In rat tissues, Pfkfb3 gene accounts for eight splice variants and two of them, ubiquitous and inducible PFK-2 isozymes, have been extensively studied and related to cell proliferation and tumour metabolism. Here, we characterize a new kidney- and liver-specific Pfkfb3 isozyme, a product of the RB2K3 splice variant, and demonstrate that its expression, in primary cultured hepatocytes, depends on hepatic cell proliferation and dedifferentiation. In parallel, our results provide further evidence that ubiquitous PFK-2 is a crucial isozyme in supporting growing and proliferant cell metabolism.

  13. Involvement of Peroxidase and Indole-3-acetic Acid Oxidase Isozymes from Pear, Tomato, and Blueberry Fruit in Ripening

    PubMed Central

    Frenkel, Chaim

    1972-01-01

    Protein extracts were obtained from climacteric fruits (pear, tomato) and nonclimacteric fruits (blueberry) during various stages of ripening. The use of a gel electrophoresis technique revealed a consistent reinforcement in indoleacetic acid oxidase but not in peroxidase isozymes during ripening. The significance of the results is discussed in relation to the resistance of fruits to ripening and ethylene action. Images PMID:16658043

  14. Penicillium solitum produces a polygalacturonase isozyme in decayed ‘Anjou’ pear fruit capable of macerating host tissue in vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A polygalacturonase (PG) isozyme was isolated from Penicillium solitum-decayed ‘Anjou’ pear fruit and purified to homogeneity using a multistep process. Both gel filtration and cation exchange chromatography revealed a single PG activity peak and analysis of the purified protein showed a single band...

  15. Increased Clearance of Reactive Aldehydes and Damaged Proteins in Hypertension-Induced Compensated Cardiac Hypertrophy: Impact of Exercise Training

    PubMed Central

    Campos, Juliane Cruz; Fernandes, Tiago; Bechara, Luiz Roberto Grassmann; da Paixão, Nathalie Alves; Brum, Patricia Chakur; de Oliveira, Edilamar Menezes; Ferreira, Julio Cesar Batista

    2015-01-01

    Background. We previously reported that exercise training (ET) facilitates the clearance of damaged proteins in heart failure. Here, we characterized the impact of ET on cardiac protein quality control during compensated ventricular hypertrophy in spontaneously hypertensive rats (SHR). Methods and Results. SHR were randomly assigned into sedentary and swimming-trained groups. Sedentary SHR displayed cardiac hypertrophy with preserved ventricular function compared to normotensive rats, characterizing a compensated cardiac hypertrophy. Hypertensive rats presented signs of cardiac oxidative stress, depicted by increased lipid peroxidation. However, these changes were not followed by accumulation of lipid peroxidation-generated reactive aldehydes and damaged proteins. This scenario was explained, at least in part, by the increased catalytic activity of both aldehyde dehydrogenase 2 (ALDH2) and proteasome. Of interest, ET exacerbated cardiac hypertrophy, improved ventricular function, induced resting bradycardia, and decreased blood pressure in SHR. These changes were accompanied by reduced cardiac oxidative stress and a consequent decrease in ALDH2 and proteasome activities, without affecting small chaperones levels and apoptosis in SHR. Conclusion. Increased cardiac ALDH2 and proteasomal activities counteract the deleterious effect of excessive oxidative stress in hypertension-induced compensated cardiac hypertrophy in rats. ET has a positive effect in reducing cardiac oxidative stress without affecting protein quality control. PMID:25954323

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

    PubMed

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

    2004-08-01

    Metabolism of aromatic amino acids by lactic acid bacteria is an important source of off-flavor compounds in Cheddar cheese. Previous work has shown that alpha-keto acids produced from Trp, Tyr, and Phe by aminotransferase enzymes are chemically labile and may degrade spontaneously into a variety of off-flavor compounds. However, dairy lactobacilli can convert unstable alpha-keto acids to more-stable alpha-hydroxy acids via the action of alpha-keto acid dehydrogenases such as d-hydroxyisocaproic acid dehydrogenase. To further characterize the role of this enzyme in cheese flavor, the Lactobacillus casei d-hydroxyisocaproic acid dehydrogenase gene was cloned into the high-copy-number vector pTRKH2 and transformed into L. casei ATCC 334. Enzyme assays confirmed that alpha-keto acid dehydrogenase activity was significantly higher in pTRKH2:dhic transformants than in wild-type cells. Reduced-fat Cheddar cheeses were made with Lactococcus lactis starter only, starter plus L. casei ATCC 334, and starter plus L. casei ATCC 334 transformed with pTRKH2:dhic. After 3 months of aging, the cheese chemistry and flavor attributes were evaluated instrumentally by gas chromatography-mass spectrometry and by descriptive sensory analysis. The culture system used significantly affected the concentrations of various ketones, aldehydes, alcohols, and esters and one sulfur compound in cheese. Results further indicated that enhanced expression of d-hydroxyisocaproic acid dehydrogenase suppressed spontaneous degradation of alpha-keto acids, but sensory work indicated that this effect retarded cheese flavor development. PMID:15294819

  17. Polyvinyl alcohol cross-linked with two aldehydes

    NASA Technical Reports Server (NTRS)

    Sheibley, D. W.; Rieker, L. L.; Hsu, L. C.; Manzo, M. A. (Inventor)

    1982-01-01

    A film forming polyvinyl alcohol resin is admixed, in aqueous solution, with a dialdehyde crosslinking agent which is capable of crosslinking the polyvinyl alcohol resin and a water soluble acid aldehyde containing a reactive aldehyde group capable of reacting with hydroxyl groups in the polyvinyl alcohol resin and an ionizable acid hydrogen atom. The dialdehyde is present in an amount sufficient to react with from 1 to 20% by weight of the theoretical amount required to react with all of the hydroxyl groups of the polyvinyl alcohol. The amount of acid aldehyde is from 1 to 50% by weight, same basis, and is sufficient to reduce the pH of the aqueous admixture to 5 or less. The admixture is then formed into a desired physical shape, such as by casting a sheet or film, and the shaped material is then heated to simultaneously dry and crosslink the article.

  18. Formaldehyde dehydrogenase preparations from Methylococcus capsulatus (Bath) comprise methanol dehydrogenase and methylene tetrahydromethanopterin dehydrogenase.

    PubMed

    Adeosun, Ekundayo K; Smith, Thomas J; Hoberg, Anne-Mette; Velarde, Giles; Ford, Robert; Dalton, Howard

    2004-03-01

    In methylotrophic bacteria, formaldehyde is an important but potentially toxic metabolic intermediate that can be assimilated into biomass or oxidized to yield energy. Previously reported was the purification of an NAD(P)(+)-dependent formaldehyde dehydrogenase (FDH) from the obligate methane-oxidizing methylotroph Methylococcus capsulatus (Bath), presumably important in formaldehyde oxidation, which required a heat-stable factor (known as the modifin) for FDH activity. Here, the major protein component of this FDH preparation was shown by biophysical techniques to comprise subunits of 64 and 8 kDa in an alpha(2)beta(2) arrangement. N-terminal sequencing of the subunits of FDH, together with enzymological characterization, showed that the alpha(2)beta(2) tetramer was a quinoprotein methanol dehydrogenase of the type found in other methylotrophs. The FDH preparations were shown to contain a highly active NAD(P)(+)-dependent methylene tetrahydromethanopterin dehydrogenase that was the probable source of the NAD(P)(+)-dependent formaldehyde oxidation activity. These results support previous findings that methylotrophs possess multiple pathways for formaldehyde dissimilation. PMID:14993320

  19. Initial-rate kinetics of human NMN-adenylyltransferases: substrate and metal ion specificity, inhibition by products and multisubstrate analogues, and isozyme contributions to NAD+ biosynthesis.

    PubMed

    Sorci, Leonardo; Cimadamore, Flavio; Scotti, Stefania; Petrelli, Riccardo; Cappellacci, Loredana; Franchetti, Palmarisa; Orsomando, Giuseppe; Magni, Giulio

    2007-04-24

    Initial-rate and product inhibition studies revealed distinctive ordered ternary complex kinetic mechanisms, substrate specificities, and metal ion preferences for the three isozymes of human nicotinamide mononucleotide adenylyl-transferase (NMNAT, EC 2.7.7.1). ATP binds before NMN with nuclear isozyme NMNAT1 and Golgi apparatus NMNAT2, but the opposite order is observed with the mitochondrial isozyme NMNAT3. Only the latter utilizes ITP efficiently in place of ATP, and while NMNH conversion to NADH by NMNAT1 and NMNAT3 occurs at similar rates, conversion by NMNAT2 is much slower. These isozymes can also be discriminated by their action on tiazofurin monophosphate (TrMP), a metabolite of the antineoplastic prodrug tiazofurin. Our finding that TrMP is only a substrate with NMNAT1 and NMNAT3 reveals for the first time an organelle selectivity in the metabolism of this important drug. In search of additional ways to discriminate these isozymes, we synthesized and tested the P1-(nicotinamide/nicotinate-riboside-5')-Pn-(adenosine-5') dinucleotides Np3AD, Np4AD, and Nap4AD. In addition to being highly effective inhibitors, these multisubstrate geometric inhibitors gave inhibition patterns that are consistent with the aforementioned isozyme differences in substrate binding order. Distinctive differences in their substrate specificity and metal ion selectivity also permitted us to quantify individual isozyme contributions to NAD+ formation in human cell extracts. PMID:17402747

  20. Immunohistochemical study of temporal variations in cytochrome P-450 isozymes in rat testis and their modifications by the inductive effects of cadinenes

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yasuhito; Motohashi, Yutaka; Miyazaki, Yoshifumi; Yatagai, Mitsuyoshi; Takano, Takehito

    1991-12-01

    Temporal variations in cytochrome P-450 isozymes of rat testis, PB-P-450 (forms of cytochrome P-450 strongly induced by phenobarbital) and MC-P-448 (forms of cytochrome P-450 strongly induced by 3-methylcholanthrene), were investigated immunohistochemically by the avidin-biotin-complex method using specific antibodies against PB-P-450 and MC-P-448 isozymes. Immunoreactivity to both PB-P-450 and MC-P-448 isozymes was observed in Leydig cells. The number of PB-P-450 positive Leydig cells was found to undergo significant time-of-day variation with a peak time of 0000 hours (light phase from 0800 to 2000 hours). Injection of cadinenes (300 mg/kg per day intraperitoneally at 48 and 96 h before sacrifice) induced PB-P-450 isozyme but did not induce MC-P-448 isozyme. The induction of PB-P-450 isozyme by cadinenes was time dependent, and the early dark phase (2000 and 0000 hours) was most sensitive. These results suggest that temporal variation of cytochrome P-450 isozymes is one of the important physiological variations in detoxification and activation of various xenobiotics and chemicals in the testis.

  1. Inhibitors of cyclic nucleotide phosphodiesterase isozymes type-III and type-IV suppress mitogenesis of rat mesangial cells.

    PubMed Central

    Matousovic, K; Grande, J P; Chini, C C; Chini, E N; Dousa, T P

    1995-01-01

    We studied interactions between the mitogen-activated protein kinase (MAPK) signalling pathway and cAMP-protein kinase (PKA) signaling pathway in regulation of mitogenesis of mesangial cells (MC) determined by [3H]thymidine incorporation, with or without added EGF. Forskolin or dibutyryl cAMP strongly (by 60-70%) inhibited [3H]thymidine incorporation into MC. Cilostamide, lixazinone or cilostazol selective inhibitors of cAMP-phosphodiesterase (PDE) isozyme PDE-III, inhibited mitogenesis to similar extent as forskolin and DBcAMP and activated in situ PKA, but without detectable increase in cAMP levels. Cilostamide and cilostazol were more than three times more effective at inhibiting mesangial mitogenesis than rolipram and denbufylline, inhibitors of isozyme PDE-IV, even though PDE-IV was two times more abundant in MC than was PDE-III. On the other hand, when incubated with forskolin, rolipram-enhanced cAMP accumulation was far greater (10-100x) than with cilostamide. EGF increased MAPK activity (+300%); PDE isozyme inhibitors which suppressed mitogenesis also inhibited MAPK. PDE isozyme inhibitors also suppressed PDGF-stimulated MC proliferation. We conclude that cAMP inhibits the mitogen-dependent MAPK-signaling pathway probably by decreasing the activity of Raf-1 due to PKA-catalyzed phosphorylation. Further, we surmise that minor increase in the cAMP pool metabolized by PDE-III is intimately related to regulation of mesangial proliferation. Thus, PDE isozyme inhibitors have the potential to suppress MC proliferation by a focused effect upon signaling pathways. Images PMID:7615811

  2. Direct β-Alkylation of Aldehydes via Photoredox Organocatalysis

    PubMed Central

    2015-01-01

    Direct β-alkylation of saturated aldehydes has been accomplished by synergistically combining photoredox catalysis and organocatalysis. Photon-induced enamine oxidation provides an activated β-enaminyl radical intermediate, which readily combines with a wide range of Michael acceptors to produce β-alkyl aldehydes in a highly efficient manner. Furthermore, this redox-neutral, atom-economical C–H functionalization protocol can be achieved both inter- and intramolecularly. Mechanistic studies by various spectroscopic methods suggest that a reductive quenching pathway is operable. PMID:24754456

  3. Expression, purification and preliminary crystallographic studies of alpha-amylase isozyme 1 from barley seeds.

    PubMed

    Robert, Xavier; Gottschalk, Tine E; Haser, Richard; Svensson, Birte; Aghajari, Nushin

    2002-04-01

    The germinating barley seed contains two major alpha-amylase isozyme families, AMY1 and AMY2, involved in starch degradation to provide energy used by the plant embryo for growth. Many years of difficulty in growing three-dimensional crystals of natural AMY1 have now been overcome by a nonapeptide truncation of the enzyme C-terminus. The truncated enzyme was overexpressed in Pichia pastoris, purified and crystallized by the hanging-drop vapour-diffusion method using polyethylene glycol 8000 as precipitant and 2-propanol as an additive. Crystals belong to the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 88.36, b = 72.82, c = 61.74 A and one molecule per asymmetric unit. PMID:11914496

  4. Effects of calcium ion concentration on starch hydrolysis of barley alpha-amylase isozymes.

    PubMed

    Yuk, Jeong-Bin; Choi, Seung-Ho; Lee, Tae-Hee; Jang, Myoung-Uoon; Park, Jung-Mi; Yi, Ah-Rum; Svensson, Birte; Kim, Tae-Jip

    2008-04-01

    Barley alpha-amylase genes, amy1 and amy2, were separately cloned into the expression vector of pPICZalphaA and recombinant Pichia strains were established by homologous recombination. Both AMYs from Pichia shared almost identical hydrolysis patterns on short maltooligosaccharides to result in glucose, maltose, or maltotriose. Against insoluble blue starch, AMY1 showed the highest activity at 0.1-5 mM calcium concentration, whereas 15-20 mM was optimal for AMY2. On the hydrolysis of soluble starch, unexpectedly, there was no significant difference between AMYs with increase of calcium. However, the relative activity on various starch substrates was significantly different between AMYs, which supports that the isozymes are clearly distinguished from each other on the basis of their unique preferences for substrates. PMID:18467868

  5. Distinct physiological roles for the two L-asparaginase isozymes of Escherichia coli.

    PubMed

    Srikhanta, Yogitha N; Atack, John M; Beacham, Ifor R; Jennings, Michael P

    2013-07-01

    Escherichia coli expresses two L-asparaginase (EC 3.5.1.1) isozymes: L-asparaginse I, which is a low affinity, cytoplasmic enzyme that is expressed constitutively, and L-asparaginase II, a high affinity periplasmic enzyme that is under complex co-transcriptional regulation by both Fnr and Crp. The distinct localisation and regulation of these enzymes suggest different roles. To define these roles, a set of isogenic mutants was constructed that lacked either or both enzymes. Evidence is provided that L-asparaginase II, in contrast to L-asparaginase I, can be used in the provision of an anaerobic electron acceptor when using a non-fermentable carbon source in the presence of excess nitrogen. PMID:23726917

  6. Carbonic Anhydrase Interaction With Lipothioars Enites: A Novel Class of Isozymes I and II Inhibitors

    PubMed Central

    Timotheatou, Despina; Ioannou, Panayiotis V.; Scozzafava, Andrea; Briganti, Fabrizio

    1996-01-01

    The interaction of carbonic anhydrase (CA) isozymes I and II with a series of As(III) derivatives, dialkyl and diaryl rac-2,3-dimyristoyloxypropyldithioarsonites, was investigated kinetically and spectrophotometrically, utilizing the native and Co(II)-substituted enzymes. Depending on the substitution pattern at the -As(SR)2 moiety of the investigated derivatives, inactive compounds were found for R = phenyl or naphthyl, and active ones for derivatives containing carboxyl groups (R = CH2COOH, cysteinyl and glutathionyl). Together with the arsonolipids previously investigated, the active compounds of this series - the "lipothioarsenites"- constitute a novel class of CA inhibitors that bind to the metal ion within the enzyme active site, as proved by changes in the electronic spectra of adducts of such inhibitors with Co(II)CA. PMID:18475756

  7. Post-Transcriptional Regulation of Catalase Isozyme Expression in Cotton Seeds.

    PubMed Central

    Ni, W; Trelease, RN

    1991-01-01

    We reported previously that expression of the five tetrameric catalase isozymes during postgerminative growth of cotton seedings was a consequence of interactions between two subunits (SU 1 and SU 2) temporally synthesized from two distinct catalase genes. In this study, we focused on the regulation of the expression of these two catalase subunits during the changeover from glyoxysomal to leaf-type peroxisomal metabolism. The steady-state level of glyoxysomal SU 1 protein (present in 12-hour-old seeds) increased through day 3 and then declined linearly through day 6, whereas SU 2 protein (first detected in 24-hour-old seeds) increased continuously through day 6. The time courses for steady-state levels of the mRNAs encoding these two subunits revealed two clearly separated peaks: the first at day 1 (SU 1) and the other at day 4 (SU 2). Accumulation of these mRNAs preceded the accumulation of their corresponding proteins by at least 24 hours, suggesting temporal, pretranslational regulation of synthesis of both subunits. Results from run-on transcriptional assays with isolated nuclei, however, revealed that transcripts encoding both subunits were synthesized together on days 1 through 5. Hence, it appears that the accumulations of SU 1 and SU 2 mRNAs are controlled primarily at the post-transcriptional level, which has not been reported for catalase or any other eukaryotic peroxisomal enzymes. The accumulation of SU 1 mRNA is not light dependent, whereas the accumulation of SU 2 mRNA, which directs synthesis of the predominant subunit comprising the leaf-type peroxisomal isozyme, occurs only after exposure of seedlings to light. PMID:12324611

  8. Carbonic anhydrase in Tectona grandis: kinetics, stability, isozyme analysis and relationship with photosynthesis.

    PubMed

    Tiwari, Anita; Kumar, Pramod; Chawhaan, Pravin H; Singh, Sanjay; Ansari, S A

    2006-08-01

    Carbonic anhydrase (CA, EC: 4.2.1.1) activity in teak (Tectona grandis L.f.) was studied to determine its characteristics, kinetics and isozyme patterns. We also investigated effects of leaf age, plant age and genotype on CA activity and gas exchange parameters. Carbonic anhydrase extracted from leaves in 12 mM veronal buffer, pH 7.8, had a K(m) for CO(2) of 15.20 mM and a V(max) of 35,448 U mg(-1) chlorophyll min(-1), which values declined by 50 and 70%, respectively, after 1 week of storage at 4 degrees C. A 15% native polyacrylamide gel revealed the absence of CA isozymes in teak, with only a single CA band of 45 kD molecular mass observed across 10 segregating half-sib families and groups of trees ranging in age from 10 to 25 years. Activity remained stable during the first month in storage at 0 degrees C, but gradually declined to 25% of the initial value after 1 year in storage. During the period of active growth (February-May), maximal CA activity was observed in fully expanded and illuminated leaves. Significant variation was observed in CA activity across 10 1-year-old half-sib families and 21 5-year-old half-sib families. There was a positive correlation between CA activity and photosynthetic rate in a population of 10-year-old trees (P < 0.005). Positive correlations between CA activity and photosynthetic rate were found in 10 of 21 5-year-old half-sib families (P < 0.005 to P < 0.05), which showed greater diversity in CA activity than in photosynthetic characteristics. Thus, CA may serve as a biochemical marker for photosynthetic capacity in teak genotypes. PMID:16651256

  9. Biochemical properties of duplicated isozymes of phosphoglucose isomerase in the plant Clarkia xantiana.

    PubMed

    Gottlieb, L D; Greve, L C

    1981-02-01

    The structural gene locus specifying subunits of cytoplasmic isoenzymes of phosphoglucose isomerase (PGI) is present in duplicate in many diploid species of Clarkia (Onagraceae), a genus of annual plants native to California. We studied the kinetic properties and molecular weights of a large number of genetically defined and highly purified PGIs in C. xantiana, a number of species with the duplication, as a means of examining the biochemical consequences of the evolution of a new gene locus. This species is primarily outcrossing, but also includes several previously described predominantly self-pollinating populations. Both cytoplasmic PGI loci in the outcrossing populations are polymorphic and their enzyme products are readily separated by electrophoresis. The PGIs from the outcrossing populations were rated by electrophoresis. The PGIs from the outcrossing populations were generally closely similar in molecular weight, pH optimum, heat sensitivity, energy activation, and apparent Km (fructose-6-phosphate). The PGI loci in the selfing populations are monomorphic and specify enzymes having identical electrophoretic mobilities to those coded by the most frequent alleles of the outcrosser. The PGI isozymes in the selfers differed fivefold in Km, suggesting that they have a very different catalytic effectiveness. The high Km of the PGI-3A' isozyme (1.1mM) was anomalous among the PGIs examined and would likely be disadvantageous in a species which lacked other more normally functioning PGIs. But in the cytoplasm of the selfing plants, it is present with other PGIs that have low Km values. The PGI-3A' enzyme is a good candidate for a gene product coded by a "forbidden" mutation that could not have been established in the absence of the duplication. The rationale for this suggestion is described and it is also pointed out that the divergence of duplicated genes is influenced by many factors such as the breeding system and other population factors as well as the effect of

  10. The aromatic alcohol dehydrogenases in Pseudomonas putida N.C.I.B. 9869 grown on 3,5-xylenol and p-cresol.

    PubMed Central

    Keat, M J; Hopper, D J

    1978-01-01

    Whole cells of Pseudomonas putida N.C.I.B 9869, when grown on either 3,5-xylenol or p-cresol, oxidized both m- and p-hydroxybenzyl alcohols. Two distinct NAD+-dependent m-hydroxybenzyl alcohol dehydrogenases were purified from cells grown on 3,5-xylenol. Each is active with a range of aromatic alcohols, including both m- and p-hydroxybenzyl alcohol, but differ in their relative rates with the various substrates. An NAD+-dependent alcohol dehydrogenase was also partially purified from p-cresol grown cells. This too was active with m- and p-hydroxybenzyl alcohol and other aromatic alcohols, but was not identical with either of the other two dehydrogenases. All three enzymes were unstable, but were stabilized by dithiothreitol and all were inhibited with p-chloromercuribenzoate. All were specific for NAD+ and each was shown to catalyse conversion of alcohol into aldehyde. PMID:743216

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

    SciTech Connect

    Clarkson, Sonya M.; Hamilton-Brehm, Scott D.; Giannone, Richard J.; Engle, Nancy L.; Tschaplinski, Timothy J.; Hettich, Robert L.; Elkins, James G.

    2014-12-03

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

  12. Catalytic and Molecular Properties of the Quinohemoprotein Tetrahydrofurfuryl Alcohol Dehydrogenase from Ralstonia eutropha Strain Bo

    PubMed Central

    Zarnt, Grit; Schräder, Thomas; Andreesen, Jan R.

    2001-01-01

    The quinohemoprotein tetrahydrofurfuryl alcohol dehydrogenase (THFA-DH) from Ralstonia eutropha strain Bo was investigated for its catalytic properties. The apparent kcat/Km and Ki values for several substrates were determined using ferricyanide as an artificial electron acceptor. The highest catalytic efficiency was obtained with n-pentanol exhibiting a kcat/Km value of 788 × 104 M−1 s−1. The enzyme showed substrate inhibition kinetics for most of the alcohols and aldehydes investigated. A stereoselective oxidation of chiral alcohols with a varying enantiomeric preference was observed. Initial rate studies using ethanol and acetaldehyde as substrates revealed that a ping-pong mechanism can be assumed for in vitro catalysis of THFA-DH. The gene encoding THFA-DH from R. eutropha strain Bo (tfaA) has been cloned and sequenced. The derived amino acid sequence showed an identity of up to 67% to the sequence of various quinoprotein and quinohemoprotein dehydrogenases. A comparison of the deduced sequence with the N-terminal amino acid sequence previously determined by Edman degradation analysis suggested the presence of a signal sequence of 27 residues. The primary structure of TfaA indicated that the protein has a tertiary structure quite similar to those of other quinoprotein dehydrogenases. PMID:11222593

  13. Cellobiose dehydrogenase in cellulose degradation

    SciTech Connect

    Eriksson, L.; Igarashi, Kiyohiko; Samejima, Masahiro

    1996-10-01

    Cellobiose dehydrogenase is produced by a variety of fungi. Although it was already discovered during the 70`s, it`s role in cellulose and lignin degradation is yet ambiguous. The enzyme contains both heme and FAD as prosthetic groups, and seems to have a domain specifically designed to bind the enzyme to cellulose. It`s affinity to amorphous cellulose is higher than to crystalline cellulose. We will report on the binding behavior of the enzyme, its usefulness in elucidation of cellulose structures and also, possibilities for applications such as its use in measuring individual and synergistic mechanisms for cellulose degradation by endo- and exo-glucanases.

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

    PubMed

    Pratihar, Sanjay

    2016-03-01

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

  15. Effects of aldehydes on the growth and lipid accumulation of oleaginous yeast Trichosporon fermentans.

    PubMed

    Huang, Chao; Wu, Hong; Liu, Qiu-ping; Li, Yuan-yuan; Zong, Min-hua

    2011-05-11

    The effects of five representative aldehydes in lignocellulosic hydrolysates on the growth and the lipid accumulation of oleaginous yeast Trichosporon fermentans were investigated for the first time. There was no relationship between the hydrophobicity and the toxicity of aldehyde, and 5-hydroxymethylfurfural was less toxic than aromatic aldehydes and furfural. Binary combination of aromatic aldehydes caused a synergistic inhibitory effect, but combination of furan and aromatic aldehydes reduced the inhibition instead. A longer lag phase was found due to the presence of aldehydes and the decrease of sugar consumption rate, but more xylose was utilized by T. fermentans in the presence of aldehydes, especially at their low concentrations. The variation of malic enzyme activity was not related to the delay of lipid accumulation. Furthermore, the inhibition of aldehydes on cell growth was more dependent on inoculum size, temperature, and initial pH than that on lipid content. PMID:21443267

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Direct N-acylation of lactams, oxazolidinones, and imidazolidinones with aldehydes by Shvo's catalyst.

    PubMed

    Zhang, Jian; Hong, Soon Hyeok

    2012-09-01

    Direct N-acylation of lactams, oxazolidinones, and imidazolidinones was achieved with aldehydes by Shvo's catalyst without using any other stoichiometric reagent. The N-acylations with α,β-unsaturated aldehydes were achieved with excellent yields. PMID:22913512

  18. An enzyme-amplified microtiter plate assay for ethanol: Its application to the detection of peanut ethanol and alcohol dehydrogenase

    SciTech Connect

    Chung, S.Y.; Vercellotti, J.R.; Sanders, T.H.

    1995-12-01

    A calorimetric microliter plate assay for ethanol amplified by aldehyde dehydrogenase (ALDH) was developed. In the assay ethanol from a sample took part in a chain-reaction catalyzed by alcohol dehydrogenase (ADH) and amplified by ALDH in the presence of NAD{sup +}, diaphorase, and p-ibdonitrotetrazolium-violet (INT-violet)(a precursor of red product). The resultant reaction gave a red color, the intensity of which was proportional to the amount of ethanol present. Using the technique, the content of activity from peanuts of differing maturity and curing stages were determined respectively. Data showed that immature peanuts had a higher level of ethanol and a lower ADH activity than mature peanuts, and that the level of ethanol and ADH activity decreased with the curing time. This indicates that peanut maturity and curing have an effect on ethanol. Also, this implies that other peanut volatiles could be affected in the same way as ethanol, a major volatile in peanuts.

  19. ANALYSIS OF ALDEHYDES AND KETONES IN THE GAS PHASE

    EPA Science Inventory

    The development and testing of a 2,4-dinitrophenylhydrazine-acetonitrile (DNPH-ACN) method for the analysis of aldehydes and ketones in ambient air are described. A discussion of interferences, preparation of calibration standards, analytical testing, fluorescence methods and car...

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

    PubMed

    Conklin, Daniel J

    2016-06-01

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

  1. A thermostable transketolase evolved for aliphatic aldehyde acceptors.

    PubMed

    Yi, Dong; Saravanan, Thangavelu; Devamani, Titu; Charmantray, Franck; Hecquet, Laurence; Fessner, Wolf-Dieter

    2015-01-11

    Directed evolution of the thermostable transketolase from Geobacillus stearothermophilus based on a pH-based colorimetric screening of smart libraries yielded several mutants with up to 16-fold higher activity for aliphatic aldehydes and high enantioselectivity (>95% ee) in the asymmetric carboligation step. PMID:25415647

  2. Interaction of aldehydes derived from lipid peroxidation and membrane proteins

    PubMed Central

    Pizzimenti, Stefania; Ciamporcero, Eric; Daga, Martina; Pettazzoni, Piergiorgio; Arcaro, Alessia; Cetrangolo, Gianpaolo; Minelli, Rosalba; Dianzani, Chiara; Lepore, Alessio; Gentile, Fabrizio; Barrera, Giuseppina

    2013-01-01

    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. PMID:24027536

  3. New preparation of diethyl methylformylphosphonate dimethylhydrazone: A reagent for aldehyde homologation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The phosphonate reagent, diethyl methylformyl-2-phosphonate dimethylhydrazone contains a protected aldehyde group instead of the usual ester group. It can be used for the two-carbon homologation of aldehydes to a, ß-unsaturated aldehydes. The reagent can be prepared in good overall yield (82%) and...

  4. Derivatization Strategy for the Comprehensive Characterization of Endogenous Fatty Aldehydes Using HPLC-Multiple Reaction Monitoring.

    PubMed

    Tie, Cai; Hu, Ting; Jia, Zhi-Xin; Zhang, Jin-Lan

    2016-08-01

    Fatty aldehydes are crucial substances that mediate a wide range of vital physiological functions, particularly lipid peroxidation. Fatty aldehydes such as acrolein and 4-hydroxynonenal (4-HNE) are considered potential biomarkers of myocardial ischemia and dementia, but analytical techniques for fatty aldehydes are lacking. In the present study, a comprehensive characterization strategy with high sensitivity and facility for fatty aldehydes based on derivatization and high-performance liquid chromatography-multiple reaction monitoring (HPLC-MRM) was developed. The fatty aldehydes of a biosample were derivatized using 2,4-bis(diethylamino)-6-hydrazino-1,3,5-triazine under mild and efficient reaction conditions at 37 °C for 15 min. The limit of detection (LOD) of the fatty aldehydes varied from 0.1 to 1 pg/mL, depending on the structures of these molecules. General MRM parameters were forged for the analysis of endogenous fatty aldehydes. "Heavy" derivatization reagents with 20 deuterium atoms were synthesized for both the discovery and comprehensive characterization of fatty aldehydes. More than 80 fatty aldehydes were detected in the biosamples. The new strategy was successfully implemented in global fatty aldehyde profiling of plasma and brain tissue of the bilateral common carotid artery (2VO) dementia rat model. Dozens of fatty aldehydes were significantly changed between the control and model groups. These findings further highlight the importance of endogenous fatty aldehydes. PMID:27397858

  5. Polysaccharide fraction from higher plants which strongly interacts with the cytosolic phosphorylase isozyme. I. Isolation and characterization. [Spinacia oleracea L. ; Pisum sativum L

    SciTech Connect

    Yang, Yi; Steup, M. )

    1990-11-01

    From leaves of Spinacia oleracea L. or from Pisum sativum L. and from cotyledons of germinating pea seeds a high molecular weight polysaccharide fraction was isolated. The apparent size of the fraction, as determined by gel filtration, was similar to that of dextran blue. Following acid hydrolysis the monomer content of the polysaccharide preparation was studied using high pressure liquid and thin layer chromatography. Glucose, galactose, arabinose, and ribose were the main monosaccharide compounds. The native polysaccharide preparation interacted strongly with the cytosolic isozyme of phosphorylase (EC 2.4.1.1). Interaction with the plastidic phosphorylase isozyme(s) was by far weaker. Interaction with the cytosolic isozyme was demonstrated by affinity electrophoresis, kinetic measurements, and by {sup 14}C-labeling experiments in which the glucosyl transfer from ({sup 14}C)glucose 1-phosphate to the polysaccharide preparation was monitored.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  7. The role of aldehyde/alcohol dehydrogenase (AdhE) in ethanol production from glycerol by Klebsiella pneumoniae.

    PubMed

    Oh, Baek-Rock; Hong, Won-Kyung; Heo, Sun-Yeon; Joe, Min-ho; Seo, Jeong-Woo; Kim, Chul Ho

    2013-02-01

    Transcriptome analysis of a K. pneumoniae GEM167 mutant strain derived by irradiation with gamma rays, which exhibited high-level production of ethanol from glycerol, showed that the mutant expressed AdhE at a high level. Ethanol production decreased significantly, from 8.8 to 0.5 g l(-1), when an adhE-deficient derivative of that strain was grown on glycerol. Bacterial growth was also reduced under such conditions, showing that AdhE plays a critical role in maintenance of redox balance by catalyzing ethanol production. Overexpression of AdhE enhanced ethanol production, from pure or crude glycerol, to a maximal level of 31.9 g l(-1) under fed-batch fermentation conditions; this is the highest level of ethanol production from glycerol reported to date. PMID:23296976

  8. A Novel Aldehyde Dehydrogenase-3 Activator (Alda-89) Protects Submandibular Gland Function from Irradiation without Accelerating Tumor Growth

    PubMed Central

    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

    2013-01-01

    Purpose To determine the effect of Alda-89 (an ALDH3 activitor) on (1) the function of irradiated (RT) submandibular gland (SMG) in mice, (2) its toxicity profile and (3) its effect on the growth of head and neck cancer (HNC) in vitro and in vivo. Experimental Design Adult mice were infused with Alda-89 or vehicle before, during and after RT. Saliva secretion was monitored weekly. Hematology, metabolic profile and post-mortem evaluation for toxicity were examined at the time of sacrifice. Alda-89 or vehicle was applied to HNC cell lines in vitro, and 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 HNC patients and correlated to freedom from relapse (FFR) and overall survival (OS). Results Alda-89 infusion significantly resulted in more whole saliva production and a higher percentage of preserved acini after RT compared to 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 to vehicle control, Alda-89 treatment did not accelerate HNC cell proliferation in vitro, nor did it affect tumor growth in vivo with or without RT. Higher expression of ALDH3A1 or ALDH3A2 was not significantly associated with worse FFR or OS in either HPV-positive or HPV-negative group. Conclusion Alda-89 preserves salivary function after RT without affecting HNC growth or causing measurable toxicity in mice. It is a promising candidate to mitigate RT-related xerostomia. PMID:23812668

  9. A PBPK MODEL FOR EVALUATING THE IMPACT OF ALDEHYDE DEHYDROGENASE POLYMORPHISMS ON COMPARATIVE RAT AND HUMAN NASAL TISSUE ACETALDEHYDE DOSIMETRY

    EPA Science Inventory

    ABSTRACT: Acetaldehyde is an important intermediate in chemical synthesis and a byproduct of normal oxidative metabolism of several industrially important compounds including ethanol, ethyl acetate and vinyl acetate. Chronic inhalation of acetaldehyde leads to degeneratio...

  10. A PBPK model for evaluating the impact of aldehyde dehydrogenase polymorphisms on comparative rat and human nasal tissue acetaldehyde dosimetry*

    EPA Science Inventory

    Acetaldehyde is an important intermediate in the chemical synthesis and normal oxidative metabolism of several industrially important compounds, including ethanol, ethyl acetate, and vinyl acetate. Chronic inhalation of acetaldehyde leads to degeneration of the olfactory and resp...

  11. Special Issue: Proceedings From the 9th International Congress on Isozymes, Genes, and Gene Families, San Antonio, TX, April 14-19, 1997

    SciTech Connect

    McCarrey, John R.; VandeBerg, John L.

    1998-10-01

    This volume includes 27 peer-reviewed papers, plus an overview of the International Congress on Genes, Gene Families, and Isozymes. These proceedings provide a representative portion of the outstanding scientific program compiled for the Congress. Presented is a volume that documents the vigorous state of this field, and the manner in which is has progressed to include a wide range of approaches, from classic isozyme analysis to modern molecular biology.

  12. Induction of a germination specific, low molecular weight, acid phosphatase isozyme with specific phosphotyrosine phosphatase activity in lentil (Lens esculenta) seeds.

    PubMed

    Bose, S K; Taneja, V

    1998-09-29

    A germination specific isozyme of acid phosphatase (EC 3.1.3.2) hydrolysing O-phospho-L-Tyrosine, pH optima 5.5 is induced in lentil seeds. When seeds at 0 h, 24 h and 36 h of germination are electrophorezed, native PAGE on specific enzyme staining shows several constitutive isozymes of acid phosphatases. At 48 h, an isozyme is induced which gradually decreases and then disappears at 108 h of germination. The short lived, induced isozyme is present in the embryo and seed-coat but not in the plumule and the radical. Induction of this isozyme is inhibited by cycloheximide and actinomycin-D and increased by plant growth regulators such as heteroauxin and gibbrellic acid treatment during germination. The induced isozyme is a single 30 kD polypeptide, with subunit molecular mass of 25 kD, shows activity for O-phospho-L-Tyrosine. It is strongly inhibited by vanadate (microM), molybdate, tungustate as also by iodoacetate, p-chloromercuribenzoate and diethylpyrocarbonate. This study shows for the first time that the germination induced low molecular weight Acid phosphatase is a Tyrosine phosphatase super family class IV enzyme, having a role in cellular differentiation and development during seed germination. PMID:9784397

  13. Single motoneuron succinate dehydrogenase activity.

    PubMed

    Chalmers, G R; Edgerton, V R

    1989-07-01

    We have developed a quantitative histochemical assay for measurement of succinate dehydrogenase (SDH) activity in single motoneurons. A computer image processing system was used to quantify the histochemical enzyme reaction product and to follow the time course of the reaction. The optimal concentration for each of the ingredients of the incubation medium for the SDH reaction was determined and the importance of using histochemical "blanks" in the determination of enzymatic activity was demonstrated. The enzymatic activity was linear with respect to reaction time and tissue thickness. The procedure described meets the criteria generally considered essential for establishment of a quantitative histochemical assay. The assay was then used to examine the SDH activity of cat and rat motoneurons. It was found that motoneurons with a small soma size had a wide range of SDH activity, whereas those with a large soma size were restricted to low SDH activity. PMID:2732457

  14. Glucose-6-Phosphate Dehydrogenase Deficiency.

    PubMed

    Luzzatto, Lucio; Nannelli, Caterina; Notaro, Rosario

    2016-04-01

    G6PD is a housekeeping gene expressed in all cells. Glucose-6-phosphate dehydrogenase (G6PD) is part of the pentose phosphate pathway, and its main physiologic role is to provide NADPH. G6PD deficiency, one of the commonest inherited enzyme abnormalities in humans, arises through one of many possible mutations, most of which reduce the stability of the enzyme and its level as red cells age. G6PD-deficient persons are mostly asymptomatic, but they can develop severe jaundice during the neonatal period and acute hemolytic anemia when they ingest fava beans or when they are exposed to certain infections or drugs. G6PD deficiency is a global health issue. PMID:27040960

  15. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C4 of the Plateau Pika (Ochotona curzoniae)

    PubMed Central

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2016-01-01

    Testis-specific lactate dehydrogenase (LDH-C4) is one of the lactate dehydrogenase (LDH) isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C4 in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae) belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000–5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C4 in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A4 (LDH-A4), Lactate Dehydrogenase B4 (LDH-B4), and LDH-C4 were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis (PAGE). The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km) of LDH-C4 for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C4 for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki) of the LDH isoenzymes varied: LDH-A4 (Ki = 26.900 mmol/L), LDH-B4 (Ki = 23.800 mmol/L), and LDH-C4 (Ki = 65.500 mmol/L). These data suggest that inhibition of lactate by LDH-A4 and LDH-B4 were stronger than LDH-C4. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C4. PMID:26751442

  16. Stomach Chitinase from Japanese Sardine Sardinops melanostictus: Purification, Characterization, and Molecular Cloning of Chitinase Isozymes with a Long Linker

    PubMed Central

    Kawashima, Satoshi; Ikehata, Hiroki; Tada, Chihiro; Ogino, Tomohiro; Kakizaki, Hiromi; Ikeda, Mana; Fukushima, Hideto; Matsumiya, Masahiro

    2016-01-01

    Fish express two different chitinases, acidic fish chitinase-1 (AFCase-1) and acidic fish chitinase-2 (AFCase-2), in the stomach. AFCase-1 and AFCase-2 have different degradation patterns, as fish efficiently degrade chitin ingested as food. For a comparison with the enzymatic properties and the primary structures of chitinase isozymes obtained previously from the stomach of demersal fish, in this study, we purified chitinase isozymes from the stomach of Japanese sardine Sardinops melanostictus, a surface fish that feeds on plankton, characterized the properties of these isozymes, and cloned the cDNAs encoding chitinases. We also predicted 3D structure models using the primary structures of S. melanostictus stomach chitinases. Two chitinase isozymes, SmeChiA (45 kDa) and SmeChiB (56 kDa), were purified from the stomach of S. melanostictus. Moreover, two cDNAs, SmeChi-1 encoding SmeChiA, and SmeChi-2 encoding SmeChiB were cloned. The linker regions of the deduced amino acid sequences of SmeChi-1 and SmeChi-2 (SmeChi-1 and SmeChi-2) are the longest among the fish stomach chitinases. In the cleavage pattern groups toward short substrates and the phylogenetic tree analysis, SmeChi-1 and SmeChi-2 were classified into AFCase-1 and AFCase-2, respectively. SmeChi-1 and SmeChi-2 had catalytic domains that consisted of a TIM-barrel (β/α)8–fold structure and a deep substrate-binding cleft. This is the first study showing the 3D structure models of fish stomach chitinases. PMID:26805857

  17. Discovery of Small Molecule Isozyme Non-specific Inhibitors of Mammalian Acetyl-CoA Carboxylase 1 and 2

    SciTech Connect

    Corbett, J.; Freeman-Cook, K; Elliott, R; Vajdos, F; Rajamohan, F; Kohls, D; Marr, E; Harwood Jr., H; Esler, W; et al.

    2010-01-01

    Screening Pfizer's compound library resulted in the identification of weak acetyl-CoA carboxylase inhibitors, from which were obtained rACC1 CT-domain co-crystal structures. Utilizing HTS hits and structure-based drug discovery, a more rigid inhibitor was designed and led to the discovery of sub-micromolar, spirochromanone non-specific ACC inhibitors. Low nanomolar, non-specific ACC-isozyme inhibitors that exhibited good rat pharmacokinetics were obtained from this chemotype.

  18. Tissue-specific expression of human arylsulfatase-C isozymes and steroid sulfatase.

    PubMed Central

    Munroe, D G; Chang, P L

    1987-01-01

    Steroid sulfatase (STS; E.C.3.1.6.2), which acts on 3-hydroxysteroid sulfates, and arylsulfatase-C (ARC; E.C.3.1.6.1), assayed with aromatic artificial substrates, are both membrane-bound, microsomal enzymes with alkaline pH optima. Although they copurify during preparation and their gene loci are mapped to the short arm of the human X chromosome where they appear to have escaped from X inactivation, it has not been settled whether STS and ARC are the same enzyme or not. Recent work from our laboratory has shown that ARC exists in two electrophoretically distinct forms in human fibroblasts. We now report that these two forms--the faster migrating (F) and more slowly migrating (S)--occur in human tissues. Each of 11 human tissue types from 10 subjects showed a consistent pattern of ARC isozymes. Thyroid, heart, spleen, skeletal muscle, and adrenal tissue mainly had the S form. In contrast, kidney, liver, and pancreas tissue had mainly the F form, while gonadal, lung, and intestinal tissue had both the S and the F forms. The question of escape of their gene locus from X-chromosome inactivation was examined by comparing the specific activities of ARC and STS in male-derived vis-à-vis female-derived tissues. The majority of the tissues did not show any significant difference in these activities between the sexes, the exceptions being heart muscle, gonadal, and kidney tissue. None showed the 1:2 ratio between male- and female-derived tissues expected of a locus that had escaped X inactivation. The question of identity between ARC and STS was examined by comparing the ratios of their activities in these tissue types: if the enzymes were identical, the ratios of their activities should have remained constant across the different tissue types. It was thus shown that ARC activity varied by as much as 100-fold, depending on the ARC isozymic pattern of the tissue. STS, measured as estrone sulfatase and dehydroepiandrosterone sulfatase, did not show similar variations. This

  19. INHIBITORY AND MECHANISTIC INVESTIGATIONS OF OXO-LIPIDS WITH HUMAN LIPOXYGENASE ISOZYMES

    PubMed Central

    Armstrong, Michelle M.; Diaz, Giovanni; Kenyon, Victor; Holman, Theodore R.

    2014-01-01

    Oxo-lipids, a large family of oxidized human lipoxygenase (hLOX) products, are of increasing interest to researchers due to their involvement in different inflammatory responses in the cell. Oxo-lipids are unique because they contain electrophilic sites that can potentially form covalent bonds through a Michael addition mechanism with nucleophilic residues in protein active sites and thus increase inhibitor potency. Due to the resemblance of oxo-lipids to LOX substrates, the inhibitor potency of 4 different oxo-lipids; 5-oxo-6,8,11,14-(E,Z,Z,Z)-eicosatetraenoic acid (5-oxo-ETE), 15-oxo-5,8,11,13-(Z,Z,Z,E)-eicosatetraenoic acid (15-oxo-ETE), 12-oxo-5,8,10,14-(Z,Z,E,Z)-eicosatetraenoic acid (12-oxo-ETE), and 13-oxo-9,11-(Z,E)-octadecadienoic acid (13-oxo-ODE) were determined against a library of LOX isozymes; leukocyte 5-lipoxygenase (h5-LOX), human reticulocyte 15-lipoxygenase-1 (h15-LOX-1), human platelet 12-lipoxygenase (h12-LOX), human epithelial 15-lipoxygenase-2 (h15-LOX-2), soybean 15-lipoxygenase-1 (s15-LOX-1), and rabbit reticulocyte 15-LOX (r15-LOX). 15-oxo-ETE exhibited the highest potency against h12-LOX, with an IC50 = 1 ± 0.1 μM and was highly selective. Steady state inhibition kinetic experiments determined 15-oxo-ETE to be a mixed inhibitor against h12-LOX, with a Kic value of 0.087 ± 0.008 μM and a Kiu value of 2.10 ± 0.8 μM. Time-dependent studies demonstrated irreversible inhibition with 12-oxo-ETE and h15-LOX-1, however, the concentration of 12-oxo-ETE required (Ki = 36.8 ± 13.2 μM) and the time frame (k2 = 0.0019 ± .00032 s−1) were not biologically relevant. These data are the first observations that oxo-lipids can inhibit LOX isozymes and may be another mechanism in which LOX products regulate LOX activity. PMID:24924423

  20. Changes of serum amylase, its isozyme fractions and amylase-creatinine clearance ratio in dogs with experimentally induced acute pancreatitis.

    PubMed

    Akuzawa, M; Morizono, M; Nagata, K; Hayano, S; Sakamoto, H; Yasuda, N; Okamoto, K; Kawasaki, Y; Deguchi, E

    1994-04-01

    To investigate the diagnostic application of amylase to canine pancreatic diseases, serum amylase activities, its isozyme fractions and amylase-creatinine clearance ratio (ACCR) were analyzed in normal intact dogs and dogs experimentally induced acute pancreatitis. There was no statistic difference between normal male and female dogs. Amylase specific activities in pancreatic tissue extracts were more than 2,300 times higher than that in serum, and were also higher than those in other tissues; parotid and mandibular salivary glands, lung, heart, liver, spleen, duodenum, jejunum, ileum and kidney. Following the chloroform injection into the pancreatic tissue, WBC increased from 6 to 240 hr and serum glucose significantly increased at 72 and 96 hr, and no urine glucose was detected. BUN as well as serum and urine creatinine showed normal levels. ACCR increased until 96 hr without statistic significance. Serum amylase activities increased significantly after 3 hr and its isozyme was separated into 4 fractions (Amy1-Amy4) in contrast to 3 fractions (Amy2-Amy4) in intact dogs. Since this extra Amy1 seen from 1 hr increasing after 6 hr similarly to other 3 fractions, the evaluation of serum amylase and its isozyme fractions was indicated to be useful for the diagnosis of acute pancreatitis in dogs. PMID:7521216

  1. Arabidopsis GERANYLGERANYL DIPHOSPHATE SYNTHASE 11 is a hub isozyme required for the production of most photosynthesis-related isoprenoids.

    PubMed

    Ruiz-Sola, M Águila; Coman, Diana; Beck, Gilles; Barja, M Victoria; Colinas, Maite; Graf, Alexander; Welsch, Ralf; Rütimann, Philipp; Bühlmann, Peter; Bigler, Laurent; Gruissem, Wilhelm; Rodríguez-Concepción, Manuel; Vranová, Eva

    2016-01-01

    Most plastid isoprenoids, including photosynthesis-related metabolites such as carotenoids and the side chain of chlorophylls, tocopherols (vitamin E), phylloquinones (vitamin K), and plastoquinones, derive from geranylgeranyl diphosphate (GGPP) synthesized by GGPP synthase (GGPPS) enzymes. Seven out of 10 functional GGPPS isozymes in Arabidopsis thaliana reside in plastids. We aimed to address the function of different GGPPS paralogues for plastid isoprenoid biosynthesis. We constructed a gene co-expression network (GCN) using GGPPS paralogues as guide genes and genes from the upstream and downstream pathways as query genes. Furthermore, knock-out and/or knock-down ggpps mutants were generated and their growth and metabolic phenotypes were analyzed. Also, interacting protein partners of GGPPS11 were searched for. Our data showed that GGPPS11, encoding the only plastid isozyme essential for plant development, functions as a hub gene among GGPPS paralogues and is required for the production of all major groups of plastid isoprenoids. Furthermore, we showed that the GGPPS11 protein physically interacts with enzymes that use GGPP for the production of carotenoids, chlorophylls, tocopherols, phylloquinone, and plastoquinone. GGPPS11 is a hub isozyme required for the production of most photosynthesis-related isoprenoids. Both gene co-expression and protein-protein interaction likely contribute to the channeling of GGPP by GGPPS11. PMID:26224411

  2. A possible role of NADPH-dependent cytochrome P450nor isozyme in glycolysis under denitrifying conditions.

    PubMed

    Watsuji, Tomo-o; Takaya, Naoki; Nakamura, Akira; Shoun, Hirofumi

    2003-05-01

    The denitrifying fungus Cylindrocarpon tonkinense contains two isozymes of cytochrome P450nor. One isozyme, P450nor1, uses NADH specifically as its electron donor whereas the other isozyme P450nor2 prefers NADPH to NADH. Here we show that P450nor1 is localized in both cytosol and mitochondria, like P450nor of Fusarium oxysporum, while P450nor2 is exclusively in cytosol. We also found that the addition of glucose as a carbon source to the culture media leads to the production of much more P450nor2 in the fungal cells than a non-fermentable substrate (glycerol or acetate) does. These results suggest that the NADP-dependent pentose phosphate cycle acts predominantly in C. tonkinense as the glycolysis pathway under the denitrifying conditions, which was confirmed by the observation that glucose induced enzyme activities involved in the cycle. These results showed that P450nor2 should act as the electron sink under anaerobic, denitrifying conditions to regenerate NADP+ for the pentose phosphate cycle. PMID:12834289

  3. Involvement of the "A" isozyme of methyltransferase II and the 29-kilodalton corrinoid protein in methanogenesis from monomethylamine.

    PubMed Central

    Burke, S A; Krzycki, J A

    1995-01-01

    An assay which allowed detection of proteins involved in the trimethylamine- or monomethylamine (MMA)-dependent methylation of coenzyme M (CoM) was developed. The two activities could be separated by anion-exchange chromatography. The unresolved activity responsible for MMA:CoM methyl transfer eluted from a gel permeation column in the molecular mass range of 32 kDa. The activity was purified to two monomeric proteins of 40 and 29 kDa. The preparation contained protein-bound corrinoid in a mixture of Co(II) and Co(III) states, as well as methyl-B12:CoM methyltransferase (MT2) activity. N-terminal sequence analysis demonstrated that the polypeptides were two previously identified proteins of undefined physiological function. The smaller polypeptide was the monomeric 29-kDa corrinoid protein. The larger polypeptide was the "A" isozyme of MT2. Individually purified preparations of both proteins increased the rate of MMA-dependent CoM methylation by approximately 1.7 mumol/min/mg of purified protein above background activity in the extract of methanol-grown cells. These results indicate that the 29-kDa corrinoid protein and the "A" isozyme of MT2 function in methanogenesis from MMA. A likely mechanism is that the 29-kDa corrinoid is methylated by MMA and the methyl group is then transferred by the "A" isozyme of MT2 to CoM. PMID:7635826

  4. Selective inhibition by chloramphenicol of pregnenolone-16. cap alpha. -carbonitrile-inducible rat liver cytochrome P-450 isozymes

    SciTech Connect

    Graves, P.E.; Kaminsky, L.S.; Halpert, J.

    1986-03-01

    Pregnenolone-16 ..cap alpha..-carbonitrile (PCN) has been shown to induce, in male rats, cytochrome P-450 isozymes responsible for the formation of R-10-hydroxywarfarin and R-dehydrowarfarin. Antibodies to the major PCN-inducible isozyme (PB/PCN-E) inhibit both activities in microsomal preparations. Recently the authors have shown that PCN treatment of female rats also induces the formation of both R-warfarin metabolites. However, in both sexes chloramphenicol (CAP) treatment selectively inhibits only the rate of formation of the R-dehydrowarfarin. A decrease in microsomal P-450 content occurs after in vivo administration of CAP to PCN-treated rats of both sexes. This is in contrast to the lack of effect of CAP on P-450 levels in phenobarbital-treated rats. Covalent binding of /sup 14/C-CAP to microsomal protein in vitro was increased 3 to 4-fold following PCN treatment. Chromatographic evidences suggests the presence of at least two PCN-induced isozymes of similar molecular weights in both male and female rat liver microsomes. These data are consistent with the multiplicity of PCN-inducible P-450 in rat liver.

  5. Chloroplasts and mitochondria have multiple heat tolerant isozymes of SOD and APX in leaf and inflorescence in Chenopodium album.

    PubMed

    Khanna-Chopra, Renu; Jajoo, Anjana; Semwal, Vimal Kumar

    2011-09-01

    Thermal stability of antioxidant defense enzymes superoxide dismutase (SOD, EC 1.15.1.1) and ascorbate peroxidase (APX, EC 1.11.1.11) was studied in chloroplasts and mitochondria of leaf and inflorescence in heat adaptive weed Chenopodium album. Leaf samples were taken in March (31°C/14°C) and young inflorescence (INF) was sampled at flowering in April (40°C/21°C). Leaf and INF chloroplast and mitochondrial fractions were subjected to elevated temperatures in vitro (5-100°C) for 30'. SOD and APX showed activity even after boiling treatment in both chloroplast and mitochondria of leaf and INF. SOD was more heat stable than APX in both chloroplasts and mitochondria in both the tissues. Chloroplast contained more heat stable SOD and APX isozymes than mitochondria in both leaf and INF. To the best of our knowledge this is the first report showing presence of thermostable APX isozymes (100°C for 30') in chloroplasts and mitochondria in C. album. Heat stable isozymes of SOD and APX in chloroplasts and mitochondria in leaves and inflorescence may contribute to heat tolerance in C. album. PMID:21763282

  6. Structure and function of phosphonoacetaldehyde dehydrogenase: the missing link in phosphonoacetate formation

    PubMed Central

    Agarwal, Vinayak; Peck, Spencer C.; Chen, Jui-Hui; Borisova, Svetlana A.; Chekan, Jonathan R.; van der Donk, Wilfred A.; Nair, Satish K.

    2015-01-01

    Summary Phosphonates (C-PO32−) have application as antibiotics, herbicides and detergents. In some environments, these molecules represent the predominant source for phosphorus, and several microbes have evolved dedicated enzymatic machineries for phosphonate degradation. For example, most common naturally occurring phosphonates can be catabolized to either phosphonoacetaldehyde or phosphonoacetate, which can then be hydrolyzed to generate inorganic phosphate and acetaldehyde or acetate, respectively. The phosphonoacetaldehyde oxidase gene (phnY) links these two hydrolytic processes and provides a previously unknown catabolic mechanism for phosphonoacetate production in the microbial metabolome. Here, we present biochemical characterization of PhnY and high-resolution crystal structures of the apo state, as well as complexes with substrate, cofactor and product. Kinetic analysis of active site mutants demonstrates how a highly conserved aldehyde dehydrogenase active site has been modified in nature to generate activity with a phosphonate substrate. PMID:24361046

  7. 11β-Hydroxysteroid Dehydrogenases: Intracellular Gate-Keepers of Tissue Glucocorticoid Action

    PubMed Central

    Chapman, Karen; Holmes, Megan

    2013-01-01

    Glucocorticoid action on target tissues is determined by the density of “nuclear” receptors and intracellular metabolism by the two isozymes of 11β-hydroxysteroid dehydrogenase (11β-HSD) which catalyze interconversion of active cortisol and corticosterone with inert cortisone and 11-dehydrocorticosterone. 11β-HSD type 1, a predominant reductase in most intact cells, catalyzes the regeneration of active glucocorticoids, thus amplifying cellular action. 11β-HSD1 is widely expressed in liver, adipose tissue, muscle, pancreatic islets, adult brain, inflammatory cells, and gonads. 11β-HSD1 is selectively elevated in adipose tissue in obesity where it contributes to metabolic complications. Similarly, 11β-HSD1 is elevated in the ageing brain where it exacerbates glucocorticoid-associated cognitive decline. Deficiency or selective inhibition of 11β-HSD1 improves multiple metabolic syndrome parameters in rodent models and human clinical trials and similarly improves cognitive function with ageing. The efficacy of inhibitors in human therapy remains unclear. 11β-HSD2 is a high-affinity dehydrogenase that inactivates glucocorticoids. In the distal nephron, 11β-HSD2 ensures that only aldosterone is an agonist at mineralocorticoid receptors (MR). 11β-HSD2 inhibition or genetic deficiency causes apparent mineralocorticoid excess and hypertension due to inappropriate glucocorticoid activation of renal MR. The placenta and fetus also highly express 11β-HSD2 which, by inactivating glucocorticoids, prevents premature maturation of fetal tissues and consequent developmental “programming.” The role of 11β-HSD2 as a marker of programming is being explored. The 11β-HSDs thus illuminate the emerging biology of intracrine control, afford important insights into human pathogenesis, and offer new tissue-restricted therapeutic avenues. PMID:23899562

  8. Aldehydes, carboxylic acids and inorganic nitrate during NSMCS

    NASA Astrophysics Data System (ADS)

    Grosjean, Daniel

    This article describes the methods and results of a study involving measurements of ambient levels of carboxylic acids (formic, acetic and oxalic), aldehydes (formaldehyde, acetaldehyde, propanal, n- butanal, n- pentanal and benzaldehyde) and total inorganic nitrate (nitric acid + particulate nitrate) during the Nitrogen Species Methods Comparison Study (NSMCS). Results for inorganic nitrate obtained using Teflon-nylon filter packs are compared to those obtained with nylon-nylon filter units and to those obtained by other methods during NSMCS. Calculations are presented of the distribution of gas phase nitrogen among NO, NO 2, HONO 2 and PAN, and of the positive bias due to PAN and HONO 2 in NOx measurements by chemiluminescence. Data for aldehydes and carboxylic acids are discussed in terms of sampling efficiency, gas-aerosol phase distribution, possible interferents (e.g. PAN as acetate on alkaline filters), diurnal variations, and relative importance of emissions vs in-situ daytime and night-time formation and removal processes.

  9. Nickel-Catalyzed Coupling of Alkenes, Aldehydes, and Silyl Triflates

    PubMed Central

    Ng, Sze-sze; Ho, Chun-Yu; Jamison, Timothy F.

    2011-01-01

    A full account of two recently developed nickel-catalyzed coupling reactions of alkenes, aldehydes and silyl triflates is presented. These reactions provide either allylic alcohol or homoallylic alcohol derivatives selectively, depending on the ligand employed. These processes are believed to be mechanistically distinct from Lewis acid-catalyzed carbonyl-ene reactions, and several lines of evidence supporting this hypothesis are discussed. PMID:16939275

  10. Ruthenium catalyzed hydrogenation of aldehyde with synthesis gas.

    PubMed

    Takahashi, Kohei; Nozaki, Kyoko

    2014-11-21

    The hydrogenation of aldehyde utilizing synthesis gas as a dihydrogen source was examined with various ruthenium catalysts, among which Ru-cyclopentadienone complexes (Shvo-type catalysts) exhibited higher activity than others. DFT calculations proved that the exchange of coordinated carbon monoxide by dihydrogen is relatively preferable in Shvo-type catalysts compared to others, which is a pre-equilibrium for the generation of the hydrogenation-active species. PMID:25372182

  11. Hydrogenation of Aldehydes Catalyzed by an Available Ruthenium Complex.

    PubMed

    Tan, Xuefeng; Wang, Guozhen; Zhu, Ziyue; Ren, Conghui; Zhou, Jinping; Lv, Hui; Zhang, Xiaoyong; Chung, Lung Wa; Zhang, Lina; Zhang, Xumu

    2016-04-01

    A readily available ruthenium(II) catalyst was developed for the catalytic hydrogenation of aldehydes with a TON (turnover number) up to 340000. It can be performed without base and solvent, showing highly industrial potential. High chemoselectivity can be achieved in the presence of alkenyl and ketone groups. Further application of this protocol in glucose reduction showed good efficiency. Theoretical studies revealed that the rate-determining step is the hydrogenation step, not the carboxylate-assisted H2 activation step. PMID:26974348

  12. A model system for QTL analysis: Effects of alcohol dehydrogenase genotype on alcohol pharmacokinetics

    SciTech Connect

    Martin, N.G.; Nightingale, B.; Whitfield, J.B.

    1994-09-01

    There is much interest in the detection of quantitative trait loci (QTL) - major genes which affect quantitative phenotypes. The relationship of polymorphism at known alcohol metabolizing enzyme loci to alcohol pharmacokinetics is a good model system. The three class I alcohol dehydrogenase genes are clustered on chromosome 4 and protein electrophoresis has revealed polymorphisms at the ADH2 and ADH3 loci. While different activities of the isozymes have been demonstrated in vitro, little work has been done in trying to relate ADH polymorphism to variation in ethanol metabolism in vivo. We previously measured ethanol metabolism and psychomotor reactivity in 206 twin pairs and demonstrated that most of the repeatable variation was genetic. We have now recontacted the twins to obtain DNA samples and used PCR with allele specific primers to type the ADH2 and ADH3 polymorphisms in 337 individual twins. FISHER has been used to estimate fixed effects of typed polymorphisms simultaneously with remaining linked and unlinked genetic variance. The ADH2*1-2 genotypes metabolize ethanol faster and attain a lower peak blood alcohol concentration than the more common ADH2*1-1 genotypes, although less than 3% of the variance is accounted for. There is no effect of ADH3 genotype. However, sib-pair linkage analysis suggests that there is a linked polymorphism which has a much greater effect on alcohol metabolism that those typed here.

  13. Epitopes of human testis-specific lactate dehydrogenase deduced from a cDNA sequence

    SciTech Connect

    Millan, J.L.; Driscoll, C.E.; LeVan, K.M.; Goldberg, E.

    1987-08-01

    The sequence and structure of human testis-specific L-lactate dehydrogenase (LDHC/sub 4/, LDHX; (L)-lactate:NAD/sup +/ oxidoreductase, EC 1.1.1.27) has been derived from analysis of a complementary DNA (cDNA) clone comprising the complete protein coding region of the enzyme. From the deduced amino acid sequence, human LDHC/sub 4/ is as different from rodent LDHC/sub 4/ (73% homology) as it is from human LDHA/sub 4/ (76% homology) and porcine LDHB/sub 4/ (68% homology). Subunit homologies are consistent with the conclusion that the LDHC gene arose by at least two independent duplication events. Furthermore, the lower degree of homology between mouse and human LDHC/sub 4/ and the appearance of this isozyme late in evolution suggests a higher rate of mutation in the mammalian LDHC genes than in the LDHA and -B genes. Comparison of exposed amino acid residues of discrete anti-genic determinants of mouse and human LDHC/sub 4/ reveals significant differences. Knowledge of the human LDHC/sub 4/ sequence will help design human-specific peptides useful in the development of a contraceptive vaccine.

  14. Glyceraldehyde-3-phosphate dehydrogenase gene from Zymomonas mobilis: cloning, sequencing, and identification of promoter region

    SciTech Connect

    Conway, T.; Sewell, G.W.; Ingram, L.O.

    1987-12-01

    The gene encoding glyceraldehyde-3-phosphate dehydrogenase was isolated from a library of Zymomonas mobilis DNA fragments by complementing a deficient strain of Escherichia coli. It contained tandem promoters which were recognized by E. coli but appeared to function less efficiently than the enteric lac promoter in E. coli. The open reading frame for this gene encoded 337 amino acids with an aggregate molecular weight of 36,099 (including the N-terminal methionine). The primary amino acid sequence for this gene had considerable functional homology and amino acid identity with other eukaryotic and bacterial genes. Based on this comparison, the gap gene from Z. mobilis appeared to be most closely related to that of the thermophilic bacteria and to the chloroplast isozymes. Comparison of this gene with other glycolytic enzymes from Z. mobilis revealed a conserved pattern of codon bias and several common features of gene structure. A tentative transcriptional consensus sequence is proposed for Z. mobilis based on comparison of the five known promoters for three glycolytic enzymes.

  15. Role of lactate dehydrogenase in metmyoglobin reduction and color stability of different bovine muscles.

    PubMed

    Kim, Y H; Keeton, J T; Smith, S B; Berghman, L R; Savell, J W

    2009-11-01

    The role of lactate dehydrogenase (LDH) in metmyoglobin reducing activity (MRA) and color stability of different bovine muscles was studied in two consecutive experiments. In experiment 1, three different bovine muscles -M. longissimus lumborum (LL), M. semimembranosus (SM), and M. psoas major (PM) - were obtained (n=7, respectively), cut into steaks, PVC packaged, and then displayed for 7days at 1°C. The LL was the most red over display time and had more (P<0.05) LDH-B activity (catalyzing toward NADH generation), LDH1 isoform expression, NADH, and higher (P<0.05) MRA than the other two muscles studied. The PM had the least color stability and lowest MRA. In experiment 2, LL steaks (n=8) were cut in half, one side syringe-injected with oxamate, and the other injected with distilled water. Inclusion of oxamate decreased (P<0.05) LDH-B activity, NADH, and a* values after 10days display at 1°C. These results suggest that variation in color stability of physiologically different muscles is regulated by different replenishment rates of NADH via different LDH isozymes. PMID:20416707

  16. Gene Expression Variation in Duplicate Lactate dehydrogenase Genes: Do Ecological Species Show Distinct Responses?

    PubMed Central

    Cristescu, Melania E.; Demiri, Bora; Altshuler, Ianina; Crease, Teresa J.

    2014-01-01

    Lactate dehydrogenase (LDH) has been shown to play an important role in adaptation of several aquatic species to different habitats. The genomes of Daphnia pulex, a pond species, and Daphnia pulicaria, a lake inhabitant, encode two L-LDH enzymes, LDHA and LDHB. We estimated relative levels of Ldh gene expression in these two closely related species and their hybrids in four environmental settings, each characterized by one of two temperatures (10°C or 20°C), and one of two concentrations of dissolved oxygen (DO; 6.5–7 mg/l or 2–3 mg/l). We found that levels of LdhA expression were 4 to 48 times higher than LdhB expression (p<0.005) in all three groups (the two parental species and hybrids). Moreover, levels of LdhB expression differed significantly (p<0.05) between D. pulex and D. pulicaria, but neither species differed from the hybrid. Consistently higher expression of LdhA relative to LdhB in both species and the hybrid suggests that the two isozymes could be performing different functions. No significant differences in levels of gene expression were observed among the four combinations of temperature and dissolved oxygen (p>0.1). Given that Daphnia dwell in environments characterized by fluctuating conditions with long periods of low dissolved oxygen concentration, we suggest that these species could employ regulated metabolic depression to survive in such environments. PMID:25080082

  17. Gene expression variation in duplicate lactate dehydrogenase genes: do ecological species show distinct responses?

    PubMed

    Cristescu, Melania E; Demiri, Bora; Altshuler, Ianina; Crease, Teresa J

    2014-01-01

    Lactate dehydrogenase (LDH) has been shown to play an important role in adaptation of several aquatic species to different habitats. The genomes of Daphnia pulex, a pond species, and Daphnia pulicaria, a lake inhabitant, encode two L-LDH enzymes, LDHA and LDHB. We estimated relative levels of Ldh gene expression in these two closely related species and their hybrids in four environmental settings, each characterized by one of two temperatures (10°C or 20°C), and one of two concentrations of dissolved oxygen (DO; 6.5-7 mg/l or 2-3 mg/l). We found that levels of LdhA expression were 4 to 48 times higher than LdhB expression (p<0.005) in all three groups (the two parental species and hybrids). Moreover, levels of LdhB expression differed significantly (p<0.05) between D. pulex and D. pulicaria, but neither species differed from the hybrid. Consistently higher expression of LdhA relative to LdhB in both species and the hybrid suggests that the two isozymes could be performing different functions. No significant differences in levels of gene expression were observed among the four combinations of temperature and dissolved oxygen (p>0.1). Given that Daphnia dwell in environments characterized by fluctuating conditions with long periods of low dissolved oxygen concentration, we suggest that these species could employ regulated metabolic depression to survive in such environments. PMID:25080082

  18. Structural and functional properties of glycerol-3-phosphate dehydrogenase from a mammalian hibernator.

    PubMed

    de la Roche, Marc; Tessier, Shannon N; Storey, Kenneth B

    2012-02-01

    Glycerol-3-phosphate dehydrogenase (G3PDH; E.C.1.1.1.8) was purified from liver and skeletal muscle of black-tailed prairie dogs (Cynomys ludivicianus), a hibernating species. Native and subunit molecular masses of the dimeric enzyme were 77 and 40 kD, respectively, and both tissues contained a single isozyme with a pI of 6.4. Kinetic parameters of purified G3PDH from prairie dog liver and muscle were characterized at 22 and 5 °C and compared with rabbit muscle G3PDH. Substrate affinities for hibernator muscle G3PDH were stable (NAD) or increased significantly (K(m) G3P and DHAP decreased) at low temperature whereas K(m) NAD and DHAP of rabbit G3PDH increased. Prairie dog G3PDH showed greater conservation of K(m) G3P over a wide temperature range as well as greater thermal stability and resistance to chemical denaturation by guanidine hydrochloride than the rabbit enzyme. In addition, using the protein sequence of the hibernating thirteen-lined ground squirrel (Ictidomys tridecemlineatus) and bioinformatics tools, the deduced protein structure of G3PDH was compared between heterothermic and homeothermic mammals. Structural and functional characteristics of G3PDH from the hibernating species would support enzyme function over a wide range of core body temperatures over cycles of torpor and arousal. PMID:22180227

  19. [Development of a new type soybean germplasm with null lipoxygenase isozymes].

    PubMed

    Han, Fen-Xia; Ding, An-Lin; Sun, Jun-Ming; Li, Gui-Ying

    2005-02-01

    Soybean protein is a kind of high-quality protein composed of balanced amino acids. It contains all kinds of amino acids, especially eight amino acids necessary for human, but also contains some components that are not good for human and affect food quality, such as Lipoxygenase (Lox) and Trypsin inhibitor (Ti). Nutritional value and processing quality of soybean can be improved by means of development of new variety with null Lox and Ti. In this paper, a new type soybean germplasm with null lipoxygenase isozymes was developed by Institute of Crop Sciences, Chinese Academy of Agricultural Sciences through years of biochemical marker assistant selection for null lipoxygenase by means of isoelectric focusing-polyacrylamid gel electrophoresis (IEF-PAGE) in the hybrid progenies of "96P17" (Female parent, a null lipoxygenase 2.3 line) and "93704" (Male parent, a null lipoxygenase 1.3 line). It is the first new soybean germplasm with null Lox1.2.3 genes in our country, which will contribute to soybean breeding for high quality, soybean production and utilization. In this paper, the development process of new type soybean germplasm is described. PMID:15759868

  20. Antibodies reacting to carbonic anhydrase isozymes (I and II) and albumin in sera from dogs.

    PubMed

    Nishita, Toshiho; Miyazaki, Rui; Miyazaki, Takae; Ochiai, Hideharu; Orito, Kensuke

    2016-06-01

    IgGs to carbonic anhydrase isozymes (CA-I and CA-II) and albumin were identified in dog serum. IgG titers were determined in the sera of asymptomatic dogs, and in dogs with atopic dermatitis, diarrhea and/or vomiting, diabetes and/or pancreatitis, kidney disease, hepatic disease, and thyroid gland disease, using ELISA. Low titres of IgG-reactive CA-I, CA-II, BSA, and CSA were found in the sera of healthy beagles. Compared with healthy beagles, there was a significant difference in the titers of antibodies against CA-I in asymptomatic dogs, dogs with diabetes and/or pancreatitis, or thyroid gland disease, or hepatic disease. Compared with healthy beagles, there was a significant difference in the antibody titer of anti-CA-II IgG in asymptomatic dogs and in those with hepatic disease. There was a significant difference in the antibody titer of anti-BSA IgG between healthy beagles and dogs with hepatic disease. PMID:27234558

  1. Selectivity of microbial acyl-CoA: cholesterol acyltransferase inhibitors toward isozymes.

    PubMed

    Ohshiro, Taichi; Rudel, Lawrence L; Omura, Satoshi; Tomoda, Hiroshi

    2007-01-01

    The selectivity of microbial inhibitors of acyl-CoA: cholesterol acyltransferase (ACAT) toward the two isozymes, ACAT1 and ACAT2, was assessed in cell-based assays. Purpactin A (IC50 values of ACAT1 vs. IC50 values of ACAT2; 2.5 microM vs. 1.5 microM), terpendole C (10 microM vs. 10 microM), glisoprenin A (4.3 microM vs. 10 microM), spylidone (25 microM vs. 5.0 microM) and synthetic CL-283,546 (0.1 microM vs. 0.09 microM) inhibited ACAT1 and ACAT2 to similar extents. Beauveriolides I (0.6 microM vs. 20 microM) and III (0.9 microM vs. >20 microM) inhibited ACAT1 rather selectively, while pyripyropenes A (>80 microM vs. 0.07 microM), B (48 microM vs. 2.0 microM), C (32 microM vs. 0.36 microM) and D (38 microM vs. 1.5 microM) showed selective inhibition against ACAT2. In particular, pyripyropene A was found to be the most selective ACAT2 inhibitor with a selective index of more than 1,000. PMID:17390588

  2. Simultaneous production of fatty acid methyl esters and diglycerides by four recombinant Candida rugosa lipase's isozymes.

    PubMed

    Chang, Shu-Wei; Huang, Myron; Hsieh, Yu-Hsun; Luo, Ying-Ting; Wu, Tsung-Ta; Tsai, Chia-Wen; Chen, Chin-Shuh; Shaw, Jei-Fu

    2014-07-15

    In this study, the catalytic efficiency of four recombinant CRL (Candida rugosa lipase) isozymes (LIP1-LIP4) towards the production of fatty acid methyl ester (FAME) was compared and evaluated as an alternative green method for industrial applications. The results indicated that the recombinant C. rugosa LIP1 enzyme exhibited the highest catalytic efficiency for FAME production compared to the recombinant C. rugosa LIP2-LIP4 enzymes. The optimal conditions were as follows: pH 7.0, methanol/soybean oil molar ratio: 3/1, enzyme amount: 2U (1.6 μL), reaction temperature: 20°C, 22 h of reaction time, and 3 times of methanol addition (1 mol/6h), and resulted in 61.5 ± 1.5 wt.% of FAME conversion. The reaction product contained also 10 wt.% of DAG with a ratio of 1,3-DAG to 1,2-DAG of approximately 4:6, and can be potentially used in industrial applications as a food emulsifier. PMID:24594166

  3. Cloning of human calcineurin A: Evidence for two isozymes and identification of a polyproline structural domain

    SciTech Connect

    Guerini, D.; Klee, C.B. )

    1989-12-01

    Two types (I and II) of cDNAs encoding the large (A) subunit of calcineurin, a calmodulin-regulated protein phosphatase, were isolated from human basal ganglia and brainstem mRNA. The complete sequences of the two calcineurin clones are identical except for a 54-base-pair insert in the type I clone and different 3{prime} ends including part of the coding sequence for the C termini of the two proteins. These findings suggest that calcineurin A consists of at least two isozymes that may result from alternative splicing events. The two forms of the enzyme differ in the C terminus, which contains an inhibitory domain rapidly severed by limited proteolysis. With the exception of an 18-amino acid insert, the central parts of the molecules, which harbor the catalytic domains, are identical and show extended similarities with the entire catalytic subunits of protein phosphatases 1 and 2A, defining a distinct family of protein phosphatases. The 40-residue N-terminal fragment, specific for calcineurin, contains a sequence of 11 successive prolines that is also found to bovine brain calcineurin by peptide sequencing. A role in the calmodulin activation of calcineurin is proposed for this novel structural element.

  4. Purification and properties of two isozymes of pyruvate kinase from Mucor racemosus.

    PubMed Central

    Hohn, T M; Paznokas, J L

    1987-01-01

    The dimorphic phycomycete Mucor racemosus was found to contain up to five electrophoretic forms of pyruvate kinase (ATP: pyruvate 2-O-phosphotransferase, EC 2.7.1.40) depending on growth conditions. M. racemosus hyphal cells grown on glutamic acid as the carbon source contained only the fastest electrophoretic form, designated PK1, while yeast cells grown on glucose contained only the slowest electrophoretic form, PK5. Intermediate electrophoretic forms PK2, PK3, and PK4 as well as PK1 and PK5 were found in hyphal cells grown on media containing fructose or cellibiose. All five electrophoretic forms had molecular weights of ca. 230,000 as determined from plots of log Rm versus acrylamide gel concentration. Both PK1 and PK5 were purified to homogeneity and determined to be homotetramers, with subunit molecular weights of 54,000 and 58,100, respectively. The amino acid content of PK1 and PK5 was determined and found to be similar but not identical. Analysis of limited tryptic digests and cyanogen bromide cleavage fragments of PK1 and PK5 indicate that the subunits of the two isozymes are significantly different. Images PMID:3611022

  5. Quantification of the electrophilic reactivities of aldehydes, imines, and enones.

    PubMed

    Appel, Roland; Mayr, Herbert

    2011-06-01

    The rates of the epoxidation reactions of aldehydes, of the aziridination reactions of aldimines, and of the cyclopropanation reactions of α,β-unsaturated ketones with aryl-stabilized dimethylsulfonium ylides have been determined photometrically in dimethyl sulfoxide (DMSO). All of these sulfur ylide-mediated cyclization reactions as well as the addition reactions of stabilized carbanions to N-tosyl-activated aldimines have been shown to follow a second-order rate law, where the rate constants reflect the (initial) CC bond formation between nucleophile and electrophile. The derived second-order rate constants (log k(2)) have been combined with the known nucleophilicity parameters (N, s(N)) of the aryl-stabilized sulfur ylides 4a,b and of the acceptor-substituted carbanions 4c-h to calculate the electrophilicity parameters E of aromatic and aliphatic aldehydes (1a-i), N-acceptor-substituted aromatic aldimines (2a-e), and α,β-unsaturated ketones (3a-f) according to the linear free-energy relationship log k(2) = s(N)(N + E) as defined in J. Am. Chem. Soc.2001, 123, 9500-9512. The data reported in this work provide the first quantitative comparison of the electrophilic reactivities of aldehydes, imines, and simple Michael acceptors in DMSO with carbocations and cationic metal-π complexes within our comprehensive electrophilicity scale. PMID:21553901

  6. The serotonin aldehyde, 5-HIAL, oligomerizes alpha-synuclein.

    PubMed

    Jinsmaa, Yunden; Cooney, Adele; Sullivan, Patricia; Sharabi, Yehonatan; Goldstein, David S

    2015-03-17

    In Parkinson's disease (PD) alpha-synuclein oligomers are thought to be pathogenic, and 3,4-dihydroxyphenylacetaldehyde (DOPAL), an obligate aldehyde intermediate in neuronal dopamine metabolism, potently oligomerizes alpha-synuclein. PD involves alpha-synuclein deposition in brainstem raphe nuclei; however, whether 5-hydroxyindoleacetaldehyde (5-HIAL), the aldehyde of serotonin, oligomerizes alpha-synuclein has been unknown. In this study we tested whether 5-HIAL oligomerizes alpha-synuclein in vitro and in PC12 cells conditionally over-expressing alpha-synuclein. Alpha-synuclein oligomers were quantified by western blotting after incubation of alpha-synuclein with serotonin and monoamine oxidase-A (MAO-A) to generate 5-HIAL or dopamine to generate DOPAL. Oligomerization of alpha-synuclein in PC12 cells over-expressing the protein was compared between vehicle-treated cells and cells incubated with levodopa to generate DOPAL or 5-hydroxytryptophan to generate 5-HIAL. Monoamine aldehyde mediation of the oligomerization was assessed using the MAO inhibitor, pargyline. Dopamine and serotonin incubated with MAO-A both strongly oligomerized alpha-synuclein (more than 10 times control); pargyline blocked the oligomerization. In synuclein overexpressing PC12 cells, levodopa and 5-hydroxytryptophan elicited pargyline-sensitive alpha-synuclein oligomerization. 5-HIAL oligomerizes alpha-synuclein both in vitro and in synuclein-overexpressing PC12 cells, in a manner similar to DOPAL. The findings may help explain loss of serotonergic neurons in PD. PMID:25637699

  7. The serotonin aldehyde, 5-HIAL, oligomerizes alpha-synuclein

    PubMed Central

    Jinsmaa, Yunden; Cooney, Adele; Sullivan, Patricia; Sharabi, Yehonatan; Goldstein, David S.

    2016-01-01

    In Parkinson’s disease (PD) alpha-synuclein oligomers are thought to be pathogenic, and 3,4-dihydroxyphenylacetaldehyde (DOPAL), an obligate aldehyde intermediate in neuronal dopamine metabolism, potently oligomerizes alpha-synuclein. PD involves alpha-synuclein deposition in brainstem raphe nuclei; however, whether 5-hydroxyindoleacetaldehyde (5-HIAL), the aldehyde of serotonin, oligomerizes alpha-synuclein has been unknown. In this study we tested whether 5-HIAL oligomerizes alpha-synuclein in vitro and in PC12 cells conditionally over-expressing alpha-synuclein. Alpha-synuclein oligomers were quantified by western blotting after incubation of alpha-synuclein with serotonin and monoamine oxidase-A (MAO-A) to generate 5-HIAL or dopamine to generate DOPAL. Oligomerization of alpha-synuclein in PC12 cells over-expressing the protein was compared between vehicle-treated cells and cells incubated with levodopa to generate DOPAL or 5-hydroxytryptophan to generate 5-HIAL. Monoamine aldehyde mediation of the oligomerization was assessed using the MAO inhibitor, pargyline. Dopamine and serotonin incubated with MAO-A both strongly oligomerized alpha-synuclein (more than 10 times control); pargyline blocked the oligomerization. In synuclein overexpressing PC12 cells, levodopa and 5-hydroxytryptophan elicited pargyline-sensitive alpha-synuclein oligomerization. 5-HIAL oligomerizes alpha-synuclein both in vitro and in synuclein-overexpressing PC12 cells, in a manner similar to DOPAL. The findings may help explain loss of serotonergic neurons in PD. PMID:25637699

  8. Volatile aldehydes in the mainstream smoke of the narghile waterpipe.

    PubMed

    Al Rashidi, M; Shihadeh, A; Saliba, N A

    2008-11-01

    Very little is known about the quality and quantity of toxicants yielded by the narghile, a subject of increasing importance as this method of tobacco smoking has become popular all over the world. This study is concerned with the identification and quantification of volatile aldehydes in the gas and particle phases of mainstream narghile smoke generated using a popular type of flavored ma'ssel tobacco mixture. These compounds were analyzed based on a modified version of the Environmental Protection Agency compendium method TO-11A. Using a standardized smoking machine protocol consisting of 171 puffs, 2.6s puff duration and 17s inter puff interval, the average yields of formaldehyde, acetaldehyde, acrolein, propionaldehyde and methacrolein were 630, 2520, 892, 403, and 106 microg/smoking session, respectively. The results showed that none of the aldehydes identified in this study are found in the particulate phase of the smoke, except for formaldehyde for which the partitioning coefficient was estimated as Kp = 3.3 x 10(-8) microg/m3. Given previously reported lung absorption fractions of circa 90% for volatile aldehydes, the yields measured in this study are sufficient to induce various diseases depending on the extent of exposure, and on the breathing patterns of the smokers. PMID:18834915

  9. γ-Unsaturated aldehydes as potential Lilial replacers.

    PubMed

    Schroeder, Martin; Mathys, Marion; Ehrensperger, Nadja; Büchel, Michelle

    2014-10-01

    A series of Claisen rearrangements was undertaken in order to find a replacement for Lilial (=3-(4-(tert-butyl)phenyl)-2-methylpropanal), a high-tonnage perfum