WorldWideScience

Sample records for acid amide hydrolase

  1. Method for enhancing amidohydrolase activity of fatty acid amide hydrolase

    Energy Technology Data Exchange (ETDEWEB)

    John, George; Nagarajan, Subbiah; Chapman, Kent; Faure, Lionel; Koulen, Peter

    2016-10-25

    A method for enhancing amidohydrolase activity of Fatty Acid Amide Hydrolase (FAAH) is disclosed. The method comprising administering a phenoxyacylethanolamide that causes the enhanced activity. The enhanced activity can have numerous effects on biological organisms including, for example, enhancing the growth of certain seedlings. The subject matter disclosed herein relates to enhancers of amidohydrolase activity.

  2. Luciferin Amides Enable in Vivo Bioluminescence Detection of Endogenous Fatty Acid Amide Hydrolase Activity.

    Science.gov (United States)

    Mofford, David M; Adams, Spencer T; Reddy, G S Kiran Kumar; Reddy, Gadarla Randheer; Miller, Stephen C

    2015-07-15

    Firefly luciferase is homologous to fatty acyl-CoA synthetases. We hypothesized that the firefly luciferase substrate d-luciferin and its analogs are fatty acid mimics that are ideally suited to probe the chemistry of enzymes that release fatty acid products. Here, we synthesized luciferin amides and found that these molecules are hydrolyzed to substrates for firefly luciferase by the enzyme fatty acid amide hydrolase (FAAH). In the presence of luciferase, these molecules enable highly sensitive and selective bioluminescent detection of FAAH activity in vitro, in live cells, and in vivo. The potency and tissue distribution of FAAH inhibitors can be imaged in live mice, and luciferin amides serve as exemplary reagents for greatly improved bioluminescence imaging in FAAH-expressing tissues such as the brain.

  3. Fatty acid amide hydrolase inhibition by neurotoxic organophosphorus pesticides.

    Science.gov (United States)

    Quistad, G B; Sparks, S E; Casida, J E

    2001-05-15

    Organophosphorus (OP) compound-induced inhibition of acetylcholinesterase (AChE) and neuropathy target esterase explains the rapid onset and delayed neurotoxic effects, respectively, for OP insecticides and related compounds but apparently not a third or intermediate syndrome with delayed onset and reduced limb mobility. This investigation tests the hypothesis that fatty acid amide hydrolase (FAAH), a modulator of endogenous signaling compounds affecting sleep (oleamide) and analgesia (anandamide), is a sensitive target for OP pesticides with possible secondary neurotoxicity. Chlorpyrifos oxon inhibits 50% of the FAAH activity (IC50 at 15 min, 25 degrees C, pH 9.0) in vitro at 40--56 nM for mouse brain and liver, whereas methyl arachidonyl phosphonofluoridate, ethyl octylphosphonofluoridate (EOPF), oleyl-4H-1,3,2-benzodioxaphosphorin 2-oxide (oleyl-BDPO), and dodecyl-BDPO give IC50s of 0.08--1.1 nM. These BDPOs and EOPF inhibit mouse brain FAAH in vitro with > or =200-fold higher potency than for AChE. Five OP pesticides inhibit 50% of the brain FAAH activity (ED50) at diazinon, and methamidophos occurs near acutely toxic levels, profenofos and tribufos are effective at asymptomatic doses. Two BDPOs (dodecyl and phenyl) and EOPF are potent inhibitors of FAAH in vivo (ED50 0.5--6 mg/kg). FAAH inhibition of > or =76% in brain depresses movement of mice administered anandamide at 30 mg/kg ip, often leading to limb recumbency. Thus, OP pesticides and related inhibitors of FAAH potentiate the cannabinoid activity of anandamide in mice. More generally, OP compound-induced FAAH inhibition and the associated anandamide accumulation may lead to reduced limb mobility as a secondary neurotoxic effect.

  4. Pain and beyond: fatty acid amides and fatty acid amide hydrolase inhibitors in cardiovascular and metabolic diseases.

    Science.gov (United States)

    Pillarisetti, Sivaram; Alexander, Christopher W; Khanna, Ish

    2009-12-01

    Fatty acid amide hydrolase (FAAH) is responsible for the hydrolysis of several important endogenous fatty acid amides (FAAs), including anandamide, oleoylethanolamide and palmitoylethanolamide. Because specific FAAs interact with cannabinoid and vanilloid receptors, they are often referred to as 'endocannabinoids' or 'endovanilloids'. Initial interest in this area, therefore, has focused on developing FAAH inhibitors to augment the actions of FAAs and reduce pain. However, recent literature has shown that these FAAs - through interactions with unique receptors (extracellular and intracellular) - can induce a diverse array of effects that include appetite suppression, modulation of lipid and glucose metabolism, vasodilation, cardiac function and inflammation. This review gives an overview of FAAs and diverse FAAH inhibitors and their potential therapeutic utility in pain and non-pain indications.

  5. Discovery of MK-3168: A PET Tracer for Imaging Brain Fatty Acid Amide Hydrolase.

    Science.gov (United States)

    Liu, Ping; Hamill, Terence G; Chioda, Marc; Chobanian, Harry; Fung, Selena; Guo, Yan; Chang, Linda; Bakshi, Raman; Hong, Qingmei; Dellureficio, James; Lin, Linus S; Abbadie, Catherine; Alexander, Jessica; Jin, Hong; Mandala, Suzanne; Shiao, Lin-Lin; Li, Wenping; Sanabria, Sandra; Williams, David; Zeng, Zhizhen; Hajdu, Richard; Jochnowitz, Nina; Rosenbach, Mark; Karanam, Bindhu; Madeira, Maria; Salituro, Gino; Powell, Joyce; Xu, Ling; Terebetski, Jenna L; Leone, Joseph F; Miller, Patricia; Cook, Jacquelynn; Holahan, Marie; Joshi, Aniket; O'Malley, Stacey; Purcell, Mona; Posavec, Diane; Chen, Tsing-Bau; Riffel, Kerry; Williams, Mangay; Hargreaves, Richard; Sullivan, Kathleen A; Nargund, Ravi P; DeVita, Robert J

    2013-06-13

    We report herein the discovery of a fatty acid amide hydrolase (FAAH) positron emission tomography (PET) tracer. Starting from a pyrazole lead, medicinal chemistry efforts directed toward reducing lipophilicity led to the synthesis of a series of imidazole analogues. Compound 6 was chosen for further profiling due to its appropriate physical chemical properties and excellent FAAH inhibition potency across species. [(11)C]-6 (MK-3168) exhibited good brain uptake and FAAH-specific signal in rhesus monkeys and is a suitable PET tracer for imaging FAAH in the brain.

  6. Pyrazole phenylcyclohexylcarbamates as inhibitors of human fatty acid amide hydrolases (FAAH).

    Science.gov (United States)

    Aghazadeh Tabrizi, Mojgan; Baraldi, Pier Giovanni; Ruggiero, Emanuela; Saponaro, Giulia; Baraldi, Stefania; Romagnoli, Romeo; Martinelli, Adriano; Tuccinardi, Tiziano

    2015-06-05

    Fatty acid amide hydrolase (FAAH) inhibitors have gained attention as potential therapeutic targets in the management of neuropathic pain. Here, we report a series of pyrazole phenylcyclohexylcarbamate derivatives standing on the known carbamoyl FAAH inhibitor URB597. Structural modifications led to the recognition of compound 22 that inhibited human recombinant FAAH (hrFAAH) in the low nanomolar range (IC50 = 11 nM). The most active compounds of this series showed significant selectivity toward monoacylglycerol lipase (MAGL) enzyme. In addition, molecular modeling and reversibility behavior of the new class of FAAH inhibitors are presented in this article.

  7. Fatty Acid Amide Hydrolase (FAAH) Inhibition Enhances Memory Acquisition through Activation of PPAR-alpha Nuclear Receptors

    Science.gov (United States)

    Mazzola, Carmen; Medalie, Julie; Scherma, Maria; Panlilio, Leigh V.; Solinas, Marcello; Tanda, Gianluigi; Drago, Filippo; Cadet, Jean Lud; Goldberg, Steven R.; Yasar, Sevil

    2009-01-01

    Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of anandamide (a cannabinoid CB[subscript 1]-receptor ligand) and oleoylethanolamide and palmitoylethanolamide (OEA and PEA, ligands for alpha-type peroxisome proliferator-activated nuclear receptors, PPAR-alpha) when and where they are naturally released in the brain.…

  8. Overexpression of fatty acid amide hydrolase induces early flowering in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Neal D. Teaster

    2012-02-01

    Full Text Available N-Acylethanolamines (NAEs are bioactive lipids derived from the hydrolysis of the membrane phospholipid N-acylphosphatidylethanolamine (NAPE. In animal systems this reaction is part of the endocannabinoid signaling pathway, which regulates a variety of physiological processes. The signaling function of NAE is terminated by fatty acid amide hydrolase (FAAH, which hydrolyzes NAE to ethanolamine and free fatty acid. Our previous work in Arabidopsis thaliana showed that overexpression of AtFAAH (At5g64440 lowered endogenous levels of NAEs in seeds, consistent with its role in NAE signal termination. Reduced NAE levels were accompanied by an accelerated growth phenotype, increased sensitivity to abscisic acid (ABA, enhanced susceptibility to bacterial pathogens, and early flowering. Here we investigated the nature of the early flowering phenotype of AtFAAH overexpression. AtFAAH overexpressors flowered several days earlier than wild type and AtFAAH knockouts under both non-inductive short day (SD and inductive long day (LD conditions. Microarray analysis revealed that the FLOWERING LOCUS T (FT gene, which plays a major role in regulating flowering time, and one target MADS box transcription factor, SEPATALLA3 (SEP3, were elevated in AtFAAH overexpressors. Furthermore, AtFAAH overexpressors, with the early flowering phenotype had lower endogenous NAE levels in leaves compared to wild type prior to flowering. Exogenous application of NAE 12:0, which was reduced by up to 30% in AtFAAH overexpressors, delayed the onset of flowering in wild type plants. We conclude that the early flowering phenotype of AtFAAH overexpressors is, in part, explained by elevated FT gene expression resulting from the enhanced NAE hydrolase activity of AtFAAH, suggesting that NAE metabolism may participate in floral signaling pathways.

  9. Analgesic effects of fatty acid amide hydrolase inhibition in a rat model of neuropathic pain.

    Science.gov (United States)

    Jhaveri, Maulik D; Richardson, Denise; Kendall, David A; Barrett, David A; Chapman, Victoria

    2006-12-20

    Cannabinoid-based medicines have therapeutic potential for the treatment of pain. Augmentation of levels of endocannabinoids with inhibitors of fatty acid amide hydrolase (FAAH) is analgesic in models of acute and inflammatory pain states. The aim of this study was to determine whether local inhibition of FAAH alters nociceptive responses of spinal neurons in the spinal nerve ligation model of neuropathic pain. Electrophysiological studies were performed 14-18 d after spinal nerve ligation or sham surgery, and the effects of the FAAH inhibitor cyclohexylcarbamic acid 3-carbamoyl biphenyl-3-yl ester (URB597) on mechanically evoked responses of spinal neurons and levels of endocannabinoids were determined. Intraplantar URB597 (25 microg in 50 microl) significantly (p < 0.01) attenuated mechanically evoked responses of spinal neurons in sham-operated rats. Effects of URB597 were blocked by the cannabinoid 1 receptor (CB1) antagonist AM251 [N-1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-1-piperidinyl-1H-pyrazole-3-carboxamide] (30 microg in 50 microl) and the opioid receptor antagonist naloxone. URB597 treatment increased levels of anandamide, 2-arachidonyl glycerol, and oleoyl ethanolamide in the ipsilateral hindpaw of sham-operated rats. Intraplantar URB597 (25 microg in 50 microl) did not, however, alter mechanically evoked responses of spinal neurons in spinal nerve ligated (SNL) rats or hindpaw levels of endocannabinoids. Intraplantar injection of a higher dose of URB597 (100 microg in 50 microl) significantly (p < 0.05) attenuated evoked responses of spinal neurons in SNL rats but did not alter hindpaw levels of endocannabinoids. Spinal administration of URB597 attenuated evoked responses of spinal neurons and elevated levels of endocannabinoids in sham-operated and SNL rats. These data suggest that peripheral FAAH activity may be altered or that alternative pathways of metabolism have greater importance in SNL rats.

  10. Oxygenated metabolites of anandamide and 2-arachidonoylglycerol : conformational analysis and interaction with cannabinoid receptors, membrane transporter, and fatty acid amide hydrolase

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Stelt, M. van der; Kuik, J.A. van; Zadelhoff, G. van; Leeflang, B.R.; Veldink, G.A.; Finazzi Agrò, A.; Maccarrone, M.

    2002-01-01

    This study was aimed at finding structural requirements for the interaction of the acyl chain of endocannabinoids with cannabinoid receptors, membrane transporter protein, and fatty acid amide hydrolase (FAAH). To this end, the flexibility of the acyl chain was restricted by introduction of an 1-hyd

  11. Fatty acid amide hydrolase as a potential therapeutic target for the treatment of pain and CNS disorders

    Science.gov (United States)

    Ahn, Kay; Johnson, Douglas S.; Cravatt, Benjamin F.

    2009-01-01

    Background Fatty acid amide hydrolase (FAAH) is an integral membrane enzyme that hydrolyzes the endocannabinoid anandamide and related amidated signaling lipids. Genetic or pharmacological inactivation of FAAH produces analgesic, anti-inflammatory, anxiolytic, and antidepressant phenotypes without showing the undesirable side effects of direct cannabinoid receptor agonists, indicating that FAAH may be a promising therapeutic target. Objectives This review highlights advances in the development of FAAH inhibitors of different mechanistic classes and their in vivo efficacy. Also highlighted are advances in technology for the in vitro and in vivo selectivity assessment of FAAH inhibitors employing activity-based protein profiling (ABPP) and click chemistry-ABPP, respectively. Recent reports on structure-based drug design for human FAAH generated by protein engineering using interspecies active site conversion are also discussed. Methods: The literature searches of Medline and SciFinder databases were used. Conclusions There has been tremendous progress in our understanding in FAAH and development of FAAH inhibitors with in vivo efficacy, selectivity, and drug like pharmacokinetic properties. PMID:20544003

  12. Intracellular Self-Assembly of Cyclic d-Luciferin Nanoparticles for Persistent Bioluminescence Imaging of Fatty Acid Amide Hydrolase.

    Science.gov (United States)

    Yuan, Yue; Wang, Fuqiang; Tang, Wei; Ding, Zhanling; Wang, Lin; Liang, Lili; Zheng, Zhen; Zhang, Huafeng; Liang, Gaolin

    2016-07-26

    Fatty acid amide hydrolase (FAAH) overexpression induces several disorder symptoms in nerve systems, and therefore long-term tracing of FAAH activity in vivo is of high importance but remains challenging. Current bioluminescence (BL) methods are limited in detecting FAAH activity within 5 h. Herein, by rational design of a latent BL probe (d-Cys-Lys-CBT)2 (1), we developed a "smart" method of intracellular reduction-controlled self-assembly and FAAH-directed disassembly of its cyclic d-luciferin-based nanoparticles (i.e., 1-NPs) for persistent BL imaging of FAAH activity in vitro, in cells, and in vivo. Using aminoluciferin methyl amide (AMA), Lys-amino-d-luciferin (Lys-Luc), and amino-d-luciferin (NH2-Luc) as control BL probes, we validated that the persistent BL of 1 from luciferase-expressing cells or tumors was controlled by the activity of intracellular FAAH. With the property of long-term tracing of FAAH activity in vivo of 1, we envision that our BL precursor 1 could probably be applied for in vivo screening of FAAH inhibitors and the diagnosis of their related diseases (or disorders) in the future.

  13. Lipopolysaccharide-induced pulmonary inflammation is not accompanied by a release of anandamide into the lavage fluid or a down-regulation of the activity of fatty acid amide hydrolase

    DEFF Research Database (Denmark)

    Holt, S.; J. Fowler, C.; Rocksén, D.;

    2004-01-01

    The effect of lipopolysaccharide inhalation upon lung anandamide levels, anandamide synthetic enzymes and fatty acid amide hydrolase has been investigated. Lipopolysaccharide exposure produced a dramatic extravasation of neutrophils and release of tumour necrosis factor a into the bronchoalveolar......-acyltransferase and N-acylphosphatidylethanolamine phospholipase D and the activity of fatty acid amide hydrolase in lung membrane fractions did not change significantly following the exposure to lipopolysaccharide. The non-selective fatty acid amide hydrolase inhibitor phenylmethylsulfonyl fluoride was a less potent...... inhibitor of lung fatty acid amide hydrolase than expected from the literature, and a dose of 30 mg/kg i.p. of this compound, which produced a complete inhibition of brain anandamide metabolism, only partially inhibited the lung metabolic activity. © 2004 Elsevier Inc. All rights reserved....

  14. A new perspective on cannabinoid signalling: complementary localization of fatty acid amide hydrolase and the CB1 receptor in rat brain.

    OpenAIRE

    1998-01-01

    CB1-type cannabinoid receptors in the brain mediate effects of the drug cannabis. Anandamide and sn-2 arachidonylglycerol (2-AG) are putative endogenous ligands for CB1 receptors, but it is not known which cells in the brain produce these molecules. Recently, an enzyme which catalyses hydrolysis of anandamide and 2-AG, known as fatty acid amide hydrolase (FAAH), was identified in mammals. Here we have analysed the distribution of FAAH in rat brain and compared its cellular localization with C...

  15. Parabens inhibit fatty acid amide hydrolase: A potential role in paraben-enhanced 3T3-L1 adipocyte differentiation.

    Science.gov (United States)

    Kodani, Sean D; Overby, Haley B; Morisseau, Christophe; Chen, Jiangang; Zhao, Ling; Hammock, Bruce D

    2016-11-16

    Parabens are a class of small molecules that are regularly used as preservatives in a variety of personal care products. Several parabens, including butylparaben and benzylparaben, have been found to interfere with endocrine signaling and to stimulate adipocyte differentiation. We hypothesized these biological effects could be due to interference with the endocannabinoid system and identified fatty acid amide hydrolase (FAAH) as the direct molecular target of parabens. FAAH inhibition by parabens yields mixed-type and time-independent kinetics. Additionally, structure activity relationships indicate FAAH inhibition is selective for the paraben class of compounds and the more hydrophobic parabens have higher potency. Parabens enhanced 3T3-L1 adipocyte differentiation in a dose dependent fashion, different from two other FAAH inhibitors URB597 and PF622. Moreover, parabens, URB597 and PF622 all failed to enhance AEA-induced differentiation. Furthermore, rimonabant, a cannabinoid receptor 1 (CB1)-selective antagonist, did not attenuate paraben-induced adipocyte differentiation. Thus, adipogenesis mediated by parabens likely occurs through modulation of endocannabinoids, but cell differentiation is independent of direct activation of CB1 by endocannabinoids.

  16. Dysfunction in fatty acid amide hydrolase is associated with depressive-like behavior in Wistar Kyoto rats.

    Directory of Open Access Journals (Sweden)

    K Yaragudri Vinod

    Full Text Available BACKGROUND: While the etiology of depression is not clearly understood at the present time, this mental disorder is thought be a complex and multifactorial trait with important genetic and environmental contributing factors. METHODOLOGY/PRINCIPAL FINDINGS: The role of the endocannabinoid (eCB system in depressive behavior was examined in Wistar Kyoto (WKY rat strain, a genetic model of depression. Our findings revealed selective abnormalities in the eCB system in the brains of WKY rats compared to Wistar (WIS rats. Immunoblot analysis indicated significantly higher levels of fatty acid amide hydrolase (FAAH in frontal cortex and hippocampus of WKY rats with no alteration in the level of N-arachidonyl phosphatidyl ethanolamine specific phospholipase-D (NAPE-PLD. Significantly higher levels of CB1 receptor-mediated G-protein coupling and lower levels of anandamide (AEA were found in frontal cortex and hippocampus of WKY rats. While the levels of brain derived neurotropic factor (BDNF were significantly lower in frontal cortex and hippocampus of WKY rats compared to WIS rats, pharmacological inhibition of FAAH elevated BDNF levels in WKY rats. Inhibition of FAAH enzyme also significantly increased sucrose consumption and decreased immobility in the forced swim test in WKY rats. CONCLUSIONS/SIGNIFICANCE: These findings suggest a critical role for the eCB system and BDNF in the genetic predisposition to depressive-like behavior in WKY rats and point to the potential therapeutic utility of eCB enhancing agents in depressive disorder.

  17. Effect of social isolation on CB1 and D2 receptor and fatty acid amide hydrolase expression in rats.

    Science.gov (United States)

    Malone, D T; Kearn, C S; Chongue, L; Mackie, K; Taylor, D A

    2008-03-03

    Rearing rats in isolation has been shown to produce behavioral and neurochemical alterations similar to those observed in psychoses such as schizophrenia. Also, a dysregulation in both the endocannabinoid and dopaminergic systems has been implicated in schizophrenia. The aim of this study was to determine if there are differences in CB1 receptor and fatty acid amide hydrolase (FAAH) protein expression, as well as D2 dopamine receptor expression in different brain regions in rats reared in different environmental conditions. Twenty-one-day-old male Sprague-Dawley rats were either reared in individual cages (isolated rats) or in group cages of six per cage (group-housed rats) for 8 weeks. Quantitative fluorescence immunohistochemistry was performed on brain slices using antibodies specific to the CB1 or D2 receptor, or the enzyme FAAH. Raising rats in isolation led to a significant decrease in CB1 receptor expression in the caudate putamen and the amygdala, a significant increase in FAAH expression in the caudate putamen and the nucleus accumbens core and shell, and no significant change in D2 receptor expression in any region studied. These results indicate that the endocannabinoid system is altered in an animal model of aspects of psychosis. This implies that rearing rats under different housing conditions may provide new insight into the role of the endocannabinoid system in the development of psychoses.

  18. Cardioprotective effects of fatty acid amide hydrolase inhibitor URB694, in a rodent model of trait anxiety.

    Science.gov (United States)

    Carnevali, Luca; Vacondio, Federica; Rossi, Stefano; Macchi, Emilio; Spadoni, Gilberto; Bedini, Annalida; Neumann, Inga D; Rivara, Silvia; Mor, Marco; Sgoifo, Andrea

    2015-12-14

    In humans, chronic anxiety represents an independent risk factor for cardiac arrhythmias and sudden death. Here we evaluate in male Wistar rats bred for high (HAB) and low (LAB) anxiety-related behavior, as well as non-selected (NAB) animals, the relationship between trait anxiety and cardiac electrical instability and investigate whether pharmacological augmentation of endocannabinoid anandamide-mediated signaling exerts anxiolytic-like and cardioprotective effects. HAB rats displayed (i) a higher incidence of ventricular tachyarrhythmias induced by isoproterenol, and (ii) a larger spatial dispersion of ventricular refractoriness assessed by means of an epicardial mapping protocol. In HAB rats, acute pharmacological inhibition of the anandamide-degrading enzyme, fatty acid amide hydrolase (FAAH), with URB694 (0.3 mg/kg), (i) decreased anxiety-like behavior in the elevated plus maze, (ii) increased anandamide levels in the heart, (iii) reduced isoproterenol-induced occurrence of ventricular tachyarrhythmias, and (iv) corrected alterations of ventricular refractoriness. The anti-arrhythmic effect of URB694 was prevented by pharmacological blockade of the cannabinoid type 1 (CB1), but not of the CB2, receptor. These findings suggest that URB694 exerts anxiolytic-like and cardioprotective effects in HAB rats, the latter via anandamide-mediated activation of CB1 receptors. Thus, pharmacological inhibition of FAAH might be a viable pharmacological strategy for the treatment of anxiety-related cardiac dysfunction.

  19. Fatty acid amide hydrolase-dependent generation of antinociceptive drug metabolites acting on TRPV1 in the brain.

    Directory of Open Access Journals (Sweden)

    David A Barrière

    Full Text Available The discovery that paracetamol is metabolized to the potent TRPV1 activator N-(4-hydroxyphenyl-5Z,8Z,11Z,14Z-eicosatetraenamide (AM404 and that this metabolite contributes to paracetamol's antinociceptive effect in rodents via activation of TRPV1 in the central nervous system (CNS has provided a potential strategy for developing novel analgesics. Here we validated this strategy by examining the metabolism and antinociceptive activity of the de-acetylated paracetamol metabolite 4-aminophenol and 4-hydroxy-3-methoxybenzylamine (HMBA, both of which may undergo a fatty acid amide hydrolase (FAAH-dependent biotransformation to potent TRPV1 activators in the brain. Systemic administration of 4-aminophenol and HMBA led to a dose-dependent formation of AM404 plus N-(4-hydroxyphenyl-9Z-octadecenamide (HPODA and arvanil plus olvanil in the mouse brain, respectively. The order of potency of these lipid metabolites as TRPV1 activators was arvanil = olvanil>>AM404> HPODA. Both 4-aminophenol and HMBA displayed antinociceptive activity in various rodent pain tests. The formation of AM404, arvanil and olvanil, but not HPODA, and the antinociceptive effects of 4-aminophenol and HMBA were substantially reduced or disappeared in FAAH null mice. The activity of 4-aminophenol in the mouse formalin, von Frey and tail immersion tests was also lost in TRPV1 null mice. Intracerebroventricular injection of the TRPV1 blocker capsazepine eliminated the antinociceptive effects of 4-aminophenol and HMBA in the mouse formalin test. In the rat, pharmacological inhibition of FAAH, TRPV1, cannabinoid CB1 receptors and spinal 5-HT3 or 5-HT1A receptors, and chemical deletion of bulbospinal serotonergic pathways prevented the antinociceptive action of 4-aminophenol. Thus, the pharmacological profile of 4-aminophenol was identical to that previously reported for paracetamol, supporting our suggestion that this drug metabolite contributes to paracetamol's analgesic activity via

  20. Mutation screen and association studies for the fatty acid amide hydrolase (FAAH gene and early onset and adult obesity

    Directory of Open Access Journals (Sweden)

    Rief Winfried

    2010-01-01

    Full Text Available Abstract Background The orexigenic effects of cannabinoids are limited by activation of the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH. The aim of this study was to analyse whether FAAH alleles are associated with early and late onset obesity. Methods We initially assessed association of five single nucleotide polymorphisms (SNPs in FAAH with early onset extreme obesity in up to 521 German obese children and both parents. SNPs with nominal p-values ≤ 0.1 were subsequently analysed in 235 independent German obesity families. SNPs associated with childhood obesity (p-values ≤ 0.05 were further analysed in 8,491 adult individuals of a population-based cohort (KORA for association with adult obesity. One SNP was further analysed in 985 German obese adults and 588 normal and underweight controls. In parallel, we screened the FAAH coding region for novel sequence variants in 92 extremely obese children using single-stranded-conformation-polymorphism-analysis and denaturing HPLC and assessed the implication of the identified new variants for childhood obesity. Results The trio analysis revealed some evidence for an association of three SNPs in FAAH (rs324420 rs324419 and rs873978 with childhood obesity (two-sided p-values between 0.06 and 0.10. Although analyses of these variants in 235 independent obesity families did not result in statistically significant effects (two-sided p-values between 0.14 and 0.75, the combined analysis of all 603 obesity families supported the idea of an association of two SNPs in FAAH (rs324420 and rs2295632 with early onset extreme obesity (p-values between 0.02 and 0.03. No association was, however, found between these variants and adult obesity. The mutation screen revealed four novel variants, which were not associated with early onset obesity (p > 0.05. Conclusions As we observed some evidence for an association of the FAAH variants rs2295632 rs324420 with early onset but not adult obesity

  1. [{sup 11}C]CURB: Evaluation of a novel radiotracer for imaging fatty acid amide hydrolase by positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Alan A., E-mail: alan.wilson@camhpet.c [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Garcia, Armando; Parkes, Jun [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Houle, Sylvain [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Tong, Junchao [Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8 (Canada); Vasdev, Neil [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada)

    2011-02-15

    Introduction: Fatty acid amide hydrolase (FAAH) is the enzyme responsible for metabolising the endogenous cannabinoid, anandamide, and thus represents an important target for molecular imaging. To date, no radiotracer has been shown to be useful for imaging of FAAH using either positron emission tomography (PET) or single photon emission computed tomography (SPECT). We here determine the suitability of a novel carbon-11-labeled inhibitor of FAAH via ex vivo biodistribution studies in rat brain in conjunction with pharmacological challenges. Methods: A potent irreversible inhibitor of FAAH, URB694, radiolabeled with carbon-11 in the carbonyl position ([{sup 11}C]CURB), was administered to male rats via tail-vein injection. Rats were sacrificed at various time points postinjection, and tissue samples were dissected, counted and weighed. Specific binding to FAAH was investigated by pretreatment of animals with URB694 or URB597. For metabolism and mechanism of binding studies, whole brains were excised post-radiotracer injection, homogenised and extracted exhaustively with 80% aq. acetonitrile to determine the time course and fraction of radioactivity that was irreversibly bound to brain parenchyma. Results: Upon intravenous injection into rats, [{sup 11}C]CURB showed high brain uptake [standard uptake value (SUV) of 1.6-2.4 at 5 min] with little washout over time, which is characteristic of irreversible binding. Highest uptake of radioactivity was seen in the cortex, intermediate in the cerebellum and lowest in the hypothalamus, reflecting the reported distribution of FAAH. Brain uptake of radioactivity was decreased in a dose-dependent manner by pretreatment with increasing amounts of URB694, demonstrating that binding was saturable. Pretreatment with the well-characterised FAAH inhibitor, URB597, reduced binding in all brain regions by 70-80%. Homogenised brain extraction experiments demonstrated unequivocally that [{sup 11}C]CURB was irreversibly bound to FAAH

  2. A chemical genetic screen uncovers a small molecule enhancer of the N-acylethanolamine degrading enzyme, fatty acid amide hydrolase, in Arabidopsis

    Science.gov (United States)

    Khan, Bibi Rafeiza; Faure, Lionel; Chapman, Kent D.; Blancaflor, Elison B.

    2017-01-01

    N-Acylethanolamines (NAEs) are a group of fatty acid amides that play signaling roles in diverse physiological processes in eukaryotes. Fatty acid amide hydrolase (FAAH) degrades NAE into ethanolamine and free fatty acid to terminate its signaling function. In animals, chemical inhibitors of FAAH have been used for therapeutic treatment of pain and as tools to probe deeper into biochemical properties of FAAH. In a chemical genetic screen for small molecules that dampened the inhibitory effect of N-lauroylethanolamine (NAE 12:0) on Arabidopsis thaliana seedling growth, we identified 6-(2-methoxyphenyl)-1,3-dimethyl-5-phenyl-1H-pyrrolo[3,4-d]pyrimidine-2,4(3 H,6 H)-dione (or MDPD). MDPD alleviated the growth inhibitory effects of NAE 12:0, in part by enhancing the enzymatic activity of Arabidopsis FAAH (AtFAAH). In vitro, biochemical assays showed that MDPD enhanced the apparent Vmax of AtFAAH but did not alter the affinity of AtFAAH for its NAE substrates. Structural analogs of MDPD did not affect AtFAAH activity or dampen the inhibitory effect of NAE 12:0 on seedling growth indicating that MDPD is a specific synthetic chemical activator of AtFAAH. Collectively, our study demonstrates the feasibility of using an unbiased chemical genetic approach to identify new pharmacological tools for manipulating FAAH- and NAE-mediated physiological processes in plants. PMID:28112243

  3. Fatty acid amide hydrolase (FAAH) inhibitors exert pharmacological effects, but lack antinociceptive efficacy in rats with neuropathic spinal cord injury pain.

    Science.gov (United States)

    Hama, Aldric T; Germano, Peter; Varghese, Matthew S; Cravatt, Benjamin F; Milne, G Todd; Pearson, James P; Sagen, Jacqueline

    2014-01-01

    Amelioration of neuropathic spinal cord injury (SCI) pain is a clinical challenge. Increasing the endocannabinoid anandamide and other fatty acid amides (FAA) by blocking fatty acid amide hydrolase (FAAH) has been shown to be antinociceptive in a number of animal models of chronic pain. However, an antinociceptive effect of blocking FAAH has yet to be demonstrated in a rat model of neuropathic SCI pain. Four weeks following a SCI, rats developed significantly decreased hind paw withdrawal thresholds, indicative of below-level cutaneous hypersensitivity. A group of SCI rats were systemically treated (i.p.) with either the selective FAAH inhibitor URB597 or vehicle twice daily for seven days. A separate group of SCI rats received a single dose (p.o.) of either the selective FAAH inhibitor PF-3845 or vehicle. Following behavioral testing, levels of the FAA N-arachidonoylethanolamide, N-oleoyl ethanolamide and N-palmitoyl ethanolamide were quantified in brain and spinal cord from SCI rats. Four weeks following SCI, FAA levels were markedly reduced in spinal cord tissue. Although systemic treatment with URB597 significantly increased CNS FAA levels, no antinociceptive effect was observed. A significant elevation of CNS FAA levels was also observed following oral PF-3845 treatment, but only a modest antinociceptive effect was observed. Increasing CNS FAA levels alone does not lead to robust amelioration of below-level neuropathic SCI pain. Perhaps utilizing FAAH inhibition in conjunction with other analgesic mechanisms could be an effective analgesic therapy.

  4. Fear-induced suppression of nociceptive behaviour and activation of Akt signalling in the rat periaqueductal grey: role of fatty acid amide hydrolase.

    Science.gov (United States)

    Butler, Ryan K; Ford, Gemma K; Hogan, Michelle; Roche, Michelle; Doyle, Karen M; Kelly, John P; Kendall, David A; Chapman, Victoria; Finn, David P

    2012-01-01

    The endocannabinoid system regulates nociception and aversion and mediates fear-conditioned analgesia (FCA). We investigated the effects of the fatty acid amide hydrolase (FAAH) inhibitor URB597, which inhibits the catabolism of the endocannabinoid anandamide and related N-acylethanolamines, on expression of FCA and fear and pain related behaviour per se in rats. We also examined associated alterations in the expression of the signal transduction molecule phospho-Akt in the periaqueductal grey (PAG) by immunoblotting. FCA was modelled by assessing formalin-evoked nociceptive behaviour in an arena previously paired with footshock. URB597 (0.3 mg/kg, i.p.) enhanced FCA and increased fear-related behaviour in formalin-treated rats. Conditioned fear per se in non-formalin-treated rats was associated with increased expression of phospho-Akt in the PAG. URB597 reduced the expression of fear-related behaviour in the early part of the trial, an effect that was accompanied by attenuation of the fear-induced increase in phospho-Akt expression in the PAG. Intra-plantar injection of formalin also reduced the fear-induced increase in phospho-Akt expression. These data provide evidence for a role of FAAH in FCA, fear responding in the presence or absence of nociceptive tone, and fear-evoked increases in PAG phospho-Akt expression. In addition, the results suggest that fear-evoked activation of Akt signalling in the PAG is abolished in the presence of nociceptive tone.

  5. Multitarget fatty acid amide hydrolase/cyclooxygenase blockade suppresses intestinal inflammation and protects against nonsteroidal anti-inflammatory drug-dependent gastrointestinal damage.

    Science.gov (United States)

    Sasso, Oscar; Migliore, Marco; Habrant, Damien; Armirotti, Andrea; Albani, Clara; Summa, Maria; Moreno-Sanz, Guillermo; Scarpelli, Rita; Piomelli, Daniele

    2015-06-01

    The ability of nonsteroidal anti-inflammatory drugs (NSAIDs) to inhibit cyclooxygenase (Cox)-1 and Cox-2 underlies the therapeutic efficacy of these drugs, as well as their propensity to damage the gastrointestinal (GI) epithelium. This toxic action greatly limits the use of NSAIDs in inflammatory bowel disease (IBD) and other chronic pathologies. Fatty acid amide hydrolase (FAAH) degrades the endocannabinoid anandamide, which attenuates inflammation and promotes GI healing. Here, we describe the first class of systemically active agents that simultaneously inhibit FAAH, Cox-1, and Cox-2 with high potency and selectivity. The class prototype 4: (ARN2508) is potent at inhibiting FAAH, Cox-1, and Cox-2 (median inhibitory concentration: FAAH, 0.031 ± 0.002 µM; Cox-1, 0.012 ± 0.002 µM; and Cox-2, 0.43 ± 0.025 µM) but does not significantly interact with a panel of >100 off targets. After oral administration in mice, ARN2508 engages its intended targets and exerts profound therapeutic effects in models of intestinal inflammation. Unlike NSAIDs, ARN2508 causes no gastric damage and indeed protects the GI from NSAID-induced damage through a mechanism that requires FAAH inhibition. Multitarget FAAH/Cox blockade may provide a transformative approach to IBD and other pathologies in which FAAH and Cox are overactive.

  6. Cannabinoid CB1 and CB2 receptors and fatty acid amide hydrolase are specific markers of plaque cell subtypes in human multiple sclerosis.

    Science.gov (United States)

    Benito, Cristina; Romero, Juan Pablo; Tolón, Rosa María; Clemente, Diego; Docagne, Fabián; Hillard, Cecilia J; Guaza, Camen; Romero, Julián

    2007-02-28

    Increasing evidence supports the idea of a beneficial effect of cannabinoid compounds for the treatment of multiple sclerosis (MS). However, most experimental data come from animal models of MS. We investigated the status of cannabinoid CB1 and CB2 receptors and fatty acid amide hydrolase (FAAH) enzyme in brain tissue samples obtained from MS patients. Areas of demyelination were identified and classified as active, chronic, and inactive plaques. CB1 and CB2 receptors and FAAH densities and cellular sites of expression were examined using immunohistochemistry and immunofluorescence. In MS samples, cannabinoid CB1 receptors were expressed by cortical neurons, oligodendrocytes, and also oligodendrocyte precursor cells, demonstrated using double immunofluorescence with antibodies against the CB1 receptor with antibodies against type 2 microtubule-associated protein, myelin basic protein, and the platelet-derived growth factor receptor-alpha, respectively. CB1 receptors were also present in macrophages and infiltrated T-lymphocytes. Conversely, CB2 receptors were present in T-lymphocytes, astrocytes, and perivascular and reactive microglia (major histocompatibility complex class-II positive) in MS plaques. Specifically, CB2-positive microglial cells were evenly distributed within active plaques but were located in the periphery of chronic active plaques. FAAH expression was restricted to neurons and hypertrophic astrocytes. As seen for other neuroinflammatory conditions, selective glial expression of cannabinoid CB1 and CB2 receptors and FAAH enzyme is induced in MS, thus supporting a role for the endocannabinoid system in the pathogenesis and/or evolution of this disease.

  7. The activity of the endocannabinoid metabolising enzyme fatty acid amide hydrolase in subcutaneous adipocytes correlates with BMI in metabolically healthy humans

    Directory of Open Access Journals (Sweden)

    Alexander Stephen PH

    2011-08-01

    Full Text Available Abstract Background The endocannabinoid system (ECS is a ubiquitously expressed signalling system, with involvement in lipid metabolism and obesity. There are reported changes in obesity of blood concentrations of the endocannabinoids anandamide (AEA and 2-arachidonoylglcyerol (2-AG, and of adipose tissue expression levels of the two key catabolic enzymes of the ECS, fatty acid amide hydrolase (FAAH and monoacylglycerol lipase (MGL. Surprisingly, however, the activities of these enzymes have not been assayed in conditions of increasing adiposity. The aim of the current study was to investigate whether FAAH and MGL activities in human subcutaneous adipocytes are affected by body mass index (BMI, or other markers of adiposity and metabolism. Methods Subcutaneous abdominal mature adipocytes, fasting blood samples and anthropometric measurements were obtained from 28 metabolically healthy subjects representing a range of BMIs. FAAH and MGL activities were assayed in mature adipocytes using radiolabelled substrates. Serum glucose, insulin and adipokines were determined using ELISAs. Results MGL activity showed no relationship with BMI or other adiposity indices, metabolic markers (fasting serum insulin or glucose or serum adipokine levels (adiponectin, leptin or resistin. In contrast, FAAH activity in subcutaneous adipocytes correlated positively with BMI and waist circumference, but not with skinfold thickness, metabolic markers or serum adipokine levels. Conclusions In this study, novel evidence is provided that FAAH activity in subcutaneous mature adipocytes increases with BMI, whereas MGL activity does not. These findings support the hypothesis that some components of the ECS are upregulated with increasing adiposity in humans, and that AEA and 2-AG may be regulated differently.

  8. Structural Fluctuations in Enzyme-Catalyzed Reactions: Determinants of Reactivity in Fatty Acid Amide Hydrolase from Multivariate Statistical Analysis of Quantum Mechanics/Molecular Mechanics Paths.

    Science.gov (United States)

    Lodola, Alessio; Sirirak, Jitnapa; Fey, Natalie; Rivara, Silvia; Mor, Marco; Mulholland, Adrian J

    2010-09-14

    The effects of structural fluctuations, due to protein dynamics, on enzyme activity are at the heart of current debates on enzyme catalysis. There is evidence that fatty acid amide hydrolase (FAAH) is an enzyme for which reaction proceeds via a high-energy, reactive conformation, distinct from the predominant enzyme-substrate complex (Lodola et al. Biophys. J. 2007, 92, L20-22). Identifying the structural causes of differences in reactivity between conformations in such complex systems is not trivial. Here, we show that multivariate analysis of key structural parameters can identify structural determinants of barrier height by analysis of multiple reaction paths. We apply a well-tested quantum mechanics/molecular mechanics (QM/MM) method to the first step of the acylation reaction between FAAH and oleamide substrate for 36 different starting structures. Geometrical parameters (consisting of the key bond distances that change during the reaction) were collected and used for principal component analysis (PCA), partial least-squares (PLS) regression analysis, and multiple linear regression (MLR) analysis. PCA indicates that different "families" of enzyme-substrate conformations arise from QM/MM molecular dynamics simulation and that rarely sampled, catalytically significant conformational states can be identified. PLS and MLR analyses allowed the construction of linear regression models, correlating the calculated activation barriers with simple geometrical descriptors. These analyses reveal the presence of two fully independent geometrical effects, explaining 78% of the variation in the activation barrier, which are directly correlated with transition-state stabilization (playing a major role in catalysis) and substrate binding. These results highlight the power of statistical approaches of this type in identifying crucial structural features that contribute to enzyme reactivity.

  9. Nuclear localisation of the endocannabinoid metabolizing enzyme fatty acid amide hydrolase (FAAH) in invasive trophoblasts and an association with recurrent miscarriage.

    Science.gov (United States)

    Chamley, L W; Bhalla, A; Stone, P R; Liddell, H; O'Carroll, S; Kearn, C; Glass, M

    2008-11-01

    Endocannabinoids are lipid signalling molecules that are related to the major psychoactive component in marijuana, delta-9-tetrahydrocannabinol and are increasingly recognized as being important in implantation and development of early embryos. The endocannabinoid anandamide, is metabolized by the enzyme fatty acid amide hydrolase (FAAH), and insufficient levels of this enzyme have been implicated in spontaneous miscarriage in women and implantation failure in mice. We screened placental bed biopsies and placental tissue from 45 women with recurrent miscarriage and 17 gestation-matched women with normal pregnancies for the expression of FAAH by immunohistochemistry. Unexpectedly, the enzyme appeared to be localised to the nucleus of trophoblasts and this was confirmed by western blotting of sub-cellular fractions and confocal microscopy. FAAH was expressed in the cytoplasm of large decidual stromal cells and significantly more women with recurrent miscarriage (73%) expressed FAAH in these cells than women with normal pregnancy (31%). FAAH was also expressed in the nucleus of extravillous trophoblasts that had invaded the decidua from 67% of women with recurrent miscarriage but was not expressed by these cells in any women with normal pregnancies. In contrast, FAAH was expressed in extravillous trophoblasts that had migrated out of the villi but that had not yet invaded the decidua in both normal pregnancies and in cases of recurrent miscarriage. FAAH was also present in the nucleus of a small number of villous trophoblasts in some specimens. FAAH appears to be over expressed in trophoblasts that have invaded the decidua, as well as in large decidual stromal cells in many cases of recurrent miscarriage. This may reflect inadequate control of the cannabinoid system in the uterus of women who experience recurrent miscarriages. The functional significance of the unexpected nuclear localisation of FAAH in trophoblasts is not yet clear.

  10. A multi-target approach for pain treatment: dual inhibition of fatty acid amide hydrolase and TRPV1 in a rat model of osteoarthritis.

    Science.gov (United States)

    Malek, Natalia; Mrugala, Monika; Makuch, Wioletta; Kolosowska, Natalia; Przewlocka, Barbara; Binkowski, Marcin; Czaja, Martyna; Morera, Enrico; Di Marzo, Vincenzo; Starowicz, Katarzyna

    2015-05-01

    The pharmacological inhibition of anandamide (AEA) hydrolysis by fatty acid amide hydrolase (FAAH) attenuates pain in animal models of osteoarthritis (OA) but has failed in clinical trials. This may have occurred because AEA also activates transient receptor potential vanilloid type 1 (TRPV1), which contributes to pain development. Therefore, we investigated the effectiveness of the dual FAAH-TRPV1 blocker OMDM-198 in an MIA-model of osteoarthritic pain. We first investigated the MIA-induced model of OA by (1) characterizing the pain phenotype and degenerative changes within the joint using X-ray microtomography and (2) evaluating nerve injury and inflammation marker (ATF-3 and IL-6) expression in the lumbar dorsal root ganglia of osteoarthritic rats and differences in gene and protein expression of the cannabinoid CB1 receptors FAAH and TRPV1. Furthermore, we compared OMDM-198 with compounds acting exclusively on FAAH or TRPV1. Osteoarthritis was accompanied by the fragmentation of bone microstructure and destroyed cartilage. An increase of the mRNA levels of ATF3 and IL-6 and an upregulation of AEA receptors and FAAH in the dorsal root ganglia were observed. OMDM-198 showed antihyperalgesic effects in the OA model, which were comparable with those of a selective TRPV1 antagonist, SB-366,791, and a selective FAAH inhibitor, URB-597. The effect of OMDM-198 was attenuated by the CB1 receptor antagonist, AM-251, and by the nonpungent TRPV1 agonist, olvanil, suggesting its action as an "indirect" CB1 agonist and TRPV1 antagonist. These results suggest an innovative strategy for the treatment of OA, which may yield more satisfactory results than those obtained so far with selective FAAH inhibitors in human OA.

  11. Pharmacological blockade of the fatty acid amide hydrolase (FAAH) alters neural proliferation, apoptosis and gliosis in the rat hippocampus, hypothalamus and striatum in a negative energy context.

    Science.gov (United States)

    Rivera, Patricia; Bindila, Laura; Pastor, Antoni; Pérez-Martín, Margarita; Pavón, Francisco J; Serrano, Antonia; de la Torre, Rafael; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Endocannabinoids participate in the control of neurogenesis, neural cell death and gliosis. The pharmacological effect of the fatty acid amide hydrolase (FAAH) inhibitor URB597, which limits the endocannabinoid degradation, was investigated in the present study. Cell proliferation (phospho-H3(+) or BrdU(+) cells) of the main adult neurogenic zones as well as apoptosis (cleaved caspase-3(+)), astroglia (GFAP(+)), and microglia (Iba1(+) cells) were analyzed in the hippocampus, hypothalamus and striatum of rats intraperitoneally treated with URB597 (0.3 mg/kg/day) at one dose/4-days resting or 5 doses (1 dose/day). Repeated URB597 treatment increased the plasma levels of the N-acylethanolamines oleoylethanolamide, palmitoylethanolamide and arachidonoylethanolamine, reduced the plasma levels of glucose, triglycerides and cholesterol, and induced a transitory body weight decrease. The hippocampi of repeated URB597-treated rats showed a reduced number of phospho-H3(+) and BrdU(+) subgranular cells as well as GFAP(+), Iba1(+) and cleaved caspase-3(+) cells, which was accompanied with decreased hippocampal expression of the cannabinoid CB1 receptor gene Cnr1 and Faah. In the hypothalami of these rats, the number of phospho-H3(+), GFAP(+) and 3-weeks-old BrdU(+) cells was specifically decreased. The reduced striatal expression of CB1 receptor in repeated URB597-treated rats was only associated with a reduced apoptosis. In contrast, the striatum of acute URB597-treated rats showed an increased number of subventricular proliferative, astroglial and apoptotic cells, which was accompanied with increased Faah expression. Main results indicated that FAAH inhibitor URB597 decreased neural proliferation, glia and apoptosis in a brain region-dependent manner, which were coupled to local changes in Faah and/or Cnr1 expression and a negative energy context.

  12. 1-(3-biaryloxy-2-oxopropyl)indole-5-carboxylic acids and related compounds as dual inhibitors of human cytosolic phospholipase A2α and fatty acid amide hydrolase.

    Science.gov (United States)

    Zahov, Stefan; Drews, Andreas; Hess, Mark; Schulze Elfringhoff, Alwine; Lehr, Matthias

    2011-03-07

    Cytosolic phospholipase A2α (cPLA2α) and fatty acid amide hydrolase (FAAH) are enzymes that have emerged as attractive targets for the development of analgesic and anti-inflammatory drugs. We recently reported that 1-[3-(4-octylphenoxy)-2-oxopropyl]indole-5-carboxylic acid (5) is a dual inhibitor of cPLA2α and FAAH. Structure-activity relationship studies revealed that substituents at the indole 3- and 5-positions and replacement of the indole scaffold of this compound by other heterocycles strongly influences the inhibitory potency against cPLA2α and FAAH, respectively. Herein we report the effect of variation of the 4-octyl residue of 5 and an exchange of its carboxylic acid moiety by some bioisosteric functional groups. Several of the compounds assayed were favorably active against both enzymes, and could therefore represent agents with improved analgesic and anti-inflammatory qualities in comparison with selective cPLA2 α and FAAH inhibitors.

  13. Relation of C358A polymorphism of the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH) with obesity and insulin resistance Relación del polimorfismo C358A del enzima del sistema endocanabinoide (hidrolasa amida acida) con la obesidad y la resistencia a la insulina

    OpenAIRE

    D. A. De Luis; M. González Sagrado; Aller, R.; O. Izaola; Conde, R.

    2010-01-01

    Background and aims: Recently, it has been demonstrated that the polymorphism 385 C->A of FAAH (fatty acid amide hydrolase) was associated with overweight and obesity. The aim of our study was to investigate the relationship of missense polymorphism (cDNA 385 C-A) of FAAH gene on obesity anthropometric parameters, cardiovascular risk factors and adipocytokines. Methods: A population of 279 females with obesity (body mass index 30) was analyzed. An indirect calorimetry, tetrapolar electrical b...

  14. Reducing endocannabinoid metabolism with the fatty acid amide hydrolase inhibitor, URB597, fails to modify reinstatement of morphine-induced conditioned floor preference and naloxone-precipitated morphine withdrawal-induced conditioned floor avoidance.

    Science.gov (United States)

    McCallum, Amanda L; Limebeer, Cheryl L; Parker, Linda A

    2010-10-01

    The potential of the fatty acid amide hydrolase (FAAH) inhibitor, URB597, to modify drug prime-induced reinstatement of morphine-induced conditioned floor preference or naloxone-precipitated morphine withdrawal-induced conditioned floor avoidance was evaluated. In Experiment 1, morphine-induced conditioned floor preference was established across 4 conditioning trials. Following extinction training (4 trials), rats were pretreated with URB597 or vehicle prior to a morphine prime or a saline prime. Morphine reinstated the previously extinguished floor preference, but URB597 did not modify the strength of the reinstated preference. In Experiment 2, naloxone-precipitated morphine withdrawal-induced conditioned floor avoidance was established across 2 conditioning trials. Following extinction training (14 trials), rats were pretreated with URB597 or vehicle prior to a saline prime or a morphine withdrawal prime. The morphine withdrawal prime reinstated the previously extinguished floor avoidance, but URB597 did not modify the strength of reinstated avoidance. These results suggest that under the conditions in which URB597 promotes extinction (e.g., Manwell et al. (2009)) it does not interfere with drug-induced reinstatement of either conditioned floor preference or avoidance. That is, although activation of the endocannabinoid (eCB) system promotes extinction of aversive learning, it may not prevent reinstatement of that aversion by re-exposure to the aversive treatment.

  15. The cDNA 385C to A missense polymorphism of the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH) is associated with overweight/obesity but not with binge eating disorder in overweight/obese women.

    Science.gov (United States)

    Monteleone, Palmiero; Tortorella, Alfonso; Martiadis, Vassilis; Di Filippo, Carmela; Canestrelli, Benedetta; Maj, Mario

    2008-05-01

    Endocannabinoids are involved in the modulation of eating behavior; hence, alterations of this system may play a role in obesity. Recently, a single nucleotide polymorphism (cDNA 385C to A) of the gene coding for fatty acid amide hydrolase (FAAH), the major degrading enzyme of endocannabinoids, has been found to be associated with obesity. However, the possibility that the FAAH gene cDNA 385C to A single nucleotide polymorphism (SNP) is associated to binge eating disorder (BED), a condition that frequently occurs in obese individuals, has not been investigated. In order to address this issue, we assessed the distribution of the cDNA 385C to A SNP in 115 overweight/obese subjects with BED, 74 non-BED patients with obesity and 110 normal weight healthy controls. As compared to healthy controls, the whole group of overweight/obese BED and non-BED patients had a significantly higher frequency of the CA genotype and the A allele of the FAAH gene cDNA 385C to A SNP. Moreover, the SNP resulted significantly correlated to the presence of overweight/obesity (F(2, 296)=3.58, P=0.02), but not to the occurrence of BED (F(2, 296)=0.98; P=0.3). The present study confirms previously published significant over-representations of the FAAH 385 A allele in overweight/obese subjects and presents new data in BED patients that the 385 mutation is not significantly associated with BED-related obesity.

  16. Inhibition of fatty acid amide hydrolase and cyclooxygenase-2 increases levels of endocannabinoid related molecules and produces analgesia via peroxisome proliferator-activated receptor-alpha in a model of inflammatory pain.

    Science.gov (United States)

    Jhaveri, Maulik D; Richardson, Denise; Robinson, Ian; Garle, Michael J; Patel, Annie; Sun, Yan; Sagar, Devi R; Bennett, Andrew J; Alexander, Stephen P H; Kendall, David A; Barrett, David A; Chapman, Victoria

    2008-07-01

    The antinociceptive effects of the endocannabinoids (ECs) are enhanced by inhibiting catabolic enzymes such as fatty acid amide hydrolase (FAAH). The physiological relevance of the metabolism of ECs by other pathways, such as cyclooxygenase-2 (COX2) is less clear. To address this question we compared the effects of local inhibition of FAAH versus COX2 (URB597 and nimesulide, respectively) on inflammatory hyperalgesia and levels of endocannabinoids and related molecules in the hindpaw. Inflammatory hyperalgesia was measured following intraplantar injection of carrageenan. Effects of intraplantar injection of URB597 (25 microg and 100 microg) or nimesulide (50 microg) on hyperalgesia and hindpaw levels of anandamide (AEA), 2-arachidonoylglycerol (2AG) and N-palmitoylethanolamine (PEA) were determined. Although both doses of URB597 increased levels of AEA and 2AG in the carrageenan inflamed hindpaw, only the lower dose of URB597 attenuated hyperalgesia (P<0.05). Nimesulide attenuated both hyperalgesia and hindpaw oedema (P<0.001, P<0.01, respectively) and increased levels of PEA (P<0.05) in the hindpaw. Since both AEA and PEA are ligands for peroxisome proliferator-activated receptor-alpha (PPARalpha), the effects of the PPARalpha antagonist GW6471 on nimesulide- and URB597-mediated effects were studied. GW6471, but not a PPARgamma antagonist, blocked the inhibitory effects of nimesulide and URB597 on hyperalgesia. Our data suggest that both COX2 and FAAH play a role in the metabolism of endocannabinoids and related molecules. The finding that PPARalpha antagonism blocked the inhibitory effects of nimesulide and URB597 suggests that PPARalpha contributes to their antinociceptive effects in the carrageenan model of inflammatory hyperalgesia.

  17. The fatty acid amide hydrolase inhibitor URB597 exerts anti-inflammatory effects in hippocampus of aged rats and restores an age-related deficit in long-term potentiation

    Directory of Open Access Journals (Sweden)

    Murphy Niamh

    2012-04-01

    Full Text Available Abstract Background Several factors contribute to the deterioration in synaptic plasticity which accompanies age and one of these is neuroinflammation. This is characterized by increased microglial activation associated with increased production of proinflammatory cytokines like interleukin-1β (IL-1β. In aged rats these neuroinflammatory changes are associated with a decreased ability of animals to sustain long-term potentiation (LTP in the dentate gyrus. Importantly, treatment of aged rats with agents which possess anti-inflammatory properties to decrease microglial activation, improves LTP. It is known that endocannabinoids, such as anandamide (AEA, have anti-inflammatory properties and therefore have the potential to decrease the age-related microglial activation. However, endocannabinoids are extremely labile and are hydrolyzed quickly after production. Here we investigated the possibility that inhibiting the degradation of endocannabinoids with the fatty acid amide hydrolase (FAAH inhibitor, URB597, could ameliorate age-related increases in microglial activation and the associated decrease in LTP. Methods Young and aged rats received subcutaneous injections of the FAAH inhibitor URB597 every second day and controls which received subcutaneous injections of 30% DMSO-saline every second day for 28 days. Long-term potentiation was recorded on day 28 and the animals were sacrificed. Brain tissue was analyzed for markers of microglial activation by PCR and for levels of endocannabinoids by liquid chromatography coupled to tandem mass spectrometry. Results The data indicate that expression of markers of microglial activation, MHCII, and CD68 mRNA, were increased in the hippocampus of aged, compared with young, rats and that these changes were associated with increased expression of the proinflammatory cytokines interleukin (IL-1β and tumor necrosis factor-α (TNFα which were attenuated by treatment with URB597. Coupled with these changes, we

  18. Poly(aspartic acid) (PAA) hydrolases and PAA biodegradation: current knowledge and impact on applications.

    Science.gov (United States)

    Hiraishi, Tomohiro

    2016-02-01

    Thermally synthesized poly(aspartic acid) (tPAA) is a bio-based, biocompatible, biodegradable, and water-soluble polymer that has a high proportion of β-Asp units and equivalent moles of D- and L-Asp units. Poly(aspartic acid) (PAA) hydrolase-1 and hydrolase-2 are tPAA biodegradation enzymes purified from Gram-negative bacteria. PAA hydrolase-1 selectively cleaves amide bonds between β-Asp units via an endo-type process, whereas PAA hydrolase-2 catalyzes the exo-type hydrolysis of the products of tPAA hydrolysis by PAA hydrolase-1. The novel reactivity of PAA hydrolase-1 makes it a good candidate for a biocatalyst in β-peptide synthesis. This mini-review gives an overview of PAA hydrolases with emphasis on their biochemical and functional properties, in particular, PAA hydrolase-1. Functionally related enzymes, such as poly(R-3-hydroxybutyrate) depolymerases and β-aminopeptidases, are compared to PAA hydrolases. This mini-review also provides findings that offer an insight into the catalytic mechanisms of PAA hydrolase-1 from Pedobacter sp. KP-2.

  19. 脑胶质瘤中脂肪酸酰胺水解酶的表达及意义%Expression of fatty acid amide hydrolase in brain glioma and its significance

    Institute of Scientific and Technical Information of China (English)

    张小林; 蒋峰; 龚清永; 韩丽君; 任杰; 林志雄; 傅瑾

    2013-01-01

    Objective To investigate the expression of endocannabinoid metabolic enzyme fatty acid amide hydrolase (FAAH)in human brain glioma tissues and its clinicopathological significance. Methods Twenty-three patients with brain glioma, including one case with grade I, 7 grade II, 5 grade III,2 grade III~IV and 8 glioblastoma, undergoing surgical excision were enrol ed in the study; and 8 samples of normal brain tissues from patients undergoing decompression operation due to cerebral hernia served as controls. qRT-PCR and HPLC-MS were used to detect the mRNA and the activity of FAAH, respec-tively. Results The expression of mRNA and activity of FAAH was significantly higher in low grade (gradeⅠ~Ⅱ) and high grade (gradeⅢ~Ⅳ) brain glioma than those in the normal brain tissues (P<0.01). The expression of FAAH mRNA was positively corre-lated with the FAAH Activity,and both were negatively correlated with the pathological grades (P<0.01). Conclusion FAAH may be involved in the occurrence and development of brain glioma;the detection of FAAH expression may be of value in evaluation of biological behavior and prognosis of brain glioma.%  目的研究内源性大麻素代谢酶脂肪酸酰胺水解酶(FAAH)在脑胶质瘤组织中的表达情况及其与胶质瘤病理级别的关系,探讨其临床意义.方法选取首次手术切除并经病理检查证实的脑胶质瘤标本23例,其中WHOⅠ级1例,Ⅱ级7例,Ⅲ级5例,Ⅲ~Ⅳ级2例,Ⅳ级8例.另取8例因颅脑外伤行内减压术切除的正常脑组织作为对照.应用实时荧光定量PCR和高效液相色谱-质谱联用技术分别检测各组织标本中FAAH mRNA和FAAH活性的表达.结果 FAAH mRNA、FAAH活性在低级别(WHOⅠ~Ⅱ级)和高级别(WHOⅢ~Ⅳ级)脑胶质瘤组织中的表达水平较正常脑组织明显降低,差异有统计学意义(均P<0.01),且随着肿瘤病理级别的增高而降低,与肿瘤的病理分级呈负相关(均P<0.01).FAAH mRNA与FAAH活性

  20. Structural insights into the specific recognition of N-heterocycle biodenitrogenation-derived substrates by microbial amide hydrolases.

    Science.gov (United States)

    Wu, Geng; Chen, Duoduo; Tang, Hongzhi; Ren, Yiling; Chen, Qihua; Lv, Yang; Zhang, Zhenyi; Zhao, Yi-Lei; Yao, Yuxiang; Xu, Ping

    2014-03-01

    N-heterocyclic compounds from industrial wastes, including nicotine, are environmental pollutants or toxicants responsible for a variety of health problems. Microbial biodegradation is an attractive strategy for the removal of N-heterocyclic pollutants, during which carbon-nitrogen bonds in N-heterocycles are converted to amide bonds and subsequently severed by amide hydrolases. Previous studies have failed to clarify the molecular mechanism through which amide hydrolases selectively recognize diverse amide substrates and complete the biodenitrogenation process. In this study, structural, computational and enzymatic analyses showed how the N-formylmaleamate deformylase Nfo and the maleamate amidase Ami, two pivotal amide hydrolases in the nicotine catabolic pathway of Pseudomonas putida S16, specifically recognize their respective substrates. In addition, comparison of the α-β-α groups of amidases, which include Ami, pinpointed several subgroup-characteristic residues differentiating the two classes of amide substrates as containing either carboxylate groups or aromatic rings. Furthermore, this study reveals the molecular mechanism through which the specially tailored active sites of deformylases and amidases selectively recognize their unique substrates. Our work thus provides a thorough elucidation of the molecular mechanism through which amide hydrolases accomplish substrate-specific recognition in the microbial N-heterocycles biodenitrogenation pathway.

  1. Bacterial Cyanuric Acid Hydrolase for Water Treatment.

    Science.gov (United States)

    Yeom, Sujin; Mutlu, Baris R; Aksan, Alptekin; Wackett, Lawrence P

    2015-10-01

    Di- and trichloroisocyanuric acids are widely used as water disinfection agents, but cyanuric acid accumulates with repeated additions and must be removed to maintain free hypochlorite for disinfection. This study describes the development of methods for using a cyanuric acid-degrading enzyme contained within nonliving cells that were encapsulated within a porous silica matrix. Initially, three different bacterial cyanuric acid hydrolases were compared: TrzD from Acidovorax citrulli strain 12227, AtzD from Pseudomonas sp. strain ADP, and CAH from Moorella thermoacetica ATCC 39073. Each enzyme was expressed recombinantly in Escherichia coli and tested for cyanuric acid hydrolase activity using freely suspended or encapsulated cell formats. Cyanuric acid hydrolase activities differed by only a 2-fold range when comparing across the different enzymes with a given format. A practical water filtration system is most likely to be used with nonviable cells, and all cells were rendered nonviable by heat treatment at 70°C for 1 h. Only the CAH enzyme from the thermophile M. thermoacetica retained significant activity under those conditions, and so it was tested in a flowthrough system simulating a bioreactive pool filter. Starting with a cyanuric acid concentration of 10,000 μM, more than 70% of the cyanuric acid was degraded in 24 h, it was completely removed in 72 h, and a respike of 10,000 μM cyanuric acid a week later showed identical biodegradation kinetics. An experiment conducted with water obtained from municipal swimming pools showed the efficacy of the process, although cyanuric acid degradation rates decreased by 50% in the presence of 4.5 ppm hypochlorite. In total, these experiments demonstrated significant robustness of cyanuric acid hydrolase and the silica bead materials in remediation.

  2. Unraveling the degradation of artificial amide bonds in nylon oligomer hydrolase: from induced-fit to acylation processes.

    Science.gov (United States)

    Baba, Takeshi; Boero, Mauro; Kamiya, Katsumasa; Ando, Hiroyuki; Negoro, Seiji; Nakano, Masayoshi; Shigeta, Yasuteru

    2015-02-14

    To elucidate how the nylon oligomer hydrolase (NylB) acquires its peculiar degradation activity towards non-biological amide bonds, we inspected the underlying enzymatic processes going from the induced-fit upon substrate binding to acylation. Specifically we investigated the mutational effects of two mutants, Y170F and D181G, indicated in former experiments as crucial systems because of their specific amino acid residues. Therefore, by adopting first-principles molecular dynamics complemented with metadynamics we provide a detailed insight into the underlying acylation mechanism. Our results show that while in the wild type (WT) the Tyr170 residue points the NH group towards the proton-acceptor site of an artificial amide bond, hence ready to react, in the Y170F this does not occur. The reason is ascribed to the absence of Tyr170 in the mutant, which is replaced by phenylalanine, which is unable to form hydrogen bond with the amide bond; thus, resulting in an increase in the activation barrier of more than 10 kcal mol(-1). Nonetheless, despite the lack of hydrogen bonding between the Y170F and the substrate, the highest free energy barrier for the induced-fit is similar to that of WT. This seems to suggest that in the induced-fit process, kinetics is little affected by the mutation. On the basis of additional structural homology analyses on the enzymes of the same family, we suggest that natural selection is responsible for the development of the peculiar hydrolytic activity of Arthrobacter sp. KI72.

  3. Metabolism of amino acid amides in Pseudomonas putida ATCC 12633

    NARCIS (Netherlands)

    Hermes, H.F.M.; Croes, L.M.; Peeters, W.P.H.; Peters, P.J.H.; Dijkhuizen, L.

    1993-01-01

    The metabolism of the natural amino acid L-valine, the unnatural amino acids D-valine, and D-, L-phenylglycine (D-, L-PG), and the unnatural amino acid amides D-, L-phenylglycine amide (D, L-PG-NH2) and L-valine amide (L-Val-NH2) was studied in Pseudomonas putida ATCC 12633. The organism possessed c

  4. Microorganisms hydrolyse amide bonds; knowledge enabling read-across of biodegradability of fatty acid amides.

    Science.gov (United States)

    Geerts, Roy; Kuijer, Patrick; van Ginkel, Cornelis G; Plugge, Caroline M

    2014-07-01

    To get insight in the biodegradation and potential read-across of fatty acid amides, N-[3-(dimethylamino)propyl] cocoamide and N-(1-ethylpiperazine) tall oil amide were used as model compounds. Two bacteria, Pseudomonas aeruginosa PK1 and Pseudomonas putida PK2 were isolated with N-[3-(dimethylamino)propyl] cocoamide and its hydrolysis product N,N-dimethyl-1,3-propanediamine, respectively. In mixed culture, both strains accomplished complete mineralization of N-[3-(dimethylamino)propyl] cocoamide. Aeromonas hydrophila PK3 was enriched with N-(1-ethylpiperazine) tall oil amide and subsequently isolated using agar plates containing dodecanoate. N-(2-Aminoethyl)piperazine, the hydrolysis product of N-(1-ethylpiperazine) tall oil amide, was not degraded. The aerobic biodegradation pathway for primary and secondary fatty acid amides of P. aeruginosa and A. hydrophila involved initial hydrolysis of the amide bond producing ammonium, or amines, where the fatty acids formed were immediately metabolized. Complete mineralization of secondary fatty acid amides depended on the biodegradability of the released amine. Tertiary fatty acid amides were not transformed by P. aeruginosa or A. hydrophila. These strains were able to utilize all tested primary and secondary fatty acid amides independent of the amine structure and fatty acid. Read-across of previous reported ready biodegradability results of primary and secondary fatty acid amides is justified based on the broad substrate specificity and the initial hydrolytic attack of the two isolates PK1 and PK3.

  5. Structure-activity relationships of amide-phosphonate derivatives as inhibitors of the human soluble epoxide hydrolase.

    Science.gov (United States)

    Kim, In-Hae; Park, Yong-Kyu; Nishiwaki, Hisashi; Hammock, Bruce D; Nishi, Kosuke

    2015-11-15

    Structure-activity relationships of amide-phosphonate derivatives as inhibitors of the human soluble epoxide hydrolase (sEH) were investigated. First, a series of alkyl or aryl groups were substituted on the carbon alpha to the phosphonate function in amide compounds to see whether substituted phosphonates can act as a secondary pharmacophore. A tert-butyl group (16) on the alpha carbon was found to yield most potent inhibition on the target enzyme. A 4-50-fold drop in inhibition was induced by other substituents such as aryls, substituted aryls, cycloalkyls, and alkyls. Then, the modification of the O-substituents on the phosphonate function revealed that diethyl groups (16 and 23) were preferable for inhibition to other longer alkyls or substituted alkyls. In amide compounds with the optimized diethylphosphonate moiety and an alkyl substitution such as adamantane (16), tetrahydronaphthalene (31), or adamantanemethane (36), highly potent inhibitions were gained. In addition, the resulting potent amide-phosphonate compounds had reasonable water solubility, suggesting that substituted phosphonates in amide inhibitors are effective for both inhibition potency on the human sEH and water solubility as a secondary pharmacophore.

  6. Gas-phase Acidities of Aspartic Acid, Glutamic Acid, and their Amino Acid Amides.

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhong; Matus, Myrna H; Velazquez, Hector A; Dixon, David A; Cassady, Carolyn J

    2007-02-14

    Gas-phase acidities (GA or ΔGacid) for the two most acidic common amino acids, aspartic acid and glutamic acid, have been determined for the first time. Because of the amide linkage’s importance in peptides and as an aid in studying side chain versus main chain deprotonation, aspartic acid amide and glutamic acid amide were also studied. Experimental GA values were measured by proton transfer reactions in an electrospray ionization/Fourier transform ion cyclotron resonance mass spectrometer. Calculated GAs were obtained by density functional and molecular orbital theory approaches. The best agreement with experiment was found at the G3MP2 level; the MP2/CBS and B3LYP/aug-cc-pVDZ results are 3–4 kcal/mol more acidic than the G3MP2 results. Experiment shows that aspartic acid is more acidic than glutamic acid by ca. 3 kcal/mol whereas the G3MP2 results show a smaller acidity difference of 0.2 kcal/mol. Similarly, aspartic acid amide is experimentally observed to be ca. 2 kcal/mol more acidic than glutamic acid amide whereas the G3MP2 results show a correspondingly smaller energy difference of 0.7 kcal/mol. The computational results clearly show that the anions are all ring-like structures with strong hydrogen bonds between the OH or NH2 groups and the CO2- group from which the proton is removed. The two amino acids are main-chain deprotonated. In addition, use of the COSMO model for the prediction of the free energy differences in aqueous solution gave values in excellent agreement with the most recent experimental values for pKa. Glutamic acid is predicted to be more acidic than aspartic acid in aqueous solution due to differential solvation effects.

  7. Gas-phase acidities of aspartic acid, glutamic acid, and their amino acid amides

    Science.gov (United States)

    Li, Zhong; Matus, Myrna H.; Velazquez, Hector Adam; Dixon, David A.; Cassady, Carolyn J.

    2007-09-01

    Gas-phase acidities (GA or [Delta]Gacid) for the two most acidic common amino acids, aspartic acid and glutamic acid, have been determined for the first time. Because of the amide linkage's importance in peptides and as an aid in studying side chain versus main chain deprotonation, aspartic acid amide and glutamic acid amide were also studied. Experimental GA values were measured by proton transfer reactions in an electrospray ionization/Fourier transform ion cyclotron resonance mass spectrometer. Calculated GAs were obtained by density functional and molecular orbital theory approaches. The best agreement with experiment was found at the G3MP2 level; the MP2/CBS and B3LYP/aug-cc-pVDZ results are 3-4 kcal/mol more acidic than the G3MP2 results. Experiment shows that aspartic acid is more acidic than glutamic acid by ca. 3 kcal/mol whereas the G3MP2 results show a smaller acidity difference of 0.2 kcal/mol. Similarly, aspartic acid amide is experimentally observed to be ca. 2 kcal/mol more acidic than glutamic acid amide whereas the G3MP2 results show a correspondingly smaller energy difference of 0.7 kcal/mol. The computational results clearly show that the anions are all ring-like structures with strong hydrogen bonds between the OH or NH2 groups and the CO2- group from which the proton is removed. The two amino acids are main-chain deprotonated. In addition, use of the COSMO model for the prediction of the free energy differences in aqueous solution gave values in excellent agreement with the most recent experimental values for pKa. Glutamic acid is predicted to be more acidic than aspartic acid in aqueous solution due to differential solvation effects.

  8. Relation of C358A polymorphism of the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH with obesity and insulin resistance Relación del polimorfismo C358A del enzima del sistema endocanabinoide (hidrolasa amida acida con la obesidad y la resistencia a la insulina

    Directory of Open Access Journals (Sweden)

    D. A. de Luis

    2010-12-01

    Full Text Available Background and aims: Recently, it has been demonstrated that the polymorphism 385 C->A of FAAH (fatty acid amide hydrolase was associated with overweight and obesity. The aim of our study was to investigate the relationship of missense polymorphism (cDNA 385 C-A of FAAH gene on obesity anthropometric parameters, cardiovascular risk factors and adipocytokines. Methods: A population of 279 females with obesity (body mass index 30 was analyzed. An indirect calorimetry, tetrapolar electrical bioimpedance, blood pressure, a serial assessment of nutritional intake with 3 days written food records and biochemical analysis (lipid profile, adipocytokines, insulin, CRP and lipoprotein-a were performed. The statistical analysis was performed for the combined C385A and A385A as a group and wild type C385C as second group. Results: One hundred and ninety four patients (69.5% had the genotype C385C (wild type group and 76 (27.2% patients had the genotype C358A or A358A (9 patients, 3.2% (mutant type group. No differences were detected between groups in anthropometric parameters and dietary intakes. Triglycerides (118.9 ± 59.9 mg/dl vs 107.4 + 51.3 mg/dl;p Antecedentes y objetivos: Recientemente, se ha demostrado que el polimorfismo 385 C/A, de FAAH (hidrolasa amida de ácidos grasos se asocia con el sobrepeso y la obesidad. El objetivo de nuestro estudio fue investigar la relación de este polimorfismo del gen de FAAH con parámetros antropométricos, factores de riesgo cardiovascular y adipocitoquinas. Métodos: Una población de 279 mujeres con obesidad (índice de masa corporal> 30 fue analizada. Se realizaron las siguientes determinaciones; calorimetría indirecta, bioimpedancia eléctrica, presión arterial, una evaluación de la ingesta nutricional de 3 días, así como un análisis bioquímico (perfil lipídico, adipocitoquinas, insulina, proteina C reactiva y lipoproteína-(a. El análisis estadístico se realizó combinando C385A y A385A como grupo

  9. New Umami Amides: Structure-Taste Relationship Studies of Cinnamic Acid Derived Amides and the Natural Occurrence of an Intense Umami Amide in Zanthoxylum piperitum.

    Science.gov (United States)

    Frerot, Eric; Neirynck, Nathalie; Cayeux, Isabelle; Yuan, Yoyo Hui-Juan; Yuan, Yong-Ming

    2015-08-19

    A series of aromatic amides were synthesized from various acids and amines selected from naturally occurring structural frameworks. These synthetic amides were evaluated for umami taste in comparison with monosodium glutamate. The effect of the substitution pattern of both the acid and the amine parts on umami taste was investigated. The only intensely umami-tasting amides were those made from 3,4-dimethoxycinnamic acid. The amine part was more tolerant to structural changes. Amides bearing an alkyl- or alkoxy-substituted phenylethylamine residue displayed a clean umami taste as 20 ppm solutions in water. Ultraperformance liquid chromatography coupled with a high quadrupole-Orbitrap mass spectrometer (UPLC/MS) was subsequently used to show the natural occurrence of these amides. (E)-3-(3,4-Dimethoxyphenyl)-N-(4-methoxyphenethyl)acrylamide was shown to occur in the roots and stems of Zanthoxylum piperitum, a plant of the family Rutaceae growing in Korea, Japan, and China.

  10. Reaction mechanism of the acidic hydrolysis of highly twisted amides: Rate acceleration caused by the twist of the amide bond.

    Science.gov (United States)

    Mujika, Jon I; Formoso, Elena; Mercero, Jose M; Lopez, Xabier

    2006-08-03

    We present an ab initio study of the acid hydrolysis of a highly twisted amide and a planar amide analogue. The aim of these studies is to investigate the effect that the twist of the amide bond has on the reaction barriers and mechanism of acid hydrolysis. Concerted and stepwise mechanisms were investigated using density functional theory and polarizable continuum model calculations. Remarkable differences were observed between the mechanism of twisted and planar amide, due mainly to the preference for N-protonation of the former and O-protonation of the latter. In addition, we were also able to determine that the hydrolytic mechanism of the twisted amide will be pH dependent. Thus, there is a preference for a stepwise mechanism with formation of an intermediate in the acid hydrolysis, whereas the neutral hydrolysis undergoes a concerted-type mechanism. There is a nice agreement between the characterized intermediate and available X-ray data and a good agreement with the kinetically estimated rate acceleration of hydrolysis with respect to analogous undistorted amide compounds. This work, along with previous ab initio calculations, describes a complex and rich chemistry for the hydrolysis of highly twisted amides as a function of pH. The theoretical data provided will allow for a better understanding of the available kinetic data of the rate acceleration of amides upon twisting and the relation of the observed rate acceleration with intrinsic differential reactivity upon loss of amide bond resonance.

  11. Intramolecular Amide Hydrolysis in N-Methylmaleamic Acid Revisited

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The intramolecular amide hydrolysis of N-methylmaleamic acid have been revisited by use of density functional theory and inclusion of solvent effects. The results indicate that concerted reaction mechanism is favored over stepwise reaction mechanism. This is in agreement with the previous theoretical study. Sovlent effects have significant influence on the reaction barrier.

  12. 40 CFR 721.720 - Alkoxylated fatty acid amide, alkylsulfate salt.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkoxylated fatty acid amide... Specific Chemical Substances § 721.720 Alkoxylated fatty acid amide, alkylsulfate salt. (a) Chemical... as an alkoxylated fatty acid amide, alkylsulfate salt (PMN P-97-136) is subject to reporting...

  13. Retinobenzoic acids. 4. Conformation of aromatic amides with retinoidal activity. Importance of trans-amide structure for the activity.

    Science.gov (United States)

    Kagechika, H; Himi, T; Kawachi, E; Shudo, K

    1989-10-01

    N-Methylation of two retinoidal amide compounds, 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carbamoyl]benz oic acid (3, Am80) and 4-[[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2- naphthalenyl)carbonyl]amino]benzoic acid (5, Am580), resulted in the disappearance of their potent differentiation-inducing activity on human promyelocytic leukemia cell line HL-60. Studies with 1H NMR and UV spectroscopy indicated that large conformational differences exist between the active secondary amides and the inactive N-methyl amides. From a comparison of the spectroscopic results of these amides with those of stilbene derivatives, the conformations of the active amides are expected to resemble that of (E)-stilbene, whereas the inactive amides resemble the Z isomer: 3 (Am80) and 5 (Am580) have a trans-amide bond and their whole structures are elongated, while the N-methylated compounds [4 (Am90) and 6 (Am590)] have a cis-amide bond, resulting in the folding of the two benzene rings. These structures in the crystals were related to those in solution by 13C NMR spectroscopic comparison between the two phases (solid and solution).

  14. Accumulation of hydroxycinnamic acid amides in winter wheat under snow.

    Science.gov (United States)

    Jin, Shigeki; Yoshida, Midori; Nakajima, Takashi; Murai, Akio

    2003-06-01

    It was found that the content of antifungal compounds p-coumaroylagmatine [1-(trans-4'-hydroxycinnamoylamino)-4-guanidinobutane] and p-coumaroyl-3-hydroxyagmatine [1-(trans-4'-hydroxycinnamoylamino)-3-hydroxy-4-guanidinobutane] in the crown of winter wheat (Triticum aestivum L. cv Chihokukomugi) significantly increased under snow cover. This finding suggests that the accumulation of these hydroxycinnamic acid amides was caused by winter stress and related to protecting the plant against snow mold under snow cover.

  15. Probing ligand-binding modes and binding mechanisms of benzoxazole-based amide inhibitors with soluble epoxide hydrolase by molecular docking and molecular dynamics simulation.

    Science.gov (United States)

    Chen, Hang; Zhang, Ying; Li, Liang; Han, Ju-Guang

    2012-08-30

    Soluble epoxide hydrolase (sEH) has become a new therapeutic target for treating a variety of human diseases. The inhibition of human sEH hydrolase activity was studied by molecular docking and molecular dynamics (MD) simulation techniques. A set of six benzoxazole-based amide inhibitors binding to sEH has been studied through molecular docking, MD simulation, free energy calculations, and energy decomposition analysis. On the basis of molecular mechanics-generalized Born/surface area (MM-GB/SA) computation and normal-mode analysis (NMA), the obtained results indicate that the rank of calculated binding free energies (ΔΔGTOT) of these inhibitors is in excellent agreement with that of experimental bioactivity data (IC50). The correlation coefficient (r(2)) between the predicted ΔΔGTOT and IC50 is 0.88. van der Waals energies are the largest component of the total energies, and the entropy changes play an indispensable role in determining the ΔΔGTOT. Rational binding modes were discussed and determined by the docking results and binding free energies. The free energy decomposition of each residue reveals that the residue Trp334 dominates the most binding free energies among all residues and that the activities for these molecules to the sEH are not decided by hydrogen bonds or a certain residue but by the common effect of multiple side chains in the active site.

  16. Stability of caffeic acid phenethyl amide (CAPA) in rat plasma.

    Science.gov (United States)

    Yang, John; Kerwin, Sean M; Bowman, Phillip D; Stavchansky, Salomon

    2012-05-01

    A validated C₁₈ reverse-phase HPLC method with UV detection at 320 nm was developed and used for the stability evaluation of caffeic acid phenethyl amide (CAPA) and caffeic acid phenethyl ester (CAPE) in rat plasma. CAPA is the amide derivative of CAPE, a naturally occurring polyphenolic compound that has been found to be active in a variety of biological pathways. CAPA has been shown to protect endothelial cells against hydrogen peroxide-induced oxidative stress to a similar degree to CAPE. CAPE has been reported to be rapidly hydrolyzed in rat plasma via esterase enzymes. CAPA is expected to display a longer half-life than CAPE by avoiding hydrolysis via plasma esterases. The stability of CAPA and CAPE in rat plasma was investigated at three temperatures. The half-lives for CAPA were found to be 41.5, 10 and 0.82 h at 25, 37 and 60 °C, respectively. The half-lives for CAPE were found to be 1.95, 0.35 and 0.13 h at 4, 25 and 37 °C, respectively. The energy of activation was found to be 22.1 kcal/mol for CAPA and 14.1 kcal/mol for CAPE. A more stable compound could potentially extend the beneficial effects of CAPE.

  17. Porphyrin amino acids-amide coupling, redox and photophysical properties of bis(porphyrin) amides.

    Science.gov (United States)

    Melomedov, Jascha; Wünsche von Leupoldt, Anica; Meister, Michael; Laquai, Frédéric; Heinze, Katja

    2013-07-14

    New trans-AB2C meso-substituted porphyrin amino acid esters with meso-substituents of tunable electron withdrawing power (B = mesityl, 4-C6H4F, 4-C6H4CF3, C6F5) were prepared as free amines 3a-3d, as N-acetylated derivatives Ac-3a-Ac-3d and corresponding zinc(II) complexes Zn-Ac-3a-Zn-Ac-3d. Several amide-linked bis(porphyrins) with a tunable electron density at each porphyrin site were obtained from the amino porphyrin precursors by condensation reactions (4a-4d) and mono- and bis(zinc(II)) complexes Zn(2)-4d and Zn(1)Zn(2)-4d were prepared. The electronic interaction between individual porphyrin units in bis(porphyrins) 4 is probed by electrochemical experiments (CV, EPR), electronic absorption spectroscopy, steady-state and time-resolved fluorescence spectroscopy in combination with DFT/PCM calculations on diamagnetic neutral bis(porphyrins) 4 and on respective charged mixed-valent radicals 4(+/-). The interaction via the -C6H4-NHCO-C6H4- bridge, the site of oxidation and reduction and the lowest excited singlet state S1, is tuned by the substituents on the individual porphyrins and the metalation state.

  18. Poly(ester amide)s based on (L)-lactic acid oligomers and α-amino acids: influence of the α-amino acid side chain in the poly(ester amide)s properties.

    Science.gov (United States)

    Fonseca, Ana C; Coelho, Jorge F J; Valente, Joana F A; Correia, Tiago R; Correia, Ilídio J; Gil, Maria H; Simões, Pedro N

    2013-01-01

    Novel biodegradable and low cytotoxic poly(ester amide)s (PEAs) based on α-amino acids and (L)-lactic acid (L-LA) oligomers were successfully synthesized by interfacial polymerization. The chemical structure of the new polymers was confirmed by spectroscopic analyses. Further characterization suggests that the α-amino acid plays a critical role on the final properties of the PEA. L-phenylalanine provides PEAs with higher glass transition temperature, whereas glycine enhances the crystallinity. The hydrolytic degradation in PBS (pH = 7.4) at 37 °C also depends on the α-amino acid, being faster for glycine-based PEAs. The cytotoxic profiles using fibroblast human cells indicate that the PEAs did not elicit an acute cytotoxic effect. The strategy presented in this work opens the possibility of synthesizing biodegradable PEAs with low citotoxicity by an easy and fast method. It is worth to mention also that the properties of these materials can be fine-tuned only by changing the α-amino acid.

  19. Mechanism of arylboronic acid-catalyzed amidation reaction between carboxylic acids and amines.

    Science.gov (United States)

    Wang, Chen; Yu, Hai-Zhu; Fu, Yao; Guo, Qing-Xiang

    2013-04-07

    Arylboronic acids were found to be efficient catalysts for the amidation reactions between carboxylic acids and amines. Theoretical calculations have been carried out to investigate the mechanism of this catalytic process. It is found that the formation of the acyloxyboronic acid intermediates from the carboxylic acid and the arylboronic acid is kinetically facile but thermodynamically unfavorable. Removal of water (as experimentally accomplished by using molecular sieves) is therefore essential for overall transformation. Subsequently C-N bond formation between the acyloxyboronic acid intermediates and the amine occurs readily to generate the desired amide product. The cleavage of the C-O bond of the tetracoordinate acyl boronate intermediates is the rate-determining step in this process. Our analysis indicates that the mono(acyloxy)boronic acid is the key intermediate. The high catalytic activity of ortho-iodophenylboronic acid is attributed to the steric effect as well as the orbital interaction between the iodine atom and the boron atom.

  20. Comparison of pH-sensitive degradability of maleic acid amide derivatives.

    Science.gov (United States)

    Kang, Sunyoung; Kim, Youngeun; Song, Youngjun; Choi, Jin Uk; Park, Euddeum; Choi, Wonmin; Park, Jeongseon; Lee, Yan

    2014-05-15

    We synthesized five maleic acid amide derivatives (maleic, citraconic, cis-aconitic, 2-(2'-carboxyethyl) maleic, 1-methyl-2-(2'-carboxyethyl) maleic acid amide), and compared their degradability for the future development of pH-sensitive biomaterials with tailored kinetics of the release of drugs, the change of charge density, and the degradation of scaffolds. The degradation kinetics was highly dependent upon the substituents on the cis-double bond. Among the maleic acid amide derivatives, 2-(2'-carboxyethyl) maleic acid amide with one carboxyethyl and one hydrogen substituent showed appropriate degradability at weakly acidic pH, and the additional carboxyl group can be used as a pH-sensitive linker.

  1. Structure of the Cyanuric Acid Hydrolase TrzD Reveals Product Exit Channel

    Energy Technology Data Exchange (ETDEWEB)

    Bera, Asim K.; Aukema, Kelly G.; Elias, Mikael; Wackett, Lawrence P.

    2017-03-27

    Cyanuric acid hydrolases are of industrial importance because of their use in aquatic recreational facilities to remove cyanuric acid, a stabilizer for the chlorine. Degradation of excess cyanuric acid is necessary to maintain chlorine disinfection in the waters. Cyanuric acid hydrolase opens the cyanuric acid ring hydrolytically and subsequent decarboxylation produces carbon dioxide and biuret. In the present study, we report the X-ray structure of TrzD, a cyanuric acid hydrolase from Acidovorax citrulli. The crystal structure at 2.19 Å resolution shows a large displacement of the catalytic lysine (Lys163) in domain 2 away from the active site core, whereas the two other active site lysines from the two other domains are not able to move. The lysine displacement is proposed here to open up a channel for product release. Consistent with that, the structure also showed two molecules of the co-product, carbon dioxide, one in the active site and another trapped in the proposed exit channel. Previous data indicated that the domain 2 lysine residue plays a role in activating an adjacent serine residue carrying out nucleophilic attack, opening the cyanuric acid ring, and the mobile lysine guides products through the exit channel.

  2. Peptidoglycan Hydrolases of Local Lactic Acid Bacteria from Kazakh Traditional Food

    Directory of Open Access Journals (Sweden)

    Serik Shaikhin

    2014-01-01

    Full Text Available Introduction: Peptidoglycan (PG is a major component of the cell wall of Gram-positive bacteria and is essential for maintaining the integrity of the bacterial cell and its shape. The bacteria synthesize PG hydrolases, which are capable of cleaving the covalent bonds of PG. They also play an important role in modeling PG, which is required for bacterial growth and division. In an era of increasing antibiotic-resistant pathogens, PG hydrolases that destroy these important structures of the cell wall act as a potential source of new antimicrobials. The aim of this study is to identify the main PG hydrolases of local lactic acid bacteria isolated from traditional foods that enhance probiotic activity of a biological preparation. Methods. Lactococcus lactis 17А and Lactococcus garvieae 19А were isolated from the traditional sausage-like meat product called kazy. They were isolated according to standards methods of microbiology. Genetic identification of the isolates were tested by determining the nucleotide sequences of 16S rDNA. The Republican collection of microorganisms took strains of Lactobacillus casei subsp. Rhamnosus 13-P, L. delbrueckii subsp. lactis CG-1 B-RKM 0044 from cheese, Lactobacillus casei subsp. casei B-RKM 0202 from homemade butter. They used the standard technique of renaturating polyacrylamide gel electrophoresis to detect PG hydrolases activity. Results. According to the profiles of PG hydrolase activity on zymograms, the enzymes of Lactococci 17A and 19A in kazy are similar in electrophoretic mobility to major autolysin AcmA, while the lactobacilli of industrial and home-made dairy products have enzymes similar to extracellular proteins p40 and p75, which have probiotic activity. Conclusions. Use of peptidoglycan hydrolases seems to be an interesting approach in the fight against multi-drug resistant strains of bacteria and could be a valuable tool for the treatment of diseases caused by these microorganisms in Kazakhstan.

  3. Purification and characterization of a chlorogenic acid hydrolase from Aspergillus niger catalysing the hydrolysis of chlorogenic acid.

    Science.gov (United States)

    Asther, Michèle; Estrada Alvarado, Maria Isabel; Haon, Mireille; Navarro, David; Asther, Marcel; Lesage-Meessen, Laurence; Record, Eric

    2005-01-12

    Among 15 Aspergillus strains, Aspergillus niger BRFM 131 was selected for its high chlorogenic acid hydrolase activity. The enzyme was purified and characterized with respect to its physico-chemical and kinetic properties. Four chromatographic steps were necessary to purify the protein to homogeneity with a recovery of 2%. Km of the chlorogenic acid hydrolase was estimated to be 10 microM against chlorogenic acid as substrate. Under native conditions, the protein presented a molecular mass of 170 kDa, and SDS-PAGE analysis suggested the presence of two identical 80 kDa subunits. Isoelectric point was 6.0; pH optimum for activity was determined to be 6.0 and temperature optima to be 55 degrees C. The N-terminal sequence did not present any homology with other cinnamoyl ester hydrolases previously described suggesting the purification of a new protein. The chlorogenic acid hydrolase was used successfully for the production of caffeic acid, which possesses strong antioxidant properties, from natural substrates specially rich in chlorogenic acid like apple marc and coffee pulp.

  4. Retinoic acid amide inhibits JAK/STAT pathway in lung cancer which leads to apoptosis.

    Science.gov (United States)

    Li, Hong-Xing; Zhao, Wei; Shi, Yan; Li, Ya-Na; Zhang, Lian-Shuang; Zhang, Hong-Qin; Wang, Dong

    2015-11-01

    Small cell lung cancer (SCLC) accounts for 12 to 16% of lung neoplasms and has a high rate of metastasis. The present study demonstrates the antiproliferative effect of retinoic acid amide in vitro and in vivo against human lung cancer cells. The results from MTT assay showed a significant growth inhibition of six tested lung cancer cell lines and inhibition of clonogenic growth at 30 μM. Retinoic acid amide also leads to G2/M-phase cell cycle arrest and apoptosis of lung cancer cells. It caused inhibition of JAK2, STAT3, and STAT5, increased the level of p21WAF1, and decreased cyclin A, cyclin B1, and Bcl-XL expression. Retinoic acid amide exhibited a synergistic effect on antiproliferative effects of methotrexate in lung cancer cells. In lung tumor xenografts, the tumor volume was decreased by 82.4% compared to controls. The retinoic acid amide-treated tumors showed inhibition of JAK2/STAT3 activation and Bcl-XL expression. There was also increase in expression of caspase-3 and caspase-9 in tumors on treatment with retinoic acid amide. Thus, retinoic acid amide exhibits promising antiproliferative effects against human lung cancer cells in vitro and in vivo and enhances the antiproliferative effect of methotrexate.

  5. Syntheses of Macrocyclic Amides from L-Amino Acid Esters by RCM

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A series of succinate-derived macrocyclic amides( 1 ) was synthesized via ring-closing metathesis (RCM) as the key step. The substrate included 12 to 15 members. The metathesis precursors were obtained from the amide coupling of tert-butyl 3-carboxyhex-5-enoate(2) with numerous side-chain alkenylated amino acid esters of general type(3)derived from L-lysine and L-ornithine.

  6. Synthesis and characterization of some N-substituted amides of salicylic acid

    OpenAIRE

    Lupea Xenia Alfa; Padure Mirabela

    2003-01-01

    The synthesis of some N-substituted aromatic amides in the salicylic acid series was achieved, by direct reaction between primary amines and salicylic acid in inert organic solvent, in the presence of PCl3. The compounds that were obtained, partially not described in literature, were characterized by chemical-physical methods.

  7. Synthesis and characterization of some N-substituted amides of salicylic acid

    Directory of Open Access Journals (Sweden)

    Lupea Xenia Alfa

    2003-01-01

    Full Text Available The synthesis of some N-substituted aromatic amides in the salicylic acid series was achieved, by direct reaction between primary amines and salicylic acid in inert organic solvent, in the presence of PCl3. The compounds that were obtained, partially not described in literature, were characterized by chemical-physical methods.

  8. One pot direct synthesis of amides or oxazolines from carboxylic acids using Deoxo-Fluor reagent.

    Science.gov (United States)

    Kangani, Cyrous O; Kelley, David E

    2005-12-19

    A mild and highly efficient one pot-one step condensation and/or condensation-cyclization of various acids to amides and/or oxazolines using Deoxo-Fluor reagents is described. Parallel syntheses of various free fatty acids with 2-amino-2, 2-dimethyl-1-propanol resulted with excellent yields.

  9. A comparative study of the complexation of uranium(VI) withoxydiacetic acid and its amide derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Linfeng; Tian, Guoxin

    2005-05-01

    There has been significant interest in recent years in the studies of alkyl-substituted amides as extractants for actinide separation because the products of radiolytic and hydrolytic degradation of amides are less detrimental to separation processes than those of organophosphorus compounds traditionally used in actinide separations. Stripping of actinides from the amide-containing organic solvents is relatively easy. In addition, the amide ligands are completely incinerable so that the amount of secondary wastes generated in nuclear waste treatment could be significantly reduced. One group of alkyl-substituted oxa-diamides have been shown to be promising in the separation of actinides from nuclear wastes. For example, tetraoctyl-3-oxa-glutaramide and tetraisobutyl-oxa-glutaramide form actinide complexes that can be effectively extracted from nitric acid solutions. To understand the thermodynamic principles governing the complexation of actinides with oxa-diamides, we have studied the complexation of U(VI) with dimethyl-3-oxa-glutaramic acid (DMOGA) and tetramethyl-3-oxa-glutaramide (TMOGA) in aqueous solutions, in comparison with oxydiacetic acid (ODA) (Figure 1). Previous studies have indicated that the complexation of U(VI) with ODA is strong and entropy-driven. Comparing the results for DMOGA and TMOGA with those for ODA could provide insight into the energetics of amide complexation with U(VI) and the relationship between the thermodynamic properties and the ligand structure.

  10. A remarkable activity of human leukotriene A4 hydrolase (LTA4H) toward unnatural amino acids.

    Science.gov (United States)

    Byzia, Anna; Haeggström, Jesper Z; Salvesen, Guy S; Drag, Marcin

    2014-05-01

    Leukotriene A4 hydrolase (LTA4H--EC 3.3.2.6) is a bifunctional zinc metalloenzyme, which processes LTA4 through an epoxide hydrolase activity and is also able to trim one amino acid at a time from N-terminal peptidic substrates via its aminopeptidase activity. In this report, we have utilized a library of 130 individual proteinogenic and unnatural amino acid fluorogenic substrates to determine the aminopeptidase specificity of this enzyme. We have found that the best proteinogenic amino acid recognized by LTA4H is arginine. However, we have also observed several unnatural amino acids, which were significantly better in terms of cleavage rate (k cat/K m values). Among them, the benzyl ester of aspartic acid exhibited a k cat/K m value that was more than two orders of magnitude higher (1.75 × 10(5) M(-1) s(-1)) as compared to L-Arg (1.5 × 10(3) M(-1) s(-1)). This information can be used for design of potent inhibitors of this enzyme, but may also suggest yet undiscovered functions or specificities of LTA4H.

  11. Chemistry around imidazopyrazine and ibuprofen: discovery of novel fatty acid amide hydrolase (FAAH) inhibitors.

    Science.gov (United States)

    De Wael, Frédéric; Muccioli, Giulio G; Lambert, Didier M; Sergent, Thérèse; Schneider, Yves-Jacques; Rees, Jean-François; Marchand-Brynaert, Jacqueline

    2010-09-01

    Based on the imidazo-[1,2-a]-pyrazin-3-(7H)-one scaffold, a dual action prodrug has been designed for combining antioxidant and anti-inflammatory activities, possibly unmasked upon oxidation. The construction of the target-molecule requires two building blocks, namely a 2-amino-1,4-pyrazine and a 2-ketoaldehyde. Attempts to synthesize the 2-ketoaldehyde (5a) derived from ibuprofen failed, but led to the corresponding 2-ketoaldoxime (7a) which could not be condensed with the pyrazine synthons. However, a model compound, i.e. phenylglyoxal aldoxime, reacted well under microwave activation to furnish novel imidazo[1,2-a]-pyrazine-3-(7H)-imine derivatives (18a,b). These heterobicycles behave as antioxidants by inhibiting the lipid peroxidation, and one compound (18b) is endowed with a significant anti-inflammatory effect in a cellular test. Unexpectedly, all the synthetic intermediates derived from ibuprofen are good inhibitors of FAAH, the most active compound (4a) featuring the 1,3-dithian-2-yl motif.

  12. Quantification of primary fatty acid amides in commercial tallow and tallow fatty acid methyl esters by HPLC-APCI-MS.

    Science.gov (United States)

    Madl, Tobias; Mittelbach, Martin

    2005-04-01

    Primary fatty acid amides are a group of biologically highly active compounds which were already identified in nature. Here, these substances were determined in tallow and tallow fatty acid methyl esters for the first time. As tallow is growing in importance as an oleochemical feedstock for the soap manufacturing, the surfactant as well as the biodiesel industry, the amounts of primary fatty acid amides have to be considered. As these compounds are insoluble in tallow as well as in the corresponding product e.g. tallow fatty acid methyl esters, filter plugging can occur. For the quantification in these matrices a purification step and a LC-APCI-MS method were developed. Although quantification of these compounds can be performed by GC-MS, the presented approach omitted any derivatization and increased the sensitivity by two orders of magnitude. Internal standard calibration using heptadecanoic acid amide and validation of the method yielded a limit of detection of 18.5 fmol and recoveries for the tallow and fatty acid methyl ester matrices of 93% and 95%, respectively. A group of commercially available samples were investigated for their content of fatty acid amides resulting in an amount of up to 0.54%m/m (g per 100 g) in tallow and up to 0.16%m/m (g per 100 g) in fatty acid methyl esters.

  13. Biocatalytic Synthesis of Highly Enantiopure 1,4-Benzodioxane-2-carboxylic Acid and Amide

    Institute of Scientific and Technical Information of China (English)

    LIU Jun; WANG De-Xian; ZHENG Qi-Yu; WANG Mei-Xiang

    2006-01-01

    Catalyzed by Rhodococcus erythropolis A J270, a nitrile hydratase and amidase containing microbial whole-cell catalyst, at 10 ℃ and with the use of methanol as a co-solvent, nitrile and amide biotransformations produce 2S-1,4-benzodioxane-2-carboxamide and 2R-1,4-benzodioxane-2-carboxylic acid in high yields with excellent enantioselectivity.

  14. Gene overexpression and biochemical characterization of the biotechnologically relevant chlorogenic acid hydrolase from Aspergillus niger.

    Science.gov (United States)

    Benoit, Isabelle; Asther, Michèle; Bourne, Yves; Navarro, David; Canaan, Stéphane; Lesage-Meessen, Laurence; Herweijer, Marga; Coutinho, Pedro M; Asther, Marcel; Record, Eric

    2007-09-01

    The full-length gene that encodes the chlorogenic acid hydrolase from Aspergillus niger CIRM BRFM 131 was cloned by PCR based on the genome of the strain A. niger CBS 513.88. The complete gene consists of 1,715 bp and codes for a deduced protein of 512 amino acids with a molecular mass of 55,264 Da and an acidic pI of 4.6. The gene was successfully cloned and overexpressed in A. niger to yield 1.25 g liter(-1), i.e., 330-fold higher than the production of wild-type strain A. niger CIRM BRFM131. The histidine-tagged recombinant ChlE protein was purified to homogeneity via a single chromatography step, and its main biochemical properties were characterized. The molecular size of the protein checked by mass spectroscopy was 74,553 Da, suggesting the presence of glycosylation. ChlE is assembled in a tetrameric form with several acidic isoforms with pIs of around 4.55 and 5.2. Other characteristics, such as optimal pH and temperature, were found to be similar to those determined for the previously characterized chlorogenic acid hydrolase of A. niger CIRM BRFM 131. However, there was a significant temperature stability difference in favor of the recombinant protein. ChlE exhibits a catalytic efficiency of 12.5 x 10(6) M(-1) s(-1) toward chlorogenic acid (CGA), and its ability to release caffeic acid from CGA present in agricultural by-products such as apple marc and coffee pulp was clearly demonstrated, confirming the high potential of this enzyme.

  15. Synthesis of new fatty acids amides from aminolysis of fatty acid methyl esters (FAMEs); Sintese de novas amidas graxas a partir da aminolise de esteres metilicos

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Carolina R.; Montes D' Oca, Caroline da Ros; Duarte, Rodrigo da C.; Kurz, Marcia H.S.; Primel, Ednei G.; Clementin, Rosilene M.; Villarreyes, Joaquin Ariel M.; Montes D' Oca, Marcelo G., E-mail: dqmdoca@furg.b [Universidade Federal do Rio Grande, RS (Brazil). Escola de Quimica e Alimentos

    2010-07-01

    Recent biochemical and pharmacological studies have led to the characterization of different fatty acid amides as a new family of biologically active lipids. Here, we describe the synthesis of new amides from C16:0, 18:0, 18:1 and 18:1, OH fatty acids (FFA) families with cyclic and acyclic amines and demonstrate for the first time that these compounds produce cytotoxic effects. Application of this method to the synthesis of fatty acid amides was performed using the esters aminolysis as a key step and various carboxylic amides were prepared in good yield from fatty acid methyl esters (FAMEs). (author)

  16. Oxalic acid production by citric acid-producing Aspergillus niger overexpressing the oxaloacetate hydrolase gene oahA.

    Science.gov (United States)

    Kobayashi, Keiichi; Hattori, Takasumi; Honda, Yuki; Kirimura, Kohtaro

    2014-05-01

    The filamentous fungus Aspergillus niger is used worldwide in the industrial production of citric acid. However, under specific cultivation conditions, citric acid-producing strains of A. niger accumulate oxalic acid as a by-product. Oxalic acid is used as a chelator, detergent, or tanning agent. Here, we sought to develop oxalic acid hyperproducers using A. niger as a host. To generate oxalic acid hyperproducers by metabolic engineering, transformants overexpressing the oahA gene, encoding oxaloacetate hydrolase (OAH; EC 3.7.1.1), were constructed in citric acid-producing A. niger WU-2223L as a host. The oxalic acid production capacity of this strain was examined by cultivation of EOAH-1 under conditions appropriate for oxalic acid production with 30 g/l glucose as a carbon source. Under all the cultivation conditions tested, the amount of oxalic acid produced by EOAH-1, a representative oahA-overexpressing transformant, exceeded that produced by A. niger WU-2223L. A. niger WU-2223L and EOAH-1 produced 15.6 and 28.9 g/l oxalic acid, respectively, during the 12-day cultivation period. The yield of oxalic acid for EOAH-1 was 64.2 % of the maximum theoretical yield. Our method for oxalic acid production gave the highest yield of any study reported to date. Therefore, we succeeded in generating oxalic acid hyperproducers by overexpressing a single gene, i.e., oahA, in citric acid-producing A. niger as a host.

  17. Localization of acid hydrolases in protoplasts. Examination of the proposed lysosomal function of the mature vacuole

    Energy Technology Data Exchange (ETDEWEB)

    Butcher, H.C.; Wagner, G.J.; Siegelman, H.W.

    1977-06-01

    The development of techniques to isolate and purify relatively large quantities of intact vacuoles from mature tissues permits direct biochemical analysis of this ubiquitous mature plant cell organelle. Vacuoles and a fraction enriched in soluble cytoplasmic constituents were quantitatively prepared from Hippeastrum flower petal protoplasts. Vacuolar lysate and soluble cytoplasmic fractions were examined for acid hydrolase activities commonly associated with animal lysosomes, and pH optima were determined. Esterase, protease, carboxypeptidase, ..beta..-galactosidase, ..cap alpha..-glycosidase and ..beta..-glycosidase, not found in the vacuole lysate fraction, were components of the soluble cytoplasmic fraction. Acid phosphatase, RNase and DNase were present in both fractions. Vacuolar enzyme activities were also examined as a function of flower development from bud through senescent stages. The data obtained are not consistent with the concept that the mature plant cell vacuole functions as a generalized lysosome.

  18. Physiological and biochemical studies of bacterial amino acid amide metabolism

    NARCIS (Netherlands)

    Hermes, Hubertus Franciscus Maria

    2008-01-01

    Amino acids represent a class of versatile chiral building blocks for a whole range of fine chemicals, used in the pharmaceutical and agro-chemical industry. Considerable experience currently is available with a wide variety of chemo-enzymatic processes for the synthesis of amino acids, which is app

  19. End-Crosslinking Gelation of Poly(amide acid) Gels studied with Scanning Microscopic Light Scattering

    OpenAIRE

    Furukawa, Hidemitsu; Kobayashi, Mizuha; Miyashita, Yoshiharu; HORIE, Kazuyuki

    2006-01-01

    Network formation in the gelation process of end-crosslinked poly(amide acid) gels, which are the precursor of end-crosslinked polyimide gels, was studied by scanning dynamic light scattering. The gelation process is essentially non-reversible due to the formation of covalent bonds. The molecular structure formed in the gelation process is controlled by varying the equivalence ratio of end-crosslinker to oligomer during the preparation. It was found that a couple of relaxation modes are obser...

  20. Chiral amide from (1, 2)-(+)-norephedrine and furoic acid: An efficient catalyst for asymmetric Reformatsky reaction

    Indian Academy of Sciences (India)

    Nallamuthu Ananthi; Sivan Velmathi

    2014-01-01

    Chiral amide derived from (1, 2)-(+)-norephedrine and 2-furoic acid was found to catalyse the asymmetric Reformatsky reaction between prochiral aldehydes and α-bromo ethylacetate with diethylzinc as zinc source. The corresponding chiral -hydroxy esters were formed in 99% yield with over 80% enantiomeric excess. The presence of air was found to be essential for the effective C-C bond formation. The mechanism for the catalytic reaction was proposed.

  1. Synthesis and Properties of Lactic Acid-based Cross-linked Poly(ester-amide)

    Institute of Scientific and Technical Information of China (English)

    Yue Ying HE; Cong Ming XIAO

    2006-01-01

    A novel lactic acid-based cross-linked poly(ester-amide) (LCPEA) was synthesized. The gel fraction of the LCPEA could be modulated by the reaction conditions and it affected the mechanical and thermal properties of the LCPEA. The tensile strength, elastic modulus and bend strength of the LCPEA of 65% gel fraction were 4.65, 136.55 and 39.63 MPa, respectively. The thermal decomposition temperature (50 wt%) of the LCPEA was around 410 ℃.

  2. Partial purification and characterization of an inducible indole-3-acetyl-L-aspartic acid hydrolase from Enterobacter agglomerans

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Jyh-Ching [Department of Agriculture, Beltsville, MD (United States)]|[Univ. of Maryland, College Park, MD (United States); Cohen, J.D.; Mulbry, W.W. [Department of Agriculture, Beltsville, MD (United States)] [and others

    1996-11-01

    Indole-3-acetyl-amino acid conjugate hydrolases are believed to be important in the regulation of indole-3-acetic acid (IAA) metabolism in plants and therefore have potential uses for the alteration of plant IAA metabolism. To isolate bacterial strains exhibiting significant indole-3-acetyl-aspartate (IAA-Asp) hydrolase activity, a sewage sludge inoculation was cultured under conditions in which IAA-Asp served as the sole source of carbon and nitrogen. One isolate, Enterobacter agglomerans, showed hydrolase activity inducible by IAA-L-Asp or N-acetyl-L-Asp but not by IAA, (NH{sub 4}){sub 2}SO{sub 4}, urea, or indoleacetamide. Among a total of 17 IAA conjugates tested as potential substrates, the enzyme had an exclusively high substrate specificity for IAA-L-Asp of 13.5 mM. The optimal pH for this enzyme was between 8.0 and 8.5. In extraction buffer containing 0.8 mM Mg{sup 2+} the hydrolase activity was inhibited to 80% by 1 mM dithiothreitol and to 60% by 1 mm CuSO{sub 4}; the activity was increased by 40% with 1mM MnSO{sub 4}. However, in extraction buffer with no trace elements, the hydrolase activity was inhibited to 50% by either 1 mM dithiothreitol or 1% Triton X-100 (Sigma). These results suggest that disulfide bonding might be essential for enzyme activity. Purification of the hydrolase by hydroxyapatite and TSK-phenyl (HP-Genenchem, South San Francisco, CA) preparative high-performance liquid chromatography yielded a major 45-kD polypeptide as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 45 refs., 5 figs., 3 tabs.

  3. Sulfonated reduced graphene oxide as a highly efficient catalyst for direct amidation of carboxylic acids with amines using ultrasonic irradiation.

    Science.gov (United States)

    Mirza-Aghayan, Maryam; Tavana, Mahdieh Molaee; Boukherroub, Rabah

    2016-03-01

    Sulfonated reduced graphene oxide nanosheets (rGO-SO3H) were prepared by grafting sulfonic acid-containing aryl radicals onto chemically reduced graphene oxide (rGO) under sonochemical conditions. rGO-SO3H catalyst was characterized by Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). rGO-SO3H catalyst was successfully applied as a reusable solid acid catalyst for the direct amidation of carboxylic acids with amines into the corresponding amides under ultrasonic irradiation. The direct sonochemical amidation of carboxylic acid takes place under mild conditions affording in good to high yields (56-95%) the corresponding amides in short reaction times.

  4. Design, synthesis, and evaluation of caffeic acid amides as synergists to sensitize fluconazole-resistant Candida albicans to fluconazole.

    Science.gov (United States)

    Dai, Li; Zang, Chengxu; Tian, Shujuan; Liu, Wei; Tan, Shanlun; Cai, Zhan; Ni, Tingjunhong; An, Maomao; Li, Ran; Gao, Yue; Zhang, Dazhi; Jiang, Yuanying

    2015-01-01

    A series of caffeic acid amides were designed, synthesized, and their synergistic activity with fluconazole against fluconazole-resistant Candida albicans was evaluated in vitro. The title caffeic acid amides 3-30 except 26 exhibited potent activity, and the subsequent SAR study was conducted. Compound 3, 5, 21, and 34c, at a concentration of 1.0 μg/ml, decreased the MIC₈₀ of fluconazole from 128.0 μg/ml to 1.0-0.5 μg/ml against the fluconazole-resistant C. albicans. This result suggests that the caffeic acid amides, as synergists, can sensitize drug-resistant fungi to fluconazole. The SAR study indicated that the dihydroxyl groups and the amido groups linking to phenyl or heterocyclic rings are the important pharmacophores of the caffeic acid amides.

  5. Neuronal transport of acid hydrolases and peroxidase within the lysosomal system or organelles: involvement of agranular reticulum-like cisterns.

    Science.gov (United States)

    Broadwell, R D; Oliver, C; Brightman, M W

    1980-04-01

    Neurosecretory neurons of the hyperosmotically stressed hypothalamo-neurohypophysial system have been a useful model with which to demonstrate interrelationships among perikaryal lysosomes, agranular reticulum-like cisterns, endocytotic vacuoles, and the axoplasmic transport of acid hydrolases and horseradish peroxidase. Supraoptic neurons from normal mice and mice given 2% salt water to drink for 5--8 days have been studied using enzyme cytochemical techniques for peroxidase and lysosomal acid hydrolases. Peroxidase-labeling of these neurons was accomplished by intravenous injection or cerebral ventriculocisternal perfusion of the protein as previously reported (Broadwell and Brightman, '79). Compared to normal controls, supraoptic cell bodies from hyperosmotically stimulated mice contained elevated concentrations of peroxidase-labeled dense bodies demonstrated to be secondary lysosomes and acid hydrolase-positive and peroxidase-positive cisterns either attached or unattached to secondary lysosomes. These cisterns were smooth-surfaced and 400--1,000 A wide. Their morphology was similar to that of the agranular reticulum. Some of the cisterns contained both peroxidase and acid hydrolase activities. The cisterns probably represent an elongated form of lysosome and, therefore, are not elements of the agranular reticulum per se. By virtue of their direct connections with perikaryal secondary lysosomes, these cisterns may provide the route by which acid hydrolases and exogenous macromolecules can leave perikaryal secondary lysosomes for anterograde flow down the axon. Very few smooth-surfaced cisterns were involved in the retrograde transport of peroxidase within pituitary stalk axons from normal and salt-treated mice injected intravenously with peroxidase. Peroxidase undergoing retrograde transport was predominantly in endocytotic structures such as vacuoles and cup-shaped organelles, which deliver this exogenous macromolecule directly to secondary lysosomes for

  6. Temperature dependence of amino acid side chain IR absorptions in the amide I' region.

    Science.gov (United States)

    Anderson, Benjamin A; Literati, Alex; Ball, Borden; Kubelka, Jan

    2014-05-01

    Amide I' IR spectra are widely used for studies of structural changes in peptides and proteins as a function of temperature. Temperature dependent absorptions of amino acid side-chains that overlap the amide I' may significantly complicate the structural analyses. While the side-chain IR spectra have been investigated previously, thus far their dependence on temperature has not been reported. Here we present the study of the changes in the IR spectra with temperature for side-chain groups of aspartate, glutamate, asparagine, glutamine, arginine, and tyrosine in the amide I' region (in D2O). Band fitting analysis was employed to extract the temperature dependence of the individual spectral parameters, such as peak frequency, integrated intensity, band width, and shape. As expected, the side-chain IR bands exhibit significant changes with temperature. The majority of the spectral parameters, particularly the frequency and intensity, show linear dependence on temperature, but the direction and magnitude vary depending on the particular side-chain group. The exception is arginine, which exhibits a distinctly nonlinear frequency shift with temperature for its asymmetric CN3H5(+) bending signal, although a linear fit can account for this change to within ~1/3 cm(-1). The applicability of the determined spectral parameters for estimations of temperature-dependent side-chain absorptions in peptides and proteins are discussed.

  7. Revised molecular basis of the promiscuous carboxylic acid perhydrolase activity in serine hydrolases.

    Science.gov (United States)

    Yin, DeLu Tyler; Kazlauskas, Romas J

    2012-06-25

    Several serine hydrolases catalyze a promiscuous reaction: perhydrolysis of carboxylic acids to form peroxycarboxylic acids. The working hypothesis is that perhydrolases are more selective than esterases for hydrogen peroxide over water. In this study, we tested this hypothesis, and focused on L29P-PFE (Pseudomonas fluorescens esterase), which catalyzes perhydrolysis of acetic acid 43-fold faster than wild-type PFE. This hypothesis predicts that L29P-PFE should be approximately 43-fold more selective for hydrogen peroxide than wild-type PFE, but experiments show that L29P-PFE is less selective. The ratio of hydrolysis to perhydrolysis of methyl acetate at different concentrations of hydrogen peroxide fit a kinetic model for nucleophile selectivity. L29P-PFE (β(0)=170  M(-1)) is approximately half as selective for hydrogen peroxide over water than wild-type PFE (β(0)=330  M(-1)), which contradicts the working hypothesis. An alternative hypothesis is that carboxylic acid perhydrolases increase perhydrolysis by forming the acyl-enzyme intermediate faster. Consistent with this hypothesis, the rate of acetyl-enzyme formation, measured by (18)O-water exchange into acetic acid, was 25-fold faster with L29P-PFE than with wild-type PFE, which is similar to the 43-fold faster perhydrolysis with L29P-PFE. Molecular modeling of the first tetrahedral intermediate (T(d)1) suggests that a closer carbonyl group found in perhydrolases accepts a hydrogen bond from the leaving group water. This revised understanding can help design more efficient enzymes for perhydrolysis and shows how subtle changes can create new, unnatural functions in enzymes.

  8. Synthesis, Anti-HCV, Antioxidant and Reduction of Intracellular Reactive Oxygen Species Generation of a Chlorogenic Acid Analogue with an Amide Bond Replacing the Ester Bond

    Directory of Open Access Journals (Sweden)

    Ling-Na Wang

    2016-06-01

    Full Text Available Chlorogenic acid is a well known natural product with important bioactivities. It contains an ester bond formed between the COOH of caffeic acid and the 3-OH of quinic acid. We synthesized a chlorogenic acid analogue, 3α-caffeoylquinic acid amide, using caffeic and quinic acids as starting materials. The caffeoylquinc acid amide was found to be much more stable than chlorogenic acid and showed anti-Hepatitis C virus (anti-HCV activity with a potency similar to chlorogenic acid. The caffeoylquinc acid amide potently protected HepG2 cells against oxidative stress induced by tert-butyl hydroperoxide.

  9. SYNTHESIS AND CHARACTERIZATION OF HYPERBRANCHED POLY(ESTER-AMIDE)S BASED ON GALLIC ACID AND DL-2-AMINOBUTYRIC ACID

    Institute of Scientific and Technical Information of China (English)

    Ya-li Su; Xiu-ru Li; Yue-jin Tong; Yue-sheng Li

    2004-01-01

    A novel AB3-type monomer was prepared from gallic acid and DL-2-aminobutyric acid, and used for the synthesis of the biocompatible hyperbranched poly(ester-amide)s by self-polycondensation. The polymers were characterized via FTIR and NMR spectroscopy and thermal analysis, and the average degree of branching of the polymers was estimated to be 0.75.The polymers with abundant acetyl end groups were found to be amorphous with lower intrinsic viscosity, better thermal stability and excellent solubility.

  10. An Investigation of Solid-State Amidization and Imidization Reactions in Vapor Deposited Poly (amic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Anthamatten, M; Letts, S A; Day, K; Cook, R C; Gies, A P; Hamilton, T P; Nonidez, W K

    2004-06-28

    The condensation polymerization reaction of 4,4'-oxydianiline (ODA) with pyromellitic dianhydride (PMDA) to form poly(amic acid) and the subsequent imidization reaction to form polyimide were investigated for films prepared using vapor deposition polymerization techniques. Fourier-transform infrared spectroscopy (FT-IR), thermal analysis, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) of films at different temperatures indicate that additional solid-state polymerization occurs prior to imidization reactions. Experiments reveal that, upon vapor deposition, poly(amic acid) oligomers form that have a number-average molecular weight of about 1500 Daltons. Between 100 - 130 C these chains undergo additional condensation reaction to form slightly higher molecular weight oligomers. Calorimetry measurements show that this reaction is exothermic ({Delta}H {approx} -30 J/g) with an activation energy of about 120 kJ/mol. Experimental reaction enthalpies are compared to results from ab initio molecular modeling calculations to estimate the number of amide groups formed. At higher temperatures (150 - 300 C) imidization of amide linkages occurs as an endothermic reaction ({Delta}H {approx} +120 J/g) with an activation energy of about 130 kJ/mol. Solid-state kinetics were found to depend on reaction conversion as well as the processing conditions used to deposit films.

  11. Cinnamic acid amides from Tribulus terrestris displaying uncompetitive α-glucosidase inhibition.

    Science.gov (United States)

    Song, Yeong Hun; Kim, Dae Wook; Curtis-Long, Marcus J; Park, Chanin; Son, Minky; Kim, Jeong Yoon; Yuk, Heung Joo; Lee, Keun Woo; Park, Ki Hun

    2016-05-23

    The α-glucosidase inhibitory potential of Tribulus terrestris extracts has been reported but as yet the active ingredients are unknown. This study attempted to isolate the responsible metabolites and elucidate their inhibition mechanism of α-glucosidase. By fractionating T. terristris extracts, three cinnamic acid amide derivatives (1-3) were ascertained to be active components against α-glucosidase. The lead structure, N-trans-coumaroyltyramine 1, showed significant inhibition of α-glucosidase (IC50 = 0.42 μM). Moreover, all active compounds displayed uncompetitive inhibition mechanisms that have rarely been reported for α-glucosidase inhibitors. This kinetic behavior was fully demonstrated by showing a decrease of both Km and Vmax, and Kik/Kiv ratio ranging between 1.029 and 1.053. We progressed to study how chemical modifications to the lead structure 1 may impact inhibition. An α, β-unsaturation carbonyl group and hydroxyl group in A-ring of cinnamic acid amide emerged to be critical functionalities for α-glucosidase inhibition. The molecular modeling study revealed that the inhibitory activities are tightly related to π-π interaction as well as hydrogen bond interaction between enzyme and inhibitors.

  12. The effect of pH on the toxicity of fatty acids and fatty acid amides to rainbow trout gill cells.

    Science.gov (United States)

    Bertin, Matthew J; Voronca, Delia C; Chapman, Robert W; Moeller, Peter D R

    2014-01-01

    Harmful algal blooms (HABs) expose aquatic organisms to multiple physical and chemical stressors during an acute time period. Algal toxins themselves may be altered by water chemistry parameters affecting their bioavailability and resultant toxicity. The purpose of this study was to determine the effects of two abiotic parameters (pH, inorganic metal salts) on the toxicity of fatty acid amides and fatty acids, two classes of lipids produced by harmful algae, including the golden alga, Prymnesium parvum, that are toxic to aquatic organisms. Rainbow trout gill cells were used as a model of the fish gill and exposed to single compounds and mixtures of compounds along with variations in pH level and concentration of inorganic metal salts. We employed artificial neural networks (ANNs) and standard ANOVA statistical analysis to examine and predict the effects of these abiotic parameters on the toxicity of fatty acid amides and fatty acids. Our results demonstrate that increasing pH levels increases the toxicity of fatty acid amides and inhibits the toxicity of fatty acids. This phenomenon is reversed at lower pH levels. Exposing gill cells to complex mixtures of chemical factors resulted in dramatic increases in toxicity compared to tests of single compounds for both the fatty acid amides and fatty acids. These findings highlight the potential of physicochemical factors to affect the toxicity of chemicals released during algal blooms and demonstrate drastic differences in the effect of pH on fatty acid amides and fatty acids.

  13. Improved annotation of conjugated bile acid hydrolase superfamily members in Gram-positive bacteria.

    NARCIS (Netherlands)

    Lambert, J.M.; Siezen, R.J.; Vos, W.M. de; Kleerebezem, M.

    2008-01-01

    Most Gram-positive bacteria inhabiting the gastrointestinal tract are capable of hydrolysing bile salts. Bile salt hydrolysis is thought to play an important role in various biological processes in the host. Therefore, correct annotation of bacterial bile salt hydrolases (Bsh) in public databases (E

  14. Improved annotation of conjugated bile acid hydrolase superfamily members in Gram-positive bacteria

    NARCIS (Netherlands)

    Lambert, J.M.; Siezen, R.J.; Vos, de W.M.; Kleerebezem, M.

    2008-01-01

    Most Gram-positive bacteria inhabiting the gastrointestinal tract are capable of hydrolysing bile salts. Bile salt hydrolysis is thought to play an important role in various biological processes in the host. Therefore, correct annotation of bacterial bile salt hydrolases (Bsh) in public databases (E

  15. GC AND LC CHROMATOGRAPHIC AND EI, CE, +/- CI, AND ES MASS SPECTRAL CHARACTERISTICS OF SALTS AND AMIDES OF PERFLUOROOCTANESULFONIC ACID

    Science.gov (United States)

    In 1976, fluorine in human blood serum was thought to be present as perfluorooctanic acid; however, in the 1990s it was correctly identified by LC/MS as perfluorooctanesulfonate (PFOS). PFOS was both a commercial product and an end-stage metabolite of numerous substituted amides ...

  16. Structure-activity relationships of fatty acid amide ligands in activating and desensitizing G protein-coupled receptor 119.

    Science.gov (United States)

    Kumar, Pritesh; Kumar, Akhilesh; Song, Zhao-Hui

    2014-01-15

    The purpose of the current study was to apply a high throughput assay to investigate the structure-activity relationships of fatty acid amides for activating and desensitizing G protein-coupled receptor 119, a promising therapeutic target for both type 2 diabetes and obesity. A cell-based, homogenous time resolved fluorescence (HTRF) method for measuring G protein-coupled receptor 119-mediated increase of cyclic adenosine monophosphate (cAMP) levels was validated and applied in this study. Using novel fatty acid amides and detailed potency and efficacy analyses, we have demonstrated that degree of saturation in acyl chain and charged head groups of fatty acid amides have profound effects on the ability of these compounds to activate G protein-coupled receptor 119. In addition, we have demonstrated for the first time that pretreatments with G protein-coupled receptor 119 agonists desensitize the receptor and the degrees of desensitization caused by fatty acid amides correlate well with their structure-activity relationships in activating the receptor.

  17. [Bis(2-methoxyethyl)amino]sulfur trifluoride, the Deoxo-Fluor reagent: application toward one-flask transformations of carboxylic acids to amides.

    Science.gov (United States)

    White, Jonathan M; Tunoori, Ashok Rao; Turunen, Brandon J; Georg, Gunda I

    2004-04-02

    The use of the Deoxo-Fluor reagent is a versatile method for acyl fluoride generation and subsequent one-flask amide coupling. It provides mild conditions and facile purification of the desired products in good to excellent yields. We have explored the utility of this reagent for the one-flask conversion of acids to amides and Weinreb amides and as a peptide-coupling reagent.

  18. Evaluation of physicochemical properties, skin permeation and accumulation profiles of salicylic acid amide prodrugs as sunscreen agent.

    Science.gov (United States)

    Yan, Yi-Dong; Sung, Jun Ho; Lee, Dong Won; Kim, Jung Sun; Jeon, Eun-Mi; Kim, Dae-Duk; Kim, Dong Wuk; Kim, Jong Oh; Piao, Ming Guan; Li, Dong Xun; Yong, Chul Soon; Choi, Han Gon

    2011-10-31

    Various amide prodrugs of salicylic acid were synthesised, and their physicochemical properties including lipophilicity, chemical stability and enzymatic hydrolysis were investigated. In vivo skin permeation and accumulation profiles were also evaluated using a combination of common permeation enhancing techniques such as the use of a supersaturated solution of permeants in an enhancer vehicle, a lipophilic receptor solution, removal of the stratum corneum and delipidisation of skin. Their capacity factor values were proportional to the degree of carbon-carbon saturation in the side chain. All these amides were highly stable in acetonitrile and glycerine. Amide prodrugs were converted to salicylic acid both in hairless mouse liver and skin homogenates. N-dodecyl salicylamide (C12SM) showed the lowest permeation of salicylic acid in skin compared to the other prodrugs, probably due to its low aqueous solubility. It had a high affinity for the stratum corneum and its accumulation was restricted to only the uppermost layer of skin. Thus, this amide prodrug could be a safer topical sunscreen agent with minimum potential for systemic absorption.

  19. Genetic engineering activates biosynthesis of aromatic fumaric acid amides in the human pathogen Aspergillus fumigatus.

    Science.gov (United States)

    Kalb, Daniel; Heinekamp, Thorsten; Lackner, Gerald; Scharf, Daniel H; Dahse, Hans-Martin; Brakhage, Axel A; Hoffmeister, Dirk

    2015-03-01

    The Aspergillus fumigatus nonribosomal peptide synthetase FtpA is among the few of this species whose natural product has remained unknown. Both FtpA adenylation domains were characterized in vitro. Fumaric acid was identified as preferred substrate of the first and both l-tyrosine and l-phenylalanine as preferred substrates of the second adenylation domain. Genetically engineered A. fumigatus strains expressed either ftpA or the regulator gene ftpR, encoded in the same cluster of genes, under the control of the doxycycline-inducible tetracycline-induced transcriptional activation (tet-on) cassette. These strains produced fumaryl-l-tyrosine and fumaryl-l-phenylalanine which were identified by liquid chromatography and high-resolution mass spectrometry. Modeling of the first adenylation domain in silico provided insight into the structural requirements to bind fumaric acid as peptide synthetase substrate. This work adds aromatic fumaric acid amides to the secondary metabolome of the important human pathogen A. fumigatus which was previously not known as a producer of these compounds.

  20. Versatile Biodegradable Poly(ester amides Derived from α-Amino Acids for Vascular Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Pooneh Karimi

    2010-03-01

    Full Text Available Biodegradable poly(ester amide (PEA biomaterials derived from α-amino acids, diols, and diacids are promising materials for biomedical applications such as tissue engineering and drug delivery because of their optimized properties and susceptibility for either hydrolytic or enzymatic degradation. The objective of this work was to synthesize and characterize biodegradable PEAs based on the α-amino acids L-phenylalanine and L-methionine. Four different PEAs were prepared using 1,4-butanediol, 1,6-hexanediol, and sebacic acid by interfacial polymerization. High molecular weight PEAs with narrow polydispersity indices and excellent film-forming properties were obtained. The incubation of these PEAs in PBS and chymotrypsin indicated that the polymers are biodegradable. Human coronary artery smooth muscle cells were cultured on PEA films for 48 h and the results showed a well-spread morphology. Porous 3D scaffolds fabricated from these PEAs were found to have excellent porosities indicating the utility of these polymers for vascular tissue engineering.

  1. Cu(I)-catalyzed (11)C carboxylation of boronic acid esters: a rapid and convenient entry to (11)C-labeled carboxylic acids, esters, and amides.

    Science.gov (United States)

    Riss, Patrick J; Lu, Shuiyu; Telu, Sanjay; Aigbirhio, Franklin I; Pike, Victor W

    2012-03-12

    Rapid and direct: the carboxylation of boronic acid esters with (11)CO(2) provides [(11)C]carboxylic acids as a convenient entry into [(11)C]esters and [(11)C]amides. This conversion of boronates is tolerant to diverse functional groups (e.g., halo, nitro, or carbonyl).

  2. Preventive effect of phytic acid on lysosomal hydrolases in normal and isoproterenol-induced myocardial infarction in Wistar rats.

    Science.gov (United States)

    Brindha, E; Rajasekapandiyan, M

    2015-02-01

    This study was aimed to evaluate the preventive role of phytic acid on lysosomal enzymes in isoproterenol (ISO)-induced myocardial infarction (MI) in male Wistar rats. Rats subcutaneously injected with ISO (85 mg/kg) at an interval of 24 h for two days showed a significant increase in the activities of lysosomal enzymes (glucuronidase, N-acetyl glucosaminidase, galactosidase, cathepsin-B and cathepsin-D) were increased significantly in serum and the heart of ISO-induced rats, but the activities of glucuronidase and cathepsin-D were decreased significantly in the lysosomal fraction of the heart. Pretreatment with phytic acid (25 and 50 mg/kg) daily for a period of 56 d positively altered activities of lysosomal hydrolases in ISO-induced rats. Thus, phytic acid possesses a cardioprotective effect in ISO-induced MI in rats.

  3. Involvement of a Natural Fusion of a Cytochrome P450 and a Hydrolase in Mycophenolic Acid Biosynthesis

    DEFF Research Database (Denmark)

    Hansen, Bjarne Gram; Mnich, Ewelina; Nielsen, Kristian Fog;

    2012-01-01

    C, a polyketide synthase producing 5-methylorsellinic acid (5-MOA). However, the biochemical role of the enzymes encoded by the remaining genes in the MPA gene cluster is still unknown. Based on bioinformatic analysis of the MPA gene cluster, we hypothesized that the step following 5-MOA production in the pathway......Mycophenolic acid (MPA) is a fungal secondary metabolite and the active component in several immunosuppressive pharmaceuticals. The gene cluster coding for the MPA biosynthetic pathway has recently been discovered in Penicillium brevicompactum, demonstrating that the first step is catalyzed by Mpa...... that the P450 catalyzes hydroxylation of 5-MOA to 4,6-dihydroxy-2-(hydroxymethyl)-3-methylbenzoic acid (DHMB). DHMB is then converted to DHMP, and our results suggest that the hydrolase domain aids this second step by acting as a lactone synthase that catalyzes the ring closure. Overall, the chimeric enzyme...

  4. Synthesis and structure-activity relationship of piperidine-derived non-urea soluble epoxide hydrolase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Pecic, Stevan; Pakhomova, Svetlana; Newcomer, Marcia E.; Morisseau, Christophe; Hammock, Bruce D.; Zhu, Zhengxiang; Rinderspacher, Alison; Deng, Shi-Xian [UCD; (LSU); (Columbia)

    2013-09-27

    A series of potent amide non-urea inhibitors of soluble epoxide hydrolase (sEH) is disclosed. The inhibition of soluble epoxide hydrolase leads to elevated levels of epoxyeicosatrienoic acids (EETs), and thus inhibitors of sEH represent one of a novel approach to the development of vasodilatory and anti-inflammatory drugs. Structure–activities studies guided optimization of a lead compound, identified through high-throughput screening, gave rise to sub-nanomolar inhibitors of human sEH with stability in human liver microsomal assay suitable for preclinical development.

  5. Synthesis, Anti-HCV, Antioxidant and Reduction of Intracellular Reactive Oxygen Species Generation of a Chlorogenic Acid Analogue with an Amide Bond Replacing the Ester Bond

    OpenAIRE

    2016-01-01

    Chlorogenic acid is a well known natural product with important bioactivities. It contains an ester bond formed between the COOH of caffeic acid and the 3-OH of quinic acid. We synthesized a chlorogenic acid analogue, 3α-caffeoylquinic acid amide, using caffeic and quinic acids as starting materials. The caffeoylquinc acid amide was found to be much more stable than chlorogenic acid and showed anti-Hepatitis C virus (anti-HCV) activity with a potency similar to chlorogenic acid. The caffeoylq...

  6. Water-stable helical structure of tertiary amides of bicyclic β-amino acid bearing 7-azabicyclo[2.2.1]heptane. Full control of amide cis-trans equilibrium by bridgehead substitution.

    Science.gov (United States)

    Hosoya, Masahiro; Otani, Yuko; Kawahata, Masatoshi; Yamaguchi, Kentaro; Ohwada, Tomohiko

    2010-10-27

    Helical structures of oligomers of non-natural β-amino acids are significantly stabilized by intramolecular hydrogen bonding between main-chain amide moieties in many cases, but the structures are generally susceptible to the environment; that is, helices may unfold in protic solvents such as water. For the generation of non-hydrogen-bonded ordered structures of amides (tertiary amides in most cases), control of cis-trans isomerization is crucial, even though there is only a small sterical difference with respect to cis and trans orientations. We have established methods for synthesis of conformationally constrained β-proline mimics, that is, bridgehead-substituted 7-azabicyclo[2.2.1]heptane-2-endo-carboxylic acids. Our crystallographic, 1D- and 2D-NMR, and CD spectroscopic studies in solution revealed that a bridgehead methoxymethyl substituent completely biased the cis-trans equilibrium to the cis-amide structure along the main chain, and helical structures based on the cis-amide linkage were generated independently of the number of residues, from the minimalist dimer through the tetramer, hexamer, and up to the octamer, and irrespective of the solvent (e.g., water, alcohol, halogenated solvents, and cyclohexane). Generality of the control of the amide equilibrium by bridgehead substitution was also examined.

  7. Characterization of an Indole-3-Acetamide Hydrolase from Alcaligenes faecalis subsp. parafaecalis and Its Application in Efficient Preparation of Both Enantiomers of Chiral Building Block 2,3-Dihydro-1,4-Benzodioxin-2-Carboxylic Acid.

    Directory of Open Access Journals (Sweden)

    Pradeep Mishra

    Full Text Available Both the enantiomers of 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid are valuable chiral synthons for enantiospecific synthesis of therapeutic agents such as (S-doxazosin mesylate, WB 4101, MKC 242, 2,3-dihydro-2-hydroxymethyl-1,4-benzodioxin, and N-[2,4-oxo-1,3-thiazolidin-3-yl]-2,3-dihydro-1,4-benzodioxin-2-carboxamide. Pharmaceutical applications require these enantiomers in optically pure form. However, currently available methods suffer from one drawback or other, such as low efficiency, uncommon and not so easily accessible chiral resolving agent and less than optimal enantiomeric purity. Our interest in finding a biocatalyst for efficient production of enantiomerically pure 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid lead us to discover an amidase activity from Alcaligenes faecalis subsp. parafaecalis, which was able to kinetically resolve 2,3-dihydro-1,4-benzodioxin-2-carboxyamide with E value of >200. Thus, at about 50% conversion, (R-2,3-dihydro-1,4-benzodioxin-2-carboxylic acid was produced in >99% e.e. The remaining amide had (S-configuration and 99% e.e. The amide and acid were easily separated by aqueous (alkaline-organic two phase extraction method. The same amidase was able to catalyse, albeit at much lower rate the hydrolysis of (S-amide to (S-acid without loss of e.e. The amidase activity was identified as indole-3-acetamide hydrolase (IaaH. IaaH is known to catalyse conversion of indole-3-acetamide (IAM to indole-3-acetic acid (IAA, which is phytohormone of auxin class and is widespread among plants and bacteria that inhabit plant rhizosphere. IaaH exhibited high activity for 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which was about 65% compared to its natural substrate, indole-3-acetamide. The natural substrate for IaaH indole-3-acetamide shared, at least in part a similar bicyclic structure with 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which may account for high activity of enzyme towards this un-natural substrate. To

  8. Synthesis of novel nanostructured chiral poly(amide-imide)s containing dopamine and natural amino acids

    Indian Academy of Sciences (India)

    Shadpour Mallakpour; Amin Zadehnazari

    2013-01-01

    Four new thermally stable and optically active poly(amide-imide)s (PAI)s with good inherent viscosities were synthesized from the direct polycondensation reaction of N,N'-(pyromellitoyl)-bis-L--amino acids with 3,5-diamino-N-(3,4-dihydroxy-phen-ethyl)benzamide in a medium consisting of a molten salt, tetrabutylammonium bromide, and triphenyl phosphite as the activator. The polymerization reactions produced a series of novel PAIs containing dopamine segment in the side chain in high yield with inherent viscosities between 0.33 and 0.49 dL/g. The obtained polymers were typically characterized by means of FT-IR, 1HNMR spectroscopy, elemental analyses, powder X-ray diffraction, field emission scanning electronmicroscopy, inherent viscosity, and solubility tests. Thermal properties and flame retardant behaviour of the PAIs were also investigated using thermal gravimetric analysis (TGA and DTG) and limiting oxygen index (LOI). Data obtained by thermal analysis revealed that these polymers showed good thermal stability. Furthermore, high char yield in TGA and good LOI values indicated that the obtained polymers were capable of exhibiting good flame retardant properties.

  9. Identification of the catalytic residues of alpha-amino acid ester hydrolase from Acetobacter turbidans by labeling and site-directed mutagenesis

    NARCIS (Netherlands)

    Polderman - Tijmes, Jolanda j.; Jekel, Peter A.; Jeronimus-Stratingh, CM; Bruins, Andries P.; van der Laan, Jan-Metske; Sonke, Theo; Janssen, Dick B.

    2002-01-01

    The alpha-amino acid ester hydrolase from Acetobacter turbidans ATCC 9325 is capable of hydrolyzing and synthesizing the side chain peptide bond in beta-lactam antibiotics. Data base searches revealed that the enzyme contains an active site serine consensus sequence Gly-X-Ser-Tyr-X-Gly that is also

  10. A comparison of the effects of amide and acid groups at the C-terminus on the collision-induced dissociation of deprotonated peptides.

    Science.gov (United States)

    Bokatzian-Johnson, Samantha S; Stover, Michele L; Dixon, David A; Cassady, Carolyn J

    2012-09-01

    The dissociative behavior of peptide amides and free acids was explored using low-energy collision-induced dissociation and high level computational theory. Both positive and negative ion modes were utilized, but the most profound differences were observed for the deprotonated species. Deprotonated peptide amides produce a characteristic c(m-2)(-) product ion (where m is the number of residues in the peptide) that is either absent or in low abundance in the analogous peptide acid spectrum. Peptide acids show an enhanced formation of c(m-3)(-); however, this is not generally as pronounced as c(m-2)(-) production from amides. The most notable occurrence of an amide-specific product ion is for laminin amide (YIGSR-NH(2)) and this case was investigated using several modified peptides. Mechanisms involving 6- and 9-membered ring formation were proposed, and their energetic properties were investigated using G3(MP2) molecular orbital theory calculations. For example, with C-terminal deprotonation of pentaglycine amide, formation of c(m-2)(-) and a 6-membered ring diketopiperazine neutral requires >31.6 kcal/mol, which is 26.1 kcal/mol less than the analogous process involving the peptide acid. The end group specific fragmentation of peptide amides in the negative ion mode may be useful for identifying such groups in proteomic applications.

  11. A Comparison of the Effects of Amide and Acid Groups at the C-Terminus on the Collision-Induced Dissociation of Deprotonated Peptides

    Science.gov (United States)

    Bokatzian-Johnson, Samantha S.; Stover, Michele L.; Dixon, David A.; Cassady, Carolyn J.

    2012-09-01

    The dissociative behavior of peptide amides and free acids was explored using low-energy collision-induced dissociation and high level computational theory. Both positive and negative ion modes were utilized, but the most profound differences were observed for the deprotonated species. Deprotonated peptide amides produce a characteristic cm-2 - product ion (where m is the number of residues in the peptide) that is either absent or in low abundance in the analogous peptide acid spectrum. Peptide acids show an enhanced formation of cm-3 -; however, this is not generally as pronounced as cm-2 - production from amides. The most notable occurrence of an amide-specific product ion is for laminin amide (YIGSR-NH2) and this case was investigated using several modified peptides. Mechanisms involving 6- and 9-membered ring formation were proposed, and their energetic properties were investigated using G3(MP2) molecular orbital theory calculations. For example, with C-terminal deprotonation of pentaglycine amide, formation of cm-2 - and a 6-membered ring diketopiperazine neutral requires >31.6 kcal/mol, which is 26.1 kcal/mol less than the analogous process involving the peptide acid. The end group specific fragmentation of peptide amides in the negative ion mode may be useful for identifying such groups in proteomic applications.

  12. Entrapment of methyl parathion hydrolase in cross-linked poly(γ-glutamic acid)/gelatin hydrogel.

    Science.gov (United States)

    Xie, Jianfei; Zhang, Huiwen; Li, Xu; Shi, Yuanliang

    2014-02-10

    Methyl parathion hydrolase (MPH) is an important enzyme in hydrolyzing toxic organophosphorus (OP) compounds. However, MPH is easily deactivated when subjected to extreme environmental conditions and is difficult to recover from the reaction system for reuse, thereby limiting its practical application. To address these shortcomings, we examined the entrapment of MPH in an environment-friendly, biocompatible and biodegradable cross-linked poly(γ-glutamic acid)/gelatin hydrogel. The cross-linked poly(γ-glutamic acid)/gelatin hydrogels were prepared with different gelatin/poly(γ-glutamic acid) mass ratios using water-soluble carbodiimide as the cross-linking agent. The MPH-entrapped cross-linked poly(γ-glutamic acid)/gelatin hydrogel (CPE-MPH) not only possessed improved thermostability, pH stability, and reusability but also exhibited enhanced efficiency in hydrolyzing OP compounds. Furthermore, CPE-MPH possesses high water-absorbing and water-retaining capabilities. We believe that the cross-linked poly(γ-glutamic acid)/gelatin hydrogels are an attractive carrier for the entrapment of diverse enzymes, affording a new approach for enzyme entrapment.

  13. Leukotriene A4 hydrolase: Selective abrogation of leukotriene B4 formation by mutation of aspartic acid 375

    Science.gov (United States)

    Rudberg, Peter C.; Tholander, Fredrik; Thunnissen, Marjolein M. G. M.; Samuelsson, Bengt; Haeggström, Jesper Z.

    2002-01-01

    Leukotriene A4 (LTA4, 5S-trans-5,6-oxido-7,9-trans-11,14-cis-eicosatetraenoic acid) hydrolase (LTA4H)/aminopeptidase is a bifunctional zinc metalloenzyme that catalyzes the final and rate-limiting step in the biosynthesis of leukotriene B4 (LTB4, 5S,12R-dihydroxy-6,14-cis-8,10-trans-eicosatetraenoic acid), a classical chemoattractant and immune modulating lipid mediator. Two chemical features are key to the bioactivity of LTB4, namely, the chirality of the 12R-hydroxyl group and the cis-trans-trans geometry of the conjugated triene structure. From the crystal structure of LTA4H, a hydrophilic patch composed of Gln-134, Tyr-267, and Asp-375 was identified in a narrow and otherwise hydrophobic pocket, believed to bind LTA4. In addition, Asp-375 belongs to peptide K21, a previously characterized 21-residue active site-peptide to which LTA4 binds during suicide inactivation. In the present report we used site-directed mutagenesis and x-ray crystallography to show that Asp-375, but none of the other candidate residues, is specifically required for the epoxide hydrolase activity of LTA4H. Thus, mutation of Asp-375 leads to a selective loss of the enzyme's ability to generate LTB4 whereas the aminopeptidase activity is preserved. We propose that Asp-375, possibly assisted by Gln-134, acts as a critical determinant for the stereoselective introduction of the 12R-hydroxyl group and thus the biological activity of LTB4. PMID:11917124

  14. Catalytic Kinetic Resolution of Saturated N-Heterocycles by Enantioselective Amidation with Chiral Hydroxamic Acids.

    Science.gov (United States)

    Kreituss, Imants; Bode, Jeffrey W

    2016-12-20

    The preparation of enantioenriched chiral compounds by kinetic resolution dates back to the laboratories of Louis Pasteur in the middle of the 19th century. Unlike asymmetric synthesis, this process can always deliver enantiopure material (ee > 99%) if the reactions are allowed to proceed to sufficient conversion and the selectivity of the process is not unity (s > 1). One of the most appealing and practical variants is acylative kinetic resolution, which affords easily separable reaction products, and several highly efficient enzymatic and small molecule catalysts are available. Unfortunately, this method is applicable to limited substrate classes such as alcohols and primary benzylamines. This Account focuses on our work in catalytic acylative kinetic resolution of saturated N-heterocycles, a class of molecules that has been notoriously difficult to access via asymmetric synthesis. We document the development of hydroxamic acids as suitable catalysts for enantioselective acylation of amines through relay catalysis. Alongside catalyst optimization and reaction development, we present mechanistic studies and theoretical calculation accounting for the origins of selectivity and revealing the concerted nature of many amide-bond forming reactions. Immobilization of the hydroxamic acid to form a polymer supported reagent allows simplification of the experimental setup, improvement in product purification, and extension of the substrate scope. The kinetic resolutions are operationally straight forward: reactions proceed at room temperature and open to air conditions, without generation of difficult-to-remove side products. This was utilized to achieve decagram scale resolution of antimalarial drug mefloquine to prepare more than 50 g of (+)-erythro-meflqouine (er > 99:1) from the racemate. The immobilized quasienantiomeric acyl hydroxamic acid reagents were also exploited for a rare practical implementation of parallel kinetic resolution that affords both enantiomers of

  15. Synthesis and structural studies of amino amide salts derived from 2-(aminomethyl)benzimidazole and α-amino acids

    Science.gov (United States)

    Avila-Montiel, Concepción; Tapia-Benavides, Antonio R.; Falcón-León, Martha; Ariza-Castolo, Armando; Tlahuext, Hugo; Tlahuextl, Margarita

    2015-11-01

    2-{[(Ammoniumacetyl)amino]methyl}-1H-benzimidazol-3-ium dichloride 4, 2-{[(2-ammoniumpropanoyl)amino]methyl}-1H-benzimidazol-3-ium dichloride 5, and 2-{[(2-ammonium-3-phenylpropanoyl)amino]methyl}-1H-benzimidazol-3-ium dichloride 6 amino amides were synthesized via condensation of 2AMBZ dihydrochloride with the corresponding amino acid. Compounds 7-12 were obtained by replacing chloride ions (in salts 4-6) with nitrate or tetrachlorozincate ions. The results of X-ray diffraction crystallographic studies indicated that the geometries, charges and sizes of the anions are essential for the formation of the strong hydrogen bond interactions of compounds 4, 5, 9-12. Moreover, in most cases, the presence of water and solvent molecules stabilizes the supramolecular structures of these compounds. Nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy indicated that the presence of chloride or tetrachlorozincate anions increases the acidity of the benzimidazolic and amide groups more significantly than the presence of nitrate anions. However, Quantum Theory of Atoms in Molecules (QTAIM) computations of the crystal structures demonstrate that amino amides interact more strongly with NO3- than with Cl- and ZnCl42- anions; this difference explains the spectroscopic results.

  16. A conceptual DFT approach towards analysing feasibility of the intramolecular cycloaddition Diels-Alder reaction of triene amide in Lewis acid catalyst

    Indian Academy of Sciences (India)

    ABDELILAH BENALLOU; HABIB EL ALAOUI EL ABDALLAOUI; HOCINE GARMES

    2016-09-01

    The effect of Lewis acid catalysts, TiCl₄ and Et₂AlCl on the intramolecular cycloaddition Diels- Alder (IMDA) reaction of triene-amide have been studied theoretically using the DFT (Density Functional Theory) at the 6-31G(d,p) level of theory. The results obtained using the polar model of Domingo, electrophilicity, nucleophilicity indices and thermochemistry computations, demonstrate that these catalysts are coordinated with more nucleophilic atoms of diene fragment (nitrogen and oxygen of amide group). These catalysts affect negatively the feasibility of the reaction as well as the physico-chemical parameters of the IMDA reaction of triene-amide.

  17. Solid phase synthesis of fatty acid modified glucagon-like peptide-1(7-36) amide under thermal and controlled microwave irradiation

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fatty acid modified glucagon-like peptide-1(7-36) amide was synthesized efficiently on Rink-Amide-MBHA resin by microwave-assisted solid phase method.The method of thermal and controlled microwave irradiation provided impressive enhancements in product yield,selectivity,and reaction rate.The coupling time was dramatically decreased to 6 min,and the desired products were obtained in high yield and purity.

  18. Generation of novel cationic antimicrobial peptides from natural non-antimicrobial sequences by acid-amide substitution

    Directory of Open Access Journals (Sweden)

    Tamada Yasushi

    2011-03-01

    Full Text Available Abstract Background Cationic antimicrobial peptides (CAMPs are well recognized to be promising as novel antimicrobial and antitumor agents. To obtain novel skeletons of CAMPs, we propose a simple strategy using acid-amide substitution (i.e. Glu→Gln, Asp→Asn to confer net positive charge to natural non-antimicrobial sequences that have structures distinct from known CAMPs. The potential of this strategy was verified by a trial study. Methods The pro-regions of nematode cecropin P1-P3 (P1P-P3P were selected as parent sequences. P1P-P3P and their acid-amide-substituted mutants (NP1P-NP3P were chemically synthesized. Bactericidal and membrane-disruptive activities of these peptides were evaluated. Conformational changes were estimated from far-ultraviolet circular dichroism (CD spectra. Results NP1P-NP3P acquired potent bactericidal activities via membrane-disruption although P1P-P3P were not antimicrobial. Far-ultraviolet CD spectra of NP1P-NP3P were similar to those of their parent peptides P1P-P3P, suggesting that NP1P-NP3P acquire microbicidal activity without remarkable conformational changes. NP1P-NP3P killed bacteria in almost parallel fashion with their membrane-disruptive activities, suggesting that the mode of action of those peptides was membrane-disruption. Interestingly, membrane-disruptive activity of NP1P-NP3P were highly diversified against acidic liposomes, indicating that the acid-amide-substituted nematode cecropin pro-region was expected to be a unique and promising skeleton for novel synthetic CAMPs with diversified membrane-discriminative properties. Conclusions The acid-amide substitution successfully generated some novel CAMPs in our trial study. These novel CAMPs were derived from natural non-antimicrobial sequences, and their sequences were completely distinct from any categories of known CAMPs, suggesting that such mutated natural sequences could be a promising source of novel skeletons of CAMPs.

  19. Poly(amic acid)s and their poly(amide imide) counterparts containing azobenzene moieties: Characterization, imidization kinetics and photochromic properties

    Energy Technology Data Exchange (ETDEWEB)

    Konieczkowska, Jolanta [Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Curie-Sklodowska Str., 41-819 Zabrze (Poland); Institute of Chemistry, University of Silesia, 9 Szkolna Str., 40-006 Katowice (Poland); Janeczek, Henryk [Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Curie-Sklodowska Str., 41-819 Zabrze (Poland); Kozanecka-Szmigiel, Anna, E-mail: annak@if.pw.edu.pl [Faculty of Physics, Warsaw University of Technology, 75 Koszykowa Str., 00-662 Warszawa (Poland); Schab-Balcerzak, Ewa, E-mail: eschab-balcerzak@cmpw-pan.edu.pl [Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Curie-Sklodowska Str., 41-819 Zabrze (Poland)

    2016-09-01

    We report on a series of novel photochromic poly(amide imide)s and their poly(amic acid) precursors bearing azobenzene chromophores as the side groups. The chemical structures of the polymers were designed so that they exhibited an enhanced thermal stability combined with a large and stable birefringence photogenerated by light of the wavelengths belonging to a wide spectral range. The polymers possessed rigidly attached azochromophores in the content of either one or two per a repeating unit, which in the latter case differed in their structures. The imidization kinetics of the poly(amic acid)s was investigated by differential scanning calorimetry and the kinetic parameters were estimated using Ozawa and Kissinger methods. Measurements of the selected physical properties of the polymers, such as solubility, supramolecular structure, linear absorption, thermal stability, glass transition and photochromic response were performed and used for determination of the structure-property relations. The measurements of photochromic properties showed a very efficient generation of optical anisotropy upon blue and violet irradiation, for both the poly(amide imide)s containing two different chromophores in the repeating unit and for their precursors. For these poly(amide imide)s and for their precursors an exceptionally slow decrease in the photoinduced optical anisotropy in the dark was also observed. - Highlights: • Three azopoly(amide imide)s were obtained from azopoly(amic acid)s. • Chosen physicochemical properties and photochromic responses were measured. • Desired optical response was found for polymers with two azo-dyes in repeating unit. • Structure-property relations were shown.

  20. Synthesis, Properties and Applications of Biodegradable Polymers Derived from Diols and Dicarboxylic Acids: From Polyesters to Poly(ester amides

    Directory of Open Access Journals (Sweden)

    Angélica Díaz

    2014-04-01

    Full Text Available Poly(alkylene dicarboxylates constitute a family of biodegradable polymers with increasing interest for both commodity and speciality applications. Most of these polymers can be prepared from biobased diols and dicarboxylic acids such as 1,4-butanediol, succinic acid and carbohydrates. This review provides a current status report concerning synthesis, biodegradation and applications of a series of polymers that cover a wide range of properties, namely, materials from elastomeric to rigid characteristics that are suitable for applications such as hydrogels, soft tissue engineering, drug delivery systems and liquid crystals. Finally, the incorporation of aromatic units and α-amino acids is considered since stiffness of molecular chains and intermolecular interactions can be drastically changed. In fact, poly(ester amides derived from naturally occurring amino acids offer great possibilities as biodegradable materials for biomedical applications which are also extensively discussed.

  1. Variants of glycoside hydrolases

    Energy Technology Data Exchange (ETDEWEB)

    Teter, Sarah (Davis, CA); Ward, Connie (Hamilton, MT); Cherry, Joel (Davis, CA); Jones, Aubrey (Davis, CA); Harris, Paul (Carnation, WA); Yi, Jung (Sacramento, CA)

    2011-04-26

    The present invention relates to variants of a parent glycoside hydrolase, comprising a substitution at one or more positions corresponding to positions 21, 94, 157, 205, 206, 247, 337, 350, 373, 383, 438, 455, 467, and 486 of amino acids 1 to 513 of SEQ ID NO: 2, and optionally further comprising a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2 a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2, wherein the variants have glycoside hydrolase activity. The present invention also relates to nucleotide sequences encoding the variant glycoside hydrolases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

  2. Epoxy fatty acids and inhibition of the soluble epoxide hydrolase selectively modulate GABA mediated neurotransmission to delay onset of seizures.

    Directory of Open Access Journals (Sweden)

    Bora Inceoglu

    Full Text Available In the brain, seizures lead to release of large amounts of polyunsaturated fatty acids including arachidonic acid (ARA. ARA is a substrate for three major enzymatic routes of metabolism by cyclooxygenase, lipoxygenase and cytochrome P450 enzymes. These enzymes convert ARA to potent lipid mediators including prostanoids, leukotrienes and epoxyeicosatrienoic acids (EETs. The prostanoids and leukotrienes are largely pro-inflammatory molecules that sensitize neurons whereas EETs are anti-inflammatory and reduce the excitability of neurons. Recent evidence suggests a GABA-related mode of action potentially mediated by neurosteroids. Here we tested this hypothesis using models of chemically induced seizures. The level of EETs in the brain was modulated by inhibiting the soluble epoxide hydrolase (sEH, the major enzyme that metabolizes EETs to inactive molecules, by genetic deletion of sEH and by direct administration of EETs into the brain. All three approaches delayed onset of seizures instigated by GABA antagonists but not seizures through other mechanisms. Inhibition of neurosteroid synthesis by finasteride partially blocked the anticonvulsant effects of sEH inhibitors while the efficacy of an inactive dose of neurosteroid allopregnanolone was enhanced by sEH inhibition. Consistent with earlier findings, levels of prostanoids in the brain were elevated. In contrast, levels of bioactive EpFAs were decreased following seizures. Overall these results demonstrate that EETs are natural molecules which suppress the tonic component of seizure related excitability through modulating the GABA activity and that exploration of the EET mediated signaling in the brain could yield alternative approaches to treat convulsive disorders.

  3. Characterisation of a 1,4-ß-fucoside hydrolase degrading colanic acid

    NARCIS (Netherlands)

    Verhoef, R.P.; Beldman, G.; Schols, H.A.; Siika-aho, M.; Ratto, M.; Buchert, J.; Voragen, A.G.J.

    2005-01-01

    A novel colanic acid-degrading enzyme was isolated from a mixed culture filtrate obtained by enrichment culturing of a compost sample using colanic acid as carbon source. The enzyme was partially purified resulting in a 17-fold increase in specific activity. Further purification by Native PAGE revea

  4. Cysteine amide adduct formation from carboxylic acid drugs via UGT-mediated bioactivation in human liver microsomes.

    Science.gov (United States)

    Harada, H; Toyoda, Y; Endo, T; Kobayashi, M

    2015-10-01

    Although chemical trapping has been widely used to evaluate cytochrome P450-mediated drug bioactivation, thus far, only a few in vitro-trapping studies have been performed on UDP-glucuronosyltransferase (UGT)-mediated drug bioactivation. In this study, we used cysteine (Cys) as trapping agent to gain new insights into the UGT-mediated bioactivation involving acyl glucuronides of carboxylic acid drugs. Diclofenac, ketoprofen and ibuprofen were incubated in human liver microsomes with UDPGA and Cys, followed by analysis using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). The N-acyl-Cys amide adduct of diclofenac was characterized by mass analysis and was detectable even in photodiode array analysis. Our data indicated that the formation of such adducts reflects the reactivity of the corresponding acyl glucuronides. In addition, it was suggested that the adduct formation requires an N-terminal Cys moiety with both a free amine and a free thiol group, from the results using various cysteine derivatives. We propose that the S-acyl-Cys thioester adduct can form via transacylation of an acyl glucuronide and can then form to an N-acyl-Cys amide adduct through intramolecular S- to N-acyl rearrangement. This series of the reactions has important implications as a possible bioactivation mechanism for covalent binding of carboxylic acid drugs to macromolecules.

  5. Synthesis and structure--activity relationships of substituted cinnamic acids and amide analogues: a new class of herbicides.

    Science.gov (United States)

    Vishnoi, Shipra; Agrawal, Vikash; Kasana, Virendra K

    2009-04-22

    In the present investigation, substituted cinnamic acids (3-hydroxy, 4-hydroxy, 2-nitro, 3-nitro, 4-nitro, 3-chloro, and 4-methoxy) and their amide analogues with four different types of substituted anilines have been synthesized. The synthesized compounds have been screened for their germination inhibition activity on radish (Raphanus sativus L. var. Japanese White) seeds at 50, 100, and 200 ppm concentrations, and the activity was compared with standard herbicide, metribuzin formulation (sencor). Significant activity was exhibited by all of the compounds. It was observed that with the increase in concentration of the test solution, the activity also increased. All of the compounds showed more than 70% inhibition at 100 ppm concentration except 4-hydroxy cinnamanilide. The compound, 2-chloro (4'-hydroxy) cinnamanilide was the best among the tested compounds, and it was found to be at par with the standard, metribuzin at all concentrations. Thus, it can be concluded that substituted cinnamic acids and their amide analogues may be developed as potential herbicides.

  6. Transgenic tomato plants overexpressing tyramine N-hydroxycinnamoyltransferase exhibit elevated hydroxycinnamic acid amide levels and enhanced resistance to Pseudomonas syringae.

    Science.gov (United States)

    Campos, Laura; Lisón, Purificación; López-Gresa, María Pilar; Rodrigo, Ismael; Zacarés, Laura; Conejero, Vicente; Bellés, José María

    2014-10-01

    Hydroxycinnamic acid amides (HCAA) are secondary metabolites involved in plant development and defense that have been widely reported throughout the plant kingdom. These phenolics show antioxidant, antiviral, antibacterial, and antifungal activities. Hydroxycinnamoyl-CoA:tyramine N-hydroxycinnamoyl transferase (THT) is the key enzyme in HCAA synthesis and is induced in response to pathogen infection, wounding, or elicitor treatments, preceding HCAA accumulation. We have engineered transgenic tomato plants overexpressing tomato THT. These plants displayed an enhanced THT gene expression in leaves as compared with wild type (WT) plants. Consequently, leaves of THT-overexpressing plants showed a higher constitutive accumulation of the amide coumaroyltyramine (CT). Similar results were found in flowers and fruits. Moreover, feruloyltyramine (FT) also accumulated in these tissues, being present at higher levels in transgenic plants. Accumulation of CT, FT and octopamine, and noradrenaline HCAA in response to Pseudomonas syringae pv. tomato infection was higher in transgenic plants than in the WT plants. Transgenic plants showed an enhanced resistance to the bacterial infection. In addition, this HCAA accumulation was accompanied by an increase in salicylic acid levels and pathogenesis-related gene induction. Taken together, these results suggest that HCAA may play an important role in the defense of tomato plants against P. syringae infection.

  7. Preparation and surface active properties of oxypropylated diol monoesters of fatty acids with an amide oxime terminal group

    Directory of Open Access Journals (Sweden)

    Eissa, A. M.F.

    1994-10-01

    Full Text Available Locally produced non-edible oil, namely, rice bran oil (R.B.O. was utilized as starting materials for preparing new nonionic surfactant. Oxypropylated diol monoesters of linoleic and rice bran oil fatty acids were prepared. Also amide oxime derivatives were obtained. Surface active properties of these compounds were measured. Under neutral condition amide eximes served as nonionic surfactants and their properties were similar to other oxypropylated monoesters.

    Se ha utilizado un aceite no comestible de producción local, denominado, aceite de salvado de arroz (R.B.O. como materia prima para la preparación de nuevos tensioactivos no iónicos. Se prepararon diol monoésteres oxipropilados de ácido linoleico y ácidos grasos de aceite de salvado de arroz. También se obtuvieron los derivados de amido oxima. Se midieron las propiedades de tensión superficial de estos compuestos. Bajo condiciones neutras las amido eximas sirvieron como tensioactivos no iónicos y sus propiedades fueron similares a los de otros monoésteres oxipropilados.

  8. Enantioselective synthesis and teratogenicity of propylisopropyl acetamide, a CNS-active chiral amide analogue of valproic acid.

    Science.gov (United States)

    Spiegelstein, O; Bialer, M; Radatz, M; Nau, H; Yagen, B

    1999-01-01

    Propylisopropyl acetamide (PID), an amide analogue of the major antiepileptic drug valproic acid (VPA), possesses favorable anticonvulsant and CNS properties. PID contains one chiral carbon atom and therefore exists in two enantiomeric forms. The purpose of this work was to synthesize the two PID enantiomers and evaluate their enantiospecific teratogenicity. Enantioselective synthesis of PID enantiomers was achieved by coupling valeroyl chloride with optically pure (4S)- and (4R)-benzyl-2-oxazolidinone chiral auxiliaries. The two oxazolidinone enolates were alkylated with isopropyl triflate, hydrolyzed, and amidated to yield (2R)- and (2S)-PID. These two PID enantiomers were obtained with excellent enantiomeric purity, exceeding 99.4%. Unlike VPA, both (2R)- and (2S)-PID failed to exert teratogenic effects in NMRI mice following a single 3 mmol/kg subcutaneous injection. From this study we can conclude that individual PID enantiomers do not demonstrate stereoselective teratogenicity in NMRI mice. Due to its better anticonvulsant activity than VPA and lack of teratogenicity, PID (in a stereospecific or racemic form) has the potential to become a new antiepileptic and CNS drug.

  9. [Production of hydrolases by lactic acid bacteria and bifidobacteria and their antibiotic resistance].

    Science.gov (United States)

    Novik, G I; Astanovich, N I; Riabaia, N E

    2007-01-01

    It was demonstrated that bifidobacteria and lactic acid bacteria B. adolescentis and Lactobacillus sp. synthesized extracellular enzymes cleaving glycoside bonds in the molecules of dextran, pectic acid, and soluble starch. The maximal production of extracellular beta-galactosidase by B. adolescentis 91-BIM and 94-BIM at a rate of 0.08 and 0.03 U/mg h was observed during the exponential growth phase at 5 and 12 h of cultivation, respectively. The cultures of bifidobacteria retained 60-70% of beta-galactosidase and alpha-amylase activities after six months of storage. The bifidobacterium strains studied were resistant to amphotericin and aminoglycosides (gentamicin, kanamycin, and netromycin). The lactam antibiotics (ampicillin, benzylpenicillin, bicillin 3, bicillin 5, and carbenicillin), the preparations inhibiting protein synthesis at the level of ribosomes (lincomycin), RNA polymerase inhibitors (rifampin), cephalosporin, and Maxipime inhibited the growth of bifidobacteria. Rifampin, erythromycin, amphotericin, Maxipime, Fortum, doxycycline, levomycetin, streptomycin, and the aminoglycosides netromycin, gentamicin, and kanamycin did not have an effect on the growth of Lactobacillus sp., whereas semisynthetic derivatives of penicillin, carbenicillin and ampicillin, inhibited its growth as well as Oxamp and lincomycin. The lactam antibiotics benzylpenicillin, bicillin 3, and bicillin 5 inhibited the growth of lactic acid bacilli by 30-90%.

  10. Copper(II) complexes of bis(amino amide) ligands: effect of changes in the amino acid residue.

    Science.gov (United States)

    Martí, Inés; Ferrer, Armando; Escorihuela, Jorge; Burguete, M Isabel; Luis, Santiago V

    2012-06-14

    A family of ligands derived from bis(amino amides) containing aliphatic spacers has been prepared, and their protonation and stability constants for the formation of Cu(2+) complexes have been determined potentiometrically. Important differences are associated to both the length of the aliphatic spacer and the nature of the side chains derived from the amino acid. In general, ligands containing aliphatic side chains display higher basicities as well as stability constants with Cu(2+). In the same way, basicities and stability constants tend to increase when decreasing the steric hindrance caused by the corresponding side-chain. FT-IR, UV-vis and ESI-MS were used for analyzing the complex species detected in the speciation diagram. UV-vis studies showed the presence of different coordination environments for the copper(II) complexes. Complexes with different stoichiometries can be formed in some instances. This was clearly highlighted with the help of ESI-MS experiments.

  11. Synthesis and Crystal Structure of 1-H-Pyrrole-2-carboxylic Acid [2-(Naphthalen-1-ylamino)-ethyl]-amide

    Institute of Scientific and Technical Information of China (English)

    YIN Zhen-Ming; WANG Jian-Ying

    2006-01-01

    1-H-Pyrrole-2-carboxylic acid [2-(naphthalen-1-ylamino)-ethyl]-amide has been synthesized and characterized. Its crystal is of monoclinic, space group P21/n with a = 5.930(6), b =12.144(13), c = 20.10(2) (A),β = 95.709(17)°, V= 1441(3) (A), Z= 4, C17H17N3O, Mr= 279.34, Dc=1.288 g/cm3, F(000) = 592, μ(MoKα) = 0.083 mm-1, S = 1.019, R = 0.0473 and wR = 0.1181 for 1713 observed reflections with 1 > 2σ(Ⅰ). X-ray diffraction reveals that two molecules of the title compound form a dimer through a pair of N-H…O hydrogen bonds.

  12. Reactivity of a Nickel(II) Bis(amidate) Complex with meta-Chloroperbenzoic Acid : Formation of a Potent Oxidizing Species

    NARCIS (Netherlands)

    Corona, Teresa; Pfaff, Florian F; Acuña-Parés, Ferran; Draksharapu, Apparao; Whiteoak, Christopher J; Martin-Diaconescu, Vlad; Lloret-Fillol, Julio; Browne, Wesley R; Ray, Kallol; Company, Anna

    2015-01-01

    Herein, we report the formation of a highly reactive nickel-oxygen species that has been trapped following reaction of a Ni(II) precursor bearing a macrocyclic bis(amidate) ligand with meta-chloroperbenzoic acid (HmCPBA). This compound is only detectable at temperatures below 250 K and is much more

  13. 芥酸酰胺丙基甜菜碱的合成与性能评价%Synthesis and Property Evaluation of Erucic Acid Amide Propyl Betaine

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    With erucic acid, N, N - dimethyl trimethylene diamine and sodium chloroacetate as raw materials, erucic acid amide carboxy propyl betaine was synthesized via amidation and quaternarization reactions.The optimal synthesis conditions were studied. The target product was characterized by IR spectrum, and its property was evaluated. The results show that when the concentration of erucic acid amide propyl betaine is 4%, the concentration of HCl is 10%, the viscosity of acid liquid system is the maximum;When the concentration of erucic acid amide propyl betaine is more than 4%, the viscosity increase increases first and then decreases with temperature increasing;When the concentration of erucic acid amide propyl betaine is less than 4%, the viscosity decreases with temperature increasing.%以芥酸、N,N-二甲基-1,3-丙二胺与氯乙酸钠为原料,经过酰胺化和季铵化两步反应,合成了芥酸酰胺丙基甜菜碱。研究了最优合成条件,采用红外光谱对目标产物进行表征。芥酸酰胺丙基甜菜碱浓度为4%,HCl 浓度为10%时,酸液体系黏度最大。当芥酸酰胺丙基甜菜碱浓度大于4%时,黏度随温度升高而先增加后减小;当芥酸酰胺丙基甜菜碱浓度小于4%时,黏度随温度升高而降低。

  14. "S" shaped organotin(IV) carboxylates based on amide carboxylic acids: Syntheses, crystal structures and antitumor activities

    Science.gov (United States)

    Xiao, Xiao; Li, Yan; Dong, Yuan; Li, Wenliang; Xu, Kun; Shi, Nianqiu; Liu, Xin; Xie, Jingyi; Liu, Peigen

    2017-02-01

    Three organotin carboxylates based on amide carboxylic acids: (Ph3Sn)2(L1) (1) (L1 = 3,3‧-(1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f]isoindole-2,6(1H,3H)-diyl)dipropionic acid), (Ph3Sn)2(L2)·C7H8 (2) (L2 = 3,3‧-(1,3,6,8-tetraoxo-1,3,6,8-tetrahydrobenzo [lmn][3,8]phenanthroline-2,7-diyl)dipropionic acid), [(Ph3Sn)(CH3CH2O)]2(L3) (3) (L3 = 2,2‧-(1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f]isoindole-2,6(1H,3H)-diyl) dibenzoic acid) were synthesized and characterized by elemental analysis, IR, 1H, 13C, 119Sn NMR spectroscopy and X-ray crystallography diffraction analyses. Complexes 1-3 are di-nuclear triphenlytin carboxylates owning "S" shaped monomer structures. Ligands in 1-3 adopt unidentate coordination. Intermolecular hydrogen bonds and Sn···O interactions help complexes 1-3 build their supramolecular structures which are discussed in detail. The preliminary antitumor activities of 1-3 against HepG2 cell lines have also been studied.

  15. Towards novel 5-HT7versus 5-HT1A receptor ligands among LCAPs with cyclic amino acid amide fragments: design, synthesis, and antidepressant properties. Part II.

    Science.gov (United States)

    Canale, Vittorio; Kurczab, Rafał; Partyka, Anna; Satała, Grzegorz; Witek, Jagna; Jastrzębska-Więsek, Magdalena; Pawłowski, Maciej; Bojarski, Andrzej J; Wesołowska, Anna; Zajdel, Paweł

    2015-03-06

    A 26-membered library of novel long-chain arylpiperazines, which contained primary and tertiary amides of cyclic amino acids (proline and 1,2,3,4-tetrahydroisoquinoline-3-carboxamide) in the terminal fragment was synthesized and biologically evaluated for binding affinity for 5-HT7 and 5-HT1A receptors. Docking studies confirmed advantages of Tic-amide over Pro-amide fragment for interaction with 5-HT7 receptors. Selected compounds 32 and 28, which behaved as 5-HT7Rs antagonist and 5-HT1A partial agonist, respectively, produced antidepressant-like effects in the forced swim test in mice after acute treatment in doses of 10 mg/kg (32) and 1.25 mg/kg (28). Compound 32 reduced immobility in a manner similar to the selective 5-HT7 antagonist SB-269970.

  16. Solution-phase Synthesis of a Combinatorial Library of 3-[4-(Coumarin-3-yl-1,3-thiazol-2-ylcarbamoyl]propanoic acid Amides

    Directory of Open Access Journals (Sweden)

    V. Chernykh

    2005-02-01

    Full Text Available The parallel solution-phase synthesis of a new combinatorial library of 3-[4-(R1-coumarin-3-yl-1,3-thiazol-2-ylcarbamoyl]propanoic acid amides 9 has been developed. The synthesis involves two steps: 1 the synthesis of core building blocks – 3- [4-(coumarin-3-yl-1,3-thiazol-2-ylcarbamoyl]propanoic acids, 6 – by the reaction of 3-(ω-bromacetylcoumarins 1 with 3-amino(thioxomethylcarbamoylpropanoic acid (5; 2 the synthesis of the corresponding 3-[4-(coumarin-3-yl-1,3-thiazol-2-yl- carbamoyl]propanoic acids amides 9 using 1,1’-carbonyldimidazole as a coupling reagent. The advantages of the method compared to existing ones are discussed.

  17. Influence of ascorbic acid on in vivo amidation of alpha-melanocyte stimulating hormone in guinea pig pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Hilsted, L

    1988-01-01

    The effect of ascorbic acid depletion on the amidation of alphamelanocyte stimulating hormone (alpha MSH) was studied in vivo in guinea pig pituitary. After four weeks, the concentration of ascorbic acid was 1.20 +/- 0.11 mumol/g tissue (mean +/- SD) in the pituitary and 0.34 +/- 0.07 mumol....../g tissue in the cerebral cortex from the depleted animals versus 7.58 +/- 0.08 and 1.51 +/- 0.32 mumol/g tissue, respectively, in the control animals. In the pituitaries from the animals depleted of ascorbate (N = 4), the relative amount of alpha MSH was reduced to approximately half the values obtained......-39) immunoreactivity was observed in the depleted guinea pigs. Gel chromatography and reversed-phase high-performance luquid chromatography showed that the alpha MSH and ACTH (1-14) immunoreactivity was of low molecular weight and partly mono- or diacetylated. Depletion of ascorbic acid had no influence on the degree...

  18. Synthesis and comprehensive structural studies of a novel amide based carboxylic acid derivative: Non-covalent interactions

    Science.gov (United States)

    Chahkandi, Mohammad; Bhatti, Moazzam H.; Yunus, Uzma; Shaheen, Shahida; Nadeem, Muhammad; Tahir, Muhammad Nawaz

    2017-04-01

    The presented work studies the geometric and electronic structures of the crystalline network of a novel amide based carboxylic acid derivative, N-[(4-chlorophenyl)]-4-oxo-4-[oxy] butane amide, C10H10NO3Cl (1), constructed via hydrogen bonds (HBs) and stacking non-covalent interactions. Compound 1 was synthesized and characterized by FTIR, 1H, and 13C NMR, and UV-Vis spectra, X-ray structural, DTA-TG, and EI-MS, analyses. DFT calculations about molecular and related network of 1 were performed at hybrid B3LYP/6-311+G (d, p) level of theory to support the experimental data. The neutral monomeric structures join together via inter-molecular conventional O/Nsbnd H⋯O and non-conventional Csbnd H⋯O HBs and Osbnd H···π and Csbnd O···π stacking interactions to create 2-D architecture of the network. The results of dispersion corrected density functional theory (DFT-D) calculations within the binding energy of the constructive non-covalent interactions demonstrate that HBs, especially conventional Osbnd H⋯O and Nsbnd H⋯O, govern the network formation. The calculated electronic spectrum show six major bands in the range of 180-270 nm which confirm the experimental one within an intense band around 250 nm. These charge transfer bands result from shift of lone pair electron density of phenyl to chlorine or hydroxyl or phenyl functional groups that possess π → π* and π → n characters.

  19. Secondary amides of (R)-3,3,3-trifluoro-2-hydroxy-2-methylpropionic acid as inhibitors of pyruvate dehydrogenase kinase.

    Science.gov (United States)

    Aicher, T D; Anderson, R C; Gao, J; Shetty, S S; Coppola, G M; Stanton, J L; Knorr, D C; Sperbeck, D M; Brand, L J; Vinluan, C C; Kaplan, E L; Dragland, C J; Tomaselli, H C; Islam, A; Lozito, R J; Liu, X; Maniara, W M; Fillers, W S; DelGrande, D; Walter, R E; Mann, W R

    2000-01-27

    N'-methyl-N-(4-tert-butyl-1,2,5,6-tetrahydropyridine)thiourea, SDZ048-619 (1), is a modest inhibitor (IC(50) = 180 microM) of pyruvate dehydrogenase kinase (PDHK). In an optimization of the N-methylcarbothioamide moiety of 1, it was discovered that amides with a small acyl group, in particular appropriately substituted amides of (R)-3,3,3-trifluoro-2-hydroxy-2-methylpropionic acid, are inhibitors of PDHK. Utilizing this acyl moiety, herein is reported the rationale leading to the optimization of a series of acylated piperazine derivatives. Methyl substitution of the piperazine at the 2- and 5-positions (with S and R absolute stereochemistry) markedly increased the potency of the lead compound (>1,000-fold). Oral bioavailability of the compounds in this series is good and is optimal (as measured by AUC) when the 4-position of the piperazine is substituted with an electron-poor benzoyl moiety. (+)-1-N-[2,5-(S, R)-Dimethyl-4-N-(4-cyanobenzoyl)piperazine]-(R)-3,3, 3-trifluoro-2-hydroxy-2-methylpropanamide (14e) inhibits PDHK in the primary enzymatic assay with an IC(50) of 16 +/- 2 nM, enhances the oxidation of [(14)C]lactate into (14)CO(2) in human fibroblasts with an EC(50) of 57 +/- 13 nM, diminishes lactate significantly 2.5 h post-oral-dose at doses as low as 1 micromol/kg, and increases the ex vivo activity of PDH in muscle, liver, and fat tissues in normal Sprague-Dawley rats. These PDHK inhibitors, however, do not lower glucose in diabetic animal models.

  20. New optically active poly(amide-imide)s based on N,N '-(pyromellitoyl)-bis-L-amino acid and methylene diphenyl-4,4 '-diisocyanate

    DEFF Research Database (Denmark)

    Tian, Xiaoyu; Yao, Jinshui; Zhang, Xian;

    2014-01-01

    Five new optically active poly(amide-imide)s were synthesized through the direct polycondensation reaction between chiral N,N-(pyromellitoyl)-bis-L-amino acids and methylene diphenyl-4,4-diisocyanate in a medium consisting of N-methyl-2-pyrrolidone (NMP) and xylene. The resulted polymers were fully......,N-dimethyl formamide, dimethyl sulfoxide (DMSO), NMP, sulfuric acid, and para-methyl phenol. Same specific rotations of these polymers in these different solvents were obtained....

  1. Design and Synthesis of Bis-amide and Hydrazide-containing Derivatives of Malonic Acid as Potential HIV-1 Integrase Inhibitors

    Directory of Open Access Journals (Sweden)

    Nouri Neamati

    2008-10-01

    Full Text Available HIV-1 integrase (IN is an attractive and validated target for the development of novel therapeutics against AIDS. In the search for new IN inhibitors, we designed and synthesized three series of bis-amide and hydrazide-containing derivatives of malonic acid. We performed a docking study to investigate the potential interactions of the title compounds with essential amino acids on the IN active site.

  2. Efficacy of boswellic acid on lysosomal acid hydrolases, lipid peroxidation and anti-oxidant status in gouty arthritic mice

    Institute of Scientific and Technical Information of China (English)

    Evan Prince Sabina; Haridas Indu; Mahaboobkhan Rasool

    2012-01-01

    Objective:To evaluate the efficacy of boswellic acid against monosodium urate crystal-induced inflammation in mice. Methods:The mice were divided into four experimental groups. Group I served as control;mice in group II were injected with monosodium urate crystal;group III consisted of monosodium urate crystal-induced mice who were treated with boswellic acid (30 mg/kg/b.w.);group IV comprised monosodium urate crystal-induced mice who were treated with indomethacin (3 mg/kg/b.w.). Paw volume and levels/activities of lysosomal enzymes, lipid peroxidation, anti-oxidant status and inflammatory mediator TNF-αwere determined in control and monosodium urate crystal-induced mice. In addition, the levels of β-glucuronidase and lactate dehydrogenase were also measured in monosodium urate crystal-incubated polymorphonuclear leucocytes (PMNL) in vitro. Results:The activities of lysosomal enzymes, lipid peroxidation, and tumour necrosis factor-αlevels and paw volume were increased significantly in monosodium urate crystal-induced mice, whereas the activities of antioxidant status were in turn decreased. However, these changes were modulated to near normal levels upon boswellic acid administration. In vitro, boswellic acid reduced the level of β-glucuronidase and lactate dehydrogenase in monosodium urate crystal-incubated PMNL in concentration dependent manner when compared with control cells. Conclusions: The results obtained in this study further strengthen the anti-inflammatory/antiarthritic effect of boswellic acid, which was already well established by several investigators.

  3. Application of cyanuric chloride-based six new chiral derivatizing reagents having amino acids and amino acid amides as chiral auxiliaries for enantioresolution of proteinogenic amino acids by reversed-phase high-performance liquid chromatography.

    Science.gov (United States)

    Bhushan, Ravi; Dixit, Shuchi

    2012-04-01

    Six dichloro-s-triazine (DCT) reagents having L-Leu, D-Phg, L-Val, L-Met, L-Ala and L-Met-NH(2) as chiral auxiliaries in cyanuric chloride were introduced for enantioseparation of 13 proteinogenic amino acids. Four other DCTs and six monochloro-s-triazine (MCT) reagents having amino acid amides as chiral auxiliaries were also synthesized. These 16 chiral derivatizing reagents (CDRs) were used for synthesis of diastereomers of all the 13 analytes using microwave irradiation, which were resolved by reversed-phase high-performance liquid chromatography (RP-HPLC) using C18 column and gradient eluting mixture of aqueous TFA and acetonitrile with UV detection at 230 nm. It required only 60-90 s for derivatization using microwave irradiation. Better resolution and lower retention times were observed for the diastereomers prepared with CDRs having amino acids as chiral auxiliaries as compared to counterparts prepared with reagents having amino acid amides as chiral auxiliaries. As the best resolution of all the 13 analytes was observed for their diastereomers prepared using the DCT reagent having L-Leu as chiral auxiliary, this CDR was further employed for derivatization of Lys, Tyr, His and Arg followed by RP-HPLC analysis of resulting diastereomers. The results are discussed in light of acid and amide groups of chiral auxiliaries constituting CDRs, electronegativities of the atoms of achiral moieties constituting CDRs and hydrophobicities of side chains of amino acids constituting CDRs and analytes.

  4. Synthesis and characterization of new optically active copoly(amid-imide)s based on N-phthalimido-L-aspartic acid and aromatic diamines

    Institute of Scientific and Technical Information of China (English)

    Khalil; Faghihi; Hamidreza; Alimohammadi

    2010-01-01

    In this article,six new optically active copoly(amide-imide)s(10a-f) were synthesized through the direct polycondensation reaction of N-phthalimido-L-aspartic acid(4) with 1,5-diamino naphthalene(8),3,4-diamino benzophenone(9) in the presence of therphthahc acid(7),fumaric acid(6) and adipic acid(5) as a second diacid in a medium consisting of N-methyl-2-pyrrolidone,triphenyl phosphite, calcium chloride and pyridine.The resulting copolymers were fully characterized by means of FT-IR spectroscopy,elementa...

  5. Brucella abortus choloylglycine hydrolase affects cell envelope composition and host cell internalization.

    Directory of Open Access Journals (Sweden)

    María Inés Marchesini

    Full Text Available Choloylglycine hydrolase (CGH, E.C. 3.5.1.24 is a conjugated bile salt hydrolase that catalyses the hydrolysis of the amide bond in conjugated bile acids. Bile salt hydrolases are expressed by gastrointestinal bacteria, and they presumably decrease the toxicity of host's conjugated bile salts. Brucella species are the causative agents of brucellosis, a disease affecting livestock and humans. CGH confers Brucella the ability to deconjugate and resist the antimicrobial action of bile salts, contributing to the establishment of a successful infection through the oral route in mice. Additionally, cgh-deletion mutant was also attenuated in intraperitoneally inoculated mice, which suggests that CGH may play a role during systemic infection other than hydrolyzing conjugated bile acids. To understand the role CGH plays in B. abortus virulence, we infected phagocytic and epithelial cells with a cgh-deletion mutant (Δcgh and found that it is defective in the internalization process. This defect along with the increased resistance of Δcgh to the antimicrobial action of polymyxin B, prompted an analysis of the cell envelope of this mutant. Two-dimensional electrophoretic profiles of Δcgh cell envelope-associated proteins showed an altered expression of Omp2b and different members of the Omp25/31 family. These results were confirmed by Western blot analysis with monoclonal antibodies. Altogether, the results indicate that Brucella CGH not only participates in deconjugation of bile salts but also affects overall membrane composition and host cell internalization.

  6. Synthesis, characterization and biological evaluation of bile acid-aromatic/heteroaromatic amides linked via amino acids as anti-cancer agents.

    Science.gov (United States)

    Agarwal, Devesh S; Anantaraju, Hasitha Shilpa; Sriram, Dharmarajan; Yogeeswari, Perumal; Nanjegowda, Shankara H; Mallu, P; Sakhuja, Rajeev

    2016-03-01

    A series of bile acid (Cholic acid and Deoxycholic acid) aryl/heteroaryl amides linked via α-amino acid were synthesized and tested against 3 human cancer cell-lines (HT29, MDAMB231, U87MG) and 1 human normal cell line (HEK293T). Some of the conjugates showed promising results to be new anticancer agents with good in vitro results. More specifically, Cholic acid derivatives 6a (1.35 μM), 6c (1.41 μM) and 6m (4.52 μM) possessing phenyl, benzothiazole and 4-methylphenyl groups showed fairly good activity against the breast cancer cell line with respect to Cisplatin (7.21 μM) and comparable with respect to Doxorubicin (1 μM), while 6e (2.49μM), 6i (2.46 μM) and 6m (1.62 μM) showed better activity against glioblastoma cancer cell line with respect to both Cisplatin (2.60 μM) and Doxorubicin (3.78 μM) drugs used as standards. Greater than 65% of the compounds were found to be safer on human normal cell line.

  7. Synthesis and Anti-tumor Activity of Novel Amide Derivatives of Ursolic Acid

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Ursolic acid was modified at C3 and C28 position to obtain fourteen derivatives including twelve novel compounds, and their chemical structures were characterized by IR, 1H NMR and MS. Cell growth inhibitory effects of the derivatives against Hela cell were evaluated by MTT assay. All these derivatives were found to have stronger cell growth inhibitory than their parent compound, ursolic acid. The derivatives with a substituted acetyl group at C3hydroxyl group show better activities than those with an unsubstituted hydroxyl group.

  8. sec-Butylpropylacetamide (SPD), a new amide derivative of valproic acid for the treatment of neuropathic and inflammatory pain.

    Science.gov (United States)

    Kaufmann, Dan; West, Peter J; Smith, Misty D; Yagen, Boris; Bialer, Meir; Devor, Marshall; White, H Steve; Brennan, K C

    2017-03-01

    Chronic pain is a multifactorial disease comprised of both inflammatory and neuropathic components that affect ∼20% of the world's population. sec-Butylpropylacetamide (SPD) is a novel amide analogue of valproic acid (VPA) previously shown to possess a broad spectrum of anticonvulsant activity. In this study, we defined the pharmacokinetic parameters of SPD in rat and mouse, and then evaluated its antinociceptive potential in neuropathic and acute inflammatory pain models. In the sciatic nerve ligation (SNL) model of neuropathic pain, SPD was equipotent to gabapentin and more potent than its parent compound VPA. SPD also showed either higher or equal potency to VPA in the formalin, carrageenan, and writhing tests of inflammatory pain. SPD showed no effects on compound action potential properties in a sciatic nerve preparation, suggesting that its mechanism of action is distinct from local anesthetics and membrane stabilizing drugs. SPD's activity in both neuropathic and inflammatory pain warrants its development as a potential broad-spectrum anti-nociceptive drug.

  9. Amino acid behavior in aqueous amide solutions: Temperature dependence of the L-phenylalanine–N,N-dimethylformamide interaction

    Energy Technology Data Exchange (ETDEWEB)

    Kustov, Andrey V., E-mail: kustov@isuct.ru

    2013-08-20

    Highlights: • Thermodynamics of amino acid solvation in aqueous DMF solutions was studied at 288–318 K. • The pair interaction parameters were compared with those for urea solutions. • For hydrophobic solutes enthalpies and entropies of interaction reveal strong temperature changes. • The relationship between the temperature dependence of solvation and solute–solute interactions was found. - Abstract: We have studied thermodynamics of the L-phenylalanine (Phe) pair interaction with denaturing agents – urea (U) and dimethylformamide (DMF) at 288–318 K. Our study does indicate that enthalpies and entropies of the Phe–U interaction reveal the anomalous temperature dependence which does not occur for DMF solutions. The anomalous Phe behavior in U solutions appears to be closely related to peculiarities of U hydration. One more result is in the fact that for hydrophobic solutes such as L-phenylalanine and substituted amides it is not justified to use the results obtained at 298 K for predicting the solute behavior at physiological temperatures.

  10. A proton wire and water channel revealed in the crystal structure of isatin hydrolase

    DEFF Research Database (Denmark)

    Bjerregaard-Andersen, Kaare; Sommer, Theis; Jensen, Jan Kristian;

    2014-01-01

    The high resolution crystal structures of isatin hydrolase from Labrenzia aggregata in the apo and the product state, are described. These are the first structures of a functionally characterized metal-dependent hydrolase of this fold. Isatin hydrolase converts isatin to isatinate and belongs to ...... of orthologous genes encoding isatin hydrolases within the prokaryotic kingdom. The isatin hydrolase orthologues found in human gut bacteria raise the question as to whether the indole-3-acetic acid degradation pathway is present in human gut flora....

  11. New co-crystal and salt form of sulfathiazole with carboxylic acid and amide

    Indian Academy of Sciences (India)

    Ranita Samanta; Shipra Kanaujia; C Malla Reddy

    2014-09-01

    One co-crystal and one salt of an antibacterial drug sulfathiazole with 4-aminobenzamide and 2,4-dinitrobenzoic acid have been synthesized. These new forms are characterized by single crystal X-ray diffraction, infrared spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In solid state, sulfathiazole preferentially adopts the imidine tautomeric form.

  12. Dianthosaponins G-I, triterpene saponins, an anthranilic acid amide glucoside and a flavonoid glycoside from the aerial parts of Dianthus japonicus and their cytotoxicity.

    Science.gov (United States)

    Kanehira, Yuka; Kawakami, Susumu; Sugimoto, Sachiko; Matsunami, Katsuyoshi; Otsuka, Hideaki

    2016-10-01

    Extensive isolation work on the 1-BuOH-soluble fraction of a MeOH extract of the aerial parts of Dianthus japonicus afforded three further triterpene glycosyl estsers, termed dianthosaponins G-I, an anthranilic acid amide glucoside and a C-glycosyl flavonoid along with one known triterpene saponin. Their structures were elucidated from spectroscopic evidence. The cytotoxicity of the isolated compounds toward A549 cells was evaluated.

  13. HPLC analysis of serotonin, tryptamine, tyramine, and the hydroxycinnamic acid amides of serotonin and tyramine in food vegetables.

    Science.gov (United States)

    Ly, Dalin; Kang, Kiyoon; Choi, Jang-Yeol; Ishihara, Atsushi; Back, Kyoungwhan; Lee, Seong-Gene

    2008-06-01

    Biogenic monoamines such as serotonin, tryptamine, and tyramine function as neurotransmitters and mitogenic factors in animals and are involved in flowering, morphogenesis, and protection from and adaptation to environmental changes in plants. In plants, serotonin and tyramine are conjugated to form phenolic compounds via thioester linkages during the synthesis of hydroxycinnamic acid amides, including p-coumaroylserotonin (CS), feruloylserotonin (FS), p-coumaroyltyramine (CT), and feruloyltyramine (FT). In this study, we determined the amounts of the biogenic monoamines CS, FS, CT, and FT in commonly consumed vegetables using high-performance liquid chromatography. Serotonin, tryptamine, and tyramine were detected in all vegetables tested. The serotonin levels ranged from 1.8 to 294 microg/g of dry weight, the tryptamine levels ranged from 0.8 to 372 microg/g of dry weight, and the tyramine levels ranged from 1.4 to 286 microg/g of dry weight. The highest serotonin and tryptamine contents were found in tomato and cherry tomato (140.3-222 microg/g of dry weight), while paprika and green pepper had higher tyramine contents than the other vegetables (286 and 141.5 microg/g of dry weight, respectively). Overall, the levels of CS, FS, CT, and FT ranged from 0.03 to 13.8 microg/g of dry weight, with green onion possessing the highest levels of CS (0.69 microg/g of dry weight), FT (1.99 microg/g of dry weight), and CT (13.85 microg/g of dry weight).

  14. Preparation of different amides via Ritter reaction from alcohols and nitriles in the presence of silica-bonded N- propyl sulphamic acid (SBNPSA) under solvent-free conditions

    Indian Academy of Sciences (India)

    Maryam-Sadat Shakeri; Hassan Tajik; Khodabakhsh Niknam

    2012-09-01

    A number of methods have been proposed for the modification of the Ritter reaction. However, many of these methods involve the use of strongly acidic conditions, stoichiometric amounts of reagents, harsh reaction conditions and extended reaction times. Therefore, the development of mild, efficient, convenient and benign reagents for the Ritter reaction is desirable. In this research, we have developed a clean and environmentally friendly protocol for the synthesis of amides by using different benzylic or tertiary alcohols and different nitriles in the presence of silica-bonded N- propyl sulphamic acid (SBNPSA) as catalyst under solvent-free conditions in high yields.

  15. Structures of D-amino-acid amidase complexed with L-phenylalanine and with L-phenylalanine amide: insight into the D-stereospecificity of D-amino-acid amidase from Ochrobactrum anthropi SV3.

    Science.gov (United States)

    Okazaki, Seiji; Suzuki, Atsuo; Mizushima, Tsunehiro; Komeda, Hidenobu; Asano, Yasuhisa; Yamane, Takashi

    2008-03-01

    The crystal structures of D-amino-acid amidase (DAA) from Ochrobactrum anthropi SV3 in complex with L-phenylalanine and with L-phenylalanine amide were determined at 2.3 and 2.2 A resolution, respectively. Comparison of the L-phenylalanine amide complex with the D-phenylalanine complex reveals that the D-stereospecificity of DAA might be achieved as a consequence of three structural factors: (i) the hydrophobic cavity in the region in which the hydrophobic side chain of the substrate is held, (ii) the spatial arrangement of Gln310 O and Glu114 O epsilon2 that fixes the amino N atom of the substrate and (iii) the existence of two cavities that keep the carboxyl/amide group of the substrate near or apart from Ser60 O gamma.

  16. Cholesterol-Lowering Potentials of Lactic Acid Bacteria Based on Bile-Salt Hydrolase Activity and Effect of Potent Strains on Cholesterol Metabolism In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Cheng-Chih Tsai

    2014-01-01

    Full Text Available This study collected different probiotic isolates from animal and plant sources to evaluate the bile-salt hydrolase activity of probiotics in vitro. The deconjugation potential of bile acid was determined using high-performance liquid chromatography. HepG2 cells were cultured with probiotic strains with high BSH activity. The triglyceride (TG and apolipoprotein B (apo B secretion by HepG2 cells were evaluated. Our results show that the BSH activity and bile-acid deconjugation abilities of Pediococcus acidilactici NBHK002, Bifidobacterium adolescentis NBHK006, Lactobacillus rhamnosus NBHK007, and Lactobacillus acidophilus NBHK008 were higher than those of the other probiotic strains. The cholesterol concentration in cholesterol micelles was reduced within 24 h. NBHK007 reduced the TG secretion by 100% after 48 h of incubation. NBHK002, NBHK006, and NBHK007 could reduce apo B secretion by 33%, 38%, and 39%, respectively, after 24 h of incubation. The product PROBIO S-23 produced a greater decrease in the total concentration of cholesterol, low-density lipoprotein, TG, and thiobarbituric acid reactive substance in the serum or livers of hamsters with hypercholesterolemia compared with that of hamsters fed with a high-fat and high-cholesterol diet. These results show that the three probiotic strains of lactic acid bacteria are better candidates for reducing the risk of cardiovascular disease.

  17. Electrospun Scaffolds from Low Molecular Weight Poly(ester amides Based on Glycolic Acid, Adipic Acid and Odd or Even Diamines

    Directory of Open Access Journals (Sweden)

    Sara Keiko Murase

    2015-05-01

    Full Text Available Electrospinning of regular poly(ester amides (PEAs constituted by glycolic acid, adipic acid and diamines with five and six carbon atoms has been carried out. Selected PEAs were constituted by natural origin products and could be easily prepared by a polycondensation method that avoids tedious protection and deprotection steps usually required for obtaining polymers with a regular sequence. Nevertheless, the synthesis had some limitations that mainly concerned the final low/moderate molecular weight that could be attained. Therefore, it was considered interesting to evaluate if electrospun scaffolds could still be prepared taking also advantage of the capability of PEAs to establish intermolecular hydrogen bonds. Results indicated that the crucial factor was the control of polymer concentration in the electrospun solution, being necessary that this concentration was higher than 40% (w/v. The PEA with the lowest molecular weight (Mw close to 8000 g/mol was the most appropriate to obtain electrospun samples with a circular cross-section since higher molecular sized polymers show solvent retention problems derived from the high viscosity of the electrospun solution that rendered ribbon-like morphologies after the impact of fibers into the collector. The studied PEAs were semicrystalline and biodegradable, as demonstrated by calorimetric and degradation studies. Furthermore, the new scaffolds were able to encapsulate drugs with anti-inflammatory and bacteriostatic activities like ketoprofen. The corresponding release and bactericide activity was evaluated in different media and against different bacteria. Finally, biocompatibility was demonstrated using both fibroblast and epithelial cell lines.

  18. Development and validation of an LCMS method to determine the pharmacokinetic profiles of caffeic acid phenethyl amide and caffeic acid phenethyl ester in male Sprague-Dawley rats.

    Science.gov (United States)

    Yang, John; Bowman, Phillip D; Kerwin, Sean M; Stavchansky, Salomon

    2014-02-01

    A validated LCMS method was developed for the quantitative determination of caffeic acid phenethyl amide (CAPA) and caffeic acid phenethyl ester (CAPE) from rat plasma. Separation was achieved using a reverse-phase C12 HPLC column (150 × 2.00 mm, 4 µm) with gradient elution running water (A) and acetonitrile (B). Mass spectrometry was performed with electrospray ionization in negative mode. This method was used to determine the pharmacokinetic profiles of CAPA and CAPE in male Sprague-Dawley rats following intravenous bolus administration of 5, 10 and 20 mg/kg of CAPA and 20 mg/kg of CAPE. The pharmacokinetic analysis suggests the lack of dose proportionality in the dose range of 5-20 mg/kg of CAPA. Total clearance values for CAPA ranged from 45 to 156 mL/min and decreased with increasing dose of CAPA. The volume of distribution for CAPA ranged from 17,750 to 52,420 mL, decreasing with increasing dose. The elimination half-life for CAPA ranged from 243.1 to 295.8 min and no statistically significant differences were observed between dose groups in the range of 5-20 mg/kg (p > 0.05). The elimination half-life for CAPE was found to be 92.26 min.

  19. [Synthetic transformations of higher terpenoids. XXX. Synthesis and cytotoxic activity of betulonic acid amides with a piperidine or pyrrolidine nitroxide moiety].

    Science.gov (United States)

    Antimonova, A N; Petrenko, N I; Shults, E E; Polienko, Iu F; Shakirov, M M; Irtegova, I G; Pokrovskiĭ, M A; Sherman, K M; Grigor'ev, I A; Pokrovskiĭ, A G; Tolstikov, G A

    2013-01-01

    The reaction of betulonic acid chloride with 4-amino-2,2,6,6-tetramethylpeperidine-1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidine-1-oxyl and 3-aminomethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl gave corresponding triterpenoid amides. It was found that new derivatives exhibit cytotoxic activity against tumor cells CEM-13, U-937, MT-4. CCID50 value for most activity compound--N-[3-oxolup-20(29)-en-30-yl]-(2,2,6,6-tetramethylpiperidine-4-yl)-1-oxyl--was 5.7-33.1 microM.

  20. Cyanuric acid hydrolase from Azorhizobium caulinodans ORS 571: crystal structure and insights into a new class of Ser-Lys dyad proteins.

    Directory of Open Access Journals (Sweden)

    Seunghee Cho

    Full Text Available Cyanuric acid hydrolase (CAH catalyzes the hydrolytic ring-opening of cyanuric acid (2,4,6-trihydroxy-1,3,5-triazine, an intermediate in s-triazine bacterial degradation and a by-product from disinfection with trichloroisocyanuric acid. In the present study, an X-ray crystal structure of the CAH-barbituric acid inhibitor complex from Azorhizobium caulinodans ORS 571 has been determined at 2.7 Å resolution. The CAH protein fold consists of three structurally homologous domains forming a β-barrel-like structure with external α-helices that result in a three-fold symmetry, a dominant feature of the structure and active site that mirrors the three-fold symmetrical shape of the substrate cyanuric acid. The active site structure of CAH is similar to that of the recently determined AtzD with three pairs of active site Ser-Lys dyads. In order to determine the role of each Ser-Lys dyad in catalysis, a mutational study using a highly sensitive, enzyme-coupled assay was conducted. The 10⁹-fold loss of activity by the S226A mutant was at least ten times lower than that of the S79A and S333A mutants. In addition, bioinformatics analysis revealed the Ser226/Lys156 dyad as the only absolutely conserved dyad in the CAH/barbiturase family. These data suggest that Lys156 activates the Ser226 nucleophile which can then attack the substrate carbonyl. Our combination of structural, mutational, and bioinformatics analyses differentiates this study and provides experimental data for mechanistic insights into this unique protein family.

  1. Inhibitors of HIV-1 maturation: Development of structure-activity relationship for C-28 amides based on C-3 benzoic acid-modified triterpenoids.

    Science.gov (United States)

    Swidorski, Jacob J; Liu, Zheng; Sit, Sing-Yuen; Chen, Jie; Chen, Yan; Sin, Ny; Venables, Brian L; Parker, Dawn D; Nowicka-Sans, Beata; Terry, Brian J; Protack, Tricia; Rahematpura, Sandhya; Hanumegowda, Umesh; Jenkins, Susan; Krystal, Mark; Dicker, Ira B; Meanwell, Nicholas A; Regueiro-Ren, Alicia

    2016-04-15

    We have recently reported on the discovery of a C-3 benzoic acid (1) as a suitable replacement for the dimethyl succinate side chain of bevirimat (2), an HIV-1 maturation inhibitor that reached Phase II clinical trials before being discontinued. Recent SAR studies aimed at improving the antiviral properties of 2 have shown that the benzoic acid moiety conferred topographical constraint to the pharmacophore and was associated with a lower shift in potency in the presence of human serum albumin. In this manuscript, we describe efforts to improve the polymorphic coverage of the C-3 benzoic acid chemotype through modifications at the C-28 position of the triterpenoid core. The dimethylaminoethyl amides 17 and 23 delivered improved potency toward bevirimat-resistant viruses while increasing C24 in rat oral PK studies.

  2. SYNTHESIS OF MONO CARBAMOYL AMIDE OF SQUARIC ACID%氨甲酰类氮氧方酸的合成研究

    Institute of Scientific and Technical Information of China (English)

    李鸿波; 李聚才; 陈益钊

    2000-01-01

    A kind of mono-substituted squaric amide——mono carbamoyl amide of squaric acid 3 (MCASAQ) was prepared by the condensation of squaric acid (SQ) with urea or its derivatives in water. MCASAQs (3) may have some physiological activity for the ureido was brought into them. Meanwhile, the reaction of SQ with arylureain water provided a new route to the preparation of Narylnitrogenoxosquaric acids.%以水为介质,方酸与脲及其衍生物顺利发生脱水缩合,合成了一类方酸单酰胺化合物——氨甲酰类氮氧方酸3.方酸与芳基脲于水中的反应为N-芳基氮氧方酸的制备提供了一条新途径

  3. Synthesis and characterization of heat-resistant and soluble poly(amide-imide)s from unsymmetrical dicarboxylic acid containing 2-(triphenyl phosphoranylidene) moiety and various aromatic diamines

    Indian Academy of Sciences (India)

    Seema Agrawal; Anudeep Kumar Narula

    2015-04-01

    An unsymmetrical and non-coplaner heterocyclic phosphorus containing dicarboxylic acid monomer, (DCA-3) is successfully synthesized with high purity. A series of novel aromatic poly(amide-imide)s having ether or/sulphur or/fluorine or/phosphorus containing phenyl moieties in their backbone are then prepared via a direct phosphorylation polycondensation of synthesized dicarboxylic acid with various aromatic diamines. Chemical structures of DCA-3 as well as resulting polymers are confirmed by FT-IR, NMR spectroscopic techniques and elemental analysis. These polymers are readily soluble in a variety of aprotic polar solvents such as NMP, DMSO, DMAc and DMF, etc. UV spectra showed that all poy(amide-imide)s films exhibit high optical transparency. In addition, the glass transition temperatures (Tg) of these polymers were determined by differential scanning calorimetry and found in the range 271–346°C. Furthermore, thermogravimetric analysis of these polymers showed good thermal stability, 10% weight loss at temperature in excess of 538°C and char yield at 700°C in nitrogen ranging from 68 to 79%. From wide-angle X-ray diffraction experiments, all polymers showed amorphous behaviour.

  4. Salicylic acid-independent ENHANCED DISEASE SUSCEPTIBILITY1 signaling in Arabidopsis immunity and cell death is regulated by the monooxygenase FMO1 and the Nudix hydrolase NUDT7.

    Science.gov (United States)

    Bartsch, Michael; Gobbato, Enrico; Bednarek, Pawel; Debey, Svenja; Schultze, Joachim L; Bautor, Jaqueline; Parker, Jane E

    2006-04-01

    Arabidopsis thaliana ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) controls defense activation and programmed cell death conditioned by intracellular Toll-related immune receptors that recognize specific pathogen effectors. EDS1 is also needed for basal resistance to invasive pathogens by restricting the progression of disease. In both responses, EDS1, assisted by its interacting partner, PHYTOALEXIN-DEFICIENT4 (PAD4), regulates accumulation of the phenolic defense molecule salicylic acid (SA) and other as yet unidentified signal intermediates. An Arabidopsis whole genome microarray experiment was designed to identify genes whose expression depends on EDS1 and PAD4, irrespective of local SA accumulation, and potential candidates of an SA-independent branch of EDS1 defense were found. We define two new immune regulators through analysis of corresponding Arabidopsis loss-of-function insertion mutants. FLAVIN-DEPENDENT MONOOXYGENASE1 (FMO1) positively regulates the EDS1 pathway, and one member (NUDT7) of a family of cytosolic Nudix hydrolases exerts negative control of EDS1 signaling. Analysis of fmo1 and nudt7 mutants alone or in combination with sid2-1, a mutation that severely depletes pathogen-induced SA production, points to SA-independent functions of FMO1 and NUDT7 in EDS1-conditioned disease resistance and cell death. We find instead that SA antagonizes initiation of cell death and stunting of growth in nudt7 mutants.

  5. Biological activity of novel N-substituted amides of endo-3-(3-methylthio-1,2,4-triazol-5-yl)bicyclo[2.2.1]hept-5-ene-2-carboxylic acid and N-substituted amides of 1-(5-methylthio-1,2,4-triazol-3-yl)cyclohexane-2-carboxylic acids.

    Science.gov (United States)

    Pachuta-Stec, Anna; Kosikowska, Urszula; Chodkowska, Anna; Pitucha, Monika; Malm, Anna; Jagiełło-Wójtowicz, Ewa

    2012-01-01

    N-Substituted amides of endo-3-(3-methylthio-1,2,4-triazol-5-yl)bicyclo[2.2.1]hept-5-ene-2-carboxylic acid and 1-(5-methylthio-1,2,4-triazol-3-yl)cyclohexane-2-carboxylic acid were prepared by the condensation reaction of endo-S-methyl-N1-(bicyclo[2.2.1]hept-5-ene-2,3-dicarbonyl)isothiosemicarbazide and S-methyl-N1-(cyclohexane-2,3-dicarbonyl)isothiosemicarbazide with primary amines. The synthesized compounds were screened for their microbiological and pharmacological activities.

  6. Amino acid-functionalized multi-walled carbon nanotubes for improving compatibility with chiral poly(amide-ester-imide) containing L-phenylalanine and L-tyrosine linkages

    Energy Technology Data Exchange (ETDEWEB)

    Abdolmaleki, Amir, E-mail: abdolmaleki@cc.iut.ac.ir [Organic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of); Nanotechnology and Advanced Materials Institute, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of); Mallakpour, Shadpour, E-mail: mallakpour84@alumni.ufl.edu [Organic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of); Nanotechnology and Advanced Materials Institute, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of); Borandeh, Sedigheh [Organic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of)

    2013-12-15

    Amino acid functionalized multi-walled carbon nanotubes (f-MWCNTs)/poly(amide-ester-imide) (PAEI) composites were fabricated by solution mixing method. Proper functionalization and mixing strategy of MWCNTs provides the best opportunity for better distribution and bonding of nanoparticles to the polymer matrix. MWCNTs have been chemically modified with L-phenylalanine to improve their compatibility with L-phenylalanine based PAEI. Field emission scanning electron microscopy micrographs of composite revealed that f-MWCNTs made a good interaction with polymer chains by wrapping the polymer around them, and transmission electron microscopy results confirmed well dispersion with nano size of f-MWCNTs in the polymer matrix. In addition, thermal analysis showed good enhancement in thermal properties of composites compared to pure polymer. Thermal stability of the composites containing f-MWCNTs was enhanced due to their good dispersion and improved interfacial interaction between the amino acid based PAEI matrix and f-MWCNTs.

  7. Amino acid-functionalized multi-walled carbon nanotubes for improving compatibility with chiral poly(amide-ester-imide) containing L-phenylalanine and L-tyrosine linkages

    Science.gov (United States)

    Abdolmaleki, Amir; Mallakpour, Shadpour; Borandeh, Sedigheh

    2013-12-01

    Amino acid functionalized multi-walled carbon nanotubes (f-MWCNTs)/poly(amide-ester-imide) (PAEI) composites were fabricated by solution mixing method. Proper functionalization and mixing strategy of MWCNTs provides the best opportunity for better distribution and bonding of nanoparticles to the polymer matrix. MWCNTs have been chemically modified with L-phenylalanine to improve their compatibility with L-phenylalanine based PAEI. Field emission scanning electron microscopy micrographs of composite revealed that f-MWCNTs made a good interaction with polymer chains by wrapping the polymer around them, and transmission electron microscopy results confirmed well dispersion with nano size of f-MWCNTs in the polymer matrix. In addition, thermal analysis showed good enhancement in thermal properties of composites compared to pure polymer. Thermal stability of the composites containing f-MWCNTs was enhanced due to their good dispersion and improved interfacial interaction between the amino acid based PAEI matrix and f-MWCNTs.

  8. Spectral studies of dimeric copper(II) complexes of acid amide derivatives as models for type III copper enzymes

    Science.gov (United States)

    Garg, Bhagwan S.; Nandan Kumar, Deo; Sarbhai, Meenu; Reddy, Malladi J.

    2003-10-01

    Dimeric (hydrated and anhydrated) complexes of Cu(II) with N, N'-bis(3-carboxy-1-oxo-2-prop-2-enyl)ethylenediamine(BCOPENH 2, A) and N, N'-bis(2-carboxy-1-oxo-phenylenyl)ethylenediamine(BCOPHENH 2, B) have been prepared and characterised by elemental analysis, magnetic susceptibility measurements, EPR, thermal and spectral (IR, UV/Vis) studies. EPR parameters and magnetic behaviour indicates that the complexes are antiferromagnetic in nature and most likely adopt the typical carboxylate cage structure. Interesting amide bonding patterns have been observed and various EPR parameters have been evaluated on the basis of these studies, tentative probable structures of the complexes have been proposed.

  9. Hydrogen bonding in cyclic imides and amide carboxylic acid derivatives from the facile reaction of cis-cyclohexane-1,2-carboxylic anhydride with o- and p-anisidine and m- and p-aminobenzoic acids.

    Science.gov (United States)

    Smith, Graham; Wermuth, Urs D

    2012-09-01

    The structures of the open-chain amide carboxylic acid rac-cis-2-[(2-methoxyphenyl)carbamoyl]cyclohexane-1-carboxylic acid, C(15)H(19)NO(4), (I), and the cyclic imides rac-cis-2-(4-methoxyphenyl)-3a,4,5,6,7,7a-hexahydroisoindole-1,3-dione, C(15)H(17)NO(3), (II), chiral cis-3-(1,3-dioxo-3a,4,5,6,7,7a-hexahydroisoindol-2-yl)benzoic acid, C(15)H(15)NO(4), (III), and rac-cis-4-(1,3-dioxo-3a,4,5,6,7,7a-hexahydroisoindol-2-yl)benzoic acid monohydrate, C(15)H(15)NO(4)·H(2)O, (IV), are reported. In the amide acid (I), the phenylcarbamoyl group is essentially planar [maximum deviation from the least-squares plane = 0.060 (1) Å for the amide O atom] and the molecules form discrete centrosymmetric dimers through intermolecular cyclic carboxy-carboxy O-H···O hydrogen-bonding interactions [graph-set notation R(2)(2)(8)]. The cyclic imides (II)-(IV) are conformationally similar, with comparable benzene ring rotations about the imide N-C(ar) bond [dihedral angles between the benzene and isoindole rings = 51.55 (7)° in (II), 59.22 (12)° in (III) and 51.99 (14)° in (IV)]. Unlike (II), in which only weak intermolecular C-H···O(imide) hydrogen bonding is present, the crystal packing of imides (III) and (IV) shows strong intermolecular carboxylic acid O-H···O hydrogen-bonding associations. With (III), these involve imide O-atom acceptors, giving one-dimensional zigzag chains [graph-set C(9)], while with the monohydrate (IV), the hydrogen bond involves the partially disordered water molecule which also bridges molecules through both imide and carboxy O-atom acceptors in a cyclic R(4)(4)(12) association, giving a two-dimensional sheet structure. The structures reported here expand the structural database for compounds of this series formed from the facile reaction of cis-cyclohexane-1,2-dicarboxylic anhydride with substituted anilines, in which there is a much larger incidence of cyclic imides compared to amide carboxylic acids.

  10. Synthesis, Antifungal Activity and Structure-Activity Relationships of Novel 3-(Difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic Acid Amides

    Directory of Open Access Journals (Sweden)

    Shijie Du

    2015-05-01

    Full Text Available A series of novel 3-(difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid amides were synthesized and their activities were tested against seven phytopathogenic fungi by an in vitro mycelia growth inhibition assay. Most of them displayed moderate to excellent activities. Among them N-(2-(5-bromo-1H-indazol-1-ylphenyl-3-(difluoro-methyl-1-methyl-1H-pyrazole-4-carboxamide (9m exhibited higher antifungal activity against the seven phytopathogenic fungi than boscalid. Topomer CoMFA was employed to develop a three-dimensional quantitative structure-activity relationship model for the compounds. In molecular docking, the carbonyl oxygen atom of 9m could form hydrogen bonds towards the hydroxyl of TYR58 and TRP173 on SDH.

  11. Synthesis of Caffeic Acid Amides Bearing 2,3,4,5-Tetra-hydrobenzo[b][1,4]dioxocine Moieties and Their Biological Evaluation as Antitumor Agents

    Directory of Open Access Journals (Sweden)

    Ji-Wen Yuan

    2014-06-01

    Full Text Available A series of caffeic acid amides D1-D17 bearing 2,3,4,5-tetrahydrobenzo-[b][1,4]dioxocine units has been synthesized and their biological activities evaluated for potential antiproliferative and EGFR inhibitory activity. Of all the compounds studied, compound D9 showed the most potent inhibitory activity (IC50 = 0.79 μM for HepG2 and IC50 = 0.36 μM for EGFR. The structures of compounds were confirmed by 1H-NMR, ESI-MS and elemental analysis. Among all, the structure of compound D9 ((E-N-(4-ethoxyphenyl-3-(2,3,4,5-tetrahydrobenzo[b][1,4]dioxocin-8-ylacrylamide was also determined by single-crystal X-ray diffraction analysis. Compound D9 was found to be a potential antitumor agent according to biological activity, molecular docking, apoptosis assay and inhibition of HepG2.

  12. Grafting of 4-(2,4,6-Trimethylphenoxybenzoyl onto Single-Walled Carbon Nanotubes in Poly(phosphoric acid via Amide Function

    Directory of Open Access Journals (Sweden)

    Tan Loon-Seng

    2009-01-01

    Full Text Available Abstract Single-walled carbon nanotubes (SWCNTs, which were commercial grade containing 60–70 wt% impurity, were treated in a mild poly(phosphoric acid (PPA. The purity of PPA treated SWCNTs was greatly improved with or without little damage to SWCNTs framework and stable crystalline carbon particles. An amide model compound, 4-(2,4,6-trimethylphenoxybenzamide (TMPBA, was reacted with SWCNTs in PPA with additional phosphorous pentoxide as “direct” Friedel–Crafts acylation reaction to afford TMPBA functionalized SWCNTs. All evidences obtained from Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, scanning electron microcopy, and transmission electron microscopy strongly supported that the functionalization of SWCNTs with benzamide was indeed feasible.

  13. Bioactivation of a dihydropyrazole-1-carboxylic acid-(4-chlorophenyl amide) scaffold to a putative p-chlorophenyl isocyanate in rat liver microsomes and in vivo in rats.

    Science.gov (United States)

    Chen, Hao; Zhang, Yanhua; Edmunds, Jeremy; Bigge, Christopher; Mutlib, Abdul

    2008-05-01

    Compound I (4,5-dihydropyrazole-1,5-dicarboxylic acid-1-[(4-chlorophenyl)-amide] 5-[(2-oxo-2 H-[1,3']bipyridinyl-6'-yl)-amide] was found to undergo metabolic activation in rat liver microsomes in the presence of NADPH. A reactive intermediate, postulated to be p-chlorophenyl isocyanate (CPIC), was trapped by GSH in vitro and characterized by liquid chromatography tandem mass spectrometry (LC/MS/MS). Subsequently, the structure of the GSH conjugate was confirmed by a comparison with a synthetic standard. The GSH conjugate was also found in the bile of rats that received an oral dose (10 mg/kg) of compound I. Further analyses of rat bile and urine using online electrochemical derivatization coupled to LC/MS demonstrated the presence of p-chlorophenyl aniline (CPA), a hydrolytic product of the intermediate isocyanate. This provided further evidence for the potential existence of CPIC. Approximately 7% of the dose was accounted by the products of CPIC, which included the GSH conjugate and CPA excreted in bile and urine. Multiple rat cytochrome P450 enzymes, including P450 1A, P450 2C, and P450 3A, appeared to be responsible for the activation of compound I to CPIC. The activation kinetics of compound I to CPIC in male rat liver microsomes exhibited a biphasic profile, indicative of at least two contributing P450 enzymes. One enzyme showed a small value of K m at 42 microM and a low V max of 66 pmol min (-1) mg (-1), while the other exhibited a large value of K m at 148 microM and a high V max of 1200 pmol min (-1) mg (-1). The formation of a putative CPIC intermediate, a carbamoylating species known to be capable of covalent binding to macromolecules, suggests a potential liability associated with the compound, particularly the dihydropyrazole-1-carboxylic acid-(4-chlorophenyl amide) scaffold, which appears to be responsible for the generation of CPIC. The mechanism of bioactivation to the putative CPIC is postulated to involve an initial P450-mediated hydroxylation of

  14. Catalytic synthesis of amides via aldoximes rearrangement.

    Science.gov (United States)

    Crochet, Pascale; Cadierno, Victorio

    2015-02-14

    Amide bond formation reactions are among the most important transformations in organic chemistry because of the widespread occurrence of amides in pharmaceuticals, natural products and biologically active compounds. The Beckmann rearrangement is a well-known method to generate secondary amides from ketoximes. However, under the acidic conditions commonly employed, aldoximes RHC=NOH rarely rearrange into the corresponding primary amides RC(=O)NH2. In recent years, it was demonstrated that this atom-economical transformation can be carried out efficiently and selectively with the help of metal catalysts. Several homogeneous and heterogenous systems have been described. In addition, protocols offering the option to generate the aldoximes in situ from the corresponding aldehydes and hydroxylamine, or even from alcohols, have also been developed, as well as a series of tandem processes allowing the access to N-substituted amide products. In this Feature article a comprehensive overview of the advances achieved in this particular research area is presented.

  15. Pre-treatment with new kynurenic acid amide dose-dependently prevents the nitroglycerine-induced neuronal activation and sensitization in cervical part of trigemino-cervical complex.

    Science.gov (United States)

    Fejes-Szabó, Annamária; Bohár, Zsuzsanna; Vámos, Enikő; Nagy-Grócz, Gábor; Tar, Lilla; Veres, Gábor; Zádori, Dénes; Szentirmai, Márton; Tajti, János; Szatmári, István; Fülöp, Ferenc; Toldi, József; Párdutz, Árpád; Vécsei, László

    2014-07-01

    The systemic administration of nitroglycerine induces attacks in migraineurs and is able to activate and sensitize the trigeminal system in animals involving glutamate and α7-nicotinic acetylcholine receptors, among others. Kynurenic acid is one of the endogenous glutamate receptor antagonists, and exerts inhibitory action on the α7-nicotinic acetylcholine receptors. Since kynurenic acid penetrates the blood-brain barrier poorly, therefore a newly synthesized kynurenic acid amide, N-(2-N-pyrrolidinylethyl)-4-oxo-1H-quinoline-2-carboxamide hydrochloride (KYNAa) was used with such a side-chain substitution to facilitate brain penetration in our study. We evaluated its modulatory effect on kynurenic acid concentration in the cervical part of trigemino-cervical complex (C1-C2) and in the model of nitroglycerine-induced trigeminal activation using male Sprague-Dawley rats. One hour after 1 mmol/kg bodyweight KYNAa administration, the kynurenic acid level increased significantly in C1-C2, which returned to the basal level at 300 min measured by high-performance liquid chromatography. KYNAa pre-treatment had dose-dependent, mitigating action on nitroglycerine-induced decrease in calcitonin gene-related peptide and increase in c-Fos, neuronal nitric oxide synthase and calmodulin-dependent protein kinase II alpha expression in the C1-C2. KYNAa also mitigated the behavioural changes after nitroglycerine. Thus, in this model KYNAa is able to modulate in a dose-dependent manner the changes in neurochemical markers of activation and sensitization of the trigeminal system directly and indirectly--via forming kynurenic acid, possibly acting on peripheral and central glutamate or α7-nicotinic acetylcholine receptors. These results suggest that application of kynurenic acid derivatives could be a useful therapeutic strategy in migraine headache in the future with a different mechanism of action.

  16. Bacterial CS2 hydrolases from Acidithiobacillus thiooxidans strains are homologous to the archaeal catenane CS2 hydrolase.

    Science.gov (United States)

    Smeulders, Marjan J; Pol, Arjan; Venselaar, Hanka; Barends, Thomas R M; Hermans, John; Jetten, Mike S M; Op den Camp, Huub J M

    2013-09-01

    Carbon disulfide (CS(2)) and carbonyl sulfide (COS) are important in the global sulfur cycle, and CS(2) is used as a solvent in the viscose industry. These compounds can be converted by sulfur-oxidizing bacteria, such as Acidithiobacillus thiooxidans species, to carbon dioxide (CO(2)) and hydrogen sulfide (H2S), a property used in industrial biofiltration of CS(2)-polluted airstreams. We report on the mechanism of bacterial CS(2) conversion in the extremely acidophilic A. thiooxidans strains S1p and G8. The bacterial CS(2) hydrolases were highly abundant. They were purified and found to be homologous to the only other described (archaeal) CS(2) hydrolase from Acidianus strain A1-3, which forms a catenane of two interlocked rings. The enzymes cluster in a group of β-carbonic anhydrase (β-CA) homologues that may comprise a subclass of CS(2) hydrolases within the β-CA family. Unlike CAs, the CS(2) hydrolases did not hydrate CO(2) but converted CS(2) and COS with H(2)O to H(2)S and CO(2). The CS(2) hydrolases of A. thiooxidans strains G8, 2Bp, Sts 4-3, and BBW1, like the CS(2) hydrolase of Acidianus strain A1-3, exist as both octamers and hexadecamers in solution. The CS(2) hydrolase of A. thiooxidans strain S1p forms only octamers. Structure models of the A. thiooxidans CS(2) hydrolases based on the structure of Acidianus strain A1-3 CS(2) hydrolase suggest that the A. thiooxidans strain G8 CS(2) hydrolase may also form a catenane. In the A. thiooxidans strain S1p enzyme, two insertions (positions 26 and 27 [PD] and positions 56 to 61 [TPAGGG]) and a nine-amino-acid-longer C-terminal tail may prevent catenane formation.

  17. Chiral bio-nanocomposites based on thermally stable poly(amide-imide) having phenylalanine linkages and reactive organoclay containing tyrosine amino acid.

    Science.gov (United States)

    Mallakpour, Shadpour; Dinari, Mohammad

    2013-03-01

    Montmorillonite clay modified with the bio-active trifunctional L-tyrosine amino acid salt was used as a reactive organoclay (OC) for the preparation of poly(amide-imide) (PAI)/OC hybrid films. One of the functional groups of the L-tyrosine as the swelling agent formed an ionic bond with the negatively charged silicates, whereas the remaining functional groups were available for further reaction with polymer matrix. The soluble PAI with amine end groups including phenylalanine amino acid was synthesised under green condition using molten tetra-butylammonium bromide by direct polymerization reaction of chiral diacid and 2-(3,5-diaminophenyl)benzimidazole. PAI/OC bio-nanocomposites films containing different contents of OC were prepared via solution intercalation method through blending of OC with the PAI solution. X-ray diffraction and transmission electron microscopy revealed that the dispersion of silicate layers in the PAI created an exfoliated structure as a result of using the trifunctional groups of the swelling agent. The structure and thermal behavior of the synthesised materials were characterized by a range of methods, including X-ray diffraction, Fourier transform infrared spectroscopy, (1)H-NMR, electron microscopy, elemental and thermogravimetric analysis techniques. Thermogravimetric analysis results indicated that the addition of OC into the PAI matrix was increased in the thermal decomposition temperatures of the resulted bio-nanocomposites.

  18. Anticonvulsant and antinociceptive activity of new amides derived from 3-phenyl-2,5-dioxo-pyrrolidine-1-yl-acetic acid in mice.

    Science.gov (United States)

    Rapacz, Anna; Obniska, Jolanta; Wiklik-Poudel, Beata; Rybka, Sabina; Sałat, Kinga; Filipek, Barbara

    2016-06-15

    The aim of the present experiments was to examine the anticonvulsant and antinociceptive activity of five new amides derived from 3-phenyl-2,5-dioxo-pyrrolidine-1-yl-acetic acid in animal models of seizures and pain. The antiseizure activity was investigated in three acute models of seizures, namely, the maximal electroshock (MES), the subcutaneous pentylenetetrazole (scPTZ), and 6Hz psychomotor seizure tests in mice. The antinociceptive properties were estimated in the formalin model of tonic pain, and in the oxaliplatin-induced neuropathic pain model in mice. Considering drug safety evaluation, acute neurological toxicity was determined in the rotarod test. Three tested compounds (3, 4, and 7) displayed a broad spectrum of anticonvulsant activity and showed better protective indices than those obtained for MES/scPTZ/6Hz active reference drug - valproic acid. Furthermore, three compounds (3, 4, and 6) demonstrated a significant antinociceptive effect in the formalin test, as well as antiallodynic activity in the oxaliplatin-induced neuropathic pain model. Among the tested agents, compounds 3 and 4 displayed not only antiseizure properties, but also collateral prominent analgesic properties. The in vitro binding study indicated that the plausible mechanism of action of chosen compound (4) was the influence on neuronal voltage-sensitive sodium (site 2) and L-type calcium channels.

  19. Enantioselective synthesis of α-oxy amides via Umpolung amide synthesis.

    Science.gov (United States)

    Leighty, Matthew W; Shen, Bo; Johnston, Jeffrey N

    2012-09-19

    α-Oxy amides are prepared through enantioselective synthesis using a sequence beginning with a Henry addition of bromonitromethane to aldehydes and finishing with Umpolung Amide Synthesis (UmAS). Key to high enantioselection is the finding that ortho-iodo benzoic acid salts of the chiral copper(II) bis(oxazoline) catalyst deliver both diastereomers of the Henry adduct with high enantiomeric excess, homochiral at the oxygen-bearing carbon. Overall, this approach to α-oxy amides provides an innovative complement to alternatives that focus almost entirely on the enantioselective synthesis of α-oxy carboxylic acids.

  20. Facile Synthesis of Monofluoro y-Lactones and Pyrrolidine Derivatives via Electrophilic Fluorination of Allenoic Acids and Amides

    Institute of Scientific and Technical Information of China (English)

    CUl Haifeng; CHAI Zhuo; ZHAO Gang; ZHU Shizheng

    2009-01-01

    A convenient method to synthesize a series of monofluoro γ-1actones and pyrrolidine derivatives in moderate to good yields via the electrophilic fluorination of y-allenoic acids and tosylamides using Selectfluor was developed.

  1. Production of novel antioxidative phenolic amides through heterologous expression of the plant’s chlorogenic acid biosynthesis genes in yeast

    NARCIS (Netherlands)

    Moglia, A.; Comino, C.; Lanteri, S.; Vos, de C.H.; Waard, de P.; Beek, van T.A.; Goitre, L.; Retta, S.F.; Beekwilder, M.J.

    2010-01-01

    Phenolic esters like chlorogenic acid play an important role in therapeutic properties of many plant extracts. We aimed to produce phenolic esters in baker’s yeast, by expressing tobacco 4CL and globe artichoke HCT. Indeed yeast produced phenolic esters. However, the primary product was identified a

  2. Sequence of the bphD gene encoding 2-hydroxy-6-oxo-(phenyl/chlorophenyl)hexa-2,4-dienoic acid (HOP/cPDA) hydrolase involved in the biphenyl/polychlorinated biphenyl degradation pathway in Comamonas testosteroni: evidence suggesting involvement of Ser112 in catalytic activity.

    Science.gov (United States)

    Ahmad, D; Fraser, J; Sylvestre, M; Larose, A; Khan, A; Bergeron, J; Juteau, J M; Sondossi, M

    1995-04-14

    The nucleotide sequence of bphD, encoding 2-hydroxy-6-oxo-(phenyl/chlorophenyl)hexa-2,4-dienoic acid hydrolase involved in the biphenyl/polychlorinated biphenyl degradation pathway of Comamonas testosteroni strain B-356, was determined. Comparison of the deduced amino-acid sequence with published sequences led to the identification of a 'lipase box', containing a consensus pentapeptide sequence GlyXaaSerXaaGly. This suggested that the mechanism of action of this enzyme may involve an Asp-Ser-His catalytic triad similar to that of classical lipases and serine hydrolases. Further biochemical and genetic evidence for the active-site involvement of Ser112 was obtained by showing that a semipurified enzyme was inhibited by PMSF, a classic inhibitor of serine hydrolases, and by site-directed Ser112-->Ala mutagenesis.

  3. 新型甘草次酸酰胺杂环衍生物的合成及其抗结核活性%Synthesis of Novel 18β-Glycyrrhetinic Acid Derivatives Containing Heterocycle Amides and Their Antituberculosis Activities

    Institute of Scientific and Technical Information of China (English)

    陈凑喜; 李学强; 冯雷; 李天才; 周学章; 代静; 孙健

    2012-01-01

    以18β-甘草次酸为原料,经过多步酰胺化反应合成了14个含不同杂环的新型甘草次酸多酰胺衍生物(11a~11n),收率78.6%~92.3%,其结构经1HNMR,13C NMR和IR表征.其中11i和11n的初步抑菌活性测试结果表明,杂环酰胺基团对甘草次酸衍生物的抗结核活性具有明显的增效作用.%Fourteen novel 18β-glyeyrrhetinic acid derivatives( 11a -11n) containing heterocyele amides were synthesized by multi-step amidation reactions from 18β-glycyiThetinic acid in yields of 78. 6% ~ 92. 3%. The structures were characterized by 1H NMR, 13C NMR and IR. The preliminary fungicidal activity tests of 11i and 11n showed that heterocyele amide groups might enhance the anti-tuberculosis activity of 18β-glvcyrrhetinic acid derivatives extraordinarily.

  4. 大位阻氨基酸Fmoc-Arg(Pbf)-OH与Rink Amide-AM树脂的高效缩合%Highly efficient condensation of sterically hindered amino acid fmoc-arg(Pbf)-OH and rink amide-AM resin

    Institute of Scientific and Technical Information of China (English)

    朱亮亮; 绳则翠; 周成; 祝社民; 陈英文; 沈树宝

    2012-01-01

    The coupling reactions of Fmoc-Arg( Pbf) -OH and Rink Amide-AM Resin with symmetrical anhydride method, active ester method and 2,6-dichlorobenoyl chloride (DCB) method, respectively, were investigated in a self-designed reactor which congregated the stirring,filtration,and bubbling function together. The effects of reaction strategy, solvent system, reaction time, molar ratio of reactants and stirring method on the yield of condensation reaction were performed. The results indicate that the DIC/HOBt/DMAP strategy is the best method. The optimal reaction conditions are shown as follows: 3 : 1 of molar ratio of the reactants, 3 h of reaction time and DMA/DCM ( 1 : 1, V/ V) as a solvent using nitrogen-assisted magnetic stir system. The highest yield of the condensation reaction is 93% .%采用集自动搅拌、过滤、鼓泡等多重功能于一体的自制多肽固相合成反应器,以对称酸酐法、活化酯法、2,6-二氯苯甲酰氯(DCB)法研究了大位阻氨基酸Fmoc-Arg (Pbf)-OH与Rink Amide-AM树脂的连接反应工艺.探讨了催化体系、溶剂体系、反应时间、反应物配比以及搅拌方式对合成Fmoc-Arg(Pbf)-Rink Amide-AM树脂反应的影响.结果表明,采用活化酯法(DIC/HOBt/DMAP)时连接率最高,最佳反应条件为:在采用N2辅助磁力拌系统,以体积比为1∶1的DMA/DCM为反应溶剂,氨基酸与树脂物质的量的比为3∶1,反应时间为3h时,连接率高达93%.

  5. Reliable determination of amidicity in acyclic amides and lactams.

    Science.gov (United States)

    Glover, Stephen A; Rosser, Adam A

    2012-07-06

    Two independent computational methods have been used for determination of amide resonance stabilization and amidicities relative to N,N-dimethylacetamide for a wide range of acyclic and cyclic amides. The first method utilizes carbonyl substitution nitrogen atom replacement (COSNAR). The second, new approach involves determination of the difference in amide resonance between N,N-dimethylacetamide and the target amide using an isodesmic trans-amidation process and is calibrated relative to 1-aza-2-adamantanone with zero amidicity and N,N-dimethylacetamide with 100% amidicity. Results indicate excellent coherence between the methods, which must be regarded as more reliable than a recently reported approach to amidicities based upon enthalpies of hydrogenation. Data for acyclic planar and twisted amides are predictable on the basis of the degrees of pyramidalization at nitrogen and twisting about the C-N bonds. Monocyclic lactams are predicted to have amidicities at least as high as N,N-dimethylacetamide, and the β-lactam system is planar with greater amide resonance than that of N,N-dimethylacetamide. Bicyclic penam/em and cepham/em scaffolds lose some amidicity in line with the degree of strain-induced pyramidalization at the bridgehead nitrogen and twist about the amide bond, but the most puckered penem system still retains substantial amidicity equivalent to 73% that of N,N-dimethylacetamide.

  6. Electrochemical reduction of nitrate in the presence of an amide

    Science.gov (United States)

    Dziewinski, Jacek J.; Marczak, Stanislaw

    2002-01-01

    The electrochemical reduction of nitrates in aqueous solutions thereof in the presence of amides to gaseous nitrogen (N.sub.2) is described. Generally, electrochemical reduction of NO.sub.3 proceeds stepwise, from NO.sub.3 to N.sub.2, and subsequently in several consecutive steps to ammonia (NH.sub.3) as a final product. Addition of at least one amide to the solution being electrolyzed suppresses ammonia generation, since suitable amides react with NO.sub.2 to generate N.sub.2. This permits nitrate reduction to gaseous nitrogen to proceed by electrolysis. Suitable amides include urea, sulfamic acid, formamide, and acetamide.

  7. Variation of protein backbone amide resonance by electrostatic field

    CERN Document Server

    Sharley, John N

    2015-01-01

    Amide resonance is found to be sensitive to electrostatic field with component parallel or antiparallel the amide C-N bond. This effect is linear and without threshold in the biologically plausible electrostatic field range -0.005 to 0.005 au. Variation of amide resonance varies Resonance Assisted Hydrogen Bonding such as occurs in the hydrogen bonded chains of backbone amides of protein secondary structures such as beta sheet and non-polyproline helix such as alpha helix, varying the stability of the secondary structure. The electrostatic properties including permittivity of amino acid residue sidegroups influence the electrostatic field component parallel or antiparallel the C-N bond of each amide. The significance of this factor relative to other factors in protein folding depends on the magnitude of electrostatic field component parallel or antiparallel the C-N bond of each amide, and preliminary protein-scale calculations of the magnitude of these components suggest this factor warrants investigation in ...

  8. Synthesis and preliminary mechanistic evaluation of 5-(p-tolyl)-1-(quinolin-2-yl)pyrazole-3-carboxylic acid amides with potent antiproliferative activity on human cancer cell lines.

    Science.gov (United States)

    Cankara Pirol, Şeyma; Çalışkan, Burcu; Durmaz, Irem; Atalay, Rengül; Banoglu, Erden

    2014-11-24

    We synthesized a series of novel amide derivatives of 5-(p-tolyl)-1-(quinolin-2-yl)pyrazole-3-carboxylic acid and assessed their antiproliferative activities against three human cancer cell lines (Huh7, human liver; MCF7, breast and HCT116, colon carcinoma cell lines) with the sulforhodamine B assay. Compound 4j with 2-chloro-4-pyridinyl group in the amide part exhibited promising cytotoxic activity against all cell lines with IC50 values of 1.6 μM, 3.3 μM and 1.1 μM for Huh7, MCF7 and HCT116 cells, respectively, and produced dramatic cell cycle arrest at SubG1/G1 phase as an indicator of apoptotic cell death induction. On the basis of their high potency in cellular environment, these straightforward pyrazole-3-carboxamide derivatives may possess potential in the design of more potent compounds for intervention with cancer cell proliferation.

  9. Incorporation of different crystallizable amide blocks in segmented poly(ester amide)s

    NARCIS (Netherlands)

    Lips, P.A.M.; Broos, R.; Heeringen, van M.J.M.; Dijkstra, P.J.; Feijen, J.

    2005-01-01

    High molecular weight segmented poly(ester amide)s were prepared by melt polycondensation of dimethyl adipate, 1,4-butanediol and a symmetrical bisamide-diol based on ε-caprolactone and 1,2-diaminoethane or 1,4-diaminobutane. FT-IR and WAXD analysis revealed that segmented poly(ester amide)s based

  10. Salt forms of the pharmaceutical amide dihydrocarbamazepine.

    Science.gov (United States)

    Buist, Amanda R; Kennedy, Alan R

    2016-02-01

    Carbamazepine (CBZ) is well known as a model active pharmaceutical ingredient used in the study of polymorphism and the generation and comparison of cocrystal forms. The pharmaceutical amide dihydrocarbamazepine (DCBZ) is a less well known material and is largely of interest here as a structural congener of CBZ. Reaction of DCBZ with strong acids results in protonation of the amide functionality at the O atom and gives the salt forms dihydrocarbamazepine hydrochloride {systematic name: [(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)(hydroxy)methylidene]azanium chloride, C15H15N2O(+)·Cl(-)}, dihydrocarbamazepine hydrochloride monohydrate {systematic name: [(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)(hydroxy)methylidene]azanium chloride monohydrate, C15H15N2O(+)·Cl(-)·H2O} and dihydrocarbamazepine hydrobromide monohydrate {systematic name: [(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)(hydroxy)methylidene]azanium bromide monohydrate, C15H15N2O(+)·Br(-)·H2O}. The anhydrous hydrochloride has a structure with two crystallographically independent ion pairs (Z' = 2), wherein both cations adopt syn conformations, whilst the two hydrated species are mutually isostructural and have cations with anti conformations. Compared to neutral dihydrocarbamazepine structures, protonation of the amide group is shown to cause changes to both the molecular (C=O bond lengthening and C-N bond shortening) and the supramolecular structures. The amide-to-amide and dimeric hydrogen-bonding motifs seen for neutral polymorphs and cocrystalline species are replaced here by one-dimensional polymeric constructs with no direct amide-to-amide bonds. The structures are also compared with, and shown to be closely related to, those of the salt forms of the structurally similar pharmaceutical carbamazepine.

  11. The ortho backbone amide linker (o-BAL) is an easily prepared and highly acid-labile handle for solid-phase synthesis

    DEFF Research Database (Denmark)

    Boas, Ulrik; Brask, Jesper; Christensen, J.B.;

    2002-01-01

    The tris(alkoxy)benzyl backbone amide linker (BAL) has found widespread application in solid-phase synthesis. The key intermediate for preparation of para BAL (p-BAL) is 2,6-dimethoxy-4-hydroxybenzaldehyde; several reports on its synthesis have appeared. However, the ortho analogue of the handle (o...

  12. Preparation of amidated derivatives of carboxymethylcellulose.

    Science.gov (United States)

    Taubner, Tomáš; Synytsya, Andriy; Čopíková, Jana

    2015-01-01

    Carboxymethylcellulose (CMC) was selected as substrate for amidation based on previous results described for monocarboxy cellulose (MCC) with the aim to prepare highly substituted products. In comparison with MCC containing uronic carboxyl groups at C-6 position, O-carboxymethyl groups in CMC should be more accessible for reagents because they are more distant from the polysaccharide chain. Two-step way of amidation was based on the esterification of CMC carboxyls by reaction with methanol and further amino-de-alkoxylation (aminolysis) of the obtained methyl ester with amidation reagents (n-alkylamines, hydrazine and hydroxylamine). Purity and substitution degree of the products were monitored by the vibration spectroscopic methods (FTIR and Raman) and organic elemental analysis. Analytical methods confirmed the preparation of highly or moderately substituted N-alkylamides, hydrazide and hydroxamic acid of CMC.

  13. Synthesis of Calix[4]resorcinarene Amide Derivatives

    Institute of Scientific and Technical Information of China (English)

    Chao Guo YAN; Yun GE

    2004-01-01

    Three different synthetic routes were developed to introduce carbamoyloxy functional groups at the upper periphery of two calix[4]resorcinarenes. By treating activated esters 2a-b with excess corresponding amine such as 3-(dimethylamino)propylamine 3, α-phenethylamine 4 and triethylenetetramine 5, six amide derivatives 6a~8b were obtained in high yield (Route 1). The pyridine-linked amide derivatives 9a-b were prepared by using acid chloride intermediate (Route 2). The amide derivatives 10a-b were obtained in moderate yields by direct alkylation of phenolic hydroxyl groups of 1a-b with N,N-dipropylchloroacetoamide in the presence of K2CO3/KI in acetone (Route 3).

  14. Microwave-assisted synthesis and characterization of camphoric acid chitosan amide%樟脑酸酰化壳聚糖的微波合成及性能表征

    Institute of Scientific and Technical Information of China (English)

    刘振明; 杨艳忠; 李静宇; 谢磊; 杨盛春

    2012-01-01

    以壳聚糖和樟脑酸为原料,在微波辐射下合成了一种新型壳聚糖衍生物——樟脑酸酰化壳聚糖,通过红外(FT-IR)、核磁(1H-NMR)、X-射线衍射(XRD)和热失重(TG)等测试手段对产物结构和性能进行了表征.结果表明樟脑酸通过酰胺键与壳聚糖结合,X-射线结果表明樟脑酸酰化壳聚糖的晶体结构发生了很大的改变,TG分析表明其热稳定性好于壳聚糖.%A new type chitosan derivative,camphoric acid chitosan amide, was synthesized by using of chitosan and camphoric acid as raw materials under microwave irradiation. The chemical structures and properties of the target product were investigated by fourier transform infrared (FT-IR), proton nuclear magnetic resonance spectra CH-NMR), thermogravimetric analyses (TG),and X-ray diffraction (XRD)measurements. The results showed that the camphoric acid is bonded with chitosan by amide-bond. The XRD pattern of product is signicantly different from the crystalline structure of chitosan. TG result demonstrated that thermal stability of the product is better than that of chitosan.

  15. Tertiary fatty amides as diesel fuel substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Serdari, Aikaterini; Lois, Euripides; Stournas, Stamoulis [National Technical Univ. of Athens, Dept. of Chemical Engineering, Athens (Greece)

    2000-07-01

    This paper presents experimental results regarding the impact of adding different tertiary amides of fatty acids to mineral diesel fuel; an assessment of the behaviour of these compounds as possible diesel fuel extenders is also included. Measurements of cetane number, cold flow properties (cloud point, pour point and CFPP), density, kinematic viscosity, flash point and distillation temperatures are reported, while initial experiments concerning the effects on particulate emissions are also described. Most of the examined tertiary fatty amides esters have very good performance and they can be easily prepared from fatty acids (biomass). Such compounds or their blends could be used as mineral diesel fuel or even fatty acid methylesters (FAME, biodiesel) substitutes or extenders. (Author)

  16. Transcription of the Human Microsomal Epoxide Hydrolase Gene (EPHX1) Is Regulated by PARP-1 and Histone H1.2. Association with Sodium-Dependent Bile Acid Transport.

    Science.gov (United States)

    Peng, Hui; Zhu, Qin-shi; Zhong, Shuping; Levy, Daniel

    2015-01-01

    Microsomal epoxide hydrolase (mEH) is a bifunctional protein that plays a central role in the metabolism of numerous xenobiotics as well as mediating the sodium-dependent transport of bile acids into hepatocytes. These compounds are involved in cholesterol homeostasis, lipid digestion, excretion of xenobiotics and the regulation of several nuclear receptors and signaling transduction pathways. Previous studies have demonstrated the critical role of GATA-4, a C/EBPα-NF/Y complex and an HNF-4α/CAR/RXR/PSF complex in the transcriptional regulation of the mEH gene (EPHX1). Studies also identified heterozygous mutations in human EPHX1 that resulted in a 95% decrease in mEH expression levels which was associated with a decrease in bile acid transport and severe hypercholanemia. In the present investigation we demonstrate that EPHX1 transcription is significantly inhibited by two heterozygous mutations observed in the Old Order Amish population that present numerous hypercholanemic subjects in the absence of liver damage suggesting a defect in bile acid transport into the hepatocyte. The identity of the regulatory proteins binding to these sites, established using biotinylated oligonucleotides in conjunction with mass spectrometry was shown to be poly(ADP-ribose)polymerase-1 (PARP-1) bound to the EPHX1 proximal promoter and a linker histone complex, H1.2/Aly, bound to a regulatory intron 1 site. These sites exhibited 71% homology and may represent potential nucleosome positioning domains. The high frequency of the H1.2 site polymorphism in the Amish population results in a potential genetic predisposition to hypercholanemia and in conjunction with our previous studies, further supports the critical role of mEH in mediating bile acid transport into hepatocytes.

  17. Synthesis of Novel Poly(aryl ether amide)s Containing the Phthalazinone Moiety

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-amin- ophenoxy)phenyl](2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one were successfully synthesized from readily available heterocyclic bisphenol-like monomers in two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety were successfully prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents.

  18. SYNTHESIS, CHARACTERIZATION OF CHIRAL POLY(ESTER AMIDE)S DERIVED FROM L-ISOLEUCINE

    Institute of Scientific and Technical Information of China (English)

    Xing-He Fan; Jing-Lun Zhou; Xiao-Fang Chen; Xin-Hua Wan; Qi-Feng Zhou

    2004-01-01

    A series of new optically active aromatic poly(ester amide)s containing a chiral group in the side chain prepared from the p-toluenesulfonic acid salt of o,o'-bis(leucyl)-hexanediol (TS-+LHD+TS-) and p-phthaloyl chloride and styrene-2,5-dicarbonyl chloride styrene have been synthesized by interfacial polymerization. The structure of the monomer is elucidated by FT-IR and elemental analysis. The thermal properties of the polymers were studied by DSC and TGA. The chiroptical properties of the above polymer have also been studied by circular dichroism (CD) spectroscopy. Results indicated that these polymers form helical structures.

  19. An Efficient Amide-Aldehyde-Alkene Condensation: Synthesis for the N-Allyl Amides.

    Science.gov (United States)

    Quan, Zheng-Jun; Wang, Xi-Cun

    2016-02-01

    The allylamine skeleton represents a significant class of biologically active nitrogen compounds that are found in various natural products and drugs with well-recognized pharmacological properties. In this personal account, we will briefly discuss the synthesis of allylamine skeletons. We will focus on showing a general protocol for Lewis acid-catalyzed N-allylation of electron-poor N-heterocyclic amides and sulfonamide via an amide-aldehyde-alkene condensation reaction. The substrate scope with respect to N-heterocyclic amides, aldehydes, and alkenes will be discussed. This method is also capable of preparing the Naftifine motif from N-methyl-1-naphthamide or methyl (naphthalene-1-ylmethyl)carbamate, with paraformaldehyde and styrene in a one-pot manner.

  20. Supramolecular chirality in organo-, hydro-, and metallogels derived from bis-amides of L-(+)-tartaric acid: formation of highly aligned 1D silica fibers and evidence of 5-c net SnS topology in a metallogel network.

    Science.gov (United States)

    Das, Uttam Kumar; Dastidar, Parthasarathi

    2012-10-01

    A series of bis-amides derived from L-(+)-tartaric acid was synthesized as potential low-molecular-weight gelators. Out of 14 bis-amides synthesized, 13 displayed organo-, hydro-, and ambidextrous gelation behavior. The gels were characterized by methods including circular dichroism, differential scanning calorimetry, optical and electron microscopy, and rheology. One of the gels derived from di-3-pyridyltartaramide (D-3-PyTA) displayed intriguing nanotubular morphology of the gel network, which was exploited as a template to generate highly aligned 1D silica fibers. The gelator D-3-PyTA was also exploited to generate metallogels by treatment with various Cu(II) /Zn(II) salts under suitable conditions. A structure-property correlation on the basis of single-crystal and powder X-ray diffraction data was attempted to gain insight into the structures of the gel networks in both organo- and metallogels. Such study led to the determination of the gel-network structure of the Cu(II) coordination-polymer-based metallogel, which displayed a 2D sheet architecture made of a chloride-bridged double helix that resembled a 5-c net SnS topology.

  1. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH) Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture.

    Science.gov (United States)

    Martins, Cyro José de Moraes; Genelhu, Virginia; Pimentel, Marcia Mattos Gonçalves; Celoria, Bruno Miguel Jorge; Mangia, Rogerio Fabris; Aveta, Teresa; Silvestri, Cristoforo; Di Marzo, Vincenzo; Francischetti, Emilio Antonio

    2015-01-01

    The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH), endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide) were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD) and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR), adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity.

  2. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture.

    Directory of Open Access Journals (Sweden)

    Cyro José de Moraes Martins

    Full Text Available The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH, endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR, adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity.

  3. Anticonvulsant effects of N-arachidonoyl-serotonin, a dual fatty acid amide hydrolase enzyme and transient receptor potential vanilloid type-1 (TRPV1) channel blocker, on experimental seizures: the roles of cannabinoid CB1 receptors and TRPV1 channels.

    Science.gov (United States)

    Vilela, Luciano R; Medeiros, Daniel C; de Oliveira, Antonio Carlos P; Moraes, Marcio F; Moreira, Fabricio A

    2014-10-01

    Selective blockade of anandamide hydrolysis, through the inhibition of the FAAH enzyme, has anticonvulsant effects, which are mediated by CB1 receptors. Anandamide, however, also activates TRPV1 channels, generally with an opposite outcome on neuronal modulation. Thus, we suggested that the dual FAAH and TRPV1 blockade with N-arachidonoyl-serotonin (AA-5-HT) would be efficacious in inhibiting pentylenetetrazole (PTZ)-induced seizures in mice. We also investigated the contribution of CB1 activation and TRPV1 blockade to the overt effect of AA-5-HT. In the first experiment, injection of AA-5-HT (0.3-3.0 mg/kg) delayed the onset and reduced the duration of PTZ (60 mg)-induced seizures in mice. These effects were reversed by pre-treatment with the CB1 antagonist, AM251 (1.0-3.0 mg/kg). Finally, we observed that administration of the selective TRPV1 antagonist, SB366791 (0.1-1 mg/kg), did not entirely mimic AA-5-HT effects. In conclusion, AA-5-HT alleviates seizures in mice, an effect inhibited by CB1 antagonism, but not completely mimicked by TRPV1 blockage, indicating that the overall effect of AA-5-HT seems to depend mainly on CB1 receptors. This may represent a new strategy for the development of drugs against seizures, epilepsies and related syndromes.

  4. Hydrogen Bonds between Acidic Protons from Alkynes (C–H···O and Amides (N–H···O and Carbonyl Oxygen Atoms as Acceptor Partners

    Directory of Open Access Journals (Sweden)

    Pierre Baillargeon

    2014-01-01

    Full Text Available Crystals of tert-butyl (2S-2-(prop-2-yn-1-ylcarbamoylpyrrolidine-1-carboxylate (Boc-L-Pro-NHCH2CCH have been obtained. The title compound crystallizes easily as sharp needles in orthorhombic system, space group P 21 21 21 with a = 9.2890(2, b = 9.7292(2, c = 15.7918(4 Å, V = 1427.18(6 Å3, and Z = 4. The main feature of the structure is the orientation of the carbamate and amide. Their dipoles add up and the molecule displays an electric dipole moment of 5.61 D from B3LYP/6-31G(d calculations. The antiparallel H bonding of amides and the alignment of dipoles induce columnar stacking (the dipole moment along the columnar a axis is 4.46 D for each molecule. The other components across the other axes are, therefore weaker, (3.17 D and 1.23 D along the b and c axes, resp.. The resulting anisotropic columns pack side by side, in an antiparallel fashion mostly by (alkyne CH···O=C (carbamate interactions.

  5. Peptidoglycan hydrolase fusions maintain their parental specificities.

    Science.gov (United States)

    Donovan, David M; Dong, Shengli; Garrett, Wes; Rousseau, Geneviève M; Moineau, Sylvain; Pritchard, David G

    2006-04-01

    The increased incidence of bacterial antibiotic resistance has led to a renewed search for novel antimicrobials. Avoiding the use of broad-range antimicrobials through the use of specific peptidoglycan hydrolases (endolysins) might reduce the incidence of antibiotic-resistant pathogens worldwide. Staphylococcus aureus and Streptococcus agalactiae are human pathogens and also cause mastitis in dairy cattle. The ultimate goal of this work is to create transgenic cattle that are resistant to mastitis through the expression of an antimicrobial protein(s) in their milk. Toward this end, two novel antimicrobials were produced. The (i) full-length and (ii) 182-amino-acid, C-terminally truncated S. agalactiae bacteriophage B30 endolysins were fused to the mature lysostaphin protein of Staphylococcus simulans. Both fusions display lytic specificity for streptococcal pathogens and S. aureus. The full lytic ability of the truncated B30 protein also suggests that the SH3b domain at the C terminus is dispensable. The fusions are active in a milk-like environment. They are also active against some lactic acid bacteria used to make cheese and yogurt, but their lytic activity is destroyed by pasteurization (63 degrees C for 30 min). Immunohistochemical studies indicated that the fusion proteins can be expressed in cultured mammalian cells with no obvious deleterious effects on the cells, making it a strong candidate for use in future transgenic mice and cattle. Since the fusion peptidoglycan hydrolase also kills multiple human pathogens, it also may prove useful as a highly selective, multipathogen-targeting antimicrobial agent that could potentially reduce the use of broad-range antibiotics in fighting clinical infections.

  6. Novel Synthesis of N-Substituted p-Hydroxybenzoic Amides on Soluble Polymer-Support

    Institute of Scientific and Technical Information of China (English)

    胡春玲; 陈祖兴; 杨桂春

    2003-01-01

    The synthesis of N-substituted p-hydroxybenzoic amides using a liquid phase approach is described. Poly(ethylene glycol)(PEG) and p-hydroxybenzoic acid were linked by oxalyl chloride to give compound 1, which was chlorinated by thionyl chloride, followed by amidation with NHR1R2 to yield compound 3. Hydrolysis of compound 3 gave the title amide 4.These crude library members were obtained in good yields with high purities.

  7. Mechanism of fluorescence quenching of tyrosine derivatives by amide group

    Science.gov (United States)

    Wiczk, Wiesław; Rzeska, Alicja; Łukomska, Joanna; Stachowiak, Krystyna; Karolczak, Jerzy; Malicka, Joanna; Łankiewicz, Leszek

    2001-06-01

    The difference between fluorescence lifetimes of the following amino acids: phenylalanine (Phe), tyrosine (Tyr), ( O-methyl)tyrosine (Tyr(Me)), (3-hydroxy)tyrosine (Dopa), (3,4-dimethoxy)phenylalanine (Dopa(Me) 2) and their amides was used to testify the mechanism of fluorescence quenching of aromatic amino acids by the amide group. On the basis of the Marcus theory of photoinduced electron transfer parabolic relationships between ln kET and ionization potentials reduced by energy of excitation ( IP-E ∗0,0) for the above-mentioned amino acids were obtained. This finding indicates the occurrence of photoinduced electron transfer from the excited chromophore group to the amide group.

  8. Les lipases sont des hydrolases atypiques : principales caractéristiques et applications

    Directory of Open Access Journals (Sweden)

    Fickers P.

    2008-01-01

    Full Text Available ipases are atypical hydrolases: principal characteristics and applications. Due to their kinetic and substrate specificities, triacylglycerol acyl-hydrolases or lipases are atypical enzymes. In function of their microenvironment, lipases are able to act as hydrolases in aqueous solution or as biocatalysts in organic synthesis. As hydrolases, they are responsible of the triglycerids catabolism into fatty acids and glycerol. In many organisms, this reaction plays a major role in the fat and lipid metabolism. In addition, lipases are also able to hydrolyse phospholipids and cholesterol esters. In organic solvent, lipases could catalyse reactions such as esterifications, acidolysis or alcoolysis with enantio-, regio- and chimioselectivity. Lipases form a mixed class of enzyme due to their animal, vegetal or microbial origins. All those properties led to the development of many applications in the food and chemical industries but also in the medical and therapeutic field.

  9. Possible evidence of amide bond formation between sinapinic acid and lysine-containing bacterial proteins by matrix-assisted laser desorption/ionization (MALDI) at 355 nm

    Science.gov (United States)

    We previously reported the apparent formation of matrix adducts of 3,5-dimethoxy-4-hydroxy-cinnamic acid (sinapinic acid or SA) via covalent attachment to disulfide bond-containing proteins (HdeA, HdeB and YbgS) from bacterial cell lysates ionized by matrix-assisted laser desorption/ionization (MALD...

  10. Alpha-amidated peptides derived from pro-opiomelanocortin in normal human pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Johnsen, A H

    1988-01-01

    Normal human pituitaries were extracted in boiling water and acetic acid, and the alpha-amidated peptide products of pro-opiomelanocortin (POMC), alpha-melanocyte-stimulating hormone (alpha MSH), gamma-melanocyte-stimulating hormone (gamma 1MSH), and amidated hinge peptide (HP-N), as well...

  11. A nordehydroabietyl amide-containing chiral diene for rhodium-catalysed asymmetric arylation to nitroolefins.

    Science.gov (United States)

    Li, Ruikun; Wen, Zhongqing; Wu, Na

    2016-11-29

    A highly enantioselective rhodium catalysed asymmetric arylation (RCAA) of nitroolefins with arylboronic acids is presented using a newly developed, C1-symmetric, non-covalent interacted, phellandrene derived, nordehydroabietyl amide-containing chiral diene under mild conditions. Stereoelectronic effects were studied, suggesting an activation of the bound substrate through the secondary amide as a hydrogen-bond donor.

  12. Purification and Characterization of Conjugated Bile Salt Hydrolase from Bifidobacterium longum BB536

    OpenAIRE

    Grill, J; Schneider, F.; Crociani, J.; Ballongue, J.

    1995-01-01

    Bifidobacterium species deconjugate taurocholic, taurodeoxycholic, taurochenodeoxycholic, glycocholic, glycodeoxycholic, and glycochenodeoxycholic acids. The enzyme level increases in the growth phase. No increase in activity is observed for the cytoplasmic enzyme after addition of conjugated bile acids to a stationary-phase culture. Conjugated bile salt hydrolase (BSH) was purified from Bifidobacterium longum BB536. Its apparent molecular mass in denaturing polyacrylamide gel electrophoresis...

  13. Synthesis of novel poly(aryl ether amide)s containing the phthalazinone moiety

    Institute of Scientific and Technical Information of China (English)

    CHENG, Lin(程琳); JIAN, Xi- Gao(蹇锡高)

    2000-01-01

    Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4- [ 4-( 4-aminophenoxy ) phenyl ]-( 2H )-phtha-lazin-1-one and 1, 2-dihydro-2-( 4-aminophenyl)-4-[ 4-( 4-aminophenoxy)-3, 5-dimethylphenyl]-(2H)-phthalazin-1-one were successfully synthesized using readily available heterocyclic bisphenol-like monomers through two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety with inherent viscosities of 1.16-1.67 dL/g were prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. The polymers were readily soluble in a variety of solvents such as N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc),dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidinone (NMP), and pyridine. The polymers had high glass transition tenperatured(Tg) in the 291-329℃ range.

  14. Crystallochemical study of amides derived from 6{alpha}, 7{beta}-diidroxivoacapan-17{beta}-oic acid by X-ray diffraction; Estudo cristaloquimico de amidas derivadas do acido 6{alpha}, 7{beta}-di- hidroxivouacapan-17 {beta}-oico por difracao de raios-X

    Energy Technology Data Exchange (ETDEWEB)

    Branco, Marcello Cardoso; Prado Gambardella, Maria Teresa do [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Quimica. Dept. de Quimica e Fisica Molecular

    1995-12-31

    Abstract. The 6{alpha}, 7{beta}-diidroxivoacapan-17{beta}-oic acid (DVA) is a Furane-diterpene isolated from Peterodon genus. It has anti inflammatory and analgesic properties. The purpose of this work is the characterization of amides derived from DVA, in order to understand the relationship between Chemical Structure and Biological Activity of Vouacapanes. The structures of DVA derivatives will be solved by single-crystal X-ray diffraction. (author) 15 refs., 2 figs.

  15. Effects of calcium salts of long-chain fatty acids and rumen-protected methionine on plasma concentrations of ghrelin, glucagon-like peptide-1 (7 to 36) amide and pancreatic hormones in lactating cows.

    Science.gov (United States)

    Fukumori, R; Sugino, T; Shingu, H; Moriya, N; Hasegawa, Y; Kojima, M; Kangawa, K; Obitsu, T; Kushibiki, S; Taniguchi, K

    2012-02-01

    Our objective was to determine the effects of calcium salts of long-chain fatty acids (CLFAs) and rumen-protected methionine (RPM) on plasma concentrations of ghrelin, glucagon-like peptide-1 (7 to 36) amide, and pancreatic hormones in lactating cows. Four Holstein cows in midlactation were used in a 4 by 4 Latin square experiment in each 2-wk period. Cows were fed corn silage-based diets with supplements of CLFAs (1.5% added on dry matter basis), RPM (20 g/d), CLFAs plus RPM, and without supplement. Jugular blood samples were taken from 1 h before to 2 h after morning feeding at 10-min intervals on day 12 of each period. CLFAs decreased dry matter intake, but RPM did not affect dry matter intake. Both supplements of CLFAs and RPM did not affect metabolizable energy intake and milk yield and composition. Plasma concentrations of NEFAs, triglyceride (TG), and total cholesterol (T-Cho) were increased with CLFAs alone, but increases of plasma concentrations of TG and T-Cho were moderated by CLFAs plus RPM. Calcium salts of long-chain fatty acids increased plasma ghrelin concentration, and the ghrelin concentration with CLFAs plus RPM was the highest among the treatments. Plasma concentrations of glucagon-like peptide-1, glucagon, and insulin were decreased with CLFAs, whereas adding RPM moderated the decrease of plasma glucagon concentration by CLFAs. These results indicate that the addition of methionine to cows given CLFAs increases plasma concentrations of ghrelin and glucagon associated with the decrease in plasma concentrations of TG and T-Cho.

  16. Preparation of a new chiral stationary phase for HPLC based on the (R)- 1-phenyl-2-(4-methylphenyl)ethylamine amide derivative of (S)-valine and 2-chloro-3,5-dinitrobenzoic acid: enantioseparation of amino acid derivatives and pyrethroid insecticides.

    Science.gov (United States)

    Tan, Xulin; Hou, Shicong; Jiang, Jingli; Wang, Min

    2007-08-01

    A novel chiral stationary phase (CSP) for HPLC was prepared by bonding (R)-1-phenyl-2-(4-methylphenyl)ethylamine amide derivative of (S)-valine to aminopropyl silica gel through a 2-amino-3,5-dinitro-1-carboxamido-benzene unit. The CSP was used for the separation of some amino acid derivatives and pyrethroid insecticides by chiral HPLC. Satisfactory baseline separation required optimization of the variables of mobile phase composition. Use of dichloromethane as modifier in the mobile phase gave baseline separations of amino acid derivatives. The two enantiomers of fenpropathrin and four stereoisomers of fenvalerate were baseline separated using hexane-dichloromethane-ethanol as mobile phase. The results show that the enantioselectivity of the new CSP is better than Pirkle type 1-A column for these compounds. Only partial separations were observed for the stereoisomers of cypermethrin and cyfluthrin, which gave even and eight peaks, respectively.

  17. Endocannabinoid and cannabinoid-like fatty acid amide levels correlate with pain-related symptoms in patients with IBS-D and IBS-C: a pilot study.

    Directory of Open Access Journals (Sweden)

    Jakub Fichna

    Full Text Available AIMS: Irritable bowel syndrome (IBS is a functional gastrointestinal (GI disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients. METHODS: AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D and constipation-predominant (IBS-C patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls. RESULTS: Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C. CONCLUSION: IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms.

  18. Decreased body weight and hepatic steatosis with altered fatty acid ethanolamide metabolism in aged L-Fabp -/- mice.

    Science.gov (United States)

    Newberry, Elizabeth P; Kennedy, Susan M; Xie, Yan; Luo, Jianyang; Crooke, Rosanne M; Graham, Mark J; Fu, Jin; Piomelli, Daniele; Davidson, Nicholas O

    2012-04-01

    The tissue-specific sources and regulated production of physiological signals that modulate food intake are incompletely understood. Previous work showed that L-Fabp(-/-) mice are protected against obesity and hepatic steatosis induced by a high-fat diet, findings at odds with an apparent obesity phenotype in a distinct line of aged L-Fabp(-/-) mice. Here we show that the lean phenotype in L-Fabp(-/-) mice is recapitulated in aged, chow-fed mice and correlates with alterations in hepatic, but not intestinal, fatty acid amide metabolism. L-Fabp(-/-) mice exhibited short-term changes in feeding behavior with decreased food intake, which was associated with reduced abundance of key signaling fatty acid ethanolamides, including oleoylethanolamide (OEA, an agonist of PPARα) and anandamide (AEA, an agonist of cannabinoid receptors), in the liver. These reductions were associated with increased expression and activity of hepatic fatty acid amide hydrolase-1, the enzyme that degrades both OEA and AEA. Moreover, L-Fabp(-/-) mice demonstrated attenuated responses to OEA administration, which was completely reversed with an enhanced response after administration of a nonhydrolyzable OEA analog. These findings demonstrate a role for L-Fabp in attenuating obesity and hepatic steatosis, and they suggest that hepatic fatty acid amide metabolism is altered in L-Fabp(-/-) mice.

  19. 全细胞高通量筛选α-氨基酸酯水解酶突变体的方法%Cell-based high throughput screening of α-amino acid ester hydrolase variants

    Institute of Scientific and Technical Information of China (English)

    叶丽娟; 王佳珉; 王辂; 曹毅

    2012-01-01

    [Objective] The study aimed to develop an efficient and sensitive high-throughput method to obtain alpha-amino acid ester hydrolase (AEH) with improved activity or thermo-stability. [Methods] Standard curve was made based on the fact that hydrolysis of cefaclor in alkaline buffer yields a derivate which has specific absorbance at 340 nm. Whole cell-based ultra-violet spectrophotometric method was applied to screen the cefaclor synthesis activity of AEH variants at a high-throughput scale. [Results] Beer's Law is obeyed in the range of (0.1-0.6)xl0~3 mol/L cefaclor. The average recovery is 99.8%-101.3%. 2 300 Clones obtained by one round of site-directed saturated mutagenesis were screened by this method. Three variants with more than 1.4-fold kcat and 4 variants with T50 5 ℃ more than wild type were obtained. [Conclusion] The screening method was precise and reliable. The screen capacity can be up to 2 000 samples per day, which was in the scale of high-throughput screening.%[目的]建立高效敏感的高通量筛选方法,用于筛选头孢克洛合成活性提高或热稳定性提高的α-氨基酸酯水解酶.[方法]根据头孢克洛在碱性条件下水解生成的衍生物在340 nm处有特征吸收峰的原理,制作出标准曲线.采用全细胞96孔板紫外分光光度法高通量测定α-氨基酸酯水解酶突变体的头孢克洛合成活性.[结果]头孢克洛含量与△A340-405在(0.1-0.6)×10-3 mol/L浓度范围内有良好的线性关系,服从朗伯-比尔定律,平均回收率为99.8%-101.3%.一轮定点饱和突变产生的2 300个克隆经该方法的筛选,获得3株Kcat提高40%以上,4株半失活温度较野生型提高5℃以上的突变体酶.[结论]该方法准确可靠,每天筛选量可达到2 000个反应,达到高通量筛选的要求.

  20. Backbone amide linker strategy

    DEFF Research Database (Denmark)

    Shelton, Anne Pernille Tofteng; Jensen, Knud Jørgen

    2013-01-01

    amino acid residue by reductive amination. This can be used as a general approach for the introduction of other C-terminal modifications as well as functionalities, such as fluorophors. The second step is an acylation of a secondary amine, followed by standard Fmoc-based solid-phase synthesis...

  1. CuS-poly (N-isopropylacryl-amide-co-acrylic acid) composite microspheres with patterned surface structures:preparation and characterization

    Institute of Scientific and Technical Information of China (English)

    YANG Juxiang; FANG Yu; BAI Chaoliang; HU Daodao; ZHANG Ying

    2004-01-01

    N-isopropylacrylamide (NIPAM) and acrylic acid (AA) copolymer microspheres with various compositions were prepared by reverse suspension polymerization technique. The microspheres thus prepared were employed as micro-reactors for the deposition of CuS. In this way, several CuS-P(NIPAM-co-AA) composite microspheres with different surface morphologies were prepared. It was demonstrated that the surface structures of the composite microspheres can be tailored to a certain extent by varying the ratio of the two monomer units in the template (microgels) and/or the amount of CuS deposited. It is in prospect that the inherent advantages of microgel templates (the size, composition, charge nature and density, and crosslinking density could be easily controlled) would make the microgel template method extremely useful in the preparation of composite microspheres with different patterned surface structures.

  2. 40 CFR 721.3720 - Fatty amide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty amide. 721.3720 Section 721.3720... Fatty amide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a fatty amide (PMN P-91-87) is subject to reporting under this...

  3. 40 CFR 721.2120 - Cyclic amide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Cyclic amide. 721.2120 Section 721... Cyclic amide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as a cyclic amide (PMN P-92-131) is subject to reporting under this section for...

  4. How to find soluble proteins: a comprehensive analysis of alpha/beta hydrolases for recombinant expression in E. coli

    Directory of Open Access Journals (Sweden)

    Barth Sandra

    2005-04-01

    Full Text Available Abstract Background In screening of libraries derived by expression cloning, expression of active proteins in E. coli can be limited by formation of inclusion bodies. In these cases it would be desirable to enrich gene libraries for coding sequences with soluble gene products in E. coli and thus to improve the efficiency of screening. Previously Wilkinson and Harrison showed that solubility can be predicted from amino acid composition (Biotechnology 1991, 9(5:443–448. We have applied this analysis to members of the alpha/beta hydrolase fold family to predict their solubility in E. coli. alpha/beta hydrolases are a highly diverse family with more than 1800 proteins which have been grouped into homologous families and superfamilies. Results The predicted solubility in E. coli depends on hydrolase size, phylogenetic origin of the host organism, the homologous family and the superfamily, to which the hydrolase belongs. In general small hydrolases are predicted to be more soluble than large hydrolases, and eukaryotic hydrolases are predicted to be less soluble in E. coli than prokaryotic ones. However, combining phylogenetic origin and size leads to more complex conclusions. Hydrolases from prokaryotic, fungal and metazoan origin are predicted to be most soluble if they are of small, medium and large size, respectively. We observed large variations of predicted solubility between hydrolases from different homologous families and from different taxa. Conclusion A comprehensive analysis of all alpha/beta hydrolase sequences allows more efficient screenings for new soluble alpha/beta hydrolases by the use of libraries which contain more soluble gene products. Screening of hydrolases from families whose members are hard to express as soluble proteins in E. coli should first be done in coding sequences of organisms from phylogenetic groups with the highest average of predicted solubility for proteins of this family. The tools developed here can be used

  5. A new insight into the physiological role of bile salt hydrolase among intestinal bacteria from the genus Bifidobacterium.

    Directory of Open Access Journals (Sweden)

    Piotr Jarocki

    Full Text Available This study analyzes the occurrence of bile salt hydrolase in fourteen strains belonging to the genus Bifidobacterium. Deconjugation activity was detected using a plate test, two-step enzymatic reaction and activity staining on a native polyacrylamide gel. Subsequently, bile salt hydrolases from B. pseudocatenulatum and B. longum subsp. suis were purified using a two-step chromatographic procedure. Biochemical characterization of the bile salt hydrolases showed that the purified enzymes hydrolyzed all of the six major human bile salts under the pH and temperature conditions commonly found in the human gastrointestinal tract. Next, the dynamic rheometry was applied to monitor the gelation process of deoxycholic acid under different conditions. The results showed that bile acids displayed aqueous media gelating properties. Finally, gel-forming abilities of bifidobacteria exhibiting bile salt hydrolase activity were analyzed. Our investigations have demonstrated that the release of deconjugated bile acids led to the gelation phenomenon of the enzymatic reaction solution containing purified BSH. The presented results suggest that bile salt hydrolase activity commonly found among intestinal microbiota increases hydrogel-forming abilities of certain bile salts. To our knowledge, this is the first report showing that bile salt hydrolase activity among Bifidobacterium is directly connected with the gelation process of bile salts. In our opinion, if such a phenomenon occurs in physiological conditions of human gut, it may improve bacterial ability to colonize the gastrointestinal tract and their survival in this specific ecological niche.

  6. Structure-activity studies on the C-terminal amide of substance P.

    Science.gov (United States)

    Escher, E; Couture, R; Poulos, C; Pinas, N; Mizrahi, J; Theodoropoulos, D; Regoli, D

    1982-11-01

    Twelve C-terminal heptapeptide analogues of substance P have been synthesized by solid phase and by the classical solution method. The modifications concerned all the C-terminal primary amide of SP and should therefore help to understand the biological significance of this carboxamide, as evaluated by in vivo and in vitro bioassays. From the results it can be seen that not the slightest change of the two amide protons is tolerated without an important loss of activity: replacement of one or two amide protons with alkyl groups, extension of the amide to the hydrazide and its alkyl analogues, and exchange of the amide with an ester or a carboxylic acid all reduce the relative activity/affinity at least by 2-fold. It is not clear for what reason all these modifications produce such a drastic activity reduction.

  7. Synthesis of amide-functionalized cellulose esters by olefin cross-metathesis.

    Science.gov (United States)

    Meng, Xiangtao; Edgar, Kevin J

    2015-11-05

    Cellulose esters with amide functionalities were synthesized by cross-metathesis (CM) reaction of terminally olefinic esters with different acrylamides, catalyzed by Hoveyda-Grubbs 2nd generation catalyst. Chelation by amides of the catalyst ruthenium center caused low conversions using conventional solvents. The effects of both solvent and structure of acrylamide on reaction conversion were investigated. While the inherent tendency of acrylamides to chelate Ru is governed by the acrylamide N-substituents, employing acetic acid as a solvent significantly improved the conversion of certain acrylamides, from 50% to up to 99%. Homogeneous hydrogenation using p-toluenesulfonyl hydrazide successfully eliminated the α,β-unsaturation of the CM products to give stable amide-functionalized cellulose esters. The amide-functionalized product showed higher Tg than its starting terminally olefinic counterpart, which may have resulted from strong hydrogen bonding interactions of the amide functional groups.

  8. Cellular Inhibition of Checkpoint Kinase 2 (Chk2) and Potentiation of Camptothecins and Radiation by the Novel Chk2 Inhibitor PV1019 [7-Nitro-1H-indole-2-carboxylic acid {4-[1-(guanidinohydrazone)-ethyl]-phenyl}-amide

    Energy Technology Data Exchange (ETDEWEB)

    Jobson, Andrew G.; Lountos, George T.; Lorenzi, Philip L.; Llamas, Jenny; Connelly, John; Cerna, David; Tropea, Joseph E.; Onda, Akikazu; Zoppoli, Gabriele; Kondapaka, Sudhir; Zhang, Guangtao; Caplen, Natasha J.; Cardellina, II, John H.; Yoo, Stephen S.; Monks, Anne; Self, Christopher; Waugh, David S.; Shoemaker, Robert H.; Pommier, Yves; (NIH)

    2010-04-05

    Chk2 is a checkpoint kinase involved in the ataxia telangiectasia mutated pathway, which is activated by genomic instability and DNA damage, leading to either cell death (apoptosis) or cell cycle arrest. Chk2 provides an unexplored therapeutic target against cancer cells. We recently reported 4,4'-diacetyldiphenylurea-bis(guanylhydrazone) (NSC 109555) as a novel chemotype Chk2 inhibitor. We have now synthesized a derivative of NSC 109555, PV1019 (NSC 744039) [7-nitro-1H-indole-2-carboxylic acid {l_brace}4-[1-(guanidinohydrazone)-ethyl]-phenyl{r_brace}-amide], which is a selective submicromolar inhibitor of Chk2 in vitro. The cocrystal structure of PV1019 bound in the ATP binding pocket of Chk2 confirmed enzymatic/biochemical observations that PV1019 acts as a competitive inhibitor of Chk2 with respect to ATP. PV1019 was found to inhibit Chk2 in cells. It inhibits Chk2 autophosphorylation (which represents the cellular kinase activation of Chk2), Cdc25C phosphorylation, and HDMX degradation in response to DNA damage. PV1019 also protects normal mouse thymocytes against ionizing radiation-induced apoptosis, and it shows synergistic antiproliferative activity with topotecan, camptothecin, and radiation in human tumor cell lines. We also show that PV1019 and Chk2 small interfering RNAs can exert antiproliferative activity themselves in the cancer cells with high Chk2 expression in the NCI-60 screen. These data indicate that PV1019 is a potent and selective inhibitor of Chk2 with chemotherapeutic and radiosensitization potential.

  9. Robust trans-amide helical structure of oligomers of bicyclic mimics of β-proline: impact of positional switching of bridgehead substituent on amide cis-trans equilibrium.

    Science.gov (United States)

    Wang, Siyuan; Otani, Yuko; Liu, Xin; Kawahata, Masatoshi; Yamaguchi, Kentaro; Ohwada, Tomohiko

    2014-06-06

    Because homooligomers of 7-azabicyclo[2.2.1]heptane-2-endo-carboxylic acid, a bridged β-proline analogue with a substituent installed at the remote C4-bridgehead position, completely biased the amide cis-trans equilibrium to the cis-amide structure, we expected that introduction of a substituent at the C1-bridgehead position adjacent to the carboxylic acid moiety, rather than the remote C4-bridgehead position, would tip the cis-trans amide equilibrium toward trans-amide structure without the aid of hydrogen bonding. Thus, in this work we established an efficient synthetic route to an optically active bicyclic analogue of 1,1-disubstituted β-proline, bearing a substituent at the C1-bridgehead position. Crystallographic, spectroscopic, and computational studies showed that indeed oligomers of this analogue take a consistent helical structure involving all-trans-amide linkages, independently of the number of residues, from the dimer up to the octamer. Oligomers composed of (R)-β-amino acid units form an extended left-handed helix with about 2.7 residues per turn and an approximately 4.0 Å rise per residue, characterized by complete lack of main-chain hydrogen bonding. This unique helical structure shows some similarity in shape to the trans-amide-based polyproline II (PPII) helix. The present helix was stable in various kinds of solvents such as alcohols. The present work provided a fundamental structural basis for future applications.

  10. Chiral separation of amides using supercritical fluid chromatography.

    Science.gov (United States)

    Xiang, Yanqiao; Dunetz, Joshua R; Lovdahl, Michael

    2013-06-07

    Nine amide derivatives bearing α-stereocenters as well as different substitutions on the amide nitrogen were synthesized via an n-propanephosphonic acid cyclic anhydride (T3P)-mediated coupling, and their enantiomeric pairs were separated using supercritical fluid chromatography (SFC). Five polysaccharide-based chiral stationary phases (CSPs), Chiralcel OD-H, and OJ-H, and Chiralpak AD-H, AS-H and IC columns were explored for the chiral separation of these compounds. None of the compounds could be resolved on all five columns, and no single column could separate all nine pairs of enantiomers. Comparatively, the IC and OD-H columns showed the best results for this group of amides, yielding baseline separations for eight of nine pairs. The type of polar functional group and aromatic substitution in the CSPs and the substitutions on the amide nitrogen had a significant impact on the enantiomeric resolution of the compounds in the interaction between the analyte and the stationary phases. The potential separation mechanism and the effect of substitutions in the CSPs and amide solutes on the separation are discussed. The effects of the organic modifiers, modifier composition, mobile phase additives, and temperature were investigated for the separation of these amides on the IC or the OD-H column. Baseline resolution was achieved under optimized chromatographic conditions using an IC or an OD-H column. Linearity, reproducibility, and limit of quantitation were also demonstrated for the compound 9. Approximately three-fold improvement in signal-to-noise was observed using a SFC system with better instrument design.

  11. Genetically reduced soluble epoxide hydrolase activity and risk of stroke and other cardiovascular disease

    DEFF Research Database (Denmark)

    Lee, Julie; Dahl, Morten; Grande, Peer;

    2010-01-01

    BACKGROUND AND PURPOSE: The development of stroke has been linked to lowered levels of epoxyeicosatrienoic acids in the cerebral microvasculature. These substances are metabolized by the enzyme-soluble epoxide hydrolase encoded by the EPHX2 gene. We tested whether genetically reduced soluble...

  12. Structure-guided engineering of molinate hydrolase for the degradation of thiocarbamate pesticides.

    Science.gov (United States)

    Leite, José P; Duarte, Márcia; Paiva, Ana M; Ferreira-da-Silva, Frederico; Matias, Pedro M; Nunes, Olga C; Gales, Luís

    2015-01-01

    Molinate is a recalcitrant thiocarbamate used to control grass weeds in rice fields. The recently described molinate hydrolase, from Gulosibacter molinativorax ON4T, plays a key role in the only known molinate degradation pathway ending in the formation of innocuous compounds. Here we report the crystal structure of recombinant molinate hydrolase at 2.27 Å. The structure reveals a homotetramer with a single mononuclear metal-dependent active site per monomer. The active site architecture shows similarities with other amidohydrolases and enables us to propose a general acid-base catalysis mechanism for molinate hydrolysis. Molinate hydrolase is unable to degrade bulkier thiocarbamate pesticides such as thiobencarb which is used mostly in rice crops. Using a structural-based approach, we were able to generate a mutant (Arg187Ala) that efficiently degrades thiobencarb. The engineered enzyme is suitable for the development of a broader thiocarbamate bioremediation system.

  13. Structure-guided engineering of molinate hydrolase for the degradation of thiocarbamate pesticides.

    Directory of Open Access Journals (Sweden)

    José P Leite

    Full Text Available Molinate is a recalcitrant thiocarbamate used to control grass weeds in rice fields. The recently described molinate hydrolase, from Gulosibacter molinativorax ON4T, plays a key role in the only known molinate degradation pathway ending in the formation of innocuous compounds. Here we report the crystal structure of recombinant molinate hydrolase at 2.27 Å. The structure reveals a homotetramer with a single mononuclear metal-dependent active site per monomer. The active site architecture shows similarities with other amidohydrolases and enables us to propose a general acid-base catalysis mechanism for molinate hydrolysis. Molinate hydrolase is unable to degrade bulkier thiocarbamate pesticides such as thiobencarb which is used mostly in rice crops. Using a structural-based approach, we were able to generate a mutant (Arg187Ala that efficiently degrades thiobencarb. The engineered enzyme is suitable for the development of a broader thiocarbamate bioremediation system.

  14. Determination of the equilibrium micelle-inserting position of the fusion peptide of gp41 of human immunodeficiency virus type 1 at amino acid resolution by exchange broadening of amide proton resonances

    Energy Technology Data Exchange (ETDEWEB)

    Chang, D.-K.; Cheng, S.-F. [Academia Sinica, Institute of Chemistry (China)

    1998-11-15

    The exchange broadening of backbone amide proton resonances of a 23-mer fusion peptide of the transmembrane subunit of HIV-1 envelope glycoprotein gp41, gp41-FP, was investigated at pH 5 and 7 at room temperature in perdeuterated sodium dodecyl sulfate (SDS) micellar solution. Comparison of resonance peaks for these pHs revealed an insignificant change in exchange rate between pH 5 and 7 for amide protons of residues 4 through 14, while the exchange rate increase at neutral pH was more prominent for amide protons of the remaining residues, with peaks from some protons becoming undetectable. The relative insensitivity to pH of the exchange for the amide protons of residues 4 through 14 is attributable to the drastic reduction in [OH-] in the micellar interior, leading to a decreased exchange rate. The A15-G16 segment represents a transition between these two regimes. The data are thus consistent with the notion that the peptide inserts into the hydrophobic core of a membrane-like structure and the A15-G16 dipeptide is located at the micellar-aqueous boundary.

  15. T. thermophila group I introns that cleave amide bonds

    Science.gov (United States)

    Joyce, Gerald F. (Inventor)

    1997-01-01

    The present invention relates to nucleic acid enzymes or enzymatic RNA molecules that are capable of cleaving a variety of bonds, including phosphodiester bonds and amide bonds, in a variety of substrates. Thus, the disclosed enzymatic RNA molecules are capable of functioning as nucleases and/or peptidases. The present invention also relates to compositions containing the disclosed enzymatic RNA molecule and to methods of making, selecting, and using such enzymes and compositions.

  16. Preparation and phytotoxicity of novel kaurane diterpene amides with potential use as herbicides.

    Science.gov (United States)

    Boaventura, Maria Amélia Diamantino; Pereira, Rondinelle Gomes; de Oliveira Freitas, Luiza B; Dos Reis, Leandro Alves; da Silva Vieira, Henriete

    2008-05-14

    Novel kaurane ditepene monoamides were synthesized in good yields directly from kaurenoic ( 1) and grandiflorenic ( 2) acids and unprotected symmetrical diamines, using a modified protocol for monoacylation. Amides from 1 and 2 and monoamines were also obtained and tested against seed germination and growth of radicle and shoot of Lactuca sativa (lettuce), at 10 (-3), 10 (-5), and 10 (-7) M. Amides from symmetrical diamines showed significant inhibitory activity at higher concentrations.

  17. Zirconyl chloride promoted highly efficient solid phase synthesis of amide derivatives

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    An efficient solid phase route for the synthesis of amide derivatives by the reaction of carboxylic acids with urea in the presence of catalytic amount of zirconyl chloride under microwave irradiation conditions was described. In this way, a range of interesting amide derivatives was obtained in good to excellent yields. The catalyst was recycled with fresh reactants and it gave almost similar results without significant loss of activity up to the third run.

  18. Epoxides and soluble epoxide hydrolase in cardiovascular physiology.

    Science.gov (United States)

    Imig, John D

    2012-01-01

    Epoxyeicosatrienoic acids (EETs) are arachidonic acid metabolites that importantly contribute to vascular and cardiac physiology. The contribution of EETs to vascular and cardiac function is further influenced by soluble epoxide hydrolase (sEH) that degrades EETs to diols. Vascular actions of EETs include dilation and angiogenesis. EETs also decrease inflammation and platelet aggregation and in general act to maintain vascular homeostasis. Myocyte contraction and increased coronary blood flow are the two primary EET actions in the heart. EET cell signaling mechanisms are tissue and organ specific and provide significant evidence for the existence of EET receptors. Additionally, pharmacological and genetic manipulations of EETs and sEH have demonstrated a contribution for this metabolic pathway to cardiovascular diseases. Given the impact of EETs to cardiovascular physiology, there is emerging evidence that development of EET-based therapeutics will be beneficial for cardiovascular diseases.

  19. Poly(amide-graft-acrylate) interfacial compounds

    Science.gov (United States)

    Zamora, Michael Perez

    Graft copolymers with segments of dissimilar chemistries have been shown to be useful in a variety of applications as surfactants, compatibilizers, impact modifiers, and surface modifiers. The most common route to well defined graft copolymers is through the use of macromonomers, polymers containing a reactive functionality and thus capable of further polymerization. However, the majority of the studies thus far have focused on the synthesis of macromonomers capable of reacting with vinyl monomers to form graft copolymers. This study focused on the synthesis of macromonomers capable of participating in condensation polymerizations. A chain transfer functionalization method was utilized. Cysteine was evaluated as a chain transfer agent for the synthesis of amino acid functionalized poly(acrylate) and poly(methacrylate) macromonomers. Low molar mass, functionalized macromonomers were produced. These macromonomers were proven to be capable of reacting with amide precursors to form poly(amide-g-acrylate) graft copolymers. Macromonomers and graft copolymers were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, elemental analysis (EA), inductively coupled plasma (ICP), and differential scanning calorimetry (DSC). The second part of this research involved poly(dimethacrylate) dental restorative materials. Volumetric shrinkage during the cure of these resins results in a poor interface between the resin and the remaining tooth structure, limiting the lifetime of these materials. Cyclic anhydrides were incorporated into common monomer compositions used in dental applications. Volume expansion from the ring opening hydrolysis of these anhydrides was shown to be feasible. The modified dental resins were characterized by swelling, extraction and ultraviolet spectroscopy (UV), and density measurements. Linear poLymers designed to model the crosslinked dental resins were

  20. THE ALPHA/BETA-HYDROLASE FOLD

    NARCIS (Netherlands)

    OLLIS, DL; CHEAH, E; CYGLER, M; FROLOW, F; FRANKEN, SM; HAREL, M; REMINGTON, SJ; SILMAN, [No Value; SCHRAG, J; SUSSMAN, JL; VERSCHUEREN, KHG; GOLDMAN, A

    1992-01-01

    We have identified a new protein fold-the alpha/beta-hydrolase fold-that is common to several hydrolytic enzymes of widely differing phylogenetic origin and catalytic function. The core of each enzyme is similar: an alpha/beta-sheet, not barrel, of eight beta-sheets connected by alpha-helices. These

  1. The α/β hydrolase fold

    NARCIS (Netherlands)

    Ollis, David L.; Cheah, Eong; Cygler, Miroslaw; Dijkstra, Bauke; Frolow, Felix; Franken, Sybille M.; Harel, Michal; Remington, S. James; Silman, Israel; Schrag, Joseph; Sussman, Joel L.; Verschueren, Koen H.G.; Goldman, Adrian

    1992-01-01

    We have identified a new protein fold-the α/β hydrolase fold-that is common to several hydrolytic enzymes of widely differing phylogenetic origin and catalytic function. The core of each enzyme is similar: an α/β sheet, not barrel, of eight β-sheets connected by α-helices. These enzymes have diverge

  2. Nucleoside phosphorylation in amide solutions

    Science.gov (United States)

    Schoffstall, A. M.; Kokko, B.

    1978-01-01

    The paper deals with phosphorylation in possible prebiotic nonaqueous solvents. To this end, phosphorylation of nucleosides using inorganic phosphates in amide solutions is studied at room and elevated temperatures. Reaction proceeds most readily in formamide and N-methylformamide. Products obtained at elevated temperature are nucleotides, nucleoside 2',3'-cyclic phosphates, and when the phosphate concentration is high, nucleoside diphosphates. At room temperature, adenosine afforded a mixture of nucleotides, but none of the cyclic nucleotide. Conditions leading to the highest relative percentage of cyclic nucleotide involve the use of low concentrations of phosphate and an excess of nucleoside.

  3. Biocompatibility and degradation of aliphatic segmented poly(ester amide)s : in vitro and in vivo evaluation

    NARCIS (Netherlands)

    Lips, PAM; van Luyn, MJA; Chiellini, F; Brouwer, LA; Velthoen, IW; Dijkstra, PJ; Feijen, J

    2006-01-01

    Aliphatic segmented poly(ester amide)s, comprising a crystallizable amide phase and a flexible amorphous ester phase, were investigated for potential use in biomedical applications. By varying the amide content and the type of crystallizable amide segments, the polymer's thermal and mechanical prope

  4. N-Hydroxyimide Ugi Reaction toward α-Hydrazino Amides

    Science.gov (United States)

    2017-01-01

    The Ugi four-component reaction (U-4CR) with N-hydroxyimides as a novel carboxylic acid isostere has been reported. This reaction provides straightforward access to α-hydrazino amides. A broad range of aldehydes, amines, isocyanides and N-hydroxyimides were employed to give products in moderate to high yields. This reaction displays N–N bond formation by cyclic imide migration in the Ugi reaction. Thus, N-hydroxyimide is added as a new acid component in the Ugi reaction and broadens the scaffold diversity. PMID:28220702

  5. Synthesis and Quantitation of Six Phenolic Amides in Amaranthus spp

    DEFF Research Database (Denmark)

    Pedersen, Hans A; Steffensen, Stine Krogh; Christophersen, Carsten

    2010-01-01

    Cinnamoylphenethylamines are phenolic amides in which cinnamic acid provides the acid moiety and phenethylamine the amine moiety. Single ion monitoring (SIM) in LC-MS was performed on amaranth leaf extracts. Masses corresponding to sets of regioisomers, including previously reported compounds, we...

  6. Novel endogenous N-acyl amides activate TRPV1-4 receptors, BV-2 microglia, and are regulated in brain in an acute model of inflammation

    Directory of Open Access Journals (Sweden)

    Siham eRaboune

    2014-08-01

    Full Text Available A family of endogenous lipids, structurally analogous to the endogenous cannabinoid, N-arachidonoyl ethanolamine (Anandamide, and called N-acyl amides have emerged as a family of biologically active compounds at TRP receptors. N-acyl amides are constructed from an acyl group and an amine via an amide bond. This same structure can be modified by changing either the fatty acid or the amide to form potentially hundreds of lipids. More than 70 N-acyl amides have been identified in nature. We have ongoing studies aimed at isolating and characterizing additional members of the family of N-acyl amides in both central and peripheral tissues in mammalian systems. Here, using a unique in-house library of over 70 N-acyl amides we tested the following three hypotheses: 1 Additional N-acyl amides will have activity at TRPV1-4, 2 Acute peripheral injury will drive changes in CNS levels of N-acyl amides, and 3 N-acyl amides will regulate calcium in CNS-derived microglia. Through these studies, we have identified 20 novel N-acyl amides that collectively activate (stimulating or inhibiting TRPV1-4. Using lipid extraction and HPLC coupled to tandem mass spectrometry we showed that levels of at least 10 of these N-acyl amides that activate TRPVs are regulated in brain after intraplantar carrageenan injection. We then screened the BV2 microglial cell line for activity with this N-acyl amide library and found overlap with TRPV receptor activity as well as additional activators of calcium mobilization from these lipids. Together these data provide new insight into the family of N-acyl amides and their roles as signaling molecules at ion channels, in microglia, and in the brain in the context of inflammation.

  7. Tertiary Structure and Characterization of a Glycoside Hydrolase Family 44 Endoglucanase from Clostridium acetobutylicum▿ †

    OpenAIRE

    2009-01-01

    A gene encoding a glycoside hydrolase family 44 (GH44) protein from Clostridium acetobutylicum ATCC 824 was synthesized and transformed into Escherichia coli. The previously uncharacterized protein was expressed with a C-terminal His tag and purified by nickel-nitrilotriacetic acid affinity chromatography. Crystallization and X-ray diffraction to a 2.2-Å resolution revealed a triose phosphate isomerase (TIM) barrel-like structure with additional Greek key and β-sandwich folds, similar to othe...

  8. Beyond growth: novel functions for bacterial cell wall hydrolases.

    Science.gov (United States)

    Wyckoff, Timna J; Taylor, Jennifer A; Salama, Nina R

    2012-11-01

    The peptidoglycan cell wall maintains turgor pressure and cell shape of most bacteria. Cell wall hydrolases are essential, together with synthases, for growth and daughter cell separation. Recent work in diverse organisms has uncovered new cell wall hydrolases that act autonomously or on neighboring cells to modulate invasion of prey cells, cell shape, innate immune detection, intercellular communication, and competitor lysis. The hydrolases involved in these processes catalyze the cleavage of bonds throughout the sugar and peptide moities of peptidoglycan. Phenotypes associated with these diverse hydrolases reveal new functions of the bacterial cell wall beyond growth and division.

  9. Amide functionalized MWNT/SPEEK composite membrane for better electrochemical performance

    Science.gov (United States)

    Gahlot, Swati; Sharma, Prem P.; Kulshrestha, Vaibhav

    2016-05-01

    Nanocomposite membranes based on multiwalled carbon nanotube /SPEEK (sulfonated poly ether ether ketone) have been synthesized via simple solution casting. Prior to use CNT have been purified and grafted with carboxylic acid groups onto its walls by means of sulfuric and nitric acid. Afterwards, amidation of carboxylated CNTs (c-CNT) has been done. Amidated CNT (a-CNT) is then incorporated in SPEEK polymer matrix to synthesize nanocomposite membranes. Physicochemical, structural, thermal and mechanical characterizations are done through the respective techniques. Electric and ionic conductivities have also been evaluated. Composites membranes show the enhanced electrochemical performance with higher electric conductivity.

  10. Exported Epoxide Hydrolases Modulate Erythrocyte Vasoactive Lipids during Plasmodium falciparum Infection

    Directory of Open Access Journals (Sweden)

    Natalie J. Spillman

    2016-10-01

    Full Text Available Erythrocytes are reservoirs of important epoxide-containing lipid signaling molecules, including epoxyeicosatrienoic acids (EETs. EETs function as vasodilators and anti-inflammatory modulators in the bloodstream. Bioactive EETs are hydrolyzed to less active diols (dihydroxyeicosatrienoic acids by epoxide hydrolases (EHs. The malaria parasite Plasmodium falciparum infects host red blood cells (RBCs and exports hundreds of proteins into the RBC compartment. In this study, we show that two parasite epoxide hydrolases, P. falciparum epoxide hydrolases 1 (PfEH1 and 2 (PfEH2, both with noncanonical serine nucleophiles, are exported to the periphery of infected RBCs. PfEH1 and PfEH2 were successfully expressed in Escherichia coli, and they hydrolyzed physiologically relevant erythrocyte EETs. Mutations in active site residues of PfEH1 ablated the ability of the enzyme to hydrolyze an epoxide substrate. Overexpression of PfEH1 or PfEH2 in parasite-infected RBCs resulted in a significant alteration in the epoxide fatty acids stored in RBC phospholipids. We hypothesize that the parasite disruption of epoxide-containing signaling lipids leads to perturbed vascular function, creating favorable conditions for binding and sequestration of infected RBCs to the microvascular endothelium.

  11. Structural analysis of Clostridium acetobutylicum ATCC 824 glycoside hydrolase from CAZy family GH105

    Energy Technology Data Exchange (ETDEWEB)

    Germane, Katherine L., E-mail: katherine.germane.civ@mail.mil [Oak Ridge Associated Universities, 4692 Millennium Drive, Suite 101, Belcamp, MD 21017 (United States); Servinsky, Matthew D. [US Army Research Laboratory, 2800 Powder Mill Road, Adelphi, MD 20783 (United States); Gerlach, Elliot S. [Federal Staffing Resources, 2200 Somerville Road, Annapolis, MD 21401 (United States); Sund, Christian J. [US Army Research Laboratory, 2800 Powder Mill Road, Adelphi, MD 20783 (United States); Hurley, Margaret M., E-mail: katherine.germane.civ@mail.mil [US Army Research Laboratory, 4600 Deer Creek Loop, Aberdeen Proving Ground, MD 21005 (United States); Oak Ridge Associated Universities, 4692 Millennium Drive, Suite 101, Belcamp, MD 21017 (United States)

    2015-07-29

    The crystal structure of the protein product of the C. acetobutylicum ATCC 824 gene CA-C0359 is structurally similar to YteR, an unsaturated rhamnogalacturonyl hydrolase from B. subtilis strain 168. Substrate modeling and electrostatic studies of the active site of the structure of CA-C0359 suggests that the protein can now be considered to be part of CAZy glycoside hydrolase family 105. Clostridium acetobutylicum ATCC 824 gene CA-C0359 encodes a putative unsaturated rhamnogalacturonyl hydrolase (URH) with distant amino-acid sequence homology to YteR of Bacillus subtilis strain 168. YteR, like other URHs, has core structural homology to unsaturated glucuronyl hydrolases, but hydrolyzes the unsaturated disaccharide derivative of rhamnogalacturonan I. The crystal structure of the recombinant CA-C0359 protein was solved to 1.6 Å resolution by molecular replacement using the phase information of the previously reported structure of YteR (PDB entry (http://scripts.iucr.org/cgi-bin/cr.cgi?rm)) from Bacillus subtilis strain 168. The YteR-like protein is a six-α-hairpin barrel with two β-sheet strands and a small helix overlaying the end of the hairpins next to the active site. The protein has low primary protein sequence identity to YteR but is structurally similar. The two tertiary structures align with a root-mean-square deviation of 1.4 Å and contain a highly conserved active pocket. There is a conserved aspartic acid residue in both structures, which has been shown to be important for hydration of the C=C bond during the release of unsaturated galacturonic acid by YteR. A surface electrostatic potential comparison of CA-C0359 and proteins from CAZy families GH88 and GH105 reveals the make-up of the active site to be a combination of the unsaturated rhamnogalacturonyl hydrolase and the unsaturated glucuronyl hydrolase from Bacillus subtilis strain 168. Structural and electrostatic comparisons suggests that the protein may have a slightly different substrate

  12. Synthesis and Characterization of Poly(ether amide)s Containing Bisphthalazinone and Ether Linkages

    Institute of Scientific and Technical Information of China (English)

    Cheng LIU; Shou Hai ZHANG; Ming Jing WANG; Qi Zhen LIANG; Xi Gao JIAN

    2005-01-01

    A novel aromatic diacid, 4, 4'-bis[2-(4-carboxyphenyl)phthalazin-1-one-4-yl]-bisphenyl ether Ⅲ, containing bisphthalazinone and ether linkages was prepared from nucleophilic substitution of p-chlorobenzonitrile with the bisphenol-like monomer Ⅰ, followed by alkaline hydrolysis of the intermediate dinitrile Ⅱ. A series of poly(ether amide)s containing bisphthalazinone and ether linkages derived from diacid Ⅲ and aromatic diamines were synthesized by one-step solution condensation polymerization using triphenyl phosphite and pyridine as condensing agents. Moreover, the properties of poly(ether amide)s including thermal stability,solubility and crystallinity were also studied.

  13. Palladium-catalyzed Suzuki-Miyaura coupling of amides by carbon-nitrogen cleavage: general strategy for amide N-C bond activation.

    Science.gov (United States)

    Meng, Guangrong; Szostak, Michal

    2016-06-15

    The first palladium-catalyzed Suzuki-Miyaura cross-coupling of amides with boronic acids for the synthesis of ketones by sterically-controlled N-C bond activation is reported. The transformation is characterized by operational simplicity using bench-stable, commercial reagents and catalysts, and a broad substrate scope, including substrates with electron-donating and withdrawing groups on both coupling partners, steric-hindrance, heterocycles, halides, esters and ketones. The scope and limitations are presented in the synthesis of >60 functionalized ketones. Mechanistic studies provide insight into the catalytic cycle of the cross-coupling, including the first experimental evidence for Pd insertion into the amide N-C bond. The synthetic utility is showcased by a gram-scale cross-coupling and cross-coupling at room temperature. Most importantly, this process provides a blueprint for the development of a plethora of metal catalyzed reactions of typically inert amide bonds via acyl-metal intermediates. A unified strategy for amide bond activation to enable metal insertion into N-C amide bond is outlined ().

  14. Polymer amide in the Allende and Murchison meteorites

    Science.gov (United States)

    McGeoch, Julie E. M.; McGeoch, Malcolm W.

    2015-11-01

    It has been proposed that exothermic gas phase polymerization of amino acids can occur in the conditions of a warm dense molecular cloud to form hydrophobic polymer amide (HPA) (McGeoch and McGeoch 2014). In a search for evidence of this presolar chemistry Allende and Murchison meteorites and a volcano control were diamond burr-etched and Folch extracted for potential HPA yielding 85 unique peaks in the meteorite samples via matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI TOF/MS). The amino acids after acid hydrolysis in Allende were below the level of detection but many of the Allende peaks via the more sensitive MALDI/TOF analysis could be fitted to a polymer combination of glycine, alanine, and alpha-hydroxyglycine with high statistical significance. A similar significant fit using these three amino acids could not be applied to the Murchison data indicating more complex polymer chemistry.

  15. How amide hydrogens exchange in native proteins.

    Science.gov (United States)

    Persson, Filip; Halle, Bertil

    2015-08-18

    Amide hydrogen exchange (HX) is widely used in protein biophysics even though our ignorance about the HX mechanism makes data interpretation imprecise. Notably, the open exchange-competent conformational state has not been identified. Based on analysis of an ultralong molecular dynamics trajectory of the protein BPTI, we propose that the open (O) states for amides that exchange by subglobal fluctuations are locally distorted conformations with two water molecules directly coordinated to the N-H group. The HX protection factors computed from the relative O-state populations agree well with experiment. The O states of different amides show little or no temporal correlation, even if adjacent residues unfold cooperatively. The mean residence time of the O state is ∼100 ps for all examined amides, so the large variation in measured HX rate must be attributed to the opening frequency. A few amides gain solvent access via tunnels or pores penetrated by water chains including native internal water molecules, but most amides access solvent by more local structural distortions. In either case, we argue that an overcoordinated N-H group is necessary for efficient proton transfer by Grotthuss-type structural diffusion.

  16. Recombinant production of peptide C-terminal α-amides using an engineered intein

    DEFF Research Database (Denmark)

    Albertsen, Louise; Shaw, Allan C; Norrild, Jens Chr.;

    2013-01-01

    is that they contain a C-terminal that is α-amidated, and this amidation is crucial for biological function. A challenge is to generate such peptides by recombinant means and particularly in a production scale. Here, we have examined an intein-mediated approach to generate a PYY derivative in a larger scale. Initially...... of the 198 amino acid intein with an eight amino acid linker. The optimized intein construct was used to produce the PYY derivative under high cell density cultivation conditions, generating the peptide thioester precursor in good yields and subsequent amidation provided the target peptide......., we experienced challenges with hydrolysis of the intein fusion protein, which was reduced by a T3C mutation in the intein. Subsequently, we further engineered the intein to decrease the absolute size and improve the relative yield of the PYY derivative, which was achieved by substituting 54 residues...

  17. Alpha-amidated peptides derived from pro-opiomelanocortin in normal human pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Johnsen, A H

    1988-01-01

    Normal human pituitaries were extracted in boiling water and acetic acid, and the alpha-amidated peptide products of pro-opiomelanocortin (POMC), alpha-melanocyte-stimulating hormone (alpha MSH), gamma-melanocyte-stimulating hormone (gamma 1MSH), and amidated hinge peptide (HP-N), as well...... as their glycine-extended precursors, were characterized by sequence-specific radioimmunoassays, gel-chromatography, h.p.l.c. and amino acid sequencing. alpha MSH and gamma 1MSH constituted 0.27-1.32% and 0.10-5.10%, respectively, of the POMC-derived products [calculated as the sum of adrenocorticotropic hormone...... (ACTH)-(1-39), ACTH-(1-14) and alpha MSH immunoreactivity]. alpha MSH and ACTH-(1-14) were only present in non- or mono-acetylated forms. Only large forms of gamma 1MSH and gamma 2MSH were present in partly glycosylated states. The hinge peptides were amidated to an extent two to three orders...

  18. Structures of Highly Twisted Amides Relevant to Amide N-C Cross-Coupling: Evidence for Ground-State Amide Destabilization.

    Science.gov (United States)

    Pace, Vittorio; Holzer, Wolfgang; Meng, Guangrong; Shi, Shicheng; Lalancette, Roger; Szostak, Roman; Szostak, Michal

    2016-10-04

    Herein, we show that acyclic amides that have recently enabled a series of elusive transition-metal-catalyzed N-C activation/cross-coupling reactions are highly twisted around the N-C(O) axis by a new destabilization mechanism of the amide bond. A unique effect of the N-glutarimide substituent, leading to uniformly high twist (ca. 90°) irrespective of the steric effect at the carbon side of the amide bond has been found. This represents the first example of a twisted amide that does not bear significant steric hindrance at the α-carbon atom. The (15) N NMR data show linear correlations between electron density at nitrogen and amide bond twist. This study strongly supports the concept of amide bond ground-state twist as a blueprint for activation of amides toward N-C bond cleavage. The new mechanism offers considerable opportunities for organic synthesis and biological processes involving non-planar amide bonds.

  19. A novel and orally active poly(ADP-ribose) polymerase inhibitor, KR-33889 [2-[methoxycarbonyl(4-methoxyphenyl) methylsulfanyl]-1H-benzimidazole-4-carboxylic acid amide], attenuates injury in in vitro model of cell death and in vivo model of cardiac ischemia.

    Science.gov (United States)

    Oh, Kwang-Seok; Lee, Sunkyung; Yi, Kyu Yang; Seo, Ho Won; Koo, Hyun-Na; Lee, Byung Ho

    2009-01-01

    Blocking of poly(ADP-ribose) polymerase (PARP)-1 has been expected to protect the heart from ischemia-reperfusion injury. We have recently identified a novel and orally active PARP-1 inhibitor, KR-33889 [2-[methoxycarbonyl(4-methoxyphenyl)-methylsulfanyl]-1H-benzimidazole-4-carboxylic acid amide], and its major metabolite, KR-34285 [2-[carboxy(4-methoxyphenyl)methylsulfanyl]-1H-benzimidazole-4-carboxylic acid amide]. KR-33889 potently inhibited PARP-1 activity with an IC(50) value of 0.52 +/- 0.10 microM. In H9c2 myocardial cells, KR-33889 (0.03-30 microM) showed a resistance to hydrogen peroxide (2 mM)-mediated oxidative insult and significantly attenuated activation of intracellular PARP-1. In anesthetized rats subjected to 30 min of coronary occlusion and 3 h of reperfusion, KR-33889 (0.3-3 mg/kg i.v.) dose-dependently reduced myocardial infarct size. KR-34285, a major metabolite of KR-33889, exerted similar patterns to the parent compound with equi- or weaker potency in the same studies described above. In separate experiments for the therapeutic time window study, KR-33889 (3 mg/kg i.v.) given at preischemia, at reperfusion or in both, in rat models also significantly reduced the myocardial infarction compared with their respective vehicle-treated group. Furthermore, the oral administration of KR-33889 (1-10 mg/kg p.o.) at 1 h before occlusion significantly reduced myocardial injury. The ability of KR-33889 to inhibit PARP in the rat model of ischemic heart was confirmed by immunohistochemical detection of poly(ADP-ribose) activation. These results indicate that the novel PARP inhibitor KR-33889 exerts its cardioprotective effect in in vitro and in vivo studies of myocardial ischemia via potent PARP inhibition and also suggest that KR-33889 could be an attractive therapeutic candidate with oral activity for several cardiovascular disorders, including myocardial infarction.

  20. Fungal epoxide hydrolases: new landmarks in sequence-activity space.

    Science.gov (United States)

    Smit, Martha S

    2004-03-01

    Epoxide hydrolases are useful catalysts for the hydrolytic kinetic resolution of epoxides, which are sought after intermediates for the synthesis of enantiopure fine chemicals. The epoxide hydrolases from Aspergillus niger and from the basidiomycetous yeasts Rhodotorula glutinis and Rhodosporidium toruloides have demonstrated potential as versatile, user friendly biocatalysts for organic synthesis. A recombinant A. niger epoxide hydrolase, produced by an overproducing A. niger strain, is already commercially available and recombinant yeast epoxide hydrolases expressed in Escherichia coli have shown excellent results. Within the vast body of activity information on the one hand and gene sequence information on the other hand, the epoxide hydrolases from the Rhodotorula spp. and A. niger stand out because we have sequence information as well as activity information for both the wild-type and recombinant forms of these enzymes.

  1. Amide-induced phase separation of hexafluoroisopropanol-water mixtures depending on the hydrophobicity of amides.

    Science.gov (United States)

    Takamuku, Toshiyuki; Wada, Hiroshi; Kawatoko, Chiemi; Shimomura, Takuya; Kanzaki, Ryo; Takeuchi, Munetaka

    2012-06-21

    Amide-induced phase separation of hexafluoro-2-propanol (HFIP)-water mixtures has been investigated to elucidate solvation properties of the mixtures by means of small-angle neutron scattering (SANS), (1)H and (13)C NMR, and molecular dynamics (MD) simulation. The amides included N-methylformamide (NMF), N-methylacetamide (NMA), and N-methylpropionamide (NMP). The phase diagrams of amide-HFIP-water ternary systems at 298 K showed that phase separation occurs in a closed-loop area of compositions as well as an N,N-dimethylformamide (DMF) system previously reported. The phase separation area becomes wider as the hydrophobicity of amides increases in the order of NMF amides due to the hydrophobic interaction gives rise to phase separation of the mixtures. In contrast, the disruption of HFIP clusters causes the recovery of the homogeneity of the ternary systems. The present results showed that HFIP clusters are evolved with increasing amide content to the lower phase separation concentration in the same mechanism among the four amide systems. However, the disruption of HFIP clusters in the NMP and DMF systems with further increasing amide content to the upper phase separation concentration occurs in a different way from those in the NMF and NMA systems.

  2. Phases and phase transition in insoluble and adsorbed monolayers of amide amphiphiles: Specific characteristics of the condensed phases.

    Science.gov (United States)

    Vollhardt, D

    2015-08-01

    For understanding the role of amide containing amphiphiles in inherently complex biological processes, monolayers at the air-water interface are used as simple biomimetic model systems. The specific characteristics of the condensed phases and phase transition in insoluble and adsorbed monolayers of amide amphiphiles are surveyed to highlight the effect of the chemical structure of the amide amphiphiles on the interfacial interactions in model monolayers. The mesoscopic topography and/or two-dimensional lattice structures of selected amino acid amphiphiles, amphiphilic N-alkylaldonamide, amide amphiphiles with specific tailored headgroups, such as amide amphiphiles based on derivatized ethanolamine, e.g. acylethanolamines (NAEs) and N-,O-diacylethanolamines (DAEs) are presented. Special attention is devoted the dominance of N,O-diacylated ethanolamine in mixed amphiphilic acid amide monolayers. The evidence that a first order phase transition can occur in adsorption layers and that condensed phase domains of mesoscopic scale can be formed in adsorption layers was first obtained on the basis of the experimental characteristics of a tailored amide amphiphile. New thermodynamic and kinetic concepts for the theoretical description of the characteristics of amide amphiphile's monolayers were developed. In particular, the equation of state for Langmuir monolayers generalized for the case that one, two or more phase transitions occur, and the new theory for phase transition in adsorbed monolayers are experimentally confirmed at first by amide amphiphile monolayers. Despite the significant progress made towards the understanding the model systems, these model studies are still limited to transfer the gained knowledge to biological systems where the fundamental physical principles are operative in the same way. The study of biomimetic systems, as described in this review, is only a first step in this direction.

  3. Sequential backbone assignment based on dipolar amide-to-amide correlation experiments.

    Science.gov (United States)

    Xiang, ShengQi; Grohe, Kristof; Rovó, Petra; Vasa, Suresh Kumar; Giller, Karin; Becker, Stefan; Linser, Rasmus

    2015-07-01

    Proton detection in solid-state NMR has seen a tremendous increase in popularity in the last years. New experimental techniques allow to exploit protons as an additional source of information on structure, dynamics, and protein interactions with their surroundings. In addition, sensitivity is mostly improved and ambiguity in assignment experiments reduced. We show here that, in the solid state, sequential amide-to-amide correlations turn out to be an excellent, complementary way to exploit amide shifts for unambiguous backbone assignment. For a general assessment, we compare amide-to-amide experiments with the more common (13)C-shift-based methods. Exploiting efficient CP magnetization transfers rather than less efficient INEPT periods, our results suggest that the approach is very feasible for solid-state NMR.

  4. Sequential backbone assignment based on dipolar amide-to-amide correlation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, ShengQi; Grohe, Kristof; Rovó, Petra; Vasa, Suresh Kumar; Giller, Karin; Becker, Stefan; Linser, Rasmus, E-mail: rali@nmr.mpibpc.mpg.de [Max Planck Institute for Biophysical Chemistry, Department for NMR-Based Structural Biology (Germany)

    2015-07-15

    Proton detection in solid-state NMR has seen a tremendous increase in popularity in the last years. New experimental techniques allow to exploit protons as an additional source of information on structure, dynamics, and protein interactions with their surroundings. In addition, sensitivity is mostly improved and ambiguity in assignment experiments reduced. We show here that, in the solid state, sequential amide-to-amide correlations turn out to be an excellent, complementary way to exploit amide shifts for unambiguous backbone assignment. For a general assessment, we compare amide-to-amide experiments with the more common {sup 13}C-shift-based methods. Exploiting efficient CP magnetization transfers rather than less efficient INEPT periods, our results suggest that the approach is very feasible for solid-state NMR.

  5. Endogenous molecules stimulating N-acylethanolamine-hydrolyzing acid amidase (NAAA).

    Science.gov (United States)

    Tai, Tatsuya; Tsuboi, Kazuhito; Uyama, Toru; Masuda, Kim; Cravatt, Benjamin F; Houchi, Hitoshi; Ueda, Natsuo

    2012-05-16

    Fatty acid amide hydrolase (FAAH) plays the central role in the degradation of bioactive N-acylethanolamines such as the endocannabinoid arachidonoylethanolamide (anandamide) in brain and peripheral tissues. A lysosomal enzyme referred to as N-acylethanolamine-hydrolyzing acid amidase (NAAA) catalyzes the same reaction with preference to palmitoylethanolamide, an endogenous analgesic and neuroprotective substance, and is therefore expected as a potential target of therapeutic drugs. In the in vitro assays thus far performed, the maximal activity of NAAA was achieved in the presence of both nonionic detergent (Triton X-100 or Nonidet P-40) and the SH reagent dithiothreitol. However, endogenous molecules that might substitute for these synthetic compounds remain poorly understood. Here, we examined stimulatory effects of endogenous phospholipids and thiol compounds on recombinant NAAA. Among different phospholipids tested, choline- or ethanolamine-containing phospholipids showed potent effects, and 1 mM phosphatidylcholine increased NAAA activity by 6.6-fold. Concerning endogenous thiol compounds, dihydrolipoic acid at 0.1-1 mM was the most active, causing 8.5-9.0-fold stimulation. These results suggest that endogenous phospholipids and dihydrolipoic acid may contribute in keeping NAAA active in lysosomes. Even in the presence of phosphatidylcholine and dihydrolipoic acid, however, the preferential hydrolysis of palmitoylethanolamide was unaltered. We also investigated a possible compensatory induction of NAAA mRNA in brain and other tissues of FAAH-deficient mice. However, NAAA expression levels in all the tissues examined were not significantly altered from those in wild-type mice.

  6. Formation of amide bonds without a condensation agent and implications for origin of life.

    Science.gov (United States)

    Keller, M; Blöchl, E; Wächtershäuser, G; Stetter, K O

    1994-04-28

    Amide bonds are of central importance for biochemistry; in the guise of peptide bonds, they form the backbone of proteins. The formation of amide bonds without the assistance of enzymes poses a major challenge for theories of the origin of life. Enzyme-free formation of amide bonds between amino acids has been demonstrated in the presence of condensing agents such as cyanamide. Here we report the formation of amide bonds in aqueous solution in the absence of any condensing agent. We find that the formation of pyrite (FeS2) from FeS and H2S can provide the driving force for reductive acetylation of amino acids with mercaptoacetic acid (HSCH2COOH). The redox energy of pyrite formation permits the activation of the carboxylic acid group, which is converted to a species that reacts readily with amines. This process provides support for the chemo-autotrophic theory for the origin of life, in which pyrite formation supplies the energy source for the first autocatalytic reproduction cycle.

  7. Discovery of enantioselectivity of urea inhibitors of soluble epoxide hydrolase.

    Science.gov (United States)

    Manickam, Manoj; Pillaiyar, Thanigaimalai; Boggu, PullaReddy; Venkateswararao, Eeda; Jalani, Hitesh B; Kim, Nam-Doo; Lee, Seul Ki; Jeon, Jang Su; Kim, Sang Kyum; Jung, Sang-Hun

    2016-07-19

    Soluble epoxide hydrolase (sEH) hydrolyzes epoxyeicosatrienoic acids (EETs) in the metabolic pathway of arachidonic acid and has been considered as an important therapeutic target for chronic diseases such as hypertension, diabetes and inflammation. Although many urea derivatives are known as sEH inhibitors, the enantioselectivity of the inhibitors is not highlighted in spite of the stereoselective hydrolysis of EETs by sEH. In an effort to explore the importance of enantioselectivity in the urea scaffold, a series of enantiomers with the stereocenter adjacent to the urea nitrogen atom were prepared. The selectivity of enantiomers of 1-(α-alkyl-α-phenylmethyl)-3-(3-phenylpropyl)ureas showed wide range differences up to 125 fold with the low IC50 value up to 13 nM. The S-configuration with planar phenyl and small alkyl groups at α-position is crucial for the activity and selectivity. However, restriction of the free rotation of two α-groups with indan-1-yl or 1,2,3,4-tetrahydronaphthalen-1-yl moiety abolishes the selectivity between the enantiomers, despite the increase in activity up to 13 nM. The hydrophilic group like sulfonamido group at para position of 3-phenylpropyl motif of 1-(α-alkyl-α-phenylmethyl-3-(3-phenylpropyl)urea improves the activity as well as enantiomeric selectivity. All these ureas are proved to be specific inhibitor of sEH without inhibition against mEH.

  8. Naphthalene/quinoline amides and sulfonylureas as potent and selective antagonists of the EP4 receptor.

    Science.gov (United States)

    Burch, Jason D; Farand, Julie; Colucci, John; Sturino, Claudio; Ducharme, Yves; Friesen, Richard W; Lévesque, Jean-François; Gagné, Sébastien; Wrona, Mark; Therien, Alex G; Mathieu, Marie-Claude; Denis, Danielle; Vigneault, Erika; Xu, Daigen; Clark, Patsy; Rowland, Steve; Han, Yongxin

    2011-02-01

    Two new series of EP(4) antagonists based on naphthalene/quinoline scaffolds have been identified as part of our on-going efforts to develop treatments for inflammatory pain. One series contains an acidic sulfonylurea pharmacophore, whereas the other is a neutral amide. Both series show subnanomolar intrinsic binding potency towards the EP(4) receptor, and excellent selectivity towards other prostanoid receptors. While the amide series generally displays poor pharmacokinetic parameters, the sulfonylureas exhibit greatly improved profile. MF-592, the optimal compound from the sulfonylurea series, has a desirable overall preclinical profile that suggests it is suitable for further development.

  9. Preparation and evaluation of some amide ether carboxylate surfactants

    Directory of Open Access Journals (Sweden)

    M.M.A. El-Sukkary

    2012-06-01

    Full Text Available A homologous series of new mild surfactants, namely: Alkyl amide ether carboxylates surfactants (AEC RCO–NHCH2CH2O (CH2CH2O6CH2COONa, were synthesized by esterification, amidation, ethoxylation and carboxymethylation reaction steps of fatty acids (Lauric, Myristic, palmitic, stearic, oleic or linoleic. The chemical structures of the prepared compounds were confirmed using different spectroscopic techniques, FTIR spectroscopy, mass spectra and HNMR. The surface properties including surface and interfacial tensions, foaming height, emulsification power, calcium ion stability, stability to hydrolysis and critical micelle concentration (cmc were determined. The study of their surface properties showed their stability in hard water and in acidic and alkaline media. These compounds have high calcium ion stability. The low foaming power could have an application in the dyeing auxiliary industry. The lower values of the interfacial tension values indicate the ability of using these surfactants in several applications as corrosion inhibitors and biocides. The data revealed various advantages and potentials as a main surfactant as well as co- surfactants.

  10. Synthesis and characterization of ester and amide derivatives of titanium(IV) carboxymethylphosphonate

    Science.gov (United States)

    Melánová, Klára; Beneš, Ludvík; Trchová, Miroslava; Svoboda, Jan; Zima, Vítězslav

    2013-06-01

    A set of layered ester and amide derivatives of titanium(IV) carboxymethylphosphonate was prepared by solvothermal treatment of amorphous titanium(IV) carboxymethylphosphonate with corresponding 1-alkanols, 1,ω-alkanediols, 1-aminoalkanes, 1,ω-diaminoalkanes and 1,ω-amino alcohols and characterized by powder X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Whereas alkyl chains with one functional group form bilayers tilted to the layers, 1,ω-diaminoalkanes and most of 1,ω-alkanediols form bridges connecting the adjacent layers. In the case of amino alcohols, the alkyl chains form bilayer and either hydroxyl or amino group is used for bonding. This simple method for the synthesis of ester and amide derivatives does not require preparation of acid chloride derivative as a precursor or pre-intercalation with alkylamines and can be used also for the preparation of ester and amide derivatives of titanium carboxyethylphosphonate and zirconium carboxymethylphosphonate.

  11. The design, synthesis of amide KARI inhibitors and their biological activities

    Institute of Scientific and Technical Information of China (English)

    Baolei WANG; Yi MA; Yonghong LI; Suhua WANG; Zhengming LI

    2009-01-01

    Ketol-acid reductoisomerase(KARI) is a promising target for the design of herbicides yet there are only few reports on the molecular design of KARI inhibitors. In this paper, based on the reported 0.165 nm high resolution crystal structure of the spinach KARI complex, 279 molecules with low binding energy toward KARI were obtained from an MDL/ACD 3D database search using the program DOCK 4.0. According to the structural information of 279 molecules provided, some amide compounds have been designed and synthesized. The bioassay results show that most of these amides had inhibitory activity to rice KARI at a test concentration of 200 μg/mL. Among which eight amides, compounds 1 and 6 show 57.4% and 48.1% inhibitory activity to KARI. The herbicidal activities of these amides were further investigated on di-cotyledonous rape (Brassica campestris) and mono-cotyledonous bar-nyardgrass (Echinochloa crusgalli). Compounds 1 and 6 were more favorable than others and showed 52.0% and 72.6% inhibitory activity on rape root at 100 μg/mL concentration, respectively. These amides could be further optimized for finding more potent candidates.

  12. Polyimides Containing Amide And Perfluoroisopropyl Links

    Science.gov (United States)

    Dezem, James F.

    1993-01-01

    New polyimides synthesized from reactions of aromatic hexafluoroisopropyl dianhydrides with asymmetric amide diamines. Soluble to extent of at least 10 percent by weight at temperature of about 25 degrees C in common amide solvents such as N-methylpyrrolidone, N,N-dimethylacetamide, and N,N-dimethylformamide. Polyimides form tough, flexible films, coatings, and moldings. Glass-transition temperatures ranged from 300 to 365 degrees C, and crystalline melting temperatures observed between 543 and 603 degrees C. Display excellent physical, chemical, and electrical properties. Useful as adhesives, laminating resins, fibers, coatings for electrical and decorative purposes, films, wire enamels, and molding compounds.

  13. A simplified electrostatic model for hydrolase catalysis.

    Science.gov (United States)

    Pessoa Filho, Pedro de Alcantara; Prausnitz, John M

    2015-07-01

    Toward the development of an electrostatic model for enzyme catalysis, the active site of the enzyme is represented by a cavity whose surface (and beyond) is populated by electric charges as determined by pH and the enzyme's structure. The electric field in the cavity is obtained from electrostatics and a suitable computer program. The key chemical bond in the substrate, at its ends, has partial charges with opposite signs determined from published force-field parameters. The electric field attracts one end of the bond and repels the other, causing bond tension. If that tension exceeds the attractive force between the atoms, the bond breaks; the enzyme is then a successful catalyst. To illustrate this very simple model, based on numerous assumptions, some results are presented for three hydrolases: hen-egg white lysozyme, bovine trypsin and bovine ribonuclease. Attention is given to the effect of pH.

  14. Amide-transforming activity of Streptomyces: possible application to the formation of hydroxy amides and aminoalcohols.

    Science.gov (United States)

    Yamada, Shinya; Miyagawa, Taka-Aki; Yamada, Ren; Shiratori-Takano, Hatsumi; Sayo, Noboru; Saito, Takao; Takano, Hideaki; Beppu, Teruhiko; Ueda, Kenji

    2013-07-01

    To develop an efficient bioconversion process for amides, we screened our collection of Streptomyces strains, mostly obtained from soil, for effective transformers. Five strains, including the SY007 (NBRC 109343) and SY435 (NBRC 109344) of Streptomyces sp., exhibited marked conversion activities from the approximately 700 strains analyzed. These strains transformed diverse amide compounds such as N-acetyltetrahydroquinoline, N-benzoylpyrrolidine, and N-benzoylpiperidine into alcohols or N,O-acetals with high activity and regioselectivity. N,O-acetal was transformed into alcohol by serial tautomerization and reduction reactions. As such, Streptomyces spp. can potentially be used for the efficient preparation of hydroxy amides and aminoalcohols.

  15. Synthesis and characterization of poly(ester amide from remewable resources through melt polycondensation

    Directory of Open Access Journals (Sweden)

    B. B. Wang

    2014-01-01

    Full Text Available Biodegradable poly(ester amides (PEAs were synthesized from lactic acid and 11-aminoundecanoic acid via melt polycondensation. Molecular weights, chemical structures and thermal properties of the poly(ester amides were characterized in terms of gel permeation chromatography (GPC, Fourier transform infrared spectroscopy (FTIR, 1H nuclear magnetic resonance (1H NMR, differential scanning calorimetry (DSC and thermogravimetric analysis (TGA, respectively. The PEAs have low molecular weights and display a lower cold crystallization temperature as well as smaller crystallinity by comparison with the pure poly(lactic acid (PLA. The incorporation of the 11-aminoundecanoic acid into the PLA chain not only improved the thermal stability but changed the decomposition process.

  16. Variation of protein backbone amide resonance by electrostatic field

    OpenAIRE

    Sharley, John N.

    2015-01-01

    Amide resonance is found to be sensitive to electrostatic field with component parallel or antiparallel the amide C-N bond. This effect is linear and without threshold in the biologically plausible electrostatic field range -0.005 to 0.005 au. Variation of amide resonance varies Resonance-Assisted Hydrogen Bonding such as occurs in the hydrogen bonded chains of backbone amides of protein secondary structures such as beta sheet and alpha helix, varying the stability of the secondary structure....

  17. Molecular Cloning of a Novel cDNA From Mus Muscular BALB/c Mice Encoding Glycosyl Hydrolase Family 1: A Homolog of HumanLactase-Phlorizin Hydrolase

    Institute of Scientific and Technical Information of China (English)

    WEI HE; ZHEN-YU JI; CHENG-YU HUANG

    2006-01-01

    Objective To study the mechanism of lactose intolerance (LI) by cloning the mouse lactase cDNA and recombining a vector. Methods Total murine RNA was isolated from the small intestine of a 4-week-old BALB/c mouse (♂).Gene-specific primers were designed and synthesized according to the cDNA sequences of lactase-phlorizin hydrolase (LPH) in human, rat, and rabbit. A coding sequence (CDS) fragment was obtained using RT-PCR, and inserted into a clone vector pNEB-193, then the cDNA was sequenced and analyzed using bioinformatics. Results The cDNA from the BALB/c mouse with 912 bp encoding 303 amino acid residues. Analysis of the deduced amino acid sequence using bioinformatics revealed that this cDNA shared extensive sequence homology with human LPH containing a conserved glycosy1 hydrolase family 1 motif important for regulating lactase intolerance. Conclusion BALB/c mouse LPH cDNA (GenBank accession No: AY751548) provides a necessary foundation for study of the biological function and regulatory mechanism of the lactose intolerance in mice.

  18. Efficient Amide Based Halogenide Anion Receptors

    Institute of Scientific and Technical Information of China (English)

    Hong Xing WU; Feng Hua LI; Hai LIN; Shou Rong ZHU; Hua Kuan LIN

    2005-01-01

    In this paper, we present the synthesis and anion recognition properties of the amide based phenanthroline derivatives 1, 2 and 3. In all cases 1:1 receptor: anion complexes were observed. The receptors were found to be selective for fluoride and chloride respectively over other putative anionic guest species.

  19. ACRYLATE-AMIDE FOAM CARDIOVASCULAR PROSTHESES.

    Science.gov (United States)

    thoracic and abdominal aorta. The use of a composite construction utilizing acrylate-amide foam is being evaluated in prostheses for mitral valve ...bleeding. The success of the initial experimental work has led to a clinical trial in which 99 replacement , bypass, or patch-angioplasty procedures... replacement , superior vena cava patch venoplasty, and esophageal replacement . (Author)

  20. Platinum catalysed hydrolytic amidation of unactivated nitriles

    NARCIS (Netherlands)

    Cobley, Christopher J.; Heuvel, Marco van den; Abbadi, Abdelilah; Vries, Johannes G. de

    2000-01-01

    The platinum(II) complex, [(Me2PO··H··OPMe2)PtH(PMe2OH)], efficiently catalyses the direct conversion of unactivated nitriles to N-substituted amides with both primary and secondary amines. Possible mechanisms for this reaction are discussed and evidence for initial amidine formation is reported. Is

  1. Expression of Nudix hydrolase genes in barley under UV irradiation

    Science.gov (United States)

    Tanaka, Sayuri; Sugimoto, Manabu; Kihara, Makoto

    Seed storage and cultivation should be necessary to self-supply foods when astronauts would stay and investigate during long-term space travel and habitation in the bases on the Moon and Mars. Thought the sunlight is the most importance to plants, both as the ultimate energy source and as an environmental signal regulating growth and development, UV presenting the sunlight can damage many aspects of plant processes at the physiological and DNA level. Especially UV-C, which is eliminated by the stratospheric ozone layer, is suspected to be extremely harmful and give a deadly injury to plants in space. However, the defense mechanism against UV-C irradiation damage in plant cells has not been clear. In this study, we investigated the expression of Nudix hydrolases, which defense plants from biotic / abiotic stress, in barley under UV irradiation. The genes encoding the amino acid sequences, which show homology to those of 28 kinds of Nudix hydrolases in Arabidopsis thaliana, were identified in the barley full-length cDNA library. BLAST analysis showed 14 kinds of barley genes (HvNUDX1-14), which encode the Nudix motif sequence. A phylogenetic tree showed that HvNUDX1, HvNUDX7, HvNUDX9 and HvNUDX11 belonged to the ADP-ribose pyrophosphohydrolase, ADP-sugar pyrophosphohydrolase, NAD(P)H pyrophosphohydrolase and FAD pyrophosphohydrolase subfamilies, respectively, HvNUDX3, HvNUDX6, and HvNUDX8 belonged to the Ap _{n}A pyrophosphohydrolase subfamilies, HvNUDX5 and HvNUDX14 belonged to the coenzyme A pyrophosphohydrolase subfamilies, HvNUDX12 and HvNUDX13 belonged to the Ap _{4}A pyrophosphohydrolase subfamilies. Induction of HvNUDX genes by UV-A (340nm), UV-B (312nm), and UV-C (260nm) were analyzed by quantitative RT-PCR. The results showed that HvNUDX4 was induced by UV-A and UV-B, HvNUDX6 was induced by UV-B and UV-C, and HvNUDX7 and HvNUDX14 were induced by UV-C, significantly. Our results suggest that the response of HvNUDXs to UV irradiation is different by UV

  2. Carboxylic ester hydrolases in mitochondria from rat skeletal muscle

    DEFF Research Database (Denmark)

    Kirkeby, S; Moe, D; Zelander, T

    1990-01-01

    A mitochondrial pellet, prepared from rat skeletal muscle, contained a number of carboxylic ester hydrolase isoenzymes. The esterases which split alpha-naphthyl acetate were organophosphate sensitive, whereas two out of three indoxyl acetate hydrolysing enzymes were resistant to both organophosph......A mitochondrial pellet, prepared from rat skeletal muscle, contained a number of carboxylic ester hydrolase isoenzymes. The esterases which split alpha-naphthyl acetate were organophosphate sensitive, whereas two out of three indoxyl acetate hydrolysing enzymes were resistant to both...

  3. Effects of indole amides on lettuce and onion germination and growth.

    Science.gov (United States)

    Borgati, Thiago F; Boaventura, Maria Amelia D

    2011-01-01

    Auxins, such as indole-3-acetic acid (IAA), are important in plant germination and growth, while physiological polyamines, such as putrescine, are involved in cell proliferation and differentiation, and their concentrations increase during germination. In this work, novel indole amides were synthesized in good yields by monoacylation of morpholine and unprotected symmetrical diamines with indole-3-carboxylic acid, a putative metabolite of IAA, possessing no auxin-like activity. These amides were tested for their effects on seed germination and growth of the radicles and shoots of Lactuca sativa (lettuce) and Allium cepa (onion) seedlings, at 100.0, 1.0, and 0.01 microM concentrations. Germination was generally stimulated, with the exception of amide 3, derived from morpholine, at 100 microM. On radicle and shoot growth, the effect of these compounds was predominantly inhibitory. Compound 3 was the best inhibitor of growth of lettuce and onion, at the highest concentration. Amides, such as propanil, among others, are described as having herbicidal activity.

  4. Chlorination of N-methylacetamide and amide-containing pharmaceuticals. Quantum-chemical study of the reaction mechanism.

    Science.gov (United States)

    Šakić, Davor; Šonjić, Pavica; Tandarić, Tana; Vrček, Valerije

    2014-03-27

    Chlorination of amides is of utmost importance in biochemistry and environmental chemistry. Despite the huge body of data, the mechanism of reaction between amides and hypochlorous acid in aqueous environment remains unclear. In this work, the three different reaction pathways for chlorination of N-methylacetamide by HOCl have been considered: the one-step N-chlorination of the amide, the chlorination via O-chlorinated intermediate, and the N-chlorination of the iminol intermediate. The high-level quantum chemical G3B3 composite procedure, double-hybrid B2-PLYPD, B2K-PLYP methods, and global hybrid M06-2X and BMK methods have been employed. The calculated energy barriers have been compared to the experimental value of ΔG(#)298 ≈ 87 kJ/mol, which corresponds to reaction rate constant k(r) ≈ 0.0036 M(-1) s(-1). Only the mechanism in which the iminol form of N-methylacetamide reacts with HOCl is consistent (ΔG(#)298 = 87.3 kJ/mol at G3B3 level) with experimental results. The analogous reaction mechanism has been calculated as the most favorable pathway in the chlorination of small-sized amides and amide-containing pharmaceuticals: carbamazepine, acetaminophen, and phenytoin. We conclude that the formation of the iminol intermediate followed by its reaction with HOCl is the general mechanism of N-chlorination for a vast array of amides.

  5. Inhibition of soluble epoxide hydrolase modulates inflammation and autophagy in obese adipose tissue and liver: Role for omega-3 epoxides

    OpenAIRE

    López-Vicario, Cristina; Alcaraz-Quiles, José; García-Alonso, Verónica; Rius, Bibiana; Hwang, Sung H.; Titos, Esther; Lopategi, Aritz; Hammock, Bruce D.; Arroyo, Vicente; Clària, Joan

    2014-01-01

    Our study demonstrates that stabilization of cytochrome P-450 epoxides derived from omega-3 polyunsaturated fatty acids through inhibition of the inactivating enzyme soluble epoxide hydrolase (sEH) exerts beneficial actions in counteracting metabolic disorders associated with obesity. In addition, our study sheds more light on the role of sEH in cellular homeostasis by providing evidence that omega-3 epoxides and sEH inhibition regulate autophagy and endoplasmic reticulum stress in insulin-se...

  6. Molecular cloning, expression and characterization of acylpeptide hydrolase in the silkworm, Bombyx mori.

    Science.gov (United States)

    Fu, Ping; Sun, Wei; Zhang, Ze

    2016-04-10

    Acylpeptide hydrolase (APH) can catalyze the release of the N-terminal amino acid from acetylated peptides. There were many documented examples of this enzyme in various prokaryotic and eukaryotic organisms. However, knowledge about APH in insects still remains unknown. In this study, we cloned and sequenced a putative silkworm Bombyx mori APH (BmAPH) gene. The BmAPH gene encodes a protein of 710 amino acids with a predicted molecular mass of 78.5kDa. The putative BmAPH and mammal APHs share about 36% amino acid sequence identity, yet key catalytic residues are conserved (Ser566, Asp654, and His686). Expression and purification of the recombinant BmAPH in Escherichia coli showed that it has acylpeptide hydrolase activity toward the traditional substrate, Ac-Ala-pNA. Furthermore, organophosphorus (OP) insecticides, chlorpyrifos, phoxim, and malathion, significantly inhibited the activity of the APH both in vitro and in vivo. In addition, BmAPH was expressed in all tested tissues and developmental stages of the silkworm. Finally, immunohistochemistry analysis showed that BmAPH protein was localized in the basement membranes. These results suggested that BmAPH may be involved in enhancing silkworm tolerance to the OP insecticides. In a word, our results provide evidence for understanding of the biological function of APH in insects.

  7. An amidated carboxymethylcellulose hydrogel for cartilage regeneration.

    Science.gov (United States)

    Leone, Gemma; Fini, Milena; Torricelli, Paola; Giardino, Roberto; Barbucci, Rolando

    2008-08-01

    An amidic derivative of carboxymethylcellulose was synthesized (CMCA). The new polysaccharide was obtained by converting a large percentage of carboxylic groups ( approximately 50%) of carboxymethylcellulose into amidic groups rendering the macromolecule quite similar to hyaluronan. Then, the polysaccharide (CMCA) was crosslinked. The behavior of CMCA hydrogel towards normal human articular chondrocytes (NHAC) was in vitro studied monitoring the cell proliferation and synthesis of extra cellular matrix (ECM) components and compared with a hyaluronan based hydrogel (Hyal). An extracellular matrix rich in cartilage-specific collagen and proteoglycans was secreted in the presence of hydrogels. The injectability of the new hydrogels was also analysed. An experimental in vivo model was realized to study the effect of CMCA and Hyal hydrogels in the treatment of surgically created partial thickness chondral defects in the rabbit knee. The preliminary results pointed out that CMCA hydrogel could be considered as a potential compound for cartilage regeneration.

  8. Interacting Blends of Novel Unsaturated Polyester Amide Resin with Styrene

    Directory of Open Access Journals (Sweden)

    Hasmukh S. Patel

    2004-01-01

    Full Text Available Novel unsaturated poly (ester-amide resins (UPEAs were prepared by the reaction between an epoxy resin, namely diglycidyl ether of bisphenol–A (DGEBA and unsaturated aliphatic bisamic acids using a base catalyst. These UPEAs were then blended with a vinyl monomer namely, Styrene (STY. to produce a homogeneous resin syrup. The curing of these UPEAs-STY. resin blends was carried out by using benzoyl peroxide (BPO as a catalyst and was monitored by using a differential scanning calorimeter (DSC. The glass fibre reinforced composites (i.e. laminates of these UPEA-STY. resin blends were fabricated using the DSC data. The chemical, mechanical and electrical properties of the glass fibre composites have also been evaluated. The unreinforced cured samples of the UPEA-STY. resin blends were also analyzed by thermogravimetry (TGA.

  9. Amide-based Fluorescent Macrocyclic Anion Receptors

    Institute of Scientific and Technical Information of China (English)

    ZENG, Zhen-Ya(曾振亚); XU, Kuo-Xi(徐括喜); HE, Yong-Bing(何永炳); LIU, Shun-Ying(刘顺英); WU, Jin-Long(吴进龙); WEI, Lan-Hua(隗兰华); MENG, Ling-Zhi(孟令芝)

    2004-01-01

    Two fluorescent anion receptors (1 and 2) based on amide macrocycle were synthesized and corresponding fluorescence quenching induced by anion complexation was observed in different degree. Receptors form 1: 1 complexes with anions by hydrogen bonding interactions. Receptor 1 bound anions in the order of F->Cl->H2PO4->CH3COO->>Br-, I- and receptor 2 showed high selectivity to F- over other anions.

  10. Polyimides containing amide and perfluoroisopropylidene connecting groups

    Science.gov (United States)

    Dezern, James F. (Inventor)

    1993-01-01

    New, thermooxidatively stable polyimides were prepared from the reaction of aromatic dianhydrides containing isopropylidene bridging groups with aromatic diamines containing amide connecting groups between the rings. Several of these polyimides were shown to be semi-crystalline as evidenced by wide angle x ray scattering and differential scanning calorimetry. Most of the polyimides form tough, flexible films with high tensile properties. These polyimide films exhibit enhanced solubility in organic solvents.

  11. Protein topology determines cysteine oxidation fate: the case of sulfenyl amide formation among protein families.

    Science.gov (United States)

    Defelipe, Lucas A; Lanzarotti, Esteban; Gauto, Diego; Marti, Marcelo A; Turjanski, Adrián G

    2015-03-01

    Cysteine residues have a rich chemistry and play a critical role in the catalytic activity of a plethora of enzymes. However, cysteines are susceptible to oxidation by Reactive Oxygen and Nitrogen Species, leading to a loss of their catalytic function. Therefore, cysteine oxidation is emerging as a relevant physiological regulatory mechanism. Formation of a cyclic sulfenyl amide residue at the active site of redox-regulated proteins has been proposed as a protection mechanism against irreversible oxidation as the sulfenyl amide intermediate has been identified in several proteins. However, how and why only some specific cysteine residues in particular proteins react to form this intermediate is still unknown. In the present work using in-silico based tools, we have identified a constrained conformation that accelerates sulfenyl amide formation. By means of combined MD and QM/MM calculation we show that this conformation positions the NH backbone towards the sulfenic acid and promotes the reaction to yield the sulfenyl amide intermediate, in one step with the concomitant release of a water molecule. Moreover, in a large subset of the proteins we found a conserved beta sheet-loop-helix motif, which is present across different protein folds, that is key for sulfenyl amide production as it promotes the previous formation of sulfenic acid. For catalytic activity, in several cases, proteins need the Cysteine to be in the cysteinate form, i.e. a low pKa Cys. We found that the conserved motif stabilizes the cysteinate by hydrogen bonding to several NH backbone moieties. As cysteinate is also more reactive toward ROS we propose that the sheet-loop-helix motif and the constraint conformation have been selected by evolution for proteins that need a reactive Cys protected from irreversible oxidation. Our results also highlight how fold conservation can be correlated to redox chemistry regulation of protein function.

  12. The influence of ferric (III citrate on ATP-hydrolases of Desulfuromonas acetoxidans ІМV В-7384

    Directory of Open Access Journals (Sweden)

    O. Maslovska

    2013-02-01

    peroxidation products in bacterial cells confirms free radical mechanism of oxidation of polyunsaturated fatty acids. Thus, for fulfiling complete analyses of cell response against oxidative stress it was reasonable to investigate the influence of ferric (III citrate on specific ATP-hydrolase activity, Na+, K+-ATP-hydrolase activity and Mg2+-ATP-hydrolase activity of D. acetoxidans ІМV В-7384. Bacteria were cultivated in the modified Postgaite C medium during four days under the anaerobic conditions and temperature +27°С with addition from 10 to 20 mM of ferric (III citrate into the growth medium. Control samples didn’t contain investigated metal salt. Chosen concentrations of metal salt caused inhibition of bacterial growth by 20–50%. Activities of ATP-hydrolases were investigated as described. It was shown, that specific ATP-hydrolase activity of D. acetoxidans ІМV В-7384 is changing in dependance on duration of ferric (III citrate exposure and concentration of the metal salt. Addition of the ferric (III citrate in relatively low concentrations (10–12 mM causes increasing of specific ATP-hydrolase activity of D. acetoxidans IMV B-7384 in comparison with control. Activity of investigated enzymes was inhibited under the increasing of metal salt concentration in bacterial growth medium. Increase of duration of D. acetoxidans IMV B-7384 cultivation causes decrease of ATP-hydrolase activity. Addition of ferric (III citrate causes simultaneous increasing of Na+, K+-ATP-hydrolase activity and inhibition of Mg2+-ATP-hydrolase activity during four days of bacterial cultivation.

  13. Synthesis, characterization and pharmacological evaluation of amide prodrugs of Flurbiprofen

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Ashutosh; Veerasamy, Ravichandran; Jain, Prateek Kumar; Dixit, Vinod Kumar; Agrawal, Ram Kishor [Dr. H. S. Gour Vishwavidyalaya, Sagar (India). Dept. of Pharmaceutical Sciences. Pharmaceutical Chemistry Research Lab.]. E-mail: dragrawal2001@yahoo.co.in

    2008-07-01

    Flurbiprofen (FB) suffers from the general side effects of NSAIDs, owing to presence of free carboxylic acid group. The study was aimed to retard the adverse effects of gastrointestinal origin. Ten prodrugs of FB were synthesized by amidation with ethyl esters of amino acids, namely, glycine, L-phenylalanine, L-tryptophan, L-valine, L-isoleucine, L-alanine, L-leucine, L-glutamic acid, L-aspartic acid and {beta} alanine. Purified synthesized prodrugs were characterized by m.p., TLC, solubility, partition coefficients, elemental analyses, UV, FTIR, NMR and MS. Synthesized prodrugs were subjected for bioavailability studies, analgesic, anti-inflammatory activities and ulcerogenic index. Marked reduction of ulcerogenic index and comparable analgesic, antiinflammatory activities were obtained in all cases as compared to FB. Among synthesized prodrugs AR-9, AR-10 and AR-2 showing excellent pharmacological response and encouraging hydrolysis rate both in (Simulated Intestinal Fluid) SIF and in 80% human plasma. Prodrugs with increased aliphatic side chain length or introduction of aromatic substituent resulted in enhanced partition coefficient but diminished dissolution and hydrolysis rate. Such prodrugs can be considered for sustained release purpose. (author)

  14. Kinetic Study of the Reaction of the Phthalimide-N-oxyl Radical with Amides: Structural and Medium Effects on the Hydrogen Atom Transfer Reactivity and Selectivity.

    Science.gov (United States)

    Bietti, Massimo; Forcina, Veronica; Lanzalunga, Osvaldo; Lapi, Andrea; Martin, Teo; Mazzonna, Marco; Salamone, Michela

    2016-12-02

    A kinetic study of the hydrogen atom transfer (HAT) reactions from a series of secondary N-(4-X-benzyl)acetamides and tertiary amides to the phthalimide-N-oxyl radical (PINO) has been carried out. The results indicate that HAT is strongly influenced by structural and medium effects; in particular, the addition of Brønsted and Lewis acids determines a significant deactivation of C-H bonds α to the amide nitrogen of these substrates. Thus, by changing the reaction medium, it is possible to carefully control the regioselectivity of the aerobic oxidation of amides catalyzed by N-hydroxyphthalimide, widening the synthetic versatility of this process.

  15. NCBI nr-aa BLAST: CBRC-MEUG-01-1177 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MEUG-01-1177 pdb|2VYA|A Chain A, Crystal Structure Of Fatty Acid Amide Hydrolase Conjugated... With The Drug-Like Inhibitor Pf-750 pdb|2VYA|B Chain B, Crystal Structure Of Fatty Acid Amide Hydrolase Conjugated With The Drug-Like Inhibitor Pf-750 2VYA 2e-26 79% ...

  16. The effect of dietary rape-seed oil on cholesterol-ester metabolism and cholesterol-ester-hydrolase activity in the rat adrenal.

    Science.gov (United States)

    Beckett, G J; Boyd, G S

    1975-05-06

    The effects of stock diet and stock diet supplemented by olive oil and rape seed on rat adrenal cholesterol ester metabolism have been studied. Rats fed rape seed oil failed to gain weight at the same rate as rats fed olive oil. A prominent feature of the rats fed rape seed oil was an accumulation of high concentrations of cholesterol erucate in the adrenal lipid droplets. When these rats were subjected to an ether stress no percentage decrease in the amount of cholesterol erucate was observed. Adrenal cholesterol ester hydrolase activity was higher in rats fed the olive oil and rape seed oil diets than rats fed the stock diet. In rats fed stock or olive oil diets, a ten-minute ether anaesthesia stress resulted in a two-fold increase in activity of adrenal cholesterol ester hydrolase. Cofactor addition of ATP, cyclic AMP and MgCl-2 in vitro resulted in a stimulation of cholesterol ester hydrolase to a similar activity in both quiescent and ether-stressed rats. By contrast rats fed the rape seed oil diet gave no significant stimulation of cholesterol ester hydrolase activity when given an ether stress or when cofactors were added in vitro. Cholesterol erucate was hydrolysed at only 25% to 30% of the rate of cholesterol oleate in vitro in all groups of animals. Oleic acid added in vitro gave an inhibition of cholesterol ester hydrolase activity in rats fed stock diet while erucic acid activated the enzyme. The accumulation of cholesterol erucate in the adrenal when rats are fed rape seed oil could be due to the reduced ability of cholesterol ester hydrolase to hydrolyse this ester.

  17. Synthesis and Evaluation of Coumaroyl Dipeptide Amide as Potential Whitening Agents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jaeil; Lee, Jaeho [Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of); Lee, Hyesuk; Shin, Kyonghoon; Ryu, Geunseog; Cho, Inshik; Kim, Hanyoung [Central Research Laboratories, Daejeon (Korea, Republic of)

    2013-10-15

    Coumaroyl dipeptide amide, Coumaric acid-LG-NH{sub 2}, was prepared successfully using the solid-phase method, and its efficacy as a skin whitening agent was studied. Coumaric acid-LG-NH{sub 2} was prepared with Rink-amide resin, and 96.354% of purity was obtained. Using MTT assay and LDH release assay, we found that it exhibited very low cytotoxicity. And, we found that Coumaric acid-LG-NH{sub 2} inhibited tyrosinase activity dose-dependently and showed superior tyrosinase inhibitory activity to well-known whitening agent, arbutin. IC{sub 50} value of Coumaric acid-LG-NH{sub 2} was 182.4 μM, and IC{sub 50} value of arbutin was 384.6 μM. Also, in measurement of melanin contents using B16F1 melanoma cell lines, Coumaric acid-LG-NH{sub 2} reduced melanin production induced by α-MSH statistically significant, and showed superior melanin inhibitory activity to p-coumaric acid or arbutin. In addition, Coumaric acid-LG-NH{sub 2} reduced MC1R mRNA expression level. Thus, we concluded that MC1R pathway is the significant pathway of Coumaric acid-LG-NH{sub 2}, and Coumaric acid-LG-NH{sub 2} has great potential to be used as novel whitening agents.

  18. Chemical constituents from red algae Bostrychia radicans (Rhodomelaceae): new amides and phenolic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Ana Ligia Leandrini de; Silva, Denise B. da; Lopes, Norberto P.; Debonsi, Hosana M. [Universidade de Sao Paulo (FCFRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Ciencias Farmaceuticas de Ribeirao Preto. Dept. de Quimica e Fisica; Yokoya, Nair S., E-mail: hosana@fcfrp.usp.br [Instituto de Botanica, Sao Paulo, SP (Brazil). Secao de Ficologia

    2012-07-01

    This study describes the isolation and structural determination of two amides, isolated for the first time: N,4-dihydroxy-N-(2'-hydroxyethyl)-benzamide (0.019%) and N,4-dihydroxy-N-(2'-hydroxyethyl)-benzeneacetamide (0.023%). These amides, produced by the red macroalgae Bostrychia radicans, had their structures assigned by NMR spectral data and MS analyses. In addition, this chemical study led to the isolation of cholesterol, heptadecane, squalene, trans-phytol, neophytadiene, tetradecanoic and hexadecanoic acids, methyl hexadecanoate and methyl 9-octadecenoate, 4-(methoxymethyl)-phenol, 4-hydroxybenzaldehyde, methyl 4-hydroxybenzeneacetate, methyl 2-hydroxy-3-(4-hydroxyphenyl)-propanoate, hydroquinone, methyl 4-hydroxymandelate, methyl 4-hydroxybenzoate, 4-hydroxybenzeneacetic acid and (4-hydroxyphenyl)-oxo-acetaldehyde. This is the first report concerning these compounds in B. radicans, contributing by illustrating the chemical diversity within the Rhodomelaceae family. (author)

  19. Chemical constituents from red algae Bostrychia radicans (Rhodomelaceae: new amides and phenolic compounds

    Directory of Open Access Journals (Sweden)

    Ana Lígia Leandrini de Oliveira

    2012-01-01

    Full Text Available This study describes the isolation and structural determination of two amides, isolated for the first time: N,4-dihydroxy-N-(2'-hydroxyethyl-benzamide (0.019% and N,4-dihydroxy-N-(2'-hydroxyethyl-benzeneacetamide (0.023%. These amides, produced by the red macroalgae Bostrychia radicans, had their structures assigned by NMR spectral data and MS analyses. In addition, this chemical study led to the isolation of cholesterol, heptadecane, squalene, trans-phytol, neophytadiene, tetradecanoic and hexadecanoic acids, methyl hexadecanoate and methyl 9-octadecenoate, 4-(methoxymethyl-phenol, 4-hydroxybenzaldehyde, methyl 4-hydroxybenzeneacetate, methyl 2-hydroxy-3-(4-hydroxyphenyl-propanoate, hydroquinone, methyl 4-hydroxymandelate, methyl 4-hydroxybenzoate, 4-hydroxybenzeneacetic acid and (4-hydroxyphenyl-oxo-acetaldehyde. This is the first report concerning these compounds in B. radicans, contributing by illustrating the chemical diversity within the Rhodomelaceae family.

  20. Conversion of amides to esters by the nickel-catalysed activation of amide C-N bonds.

    Science.gov (United States)

    Hie, Liana; Fine Nathel, Noah F; Shah, Tejas K; Baker, Emma L; Hong, Xin; Yang, Yun-Fang; Liu, Peng; Houk, K N; Garg, Neil K

    2015-08-06

    Amides are common functional groups that have been studied for more than a century. They are the key building blocks of proteins and are present in a broad range of other natural and synthetic compounds. Amides are known to be poor electrophiles, which is typically attributed to the resonance stability of the amide bond. Although amides can readily be cleaved by enzymes such as proteases, it is difficult to selectively break the carbon-nitrogen bond of an amide using synthetic chemistry. Here we demonstrate that amide carbon-nitrogen bonds can be activated and cleaved using nickel catalysts. We use this methodology to convert amides to esters, which is a challenging and underdeveloped transformation. The reaction methodology proceeds under exceptionally mild reaction conditions, and avoids the use of a large excess of an alcohol nucleophile. Density functional theory calculations provide insight into the thermodynamics and catalytic cycle of the amide-to-ester transformation. Our results provide a way to harness amide functional groups as synthetic building blocks and are expected to lead to the further use of amides in the construction of carbon-heteroatom or carbon-carbon bonds using non-precious-metal catalysis.

  1. Novel Strategies for Upstream and Downstream Processing of Tannin Acyl Hydrolase

    Directory of Open Access Journals (Sweden)

    Luis V. Rodríguez-Durán

    2011-01-01

    Full Text Available Tannin acyl hydrolase also referred as tannase is an enzyme with important applications in several science and technology fields. Due to its hydrolytic and synthetic properties, tannase could be used to reduce the negative effects of tannins in beverages, food, feed, and tannery effluents, for the production of gallic acid from tannin-rich materials, the elucidation of tannin structure, and the synthesis of gallic acid esters in nonaqueous media. However, industrial applications of tannase are still very limited due to its high production cost. Thus, there is a growing interest in the production, recovery, and purification of this enzyme. Recently, there have been published a number of papers on the improvement of upstream and downstream processing of the enzyme. These papers dealt with the search for new tannase producing microorganisms, the application of novel fermentation systems, optimization of culture conditions, the production of the enzyme by recombinant microorganism, and the design of efficient protocols for tannase recovery and purification. The present work reviews the state of the art of basic and biotechnological aspects of tannin acyl hydrolase, focusing on the recent advances in the upstream and downstream processing of the enzyme.

  2. Prunasin hydrolases during fruit development in sweet and bitter almonds.

    Science.gov (United States)

    Sánchez-Pérez, Raquel; Belmonte, Fara Sáez; Borch, Jonas; Dicenta, Federico; Møller, Birger Lindberg; Jørgensen, Kirsten

    2012-04-01

    Amygdalin is a cyanogenic diglucoside and constitutes the bitter component in bitter almond (Prunus dulcis). Amygdalin concentration increases in the course of fruit formation. The monoglucoside prunasin is the precursor of amygdalin. Prunasin may be degraded to hydrogen cyanide, glucose, and benzaldehyde by the action of the β-glucosidase prunasin hydrolase (PH) and mandelonitirile lyase or be glucosylated to form amygdalin. The tissue and cellular localization of PHs was determined during fruit development in two sweet and two bitter almond cultivars using a specific antibody toward PHs. Confocal studies on sections of tegument, nucellus, endosperm, and embryo showed that the localization of the PH proteins is dependent on the stage of fruit development, shifting between apoplast and symplast in opposite patterns in sweet and bitter cultivars. Two different PH genes, Ph691 and Ph692, have been identified in a sweet and a bitter almond cultivar. Both cDNAs are 86% identical on the nucleotide level, and their encoded proteins are 79% identical to each other. In addition, Ph691 and Ph692 display 92% and 86% nucleotide identity to Ph1 from black cherry (Prunus serotina). Both proteins were predicted to contain an amino-terminal signal peptide, with the size of 26 amino acid residues for PH691 and 22 residues for PH692. The PH activity and the localization of the respective proteins in vivo differ between cultivars. This implies that there might be different concentrations of prunasin available in the seed for amygdalin synthesis and that these differences may determine whether the mature almond develops into bitter or sweet.

  3. Copper ions inactivate S-ade-nosylhomocysteine hydrolase

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    S-adenosylhomocysteine (AdoHcy) hydrolase isan enzyme that regulates biomethylation and some otherphysiological processes. Recombinant AdoHcy hydrolase wasoverexpressed in E. coli JM109 and purified with ion ex-change and gel filtration chromatographies. The effects ofcopper ions (Cu2+) on the activity of AdoHcy hydrolase wereinvestigated and the results showed that Cu2+ inhibited theenzyme's activity by a concentration and time-dependentprocess. The inhibition constant (Ki) and the apparent rateconstant (kapp) were calculated to be (14 + 4) nmol @ L-1 and(1.08 + 0.15) min-1, respectively. The existence of the naturalsubstrate Ado could to some extent prevent Cu2+ from inac-tivating the enzyme, suggesting that copper ions possiblycould compete with the natural substrate on enzyme's sub-strate binding site. Further studies on the mechanism of in-hibition are being carried out.

  4. Optimization of the fermentation conditions and substrate specifity of mycelium-bound ester hydrolases of Aspergillus oryzae Cs007

    Directory of Open Access Journals (Sweden)

    de Hong Yan

    2015-01-01

    Full Text Available In order to improve mycelium-bound ester hydrolases activities of Aspergillus oryzae Cs007, the main production conditions were investigated. The ester hydrolases activities were simultaneously determined by titration assay and spectrophotometric assay methods, using olive oil and p-nitrophenyl esters as substrates, respectively. The optimum carbon source and nitrogen source were olive oil and peptone, with the concentrations of 1% and 2.2%, respectively. The effects of carbon source, nitrogen source and their concentrations on the production of enzymes were identical when the enzymes activities were assayed by the two methods. The mycelium-bound enzymes showed hydrolytic activity toward all the tested p-nitrophenyl esters, triglycerides and fatty acid ethyl esters. But it showed greater preference for long-chain triglycerides and short-chain p-nitrophenyl esters.

  5. Role of an amide bond for self-assembly of surfactants.

    Science.gov (United States)

    Bordes, Romain; Tropsch, Juergen; Holmberg, Krister

    2010-03-01

    Self-assembly in solution and adsorption at the air-water interface and at solid surfaces were investigated for two amino-acid-based surfactants with conductimetry, NMR, tensiometry, quartz crystal microbalance with monitoring of the dissipation (QCM-D), and surface plasmon resonance (SPR). The surfactants studied were sodium N-lauroylglycinate and sodium N-lauroylsarcosinate, differing only in a methyl group on the amide nitrogen for the sarcosinate. Thus, the glycinate but not the sarcosinate surfactant is capable of forming intermolecular hydrogen bonds via the amide group. It was found that the amide bond, N-methylated or not, gave a substantial contribution to the hydrophilicity of the amphiphile. The ability to form intermolecular hydrogen bonds led to tighter packing at the air-water interface and at a hydrophobic surface. It also increased the tendency for precipitation as an acid-soap pair on addition of acid. Adsorption of the surfactants at a gold surface was also investigated and gave unexpected results. The sarcosine-based surfactant seemed to give bilayer adsorption, while the glycine derivative adsorbed as a monolayer.

  6. Dysregulation of soluble epoxide hydrolase and lipidomic profiles in anorexia nervosa.

    Science.gov (United States)

    Shih, P B; Yang, J; Morisseau, C; German, J B; Zeeland, A A Scott-Van; Armando, A M; Quehenberger, O; Bergen, A W; Magistretti, P; Berrettini, W; Halmi, K A; Schork, N; Hammock, B D; Kaye, W

    2016-04-01

    Individuals with anorexia nervosa (AN) restrict eating and become emaciated. They tend to have an aversion to foods rich in fat. Because epoxide hydrolase 2 (EPHX2) was identified as a novel AN susceptibility gene, and because its protein product, soluble epoxide hydrolase (sEH), converts bioactive epoxides of polyunsaturated fatty acid (PUFA) to the corresponding diols, lipidomic and metabolomic targets of EPHX2 were assessed to evaluate the biological functions of EPHX2 and their role in AN. Epoxide substrates of sEH and associated oxylipins were measured in ill AN, recovered AN and gender- and race-matched controls. PUFA and oxylipin markers were tested as potential biomarkers for AN. Oxylipin ratios were calculated as proxy markers of in vivo sEH activity. Several free- and total PUFAs were associated with AN diagnosis and with AN recovery. AN displayed elevated n-3 PUFAs and may differ from controls in PUFA elongation and desaturation processes. Cytochrome P450 pathway oxylipins from arachidonic acid, linoleic acid, alpha-linolenic acid and docosahexaenoic acid PUFAs are associated with AN diagnosis. The diol:epoxide ratios suggest the sEH activity is higher in AN compared with controls. Multivariate analysis illustrates normalization of lipidomic profiles in recovered ANs. EPHX2 influences AN risk through in vivo interaction with dietary PUFAs. PUFA composition and concentrations as well as sEH activity may contribute to the pathogenesis and prognosis of AN. Our data support the involvement of EPHX2-associated lipidomic and oxylipin dysregulations in AN, and reveal their potential as biomarkers to assess responsiveness to future intervention or treatment.

  7. Dysregulation of soluble epoxide hydrolase and lipidomic profiles in anorexia nervosa

    KAUST Repository

    Shih, P. B.

    2015-03-31

    Individuals with anorexia nervosa (AN) restrict eating and become emaciated. They tend to have an aversion to foods rich in fat. Because epoxide hydrolase 2 (EPHX2) was identified as a novel AN susceptibility gene, and because its protein product, soluble epoxide hydrolase (sEH), converts bioactive epoxides of polyunsaturated fatty acid (PUFA) to the corresponding diols, lipidomic and metabolomic targets of EPHX2 were assessed to evaluate the biological functions of EPHX2 and their role in AN. Epoxide substrates of sEH and associated oxylipins were measured in ill AN, recovered AN and gender- and race-matched controls. PUFA and oxylipin markers were tested as potential biomarkers for AN. Oxylipin ratios were calculated as proxy markers of in vivo sEH activity. Several free- and total PUFAs were associated with AN diagnosis and with AN recovery. AN displayed elevated n-3 PUFAs and may differ from controls in PUFA elongation and desaturation processes. Cytochrome P450 pathway oxylipins from arachidonic acid, linoleic acid, alpha-linolenic acid and docosahexaenoic acid PUFAs are associated with AN diagnosis. The diol:epoxide ratios suggest the sEH activity is higher in AN compared with controls. Multivariate analysis illustrates normalization of lipidomic profiles in recovered ANs. EPHX2 influences AN risk through in vivo interaction with dietary PUFAs. PUFA composition and concentrations as well as sEH activity may contribute to the pathogenesis and prognosis of AN. Our data support the involvement of EPHX2-associated lipidomic and oxylipin dysregulations in AN, and reveal their potential as biomarkers to assess responsiveness to future intervention or treatment.

  8. A Substrate-Assisted Mechanism of Nucleophile Activation in a Ser-His-Asp Containing C-C Bond Hydrolase

    Energy Technology Data Exchange (ETDEWEB)

    Ruzzini, Antonio C.; Bhowmik, Shiva; Ghosh, Subhangi; Yam, Katherine C.; Bolin, Jeffrey T.; Eltis, Lindsay D. [Purdue; (UBC)

    2013-11-12

    The meta-cleavage product (MCP) hydrolases utilize a Ser–His–Asp triad to hydrolyze a carbon–carbon bond. Hydrolysis of the MCP substrate has been proposed to proceed via an enol-to-keto tautomerization followed by a nucleophilic mechanism of catalysis. Ketonization involves an intermediate, ESred, which possesses a remarkable bathochromically shifted absorption spectrum. We investigated the catalytic mechanism of the MCP hydrolases using DxnB2 from Sphingomonas wittichii RW1. Pre-steady-state kinetic and LC ESI/MS evaluation of the DxnB2-mediated hydrolysis of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid to 2-hydroxy-2,4-pentadienoic acid and benzoate support a nucleophilic mechanism catalysis. In DxnB2, the rate of ESred decay and product formation showed a solvent kinetic isotope effect of 2.5, indicating that a proton transfer reaction, assigned here to substrate ketonization, limits the rate of acylation. For a series of substituted MCPs, this rate was linearly dependent on MCP pKa2nuc ~ 1). Structural characterization of DxnB2 S105A:MCP complexes revealed that the catalytic histidine is displaced upon substrate-binding. The results provide evidence for enzyme-catalyzed ketonization in which the catalytic His–Asp pair does not play an essential role. The data further suggest that ESred represents a dianionic intermediate that acts as a general base to activate the serine nucleophile. This substrate-assisted mechanism of nucleophilic catalysis distinguishes MCP hydrolases from other serine hydrolases.

  9. An insight into the photophysical properties of amide hydrogen bonded N-(benzo[d]thiazol-2-yl) acetamide crystals

    Science.gov (United States)

    Balijapalli, Umamahesh; Udayadasan, Sathiskumar; Panyam Muralidharan, Vivek; Sukumarapillai, Dileep Kumar; Shanmugam, Easwaramoorthi; Paduthapillai Gopal, Aravindan; S. Rathore, Ravindranath; Kulathu Iyer, Sathiyanarayanan

    2017-02-01

    Three distinct, hydrogen bond associated N-(benzo[d]thiazol-2-yl) acetamides were synthesized by refluxing benzothiazoles with acetic acid. The nature of the assemblies was characteristic to the substituent in the benzothiazole moiety. In N-(benzo[d]thiazol-2-yl)acetamide, water acts as a bridge for forming three hydrogen bonds, as an acceptor to amide Nsbnd H, and donors to carbonyl of amide and thiazole nitrogen assembles of three different N-(benzo[d]thiazol-2-yl)acetamide molecules. The N-(6-methylbenzo[d]thiazol-2-yl)acetamide formed a (amide) N-H…N (thiazole) bonded R22(8) molecular dimers by two homo-intermolecular hydrogen bonding interactions. N-(6-methoxybenzo[d]thiazol-2-yl)acetamide formed (amide)N-H…O (acid) & (acid)O-H…N (thiazole) interactions with the acetic acid, forming a R22(8) hydrogen-bonded ring by two hetero-intermolecular hydrogen bonding interactions.

  10. Immobilization of lysozyme-cellulose amide-linked conjugates on cellulose i and ii cotton nanocrystalline preparations

    Science.gov (United States)

    Lysozyme was attached through an amide linkage between some of the protein’s aspartate and glutamate residues to amino-glycine-cellulose (AGC), which was prepared by esterification of glycine to preparations of cotton nanocrystals (CNC). The nanocrystalline preparations were produced through acid h...

  11. AMID: autonomous modeler of intragenic duplication.

    Science.gov (United States)

    Kummerfeld, Sarah K; Weiss, Anthony S; Fekete, Alan; Jermiin, Lars S

    2003-01-01

    Intragenic duplication is an evolutionary process where segments of a gene become duplicated. While there has been much research into whole-gene or domain duplication, there have been very few studies of non-tandem intragenic duplication. The identification of intragenically replicated sequences may provide insight into the evolution of proteins, helping to link sequence data with structure and function. This paper describes a tool for autonomously modelling intragenic duplication. AMID provides: identification of modularly repetitive genes; an algorithm for identifying repeated modules; and a scoring system for evaluating the modules' similarity. An evaluation of the algorithms and use cases are presented.

  12. Amide as an efficient ligand in the palladium-catalyzed Suzuki coupling reaction in water/ethanol under aerobic conditions

    Institute of Scientific and Technical Information of China (English)

    Hai Yang Liu; Kun Wang; Hai Yan Fu; Mao Lin Yuan; Hua Chen; Rui Xiang Li

    2011-01-01

    Amide, which is derived from proline and is inexpensive and air-stable, has been synthesized and characterized by 1H NMR,13C NMR, and MS. It was found to be an efficient ligand in the palladium-catalyzed Suzuki cross-coupling reaction. In the Pd/amide catalytic system, aryl bromides can be coupled with phenylboronic acid in ethanol/water (1:2;v/v) in excellent yields even with a low Pd loading of 0.01 mol%. Moreover, the scope of the reaction is broad, and a wide variety of functional groups are tolerant.

  13. Epoxyeicosatrienoic acids and glucose homeostasis in mice and men.

    Science.gov (United States)

    Luther, James M; Brown, Nancy J

    2016-09-01

    Epoxyeicosatrienoic acids (EETs) are formed from arachidonic acid by the action of P450 epoxygenases (CYP2C and CYP2J). Effects of EETs are limited by hydrolysis by soluble epoxide hydrolase to less active dihydroxyeicosatrienoic acids. Studies in rodent models provide compelling evidence that epoxyeicosatrienoic acids exert favorable effects on glucose homeostasis, either by enhancing pancreatic islet cell function or by increasing insulin sensitivity in peripheral tissues. Specifically, the tissue expression of soluble epoxide hydrolase appears to be increased in rodent models of obesity and diabetes. Pharmacological inhibition of epoxide hydrolase or deletion of the gene encoding soluble epoxide hydrolase (Ephx2) preserves islet cells in rodent models of type 1 diabetes and enhances insulin sensitivity in models of type 2 diabetes, as does administration of epoxyeicosatrienoic acids or their stable analogues. In humans, circulating concentrations of epoxyeicosatrienoic acids correlate with insulin sensitivity, and a loss-of-function genetic polymorphism in EPHX2 is associated with insulin sensitivity.

  14. Omega-3 N-acylethanolamines are endogenously synthesised from omega-3 fatty acids in different human prostate and breast cancer cell lines.

    Science.gov (United States)

    Brown, I; Wahle, K W J; Cascio, M G; Smoum-Jaouni, R; Mechoulam, R; Pertwee, R G; Heys, S D

    2011-12-01

    Omega-3 (n-3) fatty acids inhibit breast and prostate cancer cell growth. We previously showed that N-acylethanolamine derivatives of n-3 (n-3-NAE) are endocannabinoids, which regulate cancer cell proliferation. These n-3-NAE are synthesised in certain cells/tissues, after supplementing with fatty acids, however, no one has assessed whether and to what extent this occurs in cancer cells. We determined levels of endogenous n-3-NAEs in hormone sensitive and insensitive prostate and breast cancer cells and subsequent effects on other endocannabinoids (anandamide and 2-arachidonoylglycerol), before and after supplementing with DHA and EPA fatty acids, using HPLC tandem mass spectrometry. This is the first study reporting that n-3-NAEs are synthesised from their parent n-3 fatty acids in cancer cells, regardless of tumour type, hormone status or the presence of fatty acid amide hydrolase. This could have important implications for the use of n-3 fatty acids as therapeutic agents in breast and prostate cancers expressing cannabinoid receptors.

  15. Further characterization of intestinal lactase/phlorizin hydrolase

    DEFF Research Database (Denmark)

    Skovbjerg, H; Norén, O; Sjöström, H

    1982-01-01

    Pig intestinal lactase/phlorizin hydrolase (EC 3.2.1.23/62) was purified in its amphiphilic form by immunoadsorbent chromatography. The purified enzyme was free of other known brush border enzymes and appeared homogeneous in immunoelectrophoresis and polyacrylamide gel electrophoresis in the pres......Pig intestinal lactase/phlorizin hydrolase (EC 3.2.1.23/62) was purified in its amphiphilic form by immunoadsorbent chromatography. The purified enzyme was free of other known brush border enzymes and appeared homogeneous in immunoelectrophoresis and polyacrylamide gel electrophoresis...... in the presence of SDS. Pig lactase/phlorizin hydrolase was shown to have the same quaternary structure as the human enzyme, i.e., built up of two polypeptides of the same molecular weight (160000). In addition to hydrolyzing lactose, phlorizin and a number of synthetic substrates, both the human and the pig...... enzyme were shown to have a considerable activity against cellotriose and cellotetraose, and a low but significant activity against cellulose. The lactase/phlorizin hydrolase isolated from pigs in which the pancreatic ducts had been disconnected 3 days before death and from Ca2+-precipitated enterocyte...

  16. Properties of epoxide hydrolase from the yeast Rhodotorula glutinis

    NARCIS (Netherlands)

    Ariës-Kronenburg, N.A.E.

    2002-01-01

     Epoxide hydrolases are ubiquitous enzymes that can be found in nearly all living organisms. Some of the enzymes play an important role in detoxifying xenobiotic and metabolic compounds. Others are important in the growth of organisms like the juvenile hormone in some insec

  17. Bile salt hydrolase of Bifidobacterium longum - Biochemical and genetic characterization

    NARCIS (Netherlands)

    Tanaka, H; Hashiba, Honoo; Kok, Jan; Mierau, Igor

    2000-01-01

    A bile salt hydrolase (BSH) was isolated from Bifidobacterium longum SBT2928, purified, and characterized, Furthermore, we describe for the first time cloning and analysis of the gene encoding BSII (bsh) in a member of the genus Bifidobacterium. The enzyme has a native molecular weight of 125,000 to

  18. SYNTHESIS AND CHARACTERIZATION OF THERMOTROPIC COPOLYESTERS AND COPOLY (ESTER-AMIDE)S CONTAINING OXYETHYLENE-ETHER AS THE SPACER

    Institute of Scientific and Technical Information of China (English)

    WANG Shanger; MO Zhishen; ZHANG Hongfang; FENG Zhiliu

    1995-01-01

    Flexible oxyethylene-ether was introduced into the aromatic copolyesters and copoly (ester-amide)s to reduce the melting point of resulting polymers. The melting point was greatly reduced to 200℃ or even lower in some cases, and the molecular weight was satisfactorily high as reflected by inherent viscosity. The polymers exhibited high thermal stability and good mechanical properties as determined by TGA and mechanical tests. The copolyester showed better crystallinity and liquid crystallinity than corresponding copoly(ester-amide)s with similar monomer composition as reflected by POM observation and WAXD study. The melting points for both copolyesters and copoly (ester-amide)s showed great dependence on the pacetoxybenzoic acid (PAB) content in monomer composition and reached the lowest value when PAB was 29 mol%.

  19. Probing the role of backbone hydrogen bonds in protein-peptide interactions by amide-to-ester mutations

    DEFF Research Database (Denmark)

    Eildal, Jonas N N; Hultqvist, Greta; Balle, Thomas;

    2013-01-01

    -protein interactions, those of the PDZ domain family involve formation of intermolecular hydrogen bonds: C-termini or internal linear motifs of proteins bind as β-strands to form an extended antiparallel β-sheet with the PDZ domain. Whereas extensive work has focused on the importance of the amino acid side chains...... of the protein ligand, the role of the backbone hydrogen bonds in the binding reaction is not known. Using amide-to-ester substitutions to perturb the backbone hydrogen-bonding pattern, we have systematically probed putative backbone hydrogen bonds between four different PDZ domains and peptides corresponding...... to natural protein ligands. Amide-to-ester mutations of the three C-terminal amides of the peptide ligand severely affected the affinity with the PDZ domain, demonstrating that hydrogen bonds contribute significantly to ligand binding (apparent changes in binding energy, ΔΔG = 1.3 to >3.8 kcal mol(-1...

  20. Proximate and qualitative analysis of different parts of Piper sarmentosum, and quantification of total amides in various extracts

    Directory of Open Access Journals (Sweden)

    K Hussain

    2009-01-01

    Full Text Available Present study aimed to analyze crude powders and extracts of different parts of Piper sarmentosum for proximate, qualitative and quantitative studies to prepare standardized botanical drugs from the plant. Unlike synthetic drugs, standardization of botanical drugs is always challenging for natural product researchers due to inadequacy and unavailability of standards and methods. Standardization of botanical drugs is not just an analytical process which ends with the detection of few constituents rather it embodies a set of analytical, biochemical and biological protocols. Keeping analytical protocols in view, crude powders were analyzed for the content of moisture, total ash, acid insoluble ash, sulphated ash and soluble extractives in water and methanol. These physicochemical properties were found within specified limits. Comparison of Fourier Transform Infrared (FTIR fingerprints of crude powders of different parts indicated the difference of constituents. Similarly, comparison of ultra violet (UV profiles of extracts of all the parts exhibited discrimination. Qualitative analysis of aqueous and ethanol extracts by high performance thin layer chromatography (HPTLC indicated the presence of amides in ethanol extracts of all parts of the plant. Quantitative analysis of extracts indicated that total amide content was significantly higher by colorimetry as compared to UV spectrophotometry. The distribution of amides in different parts was in the order fruit > root > leaf > stem (P=0.000. It is concluded from the study that amide content varies in different parts of the plant and ethanol is a better solvent for their extraction. Additionally, colorimetric method exhibits high content of amides.

  1. Insights into Substrate Specificity of NlpC/P60 Cell Wall Hydrolases Containing Bacterial SH3 Domains

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Qingping; Mengin-Lecreulx, Dominique; Liu, Xueqian W.; Patin, Delphine; Farr, Carol L.; Grant, Joanna C.; Chiu, Hsiu-Ju; Jaroszewski, Lukasz; Knuth, Mark W.; Godzik, Adam; Lesley, Scott A.; Elsliger, Marc-André; Deacon, Ashley M.; Wilson, Ian A.

    2015-09-15

    ABSTRACT

    Bacterial SH3 (SH3b) domains are commonly fused with papain-like Nlp/P60 cell wall hydrolase domains. To understand how the modular architecture of SH3b and NlpC/P60 affects the activity of the catalytic domain, three putative NlpC/P60 cell wall hydrolases were biochemically and structurally characterized. These enzymes all have γ-d-Glu-A2pm (A2pm is diaminopimelic acid) cysteine amidase (ordl-endopeptidase) activities but with different substrate specificities. One enzyme is a cell wall lysin that cleaves peptidoglycan (PG), while the other two are cell wall recycling enzymes that only cleave stem peptides with an N-terminall-Ala. Their crystal structures revealed a highly conserved structure consisting of two SH3b domains and a C-terminal NlpC/P60 catalytic domain, despite very low sequence identity. Interestingly, loops from the first SH3b domain dock into the ends of the active site groove of the catalytic domain, remodel the substrate binding site, and modulate substrate specificity. Two amino acid differences at the domain interface alter the substrate binding specificity in favor of stem peptides in recycling enzymes, whereas the SH3b domain may extend the peptidoglycan binding surface in the cell wall lysins. Remarkably, the cell wall lysin can be converted into a recycling enzyme with a single mutation.

    IMPORTANCEPeptidoglycan is a meshlike polymer that envelops the bacterial plasma membrane and bestows structural integrity. Cell wall lysins and recycling enzymes are part of a set of lytic enzymes that target covalent bonds connecting the amino acid and amino sugar building blocks of the PG network. These hydrolases are involved in processes such as cell growth and division, autolysis, invasion, and PG turnover and recycling. To avoid cleavage of unintended substrates, these enzymes have very selective substrate specificities. Our biochemical and structural

  2. Exploration of the chlorpyrifos escape pathway from acylpeptide hydrolases using steered molecular dynamics simulations.

    Science.gov (United States)

    Wang, Dongmei; Jin, Hanyong; Wang, Junling; Guan, Shanshan; Zhang, Zuoming; Han, Weiwei

    2016-01-01

    Acylpeptide hydrolases (APH) catalyze the removal of an N-acylated amino acid from blocked peptides. APH is significantly more sensitive than acetylcholinesterase, a target of Alzheimer's disease, to inhibition by organophosphorus (OP) compounds. Thus, OP compounds can be used as a tool to probe the physiological functions of APH. Here, we report the results of a computational study of molecular dynamics simulations of APH bound to the OP compounds and an exploration of the chlorpyrifos escape pathway using steered molecular dynamics (SMD) simulations. In addition, we apply SMD simulations to identify potential escape routes of chlorpyrifos from hydrolase hydrophobic cavities in the APH-inhibitor complex. Two previously proposed APH pathways were reliably identified by CAVER 3.0, with the estimated relative importance of P1 > P2 for its size. We identify the major pathway, P2, using SMD simulations, and Arg526, Glu88, Gly86, and Asn65 are identified as important residues for the ligand leaving via P2. These results may help in the design of APH-targeting drugs with improved efficacy, as well as in understanding APH selectivity of the inhibitor binding in the prolyl oligopeptidase family.

  3. Beta-glucuronidase of family-2 glycosyl hydrolase: a missing member in plants.

    Science.gov (United States)

    Arul, Loganathan; Benita, George; Sudhakar, Duraialagaraja; Thayumanavan, Balsamy; Balasubramanian, Ponnusamy

    2008-01-01

    Glycosyl hydrolases hydrolyze the glycosidic bond in carbohydrates or between a carbohydrate and a non-carbohydrate moiety. beta-glucuronidase (GUS) is classified under two glycosyl hydrolase families (2 and 79) and the family-2 beta-glucuronidase is reported in a wide range of organisms, but not in plants. The family-79 endo-beta-glucuronidase (heparanase) is reported in microorganisms, vertebrates and plants. The E. coli family-2 beta-glucuronidase (uidA) had been successfully devised as a reporter gene in plant transformation on the basis that plants do not have homologous GUS activity. On the contrary, histochemical staining with X-Gluc was reported in wild type (non-transgenic) plants. Data shows that, family-2 beta-glucuronidase homologous sequence is not found in plants. Further, beta-glucuronidases of family-2 and 79 lack appreciable sequence similarity. However, the catalytic site residues, glutamic acid and tyrosine of the family-2 beta-glucuronidase are found to be conserved in family-79 beta-glucuronidase of plants. This led to propose that the GUS staining reported in wild type plants is largely because of the broad substrate specificity of family-79 beta-glucuronidase on X-Gluc and not due to the family-2 beta-glucuronidase, as the latter has been found to be missing in plants.

  4. Structural and kinetic insights into the mechanism of 5-hydroxyisourate hydrolase from Klebsiella pneumoniae

    Energy Technology Data Exchange (ETDEWEB)

    French, Jarrod B.; Ealick, Steven E., E-mail: see3@cornell.edu [Cornell University, Ithaca, NY 14853-1301 (United States)

    2011-08-01

    The crystal structure of 5-hydroxyisourate hydrolase from K. pneumoniae and the steady-state kinetic parameters of the native enzyme as well as several mutants provide insights into the catalytic mechanism of this enzyme and the possible roles of the active-site residues. The stereospecific oxidative degradation of uric acid to (S)-allantoin has recently been demonstrated to proceed via two unstable intermediates and requires three separate enzymatic reactions. The second step of this reaction, the conversion of 5-hydroxyisourate (HIU) to 2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline, is catalyzed by HIU hydrolase (HIUH). The high-resolution crystal structure of HIUH from the opportunistic pathogen Klebsiella pneumoniae (KpHIUH) has been determined. KpHIUH is a homotetrameric protein that, based on sequence and structural similarity, belongs to the transthyretin-related protein family. In addition, the steady-state kinetic parameters for this enzyme and four active-site mutants have been measured. These data provide valuable insight into the functional roles of the active-site residues. Based upon the structural and kinetic data, a mechanism is proposed for the KpHIUH-catalyzed reaction.

  5. Glycosyl hydrolases of cell wall are induced by sugar starvation in Arabidopsis.

    Science.gov (United States)

    Lee, Eun-Jeong; Matsumura, Yasuhiro; Soga, Kouichi; Hoson, Takayuki; Koizumi, Nozomu

    2007-03-01

    Three Arabidopsis genes encoding a putative beta-galactosidase (At5g56870), beta-xylosidase (At5g49360) and beta-glucosidase (At3g60140) are induced by sugar starvation. The deduced proteins belong to the glycosyl hydrolase families 35, 3 and 1, respectively. They are predicted to be secretory proteins that play roles in modification of cell wall polysaccharides based on amino acid similarity. The beta-galactosidase encoded by At5g56870 was identified as a secretory protein in culture medium of suspension cells by mass spectrometry analysis. This protein was specifically detected under sugar-starved conditions with a specific antibody. Induction of these genes was repressed in suspension cells grown with galactose, xylose and glucose, as well as with sucrose. In planta, expression of the genes and protein accumulation were detected when photosynthesis was inhibited. Glycosyl hydrolase activity against galactan also increased during sugar starvation. The amount of monosaccharide in pectin and hemicellulose in detached leaves decreased in response to sugar starvation. These findings suggest that the cell wall may function as a storage reserve of carbon in addition to providing physical support for the plant body.

  6. Synthesis and characterisation of uniform bisester tetra-amide segments

    NARCIS (Netherlands)

    Krijgsman, J.; Husken, D.; Gaymans, R.J.

    2003-01-01

    The synthesis and characterisation of a new type of high melting and fast crystallising amide units that can be used for copolymerisation have been studied. These bisester tetra-amide or TxTxT-dimethyl segments (T is a terephthalic unit and x=(CH2)n (n=2–8)) can be synthesised in a two-step reaction

  7. Synthesis of Novel Extractants——Amide Podands

    Institute of Scientific and Technical Information of China (English)

    TANGHong-bin; ZHUWen-bin; YEGuo-an; ZHUZhi-xuan; CHENWen-jun

    2003-01-01

    Amide podands which are used as a novel extractants are widely concerned recently. In the early stage, the studies were focused on the amide potands substituted with short-chain alky group, and for avoiding the formation of the second organic phase, aromatic, halogenated or higher alcohol compound must be used as diluents.

  8. Picosecond thermometer in the amide I band of myoglobin

    DEFF Research Database (Denmark)

    Austin, R.H.; Xie, A.; Meer, L. van der;

    2005-01-01

    The amide I and II bands in myoglobin show a heterogeneous temperature dependence, with bands at 6.17 and 6.43 mu m which are more intense at low temperatures. The amide I band temperature dependence is on the long wavelength edge of the band, while the short wavelength side has almost no tempera...

  9. Novel glycoside hydrolases from thermophilic fungi

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to isolated polypeptides having cellulolytic activity or hemicellulolytic activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of produ...

  10. Preparation and characterization of amidated pectin based hydrogels for drug delivery system.

    Science.gov (United States)

    Mishra, R K; Datt, M; Pal, K; Banthia, A K

    2008-06-01

    In the current studies attempts were made to prepare hydrogels by chemical modification of pectin with ethanolamine (EA) in different proportions. Chemically modified pectin products were crosslinked with glutaraldehyde reagent for preparing hydrogels. The hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), organic elemental analysis, X-ray diffraction studies (XRD), swelling studies, biocompatibility and hemocompatibility studies. Mechanical properties of the prepared hydrogels were evaluated by tensile test. The hydrogels were loaded with salicylic acid (used as a model drug) and drug release studies were done in a modified Franz's diffusion cell. FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands. XRD studies indicated increase in crystallinity in the hydrogels as compared to unmodified pectin. The degree of amidation (DA) and molar and mass reaction yields (YM and YN) was calculated based on the results of organic elemental analysis. The hydrogels showed good water holding properties and were found to be compatible with B-16 melanoma cells & human blood.

  11. Temperature-Dependence of the Amide-I Frequency Map for Peptides and Proteins

    Institute of Scientific and Technical Information of China (English)

    Chen Han; Jian-ping Wang

    2011-01-01

    In our recent work [Phys.Chem.Chem.Phys.11,9149 (2009)],a molecular-mechanics force field-based amide-I vibration frequency map (MM-map) for peptides and proteins was constructed.In this work,the temperature dependence of the MM-map is examined based on high-temperature molecular dynamics simulations and infrared (IR) experiments.It is shown that the 298-K map works for up to 500-K molecular dynamics trajectories,which reasonably reproduces the 88 ℃ experimental IR results.Linear IR spectra are also simulated for two tripeptides containing natural and unnatural amino acid residues,and the results are in reasonable agreement with experiment.The results suggest the MM-map can be used to obtain the temperature-dependent amide-I local mode frequencies and their distributions for peptide oligomers,which is useful in particular for understanding the IR signatures of the thermally unfolded species.

  12. Microwave assisted synthesis and solid-state characterization of lithocholyl amides of isomeric aminopyridines.

    Science.gov (United States)

    Ahonen, Kari V; Lahtinen, Manu K; Valkonen, Arto M; Dracínský, Martin; Kolehmainen, Erkki T

    2011-02-01

    Microwave (MW) assisted synthesis and solid state structural characterizations of novel lithocholyl amides of 2-, 3-, and 4-aminopyridine are reported. It is shown that the MW technique is a proper method in the preparation of N-lithocholyl amides of isomeric aminopyridines. It offers many advantages compared to conventional heating. The molecular and crystal structures as well as the polymorphic and hydrated forms of prepared conjugates with their thermodynamic stabilities have been characterized by means of high resolution liquid- and solid-state NMR spectroscopy, single crystal and powder X-ray diffraction, and thermogravimetric analysis. Owing to the many biological functions of bile acids and amino substituted nitrogen heterocycles, knowledge of the crystal packing of these novel conjugates may have relevance for potential pharmaceutical applications.

  13. Understanding the Amide-II Vibrations in β-Peptides.

    Science.gov (United States)

    Zhao, Juan; Wang, Jianping

    2015-11-25

    In this work, the vibrational characteristics of the amide-II modes in β-peptides in five helical conformations, namely, 8-, 10-, 12-, 14-, and 10/12-helices, have been examined. Remarkable conformational dependence of the amide-II spectral profile is obtained by ab initio computations as well as modeling analysis. Intramolecular hydrogen-bonding interaction and its influence on backbone structure and on the amide-II local-mode transition frequencies and intensities are examined. Through-space and through-bond contributions of the amide-II vibrational couplings are analyzed, and it was found that hydrogen-bonding interaction is not a determining factor for the coupling strength. The results reported here provide useful benchmarks for understanding experimental amide-II infrared spectra of β-peptides and suggest the potential application of this mode on monitoring the structures and dynamics of β-peptides.

  14. Vaccenic acid suppresses intestinal inflammation by increasing anandamide and related N-acylethanolamines in the JCR:LA-cp rat.

    Science.gov (United States)

    Jacome-Sosa, Miriam; Vacca, Claudia; Mangat, Rabban; Diane, Abdoulaye; Nelson, Randy C; Reaney, Martin J; Shen, Jianheng; Curtis, Jonathan M; Vine, Donna F; Field, Catherine J; Igarashi, Miki; Piomelli, Daniele; Banni, Sebastiano; Proctor, Spencer D

    2016-04-01

    Vaccenic acid (VA), the predominant ruminant-derivedtransfat in the food chain, ameliorates hyperlipidemia, yet mechanisms remain elusive. We investigated whether VA could influence tissue endocannabinoids (ECs) by altering the availability of their biosynthetic precursor, arachidonic acid (AA), in membrane phospholipids (PLs). JCR:LA-cprats were assigned to a control diet with or without VA (1% w/w),cis-9,trans-11 conjugated linoleic acid (CLA) (1% w/w) or VA+CLA (1% + 0.5% w/w) for 8 weeks. VA reduced the EC, 2-arachidonoylglycerol (2-AG), in the liver and visceral adipose tissue (VAT) relative to control diet (P 0.05). Interestingly, VA increased jejunal concentrations of anandamide and those of the noncannabinoid signaling molecules, oleoylethanolamide and palmitoylethanolamide, relative to control diet (P< 0.05). This was consistent with a lower jejunal protein abundance (but not activity) of their degrading enzyme, fatty acid amide hydrolase, as well as the mRNA expression of TNFα and interleukin 1β (P< 0.05). The ability of VA to reduce 2-AG in the liver and VAT provides a potential mechanistic explanation to alleviate ectopic lipid accumulation. The opposing regulation of ECs and other noncannabinoid lipid signaling molecules by VA suggests an activation of benefit via the EC system in the intestine.

  15. The biosynthesis of N-arachidonoyl dopamine (NADA), a putative endocannabinoid and endovanilloid, via conjugation of arachidonic acid with dopamine.

    Science.gov (United States)

    Hu, Sherry Shu-Jung; Bradshaw, Heather B; Benton, Valery M; Chen, Jay Shih-Chieh; Huang, Susan M; Minassi, Alberto; Bisogno, Tiziana; Masuda, Kim; Tan, Bo; Roskoski, Robert; Cravatt, Benjamin F; Di Marzo, Vincenzo; Walker, J Michael

    2009-10-01

    N-arachidonoyl dopamine (NADA) is an endogenous ligand that activates the cannabinoid type 1 receptor and the transient receptor potential vanilloid type 1 channel. Two potential biosynthetic pathways for NADA have been proposed, though no conclusive evidence exists for either. The first is the direct conjugation of arachidonic acid with dopamine and the other is via metabolism of a putative N-arachidonoyl tyrosine (NA-tyrosine). In the present study we investigated these biosynthetic mechanisms and report that NADA synthesis requires TH in dopaminergic terminals; however, NA-tyrosine, which we identify here as an endogenous lipid, is not an intermediate. We show that NADA biosynthesis primarily occurs through an enzyme-mediated conjugation of arachidonic acid with dopamine. While this conjugation likely involves a complex of enzymes, our data suggest a direct involvement of fatty acid amide hydrolase in NADA biosynthesis either as a rate-limiting enzyme that liberates arachidonic acid from AEA, or as a conjugation enzyme, or both.

  16. Effect of Bile Salt Hydrolase Inhibitors on a Bile Salt Hydrolase from Lactobacillus acidophilus

    Directory of Open Access Journals (Sweden)

    Jun Lin

    2014-12-01

    Full Text Available Bile salt hydrolase (BSH, a widely distributed function of the gut microbiota, has a profound impact on host lipid metabolism and energy harvest. Recent studies suggest that BSH inhibitors are promising alternatives to antibiotic growth promoters (AGP for enhanced animal growth performance and food safety. Using a high-purity BSH from Lactobacillus salivarius strain, we have identified a panel of BSH inhibitors. However, it is still unknown if these inhibitors also effectively inhibit the function of the BSH enzymes from other bacterial species with different sequence and substrate spectrum. In this study, we performed bioinformatics analysis and determined the inhibitory effect of identified BSH inhibitors on a BSH from L. acidophilus. Although the L. acidophilus BSH is phylogenetically distant from the L. salivarius BSH, sequence analysis and structure modeling indicated the two BSH enzymes contain conserved, catalytically important amino residues and domain. His-tagged recombinant BSH from L. acidophilus was further purified and used to determine inhibitory effect of specific compounds. Previously identified BSH inhibitors also exhibited potent inhibitory effects on the L. acidophilus BSH. In conclusion, this study demonstrated that the BSH from L. salivarius is an ideal candidate for screening BSH inhibitors, the promising alternatives to AGP for enhanced feed efficiency, growth performance and profitability of food animals.

  17. Inhibitors of soluble epoxide hydrolase attenuate vascular smooth muscle cell proliferation

    Science.gov (United States)

    Davis, Benjamin B.; Thompson, David A.; Howard, Laura L.; Morisseau, Christophe; Hammock, Bruce D.; Weiss, Robert H.

    2002-02-01

    Atherosclerosis, in its myriad incarnations the foremost killer disease in the industrialized world, is characterized by aberrant proliferation of vascular smooth muscle (VSM) cells in part as a result of the recruitment of inflammatory cells to the blood vessel wall. The epoxyeicosatrienoic acids are synthesized from arachidonic acid in a reaction catalyzed by the cytochrome P450 system and are vasoactive substances. Metabolism of these compounds by epoxide hydrolases results in the formation of compounds that affect the vasculature in a pleiotropic manner. As an outgrowth of our observations that urea inhibitors of the soluble epoxide hydrolase (sEH) reduce blood pressure in spontaneously hypertensive rats as well as the findings of other investigators that these compounds possess antiinflammatory actions, we have examined the effect of sEH inhibitors on VSM cell proliferation. We now show that the sEH inhibitor 1-cyclohexyl-3-dodecyl urea (CDU) inhibits human VSM cell proliferation in a dose-dependent manner and is associated with a decrease in the level of cyclin D1. In addition, cis-epoxyeicosatrienoic acid mimics the growth-suppressive activity of CDU; there is no evidence of cellular toxicity or apoptosis in CDU-treated cells when incubated with 20 μM CDU for up to 48 h. These results, in light of the antiinflammatory and antihypertensive properties of these compounds that have been demonstrated already, suggest that the urea class of sEH inhibitors may be useful for therapy for diseases such as hypertension and atherosclerosis characterized by exuberant VSM cell proliferation and vascular inflammation.

  18. Cytotoxic cassaine diterpenoid-diterpenoid amide dimers and diterpenoid amides from the leaves of Erythrophleum fordii.

    Science.gov (United States)

    Du, Dan; Qu, Jing; Wang, Jia-Ming; Yu, Shi-Shan; Chen, Xiao-Guang; Xu, Song; Ma, Shuang-Gang; Li, Yong; Ding, Guang-Zhi; Fang, Lei

    2010-10-01

    Detailed phytochemical investigation from the leaves of Erythrophleum fordii resulted in the isolation of 13 compounds, including three cassaine diterpenoid-diterpenoid amide dimers (1, 3 and 5), and seven cassaine diterpenoid amides (6 and 8-13), together with three previously reported ones, erythrophlesins D (2), C (4) and 3beta-hydroxynorerythrosuamide (7). Compounds 1, 3 and 5 are further additions to the small group of cassaine diterpenoid dimers represented by erythrophlesins A-D. Their structures were determined by analysis of extensive one- and two-dimensional NMR experiments and ESIMS methods. Cytotoxic activities of the isolated compounds were tested against HCT-8, Bel-7402, BGC-823, A549 and A2780 human cancer cell lines in the MTT test. Results showed that compounds 1 and 3-5 exhibited significantly selective cytotoxic activities (IC(50)<10 microM) against these cells, respectively.

  19. Structural Characterization of N-Alkylated Twisted Amides: Consequences for Amide Bond Resonance and N-C Cleavage.

    Science.gov (United States)

    Hu, Feng; Lalancette, Roger; Szostak, Michal

    2016-04-11

    Herein, we describe the first structural characterization of N-alkylated twisted amides prepared directly by N-alkylation of the corresponding non-planar lactams. This study provides the first experimental evidence that N-alkylation results in a dramatic increase of non-planarity around the amide N-C(O) bond. Moreover, we report a rare example of a molecular wire supported by the same amide C=O-Ag bonds. Reactivity studies demonstrate rapid nucleophilic addition to the N-C(O) moiety of N-alkylated amides, indicating the lack of n(N) to π*(C=O) conjugation. Most crucially, we demonstrate that N-alkylation activates the otherwise unreactive amide bond towards σ N-C cleavage by switchable coordination.

  20. Hepatoprotective amide constituents from the fruit of Piper chaba: Structural requirements, mode of action, and new amides.

    Science.gov (United States)

    Matsuda, Hisashi; Ninomiya, Kiyofumi; Morikawa, Toshio; Yasuda, Daisuke; Yamaguchi, Itadaki; Yoshikawa, Masayuki

    2009-10-15

    The 80% aqueous acetone extract from the fruit of Piper chaba (Piperaceae) was found to have hepatoprotective effects on D-galactosamine (D-GalN)/lipopolysaccharide-induced liver injury in mice. From the ethyl acetate-soluble fraction, three new amides, piperchabamides E, G, and H, 33 amides, and four aromatic constituents were isolated. Among the isolates, several amide constituents inhibited D-GalN/tumor necrosis factor-alpha (TNF-alpha)-induced death of hepatocytes, and the following structural requirements were suggested: (i) the amide moiety is essential for potent activity; and (ii) the 1,9-decadiene structure between the benzene ring and the amide moiety tended to enhance the activity. Moreover, a principal constituent, piperine, exhibited strong in vivo hepatoprotective effects at doses of 5 and 10 mg/kg, po and its mode of action was suggested to depend on the reduced sensitivity of hepatocytes to TNF-alpha.

  1. Benzoylureas as removable cis amide inducers: synthesis of cyclic amides via ring closing metathesis (RCM).

    Science.gov (United States)

    Brady, Ryan M; Khakham, Yelena; Lessene, Guillaume; Baell, Jonathan B

    2011-02-07

    Rapid and high yielding synthesis of medium ring lactams was made possible through the use of a benzoylurea auxiliary that serves to stabilize a cisoid amide conformation, facilitating cyclization. The auxiliary is released after activation under the mild conditions required to deprotect a primary amine, such as acidolysis of a Boc group in the examples given here. This methodology is a promising tool for the synthesis of medium ring lactams, macrocyclic natural products and peptides.

  2. Structural and kinetic insights into the mechanism of 5-hydroxyisourate hydrolase from Klebsiella pneumoniae

    Energy Technology Data Exchange (ETDEWEB)

    French, Jarrod B.; Ealick, Steven E. (Cornell)

    2011-07-19

    The stereospecific oxidative degradation of uric acid to (S)-allantoin has recently been demonstrated to proceed via two unstable intermediates and requires three separate enzymatic reactions. The second step of this reaction, the conversion of 5-hydroxyisourate (HIU) to 2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline, is catalyzed by HIU hydrolase (HIUH). The high-resolution crystal structure of HIUH from the opportunistic pathogen Klebsiella pneumoniae (KpHIUH) has been determined. KpHIUH is a homotetrameric protein that, based on sequence and structural similarity, belongs to the transthyretin-related protein family. In addition, the steady-state kinetic parameters for this enzyme and four active-site mutants have been measured. These data provide valuable insight into the functional roles of the active-site residues. Based upon the structural and kinetic data, a mechanism is proposed for the KpHIUH-catalyzed reaction.

  3. Studies on culture condition and extracellular hydrolase of psychrophilic bacteria from Arctic sea ice

    Institute of Scientific and Technical Information of China (English)

    Li Xiaohui; Yu Yong; Li Huirong; Zhang Lin; Jiang Xinyin; Ren Daming

    2008-01-01

    Arctic sea ice in the polar region provides a cold habitat for microbial community.Arctic sea ice microorganisms are revealed to be of considerable importance in basic research and potential in biotechnological application.This paper investigated the culture condition and extracellular hydrolase of 14 strains of different Arctic sea ice bacteria.The results showed that optimal growth temperature of strains is 15 ℃ or 20 ℃.The optimal pH is about 8.0.They hardly grow at acid condition.3% NaCl is necessary for better growth.These strains have different abilities in producing amylase,protease,cellulase and lipase.Pseudoalteronomas sp.Bsi429 and Pseudoalteronomas sp.Bsi539 produced both cellulose,protease and lipase.These results provide a basis for further developing and exploiting the cold adapted marine enzyme resources.

  4. Structure and property of self-assemble valinyl bolaform amides having different chirality.

    Science.gov (United States)

    Doi, M; Asano, A; Yoshida, H; Inouguchi, M; Iwanaga, K; Sasaki, M; Katsuya, Y; Taniguchi, T; Yamamoto, D

    2005-10-01

    Bolaform amides were designed from N,N'-bis(carboethoxy-L-valinyl)-diaminoethane (1) by linking t-butyloxycarbonyl-valine through ethylenediamine (EDA) to enable spectroscopic and X-ray diffraction analyses. N,N'-Bis(Boc-L-valinyl)-diaminoethane (2) and N,N'-bis(Boc-D-valinyl)-diaminoethane (3) were composed of L-Val and D-Val, respectively. N-(Boc-L-valinyl)-N'-(Boc-D-valinyl)-diaminoethane (4) was composed of both L-Val and D-Val, and was achiral (meso-peptide). Peptide 5 was a 1:1 mixture of 2 and 3, and was also achiral (racemate). These peptides mediated gelation of corn oil at a concentration of approximately 1%. Within crystals, the peptides formed beta-sheet ribbons, but differences were observed in hydrogen-bonding patterns and side-chain arrangements. These differences were also deduced from temperature dependence of amide protons. Force-field calculations based on the crystal structures indicated that association of beta-sheet ribbons had energy benefits, and it was assumed that molecular aggregation progressed spontaneously. These structural studies indicated the chirality of amino acids affected for the properties of bolaform amides.

  5. Clicked Cinnamic/Caffeic Esters and Amides as Radical Scavengers and 5-Lipoxygenase Inhibitors

    Directory of Open Access Journals (Sweden)

    Jérémie A. Doiron

    2014-01-01

    Full Text Available 5-Lipoxygenase (5-LO is the key enzyme responsible for the conversion of arachidonic acid to leukotrienes, a class of lipid mediators implicated in inflammatory disorders. In this paper, we describe the design, synthesis, and preliminary activity studies of novel clicked caffeic esters and amides as radical scavengers and 5-LO inhibitors. From known 5-LO inhibitor 3 as a lead, cinnamic esters 8a–h and amides 9a–h as well as caffeic esters 15a–h and amides 16a–h were synthesized by Cu(I-catalyzed [1,3]-dipolar cycloaddition with the appropriate azide precursors and terminal alkynes. All caffeic analogs are proved to be good radical scavengers (IC50: 10–20 μM. Esters 15g and 15f possessed excellent 5-LO inhibition activity in HEK293 cells and were equipotent with the known 5-LO inhibitor CAPE and more potent than Zileuton. Several synthesized esters possess activities rivaling Zileuton in stimulated human polymorphonuclear leukocytes.

  6. Identify nature N-acylethanolamide-hydrolyzing acid amide(NAAA)inhibitor: effect of Angelicae Pubescentis Radix on anti-inflammation%独活挥发油对N-脂肪酰基乙醇胺水解酶的抑制作用及抗炎作用研究

    Institute of Scientific and Technical Information of China (English)

    孙文畅; 杨隆河; 邱彦; 任杰; 黄锐; 傅瑾

    2011-01-01

    目的:研究独活挥发油对内源性大麻素水解酶N-脂肪酰基乙醇胺水解酶(N-acylethanolamine-hydrolyzing acid amidase,NAAA)水解活性的影响以及对脂多糖(LPS)诱导的小鼠巨噬细胞RAW264.7炎症反应模型的抗炎作用.方法:采用水蒸气蒸馏法提取独活挥发油,GC-MS检测化学成分;采用LC-MS检测NAAA水解活性;采用LPS诱导RAW264.7细胞建立细胞炎症反应模型;采用LC-MS检测细胞内棕榈酸乙醇胺(N-palmitoylethanolamine,PEA)水平;采用实时定量PCR检测肿瘤坏子因子-α(TNF-α)、诱导型一氧化氮合酶(iNOS)和白细胞介素-6(IL-6)mRNA表达;采用酶联免疫吸附法(ELISA)检测TNF-α含量;采用Griess法检测一氧化氮(NO)含量.结果:独活挥发油可抑制NAAA水解活性,升高LPS诱导的RAW264.7细胞内PEA水平;独活挥发油可下调LPS诱导的RAW264.7细胞炎症因子TNF-α,iNOS,IL-6 mRNA表达;独活挥发油可抑制LPS诱导的RAW264.7细胞TNF-α和NO释放.结论:独活挥发油能够抑制NAAA水解活性,升高细胞内PEA水平,降低炎症因子表达,具有一定的抗炎作用.%Objective: To investigate the effect of Angelicae Pubescentis Radix (APR) on the activity of endocannabinoid hydrolase and N-acylethanolamine-hydrolyzing acid amidase ( NAAA) , and to demonstrate the mechanism of anti-inflammatory effect of APR by in vitro lipopolysaccharide ( LPS) -induced inflammation model. Method: APR essential oil was extracted by steam distillation , and the chemical components were identified by GC-MS. Enzymatic activity was performed by using recombinant NAAA-overex-pressing protein and detected by LC-MS. Lipids were extracted by methonal/chloroform mixure and analyzed by LC-MS. mRNA and protein expression levels of proinflammatory genes were examined by Real time-PCR and ELISA assay kit, respectively. The content of nitro oxide (NO) was detected by Griess reaction. Result: Twenty active components were identified from APR essential

  7. Marine Extremophiles: A Source of Hydrolases for Biotechnological Applications

    OpenAIRE

    Gabriel Zamith Leal Dalmaso; Davis Ferreira; Alane Beatriz Vermelho

    2015-01-01

    The marine environment covers almost three quarters of the planet and is where evolution took its first steps. Extremophile microorganisms are found in several extreme marine environments, such as hydrothermal vents, hot springs, salty lakes and deep-sea floors. The ability of these microorganisms to support extremes of temperature, salinity and pressure demonstrates their great potential for biotechnological processes. Hydrolases including amylases, cellulases, peptidases and lipases from hy...

  8. Diagnosis in bile acid-CoA: Amino acid N-acyltransferase deficiency

    Institute of Scientific and Technical Information of China (English)

    Nedim Had(z)i(c); Laura N Bull; Peter T Clayton; AS Knisely

    2012-01-01

    Cholate-CoA ligase (CCL) and bile acid-CoA:amino acid N-acyltransferase (BAAT) sequentially mediate bile-acid amidation.Defects can cause intrahepatic cholestasis.Distinction has required gene sequencing.We assessed potential clinical utility of immunostaining of liver for CCL and BAAT.Using commercially available antibodies against BAAT and CCL,we immunostained liver from an infant with jaundice,deficiency of amidated bile acids,and transcription-terminating mutation in BAAT.CCL was normally expressed.BAAT expression was not detected.Immunostaining may facilitate diagnosis in bileacid amidation defects.

  9. Hyperbranched Poly(amide-ester) Mildly Synthesized and Its Characterization

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AB2-type-prepolymerized monomer was rapidly (2 h) prepared atIoom temperature (25℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials.By employing toluene-p-sulfonic acid as a catalyzer, a series of hyperbranched poly(amide-ester) (HBPAE) were successfully synthesized from prepared AB2 monomer by solution condensation polymerization through "one-step process" or "pseudo one-step process" (using pen taerythritol as a center core).The processes were carried out at high temperature of 120 C for 6 h in air atmosphere (inert protection free) with reduced pressure distillation (0.08~0.096 MPa).The results of FT-IR, UV-Vis, TGA, and intrinsic viscosity testing by Ubbelodhe viscometer showed that the prepared HBPAEspossess three-dimensional configuration with unsaturated conjugate structure,large numbers of branches and numerous terminal hydroxyl groups.These result in their lowviscosity, high solubility and thermal stability.

  10. A reduced-amide inhibitor of Pin1 binds in a conformation resembling a twisted-amide transition state.

    Science.gov (United States)

    Xu, Guoyan G; Zhang, Yan; Mercedes-Camacho, Ana Y; Etzkorn, Felicia A

    2011-11-08

    The mechanism of the cell cycle regulatory peptidyl prolyl isomerase (PPIase), Pin1, was investigated using reduced-amide inhibitors designed to mimic the twisted-amide transition state. Inhibitors, R-pSer-Ψ[CH(2)N]-Pro-2-(indol-3-yl)ethylamine, 1 [R = fluorenylmethoxycarbonyl (Fmoc)] and 2 (R = Ac), of Pin1 were synthesized and bioassayed. Inhibitor 1 had an IC(50) value of 6.3 μM, which is 4.5-fold better for Pin1 than our comparable ground-state analogue, a cis-amide alkene isostere-containing inhibitor. The change of Fmoc to Ac in 2 improved aqueous solubility for structural determination and resulted in an IC(50) value of 12 μM. The X-ray structure of the complex of 2 bound to Pin1 was determined to 1.76 Å resolution. The structure revealed that the reduced amide adopted a conformation similar to the proposed twisted-amide transition state of Pin1, with a trans-pyrrolidine conformation of the prolyl ring. A similar conformation of substrate would be destabilized relative to the planar amide conformation. Three additional reduced amides, with Thr replacing Ser and l- or d-pipecolate (Pip) replacing Pro, were slightly weaker inhibitors of Pin1.

  11. Amide Link Scission in the Polyamide Active Layers of Thin-Film Composite Membranes upon Exposure to Free Chlorine: Kinetics and Mechanisms.

    Science.gov (United States)

    Powell, Joshua; Luh, Jeanne; Coronell, Orlando

    2015-10-20

    The volume-averaged amide link scission in the aromatic polyamide active layer of a reverse osmosis membrane upon exposure to free chlorine was quantified at a variety of free chlorine exposure times, concentrations, and pH and rinsing conditions. The results showed that (i) hydroxyl ions are needed for scission to occur, (ii) hydroxide-induced amide link scission is a strong function of exposure to hypochlorous acid, (iii) the ratio between amide links broken and chlorine atoms taken up increased with the chlorination pH and reached a maximum of ∼25%, (iv) polyamide disintegration occurs when high free chlorine concentrations, alkaline conditions, and high exposure times are combined, (v) amide link scission promotes further chlorine uptake, and (vi) scission at the membrane surface is unrepresentative of volume-averaged scission in the active layer. Our observations are consistent with previously proposed mechanisms describing amide link scission as a result of the hydrolysis of the N-chlorinated amidic N-C bond due to nucleophilic attack by hydroxyl ions. This study increases the understanding of the physicochemical changes that could occur for membranes in treatment plants using chlorine as an upstream disinfectant and the extent and rate at which those changes would occur.

  12. Application of the Kombucha 'tea fungus' for the enhancement of antioxidant and starch hydrolase inhibitory properties of ten herbal teas.

    Science.gov (United States)

    Watawana, Mindani I; Jayawardena, Nilakshi; Choo, Candy; Waisundara, Viduranga Y

    2016-03-01

    Ten herbal teas (Acacia arabica, Aegle marmelos flower, A. marmelos root bark, Aerva lanata, Asteracantha longifolia, Cassia auriculata, Hemidesmus indicus, Hordeum vulgare, Phyllanthus emblica, Tinospora cordifolia) were fermented with the Kombucha 'tea fungus'. The pH values of the fermented beverages ranged from 4.0 to 6.0 by day 7, while the titratable acidity ranged from 2.5 to 5.0g/mL (Pantioxidant and starch hydrolase inhibitory potential of the herbal teas was observed by adding the tea fungus.

  13. D(-)-二吡啶甲基酒石酸酰胺在不对称氧化合成埃索美拉唑中的应用%Application of D(-)-Di-pyridylmethyl Tartaric Acid Amide in the Synthesis of Esomeprazole through Asymmetric Oxidation

    Institute of Scientific and Technical Information of China (English)

    赵姗姗; 卢华; 张月成; 赵继全

    2012-01-01

    Two di-pyridylmethyl D(-)-tartaric acid amides 2 and 3 were respectively prepared through the reaction of(-)-diethyl D-tartrate(1) with 2-aminomethyl pyridine and 4-aminomethyl pyridine.The compounds 1,2 and 3 coordinated with isopropyl titanate,respectively,were used as catalyst in the asymmetric oxidation of the precursor(Eso-I) of esomeprazole with cumene hydroperoxide(CHP) as oxidant.The results revealed that both the catalytic systems derived from ligand 2 and 3 and isopropyl titanate showed good catalytic activity and enantioselectivity in the synthesis of esomeprazole.For example,the conversion of Eso-I,the selectivity toward to the esomeprazole and the enantio excess reached 84.7%,91.8% and 89.0%,respectively,when 2 was used as the ligand and the reaction was conducted in toluene under the optimized conditions.%D(-)-酒石酸二乙酯(1)分别与2-氨甲基吡啶和4-氨甲基吡啶反应,合成了D(-)-二吡啶甲基酒石酸酰胺2和3.分别以1~3为手性配体与钛酸异丙酯配合,催化过氧化氢异丙苯(CHP)不对称氧化埃索美拉唑前体(Eso-I)合成埃索美拉唑.结果表明,由配体2或3构成的催化体系在埃索美拉唑合成上显示出较高的催化活性和对映选择性.例如,当以2为配体,甲苯为溶剂,在优化的条件下进行反应时,Eso-I的转化率达84.7%,埃索美拉唑的选择性达91.8%,对映体过量值达89.0%.

  14. Copper/N,N-Dimethylglycine Catalyzed Goldberg Reactions Between Aryl Bromides and Amides, Aryl Iodides and Secondary Acyclic Amides

    Directory of Open Access Journals (Sweden)

    Liqin Jiang

    2014-08-01

    Full Text Available An efficient and general copper-catalyzed Goldberg reaction at 90–110 °C between aryl bromides and amides providing the desired products in good to excellent yields has been developed using N,N-dimethylglycine as the ligand. The reaction is tolerant toward a wide range of amides and a variety of functional group substituted aryl bromides. In addition, hindered, unreactive aromatic and aliphatic secondary acyclic amides, known to be poor nucleophiles, are efficiently coupled with aryl iodides through this simple and cheap copper/N,N-dimethylglycine catalytic system.

  15. A specific acid [alpha]-glucosidase in lamellar bodies of the human lung

    NARCIS (Netherlands)

    Vries, A.C.J. de; Schram, A.W.; Tager, J.M.; Batenburg, J.J.

    2006-01-01

    In the present investigation, we have demonstrated that three lysosomal-type hydrolases, alpha-glucosidase, alpha-mannosidase and a phosphatase, are present in lamellar bodies isolated from adult human lung. The hydrolase activities that were studied, all showed an acidic pH optimum, which is charac

  16. Inhibition of fatty acid binding proteins elevates brain anandamide levels and produces analgesia.

    Directory of Open Access Journals (Sweden)

    Martin Kaczocha

    Full Text Available The endocannabinoid anandamide (AEA is an antinociceptive lipid that is inactivated through cellular uptake and subsequent catabolism by fatty acid amide hydrolase (FAAH. Fatty acid binding proteins (FABPs are intracellular carriers that deliver AEA and related N-acylethanolamines (NAEs to FAAH for hydrolysis. The mammalian brain expresses three FABP subtypes: FABP3, FABP5, and FABP7. Recent work from our group has revealed that pharmacological inhibition of FABPs reduces inflammatory pain in mice. The goal of the current work was to explore the effects of FABP inhibition upon nociception in diverse models of pain. We developed inhibitors with differential affinities for FABPs to elucidate the subtype(s that contributes to the antinociceptive effects of FABP inhibitors. Inhibition of FABPs reduced nociception associated with inflammatory, visceral, and neuropathic pain. The antinociceptive effects of FABP inhibitors mirrored their affinities for FABP5, while binding to FABP3 and FABP7 was not a predictor of in vivo efficacy. The antinociceptive effects of FABP inhibitors were mediated by cannabinoid receptor 1 (CB1 and peroxisome proliferator-activated receptor alpha (PPARα and FABP inhibition elevated brain levels of AEA, providing the first direct evidence that FABPs regulate brain endocannabinoid tone. These results highlight FABPs as novel targets for the development of analgesic and anti-inflammatory therapeutics.

  17. MICROBIAL DEGRADATION OF SEVEN AMIDES BY SUSPENDED BACTERIAL POPULATIONS

    Science.gov (United States)

    Microbial transformation rate constants were determined for seven amides in natural pond water. A second-order mathematical rate expression served as the model for describing the microbial transformation. Also investigated was the relationship between the infrared spectra and the...

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

    Science.gov (United States)

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

    2014-11-18

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

  19. SYNTHESIS AND BIOLOGICAL ACTIVITY OF AMIDE DERIVATIVES OF GINKGOLIDE A

    Institute of Scientific and Technical Information of China (English)

    LI-HONG HU; ZHONG-LIANG CHEN; YU-YUAN XIE

    2001-01-01

    Amide derivatives of ginkgolide A were prepared and evaluated for their in vitro ability to inhibit the PAF-induced aggregation of rabbit platelets. They showed less activities than their parent compound ginkgolide A.

  20. Amid the Economic Rubble,Shangkong will Rise

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Two years ago, bankers and policymakers were arguing heatedly over whether New York or London was the world's premier financial centre. Amid the post-crisis rubble that covers both cities, those arguments now look terribly passé.

  1. Biodegradable gadolinium-chelated cationic poly(urethane amide) copolymers for gene transfection and magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Xiaolong [Department of Radiology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065 (China); Wang, Gangmin [Department of Urology, Huashan Hospital, Fudan University, Shanghai 200040 (China); Shi, Ting [The Institute for Translational Nanomedicine, Shanghai East Hospital, Institute for Biomedical Engineering and Nanoscience, Tongji University School of Medicine, Shanghai 200092 (China); Shao, Zhihong [Department of Radiology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065 (China); Zhao, Peng; Shi, Donglu [The Institute for Translational Nanomedicine, Shanghai East Hospital, Institute for Biomedical Engineering and Nanoscience, Tongji University School of Medicine, Shanghai 200092 (China); Ren, Jie [Institute of Nano and Biopolymeric Materials, School of Materials Science and Engineering, Tongji University, 4800 Caoan Road, Shanghai 201804 (China); Lin, Chao, E-mail: chaolin@tongji.edu.cn [The Institute for Translational Nanomedicine, Shanghai East Hospital, Institute for Biomedical Engineering and Nanoscience, Tongji University School of Medicine, Shanghai 200092 (China); Wang, Peijun, E-mail: tjpjwang@sina.com [Department of Radiology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065 (China)

    2016-08-01

    Theranostic nano-polyplexes containing gene and imaging agents hold a great promise for tumor diagnosis and therapy. In this work, we develop a group of new gadolinium (Gd)-chelated cationic poly(urethane amide)s for gene delivery and T{sub 1}-weighted magnetic resonance (MR) imaging. Cationic poly(urethane amide)s (denoted as CPUAs) having multiple disulfide bonds, urethane and amide linkages were synthesized by stepwise polycondensation reaction between 1,4-bis(3-aminopropyl)piperazine and a mixture of di(4-nitrophenyl)-2, 2′-dithiodiethanocarbonate (DTDE-PNC) and diethylenetriaminepentaacetic acid (DTPA) dianhydride at varied molar ratios. Then, Gd-chelated CPUAs (denoted as GdCPUAs) were produced by chelating Gd(III) ions with DTPA residues of CPUAs. These GdCPUAs could condense gene into nanosized and positively-charged polyplexes in a physiological condition and, however, liberated gene in an intracellular reductive environment. In vitro transfection experiments revealed that the GdCPUA at a DTDE-PNC/DTPA residue molar ratio of 85/15 induced the highest transfection efficiency in different cancer cells. This efficiency was higher than that yielded with 25 kDa branched polyethylenimine as a positive control. GdCPUAs and their polyplexes exhibited low cytotoxicity when an optimal transfection activity was detected. Moreover, GdCPUAs may serve as contrast agents for T{sub 1}-weighted magnetic resonance imaging. The results of this work indicate that biodegradable Gd-chelated cationic poly(urethane amide) copolymers have high potential for tumor theranostics. - Highlights: • Novel cationic gadolinium-chelated poly(urethane amide)s (GdCPUAs) are prepared. • GdCPUAs can induce a high transfection efficacy in different cancer cells. • GdCPUAs reveal good cyto-compatibility against cancer cells. • GdCPUAs may be applied as T{sub 1}-contrast agents for magnetic resonance imaging. • GdCPUAs hold high potential for cancer theranostics.

  2. Phase space investigation of the lithium amide halides

    Energy Technology Data Exchange (ETDEWEB)

    Davies, Rosalind A. [Hydrogen Storage Chemistry Group, School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Hydrogen and Fuel Cell Group, School of Chemical Engineering, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Hewett, David R.; Korkiakoski, Emma [Hydrogen Storage Chemistry Group, School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Thompson, Stephen P. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Anderson, Paul A., E-mail: p.a.anderson@bham.ac.uk [Hydrogen Storage Chemistry Group, School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2015-10-05

    Highlights: • The lower limits of halide incorporation in lithium amide have been investigated. • The only amide iodide stoichiometry observed was Li{sub 3}(NH{sub 2}){sub 2}I. • Solid solutions were observed in both the amide chloride and amide bromide systems. • A 46% reduction in chloride content resulted in a new phase: Li{sub 7}(NH{sub 2}){sub 6}Cl. • New low-chloride phase maintained improved H{sub 2} desorption properties of Li{sub 4}(NH{sub 2}){sub 3}Cl. - Abstract: An investigation has been carried out into the lower limits of halide incorporation in lithium amide (LiNH{sub 2}). It was found that the lithium amide iodide Li{sub 3}(NH{sub 2}){sub 2}I was unable to accommodate any variation in stoichiometry. In contrast, some variation in stoichiometry was accommodated in Li{sub 7}(NH{sub 2}){sub 6}Br, as shown by a decrease in unit cell volume when the bromide content was reduced. The amide chloride Li{sub 4}(NH{sub 2}){sub 3}Cl was found to adopt either a rhombohedral or a cubic structure depending on the reaction conditions. Reduction in chloride content generally resulted in a mixture of phases, but a new rhombohedral phase with the stoichiometry Li{sub 7}(NH{sub 2}){sub 6}Cl was observed. In comparison to LiNH{sub 2}, this new low-chloride phase exhibited similar improved hydrogen desorption properties as Li{sub 4}(NH{sub 2}){sub 3}Cl but with a much reduced weight penalty through addition of chloride. Attempts to dope lithium amide with fluoride ions have so far proved unsuccessful.

  3. Artists with Arthritis Create Beauty amid Pain

    Institute of Scientific and Technical Information of China (English)

    Alan; Mozes; 蔡峥伟

    2000-01-01

    得此来稿,我们曾犹豫再三,是否刊用此文。因为,其内容给人的第一印象颇有点离奇。Artists with Arthritis Create Beauty amid Pain,怎么可能呢?细读之下,你也许会觉得,此文虽是一家之言,但也并非荒唐。尤其是本文的收尾句,笔锋一转,抖出了妙言: ...in addition to the emotional support such stories can give RA patients,there are now new drug options that far surpass the treatment choices Renoir faced. 此句是否可译:除了此类故事能够给患风湿病者一种情感上的支持之外,现在可选的新药要比Renoir(雷诺阿,法国印象派画家。主要作品有《包厢》、《游船上的午餐》、《浴女》等。)时代强得多。

  4. Pharmacokinetics and metabolism studies on the glucagon-like peptide-1 (GLP-1)-derived metabolite GLP-1(9-36)amide in male Beagle dogs.

    Science.gov (United States)

    Eng, Heather; Sharma, Raman; McDonald, Thomas S; Landis, Margaret S; Stevens, Benjamin D; Kalgutkar, Amit S

    2014-09-01

    Glucagon-like peptide-1 (GLP-1)(7-36)amide is a 30-amino acid peptide hormone that is secreted from intestinal enteroendocrine L-cells in response to nutrients. GLP-1(7-36)amide possesses potent insulinotropic actions in the augmentation of glucose-dependent insulin secretion. GLP-1(7-36)amide is rapidly metabolized by dipeptidyl peptidase-IV to yield GLP-1(9-36)amide as the principal metabolite. Contrary to the earlier notion that peptide cleavage products of native GLP-1(7-36)amide [including GLP-1(9-36)amide] are pharmacologically inactive, recent studies have demonstrated cardioprotective and insulinomimetic effects with GLP-1(9-36)amide in mice, dogs and humans. In the present work, in vitro metabolism and pharmacokinetic properties of GLP-1(9-36)amide have been characterized in dogs, since this preclinical species has been used as an animal model to demonstrate the in vivo vasodilatory and cardioprotective effects of GLP-1(9-36)amide. A liquid chromatography tandem mass spectrometry assay was developed for the quantitation of the intact peptide in hepatocyte incubations as opposed to a previously reported enzyme-linked immunosorbent assay. Although GLP-1(9-36)amide was resistant to proteolytic cleavage in dog plasma and bovine serum albumin (t1/2>240 min), the peptide was rapidly metabolized in dog hepatocytes with a t1/2 of 110 min. Metabolite identification studies in dog hepatocytes revealed a variety of N-terminus cleavage products, most of which, have also been observed in human and mouse hepatocytes. Proteolysis at the C-terminus was not observed in GLP-1(9-36)amide. Following the administration of a single intravenous bolus dose (20 µg/kg) to male Beagle dogs, GLP-1(9-36)amide exhibited a mean plasma clearance of 15 ml/min/kg and a low steady state distribution volume of 0.05 l/kg, which translated into a short elimination half life of 0.05 h. Following subcutaneous administration of GLP-1(9-36)amide at 50 µg/kg, systemic exposure of

  5. The gram-negative bacterium Azotobacter chroococcum NCIMB 8003 employs a new glycoside hydrolase family 70 4,6-α-glucanotransferase enzyme (GtfD) to synthesize a reuteran like polymer from maltodextrins and starch

    NARCIS (Netherlands)

    Gangoiti, Joana; van Leeuwen, Sander S; Vafiadi, Christina; Dijkhuizen, Lubbert

    2016-01-01

    BACKGROUND: Originally the glycoside hydrolase (GH) family 70 only comprised glucansucrases of lactic acid bacteria which synthesize α-glucan polymers from sucrose. Recently we have identified 2 novel subfamilies of GH70 enzymes represented by the Lactobacillus reuteri 121 GtfB and the Exiguobacteri

  6. Purification and characterization of a novel chlorpyrifos hydrolase from Cladosporium cladosporioides Hu-01.

    Science.gov (United States)

    Gao, Yan; Chen, Shaohua; Hu, Meiying; Hu, Qiongbo; Luo, Jianjun; Li, Yanan

    2012-01-01

    Chlorpyrifos is of great environmental concern due to its widespread use in the past several decades and its potential toxic effects on human health. Thus, the degradation study of chlorpyrifos has become increasing important in recent years. A fungus capable of using chlorpyrifos as the sole carbon source was isolated from organophosphate-contaminated soil and characterized as Cladosporium cladosporioides Hu-01 (collection number: CCTCC M 20711). A novel chlorpyrifos hydrolase from cell extract was purified 35.6-fold to apparent homogeneity with 38.5% overall recovery by ammoniumsulfate precipitation, gel filtration chromatography and anion-exchange chromatography. It is a monomeric structure with a molecular mass of 38.3 kDa. The pI value was estimated to be 5.2. The optimal pH and temperature of the purified enzyme were 6.5 and 40°C, respectively. No cofactors were required for the chlorpyrifos-hydrolysis activity. The enzyme was strongly inhibited by Hg²⁺, Fe³⁺, DTT, β-mercaptoethanol and SDS, whereas slight inhibitory effects (5-10% inhibition) were observed in the presence of Mn²⁺, Zn²⁺, Cu²⁺, Mg²⁺, and EDTA. The purified enzyme hydrolyzed various organophosphorus insecticides with P-O and P-S bond. Chlorpyrifos was the preferred substrate. The Km and Vmax values of the enzyme for chlorpyrifos were 6.7974 μM and 2.6473 μmol·min⁻¹, respectively. Both NH2-terminal sequencing and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometer (MALDI-TOF-MS) identified an amino acid sequence MEPDGELSALTQGANS, which shared no similarity with any reported organophosphate-hydrolyzing enzymes. These results suggested that the purified enzyme was a novel hydrolase and might conceivably be developed to fulfill the practical requirements to enable its use in situ for detoxification of chlorpyrifos. Finally, this is the first described chlorpyrifos hydrolase from fungus.

  7. Nonplanar tertiary amides in rigid chiral tricyclic dilactams. Peptide group distortions and vibrational optical activity.

    Science.gov (United States)

    Pazderková, Markéta; Profant, Václav; Hodačová, Jana; Sebestík, Jaroslav; Pazderka, Tomáš; Novotná, Pavlína; Urbanová, Marie; Safařík, Martin; Buděšínský, Miloš; Tichý, Miloš; Bednárová, Lucie; Baumruk, Vladimír; Maloň, Petr

    2013-08-22

    We investigate amide nonplanarity in vibrational optical activity (VOA) spectra of tricyclic spirodilactams 5,8-diazatricyclo[6,3,0,0(1,5)]undecan-4,9-dione (I) and its 6,6',7,7'-tetradeuterio derivative (II). These rigid molecules constrain amide groups to nonplanar geometries with twisted pyramidal arrangements of bonds to amide nitrogen atoms. We have collected a full range vibrational circular dichroism (VCD) and Raman optical activity (ROA) spectra including signals of C-H and C-D stretching vibrations. We report normal-mode analysis and a comparison of calculated to experimental VCD and ROA. The data provide band-to-band assignment and offer a possibility to evaluate roles of constrained nonplanar tertiary amide groups and rigid chiral skeletons. Nonplanarity shows as single-signed VCD and ROA amide I signals, prevailing the couplets expected to arise from the amide-amide interaction. Amide-amide coupling dominates amide II (mainly C'-N stretching, modified in tertiary amides by the absence of a N-H bond) transitions (strong couplet in VCD, no significant ROA) probably due to the close proximity of amide nitrogen atoms. At lower wavenumbers, ROA spectra exhibit another likely manifestation of amide nonplanarity, showing signals of amide V (δ(oop)(N-C) at ~570 cm(-1)) and amide VI (δ(oop)(C'═O) at ~700 cm(-1) and ~650 cm(-1)) vibrations.

  8. Altered soluble epoxide hydrolase-derived oxylipins in patients with seasonal major depression: An exploratory study.

    Science.gov (United States)

    Hennebelle, Marie; Otoki, Yurika; Yang, Jun; Hammock, Bruce D; Levitt, Anthony J; Taha, Ameer Y; Swardfager, Walter

    2017-02-27

    Many cytochrome p450-derived lipids promote resolution of inflammation, in contrast to their soluble epoxide hydrolase(sEH)-derived oxylipin breakdown products. Here we compare plasma oxylipins and precursor fatty acids between seasons in participants with major depressive disorder with seasonal pattern (MDD-s). Euthymic participants with a history of MDD-s recruited in summer-fall were followed-up in winter. At both visits, a structured clinical interview (DSM-5 criteria) and the Beck Depression Inventory II (BDI-II) were administered. Unesterified and total oxylipin pools were assayed by liquid chromatography tandem mass-spectrometry (LC-MS/MS). Precursor fatty acids were measured by gas chromatography. In nine unmedicated participants euthymic at baseline who met depression criteria in winter, BDI-II scores increased from 4.9±4.4 to 19.9±7.7. Four sEH-derived oxylipins increased in winter compared to summer-fall with moderate to large effect sizes. An auto-oxidation product (unesterified epoxyketooctadecadienoic acid) and lipoxygenase-derived 13-hydroxyoctadecadienoic acid also increased in winter. The cytochrome p450-derived 20-COOH-leukotriene B4 (unesterified) and total 14(15)-epoxyeicosatetraenoic acid, and the sEH-derived 14,15-dihydroxyeicostrienoic acid (unesterified), decreased in winter. We conclude that winter depression was associated with changes in cytochrome p450- and sEH-derived oxylipins, suggesting that seasonal shifts in omega-6 and omega-3 fatty acid metabolism mediated by sEH may underlie inflammatory states in symptomatic MDD-s.

  9. Dianthosaponins A-F, triterpene saponins, flavonoid glycoside, aromatic amide glucoside and γ-pyrone glucoside from Dianthus japonicus.

    Science.gov (United States)

    Nakano, Takahiro; Sugimoto, Sachiko; Matsunami, Katsuyoshi; Otsuka, Hideaki

    2011-01-01

    From aerial parts of Dianthus japonicus, six new and seven known oleanane-type triterpene saponins were isolated. The structures of the new saponins, named dianthosaponins A-F, were elucidated by means of high resolution mass spectrometry, and extensive inspection of one- and two-dimensional NMR spectroscopic data. A new C-glycosyl flavone, a glycosidic derivative of anthranilic acid amide and a maltol glucoside were also isolated.

  10. Cations bind only weakly to amides in aqueous solutions.

    Science.gov (United States)

    Okur, Halil I; Kherb, Jaibir; Cremer, Paul S

    2013-04-01

    We investigated salt interactions with butyramide as a simple mimic of cation interactions with protein backbones. The experiments were performed in aqueous metal chloride solutions using two spectroscopic techniques. In the first, which provided information about contact pair formation, the response of the amide I band to the nature and concentration of salt was monitored in bulk aqueous solutions via attenuated total reflection Fourier transform infrared spectroscopy. It was found that molar concentrations of well-hydrated metal cations (Ca(2+), Mg(2+), Li(+)) led to the rise of a peak assigned to metal cation-bound amides (1645 cm(-1)) and a decrease in the peak associated with purely water-bound amides (1620 cm(-1)). In a complementary set of experiments, the effect of cation identity and concentration was investigated at the air/butyramide/water interface via vibrational sum frequency spectroscopy. In these studies, metal ion-amide binding led to the ordering of the adjacent water layer. Such experiments were sensitive to the interfacial partitioning of cations in either a contact pair with the amide or as a solvent separated pair. In both experiments, the ordering of the interactions of the cations was: Ca(2+) > Mg(2+) > Li(+) > Na(+) ≈ K(+). This is a direct cationic Hofmeister series. Even for Ca(2+), however, the apparent equilibrium dissociation constant of the cation with the amide carbonyl oxygen was no tighter than ∼8.5 M. For Na(+) and K(+), no evidence was found for any binding. As such, the interactions of metal cations with amides are far weaker than the analogous binding of weakly hydrated anions.

  11. Enzymatic synthesis oF L-tryptophan from D,L-2-amino-delta2-thiazoline-4-carboxylic acid and indole by Pseudomonas sp. TS1138 L-2-amino-delta2-thiazoline-4-carboxylic acid hydrolase, S-carbamyl-L-cysteine amidohydrolase, and Escherichia coli L-tryptophanase.

    Science.gov (United States)

    Du, J; Duan, J J; Zhang, Q; Hou, J; Bai, F; Chen, N; Bai, G

    2012-01-01

    L-Tryptophan (L-Trp) is an essential amino acid. It is widely used in medical, health and food products, so a low-cost supply is needed. There are 4 methods for L-Trp production: chemical synthesis, extraction, enzymatic synthesis, and fermentation. In this study, we produced a recombinant bacterial strain pET-tnaA of Escherichia coli which has the L-tryptophanase gene. Using the pET-tnaA E. coli and the strain TS1138 of Pseudomonas sp., a one-pot enzymatic synthesis of L-Trp was developed. Pseudomonas sp. TS1138 was added to a solution of D,L-2-amino-delta2-thiazoline-4-carboxylic acid (DL-ATC) to convert it to L-cysteine (L-Cys). After concentration, E. coli BL21 (DE 3) cells including plasmid pET-tnaA, indole, and pyridoxal 5'-phosphate were added. At the optimum conditions, the conversion rates of DL-ATC and L-Cys were 95.4% and 92.1%, respectively. After purifying using macroporous resin S8 and NKA-II, 10.32 g of L-Trp of 98.3% purity was obtained. This study established methods for one-pot enzymatic synthesis and separation of L-Trp. This method of producing L-Trp is more environmentally sound than methods using chemical synthesis, and it lays the foundations for industrial production of L-Trp from DL-ATC and indole.

  12. Purification and characterization of an arginine ester hydrolase from the venom of Trimeresurus mucrosqumatus in Hunan province of China

    Institute of Scientific and Technical Information of China (English)

    YU Xiao-dong; LI Bo; YU Zheng-ping

    2005-01-01

    Objective: To study the physical and chemical properties of an arginine ester hydrolase from the venom of Trimeresurus mucrosqumatus in Hunan province of China. Methods :The arginine ester hydrolase (AEH) was isolated from the venom of Chinese Trimeresurus mucrosqumatus by a combination of ionexchange chromatography on DEAE-Sephadex A-50, CM-Sepharose Cl-6B and gel filtration on Sephadex G-100. Results: The purified protein named TM-AEH,a glycoprotein with carbohydrate content of 0.5 % neutral hexose and 0. 75 % sialic acid,a relative molecular mass of 29.0 kDa,and an isoelectric point (pI) of 5. 2. It shares with an extinction coefficient (E0.1%/cm) of 1.332 at 280 nm,consisted of 225 amino acid residues ,and migrated as a band under reduced or non-reduced condition in basic PAGE. TM-AEH was a highly thermostable protein and was stable to pH changes between 5 and 9. The optimum temperature and optimum pH were 55℃ and 8. 4 for its catalytic activity respectively,which was inhibited by Fe3+ and Cu2+. Conclusion:This protein can exhibit higher BAEE-hydrolysing activity and fibrinogenolytic activity as compared to that of whole venom.

  13. Application of cyclic ketones in MCR: Ugi/amide coupling based synthesis of fused tetrazolo[1,5-a][1,4]benzodiazepines

    NARCIS (Netherlands)

    Yerande, Swapnil; Newase, Kiran; Singh, Bhawani; Boltjes, André; Dömling, Alex

    2014-01-01

    Azido-Ugi reaction involving cyclic ketone, primary amine, isonitrile, and azide afforded substituted tetrazole derivatives 5. These intermediates were hydrolyzed to corresponding acid derivatives. EDAC/HOBt mediated amide bond formation of 5 gave fused tetrazolo[1,5-a][1,4]benzodiazepine 6 in high

  14. Catalytic Oxidation of Catechol at Gold Nanoparticles/Graphene/Thioctic Acid Amide-Modified Gold Electrode%纳米金/石墨烯/硫辛酰胺修饰的金电极对儿茶酚的催化氧化

    Institute of Scientific and Technical Information of China (English)

    王娜; 李献锐; 王贝贝; 赵海燕; 籍雪平

    2016-01-01

    利用电化学还原的方法将还原氧化石墨烯(ERGO)和纳米金(AuNPs)电沉积到硫辛酰胺(T‐NH2)修饰的金电极表面,研究了儿茶酚在该修饰电极上的电化学行为.实验表明,在0.10mol/L磷酸缓冲(pH=7.0)溶液中,该修饰电极对儿茶酚具有良好的电催化作用,儿茶酚氧化峰电位比未修饰的金电极负移了80mV,氧化还原峰电流增大很多,响应电流与儿茶酚浓度在1.40×10-6~9.42×10-3mol/L范围内呈良好的线性关系,检测的灵敏度为2682.8μA・(mmol/L)/cm2,检测下限为7.00×10-7mol/L.此电极具有较好的重现性和稳定性.对样品进行测定及加标回收实验,回收率在97.3%~103.0%之间.%Based on direct electrodeposition of electrochemically reduced graphene oxide (ERGO)‐Au nano‐particles (AuNPs) on thioctic acid amide (T‐NH2 ) self‐assembled monolayers ,a novel electrochemical sensor (SAMs)‐modified gold electrode has been developed for the electrochemical response of catechol (CT) .The modified electrode shows an excellent catalysis for catechol oxidation in a 0.10 mol/L phos‐phate buffer solution (pH 7.0) .The peak potential shifts negatively to 80 mV on the modified gold elec‐trode compared with the unmodified gold electrode ,and the anodic and cathodic currents increase obvious‐ly .The current value is in a good linear relationship with catechol concentration over the range of 1.40 × 10-6 mol/L to 9.42 × 10-3 mol/L .The sensitivity is 2 682.8μA・(mmol/L)/cm2 and the detection limit is 7.00 × 10-7 mol/L .The electrode has a satisfactory reproducibility and stability .This method has been successfully used in the determination of catechol in injection with the recovery between 97.3% -103.0% .

  15. N-(3-Methylphenylsuccinamic acid

    Directory of Open Access Journals (Sweden)

    B. Thimme Gowda

    2010-02-01

    Full Text Available In the crystal structure of the title compound, C11H13NO3, the conformations of the N—H and C=O bonds in the amide segment are anti to each other, and that of the amide H atom is anti to the meta-methyl group in the benzene ring. Furthermore, the conformations of the amide oxygen and the carbonyl O atom of the acid segment are also anti to the adjacent –CH2 groups. The C=O and O—H bonds of the acid group are syn to each other. In the crystal, the molecules are packed into infinite chains through intermolecular N—H...O and O—H...O hydrogen bonds.

  16. Iron(III) Chloride mediated reduction of Bis(1-isoquinolylcarbonyl)amide to an Amide

    Indian Academy of Sciences (India)

    Rojalin Sahu; Papuli Chaliha; Vadivelu Manivannan

    2016-01-01

    In methanol, FeCl3 reacted readily with L1H (L1H = bis(1-isoquinolylcarbonyl)amide) and afforded a complex having the formula [Fe(L2)Cl2] (1) {L2− = -((1-isoquinolyl)(methoxy)methyl)isoquinoline-1-carboxamide ion}. This reaction involves reduction of one of the two carbonyl groups present in L1H to (methoxy)methyl group. A plausible mechanism for the conversion of L1H to L2− has been proposed. Determination of molecular structure of 1 confirmed this conversion. Fe(III) ion is surrounded by three nitrogen atoms of the ligand and two chloride ions, imparting a rare distorted trigonal bipyramidal N3Cl2 coordination environment.

  17. Impact of the Staphylococcus epidermidis LytSR two-component regulatory system on murein hydrolase activity, pyruvate utilization and global transcriptional profile

    Directory of Open Access Journals (Sweden)

    Yu Fangyou

    2010-11-01

    Full Text Available Abstract Background Staphylococcus epidermidis has emerged as one of the most important nosocomial pathogens, mainly because of its ability to colonize implanted biomaterials by forming a biofilm. Extensive studies are focused on the molecular mechanisms involved in biofilm formation. The LytSR two-component regulatory system regulates autolysis and biofilm formation in Staphylococcus aureus. However, the role of LytSR played in S. epidermidis remained unknown. Results In the present study, we demonstrated that lytSR knock-out in S. epidermidis did not alter susceptibility to Triton X-100 induced autolysis. Quantitative murein hydrolase assay indicated that disruption of lytSR in S. epidermidis resulted in decreased activities of extracellular murein hydrolases, although zymogram showed no apparent differences in murein hydrolase patterns between S. epidermidis strain 1457 and its lytSR mutant. Compared to the wild-type counterpart, 1457ΔlytSR produced slightly more biofilm, with significantly decreased dead cells inside. Microarray analysis showed that lytSR mutation affected the transcription of 164 genes (123 genes were upregulated and 41 genes were downregulated. Specifically, genes encoding proteins responsible for protein synthesis, energy metabolism were downregulated, while genes involved in amino acid and nucleotide biosynthesis, amino acid transporters were upregulated. Impaired ability to utilize pyruvate and reduced activity of arginine deiminase was observed in 1457ΔlytSR, which is consistent with the microarray data. Conclusions The preliminary results suggest that in S. epidermidis LytSR two-component system regulates extracellular murein hydrolase activity, bacterial cell death and pyruvate utilization. Based on the microarray data, it appears that lytSR inactivation induces a stringent response. In addition, LytSR may indirectly enhance biofilm formation by altering the metabolic status of the bacteria.

  18. Photophysical studies on the interaction of amides with Bovine Serum Albumin (BSA) in aqueous solution: Fluorescence quenching and protein unfolding

    Energy Technology Data Exchange (ETDEWEB)

    Kumaran, R., E-mail: kumaranwau@rediffmail.com [Department of Chemistry, Dwaraka Doss Goverdhan Doss Vaishnav College, Arumbakkam, Chennai 600106 (India); Ramamurthy, P. [National Centre for Ultrafast Processes, University of Madras, Sekhizar Campus, Taramani, Chennai 600113 (India)

    2014-04-15

    Addition. of amides containing a H-CO(NH{sub 2}) or CH{sub 3}-CO(NH{sub 2}) framework to BSA results in a fluorescence quenching. On the contrary, fluorescence enhancement with a shift in the emission maximum towards the blue region is observed on the addition of dimethylformamide (DMF) (H-CON(CH{sub 3}){sub 2}). Fluorescence quenching accompanied initially with a shift towards the blue region and a subsequent red shift in the emission maximum of BSA is observed on the addition of formamide (H-CO(NH{sub 2})), whereas a shift in the emission maximum only towards the red region results on the addition of acetamide (CH{sub 3}-CONH{sub 2}). Steady state emission spectral studies reveal that amides that possess a free NH{sub 2} and N(CH{sub 3}){sub 2} moiety result in fluorescence quenching and enhancement of BSA respectively. The 3D contour spectral studies of BSA with formamide exhibit a shift in the emission towards the red region accompanied with fluorescence quenching, which indicates that the tryptophan residues of the BSA are exposed to a more polar environment. Circular Dichroism (CD) studies of BSA with amides resulted in a gradual decrease in the α-helical content of BSA at 208 nm, which confirms that there is a conformational change in the native structure of BSA. Time-resolved fluorescence studies illustrate that the extent of buried trytophan moieties exposed to the aqueous phase on the addition of amides follows the order DMFamides. Amides act as a hydrogen-bonding donor and acceptor resulting in a hydrogen-bonding interaction with amino and carboxy moieties (amino acids) present in BSA. The fact that the –NH{sub 2} hydrogen and the carbonyl oxygen of amide form a concerted hydrogen-bonding network with the carbonyl oxygen and the amino moieties of amino acids respectively is established from fluorescence methods. -- Highlights:

  19. Acetylcarnitine hydrolase activity in bovine caudal epididymal spermatozoa

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, K.; Foster, R.A.; Casillas, E.R.

    1986-05-01

    Recently, the authors identified mM concentrations of acetylcarnitine in epidiymal fluids and have investigated the metabolism of acetylcarnitine by bovine and hamster caudal epididymal spermatozoa. (1-/sup 14/C)acetyl-L-carnitine is oxidized to /sup 14/CO/sub 2/ by washed, intact hamster and bovine sperm at maximal rates of 8.4 and 15.2 nmol/hr/10/sup 7/ cells respectively. Conversely, the carnitine moiety of acetyl-L-(/sup 3/H-methyl)carnitine is not accumulated by sperm under similar conditions. Hydrolysis of (/sup 3/H)acetyl-L-carnitine and competition of uptake of (/sup 3/H)acetate by unlabeled acetate was demonstrated in incubations of intact cells of both species. The amount of (/sup 3/H)acetate accumulated in the incubation medium is time-dependent and also depends on the concentration of unlabeled acetate. A partial solubilization of acetylcarnitine hydrolase activity from washed, intact bovine caudal epididymal spermatozoa in buffer or 0.01% Triton X-100 is observed. There is an enrichment of acetylcarnitine hydrolase activity in purified plasma membranes from bovine caudal epididymal spermatozoa when compared to the activity present in broken cell preparations or other cellular fractions. The results suggest that acetylcarnitine is a substrate for spermatozoa as they traverse the epididymis.

  20. Marine Extremophiles: A Source of Hydrolases for Biotechnological Applications

    Directory of Open Access Journals (Sweden)

    Gabriel Zamith Leal Dalmaso

    2015-04-01

    Full Text Available The marine environment covers almost three quarters of the planet and is where evolution took its first steps. Extremophile microorganisms are found in several extreme marine environments, such as hydrothermal vents, hot springs, salty lakes and deep-sea floors. The ability of these microorganisms to support extremes of temperature, salinity and pressure demonstrates their great potential for biotechnological processes. Hydrolases including amylases, cellulases, peptidases and lipases from hyperthermophiles, psychrophiles, halophiles and piezophiles have been investigated for these reasons. Extremozymes are adapted to work in harsh physical-chemical conditions and their use in various industrial applications such as the biofuel, pharmaceutical, fine chemicals and food industries has increased. The understanding of the specific factors that confer the ability to withstand extreme habitats on such enzymes has become a priority for their biotechnological use. The most studied marine extremophiles are prokaryotes and in this review, we present the most studied archaea and bacteria extremophiles and their hydrolases, and discuss their use for industrial applications.

  1. Degradation of Polyester Polyurethane by Bacterial Polyester Hydrolases

    Directory of Open Access Journals (Sweden)

    Juliane Schmidt

    2017-02-01

    Full Text Available Polyurethanes (PU are widely used synthetic polymers. The growing amount of PU used industrially has resulted in a worldwide increase of plastic wastes. The related environmental pollution as well as the limited availability of the raw materials based on petrochemicals requires novel solutions for their efficient degradation and recycling. The degradation of the polyester PU Impranil DLN by the polyester hydrolases LC cutinase (LCC, TfCut2, Tcur1278 and Tcur0390 was analyzed using a turbidimetric assay. The highest hydrolysis rates were obtained with TfCut2 and Tcur0390. TfCut2 also showed a significantly higher substrate affinity for Impranil DLN than the other three enzymes, indicated by a higher adsorption constant K. Significant weight losses of the solid thermoplastic polyester PU (TPU Elastollan B85A-10 and C85A-10 were detected as a result of the enzymatic degradation by all four polyester hydrolases. Within a reaction time of 200 h at 70 °C, LCC caused weight losses of up to 4.9% and 4.1% of Elastollan B85A-10 and C85A-10, respectively. Gel permeation chromatography confirmed a preferential degradation of the larger polymer chains. Scanning electron microscopy revealed cracks at the surface of the TPU cubes as a result of enzymatic surface erosion. Analysis by Fourier transform infrared spectroscopy indicated that the observed weight losses were a result of the cleavage of ester bonds of the polyester TPU.

  2. VCD Robustness of the Amide-I and Amide-II Vibrational Modes of Small Peptide Models.

    Science.gov (United States)

    Góbi, Sándor; Magyarfalvi, Gábor; Tarczay, György

    2015-09-01

    The rotational strengths and the robustness values of amide-I and amide-II vibrational modes of For(AA)n NHMe (where AA is Val, Asn, Asp, or Cys, n = 1-5 for Val and Asn; n = 1 for Asp and Cys) model peptides with α-helix and β-sheet backbone conformations were computed by density functional methods. The robustness results verify empirical rules drawn from experiments and from computed rotational strengths linking amide-I and amide-II patterns in the vibrational circular dichroism (VCD) spectra of peptides with their backbone structures. For peptides with at least three residues (n ≥ 3) these characteristic patterns from coupled amide vibrational modes have robust signatures. For shorter peptide models many vibrational modes are nonrobust, and the robust modes can be dependent on the residues or on their side chain conformations in addition to backbone conformations. These robust VCD bands, however, provide information for the detailed structural analysis of these smaller systems.

  3. Identification of the growth hormone-releasing hormone analogue [Pro1, Val14]-hGHRH with an incomplete C-term amidation in a confiscated product.

    Science.gov (United States)

    Esposito, Simone; Deventer, Koen; Van Eenoo, Peter

    2014-01-01

    In this work, a modified version of the 44 amino acid human growth hormone-releasing hormone (hGHRH(1-44)) containing an N-terminal proline extension, a valine residue in position 14, and a C-terminus amidation (sequence: PYADAIFTNSYRKVVLGQLSARKLLQDIMSRQQGESNQERGARARL-NH2 ) has been identified in a confiscated product by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Investigation of the product suggests also an incomplete C-term amidation. Similarly to other hGHRH analogues, available in black markets, this peptide can potentially be used as performance-enhancing drug due to its growth hormone releasing activity and therefore it should be considered as a prohibited substance in sport. Additionally, the presence of partially amidated molecule reveals the poor pharmaceutical quality of the preparation, an aspect which represents a big concern for public health as well.

  4. Comparison of Substrate Specificity of Escherichia Coli p-Aminobenzoyl-Glutamate Hydrolase with Pseudomonas Carboxypeptidase G

    Science.gov (United States)

    Larimer, Cassandra M.; Slavnic, Dejan; Pitstick, Lenore D.; Green, Jacalyn M.

    2016-01-01

    Reduced folic acid derivatives support biosynthesis of DNA, RNA and amino acids in bacteria as well as in eukaryotes, including humans. While the genes and steps for bacterial folic acid synthesis are known, those associated with folic acid catabolism are not well understood. A folate catabolite found in both humans and bacteria is p-aminobenzoyl-glutamate (PABA-GLU). The enzyme p-aminobenzoyl-glutamate hydrolase (PGH) breaks down PABA-GLU and is part of an apparent operon, the abg region, in E. coli. The subunits of PGH possess sequence and catalytic similarities to carboxypeptidase enzymes from Pseudomonas species. A comparison of the subunit sequences and activity of PGH, relative to carboxypeptidase enzymes, may lead to a better understanding of bacterial physiology and pathway evolution. We first compared the amino acid sequences of AbgA, AbgB and carboxypeptidase G2 from Pseudomonas sp. RS-16, which has been crystallized. Then we compared the enzyme activities of E. coli PGH and commercially available Pseudomonas carboxypeptidase G using spectrophotometric assays measuring cleavage of PABA-GLU, folate, aminopterin, methotrexate, 5-formyltetrahydrofolate, and 5-methyltetrahydrofolate. The Km and Vmax values for the folate and anti-folate substrates of PGH could not be determined, because the instrument reached its limit before the enzyme was saturated. Therefore, activity of PGH was compared to the activity of CPG, or normalized to PABA-GLU (nmole/min/µg). Relative to its activity with 10 µM PABA-GLU (100%), PGH cleaved glutamate from methotrexate (48%), aminopterin (45%) and folate (9%). Reduced folates leucovorin (5-formyltetrahydrofolate) and 5-methyltetrahydrofolate were not cleaved by PGH. Our data suggest that E. coli PGH is specific for PABA-GLU as its activity with natural folates (folate, 5-methyltetrahydrofolate, and leucovorin) was very poor. It does, however, have some ability to cleave anti-folates which may have clinical applications in

  5. Studies on the amide compounds ofMirabilis. Jalapa. L

    Institute of Scientific and Technical Information of China (English)

    SHEN; XuWei

    2001-01-01

    Mirabilis himalaica(Edgew.)Heinerl Var. Chinensis Heimerl belonging to the genus Mirabilis are used in chinese medicine as a remedy for various diseases[1].Its chemical constituents,however, have not been reported so far. we have carried out a detailed chemical investigatigation of the seeds and have isolated two new amides along with three known compounds.  The known compounds were identified by comparing their spectral data with those of authentic samples or with those reported in literature as daucosterol[2], bsitoserol[2], boeravinone E[3], in the present note, the structural elucidation of two new amides is reported.  ……

  6. Study on Alternating Copolymerization of Polyester-amides

    Institute of Scientific and Technical Information of China (English)

    WEI Wen-liang; LI Jian-mei; ZHU Fang-liang

    2002-01-01

    The preparing methods, choice of catalysts and reaction kinetics of one of the monomers, diesteramide(DEA), of polyester-amides were investigated in details. The chemical structure of DEA was analyzed. And the Polyester-amides (PEA) were obtained by melt copolymerization with DEA. It is shown that DEA can be synthesized by DMT and hexamethylene diamine with the catalyst EX - 1 or EX - 2. The relationship between reaction rate of synthesizing monomer and concentration of hexamethylene diamine is first order kinetic relation.

  7. Studies on the amide compounds ofMirabilis. Jalapa. L

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Mirabilis himalaica(Edgew.)Heinerl Var. Chinensis Heimerl belonging to the genus Mirabilis are used in chinese medicine as a remedy for various diseases[1].Its chemical constituents,however, have not been reported so far. we have carried out a detailed chemical investigatigation of the seeds and have isolated two new amides along with three known compounds. The known compounds were identified by comparing their spectral data with those of authentic samples or with those reported in literature as daucosterol[2], bsitoserol[2], boeravinone E[3], in the present note, the structural elucidation of two new amides is reported.

  8. Synthon preferences in cocrystals of cis-carboxamides:carboxylic acids

    NARCIS (Netherlands)

    Moragues-Bartolome, A.M.; Jones, W.; Cruz-Cabeza, A.J.

    2012-01-01

    We study synthon preferences in cocrystals of cis-carboxamides with carboxylic acids using a combination of database analyses, cocrystallisation experiments and theoretical calculations. We classify the cis-carboxamides into three families: primary amides, cyclic amides (lactams) and cyclic imides.

  9. Discovery of 1-(1,3,5-triazin-2-yl)piperidine-4-carboxamides as inhibitors of soluble epoxide hydrolase.

    Science.gov (United States)

    Thalji, Reema K; McAtee, Jeff J; Belyanskaya, Svetlana; Brandt, Martin; Brown, Gregory D; Costell, Melissa H; Ding, Yun; Dodson, Jason W; Eisennagel, Steve H; Fries, Rusty E; Gross, Jeffrey W; Harpel, Mark R; Holt, Dennis A; Israel, David I; Jolivette, Larry J; Krosky, Daniel; Li, Hu; Lu, Quinn; Mandichak, Tracy; Roethke, Theresa; Schnackenberg, Christine G; Schwartz, Benjamin; Shewchuk, Lisa M; Xie, Wensheng; Behm, David J; Douglas, Stephen A; Shaw, Ami L; Marino, Joseph P

    2013-06-15

    1-(1,3,5-Triazin-yl)piperidine-4-carboxamide inhibitors of soluble epoxide hydrolase were identified from high through-put screening using encoded library technology. The triazine heterocycle proved to be a critical functional group, essential for high potency and P450 selectivity. Phenyl group substitution was important for reducing clearance, and establishing good oral exposure. Based on this lead optimization work, 1-[4-methyl-6-(methylamino)-1,3,5-triazin-2-yl]-N-{[[4-bromo-2-(trifluoromethoxy)]-phenyl]methyl}-4-piperidinecarboxamide (27) was identified as a useful tool compound for in vivo investigation. Robust effects on a serum biomarker, 9, 10-epoxyoctadec-12(Z)-enoic acid (the epoxide derived from linoleic acid) were observed, which provided evidence of robust in vivo target engagement and the suitability of 27 as a tool compound for study in various disease models.

  10. The Structural Basis of Exopolygalacturonase Activity in a Family 28 Glycoside Hydrolase

    Energy Technology Data Exchange (ETDEWEB)

    Abbott,D.; Boraston, A.

    2007-01-01

    Family 28 glycoside hydrolases (polygalacturonases) are found in organisms across the plant, fungal and bacterial kingdoms, where they are central to diverse biological functions such as fruit ripening, biomass recycling and plant pathogenesis. The structures of several polygalacturonases have been reported; however, all of these enzymes utilize an endo-mode of digestion, which generates a spectrum of oligosaccharide products with varying degrees of polymerization. The structure of a complementary exo-acting polygalacturonase and an accompanying explanation of the molecular determinants for its specialized activity have been noticeably lacking. We present the structure of an exopolygalacturonase from Yersinia enterocolitica, YeGH28 in a native form (solved to 2.19 {angstrom} resolution) and a digalacturonic acid product complex (solved to 2.10 {angstrom} resolution). The activity of YeGH28 is due to inserted stretches of amino acid residues that transform the active site from the open-ended channel observed in the endopolygalacturonases to a closed pocket that restricts the enzyme to the exclusive attack of the non-reducing end of oligogalacturonide substrates. In addition, YeGH28 possesses a fused FN3 domain with unknown function, the first such structure described in pectin active enzymes.

  11. Purification and Characterization of Conjugated Bile Salt Hydrolase from Bifidobacterium longum BB536.

    Science.gov (United States)

    Grill, J; Schneider, F; Crociani, J; Ballongue, J

    1995-07-01

    Bifidobacterium species deconjugate taurocholic, taurodeoxycholic, taurochenodeoxycholic, glycocholic, glycodeoxycholic, and glycochenodeoxycholic acids. The enzyme level increases in the growth phase. No increase in activity is observed for the cytoplasmic enzyme after addition of conjugated bile acids to a stationary-phase culture. Conjugated bile salt hydrolase (BSH) was purified from Bifidobacterium longum BB536. Its apparent molecular mass in denaturing polyacrylamide gel electrophoresis was ca. 40,000 Da. The intact enzyme had a relative molecular weight of ca. 250,000 as determined by gel filtration chromatography, suggesting that the native BSH of B. longum is probably a hexamer. The purified enzyme is active towards both glycine and taurine conjugates of cholate, deoxycholate, and chenodeoxycholate. The pH optimum is in the range of 5.5 to 6.5. A loss of BSH activity is observed after incubation at temperatures higher than 42(deg)C; at 60(deg)C, 50% of the BSH activity is lost. The importance of free sulfhydryl groups at the enzyme active center is suggested. For B. longum BB536, no significant difference in the initial rate of deconjugation and enzymatic efficiency appears between bile salts. The enzymatic efficiency is higher for B. longum BB536 than for other genera. In this paper, a new method which permits a display of BSH activity directly on polyacrylamide gels is described; this method confirms the molecular weight obtained for B. longum BB536 BSH.

  12. Cloning and Expression of Bile Salt Hydrolase Gene from Lactobacillus plantarum M1-UVS29

    Institute of Scientific and Technical Information of China (English)

    Yu Chang-qing; Li Rong

    2015-01-01

    We cloned and expressed bile salt hydrolase gene ofLactobacillus plantarum M1-UVS29 inLactococcus lactis NZ9000 successfully. Gene-specific primers for amplification ofL. plantarum bsh were designed by using sequence which availabled from GenBank. The production of PCR amplicon was confirmed by sequencing and cloned into pMD18-T vector, and then recombined into expression vector pNZ8148 and yielding vector pNZ8148-BSH. pNZ8148-BSH was transferred intoLactococcus lactis NZ9000. Sequencing indicated that the clonedbsh fragment contained 995 nucleotides, and shared 99.3% sequence homology withbsh gene fromL. plantarum MBUL10. Clonedbsh fragment was successfully transduced into NICE expression system and confirmed by PCR and restriction digest. Recombinant BSH protein was analyzed by SDS-PAGE. The molecular weight of BSH protein was approximately 37 ku. Activity of the expressed protein was 0.77 µmol• min-1. The successfully expressed proteins by genetic engineering technology made the function of lactic acid bacteria be abundant and laid the foundation for further researches into cholesterol-lowering lactic acid bacterium food and probiotics.

  13. EHPred: an SVM-based method for epoxide hydrolases recognition and classification

    Institute of Scientific and Technical Information of China (English)

    JIA Jia; YANG Liang; ZHANG Zi-zhang

    2006-01-01

    A two-layer method based on support vector machines (SVMs) has been developed to distinguish epoxide hydrolases (EHs) from other enzymes and to classify its subfamilies using its primary protein sequences. SVM classifiers were built using three different feature vectors extracted from the primary sequence of EHs: the amino acid composition (AAC), the dipeptide composition (DPC), and the pseudo-amino acid composition (PAAC). Validated by 5-fold cross tests, the first layer SVM classifier can differentiate EHs and non-EHs with an accuracy of 94.2% and has a Matthew,s correlation coefficient (MCC) of 0.84.Using 2-fold cross validation, PAAC-based second layer SVM can further classify EH subfamilies with an overall accuracy of 90.7% and MCC of 0.87 as compared to AAC (80.0%) and DPC (84.9%). A program called EHPred has also been developed to assist readers to recognize EHs and to classify their subfamilies using primary protein sequences with greater accuracy.

  14. New insights into plant glycoside hydrolase family 32 in Agave species.

    Science.gov (United States)

    Avila de Dios, Emmanuel; Gomez Vargas, Alan D; Damián Santos, Maura L; Simpson, June

    2015-01-01

    In order to optimize the use of agaves for commercial applications, an understanding of fructan metabolism in these species at the molecular and genetic level is essential. Based on transcriptome data, this report describes the identification and molecular characterization of cDNAs and deduced amino acid sequences for genes encoding fructosyltransferases, invertases and fructan exohydrolases (FEH) (enzymes belonging to plant glycoside hydrolase family 32) from four different agave species (A. tequilana, A. deserti, A. victoriae-reginae, and A. striata). Conserved amino acid sequences and a hypervariable domain allowed classification of distinct isoforms for each enzyme type. Notably however neither 1-FFT nor 6-SFT encoding cDNAs were identified. In silico analysis revealed that distinct isoforms for certain enzymes found in a single species, showed different levels and tissue specific patterns of expression whereas in other cases expression patterns were conserved both within the species and between different species. Relatively high levels of in silico expression for specific isoforms of both invertases and fructosyltransferases were observed in floral tissues in comparison to vegetative tissues such as leaves and stems and this pattern was confirmed by Quantitative Real Time PCR using RNA obtained from floral and leaf tissue of A. tequilana. Thin layer chromatography confirmed the presence of fructans with degree of polymerization (DP) greater than DP three in both immature buds and fully opened flowers also obtained from A. tequilana.

  15. New insights into plant glycoside hydrolase family 32 in Agave species

    Directory of Open Access Journals (Sweden)

    Emmanuel eAvila-de Dios

    2015-08-01

    Full Text Available In order to optimize the use of agaves for commercial applications, an understanding of fructan metabolism in these species at the molecular and genetic level is essential. Based on transcriptome data, this report describes the identification and molecular characterization of cDNAs and deduced amino acid sequences for genes encoding fructosyltransferases, invertases and fructan exohydrolases (enzymes belonging to plant glycoside hydrolase family 32 from four different agave species (A. tequilana, A. deserti, A. victoriae-reginae and A. striata. Conserved amino acid sequences and a hypervariable domain allowed classification of distinct isoforms for each enzyme type. Notably however neither 1-FFT nor 6-SFT encoding cDNAs were identified. In silico analysis revealed that distinct isoforms for certain enzymes found in a single species, showed different levels and tissue specific patterns of expression whereas in other cases expression patterns were conserved both within the species and between different species. Relatively high levels of in silico expression for specific isoforms of both invertases and fructosyltransferases were observed in floral tissues in comparison to vegetative tissues such as leaves and stems and this pattern was confirmed by Quantitative Real Time PCR using RNA obtained from floral and leaf tissue of A. tequilana. Thin layer chromatography confirmed the presence of fructans with degree of polymerization (DP greater than DP three in both immature buds and fully opened flowers also obtained from A. tequilana.

  16. Structural Analysis of a Family 101 Glycoside Hydrolase in Complex with Carbohydrates Reveals Insights into Its Mechanism.

    Science.gov (United States)

    Gregg, Katie J; Suits, Michael D L; Deng, Lehua; Vocadlo, David J; Boraston, Alisdair B

    2015-10-16

    O-Linked glycosylation is one of the most abundant post-translational modifications of proteins. Within the secretory pathway of higher eukaryotes, the core of these glycans is frequently an N-acetylgalactosamine residue that is α-linked to serine or threonine residues. Glycoside hydrolases in family 101 are presently the only known enzymes to be able to hydrolyze this glycosidic linkage. Here we determine the high-resolution structures of the catalytic domain comprising a fragment of GH101 from Streptococcus pneumoniae TIGR4, SpGH101, in the absence of carbohydrate, and in complex with reaction products, inhibitor, and substrate analogues. Upon substrate binding, a tryptophan lid (residues 724-WNW-726) closes on the substrate. The closing of this lid fully engages the substrate in the active site with Asp-764 positioned directly beneath C1 of the sugar residue bound within the -1 subsite, consistent with its proposed role as the catalytic nucleophile. In all of the bound forms of the enzyme, however, the proposed catalytic acid/base residue was found to be too distant from the glycosidic oxygen (>4.3 Å) to serve directly as a general catalytic acid/base residue and thereby facilitate cleavage of the glycosidic bond. These same complexes, however, revealed a structurally conserved water molecule positioned between the catalytic acid/base and the glycosidic oxygen. On the basis of these structural observations we propose a new variation of the retaining glycoside hydrolase mechanism wherein the intervening water molecule enables a Grotthuss proton shuttle between Glu-796 and the glycosidic oxygen, permitting this residue to serve as the general acid/base catalytic residue.

  17. Optimized Reaction Conditions for Amide Bond Formation in DNA-Encoded Combinatorial Libraries.

    Science.gov (United States)

    Li, Yizhou; Gabriele, Elena; Samain, Florent; Favalli, Nicholas; Sladojevich, Filippo; Scheuermann, Jörg; Neri, Dario

    2016-08-08

    DNA-encoded combinatorial libraries are increasingly being used as tools for the discovery of small organic binding molecules to proteins of biological or pharmaceutical interest. In the majority of cases, synthetic procedures for the formation of DNA-encoded combinatorial libraries incorporate at least one step of amide bond formation between amino-modified DNA and a carboxylic acid. We investigated reaction conditions and established a methodology by using 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide, 1-hydroxy-7-azabenzotriazole and N,N'-diisopropylethylamine (EDC/HOAt/DIPEA) in combination, which provided conversions greater than 75% for 423/543 (78%) of the carboxylic acids tested. These reaction conditions were efficient with a variety of primary and secondary amines, as well as with various types of amino-modified oligonucleotides. The reaction conditions, which also worked efficiently over a broad range of DNA concentrations and reaction scales, should facilitate the synthesis of novel DNA-encoded combinatorial libraries.

  18. In silico modeling of the molecular structure and binding of leukotriene A4 into leukotriene A4 hydrolase

    CERN Document Server

    Paz, Paula B; Estrada, Mario R; Martinez, Juan C Garro

    2012-01-01

    A combined molecular docking and molecular structure in silico analysis on the substrate and product of leukotriene A4 hydrolase (LTA4H) was performed. The molecular structures of the substrate leukotriene A4 (LTA4) and product leukotirene B4 (LTB4) were studied through Density Functional Theory (DFT) calculations at the B3LYP/6-31+G(d) level of theory in both, gas and condensed phases. The whole LTB4 molecule was divided into three fragments (hydrophobic tail, triene motif, and a polar acidic group) which were subjected to a full conformational study employing the most stable conformations of them to build conformers of the complete molecule and geometry optimize further. LTA4 conformers structures were modeled from the LTB4 minimum energy conformers. Both, protonated and deprotonated species of LTA4 and LTB4, were analyzed according to pKa values founded in the literature. Finally, a binding model of LTA4 with LTA4 hydrolase is proposed according to docking results which show intermolecular interactions tha...

  19. Cholesteryl ester hydrolase activity is abolished in HSL-/- macrophages but unchanged in macrophages lacking KIAA1363.

    Science.gov (United States)

    Buchebner, Marlene; Pfeifer, Thomas; Rathke, Nora; Chandak, Prakash G; Lass, Achim; Schreiber, Renate; Kratzer, Adelheid; Zimmermann, Robert; Sattler, Wolfgang; Koefeler, Harald; Fröhlich, Eleonore; Kostner, Gerhard M; Birner-Gruenberger, Ruth; Chiang, Kyle P; Haemmerle, Guenter; Zechner, Rudolf; Levak-Frank, Sanja; Cravatt, Benjamin; Kratky, Dagmar

    2010-10-01

    Cholesteryl ester (CE) accumulation in macrophages represents a crucial event during foam cell formation, a hallmark of atherogenesis. Here we investigated the role of two previously described CE hydrolases, hormone-sensitive lipase (HSL) and KIAA1363, in macrophage CE hydrolysis. HSL and KIAA1363 exhibited marked differences in their abilities to hydrolyze CE, triacylglycerol (TG), diacylglycerol (DG), and 2-acetyl monoalkylglycerol ether (AcMAGE), a precursor for biosynthesis of platelet-activating factor (PAF). HSL efficiently cleaved all four substrates, whereas KIAA1363 hydrolyzed only AcMAGE. This contradicts previous studies suggesting that KIAA1363 is a neutral CE hydrolase. Macrophages of KIAA1363(-/-) and wild-type mice exhibited identical neutral CE hydrolase activity, which was almost abolished in tissues and macrophages of HSL(-/-) mice. Conversely, AcMAGE hydrolase activity was diminished in macrophages and some tissues of KIAA1363(-/-) but unchanged in HSL(-/-) mice. CE turnover was unaffected in macrophages lacking KIAA1363 and HSL, whereas cAMP-dependent cholesterol efflux was influenced by HSL but not by KIAA1363. Despite decreased CE hydrolase activities, HSL(-/-) macrophages exhibited CE accumulation similar to wild-type (WT) macrophages. We conclude that additional enzymes must exist that cooperate with HSL to regulate CE levels in macrophages. KIAA1363 affects AcMAGE hydrolase activity but is of minor importance as a direct CE hydrolase in macrophages.

  20. Leishmania donovani Nucleoside Hydrolase Terminal Domains in Cross-Protective Immunotherapy Against Leishmania amazonensis Murine Infection

    Science.gov (United States)

    Nico, Dirlei; Gomes, Daniele Crespo; Palatnik-de-Sousa, Iam; Morrot, Alexandre; Palatnik, Marcos; Palatnik-de-Sousa, Clarisa Beatriz

    2014-01-01

    Nucleoside hydrolases of the Leishmania genus are vital enzymes for the replication of the DNA and conserved phylogenetic markers of the parasites. Leishmania donovani nucleoside hydrolase (NH36) induced a main CD4+ T cell driven protective response against L. chagasi infection in mice which is directed against its C-terminal domain. In this study, we used the three recombinant domains of NH36: N-terminal domain (F1, amino acids 1–103), central domain (F2 aminoacids 104–198), and C-terminal domain (F3 amino acids 199–314) in combination with saponin and assayed their immunotherapeutic effect on Balb/c mice previously infected with L. amazonensis. We identified that the F1 and F3 peptides determined strong cross-immunotherapeutic effects, reducing the size of footpad lesions to 48 and 64%, and the parasite load in footpads to 82.6 and 81%, respectively. The F3 peptide induced the strongest anti-NH36 antibody response and intradermal response (IDR) against L. amazonenis and a high secretion of IFN-γ and TNF-α with reduced levels of IL-10. The F1 vaccine, induced similar increases of IgG2b antibodies and IFN-γ and TNF-α levels, but no IDR and no reduction of IL-10. The multiparameter flow cytometry analysis was used to assess the immune response after immunotherapy and disclosed that the degree of the immunotherapeutic effect is predicted by the frequencies of the CD4+ and CD8+ T cells producing IL-2 or TNF-α or both. Total frequencies and frequencies of double-cytokine CD4 T cell producers were enhanced by F1 and F3 vaccines. Collectively, our multifunctional analysis disclosed that immunotherapeutic protection improved as the CD4 responses progressed from 1+ to 2+, in the case of the F1 and F3 vaccines, and as the CD8 responses changed qualitatively from 1+ to 3+, mainly in the case of the F1 vaccine, providing new correlates of immunotherapeutic protection against cutaneous leishmaniasis in mice based on T-helper TH1 and CD8+ mediated immune responses

  1. Genetic enhancement of microsomal epoxide hydrolase improves metabolic detoxification but impairs cerebral blood flow regulation.

    Science.gov (United States)

    Marowsky, Anne; Haenel, Karen; Bockamp, Ernesto; Heck, Rosario; Rutishauser, Sibylle; Mule, Nandkishor; Kindler, Diana; Rudin, Markus; Arand, Michael

    2016-12-01

    Microsomal epoxide hydrolase (mEH) is a detoxifying enzyme for xenobiotic compounds. Enzymatic activity of mEH can be greatly increased by a point mutation, leading to an E404D amino acid exchange in its catalytic triad. Surprisingly, this variant is not found in any vertebrate species, despite the obvious advantage of accelerated detoxification. We hypothesized that this evolutionary avoidance is due to the fact that the mEH plays a dualistic role in detoxification and control of endogenous vascular signaling molecules. To test this, we generated mEH E404D mice and assessed them for detoxification capacity and vascular dynamics. In liver microsomes from these mice, turnover of the xenobiotic compound phenanthrene-9,10-oxide was four times faster compared to WT liver microsomes, confirming accelerated detoxification. mEH E404D animals also showed faster metabolization of a specific class of endogenous eicosanoids, arachidonic acid-derived epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs). Significantly higher DHETs/EETs ratios were found in mEH E404D liver, urine, plasma, brain and cerebral endothelial cells compared to WT controls, suggesting a broad impact of the mEH mutant on endogenous EETs metabolism. Because EETs are strong vasodilators in cerebral vasculature, hemodynamics were assessed in mEH E404D and WT cerebral cortex and hippocampus using cerebral blood volume (CBV)-based functional magnetic resonance imaging (fMRI). Basal CBV0 levels were similar between mEH E404D and control mice in both brain areas. But vascular reactivity and vasodilation in response to the vasodilatory drug acetazolamide were reduced in mEH E404D forebrain compared to WT controls by factor 3 and 2.6, respectively. These results demonstrate a critical role for mEH E404D in vasodynamics and suggest that deregulation of endogenous signaling pathways is the undesirable gain of function associated with the E404D variant.

  2. α/β-hydrolase domain containing protein 15 (ABHD15--an adipogenic protein protecting from apoptosis.

    Directory of Open Access Journals (Sweden)

    Evelyn Walenta

    Full Text Available Our knowledge about adipocyte metabolism and development is steadily growing, yet many players are still undefined. Here, we show that α/β-hydrolase domain containing protein 15 (Abhd15 is a direct and functional target gene of peroxisome proliferator-activated receptor gamma (PPARγ, the master regulator of adipogenesis. In line, Abhd15 is mainly expressed in brown and white adipose tissue and strongly upregulated during adipogenesis in various murine and human cell lines. Stable knockdown of Abhd15 in 3T3-L1 cells evokes a striking differentiation defect, as evidenced by low lipid accumulation and decreased expression of adipocyte marker genes. In preconfluent cells, knockdown of Abhd15 leads to impaired proliferation, which is caused by apoptosis, as we see an increased SubG1 peak, caspase 3/7 activity, and BAX protein expression as well as a reduction in anti-apoptotic BCL-2 protein. Furthermore, apoptosis-inducing amounts of palmitic acid evoke a massive increase of Abhd15 expression, proposing an apoptosis-protecting role for ABHD15. On the other hand, in mature adipocytes physiological (i.e. non-apoptotic concentrations of palmitic acid down-regulate Abhd15 expression. Accordingly, we found that the expression of Abhd15 in adipose tissue is reduced in physiological situations with high free fatty acid levels, like high-fat diet, fasting, and aging as well as in genetically obese mice. Collectively, our results position ABHD15 as an essential component in the development of adipocytes as well as in apoptosis, thereby connecting two substantial factors in the regulation of adipocyte number and size. Together with its intricate regulation by free fatty acids, ABHD15 might be an intriguing new target in obesity and diabetes research.

  3. Molecular cloning, characterization and heterologous expression of bile salt hydrolase (Bsh) from Lactobacillus fermentum NCDO394.

    Science.gov (United States)

    Kumar, Rajesh; Rajkumar, Hemalatha; Kumar, Manoj; Varikuti, Sudarshan Reddy; Athimamula, Ramakrishna; Shujauddin, Mohd; Ramagoni, Ramesh; Kondapalli, Narendrababu

    2013-08-01

    Bile salt hydrolase (Bsh) active probiotic strains hydrolyze bile acid amino conjugates in vivo, which triggers cholesterol consumption in liver to synthesize new bile leading to consequential cholesterol lowering. Hence, bile salt hydrolyzing potential was the criterion to select L. fermentum NCDO394 for this study and its gene encoding Bsh was identified and cloned. The resulting nucleotide sequence of bsh gene contained an open reading frame (ORF) of 978 nucleotides encoding a predicted protein of 325 amino acids with a theoretical pI of 6.39. Moreover, deduced Bsh protein had high similarity with the Bshs of L. fermentum only and also exhibited significant similarity to the Pencillin V amidases of other Lactobacillus spp. Five catalytically important amino acids were highly conserved in L. fermentum Bsh while four amino acid motifs around these active sites, were not as consistent as in other Bsh proteins. Furthermore, L. fermentum bsh gene was sub-cloned into pET-28b(+) vector, and its expression was induced with 0.05 mM isopropylthiogalactopyranoside (IPTG) in Escherichia coli BL21(DE3). The recombinant Bsh (rBsh) was purified with homogeneity using Ni+2-NTA column and characterized for substrate specificity, pH and temperature. The rBsh hydrolyzed six major human bile salts with a slight preference towards glycine-conjugated bile salts. The optimum pH of rBsh was six, and its enzymatic activity declined below pH 5 and above pH 7. The enzyme was stable and functional even at 65 °C while showed its maximum activity at 37 °C. In conclusion, L. fermentum NCDO394 may be a promising candidate probiotic which may affect cholesterol metabolism in vivo.

  4. Soluble epoxide hydrolase activity determines the severity of ischemia-reperfusion injury in kidney.

    Directory of Open Access Journals (Sweden)

    Jung Pyo Lee

    Full Text Available Soluble epoxide hydrolase (sEH in endothelial cells determines the plasma concentrations of epoxyeicosatrienoic acids (EETs, which may act as vasoactive agents to control vascular tone. We hypothesized that the regulation of sEH activity may have a therapeutic value in preventing acute kidney injury by controlling the concentration of EETs. In this study, we therefore induced ischemia-reperfusion injury (IRI in C57BL/6 mice and controlled sEH activity by intraperitoneal administration of the sEH inhibitor 12-(3-adamantan-1-ylureido-dodecanoic acid (AUDA. The deterioration of kidney function induced by IRI was partially moderated and prevented by AUDA treatment. In addition, AUDA treatment significantly attenuated tubular necrosis induced by IRI. Ischemic injury induced the down-regulation of sEH, and AUDA administration had no effect on the expression pattern of sEH induced by IRI. In vivo sEH activity was assessed by measuring the substrate epoxyoctadecenoic acid (EpOME and its metabolite dihydroxyoctadec-12-enoic acid (DHOME. Ischemic injury had no effects on the plasma concentrations of EpOME and DHOME, but inhibition of sEH by AUDA significantly increased plasma EpOME and the EpOME/DHOME ratio. The protective effect of the sEH inhibitor was achieved by suppression of proinflammatory cytokines and up-regulation of regulatory cytokines. AUDA treatment prevented the intrarenal infiltration of inflammatory cells, but promoted endothelial cell migration and neovascularization. The results of this study suggest that treatment with sEH inhibitors can reduce acute kidney injury.

  5. Use of triphenyl phosphate as risk mitigant for metal amide hydrogen storage materials

    Energy Technology Data Exchange (ETDEWEB)

    Cortes-Concepcion, Jose A.; Anton, Donald L.

    2016-04-26

    A process in a resulting product of the process in which a hydrogen storage metal amide is modified by a ball milling process using an additive of TPP. The resulting product provides for a hydrogen storage metal amide having a coating that renders the hydrogen storage metal amide resistant to air, ambient moisture, and liquid water while improving useful hydrogen storage and release kinetics.

  6. FMRF-amide-like immunoreactivity in brain and pituitary of the hagfish Eptatretus burgeri (Cyclostomata)

    DEFF Research Database (Denmark)

    Jirikowski, G; Erhart, G; Grimmelikhuijzen, C J

    1984-01-01

    the hypothalamus to the olfactory system and caudally to the medulla oblongata. FMRF-amide-like immunoreactivity was also found in cells of the adenohypophysis. These observations suggest that the hagfish possesses a brain FMRF-amide-like transmitter system and pituitary cells containing FMRF-amide-like material...

  7. 40 CFR 721.10176 - Amides, peanut-oil, N-[3-(dimethylamino)propyl].

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amides, peanut-oil, N- . 721.10176... Substances § 721.10176 Amides, peanut-oil, N- . (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as amides, peanut-oil, N- (PMN P-04-144; CAS No....

  8. 40 CFR 721.9075 - Quaternary ammonium salt of fluorinated alkylaryl amide.

    Science.gov (United States)

    2010-07-01

    ... fluorinated alkylaryl amide. 721.9075 Section 721.9075 Protection of Environment ENVIRONMENTAL PROTECTION... amide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as quaternary ammonium salt of fluorinated alkylaryl amide (PMN No. P-92-688)...

  9. 40 CFR 721.10063 - Halo substituted hydroxy nitrophenyl amide (generic).

    Science.gov (United States)

    2010-07-01

    ... amide (generic). 721.10063 Section 721.10063 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10063 Halo substituted hydroxy nitrophenyl amide (generic). (a) Chemical... as halo substituted hydroxy nitrophenyl amide (PMN P-04-792) is subject to reporting under...

  10. 40 CFR 721.10191 - Amides, coco, N-[3-(dibutylamino)propyl].

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amides, coco, N- . 721.10191 Section... Substances § 721.10191 Amides, coco, N- . (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as amides, coco, N- (PMN P-06-262; CAS No. 851544-20-2)...

  11. 40 CFR 721.10192 - Amides, coco, N-[3-(dibutylamino)propyl], acrylates.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amides, coco, N- , acrylates. 721... Substances § 721.10192 Amides, coco, N- , acrylates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as amides, coco, N- , acrylates (PMN...

  12. Polyurethane elastomers with amide chain extenders of uniform length

    NARCIS (Netherlands)

    Schuur, van der Martijn; Noordover, Bart; Gaymans, Reinoud J.

    2006-01-01

    Toluene diisocyanate based polyurethanes with amide extenders were synthesized poly(propylene oxide) with a number average molecular weight of 2000 and endcapped with toluene diisocyanate was used as the polyether segment. The chain extenders were based on poly(hexamethylene terephthalamide): hexame

  13. Modeling the amide I bands of small peptides

    NARCIS (Netherlands)

    Jansen, Thomas la Cour; Dijkstra, Arend G.; Watson, Tim M.; Hirst, Jonathan D.; Knoester, Jasper

    2006-01-01

    In this paper different floating oscillator models for describing the amide I band of peptides and proteins are compared with density functional theory (DFT) calculations. Models for the variation of the frequency shifts of the oscillators and the nearest-neighbor coupling between them with respect

  14. KNH2-KH: a metal amide-hydride solid solution.

    Science.gov (United States)

    Santoru, Antonio; Pistidda, Claudio; Sørby, Magnus H; Chierotti, Michele R; Garroni, Sebastiano; Pinatel, Eugenio; Karimi, Fahim; Cao, Hujun; Bergemann, Nils; Le, Thi T; Puszkiel, Julián; Gobetto, Roberto; Baricco, Marcello; Hauback, Bjørn C; Klassen, Thomas; Dornheim, Martin

    2016-09-27

    We report for the first time the formation of a metal amide-hydride solid solution. The dissolution of KH into KNH2 leads to an anionic substitution, which decreases the interaction among NH2(-) ions. The rotational properties of the high temperature polymorphs of KNH2 are thereby retained down to room temperature.

  15. Thermodynamics of Enzyme-Catalyzed Reactions. Part 3. Hydrolases

    Science.gov (United States)

    Goldberg, Robert N.; Tewari, Yadu B.

    1994-11-01

    Equilibrium constants and enthalpy changes for reactions catalyzed by the hydrolase class of enzymes have been compiled. For each reaction the following information is given: The reference for the data; the reaction studied; the name of the enzyme used and its Enzyme Commission number; the method of measurement; the conditions of measurement [temperature, pH, ionic strength, and the buffer(s) and cofactor(s) used]; the data and an evaluation of it; and, sometimes, commentary on the data and on any corrections which have been applied to it or any calculations for which the data have been used. The data from 145 references have been examined and evaluated. Chemical Abstract Service registry numbers are given for the substances involved in these various reactions. There is a cross reference between the substances and the Enzyme Commission numbers of the enzymes used to catalyze the reactions in which the substances participate.

  16. Insecticidal, repellent and fungicidal properties of novel trifluoromethylphenyl amides.

    Science.gov (United States)

    Tsikolia, Maia; Bernier, Ulrich R; Coy, Monique R; Chalaire, Katelyn C; Becnel, James J; Agramonte, Natasha M; Tabanca, Nurhayat; Wedge, David E; Clark, Gary G; Linthicum, Kenneth J; Swale, Daniel R; Bloomquist, Jeffrey R

    2013-09-01

    Twenty trifluoromethylphenyl amides were synthesized and evaluated as fungicides and as mosquito toxicants and repellents. Against Aedes aegypti larvae, N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-3,5-dinitrobenzamide (1e) was the most toxic compound (24 h LC50 1940 nM), while against adults N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-2,2,2-trifluoroacetamide (1c) was most active (24 h LD50 19.182 nM, 0.5 μL/insect). However, the 24 h LC50 and LD50 values of fipronil against Ae. aegypti larvae and adults were significantly lower: 13.55 nM and 0.787 × 10(-4) nM, respectively. Compound 1c was also active against Drosophila melanogaster adults with 24 h LC50 values of 5.6 and 4.9 μg/cm(2) for the Oregon-R and 1675 strains, respectively. Fipronil had LC50 values of 0.004 and 0.017 μg/cm(2) against the two strains of D. melanogaster, respectively. In repellency bioassays against female Ae. aegypti, 2,2,2-trifluoro-N-(2-(trifluoromethyl)phenyl)acetamide (4c) had the highest repellent potency with a minimum effective dosage (MED) of 0.039 μmol/cm(2) compared to DEET (MED of 0.091 μmol/cm(2)). Compound N-(2-(trifluoromethyl)phenyl)hexanamide (4a) had an MED of 0.091 μmol/cm(2) which was comparable to DEET. Compound 4c was the most potent fungicide against Phomopsis obscurans. Several trends were discerned between the structural configuration of these molecules and the effect of structural changes on toxicity and repellency. Para- or meta- trifluoromethylphenyl amides with an aromatic ring attached to the carbonyl carbon showed higher toxicity against Ae. aegypti larvae, than ortho- trifluoromethylphenyl amides. Ortho- trifluoromethylphenyl amides with trifluoromethyl or alkyl group attached to the carbonyl carbon produced higher repellent activity against female Ae. aegypti and Anopheles albimanus than meta- or para- trifluoromethylphenyl amides. The presence of 2,6-dichloro- substitution on the phenyl ring of the amide had an influence on larvicidal and repellent

  17. A specific acid [alpha]-glucosidase in lamellar bodies of the human lung

    OpenAIRE

    Vries, A.C.J. de; Schram, A.W.; Tager, J.M.; Batenburg, J.J.

    2006-01-01

    In the present investigation, we have demonstrated that three lysosomal-type hydrolases, alpha-glucosidase, alpha-mannosidase and a phosphatase, are present in lamellar bodies isolated from adult human lung. The hydrolase activities that were studied, all showed an acidic pH optimum, which is characteristic for lysosomal enzymes. The properties of acid alpha-glucosidase in the lamellar body fraction and that in the lysosome-enriched fraction were compared. Using specific antibodies against ly...

  18. A proposed role for the cuticular fatty amides of Liposcelis bostrychophila (Psocoptera: Liposcelidae) in preventing adhesion of entomopathogenic fungi with dry-conidia.

    Science.gov (United States)

    Lord, Jeffrey C; Howard, Ralph W

    2004-08-01

    Maximum challenge exposure of Liposcelis bostrychophila to Beauveria bassiana, Paecilomyces fumosoroseus, Aspergillus parasiticus or Metarhizium anisopliae resulted in no more than 16% mortality. We investigated several of L. bostrychophila's cuticular lipids for possible contributions to its tolerance for entomopathogenic fungi. Saturated C14 and C16 fatty acids did not reduce the germination rates of B. bassiana or M. anisopliae conidia. Saturated C6 to C12 fatty acids that have not been identified in L. bostrychophila cuticular extracts significantly reduced germination, but the reduction was mitigated by the presence of stearamide. Cis-6-hexadecenal did not affect germination rates. Mycelial growth of either fungal species did not occur in the presence of caprylic acid, was reduced by the presence of lauric acid, and was not significantly affected by palmitic acid. Liposcelis bostrychophila is the only insect for which fatty acid amides have been identified as cuticular components. Stearamide, its major fatty amide, did not reduce germination of B. bassiana or M. anisopliae conidia or growth of their mycelia. Adhesion of conidia to stearamide preparations did not differ significantly from adhesion to the cuticle of L. bostrychophila. Pretreatment of a beetle known to be fungus-susceptible, larval Oryzaephilus surinamensis, with stearamide significantly decreased adhesion of B. bassiana or M. anisopliae conidia to their cuticles. This evidence indicates that cuticular fatty amides may contribute to L. bostrychophila's tolerance for entomopathogenic fungi by decreasing hydrophobicity and static charge, thereby reducing conidial adhesion.

  19. Synthesis, structure, and reactivity of tris(amidate) mono(amido) and tetrakis(amidate) complexes of group 4 transition metals.

    Science.gov (United States)

    Payne, Philippa R; Thomson, Robert K; Medeiros, Diane M; Wan, Geoff; Schafer, Laurel L

    2013-11-28

    The syntheses of a series of tris(amidate) mono(amido) titanium and zirconium complexes are reported. The binding motif of the amidate ligand has been determined to depend on the size of the metal centre for these sterically demanding N,O-chelating ligands; the larger zirconium metal centre supports three κ(2)-(N,O) bound amidate ligands while the titanium analogue has one ligand bound in a κ(1)-(O) fashion to alleviate steric strain. Reactivity studies indicate that, despite high steric crowding about the tris(amidate) mono(amido) zirconium metal centre, transamination of the reactive dimethylamido ligand can be achieved using aniline. This complex is also an active precatalyst for intramolecular alkene hydroamination, in which protonolysis of one amidate ligand in the presence of excess amine is observed as an initiation step prior to catalytic turnover. Eight-coordinate homoleptic κ(2)-amidate complexes of zirconium and hafnium have also been prepared.

  20. Discovery of competing anaerobic and aerobic pathways in umpolung amide synthesis allows for site-selective amide 18O-labeling.

    Science.gov (United States)

    Shackleford, Jessica P; Shen, Bo; Johnston, Jeffrey N

    2012-01-03

    The mechanism of umpolung amide synthesis was probed by interrogating potential sources for the oxygen of the product amide carbonyl that emanates from the α-bromo nitroalkane substrate. Using a series of (18)O-labeled substrates and reagents, evidence is gathered to advance two pathways from the putative tetrahedral intermediate. Under anaerobic conditions, a nitro-nitrite isomerization delivers the amide oxygen from nitro oxygen. The same homolytic nitro-carbon fragmentation can be diverted by capture of the carbon radical intermediate with oxygen gas (O(2)) to deliver the amide oxygen from O(2). This understanding was used to develop a straightforward protocol for the preparation of (18)O-labeled amides in peptides by simply performing the umpolung amide synthesis reaction under an atmosphere of 18O2.

  1. Enhanced Cellular Uptake and Pharmacokinetic Characteristics of Doxorubicin-Valine Amide Prodrug.

    Science.gov (United States)

    Park, Yohan; Park, Ju-Hwan; Park, Suryeon; Lee, Song Yi; Cho, Kwan Hyung; Kim, Dae-Duk; Shim, Won-Sik; Yoon, In-Soo; Cho, Hyun-Jong; Maeng, Han-Joo

    2016-09-22

    In this study, we synthesized the valine (Val)-conjugated amide prodrug of doxorubicin (DOX) by the formation of amide bonds between DOX and Val. The synthesis of the DOX-Val prodrug was identified by a proton nuclear magnetic resonance (¹H-NMR) assay. In the MCF-7 cells (human breast adenocarcinoma cell; amino acid transporter-positive cell), the cellular accumulation efficiency of DOX-Val was higher than that of DOX according to the flow cytometry analysis data. Using confocal laser scanning microscopy (CLSM) imaging, it was confirmed that DOX-Val as well as DOX was mainly distributed in the nucleus of cancer cells. DOX-Val was intravenously administered to rats at a dose of 4 mg/kg, and the plasma concentrations of DOX-Val (prodrug) and DOX (formed metabolite) were quantitatively determined. Based on the systemic exposure (represented as area under the curve (AUC) values) of DOX-Val (prodrug) and DOX (formed metabolite), approximately half of DOX-Val seemed to be metabolized into DOX. However, it is expected that the remaining DOX-Val may exert improved cellular uptake efficiency in cancer cells after its delivery to the cancer region.

  2. Amide bond cleavage initiated by coordination with transition metal ions and tuned by an auxiliary ligand.

    Science.gov (United States)

    Yang, Yongpo; Lu, Chunxin; Wang, Hailong; Liu, Xiaoming

    2016-06-21

    The reaction of ligand , N,N-bis(pyridin-2-ylmethyl)acetamide, with five transition metal salts, FeCl3·6H2O, CuCl2·2H2O, Cu(ClO4)2·6H2O, ZnCl2 and K2PtCl4/KI, produced five metal complexes, [(μ-O)(FeClL')(FeCl3)] (), [CuLCl2] (), [CuBPA(ClO4)(CHCN)] ClO4 (), [ZnLCl2] () and [PtLI2] (), where = 1-(2,4,5-tri(pyridin-2-yl)-3-(pyridin-2-ylmethyl)imidazolidin-1-yl)ethanone which formed in situ, and BPA = bis(pyridin-2-ylmethyl)amine. The ligand and complexes were characterized by a variety of spectroscopic techniques including X-ray single crystal diffraction where applicable. Depending on the metal ion and auxiliary ligand of the complex, the acetyl group of the ligand could be either intact or cleaved. When ferric chloride hexahydrate was used, the deacetylation proceeded even further and a novel heterocyclic compound () was formed in situ. A possible mechanism was proposed for the formation of the heterocyclic compound found in complex . Our results indicate that to cleave effectively an amide bond, it is essential for a metal centre to bind to the amide bond and the metal centre is of sufficient Lewis acidity.

  3. Amidation reaction of eugenyl oxyacetate ethyl ester with 1,3 diaminopropane

    Science.gov (United States)

    Suryanti, V.; Wibowo, F. R.; Kusumaningsih, T.; Wibowo, A. H.; Khumaidah, S. A.; Wijayanti, L. A.

    2016-04-01

    Eugenol having various substituents on the aromatic ring (hydroxy, methoxy and allyl) are useful for starting material in synthesizing of its derivatives. Eugenol derivatives have shown wide future potential applications in many areas, especially as future drugs against many diseases. The aim of this work was to synthesize an amide of eugenol derivative. The starting material used was eugenol from clove oil and the reaction was conducted in 3 step reactions to give the final product. Firstly, eugenol was converted into eugenyl oxyacetate [2-(4-allyl-2-methoxyphenoxy) acetic acid] as a white crystal with 70.5% yield, which was then esterified with ethanol to have eugenyl oxyacetate ethyl ester [ethyl 2-(4-allyl-2-methoxyphenoxy) acetate] as brown liquid in 75.7%. The last step was the reaction between eugenyl oxyacetate ethyl ester and 1,3 diaminopropane to give 2-(4-allyl-2-methoxyphenoxy)-N-(3-aminopropyl) acetamide as a brown powder with 71.6% yield, where the amidation reaction was occurred.

  4. Papain-like protease (PLpro) inhibitory effects of cinnamic amides from Tribulus terrestris fruits.

    Science.gov (United States)

    Song, Yeong Hun; Kim, Dae Wook; Curtis-Long, Marcus John; Yuk, Heung Joo; Wang, Yan; Zhuang, Ningning; Lee, Kon Ho; Jeon, Kwon Seok; Park, Ki Hun

    2014-01-01

    Tribulus terrestris fruits are well known for their usage in pharmaceutical preparations and food supplements. The methanol extract of T. terrestris fruits showed potent inhibition against the papain-like protease (PLpro), an essential proteolylic enzyme for protection to pathogenic virus and bacteria. Subsequent bioactivity-guided fractionation of this extract led to six cinnamic amides (1-6) and ferulic acid (7). Compound 6 emerged as new compound possessing the very rare carbinolamide motif. These compounds (1-7) were evaluated for severe acute respiratory syndrome coronavirus (SARS-CoV) PLpro inhibitory activity to identify their potencies and kinetic behavior. Compounds (1-6) displayed significant inhibitory activity with IC50 values in the range 15.8-70.1 µM. The new cinnamic amide 6 was found to be most potent inhibitor with an IC50 of 15.8 µM. In kinetic studies, all inhibitors exhibited mixed type inhibition. Furthermore, the most active PLpro inhibitors (1-6) were proven to be present in the native fruits in high quantities by HPLC chromatogram and liquid chromatography with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI/MS).

  5. Enhanced Cellular Uptake and Pharmacokinetic Characteristics of Doxorubicin-Valine Amide Prodrug

    Directory of Open Access Journals (Sweden)

    Yohan Park

    2016-09-01

    Full Text Available In this study, we synthesized the valine (Val-conjugated amide prodrug of doxorubicin (DOX by the formation of amide bonds between DOX and Val. The synthesis of the DOX-Val prodrug was identified by a proton nuclear magnetic resonance (1H-NMR assay. In the MCF-7 cells (human breast adenocarcinoma cell; amino acid transporter–positive cell, the cellular accumulation efficiency of DOX-Val was higher than that of DOX according to the flow cytometry analysis data. Using confocal laser scanning microscopy (CLSM imaging, it was confirmed that DOX-Val as well as DOX was mainly distributed in the nucleus of cancer cells. DOX-Val was intravenously administered to rats at a dose of 4 mg/kg, and the plasma concentrations of DOX-Val (prodrug and DOX (formed metabolite were quantitatively determined. Based on the systemic exposure (represented as area under the curve (AUC values of DOX-Val (prodrug and DOX (formed metabolite, approximately half of DOX-Val seemed to be metabolized into DOX. However, it is expected that the remaining DOX-Val may exert improved cellular uptake efficiency in cancer cells after its delivery to the cancer region.

  6. 纳米腐植酸/丙烯酸-丙烯酰胺-蒙脱土复合型树脂的制备与表征%Preparation and characterization of nanoscale humic acid /poly(acrylic acid-acryl amide)-co-montorillonite composite resin

    Institute of Scientific and Technical Information of China (English)

    程亮; 侯翠红; 徐丽; 雒廷亮; 张保林; 刘国际

    2016-01-01

    The composite resins based on (acrylic acid-acrylamide)-motorillonite/nano humic acid were prepared by aqueous solution polymerization,using methylene-bis-acrylamide as cross-linking agent,potassium persulfate as initiator,acrylic acid,acrylamide,nano humic acid and modified montmorillonite as material.The effects of the monomer ratio (mass ratio ),nano-humic acid content,reaction temperature were systematically studied through single factor and orthogonal experiment.The optimum conditions were as follows:the monomer ratio 3:7 ,nano humic acid content 15%(mass fraction),reaction temperature 65℃,neutralization degree 80%(mass fraction), cross-linking agent content 0.05% (mass fraction),and initiator content 1.0% (mass fraction).The water absorption rate and salt absorption rate of the prepared composite resins were 998.90 g/g and 102.59 g/g, respectively.The product was characterized by FT-IR,SEM and TG-DSC,and the results showed that the grafting reaction took place among nanoscale humic acid and acrylamide,and ether bond emerged;the surface was rough and had loose structure,there were also many holes,voids and pits;it had a good thermal stability.%以N,N-亚甲基双丙烯酰胺为交联剂,过二硫酸钾为引发剂,丙烯酸、丙烯酰胺、纳米腐植酸及改性蒙脱土为原料,采用水溶液聚合法制备了丙烯酸-丙烯酰胺/纳米腐植酸基复合型树脂.通过单因素及正交实验系统考察了单体比(质量比)、纳米腐植酸用量、反应温度等因素对复合型树脂吸液倍率的影响.最适宜制备工艺条件为:单体比3:7,纳米腐植酸用量为15%,反应温度65℃,中和度80%,交联剂0.05%,引发剂1.0%,所制备的复合型树脂吸水和吸盐倍率分别为998.90 g/g及102.59 g/g.用FT-IR,SEM及TG-DSC等对产物进行表征,结果表明:纳米腐植酸与丙烯酰胺发生接枝反应,产生了醚键;其表面结构疏松且粗糙,呈现较多孔洞、空隙及凹坑;热稳定性较好.

  7. A beta-l-Arabinopyranosidase from Streptomyces avermitilis is a novel member of glycoside hydrolase family 27.

    Science.gov (United States)

    Ichinose, Hitomi; Fujimoto, Zui; Honda, Mariko; Harazono, Koichi; Nishimoto, Yukifumi; Uzura, Atsuko; Kaneko, Satoshi

    2009-09-11

    Arabinogalactan proteins (AGPs) are a family of plant cell surface proteoglycans and are considered to be involved in plant growth and development. Because AGPs are very complex molecules, glycoside hydrolases capable of degrading AGPs are powerful tools for analyses of the AGPs. We previously reported such enzymes from Streptomyces avermitilis. Recently, a beta-l-arabinopyranosidase was purified from the culture supernatant of the bacterium, and its corresponding gene was identified. The primary structure of the protein revealed that the catalytic module was highly similar to that of glycoside hydrolase family 27 (GH27) alpha-d-galactosidases. The recombinant protein was successfully expressed as a secreted 64-kDa protein using a Streptomyces expression system. The specific activity toward p-nitrophenyl-beta-l-arabinopyranoside was 18 micromol of arabinose/min/mg, which was 67 times higher than that toward p- nitrophenyl-alpha-d-galactopyranoside. The enzyme could remove 0.1 and 45% l-arabinose from gum arabic or larch arabinogalactan, respectively. X-ray crystallographic analysis reveals that the protein had a GH27 catalytic domain, an antiparallel beta-domain containing Greek key motifs, another antiparallel beta-domain forming a jellyroll structure, and a carbohydrate-binding module family 13 domain. Comparison of the structure of this protein with that of alpha-d-galactosidase showed a single amino acid substitution (aspartic acid to glutamic acid) in the catalytic pocket of beta-l-arabinopyranosidase, and a space for the hydroxymethyl group on the C-5 carbon of d-galactose bound to alpha-galactosidase was changed in beta-l-arabinopyranosidase. Mutagenesis study revealed that the residue is critical for modulating the enzyme activity. This is the first report in which beta-l-arabinopyranosidase is classified as a new member of the GH27 family.

  8. The PE16 (Rv1430 of Mycobacterium tuberculosis is an esterase belonging to serine hydrolase superfamily of proteins.

    Directory of Open Access Journals (Sweden)

    Rafiya Sultana

    Full Text Available The PE and PPE multigene families, first discovered during the sequencing of M. tuberculosis H37Rv genome are responsible for antigenic variation and have been shown to induce increased humoral and cell mediated immune response in the host. Using the bioinformatics tools, we had earlier reported that the 225 amino acid residue PE-PPE domain (Pfam: PF08237 common to some PE and PPE proteins has a "serine α/β hydrolase" fold and conserved Ser, Asp and His catalytic triad characteristic of lipase, esterase and cutinase activities. In order to prove experimentally that PE-PPE domain is indeed a serine hydrolase, we have cloned the full-length Rv1430 and its PE-PPE domain into pET-28a vector, expressed the proteins in E. coli and purified to homogeneity. The activity assays of both purified proteins were carried out using p-nitrophenyl esters of aliphatic carboxylic acids with varying chain length (C2-C16 to study the substrate specificity. To characterize the active site of the PE-PPE domain, we mutated the Ser199 to Ala. The activity of the protein in the presence of serine protease inhibitor- PMSF and the mutant protein were measured. Our results reveal that Rv1430 and its PE-PPE domain possess esterase activity and hydrolyse short to medium chain fatty acid esters with the highest specific activity for pNPC6 at 37°C, 38°C and pH 7.0, 8.0. The details of this work and the observed results are reported in this manuscript.

  9. Anion complexation with cyanobenzoyl substituted first and second generation tripodal amide receptors: crystal structure and solution studies.

    Science.gov (United States)

    Hoque, Md Najbul; Gogoi, Abhijit; Das, Gopal

    2015-09-14

    Anion complexation properties of two new tripodal amide receptors have been extensively studied here. Two tripodal receptors have been synthesized from the reaction of cyanobenzoyl acid chloride with two tri-amine building blocks such as (i) tris(2-aminoethyl)amine and (ii) tris(2-(4-aminophenoxy)ethyl)amine, which resulted in the first (L1) and second (L2) generation tripodal amides respectively. A detailed comparison of their coordination behavior with anions is also described by crystallographic and solution state experiments. The crystal structure demonstrates various types of spatial orientations of tripodal arms in two receptors and concomitantly interacts with anions distinctively. Intramolecular H-bonding between amide N–H and CO prevents opening of the receptor cavity in the crystal, which leads to a locked conformation of L1 having C(3v) symmetry and makes amide hydrogen unavailable for the anion which results in side cleft anion binding. However, in L2 we conveniently shift the anion binding sites to a distant position which increases cavity size as well as rules out any intramolecular H-bonding between amide N–H and CO. The crystal structure shows a different orientation of the arms in L2; it adopts a quasi-planar arrangement with C(2v) symmetry. In the crystal structure two arms are pointed in the same direction and while extending the contact the third arm is H-bonded with the apical N-atom through a –CN group, making a pseudo capsular cavity where the anion interacts. Most importantly spatial reorientation of the receptor L2 from a C(2v) symmetry to a folded conformation with a C(3v) symmetry was observed only in the presence of an octahedral SiF6(2-) anion and forms a sandwich type complex. Receptors L1 and L2 are explored for their solution state anion binding abilities. The substantial changes in chemical shifts were observed for the amide (-NH) and aromatic hydrogen (-CH) (especially for F(-)), indicating the role of these hydrogens in

  10. Synthetic polyspermine imidazole-4, 5-amide as an efficient and cytotoxicity-free gene delivery system

    Directory of Open Access Journals (Sweden)

    Duan S

    2012-07-01

    Full Text Available Shi-Yue Duan, Xue-Mei Ge, Nan Lu, Fei Wu, Weien Yuan, Tuo JinSchool of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of ChinaAbstract: A chemically dynamic spermine-based polymer: polyspermine imidazole-4, 5-amide (PSIA, Mw > 7 kDa was designed, synthesized, and evaluated in terms of its ability to deliver nucleic acids. This polymer was made from an endogenous monomer professionally condensing genes in sperms, spermine, and a known safety drug metabolite, imidazole-4, 5-dicarboxylic acid, through a bis-amide bond conjugated with the imidazole ring. This polymer can condense pDNA at a W/W ratio above 10 to form polyplexes (100–200 nm in diameter, which is consistent with the observation by transmission electron microscopy (TEM, and the zeta potential was in the range of 10–20 mV. The pDNA packaged polymer was stable in phosphate buffer solution (PBS at pH 7.4 (simulated body fluid while the polyplexes were releasing pDNA into the solution at pH 5.8 (simulated endo-lysosomes due to the degradation of the bis-amide linkages in response to changes in pH values. PSIA-polyplexes were able to achieve efficient cellular uptake and luciferase gene silencing by co-transfection of pDNA and siRNA in COS-7 cells and HepG2 cells with negligible cytotoxicity. Biodistribution of Rhodamine B-labeled PSIA-polyplexes after being systemically injected in BALB/c nude-mice showed that the polyplexes circulated throughout the body, accumulated mainly in the kidney at 4 hours of sample administration, and moved to the liver and spleen after 24 hours. All the results suggested that PSIA offered a promising example to balance the transfection efficiency and toxicity of a synthetic carrier system for the delivery of therapeutic nucleic acids.Keywords: gene delivery, polyspermine, cytotoxicity, transfection efficiency, biodistribution

  11. Inhibition of the soluble epoxide hydrolase promotes albuminuria in mice with progressive renal disease.

    Directory of Open Access Journals (Sweden)

    Oliver Jung

    Full Text Available Epoxyeicotrienoic acids (EETs are cytochrome P450-dependent anti-hypertensive and anti-inflammatory derivatives of arachidonic acid, which are highly abundant in the kidney and considered reno-protective. EETs are degraded by the enzyme soluble epoxide hydrolase (sEH and sEH inhibitors are considered treatment for chronic renal failure (CRF. We determined whether sEH inhibition attenuates the progression of CRF in the 5/6-nephrectomy model (5/6-Nx in mice. 5/6-Nx mice were treated with a placebo, an ACE-inhibitor (Ramipril, 40 mg/kg, the sEH-inhibitor cAUCB or the CYP-inhibitor fenbendazole for 8 weeks. 5/6-Nx induced hypertension, albuminuria, glomerulosclerosis and tubulo-interstitial damage and these effects were attenuated by Ramipril. In contrast, cAUCB failed to lower the blood pressure and albuminuria was more severe as compared to placebo. Plasma EET-levels were doubled in 5/6 Nx-mice as compared to sham mice receiving placebo. Renal sEH expression was attenuated in 5/6-Nx mice but cAUCB in these animals still further increased the EET-level. cAUCB also increased 5-HETE and 15-HETE, which derive from peroxidation or lipoxygenases. Similar to cAUCB, CYP450 inhibition increased HETEs and promoted albuminuria. Thus, sEH-inhibition failed to elicit protective effects in the 5/6-Nx model and showed a tendency to aggravate the disease. These effects might be consequence of a shift of arachidonic acid metabolism into the lipoxygenase pathway.

  12. Identification and in vitro analysis of the GatD/MurT enzyme-complex catalyzing lipid II amidation in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Daniela Münch

    2012-01-01

    Full Text Available The peptidoglycan of Staphylococcus aureus is characterized by a high degree of crosslinking and almost completely lacks free carboxyl groups, due to amidation of the D-glutamic acid in the stem peptide. Amidation of peptidoglycan has been proposed to play a decisive role in polymerization of cell wall building blocks, correlating with the crosslinking of neighboring peptidoglycan stem peptides. Mutants with a reduced degree of amidation are less viable and show increased susceptibility to methicillin. We identified the enzymes catalyzing the formation of D-glutamine in position 2 of the stem peptide. We provide biochemical evidence that the reaction is catalyzed by a glutamine amidotransferase-like protein and a Mur ligase homologue, encoded by SA1707 and SA1708, respectively. Both proteins, for which we propose the designation GatD and MurT, are required for amidation and appear to form a physically stable bi-enzyme complex. To investigate the reaction in vitro we purified recombinant GatD and MurT His-tag fusion proteins and their potential substrates, i.e. UDP-MurNAc-pentapeptide, as well as the membrane-bound cell wall precursors lipid I, lipid II and lipid II-Gly₅. In vitro amidation occurred with all bactoprenol-bound intermediates, suggesting that in vivo lipid II and/or lipid II-Gly₅ may be substrates for GatD/MurT. Inactivation of the GatD active site abolished lipid II amidation. Both, murT and gatD are organized in an operon and are essential genes of S. aureus. BLAST analysis revealed the presence of homologous transcriptional units in a number of gram-positive pathogens, e.g. Mycobacterium tuberculosis, Streptococcus pneumonia and Clostridium perfringens, all known to have a D-iso-glutamine containing PG. A less negatively charged PG reduces susceptibility towards defensins and may play a general role in innate immune signaling.

  13. Investigating the role of a backbone to substrate hydrogen bond in OMP decarboxylase using a site-specific amide to ester substitution.

    Science.gov (United States)

    Desai, Bijoy J; Goto, Yuki; Cembran, Alessandro; Fedorov, Alexander A; Almo, Steven C; Gao, Jiali; Suga, Hiroaki; Gerlt, John A

    2014-10-21

    Hydrogen bonds between backbone amide groups of enzymes and their substrates are often observed, but their importance in substrate binding and/or catalysis is not easy to investigate experimentally. We describe the generation and kinetic characterization of a backbone amide to ester substitution in the orotidine 5'-monophosphate (OMP) decarboxylase from Methanobacter thermoautotrophicum (MtOMPDC) to determine the importance of a backbone amide-substrate hydrogen bond. The MtOMPDC-catalyzed reaction is characterized by a rate enhancement (∼10(17)) that is among the largest for enzyme-catalyzed reactions. The reaction proceeds through a vinyl anion intermediate that may be stabilized by hydrogen bonding interaction between the backbone amide of a conserved active site serine residue (Ser-127) and oxygen (O4) of the pyrimidine moiety and/or electrostatic interactions with the conserved general acidic lysine (Lys-72). In vitro translation in conjunction with amber suppression using an orthogonal amber tRNA charged with L-glycerate ((HO)S) was used to generate the ester backbone substitution (S127(HO)S). With 5-fluoro OMP (FOMP) as substrate, the amide to ester substitution increased the value of Km by ∼1.5-fold and decreased the value of kcat by ∼50-fold. We conclude that (i) the hydrogen bond between the backbone amide of Ser-127 and O4 of the pyrimidine moiety contributes a modest factor (∼10(2)) to the 10(17) rate enhancement and (ii) the stabilization of the anionic intermediate is accomplished by electrostatic interactions, including its proximity of Lys-72. These conclusions are in good agreement with predictions obtained from hybrid quantum mechanical/molecular mechanical calculations.

  14. Adipose triglyceride lipase is a TG hydrolase of the small intestine and regulates intestinal PPARα signaling.

    Science.gov (United States)

    Obrowsky, Sascha; Chandak, Prakash G; Patankar, Jay V; Povoden, Silvia; Schlager, Stefanie; Kershaw, Erin E; Bogner-Strauss, Juliane G; Hoefler, Gerald; Levak-Frank, Sanja; Kratky, Dagmar

    2013-02-01

    Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme mediating triglyceride (TG) hydrolysis. The lack of ATGL results in TG accumulation in multiple tissues, underscoring the critical role of ATGL in maintaining lipid homeostasis. Recent evidence suggests that ATGL affects TG metabolism via activation of peroxisome proliferator-activated receptor α (PPARα). To investigate specific effects of intestinal ATGL on lipid metabolism we generated mice lacking ATGL exclusively in the intestine (ATGLiKO). We found decreased TG hydrolase activity and increased intracellular TG content in ATGLiKO small intestines. Intragastric administration of [(3)H]trioleate resulted in the accumulation of radioactive TG in the intestine, whereas absorption into the systemic circulation was unchanged. Intraperitoneally injected [(3)H]oleate also accumulated within TG in ATGLiKO intestines, indicating that ATGL mobilizes fatty acids from the systemic circulation absorbed by the basolateral side from the blood. Down-regulation of PPARα target genes suggested modulation of cholesterol absorption by intestinal ATGL. Accordingly, ATGL deficiency in the intestine resulted in delayed cholesterol absorption. Importantly, this study provides evidence that ATGL has no impact on intestinal TG absorption but hydrolyzes TGs taken up from the intestinal lumen and systemic circulation. Our data support the role of ATGL in modulating PPARα-dependent processes also in the small intestine.

  15. A novel ubiquitin carboxyl terminal hydrolase is involved in toad oocyte maturation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13suc1-agaroseaffinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accessionnumber: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% iden-tities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functionaldomains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit theprogesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant proteinp28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis,a classical catalytic reaction for ubiquitin carboxyl terminai hydrolases (UCHs). The results in this paperreveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in theprocess of progesterone-induced oocyte maturation possibly through an involvement in protein turnover anddegradation.

  16. Affinity chromatography using protein immobilized via arginine residues: purification of ubiquitin carboxyl-terminal hydrolases.

    Science.gov (United States)

    Duerksen-Hughes, P J; Williamson, M M; Wilkinson, K D

    1989-10-17

    4-(Oxoacetyl)phenoxyacetic acid (OAPA) forms a stable, covalent bond between its glyoxal group and the guanidino group of arginine and arginine derivatives [Duerksen, P. J., & Wilkinson, K. D. (1987) Anal. Biochem. 160, 444-454]. Studies were carried out to determine the chemical nature of this linkage, and the structure of the stable adduct between OAPA and methylguanidine was elucidated. The stable product results from an internal oxidation-reduction of the Schiff base adduct to form a cyclic alpha-aminoamide, 4-[4-(carboxymethoxy)phenyl]-2-(methylimino)-5-oxoimidazolidine. OAPA coupled to polyacrylamide beads was used to immobilize ubiquitin via its arginine residues, and the resulting affinity support was shown to specifically and reversibly bind a previously described enzyme, ubiquitin carboxyl-terminal hydrolase [Pickart, C. M., & Rose, I. A. (1985) J. Biol. Chem. 260, 7903-7910]. The resin was then used to isolate three newly identified ubiquitin carboxyl-terminal hydrolytic activities, which did not bind to ubiquitin immobilized via lysine residues. Significant purification was achieved in each case, and one isozyme was further purified to homogeneity.

  17. Bacillus thuringiensis peptidoglycan hydrolase SleB171 involved in daughter cell separation during cell division.

    Science.gov (United States)

    Li, Hua; Hu, Penggao; Zhao, Xiuyun; Yu, Ziniu; Li, Lin

    2016-04-01

    Whole-genome analyses have revealed a putative cell wall hydrolase gene (sleB171) that constitutes an operon with two other genes (ypeBandyhcN) of unknown function inBacillus thuringiensisBMB171. The putative SleB171 protein consists of 259 amino acids and has a molecular weight of 28.3 kDa. Gene disruption ofsleB171in the BMB171 genome causes the formation of long cell chains during the vegetative growth phase and delays spore formation and spore release, although it has no significant effect on cell growth and the ultimate release of the spores. The inseparable vegetative cells were nearly restored through the complementation ofsleB171expression. Real-time quantitative polymerase chain reaction analysis revealed thatsleB171is mainly active in the vegetative growth phase, with a maximum activity at the early stationary growth phase. Western blot analysis also confirmed thatsleB171is preferentially expressed during the vegetative growth phase. These results demonstrated that SleB171 plays an essential role in the daughter cell separation during cell division.

  18. Hormone-sensitive lipase (HSL) is also a retinyl ester hydrolase: evidence from mice lacking HSL.

    Science.gov (United States)

    Ström, Kristoffer; Gundersen, Thomas E; Hansson, Ola; Lucas, Stéphanie; Fernandez, Céline; Blomhoff, Rune; Holm, Cecilia

    2009-07-01

    Here, we investigated the importance of hormone-sensitive lipase (HSL) as a retinyl ester hydrolase (REH). REH activity was measured in vitro using recombinant HSL and retinyl palmitate. The expression of retinoic acid (RA)-regulated genes and retinoid metabolites were measured in high-fat diet fed HSL-null mice using real-time quantitative PCR and triple-stage liquid chromatography/tandem mass spectrometry, respectively. Age- and gender-matched wild-type littermates were used as controls. The REH activity of rat HSL was found to be higher than that against the hitherto best known HSL substrate, i.e., diacylglycerols. REH activity in white adipose tissue (WAT) of HSL-null mice was completely blunted and accompanied by increased levels of retinyl esters and decreased levels of retinol, retinaldehyde and all-trans RA. Accordingly, genes known to be positively regulated by RA were down-regulated in HSL-null mice, including pRb and RIP140, key factors promoting differentiation into the white over the brown adipocyte lineage. Dietary RA supplementation partly restored WAT mass and the expression of RA-regulated genes in WAT of HSL-null mice. These findings demonstrate the importance of HSL as an REH of adipose tissue and suggest that HSL via this action provides RA and other retinoids for signaling events that are crucial for adipocyte differentiation and lineage commitment.

  19. Structure-Based Optimization of Arylamides as Inhibitors of Soluble Epoxide Hydrolase

    Energy Technology Data Exchange (ETDEWEB)

    Eldrup, Anne B.; Soleymanzadeh, Fariba; Taylor, Steven J.; Muegge, Ingo; Farrow, Neil A.; Joseph, David; McKellop, Keith; Man, Chuk C.; Kukulka, Alison; De Lombaert, Stephane; (Boehringer)

    2009-11-04

    Inhibition of soluble epoxide hydrolase (sEH) is hypothesized to lead to an increase in circulating levels of epoxyeicosatrienoic acids, resulting in the potentiation of their in vivo pharmacological properties. As part of an effort to identify inhibitors of sEH with high and sustained plasma exposure, we recently performed a high throughput screen of our compound collection. The screen identified N-(3,3-diphenyl-propyl)-nicotinamide as a potent inhibitor of sEH. Further profiling of this lead revealed short metabolic half-lives in microsomes and rapid clearance in the rat. Consistent with these observations, the determination of the in vitro metabolic profile of N-(3,3-diphenyl-propyl)-nicotinamide in rat liver microsomes revealed extensive oxidative metabolism and a propensity for metabolite switching. Lead optimization, guided by the analysis of the solid-state costructure of N-(3,3-diphenyl-propyl)-nicotinamide bound to human sEH, led to the identification of a class of potent and selective inhibitors. An inhibitor from this class displayed an attractive in vitro metabolic profile and high and sustained plasma exposure in the rat after oral administration.

  20. Hydrolase stabilization via entanglement in poly(propylene sulfide) nanoparticles: stability towards reactive oxygen species

    Science.gov (United States)

    Allen, Brett L.; Johnson, Jermaine D.; Walker, Jeremy P.

    2012-07-01

    In the advancement of green syntheses and sustainable reactions, enzymatic biocatalysis offers extremely high reaction rates and selectivity that goes far beyond the reach of chemical catalysts; however, these enzymes suffer from typical environmental constraints, e.g. operational temperature, pH and tolerance to oxidative environments. A common hydrolase enzyme, diisopropylfluorophosphatase (DFPase, EC 3.1.8.2), has demonstrated a pronounced efficacy for the hydrolysis of a variety of substrates for potential toxin remediation, but suffers from the aforementioned limitations. As a means to enhance DFPase’s stability in oxidative environments, enzymatic covalent immobilization within the polymeric matrix of poly(propylene sulfide) (PPS) nanoparticles was performed. By modifying the enzyme’s exposed lysine residues via thiolation, DFPase is utilized as a comonomer/crosslinker in a mild emulsion polymerization. The resultant polymeric polysulfide shell acts as a ‘sacrificial barrier’ by first oxidizing to polysulfoxides and polysulfones, rendering DFPase in an active state. DFPase-PPS nanoparticles thus retain activity upon exposure to as high as 50 parts per million (ppm) of hypochlorous acid (HOCl), while native DFPase is observed as inactive at 500 parts per billion (ppb). This trend is also confirmed by enzyme-generated (chloroperoxidase (CPO), EC 1.11.1.10) reactive oxygen species (ROS) including both HOCl (3 ppm) and ClO2 (100 ppm).

  1. Tertiary structure and characterization of a glycoside hydrolase family 44 endoglucanase from Clostridium acetobutylicum.

    Science.gov (United States)

    Warner, Christopher D; Hoy, Julie A; Shilling, Taran C; Linnen, Michael J; Ginder, Nathaniel D; Ford, Clark F; Honzatko, Richard B; Reilly, Peter J

    2010-01-01

    A gene encoding a glycoside hydrolase family 44 (GH44) protein from Clostridium acetobutylicum ATCC 824 was synthesized and transformed into Escherichia coli. The previously uncharacterized protein was expressed with a C-terminal His tag and purified by nickel-nitrilotriacetic acid affinity chromatography. Crystallization and X-ray diffraction to a 2.2-A resolution revealed a triose phosphate isomerase (TIM) barrel-like structure with additional Greek key and beta-sandwich folds, similar to other GH44 crystal structures. The enzyme hydrolyzes cellotetraose and larger cellooligosaccharides, yielding an unbalanced product distribution, including some glucose. It attacks carboxymethylcellulose and xylan at approximately the same rates. Its activity on carboxymethylcellulose is much higher than that of the isolated C. acetobutylicum cellulosome. It also extensively converts lichenan to oligosaccharides of intermediate size and attacks Avicel to a limited extent. The enzyme has an optimal temperature in a 10-min assay of 55 degrees C and an optimal pH of 5.0.

  2. Expression, Purification and Crystal Structure of a Truncated Acylpeptide Hydrolase from Aeropyrum pernix K1

    Institute of Scientific and Technical Information of China (English)

    Hai-Feng ZHANG; Bai-Song ZHENG; Ying PENG; Zhi-Yong LOU; Yan FENG; Zi-He RAO

    2005-01-01

    Acylpeptide hydrolase (APH) catalyzes the N-terminal hydrolysis of Nα-acylpeptides to release Nα-acylated amino acids. The crystal structure of recombinant APH from the thermophilic archaeon Aeropyrum pernix K1 (apAPH) was reported recently to be at a resolution of 2.1 A using X-ray diffraction. A truncated mutant of apAPH that lacks the first short α-helix at the N-terminal, apAPH-△(1-21), was cloned, expressed,characterized and crystallized. Data from biochemical experiments indicate that the optimum temperature of apAPH is decreased by 15 ℃ with the deletion of the N-terminal α-helix. However, the enzyme activity at the optimal temperature does not change. It suggests that this N-terminal α-helix is essential for thermostability. Here, the crystal structure of apAPH-△(1-21) has been determined by molecular replacement to 2.5A. A comparison between the two structures suggests a difference in thermostability, and it can be concluded that by adding or deleting a linking structure (located over different domains), the stability or even the activity of an enzyme can be modified.

  3. Pharmacological inhibition of soluble epoxide hydrolase ameliorates diet-induced metabolic syndrome in rats.

    Science.gov (United States)

    Iyer, Abishek; Kauter, Kathleen; Alam, Md Ashraful; Hwang, Sung Hee; Morisseau, Christophe; Hammock, Bruce D; Brown, Lindsay

    2012-01-01

    The signs of metabolic syndrome following chronic excessive macronutrient intake include body weight gain, excess visceral adipose deposition, hyperglycaemia, glucose and insulin intolerances, hypertension, dyslipidaemia, endothelial damage, cardiovascular hypertrophy, inflammation, ventricular contractile dysfunction, fibrosis, and fatty liver disease. Recent studies show increased activity of soluble epoxide hydrolase (sEH) during obesity and metabolic dysfunction. We have tested whether sEH inhibition has therapeutic potential in a rat model of diet-induced metabolic syndrome. In these high-carbohydrate, high-fat-fed rats, chronic oral treatment with trans-4-[4-(3-adamantan-1-ylureido)-cyclohexyloxy]-benzoic acid (t-AUCB), a potent sEH inhibitor, alleviated the signs of metabolic syndrome in vivo including glucose, insulin, and lipid abnormalities, changes in pancreatic structure, increased systolic blood pressure, cardiovascular structural and functional abnormalities, and structural and functional changes in the liver. The present study describes the pharmacological responses to this selective sEH inhibitor in rats with the signs of diet-induced metabolic syndrome.

  4. Coacervate Core Micelles for the Dispersion and Stabilization of Organophosphate Hydrolase in Organic Solvents

    Science.gov (United States)

    Mills, Carolyn; Obermeyer, Allie; Dong, Xuehui; Olsen, Bradley D.

    Bulk organophosphate (OP) nerve agents are difficult to decontaminate on site and dangerous to transport. The organophosphate hydrolase (OPH) enzyme is an efficient catalyst for hydrolyzing, and thus decontaminating, these compounds, but suffers from poor stability in the hydrophobic bulk OP environment. Here, we exploit the complex coacervation phase separation phenomenon to form complex coacervate core micelles (C3Ms) that can protect this OPH enzyme under these conditions. Stable C3Ms form when mixing a charged-neutral block copolymer methyl-quaternized poly(4-vinylpyridine)-block-poly(oligo(ethylene glycol) methacrylate) (Qp4vp- b-POEGMA), a homopolymer poly(acrylic acid) (PAA), and OPH under a certain conditions. The C3Ms are then transferred into two organic solvents, ethanol and dimethyl methylphosphonate (DMMP), which is a good simulant for the physical properties of the OP compounds. The C3Ms retain their nanostructures in the organic solvents. The activity test of OPH indicates that the C3Ms successfully protect OPH activity in organic solvents.

  5. Characterization of a bifunctional enzyme with (p)ppGpp-hydrolase/synthase activity in Leptospira interrogans.

    Science.gov (United States)

    He, Ping; Deng, Cong; Liu, Boyu; Zeng, LingBing; Zhao, Wei; Zhang, Yan; Jiang, XuCheng; Guo, XiaoKui; Qin, JinHong

    2013-11-01

    Alarmone Guanosine 5'-diphosphate (or 5'-triphosphate) 3'-diphosphate [(p)ppGpp] is the key component that globally regulates stringent control in bacteria. There are two homologous enzymes, RelA and SpoT in Escherichia coli, which are responsible for fluctuations in (p)ppGpp concentration inside the cell, whereas there exists only a single RelA/SpoT enzyme in Gram-positive bacteria. We have identified a bifunctional enzyme with (p)ppGpp-hydrolase/synthase activity in Leptospira interrogans. We show that the relLin gene (LA_3085) encodes a protein that fully complements the relA/spoT double mutants in E. coli. The protein functions as a (p)ppGpp degradase as well as a (p)ppGpp synthase when the cells encounter amino acid stress and deprivation of carbon sources. N-terminus HD and RSD domains of relLin (relLinN ) were observed to restore growth of double mutants of E. coli. Finally, We demonstrate that purified RelLin and RelLinN show high (p)ppGpp synthesis activity in vitro. Taken together, our results suggest that L. interrogans contain a single Rel-like bifunctional protein, RelLin , which plays an important role in maintaining the basal level of (p)ppGpp in the cell potentially contributing to the regulation of bacterial stress response.

  6. Amide I'-II' 2D IR spectroscopy provides enhanced protein secondary structural sensitivity.

    Science.gov (United States)

    Deflores, Lauren P; Ganim, Ziad; Nicodemus, Rebecca A; Tokmakoff, Andrei

    2009-03-11

    We demonstrate how multimode 2D IR spectroscopy of the protein amide I' and II' vibrations can be used to distinguish protein secondary structure. Polarization-dependent amide I'-II' 2D IR experiments on poly-l-lysine in the beta-sheet, alpha-helix, and random coil conformations show that a combination of amide I' and II' diagonal and cross peaks can effectively distinguish between secondary structural content, where amide I' infrared spectroscopy alone cannot. The enhanced sensitivity arises from frequency and amplitude correlations between amide II' and amide I' spectra that reflect the symmetry of secondary structures. 2D IR surfaces are used to parametrize an excitonic model for the amide I'-II' manifold suitable to predict protein amide I'-II' spectra. This model reveals that the dominant vibrational interaction contributing to this sensitivity is a combination of negative amide II'-II' through-bond coupling and amide I'-II' coupling within the peptide unit. The empirically determined amide II'-II' couplings do not significantly vary with secondary structure: -8.5 cm(-1) for the beta sheet, -8.7 cm(-1) for the alpha helix, and -5 cm(-1) for the coil.

  7. Quantitative and structural analysis of amides and lignans in Zanthoxylum armatum by UPLC-DAD-ESI-QTOF-MS/MS.

    Science.gov (United States)

    Kumar, Vishal; Kumar, Shiv; Singh, Bikram; Kumar, Neeraj

    2014-06-01

    A rapid and simple ultra performance liquid chromatography-diode array detection (UPLC-DAD) method has been developed for the simultaneous quantification of four biologically important furofuran lignans, asarinin, sesamin, fargesin and kobusin, and an amide, armatamide in Zanthoxylum armatum within 7min. The separation was carried out on a BEH C18 column (2.1mm×100mm, 1.7μm particle size) with 0.05% formic acid aqueous solution and acetonitrile as mobile phase under gradient conditions at 25°C. The method was validated and found to be linear (R(2)≥0.9997), precise in terms of peak areas (intra-day RSDs≤0.62% and inter-day RSDs≤2.95%) and accurate (95.6-104.0%). The developed method was applied to the quality assessment of different parts (leaves, bark and seeds) of Z. armatum including locational variation of leaves samples. Significant variation in the amount of amides and furofuran lignans was observed. Tandem electrospray ionization-mass spectrometry (UPLC-DAD-ESI-MS/MS) of samples led to the identification of sixteen compounds in the category of amides and furofuran lignans.

  8. Etude du comportement chimique des additifs dispersants sur les surfaces métalliques. Réaction des fonctions amide sur l'alumine Study of the Chemical Behavior of Dispersant Additives on Metal Surfaces. Reaction of Amide Functions on Aluminum

    Directory of Open Access Journals (Sweden)

    Nechtschein J.

    2006-11-01

    Full Text Available Ce travail a pour objet la mise en évidence des réactions chimiques qui apparaissent entre les fonctions amides qui entrent dans la constitution de nombreuses formules de dispersants pour carburants et lubrifiants et la surface de l'aluminium. On montre que la réaction des amides sur la surface de l'alumine s'opère en deux étapes: La première étape, ou étape de chimisorption, fait intervenir les sites de Lewis et les groupements OH voisins de l'alumine pour fixer la fonction amide par le groupement carbonyle (liaison acide-base de Lewis et par l'azote (liaison hydrogène. La deuxième étape, ou étape d'hydrolyse, conduit à la formation d'un carboxylate de surface et d'une amine. The aim of this study was to analyze the chemical reactions that appear between the amide functions entering into the composition of numerous dispersant formulas for fuels and lubricants and the surface of aluminum. The reactions of amides on an aluminum surface is shown to take place in two stages. The first stage, or chemisorption stage, involves Lewis sites and the OH groups next to the aluminum oxide sa as to fix the amide function by the carbonyl group (Lewis acid-basic bonds and by nitrogen (hydrogen bond. The second stage, or hydrolysis stage, leads to the formation of a surface carboxylate and an amine.

  9. EFSA CEF Panel (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids), 2014. Scientific Opinion on Flavouring Group Evaluation 300, Revision 1 (FGE.300Rev1): One cyclo-aliphatic amide from chemical group 33

    DEFF Research Database (Denmark)

    Beltoft, Vibe Meister; Frandsen, Henrik Lauritz; Nørby, Karin Kristiane

    The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate a flavouring substance,cyclopropanecarboxylic acid (2-isopropyl-5-methyl-cyclohexyl)-amide [FL-no: 16.115] in the Flavouring Group Evaluation 300, Revision 1...... (FGE.300Rev1) using the Procedure in Commission Regulation (EC) No 1565/2000. This revision is made due to a re-evaluation of the flavouring substance, cyclopropanecarboxylic acid (2-isopropyl-5-methyl-cyclohexyl)-amide [FL-no: 16.115], as a 90-day dietary study in rats has become available...

  10. An improved method for specificity annotation shows a distinct evolutionary divergence among the microbial enzymes of the cholylglycine hydrolase family.

    Science.gov (United States)

    Panigrahi, Priyabrata; Sule, Manas; Sharma, Ranu; Ramasamy, Sureshkumar; Suresh, C G

    2014-06-01

    Bile salt hydrolases (BSHs) are gut microbial enzymes that play a significant role in the bile acid modification pathway. Penicillin V acylases (PVAs) are enzymes produced by environmental microbes, having a possible role in pathogenesis or scavenging of phenolic compounds in their microbial habitats. The correct annotation of such physiologically and industrially important enzymes is thus vital. The current methods relying solely on sequence homology do not always provide accurate annotations for these two members of the cholylglycine hydrolase (CGH) family as BSH/PVA enzymes. Here, we present an improved method [binding site similarity (BSS)-based scoring system] for the correct annotation of the CGH family members as BSH/PVA enzymes, which along with the phylogenetic information incorporates the substrate specificity as well as the binding site information. The BSS scoring system was developed through the analysis of the binding sites and binding modes of the available BSH/PVA structures with substrates glycocholic acid and penicillin V. The 198 sequences in the dataset were then annotated accurately using BSS scores as BSH/PVA enzymes. The dataset presented contained sequences from Gram-positive bacteria, Gram-negative bacteria and archaea. The clustering obtained for the dataset using the method described above showed a clear distinction in annotation of Gram-positive bacteria and Gram-negative bacteria. Based on this clustering and a detailed analysis of the sequences of the CGH family in the dataset, we could infer that the CGH genes might have evolved in accordance with the hypothesis stating the evolution of diderms and archaea from the monoderms.

  11. Structural Milestones in the Reaction Pathway of an Amide Hydrolase: Substrate, Acyl, and Product Complexes of Cephalothin with AmpC [beta]-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Beadle, Beth M.; Trehan, Indi; Focia, Pamela J.; Shoichet, Brian K. (NWU)

    2010-03-05

    {beta}-lactamases hydrolyze {beta}-lactam antibiotics and are the leading cause of bacterial resistance to these drugs. Although {beta}-lactamases have been extensively studied, structures of the substrate-enzyme and product-enzyme complexes have proven elusive. Here, the structure of a mutant AmpC in complex with the {beta}-lactam cephalothin in its substrate and product forms was determined by X-ray crystallography to 1.53 {angstrom} resolution. The acyl-enzyme intermediate between AmpC and cephalothin was determined to 2.06 {angstrom} resolution. The ligand undergoes a dramatic conformational change as the reaction progresses, with the characteristic six-membered dihydrothiazine ring of cephalothin rotating by 109{sup o}. These structures correspond to all three intermediates along the reaction path and provide insight into substrate recognition, catalysis, and product expulsion.

  12. Characterization and functional analysis of Trichinella spiralis Nudix hydrolase.

    Science.gov (United States)

    Long, Shao Rong; Wang, Zhong Quan; Jiang, Peng; Liu, Ruo Dan; Qi, Xin; Liu, Pei; Ren, Hui Jun; Shi, Hai Ning; Cui, Jing

    2015-12-01

    Trichinella spiralis Nudix hydrolase (TsNd) was identified by screening a T7 phage display cDNA library from T. spiralis intestinal infective larvae (IIL), and vaccination of mice with recombinant TsNd protein (rTsNd) or TsNd DNA vaccine produced a partial protective immunity. The aim of this study was to identify the characteristics and biological functions of TsNd in the process of invasion and development of T. spiralis larvae. Transcription and expression of TsNd gene at all developmental stages of T. spiralis were observed by qPCR and immunofluorescent test (IFT). The rTsNd had the Nd enzymatic activity to dGTP, NAD, NADP and CoA. Its kinetic properties on the preferred substrate dGTP were calculated, and the Vmax, Km, and kcat/Km values at pH 8.0 were 3.19 μM min(-1) μg(-1), 370 μM, and 144 s(-1) M(-1), respectively, in reaction matrix containing 5 mM Zn(2+) and 2 mM DTT. The rTsNd was active from 25 °C to 50 °C, with optimal activity at 37 °C. rTsNd was able to bind specifically to mouse intestinal epithelial cells (IECs) and promoted the larval invasion of IECs, whereas anti-rTsNd antibodies inhibited the larval invasion of IECs in a dose-dependent manner. Anti-rTsNd antibodies could kill T. spiralis infective larvae by an ADCC-mediated mechanism. Our results showed that the rTsNd protein was able to interact with host IECs, had the Nudix hydrolasing activity and the enzymatic activity appeared to be essential indispensable for the T. spiralis larval invasion, development and survival in host.

  13. Enzymatic synthesis of fatty amides from palm olein.

    Science.gov (United States)

    Al-Mulla, Emad A Jaffar; Yunus, Wan Md Zin Wan; Ibrahim, Nor Azowa Bt; Rahman, Mohd Zaki A

    2010-01-01

    Fatty amides have been successfully synthesized from palm olein and urea by a one-step lipase catalyzed reaction. The use of immobilized lipase as the catalyst for the preparation reaction provides an easy isolation of the enzyme from the products and other components in the reaction mixture. The fatty amides were characterized using Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance ((1)H NMR) technique and elemental analysis. The highest conversion percentage (96%) was obtained when the process was carried out for 36 hours using urea to palm oil ratio of 5.2: 1.0 at 40 degrees C. The method employed offers several advantages such as renewable and abundant of the raw material, simple reaction procedure, environmentally friendly process and high yield of the product.

  14. In vivo behavior of hydrogel beads based on amidated pectins.

    Science.gov (United States)

    Munjeri, O; Collett, J H; Fell, J T; Sharma, H L; Smith, A M

    1998-01-01

    Radio-labeled hydrogel beads, based on amidated pectin, have been produced by adding droplets of an amidated pectin solution to calcium chloride. Incorporation of model drugs into the beads and measurement of the dissolution rate showed that the properties of the beads were unaffected by the incorporation of the radiolabel. The labeled beads were used to carry out an in vivo study of their behavior in the gastrointestinal tract using human volunteers. The volunteers were given the beads after an overnight fast and images were obtained at frequent intervals during transit through the upper gastrointestinal tract and the colon. The beads exhibited rapid gastric emptying and proceeded to pass through the small intestine individually before regrouping at the ileo-caecal junction. Once in the colon, the beads again proceeded as individuals and evidence of the degradation of the beads was observed.

  15. Halo substituent effects on intramolecular cycloadditions involving furanyl amides.

    Science.gov (United States)

    Padwa, Albert; Crawford, Kenneth R; Straub, Christopher S; Pieniazek, Susan N; Houk, K N

    2006-07-21

    Intramolecular Diels-Alder reactions involving a series of N-alkenyl-substituted furanyl amides were investigated. Stable functionalized oxanorbornenes were formed in high yield upon heating at 80-110 degrees C. The cycloaddition reactions include several bromo-substituted furanyl amides, and these systems were found to proceed at a much faster rate and in higher yield than without substitution. This effect was observed by incorporating a halogen in the 3- or 5-position of the furan ring and appears to be general. The origin of increased cycloaddition rates for halo-substituted furans has been investigated with quantum mechanical calculations. The success of these reactions is attributed to increases in reaction exothermicities; this both decreases activation enthalpies and increases barriers to retrocycloadditions. Halogen substitution on furan increases reactant energy and stabilizes the product, which is attributed to the preference of electronegative halogens to be attached to a more highly alkylated and therefore more electropositive framework.

  16. Simulations of the temperature dependence of amide I vibration.

    Science.gov (United States)

    Kaminský, Jakub; Bouř, Petr; Kubelka, Jan

    2011-01-13

    For spectroscopic studies of peptide and protein thermal denaturation it is important to single out the contribution of the solvent to the spectral changes from those originated in the molecular structure. To obtain insights into the origin and size of the temperature solvent effects on the amide I spectra, combined molecular dynamics and density functional simulations were performed with the model N-methylacetamide molecule (NMA). The computations well reproduced frequency and intensity changes previously observed in aqueous NMA solutions. An empirical correction of vacuum frequencies in single NMA molecule based on the electrostatic potential of the water molecules provided superior results to a direct density functional average obtained for a limited number of solute-solvent clusters. The results thus confirm that the all-atom quantum and molecular mechanics approach captures the overall influence of the temperature dependent solvent properties on the amide I spectra and can improve the accuracy and reliability of molecular structural studies.

  17. Coumarin amide derivatives as fluorescence chemosensors for cyanide anions

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qianqian [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China); Liu, Zhiqiang [State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, Shandong (China); Cao, Duxia, E-mail: duxiacao@ujn.edu.cn [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China); Guan, Ruifang, E-mail: mse_guanrf@ujn.edu.cn [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China); Wang, Kangnan; Shan, Yanyan; Xu, Yongxiao; Ma, Lin [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China)

    2015-07-01

    Four coumarin amide derivatives with 4-methyl coumarin or pyrene as terminal group have been synthesized. Their photophysical properties and recognition properties for cyanide anions have been examined. The results indicate that the compounds can recognize cyanide anions with obvious absorption and fluorescence spectra change, at the same time, obvious color and fluorescence change can be observed by naked eye. The in situ hydrogen nuclear magnetic resonance spectra and photophysical properties change confirm that Michael additions between the chemosensors and cyanide anions take place at the 4-position of coumarin. - Highlights: • Four coumarin amide derivatives with 4-methyl coumarin or pyrene as terminal group were synthesized. • The compounds can recognize cyanide anions with obvious absorption and fluorescence spectra change. • Michael additions between the chemosensors and cyanide anions take place at the 4-position of coumarin.

  18. Cleavage of an amide bond by a ribozyme

    Science.gov (United States)

    Dai, X.; De Mesmaeker, A.; Joyce, G. F.; Miller, S. L. (Principal Investigator)

    1995-01-01

    A variant form of a group I ribozyme, optimized by in vitro evolution for its ability to catalyze magnesium-dependent phosphoester transfer reactions involving DNA substrates, also catalyzes the cleavage of an unactivated alkyl amide when that linkage is presented in the context of an oligodeoxynucleotide analog. Substrates containing an amide bond that joins either two DNA oligos, or a DNA oligo and a short peptide, are cleaved in a magnesium-dependent fashion to generate the expected products. The first-order rate constant, kcat, is 0.1 x 10(-5) min-1 to 1 x 10(-5) min-1 for the DNA-flanked substrates, which corresponds to a rate acceleration of more than 10(3) as compared with the uncatalyzed reaction.

  19. A novel amide stationary phase for hydrophilic interaction liquid chromatography and ion chromatography.

    Science.gov (United States)

    Shen, Guobin; Zhang, Feifang; Yang, Bingcheng; Chu, Changhu; Liang, Xinmiao

    2013-10-15

    A novel amide stationary phase (ASP) for hydrophilic interaction liquid chromatography (HILIC) has been prepared via the Click chemistry method. It was based on the strategy that the amino group of Asparagine was easily transferred to the corresponding azido group and then clicked onto terminal alkyne-silica gel in the presence of Cu(I)-based catalyst. For the tested polar compounds including nucleosides and nucleic acid bases, ASP-based column has demonstrated good performance in terms of separation efficiency and column stability, and the retention mechanism was found to match well the typical HILIC retention. In addition, the ASP described here showed much better selectivity in separation of inorganic anions under ion chromatography mode relative to other kinds of commercial ASP.

  20. Solid-phase synthesis of lidocaine and procainamide analogues using backbone amide linker (BAL) anchoring.

    Science.gov (United States)

    Shannon, Simon K; Peacock, Mandy J; Kates, Steven A; Barany, George

    2003-01-01

    New solid-phase strategies have been developed for the synthesis of lidocaine (1) and procainamide (2) analogues, using backbone amide linker (BAL) anchoring. Both sets were prepared starting from a common resin-bound intermediate, followed by four general steps: (i) attachment of a primary aliphatic or aromatic amine to the solid support via reductive amination (as monitored by a novel test involving reaction of 2,4-dinitrophenylhydrazine with residual aldehyde groups); (ii) acylation of the resultant secondary amine; (iii) displacement of halide with an amine; and (iv) trifluoroacetic acid-mediated release from the support. A manual parallel strategy was followed to provide 60 novel compounds, of which two dozen have not been previously described. In most cases, initial crude purities were >80%, and overall isolated yields were in the 40-88% range.

  1. Synthesis of Novel Chiral 7-Amide Substituted-4-androstene-3,17-dione Derivatives

    Institute of Scientific and Technical Information of China (English)

    CHEN Shao-rui; ZHOU Xue-qin; LI Wei; LIU Dong-zhi

    2011-01-01

    A series of novel 7-amide substituted-4-androstene-3,17-dione derivatives(8βαa-8αh or 8βa-8βh) was synthesized from the important intermediates 5 by N-acylation and acidic hydrolysis.Compounds 5a and 5β were obtained through the reaction sequence including acetalization,allylic oxidation,oximation and reduction.The structures of the target compounds were characterized by MS,1H NMR,13C NMR and HRMS spectra and their stereo configurations were identified through DEPT(distortionless enhancement by polarization transfer),HMQC(heteronuclear multiple quantum coherence) and NOE(nuclear overhauser effect) correlation.

  2. Interacting Blends of Novel Unsaturated Polyester Amide Resin with Vinyl Acetate

    Directory of Open Access Journals (Sweden)

    H. S. Patel

    2004-01-01

    Full Text Available Novel unsaturated poly (ester- amide resins (UPEAs were prepared by the reaction between an epoxy resin, namely diglycidyl ether of bisphenol–A (DGEBA and unsaturated aliphatic bisamic acids using a base catalyst. These UPEAs were then blended with a vinyl monomer namely, Vinyl acetate (VA to produce a homogeneous resin syrup. The curing of these UPEAs-VA resin blends was carried out by using benzoyl peroxide (BPO as an initiator for the radical polymerization and was monitored by using a differential scanning calorimeter (DSC. The glass fibre reinforced composites (i.e. laminates of these UPEA-VA resin blends were fabricated using the DSC data. The chemical, mechanical and electrical properties of the glass fibre composites have also been evaluated. The unreinforced cured samples of the UPEA-VA resin blends were also analyzed by thermogravimetry (TGA.

  3. Potent and orally efficacious benzothiazole amides as TRPV1 antagonists.

    Science.gov (United States)

    Besidski, Yevgeni; Brown, William; Bylund, Johan; Dabrowski, Michael; Dautrey, Sophie; Harter, Magali; Horoszok, Lucy; Hu, Yin; Johnson, Dean; Johnstone, Shawn; Jones, Paul; Leclerc, Sandrine; Kolmodin, Karin; Kers, Inger; Labarre, Maryse; Labrecque, Denis; Laird, Jennifer; Lundström, Therese; Martino, John; Maudet, Mickaël; Munro, Alexander; Nylöf, Martin; Penwell, Andrea; Rotticci, Didier; Slaitas, Andis; Sundgren-Andersson, Anna; Svensson, Mats; Terp, Gitte; Villanueva, Huascar; Walpole, Christopher; Zemribo, Ronald; Griffin, Andrew M

    2012-10-01

    Benzothiazole amides were identified as TRPV1 antagonists from high throughput screening using recombinant human TRPV1 receptor and structure-activity relationships were explored to pinpoint key pharmacophore interactions. By increasing aqueous solubility, through the attachment of polar groups to the benzothiazole core, and enhancing metabolic stability, by blocking metabolic sites, the drug-like properties and pharmokinetic profiles of benzothiazole compounds were sufficiently optimized such that their therapeutic potential could be verified in rat pharmacological models of pain.

  4. Guidelines for Middle Managers for Thriving amid Continuous Change

    OpenAIRE

    2016-01-01

    This thesis suggests the much needed guidelines for middle managers for thriving amid continuous change. Middle managers, being an integral part of their organizations, needed a set of consolidated guidelines for thriving in the times of continuous change. Thriving requires high engagement, learning and growth as a response in stressful situations. The proposed guidelines include elements from literature and recommendations of the middle managers which came from co-creation sessions with midd...

  5. An efficient computational model to predict protonation at the amide nitrogen and reactivity along the C-N rotational pathway.

    Science.gov (United States)

    Szostak, Roman; Aubé, Jeffrey; Szostak, Michal

    2015-04-14

    N-Protonation of amides is critical in numerous biological processes, including amide bonds proteolysis and protein folding as well as in organic synthesis as a method to activate amide bonds towards unconventional reactivity. A computational model enabling prediction of protonation at the amide bond nitrogen atom along the C-N rotational pathway is reported. Notably, this study provides a blueprint for the rational design and application of amides with a controlled degree of rotation in synthetic chemistry and biology.

  6. Synthesis, morphology and properties of segmented poly(ether ester amide)s comprising uniform glycine or β-alanine extended bisoxalamide hard segments

    NARCIS (Netherlands)

    Sijbrandi, N.J.; Kimenai, A.J.; Mes, E.P.C.; Broos, R.; Bar, G.; Rosenthal, M.; Odarchenko, Y.; Ivanov, D.A.; Feijen, J.; Dijkstra, P.J.

    2012-01-01

    Segmented poly(ether ester amide)s comprising glycine or β-alanine extended bisoxalamide hard segments are highly phase separated thermoplastic elastomers with a broad temperature independent rubber plateau. These materials with molecular weights, Mn, exceeding 30 × 103 g mol−1 are conveniently prep

  7. Identification and biochemical characterization of a GDSL-motif carboxylester hydrolase from Carica papaya latex.

    Science.gov (United States)

    Abdelkafi, Slim; Ogata, Hiroyuki; Barouh, Nathalie; Fouquet, Benjamin; Lebrun, Régine; Pina, Michel; Scheirlinckx, Frantz; Villeneuve, Pierre; Carrière, Frédéric

    2009-11-01

    An esterase (CpEst) showing high specific activities on tributyrin and short chain vinyl esters was obtained from Carica papaya latex after an extraction step with zwitterionic detergent and sonication, followed by gel filtration chromatography. Although the protein could not be purified to complete homogeneity due to its presence in high molecular mass aggregates, a major protein band with an apparent molecular mass of 41 kDa was obtained by SDS-PAGE. This material was digested with trypsin and the amino acid sequences of the tryptic peptides were determined by LC/ESI/MS/MS. These sequences were used to identify a partial cDNA (679 bp) from expressed sequence tags (ESTs) of C. papaya. Based upon EST sequences, a full-length gene was identified in the genome of C. papaya, with an open reading frame of 1029 bp encoding a protein of 343 amino acid residues, with a theoretical molecular mass of 38 kDa. From sequence analysis, CpEst was identified as a GDSL-motif carboxylester hydrolase belonging to the SGNH protein family and four potential N-glycosylation sites were identified. The putative catalytic triad was localised (Ser(35)-Asp(307)-His(310)) with the nucleophile serine being part of the GDSL-motif. A 3D-model of CpEst was built from known X-ray structures and sequence alignments and the catalytic triad was found to be exposed at the surface of the molecule, thus confirming the results of CpEst inhibition by tetrahydrolipstatin suggesting a direct accessibility of the inhibitor to the active site.

  8. Inhibition of soluble epoxide hydrolase in mice promotes reverse cholesterol transport and regression of atherosclerosis.

    Science.gov (United States)

    Shen, Li; Peng, Hongchun; Peng, Ran; Fan, Qingsong; Zhao, Shuiping; Xu, Danyan; Morisseau, Christophe; Chiamvimonvat, Nipavan; Hammock, Bruce D

    2015-04-01

    Adipose tissue is the body largest free cholesterol reservoir and abundantly expresses ATP binding cassette transporter A1 (ABCA1), which maintains plasma high-density lipoprotein (HDL) levels. HDLs have a protective role in atherosclerosis by mediating reverse cholesterol transport (RCT). Soluble epoxide hydrolase (sEH) is a cytosolic enzyme whose inhibition has various beneficial effects on cardiovascular disease. The sEH is highly expressed in adipocytes, and it converts epoxyeicosatrienoic acids (EETs) into less bioactive dihydroxyeicosatrienoic acids. We previously showed that increasing EETs levels with a sEH inhibitor (sEHI) (t-AUCB) resulted in elevated ABCA1 expression and promoted ABCA1-mediated cholesterol efflux from 3T3-L1 adipocytes. The present study investigates the impacts of t-AUCB in mice deficient for the low density lipoprotein (LDL) receptor (Ldlr(-/-) mice) with established atherosclerotic plaques. The sEH inhibitor delivered in vivo for 4 weeks decreased the activity of sEH in adipose tissue, enhanced ABCA1 expression and cholesterol efflux from adipose depots, and consequently increased HDL levels. Furthermore, t-AUCB enhanced RCT to the plasma, liver, bile and feces. It also showed the reduction of plasma LDL-C levels. Consistently, t-AUCB-treated mice showed reductions in the size of atherosclerotic plaques. These studies establish that raising adipose ABCA1 expression, cholesterol efflux, and plasma HDL levels with t-AUCB treatment promotes RCT, decreasing LDL-C and atherosclerosis regression, suggesting that sEH inhibition may be a promising strategy to treat atherosclerotic vascular disease.

  9. Ubiquitin C-Terminal Hydrolase L1 in Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Jennifer Hurst-Kennedy

    2012-01-01

    Full Text Available Ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1, aka PGP9.5 is an abundant, neuronal deubiquitinating enzyme that has also been suggested to possess E3 ubiquitin-protein ligase activity and/or stabilize ubiquitin monomers in vivo. Recent evidence implicates dysregulation of UCH-L1 in the pathogenesis and progression of human cancers. Although typically only expressed in neurons, high levels of UCH-L1 have been found in many nonneuronal tumors, including breast, colorectal, and pancreatic carcinomas. UCH-L1 has also been implicated in the regulation of metastasis and cell growth during the progression of nonsmall cell lung carcinoma, colorectal cancer, and lymphoma. Together these studies suggest UCH-L1 has a potent oncogenic role and drives tumor development. Conversely, others have observed promoter methylation-mediated silencing of UCH-L1 in certain tumor subtypes, suggesting a potential tumor suppressor role for UCH-L1. In this paper, we provide an overview of the evidence supporting the involvement of UCH-L1 in tumor development and discuss the potential mechanisms of action of UCH-L1 in oncogenesis.

  10. Molecular cloning and expression of a new α-neoagarobiose hydrolase from Agarivorans gilvus WH0801 and enzymatic production of 3,6-anhydro-l-galactose.

    Science.gov (United States)

    Liu, Nan; Yang, Meng; Mao, Xiangzhao; Mu, Bozhong; Wei, Dongzhi

    2016-01-01

    A new α-neoagarobiose hydrolase (NABH) called AgaWH117 was cloned from Agarivorans gilvus WH0801. The gene encoding this hydrolase consists of 1,086 bp and encodes a protein containing 361 amino acids. This new NABH showed 74% amino acid sequence identity with other known NABHs. The molecular mass of the recombinant AgaWH117 was estimated to be 41 kDa. Purified AgaWH117 showed endolytic activity during neoagarobiose degradation, yielding 3,6-anhydro-l-galactose (l-AHG) and d-galactose as products. It showed a maximum activity at a temperature of 30 °C and a pH of 6.0 and was stable at temperatures below 30 °C. Its Km and Vmax values were 2.094 mg/mL and 6.982 U/mg, respectively. The cloning strategy used and AgaWH117 isolated in this study will provide information on the saccharification process of marine biomass. This study provides a method to produce l-AHG from agarose by using AgaWH117 without an acid and describes its one-step purification by using Bio-Gel P2 chromatography.

  11. Single-conformation infrared spectra of model peptides in the amide I and amide II regions: experiment-based determination of local mode frequencies and inter-mode coupling.

    Science.gov (United States)

    Buchanan, Evan G; James, William H; Choi, Soo Hyuk; Guo, Li; Gellman, Samuel H; Müller, Christian W; Zwier, Timothy S

    2012-09-07

    Single-conformation infrared spectra in the amide I and amide II regions have been recorded for a total of 34 conformations of three α-peptides, three β-peptides, four α/β-peptides, and one γ-peptide using resonant ion-dip infrared spectroscopy of the jet-cooled, isolated molecules. Assignments based on the amide NH stretch region were in hand, with the amide I/II data providing additional evidence in favor of the assignments. A set of 21 conformations that represent the full range of H-bonded structures were chosen to characterize the conformational dependence of the vibrational frequencies and infrared intensities of the local amide I and amide II modes and their amide I/I and amide II/II coupling constants. Scaled, harmonic calculations at the DFT M05-2X/6-31+G(d) level of theory accurately reproduce the experimental frequencies and infrared intensities in both the amide I and amide II regions. In the amide I region, Hessian reconstruction was used to extract local mode frequencies and amide I/I coupling constants for each conformation. These local amide I frequencies are in excellent agreement with those predicted by DFT calculations on the corresponding (13)C = (18)O isotopologues. In the amide II region, potential energy distribution analysis was combined with the Hessian reconstruction scheme to extract local amide II frequencies and amide II/II coupling constants. The agreement between these local amide II frequencies and those obtained from DFT calculations on the N-D isotopologues is slightly worse than for the corresponding comparison in the amide I region. The local mode frequencies in both regions are dictated by a combination of the direct H-bonding environment and indirect, "backside" H-bonds to the same amide group. More importantly, the sign and magnitude of the inter-amide coupling constants in both the amide I and amide II regions is shown to be characteristic of the size of the H-bonded ring linking the two amide groups. These amide I/I and

  12. Total synthesis of feglymycin based on a linear/convergent hybrid approach using micro-flow amide bond formation

    Science.gov (United States)

    Fuse, Shinichiro; Mifune, Yuto; Nakamura, Hiroyuki; Tanaka, Hiroshi

    2016-11-01

    Feglymycin is a naturally occurring, anti-HIV and antimicrobial 13-mer peptide that includes highly racemizable 3,5-dihydroxyphenylglycines (Dpgs). Here we describe the total synthesis of feglymycin based on a linear/convergent hybrid approach. Our originally developed micro-flow amide bond formation enabled highly racemizable peptide chain elongation based on a linear approach that was previously considered impossible. Our developed approach will enable the practical preparation of biologically active oligopeptides that contain highly racemizable amino acids, which are attractive drug candidates.

  13. New structural motif for carboxylic acid perhydrolases

    OpenAIRE

    Yin, Delu; Purpero, Vince M.; Fujii, Ryota; Jing, Qing; Kazlauskas, Romas J.

    2013-01-01

    Some serine hydrolases also catalyze a promiscuous reaction – reversible perhydrolysis of carboxylic acids to make peroxycarboxylic acids. Five x-ray crystal structures of these carboxylic acid perhydrolases show a proline in the oxyanion loop. Here, we test whether this proline is essential for high perhydrolysis activity using Pseudomonas fluorescens esterase (PFE). The L29P variant of this esterase catalyzes perhydrolysis 43-fold faster (kcat comparison) than wild type. Surprisingly, satur...

  14. An efficient and convenient synthesis of N-substituted amides under heterogeneous condition using Al(HSO4)3 via Ritter reaction

    Indian Academy of Sciences (India)

    Elnaz Karimian; Batool Akhlaghinia; Sara S E Ghodsinia

    2016-03-01

    An efficient and inexpensive synthesis of N-substituted amides from the reaction of aliphatic and aromatic nitriles with various benzylic alcohols (secondary and tertiary) and tert-butyl alcohol by refluxing nitromethane via the Ritter reaction catalyzed by aluminum hydrogen sulfate [Al(HSO4)3] is described. Thecatalyst which is an air-stable, cost-effective solid acid could be readily recycled by filtration and reused four times without any significant loss of its activity.

  15. Chlamydia trachomatis CT771 (nudH) is an asymmetric Ap4A hydrolase

    Science.gov (United States)

    Barta, Michael L.; Lovell, Scott; Sinclair, Amy N.; Battaile, Kevin P.; Hefty, P. Scott

    2014-01-01

    Asymmetric diadenosine 5′,5′″-P1,P4-tetraphosphate (Ap4A) hydrolases are members of the Nudix superfamily that asymmetrically cleave the metabolite Ap4A into ATP and AMP while facilitating homeostasis. The obligate intracellular mammalian pathogen Chlamydia trachomatis possesses a single Nudix family protein, CT771. As pathogens that rely on a host for replication and dissemination typically have one or zero Nudix family proteins, this suggests that CT771 could be critical for chlamydial biology and pathogenesis. We identified orthologs to CT771 within environmental Chlamydiales that share active site residues suggesting a common function. Crystal structures of both apo- and ligand-bound CT771 were determined to 2.6 Å and 1.9 Å resolution, respectively. The structure of CT771 shows a αβα-sandwich motif with many conserved elements lining the putative Nudix active site. Numerous aspects of the ligand-bound CT771 structure mirror those observed in the ligand-bound structure of the Ap4A hydrolase from Caenorhabditis elegans. These structures represent only the second Ap4A hydrolase enzyme member determined from eubacteria and suggest that mammalian and bacterial Ap4A hydrolases might be more similar than previously thought. The aforementioned structural similarities, in tandem with molecular docking, guided the enzymatic characterization of CT771. Together, these studies provide the molecular details for substrate binding and specificity, supporting the analysis that CT771 is an Ap4A hydrolase (nudH). PMID:24354275

  16. Recruitment of Glycosyl Hydrolase Proteins in a Cone Snail Venomous Arsenal: Further Insights into Biomolecular Features of Conus Venoms

    Directory of Open Access Journals (Sweden)

    Philippe Favreau

    2012-01-01

    Full Text Available Cone snail venoms are considered an untapped reservoir of extremely diverse peptides, named conopeptides, displaying a wide array of pharmacological activities. We report here for the first time, the presence of high molecular weight compounds that participate in the envenomation cocktail used by these marine snails. Using a combination of proteomic and transcriptomic approaches, we identified glycosyl hydrolase proteins, of the hyaluronidase type (Hyal, from the dissected and injectable venoms (“injectable venom” stands for the venom variety obtained by milking of the snails. This is in contrast to the “dissected venom”, which was obtained from dissected snails by extraction of the venom glands of a fish-hunting cone snail, Conus consors (Pionoconus clade. The major Hyal isoform, Conohyal-Cn1, is expressed as a mixture of numerous glycosylated proteins in the 50 kDa molecular mass range, as observed in 2D gel and mass spectrometry analyses. Further proteomic analysis and venom duct mRNA sequencing allowed full sequence determination. Additionally, unambiguous segment location of at least three glycosylation sites could be determined, with glycans corresponding to multiple hexose (Hex and N-acetylhexosamine (HexNAc moieties. With respect to other known Hyals, Conohyal-Cn1 clearly belongs to the hydrolase-type of Hyals, with strictly conserved consensus catalytic donor and positioning residues. Potent biological activity of the native Conohyals could be confirmed in degrading hyaluronic acid. A similar Hyal sequence was also found in the venom duct transcriptome of C. adamsonii (Textilia clade, implying a possible widespread recruitment of this enzyme family in fish-hunting cone snail venoms. These results provide the first detailed Hyal sequence characterized from a cone snail venom, and to a larger extent in the Mollusca phylum, thus extending our knowledge on this protein family and its evolutionary selection in marine snail venoms.

  17. Soluble epoxide hydrolase gene deletion improves blood flow and reduces infarct size after cerebral ischemia in reproductively senescent female mice

    Directory of Open Access Journals (Sweden)

    Kristen L Zuloaga

    2015-01-01

    Full Text Available Soluble epoxide hydrolase (sEH, a key enzyme in the metabolism of vasodilatory epoxyeicosatrienoic acids (EETs, is sexually dimorphic, suppressed by estrogen, and contributes to underlying sex differences in cerebral blood flow and injury after cerebral ischemia. We tested the hypothesis that sEH inhibition or gene deletion in reproductively senescent (RS female mice would increase cerebral perfusion and decrease infarct size following stroke. RS (15-18 month old and young (3-4 month old female sEH knockout (sEHKO mice and wild type (WT mice were subjected to 45 min middle cerebral artery occlusion (MCAO with laser Doppler perfusion monitoring. WT mice were treated with vehicle or a sEH inhibitor t-AUCB at the time of reperfusion and every 24hrs thereafter for 3 days. Differences in regional cerebral blood flow were measured in vivo using optical microangiography. Infarct size was measured 3 days after reperfusion. Infarct size and cerebral perfusion 24h after MCAO were not altered by age. Both sEH gene deletion and sEH inhibition increased cortical perfusion 24h after MCAO. Neither sEH gene deletion nor sEH inhibition reduced infarct size in young mice. However, sEH gene deletion, but not sEH inhibition of the hydrolase domain of the enzyme, decreased infarct size in RS mice. Results of these studies show that sEH gene deletion and sEH inhibition enhance cortical perfusion following MCAO and sEH gene deletion reduces damage after ischemia in RS female mice; however this neuroprotection in absent is young mice.

  18. Isolation and Total Synthesis of Stolonines A–C, Unique Taurine Amides from the Australian Marine Tunicate Cnemidocarpa stolonifera

    Directory of Open Access Journals (Sweden)

    Trong D. Tran

    2015-07-01

    Full Text Available Cnemidocarpa stolonifera is an underexplored marine tunicate that only occurs on the tropical to subtropical East Coast of Australia, with only two pyridoacridine compounds reported previously. Qualitative analysis of the lead-like enhanced fractions of C. stolonifera by LC-MS dual electrospray ionization coupled with PDA and ELSD detectors led to the identification of three new natural products, stolonines A–C (1–3, belonging to the taurine amide structure class. Structures of the new compounds were determined by NMR and MS analyses and later verified by total synthesis. This is the first time that the conjugates of taurine with 3-indoleglyoxylic acid, quinoline-2-carboxylic acid and β-carboline-3-carboxylic acid present in stolonines A–C (1–3, respectively, have been reported. An immunofluorescence assay on PC3 cells indicated that compounds 1 and 3 increased cell size, induced mitochondrial texture elongation, and caused apoptosis in PC3 cells.

  19. Isolation and Total Synthesis of Stolonines A-C, Unique Taurine Amides from the Australian Marine Tunicate Cnemidocarpa stolonifera.

    Science.gov (United States)

    Tran, Trong D; Pham, Ngoc B; Ekins, Merrick; Hooper, John N A; Quinn, Ronald J

    2015-07-22

    Cnemidocarpa stolonifera is an underexplored marine tunicate that only occurs on the tropical to subtropical East Coast of Australia, with only two pyridoacridine compounds reported previously. Qualitative analysis of the lead-like enhanced fractions of C. stolonifera by LC-MS dual electrospray ionization coupled with PDA and ELSD detectors led to the identification of three new natural products, stolonines A-C (1-3), belonging to the taurine amide structure class. Structures of the new compounds were determined by NMR and MS analyses and later verified by total synthesis. This is the first time that the conjugates of taurine with 3-indoleglyoxylic acid, quinoline-2-carboxylic acid and β-carboline-3-carboxylic acid present in stolonines A-C (1-3), respectively, have been reported. An immunofluorescence assay on PC3 cells indicated that compounds 1 and 3 increased cell size, induced mitochondrial texture elongation, and caused apoptosis in PC3 cells.

  20. Bioprospecting metagenomics of decaying wood: mining for new glycoside hydrolases

    Energy Technology Data Exchange (ETDEWEB)

    Li L. L.; van der Lelie D.; Taghavi, S.; McCorkle, S. M.; Zhang, Y.-B.; Blewitt, M. G.; Brunecky, R.; Adney, W. S.; Himmel, M. E.; Brumm, P.; Drinkwater, C.; Mead, D. A.; Tringe, S. G.

    2011-08-01

    To efficiently deconstruct recalcitrant plant biomass to fermentable sugars in industrial processes, biocatalysts of higher performance and lower cost are required. The genetic diversity found in the metagenomes of natural microbial biomass decay communities may harbor such enzymes. Our goal was to discover and characterize new glycoside hydrolases (GHases) from microbial biomass decay communities, especially those from unknown or never previously cultivated microorganisms. From the metagenome sequences of an anaerobic microbial community actively decaying poplar biomass, we identified approximately 4,000 GHase homologs. Based on homology to GHase families/activities of interest and the quality of the sequences, candidates were selected for full-length cloning and subsequent expression. As an alternative strategy, a metagenome expression library was constructed and screened for GHase activities. These combined efforts resulted in the cloning of four novel GHases that could be successfully expressed in Escherichia coli. Further characterization showed that two enzymes showed significant activity on p-nitrophenyl-{alpha}-L-arabinofuranoside, one enzyme had significant activity against p-nitrophenyl-{beta}-D-glucopyranoside, and one enzyme showed significant activity against p-nitrophenyl-{beta}-D-xylopyranoside. Enzymes were also tested in the presence of ionic liquids. Metagenomics provides a good resource for mining novel biomass degrading enzymes and for screening of cellulolytic enzyme activities. The four GHases that were cloned may have potential application for deconstruction of biomass pretreated with ionic liquids, as they remain active in the presence of up to 20% ionic liquid (except for 1-ethyl-3-methylimidazolium diethyl phosphate). Alternatively, ionic liquids might be used to immobilize or stabilize these enzymes for minimal solvent processing of biomass.

  1. Bioprospecting metagenomics of decaying wood: mining for new glycoside hydrolases

    Directory of Open Access Journals (Sweden)

    Li Luen-Luen

    2011-08-01

    Full Text Available Abstract Background To efficiently deconstruct recalcitrant plant biomass to fermentable sugars in industrial processes, biocatalysts of higher performance and lower cost are required. The genetic diversity found in the metagenomes of natural microbial biomass decay communities may harbor such enzymes. Our goal was to discover and characterize new glycoside hydrolases (GHases from microbial biomass decay communities, especially those from unknown or never previously cultivated microorganisms. Results From the metagenome sequences of an anaerobic microbial community actively decaying poplar biomass, we identified approximately 4,000 GHase homologs. Based on homology to GHase families/activities of interest and the quality of the sequences, candidates were selected for full-length cloning and subsequent expression. As an alternative strategy, a metagenome expression library was constructed and screened for GHase activities. These combined efforts resulted in the cloning of four novel GHases that could be successfully expressed in Escherichia coli. Further characterization showed that two enzymes showed significant activity on p-nitrophenyl-α-L-arabinofuranoside, one enzyme had significant activity against p-nitrophenyl-β-D-glucopyranoside, and one enzyme showed significant activity against p-nitrophenyl-β-D-xylopyranoside. Enzymes were also tested in the presence of ionic liquids. Conclusions Metagenomics provides a good resource for mining novel biomass degrading enzymes and for screening of cellulolytic enzyme activities. The four GHases that were cloned may have potential application for deconstruction of biomass pretreated with ionic liquids, as they remain active in the presence of up to 20% ionic liquid (except for 1-ethyl-3-methylimidazolium diethyl phosphate. Alternatively, ionic liquids might be used to immobilize or stabilize these enzymes for minimal solvent processing of biomass.

  2. Fabrication and characterization of poly(amide-imides)/TiO₂ nanocomposite gas separation membranes

    OpenAIRE

    1996-01-01

    Nanosized Ti02 rich domains were generated in-situ within poly(amide-imide) (PAl) and 6F-poly(amide-imide) (6FPAl) by a sol-gel process. The composite films showed a high optical transparency. The morphology of the Ti02 rich domains was observed by transmission electron microscopy (TEM). The Ti02 rich domains were well dispersed within the poly(amide-imide) and 6F-poly(amide-imide) matrices and were 5 nm to 50 nm in size. Limited study was also carried out for the fabrication o...

  3. Engineering and introduction of de novo disulphide bridges in organophosphorus hydrolase enzyme for thermostability improvement

    Indian Academy of Sciences (India)

    GHOLAMREZA FARNOOSH; KHOSRO KHAJEH; ALI MOHAMMAD LATIFI; HOSSEIN AGHAMOLLAEI

    2016-12-01

    The organophosphorus hydrolase (OPH) has been used to degrade organophosphorus chemicals, as one of the mostfrequently used decontamination methods. Under chemical and thermal denaturing conditions, the enzyme has beenshown to unfold. To utilize this enzyme in various applications, the thermal stability is of importance. The engineeringof de novo disulphide bridges has been explored as a means to increase the thermal stability of enzymes in the rationalmethod of protein engineering. In this study, Disulphide by Design software, homology modelling and moleculardynamics simulations were used to select appropriate amino acid pairs for the introduction of disulphide bridge toimprove protein thermostability. The thermostability of the wild-type and three selected mutant enzymes wereevaluated by half-life, ΔG inactivation (ΔGi) and structural studies (fluorescence and far-UV CD analysis). Dataanalysis showed that half-life of A204C/T234C and T128C/E153C mutants were increased up to 4 and 24 min,respectively; however, for the G74C/A78C mutant, the half-life was decreased up to 9 min. For the T128C/E124Cmutant, both thermal stability and Catalytic efficiency (kcat) were also increased. The half-life and ΔGi results werecorrelated to the obtained information from structural studies by circular dichroism (CD) spectrometry and extrinsicfluorescence experiments; as rigidity increased in A204C/T2234C and T128C/E153C mutants, half-life and ΔGi alsoincreased. For G74C/A78C mutant, these parameters decreased due to its higher flexibility. The results weresubmitted a strong evidence for the possibility to improve the thermostability of OPH enzyme by introducing adisulphide bridge after bioinformatics design, even though this design would not be always successful.

  4. Gene deficiency and pharmacological inhibition of soluble epoxide hydrolase confers resilience to repeated social defeat stress.

    Science.gov (United States)

    Ren, Qian; Ma, Min; Ishima, Tamaki; Morisseau, Christophe; Yang, Jun; Wagner, Karen M; Zhang, Ji-Chun; Yang, Chun; Yao, Wei; Dong, Chao; Han, Mei; Hammock, Bruce D; Hashimoto, Kenji

    2016-03-29

    Depression is a severe and chronic psychiatric disease, affecting 350 million subjects worldwide. Although multiple antidepressants have been used in the treatment of depressive symptoms, their beneficial effects are limited. The soluble epoxide hydrolase (sEH) plays a key role in the inflammation that is involved in depression. Thus, we examined here the role of sEH in depression. In both inflammation and social defeat stress models of depression, a potent sEH inhibitor, TPPU, displayed rapid antidepressant effects. Expression of sEH protein in the brain from chronically stressed (susceptible) mice was higher than of control mice. Furthermore, expression of sEH protein in postmortem brain samples of patients with psychiatric diseases, including depression, bipolar disorder, and schizophrenia, was higher than controls. This finding suggests that increased sEH levels might be involved in the pathogenesis of certain psychiatric diseases. In support of this hypothesis, pretreatment with TPPU prevented the onset of depression-like behaviors after inflammation or repeated social defeat stress. Moreover, sEH KO mice did not show depression-like behavior after repeated social defeat stress, suggesting stress resilience. The sEH KO mice showed increased brain-derived neurotrophic factor (BDNF) and phosphorylation of its receptor TrkB in the prefrontal cortex, hippocampus, but not nucleus accumbens, suggesting that increased BDNF-TrkB signaling in the prefrontal cortex and hippocampus confer stress resilience. All of these findings suggest that sEH plays a key role in the pathophysiology of depression, and that epoxy fatty acids, their mimics, as well as sEH inhibitors could be potential therapeutic or prophylactic drugs for depression.

  5. Three new amides from Streptomyces sp. H7372

    OpenAIRE

    Cheenpracha, Sarot; Borris,Robert P; Tran,Tammy T.; Jee,Jap Meng; Seow, Heng Fong; Cheah,Hwen-Yee; Ho,Coy Choke; Chang, Leng Chee

    2011-01-01

    Three new amides, methyl phenatate A (1), actiphenamide (2) and actiphenol 1-β-D-glucopyranoside (3), along with thirteen known compounds, were isolated from the organic extract of a fermentation culture of Streptomyces sp. H7372. The structures were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques, and MS analyses. Cycloheximide (6) and cyclo(ΔAla-L-Val) (8) gave a clear zone of inhibition of Ras-Raf-1 interaction in the yeast two-hybrid assay which showed hi...

  6. Identification of nitrogen compounds and amides from spent hydroprocessing catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J.H.K.; Gray, M.R. (University of Alberta, Edmonton, AB (Canada). Dept. of Chemical Engineering)

    1991-06-01

    A spent commercial naphtha hydrotreating catalyst was analyzed to identify compounds which had accumulated on the catalyst surface during its active life. The catalyst was extracted with methylene chloride, methanol and pyridine to remove adsorbed organic material, which was rich in nitrogen and oxygen. A series of quinolones were identified in the methanol extract after enrichment with HCl-modified silica gel adsorption and subsequent silica gel chromatography. Tetra- and hexahydroquinolones with alkyl substituents up to C{sub 3} were identified. Similar amides have been identified in asphaltenes, and are very resistant to hydrogenation. Tetrahydroquinolines and piperidines were detected in the pyridine extract. 36 refs., 8 figs., 2 tabs.

  7. Antifungal activity of natural and synthetic amides from Piper species

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Joaquim V.; Oliveira, Alberto de; Kato, Massuo J., E-mail: majokato@iq.usp.b [Universidade de Sao Paulo (IQ/USP), SP (Brazil). Inst. de Quimica; Raggi, Ludmila; Young, Maria C. [Instituto de Botanica, Sao Paulo, SP (Brazil). Secao de Fisiologia e Bioquimica de Plantas

    2010-07-01

    The antifungal leaves extract from Piper scutifolium was submitted to bioactivity-guided chromatographic separation against Cladosporium cladosporioides and C. sphaerospermum yielding piperine, piperlonguminine and corcovadine as the active principles which displayed a detection limit of 1 {mu}g. Structure-activity relationships were investigated with the preparation of twelve analogs having differences in the number of unsaturations, aromatic ring substituents and in the amide moiety. Analogs having a single double-bond and no substituent in the aromatic ring displayed higher activity, while N,N,-diethyl analogs displayed higher dose-dependent activity. (author)

  8. Synthesis and structures of new helical,nanoscale ferrocenylphenyl amides

    Institute of Scientific and Technical Information of China (English)

    XU Yan; RAN Chunling; WANG Haixian; SONG Maoping

    2007-01-01

    Two novel ferrocenylphenyl-containing amides have been synthesized by reaction of ferrocenylbencarboxylchloride and 1,2-di-(o-aminophenoxy)ethane.A single crystal X-ray analysis shows that compound 3 crystallizes in the triclinic system,space group P-1,and compound 4 crystallizes in orthorhombic system,space group Pca21.There areintramolecular H-bonds in both the compounds,two H-bonds in compound 3 and one in compound 4.The dihedral angels of Cp-ring and phenyl ring range from 3.8° to 20.8°.

  9. WAYS TO OBTAIN AMIDES CONTAINING SALTS 3D-METALS BASED ON TALL OIL ROSIN AND STUDYING THEI INFLUENCE ON THE PROPERTIES OF THE SYSTEM "RUBBER - BRASSED METAL CORD"

    Directory of Open Access Journals (Sweden)

    K. P. Kolnogorov

    2014-01-01

    Full Text Available Summary. This article discusses how to obtain amide-containing salts of 3d-metals based on tall rosin. A scheme of obtaining amide containing salts 3dmetals. The scheme of obtaining amide-containing salts of 3d-metals presented here. Ammonolysis maleopimaric acid was carried out, the technological parameters of the process were identified. Found that the process of ammonolysis affected by the following controlled technological factors: the ratio of the components, the temperature of the reaction medium and the duration of holding ammonolysis. The results of studies of the effect of additives on the received technical and technological properties of the elastomer compositions, adhesion and corrosion resistance rubber-systems are presented. The most efficient promoters are metalcord-rubber adhesion systems for use in the manufacture of tires fitted. Providing the necessary technological properties of manufacturing rubber compounds achieved when using elastomeric compositions consisting of a cobalt salt of amide MTC. Found that necessary to adjust the composition of the vulcanizing system using the synthesized compounds. It was revealed that the elastomeric composition comprising cobalt salt of amide maleated rosin and cobalt naphthenate are less susceptible to oxygen and air at elevated temperature compared to rubber containing salts Mn (II and Cr (III amide MTC. The results of studies of bond strength rubber with steel showed that the adhesive properties of rubber-systems with the test components depend on the dosage and rubber compound. It was determined that the introduction of salts of Co (II, based on amide maleated tall oil rosin at a dosage of 1.5 wt. parts per 100 wt. phr produces indicators adhesion and corrosion properties at the level of those with industrial modifier cobalt naphthenate. The results of research of obtained compounds influence on the technical and technological properties of the elastomer compositions, adhesion and

  10. Murein hydrolase activity of surface layer proteins from Lactobacillus acidophilus against Escherichia coli.

    Science.gov (United States)

    Meng, Jun; Gao, Shu-Ming; Zhang, Qiu-Xiang; Lu, Rong-Rong

    2015-08-01

    The aim of this study was to investigate the murein hydrolase activities of the surface layer proteins (SLPs) from two strains of Lactobacillus acidophilus using zymography. The influence of these hydrolase activities on Escherichia coli ATCC 43893 was also evaluated by analysing their growth curve, cell morphology and physiological state. After the incubation of E. coli with SLPs, growth was inhibited, the number of viable cells was significantly reduced, examination by transmission electron microscopy showed that the cell wall was damaged and flow cytometry results indicated that the majority of the cells were sublethally injured. All of these results suggested that the SLPs of both L. acidophilus strains possessed murein hydrolase activities that were sublethal to E. coli cells.

  11. Inhibiting Inosine Hydrolase and Alanine Racemase to Enhance the Germination of Bacillus anthracis Sterne Spores: Potential Spore Decontamination Strategies

    Science.gov (United States)

    2015-06-19

    2015): << Inhibiting inosine hydrolase and alanine racemase to enhance the germination of Bacillus anthracis Sterne spores: potential spore...inosine hydrolase and alanine racemase to enhance the germination of Bacillus anthracis Sterne spores potential spore decontamination strategies 5a...EASIER, SAFER, and CHEAPER Inducing spore germination should make resulting bacteria much more susceptible to decontamination methods and will be

  12. The putative α/β-hydrolases of Dietzia cinnamea P4 strain as potential enzymes for biocatalytic applications

    NARCIS (Netherlands)

    Procopio da Silva, Luciano; Macrae, Andrew; van Elsas, Jan Dirk; Seldin, Lucy

    2013-01-01

    The draft genome of the soil actinomycete Dietzia cinnamea P4 reveals a versatile group of alpha/beta-hydrolase fold enzymes. Phylogenetic and comparative sequence analyses were used to classify the alpha/beta-hydrolases of strain P4 into six different groups: (i) lipases, (ii) esterases, (iii) epox

  13. Sequential changes of lamellar body hydrolases during ozone-induced alveolar injury and repair

    Energy Technology Data Exchange (ETDEWEB)

    Glew, R.H.; Basu, A.; Shelley, S.A.; Paterson, J.F.; Diven, W.F.; Montgomery, M.R.; Balis, J.U.

    1989-05-01

    Lamellar body hydrolases in acutely damaged and regenerating type II cells were determined using an established rat model with well-defined stages of bronchiolo-alveolar injury and repair. Lamellar bodies were isolated from control and ozone-exposed (3.0 ppm for 8 hours) adult male rats by sucrose density gradient centrifugation and analyzed for their content of six different lysosomal hydrolases. Immediately after 3 ppm ozone exposure (zero-time) there was a significant decrease in specific enzyme activity (units/mg protein) of five lamellar body hydrolases and these activities remained depressed for at least 24 hours after exposure. In addition, total enzyme activity (units/lung) was reduced at zero-time for beta-hexosaminidase and at 24 hours postexposure for alpha-mannosidase and alpha-L-fucosidase. During the reparative and recovery stages (48 to 96 hours) the hydrolases demonstrated variable elevations in both specific activity and total activity (units/lung). Characteristically, beta-hexosaminidase and beta-galactosidase reached supranormal values at 96 hours, whereas alpha-mannosidase remained below normal levels through the recovery stage. Moreover, at 24 to 48 hours the lamellar body fraction demonstrated prominent enzyme depletion relative to the expanding pool of stored surfactant. It is concluded that acute ozone stress initiates the development of hydrolase deficiency within the lamellar bodies of injured and regenerating type II cells. This deficiency state is followed by asynchronous lamellar body hydrolase elevations that reflect distinct patterns of response rather than uniform return to normal condition. The lysosomal enzyme changes of lamellar bodies may be pathogenetically linked to the development of associated alterations in the storage and secretion of surfactant.

  14. Biosynthesis of intestinal microvillar proteins. Intracellular processing of lactase-phlorizin hydrolase

    DEFF Research Database (Denmark)

    Danielsen, E M; Skovbjerg, H; Norén, Ove

    1984-01-01

    The biosynthesis of pig small intestinal lactase-phlorizin hydrolase (EC 3.2.1.23-62) was studied by labelling of organ cultured mucosal explants with [35S]methionine. The earliest detactable form of the enzyme was an intracellular, membrane-bound polypeptide of Mr 225 000, sensitive to endo H...... 000 polypeptide is of the same size as the mature lactase-phlorizin hydrolase and was the only form expressed in the microvillar membrane. Together, these data are indicative of an intracellular proteolytic cleavage during transport. The presence of leupeptin during labelling prevented the appearance...

  15. Diversity of glycosyl hydrolase enzymes from metagenome and their application in food industry.

    Science.gov (United States)

    Sathya, T A; Khan, Mahejibin

    2014-11-01

    Traditional use of enzymes for food processing and production of food ingredients resulted in fast-growing enzyme industries world over. The advances in technologies gave rise to exploring newer enzymes and/or modified enzymes for specific application. Search for novel enzymes that can augment catalytic efficiency and advances in molecular biology techniques including sequencing has targeted microbial diversity through metagenomic approaches for sourcing enzymes from difficult to culture organisms. Such mining studies have received more attention in characterizing hydrolases, their prevalence, broad substrate specificities, stability, and independence of cofactors. The focus on glycosyl hydrolases from metagenome for their application in food sector is reviewed.

  16. NCBI nr-aa BLAST: CBRC-MEUG-01-1177 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available ucture Analysis Of A PhenhexylOXAZOLECARBOXYPYRIDINE ALPHA-Ketoheterocycle Inhibitor Bound To A Humanized Varian...is Of A PhenhexylOXAZOLECARBOXYPYRIDINE ALPHA-Ketoheterocycle Inhibitor Bound To A Humanized Variant Of Fatt...LPHA-Ketoheterocycle Inhibitor Bound To A Humanized Variant Of Fatty Acid Amide Hydrolase pdb|3K83|B Chain B...cycle Inhibitor Bound To A Humanized Variant Of Fatty Acid Amide Hydrolase pdb|3K84|A Chain A, Crystal Struc...ture Analysis Of A OleylOXADIAZOLEPYRIDINE Inhibitor Bound To A Humanized Variant Of Fatty Acid Amide Hydrol

  17. Mutually exclusive distribution of the sap and eag S-layer genes and the lytB/lytA cell wall hydrolase genes in Bacillus thuringiensis.

    Science.gov (United States)

    Soufiane, Brahim; Sirois, Marc; Côté, Jean-Charles

    2011-10-01

    Recently, two Bacillus thuringiensis strains were reported to synthesize parasporal inclusion bodies made not of the expected crystal (Cry) proteins but rather of the surface layer proteins (SLP) Sap (encoded by sap) and EA1 (encoded by eag), respectively. Whether the presence of the sap and eag genes is restricted to these two B. thuringiensis strains or ubiquitous in B. thuringiensis is unknown. We report here the distribution of the sap and eag genes in B. thuringiensis. Strains in the Bacillus cereus group were added for comparison purposes. We show that sap and eag are either present in tandem in 35% of the B. thuringiensis strains analysed and absent in 65% of the strains. When absent, a different tandem, the lytB/lytA cell wall hydrolase genes, is present. The distribution of the sap and eag S-layer and the lytB/lytA cell wall hydrolase genes is not species-specific in B. thuringiensis, B. cereus and Bacillus weihenstephanensis. Bacillus anthracis and Bacillus mycoides harbor sap and eag but not lytB/lytA. The sap, eag and lytB/lytA genes were absent in Bacillus pseudomycoides. Clearly, the distribution of the sap and eag S-layer and the lytB/lytA cell wall hydrolase genes in B. thuringiensis and in the Bacillus cereus group is mutually exclusive. We also showed that two genes involved in cell wall metabolism, csaA and csaB, are present not only upstream of the sap and eag S-layer genes, but also upstream of the lytB/lytA tandem in strains where sap and eag are absent. Bootstrapped neighbor-joining trees were inferred from the translated amino acid sequences of sap, eag and the tandem lytB/lytA, respectively.

  18. Temperature dependence of C-terminal carboxylic group IR absorptions in the amide I' region.

    Science.gov (United States)

    Anderson, Benjamin A; Literati, Alex; Ball, Borden; Kubelka, Jan

    2015-01-01

    Studies of structural changes in peptides and proteins using IR spectroscopy often rely on subtle changes in the amide I' band as a function of temperature. However, these changes can be obscured by the overlap with other absorptions, namely the side-chain and terminal carboxylic groups. The former were the subject of our previous report (Anderson et al., 2014). In this paper we investigate the IR spectra of the asymmetric stretch of α-carboxylic groups for amino acids representing all major types (Gly, Ala, Val, Leu, Ser, Thr, Asp, Glu, Lys, Asn, His, Trp, Pro) as well as the C-terminal groups of three dipeptides (Gly-Gly, Gly-Ala, Ala-Gly) in D₂O at neutral pH. Experimental temperature dependent IR spectra were analyzed by fitting of both symmetric and asymmetric pseudo-Voigt functions. Qualitatively the spectra exhibit shifts to higher frequency, loss in intensity and narrowing with increased temperature, similar to that observed previously for the side-chain carboxylic groups of Asp. The observed dependence of the band parameters (frequency, intensity, width and shape) on temperature is in all cases linear: simple linear regression is therefore used to describe the spectral changes. The spectral parameters vary between individual amino acids and show systematic differences between the free amino acids and dipeptides, particularly in the absolute peak frequencies, but the temperature variations are comparable. The relative variations between the dipeptide spectral parameters are most sensitive to the C-terminal amino acid, and follow the trends observed in the free amino acid spectra. General rules for modeling the α-carboxylic IR absorption bands in peptides and proteins as the function of temperature are proposed.

  19. Temperature dependence of C-terminal carboxylic group IR absorptions in the amide I‧ region

    Science.gov (United States)

    Anderson, Benjamin A.; Literati, Alex; Ball, Borden; Kubelka, Jan

    2015-01-01

    Studies of structural changes in peptides and proteins using IR spectroscopy often rely on subtle changes in the amide I‧ band as a function of temperature. However, these changes can be obscured by the overlap with other absorptions, namely the side-chain and terminal carboxylic groups. The former were the subject of our previous report (Anderson et al., 2014). In this paper we investigate the IR spectra of the asymmetric stretch of α-carboxylic groups for amino acids representing all major types (Gly, Ala, Val, Leu, Ser, Thr, Asp, Glu, Lys, Asn, His, Trp, Pro) as well as the C-terminal groups of three dipeptides (Gly-Gly, Gly-Ala, Ala-Gly) in D2O at neutral pH. Experimental temperature dependent IR spectra were analyzed by fitting of both symmetric and asymmetric pseudo-Voigt functions. Qualitatively the spectra exhibit shifts to higher frequency, loss in intensity and narrowing with increased temperature, similar to that observed previously for the side-chain carboxylic groups of Asp. The observed dependence of the band parameters (frequency, intensity, width and shape) on temperature is in all cases linear: simple linear regression is therefore used to describe the spectral changes. The spectral parameters vary between individual amino acids and show systematic differences between the free amino acids and dipeptides, particularly in the absolute peak frequencies, but the temperature variations are comparable. The relative variations between the dipeptide spectral parameters are most sensitive to the C-terminal amino acid, and follow the trends observed in the free amino acid spectra. General rules for modeling the α-carboxylic IR absorption bands in peptides and proteins as the function of temperature are proposed.

  20. Use of enzyme inhibitors to evaluate the conversion pathways of ester and amide prodrugs: a case study example with the prodrug ceftobiprole medocaril.

    Science.gov (United States)

    Eichenbaum, Gary; Skibbe, Jennifer; Parkinson, Andrew; Johnson, Mark D; Baumgardner, Dawn; Ogilvie, Brian; Usuki, Etsuko; Tonelli, Fred; Holsapple, Jeff; Schmitt-Hoffmann, Anne

    2012-03-01

    An approach was developed that uses enzyme inhibitors to support the assessment of the pathways that are responsible for the conversion of intravenously administered ester and amide prodrugs in different biological matrices. The methodology was applied to ceftobiprole medocaril (BAL5788), the prodrug of the cephalosporin antibiotic, ceftobiprole. The prodrug was incubated in plasma, postmitochondrial supernatant fractions from human liver (impaired and nonimpaired), kidney, and intestine as well as erythrocytes, in the presence and absence of different enzyme inhibitors (acetylcholinesterase, pseudocholinesterase, retinyl palmitoyl hydrolase, serine esterases, amidases, and cholinesterase). Hydrolysis was rapid, extensive, and not dependent on the presence of β-nicotinamide-adenine dinucleotide phosphate (reduced form) in all matrices tested, suggesting the involvement of carboxylesterases but not P450 enzymes. Hydrolysis in healthy human plasma was rapid and complete and only partially inhibited in the presence of paraoxonase inhibitors or in liver from hepatic impaired patients, suggesting involvement of nonparaoxonase pathways. The results demonstrate the utility of this approach in confirming the presence of multiple conversion pathways of intravenously administered prodrugs and in the case of BAL5788 demonstrated that this prodrug is unlikely to be affected by genetic polymorphisms, drug interactions, or other environmental factors that might inhibit or induce the enzymes involved in its conversion.