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Sample records for alcohol acetyl transferase

  1. Mimicking Insect Communication: Release and Detection of Pheromone, Biosynthesized by an Alcohol Acetyl Transferase Immobilized in a Microreactor

    PubMed Central

    Muñoz, Lourdes; Dimov, Nikolay; Carot-Sans, Gerard; Bula, Wojciech P.; Guerrero, Angel; Gardeniers, Han J. G. E.

    2012-01-01

    Infochemical production, release and detection of (Z,E)-9,11-tetradecadienyl acetate, the major component of the pheromone of the moth Spodoptera littoralis, is achieved in a novel microfluidic system designed to mimic the final step of the pheromone biosynthesis by immobilized recombinant alcohol acetyl transferase. The microfluidic system is part of an “artificial gland”, i.e., a chemoemitter that comprises a microreactor connected to a microevaporator and is able to produce and release a pre-defined amount of the major component of the pheromone from the corresponding (Z,E)-9,11-tetradecadienol. Performance of the entire chemoemitter has been assessed in electrophysiological and behavioral experiments. Electroantennographic depolarizations of the pheromone produced by the chemoemitter were ca. 40% relative to that evoked by the synthetic pheromone. In a wind tunnel, the pheromone released from the evaporator elicited on males a similar attraction behavior as 3 virgin females in most of the parameters considered. PMID:23155372

  2. The HTLV-1-encoded protein HBZ directly inhibits the acetyl transferase activity of p300/CBP

    PubMed Central

    Wurm, Torsten; Wright, Diana G.; Polakowski, Nicholas; Mesnard, Jean-Michel; Lemasson, Isabelle

    2012-01-01

    The homologous cellular coactivators p300 and CBP contain intrinsic lysine acetyl transferase (termed HAT) activity. This activity is responsible for acetylation of several sites on the histones as well as modification of transcription factors. In a previous study, we found that HBZ, encoded by the Human T-cell Leukemia Virus type 1 (HTLV-1), binds to multiple domains of p300/CBP, including the HAT domain. In this study, we found that HBZ inhibits the HAT activity of p300/CBP through the bZIP domain of the viral protein. This effect correlated with a reduction of H3K18 acetylation, a specific target of p300/CBP, in cells expressing HBZ. Interestingly, lower levels of H3K18 acetylation were detected in HTLV-1 infected cells compared to non-infected cells. The inhibitory effect of HBZ was not limited to histones, as HBZ also inhibited acetylation of the NF-κB subunit, p65, and the tumor suppressor, p53. Recent studies reported that mutations in the HAT domain of p300/CBP that cause a defect in acetylation are found in certain types of leukemia. These observations suggest that inhibition of the HAT activity by HBZ is important for the development of adult T-cell leukemia associated with HTLV-1 infection. PMID:22434882

  3. Riboswitch control of induction of aminoglycoside resistance acetyl and adenyl-transferases

    PubMed Central

    He, Weizhi; Zhang, Xuhui; Zhang, Jun; Jia, Xu; Zhang, Jing; Sun, Wenxia; Jiang, Hengyi; Chen, Dongrong; Murchie, Alastair IH

    2013-01-01

    The acquisition of antibiotic resistance by human pathogens poses a significant threat to public health. The mechanisms that control the proliferation and expression of antibiotic resistance genes are not yet completely understood. The aminoglycosides are a historically important class of antibiotics that were introduced in the 1940s. Aminoglycoside resistance is conferred most commonly through enzymatic modification of the drug or enzymatic modification of the target rRNA through methylation or through the overexpression of efflux pumps. In our recent paper, we reported that expression of the aminoglycoside resistance genes encoding the aminoglycoside acetyl transferase (AAC) and aminoglycoside adenyl transferase (AAD) enzymes was controlled by an aminoglycoside-sensing riboswitch RNA. This riboswitch is embedded in the leader RNA of the aac/aad genes and is associated with the integron cassette system. The leader RNA can sense and bind specific aminoglycosides such that the binding causes a structural transition in the leader RNA, which leads to the induction of aminoglycoside antibiotic resistance. Specific aminoglycosides induce reporter gene expression mediated by the leader RNA. Aminoglycoside RNA binding was measured directly and, aminoglycoside-induced changes in RNA structure monitored by chemical probing. UV cross-linking and mutational analysis identified potential aminoglycoside binding sites on the RNA. PMID:23880830

  4. Role of Carnitine Acetyl Transferase in Regulation of Nitric Oxide Signaling in Pulmonary Arterial Endothelial Cells

    PubMed Central

    Sharma, Shruti; Sun, Xutong; Agarwal, Saurabh; Rafikov, Ruslan; Dasarathy, Sridevi; Kumar, Sanjiv; Black, Stephen M.

    2013-01-01

    Congenital heart defects with increased pulmonary blood flow (PBF) result in pulmonary endothelial dysfunction that is dependent, at least in part, on decreases in nitric oxide (NO) signaling. Utilizing a lamb model with left-to-right shunting of blood and increased PBF that mimics the human disease, we have recently shown that a disruption in carnitine homeostasis, due to a decreased carnitine acetyl transferase (CrAT) activity, correlates with decreased bioavailable NO. Thus, we undertook this study to test the hypothesis that the CrAT enzyme plays a major role in regulating NO signaling through its effect on mitochondrial function. We utilized the siRNA gene knockdown approach to mimic the effect of decreased CrAT activity in pulmonary arterial endothelial cells (PAEC). Our data indicate that silencing the CrAT gene disrupted cellular carnitine homeostasis, reduced the expression of mitochondrial superoxide dismutase-and resulted in an increase in oxidative stress within the mitochondrion. CrAT gene silencing also disrupted mitochondrial bioenergetics resulting in reduced ATP generation and decreased NO signaling secondary to a reduction in eNOS/Hsp90 interactions. Thus, this study links the disruption of carnitine homeostasis to the loss of NO signaling observed in children with CHD. Preserving carnitine homeostasis may have important clinical implications that warrant further investigation. PMID:23344032

  5. Glutathione S-transferase class mu in French alcoholic cirrhotic patients.

    PubMed

    Groppi, A; Coutelle, C; Fleury, B; Iron, A; Begueret, J; Couzigou, P

    1991-09-01

    The lack of glutathione S-transferase mu (GST mu) was examined in 45 healthy French Caucasians and 45 alcoholic cirrhotic French Caucasians: microsamples of blood were taken and DNA amplified by the polymerase chain reaction. We have concluded that there is no relationship between this genotype and the development of alcoholic cirrhosis in these heavy consumers of ethanol.

  6. Behavioral Neuroadaptation to Alcohol: From Glucocorticoids to Histone Acetylation

    PubMed Central

    Mons, Nicole; Beracochea, Daniel

    2016-01-01

    neuroadaptive changes during withdrawal from chronic alcohol intake. It then highlights the role of cAMP–PKA–CREB signaling cascade and histone acetylation within the PFC and limbic structures in alcohol-induced anxiety and behavioral impairments, and how an understanding of functional alterations of these pathways might lead to better treatments for neuropsychiatric disorders. PMID:27766083

  7. Alcohol-Induced Histone Acetylation Reveals a Gene Network Involved in Alcohol Tolerance

    PubMed Central

    Ghezzi, Alfredo; Krishnan, Harish R.; Lew, Linda; Prado, Francisco J.; Ong, Darryl S.; Atkinson, Nigel S.

    2013-01-01

    Sustained or repeated exposure to sedating drugs, such as alcohol, triggers homeostatic adaptations in the brain that lead to the development of drug tolerance and dependence. These adaptations involve long-term changes in the transcription of drug-responsive genes as well as an epigenetic restructuring of chromosomal regions that is thought to signal and maintain the altered transcriptional state. Alcohol-induced epigenetic changes have been shown to be important in the long-term adaptation that leads to alcohol tolerance and dependence endophenotypes. A major constraint impeding progress is that alcohol produces a surfeit of changes in gene expression, most of which may not make any meaningful contribution to the ethanol response under study. Here we used a novel genomic epigenetic approach to find genes relevant for functional alcohol tolerance by exploiting the commonalities of two chemically distinct alcohols. In Drosophila melanogaster, ethanol and benzyl alcohol induce mutual cross-tolerance, indicating that they share a common mechanism for producing tolerance. We surveyed the genome-wide changes in histone acetylation that occur in response to these drugs. Each drug induces modifications in a large number of genes. The genes that respond similarly to either treatment, however, represent a subgroup enriched for genes important for the common tolerance response. Genes were functionally tested for behavioral tolerance to the sedative effects of ethanol and benzyl alcohol using mutant and inducible RNAi stocks. We identified a network of genes that are essential for the development of tolerance to sedation by alcohol. PMID:24348266

  8. Molecular basis for the autoregulation of the protein acetyl transferase Rtt109

    PubMed Central

    Stavropoulos, Pete; Nagy, Vivien; Blobel, Günter; Hoelz, André

    2008-01-01

    Rtt109 is a protein acetyltransferase (PAT) that is responsible for the acetylation of lysine-56 of histone 3 (H3K56) in yeast. H3K56 acetylation has been implicated in the weakening of the interaction between the histone core and the surrounding DNA in the nucleosomal particle. Rtt109, in cooperation with various histone chaperones, promotes genomic stability and is required for resistance to DNA damaging agents. Here, we present the crystal structure of Rtt109 in complex with acetyl-CoA at a 2.0-Å resolution. Rtt109 consists of a core PAT domain, which binds the acetyl-CoA cofactor. A second domain, the activation domain, is tightly associated with the PAT domain. Autoacetylation of lysine-290 within the activation domain is required for stabilizing the interaction between the two domains and is essential for catalysis. Biochemical analysis demonstrates the requirement of a loop within the PAT domain for the binding of the histone chaperone Vps75, and mutational analysis identifies key residues for catalysis. We propose a model in which the autoacetylation of Rtt109 is crucial for the regulation of its catalytic activity. PMID:18719104

  9. Histone Acetyl Transferase (HAT) HBO1 and JADE1 in Epithelial Cell Regeneration

    PubMed Central

    Havasi, Andrea; Haegele, Joseph A.; Gall, Jonathan M.; Blackmon, Sherry; Ichimura, Takaharu; Bonegio, Ramon G.; Panchenko, Maria V.

    2014-01-01

    HBO1 acetylates lysine residues of histones and is involved in DNA replication and gene transcription. Two isoforms of JADE1, JADE1S and JADE1L, bind HBO1 and promote acetylation of histones in chromatin context. We characterized the role of JADE1-HBO1 complexes in vitro and in vivo during epithelial cell replication. Down-regulation of JADE1 by siRNA diminished the rate of DNA synthesis in cultured cells, decreased endogenous HBO1 protein expression, and prevented chromatin recruitment of replication factor Mcm7, demonstrating that JADE1 is required for cell proliferation. We used a murine model of acute kidney injury to examine expression of HBO1-JADE1S/L in injured and regenerating epithelial tissue. In control kidneys, JADE1S, JADE1L, and HBO1 were expressed in nuclei of proximal and distal tubular epithelial cells. Ischemia and reperfusion injury resulted in an initial decrease in JADE1S, JADE1L, and HBO1 protein levels, which returned to baseline during renal recovery. HBO1 and JADE1S recovered as cell proliferation reached its maximum, whereas JADE1L recovered after bulk proliferation had ceased. The temporal expression of JADE1S correlated with the acetylation of histone H4 on lysines 5 and 12, but not with acetylation of histone H3 on lysine 14, demonstrating that the JADE1S-HBO1 complex specifically marks H4 during epithelial cell proliferation. These data implicate JADE1-HBO1 complex in acute kidney injury and suggest distinct roles for JADE1 isoforms during epithelial cell recovery. PMID:23159946

  10. Glutathione-S-transferase GST M1 "null" genotype and the risk of alcoholic liver disease.

    PubMed

    Savolainen, V T; Pjarinen, J; Perola, M; Penttilä, A; Karhunen, P J

    1996-11-01

    The present study was conducted to investigate possible association between the occurrence of glutathione-S-transferase GST M1 "null" genotype and alcoholic liver disease (ALD). The"null" genotype indicating absent activity of class mu glutathione transferase was assessed in 33 abstainers, 43 moderate alcohol consumers, and 313 heavy alcohol consumers by polymerase chain reaction. The genotypes were compared with occurrence of alcoholic fatty liver, alcoholic hepatitis, and alcoholic liver fibrosis. The "null" genotype was found among 44.7% of patients in the series, with no significant differences between different consumption groups: controls, 36.4%; moderate consumers, 39.5%; and heavy consumers, 46.3%. Occurrence of GST M1 "null" genotype was not associated with occurrence ALD among moderate alcohol consumers. Frequency of the "null" genotype was, however, statistically nearly significantly [p = 0.07, odds ratio (OR) = 1.75] lower among heavy consumers with normal liver histology than in alcoholics with ALD. Furthermore, when compared with heavy consumers without ALD, the "null" genotype was nearly significantly more frequent among heavy consumers with at least slight liver fibrosis (p = 0.05, OR = 1.8) and statistically significantly more frequent among among alcoholics with advanced liver fibrosis (p < 0.025, OR = 2.3). Results of the present Finnish association study suggest that homozygous deletion of the GST M1 gene may indicate increased susceptibility to develop irreversible liver damage in response to the toxic effects of ethanol. Significant association was found between the occurrence of the "null" genotype and the occurrence of alcoholic liver cirrhosis.

  11. The two paralogue phoN (phosphinothricin acetyl transferase) genes of Pseudomonas putida encode functionally different proteins.

    PubMed

    Páez-Espino, A David; Chavarría, Max; de Lorenzo, Víctor

    2015-09-01

    Phosphinothricin (PPT) is a non-specific inhibitor of glutamine synthetase that has been employed as herbicide for selection of transgenic plants expressing cognate resistance genes. While the soil bacterium Pseudomonas putida KT2440 has been generally considered PPT-sensitive, inspection of its genome sequence reveals the presence of two highly similar open reading frames (PP_1924 and PP_4846) encoding acetylases with a potential to cause tolerance to the herbicide. To explore this possibility, each of these genes (named phoN1 and phoN2) was separately cloned and their activities examined in vivo and in vitro. Genetic and biochemical evidence indicated that phoN1 encodes a bona fide PPT-acetyl transferase, the expression of which suffices to make P. putida tolerant to high concentrations of the herbicide. In contrast, PhoN2 does not act on PPT but displays instead activity against methionine sulfoximine (MetSox), another glutamine synthetase inhibitor. When the geometry of the substrate-binding site of PhoN1 was grafted with the equivalent residues of the predicted PhoN2 structure, the resulting protein increased significantly MetSox resistance of the expression host concomitantly with the loss of activity on PPT. These observations uncover intricate biochemical and genetic interactions among soil microorganisms and how they can be perturbed by exposure to generic herbicides in soil. PMID:25684119

  12. Thiopurine metabolites variations during co-treatment with aminosalicylates for inflammatory bowel disease: Effect of N-acetyl transferase polymorphisms

    PubMed Central

    Stocco, Gabriele; Cuzzoni, Eva; De Iudicibus, Sara; Favretto, Diego; Malusà, Noelia; Martelossi, Stefano; Pozzi, Elena; Lionetti, Paolo; Ventura, Alessandro; Decorti, Giuliana

    2015-01-01

    AIM: To evaluate variation of the concentration of thiopurine metabolites after 5-aminosalicylate (5-ASA) interruption and the role of genetic polymorphisms of N-acetyl transferase (NAT) 1 and 2. METHODS: Concentrations of thioguanine nucleotides (TGN) and methymercaptopurine nucleotides (MMPN), metabolites of thiopurines, were measured by high performance liquid chromatography in 12 young patients (3 females and 9 males, median age 16 years) with inflammatory bowel disease (6 Crohn’s disease and 6 ulcerative colitis) treated with thiopurines (7 mercaptopurine and 5 azathioprine) and 5-ASA. Blood samples were collected one month before and one month after the interruption of 5-ASA. DNA was extracted and genotyping of NAT1, NAT2, inosine triphosphate pyrophosphatase (ITPA) and thiopurine methyl transferase (TPMT) genes was performed using PCR assays. RESULTS: Median TGN concentration before 5-ASA interruption was 270 pmol/8 x 108 erythrocytes (range: 145-750); after the interruption of the aminosalicylate, a 35% reduction in TGN mean concentrations (absolute mean reduction 109 pmol/8 × 108 erythrocytes) was observed (median 221 pmol/8 × 108 erythrocytes, range: 96-427, P value linear mixed effects model 0.0011). Demographic and clinical covariates were not related to thiopurine metabolites concentrations. All patients were wild-type for the most relevant ITPA and TPMT variants. For NAT1 genotyping, 7 subjects presented an allele combination corresponding to fast enzymatic activity and 5 to slow activity. NAT1 genotypes corresponding to fast enzymatic activity were associated with reduced TGN concentration (P value linear mixed effects model 0.033), putatively because of increased 5-ASA inactivation and consequent reduced inhibition of thiopurine metabolism. The effect of NAT1 status on TGN seems to be persistent even after one month since the interruption of the aminosalicylate. No effect of NAT1 genotypes was shown on MMPN concentrations. NAT2 genotyping

  13. N-Heterocyclic Carbene-Catalyzed Alcohol Acetylation: An Organic Experiment Using Organocatalysis

    ERIC Educational Resources Information Center

    Morgan, John P.; Shrimp, Jonathan H.

    2014-01-01

    Undergraduate students in the teaching laboratory have successfully used N-heterocyclic carbenes (NHCs) as organocatalysts for the acetylation of primary alcohols, despite the high water sensitivity of uncomplexed ("free") NHCs. The free NHC readily reacted with chloroform, resulting in an air- and moisture-stable adduct that liberates…

  14. Arylamine N-acetyl Transferase (NAT) in the blue secretion of Telescopium telescopium: xenobiotic metabolizing enzyme as a biomarker for detection of environmental pollution.

    PubMed

    Gorain, Bapi; Chakraborty, Sumon; Pal, Murari Mohan; Sarkar, Ratul; Samanta, Samir Kumar; Karmakar, Sanmoy; Sen, Tuhinadri

    2014-01-01

    Telescopium telescopium, a marine mollusc collected from Sundarban mangrove, belongs to the largest mollusca phylum in the world and exudes a blue secretion when stimulated mechanically. The blue secretion was found to metabolize (preferentially) para-amino benzoic acid, a substrate for N-acetyl transferase (NAT), thereby indicating acetyl transferase like activity of the secretion. Attempts were also made to characterise bioactive fraction of the blue secretion and to further use this as a biomarker for monitoring of marine pollution. NAT like enzyme from marine mollusc is a potential candidate for detoxification of different harmful chemicals. A partially purified extract of blue secretion was obtained by fractional precipitation with (NH4)2SO4. From different fractions obtained by precipitation, the 0-30% fraction (30S) displayed NAT like activity (using para amino benzoic acid as a substrate with para nitrophenyl phosphate or acetyl coenzyme A as acetyl group donors). Maximum NAT like enzyme activity was attained at 25°C and at a pH of 6. The enzyme activity was found to be inhibited by 5 mM phenyl methyl sulfonyl fluoride. The divalent metal ions reduced NAT like activity of 30S. Moreover, Cu(2+) and Zn(2+) (at concentration of 1 mM) completely inhibited NAT activity. The thermal stability and bench-top stability studies were performed and it was found that the enzyme was stable at room temperature for more than 24 hours. Results from the present study further indicate that heavy metal content in blue secretion gradually decreased from pre-monsoon to post-monsoon season, which also corresponded to the change in NAT like activity. Therefore, this article stresses the importance of biomarker research for monitoring pollution.

  15. Arylamine N-acetyl Transferase (NAT) in the blue secretion of Telescopium telescopium: xenobiotic metabolizing enzyme as a biomarker for detection of environmental pollution.

    PubMed

    Gorain, Bapi; Chakraborty, Sumon; Pal, Murari Mohan; Sarkar, Ratul; Samanta, Samir Kumar; Karmakar, Sanmoy; Sen, Tuhinadri

    2014-01-01

    Telescopium telescopium, a marine mollusc collected from Sundarban mangrove, belongs to the largest mollusca phylum in the world and exudes a blue secretion when stimulated mechanically. The blue secretion was found to metabolize (preferentially) para-amino benzoic acid, a substrate for N-acetyl transferase (NAT), thereby indicating acetyl transferase like activity of the secretion. Attempts were also made to characterise bioactive fraction of the blue secretion and to further use this as a biomarker for monitoring of marine pollution. NAT like enzyme from marine mollusc is a potential candidate for detoxification of different harmful chemicals. A partially purified extract of blue secretion was obtained by fractional precipitation with (NH4)2SO4. From different fractions obtained by precipitation, the 0-30% fraction (30S) displayed NAT like activity (using para amino benzoic acid as a substrate with para nitrophenyl phosphate or acetyl coenzyme A as acetyl group donors). Maximum NAT like enzyme activity was attained at 25°C and at a pH of 6. The enzyme activity was found to be inhibited by 5 mM phenyl methyl sulfonyl fluoride. The divalent metal ions reduced NAT like activity of 30S. Moreover, Cu(2+) and Zn(2+) (at concentration of 1 mM) completely inhibited NAT activity. The thermal stability and bench-top stability studies were performed and it was found that the enzyme was stable at room temperature for more than 24 hours. Results from the present study further indicate that heavy metal content in blue secretion gradually decreased from pre-monsoon to post-monsoon season, which also corresponded to the change in NAT like activity. Therefore, this article stresses the importance of biomarker research for monitoring pollution. PMID:26034680

  16. Rhizobial NodL O-Acetyl Transferase and NodS N-Methyl Transferase Functionally Interfere in Production of Modified Nod Factors

    PubMed Central

    López-Lara, Isabel M.; Kafetzopoulos, Dimitris; Spaink, Herman P.; Thomas-Oates, Jane E.

    2001-01-01

    The products of the rhizobial nodulation genes are involved in the biosynthesis of lipochitin oligosaccharides (LCOs), which are host-specific signal molecules required for nodule formation. The presence of an O-acetyl group on C-6 of the nonreducing N-acetylglucosamine residue of LCOs is due to the enzymatic activity of NodL. Here we show that transfer of the nodL gene into four rhizobial species that all normally produce LCOs that are not modified on C-6 of the nonreducing terminal residue results in production of LCOs, the majority of which have an acetyl residue substituted on C-6. Surprisingly, in transconjugant strains of Mesorhizobium loti, Rhizobium etli, and Rhizobium tropici carrying nodL, such acetylation of LCOs prevents the endogenous nodS-dependent transfer of the N-methyl group that is found as a substituent of the acylated nitrogen atom. To study this interference between nodL and nodS, we have cloned the nodS gene of M. loti and used its product in in vitro experiments in combination with purified NodL protein. It has previously been shown that a chitooligosaccharide N deacetylated on the nonreducing terminus (the so-called NodBC metabolite) is the preferred substrate for NodS as well as for NodL. Here we show that the NodBC metabolite, acetylated by NodL, is not used by the NodS protein as a substrate while the NodL protein can acetylate the NodBC metabolite that has been methylated by NodS. PMID:11344149

  17. Crystal Structure of TDP-Fucosamine Acetyl Transferase (WECD) from Escherichia Coli, an Enzyme Required for Enterobacterial Common Antigen Synthesis

    SciTech Connect

    Hung,M.; Rangarajan, E.; Munger, C.; Nadeau, G.; Sulea, T.; Matte, A.

    2006-01-01

    Enterobacterial common antigen (ECA) is a polysaccharide found on the outer membrane of virtually all gram-negative enteric bacteria and consists of three sugars, N-acetyl-D-glucosamine, N-acetyl-D-mannosaminuronic acid, and 4-acetamido-4,6-dideoxy-D-galactose, organized into trisaccharide repeating units having the sequence {yields}(3)-{alpha}-D-Fuc4NAc-(1{yields}4)-{beta}-D-ManNAcA-(1{yields}4)-{alpha}-D-GlcNAc-(1{yields}). While the precise function of ECA is unknown, it has been linked to the resistance of Shiga-toxin-producing Escherichia coli (STEC) O157:H7 to organic acids and the resistance of Salmonella enterica to bile salts. The final step in the synthesis of 4-acetamido-4,6-dideoxy-D-galactose, the acetyl-coenzyme A (CoA)-dependent acetylation of the 4-amino group, is carried out by TDP-fucosamine acetyltransferase (WecD). We have determined the crystal structure of WecD in apo form at a 1.95-Angstroms resolution and bound to acetyl-CoA at a 1.66-Angstroms resolution. WecD is a dimeric enzyme, with each monomer adopting the GNAT N-acetyltransferase fold, common to a number of enzymes involved in acetylation of histones, aminoglycoside antibiotics, serotonin, and sugars. The crystal structure of WecD, however, represents the first structure of a GNAT family member that acts on nucleotide sugars. Based on this cocrystal structure, we have used flexible docking to generate a WecD-bound model of the acetyl-CoA-TDP-fucosamine tetrahedral intermediate, representing the structure during acetyl transfer. Our structural data show that WecD does not possess a residue that directly functions as a catalytic base, although Tyr208 is well positioned to function as a general acid by protonating the thiolate anion of coenzyme A.

  18. Acetyl-L-carnitine protects neuronal function from alcohol-induced oxidative damage in the brain

    PubMed Central

    Rump, Travis J.; Muneer, P.M. Abdul; Szlachetka, Adam M.; Lamb, Allyson; Haorei, Catherine; Alikunju, Saleena; Xiong, Huangui; Keblesh, James; Liu, Jianuo; Zimmerman, Matthew C.; Jones, Jocelyn; Donohue, Terrence M.; Persidsky, Yuri; Haorah, James

    2011-01-01

    The studies presented here demonstrate the protective effect of acetyl-L-carnitine (ALC) against alcohol-induced oxidative neuroinflammation, neuronal degeneration, and impaired neurotransmission. Our findings reveal the cellular and biochemical mechanisms of alcohol-induced oxidative damage in various types of brain cells. Chronic ethanol administration to mice caused an increase in inducible nitric oxide synthase (iNOS) and 3-nitrotyrosine adduct formation in frontal cortical neurons but not in astrocytes from brains of these animals. Interestingly, alcohol administration caused a rather selective activation of NADPH oxidase (NOX), which, in turn, enhanced levels of reactive oxygen species (ROS) and 4-hydroxynonenal, but these were predominantly localized in astrocytes and microglia. Oxidative damage in glial cells was accompanied by their pronounced activation (astrogliosis) and coincident neuronal loss, suggesting that inflammation in glial cells caused neuronal degeneration. Immunohistochemistry studies indicated that alcohol consumption induced different oxidative mediators in different brain cell types. Thus, nitric oxide was mostly detected in iNOS-expressing neurons, whereas ROS were predominantly generated in NOX-expressing glial cells after alcohol ingestion. Assessment of neuronal activity in ex vivo frontal cortical brain tissue slices from ethanol-fed mice showed a reduction in long-term potentiation synaptic transmission compared with slices from controls. Coadministration of ALC with alcohol showed a significant reduction in oxidative damage and neuronal loss and a restoration of synaptic neurotransmission in this brain region, suggesting that ALC protects brain cells from ethanol-induced oxidative injury. These findings suggest the potential clinical utility of ALC as a neuroprotective agent that prevents alcohol-induced brain damage and development of neurological disorders. PMID:20708681

  19. Isolation of a mutant Arabidopsis plant that lacks N-acetyl glucosaminyl transferase I and is unable to synthesize Golgi-modified complex N-linked glycans.

    PubMed Central

    von Schaewen, A; Sturm, A; O'Neill, J; Chrispeels, M J

    1993-01-01

    The complex asparagine-linked glycans of plant glycoproteins, characterized by the presence of beta 1-->2 xylose and alpha 1-->3 fucose residues, are derived from typical mannose9(N-acetylglucosamine)2 (Man9GlcNAc2) N-linked glycans through the activity of a series of glycosidases and glycosyl transferases in the Golgi apparatus. By screening leaf extracts with an antiserum against complex glycans, we isolated a mutant of Arabidopsis thaliana that is blocked in the conversion of high-manne to complex glycans. In callus tissues derived from the mutant plants, all glycans bind to concanavalin A. These glycans can be released by treatment with endoglycosidase H, and the majority has the same size as Man5GlcNAc1 glycans. In the presence of deoxymannojirimycin, an inhibitor of mannosidase I, the mutant cells synthesize Man9GlcNAc2 and Man8GlcNAc2 glycans, suggesting that the biochemical lesion in the mutant is not in the biosynthesis of high-mannose glycans in the endoplasmic reticulum but in their modification in the Golgi. Direct enzyme assays of cell extracts show that the mutant cells lack N-acetyl glucosaminyl transferase I, the first enzyme in the pathway of complex glycan biosynthesis. The mutant plants are able to complete their development normally under several environmental conditions, suggesting that complex glycans are not essential for normal developmental processes. By crossing the complex-glycan-deficient strain of A. thaliana with a transgenic strain that expresses the glycoprotein phytohemagglutinin, we obtained a unique strain that synthesizes phytohemagglutinin with two high-mannose glycans, instead of one high-mannose and one complex glycan. PMID:8278542

  20. Protective effect of calpain inhibitor N-acetyl-L-leucyl-L-leucyl-L-norleucinal on acute alcohol consumption related cardiomyopathy.

    PubMed

    Kartkaya, Kazim; Kanbak, Güngör; Oğlakçı, Ayşegül; Burukoğlu, Dilek; Ozer, Mehmet Caner

    2014-10-01

    Excessive alcohol consumption and alcoholism cause medical problems with high mortality and morbidity rates. In this study we aimed to decrease the alcohol related tissue damage by inhibiting calpain activation which plays an important role in apoptosis and necrosis, in rats with cardiomyopathy induced by acute alcohol consumption. Male Sprague-Dawley rats were separated into four groups (control, vehicle, alcohol and alcohol + inhibitor) with 10 rats in each. Control group received isocaloric maltose while vehicle group received isocaloric maltose with DMSO, and alcohol group received 8 g/kg absolute ethanol by gavage. Inhibitor group received 20 mg/kg calpain inhibitor 1 intraperitonally prior to alcohol administration. Calpain activities, cathepsin L levels and cytochrome c release rates were significantly increased in alcohol group compared to control group (p < 0.05). Serum CK MB and BNP levels of alcohol group were excessively increased compared to control group (respectively p < 0.001 and p < 0.01). Serum BNP levels of alcohol + inhibitor group were significantly (p < 0.05) decreased compared to alcohol group. In addition to these, histological evaluation of light microscope images and the results of DNA fragmentation and immunohistochemical caspase-3 activity results showed significant improvement of these parameters in alcohol + inhibitor group compared to alcohol group. Results of our biochemical and histological evaluation results revealed that the calpain inhibitor N-acetyl-leu-leu-norleucinal may have an ameliorating effect on acute alcohol consumption related cardiac tissue damage due to its effects on cell death pathways. PMID:24996291

  1. Production of herbicide-resistant transgenic Panax ginseng through the introduction of the phosphinothricin acetyl transferase gene and successful soil transfer.

    PubMed

    Choi, Y E; Jeong, J H; In, J K; Yang, D C

    2003-02-01

    Herbicide-resistant transgenic Panax ginseng plants were produced by introducing the phosphinothricin acetyl transferase (PAT) gene that confers resistance to the herbicide Basta (bialaphos) through Agrobacterium tumefaciens co-cultivation. Embryogenic callus gathered from cotyledon explants of P. ginseng were pre-treated with 0.5 M sucrose or 0.05 M MgSO(4 )before Agrobacterium infection. This pre-treatment process markedly enhanced the transient expression of the beta-glucuronidase (GUS) gene. Embryogenic callus was initially cultured on MS medium supplemented with 400 mg/l cefotaxime for 3 weeks and subsequently subcultured five times to a medium containing 25 mg/l kanamycin and 300 mg/l cefotaxime. Somatic embryos formed on the surfaces of kanamycin-resistant callus. Upon development into the cotyledonary stage, these somatic embryos were transferred to a medium containing 50 mg/l kanamycin and 5 mg/l gibberellic acid to induce germination and strong selection. Integration of the transgene into the plants was confirmed by polymerase chain reaction and Southern analyses. Transfer of the transgenic ginseng plantlets to soil was successfully accomplished via acclimatization in autoclaved perlite. Not all of the plantlets survived in soil that had not been autoclaved because of fungal infection, particularly in the region between the roots and leaves. Transgenic plants growing in soil were observed to be strongly resistant to Basta application. PMID:12789431

  2. N-acetyl-cysteine prevents age-related hearing loss and the progressive loss of inner hair cells in γ-glutamyl transferase 1 deficient mice

    PubMed Central

    Ding, Dalian; Jiang, Haiyan; Chen, Guang-Di; Longo-Guess, Chantal; Muthaiah, Vijaya Prakash Krishnan; Tian, Cong; Sheppard, Adam; Salvi, Richard; Johnson, Kenneth R.

    2016-01-01

    Genetic factors combined with oxidative stress are major determinants of age-related hearing loss (ARHL), one of the most prevalent disorders of the elderly. Dwarf grey mice, Ggt1dwg/dwg, are homozygous for a loss of function mutation of the γ-glutamyl transferase 1 gene, which encodes an important antioxidant enzyme critical for the resynthesis of glutathione (GSH). Since GSH reduces oxidative damage, we hypothesized that Ggt1dwg/dwg mice would be susceptible to ARHL. Surprisingly, otoacoustic emissions and cochlear microphonic potentials, which reflect cochlear outer hair cell (OHC) function, were largely unaffected in mutant mice, whereas auditory brainstem responses and the compound action potential were grossly abnormal. These functional deficits were associated with an unusual and selective loss of inner hair cells (IHC), but retention of OHC and auditory nerve fibers. Remarkably, hearing deficits and IHC loss were completely prevented by N-acetyl-L-cysteine, which induces de novo synthesis of GSH; however, hearing deficits and IHC loss reappeared when treatment was discontinued. Ggt1dwg/dwgmice represent an important new model for investigating ARHL, therapeutic interventions, and understanding the perceptual and electrophysiological consequences of sensory deprivation caused by the loss of sensory input exclusively from IHC. PMID:26977590

  3. The association of alcohol intake with gamma-glutamyl transferase (GGT) levels: evidence for correlated genetic effects

    PubMed Central

    van Beek, Jenny H.D.A.; de Moor, Marleen H.M.; Geels, Lot M.; Sinke, Michel R.T.; de Geus, Eco. J.C.; Lubke, Gitta H.; Kluft, Cornelis; Neuteboom, Jacoline; Vink, Jacqueline M.; Willemsen, Gonneke; Boomsma, Dorret I.

    2014-01-01

    Background Blood levels of gamma-glutamyl transferase (GGT) are used as a marker for (heavy) alcohol use. The role of GGT in the anti-oxidant defense mechanism that is part of normal metabolism supposes a causal effect of alcohol intake on GGT. However, there is variability in the response of GGT to alcohol use, which may result from genetic differences between individuals. This study aimed to determine whether the epidemiological association between alcohol intake and GGT at the population level is necessarily a causal one or may also reflect effects of genetic pleiotropy (genes influencing multiple traits). Methods Data on alcohol intake (grams alcohol/day) and GGT, originating from twins, their siblings and parents (N=6,465), were analyzed with structural equation models. Bivariate genetic models tested whether genetic and environmental factors influencing alcohol intake and GGT correlated significantly. Significant genetic and environmental correlations are consistent with a causal model. If only the genetic correlation is significant, this is evidence for genetic pleiotropy. Results Phenotypic correlations between alcohol intake and GGT were significant in men (r=.17) and women (r=.09). The genetic factors underlying alcohol intake correlated significantly with those for GGT, whereas the environmental factors were weakly correlated (explaining 4-7% vs. 1-2% of the variance in GGT respectively). Conclusions In this healthy population sample, the epidemiological association of alcohol intake with GGT is at least partly explained by genetic pleiotropy. Future longitudinal twin studies should determine whether a causal mechanism underlying this association might be confined to heavy drinking populations. PMID:24120856

  4. Metabolic engineering of Escherichia coli for production of biodiesel from fatty alcohols and acetyl-CoA.

    PubMed

    Guo, Daoyi; Pan, Hong; Li, Xun

    2015-09-01

    Microbial production of biodiesel from renewable feedstock has attracted intensive attention. Biodiesel is known to be produced from short-chain alcohols and fatty acyl-CoAs through the expression of wax ester synthase/fatty acyl-CoA: diacylglycerol acyltransferase that catalyzes the esterification of short-chain alcohols and fatty acyl-CoAs. Here, we engineered Escherichia coli to produce various fatty alcohol acetate esters, which depend on the expression of Saccharomyces cerevisiae alcohol acetyltransferase ATF1 that catalyzes the esterification of fatty alcohols and acetyl-CoA. The fatty acid biosynthetic pathways generate fatty acyl-ACPs, fatty acyl-CoAs, or fatty acids, which can be converted to fatty alcohols by fatty acyl-CoA reductase, fatty acyl-ACP reductase, or carboxylic acid reductase, respectively. This study showed the biosynthesis of biodiesel from three fatty acid biosynthetic pathway intermediates.

  5. Identification and suppression of the p-coumaroyl CoA:hydroxycinnamyl alcohol transferase in Zea mays L.

    PubMed

    Marita, Jane M; Hatfield, Ronald D; Rancour, David M; Frost, Kenneth E

    2014-06-01

    Grasses, such as Zea mays L. (maize), contain relatively high levels of p-coumarates (pCA) within their cell walls. Incorporation of pCA into cell walls is believed to be due to a hydroxycinnamyl transferase that couples pCA to monolignols. To understand the role of pCA in maize development, the p-coumaroyl CoA:hydroxycinnamyl alcohol transferase (pCAT) was isolated and purified from maize stems. Purified pCAT was subjected to partial trypsin digestion, and peptides were sequenced by tandem mass spectrometry. TBLASTN analysis of the acquired peptide sequences identified a single full-length maize cDNA clone encoding all the peptide sequences obtained from the purified enzyme. The cDNA clone was obtained and used to generate an RNAi construct for suppressing pCAT expression in maize. Here we describe the effects of suppression of pCAT in maize. Primary screening of transgenic maize seedling leaves using a new rapid analytical platform was used to identify plants with decreased amounts of pCA. Using this screening method, mature leaves from fully developed plants were analyzed, confirming reduced pCA levels throughout plant development. Complete analysis of isolated cell walls from mature transgenic stems and leaves revealed that lignin levels did not change, but pCA levels decreased and the lignin composition was altered. Transgenic plants with the lowest levels of pCA had decreased levels of syringyl units in the lignin. Thus, altering the levels of pCAT expression in maize leads to altered lignin composition, but does not appear to alter the total amount of lignin present in the cell walls.

  6. Identification and suppression of the p-coumaroyl CoA:hydroxycinnamyl alcohol transferase in Zea mays L.

    PubMed Central

    Marita, Jane M; Hatfield, Ronald D; Rancour, David M; Frost, Kenneth E

    2014-01-01

    Grasses, such as Zea mays L. (maize), contain relatively high levels of p-coumarates (pCA) within their cell walls. Incorporation of pCA into cell walls is believed to be due to a hydroxycinnamyl transferase that couples pCA to monolignols. To understand the role of pCA in maize development, the p-coumaroyl CoA:hydroxycinnamyl alcohol transferase (pCAT) was isolated and purified from maize stems. Purified pCAT was subjected to partial trypsin digestion, and peptides were sequenced by tandem mass spectrometry. TBLASTN analysis of the acquired peptide sequences identified a single full-length maize cDNA clone encoding all the peptide sequences obtained from the purified enzyme. The cDNA clone was obtained and used to generate an RNAi construct for suppressing pCAT expression in maize. Here we describe the effects of suppression of pCAT in maize. Primary screening of transgenic maize seedling leaves using a new rapid analytical platform was used to identify plants with decreased amounts of pCA. Using this screening method, mature leaves from fully developed plants were analyzed, confirming reduced pCA levels throughout plant development. Complete analysis of isolated cell walls from mature transgenic stems and leaves revealed that lignin levels did not change, but pCA levels decreased and the lignin composition was altered. Transgenic plants with the lowest levels of pCA had decreased levels of syringyl units in the lignin. Thus, altering the levels of pCAT expression in maize leads to altered lignin composition, but does not appear to alter the total amount of lignin present in the cell walls. PMID:24654730

  7. The synergy of tobacco and alcohol and glutathione S-transferase θ 1 gene deletion and oral squamous cell carcinoma

    PubMed Central

    D’ Mello, Sarah; Bavle, Radhika Manoj; Paremala, K; Makarla, Soumya; Sudhakara, M; Bhatt, Madhura

    2016-01-01

    Background: Oral squamous cell carcinoma (OSCC) is the leading cancer among males in India. It is related to tobacco habits and alcohol consumption as well as the individual susceptibility for xenobiotic metabolizing enzyme polymorphisms. Glutathione S-transferase θ 1 (GSTT1) is a Phase II metabolic enzyme which is directly involved in catalyzing chemicals to mutagenic intermediates. This gene is characterized by genetic polymorphism resulting in complete gene deletion and subsequent absence of the enzyme, which ultimately dictates the risk of cancer development. Scraping buccal mucosa to obtain DNA from the cells is a simple, readily acceptable and rapid method to detect and assess the gene. Aim: To assess GSTT1 gene deletion in individuals giving a history of tobacco smoking and/or chewing and alcohol consumption and absence of clinically detectable lesions; and in OSCC cases to gauge if GSTT1 gene deletion confers protection to an individual and whether it can be used as a “single” marker to arrive at this conclusion. To validate the use of buccal scrape for determining the genotype of an individual by assessing the polymorphism at GSTT1 gene locus (22q11.2). Materials and Methods: Fifty-two cases were evaluated using buccal mucosal scrapes of tobacco habituates for 8 or more years, without clinically evident lesion (Group I) and from mucosa of tobacco habituates with clinically evident and histopathologically confirmed OSCC (Group II). DNA extraction and genotype at GSTT1 gene locus was determined by polymerase chain reaction assay. Statistical Analysis: The results were statistically analyzed using Chi-square test. Results: 90.66% of subjects had GSTT1 null genotype in Group I subjects. In Group II, subjects with both clinically and histopathologically diagnosed oral cancer, about 76.96% had GSTT1 null genotype. Conclusion: GSTT1 null genotype confers protection to individuals with tobacco habits and alcohol consumption, predominantly to those who used

  8. Three alcohol dehydrogenase genes and one acetyl-CoA synthetase gene are responsible for ethanol utilization in Yarrowia lipolytica.

    PubMed

    Gatter, Michael; Ottlik, Stephanie; Kövesi, Zsolt; Bauer, Benjamin; Matthäus, Falk; Barth, Gerold

    2016-10-01

    The non-conventional yeast Yarrowia lipolytica is able to utilize a wide range of different substrates like glucose, glycerol, ethanol, acetate, proteins and various hydrophobic molecules. Although most metabolic pathways for the utilization of these substrates have been clarified by now, it was not clear whether ethanol is oxidized by alcohol dehydrogenases or by an alternative oxidation system inside the cell. In order to detect the genes that are required for ethanol utilization in Y. lipolytica, eight alcohol dehydrogenase (ADH) genes and one alcohol oxidase gene (FAO1) have been identified and respective deletion strains were tested for their ability to metabolize ethanol. As a result of this, we found that the availability of ADH1, ADH2 or ADH3 is required for ethanol utilization in Y. lipolytica. A strain with deletions in all three genes is lacking the ability to utilize ethanol as sole carbon source. Although Adh2p showed by far the highest enzyme activity in an in vitro assay, the availability of any of the three genes was sufficient to enable a decent growth. In addition to ADH1, ADH2 and ADH3, an acetyl-CoA synthetase encoding gene (ACS1) was found to be essential for ethanol utilization. As Y. lipolytica is a non-fermenting yeast, it is neither able to grow under anaerobic conditions nor to produce ethanol. To investigate whether Y. lipolytica may produce ethanol, the key genes of alcoholic fermentation in S. cerevisiae, ScADH1 and ScPDC1, were overexpressed in an ADH and an ACS1 deletion strain. However, instead of producing ethanol, the respective strains regained the ability to use ethanol as single carbon source and were still not able to grow under anaerobic conditions. PMID:27486067

  9. Three alcohol dehydrogenase genes and one acetyl-CoA synthetase gene are responsible for ethanol utilization in Yarrowia lipolytica.

    PubMed

    Gatter, Michael; Ottlik, Stephanie; Kövesi, Zsolt; Bauer, Benjamin; Matthäus, Falk; Barth, Gerold

    2016-10-01

    The non-conventional yeast Yarrowia lipolytica is able to utilize a wide range of different substrates like glucose, glycerol, ethanol, acetate, proteins and various hydrophobic molecules. Although most metabolic pathways for the utilization of these substrates have been clarified by now, it was not clear whether ethanol is oxidized by alcohol dehydrogenases or by an alternative oxidation system inside the cell. In order to detect the genes that are required for ethanol utilization in Y. lipolytica, eight alcohol dehydrogenase (ADH) genes and one alcohol oxidase gene (FAO1) have been identified and respective deletion strains were tested for their ability to metabolize ethanol. As a result of this, we found that the availability of ADH1, ADH2 or ADH3 is required for ethanol utilization in Y. lipolytica. A strain with deletions in all three genes is lacking the ability to utilize ethanol as sole carbon source. Although Adh2p showed by far the highest enzyme activity in an in vitro assay, the availability of any of the three genes was sufficient to enable a decent growth. In addition to ADH1, ADH2 and ADH3, an acetyl-CoA synthetase encoding gene (ACS1) was found to be essential for ethanol utilization. As Y. lipolytica is a non-fermenting yeast, it is neither able to grow under anaerobic conditions nor to produce ethanol. To investigate whether Y. lipolytica may produce ethanol, the key genes of alcoholic fermentation in S. cerevisiae, ScADH1 and ScPDC1, were overexpressed in an ADH and an ACS1 deletion strain. However, instead of producing ethanol, the respective strains regained the ability to use ethanol as single carbon source and were still not able to grow under anaerobic conditions.

  10. Histone acetyl transferase 1 is essential for mammalian development, genome stability, and the processing of newly synthesized histones H3 and H4.

    PubMed

    Nagarajan, Prabakaran; Ge, Zhongqi; Sirbu, Bianca; Doughty, Cheryl; Agudelo Garcia, Paula A; Schlederer, Michaela; Annunziato, Anthony T; Cortez, David; Kenner, Lukas; Parthun, Mark R

    2013-06-01

    Histone acetyltransferase 1 is an evolutionarily conserved type B histone acetyltransferase that is thought to be responsible for the diacetylation of newly synthesized histone H4 on lysines 5 and 12 during chromatin assembly. To understand the function of this enzyme in a complex organism, we have constructed a conditional mouse knockout model of Hat1. Murine Hat1 is essential for viability, as homozygous deletion of Hat1 results in neonatal lethality. The lungs of embryos and pups genetically deficient in Hat1 were much less mature upon histological evaluation. The neonatal lethality is due to severe defects in lung development that result in less aeration and respiratory distress. Many of the Hat1(-/-) neonates also display significant craniofacial defects with abnormalities in the bones of the skull and jaw. Hat1(-/-) mouse embryonic fibroblasts (MEFs) are defective in cell proliferation and are sensitive to DNA damaging agents. In addition, the Hat1(-/-) MEFs display a marked increase in genome instability. Analysis of histone dynamics at sites of replication-coupled chromatin assembly demonstrates that Hat1 is not only responsible for the acetylation of newly synthesized histone H4 but is also required to maintain the acetylation of histone H3 on lysines 9, 18, and 27 during replication-coupled chromatin assembly.

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

    PubMed Central

    Burdette, D; Zeikus, J G

    1994-01-01

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

  12. A novel one-pot and one-step microwave-assisted cyclization-methylation reaction of amino alcohols and acetylated derivatives with dimethyl carbonate and TBAC.

    PubMed

    Ochoa-Terán, Adrián; Guerrero, Leticia; Rivero, Ignacio A

    2014-01-01

    A simple and efficient microwave-assisted methodology for the synthesis of 4-substituted-3-methyl-1,3-oxazolidin-2-ones from amino alcohols catalyzed by a ionic liquid was developed. This novel one-pot and one-step cyclization-methylation reaction represents an easier and faster method than any other reported protocols that can be used to obtain the desired products in good yields and high purity. Applying microwave irradiation at 130°C in the presence of TBAC, dimethyl carbonate acts simultaneously as carbonylating and methylating agent and surprisingly promotes an in situ basic trans esterification when a N-acetylated amino alcohol is used as starting material. Furthermore, dimethyl carbonate worked better than diethyl carbonate in performing this reaction. PMID:25692177

  13. A Novel One-Pot and One-Step Microwave-Assisted Cyclization-Methylation Reaction of Amino Alcohols and Acetylated Derivatives with Dimethyl Carbonate and TBAC

    PubMed Central

    Ochoa-Terán, Adrián; Guerrero, Leticia; Rivero, Ignacio A.

    2014-01-01

    A simple and efficient microwave-assisted methodology for the synthesis of 4-substituted-3-methyl-1,3-oxazolidin-2-ones from amino alcohols catalyzed by a ionic liquid was developed. This novel one-pot and one-step cyclization-methylation reaction represents an easier and faster method than any other reported protocols that can be used to obtain the desired products in good yields and high purity. Applying microwave irradiation at 130°C in the presence of TBAC, dimethyl carbonate acts simultaneously as carbonylating and methylating agent and surprisingly promotes an in situ basic trans esterification when a N-acetylated amino alcohol is used as starting material. Furthermore, dimethyl carbonate worked better than diethyl carbonate in performing this reaction. PMID:25692177

  14. Diagnostic value of alcoholic liver disease (ALD)/nonalcoholic fatty liver disease (NAFLD) index combined with γ-glutamyl transferase in differentiating ALD and NAFLD

    PubMed Central

    Wang, Junling; Li, Ping; Jiang, Zhilong; Yang, Qiuhui; Mi, Yuqiang; Liu, Yonggang; Shi, Ruifang; Zhou, Yonghe; Wang, Jinsheng; Lu, Wei; Li, Si; Liu, Dan

    2016-01-01

    Background/Aims: This study aimed to verify the reliability of the alcoholic liver disease (ALD)/nonalcoholic fatty liver disease (NAFLD) index (ANI) for distinguishing ALD in patients with hepatic steatosis from NAFLD, and to investigate whether ANI combined with γ-glutamyl transferase (GGT) would enhance the accuracy of diagnosis in China. Methods: A hundred thirty-nine cases of fatty liver disease (FLD) were divided into two groups of ALD and NAFLD. The ANI was calculated with an online calculator. All indicators and ANI values were analyzed using statistical methods. Results: ANI was significantly higher in patients with ALD than in those with NAFLD (7.11 ± 5.77 vs. –3.09 ± 3.89, p < 0.001). With a cut-off value of –0.22, the sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) of diagnosed ALD cases was 87.1%, 92.5%, and 0.934 (95% confidence interval [CI], 0.879 to 0.969), respectively. The corresponding values for aspartate aminotransferase (AST)/alanine transaminase (ALT), mean corpuscular volume (MCV), and GGT were 75.29%, 72.94%, and 0.826 (95% CI, 0.752 to 0.885); 94.34%, 83.02%, and 0.814 (95% CI, 0.739 to 0.875) and 80.23%, 79.25%, and 0.815 (95% CI, 0.740 to 0.876), respectively. ANI AUROC was significantly higher than the AST/ALT, MCV, or GGT AUROCs (all p < 0.001), moreover, ANI showed better diagnostic performance. The combination of ANI and GGT showed a better AUROC than ANI alone (0.976 vs. 0.934, p = 0.016). The difference in AUROCs between AST/ALT, MCV, and GGT was not statistically significant (all p > 0.05). Conclusions: ANI can help distinguish ALD from NAFLD with high accuracy; when ANI was combined with GGT, its effectiveness improved further. PMID:27025268

  15. Chronic ethanol consumption induces mitochondrial protein acetylation and oxidative stress in the kidney

    PubMed Central

    Harris, Peter S.; Roy, Samantha R.; Coughlan, Christina; Orlicky, David J.; Liang, Yongliang; Shearn, Colin T.; Roede, James R.; Fritz, Kristofer S.

    2015-01-01

    In this study, we present the novel findings that chronic ethanol consumption induces mitochondrial protein hyperacetylation in the kidney and correlates with significantly increased renal oxidative stress. A major proteomic footprint of alcoholic liver disease (ALD) is an increase in hepatic mitochondrial protein acetylation. Protein hyperacetylation has been shown to alter enzymatic function of numerous proteins and plays a role in regulating metabolic processes. Renal mitochondrial targets of hyperacetylation include numerous metabolic and antioxidant pathways, such as lipid metabolism, oxidative phosphorylation, and amino acid metabolism, as well as glutathione and thioredoxin pathways. Disruption of protein lysine acetylation has the potential to impair renal function through metabolic dysregulation and decreased antioxidant capacity. Due to a significant elevation in ethanol-mediated renal oxidative stress, we highlight the acetylation of superoxide dismutase, peroxiredoxins, glutathione reductase, and glutathione transferase enzymes. Since oxidative stress is a known factor in ethanol-induced nephrotoxicity, we examined biochemical markers of protein hyperacetylation and oxidative stress. Our results demonstrate increased protein acetylation concurrent with depleted glutathione, altered Cys redox potential, and the presence of 4-HNE protein modifications in our 6-week model of early-stage alcoholic nephrotoxicity. These findings support the hypothesis that ethanol metabolism causes an influx of mitochondrial metabolic substrate, resulting in mitochondrial protein hyperacetylation with the potential to impact mitochondrial metabolic and antioxidant processes. PMID:26177469

  16. Alcohol

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Alcohol KidsHealth > For Teens > Alcohol Print A A A ... you can make an educated choice. What Is Alcohol? Alcohol is created when grains, fruits, or vegetables ...

  17. Acetyl chloride

    Integrated Risk Information System (IRIS)

    Acetyl chloride ; CASRN 75 - 36 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  18. Alcohol

    MedlinePlus

    ... Text Size: A A A Listen En Español Alcohol Wondering if alcohol is off limits with diabetes? Most people with diabetes can have a moderate amount of alcohol. Research has shown that there can be some ...

  19. Alcohol

    MedlinePlus

    If you are like many Americans, you drink alcohol at least occasionally. For many people, moderate drinking ... risky. Heavy drinking can lead to alcoholism and alcohol abuse, as well as injuries, liver disease, heart ...

  20. Alcohol

    MedlinePlus

    ... Got Homework? Here's Help White House Lunch Recipes Alcohol KidsHealth > For Kids > Alcohol Print A A A Text Size What's in ... What Is Alcoholism? Say No en español El alcohol Getting the Right Message "Hey, who wants a ...

  1. Alcoholism

    PubMed Central

    Girard, Donald E.; Carlton, Bruce E.

    1978-01-01

    There are important measurements of alcoholism that are poorly understood by physicians. Professional attitudes toward alcoholic patients are often counterproductive. Americans spend about $30 billion on alcohol a year and most adults drink alcohol. Even though traditional criteria allow for recognition of the disease, diagnosis is often made late in the natural course, when intervention fails. Alcoholism is a major health problem and accounts for 10 percent of total health care costs. Still, this country's 10 million adult alcoholics come from a pool of heavy drinkers with well defined demographic characteristics. These social, cultural and familial traits, along with subtle signs of addiction, allow for earlier diagnosis. Although these factors alone do not establish a diagnosis of alcoholism, they should alert a physician that significant disease may be imminent. Focus must be directed to these aspects of alcoholism if containment of the problem is expected. PMID:685264

  2. Alcohol.

    ERIC Educational Resources Information Center

    Schibeci, Renato

    1996-01-01

    Describes the manufacturing of ethanol, the effects of ethanol on the body, the composition of alcoholic drinks, and some properties of ethanol. Presents some classroom experiments using ethanol. (JRH)

  3. Inhibition of Different Histone Acetyltransferases (HATs) Uncovers Transcription-Dependent and -Independent Acetylation-Mediated Mechanisms in Memory Formation

    ERIC Educational Resources Information Center

    Merschbaecher, Katja; Hatko, Lucyna; Folz, Jennifer; Mueller, Uli

    2016-01-01

    Acetylation of histones changes the efficiency of the transcription processes and thus contributes to the formation of long-term memory (LTM). In our comparative study, we used two inhibitors to characterize the contribution of different histone acetyl transferases (HATs) to appetitive associative learning in the honeybee. For one we applied…

  4. Acetate:succinate CoA-transferase in the hydrogenosomes of Trichomonas vaginalis: identification and characterization.

    PubMed

    van Grinsven, Koen W A; Rosnowsky, Silke; van Weelden, Susanne W H; Pütz, Simone; van der Giezen, Mark; Martin, William; van Hellemond, Jaap J; Tielens, Aloysius G M; Henze, Katrin

    2008-01-18

    Acetate:succinate CoA-transferases (ASCT) are acetate-producing enzymes in hydrogenosomes, anaerobically functioning mitochondria and in the aerobically functioning mitochondria of trypanosomatids. Although acetate is produced in the hydrogenosomes of a number of anaerobic microbial eukaryotes such as Trichomonas vaginalis, no acetate producing enzyme has ever been identified in these organelles. Acetate production is the last unidentified enzymatic reaction of hydrogenosomal carbohydrate metabolism. We identified a gene encoding an enzyme for acetate production in the genome of the hydrogenosome-containing protozoan parasite T. vaginalis. This gene shows high similarity to Saccharomyces cerevisiae acetyl-CoA hydrolase and Clostridium kluyveri succinyl-CoA:CoA-transferase. Here we demonstrate that this protein is expressed and is present in the hydrogenosomes where it functions as the T. vaginalis acetate:succinate CoA-transferase (TvASCT). Heterologous expression of TvASCT in CHO cells resulted in the expression of an active ASCT. Furthermore, homologous overexpression of the TvASCT gene in T. vaginalis resulted in an equivalent increase in ASCT activity. It was shown that the CoA transferase activity is succinate-dependent. These results demonstrate that this acetyl-CoA hydrolase/transferase homolog functions as the hydrogenosomal ASCT of T. vaginalis. This is the first hydrogenosomal acetate-producing enzyme to be identified. Interestingly, TvASCT does not share any similarity with the mitochondrial ASCT from Trypanosoma brucei, the only other eukaryotic succinate-dependent acetyl-CoA-transferase identified so far. The trichomonad enzyme clearly belongs to a distinct class of acetate:succinate CoA-transferases. Apparently, two completely different enzymes for succinate-dependent acetate production have evolved independently in ATP-generating organelles. PMID:18024431

  5. αTAT1 controls longitudinal spreading of acetylation marks from open microtubules extremities

    PubMed Central

    Ly, Nathalie; Elkhatib, Nadia; Bresteau, Enzo; Piétrement, Olivier; Khaled, Mehdi; Magiera, Maria M.; Janke, Carsten; Le Cam, Eric; Rutenberg, Andrew D.; Montagnac, Guillaume

    2016-01-01

    Acetylation of the lysine 40 of α-tubulin (K40) is a post-translational modification occurring in the lumen of microtubules (MTs) and is controlled by the α-tubulin acetyl-transferase αTAT1. How αTAT1 accesses the lumen and acetylates α-tubulin there has been an open question. Here, we report that acetylation starts at open ends of MTs and progressively spreads longitudinally from there. We observed acetylation marks at the open ends of in vivo MTs re-growing after a Nocodazole block, and acetylated segments growing in length with time. Bias for MTs extremities was even more pronounced when using non-dynamic MTs extracted from HeLa cells. In contrast, K40 acetylation was mostly uniform along the length of MTs reconstituted from purified tubulin in vitro. Quantitative modelling of luminal diffusion of αTAT1 suggested that the uniform acetylation pattern observed in vitro is consistent with defects in the MT lattice providing lateral access to the lumen. Indeed, we observed that in vitro MTs are permeable to macromolecules along their shaft while cellular MTs are not. Our results demonstrate αTAT1 enters the lumen from open extremities and spreads K40 acetylation marks longitudinally along cellular MTs. This mode of tip-directed microtubule acetylation may allow for selective acetylation of subsets of microtubules. PMID:27752143

  6. Modifications of cell signalling and redox balance by targeting protein acetylation using natural and engineered molecules: implications in cancer therapy.

    PubMed

    Venkateswaran, Kavya; Verma, Amit; Bhatt, Anant N; Agrawala, Paban K; Raj, Hanumantharao G; Malhotra, Shashwat; Prasad, Ashok K; Wever, Olivier De; Bracke, Marc E; Saso, Luciano; Parmar, Virinder S; Shrivastava, Anju; Dwarakanath, B S

    2014-01-01

    Acetylation of proteins with the addition of an acetyl group on the lysine residue is one of the vital posttranslational modifications that regulate protein stability, function and intracellular compartmentalization. Like other posttranslational modifications, protein acetylation influences many if not all vital functions of the cell. Protein acetylation has been originally associated with histone acetylation regulated by Histone Acetyl Transferase (HAT) and Histone Deacetylase (HDAC) and was mainly considered to be involved in epigenetic regulation through chromatin remodelling. It is now widely referred to as lysine acetylation orchestrated by lysine acetyl transferase (KAT) and lysine deacetylase (KDAC) and influences many cellular functions. Protein acetylation fine tunes the redox balance and cell signalling in the context of cancer by exerting its control on expression of two very important redox sensors viz. Nrf2 and NF-κB. Accumulating evidences show that inhibitors of deacetylase (KDACi), responsible for cytotoxic effects in cancer cells, mediate their actions by inhibiting the deacetylases, thereby simulating an hyperacetylation state of histone as well as non-histone proteins, similar to the one created by KATs. Emergence of calreticulin (CRT) mediated protein acetylation system using polyphenolic acetates as donors coupled with over expression of CRT has opened new avenues for targeting protein acetylation for improving cancer therapy. Modifiers of protein acetylation are therefore, emerging as a class of anticancer therapeutics and adjuvant as they inhibit growth, induce differentiation and death (apoptosis) differentially in cancer cells and also exhibit chemo-radiation sensitizing potential. Although pre-clinical investigations with many natural and synthetic KDAC inhibitors have been very promising, their clinical utility has so far been limited to certain types of cancers of the hematopoietic system. The future of protein acetylation modifiers

  7. Polymorphisms in glutathione S-transferases GSTM1, GSTT1 and GSTP1 and cytochromes P450 CYP2E1 and CYP1A1 and susceptibility to cirrhosis or pancreatitis in alcoholics.

    PubMed

    Burim, Regislaine Valéria; Canalle, Renata; Martinelli, Ana de Lôurdes Candolo; Takahashi, Catarina Satie

    2004-07-01

    Excessive alcohol consumption may cause the development of pathologies in the liver and pancreas and various digestive tract cancers. The enzymes GSTM1, GSTT1, GSTP1, CYP1A1 and CYP2E1 are involved in the bioactivation and detoxification of a variety of xenobiotics present in food, organic solvents, tobacco smoke, drugs, pesticides, environmental pollutants and alcoholic drinks. Polymorphisms in the genes coding for these enzymes have been associated with susceptibility to different diseases, including ethanol-related diseases. To investigate whether these polymorphisms represent risk-modifying factors for ethanol-related diseases, a study was conducted involving 120 Brazilian alcoholics and 221 controls with similar ethnic backgrounds. The distribution of alcoholics groups was as follows: 65 with liver cirrhosis, 14 with chronic pancreatitis and 41 without cirrhosis or pancreatitis. The data revealed that carriers of the rare GSTP1 Val allele were at higher risk of liver cirrhosis and pancreatitis, since we found higher frequencies of the Val/Val genotype in alcoholics with liver cirrhosis (15.4%) and pancreatitis (28.6%) in comparison with alcoholics without disease (7.3%). No differences were found in the prevalences of the GSTM1 and GSTT1 null genotypes between alcoholics and the controls and no association was found between the rare CYP2E1 c2 allele and liver cirrhosis and pancreatitis. However, when the mutant CYP1A1 allele was compared between alcoholics and controls, the m2/m2 genotype was more prevalent in the liver cirrhosis alcoholics (7.7%) than in the controls (1.4%) and this difference was statistically significant (P = 0.03, OR = 5.33). In conclusion, our data indicate an association between occurrence of the Val/Val GSTP1 genotype and chronic pancreatitis and an association between the m2/m2 CYP1A1 genotype and alcoholic liver cirrhosis. This could indicate that persons with these genotypes are genetically more prone to the development of alcoholic

  8. Leucine-684: A conserved residue of an AMP-acetyl CoA synthetase (AceCS) from Leishmania donovani is involved in substrate recognition, catalysis and acetylation.

    PubMed

    Soumya, Neelagiri; Tandan, Hitendra; Damre, Mangesh V; Gangwal, Rahul P; Sangamwar, Abhay T; Singh, Sushma

    2016-04-15

    AMP-acetyl CoA synthetase (AMP-AceCS) is a key enzyme which catalyzes the activation of acetate to acetyl CoA, an important intermediate at the cross roads of various anabolic and catabolic pathways. Multiple sequence alignment of Leishmania donovani AceCS with other organisms revealed the presence of a highly conserved leucine residue at 684 position which is known to be crucial for acetylation by protein acetyl transferases in other organisms. In an attempt to understand the role of leucine residue at 684 position in L. donovani acetyl CoA synthetase (LdAceCS), it was mutated to proline (P) by site directed mutagenesis. Kinetic analysis of the L684P-LdAceCS mutant revealed approximately two fold increased binding affinity with acetate, whereas fivefold decreased affinity was observed with ATP. There was insignificant change in secondary structure as revealed by CD however, two fold decreased fluorescence intensity was observed at an emission maxima of 340 nm. Interestingly, L684P mutation abolished the acetylation of the mutant enzyme indicating the importance of L684 in acetylation of the enzyme. Changes in biochemical parameters of the mutant protein were validated by homology modeling of the wild type and mutant LdAceCS enzyme using Salmonella enterica AceCS crystal structure as template. Our data provides evidence for the role of leucine 684 residue in substrate recognition, catalysis and acetylation of the AceCS enzyme.

  9. Acetylation of cyclin-dependent kinase 5 is mediated by GCN5

    SciTech Connect

    Lee, Juhyung; Yun, Nuri; Kim, Chiho; Song, Min-Young; Park, Kang-Sik; Oh, Young J.

    2014-04-25

    Highlights: • Cyclin-dependent kinase 5 (CDK5) is present as an acetylated form. • CDK5 is acetylated by GCN5. • CDK5’s acetylation site is mapped at Lys33. • Its acetylation may affect CDK5’s kinase activity. - Abstract: Cyclin-dependent kinase 5 (CDK5), a member of atypical serine/threonine cyclin-dependent kinase family, plays a crucial role in pathophysiology of neurodegenerative disorders. Its kinase activity and substrate specificity are regulated by several independent pathways including binding with its activator, phosphorylation and S-nitrosylation. In the present study, we report that acetylation of CDK5 comprises an additional posttranslational modification within the cells. Among many candidates, we confirmed that its acetylation is enhanced by GCN5, a member of the GCN5-related N-acetyl-transferase family of histone acetyltransferase. Co-immunoprecipitation assay and fluorescent localization study indicated that GCN5 physically interacts with CDK5 and they are co-localized at the specific nuclear foci. Furthermore, liquid chromatography in conjunction with a mass spectrometry indicated that CDK5 is acetylated at Lys33 residue of ATP binding domain. Considering this lysine site is conserved among a wide range of species and other related cyclin-dependent kinases, therefore, we speculate that acetylation may alter the kinase activity of CDK5 via affecting efficacy of ATP coordination.

  10. Glutathione transferases and neurodegenerative diseases.

    PubMed

    Mazzetti, Anna Paola; Fiorile, Maria Carmela; Primavera, Alessandra; Lo Bello, Mario

    2015-03-01

    There is substantial agreement that the unbalance between oxidant and antioxidant species may affect the onset and/or the course of a number of common diseases including Parkinson's and Alzheimer's diseases. Many studies suggest a crucial role for oxidative stress in the first phase of aging, or in the pathogenesis of various diseases including neurological ones. Particularly, the role exerted by glutathione and glutathione-related enzymes (Glutathione Transferases) in the nervous system appears more relevant, this latter tissue being much more vulnerable to toxins and oxidative stress than other tissues such as liver, kidney or muscle. The present review addresses the question by focusing on the results obtained by specimens from patients or by in vitro studies using cells or animal models related to Parkinson's and Alzheimer's diseases. In general, there is an association between glutathione depletion and Parkinson's or Alzheimer's disease. In addition, a significant decrease of glutathione transferase activity in selected areas of brain and in ventricular cerebrospinal fluid was found. For some glutathione transferase genes there is also a correlation between polymorphisms and onset/outcome of neurodegenerative diseases. Thus, there is a general agreement about the protective effect exerted by glutathione and glutathione transferases but no clear answer about the mechanisms underlying this crucial role in the insurgence of neurodegenerative diseases.

  11. An Smc3 Acetylation Cycle Is Essential for Establishment of Sister Chromatid Cohesion

    PubMed Central

    Beckouët, Frederic; Hu, Bin; Roig, Maurici B.; Sutani, Takashi; Komata, Makiko; Uluocak, Pelin; Katis, Vittorio L.; Shirahige, Katsuhiko; Nasmyth, Kim

    2015-01-01

    SUMMARY Sister chromatid cohesion is thought to involve entrapment of sister DNAs by a tripartite ring composed of the cohesin subunits Smc1, Smc3, and Scc1. Establishment of cohesion during S phase depends on acetylation of Smc3’s nucleotide-binding domain (NBD) by the Eco1 acetyl transferase. It is destroyed at the onset of anaphase due to Scc1 cleavage by separase. In yeast, Smc3 acetylation is reversed at anaphase by the Hos1 deacetylase as a consequence of Scc1 cleavage. Smc3 molecules that remain acetylated after mitosis due to Hos1 inactivation cannot generate cohesion during the subsequent S phase, implying that cohesion establishment depends on de novo acetylation during DNA replication. By inducing Smc3 deacetylation in postreplicative cells due to Hos1 overexpression, we provide evidence that Smc3 acetylation contributes to the maintenance of sister chromatid cohesion. A cycle of Smc3 NBD acetylation is therefore an essential aspect of the chromosome cycle in eukaryotic cells. PMID:20832721

  12. Feruloyl-CoA:monolignol transferase

    DOEpatents

    Wilkerson, Curtis; Ralph, John; Withers, Saunia; Mansfield, Shawn D.

    2016-09-13

    The invention relates to nucleic acids encoding a feruloyl-CoA:monolignol transferase and the feruloyl-CoA:monolignol transferase enzyme that enables incorporation of monolignol ferulates, for example, including p-coumaryl ferulate, coniferyl ferulate, and sinapyl ferulate, into the lignin of plants.

  13. Histone acetylation: truth of consequences?

    PubMed

    Choi, Jennifer K; Howe, Leann J

    2009-02-01

    Eukaryotic DNA is packaged into a nucleoprotein structure known as chromatin, which is comprised of DNA, histones, and nonhistone proteins. Chromatin structure is highly dynamic, and can shift from a transcriptionally inactive state to an active form in response to intra- and extracellular signals. A major factor in chromatin architecture is the covalent modification of histones through the addition of chemical moieties, such as acetyl, methyl, ubiquitin, and phosphate groups. The acetylation of the amino-terminal tails of histones is a process that is highly conserved in eukaryotes, and was one of the earliest histone modifications characterized. Since its identification in 1964, a large body of evidence has accumulated demonstrating that histone acetylation plays an important role in transcription. Despite our ever-growing understanding of the nuclear processes involved in nucleosome acetylation, however, the exact biochemical mechanisms underlying the downstream effects of histone acetylation have yet to be fully elucidated. To date, histone acetylation has been proposed to function in 2 nonmutually exclusive manners: by directly altering chromatin structure, and by acting as a molecular tag for the recruitment of chromatin-modifying complexes. Here, we discuss recent research focusing on these 2 potential roles of histone acetylation and clarify what we actually know about the function of this modification.

  14. Glutathione transferases: a structural perspective.

    PubMed

    Oakley, Aaron

    2011-05-01

    The glutathione transferases (GSTs) are one of the most important families of detoxifying enzymes in nature. The classic activity of the GSTs is conjugation of compounds with electrophilic centers to the tripeptide glutathione (GSH), but many other activities are now associated with GSTs, including steroid and leukotriene biosynthesis, peroxide degradation, double-bond cis-trans isomerization, dehydroascorbate reduction, Michael addition, and noncatalytic "ligandin" activity (ligand binding and transport). Since the first GST structure was determined in 1991, there has been an explosion in structural data across GSTs of all three families: the cytosolic GSTs, the mitochondrial GSTs, and the membrane-associated proteins in eicosanoid and glutathione metabolism (MAPEG family). In this review, the major insights into GST structure and function will be discussed.

  15. Alamethicin biosynthesis: acetylation of the amino terminus and attachment of phenylalaninol.

    PubMed

    Mohr, H; Kleinkauf, H

    1978-10-12

    Alamethicin synthetase was extracted from the fungus Trichoderma viride at the end of its exponential growth phase. It is multienzyme complex with a molecular weight of approx. 480 000. The biosynthesis of alamethicin is initiated on the synthetase by acetylation of thiolester-bound aminoisobutyric acid, which remains enzyme bound. Acetyl-CoA serves as the acetate donor. Of the alamethicin constituents, glycine, alanine and valine are also acetylated when incubated alone. This acetylation is prevented by added aminoisobutyric acid, which indicates that the site on alamethicin synthetase catalyzing the acetylation has a preference for aminoisobutyric acid. Alamethicin formation on the synthetase is terminated by linkage of phenylalaninol to the carboxyl terminus of the peptide. It is unlikely that the amino alcohol is a degradation product of alamethicin or that it had been split off from the synthetase complex. Thus it is probably the reaction product of a separate enzyme system. PMID:568941

  16. Urinary mutagenicity and N-acetylation phenotype in textile industry workers exposed to arylamines

    SciTech Connect

    Sinues, B.; Perez, J.; Bernal, M.L.; Saenz, M.A.; Lanuza, J.; Bartolome, M. )

    1992-09-15

    Primary aromatic amines have been identified epidemiologically as human carcinogens. It has been suggested that the target organ affected by aromatic amines is dependent on the rate of metabolic activation. Epidemiological studies have shown an association between low acetyl transferase activity and bladder cancer risk. On this basis, our working hypothesis was that the slow acetylators could follow in a higher extent the metabolic pathway independent of N-acetylation, leading to the excretion of conjugates of electrophyles with glucuronic acid. The instability of these glucuronides could be responsible for the association between arylamine-induced bladder cancer and slow acetylator phenotype. A total of 153 individuals were included in this study: 70 exposed to arylamines (working in textile industry) and 83 nonexposed. The following parameters were determined in urine: mutagenic index in the absence of metabolic activation, S9; mutagenic index in the presence of S9; and the mutagenic index after incubation of the urine with beta-glucuronidase. All individuals were phenotyped according to their capacity of N-acetylation by using isoniazid as drug test. The results show that the mutagenic index after incubation of the urine with beta-glucuronidase is statistically higher in exposed subjects when compared with nonexposed individuals (P less than 0.001), this parameter being statistically higher among exposed subjects who were slow acetylators than among rapid metabolizers, independent of the fact that they were smokers or nonsmokers. There were no significant differences between groups for the mutagenicity in urine not incubated with beta-glucuronidase.

  17. Alcoholism and Alcohol Abuse

    MedlinePlus

    ... This means that their drinking causes distress and harm. It includes alcoholism and alcohol abuse. Alcoholism, or ... brain, and other organs. Drinking during pregnancy can harm your baby. Alcohol also increases the risk of ...

  18. Acetylator phenotype in diabetic neuropathy.

    PubMed

    McLaren, E H; Burden, A C; Moorhead, P J

    1977-07-30

    The proportions of slow and fast acetylators in a group of diabetics with symptomatic peripheral neuropathy were compared with those in a group of diabetics who had had the disease for at least 10 years without developing neuropathy. There was a significantly higher proportion of fast acetylators in the group of diabetics without neuropathy than in those with neuropathy or in the normal population. Hence genetic factors separate from the diabetic diathesis may determine the development of neuropathy in any particular diabetic.

  19. Genetic polymorphism of N-acetyltransferases, glutathione S-transferase M1 and NAD(P)H:quinone oxidoreductase in relation to malignant and benign pancreatic disease risk. The International Pancreatic Disease Study Group.

    PubMed

    Bartsch, H; Malaveille, C; Lowenfels, A B; Maisonneuve, P; Hautefeuille, A; Boyle, P

    1998-06-01

    Carcinogens present in cigarette smoke and diet have been associated with pancreatic cancer. We hypothesized that heterocyclic and aromatic amines implicated in these exposures could be involved as causative agents and that therefore genetic variation in enzymes metabolizing these carcinogens could modify the risk of developing malignant and benign pancreatic disease. The effect of the genetic polymorphism of acetyltransferases (NAT1) and NAT2), glutathione S-transferase M1 (GSTM1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) on the risk of pancreatic diseases (cancer, pancreatitis) was examined in a case-control study. PCR-based assays were used for genotype analysis of genomic DNA from whole blood cells. Samples collected from Caucasian patients with diagnosed pancreatic cancer (n = 81), with non-alcoholic (n = 41) and alcoholic pancreatitis (n = 73) and from asymptomatic control subjects (n = 78) were analysed. The prevalence of GSTM1 null genotype and of NAT2 fast and slow acetylator genotypes and the distribution of frequencies for NQO1 genotypes did not differ in subjects with pancreatic diseases vs controls. For NAT1 slow acetylators a non-significant excess (P = 0.18) was found among pancreatic cancer cases vs controls. There was a significant over-representation of the GSTM1 AB or B genotype in all pancreatic disease cases combined (OR = 2.6; P < 0.05). When concurrent controls were pooled with literature controls (n = 1427), OR was 1.4 (P = 0.08). The results of this study, requiring confirmation, suggest that the polymorphism of GSTM1 and NAT1 enzymes may be associated with a modest increase in susceptibility to pancreatic diseases.

  20. Functional Dissection of the Bipartite Active Site of the Class I Coenzyme A (CoA)-Transferase Succinyl-CoA:Acetate CoA-Transferase.

    PubMed

    Murphy, Jesse R; Mullins, Elwood A; Kappock, T Joseph

    2016-01-01

    Coenzyme A (CoA)-transferases catalyze the reversible transfer of CoA from acyl-CoA thioesters to free carboxylates. Class I CoA-transferases produce acylglutamyl anhydride intermediates that undergo attack by CoA thiolate on either the internal or external carbonyl carbon atoms, forming distinct tetrahedral intermediates <3 Å apart. In this study, crystal structures of succinyl-CoA:acetate CoA-transferase (AarC) from Acetobacter aceti are used to examine how the Asn347 carboxamide stabilizes the internal oxyanion intermediate. A structure of the active mutant AarC-N347A bound to CoA revealed both solvent replacement of the missing contact and displacement of the adjacent Glu294, indicating that Asn347 both polarizes and orients the essential glutamate. AarC was crystallized with the nonhydrolyzable acetyl-CoA (AcCoA) analog dethiaacetyl-CoA (1a) in an attempt to trap a closed enzyme complex containing a stable analog of the external oxyanion intermediate. One active site contained an acetylglutamyl anhydride adduct and truncated 1a, an unexpected result hinting at an unprecedented cleavage of the ketone moiety in 1a. Solution studies confirmed that 1a decomposition is accompanied by production of near-stoichiometric acetate, in a process that seems to depend on microbial contamination but not AarC. A crystal structure of AarC bound to the postulated 1a truncation product (2a) showed complete closure of one active site per dimer but no acetylglutamyl anhydride, even with acetate added. These findings suggest that an activated acetyl donor forms during 1a decomposition; a working hypothesis involving ketone oxidation is offered. The ability of 2a to induce full active site closure furthermore suggests that it subverts a system used to impede inappropriate active site closure on unacylated CoA.

  1. Functional dissection of the bipartite active site of the class I coenzyme A (CoA)-transferase succinyl-CoA:acetate CoA-transferase

    NASA Astrophysics Data System (ADS)

    Murphy, Jesse; Mullins, Elwood; Kappock, T.

    2016-05-01

    Coenzyme A (CoA)-transferases catalyze the reversible transfer of CoA from acyl-CoA thioesters to free carboxylates. Class I CoA-transferases produce acylglutamyl anhydride intermediates that undergo attack by CoA thiolate on either the internal or external carbonyl carbon atoms, forming distinct tetrahedral intermediates less than 3 Å apart. In this study, crystal structures of succinyl-CoA:acetate CoA-transferase (AarC) from Acetobacter aceti are used to examine how the Asn347 carboxamide stabilizes the internal oxyanion intermediate. A structure of the active mutant AarC-N347A bound to CoA revealed both solvent replacement of the missing contact and displacement of the adjacent Glu294, indicating that Asn347 both polarizes and orients the essential glutamate. AarC was crystallized with the nonhydrolyzable acetyl-CoA (AcCoA) analogue dethiaacetyl-CoA (1a) in an attempt to trap a closed enzyme complex containing a stable analogue of the external oxyanion intermediate. One active site contained an acetylglutamyl anhydride adduct and truncated 1a, an unexpected result hinting at an unprecedented cleavage of the ketone moiety in 1a. Solution studies confirmed that 1a decomposition is accompanied by production of near-stoichiometric acetate, in a process that seems to depend on microbial contamination but not AarC. A crystal structure of AarC bound to the postulated 1a truncation product (2a) showed complete closure of one active site per dimer but no acetylglutamyl anhydride, even with acetate added. These findings suggest that an activated acetyl donor forms during 1a decomposition; a working hypothesis involving ketone oxidation is offered. The ability of 2a to induce full active site closure furthermore suggests that it subverts a system used to impede inappropriate active site closure on unacylated CoA.

  2. Functional Dissection of the Bipartite Active Site of the Class I Coenzyme A (CoA)-Transferase Succinyl-CoA:Acetate CoA-Transferase

    PubMed Central

    Murphy, Jesse R.; Mullins, Elwood A.; Kappock, T. Joseph

    2016-01-01

    Coenzyme A (CoA)-transferases catalyze the reversible transfer of CoA from acyl-CoA thioesters to free carboxylates. Class I CoA-transferases produce acylglutamyl anhydride intermediates that undergo attack by CoA thiolate on either the internal or external carbonyl carbon atoms, forming distinct tetrahedral intermediates <3 Å apart. In this study, crystal structures of succinyl-CoA:acetate CoA-transferase (AarC) from Acetobacter aceti are used to examine how the Asn347 carboxamide stabilizes the internal oxyanion intermediate. A structure of the active mutant AarC-N347A bound to CoA revealed both solvent replacement of the missing contact and displacement of the adjacent Glu294, indicating that Asn347 both polarizes and orients the essential glutamate. AarC was crystallized with the nonhydrolyzable acetyl-CoA (AcCoA) analog dethiaacetyl-CoA (1a) in an attempt to trap a closed enzyme complex containing a stable analog of the external oxyanion intermediate. One active site contained an acetylglutamyl anhydride adduct and truncated 1a, an unexpected result hinting at an unprecedented cleavage of the ketone moiety in 1a. Solution studies confirmed that 1a decomposition is accompanied by production of near-stoichiometric acetate, in a process that seems to depend on microbial contamination but not AarC. A crystal structure of AarC bound to the postulated 1a truncation product (2a) showed complete closure of one active site per dimer but no acetylglutamyl anhydride, even with acetate added. These findings suggest that an activated acetyl donor forms during 1a decomposition; a working hypothesis involving ketone oxidation is offered. The ability of 2a to induce full active site closure furthermore suggests that it subverts a system used to impede inappropriate active site closure on unacylated CoA. PMID:27242998

  3. Inhibition of Histone H3K9 Acetylation by Anacardic Acid Can Correct the Over-Expression of Gata4 in the Hearts of Fetal Mice Exposed to Alcohol during Pregnancy

    PubMed Central

    Peng, Chang; Zhu, Jing; Sun, Hui-Chao; Huang, Xu-Pei; Zhao, Wei-An; Zheng, Min; Liu, Ling-Juan; Tian, Jie

    2014-01-01

    Background Cardiovascular malformations can be caused by abnormalities in Gata4 expression during fetal development. In a previous study, we demonstrated that ethanol exposure could lead to histone hyperacetylation and Gata4 over-expression in fetal mouse hearts. However, the potential mechanisms of histone hyperacetylation and Gata4 over-expression induced by ethanol remain unclear. Methods and Results Pregnant mice were gavaged with ethanol or saline. Fetal mouse hearts were collected for analysis. The results of ethanol fed groups showed that global HAT activity was unusually high in the hearts of fetal mice while global HDAC activity remained unchanged. Binding of P300, CBP, PCAF, SRC1, but not GCN5, were increased on the Gata4 promoter relative to the saline treated group. Increased acetylation of H3K9 and increased mRNA expression of Gata4, α-MHC, cTnT were observed in these hearts. Treatment with the pan-histone acetylase inhibitor, anacardic acid, reduced the binding of P300, PCAF to the Gata4 promoter and reversed H3K9 hyperacetylation in the presence of ethanol. Interestingly, anacardic acid attenuated over-expression of Gata4, α-MHC and cTnT in fetal mouse hearts exposed to ethanol. Conclusions Our results suggest that P300 and PCAF may be critical regulatory factors that mediate Gata4 over-expression induced by ethanol exposure. Alternatively, P300, PCAF and Gata4 may coordinate over-expression of cardiac downstream genes in mouse hearts exposed to ethanol. Anacardic acid may thus protect against ethanol-induced Gata4, α-MHC, cTnT over-expression by inhibiting the binding of P300 and PCAF to the promoter region of these genes. PMID:25101666

  4. Fatal Intoxication with Acetyl Fentanyl.

    PubMed

    Cunningham, Susan M; Haikal, Nabila A; Kraner, James C

    2016-01-01

    Among the new psychoactive substances encountered in forensic investigations is the opioid, acetyl fentanyl. The death of a 28-year-old man from recreational use of this compound is reported. The decedent was found in the bathroom of his residence with a tourniquet secured around his arm and a syringe nearby. Postmortem examination findings included marked pulmonary and cerebral edema and needle track marks. Toxicological analysis revealed acetyl fentanyl in subclavian blood, liver, vitreous fluid, and urine at concentrations of 235 ng/mL, 2400 ng/g, 131 ng/mL, and 234 ng/mL, respectively. Acetyl fentanyl was also detected in the accompanying syringe. Death was attributed to recreational acetyl fentanyl abuse, likely through intravenous administration. The blood acetyl fentanyl concentration is considerably higher than typically found in fatal fentanyl intoxications. Analysis of this case underscores the need for consideration of a wide range of compounds with potential opioid-agonist activity when investigating apparent recreational drug-related deaths. PMID:26389815

  5. Effect of glutathione S-transferase M1 polymorphisms on biomarkers of exposure and effects.

    PubMed Central

    Srám, R J

    1998-01-01

    Genotypes responsible for interindividual differences in ability to activate or detoxify genotoxic agents are recognized as biomarkers of susceptibility. Among the most studied genotypes are human glutathione transferases. The relationship of genetic susceptibility to biomarkers of exposure and effects was studied especially in relation to the genetic polymorphism of glutathione S-transferase M1 (GSTM1). For this review papers reporting the effect of GSTM1 genotype on DNA adducts, protein adducts, urine mutagenicity, Comet assay parameters, chromosomal aberrations, sister chromatid exchanges (SCE), micronuclei, and hypoxanthine-guanine phosphoribosyl transferase mutations were assessed. Subjects in groups occupationally exposed to polycyclic aromatic hydrocarbons, benzidine, pesticides, and 1,3-butadiene were included. As environmentally exposed populations, autopsy donors, coal tar-treated patients, smokers, nonsmokers, mothers, postal workers, and firefighters were followed. From all biomarkers the effect of GSTM1 and N-acetyl transferase 2 was seen in coke oven workers on mutagenicity of urine and of glutathione S-transferase T1 on the chromosomal aberrations in subjects from 1,3-butadiene monomer production units. Effects of genotypes on DNA adducts were found from lung tissue of autopsy donors and from placentas of mothers living in an air-polluted region. The GSTM1 genotype affected mutagenicity of urine in smokers and subjects from polluted regions, protein adducts in smokers, SCE in smokers and nonsmokers, and Comet assay parameters in postal workers. A review of all studies on GSTM1 polymorphisms suggests that research probably has not reached the stage where results can be interpreted to formulate preventive measures. The relationship between genotypes and biomarkers of exposure and effects may provide an important guide to the risk assessment of human exposure to mutagens and carcinogens. PMID:9539016

  6. Oxygen-dependent acetylation and dimerization of the corepressor CtBP2 in neural stem cells

    SciTech Connect

    Karaca, Esra; Lewicki, Jakub; Hermanson, Ola

    2015-03-01

    The transcriptional corepressor CtBP2 is essential for proper development of the nervous system. The factor exerts its repression by interacting in complexes with chromatin-modifying factors such as histone deacetylases (HDAC) 1/2 and the histone demethylase LSD1/KDM1. Notably, the histone acetyl transferase p300 acetylates CtBP2 and this is an important regulatory event of the activity and subcellular localization of the protein. We recently demonstrated an essential role for CtBPs as sensors of microenvironmental oxygen levels influencing the differentiation potential of neural stem cells (NSCs), but it is not known whether oxygen levels influence the acetylation levels of CtBP factors. Here we show by using proximity ligation assay (PLA) that CtBP2 acetylation levels increased significantly in undifferentiated, proliferating NSCs under hypoxic conditions. CtBP2 interacted with the class III HDAC Sirt1 but this interaction was unaltered in hypoxic conditions, and treatment with the Sirt1 inhibitor Ex527 did not result in any significant change in total CtBP2 acetylation levels. Instead, we revealed a significant decrease in PLA signal representing CtBP2 dimerization in NSCs under hypoxic conditions, negatively correlating with the acetylation levels. Our results suggest that microenvironmental oxygen levels influence the dimerization and acetylation levels, and thereby the activity, of CtBP2 in proliferating NSCs.

  7. Sirt1 physically interacts with Tip60 and negatively regulates Tip60-mediated acetylation of H2AX

    SciTech Connect

    Yamagata, Kazutsune; Kitabayashi, Issay

    2009-12-25

    Sirt1 appear to be NAD(+)-dependent deacetylase that deacetylates histones and several non-histone proteins. In this study, we identified Sirt1 as a physical interaction partner of Tip60, which is a mammalian MYST-type histone acetyl-transferase that specifically acetylates histones H2A and H4. Although Tip60 also acetylates DNA damage-specific histone H2A variant H2AX in response to DNA damage, which is a process required for appropriate DNA damage response, overexpression of Sirt1 represses Tip60-mediated acetylation of H2AX. Furthermore, Sirt1 depletion by RNAi causes excessive acetylation of H2AX, and enhances accumulation of {gamma}-ray irradiation-induced MDC1, BRCA1, and Rad51 foci in nuclei. These findings suggest that Sirt1 functions as negative regulator of Tip60-mediated acetylation of H2AX. Moreover, Sirt1 deacetylates an acetylated Tip60 in response to DNA damage and stimulates proteasome-dependent Tip60 degradation in vivo, suggesting that Sirt1 negatively regulates the protein level of Tip60 in vivo. Sirt1 may thus repress excessive activation of the DNA damage response and Rad51-homologous recombination repair by suppressing the function of Tip60.

  8. Oxygen-dependent acetylation and dimerization of the corepressor CtBP2 in neural stem cells.

    PubMed

    Karaca, Esra; Lewicki, Jakub; Hermanson, Ola

    2015-03-01

    The transcriptional corepressor CtBP2 is essential for proper development of the nervous system. The factor exerts its repression by interacting in complexes with chromatin-modifying factors such as histone deacetylases (HDAC) 1/2 and the histone demethylase LSD1/KDM1. Notably, the histone acetyl transferase p300 acetylates CtBP2 and this is an important regulatory event of the activity and subcellular localization of the protein. We recently demonstrated an essential role for CtBPs as sensors of microenvironmental oxygen levels influencing the differentiation potential of neural stem cells (NSCs), but it is not known whether oxygen levels influence the acetylation levels of CtBP factors. Here we show by using proximity ligation assay (PLA) that CtBP2 acetylation levels increased significantly in undifferentiated, proliferating NSCs under hypoxic conditions. CtBP2 interacted with the class III HDAC Sirt1 but this interaction was unaltered in hypoxic conditions, and treatment with the Sirt1 inhibitor Ex527 did not result in any significant change in total CtBP2 acetylation levels. Instead, we revealed a significant decrease in PLA signal representing CtBP2 dimerization in NSCs under hypoxic conditions, negatively correlating with the acetylation levels. Our results suggest that microenvironmental oxygen levels influence the dimerization and acetylation levels, and thereby the activity, of CtBP2 in proliferating NSCs.

  9. Three CoA Transferases Involved in the Production of Short Chain Fatty Acids in Porphyromonas gingivalis

    PubMed Central

    Sato, Mitsunari; Yoshida, Yasuo; Nagano, Keiji; Hasegawa, Yoshiaki; Takebe, Jun; Yoshimura, Fuminobu

    2016-01-01

    Butyryl-CoA:acetate CoA transferase, which produces butyrate and acetyl-CoA from butyryl-CoA and acetate, is responsible for the final step of butyrate production in bacteria. This study demonstrates that in the periodontopathogenic bacterium Porphyromonas gingivalis this reaction is not catalyzed by PGN_1171, previously annotated as butyryl-CoA:acetate CoA transferase, but by three distinct CoA transferases, PGN_0725, PGN_1341, and PGN_1888. Gas chromatography/mass spectrometry (GC-MS) and spectrophotometric analyses were performed using crude enzyme extracts from deletion mutant strains and purified recombinant proteins. The experiments revealed that, in the presence of acetate, PGN_0725 preferentially utilized butyryl-CoA rather than propionyl-CoA. By contrast, this preference was reversed in PGN_1888. The only butyryl-CoA:acetate CoA transferase activity was observed in PGN_1341. Double reciprocal plots revealed that all the reactions catalyzed by these enzymes follow a ternary-complex mechanism, in contrast to previously characterized CoA transferases. GC-MS analysis to determine the concentrations of short chain fatty acids (SCFAs) in culture supernatants of P. gingivalis wild type and mutant strains revealed that PGN_0725 and PGN_1888 play a major role in the production of butyrate and propionate, respectively. Interestingly, a triple deletion mutant lacking PGN_0725, PGN_1341, and PGN_1888 produced low levels of SCFAs, suggesting that the microorganism contains CoA transferase(s) in addition to these three enzymes. Growth rates of the mutant strains were mostly slower than that of the wild type, indicating that many carbon compounds produced in the SCFA synthesis appear to be important for the biological activity of this microorganism. PMID:27486457

  10. Three CoA Transferases Involved in the Production of Short Chain Fatty Acids in Porphyromonas gingivalis.

    PubMed

    Sato, Mitsunari; Yoshida, Yasuo; Nagano, Keiji; Hasegawa, Yoshiaki; Takebe, Jun; Yoshimura, Fuminobu

    2016-01-01

    Butyryl-CoA:acetate CoA transferase, which produces butyrate and acetyl-CoA from butyryl-CoA and acetate, is responsible for the final step of butyrate production in bacteria. This study demonstrates that in the periodontopathogenic bacterium Porphyromonas gingivalis this reaction is not catalyzed by PGN_1171, previously annotated as butyryl-CoA:acetate CoA transferase, but by three distinct CoA transferases, PGN_0725, PGN_1341, and PGN_1888. Gas chromatography/mass spectrometry (GC-MS) and spectrophotometric analyses were performed using crude enzyme extracts from deletion mutant strains and purified recombinant proteins. The experiments revealed that, in the presence of acetate, PGN_0725 preferentially utilized butyryl-CoA rather than propionyl-CoA. By contrast, this preference was reversed in PGN_1888. The only butyryl-CoA:acetate CoA transferase activity was observed in PGN_1341. Double reciprocal plots revealed that all the reactions catalyzed by these enzymes follow a ternary-complex mechanism, in contrast to previously characterized CoA transferases. GC-MS analysis to determine the concentrations of short chain fatty acids (SCFAs) in culture supernatants of P. gingivalis wild type and mutant strains revealed that PGN_0725 and PGN_1888 play a major role in the production of butyrate and propionate, respectively. Interestingly, a triple deletion mutant lacking PGN_0725, PGN_1341, and PGN_1888 produced low levels of SCFAs, suggesting that the microorganism contains CoA transferase(s) in addition to these three enzymes. Growth rates of the mutant strains were mostly slower than that of the wild type, indicating that many carbon compounds produced in the SCFA synthesis appear to be important for the biological activity of this microorganism. PMID:27486457

  11. Acetylator phenotype in diabetic neuropathy.

    PubMed Central

    McLaren, E H; Burden, A C; Moorhead, P J

    1977-01-01

    The proportions of slow and fast acetylators in a group of diabetics with symptomatic peripheral neuropathy were compared with those in a group of diabetics who had had the disease for at least 10 years without developing neuropathy. There was a significantly higher proportion of fast acetylators in the group of diabetics without neuropathy than in those with neuropathy or in the normal population. Hence genetic factors separate from the diabetic diathesis may determine the development of neuropathy in any particular diabetic. PMID:871863

  12. Acetylated α-Tubulin Regulated by N-Acetyl-Seryl-Aspartyl-Lysyl-Proline(Ac-SDKP) Exerts the Anti-fibrotic Effect in Rat Lung Fibrosis Induced by Silica.

    PubMed

    Xiaojun, Wang; Yan, Liu; Hong, Xu; Xianghong, Zhang; Shifeng, Li; Dingjie, Xu; Xuemin, Gao; Lijuan, Zhang; Bonan, Zhang; Zhongqiu, Wei; Ruimin, Wang; Brann, Darrell; Fang, Yang

    2016-01-01

    Silicosis is the most serious occupational disease in China. The objective of this study was to screen various proteins related to mechanisms of the pathogenesis of silicosis underlying the anti-fibrotic effect of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) using proteomic profile analysis. We also aimed to explore a potential mechanism of acetylated α-tubulin (α-Ac-Tub) regulation by Ac-SDKP. Two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) were used to assess the different protein expression profiles between control and silicosis rats treated with or without Ac-SDKP. Twenty-nine proteins were identified to be potentially involved in the progression of silicosis and the anti-fibrotic effect of Ac-SDKP. Our current study finds that 1) the lost expression of Ac-Tub-α may be a new mechanism in rat silicosis; 2) treatment of silicotic rats with N-acetyl-Seryl-Aspartyl-Lysyl-Proline (Ac-SDKP) inhibits myofibroblast differentiation and collagen deposition accompanied by stabilizing the expression of α-Ac-Tub in vivo and in vitro, which is related with deacetylase family member 6 (HDAC6) and α-tubulin acetyl transferase (α-TAT1). Our data suggest that α-Ac-Tub regulation by Ac-SDKP may potentially be a new anti-fibrosis mechanism. PMID:27577858

  13. Acetylated α-Tubulin Regulated by N-Acetyl-Seryl-Aspartyl-Lysyl-Proline(Ac-SDKP) Exerts the Anti-fibrotic Effect in Rat Lung Fibrosis Induced by Silica.

    PubMed

    Xiaojun, Wang; Yan, Liu; Hong, Xu; Xianghong, Zhang; Shifeng, Li; Dingjie, Xu; Xuemin, Gao; Lijuan, Zhang; Bonan, Zhang; Zhongqiu, Wei; Ruimin, Wang; Brann, Darrell; Fang, Yang

    2016-08-31

    Silicosis is the most serious occupational disease in China. The objective of this study was to screen various proteins related to mechanisms of the pathogenesis of silicosis underlying the anti-fibrotic effect of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) using proteomic profile analysis. We also aimed to explore a potential mechanism of acetylated α-tubulin (α-Ac-Tub) regulation by Ac-SDKP. Two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) were used to assess the different protein expression profiles between control and silicosis rats treated with or without Ac-SDKP. Twenty-nine proteins were identified to be potentially involved in the progression of silicosis and the anti-fibrotic effect of Ac-SDKP. Our current study finds that 1) the lost expression of Ac-Tub-α may be a new mechanism in rat silicosis; 2) treatment of silicotic rats with N-acetyl-Seryl-Aspartyl-Lysyl-Proline (Ac-SDKP) inhibits myofibroblast differentiation and collagen deposition accompanied by stabilizing the expression of α-Ac-Tub in vivo and in vitro, which is related with deacetylase family member 6 (HDAC6) and α-tubulin acetyl transferase (α-TAT1). Our data suggest that α-Ac-Tub regulation by Ac-SDKP may potentially be a new anti-fibrosis mechanism.

  14. Acetylated α-Tubulin Regulated by N-Acetyl-Seryl-Aspartyl-Lysyl-Proline(Ac-SDKP) Exerts the Anti-fibrotic Effect in Rat Lung Fibrosis Induced by Silica

    PubMed Central

    Xiaojun, Wang; Yan, Liu; Hong, Xu; Xianghong, Zhang; Shifeng, Li; Dingjie, Xu; Xuemin, Gao; Lijuan, Zhang; Bonan, Zhang; Zhongqiu, Wei; Ruimin, Wang; Brann, Darrell; Fang, Yang

    2016-01-01

    Silicosis is the most serious occupational disease in China. The objective of this study was to screen various proteins related to mechanisms of the pathogenesis of silicosis underlying the anti-fibrotic effect of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) using proteomic profile analysis. We also aimed to explore a potential mechanism of acetylated α-tubulin (α-Ac-Tub) regulation by Ac-SDKP. Two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) were used to assess the different protein expression profiles between control and silicosis rats treated with or without Ac-SDKP. Twenty-nine proteins were identified to be potentially involved in the progression of silicosis and the anti-fibrotic effect of Ac-SDKP. Our current study finds that 1) the lost expression of Ac-Tub-α may be a new mechanism in rat silicosis; 2) treatment of silicotic rats with N-acetyl-Seryl-Aspartyl-Lysyl-Proline (Ac-SDKP) inhibits myofibroblast differentiation and collagen deposition accompanied by stabilizing the expression of α-Ac-Tub in vivo and in vitro, which is related with deacetylase family member 6 (HDAC6) and α-tubulin acetyl transferase (α-TAT1). Our data suggest that α-Ac-Tub regulation by Ac-SDKP may potentially be a new anti-fibrosis mechanism. PMID:27577858

  15. Reconsolidation involves histone acetylation depending on the strength of the memory.

    PubMed

    Federman, N; Fustiñana, M S; Romano, A

    2012-09-01

    Gene expression is a necessary step for memory re-stabilization after retrieval, a process known as reconsolidation. Histone acetylation is a fundamental mechanism involved in epigenetic regulation of gene expression and has been implicated in memory consolidation. However, few studies are available in reconsolidation, all of them in vertebrate models. Additionally, the recruitment of histone acetylation as a function of different memory strengths has not been systematically analyzed before. Here we studied the role of histone acetylation in reconsolidation using a well-characterized memory model in invertebrate, the context-signal memory in the crab Chasmagnathus. Firstly, we found an increase in histone H3 acetylation 1h after memory reactivation returning to basal levels at 3 h. Strikingly, this increment was only detected during reconsolidation of a long-term memory induced by a strong training of 30 trials, but not for a short-term memory formed by a weak training of five trials or for a long-term memory induced by a standard training of 15 trials. Furthermore, we showed that a weak memory which was enhanced during consolidation by histone deacetylases inhibition, also recruited histone H3 acetylation in reconsolidation as the strong training does. Accordingly, we found the first evidence that the administration of a histone acetyl transferase inhibitor during memory reconsolidation impairs long-term memory re-stabilization. Finally, we found that strong training memory, at variance with the standard training memory, was resistant to extinction, indicating that such strong training induced in fact a stronger memory. In conclusion, the results presented here support that the participation of histone acetylation during reconsolidation is an evolutionary conserved feature and constitutes a specific molecular characteristic of strong memories.

  16. Mapping sugar beet pectin acetylation pattern.

    PubMed

    Ralet, Marie-Christine; Cabrera, Juan Carlos; Bonnin, Estelle; Quéméner, Bernard; Hellìn, Pilar; Thibault, Jean-François

    2005-08-01

    Homogalacturonan-derived partly methylated and/or acetylated oligogalacturonates were recovered after enzymatic hydrolysis (endo-polygalacturonase+pectin methyl esterase+side-chain degrading enzymes) of sugar beet pectin followed by anion-exchange and size exclusion chromatography. Around 90% of the GalA and 75% of the acetyl groups present in the initial sugar beet pectin were recovered as homogalacturonan-derived oligogalacturonates, the remaining GalA and acetyl belonging to rhamnogalacturonic regions. Around 50% of the acetyl groups present in sugar beet homogalacturonans were recovered as partly methylated and/or acetylated oligogalacturonates of degree of polymerisation 5 whose structures were determined by electrospray ionization ion trap mass spectrometry (ESI-IT-MSn). 2-O-acetyl- and 3-O-acetyl-GalA were detected in roughly similar amounts but 2,3-di-O-acetylation was absent. Methyl-esterified GalA residues occurred mainly upstream 2-O-acetyl GalA. Oligogalacturonates containing GalA residues that are at once methyl- and acetyl-esterified were recovered in very limited amounts. A tentative mapping of the distribution of acetyl and methyl esters within sugar beet homogalacturonans is proposed. Unsubstituted GalA residues are likely to be present in limited amounts (approximately 10% of total GalA residues), due to the fact that methyl and acetyl groups are assumed to be most often not carried by the same residues.

  17. Protein acetylation in archaea, bacteria, and eukaryotes.

    PubMed

    Soppa, Jörg

    2010-09-16

    Proteins can be acetylated at the alpha-amino group of the N-terminal amino acid (methionine or the penultimate amino acid after methionine removal) or at the epsilon-amino group of internal lysines. In eukaryotes the majority of proteins are N-terminally acetylated, while this is extremely rare in bacteria. A variety of studies about N-terminal acetylation in archaea have been reported recently, and it was revealed that a considerable fraction of proteins is N-terminally acetylated in haloarchaea and Sulfolobus, while this does not seem to apply for methanogenic archaea. Many eukaryotic proteins are modified by differential internal acetylation, which is important for a variety of processes. Until very recently, only two bacterial proteins were known to be acetylation targets, but now 125 acetylation sites are known for E. coli. Knowledge about internal acetylation in archaea is extremely limited; only two target proteins are known, only one of which--Alba--was used to study differential acetylation. However, indications accumulate that the degree of internal acetylation of archaeal proteins might be underestimated, and differential acetylation has been shown to be essential for the viability of haloarchaea. Focused proteomic approaches are needed to get an overview of the extent of internal protein acetylation in archaea.

  18. Flow properties of acetylated chickpea protein dispersions.

    PubMed

    Liu, Li H; Hung, Tran V

    2010-06-01

    Chickpea protein concentrate was acetylated with acetic anhydride at 5 levels. Acetylated chickpea protein (ACP) dispersions at 3 levels (6%, 45%, and 49%) were chosen for this flow property study. Effects of protein concentration, temperature, concentrations of salt addition and particularly, degree of acetylation on these properties were examined. Compared with native chickpea proteins, the ACP dispersions exhibited a strong shear thinning behavior. Within measured temperature range (15 to 55 degrees C), the apparent viscosities of native chickpea protein dispersions were temperature independent; those of ACP dispersions were thermally affected. The flow index (n), consistency coefficient (m), apparent yield stress, and apparent viscosities of ACP dispersions increased progressively up to 45% acetylation but decreased at 49% acetylation level. Conformational studies by gel filtration suggested that chickpea proteins were associated or polymerized at up to 45% acetylation but the associated subunits gradually dissociated to smaller units at higher levels (49%) of acetylation.

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

    PubMed Central

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

    2006-01-01

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

  20. [Structure and functions of glutathione transferases].

    PubMed

    Fedets, O M

    2014-01-01

    Data about classification, nomenclature, structure, substrate specificity and role of many glutathione transferase's isoenzymes in cell functions have been summarised. The enzyme has been discovered more than 50 years ago. This family of proteins is updated continuously. It has very different composition and will have demand for system analysis for many years.

  1. Diagnostic characteristics and application of alcohol biomarkers.

    PubMed

    Topic, Aleksandra; Djukic, Mirjana

    2013-01-01

    Alcohol biomarkers play a significant role in the early diagnosis of alcohol intoxication/abuse, alcohol-related organ damages, assessment of alcoholism therapy outcomes, and in forensic medicine. Laboratory detection of excessive alcohol consumption can be carried out by direct measuring of the ethanol and/or metabolites in biological samples which is of particular importance in the cases of acute ethanol intoxication/controlling and/or monitoring of alcohol consumption, or indirectly, by using biomarkers. Preferred diagnostic characteristics of alcohol biomarkers, specificity and sensitivity dependent on the particular demands such as: prevention and treatment of alcoholism in primary and social care, criminal justice, workplace health and safety screening, trafficking control, etc. Alcohol biomarkers traditionally used in clinical practice [blood alcohol concentration (BAC), gamma-glutamyl transferase (GGT), carbohydrate-deficient transferrin (CDT), the ratio GGT/CDT, alanine aminotransferase (ALT), aspartate aminotransferase (AST), the rati. AST/ALT, mean cbrpuscular volume (MCV), phosphatidylethanol (PEth)] are well validated. They are used as screening/monitoring markers of acute/chronic excessive alcohol intake, alcoholism in pregnancy, and other disorders/conditions related to alcohol abuse. Numerous potential alcohol biomarkers have been discovered, but few are validated. Potential alcohol biomarkers (ethanol and serotonin metabolites, sialic acids, etc.) have good diagnostic characteristics, but their application in clinical practice is limited due to the costly equipment necessary for their measurement. Significant progress has been made in the development of sensitive and practical alcohol transdermal devices that can instantly/continuously measure BAC through human skin. Transdermal sensing of alcohol may become a valuable method for monitoring abstinence. A special aspect of alcoholism is genetic predisposition to alcohol abuse and alcoholism, or

  2. Diagnostic characteristics and application of alcohol biomarkers.

    PubMed

    Topic, Aleksandra; Djukic, Mirjana

    2013-01-01

    Alcohol biomarkers play a significant role in the early diagnosis of alcohol intoxication/abuse, alcohol-related organ damages, assessment of alcoholism therapy outcomes, and in forensic medicine. Laboratory detection of excessive alcohol consumption can be carried out by direct measuring of the ethanol and/or metabolites in biological samples which is of particular importance in the cases of acute ethanol intoxication/controlling and/or monitoring of alcohol consumption, or indirectly, by using biomarkers. Preferred diagnostic characteristics of alcohol biomarkers, specificity and sensitivity dependent on the particular demands such as: prevention and treatment of alcoholism in primary and social care, criminal justice, workplace health and safety screening, trafficking control, etc. Alcohol biomarkers traditionally used in clinical practice [blood alcohol concentration (BAC), gamma-glutamyl transferase (GGT), carbohydrate-deficient transferrin (CDT), the ratio GGT/CDT, alanine aminotransferase (ALT), aspartate aminotransferase (AST), the rati. AST/ALT, mean cbrpuscular volume (MCV), phosphatidylethanol (PEth)] are well validated. They are used as screening/monitoring markers of acute/chronic excessive alcohol intake, alcoholism in pregnancy, and other disorders/conditions related to alcohol abuse. Numerous potential alcohol biomarkers have been discovered, but few are validated. Potential alcohol biomarkers (ethanol and serotonin metabolites, sialic acids, etc.) have good diagnostic characteristics, but their application in clinical practice is limited due to the costly equipment necessary for their measurement. Significant progress has been made in the development of sensitive and practical alcohol transdermal devices that can instantly/continuously measure BAC through human skin. Transdermal sensing of alcohol may become a valuable method for monitoring abstinence. A special aspect of alcoholism is genetic predisposition to alcohol abuse and alcoholism, or

  3. Investigating Histone Acetylation Stoichiometry and Turnover Rate.

    PubMed

    Fan, J; Baeza, J; Denu, J M

    2016-01-01

    Histone acetylation is a dynamic epigenetic modification that functions in the regulation of DNA-templated reactions, such as transcription. This lysine modification is reversibly controlled by histone (lysine) acetyltransferases and deacetylases. Here, we present methods employing isotopic labeling and mass spectrometry (MS) to comprehensively investigate histone acetylation dynamics. Turnover rates of histone acetylation are determined by measuring the kinetics of labeling from (13)C-labeled precursors of acetyl-CoA, which incorporates (13)C-carbon onto histones via the acetyltransferase reaction. Overall histone acetylation states are assessed from complete protease digestion to single amino acids, which is followed by MS analysis. Determination of site-specific acetylation stoichiometry is achieved by chemically acetylating endogenous histones with isotopic acetic anhydride, followed by trypsin digestion and LC-MS analysis. Combining metabolic labeling with stoichiometric analysis permits determination of both acetylation level and acetylation dynamics. When comparing genetic, diet, or environmental perturbations, these methods permit both a global and site-specific evaluation of how histone acetylation is dynamically regulated.

  4. Investigating Histone Acetylation Stoichiometry and Turnover Rate.

    PubMed

    Fan, J; Baeza, J; Denu, J M

    2016-01-01

    Histone acetylation is a dynamic epigenetic modification that functions in the regulation of DNA-templated reactions, such as transcription. This lysine modification is reversibly controlled by histone (lysine) acetyltransferases and deacetylases. Here, we present methods employing isotopic labeling and mass spectrometry (MS) to comprehensively investigate histone acetylation dynamics. Turnover rates of histone acetylation are determined by measuring the kinetics of labeling from (13)C-labeled precursors of acetyl-CoA, which incorporates (13)C-carbon onto histones via the acetyltransferase reaction. Overall histone acetylation states are assessed from complete protease digestion to single amino acids, which is followed by MS analysis. Determination of site-specific acetylation stoichiometry is achieved by chemically acetylating endogenous histones with isotopic acetic anhydride, followed by trypsin digestion and LC-MS analysis. Combining metabolic labeling with stoichiometric analysis permits determination of both acetylation level and acetylation dynamics. When comparing genetic, diet, or environmental perturbations, these methods permit both a global and site-specific evaluation of how histone acetylation is dynamically regulated. PMID:27423860

  5. Alcoholism, Alcohol, and Drugs

    ERIC Educational Resources Information Center

    Rubin, Emanuel; Lieber, Charles S.

    1971-01-01

    Describes research on synergistic effects of alcohol and other drugs, particularly barbiturates. Proposes biochemical mechanisms to explain alcoholics' tolerance of other drugs when sober, and increased sensitivity when drunk. (AL)

  6. Analysis of acetylation stoichiometry suggests that SIRT3 repairs nonenzymatic acetylation lesions.

    PubMed

    Weinert, Brian T; Moustafa, Tarek; Iesmantavicius, Vytautas; Zechner, Rudolf; Choudhary, Chunaram

    2015-11-01

    Acetylation is frequently detected on mitochondrial enzymes, and the sirtuin deacetylase SIRT3 is thought to regulate metabolism by deacetylating mitochondrial proteins. However, the stoichiometry of acetylation has not been studied and is important for understanding whether SIRT3 regulates or suppresses acetylation. Using quantitative mass spectrometry, we measured acetylation stoichiometry in mouse liver tissue and found that SIRT3 suppressed acetylation to a very low stoichiometry at its target sites. By examining acetylation changes in the liver, heart, brain, and brown adipose tissue of fasted mice, we found that SIRT3-targeted sites were mostly unaffected by fasting, a dietary manipulation that is thought to regulate metabolism through SIRT3-dependent deacetylation. Globally increased mitochondrial acetylation in fasted liver tissue, higher stoichiometry at mitochondrial acetylation sites, and greater sensitivity of SIRT3-targeted sites to chemical acetylation in vitro and fasting-induced acetylation in vivo, suggest a nonenzymatic mechanism of acetylation. Our data indicate that most mitochondrial acetylation occurs as a low-level nonenzymatic protein lesion and that SIRT3 functions as a protein repair factor that removes acetylation lesions from lysine residues.

  7. Protein acetylation in metabolism - metabolites and cofactors.

    PubMed

    Menzies, Keir J; Zhang, Hongbo; Katsyuba, Elena; Auwerx, Johan

    2016-01-01

    Reversible acetylation was initially described as an epigenetic mechanism regulating DNA accessibility. Since then, this process has emerged as a controller of histone and nonhistone acetylation that integrates key physiological processes such as metabolism, circadian rhythm and cell cycle, along with gene regulation in various organisms. The widespread and reversible nature of acetylation also revitalized interest in the mechanisms that regulate lysine acetyltransferases (KATs) and deacetylases (KDACs) in health and disease. Changes in protein or histone acetylation are especially relevant for many common diseases including obesity, diabetes mellitus, neurodegenerative diseases and cancer, as well as for some rare diseases such as mitochondrial diseases and lipodystrophies. In this Review, we examine the role of reversible acetylation in metabolic control and how changes in levels of metabolites or cofactors, including nicotinamide adenine dinucleotide, nicotinamide, coenzyme A, acetyl coenzyme A, zinc and butyrate and/or β-hydroxybutyrate, directly alter KAT or KDAC activity to link energy status to adaptive cellular and organismal homeostasis.

  8. 2-Acetyl-pyridinium bromanilate.

    PubMed

    Thomas, Lynne H; Boyle, Bryan; Clive, Lesley A; Collins, Anna; Currie, Lynsey D; Gogol, Malgorzata; Hastings, Claire; Jones, Andrew O F; Kennedy, Jennifer L; Kerr, Graham B; Kidd, Alastair; Lawton, Lorreta M; Macintyre, Susan J; Maclean, Niall M; Martin, Alan R G; McGonagle, Kate; Melrose, Samantha; Rew, Gaius A; Robinson, Colin W; Schmidtmann, Marc; Turnbull, Felicity B; Williams, Lewis G; Wiseman, Alan Y; Wocial, Malgorzata H; Wilson, Chick C

    2009-01-01

    In the crystal of the title mol-ecular salt (systematic name: 2-acetyl-pyridinium 2,5-dibromo-4-hydr-oxy-3,6-dioxocyclo-hexa-1,4-dienolate), C(7)H(8)NO(+)·C(6)HBr(2)O(4) (-), centrosymmetric rings consisting of two cations and two anions are formed, with the components linked by alternating O-H⋯O and N-H⋯O hydrogen bonds. Short O⋯Br contacts [3.243 (2) and 3.359 (2) Å] may help to consolidate the packing. PMID:21583087

  9. A Method to determine lysine acetylation stoichiometries

    SciTech Connect

    Nakayasu, Ernesto S.; Wu, Si; Sydor, Michael A.; Shukla, Anil K.; Weitz, Karl K.; Moore, Ronald J.; Hixson, Kim K.; Kim, Jong Seo; Petyuk, Vladislav A.; Monroe, Matthew E.; Pasa-Tolic, Ljiljana; Qian, Weijun; Smith, Richard D.; Adkins, Joshua N.; Ansong, Charles

    2014-07-21

    A major bottleneck to fully understanding the functional aspects of lysine acetylation is the lack of stoichiometry information. Here we describe a mass spectrometry method using a combination of isotope labeling and detection of a diagnostic fragment ion to determine the stoichiometry of lysine acetylation on proteins globally. Using this technique, we determined the modification occupancy on hundreds of acetylated peptides from cell lysates and cross-validated the measurements via immunoblotting.

  10. Isolation and identification of kahweol palmitate and cafestol palmitate as active constituents of green coffee beans that enhance glutathione S-transferase activity in the mouse.

    PubMed

    Lam, L K; Sparnins, V L; Wattenberg, L W

    1982-04-01

    Glutathione (GSH) S-transferase is a major detoxification enzyme system that catalyzes the binding of a variety of electrophiles, including reactive forms of chemical carcinogens, to GSH. Green coffee beans fed in the diet induced increased GSH S-transferase activity in the mucosa of the small intestine and in the liver of mice. A potent compound that induces increased GSH S-transferase activity was isolated from green coffee beans and identified as kahweol palmitate. The corresponding free alcohol, kahweol, and its synthetic monoacetate are also potent inducers of the activity of GSH S-transferase. A similar diterpene ester, cafestol palmitate, isolated from green coffee beans was active but less so than was kahweol palmitate. Likewise, the corresponding alcohol, cafestol, and its monoacetate showed moderate potency as inducers of increased GSH S-transferase activity. Kahweol palmitate and cafestol palmitate were extracted from green coffee beans into petroleum ether. The petroleum ether extract was fractionated by preparative normal-phase and reverse-phase liquid chromatographies successively. Final purification with silver nitrate-impregnated thin-layer chromatography yielded the pure palmitates of cafestol and kahweol. The structures were determined by examination of the spectroscopic data of the esters and their parent alcohols and by derivative comparison. PMID:7059995

  11. Acetylation of woody lignocellulose: significance and regulation

    PubMed Central

    Pawar, Prashant Mohan-Anupama; Koutaniemi, Sanna; Tenkanen, Maija; Mellerowicz, Ewa J.

    2013-01-01

    Non-cellulosic cell wall polysaccharides constitute approximately one quarter of usable biomass for human exploitation. In contrast to cellulose, these components are usually substituted by O-acetyl groups, which affect their properties and interactions with other polymers, thus affecting their solubility and extractability. However, details of these interactions are still largely obscure. Moreover, polysaccharide hydrolysis to constituent monosaccharides is hampered by the presence of O-acetyl groups, necessitating either enzymatic (esterase) or chemical de-acetylation, increasing the costs and chemical consumption. Reduction of polysaccharide acetyl content in planta is a way to modify lignocellulose toward improved saccharification. In this review we: (1) summarize literature on lignocellulose acetylation in different tree species, (2) present data and current hypotheses concerning the role of O-acetylation in determining woody lignocellulose properties, (3) describe plant proteins involved in lignocellulose O-acetylation, (4) give examples of microbial enzymes capable to de-acetylate lignocellulose, and (5) discuss prospects for exploiting these enzymes in planta to modify xylan acetylation. PMID:23734153

  12. Acetylation regulates Jun protein turnover in Drosophila.

    PubMed

    Zhang, Daoyong; Suganuma, Tamaki; Workman, Jerry L

    2013-11-01

    C-Jun is a major transcription factor belonging to the activating protein 1 (AP-1) family. Phosphorylation has been shown to be critical for c-Jun activation and stability. Here, we report that Jra, the Drosophila Jun protein, is acetylated in vivo. We demonstrate that the acetylation of Jra leads to its rapid degradation in response to osmotic stress. Intriguingly, we also found that Jra phosphorylation antagonized its acetylation, indicating the opposite roles of acetylation and phosphorylation in Jra degradation process under osmotic stress. Our results provide new insights into how c-Jun proteins are precisely regulated by the interplay of different posttranslational modifications.

  13. Crystal structures of Acetobacter aceti succinyl-coenzyme A (CoA):acetate CoA-transferase reveal specificity determinants and illustrate the mechanism used by class I CoA-transferases.

    PubMed

    Mullins, Elwood A; Kappock, T Joseph

    2012-10-23

    Coenzyme A (CoA)-transferases catalyze transthioesterification reactions involving acyl-CoA substrates, using an active-site carboxylate to form covalent acyl anhydride and CoA thioester adducts. Mechanistic studies of class I CoA-transferases suggested that acyl-CoA binding energy is used to accelerate rate-limiting acyl transfers by compressing the substrate thioester tightly against the catalytic glutamate [White, H., and Jencks, W. P. (1976) J. Biol. Chem. 251, 1688-1699]. The class I CoA-transferase succinyl-CoA:acetate CoA-transferase is an acetic acid resistance factor (AarC) with a role in a variant citric acid cycle in Acetobacter aceti. In an effort to identify residues involved in substrate recognition, X-ray crystal structures of a C-terminally His(6)-tagged form (AarCH6) were determined for several wild-type and mutant complexes, including freeze-trapped acetylglutamyl anhydride and glutamyl-CoA thioester adducts. The latter shows the acetate product bound to an auxiliary site that is required for efficient carboxylate substrate recognition. A mutant in which the catalytic glutamate was changed to an alanine crystallized in a closed complex containing dethiaacetyl-CoA, which adopts an unusual curled conformation. A model of the acetyl-CoA Michaelis complex demonstrates the compression anticipated four decades ago by Jencks and reveals that the nucleophilic glutamate is held at a near-ideal angle for attack as the thioester oxygen is forced into an oxyanion hole composed of Gly388 NH and CoA N2″. CoA is nearly immobile along its entire length during all stages of the enzyme reaction. Spatial and sequence conservation of key residues indicates that this mechanism is general among class I CoA-transferases.

  14. Conductimetric assays for the hydrolase and transferase activities of phospholipase D enzymes.

    PubMed

    Mezna, M; Lawrence, A J

    1994-05-01

    Measurement of solution electrical conductance (conductimetry) is a simple direct assay method for the protogenic, hydrolytic reactions catalyzed by all phospholipase enzymes. The technique is especially suitable for assay of phospholipase D (PLD) enzymes where cleavage of zwitterionic substrates reinforces the pH dependent conductance change and allows the method to be used over a much wider pH range than the equivalent titrimetric assay. The ability to detect zwitterion cleavage enables the method to assay reactions in which phospholipase D transfers neutral, or anionic, alcohol species to the zwitterionic substrates phosphatidyl choline and phosphatidyl ethanolamine. The method can follow the sequential attack by different phospholipases and provides a simple technique for investigating the effect of substrate structure on susceptibility to various phospholipase enzymes. The results confirm that PLD from Streptomyces chromofuscus can attack lysophospholipids, but cannot transfer primary alcohols to the phosphatidyl residue, while the PLD from savoy cabbage is an efficient transferase, but cannot attack lysophospholipids. The data suggest that the bacterial PLD fails to act as a transferase because it hydrolyzes the transphosphatidylation products. Some phosphatidyl alcohols are more highly susceptible to PLA2 attack than the parent phosphatidyl choline derivatives.

  15. Alcohol Alert

    MedlinePlus

    ... Us You are here Home » Alcohol Alert Alcohol Alert The NIAAA Alcohol Alert is a quarterly bulletin that disseminates important research ... text. To order single copies of select Alcohol Alerts, see ordering Information . To view publications in PDF ...

  16. Alcoholism - resources

    MedlinePlus

    Resources - alcoholism ... The following organizations are good resources for information on alcoholism : Alcoholics Anonymous -- www.aa.org Al-Anon/Alateen -- www.al-anon.org/home National Institute on Alcohol ...

  17. Alcoholic neuropathy

    MedlinePlus

    Neuropathy - alcoholic; Alcoholic polyneuropathy ... The exact cause of alcoholic neuropathy is unknown. It likely includes both a direct poisoning of the nerve by the alcohol and the effect of poor nutrition ...

  18. Alcohol Facts

    MedlinePlus

    ... raquo Alcohol Facts Alcohol Facts Listen Drinks like beer, malt liquor, wine, and hard liquor contain alcohol. Alcohol is the ingredient that gets you drunk. Hard liquor—such as whiskey, rum, or gin—has more ...

  19. Inhibition of different histone acetyltransferases (HATs) uncovers transcription-dependent and -independent acetylation-mediated mechanisms in memory formation.

    PubMed

    Merschbaecher, Katja; Hatko, Lucyna; Folz, Jennifer; Mueller, Uli

    2016-02-01

    Acetylation of histones changes the efficiency of the transcription processes and thus contributes to the formation of long-term memory (LTM). In our comparative study, we used two inhibitors to characterize the contribution of different histone acetyl transferases (HATs) to appetitive associative learning in the honeybee. For one we applied garcinol, an inhibitor of the HATs of the p300 (EP300 binding protein)/CBP (CREB-binding protein) family, and the HATs of the PCAF (p300/CBP-associated factor) family. As comparative agent we applied C646, a specific inhibitor that selectively blocks HATS of the p300/CBP family. Immunochemical analysis reveals differences in histone H3 acetylation in the honeybee brain, in response to the injection of either C646 or garcinol. Behavioral assessment reveals that the two drugs cause memory impairment of different nature when injected after associative conditioning: processes disturbed by garcinol are annihilated by the established transcription blocker actinomycin D and thus seem to require transcription processes. Actions of C646 are unaltered by actinomycin D, and thus seem to be independent of transcription. The outcome of our different approaches as summarized suggests that distinct HATs contribute to different acetylation-mediated processes in memory formation. We further deduce that the acetylation-mediated processes in memory formation comprise transcription-dependent and transcription-independent mechanisms.

  20. A Method to Determine Lysine Acetylation Stoichiometries

    DOE PAGES

    Nakayasu, Ernesto S.; Wu, Si; Sydor, Michael A.; Shukla, Anil K.; Weitz, Karl K.; Moore, Ronald J.; Hixson, Kim K.; Kim, Jong-Seo; Petyuk, Vladislav A.; Monroe, Matthew E.; et al

    2014-01-01

    Lysine acetylation is a common protein posttranslational modification that regulates a variety of biological processes. A major bottleneck to fully understanding the functional aspects of lysine acetylation is the difficulty in measuring the proportion of lysine residues that are acetylated. Here we describe a mass spectrometry method using a combination of isotope labeling and detection of a diagnostic fragment ion to determine the stoichiometry of protein lysine acetylation. Using this technique, we determined the modification occupancy for ~750 acetylated peptides from mammalian cell lysates. Furthermore, the acetylation on N-terminal tail of histone H4 was cross-validated by treating cells with sodiummore » butyrate, a potent deacetylase inhibitor, and comparing changes in stoichiometry levels measured by our method with immunoblotting measurements. Of note we observe that acetylation stoichiometry is high in nuclear proteins, but very low in mitochondrial and cytosolic proteins. In summary, our method opens new opportunities to study in detail the relationship of lysine acetylation levels of proteins with their biological functions.« less

  1. 21 CFR 172.828 - Acetylated monoglycerides.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.828 Acetylated monoglycerides. The food additive acetylated... of catalytic agents that are not food additives or are authorized by regulation, followed by...

  2. SPOTing Acetyl-Lysine Dependent Interactions.

    PubMed

    Picaud, Sarah; Filippakopoulos, Panagis

    2015-08-17

    Post translational modifications have been recognized as chemical signals that create docking sites for evolutionary conserved effector modules, allowing for signal integration within large networks of interactions. Lysine acetylation in particular has attracted attention as a regulatory modification, affecting chromatin structure and linking to transcriptional activation. Advances in peptide array technologies have facilitated the study of acetyl-lysine-containing linear motifs interacting with the evolutionary conserved bromodomain module, which specifically recognizes and binds to acetylated sequences in histones and other proteins. Here we summarize recent work employing SPOT peptide technology to identify acetyl-lysine dependent interactions and document the protocols adapted in our lab, as well as our efforts to characterize such bromodomain-histone interactions. Our results highlight the versatility of SPOT methods and establish an affordable tool for rapid access to potential protein/modified-peptide interactions involving lysine acetylation.

  3. SPOTing Acetyl-Lysine Dependent Interactions

    PubMed Central

    Picaud, Sarah; Filippakopoulos, Panagis

    2015-01-01

    Post translational modifications have been recognized as chemical signals that create docking sites for evolutionary conserved effector modules, allowing for signal integration within large networks of interactions. Lysine acetylation in particular has attracted attention as a regulatory modification, affecting chromatin structure and linking to transcriptional activation. Advances in peptide array technologies have facilitated the study of acetyl-lysine-containing linear motifs interacting with the evolutionary conserved bromodomain module, which specifically recognizes and binds to acetylated sequences in histones and other proteins. Here we summarize recent work employing SPOT peptide technology to identify acetyl-lysine dependent interactions and document the protocols adapted in our lab, as well as our efforts to characterize such bromodomain-histone interactions. Our results highlight the versatility of SPOT methods and establish an affordable tool for rapid access to potential protein/modified-peptide interactions involving lysine acetylation. PMID:27600229

  4. SPOTing Acetyl-Lysine Dependent Interactions

    PubMed Central

    Picaud, Sarah; Filippakopoulos, Panagis

    2015-01-01

    Post translational modifications have been recognized as chemical signals that create docking sites for evolutionary conserved effector modules, allowing for signal integration within large networks of interactions. Lysine acetylation in particular has attracted attention as a regulatory modification, affecting chromatin structure and linking to transcriptional activation. Advances in peptide array technologies have facilitated the study of acetyl-lysine-containing linear motifs interacting with the evolutionary conserved bromodomain module, which specifically recognizes and binds to acetylated sequences in histones and other proteins. Here we summarize recent work employing SPOT peptide technology to identify acetyl-lysine dependent interactions and document the protocols adapted in our lab, as well as our efforts to characterize such bromodomain-histone interactions. Our results highlight the versatility of SPOT methods and establish an affordable tool for rapid access to potential protein/modified-peptide interactions involving lysine acetylation.

  5. Alcohol Alert: Genetics of Alcoholism

    MedlinePlus

    ... and Reports » Alcohol Alert » Alcohol Alert Number 84 Alcohol Alert Number 84 Print Version The Genetics of ... immune defense system. Genes Encoding Enzymes Involved in Alcohol Breakdown Some of the first genes linked to ...

  6. Trypanosomatidae produce acetate via a mitochondrial acetate:succinate CoA transferase.

    PubMed

    Van Hellemond, J J; Opperdoes, F R; Tielens, A G

    1998-03-17

    Hydrogenosome-containing anaerobic protists, such as the trichomonads, produce large amounts of acetate by an acetate:succinate CoA transferase (ASCT)/succinyl CoA synthetase cycle. The notion that mitochondria and hydrogenosomes may have originated from the same alpha-proteobacterial endosymbiont has led us to look for the presence of a similar metabolic pathway in trypanosomatids because these are the earliest-branching mitochondriate eukaryotes and because they also are known to produce acetate. The mechanism of acetate production in these organisms, however, has remained unknown. Four different members of the trypanosomatid family: promastigotes of Leishmania mexicana mexicana, L. infantum and Phytomonas sp., and procyclics of Trypanosoma brucei were analyzed as well as the parasitic helminth Fasciola hepatica. They all use a mitochondrial ASCT for the production of acetate from acetyl CoA. The succinyl CoA that is produced during acetate formation by ASCT is recycled presumably to succinate by a mitochondrial succinyl CoA synthetase, concomitantly producing ATP from ADP. The ASCT of L. mexicana mexicana promastigotes was further characterized after partial purification of the enzyme. It has a high affinity for acetyl CoA (Km 0.26 mM) and a low affinity for succinate (Km 6.9 mM), which shows that significant acetate production can occur only when high mitochondrial succinate concentrations prevail. This study identifies a metabolic pathway common to mitochondria and hydrogenosomes, which strongly supports a common origin for these two organelles.

  7. Evidence of apoptosis in alcoholic cardiomyopathy.

    PubMed

    Fernández-Solà, Joaquim; Fatjó, Francesc; Sacanella, Emilio; Estruch, Ramón; Bosch, Xavier; Urbano-Márquez, Alvaro; Nicolás, José-María

    2006-08-01

    Apoptosis is a mechanism of cell death implicated in the pathogenesis of alcohol-induced organ damage. Experimental studies have suggested alcohol-mediated apoptosis in the cardiac muscle, and there is evidence of skeletal muscle apoptosis in long-term high-dose alcohol consumers. The relation between skeletal and cardiac muscle damage in alcoholism led us to consider the pathogenic role of apoptosis in alcoholic dilated cardiomyopathy. We evaluated apoptosis in the hearts of individuals with long-term alcoholism (n = 19), of those with long-standing hypertension (n = 20), and of those with no known disease as control subjects (n = 7). Alcohol consumption measurement, heart function evaluation, and myocardial immunohistochemical and morphometric analysis were performed. Apoptosis was evaluated with deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end-labeling assay, and BAX and BCL-2 expressions were used to detect induction of and protection from proapoptotic mechanisms, respectively. Hearts from patients with a history of alcoholism showed apoptotic indexes similar to those of organs from hypertensive donors. Subjects with structural heart damage of alcoholic or hypertensive origin showed higher apoptotic indexes in deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end-labeling, BAX, and BCL-2 assays as compared with control subjects (P < .001 for all). Moreover, New York Heart Association class I alcoholic patients displayed higher BAX and BCL-2 expressions as compared with control subjects. We conclude that apoptosis is present to a similar degree in the heart muscle of high-dose alcohol consumers and long-standing hypertensive subjects and is related to structural damage. Proapoptotic mechanisms are activated in alcoholic patients without heart damage.

  8. Acetylation modulates the STAT signaling code.

    PubMed

    Wieczorek, Martin; Ginter, Torsten; Brand, Peter; Heinzel, Thorsten; Krämer, Oliver H

    2012-12-01

    A fascinating question of modern biology is how a limited number of signaling pathways generate biological diversity and crosstalk phenomena in vivo. Well-defined posttranslational modification patterns dictate the functions and interactions of proteins. The signal transducers and activators of transcription (STATs) are physiologically important cytokine-induced transcription factors. They are targeted by a multitude of posttranslational modifications that control and modulate signaling responses and gene expression. Beyond phosphorylation of serine and tyrosine residues, lysine acetylation has recently emerged as a critical modification regulating STAT functions. Interestingly, acetylation can determine STAT signaling codes by various molecular mechanisms, including the modulation of other posttranslational modifications. Here, we provide an overview on the acetylation of STATs and how this protein modification shapes cellular cytokine responses. We summarize recent advances in understanding the impact of STAT acetylation on cell growth, apoptosis, innate immunity, inflammation, and tumorigenesis. Furthermore, we discuss how STAT acetylation can be targeted by small molecules and we consider the possibility that additional molecules controlling STAT signaling are regulated by acetylation. Our review also summarizes evolutionary aspects and we show similarities between the acetylation-dependent control of STATs and other important molecules. We propose the concept that, similar to the 'histone code', distinct posttranslational modifications and their crosstalk orchestrate the functions and interactions of STAT proteins. PMID:22795479

  9. O-Acetyl Oximes as Transformable Directing Groups for Pd-Catalyzed C–H Bond Functionalization

    PubMed Central

    Neufeldt, Sharon R.; Sanford, Melanie S.

    2010-01-01

    O-Acetyl oximes serve as effective directing groups for Pd-catalyzed sp2 and sp3 C–H functionalization reactions. The C–H functionalization products can be subsequently transformed into ortho- or β-functionalized ketones, alcohols, amines, and heterocycles. PMID:20041702

  10. Akt-dependent metabolic reprogramming regulates tumor cell histone acetylation

    PubMed Central

    Snyder, Nathaniel W.; Wei, Shuanzeng; Venneti, Sriram; Worth, Andrew J.; Yuan, Zuo-Fei; Lim, Hee-Woong; Liu, Shichong; Jackson, Ellen; Aiello, Nicole M.; Haas, Naomi B.; Rebbeck, Timothy R.; Judkins, Alexander; Won, Kyoung-Jae; Chodosh, Lewis A.; Garcia, Benjamin A.; Stanger, Ben Z.; Feldman, Michael D.; Blair, Ian A.; Wellen, Kathryn E.

    2014-01-01

    SUMMARY Histone acetylation plays important roles in gene regulation, DNA replication, and the response to DNA damage, and it is frequently deregulated in tumors. We postulated that tumor cell histone acetylation levels are determined in part by changes in acetyl-CoA availability mediated by oncogenic metabolic reprogramming. Here, we demonstrate that acetyl-CoA is dynamically regulated by glucose availability in cancer cells and that the ratio of acetyl-CoA: coenzyme A within the nucleus modulates global histone acetylation levels. In vivo, expression of oncogenic Kras or Akt stimulates histone acetylation changes that precede tumor development. Furthermore, we show that Akt's effects on histone acetylation are mediated through the metabolic enzyme ATP-citrate lyase (ACLY), and that pAkt(Ser473) levels correlate significantly with histone acetylation marks in human gliomas and prostate tumors. The data implicate acetyl-CoA metabolism as a key determinant of histone acetylation levels in cancer cells. PMID:24998913

  11. Differentiation Between Intracellular and Cell Surface Glycosyl Transferases: Galactosyl Transferase Activity in Intact Cells and in Cell Homogenate

    PubMed Central

    Deppert, Wolfgang; Werchau, Hermann; Walter, Gernot

    1974-01-01

    Intact BHK (baby hamster kidney) cells catalyze the hydrolysis of UDP-galactose to free galactose. The generation of galactose from UDP-galactose and its intracellular utilization impede the detection of possible galactosyl transferases on the cell surface of intact cells. Several independent procedures have been used to distinguish between intracellular and cell surface glycosyl transferases. With these procedures, no evidence was obtained for the presence of detectable amounts of galactosyl transferase activity on the surface of BHK cells. The data suggest that galactosyl transferases do not play a general role in the phenomena of cell adhesion and contact inhibition. PMID:4528509

  12. Acetylator phenotypes in Papua New Guinea

    PubMed Central

    Penketh, R J A; Gibney, S F A; Nurse, G T; Hopkinson, D A

    1983-01-01

    Acetylator phenotypes have been determined in 139 unrelated subjects from the hitherto untested populations of Papua New Guinea, and their relevance to current antituberculous isoniazid chemotherapy is discussed. PMID:6842533

  13. Histone deacetylase 3 indirectly modulates tubulin acetylation.

    PubMed

    Bacon, Travis; Seiler, Caroline; Wolny, Marcin; Hughes, Ruth; Watson, Peter; Schwabe, John; Grigg, Ronald; Peckham, Michelle

    2015-12-15

    Histone deacetylase 3 (HDAC3), a member of the Class I subfamily of HDACs, is found in both the nucleus and the cytoplasm. Its roles in the nucleus have been well characterized, but its cytoplasmic roles are still not elucidated fully. We found that blocking HDAC3 activity using MI192, a compound specific for HDAC3, modulated tubulin acetylation in the human prostate cancer cell line PC3. A brief 1 h treatment of PC3 cells with MI192 significantly increased levels of tubulin acetylation and ablated the dynamic behaviour of microtubules in live cells. siRNA-mediated knockdown (KD) of HDAC3 in PC3 cells, significantly increased levels of tubulin acetylation, and overexpression reduced it. However, the active HDAC3-silencing mediator of retinoic and thyroid receptors (SMRT)-deacetylase-activating domain (DAD) complex did not directly deacetylate tubulin in vitro. These data suggest that HDAC3 indirectly modulates tubulin acetylation.

  14. Qualitative Differences in the N-Acetyl-D-galactosaminyltransferases Produced by Human A1 and A2 Genes

    PubMed Central

    Schachter, H.; Michaels, M. A.; Tilley, Christine A.; Crookston, Marie C.; Crookston, J. H.

    1973-01-01

    This study describes the kinetic properties of N-acetyl-D-galactosaminyltransferase in serum from subjects with blood groups A1 and A2. When the A1 and A2 enzymes were compared, with lacto-N-fucopentaose I and 2′-fucosyllactose as acceptors, the enzymes differed in their cation requirements, pH optima, and Km values. The two acceptors competed for the same transferase. Mixing experiments showed that the lower activity of the A2 enzyme could not be attributed to a modifier or inhibitor in serum. It was concluded that the A1 and A2 enzymes differ qualitatively. PMID:4509655

  15. Levels of histone acetylation in thyroid tumors.

    PubMed

    Puppin, Cinzia; Passon, Nadia; Lavarone, Elisa; Di Loreto, Carla; Frasca, Francesco; Vella, Veronica; Vigneri, Riccardo; Damante, Giuseppe

    2011-08-12

    Histone acetylation is a major mechanism to regulate gene transcription. This post-translational modification is modified in cancer cells. In various tumor types the levels of acetylation at several histone residues are associated to clinical aggressiveness. By using immunohistochemistry we show that acetylated levels of lysines at positions 9-14 of H3 histone (H3K9-K14ac) are significantly higher in follicular adenomas (FA), papillary thyroid carcinomas (PTC), follicular thyroid carcinomas (FTC) and undifferentiated carcinomas (UC) than in normal tissues (NT). Similar data have been obtained when acetylated levels of lysine 18 of H3 histone (H3K18ac) were evaluated. In this case, however, no difference was observed between NT and UC. When acetylated levels of lysine 12 of H4 histone (H4K12ac) were evaluated, only FA showed significantly higher levels in comparison with NT. These data indicate that modification histone acetylation is an early event along thyroid tumor progression and that H3K18 acetylation is switched off in the transition between differentiated and undifferentiated thyroid tumors. By using rat thyroid cell lines that are stably transfected with doxycyclin-inducible oncogenes, we show that the oncoproteins RET-PTC, RAS and BRAF increase levels of H3K9-K14ac and H3K18ac. In the non-tumorigenic rat thyroid cell line FRTL-5, TSH increases levels of H3K18ac. However, this hormone decreases levels of H3K9-K14ac and H4K12ac. In conclusion, our data indicate that neoplastic transformation and hormonal stimulation can modify levels of histone acetylation in thyroid cells. PMID:21763277

  16. Acetyl-L-carnitine increases mitochondrial protein acetylation in the aged rat heart.

    PubMed

    Kerner, Janos; Yohannes, Elizabeth; Lee, Kwangwon; Virmani, Ashraf; Koverech, Aleardo; Cavazza, Claudio; Chance, Mark R; Hoppel, Charles

    2015-01-01

    Previously we showed that in vivo treatment of elderly Fisher 344 rats with acetylcarnitine abolished the age-associated defect in respiratory chain complex III in interfibrillar mitochondria and improved the functional recovery of the ischemic/reperfused heart. Herein, we explored mitochondrial protein acetylation as a possible mechanism for acetylcarnitine's effect. In vivo treatment of elderly rats with acetylcarnitine restored cardiac acetylcarnitine content and increased mitochondrial protein lysine acetylation and increased the number of lysine-acetylated proteins in cardiac subsarcolemmal and interfibrillar mitochondria. Enzymes of the tricarboxylic acid cycle, mitochondrial β-oxidation, and ATP synthase of the respiratory chain showed the greatest acetylation. Acetylation of isocitrate dehydrogenase, long-chain acyl-CoA dehydrogenase, complex V, and aspartate aminotransferase was accompanied by decreased catalytic activity. Several proteins were found to be acetylated only after treatment with acetylcarnitine, suggesting that exogenous acetylcarnitine served as the acetyl-donor. Two-dimensional fluorescence difference gel electrophoresis analysis revealed that acetylcarnitine treatment also induced changes in mitochondrial protein amount; a two-fold or greater increase/decrease in abundance was observed for thirty one proteins. Collectively, our data provide evidence for the first time that in the aged rat heart in vivo administration of acetylcarnitine provides acetyl groups for protein acetylation and affects the amount of mitochondrial proteins. PMID:25660059

  17. Acetylation Reader Proteins: Linking Acetylation Signaling to Genome Maintenance and Cancer

    PubMed Central

    Miller, Kyle M.

    2016-01-01

    Chromatin-based DNA damage response (DDR) pathways are fundamental for preventing genome and epigenome instability, which are prevalent in cancer. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) catalyze the addition and removal of acetyl groups on lysine residues, a post-translational modification important for the DDR. Acetylation can alter chromatin structure as well as function by providing binding signals for reader proteins containing acetyl-lysine recognition domains, including the bromodomain (BRD). Acetylation dynamics occur upon DNA damage in part to regulate chromatin and BRD protein interactions that mediate key DDR activities. In cancer, DDR and acetylation pathways are often mutated or abnormally expressed. DNA damaging agents and drugs targeting epigenetic regulators, including HATs, HDACs, and BRD proteins, are used or are being developed to treat cancer. Here, we discuss how histone acetylation pathways, with a focus on acetylation reader proteins, promote genome stability and the DDR. We analyze how acetylation signaling impacts the DDR in the context of cancer and its treatments. Understanding the relationship between epigenetic regulators, the DDR, and chromatin is integral for obtaining a mechanistic understanding of genome and epigenome maintenance pathways, information that can be leveraged for targeting acetylation signaling, and/or the DDR to treat diseases, including cancer. PMID:27631103

  18. Acetylation Reader Proteins: Linking Acetylation Signaling to Genome Maintenance and Cancer.

    PubMed

    Gong, Fade; Chiu, Li-Ya; Miller, Kyle M

    2016-09-01

    Chromatin-based DNA damage response (DDR) pathways are fundamental for preventing genome and epigenome instability, which are prevalent in cancer. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) catalyze the addition and removal of acetyl groups on lysine residues, a post-translational modification important for the DDR. Acetylation can alter chromatin structure as well as function by providing binding signals for reader proteins containing acetyl-lysine recognition domains, including the bromodomain (BRD). Acetylation dynamics occur upon DNA damage in part to regulate chromatin and BRD protein interactions that mediate key DDR activities. In cancer, DDR and acetylation pathways are often mutated or abnormally expressed. DNA damaging agents and drugs targeting epigenetic regulators, including HATs, HDACs, and BRD proteins, are used or are being developed to treat cancer. Here, we discuss how histone acetylation pathways, with a focus on acetylation reader proteins, promote genome stability and the DDR. We analyze how acetylation signaling impacts the DDR in the context of cancer and its treatments. Understanding the relationship between epigenetic regulators, the DDR, and chromatin is integral for obtaining a mechanistic understanding of genome and epigenome maintenance pathways, information that can be leveraged for targeting acetylation signaling, and/or the DDR to treat diseases, including cancer.

  19. Histone acetylation and globin gene switching.

    PubMed Central

    Hebbes, T R; Thorne, A W; Clayton, A L; Crane-Robinson, C

    1992-01-01

    An affinity-purified antibody that recognises the epitope epsilon-acetyl lysine has been used to fractionate chicken erythrocyte mononucleosomes obtained from 5 and 15 day embryos. The antibody bound chromatin was enriched in multiply acetylated forms of the core histones H3, H4 and H2B, but not in ubiquitinated H2A. The DNA of these modified nucleosomes was probed with genomic sequences from the embryonic beta rho gene (active at 5 days) and from the adult beta A gene (active at 15 days). Both genes were found to be highly enriched in the acetylated nucleosomes fractionated from both 5 day and from 15 day erythrocytes. We conclude that globin switching is not linked to a change in acetylation status of the genes and that a 'poised' gene carries histones acetylated to a similar level as a transcriptionally active gene. Core histone acetylation is not therefore a direct consequence of the transcriptional process and might operate at the level of the globin locus as a general enabling step for transcription. Images PMID:1549462

  20. Protein acetylation in metabolism - metabolites and cofactors.

    PubMed

    Menzies, Keir J; Zhang, Hongbo; Katsyuba, Elena; Auwerx, Johan

    2016-01-01

    Reversible acetylation was initially described as an epigenetic mechanism regulating DNA accessibility. Since then, this process has emerged as a controller of histone and nonhistone acetylation that integrates key physiological processes such as metabolism, circadian rhythm and cell cycle, along with gene regulation in various organisms. The widespread and reversible nature of acetylation also revitalized interest in the mechanisms that regulate lysine acetyltransferases (KATs) and deacetylases (KDACs) in health and disease. Changes in protein or histone acetylation are especially relevant for many common diseases including obesity, diabetes mellitus, neurodegenerative diseases and cancer, as well as for some rare diseases such as mitochondrial diseases and lipodystrophies. In this Review, we examine the role of reversible acetylation in metabolic control and how changes in levels of metabolites or cofactors, including nicotinamide adenine dinucleotide, nicotinamide, coenzyme A, acetyl coenzyme A, zinc and butyrate and/or β-hydroxybutyrate, directly alter KAT or KDAC activity to link energy status to adaptive cellular and organismal homeostasis. PMID:26503676

  1. Nomenclature for mammalian soluble glutathione transferases.

    PubMed

    Mannervik, Bengt; Board, Philip G; Hayes, John D; Listowsky, Irving; Pearson, William R

    2005-01-01

    The nomenclature for human soluble glutathione transferases (GSTs) is extended to include new members of the GST superfamily that have been discovered, sequenced, and shown to be expressed. The GST nomenclature is based on primary structure similarities and the division of GSTs into classes of more closely related sequences. The classes are designated by the names of the Greek letters: Alpha, Mu, Pi, etc., abbreviated in Roman capitals: A, M, P, and so on. (The Greek characters should not be used.) Class members are distinguished by Arabic numerals and the native dimeric protein structures are named according to their subunit composition (e.g., GST A1-2 is the enzyme composed of subunits 1 and 2 in the Alpha class). Soluble GSTs from other mammalian species can be classified in the same manner as the human enzymes, and this chapter presents the application of the nomenclature to the rat and mouse GSTs. PMID:16399376

  2. Nomenclature for mammalian soluble glutathione transferases.

    PubMed

    Mannervik, Bengt; Board, Philip G; Hayes, John D; Listowsky, Irving; Pearson, William R

    2005-01-01

    The nomenclature for human soluble glutathione transferases (GSTs) is extended to include new members of the GST superfamily that have been discovered, sequenced, and shown to be expressed. The GST nomenclature is based on primary structure similarities and the division of GSTs into classes of more closely related sequences. The classes are designated by the names of the Greek letters: Alpha, Mu, Pi, etc., abbreviated in Roman capitals: A, M, P, and so on. (The Greek characters should not be used.) Class members are distinguished by Arabic numerals and the native dimeric protein structures are named according to their subunit composition (e.g., GST A1-2 is the enzyme composed of subunits 1 and 2 in the Alpha class). Soluble GSTs from other mammalian species can be classified in the same manner as the human enzymes, and this chapter presents the application of the nomenclature to the rat and mouse GSTs.

  3. Metabolism of Monoterpenes: Acetylation of (-)-Menthol by a Soluble Enzyme Preparation from Peppermint (Mentha piperita) Leaves.

    PubMed

    Croteau, R; Hooper, C L

    1978-05-01

    The essential oil from mature leaves of flowering peppermint (Mentha piperita L.) contains up to 15% (-)-menthyl acetate, and leaf discs converted exogenous (-)-[G-(3)H]menthol into this ester in approximately 15% yield of the incorporated precursor. Leaf extracts catalyzed the acetyl coenzyme A-dependent acetylation of (-)-[G-(3)H]menthol and the product of this transacetylase reaction was identified by radiochromatographic techniques. Transacetylase activity was located mainly in the 100,000g supernatant fraction, and the preparation was partially purified by combination of Sephadex G-100 gel filtration and chromatography on O-diethylaminoethyl-cellulose. The transacetylase had a molecular weight of about 37,000 as judged by Sephadex G-150 gel filtration, and a pH optimum near 9. The apparent K(m) and velocity for (-)-menthol were 0.3 mm and 16 nmol/hr. mg of protein, respectively. The saturation curve for acetyl coenzyme A was sigmoidal, showing apparent saturation near 0.1 mm. Dithioerythritol was required for maximum activity and stability of the enzyme, and the enzyme was inhibited by thiol directed reagents such as p-hydroxymercuribenzoate. Diisopropylfluorophosphate also inhibited transacylation suggesting the involvement of a serine residue in catalysis. The transacylase was highly specific for acetyl coenzyme A; propionyl coenzyme A and butyryl coenzyme A were not nearly as efficient as acyl donors (11% and 2%, respectively). However, the enzyme was much less selective with regard to the alcohol substrate, suggesting that the nature of the acetate ester synthesized in mint is more dependent on the type of alcohol available than on the specificity of the transacetylase. This is the first report on an enzyme involved in monoterpenol acetylation in plants. A very similar enzyme, catalyzing this key reaction in the metabolism of menthol, was also isolated from the flowers of peppermint. PMID:16660375

  4. Myths about drinking alcohol

    MedlinePlus

    ... to. I spend a lot of time getting alcohol, drinking alcohol, or recovering from the effects of alcohol. ... Institute on Alcohol Abuse and Alcoholism. Overview of Alcohol Consumption. www.niaaa.nih.gov/alcohol-health/overview-alcohol- ...

  5. Glutathione transferase gene family from the housefly Musca domestica.

    PubMed

    Syvanen, M; Zhou, Z H; Wang, J Y

    1994-10-17

    Three new glutathione transferase (GST) genes from the housefly Musca domestica are described. These genes, identified as MdGST-2, -3, and -4, were from cDNA clones obtained from a cDNA bank in phage lambda. The bank was prepared using poly(A)+ RNA from a housefly that is highly resistant to organophosphate insecticides because of enhanced expression of multiple members of the glutathione transferase gene family. The DNA sequence of each is reported and has a complete open reading frame that specified an amino acid sequence similar to other dipteran glutathione transferases. Based on phylogenetic analysis, we can conclude that the insect glutathione transferase gene family falls into two groups, each of which evolves at a different rate, presumably due to differences in functional constraints. We show that MdGST-1 (and their homologues from Drosophila and Lucilia) evolve at a significantly slower rate than the other members of the gene family. Each housefly GST cDNA was inserted into a bacterial plasmid expression system and a glutathione transferase activity was expressed in Escherichia coli. The transcription pattern of each of these glutathione transferases was examined in a variety of different housefly strains that are known to differ in their resistance to organophosphate insecticides due to different patterns of glutathione transferase expression. We found that the level of transcription for two of our clones was positively correlated with the level of organophosphate resistance.

  6. Structural, Kinetic and Proteomic Characterization of Acetyl Phosphate-Dependent Bacterial Protein Acetylation

    PubMed Central

    Sahu, Alexandria; Sorensen, Dylan; Minasov, George; Lima, Bruno P.; Scholle, Michael; Mrksich, Milan; Anderson, Wayne F.; Gibson, Bradford W.; Schilling, Birgit; Wolfe, Alan J.

    2014-01-01

    The emerging view of Nε-lysine acetylation in eukaryotes is of a relatively abundant post-translational modification (PTM) that has a major impact on the function, structure, stability and/or location of thousands of proteins involved in diverse cellular processes. This PTM is typically considered to arise by the donation of the acetyl group from acetyl-coenzyme A (acCoA) to the ε-amino group of a lysine residue that is reversibly catalyzed by lysine acetyltransferases and deacetylases. Here, we provide genetic, mass spectrometric, biochemical and structural evidence that Nε-lysine acetylation is an equally abundant and important PTM in bacteria. Applying a recently developed, label-free and global mass spectrometric approach to an isogenic set of mutants, we detected acetylation of thousands of lysine residues on hundreds of Escherichia coli proteins that participate in diverse and often essential cellular processes, including translation, transcription and central metabolism. Many of these acetylations were regulated in an acetyl phosphate (acP)-dependent manner, providing compelling evidence for a recently reported mechanism of bacterial Nε-lysine acetylation. These mass spectrometric data, coupled with observations made by crystallography, biochemistry, and additional mass spectrometry showed that this acP-dependent acetylation is both non-enzymatic and specific, with specificity determined by the accessibility, reactivity and three-dimensional microenvironment of the target lysine. Crystallographic evidence shows acP can bind to proteins in active sites and cofactor binding sites, but also potentially anywhere molecules with a phosphate moiety could bind. Finally, we provide evidence that acP-dependent acetylation can impact the function of critical enzymes, including glyceraldehyde-3-phosphate dehydrogenase, triosephosphate isomerase, and RNA polymerase. PMID:24756028

  7. Proteomic analysis of acetylation in thermophilic Geobacillus kaustophilus.

    PubMed

    Lee, Dong-Woo; Kim, Dooil; Lee, Yong-Jik; Kim, Jung-Ae; Choi, Ji Young; Kang, Sunghyun; Pan, Jae-Gu

    2013-08-01

    Recent analysis of prokaryotic N(ε)-lysine-acetylated proteins highlights the posttranslational regulation of a broad spectrum of cellular proteins. However, the exact role of acetylation remains unclear due to a lack of acetylated proteome data in prokaryotes. Here, we present the N(ε)-lysine-acetylated proteome of gram-positive thermophilic Geobacillus kaustophilus. Affinity enrichment using acetyl-lysine-specific antibodies followed by LC-MS/MS analysis revealed 253 acetylated peptides representing 114 proteins. These acetylated proteins include not only common orthologs from mesophilic Bacillus counterparts, but also unique G. kaustophilus proteins, indicating that lysine acetylation is pronounced in thermophilic bacteria. These data complement current knowledge of the bacterial acetylproteome and provide an expanded platform for better understanding of the function of acetylation in cellular metabolism.

  8. Alcohol and Alcoholism.

    ERIC Educational Resources Information Center

    National Inst. of Mental Health (DHEW), Chevy Chase, MD. National Clearinghouse for Mental Health Information.

    This concise survey presents some of the highlights of modern research on drinking and alcoholism, as based on technical articles published in the scientific literature and the views expressed by leading authorities in the field. Contents include discussions about: (1) the nature and scope of the problem; (2) the chemical composition of alcoholic…

  9. The Genetic Architecture of Murine Glutathione Transferases

    PubMed Central

    Lu, Lu; Pandey, Ashutosh K.; Houseal, M. Trevor; Mulligan, Megan K.

    2016-01-01

    Glutathione S-transferase (GST) genes play a protective role against oxidative stress and may influence disease risk and drug pharmacokinetics. In this study, massive multiscalar trait profiling across a large population of mice derived from a cross between C57BL/6J (B6) and DBA2/J (D2)—the BXD family—was combined with linkage and bioinformatic analyses to characterize mechanisms controlling GST expression and to identify downstream consequences of this variation. Similar to humans, mice show a wide range in expression of GST family members. Variation in the expression of Gsta4, Gstt2, Gstz1, Gsto1, and Mgst3 is modulated by local expression QTLs (eQTLs) in several tissues. Higher expression of Gsto1 in brain and liver of BXD strains is strongly associated (P < 0.01) with inheritance of the B6 parental allele whereas higher expression of Gsta4 and Mgst3 in brain and liver, and Gstt2 and Gstz1 in brain is strongly associated with inheritance of the D2 parental allele. Allele-specific assays confirmed that expression of Gsto1, Gsta4, and Mgst3 are modulated by sequence variants within or near each gene locus. We exploited this endogenous variation to identify coexpression networks and downstream targets in mouse and human. Through a combined systems genetics approach, we provide new insight into the biological role of naturally occurring variants in GST genes. PMID:26829228

  10. Hypoxanthine-guanine phosphoribosyl transferase deficiency.

    PubMed

    de Bruyn, C H

    1976-02-29

    In man congential lack of enzyme of the purine salvage system, hypoxanthineguanine phosphoribosyl transferase (HG-PRT E.C. 2.4.2.8), is mostly accompanied by a picture known as the Lesch-Nyhan snydrome. The degree of deficiency may vary from zero to a few percent of normal activity but a correlation between the severity of HG-PRT deficiency and the clinical picture has not been observed, no more than a correlation HG-PRT deficiency and neurological dysfunction. But individuals with undetectable HG-PRT activity but without the Lesch-Nyhan syndrome have been described. Patients with partial HG-PRT defiency have clinically distinctive findings. Sometimes mild neurological abnormalities are observed. Because of marked overproduction of ric acid severe gouty arthritis and renal dysfunction are often encountered in both complete and partial deficiency. There is considerable molecular heterogeneity in HG-PRT deficiency in man. Mutant ebnzymes may exhibit different kinetic and electrophoretic properties, indicating that hterwe might be a mutation on the structural gene coding for HG-PRT. Lack of HG-PRT disturbs purine interconversions profoundly. In addition to an important function of HG-PRT in the uptake of the purine hypoxantine and guanine into the cell, the effective uptake of inosine, guanosine and adenosine also seems to be dependent on HG-PRT...

  11. Promoter Strength Comparisons of Maize Shrunken 1 and Alcohol Dehydrogenase 1 and 2 Promoters in Mono- and Dicotyledonous Species 1

    PubMed Central

    Hauptmann, R. M.; Ashraf, M.; Vasil, V.; Hannah, L. C.; Vasil, I. K.; Ferl, R.

    1988-01-01

    Promoter strengths of two maize alcohol dehydrogenase genes, Adh1 and Adh2, and the maize shrunken-1 gene, Sh1, were evaluated by transient expression in cultured protoplasts of Panicum maximum, Triticum monococcum, and Daucus carota. Promoter elements were ligated in correct and opposite orientations as transcriptional gene fusions to the chloramphenicol acetyl transferase gene containing the nopaline synthase 3′ polyadenylation signal. The relative levels of gene expression were compared to the cauliflower mosaic virus 35S promoter. The full length Adh1 promoter (−1100 to +15) functioned in all species, but at a reduced level in D. carota. An Adh1 promoter deletion from −304 to −1100 did not express at detectable levels in any species nor did the Sh1 promoter construction. The Adh2 promoter (−860 to +90) only expressed in D. carota. The full length Adh1 promoter gave the highest level of CAT expression in the monocot cells but at levels which were approximately 30% compared to the CaMV 35S promoter. This was reduced further in D. carota to approximately 4%. These data suggest that at least some of the regulatory factors responsible for promoter function are somewhat species specific and that these differences should be considered in gene expression studies. Images Fig. 2 PMID:16666422

  12. Alcohol use disorder

    MedlinePlus

    ... Alcohol abuse; Problem drinking; Drinking problem; Alcohol addiction; Alcoholism - alcohol use; Substance use - alcohol ... The National Institute on Alcohol Abuse and Alcoholism ... 1 drink per day Men should not drink more than 2 drinks per day

  13. DddD is a CoA-transferase/lyase producing dimethyl sulfide in the marine environment.

    PubMed

    Alcolombri, Uria; Laurino, Paola; Lara-Astiaso, Pedro; Vardi, Assaf; Tawfik, Dan S

    2014-09-01

    Dimethyl sulfide (DMS) is produced in oceans in vast amounts (>10(7) tons/year) and mediates a wide range of processes from regulating marine life forms to cloud formation. Nonetheless, none of the enzymes that produce DMS from dimethylsulfoniopropionate (DMSP) has been adequately characterized. We describe the expression and purification of DddD from the marine bacterium Marinomonas sp. MWYL1 and its biochemical characterization. We identified DMSP and acetyl-coenzyme A to be DddD's native substrates and Asp602 as the active site residue mediating the CoA-transferase prior to lyase activity. These findings shed light on the biochemical utilization of DMSP in the marine environment.

  14. The substrate promiscuity of a phosphopantetheinyl transferase SchPPT for coenzyme A derivatives and acyl carrier proteins.

    PubMed

    Wang, Yue-Yue; Luo, Hong-Dou; Zhang, Xiao-Sheng; Lin, Tao; Jiang, Hui; Li, Yong-Quan

    2016-03-01

    Phosphopantetheinyl transferases (PPTases) catalyze the posttranslational modification of acyl carrier proteins (ACPs) in fatty acid synthases (FASs), ACPs in polyketide synthases, and peptidyl carrier proteins (PCPs) in nonribosomal peptide synthetases (NRPSs) in all organisms. Some bacterial PPTases have broad substrate specificities for ACPs/PCPs and/or coenzyme A (CoA)/CoA analogs, facilitating their application in metabolite production in hosts and/or labeling of ACPs/PCPs, respectively. Here, a group II PPTase SchPPT from Streptomyces chattanoogensis L10 was characterized to accept a heterologous ACP and acetyl-CoA. Thus, SchPPT is a promiscuous PPTase and may be used on polyketide production in heterologous bacterial host and labeling of ACPs.

  15. `Up-regulation of histone acetylation induced by social defeat mediates the conditioned rewarding effects of cocaine.

    PubMed

    Montagud-Romero, S; Montesinos, J; Pascual, M; Aguilar, M A; Roger-Sanchez, C; Guerri, C; Miñarro, J; Rodríguez-Arias, M

    2016-10-01

    Social defeat (SD) induces a long-lasting increase in the rewarding effects of psychostimulants measured using the self-administration and conditioned place procedures (CPP). However, little is known about the epigenetic changes induced by social stress and about their role in the increased response to the rewarding effects of psychostimulants. Considering that histone acetylation regulates transcriptional activity and contributes to drug-induced behavioral changes, we addressed the hypothesis that SD induces transcriptional changes by histone modifications associated with the acquisition of place conditioning. After a fourth defeat, H3(K9) acetylation was decreased in the hippocampus, while there was an increase of HAT and a decrease of HDAC levels in the cortex. Three weeks after the last defeat, mice displayed an increase in histone H4(K12) acetylation and an upregulation of histone acetyl transferase (HAT) activity in the hippocampus. In addition, H3(K4)me3, which is closely associated with transcriptional initiation, was also augmented in the hippocampus three weeks after the last defeat. Inhibition of HAT by curcumin (100mg/kg) before each SD blocked the increase in the conditioned reinforcing effects of 1mg/kg of cocaine, while inhibition of HDAC by valproic acid (500mg/kg) before social stress potentiated cocaine-induced CPP. Preference was reinstated when animals received a priming dose of 0.5mg/kg of cocaine, an effect that was absent in untreated defeated mice. These results suggest that the experience of SD induces chromatin remodeling, alters histone acetylation and methylation, and modifies the effects of cocaine on place conditioning. They also point to epigenetic mechanisms as potential avenues leading to new treatments for the long-term effects of social stress on drug addiction.

  16. `Up-regulation of histone acetylation induced by social defeat mediates the conditioned rewarding effects of cocaine.

    PubMed

    Montagud-Romero, S; Montesinos, J; Pascual, M; Aguilar, M A; Roger-Sanchez, C; Guerri, C; Miñarro, J; Rodríguez-Arias, M

    2016-10-01

    Social defeat (SD) induces a long-lasting increase in the rewarding effects of psychostimulants measured using the self-administration and conditioned place procedures (CPP). However, little is known about the epigenetic changes induced by social stress and about their role in the increased response to the rewarding effects of psychostimulants. Considering that histone acetylation regulates transcriptional activity and contributes to drug-induced behavioral changes, we addressed the hypothesis that SD induces transcriptional changes by histone modifications associated with the acquisition of place conditioning. After a fourth defeat, H3(K9) acetylation was decreased in the hippocampus, while there was an increase of HAT and a decrease of HDAC levels in the cortex. Three weeks after the last defeat, mice displayed an increase in histone H4(K12) acetylation and an upregulation of histone acetyl transferase (HAT) activity in the hippocampus. In addition, H3(K4)me3, which is closely associated with transcriptional initiation, was also augmented in the hippocampus three weeks after the last defeat. Inhibition of HAT by curcumin (100mg/kg) before each SD blocked the increase in the conditioned reinforcing effects of 1mg/kg of cocaine, while inhibition of HDAC by valproic acid (500mg/kg) before social stress potentiated cocaine-induced CPP. Preference was reinstated when animals received a priming dose of 0.5mg/kg of cocaine, an effect that was absent in untreated defeated mice. These results suggest that the experience of SD induces chromatin remodeling, alters histone acetylation and methylation, and modifies the effects of cocaine on place conditioning. They also point to epigenetic mechanisms as potential avenues leading to new treatments for the long-term effects of social stress on drug addiction. PMID:27180319

  17. Glutathione transferases in the bioactivation of azathioprine.

    PubMed

    Modén, Olof; Mannervik, Bengt

    2014-01-01

    The prodrug azathioprine is primarily used for maintaining remission in inflammatory bowel disease, but approximately 30% of the patients suffer adverse side effects. The prodrug is activated by glutathione conjugation and release of 6-mercaptopurine, a reaction most efficiently catalyzed by glutathione transferase (GST) A2-2. Among five genotypes of GST A2-2, the variant A2*E has threefold-fourfold higher catalytic efficiency with azathioprine, suggesting that the expression of A2*E could boost 6-mercaptopurine release and adverse side effects in treated patients. Structure-activity studies of the GST A2-2 variants and homologous alpha class GSTs were made to delineate the determinants of high catalytic efficiency compared to other alpha class GSTs. Engineered chimeras identified GST peptide segments of importance, and replacing the corresponding regions in low-activity GSTs by these short segments produced chimeras with higher azathioprine activity. By contrast, H-site mutagenesis led to decreased azathioprine activity when active-site positions 208 and 213 in these favored segments were mutagenized. Alternative substitutions indicated that hydrophobic residues were favored. A pertinent question is whether variant A2*E represents the highest azathioprine activity achievable within the GST structural framework. This issue was addressed by mutagenesis of H-site residues assumed to interact with the substrate based on molecular modeling. The mutants with notably enhanced activities had small or polar residues in the mutated positions. The most active mutant L107G/L108D/F222H displayed a 70-fold enhanced catalytic efficiency with azathioprine. The determination of its structure by X-ray crystallography showed an expanded H-site, suggesting improved accommodation of the transition state for catalysis.

  18. Gene encoding acetyl-coenzyme A carboxylase

    DOEpatents

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

    1996-09-24

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

  19. 21 CFR 172.828 - Acetylated monoglycerides.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... molecular distillation or by steam stripping; or (2) The direct acetylation of edible monoglycerides with acetic anhydride without the use of catalyst or molecular distillation, and with the removal by vacuum distillation, if necessary, of the acetic acid, acetic anhydride, and triacetin. (b) The food additive has...

  20. 21 CFR 172.828 - Acetylated monoglycerides.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... molecular distillation or by steam stripping; or (2) The direct acetylation of edible monoglycerides with acetic anhydride without the use of catalyst or molecular distillation, and with the removal by vacuum distillation, if necessary, of the acetic acid, acetic anhydride, and triacetin. (b) The food additive has...

  1. 21 CFR 172.828 - Acetylated monoglycerides.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... molecular distillation or by steam stripping; or (2) The direct acetylation of edible monoglycerides with acetic anhydride without the use of catalyst or molecular distillation, and with the removal by vacuum distillation, if necessary, of the acetic acid, acetic anhydride, and triacetin. (b) The food additive has...

  2. Gene encoding acetyl-coenzyme A carboxylase

    DOEpatents

    Roessler, Paul G.; Ohlrogge, John B.

    1996-01-01

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

  3. Histone deacetylase 3 indirectly modulates tubulin acetylation

    PubMed Central

    Bacon, Travis; Seiler, Caroline; Wolny, Marcin; Hughes, Ruth; Watson, Peter; Schwabe, John; Grigg, Ronald; Peckham, Michelle

    2015-01-01

    Histone deacetylase 3 (HDAC3), a member of the Class I subfamily of HDACs, is found in both the nucleus and the cytoplasm. Its roles in the nucleus have been well characterized, but its cytoplasmic roles are still not elucidated fully. We found that blocking HDAC3 activity using MI192, a compound specific for HDAC3, modulated tubulin acetylation in the human prostate cancer cell line PC3. A brief 1 h treatment of PC3 cells with MI192 significantly increased levels of tubulin acetylation and ablated the dynamic behaviour of microtubules in live cells. siRNA-mediated knockdown (KD) of HDAC3 in PC3 cells, significantly increased levels of tubulin acetylation, and overexpression reduced it. However, the active HDAC3–silencing mediator of retinoic and thyroid receptors (SMRT)–deacetylase-activating domain (DAD) complex did not directly deacetylate tubulin in vitro. These data suggest that HDAC3 indirectly modulates tubulin acetylation. PMID:26450925

  4. Selective inhibitors of glutathione transferase P1 with trioxane structure as anticancer agents.

    PubMed

    Bräutigam, Maria; Teusch, Nicole; Schenk, Tobias; Sheikh, Miriam; Aricioglu, Rocky Z; Borowski, Swantje H; Neudörfl, Jörg-Martin; Baumann, Ulrich; Griesbeck, Axel G; Pietsch, Markus

    2015-04-01

    The response to chemotherapy in cancer patients is frequently compromised by drug resistance. Although chemoresistance is a multifactorial phenomenon, many studies have demonstrated that altered drug metabolism through the expression of phase II conjugating enzymes, including glutathione transferases (GSTs), in tumor cells can be directly correlated with resistance against a wide range of marketed anticancer drugs. In particular, overexpression of glutathione transferase P1 (GSTP1) appears to be a factor for poor prognosis during cancer therapy. Former and ongoing clinical trials have confirmed GSTP1 inhibition as a principle for antitumor therapy. A new series of 1,2,4-trioxane GSTP1 inhibitors were designed via a type II photooxygenation route of allylic alcohols followed by acid-catalyzed peroxyacetalization with aldehydes. A set of novel inhibitors exhibit low micromolar to high nanomolar inhibition of GSTP1, revealing preliminary SAR for further lead optimization. Importantly, high selectivity over another two human GST classes (GSTA1 and GSTM2) has been achieved. The trioxane GSTP1 inhibitors may therefore serve as a basis for the development of novel drug candidates in overcoming chemoresistance.

  5. Property enhancement of optically transparent bionanofiber composites by acetylation

    NASA Astrophysics Data System (ADS)

    Nogi, Masaya; Abe, Kentaro; Handa, Keishin; Nakatsubo, Fumiaki; Ifuku, Shinsuke; Yano, Hiroyuki

    2006-12-01

    The authors studied acetylation of bacterial cellulose (BC) nanofibers to widen the applications of BC nanocomposites in optoelectronic devices. The slight acetylation of BC nanofibers significantly reduces the hygroscopicity of BC nanocomposites, while maintaining their high optical transparency and thermal stability. Furthermore, the degradation in optical transparency at elevated temperature (200°C) was significantly reduced by acetylation treatment. Therefore, the acetylation of bionanofibers has an extraordinary potential as treatment for property enhancement of bionanofiber composites.

  6. 40 CFR 721.10520 - Acetylated fatty acid glycerides (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acetylated fatty acid glycerides... Specific Chemical Substances § 721.10520 Acetylated fatty acid glycerides (generic). (a) Chemical substance... acetylated fatty acid glycerides (PMN P-11-160) is subject to reporting under this section for...

  7. 40 CFR 721.10520 - Acetylated fatty acid glycerides (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acetylated fatty acid glycerides... Specific Chemical Substances § 721.10520 Acetylated fatty acid glycerides (generic). (a) Chemical substance... acetylated fatty acid glycerides (PMN P-11-160) is subject to reporting under this section for...

  8. The Fusarium oxysporum gnt2, encoding a putative N-acetylglucosamine transferase, is involved in cell wall architecture and virulence.

    PubMed

    López-Fernández, Loida; Ruiz-Roldán, Carmen; Pareja-Jaime, Yolanda; Prieto, Alicia; Khraiwesh, Husam; Roncero, M Isabel G

    2013-01-01

    With the aim to decipher the molecular dialogue and cross talk between Fusarium oxysporum f.sp. lycopersci and its host during infection and to understand the molecular bases that govern fungal pathogenicity, we analysed genes presumably encoding N-acetylglucosaminyl transferases, involved in glycosylation of glycoproteins, glycolipids, proteoglycans or small molecule acceptors in other microorganisms. In silico analysis revealed the existence of seven putative N-glycosyl transferase encoding genes (named gnt) in F. oxysporum f.sp. lycopersici genome. gnt2 deletion mutants showed a dramatic reduction in virulence on both plant and animal hosts. Δgnt2 mutants had αalterations in cell wall properties related to terminal αor β-linked N-acetyl glucosamine. Mutant conidia and germlings also showed differences in structure and physicochemical surface properties. Conidial and hyphal aggregation differed between the mutant and wild type strains, in a pH independent manner. Transmission electron micrographs of germlings showed strong cell-to-cell adherence and the presence of an extracellular chemical matrix. Δgnt2 cell walls presented a significant reduction in N-linked oligosaccharides, suggesting the involvement of Gnt2 in N-glycosylation of cell wall proteins. Gnt2 was localized in Golgi-like sub-cellular compartments as determined by fluorescence microscopy of GFP::Gnt2 fusion protein after treatment with the antibiotic brefeldin A or by staining with fluorescent sphingolipid BODIPY-TR ceramide. Furthermore, density gradient ultracentrifugation allowed co-localization of GFP::Gnt2 fusion protein and Vps10p in subcellular fractions enriched in Golgi specific enzymatic activities. Our results suggest that N-acetylglucosaminyl transferases are key components for cell wall structure and influence interactions of F. oxysporum with both plant and animal hosts during pathogenicity. PMID:24416097

  9. [3H]Indole-3-acetyl-myo-inositol hydrolysis by extracts of Zea mays L. vegetative tissue

    NASA Technical Reports Server (NTRS)

    Hall, P. J.; Bandurski, R. S.

    1986-01-01

    [3H]Indole-3-acetyl-myo-inositol was hydrolyzed by buffered extracts of acetone powders prepared from 4 day shoots of dark grown Zea mays L. seedlings. The hydrolytic activity was proportional to the amount of extract added and was linear for up to 6 hours at 37 degrees C. Boiled or alcohol denatured extracts were inactive. Analysis of reaction mixtures by high performance liquid chromatography demonstrated that not all isomers of indole-3-acetyl-myo-inositol were hydrolyzed at the same rate. Buffered extracts of acetone powders were prepared from coleoptiles and mesocotyls. The rates of hydrolysis observed with coleoptile extracts were greater than those observed with mesocotyl extracts. Active extracts also catalyzed the hydrolysis of esterase substrates such as alpha-naphthyl acetate and the methyl esters of indoleacetic acid and naphthyleneacetic acid. Attempts to purify the indole-3-acetyl-myo-inositol hydrolyzing activity by chromatographic procedures resulted in only slight purification with large losses of activity. Chromatography over hydroxylapatite allowed separation of two enzymically active fractions, one of which catalyzed the hydrolysis of both indole-3-acetyl-myo-inositol and esterase substrates. With the other enzymic hydrolysis of esterase substrates was readily demonstrated, but no hydrolysis of indole-3-acetyl-myo-inositol was ever detected.

  10. Functional analysis of N-linking oligosaccharyl transferase enzymes encoded by deep-sea vent proteobacteria.

    PubMed

    Mills, Dominic C; Jervis, Adrian J; Abouelhadid, Sherif; Yates, Laura E; Cuccui, Jon; Linton, Dennis; Wren, Brendan W

    2016-04-01

    Bacterial N-linking oligosaccharyl transferases (OTase enzymes) transfer lipid-linked glycans to selected proteins in the periplasm and were first described in the intestinal pathogen Campylobacter jejuni, a member of the ε-proteobacteria-subdivision of bacteria. More recently, orthologues from other ε-proteobacterial Campylobacter and Helicobacter species and a δ-proteobacterium, Desulfovibrio desulfuricans, have been described, suggesting that these two subdivisions of bacteria may be a source of further N-linked protein glycosylation systems. Whole-genome sequencing of both ε- and δ-proteobacteria from deep-sea vent habitats, a rich source of species from these subdivisions, revealed putative ORFs encoding OTase enzymes and associated adjacent glycosyltransferases similar to the C. jejuni N-linked glycosylation locus. We expressed putative OTase ORFs from the deep-sea vent species Nitratiruptor tergarcus, Sulfurovum lithotrophicum and Deferribacter desulfuricans in Escherichia coli and showed that they were able to functionally complement the C. jejuni OTase, CjPglB. The enzymes were shown to possess relaxed glycan specificity, transferring diverse glycan structures and demonstrated different glycosylation sequon specificities. Additionally, a permissive D. desulfuricans acceptor protein was identified, and we provide evidence that the N-linked glycan synthesized by N. tergarcus and S. lithotrophicum contains an acetylated sugar at the reducing end. This work demonstrates that deep-sea vent bacteria encode functional N-glycosylation machineries and are a potential source of biotechnologically important OTase enzymes. PMID:26610891

  11. Functional analysis of N-linking oligosaccharyl transferase enzymes encoded by deep-sea vent proteobacteria

    PubMed Central

    Mills, Dominic C.; Jervis, Adrian J.; Abouelhadid, Sherif; Yates, Laura E.; Cuccui, Jon; Linton, Dennis; Wren, Brendan W.

    2016-01-01

    Bacterial N-linking oligosaccharyl transferases (OTase enzymes) transfer lipid-linked glycans to selected proteins in the periplasm and were first described in the intestinal pathogen Campylobacter jejuni, a member of the ε-proteobacteria-subdivision of bacteria. More recently, orthologues from other ε-proteobacterial Campylobacter and Helicobacter species and a δ-proteobacterium, Desulfovibrio desulfuricans, have been described, suggesting that these two subdivisions of bacteria may be a source of further N-linked protein glycosylation systems. Whole-genome sequencing of both ε- and δ-proteobacteria from deep-sea vent habitats, a rich source of species from these subdivisions, revealed putative ORFs encoding OTase enzymes and associated adjacent glycosyltransferases similar to the C. jejuni N-linked glycosylation locus. We expressed putative OTase ORFs from the deep-sea vent species Nitratiruptor tergarcus, Sulfurovum lithotrophicum and Deferribacter desulfuricans in Escherichia coli and showed they were able to functionally complement the C. jejuni OTase, CjPglB . The enzymes were shown to possess relaxed glycan specificity, transferring diverse glycan structures and demonstrated different glycosylation sequon specificities. Additionally a permissive D. desulfuricans acceptor protein was identified, and we provide evidence that the N-linked glycan synthesised by N. tergarcus and S. lithotrophicum contains an acetylated sugar at the reducing end. This work demonstrates that deep-sea vent bacteria encode functional N-glycosylation machineries and are a potential source of biotechnologically important OTase enzymes. PMID:26610891

  12. Acamprosate and alcohol: II. Effects on alcohol withdrawal in the rat.

    PubMed

    Spanagel, R; Putzke, J; Stefferl, A; Schöbitz, B; Zieglgänsberger, W

    1996-06-01

    The suppressing effect of acamprosate (calcium-acetyl homotaurinate) on alcohol drinking is well established; however, little is known about its effects upon the alcohol-induced withdrawal syndrome. Male Wistar rats received as a sole drinking fluid a 20% (v/v) alcohol solution for one week. Animals consumed on average 5.3 +/- 0.3 g/kg per day alcohol, which resulted in blood alcohol levels of 38 +/- 14 mg/dl. For the quantification of alcohol withdrawal we used a new radio-telemetric system which enabled us to monitor body temperature, locomotor activity, food and water intake patterns constantly during alcohol withdrawal. Although alcohol intake and the resulting blood alcohol levels were low, clear signs of withdrawal could be observed. Thus, hyperthermia and hyperlocomotion occurred 18 h after the termination of forced alcohol drinking. Food intake was initially enhanced but dropped significantly below basal food intake in control animals one day after the termination of forced alcohol drinking. Acamprosate given twice a day (200 mg/kg, i.p., 8 a.m. and 8 p.m.) reduced hyperlocomotion and food intake significantly in the alcohol withdrawal animals, however, it did not change withdrawal-induced hyperthermia. When acamprosate was given to alcohol-naive animals, it increased locomotor activity and body temperature transiently, in particular during the rats' active night phase. In summary, (i) the radio-telemetric system used in the present study proved to be a very sensitive method for quantifying alcohol-induced withdrawal symptoms; (ii) acamprosate reduced alcohol-induced physical signs of withdrawal, however, this effect could not be observed for all parameters measured, which might be explained by the fact that (iii) acamprosate exerts a slight, transient psychomotor stimulant effects by itself.

  13. Acetylation and characterization of banana (Musa paradisiaca) starch.

    PubMed

    Bello-Pérez, L A; Contreras-Ramos, S M; Jìmenez-Aparicio, A; Paredes-López, O

    2000-01-01

    Banana native starch was acetylated and some of its functional properties were evaluated and compared to corn starch. In general, acetylated banana starch presented higher values in ash, protein and fat than corn acetylated starch. The modified starches had minor tendency to retrogradation assessed as % transmittance of starch pastes. At high temperature acetylated starches presented a water retention capacity similar to their native counterpart. The acetylation considerably increased the solubility of starches, and a similar behavior was found for swelling power. When freeze-thaw stability was studied, acetyl banana starch drained approximately 60% of water in the first and second cycles, but in the third and fourth cycles the percentage of separated water was low. However, acetyl corn starch showed lower freeze-thaw stability than the untreated sample. The modification increased the viscosity of banana starch pastes.

  14. Dynamic Protein Acetylation in Plant–Pathogen Interactions

    PubMed Central

    Song, Gaoyuan; Walley, Justin W.

    2016-01-01

    Pathogen infection triggers complex molecular perturbations within host cells that results in either resistance or susceptibility. Protein acetylation is an emerging biochemical modification that appears to play central roles during host–pathogen interactions. To date, research in this area has focused on two main themes linking protein acetylation to plant immune signaling. Firstly, it has been established that proper gene expression during defense responses requires modulation of histone acetylation within target gene promoter regions. Second, some pathogens can deliver effector molecules that encode acetyltransferases directly within the host cell to modify acetylation of specific host proteins. Collectively these findings suggest that the acetylation level for a range of host proteins may be modulated to alter the outcome of pathogen infection. This review will focus on summarizing our current understanding of the roles of protein acetylation in plant defense and highlight the utility of proteomics approaches to uncover the complete repertoire of acetylation changes triggered by pathogen infection. PMID:27066055

  15. Overview of Alcohol Consumption

    MedlinePlus

    ... Search Alcohol & Your Health Overview of Alcohol Consumption Alcohol's Effects on the Body Alcohol Use Disorder Fetal Alcohol ... other questions about alcohol. Here’s what we know: Alcohol’s effects vary from person to person, depending on a ...

  16. Alcohol and pregnancy

    MedlinePlus

    Drinking alcohol during pregnancy; Fetal alcohol syndrome - pregnancy; FAS - fetal alcohol syndrome ... When a pregnant woman drinks alcohol, the alcohol travels through her blood and into the baby's blood, tissues, and organs. Alcohol breaks down much more slowly in ...

  17. Thioltransferase activity of bovine lens glutathione S-transferase.

    PubMed Central

    Dal Monte, M; Cecconi, I; Buono, F; Vilardo, P G; Del Corso, A; Mura, U

    1998-01-01

    A Mu-class glutathione S-transferase purified to electrophoretic homogeneity from bovine lens displayed thioltransferase activity, catalysing the transthiolation reaction between GSH and hydroxyethyldisulphide. The thiol-transfer reaction is composed of two steps, the formation of GSSG occurring through the generation of an intermediate mixed disulphide between GSH and the target disulphide. Unlike glutaredoxin, which is only able to catalyse the second step of the transthiolation process, glutathioneS-transferase catalyses both steps of the reaction. Data are presented showing that bovine lens glutathione S-transferase and rat liver glutaredoxin, which was used as a thioltransferase enzyme model, can operate in synergy to catalyse the GSH-dependent reduction of hydroxyethyldisulphide. PMID:9693102

  18. Fragrance material review on acetyl cedrene.

    PubMed

    Scognamiglio, J; Letizia, C S; Politano, V T; Api, A M

    2013-12-01

    A toxicologic and dermatologic review of acetyl cedrene when used as a fragrance ingredient is presented. Acetyl cedrene is a member of the fragrance structural group Alkyl Cyclic Ketones. The generic formula for this group can be represented as (R1)(R2)CO. These fragrances can be described as being composed of an alkyl, R1, and various substituted and bicyclic saturated or unsaturated cyclic hydrocarbons, R2, in which one of the rings may include up to 12 carbons. Alternatively, R2 may be a carbon bridge of C2-C4 carbon chain length between the ketone and cyclic hydrocarbon. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for acetyl cedrene were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, elicitation, phototoxicity, photoallergy, toxicokinetics, repeated dose, reproductive toxicity, and genotoxicity data. A safety assessment of the entire Alkyl Cyclic Ketones will be published simultaneously with this document; please refer to Belsito et al. (2013) (Belsito, D., Bickers, D., Bruze, M., Calow, P., Dagli, M., Fryer, A.D., Greim, H., Miyachi, Y., Saurat, J.H., Sipes, I.G., 2013. A Toxicologic and Dermatologic Assessment of Alkyl Cyclic Ketones When Used as Fragrance Ingredients. Submitted with this manuscript.) for an overall assessment of the safe use of this material and all Alkyl Cyclic Ketones in fragrances.

  19. Fragrance material review on acetyl carene.

    PubMed

    Scognamiglio, J; Letizia, C S; Api, A M

    2013-12-01

    A toxicologic and dermatologic review of acetyl carene when used as a fragrance ingredient is presented. Acetyl carene is a member of the fragrance structural group Alkyl Cyclic Ketones. These fragrances can be described as being composed of an alkyl, R1, and various substituted and bicyclic saturated or unsaturated cyclic hydrocarbons, R2, in which one of the rings may include up to 12 carbons. Alternatively, R2 may be a carbon bridge of C2-C4 carbon chain length between the ketone and cyclic hydrocarbon. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for acetyl carene were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, and skin sensitization data. A safety assessment of the entire Alkyl Cyclic Ketones will be published simultaneously with this document; please refer to Belsito et al. (Belsito, D., Bickers, D., Bruze, M., Calow, P., Dagli, M., Fryer, A.D., Greim, H., Miyachi, Y., Saurat, J.H., Sipes, I.G., 2013A Toxicologic and dermatologic assessment of alkyl cyclic ketones when used as fragrance ingredients. (submitted for publication).) for an overall assessment of the safe use of this material and all Alkyl Cyclic Ketones in fragrances.

  20. Antibodies specific to acetylated histones document the existence of deposition- and transcription-related histone acetylation in Tetrahymena

    PubMed Central

    1989-01-01

    In this study, we have constructed synthetic peptides which are identical to hyperacetylated amino termini of two Tetrahymena core histones (tetra-acetylated H4 and penta-acetylated hv1) and used them to generate polyclonal antibodies specific for acetylated forms (mono-, di-, tri-, etc.) of these histones. Neither of these antisera recognizes histone that is unacetylated. Immunoblotting analyses demonstrate that both transcription-related and deposition-related acetate groups on H4 are recognized by both antisera. In addition, the antiserum raised against penta-acetylated hv1 also recognizes acetylated forms of this variant. Immunofluorescent analyses with both antisera demonstrate that, as expected, histone acetylation is specific to macronuclei (or new macronuclei) at all stages of the life cycle except when micronuclei undergo periods of rapid replication and chromatin assembly. During this time micronuclear staining is also detected. Our results also suggest that transcription-related acetylation begins selectively in new macronuclei immediately after the second postzygotic division. Acetylated histone is not observed in new micronuclei during stages corresponding to anlagen development and, therefore, histone acetylation can be distributed asymmetrically in development. Equally striking is the rapid turnover of acetylated histone in parental macronuclei during the time of their inactivation and elimination from the cell. Taken together, these data lend strong support to the idea that modulation of histone acetylation plays an important role in gene activation and in chromatin assembly. PMID:2654136

  1. Aroylnitrenes with singlet ground states: photochemistry of acetyl-substituted aroyl and aryloxycarbonyl azides

    SciTech Connect

    Sigman, M.E.; Autrey, T.; Schuster, G.B.

    1988-06-22

    The photochemistry of 4-acetylbenzoyl azide (ABA), 4-acetyl-4'-biphenoyl azide (ADA), and 4-acetylphenoxycarbonyl azide (APA) shows unusual wavelength and structural effects. Irradiation of ABA or ADA into their ..pi..-..pi..* bands with deep-UV light leads to formation of 4-acetylbenzoylnitrene (ABN) and 4-acetyl-4'-biphenoylnitrene (ADN), respectively, in competition with photo-Curtius rearrangement to form isocyanates. Irradiation of these azides into their n-..pi..* bands with near-UV light gives only the aroylnitrenes. The triplet excited states of the azides were detected chemically and by transient spectroscopic techniques. Nitrogen loss following near-UV irradiation occurs exclusively from the excited triplet azides. However, the chemical properties of ABN and ADN are consistent only with reactions originating from their singlet states. An ESR spectrum is observed at 8 K for ((4-acetylphenoxy)carbonyl) nitrene (APN) but not for 4-acetylbenzoylnitrene (ABN) or 4-acetyl-4'-biphenylcarbonylnitrene (ADN). The chemical properties of APN in tert-butyl alcohol show that its triplet is no more than 5 kcal/mol below its lowest single state. In contrast, the chemical properties of ABN and ADN indicate that these nitrenes have singlet ground states.

  2. O-Acetylation of Plant Cell Wall Polysaccharides

    PubMed Central

    Gille, Sascha; Pauly, Markus

    2011-01-01

    Plant cell walls are composed of structurally diverse polymers, many of which are O-acetylated. How plants O-acetylate wall polymers and what its function is remained elusive until recently, when two protein families were identified in the model plant Arabidopsis that are involved in the O-acetylation of wall polysaccharides – the reduced wall acetylation (RWA) and the trichome birefringence-like (TBL) proteins. This review discusses the role of these two protein families in polysaccharide O-acetylation and outlines the differences and similarities of polymer acetylation mechanisms in plants, fungi, bacteria, and mammals. Members of the TBL protein family had been shown to impact pathogen resistance, freezing tolerance, and cellulose biosynthesis. The connection of TBLs to polysaccharide O-acetylation thus gives crucial leads into the biological function of wall polymer O-acetylation. From a biotechnological point understanding the O-acetylation mechanism is important as acetyl-substituents inhibit the enzymatic degradation of wall polymers and released acetate can be a potent inhibitor in microbial fermentations, thus impacting the economic viability of, e.g., lignocellulosic based biofuel production. PMID:22639638

  3. Serum gamma glutamyl transferase as a specific indicator of bile duct lesions in the rat liver.

    PubMed Central

    Leonard, T. B.; Neptun, D. A.; Popp, J. A.

    1984-01-01

    Serum gamma-glutamyl transferase (GGT), a marker of hepatic injury used extensively in humans, has been used rarely in rats because its specificity has not been previously defined. Studies were designed for investigation of the specificity of serum GGT activity with the use of cell type specific hepatotoxicants in Fischer 344 rats. Single necrogenic doses of CCl4, allyl alcohol (AA), and alpha-naphthylisothiocyanate (ANIT) were used to produce cell specific injury in centrilobular hepatocytes, periportal hepatocytes, and bile duct cells, respectively. Administration of CCl4 markedly increased serum activities of alanine aminotransferase (ALT), alkaline phosphatase (AP), and serum bile acid concentrations within 24 hours but had no effect on serum GGT activity. ANIT treatment increased serum GGT and AP activities and bile acid concentration 24 hours following administration. Allyl alcohol administration increased serum ALT activity but had no effect on GGT activity. Administration of ANIT in the diet at 0.01%, 0.022%, 0.047%, and 0.1% for 2, 4, and 6 weeks produced dose- and time-dependent increases in serum GGT activity which strongly correlated with quantitative increases in hepatic bile duct volume, which was determined morphometrically. These observations support the use of serum GGT activity in the rat as diagnostic of bile duct cell necrosis when increases are detected shortly after the insult and as an indicator of possible bile duct hyperplasia. Images Figure 1 Figure 3 PMID:6147091

  4. Serum gamma glutamyl transferase as a specific indicator of bile duct lesions in the rat liver.

    PubMed

    Leonard, T B; Neptun, D A; Popp, J A

    1984-08-01

    Serum gamma-glutamyl transferase (GGT), a marker of hepatic injury used extensively in humans, has been used rarely in rats because its specificity has not been previously defined. Studies were designed for investigation of the specificity of serum GGT activity with the use of cell type specific hepatotoxicants in Fischer 344 rats. Single necrogenic doses of CCl4, allyl alcohol (AA), and alpha-naphthylisothiocyanate (ANIT) were used to produce cell specific injury in centrilobular hepatocytes, periportal hepatocytes, and bile duct cells, respectively. Administration of CCl4 markedly increased serum activities of alanine aminotransferase (ALT), alkaline phosphatase (AP), and serum bile acid concentrations within 24 hours but had no effect on serum GGT activity. ANIT treatment increased serum GGT and AP activities and bile acid concentration 24 hours following administration. Allyl alcohol administration increased serum ALT activity but had no effect on GGT activity. Administration of ANIT in the diet at 0.01%, 0.022%, 0.047%, and 0.1% for 2, 4, and 6 weeks produced dose- and time-dependent increases in serum GGT activity which strongly correlated with quantitative increases in hepatic bile duct volume, which was determined morphometrically. These observations support the use of serum GGT activity in the rat as diagnostic of bile duct cell necrosis when increases are detected shortly after the insult and as an indicator of possible bile duct hyperplasia. PMID:6147091

  5. Rational design of an organometallic glutathione transferase inhibitor

    SciTech Connect

    Ang, W.H.; Parker, L.J.; De Luca, A.; Juillerat-Jeanneret, L.; Morton, C.J.; LoBello, M.; Parker, M.W.; Dyson, P.J.

    2010-08-17

    A hybrid organic-inorganic (organometallic) inhibitor was designed to target glutathione transferases. The metal center is used to direct protein binding, while the organic moiety acts as the active-site inhibitor. The mechanism of inhibition was studied using a range of biophysical and biochemical methods.

  6. Homogentisate solanesyl transferase (HST) cDNA’s in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize white seedling 3 (w3) has served as a model albino-seedling mutant since its discovery in 1923. We show that the w3 phenotype is caused by disruptions in homogentisate solanesyl transferase (HST), an enzyme that catalyzes the committed step in plastoquinone-9 (PQ9) biosynthesis. This reaction ...

  7. 21 CFR 862.1535 - Ornithine carbamyl transferase test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ornithine carbamyl transferase test system. 862.1535 Section 862.1535 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1535 Ornithine...

  8. Histamine N-methyl transferase: inhibition by drugs.

    PubMed Central

    Pacifici, G M; Donatelli, P; Giuliani, L

    1992-01-01

    1. Histamine N-methyl transferase activity was measured in samples of human liver, brain, kidney, lung and intestinal mucosa. The mean (+/- s.d.) rate (nmol min-1 mg-1 protein) of histamine N-methylation was 1.78 +/- 0.59 (liver, n = 60), 1.15 +/- 0.38 (renal cortex, n = 8), 0.79 +/- 0.14 (renal medulla, n = 8), 0.35 +/- 0.08 (lung, n = 20), 0.47 +/- 0.18 (human intestine, n = 30) and 0.29 +/- 0.14 (brain, n = 13). 2. Inhibition of histamine N-methyl transferase by 15 drugs was investigated in human liver. The IC50 for the various drugs ranged over three orders of magnitude; chloroquine was the most potent inhibitor. 3. The average IC50 values for chloroquine were 12.6, 22.0, 19.0, 21.6 microM in liver, renal cortex, brain and colon, respectively. These values are lower than the Michaelis-Menten constant for histamine N-methyltransferase in liver (43.8 microM) and kidney (45.5 microM). Chloroquine carried a mixed non-competitive inhibition of hepatic histamine N-methyl transferase. Some side-effects of chloroquine may be explained by inhibition of histamine N-methyl transferase. PMID:1457266

  9. Preparation, physicochemical characterization and application of acetylated lotus rhizome starches.

    PubMed

    Sun, Suling; Zhang, Ganwei; Ma, Chaoyang

    2016-01-01

    Acetylated lotus rhizome starches were prepared, physicochemically characterized and used as food additives in puddings. The percentage content of the acetyl groups and degree of substitution increased linearly with the amount of acetic anhydride used. The introduction of acetyl groups was confirmed via Fourier transform infrared (FT-IR) spectroscopy. The values of the pasting parameters were lower for acetylated starch than for native starch. Acetylation was found to increase the light transmittance (%), the freeze-thaw stability, the swelling power and the solubility of the starch. Sensorial scores for puddings prepared using native and acetylated lotus rhizome starches as food additives indicated that puddings produced from the modified starches with superior properties over those prepared from native starch. PMID:26453845

  10. 2-Acetyl­pyridinium bromanilate

    PubMed Central

    Thomas, Lynne H.; Boyle, Bryan; Clive, Lesley A.; Collins, Anna; Currie, Lynsey D.; Gogol, Malgorzata; Hastings, Claire; Jones, Andrew O. F.; Kennedy, Jennifer L.; Kerr, Graham B.; Kidd, Alastair; Lawton, Lorreta M.; Macintyre, Susan J.; MacLean, Niall M.; Martin, Alan R. G.; McGonagle, Kate; Melrose, Samantha; Rew, Gaius A.; Robinson, Colin W.; Schmidtmann, Marc; Turnbull, Felicity B.; Williams, Lewis G.; Wiseman, Alan Y.; Wocial, Malgorzata H.; Wilson, Chick C.

    2009-01-01

    In the crystal of the title mol­ecular salt (systematic name: 2-acetyl­pyridinium 2,5-dibromo-4-hydr­oxy-3,6-dioxocyclo­hexa-1,4-dienolate), C7H8NO+·C6HBr2O4 −, centrosymmetric rings consisting of two cations and two anions are formed, with the components linked by alternating O—H⋯O and N—H⋯O hydrogen bonds. Short O⋯Br contacts [3.243 (2) and 3.359 (2) Å] may help to consolidate the packing. PMID:21583087

  11. Survey of the human acetylator polymorphism in spontaneous disorders.

    PubMed Central

    Evans, D A

    1984-01-01

    There is ample evidence that the human acetylator phenotypes are associated with drug induced phenomena. It is principally the slow acetylators who exhibit toxic adverse effects because of their relative inability to detoxify the original drug compounds. In rare instances, however, it is the rapid acetylators who are at a disadvantage. In the matter of association of spontaneous disease with either acetylator phenotype, there are two groups of disorders to consider. First, disorders in which carcinogenic amines are known to be an aetiological factor. This is because these amines are substrates for the polymorphic N-acetyltransferase activity and hence there is a possible rational basis for searching for an association. Secondly, other disorders where searches for associations are based more on hunches. In the first group there is a definite statistical association between cancer of the bladder and the slow acetylator phenotype. In prevalence studies the slow phenotype is 39% more associated with bladder cancer than is the rapid phenotype. On the basis of the evidence now available it is not possible to say whether this association is because slow acetylators develop the disease more frequently or whether they survive longer. In the second group the relevant studies show (1) a greatly increased prevalence of slow acetylators in Gilbert's disease; (2) a confirmed association between the rapid acetylator phenotype and diabetes; (3) a possible association between the rapid acetylator phenotype and breast cancer; (4) a possible association between the slow acetylator phenotype and leprosy in Chinese patients; (5) an earlier age of onset of thyrotoxicosis (Graves' disease) in slow acetylators than in rapid acetylators; (6) no evidence of an association between either phenotype and spontaneous systemic lupus erythematosus. PMID:6387123

  12. Lipase-catalyzed synthesis of acetylated EGCG and antioxidant properties of the acetylated derivatives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    (-)-Epigallocatechin-3-O-gallate (EGCG) acetylated derivatives were prepared by lipase catalyzed acylation of EGCG with vinyl acetate to improve its lipophilicity and expand its application in lipophilic media. The immobilized lipase, Lipozyme RM IM, was found to be the optimum catalyst. The optimiz...

  13. Genetics Home Reference: succinyl-CoA:3-ketoacid CoA transferase deficiency

    MedlinePlus

    ... CoA:3-ketoacid CoA transferase deficiency succinyl-CoA:3-ketoacid CoA transferase deficiency Enable Javascript to view ... PDF Open All Close All Description Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency is an inherited ...

  14. Phosphorylation and inhibition of. gamma. -glutamyl transferase activity by cAMP-dependent protein kinase

    SciTech Connect

    Kolesnichenko, L.S.; Chernov, N.N.

    1986-10-20

    It was shown that preparations of bovine kidney ..gamma..-glutamyl transferase of differing degrees of purity are phosphorylated by cAMP-dependent protein kinase. This is accompanied by a decrease in both the transferase and hydrolase activities of the enzyme. Consequently, ..gamma..-glutamyl transferase may serve as the substrate and target of the regulation of cAMP-dependent protein kinase.

  15. Determination of Acetylation of the Gli Transcription Factors.

    PubMed

    Coni, Sonia; Di Magno, Laura; Canettieri, Gianluca

    2015-01-01

    The Gli transcription factors (Gli1, Gli2, and Gli3) are the final effectors of the Hedgehog (Hh) signaling and play a key role in development and cancer. The activity of the Gli proteins is finely regulated by covalent modifications, such as phosphorylation, ubiquitination, and acetylation. Both Gli1 and Gli2 are acetylated at a conserved lysine, and this modification causes the inhibition of their transcriptional activity. Thus, the acetylation status of these proteins represents a useful marker to monitor Hh activation in pathophysiological conditions. Herein we describe the techniques utilized to detect in vitro and intracellular acetylation of the Gli transcription factors. PMID:26179046

  16. Alcohol during Pregnancy

    MedlinePlus

    ... Home > Pregnancy > Is it safe? > Alcohol during pregnancy Alcohol during pregnancy E-mail to a friend Please ... and fetal alcohol spectrum disorders. How does drinking alcohol during pregnancy affect your baby's health? Drinking alcohol ...

  17. Alcohol Energy Drinks

    MedlinePlus

    ... Home / About Addiction / Alcohol / Alcohol Energy Drinks Alcohol Energy Drinks Read 17728 times font size decrease font size increase font size Print Email Alcohol energy drinks (AEDs) or Caffeinated alcoholic beverages (CABs) are ...

  18. Nalmefene and its use in alcohol dependence.

    PubMed

    Gual, A; Bruguera, P; López-Pelayo, H

    2014-05-01

    Nalmefene is the first available drug approved in the E.U. to reduce alcohol use in alcohol-dependent patients. Reduction in alcohol use in heavy drinkers diminishes mortality risk and socio-economic burden. Nalmefene has shown efficacy at 6 months in alcohol-dependent patients with high or very high drinking risk levels in reducing total alcohol consumption (-7.6 g/day [95% confidence interval (CI): -11.6 to -3.5]; P = 0.0003), heavy drinking days (-2.00 days/month [95% CI: -3.00 to -1.00]; P ⟨ 0.00001) and other secondary outcome measures such as γ-glutamyl transferase, alanine aminotransferase, drinking risk level and Clinical Global Impression. It is generally well tolerated and has limited contraindications and interactions. As-needed dosage is a novel concept in the addictions field, which may overcome limitations of traditional regimens. In the pivotal trials, nalmefene was taken 52% of the days and compliance with the as-needed treatment regimen was good (above 80% of the days) in 68% of the nalmefene-treated patients. A new pharmacological approach combined with a brief psychosocial intervention for alcoholism is available and appears to be feasible, safe and efficacious.

  19. Nalmefene and its use in alcohol dependence.

    PubMed

    Gual, A; Bruguera, P; López-Pelayo, H

    2014-05-01

    Nalmefene is the first available drug approved in the E.U. to reduce alcohol use in alcohol-dependent patients. Reduction in alcohol use in heavy drinkers diminishes mortality risk and socio-economic burden. Nalmefene has shown efficacy at 6 months in alcohol-dependent patients with high or very high drinking risk levels in reducing total alcohol consumption (-7.6 g/day [95% confidence interval (CI): -11.6 to -3.5]; P = 0.0003), heavy drinking days (-2.00 days/month [95% CI: -3.00 to -1.00]; P ⟨ 0.00001) and other secondary outcome measures such as γ-glutamyl transferase, alanine aminotransferase, drinking risk level and Clinical Global Impression. It is generally well tolerated and has limited contraindications and interactions. As-needed dosage is a novel concept in the addictions field, which may overcome limitations of traditional regimens. In the pivotal trials, nalmefene was taken 52% of the days and compliance with the as-needed treatment regimen was good (above 80% of the days) in 68% of the nalmefene-treated patients. A new pharmacological approach combined with a brief psychosocial intervention for alcoholism is available and appears to be feasible, safe and efficacious. PMID:24918835

  20. Chemical Reactivity Window Determines Prodrug Efficiency toward Glutathione Transferase Overexpressing Cancer Cells.

    PubMed

    van Gisbergen, Marike W; Cebula, Marcus; Zhang, Jie; Ottosson-Wadlund, Astrid; Dubois, Ludwig; Lambin, Philippe; Tew, Kenneth D; Townsend, Danyelle M; Haenen, Guido R M M; Drittij-Reijnders, Marie-José; Saneyoshi, Hisao; Araki, Mika; Shishido, Yuko; Ito, Yoshihiro; Arnér, Elias S J; Abe, Hiroshi; Morgenstern, Ralf; Johansson, Katarina

    2016-06-01

    Glutathione transferases (GSTs) are often overexpressed in tumors and frequently correlated to bad prognosis and resistance against a number of different anticancer drugs. To selectively target these cells and to overcome this resistance we previously have developed prodrugs that are derivatives of existing anticancer drugs (e.g., doxorubicin) incorporating a sulfonamide moiety. When cleaved by GSTs, the prodrug releases the cytostatic moiety predominantly in GST overexpressing cells, thus sparing normal cells with moderate enzyme levels. By modifying the sulfonamide it is possible to control the rate of drug release and specifically target different GSTs. Here we show that the newly synthesized compounds, 4-acetyl-2-nitro-benzenesulfonyl etoposide (ANS-etoposide) and 4-acetyl-2-nitro-benzenesulfonyl doxorubicin (ANS-DOX), function as prodrugs for GSTA1 and MGST1 overexpressing cell lines. ANS-DOX, in particular, showed a desirable cytotoxic profile by inducing toxicity and DNA damage in a GST-dependent manner compared to control cells. Its moderate conversion of 500 nmol/min/mg, as catalyzed by GSTA1, seems hereby essential since the more reactive 2,4-dinitrobenzenesulfonyl doxorubicin (DNS-DOX) (14000 nmol/min/mg) did not display a preference for GSTA1 overexpressing cells. DNS-DOX, however, effectively killed GSTP1 (20 nmol/min/mg) and MGST1 (450 nmol/min/mg) overexpressing cells as did the less reactive 4-mononitrobenzenesulfonyl doxorubicin (MNS-DOX) in a MGST1-dependent manner (1.5 nmol/min/mg) as shown previously. Furthermore, we show that the mechanism of these prodrugs involves a reduction in GSH levels as well as inhibition of the redox regulatory enzyme thioredoxin reductase 1 (TrxR1) by virtue of their electrophilic sulfonamide moiety. TrxR1 is upregulated in many tumors and associated with resistance to chemotherapy and poor patient prognosis. Additionally, the prodrugs potentially acted as a general shuttle system for DOX, by overcoming resistance

  1. N-acetylaspartate catabolism determines cytosolic acetyl-CoA levels and histone acetylation in brown adipocytes

    PubMed Central

    Prokesch, A.; Pelzmann, H. J.; Pessentheiner, A. R.; Huber, K.; Madreiter-Sokolowski, C. T.; Drougard, A.; Schittmayer, M.; Kolb, D.; Magnes, C.; Trausinger, G.; Graier, W. F.; Birner-Gruenberger, R.; Pospisilik, J. A.; Bogner-Strauss, J. G.

    2016-01-01

    Histone acetylation depends on the abundance of nucleo-cytoplasmic acetyl-CoA. Here, we present a novel route for cytoplasmic acetyl-CoA production in brown adipocytes. N-acetylaspartate (NAA) is a highly abundant brain metabolite catabolized by aspartoacylase yielding aspartate and acetate. The latter can be further used for acetyl-CoA production. Prior to this work, the presence of NAA has not been described in adipocytes. Here, we show that accumulation of NAA decreases the brown adipocyte phenotype. We increased intracellular NAA concentrations in brown adipocytes via media supplementation or knock-down of aspartoacylase and measured reduced lipolysis, thermogenic gene expression, and oxygen consumption. Combinations of approaches to increase intracellular NAA levels showed additive effects on lipolysis and gene repression, nearly abolishing the expression of Ucp1, Cidea, Prdm16, and Ppara. Transcriptome analyses of aspartoacylase knock-down cells indicate deficiencies in acetyl-CoA and lipid metabolism. Concordantly, cytoplasmic acetyl-CoA levels and global histone H3 acetylation were decreased. Further, activating histone marks (H3K27ac and H3K9ac) in promoters/enhancers of brown marker genes showed reduced acetylation status. Taken together, we present a novel route for cytoplasmic acetyl-CoA production in brown adipocytes. Thereby, we mechanistically connect the NAA pathway to the epigenomic regulation of gene expression, modulating the phenotype of brown adipocytes. PMID:27045997

  2. Alcohol conversion

    DOEpatents

    Wachs, Israel E.; Cai, Yeping

    2002-01-01

    Preparing an aldehyde from an alcohol by contacting the alcohol in the presence of oxygen with a catalyst prepared by contacting an intimate mixture containing metal oxide support particles and particles of a catalytically active metal oxide from Groups VA, VIA, or VIIA, with a gaseous stream containing an alcohol to cause metal oxide from the discrete catalytically active metal oxide particles to migrate to the metal oxide support particles and to form a monolayer of catalytically active metal oxide on said metal oxide support particles.

  3. Lysine Acetylation Activates Mitochondrial Aconitase in the Heart

    PubMed Central

    Fernandes, Jolyn; Weddle, Alexis; Kinter, Caroline S.; Humphries, Kenneth M.; Mather, Timothy; Szweda, Luke I.; Kinter, Michael

    2015-01-01

    High throughput proteomics studies have identified several thousand acetylation sites on over one thousand proteins. Mitochondrial aconitase, the Krebs cycle enzyme that converts citrate to isocitrate, has been identified in many of these reports. Acetylated mitochondrial aconitase has also been identified as a target for sirtuin 3 (SIRT3) catalyzed deacetylation. However, the functional significance of mitochondrial aconitase acetylation has not been determined. Using in vitro strategies, mass spectrometric analyses, and an in vivo mouse model of obesity, we found a significant acetylation-dependent activation of aconitase. Isolated heart mitochondria subjected to in vitro chemical acetylation with either acetic anhydride or acetyl-CoA resulted in increased aconitase activity that was reversed with SIRT3 treatment. Quantitative mass spectrometry was used to measure acetylation at 21 lysine residues and found significant increases with both in vitro treatments. A high fat diet (60% kcal from fat) was used as an in vivo model and also showed significantly increased mitochondrial aconitase activity without changes in protein level. The high fat diet also produced increased aconitase acetylation at multiple sites as measured by the quantitative mass spectrometry assays. Treatment of isolated mitochondria from these mice with SIRT3 abolished the high fat diet-induced activation of aconitase and reduced acetylation. Finally, kinetic analyses found that the increase in activity was a result of increased maximal velocity and molecular modeling suggests the potential for acetylation at K144 to perturb the tertiary structure of the enzyme. The results of this study reveal a novel activation of mitochondrial aconitase by acetylation. PMID:26061789

  4. Overexpression of GalNAc-transferase GalNAc-T3 promotes pancreatic cancer cell growth.

    PubMed

    Taniuchi, K; Cerny, R L; Tanouchi, A; Kohno, K; Kotani, N; Honke, K; Saibara, T; Hollingsworth, M A

    2011-12-01

    O-linked glycans of secreted and membrane-bound proteins have an important role in the pathogenesis of pancreatic cancer by modulating immune responses, inflammation and tumorigenesis. A critical aspect of O-glycosylation, the position at which proteins are glycosylated with N-acetyl-galactosamine on serine and threonine residues, is regulated by the substrate specificity of UDP-GalNAc:polypeptide N-acetylgalactosaminyl-transferases (GalNAc-Ts). Thus, GalNAc-Ts regulate the first committed step in O-glycosylated protein biosynthesis, determine sites of O-glycosylation on proteins and are important for understanding normal and carcinoma-associated O-glycosylation. We have found that one of these enzymes, GalNAc-T3, is overexpressed in human pancreatic cancer tissues and suppression of GalNAc-T3 significantly attenuates the growth of pancreatic cancer cells in vitro and in vivo. In addition, suppression of GalNAc-T3 induces apoptosis of pancreatic cancer cells. Our results indicate that GalNAc-T3 is likely involved in pancreatic carcinogenesis. Modification of cellular glycosylation occurs in nearly all types of cancer as a result of alterations in the expression levels of glycosyltransferases. We report guanine the nucleotide-binding protein, α-transducing activity polypeptide-1 (GNAT1) as a possible substrate protein of GalNAc-T3. GalNAc-T3 is associated with O-glycosylation of GNAT1 and affects the subcellular distribution of GNAT1. Knocking down endogenous GNAT1 significantly suppresses the growth/survival of PDAC cells. Our results imply that GalNAc-T3 contributes to the function of O-glycosylated proteins and thereby affects the growth and survival of pancreatic cancer cells. Thus, substrate proteins of GalNAc-T3 should serve as important therapeutic targets for pancreatic cancers.

  5. Resistance to acetaminophen-induced hepatotoxicity in glutathione S-transferase Mu 1-null mice.

    PubMed

    Arakawa, Shingo; Maejima, Takanori; Fujimoto, Kazunori; Yamaguchi, Takashi; Yagi, Masae; Sugiura, Tomomi; Atsumi, Ryo; Yamazoe, Yasushi

    2012-01-01

    We investigated the role of glutathione S-transferases Mu 1 (GSTM1) in acetaminophen (APAP)-induced hepatotoxicity using Gstm1-null mice. A single oral administration of APAP resulted in a marked increase in plasma alanine aminotransferase accompanied by hepatocyte necrosis 24 hr after administration in wild-type mice, but its magnitude was unexpectedly attenuated in Gstm1-null mice. Therefore, it is suggested that Gstm1-null mice are resistant to APAP-induced hepatotoxicity. To examine the mechanism of this resistance in Gstm1-null mice, we measured phosphorylation of c-jun N-terminal kinase (JNK), which mediates the signal of APAP-induced hepatocyte necrosis, by Western blot analysis 2 and 6 hr after APAP administration. A marked increase in phosphorylated JNK was observed in wild-type mice, but the increase was markedly suppressed in Gstm1-null mice. Therefore, it is suggested that suppressed phosphorylation of JNK may be a main mechanism of the resistance to APAP-induced hepatotoxicity in Gstm1-null mice, although other possibilities of the mechanism cannot be eliminated. Additionally, phosphorylation of glycogen synthase kinase-3β and mitogen-activated protein kinase kinase 4, which are upstream kinases of JNK in APAP-induced hepatotoxicity, were also suppressed in Gstm1-null mice. A decrease in liver total glutathione 2 hr after APAP administration, which is an indicator for exposure to N-acetyl-p-benzoquinoneimine, the reactive metabolite of APAP, were similar in wild-type and Gstm1-null mice. In conclusion, Gstm1-null mice are considered to be resistant to APAP-induced hepatotoxicity perhaps by the suppression of JNK phosphorylation. This study indicates the novel role of GSTM1 as a factor mediating the cellular signal for APAP-induced hepatotoxicity.

  6. Alcoholic ketoacidosis

    MedlinePlus

    Tests may include: Arterial blood gases (measure the acid/base balance and oxygen level in blood) Blood alcohol ... PA: Elsevier Saunders; 2013:chap 161. Seifter JL. Acid-Base disorders. In: Goldman L, Schafer AI, eds. Goldman's ...

  7. Alcohol withdrawal

    MedlinePlus

    ... Seeing or feeling things that aren't there (hallucinations) Seizures Severe confusion ... alcohol withdrawal. You will be watched closely for hallucinations and other signs of delirium tremens. Treatment may ...

  8. An Alternative Strategy for Pan-acetyl-lysine Antibody Generation

    PubMed Central

    Zhang, Qiongyi; Tang, Hui; Brunmeir, Reinhard; Pan, Hong; Karnani, Neerja; Han, Weiping; Zhang, Kangling; Xu, Feng

    2016-01-01

    Lysine acetylation is an important post-translational modification in cell signaling. In acetylome studies, a high-quality pan-acetyl-lysine antibody is key to successful enrichment of acetylated peptides for subsequent mass spectrometry analysis. Here we show an alternative method to generate polyclonal pan-acetyl-lysine antibodies using a synthesized random library of acetylated peptides as the antigen. Our antibodies are tested to be specific for acetyl-lysine peptides/proteins via ELISA and dot blot. When pooled, five of our antibodies show broad reactivity to acetyl-lysine peptides, complementing a commercial antibody in terms of peptide coverage. The consensus sequence of peptides bound by our antibody cocktail differs slightly from that of the commercial antibody. Lastly, our antibodies are tested in a proof-of-concept to analyze the acetylome of HEK293 cells. In total we identified 1557 acetylated peptides from 416 proteins. We thus demonstrated that our antibodies are well-qualified for acetylome studies and can complement existing commercial antibodies. PMID:27606599

  9. Effect of acetaminophen on sulfamethazine acetylation in male volunteers.

    PubMed

    Tahir, I M; Iqbal, T; Saleem, S; Mehboob, H; Akhter, N; Riaz, M

    2016-03-01

    The effect of acetaminophen on sulfamethazine N-acetylation by human N-acetyltrasferase-2 (NAT2) was studied in 19 (n=19) healthy male volunteers in two different phases. In the first phase of the study the volunteers were given an oral dose of sulfamethazine 500 mg alone and blood and urine samples were collected. After the 10-day washout period the same selected volunteers were again administered sulfamethazine 500 mg along with 1000 mg acetaminophen. The acetylation of sulfamethazine by human NAT2 in both phases with and without acetaminophen was determined by HPLC to establish their respective phenotypes. In conclusion obtained statistics of present study revealed that acetaminophen significantly (P<0.0001) decreased sulfamethazine acetylation in plasma of both slow and fast acetylator male volunteers. A highly significant (P<0.0001) decrease in plasma-free and total sulfamethazine concentration was also observed when acetaminophen was co-administered. Urine acetylation status in both phases of the study was found not to be in complete concordance with that of plasma. Acetaminophen significantly (P<0.0001) increased the acetyl, free and total sulfamethazine concentration in urine of both slow and fast acetylators. Urine acetylation analysis has not been found to be a suitable approach for phenotypic studies.

  10. An Alternative Strategy for Pan-acetyl-lysine Antibody Generation.

    PubMed

    Kim, Sun-Yee; Sim, Choon Kiat; Zhang, Qiongyi; Tang, Hui; Brunmeir, Reinhard; Pan, Hong; Karnani, Neerja; Han, Weiping; Zhang, Kangling; Xu, Feng

    2016-01-01

    Lysine acetylation is an important post-translational modification in cell signaling. In acetylome studies, a high-quality pan-acetyl-lysine antibody is key to successful enrichment of acetylated peptides for subsequent mass spectrometry analysis. Here we show an alternative method to generate polyclonal pan-acetyl-lysine antibodies using a synthesized random library of acetylated peptides as the antigen. Our antibodies are tested to be specific for acetyl-lysine peptides/proteins via ELISA and dot blot. When pooled, five of our antibodies show broad reactivity to acetyl-lysine peptides, complementing a commercial antibody in terms of peptide coverage. The consensus sequence of peptides bound by our antibody cocktail differs slightly from that of the commercial antibody. Lastly, our antibodies are tested in a proof-of-concept to analyze the acetylome of HEK293 cells. In total we identified 1557 acetylated peptides from 416 proteins. We thus demonstrated that our antibodies are well-qualified for acetylome studies and can complement existing commercial antibodies.

  11. Global analysis of lysine acetylation in strawberry leaves.

    PubMed

    Fang, Xianping; Chen, Wenyue; Zhao, Yun; Ruan, Songlin; Zhang, Hengmu; Yan, Chengqi; Jin, Liang; Cao, Lingling; Zhu, Jun; Ma, Huasheng; Cheng, Zhongyi

    2015-01-01

    Protein lysine acetylation is a reversible and dynamic post-translational modification. It plays an important role in regulating diverse cellular processes including chromatin dynamic, metabolic pathways, and transcription in both prokaryotes and eukaryotes. Although studies of lysine acetylome in plants have been reported, the throughput was not high enough, hindering the deep understanding of lysine acetylation in plant physiology and pathology. In this study, taking advantages of anti-acetyllysine-based enrichment and high-sensitive-mass spectrometer, we applied an integrated proteomic approach to comprehensively investigate lysine acetylome in strawberry. In total, we identified 1392 acetylation sites in 684 proteins, representing the largest dataset of acetylome in plants to date. To reveal the functional impacts of lysine acetylation in strawberry, intensive bioinformatic analysis was performed. The results significantly expanded our current understanding of plant acetylome and demonstrated that lysine acetylation is involved in multiple cellular metabolism and cellular processes. More interestingly, nearly 50% of all acetylated proteins identified in this work were localized in chloroplast and the vital role of lysine acetylation in photosynthesis was also revealed. Taken together, this study not only established the most extensive lysine acetylome in plants to date, but also systematically suggests the significant and unique roles of lysine acetylation in plants. PMID:26442052

  12. 21 CFR 172.372 - N-Acetyl-L-methionine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.372 N-Acetyl-L-methionine. The food additive N-acetyl-L... section. The minimum amount of the additive to achieve the desired effect must be used, and the...

  13. An Alternative Strategy for Pan-acetyl-lysine Antibody Generation.

    PubMed

    Kim, Sun-Yee; Sim, Choon Kiat; Zhang, Qiongyi; Tang, Hui; Brunmeir, Reinhard; Pan, Hong; Karnani, Neerja; Han, Weiping; Zhang, Kangling; Xu, Feng

    2016-01-01

    Lysine acetylation is an important post-translational modification in cell signaling. In acetylome studies, a high-quality pan-acetyl-lysine antibody is key to successful enrichment of acetylated peptides for subsequent mass spectrometry analysis. Here we show an alternative method to generate polyclonal pan-acetyl-lysine antibodies using a synthesized random library of acetylated peptides as the antigen. Our antibodies are tested to be specific for acetyl-lysine peptides/proteins via ELISA and dot blot. When pooled, five of our antibodies show broad reactivity to acetyl-lysine peptides, complementing a commercial antibody in terms of peptide coverage. The consensus sequence of peptides bound by our antibody cocktail differs slightly from that of the commercial antibody. Lastly, our antibodies are tested in a proof-of-concept to analyze the acetylome of HEK293 cells. In total we identified 1557 acetylated peptides from 416 proteins. We thus demonstrated that our antibodies are well-qualified for acetylome studies and can complement existing commercial antibodies. PMID:27606599

  14. A facile and practical synthesis of N-acetyl enamides.

    PubMed

    Tang, Wenjun; Capacci, Andrew; Sarvestani, Max; Wei, Xudong; Yee, Nathan K; Senanayake, Chris H

    2009-12-18

    A facile and practical method for the synthesis of N-acetyl alpha-arylenamides has been developed from corresponding ketoximes as the starting materials with ferrous acetate as the reducing reagent. This methodology offers mild reaction conditions, simple purification procedures, and high yields for a variety of N-acetyl enamides. PMID:19921804

  15. Medial temporal N-acetyl aspartate in pediatric major depression

    PubMed Central

    MacMaster, Frank P.; Moore, Gregory J; Russell, Aileen; Mirza, Yousha; Taormina, S. Preeya; Buhagiar, Christian; Rosenberg, David R.

    2008-01-01

    The medial temporal cortex (MTC) has been implicated in the pathogenesis of pediatric major depressive disorder (MDD). Eleven MDD-case control pairs underwent proton magnetic resonance spectroscopic imaging. N-acetyl-aspartate was lower in left MTC (27%) in MDD patients versus controls. Lower N-acetyl-aspartate concentrations in MDD patients may reflect reduced neuronal viability. PMID:18703320

  16. Medial temporal N-acetyl-aspartate in pediatric major depression.

    PubMed

    MacMaster, Frank P; Moore, Gregory J; Russell, Aileen; Mirza, Yousha; Taormina, S Preeya; Buhagiar, Christian; Rosenberg, David R

    2008-10-30

    The medial temporal cortex (MTC) has been implicated in the pathogenesis of pediatric major depressive disorder (MDD). Eleven MDD case-control pairs underwent proton magnetic resonance spectroscopic imaging. N-acetyl-aspartate was lower in the left MTC (27%) in MDD patients versus controls. Lower N-acetyl-aspartate concentrations in MDD patients may reflect reduced neuronal viability. PMID:18703320

  17. Study on Dendrobium officinale O-acetyl-glucomannan (Dendronan®): part II. Fine structures of O-acetylated residues.

    PubMed

    Xing, Xiaohui; Cui, Steve W; Nie, Shaoping; Phillips, Glyn O; Goff, H Douglas; Wang, Qi

    2015-03-01

    Main objective of this study was to investigate the detailed structural information about O-acetylated sugar residues in Dendronan(®). A water solution (2%, w/w) of Dendronan(®) was treated with endo-β-mannanase to produce oligosaccharides rich in O-acetylated sugar residues. The oligosaccharides were partly recovered by ethanol precipitation (70%, w/w). The recovered sample (designated Hydrolyzed Dendrobium officinale Polysaccharide, HDOP) had a yield of 24.7% based on the dry weight of Dendronan(®) and was highly O-acetylated. A D2O solution of HDOP (6%, w/w) generated strong signals in (1)H, (13)C, 2D (1)H-(1)H COSY, 2D (1)H-(1)H TOCSY, 2D (1)H-(1)H NOESY, 2D (1)H-(13)C HMQC, and 2D (1)H-(13)C HMBC NMR spectra. Results of NMR analyses showed that the majority of O-acetylated mannoses were mono-substituted with acetyl groups at O-2 or O-3 position. There were small amounts of mannose residues with di-O-acetyl substitution at both O-2 and O-3 positions. Minor levels of mannoses with 6-O-acetyl, 2,6-di-O-acetyl, and 3,6-di-O-acetyl substitutions were also identified. Much information about sugar residue sequence was extracted from 2D (1)H-(13)C HMBC and 2D (1)H-(1)H NOESY spectra. (1)J(C-H) coupling constants of major sugar residues were obtained. Evidences for the existence of branches or O-acetylated glucoses in HDOP were not found. The major structure of Dendronan(®) is shown as follows: [Formula: see text] M: β-D-mannopyranose; G: β-D-glucopyranose; a: O-acetyl group.

  18. Proton mobilities in crambin and glutathione S-transferase

    NASA Astrophysics Data System (ADS)

    Wanderlingh, U. N.; Corsaro, C.; Hayward, R. L.; Bée, M.; Middendorf, H. D.

    2003-08-01

    Using a neutron backscattering spectrometer, the temperature dependence of mean-square atomic displacements derived from window-integrated quasielastic spectra was measured for two D 2O-hydrated proteins: crambin and glutathione S-transferase. Analyses show that the anharmonic dynamics observed around and above 200 K is consistent with a description in terms of proton/deuteron jumps within asymmetric double-minimum potentials. Also determined were activation energies along with estimates of effective masses and average oscillator energies.

  19. Cell biology (Communication arising): Tubulin acetylation and cell motility

    NASA Astrophysics Data System (ADS)

    Palazzo, Alexander; Ackerman, Brian; Gundersen, Gregg G.

    2003-01-01

    Although the protein tubulin is known to undergo several post-translational modifications that accumulate in stable but not dynamic microtubules inside cells, the function of these modifications is unknown. Hubbert et al. have shown that the enzyme HDAC6 (for histone deacetylase 6) reverses the post-translational acetylation of tubulin, and provide evidence that reducing tubulin acetylation enhances cell motility. They also suggest that decreasing tubulin acetylation reduces microtubule stability. However, we find that microtubule stabilization is not promoted by tubulin acetylation. We conclude that the alteration in cell motility observed by Hubbert et al. in cells overexpressing HDAC6 results not from changes in the formation of stable microtubules, but from alterations in the degree of tubulin acetylation.

  20. Novel curcumin analog C66 prevents diabetic nephropathy via JNK pathway with the involvement of p300/CBP-mediated histone acetylation.

    PubMed

    Wang, Yangwei; Wang, Yonggang; Luo, Manyu; Wu, Hao; Kong, Lili; Xin, Ying; Cui, Wenpeng; Zhao, Yunjie; Wang, Jingying; Liang, Guang; Miao, Lining; Cai, Lu

    2015-01-01

    Glomerulosclerosis and interstitial fibrosis represent the key events in development of diabetic nephropathy (DN), with connective tissue growth factor (CTGF), plasminogen activator inhibitor-1 (PAI-1) and fibronectin 1 (FN-1) playing important roles in these pathogenic processes. To investigate whether the plant metabolite curcumin, which exerts epigenetic modulatory properties when applied as a pharmacological agent, may prevent DN via inhibition of the JNK pathway and epigenetic histone acetylation, diabetic and age-matched non-diabetic control mice were administered a 3-month course of curcumin analogue (C66), c-Jun N-terminal kinase inhibitor (JNKi, sp600125), or vehicle alone. At treatment end, half of the mice were sacrificed for analysis and the other half were maintained without treatment for an additional 3 months. Renal JNK phosphorylation was found to be significantly increased in the vehicle-treated diabetic mice, but not the C66- and JNKi-treated diabetic mice, at both the 3-month and 6-month time points. C66 and JNKi treatment also significantly prevented diabetes-induced renal fibrosis and dysfunction. Diabetes-related increases in histone acetylation, histone acetyl transferases' (HATs) activity, and the p300/CBP HAT expression were also significantly attenuated by C66 or JNKi treatment. Chromatin immunoprecipitation assays showed that C66 and JNKi treatments decreased H3-lysine9/14-acetylation (H3K9/14Ac) level and p300/CBP occupancy at the CTGF, PAI-1 and FN-1 gene promoters. Thus, C66 may significantly and persistently prevent renal injury and dysfunction in diabetic mice via down-regulation of diabetes-related JNK activation and consequent suppression of the diabetes-related increases in HAT activity, p300/CBP expression, and histone acetylation.

  1. Epigenetic control of gene expression in the alcoholic brain.

    PubMed

    Ponomarev, Igor

    2013-01-01

    Chronic alcohol exposure causes widespread changes in brain gene expression in humans and animal models. Many of these contribute to cellular adaptations that ultimately lead to behavioral tolerance and alcohol dependence. There is an emerging appreciation for the role of epigenetic processes in alcohol-induced changes in brain gene expression and behavior. For example, chronic alcohol exposure produces changes in DNA and histone methylation, histone acetylation, and microRNA expression that affect expression of multiple genes in various types of brain cells (i.e., neurons and glia) and contribute to brain pathology and brain plasticity associated with alcohol abuse and dependence. Drugs targeting the epigenetic "master regulators" are emerging as potential therapeutics for neurodegenerative disorders and drug addiction.

  2. Epigenetic Control of Gene Expression in the Alcoholic Brain

    PubMed Central

    Ponomarev, Igor

    2013-01-01

    Chronic alcohol exposure causes widespread changes in brain gene expression in humans and animal models. Many of these contribute to cellular adaptations that ultimately lead to behavioral tolerance and alcohol dependence. There is an emerging appreciation for the role of epigenetic processes in alcohol-induced changes in brain gene expression and behavior. For example, chronic alcohol exposure produces changes in DNA and histone methylation, histone acetylation, and microRNA expression that affect expression of multiple genes in various types of brain cells (i.e., neurons and glia) and contribute to brain pathology and brain plasticity associated with alcohol abuse and dependence. Drugs targeting the epigenetic “master regulators” are emerging as potential therapeutics for neurodegenerative disorders and drug addiction. PMID:24313166

  3. Comprehensive profiling of lysine acetylation suggests the widespread function is regulated by protein acetylation in the silkworm, Bombyx mori.

    PubMed

    Nie, Zuoming; Zhu, Honglin; Zhou, Yong; Wu, Chengcheng; Liu, Yue; Sheng, Qing; Lv, Zhengbing; Zhang, Wenping; Yu, Wei; Jiang, Caiying; Xie, Longfei; Zhang, Yaozhou; Yao, Juming

    2015-09-01

    Lysine acetylation in proteins is a dynamic and reversible PTM and plays an important role in diverse cellular processes. In this study, using lysine-acetylation (Kac) peptide enrichment coupled with nano HPLC/MS/MS, we initially identified the acetylome in the silkworms. Overall, a total of 342 acetylated proteins with 667 Kac sites were identified in silkworm. Sequence motifs analysis around Kac sites revealed an enrichment of Y, F, and H in the +1 position, and F was also enriched in the +2 and -2 positions, indicating the presences of preferred amino acids around Kac sites in the silkworm. Functional analysis showed the acetylated proteins were primarily involved in some specific biological processes. Furthermore, lots of nutrient-storage proteins, such as apolipophorin, vitellogenin, storage proteins, and 30 K proteins, were highly acetylated, indicating lysine acetylation may represent a common regulatory mechanism of nutrient utilization in the silkworm. Interestingly, Ser2 proteins, the coating proteins of larval silk, were found to contain many Kac sites, suggesting lysine acetylation may be involved in the regulation of larval silk synthesis. This study is the first to identify the acetylome in a lepidoptera insect, and expands greatly the catalog of lysine acetylation substrates and sites in insects.

  4. Evidence of genotoxicity in lymphocytes of non-smoking alcoholics.

    PubMed

    Santovito, Alfredo; Cervella, Piero; Delpero, Massimiliano

    2015-01-01

    Alcohol abuse is a significant public health issue. Epidemiological studies conducted on different populations consistently showed that consumption of alcoholic beverages is associated with cytogenetic damages and higher risk for several types of cancer. However, the interpretation of many cytogenetic studies resulted complicated because some confounding factors, such as smoking habit, are not always taken into account. In the present study, the frequency of sister chromatid exchanges (SCEs), chromosome aberrations (CAs) and micronuclei (MNs) in cultured human lymphocytes was assessed on 15 alcoholic and 15 non-alcoholic control male subjects. Moreover, considering the implication of the Glutathione S-transferases gene polymorphisms in the genetic susceptibility to alcoholic liver diseases, we considered an important issue to evaluate the relationship between these gene polymorphisms and the cytogenetic damage. In our sample we exclusively considered individuals that did not smoke nor consume drugs for a period of at least 2 years prior to the analysis. Statistically significant differences were found between alcoholics and controls in the frequency of SCEs/cell (P = 0.001), RI value (P = 0.001), CAs (P = 0.002) and CAB (P = 0.002). Vice versa, no significant differences were found between alcoholics and controls in terms of MNs frequency and CBPI value. In both samples, no statistically significant association was found between the analysed GSTs gene polymorphisms and the frequencies of MNs, SCEs and CAs. Finally, among alcoholics we found a positive correlation between SCEs and CAs frequencies and the duration of alcohol abuse.

  5. Detecting alcohol abuse: traditional blood alcohol markers compared to ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEEs) measurement in hair.

    PubMed

    Hastedt, Martin; Büchner, Mara; Rothe, Michael; Gapert, René; Herre, Sieglinde; Krumbiegel, Franziska; Tsokos, Michael; Kienast, Thorsten; Heinz, Andreas; Hartwig, Sven

    2013-12-01

    Alcohol abuse is a common problem in society; however, the technical capabilities of evaluating individual alcohol consumption using objective biomarkers are rather limited at present. In recent years research has focused on alcohol markers using hair analysis but data on performance and reliable cut-off values are still lacking. In this study 169 candidates were tested to compare traditional biomarkers, such as carbohydrate-deficient-transferrin (CDT), gamma glutamyl transferase (GGT), aspartate amino transferase, alanine amino transferase and the mean corpuscular volume of the erythrocytes, with alcohol markers detectable in hair such as ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEEs). This study revealed that EtG, GGT and CDT showed the best results, demonstrating areas under the curve calculated from receiver operating characteristics of 0.941, 0.943 and 0.899 respectively. The lowest false-negative and false-positive rates were obtained by using a combined interpretation system for hair EtG and FAEEs. All markers demonstrated only low to moderate correlations. Optimum cut-off values for differentiation between social and chronic excessive drinking calculated for hair EtG and FAEEs were 28 pg/mg and 0.675 ng/mg, respectively. The critical values published in the "Consensus on Alcohol Markers 2012" by the Society of Hair Testing were confirmed.

  6. A selective and mild glycosylation method of natural phenolic alcohols

    PubMed Central

    Poláková, Monika

    2016-01-01

    Summary Several bioactive natural p-hydroxyphenylalkyl β-D-glucopyranosides, such as vanillyl β-D-glucopyranoside, salidroside and isoconiferin, and their glycosyl analogues were prepared by a simple reaction sequence. The highly efficient synthetic approach was achieved by utilizing acetylated glycosyl bromides as well as aromatic moieties and mild glycosylation promoters. The aglycones, p-O-acetylated arylalkyl alcohols, were prepared by the reduction of the corresponding acetylated aldehydes or acids. Various stereoselective 1,2-trans-O-glycosylation methods were studied, including the DDQ–iodine or ZnO–ZnCl2 catalyst combination. Among them, ZnO–iodine has been identified as a new glycosylation promoter and successfully applied to the stereoselective glycoside synthesis. The final products were obtained by conventional Zemplén deacetylation. PMID:27340444

  7. Deciding to quit drinking alcohol

    MedlinePlus

    ... Alcohol abuse - quitting drinking; Quitting drinking; Quitting alcohol; Alcoholism - deciding to quit ... pubmed/23698791 . National Institute on Alcohol Abuse and Alcoholism. Alcohol and health. www.niaaa.nih.gov/alcohol- ...

  8. Microbial acetyl conjugation of T-2 toxin and its derivatives.

    PubMed Central

    Yoshizawa, T; Onomoto, C; Morooka, N

    1980-01-01

    The acetyl conjugation of T-2 toxin and its derivatives, the 12,13-epoxytrichothecene mycotoxins, was studied by using mycelia of trichothecene-producing strains of Fusarium graminearum, F. nivale, Calonectria nivalis, and F. sporotrichoides, T-2 toxin was efficiently converted into acetyl T-2 toxin by all strains except a T-2 toxin-producing strain of F. sporotrichoides, which hydrolyzed the substrate to HT-2-toxin and neosolaniol. HT-2 toxin was conjugated to 3-acetyl HT-2 toxin as an only product by mycelia of F. graminearum and C. nivalis, but was also resistant to conjugation by both F. nivale and F. sporotrichoides. Neosolaniol was also biotransformed selectively into 3-acetyl neosolaniol by F. graminearum. However, 3-acetyl HT-2 toxin was not acetylated by any of the strains under the conditions employed, but was hydrolyzed to HT-2 toxin by F. graminearum and F. nivale. This is the first report on the biological 3 alpha-O-acetyl conjugation of T-2 toxin and its derivatives. PMID:7396487

  9. Chitosan Molecular Structure as a Function of N-Acetylation

    SciTech Connect

    Franca, Eduardo F.; Freitas, Luiz C.; Lins, Roberto D.

    2011-07-01

    Molecular dynamics simulations have been carried out to characterize the structure and solubility of chitosan nanoparticle-like structures as a function of the deacetylation level (0, 40, 60, and 100%) and the spatial distribution of the N-acetyl groups in the particles. The polysaccharide chains of highly N-deacetylated particles where the N-acetyl groups are uniformly distributed present a high flexibility and preference for the relaxed two-fold helix and five-fold helix motifs. When these groups are confined to a given region of the particle, the chains adopt preferentially a two-fold helix with f and w values close to crystalline chitin. Nanoparticles with up to 40% acetylation are moderately soluble, forming stable aggregates when the N-acetyl groups are unevenly distributed. Systems with 60% or higher N-acetylation levels are insoluble and present similar degrees of swelling regardless the distribution of their N-acetyl groups. Overall particle solvation is highly affected by electrostatic forces resulting from the degree of acetylation. The water mobility and orientation around the polysaccharide chains affects the stability of the intramolecular O3- HO3(n) ... O5(n+ 1) hydrogen bond, which in turn controls particle aggregation.

  10. The Three-Dimensional Structure of the Biotin Carboxylase-Biotin Carboxyl Carrier Protein Complex of E. coli Acetyl-CoA Carboxylase

    PubMed Central

    Broussard, Tyler C.; Kobe, Matthew J.; Pakhomova, Svetlana; Neau, David B.; Price, Amanda E.; Champion, Tyler S.; Waldrop, Grover L.

    2014-01-01

    SUMMARY Acetyl-coenzyme A (acetyl-CoA) carboxylase is a biotin-dependent, multifunctional enzyme that catalyzes the regulated step in fatty acid synthesis. The Escherichia coli enzyme is composed of a homodimeric biotin carboxylase (BC), biotinylated biotin carboxyl carrier protein (BCCP), and an α2β2 heterotetrameric carboxyltransferase. This enzyme complex catalyzes two half-reactions to form malonylcoenzyme A. BC and BCCP participate in the first half-reaction, whereas carboxyltransferase and BCCP are involved in the second. Three-dimensional structures have been reported for the individual subunits; however, the structural basis for how BCCP reacts with the carboxylase or transferase is unknown. Therefore, we report here the crystal structure of E. coli BCCP complexed with BC to a resolution of 2.49 Å. The protein-protein complex shows a unique quaternary structure and two distinct interfaces for each BCCP monomer. These BCCP binding sites are unique compared to phylogenetically related biotin-dependent carboxylases and therefore provide novel targets for developing antibiotics against bacterial acetyl-CoA carboxylase. PMID:23499019

  11. Development of pyrethroid-like fluorescent substrates for glutathione S-transferase

    PubMed Central

    Huang, Huazhang; Yao, Hongwei; Liu, Jun-Yan; Samra, Aman I.; Kamita, Shizuo G.; Cornel, Anthony J.; Hammock, Bruce D.

    2012-01-01

    The availability of highly sensitive substrates is critical for the development of precise and rapid assays for detecting changes in glutathione S-transferase (GST) activity that are associated with GST-mediated metabolism of insecticides. In this study, six pyrethroid-like compounds were synthesized and characterized as substrates for insect and mammalian GSTs. All of the substrates were esters composed of the same alcohol moiety, 7-hydroxy-4-methylcoumarin, and acid moieties that structurally mimic some commonly used pyrethroid insecticides including cypermethrin and cyhalothrin. CpGSTD1, a recombinant Delta class GST from the mosquito Culex pipiens, metabolized our pyrethroid-like substrates with both chemical and geometric (i.e., the cis-isomers were metabolized at 2- to 5-fold higher rates than the corresponding trans-isomers) preference. A GST preparation from mouse liver also metabolized most of our pyrethroid-like substrates with both chemical and geometric preference but at 10- to 170-fold lower rates. CpGSTD1 and mouse GSTs metabolized CDNB, a general GST substrate, at more than 200-fold higher rates than our novel pyrethroid-like substrates. There was a 10-fold difference in the specificity constant (kcat/KM ratio) of CpGSTD1 for CDNB and those of CpGSTD1 for cis-DCVC and cis-TFMCVC suggesting that cis-DCVC and cis-TFMCVC may be useful for the detection of GST-based metabolism of pyrethroids in mosquitoes. PMID:23000005

  12. Fetal alcohol syndrome

    MedlinePlus

    Alcohol in pregnancy; Alcohol-related birth defects; Fetal alcohol effects; FAS ... varies. Almost none of these babies have normal brain development. Infants and children with fetal alcohol syndrome have many different problems, which can be ...

  13. Fetal Alcohol Spectrum Disorders

    MedlinePlus

    ... alcohol can cause a group of conditions called fetal alcohol spectrum disorders (FASDs). Effects can include physical and behavioral problems such ... alcohol syndrome is the most serious type of FASD. People with fetal alcohol syndrome have facial abnormalities, ...

  14. 9-O-Acetylation of sialic acids is catalysed by CASD1 via a covalent acetyl-enzyme intermediate.

    PubMed

    Baumann, Anna-Maria T; Bakkers, Mark J G; Buettner, Falk F R; Hartmann, Maike; Grove, Melanie; Langereis, Martijn A; de Groot, Raoul J; Mühlenhoff, Martina

    2015-01-01

    Sialic acids, terminal sugars of glycoproteins and glycolipids, play important roles in development, cellular recognition processes and host-pathogen interactions. A common modification of sialic acids is 9-O-acetylation, which has been implicated in sialoglycan recognition, ganglioside biology, and the survival and drug resistance of acute lymphoblastic leukaemia cells. Despite many functional implications, the molecular basis of 9-O-acetylation has remained elusive thus far. Following cellular approaches, including selective gene knockout by CRISPR/Cas genome editing, we here show that CASD1--a previously identified human candidate gene--is essential for sialic acid 9-O-acetylation. In vitro assays with the purified N-terminal luminal domain of CASD1 demonstrate transfer of acetyl groups from acetyl-coenzyme A to CMP-activated sialic acid and formation of a covalent acetyl-enzyme intermediate. Our study provides direct evidence that CASD1 is a sialate O-acetyltransferase and serves as key enzyme in the biosynthesis of 9-O-acetylated sialoglycans. PMID:26169044

  15. Acetylation of Mammalian ADA3 Is Required for Its Functional Roles in Histone Acetylation and Cell Proliferation.

    PubMed

    Mohibi, Shakur; Srivastava, Shashank; Bele, Aditya; Mirza, Sameer; Band, Hamid; Band, Vimla

    2016-10-01

    Alteration/deficiency in activation 3 (ADA3) is an essential component of specific histone acetyltransferase (HAT) complexes. We have previously shown that ADA3 is required for establishing global histone acetylation patterns and for normal cell cycle progression (S. Mohibi et al., J Biol Chem 287:29442-29456, 2012, http://dx.doi.org/10.1074/jbc.M112.378901). Here, we report that these functional roles of ADA3 require its acetylation. We show that ADA3 acetylation, which is dynamically regulated in a cell cycle-dependent manner, reflects a balance of coordinated actions of its associated HATs, GCN5, PCAF, and p300, and a new partner that we define, the deacetylase SIRT1. We use mass spectrometry and site-directed mutagenesis to identify major sites of ADA3 acetylated by GCN5 and p300. Acetylation-defective mutants are capable of interacting with HATs and other components of HAT complexes but are deficient in their ability to restore ADA3-dependent global or locus-specific histone acetylation marks and cell proliferation in Ada3-deleted murine embryonic fibroblasts (MEFs). Given the key importance of ADA3-containing HAT complexes in the regulation of various biological processes, including the cell cycle, our study presents a novel mechanism to regulate the function of these complexes through dynamic ADA3 acetylation. PMID:27402865

  16. Evidence for N----O acetyl migration as the mechanism for O acetylation of peptidoglycan in Proteus mirabilis.

    PubMed Central

    Dupont, C; Clarke, A J

    1991-01-01

    O-acetylated peptidoglycan was purified from Proteus mirabilis grown in the presence of specifically radiolabelled glucosamine derivatives, and the migration of the radiolabel was monitored. Mild-base hydrolysis of the isolated peptidoglycan (to release ester-linked acetate) from cells grown in the presence of 40 microM [acetyl-3H]N-acetyl-D-glucosamine resulted in the release of [3H]acetate, as detected by high-pressure liquid chromatography. The inclusion of either acetate, pyruvate, or acetyl phosphate, each at 1 mM final concentration, did not result in a diminution of mild-base-released [3H]acetate levels. No such release of [3H]acetate was observed with peptidoglycan isolated from either Escherichia coli incubated with the same radiolabel or P. mirabilis grown with [1,6-3H]N-acetyl-D-glucosamine or D-[1-14C]glucosamine. These observations support a hypothesis that O acetylation occurs by N----O acetyl transfer within the sacculus. A decrease in [3H]acetate release by mild-base hydrolysis was observed with the peptidoglycan of P. mirabilis cultures incubated in the presence of antagonists of peptidoglycan biosynthesis, penicillin G and D-cycloserine. The absence of free-amino sugars in the peptidoglycan of P. mirabilis but the detection of glucosamine in spent culture broths implies that N----O transacetylation is intimately associated with peptidoglycan turnover. PMID:2066331

  17. Allyl alcohol

    Integrated Risk Information System (IRIS)

    Allyl alcohol ; CASRN 107 - 18 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  18. Propargyl alcohol

    Integrated Risk Information System (IRIS)

    Propargyl alcohol ; CASRN 107 - 19 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  19. Isobutyl alcohol

    Integrated Risk Information System (IRIS)

    Isobutyl alcohol ; CASRN 78 - 83 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  20. Alcohol project

    SciTech Connect

    Not Available

    1980-12-01

    The Great Western Sugar Company has announced plans for the construction of a $300 million plant for the production of fuel grade alcohol from corn. The plant at Reserve, Lousiana, will also produce high fructose corn syrup and animal feed by-products and will employ an additional 200 people.

  1. Alcoholism and Minority Populations.

    ERIC Educational Resources Information Center

    Watts, Thomas D.; Wright, Roosevelt, Jr.

    1991-01-01

    Briefly discusses some aspects of the role of the state and the position of minorities in respect to alcoholism policies and services. Includes case study of a Black alcoholic. Refers readers to studies on Black alcoholism, Native American alcoholism, Hispanic alcoholism, and Asian-American alcoholism. (Author/NB)

  2. Preparation of Biofuel Using Acetylatation of Jojoba Fatty Alcohols and Assessment as a Blend Component in Ultra Low Sulfur Diesel Fuel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The majority of biodiesel fuels are produced from vegetable oils or animal fats by transesterification of oil with alcohol in the presence of a catalyst. In this study, a new class of biofuel is explored by acetylation of fatty alcohols from Jojoba oil. Recently, we reported Jojoba oil methyl este...

  3. Non-oxidative ethanol metabolites as a measure of alcohol intake.

    PubMed

    Maenhout, Thomas M; De Buyzere, Marc L; Delanghe, Joris R

    2013-01-16

    Recent alcohol intake can be monitored by the measurement of indirect biomarkers. Elevated levels of liver enzymes (i.e. gamma-glutamyl transferase (GGT), alanine amino transferase (ALT) and aspartate amino transferase (AST)) in blood are commonly used in clinical practice as an indicator of alcohol-induced liver damage. With the exception of carbohydrate-deficient transferrin (CDT), the specificity of indirect markers is only moderate because many cases of elevated levels are unrelated to alcohol consumption. Because of their intermediate half-life and tendency to accumulate in hair, non-oxidative ethanol metabolites can be used as markers with an intermediate timeframe between ethanol measurements and GGT and CDT with regard to recent alcohol consumption occurring between hours to 1 week. Additionally, these biomarkers offer a high ethanol-specificity in combination with approximately a two-fold higher sensitivity in comparison with indirect alcohol markers. In case of forensic use of direct ethanol metabolites, caution has to be taken in interpretation and pre-analytical pitfalls should be considered.

  4. Partially Acetylated Sugarcane Bagasse For Wicking Oil From Contaminated Wetlands

    EPA Science Inventory

    Sugarcane bagasse was partially acetylated to enhance its oil-wicking ability in saturated environments while holding moisture for hydrocarbon biodegradation. The water sorption capacity of raw bagasse was reduced fourfold after treatment, which indicated considerably increased ...

  5. Acetylation of C/EBPα inhibits its granulopoietic function

    PubMed Central

    Bararia, Deepak; Kwok, Hui Si; Welner, Robert S.; Numata, Akihiko; Sárosi, Menyhárt B.; Yang, Henry; Wee, Sheena; Tschuri, Sebastian; Ray, Debleena; Weigert, Oliver; Levantini, Elena; Ebralidze, Alexander K.; Gunaratne, Jayantha; Tenen, Daniel G.

    2016-01-01

    CCAAT/enhancer-binding protein alpha (C/EBPα) is an essential transcription factor for myeloid lineage commitment. Here we demonstrate that acetylation of C/EBPα at lysine residues K298 and K302, mediated at least in part by general control non-derepressible 5 (GCN5), impairs C/EBPα DNA-binding ability and modulates C/EBPα transcriptional activity. Acetylated C/EBPα is enriched in human myeloid leukaemia cell lines and acute myeloid leukaemia (AML) samples, and downregulated upon granulocyte-colony stimulating factor (G-CSF)- mediated granulocytic differentiation of 32Dcl3 cells. C/EBPα mutants that mimic acetylation failed to induce granulocytic differentiation in C/EBPα-dependent assays, in both cell lines and in primary hematopoietic cells. Our data uncover GCN5 as a negative regulator of C/EBPα and demonstrate the importance of C/EBPα acetylation in myeloid differentiation. PMID:27005833

  6. Acetylation of banana fibre to improve oil absorbency.

    PubMed

    Teli, M D; Valia, Sanket P

    2013-01-30

    Oil spill leaves detrimental effects on the environment, living organisms and economy. In the present work, an attempt is made to provide an efficient, easily deployable method of cleaning up oil spills and recovering of the oil. The work reports the use of banana fibres which were acetylated for oil spill recovery. The product so formed was characterized by FT-IR, TG, SEM and its degree of acetylation was also evaluated. The extent of acetylation was measured by weight percent gain. The oil sorption capacity of the acetylated fibre was higher than that of the commercial synthetic oil sorbents such as polypropylene fibres as well as un-modified fibre. Therefore, these oil sorption-active materials which are also biodegradable can be used to substitute non-biodegradable synthetic materials in oil spill cleanup. PMID:23218302

  7. Data detailing the platelet acetyl-lysine proteome

    PubMed Central

    Aslan, Joseph E.; David, Larry L.; McCarty, Owen J.T.

    2015-01-01

    Here we detail proteomics data that describe the acetyl-lysine proteome of blood platelets (Aslan et al., 2015 [1]). An affinity purification – mass spectrometry (AP-MS) approach was used to identify proteins modified by Nε-lysine acetylation in quiescent, washed human platelets. The data provide insights into potential regulatory mechanisms of platelet function mediated by protein lysine acetylation. Additionally, as platelets are anucleate and lack histone proteins, they offer a unique and valuable system to study the regulation of cytosolic proteins by lysine acetylation. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (Vizcaino et al., 2014 [2]) via with PRIDE partner repository with the dataset identifier PXD002332. PMID:26904711

  8. Data detailing the platelet acetyl-lysine proteome.

    PubMed

    Aslan, Joseph E; David, Larry L; McCarty, Owen J T

    2015-12-01

    Here we detail proteomics data that describe the acetyl-lysine proteome of blood platelets (Aslan et al., 2015 [1]). An affinity purification - mass spectrometry (AP-MS) approach was used to identify proteins modified by Nε-lysine acetylation in quiescent, washed human platelets. The data provide insights into potential regulatory mechanisms of platelet function mediated by protein lysine acetylation. Additionally, as platelets are anucleate and lack histone proteins, they offer a unique and valuable system to study the regulation of cytosolic proteins by lysine acetylation. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (Vizcaino et al., 2014 [2]) via with PRIDE partner repository with the dataset identifier PXD002332. PMID:26904711

  9. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315 Galactose-1-phosphate uridyl transferase test system. (a)...

  10. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315 Galactose-1-phosphate uridyl transferase test system. (a)...

  11. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315 Galactose-1-phosphate uridyl transferase test system. (a)...

  12. Lipase-catalyzed highly enantioselective kinetic resolution of boron-containing chiral alcohols.

    PubMed

    Andrade, Leandro H; Barcellos, Thiago

    2009-07-16

    The first application of enzymes as catalysts to obtain optically pure boron compounds is described. The kinetic resolution of boron-containing chiral alcohols via enantioselective transesterification catalyzed by lipases was studied. Aromatic, allylic, and aliphatic secondary alcohols containing a boronate ester or boronic acid group were resolved by lipase from Candida antartica (CALB), and excellent E values (E > 200) and high enantiomeric excesses (up to >99%) of both remaining substrates and acetylated product were obtained. PMID:19552446

  13. Lipase-catalyzed highly enantioselective kinetic resolution of boron-containing chiral alcohols.

    PubMed

    Andrade, Leandro H; Barcellos, Thiago

    2009-07-16

    The first application of enzymes as catalysts to obtain optically pure boron compounds is described. The kinetic resolution of boron-containing chiral alcohols via enantioselective transesterification catalyzed by lipases was studied. Aromatic, allylic, and aliphatic secondary alcohols containing a boronate ester or boronic acid group were resolved by lipase from Candida antartica (CALB), and excellent E values (E > 200) and high enantiomeric excesses (up to >99%) of both remaining substrates and acetylated product were obtained.

  14. Mechanistic insights into the regulation of metabolic enzymes by acetylation

    PubMed Central

    2012-01-01

    The activity of metabolic enzymes is controlled by three principle levels: the amount of enzyme, the catalytic activity, and the accessibility of substrates. Reversible lysine acetylation is emerging as a major regulatory mechanism in metabolism that is involved in all three levels of controlling metabolic enzymes and is altered frequently in human diseases. Acetylation rivals other common posttranslational modifications in cell regulation not only in the number of substrates it modifies, but also the variety of regulatory mechanisms it facilitates. PMID:22826120

  15. Regulation of S-Adenosylhomocysteine Hydrolase by Lysine Acetylation*

    PubMed Central

    Wang, Yun; Kavran, Jennifer M.; Chen, Zan; Karukurichi, Kannan R.; Leahy, Daniel J.; Cole, Philip A.

    2014-01-01

    S-Adenosylhomocysteine hydrolase (SAHH) is an NAD+-dependent tetrameric enzyme that catalyzes the breakdown of S-adenosylhomocysteine to adenosine and homocysteine and is important in cell growth and the regulation of gene expression. Loss of SAHH function can result in global inhibition of cellular methyltransferase enzymes because of high levels of S-adenosylhomocysteine. Prior proteomics studies have identified two SAHH acetylation sites at Lys401 and Lys408 but the impact of these post-translational modifications has not yet been determined. Here we use expressed protein ligation to produce semisynthetic SAHH acetylated at Lys401 and Lys408 and show that modification of either position negatively impacts the catalytic activity of SAHH. X-ray crystal structures of 408-acetylated SAHH and dually acetylated SAHH have been determined and reveal perturbations in the C-terminal hydrogen bonding patterns, a region of the protein important for NAD+ binding. These crystal structures along with mutagenesis data suggest that such hydrogen bond perturbations are responsible for SAHH catalytic inhibition by acetylation. These results suggest how increased acetylation of SAHH may globally influence cellular methylation patterns. PMID:25248746

  16. Acetyl Radical Generation in Cigarette Smoke: Quantification and Simulations.

    PubMed

    Hu, Na; Green, Sarah A

    2014-10-01

    Free radicals are present in cigarette smoke and can have a negative effect on human health. However, little is known about their formation mechanisms. Acetyl radicals were quantified in tobacco smoke and mechanisms for their generation were investigated by computer simulations. Acetyl radicals were trapped from the gas phase using 3-amino-2, 2, 5, 5-tetramethyl-proxyl (3AP) on solid support to form stable 3AP adducts for later analysis by high performance liquid chromatography (HPLC), mass spectrometry/tandem mass spectrometry (MS-MS/MS) and liquid chromatography-mass spectrometry (LC-MS). Simulations were performed using the Master Chemical Mechanism (MCM). A range of 10-150 nmol/cigarette of acetyl radical was measured from gas phase tobacco smoke of both commerial and research cigarettes under several different smoking conditions. More radicals were detected from the puff smoking method compared to continuous flow sampling. Approximately twice as many acetyl radicals were trapped when a glass filber particle filter (GF/F specifications) was placed before the trapping zone. Simulations showed that NO/NO2 reacts with isoprene, initiating chain reactions to produce hydroxyl radical, which abstracts hydrogen from acealdehyde to generate acetyl radical. These mechanisms can account for the full amount of acetyl radical detected experimentally from cigarette smoke. Similar mechanisms may generate radicals in second hand smoke. PMID:25253993

  17. Acetyl radical generation in cigarette smoke: Quantification and simulations

    NASA Astrophysics Data System (ADS)

    Hu, Na; Green, Sarah A.

    2014-10-01

    Free radicals are present in cigarette smoke and can have a negative effect on human health. However, little is known about their formation mechanisms. Acetyl radicals were quantified in tobacco smoke and mechanisms for their generation were investigated by computer simulations. Acetyl radicals were trapped from the gas phase using 3-amino-2, 2, 5, 5-tetramethyl-proxyl (3AP) on solid support to form stable 3AP adducts for later analysis by high-performance liquid chromatography (HPLC), mass spectrometry/tandem mass spectrometry (MS-MS/MS) and liquid chromatography-mass spectrometry (LC-MS). Simulations were performed using the Master Chemical Mechanism (MCM). A range of 10-150 nmol/cigarette of acetyl radical was measured from gas phase tobacco smoke of both commercial and research cigarettes under several different smoking conditions. More radicals were detected from the puff smoking method compared to continuous flow sampling. Approximately twice as many acetyl radicals were trapped when a glass fiber particle filter (GF/F specifications) was placed before the trapping zone. Simulations showed that NO/NO2 reacts with isoprene, initiating chain reactions to produce hydroxyl radical, which abstracts hydrogen from acetaldehyde to generate acetyl radical. These mechanisms can account for the full amount of acetyl radical detected experimentally from cigarette smoke. Similar mechanisms may generate radicals in second hand smoke.

  18. Electrochemical evaluation of glutathione S-transferase kinetic parameters.

    PubMed

    Enache, Teodor Adrian; Oliveira-Brett, Ana Maria

    2015-02-01

    Glutathione S-transferases (GSTs), are a family of enzymes belonging to the phase II metabolism that catalyse the formation of thioether conjugates between the endogenous tripeptide glutathione and xenobiotic compounds. The voltammetric behaviour of glutathione (GSH), 1-chloro-2,4-dinitrobenzene (CDNB) and glutathione S-transferase (GST), as well as the catalytic conjugation reaction of GSH to CDNB by GST was investigated at room temperature, T=298.15K (25°C), at pH6.5, for low concentration of substrates and enzyme, using differential pulse (DP) voltammetry at a glassy carbon electrode. Only GSH can be oxidized; a sensitivity of 0.14nA/μM and a LOD of 6.4μM were obtained. The GST kinetic parameter electrochemical evaluation, in relation to its substrates, GSH and CDNB, using reciprocal Michaelis-Menten and Lineweaver-Burk double reciprocal plots, was determined. A value of KM~100μM was obtained for either GSH or CDNB, and Vmax varied between 40 and 60μmol/min per mg of GST.

  19. Interstellar Alcohols

    NASA Technical Reports Server (NTRS)

    Charnley, S. B.; Kress, M. E.; Tielens, A. G. G. M.; Millar, T. J.

    1995-01-01

    We have investigated the gas-phase chemistry in dense cores where ice mantles containing ethanol and other alcohols have been evaporated. Model calculations show that methanol, ethanol, propanol, and butanol drive a chemistry leading to the formation of several large ethers and esters. Of these molecules, methyl ethyl ether (CH3OC2H5) and diethyl ether (C2H5)2O attain the highest abundances and should be present in detectable quantities within cores rich in ethanol and methanol. Gas-phase reactions act to destroy evaporated ethanol and a low observed abundance of gas-phase C,H,OH does not rule out a high solid-phase abundance. Grain surface formation mechanisms and other possible gas-phase reactions driven by alcohols are discussed, as are observing strategies for the detection of these large interstellar molecules.

  20. Alcohol use and safe drinking

    MedlinePlus

    ... RISKS OF ALCOHOL Alcohol increases the risk of: Alcoholism Falls, drownings, and other accidents Head, neck, stomach, ... pubmed/23698791 . National Institute on Alcohol Abuse and Alcoholism. Alcohol and your health. www.niaaa.nih.gov/ ...

  1. Alcohol Metabolism and Epigenetics Changes

    PubMed Central

    Zakhari, Samir

    2013-01-01

    Metabolites, including those generated during ethanol metabolism, can impact disease states by binding to transcription factors and/or modifying chromatin structure, thereby altering gene expression patterns. For example, the activities of enzymes involved in epigenetic modifications such as DNA and histone methylation and histone acetylation, are influenced by the levels of metabolites such as nicotinamide adenine dinucleotide (NAD), adenosine triphosphate (ATP), and S-adenosylmethionine (SAM). Chronic alcohol consumption leads to significant reductions in SAM levels, thereby contributing to DNA hypomethylation. Similarly, ethanol metabolism alters the ratio of NAD+ to reduced NAD (NADH) and promotes the formation of reactive oxygen species and acetate, all of which impact epigenetic regulatory mechanisms. In addition to altered carbohydrate metabolism, induction of cell death, and changes in mitochondrial permeability transition, these metabolism-related changes can lead to modulation of epigenetic regulation of gene expression. Understanding the nature of these epigenetic changes will help researchers design novel medications to treat or at least ameliorate alcohol-induced organ damage. PMID:24313160

  2. Elevation of alanine amino transferase and aspartate amino transferase produced by pyoverdin, a photolabile pigment of Pseudomonas fluorescens.

    PubMed

    Eraso, A J; Albesa, I

    1998-01-01

    The effect of three forms pyoverdin on mouse liver was studied. Significant increases of alanine amino transferase (ALT) and aspartate amino transferase (AST) were obtained in mice after ingestion of water with forms A and C. The effect on liver was more evident with A than with C. Pyoverdin was purified by means of salt saturation, solvent extractions and ion-exchange chromatography. Fluorescent peaks obtained in the presence of light were different from those eluted under dark conditions. The relative amounts of pyoverdin A, B and C varied when dark purification procedure was employed. Form A decreased while C increased in the absence of light. Optimum conditions for C were in the dark without iron. When C was exposed to light, it changed to form A. Fast Atom Bombardment (FAB) mass spectrometry of pyoverdin form C gave a form at M+ = 1324 m.u., which is 9 m.u. less than pyoverdin purified in the presence of light. The results suggest that light can influence pyoverdin stability and toxicity. PMID:9888631

  3. Identification of cellular factors binding to acetylated HIV-1 integrase.

    PubMed

    Allouch, Awatef; Cereseto, Anna

    2011-11-01

    The viral protein integrase (IN) catalyzes the integration of the HIV-1 cDNA into the host cellular genome. We have recently demonstrated that IN is acetylated by a cellular histone acetyltransferase, p300, which modifies three lysines located in the C-terminus of the viral factor (Cereseto et al. in EMBO J 24:3070-3081, 2005). This modification enhances IN catalytic activity, as demonstrated by in vitro assays. Consistently, mutations introduced in the targeted lysines greatly decrease the efficiency of HIV-1 integration. Acetylation was proven to regulate protein functions by modulating protein-protein interactions. HIV-1 to efficiently complete its replication steps, including the integration reaction, requires interacting with numerous cellular factors. Therefore, we sought to investigate whether acetylation might modulate the interaction between IN and the cellular factors. To this aim we performed a yeast two-hybrid screening that differs from the screenings so far performed (Rain et al. in Methods 47:291-297, 2009; Studamire and Goff in Retrovirology 5:48, 2008) for using as bait IN constitutively acetylated. From this analysis we have identified thirteen cellular factors involved in transcription, chromatin remodeling, nuclear transport, RNA binding, protein synthesis regulation and microtubule organization. To validate these interactions, binding assays were performed showing that acetylation increases the affinity of IN with specific factors. Nevertheless, few two-hybrid hits bind with the same affinity the acetylated and the unmodified IN. These results further underlie the relevance of IN post-translational modification by acetylation in HIV-1 replication cycle.

  4. [Alcohol and alcoholism: attitudes of nursing students].

    PubMed

    Vargas, Divane; Bittencourt, Marina Nolli

    2013-01-01

    This is a descriptive exploratory study that aimed to verify nursing students' attitudes facing to the alcoholic drinks, alcoholism and alcoholics, according to their position in face of an attitudes scale items. For data collection, it was used the Scale of Attitudes to alcohol, alcoholism and alcoholic, applied to 144 nursing students. The results showed a tendency to negative attitudes of these students in face of alcoholism, alcoholic person and alcoholic drinks, since most participants were placed in category indifferent or disagree with the positive items, agreeing with negative scale items. We conclude that this trend of negative attitudes is connected to insufficient attention given to the subject during the nurses' education, being verified the need for greater importance to be given to this problem.

  5. Geranylgeranyl transferase type II inhibition prevents myeloma bone disease.

    PubMed

    Lawson, Michelle A; Coulton, Les; Ebetino, Frank H; Vanderkerken, Karin; Croucher, Peter I

    2008-12-12

    Geranylgeranyl transferase II (GGTase II) is an enzyme that plays a key role in the isoprenylation of proteins. 3-PEHPC, a novel GGTase II inhibitor, blocks bone resorption and induces myeloma cell apoptosis in vitro. Its effect on bone resorption and tumor growth in vivo is unknown. We investigated the effect of 3-PEHPC on tumor burden and bone disease in the 5T2MM model of multiple myeloma in vivo. 3-PEHPC significantly reduced osteoclast numbers and osteoclast surface. 3-PEHPC prevented the bone loss and the development of osteolytic bone lesions induced by 5T2MM myeloma cells. Treatment with 3-PEHPC also significantly reduced myeloma burden in bone. The magnitude of response was similar to that seen with the bisphosphonate, risedronate. These data show that targeting GGTase II with 3-PEHPC can prevent osteolytic bone disease and reduce tumor burden in vivo, and represents a novel approach to treating tumors that grow in bone.

  6. Pleiotropic Functions of Glutathione S-Transferase P

    PubMed Central

    Zhang, Jie; Grek, Christina; Ye, Zhi-Wei; Manevich, Yefim; Tew, Kenneth D.; Townsend, Danyelle M.

    2016-01-01

    Glutathione S-transferase P (GSTP) is one member of the GST superfamily that is prevalently expressed in mammals. Known to possess catalytic activity through deprotonating glutathione allowing formation of thioether bonds with electrophilic substrates, more recent discoveries have broadened our understanding of the biological roles of this protein. In addition to catalytic detoxification, other properties so far ascribed to GSTP include chaperone functions, regulation of nitric oxide pathways, regulation of a variety of kinase signaling pathways, and participation in the forward reaction of protein S-glutathionylation. The expression of GSTP has been linked with cancer and other human pathologies and more recently even with drug addiction. With respect to human health, polymorphic variants of GSTP may determine individual susceptibility to oxidative stress and/or be critical in the design and development of drugs that have used redox pathways as a discovery platform. PMID:24974181

  7. Glutathione analogue sorbents selectively bind glutathione S-transferase isoenzymes.

    PubMed

    Castro, V M; Kelley, M K; Engqvist-Goldstein, A; Kauvar, L M

    1993-06-01

    Novel affinity sorbents for glutathione S-transferases (GSTs) were created by binding glutathione (GSH) analogues to Sepharose 6B. The GSH molecule was modified at the glycine moiety and at the group attached to the sulphur of cysteine. When tested by affinity chromatography in a flow-through microplate format, several of these sorbents selectively bound GST isoenzymes. gamma E-C(Hx)-phi G (glutathione with a hexyl moiety bound to cysteine and phenylglycine substituted for glycine) specifically bound rat GST 7-7, the Pi-class isoenzyme, from liver, kidney and small intestine. gamma E-C(Bz)-beta A (benzyl bound to cysteine and beta-alanine substituted for glycine) was highly selective for rat subunits 3 and 4, which are Mu-class isoenzymes. By allowing purification of the isoenzymes under mild conditions that preserve activity, the novel sorbents should be useful in characterizing the biological roles of GSTs in both normal animal and cancer tissues.

  8. Glutathione S-transferase class {pi} polymorphism in baboons

    SciTech Connect

    Aivaliotis, M.J.; Cantu, T.; Gilligan, R.

    1995-02-01

    Glutathione S-transferase (GST) comprises a family of isozymes with broad substrate specificities. One or more GST isozymes are present in most animal tissues and function in several detoxification pathways through the conjugation of reduced glutathione with various electrophiles, thereby reducing their potential toxicity. Four soluble GST isozymes encoded by genes on different chromosomes have been identified in humans. The acidic class pi GST, GSTP (previously designated GST-3), is widely distributed in adult tissues and appears to be the only GST isozyme present in leukocytes and placenta. Previously reported electrophoretic analyses of erythrocyte and leukocyte extracts revealed single bands of activity, which differed slightly in mobility between the two cell types, or under other conditions, a two-banded pattern. To our knowledge, no genetically determined polymorphisms have previously been reported in GSTP from any species. We now report a polymorphism of GSTP in baboon leukocytes, and present family data that verifies autosomal codominant inheritance. 14 refs., 2 figs., 1 tab.

  9. Pleiotropic functions of glutathione S-transferase P.

    PubMed

    Zhang, Jie; Grek, Christina; Ye, Zhi-Wei; Manevich, Yefim; Tew, Kenneth D; Townsend, Danyelle M

    2014-01-01

    Glutathione S-transferase P (GSTP) is one member of the GST superfamily that is prevalently expressed in mammals. Known to possess catalytic activity through deprotonating glutathione allowing formation of thioether bonds with electrophilic substrates, more recent discoveries have broadened our understanding of the biological roles of this protein. In addition to catalytic detoxification, other properties so far ascribed to GSTP include chaperone functions, regulation of nitric oxide pathways, regulation of a variety of kinase signaling pathways, and participation in the forward reaction of protein S-glutathionylation. The expression of GSTP has been linked with cancer and other human pathologies and more recently even with drug addiction. With respect to human health, polymorphic variants of GSTP may determine individual susceptibility to oxidative stress and/or be critical in the design and development of drugs that have used redox pathways as a discovery platform.

  10. Aspirin inhibits glucose-6-phosphate dehydrogenase activity in HCT 116 cells through acetylation: Identification of aspirin-acetylated sites

    PubMed Central

    Ai, Guoqiang; Dachineni, Rakesh; Kumar, D. Ramesh; Alfonso, Lloyd F.; Marimuthu, Srinivasan; Bhat, G. Jayarama

    2016-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) catalyzes the first reaction in the pentose phosphate pathway, and generates ribose sugars, which are required for nucleic acid synthesis, and nicotinamide adenine dinucleotide phosphate (NADPH), which is important for neutralization of oxidative stress. The expression of G6PD is elevated in several types of tumor, including colon, breast and lung cancer, and has been implicated in cancer cell growth. Our previous study demonstrated that exposure of HCT 116 human colorectal cancer cells to aspirin caused acetylation of G6PD, and this was associated with a decrease in its enzyme activity. In the present study, this observation was expanded to HT-29 colorectal cancer cells, in order to compare aspirin-mediated acetylation of G6PD and its activity between HCT 116 and HT-29 cells. In addition, the present study aimed to determine the acetylation targets of aspirin on recombinant G6PD to provide an insight into the mechanisms of inhibition. The results demonstrated that the extent of G6PD acetylation was significantly higher in HCT 116 cells compared with in HT-29 cells; accordingly, a greater reduction in G6PD enzyme activity was observed in the HCT 116 cells. Mass spectrometry analysis of aspirin-acetylated G6PD (isoform a) revealed that aspirin acetylated a total of 14 lysine residues, which were dispersed throughout the length of the G6PD protein. One of the important amino acid targets of aspirin included lysine 235 (K235, in isoform a) and this corresponds to K205 in isoform b, which has previously been identified as being important for catalysis. Acetylation of G6PD at several sites, including K235 (K205 in isoform b), may mediate inhibition of G6PD activity, which may contribute to the ability of aspirin to exert anticancer effects through decreased synthesis of ribose sugars and NADPH. PMID:27356773

  11. Relationship of histone acetylation to DNA topology and transcription.

    PubMed

    Krajewski, W A; Luchnik, A N

    1991-12-01

    An autonomously replicating plasmid constructed from bovine papiloma virus (BPV) and pBR322 was stably maintained as a nuclear episome in a mouse cell culture. Addition to a cell culture of sodium butyrate (5 mM) induced an increase in plasmid DNA supercoiling of 3-5 turns, an increase in acetylation of cellular histones, and a decrease in plasmid transcription by 2- to 4-fold. After withdrawal of butyrate, DNA supercoiling began to fluctuate in a wave-like manner with an amplitude of up to 3 turns and a period of 3-4 h. These waves gradually faded by 24 h. The transcription of the plasmid and acetylation of cellular histones also oscillated with the same period. The wave-like alterations were not correlated with the cell cycle, for there was no resumption of DNA replication after butyrate withdrawal for at least 24 h. In vitro chemical acetylation of histones with acetyl adenylate also led to an increase in the superhelical density of plasmid DNA. The parallel changes in transcription, histone acetylation, and DNA supercoiling in vivo may indicate a functional innerconnection. Also, the observed in vivo variation in the level of DNA supercoiling directly indicates the possibility of its natural regulation in eukaryotic cells.

  12. Enzymic synthesis of indole-3-acetyl-1-O-beta-d-glucose. I. Partial purification and characterization of the enzyme from Zea mays

    NASA Technical Reports Server (NTRS)

    Leznicki, A. J.; Bandurski, R. S.

    1988-01-01

    The first enzyme-catalyzed reaction leading from indole-3-acetic acid (IAA) to the myo-inositol esters of IAA is the synthesis of indole-3-acetyl-1-O-beta-D-glucose from uridine-5'-diphosphoglucose (UDPG) and IAA. The reaction is catalyzed by the enzyme, UDPG-indol-3-ylacetyl glucosyl transferase (IAA-glucose-synthase). This work reports methods for the assay of the enzyme and for the extraction and partial purification of the enzyme from kernels of Zea mays sweet corn. The enzyme has an apparent molecular weight of 46,500 an isoelectric point of 5.5, and its pH optimum lies between 7.3 and 7.6. The enzyme is stable to storage at zero degrees but loses activity during column chromatographic procedures which can be restored only fractionally by addition of column eluates. The data suggest either multiple unknown cofactors or conformational changes leading to activity loss.

  13. Behind the Label "Alcoholic."

    ERIC Educational Resources Information Center

    Wright, Deborah M.

    1989-01-01

    Relates individual's personal story of her childhood influenced by her parent's alcoholism, her own alcoholism as a young adult, and her experiences with counseling. Asks others not to reject her because of the label "alcoholic." (ABL)

  14. Breath alcohol test

    MedlinePlus

    Alcohol test - breath ... There are various brands of breath alcohol tests. Each one uses a different method to test the level of alcohol in the breath. The machine may be electronic or manual. One ...

  15. Exploiting the Substrate Promiscuity of Hydroxycinnamoyl-CoA:Shikimate Hydroxycinnamoyl Transferase to Reduce Lignin.

    PubMed

    Eudes, Aymerick; Pereira, Jose H; Yogiswara, Sasha; Wang, George; Teixeira Benites, Veronica; Baidoo, Edward E K; Lee, Taek Soon; Adams, Paul D; Keasling, Jay D; Loqué, Dominique

    2016-03-01

    Lignin poses a major challenge in the processing of plant biomass for agro-industrial applications. For bioengineering purposes, there is a pressing interest in identifying and characterizing the enzymes responsible for the biosynthesis of lignin. Hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyl transferase (HCT; EC 2.3.1.133) is a key metabolic entry point for the synthesis of the most important lignin monomers: coniferyl and sinapyl alcohols. In this study, we investigated the substrate promiscuity of HCT from a bryophyte (Physcomitrella) and from five representatives of vascular plants (Arabidopsis, poplar, switchgrass, pine and Selaginella) using a yeast expression system. We demonstrate for these HCTs a conserved capacity to acylate with p-coumaroyl-CoA several phenolic compounds in addition to the canonical acceptor shikimate normally used during lignin biosynthesis. Using either recombinant HCT from switchgrass (PvHCT2a) or an Arabidopsis stem protein extract, we show evidence of the inhibitory effect of these phenolics on the synthesis of p-coumaroyl shikimate in vitro, which presumably occurs via a mechanism of competitive inhibition. A structural study of PvHCT2a confirmed the binding of a non-canonical acceptor in a similar manner to shikimate in the active site of the enzyme. Finally, we exploited in Arabidopsis the substrate flexibility of HCT to reduce lignin content and improve biomass saccharification by engineering transgenic lines that overproduce one of the HCT non-canonical acceptors. Our results demonstrate conservation of HCT substrate promiscuity and provide support for a new strategy for lignin reduction in the effort to improve the quality of plant biomass for forage and cellulosic biofuels. PMID:26858288

  16. Exploiting the Substrate Promiscuity of Hydroxycinnamoyl-CoA:Shikimate Hydroxycinnamoyl Transferase to Reduce Lignin

    PubMed Central

    Eudes, Aymerick; Pereira, Jose H.; Yogiswara, Sasha; Wang, George; Teixeira Benites, Veronica; Baidoo, Edward E.K.; Lee, Taek Soon; Adams, Paul D.; Keasling, Jay D.; Loqué, Dominique

    2016-01-01

    Lignin poses a major challenge in the processing of plant biomass for agro-industrial applications. For bioengineering purposes, there is a pressing interest in identifying and characterizing the enzymes responsible for the biosynthesis of lignin. Hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyl transferase (HCT; EC 2.3.1.133) is a key metabolic entry point for the synthesis of the most important lignin monomers: coniferyl and sinapyl alcohols. In this study, we investigated the substrate promiscuity of HCT from a bryophyte (Physcomitrella) and from five representatives of vascular plants (Arabidopsis, poplar, switchgrass, pine and Selaginella) using a yeast expression system. We demonstrate for these HCTs a conserved capacity to acylate with p-coumaroyl-CoA several phenolic compounds in addition to the canonical acceptor shikimate normally used during lignin biosynthesis. Using either recombinant HCT from switchgrass (PvHCT2a) or an Arabidopsis stem protein extract, we show evidence of the inhibitory effect of these phenolics on the synthesis of p-coumaroyl shikimate in vitro, which presumably occurs via a mechanism of competitive inhibition. A structural study of PvHCT2a confirmed the binding of a non-canonical acceptor in a similar manner to shikimate in the active site of the enzyme. Finally, we exploited in Arabidopsis the substrate flexibility of HCT to reduce lignin content and improve biomass saccharification by engineering transgenic lines that overproduce one of the HCT non-canonical acceptors. Our results demonstrate conservation of HCT substrate promiscuity and provide support for a new strategy for lignin reduction in the effort to improve the quality of plant biomass for forage and cellulosic biofuels. PMID:26858288

  17. Properties of a Maize Glutathione S-Transferase That Conjugates Coumaric Acid and Other Phenylpropanoids.

    PubMed Central

    Dean, J. V.; Devarenne, T. P.; Lee, I. S.; Orlofsky, L. E.

    1995-01-01

    A glutathione S-transferase (GST) enzyme from corn (Zea mays L. Pioneer hybrid 3906) that is active with p-coumaric acid and other unsaturated phenylpropanoids was purified approximately 97-fold and characterized. The native enzyme appeared to be a monomer with a molecular mass of approximately 30 kD and an apparent isoelectric point at pH 5.2. The enzyme had a pH optimum between 7.5 and 8.0 and apparent Km values of 4.4 and 1.9 mM for reduced glutathione (GSH) and p-coumaric acid, respectively. In addition to p-coumaric acid, the enzyme was also active with o-coumaric acid, m-coumaric acid, trans-cinnamic acid, ferulic acid, and coniferyl alcohol. In addition to GSH, the enzyme could also utilize cysteine as a sulfhydryl source. The enzyme activity measured when GSH and trans-cinnamic acid were used as substrates was enhanced 2.6- and 5.2-fold by the addition of 50 [mu]M p-coumaric acid and 7-hydroxycoumarin, respectively. 1H- and 13C-nuclear magnetic resonance spectroscopic analysis of the conjugate revealed that the enzyme catalyzed the addition of GSH to the olefinic double bond of p-coumaric acid. Based on the high activity and the substrate specificity of this enzyme, it is possible that this enzyme may be involved in the in vivo conjugation of a number of unsaturated phenylpropanoids. PMID:12228522

  18. Dynamic changes in histone acetylation regulate origins of DNA replication

    PubMed Central

    Unnikrishnan, Ashwin; Gafken, Philip R.; Tsukiyama, Toshio

    2011-01-01

    While histone modifications have been implicated in many DNA-dependent processes, their precise role in DNA replication remains largely unknown. Here, we describe a very efficient, single-step method to specifically purify histones located around an origin of replication from S. cerevisiae. Using high-resolution mass spectrometry, we have obtained a comprehensive view of the histone modifications surrounding the origin of replication throughout the cell cycle. We have discovered that histone H3 and H4 acetylation is dynamically regulated around an origin of replication, at the level of multiply-acetylated histones. Furthermore, we find that this acetylation is required for efficient origin activation during S-phase. PMID:20228802

  19. Synthetic biology for engineering acetyl coenzyme A metabolism in yeast.

    PubMed

    Nielsen, Jens

    2014-01-01

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

  20. An acetylation rheostat for the control of muscle energy homeostasis

    PubMed Central

    Menzies, Keir; Auwerx, Johan

    2013-01-01

    In recent years the role of acetylation has gained ground as an essential modulator of intermediary metabolism in skeletal muscle. Imbalance in energy homeostasis or chronic cellular stress, due to diet, aging or disease, translate into alterations in the acetylation levels of key proteins which governs bioenergetics, cellular substrate use and/or changes in mitochondrial content and function. For example, cellular stress induced by exercise or caloric restriction can alter the coordinated activity of acetyltransferases and deacetylases to increase mitochondrial biogenesis and function in order to adapt to low energetic levels. The natural duality of these enzymes, as metabolic sensors and effector proteins, have helped biologists understand how the body can integrate seemingly distinct signaling pathways to control mitochondrial biogenesis, insulin sensitivity, glucose transport, reactive oxygen species handling, angiogenesis and muscle satellite cell proliferation/differentiation. Our review will summarize the recent developments related to acetylation dependent responses following metabolic stress in skeletal muscle. PMID:23999889

  1. An acetylation rheostat for the control of muscle energy homeostasis.

    PubMed

    Menzies, Keir; Auwerx, Johan

    2013-12-01

    In recent years, the role of acetylation has gained ground as an essential modulator of intermediary metabolism in skeletal muscle. Imbalance in energy homeostasis or chronic cellular stress, due to diet, aging, or disease, translate into alterations in the acetylation levels of key proteins which govern bioenergetics, cellular substrate use, and/or changes in mitochondrial content and function. For example, cellular stress induced by exercise or caloric restriction can alter the coordinated activity of acetyltransferases and deacetylases to increase mitochondrial biogenesis and function in order to adapt to low energetic levels. The natural duality of these enzymes, as metabolic sensors and effector proteins, has helped biologists to understand how the body can integrate seemingly distinct signaling pathways to control mitochondrial biogenesis, insulin sensitivity, glucose transport, reactive oxygen species handling, angiogenesis, and muscle satellite cell proliferation/differentiation. Our review will summarize the recent developments related to acetylation-dependent responses following metabolic stress in skeletal muscle. PMID:23999889

  2. Synthesis of polyrotaxanes from acetyl-β-cyclodextrin

    NASA Astrophysics Data System (ADS)

    Ristić, I. S.; Nikolić, L.; Nikolić, V.; Ilić, D.; Budinski-Simendić, J.

    2011-12-01

    Polyrotaxanes are intermediary products in the synthesis of topological gels. They are created by inclusion complex formation of hydrophobic linear macromolecules with cyclodextrins or their derivatives. Then, pairs of cyclodextrin molecules with covalently linkage were practically forming the nodes of the semi-flexible polymer network. Such gels are called topological gels and they can absorb huge quantities of water due to the net flexibility allowing the poly(ethylene oxide) chains to slide through the cyclodextrin cavities, without being pulled out altogether. For polyrotaxane formation poly(ethylene oxide) was used like linear macromolecules. There are hydroxyl groups at poly(ethylene oxide) chains, whereby the linking of the voluminous molecules should be made. To avoid the reaction of cyclodextrin OH groups with stoppers, they should be protected by, e.g., acetylation. In this work, the acetylation of the OH groups of β-cyclodextrin was performed by acetic acid anhydride with iodine as the catalyst. The acetylation reaction was assessed by the FTIR and HPLC method. By the HPLC analysis was found that the acetylation was completed in 20 minutes. Inserting of poly(ethylene oxide) with 4000 g/mol molecule mass into acetyl-β-cyclodextrin with 2:1 poly(ethylene oxide) monomer unit to acetyl-β-cyclodextrin ratio was also monitored by FTIR, and it was found that the process was completed in 12 h at the temperature of 10°C. If the process is performed at temperatures above 10°C, or for periods longer than 12 hours, the process of uncontrolled hydrolysis of acetate groups was initiated.

  3. Complex N-Acetylation of TriethylenetetramineS⃞

    PubMed Central

    Cerrada-Gimenez, Marc; Weisell, Janne; Hyvönen, Mervi T.; Hee Park, Myung; Alhonen, Leena; Vepsäläinen, Jouko

    2011-01-01

    Triethylenetetramine (TETA) is an efficient copper chelator that has versatile clinical potential. We have recently shown that spermidine/spermine-N1-acetyltransferase (SSAT1), the key polyamine catabolic enzyme, acetylates TETA in vitro. Here, we studied the metabolism of TETA in three different mouse lines: syngenic, SSAT1-overexpressing, and SSAT1-deficient (SSAT1-KO) mice. The mice were sacrificed at 1, 2, or 4 h after TETA injection (300 mg/kg i.p.). We found only N1-acetyltriethylenetetramine (N1AcTETA) and/or TETA in the liver, kidney, and plasma samples. As expected, SSAT1-overexpressing mice acetylated TETA at an accelerated rate compared with syngenic and SSAT1-KO mice. It is noteworthy that SSAT1-KO mice metabolized TETA as syngenic mice did, probably by thialysine acetyltransferase, which had a Km value of 2.5 ± 0.3 mM and a kcat value of 1.3 s−1 for TETA when tested in vitro with the human recombinant enzyme. Thus, the present results suggest that there are at least two N-acetylases potentially metabolizing TETA. However, their physiological significance for TETA acetylation requires further studies. Furthermore, we detected chemical intramolecular N-acetyl migration from the N1 to N3 position of N1AcTETA and N1,N8-diacetyltriethylenetetramine in an acidified high-performance liquid chromatography sample matrix. The complex metabolism of TETA together with the intramolecular N-acetyl migration may explain the huge individual variations in the acetylation rate of TETA reported earlier. PMID:21878558

  4. Can we use serum gamma-glutamyl transferase levels to predict early mortality in stroke?

    PubMed Central

    Akinci, Emine; Doğan, Nurettin Özgür; Gümüş, Haluk; Akilli, Nazire belgin

    2014-01-01

    Objective: Serum gamma-glutamyl transferase (GGT) is a marker for alcohol consumption and hepatobiliary diseases. There are reports on the prognostic role of GGT in coronary artery diseases and stroke. The aim of our study was to identify the potential differences in GGT levels in different types of stroke, and to evaluate the correlation between GGT and 30-day mortality. Method: Patients diagnosed with stroke in emergency department between 01.01.2010 and 30.12.2012 was included in the study. Imaging techniques were used to distinguish between hemorrhagic and ischemic stroke. Ischemic strokes were further classified as either atherosclerotic/lacunar or embolic. Parameters including age, gender, vital signs (systolic and diastolic blood pressure), comorbid diseases (HT, DM, CAD, smoking and alcohol consumption), used medications, previous history of stroke, NIHSS score at the time of admission to emergency department, laboratory parameters (glucose, white blood cell count, hemoglobin, platelet, total cholesterol, creatinine) and duration of hospitalization were recorded. Death records were obtained from patients’ medical records. Results: One thousand eighty six patients were included in the study. GGT levels were not significantly different between ischemic and hemorrhagic strokes (p=0.435). On the other hand, GGT levels in embolic strokes were significantly higher compared to atherosclerotic/lacunar strokes (p=0.001). GGT levels [median 24.50 (16.00-43.00)] in Intensive Care Unit patients were significantly higher compared to GGT level [22.00 (15.00-34.25)] in admitted to service beds patients (p=0.015). Median GGT level of deceased patients was 24.00 (16.00-41.25) and median GGT level of alive patients was 22.00 (15.00-35.00). GGT level of deceased patients was significantly higher compared to GGT levels of alive patients (p=0.048). Conclusion: There was no difference in GGT levels between ischemic and hemorrhagic strokes; however, GGT levels in embolic

  5. Establishment of the tree shrew as an alcohol-induced Fatty liver model for the study of alcoholic liver diseases.

    PubMed

    Xing, Huijie; Jia, Kun; He, Jun; Shi, Changzheng; Fang, Meixia; Song, Linliang; Zhang, Pu; Zhao, Yue; Fu, Jiangnan; Li, Shoujun

    2015-01-01

    Currently, the pathogenesis of alcoholic liver diseases (ALDs) is not clear. As a result, there is no effective treatment for ALDs. One limitation is the lack of a suitable animal model for use in studying ALDs. The tree shrew is a lower primate animal, characterized by a high-alcohol diet. This work aimed to establish a fatty liver model using tree shrews and to assess the animals' suitability for the study of ALDs. Tree shrews were treated with alcohol solutions (10% and 20%) for two weeks. Hemophysiology, blood alcohol concentrations (BACs), oxidative stress factors, alcohol metabolic enzymes and hepatic pathology were checked and assayed with an automatic biochemical analyzer, enzyme-linked immunosorbent assay (ELISA), western blot, hematoxylin-eosin (HE) staining and oil red O staining, and magnetic resonance imaging (MRI). Compared with the normal group, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), total cholesterol (TC), triglyceride (TG), reactive oxygen species (ROS), and malondialdehyde (MDA) were significantly enhanced in alcohol-treated tree shrews. However, the activity of reduced glutathione hormone (GSH) and superoxide dismutase (SOD) declined. Notable changes in alcohol dehydrogenase(ADH1), aldehyde dehydrogenase(ALDH2), CYP2E1, UDP-glucuronosyl transferase 1A1 (UGT1A1) and nuclear factor erythroid-related factor 2 (Nrf2) were observed. HE and oil red O staining showed that hepatocyte swelling, hydropic degeneration, and adipohepatic syndrome occurred in the tree shrews. Alcohol can induce fatty liver-like pathological changes and result in alterations in liver function, oxidative stress factors, alcohol metabolism enzymes and Nrf2. Therefore, the established fatty liver model of tree shrews induced by alcohol should be a promising tool for the study of ALDs. PMID:26030870

  6. Characterization of the genes encoding beta-ketoadipate: succinyl-coenzyme A transferase in Pseudomonas putida.

    PubMed Central

    Parales, R E; Harwood, C S

    1992-01-01

    beta-Ketoadipate:succinyl-coenzyme A transferase (beta-ketoadipate:succinyl-CoA transferase) (EC 2.8.3.6) carries out the penultimate step in the conversion of benzoate and 4-hydroxybenzoate to tricarboxylic acid cycle intermediates in bacteria utilizing the beta-ketoadipate pathway. This report describes the characterization of a DNA fragment from Pseudomonas putida that encodes this enzyme. The fragment complemented mutants defective in the synthesis of the CoA transferase, and two proteins of sizes appropriate to encode the two nonidentical subunits of the enzyme were produced in Escherichia coli when the fragment was placed under the control of a phage T7 promoter. DNA sequence analysis revealed two open reading frames, designated pcaI and pcaJ, that were separated by 8 bp, suggesting that they may comprise an operon. A comparison of the deduced amino acid sequence of the P. putida CoA transferase genes with the sequences of two other bacterial CoA transferases and that of succinyl-CoA:3-ketoacid CoA transferase from pig heart suggests that the homodimeric structure of the mammalian enzyme may have resulted from a gene fusion of the bacterial alpha and beta subunit genes during evolution. Conserved functional groups important to the catalytic activity of CoA transferases were also identified. Images PMID:1624453

  7. Acetylated histone H4 is reduced in human gastric adenomas and carcinomas.

    PubMed

    Ono, S; Oue, N; Kuniyasu, H; Suzuki, T; Ito, R; Matsusaki, K; Ishikawa, T; Tahara, E; Yasui, W

    2002-09-01

    Acetylation of core histones is closely linked to transcriptional activation of various genes. The acetylation levels of nucleosomal histones can be modified through a balance of histone acetyltransferases and deacetylases. To elucidate the role of histone acetylation in human gastric carcinogenesis, we studied the status of histone H4 acetylation in gastric carcinoma tissues and corresponding non-neoplastic mucosa. The status of histone acetylation was assessed by examining the expression of acetylated histone H4 through Western blotting and immunohistochemistry using an anti-acetylated histone H4 antibody. The levels of acetylated histone H4 expression were obviously reduced in 72% (13/18) of gastric carcinomas in comparison with non-neoplastic mucosa by Western blotting. In immunohistochemistry, acetylated histone H4 was clearly detected in the nuclei of both non-neoplastic epithelial and stromal cells, whereas the levels of acetylated histone H4 were heterogeneous or reduced in 66% (38/57) of gastric carcinomas and 46% (6/13) of gastric adenomas. Reduced expression of acetylated histone H4 was also observed in some areas of intestinal metaplasia adjacent to carcinomas. Reduction in the expression of acetylated histone H4 was significantly correlated with advanced stage, depth of tumor invasion and lymph node metastasis. These results suggest that low levels of histone acetylation may be closely associated with the development and progression of gastric carcinomas, possibly through alteration of gene expression.

  8. [Subclinical alcoholic optic neuritis without vitamin deficiency].

    PubMed

    Dally, S; Deplus, S; Delvert, S; Buisine, A; Hispard, E; Girre, C

    1985-01-01

    Vitamin B1, Folic acid Vitamin B12, whole blood Lead level, and plasma Zinc level were determined in 82 patients admitted to an alcoholism rehabilitation program. Each patient was examined for an optic neuritis. Thirty-two of the patients had sub-clinical abnormalities suggestive of optic neuritis like dyschromatopsias and/or field visual defects. No differences were found in the blood levels of Vitamin B1, Folic acid, and Vitamin B12 between the 32% affected and the 68% unaffected subjects. Moreover vitamins blood levels were found to be within the limits of normal values in both groups. A negative correlation between whole blood Lead levels and plasma Zinc levels was found. When an optic neuritis occurs the lead level tends to be higher and the Zinc lower. Abnormalities of the more usual alcoholism tests: gamma glutamyl Transpeptidase (gamma GT), mean red cell volume (V.G.M.) and glutamic Oxaloacetic transferase (T.G.O.), were more pronounced in alcoholics with optic neuritis.

  9. Health risks of alcohol use

    MedlinePlus

    Alcoholism - risks; Alcohol abuse - risks; Alcohol dependence - risks; Risky drinking ... Beer, wine, and liquor all contain alcohol. If you are drinking any of these, you are using alcohol. Your drinking patterns may vary, depending on who you are with ...

  10. MATERNAL SMOKING DURING PREGNANCY, GENETIC VARIATION OF ACETYL-N-TRANSFERASES NAT1 AND NAT2, AND RISK FOR OROFACIAL CLEFTS. (R828292)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  11. Genetic Control of Differential Acetylation in Diabetic Rats

    PubMed Central

    Kaisaki, Pamela J.; Otto, Georg W.; McGouran, Joanna F.; Toubal, Amine; Argoud, Karène; Waller-Evans, Helen; Finlay, Clare; Caldérari, Sophie; Bihoreau, Marie-Thérèse; Kessler, Benedikt M.; Gauguier, Dominique; Mott, Richard

    2014-01-01

    Post-translational protein modifications such as acetylation have significant regulatory roles in metabolic processes, but their relationship to both variation in gene expression and DNA sequence is unclear. We address this question in the Goto-Kakizaki (GK) rat inbred strain, a model of polygenic type 2 diabetes. Expression of the NAD-dependent deacetylase Sirtuin-3 is down-regulated in GK rats compared to normoglycemic Brown Norway (BN) rats. We show first that a promoter SNP causes down-regulation of Sirtuin-3 expression in GK rats. We then use mass-spectrometry to identify proteome-wide differential lysine acetylation of putative Sirtuin-3 protein targets in livers of GK and BN rats. These include many proteins in pathways connected to diabetes and metabolic syndrome. We finally sequence GK and BN liver transcriptomes and find that mRNA expression of these targets does not differ significantly between GK and BN rats, in contrast to other components of the same pathways. We conclude that physiological differences between GK and BN rats are mediated by a combination of differential protein acetylation and gene transcription and that genetic variation can modulate acetylation independently of expression. PMID:24743600

  12. SCANDIUM TRIFLATE CATALYZED ACETYLATION OF STARCH UNDER MILD CONDITIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scandium (III) trifluoromethan sulfonate (Sc(OTf)3) was investigated as a catalyst for the acetylation of starch in order to determine the potential for preparing new types of starch esters under mild conditions. At room temperature, dry granular corn starch reacts with acetic anhydride in the pres...

  13. Mass spectrometry-based detection of protein acetylation

    PubMed Central

    Li, Yu; Silva, Jeffrey C.; Skinner, Mary E.; Lombard, David B.

    2014-01-01

    Summary Improved sample preparation techniques and increasingly sensitive mass spectrometry (MS) analysis have revolutionized the study of protein post-translational modifications (PTMs). Here, we describe a general approach for immunopurification and MS-based identification of acetylated proteins in biological samples. This approach is useful characterizing changes in the acetylome in response to biological interventions (1). PMID:24014401

  14. Tubulin acetylation: responsible enzymes, biological functions and human diseases.

    PubMed

    Li, Lin; Yang, Xiang-Jiao

    2015-11-01

    Microtubules have important functions ranging from maintenance of cell morphology to subcellular transport, cellular signaling, cell migration, and formation of cell polarity. At the organismal level, microtubules are crucial for various biological processes, such as viral entry, inflammation, immunity, learning and memory in mammals. Microtubules are subject to various covalent modifications. One such modification is tubulin acetylation, which is associated with stable microtubules and conserved from protists to humans. In the past three decades, this reversible modification has been studied extensively. In mammals, its level is mainly governed by opposing actions of α-tubulin acetyltransferase 1 (ATAT1) and histone deacetylase 6 (HDAC6). Knockout studies of the mouse enzymes have yielded new insights into biological functions of tubulin acetylation. Abnormal levels of this modification are linked to neurological disorders, cancer, heart diseases and other pathological conditions, thereby yielding important therapeutic implications. This review summarizes related studies and concludes that tubulin acetylation is important for regulating microtubule architecture and maintaining microtubule integrity. Together with detyrosination, glutamylation and other modifications, tubulin acetylation may form a unique 'language' to regulate microtubule structure and function.

  15. Lysine Acetylation Facilitates Spontaneous DNA Dynamics in the Nucleosome.

    PubMed

    Kim, Jongseong; Lee, Jaehyoun; Lee, Tae-Hee

    2015-12-01

    The nucleosome, comprising a histone protein core wrapped around by DNA, is the fundamental packing unit of DNA in cells. Lysine acetylation at the histone core elevates DNA accessibility in the nucleosome, the mechanism of which remains largely unknown. By employing our recently developed hybrid single molecule approach, here we report how the structural dynamics of DNA in the nucleosome is altered upon acetylation at histone H3 lysine 56 (H3K56) that is critical for elevated DNA accessibility. Our results indicate that H3K56 acetylation facilitates the structural dynamics of the DNA at the nucleosome termini that spontaneously and repeatedly open and close on a ms time scale. The results support a molecular mechanism of histone acetylation in catalyzing DNA unpacking whose efficiency is ultimately limited by the spontaneous DNA dynamics at the nucleosome temini. This study provides the first and unique experimental evidence revealing a role of protein chemical modification in directly regulating the kinetic stability of the DNA packing unit.

  16. Lysine Ubiquitination and Acetylation of Human Cardiac 20S Proteasomes

    PubMed Central

    Lau, Edward; Choi, Howard JH; Ng, Dominic CM; Meyer, David; Fang, Caiyun; Li, Haomin; Wang, Ding; Zelaya, Ivette M; Yates, John R; Lam, Maggie PY

    2016-01-01

    Purpose Altered proteasome functions are associated with multiple cardiomyopathies. While the proteasome targets poly-ubiquitinated proteins for destruction, it itself is modifiable by ubiquitination. We aim to identify the exact ubiquitination sites on cardiac proteasomes and examine whether they are also subject to acetylations. Experimental design Assembled cardiac 20S proteasome complexes were purified from five human hearts with ischemic cardiomyopathy, then analyzed by high-resolution MS to identify ubiquitination and acetylation sites. We developed a library search strategy that may be used to complement database search in identifying PTM in different samples. Results We identified 63 ubiquitinated lysines from intact human cardiac 20S proteasomes. In parallel, 65 acetylated residues were also discovered, 39 of which shared with ubiquitination sites. Conclusion and clinical relevance This is the most comprehensive characterization of cardiac proteasome ubiquitination to-date. There are significant overlaps between the discovered ubiquitination and acetylation sites, permitting potential crosstalk in regulating proteasome functions. The information presented here will aid future therapeutic strategies aimed at regulating the functions of cardiac proteasomes. PMID:24957502

  17. Acetylation mediates Cx43 reduction caused by electrical stimulation

    PubMed Central

    Meraviglia, Viviana; Azzimato, Valerio; Colussi, Claudia; Florio, Maria Cristina; Binda, Anna; Panariti, Alice; Qanud, Khaled; Suffredini, Silvia; Gennaccaro, Laura; Miragoli, Michele; Barbuti, Andrea; Lampe, Paul D.; Gaetano, Carlo; Pramstaller, Peter P.; Capogrossi, Maurizio C.; Recchia, Fabio A.; Pompilio, Giulio; Rivolta, Ilaria; Rossini, Alessandra

    2015-01-01

    Communication between cardiomyocytes depends upon Gap Junctions (GJ). Previous studies have demonstrated that electrical stimulation induces GJ remodeling and modifies histone acetylases (HAT) and deacetylases (HDAC) activities, although these two results have not been linked. The aim of this work was to establish whether electrical stimulation modulates GJ-mediated cardiac cell-cell communication by acetylation-dependent mechanisms. Field stimulation of HL-1 cardiomyocytes at 0.5 Hz for 24 hours significantly reduced Connexin43 (Cx43) expression and cell-cell communication. HDAC activity was down-regulated whereas HAT activity was not modified resulting in increased acetylation of Cx43. Consistent with a post-translational mechanism, we did not observe a reduction in Cx43 mRNA in electrically stimulated cells, while the proteasomal inhibitor MG132 maintained Cx43 expression. Further, the treatment of paced cells with the HAT inhibitor Anacardic Acid maintained both the levels of Cx43 and cell-cell communication. Finally, we observed increased acetylation of Cx43 in the left ventricles of dogs subjected to chronic tachypacing as a model of abnormal ventricular activation. In conclusion, our findings suggest that altered electrical activity can regulate cardiomyocyte communication by influencing the acetylation status of Cx43. PMID:26264759

  18. 21 CFR 172.372 - N-Acetyl-L-methionine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... amino acid methionine formed by addition of an acetyl group to the alpha-amino group of methionine. It... amino acid) by weight of the total protein of the finished food, including the amount naturally present... of the additive contained therein. (2) The amounts of additive and each amino acid contained in...

  19. 21 CFR 172.372 - N-Acetyl-L-methionine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... amino acid methionine formed by addition of an acetyl group to the alpha-amino group of methionine. It... amino acid) by weight of the total protein of the finished food, including the amount naturally present... of the additive contained therein. (2) The amounts of additive and each amino acid contained in...

  20. 21 CFR 172.372 - N-Acetyl-L-methionine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... amino acid methionine formed by addition of an acetyl group to the alpha-amino group of methionine. It... amino acid) by weight of the total protein of the finished food, including the amount naturally present... of the additive contained therein. (2) The amounts of additive and each amino acid contained in...

  1. Inactivation of Anopheles gambiae Glutathione Transferase ε2 by Epiphyllocoumarin

    PubMed Central

    Marimo, Patience; Hayeshi, Rose; Mukanganyama, Stanley

    2016-01-01

    Glutathione transferases (GSTs) are part of a major family of detoxifying enzymes that can catalyze the reductive dehydrochlorination of dichlorodiphenyltrichloroethane (DDT). The delta and epsilon classes of insect GSTs have been implicated in conferring resistance to this insecticide. In this study, the inactivation of Anopheles gambiae GSTε2 by epiphyllocoumarin (Tral 1) was investigated. Recombinant AgGSTε2 was expressed in Escherichia coli cells containing a pET3a-AGSTε2 plasmid and purified by affinity chromatography. Tral 1 was shown to inactivate GSTε2 both in a time-dependent manner and in a concentration-dependent manner. The half-life of GSTε2 in the presence of 25 μM ethacrynic acid (ETA) was 22 minutes and with Tral 1 was 30 minutes, indicating that Tral 1 was not as efficient as ETA as an inactivator. The inactivation parameters kinact and KI were found to be 0.020 ± 0.001 min−1 and 7.5 ± 2.1 μM, respectively, after 90 minutes of incubation. Inactivation of GSTε2 by Tral 1 implies that Tral 1 covalently binds to this enzyme in vitro and would be expected to exhibit time-dependent effects on the enzyme in vivo. Tral 1, therefore, would produce irreversible effects when used together with dichlorodiphenyltrichloroethane (DDT) in malaria control programmes where resistance is mediated by GSTs. PMID:26925266

  2. Crystal structure of E. coli lipoprotein diacylglyceryl transferase

    PubMed Central

    Mao, Guotao; Zhao, Yan; Kang, Xusheng; Li, Zhijie; Zhang, Yan; Wang, Xianping; Sun, Fei; Sankaran, Krishnan; Zhang, Xuejun C.

    2016-01-01

    Lipoprotein biogenesis is essential for bacterial survival. Phosphatidylglycerol:prolipoprotein diacylglyceryl transferase (Lgt) is an integral membrane enzyme that catalyses the first reaction of the three-step post-translational lipid modification. Deletion of the lgt gene is lethal to most Gram-negative bacteria. Here we present the crystal structures of Escherichia coli Lgt in complex with phosphatidylglycerol and the inhibitor palmitic acid at 1.9 and 1.6 Å resolution, respectively. The structures reveal the presence of two binding sites and support the previously reported structure–function relationships of Lgt. Complementation results of lgt-knockout cells with different mutant Lgt variants revealed critical residues, including Arg143 and Arg239, that are essential for diacylglyceryl transfer. Using a GFP-based in vitro assay, we correlated the activities of Lgt with structural observations. Together, the structural and biochemical data support a mechanism whereby substrate and product, lipid-modified lipobox-containing peptide, enter and leave the enzyme laterally relative to the lipid bilayer. PMID:26729647

  3. Benzene oxide is a substrate for glutathione S-transferases.

    PubMed

    Zarth, Adam T; Murphy, Sharon E; Hecht, Stephen S

    2015-12-01

    Benzene is a known human carcinogen which must be activated to benzene oxide (BO) to exert its carcinogenic potential. BO can be detoxified in vivo by reaction with glutathione and excretion in the urine as S-phenylmercapturic acid. This process may be catalyzed by glutathione S-transferases (GSTs), but kinetic data for this reaction have not been published. Therefore, we incubated GSTA1, GSTT1, GSTM1, and GSTP1 with glutathione and BO and quantified the formation of S-phenylglutathione. Kinetic parameters were determined for GSTT1 and GSTP1. At 37 °C, the putative Km and Vmax values for GSTT1 were 420 μM and 450 fmol/s, respectively, while those for GSTP1 were 3600 μM and 3100 fmol/s. GSTA1 and GSTM1 did not exhibit sufficient activity for determination of kinetic parameters. We conclude that GSTT1 is a critical enzyme in the detoxification of BO and that GSTP1 may also play an important role, while GSTA1 and GSTM1 seem to be less important.

  4. Mannosyl transferase activity in homogenates of adult Schistosoma mansoni.

    PubMed

    Rumjanek, F D; Smithers, S R

    1978-08-01

    Homogenates of adult Schistosoma mansoni contain enzymes which are capable of transferring [14C]mannose from GDP[U-14C]mannose to a lipid acceptor which migrates as a single peak on a silica gel thin-layer plate. This lipid may belong to the class of polyprenol monophosphates which are intermediate elements in the glycosylation of nascent proteins. The schistosome mannosyl transferase activity is associated with membranous particles and is dependent on the presence of Mn2+. However, other divalent metals such as Mg2+ or Ca2+ can, in decreasing order of efficiency, replace Mn2+. When UDP[U-14C]glucose was incubated with the homogenates in the same conditions, relatively little label was transferred to the lipid acceptor. Live worms incubated in a medium containing GDP[U-14C]mannose seem to incorporate the label preferentially on the tegument and on adjacent subtegumental structures. By adding foetal calf serum to the medium, incorporation of the label can be stimulated.

  5. Glutathione S-transferase, incense burning and asthma in children.

    PubMed

    Wang, I-J; Tsai, C-H; Chen, C-H; Tung, K-Y; Lee, Y L

    2011-06-01

    Incense burning is a popular practice in many family homes and temples. However, little is known about the effects of indoor incense burning and genetic polymorphisms on asthma. This study evaluated the effects of indoor incense burning and glutathione S-transferase (GST) genetic polymorphisms on asthma and wheeze. In 2007, 3,764 seventh-grade schoolchildren (mean±sd age 12.42±0.65 yrs) were evaluated using a standard questionnaire for information about respiratory symptoms and environmental exposures. Multiple logistic regressions were performed to assess the association between GST polymorphisms and incense burning frequency on asthma and wheeze, after adjusting for potential confounders. The frequency of incense burning at home was associated with increased risk of current asthma (p=0.05), medication use (p=0.03) and exercise wheeze (p=0.001). GST1 (GSTT1) null genotypes were associated with current asthma (OR 1.43, 95% CI 1.00-2.04) and medication use (OR 1.46, 95% CI 1.01-2.22). GSTT1 showed a significant interactive effect with incense burning on current asthma, current wheeze and nocturnal wheeze. The frequency of incense burning was associated with increased risk of current asthma, medication use, lifetime wheeze, nocturnal wheeze and exercise wheeze in an exposure-response manner among children with GSTT1 null genotype (p<0.05). Incense burning is a risk factor for asthma and wheezing, especially in GSTT1 genetically susceptible children.

  6. Glucuronyl transferase deficiency and mild hereditary spherocytosis: effect of splenectomy.

    PubMed

    Eber, S W; Ullrich, D; Speer, C P; Armbrust, R; Schröter, W

    1988-08-01

    In a 6-year-old girl an association of hereditary spherocytosis and a defect in hepatic bilirubin metabolism has been found. The patient suffered from mild compensated haemolytic anaemia and excessive hyperbilirubinaemia (maximum concentration 581 mumol/l), the serum activity of liver enzymes was slightly increased. Examination of the erythrocyte membrane proteins revealed a deficiency of the major membrane skeletal protein, spectrin (about 75% of normal) which is probably the basic genetic defect of hereditary spherocytosis. Examination of the patient's family revealed a recessive mode of inheritance. The concentration of bilirubin conjugates in the patient's serum was decreased due to a reduced UDP-glucuronyl transferase activity found in homogenates of liver tissue. Histological liver examination showed an intrahepatic cholestasis, which is a secondary and reversible alteration resulting from severe hyperbilirubinaemia. After splenectomy, normalization of the increased haemolysis and hepatic dysfunction was observed. The excessive hyperbilirubinaemia can be explained by the association of an increased bilirubin load due to haemolytic anaemia and the diminished hepatic conjugation of bilirubin.

  7. Nurses' Attitudes towards Alcoholics.

    ERIC Educational Resources Information Center

    Speer, Rita D.

    Nurses' attitudes toward the alcoholic can have a profound impact on the person suffering from alcoholism. These attitudes can affect the alcoholic's care and even whether the alcoholic chooses to recover. This study investigated attitudes of approximately 68 nurses employed in hospitals, 49 nurses in treatment facilities, 58 nursing students, and…

  8. Internet Alcohol Marketing and Underage Alcohol Use

    PubMed Central

    McClure, Auden C.; Tanski, Susanne E.; Li, Zhigang; Jackson, Kristina; Morgenstern, Matthis; Li, Zhongze; Sargent, James D.

    2016-01-01

    BACKGROUND AND OBJECTIVE Internet alcohol marketing is not well studied despite its prevalence and potential accessibility and attractiveness to youth. The objective was to examine longitudinal associations between self-reported engagement with Internet alcohol marketing and alcohol use transitions in youth. METHODS A US sample of 2012 youths aged 15 to 20 was surveyed in 2011. An Internet alcohol marketing receptivity score was developed, based on number of positive responses to seeing alcohol advertising on the Internet, visiting alcohol brand Web sites, being an online alcohol brand fan, and cued recall of alcohol brand home page images. We assessed the association between baseline marketing receptivity and both ever drinking and binge drinking (≥6 drinks per occasion) at 1-year follow-up with multiple logistic regression, controlling for baseline drinking status, Internet use, sociodemographics, personality characteristics, and peer or parent drinking. RESULTS At baseline, ever-drinking and binge-drinking prevalence was 55% and 27%, respectively. Many (59%) reported seeing Internet alcohol advertising, but few reported going to an alcohol Web site (6%) or being an online fan (3%). Higher Internet use, sensation seeking, having family or peers who drank, and past alcohol use were associated with Internet alcohol marketing receptivity, and a score of 1 or 2 was independently associated with greater adjusted odds of initiating binge drinking (odds ratio 1.77; 95% confidence interval, 1.13–2.78 and odds ratio 2.15; 95% confidence interval, 1.06–4.37 respectively) but not with initiation of ever drinking. CONCLUSIONS Although high levels of engagement with Internet alcohol marketing were uncommon, most underage youths reported seeing it, and we found a prospective association between receptivity to this type of alcohol marketing and future problem drinking, making additional research and ongoing surveillance important. PMID:26738886

  9. Alcohol and bone.

    PubMed

    Mikosch, Peter

    2014-01-01

    Alcohol is widely consumed across the world in different cultural and social settings. Types of alcohol consumption differ between (a) light, only occasional consumption, (b) heavy chronic alcohol consumption, and (c) binge drinking as seen as a new pattern of alcohol consumption among teenagers and young adults. Heavy alcohol consumption is detrimental to many organs and tissues, including bones. Osteoporosis is regularly mentioned as a secondary consequence of alcoholism, and chronic alcohol abuse is established as an independent risk factor for osteoporosis. The review will present the different mechanisms and effects of alcohol intake on bone mass, bone metabolism, and bone strength, including alcoholism-related "life-style factors" such as malnutrition, lack of exercise, and hormonal changes as additional causative factors, which also contribute to the development of osteoporosis due to alcohol abuse. PMID:24477631

  10. [Alcohol and arrhythmias].

    PubMed

    Pfeiffer, D; Jurisch, D; Neef, M; Hagendorff, A

    2016-09-01

    The effects of alcohol on induction of arrhythmias is dose-dependent, independent of preexisting cardiovascular diseases or heart failure and can affect otherwise healthy subjects. While the probability of atrial fibrillation increases with the alcohol dosage, events of sudden cardiac death are less frequent with low and moderate consumption but occur more often in heavy drinkers with alcoholic cardiomyopathy. Men are first affected at higher dosages of alcohol but women can suffer from arrhythmias at lower dosages. Thromboembolisms and ischemic stroke can occur less often at lower dosages of alcohol; however, hemorrhagic stroke and subarachnoid hemorrhage are increased with higher alcohol dosages. Recognizable protective mechanisms of alcohol with respect to cardiovascular diseases only occur with lower amounts of alcohol of less than 10 g per day. Underlying mechanisms explain these controversial effects. Specific therapeutic options for alcohol-related arrhythmias apart from abstinence from alcohol consumption are not known. PMID:27582366

  11. Isolation of a mutant Arabidopsis plant that lacks N-aetyl glucosaminyl transferase I and is unable to synthesize Golgi-modified complex N-linked glycans

    SciTech Connect

    Schaewen, A. von; O'Neill, J.; Chrispeels, M.J. ); Sturm, A. )

    1993-08-01

    The complex asparagine-linked glycans of plant glycoproteins, characterized by the presence of [beta]1[yields]2 xylose and [alpha]1[yields]3 fucose residues, are derived from typical mannose[sub 9](N-acetylglucosamine)[sub 2] (Man[sub 9]GlcNAc[sub 2]) N-linked glycans through the activity of a series of glycosidases and glycosyl transferases in the Golgi apparatus. By screening leaf extracts with an antiserum against complex glycans, we isolated a mutant of Arbidopsis thaliana that is blocked in the conversion of high-manne to complex glycans. In callus tissues derived from the mutant plants, all glycans bind to concanavalin A. These glycans can be released by treatment with endoglycosidase H, and the majority has the same size as Man[sub 5]GlcNAc[sub 1] glycans. In the presence of deoxymannojirimycin, an inhibitor of mannosidase I, the mutant cells synthesize Man[sub 9]GlcNAc[sub 2] and Man[sub 8]GlcNAc[sub 2] glycans, suggesting that the biochemical lesion in the mutant is not in the biosynthesis of high-mannose glycans in the endoplasmic reticulum but in their modification in the Golgi. Direct enzyme assays of cell extracts show that the mutant cells lack N-acetyl glucosaminyl transferase I, the first enzyme in the pathway of complex glycan biosynthesis. The mutant plants are able to complete their development normally under several environmental conditions, suggesting that complex glycans are not essential for normal developmental processes. By crossing the complex-glycan-deficient strain of A. thaliana with a transgenic strain that expresses the glycoprotein phytohemagglutinin, a unique strain was obtained that synthesizes phytohemagglutinin with two high-mannose glycans, instead of one high-mannose and one complex glycan. 42 refs., 8 figs., 1 tab.

  12. Glucose-6-phosphate dehydrogenase deficiency and sulfadimidin acetylation phenotypes in Egyptian oases.

    PubMed

    Hussein, L; Yamamah, G; Saleh, A

    1992-04-01

    Screening of 1315 males from two Egyptian oases for glucose-6-phosphate dehydrogenase deficiency (G-6PD) found an incidence of 5.9%. The rate of acetylation of sulfadimidin was also studied, and a bimodal distribution was found with 73% rapid acetylators. There is a correlation between high frequency of G-6PD deficiency and high frequency of slow acetylation rate.

  13. Human acetylator polymorphism: estimate of allele frequency in Libya and details of global distribution.

    PubMed Central

    Karim, A K; Elfellah, M S; Evans, D A

    1981-01-01

    Acetylator phenotyping by means of a sulphadimidine tests revealed 65% of Libyan Arabs to be slow acetylators. Hence the frequency of the allele controlling slow acetylation (As) is estimated as q = 0.81 +/- 0.05. This estimate is similar to those previously recorded in European and adjacent Middle Eastern populations. PMID:7328611

  14. Alcohol fuels

    SciTech Connect

    Not Available

    1990-07-01

    Ethanol is an alcohol made from grain that can be blended with gasoline to extend petroleum supplies and to increase gasoline octane levels. Congressional proposals to encourage greater use of alternative fuels could increase the demand for ethanol. This report evaluates the growth potential of the ethanol industry to meet future demand increases and the impacts increased production would have on American agriculture and the federal budget. It is found that ethanol production could double or triple in the next eight years, and that American farmers could provide the corn for this production increase. While corn growers would benefit, other agricultural segments would not; soybean producers, for example could suffer for increased corn oil production (an ethanol byproduct) and cattle ranchers would be faced with higher feed costs because of higher corn prices. Poultry farmers might benefit from lower priced feed. Overall, net farm cash income should increase, and consumers would see slightly higher food prices. Federal budget impacts would include a reduction in federal farm program outlays by an annual average of between $930 million (for double current production of ethanol) to $1.421 billion (for triple production) during the eight-year growth period. However, due to an partial tax exemption for ethanol blended fuels, federal fuel tax revenues could decrease by between $442 million and $813 million.

  15. The Acetyl Group Buffering Action of Carnitine Acetyltransferase Offsets Macronutrient-induced Lysine Acetylation of Mitochondrial Proteins

    PubMed Central

    Davies, Michael N.; Kjalarsdottir, Lilja; Thompson, J. Will; Dubois, Laura G.; Stevens, Robert D.; Ilkayeva, Olga R.; Brosnan, M. Julia; Rolph, Timothy P.; Grimsrud, Paul A.; Muoio, Deborah M.

    2016-01-01

    Lysine acetylation (AcK), a posttranslational modification wherein a two-carbon acetyl group binds covalently to a lysine residue, occurs prominently on mitochondrial proteins and has been linked to metabolic dysfunction. An emergent theory suggests mitochondrial AcK occurs via mass action rather than targeted catalysis. To test this hypothesis we performed mass spectrometry-based acetylproteomic analyses of quadriceps muscles from mice with skeletal muscle-specific deficiency of carnitine acetyltransferase (CrAT), an enzyme that buffers the mitochondrial acetyl-CoA pool by converting short-chain acyl-CoAs to their membrane permeant acylcarnitine counterparts. CrAT deficiency increased tissue acetyl-CoA levels and susceptibility to diet-induced AcK of broad-ranging mitochondrial proteins, coincident with diminished whole body glucose control. Sub-compartment acetylproteome analyses of muscles from obese mice and humans showed remarkable overrepresentation of mitochondrial matrix proteins. These findings reveal roles for CrAT and L-carnitine in modulating the muscle acetylproteome and provide strong experimental evidence favoring the nonenzymatic carbon pressure model of mitochondrial AcK. PMID:26748706

  16. Increased 4-hydroxynonenal protein adducts in male GSTA4–4/PPAR-alpha double knockout mice enhance injury during early stages of alcoholic liver disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To test the significance of lipid peroxidation in the development of alcoholic liver injury, an ethanol (EtOH) liquid diet was fed to male wild type 129/SvJ mice, and glutathione S-transferase A4-4 null (GSTA4-/-) mice for 40 d. GSTA4-/- mice were also crossed with peroxisome proliferator-activated ...

  17. Alcohol Withdrawal and Cerebellar Mitochondria.

    PubMed

    Jung, Marianna E

    2015-08-01

    Cerebellar disorders trigger the symptoms of movement problems, imbalance, incoordination, and frequent fall. Cerebellar disorders are shown in various CNS illnesses including a drinking disorder called alcoholism. Alcoholism is manifested as an inability to control drinking in spite of adverse consequences. Human and animal studies have shown that cerebellar symptoms persist even after complete abstinence from drinking. In particular, the abrupt termination (ethanol withdrawal) of long-term excessive ethanol consumption has shown to provoke a variety of neuronal and mitochondrial damage to the cerebellum. Upon ethanol withdrawal, excitatory neurotransmitter molecules such as glutamate are overly released in brain areas including cerebellum. This is particularly relevant to the cerebellar neuronal network as glutamate signals are projected to Purkinje neurons through granular cells that are the most populated neuronal type in CNS. This excitatory neuronal signal may be elevated by ethanol withdrawal stress, which promotes an increase in intracellular Ca(2+) level and a decrease in a Ca(2+)-binding protein, both of which result in the excessive entry of Ca(2+) to the mitochondria. Subsequently, mitochondria undergo a prolonged opening of mitochondrial permeability transition pore and the overproduction of harmful free radicals, impeding adenosine triphosphate (ATP)-generating function. This in turn provokes the leakage of mitochondrial molecule cytochrome c to the cytosol, which triggers a cascade of adverse cytosol reactions. Upstream to this pathway, cerebellum under the condition of ethanol withdrawal has shown aberrant gene modifications through altered DNA methylation, histone acetylation, or microRNA expression. Interplay between these events and molecules may result in functional damage to cerebellar mitochondria and consequent neuronal degeneration, thereby contributing to motoric deficit. Mitochondria-targeting research may help develop a powerful new

  18. Alcohol Withdrawal and Cerebellar Mitochondria.

    PubMed

    Jung, Marianna E

    2015-08-01

    Cerebellar disorders trigger the symptoms of movement problems, imbalance, incoordination, and frequent fall. Cerebellar disorders are shown in various CNS illnesses including a drinking disorder called alcoholism. Alcoholism is manifested as an inability to control drinking in spite of adverse consequences. Human and animal studies have shown that cerebellar symptoms persist even after complete abstinence from drinking. In particular, the abrupt termination (ethanol withdrawal) of long-term excessive ethanol consumption has shown to provoke a variety of neuronal and mitochondrial damage to the cerebellum. Upon ethanol withdrawal, excitatory neurotransmitter molecules such as glutamate are overly released in brain areas including cerebellum. This is particularly relevant to the cerebellar neuronal network as glutamate signals are projected to Purkinje neurons through granular cells that are the most populated neuronal type in CNS. This excitatory neuronal signal may be elevated by ethanol withdrawal stress, which promotes an increase in intracellular Ca(2+) level and a decrease in a Ca(2+)-binding protein, both of which result in the excessive entry of Ca(2+) to the mitochondria. Subsequently, mitochondria undergo a prolonged opening of mitochondrial permeability transition pore and the overproduction of harmful free radicals, impeding adenosine triphosphate (ATP)-generating function. This in turn provokes the leakage of mitochondrial molecule cytochrome c to the cytosol, which triggers a cascade of adverse cytosol reactions. Upstream to this pathway, cerebellum under the condition of ethanol withdrawal has shown aberrant gene modifications through altered DNA methylation, histone acetylation, or microRNA expression. Interplay between these events and molecules may result in functional damage to cerebellar mitochondria and consequent neuronal degeneration, thereby contributing to motoric deficit. Mitochondria-targeting research may help develop a powerful new

  19. The determination of tRNALeu recognition nucleotides for Escherichia coli L/F transferase.

    PubMed

    Fung, Angela Wai Shan; Leung, Charles Chung Yun; Fahlman, Richard Peter

    2014-08-01

    Escherichia coli leucyl/phenylalanyl-tRNA protein transferase catalyzes the tRNA-dependent post-translational addition of amino acids onto the N-terminus of a protein polypeptide substrate. Based on biochemical and structural studies, the current tRNA recognition model by L/F transferase involves the identity of the 3' aminoacyl adenosine and the sequence-independent docking of the D-stem of an aminoacyl-tRNA to the positively charged cluster on L/F transferase. However, this model does not explain the isoacceptor preference observed 40 yr ago. Using in vitro-transcribed tRNA and quantitative MALDI-ToF MS enzyme activity assays, we have confirmed that, indeed, there is a strong preference for the most abundant leucyl-tRNA, tRNA(Leu) (anticodon 5'-CAG-3') isoacceptor for L/F transferase activity. We further investigate the molecular mechanism for this preference using hybrid tRNA constructs. We identified two independent sequence elements in the acceptor stem of tRNA(Leu) (CAG)-a G₃:C₇₀ base pair and a set of 4 nt (C₇₂, A₄:U₆₉, C₆₈)-that are important for the optimal binding and catalysis by L/F transferase. This maps a more specific, sequence-dependent tRNA recognition model of L/F transferase than previously proposed.

  20. The determination of tRNALeu recognition nucleotides for Escherichia coli L/F transferase

    PubMed Central

    Fung, Angela Wai Shan; Leung, Charles Chung Yun; Fahlman, Richard Peter

    2014-01-01

    Escherichia coli leucyl/phenylalanyl-tRNA protein transferase catalyzes the tRNA-dependent post-translational addition of amino acids onto the N-terminus of a protein polypeptide substrate. Based on biochemical and structural studies, the current tRNA recognition model by L/F transferase involves the identity of the 3′ aminoacyl adenosine and the sequence-independent docking of the D-stem of an aminoacyl-tRNA to the positively charged cluster on L/F transferase. However, this model does not explain the isoacceptor preference observed 40 yr ago. Using in vitro-transcribed tRNA and quantitative MALDI-ToF MS enzyme activity assays, we have confirmed that, indeed, there is a strong preference for the most abundant leucyl-tRNA, tRNALeu (anticodon 5′-CAG-3′) isoacceptor for L/F transferase activity. We further investigate the molecular mechanism for this preference using hybrid tRNA constructs. We identified two independent sequence elements in the acceptor stem of tRNALeu (CAG)—a G3:C70 base pair and a set of 4 nt (C72, A4:U69, C68)—that are important for the optimal binding and catalysis by L/F transferase. This maps a more specific, sequence-dependent tRNA recognition model of L/F transferase than previously proposed. PMID:24935875

  1. Mechanism for the Inhibition of the Carboxyl-transferase

    SciTech Connect

    L Yu; Y Kim; L Tong

    2011-12-31

    Acetyl-CoA carboxylases (ACCs) are crucial metabolic enzymes and have been targeted for drug development against obesity, diabetes, and other diseases. The carboxyltransferase (CT) domain of this enzyme is the site of action for three different classes of herbicides, as represented by haloxyfop, tepraloxydim, and pinoxaden. Our earlier studies have demonstrated that haloxyfop and tepraloxydim bind in the CT active site at the interface of its dimer. However, the two compounds probe distinct regions of the dimer interface, sharing primarily only two common anchoring points of interaction with the enzyme. We report here the crystal structure of the CT domain of yeast ACC in complex with pinoxaden at 2.8-{angstrom} resolution. Despite their chemical diversity, pinoxaden has a similar binding mode as tepraloxydim and requires a small conformational change in the dimer interface for binding. Crystal structures of the CT domain in complex with all three classes of herbicides confirm the importance of the two anchoring points for herbicide binding. The structures also provide a foundation for understanding the molecular basis of the herbicide resistance mutations and cross resistance among the herbicides, as well as for the design and development of new inhibitors against plant and human ACCs.

  2. Suppression of PPARγ-mediated monoacylglycerol O-acyltransferase 1 expression ameliorates alcoholic hepatic steatosis.

    PubMed

    Yu, Jung Hwan; Song, Su Jin; Kim, Ara; Choi, Yoonjeong; Seok, Jo Woon; Kim, Hyo Jung; Lee, Yoo Jeong; Lee, Kwan Sik; Kim, Jae-Woo

    2016-01-01

    Alcohol consumption is one of the major causes of hepatic steatosis, fibrosis, cirrhosis, and superimposed hepatocellular carcinoma. Ethanol metabolism alters the NAD(+)/NADH ratio, thereby suppressing the activity of sirtuin family proteins, which may affect lipid metabolism in liver cells. However, it is not clear how long-term ingestion of ethanol eventually causes lipid accumulation in liver. Here, we demonstrate that chronic ethanol ingestion activates peroxisome proliferator-activated receptor γ (PPARγ) and its target gene, monoacylglycerol O-acyltransferase 1 (MGAT1). During ethanol metabolism, a low NAD(+)/NADH ratio repressed NAD-dependent deacetylase sirtuin 1 (SIRT1) activity, concomitantly resulting in increased acetylated PPARγ with high transcriptional activity. Accordingly, SIRT1 transgenic mice exhibited a low level of acetylated PPARγ and were protected from hepatic steatosis driven by alcohol or PPARγ2 overexpression, suggesting that ethanol metabolism causes lipid accumulation through activation of PPARγ through acetylation. Among the genes induced by PPARγ upon alcohol consumption, MGAT1 has been shown to be involved in triglyceride synthesis. Thus, we tested the effect of MGAT1 knockdown in mice following ethanol consumption, and found a significant reduction in alcohol-induced hepatic lipid accumulation. These results suggest that MGAT1 may afford a promising approach to the treatment of fatty liver disease. PMID:27404390

  3. Suppression of PPARγ-mediated monoacylglycerol O-acyltransferase 1 expression ameliorates alcoholic hepatic steatosis

    PubMed Central

    Yu, Jung Hwan; Song, Su Jin; Kim, Ara; Choi, Yoonjeong; Seok, Jo Woon; Kim, Hyo Jung; Lee, Yoo Jeong; Lee, Kwan Sik; Kim, Jae-woo

    2016-01-01

    Alcohol consumption is one of the major causes of hepatic steatosis, fibrosis, cirrhosis, and superimposed hepatocellular carcinoma. Ethanol metabolism alters the NAD+/NADH ratio, thereby suppressing the activity of sirtuin family proteins, which may affect lipid metabolism in liver cells. However, it is not clear how long-term ingestion of ethanol eventually causes lipid accumulation in liver. Here, we demonstrate that chronic ethanol ingestion activates peroxisome proliferator-activated receptor γ (PPARγ) and its target gene, monoacylglycerol O-acyltransferase 1 (MGAT1). During ethanol metabolism, a low NAD+/NADH ratio repressed NAD-dependent deacetylase sirtuin 1 (SIRT1) activity, concomitantly resulting in increased acetylated PPARγ with high transcriptional activity. Accordingly, SIRT1 transgenic mice exhibited a low level of acetylated PPARγ and were protected from hepatic steatosis driven by alcohol or PPARγ2 overexpression, suggesting that ethanol metabolism causes lipid accumulation through activation of PPARγ through acetylation. Among the genes induced by PPARγ upon alcohol consumption, MGAT1 has been shown to be involved in triglyceride synthesis. Thus, we tested the effect of MGAT1 knockdown in mice following ethanol consumption, and found a significant reduction in alcohol-induced hepatic lipid accumulation. These results suggest that MGAT1 may afford a promising approach to the treatment of fatty liver disease. PMID:27404390

  4. Altered acetylation and succinylation profiles in Corynebacterium glutamicum in response to conditions inducing glutamate overproduction.

    PubMed

    Mizuno, Yuta; Nagano-Shoji, Megumi; Kubo, Shosei; Kawamura, Yumi; Yoshida, Ayako; Kawasaki, Hisashi; Nishiyama, Makoto; Yoshida, Minoru; Kosono, Saori

    2016-02-01

    The bacterium Corynebacterium glutamicum is utilized during industrial fermentation to produce amino acids such as L-glutamate. During L-glutamate fermentation, C. glutamicum changes the flux of central carbon metabolism to favor L-glutamate production, but the molecular mechanisms that explain these flux changes remain largely unknown. Here, we found that the profiles of two major lysine acyl modifications were significantly altered upon glutamate overproduction in C. glutamicum; acetylation decreased, whereas succinylation increased. A label-free semi-quantitative proteomic analysis identified 604 acetylated proteins with 1328 unique acetylation sites and 288 succinylated proteins with 651 unique succinylation sites. Acetylation and succinylation targeted enzymes in central carbon metabolic pathways that are directly related to glutamate production, including the 2-oxoglutarate dehydrogenase complex (ODHC), a key enzyme regulating glutamate overproduction. Structural mapping revealed that several critical lysine residues in the ODHC components were susceptible to acetylation and succinylation. Furthermore, induction of glutamate production was associated with changes in the extent of acetylation and succinylation of lysine, suggesting that these modifications may affect the activity of enzymes involved in glutamate production. Deletion of phosphotransacetylase decreased the extent of protein acetylation in nonproducing condition, suggesting that acetyl phosphate-dependent acetylation is active in C. glutamicum. However, no effect was observed on the profiles of acetylation and succinylation in glutamate-producing condition upon disruption of acetyl phosphate metabolism or deacetylase homologs. It was considered likely that the reduced acetylation in glutamate-producing condition may reflect metabolic states where the flux through acid-producing pathways is very low, and substrates for acetylation do not accumulate in the cell. Succinylation would occur more

  5. Alcoholic hepatitis.

    PubMed

    Damgaard Sandahl, Thomas

    2014-10-01

    Alcoholic hepatitis (AH) is an acute inflammatory syndrome causing significant morbidity and mortality. The prognosis is strongly dependent on disease severity, as assessed by clinical scoring systems. Reliable epidemiological data as well as knowledge of the clinical course of AH are essential for planning and resource allocation within the health care system. Likewise, individual evaluation of risk is desirable in the clinical handling of patients with AH as it can guide treatment, improve patient information, and serve as strata in clinical trials. The present PhD thesis is based on three studies using a cohort of nearly 2000 patients diagnosed with AH in Denmark from 1999 to 2008 as a cohort, in a population-based study design. The aims of this thesis were as follows. (1) To describe the incidence and short- and long-term mortality, of AH in Denmark (Study I). (2) To validate and compare the ability of the currently available prognostic scores to predict mortality in AH (Study II). (3) To investigate the short- and long-term causes of death of patients with AH (Study III). During the study decade, the annual incidence rate in the Danish population rose from 37 to 46 per 106 for men and from 24 to 34 per 106 for women. Both short- and long-term mortality rose for men and women, and the increase in short-term mortality was attributable to increasing patient age and prevalence of cirrhosis. Our evaluation of the most commonly used prognostic scores for predicting the mortality of patients with AH showed that all scores performed similarly, with Area under the Receiver Operator Characteristics curves giving values between 0.74 and 0.78 for 28-day mortality assessed on admission. Our study on causes of death showed that in the short-term (< 84 days after diagnosis), patients with AH were likely to die from liver-related events and infections. In the long-term (≥ 84 days after diagnosis), those who developed cirrhosis mainly died from liver-related causes, and

  6. Selection of antisense oligodeoxynucleotides against glutathione S-transferase Mu.

    PubMed Central

    't Hoen, Peter A C; Out, Ruud; Commandeur, Jan N M; Vermeulen, Nico P E; van Batenburg, F H D; Manoharan, Muthiah; van Berkel, Theo J C; Biessen, Erik A L; Bijsterbosch, Martin K

    2002-01-01

    The aim of the present study was to identify functional antisense oligodeoxynucleotides (ODNs) against the rat glutathione S-transferase Mu (GSTM) isoforms, GSTM1 and GSTM2. These antisense ODNs would enable the study of the physiological consequences of GSTM deficiency. Because it has been suggested that the effectiveness of antisense ODNs is dependent on the secondary mRNA structures of their target sites, we made mRNA secondary structure predictions with two software packages, Mfold and STAR. The two programs produced only marginally similar structures, which can probably be attributed to differences in the algorithms used. The effectiveness of a set of 18 antisense ODNs was evaluated with a cell-free transcription/translation assay, and their activity was correlated with the predicted secondary RNA structures. Four phosphodiester ODNs specific for GSTM1, two ODNs specific for GSTM2, and four ODNs targeted at both GSTM isoforms were found to be potent, sequence-specific, and RNase H-dependent inhibitors of protein expression. The IC50 value of the most potent ODN was approximately 100 nM. Antisense ODNs targeted against regions that were predicted by STAR to be predominantly single stranded were more potent than antisense ODNs against double-stranded regions. Such a correlation was not found for the Mfold prediction. Our data suggest that simulation of the local folding of RNA facilitates the discovery of potent antisense sequences. In conclusion, we selected several promising antisense sequences, which, when synthesized as biologically stable oligonucleotides, can be applied for study of the physiological impact of reduced GSTM expression. PMID:12515389

  7. Glutathione transferase classes alpha, pi, and mu: GSH activation mechanism.

    PubMed

    Dourado, Daniel F A R; Fernandes, Pedro Alexandrino; Ramos, Maria João

    2010-10-14

    Since the early 1960s, glutathione transferases (GSTs) have been described as detoxification enzymes. In fact, GSTs are the most important enzymes involved in the metabolism of electrophilic xenobiotic/endobiotic compounds. These enzymes are able to catalyze the nucleophilic addition of glutathione (GSH) sulfur thiolate to a wide range of electrophilic substrates, building up a less toxic and more soluble compound. Cytosolic classes alpha, pi, and mu are the most extensively studied GSTs. However, many of the catalytic events are still poorly understood. In the present work, we have resorted to density functional theory (DFT) and to potential of mean force (PMF) calculations to determine the GSH activation mechanism of GSTP1-1 and GSTM1-1 isoenzymes. For the GSTP1-1 enzyme, we have demonstrated that a water molecule, after an initial conformational rearrangement of GSH, can assist a proton transfer between the GSH cysteine thiol (GSH-SH) and the GSH glutamate alpha carboxylate (GSH-COO(-)) groups. The energy barrier associated with the proton transfer is 11.36 kcal·mol(-1). The GSTM1-1 enzyme shows a completely different behavior from the previous isoenzyme. In this case, two water molecules, positioned between the GSH-SH and the ξ N atom of His107, working like a bridge, are able to promote the proton transfer between these two active groups with an energy barrier of 7.98 kcal·mol(-1). All our results are consistent with all the enzymes kinetics and mutagenesis experimental studies.

  8. Expression of mung bean pectin acetyl esterase in potato tubers: effect on acetylation of cell wall polymers and tuber mechanical properties.

    PubMed

    Orfila, Caroline; Dal Degan, Florence; Jørgensen, Bodil; Scheller, Henrik Vibe; Ray, Peter M; Ulvskov, Peter

    2012-07-01

    A mung bean (Vigna radiata) pectin acetyl esterase (CAA67728) was heterologously expressed in tubers of potato (Solanum tuberosum) under the control of the granule-bound starch synthase promoter or the patatin promoter in order to probe the significance of O-acetylation on cell wall and tissue properties. The recombinant tubers showed no apparent macroscopic phenotype. The enzyme was recovered from transgenic tubers using a high ionic strength buffer and the extract was active against a range of pectic substrates. Partial in vivo de-acetylation of cell wall polysaccharides occurred in the transformants, as shown by a 39% decrease in the degree of acetylation (DA) of tuber cell wall material (CWM). Treatment of CWM using a combination of endo-polygalacturonase and pectin methyl esterase extracted more pectin polymers from the transformed tissue compared to wild type. The largest effect of the pectin acetyl esterase (68% decrease in DA) was seen in the residue from this extraction, suggesting that the enzyme is preferentially active on acetylated pectin that is tightly bound to the cell wall. The effects of acetylation on tuber mechanical properties were investigated by tests of failure under compression and by determination of viscoelastic relaxation spectra. These tests suggested that de-acetylation resulted in a stiffer tuber tissue and a stronger cell wall matrix, as a result of changes to a rapidly relaxing viscoelastic component. These results are discussed in relation to the role of pectin acetylation in primary cell walls and its implications for industrial uses of potato fibres.

  9. Alcoholism and alcohol drinking habits predicted from alcohol dehydrogenase genes.

    PubMed

    Tolstrup, Janne Schurmann; Nordestgaard, Børge Grønne; Rasmussen, Søren; Tybjaerg-Hansen, Anne; Grønbaek, Morten

    2008-06-01

    Alcohol drinking habits and alcoholism are partly genetically determined. Alcohol is degraded primarily by alcohol dehydrogenase (ADH) wherein genetic variation that affects the rate of alcohol degradation is found in ADH1B and ADH1C. It is biologically plausible that these variations may be associated with alcohol drinking habits and alcoholism. By genotyping 9080 white men and women from the general population, we found that men and women with ADH1B slow vs fast alcohol degradation drank more alcohol and had a higher risk of everyday drinking, heavy drinking, excessive drinking and of alcoholism. For example, the weekly alcohol intake was 9.8 drinks (95% confidence interval (CI): 9.1-11) among men with the ADH1B.1/1 genotype compared to 7.5 drinks (95% CI: 6.4-8.7) among men with the ADH1B.1/2 genotype, and the odds ratio (OR) for heavy drinking was 3.1 (95% CI: 1.7-5.7) among men with the ADH1B.1/1 genotype compared to men with the ADH1B.1/2 genotype. Furthermore, individuals with ADH1C slow vs fast alcohol degradation had a higher risk of heavy and excessive drinking. For example, the OR for heavy drinking was 1.4 (95% CI: 1.1-1.8) among men with the ADH1C.1/2 genotype and 1.4 (95% CI: 1.0-1.9) among men with the ADH1B.2/2 genotype, compared with men with the ADH1C.1/1 genotype. Results for ADH1B and ADH1C genotypes among men and women were similar. Finally, because slow ADH1B alcohol degradation is found in more than 90% of the white population compared to less than 10% of East Asians, the population attributable risk of heavy drinking and alcoholism by ADH1B.1/1 genotype was 67 and 62% among the white population compared with 9 and 24% among the East Asian population.

  10. Astrocyte Reactivity Following Blast Exposure Involves Aberrant Histone Acetylation

    PubMed Central

    Bailey, Zachary S.; Grinter, Michael B.; VandeVord, Pamela J.

    2016-01-01

    Blast induced neurotrauma (BINT) is a prevalent injury within military and civilian populations. The injury is characterized by persistent inflammation at the cellular level which manifests as a multitude of cognitive and functional impairments. Epigenetic regulation of transcription offers an important control mechanism for gene expression and cellular function which may underlie chronic inflammation and result in neurodegeneration. We hypothesize that altered histone acetylation patterns may be involved in blast induced inflammation and the chronic activation of glial cells. This study aimed to elucidate changes to histone acetylation occurring following injury and the roles these changes may have within the pathology. Sprague Dawley rats were subjected to either a 10 or 17 psi blast overpressure within an Advanced Blast Simulator (ABS). Sham animals underwent the same procedures without blast exposure. Memory impairments were measured using the Novel Object Recognition (NOR) test at 2 and 7 days post-injury. Tissues were collected at 7 days for Western blot and immunohistochemistry (IHC) analysis. Sham animals showed intact memory at each time point. The novel object discrimination decreased significantly between two and 7 days for each injury group (p < 0.05). This is indicative of the onset of memory impairment. Western blot analysis showed glial fibrillary acidic protein (GFAP), a known marker of activated astrocytes, was elevated in the prefrontal cortex (PFC) following blast exposure for both injury groups. Analysis of histone protein extract showed no changes in the level of any total histone proteins within the PFC. However, acetylation levels of histone H2b, H3, and H4 were decreased in both groups (p < 0.05). Co-localization immunofluorescence was used to further investigate any potential correlation between decreased histone acetylation and astrocyte activation. These experiments showed a similar decrease in H3 acetylation in astrocytes exposed to a 17

  11. Astrocyte Reactivity Following Blast Exposure Involves Aberrant Histone Acetylation.

    PubMed

    Bailey, Zachary S; Grinter, Michael B; VandeVord, Pamela J

    2016-01-01

    Blast induced neurotrauma (BINT) is a prevalent injury within military and civilian populations. The injury is characterized by persistent inflammation at the cellular level which manifests as a multitude of cognitive and functional impairments. Epigenetic regulation of transcription offers an important control mechanism for gene expression and cellular function which may underlie chronic inflammation and result in neurodegeneration. We hypothesize that altered histone acetylation patterns may be involved in blast induced inflammation and the chronic activation of glial cells. This study aimed to elucidate changes to histone acetylation occurring following injury and the roles these changes may have within the pathology. Sprague Dawley rats were subjected to either a 10 or 17 psi blast overpressure within an Advanced Blast Simulator (ABS). Sham animals underwent the same procedures without blast exposure. Memory impairments were measured using the Novel Object Recognition (NOR) test at 2 and 7 days post-injury. Tissues were collected at 7 days for Western blot and immunohistochemistry (IHC) analysis. Sham animals showed intact memory at each time point. The novel object discrimination decreased significantly between two and 7 days for each injury group (p < 0.05). This is indicative of the onset of memory impairment. Western blot analysis showed glial fibrillary acidic protein (GFAP), a known marker of activated astrocytes, was elevated in the prefrontal cortex (PFC) following blast exposure for both injury groups. Analysis of histone protein extract showed no changes in the level of any total histone proteins within the PFC. However, acetylation levels of histone H2b, H3, and H4 were decreased in both groups (p < 0.05). Co-localization immunofluorescence was used to further investigate any potential correlation between decreased histone acetylation and astrocyte activation. These experiments showed a similar decrease in H3 acetylation in astrocytes exposed to a 17

  12. Perillyl Alcohol (Monoterpene Alcohol), Limonene.

    PubMed

    Shojaei, Shahla; Kiumarsi, Amir; Moghadam, Adel Rezaei; Alizadeh, Javad; Marzban, Hassan; Ghavami, Saeid

    2014-01-01

    Natural products have a long history of use in traditional medicines and their activities against different diseases have been the focus of many basic and clinical researches in past few decades. The essential oils, volatile liquid containing aroma compound from plants, are known as active ingredients in the herbal medicine. Perillyl alcohol (POH) is usually available through dietary sources and is being explored for its cancer chemoprevention, tumor growth suppression, and regression. Citrus peels are the waste product of juice manufacturing industries and have been considered as a critical problem for environmental green ecology policies for years. One of the most well-known approaches to overcome this problem is transformation of these monoterpene by the use of specific strains of bacteria or yeasts. Limonene (1-methyl-4-isopropyl-cyclohexene) is a monoterpene, as other monoterpenes consists of two isoprene units, that comprises more than 90% of citrus essential oil and it exists in many fruits and vegetables. Although, the anticancer activity of d-limonene has identified nearly two decades ago, it has recently attracted much more attention in translational medicine. In this chapter, we will overview the anticancer effects of POH and d-limonene. Later, we will address the pharmacokinetics of these compounds, highlight the signaling pathways which are targeted by these proteins, review the clinical trials which have been done for these compounds in different cancer models, and finally discuss the future directions of the research in this field that might be more applicable in future cancer therapy strategies.

  13. Perillyl Alcohol (Monoterpene Alcohol), Limonene.

    PubMed

    Shojaei, Shahla; Kiumarsi, Amir; Moghadam, Adel Rezaei; Alizadeh, Javad; Marzban, Hassan; Ghavami, Saeid

    2014-01-01

    Natural products have a long history of use in traditional medicines and their activities against different diseases have been the focus of many basic and clinical researches in past few decades. The essential oils, volatile liquid containing aroma compound from plants, are known as active ingredients in the herbal medicine. Perillyl alcohol (POH) is usually available through dietary sources and is being explored for its cancer chemoprevention, tumor growth suppression, and regression. Citrus peels are the waste product of juice manufacturing industries and have been considered as a critical problem for environmental green ecology policies for years. One of the most well-known approaches to overcome this problem is transformation of these monoterpene by the use of specific strains of bacteria or yeasts. Limonene (1-methyl-4-isopropyl-cyclohexene) is a monoterpene, as other monoterpenes consists of two isoprene units, that comprises more than 90% of citrus essential oil and it exists in many fruits and vegetables. Although, the anticancer activity of d-limonene has identified nearly two decades ago, it has recently attracted much more attention in translational medicine. In this chapter, we will overview the anticancer effects of POH and d-limonene. Later, we will address the pharmacokinetics of these compounds, highlight the signaling pathways which are targeted by these proteins, review the clinical trials which have been done for these compounds in different cancer models, and finally discuss the future directions of the research in this field that might be more applicable in future cancer therapy strategies. PMID:27102697

  14. The inhibition of protein prenyltransferases by oxygenated metabolites of limonene and perillyl alcohol.

    PubMed

    Gelb, M H; Tamanoi, F; Yokoyama, K; Ghomashchi, F; Esson, K; Gould, M N

    1995-05-01

    The monoterpenes limonene and perillyl alcohol are effective therapeutic agents against advanced rat mammary cancer. Limonene is currently undergoing clinical testing in cancer patients. These monoterpenes and their oxygenated metabolites have been previously shown to inhibit protein prenylation in cultured cells. Since farnesylation of ras protein is critical for its ability to cause oncogenic transformation, inhibition of protein prenylation may be the basis of the anti-tumor effects of limonene and perillyl alcohol. In this study we test the ability of limonene and its oxygenated analogs to inhibit protein prenylation enzymes in vitro. Limonene and perillyl alcohol and their major in vivo metabolite, perillic acid, are weak inhibitors of both mammalian and yeast protein farnesyl transferase (PFT) and protein geranylgeranyl transferase (PGGT). In contrast, a minor metabolite of both limonene and perillyl alcohol, perillic acid methyl ester, is a potent inhibitor of both enzymes. Perillic acid methyl ester is a competitive inhibitor of yeast PFT with respect to farnesyl pyrophosphate. These studies suggest that if the inhibition of protein prenylation is a mechanism for limonene's and perillyl alcohol's anti-cancer activities, these monoterpenes may be prodrugs that are converted into pharmacologically-active substances by metabolic modification.

  15. The Altered Hepatic Tubulin Code in Alcoholic Liver Disease

    PubMed Central

    Groebner, Jennifer L.; Tuma, Pamela L.

    2015-01-01

    The molecular mechanisms that lead to the progression of alcoholic liver disease have been actively examined for decades. Because the hepatic microtubule cytoskeleton supports innumerable cellular processes, it has been the focus of many such mechanistic studies. It has long been appreciated that α-tubulin is a major target for modification by highly reactive ethanol metabolites and reactive oxygen species. It is also now apparent that alcohol exposure induces post-translational modifications that are part of the natural repertoire, mainly acetylation. In this review, the modifications of the “tubulin code” are described as well as those adducts by ethanol metabolites. The potential cellular consequences of microtubule modification are described with a focus on alcohol-induced defects in protein trafficking and enhanced steatosis. Possible mechanisms that can explain hepatic dysfunction are described and how this relates to the onset of liver injury is discussed. Finally, we propose that agents that alter the cellular acetylation state may represent a novel therapeutic strategy for treating liver disease. PMID:26393662

  16. Multiple Mass Isotopomer Tracing of Acetyl-CoA Metabolism in Langendorff-perfused Rat Hearts

    PubMed Central

    Li, Qingling; Deng, Shuang; Ibarra, Rafael A.; Anderson, Vernon E.; Brunengraber, Henri; Zhang, Guo-Fang

    2015-01-01

    We developed an isotopic technique to assess mitochondrial acetyl-CoA turnover (≈citric acid flux) in perfused rat hearts. Hearts are perfused with buffer containing tracer [13C2,2H3]acetate, which forms M5 + M4 + M3 acetyl-CoA. The buffer may also contain one or two labeled substrates, which generate M2 acetyl-CoA (e.g. [13C6]glucose or [1,2-13C2]palmitate) or/and M1 acetyl-CoA (e.g. [1-13C]octanoate). The total acetyl-CoA turnover and the contributions of fuels to acetyl-CoA are calculated from the uptake of the acetate tracer and the mass isotopomer distribution of acetyl-CoA. The method was applied to measurements of acetyl-CoA turnover under different conditions (glucose ± palmitate ± insulin ± dichloroacetate). The data revealed (i) substrate cycling between glycogen and glucose-6-P and between glucose-6-P and triose phosphates, (ii) the release of small excess acetyl groups as acetylcarnitine and ketone bodies, and (iii) the channeling of mitochondrial acetyl-CoA from pyruvate dehydrogenase to carnitine acetyltransferase. Because of this channeling, the labeling of acetylcarnitine and ketone bodies released by the heart are not proxies of the labeling of mitochondrial acetyl-CoA. PMID:25645937

  17. Stoichiometry of site-specific lysine acetylation in an entire proteome.

    PubMed

    Baeza, Josue; Dowell, James A; Smallegan, Michael J; Fan, Jing; Amador-Noguez, Daniel; Khan, Zia; Denu, John M

    2014-08-01

    Acetylation of lysine ϵ-amino groups influences many cellular processes and has been mapped to thousands of sites across many organisms. Stoichiometric information of acetylation is essential to accurately interpret biological significance. Here, we developed and employed a novel method for directly quantifying stoichiometry of site-specific acetylation in the entire proteome of Escherichia coli. By coupling isotopic labeling and a novel pairing algorithm, our approach performs an in silico enrichment of acetyl peptides, circumventing the need for immunoenrichment. We investigated the function of the sole NAD(+)-dependent protein deacetylase, CobB, on both site-specific and global acetylation. We quantified 2206 peptides from 899 proteins and observed a wide distribution of acetyl stoichiometry, ranging from less than 1% up to 98%. Bioinformatic analysis revealed that metabolic enzymes, which either utilize or generate acetyl-CoA, and proteins involved in transcriptional and translational processes displayed the highest degree of acetylation. Loss of CobB led to increased global acetylation at low stoichiometry sites and induced site-specific changes at high stoichiometry sites, and biochemical analysis revealed altered acetyl-CoA metabolism. Thus, this study demonstrates that sirtuin deacetylase deficiency leads to both site-specific and global changes in protein acetylation stoichiometry, affecting central metabolism.

  18. Neurologic effects of alcoholism.

    PubMed Central

    Diamond, I; Messing, R O

    1994-01-01

    Alcoholism, a worldwide disorder, is the cause of a variety of neurologic disorders. In this article we discuss the cellular pathophysiology of ethanol addition and abuse as well as evidence supporting and refuting the role of inheritance in alcoholism. A genetic marker for alcoholism has not been identified, but neurophysiologic studies may be promising. Some neurologic disorders related to longterm alcoholism are due predominantly to inadequate nutrition (the thiamine deficiency that causes Wernicke's encephalopathy), but others appear to involve the neurotoxicity of ethanol on brain (alcohol withdrawal syndrome and dementia) and peripheral nerves (alcoholic neuropathy and myopathy). Images PMID:7975567

  19. [Effect of acetylation and oxidation on some properties of breadfruit (Artocarpus altilis) seed starch].

    PubMed

    Rincón, Alicia Mariela; Bou Rached, Lizet; Aragoza, Luis E; Padilla, Fanny

    2007-09-01

    Starch extracted from seeds of Artocarpus altilis (Breadfruit) was chemically modified by acetylation and oxidation, and its functional properties were evaluated and compared with these of native starch. Analysis of the chemical composition showed that moisture content was higher for modified starches. Ash, protein, crude fiber and amylose contents were reduced by the modifications, but did not alter the native starch granules' irregularity, oval shape and smooth surface. Acetylation produced changes in water absorption, swelling power and soluble solids, these values were higher for acetylated starch, while values for native and oxidized starches were similar. Both modifications reduced pasting temperature; oxidation reduced maximum peak viscosity but it was increased by acetylation. Hot paste viscosity was reduced by both modifications, whereas cold paste viscosity was lower in the oxidized starch and higher in the acetylated starch. Breakdown was increased by acetylation and reduced with oxidation. Setback value was reduced after acetylation, indicating it could minimize retrogradation of the starch.

  20. N-Terminal Acetylation Acts as an Avidity Enhancer Within an Interconnected Multiprotein Complex

    SciTech Connect

    Scott, Daniel C.; Monda, Julie K.; Bennett, Eric J.; Harper, J. Wade; Schulman, Brenda A.

    2012-10-25

    Although many eukaryotic proteins are amino (N)-terminally acetylated, structural mechanisms by which N-terminal acetylation mediates protein interactions are largely unknown. Here, we found that N-terminal acetylation of the E2 enzyme, Ubc12, dictates distinctive E3-dependent ligation of the ubiquitin-like protein Nedd8 to Cul1. Structural, biochemical, biophysical, and genetic analyses revealed how complete burial of Ubc12's N-acetyl-methionine in a hydrophobic pocket in the E3, Dcn1, promotes cullin neddylation. The results suggest that the N-terminal acetyl both directs Ubc12's interactions with Dcn1 and prevents repulsion of a charged N terminus. Our data provide a link between acetylation and ubiquitin-like protein conjugation and define a mechanism for N-terminal acetylation-dependent recognition.

  1. Histone acetylation dependent energy landscapes in tri-nucleosome revealed by residue-resolved molecular simulations

    PubMed Central

    Chang, Le; Takada, Shoji

    2016-01-01

    Histone tail acetylation is a key epigenetic marker that tends to open chromatin folding and activate transcription. Despite intensive studies, precise roles of individual lysine acetylation in chromatin folding have only been poorly understood. Here, we revealed structural dynamics of tri-nucleosomes with several histone tail acetylation states and analyzed histone tail interactions with DNA by performing molecular simulations at an unprecedentedly high resolution. We found versatile acetylation-dependent landscapes of tri-nucleosome. The H4 and H2A tail acetylation reduced the contact between the first and third nucleosomes mediated by the histone tails. The H3 tail acetylation reduced its interaction with neighboring linker DNAs resulting in increase of the distance between consecutive nucleosomes. Notably, two copies of the same histone in a single nucleosome have markedly asymmetric interactions with DNAs, suggesting specific pattern of nucleosome docking albeit high inherent flexibility. Estimated transcription factor accessibility was significantly high for the H4 tail acetylated structures. PMID:27698366

  2. Fusarium moniliforme extract fed before a single dose of diethylnitrosamine increases the numbers of placental glutathione S-transferase positive hepatocytes in rat liver

    SciTech Connect

    Lebepe, S.; Hendrich, S. )

    1991-03-11

    The carcinogenic potential of an alcohol:water (1:1) extract of Fusarium moniliforme (FUSX), containing 20 ppm fumonisin B{sub 1} was assayed. Groups of six 5-week-old female F344/N rats were fed a semipurified diet, with and without FUSX. A dose of initiating agent, diethylnitrosamine, was given orally. Placental glutathione S-transferase-positive (PGST(+)) hepatocytes were detected by immunohistochemistry and counted on 5 frozen hepatic sections/rat, as an endpoint to assess early stages of carcinogenesis. FUSX had significant co-initiating activity. Fusarium moniliforme infection of feed has been shown to promote hepatocarcinogenesis, and may pose a cocarcinogenic risk even during short-term, low-level exposure.

  3. Dietary Patterns and Serum Gamma-Glutamyl Transferase in Japanese Men and Women

    PubMed Central

    Nanri, Hinako; Hara, Megumi; Nishida, Yuichiro; Shimanoe, Chisato; Nakamura, Kazuyo; Higaki, Yasuki; Imaizumi, Takeshi; Taguchi, Naoto; Sakamoto, Tatsuhiko; Horita, Mikako; Shinchi, Koichi; Kokaze, Akatsuki; Tanaka, Keitaro

    2015-01-01

    Background Although specific foods and nutrients have been examined as potential determinants of serum gamma-glutamyl transferase (GGT) concentrations, the relationship between dietary patterns and GGT remains unknown. The present cross-sectional study aimed to determine relationships between dietary patterns and GGT concentrations, and the effects of lifestyle factors on GGT. Methods Relationships between dietary patterns and GGT were analyzed in 9803 Japanese individuals (3723 men and 6080 women age 40–69 years) without a history of liver diseases or elevated serum aminotransferase. We examined major dietary patterns by factor analysis of 46 items determined from a validated, short food frequency questionnaire. Results We defined dietary patterns as healthy, Western, seafood, bread, and dessert. The healthy pattern was inversely related to GGT in men (odds ratio [OR] for highest vs lowest quartile, 0.72; 95% confidence interval [CI], 0.57–0.92; P < 0.01 for trend) and women (OR 0.82; 95% CI, 0.66–1.0; P = 0.05 for trend), whereas the seafood pattern was positively related to GGT in men (OR 1.27; 95% CI, 1.01–1.61; P = 0.03 for trend) and women (OR 1.21; 95% CI, 0.98–1.49; P = 0.05 for trend). Male-specific inverse associations with GGT were found for bread and dessert patterns (OR 0.63; 95% CI, 0.50–0.80 and OR 0.53; 95% CI, 0.41–0.68, respectively; P < 0.01 for both trends). Seafood or bread patterns and alcohol consumption significantly interacted with GGT in men (P = 0.03 and <0.01 for interaction, respectively) and between the dessert pattern and body mass index or smoking habit in women (P = 0.03 and <0.01, respectively, for interaction). Conclusions Dietary patterns may be important determinants of GGT, and their possible clinical implications warrant further investigation. PMID:25787241

  4. Givinostat inhibition of hepatic stellate cell proliferation and protein acetylation

    PubMed Central

    Wang, Yu-Gang; Xu, Ling; Wang, Ting; Wei, Jue; Meng, Wen-Ying; Wang, Na; Shi, Min

    2015-01-01

    AIM: To explore the effect of the histone deacetylase inhibitor givinostat on proteins related to regulation of hepatic stellate cell proliferation. METHODS: The cell counting kit-8 assay and flow cytometry were used to observe changes in proliferation, apoptosis, and cell cycle in hepatic stellate cells treated with givinostat. Western blot was used to observe expression changes in p21, p57, CDK4, CDK6, cyclinD1, caspase-3, and caspase-9 in hepatic stellate cells exposed to givinostat. The scratch assay was used to analyze the effect of givinostat on cell migration. Effects of givinostat on the reactive oxygen species profile, mitochondrial membrane potential, and mitochondrial permeability transition pore opening in JS-1 cells were observed by laser confocal microscopy. RESULTS: Givinostat significantly inhibited JS-1 cell proliferation and promoted cell apoptosis, leading to cell cycle arrest in G0/G1 phases. Treatment with givinostat downregulated protein expression of CDK4, CDK6, and cyclin D1, whereas expression of p21 and p57 was significantly increased. The givinostat-induced apoptosis of hepatic stellate cells was mainly mediated through p38 and extracellular signal-regulated kinase 1/2. Givinostat treatment increased intracellular reactive oxygen species production, decreased mitochondrial membrane potential, and promoted mitochondrial permeability transition pore opening. Acetylation of superoxide dismutase (acetyl K68) and nuclear factor-κB p65 (acetyl K310) was upregulated, while there was no change in protein expression. Moreover, the notable beneficial effect of givinostat on liver fibrosis was also confirmed in the mouse models. CONCLUSION: Givinostat has antifibrotic activities via regulating the acetylation of nuclear factor-κB and superoxide dismutase 2, thus inhibiting hepatic stellate cell proliferation and inducing apoptosis. PMID:26217084

  5. Mechanism of action of clostridial glycine reductase: Isolation and characterization of a covalent acetyl enzyme intermediate

    SciTech Connect

    Arkowitz, R.A.; Abeles, R.H. )

    1991-04-23

    Clostridial glycine reductase consists of proteins A, B, and C and catalyzes the reaction glycine + P{sub i} + 2e{sup {minus}} {yields} acetyl phosphate + NH{sub 4}{sup +}. Evidence was previously obtained that is consistent with the involvement of an acyl enzyme intermediate in this reaction. The authors now demonstrate that protein C catalyzes exchange of ({sup 32}P)P{sub i} into acetyl phosphate, providing additional support for an acetyl enzyme intermediate on protein C. Furthermore, they have isolated acetyl protein C and shown that it is qualitatively, catalytically competent. Acetyl protein C can be obtained through the forward reaction from protein C and Se-(carboxymethyl)selenocysteine-protein A, which is generated by the reaction of glycine with proteins A and B. Acetyl protein C can also be generated through the reverse reaction by the addition of acetyl phosphate to protein C. Both procedures lead to the same acetyl enzyme. The acetyl enzyme reacts with P{sub i} to give acetyl phosphate. When ({sup 14}C)acetyl protein C is denaturated with TCA and redissolved with urea, radioactivity remained associated with the protein. Treatment with KBH{sub 4} removes all the radioactivity associated with protein C, resulting in the formation of ({sup 14}C)ethanol. They conclude that a thiol group on protein C is acetylated. Proteins A and C together catalyze the exchange of tritium atoms from ({sup 3}H)H{sub 2}O into acetyl phosphate. This exchange reaction supports the proposal that an enol of the acetyl enzyme is an intermediate in the reaction sequence.

  6. N-Acetyl-4-aminophenol (paracetamol), N-acetyl-2-aminophenol and acetanilide in urine samples from the general population, individuals exposed to aniline and paracetamol users.

    PubMed

    Dierkes, Georg; Weiss, Tobias; Modick, Hendrik; Käfferlein, Heiko Udo; Brüning, Thomas; Koch, Holger M

    2014-01-01

    Epidemiological studies suggest associations between the use of N-acetyl-4-aminophenol (paracetamol) during pregnancy and increased risks of reproductive disorders in the male offspring. Previously we have reported a ubiquitous urinary excretion of N-acetyl-4-aminophenol in the general population. Possible sources are (1) direct intake of paracetamol through medication, (2) paracetamol residues in the food chain and (3) environmental exposure to aniline or related substances that are metabolized into N-acetyl-4-aminophenol. In order to elucidate the origins of the excretion of N-acetyl-4-aminophenol in urine and to contribute to the understanding of paracetamol and aniline metabolism in humans we developed a rapid, turbulent-flow HPLC-MS/MS method with isotope dilution for the simultaneous quantification of N-acetyl-4-aminophenol and two other aniline related metabolites, N-acetyl-2-aminophenol and acetanilide. We applied this method to three sets of urine samples: (1) individuals with no known exposure to aniline and also no recent paracetamol medication; (2) individuals after occupational exposure to aniline but no paracetamol medication and (3) paracetamol users. We confirmed the omnipresent excretion of N-acetyl-4-aminophenol. Additionally we revealed an omnipresent excretion of N-acetyl-2-aminophenol. In contrast, acetanilide was only found after occupational exposure to aniline, not in the general population or after paracetamol use. The results lead to four preliminary conclusions: (1) other sources than aniline seem to be responsible for the major part of urinary N-acetyl-4-aminophenol in the general population; (2) acetanilide is a metabolite of aniline in man and a valuable biomarker for aniline in occupational settings; (3) aniline baseline levels in the general population measured after chemical hydrolysis do not seem to originate from acetanilide and hence not from a direct exposure to aniline itself and (4) N-acetyl-2-aminophenol does not seem to be

  7. N-Acetyl-4-aminophenol (paracetamol), N-acetyl-2-aminophenol and acetanilide in urine samples from the general population, individuals exposed to aniline and paracetamol users.

    PubMed

    Dierkes, Georg; Weiss, Tobias; Modick, Hendrik; Käfferlein, Heiko Udo; Brüning, Thomas; Koch, Holger M

    2014-01-01

    Epidemiological studies suggest associations between the use of N-acetyl-4-aminophenol (paracetamol) during pregnancy and increased risks of reproductive disorders in the male offspring. Previously we have reported a ubiquitous urinary excretion of N-acetyl-4-aminophenol in the general population. Possible sources are (1) direct intake of paracetamol through medication, (2) paracetamol residues in the food chain and (3) environmental exposure to aniline or related substances that are metabolized into N-acetyl-4-aminophenol. In order to elucidate the origins of the excretion of N-acetyl-4-aminophenol in urine and to contribute to the understanding of paracetamol and aniline metabolism in humans we developed a rapid, turbulent-flow HPLC-MS/MS method with isotope dilution for the simultaneous quantification of N-acetyl-4-aminophenol and two other aniline related metabolites, N-acetyl-2-aminophenol and acetanilide. We applied this method to three sets of urine samples: (1) individuals with no known exposure to aniline and also no recent paracetamol medication; (2) individuals after occupational exposure to aniline but no paracetamol medication and (3) paracetamol users. We confirmed the omnipresent excretion of N-acetyl-4-aminophenol. Additionally we revealed an omnipresent excretion of N-acetyl-2-aminophenol. In contrast, acetanilide was only found after occupational exposure to aniline, not in the general population or after paracetamol use. The results lead to four preliminary conclusions: (1) other sources than aniline seem to be responsible for the major part of urinary N-acetyl-4-aminophenol in the general population; (2) acetanilide is a metabolite of aniline in man and a valuable biomarker for aniline in occupational settings; (3) aniline baseline levels in the general population measured after chemical hydrolysis do not seem to originate from acetanilide and hence not from a direct exposure to aniline itself and (4) N-acetyl-2-aminophenol does not seem to be

  8. Fetal Alcohol Spectrum Disorders.

    PubMed

    Williams, Janet F; Smith, Vincent C

    2015-11-01

    Prenatal exposure to alcohol can damage the developing fetus and is the leading preventable cause of birth defects and intellectual and neurodevelopmental disabilities. In 1973, fetal alcohol syndrome was first described as a specific cluster of birth defects resulting from alcohol exposure in utero. Subsequently, research unequivocally revealed that prenatal alcohol exposure causes a broad range of adverse developmental effects. Fetal alcohol spectrum disorder (FASD) is the general term that encompasses the range of adverse effects associated with prenatal alcohol exposure. The diagnostic criteria for fetal alcohol syndrome are specific, and comprehensive efforts are ongoing to establish definitive criteria for diagnosing the other FASDs. A large and growing body of research has led to evidence-based FASD education of professionals and the public, broader prevention initiatives, and recommended treatment approaches based on the following premises:▪ Alcohol-related birth defects and developmental disabilities are completely preventable when pregnant women abstain from alcohol use.▪ Neurocognitive and behavioral problems resulting from prenatal alcohol exposure are lifelong.▪ Early recognition, diagnosis, and therapy for any condition along the FASD continuum can result in improved outcomes.▪ During pregnancy:◦no amount of alcohol intake should be considered safe;◦there is no safe trimester to drink alcohol;◦all forms of alcohol, such as beer, wine, and liquor, pose similar risk; and◦binge drinking poses dose-related risk to the developing fetus.

  9. Fetal Alcohol Spectrum Disorders.

    PubMed

    Williams, Janet F; Smith, Vincent C

    2015-11-01

    Prenatal exposure to alcohol can damage the developing fetus and is the leading preventable cause of birth defects and intellectual and neurodevelopmental disabilities. In 1973, fetal alcohol syndrome was first described as a specific cluster of birth defects resulting from alcohol exposure in utero. Subsequently, research unequivocally revealed that prenatal alcohol exposure causes a broad range of adverse developmental effects. Fetal alcohol spectrum disorder (FASD) is the general term that encompasses the range of adverse effects associated with prenatal alcohol exposure. The diagnostic criteria for fetal alcohol syndrome are specific, and comprehensive efforts are ongoing to establish definitive criteria for diagnosing the other FASDs. A large and growing body of research has led to evidence-based FASD education of professionals and the public, broader prevention initiatives, and recommended treatment approaches based on the following premises:▪ Alcohol-related birth defects and developmental disabilities are completely preventable when pregnant women abstain from alcohol use.▪ Neurocognitive and behavioral problems resulting from prenatal alcohol exposure are lifelong.▪ Early recognition, diagnosis, and therapy for any condition along the FASD continuum can result in improved outcomes.▪ During pregnancy:◦no amount of alcohol intake should be considered safe;◦there is no safe trimester to drink alcohol;◦all forms of alcohol, such as beer, wine, and liquor, pose similar risk; and◦binge drinking poses dose-related risk to the developing fetus. PMID:26482673

  10. Acetylation modification regulates GRP78 secretion in colon cancer cells.

    PubMed

    Li, Zongwei; Zhuang, Ming; Zhang, Lichao; Zheng, Xingnan; Yang, Peng; Li, Zhuoyu

    2016-01-01

    High glucose-regulated protein 78 (GRP78) expression contributes to the acquisition of a wide range of phenotypic cancer hallmarks, and the pleiotropic oncogenic functions of GRP78 may result from its diverse subcellular distribution. Interestingly, GRP78 has been reported to be secreted from solid tumour cells, participating in cell-cell communication in the tumour microenvironment. However, the mechanism underlying this secretion remains elusive. Here, we report that GRP78 is secreted from colon cancer cells via exosomes. Histone deacetylase (HDAC) inhibitors blocked GRP78 release by inducing its aggregation in the ER. Mechanistically, HDAC inhibitor treatment suppressed HDAC6 activity and led to increased GRP78 acetylation; acetylated GRP78 then bound to VPS34, a class III phosphoinositide-3 kinase, consequently preventing the sorting of GRP78 into multivesicular bodies (MVBs). Of note, we found that mimicking GRP78 acetylation by substituting the lysine at residue 633, one of the deacetylated sites of HDAC6, with a glutamine resulted in decreased GRP78 secretion and impaired tumour cell growth in vitro. Our study thus reveals a hitherto-unknown mechanism of GRP78 secretion and may also provide implications for the therapeutic use of HDAC inhibitors. PMID:27460191

  11. Carbon isotope fractionation and the acetyl-CoA pathway

    NASA Astrophysics Data System (ADS)

    Blaser, Martin; Conrad, Ralf

    2010-05-01

    Homoacetogenic bacteria can catalyze the reductive synthesis of acetate from CO2 via the acetyl-CoA pathway. Besides this unifying property homoacetogenic bacteria constitute a metabolically and phylogenetically diverse bacteriological group. Therefore their environmental role is difficult to address. It has been recognized that in methanogenic environments homoacetogenic bacteria contribute to the degradation of organic matter. The natural abundance of 13C may be used to understand the functional impact of homoacetogenic bacteria in the soil environment. To distinguish the acetyl-CoA pathway from other dominant processes, the isotopic composition of acetate and CO2 can be determined and the fractionation factors of the individual processes may be used to discriminate between the dominant pathways. To characterize the fractionation factor associated with the acetyl-CoA pathway the phylogenetic and metabolic diversity needs to be considered. Therefore the fractionation factor of substrate utilization and product formation of different homoacetogens (Acetobacterium woodii, Sporomusa ovata, Thermoanaerobacter kivui, Morella thermoautotrophica) has been studied under pure culture conditions in two defined minimal medium with H2/CO2 as sole source of carbon and energy. It became obvious that the cultivation conditions have a major impact on the obtained fractionation factors.

  12. Acetylation modification regulates GRP78 secretion in colon cancer cells

    PubMed Central

    Li, Zongwei; Zhuang, Ming; Zhang, Lichao; Zheng, Xingnan; Yang, Peng; Li, Zhuoyu

    2016-01-01

    High glucose-regulated protein 78 (GRP78) expression contributes to the acquisition of a wide range of phenotypic cancer hallmarks, and the pleiotropic oncogenic functions of GRP78 may result from its diverse subcellular distribution. Interestingly, GRP78 has been reported to be secreted from solid tumour cells, participating in cell-cell communication in the tumour microenvironment. However, the mechanism underlying this secretion remains elusive. Here, we report that GRP78 is secreted from colon cancer cells via exosomes. Histone deacetylase (HDAC) inhibitors blocked GRP78 release by inducing its aggregation in the ER. Mechanistically, HDAC inhibitor treatment suppressed HDAC6 activity and led to increased GRP78 acetylation; acetylated GRP78 then bound to VPS34, a class III phosphoinositide-3 kinase, consequently preventing the sorting of GRP78 into multivesicular bodies (MVBs). Of note, we found that mimicking GRP78 acetylation by substituting the lysine at residue 633, one of the deacetylated sites of HDAC6, with a glutamine resulted in decreased GRP78 secretion and impaired tumour cell growth in vitro. Our study thus reveals a hitherto-unknown mechanism of GRP78 secretion and may also provide implications for the therapeutic use of HDAC inhibitors. PMID:27460191

  13. Investigation of acetylated chitosan microspheres as potential chemoembolic agents.

    PubMed

    Zhou, Xuan; Kong, Ming; Cheng, Xiaojie; Li, Jingjing; Li, Jing; Chen, Xiguang

    2014-11-01

    The aim was to investigate the potential of chitosan microspheres (CMs) with different acetylation using as a chemoembolic agent. Chitosan microspheres (CMs) were prepared via water-in-oil (W/O) emulsification cross-linking method, and acetylated chitosan microspheres (ACMs) were obtained by acetylation of CMs. Next, we characterized the morphology, size, composition and degrees of deacetylation using scanning electron microscopy (TEM), dynamic laser light scattering (DLS), and Fourier transform infrared spectrometer (FTIR). All microspheres had smooth surfaces and good mechanical flexibility, and all could pass through a 5F catheter. The swelling rate (SR) of CMs decreased significantly with the increase of pH (4.0-10.0) but ACMs did not change under the same conditions. Protein absorption assays suggested that albumin was more greatly adsorbed on CMs than on ACMs. Furthermore, CMs caused more blood clots than ACMs. ACMs caused hemolysis less than CMs (<5% of the time). Data indicated that ACMs had more hemocompatibility. Cytotoxicity tests indicated that ACMs initially had less cell attached proliferation but increased with incubation. In contrast, the relative growth rate of mouse embryo fibroblasts (MEFs) on CMs decreased gradually. The results suggested that ACMs could stimulate the growth of MEFs, and CMs were not cytotoxic to MEFs. Thus, ACMs were more biocompatible with greater potential to be used as chemoembolic material.

  14. Characterization of glutathione-S-transferases in zebrafish (Danio rerio).

    PubMed

    Glisic, Branka; Mihaljevic, Ivan; Popovic, Marta; Zaja, Roko; Loncar, Jovica; Fent, Karl; Kovacevic, Radmila; Smital, Tvrtko

    2015-01-01

    Glutathione-S-transferases (GSTs) are one of the key enzymes that mediate phase II of cellular detoxification. The aim of our study was a comprehensive characterization of GSTs in zebrafish (Danio rerio) as an important vertebrate model species frequently used in environmental research. A detailed phylogenetic analysis of GST superfamily revealed 27 zebrafish gst genes. Further insights into the orthology relationships between human and zebrafish GSTs/Gsts were obtained by the conserved synteny analysis. Expression of gst genes in six tissues (liver, kidney, gills, intestine, brain and gonads) of adult male and female zebrafish was determined using qRT-PCR. Functional characterization was performed on 9 cytosolic Gst enzymes after overexpression in E. coli and subsequent protein purification. Enzyme kinetics was measured for GSH and a series of model substrates. Our data revealed ubiquitously high expression of gstp, gstm (except in liver), gstr1, mgst3a and mgst3b, high expression of gsto2 in gills and ovaries, gsta in intestine and testes, gstt1a in liver, and gstz1 in liver, kidney and brain. All zebrafish Gsts catalyzed the conjugation of GSH to model GST substrates 1-chloro-2,4-dinitrobenzene (CDNB) and monochlorobimane (MCB), apart from Gsto2 and Gstz1 that catalyzed GSH conjugation to dehydroascorbate (DHA) and dichloroacetic acid (DCA), respectively. Affinity toward CDNB varied from 0.28 mM (Gstp2) to 3.69 mM (Gstm3), while affinity toward MCB was in the range of 5 μM (Gstt1a) to 250 μM (Gstp1). Affinity toward GSH varied from 0.27 mM (Gstz1) to 4.45 mM (Gstt1a). Turnover number for CDNB varied from 5.25s(-1) (Gstt1a) to 112s(-1) (Gstp2). Only Gst Pi enzymes utilized ethacrynic acid (ETA). We suggest that Gstp1, Gstp2, Gstt1a, Gstz1, Gstr1, Mgst3a and Mgst3b have important role in the biotransformation of xenobiotics, while Gst Alpha, Mu, Pi, Zeta and Rho classes are involved in the crucial physiological processes. In summary, this study provides the

  15. Unusual metal ion catalysis in an acyl-transferase ribozyme.

    PubMed

    Suga, H; Cowan, J A; Szostak, J W

    1998-07-14

    Most studies of the roles of catalytic metal ions in ribozymes have focused on inner-sphere coordination of the divalent metal ions to the substrate or ribozyme. However, divalent metal ions are strongly hydrated in water, and some proteinenzymes, such as Escherichia coli RNase H and exonuclease III, are known to use metal cofactors in their fully hydrated form [Duffy, T. H., and Nowak, T. (1985) Biochemistry 24, 1152-1160; Jou, R., and Cowan, J. A. (1991) J. Am. Chem. Soc. 113, 6685-6686]. It is therefore important to consider the possibility of outer-sphere coordination of catalytic metal ions in ribozymes. We have used an exchange-inert metal complex, cobalt hexaammine, to show that the catalytic metal ion in an acyl-transferase ribozyme acts through outer-sphere coordination. Our studies provide an example of a fully hydrated Mg2+ ion that plays an essential role in ribozyme catalysis. Kinetic studies of wild-type and mutant ribozymes suggest that a pair of tandem G:U wobble base pairs adjacent to the reactive center constitute the metal-binding site. This result is consistent with recent crystallographic studies [Cate, J. H., and Doudna, J. A. (1996) Structure 4, 1221-1229; Cate, J. H., Gooding, A. R., Podell, E., Zhou, K., Golden, B. L., Kundrot, C. E., Cech, T. R., and Doudna, J. A. (1996) Science 273, 1678-1685; Cate, J. H., Hanna, R. L., and Doudna, J. A. (1997) Nat. Struct. Biol. 4, 553-558] showing that tandem wobble base pairs are good binding sites for metal hexaammines. We propose a model in which the catalytic metal ion is bound in the major groove of the tandem wobble base pairs, is precisely positioned by the ribozyme within the active site, and stabilizes the developing oxyanion in the transition state. Our results may have significant implications for understanding the mechanism of protein synthesis [Noller, H. F., Hoffarth, V., and Zimniak, L. (1992) Science 256, 1416-1419].

  16. Alcohol Use and Older Adults

    MedlinePlus

    ... version of this page please turn Javascript on. Alcohol Use and Older Adults Alcohol and Aging Adults of any age can have ... Escape (Esc) button on your keyboard.) What Is Alcohol? Alcohol, also known as ethanol, is a chemical ...

  17. Alcohol and Cancer Risk

    MedlinePlus

    ... Overview Cancer Prevention Overview–for health professionals Research Alcohol and Cancer Risk On This Page What is ... in the risk of colorectal cancer. Research on alcohol consumption and other cancers: Numerous studies have examined ...

  18. Alcohol and Migraine

    MedlinePlus

    ... on Pinterest Follow us on Instagram DONATE TODAY Alcohol and Migraine Abuse, Maltreatment, and PTSD and Their ... to Migraine Altitude, Acute Mountain Sickness and Headache Alcohol and Migraine Anxiety and Depression Caffeine and Migraine ...

  19. Benzyl Alcohol Topical

    MedlinePlus

    Benzyl alcohol lotion is used to treat head lice (small insects that attach themselves to the skin) in adults ... children less than 6 months of age. Benzyl alcohol is in a class of medications called pediculicides. ...

  20. Translational Studies of Alcoholism

    PubMed Central

    Zahr, Natalie M.; Sullivan, Edith V.

    2008-01-01

    Human studies are necessary to identify and classify the brain systems predisposing individuals to develop alcohol use disorders and those modified by alcohol, while animal models of alcoholism are essential for a mechanistic understanding of how chronic voluntary alcohol consumption becomes compulsive, how brain systems become damaged, and how damage resolves. Our current knowledge of the neuroscience of alcohol dependence has evolved from the interchange of information gathered from both human alcoholics and animal models of alcoholism. Together, studies in humans and animal models have provided support for the involvement of specific brain structures over the course of alcohol addiction, including the prefrontal cortex, basal ganglia, cerebellum, amygdala, hippocampus, and the hypothalamic–pituitary–adrenal axis. PMID:20041042

  1. [Neurologic sequelae of alcohol].

    PubMed

    Ladurner, G; Griebnitz, E

    1986-10-10

    The consequences of alcoholism on the peripheral and central nervous system are discussed. Polyneuropathy is present in 30% of the alcoholics, whilst cranial nerve involvement is found in 5-25%. Alcoholic myopathy is only very rarely seen. Wernicke's encephalopathy is found at post mortem investigation in 1.8% of alcoholics, but is rarely clinically diagnosed. The Marchiafava-Bignamy syndrome and central pontine myelinolysis are rarely seen; alcoholic amblyopia which is seen in 0.5% of the hospitalised alcoholics is more frequent, but still a rare finding. Cerebral seizures are common in chronic alcoholics with an incidence varying from 5 to 37% according to the type of drinking habit and have, thus, to be categorised. Brain atrophy is a common finding and correlates with the duration and extent of the alcoholism. PMID:3788182

  2. Alcohol and Cancer

    MedlinePlus

    ... developing some kinds of cancer. The way alcohol causes cancer isn’t completely understood. In fact, there might ... For example, it could be that alcohol itself causes cancer by increasing hormone levels, or it may be ...

  3. Alcohol Calorie Calculator

    MedlinePlus

    ... Alcohol Calorie Calculator Find out the number of beer and hard alcohol calories you are consuming. Simply ... calories) Average Drinks Per Week Monthly Subtotal Calories Beer Regular 12 149 Regular Beer Light 12 110 ...

  4. National Institute on Alcohol Abuse and Alcoholism

    MedlinePlus

    ... TODAY: “Neurodevelopment and Alcohol: From Cell Adhesion to Cell Phones" Dr. Michael Charness, 11/3 @3 , Masur t. ... lecture: “Neurodevelopment and Alcohol: From Cell Adhesion to Cell Phones" Dr. Michael Charness, 11/3 @3 pm, Masur ...

  5. Crystal structure of tabtoxin resistance protein complexed with acetyl coenzyme A reveals the mechanism for {beta}-lactam acetylation.

    SciTech Connect

    He, H.; Ding, Y.; Bartlam, M.; Sun, F.; Le, Y.; Qin, X.; Tang, H.; Zhang, R.; Joachimiak, A.; Liu, J.; Zhao, N.; Rao, Z.; Biosciences Division; Tsinghua Univ.; Chinese Academy of Science

    2003-01-31

    Tabtoxin resistance protein (TTR) is an enzyme that renders tabtoxin-producing pathogens, such as Pseudomonas syringae, tolerant to their own phytotoxins. Here, we report the crystal structure of TTR complexed with its natural cofactor, acetyl coenzyme A (AcCoA), to 1.55 {angstrom} resolution. The binary complex forms a characteristic 'V' shape for substrate binding and contains the four motifs conserved in the GCN5-related N-acetyltransferase (GNAT) superfamily, which also includes the histone acetyltransferases (HATs). A single-step mechanism is proposed to explain the function of three conserved residues, Glu92, Asp130 and Tyr141, in catalyzing the acetyl group transfer to its substrate. We also report that TTR possesses HAT activity and suggest an evolutionary relationship between TTR and other GNAT members.

  6. Glyceryl trinitrate metabolism in the quail embryo by the glutathione S-transferases leads to a perturbation in redox status and embryotoxicity.

    PubMed

    Bardai, Ghalib K; Hales, Barbara F; Sunahara, Geoffrey I

    2013-07-01

    Exposure of stage 9 quail (Coturnix coturnix japonica) embryos to glyceryl trinitrate (GTN) induces malformations that were associated in previous studies with an increase in protein nitration. Increased nitration suggests metabolism of GTN by the embryo. The goals of this study were to characterize the enzymes and co-factors required for GTN metabolism by quail embryos, and to determine the effects of in ovo treatment with N-acetyl cysteine (NAC), a precursor of glutathione (GSH), on GTN embryotoxicity. GTN treatment of quail embryos resulted in an increase in nitrite, a decrease in total GSH, and an increase in the ratio of NADP(+)/NADPH, indicating that redox balance may be compromised in exposed embryos. Glutathione S-transferases (GSTs; EC 2.5.1.18) purified from the whole embryo (K(m) 0.84 mM; V(max) 36 μM/min) and the embryonic eye (K(m) 0.20 mM; V(max) 30 μM/min) had GTN-metabolizing activity (1436 and 34 nmol/min/mg, respectively); the addition of ethacrynic acid, an inhibitor of GST activity, decreased GTN metabolism. Peptide sequencing of the GST isozymes indicated that alpha- or mu-type GSTs in the embryo and embryonic eye had GTN metabolizing activity. NAC co-treatment partially protected against the effects of GTN exposure. Thus, GTN denitration by quail embryo GSTs may represent a key initial step in the developmental toxicity of GTN.

  7. Alcohol and motorcycle fatalities.

    PubMed Central

    Baker, S P; Fisher, R S

    1977-01-01

    A series of 99 fatal motorcycle crashes in Maryland was studied retrospectively, using police and medical examiner records. Blood alcohol concentrations were determined for 62 motorcycle drivers; measurable amounts of alcohol were found in two-thirds (41), and one-half (31) had illegally high concentrations of 100 mg/100 ml or more. The police report mentioned alcohol in only 9 instances. High blood alcohol concentrations were found most commonly among drivers age 20-34. PMID:842762

  8. The Alcoholism Questionnaire.

    ERIC Educational Resources Information Center

    Ferneau, E.; Mueller, S.

    The alcoholism questionnaire used to survey college student attitudes on the subject is provided. It is identical to the drug-abuse questionnaire except for word changes appropriate to the subject matter. The questionnaire consists of 40 statements about alcoholics and alcoholism, with 7 possible responses: (1) completely disagree; (2) mostly…

  9. Youths' Perceptions of Alcoholism.

    ERIC Educational Resources Information Center

    Lorch, Barbara (Day); Hughes, Robert H.

    1986-01-01

    Only a third of students in this study accepted the medical model of alcoholism. Those who had the least knowledge of, and experience with, alcohol were the most likely to consider alcoholism as an illness. The source of information on drugs most conducive to acceptance of the medical model was parents. (Author/ABB)

  10. Alcohol and Minority Youth.

    ERIC Educational Resources Information Center

    Wright, Roosevelt, Jr.; Watts, Thomas D.

    1991-01-01

    Maintains that minority youth who use (or abuse) alcohol in American society deal with using alcohol, being minority, and being young, three dimensions viewed by society with mixed, sometimes hostile and/or fearful reactions. Suggests that examining alcoholism among minority youth involves coming to grips with poverty, education, income, and life…

  11. Television: Alcohol's Vast Adland.

    ERIC Educational Resources Information Center

    2002

    Concern about how much television alcohol advertising reaches underage youth and how the advertising influences their attitudes and decisions about alcohol use has been widespread for many years. Lacking in the policy debate has been solid, reliable information about the extent of youth exposure to television alcohol advertising. To address this…

  12. Alcohol on Campus.

    ERIC Educational Resources Information Center

    ACU-I Bulletin, 1984

    1984-01-01

    Alcohol use on campus and strategies colleges are using to educate students about alcohol are considered in two articles. In "When Alternatives Aren't," Ruth Bradford Burnham and Stephen J. Nelson explore the role alcoholic beverages play in young people's social lives and some of the implications for planning social events. They offer a balanced…

  13. Biological Vulnerability to Alcoholism.

    ERIC Educational Resources Information Center

    Schuckit, Marc A.

    1987-01-01

    Reviews the role of biological factors in the risk for alcoholism. Notes the importance of the definition of primary alcoholism and highlights data indicating that this disorder is genetically influenced. In studies of men at high risk for the future development of alcoholism, vulnerability shows up in reactions to ethanol brain wave amplitude and…

  14. Adult Children of Alcoholics.

    ERIC Educational Resources Information Center

    Goodman, Ronald W.

    1987-01-01

    Presents analysis of adult children of alcoholics, their experience and adjustment in relation to the severity and type of alcoholism, age considerations and perceptions as a child, and existence and nature of significant others. Discusses alcoholics' and others' family issues, focusing on roles taken, and personality characteristics. Emphasizes…

  15. Alcoholism and Lesbians

    ERIC Educational Resources Information Center

    Gedro, Julie

    2014-01-01

    This chapter explores the issues involved in the relationship between lesbianism and alcoholism. It examines the constellation of health and related problems created by alcoholism, and it critically interrogates the societal factors that contribute to the disproportionately high rates of alcoholism among lesbians by exploring the antecedents and…

  16. Alcoholism's Hidden Curriculum.

    ERIC Educational Resources Information Center

    Gress, James R.

    1988-01-01

    Discusses children of alcoholics as victims of fetal alcohol syndrome, family violence, retarded social development, and severe emotional scars. These children bring family roles to school that allow survival in the alcoholic home but are dysfunctional outside it. Educators can take certain steps to address these students' problems. Includes six…

  17. Women and Alcohol

    MedlinePlus

    ... alcohol, which is found in: »» 12 ounces of beer with 5 percent alcohol content »» 5 ounces of wine with 12 percent alcohol content »» 1.5 ounces ... reflect customary serving sizes. A large cup of beer, an overpoured glass of wine, or a single ...

  18. Peptidyl transferase inhibition by the nascent leader peptide of an inducible cat gene.

    PubMed Central

    Gu, Z; Rogers, E J; Lovett, P S

    1993-01-01

    The site of ribosome stalling in the leader of cat transcripts is critical to induction of downstream translation. Site-specific stalling requires translation of the first five leader codons and the presence of chloramphenicol, a sequence-independent inhibitor of ribosome elongation. We demonstrate in this report that a synthetic peptide (the 5-mer) corresponding to the N-terminal five codons of the cat-86 leader inhibits peptidyl transferase in vitro. The N-terminal 2-, 3-, and 4-mers and the reverse 5-mer (reverse amino acid sequence of the 5-mer) are virtually without effect on peptidyl transferase. A missense mutation in the cat-86 leader that abolishes induction in vivo corresponds to an amino acid replacement in the 5-mer that completely relieves peptidyl transferase inhibition. In contrast, a missense mutation that does not interfere with in vivo induction corresponds to an amino acid replacement in the 5-mer that does not significantly alter peptidyl transferase inhibition. Our results suggest that peptidyl transferase inhibition by the nascent cat-86 5-mer peptide may be the primary determinant of the site of ribosome stalling in the leader. A model based on this concept can explain the site specificity of ribosome stalling as well as the response of induction to very low levels of the antibiotic inducer. Images PMID:7690023

  19. Alcohol and the elderly.

    PubMed

    Dufour, M C; Archer, L; Gordis, E

    1992-02-01

    Moderate drinking for the elderly of both genders is no more than one drink per day, where a drink is defined as 12 oz of beer, 5 oz of wine, or 1.5 oz of spirits. Age does not affect the rate of absorption or elimination of alcohol. Lean body mass decreases and adipose tissue increases with age, however, resulting in a corresponding decrease in the volume of total body water. With a smaller volume of distribution, an alcohol dose identical to that administered to a younger individual of the same size and gender will produce a higher blood alcohol concentration in the elderly. Low-dose alcohol stimulates appetite and promoters regular bowel function. In the well-nourished nonalcoholic elderly, the negative impact of alcohol consumption on nutrition is minimal. Alcohol consumption improves mood by increasing feelings of happiness and freedom from care while lessening inhibitions, stress, tension, and depression. Although in the laboratory low-dose alcohol improves certain types of cognitive function in young men, in other types of task performance, alcohol induces impairment, which worsens with age. The effects of alcohol on sleep are primarily detrimental, worsening both insomnia and breathing disturbances during sleep. Although the role of alcohol consumption in mortality from heart disease has not been investigated in the elderly, moderate drinking appears safe. Under some circumstances low-dose alcohol may produce analgesia whereas in others it may worsen pain. The elderly use a significant proportion of both prescription and over-the-counter medication, a large variety of which interact with alcohol. Alcoholic beverage consumption may exacerbate cognitive impairment and dementias of other etiology. Although some studies suggest that moderate use of alcohol by institutionalized senior citizens appears to produce benefits including improved socialization, separation of the effects of the social situation from those specifically attributable to alcohol remains to

  20. Proteome-wide analysis reveals widespread lysine acetylation of major protein complexes in the malaria parasite

    PubMed Central

    Cobbold, Simon A.; Santos, Joana M.; Ochoa, Alejandro; Perlman, David H.; Llinás, Manuel

    2016-01-01

    Lysine acetylation is a ubiquitous post-translational modification in many organisms including the malaria parasite Plasmodium falciparum, yet the full extent of acetylation across the parasite proteome remains unresolved. Moreover, the functional significance of acetylation or how specific acetyl-lysine sites are regulated is largely unknown. Here we report a seven-fold expansion of the known parasite ‘acetylome’, characterizing 2,876 acetylation sites on 1,146 proteins. We observe that lysine acetylation targets a diverse range of protein complexes and is particularly enriched within the Apicomplexan AP2 (ApiAP2) DNA-binding protein family. Using quantitative proteomics we determined that artificial perturbation of the acetate/acetyl-CoA balance alters the acetyl-lysine occupancy of several ApiAP2 DNA-binding proteins and related transcriptional proteins. This metabolic signaling could mediate significant downstream transcriptional responses, as we show that acetylation of an ApiAP2 DNA-binding domain ablates its DNA-binding propensity. Lastly, we investigated the acetyl-lysine targets of each class of lysine deacetylase in order to begin to explore how each class of enzyme contributes to regulating the P. falciparum acetylome. PMID:26813983

  1. Cell differentiation along multiple pathways accompanied by changes in histone acetylation status.

    PubMed

    Legartová, Soňa; Kozubek, Stanislav; Franek, Michal; Zdráhal, Zbyněk; Lochmanová, Gabriela; Martinet, Nadine; Bártová, Eva

    2014-04-01

    Post-translational modification of histones is fundamental to the regulation of basic nuclear processes and subsequent cellular events, including differentiation. In this study, we analyzed acetylated forms of histones H2A, H2B, and H4 during induced differentiation in mouse (mESCs) and human (hESCs) embryonic stem cells and during induced enterocytic differentiation of colon cancer cells in vitro. Endoderm-like differentiation of mESCs induced by retinoic acid and enterocytic differentiation induced by histone deacetylase inhibitor sodium butyrate were accompanied by increased mono-, di-, and tri-acetylation of histone H2B and a pronounced increase in di- and tri-acetylation of histone H4. In enterocytes, mono-acetylation of histone H2A also increased and tetra-acetylation of histone H4 appeared only after induction of this differentiation pathway. During differentiation of hESCs, we observed increased mono-acetylation and decreased tri-acetylation of H2B. Mono-, di-, and tri-acetylation of H4 were reduced, manifested by a significant increase in nonacetylated H4 histones. Levels of acetylated histones increased during induced differentiation in mESCs and during histone deacetylase (HDAC) inhibitor-induced enterocytic differentiation, whereas differentiation of human ESCs was associated with reduced acetylation of histones H2B and H4.

  2. Acetylation of Werner syndrome protein (WRN): relationships with DNA damage, DNA replication and DNA metabolic activities

    PubMed Central

    Lozada, Enerlyn; Yi, Jingjie; Luo, Jianyuan; Orren, David K.

    2014-01-01

    Loss of WRN function causes Werner Syndrome, characterized by increased genomic instability, elevated cancer susceptibility and premature aging. Although WRN is subject to acetylation, phosphorylation and sumoylation, the impact of these modifications on WRN’s DNA metabolic function remains unclear. Here, we examined in further depth the relationship between WRN acetylation and its role in DNA metabolism, particularly in response to induced DNA damage. Our results demonstrate that endogenous WRN is acetylated somewhat under unperturbed conditions. However, levels of acetylated WRN significantly increase after treatment with certain DNA damaging agents or the replication inhibitor hydroxyurea. Use of DNA repair-deficient cells or repair pathway inhibitors further increase levels of acetylated WRN, indicating that induced DNA lesions and their persistence are at least partly responsible for increased acetylation. Notably, acetylation of WRN correlates with inhibition of DNA synthesis, suggesting that replication blockage might underlie this effect. Moreover, WRN acetylation modulates its affinity for and activity on certain DNA structures, in a manner that may enhance its relative specificity for physiological substrates. Our results also show that acetylation and deacetylation of endogenous WRN is a dynamic process, with sirtuins and other histone deacetylases contributing to WRN deacetylation. These findings advance our understanding of the dynamics of WRN acetylation under unperturbed conditions and following DNA damage induction, linking this modification not only to DNA damage persistence but also potentially to replication stalling caused by specific DNA lesions. Our results are consistent with proposed metabolic roles for WRN and genomic instability phenotypes associated with WRN deficiency. PMID:24965941

  3. N-Acetyl-β-D-glucosaminidase activity in feral Carcinus maenas exposed to cadmium.

    PubMed

    Mesquita, Sofia Raquel; Ergen, Şeyda Fikirdeşici; Rodrigues, Aurélie Pinto; Oliva-Teles, M Teresa; Delerue-Matos, Cristina; Guimarães, Laura

    2015-02-01

    Cadmium is a priority hazardous substance, persistent in the aquatic environment, with the capacity to interfere with crustacean moulting. Moulting is a vital process dictating crustacean growth, reproduction and metamorphosis. However, for many organisms, moult disruption is difficult to evaluate in the short term, what limits its inclusion in monitoring programmes. N-acetyl-β-D-glucosaminidase (NAGase) is an enzyme acting in the final steps of the endocrine-regulated moulting cascade, allowing for the cast off of the old exoskeleton, with potential interest as a biomarker of moult disruption. This study investigated responses to waterborne cadmium of NAGase activity of Carcinus maenas originating from estuaries with different histories of anthropogenic contamination: a low impacted and a moderately polluted one. Crabs from both sites were individually exposed for seven days to cadmium concentrations ranging from 1.3 to 2000 μg/L. At the end of the assays, NAGase activity was assessed in the epidermis and digestive gland. Detoxification, antioxidant, energy production, and oxidative stress biomarkers implicated in cadmium metabolism and tolerance were also assessed to better understand differential NAGase responses: activity of glutathione S-transferases (GST), glutathione peroxidase (GPx) glutathione reductase (GR), levels of total glutathiones (TG), lipid peroxidation (LPO), lactate dehydrogenase (LDH), and NADP(+)-dependent isocitrate dehydrogenase (IDH). Animals from the moderately polluted estuary had lower NAGase activity both in the epidermis and digestive gland than in the low impacted site. NAGase activity in the epidermis and digestive gland of C. maenas from both estuaries was sensitive to cadmium exposure suggesting its usefulness for inclusion in monitoring programmes. However, in the digestive gland NAGase inhibition was found in crabs from the less impacted site but not in those from the moderately contaminated one. Altered glutathione levels were

  4. Chronic alcohol binging injures the liver and other organs by reducing NAD⁺ levels required for sirtuin's deacetylase activity.

    PubMed

    French, Samuel W

    2016-04-01

    NAD(+) levels are markedly reduced when blood alcohol levels are high during binge drinking. This causes liver injury to occur because the enzymes that require NAD(+) as a cofactor such as the sirtuin de-acetylases cannot de-acetylate acetylated proteins such as acetylated histones. This prevents the epigenetic changes that regulate metabolic processes and which prevent organ injury such as fatty liver in response to alcohol abuse. Hyper acetylation of numerous regulatory proteins develops. Systemic multi-organ injury occurs when NAD(+) is reduced. For instance the Circadian clock is altered if NAD(+) is not available. Cell cycle arrest occurs due to up regulation of cell cycle inhibitors leading to DNA damage, mutations, apoptosis and tumorigenesis. NAD(+) is linked to aging in the regulation of telomere stability. NAD(+) is required for mitochondrial renewal. Alcohol dehydrogenase is present in every visceral organ in the body so that there is a systemic reduction of NAD(+) levels in all of these organs during binge drinking. PMID:26896648

  5. Chronic alcohol binging injures the liver and other organs by reducing NAD⁺ levels required for sirtuin's deacetylase activity.

    PubMed

    French, Samuel W

    2016-04-01

    NAD(+) levels are markedly reduced when blood alcohol levels are high during binge drinking. This causes liver injury to occur because the enzymes that require NAD(+) as a cofactor such as the sirtuin de-acetylases cannot de-acetylate acetylated proteins such as acetylated histones. This prevents the epigenetic changes that regulate metabolic processes and which prevent organ injury such as fatty liver in response to alcohol abuse. Hyper acetylation of numerous regulatory proteins develops. Systemic multi-organ injury occurs when NAD(+) is reduced. For instance the Circadian clock is altered if NAD(+) is not available. Cell cycle arrest occurs due to up regulation of cell cycle inhibitors leading to DNA damage, mutations, apoptosis and tumorigenesis. NAD(+) is linked to aging in the regulation of telomere stability. NAD(+) is required for mitochondrial renewal. Alcohol dehydrogenase is present in every visceral organ in the body so that there is a systemic reduction of NAD(+) levels in all of these organs during binge drinking.

  6. Structure of succinyl-CoA:3-ketoacid CoA transferase from Drosophila melanogaster

    PubMed Central

    Zhang, Min; Xu, Han-Yang; Wang, Yi-Cui; Shi, Zhu-Bing; Zhang, Nan-Nan

    2013-01-01

    Succinyl-CoA:3-ketoacid CoA transferase (SCOT) plays a crucial role in ketone-body metabolism. SCOT from Drosophila melanogaster (DmSCOT) was purified and crystallized. The crystal structure of DmSCOT was determined at 2.64 Å resolution and belonged to space group P212121, with unit-cell parameters a = 76.638, b = 101.921, c = 122.457 Å, α = β = γ = 90°. Sequence alignment and structural analysis identified DmSCOT as a class I CoA transferase. Compared with Acetobacter aceti succinyl-CoA:acetate CoA transferase, DmSCOT has a different substrate-binding pocket, which may explain the difference in their substrate specificities. PMID:24100554

  7. Alcohol and the Intestine.

    PubMed

    Patel, Sheena; Behara, Rama; Swanson, Garth R; Forsyth, Christopher B; Voigt, Robin M; Keshavarzian, Ali

    2015-01-01

    Alcohol abuse is a significant contributor to the global burden of disease and can lead to tissue damage and organ dysfunction in a subset of alcoholics. However, a subset of alcoholics without any of these predisposing factors can develop alcohol-mediated organ injury. The gastrointestinal tract (GI) could be an important source of inflammation in alcohol-mediated organ damage. The purpose of review was to evaluate mechanisms of alcohol-induced endotoxemia (including dysbiosis and gut leakiness), and highlight the predisposing factors for alcohol-induced dysbiosis and gut leakiness to endotoxins. Barriers, including immunologic, physical, and biochemical can regulate the passage of toxins into the portal and systemic circulation. In addition, a host of environmental interactions including those influenced by circadian rhythms can impact alcohol-induced organ pathology. There appears to be a role for therapeutic measures to mitigate alcohol-induced organ damage by normalizing intestinal dysbiosis and/or improving intestinal barrier integrity. Ultimately, the inflammatory process that drives progression into organ damage from alcohol appears to be multifactorial. Understanding the role of the intestine in the pathogenesis of alcoholic liver disease can pose further avenues for pathogenic and treatment approaches.

  8. Alcohol and the Intestine

    PubMed Central

    Patel, Sheena; Behara, Rama; Swanson, Garth R.; Forsyth, Christopher B.; Voigt, Robin M.; Keshavarzian, Ali

    2015-01-01

    Alcohol abuse is a significant contributor to the global burden of disease and can lead to tissue damage and organ dysfunction in a subset of alcoholics. However, a subset of alcoholics without any of these predisposing factors can develop alcohol-mediated organ injury. The gastrointestinal tract (GI) could be an important source of inflammation in alcohol-mediated organ damage. The purpose of review was to evaluate mechanisms of alcohol-induced endotoxemia (including dysbiosis and gut leakiness), and highlight the predisposing factors for alcohol-induced dysbiosis and gut leakiness to endotoxins. Barriers, including immunologic, physical, and biochemical can regulate the passage of toxins into the portal and systemic circulation. In addition, a host of environmental interactions including those influenced by circadian rhythms can impact alcohol-induced organ pathology. There appears to be a role for therapeutic measures to mitigate alcohol-induced organ damage by normalizing intestinal dysbiosis and/or improving intestinal barrier integrity. Ultimately, the inflammatory process that drives progression into organ damage from alcohol appears to be multifactorial. Understanding the role of the intestine in the pathogenesis of alcoholic liver disease can pose further avenues for pathogenic and treatment approaches. PMID:26501334

  9. Alcohol and the Intestine.

    PubMed

    Patel, Sheena; Behara, Rama; Swanson, Garth R; Forsyth, Christopher B; Voigt, Robin M; Keshavarzian, Ali

    2015-01-01

    Alcohol abuse is a significant contributor to the global burden of disease and can lead to tissue damage and organ dysfunction in a subset of alcoholics. However, a subset of alcoholics without any of these predisposing factors can develop alcohol-mediated organ injury. The gastrointestinal tract (GI) could be an important source of inflammation in alcohol-mediated organ damage. The purpose of review was to evaluate mechanisms of alcohol-induced endotoxemia (including dysbiosis and gut leakiness), and highlight the predisposing factors for alcohol-induced dysbiosis and gut leakiness to endotoxins. Barriers, including immunologic, physical, and biochemical can regulate the passage of toxins into the portal and systemic circulation. In addition, a host of environmental interactions including those influenced by circadian rhythms can impact alcohol-induced organ pathology. There appears to be a role for therapeutic measures to mitigate alcohol-induced organ damage by normalizing intestinal dysbiosis and/or improving intestinal barrier integrity. Ultimately, the inflammatory process that drives progression into organ damage from alcohol appears to be multifactorial. Understanding the role of the intestine in the pathogenesis of alcoholic liver disease can pose further avenues for pathogenic and treatment approaches. PMID:26501334

  10. Genetics and alcoholism.

    PubMed

    Edenberg, Howard J; Foroud, Tatiana

    2013-08-01

    Alcohol is widely consumed; however, excessive use creates serious physical, psychological and social problems and contributes to the pathogenesis of many diseases. Alcohol use disorders (that is, alcohol dependence and alcohol abuse) are maladaptive patterns of excessive drinking that lead to serious problems. Abundant evidence indicates that alcohol dependence (alcoholism) is a complex genetic disease, with variations in a large number of genes affecting a person's risk of alcoholism. Some of these genes have been identified, including two genes involved in the metabolism of alcohol (ADH1B and ALDH2) that have the strongest known affects on the risk of alcoholism. Studies continue to reveal other genes in which variants affect the risk of alcoholism or related traits, including GABRA2, CHRM2, KCNJ6 and AUTS2. As more variants are analysed and studies are combined for meta-analysis to achieve increased sample sizes, an improved picture of the many genes and pathways that affect the risk of alcoholism will be possible.

  11. Alcoholic and non-alcoholic steatohepatitis

    PubMed Central

    Neuman, Manuela G.; French, Samuel W.; French, Barbara A.; Seitz, Helmut K.; Cohen, Lawrence B.; Mueller, Sebastian; Osna, Natalia A.; Kharbanda, Kusum K.; Seth, Devanshi; Bautista, Abraham; Thompson, Kyle J.; McKillop, Iain H.; Kirpich, Irina A.; McClain, Craig J.; Bataller, Ramon; Nanau, Radu M.; Voiculescu, Mihai; Opris, Mihai; Shen, Hong; Tillman, Brittany; Li, Jun; Liu, Hui; Thomas, Paul G.; Ganesan, Murali; Malnick, Steve

    2015-01-01

    This paper is based upon the “Charles Lieber Satellite Symposia” organized by Manuela G. Neuman at the Research Society on Alcoholism (RSA) Annual Meetings, 2013 and 2014. The present review includes pre-clinical, translational and clinical research that characterize alcoholic liver disease (ALD) and non-alcoholic steatohepatitis (NASH). In addition, a literature search in the discussed area was performed. Strong clinical and experimental evidence lead to recognition of the key toxic role of alcohol in the pathogenesis of ALD. The liver biopsy can confirm the etiology of NASH or alcoholic steatohepatitis (ASH) and assess structural alterations of cells, their organelles, as well as inflammatory activity. Three histological stages of ALD are simple steatosis, ASH, and chronic hepatitis with hepatic fibrosis or cirrhosis. These latter stages may also be associated with a number of cellular and histological changes, including the presence of Mallory's hyaline, megamitochondria, or perivenular and perisinusoidal fibrosis. Genetic polymorphisms of ethanol metabolizing enzymes such as cytochrome p450 (CYP) 2E1 activation may change the severity of ASH and NASH. Alcohol mediated hepatocarcinogenesis, immune response to alcohol in ASH, as well as the role of other risk factors such as its comorbidities with chronic viral hepatitis in the presence or absence of human deficiency virus are discussed. Dysregulation of hepatic methylation, as result of ethanol exposure, in hepatocytes transfected with hepatitis C virus (HCV), illustrates an impaired interferon signaling. The hepatotoxic effects of ethanol undermine the contribution of malnutrition to the liver injury. Dietary interventions such as micro and macronutrients, as well as changes to the microbiota are suggested. The clinical aspects of NASH, as part of metabolic syndrome in the aging population, are offered. The integrative symposia investigate different aspects of alcohol-induced liver damage and possible

  12. Alcohol disrupts sleep homeostasis.

    PubMed

    Thakkar, Mahesh M; Sharma, Rishi; Sahota, Pradeep

    2015-06-01

    Alcohol is a potent somnogen and one of the most commonly used "over the counter" sleep aids. In healthy non-alcoholics, acute alcohol decreases sleep latency, consolidates and increases the quality (delta power) and quantity of NREM sleep during the first half of the night. However, sleep is disrupted during the second half. Alcoholics, both during drinking periods and during abstinences, suffer from a multitude of sleep disruptions manifested by profound insomnia, excessive daytime sleepiness, and altered sleep architecture. Furthermore, subjective and objective indicators of sleep disturbances are predictors of relapse. Finally, within the USA, it is estimated that societal costs of alcohol-related sleep disorders exceeds $18 billion. Thus, although alcohol-associated sleep problems have significant economic and clinical consequences, very little is known about how and where alcohol acts to affect sleep. In this review, we have described our attempts to unravel the mechanism of alcohol-induced sleep disruptions. We have conducted a series of experiments using two different species, rats and mice, as animal models. We performed microdialysis, immunohistochemical, pharmacological, sleep deprivation and lesion studies which suggest that the sleep-promoting effects of alcohol may be mediated via alcohol's action on the mediators of sleep homeostasis: adenosine (AD) and the wake-promoting cholinergic neurons of the basal forebrain (BF). Alcohol, via its action on AD uptake, increases extracellular AD resulting in the inhibition of BF wake-promoting neurons. Since binge alcohol consumption is a highly prevalent pattern of alcohol consumption and disrupts sleep, we examined the effects of binge drinking on sleep-wakefulness. Our results suggest that disrupted sleep homeostasis may be the primary cause of sleep disruption observed following binge drinking. Finally, we have also shown that sleep disruptions observed during acute withdrawal, are caused due to impaired

  13. O-acetylated oligosaccharides from pectins of potato tuber cell walls.

    PubMed Central

    Ishii, T

    1997-01-01

    Acetylated trigalacturonides and rhamnogalacturonan I (RG-I)-derived oligosaccharides were isolated from a Driselase digest of potato tuber cell walls by ion-exchange and size-exclusion chromatography. The oligosaccharides were structurally characterized by fast atom bombardment-mass spectroscopy, nuclear magnetic resonance spectroscopy, and glycosyl-linkage composition analysis. One trigalacturonide contained a single acetyl group at O-3 of the reducing galacturonic acid residue. A second trigalacturonide contained two acetyl substituents, which were located on O-3 or O-4 of the nonreducing galacturonic acid residue and O-3 of the reducing galacturonic acid residue. RG-I backbone-derived oligomers had acetyl groups at O-2 of the galacturonic acid residues. Some of these galacturonic acid residues were O-acetylated at both O-2 and O-3 positions. Rhamnosyl residues of RG-I oligomers were not acetylated. PMID:9112775

  14. Transitions in histone acetylation reveal boundaries of three separately regulated neighboring loci

    PubMed Central

    Litt, Michael D.; Simpson, Melanie; Recillas-Targa, Félix; Prioleau, Marie-Noëlle; Felsenfeld, Gary

    2001-01-01

    We have studied developmentally regulated patterns of histone acetylation at high resolution across ∼54 kb of DNA containing three independently regulated but neighboring genetic loci. These include a folate receptor gene, a 16 kb condensed chromatin region, the chicken β-globin domain and an adjacent olfactory receptor gene. Within these regions the relative levels of acetylation appear to fall into three classes. The condensed chromatin region maintains the lowest acetylation at every developmental stage. Genes that are inactive show similarly low levels, but activation results in a dramatic increase in acetylation. The highest levels of acetylation are seen at regulatory sites upstream of the genes. These patterns imply the action of more than one class of acetylation. Notably, there is a very strong constitutive focus of hyperacetylation at the 5′ insulator element separating the globin locus from the folate receptor region, which suggests that this insulator element may harbor a high concentration of histone acetylases. PMID:11331588

  15. Activity Detection of GalNAc Transferases by Protein-Based Fluorescence Sensors In Vivo.

    PubMed

    Song, Lina; Bachert, Collin; Linstedt, Adam D

    2016-01-01

    Mucin-type O-glycosylation occurring in the Golgi apparatus is an important protein posttranslational modification initiated by up to 20 GalNAc-transferase isozymes with largely distinct substrate specificities. Regulation of this enzyme family affects a vast array of proteins transiting the secretory pathway and misregulation causes human diseases. Here we describe the use of protein-based fluorescence sensors that traffic in the secretory pathway to monitor GalNAc-transferase activity in living cells. The sensors can either be "pan" or isozyme specific.

  16. Activity Detection of GalNAc Transferases by Protein-Based Fluorescence Sensors In Vivo.

    PubMed

    Song, Lina; Bachert, Collin; Linstedt, Adam D

    2016-01-01

    Mucin-type O-glycosylation occurring in the Golgi apparatus is an important protein posttranslational modification initiated by up to 20 GalNAc-transferase isozymes with largely distinct substrate specificities. Regulation of this enzyme family affects a vast array of proteins transiting the secretory pathway and misregulation causes human diseases. Here we describe the use of protein-based fluorescence sensors that traffic in the secretory pathway to monitor GalNAc-transferase activity in living cells. The sensors can either be "pan" or isozyme specific. PMID:27632006

  17. Epigenetic Readers of Lysine Acetylation Regulate Cocaine-Induced Plasticity

    PubMed Central

    Sartor, Gregory C.; Powell, Samuel K.; Brothers, Shaun P.

    2015-01-01

    Epigenetic processes that regulate histone acetylation play an essential role in behavioral and molecular responses to cocaine. To date, however, only a small fraction of the mechanisms involved in the addiction-associated acetylome have been investigated. Members of the bromodomain and extraterminal (BET) family of epigenetic “reader” proteins (BRD2, BRD3, BRD4, and BRDT) bind acetylated histones and serve as a scaffold for the recruitment of macromolecular complexes to modify chromatin accessibility and transcriptional activity. The role of BET proteins in cocaine-induced plasticity, however, remains elusive. Here, we used behavioral, pharmacological, and molecular techniques to examine the involvement of BET bromodomains in cocaine reward. Of the BET proteins, BRD4, but not BRD2 or BRD3, was significantly elevated in the nucleus accumbens (NAc) of mice and rats following repeated cocaine injections and self-administration. Systemic and intra-accumbal inhibition of BRD4 with the BET inhibitor, JQ1, attenuated the rewarding effects of cocaine in a conditioned place preference procedure but did not affect conditioned place aversion, nor did JQ1 alone induce conditioned aversion or preference. Investigating the underlying mechanisms, we found that repeated cocaine injections enhanced the binding of BRD4, but not BRD3, to the promoter region of Bdnf in the NAc, whereas systemic injection of JQ1 attenuated cocaine-induced expression of Bdnf in the NAc. JQ1 and siRNA-mediated knockdown of BRD4 in vitro also reduced expression of Bdnf. These findings indicate that disrupting the interaction between BET proteins and their acetylated lysine substrates may provide a new therapeutic avenue for the treatment of drug addiction. SIGNIFICANCE STATEMENT Proteins involved in the “readout” of lysine acetylation marks, referred to as BET bromodomain proteins (including BRD2, BRD3, BRD4, and BRDT), have been shown to be key regulators of chromatin dynamics and disease, and

  18. Kinetic analysis of histone acetylation turnover and Trichostatin A induced hyper- and hypoacetylation in alfalfa.

    PubMed

    Waterborg, Jakob H; Kapros, Tamás

    2002-01-01

    Dynamic histone acetylation is a characteristic of chromatin transcription. The first estimates for the rate of acetylation turnover of plants are reported, measured in alfalfa cells by pulse, pulse-chase, and steady-state acetylation labeling. Acetylation turnover half-lives of about 0.5 h were observed by all methods used for histones H3, H4, and H2B. This is consistent with the rate at which changes in gene expression occur in plants. Treatment with histone deacetylase inhibitor Trichostatin A (TSA) induced hyperacetylation at a similar rate. Replacement histone variant H3.2, preferentially localized in highly acetylated chromatin, displayed faster acetyl turnover. Histone H2A with a low level of acetylation was not subject to rapid turnover or hyperacetylation. Patterns of acetate labeling revealed fundamental differences between histone H3 versus histones H4 and H2B. In H3, acetylation of all molecules, limited by lysine methylation, had similar rates, independent of the level of lysine acetylation. Acetylation of histones H4 and H2B was seen in only a fraction of all molecules and involved multiacetylation. Acetylation turnover rates increased from mono- to penta- and hexaacetylated forms, respectively. TSA was an effective inhibitor of alfalfa histone deacetylases in vivo and caused a doubling in steady-state acetylation levels by 4-6 h after addition. However, hyperacetylation was transient due to loss of TSA inhibition. TSA-induced overexpression of cellular deacetylase activity produced hypoacetylation by 18 h treatment with enhanced acetate turnover labeling of alfalfa histones. Thus, application of TSA to change gene expression in vivo in plants may have unexpected consequences. PMID:12123281

  19. Autoimmune regulator is acetylated by transcription coactivator CBP/p300

    SciTech Connect

    Saare, Mario; Rebane, Ana; Rajashekar, Balaji; Vilo, Jaak; Peterson, Paert

    2012-08-15

    The Autoimmune Regulator (AIRE) is a regulator of transcription in the thymic medulla, where it controls the expression of a large set of peripheral-tissue specific genes. AIRE interacts with the transcriptional coactivator and acetyltransferase CBP and synergistically cooperates with it in transcriptional activation. Here, we aimed to study a possible role of AIRE acetylation in the modulation of its activity. We found that AIRE is acetylated in tissue culture cells and this acetylation is enhanced by overexpression of CBP and the CBP paralog p300. The acetylated lysines were located within nuclear localization signal and SAND domain. AIRE with mutations that mimicked acetylated K243 and K253 in the SAND domain had reduced transactivation activity and accumulated into fewer and larger nuclear bodies, whereas mutations that mimicked the unacetylated lysines were functionally similar to wild-type AIRE. Analogously to CBP, p300 localized to AIRE-containing nuclear bodies, however, the overexpression of p300 did not enhance the transcriptional activation of AIRE-regulated genes. Further studies showed that overexpression of p300 stabilized the AIRE protein. Interestingly, gene expression profiling revealed that AIRE, with mutations mimicking K243/K253 acetylation in SAND, was able to activate gene expression, although the affected genes were different and the activation level was lower from those regulated by wild-type AIRE. Our results suggest that the AIRE acetylation can influence the selection of AIRE activated genes. -- Highlights: Black-Right-Pointing-Pointer AIRE is acetylated by the acetyltransferases p300 and CBP. Black-Right-Pointing-Pointer Acetylation occurs between CARD and SAND domains and within the SAND domain. Black-Right-Pointing-Pointer Acetylation increases the size of AIRE nuclear dots. Black-Right-Pointing-Pointer Acetylation increases AIRE protein stability. Black-Right-Pointing-Pointer AIRE acetylation mimic regulates a different set of AIRE

  20. Reduced Wall Acetylation Proteins Play Vital and Distinct Roles in Cell Wall O-Acetylation in Arabidopsis1[C][W][OPEN

    PubMed Central

    Manabe, Yuzuki; Verhertbruggen, Yves; Gille, Sascha; Harholt, Jesper; Chong, Sun-Li; Pawar, Prashant Mohan-Anupama; Mellerowicz, Ewa J.; Tenkanen, Maija; Cheng, Kun; Pauly, Markus; Scheller, Henrik Vibe

    2013-01-01

    The Reduced Wall Acetylation (RWA) proteins are involved in cell wall acetylation in plants. Previously, we described a single mutant, rwa2, which has about 20% lower level of O-acetylation in leaf cell walls and no obvious growth or developmental phenotype. In this study, we generated double, triple, and quadruple loss-of-function mutants of all four members of the RWA family in Arabidopsis (Arabidopsis thaliana). In contrast to rwa2, the triple and quadruple rwa mutants display severe growth phenotypes revealing the importance of wall acetylation for plant growth and development. The quadruple rwa mutant can be completely complemented with the RWA2 protein expressed under 35S promoter, indicating the functional redundancy of the RWA proteins. Nevertheless, the degree of acetylation of xylan, (gluco)mannan, and xyloglucan as well as overall cell wall acetylation is affected differently in different combinations of triple mutants, suggesting their diversity in substrate preference. The overall degree of wall acetylation in the rwa quadruple mutant was reduced by 63% compared with the wild type, and histochemical analysis of the rwa quadruple mutant stem indicates defects in cell differentiation of cell types with secondary cell walls. PMID:24019426

  1. Lysine Acetylation of CREBH Regulates Fasting-Induced Hepatic Lipid Metabolism.

    PubMed

    Kim, Hyunbae; Mendez, Roberto; Chen, Xuequn; Fang, Deyu; Zhang, Kezhong

    2015-12-01

    Cyclic AMP-responsive element-binding protein 3-like 3, hepatocyte specific (CREBH), is a hepatic transcription factor that functions as a key regulator of energy homeostasis. Here, we defined a regulatory CREBH posttranslational modification process, namely, lysine-specific acetylation, and its functional involvement in fasting-induced hepatic lipid metabolism. Fasting induces CREBH acetylation in mouse livers in a time-dependent manner, and this event is critical for CREBH transcriptional activity in regulating hepatic lipid homeostasis. The histone acetyltransferase PCAF-mediated acetylation and the deacetylase sirtuin-1-mediated deacetylation coexist to maintain CREBH acetylation states under fasting conditions. Site-directed mutagenesis and functional analyses revealed that the lysine (K) residue at position 294 (K294) within the bZIP domain of the CREBH protein is the site where fasting-induced acetylation/deacetylation occurs. Introduction of the acetylation-deficient (K294R) or acetylation-mimicking (K294Q) mutation inhibited or enhanced CREBH transcriptional activity, respectively. Importantly, CREBH acetylation at lysine 294 was required for the interaction and synergy between CREBH and peroxisome proliferator-activated receptor α (PPARα) in activating their target genes upon fasting or glucagon stimulation. Introduction of the CREBH lysine 294 mutation in the liver leads to hepatic steatosis and hyperlipidemia in animals under prolonged fasting. In summary, our study reveals a molecular mechanism by which fasting or glucagon stimulation modulates lipid homeostasis through acetylation of CREBH.

  2. Sirtuin-dependent reversible lysine acetylation of glutamine synthetases reveals an autofeedback loop in nitrogen metabolism.

    PubMed

    You, Di; Yin, Bin-Cheng; Li, Zhi-Hai; Zhou, Ying; Yu, Wen-Bang; Zuo, Peng; Ye, Bang-Ce

    2016-06-14

    In cells of all domains of life, reversible lysine acetylation modulates the function of proteins involved in central cellular processes such as metabolism. In this study, we demonstrate that the nitrogen regulator GlnR of the actinomycete Saccharopolyspora erythraea directly regulates transcription of the acuA gene (SACE_5148), which encodes a Gcn5-type lysine acetyltransferase. We found that AcuA acetylates two glutamine synthetases (GlnA1 and GlnA4) and that this lysine acetylation inactivated GlnA4 (GSII) but had no significant effect on GlnA1 (GSI-β) activity under the conditions tested. Instead, acetylation of GlnA1 led to a gain-of-function that modulated its interaction with the GlnR regulator and enhanced GlnR-DNA binding. It was observed that this regulatory function of acetylated GSI-β enzymes is highly conserved across actinomycetes. In turn, GlnR controls the catalytic and regulatory activities (intracellular acetylation levels) of glutamine synthetases at the transcriptional and posttranslational levels, indicating an autofeedback loop that regulates nitrogen metabolism in response to environmental change. Thus, this GlnR-mediated acetylation pathway provides a signaling cascade that acts from nutrient sensing to acetylation of proteins to feedback regulation. This work presents significant new insights at the molecular level into the mechanisms underlying the regulation of protein acetylation and nitrogen metabolism in actinomycetes. PMID:27247389

  3. Aspirin-mediated acetylation induces structural alteration and aggregation of bovine pancreatic insulin.

    PubMed

    Yousefi, Reza; Taheri, Behnaz; Alavi, Parnian; Shahsavani, Mohammad Bagher; Asadi, Zahra; Ghahramani, Maryam; Niazi, Ali; Alavianmehr, Mohammad Mehdi; Moosavi-Movahedi, Ali Akbar

    2016-01-01

    The simple aggregation of insulin under various chemical and physical stresses is still an important challenge for both pharmaceutical production and clinical formulation. In the storage form, this protein is subjected to various chemical modifications which alter its physicochemical and aggregation properties. Aspirin (acetylsalicylic acid) which is the most widely used medicine worldwide has been indicated to acetylate a large number of proteins both in vitro and in vivo. In this study, as insulin treated with aspirin at 37°C, a significant level of acetylation was observed by flourescamine and o-phthalaldehyde assay. Also, different spectroscopic techniques, gel electrophoresis, and microscopic assessment were applied to compare the structural variation and aggregation/fibrillation propensity among acetylated and non-acetylated insulin samples. The results of spectroscopic assessments elucidate that acetylation induces insulin unfolding which is accompanied with the exposure of protein hydrophobic patches, a transition from alpha-helix to beta-sheet and increased propensity of the protein for aggregation. The kinetic studies propose that acetylation increases aggregation rate of insulin under both thermal and chemical stresses. Also, gel electrophoresis and dynamic light scattering experiments suggest that acetylation induces insulin oligomerization. Additionally, the results of Thioflavin T fluorescence study, Congo red absorption assessment, and microscopic analysis suggest that acetylation with aspirin enhances the process of insulin fibrillation. Overall, the increased susceptibility of acetylated insulin for aggregation may reflect the fact that this type of modification has significant structural destabilizing effect which finally makes the protein more vulnerable for pathogenic aggregation/fibrillation.

  4. Lysine Acetylation of CREBH Regulates Fasting-Induced Hepatic Lipid Metabolism

    PubMed Central

    Kim, Hyunbae; Mendez, Roberto; Chen, Xuequn; Fang, Deyu

    2015-01-01

    Cyclic AMP-responsive element-binding protein 3-like 3, hepatocyte specific (CREBH), is a hepatic transcription factor that functions as a key regulator of energy homeostasis. Here, we defined a regulatory CREBH posttranslational modification process, namely, lysine-specific acetylation, and its functional involvement in fasting-induced hepatic lipid metabolism. Fasting induces CREBH acetylation in mouse livers in a time-dependent manner, and this event is critical for CREBH transcriptional activity in regulating hepatic lipid homeostasis. The histone acetyltransferase PCAF-mediated acetylation and the deacetylase sirtuin-1-mediated deacetylation coexist to maintain CREBH acetylation states under fasting conditions. Site-directed mutagenesis and functional analyses revealed that the lysine (K) residue at position 294 (K294) within the bZIP domain of the CREBH protein is the site where fasting-induced acetylation/deacetylation occurs. Introduction of the acetylation-deficient (K294R) or acetylation-mimicking (K294Q) mutation inhibited or enhanced CREBH transcriptional activity, respectively. Importantly, CREBH acetylation at lysine 294 was required for the interaction and synergy between CREBH and peroxisome proliferator-activated receptor α (PPARα) in activating their target genes upon fasting or glucagon stimulation. Introduction of the CREBH lysine 294 mutation in the liver leads to hepatic steatosis and hyperlipidemia in animals under prolonged fasting. In summary, our study reveals a molecular mechanism by which fasting or glucagon stimulation modulates lipid homeostasis through acetylation of CREBH. PMID:26438600

  5. Proteome-wide analysis of lysine acetylation in the plant pathogen Botrytis cinerea

    PubMed Central

    Lv, Binna; Yang, Qianqian; Li, Delong; Liang, Wenxing; Song, Limin

    2016-01-01

    Lysine acetylation is a dynamic and reversible post-translational modification that plays an important role in diverse cellular processes. Botrytis cinerea is the most thoroughly studied necrotrophic species due to its broad host range and huge economic impact. However, to date, little is known about the functions of lysine acetylation in this plant pathogen. In this study, we determined the lysine acetylome of B. cinerea through the combination of affinity enrichment and high-resolution LC-MS/MS analysis. Overall, 1582 lysine acetylation sites in 954 proteins were identified. Bioinformatics analysis shows that the acetylated proteins are involved in diverse biological functions and show multiple cellular localizations. Several particular amino acids preferred near acetylation sites, including KacY, KacH, Kac***R, KacF, FKac and Kac***K, were identified in this organism. Protein interaction network analysis demonstrates that a variety of interactions are modulated by protein acetylation. Interestingly, 6 proteins involved in virulence of B. cinerea, including 3 key components of the high-osmolarity glycerol pathway, were found to be acetylated, suggesting that lysine acetylation plays regulatory roles in pathogenesis. These data provides the first comprehensive view of the acetylome of B. cinerea and serves as a rich resource for functional analysis of lysine acetylation in this plant pathogen. PMID:27381557

  6. Ionizing radiation induces immediate protein acetylation changes in human cardiac microvascular endothelial cells

    PubMed Central

    Barjaktarovic, Zarko; Kempf, Stefan J.; Sriharshan, Arundhathi; Merl-Pham, Juliane; Atkinson, Michael J.; Tapio, Soile

    2015-01-01

    Reversible lysine acetylation is a highly regulated post-translational protein modification that is known to regulate several signaling pathways. However, little is known about the radiation-induced changes in the acetylome. In this study, we analyzed the acute post-translational acetylation changes in primary human cardiac microvascular endothelial cells 4 h after a gamma radiation dose of 2 Gy. The acetylated peptides were enriched using anti-acetyl conjugated agarose beads. A total of 54 proteins were found to be altered in their acetylation status, 23 of which were deacetylated and 31 acetylated. Pathway analyses showed three protein categories particularly affected by radiation-induced changes in the acetylation status: the proteins involved in the translation process, the proteins of stress response, and mitochondrial proteins. The activation of the canonical and non-canonical Wnt signaling pathways affecting actin cytoskeleton signaling and cell cycle progression was predicted. The protein expression levels of two nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases, sirtuin 1 and sirtuin 3, were significantly but transiently upregulated 4 but not 24 h after irradiation. The status of the p53 protein, a target of sirtuin 1, was found to be rapidly stabilized by acetylation after radiation exposure. These findings indicate that post-translational modification of proteins by acetylation and deacetylation is essentially affecting the radiation response of the endothelium. PMID:25840449

  7. First Comprehensive Proteome Analyses of Lysine Acetylation and Succinylation in Seedling Leaves of Brachypodium distachyon L.

    PubMed Central

    Zhen, Shoumin; Deng, Xiong; Wang, Jian; Zhu, Gengrui; Cao, Hui; Yuan, Linlin; Yan, Yueming

    2016-01-01

    Protein acetylation and succinylation are the most crucial protein post-translational modifications (PTMs) involved in the regulation of plant growth and development. In this study, we present the first lysine-acetylation and lysine-succinylation proteome analysis of seedling leaves in Brachypodium distachyon L (Bd). Using high accuracy nano LC-MS/MS combined with affinity purification, we identified a total of 636 lysine-acetylated sites in 353 proteins and 605 lysine-succinylated sites in 262 proteins. These proteins participated in many biology processes, with various molecular functions. In particular, 119 proteins and 115 sites were found to be both acetylated and succinylated, simultaneously. Among the 353 acetylated proteins, 148 had acetylation orthologs in Oryza sativa L., Arabidopsis thaliana, Synechocystis sp. PCC 6803, and Glycine max L. Among the 262 succinylated proteins, 170 of them were found to have homologous proteins in Oryza sativa L., Escherichia coli, Sacchayromyces cerevisiae, or Homo sapiens. Motif-X analysis of the acetylated and succinylated sites identified two new acetylated motifs (K---K and K-I-K) and twelve significantly enriched succinylated motifs for the first time, which could serve as possible binding loci for future studies in plants. Our comprehensive dataset provides a promising starting point for further functional analysis of acetylation and succinylation in Bd and other plant species. PMID:27515067

  8. Metabolism of 1-acyl-2-acetyl-sn-glycero-3-phosphocholine in the human neutrophil

    SciTech Connect

    Triggiani, M.; D'Souza, D.M.; Chilton, F.H. )

    1991-04-15

    The biosynthesis of 1-acyl-2-acetyl-sn-glycero-3-phosphocholine (1-acyl-2-acetyl-GPC) together with that of 1-alkyl-2-acetyl-GPC (platelet-activating factor) has been demonstrated in a variety of inflammatory cells and tissues. It has been hypothesized that the relative proportion of these phospholipids produced upon cell activation may be influenced by their rates of catabolism. We studied the catabolism of 1-acyl-2-acetyl-GPC in resting and activated human neutrophils and compared it to that of 1-alkyl-2-acetyl-GPC. Neutrophils rapidly catabolize both 1-alkyl-2-acetyl-GPC and 1-acyl-2-acetyl-GPC; however, the rate of catabolism of 1-acyl-2-acetyl-GPC is approximately 2-fold higher than that of 1-alkyl-2-acetyl-GPC. In addition, most of 1-acyl-2-acetyl-GPC is catabolized through a pathway different from that of 1-alkyl-2-acetyl-GPC. The main step in the catabolism of 1-acyl-2-acetyl-GPC is the removal of the long chain at the sn-1 position; the long chain residue is subsequently incorporated either into triglycerides or into phosphatidylcholine. The 1-lyso-2-acetyl-GPC formed in this reaction is then further degraded to glycerophosphocholine, choline, or phosphocholine. 1-Acyl-2-acetyl-GPC is also catabolized, to a lesser extent, through deacetylation at the sn-2 position and reacylation with a long chain fatty acid. Stimulation of neutrophils by A23187 results in a higher rate of catabolism of 1-acyl-2-acetyl-GPC by increasing both the removal of the long chain at the sn-1 position and the deacetylation-reacylation at the sn-2 position. In a broken cell preparation, the cytosolic fraction of the neutrophil was shown to contain an enzyme activity which cleaved the sn-1 position of 1-acyl-2-acetyl-GPC and 1-acyl-2-lyso-GPC but not of 1,2-diacyl-GPC.

  9. [Alcohol and crime].

    PubMed

    Lévay, Boglárka

    2006-01-01

    The role alcohol abuse plays in criminality has been a matter of primary concern for scholars for decades, as indicated by numerous studies and research projects. Most of these studies focus on determining the presence of a relationship between criminal behaviour and alcohol use, and whether criminal inclinations increase with the consumption of alcohol. Research shows that alcohol use indeed increases the risk of criminal behaviour, and that there is an especially strong and consistent correlation between alcohol abuse and violent crimes. However, researchers still disagree on the exact extent to which alcohol use effects criminality, and on the mechanisms causing alcohol to induce violent behaviour. A significant proportion of studies have focused in recent years on aggressive behaviour as a result of drinking alcohol. One of the most important means of measurement is the study of violent behaviour in places where alcohol is on sale. Studying the forms and frequency of violence in pubs and near off-licence stores greatly enables experts to understand the general context of the problem. This is the reason for the increasing interest in the topic throughout the past few decades. The present study focuses mainly on the literature published in English and German in leading journals of criminology since 1980, as well as on the most recent and fundamental publications on the topic, with special regard to results concerning drinking habits, and the relationship between drinking alcohol and violent or criminal behaviour, respectively.

  10. Identification and suppression of the p-coumaroyl-CoA: hydroxycinnamyl alcohol transferase in Zea mays L.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grasses are unique in the relatively high levels of p-coumarates (pCA) within their cell walls, though the role of pCA within the wall matrix remains unclear. Corn (Zea mays L.) contains large amounts of pCA, especially in stem tissues (15% of total isolated lignin). Incorporation of pCA into cell w...

  11. Purification and Biochemical Characterization of Glutathione S-Transferase from Down Syndrome and Normal Children Erythrocytes: A Comparative Study

    ERIC Educational Resources Information Center

    Hamed, Ragaa R.; Maharem, Tahany M.; Abdel-Meguid, Nagwa; Sabry, Gilane M.; Abdalla, Abdel-Monem; Guneidy, Rasha A.

    2011-01-01

    Down syndrome (DS) is the phenotypic manifestation of trisomy 21. Our study was concerned with the characterization and purification of glutathione S-transferase enzyme (GST) from normal and Down syndrome (DS) erythrocytes to illustrate the difference in the role of this enzyme in the cell. Glutathione S-transferase and glutathione (GSH) was…

  12. Alcohol Expectancies in Young Adult Sons of Alcoholics and Controls.

    ERIC Educational Resources Information Center

    Brown, Sandra A.; And Others

    Adolescent offspring of alcoholics have been found to have higher alcohol reinforcement expectancies than do teenagers from nonalcoholic families. In particular, those with a positive family history of alcoholism expect more cognitive and motor enhancement with alcohol consumption. This study examined the alcohol expectancies of 58 matched pairs…

  13. Exposure to Televised Alcohol Ads and Subsequent Adolescent Alcohol Use

    ERIC Educational Resources Information Center

    Stacy, Alan W.; Zogg, Jennifer B.; Unger, Jennifer B.; Dent, Clyde W.

    2004-01-01

    Objective : To assess the impact of televised alcohol commercials on adolescents' alcohol use. Methods : Adolescents completed questionnaires about alcohol commercials and alcohol use in a prospective study. Results : A one standard deviation increase in viewing television programs containing alcohol commercials in seventh grade was associated…

  14. The Metabolic Fate of Deoxynivalenol and Its Acetylated Derivatives in a Wheat Suspension Culture: Identification and Detection of DON-15-O-Glucoside, 15-Acetyl-DON-3-O-Glucoside and 15-Acetyl-DON-3-Sulfate

    PubMed Central

    Schmeitzl, Clemens; Warth, Benedikt; Fruhmann, Philipp; Michlmayr, Herbert; Malachová, Alexandra; Berthiller, Franz; Schuhmacher, Rainer; Krska, Rudolf; Adam, Gerhard

    2015-01-01

    Deoxynivalenol (DON) is a protein synthesis inhibitor produced by the Fusarium species, which frequently contaminates grains used for human or animal consumption. We treated a wheat suspension culture with DON or one of its acetylated derivatives, 3-acetyl-DON (3-ADON), 15-acetyl-DON (15-ADON) and 3,15-diacetyl-DON (3,15-diADON), and monitored the metabolization over a course of 96 h. Supernatant and cell extract samples were analyzed using a tailored LC-MS/MS method for the quantification of DON metabolites. We report the formation of tentatively identified DON-15-O-β-D-glucoside (D15G) and of 15-acetyl-DON-3-sulfate (15-ADON3S) as novel deoxynivalenol metabolites in wheat. Furthermore, we found that the recently identified 15-acetyl-DON-3-O-β-D-glucoside (15-ADON3G) is the major metabolite produced after 15-ADON challenge. 3-ADON treatment led to a higher intracellular content of toxic metabolites after six hours compared to all other treatments. 3-ADON was exclusively metabolized into DON before phase II reactions occurred. In contrast, we found that 15-ADON was directly converted into 15-ADON3G and 15-ADON3S in addition to metabolization into deoxynivalenol-3-O-β-D-glucoside (D3G). This study highlights significant differences in the metabolization of DON and its acetylated derivatives. PMID:26274975

  15. The Metabolic Fate of Deoxynivalenol and Its Acetylated Derivatives in a Wheat Suspension Culture: Identification and Detection of DON-15-O-Glucoside, 15-Acetyl-DON-3-O-Glucoside and 15-Acetyl-DON-3-Sulfate.

    PubMed

    Schmeitzl, Clemens; Warth, Benedikt; Fruhmann, Philipp; Michlmayr, Herbert; Malachová, Alexandra; Berthiller, Franz; Schuhmacher, Rainer; Krska, Rudolf; Adam, Gerhard

    2015-08-12

    Deoxynivalenol (DON) is a protein synthesis inhibitor produced by the Fusarium species, which frequently contaminates grains used for human or animal consumption. We treated a wheat suspension culture with DON or one of its acetylated derivatives, 3-acetyl-DON (3-ADON), 15-acetyl-DON (15-ADON) and 3,15-diacetyl-DON (3,15-diADON), and monitored the metabolization over a course of 96 h. Supernatant and cell extract samples were analyzed using a tailored LC-MS/MS method for the quantification of DON metabolites. We report the formation of tentatively identified DON-15-O-β-D-glucoside (D15G) and of 15-acetyl-DON-3-sulfate (15-ADON3S) as novel deoxynivalenol metabolites in wheat. Furthermore, we found that the recently identified 15-acetyl-DON-3-O-β-D-glucoside (15-ADON3G) is the major metabolite produced after 15-ADON challenge. 3-ADON treatment led to a higher intracellular content of toxic metabolites after six hours compared to all other treatments. 3-ADON was exclusively metabolized into DON before phase II reactions occurred. In contrast, we found that 15-ADON was directly converted into 15-ADON3G and 15-ADON3S in addition to metabolization into deoxynivalenol-3-O-β-D-glucoside (D3G). This study highlights significant differences in the metabolization of DON and its acetylated derivatives.

  16. Tianeptine and alcohol dependence.

    PubMed

    Favre, J D; Guelfi-Sozzi, C; Delalleau, B; Lôo, H

    1997-10-01

    Several arguments are in favour of the use of antidepressant drugs in alcohol-dependent patients, especially those acting on the serotoninergic system: (1) neurochemical data indicate the interaction between alcohol and 5-HT metabolism, (2) pharmacological studies show an improvement in the behaviour of alcoholized animals treated with antidepressants, (3) depression is a frequent disease in alcoholic patients. Tianeptine has been shown to be active in the treatment of depression in patients with history of alcohol abuse or dependence. In a first double-blind study performed versus amitryptiline, depression after withdrawal was improved by tianeptine, and biological abnormalities usually related to chronic alcohol intake tended to decrease. Similar results were found in an open study carried out on 277 alcoholic patients treated for 1 year. As these patients were depressed, no definite conclusion could be drawn from these results in respect of a specific action of tianeptine on alcohol dependence. Thus, a multicentre double-blind study has been performed which compared tianeptine (12.5 mg t.i.d) and placebo in 342 non-depressed patients fulfilling DSM-III-R criteria for Psychoactive Substance Dependence (alcohol). Other inclusion criteria were: daily alcohol intake higher than 80 g, minimum score of 3 on the Short-Mast Questionnaire, mean corpuscular volume above 98 fl and/or gamma Gt more than twice the upper limit of normal. The patients were treated for 9 months. The intention-to-treat population and the per protocol population were made up of 327 patients and 111 patients, respectively. The main efficacy criterion was the absence of alcoholic relapse (abstinence) defined by the patient's statements, the investigators clinical judgement and some biological parameters: alcohol blood levels, gamma Gt levels. Secondary criteria were the evolution of the alcohol consumption in the patients who relapsed, cumulative abstinence duration, a visual analogue scale for the

  17. The dynamic organization of fungal acetyl-CoA carboxylase

    PubMed Central

    Hunkeler, Moritz; Stuttfeld, Edward; Hagmann, Anna; Imseng, Stefan; Maier, Timm

    2016-01-01

    Acetyl-CoA carboxylases (ACCs) catalyse the committed step in fatty-acid biosynthesis: the ATP-dependent carboxylation of acetyl-CoA to malonyl-CoA. They are important regulatory hubs for metabolic control and relevant drug targets for the treatment of the metabolic syndrome and cancer. Eukaryotic ACCs are single-chain multienzymes characterized by a large, non-catalytic central domain (CD), whose role in ACC regulation remains poorly characterized. Here we report the crystal structure of the yeast ACC CD, revealing a unique four-domain organization. A regulatory loop, which is phosphorylated at the key functional phosphorylation site of fungal ACC, wedges into a crevice between two domains of CD. Combining the yeast CD structure with intermediate and low-resolution data of larger fragments up to intact ACCs provides a comprehensive characterization of the dynamic fungal ACC architecture. In contrast to related carboxylases, large-scale conformational changes are required for substrate turnover, and are mediated by the CD under phosphorylation control. PMID:27073141

  18. Protein acetylation sites mediated by Schistosoma mansoni GCN5

    SciTech Connect

    Moraes Maciel, Renata de; Furtado Madeiro da Costa, Rodrigo; Meirelles Bastosde Oliveira, Francisco; Rumjanek, Franklin David; Fantappie, Marcelo Rosado

    2008-05-23

    The transcriptional co-activator GCN5, a histone acetyltransferase (HAT), is part of large multimeric complexes that are required for chromatin remodeling and transcription activation. As in other eukaryotes, the DNA from the parasite Schistosome mansoni is organized into nucleosomes and the genome encodes components of chromatin-remodeling complexes. Using a series of synthetic peptides we determined that Lys-14 of histone H3 was acetylated by the recombinant SmGCN5-HAT domain. SmGCN5 was also able to acetylate schistosome non-histone proteins, such as the nuclear receptors SmRXR1 and SmNR1, and the co-activator SmNCoA-62. Electron microscopy revealed the presence of SmGCN5 protein in the nuclei of vitelline cells. Within the nucleus, SmGCN5 was found to be located in interchromatin granule clusters (IGCs), which are transcriptionally active structures. The data suggest that SmGCN5 is involved in transcription activation.

  19. The dynamic organization of fungal acetyl-CoA carboxylase

    NASA Astrophysics Data System (ADS)

    Hunkeler, Moritz; Stuttfeld, Edward; Hagmann, Anna; Imseng, Stefan; Maier, Timm

    2016-04-01

    Acetyl-CoA carboxylases (ACCs) catalyse the committed step in fatty-acid biosynthesis: the ATP-dependent carboxylation of acetyl-CoA to malonyl-CoA. They are important regulatory hubs for metabolic control and relevant drug targets for the treatment of the metabolic syndrome and cancer. Eukaryotic ACCs are single-chain multienzymes characterized by a large, non-catalytic central domain (CD), whose role in ACC regulation remains poorly characterized. Here we report the crystal structure of the yeast ACC CD, revealing a unique four-domain organization. A regulatory loop, which is phosphorylated at the key functional phosphorylation site of fungal ACC, wedges into a crevice between two domains of CD. Combining the yeast CD structure with intermediate and low-resolution data of larger fragments up to intact ACCs provides a comprehensive characterization of the dynamic fungal ACC architecture. In contrast to related carboxylases, large-scale conformational changes are required for substrate turnover, and are mediated by the CD under phosphorylation control.

  20. Autotrophic acetyl coenzyme A biosynthesis in Methanococcus maripaludis.

    PubMed Central

    Shieh, J; Whitman, W B

    1988-01-01

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

  1. Characterisation of two alcohol acyltransferases from kiwifruit (Actinidia spp.) reveals distinct substrate preferences.

    PubMed

    Günther, Catrin S; Chervin, Christian; Marsh, Ken B; Newcomb, Richard D; Souleyre, Edwige J F

    2011-06-01

    Volatile esters are key compounds of kiwifruit flavour and are formed by alcohol acyltransferases that belong to the BAHD acyltransferase superfamily. Quantitative RT-PCR was used to screen kiwifruit-derived expressed sequence tags with proposed acyltransferase function in order to select ripening-specific sequences and test their involvement in alcohol acylation. The screening criterion was for at least 10-fold increased transcript accumulation in ripe compared with unripe kiwifruit and in response to ethylene. Recombinant expression in yeast revealed alcohol acyltransferase activity for Actinidia-derived AT1, AT16 and the phylogenetically distinct AT9, using various alcohol and acyl-CoA substrates. Functional characterisation of AT16 and AT9 demonstrated striking differences in their substrate preferences and apparent catalytic efficiencies (V'(max)K(m)(-1)). Thus revealing benzoyl-CoA:alcohol O-acyltransferase activity for AT16 and acetyl-CoA:alcohol O-acyltransferase activity for AT9. Both kiwifruit-derived enzymes displayed higher reaction rates with butanol compared with ethanol, even though ethanol is the main alcohol in ripe fruit. Since ethyl acetate and ethyl benzoate are major esters in ripe kiwifruit, we suggest that fruit characteristic volatile profiles result from a combination of substrate availability and specificity of individual alcohol acyltransferases.

  2. [Alcohol and nutrition].

    PubMed

    Maillot, F; Farad, S; Lamisse, F

    2001-11-01

    Alcoholism and alcohol-associated organ injury is one of the major health problems worldwide. Alcohol may lead to an alteration in intermediary metabolism and the relation between alcohol intake and body weight is a paradox. The effect of alcohol intake on resting metabolic rate, assessed by indirect calorimetry, and lipid oxidation, is still controversial. Small quantities of ethanol seem to have no effect on body weight. Ingestion of moderate amounts may lead to an increase in body weight, via a lipid-oxidizing suppressive effect. Chronic intake of excessive amounts in alcoholics leads to a decrease in body weight, probably via increased lipid oxidation and energy expenditure. Chronic ethanol abuse alters lipid-soluble (vitamins A, D and E) and water-soluble (B-complex vitamins, vitamin C) vitamins status, and some trace elements status such as magnesium, selenium or zinc.

  3. Update on Alcoholic Hepatitis.

    PubMed

    Torok, Natalie J

    2015-11-02

    Alcoholic liver disease is one of the most prevalent liver diseases worldwide, and a major cause of morbidity and mortality. Alcoholic hepatitis is a severe form of liver injury in patients with alcohol abuse, can present as an acute on chronic liver failure associated with a rapid decline in liver synthetic function, and consequent increase in mortality. Despite therapy, about 30%-50% of patients with severe alcoholic hepatitis eventually die. The pathogenic pathways that lead to the development of alcoholic hepatitis are complex and involve oxidative stress, gut dysbiosis, and dysregulation of the innate and adaptive immune system with injury to the parenchymal cells and activation of hepatic stellate cells. As accepted treatment approaches are currently limited, a better understanding of the pathophysiology would be required to generate new approaches that improve outcomes. This review focuses on recent advances in the diagnosis, pathogenesis of alcoholic hepatitis and novel treatment strategies.

  4. Update on Alcoholic Hepatitis

    PubMed Central

    Torok, Natalie J.

    2015-01-01

    Alcoholic liver disease is one of the most prevalent liver diseases worldwide, and a major cause of morbidity and mortality. Alcoholic hepatitis is a severe form of liver injury in patients with alcohol abuse, can present as an acute on chronic liver failure associated with a rapid decline in liver synthetic function, and consequent increase in mortality. Despite therapy, about 30%–50% of patients with severe alcoholic hepatitis eventually die. The pathogenic pathways that lead to the development of alcoholic hepatitis are complex and involve oxidative stress, gut dysbiosis, and dysregulation of the innate and adaptive immune system with injury to the parenchymal cells and activation of hepatic stellate cells. As accepted treatment approaches are currently limited, a better understanding of the pathophysiology would be required to generate new approaches that improve outcomes. This review focuses on recent advances in the diagnosis, pathogenesis of alcoholic hepatitis and novel treatment strategies. PMID:26540078

  5. Alcoholic liver disease: Treatment

    PubMed Central

    Suk, Ki Tae; Kim, Moon Young; Baik, Soon Koo

    2014-01-01

    The excess consumption of alcohol is associated with alcoholic liver diseases (ALD). ALD is a major healthcare problem, personal and social burden, and significant reason for economic loss worldwide. The ALD spectrum includes alcoholic fatty liver, alcoholic hepatitis, cirrhosis, and the development of hepatocellular carcinoma. The diagnosis of ALD is based on a combination of clinical features, including a history of significant alcohol intake, evidence of liver disease, and laboratory findings. Abstinence is the most important treatment for ALD and the treatment plan varies according to the stage of the disease. Various treatments including abstinence, nutritional therapy, pharmacological therapy, psychotherapy, and surgery are currently available. For severe alcoholic hepatitis, corticosteroid or pentoxifylline are recommended based on the guidelines. In addition, new therapeutic targets are being under investigation. PMID:25278689

  6. Biobreeding rat islets exhibit reduced antioxidative defense and N-acetyl cysteine treatment delays type 1 diabetes

    PubMed Central

    Bogdani, Marika; Henschel, Angela M.; Kansra, Sanjay; Fuller, Jessica M.; Geoffrey, Rhonda; Jia, Shuang; Kaldunski, Mary L.; Pavletich, Scott; Prosser, Simon; Chen, Yi-Guang; Lernmark, Åke; Hessner, Martin J.

    2014-01-01

    Islet-level oxidative stress has been proposed as a trigger for type 1 diabetes (T1D), and release of cytokines by infiltrating immune cells further elevates reactive oxygen species (ROS), exacerbating β cell duress. To identify genes/mechanisms involved with diabeto-genesis at the β cell level, gene expression profiling and targeted follow-up studies were used to investigate islet activity in the biobreeding (BB) rat. Forty-day-old spontaneously diabetic lymphopenic BB DRlyp/lyp rats (before T cell insulitis) as well as nondiabetic BB DR+/+ rats, nondiabetic but lymphopenic F344lyp/lyp rats, and healthy Fischer (F344) rats were examined. Gene expression profiles of BB rat islets were highly distinct from F344 islets and under-expressed numerous genes involved in ROS metabolism, including glutathione S-transferase (GST) family members (Gstm2, Gstm4, Gstm7, Gstt1, Gstp1, and Gstk1), superoxide dismutases (Sod2 and Sod3), peroxidases, and peroxiredoxins. This pattern of under-expression was not observed in brain, liver, or muscle. Compared with F344 rats, BB rat pancreata exhibited lower GST protein levels, while plasma GST activity was found significantly lower in BB rats. Systemic administration of the antioxidant N-acetyl cysteine to DRlyp/lyp rats altered abundances of peripheral eosinophils, reduced severity of insulitis, and significantly delayed but did not prevent diabetes onset. We find evidence of β cell dysfunction in BB rats independent of T1D progression, which includes lower expression of genes related to antioxidative defense mechanisms during the pre-onset period that may contribute to overall T1D susceptibility. PMID:23111281

  7. Structure-Based Design of Inhibitors of the Crucial Cysteine Biosynthetic Pathway Enzyme O-Acetyl Serine Sulfhydrylase.

    PubMed

    Mazumder, Mohit; Gourinath, Samudrala

    2016-01-01

    The cysteine biosynthetic pathway is of fundamental importance for the growth, survival, and pathogenicity of the many pathogens. This pathway is present in many species but is absent in mammals. The ability of pathogens to counteract the oxidative defences of a host is critical for the survival of these pathogens during their long latent phases, especially in anaerobic pathogens such as Entamoeba histolytica, Leishmania donovani, Trichomonas vaginalis, and Salmonella typhimurium. All of these organisms rely on the de novo cysteine biosynthetic pathway to assimilate sulphur and maintain a ready supply of cysteine. The de novo cysteine biosynthetic pathway, on account of its being important for the survival of pathogens and at the same time being absent in mammals, is an important drug target for diseases such as amoebiasis, trichomoniasis & tuberculosis. Cysteine biosynthesis is catalysed by two enzymes: serine acetyl transferase (SAT) followed by O-acetylserine sulfhydrylase (OASS). OASS is well studied, and with the availability of crystal structures of this enzyme in different conformations, it is a suitable template for structure-based inhibitor development. Moreover, OASS is highly conserved, both structurally and sequence-wise, among the above-mentioned organisms. There have been several reports of inhibitor screening and development against this enzyme from different organisms such as Salmonella typhimurium, Mycobacterium tuberculosis and Entamoeba histolytica. All of these inhibitors have been reported to display micromolar to nanomolar binding affinities for the open conformation of the enzyme. In this review, we highlight the structural similarities of this enzyme in different organisms and the attempts for inhibitor development so far. We also propose that the intermediate state of the enzyme may be the ideal target for the design of effective highaffinity inhibitors.

  8. Sulfation of p-nitrophenyl-N-acetyl-beta-D-galactosaminide with a microsomal fraction from cultured chondrocytes

    SciTech Connect

    Habuchi, O.; Conrad, H.E.

    1985-10-25

    Chick embryo chondrocyte microsomes containing intact Golgi vesicles took up 3'-phosphoadenosine-5'-phospho(TVS)sulfate ((TVS)PAPS) in a time- and temperature-dependent, substrate-saturable manner. When (TVS)PAPS and p-nitrophenyl-N-acetyl-beta-D-galactosaminide (pNP-GalNAc) were added to the incubation in the absence of detergent, the microsomes catalyzed the transfer of sulfate from (TVS)PAPS to pNP-GalNAc to form pNP-GalNAc-6-TVSO4. The apparent Km values for PAPS in the uptake and the pNP-GalNAc sulfation reactions were 2 X 10(-7) and 2 X 10(-6) M, respectively. The sulfation of pNP-GalNAc by the microsomal preparation was inhibited by detergent. The microsomal fraction also catalyzed the transfer of sulfate from (TVS)PAPS to oligosaccharides prepared from chondroitin. However, in contrast to the sulfation of pNP-GalNAc, the rate of sulfation of these oligosaccharides was low in the absence of detergent and was markedly stimulated when detergent was added. Sulfation of pNP-GalNAc by the freeze-thawed microsomes was inhibited when the octasaccharide prepared from chondroitin was present in the reaction mixture. As the PAPS that had been internalized in the microsomal vesicles was consumed in the sulfation of pNP-GalNAc, more (TVS)PAPS was taken up and the sulfated pNP-GalNAc was released from the vesicles. These observations suggest that pNP-GalNAc may serve as a model membrane-permeable substrate for study of the 6-sulfo-transferase reaction involved in sulfation of chondroitin sulfate in intact Golgi vesicles.

  9. Effect of Acetyl-L-Carnitine on Antioxidant Status, Lipid Peroxidation, and Oxidative Damage of Arsenic in Rat.

    PubMed

    Sepand, Mohammad Reza; Razavi-Azarkhiavi, Kamal; Omidi, Ameneh; Zirak, Mohammad Reza; Sabzevari, Samin; Kazemi, Ali Reza; Sabzevari, Omid

    2016-05-01

    Arsenic (As) is a widespread environmental contaminant present around the world in both organic and inorganic forms. Oxidative stress is postulated as the main mechanism for As-induced toxicity. This study was planned to examine the protective effect of acetyl-L-carnitine (ALC) on As-induced oxidative damage in male rats. Animals were randomly divided into four groups of control (saline), sodium arsenite (NaAsO2, 20 mg/kg), ALC (300 mg/kg), and NaAsO2 plus ALC. Animals were dosed orally for 28 successive days. Blood and tissue samples including kidney, brain, liver, heart, and lung were collected on the 28th day and evaluated for oxidative damage and histological changes. NaAsO2 exposure caused a significant lipid peroxidation as evidenced by elevation in thiobarbituric acid-reactive substances (TBARS). The activity of antioxidant enzymes such as glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD), as well as sulfhydryl group content (SH group) was significantly suppressed in various organs following NaAsO2 treatment (P < 0.05). Furthermore, NaAsO2 administration increased serum values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and bilirubin. Our findings revealed that co-administration of ALC and NaAsO2 significantly suppressed the oxidative damage induced by NaAsO2. Tissue histological studies have confirmed the biochemical findings and provided evidence for the beneficial role of ALC. The results concluded that ALC attenuated NaAsO2-induced toxicity, and this protective effect may result from the ability of ALC in maintaining oxidant-antioxidant balance. PMID:26349760

  10. Effect of Acetyl-L-Carnitine on Antioxidant Status, Lipid Peroxidation, and Oxidative Damage of Arsenic in Rat.

    PubMed

    Sepand, Mohammad Reza; Razavi-Azarkhiavi, Kamal; Omidi, Ameneh; Zirak, Mohammad Reza; Sabzevari, Samin; Kazemi, Ali Reza; Sabzevari, Omid

    2016-05-01

    Arsenic (As) is a widespread environmental contaminant present around the world in both organic and inorganic forms. Oxidative stress is postulated as the main mechanism for As-induced toxicity. This study was planned to examine the protective effect of acetyl-L-carnitine (ALC) on As-induced oxidative damage in male rats. Animals were randomly divided into four groups of control (saline), sodium arsenite (NaAsO2, 20 mg/kg), ALC (300 mg/kg), and NaAsO2 plus ALC. Animals were dosed orally for 28 successive days. Blood and tissue samples including kidney, brain, liver, heart, and lung were collected on the 28th day and evaluated for oxidative damage and histological changes. NaAsO2 exposure caused a significant lipid peroxidation as evidenced by elevation in thiobarbituric acid-reactive substances (TBARS). The activity of antioxidant enzymes such as glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD), as well as sulfhydryl group content (SH group) was significantly suppressed in various organs following NaAsO2 treatment (P < 0.05). Furthermore, NaAsO2 administration increased serum values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and bilirubin. Our findings revealed that co-administration of ALC and NaAsO2 significantly suppressed the oxidative damage induced by NaAsO2. Tissue histological studies have confirmed the biochemical findings and provided evidence for the beneficial role of ALC. The results concluded that ALC attenuated NaAsO2-induced toxicity, and this protective effect may result from the ability of ALC in maintaining oxidant-antioxidant balance.

  11. [Biological markers of alcoholism].

    PubMed

    Marcos Martín, M; Pastor Encinas, I; Laso Guzmán, F J

    2005-09-01

    Diagnosis of alcoholism is very important, given its high prevalence and possibility of influencing the disease course. For this reason, the so-called biological markers of alcoholism are useful. These are analytic parameters that alter in the presence of excessive alcohol consumption. The two most relevant markers are the gamma-glutamyltranspeptidase and carbohydrate deficient transferrin. With this clinical comment, we aim to contribute to the knowledge of these tests and promote its use in the clinical practice. PMID:16194480

  12. Preliminary X-ray crystallographic analysis of glutathione transferase zeta 1 (GSTZ1a-1a)

    SciTech Connect

    Boone, Christopher D.; Zhong, Guo; Smeltz, Marci; James, Margaret O. McKenna, Robert

    2014-01-21

    Crystals of glutathione transferase zeta 1 were grown and shown to diffract X-rays to 3.1 Å resolution. They belonged to space group P1, with unit-cell parameters a = 42.0, b = 49.6, c = 54.6 Å, α = 82.9, β = 69.9, γ = 73.4°.

  13. A tyrosine-reactive irreversible inhibitor for glutathione S-transferase Pi (GSTP1).

    PubMed

    Crawford, L A; Weerapana, E

    2016-05-24

    Glutathione S-transferase Pi (GSTP1) mediates cellular defense against reactive electrophiles. Here, we report LAS17, a dichlorotriazine-containing compound that irreversibly inhibits GSTP1 and is selective for GSTP1 within cellular proteomes. Mass spectrometry and mutational studies identified Y108 as the site of modification, providing a unique mode of GSTP1 inhibition. PMID:27113843

  14. Maize white seedling 3 results from disruption of homogentisate solanesyl transferase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize white seedling 3 (w3) has served as a model albino-seedling mutant since its discovery in 1923. We show here that the w3 phenotype is caused by disruptions in homogentisate solanesyl transferase (HST), an enzyme that catalyzes the committed step in plastoquinone-9 (PQ9) biosynthesis. This re...

  15. 21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... genetically modified cotton, oilseed rape, and tomatoes in accordance with the following prescribed conditions... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Aminoglycoside 3â²-phospho- transferase II. 573.130 Section 573.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  16. 21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... genetically modified cotton, oilseed rape, and tomatoes in accordance with the following prescribed conditions... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Aminoglycoside 3â²-phospho- transferase II. 573.130 Section 573.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  17. 21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... genetically modified cotton, oilseed rape, and tomatoes in accordance with the following prescribed conditions... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Aminoglycoside 3â²-phospho- transferase II. 573.130 Section 573.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  18. 21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... genetically modified cotton, oilseed rape, and tomatoes in accordance with the following prescribed conditions... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Aminoglycoside 3â²-phospho- transferase II. 573.130 Section 573.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  19. 21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... genetically modified cotton, oilseed rape, and tomatoes in accordance with the following prescribed conditions... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Aminoglycoside 3â²-phospho- transferase II. 573.130 Section 573.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  20. Development of isoform-specific sensors of polypeptide GalNAc-transferase activity.

    PubMed

    Song, Lina; Bachert, Collin; Schjoldager, Katrine T; Clausen, Henrik; Linstedt, Adam D

    2014-10-31

    Humans express up to 20 isoforms of GalNAc-transferase (herein T1-T20) that localize to the Golgi apparatus and initiate O-glycosylation. Regulation of this enzyme family affects a vast array of proteins transiting the secretory pathway and diseases arise upon misregulation of specific isoforms. Surprisingly, molecular probes to monitor GalNAc-transferase activity are lacking and there exist no effective global or isoform-specific inhibitors. Here we describe the development of T2- and T3-isoform specific fluorescence sensors that traffic in the secretory pathway. Each sensor yielded little signal when glycosylated but was strongly activated in the absence of its glycosylation. Specificity of each sensor was assessed in HEK cells with either the T2 or T3 enzymes deleted. Although the sensors are based on specific substrates of the T2 and T3 enzymes, elements in or near the enzyme recognition sequence influenced their activity and required modification, which we carried out based on previous in vitro work. Significantly, the modified T2 and T3 sensors were activated only in cells lacking their corresponding isozymes. Thus, we have developed T2- and T3-specific sensors that will be valuable in both the study of GalNAc-transferase regulation and in high-throughput screening for potential therapeutic regulators of specific GalNAc-transferases.

  1. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Galactose-1-phosphate uridyl transferase test system. 862.1315 Section 862.1315 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... hereditary disease galactosemia (disorder of galactose metabolism) in infants. (b) Classification. Class II....

  2. DNA BINDING POTENTIAL OF BROMODICHLOROMETHANE MEDIATED BY GLUTATHIONE S-TRANSFERASE THETA 1-1

    EPA Science Inventory


    DNA BINDING POTENTIAL OF BROMODICHLOROMETHANE MEDIATED BY GLUTATHIONE S-TRANSFERASE THETA 1-1. R A Pegram1 and M K Ross2. 2Curriculum in Toxicology, University of North Carolina, Chapel Hill, NC; 1Pharmacokinetics Branch, NHEERL, ORD, United States Environmental Protection Ag...

  3. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Galactose-1-phosphate uridyl transferase test system. 862.1315 Section 862.1315 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315...

  4. A practical fluorogenic substrate for high-throughput screening of glutathione S-transferase inhibitors.

    PubMed

    Fujikawa, Yuuta; Morisaki, Fumika; Ogura, Asami; Morohashi, Kana; Enya, Sora; Niwa, Ryusuke; Goto, Shinji; Kojima, Hirotatsu; Okabe, Takayoshi; Nagano, Tetsuo; Inoue, Hideshi

    2015-07-21

    We report a new fluorogenic substrate for glutathione S-transferase (GST), 3,4-DNADCF, enabling the assay with a low level of nonenzymatic background reaction. Inhibitors against Noppera-bo/GSTe14 from Drosophila melanogaster were identified by high throughput screening using 3,4-DNADCF, demonstrating the utility of this substrate.

  5. A tyrosine-reactive irreversible inhibitor for glutathione S-transferase Pi (GSTP1).

    PubMed

    Crawford, L A; Weerapana, E

    2016-05-24

    Glutathione S-transferase Pi (GSTP1) mediates cellular defense against reactive electrophiles. Here, we report LAS17, a dichlorotriazine-containing compound that irreversibly inhibits GSTP1 and is selective for GSTP1 within cellular proteomes. Mass spectrometry and mutational studies identified Y108 as the site of modification, providing a unique mode of GSTP1 inhibition.

  6. GLUTATHIONE S-TRANSFERASE THETA 1-1-DEPENDENT METABOLISM OF THE DISINFECTION BYPRODUCT BROMODICHLOROMETHANE

    EPA Science Inventory

    ABSTRACT
    Bromodichloromethane (BDCM), a prevalent drinking water disinfection by-product, was previously shown to be mutagenic in Salmonella expressing glutathione S-transferase (GST) theta 1-1 (GST T1-1). In the present study, in vitro experiments were performed to study the...

  7. 21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  8. 21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  9. 21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  10. 21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  11. 21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  12. 21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  13. 21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  14. 21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  15. 21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  16. 21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  17. Alcohol abuse and cigarette smoking are associated with global DNA hypermethylation: results from the German Investigation on Neurobiology in Alcoholism (GINA).

    PubMed

    Semmler, Alexander; Heese, Peter; Stoffel-Wagner, Birgit; Muschler, Marc; Heberlein, Annemarie; Bigler, Laurent; Prost, Jean-Christophe; Frieling, Helge; Kornhuber, Johannes; Banger, Markus; Bleich, Stefan; Hillemacher, Thomas; Linnebank, Michael

    2015-03-01

    Recent studies have shown that smoking and alcoholism may be associated with altered DNA methylation and that alcohol consumption might induce changes in DNA methylation by altering homocysteine metabolism. In this monocenter study, we included 363 consecutive patients referred for hospitalization for alcohol detoxification treatment. Blood samples were obtained on treatment days 1, 3, and 7 for measurement of global DNA methylation in leukocytes by liquid chromatography tandem mass spectrometry. Genomic DNA was used for genotyping the following seven genetic variants of homocysteine metabolism: cystathionine beta-synthase (CBS) c.844_855ins68, dihydrofolate-reductase (DHFR) c.594 + 59del19bp, methylenetetrahydrofolate-reductase (MTHFR) c.677C > T and c.1298A > C, methyltetrahydrofolate-transferase (MTR) c.2756A > G, reduced folate carrier 1 (RFC1) c.80G > A, and transcobalamin 2 c.776C > G. Multivariate linear regression showed a positive correlation of global DNA methylation with alcohol consumption and smoking on day 1 of hospitalization. DNA methylation was not correlated with homocysteine or vitamin plasma levels, nor with the tested genetic variants of homocysteine metabolism. This suggests a direct effect of alcohol consumption and smoking on DNA methylation, which is not mediated by effects of alcohol on homocysteine metabolism.

  18. Tobacco, Alcohol, Drugs, and Pregnancy

    MedlinePlus

    ... What are fetal alcohol spectrum disorders? • What is fetal alcohol syndrome? • What amounts of alcohol can cause FAS? • Is ... disabilities that can last a lifetime. What is fetal alcohol syndrome? Fetal alcohol syndrome (FAS) is the most severe ...

  19. Fetal Alcohol Syndrome "Chemical Genocide."

    ERIC Educational Resources Information Center

    Asetoyer, Charon

    In the Northern Plains of the United States, 100% of Indian reservations are affected by alcohol related problems. Approximately 90% of Native American adults are currently alcohol users or abusers or are recovering from alcohol abuse. Alcohol consumption has a devastating effect on the unborn. Fetal Alcohol Syndrome (FAS) is an irreversible birth…

  20. Changes in acetyl CoA levels during the early embryonic development of Xenopus laevis.

    PubMed

    Tsuchiya, Yugo; Pham, Uyen; Hu, Wanzhou; Ohnuma, Shin-Ichi; Gout, Ivan

    2014-01-01

    Coenzyme A (CoA) is a ubiquitous and fundamental intracellular cofactor. CoA acts as a carrier of metabolically important carboxylic acids in the form of CoA thioesters and is an obligatory component of a multitude of catabolic and anabolic reactions. Acetyl CoA is a CoA thioester derived from catabolism of all major carbon fuels. This metabolite is at a metabolic crossroads, either being further metabolised as an energy source or used as a building block for biosynthesis of lipids and cholesterol. In addition, acetyl CoA serves as the acetyl donor in protein acetylation reactions, linking metabolism to protein post-translational modifications. Recent studies in yeast and cultured mammalian cells have suggested that the intracellular level of acetyl CoA may play a role in the regulation of cell growth, proliferation and apoptosis, by affecting protein acetylation reactions. Yet, how the levels of this metabolite change in vivo during the development of a vertebrate is not known. We measured levels of acetyl CoA, free CoA and total short chain CoA esters during the early embryonic development of Xenopus laevis using HPLC. Acetyl CoA and total short chain CoA esters start to increase around midblastula transition (MBT) and continue to increase through stages of gastrulation, neurulation and early organogenesis. Pre-MBT embryos contain more free CoA relative to acetyl CoA but there is a shift in the ratio of acetyl CoA to CoA after MBT, suggesting a metabolic transition that results in net accumulation of acetyl CoA. At the whole-embryo level, there is an apparent correlation between the levels of acetyl CoA and levels of acetylation of a number of proteins including histones H3 and H2B. This suggests the level of acetyl CoA may be a factor, which determines the degree of acetylation of these proteins, hence may play a role in the regulation of embryogenesis. PMID:24831956

  1. Insights into K-Ras 4B regulation by post-translational lysine acetylation.

    PubMed

    Knyphausen, Philipp; Lang, Franziska; Baldus, Linda; Extra, Antje; Lammers, Michael

    2016-10-01

    Ras is a molecular switch cycling between an active, GTP-bound and an inactive, GDP-bound state. Mutations in Ras, mostly affecting the off-switch, are found in many human tumours. Recently, it has been shown that K-Ras 4B is targeted by lysine acetylation at K104. Based on results obtained for an acetylation mimetic Ras mutant (K104Q), it was hypothesised that K104-acetylation might interfere with its oncogenicity by impairing SOS-catalysed guanine-nucleotide exchange. We prepared site-specifically K104-acetylated K-Ras 4B and the corresponding oncogenic mutant protein G12V using the genetic-code expansion concept. We found that SOS-catalysed nucleotide exchange, also of allosterically activated SOS, was neither affected by acetylation of K104 in wildtype K-Ras 4B nor in the G12V mutant, suggesting that glutamine is a poor mimetic for acetylation at this site. In vitro, the lysine-acetyltransferases CBP and p300 were able to acetylate both, wildtype and G12V K-Ras 4B. In addition to K104 we identified further acetylation sites in K-Ras 4B, including K147, within the important G5/SAK-motif. However, the intrinsic and the SOS-catalysed nucleotide exchange was not affected by K147-acetylation of K-Ras 4B. Finally, we show that Sirt2 and HDAC6 do neither deacetylate K-Ras 4B if acetylated at K104 nor if acetylated at K147 in vitro.

  2. Acetylation of Gly1 and Lys2 Promotes Aggregation of Human γD-Crystallin

    PubMed Central

    2015-01-01

    The human lens contains three major protein families: α-, β-, and γ-crystallin. Among the several variants of γ-crystallin in the human lens, γD-crystallin is a major form. γD-Crystallin is primarily present in the nuclear region of the lens and contains a single lysine residue at the second position (K2). In this study, we investigated the acetylation of K2 in γD-crystallin in aging and cataractous human lenses. Our results indicated that K2 is acetylated at an early age and that the amount of K2-acetylated γD-crystallin increased with age. Mass spectrometric analysis revealed that in addition to K2, glycine 1 (G1) was acetylated in γD-crystallin from human lenses and in γD-crystallin acetylated in vitro. The chaperone ability of α-crystallin for acetylated γD-crystallin was lower than that for the nonacetylated protein. The tertiary structure and the microenvironment of the cysteine residues were significantly altered by acetylation. The acetylated protein exhibited higher surface hydrophobicity, was unstable against thermal and chemical denaturation, and exhibited a higher propensity to aggregate at 80 °C in comparison to the nonacetylated protein. Acetylation enhanced the GdnHCl-induced unfolding and slowed the subsequent refolding of γD-crystallin. Theoretical analysis indicated that the acetylation of K2 and G1 reduced the structural stability of the protein and brought the distal cysteine residues (C18 and C78) into close proximity. Collectively, these results indicate that the acetylation of G1 and K2 residues in γD-crystallin likely induced a molten globule-like structure, predisposing it to aggregation, which may account for the high content of aggregated proteins in the nucleus of aged and cataractous human lenses. PMID:25393041

  3. 3-Hydroxy-3-methylglutaryl-coenzyme A synthase from ox liver. Properties of its acetyl derivative.

    PubMed Central

    Lowe, D M; Tubbs, P K

    1985-01-01

    Ox liver mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (EC 4.1.3.5) reacts with acetyl-CoA to form a complex in which the acetyl group is covalently bound to the enzyme. This acetyl group can be removed by addition of acetoacetyl-CoA or CoA. The extent of acetylation and release of CoA were found to be highly temperature-dependent. At temperatures above 20 degrees C, a maximum value of 0.85 mol of acetyl group bound/mol of enzyme dimer was observed. Below this temperature the extent of rapid acetylation was significantly lowered. Binding stoichiometries close to 1 mol/mol of enzyme dimer were also observed when the 3-hydroxy-3-methylglutaryl-CoA synthase activity was titrated with methyl methanethiosulphonate or bromoacetyl-CoA. This is taken as evidence for a 'half-of-the-sites' reaction mechanism for the formation of 3-hydroxy-3-methylglutaryl-CoA by 3-hydroxy-3-methylglutaryl-CoA synthase. The Keq. for the acetylation was about 10. Isolated acetyl-enzyme is stable for many hours at 0 degrees C and pH 7, but is hydrolysed at 30 degrees C with a half-life of 7 min. This hydrolysis is stimulated by acetyl-CoA and slightly by succinyl-CoA, but not by desulpho-CoA. The site of acetylation has been identified as the thiol group of a reactive cysteine residue by affinity-labelling with the substrate analogue bromo[1-14C]acetyl-CoA. PMID:2860896

  4. Mutations of Arabidopsis TBL32 and TBL33 affect xylan acetylation and secondary wall deposition

    DOE PAGES

    Yuan, Youxi; Teng, Quincy; Zhong, Ruiqin; Haghighat, Marziyeh; Richardson, Elizabeth A.; Ye, Zheng -Hua; Zhang, Jin -Song

    2016-01-08

    Xylan is a major acetylated polymer in plant lignocellulosic biomass and it can be monoand di-acetylated at O-2 and O-3 as well as mono-acetylated at O-3 of xylosyl residues that is substituted with glucuronic acid (GlcA) at O-2. Based on the finding that ESK1, an Arabidopsis thaliana DUF231 protein, specifically mediates xylan 2-O- and 3-O-monoacetylation, we previously proposed that different acetyltransferase activities are required for regiospecific acetyl substitutions of xylan. Here, we demonstrate the functional roles of TBL32 and TBL33, two ESK1 close homologs, in acetyl substitutions of xylan. Simultaneous mutations of TBL32 and TBL33 resulted in a significant reductionmore » in xylan acetyl content and endoxylanase digestion of the mutant xylan released GlcA-substituted xylooligomers without acetyl groups. Structural analysis of xylan revealed that the tbl32 tbl33 mutant had a nearly complete loss of 3-O-acetylated, 2-O-GlcA-substituted xylosyl residues. A reduction in 3-Omonoacetylated and 2,3-di-O-acetylated xylosyl residues was also observed. Simultaneous mutations of TBL32, TBL33 and ESK1 resulted in a severe reduction in xylan acetyl level down to 15% of that of the wild type, and concomitantly, severely collapsed vessels and stunted plant growth. In particular, the S2 layer of secondary walls in xylem vessels of tbl33 esk1 and tbl32 tbl33 esk1 exhibited an altered structure, indicating abnormal assembly of secondary wall polymers. Furthermore, these results demonstrate that TBL32 and TBL33 play an important role in xylan acetylation and normal deposition of secondary walls.« less

  5. Acetylproteomic analysis reveals functional implications of lysine acetylation in human spermatozoa (sperm).

    PubMed

    Yu, Heguo; Diao, Hua; Wang, Chunmei; Lin, Yan; Yu, Fudong; Lu, Hui; Xu, Wei; Li, Zheng; Shi, Huijuan; Zhao, Shimin; Zhou, Yuchuan; Zhang, Yonglian

    2015-04-01

    Male infertility is a medical condition that has been on the rise globally. Lysine acetylation of human sperm, an essential posttranslational modification involved in the etiology of sperm abnormality, is not fully understood. Therefore, we first generated a qualified pan-anti-acetyllysine monoclonal antibody to characterize the global lysine acetylation of uncapacitated normal human sperm with a proteomics approach. With high enrichment ratios that were up to 31%, 973 lysine-acetylated sites that matched to 456 human sperm proteins, including 671 novel lysine acetylation sites and 205 novel lysine-acetylated proteins, were identified. These proteins exhibited conserved motifs XXXKYXXX, XXXKFXXX, and XXXKHXXX, were annotated to function in multiple metabolic processes, and were localized predominantly in the mitochondrion and cytoplasmic fractions. Between the uncapacitated and capacitated sperm, different acetylation profiles in regard to functional proteins involved in sperm capacitation, sperm-egg recognition, sperm-egg plasma fusion, and fertilization were observed, indicating that acetylation of functional proteins may be required during sperm capacitation. Bioinformatics analysis revealed association of acetylated proteins with diseases and drugs. Novel acetylation of voltage-dependent anion channel proteins was also found. With clinical sperm samples, we observed differed lysine acetyltransferases and lysine deacetylases expression between normal sperm and abnormal sperm of asthenospermia or necrospermia. Furthermore, with sperm samples impaired by epigallocatechin gallate to mimic asthenospermia, we observed that inhibition of sperm motility was partly through the blockade of voltage-dependent anion channel 2 Lys-74 acetylation combined with reduced ATP levels and mitochondrial membrane potential. Taken together, we obtained a qualified pan-anti-acetyllysine monoclonal antibody, analyzed the acetylproteome of uncapacitated human sperm, and revealed

  6. Acetylproteomic Analysis Reveals Functional Implications of Lysine Acetylation in Human Spermatozoa (sperm)*

    PubMed Central

    Yu, Heguo; Diao, Hua; Wang, Chunmei; Lin, Yan; Yu, Fudong; Lu, Hui; Xu, Wei; Li, Zheng; Shi, Huijuan; Zhao, Shimin; Zhou, Yuchuan; Zhang, Yonglian

    2015-01-01

    Male infertility is a medical condition that has been on the rise globally. Lysine acetylation of human sperm, an essential posttranslational modification involved in the etiology of sperm abnormality, is not fully understood. Therefore, we first generated a qualified pan-anti-acetyllysine monoclonal antibody to characterize the global lysine acetylation of uncapacitated normal human sperm with a proteomics approach. With high enrichment ratios that were up to 31%, 973 lysine-acetylated sites that matched to 456 human sperm proteins, including 671 novel lysine acetylation sites and 205 novel lysine-acetylated proteins, were identified. These proteins exhibited conserved motifs XXXKYXXX, XXXKFXXX, and XXXKHXXX, were annotated to function in multiple metabolic processes, and were localized predominantly in the mitochondrion and cytoplasmic fractions. Between the uncapacitated and capacitated sperm, different acetylation profiles in regard to functional proteins involved in sperm capacitation, sperm-egg recognition, sperm-egg plasma fusion, and fertilization were observed, indicating that acetylation of functional proteins may be required during sperm capacitation. Bioinformatics analysis revealed association of acetylated proteins with diseases and drugs. Novel acetylation of voltage-dependent anion channel proteins was also found. With clinical sperm samples, we observed differed lysine acetyltransferases and lysine deacetylases expression between normal sperm and abnormal sperm of asthenospermia or necrospermia. Furthermore, with sperm samples impaired by epigallocatechin gallate to mimic asthenospermia, we observed that inhibition of sperm motility was partly through the blockade of voltage-dependent anion channel 2 Lys-74 acetylation combined with reduced ATP levels and mitochondrial membrane potential. Taken together, we obtained a qualified pan-anti-acetyllysine monoclonal antibody, analyzed the acetylproteome of uncapacitated human sperm, and revealed

  7. Mutations of Arabidopsis TBL32 and TBL33 Affect Xylan Acetylation and Secondary Wall Deposition

    PubMed Central

    Yuan, Youxi; Teng, Quincy; Zhong, Ruiqin; Haghighat, Marziyeh; Richardson, Elizabeth A.; Ye, Zheng-Hua

    2016-01-01

    Xylan is a major acetylated polymer in plant lignocellulosic biomass and it can be mono- and di-acetylated at O-2 and O-3 as well as mono-acetylated at O-3 of xylosyl residues that is substituted with glucuronic acid (GlcA) at O-2. Based on the finding that ESK1, an Arabidopsis thaliana DUF231 protein, specifically mediates xylan 2-O- and 3-O-monoacetylation, we previously proposed that different acetyltransferase activities are required for regiospecific acetyl substitutions of xylan. Here, we demonstrate the functional roles of TBL32 and TBL33, two ESK1 close homologs, in acetyl substitutions of xylan. Simultaneous mutations of TBL32 and TBL33 resulted in a significant reduction in xylan acetyl content and endoxylanase digestion of the mutant xylan released GlcA-substituted xylooligomers without acetyl groups. Structural analysis of xylan revealed that the tbl32 tbl33 mutant had a nearly complete loss of 3-O-acetylated, 2-O-GlcA-substituted xylosyl residues. A reduction in 3-O-monoacetylated and 2,3-di-O-acetylated xylosyl residues was also observed. Simultaneous mutations of TBL32, TBL33 and ESK1 resulted in a severe reduction in xylan acetyl level down to 15% of that of the wild type, and concomitantly, severely collapsed vessels and stunted plant growth. In particular, the S2 layer of secondary walls in xylem vessels of tbl33 esk1 and tbl32 tbl33 esk1 exhibited an altered structure, indicating abnormal assembly of secondary wall polymers. These results demonstrate that TBL32 and TBL33 play an important role in xylan acetylation and normal deposition of secondary walls. PMID:26745802

  8. In vitro synthesis and O acetylation of peptidoglycan by permeabilized cells of Proteus mirabilis.

    PubMed Central

    Dupont, C; Clarke, A J

    1991-01-01

    The synthesis and O acetylation in vitro of peptidoglycan by Proteus mirabilis was studied in microorganisms made permeable to specifically radiolabelled nucleotide precursors by treatment with either diethyl ether or toluene. Optimum synthesis occurred with cells permeabilized by 1% (vol/vol) toluene in 30 mM MgCl2 in in vitro experiments with 50 mM Tris-HCl buffer (pH 6.80). Acetate recovered by mild base hydrolysis from sodium dodecyl sulfate-insoluble peptidoglycan synthesized in the presence of UDP-[acetyl-1-14C]N-acetyl-D-glucosamine was found to be radioactive. Radioactivity was not retained by peptidoglycan synthesized when UDP-[acetyl-1-14C]N-acetyl-D-glucosamine was replaced with both unlabelled nucleotide and either [acetyl-3H]N-acetyl-D-glucosamine or [glucosamine-1,6-3H]N-acetyl-D-glucosamine. In addition, no radioactive acetate was detected in the mild base hydrolysates of peptidoglycan synthesized in vitro with UDP-[glucosamine-6-3H]N-acetyl-D-glucosamine as the radiolabel. Chasing UDP-[acetyl-1-14C]N-acetyl-D-glucosamine with unlabelled material served to increase the yield of O-linked [14C]acetate, whereas penicillin G blocked both peptidoglycan synthesis and [14C]acetate transfer. These results support the hypothesis that the base-labile O-linked acetate is derived directly from N-acetylglucosamine incorporated into insoluble peptidoglycan via N----O transacetylation and not from the catabolism of the supplemented peptidoglycan precursors followed by subsequent reactivation of acetate. PMID:1856164

  9. Identification of the Acetylation and Ubiquitin-Modified Proteome during the Progression of Skeletal Muscle Atrophy

    PubMed Central

    Ryder, Daniel J.; Judge, Sarah M.; Beharry, Adam W.; Farnsworth, Charles L.; Silva, Jeffrey C.; Judge, Andrew R.

    2015-01-01

    Skeletal muscle atrophy is a consequence of several physiological and pathophysiological conditions including muscle disuse, aging and diseases such as cancer and heart failure. In each of these conditions, the predominant mechanism contributing to the loss of skeletal muscle mass is increased protein turnover. Two important mechanisms which regulate protein stability and degradation are lysine acetylation and ubiquitination, respectively. However our understanding of the skeletal muscle proteins regulated through acetylation and ubiquitination during muscle atrophy is limited. Therefore, the purpose of the current study was to conduct an unbiased assessment of the acetylation and ubiquitin-modified proteome in skeletal muscle during a physiological condition of muscle atrophy. To induce progressive, physiologically relevant, muscle atrophy, rats were cast immobilized for 0, 2, 4 or 6 days and muscles harvested. Acetylated and ubiquitinated peptides were identified via a peptide IP proteomic approach using an anti-acetyl lysine antibody or a ubiquitin remnant motif antibody followed by mass spectrometry. In control skeletal muscle we identified and mapped the acetylation of 1,326 lysine residues to 425 different proteins and the ubiquitination of 4,948 lysine residues to 1,131 different proteins. Of these proteins 43, 47 and 50 proteins were differentially acetylated and 183, 227 and 172 were differentially ubiquitinated following 2, 4 and 6 days of disuse, respectively. Bioinformatics analysis identified contractile proteins as being enriched among proteins decreased in acetylation and increased in ubiquitination, whereas histone proteins were enriched among proteins increased in acetylation and decreased in ubiquitination. These findings provide the first proteome-wide identification of skeletal muscle proteins exhibiting changes in lysine acetylation and ubiquitination during any atrophy condition, and provide a basis for future mechanistic studies into how the

  10. Affordability of alcohol and alcohol-related mortality in Belarus.

    PubMed

    Razvodovsky, Yury E

    2013-01-01

    Alcohol abuse has numerous adverse health and social consequences. The consumer response to changes in alcohol affordability is an important issue on alcohol policy debates. Studies from many countries have shown an inverse relationship between alcohol prices and alcohol consumption in the population. There are, however, suggestions that increasing the price of alcohol by rising taxes may have limited effect on alcohol-related problems, associated with long-term heavy drinking. The aim of the present study was to evaluate the relationship between alcohol affordability and alcohol-related mortality rates in post-Soviet Belarus. For this purpose trends in alcohol-related mortality rates (mortality from liver cirrhosis, pancreatitis, alcoholism and alcohol psychoses) and affordability of vodka between 1990 and 2010 were compared. The time series analysis revealed that 1% increase in vodka affordability is associated with an increase in liver cirrhosis mortality of 0,77%, an increase in pancreatitis mortality of 0.53%, an increase in mortality from alcoholism and alcohol psychoses of 0,70%. The major conclusion emerging from this study is that affordability of alcohol is one of the most important predictor of alcohol-related problems in a population. These findings provide additional evidence that decreasing in affordability of alcohol is an effective strategy for reducing alcohol consumption and alcohol-related harm.

  11. [Alcohol and criminal behavior].

    PubMed

    Arzt, G

    1990-05-01

    The topic 'alcohol and crime' has several aspects. This article shows how drug administration is based on a complex network of legal provisions and is enforced by criminal law sanctions. As to crimes influenced by alcohol, drunken driving is by far the most important and best researched field. Next, the article turns to the role of alcohol with regard to severe common crimes such as murder or child abuse. Finally, the issue of drunkenness as a defence is raised and the treatment of alcoholics as a criminal law sanction discussed.

  12. Alcohol disrupts sleep homeostasis

    PubMed Central

    Thakkar, Mahesh M.; Sharma, Rishi; Sahota, Pradeep

    2014-01-01

    Alcohol is a potent somnogen and one of the most commonly used “over the counter” sleep aids. In healthy non-alcoholics, acute alcohol decreases sleep latency, consolidates and increases the quality (delta power) and quantity of NREM sleep during the first half of the night. However, sleep is disrupted during the second half. Alcoholics, both during drinking periods and during abstinences, suffer from a multitude of sleep disruptions manifested by profound insomnia, excessive daytime sleepiness, and altered sleep architecture. Furthermore, subjective and objective indicators of sleep disturbances are predictors of relapse. Finally, within the USA, it is estimated that societal costs of alcohol-related sleep disorders exceeds $18 billion. Thus, although alcohol-associated sleep problems have significant economic and clinical consequences, very little is known about how and where alcohol acts to affect sleep. In this review, we have described our attempts to understand how and where alcohol acts to affect sleep. We have conducted a series of experiments using two different species, rats and mice, as animal models, and a combination of multi-disciplinary experimental methodologies to examine and understand anatomical and cellular substrates mediating the effects of acute and chronic alcohol exposure on sleep-wakefulness. The results of our studies suggest that the sleep-promoting effects of alcohol may be mediated via alcohol’s action on the mediators of sleep homeostasis: adenosine (AD) and the wake-promoting cholinergic neurons of the basal forebrain (BF). Alcohol, via its action on AD uptake, increases extracellular AD resulting in the inhibition of BF wake-promoting neurons. Lesions of the BF cholinergic neurons or blockade of AD A1 receptors results in attenuation of alcohol-induced sleep promotion, suggesting that AD and BF cholinergic neurons are critical for sleep-promoting effects of alcohol. Since binge alcohol consumption is a highly prevalent pattern

  13. Older Adults and Alcohol

    MedlinePlus

    ... Disorders Publications & Multimedia Brochures & Fact Sheets NIAAA Journal Alcohol Alert Bulletin Professional Education Materials Classroom Resources Presentations & Videocasts Video Bank Publicaciones ...

  14. Microwave alcohol fuel sensor

    SciTech Connect

    Kimura, K.; Endo, A.; Morozumi, H.; Shibata, T.

    1984-06-05

    A microwave alcohol fuel sensor comprises a microwave oscillator, a microwave receiver, and a microwave transmission circuit connected to the oscillator and the receiver. The microwave transmission circuit comprises a dielectric substrate and, a strip line mounted on the substrate so that microwaves leak from the substrate to an alcohol gasoline fuel, and the microwaves attenuate by alcohol dielectric loss, whereby output voltage from the receiver corresponds to alcohol content rate. The dielectric substrate is formed tubular so that a constant amount of the fuel is fed the sensor.

  15. Hepatocyte nuclear factor-1alpha is required for expression but dispensable for histone acetylation of the lactase-phlorizin hydrolase gene in vivo.

    PubMed

    Bosse, Tjalling; van Wering, Herbert M; Gielen, Marieke; Dowling, Lauren N; Fialkovich, John J; Piaseckyj, Christina M; Gonzalez, Frank J; Akiyama, Taro E; Montgomery, Robert K; Grand, Richard J; Krasinski, Stephen D

    2006-05-01

    Hepatocyte nuclear factor-1alpha (HNF-1alpha) is a modified homeodomain-containing transcription factor that has been implicated in the regulation of intestinal genes. To define the importance and underlying mechanism of HNF-1alpha for the regulation of intestinal gene expression in vivo, we analyzed the expression of the intestinal differentiation markers and putative HNF-1alpha targets lactase-phlorizin hydrolase (LPH) and sucrase-isomaltase (SI) in hnf1alpha null mice. We found that in adult jejunum, LPH mRNA in hnf1alpha(-/-) mice was reduced 95% compared with wild-type controls (P < 0.01, n = 4), whereas SI mRNA was virtually identical to that in wild-type mice. Furthermore, SI mRNA abundance was unchanged in the absence of HNF-1alpha along the length of the adult mouse small intestine as well as in newborn jejunum. We found that HNF-1alpha occupies the promoters of both the LPH and SI genes in vivo. However, in contrast to liver and pancreas, where HNF-1alpha regulates target genes by recruitment of histone acetyl transferase activity to the promoter, the histone acetylation state of the LPH and SI promoters was not affected by the presence or absence of HNF-1alpha. Finally, we showed that a subset of hypothesized intestinal target genes is regulated by HNF-1alpha in vivo and that this regulation occurs in a defined tissue-specific and developmental context. These data indicate that HNF-1alpha is an activator of a subset of intestinal genes and induces these genes through an alternative mechanism in which it is dispensable for chromatin remodeling.

  16. Purification and Characterization of the Staphylococcus aureus Bacillithiol Transferase BstA

    PubMed Central

    Perera, Varahenage R.; Newton, Gerald L.; Parnell, Jonathan M.; Komives, Elizabeth A.; Pogliano, Kit

    2016-01-01

    Background Gram-positive bacteria in the phylum Firmicutes synthesize the low molecular weight thiol bacillithiol rather than glutathione or mycothiol. The bacillithiol transferase YfiT from Bacillus subtilis was identified as a new member of the recently discovered DinB/YfiT-like Superfamily. Based on structural similarity using the Superfamily program, we have determined 30 of 31 Staphylococcus aureus strains encode a single bacillithiol transferase from the DinB/YfiT-like Superfamily, while the remaining strain encodes two proteins. Methods We have cloned, purified, and confirmed the activity of a recombinant bacillithiol transferase (henceforth called BstA) encoded by the S. aureus Newman ORF NWMN_2591. Moreover, we have studied the saturation kinetics and substrate specificity of this enzyme using in vitro biochemical assays. Results BstA was found to be active with the co-substrate bacillithiol, but not with other low molecular weight thiols tested. BstA catalyzed bacillithiol conjugation to the model substrates monochlorobimane, 1-chloro-2,4-dinitrobenzene, and the antibiotic cerulenin. Several other molecules, including the antibiotic rifamycin S, were found to react directly with bacillithiol, but the addition of BstA did not enhance the rate of reaction. Furthermore, cells growing in nutrient rich medium exhibited low BstA activity. Conclusions BstA is a bacillithiol transferase from Staphylococcus aureus that catalyzes the detoxification of cerulenin. Additionally, we have determined that bacillithiol itself might be capable of directly detoxifying electrophilic molecules. General Significance BstA is an active bacillithiol transferase from Staphylococcus aureus Newman and is the first DinB/YfiT-like Superfamily member identified from this organism. Interestingly, BstA is highly divergent from Bacillus subtilis YfiT. PMID:24821014

  17. Purification and characterization of an esterase involved in poly(vinyl alcohol) degradation by Pseudomonas vesicularis PD.

    PubMed

    Sakai, K; Fukuba, M; Hasui, Y; Moriyoshi, K; Ohmoto, T; Fujita, T; Ohe, T

    1998-10-01

    An esterase catalyzing the hydrolysis of acetyl ester moieties in poly(vinyl alcohol) was purified 400-fold to electrophoretic homogeneity from the cytoplasmic fraction of Pseudomonas vesicularis PD, which was capable of assimilating poly(vinyl alcohol) as the sole carbon and energy source. The purified enzyme was a homodimeric protein with a molecular mass of 80 kDa and the isoelectric point was 6.8. The pH and temperature optima of the enzyme were 8.0 and 45 degrees C. The enzyme catalyzed the hydrolysis of side chains of poly(vinyl alcohol), short-chain p-nitrophenyl esters, 2-naphthyl acetate, and phenyl acetate, and was slightly active toward aliphatic esters. The enzyme was also active toward the enzymatic degradation products, acetoxy hydroxy fatty acids, of poly(vinyl alcohol). The K(m) and Vmax of poly(vinyl alcohol) (degree of polymerization, 500; saponification degree, 86.5-89.0 mol%) and p-nitrophenyl acetate were 0.381% (10.6 mM as acetyl content in the polymer) and 2.56 microM, and 6.52 and 12.6 mumol/min/mg, respectively. The enzyme was strongly inhibited by phenylmethylsulfonyl fluoride and diisopropyl fluorophosphate at a concentration of 5 mM, which indicated that the enzyme was a serine esterase. The pathway for the metabolism of poly(vinyl alcohol) is also discussed.

  18. Identification of an Arabidopsis Fatty Alcohol:Caffeoyl-Coenzyme A Acyltransferase Required for the Synthesis of Alkyl Hydroxycinnamates in Root Waxes1[W][OA

    PubMed Central

    Kosma, Dylan K.; Molina, Isabel; Ohlrogge, John B.; Pollard, Mike

    2012-01-01

    While suberin is an insoluble heteropolymer, a number of soluble lipids can be extracted by rapid chloroform dipping of roots. These extracts include esters of saturated long-chain primary alcohols and hydroxycinnamic acids. Such fatty alcohols and hydroxycinnamic acids are also present in suberin. We demonstrate that alkyl coumarates and caffeates, which are the major components of Arabidopsis (Arabidopsis thaliana) root waxes, are present primarily in taproots. Previously we identified ALIPHATIC SUBERIN FERULOYL TRANSFERASE (At5g41040), a HXXXD-type acyltransferase (BAHD family), responsible for incorporation of ferulate into aliphatic suberin of Arabidopsis. However, aliphatic suberin feruloyl transferase mutants were unaffected in alkyl hydroxycinnamate ester root wax composition. Here we identify a closely related gene, At5g63560, responsible for the synthesis of a subset of alkyl hydroxycinnamate esters, the alkyl caffeates. Transgenic plants harboring PAt5g63560::YFP fusions showed transcriptional activity in suberized tissues. Knockout mutants of At5g63560 were severely reduced in their alkyl caffeate but not alkyl coumarate content. Recombinant At5g63560p had greater acyltransferase activity when presented with caffeoyl-Coenzyme A (CoA) substrate, thus we have named this acyltransferase FATTY ALCOHOL:CAFFEOYL-CoA CAFFEOYL TRANSFERASE. Stress experiments revealed elevated alkyl coumarate content in root waxes of NaCl-treated wild-type and fatty alcohol:caffeoyl-CoA caffeoyl transferase plants. We further demonstrate that FATTY ACYL-CoA REDUCTASEs (FARs) FAR5 (At3g44550), FAR4 (At3g44540), and FAR1 (At5g22500) are required for the synthesis of C18, C20, and C22 alkyl hydroxycinnamates, respectively. Collectively, these results suggest that multiple acyltransferases are utilized for the synthesis of alkyl hydroxycinnamate esters of Arabidopsis root waxes and that FAR1/4/5 provide the fatty alcohols required for alkyl hydroxycinnamate synthesis. PMID:22797656

  19. Identification of an Arabidopsis fatty alcohol:caffeoyl-Coenzyme A acyltransferase required for the synthesis of alkyl hydroxycinnamates in root waxes.

    PubMed

    Kosma, Dylan K; Molina, Isabel; Ohlrogge, John B; Pollard, Mike

    2012-09-01

    While suberin is an insoluble heteropolymer, a number of soluble lipids can be extracted by rapid chloroform dipping of roots. These extracts include esters of saturated long-chain primary alcohols and hydroxycinnamic acids. Such fatty alcohols and hydroxycinnamic acids are also present in suberin. We demonstrate that alkyl coumarates and caffeates, which are the major components of Arabidopsis (Arabidopsis thaliana) root waxes, are present primarily in taproots. Previously we identified ALIPHATIC SUBERIN FERULOYL TRANSFERASE (At5g41040), a HXXXD-type acyltransferase (BAHD family), responsible for incorporation of ferulate into aliphatic suberin of Arabidopsis. However, aliphatic suberin feruloyl transferase mutants were unaffected in alkyl hydroxycinnamate ester root wax composition. Here we identify a closely related gene, At5g63560, responsible for the synthesis of a subset of alkyl hydroxycinnamate esters, the alkyl caffeates. Transgenic plants harboring P(At5g63560)::YFP fusions showed transcriptional activity in suberized tissues. Knockout mutants of At5g63560 were severely reduced in their alkyl caffeate but not alkyl coumarate content. Recombinant At5g63560p had greater acyltransferase activity when presented with caffeoyl-Coenzyme A (CoA) substrate, thus we have named this acyltransferase FATTY ALCOHOL:CAFFEOYL-CoA CAFFEOYL TRANSFERASE. Stress experiments revealed elevated alkyl coumarate content in root waxes of NaCl-treated wild-type and fatty alcohol:caffeoyl-CoA caffeoyl transferase plants. We further demonstrate that FATTY ACYL-CoA REDUCTASEs (FARs) FAR5 (At3g44550), FAR4 (At3g44540), and FAR1 (At5g22500) are required for the synthesis of C18, C20, and C22 alkyl hydroxycinnamates, respectively. Collectively, these results suggest that multiple acyltransferases are utilized for the synthesis of alkyl hydroxycinnamate esters of Arabidopsis root waxes and that FAR1/4/5 provide the fatty alcohols required for alkyl hydroxycinnamate synthesis.

  20. Prenatal alcohol consumption and knowledge about alcohol consumption and fetal alcohol syndrome in Korean women.

    PubMed

    Kim, Oksoo; Park, Kyungil

    2011-09-01

    The study investigated prenatal alcohol consumption and knowledge of alcohol risks and fetal alcohol syndrome among Korean women. The participants were 221 Korean women who attended the post-partum care centers in Seoul, Korea. The data included the participants' background characteristics, quantity-frequency typology, Student Alcohol Questionnaire, and a scale on the participants' knowledge of fetal alcohol syndrome. Alcohol was consumed during pregnancy by 12.7% of the participants. Of these, 60.7% drank alcohol with their spouse. A few participants reported that nurses identified their drinking habits and gave them information on alcohol consumption and fetal alcohol syndrome. Most of the participants did not have the opportunity for prenatal counseling about fetal alcohol syndrome. The knowledge level regarding alcohol risks and fetal alcohol syndrome among the participants was poor. Alcohol consumption before pregnancy was significantly related to prenatal alcohol consumption. Prenatal alcohol consumption was not related to knowledge about alcohol consumption and fetal alcohol syndrome. The assessment of alcohol consumption and counseling about alcohol are needed for pregnant women in order to prevent fetal alcohol syndrome.

  1. Identification and characteristics of the structural gene for the Drosophila eye colour mutant sepia, encoding PDA synthase, a member of the omega class glutathione S-transferases.

    PubMed

    Kim, Jaekwang; Suh, Hyunsuk; Kim, Songhee; Kim, Kiyoung; Ahn, Chiyoung; Yim, Jeongbin

    2006-09-15

    The eye colour mutant sepia (se1) is defective in PDA {6-acetyl-2-amino-3,7,8,9-tetrahydro-4H-pyrimido[4,5-b]-[1,4]diazepin-4-one or pyrimidodiazepine} synthase involved in the conversion of 6-PTP (2-amino-4-oxo-6-pyruvoyl-5,6,7,8-tetrahydropteridine; also known as 6-pyruvoyltetrahydropterin) into PDA, a key intermediate in drosopterin biosynthesis. However, the identity of the gene encoding this enzyme, as well as its molecular properties, have not yet been established. Here, we identify and characterize the gene encoding PDA synthase and show that it is the structural gene for sepia. Based on previously reported information [Wiederrecht, Paton and Brown (1984) J. Biol. Chem. 259, 2195-2200; Wiederrecht and Brown (1984) J. Biol. Chem. 259, 14121-14127; Andres (1945) Drosoph. Inf. Serv. 19, 45; Ingham, Pinchin, Howard and Ish-Horowicz (1985) Genetics 111, 463-486; Howard, Ingham and Rushlow (1988) Genes Dev. 2, 1037-1046], we isolated five candidate genes predicted to encode GSTs (glutathione S-transferases) from the presumed sepia locus (region 66D5 on chromosome 3L). All cloned and expressed candidates exhibited relatively high thiol transferase and dehydroascorbate reductase activities and low activity towards 1-chloro-2,4-dinitrobenzene, characteristic of Omega class GSTs, whereas only CG6781 catalysed the synthesis of PDA in vitro. The molecular mass of recombinant CG6781 was estimated to be 28 kDa by SDS/PAGE and 56 kDa by gel filtration, indicating that it is a homodimer under native conditions. Sequencing of the genomic region spanning CG6781 revealed that the se1 allele has a frameshift mutation from 'AAGAA' to 'GTG' at nt 190-194, and that this generates a premature stop codon. Expression of the CG6781 open reading frame in an se1 background rescued the eye colour defect as well as PDA synthase activity and drosopterins content. The extent of rescue was dependent on the dosage of transgenic CG6781. In conclusion, we have discovered a new catalytic

  2. Identification and characteristics of the structural gene for the Drosophila eye colour mutant sepia, encoding PDA synthase, a member of the omega class glutathione S-transferases.

    PubMed

    Kim, Jaekwang; Suh, Hyunsuk; Kim, Songhee; Kim, Kiyoung; Ahn, Chiyoung; Yim, Jeongbin

    2006-09-15

    The eye colour mutant sepia (se1) is defective in PDA {6-acetyl-2-amino-3,7,8,9-tetrahydro-4H-pyrimido[4,5-b]-[1,4]diazepin-4-one or pyrimidodiazepine} synthase involved in the conversion of 6-PTP (2-amino-4-oxo-6-pyruvoyl-5,6,7,8-tetrahydropteridine; also known as 6-pyruvoyltetrahydropterin) into PDA, a key intermediate in drosopterin biosynthesis. However, the identity of the gene encoding this enzyme, as well as its molecular properties, have not yet been established. Here, we identify and characterize the gene encoding PDA synthase and show that it is the structural gene for sepia. Based on previously reported information [Wiederrecht, Paton and Brown (1984) J. Biol. Chem. 259, 2195-2200; Wiederrecht and Brown (1984) J. Biol. Chem. 259, 14121-14127; Andres (1945) Drosoph. Inf. Serv. 19, 45; Ingham, Pinchin, Howard and Ish-Horowicz (1985) Genetics 111, 463-486; Howard, Ingham and Rushlow (1988) Genes Dev. 2, 1037-1046], we isolated five candidate genes predicted to encode GSTs (glutathione S-transferases) from the presumed sepia locus (region 66D5 on chromosome 3L). All cloned and expressed candidates exhibited relatively high thiol transferase and dehydroascorbate reductase activities and low activity towards 1-chloro-2,4-dinitrobenzene, characteristic of Omega class GSTs, whereas only CG6781 catalysed the synthesis of PDA in vitro. The molecular mass of recombinant CG6781 was estimated to be 28 kDa by SDS/PAGE and 56 kDa by gel filtration, indicating that it is a homodimer under native conditions. Sequencing of the genomic region spanning CG6781 revealed that the se1 allele has a frameshift mutation from 'AAGAA' to 'GTG' at nt 190-194, and that this generates a premature stop codon. Expression of the CG6781 open reading frame in an se1 background rescued the eye colour defect as well as PDA synthase activity and drosopterins content. The extent of rescue was dependent on the dosage of transgenic CG6781. In conclusion, we have discovered a new catalytic

  3. Identification and Characterization of Mitochondrial Acetyl-Coenzyme A Hydrolase from Pisum sativum L. Seedlings 1

    PubMed Central

    Zeiher, Carolyn A.; Randall, Douglas D.

    1990-01-01

    Mitochondria from Pisum sativum seedlings purified free of peroxisomal and chlorophyll contamination were examined for acetyl-coenzyme A (CoA) hydrolase activity. Acetyl-CoA hydrolase activity was latent when assayed in isotonic media. The majority of the enzyme activity was found in the soluble matrix of the mitochondria. The products, acetate and CoA, were quantified by two independent methods and verified that the observed activity was an acetyl-CoA hydrolase. The pea mitochondrial acetyl-CoA hydrolase showed a Km for acetyl-CoA of 74 micromolar and a Vmax of 6.1 nanomoles per minute per milligram protein. CoA was a linear competitive inhibitor of the enzyme with a Kis of 16 micromolar. The sensitivity of the enzyme to changes in mole fraction of acetyl-CoA suggested that the changes in the intramitochondrial acetyl-CoA/CoA ratio may be an effective mechanism of control. The widespread distribution of mitochondrial acetyl-CoA hydrolase activity among different plant species indicated that this may be a general mechanism in plants for synthesizing acetate. PMID:16667687

  4. N-Ace: using solvent accessibility and physicochemical properties to identify protein N-acetylation sites.

    PubMed

    Lee, Tzong-Yi; Hsu, Justin Bo-Kai; Lin, Feng-Mao; Chang, Wen-Chi; Hsu, Po-Chiang; Huang, Hsien-Da

    2010-11-30

    Protein acetylation, which is catalyzed by acetyltransferases, is a type of post-translational modification and crucial to numerous essential biological processes, including transcriptional regulation, apoptosis, and cytokine signaling. As the experimental identification of protein acetylation sites is time consuming and laboratory intensive, several computational approaches have been developed for identifying the candidates of experimental validation. In this work, solvent accessibility and the physicochemical properties of proteins are utilized to identify acetylated alanine, glycine, lysine, methionine, serine, and threonine. A two-stage support vector machine was applied to learn the computational models with combinations of amino acid sequences, and the accessible surface area and physicochemical properties of proteins. The predictive accuracy thus achieved is 5% to 14% higher than that of models trained using only amino acid sequences. Additionally, the substrate specificity of the acetylated site was investigated in detail with reference to the subcellular colocalization of acetyltransferases and acetylated proteins. The proposed method, N-Ace, is evaluated using independent test sets in various acetylated residues and predictive accuracies of 90% were achieved, indicating that the performance of N-Ace is comparable with that of other acetylation prediction methods. N-Ace not only provides a user-friendly input/output interface but also is a creative method for predicting protein acetylation sites. This novel analytical resource is now freely available at http://N-Ace.mbc.NCTU.edu.tw/. PMID:20839302

  5. The Effect of Acetyl-L-Carnitine Administration on Persons with Down Syndrome

    ERIC Educational Resources Information Center

    Pueschel, Siegfried M.

    2006-01-01

    Since previous investigations reported improvements in cognition of patients with dementia after acetyl-L-carnitine therapy and since there is an increased risk for persons with Down syndrome to develop Alzheimer disease, this study was designed to investigate the effect of acetyl-L-carnitine administration on neurological, intellectual, and…

  6. Requirements for Carnitine Shuttle-Mediated Translocation of Mitochondrial Acetyl Moieties to the Yeast Cytosol

    PubMed Central

    van Rossum, Harmen M.; Kozak, Barbara U.; Niemeijer, Matthijs S.; Dykstra, James C.; Luttik, Marijke A. H.; van Maris, Antonius J. A.

    2016-01-01

    ABSTRACT In many eukaryotes, the carnitine shuttle plays a key role in intracellular transport of acyl moieties. Fatty acid-grown Saccharomyces cerevisiae cells employ this shuttle to translocate acetyl units into their mitochondria. Mechanistically, the carnitine shuttle should be reversible, but previous studies indicate that carnitine shuttle-mediated export of mitochondrial acetyl units to the yeast cytosol does not occur in vivo. This apparent unidirectionality was investigated by constitutively expressing genes encoding carnitine shuttle-related proteins in an engineered S. cerevisiae strain, in which cytosolic acetyl coenzyme A (acetyl-CoA) synthesis could be switched off by omitting lipoic acid from growth media. Laboratory evolution of this strain yielded mutants whose growth on glucose, in the absence of lipoic acid, was l-carnitine dependent, indicating that in vivo export of mitochondrial acetyl units to the cytosol occurred via the carnitine shuttle. The mitochondrial pyruvate dehydrogenase complex was identified as the predominant source of acetyl-CoA in the evolved strains. Whole-genome sequencing revealed mutations in genes involved in mitochondrial fatty acid synthesis (MCT1), nuclear-mitochondrial communication (RTG2), and encoding a carnitine acetyltransferase (YAT2). Introduction of these mutations into the nonevolved parental strain enabled l-carnitine-dependent growth on glucose. This study indicates intramitochondrial acetyl-CoA concentration and constitutive expression of carnitine shuttle genes as key factors in enabling in vivo export of mitochondrial acetyl units via the carnitine shuttle. PMID:27143389

  7. A bioinformatics-based overview of protein Lys-Ne-acetylation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Among posttranslational modifications, there are some conceptual similarities between Lys-N'-acetylation and Ser/Thr/Tyr O-phosphorylation. Herein we present a bioinformatics-based overview of reversible protein Lys-acetylation, including some comparisons with reversible protein phosphorylation. T...

  8. Histone Acetylation is Recruited in Consolidation as a Molecular Feature of Stronger Memories

    ERIC Educational Resources Information Center

    Federman, Noel; Fustinana, Maria Sol; Romano, Arturo

    2009-01-01

    Gene expression is a key process for memory consolidation. Recently, the participation of epigenetic mechanisms like histone acetylation was evidenced in long-term memories. However, until now the training strength required and the persistence of the chromatin acetylation recruited are not well characterized. Here we studied whether histone…

  9. Acetylation of Starch with Vinyl Acetate in Imidazolium Ionic Liquids and Characterization of Acetate Distribution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Starch was acetylated with vinyl acetate in different 1-butyl-3-methylimidazolium (BMIM) salts as solvent in effort to produce starches with different acetylation patterns. Overall degree of substitution was much higher for basic anions such as acetate and dicyanimide (dca) than for neutral anions ...

  10. Protective Effects of Acetylation on the Pathological Reactions of the Lens Crystallins with Homocysteine Thiolactone

    PubMed Central

    Moafian, Zeinab; Khoshaman, Kazem; Oryan, Ahmad; Kurganov, Boris I.; Yousefi, Reza

    2016-01-01

    Various post-translational lens crystallins modifications result in structural and functional insults, contributing to the development of lens opacity and cataract disorders. Lens crystallins are potential targets of homocysteinylation, particularly under hyperhomocysteinemia which has been indicated in various eye diseases. Since both homocysteinylation and acetylation primarily occur on protein free amino groups, we applied different spectroscopic methods and gel mobility shift analysis to examine the possible preventive role of acetylation against homocysteinylation. Lens crystallins were extensively acetylated in the presence of acetic anhydride and then subjected to homocysteinylation in the presence of homocysteine thiolactone (HCTL). Extensive acetylation of the lens crystallins results in partial structural alteration and enhancement of their stability, as well as improvement of α-crystallin chaperone-like activity. In addition, acetylation partially prevents HCTL-induced structural alteration and aggregation of lens crystallins. Also, acetylation protects against HCTL-induced loss of α-crystallin chaperone activity. Additionally, subsequent acetylation and homocysteinylation cause significant proteolytic degradation of crystallins. Therefore, further experimentation is required in order to judge effectively the preventative role of acetylation on the structural and functional insults induced by homocysteinylation of lens crystallins. PMID:27706231

  11. An Artificial Reaction Promoter Modulates Mitochondrial Functions via Chemically Promoting Protein Acetylation

    PubMed Central

    Shindo, Yutaka; Komatsu, Hirokazu; Hotta, Kohji; Ariga, Katsuhiko; Oka, Kotaro

    2016-01-01

    Acetylation, which modulates protein function, is an important process in intracellular signalling. In mitochondria, protein acetylation regulates a number of enzymatic activities and, therefore, modulates mitochondrial functions. Our previous report showed that tributylphosphine (PBu3), an artificial reaction promoter that promotes acetylransfer reactions in vitro, also promotes the reaction between acetyl-CoA and an exogenously introduced fluorescent probe in mitochondria. In this study, we demonstrate that PBu3 induces the acetylation of mitochondrial proteins and a decrease in acetyl-CoA concentration in PBu3-treated HeLa cells. This indicates that PBu3 can promote the acetyltransfer reaction between acetyl-CoA and mitochondrial proteins in living cells. PBu3-induced acetylation gradually reduced mitochondrial ATP concentrations in HeLa cells without changing the cytoplasmic ATP concentration, suggesting that PBu3 mainly affects mitochondrial functions. In addition, pyruvate, which is converted into acetyl-CoA in mitochondria and transiently increases ATP concentrations in the absence of PBu3, elicited a further decrease in mitochondrial ATP concentrations in the presence of PBu3. Moreover, the application and removal of PBu3 reversibly alternated mitochondrial fragmentation and elongation. These results indicate that PBu3 enhances acetyltransfer reactions in mitochondria and modulates mitochondrial functions in living cells. PMID:27374857

  12. Protein acetylation affects acetate metabolism, motility and acid stress response in Escherichia coli

    PubMed Central

    Castaño-Cerezo, Sara; Bernal, Vicente; Post, Harm; Fuhrer, Tobias; Cappadona, Salvatore; Sánchez-Díaz, Nerea C; Sauer, Uwe; Heck, Albert JR; Altelaar, AF Maarten; Cánovas, Manuel

    2014-01-01

    Although protein acetylation is widely observed, it has been associated with few specific regulatory functions making it poorly understood. To interrogate its functionality, we analyzed the acetylome in Escherichia coli knockout mutants of cobB, the only known sirtuin-like deacetylase, and patZ, the best-known protein acetyltransferase. For four growth conditions, more than 2,000 unique acetylated peptides, belonging to 809 proteins, were identified and differentially quantified. Nearly 65% of these proteins are related to metabolism. The global activity of CobB contributes to the deacetylation of a large number of substrates and has a major impact on physiology. Apart from the regulation of acetyl-CoA synthetase, we found that CobB-controlled acetylation of isocitrate lyase contributes to the fine-tuning of the glyoxylate shunt. Acetylation of the transcription factor RcsB prevents DNA binding, activating flagella biosynthesis and motility, and increases acid stress susceptibility. Surprisingly, deletion of patZ increased acetylation in acetate cultures, which suggests that it regulates the levels of acetylating agents. The results presented offer new insights into functional roles of protein acetylation in metabolic fitness and global cell regulation. PMID:25518064

  13. Microbial conversion of daunorubicin into N-acetyl-13(S)-dihydrodaunomycin and bisanhydro-13-dihydrodaunomycinone.

    PubMed

    Dornberger, K; Hübener, R; Ihn, W; Thrum, H; Radics, L

    1985-09-01

    By using a strain of Streptomyces willmorii, daunorubicin (daunomycin) was stereoselectively converted into N-acetyl-13(S)-dihydrodaunomycin and bisanhydro-13-dihydrodaunomycinone. The absolute stereochemistry of the new chiral center in N-acetyl-13(S)-dihydrodaunomycin was established by means of nuclear Overhauser effect measured in the 9,13-O-isopropylidene derivative.

  14. A dysregulated acetyl/SUMO switch of FXR promotes hepatic inflammation in obesity

    PubMed Central

    Kim, Dong-Hyun; Xiao, Zhen; Kwon, Sanghoon; Sun, Xiaoxiao; Ryerson, Daniel; Tkac, David; Ma, Ping; Wu, Shwu-Yuan; Chiang, Cheng-Ming; Zhou, Edward; Xu, H Eric; Palvimo, Jorma J; Chen, Lin-Feng; Kemper, Byron; Kemper, Jongsook Kim

    2015-01-01

    Acetylation of transcriptional regulators is normally dynamically regulated by nutrient status but is often persistently elevated in nutrient-excessive obesity conditions. We investigated the functional consequences of such aberrantly elevated acetylation of the nuclear receptor FXR as a model. Proteomic studies identified K217 as the FXR acetylation site in diet-induced obese mice. In vivo studies utilizing acetylation-mimic and acetylation-defective K217 mutants and gene expression profiling revealed that FXR acetylation increased proinflammatory gene expression, macrophage infiltration, and liver cytokine and triglyceride levels, impaired insulin signaling, and increased glucose intolerance. Mechanistically, acetylation of FXR blocked its interaction with the SUMO ligase PIASy and inhibited SUMO2 modification at K277, resulting in activation of inflammatory genes. SUMOylation of agonist-activated FXR increased its interaction with NF-κB but blocked that with RXRα, so that SUMO2-modified FXR was selectively recruited to and trans-repressed inflammatory genes without affecting FXR/RXRα target genes. A dysregulated acetyl/SUMO switch of FXR in obesity may serve as a general mechanism for diminished anti-inflammatory response of other transcriptional regulators and provide potential therapeutic and diagnostic targets for obesity-related metabolic disorders. PMID:25425577

  15. Location of the O-acetyl substituents on a nonasaccharide repeating unit of sycamore extracellular xyloglucan.

    PubMed

    York, W S; Oates, J E; van Halbeek, H; Darvill, A G; Albersheim, P; Tiller, P R; Dell, A

    1988-02-15

    The locations of the O-acetyl substituents on the major nonasaccharide repeating unit of the xyloglucan isolated from sycamore extracellular polysaccharides were determined by a combination of analytical methods, including f.a.b.-m.s. and 1H-n.m.r. spectroscopy. The O-2-linked-beta-D-galactosyl residue of the nonasaccharide was found to be the dominant site of O-acetyl substitution. Both mono-O-acetylated and di-O-acetylated beta-D-galactosyl residues were detected. The degree of O-acetylation of the beta-D-galactosyl residue, was estimated by 1H-n.m.r. spectroscopy to be 55-60% at O-6, 15-20% at O-4, and 20-25% at O-3. 1H-n.m.r. spectroscopy also indicated that approximately 50% of the beta-D-galactosyl residues are mono-O-acetylated, 25-30% are di-O-acetylated, and 20% are not acetylated.

  16. Roles of Arabidopsis TBL34 and TBL35 in xylan acetylation and plant growth.

    PubMed

    Yuan, Youxi; Teng, Quincy; Zhong, Ruiqin; Ye, Zheng-Hua

    2016-02-01

    Xylan is one of the major polymers in lignocellulosic biomass and about 60% of its xylosyl residues are acetylated at O-2 and/or O-3. Because acetylation of cell wall polymers contributes to biomass recalcitrance for biofuel production, it is important to investigate the biochemical mechanism underlying xylan acetylation, the knowledge of which could be applied to custom-design biomass composition tailored for biofuel production. In this report, we investigated the functions of Arabidopsis TRICHOME BIREFRINGENCE-LIKE 34 (TBL34) and TBL35, two DUF231-containing proteins, in xylan acetylation. The TBL34 gene was found to be specifically expressed in xylem cells in stems and root-hypocotyls, and both TBL34 and TBL35 were shown to be localized in the Golgi, where xylan biosynthesis occurs. Chemical analysis revealed that simultaneous mutations of TBL34 and TBL35 caused a mild decrease in xylan acetyl content and a specific reduction in xylan 3-O-monoacetylation and 2,3-di-O-acetylation. Furthermore, simultaneous mutations of TBL34, TBL35 and ESKIMO1 (ESK1) resulted in severely collapsed xylem vessels with altered secondary wall structure, and an extremely retarded plant growth. These findings indicate that TBL34 and TBL35 are putative acetyltransferases required for xylan 3-O-monoacetylation and 2,3-di-O-acetylation and that xylan acetylation is essential for normal secondary wall deposition and plant growth. PMID:26795157

  17. Lysine acetylation stabilizes SP2 protein in the silkworm Bombyx mori.

    PubMed

    Zhou, Yong; Wu, Chengcheng; Sheng, Qing; Jiang, Caiying; Chen, Qin; Lv, Zhengbing; Yao, Juming; Nie, Zuoming

    2016-01-01

    Lysine acetylation (Kac) is a vital post-translational modification that plays an important role in many cellular processes in organisms. In the present study, the nutrient storage proteins in hemolymph were first found to be highly acetylated-particularly SP2 protein, which contains 20 potential Kac sites. Further results confirmed that lysine acetylation could stabilize and up-regulate the protein level of anti-apoptosis protein SP2, thereby improving the survival of H2O2-treated BmN cells and suppressing the apoptosis induced by H2O2. The potential mechanism involved in the inhibition of ubiquitin-mediated proteasomal degradation by crosstalk between lysine acetylation and ubiquitination. Our results showed that the increase in the acetylation level by TSA could decrease the ubiquitination and improve the protein level of SP2, indicating that lysine acetylation could influence the SP2 protein level through competition between ubiquitination and the suppression of ubiquitin-mediated proteasomal degradation, thereby stabilizing the protein. SP2 is a major nutrient storage protein from hemolymph for amino acid storage and utilization. The crosstalk between lysine acetylation and ubiquitination of SP2 might imply an important role of lysine acetylation for nutrient storage and utilization in silkworm. PMID:27374983

  18. Effects of acetylation on the emulsifying properties of Artemisia sphaerocephala Krasch. polysaccharide.

    PubMed

    Li, Junjun; Hu, Xinzhong; Li, Xiaoping; Ma, Zhen

    2016-06-25

    In the present study, polysaccharides extracted from Artemisia sphaerocephala Krasch. seeds (ASKP) were acetylated to improve the emulsifying properties of the macromolecules. Several methods were applied for the acetylation purpose, among which the acetic anhydride-pyridine method with formamide as solvent was found to be the most effective one. Acetylated ASKPs with various degree of substitution (DS) were successfully produced and structurally characterized using HPSEC-MALS, FTIR and (1)H NMR techniques in this study. Results showed that acetylation treatment could cause the degradation of ASKP. Moreover, with the increase of DS, both the molecular weight and radius of gyration increased, as well as the molecular conformation trended to be more compact. Low DS (DS: 0.04 and 0.13) conferred acetylated ASKP a lower viscosity than that of ASKP. With the increase of DS, the viscosity of acetylated ASKPs increased and exceeded that of ASKP. Compared with ASKP, acetylated ASKPs could reduce the surface tension to a greater extent and demonstrated a much smaller droplet size (ZD) in an oil/water emulsion system. Acetylated ASKPs were capable of stabilizing the oil/water emulsion for 3 days at 60°C, whose performance was as good as that of gum acacia. In conclusion, such a hydrophobic modification on ASKP conferred it better emulsifying properties. PMID:27083845

  19. Loss-of-Function Mutation of REDUCED WALL ACETYLATION2 in Arabidopsis Leads to Reduced Cell Wall Acetylation and Increased Resistance to Botrytis cinerea1[W][OA

    PubMed Central

    Manabe, Yuzuki; Nafisi, Majse; Verhertbruggen, Yves; Orfila, Caroline; Gille, Sascha; Rautengarten, Carsten; Cherk, Candice; Marcus, Susan E.; Somerville, Shauna; Pauly, Markus; Knox, J. Paul; Sakuragi, Yumiko; Scheller, Henrik Vibe

    2011-01-01

    Nearly all polysaccharides in plant cell walls are O-acetylated, including the various pectic polysaccharides and the hemicelluloses xylan, mannan, and xyloglucan. However, the enzymes involved in the polysaccharide acetylation have not been identified. While the role of polysaccharide acetylation in vivo is unclear, it is known to reduce biofuel yield from lignocellulosic biomass by the inhibition of microorganisms used for fermentation. We have analyzed four Arabidopsis (Arabidopsis thaliana) homologs of the protein Cas1p known to be involved in polysaccharide O-acetylation in Cryptococcus neoformans. Loss-of-function mutants in one of the genes, designated REDUCED WALL ACETYLATION2 (RWA2), had decreased levels of acetylated cell wall polymers. Cell wall material isolated from mutant leaves and treated with alkali released about 20% lower amounts of acetic acid when compared with the wild type. The same level of acetate deficiency was found in several pectic polymers and in xyloglucan. Thus, the rwa2 mutations affect different polymers to the same extent. There were no obvious morphological or growth differences observed between the wild type and rwa2 mutants. However, both alleles of rwa2 displayed increased tolerance toward the necrotrophic fungal pathogen Botrytis cinerea. PMID:21212300

  20. Alcohol-Related Liver Disease

    MedlinePlus

    ... to run events. Please support us. Donate | Volunteer Alcohol-Related Liver Disease Discussion on Inspire Support Community ... Liver > Liver Disease Information > Alcohol-Related Liver Disease Alcohol-Related Liver Disease Explore this section to learn ...

  1. Residues in the acetyl CoA binding site of pyruvate carboxylase involved in allosteric regulation.

    PubMed

    Choosangtong, Kamonman; Sirithanakorn, Chaiyos; Adina-Zada, Abdul; Wallace, John C; Jitrapakdee, Sarawut; Attwood, Paul V

    2015-07-22

    We have examined the roles of Asp1018, Glu1027, Arg469 and Asp471 in the allosteric domain of Rhizobium etli pyruvate carboxylase. Arg469 and Asp471 interact directly with the allosteric activator acetyl coenzyme A (acetyl CoA) and the R469S and R469K mutants showed increased enzymic activity in the presence and absence of acetyl CoA, whilst the D471A mutant exhibited no acetyl CoA-activation. E1027A, E1027R and D1018A mutants had increased activity in the absence of acetyl CoA, but not in its presence. These results suggest that most of these residues impose restrictions on the structure and/or dynamics of the enzyme to affect activity. PMID:26149215

  2. Improving the O/W emusifying properties of rapeseed lecithin ethanol insoluble fraction by acetylation.

    PubMed

    Sosada, Marian; Pasker, Beata; Bogocz, Marzena

    2003-01-01

    The effect of acetylation of rapeseed lecithin ethanol insoluble fraction (LEIF) containing 25% phosphatidylethanolamine (PE) on the O/W emulsifying properties was reported. In the study, acetic anhydride (50-150 mmol/100 g) and pyridine (0-30 mmole/100 g) were used. The PE conversion to N-acetyl-PE in LEIF determined by the HPLC method was varied from 18.2 to 84.7% and depended essentially on the acetylating agent amount and pyridine quantity used in acetylation. Emulsions of the O/W systems containing lecithin emulsifiers with different PE conversion degree were prepared and evaluated for its stability. It was found that the acetylation of LEIF improves its emulsifying properties and in the formation of emulsions containing soya oil, provided a decrease in oil droplet size and polydispersity index.

  3. Effect of Acetyl Group on Mechanical Properties of Chitin/Chitosan Nanocrystal: A Molecular Dynamics Study

    PubMed Central

    Cui, Junhe; Yu, Zechuan; Lau, Denvid

    2016-01-01

    Chitin fiber is the load-bearing component in natural chitin-based materials. In these materials, chitin is always partially deacetylated to different levels, leading to diverse material properties. In order to understand how the acetyl group enhances the fracture resistance capability of chitin fiber, we constructed atomistic models of chitin with varied acetylation degree and analyzed the hydrogen bonding pattern, fracture, and stress-strain behavior of these models. We notice that the acetyl group can contribute to the formation of hydrogen bonds that can stabilize the crystalline structure. In addition, it is found that the specimen with a higher acetylation degree presents a greater resistance against fracture. This study describes the role of the functional group, acetyl groups, in crystalline chitin. Such information could provide preliminary understanding of nanomaterials when similar functional groups are encountered. PMID:26742033

  4. Effect of Acetyl Group on Mechanical Properties of Chitin/Chitosan Nanocrystal: A Molecular Dynamics Study.

    PubMed

    Cui, Junhe; Yu, Zechuan; Lau, Denvid

    2016-01-05

    Chitin fiber is the load-bearing component in natural chitin-based materials. In these materials, chitin is always partially deacetylated to different levels, leading to diverse material properties. In order to understand how the acetyl group enhances the fracture resistance capability of chitin fiber, we constructed atomistic models of chitin with varied acetylation degree and analyzed the hydrogen bonding pattern, fracture, and stress-strain behavior of these models. We notice that the acetyl group can contribute to the formation of hydrogen bonds that can stabilize the crystalline structure. In addition, it is found that the specimen with a higher acetylation degree presents a greater resistance against fracture. This study describes the role of the functional group, acetyl groups, in crystalline chitin. Such information could provide preliminary understanding of nanomaterials when similar functional groups are encountered.

  5. Acetylation of RNA Polymerase II Regulates Growth-Factor-Induced Gene Transcription in Mammalian Cells

    PubMed Central

    Schröder, Sebastian; Herker, Eva; Itzen, Friederike; He, Daniel; Thomas, Sean; Gilchrist, Daniel A.; Kaehlcke, Katrin; Cho, Sungyoo; Pollard, Katherine S.; Capra, John A.; Schnölzer, Martina; Cole, Philip A.; Geyer, Matthias; Bruneau, Benoit G.; Adelman, Karen; Ott, Melanie

    2014-01-01

    SUMMARY Lysine acetylation regulates transcription by targeting histones and nonhistone proteins. Here we report that the central regulator of transcription, RNA polymerase II, is subject to acetylation in mammalian cells. Acetylation occurs at eight lysines within the C-terminal domain (CTD) of the largest polymerase subunit and is mediated by p300/KAT3B. CTD acetylation is specifically enriched downstream of the transcription start sites of polymerase-occupied genes genome-wide, indicating a role in early stages of transcription initiation or elongation. Mutation of lysines or p300 inhibitor treatment causes the loss of epidermal growth-factor-induced expression of c-Fos and Egr2, immediate-early genes with promoter-proximally paused polymerases, but does not affect expression or polymerase occupancy at housekeeping genes. Our studies identify acetylation as a new modification of the mammalian RNA polymerase II required for the induction of growth factor response genes. PMID:24207025

  6. Posttranslational modifications of alpha-tubulin: acetylated and detyrosinated forms in axons of rat cerebellum

    PubMed Central

    1987-01-01

    The distribution of acetylated alpha-tubulin in rat cerebellum was examined and compared with that of total alpha-tubulin and tyrosinated alpha-tubulin. From immunoperoxidase-stained vibratome sections of rat cerebellum it was found that acetylated alpha-tubulin, detectable with monoclonal 6-11B-1, was preferentially enriched in axons compared with dendrites. Parallel fiber axons, in particular, were labeled with 6-11B- 1 yet unstained by an antibody recognizing tyrosinated alpha-tubulin, indicating that parallel fibers contain alpha-tubulin that is acetylated and detyrosinated. Axonal microtubules are known to be highly stable and the distribution of acetylated alpha-tubulin in other classes of stable microtubules suggests that acetylation and possibly detyrosination may play a role in the maintenance of stable populations of microtubules. PMID:3294857

  7. Acetylome analysis reveals the involvement of lysine acetylation in diverse biological processes in Phytophthora sojae

    PubMed Central

    Li, Delong; Lv, Binna; Tan, Lingling; Yang, Qianqian; Liang, Wenxing

    2016-01-01

    Lysine acetylation is a dynamic and highly conserved post-translational modification that plays an important regulatory role in almost every aspects of cell metabolism in both eukaryotes and prokaryotes. Phytophthora sojae is one of the most important plant pathogens due to its huge economic impact. However, to date, little is known about the functions of lysine acetylation in this Phytopthora. Here, we conducted a lysine acetylome in P. sojae. Overall, 2197 lysine acetylation sites in 1150 proteins were identified. The modified proteins are involved in diverse biological processes and are localized to multiple cellular compartments. Importantly, 7 proteins involved in the pathogenicity or the secretion pathway of P. sojae were found to be acetylated. These data provide the first comprehensive view of the acetylome of P. sojae and serve as an important resource for functional analysis of lysine acetylation in plant pathogens. PMID:27412925

  8. Alcoholism: A Developmental Disorder.

    ERIC Educational Resources Information Center

    Tarter, Ralph E.; Vanyukov, Michael

    1994-01-01

    Alcoholism etiology is discussed from developmental behavior genetic perspective. Temperament features that appear to be associated with heightened risk for alcoholism are examined. Their interactions with the environment during course of development are considered within epigenetic framework and, as discussed, have ramifications for improving…

  9. Molecular basis of alcoholism.

    PubMed

    Most, Dana; Ferguson, Laura; Harris, R Adron

    2014-01-01

    Acute alcohol intoxication causes cellular changes in the brain that last for hours, while chronic alcohol use induces widespread neuroadaptations in the nervous system that can last a lifetime. Chronic alcohol use and the progression into dependence involve the remodeling of synapses caused by changes in gene expression produced by alcohol. The progression of alcohol use, abuse, and dependence can be divided into stages, which include intoxication, withdrawal, and craving. Each stage is associated with specific changes in gene expression, cellular function, brain circuits, and ultimately behavior. What are the molecular mechanisms underlying the transition from recreational use (acute) to dependence (chronic)? What cellular adaptations result in drug memory retention, leading to the persistence of addictive behaviors, even after prolonged drug abstinence? Research into the neurobiology of alcoholism aims to answer these questions. This chapter will describe the molecular adaptations caused by alcohol use and dependence, and will outline key neurochemical participants in alcoholism at the molecular level, which are also potential targets for therapy.

  10. Molecular basis of alcoholism.

    PubMed

    Most, Dana; Ferguson, Laura; Harris, R Adron

    2014-01-01

    Acute alcohol intoxication causes cellular changes in the brain that last for hours, while chronic alcohol use induces widespread neuroadaptations in the nervous system that can last a lifetime. Chronic alcohol use and the progression into dependence involve the remodeling of synapses caused by changes in gene expression produced by alcohol. The progression of alcohol use, abuse, and dependence can be divided into stages, which include intoxication, withdrawal, and craving. Each stage is associated with specific changes in gene expression, cellular function, brain circuits, and ultimately behavior. What are the molecular mechanisms underlying the transition from recreational use (acute) to dependence (chronic)? What cellular adaptations result in drug memory retention, leading to the persistence of addictive behaviors, even after prolonged drug abstinence? Research into the neurobiology of alcoholism aims to answer these questions. This chapter will describe the molecular adaptations caused by alcohol use and dependence, and will outline key neurochemical participants in alcoholism at the molecular level, which are also potential targets for therapy. PMID:25307570

  11. Fetal Alcohol Spectrum Disorder

    ERIC Educational Resources Information Center

    Caley, Linda M.; Kramer, Charlotte; Robinson, Luther K.

    2005-01-01

    Fetal alcohol spectrum disorder (FASD) is a serious and widespread problem in this country. Positioned within the community with links to children, families, and healthcare systems, school nurses are a critical element in the prevention and treatment of those affected by fetal alcohol spectrum disorder. Although most school nurses are familiar…

  12. Cardiovascular effects of alcohol.

    PubMed Central

    Davidson, D M

    1989-01-01

    The effects of alcohol on the heart include modification of the risk of coronary artery disease, the development of alcoholic cardiomyopathy, exacerbation of conduction disorders, atrial and ventricular dysrhythmias, and an increased risk of hypertension, hemorrhagic stroke, infectious endocarditis, and fetal heart abnormalities. PMID:2686174

  13. Fetal Alcohol Syndrome.

    ERIC Educational Resources Information Center

    Zerrer, Peggy

    The paper reviews Fetal Alcohol Syndrome (FAS), a series of effects seen in children whose mothers drink alcohol to excess during pregnancy. The identification of FAS and its recognition as a major health problem in need of prevention are traced. Characteristics of children with FAS are described and resultant growth retardation, abnormal physical…

  14. The Fetal Alcohol Syndrome.

    ERIC Educational Resources Information Center

    Umbreit, John; Ostrow, Lisa S.

    1980-01-01

    Fetal alcohol syndrome is a pattern of altered growth and morphogenesis found in about half the offspring of severely and chronically alcoholic women who continue drinking throughout their pregnancy. Of children studied, mild to moderate mental retardation was the most common disorder, occurring in 44 percent of the cases. (PHR)

  15. Alcohol and You.

    ERIC Educational Resources Information Center

    Hargraves, Ruth; And Others

    Prepared in response to a request from members of the United Methodist Church, this guide can be used with high school students generally, if the theological orientation is recognized. The guide provides opportunities, in four lesson outlines, to share experiences concerning alcohol use, to present information regarding the effect of alcohol on…

  16. Acetylated Hyaluronic Acid: Enhanced Bioavailability and Biological Studies

    PubMed Central

    Saturnino, Carmela; Sinicropi, Maria Stefania; Puoci, Francesco

    2014-01-01

    Hyaluronic acid (HA), a macropolysaccharidic component of the extracellular matrix, is common to most species and it is found in many sites of the human body, including skin and soft tissue. Not only does HA play a variety of roles in physiologic and in pathologic events, but it also has been extensively employed in cosmetic and skin-care products as drug delivery agent or for several biomedical applications. The most important limitations of HA are due to its short half-life and quick degradation in vivo and its consequently poor bioavailability. In the aim to overcome these difficulties, HA is generally subjected to several chemical changes. In this paper we obtained an acetylated form of HA with increased bioavailability with respect to the HA free form. Furthermore, an improved radical scavenging and anti-inflammatory activity has been evidenced, respectively, on ABTS radical cation and murine monocyte/macrophage cell lines (J774.A1). PMID:25114930

  17. Writers and Readers of Histone Acetylation: Structure, Mechanism, and Inhibition

    PubMed Central

    Marmorstein, Ronen; Zhou, Ming-Ming

    2014-01-01

    Histone acetylation marks are written by histone acetyltransferases (HATs) and read by bromodomains (BrDs), and less commonly by other protein modules. These proteins regulate many transcription-mediated biological processes, and their aberrant activities are correlated with several human diseases. Consequently, small molecule HAT and BrD inhibitors with therapeutic potential have been developed. Structural and biochemical studies of HATs and BrDs have revealed that HATs fall into distinct subfamilies containing a structurally related core for cofactor binding, but divergent flanking regions for substrate-specific binding, catalysis, and autoregulation. BrDs adopt a conserved left-handed four-helix bundle to recognize acetyllysine; divergent loop residues contribute to substrate-specific acetyllysine recognition. PMID:24984779

  18. Acetylation of barnyardgrass starch with acetic anhydride under iodine catalysis.

    PubMed

    Bartz, Josiane; Goebel, Jorge Tiago; Giovanaz, Marcos Antônio; Zavareze, Elessandra da Rosa; Schirmer, Manoel Artigas; Dias, Alvaro Renato Guerra

    2015-07-01

    Barnyardgrass (Echinochloa crus-galli) is an invasive plant that is difficult to control and is found in abundance as part of the waste of the paddy industry. In this study, barnyardgrass starch was extracted and studied to obtain a novel starch with potential food and non-food applications. We report some of the physicochemical, functional and morphological properties as well as the effect of modifying this starch with acetic anhydride by catalysis with 1, 5 or 10mM of iodine. The extent of the introduction of acetyl groups increased with increasing iodine levels as catalyst. The shape of the granules remained unaltered, but there were low levels of surface corrosion and the overall relative crystallinity decreased. The pasting temperature, enthalpy and other gelatinisation temperatures were reduced by the modification. There was an increase in the viscosity of the pastes, except for the peak viscosity, which was strongly reduced in 10mM iodine.

  19. Effects of 2(3)-tert-butyl-4-hydroxyanisole pretreatment on cefpiramide binding to mouse glutathione S-transferases.

    PubMed

    Nishiya, H; Haga, T; Nozue, N; Komatsu, T; Baba, M; Ueda, Y; Ono, Y; Kunii, O

    1989-01-01

    Binding of cefpiramide (CPM) and other beta-lactam antimicrobial agents to 2(3)-tert-butyl-4-hydroxyanisole (BHA)-induced liver glutathione (GSH) S-transferases (EC 2.5.1.18) from CD-1 mice was studied. A marked induction of hepatic GSH S-transferase from mice fed BHA was observed. Gel chromatography of liver cytosol from mice fed BHA showed an increased binding of CPM, cefotetan and cefazolin to BHA-induced GSH S-transferases. The extent of their binding to GSH S-transferase seemed to be correlated with the extent of their excretion into the bile. Binding of CPM to the GSH S-transferase fraction was inhibited by both indocyanine green, which is known to bind liver GSH S-transferases intensively, and by cefoperazon, which is mainly excreted into the bile. This study suggests that GSH S-transferases are the main binding proteins of CPM in the liver cytosol fraction and play an important role as carrier proteins of CPM and some antimicrobial agents in mouse liver.

  20. [Alcohol and working].

    PubMed

    Mangili, A

    2004-01-01

    Due to its negative impact on both health and productivity, alcohol misuse is a serious concern in the workplace. Some occupations (e.g. employees of the catering and hotel trade, seamen, sales representatives, brewers and distillers, journalists, physicians, lawyers) are associated with a high rate of alcohol abuse. Alcohol intake can modify worker's behaviour (impaired judgement and vigilance, dulled reflexes) causing reduced performance, mistakes during operating procedures, accidents and injuries. Moreover it can affect the toxicokinetic and toxicodinamic properties of several substances in the workplace, inducing a more complex evaluation of exposure assessment and diagnostic procedures of occupational diseases. The occupational physician, during health surveillance program, can face several alcohol related issues. These entail diagnostic evaluation of alcoholism, job fitness evaluation, in heavy drinkers, advise of rehabilitation and health promotion program.