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Sample records for serine glycine alanine

  1. A Clostridium difficile alanine racemase affects spore germination and accommodates serine as a substrate.

    Science.gov (United States)

    Shrestha, Ritu; Lockless, Steve W; Sorg, Joseph A

    2017-06-23

    Clostridium difficile has become one of the most common bacterial pathogens in hospital-acquired infections in the United States. Although C. difficile is strictly anaerobic, it survives in aerobic environments and transmits between hosts via spores. C. difficile spore germination is triggered in response to certain bile acids and glycine. Although glycine is the most effective co-germinant, other amino acids can substitute with varying efficiencies. Of these, l-alanine is an effective co-germinant and is also a germinant for most bacterial spores. Many endospore-forming bacteria embed alanine racemases into their spore coats, and these enzymes are thought to convert the l-alanine germinant into d-alanine, a spore germination inhibitor. Although the C. difficile Alr2 racemase is the sixth most highly expressed gene during C. difficile spore formation, a previous study reported that Alr2 has little to no role in germination of C. difficile spores in rich medium. Here, we hypothesized that Alr2 could affect C. difficile l-alanine-induced spore germination in a defined medium. We found that alr2 mutant spores more readily germinate in response to l-alanine as a co-germinant. Surprisingly, d-alanine also functioned as a co-germinant. Moreover, we found that Alr2 could interconvert l- and d-serine and that Alr2 bound to l- and d-serine with ∼2-fold weaker affinity to that of l- and d-alanine. Finally, we demonstrate that l- and d-serine are also co-germinants for C. difficile spores. These results suggest that C. difficile spores can respond to a diverse set of amino acid co-germinants and reveal that Alr2 can accommodate serine as a substrate. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Glycine serine interconversion in the rooster

    International Nuclear Information System (INIS)

    Sugahara, Michihiro; Kandatsu, Makoto

    1976-01-01

    Serine was isolated by the column chromatography from the hydrolyzates of proteins of the serum, the liver and the pectoral muscle which were obtained from the roosters fed a diet containing 2- 14 C glycine for 16 - 17 days. The carbon chain of serine was cut off by treating with sodium periodate. The specific activity of each carbon (as barium carbonate) was estimated. Carboxyl carbon had little radioactivity. The specific activity of hydroxymethyl carbon was 10 - 19% of that of methylene carbon. Glycine isolated from the same hydrolyzates was degraded by ninhydrin oxidation. Formaldehyde produced from 2-C was oxidized to carbon dioxide by treating with mercuric chloride. Carboxyl carbon had little radioactivity. The specific activities of 2-C of glycine and 2-C of serine in the same tissue protein were compared. The ratio of serine 2-C/glycine 2-C was between 0.7 - 1.5. These results seem to indicate that glycine directly converts to serine in the rooster. The quantitative significance of the pathways of glycine (serine) biosynthesis is discussed. (auth.)

  3. Thermodynamics of the ternary systems: (water + glycine, L-alanine and L-serine + di-ammonium hydrogen citrate) from volumetric, compressibility, and (vapour + liquid) equilibria measurements

    International Nuclear Information System (INIS)

    Sadeghi, Rahmat; Gholamireza, Afsaneh

    2011-01-01

    The apparent molar volumes and isentropic compressibility of glycine, L-alanine and L-serine in water and in aqueous solutions of (0.500 and 1.00) mol . kg -1 di-ammonium hydrogen citrate {(NH 4 ) 2 HCit} and those of (NH 4 ) 2 HCit in water have been obtained over the (288.15 to 313.15) K temperature range at 5 K intervals at atmospheric pressure from measurements of density and ultrasonic velocity. The apparent molar volume and isentropic compressibility values at infinite dilution of the investigated amino acids have been obtained and their variations with temperature and their transfer properties from water to aqueous solutions of (NH 4 ) 2 HCit have also been obtained. The results have been interpreted in terms of the hydration of the amino acids. In the second part of this work, water activity measurements by the isopiestic method have been carried out on the aqueous solutions of {glycine + (NH 4 ) 2 HCit}, {alanine + (NH 4 ) 2 HCit}, and {serine + (NH 4 ) 2 HCit} at T = 298.15 K at atmospheric pressure. From these measurements, values of vapour pressure, osmotic coefficient, activity coefficient and Gibbs free energy were obtained. The effect of the type of amino acids on the (vapour + liquid) equilibrium of the systems investigated has been studied. The experimental water activities have been correlated successfully with the segment-based local composition Wilson model. Furthermore, the thermodynamic behaviour of the ternary solutions investigated has been studied by using the semi-ideal hydration model and the linear concentration relations have been tested by comparing with the isopiestic measurements for the studied systems at T = 298.15 K.

  4. Thermodynamics of the ternary systems: (water + glycine, L-alanine and L-serine + di-ammonium hydrogen citrate) from volumetric, compressibility, and (vapour + liquid) equilibria measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, Rahmat, E-mail: rahsadeghi@yahoo.co [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Gholamireza, Afsaneh [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

    2011-02-15

    The apparent molar volumes and isentropic compressibility of glycine, L-alanine and L-serine in water and in aqueous solutions of (0.500 and 1.00) mol . kg{sup -1} di-ammonium hydrogen citrate {l_brace}(NH{sub 4}){sub 2}HCit{r_brace} and those of (NH{sub 4}){sub 2}HCit in water have been obtained over the (288.15 to 313.15) K temperature range at 5 K intervals at atmospheric pressure from measurements of density and ultrasonic velocity. The apparent molar volume and isentropic compressibility values at infinite dilution of the investigated amino acids have been obtained and their variations with temperature and their transfer properties from water to aqueous solutions of (NH{sub 4}){sub 2}HCit have also been obtained. The results have been interpreted in terms of the hydration of the amino acids. In the second part of this work, water activity measurements by the isopiestic method have been carried out on the aqueous solutions of {l_brace}glycine + (NH{sub 4}){sub 2}HCit{r_brace}, {l_brace}alanine + (NH{sub 4}){sub 2}HCit{r_brace}, and {l_brace}serine + (NH{sub 4}){sub 2}HCit{r_brace} at T = 298.15 K at atmospheric pressure. From these measurements, values of vapour pressure, osmotic coefficient, activity coefficient and Gibbs free energy were obtained. The effect of the type of amino acids on the (vapour + liquid) equilibrium of the systems investigated has been studied. The experimental water activities have been correlated successfully with the segment-based local composition Wilson model. Furthermore, the thermodynamic behaviour of the ternary solutions investigated has been studied by using the semi-ideal hydration model and the linear concentration relations have been tested by comparing with the isopiestic measurements for the studied systems at T = 298.15 K.

  5. D-Serine and Glycine Differentially Control Neurotransmission during Visual Cortex Critical Period.

    Directory of Open Access Journals (Sweden)

    Claire N J Meunier

    Full Text Available N-methyl-D-aspartate receptors (NMDARs play a central role in synaptic plasticity. Their activation requires the binding of both glutamate and d-serine or glycine as co-agonist. The prevalence of either co-agonist on NMDA-receptor function differs between brain regions and remains undetermined in the visual cortex (VC at the critical period of postnatal development. Here, we therefore investigated the regulatory role that d-serine and/or glycine may exert on NMDARs function and on synaptic plasticity in the rat VC layer 5 pyramidal neurons of young rats. Using selective enzymatic depletion of d-serine or glycine, we demonstrate that d-serine and not glycine is the endogenous co-agonist of synaptic NMDARs required for the induction and expression of Long Term Potentiation (LTP at both excitatory and inhibitory synapses. Glycine on the other hand is not involved in synaptic efficacy per se but regulates excitatory and inhibitory neurotransmission by activating strychnine-sensitive glycine receptors, then producing a shunting inhibition that controls neuronal gain and results in a depression of synaptic inputs at the somatic level after dendritic integration. In conclusion, we describe for the first time that in the VC both D-serine and glycine differentially regulate somatic depolarization through the activation of distinct synaptic and extrasynaptic receptors.

  6. Volumetric property of glycine, L-serine, L-alanine and L-proline in aqueous solutions of 1-phenylpiperazinium tetrafluoroborate

    International Nuclear Information System (INIS)

    Xie, Hujun; Zhao, Lijiang; Liu, Chengcheng; Cao, Yifan; Lu, Xiaoxing; Lei, Qunfang; Fang, Wenjun

    2016-01-01

    Highlights: • Volumetric property of four amino acids in aqueous solutions of [Phpi][BF_4] were measured. • The standard partial molar volume, transparent partial molar volume and hydration number were calculated. • [Phpi][BF_4] interacts strongly with four kinds of amino acids. • Hydrophilic–hydrophobic and hydrophobic–hydrophobic interactions play the dominant roles in ternary systems. • The ternary systems are generated via multiple hydrogen bond interactions. - Abstract: The densities of aqueous solutions of glycine, L-serine, L-alanine, L-proline with the ionic liquid (IL), 1-phenylpiperazinium tetrafluoroborate ([Phpi][BF_4]) at the IL concentrations of (0.025, 0.055 and 0.100) mol·kg"−"1 have been measured at the temperatures of (298.15, 303.15 and 308.15) K. On the basis of the experimental results, the apparent molar volume (V_Φ), standard partial molar volume (V_Φ"0), transfer partial molar volume (Δ_t_rV_Φ"0) and hydration number (n_H) have been calculated. The hydrophilic–hydrophilic, hydrophobic–hydrophilic and hydrophobic–hydrophobic interactions are involved in the studied systems of {[Phpi][BF_4] + amino acids + H_2O. These volumetric parameters can help to understand the mixing effects and other complex biological processes between amino acids and ionic liquid aqueous solution.

  7. ald of Mycobacterium tuberculosis Encodes both the Alanine Dehydrogenase and the Putative Glycine Dehydrogenase

    Science.gov (United States)

    Giffin, Michelle M.; Modesti, Lucia; Raab, Ronald W.; Wayne, Lawrence G.

    2012-01-01

    The putative glycine dehydrogenase of Mycobacterium tuberculosis catalyzes the reductive amination of glyoxylate to glycine but not the reverse reaction. The enzyme was purified and identified as the previously characterized alanine dehydrogenase. The Ald enzyme was expressed in Escherichia coli and had both pyruvate and glyoxylate aminating activities. The gene, ald, was inactivated in M. tuberculosis, which resulted in the loss of all activities. Both enzyme activities were found associated with the cell and were not detected in the extracellular filtrate. By using an anti-Ald antibody, the protein was localized to the cell membrane, with a smaller fraction in the cytosol. None was detected in the extracellular medium. The ald knockout strain grew without alanine or glycine and was able to utilize glycine but not alanine as a nitrogen source. Transcription of ald was induced when alanine was the sole nitrogen source, and higher levels of Ald enzyme were measured. Ald is proposed to have several functions, including ammonium incorporation and alanine breakdown. PMID:22210765

  8. Unlike pregnant adult women, pregnant adolescent girls cannot maintain glycine flux during late pregnancy because of decreased synthesis from serine.

    Science.gov (United States)

    Hsu, Jean W; Thame, Minerva M; Gibson, Raquel; Baker, Tameka M; Tang, Grace J; Chacko, Shaji K; Jackson, Alan A; Jahoor, Farook

    2016-03-14

    During pregnancy, glycine and serine become more important because they are the primary suppliers of methyl groups for the synthesis of fetal DNA, and more glycine is required for fetal collagen synthesis as pregnancy progresses. In an earlier study, we reported that glycine flux decreased by 39% from the first to the third trimester in pregnant adolescent girls. As serine is a primary precursor for glycine synthesis, the objective of this study was to measure and compare glycine and serine fluxes and inter-conversions in pregnant adolescent girls and adult women in the first and third trimesters. Measurements were made after an overnight fast by continuous intravenous infusions of 2H2-glycine and 15N-serine in eleven adolescent girls (17·4 (se 0·1) years of age) and in ten adult women (25·8 (se 0·5) years of age) for 4 h. Adolescent girls had significantly slower glycine flux and they made less glycine from serine in the third (Padolescent girls (P=0·04) and was significantly associated with third trimester glycine flux. These findings suggest that the pregnant adolescent cannot maintain glycine flux in late pregnancy compared with early pregnancy because of decreased synthesis from serine. It is possible that the inability to maintain glycine synthesis makes her fetus vulnerable to impaired cartilage synthesis, and thus linear growth.

  9. Enzymatic properties of the glycine D-alanine [corrected] aminopeptidase of Aspergillus oryzae and its activity profiles in liquid-cultured mycelia and solid-state rice culture (rice koji).

    Science.gov (United States)

    Marui, Junichiro; Matsushita-Morita, Mayumi; Tada, Sawaki; Hattori, Ryota; Suzuki, Satoshi; Amano, Hitoshi; Ishida, Hiroki; Yamagata, Youhei; Takeuchi, Michio; Kusumoto, Ken-Ichi

    2012-01-01

    The gdaA gene encoding S12 family glycine-D-alanine aminopeptidase (GdaA) was found in the industrial fungus Aspergillus oryzae. GdaA shares 43% amino acid sequence identity with the D-aminopeptidase of the Gram-negative bacterium Ochrobactrum anthropi. GdaA purified from an A. oryzae gdaA-overexpressing strain exhibited high D-stereospecificity and efficiently released N-terminal glycine and D-alanine of substrates in a highly specific manner. The optimum pH and temperature were 8 to 9 and 40°C, respectively. This enzyme was stable under alkaline conditions at pH 8 to 11 and relatively resistant to acidic conditions until pH 5.0. The chelating reagent EDTA, serine protease inhibitors such as AEBSF, benzamidine, TPCK, and TLCK, and the thiol enzyme inhibitor PCMB inhibited the enzyme. The aminopeptidase inhibitor bestatin did not affect the activity. GdaA was largely responsible for intracellular glycine and D-alanine aminopeptidase activities in A. oryzae during stationary-phase growth in liquid media. In addition, the activity increased in response to the depletion of nitrogen or carbon sources in the growth media, although the GdaA-independent glycine aminopeptidase activity highly increased simultaneously. Aminopeptidases of A. oryzae attract attention because the enzymatic release of a variety of amino acids and peptides is important for the enhancement of the palatability of fermented foods. GdaA activity was found in extracts of a solid-state rice culture of A. oryzae (rice koji), which is widely used as a starter culture for Japanese traditional fermented foods, and was largely responsible for the glycine and D-alanine aminopeptidase activity detected at a pH range of 6 to 9.

  10. Serine and alanine racemase activities of VanT: a protein necessary for vancomycin resistance in Enterococcus gallinarum BM4174.

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    Arias, C A; Weisner, J; Blackburn, J M; Reynolds, P E

    2000-07-01

    Vancomycin resistance in Enterococcus gallinarum results from the production of UDP-MurNAc-pentapeptide[D-Ser]. VanT, a membrane-bound serine racemase, is one of three proteins essential for this resistance. To investigate the selectivity of racemization of L-Ser or L-Ala by VanT, a strain of Escherichia coli TKL-10 that requires D-Ala for growth at 42 degrees C was used as host for transformation experiments using plasmids containing the full-length vanT from Ent. gallinarum or the alanine racemase gene (alr) of Bacillus stearothermophilus: both plasmids were able to complement E. coli TKL-10 at 42 degrees C. No alanine or serine racemase activities were detected in the host strain E. coli TKL-10 grown at 30, 34 or 37 degrees C. Serine and alanine racemase activities were found almost exclusively (96%) in the membrane fraction of E. coli TKL-10/pCA4(vanT): the alanine racemase activity of VanT was 14% of the serine racemase activity in both E. coli TKL-10/pCA4(vanT) and E. coli XL-1 Blue/pCA4(vanT). Alanine racemase activity was present mainly (95%) in the cytoplasmic fraction of E. coli TKL-10/pJW40(alr), with a trace (1.6%) of serine racemase activity. Additionally, DNA encoding the soluble domain of VanT was cloned and expressed in E. coli M15 as a His-tagged polypeptide and purified: this polypeptide also exhibited both serine and alanine racemase activities; the latter was approximately 18% of the serine racemase activity, similar to that of the full-length, membrane-bound enzyme. N-terminal sequencing of the purified His-tagged polypeptide revealed a single amino acid sequence, indicating that the formation of heterodimers between subunits of His-tagged C-VanT and endogenous alanine racemases from E. coli was unlikely. The authors conclude that the membrane-bound serine racemase VanT also has alanine racemase activity but is able to racemize serine more efficiently than alanine, and that the cytoplasmic domain is responsible for the racemase activity.

  11. Partial molar volumes of L-alanine, DL-serine, DL-threonine, L-histidine, glycine, and glycylglycine in water, NaCl, and DMSO aqueous solutions at T 298.15 K

    International Nuclear Information System (INIS)

    Yuan Quan; Li Zhifen; Wang Baohuai

    2006-01-01

    The apparent molar volumes of L-alanine, DL-serine, DL-threonine, L-histidine, glycine, and glycylglycine in water and in the aqueous solutions of NaCl and DMSO with various concentrations at T = 298.15 K have been measured by the precise vibrating-tube digital densimeter. The calculated partial molar volumes at infinite dilution have been used to obtain corresponding transfer volumes from water to various solutions. The experimental results show that the standard partial molar volumes of the above amino acids and peptide at the dilute DMSO aqueous solutions are very close to those in water. However, the volumes show several types of variations with the increase of the concentrations of DMSO due to different types of side chain of amino acids, which should be discussed specifically. The NaCl changes considerably the infinite dilution standard partial molar volumes of the above amino acids and peptide in the aqueous solutions. The infinite dilution standard partial molar volumes of the each amino acids and peptide increase with the concentrations of NaCl. The experimental results have been rationalized by a cosphere overlap model

  12. Incorporation of glycine and serine into sporulating cells of Bacillus subtilis

    International Nuclear Information System (INIS)

    Mitani, Takahiko; Kadota, Hajime

    1976-01-01

    The changes during growth and sporulation in activities of cells of Bacillus subtilis to incorporate various amino acids were investigated with wild-type strain and its asporogenous mutant. In the case of wild type strain the uptake of valine, phenylalanine, and proline was largest during the logarithmic growth period. The uptake of these amino acids decreased rapidly during the early stationary phase. The uptake of valine and cysteine increased again to some extent just prior to the forespore stage. The uptake of glycine and serine, however, was largest at the forespore stage at which the formation of spore coat took place. From these observed phenomena it was assumed that the remarkable incorporation of glycine and serine into the wild type strain during sporulation was closely related to the formation of spore coat. (auth.)

  13. Purification, characterization and gene cloning of thermostable O-acetyl-L-serine sulfhydrylase forming β-cyano-L-alanine

    International Nuclear Information System (INIS)

    Omura, Hironori; Yoshida, Toyokazu; Nagasawa, Toru; Kobayashi, Michihiko; Shimizu, Sakayu

    2003-01-01

    A thermophilic and cyanide ion-tolerant bacterium, Bacillus stearothermophilus CN3 isolated from a hot spring in Japan, was found to produce thermostable β-cyano-L-alanine synthase. The enzyme catalyzes the synthesis of β-cyano-L-alanine from O-acetyl-L-serine and cyanide ions. The purified enzyme has a molecular mass of approximately 70 kDa and consists of two identical sub-units. It was stable in the pH range of 6.0 to 10.0 and up to 70degC. The enzyme also catalyzes the synthesis of various β-substituted-L-alanine derivatives from O-acetyl-L-serine and nucleophilic reagents. The gene encoding the β-cyano-L-alanine synthase was isolated from B. stearothermophilus CN3. Sequence homology analysis revealed that the β-cyano-L-alanine synthase of the bacterium is O-acetyl-L-serine sulfhydrylase. A recombinant plasmid, constructed by ligation of the cloned gene and an expression vector, pKK223-3, was introduced into E. coli JM109. The transformed E. coli cells overexpressed β-cyano-L-alanine synthase. Heat stable β-cyano-L-alanine synthase can be applied to the synthesis of [4- 11 C]L-2,4-diaminobutyric acid as a tracer for positron emission tomography. (author)

  14. Purification, characterization and gene cloning of thermostable O-acetyl-L-serine sulfhydrylase forming {beta}-cyano-L-alanine

    Energy Technology Data Exchange (ETDEWEB)

    Omura, Hironori; Yoshida, Toyokazu; Nagasawa, Toru [Gifu Univ. (Japan). Dept. of Biomolecular Science; Kuroda, Masako [Ikeda Food Research Co., Ltd., Fukuyama, Hiroshima (Japan); Kobayashi, Michihiko; Shimizu, Sakayu [Kyoto Univ. (Japan). Agricultural Sciences

    2003-10-01

    A thermophilic and cyanide ion-tolerant bacterium, Bacillus stearothermophilus CN3 isolated from a hot spring in Japan, was found to produce thermostable {beta}-cyano-L-alanine synthase. The enzyme catalyzes the synthesis of {beta}-cyano-L-alanine from O-acetyl-L-serine and cyanide ions. The purified enzyme has a molecular mass of approximately 70 kDa and consists of two identical sub-units. It was stable in the pH range of 6.0 to 10.0 and up to 70degC. The enzyme also catalyzes the synthesis of various {beta}-substituted-L-alanine derivatives from O-acetyl-L-serine and nucleophilic reagents. The gene encoding the {beta}-cyano-L-alanine synthase was isolated from B. stearothermophilus CN3. Sequence homology analysis revealed that the {beta}-cyano-L-alanine synthase of the bacterium is O-acetyl-L-serine sulfhydrylase. A recombinant plasmid, constructed by ligation of the cloned gene and an expression vector, pKK223-3, was introduced into E. coli JM109. The transformed E. coli cells overexpressed {beta}-cyano-L-alanine synthase. Heat stable {beta}-cyano-L-alanine synthase can be applied to the synthesis of [4-{sup 11}C]L-2,4-diaminobutyric acid as a tracer for positron emission tomography. (author)

  15. Survivability and reactivity of glycine and alanine in early oceans: effects of meteorite impacts.

    Science.gov (United States)

    Umeda, Yuhei; Fukunaga, Nao; Sekine, Toshimori; Furukawa, Yoshihiro; Kakegawa, Takeshi; Kobayashi, Takamichi; Nakazawa, Hiromoto

    2016-01-01

    Prebiotic oceans might have contained abundant amino acids, and were subjected to meteorite impacts, especially during the late heavy bombardment. It is so far unknown how meteorite impacts affected amino acids in the early oceans. Impact experiments were performed under the conditions where glycine was synthesized from carbon, ammonia, and water, using aqueous solutions containing (13)C-labeled glycine and alanine. Selected amino acids and amines in samples were analyzed with liquid chromatography-mass spectrometry (LC/MS). In particular, the (13)C-labeled reaction products were analyzed to distinguish between run products and contaminants. The results revealed that both amino acids survived partially in the early ocean through meteorite impacts, that part of glycine changed into alanine, and that large amounts of methylamine and ethylamine were formed. Fast decarboxylation was confirmed to occur during such impact processes. Furthermore, the formation of n-butylamine, detected only in the samples recovered from the solutions with additional nitrogen and carbon sources of ammonia and benzene, suggests that chemical reactions to form new biomolecules can proceed through marine impacts. Methylamine and ethylamine from glycine and alanine increased considerably in the presence of hematite rather than olivine under similar impact conditions. These results also suggest that amino acids present in early oceans can contribute further to impact-induced reactions, implying that impact energy plays a potential role in the prebiotic formation of various biomolecules, although the reactions are complicated and depend upon the chemical environments as well.

  16. Influence of high glycine diets on the activity of glycine-catabolizing enzymes and on glycine catabolism in rats

    International Nuclear Information System (INIS)

    Petzke, K.J.; Albrecht, V.; Przybilski, H.

    1986-01-01

    Male albino rats were adapted to isocaloric purified diets that differed mainly in their glycine and casein contents. Controls received a 30% casein diet. In experimental diets gelatin or gelatin hydrolysate was substituted for half of the 30% casein. An additional group was fed a glycine-supplemented diet, which corresponded in glycine level to the gelatin diet but in which the protein level was nearly the same as that of the casein control diet. Another group received a 15% casein diet. Rat liver glycine cleavage system, serine hydroxymethyltransferase and serine dehydratase activities were measured. 14 CO 2 production from the catabolism of 14 C-labeled glycine was measured in vivo and in vitro (from isolated hepatocytes). Serine dehydratase and glycine cleavage system activities were higher in animals fed 30% casein diets than in those fed 15% casein diets. Serine hydroxymethyltransferase activity of the cytosolic and mitochondrial fractions was highest when a high glycine diet (glycine administered as pure, protein bound in gelatin or peptide bound in gelatin hydrolysate) was fed. 14 CO 2 formation from [1- 14 C]- and [2- 14 C]glycine both in vivo and in isolated hepatocytes was higher when a high glycine diet was fed than when a casein diet was fed. These results suggest that glycine catabolism is dependent on and adaptable to the glycine content of the diet. Serine hydroxymethyltransferase appears to play a major role in the regulation of glycine degradation via serine and pyruvate

  17. Hydrophobic radical influence on structure and vibration spectra of zwitter-ionic forms of glycine and alanine in condensed state

    International Nuclear Information System (INIS)

    Ten, G.N.; Kadrov, D.M.; Baranov, V.I.

    2014-01-01

    Structure and vibrational spectra of the zwitter-ionic forms of glycine and alanine in water solution and solid state have been calculated in the B3LYP/6-311++G(d,p) approximation. The environment influence has been taken into account by two methods: the self-consistent reaction field (SCRF) method and one of modeling the glycine and alanine complexes with molecules of water. The structure, energy and spectral properties have been determined which allow establishing an influence of the hydrophobic radical on the glycine and alanine ability to form the hydrogen bonds. It is shown by comparison with experiment that for the calculation of vibrational (IR and Raman) spectra of the zwitter-ionic forms of glycine and alanine in the condensed states they must be surrounded with three molecules of water, one of which is located between the N + H 3 and COO - ionic groups. The value of energy necessary to form the Ala complexes with water compared to Gly ones is 56.47 and 12.55 kcal/mol higher in the case of the complex formation with 1and 3 molecules of water, respectively, located between bipolar groups. (authors)

  18. Revision of standard molar enthalpies of formation of glycine and L-alanine in the gaseous phase on the basis of theoretical calculations

    International Nuclear Information System (INIS)

    Dorofeeva, Olga V.; Ryzhova, Oxana N.

    2009-01-01

    The standard molar enthalpies of formation of urea, glycine, and L-alanine in the gaseous phase at 298.15 K were calculated by the high-level Gaussian-3X method. The agreement with the available experimental data is very good for urea and glycine and, thus, supports the high accuracy of calculated values. A significant discrepancy between theoretical and experimental enthalpy of formation values for L-alanine provides a reason to reconsider the experimental data previously used to derive the standard molar enthalpy of formation of L-alanine in the gaseous phase at 298.15 K. To obtain a more reliable value of enthalpy of sublimation at 298.15 K, the heat capacity values of gaseous L-alanine were calculated by standard statistical thermodynamics formulae using molecular parameters determined from B3LYP/cc-pVTZ calculations. With the obtained value of C p,m 0 (L-alanine, g, 298.15 K) = 112.6 ± 4.0 J . K -1 . mol -1 the original published experimental values of enthalpy of sublimation of L-alanine were readjusted to the reference temperature: Δ cr g H m (L-alanine, 298.15 K) = 135.2 ± 2.0 kJ . mol -1 . This value, together with the experimental enthalpy of formation of solid L-alanine, Δ f H m 0 (L-alanine, cr, 298.15 K) = -560.0 ± 1.0 kJ . mol -1 [S.N. Ngauv, R. Sabbah, M. Laffitte, Thermochim. Acta 20 (1977) 371-380; I. Contineanu, D.I. Marchidan, Rev. Roum. Chim. 29 (1984) 43-48], gives a new value for the enthalpy of formation of L-alanine in the gaseous phase, Δ f H m 0 (L-alanine, g, 298.15 K) = -424.8 ± 2.0 kJ . mol -1 , which is in good agreement with our theoretical G3X result, -427.6 ± 4.0 kJ . mol -1 . The same procedure for glycine allowed us to improve the literature value of the enthalpy of formation for this compound, Δ f H m 0 (glycine, g, 298.15 K) = -393.7 ± 1.5 kJ . mol -1 . As a result a set of self-consistent thermochemical data for glycine and L-alanine is proposed

  19. Effect of Hydroxylamine Sulfate on Volumetric Behavior of Glycine, L-Alanine, and L-Arginine in Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2013-01-01

    Full Text Available The apparent molar volumes of glycine, L-alanine, and L-arginine in aqueous hydroxylamine sulfate solutions have been determined at T=298.15 K and atmospheric pressure. The standard partial molar volumes, V20, corresponding partial molar volumes of transfer, ΔtrV20, and hydration numbers, NH, have been calculated for these α-amino acids from the experimental data. The ΔtrV20 values are positive for glycine, L-alanine, and L-arginine and are all increased with the increase in the concentration of hydroxylamine ions. These parameters obtained from the volumetric data are interpreted in terms of various mixing effects between amino acids and hydroxylamine sulfate in aqueous solutions.

  20. Metabolism of [15N]alanine in the ectomycorrhizal fungus Paxillus involutus

    International Nuclear Information System (INIS)

    Chalot, M.; Finlay, R.D.; Ek, H.; Söderström, B.

    1995-01-01

    Chalot, M., Finlay, R. D., Ek, H., and Söderström, B. 1995. Metabolism of [ 15 N]alanine in the ectomycorrhizal fungus Paxillus involutus. Experimental Mycology 19, 297-304. Alanine metabolism in the ectomycorrhizal fungus Paxillus involutus was investigated using [ 15 N]alanine. Short-term exposure of mycelial discs to [ 15 N]alanine showed that the greatest flow of 15 N was to glutamate and to aspartate. Levels of enrichment were as high as 15-20% for glutamate and 13-18% for aspartate, whereas that of alanine reached 30%. Label was also detected in the amino-N of glutamine and in serine and glycine, although at lower levels. Preincubation of mycelia with aminooxyacetate, an inhibitor of transamination reactions. resulted in complete inhibition of the flow of the label to glutamate, aspartate, and amino-N of glutamine, whereas [ 15 N]alanine rapidly accumulated. This evidence indicates the direct involvement of alanine aminotransferase for translocation of 15 N from alanine to glutamate. Alanine may be a convenient reservoir of both nitrogen and carbon. (author)

  1. Un-catalyzed peptide bond formation between two monomers of glycine, alanine, serine, threonine, and aspartic acid in gas phase: a density functional theory study

    Science.gov (United States)

    Bhunia, Snehasis; Singh, Ajeet; Ojha, Animesh K.

    2016-05-01

    In the present report, un-catalyzed peptide bond formation between two monomers of glycine (Gly), alanine (Ala), serine (Ser), threonine (Thr), and aspartic acid (Asp) has been investigated in gas phase via two steps reaction mechanism and concerted mechanism at B3LYP/6-31G(d,p) and M062X/6-31G(d,p) level of theories. The peptide bond is formed through a nucleophilic reaction via transition states, TS1 and TS2 in stepwise mechanism. The TS1 reveals formation of a new C-N bond while TS2 illustrate the formation of C=O bond. In case of concerted mechanism, C-N bond is formed by a single four-centre transition state (TS3). The energy barrier is used to explain the involvement of energy at each step of the reaction. The energy barrier (20-48 kcal/mol) is required for the transformation of reactant state R1 to TS1 state and intermediate state I1 to TS2 state. The large value of energy barrier is explained in terms of distortion and interaction energies for stepwise mechanism. The energy barrier of TS3 in concerted mechanism is very close to the energy barrier of the first transition state (TS1) of the stepwise mechanism for the formation of Gly-Gly and Ala-Ala di- peptide. However, in case of Ser-Ser, Thr-Thr and Asp-Asp di-peptide, the energy barrier of TS3 is relatively high than that of the energy barrier of TS1 calculated at B3LYP/6-31G(d,p) and M062X/6-31G(d,p) level of theories. In both the mechanisms, the value of energy barrier calculated at B3LYP/6-31G(d,p) level of theory is greater than that of the value calculated at M062X/6-31G(d,p) level of theory.

  2. Deficiency in L-serine deaminase interferes with one-carbon metabolism and cell wall synthesis in Escherichia coli K-12.

    Science.gov (United States)

    Zhang, Xiao; El-Hajj, Ziad W; Newman, Elaine

    2010-10-01

    Escherichia coli K-12 provided with glucose and a mixture of amino acids depletes L-serine more quickly than any other amino acid even in the presence of ammonium sulfate. A mutant without three 4Fe4S L-serine deaminases (SdaA, SdaB, and TdcG) of E. coli K-12 is unable to do this. The high level of L-serine that accumulates when such a mutant is exposed to amino acid mixtures starves the cells for C(1) units and interferes with cell wall synthesis. We suggest that at high concentrations, L-serine decreases synthesis of UDP-N-acetylmuramate-L-alanine by the murC-encoded ligase, weakening the cell wall and producing misshapen cells and lysis. The inhibition by high L-serine is overcome in several ways: by a large concentration of L-alanine, by overproducing MurC together with a low concentration of L-alanine, and by overproducing FtsW, thus promoting septal assembly and also by overexpression of the glycine cleavage operon. S-Adenosylmethionine reduces lysis and allows an extensive increase in biomass without improving cell division. This suggests that E. coli has a metabolic trigger for cell division. Without that reaction, if no other inhibition occurs, other metabolic functions can continue and cells can elongate and replicate their DNA, reaching at least 180 times their usual length, but cannot divide.

  3. Effect of glycine and alanine supplementation on development of cattle embryos cultured in CR1aa medium with or without cumulus cells

    Directory of Open Access Journals (Sweden)

    Kr. BREDBACKA

    2008-12-01

    Full Text Available The effect of alanine (1 mM and glycine (10 mM supplementation on bovine embryo development in vitro was investigated. Presumptive bovine zygotes, produced by in vitro maturation and insemination of oocytes, were cultured for 144 h in CR1aa medium in the absence (Experiments 1 and 2 or presence of cumulus cells (Experiment 3. In Experiment 1, the proportion of morulae and blastocysts of cleaved embryos in glycine-supplemented medium was not different from that of the control medium (34% in both mediaglycine-enriched medium (69.5 vs. 53.3, P = 0.016. In Experiment 2, addition of alanine did not improve the formation of morulae and blastocysts (13% vs. 21% in control medium, and the mean cell numbers in morulae and blastocysts were lower than those in the control group (34.3 vs. 68.7, P = 0.007. In the presence of cumulus cells, the combined supplementation of glycine and alanine increased the proportion of morulae and blastocysts over that in the control medium (31% vs. 14%, P = 0.003.;

  4. Autoantibodies in infectious mononucleosis have specificity for the glycine-alanine repeating region of the Epstein-Barr virus nuclear antigen

    Science.gov (United States)

    1987-01-01

    Viruses have been postulated to be involved in the induction of autoantibodies by: autoimmunization with tissue proteins released by virally induced tissue damage; immunization with virally encoded antigens bearing molecular similarities to normal tissue proteins; or nonspecific (polyclonal) B cell stimulation by the infection. Infectious mononucleosis (IM) is an experiment of nature that provides the opportunity for examining these possibilities. We show here that IgM antibodies produced in this disease react with at least nine normal tissue proteins, in addition to the virally encoded Epstein-Barr nuclear antigen (EBNA-1). The antibodies are generated to configurations in the glycine-alanine repeat region of EBNA-1 and are crossreactive with the normal tissue proteins through similar configurations, as demonstrated by the effectiveness of a synthetic glycine-alanine peptide in inhibiting the reactions. The antibodies are absent in preillness sera and gradually disappear over a period of months after illness, being replaced by IgG anti-EBNA-1 antibodies that do not crossreact with the normal tissue proteins but that are still inhibited by the glycine-alanine peptide. These findings are most easily explained by either a molecular mimicry model of IgM autoantibody production or by the polyclonal activation of a germline gene for a crossreactive antibody. It also indicates a selection of highly specific, non-crossreactive anti-EBNA-1 antibodies during IgM to IgG isotype switching. PMID:2435830

  5. Deficiency in l-Serine Deaminase Interferes with One-Carbon Metabolism and Cell Wall Synthesis in Escherichia coli K-12▿

    Science.gov (United States)

    Zhang, Xiao; El-Hajj, Ziad W.; Newman, Elaine

    2010-01-01

    Escherichia coli K-12 provided with glucose and a mixture of amino acids depletes l-serine more quickly than any other amino acid even in the presence of ammonium sulfate. A mutant without three 4Fe4S l-serine deaminases (SdaA, SdaB, and TdcG) of E. coli K-12 is unable to do this. The high level of l-serine that accumulates when such a mutant is exposed to amino acid mixtures starves the cells for C1 units and interferes with cell wall synthesis. We suggest that at high concentrations, l-serine decreases synthesis of UDP-N-acetylmuramate-l-alanine by the murC-encoded ligase, weakening the cell wall and producing misshapen cells and lysis. The inhibition by high l-serine is overcome in several ways: by a large concentration of l-alanine, by overproducing MurC together with a low concentration of l-alanine, and by overproducing FtsW, thus promoting septal assembly and also by overexpression of the glycine cleavage operon. S-Adenosylmethionine reduces lysis and allows an extensive increase in biomass without improving cell division. This suggests that E. coli has a metabolic trigger for cell division. Without that reaction, if no other inhibition occurs, other metabolic functions can continue and cells can elongate and replicate their DNA, reaching at least 180 times their usual length, but cannot divide. PMID:20729359

  6. Effects of a glycine transporter-1 inhibitor and D-serine on MK-801-induced immobility in the forced swimming test in rats.

    Science.gov (United States)

    Kawaura, Kazuaki; Koike, Hiroyuki; Kinoshita, Kohnosuke; Kambe, Daiji; Kaku, Ayaka; Karasawa, Jun-ichi; Chaki, Shigeyuki; Hikichi, Hirohiko

    2015-02-01

    Glutamatergic dysfunction, particularly the hypofunction of N-methyl-D-aspartate (NMDA) receptors, is involved in the pathophysiology of schizophrenia. The positive modulation of the glycine site on the NMDA receptor has been proposed as a novel therapeutic approach for schizophrenia. However, its efficacy against negative symptoms, which are poorly managed by current medications, has not been fully addressed. In the present study, the effects of the positive modulation of the glycine site on the NMDA receptor were investigated in an animal model of negative symptoms of schizophrenia. The subchronic administration of MK-801 increased immobility in the forced swimming test in rats without affecting spontaneous locomotor activity. The increased immobility induced by MK-801 was attenuated by the atypical antipsychotic clozapine but not by either the typical antipsychotic haloperidol or the antidepressant imipramine, indicating that the increased immobility induced by subchronic treatment with MK-801 in the forced swimming test may represent a negative symptom of schizophrenia. Likewise, positive modulation of the glycine sites on the NMDA receptor using an agonist for the glycine site, D-serine, and a glycine transporter-1 inhibitor, N-[(3R)-3-([1,1'-biphenyl]-4-yloxy)-3-(4-fluorophenyl)propyl]-N-methylglycine hydrochloride (NFPS), significantly reversed the increase in immobility in MK-801-treated rats without reducing the immobility time in vehicle-treated rats. The present results show that the stimulation of the NMDA receptor through the glycine site on the receptor either directly with D-serine or by blocking glycine transporter-1 attenuates the immobility elicited by the subchronic administration of MK-801 and may be potentially useful for the treatment of negative symptoms of schizophrenia. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. [1-14C]Glycolate metabolism and serine biosynthesis in soybean plants

    International Nuclear Information System (INIS)

    Calmes, J.; Viala, G.; Latche, J.C.; Cavalie, G.

    1977-01-01

    [1- 14 C]Glycolate metabolism was examined in leafy shoots of soybean plants (Glycine max (L.) Merr., var. Adepta). Only small amounts of 14 C were incorporated into evolved carbon dioxide and glucidic compounds. Free and protein glycine was labelled but higher levels of radioactivity were found in free serine. Changes in the distribution of 14 C with time showed that metabolic conversion glycollate → glycineserine occurred very early and serine biosynthesis was more important in the shoot than in the leaves. Carbon dioxide labelling was always slight compared to serine labelling. These data suggest strong relations between glycollate and nitrogen metabolism

  8. The effect of amino acid backbone length on molecular packing: crystalline tartrates of glycine, β-alanine, γ-aminobutyric acid (GABA) and DL-α-aminobutyric acid (AABA).

    Science.gov (United States)

    Losev, Evgeniy; Boldyreva, Elena

    2018-02-01

    We report a novel 1:1 cocrystal of β-alanine with DL-tartaric acid, C 3 H 7 NO 2 ·C 4 H 6 O 6 , (II), and three new molecular salts of DL-tartaric acid with β-alanine {3-azaniumylpropanoic acid-3-azaniumylpropanoate DL-tartaric acid-DL-tartrate, [H(C 3 H 7 NO 2 ) 2 ] + ·[H(C 4 H 5 O 6 ) 2 ] - , (III)}, γ-aminobutyric acid [3-carboxypropanaminium DL-tartrate, C 4 H 10 NO 2 + ·C 4 H 5 O 6 - , (IV)] and DL-α-aminobutyric acid {DL-2-azaniumylbutanoic acid-DL-2-azaniumylbutanoate DL-tartaric acid-DL-tartrate, [H(C 4 H 9 NO 2 ) 2 ] + ·[H(C 4 H 5 O 6 ) 2 ] - , (V)}. The crystal structures of binary crystals of DL-tartaric acid with glycine, (I), β-alanine, (II) and (III), GABA, (IV), and DL-AABA, (V), have similar molecular packing and crystallographic motifs. The shortest amino acid (i.e. glycine) forms a cocrystal, (I), with DL-tartaric acid, whereas the larger amino acids form molecular salts, viz. (IV) and (V). β-Alanine is the only amino acid capable of forming both a cocrystal [i.e. (II)] and a molecular salt [i.e. (III)] with DL-tartaric acid. The cocrystals of glycine and β-alanine with DL-tartaric acid, i.e. (I) and (II), respectively, contain chains of amino acid zwitterions, similar to the structure of pure glycine. In the structures of the molecular salts of amino acids, the amino acid cations form isolated dimers [of β-alanine in (III), GABA in (IV) and DL-AABA in (V)], which are linked by strong O-H...O hydrogen bonds. Moreover, the three crystal structures comprise different types of dimeric cations, i.e. (A...A) + in (III) and (V), and A + ...A + in (IV). Molecular salts (IV) and (V) are the first examples of molecular salts of GABA and DL-AABA that contain dimers of amino acid cations. The geometry of each investigated amino acid (except DL-AABA) correlates with the melting point of its mixed crystal.

  9. Oxygen-18 as a tool for studying photorespiration. Oxygen uptake and incorporation into glycolate, glycine and serine

    International Nuclear Information System (INIS)

    Gerster, R.; Dimon, B.; Tournier, P.; Peybernes, A.

    1977-01-01

    The intensity of photosynthesis and photorespiration has been determined by measuring 16 O 2 evolvement and 18 O 2 uptake on algae and leaves. In the case of algae, there is still an important oxygen uptake even when ribulose diphosphate oxygenase is inhibited by 10 -3 M cyanide. Oxygen-18 incorporation into glycolate, glycine and serine of photorespiring algae and leaves exposed to atmospheres containing 18 O 2 has also been measured. Only one of the two atoms present in molecular oxygen was incorporated into the carboxyl group of the glycolate excreted from algae; the rate of 18 O incorporation was important (65 to 80% according to experimental conditions), even in the presence of 10 -3 M cyanide. Thus, oxidation of ribulose diphosphate is not the sole reaction leading to 18 O glycolate synthesis. In the case of maize, there was a rapid and important 18 O incorporation into the carboxyl group of glycine and serine, the kinetics of which was determined as a function of CO 2 presence in the atmosphere. These results suggest that photorespiration is also operating in C 4 species. Furthermore, in vitro experiments showed that phosphorylated ceto-acids of the Calvin cycle were very sensitive to H 2 O 2 ; the corresponding reaction can explain O 2 uptake and 18 O labelling of glycolate. (author)

  10. Inhibition of serine palmitoyltransferase in vitro and long-chain base biosynthesis in intact Chinese hamster ovary cells by β-Cl-alanine

    International Nuclear Information System (INIS)

    Medlock, K.A.; Merrill, A.H. Jr.

    1987-01-01

    Serine palmitoyltransferase (SPT) is a pyridoxal-5'-phosphate dependent enzyme that catalyzes the first committed step of long-chain base (LCB) synthesis. Inhibition of SPT activity and de novo biosynthesis of sphinganine and sphingosine was observed in vitro and in intact Chinese hamster ovary cells (CHO). In vitro studies revealed that inhibition was irreversible and concentration- and time-dependent, which are characteristics of suicide inhibition. Incubation of intact CHO cells with 5 mM β-Cl-alanine for 15 min completely inhibited SPT activity and LCB synthesis from [ 14 C]serine. The concentration dependences of inhibition of SPT activity and LCB formation were identical. There was no loss of viability of recovery of SPT activity over the 2 hour time course of these experiments. The synthesis of several other lipids was not affected by the same treatment. These results establish the association between the activity of SPT and the cellular rate of LCB formation and indicate that β-Cl-alanine can be used to study alterations in cellular LCB synthesis

  11. Comparison of the UDP-N-Acetylmuramate:l-Alanine Ligase Enzymes from Mycobacterium tuberculosis and Mycobacterium leprae

    OpenAIRE

    Mahapatra, Sebabrata; Crick, Dean C.; Brennan, Patrick J.

    2000-01-01

    In the peptidoglycan of Mycobacterium leprae, l-alanine of the side chain is replaced by glycine. When expressed in Escherichia coli, MurC (UDP-N-acetyl-muramate:l-alanine ligase) of M. leprae showed Km and Vmax for l-alanine and glycine similar to those of Mycobacterium tuberculosis MurC, suggesting that another explanation should be sought for the presence of glycine.

  12. Comparison of the UDP-N-Acetylmuramate:l-Alanine Ligase Enzymes from Mycobacterium tuberculosis and Mycobacterium leprae

    Science.gov (United States)

    Mahapatra, Sebabrata; Crick, Dean C.; Brennan, Patrick J.

    2000-01-01

    In the peptidoglycan of Mycobacterium leprae, l-alanine of the side chain is replaced by glycine. When expressed in Escherichia coli, MurC (UDP-N-acetyl-muramate:l-alanine ligase) of M. leprae showed Km and Vmax for l-alanine and glycine similar to those of Mycobacterium tuberculosis MurC, suggesting that another explanation should be sought for the presence of glycine. PMID:11073931

  13. Gas-phase reactions of glycine, alanine, valine and their N-methyl derivatives with the nitrosonium ion, NO+.

    Science.gov (United States)

    Freitas, M A; O'Hair, R A; Schmidt, J A; Tichy, S E; Plashko, B E; Williams, T D

    1996-10-01

    The gas-phase reactions of the nitrosonium ion, NO+ with the amino acids glycine, alanine and valine and their N-methyl derivatives were investigated under chemical ionization mass spectrometric (CIMS) conditions. Two products were observed in all cases: the formation of the iminium ion and the formation of an [M-H]+ ion. The latter product is consistent with a reaction channel involving hydride abstraction by NO+, and was confirmed by (i) examining the Ar+CI mass spectra of the same amino acids under similar source conditions and (ii) examining the unimolecular fragmentation reactions of the [M + H]+ ions of the N-nitroso-N-methyl derivatives of each of the amino acids in a tandem mass spectrometer. Further insights into the reaction of glycine with NO+ were obtained by performing ab initio calculations (at the MP2/6-31G* parallel HF/6-31G* level). These results indicate that four reactions are thermodynamically viable for glycine: (i) hydride abstraction; (ii) iminium ion formation (with concomitant loss of HONO and CO); (iii) diazonium ion formation; and (iv) diazonium ion formation followed by loss of N2. Possible reasons why reactions (iii) and (iv) are not observed are discussed, and comparisons with solution reactivity and the gas-phase reactivity of NO+ are also made.

  14. Alanine Counteracts the Destabilizing Effect that Urea has on RNase-A.

    Science.gov (United States)

    Chowhan, Rimpy K; Ali, Fasil; Bhat, Mohd Y; Rahman, Safikur; Singh, Laishram R; Ahmad, Faizan; Dar, Tanveer A

    2016-01-01

    It is generally believed that organisms use and accumulate methylamine osmolytes to prevent urea's damaging effect on protein stability and activity. However, urea-rich cells not only accumulate methylamines but also many other methylated and non-methylated compounds as well. But, so far it is not known whether osmolytes that are not accumulated in urea-rich cells could also confer urea-counteracting properties. We investigated the behavior of a non-methylamine osmolyte, alanine for its counteracting effect against urea denaturation of a model protein, ribonuclease A (RNase-A). We have measured structure and thermodynamic parameters (Tm, ΔHm, and ΔGD°) of RNase-A in the presence of alanine, urea and their combination. The results were also compared with the ability of glycine (osmolyte lacking one methyl group when compared with alanine) to counter urea's effect on protein stability. We observed that alanine but not glycine counteracts urea's harmful effect on RNase-A stability. The results indicated that alanine (in addition to methylamine osmolytes) may serve as an alternate urea-counteractant. Since glycine fails to protect RNase-A from urea's destabilizing effect, it seems that methylation to glycine might have some evolutionary significance to protect proteins against harmful effects of urea.

  15. Volumetric properties for glycine and L-serine in aqueous solutions of 1-Ethyl-3-methylimidazolium hydrogen sulfate ([Emim][HSO4]) at T = (293.15–313.15) K and ambient pressure

    International Nuclear Information System (INIS)

    Rafiee, Hamid Reza; Frouzesh, Farshid

    2016-01-01

    Highlights: • Ternary systems (amino acid + ionic liquid + H 2 O) are considered. • Volumetric properties including density, V φ , ΔV φ 0 and E φ 0 are determined. • Glycine and L-serine were amino acids and [Emim][HSO 4 ] was IL studied. • V φ values for amino acids increased with both concentration of amino acids and temperature. • Both studied amino acids act as structure maker in ternary systems. - Abstract: By using the volumetric properties, the solute–solvent interactions are studied in the ternary (glycine + 1-Ethyl-3-methylimidazolium hydrogen sulfate [Emim][HSO 4 ] + water) and (L-serine + 1-Ethyl-3-methylimidazolium hydrogen sulfate [Emim][HSO 4 ] + water) systems. For this purpose, the apparent molar volumes, V φ , are calculated from the experimental density data. To obtain limiting apparent molar volumes V φ 0 , the apparent molar volume values are fitted to the Redlich-Mayer type equation. Then the limiting apparent molar volumes of transfer, ΔV φ 0 , for studied amino acids from water to aqueous solutions of ionic liquid (IL) are calculated. The results showed that the ΔV φ 0 values are negative for both ternary systems at all temperatures. The limiting apparent molar expansibility E φ 0 values have been obtained from the first derivative of limiting apparent molar volumes with respect to temperature. The values of second derivative of limiting apparent molar volumes respect to temperature show the structure making or breaking ability of glycine and L-serine in studied IL aqueous solutions. The results indicated that glycine and L-serine act as structure maker in studied solutions. McMillan–Mayer theory is used for evaluating the interaction parameters. Also the hydration number, n H , for both amino acids in ternary solutions has been reported.

  16. [Alanine solution as enzyme reaction buffer used in A to O blood group conversion].

    Science.gov (United States)

    Li, Su-Bo; Zhang, Xue; Zhang, Yin-Ze; Tan, Ying-Xia; Bao, Guo-Qiang; Wang, Ying-Li; Ji, Shou-Ping; Gong, Feng; Gao, Hong-Wei

    2014-06-01

    The aim of this study was to investigate the effect of alanine solution as α-N-acetylgalactosaminidase enzyme reaction buffer on the enzymatic activity of A antigen. The binding ability of α-N-acetylgalactosaminidase with RBC in different reaction buffer such as alanine solution, glycine solution, normal saline (0.9% NaCl), PBS, PCS was detected by Western blot. The results showed that the efficiency of A to O conversion in alanine solution was similar to that in glycine solution, and Western blot confirmed that most of enzymes blinded with RBC in glycine or alanine solution, but few enzymes blinded with RBC in PBS, PCS or normal saline. The evidences indicated that binding of enzyme with RBC was a key element for A to O blood group conversion, while the binding ability of α-N-acetylgalactosaminidase with RBC in alanine or glycine solution was similar. It is concluded that alanine solution can be used as enzyme reaction buffer in A to O blood group conversion. In this buffer, the α-N-acetylgalactosaminidase is closely blinded with RBC and α-N-acetylgalactosaminidase plays efficient enzymatic activity of A antigen.

  17. In vivo NMR analysis of incorporation of [2-13C] glycine into silk fibroin

    International Nuclear Information System (INIS)

    Asakura, Tetsuo; Nagashima, Mariko; Demura, Makoto; Osanai, Minoru.

    1990-01-01

    The biosynthetic mechanism of silk fibroin in silkworms, Bombyx mori, is unique because this fibrous protein composed mainly of glycine, alanine and serine is produced very rapidly in large quantity in the posterior silk glands. It is very meaningful to investigate into the biosynthesis of silk protein under nondestructive condition by in vivo NMR and C-13 labeling techniques. The sugar metabolism related to the production of silk fibroin was analyzed by monitoring the change in the C-13 labeled peaks in the NMR spectra for silkworms. In this paper, the monitoring of the 2-(C-13) glycine metabolism in Bombyx mori by the C-13 NMR in vivo is reported. In particular, the in vivo transport of glycine from the midgut to the posterior silk gland was measured, and the rate constants were determined with the course of the peak intensity in the C-13 NMR spectra. It is possible to discuss quantitatively the in vivo production of silk fibroin with these rate constants. The experiment and the results are reported. The in vivo C-13 NMR spectra of a 5 day old, 5th instar larva of Bombyx mori after the oral administration of 2-(C-13) glycine are shown. The significant increase of the peak intensity occurred. (K.I.)

  18. Excess of L-Alanine in Amino Acids Synthesized in a Plasma Torch Generated by a Hypervelocity Meteorite Impact Reproduced in the Laboratory

    Science.gov (United States)

    Managadze, George G.; Engle, Michael H.; Getty, Stephanie A.; Wurz, Peter; Brinckerhoff, William B.; Shokolov, Anatoly; Sholin, Gennady; Terent'ev, Sergey A.; Chumikov, Alexander E.; Skalkin, Alexander S

    2016-01-01

    We present a laboratory reproduction of hypervelocity impacts of a carbon containing meteorite on a mineral substance representative of planetary surfaces. The physical conditions of the resulting impact plasma torch provide favorable conditions for abiogenic synthesis of protein amino acids: We identified glycine and alanine, and in smaller quantities serine, in the produced material. Moreover, we observe breaking of alanine mirror symmetry with L excess, which coincides with the bioorganic world. Therefore the selection of L-amino acids for the formation of proteins for living matter could have been the result from plasma processes occurring during the impact meteorites on the surface. This indicates that the plasma torch from meteorite impacts could play an important role in the formation of biomolecular homochirality. Thus, meteorite impacts possibly were the initial stage of this process and promoted conditions for the emergence of a living matter.

  19. Serine biosynthesis and transport defects.

    Science.gov (United States)

    El-Hattab, Ayman W

    2016-07-01

    l-serine is a non-essential amino acid that is biosynthesized via the enzymes phosphoglycerate dehydrogenase (PGDH), phosphoserine aminotransferase (PSAT), and phosphoserine phosphatase (PSP). Besides its role in protein synthesis, l-serine is a potent neurotrophic factor and a precursor of a number of essential compounds including phosphatidylserine, sphingomyelin, glycine, and d-serine. Serine biosynthesis defects result from impairments of PGDH, PSAT, or PSP leading to systemic serine deficiency. Serine biosynthesis defects present in a broad phenotypic spectrum that includes, at the severe end, Neu-Laxova syndrome, a lethal multiple congenital anomaly disease, intermediately, infantile serine biosynthesis defects with severe neurological manifestations and growth deficiency, and at the mild end, the childhood disease with intellectual disability. A serine transport defect resulting from deficiency of the ASCT1, the main transporter for serine in the central nervous system, has been recently described in children with neurological manifestations that overlap with those observed in serine biosynthesis defects. l-serine therapy may be beneficial in preventing or ameliorating symptoms in serine biosynthesis and transport defects, if started before neurological damage occurs. Herein, we review serine metabolism and transport, the clinical, biochemical, and molecular aspects of serine biosynthesis and transport defects, the mechanisms of these diseases, and the potential role of serine therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Characterization of serine hydroxymethyltransferase GlyA as a potential source of D-alanine in Chlamydia pneumoniae.

    Science.gov (United States)

    De Benedetti, Stefania; Bühl, Henrike; Gaballah, Ahmed; Klöckner, Anna; Otten, Christian; Schneider, Tanja; Sahl, Hans-Georg; Henrichfreise, Beate

    2014-01-01

    For intracellular Chlamydiaceae, there is no need to withstand osmotic challenges, and a functional cell wall has not been detected in these pathogens so far. Nevertheless, penicillin inhibits cell division in Chlamydiaceae resulting in enlarged aberrant bodies, a phenomenon known as chlamydial anomaly. D-alanine is a unique and essential component in the biosynthesis of bacterial cell walls. In free-living bacteria like Escherichia coli, penicillin-binding proteins such as monofunctional transpeptidases PBP2 and PBP3, the putative targets of penicillin in Chlamydiaceae, cross-link adjacent peptidoglycan strands via meso-diaminopimelic acid and D-Ala-D-Ala moieties of pentapeptide side chains. In the absence of genes coding for alanine racemase Alr and DadX homologs, the source of D-Ala and thus the presence of substrates for PBP2 and PBP3 activity in Chlamydiaceae has puzzled researchers for years. Interestingly, Chlamydiaceae genomes encode GlyA, a serine hydroxymethyltransferase that has been shown to exhibit slow racemization of D- and L-alanine as a side reaction in E. coli. We show that GlyA from Chlamydia pneumoniae can serve as a source of D-Ala. GlyA partially reversed the D-Ala auxotrophic phenotype of an E. coli racemase double mutant. Moreover, purified chlamydial GlyA had racemase activity on L-Ala in vitro and was inhibited by D-cycloserine, identifying GlyA, besides D-Ala ligase MurC/Ddl, as an additional target of this competitive inhibitor in Chlamydiaceae. Proof of D-Ala biosynthesis in Chlamydiaceae helps to clarify the structure of cell wall precursor lipid II and the role of chlamydial penicillin-binding proteins in the development of non-dividing aberrant chlamydial bodies and persistence in the presence of penicillin.

  1. Characterization of serine hydroxymethyltransferase GlyA as a potential source of D-alanine in Chlamydia pneumoniae

    Directory of Open Access Journals (Sweden)

    Stefania eDe Benedetti

    2014-02-01

    Full Text Available For intracellular Chlamydiaceae, there is no need to withstand osmotic challenges, and a functional cell wall has not been detected in these pathogens so far. Nevertheless, penicillin inhibits cell division in Chlamydiaceae resulting in enlarged aberrant bodies, a phenomenon known as chlamydial anomaly.D-alanine is a unique and essential component in the biosynthesis of bacterial cell walls. In free-living bacteria like Escherichia coli, penicillin-binding proteins such as monofunctional transpeptidases PBP2 and PBP3, the putative targets of penicillin in Chlamydiaceae, cross-link adjacent peptidoglycan strands via meso-diaminopimelic acid and D-Ala-D-Ala moieties of pentapeptide side chains. In the absence of genes coding for alanine racemase Alr and DadX homologs, the source of D-Ala and thus the presence of substrates for PBP2 and PBP3 activity in Chlamydiaceae has puzzled researchers for years. Interestingly, Chlamydiaceae genomes encode GlyA, a serine hydroxymethyltransferase that has been shown to exhibit slow racemization of D- and L- alanine as a side reaction in E. coli. We show that GlyA from Chlamydia pneumoniae can serve as a source of D-Ala. GlyA partially reversed the D-Ala auxotrophic phenotype of an E. coli racemase double mutant. Moreover, purified chlamydial GlyA had racemase activity on L-Ala in vitro and was inhibited by D-cycloserine, identifying GlyA, besides D-Ala ligase MurC/Ddl, as an additional target of this competitive inhibitor in Chlamydiaceae. Proof of D-Ala biosynthesis in Chlamydiaceae helps to clarify the structure of cell wall precursor lipid II and the role of chlamydial penicillin-binding proteins in the development of non-dividing aberrant chlamydial bodies and persistence in the presence of penicillin.

  2. Glycine metabolism by Pseudomonas aeruginosa: hydrogen cyanide biosynthesis

    International Nuclear Information System (INIS)

    Castric, P.A.

    1977-01-01

    Hydrogen cyanide (HCN) production by Pseudomonas aeruginosa in a synthetic medium is stimulated by the presence of glycine. Methionine enhances this stimulation but will not substitute for glycine as a stimulator of cyanogenesis. Threonine and phenylalanine are effective substitutes for glycine in the stimulation of HCN production. Glycine, threonine, and serine are good radioisotope precursors of HCN, but methionine and phenylalanine are not. Cell extracts of P. aeruginosa convert [ 14 C]threonine to [ 14 C]glycine. H14CN is produced with low dilution of label from either [1- 14 C]glycine or [2- 14 C]glycine, indicating a randomization of label either in the primary or secondary metabolism of glycine. When whole cells were fed [1,2- 14 C]glycine, cyanide and bicarbonate were the only radioactive extracellular products observed

  3. Resolving the limitations of using glycine as EPR dosimeter in the intermediate level of gamma dose

    Science.gov (United States)

    Aboelezz, E.; Hassan, G. M.

    2018-04-01

    The dosimetric properties of the simplest amino acid "glycine"- using EPR technique- were investigated in comparison to reference standard alanine dosimeter. The EPR spectrum of glycine at room temperature is complex, but immediately after irradiation, it appears as a triplet hyperfine structure probably due to the dominant contribution of the (•CH2COO-) radical. The dosimetric peak of glycine is at g-factor 2.0026 ± 0.0015 and its line width is 9 G at large modulation amplitude (7 G). The optimum microwave was studied and was found to be as alanine 8 mW; the post-irradiation as well as the dose rate effects were discussed. Dosimetric peak intensity of glycine fades rapidly to be about one quarter of its original value during 20 days for dried samples and it stabilizes after that. The dose response study in an intermediate range (2-1000 Gy) reveals that the glycine SNR is about 2 times more than that of alanine pellets when measured immediately after irradiation and 4 times more than that of glycine itself after 22 days of irradiation. The effect of energy dependence was studied and interpreted theoretically by calculation of mass energy absorption coefficient. The calculated combined uncertainties for glycine and alanine are nearly the same and were found to be 2.42% and 2.33%, respectively. Glycine shows interesting dosimetric properties in the range of ionizing radiation doses investigated.

  4. Amino acid metabolism in plant leaf, 1

    International Nuclear Information System (INIS)

    Ito, Osamu; Kumazawa, Kikuo

    1977-01-01

    14C-labelled sodium bicarbonate and 15N-labelled ammonium sulfate were simultaneously vacuum-infiltrated into detached sunflower leaves, and the incorporation of 14C and 15N into free amino acids was chased during 60-min period in the light and in the dark. In the light, the 14C specific activity of aspartic acid, alanine, serine and glycine rapidly increased for 5 min and thereafter decreased. On the other hand, that of glutamic acid continued to increase slowly during the entire 60-min period. In the dark, aspartic acid most actively incorporated 14C. The difference of changes in 14C specific activity between glutamic acid and other amino acids was also observed in the dark as in the light. These results suggest that the carbon skeleton of glutamic acid is synthesized from aspartic acid, alanine, serine and glycine. 15N content of glutamine was the highest of all amino acids investigated in the light, and it was followed by glutamic acid, alanine, aspartic acid, serine and glycine, in this order. In the dark, 15N content of glutamic acid fell remarkably and was lower than that of alanine up to 5 min. From these 15N tracer experiments, it is suggested that the incorporation of ammonium into glutamic acid is strictly dependent on light and that alanine incorporates ammonium by the direct animation besides the transamination from glutamic acid. (auth.)

  5. Adição de alanina, glicina e glutamina ao meio crioprotetor seminal de garanhões Mangalarga Marchador Addition of alanine, glycine and glutamine to frozen seminal extender from Mangalarga Marchador stallions

    Directory of Open Access Journals (Sweden)

    Bruno Fagundes

    2010-02-01

    Full Text Available Objetivou-se neste trabalho verificar o efeito da adição de alanina, glicina e glutamina ao meio crioprotetor seminal de garanhões Mangalarga Marchador. Foram utilizados cinco garanhões provenientes do haras Lugavi. Três ejaculados de cada garanhão, após coleta e avaliação, foram divididos em seis tratamentos: sem adição de aminoácidos, adição de 40 mM de alanina, adição de 40 mM de glicina, adição de 60 mM de glutamina, adição de 7 mM de alanina + 7 mM de glicina + 20 mM de glutamina e adição de 40 mM de alanina + 40 mM de glicina + 60 mM de glutamina ao diluente de congelamento convencional. Foram avaliados os parâmetros motilidade total, motilidade progressiva, retidão, linearidade, velocidade média do percurso, velocidade linear, velocidade curvilínea, amplitude lateral de cabeça e frequência de batimentos dos espermatozoides por meio de análise espermática assistida por computador (CASA, funcionalidade da membrana plasmática por choque hiposmótico e integridade de membrana acrossomal pelo teste FITC-PSA. Não houve melhora nos parâmetros de motilidade e cinética espermática nem na funcionalidade de membrana, entretanto, a adição de aminoácidos ao meio crioprotetor seminal aumentou o número de espermatozoides com membrana acrossomal íntegra. Os melhores resultados neste teste são obtidos com 40 mM de alanina (78,6 ± 13,6, 40 mM de glicina (74,7 ± 19,6 ou 7 mM de alanina + 7 mM de glicina + 20 mM de glutamina (76,8 ± 17,5, porém outros estudos devem ser realizados para determinação da concentração ideal desses componentes.The objective of this study was to analyze the effect of the addition of alanine, glycine and glutamine on frozen seminal extender of Mangalarga marchador breed stallions. Five stallions were used from the Lugavi stables. Three ejaculates from each stallion were divided into six treatments: without the addition of amino acids, addition of 40 mM alanine, addition of 40 m

  6. Structural and Functional Adaptation of Vancomycin Resistance VanT Serine Racemases.

    Science.gov (United States)

    Meziane-Cherif, Djalal; Stogios, Peter J; Evdokimova, Elena; Egorova, Olga; Savchenko, Alexei; Courvalin, Patrice

    2015-08-11

    Vancomycin resistance in Gram-positive bacteria results from the replacement of the D-alanyl-D-alanine target of peptidoglycan precursors with D-alanyl-D-lactate or D-alanyl-D-serine (D-Ala-D-Ser), to which vancomycin has low binding affinity. VanT is one of the proteins required for the production of D-Ala-D-Ser-terminating precursors by converting L-Ser to D-Ser. VanT is composed of two domains, an N-terminal membrane-bound domain, likely involved in L-Ser uptake, and a C-terminal cytoplasmic catalytic domain which is related to bacterial alanine racemases. To gain insight into the molecular function of VanT, the crystal structure of the catalytic domain of VanTG from VanG-type resistant Enterococcus faecalis BM4518 was determined. The structure showed significant similarity to type III pyridoxal 5'-phosphate (PLP)-dependent alanine racemases, which are essential for peptidoglycan synthesis. Comparative structural analysis between VanTG and alanine racemases as well as site-directed mutagenesis identified three specific active site positions centered around Asn696 which are responsible for the L-amino acid specificity. This analysis also suggested that VanT racemases evolved from regular alanine racemases by acquiring additional selectivity toward serine while preserving that for alanine. The 4-fold-lower relative catalytic efficiency of VanTG against L-Ser versus L-Ala implied that this enzyme relies on its membrane-bound domain for L-Ser transport to increase the overall rate of d-Ser production. These findings illustrate how vancomycin pressure selected for molecular adaptation of a housekeeping enzyme to a bifunctional enzyme to allow for peptidoglycan remodeling, a strategy increasingly observed in antibiotic-resistant bacteria. Vancomycin is one of the drugs of last resort against Gram-positive antibiotic-resistant pathogens. However, bacteria have evolved a sophisticated mechanism which remodels the drug target, the D-alanine ending precursors in cell wall

  7. Inhibition of serine palmitoyltransferase in vitro and long-chain base biosynthesis in intact Chinese hamster ovary cells by β-chloroalanine

    International Nuclear Information System (INIS)

    Medlock, K.A.; Merrill, A.H. Jr.

    1988-01-01

    The effects of β-chloroalanine (β-Cl-alanine) on the serine palmitoyltransferase activity and the de novo biosynthesis of sphinganine and sphingenine were investigated in vitro with rat liver microsomes and in vivo with intact Chinese hamster ovary (CHO) cells. The inhibition in vitro was rapid, irreversible, and concentration and time dependent and apparently involved the active site because inactivation only occurred with β-Cl-L-alanine and was blocked by L-serine. These are characteristics of mechanism-based (suicide) inhibition. Serine palmitoyltransferase (SPT) was also inhibited when intact CHO cells were incubated with β-Cl-alanine and this treatment inhibited [ 14 C]serine incorporation into long-chain bases by intact cells. The concentration dependence of the loss of SPT activity and of long-chain base synthesis was identical. The effects of β-Cl-alanine appeared to occur with little perturbation of other cell functions: the cells exhibited no loss in cell viability, [ 14 C]serine uptake was not blocked, total lipid biosynthesis from [ 14 C]acetic acid was not decreased (nor was the appearance of radiolabel in cholesterol and phosphatidylcholine), and [ 3 H]thymidine incorporation into DNA was not affected. There appeared to be little effect on protein synthesis based on the incorporation of [ 3 H]leucine, which was only decreased by 14%. Although β-Cl-L-alanine is known to inhibit other pyridoxal 5'-phosphate dependent enzymes, alanine and aspartate transaminases were not inhibited under these conditions. These results establish the close association between the activity of serine palmitoyltransferase and the cellular rate of long-chain base formation and indicate that β-Cl-alanine and other mechanism-based inhibitors might be useful to study alterations in cellular long-chain base synthesis

  8. Fluxomics of the Eastern Oyster for Environmental Stress Studies

    Directory of Open Access Journals (Sweden)

    Andrey P. Tikunov

    2014-01-01

    Full Text Available The metabolism of 2-13C/15N-glycine and U-13C-glucose was determined in four tissue blocks (adductor muscle, stomach and digestive gland, mantle, and gills of the Eastern oyster (Crassostrea virginica using proton (1H and carbon-13 (13C nuclear magnetic resonance (NMR spectroscopy. The oysters were treated in aerated seawater with three treatments (5.5 mM U-13C-glucose, 2.7 mM 2-13C/15N-glycine, and 5.5 mM U-13C-glucose plus 2.7 mM 2-13C/15N-glycine and the relative mass balance and 13C fractional enrichments were determined in the four tissue blocks. In all tissues, glycine was metabolized by the glycine cycle forming serine exclusively in the mitochondria by the glycine cleavage system forming 2,3-13C-serine. In muscle, a minor amount of serine-derived pyruvate entered the Krebs cycle as substantiated by detection of a trace of 2,3-13C-aspartate. In all tissues, U-13C-glucose formed glycogen by glycogen synthesis, alanine by glycolysis, and glutamate and aspartate through the Krebs cycle. Alanine was formed exclusively from glucose via alanine transaminase and not glycine via alanine-glyoxylate transaminase. Based on isotopomer analysis, pyruvate carboxylase and pyruvate dehydrogenase appeared to be equal points for pyruvate entry into the Krebs cycle. In the 5.5 mM U-13C-glucose plus 2.7 mM 2-13C/15N-glycine emergence treatment used to simulate 12 h of “low tide”, oysters accumulated more 13C-labeled metabolites, including both anaerobic glycolytic and aerobic Krebs cycle intermediates. The aerobic metabolites could be the biochemical result of the gaping behavior of mollusks during emergence. The change in tissue distribution and mass balance of 13C-labeled nutrients (U-13C-glucose and 2-13C/15N-glycine provides the basis for a new quantitative fluxomic method for elucidating sub-lethal environmental effects in marine organisms called whole body mass balance phenotyping (WoMBaP.

  9. Effect of sodium caproate on the volumetric and viscometric properties of glycine, DL-α-alanine, and DL-α-amino-n-butyric acid in aqueous solutions

    International Nuclear Information System (INIS)

    Wang Jianji; Yan Zhenning; Lu Jinsuo

    2004-01-01

    The apparent molar volumes (V m,2 ) and relative viscosities (η r ) at T=(298.15 and 308.15) K have been obtained for glycine, DL-α-alanine, and DL-α-amino-butyric acid in aqueous sodium caproate solutions from measurements of density and the flow time. The standard partial molar volumes (V 0 m,2 ), standard volumes of transfer (Δ t V 0 ), the viscosity B-coefficients, and the activation thermodynamic quantities (Δμ 2 0≠ and ΔS 2 0≠ ) of viscous flow have been calculated for the amino acids. It is shown that the standard partial molar volumes, viscosity B-coefficients, and activation free energies for viscous flow increase with increasing number of carbon atoms in the alkyl chain of the amino acids. An increase in V 0 m,2 and Δ t V 0 with increasing electrolyte concentrations have been explained due to the interactions of sodium caproate with the charged center of zwitterions for the amino acids. A comparison of the V 0 m,2 values for glycine, DL-α-alanine, and DL-α-aminon-n-butyric acid in different aqueous salts solutions showed that carboxylate ions have stronger interactions with amino acid than chloride, thiocyanate, and nitrate ions. Results of viscosity are discussed in terms of changes in solvent structure

  10. Conformational variability of the glycine receptor M2 domain in response to activation by different agonists

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Dibas, Mohammed I; Lester, Henry A

    2007-01-01

    change. Although taurine and beta-alanine were weak partial agonists at the alpha1R19'C glycine receptor, they induced large fluorescence changes. Propofol, which drastically enhanced these currents, did not induce a glycine-like blue shift in the spectral emission peak. The inhibitors strychnine...... and picrotoxin elicited fluorescence and current changes as expected for a competitive antagonist and an open channel blocker, respectively. Glycine and taurine (or beta-alanine) also produced an increase and a decrease, respectively, in the fluorescence of a label attached to the nearby L22'C residue. Thus...

  11. A comparative study of the adsorption and oxidation of L-alanine and L-serine on Au(1 0 0), Au(1 1 1) and gold thin film electrodes in acid media

    International Nuclear Information System (INIS)

    Sandoval, Andrea P.; Orts, José Manuel; Rodes, Antonio; Feliu, Juan M.

    2013-01-01

    The adsorption and oxidation of L-alanine and L-serine at Au(1 1 1) and Au(1 0 0) single crystal and evaporated thin-film electrodes with preferential (1 1 1) orientation was studied in perchloric acid solutions. For this purpose, cyclic voltammetry experiments were combined with external reflection infrared spectroscopy (gold single crystals) and surface-enhanced infrared reflection–absorption spectroscopy under attenuated total reflection conditions (ATR-SEIRAS) (gold thin films). In addition, theoretical harmonic vibrational frequencies, obtained from B3LYP/LANL2DZ, 6-31+G(d) calculations for the zwitterionic species adsorbed on Au clusters with (1 1 1) orientation, were used to interpret the experimental spectra. The optimized geometry obtained from DFT calculations for the corresponding zwitterion plus a water molecule, under the application of an external electric field of 0.01 a.u. corresponds to a bidentate asymmetrical bridge adsorption configuration. The absence of an adsorbate band for the asymmetric OCO stretching in the experimental infrared spectra confirms the bidentate bonding of the adsorbed zwitterion through the oxygen atoms of the carboxylate group irrespective of the crystallographic orientation of the electrode surface, the adsorbate coverage and the electrode potential. In addition to typical interfacial water bands associated to perchlorate anions, which are co-adsorbed in order to compensate the positive charge of the ammonium group, the ATR-SEIRA spectra also show bands around 2950 cm −1 that can be related to the formation of hydrogen bonds between interfacial water and the ammonium group of the adsorbed zwitterion. The voltammetric experiments have shown that, as in the case of platinum electrodes, L-serine oxidizes at lower potentials than L-alanine. Under these conditions, the in situ infrared experiments show the formation of carbon dioxide and adsorbed cyanide as oxidation products of L-serine. In the case of L-alanine, only

  12. Design and synthesis of novel HDAC8 inhibitory 2,5-disubstituted-1,3,4-oxadiazoles containing glycine and alanine hybrids with anti cancer activity.

    Science.gov (United States)

    Pidugu, Vijaya Rao; Yarla, Nagendra Sastry; Pedada, Srinivasa Rao; Kalle, Arunasree M; Satya, A Krishna

    2016-11-01

    Oxadiazole is a heterocyclic compound containing an oxygen atom and two nitrogen atoms in a five-membered ring. Of the four oxadiazoles known, 1,3,4-oxadiazole has become an important structural motif for the development of new drugs and the compounds containing 1,3,4-oxadiazole cores have a broad spectrum of biological activity. Herein, we describe the design, synthesis and biological evaluation of a series of novel 2,5-disubstituted 1,3,4-oxadiazoles (10a-10j) as class I histone deacetylase (HDAC) inhibitors. The compounds were designed and evaluated for HDAC8 selectivity using in silico docking software (Glide) and the top 10 compounds with high dock score and obeying Lipinski's rule were synthesized organically. Further the biological HDAC inhibitory and selectivity assays and anti-proliferative assays were carried out. In in silico and in vitro studies, all compounds (10a-10j) showed significant HDAC inhibition and exhibited HDAC8 selectivity. Among all tested compounds, 10b showed substantial HDAC8 inhibitory activity and better anticancer activity which is comparable to the positive control, a FDA approved drug, vorinostat (SAHA). Structural activity relation is discussed with various substitutions in the benzene ring connected on 1,3,4-oxadizole and glycine/alanine. The study warranted further investigations to develop HDAC8-selective inhibitory molecule as a drug for neoplastic diseases. Novel 1,3,4-oxadizole substituted with glycine/alanine showed HDAC8 inhibition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Effects of Natural Fermentation on the Nutrient Composition of a ...

    African Journals Online (AJOL)

    BSN

    threonine, serine, proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine and phenylalanine were ... be processed to enhance voluntary intake ... effort was being made to simulate the .... the fermenting sample showed a.

  14. Oligomerization of glycine and alanine catalyzed by iron oxides: implications for prebiotic chemistry.

    Science.gov (United States)

    Shanker, Uma; Bhushan, Brij; Bhattacharjee, G; Kamaluddin

    2012-02-01

    Iron oxide minerals are probable constituents of the sediments present in geothermal regions of the primitive earth. They might have adsorbed different organic monomers (amino acids, nucleotides etc.) and catalyzed polymerization processes leading to the formation of the first living cell. In the present work we tested the catalytic activity of three forms of iron oxides (Goethite, Akaganeite and Hematite) in the intermolecular condensation of each of the amino acids glycine and L-alanine. The effect of zinc oxide and titanium dioxide on the oligomerization has also been studied. Oligomerization studies were performed for 35 days at three different temperatures 50, 90 and 120°C without applying drying/wetting cycling. The products formed were characterized by HPLC and ESI-MS techniques. All three forms of iron oxides catalyzed peptide bond formation (23.2% of gly2 and 10.65% of ala2). The reaction was monitored every 7 days. Formation of peptides was observed to start after 7 days at 50°C. Maximum yield of peptides was found after 35 days at 90°C. Reaction at 120°C favors formation of diketopiperazine derivatives. It is also important to note that after 35 days of reaction, goethite produced dimer and trimer with the highest yield among the oxides tested. We suggest that the activity of goethite could probably be due to its high surface area and surface acidity.

  15. Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis.

    Science.gov (United States)

    Li, Qingli; Lambrechts, Mark J; Zhang, Qiuyang; Liu, Sen; Ge, Dongxia; Yin, Rutie; Xi, Mingrong; You, Zongbing

    2013-01-01

    Glycine is a nonessential amino acid that is reversibly converted from serine intracellularly by serine hydroxymethyltransferase. Glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), are analogs to glycine, thus they may inhibit serine hydroxymethyltransferase to decrease intracellular glycine synthesis. In this study, we found that glyphosate and AMPA inhibited cell growth in eight human cancer cell lines but not in two immortalized human normal prostatic epithelial cell lines. AMPA arrested C4-2B and PC-3 cancer cells in the G1/G0 phase and inhibited entry into the S phase of the cell cycle. AMPA also promoted apoptosis in C4-2B and PC-3 cancer cell lines. AMPA upregulated p53 and p21 protein levels as well as procaspase 9 protein levels in C4-2B cells, whereas it downregulated cyclin D3 protein levels. AMPA also activated caspase 3 and induced cleavage of poly (adenosine diphosphate [ADP]-ribose) polymerase. This study provides the first evidence that glyphosate and AMPA can inhibit proliferation and promote apoptosis of cancer cells but not normal cells, suggesting that they have potentials to be developed into a new anticancer therapy.

  16. Predicting Three-Dimensional Conformations of Peptides Constructed of Only Glycine, Alanine, Aspartic Acid, and Valine

    Science.gov (United States)

    Oda, Akifumi; Fukuyoshi, Shuichi

    2015-06-01

    The GADV hypothesis is a form of the protein world hypothesis, which suggests that life originated from proteins (Lacey et al. 1999; Ikehara 2002; Andras 2006). In the GADV hypothesis, life is thought to have originated from primitive proteins constructed of only glycine, alanine, aspartic acid, and valine ([GADV]-proteins). In this study, the three-dimensional (3D) conformations of randomly generated short [GADV]-peptides were computationally investigated using replica-exchange molecular dynamics (REMD) simulations (Sugita and Okamoto 1999). Because the peptides used in this study consisted of only 20 residues each, they could not form certain 3D structures. However, the conformational tendencies of the peptides were elucidated by analyzing the conformational ensembles generated by REMD simulations. The results indicate that secondary structures can be formed in several randomly generated [GADV]-peptides. A long helical structure was found in one of the hydrophobic peptides, supporting the conjecture of the GADV hypothesis that many peptides aggregated to form peptide multimers with enzymatic activity in the primordial soup. In addition, these results indicate that REMD simulations can be used for the structural investigation of short peptides.

  17. Native Alanine Substitution in the Glycine Hinge Modulates Conformational Flexibility of Heme Nitric Oxide/Oxygen (H-NOX) Sensing Proteins.

    Science.gov (United States)

    Hespen, Charles W; Bruegger, Joel J; Guo, Yirui; Marletta, Michael A

    2018-06-15

    Heme nitric oxide/oxygen sensing (H-NOX) domains are direct NO sensors that regulate a variety of biological functions in both bacteria and eukaryotes. Previous work on H-NOX proteins has shown that upon NO binding, a conformational change occurs along two glycine residues on adjacent helices (termed the glycine hinge). Despite the apparent importance of the glycine hinge, it is not fully conserved in all H-NOX domains. Several H-NOX sensors from the family Flavobacteriaceae contain a native alanine substitution in one of the hinge residues. In this work, the effect of the increased steric bulk within the Ala-Gly hinge on H-NOX function was investigated. The hinge in Kordia algicida OT-1 ( Ka H-NOX) is composed of A71 and G145. Ligand-binding properties and signaling function for this H-NOX were characterized. The variant A71G was designed to convert the hinge region of Ka H-NOX to the typical Gly-Gly motif. In activity assays with its cognate histidine kinase (HnoK), the wild type displayed increased signal specificity compared to A71G. Increasing titrations of unliganded A71G gradually inhibits HnoK autophosphorylation, while increasing titrations of unliganded wild type H-NOX does not inhibit HnoK. Crystal structures of both wild type and A71G Ka H-NOX were solved to 1.9 and 1.6 Å, respectively. Regions of H-NOX domains previously identified as involved in protein-protein interactions with HnoK display significantly higher b-factors in A71G compared to wild-type H-NOX. Both biochemical and structural data indicate that the hinge region controls overall conformational flexibility of the H-NOX, affecting NO complex formation and regulation of its HnoK.

  18. Alterations in brain extracellular dopamine and glycine levels following combined administration of the glycine transporter type-1 inhibitor Org-24461 and risperidone.

    Science.gov (United States)

    Nagy, Katalin; Marko, Bernadett; Zsilla, Gabriella; Matyus, Peter; Pallagi, Katalin; Szabo, Geza; Juranyi, Zsolt; Barkoczy, Jozsef; Levay, Gyorgy; Harsing, Laszlo G

    2010-12-01

    The most dominant hypotheses for the pathogenesis of schizophrenia have focused primarily upon hyperfunctional dopaminergic and hypofunctional glutamatergic neurotransmission in the central nervous system. The therapeutic efficacy of all atypical antipsychotics is explained in part by antagonism of the dopaminergic neurotransmission, mainly by blockade of D(2) dopamine receptors. N-methyl-D-aspartate (NMDA) receptor hypofunction in schizophrenia can be reversed by glycine transporter type-1 (GlyT-1) inhibitors, which regulate glycine concentrations at the vicinity of NMDA receptors. Combined drug administration with D(2) dopamine receptor blockade and activation of hypofunctional NMDA receptors may be needed for a more effective treatment of positive and negative symptoms and the accompanied cognitive deficit in schizophrenia. To investigate this type of combined drug administration, rats were treated with the atypical antipsychotic risperidone together with the GlyT-1 inhibitor Org-24461. Brain microdialysis was applied in the striatum of conscious rats and determinations of extracellular dopamine, DOPAC, HVA, glycine, glutamate, and serine concentrations were carried out using HPLC/electrochemistry. Risperidone increased extracellular concentrations of dopamine but failed to influence those of glycine or glutamate measured in microdialysis samples. Org-24461 injection reduced extracellular dopamine concentrations and elevated extracellular glycine levels but the concentrations of serine and glutamate were not changed. When risperidone and Org-24461 were added in combination, a decrease in extracellular dopamine concentrations was accompanied with sustained elevation of extracellular glycine levels. Interestingly, the extracellular concentrations of glutamate were also enhanced. Our data indicate that coadministration of an antipsychotic with a GlyT-1 inhibitor may normalize hypofunctional NMDA receptor-mediated glutamatergic neurotransmission with reduced

  19. Reprogramming One-Carbon Metabolic Pathways To Decouple l-Serine Catabolism from Cell Growth in Corynebacterium glutamicum.

    Science.gov (United States)

    Zhang, Yun; Shang, Xiuling; Lai, Shujuan; Zhang, Yu; Hu, Qitiao; Chai, Xin; Wang, Bo; Liu, Shuwen; Wen, Tingyi

    2018-02-16

    l-Serine, the principal one-carbon source for DNA biosynthesis, is difficult for microorganisms to accumulate due to the coupling of l-serine catabolism and microbial growth. Here, we reprogrammed the one-carbon unit metabolic pathways in Corynebacterium glutamicum to decouple l-serine catabolism from cell growth. In silico model-based simulation showed a negative influence on glyA-encoding serine hydroxymethyltransferase flux with l-serine productivity. Attenuation of glyA transcription resulted in increased l-serine accumulation, and a decrease in purine pools, poor growth and longer cell shapes. The gcvTHP-encoded glycine cleavage (Gcv) system from Escherichia coli was introduced into C. glutamicum, allowing glycine-derived 13 CH 2 to be assimilated into intracellular purine synthesis, which resulted in an increased amount of one-carbon units. Gcv introduction not only restored cell viability and morphology but also increased l-serine accumulation. Moreover, comparative proteomic analysis indicated that abundance changes of the enzymes involved in one-carbon unit cycles might be responsible for maintaining one-carbon unit homeostasis. Reprogramming of the one-carbon metabolic pathways allowed cells to reach a comparable growth rate to accumulate 13.21 g/L l-serine by fed-batch fermentation in minimal medium. This novel strategy provides new insights into the regulation of cellular properties and essential metabolite accumulation by introducing an extrinsic pathway.

  20. The Glycerate and Phosphorylated Pathways of Serine Synthesis in Plants: The Branches of Plant Glycolysis Linking Carbon and Nitrogen Metabolism.

    Science.gov (United States)

    Igamberdiev, Abir U; Kleczkowski, Leszek A

    2018-01-01

    Serine metabolism in plants has been studied mostly in relation to photorespiration where serine is formed from two molecules of glycine. However, two other pathways of serine formation operate in plants and represent the branches of glycolysis diverging at the level of 3-phosphoglyceric acid. One branch (the glycerate - serine pathway) is initiated in the cytosol and involves glycerate formation from 3-phosphoglycerate, while the other (the phosphorylated serine pathway) operates in plastids and forms phosphohydroxypyruvate as an intermediate. Serine formed in these pathways becomes a precursor of glycine, formate and glycolate accumulating in stress conditions. The pathways can be linked to GABA shunt via transamination reactions and via participation of the same reductase for both glyoxylate and succinic semialdehyde. In this review paper we present a hypothesis of the regulation of redox balance in stressed plant cells via participation of the reactions associated with glycerate and phosphorylated serine pathways. We consider these pathways as important processes linking carbon and nitrogen metabolism and maintaining cellular redox and energy levels in stress conditions.

  1. Characterization and modelling of VanT: a novel, membrane-bound, serine racemase from vancomycin-resistant Enterococcus gallinarum BM4174.

    Science.gov (United States)

    Arias, C A; Martín-Martinez, M; Blundell, T L; Arthur, M; Courvalin, P; Reynolds, P E

    1999-03-01

    Sequence determination of a region downstream from the vanXYc gene in Enterococcus gallinarum BM4174 revealed an open reading frame, designated vanT, that encodes a 698-amino-acid polypeptide with an amino-terminal domain containing 10 predicted transmembrane segments. The protein contained a highly conserved pyridoxal phosphate attachment site in the C-terminal domain, typical of alanine racemases. The protein was overexpressed in Escherichia coli, and serine racemase activity was detected in the membrane but not in the cytoplasmic fraction after centrifugation of sonicated cells, whereas alanine racemase activity was located almost exclusively in the cytoplasm. When the protein was overexpressed as a polypeptide lacking the predicted transmembrane domain, serine racemase activity was detected in the cytoplasm. The serine racemase activity was partially (64%) inhibited by D-cycloserine, whereas host alanine racemase activity was almost totally inhibited (97%). Serine racemase activity was also detected in membrane preparations of constitutively vancomycin-resistant E. gallinarum BM4174 but not in BM4175, in which insertional inactivation of the vanC-1 D-Ala:D-Ser ligase gene probably had a polar effect on expression of the vanXYc and vanT genes. Comparative modelling of the deduced C-terminal domain was based on the alignment of VanT with the Air alanine racemase from Bacillus stearothermophilus. The model revealed that almost all critical amino acids in the active site of Air were conserved in VanT, indicating that the C-terminal domain of VanT is likely to adopt a three-dimensional structure similar to that of Air and that the protein could exist as a dimer. These results indicate that the source of D-serine for peptidoglycan synthesis in vancomycin-resistant enterococci expressing the VanC phenotype involves racemization of L- to D-serine by a membrane-bound serine racemase.

  2. SHMT2 drives glioma cell survival in ischaemia but imposes a dependence on glycine clearance.

    Science.gov (United States)

    Kim, Dohoon; Fiske, Brian P; Birsoy, Kivanc; Freinkman, Elizaveta; Kami, Kenjiro; Possemato, Richard L; Chudnovsky, Yakov; Pacold, Michael E; Chen, Walter W; Cantor, Jason R; Shelton, Laura M; Gui, Dan Y; Kwon, Manjae; Ramkissoon, Shakti H; Ligon, Keith L; Kang, Seong Woo; Snuderl, Matija; Vander Heiden, Matthew G; Sabatini, David M

    2015-04-16

    Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumour microenvironment. Here we identify a key role for serine and glycine metabolism in the survival of brain cancer cells within the ischaemic zones of gliomas. In human glioblastoma multiforme, mitochondrial serine hydroxymethyltransferase (SHMT2) and glycine decarboxylase (GLDC) are highly expressed in the pseudopalisading cells that surround necrotic foci. We find that SHMT2 activity limits that of pyruvate kinase (PKM2) and reduces oxygen consumption, eliciting a metabolic state that confers a profound survival advantage to cells in poorly vascularized tumour regions. GLDC inhibition impairs cells with high SHMT2 levels as the excess glycine not metabolized by GLDC can be converted to the toxic molecules aminoacetone and methylglyoxal. Thus, SHMT2 is required for cancer cells to adapt to the tumour environment, but also renders these cells sensitive to glycine cleavage system inhibition.

  3. Multifarious Beneficial Effect of Nonessential Amino Acid, Glycine: A Review

    Directory of Open Access Journals (Sweden)

    Meerza Abdul Razak

    2017-01-01

    Full Text Available Glycine is most important and simple, nonessential amino acid in humans, animals, and many mammals. Generally, glycine is synthesized from choline, serine, hydroxyproline, and threonine through interorgan metabolism in which kidneys and liver are the primarily involved. Generally in common feeding conditions, glycine is not sufficiently synthesized in humans, animals, and birds. Glycine acts as precursor for several key metabolites of low molecular weight such as creatine, glutathione, haem, purines, and porphyrins. Glycine is very effective in improving the health and supports the growth and well-being of humans and animals. There are overwhelming reports supporting the role of supplementary glycine in prevention of many diseases and disorders including cancer. Dietary supplementation of proper dose of glycine is effectual in treating metabolic disorders in patients with cardiovascular diseases, several inflammatory diseases, obesity, cancers, and diabetes. Glycine also has the property to enhance the quality of sleep and neurological functions. In this review we will focus on the metabolism of glycine in humans and animals and the recent findings and advances about the beneficial effects and protection of glycine in different disease states.

  4. A cation-π interaction at a phenylalanine residue in the glycine receptor binding site is conserved for different agonists

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Hanek, Ariele P; Price, Kerry L

    2011-01-01

    . In the current study, we investigated whether the lower efficacy agonists of the human GlyR β-alanine and taurine also form cation-π interactions with Phe159. By incorporating a series of unnatural amino acids, we found cation-π interactions between Phe159 and the amino groups of β-alanine and taurine....... The strengths of these interactions were significantly weaker than for glycine. Modeling studies suggest that β-alanine and taurine are orientated subtly differently in the binding pocket, with their amino groups further from Phe159 than that of glycine. These data therefore show that similar agonists can have...... similar but not identical orientations and interactions in the binding pocket and provide a possible explanation for the lower potencies of β-alanine and taurine....

  5. Production of 1-carbon units from glycine is extensive in healthy men and women.

    Science.gov (United States)

    Lamers, Yvonne; Williamson, Jerry; Theriaque, Douglas W; Shuster, Jonathan J; Gilbert, Lesa R; Keeling, Christine; Stacpoole, Peter W; Gregory, Jesse F

    2009-04-01

    Glycine undergoes decarboxylation in the glycine cleavage system (GCS) to yield CO(2), NH(3), and a 1-carbon unit. CO(2) also can be generated from the 2-carbon of glycine by 10-formyltetrahydrofolate-dehydrogenase and, after glycine-to-serine conversion by serine hydroxymethyltransferase, from the tricarboxylic acid cycle. To evaluate the relative fates of glycine carbons in CO(2) generation in healthy volunteers (3 male, 3 female, aged 21-26 y), primed, constant infusions were conducted using 9.26 micromol x h(-1) x kg(-1) of [1,2-(13)C]glycine and 1.87 micromol x h(-1) x kg(-1) of [5,5,5-(2)H(3)]leucine, followed by an infusion protocol using [1-(13)C]glycine as the glycine tracer. The time period between the infusion protocols was >6 mo. In vivo rates of whole-body glycine and leucine flux were nearly identical in protocols with [1,2-(13)C]glycine and [5,5,5-(2)H(3)]leucine and with [1-(13)C]glycine and [5,5,5-(2)H(3)]leucine tracers, which showed high reproducibility between the tracer protocols. Using the [1-(13)C]glycine tracer, breath CO(2) data showed a total rate of glycine decarboxylation of 96 +/- 8 micromol x h(-1) x kg(-1), which was 22 +/- 3% of whole-body glycine flux. In contrast, infusion of [1,2-(13)C]glycine yielded a glycine-to-CO(2) flux of 146 +/- 37 micromol x h(-1) x kg(-1) (P = 0.026). By difference, this implies a rate of CO(2) formation from the glycine 2-carbon of 51 +/- 40 micromol x h(-1) x kg(-1), which accounts for approximately 35% of the total CO(2) generated in glycine catabolism. These findings also indicate that approximately 65% of the CO(2) generation from glycine occurs by decarboxylation, primarily from the GCS. Further, these results suggest that the GCS is responsible for the entry of 5,10-methylenetetrahydrofolate into 1-carbon metabolism at a very high rate ( approximately 96 micromol x h(-1) x kg(-1)), which is approximately 20 times the demand for methyl groups for homocysteine remethylation.

  6. Amino acids in biofilm material on aluminium panels immersed in marine waters

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Wagh, A.B.

    .63 to 52.04% of the total ON of the SPM. Aspartic acid, glycine, alanine, serine, leucine and lysine and glutamic acid were the most abundant individual amino acids in both the biofilm material and the SPM. THe distribution of individual amino acids...

  7. Magnitude of a conformational change in the glycine receptor beta1-beta2 loop is correlated with agonist efficacy

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Lynch, Joseph W

    2009-01-01

    associated with the closed-flip transition in the alpha1-glycine receptor. We employed voltage-clamp fluorometry to compare ligand-binding domain conformational changes induced by the following agonists, listed from highest to lowest affinity and efficacy: glycine > beta-alanine > taurine. Voltage...

  8. Effect of dipotassium hydrogen phosphate on thermodynamic properties of glycine and L-alanine in aqueous solutions at different temperatures

    International Nuclear Information System (INIS)

    Kumar, Harsh; Kaur, Kirtanjot

    2012-01-01

    Highlights: ► Densities and speeds of sound of amino acids in DKHP. ► Apparent molar volume and apparent molar compressibilities were calculated. ► The partial molar expansibilities at infinite dilution φ E 0 were obtained. ► Hydration number n H was calculated. ► The results are discussed in terms of solute–solvent interactions. - Abstract: Densities, ρ, speed of sound, u for glycine, L-alanine have been measured in aqueous solutions of dipotassium hydrogen phosphate (DKHP) ranging from 0.2, 0.4, 0.6 and 0.8 mol·kg −1 at temperatures T = (288.15, 298.15, 308.15 and 318.15) K. The different parameters such as apparent molar volume, limiting apparent molar volume, transfer volume, partial molar expansibility have been derived from density data. Experimental speeds of sound data were used to estimate apparent molar adiabatic compressibility, limiting apparent molar adiabatic compressibility, transfer parameter and hydration number. These parameters have been discussed in the light of ion-ion and ion-solvent interactions.

  9. Protein kinase A phosphorylates serine 267 in the homeodomain of engrailed-2 leading to decreased DNA binding

    DEFF Research Database (Denmark)

    Hjerrild, Majbrit; Stensballe, Allan; Jensen, Ole N

    2004-01-01

    Engrailed-2 (En-2) belongs to an evolutionarily conserved family of DNA binding homeodomain-containing proteins that are expressed in mammalian brain during development. Here, we demonstrate that serine 267 in the homeodomain of En-2 is phosphorylated by protein kinase A (PKA) in forskolin......-treated COS-7 cells. Furthermore, we analyze the physiological function of En-2 phosphorylation by PKA. The nuclear localization of En-2 is not influenced by the phosphorylation of serine 267. However, substitution of serine 267 with alanine resulted in increased binding of En-2 to DNA, while replacing serine...

  10. Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis

    Directory of Open Access Journals (Sweden)

    Li Q

    2013-07-01

    Full Text Available Qingli Li,1,2 Mark J Lambrechts,1 Qiuyang Zhang,1 Sen Liu,1 Dongxia Ge,1 Rutie Yin,2 Mingrong Xi,2 Zongbing You1 1Departments of Structural and Cellular Biology and Orthopaedic Surgery, Tulane Cancer Center and Louisiana Cancer Research Consortium, Tulane Center for Stem Cell Research and Regenerative Medicine, and Tulane Center for Aging, Tulane University Health Sciences Center, New Orleans, LA, USA; 2Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, People’s Republic of China Abstract: Glycine is a nonessential amino acid that is reversibly converted from serine intracellularly by serine hydroxymethyltransferase. Glyphosate and its degradation product, aminomethylphosphonic acid (AMPA, are analogs to glycine, thus they may inhibit serine hydroxymethyltransferase to decrease intracellular glycine synthesis. In this study, we found that glyphosate and AMPA inhibited cell growth in eight human cancer cell lines but not in two immortalized human normal prostatic epithelial cell lines. AMPA arrested C4-2B and PC-3 cancer cells in the G1/G0 phase and inhibited entry into the S phase of the cell cycle. AMPA also promoted apoptosis in C4-2B and PC-3 cancer cell lines. AMPA upregulated p53 and p21 protein levels as well as procaspase 9 protein levels in C4-2B cells, whereas it downregulated cyclin D3 protein levels. AMPA also activated caspase 3 and induced cleavage of poly (adenosine diphosphate [ADP]-ribose polymerase. This study provides the first evidence that glyphosate and AMPA can inhibit proliferation and promote apoptosis of cancer cells but not normal cells, suggesting that they have potentials to be developed into a new anticancer therapy. Keywords: serine hydroxymethyltransferase, prostate cancer, apoptosis

  11. SHMT2 drives glioma cell survival in the tumor microenvironment but imposes a dependence on glycine clearance

    Science.gov (United States)

    Kim, Dohoon; Fiske, Brian P.; Birsoy, Kivanc; Freinkman, Elizaveta; Kami, Kenjiro; Possemato, Richard; Chudnovsky, Yakov; Pacold, Michael E.; Chen, Walter W.; Cantor, Jason R.; Shelton, Laura M.; Gui, Dan Y.; Kwon, Manjae; Ramkissoon, Shakti H.; Ligon, Keith L.; Kang, Seong Woo; Snuderl, Matija; Heiden, Matthew G. Vander; Sabatini, David M.

    2015-01-01

    SUMMARY Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumor microenvironment1–3. Here, we identify a key role for serine and glycine metabolism in the survival of brain cancer cells within the ischemic zones of gliomas. In human glioblastoma multiforme (GBM), mitochondrial serine hydroxymethyltransferase (SHMT2) and glycine decarboxylase (GLDC) are highly expressed in the pseudopalisading cells that surround necrotic foci. We find that SHMT2 activity limits that of pyruvate kinase (PKM2) and reduces oxygen consumption, eliciting a metabolic state that confers a profound survival advantage to cells in poorly vascularized tumor regions. GLDC inhibition impairs cells with high SHMT2 levels as the excess glycine not metabolized by GLDC can be converted to the toxic molecules aminoacetone and methylglyoxal. Thus, SHMT2 is required for cancer cells to adapt to the tumor environment, but also renders these cells sensitive to glycine cleavage system inhibition. PMID:25855294

  12. Quantitative evaluation of the biosynthetic pathways leading to δ-aminolevulinic acid from the Shemin precursor glycine via the C5 pathway in Arthrobacter hyalinus by analysis of 13C-labeled coproporphyrinogen III biosynthesized from [2-13C]glycine, [1-13C]acetate, and [2-13C]acetate using 13C NMR spectroscopy

    International Nuclear Information System (INIS)

    Katsumi Iida

    2013-01-01

    The biosynthetic pathways leading to δ-aminolevulinic acid (ALA) from the Shemin precursor glycine via the C5 pathway in Arthrobacter hyalinus were quantitatively evaluated by means of feeding experiments with [2- 13 C]glycine, sodium [1- 13 C]acetate, and sodium [2- 13 C]acetate, followed by analysis of the labeling patterns of coproporphyrinogen III (Copro'gen III) (biosynthesized from ALA) using 13 C NMR spectroscopy. Two biosynthetic pathways leading to ALA from glycine via the C5 pathway were identified: i.e., transformation of glycine to l-serine catalyzed by glycine hydroxymethyltransferase, and glycine synthase-catalyzed catabolism of glycine to N 5 , N 10 -methylene-tetrahydrofolic acid (THF), which reacts with another molecule of glycine to afford l-serine. l-Serine is transformed to acetyl-CoA via pyruvic acid. Acetyl-CoA enters the tricarboxylic acid cycle, affording 2-oxoglutaric acid, which in turn is transformed to l-glutamic acid. The l-glutamic acid enters the C5 pathway, affording ALA in A. hyalinus. A 13 C NMR spectroscopic comparison of the labeling patterns of Copro'gen III obtained after feeding of [2- 13 C]glycine, sodium [1- 13 C]acetate, and sodium [2- 13 C]acetate showed that [2- 13 C]glycine transformation and [2- 13 C]glycine catabolism in A. hyalinus proceed in the ratio of 52 and 48 %. The reaction of [2- 13 C]glycine and N 5 , N 10 -methylene-THF, that of glycine and N 5 , N 10 -[methylene- 13 C]methylene-THF generated from the [2- 13 C]glycine catabolism, and that of [2- 13 C]glycine and N 5 , N 10 -[methylene- 13 C]methylene-THF transformed the fed [2- 13 C]glycine to [1- 13 C]acetyl-CoA, [2- 13 C]acetyl-CoA, and [1,2- 13 C 2 ]acetyl-CoA in the ratios of 42, 37, and 21 %, respectively. These labeled acetyl-CoAs were then incorporated into ALA. Our results provide a quantitative picture of the pathways of biosynthetic transformation to ALA from glycine in A. hyalinus. (author)

  13. Structural and functional importance of transmembrane domain 3 (TM3) in the aspartate:alanine antiporter AspT: topology and function of the residues of TM3 and oligomerization of AspT.

    Science.gov (United States)

    Nanatani, Kei; Maloney, Peter C; Abe, Keietsu

    2009-04-01

    AspT, the aspartate:alanine antiporter of Tetragenococcus halophilus, a membrane protein of 543 amino acids with 10 putative transmembrane (TM) helices, is the prototype of the aspartate:alanine exchanger (AAE) family of transporters. Because TM3 (isoleucine 64 to methionine 85) has many amino acid residues that are conserved among members of the AAE family and because TM3 contains two charged residues and four polar residues, it is thought to be located near (or to form part of) the substrate translocation pathway that includes the binding site for the substrates. To elucidate the role of TM3 in the transport process, we carried out cysteine-scanning mutagenesis. The substitutions of tyrosine 75 and serine 84 had the strongest inhibitory effects on transport (initial rates of l-aspartate transport were below 15% of the rate for cysteine-less AspT). Considerable but less-marked effects were observed upon the replacement of methionine 70, phenylalanine 71, glycine 74, arginine 76, serine 83, and methionine 85 (initial rates between 15% and 30% of the rate for cysteine-less AspT). Introduced cysteine residues at the cytoplasmic half of TM3 could be labeled with Oregon green maleimide (OGM), whereas cysteines close to the periplasmic half (residues 64 to 75) were not labeled. These results suggest that TM3 has a hydrophobic core on the periplasmic half and that hydrophilic residues on the cytoplasmic half of TM3 participate in the formation of an aqueous cavity in membranes. Furthermore, the presence of l-aspartate protected the cysteine introduced at glycine 62 against a reaction with OGM. In contrast, l-aspartate stimulated the reactivity of the cysteine introduced at proline 79 with OGM. These results demonstrate that TM3 undergoes l-aspartate-induced conformational alterations. In addition, nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses and a glutaraldehyde cross-linking assay suggest that functional AspT forms homo-oligomers as a

  14. Structural and Functional Importance of Transmembrane Domain 3 (TM3) in the Aspartate:Alanine Antiporter AspT: Topology and Function of the Residues of TM3 and Oligomerization of AspT▿

    Science.gov (United States)

    Nanatani, Kei; Maloney, Peter C.; Abe, Keietsu

    2009-01-01

    AspT, the aspartate:alanine antiporter of Tetragenococcus halophilus, a membrane protein of 543 amino acids with 10 putative transmembrane (TM) helices, is the prototype of the aspartate:alanine exchanger (AAE) family of transporters. Because TM3 (isoleucine 64 to methionine 85) has many amino acid residues that are conserved among members of the AAE family and because TM3 contains two charged residues and four polar residues, it is thought to be located near (or to form part of) the substrate translocation pathway that includes the binding site for the substrates. To elucidate the role of TM3 in the transport process, we carried out cysteine-scanning mutagenesis. The substitutions of tyrosine 75 and serine 84 had the strongest inhibitory effects on transport (initial rates of l-aspartate transport were below 15% of the rate for cysteine-less AspT). Considerable but less-marked effects were observed upon the replacement of methionine 70, phenylalanine 71, glycine 74, arginine 76, serine 83, and methionine 85 (initial rates between 15% and 30% of the rate for cysteine-less AspT). Introduced cysteine residues at the cytoplasmic half of TM3 could be labeled with Oregon green maleimide (OGM), whereas cysteines close to the periplasmic half (residues 64 to 75) were not labeled. These results suggest that TM3 has a hydrophobic core on the periplasmic half and that hydrophilic residues on the cytoplasmic half of TM3 participate in the formation of an aqueous cavity in membranes. Furthermore, the presence of l-aspartate protected the cysteine introduced at glycine 62 against a reaction with OGM. In contrast, l-aspartate stimulated the reactivity of the cysteine introduced at proline 79 with OGM. These results demonstrate that TM3 undergoes l-aspartate-induced conformational alterations. In addition, nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses and a glutaraldehyde cross-linking assay suggest that functional AspT forms homo-oligomers as a

  15. Energetics of the molecular interactions of L-alanine and L-serine with xylitol, D-sorbitol, and D-mannitol in aqueous solutions at 298.15 K

    Science.gov (United States)

    Mezhevoi, I. N.; Badelin, V. G.

    2013-04-01

    Integral enthalpies of dissolution Δsol H m of L-alanine and L-serine are measured via the calorimetry of dissolution in aqueous solutions of xylitol, D-sorbitol, and D-mannitol. Standard enthalpies of dissolution (Δsol H ○) and the transfer (Δtr H ○) of amino acids from water to binary solvent are calculated from the experimental data. Using the McMillan-Mayer theory, enthalpy coefficients of pairwise interactions h xy of amino acids with molecules of polyols are calculated that are negative. The obtained results are discussed within the theory of the prevalence of different types of interactions in mixed solutions and the effect of the structural features of interacting biomolecules on the thermochemical parameters of dissolution of amino acids.

  16. Generation of serine/threonine check points in HN(C)N spectra

    Indian Academy of Sciences (India)

    Administrator

    ing to generate alanine. 6 and serine/threonine specific peak patterns. 7 have enhanced the speed of assign- ment quite substantially. These developments involved a simple modification to the pulse sequence. Continuing such efforts for rapid resonance as- signments, we have implemented here the tuning ideas.

  17. General synthesis of C-glycosyl amino acids via proline-catalyzed direct electrophilic alpha-amination of C-glycosylalkyl aldehydes.

    Science.gov (United States)

    Nuzzi, Andrea; Massi, Alessandro; Dondoni, Alessandro

    2008-10-16

    Non-natural axially and equatorially linked C-glycosyl alpha-amino acids (glycines, alanines, and CH2-serine isosteres) with either S or R alpha-configuration were prepared by D- and L-proline-catalyzed (de >95%) alpha-amination of C-glycosylalkyl aldehydes using dibenzyl azodicarboxylate as the electrophilic reagent.

  18. Decreased levels of free D-aspartic acid in the forebrain of serine racemase (Srr) knock-out mice.

    Science.gov (United States)

    Horio, Mao; Ishima, Tamaki; Fujita, Yuko; Inoue, Ran; Mori, Hisashi; Hashimoto, Kenji

    2013-05-01

    d-Serine, an endogenous co-agonist of the N-methyl-d-aspartate (NMDA) receptor is synthesized from l-serine by serine racemase (SRR). A previous study of Srr knockout (Srr-KO) mice showed that levels of d-serine in forebrain regions, such as frontal cortex, hippocampus, and striatum, but not cerebellum, of mutant mice are significantly lower than those of wild-type (WT) mice, suggesting that SRR is responsible for d-serine production in the forebrain. In this study, we attempted to determine whether SRR affects the level of other amino acids in brain tissue. We found that tissue levels of d-aspartic acid in the forebrains (frontal cortex, hippocampus and striatum) of Srr-KO mice were significantly lower than in WT mice, whereas levels of d-aspartic acid in the cerebellum were not altered. Levels of d-alanine, l-alanine, l-aspartic acid, taurine, asparagine, arginine, threonine, γ-amino butyric acid (GABA) and methionine, remained the same in frontal cortex, hippocampus, striatum and cerebellum of WT and mutant mice. Furthermore, no differences in d-aspartate oxidase (DDO) activity were detected in the forebrains of WT and Srr-KO mice. These results suggest that SRR and/or d-serine may be involved in the production of d-aspartic acid in mouse forebrains, although further detailed studies will be necessary to confirm this finding. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Application of Glycine-TTC dosimeter in gamma radiation processing facility

    International Nuclear Information System (INIS)

    Shinde, S.H.; Mondal, S.; Kulkarni, M.S.

    2018-01-01

    Glycine-TTC dosimeter was found to have a useful dose range of 5 to 30 kGy using spectro-photometric read-out method. Potential use of this dosimeter was demonstrated by measuring dose-rate in gamma chamber GC 900. The aim of the present study was to verify the performance of this dosimeter in actual industrial processing conditions encountered in radiation processing facility such as Gamma Radiation Processing Plant for Spices (GRPPS), BRIT, Vashi. Accordingly, glycine-TTC dosimeters were irradiated along with routine dosimeter viz. ceric-cerous of GRPPS and reference standard dosimeter viz. alanine EPR

  20. Interactions of glycine, L-alanine and L-valine with aqueous solutions of trisodium citrate at different temperatures: A volumetric and acoustic approach

    International Nuclear Information System (INIS)

    Kumar, Harsh; Singla, Meenu; Jindal, Rajeev

    2013-01-01

    Highlights: • Densities and speeds of sound of amino acids in aqueous trisodium citrate. • Positive values of transfer volume indicates interactions between ions of amino acids and TSC. • Ion–hydrophilic and hydrophilic–hydrophilic interactions are present. • Pair-wise interactions are dominant in the mixtures. -- Abstract: Densities, ρ, and speed of sound, u for glycine, L-alanine and L-valine in (0.2, 0.4, 0.6, and 0.8) mol · kg −1 aqueous solutions of trisodium citrate at T = (288.15, 298.15, 308.15 and 318.15) K have been measured. The different parameters such as apparent molar volume, limiting apparent molar volume, transfer volume, have been derived from density data. Experimental values of the speed of sound were used to estimate apparent molar apparent molar isentropic compression, limiting apparent molar isentropic compression, and transfer parameter. The pair and triplet interaction coefficient have been calculated from transfer parameters

  1. L-Glycine Alleviates Furfural-Induced Growth Inhibition during Isobutanol Production in Escherichia coli.

    Science.gov (United States)

    Song, Hun-Suk; Jeon, Jong-Min; Choi, Yong Keun; Kim, Jun-Young; Kim, Wooseong; Yoon, Jeong-Jun; Park, Kyungmoon; Ahn, Jungoh; Lee, Hongweon; Yang, Yung-Hun

    2017-12-28

    Lignocellulose is now a promising raw material for biofuel production. However, the lignin complex and crystalline cellulose require pretreatment steps for breakdown of the crystalline structure of cellulose for the generation of fermentable sugars. Moreover, several fermentation inhibitors are generated with sugar compounds, majorly furfural. The mitigation of these inhibitors is required for the further fermentation steps to proceed. Amino acids were investigated on furfural-induced growth inhibition in E. coli producing isobutanol. Glycine and serine were the most effective compounds against furfural. In minimal media, glycine conferred tolerance against furfural. From the IC₅₀ value for inhibitors in the production media, only glycine could alleviate growth arrest for furfural, where 6 mM glycine addition led to a slight increase in growth rate and isobutanol production from 2.6 to 2.8 g/l under furfural stress. Overexpression of glycine pathway genes did not lead to alleviation. However, addition of glycine to engineered strains blocked the growth arrest and increased the isobutanol production about 2.3-fold.

  2. Contribution of the D-Serine-dependent pathway to the cellular mechanisms underlying cognitive aging

    Directory of Open Access Journals (Sweden)

    Emilie Rouaud

    2010-02-01

    Full Text Available An association between age-related memory impairments and changes in functional plasticity in the aging brain has been under intense study within the last decade. In this article, we show that an impaired activation of the strychnine-insensitive glycine site of N-Methyl-D-Aspartate receptors (NMDA-R by its agonist D-serine contributes to deficits of synaptic plasticity in the hippocampus of memory-impaired aged rats. Supplementation with exogenous D-serine prevents the age-related deficits of isolated NMDA-R-dependent synaptic potentials as well as those of theta-burst-induced long-term potentiation and synaptic depotentiation. Endogenous levels of D-serine are reduced in the hippocampus with aging, that correlates with a weaker expression of serine racemase synthesizing the amino acid. On the contrary, the affinity of D-serine binding to NMDA-R is not affected by aging. These results point to a critical role for the D-serine-dependent pathway in the functional alterations of the brain underlying memory impairment and provide key information in the search for new therapeutic strategies for the treatment of memory deficits in the elderly.

  3. Chromatin-Bound MDM2 Regulates Serine Metabolism and Redox Homeostasis Independently of p53.

    Science.gov (United States)

    Riscal, Romain; Schrepfer, Emilie; Arena, Giuseppe; Cissé, Madi Y; Bellvert, Floriant; Heuillet, Maud; Rambow, Florian; Bonneil, Eric; Sabourdy, Frédérique; Vincent, Charles; Ait-Arsa, Imade; Levade, Thierry; Thibaut, Pierre; Marine, Jean-Christophe; Portais, Jean-Charles; Sarry, Jean-Emmanuel; Le Cam, Laurent; Linares, Laetitia K

    2016-06-16

    The mouse double minute 2 (MDM2) oncoprotein is recognized as a major negative regulator of the p53 tumor suppressor, but growing evidence indicates that its oncogenic activities extend beyond p53. Here, we show that MDM2 is recruited to chromatin independently of p53 to regulate a transcriptional program implicated in amino acid metabolism and redox homeostasis. Identification of MDM2 target genes at the whole-genome level highlights an important role for ATF3/4 transcription factors in tethering MDM2 to chromatin. MDM2 recruitment to chromatin is a tightly regulated process that occurs during oxidative stress and serine/glycine deprivation and is modulated by the pyruvate kinase M2 (PKM2) metabolic enzyme. Depletion of endogenous MDM2 in p53-deficient cells impairs serine/glycine metabolism, the NAD(+)/NADH ratio, and glutathione (GSH) recycling, impacting their redox state and tumorigenic potential. Collectively, our data illustrate a previously unsuspected function of chromatin-bound MDM2 in cancer cell metabolism. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. SHMT2 drives glioma cell survival in ischaemia but imposes a dependence on glycine clearance.

    NARCIS (Netherlands)

    Kim, D.; Fiske, B.P.; Birsoy, K.; Freinkman, E.; Kami, K.; Possemato, R.L.; Chudnovsky, Y.; Pacold, M.E.; Chen, W.W.; Cantor, J.R.; Shelton, L.M.; Gui, D.Y.; Kwon, M.; Ramkissoon, S.H.; Ligon, K.L.; Kang, S.W.; Snuderl, M.; der Heiden, M.G. Van; Sabatini, D.M.

    2015-01-01

    Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumour microenvironment. Here we identify a key role for serine and glycine metabolism in the survival of brain

  5. Effect of glycine, DL-alanine and DL-2-aminobutyric acid on the temperature of maximum density of water

    International Nuclear Information System (INIS)

    Romero, Carmen M.; Torres, Andres Felipe

    2015-01-01

    Highlights: • Effect of α-amino acids on the temperature of maximum density of water is presented. • The addition of α-amino acids decreases the temperature of maximum density of water. • Despretz constants suggest that the amino acids behave as water structure breakers. • Despretz constants decrease as the number of CH 2 groups of the amino acid increase. • Solute disrupting effect becomes smaller as its hydrophobic character increases. - Abstract: The effect of glycine, DL-alanine and DL-2-aminobutyric acid on the temperature of maximum density of water was determined from density measurements using a magnetic float densimeter. Densities of aqueous solutions were measured within the temperature range from T = (275.65 to 278.65) K at intervals of T = 0.50 K over the concentration range between (0.0300 and 0.1000) mol · kg −1 . A linear relationship between density and concentration was obtained for all the systems in the temperature range considered. The temperature of maximum density was determined from the experimental results. The effect of the three amino acids is to decrease the temperature of maximum density of water and the decrease is proportional to molality according to Despretz equation. The effect of the amino acids on the temperature of maximum density decreases as the number of methylene groups of the alkyl chain becomes larger. The results are discussed in terms of (solute + water) interactions and the effect of amino acids on water structure

  6. Protein Homeostasis Defects of Alanine-Glyoxylate Aminotransferase: New Therapeutic Strategies in Primary Hyperoxaluria Type I

    Directory of Open Access Journals (Sweden)

    Angel L. Pey

    2013-01-01

    Full Text Available Alanine-glyoxylate aminotransferase catalyzes the transamination between L-alanine and glyoxylate to produce pyruvate and glycine using pyridoxal 5′-phosphate (PLP as cofactor. Human alanine-glyoxylate aminotransferase is a peroxisomal enzyme expressed in the hepatocytes, the main site of glyoxylate detoxification. Its deficit causes primary hyperoxaluria type I, a rare but severe inborn error of metabolism. Single amino acid changes are the main type of mutation causing this disease, and considerable effort has been dedicated to the understanding of the molecular consequences of such missense mutations. In this review, we summarize the role of protein homeostasis in the basic mechanisms of primary hyperoxaluria. Intrinsic physicochemical properties of polypeptide chains such as thermodynamic stability, folding, unfolding, and misfolding rates as well as the interaction of different folding states with protein homeostasis networks are essential to understand this disease. The view presented has important implications for the development of new therapeutic strategies based on targeting specific elements of alanine-glyoxylate aminotransferase homeostasis.

  7. The Nitrogen Moieties of Dietary Nonessential Amino Acids Are Distinctively Metabolized in the Gut and Distributed to the Circulation in Rats.

    Science.gov (United States)

    Nakamura, Hidehiro; Kawamata, Yasuko; Kuwahara, Tomomi; Sakai, Ryosei

    2017-08-01

    Background: Although previous growth studies in rodents have indicated the importance of dietary nonessential amino acids (NEAAs) as nitrogen sources, individual NEAAs have different growth-promoting activities. This phenomenon might be attributable to differences in the nitrogen metabolism of individual NEAAs. Objective: The aim of this study was to compare nitrogen metabolism across dietary NEAAs with the use of their 15 N isotopologues. Methods: Male Fischer rats (8 wk old) were given 1.0 g amino acid-defined diets containing either 15 N-labeled glutamate, glutamine (amino or amide), aspartate, alanine, proline, glycine, or serine hourly for 5-6 h. Then, steady-state amino acid concentrations and their 15 N enrichments in the gut and in portal and arterial plasma were measured by an amino acid analyzer and LC tandem mass spectrometry, respectively. Results: The intestinal 15 N distribution and portal-arterial balance of 15 N metabolites indicated that most dietary glutamate nitrogen (>90% of dietary input) was incorporated into various amino acids, including alanine, proline, and citrulline, in the gut. Dietary aspartate nitrogen, alanine nitrogen, and amino nitrogen of glutamine were distributed similarly to other amino acids both in the gut and in the circulation. In contrast, incorporation of the nitrogen moieties of dietary proline, serine, and glycine into other amino acids was less than that of other NEAAs, although interconversion between serine and glycine was very active. Cluster analysis of 15 N enrichment data also indicated that dietary glutamate nitrogen, aspartate nitrogen, alanine nitrogen, and the amino nitrogen of glutamine were distributed similarly to intestinal and circulating amino acids. Further, the analysis revealed close relations between intestinal and arterial 15 N enrichment for each amino acid. The steady-state 15 N enrichment of arterial amino acids indicated that substantial amounts of circulating amino acid nitrogen are derived

  8. Substrate specificity of the aspartate:alanine antiporter (AspT) of Tetragenococcus halophilus in reconstituted liposomes.

    Science.gov (United States)

    Sasahara, Ayako; Nanatani, Kei; Enomoto, Masaru; Kuwahara, Shigefumi; Abe, Keietsu

    2011-08-19

    The aspartate:alanine antiporter (AspT) of the lactic acid bacterium Tetragenococcus halophilus is a member of the aspartate:alanine exchanger (AAEx) transporter family. T. halophilus AspT catalyzes the electrogenic exchange of L-aspartate(1-) with L-alanine(0). Although physiological functions of AspT were well studied, L-aspartate(1-):L-alanine(0) antiport mechanisms are still unsolved. Here we report that the binding sites of L-aspartate and L-alanine are independently present in AspT by means of the kinetic studies. We purified His(6)-tagged T. halophilus AspT and characterized its kinetic properties when reconstituted in liposomes (K(m) = 0.35 ± 0.03 mm for L-aspartate, K(m) = 0.098 ± 0 mm for D-aspartate, K(m) = 26 ± 2 mm for L-alanine, K(m) = 3.3 ± 0.2 mm for D-alanine). Competitive inhibition by various amino acids of L-aspartate or L-alanine in self-exchange reactions revealed that L-cysteine selectively inhibited L-aspartate self-exchange but only weakly inhibited L-alanine self-exchange. Additionally, L-serine selectively inhibited L-alanine self-exchange but barely inhibited L-aspartate self-exchange. The aspartate analogs L-cysteine sulfinic acid, L-cysteic acid, and D-cysteic acid competitively and strongly inhibited L-aspartate self-exchange compared with L-alanine self-exchange. Taken together, these kinetic data suggest that the putative binding sites of L-aspartate and L-alanine are independently located in the substrate translocation pathway of AspT.

  9. Substrate Specificity of the Aspartate:Alanine Antiporter (AspT) of Tetragenococcus halophilus in Reconstituted Liposomes*

    Science.gov (United States)

    Sasahara, Ayako; Nanatani, Kei; Enomoto, Masaru; Kuwahara, Shigefumi; Abe, Keietsu

    2011-01-01

    The aspartate:alanine antiporter (AspT) of the lactic acid bacterium Tetragenococcus halophilus is a member of the aspartate:alanine exchanger (AAEx) transporter family. T. halophilus AspT catalyzes the electrogenic exchange of l-aspartate1− with l-alanine0. Although physiological functions of AspT were well studied, l-aspartate1−:l-alanine0 antiport mechanisms are still unsolved. Here we report that the binding sites of l-aspartate and l-alanine are independently present in AspT by means of the kinetic studies. We purified His6-tagged T. halophilus AspT and characterized its kinetic properties when reconstituted in liposomes (Km = 0.35 ± 0.03 mm for l-aspartate, Km = 0.098 ± 0 mm for d-aspartate, Km = 26 ± 2 mm for l-alanine, Km = 3.3 ± 0.2 mm for d-alanine). Competitive inhibition by various amino acids of l-aspartate or l-alanine in self-exchange reactions revealed that l-cysteine selectively inhibited l-aspartate self-exchange but only weakly inhibited l-alanine self-exchange. Additionally, l-serine selectively inhibited l-alanine self-exchange but barely inhibited l-aspartate self-exchange. The aspartate analogs l-cysteine sulfinic acid, l-cysteic acid, and d-cysteic acid competitively and strongly inhibited l-aspartate self-exchange compared with l-alanine self-exchange. Taken together, these kinetic data suggest that the putative binding sites of l-aspartate and l-alanine are independently located in the substrate translocation pathway of AspT. PMID:21719707

  10. L-Serine overproduction with minimization of by-product synthesis by engineered Corynebacterium glutamicum.

    Science.gov (United States)

    Zhu, Qinjian; Zhang, Xiaomei; Luo, Yuchang; Guo, Wen; Xu, Guoqiang; Shi, Jinsong; Xu, Zhenghong

    2015-02-01

    The direct fermentative production of L-serine by Corynebacterium glutamicum from sugars is attractive. However, superfluous by-product accumulation and low L-serine productivity limit its industrial production on large scale. This study aimed to investigate metabolic and bioprocess engineering strategies towards eliminating by-products as well as increasing L-serine productivity. Deletion of alaT and avtA encoding the transaminases and introduction of an attenuated mutant of acetohydroxyacid synthase (AHAS) increased both L-serine production level (26.23 g/L) and its productivity (0.27 g/L/h). Compared to the parent strain, the by-products L-alanine and L-valine accumulation in the resulting strain were reduced by 87 % (from 9.80 to 1.23 g/L) and 60 % (from 6.54 to 2.63 g/L), respectively. The modification decreased the metabolic flow towards the branched-chain amino acids (BCAAs) and induced to shift it towards L-serine production. Meanwhile, it was found that corn steep liquor (CSL) could stimulate cell growth and increase sucrose consumption rate as well as L-serine productivity. With addition of 2 g/L CSL, the resulting strain showed a significant improvement in the sucrose consumption rate (72 %) and the L-serine productivity (67 %). In fed-batch fermentation, 42.62 g/L of L-serine accumulation was achieved with a productivity of 0.44 g/L/h and yield of 0.21 g/g sucrose, which was the highest production of L-serine from sugars to date. The results demonstrated that combined metabolic and bioprocess engineering strategies could minimize by-product accumulation and improve L-serine productivity.

  11. 1H-NMR and HPLC studies of the changes involved in volume regulation in the muscle fibres of the crab, Hemigrapsus edwardsi.

    Science.gov (United States)

    Bedford, J J; Smith, R A; Thomas, M; Leader, J P

    1991-01-01

    1. The process of cell volume readjustment, during adaptation to salinity changes, in muscle fibres of the euryhaline New Zealand shore crab, Hemigrapsus edwardsi, involve large changes in the amounts of free amino acid. 2. These are taurine, proline, alanine, arginine, glutamic acid, glycine and serine. 3. These changes may be quantified by High Performance Liquid Chromatography, and qualitatively demonstrated by proton nuclear magnetic resonance spectroscopy.

  12. Differentiated human midbrain-derived neural progenitor cells express excitatory strychnine-sensitive glycine receptors containing α2β subunits.

    Directory of Open Access Journals (Sweden)

    Florian Wegner

    Full Text Available BACKGROUND: Human fetal midbrain-derived neural progenitor cells (NPCs may deliver a tissue source for drug screening and regenerative cell therapy to treat Parkinson's disease. While glutamate and GABA(A receptors play an important role in neurogenesis, the involvement of glycine receptors during human neurogenesis and dopaminergic differentiation as well as their molecular and functional characteristics in NPCs are largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we investigated NPCs in respect to their glycine receptor function and subunit expression using electrophysiology, calcium imaging, immunocytochemistry, and quantitative real-time PCR. Whole-cell recordings demonstrate the ability of NPCs to express functional strychnine-sensitive glycine receptors after differentiation for 3 weeks in vitro. Pharmacological and molecular analyses indicate a predominance of glycine receptor heteromers containing α2β subunits. Intracellular calcium measurements of differentiated NPCs suggest that glycine evokes depolarisations mediated by strychnine-sensitive glycine receptors and not by D-serine-sensitive excitatory glycine receptors. Culturing NPCs with additional glycine, the glycine-receptor antagonist strychnine, or the Na(+-K(+-Cl(- co-transporter 1 (NKCC1-inhibitor bumetanide did not significantly influence cell proliferation and differentiation in vitro. CONCLUSIONS/SIGNIFICANCE: These data indicate that NPCs derived from human fetal midbrain tissue acquire essential glycine receptor properties during neuronal maturation. However, glycine receptors seem to have a limited functional impact on neurogenesis and dopaminergic differentiation of NPCs in vitro.

  13. L-alanine uptake in membrane vesicles from Mytilus edulis gills

    International Nuclear Information System (INIS)

    Pajor, A.M.; Wright, S.H.

    1986-01-01

    Previous studies have shown that gills from M. edulis can accumulate L-alanine from seawater by a saturable process specific for α-neutral amino acids. This uptake occurs against chemical gradients in excess of 10 6 to 1. To further characterize this uptake, membrane vesicles were prepared from M. edulis gill tissue by differential centrifugation. Enrichments of putative enzyme markers (relative to that in combined initial fractions) were as follows: γ-Glutamyltranspeptidase, 25-30x; Alkaline Phosphatase, 5-6x; K + -dependent para-Nitrophenyl Phosphatase, 3-5x; Succinate Dehydrogenase 0.1-0.2x. These results suggest that the preparation is enriched in plasma membranes, although histochemical studies will be needed to verify this. The time course of 14 C-L-alanine uptake in the presence of inwardly-directed Na + gradient showed a transient overshoot (3-5 fold) at 10 minutes which decreased to equilibrium after six hours. The size of the overshoot and early uptake rates depended on the size of the inwardly-directed Na + gradient. No overshoot was seen in the presence of inwardly-directed gradients of LiCl or choline-Cl, or with equilibrium concentrations NaCl or mannitol. A reduced overshoot was seen with a gradient of NaSCN. A small overshoot was seen with an inwardly-directed gradient of KCl. Transport of L-alanine included saturable and diffusive components. Uptake of 6 μM L-alanine was inhibited more than 80% by 100 μM α-zwitterionic amino acids (alanine, leucine, glycine); by 30 to 75% by proline, aspartate and lysine; and less than 20% by a β-amino acid, taurine. The results of these experiments agree with those from intact gill studies and support the hypothesis that L-alanine is transported into gill epithelial cells by a secondary active transport process involving Na +

  14. Amino Acid Content of the Gamma Irradiated Cotton Leaf-Worm, Spodoptera Littoralis (Boisd.)

    International Nuclear Information System (INIS)

    Sobeiha, A.K.; Sallam, H.A.; El-Shall, S.S.A.

    2000-01-01

    The effects of gamma irradiation on amino acid content of the cotton leaf worm Spodoptera Littoralis was studied.The identified amino acids in the total body tissue of male moths were Theronine, Serine, Glutamic, Glycine, Alanine, Valine, Cystine, Methionine, Isoleucine, Leucine, Tyrosine, Phenylalanine, Lysine, Histidine and Arginine. The irradiation of full grown male pupae with doses 100,200 and 300 Gy decreased the total quantity of amino acids and the amount of most individual amino acids in male moths of P 1 or F 1 generations with some exceptions for Threonine, Alanine, Glycine, Serine, Valine, Cystine and Methionine which were increased.The effect of irradiation on amino acid content of the reproductive system tissues for each male or female were also studied.The results indicated that irradiation decreased the total quantity of amino acid content of both sexes by increasing the dose and males were more radiosensitive than females. Also, irradiation decreased the amount of individual amino acids in both sexes with certain exceptions, e.g. Alanine, Methionine and Tyrosine which increased in the reproductive system of male, and Methionine which increased by more than four times as control.The amino acid content was determined as well in F 1 egg progeny, which was produced from irradiated males Irradiation doses (100, 200 and 300 Gy) decreased the total quantity of amino acids, and all individual ones except Cystine.The greatest reduction (54.9% was observed with Lysine at 300 Gy as compared to control

  15. Simultaneous analysis of D-alanine, D-aspartic acid, and D-serine using chiral high-performance liquid chromatography-tandem mass spectrometry and its application to the rat plasma and tissues.

    Science.gov (United States)

    Karakawa, Sachise; Shimbo, Kazutaka; Yamada, Naoyuki; Mizukoshi, Toshimi; Miyano, Hiroshi; Mita, Masashi; Lindner, Wolfgang; Hamase, Kenji

    2015-11-10

    A highly sensitive and selective chiral LC-MS/MS method for D-alanine, D-aspartic acid and D-serine has been developed using the precolumn derivatization reagents, 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AccQ-Tag) or p-N,N,N-trimethylammonioanilyl N'-hydroxysuccinimidyl carbamate iodide (TAHS). The thus N-tagged enantiomers of the derivatized amino acids were nicely separated within 20min using the cinchona alkaloid-based zwittterionic ion-exchange type enantioselective column, Chiralpak ZWIX(+). The selected reaction monitoring was applied for detecting the target d-amino acids in biological matrices. By using the present chiral LC-MS/MS method, the three d-amino acids and their l-forms could be simultaneously determined in the range of 0.1-500nmol/mL. Finally, the technique was successfully applied to rat plasma and tissue samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Changes in the free amino acid composition with maturity of the noble cultivar of Vitis rotundifolia Michx. grape.

    Science.gov (United States)

    Lamikanra, O; Kassa, A K

    1999-12-01

    The changes in amino acid composition that occur with maturity of the Noble cultivar of the Vitis rotundifolia Michx. (muscadine) grape were determined by HPLC. Eighteen amino acids were identified. Histidine was the most prominent amino acid followed by alanine. The concentrations of most of the major amino acids (alanine, glycine, histidine, valine, isoleucine, aspartic acid, and serine) were highest at verasion. Glutamine and threonine contents dropped sharply after fruit set, while those of arginine and proline increased gradually with maturity and ripening. Tyrosine content increased gradually with maturity and ripening following a slight drop after fruit set. In ripe grapes, seeds contained most of the amino acids in mature grapes (50%) followed by the pulp (23%), the juice (15%), and the skin (11%). Alanine, histidine, and arginine were the principal amino acids identified in the juice. Alanine, histidine, arginine, valine, glutamine, aspartic acid, proline, serine, and threonine accounted for about 90% of the amino acids in the pulp. In seeds, alanine, proline, asparagine, and histidine accounted for over 55% of the amino acids, while alanine and histidine were found to be the predominant free amino acids in the skin. The profile indicates some differences in the changes in amino acid composition with berry maturity and relative amounts of amino acids present in muscadine compared to those in nonmuscadine grape species.

  17. Lack of Effect of Sodium Benzoate at Reported Clinical Therapeutic Concentration on d-Alanine Metabolism in Dogs.

    Science.gov (United States)

    Popiolek, Michael; Tierney, Brendan; Steyn, Stefanus J; DeVivo, Michael

    2018-06-19

    Cognitive decline and psychosis have been hypothesized to be mediated by N-methyl-d-aspartate receptor (NMDAR) hypofunction. Consistent with this hypothesis, chronic treatment with d-alanine, a coagonist at the glycine site of the NMDAR, leads to an improvement of positive and cognitive symptoms in schizophrenic patients. d-alanine is oxidized by d-amino acid oxidase (DAAO); thus, an inhibitor of DAAO would be expected to enhance d-alanine levels and likewise lead to desirable clinical outcomes. Sodium benzoate, on the basis of d-amino acid inhibition, was observed to display beneficial clinical effects in schizophrenic and Alzheimer's patients. However, in the clinical pilot studies using sodium benzoate, d-amino acids were not quantified to verify that sodium benzoate's efficacy was mediated through DAAO inhibition. In this study, d-alanine content was monitored in cerebral spinal fluid (CSF) of dogs treated with daily injections of d-alanine (30 mg/kg) alone and in combination with sodium benzoate (30 mg/kg) for seven consecutive days. We reasoned that the cerebral spinal fluid d-alanine quantity is reflective of the brain d-alanine levels and it would increase as a consequence of DAAO inhibition with sodium benzoate. We found that d-alanine treatment lead to maximal concentration of 7.51 μM CSF d-alanine level; however, coadministration of sodium benzoate and d-alanine did not change CSF d-alanine level beyond that of d-alanine treatment alone. As a consequence, we conclude that clinical efficacy associated with chronic administration of sodium benzoate in schizophrenic and Alzheimer's patients is likely not mediated through inhibition of DAAO.

  18. Catalytic Stereoinversion of L-Alanine to Deuterated D-Alanine.

    Science.gov (United States)

    Moozeh, Kimia; So, Soon Mog; Chin, Jik

    2015-08-03

    A combination of an achiral pyridoxal analogue and a chiral base has been developed for catalytic deuteration of L-alanine with inversion of stereochemistry to give deuterated D-alanine under mild conditions (neutral pD and 25 °C) without the use of any protecting groups. This system can also be used for catalytic deuteration of D-alanine with retention of stereochemistry to give deuterated D-alanine. Thus a racemic mixture of alanine can be catalytically deuterated to give an enantiomeric excess of deuterated D-alanine. While catalytic deracemization of alanine is forbidden by the second law of thermodynamics, this system can be used for catalytic deracemization of alanine with deuteration. Such green and biomimetic approach to catalytic stereocontrol provides insights into efficient amino acid transformations. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. ATM-mediated Snail Serine 100 phosphorylation regulates cellular radiosensitivity

    International Nuclear Information System (INIS)

    Boohaker, Rebecca J.; Cui, Xiaoli; Stackhouse, Murray; Xu, Bo

    2013-01-01

    Purpose: Activation of the DNA damage responsive protein kinase ATM is a critical step for cellular survival in response to ionizing irradiation (IR). Direct targets of ATM regulating radiosensitivity remain to be fully investigated. We have recently reported that ATM phosphorylates the transcriptional repressor Snail on Serine 100. We aimed to further study the functional significance of ATM-mediated Snail phosphorylation in response to IR. Material and methods: We transfected vector-only, wild-type, the Serine 100 to alanine (S100A) or to glutamic acid (S100E) substitution of Snail into various cell lines. We assessed colony formation, γ-H2AX focus formation and the invasion index in the cells treated with or without IR. Results: We found that over-expression of the S100A mutant Snail in HeLa cells significantly increased radiosensitivity. Meanwhile the expression of S100E, a phospho-mimicking mutation, resulted in enhanced radio-resistance. Interestingly, S100E could rescue the radiosensitive phenotype in ATM-deficient cells. We also found that expression of S100E increased γ-H2AX focus formation and compromised inhibition of invasion in response to IR independent of cell survival. Conclusion: ATM-mediated Snail Serine 100 phosphorylation in response to IR plays an important part in the regulation of radiosensitivity

  20. Investigating the effect of a single glycine to alanine substitution on interactions of antimicrobial peptide latarcin 2a with a lipid membrane.

    Science.gov (United States)

    Idiong, Grace; Won, Amy; Ruscito, Annamaria; Leung, Bonnie O; Hitchcock, Adam P; Ianoul, Anatoli

    2011-09-01

    Latarcins are linear, α-helical antimicrobial peptides purified from the venom of the Central Asian spider Lachesana tarabaevi, with lytic activity against Gram-positive and Gram-negative bacteria, erythrocytes, and yeast at micromolar concentrations. In this work, we investigated the role of the hinge in latarcin 2a (ltc2a, GLFGKLIKKFGRKAISYAVKKARGKH-COOH), which adopts a helix-hinge-helix conformation in membrane-mimicking environments, on peptide-membrane interactions and its potential effect on the selective toxicity of the peptide. A modified latarcin 2a, ltc2aG11A, obtained by replacing the glycine at position 11 with alanine (ltc2aG11A, GLFGKLIKKFARKAISYAVKKARGKH-COOH), adopts a more rigid structure due to the reduced conformational flexibility. Langmuir monolayer measurements combined with atomic force microscopy and X-ray photoemission electron microscopy (X-PEEM) indicate that both peptides bind and insert preferentially into anionic compared with zwitterionic phospholipid monolayers. Modified ltc2aG11A was found to be more disruptive of supported phospholipid bilayer modeling mammalian cell membrane. However, no considerable difference in lytic activity of the two peptides toward bacterial membrane was found. Overall the data indicate that decrease in the flexibility of ltc2a induced by the modification in the hinge region is likely to increase the peptide's nonspecific interactions with zwitterionic cell membranes and potentially increase its toxicity against eukaryotic cells.

  1. Free amino acid content and metabolic activities of setting and aborting soybean ovaries

    International Nuclear Information System (INIS)

    Ghiasi, H.; Paech, C.; Dybing, C.D.

    1987-01-01

    Fruits of soybean (glycine max [L.] Merr.) that are destined to abscise shortly after anthesis grow more slowly than fruits that will be retained. In this work, amino acid composition, protein metabolism, and nucleic acid metabolism were studied in setting and abscising soybean ovaries from anthesis to 6 days after anthesis. Principal free amino acids were asparagine, aspartic acid, glutamic acid, serine, and glutamine. Percent aspartate and glutamate declined as the ovaries grew, with aspartate declining more in abscising and glutamate more in setting ovaries. Percent glutamate was positively correlated to percent abscission throughout the period. Proline, serine, and leucine were positively correlated to abscission from 0 to 2 days after anthesis, whereas significant negative correlations were observed at these ages for ethanolamine and arginine. 75 Se fed as selenate and 14 C fed as sucrose, glycine, and alanine were readily incorporated into soluble and insoluble proteins in a 24-hour in vitro incubation. Radioactivity of total proteins, expressed on a per-ovary basis, was negatively correlated with percent abscission and positively correlated with ovary weight. [ 14 C]Glutamine and serine followed the opposite pattern, with greater protein labeling in abscising than in setting ovaries. When data were expressed as disintegrations per minute per milligram ovary fresh weight, protein labeling from alanine was seen to be significantly greater in abscising ovaries at anthesis and throughout the sampling period. Nucleic acid labeling from uridine was highly correlated to ovary weight; labeling from thymidine was greater in setting than abscising ovaries at anthesis and in abscising ovaries at later stages of development

  2. Characterization of the Usage of the Serine Metabolic Network in Human Cancer

    Directory of Open Access Journals (Sweden)

    Mahya Mehrmohamadi

    2014-11-01

    Full Text Available The serine, glycine, one-carbon (SGOC metabolic network is implicated in cancer pathogenesis, but its general functions are unknown. We carried out a computational reconstruction of the SGOC network and then characterized its expression across thousands of cancer tissues. Pathways including methylation and redox metabolism exhibited heterogeneous expression indicating a strong context dependency of their usage in tumors. From an analysis of coexpression, simultaneous up- or downregulation of nucleotide synthesis, NADPH, and glutathione synthesis was found to be a common occurrence in all cancers. Finally, we developed a method to trace the metabolic fate of serine using stable isotopes, high-resolution mass spectrometry, and a mathematical model. Although the expression of single genes didn’t appear indicative of flux, the collective expression of several genes in a given pathway allowed for successful flux prediction. Altogether, these findings identify expansive and heterogeneous functions for the SGOC metabolic network in human cancer.

  3. The conserved glycine residues in the transmembrane domain of the Semliki Forest virus fusion protein are not required for assembly and fusion

    International Nuclear Information System (INIS)

    Liao Maofu; Kielian, Margaret

    2005-01-01

    The alphavirus Semliki Forest virus (SFV) infects cells via a low pH-triggered fusion reaction mediated by the viral E1 protein. Both the E1 fusion peptide and transmembrane (TM) domain are essential for membrane fusion, but the functional requirements for the TM domain are poorly understood. Here we explored the role of the five TM domain glycine residues, including the highly conserved glycine pair at E1 residues 415/416. SFV mutants with alanine substitutions for individual or all five glycine residues (5G/A) showed growth kinetics and fusion pH dependence similar to those of wild-type SFV. Mutants with increasing substitution of glycine residues showed an increasingly more stringent requirement for cholesterol during fusion. The 5G/A mutant showed decreased fusion kinetics and extent in fluorescent lipid mixing assays. TM domain glycine residues thus are not required for efficient SFV fusion or assembly but can cause subtle effects on the properties of membrane fusion

  4. The Amino Acid Composition of the Sutter's Mill Carbonaceous Chondrite

    Science.gov (United States)

    Glavin, D. P.; Burton, A. S.; Elsila, J. E.; Dworkin, J. P.; Yin, Q. Z.; Cooper, G.; Jenniskens, P.

    2012-01-01

    In contrast to the Murchison meteorite which had a complex distribution of amino acids with a total C2 to Cs amino acid abundance of approx.14,000 parts-per-billion (ppb) [2], the Sutters Mill meteorite was found to be highly depleted in amino acids. Much lower abundances (approx.30 to 180 ppb) of glycine, beta-alanine, L-alanine and L-serine were detected in SM2 above procedural blank levels indicating that this meteorite sample experienced only minimal terrestrial amino acid contamination after its fall to Earth. Carbon isotope measurements will be necessary to establish the origin of glycine and beta-alanine in SM2. Other non-protein amino acids that are rare on Earth, yet commonly found in other CM meteorites such as aaminoisobutyric acid (alpha-AIB) and isovaline, were not identified in SM2. However, traces of beta-AIB (approx.1 ppb) were detected in SM2 and could be" extraterrestrial in origin. The low abundances of amino acids in the Sutter's Mill meteorite is consistent with mineralogical evidence that at least some parts of the Sutter's Mill meteorite parent body experienced extensive aqueous and/or thermal alteration.

  5. Carbon allocation to major metabolites in illuminated leaves is not just proportional to photosynthesis when gaseous conditions (CO2 and O2 ) vary.

    Science.gov (United States)

    Abadie, Cyril; Bathellier, Camille; Tcherkez, Guillaume

    2018-04-01

    In gas-exchange experiments, manipulating CO 2 and O 2 is commonly used to change the balance between carboxylation and oxygenation. Downstream metabolism (utilization of photosynthetic and photorespiratory products) may also be affected by gaseous conditions but this is not well documented. Here, we took advantage of sunflower as a model species, which accumulates chlorogenate in addition to sugars and amino acids (glutamate, alanine, glycine and serine). We performed isotopic labelling with 13 CO 2 under different CO 2 /O 2 conditions, and determined 13 C contents to compute 13 C-allocation patterns and build-up rates. The 13 C content in major metabolites was not found to be a constant proportion of net fixed carbon but, rather, changed dramatically with CO 2 and O 2 . Alanine typically accumulated at low O 2 (hypoxic response) while photorespiratory intermediates accumulated under ambient conditions and at high photorespiration, glycerate accumulation exceeding serine and glycine build-up. Chlorogenate synthesis was relatively more important under normal conditions and at high CO 2 and its synthesis was driven by phosphoenolpyruvate de novo synthesis. These findings demonstrate that carbon allocation to metabolites other than photosynthetic end products is affected by gaseous conditions and therefore the photosynthetic yield of net nitrogen assimilation varies, being minimal at high CO 2 and maximal at high O 2 . © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

  6. Conserved water molecules in bacterial serine hydroxymethyltransferases.

    Science.gov (United States)

    Milano, Teresa; Di Salvo, Martino Luigi; Angelaccio, Sebastiana; Pascarella, Stefano

    2015-10-01

    Water molecules occurring in the interior of protein structures often are endowed with key structural and functional roles. We report the results of a systematic analysis of conserved water molecules in bacterial serine hydroxymethyltransferases (SHMTs). SHMTs are an important group of pyridoxal-5'-phosphate-dependent enzymes that catalyze the reversible conversion of l-serine and tetrahydropteroylglutamate to glycine and 5,10-methylenetetrahydropteroylglutamate. The approach utilized in this study relies on two programs, ProACT2 and WatCH. The first software is able to categorize water molecules in a protein crystallographic structure as buried, positioned in clefts or at the surface. The other program finds, in a set of superposed homologous proteins, water molecules that occur approximately in equivalent position in each of the considered structures. These groups of molecules are referred to as 'clusters' and represent structurally conserved water molecules. Several conserved clusters of buried or cleft water molecules were found in the set of 11 bacterial SHMTs we took into account for this work. The majority of these clusters were not described previously. Possible structural and functional roles for the conserved water molecules are envisaged. This work provides a map of the conserved water molecules helpful for deciphering SHMT mechanism and for rational design of molecular engineering experiments. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. Monopeptide versus Monopeptoid: Insights on Structure and Hydration of Aqueous Alanine and Sarcosine via X-ray Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Uejio, Janel S.; Schwartz, Craig P.; Duffin, Andrew M.; England, Alice; Prendergast, David; Saykally, Richard J.

    2009-11-19

    Despite the obvious significance, the aqueous interactions of peptides remain incompletely understood. Their synthetic analogues called peptoids (poly-N-substituted glycines), have recently emerged as a promising biomimetic material, particularly due to their robust secondary structure and resistance to denaturation. We describe comparative near-edge x-ray absorption fine structure (NEXAFS) spectroscopy studies of aqueous sarcosine, the simplest peptoid, and alanine, its peptide isomer, interpreted by density functional theory calculations. The sarcosine nitrogen K-edge spectrum is blue-shifted with respect to that of alanine, in agreement with our calculations; we conclude that this shift results primarily from the methyl group substitution on the nitrogen of sarcosine. Our calculations indicate that the nitrogen K-edge spectrum of alanine differs significantly between dehydrated and hydrated scenarios, while that of the sarcosine zwitterion is less affected by hydration. In contrast, the computed sarcosine spectrum is greatly impacted by conformational variations, while the alanine spectrum is not. This relates to a predicted solvent dependence for alanine, as compared to sarcosine. Additionally, we show the theoretical nitrogen K-edge spectra to be sensitive to the degree of hydration, indicating that experimental X-ray spectroscopy may be able to distinguish between bulk and partial hydration, such as found in confined environments near proteins and in reverse micelles.

  8. Phosphorylation of SAF-A/hnRNP-U Serine 59 by Polo-Like Kinase 1 Is Required for Mitosis.

    Science.gov (United States)

    Douglas, Pauline; Ye, Ruiqiong; Morrice, Nicholas; Britton, Sébastien; Trinkle-Mulcahy, Laura; Lees-Miller, Susan P

    2015-08-01

    Scaffold attachment factor A (SAF-A), also called heterogenous nuclear ribonuclear protein U (hnRNP-U), is phosphorylated on serine 59 by the DNA-dependent protein kinase (DNA-PK) in response to DNA damage. Since SAF-A, DNA-PK catalytic subunit (DNA-PKcs), and protein phosphatase 6 (PP6), which interacts with DNA-PKcs, have all been shown to have roles in mitosis, we asked whether DNA-PKcs phosphorylates SAF-A in mitosis. We show that SAF-A is phosphorylated on serine 59 in mitosis, that phosphorylation requires polo-like kinase 1 (PLK1) rather than DNA-PKcs, that SAF-A interacts with PLK1 in nocodazole-treated cells, and that serine 59 is dephosphorylated by protein phosphatase 2A (PP2A) in mitosis. Moreover, cells expressing SAF-A in which serine 59 is mutated to alanine have multiple characteristics of aberrant mitoses, including misaligned chromosomes, lagging chromosomes, polylobed nuclei, and delayed passage through mitosis. Our findings identify serine 59 of SAF-A as a new target of both PLK1 and PP2A in mitosis and reveal that both phosphorylation and dephosphorylation of SAF-A serine 59 by PLK1 and PP2A, respectively, are required for accurate and timely exit from mitosis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Glycine Increases Insulin Sensitivity and Glutathione Biosynthesis and Protects against Oxidative Stress in a Model of Sucrose-Induced Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Mohammed El-Hafidi

    2018-01-01

    Full Text Available Oxidative stress and redox status play a central role in the link between insulin resistance (IR and lipotoxicity in metabolic syndrome. This mechanistic link may involve alterations in the glutathione redox state. We examined the effect of glycine supplementation to diet on glutathione biosynthesis, oxidative stress, IR, and insulin cell signaling in liver from sucrose-fed (SF rats characterized by IR and oxidative stress. Our hypothesis is that the correction of glutathione levels by glycine treatment leads to reduced oxidative stress, a mechanism associated with improved insulin signaling and IR. Glycine treatment decreases the levels of oxidative stress markers in liver from SF rats and increases the concentrations of glutathione (GSH and γ-glutamylcysteine and the amount of γ-glutamylcysteine synthetase (γ-GCS, a key enzyme of GSH biosynthesis in liver from SF rats. In liver from SF rats, glycine also decreases the insulin-induced phosphorylation of insulin receptor substrate-1 (ISR-1 in serine residue and increases the phosphorylation of insulin receptor β-subunit (IR-β in tyrosine residue. Thus, supplementing diets with glycine to correct GSH deficiency and to reduce oxidative stress provides significant metabolic benefits to SF rats by improving insulin sensitivity.

  10. Influence of the composition of aqueous dimethylsulfoxide solvent on thermodynamics of complexing between 18-crown-6-ether and D,L-alanine

    Science.gov (United States)

    Usacheva, T. R.; Kuzmina, I. A.; Sharnin, V. A.; Chernov, I. V.; Matteoli, E.

    2012-07-01

    Standard thermodynamic parameters (log K o, Δr H o, TΔr S o) of complexing 18-crown-6 ether (18C6) with D,L-alanine (Ala) in mixed water-dimethysulfoxide (H2O-DMSO) solvents are calculated on the basis of calorimetric titration results. A rise in the DMSO concentration in mixed solvent is found to increase stability and increase the exothermicity of the formation of [Ala-18C6] molecular complex. Changes in the reaction energetic are shown to be determined by changes in the solvation state of 18C6 that is the characteristic of the reactions of molecular complex formation between 18C6 and D,L-alanine or glycine in water-organic solvents.

  11. Histone H3 Serine 28 Is Essential for Efficient Polycomb-Mediated Gene Repression in Drosophila

    Directory of Open Access Journals (Sweden)

    Philip Yuk Kwong Yung

    2015-06-01

    Full Text Available Trimethylation at histone H3K27 is central to the polycomb repression system. Juxtaposed to H3K27 is a widely conserved phosphorylatable serine residue (H3S28 whose function is unclear. To assess the importance of H3S28, we generated a Drosophila H3 histone mutant with a serine-to-alanine mutation at position 28. H3S28A mutant cells lack H3S28ph on mitotic chromosomes but support normal mitosis. Strikingly, all methylation states of H3K27 drop in H3S28A cells, leading to Hox gene derepression and to homeotic transformations in adult tissues. These defects are not caused by active H3K27 demethylation nor by the loss of H3S28ph. Biochemical assays show that H3S28A nucleosomes are a suboptimal substrate for PRC2, suggesting that the unphosphorylated state of serine 28 is important for assisting in the function of polycomb complexes. Collectively, our data indicate that the conserved H3S28 residue in metazoans has a role in supporting PRC2 catalysis.

  12. Phosphorylation of mouse serine racemase regulates D-serine synthesis

    DEFF Research Database (Denmark)

    Foltyn, Veronika N; Zehl, Martin; Dikopoltsev, Elena

    2010-01-01

    Serine racemase (SR) catalyses the synthesis of the transmitter/neuromodulator D-serine, which plays a major role in synaptic plasticity and N-methyl D-aspartate receptor neurotoxicity. We now report that SR is phosphorylated at Thr71 and Thr227 as revealed by mass spectrometric analysis and in v...... with a phosphorylation-deficient SR mutant indicate that Thr71 phosphorylation increases SR activity, suggesting a novel mechanism for regulating D-serine production....

  13. Mechanisms of glycine release, which build up synaptic and extrasynaptic glycine levels: the role of synaptic and non-synaptic glycine transporters.

    Science.gov (United States)

    Harsing, Laszlo G; Matyus, Peter

    2013-04-01

    Glycine is an amino acid neurotransmitter that is involved in both inhibitory and excitatory neurochemical transmission in the central nervous system. The role of glycine in excitatory neurotransmission is related to its coagonist action at glutamatergic N-methyl-D-aspartate receptors. The glycine levels in the synaptic cleft rise many times higher during synaptic activation assuring that glycine spills over into the extrasynaptic space. Another possible origin of extrasynaptic glycine is the efflux of glycine occurring from astrocytes associated with glutamatergic synapses. The release of glycine from neuronal or glial origins exhibits several differences compared to that of biogenic amines or other amino acid neurotransmitters. These differences appear in an external Ca(2+)- and temperature-dependent manner, conferring unique characteristics on glycine as a neurotransmitter. Glycine transporter type-1 at synapses may exhibit neural and glial forms and plays a role in controlling synaptic glycine levels and the spill over rate of glycine from the synaptic cleft into the extrasynaptic biophase. Non-synaptic glycine transporter type-1 regulates extrasynaptic glycine concentrations, either increasing or decreasing them depending on the reverse or normal mode operation of the carrier molecule. While we can, at best, only estimate synaptic glycine levels at rest and during synaptic activation, glycine concentrations are readily measurable via brain microdialysis technique applied in the extrasynaptic space. The non-synaptic N-methyl-D-aspartate receptor may obtain glycine for activation following its spill over from highly active synapses or from its release mediated by the reverse operation of non-synaptic glycine transporter-1. The sensitivity of non-synaptic N-methyl-D-aspartate receptors to glutamate and glycine is many times higher than that of synaptic N-methyl-D-aspartate receptors making the former type of receptor the primary target for drug action. Synaptic

  14. Amino acid catabolism and generation of volatiles by lactic acid bacteria.

    Science.gov (United States)

    Tavaria, F K; Dahl, S; Carballo, F J; Malcata, F X

    2002-10-01

    Twelve isolates of lactic acid bacteria, belonging to the Lactobacillus, Lactococcus, Leuconostoc, and Enterococcus genera, were previously isolated from 180-d-old Serra da Estrela cheese, a traditional Portuguese cheese manufactured from raw milk and coagulated with a plant rennet. These isolates were subsequently tested for their ability to catabolize free amino acids, when incubated independently with each amino acid in free form or with a mixture thereof. Attempts were made in both situations to correlate the rates of free amino acid uptake with the numbers of viable cells. When incubated individually, leucine, valine, glycine, aspartic acid, serine, threonine, lysine, glutamic acid, and alanine were degraded by all strains considered; arginine tended to build up, probably because of transamination of other amino acids. When incubated together, the degradation of free amino acids by each strain was dependent on pH (with an optimum pH around 6.0). The volatiles detected in ripened Serra da Estrela cheese originated mainly from leucine, phenylalanine, alanine, and valine, whereas in vitro they originated mainly from valine, phenylalanine, serine, leucine, alanine, and threonine. The wild strains tested offer a great potential for flavor generation, which might justify their inclusion in a tentative starter/nonstarter culture for that and similar cheeses.

  15. Investigation of the adsorption of amino acids on Pd(1 1 1): A density functional theory study

    International Nuclear Information System (INIS)

    James, Joanna N.; Han, Jeong Woo; Sholl, David S.

    2014-01-01

    Graphical abstract: - Highlights: • Density functional theory calculations have been performed to study the adsorption of glycine, alanine, norvaline, valine, proline, cysteine, and serine on Pd(1 1 1). • The common structural framework for the adsorption of most amino acids onto Pd(1 1 1) is in a tridentate fashion via a nitrogen atom and two oxygen atoms. • The shifts in vibrational frequencies associated with NHH and COO support the adsorption patterns of amino acids we examined. • The adsorption strength of amino acids depends on how much the molecules deform during the adsorption process. - Abstract: Density functional theory calculations have been used to study the adsorption of glycine, alanine, norvaline, valine, proline, cysteine, and serine on Pd(1 1 1). Most amino acids except cysteine adsorb onto the surface in a tridentate fashion through a nitrogen atom and both oxygen atoms. For cysteine, an additional bond is formed with the surface due to the strong affinity of the sulfur atom, resulting in a significantly larger adsorption energy. The adsorption patterns of amino acids we examined are supported by the shifts in vibrational frequencies associated with NHH and COO. The adsorption strength of amino acids depends on how much the molecules deform during the adsorption process. Understanding the adsorption of amino acids on Pd(1 1 1) provides fundamental information for future consideration of the interactions between their derivatives or more complicated biomolecules and metal surfaces

  16. Alanine water complexes.

    Science.gov (United States)

    Vaquero, Vanesa; Sanz, M Eugenia; Peña, Isabel; Mata, Santiago; Cabezas, Carlos; López, Juan C; Alonso, José L

    2014-04-10

    Two complexes of alanine with water, alanine-(H2O)n (n = 1,2), have been generated by laser ablation of the amino acid in a supersonic jet containing water vapor and characterized using Fourier transform microwave spectroscopy. In the observed complexes, water molecules bind to the carboxylic group of alanine acting as both proton donors and acceptors. In alanine-H2O, the water molecule establishes two intermolecular hydrogen bonds forming a six-membered cycle, while in alanine-(H2O)2 the two water molecules establish three hydrogen bonds forming an eight-membered ring. In both complexes, the amino acid moiety is in its neutral form and shows the conformation observed to be the most stable for the bare molecule. The microsolvation study of alanine-(H2O)n (n = 1,2) can be taken as a first step toward understanding bulk properties at a microscopic level.

  17. Phosphomimetic mutation of the mitotically phosphorylated serine 1880 compromises the interaction of the transmembrane nucleoporin gp210 with the nuclear pore complex

    International Nuclear Information System (INIS)

    Onischenko, Evgeny A.; Crafoord, Ellinor; Hallberg, Einar

    2007-01-01

    The nuclear pore complexes (NPCs) reversibly disassemble and reassemble during mitosis. Disassembly of the NPC is accompanied by phosphorylation of many nucleoporins although the function of this is not clear. It was previously shown that in the transmembrane nucleoporin gp210 a single serine residue at position 1880 is specifically phosphorylated during mitosis. Using amino acid substitution combined with live cell imaging, time-lapse microscopy and FRAP, we investigated the role of serine 1880 in binding of gp210 to the NPC in vivo. An alanine substitution mutant (S1880A) was significantly more dynamic at the NPC compared to the wild-type protein, suggesting that serine 1880 is important for binding of gp210 to the NPC. Moreover a glutamate substitution (S1880E) closely mimicking phosphorylated serine specifically interfered with incorporation of gp210 into the NPC and compromised its post-mitotic recruitment to the nuclear envelope of daughter nuclei. Our findings are consistent with the idea that mitotic phosphorylation acts to dissociate gp210 from the structural elements of the NPC

  18. Dose response of alanine and methyl alanine towards gamma and in-situ alpha irradiation

    International Nuclear Information System (INIS)

    Mohapatra, M.; Rajeswari, B.; Bhide, M.K.; Rane, Vinayak; Kadam, R.M.

    2017-01-01

    In situ alpha and external gamma dose response of two ESR (electron spin resonance) dosimetric materials namely alanine and methyl alanine were investigated. It was observed that alanine dosimeter had a better dose response in comparison to methyl alanine for the in-situ alpha irradiation by using 239 Pu powder. On the other hand, in case of gamma radiation, methyl alanine was found to have the sensitivity as twice that of alanine. (author)

  19. Persistent GABAA/C responses to gabazine, taurine and beta-alanine in rat hypoglossal motoneurons.

    Science.gov (United States)

    Chesnoy-Marchais, D

    2016-08-25

    In hypoglossal motoneurons, a sustained anionic current, sensitive to a blocker of ρ-containing GABA receptors, (1,2,5,6-tetrahydropyridin-4-yl)methylphosphinic acid (TPMPA) and insensitive to bicuculline, was previously shown to be activated by gabazine. In order to better characterize the receptors involved, the sensitivity of this atypical response to pentobarbital (30μM), allopregnanolone (0.3μM) and midazolam (0.5μM) was first investigated. Pentobarbital potentiated the response, whereas the steroid and the benzodiazepine were ineffective. The results indicate the involvement of hybrid heteromeric receptors, including at least a GABA receptor ρ subunit and a γ subunit, accounting for the pentobarbital-sensitivity. The effects of the endogenous β amino acids, taurine and β-alanine, which are released under various pathological conditions and show neuroprotective properties, were then studied. In the presence of the glycine receptor blocker strychnine (1μM), both taurine (0.3-1mM) and β-alanine (0.3mM) activated sustained anionic currents, which were partly blocked by TPMPA (100μM). Thus, both β amino acids activated ρ-containing GABA receptors in hypoglossal motoneurons. Bicuculline (20μM) reduced responses to taurine and β-alanine, but small sustained responses persisted in the presence of both strychnine and bicuculline. Responses to β-alanine were slightly increased by allopregnanolone, indicating a contribution of the bicuculline- and neurosteroid-sensitive GABAA receptors underlying tonic inhibition in these motoneurons. Since sustained activation of anionic channels inhibits most mature principal neurons, the ρ-containing GABA receptors permanently activated by taurine and β-alanine might contribute to some of their neuroprotective properties under damaging overexcitatory situations. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  20. Regulation of the Incorporation of Tissue Factor into Microparticles by Serine Phosphorylation of the Cytoplasmic Domain of Tissue Factor*

    Science.gov (United States)

    Collier, Mary E. W.; Ettelaie, Camille

    2011-01-01

    The mechanisms that regulate the incorporation and release of tissue factors (TFs) into cell-derived microparticles are as yet unidentified. In this study, we have explored the regulation of TF release into microparticles by the phosphorylation of serine residues within the cytoplasmic domain of TF. Wild-type and mutant forms of TF, containing alanine and aspartate substitutions at Ser253 and Ser258, were overexpressed in coronary artery and dermal microvascular endothelial cells and microparticle release stimulated with PAR2 agonist peptide (PAR2-AP). The release of TF antigen and activity was then monitored. In addition, the phosphorylation state of the two serine residues within the released microparticles and the cells was monitored for 150 min. The release of wild-type TF as procoagulant microparticles peaked at 90 min and declined thereafter in both cell types. The TF within these microparticles was phosphorylated at Ser253 but not at Ser258. Aspartate substitution of Ser253 resulted in rapid release of TF antigen but not activity, whereas TF release was reduced and delayed by alanine substitution of Ser253 or aspartate substitution of Ser258. Alanine substitution of Ser258 prolonged the release of TF following PAR2-AP activation. The release of TF was concurrent with phosphorylation of Ser253 and was followed by dephosphorylation at 120 min and phosphorylation of Ser258. We propose a sequential mechanism in which the phosphorylation of Ser253 through PAR2 activation results in the incorporation of TF into microparticles, simultaneously inducing Ser258 phosphorylation. Phosphorylation of Ser258 in turn promotes the dephosphorylation of Ser253 and suppresses the release of TF. PMID:21310953

  1. Aboveground feeding by soybean aphid, Aphis glycines, affects soybean cyst nematode, Heterodera glycines, reproduction belowground.

    Directory of Open Access Journals (Sweden)

    Michael T McCarville

    Full Text Available Heterodera glycines is a cyst nematode that causes significant lost soybean yield in the U.S. Recent studies observed the aphid Aphis glycines and H. glycines interacting via their shared host, soybean, Glycine max. A greenhouse experiment was conducted to discern the effect of A. glycines feeding on H. glycines reproduction. An H. glycines-susceptible cultivar, Kenwood 94, and a resistant cultivar, Dekalb 27-52, were grown in H. glycines-infested soil for 30 and 60 d. Ten days after planting, plants were infested with either zero, five, or ten aphids. At 30 and 60 d, the number of H. glycines females and cysts (dead females and the number of eggs within were counted. In general, H. glycines were less abundant on the resistant than the susceptible cultivar, and H. glycines abundance increased from 30 to 60 d. At 30 d, 33% more H. glycines females and eggs were produced on the resistant cultivar in the ten-aphid treatment compared to the zero-aphid treatment. However, at 30 d the susceptible cultivar had 50% fewer H. glycines females and eggs when infested with ten aphids. At 60 d, numbers of H. glycines females and cysts and numbers of eggs on the resistant cultivar were unaffected by A. glycines feeding, while numbers of both were decreased by A. glycines on the susceptible cultivar. These results indicate that A. glycines feeding improves the quality of soybean as a host for H. glycines, but at higher herbivore population densities, this effect is offset by a decrease in resource quantity.

  2. Pre-synaptic glycine GlyT1 transporter--NMDA receptor interaction: relevance to NMDA autoreceptor activation in the presence of Mg2+ ions.

    Science.gov (United States)

    Musante, Veronica; Summa, Maria; Cunha, Rodrigo A; Raiteri, Maurizio; Pittaluga, Anna

    2011-05-01

    Rat hippocampal glutamatergic terminals possess NMDA autoreceptors whose activation by low micromolar NMDA elicits glutamate exocytosis in the presence of physiological Mg(2+) (1.2 mM), the release of glutamate being significantly reduced when compared to that in Mg(2+)-free condition. Both glutamate and glycine were required to evoke glutamate exocytosis in 1.2 mM Mg(2+), while dizocilpine, cis-4-[phosphomethyl]-piperidine-2-carboxylic acid and 7-Cl-kynurenic acid prevented it, indicating that occupation of both agonist sites is needed for receptor activation. D-serine mimicked glycine but also inhibited the NMDA/glycine-induced release of [(3H]D-aspartate, thus behaving as a partial agonist. The NMDA/glycine-induced release in 1.2 mM Mg(2+) strictly depended on glycine uptake through the glycine transporter type 1 (GlyT1), because the GlyT1 blocker N-[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)propyl])sarcosine hydrochloride, but not the GlyT2 blocker Org 25534, prevented it. Accordingly, [(3)H]glycine was taken up during superfusion, while lowering the external concentration of Na(+), the monovalent cation co-transported with glycine by GlyT1, abrogated the NMDA-induced effect. Western blot analysis of subsynaptic fractions confirms that GlyT1 and NMDA autoreceptors co-localize at the pre-synaptic level, where GluN3A subunits immunoreactivity was also recovered. It is proposed that GlyT1s coexist with NMDA autoreceptors on rat hippocampal glutamatergic terminals and that glycine taken up by GlyT1 may permit physiological activation of NMDA pre-synaptic autoreceptors. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

  3. Alanine dosimetry for clinical applications. Proceedings

    International Nuclear Information System (INIS)

    Anton, M.

    2006-05-01

    The following topics are dealt with: Therapy level alanine dosimetry at the UK Nationational Physical Laboratory, alanine as a precision validation tool for reference dosimetry, composition of alanine pellet dosimeters, the angular dependence of the alanine ESR spectrum, the CIAE alanine dosimeter for radiotherapy level, a correction for temporal evolution effects in alanine dosimetry, next-generation services foe e-traceability to ionization radiation national standards, establishing e-traceability to HIST high-dose measurement standards, alanine dosimetry of dose delivery from clinical accelerators, the e-scan alanine dosimeter reader, alanine dosimetry at ISS, verification of the integral delivered dose for IMRT treatment in the head and neck region with ESR/alanine dosimetry, alanine dosimetry in helical tomotherapy beams, ESR dosimetry research and development at the University of Palermo, lithium formate as a low-dose EPR radiation dosimeter, sensitivity enhancement of alanine/EPR dosimetry. (HSI)

  4. Oral administration of D-alanine in monkeys robustly increases plasma and cerebrospinal fluid levels but experimental D-amino acid oxidase inhibitors had minimal effect.

    Science.gov (United States)

    Rojas, Camilo; Alt, Jesse; Ator, Nancy A; Wilmoth, Heather; Rais, Rana; Hin, Niyada; DeVivo, Michael; Popiolek, Michael; Tsukamoto, Takashi; Slusher, Barbara S

    2016-09-01

    Hypofunction of the N-methyl-d-aspartate (NMDA) receptor is thought to exacerbate psychosis in patients diagnosed with schizophrenia. Consistent with this hypothesis, D-alanine, a co-agonist at the glycine site of the NMDA receptor, was shown to improve positive and cognitive symptoms when used as add-on therapy for schizophrenia treatment. However, D-alanine had to be administered at high doses (~7 g) to observe clinical effects. One possible reason for the high dose is that D-alanine could be undergoing oxidation by D-amino acid oxidase (DAAO) before it reaches the brain. If this is the case, the dose could be reduced by co-administration of D-alanine with a DAAO inhibitor (DAAOi). Early studies with rodents showed that co-administration of D-alanine with 5-chloro-benzo[d]isoxazol-3-ol (CBIO), a prototype DAAOi, significantly enhanced the levels of extracellular D-alanine in the frontal cortex compared with D-alanine alone. Further, the use of CBIO reduced the dose of D-alanine needed to attenuate prepulse inhibition deficits induced by dizocilpine. The objective of the work reported herein was to confirm the hypothesis that DAAO inhibition can enhance D-alanine exposure in a species closer to humans: non-human primates. We report that while oral D-alanine administration to baboons (10 mg/kg) enhanced D-alanine plasma and CSF levels over 20-fold versus endogenous levels, addition of experimental DAAOi to the regimen exhibited a 2.2-fold enhancement in plasma and no measurable effect on CSF levels. The results provide caution regarding the utility of DAAO inhibition to increase D-amino acid levels as treatment for patients with schizophrenia. © The Author(s) 2016.

  5. beta-Chloro-L-alanine inhibition of the Escherichia coli alanine-valine transaminase.

    OpenAIRE

    Whalen, W A; Wang, M D; Berg, C M

    1985-01-01

    beta-Chloro-L-alanine, an amino acid analog which inhibits a number of enzymes, reversibly inhibited the Escherichia coli K-12 alanine-valine transaminase, transaminase C. This inhibition, along with the inhibition of transaminase B, accounted for the isoleucine-plus-valine requirement of E. coli in the presence of beta-chloro-L-alanine.

  6. Structure Determination of Mycobacterium tuberculosis Serine Protease Hip1 (Rv2224c)

    Energy Technology Data Exchange (ETDEWEB)

    Naffin-Olivos, Jacqueline L.; Daab, Andrew; White, Andre; Goldfarb, Nathan E.; Milne, Amy C.; Liu, Dali; Baikovitz, Jacqueline; Dunn, Ben M.; Rengarajan, Jyothi; Petsko, Gregory A.; Ringe, Dagmar

    2017-04-07

    The Mycobacterium tuberculosis (Mtb) serine protease Hip1 (hydrolase important for pathogenesis; Rv2224c) promotes tuberculosis (TB) pathogenesis by impairing host immune responses through proteolysis of a protein substrate, Mtb GroEL2. The cell surface localization of Hip1 and its immunomodulatory functions make Hip1 a good drug target for new adjunctive immune therapies for TB. Here, we report the crystal structure of Hip1 to a resolution of 2.6 Å and the kinetic studies of the enzyme against model substrates and the protein GroEL2. The structure shows a two-domain protein, one of which contains the catalytic residues that are the signature of a serine protease. Surprisingly, a threonine is located within the active site close enough to hydrogen bond with the catalytic residues Asp463 and His490. Mutation of this residue, Thr466, to alanine established its importance for function. Our studies provide insights into the structure of a member of a novel family of proteases. Knowledge of the Hip1 structure will aid in designing inhibitors that could block Hip1 activity

  7. Pdx1 is post-translationally modified in vivo and serine 61 is the principal site of phosphorylation

    DEFF Research Database (Denmark)

    Frogne, Thomas; Sylvestersen, Kathrine Beck; Kubicek, Stefan

    2012-01-01

    signaling. Several studies have shown that post-translational modifications are regulating Pdx1 activity through intracellular localization and binding to co-factors. Understanding the signaling cues converging on Pdx1 and modulating its activity is therefore an attractive approach in diabetes treatment. We...... alanine scanning and mass spectrometry we map this phosphorylation to serine 61 in both Min6 cells and in exogenous Pdx1 over-expressed in HEK293 cells. A single phosphorylation is also present in cultured islets but it remains unaffected by changes in glucose levels. It is present during embryogenesis...

  8. Conformational Structure of Tyrosine, Tyrosyl-Glycine, and Tyrosyl-Glycyl-Glycine by Double Resonance Spectroscopy

    Science.gov (United States)

    Abo-Riziq, Ali; Grace, Louis; Crews, Bridgit; Callahan, Michael P,; van Mourik, Tanja; de Vries, Mattanjah S,

    2011-01-01

    We investigated the variation in conformation for the amino acid tyrosine (Y), alone and in the small peptides tyrosine-glycine (YC) and tyrosine-glycine-glycine (YGG), in the gas phase by using UV-UV and IR-UV double resonance spectroscopy and density functional theory calculations. For tyrosine we found seven different conformations, for YG we found four different conformations, and for YGG we found three different conformations. As the peptides get larger, we observe fewer stable conformers, despite the increasing complexity and number of degrees of freedom. We find structural trends similar to those in phenylalanine-glycine glycine (FGG) and tryptophan-glycine-glycine (WGG)j however) the effect of dispersive forces in FGG for stabilizing a folded structure is replaced by that of hydrogen bonding in YGG.

  9. Population-specific gene expression in the plant pathogenic nematode Heterodera glycines exists prior to infection and during the onset of a resistant or susceptible reaction in the roots of the Glycine max genotype Peking

    Directory of Open Access Journals (Sweden)

    Alkharouf Nadim W

    2009-03-01

    Full Text Available Abstract Background A single Glycine max (soybean genotype (Peking reacts differently to two different populations of Heterodera glycines (soybean cyst nematode within the first twelve hours of infection during resistant (R and susceptible (S reactions. This suggested that H. glycines has population-specific gene expression signatures. A microarray analysis of 7539 probe sets representing 7431 transcripts on the Affymetrix® soybean GeneChip® were used to identify population-specific gene expression signatures in pre-infective second stage larva (pi-L2 prior to their infection of Peking. Other analyses focused on the infective L2 at 12hours post infection (i-L212h, and the infective sedentary stages at 3days post infection (i-L23d and 8days post infection (i-L2/L38d. Results Differential expression and false discovery rate (FDR analyses comparing populations of pi-L2 (i.e., incompatible population, NL1-RHg to compatible population, TN8 identified 71 genes that were induced in NL1-RHg as compared to TN8. These genes included putative gland protein G23G12, putative esophageal gland protein Hgg-20 and arginine kinase. The comparative analysis of pi-L2 identified 44 genes that were suppressed in NL1-RHg as compared to TN8. These genes included a different Hgg-20 gene, an EXPB1 protein and a cuticular collagen. By 12 h, there were 7 induced genes and 0 suppressed genes in NL1-RHg. By 3d, there were 9 induced and 10 suppressed genes in NL1-RHg. Substantial changes in gene expression became evident subsequently. At 8d there were 13 induced genes in NL1-RHg. This included putative gland protein G20E03, ubiquitin extension protein, putative gland protein G30C02 and β-1,4 endoglucanase. However, 1668 genes were found to be suppressed in NL1-RHg. These genes included steroid alpha reductase, serine proteinase and a collagen protein. Conclusion These analyses identify a genetic expression signature for these two populations both prior to and subsequently

  10. Studies of Environmental Risk Factors in Amyotrophic Lateral Sclerosis (ALS) and a Phase I Clinical Trial of L-Serine.

    Science.gov (United States)

    Bradley, Walter G; Miller, R X; Levine, T D; Stommel, E W; Cox, P A

    2018-01-01

    β-N-Methylamino-L-alanine (BMAA) has been linked to Guam ALS/PDC and shown to produce neurodegeneration in vitro and in vivo (Drosophila, mice, rats, primates). BMAA misincorporation into neuroproteins produces protein misfolding and is inhibited by L-serine. Case-control studies in Northern New England indicate that living near to water-bodies with cyanobacterial blooms increases the risk of developing amyotrophic lateral sclerosis (ALS). The distribution of addresses of ALS cases in New Hampshire, Vermont, and Florida was compared to that of controls. Areas of statistically significantly increased numbers of ALS cases were examined for sources of environmental toxins. A phase I trial of oral L-serine was performed in 20 ALS patients (0.5 to 15 g twice daily). Safety and tolerability were assessed by comparing the rate of deterioration with 430 matched placebo controls. The distribution of residential addresses of ALS cases in New England and Florida revealed many areas where the age- and gender-adjusted frequency of ALS was greater than expected (P ALS patients suggests that residential exposure to environmental pollutants may play an important role in the etiology of ALS. L-Serine in doses up to 15 g twice daily appears to be safe in patients with ALS. Exploratory studies of efficacy suggested that L-serine might slow disease progression. A phase II trial is planned.

  11. Production of D-alanine from DL-alanine using immobilized cells of Bacillus subtilis HLZ-68.

    Science.gov (United States)

    Zhang, Yangyang; Li, Xiangping; Zhang, Caifei; Yu, Xiaodong; Huang, Fei; Huang, Shihai; Li, Lianwei; Liu, Shiyu

    2017-09-13

    Immobilized cells of Bacillus subtilis HLZ-68 were used to produce D-alanine from DL-alanine by asymmetric degradation. Different compounds such as polyvinyl alcohol and calcium alginate were employed for immobilizing the B. subtilis HLZ-68 cells, and the results showed that cells immobilized using a mixture of these two compounds presented higher L-alanine degradation activity, when compared with free cells. Subsequently, the effects of different concentrations of polyvinyl alcohol and calcium alginate on L-alanine consumption were examined. Maximum L-alanine degradation was exhibited by cells immobilized with 8% (w/v) polyvinyl alcohol and 2% (w/v) calcium alginate. Addition of 400 g of DL-alanine (200 g at the beginning of the reaction and 200 g after 30 h of incubation) into the reaction solution at 30 °C, pH 6.0, aeration of 1.0 vvm, and agitation of 400 rpm resulted in complete L-alanine degradation within 60 h, leaving 185 g of D-alanine in the reaction solution. The immobilized cells were applied for more than 15 cycles of degradation and a maximum utilization rate was achieved at the third cycle. D-alanine was easily extracted from the reaction solution using cation-exchange resin, and the chemical and optical purity of the extracted D-alanine was 99.1 and 99.6%, respectively.

  12. Synthesis and distribution of N-benzyloxycarbonyl-[14C]-glycine, a lipophilic derivative of glycine

    International Nuclear Information System (INIS)

    Lambert, D.M.; Gallez, Bernard; Poupaert, J.H.

    1995-01-01

    N-benzyloxycarbonyl[ 14 C]-glycine, a lipophilic derivative of glycine exhibiting anticonvulsant properties, was prepared in one step from [U- 14 C] glycine and benzyl chloroformate in alkali medium. a comparative study of biodistribution was carried on mice between this compound and the parent amino-acid after intravenous administration. Dimethylsulfoxide was used as injection vehicle for N-benzyloxycarbonylglycine. The influence of this injection vehicle was studied comparing glycine injected in a saline solution and glycine co-administered with dimethylsulfoxide. No significant difference was found between these two treatments. Compared to glycine, N-benzyloxycarbonylglycine reached quickly the central nervous system and exhibited an enhanced brain penetration index, 13-fold superior to the parent aminoacid value. (Author)

  13. A study of the irradiation temperature coefficient for L-alanine and DL-alanine dosemeters

    International Nuclear Information System (INIS)

    Desrosiers, M. F.; Lin, M.; Cooper, S. L.; Cui, Y.; Chen, K.

    2006-01-01

    Alanine dosimetry is now well established both as a reference and routine dosemeter for industrial irradiation processing. Accurate dosimetry under the relatively harsh conditions of industrial processing requires a characterisation of the parameters that influence the dosemeter response. The temperature of the dosemeter during irradiation is a difficult quantity to measure so that the accuracy of the temperature coefficient that governs the dosemeter response becomes a critical factor. Numerous publications have reported temperature coefficients for several types of alanine dosemeters. The observed differences in the measured values were commonly attributed to the differences in the polymer binder or the experimental design of the measurement. However, the data demonstrated a consistent difference in the temperature coefficients between L-alanine and DL-alanine. Since there were no commonalities in the dosemeter composition or the measurement methods applied, a clear conclusion is not possible. To resolve this issue, the two isomeric forms of alanine dosemeters were prepared and irradiated in an identical manner. The results indicated that the DL-alanine temperature coefficient is more than 50% higher than the L-alanine temperature coefficient. (authors)

  14. Initial organic products of fixation of [13N]dinitrogen by root nodules of soybean (Glycine max)

    International Nuclear Information System (INIS)

    Meeks, J.C.; Wolk, C.P.; Schilling, N.; Shaffer, P.W.; Avissar, Y.; Chien, W.S.

    1978-01-01

    When detached soybean Glycine max (L.) Merr. cv. Hark, nodules assimilate ( 13 N)N 2 , the initial organic product of fixation is glutamine; glutamate becomes more highly radioactive than glutamine within 1 minute; 13 N in alanine becomes detectable at 1 minute of fixation and increases rapidly between 1 and 2 minutes. After 15 minutes of fixation, the major 13 N-labeled organic products in both detached and attached nodules are glutamate and alanine, plus, in the case of attached nodules, an unidentified substance, whereas ( 13 N)glutamine comprises only a small fraction of organic 13 N, and very little 13 N is detected in asparagine. The fixation of ( 13 N)N 2 into organic products was inhibited more than 99 percent by C 2 H 2 (10 percent, v/v). The results support the idea that the glutamine synthetase-glutamate synthase pathway is the primary route for assimilation of fixed nitrogen in soybean nodules

  15. Site-selective modification of peptides: From "customizable units" to novel α-aryl and α-alkyl glycine derivatives, and components of branched peptides.

    Science.gov (United States)

    Romero-Estudillo, Iván; Saavedra, Carlos; Boto, Alicia; Álvarez, Eleuterio

    2015-09-01

    The creation of peptide libraries by site-selective modification of a few peptide substrates would increase the efficiency of discovery processes, but still is a real synthetic challenge. The site-selective modification of small peptides at serine or threonine residues, by using a short scission-addition procedure, allows the preparation of peptides with unnatural α-aryl glycines. In a similar way, the scission of hydroxyproline residues is the key step in the production of optically pure α-alkyl glycines which are precursors or components of branched peptides. With these versatile processes, a single peptide can be transformed into a variety of peptide derivatives. The process takes place under mild conditions, and good global yields are obtained. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 104: 650-662, 2015. © 2015 Wiley Periodicals, Inc.

  16. Secretion of d-alanine by Escherichia coli.

    Science.gov (United States)

    Katsube, Satoshi; Sato, Kazuki; Ando, Tasuke; Isogai, Emiko; Yoneyama, Hiroshi

    2016-07-01

    Escherichia coli has an l-alanine export system that protects the cells from toxic accumulation of intracellular l-alanine in the presence of l-alanyl-l-alanine (l-Ala-l-Ala). When a DadA-deficient strain was incubated with 6.0 mM l-Ala-l-Ala, we detected l-alanine and d-alanine using high-performance liquid chromatography (HPLC) analysis at a level of 7.0 mM and 3.0 mM, respectively, after 48 h incubation. Treatment of the culture supernatant with d-amino acid oxidase resulted in the disappearance of a signal corresponding to d-alanine. Additionally, the culture supernatant enabled a d-alanine auxotroph to grow without d-alanine supplementation, confirming that the signal detected by HPLC was authentic d-alanine. Upon introduction of an expression vector harbouring the alanine racemase genes, alr or dadX, the extracellular level of d-alanine increased to 11.5 mM and 8.5 mM, respectively, under similar conditions, suggesting that increased metabolic flow from l-alanine to d-alanine enhanced d-alanine secretion. When high-density DadA-deficient cells preloaded with l-Ala-l-Ala were treated with 20 µM carbonyl cyanide m-chlorophenyl hydrazone (CCCP), secretion of both l-alanine and d-alanine was enhanced ~twofold compared with that in cells without CCCP treatment. In contrast, the ATPase inhibitor dicyclohexylcarbodiimide did not exert such an effect on the l-alanine and d-alanine secretion. Furthermore, inverted membrane vesicles prepared from DadA-deficient cells lacking the l-alanine exporter AlaE accumulated [3H]D-alanine in an energy-dependent manner. This energy-dependent accumulation of [3H]D-alanine was strongly inhibited by CCCP. These results indicate that E. coli has a transport system(s) that exports d-alanine and that this function is most likely modulated by proton electrochemical potential.

  17. Comparison of alanine dosimeters using silicone as their binder to a commercial, polystyrene-bound, alanine dosimeter

    International Nuclear Information System (INIS)

    Galindo, S.; Urena-Nunez, F.

    1997-01-01

    The feasibility of practical boron-containing alanine ESR dosimeters for gamma-neutron mixed field irradiation dosimeters depends in part on whether the γ response characteristics of these silicone-bound dosimeters are comparable to those of a commercially available dosimeter that has been used by the International Atomic Energy Agency (International Dose Assurance Service) as a transfer reference dosimeter. This work presents the results of the comparison of 3 batches of silicone-bound alanine dosimeters. The first batch consists of a mixture of alanine and boric acid; the second, alanine and borax; and the last contains only alanine. Results indicate that γ response characteristics of the silicone-bound samples are comparable to those of the commercial, polystyrene-bound, alanine dosimeter and that silicone has a strong potential as a binding substance for alanine ESR dosimetry. (Author)

  18. Effects of Glycine, Water, Ammonia, and Ammonium Bicarbonate on the Oligomerization of Methionine

    Science.gov (United States)

    Huang, Rui; Furukawa, Yoshihiro; Otake, Tsubasa; Kakegawa, Takeshi

    2017-06-01

    The abiotic oligomerization of amino acids may have created primordial, protein-like biological catalysts on the early Earth. Previous studies have proposed and evaluated the potential of diagenesis for the amino acid oligomerization, simulating the formation of peptides that include glycine, alanine, and valine, separately. However, whether such conditions can promote the formation of peptides composed of multiple amino acids remains unclear. Furthermore, the chemistry of pore water in sediments should affect the oligomerization and degradation of amino acids and oligomers, but these effects have not been studied extensively. In this study, we investigated the effects of water, ammonia, ammonium bicarbonate, pH, and glycine on the oligomerization and degradation of methionine under high pressure (150 MPa) and high temperature conditions (175 °C) for 96 h. Methionine is more difficult to oligomerize than glycine and methionine dimer was formed in the incubation of dry powder of methionine. Methionine oligomers as long as trimers, as well as methionylglycine and glycylmethionine, were formed under every condition with these additional compounds. Among the compounds tested, the oligomerization reaction rate was accelerated by the presence of water and by an increase in pH. Ammonia also increased the oligomerization rate but consumed methionine by side reactions and resulted in the rapid degradation of methionine and its peptides. Similarly, glycine accelerated the oligomerization rate of methionine and the degradation of methionine, producing water, ammonia, and bicarbonate through its decomposition. With Gly, heterogeneous dimers (methionylglycine and glycylmethionine) were formed in greater amounts than with other additional compounds although smaller amount of these heterogeneous dimers were formed with other additional compounds. These results suggest that accelerated reaction rates induced by water and co-existing reactive compounds promote the oligomerization

  19. Selection of D-Alanine-Tolerant Rice Cells

    OpenAIRE

    Hisashi, Manabe; Koji, Ohira; Aizu Junior College of Fukushima Prefecture; Department of Agricultural Chemistry, Faculty of Agriculture, Tohoku University

    1984-01-01

    By repeating subculture of rice cells (parent cells) in a D-alanine containing medium, we could select rice cells which grew well in the D-alanine medium. The D-alanine-tolerant cells absorbed a fairly small amount of D-alanine from the medium and did not accumulate much D-alanine in the cells. Aggregation of D-alanine-tolerant cells was greater than that of parent cells. D-Alanine metabolism of D-alanine.-tolerant cells did not increase in comparison with parent cells.

  20. Method for the production of l-serine using genetically engineered microorganisms deficient in serine degradation pathways

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention generally relates to the microbiological industry, and specifically to the production of L-serine using genetically modified bacteria. The present invention provides genetically modified microorganisms, such as bacteria, wherein the expression of genes encoding for enzymes...... concentrations of serine. The present invention also provides methods for the production of L-serine or L-serine derivative using such genetically modified microorganisms....

  1. Synthesis and distribution of N-benzyloxycarbonyl-[{sup 14}C]-glycine, a lipophilic derivative of glycine

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, D.M.; Gallez, Bernard; Poupaert, J.H. [Universite Catholique de Louvain, Brussels (Belgium). Dept. des Sciences Pharmaceutiques

    1995-12-31

    N-benzyloxycarbonyl[{sup 14}C]-glycine, a lipophilic derivative of glycine exhibiting anticonvulsant properties, was prepared in one step from [U-{sup 14}C] glycine and benzyl chloroformate in alkali medium. a comparative study of biodistribution was carried on mice between this compound and the parent amino-acid after intravenous administration. Dimethylsulfoxide was used as injection vehicle for N-benzyloxycarbonylglycine. The influence of this injection vehicle was studied comparing glycine injected in a saline solution and glycine co-administered with dimethylsulfoxide. No significant difference was found between these two treatments. Compared to glycine, N-benzyloxycarbonylglycine reached quickly the central nervous system and exhibited an enhanced brain penetration index, 13-fold superior to the parent aminoacid value. (Author).

  2. Comparison of EPR response of alanine and Gd₂O₃-alanine dosimeters exposed to TRIGA Mainz reactor.

    Science.gov (United States)

    Marrale, M; Schmitz, T; Gallo, S; Hampel, G; Longo, A; Panzeca, S; Tranchina, L

    2015-12-01

    In this work we report some preliminary results regarding the analysis of electron paramagnetic resonance (EPR) response of alanine pellets and alanine pellets added with gadolinium used for dosimetry at the TRIGA research reactor in Mainz, Germany. Two set-ups were evaluated: irradiation inside PMMA phantom and irradiation inside boric acid phantom. We observed that the presence of Gd2O3 inside alanine pellets increases the EPR signal by a factor of 3.45 and 1.24 in case of PMMA and boric acid phantoms, respectively. We can conclude that in the case of neutron beam with a predominant thermal neutron component the addition of gadolinium oxide can significantly improve neutron sensitivity of alanine pellets. Monte Carlo (MC) simulations of both response of alanine and Gd-added alanine pellets with FLUKA code were performed and a good agreement was achieved for pure alanine dosimeters. For Gd2O3-alanine deviations between MC simulations and experimental data were observed and discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Neonatal disruption of serine racemase causes schizophrenia-like behavioral abnormalities in adulthood: clinical rescue by d-serine.

    Directory of Open Access Journals (Sweden)

    Hiroko Hagiwara

    Full Text Available D-Serine, an endogenous co-agonist of the N-methyl-D-aspartate (NMDA receptor, is synthesized from L-serine by serine racemase (SRR. Given the role of D-serine in both neurodevelopment and the pathophysiology of schizophrenia, we examined whether neonatal disruption of D-serine synthesis by SRR inhibition could induce behavioral abnormalities relevant to schizophrenia, in later life.Neonatal mice (7-9 days were injected with vehicle or phenazine methosulfate (Met-Phen: 3 mg/kg/day, an SRR inhibitor. Behavioral evaluations, such as spontaneous locomotion, novel object recognition test (NORT, and prepulse inhibition (PPI were performed at juvenile (5-6 weeks old and adult (10-12 weeks old stages. In addition, we tested the effects of D-serine on PPI deficits in adult mice after neonatal Met-Phen exposure. Finally, we assessed whether D-serine could prevent the onset of schizophrenia-like behavior in these mice. Neonatal Met-Phen treatment reduced D-serine levels in the brain, 24 hours after the final dose. Additionally, this treatment caused behavioral abnormalities relevant to prodromal symptoms in juveniles and to schizophrenia in adults. A single dose of D-serine improved PPI deficits in adult mice. Interestingly, chronic administration of D-serine (900 mg/kg/day from P35 to P70 significantly prevented the onset of PPI deficits after neonatal Met-Phen exposure.This study shows that disruption of D-serine synthesis during developmental stages leads to behavioral abnormalities relevant to prodromal symptoms and schizophrenia, in later life. Furthermore, early pharmacological intervention with D-serine may prevent the onset of psychosis in adult.

  4. Effect of Exogenous _D-Alanine on _D-Alanyl-_D-alanine Content in Leaf Blades of Oryza australiensis Domin

    OpenAIRE

    Hisashi, Manabe; Aizu Junior College of Fukushima Prefecture

    1986-01-01

    In seedlings of Oryza australiensis Domin (W0008), most of the D-alanyl-D-alanine was distributed in the leaf blades. In excised leaf blades of W0008, exogenous D-alanine was incorporated into D-alanyl-D-alanine irrespective of the light condition as in Sasanishiki. With cultivation in D-alanine medium for several days, the D-alanyl-D-alanine content in W0008 leaf blades was found to increase, but no other D-alanine-containing dipeptides such as D-alanylglycine or D-alanyl-L-alanine were dete...

  5. Orally administered L-arginine and glycine are highly effective against acid reflux esophagitis in rats

    Science.gov (United States)

    Nagahama, Kenji; Nishio, Hikaru; Yamato, Masanori; Takeuchi, Koji

    2012-01-01

    Summary Background Reflux esophagitis is caused mainly by excessive exposure of the mucosa to gastric contents. In the present study, we examined the effect of several amino acids on acid reflux esophagitis in rats. Material/Methods After 18 h of fasting, acid reflux esophagitis was induced by ligating both the pylorus and the transitional region between the forestomach and the corpus under ether anesthesia, and the animals were killed 4 h later. The severity of esophagitis was reduced by the oral administration of omeprazole, a proton pump inhibitor, or pepstatin, a specific pepsin inhibitor. Results The development of esophageal lesions was dose-dependently prevented by L-arginine and glycine, given intragastrically (i.g.) after the ligation, with complete inhibition obtained at 250 mg/kg and 750 mg/kg, respectively, and these effects were not influenced by the prior s.c. administration of indomethacin or L-NAME. By contrast, both L-alanine and L-glutamine given i.g. after the ligation aggravated these lesions in a dose-dependent manner. These amino acids had no effect on acid secretion but increased the pH of the gastric contents to 1.8~2.3 due to their buffering action. Conclusions The results confirmed an essential role for acid and pepsin in the pathogenesis of acid reflux esophagitis in the rat model and further suggested that various amino acids affect the severity of esophagitis in different ways, due to yet unidentified mechanisms; L-alanine and L-glutamine exert a deleterious effect on the esophagitis, while L-arginine and glycine are highly protective, independent of endogenous prostaglandins and nitric oxide. PMID:22207112

  6. Glycine Transporter Inhibitor Attenuates the Psychotomimetic Effects of Ketamine in Healthy Males: Preliminary Evidence

    Science.gov (United States)

    D'Souza, Deepak Cyril; Singh, Nagendra; Elander, Jacqueline; Carbuto, Michelle; Pittman, Brian; de Haes, Joanna Udo; Sjogren, Magnus; Peeters, Pierre; Ranganathan, Mohini; Schipper, Jacques

    2012-01-01

    Enhancing glutamate function by stimulating the glycine site of the NMDA receptor with glycine, -serine, or with drugs that inhibit glycine reuptake may have therapeutic potential in schizophrenia. The effects of a single oral dose of cis-N-methyl-N-(6-methoxy-1-phenyl-1,2,3,4-tetrahydronaphthalen-2-ylmethyl) amino-methylcarboxylic acid hydrochloride (Org 25935), a glycine transporter-1 (GlyT1) inhibitor, and placebo pretreatment on ketamine-induced schizophrenia-like psychotic symptoms, perceptual alterations, and subjective effects were evaluated in 12 healthy male subjects in a randomized, counter-balanced, within-subjects, crossover design. At 2.5 h after administration of the Org 25935 or placebo, subjects received a ketamine bolus and constant infusion lasting 100 min. Psychotic symptoms, perceptual, and a number of subjective effects were assessed repeatedly before, several times during, and after completion of ketamine administration. A cognitive battery was administered once per test day. Ketamine produced behavioral, subjective, and cognitive effects consistent with its known effects. Org 25935 reduced the ketamine-induced increases in measures of psychosis (Positive and Negative Syndrome Scale (PANSS)) and perceptual alterations (Clinician Administered Dissociative Symptoms Scale (CADSS)). The magnitude of the effect of Org 25935 on ketamine-induced increases in Total PANSS and CADSS Clinician-rated scores was 0.71 and 0.98 (SD units), respectively. None of the behavioral effects of ketamine were increased by Org 25935 pretreatment. Org 25935 worsened some aspects of learning and delayed recall, and trended to improve choice reaction time. This study demonstrates for the first time in humans that a GlyT1 inhibitor reduces the effects induced by NMDA receptor antagonism. These findings provide preliminary support for further study of the antipsychotic potential of GlyT1 inhibitors. PMID:22113087

  7. Amino acid transport across the tonoplast of vacuoles isolated from barley mesophyll protoplasts: Uptake of alanine, leucine, and glutamine

    International Nuclear Information System (INIS)

    Dietz, K.J.; Jaeger, R.; Kaiser, G.; Martinoia, E.

    1990-01-01

    Mesophyll protoplasts from leaves of well-fertilized barley (Hordeum vulgare L.) plants contained amino acids at concentrations as high as 120 millimoles per liter. With the exception of glutamic acid, which is predominantly localized in the cytoplasm, a major part of all other amino acids was contained inside the large central vacuole. Alanine, leucine, and glutamine are the dominant vacuolar amino acids in barley. Their transport into isolated vacuoles was studied using 14 C-labeled amino acids. Uptake was slow in the absence of ATP. A three- to sixfold stimulation of uptake was observed after addition of ATP or adenylyl imidodiphosphate an ATP analogue not being hydrolyzed by ATPases. Other nucleotides were ineffective in increasing the rate of uptake. ATP-Stimulated amino acid transport was not dependent on the transtonoplast pH or membrane potential. p-Chloromercuriphenylsulfonic acid and n-ethyl maleimide increased transport independently of ATP. Neutral amino acids such as valine or leucine effectively decreased the rate of alanine transport. Glutamine and glycine were less effective or not effective as competitive inhibitors of alanine transport. The results indicate the existence of a uniport translocator specific for neutral or basic amino acids that is under control of metabolic effectors

  8. 21 CFR 172.540 - DL-Alanine.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true DL-Alanine. 172.540 Section 172.540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Agents and Related Substances § 172.540 DL-Alanine. DL-Alanine (a racemic mixture of D- and L-alanine...

  9. Amino acid profiles of young adults differ by sex, body mass index and insulin resistance.

    Science.gov (United States)

    Guevara-Cruz, M; Vargas-Morales, J M; Méndez-García, A L; López-Barradas, A M; Granados-Portillo, O; Ordaz-Nava, G; Rocha-Viggiano, A K; Gutierrez-Leyte, C A; Medina-Cerda, E; Rosado, J L; Morales, J C; Torres, N; Tovar, A R; Noriega, L G

    2018-04-01

    An increase in plasma branched-chain amino acids is associated with a higher risk of developing type 2 diabetes and cardiovascular diseases. However, little is known about the basal plasma amino acid concentrations in young adults. Our aim was to determine the plasma amino acid profiles of young adults and to evaluate how these profiles were modified by sex, body mass index (BMI) and insulin resistance (IR). We performed a transversal study with 608 Mexican young adults aged 19.9 ± 2.4 years who were applicants to the Universidad Autónoma de San Luis Potosí. The subjects underwent a physical examination and provided a clinical history and a blood sample for biochemical, hormonal and amino acid analyses. The women had higher levels of arginine, aspartate and serine and lower levels of α-aminoadipic acid, cysteine, isoleucine, leucine, methionine, proline, tryptophan, tyrosine, urea and valine than the men. The obese subjects had higher levels of alanine, aspartate, cysteine, ornithine, phenylalanine, proline and tyrosine and lower levels of glycine, ornithine and serine than the normal weight subjects. Subjects with IR (defined as HOMA > 2.5) had higher levels of arginine, alanine, aspartate, isoleucine, leucine, phenylalanine, proline, tyrosine, taurine and valine than the subjects without IR. Furthermore, we identified two main groups in the subjects with obesity and/or IR; one group was composed of amino acids that positively correlated with the clinical, biochemical and hormonal parameters, whereas the second group exhibited negative correlations. This study demonstrates that young adults with obesity or IR have altered amino acid profiles characterized by an increase in alanine, aspartate, proline and tyrosine and a decrease in glycine. Copyright © 2018 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II

  10. 21 CFR 582.5118 - Alanine.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Alanine. 582.5118 Section 582.5118 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS... § 582.5118 Alanine. (a) Product. Alanine (L- and DL-forms). (b) Conditions of use. This substance is...

  11. Draft genome sequence of Micrococcus luteus strain O'Kane implicates metabolic versatility and the potential to degrade polyhydroxybutyrates.

    Science.gov (United States)

    Hanafy, Radwa A; Couger, M B; Baker, Kristina; Murphy, Chelsea; O'Kane, Shannon D; Budd, Connie; French, Donald P; Hoff, Wouter D; Youssef, Noha

    2016-09-01

    Micrococcus luteus is a predominant member of skin microbiome. We here report on the genomic analysis of Micrococcus luteus strain O'Kane that was isolated from an elevator. The partial genome assembly of Micrococcus luteus strain O'Kane is 2.5 Mb with 2256 protein-coding genes and 62 RNA genes. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of glucose, galactose, fructose, mannose, alanine, aspartate, asparagine, glutamate, glutamine, glycine, serine, cysteine, methionine, arginine, proline, histidine, phenylalanine, and fatty acids. Genomic comparison to other M. luteus representatives identified the potential to degrade polyhydroxybutyrates, as well as several antibiotic resistance genes absent from other genomes.

  12. Analysis of Amino Acid Residues of Potential Importance for Phosphati-dylserine Specificity of P4-type ATPase ATP8A2

    DEFF Research Database (Denmark)

    Mogensen, Louise; Vestergaard, Anna Lindeløv; Mikkelsen, Stine

    The asymmetric structure of the plasma membrane is maintained through internalization of phos-pholipids by the family of P4-ATPases by a poorly characterized mechanism. Studies in yeast point towards a non-classical pathway involving important residues of a two-gate mechanism [1]. Glycine-230...... 302 of ATP8A2 with alanine (N302A), tyrosine (N302Y) and serine (N302S). Furthermore, a triple mutant of ATP8A2 (Q95GQ96AN302S) was studied to reveal any cooperativity between the two gates, as observed in yeast [1]. The affinities of the mutants for phosphatidylserine and phosphatidylethanolamine...

  13. Formation of amino acids by cobalt-60 irradiation of hydrogen cyanide solutions

    Science.gov (United States)

    Sweeney, M. A.; Toste, A. P.; Ponnamperuma, C.

    1976-01-01

    Experiments were conducted to study the pathway for the prebiotic origin of amino acids from hydrogen cyanide (HCN) under the action of ionizing radiation considered as an effective source of energy on the primitive earth. The irradiations were performed in a cobalt-60 source with a dose rate of 200,000 rad/hr. Seven naturally occurring amino acids are identified among the products formed by the hydrolysis of gamma-irradiated solutions of HCN: glycine, alanine, valine, serine, threonine, aspartic acid, and glutamic acid. The identity of these amino acids is established by gas chromatography and mass spectrometry. Control experiments provided evidence that the amino acids are not the result of contamination.

  14. Functional Characterization of Alanine Racemase from Schizosaccharomyces pombe: a Eucaryotic Counterpart to Bacterial Alanine Racemase

    OpenAIRE

    Uo, Takuma; Yoshimura, Tohru; Tanaka, Naotaka; Takegawa, Kaoru; Esaki, Nobuyoshi

    2001-01-01

    Schizosaccharomyces pombe has an open reading frame, which we named alr1+, encoding a putative protein similar to bacterial alanine racemase. We cloned the alr1+ gene in Escherichia coli and purified the gene product (Alr1p), with an Mr of 41,590, to homogeneity. Alr1p contains pyridoxal 5′-phosphate as a coenzyme and catalyzes the racemization of alanine with apparent Km and Vmax values as follows: for l-alanine, 5.0 mM and 670 μmol/min/mg, respectively, and for d-alanine, 2.4 mM and 350 μmo...

  15. Transport of the alpha-amino-mono-carboxylic acid L-alanine by the beta-alanine carrier of the rabbit ileum

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Munck, B G

    1987-01-01

    The proposal that the beta-alanine carrier of the rabbit ileum is a high affinity carrier of the neutral amino acids was examined by means of measurements of influx across the brush border membrane of the intact epithelium using L-alanine as a representative of the neutral amino acids. Confirming...... the proposal, evidence was provided for mutual competitive inhibition between beta-alanine and L-alanine; and it was also demonstrated that a process contributes to the influx of L-alanine, which is characterized by a maximum rate of transport equal to that of beta-alanine and a Kt, which is equal to the Ki...... of L-alanine against the influx of beta-alanine. In the concentration range 0.01 to 0.125 mM the influx of L-alanine was found to be linearly related to the concentration indicating a significant unstirred layer influence on present and previous estimates of the Kt values for influx of amino acids...

  16. Highly Efficient Fumed Silica Nanoparticles for Peptide Bond Formation: Converting Alanine to Alanine Anhydride.

    Science.gov (United States)

    Guo, Chengchen; Jordan, Jacob S; Yarger, Jeffery L; Holland, Gregory P

    2017-05-24

    In this work, thermal condensation of alanine adsorbed on fumed silica nanoparticles is investigated using thermal analysis and multiple spectroscopic techniques, including infrared (IR), Raman, and nuclear magnetic resonance (NMR) spectroscopies. Thermal analysis shows that adsorbed alanine can undergo thermal condensation, forming peptide bonds within a short time period and at a lower temperature (∼170 °C) on fumed silica nanoparticle surfaces than that in bulk (∼210 °C). Spectroscopic results further show that alanine is converted to alanine anhydride with a yield of 98.8% during thermal condensation. After comparing peptide formation on solution-derived colloidal silica nanoparticles, it is found that fumed silica nanoparticles show much better efficiency and selectivity than solution-derived colloidal silica nanoparticles for synthesizing alanine anhydride. Furthermore, Raman spectroscopy provides evidence that the high efficiency for fumed silica nanoparticles is likely related to their unique surface features: the intrinsic high population of strained ring structures present at the surface. This work indicates the great potential of fumed silica nanoparticles in synthesizing peptides with high efficiency and selectivity.

  17. Molecular basis of adult-onset and chronic GM2 gangliosidoses in patients of Ashkenazi Jewish origin: Substitution of serine for glycine at position 269 of the α-subunit of β-hexosaminidase

    International Nuclear Information System (INIS)

    Paw, B.H.; Kaback, M.M.; Neufeld, E.F.

    1989-01-01

    Chronic and adult-onset G M2 gangliosidoses are neurological disorders caused by marked deficiency of the A isoenzyme of β-hexosaminidase; they occur in the Ashkenazi Jewish population, though less frequently than classic (infantile) Tay-Sachs disease. Earlier biosynthetic studies had identified a defective α-subunit that failed to associate with the β-subunit. The authors have now found a guanosine to adenosine transition at the 3' end of exon 7, which causes substitution of serine for glycine at position 269 of the α-subunit. An RNase protection assay was used to localize the mutation to a segment of mRNA from fibroblasts of a patient with the adult-onset disorder. That segment of mRNA (after reverse transcription) and a corresponding segment of genomic DNA were amplified by the polymerase chain reaction and sequenced by the dideoxy method. The sequence analysis, together with an assay based on the loss of a ScrFI restriction site, showed that the patient was a compound heterozygote who had inherited the 269 (Gly → Ser) mutation from his father and an allelic null mutation from his mother. The 269 (Gly → Ser) mutation, in compound heterozygosity with a presumed null allele, was also found in fetal fibroblasts with an association-defective phenotype and in cells from five patients with chronic G M2 gangliosidosis

  18. Procedure for preparation of 3-fluor-D-alanine, 2-deutero-3-fluor-D-alanine and 2,3,3-trideutero-3-fluor-D-alanine and their salts

    International Nuclear Information System (INIS)

    Kollonitsch, J.; Kahan, F.M.

    1971-01-01

    Procedures for the preparation of 3-fluor-D-alanine, 2-deutero-3-fluor-D-alanine and 2,3,3-trideutero-3-fluor-D-alanine, and salts of these compounds, are described. These new compounds are useful antibacterial substances not only applicable in the disinfection of pharmaceutical, dental and medical equipment, but also in the treatment of diseases caused by bacteria, and may be administered orally. While 3-fluor-L-alanine metabolises rapidly with toxic results, 3-fluor-D-alanine is much more slowly broken down in vivo and is not harmful in normal doses. Further it has been found that deuteration gives new deutero-analogues which are less subject to metabolic breaking down and still retain the antibacterial strength of the original compound. The in vivo activity is thereby increased and maintained. (JIW)

  19. Asparagine and glycine metabolism in rat liver mitochondria and in mouse L5178Y lymphoma cells resistant or sensitive to the anticancer drug L-asparaginase

    Energy Technology Data Exchange (ETDEWEB)

    Keefer, J.F. Jr.

    1986-01-01

    Rat liver mitochondrial asparagine was found to be degraded via an aminotransferase and omega-amidase. Evidence includes oxaloacetate production from asparagine only when glyoxylate was added and production of radiolabeled ..cap alpha..-ketosuccinamate via metabolism of (U-/sup 14/C)asparagine. In the cytosol, asparagine is degraded primarily via asparaginase and subsequent transamination. A new HPLC technique for separation of citric acid cycle intermediates was developed using: ion pairing with 20 mM each to tetrabutylammonium hydroxide and Na/sub 2/SO/sub 4/; pH 7.0; isocratic elution; and detection at 210 nm. Amino acid content of mouse lymphoma cells either sensitive (L5178Y) or resistant (L5178Y/L-ASE) to the anticancer drug L-asparaginase was studied. The concentration of asparagine was 1.5 times higher and the concentrations of the essential amino acids histidine, methionine, valine and phenylalanine were two times higher in asparaginase-resistant than sensitive cells. In vivo but not in vitro studies indicated that glucine decreases in sensitive but not resistant cells upon asparaginase treatment. Asparagine and glycine metabolism was further studied using /sup 14/C radiolabel conversion of asparagine, glyoxylate, glycine and serine. Glycine metabolism is especially important in lymphomas and leukemias because these cells contain higher concentrations of glycine that other cancer and normal cells. Therefore, glycine levels were studied and were found to decrease in sensitive but not resistant cells upon asparaginase administration.

  20. Alanine flux in obese and healthy humans as evaluated by 15N- and 2H3-labeled alanines

    International Nuclear Information System (INIS)

    Hoffer, L.J.; Yang, R.D.; Matthews, D.E.; Bistrian, B.R.; Bier, D.M.; Young, V.R.

    1988-01-01

    Estimates of plasma alanine flux as measured in humans using L-[ 15 N]-alanine or L-[3,3,3- 2 H 3 ]alanine were compared by simultaneous intravenous infusion of both tracers. Plasma isotope enrichments were measured by chemical ionization gas chromatography-mass spectrometry. In 16 obese women before and during a hypocaloric diet and in 4 normal men in the postabsorptive and fed states, the fluxes were highly correlated (r2 = 0.93) although plasma alanine flux with the 2 H tracer was two to three times greater than that obtained with [ 15 N]alanine. The fluxes decreased with the hypocaloric diet in obese subjects and increased during the fed state in healthy adults. Thus, although the estimates of alanine flux differed according to the tracer used, both appear to give equivalent information about changes in alanine kinetics induced by the nutritional conditions examined

  1. D-serine increases adult hippocampal neurogenesis

    Directory of Open Access Journals (Sweden)

    Sebastien eSultan

    2013-08-01

    Full Text Available Adult hippocampal neurogenesis results in the continuous formation of new neurons and is a process of brain plasticity involved in learning and memory. The neurogenic niche regulates the stem cell proliferation and the differentiation and survival of new neurons and a major contributor to the neurogenic niche are astrocytes. Among the molecules secreted by astrocytes, D-serine is an important gliotransmitter and is a co-agonist of the glutamate, N-methyl-D-aspartate (NMDA receptor. D-serine has been shown to enhance the proliferation of neural stem cells in vitro, but its effect on adult neurogenesis in vivo is unknown. Here, we tested the effect of exogenous administration of D-serine on adult neurogenesis in the mouse dentate gyrus. We found that 1 week of treatment with D-serine increased cell proliferation in vivo and in vitro and increased the density of neural stem cells and transit amplifying progenitors. Furthermore, D-serine increased the survival of newborn neurons. Together, these results indicate that D-serine treatment resulted in the improvement of several steps of adult neurogenesis in vivo.

  2. Formation of intercalation compound of kaolinite-glycine via displacing guest water by glycine.

    Science.gov (United States)

    Zheng, Wan; Zhou, Jing; Zhang, Zhenqian; Chen, Likun; Zhang, Zhongfei; Li, Yong; Ma, Ning; Du, Piyi

    2014-10-15

    The kaolinite-glycine intercalation compound was successfully formed by displacing intercalated guest water molecules in kaolinite hydrate as a precursor. The microstructure of the compound was characterized by X-ray diffraction, Fourier Transform Infrared Spectroscopy and Scanning Electron Microscope. Results show that glycine can only be intercalated into hydrated kaolinite to form glycine-kaolinite by utilizing water molecules as a transition phase. The intercalated glycine molecules were squeezed partially into the ditrigonal holes in the silicate layer, resulting in the interlayer distance of kaolinite reaching 1.03nm. The proper intercalation temperature range was between 20°C and 80°C. An intercalation time of 24h or above was necessary to ensure the complete formation of kaolinite-glycine. The highest intercalation degree of about 84% appeared when the system was reacted at the temperature of 80°C for 48h. There were two activation energies for the intercalation of glycine into kaolinite, one being 21kJ/mol within the temperature range of 20-65°C and the other 5.8kJ/mol between 65°C and 80°C. The intercalation degree (N) and intercalation velocity (v) of as a function of intercalation time (t) can be empirically expressed as N=-79.35e(-)(t)(/14.8)+80.1 and v=5.37e(-)(t)(/14.8), respectively. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Simultaneous determination of F-beta-alanine and beta-alanine in plasma and urine with dual-column reversed-phase high-performance liquid chromatography

    NARCIS (Netherlands)

    van Kuilenburg, A. B.; Stroomer, A. E.; Peters, G. J.; van Gennip, A. H.

    2001-01-01

    F-beta-Alanine and beta-alanine were detected in plasma and urine samples with fluorescence detection of orthophthaldialdehyde derivatives of F-beta-alanine and beta-alanine after separation with dual-column reversed-phase HPLC. The detection limits of F-beta-alanine and beta-alanine in the HPLC

  4. Utilization of exogenous ethanol by pea seedlings in an oxygen-free environment

    International Nuclear Information System (INIS)

    Ivanov, B.F.; Zemlyanukhin, A.A.; Salam, A.M.M.

    1991-01-01

    The authors investigated the metabolism of exogenous [2- 14 C]-ethanol in pea seedlings (Pisum sativum L.) exposed to different gaseous media, viz.,air, helium, or CO 2 . The 14 C label from ethanol most actively entered amino acids (glutamic and aspartic acids, alanine, glycine, and serine) and organic acids (citrate, malate, succinate, and malonate). Conversion of ethanol to organic acids and separate amino acids (gamma-aminobutyric acid and valine) was intensified under conditions of oxygen stress. A high concentration of CO 2 stimulated transformations of ethanol into these two amino acids, but sharply inhibited overall entry of the label from exogenous ethanol into metabolites of the seedlings. Lengthening the time of exposure lowered this inhibition. Exogenous ethanol did not take part in stress accumulation of alanine in seedlings deprived of oxygen. It is concluded that ethanol participates actively in the metabolic response of pea plants to oxygen stress, and that CO 2 exerts strong modifying action on this response

  5. Concentration and characterization of dissolved organic matter in the surface microlayer and subsurface water of the Bohai Sea, China

    Science.gov (United States)

    Chen, Yan; Yang, Gui-Peng; Wu, Guan-Wei; Gao, Xian-Chi; Xia, Qing-Yan

    2013-01-01

    A total of 19 sea-surface microlayer and corresponding subsurface samples collected from the Bohai Sea, China in April 2010 were analyzed for chlorophyll a, dissolved organic carbon (DOC) and its major compound classes including total dissolved carbohydrates (TDCHO, including monosaccharides, MCHO, and polysaccharides, PCHO) and total hydrolysable amino acids (THAA, including dissolved free, DFAA, and combined fraction, DCAA). The concentrations of DOC in the subsurface water ranged from 130.2 to 407.7 μM C, with an average of 225.9±75.4 μM C, while those in the surface microlayer varied between 140.1 and 330.9 μM C, with an average of 217.8±56.8 μM C. The concentrations of chlorophyll a, DOC, TDCHO and THAA in the microlayer were, respectively correlated with their subsurface water concentrations, implying that there was a strong exchange effect between the microlayer and subsurface water. The concentrations of DOC and TDCHO were negatively correlated with salinity, respectively, indicating that water mixing might play an important role in controlling the distribution of DOC and TDCHO in the water column. Major constituents of DCAA and DFAA present in the study area were glycine, alanine, glutamic acid, serine and histidine. Principal component analysis (PCA) was applied to examine the complex compositional differences that existed among the sampling sites. Our results showed that DFAA had higher mole percentages of glycine, valine and serine in the microlayer than in the subsurface water, while DCAA tended to have higher mole percentages of glutamic acid, aspartic acid, threonine, arginine, alanine, tyrosine, phenylalanine and leucine in the microlayer. The yields of TDCHO and THAA exhibited similar trends between the microlayer and subsurface water. Carbohydrate species displayed significant enrichment in the microlayer, whereas the DFAA and DCAA exhibited non-uniform enrichment in the microlayer.

  6. Molecular sites for the positive allosteric modulation of glycine receptors by endocannabinoids.

    Directory of Open Access Journals (Sweden)

    Gonzalo E Yévenes

    Full Text Available Glycine receptors (GlyRs are transmitter-gated anion channels of the Cys-loop superfamily which mediate synaptic inhibition at spinal and selected supraspinal sites. Although they serve pivotal functions in motor control and sensory processing, they have yet to be exploited as drug targets partly because of hitherto limited possibilities for allosteric control. Endocannabinoids (ECs have recently been characterized as direct allosteric GlyR modulators, but the underlying molecular sites have remained unknown. Here, we show that chemically neutral ECs (e.g. anandamide, AEA are positive modulators of α(1, α(2 and α(3 GlyRs, whereas acidic ECs (e.g. N-arachidonoyl-glycine; NA-Gly potentiate α(1 GlyRs but inhibit α(2 and α(3. This subunit-specificity allowed us to identify the underlying molecular sites through analysis of chimeric and mutant receptors. We found that alanine 52 in extracellular loop 2, glycine 254 in transmembrane (TM region 2 and intracellular lysine 385 determine the positive modulation of α(1 GlyRs by NA-Gly. Successive substitution of non-conserved extracellular and TM residues in α(2 converted NA-Gly-mediated inhibition into potentiation. Conversely, mutation of the conserved lysine within the intracellular loop between TM3 and TM4 attenuated NA-Gly-mediated potentiation of α(1 GlyRs, without affecting inhibition of α(2 and α(3. Notably, this mutation reduced modulation by AEA of all three GlyRs. These results define molecular sites for allosteric control of GlyRs by ECs and reveal an unrecognized function for the TM3-4 intracellular loop in the allosteric modulation of Cys-loop ion channels. The identification of these sites may help to understand the physiological role of this modulation and facilitate the development of novel therapeutic approaches to diseases such as spasticity, startle disease and possibly chronic pain.

  7. Development and validation of a rapid, selective, and sensitive LC-MS/MS method for simultaneous determination of D- and L-amino acids in human serum: application to the study of hepatocellular carcinoma.

    Science.gov (United States)

    Han, Minlu; Xie, Mengyu; Han, Jun; Yuan, Daoyi; Yang, Tian; Xie, Ying

    2018-04-01

    A validated liquid chromatography-tandem mass spectrometry method was developed for the simultaneous determination of D- and L-amino acids in human serum. Under the optimum conditions, except for DL-proline, L-glutamine, and D-lysine, the enantioseparation of the other 19 enantiomeric pairs of proteinogenic amino acids and nonchiral glycine was achieved with a CROWNPAK CR-I(+) chiral column within 13 min. The lower limits of quantitation for L-amino acids (including glycine) and D-amino acids were 5-56.25 μM and 0.625-500 nM, respectively, in human serum. The intraday precision and interday precision for all the analytes were less than 15%, and the accuracy ranged from -12.84% to 12.37% at three quality control levels. The proposed method, exhibiting high rapidity, enantioresolution, and sensitivity, was successfully applied to the quantification of D- and L-amino acid levels in serum from hepatocellular carcinoma patients and healthy individuals. The serum concentrations of L-arginine, L-isoleucine, L-aspartate, L-tryptophan, L-alanine, L-methionine, L-serine, glycine, L-valine, L-leucine, L-phenylalanine, L-threonine, D-isoleucine, D-alanine, D-glutamate, D-glutamine, D-methionine, and D-threonine were significantly reduced in the hepatocellular carcinoma patients compared with the healthy individuals (P hepatocellular carcinoma research. Graphical abstract Simultaneous determination of D- and L-amino acids in human serum from hepatocellular carcinoma patients and healthy individuals. AA amino acid, HCC hepatocellular carcinoma, LC liquid chromatography, MS/MS tandem mass spectrometry, NC normal control, TIC total ion chromatogram.

  8. Water-resistant alanine-EPR dosimeter alanpol

    International Nuclear Information System (INIS)

    Peimel-Stuglik, Zofia; Bryl-Sandelewska, Teresa; Mirkowski, Krzysztof; Sartowska, Bozena

    2009-01-01

    Alanpol-water-resistant alanine-electron paramagnetic resonance (EPR) dosimeter consisted of cheap DL-α-alanine (9.8-27%) suspended in polyethylene matrix was presented. The rods (O=2.8 mm) were extruded from a hot mixture of alanine and low-density polyethylene. No grinding or crushing was used for alanine preparation. An orientation of cylindrical crystals, up to 300 μm long in parallel to the rod axis was responsible for some differences in a shape of EPR signal. These differences had no negative consequences for dosimetric applications. Signal-to-dose dependence was linear up to 10 kGy. Standard deviation of dosimetric answer was up to ±1.8% and up to 2.4% for dosimeters with 9.8% and 27% of DL-α-alanine, respectively. Irradiation temperature coefficient for both dosimeters was equal 0.2%/ deg. C. Hydrophobic properties of polyethylene and small number of alanine crystals located on the surface of the rod led to high resistance of dosimeters to water and humidity. The 24 h soaking of irradiated dosimeters in liquid water-reduced EPR signals by 3-4% and by 2-3% for dosimeters with 27% and 9.8% of DL-α-alanine, respectively. Three month storage time of irradiated dosimeters in room conditions decreases EPR signal for ∼3%.

  9. Alanine-polymer dosemeter of ionizing radiation

    International Nuclear Information System (INIS)

    Tomasinski, Z.; Mirkowski, K.; Panta, P.; Stachowicz, W.

    1994-01-01

    The method of chemical preparation of alanine-copolymer of ethylene and vinyl acetate has been worked out. The material has been in a form of rods. The content of alanine has not exceeded 30%. The ESR signal of alanine radicals has been detected after exposition to ionizing radiation. The dose-response relationship has been presented

  10. Alanine transaminase (ALT) blood test

    Science.gov (United States)

    ... gov/ency/article/003473.htm Alanine transaminase (ALT) blood test To use the sharing features on this page, please enable JavaScript. The alanine transaminase (ALT) blood test measures the level of the enzyme ALT in ...

  11. Draft genome sequence of Micrococcus luteus strain O'Kane implicates metabolic versatility and the potential to degrade polyhydroxybutyrates

    Directory of Open Access Journals (Sweden)

    Radwa A. Hanafy

    2016-09-01

    Full Text Available Micrococcus luteus is a predominant member of skin microbiome. We here report on the genomic analysis of Micrococcus luteus strain O'Kane that was isolated from an elevator. The partial genome assembly of Micrococcus luteus strain O'Kane is 2.5 Mb with 2256 protein-coding genes and 62 RNA genes. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of glucose, galactose, fructose, mannose, alanine, aspartate, asparagine, glutamate, glutamine, glycine, serine, cysteine, methionine, arginine, proline, histidine, phenylalanine, and fatty acids. Genomic comparison to other M. luteus representatives identified the potential to degrade polyhydroxybutyrates, as well as several antibiotic resistance genes absent from other genomes.

  12. Effect of amino acids on red pigments and citrinin production in Monascus ruber.

    Science.gov (United States)

    Hajjaj, Hassan; François, Jean-Marie; Goma, Gérard; Blanc, Philippe J

    2012-03-01

    Amino acids were used as sole nitrogen sources to examine their effects on the production of water-soluble red pigments and citrinin by Monascus ruber ATCC 96218 cultivated on chemically defined media. In general, when glycine, tyrosine, arginine, serine, or histidine were used as sole nitrogen sources, they favored the production of red pigments, and restricted the synthesis of the mycotoxin. In contrast, the production of citrinin was enhanced in media supplemented with either glutamate, alanine, or proline. Histidine was found to be the most valuable amino acid as it resulted in the highest production of red pigments and almost completely eliminated the formation of mycotoxin. © 2012 Institute of Food Technologists®

  13. Draft genome sequence of Microbacterium oleivorans strain Wellendorf implicates heterotrophic versatility and bioremediation potential

    Directory of Open Access Journals (Sweden)

    Anton P. Avramov

    2016-12-01

    Full Text Available Microbacterium oleivorans is a predominant member of hydrocarbon-contaminated environments. We here report on the genomic analysis of M. oleivorans strain Wellendorf that was isolated from an indoor door handle. The partial genome of M. oleivorans strain Wellendorf consists of 2,916,870 bp of DNA with 2831 protein-coding genes and 49 RNA genes. The organism appears to be a versatile mesophilic heterotroph potentially capable of hydrolysis a suite of carbohydrates and amino acids. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of glucose, fructose, rhamnose, galactose, xylose, arabinose, alanine, aspartate, asparagine, glutamate, serine, glycine, threonine and cysteine. This is the first detailed analysis of a Microbacterium oleivorans genome.

  14. Pressure-induced phase transitions in organic molecular crystals: a combination of x-ray single-crystal and powder diffraction, raman and IR-spectroscopy

    International Nuclear Information System (INIS)

    Boldyreva, E V; Goryainov, S V; Seryotkin, Y V; Kolesnik, E N; Shakhtshneider, T P; Ivashevskaya, S N; Drebushchak, T N; Sowa, H; Ahsbahs, H; Chernyshev, V V; Dmitriev, V P

    2008-01-01

    The contribution summarizes the results of recent studies of phase transitions induced by high pressure in a number of molecular organic crystals, such as polymorphs of paracetamol, chlorpropamide, polymorphs of glycine, L- and DL-serine, β-alanine. The main attention is paid to the following topics: (1) Reversible / irreversible transformations; (2) Different behavior of single crystals / powders; (3) The role of pressure-transmitting liquid; (4) The role of the kinetic factors: phase transitions on decompression, or after a long storage at a selected pressure; (5) Isosymmetric phase transitions; (6) The role of the changes in the hydrogen bond networks / intramolecular conformational changes in the phase transitions; (7) Superstructures / nanostructures formed as a result of pressure-induced phase transitions

  15. Pressure-induced phase transitions in organic molecular crystals: a combination of x-ray single-crystal and powder diffraction, raman and IR-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Boldyreva, E V; Goryainov, S V; Seryotkin, Y V; Kolesnik, E N; Shakhtshneider, T P; Ivashevskaya, S N; Drebushchak, T N [Research and Education Center ' Molecular Design and Ecologically Safe Technologies' , REC-008, Novosibirsk State University (Russian Federation); Sowa, H [Goettingen University (Germany); Ahsbahs, H; Chernyshev, V V [Marburg University (Germany); Dmitriev, V P [Swiss-Norwegian Beamline ESRF, Grenoble (France)], E-mail: boldyrev@nsu.ru

    2008-07-15

    The contribution summarizes the results of recent studies of phase transitions induced by high pressure in a number of molecular organic crystals, such as polymorphs of paracetamol, chlorpropamide, polymorphs of glycine, L- and DL-serine, {beta}-alanine. The main attention is paid to the following topics: (1) Reversible / irreversible transformations; (2) Different behavior of single crystals / powders; (3) The role of pressure-transmitting liquid; (4) The role of the kinetic factors: phase transitions on decompression, or after a long storage at a selected pressure; (5) Isosymmetric phase transitions; (6) The role of the changes in the hydrogen bond networks / intramolecular conformational changes in the phase transitions; (7) Superstructures / nanostructures formed as a result of pressure-induced phase transitions.

  16. Alanine metabolism in pyridoxine-depleted rat liver

    International Nuclear Information System (INIS)

    Okada, Mitsuko; Abe, Midori

    1976-01-01

    Alanine metabolism in normal and pyridoxine-deficient rats was studied in vivo and in vitro. Incorporation of 14 C-alanine into various liver components was determined and no difference was shown between normal and deficient animals in the incorporation into liver homogenates, lipid, protein and plasma glucose. Using the liver slice system, gluconeogenic activity from alanine or pyruvate was 40% lower in deficient rats compared with the activity of normal rats. However, inhibition was completely removed by the addition of 2-oxoglutarate to alanine. Penicillamine did not affect glucose formation from alanine in the liver slice. (auth.)

  17. 76 FR 8771 - Glycine From China

    Science.gov (United States)

    2011-02-15

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-718 (Third Review)] Glycine From China... order on glycine from China. SUMMARY: The Commission hereby gives notice that it will proceed with a... determine whether revocation of the antidumping duty order on glycine from China would be likely to lead to...

  18. 76 FR 55109 - Glycine From China

    Science.gov (United States)

    2011-09-06

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-718 (Third Review)] Glycine From China... U.S.C. 1675(c)), that revocation of the antidumping duty order on glycine from China would be likely... contained in USITC Publication 4255 (August 2011), entitled Glycine from China: Investigation No. 731-TA-718...

  19. Liver peroxisomal alanine:glyoxylate aminotransferase and the effects of mutations associated with Primary Hyperoxaluria Type I: An overview.

    Science.gov (United States)

    Oppici, Elisa; Montioli, Riccardo; Cellini, Barbara

    2015-09-01

    Liver peroxisomal alanine:glyoxylate aminotransferase (AGT) (EC 2.6.1.44) catalyses the conversion of l-alanine and glyoxylate to pyruvate and glycine, a reaction that allows glyoxylate detoxification. Inherited mutations on the AGXT gene encoding AGT lead to Primary Hyperoxaluria Type I (PH1), a rare disorder characterized by the deposition of calcium oxalate crystals primarily in the urinary tract. Here we describe the results obtained on the biochemical features of AGT as well as on the molecular and cellular effects of polymorphic and pathogenic mutations. A complex scenario on the molecular pathogenesis of PH1 emerges in which the co-inheritance of polymorphic changes and the condition of homozygosis or compound heterozygosis are two important factors that determine the enzymatic phenotype of PH1 patients. All the reported data represent relevant steps toward the understanding of genotype/phenotype correlations, the prediction of the response of the patients to the available therapies, and the development of new therapeutic approaches. This article is part of a Special Issue entitled: Cofactor-dependent proteins: evolution, chemical diversity and bio-applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Optimised formation of blue Maillard reaction products of xylose and glycine model systems and associated antioxidant activity.

    Science.gov (United States)

    Yin, Zi; Sun, Qian; Zhang, Xi; Jing, Hao

    2014-05-01

    A blue colour can be formed in the xylose (Xyl) and glycine (Gly) Maillard reaction (MR) model system. However, there are fewer studies on the reaction conditions for the blue Maillard reaction products (MRPs). The objective of this study is to investigate characteristic colour formation and antioxidant activities in four different MR model systems and to determine the optimum reaction conditions for the blue colour formation in a Xyl-Gly MR model system, using the random centroid optimisation program. The blue colour with an absorbance peak at 630 nm appeared before browning in the Xyl-Gly MR model system, while no blue colour formation but only browning was observed in the xylose-alanine, xylose-aspartic acid and glucose-glycine MR model systems. The Xyl-Gly MR model system also showed higher antioxidant activity than the other three model systems. The optimum conditions for blue colour formation were as follows: xylose and glycine ratio 1:0.16 (M:M), 0.20 mol L⁻¹ NaHCO₃, 406.1 mL L⁻¹ ethanol, initial pH 8.63, 33.7°C for 22.06 h, which gave a much brighter blue colour and a higher peak at 630 nm. A characteristic blue colour could be formed in the Xyl-Gly MR model system and the optimum conditions for the blue colour formation were proposed and confirmed. © 2013 Society of Chemical Industry.

  1. Utilization of [1-14C]carbon of glycine of high glycine diet fed young and old rats

    International Nuclear Information System (INIS)

    Petzke, K.J.; Albrecht, V.; Medovar, B.Ya.; Pisarczuk, K.L.; Grigorov, Yu.G.

    1987-01-01

    The incorporation of radioactivity from [1- 14 C]glycine was studied in various organ (serum, liver, muscle) fractions (acid soluble, proteins, lipids, liver glycogen) and carbon dioxide in rats fed with isonitrogenous isocaloric purfied diets. The diets contained 30% casein (control), gelatin (exchange of half of the 30% casein) or glycine (corresponding level of glycine in relation to the gelatin diet). The incorporation of radioactivity into proteins was reduced by feeding high glycine diets in young (20-weeks-old) and old (18-month-old) rats in relation to the control diet. The modifications of the results for old animals may be partially explained on the base of a reduced protein turnover rate and adaptation to a high gelatin (glycine) diet. (author)

  2. Protection against hyperthermic cell killing by alanine

    International Nuclear Information System (INIS)

    Cunningham, A.; Henle, K.J.; Moss, A.J.; Nagle, W.A.

    1987-01-01

    Compounds capable of protecting cells against hyperthermia may provide new insights into potential mechanisms of thermotolerance and cellular heat death. The authors characterized heat protection by alanine and related compounds as a function of concentration, temperature and preincubation time. Alanine was added either to complete medium or to HBSS before hyperthermia. Maximal heat protection required 3 hr, 37 0 ; longer preincubation intervals resulted in lower levels of protection. Addition of alanine to medium after hyperthermia had no protective effect. Protection was concentration dependent with a 20- or 200-fold increase in cell survival after 40 min, 45 0 C at 60 mM in medium or in HBSS, respectively. Higher alanine concentrations up to 120mM did not significantly increase heat protection. A 45 0 -heat survival curve showed that 100mM alanine increased the D/sub q/ by approx. 12 min with little change in the D/sub o/. Hyperthermia of 1 hr at temperatures between 42 0 and 45 0 indicated that 100mM alanine shifted the isotoxic temperature by 0.5 Celsius degrees. Polymers of either L or D,L alanine and related compounds, like pyruvate, also protected cells against heat killing. These results indicate that heat protection by alanine shows characteristics that are not shared by polyhydroxy compounds

  3. Utilization of 15N-labelled urea in laying hens. 8

    International Nuclear Information System (INIS)

    Gruhn, K.; Graf, H.

    1987-01-01

    3 colostomized laying hybrids received orally with a conventional ration 1% urea with 96.06 atom-% 15 N excess ( 15 N') over a period of 6 days. In the period of the experiment every hen consumed 2.87 g 15 N'. After another 2 days, on which they received conventional feed urea, the animals were butchered. 15 N' was determined in the total N and in 15 amino acids of the oviduct. Of the 15 amino acids the labelling of glutamic acid, glycine and serine was highest and on average amounted to 0.80, 0.66 and 0.67 atom-% 15 N', resp. In lysine and arginine only 0.10 and 0.11 atom-% 15 N' could be detected. The amino acid N with natural isotopic frequency amounted to a quarter for the basic amino acids, a tenth for the branched chain ones and for the non-essential ones (glutamic acid, aspartic acid, serine, glycine, alanine, proline) a third of the total oviduct 14 N. The average quota of 15 N' is only 3.6%, that of the branched chain amino acids 4.5 and that of the non-essential ones 21.1%. Consequently, the 15 N' of the urea is mainly used for the synthesis of the non-essential amino acids of the oviduct. (author)

  4. Molecular basis of adult-onset and chronic G sub M2 gangliosidoses in patients of Ashkenazi Jewish origin: Substitution of serine for glycine at position 269 of the. alpha. -subunit of. beta. -hexosaminidase

    Energy Technology Data Exchange (ETDEWEB)

    Paw, B.H.; Kaback, M.M.; Neufeld, E.F. (Univ. of California, Los Angeles (USA))

    1989-04-01

    Chronic and adult-onset G{sub M2} gangliosidoses are neurological disorders caused by marked deficiency of the A isoenzyme of {beta}-hexosaminidase; they occur in the Ashkenazi Jewish population, though less frequently than classic (infantile) Tay-Sachs disease. Earlier biosynthetic studies had identified a defective {alpha}-subunit that failed to associate with the {beta}-subunit. The authors have now found a guanosine to adenosine transition at the 3{prime} end of exon 7, which causes substitution of serine for glycine at position 269 of the {alpha}-subunit. An RNase protection assay was used to localize the mutation to a segment of mRNA from fibroblasts of a patient with the adult-onset disorder. That segment of mRNA (after reverse transcription) and a corresponding segment of genomic DNA were amplified by the polymerase chain reaction and sequenced by the dideoxy method. The sequence analysis, together with an assay based on the loss of a ScrFI restriction site, showed that the patient was a compound heterozygote who had inherited the 269 (Gly {yields} Ser) mutation from his father and an allelic null mutation from his mother. The 269 (Gly {yields} Ser) mutation, in compound heterozygosity with a presumed null allele, was also found in fetal fibroblasts with an association-defective phenotype and in cells from five patients with chronic G{sub M2} gangliosidosis.

  5. Urine metabolomics in rats after administration of ketamine

    Directory of Open Access Journals (Sweden)

    Wen C

    2015-02-01

    Full Text Available Congcong Wen,1 Meiling Zhang,2 Jianshe Ma,2 Lufeng Hu,3 Xianqin Wang,2 Guanyang Lin31Laboratory Animal Centre, 2Analytical and Testing Center, 3First Affiliated Hospital of Wenzhou Medical University, Wenzhou, People’s Republic of ChinaAbstract: In this study, we developed a urine metabonomic method, based on gas chromatography–mass spectrometry (GC-MS, to evaluate the effect of ketamine on rats. Pattern recognition analysis, including both principal component analysis and partial least squares discriminate analysis revealed that ketamine (50 mg/kg induced metabolic perturbations. Compared with the control group, at day 7, the level of alanine, butanoic acid, glutamine, butanedioic, trimethylsiloxy, L-aspartic acid, D-glucose, cholesterol, acetamide, and oleic acid of the ketamine group was increased, while the level of 2,3,4-trihydroxybutyric acid, benzene­acetic acid, threitol, ribitol, xylitol, and glycine decreased. At day 14, the level of alanine, ethanedioic acid, L-proline, glycerol, tetradecanoic acid, l-serine, l-phenylalanine, L-aspartic acid, d-glucose, cholesterol, heptadecanoic acid, and acetamide in rat urine of the ketamine group was increased, while the 2,3,4-trihydroxybutyric acid, benzeneacetic acid, d-ribose, threitol, ribitol, glycine, pyrazine, and oleic acid levels decreased. Our results indicate that metabonomic methods based on GC-MS may be useful to elucidate ketamine abuse, through the exploration of biomarkers.Keywords: GC-MS, abuse, biomarker, metabolite

  6. Isotopic effects in mechanistic studies of biotransformations of fluorine derivatives of L-alanine catalysed by L-alanine dehydrogenase

    International Nuclear Information System (INIS)

    Szymańska-Majchrzak, Jolanta; Pałka, Katarzyna; Kańska, Marianna

    2017-01-01

    Synthesis of 3-fluoro-[2- 2 H]-L-alanine (3-F-[ 2 H]-L-Ala) in reductive amination of 3-fluoropyruvic acid catalysed by L-alanine dehydrogenase (AlaDH) was described. Fluorine derivative was used to study oxidative deamination catalysed by AlaDH applied kinetic (for 3-F-L-Ala in H 2 O - KIE’s on V max : 1.1; on V max /K M : 1.2; for 3-F-L-Ala in 2 H 2 O – on V max : 1.4; on V max /K M : 2.1) and solvent isotope effect methods (for 3-F-L-Ala - SIE’s on V max : 1.0; on V max /K M : 0.87; for 3-F-[2- 2 H]-L-Ala – on V max : 1.4; on V max /K M : 1.5). Studies explain some details of reaction mechanism. - Highlights: • Synthesis of 3-fluoro-[2- 2 H]-L-alanine was performed. • The reactions were catalysed using the enzyme L-alanine dehydrogenase. • Performed reactions involved fluorinated analogues of L-alanine. • Solvent isotope effects of deuterium were determined. • Kinetic isotope effects were determined for obtained 3-fluoro-L-alanine. • The mechanism of reaction catalysed by L-alanine dehydrogenase was proposed.

  7. Sphingoid bases and the serine catabolic enzyme CHA1 define a novel feedforward/feedback mechanism in the response to serine availability.

    Science.gov (United States)

    Montefusco, David J; Newcomb, Benjamin; Gandy, Jason L; Brice, Sarah E; Matmati, Nabil; Cowart, L Ashley; Hannun, Yusuf A

    2012-03-16

    Targets of bioactive sphingolipids in Saccharomyces cerevisiae were previously identified using microarray experiments focused on sphingolipid-dependent responses to heat stress. One of these heat-induced genes is the serine deamidase/dehydratase Cha1 known to be regulated by increased serine availability. This study investigated the hypothesis that sphingolipids may mediate the induction of Cha1 in response to serine availability. The results showed that inhibition of de novo synthesis of sphingolipids, pharmacologically or genetically, prevented the induction of Cha1 in response to increased serine availability. Additional studies implicated the sphingoid bases phytosphingosine and dihydrosphingosine as the likely mediators of Cha1 up-regulation. The yeast protein kinases Pkh1 and Pkh2, known sphingoid base effectors, were found to mediate CHA1 up-regulation via the transcription factor Cha4. Because the results disclosed a role for sphingolipids in negative feedback regulation of serine metabolism, we investigated the effects of disrupting this mechanism on sphingolipid levels and on cell growth. Intriguingly, exposure of the cha1Δ strain to high serine resulted in hyperaccumulation of endogenous serine and in turn a significant accumulation of sphingoid bases and ceramides. Under these conditions, the cha1Δ strain displayed a significant growth defect that was sphingolipid-dependent. Together, this work reveals a feedforward/feedback loop whereby the sphingoid bases serve as sensors of serine availability and mediate up-regulation of Cha1 in response to serine availability, which in turn regulates sphingolipid levels by limiting serine accumulation.

  8. Crystallization and preliminary crystallographic analysis of d-alanine-d-alanine ligase from Streptococcus mutans

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yong-Zhi; Sheng, Yu [Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China); Li, Lan-Fen [National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871 (China); Tang, De-Wei [Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China); Liu, Xiang-Yu [National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871 (China); Zhao, Xiaojun, E-mail: zhaoxj@scu.edu.cn [Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China); Liang, Yu-He, E-mail: zhaoxj@scu.edu.cn; Su, Xiao-Dong [National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871 (China); Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China)

    2007-09-01

    A potential target for antibiotic drug design, d-alanine-d-alanine ligase from S. mutans, was expressed in E. coli, purified and crystallized. Diffraction data were collected to 2.4 Å resolution. d-Alanine-d-alanine ligase is encoded by the gene ddl (SMU-599) in Streptococcus mutans. This ligase plays a very important role in cell-wall biosynthesis and may be a potential target for drug design. To study the structure and function of this ligase, the gene ddl was amplified from S. mutans genomic DNA and cloned into the expression vector pET28a. The protein was expressed in soluble form in Escherichia coli strain BL21 (DE3). Homogeneous protein was obtained using a two-step procedure consisting of Ni{sup 2+}-chelating and size-exclusion chromatography. Purified protein was crystallized and the cube-shaped crystal diffracted to 2.4 Å. The crystal belongs to space group P3{sub 1}21 or P3{sub 2}21, with unit-cell parameters a = b = 79.50, c = 108.97 Å. There is one molecule per asymmetric unit.

  9. Crystallization and preliminary crystallographic analysis of d-alanine-d-alanine ligase from Streptococcus mutans

    International Nuclear Information System (INIS)

    Lu, Yong-Zhi; Sheng, Yu; Li, Lan-Fen; Tang, De-Wei; Liu, Xiang-Yu; Zhao, Xiaojun; Liang, Yu-He; Su, Xiao-Dong

    2007-01-01

    A potential target for antibiotic drug design, d-alanine-d-alanine ligase from S. mutans, was expressed in E. coli, purified and crystallized. Diffraction data were collected to 2.4 Å resolution. d-Alanine-d-alanine ligase is encoded by the gene ddl (SMU-599) in Streptococcus mutans. This ligase plays a very important role in cell-wall biosynthesis and may be a potential target for drug design. To study the structure and function of this ligase, the gene ddl was amplified from S. mutans genomic DNA and cloned into the expression vector pET28a. The protein was expressed in soluble form in Escherichia coli strain BL21 (DE3). Homogeneous protein was obtained using a two-step procedure consisting of Ni 2+ -chelating and size-exclusion chromatography. Purified protein was crystallized and the cube-shaped crystal diffracted to 2.4 Å. The crystal belongs to space group P3 1 21 or P3 2 21, with unit-cell parameters a = b = 79.50, c = 108.97 Å. There is one molecule per asymmetric unit

  10. Understanding serine proteases implications on Leishmania spp lifecycle.

    Science.gov (United States)

    Alves, Carlos Roberto; Souza, Raquel Santos de; Charret, Karen Dos Santos; Côrtes, Luzia Monteiro de Castro; Sá-Silva, Matheus Pereira de; Barral-Veloso, Laura; Oliveira, Luiz Filipe Gonçalves; da Silva, Franklin Souza

    2018-01-01

    Serine proteases have significant functions over a broad range of relevant biological processes to the Leishmania spp lifecycle. Data gathered here present an update on the Leishmania spp serine proteases and the status of these enzymes as part of the parasite degradome. The serine protease genes (n = 26 to 28) in Leishmania spp, which encode proteins with a wide range of molecular masses (35 kDa-115 kDa), are described along with their degrees of chromosomal and allelic synteny. Amid 17 putative Leishmania spp serine proteases, only ∼18% were experimentally demonstrated, as: signal peptidases that remove the signal peptide from secretory pre-proteins, maturases of other proteins and with metacaspase-like activity. These enzymes include those of clans SB, SC and SF. Classical inhibitors of serine proteases are used as tools for the characterization and investigation of Leishmania spp. Endogenous serine protease inhibitors, which are ecotin-like, can act modulating host actions. However, crude or synthetic based-natural serine protease inhibitors, such as potato tuber extract, Stichodactyla helianthus protease inhibitor I, fukugetin and epoxy-α-lapachone act on parasitic serine proteases and are promising leishmanicidal agents. The functional interrelationship between serine proteases and other Leishmania spp proteins demonstrate essential functions of these enzymes in parasite physiology and therefore their value as targets for leishmaniasis treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Increased tolerance towards serine obtained by adaptive laboratory evolution

    DEFF Research Database (Denmark)

    Mundhada, Hemanshu; Seoane, Jose Miguel; Koza, Anna

    2014-01-01

    The amino acid serine has previously been identified as one of the top 30 candidates of value added chemicals, making the production of serine from glucose attractive. Production of serine have previously been attempted in E. coli and C. glutamicum, however, titers sufficient for commercial...... by glyA), the conversion of serine to pyruvate (encoded by sdaA, sdaB and tdcG) was also deleted. As expected, the resulting strain turned out to be susceptible to even low concentrations of serine in the media. In order to improve the tolerance of the strain towards serine, adaptive laboratory evolution....... During the evolution experiment, the serine tolerance was increased substantially. Genome re-sequencing was subsequently used to analyze the genotype of a number of selected strains. These results reveal insights towards the adaptation process as well as the mechanism of serine tolerance....

  12. Phosphorylations of Serines 21/9 in Glycogen Synthase Kinase 3α/β Are Not Required for Cell Lineage Commitment or WNT Signaling in the Normal Mouse Intestine.

    Directory of Open Access Journals (Sweden)

    Fiona Hey

    Full Text Available The WNT signalling pathway controls many developmental processes and plays a key role in maintenance of intestine renewal and homeostasis. Glycogen Synthase Kinase 3 (GSK3 is an important component of the WNT pathway and is involved in regulating β-catenin stability and expression of WNT target genes. The mechanisms underpinning GSK3 regulation in this context are not completely understood, with some evidence suggesting this occurs through inhibitory N-terminal serine phosphorylation in a similar way to GSK3 inactivation in insulin signaling. To investigate this in a physiologically relevant context, we have analysed the intestinal phenotype of GSK3 knockin mice in which N-terminal serines 21/9 of GSK3α/β have been mutated to non-phosphorylatable alanine residues. We show that these knockin mutations have very little effect on overall intestinal integrity, cell lineage commitment, β-catenin localization or WNT target gene expression although a small increase in apoptosis at villi tips is observed. Our results provide in vivo evidence that GSK3 is regulated through mechanisms independent of N-terminal serine phosphorylation in order for β-catenin to be stabilised.

  13. Antinociceptive Effect of Rat D-Serine Racemase Inhibitors, L-Serine-O-Sulfate, and L-Erythro-3-Hydroxyaspartate in an Arthritic Pain Model

    Directory of Open Access Journals (Sweden)

    Claudio Laurido

    2012-01-01

    Full Text Available N-methyl-D-aspartic acid receptor (NMDAr activation requires the presence of D-serine, synthesized from L-serine by a pyridoxal 5′-phosphate-dependent serine racemase (SR. D-serine levels can be lowered by inhibiting the racemization of L-serine. L-serine-O-sulfate (LSOS and L-erythro-3-hydroxyaspartate (LEHA, among others, have proven to be effective in reducing the D-serine levels in culture cells. It is tempting then to try these compounds in their effectiveness to decrease nociceptive levels in rat arthritic pain. We measured the C-reflex paradigm and wind-up potentiation in the presence of intrathecally injected LSOS (100 μg/10 μL and LEHA (100 μg/10 μL in normal and monoarthritic rats. Both compounds decreased the wind-up activity in normal and monoarthritic rats. Accordingly, all the antinociceptive effects were abolished when 300 μg/10 μL of D-serine were injected intrathecally. Since no in vivo results have been presented so far, this constitutes the first evidence that SR inhibitions lower the D-serine levels, thus decreasing the NMDAr activity and the consequent development and maintenance of chronic pain.

  14. Do glycine-extended hormone precursors have clinical significance?

    DEFF Research Database (Denmark)

    Rehfeld, Jens Frederik

    2014-01-01

    Half of the known peptide hormones are C-terminally amidated. Subsequent biogenesis studies have shown that the immediate precursor is a glycine-extended peptide. The clinical interest in glycine-extended hormones began in 1994, when it was suggested that glycine-extended gastrin stimulated cancer...... and clinical effects of glycine-extended precursors for most other amidated hormones than gastrin and cholecystokinin (CCK). The idea of glycine-extended peptides as independent messengers was interesting. But clinical science has to move ahead from ideas that cannot be supported at key points after decades...

  15. Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases; Part 1: alkyl halide alkylations.

    Science.gov (United States)

    Sorochinsky, Alexander E; Aceña, José Luis; Moriwaki, Hiroki; Sato, Tatsunori; Soloshonok, Vadim A

    2013-10-01

    Alkylations of chiral or achiral Ni(II) complexes of glycine Schiff bases constitute a landmark in the development of practical methodology for asymmetric synthesis of α-amino acids. Straightforward, easy preparation as well as high reactivity of these Ni(II) complexes render them ready available and inexpensive glycine equivalents for preparing a wide variety of α-amino acids, in particular on a relatively large scale. In the case of Ni(II) complexes containing benzylproline moiety as a chiral auxiliary, their alkylation proceeds with high thermodynamically controlled diastereoselectivity. Similar type of Ni(II) complexes derived from alanine can also be used for alkylation providing convenient access to quaternary, α,α-disubstituted α-amino acids. Achiral type of Ni(II) complexes can be prepared from picolinic acid or via recently developed modular approach using simple secondary or primary amines. These Ni(II) complexes can be easily mono/bis-alkylated under homogeneous or phase-transfer catalysis conditions. Origin of diastereo-/enantioselectivity in the alkylations reactions, aspects of practicality, generality and limitations of this methodology is critically discussed.

  16. Investigation of hydrolysis products in the acetone-butanol fermentation of vegetable agricultural waste materials

    Energy Technology Data Exchange (ETDEWEB)

    Nakhmanovich, B M

    1960-01-01

    Determinations of the fundamental chemical composition of corn stalk, sunflower husk, and hemp scutch by chromatography were reported, e.g. pentoses (1.98, 1.98, 2.01%), hexoses (1.59, 1.72, 2.01% respectively.) and various amino acids (arginine, asparagine, histidine, glutamine, glycine, lysine, proline, serine, tyrosine, threonine, cysteine, cystine, alanine, and aspartic and glutamic acids). The sterilized products from the hydrolysis (pentoses, hexoses) in a combined mixture with a meal mash were normally fermented at 37/sup 0/ in the presence of acetone-butanol bacteria for 40 to 48 hours, yielding 10.46 to 12.50% of acetone, 15.09 to 18.0% of butanol, 3.79 to 6.08% of ethanol (a total yielding being 30 to 42% of solvents).

  17. Experiences with alanine dosimetry in afterloading brachytherapy

    International Nuclear Information System (INIS)

    Eberhardt, H.-J.; Gohs, U.

    1996-01-01

    At the present, the most commonly used dosimetry for radiotherapy applications are ionisation chambers and thermoluminescent dosimeters (TLD). However, there are some undesirable characteristics of these dosimetry systems, such as large detection volume (ionisation chamber) as well as fading of the radiation induced signal with time and destructive readout (TLG). The present study is an investigation into the use of the alanine/ESR dosimetry in fractionated afterloading brachytherapy during the whole radiotherapy course. There are some qualities which make alanine dosimetry attractive. These are the linear energy response, low fading under standard conditions, and the nondestructive readout. Thus the alanine dosimetry makes possible cumulative dose measurements during the radiotherapy course and an archival storage. By ionizing radiation (gamma, e, n, p, charged particles) free radicals (unpaired electrons) are produced in the amino acid alanine. The continuous wave electron spin resonance (ESR) spectroscopy is used to determine the number of free radicals, which is proportional to the absorbed dose and the alanine content of the dosimeter. The ESR measurements were made at room temperature using a Bruker EPR analyzer EMS-104. The dosimeters used in the test are alanine pellets (23.72 mg weight, 4.9 mm diameter, 1 mm height) as well as flexible alanine film dosimeters (thickness about 500 μm). The dosimeters consist of a blend of L-alpha-alanine and a binder. The alanine content of the pellets and the film dosimeters is about 88 % and 50 % by weight, respectively. The dosimeters for the calculation of the dose-effect-relationship were irradiated at the Physical-Technical Bundesanstalt in Braunschweig by a standard 60Co source. The maximum deviation from the calculated linear function is about 0.12 Gy in the dose range up to 80 Gy. The goal of medical applications was the superficial dose measurement in afterloading brachytherapy during the radiotherapy course in

  18. Alanine increases blood pressure during hypotension

    Science.gov (United States)

    Conlay, L. A.; Maher, T. J.; Wurtman, R. J.

    1990-01-01

    The effect of L-alanine administration on blood pressure (BP) during haemorrhagic shock was investigated using anesthetized rats whose left carotid arteries were cannulated for BP measurement, blood removal, and drug administration. It was found that L-alanine, in doses of 10, 25, 50, 100, and 200 mg/kg, increased the systolic BP of hypotensive rats by 38 to 80 percent (while 100 mg/kg pyruvate increased BP by only 9.4 mmhg, not significantly different from saline). The results suggest that L-alanine might influence cardiovascular function.

  19. Expression, crystallization and preliminary X-ray crystallographic analysis of Xoo0352, d-alanine-d-alanine ligase A, from Xanthomonas oryzae pv. oryzae

    International Nuclear Information System (INIS)

    Doan, Thanh Thi Ngoc; Kim, Jin-Kwang; Kim, Hyesoon; Ahn, Yeh-Jin; Kim, Jeong-Gu; Lee, Byoung-Moo; Kang, Lin-Woo

    2008-01-01

    Xoo0352, which encodes d-alanine-d-alanine ligase A (DdlA), from X. oryzae pv. oryzae was cloned, purified and crystallized. Preliminary X-ray crystallographic analysis of DdlA crystals was performed. Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB), which is one of the most devastating diseases of rice in most rice-growing countries. d-Alanine-d-alanine ligase A (DdlA), coded by the Xoo0352 gene, was expressed, purified and crystallized. DdlA is an enzyme that is involved in d-alanine metabolism and the biosynthesis of an essential bacterial peptidoglycan precursor, in which it catalyzes the formation of d-alanyl-d-alanine from two d-alanines, and is thus an attractive antibacterial drug target against Xoo. The DdlA crystals diffracted to 2.3 Å resolution and belonged to the primitive tetragonal space group P4 3 2 1 2, with unit-cell parameters a = b = 83.0, c = 97.6 Å. There is one molecule in the asymmetric unit, with a corresponding V M of 1.88 Å 3 Da −1 and a solvent content of 34.6%. The initial structure was determined by molecular replacement using d-alanine-d-alanine ligase from Staphylococcus aureus as a template model

  20. Racemization of alanine by the alanine racemases from Salmonella typhimurium and Bacillus stearothermophilus: energetic reaction profiles

    International Nuclear Information System (INIS)

    Faraci, W.S.; Walsh, C.T.

    1988-01-01

    Alanine racemases are bacterial pyridoxal 5'-phosphate (PLP) dependent enzymes providing D-alanine as an essential building block for biosynthesis of the peptidoglycan layer of the cell wall. Two isozymic alanine racemases, encoded by the dadB gene and the alr gene, from the Gram-negative mesophilic Salmonella typhimurium and one from the Gram-positive thermophilic Bacillus stearothermophilus have been examined for the racemization mechanism. Substrate deuterium isotope effects and solvent deuterium isotope effects have been measured in both L → D and D→ L directions for all three enzymes to assess the degree to which abstraction of the α-proton or protonation of substrate PLP carbanion is limiting in catalysis. Additionally, experiments measuring internal return of α- 3 H from substrate to product and solvent exchange/substrate conversion experiments in 3 H 2 O have been used with each enzyme to examine the partitioning of substrate PLP carbanion intermediates and to obtain the relative heights of kinetically significant energy barriers in alanine racemase catalysis

  1. 21 CFR 520.550 - Dextrose/glycine/electrolyte.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dextrose/glycine/electrolyte. 520.550 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.550 Dextrose/glycine..., potassium citrate 0.12 gram, aminoacetic acid (glycine) 6.36 grams, and dextrose 44.0 grams. (b) Sponsor...

  2. Microbial Production of l-Serine from Renewable Feedstocks.

    Science.gov (United States)

    Zhang, Xiaomei; Xu, Guoqiang; Shi, Jinsong; Koffas, Mattheos A G; Xu, Zhenghong

    2018-07-01

    l-Serine is a non-essential amino acid that has wide and expanding applications in industry with a fast-growing market demand. Currently, extraction and enzymatic catalysis are the main processes for l-serine production. However, such approaches limit the industrial-scale applications of this important amino acid. Therefore, shifting to the direct fermentative production of l-serine from renewable feedstocks has attracted increasing attention. This review details the current status of microbial production of l-serine from renewable feedstocks. We also summarize the current trends in metabolic engineering strategies and techniques for the typical industrial organisms Corynebacterium glutamicum and Escherichia coli that have been developed to address and overcome major challenges in the l-serine production process. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Imaging analysis of direct alanine uptake by rice seedlings

    International Nuclear Information System (INIS)

    Nihei, Naoto; Masuda, Sayaka; Rai, Hiroki; Nakanishi, Tomoko M.

    2008-01-01

    We presented alanine, a kind of amino acids, uptake by a rice seedling to study the basic mechanism of the organic fertilizer effectiveness in organic farming. The rice grown in the culture solution containing alanine as a nitrogen source absorbed alanine approximately two times faster than that grown with NH 4 + from analysis of 14 C-alanine images by Imaging Plate method. It was suggested that the active transport ability of the rice seeding was induced in roots by existence of alanine in the rhizosphere. The alanine uptake images of the rice roots were acquired every 5 minutes successively by the real-time autoradiography system we developed. The analysis of the successive images showed that alanine uptake was not uniform throughout the root but especially active at the root tip. (author)

  4. Novel Serine 176 Phosphorylation of YBX1 Activates NF-κB in Colon Cancer.

    Science.gov (United States)

    Martin, Matthew; Hua, Laiqing; Wang, Benlian; Wei, Han; Prabhu, Lakshmi; Hartley, Antja-Voy; Jiang, Guanglong; Liu, Yunlong; Lu, Tao

    2017-02-24

    Y box protein 1 (YBX1) is a well known oncoprotein that has tumor-promoting functions. YBX1 is widely considered to be an attractive therapeutic target in cancer. To develop novel therapeutics to target YBX1, it is of great importance to understand how YBX1 is finely regulated in cancer. Previously, we have shown that YBX1 could function as a tumor promoter through phosphorylation of its Ser-165 residue, leading to the activation of the NF-κB signaling pathway (1). In this study, using mass spectrometry analysis, we discovered a distinct phosphorylation site, Ser-176, on YBX1. Overexpression of the YBX1-S176A (serine-to-alanine) mutant in either HEK293 cells or colon cancer HT29 cells showed dramatically reduced NF-κB-activating ability compared with that of WT-YBX1, confirming that Ser-176 phosphorylation is critical for the activation of NF-κB by YBX1. Importantly, the mutant of Ser-176 and the previously reported Ser-165 sites regulate distinct groups of NF-κB target genes, suggesting the unique and irreplaceable function of each of these two phosphorylated serine residues. Our important findings could provide a novel cancer therapy strategy by blocking either Ser-176 or Ser-165 phosphorylation or both of YBX1 in colon cancer. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Functional reconstitution of the glycine receptor

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Calvo, M.; Ruiz-Gomez, A.; Vazquez, J.; Morato, E.; Valdivieso, F.; Mayor, F. Jr. (Universidad Autonoma de Madrid (Spain))

    1989-07-25

    The functional reconstitution of the chloride channel coupled glycine receptor is described. Glycine receptors were purified from the cholate extract of rat spinal cord membranes by affinity chromatography and incorporated into phospholipid vesicles by the addition of phosphatidylcholine and removal of detergent by gel filtration. The reconstituted vesicles showed the same polypeptide composition as the purified receptor. The pharmacological characteristics of the glycine receptor were also preserved in the proteoliposomes, as demonstrated by the displacement of ({sup 3}H)strychnine binding by several glycinergic ligands and by photoaffinity labeling experiments. In order to observe functional responses (i.e., specific agonist-induced anion translocation), the authors have developed an assay based on the fluorescence quenching of an anion-sensitive entrapped probe, SPQ (6-methoxy-N-(3-sulfopropyl)quinolinium). Reconstituted vesicles were loaded with the fluorescent probe during a freeze-thaw-sonication cycle in the presence of added liposomes containing cholesterol. In such a reconstituted system, glycine receptor agonists are able to increase the rate of anion influx into the vesicles. The action of agonists is blocked by the simultaneous presence of strychnine or other glycine antagonists. The results show that the purified 48,000- and 58,000-dalton polypeptides reconstituted into phospholipid vesicles can bind ligands and promote specific ion translocation in a way similar to the glycine receptor in its native environment.

  6. Neurotoxic Non-proteinogenic Amino Acid β-N-Methylamino-L-alanine and Its Role in Biological Systems.

    Science.gov (United States)

    Popova, A A; Koksharova, O A

    2016-08-01

    Secondary metabolites of photoautotrophic organisms have attracted considerable interest in recent years. In particular, molecules of non-proteinogenic amino acids participating in various physiological processes and capable of producing adverse ecological effects have been actively investigated. For example, the non-proteinogenic amino acid β-N-methylamino-L-alanine (BMAA) is neurotoxic to animals including humans. It is known that BMAA accumulation via the food chain can lead to development of neurodegenerative diseases in humans such as Alzheimer's and Parkinson's diseases as well as amyotrophic lateral sclerosis. Moreover, BMAA can be mistakenly incorporated into a protein molecule instead of serine. Natural sources of BMAA and methods for its detection are discussed in this review, as well as the role of BMAA in metabolism of its producers and possible mechanisms of toxicity of this amino acid in different living organisms.

  7. Alanine metabolism in acute falciparum malaria

    NARCIS (Netherlands)

    Pukrittayakamee, S.; Krishna, S.; ter Kuile, F.; Wilaiwan, O.; Williamson, D. H.; White, N. J.

    2002-01-01

    We investigated the integrity of the gluconeogenic pathway in severe malaria using alanine metabolism as a measure. Alanine disposition and liver blood flow, assessed by indocyanine green (ICG) clearance, were measured simultaneously in 10 patients with falciparum malaria (six severe and four

  8. Glycine

    DEFF Research Database (Denmark)

    Sabin, John R.; Oddershede, Jens; Sauer, Stephan P. A.

    2013-01-01

    With the advent of the use of precise ion accelerators for medical purposes, it becomes ever more important to understand the interaction of biomolecules with fast ions.  Glycine is both a protein component and a model biomolecule, and is thus an important test system.    In this report, we discu...

  9. Alanine EPR dosimetry of therapeutic irradiators

    International Nuclear Information System (INIS)

    Bugay, O.; Bartchuk, V.; Kolesnik, S.; Mazin, M.; Gaponenko, H.

    1999-01-01

    The high-dose alanine EPR dosimetry is a very precise method in the dose range 1-100 kGy. The system is used generally as the standard high-dose transfer dosimetry in many laboratories. This is comparatively expensive technique so it is important to use it as a more universal dosimetry system also in the middle and low dose ranges. The problems of the middle-dose alanine dosimetry are discussed and the solution of several problems is proposed. The alanine EPR dosimetry has been applied to the dose measurements of medical irradiators in the Kiev City Oncology Center. (author)

  10. Study on the EPR/dosimetric properties of some substituted alanines

    International Nuclear Information System (INIS)

    Gancheva, Veselka; Sagstuen, Einar; Yordanov, Nicola D.

    2006-01-01

    Polycrystalline phenyl-alanine and perdeuterated l-α-alanine (l-α-alanine-d 4 ) were studied as potential high-energy radiation-sensitive materials (RSM) for solid state/EPR dosimetry. It was found that phenyl-alanine exhibits a linear dose response in the dose region 0.1-17kGy. However, phenyl-alanine is about 10 times less sensitive to γ-irradiation than standard l-α-alanine irradiated at the same doses. Moreover, the EPR response from phenyl-alanine is unstable and, independent of the absorbed dose, decreases by about 50% within 20 days after irradiation upon storage at room temperature. γ-irradiated polycrystalline perdeuterated l-α-alanine (CD 3 CD(NH 2 )COOH) has not previously been studied at room temperature by EPR spectroscopy. The first part of the present analysis was with respect to the structure of the EPR spectrum. By spectrum simulations, the presence of at least two radiation induced free radicals, R 1 =CH 3 C*(H)COOH and R 2 =H 3 N + -C*(CH 3 )COO - , was confirmed very clearly. Both these radicals were suggested previously from EPR and ENDOR studies of standard alanine crystals. The further investigations into the potential use of alanine-d 4 as RSM, after choosing optimal EPR spectrometer settings parameters for this purpose, show that it is ca. two times more sensitive than standard l-α-alanine

  11. Role of the DELSEED Loop in Torque Transmission of F1-ATPase

    Science.gov (United States)

    Tanigawara, Mizue; Tabata, Kazuhito V.; Ito, Yuko; Ito, Jotaro; Watanabe, Rikiya; Ueno, Hiroshi; Ikeguchi, Mitsunori; Noji, Hiroyuki

    2012-01-01

    F1-ATPase is an ATP-driven rotary motor that generates torque at the interface between the catalytic β-subunits and the rotor γ-subunit. The β-subunit inwardly rotates the C-terminal domain upon nucleotide binding/dissociation; hence, the region of the C-terminal domain that is in direct contact with γ—termed the DELSEED loop—is thought to play a critical role in torque transmission. We substituted all the DELSEED loop residues with alanine to diminish specific DELSEED loop-γ interactions and with glycine to disrupt the loop structure. All the mutants rotated unidirectionally with kinetic parameters comparable to those of the wild-type F1, suggesting that the specific interactions between DELSEED loop and γ is not involved in cooperative interplays between the catalytic β-subunits. Glycine substitution mutants generated half the torque of the wild-type F1, whereas the alanine mutant generated comparable torque. Fluctuation analyses of the glycine/alanine mutants revealed that the γ-subunit was less tightly held in the α3β3-stator ring of the glycine mutant than in the wild-type F1 and the alanine mutant. Molecular dynamics simulation showed that the DELSEED loop was disordered by the glycine substitution, whereas it formed an α-helix in the alanine mutant. Our results emphasize the importance of loop rigidity for efficient torque transmissions. PMID:23009846

  12. [Dynamics of the amino acid composition of the medium during cultivation of isolated liver and kidney by the controlled perfusion method].

    Science.gov (United States)

    Barashkov, V A; Gitel'zon, I I; Nefedov, V P; Trubachev, I N

    1975-11-01

    The dynamics of the medium amino acid composition was studied during a 6-hour perfusion of dog kidney and liver by a mixture of autogenic plasma and medium 199 (a ratio of 2 : 3). In comparison to the initial level the amount of histidine during 6-hour cultivation of the kidney was found to increase 2.2 times, that of glutamic acid--1.7 times, and of alanine and lysine--1.6 times. At the same time the amount of arginine, serine and asparagic acid became 3.3 times and of glutamine and threonine--2.5 times lower. With the liver perfusion the level of glutaminic acid became 2.9 times, of alanine--2.3 times, of cystine--2 times and of glycine--1.5 times higher. With the liver perfusion the level of arginine decreased so rapidly that none was found in the medium after a 2-hour perfusion. The described method of amino acid analysis during the cultivation of the organs could serve as means for elaborating and correcting the culture media.

  13. Glycine phases formed from frozen aqueous solutions: Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Surovtsev, N. V. [Institute of Automation and Electrometry, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Adichtchev, S. V.; Malinovsky, V. K. [Institute of Automation and Electrometry, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Ogienko, A. G.; Manakov, A. Yu. [Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Drebushchak, V. A. [Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Institute of Geology and Mineralogy, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Ancharov, A. I.; Boldyreva, E. V. [Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Institute of Solid Chemistry and Mechanochemistry, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Yunoshev, A. S. [Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Lavrentiev Institute of Hydrodynamics, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation)

    2012-08-14

    Glycine phases formed when aqueous solutions were frozen and subsequently heated under different conditions were studied by Raman scattering, x-ray diffraction, and differential scanning calorimetry (DSC) techniques. Crystallization of ice I{sub h} was observed in all the cases. On cooling at the rates of 0.5 K/min and 5 K/min, glassy glycine was formed as an intermediate phase which lived about 1 min or less only, and then transformed into {beta}-polymorph of glycine. Quench cooling of glycine solutions (15% w/w) in liquid nitrogen resulted in the formation of a mixture of crystalline water ice I{sub h} and a glassy glycine, which could be preserved at cryogenic temperatures (80 K) for an indefinitely long time. This mixture remained also quite stable for some time after heating above the cryogenic temperature. Subsequent heating under various conditions resulted in the transformation of the glycine glass into an unknown crystalline phase (glycine 'X-phase') at 209-216 K, which at 218-226 K transformed into {beta}-polymorph of glycine. The 'X-phase' was characterized by Raman spectroscopy; it could be obtained in noticeable amounts using a special preparation technique and tentatively characterized by x-ray powder diffraction (P2, a= 6.648 A, b= 25.867 A, c= 5.610 A, {beta}= 113.12 Masculine-Ordinal-Indicator ); the formation of 'X-phase' from the glycine glassy phase and its transformation into {beta}-polymorph were followed by DSC. Raman scattering technique with its power for unambiguous identification of the crystalline and glassy polymorphs without limitation on the crystallite size helped us to follow the phase transformations during quenching, heating, and annealing. The experimental findings are considered in relation to the problem of control of glycine polymorphism on crystallization.

  14. Glycine phases formed from frozen aqueous solutions: Revisited

    Science.gov (United States)

    Surovtsev, N. V.; Adichtchev, S. V.; Malinovsky, V. K.; Ogienko, A. G.; Drebushchak, V. A.; Manakov, A. Yu.; Ancharov, A. I.; Yunoshev, A. S.; Boldyreva, E. V.

    2012-08-01

    Glycine phases formed when aqueous solutions were frozen and subsequently heated under different conditions were studied by Raman scattering, x-ray diffraction, and differential scanning calorimetry (DSC) techniques. Crystallization of ice Ih was observed in all the cases. On cooling at the rates of 0.5 K/min and 5 K/min, glassy glycine was formed as an intermediate phase which lived about 1 min or less only, and then transformed into β-polymorph of glycine. Quench cooling of glycine solutions (15% w/w) in liquid nitrogen resulted in the formation of a mixture of crystalline water ice Ih and a glassy glycine, which could be preserved at cryogenic temperatures (80 K) for an indefinitely long time. This mixture remained also quite stable for some time after heating above the cryogenic temperature. Subsequent heating under various conditions resulted in the transformation of the glycine glass into an unknown crystalline phase (glycine "X-phase") at 209-216 K, which at 218-226 K transformed into β-polymorph of glycine. The "X-phase" was characterized by Raman spectroscopy; it could be obtained in noticeable amounts using a special preparation technique and tentatively characterized by x-ray powder diffraction (P2, a = 6.648 Å, b = 25.867 Å, c = 5.610 Å, β = 113.12°); the formation of "X-phase" from the glycine glassy phase and its transformation into β-polymorph were followed by DSC. Raman scattering technique with its power for unambiguous identification of the crystalline and glassy polymorphs without limitation on the crystallite size helped us to follow the phase transformations during quenching, heating, and annealing. The experimental findings are considered in relation to the problem of control of glycine polymorphism on crystallization.

  15. Cloning and characterization of cDNAs encoding the complete sequence of decay-accelerating factor of human complement

    International Nuclear Information System (INIS)

    Medof, M.E.; Lublin, D.M.; Holers, V.M.; Ayers, D.J.; Getty, R.R.; Leykam, J.F.; Atkinson, J.P.; Tykocinski, M.L.

    1987-01-01

    cDNAs encoding the complement decay-accelerating factor (DAF) were isolated from HeLa and differentiated HL-60 λgt cDNA libraries by screening with a codon preference oligonucleotide corresponding to DAF NH 2 -terminal amino acids 3-14. The composite cDNA sequence showed a 347-amino acid protein preceded by an NH 2 -terminal leader peptide sequence. The translated sequence beginning at the DAF NH 2 terminus encodes four contiguous ≅ 61-amino acid long repetitive units of internal homology. The repetitive regions contain four conserved cysteines, one proline, one glycine, one glycine/alanine, four leucines/isoleucines/valines, one serine, three tyrosines/phenylalanines, and on tryptophan and show striking homology to similar regions previously identified in factor B, C2, C4 binding protein, factor H, C1r, factor XIII, interleukin 2 receptor, and serum β 2 -glycoprotein I. The consensus repeats are attached to a 70-amino acid long segment rich in serine and threonine (potential O-glycosylation sites), which is in turn followed by a stretch of hydrophobic amino acids. RNA blot analysis of HeLa and HL-60 RNA revealed three DAF mRNA species of 3.1, 2.7, and 2.0 kilobases. The results indicate that portions of the DAF gene may have evolved from a DNA element common to the above proteins, that DAF cDNA predicts a COOH-terminal anchoring polypeptide, and that distinct species of DAF message are elaborated in cells

  16. Crystal Structure of Serine Racemase that Produces Neurotransmitter font-variant:small-caps">d-Serine for Stimulation of the NMDA Receptor

    Science.gov (United States)

    Goto, Masaru

    font-variant:small-caps">d-Serine is an endogenous coagonist for the N-methyl-font-variant:small-caps">d-aspartate receptor and is involved in excitatory neurotransmission in the brain. Mammalian pyridoxal 5’-phosphate-dependent serine racemase, which is localized in the mammalian brain, catalyzes the racemization of font-variant:small-caps">l-serine to yield font-variant:small-caps">d-serine and vice versa. We have determined the structures of three forms of the mammalian enzyme homolog from Schizosaccharomyces pombe. Lys57 and Ser82 located on the protein and solvent sides, respectively, with respect to the cofactor plane, are acid-base catalysts that shuttle protons to the substrate. The modified enzyme, which has a unique lysino-font-variant:small-caps">d-alanyl residue at the active site, also binds the substrate serine in the active site, suggesting that the lysino-font-variant:small-caps">d-alanyl residue acts as a catalytic base in the same manner as Lys57 of the wild type enzyme.

  17. Medical reference dosimetry using EPR measurements of alanine

    DEFF Research Database (Denmark)

    Helt-Hansen, Jakob; Rosendal, F.; Kofoed, I.M.

    2009-01-01

    Background. Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low...... methods the proposed algorithm can be applied without normalisation of phase shifts caused by changes in the g-value of the cavity. The study shows that alanine dosimetry is a suitable candidate for medical reference dosimetry especially for quality control applications.......Background. Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low...

  18. The Origin of Amino Acids in Lunar Regolith Samples

    Science.gov (United States)

    Cook, Jamie E.; Callahan, Michael P.; Dworkin, Jason P.; Glavin, Daniel P.; McLain, Hannah L.; Noble, Sarah K.; Gibson, Everett K., Jr.

    2016-01-01

    We analyzed the amino acid content of seven lunar regolith samples returned by the Apollo 16 and Apollo 17 missions and stored under NASA curation since collection using ultrahigh-performance liquid chromatography with fluorescence detection and time-of-flight mass spectrometry. Consistent with results from initial analyses shortly after collection in the 1970s, we observed amino acids at low concentrations in all of the curated samples, ranging from 0.2 parts-per-billion (ppb) to 42.7 ppb in hot-water extracts and 14.5 ppb to 651.1 ppb in 6M HCl acid-vapor-hydrolyzed, hot-water extracts. Amino acids identified in the Apollo soil extracts include glycine, D- and L-alanine, D- and L-aspartic acid, D- and L-glutamic acid, D- and L-serine, L-threonine, and L-valine, all of which had previously been detected in lunar samples, as well as several compounds not previously identified in lunar regoliths: -aminoisobutyric acid (AIB), D-and L-amino-n-butyric acid (-ABA), DL-amino-n-butyric acid, -amino-n-butyric acid, -alanine, and -amino-n-caproic acid. We observed an excess of the L enantiomer in most of the detected proteinogenic amino acids, but racemic alanine and racemic -ABA were present in some samples.

  19. Serine protease inhibitors of parasitic helminths.

    Science.gov (United States)

    Molehin, Adebayo J; Gobert, Geoffrey N; McManus, Donald P

    2012-05-01

    Serine protease inhibitors (serpins) are a superfamily of structurally conserved proteins that inhibit serine proteases and play key physiological roles in numerous biological systems such as blood coagulation, complement activation and inflammation. A number of serpins have now been identified in parasitic helminths with putative involvement in immune regulation and in parasite survival through interference with the host immune response. This review describes the serpins and smapins (small serine protease inhibitors) that have been identified in Ascaris spp., Brugia malayi, Ancylostoma caninum Onchocerca volvulus, Haemonchus contortus, Trichinella spiralis, Trichostrongylus vitrinus, Anisakis simplex, Trichuris suis, Schistosoma spp., Clonorchis sinensis, Paragonimus westermani and Echinococcus spp. and discusses their possible biological functions, including roles in host-parasite interplay and their evolutionary relationships.

  20. Alanine racemase mutants of Burkholderia pseudomallei and Burkholderia mallei and use of alanine racemase as a non-antibiotic-based selectable marker.

    Directory of Open Access Journals (Sweden)

    Sheryl L W Zajdowicz

    Full Text Available Burkholderia pseudomallei and Burkholderia mallei are category B select agents and must be studied under BSL3 containment in the United States. They are typically resistant to multiple antibiotics, and the antibiotics used to treat B. pseudomallei or B. mallei infections may not be used as selective agents with the corresponding Burkholderia species. Here, we investigated alanine racemase deficient mutants of B. pseudomallei and B. mallei for development of non-antibiotic-based genetic selection methods and for attenuation of virulence. The genome of B. pseudomallei K96243 has two annotated alanine racemase genes (bpsl2179 and bpss0711, and B. mallei ATCC 23344 has one (bma1575. Each of these genes encodes a functional enzyme that can complement the alanine racemase deficiency of Escherichia coli strain ALA1. Herein, we show that B. pseudomallei with in-frame deletions in both bpsl2179 and bpss0711, or B. mallei with an in-frame deletion in bma1575, requires exogenous D-alanine for growth. Introduction of bpsl2179 on a multicopy plasmid into alanine racemase deficient variants of either Burkholderia species eliminated the requirement for D-alanine. During log phase growth without D-alanine, the viable counts of alanine racemase deficient mutants of B. pseudomallei and B. mallei decreased within 2 hours by about 1000-fold and 10-fold, respectively, and no viable bacteria were present at 24 hours. We constructed several genetic tools with bpsl2179 as a selectable genetic marker, and we used them without any antibiotic selection to construct an in-frame ΔflgK mutant in the alanine racemase deficient variant of B. pseudomallei K96243. In murine peritoneal macrophages, wild type B. mallei ATCC 23344 was killed much more rapidly than wild type B. pseudomallei K96243. In addition, the alanine racemase deficient mutant of B. pseudomallei K96243 exhibited attenuation versus its isogenic parental strain with respect to growth and survival in murine

  1. Alanine Racemase Mutants of Burkholderia pseudomallei and Burkholderia mallei and Use of Alanine Racemase as a Non-Antibiotic-Based Selectable Marker

    Science.gov (United States)

    Zajdowicz, Sheryl L. W.; Jones-Carson, Jessica; Vazquez-Torres, Andres; Jobling, Michael G.; Gill, Ronald E.; Holmes, Randall K.

    2011-01-01

    Burkholderia pseudomallei and Burkholderia mallei are category B select agents and must be studied under BSL3 containment in the United States. They are typically resistant to multiple antibiotics, and the antibiotics used to treat B. pseudomallei or B. mallei infections may not be used as selective agents with the corresponding Burkholderia species. Here, we investigated alanine racemase deficient mutants of B. pseudomallei and B. mallei for development of non-antibiotic-based genetic selection methods and for attenuation of virulence. The genome of B. pseudomallei K96243 has two annotated alanine racemase genes (bpsl2179 and bpss0711), and B. mallei ATCC 23344 has one (bma1575). Each of these genes encodes a functional enzyme that can complement the alanine racemase deficiency of Escherichia coli strain ALA1. Herein, we show that B. pseudomallei with in-frame deletions in both bpsl2179 and bpss0711, or B. mallei with an in-frame deletion in bma1575, requires exogenous d-alanine for growth. Introduction of bpsl2179 on a multicopy plasmid into alanine racemase deficient variants of either Burkholderia species eliminated the requirement for d-alanine. During log phase growth without d-alanine, the viable counts of alanine racemase deficient mutants of B. pseudomallei and B. mallei decreased within 2 hours by about 1000-fold and 10-fold, respectively, and no viable bacteria were present at 24 hours. We constructed several genetic tools with bpsl2179 as a selectable genetic marker, and we used them without any antibiotic selection to construct an in-frame ΔflgK mutant in the alanine racemase deficient variant of B. pseudomallei K96243. In murine peritoneal macrophages, wild type B. mallei ATCC 23344 was killed much more rapidly than wild type B. pseudomallei K96243. In addition, the alanine racemase deficient mutant of B. pseudomallei K96243 exhibited attenuation versus its isogenic parental strain with respect to growth and survival in murine peritoneal macrophages

  2. Analysis of binding properties and specificity through identification of the interface forming residues (IFR for serine proteases in silico docked to different inhibitors

    Directory of Open Access Journals (Sweden)

    da Silveira Carlos H

    2010-10-01

    Full Text Available Abstract Background Enzymes belonging to the same super family of proteins in general operate on variety of substrates and are inhibited by wide selection of inhibitors. In this work our main objective was to expand the scope of studies that consider only the catalytic and binding pocket amino acids while analyzing enzyme specificity and instead, include a wider category which we have named the Interface Forming Residues (IFR. We were motivated to identify those amino acids with decreased accessibility to solvent after docking of different types of inhibitors to sub classes of serine proteases and then create a table (matrix of all amino acid positions at the interface as well as their respective occupancies. Our goal is to establish a platform for analysis of the relationship between IFR characteristics and binding properties/specificity for bi-molecular complexes. Results We propose a novel method for describing binding properties and delineating serine proteases specificity by compiling an exhaustive table of interface forming residues (IFR for serine proteases and their inhibitors. Currently, the Protein Data Bank (PDB does not contain all the data that our analysis would require. Therefore, an in silico approach was designed for building corresponding complexes The IFRs are obtained by "rigid body docking" among 70 structurally aligned, sequence wise non-redundant, serine protease structures with 3 inhibitors: bovine pancreatic trypsin inhibitor (BPTI, ecotine and ovomucoid third domain inhibitor. The table (matrix of all amino acid positions at the interface and their respective occupancy is created. We also developed a new computational protocol for predicting IFRs for those complexes which were not deciphered experimentally so far, achieving accuracy of at least 0.97. Conclusions The serine proteases interfaces prefer polar (including glycine residues (with some exceptions. Charged residues were found to be uniquely prevalent at the

  3. Analysis of binding properties and specificity through identification of the interface forming residues (IFR) for serine proteases in silico docked to different inhibitors.

    Science.gov (United States)

    Ribeiro, Cristina; Togawa, Roberto C; Neshich, Izabella A P; Mazoni, Ivan; Mancini, Adauto L; Minardi, Raquel C de Melo; da Silveira, Carlos H; Jardine, José G; Santoro, Marcelo M; Neshich, Goran

    2010-10-20

    Enzymes belonging to the same super family of proteins in general operate on variety of substrates and are inhibited by wide selection of inhibitors. In this work our main objective was to expand the scope of studies that consider only the catalytic and binding pocket amino acids while analyzing enzyme specificity and instead, include a wider category which we have named the Interface Forming Residues (IFR). We were motivated to identify those amino acids with decreased accessibility to solvent after docking of different types of inhibitors to sub classes of serine proteases and then create a table (matrix) of all amino acid positions at the interface as well as their respective occupancies. Our goal is to establish a platform for analysis of the relationship between IFR characteristics and binding properties/specificity for bi-molecular complexes. We propose a novel method for describing binding properties and delineating serine proteases specificity by compiling an exhaustive table of interface forming residues (IFR) for serine proteases and their inhibitors. Currently, the Protein Data Bank (PDB) does not contain all the data that our analysis would require. Therefore, an in silico approach was designed for building corresponding complexes. The IFRs are obtained by "rigid body docking" among 70 structurally aligned, sequence wise non-redundant, serine protease structures with 3 inhibitors: bovine pancreatic trypsin inhibitor (BPTI), ecotine and ovomucoid third domain inhibitor. The table (matrix) of all amino acid positions at the interface and their respective occupancy is created. We also developed a new computational protocol for predicting IFRs for those complexes which were not deciphered experimentally so far, achieving accuracy of at least 0.97. The serine proteases interfaces prefer polar (including glycine) residues (with some exceptions). Charged residues were found to be uniquely prevalent at the interfaces between the "miscellaneous-virus" subfamily

  4. A Novel Insight into the Cardiotoxicity of Antineoplastic Drug Doxorubicin

    Directory of Open Access Journals (Sweden)

    Zbynek Heger

    2013-10-01

    Full Text Available Doxorubicin is a commonly used antineoplastic agent in the treatment of many types of cancer. Little is known about the interactions of doxorubicin with cardiac biomolecules. Serious cardiotoxicity including dilated cardiomyopathy often resulting in a fatal congestive heart failure may occur as a consequence of chemotherapy with doxorubicin. The purpose of this study was to determine the effect of exposure to doxorubicin on the changes in major amino acids in tissue of cardiac muscle (proline, taurine, glutamic acid, arginine, aspartic acid, leucine, glycine, valine, alanine, isoleucine, threonine, lysine and serine. An in vitro interaction study was performed as a comparison of amino acid profiles in heart tissue before and after application of doxorubicin. We found that doxorubicin directly influences myocardial amino acid representation even at low concentrations. In addition, we performed an interaction study that resulted in the determination of breaking points for each of analyzed amino acids. Lysine, arginine, β-alanine, valine and serine were determined as the most sensitive amino acids. Additionally we compared amino acid profiles of myocardium before and after exposure to doxorubicin. The amount of amino acids after interaction with doxorubicin was significantly reduced (p = 0.05. This fact points at an ability of doxorubicin to induce changes in quantitative composition of amino acids in myocardium. Moreover, this confirms that the interactions between doxorubicin and amino acids may act as another factor most likely responsible for adverse effects of doxorubicin on myocardium.

  5. Heterogeneity of D-Serine Distribution in the Human Central Nervous System

    Science.gov (United States)

    Suzuki, Masataka; Imanishi, Nobuaki; Mita, Masashi; Hamase, Kenji; Aiso, Sadakazu

    2017-01-01

    D-serine is an endogenous ligand for N-methyl-D-aspartate glutamate receptors. Accumulating evidence including genetic associations of D-serine metabolism with neurological or psychiatric diseases suggest that D-serine is crucial in human neurophysiology. However, distribution and regulation of D-serine in humans are not well understood. Here, we found that D-serine is heterogeneously distributed in the human central nervous system (CNS). The cerebrum contains the highest level of D-serine among the areas in the CNS. There is heterogeneity in its distribution in the cerebrum and even within the cerebral neocortex. The neocortical heterogeneity is associated with Brodmann or functional areas but is unrelated to basic patterns of cortical layer structure or regional expressional variation of metabolic enzymes for D-serine. Such D-serine distribution may reflect functional diversity of glutamatergic neurons in the human CNS, which may serve as a basis for clinical and pharmacological studies on D-serine modulation. PMID:28604057

  6. On the existence of 'L-alanine cadmium bromide'.

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R

    2013-12-01

    It is argued that the recently reported nonlinear optical crystal L-alanine cadmium bromide, grown by slow solvent evaporation method at room temperature [P. Ilayabarathi, J. Chandrasekaran, Spectrochim. Acta 96A (2012) 684-689] is the well-known L-alanine crystal. The isolation of L-alanine crystal is explained due to fractional crystallization. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Alanine and proline content modulate global sensitivity to discrete perturbations in disordered proteins.

    Science.gov (United States)

    Perez, Romel B; Tischer, Alexander; Auton, Matthew; Whitten, Steven T

    2014-12-01

    Molecular transduction of biological signals is understood primarily in terms of the cooperative structural transitions of protein macromolecules, providing a mechanism through which discrete local structure perturbations affect global macromolecular properties. The recognition that proteins lacking tertiary stability, commonly referred to as intrinsically disordered proteins (IDPs), mediate key signaling pathways suggests that protein structures without cooperative intramolecular interactions may also have the ability to couple local and global structure changes. Presented here are results from experiments that measured and tested the ability of disordered proteins to couple local changes in structure to global changes in structure. Using the intrinsically disordered N-terminal region of the p53 protein as an experimental model, a set of proline (PRO) and alanine (ALA) to glycine (GLY) substitution variants were designed to modulate backbone conformational propensities without introducing non-native intramolecular interactions. The hydrodynamic radius (R(h)) was used to monitor changes in global structure. Circular dichroism spectroscopy showed that the GLY substitutions decreased polyproline II (PP(II)) propensities relative to the wild type, as expected, and fluorescence methods indicated that substitution-induced changes in R(h) were not associated with folding. The experiments showed that changes in local PP(II) structure cause changes in R(h) that are variable and that depend on the intrinsic chain propensities of PRO and ALA residues, demonstrating a mechanism for coupling local and global structure changes. Molecular simulations that model our results were used to extend the analysis to other proteins and illustrate the generality of the observed PRO and alanine effects on the structures of IDPs. © 2014 Wiley Periodicals, Inc.

  8. Investigation of the thermophilic mechanism in the genus Porphyrobacter by comparative genomic analysis.

    Science.gov (United States)

    Xu, Lin; Wu, Yue-Hong; Zhou, Peng; Cheng, Hong; Liu, Qian; Xu, Xue-Wei

    2018-05-23

    Type strains of the genus Porphyrobacter belonging to the family Erythrobacteraceae and the class Alphaproteobacteria have been isolated from various environments, such as swimming pools, lake water and hot springs. P. cryptus DSM 12079 T and P. tepidarius DSM 10594 T out of all Erythrobacteraceae type strains, are two type strains that have been isolated from geothermal environments. Next-generation sequencing (NGS) technology offers a convenient approach for detecting situational types based on protein sequence differences between thermophiles and mesophiles; amino acid substitutions can lead to protein structural changes, improving the thermal stabilities of proteins. Comparative genomic studies have revealed that different thermal types exist in different taxa, and few studies have been focused on the class Alphaproteobacteria, especially the family Erythrobacteraceae. In this study, eight genomes of Porphyrobacter strains were compared to elucidate how Porphyrobacter thermophiles developed mechanisms to adapt to thermal environments. P. cryptus DSM 12079 T grew optimally at 50 °C, which was higher than the optimal growth temperature of other Porphyrobacter type strains. Phylogenomic analysis of the genus Porphyrobacter revealed that P. cryptus DSM 12079 T formed a distinct and independent clade. Comparative genomic studies uncovered that 1405 single-copy genes were shared by Porphyrobacter type strains. Alignments of single-copy proteins showed that various types of amino acid substitutions existed between P. cryptus DSM 12079 T and the other Porphyrobacter strains. The primary substitution types were changes from glycine/serine to alanine. P. cryptus DSM 12079 T was the sole thermophile within the genus Porphyrobacter. Phylogenomic analysis and amino acid frequencies indicated that amino acid substitutions might play an important role in the thermophily of P. cryptus DSM 12079 T . Bioinformatic analysis revealed that major amino acid substitutional types

  9. Elevational Variation in Soil Amino Acid and Inorganic Nitrogen Concentrations in Taibai Mountain, China.

    Directory of Open Access Journals (Sweden)

    Xiaochuang Cao

    Full Text Available Amino acids are important sources of soil organic nitrogen (N, which is essential for plant nutrition, but detailed information about which amino acids predominant and whether amino acid composition varies with elevation is lacking. In this study, we hypothesized that the concentrations of amino acids in soil would increase and their composition would vary along the elevational gradient of Taibai Mountain, as plant-derived organic matter accumulated and N mineralization and microbial immobilization of amino acids slowed with reduced soil temperature. Results showed that the concentrations of soil extractable total N, extractable organic N and amino acids significantly increased with elevation due to the accumulation of soil organic matter and the greater N content. Soil extractable organic N concentration was significantly greater than that of the extractable inorganic N (NO3--N + NH4+-N. On average, soil adsorbed amino acid concentration was approximately 5-fold greater than that of the free amino acids, which indicates that adsorbed amino acids extracted with the strong salt solution likely represent a potential source for the replenishment of free amino acids. We found no appreciable evidence to suggest that amino acids with simple molecular structure were dominant at low elevations, whereas amino acids with high molecular weight and complex aromatic structure dominated the high elevations. Across the elevational gradient, the amino acid pool was dominated by alanine, aspartic acid, glycine, glutamic acid, histidine, serine and threonine. These seven amino acids accounted for approximately 68.9% of the total hydrolyzable amino acid pool. The proportions of isoleucine, tyrosine and methionine varied with elevation, while soil major amino acid composition (including alanine, arginine, aspartic acid, glycine, histidine, leucine, phenylalanine, serine, threonine and valine did not vary appreciably with elevation (p>0.10. The compositional

  10. Solved? The reductive radiation chemistry of alanine.

    Science.gov (United States)

    Pauwels, Ewald; De Cooman, Hendrik; Waroquier, Michel; Hole, Eli O; Sagstuen, Einar

    2014-02-14

    The structural changes throughout the entire reductive radiation-induced pathway of l-α-alanine are solved on an atomistic level with the aid of periodic DFT and nudged elastic band (NEB) simulations. This yields unprecedented information on the conformational changes taking place, including the protonation state of the carboxyl group in the "unstable" and "stable" alanine radicals and the internal transformation converting these two radical variants at temperatures above 220 K. The structures of all stable radicals were verified by calculating EPR properties and comparing those with experimental data. The variation of the energy throughout the full radiochemical process provides crucial insight into the reason why these structural changes and rearrangements occur. Starting from electron capture, the excess electron quickly localizes on the carbon of a carboxyl group, which pyramidalizes and receives a proton from the amino group of a neighboring alanine molecule, forming a first stable radical species (up to 150 K). In the temperature interval 150-220 K, this radical deaminates and deprotonates at the carboxyl group, the detached amino group undergoes inversion and its methyl group sustains an internal rotation. This yields the so-called "unstable alanine radical". Above 220 K, triggered by the attachment of an additional proton on the detached amino group, the radical then undergoes an internal rotation in the reverse direction, giving rise to the "stable alanine radical", which is the final stage in the reductive radiation-induced decay of alanine.

  11. Arginine kinase in Toxocara canis: Exon-intron organization, functional analysis of site-directed mutants and evaluation of putative enzyme inhibitors.

    Science.gov (United States)

    Wickramasinghe, Susiji; Yatawara, Lalani; Nagataki, Mitsuru; Agatsuma, Takeshi

    2016-10-01

    To determine exon/intron organization of the Toxocara canis (T. canis) AK (TCAK) and to test green and black tea and several other chemicals against the activity of recombinant TCAK in the guanidino-specific region by site-directed mutants. Amplification of genomic DNA fragments containing introns was carried out by PCRs. The open-reading frame (1200 bp) of TCAK (wild type) was cloned into the BamH1/SalI site of pMAL-c2X. The maltose-binding protein-TCAK fusion protein was expressed in Escherichia coli TB1 cells. The purity of the expressed enzyme was verified by SDS-PAGE. Mutations were introduced into the guanidino-specific region and other areas of pMAL/TCAK by PCR. Enzyme activity was measured with an NADH-linked assay at 25 °C for the forward reaction (phosphagen synthesis). Arginine kinase in T. canis has a seven-exon/six-intron gene structure. The lengths of the introns ranged from 542 bp to 2 500 bp. All introns begin with gt and end with ag. Furthermore, we measured the enzyme activity of site-directed mutants of the recombinant TCAK. The K m value of the mutant (Alanine to Serine) decreased indicating a higher affinity for substrate arginine than the wild-type. The K m value of the mutant (Serine to Glycine) increased to 0.19 mM. The K m value (0.19 mM) of the double mutant (Alanine-Serine to Serine-Glycine) was slightly greater than in the wild-type (0.12 mM). In addition, several other chemicals were tested; including plant extract Azadiracta indica (A. indica), an aminoglycoside antibiotic (aminosidine), a citrus flavonoid glycoside (rutin) and a commercially available catechin mixture against TCAK. Green and black tea (1:10 dilution) produced 15% and 25% inhibition of TCAK, respectively. The extract of A. indica produced 5% inhibition of TCAK. Moreover, green and black tea produced a non-competitive type of inhibition and A. indica produced a mixed-type of inhibition on TCAK. Arginine kinase in T. canis has a seven-exon/six-intron gene

  12. Depolarization-induced release of amino acids from the vestibular nuclear complex.

    Science.gov (United States)

    Godfrey, Donald A; Sun, Yizhe; Frisch, Christopher; Godfrey, Matthew A; Rubin, Allan M

    2012-04-01

    There is evidence from immunohistochemistry, quantitative microchemistry, and pharmacology for several amino acids as neurotransmitters in the vestibular nuclear complex (VNC), including glutamate, γ-aminobutyrate (GABA), and glycine. However, evidence from measurements of release has been limited. The purpose of this study was to measure depolarization-stimulated calcium-dependent release of amino acids from the VNC in brain slices. Coronal slices containing predominantly the VNC were prepared from rats and perfused with artificial cerebrospinal fluid (ACSF) in an interface chamber. Fluid was collected from the chamber just downstream from the VNC using a microsiphon. Depolarization was induced by 50 mM potassium in either control calcium and magnesium concentrations or reduced calcium and elevated magnesium. Amino acid concentrations in effluent fluid were measured by high performance liquid chromatography. Glutamate release increased fivefold during depolarization in control calcium concentration and twofold in low calcium/high magnesium. These same ratios were 6 and 1.5 for GABA, 2 and 1.3 for glycine, and 2 and 1.5 for aspartate. Differences between release in control and low calcium/high magnesium ACSF were statistically significant for glutamate, GABA, and glycine. Glutamine release decreased during and after depolarization, and taurine release slowly increased. No evidence for calcium-dependent release was found for serine, glutamine, alanine, threonine, arginine, taurine, or tyrosine. Our results support glutamate and GABA as major neurotransmitters in the VNC. They also support glycine as a neurotransmitter and some function for taurine.

  13. Mutation of serine 1333 in the ATR HEAT repeats creates a hyperactive kinase.

    Directory of Open Access Journals (Sweden)

    Jessica W Luzwick

    Full Text Available Subcellular localization, protein interactions, and post-translational modifications regulate the DNA damage response kinases ATR, ATM, and DNA-PK. During an analysis of putative ATR phosphorylation sites, we found that a single mutation at S1333 creates a hyperactive kinase. In vitro and in cells, mutation of S1333 to alanine (S1333A-ATR causes elevated levels of kinase activity with and without the addition of the protein activator TOPBP1. S1333 mutations to glycine, arginine, or lysine also create a hyperactive kinase, while mutation to aspartic acid decreases ATR activity. S1333A-ATR maintains the G2 checkpoint and promotes completion of DNA replication after transient exposure to replication stress but the less active kinase, S1333D-ATR, has modest defects in both of these functions. While we find no evidence that S1333 is phosphorylated in cultured cells, our data indicate that small changes in the HEAT repeats can have large effects on kinase activity. These mutants may serve as useful tools for future studies of the ATR pathway.

  14. Sensitization of glycine (spectrophotometric read-out) dosimetric system using sorbitol

    International Nuclear Information System (INIS)

    Shinde, S.H.; Mukherjee, T.

    2009-01-01

    Glycine spectrophotometric read-out systems have a useful dose range of 15-4000 Gy. An attempt was made to sensitize it using sorbitol as a sensitizer. Optimum compositions of aqueous acidic solutions of ferrous ammonium sulphate-xylenol orange (XO), i.e. FX and sorbitol-ferrous ammonium sulphate-xylenol orange, i.e. SFX, for 400 mg of glycine, which gives maximum dosimetric response for any given dose, were established. Molar absorption coefficient values of ferric-XO-glycine complex, i.e. ε-values, were determined for glycine system in FX and SFX. These values were found to be 8410 and 15,000 m 2 mol -1 respectively, indicating that an enhancement or sensitivity factor of about 1.78 can be achieved by sorbitol for glycine in SFX. This factor was further confirmed by measuring the gamma dose response of glycine in FX and in SFX for four different doses, viz. 37.8, 75.5, 151 and 302 Gy. It was observed that dose response of glycine in SFX is about 77% more than that of glycine in FX. The maximum variation observed in response of glycine in FX or SFX was found to be within ±1.5%.

  15. The effect of ammonium sulfate on the solubility of amino acids in water at (298.15 and 323.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Luisa A.; Macedo, Eugenia A. [Laboratory of Separation and Reaction Engineering, Departamento de Engenharia Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Pinho, Simao P. [Laboratory of Separation and Reaction Engineering, Departamento de Tecnologia Quimica e Biologica, Instituto Politecnico de Braganca, Campus e Santa Apolonia, 5301-857 Braganca (Portugal)], E-mail: spinho@ipb.pt

    2009-02-15

    Using the analytical gravimetric method the solubility of glycine, DL-alanine, L-isoleucine, L-threonine, and L-serine in aqueous systems of (NH{sub 4}){sub 2}SO{sub 4}, at (298.15 and 323.15) K, were measured for salt concentrations ranging up to 2.0 molal. In the electrolyte molality range studied the experimental observations showed that ammonium sulfate is a salting-in agent for most of the amino acids studied. Furthermore, the change of the relative solubility with electrolyte concentration shows a maximum, which makes the representation of the data by a simple empirical correlation such as the Setschenow equation difficult. For the development and evaluation of a robust thermodynamic framework that makes it possible to more profoundly understand aqueous amino acid solutions with ammonium sulfate additional experimental information is needed.

  16. GABA, 5-HT and amino acids in the rotifers Brachionus plicatilis and Brachionus rotundiformis.

    Science.gov (United States)

    Gallardo, W G; Hagiwara, A; Hara, K; Soyano, K; Snell, T W

    2000-11-01

    gamma-Aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT) have been shown to increase the reproduction of the Brachionus plicatilis (NH3L strain). In the present study, the endogenous presence of GABA and 5-HT in the rotifers B. plicatilis (NH3L and Kamiura strains) and Brachionus rotundiformis (Langkawi strain) were confirmed by dot blot immunoassay and high-performance liquid chromatography (HPLC). HPLC showed that GABA and 5-HT concentrations in the three rotifer strains range from 71 to 188 pmol/mg and from 12 to 64 pmol/mg, respectively. A total of 33 amino acids were also detected in B. plicatilis and B. rotundiformis, with glutamic acid, serine, glycine, taurine, threonine, alanine, arginine, proline, valine and isoleucine in high concentrations relative to other amino acids.

  17. Role of the mitochondrial amino acid pool in the differential sensitivity of erythroid and myeloid cells to chloramphenicol

    International Nuclear Information System (INIS)

    Abou-Khalil, S.; Abou-Khalil, W.H.; Whitney, P.L.; Yunis, A.A.

    1986-01-01

    Previous studies in the authors laboratory have suggested that mitochondrial amino acid (AA) pool is involved in the differential sensitivity of erythroid and myeloid cells to chloramphenicol (CAP). The present study examines the role of AA pool by analysis of its composition and testing the effects of its major components. The endogenous AA composition of isolated mitochondria protein was determined using a JEOL 5AH AA analyzer. L-( 14 C) leucine incorporation into mitochondrial protein was used to measure the rate of protein synthesis. Analysis of the endogenous pool in erythroleukemia (EM) and chloroleukemia (CM) mitochrondria showed similar total amount of AAs. However, some AAs were present in significantly higher or lower quantity within EM and CM (i.e. EM had about 2-fold higher glycine content). When compensating for each low AA addition of that particular acid to the reaction medium, only glycine and serine had significant effect. Thus, the addition of increasing concentrations of glycine or serine enhanced the sensitivity to CAP from 14% to 49-51% in CM but not in EM. Other AAs gave little or no effect. Since glycine is one of the first reactants in heme biosynthesis within mitochondria and is interconvertible with serine, it would appear that erythroid cells sensitivity to CAP is determined by the mitochondrial glycine-serine pool and may be somehow related of the pathway to heme biosynthesis in these cells

  18. Comparative mapping of the wild perennial Glycine latifolia and soybean (G. max reveals extensive chromosome rearrangements in the genus Glycine.

    Directory of Open Access Journals (Sweden)

    Sungyul Chang

    Full Text Available Soybean (Glycine max L. Mer., like many cultivated crops, has a relatively narrow genetic base and lacks diversity for some economically important traits. Glycine latifolia (Benth. Newell & Hymowitz, one of the 26 perennial wild Glycine species related to soybean in the subgenus Glycine Willd., shows high levels of resistance to multiple soybean pathogens and pests including Alfalfa mosaic virus, Heterodera glycines Ichinohe and Sclerotinia sclerotiorum (Lib. de Bary. However, limited information is available on the genomes of these perennial Glycine species. To generate molecular resources for gene mapping and identification, high-density linkage maps were constructed for G. latifolia using single nucleotide polymorphism (SNP markers generated by genotyping by sequencing and evaluated in an F2 population and confirmed in an F5 population. In each population, greater than 2,300 SNP markers were selected for analysis and segregated to form 20 large linkage groups. Marker orders were similar in the F2 and F5 populations. The relationships between G. latifolia linkage groups and G. max and common bean (Phaseolus vulgaris L. chromosomes were examined by aligning SNP-containing sequences from G. latifolia to the genome sequences of G. max and P. vulgaris. Twelve of the 20 G. latifolia linkage groups were nearly collinear with G. max chromosomes. The remaining eight G. latifolia linkage groups appeared to be products of multiple interchromosomal translocations relative to G. max. Large syntenic blocks also were observed between G. latifolia and P. vulgaris. These experiments are the first to compare genome organizations among annual and perennial Glycine species and common bean. The development of molecular resources for species closely related to G. max provides information into the evolution of genomes within the genus Glycine and tools to identify genes within perennial wild relatives of cultivated soybean that could be beneficial to soybean

  19. Alanine-ESR dosimetry for radiotherapy IAEA experience

    International Nuclear Information System (INIS)

    Mehta, K.; Girzikowsky, R.; )

    1997-01-01

    At present, the most commonly used transfer dosimeters for radiotherapy applications are TL dosemeters. They are being used for intercomparison between SSDLs (about 70) and the IAEA dosimetry laboratory. However, there are some undesirable characteristics of this dosimetry system. We have a study in progress at the IAEA to evaluate the alanine-ESR systems as an alternative to TLDs. There are several desirable qualities which make alanine an attractive dosemeter. Preliminary data suggest that the alanine-ESR dosimetry system has the potential to replace TLDs for intercomparison amongst SSDLs in the therapy-level dose regions. (Author)

  20. D-serine : The right or wrong isoform?

    NARCIS (Netherlands)

    Fuchs, Sabine A; Berger, Ruud; de Koning, Tom J

    2011-01-01

    Only recently, d-amino acids have been identified in mammals. Of these, d-serine has been most extensively studied. d-Serine was found to play an important role as a neurotransmitter in the human central nervous system (CNS) by binding to the N-methyl-d-aspartate receptor (NMDAr), similar to

  1. DEUTERIUM FRACTIONATION DURING AMINO ACID FORMATION BY PHOTOLYSIS OF INTERSTELLAR ICE ANALOGS CONTAINING DEUTERATED METHANOL

    Energy Technology Data Exchange (ETDEWEB)

    Oba, Yasuhiro; Watanabe, Naoki; Kouchi, Akira [Institute of Low Temperature Science, Hokkaido University, N19W8, Kita-ku, Sapporo, Hokkaido 060-0819 (Japan); Takano, Yoshinori, E-mail: oba@lowtem.hokudai.ac.jp [Department of Biogeochemistry, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka, Kanagawa 237-0061 (Japan)

    2016-08-10

    Deuterium (D) atoms in interstellar deuterated methanol might be distributed into complex organic molecules through molecular evolution by photochemical reactions in interstellar grains. In this study, we use a state-of-the-art high-resolution mass spectrometer coupled with a high-performance liquid chromatography system to quantitatively analyze amino acids and their deuterated isotopologues formed by the photolysis of interstellar ice analogs containing singly deuterated methanol CH{sub 2}DOH at 10 K. Five amino acids (glycine, α -alanine, β -alanine, sarcosine, and serine) and their deuterated isotopologues whose D atoms are bound to carbon atoms are detected in organic residues formed by photolysis followed by warming up to room temperature. The abundances of singly deuterated amino acids are in the range of 0.3–1.1 relative to each nondeuterated counterpart, and the relative abundances of doubly and triply deuterated species decrease with an increasing number of D atoms in a molecule. The abundances of amino acids increase by a factor of more than five upon the hydrolysis of the organic residues, leading to decreases in the relative abundances of deuterated species for α -alanine and β -alanine. On the other hand, the relative abundances of the deuterated isotopologues of the other three amino acids did not decrease upon hydrolysis, indicating different formation mechanisms of these two groups upon hydrolysis. The present study facilitates both qualitative and quantitative evaluations of D fractionation during molecular evolution in the interstellar medium.

  2. DEUTERIUM FRACTIONATION DURING AMINO ACID FORMATION BY PHOTOLYSIS OF INTERSTELLAR ICE ANALOGS CONTAINING DEUTERATED METHANOL

    International Nuclear Information System (INIS)

    Oba, Yasuhiro; Watanabe, Naoki; Kouchi, Akira; Takano, Yoshinori

    2016-01-01

    Deuterium (D) atoms in interstellar deuterated methanol might be distributed into complex organic molecules through molecular evolution by photochemical reactions in interstellar grains. In this study, we use a state-of-the-art high-resolution mass spectrometer coupled with a high-performance liquid chromatography system to quantitatively analyze amino acids and their deuterated isotopologues formed by the photolysis of interstellar ice analogs containing singly deuterated methanol CH 2 DOH at 10 K. Five amino acids (glycine, α -alanine, β -alanine, sarcosine, and serine) and their deuterated isotopologues whose D atoms are bound to carbon atoms are detected in organic residues formed by photolysis followed by warming up to room temperature. The abundances of singly deuterated amino acids are in the range of 0.3–1.1 relative to each nondeuterated counterpart, and the relative abundances of doubly and triply deuterated species decrease with an increasing number of D atoms in a molecule. The abundances of amino acids increase by a factor of more than five upon the hydrolysis of the organic residues, leading to decreases in the relative abundances of deuterated species for α -alanine and β -alanine. On the other hand, the relative abundances of the deuterated isotopologues of the other three amino acids did not decrease upon hydrolysis, indicating different formation mechanisms of these two groups upon hydrolysis. The present study facilitates both qualitative and quantitative evaluations of D fractionation during molecular evolution in the interstellar medium.

  3. Occurrence of β-N-methylamino-l-alanine (BMAA and Isomers in Aquatic Environments and Aquatic Food Sources for Humans

    Directory of Open Access Journals (Sweden)

    Emilie Lance

    2018-02-01

    Full Text Available The neurotoxin β-N-methylamino-l-alanine (BMAA, a non-protein amino acid produced by terrestrial and aquatic cyanobacteria and by micro-algae, has been suggested to play a role as an environmental factor in the neurodegenerative disease Amyotrophic Lateral Sclerosis-Parkinsonism-Dementia complex (ALS-PDC. The ubiquitous presence of BMAA in aquatic environments and organisms along the food chain potentially makes it public health concerns. However, the BMAA-associated human health risk remains difficult to rigorously assess due to analytical challenges associated with the detection and quantification of BMAA and its natural isomers, 2,4-diamino butyric acid (DAB, β-amino-N-methyl-alanine (BAMA and N-(2-aminoethyl glycine (AEG. This systematic review, reporting the current knowledge on the presence of BMAA and isomers in aquatic environments and human food sources, was based on a selection and a score numbering of the scientific literature according to various qualitative and quantitative criteria concerning the chemical analytical methods used. Results from the best-graded studies show that marine bivalves are to date the matrix containing the higher amount of BMAA, far more than most fish muscles, but with an exception for shark cartilage. This review discusses the available data in terms of their use for human health risk assessment and identifies knowledge gaps requiring further investigations.

  4. Occurrence of β-N-methylamino-l-alanine (BMAA) and Isomers in Aquatic Environments and Aquatic Food Sources for Humans.

    Science.gov (United States)

    Lance, Emilie; Arnich, Nathalie; Maignien, Thomas; Biré, Ronel

    2018-02-14

    The neurotoxin β- N -methylamino-l-alanine (BMAA), a non-protein amino acid produced by terrestrial and aquatic cyanobacteria and by micro-algae, has been suggested to play a role as an environmental factor in the neurodegenerative disease Amyotrophic Lateral Sclerosis-Parkinsonism-Dementia complex (ALS-PDC). The ubiquitous presence of BMAA in aquatic environments and organisms along the food chain potentially makes it public health concerns. However, the BMAA-associated human health risk remains difficult to rigorously assess due to analytical challenges associated with the detection and quantification of BMAA and its natural isomers, 2,4-diamino butyric acid (DAB), β-amino- N -methyl-alanine (BAMA) and N -(2-aminoethyl) glycine (AEG). This systematic review, reporting the current knowledge on the presence of BMAA and isomers in aquatic environments and human food sources, was based on a selection and a score numbering of the scientific literature according to various qualitative and quantitative criteria concerning the chemical analytical methods used. Results from the best-graded studies show that marine bivalves are to date the matrix containing the higher amount of BMAA, far more than most fish muscles, but with an exception for shark cartilage. This review discusses the available data in terms of their use for human health risk assessment and identifies knowledge gaps requiring further investigations.

  5. Enhancement of L-Serine Production by Corynebacterium ...

    African Journals Online (AJOL)

    glutamicum SYPS-062 cultivation process for efficient production of L-serine on a large scale. ... central intermediate for a number of cellular .... impeller, oxygen and pH electrodes, under the ... equation. The yield of L-serine was regressed with respect to the medium ..... is not essential for activity but is required for inhibition.

  6. Serine:glyoxylate aminotransferase mutant of barley

    International Nuclear Information System (INIS)

    Blackwell, R.; Murray, A.; Joy, K.; Lea, P.

    1987-01-01

    A photorespiratory mutant of barley (LaPr 85/84), deficient in both of the major peaks of serine:glyoxylate aminotransferase activity detected in the wild type, also lacks serine:pyruvate and asparagine:glyoxylate aminotransferase activities. Genetic analysis of the mutation demonstrated that these three activities are all carried on the same enzyme. The mutant, when placed in air, accumulated a large pool of serine, showed the expected rate (50%) of ammonia release during photorespiration but produced CO 2 at twice the wild type rate when it was fed [ 14 C] glyoxylate. Compared with the wild type, LaPr 85/84 exhibited abnormal transient changes in chlorophyll a fluorescence when the CO 2 concentration of the air was altered, indicating that the rates of the fluorescence quenching mechanisms were affected in vivo by the lack of this enzyme

  7. A role for accumbal glycine receptors in modulation of dopamine release by the glycine transporter-1 inhibitor Org25935

    Directory of Open Access Journals (Sweden)

    Helga eHöifödt Lidö

    2011-03-01

    Full Text Available AbstractAccumbal glycine modulates basal and ethanol-induced dopamine levels in the nucleus accumbens (nAc as well as voluntary ethanol consumption. Also, systemic administration of the glycine transporter-1 inhibitor Org25935 elevates dopamine levels in nAc, prevents a further ethanol-induced dopamine elevation and robustly and dose-dependently decreases ethanol consumption in rats. Here we investigated whether Org25935 applied locally in nAc modulates dopamine release, and whether accumbal glycine receptors or NMDA receptors are involved in this tentative effect. We also addressed whether Org25935 and ethanol applied locally in nAc interact with dopamine levels, as seen after systemic administration. We used in vivo microdialysis coupled to HPLC-ED in freely moving male Wistar rats to monitor dopamine output in nAc after local perfusion of Org25935 alone, with ethanol, or Org25935-perfusion after pre-treatment with the glycine receptor antagonist strychnine or the NMDA receptor glycine site antagonist L-701.324. Local Org25935 increased extracellular dopamine levels in a subpopulation of rats. Local strychnine, but not systemic L-701.324, antagonized the dopamine-activating effect of Org25935. Ethanol failed to induce a dopamine overflow in the subpopulation responding to Org25935 with a dopamine elevation. The study supports a role for accumbal glycine receptors rather than NMDA receptor signaling in the dopamine-activating effect of Org25935. The results further indicate that the previously reported systemic Org25935-ethanol interaction with regard to accumbal dopamine is localized to the nAc. This adds to the growing evidence for the glycine receptor as an important player in the dopamine reward circuitry and in ethanol’s effects within this system.

  8. Glycine and a glycine dehydrogenase (GLDC) SNP as citalopram/escitalopram response biomarkers in depression: pharmacometabolomics-informed pharmacogenomics.

    Science.gov (United States)

    Ji, Y; Hebbring, S; Zhu, H; Jenkins, G D; Biernacka, J; Snyder, K; Drews, M; Fiehn, O; Zeng, Z; Schaid, D; Mrazek, D A; Kaddurah-Daouk, R; Weinshilboum, R M

    2011-01-01

    Major depressive disorder (MDD) is a common psychiatric disease. Selective serotonin reuptake inhibitors (SSRIs) are an important class of drugs used in the treatment of MDD. However, many patients do not respond adequately to SSRI therapy. We used a pharmacometabolomics-informed pharmacogenomic research strategy to identify citalopram/escitalopram treatment outcome biomarkers. Metabolomic assay of plasma samples from 20 escitalopram remitters and 20 nonremitters showed that glycine was negatively associated with treatment outcome (P = 0.0054). This observation was pursued by genotyping tag single-nucleotide polymorphisms (SNPs) for genes encoding glycine synthesis and degradation enzymes, using 529 DNA samples from SSRI-treated MDD patients. The rs10975641 SNP in the glycine dehydrogenase (GLDC) gene was associated with treatment outcome phenotypes. Genotyping for rs10975641 was carried out in 1,245 MDD patients in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, and its presence was significant (P = 0.02) in DNA taken from these patients. These results highlight a possible role for glycine in SSRI response and illustrate the use of pharmacometabolomics to "inform" pharmacogenomics.

  9. Amperometric Self-Referencing Ceramic Based Microelectrode Arrays for D-Serine Detection.

    Science.gov (United States)

    Campos-Beltrán, Diana; Konradsson-Geuken, Åsa; Quintero, Jorge E; Marshall, Lisa

    2018-03-06

    D-serine is the major D-amino acid in the mammalian central nervous system. As the dominant co-agonist of the endogenous synaptic NMDA receptor, D-serine plays a role in synaptic plasticity, learning, and memory. Alterations in D-serine are linked to neuropsychiatric disorders including schizophrenia. Thus, it is of increasing interest to monitor the concentration of D-serine in vivo as a relevant player in dynamic neuron-glia network activity. Here we present a procedure for amperometric detection of D-serine with self-referencing ceramic-based microelectrode arrays (MEAs) coated with D-amino acid oxidase from the yeast Rhodotorula gracilis (RgDAAO). We demonstrate in vitro D-serine recordings with a mean sensitivity of 8.61 ± 0.83 pA/µM to D-serine, a limit of detection (LOD) of 0.17 ± 0.01 µM, and a selectivity ratio of 80:1 or greater for D-serine over ascorbic acid (mean ± SEM; n = 12) that can be used for freely moving studies.

  10. The re-assimilation of ammonia produced by photorespiration and the nitrogen economy of C3 higher plants.

    Science.gov (United States)

    Keys, Alfred J

    2006-02-01

    Photorespiration involves the conversion of glycine to serine with the release of ammonia and CO(2). In C(3) terrestrial higher plants the flux through glycine and serine is so large that it results in the production of ammonia at a rate far exceeding that from reduction of new nitrogen entering the plant. The photorespiratory nitrogen cycle re-assimilates this ammonia using the enzymes glutamine synthetase and glutamine:2-oxoglutarateaminotransferase.

  11. Performance effects of acute β-alanine induced paresthesia in competitive cyclists.

    Science.gov (United States)

    Bellinger, Phillip M; Minahan, Clare L

    2016-01-01

    β-alanine is a common ingredient in supplements consumed by athletes. Indeed, athletes may believe that the β-alanine induced paresthesia, experienced shortly after ingestion, is associated with its ergogenic effect despite no scientific mechanism supporting this notion. The present study examined changes in cycling performance under conditions of β-alanine induced paresthesia. Eight competitive cyclists (VO2max = 61.8 ± 4.2 mL·kg·min(-1)) performed three practices, one baseline and four experimental trials. The experimental trials comprised a 1-km cycling time trial under four conditions with varying information (i.e., athlete informed β-alanine or placebo) and supplement content (athlete received β-alanine or placebo) delivered to the cyclist: informed β-alanine/received β-alanine, informed placebo/received β-alanine, informed β-alanine/received placebo and informed placebo/received placebo. Questionnaires were undertaken exploring the cyclists' experience of the effects of the experimental conditions. A possibly likely increase in mean power was associated with conditions in which β-alanine was administered (±95% CL: 2.2% ± 4.0%), but these results were inconclusive for performance enhancement (p = 0.32, effect size = 0.18, smallest worthwhile change = 56% beneficial). A possibly harmful effect was observed when cyclists were correctly informed that they had ingested a placebo (-1.0% ± 1.9%). Questionnaire data suggested that β-alanine ingestion resulted in evident sensory side effects and six cyclists reported placebo effects. Acute ingestion of β-alanine is not associated with improved 1-km TT performance in competitive cyclists. These findings are in contrast to the athlete's "belief" as cyclists reported improved energy and the ability to sustain a higher power output under conditions of β-alanine induced paresthesia.

  12. Glycine transporter 1 is a target for the treatment of epilepsy

    NARCIS (Netherlands)

    Shen, Hai-Ying; van Vliet, Erwin A.; Bright, Kerry-Ann; Hanthorn, Marissa; Lytle, Nikki K.; Gorter, Jan; Aronica, Eleonora; Boison, Detlev

    2015-01-01

    Glycine is the major inhibitory neurotransmitter in brainstem and spinal cord, whereas in hippocampus glycine exerts dual modulatory roles on strychnine-sensitive glycine receptors and on the strychnine-insensitive glycineB site of the N-methyl-D-aspartate receptor (NMDAR). In hippocampus, the

  13. Glycine transporter 1 is a target for the treatment of epilepsy

    NARCIS (Netherlands)

    Shen, H-Y; van Vliet, E.A.; Bright, K-A.; Hanthorn, M.; Lytle, N.K.; Gorter, J.; Aronica, E.; Boison, D.

    2015-01-01

    Glycine is the major inhibitory neurotransmitter in brainstem and spinal cord, whereas in hippocampus glycine exerts dual modulatory roles on strychnine-sensitive glycine receptors and on the strychnine-insensitive glycineB site of the N-methyl-d-aspartate receptor (NMDAR). In hippocampus, the

  14. Alanine - Valine dynamics in pregnant rabbits | Emudianughe ...

    African Journals Online (AJOL)

    [15N]-alanine and [15N]–valine dynamics were studied in 29 -30 days pregnant New-Zealand rabbits. Over the experimental period, there was no detectable significant difference of mean ± SD of alanine concentrations within the sampling intervals in maternal, umbilical venous and arterial blood samples suggesting that ...

  15. Fibrin(ogen)olytic activity of bumblebee venom serine protease

    International Nuclear Information System (INIS)

    Qiu Yuling; Choo, Young Moo; Yoon, Hyung Joo; Jia Jingming; Cui Zheng; Wang Dong; Kim, Doh Hoon; Sohn, Hung Dae; Jin, Byung Rae

    2011-01-01

    Bee venom is a rich source of pharmacologically active components; it has been used as an immunotherapy to treat bee venom hypersensitivity, and venom therapy has been applied as an alternative medicine. Here, we present evidence that the serine protease found in bumblebee venom exhibits fibrin(ogen)olytic activity. Compared to honeybee venom, bumblebee venom contains a higher content of serine protease, which is one of its major components. Venom serine proteases from bumblebees did not cross-react with antibodies against the honeybee venom serine protease. We provide functional evidence indicating that bumblebee (Bombus terrestris) venom serine protease (Bt-VSP) acts as a fibrin(ogen)olytic enzyme. Bt-VSP activates prothrombin and directly degrades fibrinogen into fibrin degradation products. However, Bt-VSP is not a plasminogen activator, and its fibrinolytic activity is less than that of plasmin. Taken together, our results define roles for Bt-VSP as a prothrombin activator, a thrombin-like protease, and a plasmin-like protease. These findings offer significant insight into the allergic reaction sequence that is initiated by bee venom serine protease and its potential usefulness as a clinical agent in the field of hemostasis and thrombosis. - Graphical abstract: Display Omitted Highlights: → Bumblebee venom serine protease (Bt-VSP) is a fibrin(ogen)olytic enzyme. → Bt-VSP activates prothrombin. → Bt-VSP directly degrades fibrinogen into fibrin degradation products. → Bt-VSP is a hemostatically active protein that is a potent clinical agent.

  16. IAEA reference dosimeter: Alanine-ESR

    International Nuclear Information System (INIS)

    Mehta, K.; Girzikowsky, R.

    1999-01-01

    Since 1985, the IAEA has been using alanine-ESR as a transfer dosimeter for its dose quality audit service, namely the International Dose Assurance Service. The alanine dosimeters are rod-type containing 70 wt% DL--α-alanine and 30 wt% polystyrene. We have two self-shielded gamma facilities for the calibration of the dosimetry system, where the temperature within the irradiation chamber can be controlled by a specially designed unit. A 4th order polynomial is fitted to the 16 data points in the dose range of 100 Gy to 50 kGy. The measured value of the irradiation temperature coefficient at two dose values (15 and 45 kGy) is 0.23 %/deg. C. Also, the ESR-response was followed for several dosimeters for about 8 months to study the post-irradiation effect. A value of 0.008 %/day was observed for the fading of the response for two dose values (15 and 45 kGy) and three irradiation temperatures (15, 27 and 40 deg. C). The effect of the analysis temperature on the ESR response was also studied. The combined relative uncertainty for the IAEA alanine-ESR dosimetry system is 1.5% (k=1). This includes that transferred from the primary laboratory for the dose rate measurements of the gamma facilities, dosimetry system calibration uncertainties, batch variability and uncertainty in the curve fitting procedure. This value however does not include the contribution due to the irradiation temperature correction which is applied when it differs from that during calibration; this component being specific for each dose measurement. (author)

  17. Glycine and Folate Ameliorate Models of Congenital Sideroblastic Anemia.

    Directory of Open Access Journals (Sweden)

    J Pedro Fernández-Murray

    2016-01-01

    Full Text Available Sideroblastic anemias are acquired or inherited anemias that result in a decreased ability to synthesize hemoglobin in red blood cells and result in the presence of iron deposits in the mitochondria of red blood cell precursors. A common subtype of congenital sideroblastic anemia is due to autosomal recessive mutations in the SLC25A38 gene. The current treatment for SLC25A38 congenital sideroblastic anemia is chronic blood transfusion coupled with iron chelation. The function of SLC25A38 is not known. Here we report that the SLC25A38 protein, and its yeast homolog Hem25, are mitochondrial glycine transporters required for the initiation of heme synthesis. To do so, we took advantage of the fact that mitochondrial glycine has several roles beyond the synthesis of heme, including the synthesis of folate derivatives through the glycine cleavage system. The data were consistent with Hem25 not being the sole mitochondrial glycine importer, and we identify a second SLC25 family member Ymc1, as a potential secondary mitochondrial glycine importer. Based on these findings, we observed that high levels of exogenous glycine, or 5-aminolevulinic acid (5-Ala a metabolite downstream of Hem25 in heme biosynthetic pathway, were able to restore heme levels to normal in yeast cells lacking Hem25 function. While neither glycine nor 5-Ala could ameliorate SLC25A38 congenital sideroblastic anemia in a zebrafish model, we determined that the addition of folate with glycine was able to restore hemoglobin levels. This difference is likely due to the fact that yeast can synthesize folate, whereas in zebrafish folate is an essential vitamin that must be obtained exogenously. Given the tolerability of glycine and folate in humans, this study points to a potential novel treatment for SLC25A38 congenital sideroblastic anemia.

  18. Physiological control of the distribution of translocated amino acids and amides in young soybean plants

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C D; Gorham, P R

    1959-01-01

    Each of 10 C/sup 14/-labelled amino acids or amides was introduced into young soybean plants through the cut petiole of one primary leaf. The compounds used were asparagine, glutamine, urea, aspartic acid, glutamic acid, glycine, serine, alanine, norleucine, and arginine. The rates of uptake of all the solutions except arginine were in the range 1.0 to 1.5 ..mu..l per minute. After 1 to 5 minutes, the distribution of C/sup 14/ throughout the plants was determined. Each amino acid was translocated as such without conversion to other compounds. From the point of introduction, translocation of each amino acid or amide was mainly downward toward the root; very little was translocated upward. The amount of asparagine or glutamine that was translocated into the primary leaf opposite the cut petiole increased as the leaf aged, while the amount of the other eight compounds decreased as the leaf aged. When asparagine and serine were administered together, serine moved into the young primary leaf while asparagine was excluded. Both excision of the roots and chilling the roots decreased the velocity of downward translocation of aspartic acid indicating that the roots exert a strong demand which favors translocation in a downward direction more than an upward direction in the stem. 17 references, 1 figure, 5 tables.

  19. Characterization of the l-alanine exporter AlaE of Escherichia coli and its potential role in protecting cells from a toxic-level accumulation of l-alanine and its derivatives.

    Science.gov (United States)

    Kim, Seryoung; Ihara, Kohei; Katsube, Satoshi; Hori, Hatsuhiro; Ando, Tasuke; Isogai, Emiko; Yoneyama, Hiroshi

    2015-08-01

    We previously reported that the alaE gene of Escherichia coli encodes the l-alanine exporter AlaE. The objective of this study was to elucidate the mechanism of the AlaE exporter. The minimum inhibitory concentration of l-alanine and l-alanyl-l-alanine in alaE-deficient l-alanine-nonmetabolizing cells MLA301ΔalaE was 4- and >4000-fold lower, respectively, than in the alaE-positive parent cells MLA301, suggesting that AlaE functions as an efflux pump to avoid a toxic-level accumulation of intracellular l-alanine and its derivatives. Furthermore, the growth of the alaE-deficient mutant derived from the l-alanine-metabolizing strain was strongly inhibited in the presence of a physiological level of l-alanyl-l-alanine. Intact MLA301ΔalaE and MLA301ΔalaE/pAlaE cells producing plasmid-borne AlaE, accumulated approximately 200% and 50%, respectively, of the [(3) H]l-alanine detected in MLA301 cells, suggesting that AlaE exports l-alanine. When 200 mmol/L l-alanine-loaded inverted membrane vesicles prepared from MLA301ΔalaE/pAlaE were placed in a solution containing 200 mmol/L or 0.34 μmol/L l-alanine, energy-dependent [(3) H]l-alanine accumulation occurred under either condition. This energy-dependent uphill accumulation of [(3) H]l-alanine was strongly inhibited in the presence of carbonyl cyanide m-chlorophenylhydrazone but not by dicyclohexylcarbodiimide, suggesting that the AlaE-mediated l-alanine extrusion was driven by proton motive force. Based on these results, physiological roles of the l-alanine exporter are discussed. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  20. EPR/alanine dosimetry for two therapeutic proton beams

    Energy Technology Data Exchange (ETDEWEB)

    Marrale, Maurizio, E-mail: maurizio.marrale@unipa.it [Dipartimento di Fisica e Chimica, Università di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Gruppo V Sezione INFN di Catania, Via Santa Sofia, 64, 95123 Catania (Italy); Carlino, Antonio [Dipartimento di Fisica e Chimica, Università di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); EBG MedAustron GmbH, Marie Curie-Straße 5, A-2700 Wiener Neustadt (Austria); Gallo, Salvatore [Dipartimento di Fisica e Chimica, Università di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Gruppo V Sezione INFN di Catania, Via Santa Sofia, 64, 95123 Catania (Italy); Laboratorio PH3DRA, Dipartimento di Fisica e Astronomia, Università di Catania, Via Santa Sofia 64, 95123 Catania (Italy); Longo, Anna; Panzeca, Salvatore [Dipartimento di Fisica e Chimica, Università di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Gruppo V Sezione INFN di Catania, Via Santa Sofia, 64, 95123 Catania (Italy); Bolsi, Alessandra; Hrbacek, Jan; Lomax, Tony [Center for Proton Therapy, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland)

    2016-02-01

    In this work the analysis of the electron paramagnetic resonance (EPR) response of alanine pellets exposed to two different clinical proton beams employed for radiotherapy is performed. One beam is characterized by a passive delivery technique and is dedicated to the eyes treatment (OPTIS2 beam line). Alanine pellets were irradiated with a 70 MeV proton beam corresponding to 35 mm range in eye tissue. We investigated how collimators with different sizes and shape used to conform the dose to the planned target volume influence the delivered dose. For this purpose we performed measurements with varying the collimator size (Output Factor) and the results were compared with those obtained with other dosimetric techniques (such as Markus chamber and diode detector). This analysis showed that the dosimeter response is independent of collimator diameter if this is larger than or equal to 10 mm. The other beam is characterized by an active spot-scanning technique, the Gantry1 beam line (maximum energy 230 MeV), and is used to treat deep-seated tumors. The dose linearity of alanine response in the clinical dose range was tested and the alanine dose response at selected locations in depth was measured and compared with the TPS planned dose in a quasi-clinical scenario. The alanine response was found to be linear in the dose in the clinical explored range (from 10 to 70 Gy). Furthermore, a depth dose profile in a quasi-clinical scenario was measured and compared to the dose computed by the Treatment Planning System PSIPLAN. The comparison of calibrated proton alanine measurements and TPS dose shows a difference under 1% in the SOBP and a “quenching” effect up to 4% in the distal part of SOBP. The positive dosimetric characteristics of the alanine pellets confirm the feasibility to use these detectors for “in vivo” dosimetry in clinical proton beams.

  1. EPR/alanine dosimetry for two therapeutic proton beams

    International Nuclear Information System (INIS)

    Marrale, Maurizio; Carlino, Antonio; Gallo, Salvatore; Longo, Anna; Panzeca, Salvatore; Bolsi, Alessandra; Hrbacek, Jan; Lomax, Tony

    2016-01-01

    In this work the analysis of the electron paramagnetic resonance (EPR) response of alanine pellets exposed to two different clinical proton beams employed for radiotherapy is performed. One beam is characterized by a passive delivery technique and is dedicated to the eyes treatment (OPTIS2 beam line). Alanine pellets were irradiated with a 70 MeV proton beam corresponding to 35 mm range in eye tissue. We investigated how collimators with different sizes and shape used to conform the dose to the planned target volume influence the delivered dose. For this purpose we performed measurements with varying the collimator size (Output Factor) and the results were compared with those obtained with other dosimetric techniques (such as Markus chamber and diode detector). This analysis showed that the dosimeter response is independent of collimator diameter if this is larger than or equal to 10 mm. The other beam is characterized by an active spot-scanning technique, the Gantry1 beam line (maximum energy 230 MeV), and is used to treat deep-seated tumors. The dose linearity of alanine response in the clinical dose range was tested and the alanine dose response at selected locations in depth was measured and compared with the TPS planned dose in a quasi-clinical scenario. The alanine response was found to be linear in the dose in the clinical explored range (from 10 to 70 Gy). Furthermore, a depth dose profile in a quasi-clinical scenario was measured and compared to the dose computed by the Treatment Planning System PSIPLAN. The comparison of calibrated proton alanine measurements and TPS dose shows a difference under 1% in the SOBP and a “quenching” effect up to 4% in the distal part of SOBP. The positive dosimetric characteristics of the alanine pellets confirm the feasibility to use these detectors for “in vivo” dosimetry in clinical proton beams.

  2. Alanine repeats influence protein localization in splicing speckles and paraspeckles.

    Science.gov (United States)

    Chang, Shuo-Hsiu; Chang, Wei-Lun; Lu, Chia-Chen; Tarn, Woan-Yuh

    2014-12-16

    Mammalian splicing regulatory protein RNA-binding motif protein 4 (RBM4) has an alanine repeat-containing C-terminal domain (CAD) that confers both nuclear- and splicing speckle-targeting activities. Alanine-repeat expansion has pathological potential. Here we show that the alanine-repeat tracts influence the subnuclear targeting properties of the RBM4 CAD in cultured human cells. Notably, truncation of the alanine tracts redistributed a portion of RBM4 to paraspeckles. The alanine-deficient CAD was sufficient for paraspeckle targeting. On the other hand, alanine-repeat expansion reduced the mobility of RBM4 and impaired its splicing activity. We further took advantage of the putative coactivator activator (CoAA)-RBM4 conjoined splicing factor, CoAZ, to investigate the function of the CAD in subnuclear targeting. Transiently expressed CoAZ formed discrete nuclear foci that emerged and subsequently separated-fully or partially-from paraspeckles. Alanine-repeat expansion appeared to prevent CoAZ separation from paraspeckles, resulting in their complete colocalization. CoAZ foci were dynamic but, unlike paraspeckles, were resistant to RNase treatment. Our results indicate that the alanine-rich CAD, in conjunction with its conjoined RNA-binding domain(s), differentially influences the subnuclear localization and biogenesis of RBM4 and CoAZ. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  3. Distribution and Diversity of Organic and Biological Signatures in Soils From the Atacama Desert

    Science.gov (United States)

    Sharma, Aditi

    2005-01-01

    The Atacama Desert is amongst the driest places on Earth. It is considered to be a suitable analog for the Martian surface in which to conduct studies of life and life detection. Soil samples were collected in June 2005 from the Atacama Desert and analyzed in the lab for amino acid content. HPLC was the primary tool used to analyze samples. The amino acids of interest are aspartic acid, serine, glutamic acid, glycine, and alanine. D and L isomers of each amino acid (except for glycine) were separated through HPLC. The purpose of this study is to find correlations between location of the sample collection sites and amino acid content as well as D/L isomer ratios in order to formulate theories of how different types of environments may affect the abundance and distribution of life forms. Initial analysis of data shows a general lack of or slight correlation between location and amino acid content. Some data appears to contradict the hypothesis that harsher environments would have lower amino acid content than less harsh environments. Further analysis of data is needed to come up with a more conclusive report of the distribution of amino acids in the Atacama Desert.

  4. The result of Alanine/ESR dosimetry at Wolsung unit 1

    International Nuclear Information System (INIS)

    Park, Byeong Ryong; Choi, Hoon; Lim, Young Khi

    2008-01-01

    It needs accurate estimation of radiation level for verifying machinery and cable in Nuclear Power Plant. Therefore, in this study, we used ESR(Electron Spin Resonance) system for estimate dose of Alanine dosimeter. Alanine/ESR dosimetry, already known as a dosimetric method in medical and industrial field, was applied to estimate dose quantity at cable locations within a nuclear power plant as a part of equipment qualification program. Alanine/ESR dosimetry of absorbed dose range is 1 - 100 KGy. The alanine dosimeter is not significantly affected by temperature and fading is limited to 1% per year. The alanine dosimeters were fixed on the targeted cable or nearest position to measure dose quantity to get accurate value. Alanine dosimeters were scanned by commercially used two different ESR systems, e-scan and EMX series for alanine dosimeters. To estimate more accurate dose, two environmental correction factors, irradiation temperature and dosimeter weight, were used in calculation of absorbed dose quantity. In this study, dose values which are alinine dosimeter from Wolsong unit 1 are measured by two ESR systems. And then the results was compared each other

  5. Impact of charged amino acid substitution in the transmembrane domain of L-alanine exporter, AlaE, of Escherichia coli on the L-alanine export.

    Science.gov (United States)

    Kim, Seryoung; Ihara, Kohei; Katsube, Satoshi; Ando, Tasuke; Isogai, Emiko; Yoneyama, Hiroshi

    2017-01-01

    The Escherichia coli alaE gene encodes the L-alanine exporter, AlaE, that catalyzes active export of L-alanine using proton electrochemical potential. The transporter comprises only 149 amino acid residues and four predicted transmembrane domains (TMs), which contain three charged amino acid residues. The AlaE-deficient L-alanine non-metabolizing cells (ΔalaE cells) appeared hypersusceptible to L-alanyl-L-alanine showing a minimum inhibitory concentration (MIC) of 2.5 µg/ml for the dipeptide due to a toxic accumulation of L-alanine. To elucidate the mechanism by which AlaE exports L-alanine, we replaced charged amino acid residues in the TMs, glutamic acid-30 (TM-I), arginine-45 (TM-II), and aspartic acid-84 (TM-III) with their respective charge-conserved amino acid or a net neutral cysteine. The ΔalaE cells producing R45K or R45C appeared hypersusceptible to the dipeptide, indicating that arginine-45 is essential for AlaE activity. MIC of the dipeptide in the ΔalaE cells expressing E30D and E30C was 156 µg/ml and >10,000 µg/ml, respectively, thereby suggesting that a negative charge at this position is not essential. The ΔalaE cells expressing D84E or D84C showed an MIC >10,000 and 78 µg/ml, respectively, implying that a negative charge is required at this position. These results were generally consistent with that of the L-alanine accumulation experiments in intact cells. We therefore concluded that charged amino acid residues (R45 and D84) in the AlaE transmembrane domain play a pivotal role in L-alanine export. Replacement of three cysteine residues at C22, C28 (both in TM-I), and C135 (C-terminal region) with alanine showed only a marginal effect on L-alanine export.

  6. L-alanine as a precursor of ethylamine in camellia sinensis

    International Nuclear Information System (INIS)

    Takeo, Tadakazu

    1975-01-01

    After absorption of ammonium nitrogen, nitrogen-deficient Camellia sinensis synthesized theanine following synthesis of glutamic acid and alanine. The rate of incorporation of 14 C from L-alanine U- 14 C into theanine was faster than from acetaldehyde 1-2 14 C. Incorporation of 14 C from L-alanine U- 14 C into the ethylamide of theanine was prevented by adding an excess of ethylamine to the culture solution. Green seedlings converted alanine to ethylamine more rapidly than did etiolated seedlings. (auth.)

  7. The light activated alkylation of glycine

    International Nuclear Information System (INIS)

    Knowles, H.S.

    2001-04-01

    The work contained in this thesis focuses on the light-initiated alkylation of the α-centre of glycine compounds. The elaboration of the glycines in this manner represents a versatile, clean and cost effective alternative to ionic routes to higher α-amino acids. Preliminary investigations demonstrated that a range of nitrogen protecting groups were compatible with the radical alkylation. A variety of solvents could also be used although solvents with easily removable hydrogen atoms were found to interfere with the alkylation. Furthermore, a number of photo-initiators were investigated and the use of di-tert-butyl peroxide was found to afford the desired phenylalanine products in up to 27% yield (54% based on recovered starting material) when toluene was used as the alkylating agent. A range of different precursor concentrations was investigated and it was found that the optimum concentration of the glycine precursor was 0.13 mol dm -3 ; the phenylalanine yields were reduced when the concentration was less than this value. Owing to the poor UV absorption by di-tert-butyl peroxide, benzophenone (an effective photosensitiser) was added to the reaction mixture and this was shown to increase the alkylation yields. The ratio of reagents which produced the highest yield of phenylalanine products was found to be 1 : 5 : 5 : 10 for glycine : di-tert-butyl peroxide : benzophenone : toluene. This produced the phenylalanine product in up to 37% yield (57% based on recovered starting material). A number of substituents. (e.g. F, Cl etc.) could be attached to the aromatic ring of the toluene alkylating agent, affording substituted phenylalanines in 5 - 36% under these conditions. The formation of chiral phenylalanine products was probed by reacting glycine precursors bearing chiral auxiliaries. However, low diastereoselectivities were observed; the d.r. ranged from 1 : 1.1 to 1 : 1.5 only when chiral ester and amide protecting groups were used. In the final chapter, the

  8. Analysis of an Alanine/Arginine Mixture by Using TLC/FTIR Technique

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2014-01-01

    Full Text Available We applied TLC/FTIR coupled with mapping technique to analyze an alanine/arginine mixture. Narrow band TLC plates prepared by using AgI as a stationary phase were used to separate alanine and arginine. The distribution of alanine and arginine spots was manifested by a 3D chromatogram. Alanine and arginine can be successfully separated by the narrow band TLC plate. In addition, the FTIR spectra of the separated alanine and arginine spots on the narrow band TLC plate are roughly the same as the corresponding reference IR spectra.

  9. Effect of glycine nitrogen on lettuce growth under soilless culture: a metabolomics approach to identify the main changes occurred in plant primary and secondary metabolism.

    Science.gov (United States)

    Yang, Xiao; Feng, Lei; Zhao, Li; Liu, Xiaosong; Hassani, Danial; Huang, Danfeng

    2018-01-01

    Lettuce is a significant source of antioxidants and bioactive compounds. Nitrate is a cardinal fertilizer in horticulture and influences vegetable yield and quality; however, the negative effects of nitrate on the biosynthesis of flavonoids require further study. It is expected that using fertilizers containing organic nitrogen (N) could promote the synthesis of health-promoting compounds. Lettuces were hydroponically cultured in media containing 9 mmol L -1 nitrate or 9 mmol L -1 glycine for 4 weeks. Primary and secondary metabolites were analyzed using gas chromatography/mass spectrometry (GC/MS) and ultra-performance liquid chromatography/ion mobility spectrometry/quadrupole time-of-flight mass spectrometry (UPLC/IMS/QTOF-MS). Data analysis revealed that 29 metabolites were significantly altered between nitrate and glycine treatments. Metabolites were tentatively identified by comparison with online databases, literature and standards and using collision cross-section values. Significant differences in flavonoid biosynthesis, phenolic biosynthesis and the tricarboxylic acid (TCA) cycle response were observed between N sources. Compared with nitrate, glycine promoted accumulation of glycosylated flavonoids (quercetin 3-glucoside, quercetin 3-(6″-malonyl-glucoside), luteolin 7-glucuronide, luteolin 7-glucoside), ascorbic acid and amino acids (l-valine, l-leucine, l-glutamine, asparagine, l-serine, l-ornithine, 4-aminobutanoic acid, l-phenylalanine) but reduced phenolic acids (dihydroxybenzoic acid hexose isomers 1 and 2, chicoric acid, chicoric acid isomer 1) and TCA intermediates (fumaric, malic, citric and succinic acids). The novel methodology applied in this study can be used to characterize metabolites in lettuce. Accumulation of glycosylated flavonoids, amino acids and ascorbic acid in response to glycine supply provides strong evidence supporting the idea that using amino acids as an N source alters the nutritional value of vegetable crops. © 2017

  10. A cytotoxic serine proteinase isolated from mouse submandibular gland.

    Science.gov (United States)

    Shimamura, T; Nagumo, N; Ikigai, H; Murakami, K; Okubo, S; Toda, M; Ohnishi, R; Tomita, M

    1989-08-01

    We have isolated a novel cytotoxic factor from the submandibular glands of male BALB/c mice by Sephadex G-50 gel filtration chromatography and reverse-phase HPLC. The cytotoxic factor is a serine proteinase, which belongs to the mouse glandular kallikrein (mGK) family, with an Mr of approximately 27,000. The purified serine proteinase showed cytotoxic activity against mouse thymocytes in a dose-dependent manner, and a serine proteinase inhibitor, diisopropyl fluorophosphate, blocked its cytotoxic activity.

  11. Presynaptic Glycine Receptors Increase GABAergic Neurotransmission in Rat Periaqueductal Gray Neurons

    Directory of Open Access Journals (Sweden)

    Kwi-Hyung Choi

    2013-01-01

    Full Text Available The periaqueductal gray (PAG is involved in the central regulation of nociceptive transmission by affecting the descending inhibitory pathway. In the present study, we have addressed the functional role of presynaptic glycine receptors in spontaneous glutamatergic transmission. Spontaneous EPSCs (sEPSCs were recorded in mechanically dissociated rat PAG neurons using a conventional whole-cell patch recording technique under voltage-clamp conditions. The application of glycine (100 µM significantly increased the frequency of sEPSCs, without affecting the amplitude of sEPSCs. The glycine-induced increase in sEPSC frequency was blocked by 1 µM strychnine, a specific glycine receptor antagonist. The results suggest that glycine acts on presynaptic glycine receptors to increase the probability of glutamate release from excitatory nerve terminals. The glycine-induced increase in sEPSC frequency completely disappeared either in the presence of tetrodotoxin or Cd2+, voltage-gated Na+, or Ca2+ channel blockers, suggesting that the activation of presynaptic glycine receptors might depolarize excitatory nerve terminals. The present results suggest that presynaptic glycine receptors can regulate the excitability of PAG neurons by enhancing glutamatergic transmission and therefore play an important role in the regulation of various physiological functions mediated by the PAG.

  12. Cytochrome c catalyzes the in vitro synthesis of arachidonoyl glycine

    International Nuclear Information System (INIS)

    McCue, Jeffrey M.; Driscoll, William J.; Mueller, Gregory P.

    2008-01-01

    Long chain fatty acyl glycines are an emerging class of biologically active molecules that occur naturally and produce a wide array of physiological effects. Their biosynthetic pathway, however, remains unknown. Here we report that cytochrome c catalyzes the synthesis of N-arachidonoyl glycine (NAGly) from arachidonoyl coenzyme A and glycine in the presence of hydrogen peroxide. The identity of the NAGly product was verified by isotope labeling and mass analysis. Other heme-containing proteins, hemoglobin and myoglobin, were considerably less effective in generating arachidonoyl glycine as compared to cytochrome c. The reaction catalyzed by cytochrome c in vitro points to its potential role in the formation of NAGly and other long chain fatty acyl glycines in vivo

  13. Comparative study on free amino acid composition of wild edible mushroom species.

    Science.gov (United States)

    Ribeiro, Bárbara; Andrade, Paula B; Silva, Branca M; Baptista, Paula; Seabra, Rosa M; Valentão, Patrícia

    2008-11-26

    A comparative study on the amino acid composition of 11 wild edible mushroom species (Suillus bellini, Suillus luteus, Suillus granulatus, Tricholomopsis rutilans, Hygrophorus agathosmus, Amanita rubescens, Russula cyanoxantha, Boletus edulis, Tricholoma equestre, Fistulina hepatica, and Cantharellus cibarius) was developed. To define the qualitative and quantitative profiles, a derivatization procedure with dabsyl chloride was performed, followed by HPLC-UV-vis analysis. Twenty free amino acids (aspartic acid, glutamic acid, asparagine, glutamine, serine, threonine, glycine, alanine, valine, proline, arginine, isoleucine, leucine, tryptophan, phenylalanine, cysteine, ornithine, lysine, histidine, and tyrosine) were determined. B. edulis and T. equestre were revealed to be the most nutritional species, whereas F. hepatica was the poorest. The different species exhibited distinct free amino acid profiles. The quantification of the identified compounds indicated that, in a general way, alanine was the major amino acid. The results show that the analyzed mushroom species possess moderate amino acid contents, which may be relevant from a nutritional point of view because these compounds are indispensable for human health. A combination of different mushroom species in the diet would offer good amounts of amino acids and a great diversity of palatable sensations.

  14. EPR of alanine irradiated by neutrons

    International Nuclear Information System (INIS)

    Pivovarov, S.P.; Seredavina, T.A.; Zhdanov, S.V.; Mul'gin, S.I.; Zhakparov, R.K.

    2001-01-01

    In the work the first results of EPR studies of alanine, irradiated with diverse doses at neutron cyclotron generator different conditions and on the critical reactor stand are presented. A dose linearity dependence of EPR signal is observing, the methods of γ-background contribution separation are discussed. Obtain results is giving the basis to recommendation of alanine as an effective detector irradiation. However it is demanded the farther study on clarification of radiation sensitivity value dependence on the neutron energy spectrum form

  15. Conductivity of alanine solution for high level dosimetry

    International Nuclear Information System (INIS)

    Wieser, A.; Figel, M.; Regulla, D.F.

    1993-01-01

    The amino acid alanine is well known as a dosimetric detector material for high level dosimetry. Its application is based on the formation of radicals by ionising radiation. The free radicals are earlier detected by electron spin resonance (ESR) spectroscopy or chemically after dissolving the irradiated samples. Of all these methods the ESR/alanine system is the most advanced and is suggested for reference dosimetry. At present, however, the high cost of the system is a serious handicap for a large scale routine application in radiation plants. In this study the variation of electrical conductivity of L-alanine solution with applied dose is investigated in the range from 0.5-200 kGy. The conductivity was measured with a 50 MHz RF oscillator. This readout method is uncomplicated and may be suitable for routine application. The experiments were performed with L-alanine solution in glass ampoules. (Author)

  16. Analysis of gene expression in gecko digital adhesive pads indicates significant production of cysteine- and glycine-rich beta-keratins.

    Science.gov (United States)

    Hallahan, David L; Keiper-Hrynko, Natalie M; Shang, Tanya Q; Ganzke, Thaya S; Toni, Mattia; Dalla Valle, Luisa; Alibardi, Lorenzo

    2009-01-15

    Microscopic bristles (setae) present on digital pads permit the adhesion and climbing of geckos. Keratins of setae of the lizard Gekko gecko (Tokay gecko) were analyzed by the isolation of expressed mRNAs and by the generation of an EST library. Of the 510 sequences determined, 268 (52.9%) were unique. Of these, 14 appeared to encode alpha- and 111 beta-keratins. Within the beta-keratins, we identified five groups based on nucleotide sequence comparisons. Of these, one contained the bulk of beta-keratins, with 103 EST members. The mRNAs within this major group, together with two singlets, encoded cysteine-proline-serine-rich proteins of 10-14 kDa (Ge-cprp). One of the smaller groups of transcripts encoded slightly larger glycine-proline-serine-rich proteins, of 14-19 kDa (Ge-gprp). The remaining group consisted of smaller (9 kDa) serine-tyrosine-rich beta-keratins (Ge-strp). Thus three classes could be distinguished by amino acid sequence alignment. Exact matches for some of the peptide sequences obtained from setal proteins by ms/ms sequencing occur within several of these clones. Most of the beta-keratins were basic and contained a core-box region of two beta-strand sequences, with high homology to core-boxes present in avian scale and feather beta-keratins. Core-boxes are beta-folded regions that are likely responsible for polymerization into the beta-keratin filaments. The two deduced alpha-keratins of 52.7 kDa are both acidic, and contain the typical central rod region with some homology to mammalian and avian alpha-keratins, with variable N- and C-terminal regions. Basic beta-keratins and acidic alpha-keratins may interact electrostatically to form the resistant corneous material of setae. (c) 2008 Wiley-Liss, Inc.

  17. Glycine-U-14C metabolism in young rats fed the 10% casein diets containing excess glycine

    International Nuclear Information System (INIS)

    Takeuchi, Hisanao; Wakatsuki, Tetsuo; Muramatsu, Keiichiro

    1975-01-01

    Nine hours after rats fed ad libitum for 14 days a 10% casein diet (10C), a 10% casein diet containing 7% glycine (10C7G) and a 10% casein diet containing 7% glycine with 1.4% L-arginine.HCl and 0.9% L-methionine (10C7GArgMet) were force-fed 10 ml of each diet suspension containing 5μCi of glycine-U- 14 C per 100 g of body weight, the radioactivity recoveries of 14 C in expired CO 2 , tissue components and urine were determined. The radioactivity recovery of 14 C in the expired CO 2 of the 10C7G group was generally higher than that of the 10C7GArgMet group. The recovery of 14 C in the trichloroacetic acid (TCA) soluble fraction of muscle of the 10C7G and the 10C7GArgMet groups were greater than that of the 10C group. The recoveries of 14 C in the TCA soluble fraction and protein of plasma and liver, and the muscle protein were negligible in all the groups. The amount of glycine- 14 C incorporated into the carcass lipids of the 10C7GArgMet group was larger than that of other groups. The recoveries of 14 C in the liver and muscle glycogen, and liver lipids were remarkably small in all the groups. From the above results, it was suggested that the degradation of glycine- 14 C to expiratory CO 2 was not accelerated, but the rate of incorporation of the isotope into carcass lipids was increased by the supplementation of L-arginine and L-methionine to the 10C7G diet as compared with that of rats fed the 10C7G diet. (JPN)

  18. Improved scFv Anti-HIV-1 p17 Binding Affinity Guided from the Theoretical Calculation of Pairwise Decomposition Energies and Computational Alanine Scanning

    Directory of Open Access Journals (Sweden)

    Panthip Tue-ngeun

    2013-01-01

    Full Text Available Computational approaches have been used to evaluate and define important residues for protein-protein interactions, especially antigen-antibody complexes. In our previous study, pairwise decomposition of residue interaction energies of single chain Fv with HIV-1 p17 epitope variants has indicated the key specific residues in the complementary determining regions (CDRs of scFv anti-p17. In this present investigation in order to determine whether a specific side chain group of residue in CDRs plays an important role in bioactivity, computational alanine scanning has been applied. Molecular dynamics simulations were done with several complexes of original scFv anti-p17 and scFv anti-p17mutants with HIV-1 p17 epitope variants with a production run up to 10 ns. With the combination of pairwise decomposition residue interaction and alanine scanning calculations, the point mutation has been initially selected at the position MET100 to improve the residue binding affinity. The calculated docking interaction energy between a single mutation from methionine to either arginine or glycine has shown the improved binding affinity, contributed from the electrostatic interaction with the negative favorably interaction energy, compared to the wild type. Theoretical calculations agreed well with the results from the peptide ELISA results.

  19. Free amino acids in fibromyalgia syndrome: relationship with clinical picture.

    Science.gov (United States)

    Ruggiero, Valeria; Mura, Massimiliano; Cacace, Enrico; Era, Benedetta; Peri, Marcella; Sanna, Giuseppina; Fais, Antonella

    2017-04-01

    The objectives of our study were to evaluate free amino acid (FAA) concentrations in the serum of patients affected by fibromyalgia syndrome (FMS) and to determine the relationships between FAA levels and FMS clinical parameters. Thus, serum amino acid concentrations were quantified (HPLC analysis) in 23 females with fibromyalgia (according to the American College of Rheumatology classification criteria) and 20 healthy females. The results showed significantly higher serum concentrations of aspartate, cysteine, glutamate, glycine, isoleucine, leucine, methionine, ornithine, phenylalanine, sarcosine, serine, taurine, tyrosine and valine in FMS patients vs. healthy controls. Patients with higher Fibromyalgia Impact Questionnaire (FIQ) scores showed increased levels of alanine, glutamine, isoleucine, leucine, phenylalanine, proline and valine. In conclusion, our results indicate an imbalance in some FAAs in FMS patients. Increased Glu is particularly interesting, as it could explain the deficit in monoaminergic transmission involved in pain.

  20. Alanine EPR dosimeter response in proton therapy beams

    International Nuclear Information System (INIS)

    Gall, K.; Serago, C.; Desrosiers, M.; Bensen, D.

    1997-01-01

    We report a series of measurements directed to assess the suitability of alanine as a mailable dosimeter for dosimetry quality assurance of proton radiation therapy beams. These measurements include dose-response of alanine at 140 MeV, and comparison of response vs energy with a parallel plate ionization chamber. All irradiations were made at the Harvard Cyclotron Laboratory, and the dosimeters were read at NIST. The results encourage us that alanine could be expected to serve as a mailable dosimeter with systematic error due to differential energy response no greater than 3% when doses of 25 Gy are used. (Author)

  1. Complexation of vanadium (v) with alanine in different ionic strength

    International Nuclear Information System (INIS)

    Garib, F.; Zare, K.; Fekri, H

    2002-01-01

    The formation constants of species formed in the system H ++ alanine and VO 2 + alanine have be determined in aqueous solution for 1.0 3 NaCIO 4 ,using a combination of pramiracetam and spectrophotometric techniques. The compositions of the formed complexes and their stability constants were determined ny curve fitting method and it was shown that di oxovanadium(V) forms two mononuclear 1:1 and 1:2 species with alanine of the type VO 2 L and VO 2 L 2 The protonation constant of the amino group of alanine has been determined using a computer program which employ a least-squares method. The defence of the protonation of alanine and the stability constant of the species on ionic strength are described by a Debby-huckel type equation

  2. Robotized synthesis of [3-11C]-L-alanine using reaction of asymmetric alkylation of 11CH3I nickel complex of glycine Schiff base with S-2-N-(N'-benzylpropyl)aminobenzophenone

    International Nuclear Information System (INIS)

    Mosevich, I.K.; Kuznetsova, O.F.; Vasil'ev, D.A.; Anichkov, A.A.; Korsakov, M.V.

    1999-01-01

    Synthesis of [3- 11 C]-L-alanine based on 11 CH 3 I nickel complex (1) alkylation using different solvents (tetrahydrofuran, dimethylformamide, acetonitrile, acetone) and catalysts (potassium butylate, sodium hydride) was investigated. It was shown that synthesis of amino acids labelled with 11 C based on complex (1) use permits to obtain preparations with high degree of enantiomeric enrichment. The best results (enantiomeric excess of L-alanine up to 99 %) were obtained in reaction with acetonitrile as a solvent and potassium tret-butylate as a catalyst

  3. Alanine/ESR dosimetry system for routine use in radiation processing

    International Nuclear Information System (INIS)

    Kojima, T.; Haruyama, Y.; Tachibana, H.; Tanaka, R.; Okamoto, J.; Hara, H.; Kashiwazaki, S.

    1993-01-01

    A new alanine-polystyrene(PS) dosimeter prepared with simplified molding procedure and an automatic desk-top dose-reader of alanine dosimeter were developed for the purpose of routine use. Combination of these two allows us to apply a reliable alanine/ESR dosimetry system to routine dosimetric process control in industrial gamma radiation processing. (Author)

  4. Reproducibility and signal response linearity of Alanine gel dosimeter

    International Nuclear Information System (INIS)

    Silva, Cleber Feijo Silva; Campos, Leticia Lucente

    2008-01-01

    Gel Dosimetry has been studied mainly for medical applications, because it presents signal response in the dose range used in radiotherapy treatments and it can be applied for three dimensional dosimetry. Alanine gel dosimeter is a new gel material developed at IPEN that presents significant improvement on previous alanine systems developed by Costa (1994). The DL-Alanine (C 3 H 7 NO 2 ) is an amino acid tissue equivalent that improves the production of ferric ions in the solution. These ferric ions concentration can be measured by spectrophotometry technique. This work aims to study the reproducibility of the alanine gel solutions and the signal response as a function of gamma radiation dose, considering that these two properties are very important for characterizing and standardizing any dosimeter. (author)

  5. High Energy Electron Dosimetry by Alanine/ESR Spectroscopy

    International Nuclear Information System (INIS)

    Chu, Sung Sil

    1989-01-01

    Dosimetry based on electron spin resonance(ESR) analysis of radiation induced free radicals in amino acids is relevant to biological dosimetry applications. Alanine detectors are without walls and are tissue equivalent. Therefore, alanine ESR dosimetry looks promising for use in the therapy level. The dose range of the alanine/ESR dosimetry system can be extended down to l Gy. In a water phantom the absorbed dose of electrons generated by a medical linear accelerator of different initial energies (6-21 MeV) and therapeutic dose levels(1-60 Gy) was measured. Furthermore, depth dose measurements carried out with alanine dosimeters were compared with ionization chamber measurements. As the results, the measured absorbed doses for shallow depth of initial electron energies above 15 MeV were higher by 2-5% than those calculated by nominal energy CE factors. This seems to be caused by low energy scattered beams generated from the scattering foil and electron cones of beam projecting device in medical linear accelerator

  6. Alanine Enhances Aminoglycosides-Induced ROS Production as Revealed by Proteomic Analysis

    Directory of Open Access Journals (Sweden)

    Jin-zhou Ye

    2018-01-01

    Full Text Available Metabolite-enabled killing of antibiotic-resistant pathogens by antibiotics is an attractive strategy to manage antibiotic resistance. Our previous study demonstrated that alanine or/and glucose increased the killing efficacy of kanamycin on antibiotic-resistant bacteria, whose action is through up-regulating TCA cycle, increasing proton motive force and enhancing antibiotic uptake. Despite the fact that alanine altered several metabolic pathways, other mechanisms could be potentially involved in alanine-mediated kanamycin killing of bacteria which remains to be explored. In the present study, we adopted proteomic approach to analyze the proteome changes induced by exogenous alanine. Our results revealed that the expression of three outer membrane proteins was altered and the deletion of nagE and fadL decreased the intracellular kanamycin concentration, implying their possible roles in mediating kanamycin transport. More importantly, the integrated analysis of proteomic and metabolomic data pointed out that alanine metabolism could connect to riboflavin metabolism that provides the source for reactive oxygen species (ROS production. Functional studies confirmed that alanine treatment together with kanamycin could promote ROS production that in turn potentiates the killing of antibiotic-resistant bacteria. Further investigation showed that alanine repressed the transcription of antioxidant-encoding genes, and alanine metabolism to riboflavin metabolism connected with riboflavin metabolism through TCA cycle, glucogenesis pathway and pentose phosphate pathway. Our results suggest a novel mechanism by which alanine facilitates kanamycin killing of antibiotic-resistant bacteria via promoting ROS production.

  7. Fast heavy-ion radiation damage of glycine in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Shinji [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Tsuchida, Hidetsugu, E-mail: tsuchida@nucleng.kyoto-u.ac.jp [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Quantum Science and Engineering Center, Kyoto University, Uji 611-0011 (Japan); Furuya, Ryosuke [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Majima, Takuya; Itoh, Akio [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Quantum Science and Engineering Center, Kyoto University, Uji 611-0011 (Japan)

    2016-12-15

    Fast heavy-ion radiolysis of biomolecules in aqueous solution is investigated for an atomistic understanding of radiation damage to normal cells during heavy-particle beam therapy. The smallest amino acid glycine was used as a model biomaterial. Microjets of aqueous glycine solutions under vacuum were irradiated with 4.0-MeV carbon ions corresponding to energies in the Bragg peak region. To understand the effects of the water environment on molecular damage, the yield of glycine dissociation was measured by secondary ion mass spectroscopy. The yield was significantly reduced relative to gas-phase glycine targets. This implies that the numerous water molecules surrounding a single glycine molecule act as a buffer that suppresses dissociation. This is an environmental effect similar to that observed for other biomolecular cluster targets.

  8. Efficient L-Alanine Production by a Thermo-Regulated Switch in Escherichia coli.

    Science.gov (United States)

    Zhou, Li; Deng, Can; Cui, Wen-Jing; Liu, Zhong-Mei; Zhou, Zhe-Min

    2016-01-01

    L-Alanine has important applications in food, pharmaceutical and veterinary and is used as a substrate for production of engineered thermoplastics. Microbial fermentation could reduce the production cost and promote the application of L-alanine. However, the presence of L-alanine significantly inhibit cell growth rate and cause a decrease in the ultimate L-alanine productivity. For efficient L-alanine production, a thermo-regulated genetic switch was designed to dynamically control the expression of L-alanine dehydrogenase (alaD) from Geobacillus stearothermophilus on the Escherichia coli B0016-060BC chromosome. The optimal cultivation conditions for the genetically switched alanine production using B0016-060BC were the following: an aerobic growth phase at 33 °C with a 1-h thermo-induction at 42 °C followed by an oxygen-limited phase at 42 °C. In a bioreactor experiment using the scaled-up conditions optimized in a shake flask, B0016-060BC accumulated 50.3 g biomass/100 g glucose during the aerobic growth phase and 96 g alanine/100 g glucose during the oxygen-limited phase, respectively. The L-alanine titer reached 120.8 g/l with higher overall and oxygen-limited volumetric productivities of 3.09 and 4.18 g/l h, respectively, using glucose as the sole carbon source. Efficient cell growth and L-alanine production were reached separately, by switching cultivation temperature. The results revealed the application of a thermo-regulated strategy for heterologous metabolic production and pointed to strategies for improving L-alanine production.

  9. Corrosion inhibition of nickel in H2SO4 solution by alanine

    International Nuclear Information System (INIS)

    Hamed, E.; Abd El-REhim, S.S.; El-Shahat, M.F.; Shaltot, A.M.

    2012-01-01

    Highlights: ► Corrosion of Ni in 1 M H 2 SO 4 in the absence and the presence of alanine. ► Alanine acts as a moderate mixed type inhibitor. ► Physical adsorption of alanine and formation of protective film are on Ni surface. ► Addition of KI improves the inhibition efficiency (synergistic effect). ► EFM technique is in reasonably good agreement with the different techniques used. - Abstract: The effect of alanine, as a safe inhibitor, was studied by measuring the corrosion of Ni in aerated and stagnant 1 M H 2 SO 4 solution (pH ∼0.2). Measurements were performed under various conditions using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and the new electrochemical frequency modulation (EFM) methods. The obtained results showed that the addition of alanine alone gives a moderate inhibition and acts as an anodic-type inhibitor. The inhibition is due to physical adsorption of alanine on the metal surface. The inhibition efficiency enhances with increasing alanine concentration and immersion time but decreases with rise in temperature. The apparent activation energy, E a , is higher in the presence than in the absence of alanine. Addition of I − ions greatly improves the inhibition efficiency of alanine. The synergistic effect is due to enhanced adsorption of alanine cations by chemisorbed I − anions on the metal surface. The results obtained from polarization, EIS and EFM techniques are in good agreement indicating that EFM method can be used successfully for monitoring corrosion rate of Ni in H 2 SO 4 solution with and without alanine.

  10. Preparation of α-alanine-3H by the interaction of atomic tritium heated up to 2000 K with a solid alanine target at 77 K

    International Nuclear Information System (INIS)

    Filatov, Eh.S.; Simonov, E.F.; Shishkov, A.V.; Mogil'nikov, V.P.

    1979-01-01

    Absorption of hydrogen by alanine targets, the target behaviour and the yield of α-alanine- 3 H were studied in experiments involving straight passage of H and T atoms from the sourse (2000 K) to the target (77 K) as a function of the exposure time. In the studies with 3 H 2 the radioactivity of the gas phase was decreasing more rapidly than the overall pressure of hydrogen: H 3 H accumulates more rapidly in the gas phase. Alanine decomposition products were identified. The conditions for the studies of α-alanine- 3 H are suggested

  11. Two alanine racemase genes in Salmonella typhimurium that differ in structure and function.

    OpenAIRE

    Wasserman, S A; Walsh, C T; Botstein, D

    1983-01-01

    Mutations were isolated in a previously undescribed Salmonella typhimurium gene encoding an alanine racemase essential for utilization of L-alanine as a source of carbon, energy, and nitrogen. This new locus, designated dadB, lies within one kilobase of the D-alanine dehydrogenase locus (dadA), which is also required for alanine catabolism. The dadA and dadB genes are coregulated. Mutants (including insertions) lacking the dadB alanine racemase do not require D-alanine for growth unless a mut...

  12. EPR of gamma-irradiated polycrystalline alanine-in-glass dosimeter

    International Nuclear Information System (INIS)

    Al-Karmi, Anan M.; Morsy, M.A.

    2008-01-01

    This study attempts to overcome some of the reported discrepancies in alanine-EPR reproducibility that may be related to alanine dosimeter preparation and/or EPR spectrometer settings. The dosimeters were prepared by packing pure polycrystalline L-α-alanine directly as supplied by the manufacturer in glass tubes. This dosimeter production scheme avoids any possible contribution to the EPR signal from a binding material. The dosimeters were irradiated with gamma ray to low-dose ranges typical for medical therapy (0-20 Gy). Special attention has been paid to the study of minimum detectable dose, measurement repeatability and reproducibility, and post-irradiation stability. The dosimeter exhibited a linear dose response in the dose range from 0.1 to 20 Gy. These positive properties favor the polycrystalline alanine-in-glass tube as a radiation dosimeter

  13. ACTIVATION OF A CRYPTIC D-SERINE DEAMINASE (DSD) GENE FROM PSEUDOMONAS CEPACIA 17616

    Science.gov (United States)

    D-serine inhibits growth of P. cepacia 17616; however, resistant mutants able to express an ordinarily cryptic D-serine deaminase (dsd) gene were isolated readily. The resistant strains formed high levels of a D-serine deaminase active on D-threonine as well as D-serine. IS eleme...

  14. Beta-alanine and dopamine in the reddish brown scales of Papilio butterflies

    International Nuclear Information System (INIS)

    Umebachi, Yoshishige; Ishizaki, Yumi

    1983-01-01

    (1) Reddish brown scales of the anal eye spot in the hind-wings of P. demoleus and P. machaon have been examined for β-alanine and dopamine. (2) The scales were fractionated into 70% ethanol-soluble fraction, 4% HCl-methanol-soluble fraction, and the residua l scales, and the β-alanine content of each fraction was determined. Most of the β-alanine present in the scales has been found in the residual scales. On acid hydrolysis of the residual scales, the β-alanine has been rather rapidly released, and the hydrolysate has contained a large amount of β-alanine. (3) The protein-bound brown pigment (HCl-ppt fraction), which was extracted with 1 N NaOH and precipitated by being acidified with HCl, has contained a large amount of β-alanine. In most or at least some of the β-alanine, the NH 2 -group has been proved to be free. (4) 14 C-Labelled β-alanine and 14 C-dopamine, which were injected at prepupal or pupal stage, have been incorporated in the highest degree into the residual scales. And the 14 C has been confirmed to be present in the HCl-ppt fraction. (5) All these results indicate that the pigment of the reddish brown scales contains β-alanine and dopamine. (author)

  15. Glycine uptake by microvillous and basal plasma membrane vesicles from term human placentae.

    Science.gov (United States)

    Dicke, J M; Verges, D; Kelley, L K; Smith, C H

    1993-01-01

    Like most amino acids, glycine is present in higher concentrations in the fetus than in the mother. Unlike most amino acids, animal studies suggest fetal concentrations of glycine are minimally in excess of those required for protein synthesis. Abnormal glycine utilization has also been demonstrated in small-for-gestational age human fetuses. The mechanism(s) of glycine uptake in the human placenta are unknown. In other mammalian cells glycine is a substrate for the A, ASC and Gly amino acid transport systems. In this study human placental glycine uptake was characterized using microvillous and basal plasma membrane vesicles each prepared from the same placenta. In both membranes glycine uptake was mediated predominantly by the sodium-dependent A system. Competitive inhibition studies suggest that in microvillous vesicles the small percentage of sodium-dependent glycine uptake not inhibited by methylaminoisobutyric acid (MeAIB) shares a transport system with glycine methyl ester and sarcosine, substrates of the Gly system in other tissues. In addition there are mediated sodium-independent and non-selective transport mechanisms in both plasma membranes. If fetal glycine availability is primarily contingent upon the common and highly regulated A system, glycine must compete with many other substrates potentially resulting in marginal fetal reserves, abnormal utilization and impaired growth.

  16. Evolutionary Diversification of Alanine Transaminases in Yeast: Catabolic Specialization and Biosynthetic Redundancy

    Directory of Open Access Journals (Sweden)

    Ximena Escalera-Fanjul

    2017-06-01

    Full Text Available Gene duplication is one of the major evolutionary mechanisms providing raw material for the generation of genes with new or modified functions. The yeast Saccharomyces cerevisiae originated after an allopolyploidization event, which involved mating between two different ancestral yeast species. ScALT1 and ScALT2 codify proteins with 65% identity, which were proposed to be paralogous alanine transaminases. Further analysis of their physiological role showed that while ScALT1 encodes an alanine transaminase which constitutes the main pathway for alanine biosynthesis and the sole pathway for alanine catabolism, ScAlt2 does not display alanine transaminase activity and is not involved in alanine metabolism. Moreover, phylogenetic studies have suggested that ScALT1 and ScALT2 come from each one of the two parental strains which gave rise to the ancestral hybrid. The present work has been aimed to the understanding of the properties of the ancestral type Lacchancea kluyveri LkALT1 and Kluyveromyces lactis KlALT1, alanine transaminases in order to better understand the ScALT1 and ScALT2 evolutionary history. These ancestral -type species were chosen since they harbor ALT1 genes, which are related to ScALT2. Presented results show that, although LkALT1 and KlALT1 constitute ScALT1 orthologous genes, encoding alanine transaminases, both yeasts display LkAlt1 and KlAlt1 independent alanine transaminase activity and additional unidentified alanine biosynthetic and catabolic pathway(s. Furthermore, phenotypic analysis of null mutants uncovered the fact that KlAlt1 and LkAlt1 have an additional role, not related to alanine metabolism but is necessary to achieve wild type growth rate. Our study shows that the ancestral alanine transaminase function has been retained by the ScALT1 encoded enzyme, which has specialized its catabolic character, while losing the alanine independent role observed in the ancestral type enzymes. The fact that ScAlt2 conserves 64

  17. Alanine-ESR dosimeter: application for dosimetry in industrial electron beam accelerator

    International Nuclear Information System (INIS)

    Murali, S.; Venkataramani, R.; Pushparaja; Sarma, K.S.S.; Natarajan, V.; Sastry, M.D.

    2000-01-01

    The feasibility of DL-α-alanine, as ESR dosimeter in powder form, was examined under the conditions of pulse electron accelerator used as an industrial irradiator. The investigations were carried out to examine the following aspects: (i) Alanine-ESR dose response in irradiator characteristics viz. various beam energies, beam currents, product conveying speeds, (ii) linearity of dose response of irradiated alanine signal for suitable range, (iii) dose uniformity of the irradiated samples and (iv) depth dose measurements using alanine powder dosimeters sandwiched between polyethylene layers. Experiments were carried out by varying some of the irradiator parameters at mobile mode of the conveyor (product under movement) and also at stationary mode for different EB energies and pulse rates. For estimation of EB dose, signal intensities of gamma irradiated DL--alanine powder calibrated with Fricke dosimetry have been used. Feasibility of application of alanine ESR dosimeter for low dose measurement down to 350 Gy has been experimentally established. The present studies show that under variable operating conditions of irradiator, alanine ESR dosimetry is suitable for dosimetric applications from low dose (350 Gy) to high dose (53 kgy). (author)

  18. A molecular receptor selective for zwitterionic alanine.

    Science.gov (United States)

    Rubio, Omayra H; Taouil, Rachid; Muñiz, Francisco M; Monleón, Laura M; Simón, Luis; Sanz, Francisca; Morán, Joaquín R

    2017-01-04

    A molecular receptor has been synthesized joining an aza-crown ether with a chiral chromane which mimics the oxyanion hole of the enzymes. With this receptor an apolar host-guest complex with zwitterionic alanine has been achieved through the formation of up to seven H-bonds. This complex allows the extraction of aqueous alanine to a chloroform phase, while other natural amino acids are poorly extracted or are not extracted at all. Due to the chiral nature of the receptor, enantioselective extraction from the aqueous alanine solution to a chloroform phase takes place. X-Ray analysis combined with anisotropic effects, NOE and CD studies revealed the absolute configuration of both strong and weak complexes. Modelling studies also support the proposed structures. The presence of an oxyanion-hole motif in this structure was corroborated by X-ray diffraction studies.

  19. Compound-specific nitrogen isotope analysis of D-alanine, L-alanine, and valine: application of diastereomer separation to delta15N and microbial peptidoglycan studies.

    Science.gov (United States)

    Takano, Yoshinori; Chikaraishi, Yoshito; Ogawa, Nanako O; Kitazato, Hiroshi; Ohkouchi, Naohiko

    2009-01-01

    We have developed an analytical method to determine the compound-specific nitrogen isotope compositions of individual amino acid enantiomers using gas chromatography/combustion/isotope ratio mass spectrometry. A novel derivatization of amino acid diastereomers by optically active (R)-(-)-2-butanol or (S)-(+)-2-butanol offers two advantages for nitrogen isotope analysis. First, chromatographic chiral separation can be achieved without the use of chiral stationary-phase columns. Second, the elution order of these compounds on the chromatogram can be switched by a designated esterification reaction. We applied the method to the compound-specific nitrogen isotope analysis of D- and L-alanine in a peptidoglycan derived from the cell walls of cultured bacteria (Firmicutes and Actinobacteria; Enterococcus faecalis, Staphylococcus aureus, Staphylococcus staphylolyticus, Lactobacillus acidophilus, Bacillus subtilis, Micrococcus luteus, and Streptomyces sp.), natural whole bacterial cells (Bacillus subtilis var. natto), (pseudo)-peptidoglycan from archaea (Methanobacterium sp.), and cell wall from eukaryota (Saccharomyces cerevisiae). We observed statistically significant differences in nitrogen isotopic compositions; e.g., delta15N ( per thousand vs air) in Staphylococcus staphylolyticus for d-alanine (19.2 +/- 0.5 per thousand, n = 4) and L-alanine (21.3 +/- 0.8 per thousand, n = 4) and in Bacillus subtilis for D-alanine (6.2 +/- 0.2 per thousand, n = 3) and L-alanine (8.2 +/- 0.4 per thousand, n = 3). These results suggest that enzymatic reaction pathways, including the alanine racemase reaction, produce a nitrogen isotopic difference in amino acid enantiomers, resulting in 15N-depleted D-alanine. This method is expected to facilitate compound-specific nitrogen isotope studies of amino acid stereoisomers.

  20. Dosimetry of electron and gamma radiation with DL-alanine

    International Nuclear Information System (INIS)

    Costa, Z.M. da; Campos, L.L.

    1996-01-01

    A dosimetric method based on the quantitative determination of stabilised free radicals in irradiated crystalline DL-alanine by electron spin resonance (ESR) spectroscopy was proposed as early in 1962. Since then, alanine dosemeters owing to their unique properties have been investigated by many authors and used in dosimetry of various types of radiation, namely gamma rays, electron and neutrons. Alanine is a simple aminoacid, on irradiation at room temperature predominantly free paramagnetic radicals of the type CH 3 -CH-COOH are produced. This paper reports the application of powder DL-alanine/ESR dosemeter for measurement of absorbed dose of gamma radiation from 60 Co sources and reactor nucleus and electron beams from accelerator. The obtained results give useful information about the instrumental care necessary to obtain the needed overall accuracy in determination of absorbed dose. (author)

  1. Synthesis and GGCT Inhibitory Activity of N-Glutaryl-L-alanine Analogues.

    Science.gov (United States)

    Ii, Hiromi; Yoshiki, Tatsuhiro; Hoshiya, Naoyuki; Uenishi, Jun'ichi

    2016-01-01

    γ-Glutamylcyclotransferase (GGCT) is an important enzyme that cleaves γ-glutamyl-amino acid in the γ-glutamyl cycle to release 5-oxoproline and amino acid. Eighteen N-acyl-L-alanine analogues including eleven new compounds have been synthesized and examined for their inhibitory activity against recombinant human GGCT protein. Simple N-glutaryl-L-alanine was found to be the most potent inhibitor for GGCT. Other N-glutaryl-L-alanine analogues having methyl and dimethyl substituents at the 2-position were moderately effective, while N-(3R-aminoglutary)-L-alanine, the substrate having an (R)-amino group at the 3-position or N-(N-methyl-3-azaglutaryl)-L-alanine, the substrate having an N-methyl substituent on the 3-azaglutaryl carbon, in constract, exhibited excellent inhibition properties.

  2. Stereoselective aminoacylation of a dinucleoside monophosphate by the imidazolides of DL-alanine and N-(tert-butoxycarbonyl)-DL-alanine

    Science.gov (United States)

    Profy, A. T.; Usher, D. A.

    1984-01-01

    The aminoacylation of diinosine monophosphate was studied experimentally. When the acylating agent was the imidazolide of N-(tert-butoxycarbonyl)-DL-alanine, a 40 percent enantiomeric excess of the isomer was incorporated at the 2' site and the positions of equilibrium for the reversible 2'-3' migration reaction differed for the D and L enantiomers. The reactivity of the nucleoside hydroxyl groups was found to decrease on the order 2'(3') less than internal 2' and less than 5', and the extent of the reaction was affected by the concentration of the imidazole buffer. Reaction of IpI with imidazolide of unprotected DL-alanine, by contrast, led to an excess of the D isomer at the internal 2' site. Finally, reaction with the N-carboxy anhydride of DL-alanine occurred without stereoselection. These results are found to be relevant to the study of the evolution of optical chemical activity and the origin of genetically directed protein synthesis.

  3. NMR chemical shifts in amino acids: Effects of environments, electric field, and amine group rotation

    International Nuclear Information System (INIS)

    Yoon, Young-Gui; Pfrommer, Bernd G.; Louie, Steven G.; Canning, Andrew

    2002-01-01

    The authors present calculations of NMR chemical shifts in crystalline phases of some representative amino acids such as glycine, alanine, and alanyl-alanine. To get an insight on how different environments affect the chemical shifts, they study the transition from the crystalline phase to completely isolated molecules of glycine. In the crystalline limit, the shifts are dominated by intermolecular hydrogen-bonds. In the molecular limit, however, dipole electric field effects dominate the behavior of the chemical shifts. They show that it is necessary to average the chemical shifts in glycine over geometries. Tensor components are analyzed to get the angle dependent proton chemical shifts, which is a more refined characterization method

  4. 21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alanine amino transferase (ALT/SGPT) test system... Test Systems § 862.1030 Alanine amino transferase (ALT/SGPT) test system. (a) Identification. An alanine amino transferase (ALT/SGPT) test system is a device intended to measure the activity of the...

  5. Cerebrospinal fluid D-serine concentrations in major depressive disorder negatively correlate with depression severity.

    Science.gov (United States)

    Ishiwata, Sayuri; Hattori, Kotaro; Sasayama, Daimei; Teraishi, Toshiya; Miyakawa, Tomoko; Yokota, Yuuki; Matsumura, Ryo; Nishikawa, Toru; Kunugi, Hiroshi

    2018-01-15

    D-serine is an endogenous co-agonist of N-methyl-D-aspartate receptor (NMDAR) and plays an important role in glutamate neurotransmission. Several studies suggested the possible involvement of D-serine related in the pathophysiology of psychiatric disorders including major depression disorders (MDD). We tried to examine whether cerebrospinal fluid (CSF) or plasma D-serine concentrations are altered in MDD and whether D-serine concentrations correlated with disease severity. 26 MDD patients and 27 healthy controls matched for age, sex and ethnicity were enrolled. We measured amino acids in these samples using by high-performance liquid chromatography with fluorometric detection. D-serine and L-serine, precursor of D-serine, levels in CSF or plasma were not significantly different in patients of MDD compared to controls. Furthermore, a significant correlation between D-serine levels in CSF and Hamilton Depression Rating Scale (HAMD)-17 score was observed (r = -0.65, p = 0.006). Furthermore, we found a positive correlation between CSF D-serine and HVA concentrations in MDD patients (r = 0.54, p = 0.007). CSF D-serine concentrations were correlated with those of plasma in MDD (r = 0.61, p = 0.01) but not in controls. In CSF, we also confirmed a significant correlation between D-serine and L-serine levels in MDD (r = 0.72, p depression severity and HVA concentrations and further investigation were required to reveal the effect of medication and disease heterogeneity. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. In Quest of the Alanine R3 Radical: Multivariate EPR Spectral Analyses of X-Irradiated Alanine in the Solid State.

    Science.gov (United States)

    Jåstad, Eirik O; Torheim, Turid; Villeneuve, Kathleen M; Kvaal, Knut; Hole, Eli O; Sagstuen, Einar; Malinen, Eirik; Futsaether, Cecilia M

    2017-09-28

    The amino acid l-α-alanine is the most commonly used material for solid-state electron paramagnetic resonance (EPR) dosimetry, due to the formation of highly stable radicals upon irradiation, with yields proportional to the radiation dose. Two major alanine radical components designated R1 and R2 have previously been uniquely characterized from EPR and electron-nuclear double resonance (ENDOR) studies as well as from quantum chemical calculations. There is also convincing experimental evidence of a third minor radical component R3, and a tentative radical structure has been suggested, even though no well-defined spectral signature has been observed experimentally. In the present study, temperature dependent EPR spectra of X-ray irradiated polycrystalline alanine were analyzed using five multivariate methods in further attempts to understand the composite nature of the alanine dosimeter EPR spectrum. Principal component analysis (PCA), maximum likelihood common factor analysis (MLCFA), independent component analysis (ICA), self-modeling mixture analysis (SMA), and multivariate curve resolution (MCR) were used to extract pure radical spectra and their fractional contributions from the experimental EPR spectra. All methods yielded spectral estimates resembling the established R1 spectrum. Furthermore, SMA and MCR consistently predicted both the established R2 spectrum and the shape of the R3 spectrum. The predicted shape of the R3 spectrum corresponded well with the proposed tentative spectrum derived from spectrum simulations. Thus, results from two independent multivariate data analysis techniques strongly support the previous evidence that three radicals are indeed present in irradiated alanine samples.

  7. 40 CFR 721.520 - Alanine, N-(2-carboxyethyl)-N-alkyl-, salt.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alanine, N-(2-carboxyethyl)-N-alkyl... Specific Chemical Substances § 721.520 Alanine, N-(2-carboxyethyl)-N-alkyl-, salt. (a) Chemical substance... alanine, N-(2-carboxyethyl)-N- alkyl-, salt (P-89-336) is subject to reporting under this section for the...

  8. Cross genome comparisons of serine proteases in Arabidopsis and rice

    Directory of Open Access Journals (Sweden)

    Sowdhamini R

    2006-08-01

    Full Text Available Abstract Background Serine proteases are one of the largest groups of proteolytic enzymes found across all kingdoms of life and are associated with several essential physiological pathways. The availability of Arabidopsis thaliana and rice (Oryza sativa genome sequences has permitted the identification and comparison of the repertoire of serine protease-like proteins in the two plant species. Results Despite the differences in genome sizes between Arabidopsis and rice, we identified a very similar number of serine protease-like proteins in the two plant species (206 and 222, respectively. Nearly 40% of the above sequences were identified as potential orthologues. Atypical members could be identified in the plant genomes for Deg, Clp, Lon, rhomboid proteases and species-specific members were observed for the highly populated subtilisin and serine carboxypeptidase families suggesting multiple lateral gene transfers. DegP proteases, prolyl oligopeptidases, Clp proteases and rhomboids share a significantly higher percentage orthology between the two genomes indicating substantial evolutionary divergence was set prior to speciation. Single domain architectures and paralogues for several putative subtilisins, serine carboxypeptidases and rhomboids suggest they may have been recruited for additional roles in secondary metabolism with spatial and temporal regulation. The analysis reveals some domain architectures unique to either or both of the plant species and some inactive proteases, like in rhomboids and Clp proteases, which could be involved in chaperone function. Conclusion The systematic analysis of the serine protease-like proteins in the two plant species has provided some insight into the possible functional associations of previously uncharacterised serine protease-like proteins. Further investigation of these aspects may prove beneficial in our understanding of similar processes in commercially significant crop plant species.

  9. A comparison of three materials used in ESR dosimetry: L-α-alanine, DL-α-alanine and standard bone powder. Response to Co-60 gamma radiation

    International Nuclear Information System (INIS)

    Stuglik, Z.; Sadlo, J.

    1995-01-01

    Three solid state materials: L-α-alanine, DL-α-alanine and standard bone powder were irradiated with gamma analyzed with ESR method. It was stated that the G-value of paramagnetic centres in L-α-alanine is practically the same as in DL-alpha-alanine and about 50 times higher than in non-deproteinized bone powder. The sensitivities of investigated materials are proportional to their G-values if double integrals of ESR signals are chosen as a measure of radiation effects. When first derivatives of ESR absorption bands are used to the construction of dose-response curves (peak-to-peak method) the sensitivities of all investigated materials are comparable. (author). 14 refs, 1 fig., 3 tabs

  10. Control of alanine metabolism in rat liver by transport processes or cellular metabolism.

    OpenAIRE

    Fafournoux, P; Rémésy, C; Demigné, C

    1983-01-01

    1. Factors governing hepatic utilization of alanine were studied in vivo and in vitro in rats adapted to increasing dietary protein. 2. Hepatic alanine utilization was enhanced 5-fold with a 90%-casein diet, compared with a 13%-casein diet. The increased uptake resulted from enhanced fractional extraction in the presence of high concentrations of alanine in the portal vein. 3. The increase in alanine metabolism on high-protein diets was associated with an increase in alanine aminotransferase ...

  11. Dose intercomparison study involving Fricke, ethanol chlorobenzene, PMMA and alanine dosimeters

    International Nuclear Information System (INIS)

    Lanuza, L.G.; Cabalfin, E.G.; Kojima, T.; Tachibana, H.

    1999-01-01

    A dose intercomparison study was carried out between the Philippine Nuclear Research Institute (PNRI) and Takasaki Radiation Chemistry Research Establishment, Japan Atomic Energy Research Institute (JAERI) to determine reliability of the dosimetry systems being used by PNRI employing ethanol chlorobenzene (ECB), Fricke and alanine dosimeters. The Fricke and ECB dosimeters were prepared at PNRI while the alanine-polystyrene dosimeter was provided by JAERI. Fricke or ECB dosimeters were irradiated together with alanine at PNRI gamma irradiation facilities. Analyses of the Fricke and ECB dosimeters were performed at PNRI while alanine dosimeters were analyzed at JAERI. A comparison study between alanine and polymethylmethacrylate (PMMA, Radix RN15) dosimeters was also undertaken at JAERI. The dosimeters were irradiated together under different irradiation conditions using the gamma irradiation facilities of JAERI and Radia Industry Co. Ltd. (Japan). Evaluations of PMMA and alanine dosimeters were both performed at JAERI. Result of the dose intercomparison of PNRI with the International Atomic Energy Agency through the International Dose Assurance Service (IDAS) is also presented. (author)

  12. Dose intercomparison study involving Fricke, ethanol chlorobenzene, PMMA and alanine dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Lanuza, L G; Cabalfin, E G [Philippine Nuclear Research Institute, Quezon City (Philippines); Kojima, T; Tachibana, H [Takasaki Radiation Chemistry Research Establishment, Japan Atomic Energy Research institute, Takasaki (Japan)

    1999-03-01

    A dose intercomparison study was carried out between the Philippine Nuclear Research Institute (PNRI) and Takasaki Radiation Chemistry Research Establishment, Japan Atomic Energy Research Institute (JAERI) to determine reliability of the dosimetry systems being used by PNRI employing ethanol chlorobenzene (ECB), Fricke and alanine dosimeters. The Fricke and ECB dosimeters were prepared at PNRI while the alanine-polystyrene dosimeter was provided by JAERI. Fricke or ECB dosimeters were irradiated together with alanine at PNRI gamma irradiation facilities. Analyses of the Fricke and ECB dosimeters were performed at PNRI while alanine dosimeters were analyzed at JAERI. A comparison study between alanine and polymethylmethacrylate (PMMA, Radix RN15) dosimeters was also undertaken at JAERI. The dosimeters were irradiated together under different irradiation conditions using the gamma irradiation facilities of JAERI and Radia Industry Co. Ltd. (Japan). Evaluations of PMMA and alanine dosimeters were both performed at JAERI. Result of the dose intercomparison of PNRI with the International Atomic Energy Agency through the International Dose Assurance Service (IDAS) is also presented. (author) 8 refs, 3 figs, 4 tabs

  13. The antiproton depth–dose curve measured with alanine detectors

    CERN Document Server

    Bassler, Niels; Palmans, Hugo; Holzscheiter, Michael H; Kovacevic, Sandra

    2008-01-01

    n this paper we report on the measurement of the antiproton depth–dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen and Olsen for conversion of calculated dose into response. A good agreement is observed between the measured and calculated relative effectiveness although an underestimation of the measured values beyond the Bragg-peak remains unexplained. The model prediction of response of alanine towards heavy charged particles encourages future use of the alanine detectors for dosimetry of mixed radiation fields.

  14. The Antiproton Depth Dose Curve Measured with Alanine Detectors

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, Johnny Witterseh; Palmans, Hugo

    2008-01-01

    In this paper we report on the measurement of the antiproton depth dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen et Olsen for conversion of calculated dose...... into response. A good agreement was observed between the measured and calculated relative effectiveness although a slight underestimation of the calculated values in the Bragg peak remains unexplained. The model prediction of response of alanine towards heavy charged particles encourages future use...... of the alanine detectors for dosimetry of mixed radiation fields....

  15. Genetics Home Reference: glycine encephalopathy

    Science.gov (United States)

    ... seizures. As they get older, many develop intellectual disability, abnormal movements, and behavioral problems. Other atypical types of glycine encephalopathy appear later in childhood or adulthood ...

  16. The VA, VCD, Raman and ROA spectra of tri-L-serine in aqueous solution

    DEFF Research Database (Denmark)

    Jürgensen, Vibeke Würtz; Jalkanen, Karl J.

    2006-01-01

    The structures of one conformer of the nonionic neutral and zwitterionic species of L-serinyl L-serinyl L-serine (SSS or tri-L-serine), together with its cationic and anionic species and the capped N-acetyl tri-L-serine N'-methylamide analog were optimized with density functional theory with the ......The structures of one conformer of the nonionic neutral and zwitterionic species of L-serinyl L-serinyl L-serine (SSS or tri-L-serine), together with its cationic and anionic species and the capped N-acetyl tri-L-serine N'-methylamide analog were optimized with density functional theory...

  17. The effect of point mutations on structure and mechanical properties of collagen-like fibril: A molecular dynamics study

    International Nuclear Information System (INIS)

    Marlowe, Ashley E.; Singh, Abhishek; Yingling, Yaroslava G.

    2012-01-01

    Understanding sequence dependent mechanical and structural properties of collagen fibrils is important for the development of artificial biomaterials for medical and nanotechnological applications. Moreover, point mutations are behind many collagen associated diseases, including Osteogenesis Imperfecta (OI). We conducted a combination of classical and steered atomistic molecular dynamics simulations to examine the effect of point mutations on structure and mechanical properties of short collagen fibrils which include mutations of glycine to alanine, aspartic acid, cysteine, and serine or mutations of hydroxyproline to arginine, asparagine, glutamine, and lysine. We found that all mutations disrupt structure and reduce strength of the collagen fibrils, which may affect the hierarchical packing of the fibrils. The glycine mutations were more detrimental to mechanical strength of the fibrils (WT > Ala > Ser > Cys > Asp) than that of hydroxyproline (WT > Arg > Gln > Asn > Lys). The clinical outcome for glycine mutations agrees well with the trend in reduction of fibril's tensile strength predicted by our simulations. Overall, our results suggest that the reduction in mechanical properties of collagen fibrils may be used to predict the clinical outcome of mutations. Highlights: ► All mutations disrupt structure and bonding pattern and reduce strength of the collagen fibrils. ► Gly based mutations are worst to mechanical integrity of fibrils than that of Hyp. ► Lys and Arg mutations most dramatically destabilize collagen fibril properties. ► Clinical outcome of mutations may be related to the reduced mechanical properties of fibrils.

  18. A High Sensitivity EPR Technique for Alanine Dosimetry (invited paper)

    International Nuclear Information System (INIS)

    Haskell, E.H.; Hayes, R.B.; Kenner, G.H.

    1998-01-01

    Uncertainties of ± 5 mGy were achieved in the measurement of alanine dosemeters using optimised EPR parameters, instrumentation, spectral manipulation and subtraction techniques. Modulation amplitude and microwave power were adjusted to combine resonances of two neighbouring alanine signals. Instrumental variations were minimised by combining and subtracting pre- and post-measurement spectra of the empty EPR tube. A spectrum of the native signal of non-dosed alanine was generated from a single batch of dosemeters and subtracted from spectra of the irradiated dosemeters, also from the same batch. Field alignment was adjusted with the use of an in-cavity Mn ++ standard. A constant rotation goniometer was used to eliminate anisotropies in the EPR tube and alanine samples. Finally, digital filters were applied to the resulting spectra. (author)

  19. Involvement of tyrosine residues, N-terminal amino acids, and beta-alanine in insect cuticular sclerotization.

    Science.gov (United States)

    Andersen, Svend Olav

    2007-09-01

    During sclerotization of insect cuticle the acyldopamines, N-acetyldopamine (NADA) and N-beta-alanyldopamine (NBAD), are oxidatively incorporated into the cuticular matrix, thereby hardening and stabilizing the material by forming crosslinks between the proteins in the cuticular matrix and by forming polymers filling the intermolecular spaces in the cuticle. Sclerotized cuticle from the locust, Schistocerca gregaria, and the beetle, Tenebrio molitor, was hydrolyzed in dilute hydrochloric acid, and from the hydrolysates some components presumably degradation products of cuticular crosslinks were isolated. In two of the components, the sidechain of 3,4-dihydroxyacetophenone was linked to the amino groups of glycine and beta-alanine, respectively, and in the third component to the phenolic group of tyrosine. These three compounds, glycino-dihydroxyacetophenone, beta-alanino-dihydroxyacetophenone, and O-tyrosino-dihydroxyacetophenone, as well as the previously reported compound, lysino-dihydroxyacetophenone [Andersen, S.O., Roepstorff, P., 2007. Aspects of cuticular sclerotization in the locust, Schistocerca gregaria, and the beetle, Tenebrio molitor. Insect Biochem. Mol. Biol. 37, 223-234], are suggested to be degradation products of cuticular crosslinks, in which amino acid residues formed linkages to both the alpha- and beta-positions of the sidechain of acyldopamines.

  20. First-principles study of the formation of glycine-producing radicals from common interstellar species

    Science.gov (United States)

    Sato, Akimasa; Kitazawa, Yuya; Ochi, Toshiro; Shoji, Mitsuo; Komatsu, Yu; Kayanuma, Megumi; Aikawa, Yuri; Umemura, Masayuki; Shigeta, Yasuteru

    2018-03-01

    Glycine, the simplest amino acid, has been intensively searched for in molecular clouds, and the comprehensive clarification of the formation path of interstellar glycine is now imperative. Among all the possible glycine formation pathways, we focused on the radical pathways revealed by Garrod (2013). In the present study, we have precisely investigated all the chemical reaction steps related to the glycine formation processes based on state-of-the-art density functional theory (DFT) calculations. We found that two reaction pathways require small activation barriers (ΔE‡ ≤ 7.75 kJ mol-1), which demonstrates the possibility of glycine formation even at low temperatures in interstellar space if the radical species are generated. The origin of carbon and nitrogen in the glycine backbone and their combination patterns are further discussed in relation to the formation mechanisms. According to the clarification of the atomic correspondence between glycine and its potential parental molecules, it is shown that the nitrogen and two carbons in the glycine can originate in three common interstellar molecules, methanol, hydrogen cyanide, and ammonia, and that the source molecules of glycine can be described by any of their combinations. The glycine formation processes can be categorized into six patterns. Finally, we discussed two other glycine formation pathways expected from the present DFT calculation results.

  1. Growth and antimicrobial studies of γ-glycine crystal grown using CuSO4

    Science.gov (United States)

    Vijayalakshmi, V.; Dhanasekaran, P.

    2018-05-01

    In the current work single crystals of pure and 1M of CuSO4-added glycine were grown by slow evaporation method and its optical and antimicrobial properties were studied. The Polymorph of glycine transforms from a-glycine to γ-glycine due to the incorporation of CuSO4 on glycine was affirmed by the PXRD and FTIR studies. The impact of CuSO4 on the antimicrobial action of the grown samples was deliberate by utilizing the agar diffusion method.

  2. Alanine scanning of the rabies virus glycoprotein antigenic site III using recombinant rabies virus: implication for post-exposure treatment.

    Science.gov (United States)

    Papaneri, Amy B; Wirblich, Christoph; Marissen, Wilfred E; Schnell, Matthias J

    2013-12-02

    The safety and availability of the human polyclonal sera that is currently utilized for post-exposure treatment (PET) of rabies virus (RABV) infection remain a concern. Recombinant monoclonal antibodies have been postulated as suitable alternatives by WHO. To this extent, CL184, the RABV human antibody combination comprising monoclonal antibodies (mAbs) CR57 and CR4098, has been developed and has delivered promising clinical data to support its use for RABV PET. For this fully human IgG1 cocktail, mAbs CR57 and CR4098 are produced in the PER.C6 human cell line and combined in equal amounts in the final product. During preclinical evaluation, CR57 was shown to bind to antigenic site I whereas CR4098 neutralization was influenced by a mutation of position 336 (N336) located within antigenic site III. Here, alanine scanning was used to analyze the influence of mutations within the potential binding site for CR4098, antigenic site III, in order to evaluate the possibility of mutated rabies viruses escaping neutralization. For this approach, twenty flanking amino acids (10 upstream and 10 downstream) of the RABV glycoprotein (G) asparagine (N336) were exchanged to alanine (or serine, if already alanine) by site-directed mutagenesis. Analysis of G expression revealed four of the twenty mutant Gs to be non-functional, as shown by their lack of cell surface expression, which is a requirement for the production of infectious RABV. Therefore, these mutants were excluded from further study. The remaining sixteen mutants were introduced in an infectious clone of RABV, and recombinant RABVs (rRABVs) were recovered and utilized for in vitro neutralization assays. All of the viruses were effectively neutralized by CR4098 as well as by CR57, indicating that single amino acid exchanges in this region does not affect the broad neutralizing capability of the CL184 mAb combination. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Studies on radiolysis of amino acids, 1

    International Nuclear Information System (INIS)

    Oku, Tadatake

    1977-01-01

    In order to elucidate the radiolysis of amino acid, peptide, protein and enzyme, the radiolytic mechanisms of neutral amino acids (glycine, L-alanine, L-valine, L-leucine, L-isoleucine, L-serine, and L-threonine) and acidic amino acids (L-aspartic acid, L-glutamic acid and DL-amino-n-adipic acid) were studied in the presence of air or in the atmosphere nitrogen. An aqueous solution of 1 mM. of each amino acid was sealed in a glass ampoule under air or nitrogen. Irradiation of amino acid solutions was carried out with γ-rays of 60 Co at doses of 4.4-2,640x10 3 rads. The amino acids and the radiolytic products formed were determined by ion-exchange chromatography. From the results of determining amino acids and the radiolytic products formed and their G-values, the radiolytic mechanisms of the amino acids were discussed. (auth.)

  4. Effective atomic numbers and electron densities of bacteriorhodopsin and its comprising amino acids in the energy range 1 keV–100 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Ahmadi, Morteza; Lunscher, Nolan [Waterloo Institute for Nanotechnology and Department of Systems Design Engineering, University of Waterloo, 200 University Ave., W., Waterloo, Ontario, Canada N2L 3G1 (Canada); Yeow, John T.W., E-mail: jyeow@uwaterloo.ca [Waterloo Institute for Nanotechnology and Department of Systems Design Engineering, University of Waterloo, 200 University Ave., W., Waterloo, Ontario, Canada N2L 3G1 (Canada)

    2013-04-01

    Recently, there has been an interest in fabrication of X-ray sensors based on bacteriorhodopsin, a proton pump protein in cell membrane of Halobacterium salinarium. Therefore, a better understanding of interaction of X-ray photons with bacteriorhodopsin is required. We use WinXCom program to calculate the mass attenuation coefficient of bacteriorhodopsin and its comprising amino acids for photon energies from 1 keV to 100 GeV. These amino acids include alanine, arginine, asparagine, aspartic acid, glutamine, glutamic acid, glycine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine, Asx1, Asx2, Glx1 and Glx2. We then use that data to calculate effective atomic number and electron densities for the same range of energy. We also emphasize on two ranges of energies (10–200 keV and 1–20 MeV) in which X-ray imaging and radiotherapy machines work.

  5. Development and cytotoxicity of Schiff base derivative as a fluorescence probe for the detection of L-Arginine

    Science.gov (United States)

    Shang, Xuefang; Li, Jie; Guo, Kerong; Ti, Tongyu; Wang, Tianyun; Zhang, Jinlian

    2017-04-01

    Inspired from biological counter parts, chemical modification of Schiff base derivatives with function groups may provide a highly efficient method to detect amino acids. Therefore, a fluorescent probe involving Schiff base and hydroxyl group has been designed and prepared, which showed high response and specificity for Arginine (Arg) among normal eighteen standard kinds of amino acids (Alanine, Valine, Leucine, Isoleucine, Methionine, Asparticacid, Glutamicacid, Arginine, Glycine, Serine, Threonine, Asparagine, Phenylalanine, Histidine, Tryptophan, Proline, Lysine, Glutamine, Tyrosine and Cysteine). Furthermore, theoretical investigation further illustrated the possible binding mode in the host-guest interaction and the roles of molecular frontier orbitals in molecular interplay. In addition, the synthesized fluorescent probe exhibited high binding ability for Arg and low cytotoxicity to MCF-7 cells over a concentration range of 0-200 μg mL-1 which can be also used as a biosensor for the Arg detection in vivo.

  6. Amino acid assisted dehalogenation of carbon tetrachloride by green rust

    DEFF Research Database (Denmark)

    Yin, Weizhao; Strobel, Bjarne W.; Hansen, Hans Chr. Bruun

    2017-01-01

    that reduce the formation of toxic by-products such as chloroform (CF). In this study, carbon tetrachloride (CT) dehalogenation by the chloride form of GR (GRCl) was tested in presence of glycine (GLY) and other selected amino acids. GLY, alanine (ALA) or serine (SER) all resulted in remarkable suppression...... of CF formation with only ~ 10% of CF recovery while sarcosine (SAR) showed insignificant effects. For two non-amino acid buffers, TRIS had little effect while HEPES resulted in a 40 times lower rate constant compared to experiments where no buffer was added. The FeII complexing properties of the amino...... acids and buffers caused variable extents of GRCl dissolution which was linearly correlated with CF suppression and dehalogenation rate. We hypothesize that the CF suppression seen for amino acids is caused by stabilization of carbene intermediates via the carbonyl group. Different effects on CF...

  7. Enantiomers of HA-966 (3-amino-1-hydroxypyrrolid-2-one) exhibit distinct central nervous system effects: (+)-HA-966 is a selective glycine/N-methyl-D-aspartate receptor antagonist, but (-)-HA-966 is a potent gamma-butyrolactone-like sedative

    International Nuclear Information System (INIS)

    Singh, L.; Donald, A.E.; Foster, A.C.; Hutson, P.H.; Iversen, L.L.; Iversen, S.D.; Kemp, J.A.; Leeson, P.D.; Marshall, G.R.; Oles, R.J.; Priestley, T.; Thorn, L.; Tricklebank, M.D.; Vass, C.A.; Williams, B.J.

    1990-01-01

    The antagonist effect of ±-3-amino-1-hydroxypyrrolid-2-one (HA-966) at the N-methyl-D-aspartate (NMDA) receptor occurs through a selective interaction with the glycine modulatory site within the receptor complex. When the enantiomers of ±-HA-966 were resolved, the (R)-(+)-enantiomer was found to be a selective glycine/NMDA receptor antagonist, a property that accounts for its anticonvulsant activity in vivo. In contrast, the (S)-(-)-enantiomer was only weakly active as an NMDA-receptor antagonist, but nevertheless it possessed a marked sedative and muscle relaxant action in vivo. In radioligand binding experiments, (+)-HA-966 inhibited strychnine-insensitive [ 3 H]glycine binding to rat cerebral cortex synaptic membranes with an IC 50 of 12.5 μM, whereas (-)-HA-966 had an IC 50 value of 339 μM. In mice, (+)-HA-966 antagonized sound and N-methyl-DL-aspartic acid (NMDLA)-induced seizures. The coadministration of D-serine dose-dependently antagonized the anticonvulsant effect of a submaximal dose of (+)-HA-966 against NMDLA-induced seizures. The sedative/ataxic effect of racemic HA-966 was mainly attributable to the (-)-enantiomer. It is suggested that, as in the case of the sedative γ-butyrolactone, disruption of striatal dopaminergic mechanisms may be responsible for this action

  8. Convergent synthesis of a deuterium-labeled serine dipeptide lipid for analysis of biological samples.

    Science.gov (United States)

    Dietz, Christopher; Clark, Robert B; Nichols, Frank C; Smith, Michael B

    2017-05-30

    Bacterial serine dipeptide lipids are known to promote inflammatory processes and are detected in human tissues associated with periodontal disease or atherosclerosis. Accurate quantification of bacterial serine lipid, specifically lipid 654 [((S)-15-methyl-3-((13-methyltetradecanoyl)oxy)hexadecanoyl)glycyl-l-serine, (3S)-l-serine] isolated from Porphyromonas gingivalis, in biological samples requires the preparation of a stable isotope internal standard for sample supplementation and subsequent mass spectrometric analysis. This report describes the convergent synthesis of a deuterium-substituted serine dipeptide lipid, which is an isotopically labeled homologue that represents a dominant form of serine dipeptide lipid recovered in bacteria. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Determination of the dose of traffic in HDR brachytherapy with ALANINE/R PE technique

    International Nuclear Information System (INIS)

    Guzman Calcina, C. S.; Chen, F.; Almeida, A. de; Baffa, O.

    2001-01-01

    It determines, experimentally, the dose of traffic in brachytherapy for High Dose Rate (HDR), using for the first-time the Electronic Paramagnetic Resonance (EPR) technique with alanine detectors. The value obtained is the published next to obtained using lithium fluoride thermoluminescent dosimeters [es

  10. Importance of intrahepatic mechanisms to gluconeogenesis from alanine during exercise and recovery

    International Nuclear Information System (INIS)

    Wasserman, D.H.; Williams, P.E.; Lacy, D.B.; Green, D.R.; Cherrington, A.D.

    1988-01-01

    These studies were performed to assess the importance of intrahepatic mechanisms to gluconeogenesis in the dog during 150 min of treadmill exercise and 90 min of recovery. Sampling catheters were implanted in an artery and portal and hepatic veins 16 days before experimentation. Infusions of [U- 14 C]alanine, [3- 3 H]glucose, and indocyanine green were used to assess gluconeogenesis. During exercise, a decline in arterial and portal vein plasma alanine and in hepatic blood flow led to a decrease in hepatic alanine delivery. During recovery, hepatic blood flow was restored to basal, causing an increase in hepatic alanine delivery beyond exercise rates but still below resting rates. Hepatic fractional alanine extraction increased from 0.26 +/- 0.02 at rest to 0.64 +/- 0.03 during exercise and remained elevated during recovery. Net hepatic alanine uptake was 2.5 +/- 0.2 mumol.kg-1.min-1 at rest and remained unchanged during exercise but was increased during recovery. The conversion rate of [ 14 C]alanine to glucose had increased by 248 +/- 38% by 150 min of exercise and had increased further during recovery. The efficiency with which alanine was channeled into glucose in the liver was accelerated to a rate of 338 +/- 55% above basal by 150 min of exercise but declined slightly during recovery. In conclusion, 1) gluconeogenesis from alanine is accelerated during exercise, due to an increase in the hepatic fractional extraction of the amino acid and through intrahepatic mechanisms that more efficiently channel it into glucose

  11. Mitochondrial defects associated with β-alanine toxicity: relevance to hyper-beta-alaninemia

    Science.gov (United States)

    Shetewy, Aza; Shimada-Takaura, Kayoko; Warner, Danielle; Jong, Chian Ju; Mehdi, Abu-Bakr Al; Alexeyev, Mikhail; Takahashi, Kyoko; Schaffer, Stephen W.

    2016-01-01

    Hyper-beta-alaninemia is a rare metabolic condition that results in elevated plasma and urinary β-alanine levels and is characterized by neurotoxicity, hypotonia, and respiratory distress. It has been proposed that at least some of the symptoms are caused by oxidative stress; however, only limited information is available on the mechanism of reactive oxygen species generation. The present study examines the hypothesis that β-alanine reduces cellular levels of taurine, which are required for normal respiratory chain function; cellular taurine depletion is known to reduce respiratory function and elevate mitochondrial superoxide generation. To test the taurine hypothesis, isolated neonatal rat cardiomyocytes and mouse embryonic fibroblasts were incubated with medium lacking or containing β-alanine. β-alanine treatment led to mitochondrial superoxide accumulation in conjunction with a decrease in oxygen consumption. The defect in β-alanine-mediated respiratory function was detected in permeabilized cells exposed to glutamate/malate but not in cells utilizing succinate, suggesting that β-alanine leads to impaired complex I activity. Taurine treatment limited mitochondrial superoxide generation, supporting a role for taurine in maintaining complex I activity. Also affected by taurine is mitochondrial morphology, as β-alanine-treated fibroblasts undergo fragmentation, a sign of unhealthy mitochondria that is reversed by taurine treatment. If left unaltered, β-alanine-treated fibroblasts also undergo mitochondrial apoptosis, as evidenced by activation of caspases 3 and 9 and the initiation of the mitochondrial permeability transition. Together, these data show that β-alanine mediates changes that reduce ATP generation and enhance oxidative stress, factors that contribute to heart failure. PMID:27023909

  12. The features of radiation damages in L-alanine crystals

    International Nuclear Information System (INIS)

    Zaitov, V.R.; Onischuk, V.A.

    1996-01-01

    The method of the ESR alanine dosimetry has appeared the most convenient one for measurement of radiation dose in the range 1-10 6 Gy. Its peculiarities are the wide dose range, the high accuracy, the absence fading at room temperature, the possibility of many times repeated measurements as dosemeter accumulates dose, the simplicity of measurements. Because of this performance ESR alanine dosimetry technique can be applied to continuous monitoring radiation doses absorbed by materials on nuclear power stations as well as of dose fields and restoration doses after an accident situation. In order to determine accurately the absorbed dose in an accident on background of accumulated dose for previous period, it is necessary to the utmost increase the accuracy of dosimetry system. For this reason it is necessary to know how the properties of free radicals which formings in irradiated L-alanine are displayed in signal ESR. With the purpose to detect the structure of the free radicals the ESR spectra the L-alanine and L-alanine-d 3 single crystals were studied. The samples were grown by slow evaporation of the saturated aqueous solution. For obtain the L-alanine-d 3 the three-divisible recrystallization in heavy water had been used. The samples were irradiated with 60 Co at room temperature and in liquid nitrogen. The irradiation doses were 10 kGy and dose rate was 8,3 Gy/s. To increase the resolution of the ESR spectra hyperfine structure the second derivative for the absorption curve was registered. The measurements were conducted in X-range at temperatures 77-430 K. (author)

  13. Nitrile-synthesizing enzyme: Screening, purification and characterization.

    Science.gov (United States)

    Kumano, Takuto; Suzuki, Takahisa; Shimizu, Sakayu; Kobayashi, Michihiko

    2016-09-12

    Cyanide is known as a toxic compound for almost all living organisms. We have searched for cyanide-resistant bacteria from the soil and stock culture collection of our laboratory, and have found the existence of a lot of microorganisms grown on culture media containing 10 mM potassium cyanide. Almost all of these cyanide-resistant bacteria were found to show β-cyano-L-alanine (β-CNAla) synthetic activity. β-CNAla synthase is known to catalyze nitrile synthesis: the formation of β-CNAla from potassium cyanide and O-acetyl-L-serine or L-cysteine. We found that some microorganisms were able to detoxify cyanide using O-methyl-DL-serine, O-phospho-L-serine and β-chloro-DL-alanine. In addition, we purified β-CNAla synthase from Pseudomonas ovalis No. 111 in nine steps, and characterized the purified enzyme. This enzyme has a molecular mass of 60,000 and appears to consist of two identical subunits. The purified enzyme exhibits a maximum activity at pH 8.5-9.0 at an optimal temperature of 40-50°C. The enzyme is specific for O-acetyl-L-serine and β-chloro-DL-alanine. The Km value for O-acetyl-L-serine is 10.0 mM and Vmax value is 3.57 μmol/min/mg.

  14. Asymmetric adsorption of alanine by quartz powder from ethanol solution

    Energy Technology Data Exchange (ETDEWEB)

    Furuyama, Shozo; Sawada, Michio; Hachiya, Kinji; Morimoto, Tetsuo (Okayama Univ. (Japan). Faculty of Science)

    1982-11-01

    The asymmetric adsorption of the racemic alanine by the optically active quartz from ethanol solution at 8/sup 0/C was studied by the /sup 14/C-tracer method and the newly developed /sup 14/C-tracer ninhydrin-colorimetry combination method. The preferential adsorption of L-alanine by levorotatory quartz (l-quartz) and D-alanine by dextrorotatory quartz (d-quartz) was confirmed. The asymmetric adsorptivity (Asub(s)) falls in the range of 1.1 - 1.3, which is comparable with the value determined at - 80/sup 0/C in the previous paper. The effects of water content in the ethanol solution and of the adsorption temperature upon the adsorption affinity of alanine to quartz were also measured. The cause for the asymmetric adsorption is discussed from the crystallographic point of view.

  15. Structure-activity relationships of strychnine analogues at glycine receptors

    DEFF Research Database (Denmark)

    Mohsen, A.M.Y.; Heller, Eberhard; Holzgrabe, Ulrike

    2014-01-01

    Nine strychnine derivatives including neostrychnine, strychnidine, isostrychnine, 21,22-dihydro-21-hydroxy-22-oxo-strychnine, and several hydrogenated analogs were synthesized, and their antagonistic activities at human α1 and α1β glycine receptors were evaluated. Isostrychnine has shown the best...... pharmacological profile exhibiting an IC50 value of 1.6 μM at α1 glycine receptors and 3.7-fold preference towards the α1 subtype. SAR Analysis indicates that the lactam moiety and the C(21)[DOUBLE BOND]C(22) bond in strychnine are essential structural features for its high antagonistic potency at glycine...

  16. Functional and biochemical analysis of Chlamydia trachomatis MurC, an enzyme displaying UDP-N-acetylmuramate:amino acid ligase activity.

    Science.gov (United States)

    Hesse, Lars; Bostock, Julieanne; Dementin, Sebastien; Blanot, Didier; Mengin-Lecreulx, Dominique; Chopra, Ian

    2003-11-01

    Chlamydiae are unusual obligate intracellular bacteria that cause serious infections in humans. Chlamydiae contain genes that appear to encode products with peptidoglycan biosynthetic activity. The organisms are also susceptible to antibiotics that inhibit peptidoglycan synthesis. However, chlamydiae do not synthesize detectable peptidoglycan. The paradox created by these observations is known as the chlamydial anomaly. The MurC enzyme of chlamydiae, which is synthesized as a bifunctional MurC-Ddl product, is expected to possess UDP-N-acetylmuramate (UDP-MurNAc):L-alanine ligase activity. In this paper we demonstrate that the MurC domain of the Chlamydia trachomatis bifunctional protein is functionally expressed in Escherichia coli, since it complements a conditional lethal E. coli mutant possessing a temperature-sensitive lesion in MurC. The recombinant MurC domain was overexpressed in and purified from E. coli. It displayed in vitro ATP-dependent UDP-MurNAc:L-alanine ligase activity, with a pH optimum of 8.0 and dependence upon magnesium ions (optimum concentration, 20 mM). Its substrate specificity was studied with three amino acids (L-alanine, L-serine, and glycine); comparable Vmax/Km values were obtained. Our results are consistent with the synthesis of a muramic acid-containing polymer in chlamydiae with UDP-MurNAc-pentapeptide as a precursor molecule. However, due to the lack of specificity of MurC activity in vitro, it is not obvious which amino acid is present in the first position of the pentapeptide.

  17. The purine-utilizing bacterium Clostridium acidurici 9a: a genome-guided metabolic reconsideration.

    Directory of Open Access Journals (Sweden)

    Katrin Hartwich

    Full Text Available Clostridium acidurici is an anaerobic, homoacetogenic bacterium, which is able to use purines such as uric acid as sole carbon, nitrogen, and energy source. Together with the two other known purinolytic clostridia C. cylindrosporum and C. purinilyticum, C. acidurici serves as a model organism for investigation of purine fermentation. Here, we present the first complete sequence and analysis of a genome derived from a purinolytic Clostridium. The genome of C. acidurici 9a consists of one chromosome (3,105,335 bp and one small circular plasmid (2,913 bp. The lack of candidate genes encoding glycine reductase indicates that C. acidurici 9a uses the energetically less favorable glycine-serine-pyruvate pathway for glycine degradation. In accordance with the specialized lifestyle and the corresponding narrow substrate spectrum of C. acidurici 9a, the number of genes involved in carbohydrate transport and metabolism is significantly lower than in other clostridia such as C. acetobutylicum, C. saccharolyticum, and C. beijerinckii. The only amino acid that can be degraded by C. acidurici is glycine but growth on glycine only occurs in the presence of a fermentable purine. Nevertheless, the addition of glycine resulted in increased transcription levels of genes encoding enzymes involved in the glycine-serine-pyruvate pathway such as serine hydroxymethyltransferase and acetate kinase, whereas the transcription levels of formate dehydrogenase-encoding genes decreased. Sugars could not be utilized by C. acidurici but the full genetic repertoire for glycolysis was detected. In addition, genes encoding enzymes that mediate resistance against several antimicrobials and metals were identified. High resistance of C. acidurici towards bacitracin, acriflavine and azaleucine was experimentally confirmed.

  18. The purine-utilizing bacterium Clostridium acidurici 9a: a genome-guided metabolic reconsideration.

    Science.gov (United States)

    Hartwich, Katrin; Poehlein, Anja; Daniel, Rolf

    2012-01-01

    Clostridium acidurici is an anaerobic, homoacetogenic bacterium, which is able to use purines such as uric acid as sole carbon, nitrogen, and energy source. Together with the two other known purinolytic clostridia C. cylindrosporum and C. purinilyticum, C. acidurici serves as a model organism for investigation of purine fermentation. Here, we present the first complete sequence and analysis of a genome derived from a purinolytic Clostridium. The genome of C. acidurici 9a consists of one chromosome (3,105,335 bp) and one small circular plasmid (2,913 bp). The lack of candidate genes encoding glycine reductase indicates that C. acidurici 9a uses the energetically less favorable glycine-serine-pyruvate pathway for glycine degradation. In accordance with the specialized lifestyle and the corresponding narrow substrate spectrum of C. acidurici 9a, the number of genes involved in carbohydrate transport and metabolism is significantly lower than in other clostridia such as C. acetobutylicum, C. saccharolyticum, and C. beijerinckii. The only amino acid that can be degraded by C. acidurici is glycine but growth on glycine only occurs in the presence of a fermentable purine. Nevertheless, the addition of glycine resulted in increased transcription levels of genes encoding enzymes involved in the glycine-serine-pyruvate pathway such as serine hydroxymethyltransferase and acetate kinase, whereas the transcription levels of formate dehydrogenase-encoding genes decreased. Sugars could not be utilized by C. acidurici but the full genetic repertoire for glycolysis was detected. In addition, genes encoding enzymes that mediate resistance against several antimicrobials and metals were identified. High resistance of C. acidurici towards bacitracin, acriflavine and azaleucine was experimentally confirmed.

  19. A new synthesis of [3-11C]pyruvic acid using alanine racemase

    International Nuclear Information System (INIS)

    Ikemoto, M.; Okamoto, E.; Sasaki, M.; Haradahira, T.; Omura, H.; Furuya, Y.; Suzuki, K.; Watanabe, Y.

    1998-01-01

    The synthesis of [3- 11 C]pyruvic acid was attempted by two reaction systems (A: alanine racemase and D-amino acid oxidase, B: alanine racemase and L-alanine dehydrogenase) utilizing a new thermostable enzyme, alanine racemase. Conversion rates from D,L-[3- 11 C]alanine to [3- 11 C]pyruvic acid were almost 100% in both methods. Similar results were obtained with immobilized enzymes packed in a single column. Furthermore, the same column could be used repeatedly without a remarkable decrease of the [3- 11 C]pyruvic acid yield. Various matrices were tested for the immobilizing enzyme, and Aminopropyl-CPG was concluded to be the most suitable since the loss of the enzyme activity was the least in the studied matrices

  20. Uses of polymer-alanine film/ESR dosimeters in dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Xie Liqing; Zhang Yinfeng; Dai Jinxian; Lu Ting; Chen Ruyi; Yang Hua

    1993-01-01

    Alanine ESR dosimetry is a reliable method, used in a various fields of ionizing radiation. The polymer-alanine film/ESR dosimeters of 0.3 -0.4 mm thickness were prepared and their dosimetric properties were studied for 60 Co γ photons and 3 - 5 MeV electrons in the dose range from 20 Gy to 100 kGy. The results show that under normal conditions the alanine calibration curves are linear in the dose range from 100 Gy to 10kGy. The dose profiles at the electron radiation field were measured with the film alanine dosimeters. The polymer-alanine film dosimeters were used for ion implantation of 400 keV ion implantor. Their dose response and energy dependence were investigated initially. (Author)

  1. A weak link in metabolism: the metabolic capacity for glycine ...

    Indian Academy of Sciences (India)

    Prakash

    2009-12-03

    Dec 3, 2009 ... glyoxylate, threonine and trimethyllysine (carnitine synthesis), most of them ...... Participation of glycine in porphyrin biosynthesis. Eight glycine ...... normal and streptozotocin-induced diabetic rats; J. Dent. Res. 63 23–27.

  2. Thin layer alanine dosimeter with optical spectrophotometric evaluation

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    2000-01-01

    Experience in the high dose dosimetry of gamma radiation, gathered in our group from the sixties till now, allows to express the opinion, that techniques applied are adequate to solve problems. It can be confirmed by the fact that 60% of laboratories participating in the international comparison during the duration of the contract obtained satisfactory results. Adaptation of these methods, in particular of the alanine-ESR dosimetry to highly inhomogeneous fields of EB gives poor results, as it has been shown on thin films of the alanine/polymer composite. However, the applications of these films give excellent results if the concentration of the radical CH 3 C·H CO 2 - is measured by diffuse reflection spectrophotometry, which tolerates poor transparency of the composite and is insensitive to the orientation of crystals of alanine in thin films, what is disqualifying the ESR measurements. The development of thin-film dosimeters for EB processing was possible due to new developments in solid state radiation chemistry. The research has revealed some unsolved questions, e.g. of the high temperature coefficient of alanine based dosimeters, of the role of the size of spurs and the necessity to adapt dosimetry to the energy spectrum of electrons, because every type of accelerators differs in that respect. (author)

  3. Alanine turnover in the postabsorptive state and during parenteral hyperalimentation before and after surgery

    NARCIS (Netherlands)

    Sauerwein, H. P.; Michels, R. P.; Cejka, V.

    1981-01-01

    Influence of total parenteral nutrition and operation on alanine turnover and venous alanine concentration was determined in 5 patients with stomach carcinoma using single technique of U-14C alanine. Every patient served at his own control. In the postabsorptive state alanine turnover was 1.63 +/-

  4. Site-specific DNA Inversion by Serine Recombinases

    Science.gov (United States)

    2015-01-01

    Reversible site-specific DNA inversion reactions are widely distributed in bacteria and their viruses. They control a range of biological reactions that most often involve alterations of molecules on the surface of cells or phage. These programmed DNA rearrangements usually occur at a low frequency, thereby preadapting a small subset of the population to a change in environmental conditions, or in the case of phages, an expanded host range. A dedicated recombinase, sometimes with the aid of additional regulatory or DNA architectural proteins, catalyzes the inversion of DNA. RecA or other components of the general recombination-repair machinery are not involved. This chapter discusses site-specific DNA inversion reactions mediated by the serine recombinase family of enzymes and focuses on the extensively studied serine DNA invertases that are stringently controlled by the Fis-bound enhancer regulatory system. The first section summarizes biological features and general properties of inversion reactions by the Fis/enhancer-dependent serine invertases and the recently described serine DNA invertases in Bacteroides. Mechanistic studies of reactions catalyzed by the Hin and Gin invertases are then discussed in more depth, particularly with regards to recent advances in our understanding of the function of the Fis/enhancer regulatory system, the assembly of the active recombination complex (invertasome) containing the Fis/enhancer, and the process of DNA strand exchange by rotation of synapsed subunit pairs within the invertasome. The role of DNA topological forces that function in concert with the Fis/enhancer controlling element in specifying the overwhelming bias for DNA inversion over deletion and intermolecular recombination is emphasized. PMID:25844275

  5. New L-Serine Derivative Ligands as Cocatalysts for Diels-Alder Reaction

    Science.gov (United States)

    Sousa, Carlos A. D.; Rodríguez-Borges, José E.; Freire, Cristina

    2013-01-01

    New L-serine derivative ligands were prepared and tested as cocatalyst in the Diels-Alder reactions between cyclopentadiene (CPD) and methyl acrylate, in the presence of several Lewis acids. The catalytic potential of the in situ formed complexes was evaluated based on the reaction yield. Bidentate serine ligands showed good ability to coordinate medium strength Lewis acids, thus boosting their catalytic activity. The synthesis of the L-serine ligands proved to be highly efficient and straightforward. PMID:24383009

  6. Serine integrase chimeras with activity in E. coli and HeLa cells

    Directory of Open Access Journals (Sweden)

    Alfonso P. Farruggio

    2014-09-01

    Full Text Available In recent years, application of serine integrases for genomic engineering has increased in popularity. The factor-independence and unidirectionality of these large serine recombinases makes them well suited for reactions such as site-directed vector integration and cassette exchange in a wide variety of organisms. In order to generate information that might be useful for altering the specificity of serine integrases and to improve their efficiency, we tested a hybridization strategy that has been successful with several small serine recombinases. We created chimeras derived from three characterized members of the serine integrase family, phiC31, phiBT1, and TG1 integrases, by joining their amino- and carboxy-terminal portions. We found that several phiBT1-phiC31 (BC and phiC31-TG1 (CT hybrid integrases are active in E. coli. BC chimeras function on native att-sites and on att-sites that are hybrids between those of the two donor enzymes, while CT chimeras only act on the latter att-sites. A BC hybrid, BC{−1}, was also active in human HeLa cells. Our work is the first to demonstrate chimeric serine integrase activity. This analysis sheds light on integrase structure and function, and establishes a potentially tractable means to probe the specificity of the thousands of putative large serine recombinases that have been revealed by bioinformatics studies.

  7. Synthesis of water soluble glycine capped silver nanoparticles and their surface selective interaction

    International Nuclear Information System (INIS)

    Agasti, Nityananda; Singh, Vinay K.; Kaushik, N.K.

    2015-01-01

    Highlights: • Synthesis of water soluble silver nanoparticles at ambient reaction conditions. • Glycine as stabilizing agent for silver nanoparticles. • Surface selective interaction of glycine with silver nanoparticles. • Glycine concentration influences crystalinity and optical property of silver nanoparticles. - Abstract: Synthesis of biocompatible metal nanoparticles has been an area of significant interest because of their wide range of applications. In the present study, we have successfully synthesized water soluble silver nanoparticles assisted by small amino acid glycine. The method is primarily based on reduction of AgNO 3 with NaBH 4 in aqueous solution under atmospheric air in the presence of glycine. UV–vis spectroscopy, transmission electron microscopy (TEM), X–ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG) and differential thermal analysis (DTA) techniques used for characterization of resulting silver nanoparticles demonstrated that, glycine is an effective capping agent to stabilize silver nanoparticles. Surface selective interaction of glycine on (1 1 1) face of silver nanoparticles has been investigated. The optical property and crystalline behavior of silver nanoparticles were found to be sensitive to concentration of glycine. X–ray diffraction studies ascertained the phase specific interaction of glycine on silver nanoparticles. Silver nanoparticles synthesized were of diameter 60 nm. We thus demonstrated an efficient synthetic method for synthesis of water soluble silver nanoparticles capped by amino acid under mild reaction conditions with excellent reproducibility

  8. Role of L-alanine for redox self-sufficient amination of alcohols.

    Science.gov (United States)

    Klatte, Stephanie; Wendisch, Volker F

    2015-01-23

    In white biotechnology biocatalysis represents a key technology for chemical functionalization of non-natural compounds. The plasmid-born overproduction of an alcohol dehydrogenase, an L-alanine-dependent transaminase and an alanine dehydrogenase allows for redox self-sufficient amination of alcohols in whole cell biotransformation. Here, conditions to optimize the whole cell biocatalyst presented in (Bioorg Med Chem 22:5578-5585, 2014), and the role of L-alanine for efficient amine functionalization of 1,10-decanediol to 1,10-diaminodecane were analyzed. The enzymes of the cascade for amine functionalization of alcohols were characterized in vitro to find optimal conditions for an efficient process. Transaminase from Chromobacterium violaceum, TaCv, showed three-fold higher catalytic efficiency than transaminase from Vibrio fluvialis, TaVf, and improved production at 37°C. At 42°C, TaCv was more active, which matched thermostable alcohol dehydrogenase and alanine dehydrogenase and improved the 1,10-diaminodecane production rate four-fold. To study the role of L-alanine in the whole cell biotransformation, the L-alanine concentration was varied and 1,10.diaminodecane formation tested with constant 10 mM 1,10- decanediol and 100 mM NH4Cl. Only 5.6% diamine product were observed without added L-alanine. L-alanine concentrations equimolar to that of the alcohol enabled for 94% product formation but higher L-alanine concentrations allowed for 100% product formation. L-alanine was consumed by the E. coli biocatalyst, presumably due to pyruvate catabolism since up to 16 mM acetate accumulated. Biotransformation employing E. coli strain YYC202/pTrc99a-ald-adh-ta Cv, which is unable to catabolize pyruvate, resulted in conversion with a selectivity of 42 mol-%. Biotransformation with E. coli strains only lacking pyruvate oxidase PoxB showed similar reduced amination of 1,10-decanediol indicating that oxidative decarboxylation of pyruvate to acetate by PoxB is primarily

  9. Preparation of alanine/ESR dosimeter using different binder of polymer blend

    International Nuclear Information System (INIS)

    Razzak, M.T.; Sudiro, Sutjipto; Sudradjat, Adjat; Waskito, Ashar; Djamili, M.F.

    1995-01-01

    Different composition of polymer blend of low density polyethylene (PE) and polystyrene (PS) have been studied to be used as a binder for the preparation of Alanine/ESR dosimeter. The polymer binder and Alanine powder were blended in Laboplastomil Mixer at 140 o C and then it was pressed into a plastic film of 0.50 mm thickness. The film was cut into sample size of 250 mm x 2.5 mm and irradiated by gamma rays from a cobalt-60 source at different dose and dose rate. It was found that a blend of Alanine, PS and PE in composition of 60:30:10 is appropriate to prepare the Alanine/ESR dosimeter. (author)

  10. Dynamics of solid alanine by means of nuclear magnetic resonance relaxometry

    Science.gov (United States)

    Kubica-Misztal, A.; Rochowski, P.; Florek-Wojciechowska, M.; Kruk, D.

    2017-04-01

    1H nuclear magnetic resonance relaxometry was applied to investigate the dynamics of l-alanine in the solid phase (powder). The experimental studies were carried out in a very broad frequency range, covering four orders of magnitude—from 4 kHz to 40 MHz (referring to the 1H resonance frequency) in order to probe motional processes of much different time scales by a single experiment. To get access to the dynamics of different proton groups of alanine, the 1H spin-lattice relaxation measurements were performed for non-deuterated and partially deuterated alanine. The experiments were carried out in the temperature range of 293 K-370 K (non-deuterated alanine) and 318 K-370 K (partially deuterated alanine). As a result of a thorough theoretical analysis of the extensive set of experimental results, three motional processes occurring on different time scales are identified and quantitatively described. The slowest process occurs on a time scale of μs and it is attributed to the collective dynamics of a 3D hydrogen bond network of alanine, while the intermediate, attributed to the dynamics of the NH3 group, corresponds to the range of tenths of ns. The fast process describes the rotation of the CH3 group.

  11. Characterization of the l-alanine exporter AlaE of Escherichia coli and its potential role in protecting cells from a toxic-level accumulation of l-alanine and its derivatives

    OpenAIRE

    Kim, Seryoung; Ihara, Kohei; Katsube, Satoshi; Hori, Hatsuhiro; Ando, Tasuke; Isogai, Emiko; Yoneyama, Hiroshi

    2015-01-01

    We previously reported that the alaE gene of Escherichia coli encodes the l-alanine exporter AlaE. The objective of this study was to elucidate the mechanism of the AlaE exporter. The minimum inhibitory concentration of l-alanine and l-alanyl-l-alanine in alaE-deficient l-alanine-nonmetabolizing cells MLA301ΔalaE was 4- and >4000-fold lower, respectively, than in the alaE-positive parent cells MLA301, suggesting that AlaE functions as an efflux pump to avoid a toxic-level accumulation of intr...

  12. Sensitivity comparison of two L-alanine doped blends to different photon energies

    International Nuclear Information System (INIS)

    Chen, Felipe; Vega Ramirez, Jose; Nicolucci, Patricia; Baffa, Oswaldo

    2008-01-01

    Full text: Blends of L-alanine (85% weight proportion) with KI (10%) and with PbI 2 (10%), these last two compounds acting as dopants, and with PVA (5%) acting as binder, were prepared in water at 80 C degrees. A blend of pure L-alanine (95%) with PVA (5%) was also prepared. The three blends were irradiated with photon beams of different energies (120 kV, 60 Co and 10 MV) with a unique dose of 30 Gy to compare their sensitivities for those three energies. EPR spectra of the three irradiated blends were recorded in a K-Band spectrometer (24 GHz) taking aliquots of about 4 mg for each blend. The energy sensitivity of a blend was defined as the peak-to-peak amplitude of its EPR spectrum central line. For the 60 Co energy (1.25 MeV) the blends presented practically the same sensitivity indicating that the presence of the dopants does not affect the sensitivity of L-alanine. For 10 MV X-rays there was an increment (around 20% - 30 %) in sensitivity for the two L-alanine doped blends compared with the pure L-alanine blend (not doped). In the case of 120 kV X-rays, the blends ala+KI and ala+PbI 2 showed an increment of 10 and 20 times, respectively, more sensitivity than the pure L-alanine blend. It is concluded that the dopants KI and PbI 2 produce a great enhance of the L-alanine sensitivity to low-energy photons. For the same dopant's content (10%) in the blend, PbI 2 showed a better performance. These results encourage us to try to enhance the sensitivity of L-alanine even more increasing the dopant's content in the blend. Application of these L-alanine doped blends in the dosimetry in diagnostic radiology could be possible. (author)

  13. Molecular characterisation of a recombinant bovine glycine N-acyltransferase / Christoffel Petrus Stephanus Badenhorst

    OpenAIRE

    Badenhorst, Christoffel Petrus Stephanus

    2010-01-01

    Conjugation of glycine to organic acids is an important detoxification mechanism. Metabolites of aspirin and industrial solvents, benzoic acid found in plant material and many endogenous metabolites are detoxified by conjugation to glycine. The enzyme responsible for glycine conjugation, glycine N-acyltransferase (GL YAT), is investigated in this study. The enzyme is also important for the management of organic acidemias which are inherited metabolic diseases. However, not all ...

  14. Postirradiation effects in alanine dosimeter probes of two different suppliers

    International Nuclear Information System (INIS)

    Anton, Mathias

    2008-01-01

    The measurand relevant for the dosimetry for radiation therapy is the absorbed dose to water, D W . The Physikalisch-Technische Bundesanstalt (PTB) is establishing a secondary standard for D W for high-energy photon and electron radiation based on electron spin resonance (ESR) of the amino acid alanine. For practical applications, like, for example, intercomparison measurements using the ESR/alanine dosimetry system, the temporal evolution of the ESR signal of irradiated probes is an important issue. This postirradiation behaviour is investigated for alanine pellets of two different suppliers for different storage conditions. The influence of the storage conditions on the temporal evolution may be dependent on the type of probes used. The measurement and analysis method developed at the PTB is able to circumvent the apparent difficulties in the case of alanine/paraffin probes. Care has to be taken in case this method cannot be applied

  15. Interaction of Heterodera glycines and Glomus mosseae on Soybean.

    Science.gov (United States)

    Todd, T C; Winkler, H E; Wilson, G W

    2001-12-01

    The effects of the arbuscular mycorrhizal (AM) fungus Glomus mosseae on Heterodera glycines-soybean interactions were investigated in greenhouse experiments. Mycorrhizal and nonmycorrhizal soybean cultivars that were either resistant or susceptible to H. glycines were exposed to initial nematode population densities (Pi) of 0, 100, 1,000, or 10,000 eggs and infective juveniles. Soybean growth, nematode reproduction, and AM fungal colonization were determined after 35 (experiment I) and 83 (experiment II) days. Soybean shoot and root weights were reduced an average 29% across H. glycines Pi but were 36% greater overall in the presence of G. mosseae. Analyses of variance indicated that root colonization and stimulation of soybean growth by G. mosseae were inhibited at high H. glycines Pi, while the combined effects of the nematode and fungus on soybean growth were best described as additive in linear regression models. No evidence for increased nematode tolerance of mycorrhizal soybean plants was observed. Nematode population densities and reproduction were lower on a nematode-resistant soybean cultivar than on a susceptible cultivar, but reproduction was comparable on mycorrhizal and nonmycorrhizal plants. Root colonization by G. mosseae was reduced at high nematode Pi. The results suggest that nematode antagonism to the mycorrhizal symbiosis is a more likely consequence of interactions between H. glycines and AM fungi on soybean than is nematode suppression by the fungus.

  16. Nitrogen functionality of glucose-glycine condensate; Glucose to glycine tono shukugo hanno (shukugobutsuchu no chisso kagobutsu no keitai bunseki)

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, C.; Yoshioka, T.; Komano, T.; Mashimo, K.; Wainai, T. [Nihon University, Tokyo (Japan). College of Science and Technology; Sugimoto, Y.; : Miki, Y. [National Institute of Materials and Chemical Research, Tsukuba (Japan)

    1996-10-28

    In order to clarify a humification process in the early stage of coalification, the nitrogen functionality of prepared glucose-glycine condensate was studied experimentally. In experiment, the condensate was prepared by heating the mixture of glucose, glycine and water in a autoclave at 130{degree}C for 50 hours, and furthermore heating the produced solid material in water at 300{degree}C. After the condensate was hydrocracked, the fraction, condensate and hydrocracking residue were analyzed by elementary analyzer, {sup 13}C-NMR, XPS, FT-IR, capillary GC-FID/NPD and GC-MS. As a result, the glucose-glycine condensate could be arranged on the basis of three types of nitrogen such as pyridine, pyrrole and quaternary amine type. Pyridine type nitrogen increased, while quaternary amine type one decreased with an increase in heating treatment temperature. Rich pyrrole type nitrogen and poor pyridine type one were found in light nitrogen compounds in hydrocracked products. 2 refs., 4 figs., 2 tabs.

  17. Formation and reduction of carcinogenic furan in various model systems containing food additives.

    Science.gov (United States)

    Kim, Jin-Sil; Her, Jae-Young; Lee, Kwang-Geun

    2015-12-15

    The aim of this study was to analyse and reduce furan in various model systems. Furan model systems consisting of monosaccharides (0.5M glucose and ribose), amino acids (0.5M alanine and serine) and/or 1.0M ascorbic acid were heated at 121°C for 25 min. The effects of food additives (each 0.1M) such as metal ions (iron sulphate, magnesium sulphate, zinc sulphate and calcium sulphate), antioxidants (BHT and BHA), and sodium sulphite on the formation of furan were measured. The level of furan formed in the model systems was 6.8-527.3 ng/ml. The level of furan in the model systems of glucose/serine and glucose/alanine increased 7-674% when food additives were added. In contrast, the level of furan decreased by 18-51% in the Maillard reaction model systems that included ribose and alanine/serine with food additives except zinc sulphate. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Glycine facilitates gamma-glutamylcysteinylethyl ester-mediated increase in liver glutathione level.

    Science.gov (United States)

    Nishida, K; Ohta, Y; Ishiguro, I

    1997-08-27

    gamma-Glutamylcysteinylethyl ester (gamma-GCE) increases reduced glutathione (GSH) levels in GSH-depleted rat hepatocytes. Because glycine, a constituent of GSH, exists at 0.3 to 0.4 mM in rat plasma, we examined the influence of glycine added to the medium on the action of gamma-GCE to increase GSH levels in the rat hepatocytes. Glycine (0.2-0.8 mM) dose-dependently enhanced gamma-GCE-mediated increase in intracellular GSH levels with an increase in intracellular gamma-GCE levels. These results indicate that exogenous glycine facilitates gamma-GCE-mediated increase in intracellular GSH levels in rat hepatocytes possibly by enhancing the uptake of gamma-GCE into the cells.

  19. EPR structure of the gamma irradiated alanine spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Cabral P, A; Jimenez D, H; Urena N, F; Galindo, S; Bosch, P

    1992-03-15

    In this study is shown that the broadened five-line EPR pattern of the gamma irradiated alanine possibly decomposes into a more complex pattern when the recorded spectrum is subject to an operation of deconvolution. The EPR powder spectra of gamma irradiated DL- and L-alanine with and without binders are analysed. In all recorded spectra, each observed line is resolved into an asymmetrical triplet when a Gaussian distribution of 8.2 gauss width is removed, by deconvolution, from the observed spectrum. On the other hand, from a simple fitting analysis carried out on the original data, one encounters that some calculated relations between characteristic parameters, such as intensity ratios, deviate consistently from assumed height ratios. Both, from deconvolution and fitting results, a different structure is suggested for the observed broadened five-line EPR pattern of {gamma}-irradiated powder DL- and L-alanine. (Author)

  20. EPR structure of the gamma irradiated alanine spectrum

    International Nuclear Information System (INIS)

    Cabral P, A.; Jimenez D, H.; Urena N, F.; Galindo, S.; Bosch, P.

    1992-03-01

    In this study is shown that the broadened five-line EPR pattern of the gamma irradiated alanine possibly decomposes into a more complex pattern when the recorded spectrum is subject to an operation of deconvolution. The EPR powder spectra of gamma irradiated DL- and L-alanine with and without binders are analysed. In all recorded spectra, each observed line is resolved into an asymmetrical triplet when a Gaussian distribution of 8.2 gauss width is removed, by deconvolution, from the observed spectrum. On the other hand, from a simple fitting analysis carried out on the original data, one encounters that some calculated relations between characteristic parameters, such as intensity ratios, deviate consistently from assumed height ratios. Both, from deconvolution and fitting results, a different structure is suggested for the observed broadened five-line EPR pattern of γ-irradiated powder DL- and L-alanine. (Author)

  1. The unresolved puzzle why alanine extensions cause disease.

    Science.gov (United States)

    Winter, Reno; Liebold, Jens; Schwarz, Elisabeth

    2013-08-01

    The prospective increase in life expectancy will be accompanied by a rise in the number of elderly people who suffer from ill health caused by old age. Many diseases caused by aging are protein misfolding diseases. The molecular mechanisms underlying these disorders receive constant scientific interest. In addition to old age, mutations also cause congenital protein misfolding disorders. Chorea Huntington, one of the most well-known examples, is caused by triplet extensions that can lead to more than 100 glutamines in the N-terminal region of huntingtin, accompanied by huntingtin aggregation. So far, nine disease-associated triplet extensions have also been described for alanine codons. The extensions lead primarily to skeletal malformations. Eight of these proteins represent transcription factors, while the nuclear poly-adenylate binding protein 1, PABPN1, is an RNA binding protein. Additional alanines in PABPN1 lead to the disease oculopharyngeal muscular dystrophy (OPMD). The alanine extension affects the N-terminal domain of the protein, which has been shown to lack tertiary contacts. Biochemical analyses of the N-terminal domain revealed an alanine-dependent fibril formation. However, fibril formation of full-length protein did not recapitulate the findings of the N-terminal domain. Fibril formation of intact PABPN1 was independent of the alanine segment, and the fibrils displayed biochemical properties that were completely different from those of the N-terminal domain. Although intranuclear inclusions have been shown to represent the histochemical hallmark of OPMD, their role in pathogenesis is currently unclear. Several cell culture and animal models have been generated to study the molecular processes involved in OPMD. These studies revealed a number of promising future therapeutic strategies that could one day improve the quality of life for the patients.

  2. Brain alanine formation as an ammonia-scavenging pathway during hyperammonemia

    DEFF Research Database (Denmark)

    Dadsetan, Sherry; Kukolj, Eva; Bak, Lasse Kristoffer

    2013-01-01

    (MSO) enhances incorporation of (15)NH4(+) in alanine during acute hyperammonemia. We observed a fourfold increased amount of (15)NH4 incorporation in brain alanine in rats treated with MSO. Furthermore, co-cultures of neurons and astrocytes exposed to (15)NH4Cl in the absence or presence of MSO...... demonstrated a dose-dependent incorporation of (15)NH4 into alanine together with increased (15)N incorporation in glutamate. These findings provide evidence that ammonia is detoxified by the concerted action of GDH and ALAT both in vivo and in vitro, a mechanism that is accelerated in the presence of MSO...

  3. Isotope effect of optical activity measurements on L-α-alanine

    International Nuclear Information System (INIS)

    Darge, W.; Laczko, I.; Thiemann, W.

    1976-01-01

    If an optically active organic substance is labelled in the chirality center with another isotopic species (such as 15 N for 14 N) a pronounced variation of rotatory power is predicted. It was tried to varify this idea experimentally on L-α-alanine and found an isotope effect in ORD (optical rotatory dispersion). The magnitude of the rotation is mainly dependent on the pH of the solvent. The ratio of the optical activity alanine- 14 N/alanine- 15 N is about 1.02. It can be seen that the ratios of the molecular rotations are consistently lower than the corresponding ratios of the specific rotations. This is of course due to the fact that the molecular mass 15 M is larger than 14 M. This means tthat the mass difference is already taken into account so that the ratio of the molecular rotations could be defined as the ''net'' isotope effect in the ORDs of 15 N-substitued alanine. From the fact the ORD is different for the isotope-substitued alanine, one can reasonably assume that the absorption coefficient is also different. This leads to speculations about certain problems in the chemical evolution of the biosphere, such as the origin of optical activity. (T.G.)

  4. Structure and Intramolecular Proton Transfer of Alanine Radical Cations

    International Nuclear Information System (INIS)

    Lee, Gab Yong

    2012-01-01

    The structures of the four lowest alanine conformers, along with their radical cations and the effect of ionization on the intramolecular proton transfer process, are studied using the density functional theory and MP2 method. The energy order of the radical cations of alanine differs from that of the corresponding neutral conformers due to changes in the basicity of the NH 2 group upon ionization. Ionization favors the intramolecular proton transfer process, leading to a proton-transferred radical-cation structure, [NH 3 + -CHCH 3 -COO·], which contrasts with the fact that a proton-transferred zwitterionic conformer is not stable for a neutral alanine in the gas phase. The energy barrier during the proton transfer process is calculated to be about 6 kcal/mol

  5. Mosaic serine proteases in the mammalian central nervous system.

    Science.gov (United States)

    Mitsui, Shinichi; Watanabe, Yoshihisa; Yamaguchi, Tatsuyuki; Yamaguchi, Nozomi

    2008-01-01

    We review the structure and function of three kinds of mosaic serine proteases expressed in the mammalian central nervous system (CNS). Mosaic serine proteases have several domains in the proenzyme fragment, which modulate proteolytic function, and a protease domain at the C-terminus. Spinesin/TMPRSS5 is a transmembrane serine protease whose presynaptic distribution on motor neurons in the spinal cord suggests that it is significant for neuronal plasticity. Cell type-specific alternative splicing gives this protease diverse functions by modulating its intracellular localization. Motopsin/PRSS12 is a mosaic protease, and loss of its function causes mental retardation. Recent reports indicate the significance of this protease for cognitive function. We mention the fibrinolytic protease, tissue plasminogen activator (tPA), which has physiological and pathological functions in the CNS.

  6. Development of portable ESR spectrometer as a reader for alanine dosimeters

    International Nuclear Information System (INIS)

    Kojima, T.; Haruyama, Y.; Tachibana, H.; Tanaka, R.; Okamoto, J.

    1993-01-01

    A prototype portable electron spin resonance (ESR) spectrometer was designed and tested, and its feasibility as a reader of alanine dosimeters was studied from the two standpoints of reproducibility of readings and sensitivity sufficient for dosimetry in the absorbed dose range 1-100 kGy. It has two main components: a permanent magnet and resonator; and a unit box with a microwave and auto-frequency control (AFC) circuit, a sweep controller of magnetic field, display, etc. In the present preliminary study, reproducibility values are measured with the same ESR parameters and alanine-polystyrene (alanine-PS) dosimeter at a dose of 1 kGy: repeatedly measuring without removing dosimeter from the cavity; individual measurement with removing and inserting again into the cavity with readjustment of ESR parameters. Alanine/ESR dosimetry using this spectrometer has a measurable dose range from 1 to 100 kGy with relatively high precision within ± 3% (1σ) as a preliminary result. The portable ESR spectrometer may also be modified as an automatic, more precise, dedicated alanine dosimeter reader. (author)

  7. Impaired absorption of marked oligopeptide Glycine-I Tyrosine-Glycine after successful autologous-allotopic ileal mucosa transplantation in beagles.

    Science.gov (United States)

    Beiler, H A; Steinorth, J; Witt, A; Mier, W; Mohammed, A; Waag, K L; Zachariou, Z

    2004-10-01

    After establishing a method for ileal mucosa transplantation in an animal model, the authors investigated the absorptive capacity for oligopeptides of the transplanted mucosa. In 14 beagle dogs the authors transplanted ileal mucosa in a vascularized demucosed segment of the transverse colon. The colonic wall-ileal mucosa complex then was integrated in the ileal continuity. Six animals were lost owing to operative complications. Absorptive capacity for oligopeptides was measured in the remaining 8 animals with the iodine 131 (131I)-marked tripeptide glycine-tyrosine-glycine before and 4 weeks after transplantation. The results were compared and analyzed with the Student's t test for matched pairs. Blood concentrations of the marked tripeptide with P value less than .05 were considered as a significant reduction in the absorptive capacity of the transplanted ileal mucosa. After fixation with glutaraldehyd graft, uptake of the colonic wall-ileal mucosa complex was evaluated histologically in 8 animals. In all 8 animals, a 100% graft uptake was verified in all sections. Fifteen minutes after application of 15 MBc Glycine-131I-Tyrosine-Glycine there was no significant difference in the absorption between normal and transplanted ileal mucosa. After 30 minutes, the absorption of the transplanted ileal mucosa showed a tendency (P < .1) for an impaired uptake of the marked tripeptide. However, 60 minutes after application the difference in the absorptive capacity of the transplanted ileal mucosa was significant (P < .05). Autologous allotopic ileal mucosa transplantation is feasible; however, an impaired absorption of oligopeptides of the transplanted mucosa 4 weeks after transplantation could be observed.

  8. d-Alanine metabolism is essential for growth and biofilm formation of Streptococcus mutans.

    Science.gov (United States)

    Qiu, W; Zheng, X; Wei, Y; Zhou, X; Zhang, K; Wang, S; Cheng, L; Li, Y; Ren, B; Xu, X; Li, Y; Li, M

    2016-10-01

    Part of the d-alanine (d-Ala) metabolic pathway in bacteria involves the conversion of l-alanine to d-Ala by alanine racemase and the formation of d-alanyl-d-alanine by d-alanine-d-alanine ligase, the product of which is involved in cell wall peptidoglycan synthesis. At present, drugs that target the metabolic pathway of d-Ala are already in clinical use - e.g. d-cycloserine (DCS) is used as an antibiotic against Mycobacterium tuberculosis. Streptococcus mutans is the main cariogenic bacterium in the oral cavity. Its d-Ala metabolism-associated enzymes alanine racemase and d-alanine-d-alanine ligase are encoded by the genes smu.1834 and smu.599, respectively, which may be potential targets for inhibitors. In this study, the addition of DCS blocked the d-Ala metabolic pathway in S. mutans, leading to bacterial cell wall defects, significant inhibition of bacterial growth and biofilm formation, and reductions in extracellular polysaccharide production and bacterial adhesion. However, the exogenous addition of d-Ala could reverse the inhibitory effect of DCS. Through the means of drug regulation, our study demonstrated, for the first time, the importance of d-Ala metabolism in the survival and biofilm formation of S. mutans. If the growth of S. mutans can be specifically inhibited by designing drugs that target d-Ala metabolism, then this may serve as a potential new treatment for dental caries. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Identification and characterization of fusolisin, the Fusobacterium nucleatum autotransporter serine protease.

    Directory of Open Access Journals (Sweden)

    Lior Doron

    Full Text Available Fusobacterium nucleatum is an oral anaerobe associated with periodontal disease, adverse pregnancy outcomes and colorectal carcinoma. A serine endopeptidase of 61-65 kDa capable of damaging host tissue and of inactivating immune effectors was detected previously in F. nucleatum. Here we describe the identification of this serine protease, named fusolisin, in three oral F. nucleatum sub-species. Gel zymogram revealed fusobacterial proteolytic activity with molecular masses ranging from 55-101 kDa. All of the detected proteases were inhibited by the serine protease inhibitor PMSF. analysis revealed that all of the detected proteases are encoded by genes encoding an open reading frame (ORF with a calculated mass of approximately 115 kDa. Bioinformatics analysis of the identified ORFs demonstrated that they consist of three domains characteristic of autotransporters of the type Va secretion system. Our results suggest that the F. nucleatum fusolisins are derived from a precursor of approximately 115 kDa. After crossing the cytoplasmic membrane and cleavage of the leader sequence, the C-terminal autotransporter domain of the remaining 96-113 kDa protein is embedded in the outer membrane and delivers the N-terminal S8 serine protease passenger domain to the outer cell surface. In most strains the N-terminal catalytic 55-65 kDa domain self cleaves and liberates itself from the autotransporter domain after its transfer across the outer cell membrane. In F. nucleatum ATCC 25586 this autocatalytic activity is less efficient resulting in a full length membrane-anchored serine protease. The mature serine protease was found to cleave after Thr, Gly, Ala and Leu residues at the P1 position. Growth of F. nucleatum in complex medium was inhibited when serine protease inhibitors were used. Additional experiments are needed to determine whether fusolisin might be used as a target for controlling fusobacterial infections.

  10. Synthesis of silver nanoparticles using DL-alanine for ESR dosimetry applications

    International Nuclear Information System (INIS)

    Guidelli, Eder José; Ramos, Ana Paula; Zaniquelli, Maria Elisabete D.; Nicolucci, Patricia; Baffa, Oswaldo

    2012-01-01

    The potential use of alanine for the production of nanoparticles is presented here for the first time. Silver nanoparticles were synthesized using a simple green method, namely the thermal treatment of silver nitrate aqueous solutions with DL-alanine. The latter compound was employed both as a reducing and a capping agent. Particles with average size equal to 7.5 nm, face-centered cubic crystalline structure, narrow size distribution, and spherical shape were obtained. Interaction between the silver ions present on the surface of the nanoparticles and the amine group of the DL-alanine molecule seems to be responsible for reduction of the silver ions and for the stability of the colloid. The bio-hybrid nano-composite was used as an ESR dosimeter. The amount of silver nanoparticles in the nanocomposite was not sufficient to cause considerable loss of tissue equivalency. Moreover, the samples containing nanoparticles presented increased sensitivity and reduced energetic dependence as compared with pure DL-alanine, contributing to the construction of small-sized dosimeters. - Highlights: ► The synthesis is environmentally benign, easy to perform, and of low-cost. ► DL-Alanine was employed both as reducing and capping agent. ► Mean size of 7.5 nm, narrow size distribution, and spherical shape of particles. ► Increased sensitivity and reduced energetic dependence compared with pure alanine. ► The nanocomposite has potential application for ESR dosimetry.

  11. Prolonged continuous intravenous infusion of the dipeptide L-alanine- L-glutamine significantly increases plasma glutamine and alanine without elevating brain glutamate in patients with severe traumatic brain injury.

    Science.gov (United States)

    Nägeli, Mirjam; Fasshauer, Mario; Sommerfeld, Jutta; Fendel, Angela; Brandi, Giovanna; Stover, John F

    2014-07-02

    Low plasma glutamine levels are associated with worse clinical outcome. Intravenous glutamine infusion dose- dependently increases plasma glutamine levels, thereby correcting hypoglutaminemia. Glutamine may be transformed to glutamate which might limit its application at a higher dose in patients with severe traumatic brain injury (TBI). To date, the optimal glutamine dose required to normalize plasma glutamine levels without increasing plasma and cerebral glutamate has not yet been defined. Changes in plasma and cerebral glutamine, alanine, and glutamate as well as indirect signs of metabolic impairment reflected by increased intracranial pressure (ICP), lactate, lactate-to-pyruvate ratio, electroencephalogram (EEG) activity were determined before, during, and after continuous intravenous infusion of 0.75 g L-alanine-L-glutamine which was given either for 24 hours (group 1, n = 6) or 5 days (group 2, n = 6) in addition to regular enteral nutrition. Lab values including nitrogen balance, urea and ammonia were determined daily. Continuous L-alanine-L-glutamine infusion significantly increased plasma and cerebral glutamine as well as alanine levels, being mostly sustained during the 5 day infusion phase (plasma glutamine: from 295 ± 62 to 500 ± 145 μmol/ l; brain glutamine: from 183 ± 188 to 549 ± 120 μmol/ l; plasma alanine: from 327 ± 91 to 622 ± 182 μmol/ l; brain alanine: from 48 ± 55 to 89 ± 129 μmol/ l; p alanine-L-glutamine infusion (0.75 g/ kg/ d up to 5 days) increased plasma and brain glutamine and alanine levels. This was not associated with elevated glutamate or signs of potential glutamate-mediated cerebral injury. The increased nitrogen load should be considered in patients with renal and hepatic dysfunction. Clinicaltrials.gov NCT02130674. Registered 5 April 2014.

  12. Changes in alanine turnover rate due to nutritional and genetic obesity in the rat.

    Science.gov (United States)

    Yebras, M; Salvadó, J; Arola, L; Remesar, X; Segués, T

    1994-08-01

    The changes in alanine turnover were determined in Zucker rats, which were either genetically obese (fa/fa) or rendered obese by dietary treatment (cafeteria fed). The whole body rate of alanine turnover was higher in genetically obese rats than in rats in which obesity was induced by diet (cafeteria). This is possibly due to variations in the rate of the amino acid incorporation into proteins, since the rate of whole body alanine degradation is the same for both groups. Thus, the different pattern followed by alanine turnover rate in these types of obese animals reflects the differences in the nitrogen economy of these animals, pointing to a higher alanine utilization in the genetically obese animals and a conservative management of alanine in the cafeteria-fed animals.

  13. Ketamine Metabolites Enantioselectively Decrease Intracellular D-Serine Concentrations in PC-12 Cells.

    Directory of Open Access Journals (Sweden)

    Nagendra S Singh

    Full Text Available D-Serine is an endogenous NMDA receptor co-agonist that activates synaptic NMDA receptors modulating neuronal networks in the cerebral cortex and plays a key role in long-term potentiation of synaptic transmission. D-serine is associated with NMDA receptor neurotoxicity and neurodegeneration and elevated D-serine concentrations have been associated with Alzheimer's and Parkinsons' diseases and amyotrophic lateral sclerosis. Previous studies have demonstrated that the ketamine metabolites (rac-dehydronorketamine and (2S,6S-hydroxynorketamine decrease intracellular D-serine concentrations in a concentration dependent manner in PC-12 cells. In the current study, PC-12 cells were incubated with a series of ketamine metabolites and the IC50 values associated with attenuated intracellular D-serine concentrations were determined. The results demonstrate that structural and stereochemical features of the studied compounds contribute to the magnitude of the inhibitory effect with (2S,6S-hydroxynorketamine and (2R,6R-hydroxynorketamine displaying the most potent inhibition with IC50 values of 0.18 ± 0.04 nM and 0.68 ± 0.09 nM. The data was utilized to construct a preliminary 3D-QSAR/pharmacophore model for use in the design of new and more efficient modulators of D-serine.

  14. Synthesis and Characterization of Novel Acyl-Glycine Inhibitors of GlyT2.

    Science.gov (United States)

    Mostyn, Shannon N; Carland, Jane E; Shimmon, Susan; Ryan, Renae M; Rawling, Tristan; Vandenberg, Robert J

    2017-09-20

    It has been demonstrated previously that the endogenous compound N-arachidonyl-glycine inhibits the glycine transporter GlyT2, stimulates glycinergic neurotransmission, and provides analgesia in animal models of neuropathic and inflammatory pain. However, it is a relatively weak inhibitor with an IC 50 of 9 μM and is subject to oxidation via cyclooxygenase, limiting its therapeutic value. In this paper we describe the synthesis and testing of a novel series of monounsaturated C18 and C16 acyl-glycine molecules as inhibitors of the glycine transporter GlyT2. We demonstrate that they are up to 28 fold more potent that N-arachidonyl-glycine with no activity at the closely related GlyT1 transporter at concentrations up to 30 μM. This novel class of compounds show considerable promise as a first generation of GlyT2 transport inhibitors.

  15. EPR dosimetry of radiotherapy photon beams in inhomogeneous media using alanine films

    Energy Technology Data Exchange (ETDEWEB)

    Oesteraas, Bjoern Helge [Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway); Hole, Eli Olaug [Department of Physics, University of Oslo, PO Box 1048 Blindern, N-0316 Oslo (Norway); Olsen, Dag Rune [Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway); Malinen, Eirik [Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway)

    2006-12-21

    In the current work, EPR (electron paramagnetic resonance) dosimetry using alanine films (134 {mu}m thick) was utilized for dose measurements in inhomogeneous phantoms irradiated with radiotherapy photon beams. The main phantom material was PMMA, while either Styrofoam or aluminium was introduced as an inhomogeneity. The phantoms were irradiated to a maximum dose of about 30 Gy with 6 or 15 MV photons. The performance of the alanine film dosimeters was investigated and compared to results from ion chamber dosimetry, Monte Carlo simulations and radiotherapy treatment planning calculations. It was found that the alanine film dosimeters had a linear dose response above approximately 5 Gy, while a background signal obscured the response at lower dose levels. For doses between 5 and 60 Gy, the standard deviation of single alanine film dose estimates was about 2%. The alanine film dose estimates yielded results comparable to those from the Monte Carlo simulations and the ion chamber measurements, with absolute differences between estimates in the order of 1-15%. The treatment planning calculations exhibited limited applicability. The current work shows that alanine film dosimetry is a method suitable for estimating radiotherapeutical doses and for dose measurements in inhomogeneous media.

  16. EPR dosimetry of radiotherapy photon beams in inhomogeneous media using alanine films

    International Nuclear Information System (INIS)

    Oesteraas, Bjoern Helge; Hole, Eli Olaug; Olsen, Dag Rune; Malinen, Eirik

    2006-01-01

    In the current work, EPR (electron paramagnetic resonance) dosimetry using alanine films (134 μm thick) was utilized for dose measurements in inhomogeneous phantoms irradiated with radiotherapy photon beams. The main phantom material was PMMA, while either Styrofoam or aluminium was introduced as an inhomogeneity. The phantoms were irradiated to a maximum dose of about 30 Gy with 6 or 15 MV photons. The performance of the alanine film dosimeters was investigated and compared to results from ion chamber dosimetry, Monte Carlo simulations and radiotherapy treatment planning calculations. It was found that the alanine film dosimeters had a linear dose response above approximately 5 Gy, while a background signal obscured the response at lower dose levels. For doses between 5 and 60 Gy, the standard deviation of single alanine film dose estimates was about 2%. The alanine film dose estimates yielded results comparable to those from the Monte Carlo simulations and the ion chamber measurements, with absolute differences between estimates in the order of 1-15%. The treatment planning calculations exhibited limited applicability. The current work shows that alanine film dosimetry is a method suitable for estimating radiotherapeutical doses and for dose measurements in inhomogeneous media

  17. Structural features and kinetic characterization of alanine racemase from Bacillus pseudofirmus OF4.

    Science.gov (United States)

    Dong, Hui; Hu, Tingting; He, Guangzheng; Lu, Deren; Qi, Jianxun; Dou, Yanshu; Long, Wei; He, Xin; Ju, Jiansong; Su, Dan

    2018-02-26

    Alanine racemase (Alr) is a pyridoxal-5'-phosphate-dependent (PLP) enzyme that catalyzes a reversible racemization between the enantiomers of alanine. d-Alanine is an indispensable constituent in the biosynthesis of bacterial cell-wall peptidoglycan, and its inhibition is lethal to prokaryotes, which makes it an attractive target for designing antibacterial drugs. In this study, the molecular structure of alanine racemase from Bacillus pseudofirmus OF4 (DadX OF4 ) was determined by X-ray crystallography to a resolution of 1.8 Å. The comparison of DadX OF4 with alanine racemases from other bacteria demonstrated a conserved overall fold. Enzyme kinetics analysis showed that the conserved residues at the substrate entryway and the salt bridge at the dimer interface are critical for enzyme activity. These structural and biochemical findings provide a template for future structure-based drug-development efforts targeting alanine racemases. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Alanine Radiation Detectors in Therapeutic Carbon Ion Beams

    DEFF Research Database (Denmark)

    Herrmann, Rochus; Jäkel, Oliver; Palmans, Hugo

    of the depth dose curves. Solid state detectors, such as diamond detectors, radiochromic films, TLDs and the amino acid alanine are used due to there good spatial resolution. If used in particle beams their response often exhibits a dependence on particle energy and type, so the acquired signal is not always...... proportional to absorbed dose. A model by Hansen and Olsen, based on the Track Structure Theory is available, which can predict the relative efficiency of some detectors, when the particle spectrum is known. For alanine detectors the model was successfully validated by Hansen and Olsen for several ion species...... at energies below 20 MeV/u. We implemented this model in the Monte Carlo code FLUKA. At the GSI heavy ion facility in Darmstadt, Germany, alanine has been irradiated with carbon ions at energies between 88 an 400 MeV/u, which is the energy range used for therapy. The irradiation and the detector response have...

  19. Engineering of High Yield Production of L-serine in Escherichia coli

    DEFF Research Database (Denmark)

    Mundhada, Hemanshu; Schneider, Konstantin; Christensen, Hanne Bjerre

    2016-01-01

    by deletion of three L-serine deaminases sdaA, sdaB, and tdcG, as well as serine hydroxyl methyl transferase (SHMT) encoded by glyA. Upon overexpression of the serine production pathway, consisting of a feedback resistant version of serA along with serB and serC, this quadruple deletion strain showed a very...

  20. Green reduction of graphene oxide using alanine

    International Nuclear Information System (INIS)

    Wang, Jiabin; Salihi, Elif Caliskan; Šiller, Lidija

    2017-01-01

    There remains a real need for the easy, eco-friendly and scalable preparation method of graphene due to various potential applications. Chemical reduction is the most versatile method for the large scale production of graphene. Here we report the operating conditions for a one-step, economical and green synthesis method for the reduction of graphene oxide using a biomolecule (alanine). Graphene oxide was produced by the oxidation and exfoliation of natural graphite flake with strong oxidants using Hummers method (Hummers and Offeman, 1958), but the method was revised in our laboratory to set up a safe and environmentally friendly route. The reduction of graphene oxide was investigated using alanine at various operating conditions in order to set up optimum conditions (treatment time, temperature and concentration of the reagent). Samples have been characterized by using UV–Visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, Raman spectroscopy and X-ray diffraction analysis. - Highlights: • An environmentally friendly route was reported for the chemical reduction of graphene oxide (GO). • Alanine could reduce GO to rGO (reduced graphene oxide) without using any stabilizer or alcaline medium. • Characterization studies confirmed the successful deoxygenation of GO.

  1. Green reduction of graphene oxide using alanine

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jiabin [Newcastle University, School of Chemical Engineering and Advanced Materials, Newcastle upon Tyne NE1 7RU (United Kingdom); Salihi, Elif Caliskan, E-mail: caliskanelif@gmail.com [Newcastle University, School of Chemical Engineering and Advanced Materials, Newcastle upon Tyne NE1 7RU (United Kingdom); Marmara University, Faculty of Pharmacy, Department of Basic Pharmaceutical Sciences, 34668 Istanbul (Turkey); Šiller, Lidija [Newcastle University, School of Chemical Engineering and Advanced Materials, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2017-03-01

    There remains a real need for the easy, eco-friendly and scalable preparation method of graphene due to various potential applications. Chemical reduction is the most versatile method for the large scale production of graphene. Here we report the operating conditions for a one-step, economical and green synthesis method for the reduction of graphene oxide using a biomolecule (alanine). Graphene oxide was produced by the oxidation and exfoliation of natural graphite flake with strong oxidants using Hummers method (Hummers and Offeman, 1958), but the method was revised in our laboratory to set up a safe and environmentally friendly route. The reduction of graphene oxide was investigated using alanine at various operating conditions in order to set up optimum conditions (treatment time, temperature and concentration of the reagent). Samples have been characterized by using UV–Visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, Raman spectroscopy and X-ray diffraction analysis. - Highlights: • An environmentally friendly route was reported for the chemical reduction of graphene oxide (GO). • Alanine could reduce GO to rGO (reduced graphene oxide) without using any stabilizer or alcaline medium. • Characterization studies confirmed the successful deoxygenation of GO.

  2. Implementation of an alanine dosimetry service

    International Nuclear Information System (INIS)

    Gago Arias, A.; Nunez Pelaez, N.; Peteiro Vilaseco, E.; Gomez Rodriguez, F.; Gonzalez Castano, D. M.

    2011-01-01

    This work facing the implementation of an alanine dosimetry service, linked to the installation of Co 6 0 Radio physics Laboratory (LP) and Paramagnetic Resonance Service of the University of Santiago de Compostela (USC).

  3. Light intensity affects the uptake and metabolism of glycine by pakchoi (Brassica chinensis L.)

    Science.gov (United States)

    Ma, Qingxu; Cao, Xiaochuang; Wu, Lianghuan; Mi, Wenhai; Feng, Ying

    2016-02-01

    The uptake of glycine by pakchoi (Brassica chinensis L.), when supplied as single N-source or in a mixture of glycine and inorganic N, was studied at different light intensities under sterile conditions. At the optimal intensity (414 μmol m-2 s-1) for plant growth, glycine, nitrate, and ammonium contributed 29.4%, 39.5%, and 31.1% shoot N, respectively, and light intensity altered the preferential absorption of N sources. The lower 15N-nitrate in root but higher in shoot and the higher 15N-glycine in root but lower in shoot suggested that most 15N-nitrate uptake by root transported to shoot rapidly, with the shoot being important for nitrate assimilation, and the N contribution of glycine was limited by post-uptake metabolism. The amount of glycine that was taken up by the plant was likely limited by root uptake at low light intensities and by the metabolism of ammonium produced by glycine at high light intensities. These results indicate that pakchoi has the ability to uptake a large quantity of glycine, but that uptake is strongly regulated by light intensity, with metabolism in the root inhibiting its N contribution.

  4. A kinetic model for the glucose/glycine Maillard reaction pathways

    NARCIS (Netherlands)

    Martins, S.I.F.S.; Boekel, van M.A.J.S.

    2005-01-01

    A comprehensive kinetic model for the glucose/glycine Maillard reaction is proposed based on an approach called multiresponse kinetic modelling. Special attention was paid to reactants, intermediates and end products: -fructose, N-(1-deoxy--fructos-1-yl)-glycine (DFG), 1-deoxy-2,3-hexodiulose and

  5. Rapid Methods to Distinguish Heterodera schachtii from Heterodera glycines Using PCR Technique

    Directory of Open Access Journals (Sweden)

    Hyoung Rai Ko

    2017-09-01

    Full Text Available The purpose of this study was to develop rapid methods for distinguishing between Heterodera schachtii and H. glycines detected from chinese cabbage fields of highland in Gangwon, Korea. To do this, we performed PCR-RFLP and PCR with the primers set developed in this study for GC147, GC408 and PM001 population, H. schachtii, and YS224, DA142 and BC115 population, H. glycines. Eight restriction enzymes generated RFLP profiles of mtDNA COI region for populations of H. schachtii and H. glycines, repectively. As a result, treatment of two restriction enzymes, RsaI and HinfI, were allowed to distinguish H. schachtii from H. glycines based on the differences of DNA band patterns. The primer set, #JBS1, #JBG1 and #JB3R, amplified specific fragments with 277 and 339 bp of H. schachtii, 339 bp of H. glycines, respectively, while it did not amplify fragments from three root-knot nematodes and two root-lesion nematodes. Thus, the primer set developed in this study could be a good method, which is used to distinguish between H. schachtii and H. glycines.

  6. A DFT study of adsorption of glycine onto the surface of BC_2N nanotube

    International Nuclear Information System (INIS)

    Soltani, Alireza; Azmoodeh, Zivar; Javan, Masoud Bezi; Lemeski, E. Tazikeh; Karami, Leila

    2016-01-01

    Highlights: • Glycine adsorption over the pristine BC_2N nanotubes is investigated by DFT calculations. • Adsorption of glycine in its zwitterionic form is stronger in comparison with the radical form. • Adsorption of glycine from its amine head on adsorbent leads to a significant decrease in the electronic properties. - Abstract: A theoretical study of structure and the energy interaction of amino acid glycine (NH_2CH_2COOH) with BC_2N nanotube is crucial for apperception behavior occurring at the nanobiointerface. Herein, we studied the adsorption of glycine in their radical and zwitterionic forms upon the surface of BC_2N nanotube using M06 functional and 6-311G** standard basis set. We also considered the different orientations of the glycine amino acid on the surface of adsorbent. Further, we found out that the stability of glycine from its carbonyl group is higher than hydroxyl and amine groups. Our results also indicated that the electronic structure of BC_2N nanotube on the adsorption of glycine from its amine group is more altered than the other groups. Our study exhibits that opto-electronic property of adsorbent is changed after the glycine adsorption.

  7. Evidence for brain glucose dysregulation in Alzheimer's disease.

    Science.gov (United States)

    An, Yang; Varma, Vijay R; Varma, Sudhir; Casanova, Ramon; Dammer, Eric; Pletnikova, Olga; Chia, Chee W; Egan, Josephine M; Ferrucci, Luigi; Troncoso, Juan; Levey, Allan I; Lah, James; Seyfried, Nicholas T; Legido-Quigley, Cristina; O'Brien, Richard; Thambisetty, Madhav

    2018-03-01

    It is unclear whether abnormalities in brain glucose homeostasis are associated with Alzheimer's disease (AD) pathogenesis. Within the autopsy cohort of the Baltimore Longitudinal Study of Aging, we measured brain glucose concentration and assessed the ratios of the glycolytic amino acids, serine, glycine, and alanine to glucose. We also quantified protein levels of the neuronal (GLUT3) and astrocytic (GLUT1) glucose transporters. Finally, we assessed the relationships between plasma glucose measured before death and brain tissue glucose. Higher brain tissue glucose concentration, reduced glycolytic flux, and lower GLUT3 are related to severity of AD pathology and the expression of AD symptoms. Longitudinal increases in fasting plasma glucose levels are associated with higher brain tissue glucose concentrations. Impaired glucose metabolism due to reduced glycolytic flux may be intrinsic to AD pathogenesis. Abnormalities in brain glucose homeostasis may begin several years before the onset of clinical symptoms. Copyright © 2017 the Alzheimer's Association. All rights reserved.

  8. The effects of lead on the gaseous exchange and photosynthetic carbon metabolism of pea seedlings

    Directory of Open Access Journals (Sweden)

    Jerzy W. Poskuta

    2014-01-01

    Full Text Available Roots of whole 3 week-old pea seedlings (Pisum sativum L. var. "Bordi" were immersed for 24 h in solutions of lead chloride at Pb copcentrations of 200, 400, 800,12000 mg dm3. Accumulation of lead in roots was independent of the Pb concentration, whereas the accumulation of Pb in shoots was an almost linear function of the concentration of this element in the root medium. This treatment caused Pb concentration-dependent inhibition of apparent photosynthesis (APS, photorespiration (PR, 14CO2 uptake, stomatal opening and transpiration of shoots and also germination of seeds. The most sensitive to Pb contamination was CO2 exchange, then transpiration and to a lesser degree germination of seeds. Lead caused a considerable alteration of photosynthetic and photorespiratory carbon metabolism, restricted the 14C-labeling of: phosphoglycerate, ribose+ribulose, sucrose, glycolate and glycine+serine. Under conditions of C02 uptake limited by lead, an enhancement of the 14C-labeling of malate+citrate, alanine and glucose was observed.

  9. Nutritional optimization for anaerobic growth of Bacillus steaothermophilus LLD-16

    Directory of Open Access Journals (Sweden)

    Muhammad Javed

    2016-04-01

    Full Text Available In this study, a range of nutritional supplements including twenty amino acids, major vitamins and four nucleic acid bases were exploited as added-value supplements for the growth of a lactate-minus (ldh mutant Bacillus stearothermophilus LLD-16 under anaerobic environment. The chemostat studies revealed that five amino acids that includes aspartate, glutamate, isoleucine, methionine, and serine were essential for persuaded growth of B. stearothermophilus LLD-16. The anaerobic batch studies showed that a number of nutritional supplements, such as, p-aminobenzoic acid (PABA, folic acid, pantothenic acid, adenine, glycine, leucine, tryptophan, proline, alanine and α-ketoglutarate, when added individually, improved the biomass levels. In contrast, the higher concentrations of cyanocobalamine or biotin, guanine, uracil and isoleucine were found inhibitory. Furthermore, the study explains why the highest biomass formation cannot necessarily be achieved on the richest mixture of amino acids, and the inadequacy of the biosynthetic machinery is very much dependent on the growth conditions of the microorganism.

  10. Interactions between insect pollinators and the ornamental tree, Tecoma stans (L.

    Directory of Open Access Journals (Sweden)

    K.H. Jonathan

    2009-02-01

    Full Text Available Tecoma stans (Bignoniaceae is a native of Central America but occurs throughout tropical latitudes due to cultivation as an ornamental; in India it is also normally cultivated as an ornamental tree. The plant has two anthesis schedules in a day - one during 0500-0800hrs and another during 1500-1700hrs. Different species of bees and wasps collect pollen and nectar from the flowers during daylight hours, while hawk moths collect nectar during the 0530-0700hrs and 1630-1830hrs periods. The flowers are an important source of pollen and/or nectar for these insects, and all facilitate pollination. The nectar contains three common sugars: hexoses, glucose and fructose, and it is also a source of three essential amino acids: lysine, histidine and threonine, and eight non-essential amino acids: glycine, serine, proline, arginine, glutamic acid, cystine, cysteine and alanine. With these floral rewards, T. stans sustains pollinator populations in areas where it is cultivated.

  11. Identification of amino acids in Securigera securidaca, a popular medicinal herb in Iranian folk medicine

    Directory of Open Access Journals (Sweden)

    S.E. Sadat-Ebrahimi

    2014-01-01

    Full Text Available Securigera securidaca (L. Degen & Dorfl grows in different parts of Iran. The seeds of the species are used in Iranian folk medicine as an anti-diabetic agent. Many studies have established hypoglycemic effects of amino acids and in the present investigation, amino acids of Securigera securidaca seeds have been evaluated. The ground seeds were extracted using petroleum ether, hot ethanol and ethanol 50%, respectively. ethanol 50% extract was chromatographed over cation exchanging resin and the resulting amino acid fraction was subjected to HPLC after OPA derivatization and the amino acids were identified by comparing to standards. The results evidenced the presence of 19 amino acids in the plant extract including alanine, arginine, asparagine, aspartic acid, citrulline, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, serine, threonine, tyrosine and valine. Considering the role of some amino acids in diabetes the above amino acids could be noted as hypoglycemic agents of the plant seeds but further studies are necessary.

  12. Studies on effective atomic numbers and electron densities in amino acids and sugars in the energy range 30-1333 keV

    International Nuclear Information System (INIS)

    Gowda, Shivalinge; Krishnaveni, S.; Gowda, Ramakrishna

    2005-01-01

    The effective atomic numbers and electron densities of the amino acids glycine, alanine, serine, valine, threonine, leucine, isoleucine, aspartic acid, lysine, glutamic acid, histidine, phenylalanine, arginine, tyrosine, tryptophane and the sugars arabinose, ribose, glucose, galactose, mannose, fructose, rhamnose, maltose, melibiose, melezitose and raffinose at the energies 30.8, 35.0, 81.0, 145, 276.4, 302.9, 356, 383.9, 661.6, 1173 and 1332.5 keV were calculated by using the measured total attenuation cross-sections. The interpolations of total attenuation cross-sections for photons of energy E in elements of atomic number Z was performed using the logarithmic regression analysis of the XCOM data in the photon energy region 30-1500 keV. The best-fit coefficients obtained by a piece wise interpolation method were used to find the effective atomic number and electron density of the compounds. These values are found to be in good agreement with the theoretical values calculated based on XCOM data

  13. Studies on effective atomic numbers and electron densities in amino acids and sugars in the energy range 30-1333 keV

    Energy Technology Data Exchange (ETDEWEB)

    Gowda, Shivalinge [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India); Krishnaveni, S. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India); Gowda, Ramakrishna [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India)]. E-mail: ramakrishnagowda@yahoo.com

    2005-10-15

    The effective atomic numbers and electron densities of the amino acids glycine, alanine, serine, valine, threonine, leucine, isoleucine, aspartic acid, lysine, glutamic acid, histidine, phenylalanine, arginine, tyrosine, tryptophane and the sugars arabinose, ribose, glucose, galactose, mannose, fructose, rhamnose, maltose, melibiose, melezitose and raffinose at the energies 30.8, 35.0, 81.0, 145, 276.4, 302.9, 356, 383.9, 661.6, 1173 and 1332.5 keV were calculated by using the measured total attenuation cross-sections. The interpolations of total attenuation cross-sections for photons of energy E in elements of atomic number Z was performed using the logarithmic regression analysis of the XCOM data in the photon energy region 30-1500 keV. The best-fit coefficients obtained by a piece wise interpolation method were used to find the effective atomic number and electron density of the compounds. These values are found to be in good agreement with the theoretical values calculated based on XCOM data.

  14. Alanine-EPR as a transfer standard dosimetry system for low energy X radiation

    International Nuclear Information System (INIS)

    Khoury, H.J.; Silva, E.J. da; Mehta, K.; Barros, V.S. de; Asfora, V.K.; Guzzo, P.L.; Parker, A.G.

    2015-01-01

    The purpose of this paper is to evaluate the use of alanine-EPR as a transfer standard dosimetry system for low energy X radiation, such as that in RS-2400, which operates in the range from 25 to 150 kV and 2 to 45 mA. Two types of alanine dosimeters were investigated. One is a commercial alanine pellets from Aérial-Centre de Ressources Technologiques, France and one was prepared in our laboratory (LMRI-DEN/UFPE). The EPR spectra of the irradiated dosimeters were recorded in the Nuclear Energy Department of UFPE, using a Bruker EMX10 EPR spectrometer operating in the X-band. The alanine-EPR dosimetry system was calibrated in the range of 20–220 Gy in this X-ray field, against an ionization chamber calibrated at the relevant X-ray energy with traceability to PTB. The results showed that both alanine dosimeters presented a linear dose response the same sensitivity, when the EPR signal was normalized to alanine mass. The total uncertainty in the measured dose was estimated to be about 3%. The results indicate that it is possible to use the alanine-EPR dosimetry system for validation of a low-energy X ray irradiator, such as RS-2400.

  15. Effect of beta-alanine, with and without sodium bicarbonate, on 2000-m rowing performance.

    Science.gov (United States)

    Hobson, Ruth M; Harris, Roger C; Martin, Dan; Smith, Perry; Macklin, Ben; Gualano, Bruno; Sale, Craig

    2013-10-01

    To examine the effect of beta-alanine only and beta-alanine with sodium bicarbonate supplementation on 2,000-m rowing performance. Twenty well-trained rowers (age 23 ± 4 y; height 1.85 ± 0.08 m; body mass 82.5 ± 8.9 kg) were assigned to either a placebo or beta-alanine (6.4 g · d(-1) for 4 weeks) group. A 2,000-m rowing time trial (TT) was performed before supplementation (Baseline) and after 28 and 30 days of supplementation. The post supplementation trials involved supplementation with either maltodextrin or sodium bicarbonate in a double-blind, crossover design, creating four study conditions (placebo with maltodextrin; placebo with sodium bicarbonate; beta-alanine with maltodextrin; beta-alanine with sodium bicarbonate). Blood lactate, pH, bicarbonate, and base excess were measured pre-TT, immediately post-TT and at TT+5 min. Performance data were analyzed using magnitude based inferences. Beta-alanine supplementation was very likely to be beneficial to 2,000-m rowing performance (6.4 ± 8.1 s effect compared with placebo), with the effect of sodium bicarbonate having a likely benefit (3.2 ± 8.8 s). There was a small (1.1 ± 5.6 s) but possibly beneficial additional effect when combining chronic beta-alanine supplementation with acute sodium bicarbonate supplementation compared with chronic beta-alanine supplementation alone. Sodium bicarbonate ingestion led to increases in plasma pH, base excess, bicarbonate, and lactate concentrations. Both chronic beta-alanine and acute sodium bicarbonate supplementation alone had positive effects on 2,000-m rowing performance. The addition of acute sodium bicarbonate to chronic beta-alanine supplementation may further enhance rowing performance.

  16. Zwitterionization of glycine in water environment: Stabilization mechanism and NMR spectral signatures

    Science.gov (United States)

    Valverde, Danillo; da Costa Ludwig, Zélia Maria; da Costa, Célia Regina; Ludwig, Valdemir; Georg, Herbert C.

    2018-01-01

    At physiological conditions, myriads of biomolecules (e.g., amino acids, peptides, and proteins) exist predominantly in the zwitterionic structural form and their biological functions will result in these conditions. However these geometrical structures are inaccessible energetically in the gas phase, and at this point, stabilization of amino-acids in physiological conditions is still under debate. In this paper, the electronic properties of a glycine molecule in the liquid environment were studied by performing a relaxation of the glycine geometry in liquid water using the free energy gradient method combined with a sequential quantum mechanics/molecular mechanics approach. A series of Monte Carlo Metropolis simulations of the glycine molecule embedded in liquid water, followed by only a quantum mechanical calculation in each of them were carried out. Both the local and global liquid environments were emphasized to obtain nuclear magnetic resonance (NMR) parameters for the glycine molecule in liquid water. The results of the equilibrium structure in solution and the systematic study of the hydrogen bonds were used to discard the direct proton transfer from the carboxyl group to the ammonium group of the glycine molecule in water solution. The calculations of the Density Functional Theory (DFT) were performed to study the polarization of the solvent in the parameters of nuclear magnetic resonance of the glycine molecule in liquid water. DFT calculations predicted isotropic chemical changes on the H, C, N, and O atoms of glycine in liquid water solution which agree with the available experimental data.

  17. A critical role for glycine transporters in hyperexcitability disorders

    Directory of Open Access Journals (Sweden)

    Robert J Harvey

    2008-03-01

    Full Text Available Defects in mammalian glycinergic neurotransmission result in a complex motor disorder characterized by neonatal hypertonia and an exaggerated startle refl ex, known as hyperekplexia (OMIM 149400. This affects newborn children and is characterized by noise or touch-induced seizures that result in muscle stiffness and breath-holding episodes. Although rare, this disorder can have serious consequences, including brain damage and/or sudden infant death. The primary cause of hyperekplexia is missense and nonsense mutations in the glycine receptor (GlyR α1 subunit gene (GLRA1 on chromosome 5q33.1, although we have also discovered rare mutations in the genes encoding the GlyR β subunit (GLRB and the GlyR clustering proteins gephyrin (GPNH and collybistin (ARHGEF9. Recent studies of the Na+ /Cl--dependent glycine transporters GlyT1 and GlyT2 using mouse knockout models and human genetics have revealed that mutations in GlyT2 are a second major cause of hyperekplexia, while the phenotype of the GlyT1 knockout mouse resembles a devastating neurological disorder known as glycine encephalopathy (OMIM 605899. These findings highlight the importance of these transporters in regulating the levels of synaptic glycine.

  18. The effect of point mutations on structure and mechanical properties of collagen-like fibril: A molecular dynamics study

    Energy Technology Data Exchange (ETDEWEB)

    Marlowe, Ashley E.; Singh, Abhishek; Yingling, Yaroslava G., E-mail: yara_yingling@ncsu.edu

    2012-12-01

    Understanding sequence dependent mechanical and structural properties of collagen fibrils is important for the development of artificial biomaterials for medical and nanotechnological applications. Moreover, point mutations are behind many collagen associated diseases, including Osteogenesis Imperfecta (OI). We conducted a combination of classical and steered atomistic molecular dynamics simulations to examine the effect of point mutations on structure and mechanical properties of short collagen fibrils which include mutations of glycine to alanine, aspartic acid, cysteine, and serine or mutations of hydroxyproline to arginine, asparagine, glutamine, and lysine. We found that all mutations disrupt structure and reduce strength of the collagen fibrils, which may affect the hierarchical packing of the fibrils. The glycine mutations were more detrimental to mechanical strength of the fibrils (WT > Ala > Ser > Cys > Asp) than that of hydroxyproline (WT > Arg > Gln > Asn > Lys). The clinical outcome for glycine mutations agrees well with the trend in reduction of fibril's tensile strength predicted by our simulations. Overall, our results suggest that the reduction in mechanical properties of collagen fibrils may be used to predict the clinical outcome of mutations. Highlights: Black-Right-Pointing-Pointer All mutations disrupt structure and bonding pattern and reduce strength of the collagen fibrils. Black-Right-Pointing-Pointer Gly based mutations are worst to mechanical integrity of fibrils than that of Hyp. Black-Right-Pointing-Pointer Lys and Arg mutations most dramatically destabilize collagen fibril properties. Black-Right-Pointing-Pointer Clinical outcome of mutations may be related to the reduced mechanical properties of fibrils.

  19. Spectrophotometric readout for an alanine dosimeter for food irradiation applications

    International Nuclear Information System (INIS)

    Ebraheem, S.; Beshir, W.B.; Eid, S.; Sobhy, R.; Kovacs, A.

    2003-01-01

    The alanine-electron spin resonance (EPR) readout system is well known as a reference and transfer dosimetry system for the evaluation of high doses in radiation processing. The high cost of an EPR/alanine dosimetry system is a serious handicap for large-scale routine application in irradiation facilities. In this study, the use of a complex produced by dissolving irradiated L-alanine in 1,4-phenyl diammonium dichloride solution was investigated for dosimetry purposes. This complex--having a purple colour--has an increasing absorbance with increasing dose in the range of 1-20 kGy. The applicability of spectrophotometric evaluation was studied by measuring the absorbance intensity of this complex at 360 and 505 nm, respectively. Fluorimetric evaluation was also investigated by measuring the emission of the complex at 435 nm as a function of dose. The present method is easy for routine application. The effect of the dye concentration as well as the suitable amount of irradiated alanine has been studied. With respect to routine application, the stability of the product complex after its formation was also investigated

  20. PGC-1α regulates alanine metabolism in muscle cells.

    Science.gov (United States)

    Hatazawa, Yukino; Qian, Kun; Gong, Da-Wei; Kamei, Yasutomi

    2018-01-01

    The skeletal muscle is the largest organ in the human body, depositing energy as protein/amino acids, which are degraded in catabolic conditions such as fasting. Alanine is synthesized and secreted from the skeletal muscle that is used as substrates of gluconeogenesis in the liver. During fasting, the expression of PGC-1α, a transcriptional coactivator of nuclear receptors, is increased in the liver and regulates gluconeogenesis. In the present study, we observed increased mRNA expression of PGC-1α and alanine aminotransferase 2 (ALT2) in the skeletal muscle during fasting. In C2C12 myoblast cells overexpressing PGC-1α, ALT2 expression was increased concomitant with an increased alanine level in the cells and medium. In addition, PGC-1α, along with nuclear receptor ERR, dose-dependently enhanced the ALT2 promoter activity in reporter assay using C2C12 cells. In the absence of glucose in the culture medium, mRNA levels of PGC-1α and ALT2 increased. Endogenous PGC-1α knockdown in C2C12 cells reduced ALT2 gene expression level, induced by the no-glucose medium. Taken together, in the skeletal muscle, PGC-1α activates ALT2 gene expression, and alanine production may play roles in adaptation to fasting.

  1. Application of an alanine dosimetry system for industrial irradiation and radiation protection

    International Nuclear Information System (INIS)

    Gohs, U.

    1996-01-01

    This paper reports the application of alanine dosimetry in radiation processing. Continuous checks of the EPR measuring conditions as well as using high-quality alanine dosimeters and consistent technique for dose determination guarantee an accuracy of about ± 3% intermediate dose levels. The alanine dosimetry system was applied for dose mapping measurements during irradiator qualification and performance qualification of different products, routine dosimetry, and special radiation protection applications within the gamma irradiator. (author)

  2. Crystallization of glycine with ultrasound

    DEFF Research Database (Denmark)

    Louhi-Kultanen, Marjatta; Karjalainen, Milja; Rantanen, Jukka

    2006-01-01

    Sonocrystallization has proved to be an efficient tool to influence the external appearance and structure of a crystalline product obtained by various crystallization methods. The present work focuses on high intensity sonocrystallization of glycine by varying amplitude of ultrasound with an ultr...... ultrasound power. This study also showed, the higher the ultrasound amplitude the smaller the crystals obtained.......Sonocrystallization has proved to be an efficient tool to influence the external appearance and structure of a crystalline product obtained by various crystallization methods. The present work focuses on high intensity sonocrystallization of glycine by varying amplitude of ultrasound...... with an ultrasound frequency of 20kHz at two temperature ranges 40-50 and 20-30 degrees C in a jacketed 250-ml cooling crystallizer equipped with a stirrer. The polymorph composition of the obtained crystals was analyzed with a temperature variable X-ray powder diffractometer (XRPD). XRPD results showed that...

  3. The binding mechanism of a peptidic cyclic serine protease inhibitor

    DEFF Research Database (Denmark)

    Jiang, Longguang; Svane, Anna Sigrid P.; Sørensen, Hans Peter

    2011-01-01

    Serine proteases are classical objects for studies of catalytic and inhibitory mechanisms as well as interesting as therapeutic targets. Since small-molecule serine protease inhibitors generally suffer from specificity problems, peptidic inhibitors, isolated from phage-displayed peptide libraries......, have attracted considerable attention. Here, we have investigated the mechanism of binding of peptidic inhibitors to serine protease targets. Our model is upain-1 (CSWRGLENHRMC), a disulfide-bond-constrained competitive inhibitor of human urokinase-type plasminogen activator with a noncanonical...... inhibitory mechanism and an unusually high specificity. Using a number of modified variants of upain-1, we characterised the upain-1-urokinase-type plasminogen activator complex using X-ray crystal structure analysis, determined a model of the peptide in solution by NMR spectroscopy, and analysed binding...

  4. Contribution of liver and skeletal muscle to alanine and lactate metabolism in humans

    International Nuclear Information System (INIS)

    Consoli, A.; Nurjhan, N.; Reilly, J.J. Jr.; Bier, D.M.; Gerich, J.E.

    1990-01-01

    To quantitate alanine and lactate gluconeogenesis in postabsorptive humans and to test the hypothesis that muscle is the principal source of these precursors, we infused normal volunteers with [3-14C]lactate, [3-13C]alanine, and [6-3H]glucose and calculated alanine and lactate incorporation into plasma glucose corrected for tricarboxylic acid cycle carbon exchange, the systemic appearance of these substrates, and their forearm fractional extraction, uptake, and release. Forearm alanine and lactate fractional extraction averaged 37 +/- 3 and 27 +/- 2%, respectively; muscle alanine release (2.94 +/- 0.27 mumol.kg body wt-1.min-1) accounted for approximately 70% of its systemic appearance (4.18 +/- 0.31 mumol.kg body wt-1.min-1); muscle lactate release (5.51 +/- 0.42 mumol.kg body wt-1.min-1) accounted for approximately 40% of its systemic appearance (12.66 +/- 0.77 mumol.kg body wt-1.min-1); muscle alanine and lactate uptake (1.60 +/- 0.7 and 3.29 +/- 0.36 mumol.kg body wt-1.min-1, respectively) accounted for approximately 30% of their overall disappearance from plasma, whereas alanine and lactate incorporation into plasma glucose (1.83 +/- 0.20 and 4.24 +/- 0.44 mumol.kg body wt-1.min-1, respectively) accounted for approximately 50% of their disappearance from plasma. We therefore conclude that muscle is the major source of plasma alanine and lactate in postabsorptive humans and that factors regulating their release from muscle may thus exert an important influence on hepatic gluconeogenesis

  5. Kinetic study of carbon dioxide absorption into glycine promoted diethanolamine (DEA)

    Science.gov (United States)

    Pudjiastuti, Lily; Susianto, Altway, Ali; IC, Maria Hestia; Arsi, Kartika

    2015-12-01

    In industry, especially petrochemical, oil and natural gas industry, required separation process of CO2 gas which is a corrosive gas (acid gas). This characteristic can damage the plant utility and piping systems as well as reducing the caloric value of natural gas. Corrosive characteristic of CO2 will appear in areas where there is a decrease in temperature and pressure, such as at the elbow pipe, tubing, cooler and injector turbine. From disadvantages as described above, then it is important to do separation process in the CO2 gas stream, one of the method for remove CO2 from the gas stream is reactive absorption using alkanolamine based solution with promotor. Therefore, this study is done to determine the kinetics constant of CO2 absorption in diethanolamine (DEA) solution using a glycine promoter. Glycine is chosen as a promoter because glycine is a primary amine compound which is reactive, moreover, glycine has resistance to high temperatures so it will not easy to degradable and suitable for application in industry. The method used in this study is absorption using laboratory scale wetted wall column equipment at atmospheric of pressure. This study will to provide the reaction kinetics data information in order to optimize the separation process of CO2 in the industrialized world. The experimental results show that rising temperatures from 303,15 - 328,15 K and the increase of concentration of glycine from 1% - 3% weight will increase the absorption rate of carbon dioxide in DEA promoted with glycine by 24,2% and 59,764% respectively, also the reaction kinetic constant is 1.419 × 1012 exp (-3634/T) (m3/kmol.s). This result show that the addition of glycine as a promoter can increase absorption rate of carbon dioxide in diethanolamine solution and cover the weaknesses of diethanolamine solution.

  6. Sublethal and hormesis effects of imidacloprid on the soybean aphid Aphis glycines.

    Science.gov (United States)

    Qu, Yanyan; Xiao, Da; Li, Jinyu; Chen, Zhou; Biondi, Antonio; Desneux, Nicolas; Gao, Xiwu; Song, Dunlun

    2015-04-01

    The soybean aphid, Aphis glycines Matsumura, is a major pest in soybean crop. Current management of this pest relies mainly on insecticides applications, and the neonicotinoid imidacloprid has been proposed as an effective insecticide to control A. glycines in soybean field. Imidacloprid at lethal concentrations not only exerts acute toxicity to A. glycines, but also cause various biological changes when aphids are chronically exposed to lower concentrations. In this study, we assessed the effects of a low-lethal (0.20 mg L(-1)) and two sublethal (0.05 and 0.10 mg L(-1)) imidacloprid concentrations on various A. glycines life history traits. Aphid exposure to 0.20 mg L(-1) imidacloprid caused slower juvenile development, shorter reproductive period, and reduced adult longevity, fecundity and total lifespan. Stimulatory effects, i.e. hormesis, on reproduction and immature development duration were observed in aphids exposed to the lower sublethal imidacloprid concentrations. Consequently, the net reproduction rate (R 0) was significantly higher than in the control aphids. These findings stress the importance of the actual imidacloprid concentration in its toxicological properties on A. glycines. Therefore, our results would be useful for assessing the overall effects of imidacloprid on A. glycines and for optimizing integrated pest management programs targeting this pest.

  7. Cell-type specific mechanisms of D-serine uptake and release in the brain

    Directory of Open Access Journals (Sweden)

    Magalie eMartineau

    2014-05-01

    Full Text Available Accumulating evidence during the last decade established that D-serine is a key signaling molecule utilized by neurons and astroglia in the mammalian central nervous system. D-serine is increasingly appreciated as the main physiological endogenous coagonist for synaptic NMDA receptors at central excitatory synapses; it is mandatory for long-term changes in synaptic strength, memory, learning, and social interactions. Alterations in the extracellular levels of D-serine leading to disrupted cell-cell signaling are a trademark of many chronic or acute neurological (i.e. Alzheimer disease, epilepsy, stroke and psychiatric (i.e. schizophrenia disorders, and are associated with addictive behavior (i.e. cocaine addiction. Indeed, fine tuning of the extracellular levels of D-serine, achieved by various molecular machineries and signaling pathways, is necessary for maintenance of accurate NMDA receptor functions. Here, we review the experimental data supporting the notion that astroglia and neurons use different pathways to regulate levels of extracellular D-serine.

  8. Earthworms accumulate alanine in response to drought.

    Science.gov (United States)

    Holmstrup, Martin; Slotsbo, Stine; Henriksen, Per G; Bayley, Mark

    2016-09-01

    Earthworms have ecologically significant functions in tropical and temperate ecosystems and it is therefore important to understand how these animals survive during drought. In order to explore the physiological responses to dry conditions, we simulated a natural drought incident in a laboratory trial exposing worms in slowly drying soil for about one month, and then analyzed the whole-body contents of free amino acids (FAAs). We investigated three species forming estivation chambers when soils dry out (Aporrectodea tuberculata, Aporrectodea icterica and Aporrectodea longa) and one species that does not estivate during drought (Lumbricus rubellus). Worms subjected to drought conditions (alanine that was significantly upregulated in all tested species. Alanine was the most important FAA reaching 250-650μmolg(-1) dry weight in dehydrated Aporrectodea species and 300μmolg(-1) dry weight in L. rubellus. Proline was only weakly upregulated in some species as were a few other FAAs. Species forming estivation chambers (Aporrectodea spp.) did not show a better ability to conserve body water than the non-estivating species (L. rubellus) at the same drought level. These results suggest that the accumulation of alanine is an important adaptive trait in drought tolerance of earthworms in general. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Characteristics and application of alanine dosimeter 'Aminogray'

    International Nuclear Information System (INIS)

    Kashiwazaki, Shigeru; Matsuyama, Shigeki; Hatta, Toshimasa; Yagyu, Hideki; Kojima, Takuji; Tanaka, Ryuichi; Morita, Yohsuke.

    1988-01-01

    Recently, accompanying the progress of nuclear power generation and space development, the evaluation of reliability for the materials and parts used under irradiation has become important. For the evaluation of reliability, the accurate grasp of radiation dose is the prerequisite. In some case, the measurement of cumulative dose in a long period in an actual environment becomes necessary. In this paper, the characteristics and application of a new dosimeter element 'Aminogray' which is suitable to the above requirement are reported. Aminogray is rodshape element made by forming alanine, a kind of amino acid, using a binder polymer, and the alanine content is 70 wt.%, and the polymer is polystyrene. An element of 3 mm diameter and 30 mm length is enclosed in a polystyrene cylinder of 4 mm thickness. This thickness was determined by considering the electronic equilibrium condition in Co-60 gamma-ray irradiation. The principle of the measurement is to determine a dose by measuring the amount of free radicals produced in alanine by radiation using ESR method. The free radicals are extremely stable, and exist for a long period, and the amount of radical production is proportional to absorbed dose. The development, characteristics and application of Aminogray are reported. (K.I.)

  10. Regulation of the ald Gene Encoding Alanine Dehydrogenase by AldR in Mycobacterium smegmatis

    Science.gov (United States)

    Jeong, Ji-A; Baek, Eun-Young; Kim, Si Wouk; Choi, Jong-Soon

    2013-01-01

    The regulatory gene aldR was identified 95 bp upstream of the ald gene encoding l-alanine dehydrogenase in Mycobacterium smegmatis. The AldR protein shows sequence similarity to the regulatory proteins of the Lrp/AsnC family. Using an aldR deletion mutant, we demonstrated that AldR serves as both activator and repressor for the regulation of ald gene expression, depending on the presence or absence of l-alanine. The purified AldR protein exists as a homodimer in the absence of l-alanine, while it adopts the quaternary structure of a homohexamer in the presence of l-alanine. The binding affinity of AldR for the ald control region was shown to be increased significantly by l-alanine. Two AldR binding sites (O1 and O2) with the consensus sequence GA-N2-ATC-N2-TC and one putative AldR binding site with the sequence GA-N2-GTT-N2-TC were identified upstream of the ald gene. Alanine and cysteine were demonstrated to be the effector molecules directly involved in the induction of ald expression. The cellular level of l-alanine was shown to be increased in M. smegmatis cells grown under hypoxic conditions, and the hypoxic induction of ald expression appears to be mediated by AldR, which senses the intracellular level of alanine. PMID:23749971

  11. The effects of glycine on subjective daytime performance in partially sleep-restricted healthy volunteers

    Directory of Open Access Journals (Sweden)

    Makoto eBannai

    2012-04-01

    Full Text Available Approximately 30% of the general population suffers from insomnia. Given that insomnia causes many problems, amelioration of the symptoms is crucial. Recently, we found that a nonessential amino acid, glycine subjectively and objectively improves sleep quality in humans who have difficulty sleeping. We evaluated the effects of glycine on daytime sleepiness, fatigue and performances in sleep-restricted healthy subjects. Sleep was restricted to 25% less than the usual sleep time for three consecutive nights. Before bedtime, 3 g of glycine or placebo were ingested, sleepiness and fatigue were evaluated using the visual analogue scale (VAS and a questionnaire, and performance were estimated by personal computer (PC performance test program on the following day. In subjects given glycine, the VAS data showed a significant reduction in fatigue and a tendency toward reduced sleepiness. These observations were also found via the questionnaire, indicating that glycine improves daytime sleepiness and fatigue induced by acute sleep restriction. PC performance test revealed significant improvement in psychomotor vigilance test. We also measured plasma melatonin and the expression of circadian-modulated genes expression in the rat suprachiasmatic nucleus (SCN to evaluate the effects of glycine on circadian rhythms. Glycine did not show significant effects on plasma melatonin concentrations during either the dark or light period. Moreover, the expression levels of clock genes such as Bmal1 and Per2 remained unchanged. However, we observed a glycine-induced increase in the neuropeptides arginine vasopressin and vasoactive intestinal polypeptide in the light period. Although no alterations in the circadian clock itself were observed, our results indicate that glycine modulated SCN function. Thus, glycine modulates certain neuropeptides in the SCN and this phenomenon may indirectly contribute to improving the occasional sleepiness and fatigue induced by sleep

  12. No effect of β-alanine on muscle function and kayak performance

    DEFF Research Database (Denmark)

    Bech, Signe Refsgaard; Nielsen, Tobias Schmidt; Hald, Martin

    2018-01-01

    PURPOSE: It was investigated if β-alanine supplementation counteracts muscular fatigue development or improves athletic performance. METHODS: Elite kayak rowers (10 males and 7 females) were supplemented with either 80 mg/kg body mass/day β-alanine or placebo for 8 weeks. Muscular fatigue...

  13. Effect of β-alanine supplementation on 20 km cycling time trial performance

    Directory of Open Access Journals (Sweden)

    Ruth Margaret JAMES

    2014-09-01

    Full Text Available The effects of β-alanine supplementation on high-intensity cycling performance and capacity have been evaluated, although the effects on longer duration cycling performance are unclear. Nineteen UK category 1 male cyclists completed four 20 km cycling time trials, two before and two after supplementation with either 6.4 g•d-1 β-alanine (n = 10; BA or a matched placebo (n = 9; P. Performance time for the 20 km time trial and 1 km split times were recorded. There was no significant effect of β-alanine supplementation on 20 km time trial performance (BA-pre 1943 ± 129 s; BA-post 1950 ± 147 s; P-pre 1989 ± 106 s; P-post 1986 ± 115 s or on the performance of each 1 km split. The effect of β-alanine on 20 km time trial performance was deemed unclear as determined by magnitude based inferences. Supplementation with 6.4 g•d-1 of β-alanine for 4 weeks did not affect 20 km cycling time trial performance in well trained male cyclists.

  14. Cloning and sequence analysis of serine proteinase of Gloydius ussuriensis venom gland

    International Nuclear Information System (INIS)

    Sun Dejun; Liu Shanshan; Yang Chunwei; Zhao Yizhuo; Chang Shufang; Yan Weiqun

    2005-01-01

    Objective: To construct a cDNA library by using mRNA from Gloydius ussuriensis (G. Ussuriensis) venom gland, to clone and analyze serine proteinase gene from the cDNA library. Methods: Total RNA was isolated from venom gland of G. ussuriensis, mRNA was purified by using mRNA isolation Kit. The whole length cDNA was synthesized by means of smart cDNA synthesis strategy, and amplified by long distance PCR procedure, lately cDAN was cloned into vector pBluescrip-sk. The recombinant cDNA was transformed into E. coli DH5α. The cDNA of serine proteinase gene in the venom gland of G. ussuriensis was detected and amplified using the in situ hybridization. The cDNA fragment was inserted into pGEMT vector, cloned and its nucleotide sequence was determined. Results: The capacity of cDNA library of venom gland was above 2.3 x 10 6 . Its open reading frame was composed of 702 nucleotides and coded a protein pre-zymogen of 234 amino acids. It contained 12 cysteine residues. The sequence analysis indicated that the deduced amino acid sequence of the cDNA fragment shared high identity with the thrombin-like enzyme genes of other snakes in the GenBank. the query sequence exhibited strong amino acid sequence homology of 85% to the serine proteas of T. gramineus, thrombin-like serine proteinase I of D. acutus and serine protease catroxase II of C. atrox respectively. Based on the amino acid sequences of other thrombin-like enzymes, the catalytic residues and disulfide bridges of this thrombin-like enzyme were deduced as follows: catalytic residues, His 41 , Asp 86 , Ser 180 ; and six disulfide bridges Cys 7 -Cys 139 , Cys 26 -Cys 42 , Cys 74 -Cys 232 , Cys 118 -Cys 186 , Cys 150 -Cys 165 , Cys 176 -Cys 201 . Conclusion: The capacity of cDNA library of venom gland is above 2.3 x 10 6 , overtop the level of 10 5 capicity. The constructed cDNA library of G. ussuriensis venom gland would be helpful platform to detect new target genes and further gene manipulate. The cloned serine

  15. l-Serine Enhances Light-Induced Circadian Phase Resetting in Mice and Humans.

    Science.gov (United States)

    Yasuo, Shinobu; Iwamoto, Ayaka; Lee, Sang-Il; Ochiai, Shotaro; Hitachi, Rina; Shibata, Satomi; Uotsu, Nobuo; Tarumizu, Chie; Matsuoka, Sayuri; Furuse, Mitsuhiro; Higuchi, Shigekazu

    2017-12-01

    Background: The circadian clock is modulated by the timing of ingestion or food composition, but the effects of specific nutrients are poorly understood. Objective: We aimed to identify the amino acids that modulate the circadian clock and reset the light-induced circadian phase in mice and humans. Methods: Male CBA/N mice were orally administered 1 of 20 l-amino acids, and the circadian and light-induced phase shifts of wheel-running activity were analyzed. Antagonists of several neurotransmitter pathways were injected before l-serine administration, and light-induced phase shifts were analyzed. In addition, the effect of l-serine on the light-induced phase advance was investigated in healthy male students (mean ± SD age 22.2 ± 1.8 y) by using dim-light melatonin onset (DLMO) determined by saliva samples as an index of the circadian phase. Results: l-Serine administration enhanced light-induced phase shifts in mice (1.86-fold; P light-dark cycle by 6 h, l-serine administration slightly accelerated re-entrainment to the shifted cycle. In humans, l-serine ingestion before bedtime induced significantly larger phase advances of DLMO after bright-light exposure during the morning (means ± SEMs-l-serine: 25.9 ± 6.6 min; placebo: 12.1 ± 7.0 min; P light-induced phase resetting in mice and humans, and it may be useful for treating circadian disturbances. © 2017 American Society for Nutrition.

  16. G3.5 PAMAM dendrimers enhance transepithelial transport of SN38 while minimizing gastrointestinal toxicity.

    Science.gov (United States)

    Goldberg, Deborah S; Vijayalakshmi, Nirmalkumar; Swaan, Peter W; Ghandehari, Hamidreza

    2011-03-30

    Poly(amido amine) (PAMAM) dendrimers have shown promise in oral drug delivery. Conjugation of SN38 to PAMAM dendrimers has the potential to improve its oral absorption while minimizing gastrointestinal toxicity. In this work we evaluated G3.5 PAMAM dendrimer-SN38 conjugates with ester-linked glycine and β-alanine spacers for their suitability in oral therapy of hepatic colorectal cancer metastases. G3.5-βAlanine-SN38 was mostly stable while G3.5-Glycine-SN38 showed 10%, 20%, and 56% SN38 release in simulated gastric, intestinal and liver environments for up to 6, 24 and 48 hours, respectively. Short-term treatment of Caco-2 cells with G3.5-SN38 conjugates did not reduce cell viability, while comparable concentrations of SN38 caused significant cytotoxicity. G3.5-Glycine-SN38 and G3.5-βAlanine-SN38 showed IC₅₀ values of 0.60 and 3.59 μM, respectively, in HT-29 cells treated for 48 h, indicating the efficacy of the drug delivery system in colorectal cancer cells with longer incubation time. Both conjugates increased SN38 transepithelial transport compared to the free drug. Transport of G3.5-Glycine-SN38 was highly concentration-dependent whereas transport of G3.5-βAlanine-SN38 was concentration-independent, highlighting the influence of drug loading and spacer chemistry on transport mechanism. Together these results show that PAMAM dendrimers have the potential to improve the oral bioavailability of potent anti-cancer drugs. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Localization of high affinity [3H]glycine transport sites in the cerebellar cortex

    International Nuclear Information System (INIS)

    Wilkin, G.P.; Csillag, A.; Balazs, R.; Kingsbury, A.E.; Wilson, J.E.; Johnson, A.L.

    1981-01-01

    A study was made of [ 3 H ]glycine uptake sites in a preparation greatly enriched in large pieces of the cerebellar glomeruli (glomerulus particles) and in morphologically well preserved slices of rat cerebellum. Electron microscopic autoradiography revealed that of the neurones in the cerebellar cortex only Golgi cells transported [ 3 H]glycine at the low concentration used. Glial cells also took up [ 3 H]glycine but to a lesser extent than the Golgi neurons. It was also confirmed that under comparable conditions Golgi cells transport [ 3 H]GABA. Kinetic studies utilizing the Golgi axon terminal-containing glomerulus particles showed that glycine is a weak non-competitive inhibitor of [ 3 H]GABA uptake (Ksub(i) over 600 μM vs the Ksub(t) of about 20 μM) and that GABA is an even weaker inhibitor of [ 3 H]glycine uptake. (Auth.)

  18. Effect of Glycine on Lead Mobilization, Lead-Induced Oxidative Stress, and Hepatic Toxicity in Rats

    Directory of Open Access Journals (Sweden)

    Yolanda Alcaraz-Contreras

    2011-01-01

    Full Text Available The effectiveness of glycine in treating experimental lead intoxication was examined in rats. Male Wistar rats were exposed to 3 g/L lead acetate in drinking water for 5 weeks and treated thereafter with glycine (100 and 500 mg/kg, orally once daily for 5 days or glycine (1000 mg/kg, orally once daily for 28 days. The effect of these treatments on parameters indicative of oxidative stress (glutathione and malondialdehyde levels, the activity of blood -aminolevulinic acid dehydratase, and lead concentration in blood, liver, kidney, brain, and bone were investigated. Liver samples were observed for histopathological changes. Glycine was found to be effective in (1 increasing glutathione levels; (2 reducing malondialdehyde levels; (3 decreasing lead levels in bone with the highest dose. However, glycine had no effect on lead mobilization when 100 and 500 mg/kg glycine were administered. In microscopic examination, glycine showed a protective effect against lead intoxication.

  19. ESR/Alanine {gamma}-dosimetry in the 10-30 Gy range

    Energy Technology Data Exchange (ETDEWEB)

    Fainstein, C. E-mail: cfainstein@cab.cnea.gov.ar; Winkler, E.; Saravi, M

    2000-05-15

    We report Alanine Dosimeter preparation, procedures for using the ESR/Dosimetry method, and the resulting calibration curve for {gamma}-irradiation in the range from 10-30 Gy. We use calibration curve to measure the irradiation dose in {gamma}-irradiation of human blood, as required in Blood Transfusion Therapy. The ESR/Alanine results are compared against those obtained using the thermoluminescent dosimetry (TLD) method.

  20. Kinetics and mechanism of oxidation of glycine by iron(III)

    Indian Academy of Sciences (India)

    Kinetics and mechanism of oxidation of glycine by iron(III)-1,10-phenanthroline complex has been studied in perchloric acid medium. The reaction is first order with respect to iron(III) and glycine. An increase in (phenanthroline) increases the rate, while increase in [H+] decreases the rate. Hence it can be inferred that the ...

  1. Dosage compensation of serine-4 transfer RNA in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Birchler, J.A.; Owenby, R.K.; Jacobson, K.B.

    1982-01-01

    A dosage series of the X chromosome site for serine-4 transfer RNA consisting of one of three copies in females and one to two in males was constructed to test whether transfer RNA expression is governed by dosage compensation. A dosage effect on the level of the serine-4 isoacceptor was observed in both females and males when the structural locus was varied. However, in males, each dose had a relatively greater expression so the normal one dose was slightly greater than the total female value and the duplicated male had the highest relative expression of all the types examined. Serine-4 levels in males and females from an isogenic Oregon-R stock were similar. Thus the transfer RNA levels conform to the expectations of dosage compensation

  2. Inducible l-Alanine Exporter Encoded by the Novel Gene ygaW (alaE) in Escherichia coli ▿

    Science.gov (United States)

    Hori, Hatsuhiro; Yoneyama, Hiroshi; Tobe, Ryuta; Ando, Tasuke; Isogai, Emiko; Katsumata, Ryoichi

    2011-01-01

    We previously isolated a mutant hypersensitive to l-alanyl-l-alanine from a non-l-alanine-metabolizing Escherichia coli strain and found that it lacked an inducible l-alanine export system. Consequently, this mutant showed a significant accumulation of intracellular l-alanine and a reduction in the l-alanine export rate compared to the parent strain. When the mutant was used as a host to clone a gene(s) that complements the dipeptide-hypersensitive phenotype, two uncharacterized genes, ygaW and ytfF, and two characterized genes, yddG and yeaS, were identified. Overexpression of each gene in the mutant resulted in a decrease in the intracellular l-alanine level and enhancement of the l-alanine export rate in the presence of the dipeptide, suggesting that their products function as exporters of l-alanine. Since ygaW exhibited the most striking impact on both the intra- and the extracellular l-alanine levels among the four genes identified, we disrupted the ygaW gene in the non-l-alanine-metabolizing strain. The resulting isogenic mutant showed the same intra- and extracellular l-alanine levels as observed in the dipeptide-hypersensitive mutant obtained by chemical mutagenesis. When each gene was overexpressed in the wild-type strain, which does not intrinsically excrete alanine, only the ygaW gene conferred on the cells the ability to excrete alanine. In addition, expression of the ygaW gene was induced in the presence of the dipeptide. On the basis of these results, we concluded that YgaW is likely to be the physiologically most relevant exporter for l-alanine in E. coli and proposed that the gene be redesignated alaE for alanine export. PMID:21531828

  3. New Generation of self-calibrated SS/EPR dosimeters: Alanine/EPR dosimeters

    International Nuclear Information System (INIS)

    Yordanov, N.D.; Gancheva, V.

    1999-01-01

    A new type of solid state/EPR dosimeters is described. Principally, it contains radiation sensitive diamagnetic material, some quantity of EPR active, but radiation insensitive, substance (for example Mn 2+ /MgO) and a binding material. In the present case alanine is used as a radiation sensitive substance. With this dosimeter, the EPR spectra of alanine and Mn 2+ are simultaneously recorded and the calibration graph represents the ratio of alanine versus Mn 2+ EPR signal intensity as a function of absorbed dose. In this way the reproducibility of the results is expected to be improved significantly including their intercomparison among different laboratories. Homogeneity of the prepared dosimeters and their behaviour (fading of EPR signals with time, influence of different meteorological conditions) show satisfactory reproducibility and stability with time. Because two different EPR active samples are recorded simultaneously, the influence of some instrument setting parameters (microwave power, modulation amplitude and modulation frequency) on the ratio I alanine /I Mn is also investigated. (author)

  4. Effect of combined β-alanine and sodium bicarbonate supplementation on cycling performance.

    Science.gov (United States)

    Bellinger, Phillip M; Howe, Samuel T; Shing, Cecilia M; Fell, James W

    2012-08-01

    The purpose of this study was to investigate the effects of 28 d of β-alanine supplementation on 4-min cycling time trial performance and to determine whether there was an additive effect of combined β-alanine and sodium bicarbonate (NaHCO3) supplementation on high-intensity cycling performance. Fourteen highly trained cyclists (mean ± SD: age = 25.4 ± 7.2 yr, mass = 71.1 ± 7.1 kg, V˙O(2max) = 66.6 ± 5.7 mL·kg·min) supplemented for 28 d with β-alanine (65 mg·kg body mass each day) or placebo. A maximal 4-min bout of cycling was performed before supplementation (baseline) and twice after supplementation: after ingestion of NaHCO3 (300 mg·kg body mass) and ingestion of a placebo using a randomized crossover design with 2 d between trials. Blood pH and HCO3 concentration were determined before loading (postsupplementation trials) and at pretest and posttest. In the acute NaHCO3 loading trials, blood pH and HCO3 were elevated from before loading to pretest, and the magnitude of the change in HCO3 from pretest to posttest was significantly greater compared with the acute placebo loading trial (P < 0.001). Average power output in the 4-min cycling performance trial was increased in placebo + NaHCO3 (+3.1% ± 1.8%) and β-alanine + NaHCO3 (+3.3% ± 3.0%) compared with baseline (P < 0.05). β-alanine + placebo did not significantly improve average power output compared with baseline (+1.6% ± 1.7%, P = 0.20); however, magnitude-based inferences demonstrated that β-alanine + placebo was associated with a 37% likelihood of producing average power improvements. In trained cyclists, β-alanine supplementation did not significantly improve 4-min cycling performance; however, there may be a small meaningful improvement in performance. Acute NaHCO3 supplementation significantly improved 4-min cycling performance. There seemed to be a minimal additive effect of combined β-alanine and NaHCO3 supplementation.

  5. SU-E-T-643: Pure Alanine Dosimeter for Verification Dosimetry in IMRT

    International Nuclear Information System (INIS)

    Al-Karmi, Anan M.; Zraiqat, Fadi

    2015-01-01

    Purpose: The objective of this study was evaluation of accuracy of pure alanine dosimeters measuring intensity-modulated radiation therapy (IMRT) dose distributions in a thorax phantom. Methods: Alanine dosimeters were prepared in the form of 110 mg pure L-α-alanine powder filled into clear tissue-equivalent polymethylmethacrylate (PMMA) plastic tubes with the dimensions 25 mm length, 3 mm inner diameter, and 1 mm wall thickness. A dose-response calibration curve was established for the alanine by placing the dosimeters at 1.5 cm depth in a 30×30×30 cm 3 solid water phantom and then irradiating on a linac with 6 MV photon beam at 10×10 cm 2 field size to doses ranging from 1 to 5 Gy. Electron paramagnetic resonance (EPR) spectroscopy was used to determine the absorbed dose in alanine. An IMRT treatment plan was designed for a commercial heterogeneous CIRS thorax phantom and the dose values were calculated at three different points located in tissue, lung, and bone equivalent materials. A set of dose measurements was carried out to compare measured and calculated dose values by placing the alanine dosimeters at those selected locations inside the thorax phantom and delivering the IMRT to the phantom. Results: The alanine dose measurements and the IMRT plan dose calculations were found to be in agreement within ±2%. Specifically, the deviations were −0.5%, 1.3%, and −1.7% for tissue, lung, and bone; respectively. The slightly large deviations observed for lung and bone may be attributed to tissue inhomogeneity, steep dose gradients in these regions, and uncontrollable changes in spectrometer conditions. Conclusion: The results described herein confirmed that pure alanine dosimeter was suitable for in-phantom dosimetry of IMRT beams because of its high sensitivity and acceptable accuracy. This makes the dosimeter a promising option for quality control of the therapeutic beams, complementing the commonly used ionization chambers, TLDs, and films

  6. Equilibria in aqueous cadmium-chloroacetate-glycinate systems. A convolution-deconvolution cyclic voltammetric study

    International Nuclear Information System (INIS)

    Abdel-Hamid, R.; Rabia, M.K.M.

    1994-01-01

    Stability constants and composition of cadmium-glycinate binary complexes were determined using cyclic voltammetry. Furthermore, binary and ternary complex equilibria for chloroacetates and glycinate with cadmium in 0.1 M aqueous KNO 3 at pH 10.4 and 298 K were investigated. Cadmium forms binary complexes with chloroacetates of low stability and ternary ones with chloroacetate-glycinate of significant stability. (author)

  7. Purification and characterization of an iron-induced ferritin from soybean (Glycine max) cell suspensions.

    Science.gov (United States)

    Lescure, A M; Massenet, O; Briat, J F

    1990-11-15

    Ferric citrate induces ferritin synthesis and accumulation in soybean (Glycine max) cell suspension cultures [Proudhon, Briat & Lescure (1989) Plant Physiol. 90, 586-590]. This iron-induced ferritin has been purified from cells grown for 72 h in the presence of either 100 microM- or 500 microM-ferric citrate. It has a molecular mass of about 600 kDa and is built up from a 28 kDa subunit which is recognized by antibodies raised against pea (Pisum sativum) seed ferritin and it has the same N-terminal sequence as this latter, except for residue number 3, which is alanine in pea seed ferritin instead of valine in iron-induced soybean cell ferritin. It contains an average of 1800 atoms of iron per molecule whatever the ferric citrate concentration used to induce its synthesis. It is shown that the presence of 100 microM- or 500 microM-ferric citrate in the culture medium leads respectively to an 11- and 28-fold increase in the total intracellular iron concentration and to a 30- and 60-fold increase in the ferritin concentration. However, the percentage of iron stored in the mineral core of ferritin remains constant whatever the ferric citrate concentration used and represents only 5-6% of cellular iron.

  8. Secondary Emission From Synthetic Opal Infiltrated by Colloidal Gold and Glycine

    International Nuclear Information System (INIS)

    Dovbeshko, G.I.; Fesenko, O.M.; Boyko, V.V.; Romanyuk, V.R.; Gorelik, V.S.; Moiseyenko, V.N.; Sobolev, V.B.; Shvalagin, V.V.

    2012-01-01

    A comparison of the secondary emission (photoluminescence) and Bragg reflection spectra of photonic crystals (PC), namely, synthetic opals, opals infiltrated by colloidal gold, glycine, and a complex of colloidal gold with glycine is performed. The infiltration of colloidal gold and a complex of colloidal gold with glycine into the pores of PC causes a short-wavelength shift (about 5-15 nm) of the Bragg reflection and increases the intensity of this band by 1.5-3 times. In photoluminescence, the infiltration of PC by colloidal gold and colloidal gold with glycine suppresses the PC emission band near 375-450 nm and enhances the shoulder of the stop-zone band of PC in the region of 470-510 nm. The shape of the observed PC emission band connected with defects in synthetic opal is determined by the type of infiltrates and the excitation wavelength. Possible mechanisms of the effects are discussed.

  9. VanT, a homologue of Vibrio harveyi LuxR, regulates serine, metalloprotease, pigment, and biofilm production in Vibrio anguillarum.

    Science.gov (United States)

    Croxatto, Antony; Chalker, Victoria J; Lauritz, Johan; Jass, Jana; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L

    2002-03-01

    Vibrio anguillarum possesses at least two N-acylhomoserine lactone (AHL) quorum-sensing circuits, one of which is related to the luxMN system of Vibrio harveyi. In this study, we have cloned an additional gene of this circuit, vanT, encoding a V. harveyi LuxR-like transcriptional regulator. A V. anguillarum Delta vanT null mutation resulted in a significant decrease in total protease activity due to loss of expression of the metalloprotease EmpA, but no changes in either AHL production or virulence. Additional genes positively regulated by VanT were identified from a plasmid-based gene library fused to a promoterless lacZ. Three lacZ fusions (serA::lacZ, hpdA-hgdA::lacZ, and sat-vps73::lacZ) were identified which exhibited decreased expression in the Delta vanT strain. SerA is similar to 3-phosphoglycerate dehydrogenases and catalyzes the first step in the serine-glycine biosynthesis pathway. HgdA has identity with homogentisate dioxygenases, and HpdA is homologous to 4-hydroxyphenylpyruvate dioxygenases (HPPDs) involved in pigment production. V. anguillarum strains require an active VanT to produce high levels of an L-tyrosine-induced brown color via HPPD, suggesting that VanT controls pigment production. Vps73 and Sat are related to Vibrio cholerae proteins encoded within a DNA locus required for biofilm formation. A V. anguillarum Delta vanT mutant and a mutant carrying a polar mutation in the sat-vps73 DNA locus were shown to produce defective biofilms. Hence, a new member of the V. harveyi LuxR transcriptional activator family has been characterized in V. anguillarum that positively regulates serine, metalloprotease, pigment, and biofilm production.

  10. Evaluation of oxidative stress in D-serine induced nephrotoxicity

    International Nuclear Information System (INIS)

    Orozco-Ibarra, Marisol; Medina-Campos, Omar Noel; Sanchez-Gonzalez, Dolores Javier; Martinez-Martinez, Claudia Maria; Floriano-Sanchez, Esau; Santamaria, Abel; Ramirez, Victoria; Bobadilla, Norma A.; Pedraza-Chaverri, Jose

    2007-01-01

    It has been suggested that oxidative stress is involved in D-serine-induced nephrotoxicity. The purpose of this study was to assess if oxidative stress is involved in this experimental model using several approaches including (a) the determination of several markers of oxidative stress and the activity of some antioxidant enzymes in kidney and (b) the use of compounds with antioxidant or prooxidant effects. Rats were sacrificed at several periods of time (from 3 to 24 h) after a single i.p. injection of D-serine (400 mg/kg). Control rats were injected with L-serine (400 mg/kg) and sacrificed 24 h after. The following markers were used to assess the temporal aspects of renal damage: (a) urea nitrogen (BUN) and creatinine in blood serum, (b) kidney injury molecule (KIM-1) mRNA levels, and (c) tubular necrotic damage. In addition, creatinine clearance, proteinuria, and urinary excretion of N-acetyl-β-D-glucosaminidase (NAG) were measured 24 h after D-serine injection. Protein carbonyl content, malondialdehyde (MDA), 4-hydroxy-2-nonenal (4-HNE), fluorescent products of lipid peroxidation, reactive oxygen species (ROS), glutathione (GSH) content, and heme oxygenase-1 (HO-1) expression were measured as markers of oxidative stress in the kidney. Additional experiments were performed using the following compounds with antioxidant or pro-oxidant effects before D-serine injection: (a) α-phenyl-tert-butyl-nitrone (PBN), a spin trapping agent; (b) 5,10,15,20-tetrakis (4-sulfonatophenyl) porphyrinato iron(III) (FeTPPS), a soluble complex able to metabolize peroxynitrite; (c) aminotriazole (ATZ), a catalase (CAT) inhibitor; (d) stannous chloride (SnCl 2 ), an HO-1 inductor; (e) tin mesoporphyrin (SnMP), an HO inhibitor. In the time-course study, serum creatinine and BUN increased significantly on 15-24 and 20-24 h, respectively, and KIM-1 mRNA levels increased significantly on 6-24 h. Histological analyses revealed tubular necrosis at 12 h. The activity of antioxidant enzymes

  11. The Alanine Racemase of Mycobacterium smegmatis Is Essential for Growth in the Absence of d-Alanine▿ †

    Science.gov (United States)

    Milligan, Daniel L.; Tran, Sieu L.; Strych, Ulrich; Cook, Gregory M.; Krause, Kurt L.

    2007-01-01

    Alanine racemase, encoded by the gene alr, is an important enzyme in the synthesis of d-alanine for peptidoglycan biosynthesis. Strains of Mycobacterium smegmatis with a deletion mutation of the alr gene were found to require d-alanine for growth in both rich and minimal media. This indicates that alanine racemase is the only source of d-alanine for cell wall biosynthesis in M. smegmatis and confirms alanine racemase as a viable target gene for antimycobacterial drug development. PMID:17827284

  12. Dextran Sulfate Sodium Inhibits Alanine Synthesis in Caco-2 Cells

    Directory of Open Access Journals (Sweden)

    Carolyn M. Slupsky

    2011-04-01

    Full Text Available To understand and characterize the pathogenic mechanisms of inflammatory bowel disease, dextran sulfate sodium (DSS has been used to induce acute and chronic colitis in animal models by causing intestinal epithelium damage. The mechanism of action of DSS in producing this outcome is not well understood. In an effort to understand how DSS might impact epithelial cell metabolism, we studied the intestinal epithelial cell line Caco-2 incubated with 1% DSS over 56 hours using 1H NMR spectroscopy. We observed no difference in cell viability as compared to control cultures, and an approximately 1.5-fold increase in IL-6 production upon incubation with 1% DSS. The effect on Caco-2 cell metabolism as measured through changes in the concentration of metabolites in the cell supernatant included a three-fold decrease in the concentration of alanine. Given that the concentrations of other amino acids in the cell culture supernatant were not different between treated and control cultures over 56 hours suggest that DSS inhibits alanine synthesis, specifically alanine aminotransferase, without affecting other key metabolic pathways. The importance of alanine aminotransferase in inflammatory bowel disease is discussed.

  13. Synthesis, characterization, and biocompatible properties of alanine-grafted chitosan copolymers.

    Science.gov (United States)

    Park, Gyu Han; Kang, Min-Sil; Knowles, Jonathan C; Gong, Myoung-Seon

    2016-04-01

    In order to overcome major problems regarding the lack of affinity to solvents and limited reactivity of the free amines of chitosan, introduction of appropriate spacer arms having terminal amine function is considered of interest. L-Alanine-N-carboxyanhydride was grafted onto chitosan via anionic ring-opening polymerization. The chemical and structural characterizations of L-alanine-grafted chitosan (Ala-g-Cts) were confirmed through Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy ((1)H NMR). In addition, the viscoelastic properties of Ala-g-Cts were examined by means of a rotational viscometer, and thermal analysis was carried out with a thermogravimetric analyzer and differential scanning calorimetry. Morphological changes in the chitosan L-alanine moiety were determined by x-ray diffraction. To determine the feasibility of using these films as biomedical materials, we investigated the effects of their L-alanine content on physical and mechanical properties. The biodegradation results of crosslinked Ala-g-Cts films were evaluated in phosphate-buffered solution containing lysozyme at 37℃. Proliferation of MC3T3-E1 cells on crosslinked Ala-g-Cts films was also investigated with use of the CCK-8 assay. © The Author(s) 2016.

  14. Gbu Glycine Betaine Porter and Carnitine Uptake in Osmotically Stressed Listeria monocytogenes Cells

    Science.gov (United States)

    Mendum, Mary Lou; Smith, Linda Tombras

    2002-01-01

    The food-borne pathogen Listeria monocytogenes grows actively under high-salt conditions by accumulating compatible solutes such as glycine betaine and carnitine from the medium. We report here that the dominant transport system for glycine betaine uptake, the Gbu porter, may act as a secondary uptake system for carnitine, with a Km of 4 mM for carnitine uptake and measurable uptake at carnitine concentrations as low as 10 μM. This porter has a Km for glycine betaine uptake of about 6 μM. The dedicated carnitine porter, OpuC, has a Km for carnitine uptake of 1 to 3 μM and a Vmax of approximately 15 nmol/min/mg of protein. Mutants lacking either opuC or gbu were used to study the effects of four carnitine analogs on growth and uptake of osmolytes. In strain DP-L1044, which had OpuC and the two glycine betaine porters Gbu and BetL, triethylglycine was most effective in inhibiting growth in the presence of glycine betaine, but trigonelline was best at inhibiting growth in the presence of carnitine. Carnitine uptake through OpuC was inhibited by γ-butyrobetaine. Dimethylglycine inhibited both glycine betaine and carnitine uptake through the Gbu porter. Carnitine uptake through the Gbu porter was inhibited by triethylglycine. Glycine betaine uptake through the BetL porter was strongly inhibited by trigonelline and triethylglycine. These results suggest that it is possible to reduce the growth of L. monocytogenes under osmotically stressful conditions by inhibiting glycine betaine and carnitine uptake but that to do so, multiple uptake systems must be affected. PMID:12406761

  15. Crystal lattice dependency of the free radicals found in irradiated glycine

    NARCIS (Netherlands)

    Bie, M.J.A. de; Braams, R.

    1969-01-01

    The EPR spectra, and hence the stable free radicals, are different for the - or γ-irradiated α-, β- and γ-crystal forms of polycrystalline glycone. Therefore comparisons of the trideutero-glycine EPR spectrum with the EPR spectra of non-deuterated glycine are open to question

  16. Characterization and regulation of glycine transport in Fusarium oxysporum var. lini.

    Science.gov (United States)

    Castro, I M; Lima, A A; Nascimento, A F; Ruas, M M; Nicoli, J R; Brandão, R L

    1996-08-01

    Glycine was transported in Fusarium oxysporum cells, grown on glycine as the sole source of carbon and nitrogen, by a facilitated diffusion transport system with a half-saturation constant (Ks) of 11 mM and a maximum velocity (Vmax) of 1.2 mM (g dry weight)-1 h-1 at pH 5.0 and 26 degrees C. Under conditions of nitrogen starvation, the same system was present together with a high-affinity one (Ks) of about 47 microM and Vmax of about 60 microM (g dry weight)-1 h-1). The low-affinity system was more specific than the high-affinity system. Cells grown on gelatine showed the same behavior. In cells grown on glucose-gelatine medium, the low-affinity system was poorly expressed even after carbon and nitrogen starvation. Moreover, addition of glucose to cells grown on glycine and resuspended in mineral medium caused an increase of the glycine transport probably due to a boost in protein synthesis. This stimulation did not affect the Ks of the low-affinity system. These results demonstrate that, as is the case for other eukaryotic systems, F. oxysporum glycine transport is under control of nitrogen sources but its regulation by carbon sources appears to be more complex.

  17. Eukaryotic beta-alanine synthases are functionally related but have a high degree of structural diversity

    DEFF Research Database (Denmark)

    Gojkovic, Zoran; Sandrini, Michael; Piskur, Jure

    2001-01-01

    no pyrimidine catabolic pathway, it enabled growth on N-carbamyl- beta -alanine as the sole nitrogen source. The D. discoideum and D. melanogaster PYD3 gene products are similar to mammalian beta -alanine synthases. In contrast, the S. kluyveri protein is quite different from these and more similar to bacterial......beta -Alanine synthase (EC 3.5.1.6), which catalyzes the final step of pyrimidine catabolism, has only been characterized in mammals. A Saccharomyces kluyveri pyd3 mutant that is unable to grow on N-carbamy-beta -alanine as the sole nitrogen source and exhibits diminished beta -alanine synthase...... N- carbamyl amidohydrolases. All three beta -alanine synthases are to some degree related to various aspartate transcarbamylases, which catalyze the second step of the de novo pyrimidine biosynthetic pathway. PYD3 expression in yeast seems to be inducible by dihydrouracil and N...

  18. Electron Paramagnetic Resonance signal ratio of Alanine Pellets In Nuclear Power Plants

    International Nuclear Information System (INIS)

    Choi, Hoon; Sung, In Bok; Lee, Byung Il; Lim, Young Ki

    2011-01-01

    As a dosimeter for ESR dosimetry, alanine has many useful features including relatively long endurance time of radicals and almost no difference with the radiation dose rate and radiation quality. Alanine dosimeters have been accepted as transfer dosimeters for their good precision at high radiation range. For alanine/ESR spectra, it was reported that the peaks of the spectra are due to the three kinds of radicals induced by radiation. The ratio of the weak 'satellite line' and the central peak of the three man in alanine specta(in this study x /y ratio ) are changed on the LET value of radiation. In case of lithium formate monohydrate was recently identified as a promising dosimetric material. in addition, it was reported the the peak height in the signal spectra is not easily saturated when power is irradiated with relatively high LET radiation such as neutron rays. The difference in the peak height ratio was reported to be caused by increased local radical density following the radiation of high LET. The spectrum shape of some alanine dosimeter installed in the containment buildings of NPPs showed differences in comparison with dosimeters exposed only to gamma rays. There was apparent change of spectra, expressed as the 'x/y ratio'. As noted in other papers, high LET radiation such as neutron rays causes shape changes of the spectrum of alanine dosimeters. Thus, the unanticipated high dose level and low 'x/y ratio' of some alanine dosimeters from the containment building could be explained b exposure to mixed radiation with high LET. Generally, the locations evaluated in this study are regarded as being exposed only to gamma rays, because the positions are blocked from direct neutron rays, because the positions are blocked from direct neutron rays from reactor by thick cement barriers and heavy instruments.

  19. Branched-chain amino acid supplementation during bed rest: effect on recovery

    Science.gov (United States)

    Stein, T. P.; Donaldson, M. R.; Leskiw, M. J.; Schluter, M. D.; Baggett, D. W.; Boden, G.

    2003-01-01

    Bed rest is associated with a loss of protein from the weight-bearing muscle. The objectives of this study are to determine whether increasing dietary branched-chain amino acids (BCAAs) during bed rest improves the anabolic response after bed rest. The study consisted of a 1-day ambulatory period, 14 days of bed rest, and a 4-day recovery period. During bed rest, dietary intake was supplemented with either 30 mmol/day each of glycine, serine, and alanine (group 1) or with 30 mmol/day each of the three BCAAs (group 2). Whole body protein synthesis was determined with U-(15)N-labeled amino acids, muscle, and selected plasma protein synthesis with l-[(2)H(5)]phenylalanine. Total glucose production and gluconeogenesis from alanine were determined with l-[U-(13)C(3)]alanine and [6,6-(2)H(2)]glucose. During bed rest, nitrogen (N) retention was greater with BCAA feeding (56 +/- 6 vs. 26 +/- 12 mg N. kg(-1). day(-1), P < 0.05). There was no effect of BCAA supplementation on either whole body, muscle, or plasma protein synthesis or the rate of 3-MeH excretion. Muscle tissue free amino acid concentrations were increased during bed rest with BCAA (0.214 +/- 0.066 vs. 0.088 +/- 0.12 nmol/mg protein, P < 0.05). Total glucose production and gluconeogenesis from alanine were unchanged with bed rest but were significantly reduced (P < 0.05) with the BCAA group in the recovery phase. In conclusion, the improved N retention during bed rest is due, at least in part, to accretion of amino acids in the tissue free amino acid pools. The amount accreted is not enough to impact protein kinetics in the recovery phase but does improve N retention by providing additional essential amino acids in the early recovery phase.

  20. Preferential Pathway for Glycine Formation in Star-Forming Regions

    Science.gov (United States)

    Pilling, S.; Boechat-Roberty, H. M.; Baptista, L.; Santos A. C., F.

    Interstellar clouds, similar to that from which the solar system was formed, contain many organic molecules including aldehydes, acids, ketones, and sugars Ehrenfreund & Charnley (2000). Those organic compounds have important functions in terrestrial biochemistry and could also have been important in prebiotic synthesis. The simplest amino acid, glycine (NH2CH2COOH), was recently detected in the hot molecular cores Sgr B2(N-LMH), Orion KL, and W51 e1/e2 Kuan et al. (2003). The formic acid (HCOOH) and acetic acid(CH3COOH) have also been detected in those regions Liu et al. (2002), Remijan et al. (2004). The goal of this work is to study experimentally photoionization and photodissociation processes of glycine precursor molecules, acetic acid and formic acid to elucidate a possible preferentially in the glycine synthesis between ice and gas phase. The measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS), employing soft X-ray photons from a toroidal grating monochromator TGM) beamline (100 - 310 eV). The experimental set up consists of a high vacuum chamber with a Time-Of-Flight Mass Spectrometer (TOF-MS). Mass spectra were obtained using PhotoElectron PhotoIon Coincidence (PEPICO) technique. Kinetic energy distributions and abundances for each ionic fragment have been obtained from the analysis of the corresponding peak shapes in the mass spectra. Dissociative and non-dissociative photoionization cross sections for both molecules were also determined Boechat-Roberty, Pilling & Santos (2005). Due to the high photodissociation cross section of formic acid it is possible that in PDRs regions, just after molecules evaporation from the grains surface, it is almost destructed by soft X-rays, justifying the observed low abundance of HCOOH in gaseous phase Ehrenfreund et al. (2001). Acetic acid have shown to be more stable to the ionizing field, and its main outcomes from dissociation process were the reactive ionic fragments COOH+ and CH3CO+. To

  1. A DFT study of adsorption of glycine onto the surface of BC{sub 2}N nanotube

    Energy Technology Data Exchange (ETDEWEB)

    Soltani, Alireza, E-mail: Alireza.soltani46@yahoo.com [Joints, Bones and Connective Tissue Research Center, Golestan University of Medical Sciences, Gorgan (Iran, Islamic Republic of); Young Researchers and Elite Club, Gorgan Branch, Islamic Azad University, Gorgan (Iran, Islamic Republic of); Azmoodeh, Zivar [Department of Physics, Payame Noor University, P.O. Box 19395-3697, Tehran (Iran, Islamic Republic of); Javan, Masoud Bezi [Physics Department, Faculty of Sciences, Golestan University, Gorgan (Iran, Islamic Republic of); Lemeski, E. Tazikeh [Department of Chemistry, Gorgan Branch, Islamic Azad University, Gorgan (Iran, Islamic Republic of); Karami, Leila [Institute of Biochemistry and Biophysics, University of Tehran, Tehran (Iran, Islamic Republic of)

    2016-10-30

    Highlights: • Glycine adsorption over the pristine BC{sub 2}N nanotubes is investigated by DFT calculations. • Adsorption of glycine in its zwitterionic form is stronger in comparison with the radical form. • Adsorption of glycine from its amine head on adsorbent leads to a significant decrease in the electronic properties. - Abstract: A theoretical study of structure and the energy interaction of amino acid glycine (NH{sub 2}CH{sub 2}COOH) with BC{sub 2}N nanotube is crucial for apperception behavior occurring at the nanobiointerface. Herein, we studied the adsorption of glycine in their radical and zwitterionic forms upon the surface of BC{sub 2}N nanotube using M06 functional and 6-311G** standard basis set. We also considered the different orientations of the glycine amino acid on the surface of adsorbent. Further, we found out that the stability of glycine from its carbonyl group is higher than hydroxyl and amine groups. Our results also indicated that the electronic structure of BC{sub 2}N nanotube on the adsorption of glycine from its amine group is more altered than the other groups. Our study exhibits that opto-electronic property of adsorbent is changed after the glycine adsorption.

  2. The uropathogenic species Staphylococcus saprophyticus tolerates a high concentration of D-serine.

    Science.gov (United States)

    Sakinç, Türkân; Michalski, Nadine; Kleine, Britta; Gatermann, Sören G

    2009-10-01

    Human urine contains a relatively high concentration of d-serine, which is toxic to several nonuropathogenic bacteria, but can be utilized or detoxified by uropathogenic Escherichia coli (UPEC). The sequenced genome of uropathogenic Staphylococcus saprophyticus contains a gene with homology to the d-serine deaminase gene (dsdA) of UPEC. We found the gene in several clinical isolates of S. saprophyticus; however, the gene was absent in Staphylococcus xylosus and Staphylococcus cohnii, phylogenetically close relatives of S. saprophyticus, and could also not be detected in isolates of Staphylococcus aureus, Staphylococcus epidermidis and 13 other staphylococcal species. In addition, the genomes of other sequenced staphylococci do not harbor homologues of this operon. Interestingly, S. saprophyticus could grow in media supplemented with relatively high concentrations of d-serine, whereas S. aureus, S. epidermidis and other staphylococcal species could not. The association of the dsdA gene with growth in media including d-serine was proved by introducing the gene into S. aureus Newman. Given the fact that UPEC and S. saprophyticus tolerate this compound, d-serine utilization and detoxification may be a general property of uropathogenic bacteria. © 2009 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  3. An efficient protocol for the complete incorporation of methyl-protonated alanine in perdeuterated protein

    International Nuclear Information System (INIS)

    Ayala, Isabel; Sounier, Remy; Use, Nathalie; Gans, Pierre; Boisbouvier, Jerome

    2009-01-01

    A strategy for the introduction of ( 1 H, 13 C-methyl)-alanine into perdeuterated proteins is described. Specific protonation of alanine methyl groups to a level of 95% can be achieved by overexpressing proteins in M9/D 2 O based bacterial growth medium supplemented with 800 mg/l of 2-[ 2 H], 3-[ 13 C] l-alanine. However, though simple, this approach results in undesired, non-specific background labeling due to isotope scrambling via different amino acid metabolic pathways. Following a careful analysis of known metabolic pathways we found that co-addition of perdeuterated forms of α-ketoisovalerate-d 7 , succinate-d 4 and l-isoleucine-d 10 with labeled l-alanine, reduces undesired background labeling to <1%. When combined with recently developed methyl TROSY experiments, this methyl-specific labeling protocol permits the acquisition of excellent quality correlation spectra of alanine methyl groups in high molecular weight proteins. Our cost effective strategy offers a significant enhancement in the level of incorporation of methyl-labeled alanine in overexpressed proteins over previously reported methods

  4. Insights into the evolution of enzyme substrate promiscuity after the discovery of (βα)₈ isomerase evolutionary intermediates from a diverse metagenome.

    Science.gov (United States)

    Noda-García, Lianet; Juárez-Vázquez, Ana L; Ávila-Arcos, María C; Verduzco-Castro, Ernesto A; Montero-Morán, Gabriela; Gaytán, Paul; Carrillo-Tripp, Mauricio; Barona-Gómez, Francisco

    2015-06-10

    Current sequence-based approaches to identify enzyme functional shifts, such as enzyme promiscuity, have proven to be highly dependent on a priori functional knowledge, hampering our ability to reconstruct evolutionary history behind these mechanisms. Hidden Markov Model (HMM) profiles, broadly used to classify enzyme families, can be useful to distinguish between closely related enzyme families with different specificities. The (βα)8-isomerase HisA/PriA enzyme family, involved in L-histidine (HisA, mono-substrate) biosynthesis in most bacteria and plants, but also in L-tryptophan (HisA/TrpF or PriA, dual-substrate) biosynthesis in most Actinobacteria, has been used as model system to explore evolutionary hypotheses and therefore has a considerable amount of evolutionary, functional and structural knowledge available. We searched for functional evolutionary intermediates between the HisA and PriA enzyme families in order to understand the functional divergence between these families. We constructed a HMM profile that correctly classifies sequences of unknown function into the HisA and PriA enzyme sub-families. Using this HMM profile, we mined a large metagenome to identify plausible evolutionary intermediate sequences between HisA and PriA. These sequences were used to perform phylogenetic reconstructions and to identify functionally conserved amino acids. Biochemical characterization of one selected enzyme (CAM1) with a mutation within the functionally essential N-terminus phosphate-binding site, namely, an alanine instead of a glycine in HisA or a serine in PriA, showed that this evolutionary intermediate has dual-substrate specificity. Moreover, site-directed mutagenesis of this alanine residue, either backwards into a glycine or forward into a serine, revealed the robustness of this enzyme. None of these mutations, presumably upon functionally essential amino acids, significantly abolished its enzyme activities. A truncated version of this enzyme (CAM2

  5. Polymerization of alanine in the presence of a non-swelling montmorillonite

    Science.gov (United States)

    Paecht-Horowitz, M.; Lahav, N.

    1977-01-01

    Alanine, starting from alanine-adenylate, has been polymerized in the presence of non-swelling Al-montmorillonite. The yield of polymerization is much lower than that obtained in the presence of swelling Na-montmorillonite. The possibility that the changing interlayer spacing in Na-montmorillonite might be responsible for its catalytic properties, is discussed.

  6. A thin alanine-polyethylene film dosimetry system with diffuse reflection spectrophotometric evaluation

    International Nuclear Information System (INIS)

    Zagorski, Z.P.; Rafalski, A.

    1995-01-01

    Characteristics of a new alanine dosimeter in the shape of a thin film, with the measurement of optical absorption of the CH 3 CHCOO - radical is described. That type of dosimeter, ALA/DRS (for diffuse reflection spectrophotometry) is compared, to an alanine dosimeter with EPR evaluation (ALA/EPR for short). In many respects the simple ALA/DRS version, as the alanine-polyethylene composite is superior. The paper shows the importance of the new experimental approach to free radical research in solid state radiation chemistry. (author). 7 refs., 3 figs

  7. Effects of glycine on motor performance in rats after traumatic spinal cord injury.

    Science.gov (United States)

    Gonzalez-Piña, Rigoberto; Nuño-Licona, Alberto

    2007-01-01

    It has been reported that glycine improves some functions lost after spinal cord injury (SCI). In order to assess the effects of glycine administration on motor performance after SCI, we used fifteen male Wistar rats distributed into three groups: sham (n = 3), spinal-cord injury (n = 6,) and spinal cord injury + glycine (n = 6). Motor performance was assessed using the beam-walking paradigm and footprint analysis. Results showed that for all animals with spinal-cord injury, scores in the beam-walking increased, which is an indication of increased motor deficit. In addition, footprint analysis showed a decrease in stride length and an increase in stride angle, additional indicators of motor deficit. These effects trended towards recovery after 8 weeks of recording and trended toward improvement by glycine administration; the effect was not significant. These results suggest that glycine replacement alone is not sufficient to improve the motor deficits that occur after SCI.

  8. Activation of synaptic and extrasynaptic glycine receptors by taurine in preoptic hypothalamic neurons.

    Science.gov (United States)

    Bhattarai, Janardhan Prasad; Park, Soo Joung; Chun, Sang Woo; Cho, Dong Hyu; Han, Seong Kyu

    2015-11-03

    Taurine is an essential amino-sulfonic acid having a fundamental function in the brain, participating in both cell volume regulation and neurotransmission. Using a whole cell voltage patch clamp technique, the taurine-activated neurotransmitter receptors in the preoptic hypothalamic area (PHA) neurons were investigated. In the first set of experiments, different concentrations of taurine were applied on PHA neurons. Taurine-induced responses were concentration-dependent. Taurine-induced currents were action potential-independent and sensitive to strychnine, suggesting the involvement of glycine receptors. In addition, taurine activated not only α-homomeric, but also αβ-heteromeric glycine receptors in PHA neurons. Interestingly, a low concentration of taurine (0.5mM) activated glycine receptors, whereas a higher concentration (3mM) activated both glycine and gamma-aminobutyric acid A (GABAA) receptors in PHA neurons. These results suggest that PHA neurons are influenced by taurine and respond via glycine and GABAA receptors. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. [Dynamics of the amino acid composition of the medium during cultivation of isolated organs by the directed perfusion method].

    Science.gov (United States)

    Barashkov, V A; Gitel'zon, I I; Nefedov, V P; Trubachev, I N

    1975-07-01

    The dynamics of the amino acid composition of the medium under conditions of adequate perfusion of the isolated organs of a dog (sternum, kidney and liver) was studied. It was found that after a 6-hour perfusion of the complex of organs the amount in the perfusion medium of such amino acids as histidine, lysine, alanine, considerably increased, whereas the amount of arginine, serine, aspartic acid, threonine with glutamine, isoleucine, proline, leucine and valine decreased as compared with their initial concentration. The dynamics of the amino acid medium composition during a 4-hour perfusion was studied in experiments with the isolated sternum. The concentration of alanine, lysine and histidine increased in the medium. At the same time there was seen a decrease in the concentration of serine, aspartic acid, isoleucine, tyrosine and phenyl-alanine.

  10. Degradation of pyrimidines in Saccharomyces kluyveri: transamination of beta-alanine

    DEFF Research Database (Denmark)

    Schnackerz, K D; Andersen, G; Dobritzsch, D

    2008-01-01

    Beta-alanine is an intermediate in the reductive degradation of uracil. Recently we have identified and characterized the Saccharomyces kluyveri PYD4 gene and the corresponding enzyme beta -alanine aminotransferase ((Sk)Pyd4p), highly homologous to eukaryotic gamma-aminobutyrate aminotransferase ...

  11. Improvement in regional CBF by L-serine contributes to its neuroprotective effect in rats after focal cerebral ischemia.

    Directory of Open Access Journals (Sweden)

    Tao-Jie Ren

    Full Text Available To investigate the mechanisms underlying the neuroprotective effect of L-serine, permanent focal cerebral ischemia was induced by occlusion of the middle cerebral artery while monitoring cerebral blood flow (CBF. Rats were divided into control and L-serine-treated groups after middle cerebral artery occlusion. The neurological deficit score and brain infarct volume were assessed. Nissl staining was used to quantify the cortical injury. L-serine and D-serine levels in the ischemic cortex were analyzed with high performance liquid chromatography. We found that L-serine treatment: 1 reduced the neurological deficit score, infarct volume and cortical neuron loss in a dose-dependent manner; 2 improved CBF in the cortex, and this effect was inhibited in the presence of apamin plus charybdotoxin while the alleviation of both neurological deficit score and infarct volume was blocked; and 3 increased the amount of L-serine and D-serine in the cortex, and inhibition of the conversion of L-serine into D-serine by aminooxyacetic acid did not affect the reduction of neurological deficit score and infarct volume by L-serine. In conclusion, improvement in regional CBF by L-serine may contribute to its neuroprotective effect on the ischemic brain, potentially through vasodilation which is mediated by the small- and intermediate-conductance Ca(2+-activated K(+ channels on the cerebral blood vessel endothelium.

  12. Relative response of the alanine dosimeter to medium energy x-rays.

    Science.gov (United States)

    Anton, M; Büermann, L

    2015-08-07

    The response of the alanine dosimeter to kilovoltage x-rays with respect to the dose to water was measured, relative to the response to Co-60 radiation.Two series of x-ray qualities were investigated, one ranging from 30 kV to 100 kV tube voltage (TW series), the other one ranging from 70 kV to 280 kV (TH series). Due to the use of the water calorimeter as a primary standard, the uncertainty of the delivered dose is significantly lower than for other published data. The alanine response was measured as described in a previous publication (Anton et al 2013 Phys. Med. Biol. 58 3259-82). The uncertainty component due to the alanine measurement and analysis is ⩽0.4%, the major part of the combined uncertainty of the relative response originates from the uncertainty of the delivered dose. The relative uncertainties of the relative response vary from ⩽2% for the TW series to ⩽1.1% for the TH series.Different from the behaviour of the alanine dosimeter for megavoltage x-rays or electrons, the relative response drops significantly from unity for Co-60 radiation to less than 64% for the TW quality with a tube voltage of 30 kV. In order to reproduce this behaviour through Monte Carlo simulations, not only the ratio of the absorbed dose to alanine to the absorbed dose to water has to be known, but also the intrinsic efficiency, i.e. the dependence of the number of free radicals generated per unit of absorbed dose on the photon energy. This quantity is not yet accessible for the TW series.For a possible use of the alanine dosimeter for kilovoltage x-rays, for example in electronic brachytherapy, users should rely on the measured data for the relative response which have become available with this publication.

  13. End-to-end tests using alanine dosimetry in scanned proton beams

    Science.gov (United States)

    Carlino, A.; Gouldstone, C.; Kragl, G.; Traneus, E.; Marrale, M.; Vatnitsky, S.; Stock, M.; Palmans, H.

    2018-03-01

    This paper describes end-to-end test procedures as the last fundamental step of medical commissioning before starting clinical operation of the MedAustron synchrotron-based pencil beam scanning (PBS) therapy facility with protons. One in-house homogeneous phantom and two anthropomorphic heterogeneous (head and pelvis) phantoms were used for end-to-end tests at MedAustron. The phantoms were equipped with alanine detectors, radiochromic films and ionization chambers. The correction for the ‘quenching’ effect of alanine pellets was implemented in the Monte Carlo platform of the evaluation version of RayStation TPS. During the end-to-end tests, the phantoms were transferred through the workflow like real patients to simulate the entire clinical workflow: immobilization, imaging, treatment planning and dose delivery. Different clinical scenarios of increasing complexity were simulated: delivery of a single beam, two oblique beams without and with range shifter. In addition to the dose comparison in the plastic phantoms the dose obtained from alanine pellet readings was compared with the dose determined with the Farmer ionization chamber in water. A consistent systematic deviation of about 2% was found between alanine dosimetry and the ionization chamber dosimetry in water and plastic materials. Acceptable agreement of planned and delivered doses was observed together with consistent and reproducible results of the end-to-end testing performed with different dosimetric techniques (alanine detectors, ionization chambers and EBT3 radiochromic films). The results confirmed the adequate implementation and integration of the new PBS technology at MedAustron. This work demonstrates that alanine pellets are suitable detectors for end-to-end tests in proton beam therapy and the developed procedures with customized anthropomorphic phantoms can be used to support implementation of PBS technology in clinical practice.

  14. Glycine receptor: light microscopic autoradiographic localization with [3H]strychnine

    International Nuclear Information System (INIS)

    Zarbin, M.A.; Wamsley, J.K.; Kuhar, M.J.

    1981-01-01

    Glycine receptors have been localized by autoradiography in the rat central nervous system (CNS) using [ 3 H]strychnine. The gross distribution of receptors is in excellent accord with the distribution determined by filtration binding assays. Specifically, the density of glycine receptors is greatest in the gray matter of the spinal cord and decreases progressively in regions more rostral in the neuraxis. Glycine receptors were found to be associated with both sensory and motor systems in the CNS. Moreover, there is a striking correlation between areas of high strychnine binding site density and areas in which glycine has been found to be electrophysiologically active. Finally, the anatomic localization of strychnine binding sites may help explain many of the signs and symptoms of strychnine ingestion. For example, individuals consuming subconvulsive doses of strychnine frequently experience altered cutaneous and auditory sensation. We have localized strychnine receptors in areas of the acoustic system known to influence discriminative aspects of audition and in areas of the spinal cord and trigeminal nuclei which modulate discriminative aspects of cutaneous sensation. The alteration of visceral functions (e.g., blood pressure and respiratory rate) associated with strychnine ingestion may be accounted for in a similar manner

  15. Affinity of hydroxyapatite for furfural and a brown pigment formed by furfural and glycine.

    Science.gov (United States)

    Nordbö, H; Eriksen, H M; Rölla, G

    1979-10-01

    The affinity of hydroxyapatite for furfural and a brown pigment formed by furfural and glycine was studied. A series of mixtures containing 1 M furfural and 0.25-2.0 M glycine were incubated at 37 degrees C and aliquots of hydroxyapatite added. The apatite showed a strong affinity for the brown pigment formed, and an excess of glycine in the mixtures appeared to enhance the binding. The adsorption of furfural to hydroxyapatite was estimated by a spectrophotometric method. The data revealed that pretreatment with CaCl2 and glycine significantly increased the adsorption of furfural.

  16. Chk1 protects against chromatin bridges by constitutively phosphorylating BLM serine 502 to inhibit BLM degradation.

    Science.gov (United States)

    Petsalaki, Eleni; Dandoulaki, Maria; Morrice, Nick; Zachos, George

    2014-09-15

    Chromatin bridges represent incompletely segregated chromosomal DNA connecting the anaphase poles and can result in chromosome breakage. The Bloom's syndrome protein helicase (BLM, also known as BLMH) suppresses formation of chromatin bridges. Here, we show that cells deficient in checkpoint kinase 1 (Chk1, also known as CHEK1) exhibit higher frequency of chromatin bridges and reduced BLM protein levels compared to controls. Chk1 inhibition leads to BLM ubiquitylation and proteasomal degradation during interphase. Furthermore, Chk1 constitutively phosphorylates human BLM at serine 502 (S502) and phosphorylated BLM localises to chromatin bridges. Mutation of S502 to a non-phosphorylatable alanine residue (BLM-S502A) reduces the stability of BLM, whereas expression of a phospho-mimicking BLM-S502D, in which S502 is mutated to aspartic acid, stabilises BLM and prevents chromatin bridges in Chk1-deficient cells. In addition, wild-type but not BLM-S502D associates with cullin 3, and cullin 3 depletion rescues BLM accumulation and localisation to chromatin bridges after Chk1 inhibition. We propose that Chk1 phosphorylates BLM-S502 to inhibit cullin-3-mediated BLM degradation during interphase. These results suggest that Chk1 prevents deleterious anaphase bridges by stabilising BLM. © 2014. Published by The Company of Biologists Ltd.

  17. 4-Chloropropofol enhances chloride currents in human hyperekplexic and artificial mutated glycine receptors

    Directory of Open Access Journals (Sweden)

    de la Roche Jeanne

    2012-09-01

    Full Text Available Abstract Background The mammalian neurological disorder hereditary hyperekplexia can be attributed to various mutations of strychnine sensitive glycine receptors. The clinical symptoms of “startle disease” predominantly occur in the newborn leading to convulsive hypertonia and an exaggerated startle response to unexpected mild stimuli. Amongst others, point mutations R271Q and R271L in the α1-subunit of strychnine sensitive glycine receptors show reduced glycine sensitivity and cause the clinical symptoms of hyperekplexia. Halogenation has been shown to be a crucial structural determinant for the potency of a phenolic compound to positively modulate glycine receptor function. The aim of this in vitro study was to characterize the effects of 4-chloropropofol (4-chloro-2,6-dimethylphenol at four glycine receptor mutations. Methods Glycine receptor subunits were expressed in HEK 293 cells and experiments were performed using the whole-cell patch-clamp technique. Results 4-chloropropofol exerted a positive allosteric modulatory effect in a low sub-nanomolar concentration range at the wild type receptor (EC50 value of 0.08 ± 0.02 nM and in a micromolar concentration range at the mutations (1.3 ± 0.6 μM, 0.1 ± 0.2 μM, 6.0 ± 2.3 μM and 55 ± 28 μM for R271Q, L, K and S267I, respectively. Conclusions 4-chloropropofol might be an effective compound for the activation of mutated glycine receptors in experimental models of startle disease.

  18. Kazal-type serine proteinase inhibitors in the midgut of Phlebotomus papatasi

    Directory of Open Access Journals (Sweden)

    Leah Theresa Sigle

    2013-09-01

    Full Text Available Sandflies (Diptera: Psychodidae are important disease vectors of parasites of the genus Leishmania, as well as bacteria and viruses. Following studies of the midgut transcriptome of Phlebotomus papatasi, the principal vector of Leishmania major, two non-classical Kazal-type serine proteinase inhibitors were identified (PpKzl1 and PpKzl2. Analyses of expression profiles indicated that PpKzl1 and PpKzl2 transcripts are both regulated by blood-feeding in the midgut of P. papatasi and are also expressed in males, larva and pupa. We expressed a recombinant PpKzl2 in a mammalian expression system (CHO-S free style cells that was applied to in vitro studies to assess serine proteinase inhibition. Recombinant PpKzl2 inhibited α-chymotrypsin to 9.4% residual activity and also inhibited α-thrombin and trypsin to 33.5% and 63.9% residual activity, suggesting that native PpKzl2 is an active serine proteinase inhibitor and likely involved in regulating digestive enzymes in the midgut. Early stages of Leishmania are susceptible to killing by digestive proteinases in the sandfly midgut. Thus, characterising serine proteinase inhibitors may provide new targets and strategies to prevent transmission of Leishmania.

  19. Phosphorylation of serine 248 of C/EBPα is dispensable for myelopoiesis but its disruption leads to a low penetrant myeloid disorder with long latency.

    Directory of Open Access Journals (Sweden)

    Marie S Hasemann

    Full Text Available BACKGROUND: Transcription factors play a key role in lineage commitment and differentiation of stem cells into distinct mature cells. In hematopoiesis, they regulate lineage-specific gene expression in a stage-specific manner through various physical and functional interactions with regulatory proteins that are simultanously recruited and activated to ensure timely gene expression. The transcription factor CCAAT/enhancer binding protein α (C/EBPα is such a factor and is essential for the development of granulocytic/monocytic cells. The activity of C/EBPα is regulated on several levels including gene expression, alternative translation, protein interactions and posttranslational modifications, such as phosphorylation. In particular, the phosphorylation of serine 248 of the transactivation domain has been shown to be of crucial importance for granulocytic differentiation of 32Dcl3 cells in vitro. METHODOLOGY/PRINCIPAL FINDINGS: Here, we use mouse genetics to investigate the significance of C/EBPα serine 248 in vivo through the construction and analysis of Cebpa(S248A/S248A knock-in mice. Surprisingly, 8-week old Cebpa(S248A/S248A mice display normal steady-state hematopoiesis including unaltered development of mature myeloid cells. However, over time some of the animals develop a hematopoietic disorder with accumulation of multipotent, megakaryocytic and erythroid progenitor cells and a mild impairment of differentiation along the granulocytic-monocytic lineage. Furthermore, BM cells from Cebpa(S248A/S248A animals display a competitive advantage compared to wild type cells in a transplantation assay. CONCLUSIONS/SIGNIFICANCE: Taken together, our data shows that the substitution of C/EBPα serine 248 to alanine favors the selection of the megakaryocytic/erythroid lineage over the monocytic/granulocytic compartment in old mice and suggests that S248 phosphorylation may be required to maintain proper hematopoietic homeostasis in response to

  20. Phosphorylation of serine 248 of C/EBPα is dispensable for myelopoiesis but its disruption leads to a low penetrant myeloid disorder with long latency.

    Science.gov (United States)

    Hasemann, Marie S; Schuster, Mikkel B; Frank, Anne-Katrine; Theilgaard-Mönch, Kim; Pedersen, Thomas Å; Nerlov, Claus; Porse, Bo T

    2012-01-01

    Transcription factors play a key role in lineage commitment and differentiation of stem cells into distinct mature cells. In hematopoiesis, they regulate lineage-specific gene expression in a stage-specific manner through various physical and functional interactions with regulatory proteins that are simultanously recruited and activated to ensure timely gene expression. The transcription factor CCAAT/enhancer binding protein α (C/EBPα) is such a factor and is essential for the development of granulocytic/monocytic cells. The activity of C/EBPα is regulated on several levels including gene expression, alternative translation, protein interactions and posttranslational modifications, such as phosphorylation. In particular, the phosphorylation of serine 248 of the transactivation domain has been shown to be of crucial importance for granulocytic differentiation of 32Dcl3 cells in vitro. Here, we use mouse genetics to investigate the significance of C/EBPα serine 248 in vivo through the construction and analysis of Cebpa(S248A/S248A) knock-in mice. Surprisingly, 8-week old Cebpa(S248A/S248A) mice display normal steady-state hematopoiesis including unaltered development of mature myeloid cells. However, over time some of the animals develop a hematopoietic disorder with accumulation of multipotent, megakaryocytic and erythroid progenitor cells and a mild impairment of differentiation along the granulocytic-monocytic lineage. Furthermore, BM cells from Cebpa(S248A/S248A) animals display a competitive advantage compared to wild type cells in a transplantation assay. Taken together, our data shows that the substitution of C/EBPα serine 248 to alanine favors the selection of the megakaryocytic/erythroid lineage over the monocytic/granulocytic compartment in old mice and suggests that S248 phosphorylation may be required to maintain proper hematopoietic homeostasis in response to changes in the wiring of cellular signalling networks. More broadly, the marked differences

  1. Investigations on the nucleation kinetics of γ-glycine single crystal

    International Nuclear Information System (INIS)

    Yogambal, C.; Rajan Babu, D.; Ezhil Vizhi, R.

    2014-01-01

    Single crystals of γ-glycine were grown by slow evaporation technique. The crystalline system was confirmed by single crystal X-ray diffraction analysis. The optical absorption study has shown that the grown crystal possesses lower cut-off wavelength. Solubility and metastable zone width were estimated for different temperatures. The induction period of title compound was determined by varying the temperature and concentration. Nucleation parameters such as Gibbs volume free energy change (ΔG v ), interfacial tension (γ), critical free energy change of the nucleus (ΔG ⁎ ), nucleation rate (J), number of molecules in the critical nucleus (i ⁎ ) have been calculated for the aqueous solution grown γ-glycine single crystals. The second harmonic generation (SHG) of γ-glycine was confirmed by Q-switched Nd:YAG laser technique

  2. Carnosine and anserine homeostasis in skeletal muscle and heart is controlled by β‐alanine transamination

    Science.gov (United States)

    Blancquaert, Laura; Baba, Shahid P.; Kwiatkowski, Sebastian; Stautemas, Jan; Stegen, Sanne; Barbaresi, Silvia; Chung, Weiliang; Boakye, Adjoa A.; Hoetker, J. David; Bhatnagar, Aruni; Delanghe, Joris; Vanheel, Bert; Veiga‐da‐Cunha, Maria; Derave, Wim

    2016-01-01

    Key points Using recombinant DNA technology, the present study provides the first strong and direct evidence indicating that β‐alanine is an efficient substrate for the mammalian transaminating enzymes 4‐aminobutyrate‐2‐oxoglutarate transaminase and alanine‐glyoxylate transaminase.The concentration of carnosine and anserine in murine skeletal and heart muscle depends on circulating availability of β‐alanine, which is in turn controlled by degradation of β‐alanine in liver and kidney.Chronic oral β‐alanine supplementation is a popular ergogenic strategy in sports because it can increase the intracellular carnosine concentration and subsequently improve the performance of high‐intensity exercises. The present study can partly explain why the β‐alanine supplementation protocol is so inefficient, by demonstrating that exogenous β‐alanine can be effectively routed toward oxidation. Abstract The metabolic fate of orally ingested β‐alanine is largely unknown. Chronic β‐alanine supplementation is becoming increasingly popular for improving high‐intensity exercise performance because it is the rate‐limiting precursor of the dipeptide carnosine (β‐alanyl‐l‐histidine) in muscle. However, only a small fraction (3–6%) of the ingested β‐alanine is used for carnosine synthesis. Thus, the present study aimed to investigate the putative contribution of two β‐alanine transamination enzymes, namely 4‐aminobutyrate‐2‐oxoglutarate transaminase (GABA‐T) and alanine‐glyoxylate transaminase (AGXT2), to the homeostasis of carnosine and its methylated analogue anserine. We found that, when transfected into HEK293T cells, recombinant mouse and human GABA‐T and AGXT2 are able to transaminate β‐alanine efficiently. The reaction catalysed by GABA‐T is inhibited by vigabatrin, whereas both GABA‐T and AGXT2 activity is inhibited by aminooxyacetic acid (AOA). Both GABA‐T and AGXT2 are highly expressed in the mouse liver and

  3. Physiological hypercortisolemia increases proteolysis, glutamine, and alanine production

    International Nuclear Information System (INIS)

    Darmaun, D.; Matthews, D.E.; Bier, D.M.

    1988-01-01

    Physiological elevations of plasma cortisol levels, as are encountered in stress and severe trauma, were produced in six normal subjects by infusing them with hydrocortisone for 64 h. Amino acid kinetics were measured in the postabsorptive state using three 4-h infusions of L-[1- 13 C]leucine, L-phenyl[ 2 H 5 ]phenylalanine, L-[2- 15 N]glutamine, and L-[1- 13 C]alanine tracers (1) before, (2) at 12 h, and (3) at 60 h of cortisol infusion. Before and throughout the study, the subjects ate a normal diet of adequate protein and energy intake. The cortisol infusion raised plasma cortisol levels significantly from 10 ± 1 to 32 ± 4 μg/dl, leucine flux from 83 ± 3 to 97 ± 3 μmol·kg -1 ·h -1 , and phenylalanine flux from 34 ± 1 to 39 ± 1 (SE) μmol·kg -1 ·h -1 after 12 h of cortisol infusion. These increases were maintained until the cortisol infusion was terminated. These nearly identical 15% increases in two different essential amino acid appearance rates are reflective of increased whole body protein breakdown. Glutamine flux rose by 12 h of cortisol infusion and remained elevated at the same level at 64 h. The increase in flux was primarily due to a 55% increase in glutamine de novo synthesis. Alanine flux increased with acute hypercortisolemia and increased further at 60 h of cortisol infusion, a result primarily of increased alanine de novo synthesis. Insulin, alanine, and lactate plasma levels responded similarly with significant rises between the acute and chronic periods of cortisol infusion. Thus hypercortisolemia increases both protein breakdown and the turnover of important nonessential amino acids for periods of up to 64 h

  4. Removal of brownish-black tarnish on silver–copper alloy objects with sodium glycinate

    Energy Technology Data Exchange (ETDEWEB)

    Cura D’Ars de Figueiredo, João, E-mail: joaoc@ufmg.br; Asevedo, Samara Santos, E-mail: samaranix@hotmail.com; Barbosa, João Henrique Ribeiro, E-mail: joaohrb@yahoo.com.br

    2014-10-30

    Highlights: • The use of glycinate to remove brownish-black tarnish on silver–copper alloy objects is studied. • The method is easy to use and harmless. It is based in the coordination of Ag and Cu in tarnish with glycinate. • The surface of corroded silver objects and products of reaction were studied and glycinate showed to be very selective for Ag(I) and Cu(II). The selectivity for Ag(I) was studied by means of quantum chemical calculations. - Abstract: This article has the principal aim of presenting a new method of chemical cleaning of tarnished silver–copper alloy objects. The chemical cleaning must be harmless to the health, selective to tarnish removal, and easy to use. Sodium glycinate was selected for the study. The reactions of sodium glycinate with tarnish and the silver–copper alloy were evaluated. Products of the reaction, the lixiviated material, and the esthetics of silver–copper alloy coins (used as prototypes) were studied to evaluate if the proposed method can be applied to the cleaning of silver objects. Silver–copper alloys can be deteriorated through a uniform and superficial corrosion process that produces brownish-black tarnish. This tarnish alters the esthetic of the object. The cleaning of artistic and archeological objects requires more caution than regular cleaning, and it must take into account the procedures for the conservation and restoration of cultural heritage. There are different methods for cleaning silver–copper alloy objects, chemical cleaning is one of them. We studied two chemical cleaning methods that use sodium glycinate and sodium acetylglycinate solutions. Silver–copper alloy coins were artificially corroded in a basic thiourea solution and immersed in solutions of sodium glycinate and sodium acetylglycinate. After immersion, optical microscopy and scanning electron microscopy of the surfaces were studied. The sodium glycinate solution was shown to be very efficient in removing the brownish

  5. Removal of brownish-black tarnish on silver–copper alloy objects with sodium glycinate

    International Nuclear Information System (INIS)

    Cura D’Ars de Figueiredo, João; Asevedo, Samara Santos; Barbosa, João Henrique Ribeiro

    2014-01-01

    Highlights: • The use of glycinate to remove brownish-black tarnish on silver–copper alloy objects is studied. • The method is easy to use and harmless. It is based in the coordination of Ag and Cu in tarnish with glycinate. • The surface of corroded silver objects and products of reaction were studied and glycinate showed to be very selective for Ag(I) and Cu(II). The selectivity for Ag(I) was studied by means of quantum chemical calculations. - Abstract: This article has the principal aim of presenting a new method of chemical cleaning of tarnished silver–copper alloy objects. The chemical cleaning must be harmless to the health, selective to tarnish removal, and easy to use. Sodium glycinate was selected for the study. The reactions of sodium glycinate with tarnish and the silver–copper alloy were evaluated. Products of the reaction, the lixiviated material, and the esthetics of silver–copper alloy coins (used as prototypes) were studied to evaluate if the proposed method can be applied to the cleaning of silver objects. Silver–copper alloys can be deteriorated through a uniform and superficial corrosion process that produces brownish-black tarnish. This tarnish alters the esthetic of the object. The cleaning of artistic and archeological objects requires more caution than regular cleaning, and it must take into account the procedures for the conservation and restoration of cultural heritage. There are different methods for cleaning silver–copper alloy objects, chemical cleaning is one of them. We studied two chemical cleaning methods that use sodium glycinate and sodium acetylglycinate solutions. Silver–copper alloy coins were artificially corroded in a basic thiourea solution and immersed in solutions of sodium glycinate and sodium acetylglycinate. After immersion, optical microscopy and scanning electron microscopy of the surfaces were studied. The sodium glycinate solution was shown to be very efficient in removing the brownish

  6. Integration of ARTP mutagenesis with biosensor-mediated high-throughput screening to improve L-serine yield in Corynebacterium glutamicum.

    Science.gov (United States)

    Zhang, Xin; Zhang, Xiaomei; Xu, Guoqiang; Zhang, Xiaojuan; Shi, Jinsong; Xu, Zhenghong

    2018-05-03

    L-Serine is widely used in the pharmaceutical, food, and cosmetics industries. Although direct fermentative production of L-serine from sugar in Corynebacterium glutamicum has been achieved, the L-serine yield remains relatively low. In this study, atmospheric and room temperature plasma (ARTP) mutagenesis was used to improve the L-serine yield based on engineered C. glutamicum ΔSSAAI strain. Subsequently, we developed a novel high-throughput screening method using a biosensor constructed based on NCgl0581, a transcriptional factor specifically responsive to L-serine, so that L-serine concentration within single cell of C. glutamicum can be monitored via fluorescence-activated cell sorting (FACS). Novel L-serine-producing mutants were isolated from a large library of mutagenized cells. The mutant strain A36-pDser was screened from 1.2 × 10 5 cells, and the magnesium ion concentration in the medium was optimized specifically for this mutant. C. glutamicum A36-pDser accumulated 34.78 g/L L-serine with a yield of 0.35 g/g sucrose, which were 35.9 and 66.7% higher than those of the parent C. glutamicum ΔSSAAI-pDser strain, respectively. The L-serine yield achieved in this mutant was the highest of all reported L-serine-producing strains of C. glutamicum. Moreover, the whole-genome sequencing identified 11 non-synonymous mutations of genes associated with metabolic and transport pathways, which might be responsible for the higher L-serine production and better cell growth in C. glutamicum A36-pDser. This study explored an effective mutagenesis strategy and reported a novel high-throughput screening method for the development of L-serine-producing strains.

  7. Glycine regulates the production of pro-inflammatory cytokines in lean and monosodium glutamate-obese mice.

    Science.gov (United States)

    Alarcon-Aguilar, F J; Almanza-Perez, Julio; Blancas, Gerardo; Angeles, Selene; Garcia-Macedo, Rebeca; Roman, Ruben; Cruz, Miguel

    2008-12-03

    Fat tissue plays an important role in the regulation of inflammatory processes. Increased visceral fat has been associated with a higher production of cytokines that triggers a low-grade inflammatory response, which eventually may contribute to the development of insulin resistance. In the present study, we investigated whether glycine, an amino acid that represses the expression in vitro of pro-inflammatory cytokines in Kupffer and 3T3-L1 cells, can affect in vivo cytokine production in lean and monosodium glutamate-induced obese mice (MSG/Ob mice). Our data demonstrate that glycine treatment in lean mice suppressed TNF-alpha transcriptional expression in fat tissue, and serum protein levels of IL-6 were suppressed, while adiponectin levels were increased. In MSG/Ob mice, glycine suppressed TNF-alpha and IL-6 gene expression in fat tissue and significantly reduced protein levels of IL-6, resistin and leptin. To determine the role of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) in the modulation of this inflammatory response evoked by glycine, we examined its expression levels in fat tissue. Glycine clearly increased PPAR-gamma expression in lean mice but not in MSG/Ob mice. Finally, to identify alterations in glucose metabolism by glycine, we also examined insulin levels and other biochemical parameters during an oral glucose tolerance test. Glycine significantly reduced glucose tolerance and raised insulin levels in lean but not in obese mice. In conclusion, our findings suggest that glycine suppresses the pro-inflammatory cytokines production and increases adiponectin secretion in vivo through the activation of PPAR-gamma. Glycine might prevent insulin resistance and associated inflammatory diseases.

  8. Synthesis of Dipeptide Benzoylalanylglycine Methyl Ester and Corrosion Inhibitor Evaluation by Tafel Equation

    International Nuclear Information System (INIS)

    Abdurrahman, J.; Wahyuningrum, D.; Achmad, S.; Bundjali, B.

    2011-01-01

    Corrosion is one of the major problems in petroleum mining and processing industry. The pipelines used to transport crude oil from reservoir to the processing installation were made from carbon steel that is susceptible towards corrosion. One of the best methods to prevent corrosion that occurred at the inner parts of carbon steel pipelines is to use organic corrosion inhibitor. One of the potent organic corrosion inhibitors is amino acids derivatives. In this study, dipeptide compound namely benzoylalanylglycine methyl ester and benzoylalanylglycine have been synthesized. The structure elucidation of the products was performed by IR, MS and NMR spectroscopy. The determination of corrosion inhibition activity utilized the Tafel method. The corrosion inhibition efficiency of glycine methyl ester, benzoyl alanine, dipeptide benzoylalanylglycine methyl ester and dipeptide benzoylalanylglycine were 63.34 %, 35.86 %, 68.40 % and 27.72 %, respectively. These results showed that the formation of dipeptide benzoylalanylglycine methyl ester, derived from carboxylic protected glycine and amine protected alanine, increased the corrosion inhibition activity due to the loss of acidity center in the structure of glycine and L-alanine that would induce the corrosive environment towards carbon steel. (author)

  9. Development of fast disintegrating compressed tablets using amino acid as disintegration accelerator: evaluation of wetting and disintegration of tablet on the basis of surface free energy.

    Science.gov (United States)

    Fukami, Jinichi; Ozawa, Asuka; Yoshihashi, Yasuo; Yonemochi, Etsuo; Terada, Katsuhide

    2005-12-01

    A fast disintegrating compressed tablet was formulated using amino acids, such as L-lysine HCl, L-alanine, glycine and L-tyrosine as disintegration accelerator. The tablets having the hardness of about 4 kgf were prepared and the effect of amino acids on the wetting time and disintegration time in the oral cavity of tablets was examined on the basis of surface free energy of amino acids. The wetting time of the tablets increased in the order of L-lysine HCl, L-alanine, glycine and L-tyrosine, whereas the disintegration time in the oral cavity of the tablets increased in the order of L-alanine, glycine, L-lysine HCl and L-tyrosine. These behaviors were well analyzed by the introduction of surface free energy. When the polar component of amino acid was large value or the dispersion component was small value, faster wetting of tablet was observed. When the dispersion component of amino acid was large value or the dispersion component was small value, faster disintegration of tablet was observed, expect of L-tyrosine tablet. The fast disintegration of tablets was explained by the theory presented by Matsumaru.

  10. Spectrophotometric readout for alanine dosimeter to be used for food irradiation applications

    International Nuclear Information System (INIS)

    Ebraheem, S.; Beshir, W.B.; Eid, S.

    2002-01-01

    The electron spin resonance (EPR) readout of radical concentration produced upon irradiation of L-alanine is well known as a transfer dosimetry system for high dose level. The highly cost of EPR/alanine dosimetry system is a serious handicap for large scale routine application to be used in irradiation facilities. In this study, the reaction between L-alanine and 1,4-phenyl diammonium dichloride (PAC) solution produces a complex has a purple color. This complex has a variable absorbance with applied doses in the range from 1-20 kGy. Spectrophotometric evaluation at 368 and 505 nm for the absorbance intensity of this color as well as fluorimetric emission wavelength 435 nm were investigated, as a function of dose. The used method is uncomplicated and very easy for routine application. Evaluation of the dye concentration and the suitable amount of alanine has been studied. Stability of the product complex, for long period of time after the reaction had taken place, was also investigated

  11. Stereospecific assignments of glycine in proteins by stereospecific deuteration and {sup 15}N labeling

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.P.; Curley, R.W. Jr.; Panigot, M.J.; Fesik, S.W. [Ohio State Univ., Columbus, OH (United States)

    1994-12-01

    Stereospecific assignments are important for accurately determining the three-dimensional structures of proteins through the use of multidimensional NMR techniques. It is especially important to stereospecifically assign the glycine {alpha}-protons in proteins because of the potential for different backbone conformations of this residue. These stereospecific assignments are critical for interpreting the {sup 3}J{sub NH,{alpha}H} coupling constants and NOEs involving the glycine {alpha}-protons that determine the conformation of this part of the protein. However, it is often difficult to unambiguously obtain the stereospecific assignments for glycine residues by using only NOE data. In this poster, we present a method for unambiguous, stereospecific assignment of the {alpha}-protons of glycine residues. This method involves synthesis of stereo-specifically deuterated and {sup 15}N-labeled Gly using a slightly modified procedure originally described by Woodard and coworkers for the stereoselective deuteration of glycine. The stereospecifically deuterated and {sup 15}N-labeled Gy has been incorporated into recombinant proteins expressed in both bacterial systems (FKBP) and mammalian cells (u-PA). Two- and three-dimensional isotope-filtered and isotope-edited NMR experiments were used to obtain the stereospecific assignments of the glycine {alpha}-protons for these proteins.

  12. 14N nuclear quadrupole interaction in Cu(II) doped L-alanine

    International Nuclear Information System (INIS)

    Murgich, J.; Calvo, R.; Oseroff, S.B.; Instituto Venezolano de Investigaciones Cientificas, Caracas. Dept. de Quimica)

    1980-01-01

    The 14 N nuclear quadrupole interaction tensor Psub(N) measured by ENDOR in Cu(II) doped L-alanine is analyzed in terms of the Townes and Daily theory assuming a tetra-hedrally bonded N atom. The results of this analysis are compared with those for the 14 N in pure L-alanine and it is found that the principal directions of the Psub(N) tensor are drastically changed upon metal complexation as a consequence of the higher electron affinity of Cu(II) with respect to C and H. Comparison of the corresponding bond populations in pure and Cu(II) doped L-alanine indicates that the Cu draws 0.11 more electron from the N than the substituted H atom. (orig.)

  13. Revised mechanism of d-alanine incorporation into cell wall polymers in Gram-positive bacteria

    Science.gov (United States)

    Reichmann, Nathalie T.; Cassona, Carolina Picarra

    2013-01-01

    Teichoic acids (TAs) are important for growth, biofilm formation, adhesion and virulence of Gram-positive bacterial pathogens. The chemical structures of the TAs vary between bacteria, though they typically consist of zwitterionic polymers that are anchored to either the peptidoglycan layer as in the case of wall teichoic acid (WTA) or the cell membrane and named lipoteichoic acid (LTA). The polymers are modified with d-alanines and a lack of this decoration leads to increased susceptibility to cationic antimicrobial peptides. Four proteins, DltA–D, are essential for the incorporation of d-alanines into cell wall polymers and it has been established that DltA transfers d-alanines in the cytoplasm of the cell onto the carrier protein DltC. However, two conflicting models have been proposed for the remainder of the mechanism. Using a cellular protein localization and membrane topology analysis, we show here that DltC does not traverse the membrane and that DltD is anchored to the outside of the cell. These data are in agreement with the originally proposed model for d-alanine incorporation through a process that has been proposed to proceed via a d-alanine undecaprenyl phosphate membrane intermediate. Furthermore, we found that WTA isolated from a Staphylococcus aureus strain lacking LTA contains only a small amount of d-alanine, indicating that LTA has a role, either direct or indirect, in the efficient d-alanine incorporation into WTA in living cells. PMID:23858088

  14. Rapid mapping of protein functional epitopes by combinatorial alanine scanning

    OpenAIRE

    Weiss, GA; Watanabe, CK; Zhong, A; Goddard, A; Sidhu, SS

    2000-01-01

    A combinatorial alanine-scanning strategy was used to determine simultaneously the functional contributions of 19 side chains buried at the interface between human growth hormone and the extracellular domain of its receptor. A phage-displayed protein library was constructed in which the 19 side chains were preferentially allowed to vary only as the wild type or alanine. The library pool was subjected to binding selections to isolate functional clones, and DNA sequencing was used to determine ...

  15. Mechanism of mercurial inhibition of sodium-coupled alanine uptake in liver plasma membrane vesicles from Raja erinacea

    International Nuclear Information System (INIS)

    Sellinger, M.; Ballatori, N.; Boyer, J.L.

    1991-01-01

    In mammalian hepatocytes the L-alanine carrier contains a sulfhydryl group that is essential for its activity and is inhibited by mercurials. In hepatocytes of the evolutionarily primitive little skate (Raja erinacea), HgCl2 inhibits Na(+)-dependent alanine uptake and Na+/K(+)-ATPase and increase K+ permeability. To distinguish between direct effects of HgCl2 on the Na(+)-alanine cotransporter and indirect effects on membrane permeability, [3H]alanine transport was studied in plasma membrane vesicles. [3H]Alanine uptake was stimulated by an out-to-in Na+ but not K+ gradient and was saturable confirming the presence of Na(+)-alanine cotransport in liver plasma membranes from this species. Preincubation of the vesicles with HgCl2 for 5 min reduced initial rates of Na(+)-dependent but not Na(+)-independent alanine uptake in a dose-dependent manner (10-200 microM). In the presence of equal concentrations of NaCl or KCl inside and outside of the vesicles, 75 microM HgCl2 directly inhibited sodium-dependent alanine-[3H]alanine exchange, demonstrating that HgCl2 directly affected the alanine cotransporter. Inhibition of Na(+)-dependent alanine uptake by 30 microM HgCl2 was reversed by dithiothreitol (1 mM). HgCl2 (10-30 microM) also increased initial rates of 22Na uptake (at 5 sec), whereas 22Na uptake rates were decreased at HgCl2 concentrations greater than 50 microM. Higher concentrations of HgCl2 (100-200 microM) produced nonspecific effects on vesicle integrity. These studies indicate that HgCl2 inhibits Na(+)-dependent alanine uptake in skate hepatocytes by three different concentration-dependent mechanisms: direct interaction with the transporters, dissipation of the driving force (Na+ gradient), and loss of membrane integrity

  16. Interactions of Heterodera glycines, Macrophomina phaseolina, and Mycorrhizal Fungi on Soybean in Kansas.

    Science.gov (United States)

    Winkler, H E; Hetrick, B A; Todd, T C

    1994-12-01

    The impact of naturally occurring arbuscular mycorrhizal fungi on soybean growth and their interaction with Heterodera glycines were evaluated in nematode-infested and uninfested fields in Kansas. Ten soybean cultivars from Maturity Groups III-V with differential susceptibility to H. glycines were treated with the fungicide benomyl to suppress colonization by naturally occurring mycorrhizal fungi and compared with untreated control plots. In H. glycines-infested soil, susceptible cultivars exhibited 39% lower yields, 28% lower colonization by mycorrhizal fungi, and an eightfold increase in colonization by the charcoal rot fungus, Macrophomina phaseolina, compared with resistant cultivars. In the absence of the nematode, susceptible cultivars exhibited 10% lower yields than resistant cultivars, root colonization of resistant vs. susceptible soybean by mycorrhizal fungi varied with sampling date, and there were no differences in colonization by M. phaseolina between resistant and susceptible cultivars. Benomyl application resulted in 19% greater root growth and 9% higher seed yields in H. glycines-infested soil, but did not affect soybean growth and yield in the absence of the nematode. Colonization of soybean roots by mycorrhizal fungi was negatively correlated with H. glycines population densities due to nematode antagonism to the mycorrhizal fungi rather than suppression of nematode populations. Soybean yields were a function of the pathogenic effects of H. glycines and M. phaseolina, and, to a lesser degree, the stimulatory effects of mycorrhizal fungi.

  17. The application of Alanine/ESR dosimetry in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hoon; Lee, Byung Il [Radiation Health Research Institute, Seoul (Korea, Republic of)

    2014-05-15

    Alanine/Electron spin resonance(ESR) has been proven very effective tool which dosimetric characteristics is better suitable than generally used personnel dosimeter for long term dose estimation. L-α-alanine has unusual stability of radiation induced radicals. The fading is known as about 1% a year by IAEA technical documentary. It also has linear signal response on gamma rays over the wide range of dose quantity. Alanine is a kind of unnecessary amino acid in 20 amino acids. Estimation of the accumulated gamma dose is important to predict the life expectancy of cables. However, exact estimation of gamma dose at containment building of NPP is very difficult, because the variability of estimation value is apparently depending on the each installation position in containment building. Especially, some installation positions near reactor change extremely. So, the data from ESR measurement should be checked to the details on referring installation map and pictures.

  18. Optical signal response pf the alanine gel solution for photons and electrons clinical beams

    International Nuclear Information System (INIS)

    Silva, Cleber Feijo; Campos, Leticia Lucente

    2009-01-01

    Alanine gel dosimeter is a new gel material developed at IPEN that presents significant improvement on previous alanine systems developed by Costa (1994). The measure technique is based on the transformation of ferrous ions (Fe 2+ ) in ferric ions (Fe 3+ ) after irradiation. The DL-Alanine (C 3 H 7 NO 2 ) is an aminoacid tissue equivalent that improves the production of ferric ions in the solution. This work aims to study the comparison of optical signal response of the alanine gel solution for photons and electrons clinical beams. It was observed that the calibration factor can be considered independent of quality of the radiation for photons and electrons clinical beams. Therefore, it can be used the same calibration factor for evaluating the absorbed dose in photons and electrons fields in the energy of 6 MeV. Alanine Gel Dosimeter presents good performance and can be useful as alternative dosimeter in the radiotherapy area using MRI technique for 3D dose distribution evaluation. (author)

  19. L-alanine-induced germination in Bacillus licheniformis -the impact of native gerA sequences.

    Science.gov (United States)

    Madslien, Elisabeth H; Granum, Per Einar; Blatny, Janet M; Lindbäck, Toril

    2014-04-22

    L-alanine, acting through the GerA receptor, was recently found to be an efficient germinant in Bacillus licheniformis ATCC14580/DSM13. In this study, we show that several of 46 examined B. licheniformis strains germinate remarkably slower than the type strain when exposed to L-alanine. These strains are not necessarily closely related, as determined by MLST (multi-locus sequence typing). Three of the slow-germinating strains were further examined in order to see whether nucleotide substitutions in the gerA sequences were responsible for the slow L-alanine germination. This was performed by complementing the transformable type strain derivate MW3ΔgerAA with gerA variants from the three slow-germinating strains; NVH1032, NVH1112 and NVH800. A wide selection of B. licheniformis strains was evaluated for L-alanine-induced germination efficiency. Our results show that gerA substitutions could only partially explain why spores of some B. licheniformis strains responded slower than others in the presence of L-alanine.

  20. Radical formation of irradiated α-alanine and N-acetyl alanine with heavy ion beams. Effects of the irradiation temperature

    International Nuclear Information System (INIS)

    Minegishi, Atsuko; Nagasaki, Jun; Mori, Wasuke; Amano, Chikara; Takagi, Shinji; Murakami, Takeshi; Kanai, Tatsuaki; Furusawa, Yoshiya; Iwata, Yoshiyuki

    2003-01-01

    The characteristics of irradiation with C290 MeV/u ion beams were investigated using X-band electron spin resonance (ESR) spectroscopy for a polycrystalline powder of L-α-alanine at from 77K to 310K. The formed main radicals at 190K∼310K were the deamino radical and the decarboxyl radical. Because of the first-derivative ESR, decarboxyl radical showed an expanded spectral width and a lower peak height because of its amino hydrogen and nitrogen than that of the same amount of deamino radical. The ESR of irradiated L-α-alanine predominantly indicates the spectrum of the deamino radical. On the irradiated, L-α-alanine at from 77K to 310K ESR showed 1:4:6:4:1 lines at 220K and at room temperature, which indicate that the methyl group of the radical was rotating. On the other hand, at 77K ESR the spectrum showed nearly 1:5:5:5:1 lines, like the teeth of a saw, on samples irradiated at 270K∼350K (range IV), and 1:4:6:4:1 lines for those irradiated at 180K∼260K (range II and III), respectively. It is considered that the radical conformation of the deamino radical is planar (most stable conformation) on an irradiated sample in range IV, and a pyramidal structure on the irradiated sample in ranges II and III. (author)

  1. Synthesis and Analysis of Methacryloyl-L-Alanine Methyl Ester using fourier Transform Nuclear Magnetic Resonance

    International Nuclear Information System (INIS)

    Tri Darwinto

    2008-01-01

    Methacryloyl-L-alanine methyl ester was synthesized by reacting methacrylic acid with L-alanine methyl ester hydrochloride in triethylamine at temperature of 90 o C. Hydrogel polymer of poly(methacryloyl-L-alanine methyl ester) was much used for diagnosis and therapy of vascular tumor. The molecular structure methacryloyl-L-alanine methyl ester analyzed by fourier transform nuclear magnetic resonance (FT-NMR) for analyzing of carbon atom ( 13 C) using Distortionless Enhancement by Polarization Transfer (DEPT) measurement mode with coupling as well as without coupling from proton atom ( 1 H). Molecular structure analysis result showed that DEPT FT-NMR measurement mode with coupling as well as without coupling from 1 H was very fast, exact and accurate method for molecular analysis of organic compound especially methacryloyl-L-alanine methyl ester. (author)

  2. Serum alanine aminotransferase levels, hematocrit rate and body weight correlations before and after hemodialysis session

    Directory of Open Access Journals (Sweden)

    Edmundo Pessoa Lopes

    2009-01-01

    Full Text Available PURPOSE: To evaluate alanine aminotransferase levels before and after a hemodialysis session and to correlate these values with the hematocrit rate and weight loss during hemodialysis. PATIENTS AND METHODS: The serum alanine aminotransferase levels, hematocrit rate and body weight were measured and correlated before and after a single hemodialysis session for 146 patients with chronic renal failure. An receiver operating characteristic (ROC curve for the serum alanine aminotransferase levels collected before and after hemodialysis was plotted to identify hepatitis C virus-infected patients. RESULTS: The mean weight loss of the 146 patients during hemodialysis was 5.3% (p < 0.001. The mean alanine aminotransferase levels before and after hemodialysis were 18.8 and 23.9 IU/, respectively, denoting a significant 28.1% increase. An equally significant increase of 16.4% in the hematocrit rate also occurred after hemodialysis. The weight loss was inversely correlated with the rise in both the alanine aminotransferase level (r = 0.3; p < 0.001 and hematocrit rate (r = 0.5; p < 0.001. A direct correlation was found between the rise in alanine aminotransferase levels and the hematocrit during the hemodialysis session (r = 0.4; p < 0.001. Based on the ROC curve, the upper limit of the normal alanine aminotransferase level should be reduced by 40% relative to the upper limit of normal if the blood samples are collected before the hemodialysis session or by 60% if blood samples are collected after the session. CONCLUSION: In the present study, significant elevations in the serum alanine aminotransferase levels and hematocrit rates occurred in parallel to a reduction in body weight after the hemodialysis session. These findings suggest that one of the factors for low alanine aminotransferase levels prior to hemodialysis could be hemodilution in patients with chronic renal failure.

  3. Effect of the ionizing radiation on alanine solution for a dosimeter application

    International Nuclear Information System (INIS)

    Abdessamad, Nour El Houda

    2007-01-01

    The amino acid alanine is well known as a dosimetric detector material for high level dosimetry. Its application is based on the formation of radicals by ionising radiation. In this study the effect of several parameters such as: the ionising radiation, the concentration, the dose on the pH, conductivity and the oscillotitrometric answer of L a lanine solution was investigated. The results show that there is a significant production of new species. The formation of these species increases upon increasing dose. The comparison between the repeatability of the used techniques led us to choose of the system alanine/pH and the alanine/conductivity as the most adapted. (Author)

  4. Development of a dosimeter for high doses assessment based on Alanine/EPR

    International Nuclear Information System (INIS)

    Galante, O.L.; Rodrigues, O. Jr.; Campos, L.L.

    2000-01-01

    The increasing use of radiation sources of high activity for industrial and medical applications becomes important the research and the development of detectors and dosimetric methods for quality control of the applied doses. This work presents the current stage of the research at IPEN/CNEN-SP that has as objective the development of a standard dosimetric system for high doses assessment based on the alanine as radiation detector and electron paramagnetic resonance (EPR) as measurement technique. The developed system consists of the cylindrical container built in polyethylene of high density and the detector element based on DL-alanine commercially available. For the detector preparation different binding materials such as paraffin and acetate polyvinyl solution (pva) and also the use of a polyethylene tube of low density with 3.2 mm of external diameter, 2 mm of internal diameter and 30 mm of length were tested to provide the easier preparation method and the most sensitive detector. For the alanine + paraffin detector it was used 80% of alanine and 20% of paraffin, for the alanine + pva detector it was used 70% of alanine and 30% of pva solution, and pure alanine was encapsulated, compacted and sealed in the case of the polyethylene tube. The obtained results with respect to handling, packing and construction easiness showed that the polyethylene tube presents all characteristics to obtain of a good detector element. The validation of the dosimetric system was carried out with gamma radiation of the cobalt-60 with doses in the range between 0.2 Gy to 200 kGy. Type tests such as fading, lowest detection limit, reproducibility and energy dependence of the sign EPR were performed. All measurements were carried out at room temperature using a spectrometer of electron paramagnetic resonance (EPR) Bruker model MXE. Taking into account the results obtained: linearity of the EPR signal between 10 Gy and 50 kGy, reproducibility better than 3%, low fading associated with

  5. The influence of measurement and storage conditions on alanine ESR dosimeters

    International Nuclear Information System (INIS)

    Alexandre, A.C.

    1992-01-01

    Alanine has several desirable properties as an ESR dosemeter e.g. tissue equivalence, low fading and an approximately linear response for doses up to 10 kGy. This work reports on a simple system to produce the alanine dosemeter, the signal intensity for a range of doses and energies, and the effect of the air humidity and the spectrometer settings on the ESR signal. (Author)

  6. Alterations in amino acid levels in mouse brain regions after adjunctive treatment of brexpiprazole with fluoxetine: comparison with (R)-ketamine.

    Science.gov (United States)

    Ma, Min; Ren, Qian; Fujita, Yuko; Yang, Chun; Dong, Chao; Ohgi, Yuta; Futamura, Takashi; Hashimoto, Kenji

    2017-11-01

    Brexpiprazole, a serotonin-dopamine activity modulator, is approved in the USA as an adjunctive therapy to antidepressants for treating major depressive disorders. Similar to the N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine, the combination of brexpiprazole and fluoxetine has demonstrated antidepressant-like effects in animal models of depression. The present study was conducted to examine whether the combination of brexpiprazole and fluoxetine could affect the tissue levels of amino acids [glutamate, glutamine, γ-aminobutyric acid (GABA), D-serine, L-serine, and glycine] that are associated with NMDAR neurotransmission. The tissue levels of amino acids in the frontal cortex, striatum, hippocampus, and cerebellum were measured after a single [or repeated (14 days)] oral administration of vehicle, fluoxetine (10 mg/kg), brexpiprazole (0.1 mg/kg), or a combination of the two drugs. Furthermore, we measured the tissue levels of amino acids after a single administration of the NMDAR antagonist (R)-ketamine. A single injection of the combination of fluoxetine and brexpiprazole significantly increased GABA levels in the striatum, the D-serine/L-serine ratio in the frontal cortex, and the glycine/L-serine ratio in the hippocampus. A repeated administration of the combination significantly altered the tissue levels of amino acids in all regions. Interestingly, a repeated administration of the combination significantly decreased the D-serine/L-serine ratio in the frontal cortex, striatum, and hippocampus. In contrast, a single administration of (R)-ketamine significantly increased the D-serine/L-serine ratio in the frontal cortex. These results suggested that alterations in the tissue levels of these amino acids may be involved in the antidepressant-like effects of the combination of brexpiprazole and fluoxetine.

  7. LOCALIZATION OF POLYSOME-BOUND ALBUMIN AND SERINE DEHYDRATASE IN RAT LIVER CELL FRACTIONS

    Science.gov (United States)

    Ikehara, Yukio; Pitot, Henry C.

    1973-01-01

    The polysomes involved in albumin and serine dehydratase synthesis were identified and localized by the binding to rat liver polysomes of anti-rat serum albumin and anti-serine dehydratase [125I]Fab dimer and monomer. Techniques were developed for the isolation of undegraded free and membrane-bound polysomes and for the preparation of [125I]Fab monomers and dimers from the IgG obtained from the antisera to the two proteins, rat serum albumin and serine dehydratase. The distribution of anti-rat serum albumin [125I]Fab dimer in the polysome profile is in accordance with the size of polysomes that are expected to be synthesizing albumin. By direct precipitation, it has been demonstrated that nascent chains isolated from the membrane-bound polysomes by puromycin were precipitated by anti-rat serum albumin-IgG at a level of 5–6 times those released from free polysomes. Anti-rat serum albumin-[125I]Fab dimer reacted with membrane-bound polysomes almost exclusively compared to the binding of nonimmune, control [125I]Fab dimer; a significant degree of binding of anti-rat serum albumin-[125I]Fab to free polysomes was also obtained. The [125I]Fab dimer made from normal control rabbit serum does not react with polysomes from liver at all and this preparation will not interact with polysomes extracted from tissues that do not synthesize rat serum albumin. Both anti-serine dehydratase-[125I]Fab monomer and dimer react with free and bound polysomes from livers of animals fed a chow diet or those fed a high 90% protein diet and given glucagon. In the latter instance, however, it is clear that the majority of the binding occurs to the bound polysomes. Furthermore, the specificity of this reaction may be further shown by the use of kidney polysomes that do not normally synthesize serine dehydratase. When these latter polysomes are isolated, even after the addition of crude and purified serine dehydratase, no reaction with anti-serine dehydratase-Fab fragments could be

  8. Synthesis and characterization of new polyamides derived from alanine and valine derivatives

    Directory of Open Access Journals (Sweden)

    El-Faham Ayman

    2012-11-01

    Full Text Available Abstract Background Many efforts have been recently devoted to design, investigate and synthesize biocompatible, biodegradable polymers for applications in medicine for either the fabrication of biodegradable devices or as drug delivery systems. Many of them consist of condensation of polymers having incorporated peptide linkages susceptible to enzymatic cleavage. Polyamides (PAs containing α-amino acid residues such as L-leucine, L-alanine and L-phenylalanine have been reported as biodegradable materials. Furthermore, polyamides (PAs derived from C10 and C14 dicarboxylic acids and amide-diamines derived from 1,6-hexanediamine or 1,12-dodecanediamine and L-phenylalanine, L-valyl-L-phenylalanine or L-phenylalanyl-L-valine residues have been reported as biocompatible polymers. We have previously described the synthesis and thermal properties of a new type of polyamides-containing amino acids based on eight new symmetric meta-oriented protected diamines derived from coupling of amino acids namely; Fomc-glycine, Fmoc-alanine, Fomc-valine and Fomc-leucine with m-phenylene diamine or 2,6-diaminopyridine. Results revealed that incorporation of pyridine onto the polymeric backbone of all series decreases the thermal stability. Here we describe another family of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of the polymers. Results We report here the preparation of a new type of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of polymers. The thermal properties of the polymers were evaluated by different techniques. Results revealed that structure-thermal property

  9. Exogenous Glycine Nitrogen Enhances Accumulation of Glycosylated Flavonoids and Antioxidant Activity in Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Xiao Yang

    2017-12-01

    Full Text Available Glycine, the simplest amino acid in nature and one of the most abundant free amino acids in soil, is regarded as a model nutrient in organic nitrogen studies. To date, many studies have focused on the uptake, metabolism and distribution of organic nitrogen in plants, but few have investigated the nutritional performance of plants supplied with organic nitrogen. Lettuce (Lactuca sativa L., one of the most widely consumed leafy vegetables worldwide, is a significant source of antioxidants and bioactive compounds such as polyphenols, ascorbic acid and tocopherols. In this study, two lettuce cultivars, Shenxuan 1 and Lollo Rossa, were hydroponically cultured in media containing 4.5, 9, or 18 mM glycine or 9 mM nitrate (control for 4 weeks, and the levels of health-promoting compounds and antioxidant activity of the lettuce leaf extracts were evaluated. Glycine significantly reduced fresh weight compared to control lettuce, while 9 mM glycine significantly increased fresh weight compared to 4.5 or 18 mM glycine. Compared to controls, glycine (18 mM for Shenxuan 1; 9 mM for Lollo Rossa significantly increased the levels of most antioxidants (including total polyphenols, α-tocopherol and antioxidant activity, suggesting appropriate glycine supply promotes antioxidant accumulation and activity. Glycine induced most glycosylated quercetin derivatives and luteolin derivatives detected and decreased some phenolic acids compared to nitrate treatment. This study indicates exogenous glycine supplementation could be used strategically to promote the accumulation of health-promoting compounds and antioxidant activity of hydroponically grown lettuce, which could potentially improve human nutrition.

  10. Exogenous Glycine Nitrogen Enhances Accumulation of Glycosylated Flavonoids and Antioxidant Activity in Lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Yang, Xiao; Cui, Xiaoxian; Zhao, Li; Guo, Doudou; Feng, Lei; Wei, Shiwei; Zhao, Chao; Huang, Danfeng

    2017-01-01

    Glycine, the simplest amino acid in nature and one of the most abundant free amino acids in soil, is regarded as a model nutrient in organic nitrogen studies. To date, many studies have focused on the uptake, metabolism and distribution of organic nitrogen in plants, but few have investigated the nutritional performance of plants supplied with organic nitrogen. Lettuce ( Lactuca sativa L.), one of the most widely consumed leafy vegetables worldwide, is a significant source of antioxidants and bioactive compounds such as polyphenols, ascorbic acid and tocopherols. In this study, two lettuce cultivars, Shenxuan 1 and Lollo Rossa, were hydroponically cultured in media containing 4.5, 9, or 18 mM glycine or 9 mM nitrate (control) for 4 weeks, and the levels of health-promoting compounds and antioxidant activity of the lettuce leaf extracts were evaluated. Glycine significantly reduced fresh weight compared to control lettuce, while 9 mM glycine significantly increased fresh weight compared to 4.5 or 18 mM glycine. Compared to controls, glycine (18 mM for Shenxuan 1; 9 mM for Lollo Rossa) significantly increased the levels of most antioxidants (including total polyphenols, α-tocopherol) and antioxidant activity, suggesting appropriate glycine supply promotes antioxidant accumulation and activity. Glycine induced most glycosylated quercetin derivatives and luteolin derivatives detected and decreased some phenolic acids compared to nitrate treatment. This study indicates exogenous glycine supplementation could be used strategically to promote the accumulation of health-promoting compounds and antioxidant activity of hydroponically grown lettuce, which could potentially improve human nutrition.

  11. Biological control of Heterodera glycines by spore-forming plant growth-promoting rhizobacteria (PGPR on soybean.

    Directory of Open Access Journals (Sweden)

    Ni Xiang

    Full Text Available Heterodera glycines, the soybean cyst nematode, is the most economically important plant-parasitic nematode on soybean production in the U.S. The objectives of this study were to evaluate the potential of plant growth-promoting rhizobacteria (PGPR strains for mortality of H. glycines J2 in vitro and for reducing nematode population density on soybean in greenhouse, microplot, and field trials. The major group causing mortality to H. glycines in vitro was the genus Bacillus that consisted of 92.6% of the total 663 PGPR strains evaluated. The subsequent greenhouse, microplot, and field trials indicated that B. velezensis strain Bve2 consistently reduced H. glycines cyst population density at 60 DAP. Bacillus mojavensis strain Bmo3 suppressed H. glycines cyst and total H. glycines population density under greenhouse conditions. Bacillus safensis strain Bsa27 and Mixture 1 (Bve2 + Bal13 reduced H. glycines cyst population density at 60 DAP in the field trials. Bacillus subtilis subsp. subtilis strains Bsssu2 and Bsssu3, and B. velezensis strain Bve12 increased early soybean growth including plant height and plant biomass in the greenhouse trials. Bacillus altitudinis strain Bal13 increased early plant growth on soybean in the greenhouse and microplot trials. Mixture 2 (Abamectin + Bve2 + Bal13 increased early plant growth in the microplot trials at 60 DAP, and also enhanced soybean yield at harvest in the field trials. These results demonstrated that individual PGPR strains and mixtures can reduce H. glycines population density in the greenhouse, microplot, and field conditions, and increased yield of soybean.

  12. Biological control of Heterodera glycines by spore-forming plant growth-promoting rhizobacteria (PGPR) on soybean.

    Science.gov (United States)

    Xiang, Ni; Lawrence, Kathy S; Kloepper, Joseph W; Donald, Patricia A; McInroy, John A

    2017-01-01

    Heterodera glycines, the soybean cyst nematode, is the most economically important plant-parasitic nematode on soybean production in the U.S. The objectives of this study were to evaluate the potential of plant growth-promoting rhizobacteria (PGPR) strains for mortality of H. glycines J2 in vitro and for reducing nematode population density on soybean in greenhouse, microplot, and field trials. The major group causing mortality to H. glycines in vitro was the genus Bacillus that consisted of 92.6% of the total 663 PGPR strains evaluated. The subsequent greenhouse, microplot, and field trials indicated that B. velezensis strain Bve2 consistently reduced H. glycines cyst population density at 60 DAP. Bacillus mojavensis strain Bmo3 suppressed H. glycines cyst and total H. glycines population density under greenhouse conditions. Bacillus safensis strain Bsa27 and Mixture 1 (Bve2 + Bal13) reduced H. glycines cyst population density at 60 DAP in the field trials. Bacillus subtilis subsp. subtilis strains Bsssu2 and Bsssu3, and B. velezensis strain Bve12 increased early soybean growth including plant height and plant biomass in the greenhouse trials. Bacillus altitudinis strain Bal13 increased early plant growth on soybean in the greenhouse and microplot trials. Mixture 2 (Abamectin + Bve2 + Bal13) increased early plant growth in the microplot trials at 60 DAP, and also enhanced soybean yield at harvest in the field trials. These results demonstrated that individual PGPR strains and mixtures can reduce H. glycines population density in the greenhouse, microplot, and field conditions, and increased yield of soybean.

  13. Calculations of the relative effectiveness of alanine for neutrons with energies up to 17.1 MeV

    International Nuclear Information System (INIS)

    Gerstenberg, H.M.; Coyne, J.J.

    1990-01-01

    The relative effectiveness (RE) of alanine has been calculated for neutrons using the RE of alanine for charged particles. The neutrons interact with one or more of the elements (hydrogen, carbon, nitrogen and oxygen) that compose the alanine. These interactions produce spectra of secondary charged particles consisting of ions of H, D, He, Be, B, C, N and O. From a combination of the calculated secondary charged particle spectra generated by the slowing down neutrons, and the calculated RE of the ions produced, a RE for the neutrons can be obtained. In addition, lineal energy spectra were determined for neutrons with energies up to 17.1 MeV interacting with alanine. An analytical code was used to calculate these spectra for a 1 μm diameter alanine cell surrounded by an alanine medium. For comparison, similar calculations were made for muscle tissue. Finally, the calculated differential RE was folded with dose distributions to obtain RE-weighted distributions for alanine. (author)

  14. Effects of dose fractionation on the response of alanine dosimetry

    International Nuclear Information System (INIS)

    Lundahl, Brad; Logar, John; Desrosiers, Marc; Puhl, James

    2014-01-01

    Alanine dosimetry is well established as a transfer standard and is becoming more prevalently used in routine dosimetry systems for radiation processing. Many routine measurement applications in radiation processing involve absorbed dose measurements resulting from fractioned exposures to ionizing radiation. Fractioning of absorbed dose is identified as an influence quantity (ISO/ASTM, 2013). This paper reports on study results of absorbed dose fractioning characteristics of alanine for gamma and high energy electron beam radiation sources. The results of this study indicate a radiation response difference due to absorbed dose fractioning in response can be observed after four fractionations for high-energy electron beams and no difference up to seven fractions for gamma rays using an ANOVA evaluation method. - Highlights: • Fractioning effects signaled in electron beam using an ANOVA at 6 equal increments. • Fractioning effects not signaled in gamma using an ANOVA up to 7 equal increments. • Insensitivity of alanine to dose fractioning indicates nominal impact on calibration

  15. First report of the Soybean Cyst Nematode, Heterodera glycines, in New York

    Science.gov (United States)

    The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is the most damaging pathogen of soybean (Glycine max (L.) Merr.), causing more than $1 billion in yield losses annually in the United States (Koenning and Wrather 2010). The SCN distribution map updated in 2014 showed that SCN were dete...

  16. Blood metabolomics analysis identifies abnormalities in the citric acid cycle, urea cycle, and amino acid metabolism in bipolar disorder.

    Science.gov (United States)

    Yoshimi, Noriko; Futamura, Takashi; Kakumoto, Keiji; Salehi, Alireza M; Sellgren, Carl M; Holmén-Larsson, Jessica; Jakobsson, Joel; Pålsson, Erik; Landén, Mikael; Hashimoto, Kenji

    2016-06-01

    Bipolar disorder (BD) is a severe and debilitating psychiatric disorder. However, the precise biological basis remains unknown, hampering the search for novel biomarkers. We performed a metabolomics analysis to discover novel peripheral biomarkers for BD. We quantified serum levels of 116 metabolites in mood-stabilized male BD patients (n = 54) and age-matched male healthy controls (n = 39). After multivariate logistic regression, serum levels of pyruvate, N-acetylglutamic acid, α-ketoglutarate, and arginine were significantly higher in BD patients than in healthy controls. Conversely, serum levels of β-alanine, and serine were significantly lower in BD patients than in healthy controls. Chronic (4-weeks) administration of lithium or valproic acid to adult male rats did not alter serum levels of pyruvate, N-acetylglutamic acid, β-alanine, serine, or arginine, but lithium administration significantly increased serum levels of α-ketoglutarate. The metabolomics analysis demonstrated altered serum levels of pyruvate, N-acetylglutamic acid, β-alanine, serine, and arginine in BD patients. The present findings suggest that abnormalities in the citric acid cycle, urea cycle, and amino acid metabolism play a role in the pathogenesis of BD.

  17. Determination of the carbon, hydrogen and nitrogen contents of alanine and their uncertainties using the certified reference material L-alanine (NMIJ CRM 6011-a).

    Science.gov (United States)

    Itoh, Nobuyasu; Sato, Ayako; Yamazaki, Taichi; Numata, Masahiko; Takatsu, Akiko

    2013-01-01

    The carbon, hydrogen, and nitrogen (CHN) contents of alanine and their uncertainties were estimated using a CHN analyzer and the certified reference material (CRM) L-alanine. The CHN contents and their uncertainties, as measured using the single-point calibration method, were 40.36 ± 0.20% for C, 7.86 ± 0.13% for H, and 15.66 ± 0.09% for N; the results obtained using the bracket calibration method were also comparable. The method described in this study is reasonable, convenient, and meets the general requirement of having uncertainties ≤ 0.4%.

  18. Antibacterial activity of silver nanoparticles synthesized from serine

    Energy Technology Data Exchange (ETDEWEB)

    Jayaprakash, N. [Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034 (India); SRM Valliammai Engineering College, Department of Chemistry, Chennai 603 203 (India); Judith Vijaya, J., E-mail: jjvijayaloyola@yahoo.co.in [Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034 (India); John Kennedy, L. [Materials Division, School of Advanced Sciences, VIT University, Chennai Campus, Chennai 600 048 (India); Priadharsini, K.; Palani, P. [Department of Center for Advanced Study in Botany, University of Madras, Guindy Campus, Chennai 600 025 (India)

    2015-04-01

    Silver nanoparticles (Ag NPs) were synthesized by a simple microwave irradiation method using polyvinyl pyrrolidone (PVP) as a capping agent and serine as a reducing agent. UV–Visible spectra were used to confirm the formation of Ag NPs by observing the surface plasmon resonance (SPR) band at 443 nm. The emission spectrum of Ag NPs showed an emission band at 484 nm. In the presence of microwave radiation, serine acts as a reducing agent, which was confirmed by Fourier transformed infrared (FT-IR) spectrum. High-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning electron microscopy (HR-SEM) were used to investigate the morphology of the synthesized sample. These images showed the sphere-like morphology. The elemental composition of the sample was determined by the energy dispersive X-ray analysis (EDX). Selected area electron diffraction (SAED) was used to find the crystalline nature of the Ag NPs. The electrochemical behavior of the synthesized Ag NPs was analyzed by the cyclic voltammetry (CV). Antibacterial experiments showed that the prepared Ag NPs showed relatively similar antibacterial activities, when compared with AgNO{sub 3} against Gram-positive and Gram-negative bacteria. - Highlights: • Microwave irradiation method is used to synthesize silver nanoparticles. • Highly stable silver nanoparticles are produced from serine. • A detailed study of antibacterial activities is discussed. • Formation mechanism of silver microspheres has been proposed.

  19. Dependence of alanine gel dosimeter response as a function of photon clinical beams dose rate

    International Nuclear Information System (INIS)

    Silva, Cleber Feijo; Campos, Leticia Lucente

    2013-01-01

    Gel dosimetry is a new area developed by Gore, it is ery useful for application in radiotherapy because using NMR imaging as evaluation technique is possible to evaluate three dimensional absorbed dose distribution. The measure technique is based on difference of ferrous (Fe 2+ ) and ferric (Fe 3+ ) ) ions concentration that can be measured also by spectrophotometry technique. The Alanine gel dosimeter was developed at IPEN. The alanine is an amino acid and tissue equivalent material that presents significant improvement on previous alanine dosimetry systems. The addition of Alanine increases the production of ferric ions in the solution. This work aims to study the dose rate dependence of photon clinical beams radiation on the alanine gel dosimeter optical response, as well as the response repeatability and gel production reproducibility, since this property is very important for characterization and standardization of any dosimeter. (author)

  20. Random mutagenesis of human serine racemase reveals residues important for the enzymatic activity

    Czech Academy of Sciences Publication Activity Database

    Hoffman, Hillary Elizabeth; Jirásková, Jana; Zvelebil, M.; Konvalinka, Jan

    2010-01-01

    Roč. 75, č. 1 (2010), s. 59-79 ISSN 0010-0765 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : D-serine * serine racemase * random mutagenesis Subject RIV: CE - Biochemistry Impact factor: 0.853, year: 2010