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Sample records for acid jasmonic acid

  1. Optimized Jasmonic Acid Production by Lasiodiplodia theobromae Reveals Formation of Valuable Plant Secondary Metabolites

    PubMed Central

    Eng, Felipe; Haroth, Sven; Feussner, Kirstin; Meldau, Dorothea; Rekhter, Dmitrij; Ischebeck, Till; Brodhun, Florian

    2016-01-01

    Jasmonic acid is a plant hormone that can be produced by the fungus Lasiodiplodia theobromae via submerged fermentation. From a biotechnological perspective jasmonic acid is a valuable feedstock as its derivatives serve as important ingredients in different cosmetic products and in the future it may be used for pharmaceutical applications. The objective of this work was to improve the production of jasmonic acid by L. theobromae strain 2334. We observed that jasmonic acid formation is dependent on the culture volume. Moreover, cultures grown in medium containing potassium nitrate as nitrogen source produced higher amounts of jasmonic acid than analogous cultures supplemented with ammonium nitrate. When cultivated under optimal conditions for jasmonic acid production, L. theobromae secreted several secondary metabolites known from plants into the medium. Among those we found 3-oxo-2-(pent-2-enyl)-cyclopentane-1-butanoic acid (OPC-4) and hydroxy-jasmonic acid derivatives, respectively, suggesting that fungal jasmonate metabolism may involve similar reaction steps as that of plants. To characterize fungal growth and jasmonic acid-formation, we established a mathematical model describing both processes. This model may form the basis of industrial upscaling attempts. Importantly, it showed that jasmonic acid-formation is not associated to fungal growth. Therefore, this finding suggests that jasmonic acid, despite its enormous amount being produced upon fungal development, serves merely as secondary metabolite. PMID:27907207

  2. Nematocidal effects of natural phytoregulators jasmonic acid and methyl-jasmonate against Pratylenchus zeae and Helicotylenchus spp.

    PubMed

    Gavin, Amanda Salomão; Faggion, Silmara Aparecida; Hernandes, Camila; Lourenço, Mirian Vergínia; França, Suzelei de Castro; Beleboni, Rene Oliveira

    2013-01-01

    The aim of this study was to evaluate the nematocidal effects of natural phytoregulators jasmonic acid (JA) and methyl-jasmonate (MJ) against plant parasitic nematodes Pratylenchus zeae (Graham) (Pratylenchidae) and Helicotylenchus spp. (Hoplolaimidae). Both JA and MJ promoted elevated percentages of mortality in P. zeae and Helicotylenchus spp. after 12 and 24 h of nematodes exposition at different concentrations of jasmonates. Considering the potential use of jasmonates as biofertiliser added now for their nematocidal effects, our results are of relevance in terms of biotechnological application.

  3. Jasmonic acid/methyl jasmonate accumulate in wounded soybean hypocotyls and modulate wound gene expression.

    PubMed

    Creelman, R A; Tierney, M L; Mullet, J E

    1992-06-01

    Jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA), are plant lipid derivatives that resemble mammalian eicosanoids in structure and biosynthesis. These compounds are proposed to play a role in plant wound and pathogen responses. Here we report the quantitative determination of JA/MeJA in planta by a procedure based on the use of [13C,2H3]MeJA as an internal standard. Wounded soybean (Glycine max [L] Merr. cv. Williams) stems rapidly accumulated MeJA and JA. Addition of MeJA to soybean suspension cultures also increased mRNA levels for three wound-responsive genes (chalcone synthase, vegetative storage protein, and proline-rich cell wall protein) suggesting a role for MeJA/JA in the mediation of several changes in gene expression associated with the plants' response to wounding.

  4. Use of jasmonic acid and salicylic acid to inhibit growth of sugarbeet storage rot pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Jasmonic acid (JA) and salicylic acid (SA) are endogenous plant hormones that induce native plant defense responses and provide protection against a wide range of diseases. Previously, JA, applied after harvest, was shown to protect sugarbeet roots against the storage pathogens, Botrytis cinerea, P...

  5. Jasmonic acid signaling modulates ozone-induced hypersensitive cell death.

    PubMed

    Rao, M V; Lee, H; Creelman, R A; Mullet, J E; Davis, K R

    2000-09-01

    Recent studies suggest that cross-talk between salicylic acid (SA)-, jasmonic acid (JA)-, and ethylene-dependent signaling pathways regulates plant responses to both abiotic and biotic stress factors. Earlier studies demonstrated that ozone (O(3)) exposure activates a hypersensitive response (HR)-like cell death pathway in the Arabidopsis ecotype Cvi-0. We now have confirmed the role of SA and JA signaling in influencing O(3)-induced cell death. Expression of salicylate hydroxylase (NahG) in Cvi-0 reduced O(3)-induced cell death. Methyl jasmonate (Me-JA) pretreatment of Cvi-0 decreased O(3)-induced H(2)O(2) content and SA concentrations and completely abolished O(3)-induced cell death. Cvi-0 synthesized as much JA as did Col-0 in response to O(3) exposure but exhibited much less sensitivity to exogenous Me-JA. Analyses of the responses to O(3) of the JA-signaling mutants jar1 and fad3/7/8 also demonstrated an antagonistic relationship between JA- and SA-signaling pathways in controlling the magnitude of O(3)-induced HR-like cell death.

  6. Lipoxygenase in Caragana jubata responds to low temperature, abscisic acid, methyl jasmonate and salicylic acid.

    PubMed

    Bhardwaj, Pardeep Kumar; Kaur, Jagdeep; Sobti, Ranbir Chander; Ahuja, Paramvir Singh; Kumar, Sanjay

    2011-09-01

    Lipoxygenase (LOX) catalyses oxygenation of free polyunsaturated fatty acids into oxylipins, and is a critical enzyme of the jasmonate signaling pathway. LOX has been shown to be associated with biotic and abiotic stress responses in diverse plant species, though limited data is available with respect to low temperature and the associated cues. Using rapid amplification of cDNA ends, a full-length cDNA (CjLOX) encoding lipoxygenase was cloned from apical buds of Caragana jubata, a temperate plant species that grows under extreme cold. The cDNA obtained was 2952bp long consisting of an open reading frame of 2610bp encoding 869 amino acids protein. Multiple alignment of the deduced amino acid sequence with those of other plants demonstrated putative LH2/ PLAT domain, lipoxygenase iron binding catalytic domain and lipoxygenase_2 signature sequences. CjLOX exhibited up- and down-regulation of gene expression pattern in response to low temperature (LT), abscisic acid (ABA), methyl jasmonate (MJ) and salicylic acid (SA). Among all the treatments, a strong up-regulation was observed in response to MJ. Data suggests an important role of jasmonate signaling pathway in response to LT in C. jubata.

  7. Jasmonic acid involves in grape fruit ripening and resistant against Botrytis cinerea.

    PubMed

    Jia, Haifeng; Zhang, Cheng; Pervaiz, Tariq; Zhao, Pengcheng; Liu, Zhongjie; Wang, Baoju; Wang, Chen; Zhang, Lin; Fang, Jinggui; Qian, Jianpu

    2016-01-01

    Fruit ripening is a complex process that is regulated by a signal network. Whereas the regulatory mechanism of abscisic acid has been studied extensively in non-climacteric fruit, little is know about other signaling pathways involved in this process. In this study, we performed that plant hormone jasmonic acid plays an important role in grape fruit coloring and softening by increasing the transcription levels of several ripening-related genes, such as the color-related genes PAL1, DFR, CHI, F3H, GST, CHS, and UFGT; softening-related genes PG, PL, PE, Cell, EG1, and XTH1; and aroma-related genes Ecar, QR, and EGS. Lastly, the fruit anthocyanin, phenol, aroma, and cell wall materials were changed. Jasmonic acid positively regulated its biosynthesis pathway genes LOS, AOS, and 12-oxophytodienoate reductase (OPR) and signal pathway genes COI1 and JMT. RNA interference of grape jasmonic acid pathway gene VvAOS in strawberry fruit appeared fruit un-coloring phenotypes; exogenous jasmonic acid rescued this phenotypes. On the contrary, overexpression of grape jasmonic acid receptor VvCOI1 in the strawberry fruit accelerated the fruit-ripening process and induced some plant defense-related gene expression level. Furthermore, jasmonic acid treatment or strong jasmonic acid signal pathway in strawberry fruit make the fruit resistance against Botrytis cinerea.

  8. Plants on constant alert: elevated levels of jasmonic acid and jasmonate-induced transcripts in caterpillar resistant maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant defense responses against insect herbivores frequently depend on the biosynthesis and action of jasmonic acid (JA) and its conjugates. To better understand JA signaling pathways in maize (Zea mays L.), we have examined two maize genotypes, Mp708 and Tx601. Mp708 is resistant to feeding by le...

  9. Quantification of jasmonic and salicylic acids in rice seedling leaves.

    PubMed

    Cho, Kyoungwon; Han, Oksoo; Tamogami, Shigeru; Shibato, Junko; Kubo, Akihiro; Agrawal, Ganesh Kumar; Rakwal, Randeep

    2013-01-01

    Jasmonic acid (JA) and salicylic acid (SA) are critical signaling components involved in various aspects of plant growth, development, and defense. Their constitutive levels vary from plant to plant and also from tissue to tissue within the same plant. Moreover, their quantitative levels change when plant is exposed to biotic and abiotic stresses. To better understand the JA- and SA-mediated signaling and metabolic pathways, it is important to precisely quantify their levels in plants/tissues/organs. However, their extraction and quantification are not trivial and still technically challenging. An effort has been made in various laboratories to develop a simple and standard procedure that can be utilized for quantification of JA and SA. Here, we present the experimental procedure and our decade of experience on extracting and quantifying them in an absolute manner in leaves of rice seedlings. We must mention that this method has been applied to both monocotyledonous and dicotyledonous plants for absolute quantification of JA and SA. As collaboration is the key towards rapid progress in science and technology, we are always open to sharing our experience in this field with any active research group with an aim to improve the procedure further and eventually to connect the importance of their (JA and SA) quantitative levels with networks of signaling and metabolic pathways in plants.

  10. Jasmonic acid and salicylic acid activate a common defense system in rice

    PubMed Central

    Tamaoki, Daisuke; Seo, Shigemi; Yamada, Shoko; Kano, Akihito; Miyamoto, Ayumi; Shishido, Hodaka; Miyoshi, Seika; Taniguchi, Shiduku; Akimitsu, Kazuya; Gomi, Kenji

    2013-01-01

    Jasmonic acid (JA) and salicylic acid (SA) play important roles in plant defense systems. JA and SA signaling pathways interact antagonistically in dicotyledonous plants, but, the status of crosstalk between JA and SA signaling is unknown in monocots. Our rice microarray analysis showed that more than half of the genes upregulated by the SA analog BTH are also upregulated by JA, suggesting that a major portion of the SA-upregulated genes are regulated by JA-dependent signaling in rice. A common defense system that is activated by both JA and SA is thus proposed which plays an important role in pathogen defense responses in rice. PMID:23518581

  11. Altered cultivar resistance of kimchi cabbage seedlings mediated by salicylic Acid, jasmonic Acid and ethylene.

    PubMed

    Lee, Young Hee; Kim, Sang Hee; Yun, Byung-Wook; Hong, Jeum Kyu

    2014-09-01

    Two cultivars Buram-3-ho (susceptible) and CR-Hagwang (moderate resistant) of kimchi cabbage seedlings showed differential defense responses to anthracnose (Colletotrichum higginsianum), black spot (Alternaria brassicicola) and black rot (Xanthomonas campestris pv. campestris, Xcc) diseases in our previous study. Defense-related hormones salicylic acid (SA), jasmonic acid (JA) and ethylene led to different transcriptional regulation of pathogenesis-related (PR) gene expression in both cultivars. In this study, exogenous application of SA suppressed basal defenses to C. higginsianum in the 1st leaves of the susceptible cultivar and cultivar resistance of the 2nd leaves of the resistant cultivar. SA also enhanced susceptibility of the susceptible cultivar to A. brassicicola. By contrast, SA elevated disease resistance to Xcc in the resistant cultivar, but not in the susceptible cultivar. Methyl jasmonate (MJ) treatment did not affect the disease resistance to C. higginsianum and Xcc in either cultivar, but it compromised the disease resistance to A. brassicicola in the resistant cultivar. Treatment with 1-aminocyclopropane-1-carboxylic acid (ACC) ethylene precursor did not change resistance of the either cultivar to C. higginsianum and Xcc. Effect of ACC pretreatment on the resistance to A. brassicicola was not distinguished between susceptible and resistant cultivars, because cultivar resistance of the resistant cultivar was lost by prolonged moist dark conditions. Taken together, exogenously applied SA, JA and ethylene altered defense signaling crosstalk to three diseases of anthracnose, black spot and black rot in a cultivar-dependent manner.

  12. Identification of jasmonic acid and its methyl ester as gum-inducing factors in tulips.

    PubMed

    Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi

    2005-02-01

    The purpose of this study was to identify endogenous factors that induce gummosis and to show their role in gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) stems. Using procedures to detect endogenous factors that induce gum in the stem of tulips, jasmonic acid (JA) and methyl jasmonate (JA-Me) were successfully identified using gas-liquid chromatography-mass spectrometry. Total amounts of JA and JA-Me designated as jasmonates in tulip stems were also estimated at about 70-80 ng/g fresh weight, using deuterium-labeled jasmonates as internal standards. The application of JA and JA-Me as lanolin pastes substantially induced gums in tulip stems with ethylene production. The application of ethephon, an ethylene-generating compound, however, induced no gummosis although it slightly affected jasmonate content in tulip stems. These results strongly suggest that JA and JA-Me are endogenous factors that induce gummosis in tulip stems.

  13. Silverleaf Whitefly Induces Salicylic Acid Defenses and Suppresses Effectual Jasmonic Acid Defenses1[W][OA

    PubMed Central

    Zarate, Sonia I.; Kempema, Louisa A.; Walling, Linda L.

    2007-01-01

    The basal defenses important in curtailing the development of the phloem-feeding silverleaf whitefly (Bemisia tabaci type B; SLWF) on Arabidopsis (Arabidopsis thaliana) were investigated. Sentinel defense gene RNAs were monitored in SLWF-infested and control plants. Salicylic acid (SA)-responsive gene transcripts accumulated locally (PR1, BGL2, PR5, SID2, EDS5, PAD4) and systemically (PR1, BGL2, PR5) during SLWF nymph feeding. In contrast, jasmonic acid (JA)- and ethylene-dependent RNAs (PDF1.2, VSP1, HEL, THI2.1, FAD3, ERS1, ERF1) were repressed or not modulated in SLWF-infested leaves. To test for a role of SA and JA pathways in basal defense, SLWF development on mutant and transgenic lines that constitutively activate or impair defense pathways was determined. By monitoring the percentage of SLWF nymphs in each instar, we show that mutants that activate SA defenses (cim10) or impair JA defenses (coi1) accelerated SLWF nymphal development. Reciprocally, mutants that activate JA defenses (cev1) or impair SA defenses (npr1, NahG) slowed SLWF nymphal development. Furthermore, when npr1 plants, which do not activate downstream SA defenses, were treated with methyl jasmonate, a dramatic delay in nymph development was observed. Collectively, these results showed that SLWF-repressed, JA-regulated defenses were associated with basal defense to the SLWF. PMID:17189328

  14. Silverleaf whitefly induces salicylic acid defenses and suppresses effectual jasmonic acid defenses.

    PubMed

    Zarate, Sonia I; Kempema, Louisa A; Walling, Linda L

    2007-02-01

    The basal defenses important in curtailing the development of the phloem-feeding silverleaf whitefly (Bemisia tabaci type B; SLWF) on Arabidopsis (Arabidopsis thaliana) were investigated. Sentinel defense gene RNAs were monitored in SLWF-infested and control plants. Salicylic acid (SA)-responsive gene transcripts accumulated locally (PR1, BGL2, PR5, SID2, EDS5, PAD4) and systemically (PR1, BGL2, PR5) during SLWF nymph feeding. In contrast, jasmonic acid (JA)- and ethylene-dependent RNAs (PDF1.2, VSP1, HEL, THI2.1, FAD3, ERS1, ERF1) were repressed or not modulated in SLWF-infested leaves. To test for a role of SA and JA pathways in basal defense, SLWF development on mutant and transgenic lines that constitutively activate or impair defense pathways was determined. By monitoring the percentage of SLWF nymphs in each instar, we show that mutants that activate SA defenses (cim10) or impair JA defenses (coi1) accelerated SLWF nymphal development. Reciprocally, mutants that activate JA defenses (cev1) or impair SA defenses (npr1, NahG) slowed SLWF nymphal development. Furthermore, when npr1 plants, which do not activate downstream SA defenses, were treated with methyl jasmonate, a dramatic delay in nymph development was observed. Collectively, these results showed that SLWF-repressed, JA-regulated defenses were associated with basal defense to the SLWF.

  15. Short- and long-term changes in sugarbeet (Beta vulgaris L.) gene expression after postharvest jasmonic acid treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Jasmonic acid is a natural plant hormone that induces native defense responses in plants. Sugarbeet (Beta vulgaris L.) root unigenes that were differentially expressed 2 and 60 days after a postharvest jasmonic acid treatment are presented. Data include changes in unigene expression relative to wate...

  16. Induced production of 1-methoxy-indol-3-ylmethyl glucosinolate by jasmonic acid and methyl jasmonate in sprouts and leaves of pak choi (Brassica rapa ssp. chinensis).

    PubMed

    Wiesner, Melanie; Hanschen, Franziska S; Schreiner, Monika; Glatt, Hansruedi; Zrenner, Rita

    2013-07-18

    Pak choi plants (Brassica rapa ssp. chinensis) were treated with different signaling molecules methyl jasmonate, jasmonic acid, linolenic acid, and methyl salicylate and were analyzed for specific changes in their glucosinolate profile. Glucosinolate levels were quantified using HPLC-DAD-UV, with focus on induction of indole glucosinolates and special emphasis on 1-methoxy-indol-3-ylmethyl glucosinolate. Furthermore, the effects of the different signaling molecules on indole glucosinolate accumulation were analyzed on the level of gene expression using semi-quantitative realtime RT-PCR of selected genes. The treatments with signaling molecules were performed on sprouts and mature leaves to determine ontogenetic differences in glucosinolate accumulation and related gene expression. The highest increase of indole glucosinolate levels, with considerable enhancement of the 1-methoxy-indol-3-ylmethyl glucosinolate content, was achieved with treatments of sprouts and mature leaves with methyl jasmonate and jasmonic acid. This increase was accompanied by increased expression of genes putatively involved in the indole glucosinolate biosynthetic pathway. The high levels of indole glucosinolates enabled the plant to preferentially produce the respective breakdown products after tissue damage. Thus, pak choi plants treated with methyl jasmonate or jasmonic acid, are a valuable tool to analyze the specific protection functions of 1-methoxy-indole-3-carbinole in the plants defense strategy in the future.

  17. Effect of methyl jasmonate, salicylic acid, Headline and Stadium on sucrose yield and storage properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methyl jasmonate (MeJA) and salicylic acid (SA) have been reported to enhance yield and protect crop plants and products against abiotic stresses and diseases. The effect of these compounds on sugarbeets, however, is unknown. Research was conducted in 2015 and 2016 to investigate the effects of an e...

  18. Manipulating anthocyanin composition in Vitis vinifera suspension cultures by elicitation with jasmonic acid and light irradiation.

    PubMed

    Curtin, Chris; Zhang, Wei; Franco, Chris

    2003-07-01

    Jasmonic acid altered the accumulation of major anthocyanins in Vitis vinifera cell culture. Peonidin 3-glucoside content at day three was increased from 0.3 to 1.7 mg g(-1) dry cell wt while other major anthocyanins were increased by smaller increments. By day 14, the content of methylated and acylated anthocyanins (peonidin 3-p-coumaroylglucoside and malvidin 3-p-coumaroylglucoside) was 6.3 mg g(-1) DCW, in response to treatment with jasmonic acid, and comprising approximately 45% (w/w) of total anthocyanins. In comparison, the untreated control culture contained 1.2 mg g(-1) DCW which made up approximately 32% (w/w) of total anthocyanins. Light further enhanced anthocyanin accumulation induced by jasmonic acid elicitation. The content of peonidin 3-glucoside at day 3 was 6.6 mg g(-1) DCW, 22-fold higher than control cultures while the content in response to light irradiation alone was 0.6 mg g(-1) DCW. When a highly pigmented cell line was elicited with jasmonic acid total anthocyanins increased from 9.2 to 20.7 mg g(-1) DCW, but there was no change in the anthocyanin composition.

  19. Integrating nitric oxide into salicylic acid and jasmonic acid/ ethylene plant defense pathways.

    PubMed

    Mur, Luis A J; Prats, Elena; Pierre, Sandra; Hall, Michael A; Hebelstrup, Kim H

    2013-01-01

    Plant defense against pests and pathogens is known to be conferred by either salicylic acid (SA) or jasmonic acid (JA)/ethylene (ET) pathways, depending on infection or herbivore-grazing strategy. It is well attested that SA and JA/ET pathways are mutually antagonistic allowing defense responses to be tailored to particular biotic stresses. Nitric oxide (NO) has emerged as a major signal influencing resistance mediated by both signaling pathways but no attempt has been made to integrate NO into established SA/JA/ET interactions. NO has been shown to act as an inducer or suppressor of signaling along each pathway. NO will initiate SA biosynthesis and nitrosylate key cysteines on TGA-class transcription factors to aid in the initiation of SA-dependent gene expression. Against this, S-nitrosylation of NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1) will promote the NPR1 oligomerization within the cytoplasm to reduce TGA activation. In JA biosynthesis, NO will initiate the expression of JA biosynthetic enzymes, presumably to over-come any antagonistic effects of SA on JA-mediated transcription. NO will also initiate the expression of ET biosynthetic genes but a suppressive role is also observed in the S-nitrosylation and inhibition of S-adenosylmethionine transferases which provides methyl groups for ET production. Based on these data a model for NO action is proposed but we have also highlighted the need to understand when and how inductive and suppressive steps are used.

  20. Integrating nitric oxide into salicylic acid and jasmonic acid/ ethylene plant defense pathways

    PubMed Central

    Mur, Luis A. J.; Prats, Elena; Pierre, Sandra; Hall, Michael A.; Hebelstrup, Kim H.

    2013-01-01

    Plant defense against pests and pathogens is known to be conferred by either salicylic acid (SA) or jasmonic acid (JA)/ethylene (ET) pathways, depending on infection or herbivore-grazing strategy. It is well attested that SA and JA/ET pathways are mutually antagonistic allowing defense responses to be tailored to particular biotic stresses. Nitric oxide (NO) has emerged as a major signal influencing resistance mediated by both signaling pathways but no attempt has been made to integrate NO into established SA/JA/ET interactions. NO has been shown to act as an inducer or suppressor of signaling along each pathway. NO will initiate SA biosynthesis and nitrosylate key cysteines on TGA-class transcription factors to aid in the initiation of SA-dependent gene expression. Against this, S-nitrosylation of NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1) will promote the NPR1 oligomerization within the cytoplasm to reduce TGA activation. In JA biosynthesis, NO will initiate the expression of JA biosynthetic enzymes, presumably to over-come any antagonistic effects of SA on JA-mediated transcription. NO will also initiate the expression of ET biosynthetic genes but a suppressive role is also observed in the S-nitrosylation and inhibition of S-adenosylmethionine transferases which provides methyl groups for ET production. Based on these data a model for NO action is proposed but we have also highlighted the need to understand when and how inductive and suppressive steps are used. PMID:23818890

  1. AtWRKY22 promotes susceptibility to aphids and modulates salicylic acid and jasmonic acid signalling

    PubMed Central

    Kloth, Karen J.; Wiegers, Gerrie L.; Busscher-Lange, Jacqueline; van Haarst, Jan C.; Kruijer, Willem; Bouwmeester, Harro J.; Dicke, Marcel; Jongsma, Maarten A.

    2016-01-01

    Aphids induce many transcriptional perturbations in their host plants, but the signalling cascades responsible and the effects on plant resistance are largely unknown. Through a genome-wide association (GWA) mapping study in Arabidopsis thaliana, we identified WRKY22 as a candidate gene associated with feeding behaviour of the green peach aphid, Myzus persicae. The transcription factor WRKY22 is known to be involved in pathogen-triggered immunity, and WRKY22 gene expression has been shown to be induced by aphids. Assessment of aphid population development and feeding behaviour on knockout mutants and overexpression lines showed that WRKY22 increases susceptibility to M. persicae via a mesophyll-located mechanism. mRNA sequencing analysis of aphid-infested wrky22 knockout plants revealed the up-regulation of genes involved in salicylic acid (SA) signalling and down-regulation of genes involved in plant growth and cell-wall loosening. In addition, mechanostimulation of knockout plants by clip cages up-regulated jasmonic acid (JA)-responsive genes, resulting in substantial negative JA–SA crosstalk. Based on this and previous studies, WRKY22 is considered to modulate the interplay between the SA and JA pathways in response to a wide range of biotic and abiotic stimuli. Its induction by aphids and its role in suppressing SA and JA signalling make WRKY22 a potential target for aphids to manipulate host plant defences. PMID:27107291

  2. Transcriptome Analysis in Haematococcus pluvialis: Astaxanthin Induction by Salicylic Acid (SA) and Jasmonic Acid (JA).

    PubMed

    Gao, Zhengquan; Li, Yan; Wu, Guanxun; Li, Guoqiang; Sun, Haifeng; Deng, Suzhen; Shen, Yicheng; Chen, Guoqiang; Zhang, Ruihao; Meng, Chunxiao; Zhang, Xiaowen

    2015-01-01

    Haematococcus pluvialis is an astaxanthin-rich microalga that can increase its astaxanthin production by salicylic acid (SA) or jasmonic acid (JA) induction. The genetic transcriptome details of astaxanthin biosynthesis were analyzed by exposing the algal cells to 25 mg/L of SA and JA for 1, 6 and 24 hours, plus to the control (no stress). Based on the RNA-seq analysis, 56,077 unigenes (51.7%) were identified with functions in response to the hormone stress. The top five identified subcategories were cell, cellular process, intracellular, catalytic activity and cytoplasm, which possessed 5600 (~9.99%), 5302 (~9.45%), 5242 (~9.35%), 4407 (~7.86%) and 4195 (~7.48%) unigenes, respectively. Furthermore, 59 unigenes were identified and assigned to 26 putative transcription factors (TFs), including 12 plant-specific TFs. They were likely associated with astaxanthin biosynthesis in Haematococcus upon SA and JA stress. In comparison, the up-regulation of differential expressed genes occurred much earlier, with higher transcript levels in the JA treatment (about 6 h later) than in the SA treatment (beyond 24 h). These results provide valuable information for directing metabolic engineering efforts to improve astaxanthin biosynthesis in H. pluvialis.

  3. Oxylipin Signaling: A Distinct Role for the Jasmonic Acid Precursor cis-(+)-12-Oxo-Phytodienoic Acid (cis-OPDA)

    PubMed Central

    Dave, Anuja; Graham, Ian A.

    2012-01-01

    Oxylipins are lipid-derived compounds, many of which act as signals in the plant response to biotic and abiotic stress. They include the phytohormone jasmonic acid (JA) and related jasmonate metabolites cis-(+)-12-oxo-phytodienoic acid (cis-OPDA), methyl jasmonate, and jasmonoyl-L-isoleucine (JA-Ile). Besides the defense response, jasmonates are involved in plant growth and development and regulate a range of processes including glandular trichome development, reproduction, root growth, and senescence. cis-OPDA is known to possess a signaling role distinct from JA-Ile. The non-enzymatically derived phytoprostanes are structurally similar to cis-OPDA and induce a common set of genes that are not responsive to JA in Arabidopsis thaliana. A novel role for cis-OPDA in seed germination regulation has recently been uncovered based on evidence from double mutants and feeding experiments showing that cis-OPDA interacts with abscisic acid (ABA), inhibits seed germination, and increases ABA INSENSITIVE5 (ABI5) protein abundance. Large amounts of cis-OPDA are esterified to galactolipids in A. thaliana and the resulting compounds, known as Arabidopsides, are thought to act as a rapidly available source of cis-OPDA. PMID:22645585

  4. Defense signaling among interconnected ramets of a rhizomatous clonal plant, induced by jasmonic-acid application

    NASA Astrophysics Data System (ADS)

    Chen, Jin-Song; Lei, Ning-Fei; Liu, Qing

    2011-07-01

    Resource sharing between ramets of clonal plants is a well-known phenomenon that allows stoloniferous and rhizomatous species to internally transport water, mineral nutrients and carbohydrates from sites of high supply to sites of high demand. Moreover, vascular ramet connections are likely to provide an excellent means to share substances other than resources, such as defense signals. In a greenhouse experiment, the rhizomatous sedge Carex alrofusca, consisting of integrated ramets of different ages, was used to study the transmission of defense signals through belowground rhizome connections in response to local spray with jasmonic-acid. A feeding preference test with the caterpillar Gynaephora rnenyuanensis was employed to assess benefits of rhizome connections on defense signaling. Young ramets were more responsive to jasmonic-acid treatment than middle-aged or old ramets. Condensed tannin content in the foliage of young ramets showed a significant increase and soluble carbohydrate and nitrogen content showed marginally significant decreases in the 1 mM jasmonic-acid treatment but not in control and/or 0.0001 mM jasmonic-acid treatments. The caterpillar G. rnenyuanensis preferentially grazed young ramets. After a localized spray of 1 mM jasmonic-acid, the leaf area of young ramets consumed by herbivores was greatly reduced. We propose that defense signals may be transmitted through physical connections (stolon or rhizome) among interconnected ramets of clonal plants. Induced resistance to herbivory may selectively enhance the protection of more vulnerable and valuable plant tissues and confer a significant benefit to clonal plants by a modular risk-spreading strategy, equalizing ontogenetic differences of unevenly-aged ramets in chemical defense compounds and nutritional properties of tissue.

  5. Antagonistic effects of abscisic acid and jasmonates on salt stress-inducible transcripts in rice roots.

    PubMed Central

    Moons, A; Prinsen, E; Bauw, G; Van Montagu, M

    1997-01-01

    Abscisic acid (ABA) and jasmonates have been implicated in responses to water deficit and wounding. We compared the molecular and physiological effects of jasmonic acid (JA) (< or = 10 microM), ABA, and salt stress in roots of rice. JA markedly induced a cationic peroxidase, two novel 32- and 28-kD proteins, acidic PR-1 and PR-10 pathogenesis-related proteins, and the salt stress-responsive SalT protein in roots. Most JA-responsive proteins (JIPs) from roots also accumulated when plants were subjected to salt stress. None of the JIPs accumulated when plants were treated with ABA. JA did not induce an ABA-responsive group 3 late-embryogenesis abundant (LEA) protein. Salt stress and ABA but not JA induced oslea3 transcript accumulation. By contrast, JA, ABA, and salt stress induced transcript accumulation of salT and osdrr, which encodes a rice PR-10 protein. However, ABA also negatively affected salT transcript accumulation, whereas JA negatively affected ABA-induced oslea3 transcript levels. Endogenous root ABA and methyl jasmonate levels showed a differential increase with the dose and the duration of salt stress. The results indicate that ABA and jasmonates antagonistically regulated the expression of salt stress-inducible proteins associated with water deficit or defense responses. PMID:9437865

  6. Activation of the Jasmonic Acid Plant Defence Pathway Alters the Composition of Rhizosphere Bacterial Communities

    PubMed Central

    Carvalhais, Lilia C.; Dennis, Paul G.; Badri, Dayakar V.; Tyson, Gene W.; Vivanco, Jorge M.; Schenk, Peer M.

    2013-01-01

    Jasmonic acid (JA) signalling plays a central role in plant defences against necrotrophic pathogens and herbivorous insects, which afflict both roots and shoots. This pathway is also activated following the interaction with beneficial microbes that may lead to induced systemic resistance. Activation of the JA signalling pathway via application of methyl jasmonate (MeJA) alters the composition of carbon containing compounds released by roots, which are implicated as key determinants of rhizosphere microbial community structure. In this study, we investigated the influence of the JA defence signalling pathway activation in Arabidopsis thaliana on the structure of associated rhizosphere bacterial communities using 16S rRNA gene amplicon pyrosequencing. Application of MeJA did not directly influence bulk soil microbial communities but significant changes in rhizosphere community composition were observed upon activation of the jasmonate signalling pathway. Our results suggest that JA signalling may mediate plant-bacteria interactions in the soil upon necrotrophic pathogen and herbivorous insect attacks. PMID:23424661

  7. Endogenous Bioactive Jasmonate Is Composed of a Set of (+)-7-iso-JA-Amino Acid Conjugates.

    PubMed

    Yan, Jianbin; Li, Suhua; Gu, Min; Yao, Ruifeng; Li, Yuwen; Chen, Juan; Yang, Mai; Tong, Jianhua; Xiao, Langtao; Nan, Fajun; Xie, Daoxin

    2016-12-01

    Jasmonates (JAs) regulate a wide range of plant defense and development processes. The bioactive JA is perceived by its receptor COI1 to trigger the degradation of JASMONATE ZIM-DOMAIN (JAZ) proteins and subsequently derepress the JAZ-repressed transcription factors for activation of expression of JA-responsive genes. So far, (+)-7-iso-JA-l-Ile has been the only identified endogenous bioactive JA molecule. Here, we designed coronafacic acid (CFA) conjugates with all the amino acids (CFA-AA) to mimic the JA amino acid conjugates, and revealed that (+)-7-iso-JA-Leu, (+)-7-iso-JA-Val, (+)-7-iso-JA-Met, and (+)-7-iso-JA-Ala are new endogenous bioactive JA molecules. Furthermore, our studies uncover the general characteristics for all the bioactive JA molecules, and provide a new strategy to synthetically generate novel active JA molecules.

  8. Molecular and biochemical characterization of the jasmonic acid methyltransferase gene from black cottonwood (Populus trichocarpa)

    SciTech Connect

    Zhao, Nan; Yao, Jianzhuang; Chaiprasongsuk, Minta; Li, Guanglin; Guan, Ju; Tschaplinski, Timothy J; Guo, Hong; Chen, Feng

    2013-01-01

    Methyl jasmonate is a metabolite known to be produced by many plants and has roles in diverse biological processes. It is biosynthesized by the action of S-adenosyl-L-methionine:jasmonic acid carboxyl methyltransferase (JMT), which belongs to the SABATH family of methyltransferases. Herein is reported the isolation and biochemical characterization of a JMT gene from black cottonwood (Populus trichocarpa). The genome of P. trichocarpa contains 28 SABATH genes (PtSABATH1 to PtSABATH28). Recombinant PtSABATH3 expressed in Escherichia coli showed the highest level of activity with jasmonic acid (JA) among carboxylic acids tested. It was therefore renamed PtJMT1. PtJMT1 also displayed activity with benzoic acid (BA), with which the activity was about 22% of that with JA. PtSABATH2 and PtSABATH4 were most similar to PtJMT1 among all PtSABATHs. However, neither of them had activity with JA. The apparent Km values of PtJMT1 using JA and BA as substrate were 175 lM and 341 lM, respectively. Mutation of Ser-153 and Asn-361, two residues in the active site of PtJMT1, to Tyr and Ser respectively, led to higher specific activity with BA than with JA. Homology-based structural modeling indicated that substrate alignment, in which Asn-361 is involved, plays a role in determining the substrate specificity of PtJMT1. In the leaves of young seedlings of black cottonwood, the expression of PtJMT1 was induced by plant defense signal molecules methyl jasmonate and salicylic acid and a fungal elicitor alamethicin, suggesting that PtJMT1 may have a role in plant defense against biotic stresses. Phylogenetic analysis suggests that PtJMT1 shares a common ancestor with the Arabidopsis JMT, and functional divergence of these two apparent JMT orthologs has occurred since the split of poplar and Arabidopsis lineages.

  9. Lasiojasmonates A-C, three jasmonic acid esters produced by Lasiodiplodia sp., a grapevine pathogen.

    PubMed

    Andolfi, Anna; Maddau, Lucia; Cimmino, Alessio; Linaldeddu, Benedetto T; Basso, Sara; Deidda, Antonio; Serra, Salvatorica; Evidente, Antonio

    2014-07-01

    In this study, a strain (BL 101) of a species of Lasiodiplodia, not yet formally described, which was isolated from declining grapevine plants showing wedge-shaped cankers, was investigated for its ability to produce in vitro bioactive secondary metabolites. From culture filtrates of this strain three jasmonic acid esters, named lasiojasmonates A-C and 16-O-acetylbotryosphaerilactones A and C were isolated together with (1R,2R)-jasmonic acid, its methyl ester, botryosphaerilactone A, (3S,4R,5R)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone and (3R,4S)-botryodiplodin. The structures of lasiojasmonates A-C were established by spectroscopic methods as (1R*,2R*,3'S*,4'R*,5'R*)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone, (1R*,2R*,3'S*,4'R*,5'R*,10'R*,12'R*,13'R*,14'S*) and (1R*,2R*,3'S*,4'R*,5'R*,10'S*,12'R*,13'R*,14'S*)-4-(4-hydroxymethyl-3,5-dimethyltetrahydro-furan-2-yloxymethyl)-3,5-dimethyldihydro-2-furanones jasmonates (1, 4 and 5). The structures of 16-O-acetylbotryosphaerilactones A and C were determined by comparison of their spectral data with those of the corresponding acetyl derivatives obtained by acetylation of botryosphaerilactone A. The metabolites isolated, except 4 and 5, were tested at 1mg/mL on leaves of grapevine cv. Cannonau and cork oak using the leaf puncture assay. They were also tested on detached grapevine leaves at 0.5mg/mL and tomato cuttings at 0.1mg/mL. In all phytotoxic assays only jasmonic acid was found to be active. All metabolites were inactive in the zootoxic assay at 50 μg/mL.

  10. A Jasmonate ZIM-Domain Protein NaJAZd Regulates Floral Jasmonic Acid Levels and Counteracts Flower Abscission in Nicotiana attenuata Plants

    PubMed Central

    Oh, Youngjoo; Baldwin, Ian T.; Galis, Ivan

    2013-01-01

    Jasmonic acid is an important regulator of plant growth, development and defense. The jasmonate-ZIM domain (JAZ) proteins are key regulators in jasmonate signaling ubiquitously present in flowering plants but their functional annotation remains largely incomplete. Recently, we identified 12 putative JAZ proteins in native tobacco, Nicotiana attenuata, and initiated systematic functional characterization of these proteins by reverse genetic approaches. In this report, Nicotiana attenuata plants silenced in the expression of NaJAZd (irJAZd) by RNA interference were used to characterize NaJAZd function. Although NaJAZd transcripts were strongly and transiently up-regulated in the rosette leaves by simulated herbivory treatment, we did not observe strong defense-related phenotypes, such as altered herbivore performance or the constitutive accumulation of defense-related secondary metabolites in irJAZd plants compared to wild type plants, both in the glasshouse and the native habitat of Nicotiana attenuata in the Great Basin Desert, Utah, USA. Interestingly, irJAZd plants produced fewer seed capsules than did wild type plants as a result of increased flower abscission in later stages of flower development. The early- and mid-developmental stages of irJAZd flowers had reduced levels of jasmonic acid and jasmonoyl-L-isoleucine, while fully open flowers had normal levels, but these were impaired in NaMYB305 transcript accumulations. Previously, NaMYB305-silenced plants were shown to have strong flower abscission phenotypes and contained lower NECTARIN 1 transcript levels, phenotypes which are copied in irJAZd plants. We propose that the NaJAZd protein is required to counteract flower abscission, possibly by regulating jasmonic acid and jasmonoyl-L-isoleucine levels and/or expression of NaMYB305 gene in Nicotiana attenuata flowers. This novel insight into the function of JAZ proteins in flower and seed development highlights the diversity of functions played by jasmonates

  11. Low oleic acid-derived repression of jasmonic acid-inducible defense responses requires the WRKY50 and WRKY51 proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Signaling induced upon a reduction in oleic acid (18:1) levels simultaneously up-regulates salicylic acid (SA)-mediated responses and inhibits jasmonic acid (JA)-inducible defenses, resulting in enhanced resistance to biotrophs but increased susceptibility to necrotrophs. SA and the signaling compon...

  12. Effects of jasmonic acid signalling on the wheat microbiome differ between body sites

    PubMed Central

    Liu, Hongwei; Carvalhais, Lilia C.; Schenk, Peer M.; Dennis, Paul G.

    2017-01-01

    Jasmonic acid (JA) signalling helps plants to defend themselves against necrotrophic pathogens and herbivorous insects and has been shown to influence the root microbiome of Arabidopsis thaliana. In this study, we determined whether JA signalling influences the diversity and functioning of the wheat (Triticum aestivum) microbiome and whether these effects are specific to particular parts of the plant. Activation of the JA pathway was achieved via exogenous application of methyl jasmonate and was confirmed by significant increases in the abundance of 10 JA-signalling-related gene transcripts. Phylogenetic marker gene sequencing revealed that JA signalling reduced the diversity and changed the composition of root endophytic but not shoot endophytic or rhizosphere bacterial communities. The total enzymatic activity and substrate utilisation profiles of rhizosphere bacterial communities were not affected by JA signalling. Our findings indicate that the effects of JA signalling on the wheat microbiome are specific to individual plant compartments. PMID:28134326

  13. The anti-ageing potential of a new jasmonic acid derivative (LR2412): in vitro evaluation using reconstructed epidermis Episkin™.

    PubMed

    Michelet, Jean F; Olive, Christian; Rieux, Elodie; Fagot, Dominique; Simonetti, Lucie; Galey, Jean B; Dalko-Csiba, Maria; Bernard, Bruno A; Pereira, Rui

    2012-05-01

    Jasmonic acid is involved in plant wound repair and tissue regeneration, but no study has been reported in human skin. The effect of a jasmonic acid derivative, tetra-hydro-jasmonic acid (LR2412, 1 and 10 μm) was investigated on an in vitro reconstructed skin model, Episkin™. Using real time RTQPCR studies, results showed an increase in hyaluronan synthase 2 (HAS2) and hyaluronase synthase 3 (HAS3) expression. Furthermore, an increase in hyaluronic acid (HA) deposits in basal and suprabasal layers of the epidermis was observed. The percentage of positive Ki67 keratinocytes in the basal layer as well as the epidermis thickness were seen to increase. Immunohistochemistry studies showed that the synthesis of late differentiation proteins filaggrin and transglutaminase 1 was not modified. The human epidermis is known to thin with age while HA content has been reported to decrease. These results illustrate the potential of LR2412 in counteracting signs of skin ageing.

  14. Triacontanol negatively modulates the jasmonic acid-stimulated proteinase inhibitors in tomato (Lycopersicon esculentum).

    PubMed

    Ramanarayan, Krishnamurthy; Swamy, Gangadharamurthy Sivakumar

    2004-04-01

    Triacontanol (TRIA), a long chain aliphatic alcohol (C30H61OH) reverses the effect of jasmonic acid (JA) in inducing proteinase inhibitors (PIs) in tomato leaves. Porcine pancreas trypsin and Spodoptera litura gut proteinases were inhibited in the presence of leaf proteins treated with JA, and TRIA partially reverses this effect. Spodoptera litura larvae fed with tomato leaves treated with JA were reduced in body weight and TRIA is able to partially reverse this JA-induced effect. These results reflect the partial reversal effect of TRIA in down regulating the JA-induced production of proteinase inhibitors.

  15. Chemical and biological characterization of cinnamic acid derivatives from cell cultures of lavender (Lavandula officinalis) induced by stress and jasmonic acid.

    PubMed

    Nitzsche, Astrid; Tokalov, Sergey V; Gutzeit, Herwig O; Ludwig-Müller, Jutta

    2004-05-19

    Cell cultures of lavender (Lavandula officinalis) were analyzed for the metabolite profile under normal growth conditions and under stress as well as after jasmonic acid treatment. The main compound synthesized was rosmarinic acid, which was also secreted into the culture medium. Different solvent extraction methods at different pH values altered the profile slightly. Anoxic stress induced the synthesis of a cinnamic acid derivative, which was identified as caffeic acid by gas chromatography-mass spectrometry. Caffeic acid was also induced after treatment of the cell cultures with jasmonic acid. Although the antioxidative activity of both compounds, rosmarinic acid and caffeic acid, was confirmed in an assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH), it was demonstrated that both substances have a low cytotoxic potential in vitro using acute myeloid leukemia (HL-60) cells. The potential of the system for finding new bioactive compounds is discussed.

  16. Ectopic expression of Arabidopsis genes encoding salicylic acid- and jasmonic acid-related proteins confers partial resistance to soybean cyst nematode (Heterodera glycines) in transgenic soybean roots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background. Extensive studies using the model system Arabidopsis thaliana to elucidate plant defense signaling and pathway networks indicate that salicylic acid (SA) is the key hormone triggering the plant defense response against biotrophic and hemi-biotrophic pathogens, while jasmonic acid (JA) an...

  17. Methyl jasmonate stimulates biosynthesis of 2-phenylethylamine, phenylacetic acid and 2-phenylethanol in seedlings of common buckwheat.

    PubMed

    Horbowicz, Marcin; Wiczkowski, Wiesław; Sawicki, Tomasz; Szawara-Nowak, Dorota; Sytykiewicz, Hubert; Mitrus, Joanna

    2015-01-01

    Methyl jasmonate has a strong effect on secondary metabolizm in plants, by stimulating the biosynthesis a number of phenolic compounds and alkaloids. Common buckwheat (Fagopyrum esculentum Moench) is an important source of biologically active compounds. This research focuses on the detection and quantification of 2-phenylethylamine and its possible metabolites in the cotyledons, hypocotyl and roots of common buckwheat seedlings treated with methyl jasmonate. In cotyledons of buckwheat sprouts, only traces of 2-phenylethylamine were found, while in the hypocotyl and roots its concentration was about 150 and 1000-times higher, respectively. Treatment with methyl jasmonate resulted in a 4-fold increase of the 2-phenylethylamine level in the cotyledons of 7-day buckwheat seedlings, and an 11-fold and 5-fold increase in hypocotyl and roots, respectively. Methyl jasmonate treatment led also to about 4-fold increase of phenylacetic acid content in all examined seedling organs, but did not affect the 2-phenylethanol level in cotyledons, and slightly enhanced in hypocotyl and roots. It has been suggested that 2-phenylethylamine is a substrate for the biosynthesis of phenylacetic acid and 2-phenylethanol, as well as cinnamoyl 2-phenethylamide. In organs of buckwheat seedling treated with methyl jasmonate, higher amounts of aromatic amino acid transaminase mRNA were found. The enzyme can be involved in the synthesis of phenylpyruvic acid, but the presence of this compound could not be confirmed in any of the examined organs of common buckwheat seedling.

  18. Jasmonic acid is a crucial signal transducer in heat shock induced sesquiterpene formation in Aquilaria sinensis.

    PubMed

    Xu, Yan-Hong; Liao, Yong-Cui; Zhang, Zheng; Liu, Juan; Sun, Pei-Wen; Gao, Zhi-Hui; Sui, Chun; Wei, Jian-He

    2016-02-23

    Agarwood, a highly valuable resinous and fragrant heartwood of Aquilaria plants, is widely used in traditional medicines, incense and perfume. Only when Aquilaria trees are wounded by external stimuli do they form agarwood sesquiterpene defensive compounds. Therefore, understanding the signaling pathway of wound-induced agarwood formation is important. Jasmonic acid (JA) is a well-characterized molecule that mediates a plant's defense response and secondary metabolism. However, little is known about the function of endogenous JA in agarwood sesquiterpene biosynthesis. Here, we report that heat shock can up-regulate the expression of genes in JA signaling pathway, induce JA production and the accumulation of agarwood sesquiterpene in A. sinensis cell suspension cultures. A specific inhibitor of JA, nordihydroguaiaretic acid (NDGA), could block the JA signaling pathway and reduce the accumulation of sesquiterpene compounds. Additionally, compared to SA and H2O2, exogenously supplied methyl jasmonate has the strongest stimulation effect on the production of sesquiterpene compounds. These results clearly demonstrate the central induction role of JA in heat-shock-induced sesquiterpene production in A. sinensis.

  19. Jasmonic acid is a crucial signal transducer in heat shock induced sesquiterpene formation in Aquilaria sinensis

    PubMed Central

    Xu, Yan-Hong; Liao, Yong-Cui; Zhang, Zheng; Liu, Juan; Sun, Pei-Wen; Gao, Zhi-Hui; Sui, Chun; Wei, Jian-He

    2016-01-01

    Agarwood, a highly valuable resinous and fragrant heartwood of Aquilaria plants, is widely used in traditional medicines, incense and perfume. Only when Aquilaria trees are wounded by external stimuli do they form agarwood sesquiterpene defensive compounds. Therefore, understanding the signaling pathway of wound-induced agarwood formation is important. Jasmonic acid (JA) is a well-characterized molecule that mediates a plant’s defense response and secondary metabolism. However, little is known about the function of endogenous JA in agarwood sesquiterpene biosynthesis. Here, we report that heat shock can up-regulate the expression of genes in JA signaling pathway, induce JA production and the accumulation of agarwood sesquiterpene in A. sinensis cell suspension cultures. A specific inhibitor of JA, nordihydroguaiaretic acid (NDGA), could block the JA signaling pathway and reduce the accumulation of sesquiterpene compounds. Additionally, compared to SA and H2O2, exogenously supplied methyl jasmonate has the strongest stimulation effect on the production of sesquiterpene compounds. These results clearly demonstrate the central induction role of JA in heat-shock-induced sesquiterpene production in A. sinensis. PMID:26902148

  20. Jasmonic acid enhances plant cyanogenesis and resistance to herbivory in lima bean.

    PubMed

    Kautz, Stefanie; Trisel, Julie A; Ballhorn, Daniel J

    2014-12-01

    Jasmonic acid (JA) is a natural plant hormone ubiquitously distributed in plants and centrally involved in the induction of direct and indirect plant defenses. Defenses up-regulated by this hormone include trichomes--a direct, mechanical defense--and alkaloids--a direct chemical defense--as well as two indirect chemical defenses: volatile organic compounds (VOCs) and extrafloral nectar (EFN). Plant cyanogenesis--the release of toxic hydrogen cyanide (HCN) from preformed cyanogenic precursors in fruits, leaves, and seeds of many plants--is recognized as a direct, constitutive plant defensive trait, and is among the most widely distributed of all direct chemical plant defenses. The cyanogenic system in plants is composed of three parameters: The cyanogenic potential (HCNp; concentration of cyanogenic precursors), β-glucosidase activity, and cyanogenic capacity (HCNc; release of gaseous hydrogen cyanide). Here, we demonstrated that experimental application of aqueous solutions of JA ranging from 0.001 to 1.0 mmol L(-1), as well as insect herbivory significantly enhanced HCNc via the induction of β-glucosidase activity in wild lima bean (Phaseolus lunatus L.). In choice feeding trials with JA induced and damaged leaves, adult Mexican bean beetles--natural herbivores of lima bean--rejected leaves with enhanced β-glucosidase activity and HCNc. Our findings suggest that jasmonic acid plays a critical role in regulating activity of β-glucosidases, which determines the rate of cyanogenesis, and thus mediates direct plant defense against herbivores.

  1. Effects of Jasmonic Acid on Embryo-Specific Processes in Brassica and Linum Oilseeds 1

    PubMed Central

    Wilen, Ronald W.; van Rooijen, Gijs J. H.; Pearce, David W.; Pharis, Richard P.; Holbrook, Larry A.; Moloney, Maurice M.

    1991-01-01

    A number of effects on embryogenesis of the putative phytohormone jasmonic acid (JA), and its methyl ester (MeJA), were investigated in two oilseed plants, repeseed (Brassica napus) and flax (Linum usitatissimum). Results from treatments with JA and MeJA were compared with those of a known effector of several aspects of embryogenesis, abscisic acid (ABA). Jasmonic acid was identified by gas chromatography-mass spectrometry as a naturally occurring substance in both plant species during embryo development. Both JA and MeJA can prevent precocious germination of B. napus microspore embryos and of cultured zygotic embryos of both species at an exogenous concentration of >1 micromolar. This dose-response was comparable with results obtained with ABA. Inhibitory effects were also observed on seed germination with all three growth regulators in rapeseed and flax. A number of molecular aspects of embryogenesis were also investigated. Expression of the B. napus storage protein genes (napin and cruciferin) was induced in both microspore embryos and zygotic embryos by the addition of 10 micromolar JA. The level of napin and cruciferin mRNA detected was similar to that observed when 10 micromolar ABA was applied to these embryos. For MeJA only slight increases in napin or cruciferin mRNA were observed at concentrations of 30 micromolar. Several oilbody-associated proteins were found to accumulate when the embryos were incubated with either JA or ABA in both species. The MeJA had little effect on oilbody protein synthesis. The implications of JA acting as a natural regulator of gene expression in zygotic embryogenesis are discussed. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:16667997

  2. Jasmonic acid carboxyl methyltransferase regulates development and herbivory-induced defense response in rice.

    PubMed

    Qi, Jinfeng; Li, Jiancai; Han, Xiu; Li, Ran; Wu, Jianqiang; Yu, Haixin; Hu, Lingfei; Xiao, Yutao; Lu, Jing; Lou, Yonggen

    2016-06-01

    Jasmonic acid (JA) and related metabolites play a key role in plant defense and growth. JA carboxyl methyltransferase (JMT) may be involved in plant defense and development by methylating JA to methyl jasmonate (MeJA) and thus influencing the concentrations of JA and related metabolites. However, no JMT gene has been well characterized in monocotyledon defense and development at the molecular level. After we cloned a rice JMT gene, OsJMT1, whose encoding protein was localized in the cytosol, we found that the recombinant OsJMT1 protein catalyzed JA to MeJA. OsJMT1 is up-regulated in response to infestation with the brown planthopper (BPH; Nilaparvata lugens). Plants in which OsJMT1 had been overexpressed (oe-JMT plants) showed reduced height and yield. These oe-JMT plants also exhibited increased MeJA levels but reduced levels of herbivore-induced JA and jasmonoyl-isoleucine (JA-Ile). The oe-JMT plants were more attractive to BPH female adults but showed increased resistance to BPH nymphs, probably owing to the different responses of BPH female adults and nymphs to the changes in levels of H2 O2 and MeJA in oe-JMT plants. These results indicate that OsJMT1, by altering levels of JA and related metabolites, plays a role in regulating plant development and herbivore-induced defense responses in rice.

  3. Simultaneous determination of shikimic acid, salicylic acid and jasmonic acid in wild and transgenic Nicotiana langsdorffii plants exposed to abiotic stresses.

    PubMed

    Scalabrin, Elisa; Radaelli, Marta; Capodaglio, Gabriele

    2016-06-01

    The presence and relative concentration of phytohormones may be regarded as a good indicator of an organism's physiological state. The integration of the rolC gene from Agrobacterium rhizogenes and of the rat glucocorticoid receptor (gr) in Nicotiana langsdorffii Weinmann plants has shown to determine various physiological and metabolic effects. The analysis of wild and transgenic N. langsdorffii plants, exposed to different abiotic stresses (high temperature, water deficit, and high chromium concentrations) was conducted, in order to investigate the metabolic effects of the inserted genes in response to the applied stresses. The development of a new analytical procedure was necessary, in order to assure the simultaneous determination of analytes and to obtain an adequately low limit of quantification. For the first time, a sensitive HPLC-HRMS quantitative method for the simultaneous determination of salicylic acid, jasmonic acid and shikimic acid was developed and validated. The method was applied to 80 plant samples, permitting the evaluation of plant stress responses and highlighting some metabolic mechanisms. Salicylic, jasmonic and shikimic acids proved to be suitable for the comprehension of plant stress responses. Chemical and heat stresses showed to induce the highest changes in plant hormonal status, differently affecting plant response. The potential of each genetic modification toward the applied stresses was marked and particularly the resistance of the gr modified plants was evidenced. This work provides new information in the study of N. langsdorffii and transgenic organisms, which could be useful for the further application of these transgenes.

  4. Salicylic acid and jasmonic acid are essential for systemic resistance against tobacco mosaic virus in Nicotiana benthamiana.

    PubMed

    Zhu, Feng; Xi, De-Hui; Yuan, Shu; Xu, Fei; Zhang, Da-Wei; Lin, Hong-Hui

    2014-06-01

    Systemic resistance is induced by pathogens and confers protection against a broad range of pathogens. Recent studies have indicated that salicylic acid (SA) derivative methyl salicylate (MeSA) serves as a long-distance phloem-mobile systemic resistance signal in tobacco, Arabidopsis, and potato. However, other experiments indicate that jasmonic acid (JA) is a critical mobile signal. Here, we present evidence suggesting both MeSA and methyl jasmonate (MeJA) are essential for systemic resistance against Tobacco mosaic virus (TMV), possibly acting as the initiating signals for systemic resistance. Foliar application of JA followed by SA triggered the strongest systemic resistance against TMV. Furthermore, we use a virus-induced gene-silencing-based genetics approach to investigate the function of JA and SA biosynthesis or signaling genes in systemic response against TMV infection. Silencing of SA or JA biosynthetic and signaling genes in Nicotiana benthamiana plants increased susceptibility to TMV. Genetic experiments also proved the irreplaceable roles of MeSA and MeJA in systemic resistance response. Systemic resistance was compromised when SA methyl transferase or JA carboxyl methyltransferase, which are required for MeSA and MeJA formation, respectively, were silenced. Moreover, high-performance liquid chromatography-mass spectrometry analysis indicated that JA and MeJA accumulated in phloem exudates of leaves at early stages and SA and MeSA accumulated at later stages, after TMV infection. Our data also indicated that JA and MeJA could regulate MeSA and SA production. Taken together, our results demonstrate that (Me)JA and (Me)SA are required for systemic resistance response against TMV.

  5. [Analysis of the molecular motif for inducing response to jasmonic acid and ethylene in Pib promoter via rice transformation].

    PubMed

    Yu, Li; Yang, Shi-Hu; Jin, Yu-Kuan; Wan, Jian-Min; Zhao, Bao-Quan

    2010-01-01

    The expression of Pib gene in rice was induced by hormone, such as jasmonic acid and ethylene. In order to determine the necessary regions of sequence or motifs for response to jasmonic acid and ethylene in Pib promoter, the full length promoter of Pib (-3,572 approximately 2 bp) and three different 5' deletion fragments of Pib promoter (-2,692 approximately 2 bp, -1,335 approximately 2 bp, -761 approximately 2 bp) were synthesized by PCR and then were substituted for 35S upstream gus in a binary plasmid to construct re-combined plasmids of Pib promoter-gus fusions. Transgenic rice plants of the four recombined plasmids were produced by Agrobacterium-mediated transformation. Quality and quantum analysis of gus activities in transgenic plants at both protein and mRNA levels were conducted. The promotion activity of the full length promoter of Pib (-3,572 approximately 2 bp, pNAR901) was the highest in the four recombinants and the gus activities in its transgenic plant organs were enhanced obviously at 6 h after treatment with jasmonic acid or ethylene. The promotion activity of the deleted Pib promoters was significantly decreased and the response to jasmonic acid or ethylene treatment was not present when the -3,572 approximately -2,692 bp sequence was knocked out from the Pib promoter. Although the disparity in the lengths of the deleted Pib promoter of pNAR902 (-2,692 approximately 2 bp), pNAR903 (-1,335 approximately 2 bp), and pNAR904 (-761 approximately 2 bp) was more than 2 or 3 times, the response to jasmonic acid or ethylene treatment was not different among their transgenic plants. All these results indicated that the common deleted sequences (-3,572 approximately -2,692 bp) in the three deleted Pib promoter constructs were the essential region to the response to jasmonic acid and ethylene treatment. The result of pib promoter sequence searching indicated that there was only one GCCGCC motif at -2,722 bp of this common deleted segment in the Pib promoter

  6. The plastidial retrograde signal methyl erythritol cyclopyrophosphate is a regulator of salicylic acid and jasmonic acid crosstalk.

    PubMed

    Lemos, Mark; Xiao, Yanmei; Bjornson, Marta; Wang, Jin-Zheng; Hicks, Derrick; Souza, Amancio de; Wang, Chang-Quan; Yang, Panyu; Ma, Shisong; Dinesh-Kumar, Savithramma; Dehesh, Katayoon

    2016-03-01

    The exquisite harmony between hormones and their corresponding signaling pathways is central to prioritizing plant responses to simultaneous and/or successive environmental trepidations. The crosstalk between jasmonic acid (JA) and salicylic acid (SA) is an established effective mechanism that optimizes and tailors plant adaptive responses. However, the underlying regulatory modules of this crosstalk are largely unknown. Global transcriptomic analyses of mutant plants (ceh1) with elevated levels of the stress-induced plastidial retrograde signaling metabolite 2-C-methyl-D-erythritol cyclopyrophosphate (MEcPP) revealed robustly induced JA marker genes, expected to be suppressed by the presence of constitutively high SA levels in the mutant background. Analyses of a range of genotypes with varying SA and MEcPP levels established the selective role of MEcPP-mediated signal(s) in induction of JA-responsive genes in the presence of elevated SA. Metabolic profiling revealed the presence of high levels of the JA precursor 12-oxo-phytodienoic acid (OPDA), but near wild type levels of JA in the ceh1 mutant plants. Analyses of coronatine-insensitive 1 (coi1)/ceh1 double mutant plants confirmed that the MEcPP-mediated induction is JA receptor COI1 dependent, potentially through elevated OPDA. These findings identify MEcPP as a previously unrecognized central regulatory module that induces JA-responsive genes in the presence of high SA, thereby staging a multifaceted plant response within the environmental context.

  7. New Clothes for the Jasmonic Acid Receptor COI1: Delayed Abscission, Meristem Arrest and Apical Dominance

    PubMed Central

    Kim, Joonyup; Dotson, Bradley; Rey, Camila; Lindsey, Joshua; Bleecker, Anthony B.; Binder, Brad M.; Patterson, Sara E.

    2013-01-01

    In a screen for delayed floral organ abscission in Arabidopsis, we have identified a novel mutant of CORONATINE INSENSITIVE 1 (COI1), the F-box protein that has been shown to be the jasmonic acid (JA) co-receptor. While JA has been shown to have an important role in senescence, root development, pollen dehiscence and defense responses, there has been little focus on its critical role in floral organ abscission. Abscission, or the detachment of organs from the main body of a plant, is an essential process during plant development and a unique type of cell separation regulated by endogenous and exogenous signals. Previous studies have indicated that auxin and ethylene are major plant hormones regulating abscission; and here we show that regulation of floral organ abscission is also controlled by jasmonic acid in Arabidopsis thaliana. Our characterization of coi1-1 and a novel allele (coi1-37) has also revealed an essential role in apical dominance and floral meristem arrest. In this study we provide genetic evidence indicating that delayed abscission 4 (dab4-1) is allelic to coi1-1 and that meristem arrest and apical dominance appear to be evolutionarily divergent functions for COI1 that are governed in an ecotype-dependent manner. Further characterizations of ethylene and JA responses of dab4-1/coi1-37 also provide new information suggesting separate pathways for ethylene and JA that control both floral organ abscission and hypocotyl growth in young seedlings. Our study opens the door revealing new roles for JA and its interaction with other hormones during plant development. PMID:23573263

  8. A chloroplast lipoxygenase is required for wound-induced jasmonic acid accumulation in Arabidopsis.

    PubMed

    Bell, E; Creelman, R A; Mullet, J E

    1995-09-12

    Plant lipoxygenases are thought to be involved in the biosynthesis of lipid-derived signaling molecules. The potential involvement of a specific Arabidopsis thaliana lipoxygenase isozyme, LOX2, in the biosynthesis of the plant growth regulators jasmonic acid (JA) and abscisic acid was investigated. Our characterization of LOX2 indicates that the protein is targeted to chloroplasts. The physiological role of this chloroplast lipoxygenase was analyzed in transgenic plants where cosuppression reduced LOX2 accumulation. The reduction in LOX2 levels caused no obvious changes in plant growth or in the accumulation of abscisic acid. However, the wound-induced accumulation of JA observed in control plants was absent in leaves of transgenic plants that lacked LOX2. Thus, LOX2 is required for the wound-induced synthesis of the plant growth regulator JA in leaves. We also examined the expression of a wound- and JA-inducible Arabidopsis gene, vsp, in transgenic and control plants. Leaves of transgenic plants lacking LOX2 accumulated less vsp mRNA than did control leaves in response to wounding. This result suggests that wound-induced JA (or some other LOX2-requiring component of the wound response pathway) is involved in the wound-induced regulation of this gene.

  9. Metabolomics Analysis and Biosynthesis of Rosmarinic Acid in Agastache rugosa Kuntze Treated with Methyl Jasmonate

    PubMed Central

    Uddin, Md. Romij; Xu, Hui; Park, Woo Tae; Tuan, Pham Anh; Li, Xiaohua; Chung, Eunsook; Lee, Jai-Heon; Park, Sang Un

    2013-01-01

    This study investigated the effect of methyl jasmonate (MeJA) on metabolic profiles and rosmarinic acid (RA) biosynthesis in cell cultures of Agastache rugosa Kuntze. Transcript levels of phenylpropanoid biosynthetic genes, i.e., ArPAL, Ar4CL, and ArC4H, maximally increased 4.5-fold, 3.4-fold, and 3.5-fold, respectively, compared with the untreated controls, and the culture contained relatively high amounts of RA after exposure of cells to 50 µM MeJA. RA levels were 2.1-, 4.7-, and 3.9-fold higher after exposure to 10, 50, and 100 µM MeJA, respectively, than those in untreated controls. In addition, the transcript levels of genes attained maximum levels at different time points after the initial exposure. The transcript levels of ArC4H and Ar4CL were transiently induced by MeJA, and reached a maximum of up to 8-fold at 3 hr and 6 hr, respectively. The relationships between primary metabolites and phenolic acids in cell cultures of A. rugosa treated with MeJA were analyzed by gas chromatography coupled with time-of-flight mass spectrometry. In total, 45 metabolites, including 41 primary metabolites and 4 phenolic acids, were identified from A. rugosa. Metabolite profiles were subjected to partial least square-discriminate analysis to evaluate the effects of MeJA. The results indicate that both phenolic acids and precursors for the phenylpropanoid biosynthetic pathway, such as aromatic amino acids and shikimate, were induced as a response to MeJA treatment. Therefore, MeJA appears to have an important impact on RA accumulation, and the increased RA accumulation in the treated cells might be due to activation of the phenylpropanoid genes ArPAL, ArC4H, and Ar4CL. PMID:23724034

  10. RNA-seq based transcriptomic analysis uncovers α-linolenic acid and jasmonic acid biosynthesis pathways respond to cold acclimation in Camellia japonica

    PubMed Central

    Li, Qingyuan; Lei, Sheng; Du, Kebing; Li, Lizhi; Pang, Xufeng; Wang, Zhanchang; Wei, Ming; Fu, Shao; Hu, Limin; Xu, Lin

    2016-01-01

    Camellia is a well-known ornamental flower native to Southeast of Asia, including regions such as Japan, Korea and South China. However, most species in the genus Camellia are cold sensitive. To elucidate the cold stress responses in camellia plants, we carried out deep transcriptome sequencing of ‘Jiangxue’, a cold-tolerant cultivar of Camellia japonica, and approximately 1,006 million clean reads were generated using Illumina sequencing technology. The assembly of the clean reads produced 367,620 transcripts, including 207,592 unigenes. Overall, 28,038 differentially expressed genes were identified during cold acclimation. Detailed elucidation of responses of transcription factors, protein kinases and plant hormone signalling-related genes described the interplay of signal that allowed the plant to fine-tune cold stress responses. On the basis of global gene regulation of unsaturated fatty acid biosynthesis- and jasmonic acid biosynthesis-related genes, unsaturated fatty acid biosynthesis and jasmonic acid biosynthesis pathways were deduced to be involved in the low temperature responses in C. japonica. These results were supported by the determination of the fatty acid composition and jasmonic acid content. Our results provide insights into the genetic and molecular basis of the responses to cold acclimation in camellia plants. PMID:27819341

  11. Tomato susceptibility to root-knot nematodes requires an intact jasmonic acid signaling pathway.

    PubMed

    Bhattarai, Kishor K; Xie, Qi-Guang; Mantelin, Sophie; Bishnoi, Usha; Girke, Thomas; Navarre, Duroy A; Kaloshian, Isgouhi

    2008-09-01

    Responses of resistant (Mi-1/Mi-1) and susceptible (mi-1/ mi-1) tomato (Solanum lycopersicum) to root-knot nematodes (RKNs; Meloidogyne spp.) infection were monitored using cDNA microarrays, and the roles of salicylic acid (SA) and jasmonic acid (JA) defense signaling were evaluated in these interactions. Array analysis was used to compare transcript profiles in incompatible and compatible interactions of tomato roots 24 h after RKN infestation. The jai1 and def1 tomato mutant, altered in JA signaling, and tomato transgenic line NahG, altered in SA signaling, in the presence or absence of the RKN resistance gene Mi-1, were evaluated. The array analysis identified 1,497 and 750 genes differentially regulated in the incompatible and compatible interactions, respectively. Of the differentially regulated genes, 37% were specific to the incompatible interactions. NahG affected neither Mi-1 resistance nor basal defenses to RKNs. However, jai1 reduced tomato susceptibility to RKNs while not affecting Mi-1 resistance. In contrast, the def1 mutant did not affect RKN susceptibility. These results indicate that JA-dependent signaling does not play a role in Mi-1-mediated defense; however, an intact JA signaling pathway is required for tomato susceptibility to RKNs. In addition, low levels of SA might be sufficient for basal and Mi-1 resistance to RKNs.

  12. Jasmonic Acid, Abscisic Acid, and Salicylic Acid Are Involved in the Phytoalexin Responses of Rice to Fusarium fujikuroi, a High Gibberellin Producer Pathogen.

    PubMed

    Siciliano, Ilenia; Amaral Carneiro, Greice; Spadaro, Davide; Garibaldi, Angelo; Gullino, Maria Lodovica

    2015-09-23

    Fusarium fujikuroi, the causal agent of bakanae disease, is the main seedborne pathogen on rice. To understand the basis of rice resistance, a quantitative method to simultaneously detect phytohormones and phytoalexins was developed by using HPLC-MS/MS. With this method dynamic profiles and possible interactions of defense-related phytohormones and phytoalexins were investigated on two rice cultivars, inoculated or not with F. fujikuroi. In the resistant cultivar Selenio, the presence of pathogen induced high production of phytoalexins, mainly sakuranetin, and symptoms of bakanae were not observed. On the contrary, in the susceptible genotype Dorella, the pathogen induced the production of gibberellin and abscisic acid and inhibited jasmonic acid production, phytoalexins were very low, and bakanae symptoms were observed. The results suggested that a wide range of secondary metabolites are involved in plant defense against pathogens and phytoalexin synthesis could be an important factor for rice resistance against bakanae disease.

  13. Hexanoic acid is a resistance inducer that protects tomato plants against Pseudomonas syringae by priming the jasmonic acid and salicylic acid pathways.

    PubMed

    Scalschi, Loredana; Vicedo, Begonya; Camañes, Gemma; Fernandez-Crespo, Emma; Lapeña, Leonor; González-Bosch, Carmen; García-Agustín, Pilar

    2013-05-01

    Hexanoic acid-induced resistance (Hx-IR) is effective against several pathogens in tomato plants. Our study of the mechanisms implicated in Hx-IR against Pseudomonas syringae pv. tomato DC3000 suggests that hexanoic acid (Hx) treatment counteracts the negative effect of coronatine (COR) and jasmonyl-isoleucine (JA-Ile) on the salicylic acid (SA) pathway. In Hx-treated plants, an increase in the expression of jasmonic acid carboxyl methyltransferase (JMT) and the SA marker genes PR1 and PR5 indicates a boost in this signalling pathway at the expense of a decrease in JA-Ile. Moreover, Hx treatment potentiates 12-oxo-phytodienoic acid accumulation, which suggests that this molecule might play a role per se in Hx-IR. These results support a positive relationship between the SA and JA pathways in Hx-primed plants. Furthermore, one of the mechanisms of virulence mediated by COR is stomatal re-opening on infection with P. syringae. In this work, we observed that Hx seems to inhibit stomatal opening in planta in the presence of COR, which suggests that, on infection in tomato, this treatment suppresses effector action to prevent bacterial entry into the mesophyll.

  14. Sink limitation induces the expression of multiple soybean vegetative lipoxygenase mRNAs while the endogenous jasmonic acid level remains low.

    PubMed

    Bunker, T W; Koetje, D S; Stephenson, L C; Creelman, R A; Mullet, J E; Grimes, H D

    1995-08-01

    The response of individual members of the lipoxygenase multigene family in soybeans to sink deprivation was analyzed. RNase protection assays indicated that a novel vegetative lipoxygenase gene, vlxC, and three other vegetative lipoxygenase mRNAs accumulated in mature leaves in response to a variety of sink limitations. These data suggest that several members of the lipoxygenase multigene family are involved in assimilate partitioning. The possible involvement of jasmonic acid as a signaling molecule regulating assimilate partitioning into the vegetative storage proteins and lipoxygenases was directly assessed by determining the endogenous level of jasmonic acid in leaves from plants with their pods removed. There was no rise in the level of endogenous jasmonic acid coincident with the strong increase in both vlxC and vegetative storage protein VspB transcripts in response to sink limitation. Thus, expression of the vegetative lipoxygenases and vegetative storage proteins is not regulated by jasmonic acid in sink-limited leaves.

  15. Arabidopsis MYC Transcription Factors Are the Target of Hormonal Salicylic Acid/Jasmonic Acid Cross Talk in Response to Pieris brassicae Egg Extract1[OPEN

    PubMed Central

    Schmiesing, André; Gouhier-Darimont, Caroline

    2016-01-01

    Arabidopsis (Arabidopsis thaliana) plants recognize insect eggs and activate the salicylic acid (SA) pathway. As a consequence, expression of defense genes regulated by the jasmonic acid (JA) pathway is suppressed and larval performance is enhanced. Cross talk between defense signaling pathways is common in plant-pathogen interactions, but the molecular mechanism mediating this phenomenon is poorly understood. Here, we demonstrate that egg-induced SA/JA antagonism works independently of the APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor ORA59, which controls the ERF branch of the JA pathway. In addition, treatment with egg extract did not enhance expression or stability of JASMONATE ZIM-domain transcriptional repressors, and SA/JA cross talk did not involve JASMONATE ASSOCIATED MYC2-LIKEs, which are negative regulators of the JA pathway. Investigating the stability of MYC2, MYC3, and MYC4, three basic helix-loop-helix transcription factors that additively control jasmonate-related defense responses, we found that egg extract treatment strongly diminished MYC protein levels in an SA-dependent manner. Furthermore, we identified WRKY75 as a novel and essential factor controlling SA/JA cross talk. These data indicate that insect eggs target the MYC branch of the JA pathway and uncover an unexpected modulation of SA/JA antagonism depending on the biological context in which the SA pathway is activated. PMID:26884488

  16. Inhibitory effect of jasmonic acid and ethylene on epicotyl growth and bud induction in the maritime pine, Pinus pinaster Soland. in ait.

    PubMed

    Martin, Maria Teresa; Pedranzani, Hilda; García-Molinero, Patricia; Pando, Valentin; Sierra-de-Grado, Rosario

    2009-12-01

    Two independent parameters, epicotyl height (cm) and number of induced buds were studied on Pinus pinaster explants to analyse the effects of three phytohormones (6-benzylaminopurine, jasmonic acid, ethylene) which were combined or not in 11 different treatments. Epicotyle length diminished significantly in relation to the control medium (medium without exogen phytohormones) in presence of jasmonic acid, 6-benzylaminopurine or Ethephon (which is converted to ethylene in plants) in any of treatments. Concentrations of 100 microM of jasmonic acid and Ethephon had a greater inhibitory effect than the treatments with 10 microM. In addition to that, jasmonic acid was a stronger inhibitor than Ethephon in any of the tried combinations. There were no significant differences between the control treatment and the treatments with only 10 microM of jasmonic acid or Ethephon. However, 10 microM 6-benzylaminopurine induced bud formation. The different combinations of 6-benzylaminopurine with jasmonic acid and Ethephon showed that concentrations of 10 to 100 microM did not affect the number of induced buds. Jasmonic acid had an inhibitory effect which Ethephon only showed when combined with 100 microM of jasmonic acid and 10 microM of 6-benzylaminopurine. Three response groups were defined by cluster analysis: group 1 produced the greatest mean number of buds (4 to 5) and a mean epicotyl growth of 1 to 1.5 cm; group 2 produced 2 to 4 buds and a mean growth of 0.5 to 1.2 cm; group 3 produced only one bud and a mean epicotyl length of 1.2 to 2 cm.

  17. The DELLA Protein SLR1 Integrates and Amplifies Salicylic Acid- and Jasmonic Acid-Dependent Innate Immunity in Rice1

    PubMed Central

    De Vleesschauwer, David; Seifi, Hamed Soren; Haeck, Ashley; Huu, Son Nguyen; Demeestere, Kristof

    2016-01-01

    Gibberellins are a class of tetracyclic plant hormones that are well known to promote plant growth by inducing the degradation of a class of nuclear growth-repressing proteins, called DELLAs. In recent years, GA and DELLAs are also increasingly implicated in plant responses to pathogen attack, although our understanding of the underlying mechanisms is still limited, especially in monocotyledonous crop plants. Aiming to further decipher the molecular underpinnings of GA- and DELLA-modulated plant immunity, we studied the dynamics and impact of GA and DELLA during infection of the model crop rice (Oryza sativa) with four different pathogens exhibiting distinct lifestyles and infection strategies. Opposite to previous findings in Arabidopsis (Arabidopsis thaliana), our findings reveal a prominent role of the DELLA protein Slender Rice1 (SLR1) in the resistance toward (hemi)biotrophic but not necrotrophic rice pathogens. Moreover, contrary to the differential effect of DELLA on the archetypal defense hormones salicylic acid (SA) and jasmonic acid (JA) in Arabidopsis, we demonstrate that the resistance-promoting effect of SLR1 is due at least in part to its ability to boost both SA- and JA-mediated rice defenses. In a reciprocal manner, we found JA and SA treatment to interfere with GA metabolism and stabilize SLR1. Together, these findings favor a model whereby SLR1 acts as a positive regulator of hemibiotroph resistance in rice by integrating and amplifying SA- and JA-dependent defense signaling. Our results highlight the differences in hormone defense networking between rice and Arabidopsis and underscore the importance of GA and DELLA in molding disease outcomes. PMID:26829979

  18. Short- and long-term changes in sugarbeet (Beta vulgaris L.) gene expression due to postharvest jasmonic acid treatment - Data.

    PubMed

    de Oliveira, Lucilene Silva; Fugate, Karen Klotz; Ferrareze, Jocleita Perruzo; Bolton, Melvin D; Deckard, Edward L; Finger, Fernando L

    2017-04-01

    Jasmonic acid is a natural plant hormone that induces native defense responses in plants. Sugarbeet (Beta vulgaris L.) root unigenes that were differentially expressed 2 and 60 days after a postharvest jasmonic acid treatment are presented. Data include changes in unigene expression relative to water-treated controls, unigene annotations against nonredundant (Nr), Swiss-Prot, Clusters of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) protein databases, and unigene annotations with Gene Ontology (GO) terms. Putative defense unigenes are compiled and annotated against the sugarbeet genome. Differential gene expression data were generated by RNA sequencing. Interpretation of the data is available in the research article, "Jasmonic acid causes short- and long-term alterations to the transcriptome and the expression of defense genes in sugarbeet roots" (K.K. Fugate, L.S. Oliveira, J.P. Ferrareze, M.D. Bolton, E.L. Deckard, F.L. Finger, 2017) [1]. Public dissemination of this dataset will allow further analyses of the data.

  19. Rhizobacteria-induced priming in Arabidopsis is dependent on ethylene, jasmonic acid, and NPR1.

    PubMed

    Ahn, Il-Pyung; Lee, Sang-Woo; Suh, Seok-Cheol

    2007-07-01

    A nonpathogenic rhizobacterium, Pseudomonas putida LSW17S, elicited systemic protection against Fusarium wilt and pith necrosis caused by Fusarium oxysporum f. sp. lycopersici and P. corrugata in tomato (Lycopersicon esculentum L.). LSW17S also confers disease resistance against P. syringae pv. tomato DC3000 (DC3000) on Arabidopsis ecotype Col-0. To investigate mechanisms underlying disease protection, expression patterns of defense-related genes PR1, PR2, PR5, and PDF1.2 and cellular defense responses such as hydrogen peroxide accumulation and callose deposition were investigated. LSW17S treatment exhibited the typical phenomena of priming. Strong and faster transcription of defense-related genes was induced and hydrogen peroxide or callose were accumulated in Arabidopsis treated with LSW17S and infected with DC3000. In contrast, individual actions of LSW17S and DC3000 did not elicit rapid molecular and cellular defense responses. Priming by LSW17S was translocated systemically and retained for more than 10 days. Treatment with LSW17S reduced pathogen proliferation in Arabidopsis ecotype Col-0 expressing bacterial NahG; however, npr1, etr1, and jar1 mutations impaired inhibition of pathogen growth. Cellular and molecular priming responses support these results. In sum, LSW17S primes Arabidopsis for NPR1-, ethylene-, and jasmonic acid-dependent disease resistance, and efficient molecular and cellular defense responses.

  20. Costs of jasmonic acid induced defense in aboveground and belowground parts of corn (Zea mays L.).

    PubMed

    Feng, Yuanjiao; Wang, Jianwu; Luo, Shiming; Fan, Huizhi; Jin, Qiong

    2012-08-01

    Costs of jasmonic acid (JA) induced plant defense have gained increasing attention. In this study, JA was applied continuously to the aboveground (AG) or belowground (BG) parts, or AG plus BG parts of corn (Zea mays L.) to investigate whether JA exposure in one part of the plant would affect defense responses in another part, and whether or not JA induced defense would incur allocation costs. The results indicated that continuous JA application to AG parts systemically affected the quantities of defense chemicals in the roots, and vice versa. Quantities of DIMBOA and total amounts of phenolic compounds in leaves or roots generally increased 2 or 4 wk after the JA treatment to different plant parts. In the first 2 wk after application, the increase of defense chemicals in leaves and roots was accompanied by a significant decrease of root length, root surface area, and root biomass. Four weeks after the JA application, however, no such costs for the increase of defense chemicals in leaves and roots were detected. Instead, shoot biomass and root biomass increased. The results suggest that JA as a defense signal can be transferred from AG parts to BG parts of corn, and vice versa. Costs for induced defense elicited by continuous JA application were found in the early 2 wk, while distinct benefits were observed later, i.e., 4 wk after JA treatment.

  1. Jasmonic acid-induced changes in Brassica oleracea affect oviposition preference of two specialist herbivores.

    PubMed

    Bruinsma, Maaike; Van Dam, Nicole M; Van Loon, Joop J A; Dicke, Marcel

    2007-04-01

    Jasmonic acid (JA) is a key hormone involved in plant defense responses. The effect of JA treatment of cabbage plants on their acceptability for oviposition by two species of cabbage white butterflies, Pieris rapae and P. brassicae, was investigated. Both butterfly species laid fewer eggs on leaves of JA-treated plants compared to control plants. We show that this is due to processes in the plant after JA treatment rather than an effect of JA itself. The oviposition preference for control plants is adaptive, as development time from larval hatch until pupation of P. rapae caterpillars was longer on JA-treated plants. Total glucosinolate content in leaf surface extracts was similar for control and treated plants; however, two of the five glucosinolates were present in lower amounts in leaf surface extracts of JA-treated plants. When the butterflies were offered a choice between the purified glucosinolate fraction isolated from leaf surface extracts of JA-treated plants and that from control plants, they did not discriminate. Changes in leaf surface glucosinolate profile, therefore, do not seem to explain the change in oviposition preference of the butterflies after JA treatment, suggesting that as yet unknown infochemicals are involved.

  2. Expression of Vitis amurensis NAC26 in Arabidopsis enhances drought tolerance by modulating jasmonic acid synthesis

    PubMed Central

    Fang, Linchuan; Su, Lingye; Sun, Xiaoming; Li, Xinbo; Sun, Mengxiang; Karungo, Sospeter Karanja; Fang, Shuang; Chu, Jinfang; Li, Shaohua; Xin, Haiping

    2016-01-01

    The growth and fruit quality of grapevines are widely affected by abnormal climatic conditions such as water deficits, but many of the precise mechanisms by which grapevines respond to drought stress are still largely unknown. Here, we report that VaNAC26, a member of the NAC transcription factor family, was upregulated dramatically during cold, drought and salinity treatments in Vitis amurensis, a cold and drought-hardy wild Vitis species. Heterologous overexpression of VaNAC26 enhanced drought and salt tolerance in transgenic Arabidopsis. Higher activities of antioxidant enzymes and lower concentrations of H2O2 and O2 − were found in VaNAC26-OE lines than in wild type plants under drought stress. These results indicated that scavenging by reactive oxygen species (ROS) was enhanced by VaNAC26 in transgenic lines. Microarray-based transcriptome analysis revealed that genes related to jasmonic acid (JA) synthesis and signaling were upregulated in VaNAC26-OE lines under both normal and drought conditions. VaNAC26 showed a specific binding ability on the NAC recognition sequence (NACRS) motif, which broadly exists in the promoter regions of upregulated genes in transgenic lines. Endogenous JA content significantly increased in the VaNAC26-OE lines 2 and 3. Our data suggest that VaNAC26 responds to abiotic stresses and may enhance drought tolerance by transcriptional regulation of JA synthesis in Arabidopsis. PMID:27162276

  3. The Pokeweed Leaf mRNA Transcriptome and Its Regulation by Jasmonic Acid.

    PubMed

    Neller, Kira C M; Klenov, Alexander; Hudak, Katalin A

    2016-01-01

    The American pokeweed plant, Phytolacca americana, is recognized for synthesizing pokeweed antiviral protein (PAP), a ribosome inactivating protein (RIP) that inhibits the replication of several plant and animal viruses. The plant is also a heavy metal accumulator with applications in soil remediation. However, little is known about pokeweed stress responses, as large-scale sequencing projects have not been performed for this species. Here, we sequenced the mRNA transcriptome of pokeweed in the presence and absence of jasmonic acid (JA), a hormone mediating plant defense. Trinity-based de novo assembly of mRNA from leaf tissue and BLASTx homology searches against public sequence databases resulted in the annotation of 59 096 transcripts. Differential expression analysis identified JA-responsive genes that may be involved in defense against pathogen infection and herbivory. We confirmed the existence of several PAP isoforms and cloned a potentially novel isoform of PAP. Expression analysis indicated that PAP isoforms are differentially responsive to JA, perhaps indicating specialized roles within the plant. Finally, we identified 52 305 natural antisense transcript pairs, four of which comprised PAP isoforms, suggesting a novel form of RIP gene regulation. This transcriptome-wide study of a Phytolaccaceae family member provides a source of new genes that may be involved in stress tolerance in this plant. The sequences generated in our study have been deposited in the SRA database under project # SRP069141.

  4. The Pokeweed Leaf mRNA Transcriptome and Its Regulation by Jasmonic Acid

    PubMed Central

    Neller, Kira C. M.; Klenov, Alexander; Hudak, Katalin A.

    2016-01-01

    The American pokeweed plant, Phytolacca americana, is recognized for synthesizing pokeweed antiviral protein (PAP), a ribosome inactivating protein (RIP) that inhibits the replication of several plant and animal viruses. The plant is also a heavy metal accumulator with applications in soil remediation. However, little is known about pokeweed stress responses, as large-scale sequencing projects have not been performed for this species. Here, we sequenced the mRNA transcriptome of pokeweed in the presence and absence of jasmonic acid (JA), a hormone mediating plant defense. Trinity-based de novo assembly of mRNA from leaf tissue and BLASTx homology searches against public sequence databases resulted in the annotation of 59 096 transcripts. Differential expression analysis identified JA-responsive genes that may be involved in defense against pathogen infection and herbivory. We confirmed the existence of several PAP isoforms and cloned a potentially novel isoform of PAP. Expression analysis indicated that PAP isoforms are differentially responsive to JA, perhaps indicating specialized roles within the plant. Finally, we identified 52 305 natural antisense transcript pairs, four of which comprised PAP isoforms, suggesting a novel form of RIP gene regulation. This transcriptome-wide study of a Phytolaccaceae family member provides a source of new genes that may be involved in stress tolerance in this plant. The sequences generated in our study have been deposited in the SRA database under project # SRP069141. PMID:27014307

  5. Responses of herbivore and predatory mites to tomato plants exposed to jasmonic acid seed treatment.

    PubMed

    Smart, Lesley E; Martin, Janet L; Limpalaër, Marlène; Bruce, Toby J A; Pickett, John A

    2013-10-01

    Jasmonic acid (JA) signalling can influence plant defense and the production of plant volatiles that mediate interactions with insects. Here, we tested whether a JA seed treatment could alter direct and indirect defenses. First, oviposition levels of herbivorous mites, Tetranychus urticae, on JA seed-treated and control tomato plants were compared. They were not significantly different on tomato cv. 'Moneymaker', however, there was a significant reduction in oviposition on treated plants in additional experiments with cv. 'Carousel'. Second, responses of predatory mites, Phytoseiulus persimilis, were assessed in a Y-tube olfactometer. Volatiles from JA seed-treated tomato cv. 'Moneymaker' plants were significantly more attractive than volatiles from control plants. Volatiles collected from plants were analysed by GC/MS, and samples from JA seed-treated plants contained more methyl salicylate and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT) than samples from control plants. Our results indicate that JA seed treatment can make tomato plants more attractive to predatory mites, but that direct effects on herbivorous mites are variable and cultivar dependent.

  6. Expression of Vitis amurensis NAC26 in Arabidopsis enhances drought tolerance by modulating jasmonic acid synthesis.

    PubMed

    Fang, Linchuan; Su, Lingye; Sun, Xiaoming; Li, Xinbo; Sun, Mengxiang; Karungo, Sospeter Karanja; Fang, Shuang; Chu, Jinfang; Li, Shaohua; Xin, Haiping

    2016-04-01

    The growth and fruit quality of grapevines are widely affected by abnormal climatic conditions such as water deficits, but many of the precise mechanisms by which grapevines respond to drought stress are still largely unknown. Here, we report that VaNAC26, a member of the NAC transcription factor family, was upregulated dramatically during cold, drought and salinity treatments in Vitis amurensis, a cold and drought-hardy wild Vitis species. Heterologous overexpression of VaNAC26 enhanced drought and salt tolerance in transgenic Arabidopsis. Higher activities of antioxidant enzymes and lower concentrations of H2O2 and O2 (-) were found in VaNAC26-OE lines than in wild type plants under drought stress. These results indicated that scavenging by reactive oxygen species (ROS) was enhanced by VaNAC26 in transgenic lines. Microarray-based transcriptome analysis revealed that genes related to jasmonic acid (JA) synthesis and signaling were upregulated in VaNAC26-OE lines under both normal and drought conditions. VaNAC26 showed a specific binding ability on the NAC recognition sequence (NACRS) motif, which broadly exists in the promoter regions of upregulated genes in transgenic lines. Endogenous JA content significantly increased in the VaNAC26-OE lines 2 and 3. Our data suggest that VaNAC26 responds to abiotic stresses and may enhance drought tolerance by transcriptional regulation of JA synthesis in Arabidopsis.

  7. Regulation of basal and oxidative stress-triggered jasmonic acid-related gene expression by glutathione.

    PubMed

    Han, Yi; Mhamdi, Amna; Chaouch, Sejir; Noctor, Graham

    2013-06-01

    Glutathione is a determinant of cellular redox state with roles in defence and detoxification. Emerging concepts suggest that this compound also has functions in cellular signalling. Here, we report evidence that glutathione plays potentially important roles in setting signalling strength through the jasmonic acid (JA) pathway. Firstly, we show that basal expression of JA-related genes is correlated with leaf glutathione content when the latter is manipulated either genetically or pharmacologically. Secondly, analyses of an oxidative stress signalling mutant, cat2, reveal that up-regulation of the JA pathway triggered by intracellular oxidation requires accompanying glutathione accumulation. Genetically blocking this accumulation in a cat2 cad2 line largely annuls H2 O2 -induced expression of JA-linked genes, and this effect can be rescued by exogenously supplying glutathione. While most attention on glutathione functions in biotic stress responses has been focused on the thiol-regulated protein NPR1, a comparison of JA-linked gene expression in cat2 cad2 and cat2 npr1 double mutants provides evidence that glutathione acts through other components to regulate the response of this pathway to oxidative stress. Our study provides new information implicating glutathione as a factor determining basal JA gene expression and suggests novel glutathione-dependent control points that regulate JA signalling in response to intracellular oxidation.

  8. Thiol-based Redox Proteins in Brassica napus Guard Cell Abscisic Acid and Methyl Jasmonate Signaling

    PubMed Central

    Zhu, Mengmeng; Zhu, Ning; Song, Wen-yuan; Harmon, Alice C.; Assmann, Sarah M.; Chen, Sixue

    2014-01-01

    SUMMARY Reversibly oxidized cysteine sulfhydryl groups serve as redox sensors or targets of redox sensing that are important in different physiological processes. Little is known, however, about redox sensitive proteins in guard cells and how they function in stomatal signaling. In this study, Brassica napus guard cell proteins altered by redox in response to abscisic acid (ABA) or methyl jasmonate (MeJA) were identified by complementary proteomics approaches, saturation differential in-gel electrophoresis (DIGE) and isotope-coded affinity tag (ICAT). In total, 65 and 118 potential redox responsive proteins were identified in ABA and MeJA treated guard cells, respectively. All the proteins contain at least one cysteine, and over half of them are predicted to form intra-molecular disulfide bonds. Most of the proteins fall into the functional groups of energy, stress and defense, and metabolism. Based on the peptide sequences identified by mass spectrometry, 30 proteins were common to ABA and MeJA treated samples. A total of 44 cysteines was mapped in all the identified proteins, and their levels of redox sensitivity were quantified. Two of the proteins, a SNRK2 kinase and an isopropylmalate dehydrogenase were confirmed to be redox regulated and involved in stomatal movement. This study creates an inventory of potential redox switches, and highlights a protein redox regulatory mechanism in guard cell ABA and MeJA signal transduction. PMID:24580573

  9. Induction of annexin by heavy metals and jasmonic acid in Zea mays.

    PubMed

    Zhou, Mei-Liang; Yang, Xiong-Bang; Zhang, Qian; Zhou, Ming; Zhao, En-Ze; Tang, Yi-Xiong; Zhu, Xue-Mei; Shao, Ji-Rong; Wu, Yan-Min

    2013-06-01

    Plant annexins are Ca(2+)- and phospholipid-binding proteins forming an evolutionary conserved multi-gene family. They are implicated in the regulation of plant growth, development, and stress responses. With the availability of the maize genome sequence information, we identified 12 members of the maize annexin genes. Analysis of protein sequence and gene structure of maize annexins led to their classification into five different orthologous groups. Expression analysis by RT-PCR revealed that these genes are responsive to heavy metals (Ni, Zn, and Cd). The maize annexin genes were also found to be regulated by Ustilago maydis and jasmonic acid. Additionally, the promoter of the maize annexin gene was analyzed for the presence of different stress-responsive cis-elements, such as ABRE, W-box, GCC-box, and G-box. RT-PCR and microarray data show that all 12 maize annexin genes present differential, organ-specific expression patterns in the maize developmental steps. These results indicate that maize annexin genes may play important roles in the adaptation of plants to various environmental stresses.

  10. Red/Far Red Light Controls Arbuscular Mycorrhizal Colonization via Jasmonic Acid and Strigolactone Signaling.

    PubMed

    Nagata, Maki; Yamamoto, Naoya; Shigeyama, Tamaki; Terasawa, Yohei; Anai, Toyoaki; Sakai, Tatsuya; Inada, Sayaka; Arima, Susumu; Hashiguchi, Masatsugu; Akashi, Ryo; Nakayama, Hideyuki; Ueno, Daisuke; Hirsch, Ann M; Suzuki, Akihiro

    2015-11-01

    Establishment of a nitrogen-fixing symbiosis between legumes and rhizobia not only requires sufficient photosynthate, but also the sensing of the ratio of red to far red (R/FR) light. Here, we show that R/FR light sensing also positively influences the arbuscular mycorrhizal (AM) symbiosis of a legume and a non-legume through jasmonic acid (JA) and strigolactone (SL) signaling. The level of AM colonization in high R/FR light-grown tomato and Lotus japonicus significantly increased compared with that determined for low R/FR light-grown plants. Transcripts for JA-related genes were also elevated under high R/FR conditions. The root exudates derived from high R/FR light-grown plants contained more (+)-5-deoxystrigol, an AM-fungal hyphal branching inducer, than those from low R/FR light-grown plants. In summary, high R/FR light changes not only the levels of JA and SL synthesis, but also the composition of plant root exudates released into the rhizosphere, in this way augmenting the AM symbiosis.

  11. Salicylic acid and methyl jasmonate improve chilling tolerance in cold-stored lemon fruit (Citrus limon).

    PubMed

    Siboza, Xolani Irvin; Bertling, Isa; Odindo, Alfred Oduor

    2014-11-15

    Chilling injury (CI) is associated with the degradation of membrane integrity which can be aligned to phenolic oxidation activated by polyphenol oxidase (PPO) and peroxidase (POD), enzymes responsible for tissue browning. Phenylalanine ammonia-lyase (PAL) is a further enzyme prominent in the phenolic metabolism that is involved in acclimation against chilling stress. It was hypothesized that treatment with methyl jasmonate (MJ) and salicylic acid (SA) may enhance chilling tolerance in lemon fruit by increasing the synthesis of total phenolics and PAL by activating the key enzyme regulating the shikimic acid pathway whilst inhibiting the activity of POD and PPO. Lemon fruit were treated with 10μM MJ, 2mM SA or 10μM MJ plus 2mM SA, waxed, stored at -0.5, 2 or 4.5°C for up to 28 days plus 7 days at 23°C. Membrane integrity was studied by investigating membrane permeability and the degree of membrane lipid peroxidation in lemon flavedo following cold storage. The 10μM MJ plus 2mM SA treatment was most effective in enhancing chilling tolerance of lemon fruit, significantly reducing chilling-induced membrane permeability and membrane lipid peroxidation of lemon flavedo tissue. This treatment also increased total phenolics and PAL activity in such tissue while inhibiting POD activity, the latter possibly contributing to the delay of CI manifestation. PPO activity was found to be a poor biochemical marker of CI. Treatment with 10μM MJ plus 2mM SA resulted in an alteration of the phenolic metabolism, enhancing chilling tolerance, possibly through increased production of total phenolics and the activation of PAL and inhibition of POD.

  12. Development of an ultrahigh-performance liquid chromatography-electrospray ionization-tandem mass spectrometry method for the simultaneous determination of salicylic acid, jasmonic acid, and abscisic acid in rose leaves.

    PubMed

    Bosco, Renato; Daeseleire, Els; Van Pamel, Els; Scariot, Valentina; Leus, Leen

    2014-07-09

    This paper describes a method to detect and quantitate the endogenous plant hormones (±)-2-cis-4-trans-abscisic acid, (-)-jasmonic acid, and salicylic acid by means of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in hybrid rose leaf matrices. Deuterium-labeled [(2)H6] (+)-2-cis-4-trans-abscisic acid, [(2)H6] (±)-jasmonic acid, and [(2)H4]-salicylic acid were used as internal standards. Rose samples (10 mg) were extracted with methanol/water/acetic acid (10:89:1) and subsequently purified on an Oasis MCX 1 cm(3) Vac SPE cartridge. Performance characteristics were validated according to Commission Decision 2002/657/EC. Recovery, repeatability, and within-laboratory reproducibility were acceptable for all phytohormones tested at three different concentrations. The decision limit and detection capability for (±)-2-cis-4-trans-abscisic acid, (-)-jasmonic acid, and salicylic acid were 0.0075 and 0.015 μg/g, 0.00015 and 0.00030 μg/g, and 0.0089 and 0.018 μg/g, respectively. Matrix effects (signal suppression or enhancement) appeared to be high for all substances considered, implying the need for quantitation based on matrix-matched calibration curves.

  13. Acyl-CoA N-acyltransferase influences fertility by regulating lipid metabolism and jasmonic acid biogenesis in cotton

    PubMed Central

    Fu, Wenfeng; Shen, Ying; Hao, Juan; Wu, Jianyong; Ke, Liping; Wu, Caiyun; Huang, Kai; Luo, Binglun; Xu, Mingfeng; Cheng, Xiaofei; Zhou, Xueping; Sun, Jie; Xing, Chaozhu; Sun, Yuqiang

    2015-01-01

    Cotton (Gossypium spp.) is an important economic crop and there is obvious heterosis in cotton, fertility has played an important role in this heterosis. However, the genes that exhibit critical roles in anther development and fertility are not well understood. Here, we report an acyl-CoA N-acyltransferase (EC2.3; GhACNAT) that plays a key role in anther development and fertility. Suppression of GhACNAT by virus-induced gene silencing in transgenic cotton (G. hirsutum L. cv. C312) resulted in indehiscent anthers that were full of pollen, diminished filaments and stamens, and plant sterility. We found GhACNAT was involved in lipid metabolism and jasmonic acid (JA) biosynthesis. The genes differentially expressed in GhACNAT-silenced plants and C312 were mainly involved in catalytic activity and transcription regulator activity in lipid metabolism. In GhACNAT-silenced plants, the expression levels of genes involved in lipid metabolism and jasmonic acid biosynthesis were significantly changed, the amount of JA in leaves and reproductive organs was significantly decreased compared with the amounts in C312. Treatments with exogenous methyl jasmonate rescued anther dehiscence and pollen release in GhACNAT-silenced plants and caused self-fertility. The GhACNAT gene may play an important role in controlling cotton fertility by regulating the pathways of lipid synthesis and JA biogenesis. PMID:26134787

  14. Jasmonic and salicylic acids enhanced phytochemical production and biological activities in cell suspension cultures of spine gourd (Momordica dioica Roxb).

    PubMed

    Chung, Ill-Min; Rekha, Kaliyaperumal; Rajakumar, Govindasamy; Thiruvengadam, Muthu

    2017-03-01

    In vitro cell suspension culture was established for the production of commercially valuable phytochemicals in Momordica dioica. The influence of elicitors in jasmonic acid (JA) and salicylic acid (SA) increased their effect on phytochemical production and biomass accumulation in M. dioica. The results indicate that compared with non-elicited cultures, JA- and SA-elicited cell suspension cultures had significantly enhanced phenolic, flavonoid, and carotenoid production, as well as antioxidant, antimicrobial, and antiproliferative activities. Furthermore, elicited cultures produced 22 phenolic compounds, such as flavonols, hydroxycinnamic acids, and hydroxybenzoic acids. Greater biomass production, phytochemical accumulation, and biological activity occurred in JA- than in SA-elicited cell cultures. This study is the first to successfully establish M. dioica cell suspension cultures for the production of phenolic compounds and carotenoids, as well as for biomass accumulation.

  15. Herbivore induction of jasmonic acid and chemical defences reduce photosynthesis in Nicotiana attenuata.

    PubMed

    Nabity, Paul D; Zavala, Jorge A; DeLucia, Evan H

    2013-01-01

    Herbivory initiates a shift in plant metabolism from growth to defence that may reduce fitness in the absence of further herbivory. However, the defence-induced changes in carbon assimilation that precede this reallocation in resources remain largely undetermined. This study characterized the response of photosynthesis to herbivore induction of jasmonic acid (JA)-related defences in Nicotiana attenuata to increase understanding of these mechanisms. It was hypothesized that JA-induced defences would immediately reduce the component processes of photosynthesis upon attack and was predicted that wild-type plants would suffer greater reductions in photosynthesis than plants lacking JA-induced defences. Gas exchange, chlorophyll fluorescence, and thermal spatial patterns were measured together with the production of defence-related metabolites after attack and through recovery. Herbivore damage immediately reduced electron transport and gas exchange in wild-type plants, and gas exchange remained suppressed for several days after attack. The sustained reductions in gas exchange occurred concurrently with increased defence metabolites in wild-type plants, whereas plants lacking JA-induced defences suffered minimal suppression in photosynthesis and no increase in defence metabolite production. This suppression in photosynthesis occurred only after sustained defence signalling and defence chemical mobilization, whereas a short bout of feeding damage only transiently altered components of photosynthesis. It was identified that lipoxygenase signalling interacted with photosynthetic electron transport and that the resulting JA-related metabolites reduced photosynthesis. These data represent a metabolic cost to mounting a chemical defence against herbivory and link defence-signalling networks to the differential effects of herbivory on photosynthesis in remaining leaf tissues in a time-dependent manner.

  16. Exogenous jasmonic acid can enhance tolerance of wheat seedlings to salt stress.

    PubMed

    Qiu, ZongBo; Guo, JunLi; Zhu, AiJing; Zhang, Liang; Zhang, ManMan

    2014-06-01

    Jasmonic acid (JA) is regarded as endogenous regulator that plays an important role in regulating stress responses, plant growth and development. To investigate the physiological mechanisms of salt stress mitigated by exogenous JA, foliar application of 2mM JA was done to wheat seedlings for 3days and then they were subjected to 150mM NaCl. Our results showed that 150mM NaCl treatment significantly decreased plant height, root length, shoot dry weight, root dry weight, the concentration of glutathione (GSH), chlorophyll b (Chl b) and carotenoid (Car), the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), enhanced the concentration of malondialdehyde (MDA), hydrogen peroxide (H2O2) and the rate of superoxide radical (O2•-) generation in the wheat seedlings when compared with the control. However, treatments with exogenous JA for 3 days significantly enhanced salt stress tolerance in wheat seedlings by decreasing the concentration of MDA and H2O2, the production rate of O2•- and increasing the transcript levels and activities of SOD, POD, CAT and APX and the contents of GSH, Chl b and Car, which, in turn, enhanced the growth of salt stressed seedlings. These results suggested that JA could effectively protect wheat seedlings from salt stress damage by enhancing activities of antioxidant enzymes and the concentration of antioxidative compounds to quench the excessive reactive oxygen species caused by salt stress and presented a practical implication for wheat cultivation in salt-affected soils.

  17. Leucine aminopeptidase regulates defense and wound signaling in tomato downstream of jasmonic acid.

    PubMed

    Fowler, Jonathan H; Narváez-Vásquez, Javier; Aromdee, Dale N; Pautot, Véronique; Holzer, Frances M; Walling, Linda L

    2009-04-01

    Leucine aminopeptidase A (LapA) is a late wound-response gene of tomato (Solanum lycopersicum). To elucidate the role of LapA, transgenic plants that overexpressed or abolished LapA gene expression were used. The early wound-response gene RNA levels were similar in wild-type and Lap-silenced (LapA-SI), -antisense (LapA-AS), and -overexpressing (LapA-OX) plants. By contrast, late wound-response gene RNA levels and protection against Manduca sexta damage were influenced by LapA RNA and protein levels. While LapA-OX plants had elevated levels of LapA RNAs and protein, ectopic expression of LapA was not sufficient to induce Pin (Ser proteinase inhibitor) or PPO (polyphenol oxidase) transcripts in nonwounded leaves. M. sexta larvae damaged less foliage and displayed delays in growth and development when feeding on LapA-OX plants. By contrast, LapA-SI and LapA-AS lines had lower levels of Pin and PPO RNAs than wild-type controls. Furthermore, larvae consumed more foliage and attained larger masses when feeding on LapA-SI plants. Jasmonic acid (JA) did not complement the wound-signaling phenotype of LapA-SI plants. Based on root elongation in the presence of JA, JA perception appeared to be intact in LapA-SI lines. Collectively, these data suggested that LAP-A has a role in modulating essential defenses against herbivores by promoting late wound responses and acting downstream of JA biosynthesis and perception.

  18. The Tryptophan Conjugates of Jasmonic and Indole-3-Acetic Acids Are Endogenous Auxin Inhibitors1[W][OA

    PubMed Central

    Staswick, Paul E.

    2009-01-01

    Most conjugates of plant hormones are inactive, and some function to reduce the active hormone pool. This study characterized the activity of the tryptophan (Trp) conjugate of jasmonic acid (JA-Trp) in Arabidopsis (Arabidopsis thaliana). Unexpectedly, JA-Trp caused agravitropic root growth in seedlings, unlike JA or nine other JA-amino acid conjugates. The response was dose dependent from 1 to100 μm, was independent of the COI1 jasmonate signaling locus, and unlike the jasmonate signal JA-isoleucine, JA-Trp minimally inhibited root growth. The Trp conjugate with indole-3-acetic acid (IAA-Trp) produced a similar response, while Trp alone and conjugates with benzoic and cinnamic acids did not. JA-Trp and IAA-Trp at 25 μm nearly eliminated seedling root inhibition caused by 2 μm IAA. The TIR1 auxin receptor is required for activity because roots of tir1-1 grew only approximately 60% of wild-type length on IAA plus JA-Trp, even though tir1-1 is auxin resistant. However, neither JA-Trp nor IAA-Trp interfered with IAA-dependent interaction between TIR1 and Aux/IAA7 in cell-free assays. Trp conjugates inhibited IAA-stimulated lateral root production and DR5-β-glucuronidase gene expression. JA-deficient mutants were hypersensitive to IAA and a Trp-overaccumulating mutant was less sensitive, suggesting endogenous conjugates affect auxin sensitivity. Conjugates were present at 5.8 pmol g−1 fresh weight or less in roots, seedlings, leaves, and flowers, and the values increased approximately 10-fold in roots incubated in 25 μm Trp and IAA or JA at 2 μm. These results show that JA-Trp and IAA-Trp constitute a previously unrecognized mechanism to regulate auxin action. PMID:19458116

  19. Circadian changes in endogenous concentrations of indole-3-acetic acid, melatonin, serotonin, abscisic acid and jasmonic acid in Characeae (Chara australis Brown)

    PubMed Central

    Beilby, Mary J; Turi, Christina E; Baker, Teesha C; Tymm, Fiona JM; Murch, Susan J

    2015-01-01

    Giant-celled Characeae (Chara australis Brown), grown for 4 months on 12/12 hr day/night cycle and summer/autumn temperatures, exhibited distinct concentration maxima in auxin (indole-3-acetic acid; IAA), melatonin and serotonin about 4 hr after subjective daybreak. These concentration peaks persisted after 3 day pretreatment in continuous darkness: confirming a circadian rhythm, rather than a response to “light on.” The plants pretreated for 3 d in continuous light exhibited several large IAA concentration maxima throughout the 24 hr. The melatonin and serotonin concentrations decreased and were less synchronized with IAA. Chara plants grown on 9/15 hr day/night cycle for 4 months and winter/spring temperatures contained much smaller concentrations of IAA, melatonin and serotonin. The IAA concentration maxima were observed in subjective dark phase. Serotonin concentration peaks were weakly correlated with those of IAA. Melatonin concentration was low and mostly independent of circadian cycle. The “dark” IAA concentration peaks persisted in plants treated for 3 d in the dark. The plants pretreated for 3 d in the light again developed more IAA concentration peaks. In this case the concentration maxima in melatonin and serotonin became more synchronous with those in IAA. The abscisic acid (ABA) and jasmonic acid (JA) concentrations were also measured in plants on winter regime. The ABA concentration did not exhibit circadian pattern, while JA concentration peaks were out of phase with those of IAA. The data are discussed in terms of crosstalk between metabolic pathways. PMID:26382914

  20. Jasmonic Acid and Its Precursor 12-Oxophytodienoic Acid Control Different Aspects of Constitutive and Induced Herbivore Defenses in Tomato1[W][OPEN

    PubMed Central

    Bosch, Marko; Wright, Louwrance P.; Gershenzon, Jonathan; Wasternack, Claus; Hause, Bettina; Schaller, Andreas; Stintzi, Annick

    2014-01-01

    The jasmonate family of growth regulators includes the isoleucine (Ile) conjugate of jasmonic acid (JA-Ile) and its biosynthetic precursor 12-oxophytodienoic acid (OPDA) as signaling molecules. To assess the relative contribution of JA/JA-Ile and OPDA to insect resistance in tomato (Solanum lycopersicum), we silenced the expression of OPDA reductase3 (OPR3) by RNA interference (RNAi). Consistent with a block in the biosynthetic pathway downstream of OPDA, OPR3-RNAi plants contained wild-type levels of OPDA but failed to accumulate JA or JA-Ile after wounding. JA/JA-Ile deficiency in OPR3-RNAi plants resulted in reduced trichome formation and impaired monoterpene and sesquiterpene production. The loss of these JA/JA-Ile -dependent defense traits rendered them more attractive to the specialist herbivore Manduca sexta with respect to feeding and oviposition. Oviposition preference resulted from reduced levels of repellant monoterpenes and sesquiterpenes. Feeding preference, on the other hand, was caused by increased production of cis-3-hexenal acting as a feeding stimulant for M. sexta larvae in OPR3-RNAi plants. Despite impaired constitutive defenses and increased palatability of OPR3-RNAi leaves, larval development was indistinguishable on OPR3-RNAi and wild-type plants, and was much delayed compared with development on the jasmonic acid-insensitive1 (jai1) mutant. Apparently, signaling through JAI1, the tomato ortholog of the ubiquitin ligase CORONATINE INSENSITIVE1 in Arabidopsis (Arabidopsis thaliana), is required for defense, whereas the conversion of OPDA to JA/JA-Ile is not. Comparing the signaling activities of OPDA and JA/JA-Ile, we found that OPDA can substitute for JA/JA-Ile in the local induction of defense gene expression, but the production of JA/JA-Ile is required for a systemic response. PMID:25073705

  1. The maize death acids, 10-oxo-11-phytoenoic acid and derivatives, demonstrate specificity in jasmonate-related signaling and defense

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant cellular damage promotes the interaction of lipoxygenases (LOX) with free fatty acids to yield 9- and 13-hydroperoxides which are further metabolized into diverse oxylipins. The enzymatic action of 13-LOX on linolenic acid enables production of 12-oxo-phytodienoic acid (12-OPDA) and its downst...

  2. Jasmonic acid-isoleucine formation in grapevine (Vitis vinifera L.) by two enzymes with distinct transcription profiles.

    PubMed

    Böttcher, Christine; Burbidge, Crista A; di Rienzo, Valentina; Boss, Paul K; Davies, Christopher

    2015-07-01

    The plant hormone jasmonic acid (JA) is essential for stress responses and the formation of reproductive organs, but its role in fruit development and ripening is unclear. Conjugation of JA to isoleucine is a crucial step in the JA signaling pathway since only JA-Ile is recognized by the jasmonate receptor. The conjugation reaction is catalyzed by JA-amido synthetases, belonging to the family of Gretchen Hagen3 (GH3) proteins. Here, in vitro studies of two grapevine (Vitis vinifera L. cv Shiraz) GH3 enzymes, VvGH3-7 and VvGH3-9, demonstrated JA-conjugating activities with an overlapping range of amino acid substrates, including isoleucine. Expression studies of the corresponding genes in grape berries combined with JA and JA-Ile measurements suggested a primary role for JA signaling in fruit set and cell division and did not support an involvement of JA in the ripening process. In response to methyl JA (MeJA) treatment, and in wounded and unwounded (distal) leaves, VvGH3-9 transcripts accumulated, indicating a participation in the JA response. In contrast, VvGH3-7 was unresponsive to MeJA and local wounding, demonstrating a differential transcriptional regulation of VvGH3-7 and VvGH3-9. The transient induction of VvGH3-7 in unwounded, distal leaves was suggestive of the involvement of an unknown mobile wound signal.

  3. Root jasmonic acid synthesis and perception regulate folivore-induced shoot metabolites and increase Nicotiana attenuata resistance.

    PubMed

    Fragoso, Variluska; Rothe, Eva; Baldwin, Ian T; Kim, Sang-Gyu

    2014-06-01

    While jasmonic acid (JA) signaling is widely accepted as mediating plant resistance to herbivores, and the importance of the roots in plant defenses is recently being recognized, the role of root JA in the defense of above-ground parts remains unstudied. To restrict JA impairment to the roots, we micrografted wildtype Nicotiana attenuata shoots to the roots of transgenic plants impaired in JA signaling and evaluated ecologically relevant traits in the glasshouse and in nature. Root JA synthesis and perception are involved in regulating nicotine production in roots. Strikingly, systemic root JA regulated local leaf JA and abscisic acid (ABA) concentrations, which were associated with differences in nicotine transport from roots to leaves via the transpiration stream. Root JA signaling also regulated the accumulation of other shoot metabolites; together these account for differences in resistance against a generalist, Spodoptera littoralis, and a specialist herbivore, Manduca sexta. In N. attenuata's native habitat, silencing root JA synthesis increased the shoot damage inflicted by Empoasca leafhoppers, which are able to select natural jasmonate mutants. Silencing JA perception in roots also increased damage by Tupiocoris notatus. We conclude that attack from above-ground herbivores recruits root JA signaling to launch the full complement of plant defense responses.

  4. Simultaneous induction of jasmonic acid and disease-responsive genes signifies tolerance of American elm to Dutch elm disease

    PubMed Central

    Sherif , S. M.; Shukla, M. R.; Murch, S. J.; Bernier, L.; Saxena, P. K.

    2016-01-01

    Dutch elm disease (DED), caused by three fungal species in the genus Ophiostoma, is the most devastating disease of both native European and North American elm trees. Although many tolerant cultivars have been identified and released, the tolerance mechanisms are not well understood and true resistance has not yet been achieved. Here we show that the expression of disease-responsive genes in reactions leading to tolerance or susceptibility is significantly differentiated within the first 144 hours post-inoculation (hpi). Analysis of the levels of endogenous plant defense molecules such as jasmonic acid (JA) and salicylic acid (SA) in tolerant and susceptible American elm saplings suggested SA and methyl-jasmonate as potential defense response elicitors, which was further confirmed by field observations. However, the tolerant phenotype can be best characterized by a concurrent induction of JA and disease-responsive genes at 96 hpi. Molecular investigations indicated that the expression of fungal genes (i.e. cerato ulmin) was also modulated by endogenous SA and JA and this response was unique among aggressive and non-aggressive fungal strains. The present study not only provides better understanding of tolerance mechanisms to DED, but also represents a first, verified template for examining simultaneous transcriptomic changes during American elm-fungus interactions. PMID:26902398

  5. Jasmonic acid influences mycorrhizal colonization in tomato plants by modifying the expression of genes involved in carbohydrate partitioning.

    PubMed

    Tejeda-Sartorius, Miriam; Martínez de la Vega, Octavio; Délano-Frier, John Paul

    2008-06-01

    The role of jasmonic acid (JA) on mycorrhizal colonization by Glomus fasciculatum in tomato plants was examined using mutant plants overexpressing prosystemin (PS) or affected in the synthesis of JA (suppressor of prosystemin-mediated responses 2, spr2). The degree of mycorrhizal colonization was determined by measuring frequency (F%) and intensity (M%) of colonization and arbuscule abundance (A%). Gene expression and biochemical analyses were also performed in roots to detect changes in carbon (C) partitioning. Colonization was similar in mycorrhizal PS and wild-type roots, except for a higher A% in the former. Conversely, colonization was severely reduced in roots of spr2 mutants. No association was found between levels of expression of genes coding for systemic wound responsive proteins (or SWRPs) and other defense-related proteins in roots and mycorrhization levels in these plants. On the other hand, the degree of mycorrhizal colonization correlated with changes in the transcriptional regulation of a number of genes involved in sucrose hydrolysis and transport, cell wall invertase activity and mycorrhizal-specific fatty acid content in roots. The results obtained suggest that one of the mechanisms by which JA might operate to modulate the mycorrhization process could be through its influence on the regulation of C partitioning in the plant. The significant colonization increase observed in mycorrhizal spr2 plants supplied with exogenous methyl jasmonate supports its role as a positive regulator of the symbiosis.

  6. Jasmonic acid distribution and action in plants: regulation during development and response to biotic and abiotic stress.

    PubMed

    Creelman, R A; Mullet, J E

    1995-05-09

    Jasmonic acid (JA) is a naturally occurring growth regulator found in higher plants. Several physiological roles have been described for this compound (or a related compound, methyl jasmonate) during plant development and in response to biotic and abiotic stress. To accurately determine JA levels in plant tissue, we have synthesized JA containing 13C for use as an internal standard with an isotopic composition of [225]:[224] 0.98:0.02 compared with [225]:[224] 0.15:0.85 for natural material. GC analysis (flame ionization detection and MS) indicate that the internal standard is composed of 92% 2-(+/-)-[13C]JA and 8% 2-(+/-)-7-iso-[13C]JA. In soybean plants, JA levels were highest in young leaves, flowers, and fruit (highest in the pericarp). In soybean seeds and seedlings, JA levels were highest in the youngest organs including the hypocotyl hook, plumule, and 12-h axis. In soybean leaves that had been dehydrated to cause a 15% decrease in fresh weight, JA levels increased approximately 5-fold within 2 h and declined to approximately control levels by 4 h. In contrast, a lag time of 1-2 h occurred before abscisic acid accumulation reached a maximum. These results will be discussed in the context of multiple pathways for JA biosynthesis and the role of JA in plant development and responses to environmental signals.

  7. Ozone sensitivity in hybrid poplar correlates with insensitivity to both salicylic acid and jasmonic acid. The role of programmed cell death in lesion formation.

    PubMed

    Koch, J R; Creelman, R A; Eshita, S M; Seskar, M; Mullet, J E; Davis, K R

    2000-06-01

    Our earlier studies demonstrated that the ozone-sensitive hybrid poplar clone NE-388 displays an attenuated level of ozone-, wound-, and phytopathogen-induced defense gene expression. To determine if this reduced gene activation involves signal transduction pathways dependent on salicylic acid (SA) and/or jasmonic acid (JA), we compared the responses of NE-388 and an ozone-tolerant clone, NE-245, to these signal molecules. JA levels increased in both clones in response to ozone, but only minimal increases in SA levels were measured for either clone. Treatment with SA and methyl jasmonate induced defense gene expression only in NE-245, indicating that NE-388 is insensitive to these signal molecules. DNA fragmentation, an indicator of programmed cell death (PCD), was detected in NE-245 treated with either ozone or an avirulent phytopathogen, but was not detected in NE-388. We conclude that these clones undergo two distinct mechanisms of ozone-induced lesion formation. In NE-388, lesions appear to be due to toxic cell death resulting from a limited ability to perceive and subsequently activate SA- and/or JA-mediated antioxidant defense responses. In NE-245, SA-dependent PCD precedes lesion formation via a process related to the PCD pathway activated by phytopathogenic bacteria. These results support the hypothesis that ozone triggers a hypersensitive response.

  8. Cell line selection combined with jasmonic acid elicitation enhance camptothecin production in cell suspension cultures of Ophiorrhiza mungos L.

    PubMed

    Deepthi, S; Satheeshkumar, K

    2017-01-01

    Ophiorrhiza mungos is a herbaceous medicinal plant which contains a quinoline alkaloid, camptothecin (CPT), an anticancer compound. A high-yielding cell line, O. mungos cell line-3 (OMC3) was selected from cell suspension cultures of O. mungos using cell aggregate cloning method and established cell suspension culture. OMC3 cell suspension produced significantly high biomass (9.25 ± 1.3 g/flask fresh weight (FW)) and CPT yield (0.095 ± 0.002 mg g(-1) dry weight (DW)) compared with the original cell suspension. Inoculum size of OMC3 cell suspension culture was optimised as 14 g L(-1). Media optimisation has shown that 5 % (w/v) sucrose and an increased ammonium/nitrate concentration of 40/20 mM favoured CPT production, whereas 3 % (w/v) sucrose, an ammonium/nitrate concentration of 20/40 mM and 1.25 mM of phosphate favoured biomass accumulation. Jasmonic acid, chitin and salicylic acid was used to elicit CPT production in the original cell suspension culture and achieved significantly high CPT production with jasmonic acid (JA) elicitation. Further, OMC3 cell suspension culture was elicited with JA (50 μM) and obtained 1.12 ± 0.08 mg g(-1) DW CPT and 9.52 ± 1.4 g/flask FW (190.4 g L(-1) FW). The combination of cell line selection and elicitation has produced 18.66-fold increases in CPT production together with significantly high biomass yield. The study is helpful in the scale-up studies of O. mungos cell suspension culture in suitable bioreactor systems for the production of CPT.

  9. The crosstalk between Target of Rapamycin (TOR) and Jasmonic Acid (JA) signaling existing in Arabidopsis and cotton

    PubMed Central

    Song, Yun; Zhao, Ge; Zhang, Xueyan; Li, Linxuan; Xiong, Fangjie; Zhuo, Fengping; Zhang, Chaojun; Yang, Zuoren; Datla, Raju; Ren, Maozhi; Li, Fuguang

    2017-01-01

    Target of rapamycin (TOR) acts as an important regulator of cell growth, development and stress responses in most examined diploid eukaryotes. However, little is known about TOR in tetraploid species such as cotton. Here, we show that TORC1-S6K-RPS6, the major signaling components, are conserved and further expanded in cotton genome. Though the cotton seedlings are insensitive to rapamycin, AZD8055, the second-generation inhibitor of TOR, can significantly suppress the growth in cotton. Global transcriptome analysis revealed that genes associated with jasmonic acid (JA) biosynthesis and transduction were significantly altered in AZD8055 treated cotton seedlings, suggesting the potential crosstalk between TOR and JA signaling. Pharmacological and genetic approaches have been employed to get further insights into the molecular mechanism of the crosstalk between TOR and JA. Combination of AZD8055 with methyl jasmonate can synergistically inhibit cotton growth, and additionally JA levels were significantly increased when cotton seedlings were subjected to AZD8055. JA biosynthetic and signaling mutants including jar1, coi1-2 and myc2-2 displayed TOR inhibitor-resistant phenotypes, whereas COI1 overexpression transgenic lines and jaz10 exhibited sensitivity to AZD8055. Consistently, cotton JAZ can partially rescue TOR-suppressed phenotypes in Arabidopsis. These evidences revealed that the crosstalk between TOR and JA pathway operates in cotton and Arabidopsis. PMID:28374843

  10. Ecological trade-offs between jasmonic acid-dependent direct and indirect plant defences in tritrophic interactions

    PubMed Central

    Wei, Jianing; Wang, Lizhong; Zhao, Jiuhai; Li, Chuanyou; Ge, Feng; Kang, Le

    2011-01-01

    Recent studies on plants genetically modified in jasmonic acid (JA) signalling support the hypothesis that the jasmonate family of oxylipins plays an important role in mediating direct and indirect plant defences. However, the interaction of two modes of defence in tritrophic systems is largely unknown. In this study, we examined the preference and performance of a herbivorous leafminer (Liriomyza huidobrensis) and its parasitic wasp (Opius dissitus) on three tomato genotypes: a wild-type (WT) plant, a JA biosynthesis (spr2) mutant, and a JA-overexpression 35S::prosys plant. Their proteinase inhibitor production and volatile emission were used as direct and indirect defence factors to evaluate the responses of leafminers and parasitoids. Here, we show that although spr2 mutant plants are compromised in direct defence against the larval leafminers and in attracting parasitoids, they are less attractive to adult flies compared with WT plants. Moreover, in comparison to other genotypes, the 35S::prosys plant displays greater direct and constitutive indirect defences, but reduced success of parasitism by parasitoids. Taken together, these results suggest that there are distinguished ecological trade-offs between JA-dependent direct and indirect defences in genetically modified plants whose fitness should be assessed in tritrophic systems and under natural conditions. PMID:21039561

  11. Ecological trade-offs between jasmonic acid-dependent direct and indirect plant defences in tritrophic interactions.

    PubMed

    Wei, Jianing; Wang, Lizhong; Zhao, Jiuhai; Li, Chuanyou; Ge, Feng; Kang, Le

    2011-01-01

    Recent studies on plants genetically modified in jasmonic acid (JA) signalling support the hypothesis that the jasmonate family of oxylipins plays an important role in mediating direct and indirect plant defences. However, the interaction of two modes of defence in tritrophic systems is largely unknown. In this study, we examined the preference and performance of a herbivorous leafminer (Liriomyza huidobrensis) and its parasitic wasp (Opius dissitus) on three tomato genotypes: a wild-type (WT) plant, a JA biosynthesis (spr2) mutant, and a JA-overexpression 35S::prosys plant. Their proteinase inhibitor production and volatile emission were used as direct and indirect defence factors to evaluate the responses of leafminers and parasitoids. Here, we show that although spr2 mutant plants are compromised in direct defence against the larval leafminers and in attracting parasitoids, they are less attractive to adult flies compared with WT plants. Moreover, in comparison to other genotypes, the 35S::prosys plant displays greater direct and constitutive indirect defences, but reduced success of parasitism by parasitoids. Taken together, these results suggest that there are distinguished ecological trade-offs between JA-dependent direct and indirect defences in genetically modified plants whose fitness should be assessed in tritrophic systems and under natural conditions.

  12. Growth of Arabidopsis seedlings on high fungal doses of Piriformospora indica has little effect on plant performance, stress, and defense gene expression in spite of elevated jasmonic acid and jasmonic acid-isoleucine levels in the roots.

    PubMed

    Vahabi, Khabat; Camehl, Iris; Sherameti, Irena; Oelmüller, Ralf

    2013-11-01

    The endophytic fungus Piriformospora indica colonizes the roots of many plant species including Arabidopsis and promotes their performance, biomass, and seed production as well as resistance against biotic and abiotic stress. Imbalances in the symbiotic interaction such as uncontrolled fungal growth result in the loss of benefits for the plants and activation of defense responses against the microbe. We exposed Arabidopsis seedlings to a dense hyphal lawn of P. indica. The seedlings continue to grow, accumulate normal amounts of chlorophyll, and the photosynthetic parameters demonstrate that they perform well. In spite of high fungal doses around the roots, the fungal material inside the roots was not significantly higher when compared with roots that live in a beneficial symbiosis with P. indica. Fifteen defense- and stress-related genes including PR2, PR3, PAL2, and ERF1 are only moderately upregulated in the roots on the fungal lawn, and the seedlings did not accumulate H2O2/radical oxygen species. However, accumulation of anthocyanin in P. indica-exposed seedlings indicates stress symptoms. Furthermore, the jasmonic acid (JA) and jasmonic acid-isoleucine (JA-Ile) levels were increased in the roots, and consequently PDF1.2 and a newly characterized gene for a 2-oxoglurate and Fe2+ -dependent oxygenase were upregulated more than 7-fold on the dense fungal lawn, in a JAR1- and EIN3-dependent manner. We conclude that growth of A. thaliana seedlings on high fungal doses of P. indica has little effect on the overall performance of the plants although elevated JA and JA-Ile levels in the roots induce a mild stress or defense response.

  13. Chestnut species and jasmonic acid treatment influence development and community interactions of galls produced by the Asian chestnut gall wasp, Dryocosmus kuriphilus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Jasmonic acid (JA) is a plant-signaling compound involved in defenses against insects and pathogens, and in the regulation of nutrient partitioning. Gall wasps (Hymenoptera: Cynipidae) induce the formation of structures (galls) on their host plants which house immature wasps and provide them with nu...

  14. Jasmonic acid causes short- and long-term alterations to the transcriptome and the expression of defense genes in sugarbeet roots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Jasmonic acid (JA) induces native defense responses in plants and increases the resistance of postharvest sugarbeet roots to three common storage-rot causing organisms. To gain insight into the defense responses induced by JA in harvested sugarbeet roots, RNA was isolated from roots treated with wat...

  15. Physcomitrella patens activates reinforcement of the cell wall, programmed cell death and accumulation of evolutionary conserved defence signals, such as salicylic acid and 12-oxo-phytodienoic acid, but not jasmonic acid, upon Botrytis cinerea infection.

    PubMed

    Ponce De León, Inés; Schmelz, Eric A; Gaggero, Carina; Castro, Alexandra; Álvarez, Alfonso; Montesano, Marcos

    2012-10-01

    The moss Physcomitrella patens is an evolutionarily basal model system suitable for the analysis of plant defence responses activated after pathogen assault. Upon infection with the necrotroph Botrytis cinerea, several defence mechanisms are induced in P. patens, including the fortification of the plant cell wall by the incorporation of phenolic compounds and the induced expression of related genes. Botrytis cinerea infection also activates the accumulation of reactive oxygen species and cell death with hallmarks of programmed cell death in moss tissues. Salicylic acid (SA) levels also increase after fungal infection, and treatment with SA enhances transcript accumulation of the defence gene phenylalanine ammonia-lyase (PAL) in P. patens colonies. The expression levels of the genes involved in 12-oxo-phytodienoic acid (OPDA) synthesis, including lipoxygenase (LOX) and allene oxide synthase (AOS), increase in P. patens gametophytes after pathogen assault, together with a rise in free linolenic acid and OPDA concentrations. However, jasmonic acid (JA) could not be detected in healthy or infected tissues of this plant. Our results suggest that, although conserved defence signals, such as SA and OPDA, are synthesized and are probably involved in the defence response of P. patens against B. cinerea infection, JA production appears to be missing. Interestingly, P. patens responds to OPDA and methyl jasmonate by reducing moss colony growth and rhizoid length, suggesting that jasmonate perception is present in mosses. Thus, P. patens can provide clues with regard to the evolution of different defence pathways in plants, including signalling and perception of OPDA and jasmonates in nonflowering and flowering plants.

  16. The phytoplasmal virulence factor TENGU causes plant sterility by downregulating of the jasmonic acid and auxin pathways

    PubMed Central

    Minato, Nami; Himeno, Misako; Hoshi, Ayaka; Maejima, Kensaku; Komatsu, Ken; Takebayashi, Yumiko; Kasahara, Hiroyuki; Yusa, Akira; Yamaji, Yasuyuki; Oshima, Kenro; Kamiya, Yuji; Namba, Shigetou

    2014-01-01

    Despite plants infected by pathogens are often unable to produce offspring, it remains unclear how sterility is induced in host plants. In this study, we demonstrate that TENGU, a phytoplasmal virulence peptide known as a dwarfism inducer, acts as an inducer of sterility. Transgenic expression of TENGU induced both male and female sterility in Arabidopsis thaliana flowers similar to those observed in double knockout mutants of auxin response factor 6 (ARF6) and ARF8, which are known to regulate floral development in a jasmonic acid (JA)-dependent manner. Transcripts of ARF6 and ARF8 were significantly decreased in both tengu-transgenic and phytoplasma-infected plants. Furthermore, JA and auxin levels were actually decreased in tengu-transgenic buds, suggesting that TENGU reduces the endogenous levels of phytohormones by repressing ARF6 and ARF8, resulting in impaired flower maturation. TENGU is the first virulence factor with the effects on plant reproduction by perturbation of phytohormone signaling. PMID:25492247

  17. A mathematical model of the interaction of abscisic acid, ethylene and methyl jasmonate on stomatal closure in plants

    PubMed Central

    Hernandez, Bryan Sapon

    2017-01-01

    Stomatal closure is affected by various stimuli such as light, atmospheric carbon dioxide concentration, humidity and phytohormones. Our research focuses on phytohormones, specifically: abscisic acid (ABA), ethylene (ET) and methyl jasmonate (MeJA) that are responsible for the regulation of several plant processes, especially in guard cell signalling. While several studies show that these three phytohormones cause stomatal closure in plants, only two studies are notable for establishing a mathematical model of guard cell signalling involving phytohormones. Those two studies employed Boolean modelling and mechanistic ordinary differential equations modelling. In this study, we propose a new mathematical model of guard cell transduction network for stomatal closure using continuous logical modelling framework. Results showed how the different components of the network function. Furthermore, the model verified the role of antioxidants in the closure mechanism, and the diminished closure level of stomata with combined ABA-ET stimulus. The analysis was extended to ABA-ET-MeJA crosstalk. PMID:28182683

  18. Enhanced glucosinolates in root exudates of Brassica rapa ssp. rapa mediated by salicylic acid and methyl jasmonate.

    PubMed

    Schreiner, Monika; Krumbein, Angelika; Knorr, Dietrich; Smetanska, Iryna

    2011-02-23

    Elicitation studies with salicylic acid (SA) and methyl jasmonate (MJ) inducing a targeted rhizosecretion of high levels of anticarcinogenic glucosinolates in Brassica rapa ssp. rapa plants were conducted. Elicitor applications not only led to an accumulation of individual indole glucosinolates and the aromatic 2-phenylethyl glucosinolate in the turnip organs but also in turnip root exudates. This indicates an extended systemic response, which comprises the phyllosphere with all aboveground plant organs and the rhizosphere including the belowground root system and also root exudates. Both elicitor applications induced a doubling in 2-phenylethyl glucosinolate in root exudates, whereas application of MJ enhanced rhizosecreted indole glucosinolates up to 4-fold. In addition, the time course study revealed that maximal elicitation was observed on the 10th day of SA and MJ treatment. This study may provide an essential contribution using these glucosinolates as bioactive additives in functional foods and nutraceuticals.

  19. In situ fluorescence labelling of jasmonic acid binding sites in plant tissues with cadmium-free quantum dots.

    PubMed

    Liao, Qiumei; Yu, Ying; Cao, Yujuan; Lin, Bixia; Wei, Jingjing

    2015-02-01

    The fluorescence labelling of plant hormone binding sites is an important analytical technique in research on the molecular mechanisms of plant hormone activities. The authors synthesised a jasmonic acid (JA)-conjugated ZnS:Mn quantum dot (QD) probe, with a cubic structure and average hydrodynamic sizes of about 17.0 nm. The maximum fluorescence emission of the probe was recorded at about 585 nm. The probe was used for fluorescence labelling of JA binding sites in mung bean seedling tissues. Analysis revealed that the probe exhibited high selectivity to JA binding sites and good performance in eliminating interference from background fluorescence in plant tissues. In addition, the probe did not exhibit any apparent biotoxicity, and is much more suitable than probes constructed from CdTe QDs for the analysis of biological samples.

  20. SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV) by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum)

    PubMed Central

    Li, Yunzhou; Qin, Lei; Zhao, Jingjing; Muhammad, Tayeb; Cao, Hehe; Li, Hailiang; Zhang, Yan; Liang, Yan

    2017-01-01

    Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3) in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L.) infected with tomato yellow leaf curl virus (TYLCV). There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA) and jasmonic acid (JA) defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA) both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II) and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways. PMID:28222174

  1. Jasmonic acid is a downstream component in the modulation of somatic embryogenesis by Arabidopsis Class 2 phytoglobin

    PubMed Central

    Mira, Mohamed M.; Wally, Owen S. D.; Elhiti, Mohamed; El-Shanshory, Adel; Reddy, Dhadi S.; Hill, Robert D.; Stasolla, Claudio

    2016-01-01

    Previous studies have shown that the beneficial effect of suppression of the Arabidopsis phytoglobin 2 gene, PGB2, on somatic embryogenesis occurs through the accumulation of nitric oxide (NO) within the embryogenic cells originating from the cultured explant. NO activates the expression of Allene oxide synthase (AOS) and Lipoxygenase 2 (LOX2), genes encoding two key enzymes of the jasmonic acid (JA) biosynthetic pathway, elevating JA content within the embryogenic tissue. The number of embryos in the single aos1-1 mutant and pgb2-aos1-1 double mutant declined, and was not rescued by increasing levels of NO stimulating embryogenesis in wild-type tissue. NO also influenced JA responses by up-regulating PLANT DEFENSIN 1 (PDF1) and JASMONATE-ZIM-PROTEIN (JAZ1), as well as down-regulating MYC2. The NO and JA modulation of MYC2 and JAZ1 controlled embryogenesis. Ectopic expression of JAZ1 or suppression of MYC2 promoted the formation of somatic embryos, while repression of JAZ1 and up-regulation of MYC2 reduced the embryogenic performance. Sustained expression of JAZ1 induced the transcription of several indole acetic acid (IAA) biosynthetic genes, resulting in higher IAA levels in the embryogenic cells. Collectively these data fit a model integrating JA in the PGB2 regulation of Arabidopsis embryogenesis. Suppression of PGB2 increases JA through NO. Elevated levels of JA repress MYC2 and induce JAZ1, favoring the accumulation of IAA in the explants and the subsequent production of somatic embryos. PMID:26962208

  2. Serotonin modulates Arabidopsis root growth via changes in reactive oxygen species and jasmonic acid-ethylene signaling.

    PubMed

    Pelagio-Flores, Ramón; Ruiz-Herrera, León Francisco; López-Bucio, José

    2016-09-01

    Serotonin (5-hydroxytryptamine) is a bioactive indoleamine with neurotransmitter function in vertebrates, which represents an emerging signaling molecule in plants, playing key roles in the development and defense. In this study, the role of reactive oxygen species (ROS) and jasmonic acid (JA)-ethylene (Et) signaling in root developmental alterations induced by serotonin was investigated. An Arabidopsis thaliana mutant defective at the RADICAL-INDUCED CELL DEATH1 (RCD1) locus was resistant to paraquat-induced ROS accumulation in primary roots and showed decreased inhibition or root growth in response to serotonin. A suite of JA- and Et-related mutants including coronatine insensitive1, jasmonic acid resistant1 (jar1), etr1, ein2 and ein3 showed tolerance to serotonin in the inhibition of primary root growth and ROS redistribution within the root tip when compared with wild-type (WT) seedlings. Competence assays between serotonin and AgNO3 , a well-known blocker of Et action, showed that primary root growth in medium supplemented with serotonin was normalized by AgNO3 , whereas roots of eto3, an Et overproducer mutant, were oversensitive to serotonin. Comparison of ROS levels in WT, etr1, jar1 and rcd1 primary root tips using the ROS-specific probe 2',7'-dichlorofluorescein diacetate and confocal imaging showed that serotonin inhibition of primary root growth likely occurs independently of its conversion into melatonin. Our results provide compelling evidence that serotonin affects ROS distribution in roots, involving RCD1 and components of the JA-Et signaling pathways.

  3. Systemic jasmonic acid modulation in mycorrhizal tomato plants and its role in induced resistance against Alternaria alternata.

    PubMed

    Nair, A; Kolet, S P; Thulasiram, H V; Bhargava, S

    2015-05-01

    Tomato plants colonised with the arbuscular mycorrhizal (AM) fungus Glomus fasciculatum show systemic induced resistance to the foliar pathogen Alternaria alternata, as observed in interactions of other AM-colonised plants with a range of pathogens. The role of jasmonic (JA) and salicylic (SA) acid in expression of this mycorrhiza-induced resistance (MIR) against A. alternata was studied by measuring: (i) activity of enzymes reported to be involved in their biosynthesis, namely lipoxygenase (LOX) and phenylammonia lyase (PAL); and (ii) levels of methyl jasmonate (MeJA) and SA. Transcript abundance of some defence genes associated with JA and SA response pathways were also studied. Both LOX and PAL activity increased twofold in response to pathogen application to control plants. AM-colonised plants had three-fold higher LOX activity compared to control plants, but unlike controls, this did not increase further in response to pathogen application. Higher LOX activity in AM-colonised plants correlated with four-fold higher MeJA in leaves of AM-colonised plants compared to controls. Treatment of plants with the JA biosynthesis inhibitor salicylhydroxamic acid (SHAM) led to 50% lower MeJA in both control and AM-colonised plants and correlated with increased susceptibility to A. alternata, suggesting a causal role for JA in expression of MIR against the pathogen. Genes involved in JA biosynthesis (OPR3) and response (COI1) showed six- and 42-fold higher expression, respectively, in leaves of AM-colonised plants compared to controls. AM-colonised plants also showed increased expression of the SA response gene PR1 and that of the wound-inducible polypeptide prosystemin. Our results suggest that the systemic increase in JA in response to AM colonisation plays a key role in expression of MIR against A. alternata.

  4. Defense Priming and Jasmonates: A Role for Free Fatty Acids in Insect Elicitor-Induced Long Distance Signaling

    PubMed Central

    Li, Ting; Cofer, Tristan; Engelberth, Marie; Engelberth, Jurgen

    2016-01-01

    Green leaf volatiles (GLV) prime plants against insect herbivore attack resulting in stronger and faster signaling by jasmonic acid (JA). In maize this response is specifically linked to insect elicitor (IE)-induced signaling processes, which cause JA accumulation not only around the damage site, but also in distant tissues, presumably through the activation of electrical signals. Here, we present additional data further characterizing these distal signaling events in maize. Also, we describe how exposure to GLV increases free fatty acid (fFA) levels in maize seedlings, but also in other plants, and how increased fFA levels affect IE-induced JA accumulation. Increased fFA, in particular α-linolenic acid (LnA), caused a significant increase in JA accumulation after IE treatment, while JA induced by mechanical wounding (MW) alone was not affected. We also identified treatments that significantly decreased certain fFA level including simulated wind and rain. In such treated plants, IE-induced JA accumulation was significantly reduced when compared to un-moved control plants, while MW-induced JA accumulation was not significantly affected. Since only IE-induced JA accumulation was altered by changes in the fFA composition, we conclude that changing levels of fFA affect primarily IE-induced signaling processes rather than serving as a substrate for JA. PMID:27135225

  5. Jasmonic acid-dependent and -independent signaling pathways control wound-induced gene activation in Arabidopsis thaliana.

    PubMed Central

    Titarenko, E; Rojo, E; León, J; Sánchez-Serrano, J J

    1997-01-01

    Plant response to mechanical injury includes gene activation both at the wound site and systemically in nondamaged tissues. The model developed for the wound-induced activation of the proteinase inhibitor II (Pin2) gene in potato (Solanum tuberosum) and tomato (Lycopersicon esculentum) establishes the involvement of the plant hormones abscisic acid and jasmonic acid (JA) as key components of the wound signal transduction pathway. To assess in Arabidopsis thaliana the role of these plant hormones in regulating wound-induced gene expression, we isolated wound- and JA-inducible genes by the differential mRNA display technique. Their patterns of expression upon mechanical wounding and hormonal treatments revealed differences in the spatial distribution of the transcripts and in the responsiveness of the analyzed genes to abscisic acid and JA. A correlation can be established between sensitivity to JA and the accumulation of the transcripts in systemic tissues upon wounding. A comparative study of the wound response in wild-type and JA-insensitive coi1 mutant plants indicated that in A. thaliana wound signals are transmitted via at least two different pathways. One of them does not involve JA as a mediator and is preferentially responsible for gene activation in the vicinity of the wound site, whereas the other requires JA perception and activates gene expression throughout the aerial part of the plant. PMID:9342878

  6. Salicylic Acid Suppresses Jasmonic Acid Signaling Downstream of SCFCOI1-JAZ by Targeting GCC Promoter Motifs via Transcription Factor ORA59[C][W][OA

    PubMed Central

    Van der Does, Dieuwertje; Leon-Reyes, Antonio; Koornneef, Annemart; Van Verk, Marcel C.; Rodenburg, Nicole; Pauwels, Laurens; Goossens, Alain; Körbes, Ana P.; Memelink, Johan; Ritsema, Tita; Van Wees, Saskia C.M.; Pieterse, Corné M.J.

    2013-01-01

    Antagonism between the defense hormones salicylic acid (SA) and jasmonic acid (JA) plays a central role in the modulation of the plant immune signaling network, but the molecular mechanisms underlying this phenomenon are largely unknown. Here, we demonstrate that suppression of the JA pathway by SA functions downstream of the E3 ubiquitin-ligase Skip-Cullin-F-box complex SCFCOI1, which targets JASMONATE ZIM-domain transcriptional repressor proteins (JAZs) for proteasome-mediated degradation. In addition, neither the stability nor the JA-induced degradation of JAZs was affected by SA. In silico promoter analysis of the SA/JA crosstalk transcriptome revealed that the 1-kb promoter regions of JA-responsive genes that are suppressed by SA are significantly enriched in the JA-responsive GCC-box motifs. Using GCC:GUS lines carrying four copies of the GCC-box fused to the β-glucuronidase reporter gene, we showed that the GCC-box motif is sufficient for SA-mediated suppression of JA-responsive gene expression. Using plants overexpressing the GCC-box binding APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factors ERF1 or ORA59, we found that SA strongly reduces the accumulation of ORA59 but not that of ERF1. Collectively, these data indicate that the SA pathway inhibits JA signaling downstream of the SCFCOI1-JAZ complex by targeting GCC-box motifs in JA-responsive promoters via a negative effect on the transcriptional activator ORA59. PMID:23435661

  7. The epiphytic fungus Pseudozyma aphidis induces jasmonic acid- and salicylic acid/nonexpressor of PR1-independent local and systemic resistance.

    PubMed

    Buxdorf, Kobi; Rahat, Ido; Gafni, Aviva; Levy, Maggie

    2013-04-01

    Pseudozyma spp. are yeast-like fungi, classified in the Ustilaginales, which are mostly epiphytic or saprophytic and are not pathogenic to plants. Several Pseudozyma species have been reported to exhibit biological activity against powdery mildews. However, previous studies have reported that Pseudozyma aphidis, which can colonize plant surfaces, is not associated with the collapse of powdery mildew colonies. In this report, we describe a novel P. aphidis strain and study its interactions with its plant host and the plant pathogen Botrytis cinerea. This isolate was found to secrete extracellular metabolites that inhibit various fungal pathogens in vitro and significantly reduce B. cinerea infection in vivo. Moreover, P. aphidis sensitized Arabidopsis (Arabidopsis thaliana) plants' defense machinery via local and systemic induction of pathogenesis-related1 (PR1) and plant defensin1.2 (PDF1.2) expression. P. aphidis also reduced B. cinerea infection, locally and systemically, in Arabidopsis mutants impaired in jasmonic acid (JA) or salicylic acid (SA) signaling. Thus, in addition to direct inhibition, P. aphidis may inhibit B. cinerea infection via induced resistance in a manner independent of SA, JA, and Nonexpressor of PR1 (NPR1). P. aphidis primed the plant defense machinery and induced stronger activation of PDF1.2 after B. cinerea infection. Finally, P. aphidis fully or partially reconstituted PR1 and PDF1.2 expression in npr1-1 mutant and in plants with the SA hydroxylase NahG transgene, but not in a jasmonate resistant1-1 mutant, after B. cinerea infection, suggesting that P. aphidis can bypass the SA/NPR1, but not JA, pathway to activate PR genes. Thus, either partial gene activation is sufficient to induce resistance, or the resistance is not directed solely through PR1 and PDF1.2 but probably through other pathogen-resistance genes or pathways as well.

  8. PgLOX6 encoding a lipoxygenase contributes to jasmonic acid biosynthesis and ginsenoside production in Panax ginseng

    PubMed Central

    Rahimi, Shadi; Kim, Yu-Jin; Sukweenadhi, Johan; Zhang, Dabing; Yang, Deok-Chun

    2016-01-01

    Ginsenosides, the valuable pharmaceutical compounds in Panax ginseng, are triterpene saponins that occur mainly in ginseng plants. It was shown that in vitro treatment with the phytohormone jasmonic acid (JA) is able to increase ginsenoside production in ginseng plants. To understand the molecular link between JA biosynthesis and ginsenoside biosynthesis, we identified a JA biosynthetic 13-lipoxygenase gene (PgLOX6) in P. ginseng that promotes ginsenoside production. The expression of PgLOX6 was high in vascular bundles, which corresponds with expression of ginsenoside biosynthetic genes. Consistent with the role of PgLOX6 in synthesizing JA and promoting ginsenoside synthesis, transgenic plants overexpressing PgLOX6 in Arabidopsis had increased amounts of JA and methyl jasmonate (MJ), increased expression of triterpene biosynthetic genes such as squalene synthase (AtSS1) and squalene epoxidase (AtSE1), and increased squalene content. Moreover, transgenic ginseng roots overexpressing PgLOX6 had around 1.4-fold increased ginsenoside content and upregulation of ginsenoside biosynthesis-related genes including PgSS1, PgSE1, and dammarenediol synthase (PgDDS), which is similar to that of treatment with MJ. However, MJ treatment of transgenic ginseng significantly enhanced JA and MJ, associated with a 2.8-fold increase of ginsenoside content compared with the non-treated, non-transgenic control plant, which was 1.4 times higher than the MJ treatment effect on non-transgenic plants. These results demonstrate that PgLOX6 is responsible for the biosynthesis of JA and promotion of the production of triterpenoid saponin through up-regulating the expression of ginsenoside biosynthetic genes. This work provides insight into the role of JA in biosynthesizing secondary metabolites and provides a molecular tool for increasing ginsenoside production. PMID:27811076

  9. Enhanced daidzin production from jasmonic and acetyl salicylic acid elicited hairy root cultures of Psoralea corylifolia L. (Fabaceae).

    PubMed

    Zaheer, Mohd; Reddy, Vudem Dashavantha; Giri, Charu Chandra

    2016-07-01

    Daidzin (7-O-glucoside of daidzein) has several pharmacological benefits in herbal remedy, as antioxidant and shown antidipsotropic activity. Hairy root culture of Psoralea corylifolia L. was developed for biomass and enhanced daidzin production using signalling compounds such as jasmonic acid (JA) and acetyl salicylic acid (ASA). Best response of 2.8-fold daidzin (5.09% DW) with 1 μM JA treatment after second week and 7.3-fold (3.43% DW) with 10 μM JA elicitation after 10th week was obtained from hairy roots compared to untreated control. ASA at 10 μM promoted 1.7-fold increase in daidzin (1.49% DW) content after seventh week compared to control (0.83% DW). Addition of 25 μM ASA resulted in 1.44% DW daidzin (1.5-fold increase) with 0.91% DW in control after fifth week and 1.44% DW daidzin (2.3-fold increase) after eighth week when compared to untreated control (0.62% DW). Reduced biomass with increased daidzin content was facilitated by elicited hairy root cultures.

  10. ORA59 and EIN3 interaction couples jasmonate-ethylene synergistic action to antagonistic salicylic acid regulation of PDF expression.

    PubMed

    He, Xiang; Jiang, Jishan; Wang, Changquan; Dehesh, Katayoon

    2017-02-07

    Hormonal crosstalk is central for tailoring plant responses to the nature of challenges encountered. The role of antagonism between the two major defense hormones, salicylic acid (SA) and jasmonic acid (JA), and modulation of this interplay by ethylene (ET) in favor of JA signaling pathway in plant stress responses is well recognized, but the underlying mechanism is not fully understood. Here, we show the opposing function of two transcription factors, ethylene insensitive3 (EIN3) and EIN3-Like1 (EIL1), in SA-mediated suppression and JA-mediated activation of PLANT DEFENSIN1.2 (PDF1.2). This functional duality is mediated via their effect on protein, not transcript levels of the PDF1.2 transcriptional activator octadecanoid-responsive arabidopsis59 (ORA59). Specifically, JA induces ORA59 protein levels independently of EIN3/EIL1, whereas SA reduces the protein levels dependently of EIN3/EIL1. Co-infiltration assays revealed nuclear co-localization of ORA59 and EIN3, and split-luciferase together with yeast-two-hybrid assays established their physical interaction. The functional ramification of the physical interaction is EIN3-dependent degradation of ORA59 by the 26S proteasome. These findings allude to SA-responsive reduction of ORA59 levels mediated by EIN3 binding to and targeting of ORA59 for degradation, thus nominating ORA59 pool as a coordination node for the antagonistic function of ET/JA and SA.

  11. Ammonium secretion during Colletotrichum coccodes infection modulates salicylic and jasmonic acid pathways of ripe and unripe tomato fruit.

    PubMed

    Alkan, Noam; Fluhr, Robert; Prusky, Dov

    2012-01-01

    The postharvest pathogens Colletotrichum coccodes remains quiescent after infection of unripe fruit. However, during fruit ripening, the pathogen assumes a necrotrophic life style, rapidly colonizing the tissue. C. coccodes secretes ammonium during germination and colonization of host tissue that induces host programmed cell death. We further examined the role of ammonia in the infection process by analyzing transcriptome expression from infected and ammonia-treated fruit tissue compared with healthy tissue. The analysis revealed 82 and 237 common upregulated and downregulated genes, respectively. Quantitative reverse-transcriptase polymerase chain reaction analysis of select transcripts in normal and transgenic NADPH oxidase antisense plants revealed that their expression was NADPH oxidase dependent. Common-upregulated genes showed overrepresentation of salicylic acid (SA)-dependent genes as well as genes related to biotic stress. The downregulated genes showed overrepresentation of jasmonic acid (JA)-dependent genes. Indeed, direct application of SA to the fruit enhanced C. coccodes necrotrophic colonization, whereas the application of JA delayed colonization. Importantly, green fruit and red fruit displayed similar gene expression patterns although only red fruit is susceptible to colonization. Thus, it is likely that the resistance of green fruit to C. coccodes colonization is due to additional factors.

  12. Onset of herbivore-induced resistance in systemic tissue primed for jasmonate-dependent defenses is activated by abscisic acid.

    PubMed

    Vos, Irene A; Verhage, Adriaan; Schuurink, Robert C; Watt, Lewis G; Pieterse, Corné M J; Van Wees, Saskia C M

    2013-01-01

    In Arabidopsis, the MYC2 transcription factor on the one hand and the AP2/ERF transcription factors ORA59 and ERF1 on the other hand regulate distinct branches of the jasmonic acid (JA) signaling pathway in an antagonistic fashion, co-regulated by abscisic acid (ABA) and ethylene, respectively. Feeding by larvae of the specialist herbivorous insect Pieris rapae (small cabbage white butterfly) results in activation of the MYC-branch and concomitant suppression of the ERF-branch in insect-damaged leaves. Here we investigated differential JA signaling activation in undamaged systemic leaves of P. rapae-infested plants. We found that the MYC2 transcription factor gene was induced both in the local insect-damaged leaves and the systemic undamaged leaves of P. rapae-infested Arabidopsis plants. However, in contrast to the insect-damaged leaves, the undamaged tissue did not show activation of the MYC-branch marker gene VSP1. Comparison of the hormone signal signature revealed that the levels of JA and (+)-7-iso-jasmonoyl-L-isoleucine raised to similar extents in locally damaged and systemically undamaged leaves, but the production of ABA and the JA precursor 12-oxo-phytodienoic acid was enhanced only in the local herbivore-damaged leaves, and not in the distal undamaged leaves. Challenge of undamaged leaves of pre-infested plants with either P. rapae larvae or exogenously applied ABA led to potentiated expression levels of MYC2 and VSP1, with the latter reaching extremely high expression levels. Moreover, P. rapae-induced resistance, as measured by reduction of caterpillar growth on pre-infested plants, was blocked in the ABA biosynthesis mutant aba2-1, that was also impaired in P. rapae-induced expression of VSP1. Together, these results suggest that ABA is a crucial regulator of herbivore-induced resistance by activating primed JA-regulated defense responses upon secondary herbivore attack in Arabidopsis.

  13. Stimulation of jasmonic acid production in Zea mays L. infected by the maize rough dwarf virus-Río Cuarto. Reversion of symptoms by salicylic acid.

    PubMed

    Vigliocco, A; Bonamico, B; Alemano, S; Miersch, O; Abdala, G

    2002-12-01

    In the present paper we study the possible biological relevance of endogenous jasmonic acid (JA) and exogenous salicylic acid (SA) in a plant-microbial system maize-virus. The virus disease "Mal de Río Cuarto" is caused by the maize rough dwarf virus-Río Cuarto. The characteristic symptoms are the appearance of galls or "enations" in leaves, shortening of the stem internodes, poor radical system and general stunting. Changes in JA and protein pattern in maize control and infected plants of a virus-tolerant cultivar were investigated. Healthy and infected-leaf discs were collected for JA measurement at different post-infection times (20, 40, 60 and 68 days). JA was also measured in roots on day 60 after infection. For SDS-PAGE protein analysis, leaf discs were also harvested on day 60 after infection. Infected leaves showed higher levels of JA than healthy leaves, and the rise in endogenous JA coincided with the enation formation. The soluble protein amount did not show differences between infected and healthy leaves; moreover, no difference in the expression of soluble protein was revealed by SDS-PAGE. Our results show that the octadecanoid pathway was stimulated in leaves and roots of the tolerant maize cultivar when infected by this virus. This finding, together with fewer plants with the disease symptoms, suggest that higher foliar and roots JA content may be related to disease tolerance. SA exogenous treatment caused the reversion of the dwarfism symptom.

  14. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis

    PubMed Central

    Song, Geun C.; Choi, Hye K.; Ryu, Choong-Min

    2015-01-01

    3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 μM and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR) gene expression levels associated with defense signaling through salicylic acid (SA), jasmonic acid (JA), and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved SA and JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen. PMID:26500665

  15. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis.

    PubMed

    Song, Geun C; Choi, Hye K; Ryu, Choong-Min

    2015-01-01

    3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 μM and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR) gene expression levels associated with defense signaling through salicylic acid (SA), jasmonic acid (JA), and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved SA and JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.

  16. Phloem sugar flux and jasmonic acid-responsive cell wall invertase control extrafloral nectar secretion in Ricinus communis.

    PubMed

    Millán-Cañongo, Cynthia; Orona-Tamayo, Domancar; Heil, Martin

    2014-07-01

    Plants secrete extrafloral nectar (EFN) that attracts predators. The efficiency of the resulting anti-herbivore defense depends on the quantity and spatial distribution of EFN. Thus, according to the optimal defense hypothesis (ODH), plants should secrete EFN on the most valuable organs and when herbivore pressure is high. Ricinus communis plants secreted most EFN on the youngest (i.e., most valuable) leaves and after the simulation of herbivory via the application of jasmonic acid (JA). Here, we investigated the physiological mechanisms that might produce these seemingly adaptive spatiotemporal patterns. Cell wall invertase (CWIN; EC 3.2.1.26) was most active in the hours before peak EFN secretion, its decrease preceded the decrease in EFN secretion, and CWIN activity was inducible by JA. Thus, CWIN appears to be a central player in EFN secretion: its activation by JA is likely to cause the induction of EFN secretion after herbivory. Shading individual leaves decreased EFN secretion locally on these leaves with no effect on CWIN activity in the nectaries, which is likely to be because it decreased the content of sucrose, the substrate of CWIN, in the phloem. Our results demonstrate how the interplay of two physiological processes can cause ecologically relevant spatiotemporal patterns in a plant defense trait.

  17. Plants Know Where It Hurts: Root and Shoot Jasmonic Acid Induction Elicit Differential Responses in Brassica oleracea

    PubMed Central

    Tytgat, Tom O.G.; Verhoeven, Koen J. F.; Jansen, Jeroen J.; Raaijmakers, Ciska E.; Bakx-Schotman, Tanja; McIntyre, Lauren M.; van der Putten, Wim H.; Biere, Arjen; van Dam, Nicole M.

    2013-01-01

    Plants respond to herbivore attack by rapidly inducing defenses that are mainly regulated by jasmonic acid (JA). Due to the systemic nature of induced defenses, attack by root herbivores can also result in a shoot response and vice versa, causing interactions between above- and belowground herbivores. However, little is known about the molecular mechanisms underlying these interactions. We investigated whether plants respond differently when roots or shoots are induced. We mimicked herbivore attack by applying JA to the roots or shoots of Brassica oleracea and analyzed molecular and chemical responses in both organs. In shoots, an immediate and massive change in primary and secondary metabolism was observed. In roots, the JA-induced response was less extensive and qualitatively different from that in the shoots. Strikingly, in both roots and shoots we also observed differential responses in primary metabolism, development as well as defense specific traits depending on whether the JA induction had been below- or aboveground. We conclude that the JA response is not only tissue-specific but also dependent on the organ that was induced. Already very early in the JA signaling pathway the differential response was observed. This indicates that both organs have a different JA signaling cascade, and that the signal eliciting systemic responses contains information about the site of induction, thus providing plants with a mechanism to tailor their responses specifically to the organ that is damaged. PMID:23776489

  18. Transcript profile analysis reveals important roles of jasmonic acid signalling pathway in the response of sweet potato to salt stress.

    PubMed

    Zhang, Huan; Zhang, Qian; Zhai, Hong; Li, Yan; Wang, Xiangfeng; Liu, Qingchang; He, Shaozhen

    2017-01-13

    Sweet potato is an important food and bio-energy crop, and investigating the mechanisms underlying salt tolerance will provide information for salt-tolerant breeding of this crop. Here, the root transcriptomes of the salt-sensitive variety Lizixiang and the salt-tolerant line ND98 were compared to identify the genes and pathways involved in salt stress responses. In total, 8,744 and 10,413 differentially expressed genes (DEGs) in Lizixiang and ND98, respectively, were involved in salt responses. A lower DNA methylation level was detected in ND98 than in Lizixiang. In both genotypes, the DEGs, which function in phytohormone synthesis and signalling and ion homeostasis, may underlie the different degrees of salt tolerance. Significant up-regulations of the genes involved in the jasmonic acid (JA) biosynthesis and signalling pathways and ion transport, more accumulation of JA, a higher degree of stomatal closure and a lower level of Na(+) were found in ND98 compared to Lizixiang. This is the first report on transcriptome responses to salt tolerance in sweet potato. These results reveal that the JA signalling pathway plays important roles in the response of sweet potato to salt stress. This study provides insights into the mechanisms and genes involved in the salt tolerance of sweet potato.

  19. Phospholipidic signaling and vanillin production in response to salicylic acid and methyl jasmonate in Capsicum chinense J. cells.

    PubMed

    Altúzar-Molina, Alma R; Muñoz-Sánchez, J Armando; Vázquez-Flota, Felipe; Monforte-González, Miriam; Racagni-Di Palma, Graciela; Hernández-Sotomayor, S M Teresa

    2011-02-01

    The phospholipidic signal transduction system involves generation of second messengers by hydrolysis or changes in phosphorylation state. Several studies have shown that the signaling pathway forms part of plant response to phytoregulators such as salicylic acid (SA) and methyl jasmonate (MJ), which have been widely used to stimulate secondary metabolite production in cell cultures. An evaluation was made of the effect of SA and MJ on phospholipidic signaling and capsaicinoid production in Capsicum chinense Jacq. suspension cells. Treatment with SA inhibited phospholipase C (PLC) (EC: 3.1.4.3) and phospholipase D (PLD) (EC: 3.1.4.4) activities in vitro, but increased lipid kinase activities in vitro at different SA concentrations. Treatment with MJ produced increases in PLC and PLD activities, while lipid kinase activities were variable and dose-dependent. The production of vanillin, a precursor of capsaicinoids, increased at specific SA or MJ doses. Preincubation with neomycin, a phospholipase inhibitor, before SA or MJ treatment inhibits increase in vanillin production which suggests that phospholipidic second messengers may participate in the observed increase in vanillin production.

  20. Transcript profile analysis reveals important roles of jasmonic acid signalling pathway in the response of sweet potato to salt stress

    PubMed Central

    Zhang, Huan; Zhang, Qian; Zhai, Hong; Li, Yan; Wang, Xiangfeng; Liu, Qingchang; He, Shaozhen

    2017-01-01

    Sweet potato is an important food and bio-energy crop, and investigating the mechanisms underlying salt tolerance will provide information for salt-tolerant breeding of this crop. Here, the root transcriptomes of the salt-sensitive variety Lizixiang and the salt-tolerant line ND98 were compared to identify the genes and pathways involved in salt stress responses. In total, 8,744 and 10,413 differentially expressed genes (DEGs) in Lizixiang and ND98, respectively, were involved in salt responses. A lower DNA methylation level was detected in ND98 than in Lizixiang. In both genotypes, the DEGs, which function in phytohormone synthesis and signalling and ion homeostasis, may underlie the different degrees of salt tolerance. Significant up-regulations of the genes involved in the jasmonic acid (JA) biosynthesis and signalling pathways and ion transport, more accumulation of JA, a higher degree of stomatal closure and a lower level of Na+ were found in ND98 compared to Lizixiang. This is the first report on transcriptome responses to salt tolerance in sweet potato. These results reveal that the JA signalling pathway plays important roles in the response of sweet potato to salt stress. This study provides insights into the mechanisms and genes involved in the salt tolerance of sweet potato. PMID:28084460

  1. Meristem maintenance, auxin, jasmonic and abscisic acid pathways as a mechanism for phenotypic plasticity in Antirrhinum majus

    NASA Astrophysics Data System (ADS)

    Weiss, Julia; Alcantud-Rodriguez, Raquel; Toksöz, Tugba; Egea-Cortines, Marcos

    2016-01-01

    Plants grow under climatic changing conditions that cause modifications in vegetative and reproductive development. The degree of changes in organ development i.e. its phenotypic plasticity seems to be determined by the organ identity and the type of environmental cue. We used intraspecific competition and found that Antirrhinum majus behaves as a decoupled species for lateral organ size and number. Crowding causes decreases in leaf size and increased leaf number whereas floral size is robust and floral number is reduced. Genes involved in shoot apical meristem maintenance like ROA and HIRZ, cell cycle (CYCD3a; CYCD3b, HISTONE H4) or organ polarity (GRAM) were not significantly downregulated under crowding conditions. A transcriptomic analysis of inflorescence meristems showed Gene Ontology enriched pathways upregulated including Jasmonic and Abscisic acid synthesis and or signalling. Genes involved in auxin synthesis such as AmTAR2 and signalling AmANT were not affected by crowding. In contrast, AmJAZ1, AmMYB21, AmOPCL1 and AmABA2 were significantly upregulated. Our work provides a mechanistic working hypothesis where a robust SAM and stable auxin signalling enables a homogeneous floral size while changes in JA and ABA signalling maybe responsible for the decreased leaf size and floral number.

  2. Combined toxicity of cadmium and copper in Avicennia marina seedlings and the regulation of exogenous jasmonic acid.

    PubMed

    Yan, Zhongzheng; Li, Xiuzhen; Chen, Jun; Tam, Nora Fung-Yee

    2015-03-01

    Seedlings of Avicennia marina were exposed to single and combined metal treatments of cadmium (Cd) and copper (Cu) in a factorial design, and the combined toxicity of Cu and Cd was tested. The effects of the exogenous jasmonic acid (JA) on chlorophyll concentration, lipid peroxidation, Cd and Cu uptake, antioxidative capacity, endogenous JA concentration, and type-2 metallothionein gene (AmMT2) expression in seedlings of A. marina exposed to combined metal treatments were also investigated. A binary mixture of low-dose Cd (9 µmolL(-1)) and high-dose Cu (900 µmolL(-1)) showed toxicity to the seedlings, indicated by the significant augmentation in leaf malondialdehyde (MDA) and reduction in leaf chlorophylls. The toxicity of the combined metals was significantly alleviated by the addition of exogenous JA at 1 µmolL(-1), and the chlorophyll and MDA contents were found to be restored to levels comparable to those of the control. Compare to treatment with Cd and Cu only, 1 and 10 µmolL(-1) JA significantly enhanced the ascorbate peroxidase activity, and 10 µmolL(-1) JA significantly decreased the uptake of Cd in A. marina leaves. The relative expression of leaf AmMT2 gene was also significantly enhanced by 1 and 10 µmolL(-1) JA, which helped reduce Cd toxicity in A. marina seedlings.

  3. The Glucosinolate Biosynthetic Gene AOP2 Mediates Feed-back Regulation of Jasmonic Acid Signaling in Arabidopsis.

    PubMed

    Burow, Meike; Atwell, Susanna; Francisco, Marta; Kerwin, Rachel E; Halkier, Barbara A; Kliebenstein, Daniel J

    2015-08-01

    Survival in changing and challenging environments requires an organism to efficiently obtain and use its resources. Due to their sessile nature, it is particularly critical for plants to dynamically optimize their metabolism. In plant primary metabolism, metabolic fine-tuning involves feed-back mechanisms whereby the output of a pathway controls its input to generate a precise and robust response to environmental changes. By contrast, few studies have addressed the potential for feed-back regulation of secondary metabolism. In Arabidopsis, accumulation of the defense compounds glucosinolates has previously been linked to genetic variation in the glucosinolate biosynthetic gene AOP2. AOP2 expression can increase the transcript levels of two known regulators (MYB28 and MYB29) of the pathway, suggesting that AOP2 plays a role in positive feed-back regulation controlling glucosinolate biosynthesis. We generated mutants affecting AOP2, MYB28/29, or both. Transcriptome analysis of these mutants identified a so far unrecognized link between AOP2 and jasmonic acid (JA) signaling independent of MYB28 and MYB29. Thus, AOP2 is part of a regulatory feed-back loop linking glucosinolate biosynthesis and JA signaling and thereby allows the glucosinolate pathway to influence JA sensitivity. The discovery of this regulatory feed-back loop provides insight into how plants optimize the use of resources for defensive metabolites.

  4. Meristem maintenance, auxin, jasmonic and abscisic acid pathways as a mechanism for phenotypic plasticity in Antirrhinum majus

    PubMed Central

    Weiss, Julia; Alcantud-Rodriguez, Raquel; Toksöz, Tugba; Egea-Cortines, Marcos

    2016-01-01

    Plants grow under climatic changing conditions that cause modifications in vegetative and reproductive development. The degree of changes in organ development i.e. its phenotypic plasticity seems to be determined by the organ identity and the type of environmental cue. We used intraspecific competition and found that Antirrhinum majus behaves as a decoupled species for lateral organ size and number. Crowding causes decreases in leaf size and increased leaf number whereas floral size is robust and floral number is reduced. Genes involved in shoot apical meristem maintenance like ROA and HIRZ, cell cycle (CYCD3a; CYCD3b, HISTONE H4) or organ polarity (GRAM) were not significantly downregulated under crowding conditions. A transcriptomic analysis of inflorescence meristems showed Gene Ontology enriched pathways upregulated including Jasmonic and Abscisic acid synthesis and or signalling. Genes involved in auxin synthesis such as AmTAR2 and signalling AmANT were not affected by crowding. In contrast, AmJAZ1, AmMYB21, AmOPCL1 and AmABA2 were significantly upregulated. Our work provides a mechanistic working hypothesis where a robust SAM and stable auxin signalling enables a homogeneous floral size while changes in JA and ABA signalling maybe responsible for the decreased leaf size and floral number. PMID:26804132

  5. Jasmonic acid affects plant morphology and calcium-dependent protein kinase expression and activity in Solanum tuberosum.

    PubMed

    Ulloa, Rita M; Raíces, Marcela; MacIntosh, Gustavo C; Maldonado, Sara; Téllez-Iñón, María T

    2002-07-01

    The effect of jasmonic acid (JA) on plant growth and on calcium-dependent protein kinase (CDPK) activity and expression was studied in non-photoperiodic potato plants, Solanum tuberosum L. var. Spunta, grown in vitro. Stem cuttings were grown for 45 days (long treatment, LT) in MS medium with increasing concentrations of JA. For short treatments (ST) adult plants grown in MS were transferred for 1, 4 and 20 h to JA containing media. During the LT, low concentrations of JA promoted cell expansion and shoot elongation while higher concentrations caused growth inhibition. Under these conditions, treated plants showed root shortening and tuber formation was not induced. Morphological and histochemical studies using light microscopy and TEM analysis of leaves from treated plants revealed that JA also affected subcellular organelles of mesophyll cells. Peroxisomes increased in size and number, and an autophagic process was triggered in response to high concentrations of the hormone. CDPK activity, determined in crude extracts of treated plants (LT), was inhibited (up to 80%). Plant growth and CDPK inhibition were reverted upon transfer of the plants to hormone-free medium. Soluble CDPK activity decreased in response to JA short treatment. Concomitantly, a decline in the steady state levels of StCDPK2 mRNA, a potato CDPK isoform that is expressed in leaves, was observed. These data suggest that the phytohormone down-regulated the expression and activity of the kinase.

  6. The Roles of Alpha-Momorcharin and Jasmonic Acid in Modulating the Response of Momordica charantia to Cucumber Mosaic Virus.

    PubMed

    Yang, Ting; Meng, Yao; Chen, Li-Juan; Lin, Hong-Hui; Xi, De-Hui

    2016-01-01

    Alpha-momorcharin (α-MMC) is a type-I ribosome inactivating protein with a molecular weight of 29 kDa that is found in Momordica charantia, and has been shown to be effective against a broad range of human viruses as well as having anti-tumor activities. However, the role of endogenous α-MMC under viral infection and the mechanism of the anti-viral activities of α-MMC in plants are still unknown. To study the effect of α-MMC on plant viral defense and how α-MMC increases plant resistance to virus, the M. charantia-cucumber mosaic virus (CMV) interaction system was investigated. The results showed that the α-MMC level was positively correlated with the resistance of M. charantia to CMV. α-MMC treatment could alleviate photosystem damage and enhance the ratio of glutathione/glutathione disulfide in M. charantia under CMV infection. The relationship of α-MMC and defense related phytohormones, and their roles in plant defense were further investigated. α-MMC treatment led to a significant increase of jasmonic acid (JA) and vice versa, while there was no obvious relevance between salicylic acid and α-MMC. In addition, reactive oxygen species (ROS) were induced in α-MMC-pretreated plants, in a similar way to the ROS burst in JA-pretreated plants. The production of ROS in both ibuprofen (JA inhibitor) and (α-MMC+ibuprofen)-pretreated plants was reduced markedly, leading to a greater susceptibility of M. charantia to CMV. Our results indicate that the anti-viral activities of α-MMC in M. charantia may be accomplished through the JA related signaling pathway.

  7. The Roles of Alpha-Momorcharin and Jasmonic Acid in Modulating the Response of Momordica charantia to Cucumber Mosaic Virus

    PubMed Central

    Yang, Ting; Meng, Yao; Chen, Li-Juan; Lin, Hong-Hui; Xi, De-Hui

    2016-01-01

    Alpha-momorcharin (α-MMC) is a type-I ribosome inactivating protein with a molecular weight of 29 kDa that is found in Momordica charantia, and has been shown to be effective against a broad range of human viruses as well as having anti-tumor activities. However, the role of endogenous α-MMC under viral infection and the mechanism of the anti-viral activities of α-MMC in plants are still unknown. To study the effect of α-MMC on plant viral defense and how α-MMC increases plant resistance to virus, the M. charantia–cucumber mosaic virus (CMV) interaction system was investigated. The results showed that the α-MMC level was positively correlated with the resistance of M. charantia to CMV. α-MMC treatment could alleviate photosystem damage and enhance the ratio of glutathione/glutathione disulfide in M. charantia under CMV infection. The relationship of α-MMC and defense related phytohormones, and their roles in plant defense were further investigated. α-MMC treatment led to a significant increase of jasmonic acid (JA) and vice versa, while there was no obvious relevance between salicylic acid and α-MMC. In addition, reactive oxygen species (ROS) were induced in α-MMC-pretreated plants, in a similar way to the ROS burst in JA-pretreated plants. The production of ROS in both ibuprofen (JA inhibitor) and (α-MMC+ibuprofen)-pretreated plants was reduced markedly, leading to a greater susceptibility of M. charantia to CMV. Our results indicate that the anti-viral activities of α-MMC in M. charantia may be accomplished through the JA related signaling pathway. PMID:27881976

  8. Jasmonic Acid Enhances Al-Induced Root Growth Inhibition1[OPEN

    PubMed Central

    Yang, Zhong-Bao; Ma, Yanqi

    2017-01-01

    Phytohormones such as ethylene and auxin are involved in the regulation of the aluminum (Al)-induced root growth inhibition. Although jasmonate (JA) has been reported to play a crucial role in the regulation of root growth and development in response to environmental stresses through interplay with ethylene and auxin, its role in the regulation of root growth response to Al stress is not yet known. In an attempt to elucidate the role of JA, we found that exogenous application of JA enhanced the Al-induced root growth inhibition. Furthermore, phenotype analysis with mutants defective in either JA biosynthesis or signaling suggests that JA is involved in the regulation of Al-induced root growth inhibition. The expression of the JA receptor CORONATINE INSENSITIVE1 (COI1) and the key JA signaling regulator MYC2 was up-regulated in response to Al stress in the root tips. This process together with COI1-mediated Al-induced root growth inhibition under Al stress was controlled by ethylene but not auxin. Transcriptomic analysis revealed that many responsive genes under Al stress were regulated by JA signaling. The differential responsive of microtubule organization-related genes between the wild-type and coi1-2 mutant is consistent with the changed depolymerization of cortical microtubules in coi1 under Al stress. In addition, ALMT-mediated malate exudation and thus Al exclusion from roots in response to Al stress was also regulated by COI1-mediated JA signaling. Together, this study suggests that root growth inhibition is regulated by COI1-mediated JA signaling independent from auxin signaling and provides novel insights into the phytohormone-mediated root growth inhibition in response to Al stress. PMID:27932419

  9. Both the Jasmonic Acid and the Salicylic Acid Pathways Contribute to Resistance to the Biotrophic Clubroot Agent Plasmodiophora brassicae in Arabidopsis.

    PubMed

    Lemarié, Séverine; Robert-Seilaniantz, Alexandre; Lariagon, Christine; Lemoine, Jocelyne; Marnet, Nathalie; Jubault, Mélanie; Manzanares-Dauleux, Maria J; Gravot, Antoine

    2015-11-01

    The role of salicylic acid (SA) and jasmonic acid (JA) signaling in resistance to root pathogens has been poorly documented. We assessed the contribution of SA and JA to basal and partial resistance of Arabidopsis to the biotrophic clubroot agent Plasmodiophora brassicae. SA and JA levels as well as the expression of the SA-responsive genes PR2 and PR5 and the JA-responsive genes ARGAH2 and THI2.1 were monitored in infected roots of the accessions Col-0 (susceptible) and Bur-0 (partially resistant). SA signaling was activated in Bur-0 but not in Col-0. The JA pathway was weakly activated in Bur-0 but was strongly induced in Col-0. The contribution of both pathways to clubroot resistance was then assessed using exogenous phytohormone application and mutants affected in SA or JA signaling. Exogenous SA treatment decreased clubroot symptoms in the two Arabidopsis accessions, whereas JA treatment reduced clubroot symptoms only in Col-0. The cpr5-2 mutant, in which SA responses are constitutively induced, was more resistant to clubroot than the corresponding wild type, and the JA signaling-deficient mutant jar1 was more susceptible. Finally, we showed that the JA-mediated induction of NATA1 drove N(δ)-acetylornithine biosynthesis in infected Col-0 roots. The 35S::NATA1 and nata1 lines displayed reduced or enhanced clubroot symptoms, respectively, thus suggesting that in Col-0 this pathway was involved in the JA-mediated basal clubroot resistance. Overall, our data support the idea that, depending on the Arabidopsis accession, both SA and JA signaling can play a role in partial inhibition of clubroot development in compatible interactions with P. brassicae.

  10. Assessing the Role of ETHYLENE RESPONSE FACTOR Transcriptional Repressors in Salicylic Acid-Mediated Suppression of Jasmonic Acid-Responsive Genes.

    PubMed

    Caarls, Lotte; Van der Does, Dieuwertje; Hickman, Richard; Jansen, Wouter; Verk, Marcel C Van; Proietti, Silvia; Lorenzo, Oscar; Solano, Roberto; Pieterse, Corné M J; Van Wees, Saskia C M

    2016-11-10

    Salicylic acid (SA) and jasmonic acid (JA) cross-communicate in the plant immune signaling network to finely regulate induced defenses. In Arabidopsis, SA antagonizes many JA-responsive genes, partly by targeting the ETHYLENE RESPONSE FACTOR (ERF)-type transcriptional activator ORA59. Members of the ERF transcription factor family typically bind to GCC-box motifs in the promoters of JA- and ethylene-responsive genes, thereby positively or negatively regulating their expression. The GCC-box motif is sufficient for SA-mediated suppression of JA-responsive gene expression. Here, we investigated whether SA-induced ERF-type transcriptional repressors, which may compete with JA-induced ERF-type activators for binding at the GCC-box, play a role in SA/JA antagonism. We selected ERFs that are transcriptionally induced by SA and/or possess an EAR transcriptional repressor motif. Several of the 16 ERFs tested suppressed JA-dependent gene expression, as revealed by enhanced JA-induced PDF1.2 or VSP2 expression levels in the corresponding erf mutants, while others were involved in activation of these genes. However, SA could antagonize JA-induced PDF1.2 or VSP2 in all erf mutants, suggesting that the tested ERF transcriptional repressors are not required for SA/JA cross-talk. Moreover, a mutant in the co-repressor TOPLESS, that showed reduction in repression of JA signaling, still displayed SA-mediated antagonism of PDF1.2 and VSP2. Collectively, these results suggest that SA-regulated ERF transcriptional repressors are not essential for antagonism of JA-responsive gene expression by SA. We further show that de novo SA-induced protein synthesis is required for suppression of JA-induced PDF1.2, pointing to SA-stimulated production of an as yet unknown protein that suppresses JA-induced transcription.

  11. Jasmonates during senescence

    PubMed Central

    Seltmann, Martin A; Hussels, Wiebke

    2010-01-01

    Jasmonic acid and derivatives are oxylipin signaling compounds derived from linolenic acid. Jasmonates accumulate during natural and dark-induced senescence but the increase in these compounds is not essential for the initiation or progression of these senescence processes. Here we report that during natural and dark-induced senescence the increase in jasmonate levels does not trigger jasmonate signaling. Furthermore we provide evidence that jasmonate production might result from membrane turnover during dark-induced senescence. PMID:21057217

  12. Pithy protection: Nicotiana attenuata's jasmonic acid-mediated defenses are required to resist stem-boring weevil larvae.

    PubMed

    Diezel, Celia; Kessler, Danny; Baldwin, Ian T

    2011-04-01

    Folivory is the best studied plant-herbivore interaction, but it is unclear whether the signaling and resistance traits important for the defense of leaves are also important for other plant parts. Larvae of the tobacco stem weevil, Trichobaris mucorea, burrow into stems of Nicotiana attenuata and feed on the pith. Transgenic N. attenuata lines silenced in signaling and foliar defense traits were evaluated in a 2-year field study for resistance against attack by naturally occurring T. mucorea larva. Plants silenced in early jasmonic acid (JA) biosynthesis (antisense [as]-lipoxygenase3 [lox3]; inverted repeat [ir]-allene oxide cyclase), JA perception (as-coronatine insensitive1), proteinase inhibitors (ir-pi), and nicotine (ir-putrescine methyl-transferase) direct defenses and lignin (ir-cad) biosynthesis were infested more frequently than wild-type plants. Plants unable to emit C(6) aldehydes (as-hpl) had lower infestation rates, while plants silenced in late steps in JA biosynthesis (ir-acyl-coenzyme A oxidase, ir-opr) and silenced in diterpene glycoside production (ir-geranylgeranyl pyrophosphate synthase) did not differ from wild type. Pith choice assays revealed that ir-putrescine methyl-transferase, ir-coronatine insensitive1, and ir-lox3 pith, which all had diminished nicotine levels, were preferred by larvae compared to wild-type pith. The lack of preference for ir-lox2 and ir-cad piths, suggest that oviposition attraction and vascular defense, rather than pith palatability accounts for the higher attack rates observed for these plants. We conclude that traits that influence a plant's apparency, stem hardness, and pith direct defenses all contribute to resistance against this herbivore whose attack can be devastating to N. attenuata's fitness.

  13. Transcriptional profiling of Zea mays roots reveals roles for jasmonic acid and terpenoids in resistance against Phytophthora cinnamomi.

    PubMed

    Allardyce, Jane Alisa; Rookes, James Edward; Hussain, Hashmath Inayath; Cahill, David Miles

    2013-06-01

    Phytophthora cinnamomi is a soil-borne plant pathogen that has caused widespread damage to vulnerable native ecosystems and agriculture systems across the world and shows no sign of abating. Management of the pathogen in the natural environment is difficult and the options are limited. In order to discover more about how resistant plants are able to defend themselves against this generalist pathogen, a microarray study of plant gene expression following root inoculation with P. cinnamomi was undertaken. Zea mays was used as a resistant model plant, and microarray analysis was conducted using the Affymetrix GeneChip Maize Genome Array on root samples collected at 6- and 24-h post-inoculation. Over 300 genes were differentially expressed in inoculated roots compared with controls across the two time points. Following Gene Ontology enrichment analysis and REVIGO visualisation of the up-regulated genes, many were implicated in plant defence responses to biotic stress. Genes that were up-regulated included those involved in phytoalexin biosynthesis and jasmonic acid/ethylene biosynthesis and other defence-related genes including those encoding glutathione S-transferases and serine-protease inhibitors. Of particular interest was the identification of the two most highly up-regulated genes, terpene synthase11 (Tps11) and kaurene synthase2 (An2), which are both involved in production of terpenoid phytoalexins. This is the first study that has investigated gene expression at a global level in roots in response to P. cinnamomi in a model plant species and provides valuable insights into the mechanisms involved in defence.

  14. Profiling and Quantifying Differential Gene Transcription Provide Insights into Ganoderic Acid Biosynthesis in Ganoderma lucidum in Response to Methyl Jasmonate

    PubMed Central

    Shi, Liang; Mu, Da-Shuai; Jiang, Ai-Liang; Han, Qin; Zhao, Ming-Wen

    2013-01-01

    Ganoderma lucidum is a mushroom with traditional medicinal properties that has been widely used in China and other countries in Eastern Asia. Ganoderic acids (GA) produced by G. lucidum exhibit important pharmacological activities. Previous studies have demonstrated that methyl jasmonate (MeJA) is a potent inducer of GA biosynthesis and the expression of genes involved in the GA biosynthesis pathway in G. lucidum. To further explore the mechanism of GA biosynthesis, cDNA-Amplified Fragment Length Polymorphism (cDNA-AFLP) was used to identify genes that are differentially expressed in response to MeJA. Using 64 primer combinations, over 3910 transcriptionally derived fragments (TDFs) were obtained. Reliable sequence data were obtained for 390 of 458 selected TDFs. Ninety of these TDFs were annotated with known functions through BLASTX searching the GenBank database, and 12 annotated TDFs were assigned into secondary metabolic pathways by searching the KEGGPATHWAY database. Twenty-five TDFs were selected for qRT-PCR analysis to confirm the expression patterns observed with cDNA-AFLP. The qRT-PCR results were consistent with the altered patterns of gene expression revealed by the cDNA-AFLP technique. Additionally, the transcript levels of 10 genes were measured at the mycelium, primordia, and fruiting body developmental stages of G. lucidum. The greatest expression levels were reached during primordia for all of the genes except cytochrome b2 reached its highest expression level in the mycelium stage. This study not only identifies new candidate genes involved in the regulation of GA biosynthesis but also provides further insight into MeJA-induced gene expression and secondary metabolic response in G. lucidum. PMID:23762280

  15. Analysis of plant-bacteria interactions in their native habitat: bacterial communities associated with wild tobacco are independent of endogenous jasmonic acid levels and developmental stages.

    PubMed

    Santhanam, Rakesh; Groten, Karin; Meldau, Dorothea G; Baldwin, Ian T

    2014-01-01

    Jasmonic acid (JA) mediates defense responses against herbivores and necrotrophic pathogens but does it influence the recruitment of bacterial communities in the field? We conducted field and laboratory experiments with transformed Nicotiana attenuata plants deficient in jasmonate biosynthesis (irAOC) and empty vector controls (EV) to answer this question. Using both culture-dependent and independent techniques, we characterized root and leaf-associated bacterial communities over five developmental stages, from rosette through flowering of plants grown in their natural habitat. Based on the pyrosequencing results, alpha and beta diversity did not differ among EV and irAOC plants or over ontogeny, but some genera were more abundant in one of the genotypes. Furthermore, bacterial communities were significantly different among leaves and roots. Taxa isolated only from one or both plant genotypes and hence classified as 'specialists' and 'generalists' were used in laboratory tests to further evaluate the patterns observed from the field. The putative specialist taxa did not preferentially colonize the jasmonate-deficient genotype, or alter the plant's elicited phytohormone signaling. We conclude that in N. attenuata, JA signaling does not have a major effect on structuring the bacterial communities and infer that colonization of plant tissues is mainly shaped by the local soil community in which the plant grows.

  16. SGT1 regulates wounding- and herbivory-induced jasmonic acid accumulation and Nicotiana attenuata's resistance to the specialist lepidopteran herbivore Manduca sexta.

    PubMed

    Meldau, Stefan; Baldwin, Ian T; Wu, Jianqiang

    2011-03-01

    • SGT1 (suppressor of G-two allele of SKP1) is a conserved protein in all eukaryotes and is crucial for resisting pathogens in humans and plants. We studied whether SGT1 is involved in the induced defense response of a native tobacco (Nicotiana attenuata) to its natural herbivore, Manduca sexta. • We diminished NaSGT1 transcription in N. attenuata using virus-induced gene silencing (VIGS) and analysed the induced defense responses after wounding and M. sexta elicitation. • Silencing NaSGT1 highly attenuates wounding- and herbivory-induced amounts of jasmonic acid (JA) and JA-isoleucine but elevates the concentration of salicylic acid. Chemical profiling reveals that NaSGT1-silenced plants are also compromised in their ability to accumulate JA precursors produced in chloroplasts. We show that the reduced JA accumulation in NaSGT1-silenced plants is independent of the elevated salicylic acid levels. NaSGT1-silenced plants have decreased contents of defensive metabolites and have compromised resistance to M. sexta larvae. Transcript analyses after methyl jasmonate (MeJA) treatment revealed that NaSGT1 is important for the normal regulation of MeJA-induced transcriptional responses. • This work demonstrates the importance of SGT1 in the regulatory network that deploys defense responses against herbivores, and highlights the significance of SGT1 in plants' responses to JA.

  17. Jasmonic Acid Modulates the Physio-Biochemical Attributes, Antioxidant Enzyme Activity, and Gene Expression in Glycine max under Nickel Toxicity

    PubMed Central

    Sirhindi, Geetika; Mir, Mudaser Ahmad; Abd-Allah, Elsayed Fathi; Ahmad, Parvaiz; Gucel, Salih

    2016-01-01

    In present study, we evaluated the effects of Jasmonic acid (JA) on physio-biochemical attributes, antioxidant enzyme activity, and gene expression in soybean (Glycine max L.) plants subjected to nickel (Ni) stress. Ni stress decreases the shoot and root length and chlorophyll content by 37.23, 38.31, and 39.21%, respectively, over the control. However, application of JA was found to improve the chlorophyll content and length of shoot and root of Ni-fed seedlings. Plants supplemented with JA restores the chlorophyll fluorescence, which was disturbed by Ni stress. The present study demonstrated increase in proline, glycinebetaine, total protein, and total soluble sugar (TSS) by 33.09, 51.26, 22.58, and 49.15%, respectively, under Ni toxicity over the control. Addition of JA to Ni stressed plants further enhanced the above parameters. Ni stress increases hydrogen peroxide (H2O2) by 68.49%, lipid peroxidation (MDA) by 50.57% and NADPH oxidase by 50.92% over the control. Supplementation of JA minimizes the accumulation of H2O2, MDA, and NADPH oxidase, which helps in stabilization of biomolecules. The activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) increases by 40.04, 28.22, 48.53, and 56.79%, respectively, over the control in Ni treated seedlings and further enhancement in the antioxidant activity was observed by the application of JA. Ni treated soybean seedlings showed increase in expression of Fe-SOD by 77.62, CAT by 15.25, POD by 58.33, and APX by 80.58% over the control. Nevertheless, application of JA further enhanced the expression of the above genes in the present study. Our results signified that Ni stress caused negative impacts on soybean seedlings, but, co-application of JA facilitate the seedlings to combat the detrimental effects of Ni through enhanced osmolytes, activity of antioxidant enzymes and gene expression. PMID:27242811

  18. Normal phase LC coupled with direct analysis in real time MS for the chiral analysis of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and jasmonic acid.

    PubMed

    Chang, Cuilan; Zhou, Zhigui; Yang, Youyou; Han, Yehua; Bai, Yu; Zhao, Meiping; Liu, Huwei

    2012-11-01

    Normal phase chiral LC (NPLC) has been proved to be powerful and efficient for chiral separation. However, the combination of NPLC with ESI or atmospheric pressure chemical ionization MS is restricted by the poor ionization efficiency and thermal fragmentations of analytes to some extent. Direct analysis in real time MS (DART-MS) is an ambient ionization technique that shows high ionization efficiency of the analytes in the normal phase mobile phase. In this work, we coupled chiral NPLC to DART-MS for the chiral qualitative and quantitative analysis of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and jasmonic acid enantiomers. Satisfactory results for the enantiomers of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol operating in the positive mode were obtained in terms of linearity (2.5-250 μg/mL, R(2) , 0.999-1.000) and repeatability (25 μg/mL, RSDs, 4.7-5.6%). Moreover, chiral NPLC-DART-MS resulted in the simultaneous chiral separation and detection of jasmonic acid enantiomers, which are very difficult to be analyzed by NPLC-ESI-MS and NPLC-APCI-MS. Compared with the coupled techniques of NPLC-ESI-MS and NPLC-APCI-MS, NPLC-DART-MS showed advantages in increasing the ionization efficiency and reducing the in-source thermal fragmentation of analytes.

  19. T3SS-dependent differential modulations of the jasmonic acid pathway in susceptible and resistant genotypes of Malus spp. challenged with Erwinia amylovora.

    PubMed

    Dugé De Bernonville, Thomas; Gaucher, Matthieu; Flors, Victor; Gaillard, Sylvain; Paulin, Jean-Pierre; Dat, James F; Brisset, Marie-Noëlle

    2012-06-01

    Fire blight is a bacterial disease of Maloideae caused by Erwinia amylovora (Ea). This necrogenic enterobacterium uses a type III secretion system (T3SS) to inject type III effectors into the plant cells to cause disease on its susceptible hosts, including economically important crops like apple and pear. The expressions of marker genes of the salicylic acid (SA) and jasmonic acid (JA) defense regulation pathways were monitored by RT-qPCR in leaves of two apple genotypes, one susceptible and one resistant, challenged with a wild type strain, a T3SS-deficient strain or water. The transcriptional data taken together with hormone level measurements indicated that the SA pathway was similarly induced in both apple genotypes during infection by Ea. On the contrary, the data clearly showed a strong T3SS-dependent down-regulation of the JA pathway in leaves of the susceptible genotype but not in those of the resistant one. Accordingly, methyl-jasmonate treated susceptible plants displayed an increased resistance to Ea. Bacterial mutant analysis indicated that JA manipulation by Ea mainly relies on the type III effector DspA/E. Taken together, our data suggest that the T3SS-dependent down-regulation of the JA pathway is a critical step in the infection process of Malus spp. by Ea.

  20. The platelet-activating factor acetylhydrolase gene derived from Trichoderma harzianum induces maize resistance to Curvularia lunata through the jasmonic acid signaling pathway.

    PubMed

    Yu, Chuanjin; Fan, Lili; Gao, Jinxin; Wang, Meng; Wu, Qiong; Tang, Jun; Li, Yaqian; Chen, Jie

    2015-01-01

    Platelet-activating factor acetylhydrolase (PAF-AH) derived from Trichoderma harzianum was upregulated by the interaction of T. harzianum with maize roots or the foliar pathogen Curvularia lunata. PAF-AH was associated with chitinase and cellulase expressions, but especially with chitinase, because its activity in the KO40 transformant (PAF-AH disruption transformant) was lower, compared with the wild-type strain T28. The result demonstrated that the colonization of maize roots by T. harzianum induced systemic protection of leaves inoculated with C. lunata. Such protection was associated with the expression of inducible jasmonic acid pathway-related genes. Moreover, the data from liquid chromatography-mass spectrometry confirmed that the concentration of jasmonic acid in maize leaves was associated with the expression level of defense-related genes, suggesting that PAF-AH induced resistance to the foliar pathogen. Our findings showed that PAF-AH had an important function in inducing systemic resistance to maize leaf spot pathogen.

  1. Identification of Jasmonic Acid and Jasmonoyl-Isoleucine, and Characterization of AOS, AOC, OPR and JAR1 in the Model Lycophyte Selaginella moellendorffii.

    PubMed

    Pratiwi, Putri; Tanaka, Genta; Takahashi, Tomohiro; Xie, Xiaonan; Yoneyama, Koichi; Matsuura, Hideyuki; Takahashi, Kosaku

    2017-03-13

    Jasmonic acid (JA) is involved in a variety of physiological responses in seed plants. However, the detection and role of JA in lycophytes, a group of seedless vascular plants, have remained elusive until recently. This study provides the first evidence of 12-oxo-phytodienoic acid (OPDA), JA and jasmonoyl-isoleucine (JA-Ile) in the model lycophyte Selaginella moellendorffii. Mechanical wounding stimulated the accumulation of OPDA, JA and JA-Ile. These data were corroborated by the detection of enzymatically active allene oxide synthase (AOS), allene oxide cyclase (AOC), 12-oxo-phytodienoic acid reductase 3 (OPR3) and JA-Ile synthase (JAR1) in S. moellendorffii. SmAOS2 is involved in the first committed step of JA biosynthesis. SmAOC1 is a crucial enzyme for generating the basic structure of jasmonates and is actively involved in the formation of OPDA. SmOPR5, a functionally active OPR3-like enzyme, is also vital for the reduction of (+)-cis-OPDA, the only isomer of the JA precursor. The conjugation of JA to Ile by SmJAR1 demonstrates that S. moellendorffii produces JA-Ile. Thus, the four active enzymes have characteristics similar to those in seed plants. Wounding and JA treatment induced the expression of SmAOC1 and SmOPR5. Furthermore, JA inhibited the growth of shoots in S. moellendorffii, which suggests that JA functions as a signaling molecule in S. moellendorffii. This study proposes that JA evolved as a plant hormone for stress adaptation, beginning with the emergence of vascular plants.

  2. Priming of seeds with methyl jasmonate induced resistance to hemi-biotroph Fusarium oxysporum f.sp. lycopersici in tomato via 12-oxo-phytodienoic acid, salicylic acid, and flavonol accumulation.

    PubMed

    Król, P; Igielski, R; Pollmann, S; Kępczyńska, E

    2015-05-01

    Methyl jasmonate (MeJA) was tested by seed treatment for its ability to protect tomato seedlings against fusarium wilt caused by the soil-borne fungal pathogen Fusarium oxysporum f.sp. lycopersici. Isolated from Solanum lycopersicon L. seeds, cv. Beta fungus was identified as F. oxysporum f.sp. lycopersici Race 3 fungus by using phytopathological and molecular methods. MeJA applied at 0.01, 0.1 and 1 mM reduced spore germination and mycelial growth in vitro. Soaking of tomato seeds in MeJA solution at 0.1 mM for 1 h significantly enhanced the resistance level against the tested fungus in tomato seedlings 4 weeks after inoculation. The extracts from leaves of 15-day-old seedlings obtained from previously MeJA soaked seeds had the ability to inhibit in vitro spore germination of tested fungus. In these seedlings a significant increase in the levels phenolic compounds such as salicylic acid (SA), kaempferol and quercetin was observed. Up-regulation of phenylalanine ammonia-lyase (PAL5) and benzoic acid/salicylic acid carboxyl methyltransferase (BSMT) genes and down-regulation of the isochorysmate synthase (ICS) gene in response to exogenous MeJA application indicate that the phenylalanine ammonia-lyase (PAL), not the isochorismate (IC) pathway, is the primary route for SA production in tomato. Moreover, the increased accumulation of the flavonols quercetin and kaempferol appears closely related to the increase of PAL5, chalcone synthase (CHS) and flavonol synthase/flavanone 3-hydroxylase-like (FLS) genes. Elevated levels of salicylic acid in seedlings raised from MeJA-soaked seeds were simultaneously accompanied by a decrease of jasmonic acid, the precursor of MeJA, and an increase of 12-oxo-phytodienoic acid (OPDA), the precursor of jasmonic acid. The present results indicate that the priming of tomato seeds with 0.1mM MeJA before sowing enables the seedlings grown from these seeds to reduce the attack of the soil-borne fungal pathogen F. oxysporum f.sp. lycopersici

  3. Nicotiana attenuata SIPK, WIPK, NPR1, and Fatty Acid-Amino Acid Conjugates Participate in the Induction of Jasmonic Acid Biosynthesis by Affecting Early Enzymatic Steps in the Pathway1[W][OA

    PubMed Central

    Kallenbach, Mario; Alagna, Fiammetta; Baldwin, Ian Thomas; Bonaventure, Gustavo

    2010-01-01

    Wounding and herbivore attack elicit the rapid (within minutes) accumulation of jasmonic acid (JA) that results from the activation of previously synthesized biosynthetic enzymes. Recently, several regulatory factors that affect JA production have been identified; however, how these regulators affect JA biosynthesis remains at present unknown. Here we demonstrate that Nicotiana attenuata salicylate-induced protein kinase (SIPK), wound-induced protein kinase (WIPK), nonexpressor of PR-1 (NPR1), and the insect elicitor N-linolenoyl-glucose (18:3-Glu) participate in mechanisms affecting early enzymatic steps of the JA biosynthesis pathway. Plants silenced in the expression of SIPK and NPR1 were affected in the initial accumulation of 13-hydroperoxy-linolenic acid (13-OOH-18:3) after wounding and 18:3-Glu elicitation by mechanisms independent of changes in 13-lipoxygenase activity. Moreover, 18:3-Glu elicited an enhanced and rapid accumulation of 13-OOH-18:3 that depended partially on SIPK and NPR1 but was independent of increased 13-lipoxygenase activity. Together, the results suggested that substrate supply for JA production was altered by 18:3-Glu elicitation and SIPK- and NPR1-mediated mechanisms. Consistent with a regulation at the level of substrate supply, we demonstrated by virus-induced gene silencing that a wound-repressed plastidial glycerolipase (NaGLA1) plays an essential role in the induction of de novo JA biosynthesis. In contrast to SIPK and NPR1, mechanisms mediated by WIPK did not affect the production of 13-OOH-18:3 but were critical to control the conversion of this precursor into 12-oxo-phytodienoic acid. These differences could be partially accounted for by reduced allene oxide synthase activity in WIPK-silenced plants. PMID:19897603

  4. Effect of jasmonic acid-methyl ester on the composition of carbohydrates and germination of yellow lupine (Lupinus luteus L.) seeds.

    PubMed

    Zalewski, Kazimierz; Nitkiewicz, Bartosz; Lahuta, Lesław B; Głowacka, Katarzyna; Socha, Aleksander; Amarowicz, Ryszard

    2010-08-15

    Mature seeds of yellow lupine contained sucrose, raffinose family oligosaccharides (RFOs), and galactosyl cyclitols as major soluble carbohydrates. The study showed that RFOs dominated in lupine seeds (16% DW). The disappearance of both types of alpha-d-galactosides in germinating lupine seeds was strongly inhibited by the presence of jasmonic acid-methyl ester (JA-Me) at a concentration of 10(-3)M in the incubation medium. JA-Me inhibited the activity of alpha-D-galactosidase (fraction I) during seed germination. Anatomical studies of lupine roots have shown certain cell structure differences between control and JA-Me-treated seedlings. The cross-sections of plant roots treated with JA-Me showed a characteristic folding of the cell walls in all root tissues, starting from the rhyzodermis, cortex and vascular cylinder. In water-treated (control) plants, the cell walls were rounded with no folding.

  5. Effect of jasmonic acid elicitation on the yield, chemical composition, and antioxidant and anti-inflammatory properties of essential oil of lettuce leaf basil (Ocimum basilicum L.).

    PubMed

    Złotek, Urszula; Michalak-Majewska, Monika; Szymanowska, Urszula

    2016-12-15

    The effect of elicitation with jasmonic acid (JA) on the plant yield, the production and composition of essential oils of lettuce leaf basil was evaluated. JA-elicitation slightly affected the yield of plants and significantly increased the amount of essential oils produced by basil - the highest oil yield (0.78±0.005mL/100gdw) was achieved in plants elicited with 100μM JA. The application of the tested elicitor also influenced the chemical composition of basil essential oils - 100μM JA increased the linalool, eugenol, and limonene levels, while 1μM JA caused the highest increase in the methyl eugenol content. Essential oils from JA-elicited basil (especially 1μM and 100μM) exhibited more effective antioxidant and anti-inflammatory potential; therefore, this inducer may be a very useful biochemical tool for improving production and composition of herbal essential oils.

  6. [The participation of salicylic and jasmonic acids in genetic and induced resistance of tomato to Meloidogyne incognita (Kofoid and White, 1919)].

    PubMed

    Zinov'eva, S V; Vasiukova, N I; Udalova, Zh V; Gerasimova, N G

    2013-01-01

    Salicylic (SA) and jasmonic (JA) acids are the best known mediators of signal systems in plants. In this investigation the participation and character of interactions between SA- and JA-signals under the induced and genetic resistance of plants to nematodes was investigated on the model system tomato (Lycopersicon esculentum) and the root-knot nematode Meloidogyne incognita. This study demonstrates that application of JA and SA to tomato foliage induces systemic effects that suppress root-knot nematode infestation, inhibition of nematode reproduction, and also increased activity of LOX and PAL, the enzymes of biosynthesis of JA and SA. JA treatment did not inhibit Mz-mediated resistance, which suggests a lack of signaling conflicts between these two forms of defense.

  7. Leaf and root glucosinolate profiles of Chinese cabbage (Brassica rapa ssp. pekinensis) as a systemic response to methyl jasmonate and salicylic acid elicitation.

    PubMed

    Zang, Yun-xiang; Ge, Jia-li; Huang, Ling-hui; Gao, Fei; Lv, Xi-shan; Zheng, Wei-wei; Hong, Seung-beom; Zhu, Zhu-jun

    2015-08-01

    Glucosinolates (GSs) are an important group of defensive phytochemicals mainly found in Brassicaceae. Plant hormones jasmonic acid (JA) and salicylic acid (SA) are major regulators of plant response to pathogen attack. However, there is little information about the interactive effect of both elicitors on inducing GS biosynthesis in Chinese cabbage (Brassica rapa ssp. pekinensis). In this study, we applied different concentrations of methyl jasmonate (MeJA) and/or SA onto the leaf and root of Chinese cabbage to investigate the time-course interactive profiles of GSs. Regardless of the site of the elicitation and the concentrations of the elicitors, the roots accumulated much more GSs and were more sensitive and more rapidly responsive to the elicitors than leaves. Irrespective of the elicitation site, MeJA had a greater inducing and longer lasting effect on GS accumulation than SA. All three components of indole GS (IGS) were detected along with aliphatic and aromatic GSs. However, IGS was a major component of total GSs that accumulated rapidly in both root and leaf tissues in response to MeJA and SA elicitation. Neoglucobrassicin (neoGBC) did not respond to SA but to MeJA in leaf tissue, while it responded to both SA and MeJA in root tissue. Conversion of glucobrassicin (GBC) to neoGBC occurred at a steady rate over 3 d of elicitation. Increased accumulation of 4-methoxy glucobrassicin (4-MGBC) occurred only in the root irrespective of the type of elicitors and the site of elicitation. Thus, accumulation of IGS is a major metabolic hallmark of SA- and MeJA-mediated systemic response systems. SA exerted an antagonistic effect on the MeJA-induced root GSs irrespective of the site of elicitation. However, SA showed synergistic and antagonistic effects on the MeJA-induced leaf GSs when roots and leaves are elicitated for 3 d, respectively.

  8. Salicylic and jasmonic acid pathways are necessary for defence against Dickeya solani as revealed by a novel method for Blackleg disease screening of in vitro grown potato.

    PubMed

    Burra, D D; Mühlenbock, P; Andreasson, E

    2015-09-01

    Potato is major crop ensuring food security in Europe, and blackleg disease is increasingly causing losses in yield and during storage. Recently, one blackleg pathogen, Dickeya solani has been shown to be spreading in Northern Europe that causes aggressive disease development. Currently, identification of tolerant commercial potato varieties has been unsuccessful; this is confounded by the complicated etiology of the disease and a strong environmental influence on disease development. There is currently a lack of efficient testing systems. Here, we describe a system for quantification of blackleg symptoms on shoots of sterile in vitro potato plants, which saves time and space compared to greenhouse and existing field assays. We found no evidence for differences in infection between the described in vitro-based screening method and existing greenhouse assays. This system facilitates efficient screening of blackleg disease response of potato plants independent of other microorganisms and variable environmental conditions. We therefore used the in vitro screening method to increase understanding of plant mechanisms involved in blackleg disease development by analysing disease response of hormone- related (salicylic and jasmonic acid) transgenic potato plants. We show that both jasmonic (JA) and salicylic (SA) acid pathways regulate tolerance to blackleg disease in potato, a result unlike previous findings in Arabidopsis defence response to necrotrophic bacteria. We confirm this by showing induction of a SA marker, pathogenesis-related protein 1 (StPR1), and a JA marker, lipoxygenase (StLOX), in Dickeya solani infected in vitro potato plants. We also observed that tubers of transgenic potato plants were more susceptible to soft rot compared to wild type, suggesting a role for SA and JA pathways in general tolerance to Dickeya.

  9. Methyl jasmonate induces lauric acid omega-hydroxylase activity and accumulation of CYP94A1 transcripts but does not affect epoxide hydrolase activities in vicia sativa seedlings

    PubMed

    Pinot; Benveniste; Sala n JP; Durst

    1998-12-01

    Treatment of etiolated Vicia sativa seedlings by the plant hormone methyl jasmonate (MetJA) led to an increase of cytochrome P450 content. Seedlings that were treated for 48 h in a 1 mM solution of MetJA stimulated omega-hydroxylation of 12:0 (lauric acid) 14-fold compared with the control (153 versus 11 pmol min-1 mg-1 protein, respectively). Induction was dose dependent. The increase of activity (2.7-fold) was already detectable after 3 h of treatment. Activity increased as a function of time and reached a steady level after 24 h. Northern-blot analysis revealed that the transcripts coding for CYP94A1, a fatty acid omega-hydroxylase, had already accumulated after 1 h of exposure to MetJA and was maximal between 3 and 6 h. Under the same conditions, a study of the enzymatic hydrolysis of 9,10-epoxystearic acid showed that both microsomal and soluble epoxide hydrolase activities were not affected by MetJA treatment.

  10. Promoter analyses and transcriptional profiling of eggplant polyphenol oxidase 1 gene (SmePPO1) reveal differential response to exogenous methyl jasmonate and salicylic acid.

    PubMed

    Shetty, Santoshkumar M; Chandrashekar, Arun; Venkatesh, Yeldur P

    2012-05-01

    The transcriptional regulation of multigenic eggplant (Solanum melongena) polyphenol oxidase genes (SmePPO) is orchestrated by their corresponding promoters which mediate developmentally regulated expression in response to myriad biotic and abiotic factors. However, information on structural features of SmePPO promoters and modulation of their expression by plant defense signals are lacking. In the present study, SmePPOPROMOTERs were cloned by genome walking, and their transcription start sites (TSS) were determined by RLM-RACE. Extensive sequence analyses revealed the presence of evolutionarily conserved and over-represented putative cis-acting elements involved in light-regulated transcription, biosynthetic pathways (phenylpropanoid/flavonoid), hormone signaling (abscisic acid, gibberellic acid, jasmonate and salicylate), elicitor and stress responses (cold/dehydration responses), sugar metabolism and plant defense signaling (W-BOX/WRKY) that are common to SmePPOPROMOTER1 and 2. The TSS for SmePPO genes are located 9-15bp upstream of ATG with variable lengths of 5' untranslated regions. Transcriptional profiling of SmePPOs in eggplant seedlings has indicated differential response to methyl jasmonate (MeJA) or salicylic acid (SA) treatment. In planta, while MeJA elicited expression of all the six SmePPOs, SA was only able to induce the expression of SmePPO4-6. Interestingly, in dual treatment, SA considerably repressed the MeJA-induced expression of SmePPOs. Functional dissection of SmePPOPROMOTER1 by deletion analyses using Agrobacterium-mediated transient expression in tobacco leaves has shown that MeJA enhances the SmePPOPROMOTER1-β-glucuronidase (GUS) expression in vivo, while SA does not. Histochemical and quantitative GUS assays have also indicated the negative effect of SA on MeJA-induced expression of SmePPOPROMOTER1. By combining in silico analyses, transcriptional profiling and expression of SmePPOPROMOTER1-GUS fusions, the role of SA on the modulation

  11. RepA Protein Encoded by Oat dwarf virus Elicits a Temperature-Sensitive Hypersensitive Response-Type Cell Death That Involves Jasmonic Acid-Dependent Signaling.

    PubMed

    Qian, Yajuan; Hou, Huwei; Shen, Qingtang; Cai, Xinzhong; Sunter, Garry; Zhou, Xueping

    2016-01-01

    The hypersensitive response (HR) is a component of disease resistance that is often induced by pathogen infection, but essentially no information is available for members of the destructive mastreviruses. We have investigated an HR-type response elicited in Nicotiana species by Oat dwarf virus (ODV) and have found that expression of the ODV RepA protein but not other ODV-encoded proteins elicits the HR-type cell death associated with a burst of H2O2. Deletion mutagenesis indicates that the first nine amino acids (aa) at the N terminus of RepA and the two regions located between aa residues 173 and 195 and between aa residues 241 and 260 near the C terminus are essential for HR-type cell-death elicitation. Confocal and electron microscopy showed that the RepA protein is localized in the nuclei of plant cells and might contain bipartite nuclear localization signals. The HR-like lesions mediated by RepA were inhibited by temperatures above 30°C and involvement of jasmonic acid (JA) in HR was identified by gain- and loss-of-function experiments. To our knowledge, this is the first report of an elicitor of HR-type cell death from mastreviruses.

  12. Intronic T-DNA Insertion Renders Arabidopsis opr3 a Conditional Jasmonic Acid-Producing Mutant1[C][W][OA

    PubMed Central

    Chehab, E. Wassim; Kim, Se; Savchenko, Tatyana; Kliebenstein, Daniel; Dehesh, Katayoon; Braam, Janet

    2011-01-01

    Jasmonic acid and its derived metabolites (JAs) orchestrate plant defense against insects and fungi. 12-Oxo-phytodienoic acid (OPDA), a JA precursor, has also been implicated in plant defense. We sought to define JAs and OPDA functions through comparative defense susceptibility characteristics of three Arabidopsis (Arabidopsis thaliana) genotypes: aos, lacking JAs and OPDA; opda reductase3 (opr3), deficient in JA production but can accumulate OPDA; and transgenics that overexpress OPR3. opr3, like aos, is susceptible to cabbage loopers (Trichoplusia ni) but, relative to aos, opr3 has enhanced resistance to a necrotrophic fungus. Gas chromatography-mass spectrometry reveals that opr3 produces OPDA but no detectable JAs following wounding and looper infestation; unexpectedly, substantial levels of JAs accumulate in opr3 upon fungal infection. Full-length OPR3 transcripts accumulate in fungal-infected opr3, potentially through splicing of the T-DNA containing intron. Fungal resistance correlates with levels of JAs not OPDA; therefore, opr3 resistance to some pests is likely due to JA accumulation, and signaling activities ascribed to OPDA should be reassessed because opr3 can produce JAs. Together these data (1) reinforce the primary role JAs play in plant defense against insects and necrotrophic fungi, (2) argue for a reassessment of signaling activities ascribed to OPDA, and (3) provide evidence that mutants with intron insertions can retain gene function. PMID:21487047

  13. Disruption of OPR7 and OPR8 Reveals the Versatile Functions of Jasmonic Acid in Maize Development and Defense[W

    PubMed Central

    Yan, Yuanxin; Christensen, Shawn; Isakeit, Tom; Engelberth, Jürgen; Meeley, Robert; Hayward, Allison; Emery, R.J. Neil; Kolomiets, Michael V.

    2012-01-01

    Here, multiple functions of jasmonic acid (JA) in maize (Zea mays) are revealed by comprehensive analyses of JA-deficient mutants of the two oxo-phytodienoate reductase genes, OPR7 and OPR8. Single mutants produce wild-type levels of JA in most tissues, but the double mutant opr7 opr8 has dramatically reduced JA in all organs tested. opr7 opr8 displayed strong developmental defects, including formation of a feminized tassel, initiation of female reproductive buds at each node, and extreme elongation of ear shanks; these defects were rescued by exogenous JA. These data provide evidence that JA is required for male sex determination and suppression of female reproductive organ biogenesis. Moreover, opr7 opr8 exhibited delayed leaf senescence accompanied by reduced ethylene and abscisic acid levels and lack of anthocyanin pigmentation of brace roots. Remarkably, opr7 opr8 is nonviable in nonsterile soil and under field conditions due to extreme susceptibility to a root-rotting oomycete (Pythium spp), demonstrating that these genes are necessary for maize survival in nature. Supporting the importance of JA in insect defense, opr7 opr8 is susceptible to beet armyworm. Overall, this study provides strong genetic evidence for the global roles of JA in maize development and immunity to pathogens and insects. PMID:22523204

  14. The role of glucosinolates and the jasmonic acid pathway in resistance of Arabidopsis thaliana against molluskan herbivores

    PubMed Central

    Bodenhausen, Natacha; Schramm, Katharina; Paetz, Christian; Vassão, Daniel Giddings; Reichelt, Michael; von Knorre, Dietrich; Bergelson, Joy; Erb, Matthias; Gershenzon, Jonathan

    2016-01-01

    Although slugs and snails play important roles in terrestrial ecosystems and cause considerable damage on a variety of crop plants, knowledge about the mechanisms of plant immunity to mollusks is limited. We found slugs to be natural herbivores of Arabidopsis thaliana and therefore investigated possible resistance mechanisms of this species against several molluskan herbivores. Treating wounded leaves with the mucus residue (“slime trail”) of the Spanish slug Arion lusitanicus increased wound-induced jasmonate levels, suggesting the presence of defense elicitors in the mucus. Plants deficient in jasmonate biosynthesis and signaling suffered more damage by molluskan herbivores in the laboratory and in the field, demonstrating that JA-mediated defenses protect A. thaliana against slugs and snails. Furthermore, experiments using A. thaliana mutants with altered levels of specific glucosinolate classes revealed the importance of aliphatic glucosinolates in defending leaves and reproductive structures against mollusks. The presence in mollusk feces of known and novel metabolites arising from glutathione conjugation with glucosinolate hydrolysis products suggests that molluskan herbivores actively detoxify glucosinolates. Higher levels of aliphatic glucosinolates were found in plants during the night compared to the day, which correlated well with the nocturnal activity rhythms of slugs and snails. Our data highlight the function of well-known anti-herbivore defense pathways in resistance against slugs and snails and suggest an important role for the diurnal regulation of defense metabolites against nocturnal molluskan herbivores. PMID:24313595

  15. The role of glucosinolates and the jasmonic acid pathway in resistance of Arabidopsis thaliana against molluscan herbivores.

    PubMed

    Falk, Kimberly L; Kästner, Julia; Bodenhausen, Natacha; Schramm, Katharina; Paetz, Christian; Vassão, Daniel G; Reichelt, Michael; von Knorre, Dietrich; Bergelson, Joy; Erb, Matthias; Gershenzon, Jonathan; Meldau, Stefan

    2014-03-01

    Although slugs and snails play important roles in terrestrial ecosystems and cause considerable damage on a variety of crop plants, knowledge about the mechanisms of plant immunity to molluscs is limited. We found slugs to be natural herbivores of Arabidopsis thaliana and therefore investigated possible resistance mechanisms of this species against several molluscan herbivores. Treating wounded leaves with the mucus residue ('slime trail') of the Spanish slug Arion lusitanicus increased wound-induced jasmonate levels, suggesting the presence of defence elicitors in the mucus. Plants deficient in jasmonate biosynthesis and signalling suffered more damage by molluscan herbivores in the laboratory and in the field, demonstrating that JA-mediated defences protect A. thaliana against slugs and snails. Furthermore, experiments using A. thaliana mutants with altered levels of specific glucosinolate classes revealed the importance of aliphatic glucosinolates in defending leaves and reproductive structures against molluscs. The presence in mollusc faeces of known and novel metabolites arising from glutathione conjugation with glucosinolate hydrolysis products suggests that molluscan herbivores actively detoxify glucosinolates. Higher levels of aliphatic glucosinolates were found in plants during the night compared to the day, which correlated well with the nocturnal activity rhythms of slugs and snails. Our data highlight the function of well-known antiherbivore defence pathways in resistance against slugs and snails and suggest an important role for the diurnal regulation of defence metabolites against nocturnal molluscan herbivores.

  16. Jasmonate

    PubMed Central

    Ramel, Fanny; Ksas, Brigitte; Havaux, Michel

    2013-01-01

    Under stress conditions that bring about excessive absorption of light energy in the chloroplasts, the formation of singlet oxygen (1O2) can be strongly enhanced, triggering programmed cell death. However, the 1O2 signaling pathway can also lead to acclimation to photooxidative stress, when 1O2 is produced in relatively low amounts. This acclimatory response is associated with a strong downregulation of the jasmonate biosynthesis pathway and the maintenance of low jasmonate levels, even under high light stress conditions that normally induce jasmonate synthesis. These findings suggest a central role for this phytohormone in the orientation of the 1O2 signaling pathway toward cell death or acclimation. This conclusion is confirmed here in an Arabidopsis double mutant obtained by crossing the 1O2-overproducing mutant ch1 and the jasmonate-deficient mutant dde2. This double mutant was found to be constitutively resistant to 1O2 stress and to display a strongly stimulated growth rate compared with the single ch1 mutant. However, the involvement of other phytohormones, such as ethylene, cannot be excluded. PMID:24103864

  17. Arabidopsis class I and class II TCP transcription factors regulate jasmonic acid metabolism and leaf development antagonistically.

    PubMed

    Danisman, Selahattin; van der Wal, Froukje; Dhondt, Stijn; Waites, Richard; de Folter, Stefan; Bimbo, Andrea; van Dijk, Aalt D J; Muino, Jose M; Cutri, Lucas; Dornelas, Marcelo C; Angenent, Gerco C; Immink, Richard G H

    2012-08-01

    TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR1 (TCP) transcription factors control developmental processes in plants. The 24 TCP transcription factors encoded in the Arabidopsis (Arabidopsis thaliana) genome are divided into two classes, class I and class II TCPs, which are proposed to act antagonistically. We performed a detailed phenotypic analysis of the class I tcp20 mutant, showing an increase in leaf pavement cell sizes in 10-d-old seedlings. Subsequently, a glucocorticoid receptor induction assay was performed, aiming to identify potential target genes of the TCP20 protein during leaf development. The LIPOXYGENASE2 (LOX2) and class I TCP9 genes were identified as TCP20 targets, and binding of TCP20 to their regulatory sequences could be confirmed by chromatin immunoprecipitation analyses. LOX2 encodes for a jasmonate biosynthesis gene, which is also targeted by class II TCP proteins that are under the control of the microRNA JAGGED AND WAVY (JAW), although in an antagonistic manner. Mutation of TCP9, the second identified TCP20 target, resulted in increased pavement cell sizes during early leaf developmental stages. Analysis of senescence in the single tcp9 and tcp20 mutants and the tcp9tcp20 double mutants showed an earlier onset of this process in comparison with wild-type control plants in the double mutant only. Both the cell size and senescence phenotypes are opposite to the known class II TCP mutant phenotype in JAW plants. Altogether, these results point to an antagonistic function of class I and class II TCP proteins in the control of leaf development via the jasmonate signaling pathway.

  18. Synergism in the effect of prior jasmonic acid application on herbivore-induced volatile emission by Lima bean plants: transcription of a monoterpene synthase gene and volatile emission

    PubMed Central

    Menzel, Tila R.; Weldegergis, Berhane T.; David, Anja; Boland, Wilhelm; Gols, Rieta; van Loon, Joop J. A.; Dicke, Marcel

    2014-01-01

    Jasmonic acid (JA) plays a central role in induced plant defence e.g. by regulating the biosynthesis of herbivore-induced plant volatiles that mediate the attraction of natural enemies of herbivores. Moreover, exogenous application of JA can be used to elicit plant defence responses similar to those induced by biting-chewing herbivores and mites that pierce cells and consume their contents. In the present study, we used Lima bean (Phaseolus lunatus) plants to explore how application of a low dose of JA followed by minor herbivory by spider mites (Tetranychus urticae) affects transcript levels of P. lunatus (E)-β-ocimene synthase (PlOS), emission of (E)-β-ocimene and nine other plant volatiles commonly associated with herbivory. Furthermore, we investigated the plant’s phytohormonal response. Application of a low dose of JA increased PlOS transcript levels in a synergistic manner when followed by minor herbivory for both simultaneous and sequential infestation. Emission of (E)-β-ocimene was also increased, and only JA, but not SA, levels were affected by treatments. Projection to latent structures-discriminant analysis (PLS-DA) of other volatiles showed overlap between treatments. Thus, a low-dose JA application results in a synergistic effect on gene transcription and an increased emission of a volatile compound involved in indirect defence after herbivore infestation. PMID:25318119

  19. Endogenous abscisic acid is involved in methyl jasmonate-induced reactive oxygen species and nitric oxide production but not in cytosolic alkalization in Arabidopsis guard cells.

    PubMed

    Ye, Wenxiu; Hossain, Mohammad Anowar; Munemasa, Shintaro; Nakamura, Yoshimasa; Mori, Izumi C; Murata, Yoshiyuki

    2013-09-01

    We recently demonstrated that endogenous abscisic acid (ABA) is involved in methyl jasmonate (MeJA)-induced stomatal closure in Arabidopsis thaliana. In this study, we investigated whether endogenous ABA is involved in MeJA-induced reactive oxygen species (ROS) and nitric oxide (NO) production and cytosolic alkalization in guard cells using an ABA-deficient Arabidopsis mutant, aba2-2, and an inhibitor of ABA biosynthesis, fluridon (FLU). The aba2-2 mutation impaired MeJA-induced ROS and NO production. FLU inhibited MeJA-induced ROS production in wild-type guard cells. Pretreatment with 0.1 μM ABA, which does not induce stomatal closure in the wild type, complemented the insensitivity to MeJA of the aba2-2 mutant. However, MeJA induced cytosolic alkalization in both wild-type and aba2-2 guard cells. These results suggest that endogenous ABA is involved in MeJA-induced ROS and NO production but not in MeJA-induced cytosolic alkalization in Arabidopsis guard cells.

  20. Exogenous polyamines elicit herbivore-induced volatiles in lima bean leaves: involvement of calcium, H2O2 and Jasmonic acid.

    PubMed

    Ozawa, Rika; Bertea, Cinzia M; Foti, Maria; Narayana, Ravishankar; Arimura, Gen-Ichiro; Muroi, Atsushi; Horiuchi, Jun-Ichiro; Nishioka, Takaaki; Maffei, Massimo E; Takabayashi, Junji

    2009-12-01

    We investigated the role of polyamines (PAs) in lima bean (Phaseolus lunatus) leaves on the production of herbivorous mite (Tetranychus urticae)-induced plant volatiles that attract carnivorous natural enemies of the herbivores. To do this, we focused on the effects of the exogenous PAs [cadaverine, putrescine, spermidine and spermine (Spm)] on the production of volatiles, H(2)O(2) and jasmonic acid (JA) and the levels of defensive genes, cytosolic calcium and reactive oxygen species (ROS). Among the tested PAs, Spm was the most active in inducing the production of volatile terpenoids known to be induced by T. urticae. An increase in JA levels was also found after Spm treatment, indicating that Spm induces the biosynthesis of JA, which has been shown elsewhere to regulate the production of some volatile terpenoids. Further, treatment with JA and Spm together resulted in greater volatile emission than that with JA alone. In a Y-tube olfactometer, leaves treated with Spm + JA attracted more predatory mites (Phytoseiulus persimilis) than those treated with JA alone. After treatment with Spm + JA, no effects were found on the enzyme activity of polyamine oxidase and copper amine oxidase. However, induction of calcium influx and ROS production, and increased enzyme activities and gene expression for NADPH oxidase complex, superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase and glutathione peroxidase were found after treatment with Spm + JA. These results indicate that Spm plays an important role in the production of T. urticae-induced lima bean leaf volatiles.

  1. Development of an efficient high-performance thin layer chromatography method for determination of jasmonic acid in leaf tissue of Stevia rebaudiana (Bertoni) Bertoni.

    PubMed

    Kilam, Divya; Saifi, M; Agnihotri, A; Abdin, M Z

    2017-02-13

    Determination of endogenous levels of jasmonic acid (JA) is essential, as it plays a pivotal role in the physiological processes during a plant's life cycle. A high performance thin layer chromatography (HPTLC) method was developed for the detection and quantification of JA in leaf extracts of medicinal plant, Stevia rebaudiana (Bertoni) Bertoni. The separation was achieved using the solvents ethyl acetate-benzene (1:1, v/v) as the mobile phase, followed by scanning and quantification at 295 nm. Densitometric analysis of leaf extract resulted in compact spots for JA at Rf = 0.45 ± 0.02. The linear regression analysis showed good relationship with r value. The recovery rate of JA indicated good reproducibility and repeatability of the assay. The statistical analysis proved the reproducibility of the method; therefore, it can be employed for routine quantification of JA in different tissue samples of S. rebaudiana and may also be extrapolated to other biological samples.

  2. Jasmonic acid treatment to part of the root system is consistent with simulated leaf herbivory, diverting recently assimilated carbon towards untreated roots within an hour.

    PubMed

    Henkes, Gunnar Jakob; Thorpe, Michael R; Minchin, Peter E H; Schurr, Ulrich; Röse, Ursula S R

    2008-09-01

    It is known that shoot application of jasmonic acid (JA) leads to an increased carbon export from leaves to stem and roots, and that root treatment with JA inhibits root growth. Using the radioisotope (11)C, we measured JA effects on carbon partitioning in sterile, split-root, barley plants. JA applied to one root half reduced carbon partitioning to the JA-treated tissue within minutes, whereas the untreated side showed a corresponding--but slower--increase. This response was not observed when instead of applying JA, the sink strength of one root half was reduced by cooling it: there was no enhanced partitioning to the untreated roots. The slower response in the JA-untreated roots, and the difference between the effect of JA and temperature, suggest that root JA treatment caused transduction of a signal from the treated roots to the shoot, leading to an increase in carbon allocation from the leaves to the untreated root tissue, as was indeed observed 10 min after the shoot application of JA. This supports the hypothesis that the response of some plant species to both leaf and root herbivores may be the diversion of resources to safer locations.

  3. Jasmonic acid accumulation and systemic photosynthetic and electrical changes in locally burned wild type tomato, ABA-deficient sitiens mutants and sitiens pre-treated by ABA.

    PubMed

    Hlavinka, Jan; Nožková-Hlaváčková, Vladimíra; Floková, Kristýna; Novák, Ondřej; Nauš, Jan

    2012-05-01

    Burning the terminal leaflet of younger tomato (Lycopersicon esculentum Mill.) leaf caused local and systemic changes in the surface electrical potential (SEP) and gas exchange (GE) parameters. The local and systemic accumulation of endogenous abscisic acid (ABA) and jasmonic acid (JA) was measured 85 min after burning. The experiments were conducted with wild type (WT) plants, ABA-deficient mutant sitiens (SIT) and ABA pre-treated SIT plants (SITA). First changes in SEP were detected within 1.5 min after burning and were followed by a decrease in GE parameters within 3-6 min in WT, SIT and SITA plants. GE and SEP time courses of SIT were different and wave amplitudes of SEP of SIT were lower compared to WT and SITA. ABA content in WT and SITA control plants was similar and substantially higher compared to SIT, JA content was similar among WT, SIT and SITA. While changes in the ABA content in systemic leaves have not been recorded after burning, the systemic JA content was substantially increased in WT and more in SIT and SITA. The results suggest that ABA content governs the systemic reaction of GE and the SEP shape upon local burning. ABA, JA and SEP participate in triggering the GE reaction. The ABA shortage in the SIT in the reaction to burning is partly compensated by an enhanced JA accumulation. This JA compensation is maintained even in SIT endogenously supplied with ABA. A correlation between the systemic JA content and changes in GE parameters or SEP was not found.

  4. Aboveground Whitefly Infestation Modulates Transcriptional Levels of Anthocyanin Biosynthesis and Jasmonic Acid Signaling-Related Genes and Augments the Cope with Drought Stress of Maize

    PubMed Central

    Park, Yong-Soon; Bae, Dong-Won; Ryu, Choong-Min

    2015-01-01

    Up to now, the potential underlying molecular mechanisms by which maize (Zea mays L.) plants elicit defense responses by infestation with a phloem feeding insect whitefly [Bemisia tabaci (Genn.)] have been barely elucidated against (a)biotic stresses. To fill this gap of current knowledge maize plants were infested with whitefly and these plants were subsequently assessed the levels of water loss. To understand the mode of action, plant hormone contents and the stress-related mRNA expression were evaluated. Whitefly-infested maize plants did not display any significant phenotypic differences in above-ground tissues (infested site) compared with controls. By contrast, root (systemic tissue) biomass was increased by 2-fold by whitefly infestation. The levels of endogenous indole-3-acetic acid (IAA), jasmonic acid (JA), and hydrogen peroxide (H2O2) were significantly higher in whitefly-infested plants. The biosynthetic or signaling-related genes for JA and anthocyanins were highly up-regulated. Additionally, we found that healthier plants were obtained in whitefly-infested plants under drought conditions. The weight of whitefly-infested plants was approximately 20% higher than that of control plants at 14 d of drought treatment. The drought tolerance-related genes, ZmbZIP72, ZmSNAC1, and ZmABA1, were highly expressed in the whitefly-infected plants. Collectively, our results suggest that IAA/JA-derived maize physiological changes and correlation of H2O2 production and water loss are modulated by above-ground whitefly infestation in maize plants. PMID:26630288

  5. Chestnut species and jasmonic acid treatment influence development and community interactions of galls produced by the Asian chestnut gall wasp, Dryocosmus kuriphilus.

    PubMed

    Cooper, William R; Rieske, Lynne K

    2011-01-01

    Jasmonic acid (JA) is a plant-signaling hormone involved in defenses against insects and pathogens as well as the regulation of nutrient partitioning. Gall wasps (Hymenoptera: Cynipidae) induce the formation of galls on their host plants, which house immature wasps and provide them with nutrition and protection. The goal of this study was to investigate the effects of JA application on gall development and defenses. Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae) galls on American chestnut, Castanea dentata (Marsh.) Borkhausen (Fagales: Fagaceae), and Chinese chestnut, C. mollissima Blume, were treated with JA or a JA- inhibitor, diethyldithiocarbamic acid (DIECA), to determine the effects of these treatments on gall characteristics and defenses. Chinese chestnut galls treated with JA had greater volume and dry weight, thicker sclerenchyma layers, and fewer external fungal lesions compared with controls. Galls from both chestnut species treated with JA contained a lower proportion of empty chambers, and elevated tannin levels compared with controls. The effects of DIECA on galls were generally opposite from those of JA. American chestnut galls treated with DIECA had lower dry weight and fewer feeding punctures caused by the lesser chestnut weevil compared with controls. Galls from both chestnut species that were treated with DIECA were smaller and had more external fungal lesions compared with controls. Compared to American chestnut galls, Chinese chestnut galls had increased parasitism rates and fewer gall wasps. This study is the first to investigate the effects of JA on an insect gall, and indicates that JA treatments benefit gall wasps by increasing gall size and defenses.

  6. Aboveground Whitefly Infestation Modulates Transcriptional Levels of Anthocyanin Biosynthesis and Jasmonic Acid Signaling-Related Genes and Augments the Cope with Drought Stress of Maize.

    PubMed

    Park, Yong-Soon; Bae, Dong-Won; Ryu, Choong-Min

    2015-01-01

    Up to now, the potential underlying molecular mechanisms by which maize (Zea mays L.) plants elicit defense responses by infestation with a phloem feeding insect whitefly [Bemisia tabaci (Genn.)] have been barely elucidated against (a)biotic stresses. To fill this gap of current knowledge maize plants were infested with whitefly and these plants were subsequently assessed the levels of water loss. To understand the mode of action, plant hormone contents and the stress-related mRNA expression were evaluated. Whitefly-infested maize plants did not display any significant phenotypic differences in above-ground tissues (infested site) compared with controls. By contrast, root (systemic tissue) biomass was increased by 2-fold by whitefly infestation. The levels of endogenous indole-3-acetic acid (IAA), jasmonic acid (JA), and hydrogen peroxide (H2O2) were significantly higher in whitefly-infested plants. The biosynthetic or signaling-related genes for JA and anthocyanins were highly up-regulated. Additionally, we found that healthier plants were obtained in whitefly-infested plants under drought conditions. The weight of whitefly-infested plants was approximately 20% higher than that of control plants at 14 d of drought treatment. The drought tolerance-related genes, ZmbZIP72, ZmSNAC1, and ZmABA1, were highly expressed in the whitefly-infected plants. Collectively, our results suggest that IAA/JA-derived maize physiological changes and correlation of H2O2 production and water loss are modulated by above-ground whitefly infestation in maize plants.

  7. Allantoin, a stress-related purine metabolite, can activate jasmonate signaling in a MYC2-regulated and abscisic acid-dependent manner

    PubMed Central

    Takagi, Hiroshi; Ishiga, Yasuhiro; Watanabe, Shunsuke; Konishi, Tomokazu; Egusa, Mayumi; Akiyoshi, Nobuhiro; Matsuura, Takakazu; Mori, Izumi C.; Hirayama, Takashi; Kaminaka, Hironori; Shimada, Hiroshi; Sakamoto, Atsushi

    2016-01-01

    Allantoin is a metabolic intermediate of purine catabolism that often accumulates in stressed plants. Recently, we used Arabidopsis knockout mutants (aln) of ALLANTOINASE to show that this purine metabolite activates abscisic acid (ABA) production, thereby stimulating stress-related gene expression and enhancing seedling tolerance to abiotic stress. A detailed re-examination of the microarray data of an aln mutant (aln-1) confirmed the increased expression of ABA-related genes and also revealed altered expression of genes involved in jasmonic acid (JA) responses, probably under the control of MYC2, a master switch in the JA signaling pathway. Consistent with the transcriptome profiles, the aln-1 mutant displayed increased JA levels and enhanced responses to mechanical wounding and exogenous JA. Moreover, aln mutants demonstrated modestly increased susceptibility to Pseudomonas syringae and Pectobacterium carotovorum, probably reflecting the antagonistic action of MYC2 on the defense against these bacterial phytopathogens. Exogenously administered allantoin elicited the expression of JA-responsive genes, including MYC2, in wild-type plants, supporting the idea that allantoin might be responsible for the observed JA-related phenotypes of aln mutants. However, mutants deficient in bioactive JA (jar1-1), insensitive to JA (myc2-3), or deficient in ABA (aba2-1 and bglu18) suppressed the effect of exogenous allantoin. The suppression was further confirmed in aln-1 jar1-1 and aln-1 bglu18 double mutants. These results indicate that allantoin can activate the MYC2-regulated JA signaling pathway through ABA production. Overall, this study suggests a possible connection of purine catabolism with stress hormone homeostasis and signaling, and highlights the potential importance of allantoin in these interactions. PMID:26931169

  8. Expression profiles of genes involved in jasmonic acid biosynthesis and signaling during growth and development of carrot.

    PubMed

    Wang, Guanglong; Huang, Wei; Li, Mengyao; Xu, Zhisheng; Wang, Feng; Xiong, Aisheng

    2016-09-01

    Jasmonates (JAs) are recognized as essential regulators in response to environmental stimuli and plant development. Carrot is an Apiaceae vegetable with great value and undergoes significant size changes over the course of plant growth. However, JA accumulation and its potential roles in carrot growth remain unclear. Here, methyl JA (MeJA) levels and expression profiles of JA-related genes were analyzed in carrot roots and leaves at five developmental stages. MeJA levels in the roots and leaves were the highest at the first stage and decreased as carrot growth proceeded. Transcript levels of several JA-related genes (Dc13-LOX1, Dc13-LOX2, DcAOS, DcAOC, DcOPR2, DcOPR3, DcOPCL1, DcJAR1, DcJMT, DcCOI1, DcJAZ1, DcJAZ2, DcMYC2, DcCHIB/PR3, DcLEC, and DcVSP2) were not well correlated with MeJA accumulation during carrot root and leaf development. In addition, some JA-related genes (DcJAR1, DcJMT, DcCOI1, DcMYC2, and DcVSP2) showed differential expression between roots and leaves. These results suggest that JAs may regulate carrot plant growth in stage-dependent and organ-specific manners. Our work provides novel insights into JA accumulation and its potential roles during carrot growth and development.

  9. The Apoplastic Copper AMINE OXIDASE1 Mediates Jasmonic Acid-Induced Protoxylem Differentiation in Arabidopsis Roots1

    PubMed Central

    Ghuge, Sandip A.; Carucci, Andrea; Rodrigues-Pousada, Renato A.; Tisi, Alessandra; Franchi, Stefano; Tavladoraki, Paraskevi; Cona, Alessandra

    2015-01-01

    Polyamines are involved in key developmental processes and stress responses. Copper amine oxidases oxidize the polyamine putrescine (Put), producing an aldehyde, ammonia, and hydrogen peroxide (H2O2). The Arabidopsis (Arabidopsis thaliana) amine oxidase gene At4g14940 (AtAO1) encodes an apoplastic copper amine oxidase expressed at the early stages of vascular tissue differentiation in roots. Here, its role in root development and xylem differentiation was explored by pharmacological and forward/reverse genetic approaches. Analysis of the AtAO1 expression pattern in roots by a promoter::green fluorescent protein-β-glucuronidase fusion revealed strong gene expression in the protoxylem at the transition, elongation, and maturation zones. Methyl jasmonate (MeJA) induced AtAO1 gene expression in vascular tissues, especially at the transition and elongation zones. Early protoxylem differentiation was observed upon MeJA treatment along with Put level decrease and H2O2 accumulation in wild-type roots, whereas Atao1 loss-of-function mutants were unresponsive to the hormone. The H2O2 scavenger N,N1-dimethylthiourea reversed the MeJA-induced early protoxylem differentiation in wild-type seedlings. Likewise, Put, which had no effect on Atao1 mutants, induced early protoxylem differentiation in the wild type, this event being counteracted by N,N1-dimethylthiourea treatment. Consistently, AtAO1-overexpressing plants showed lower Put levels and early protoxylem differentiation concurrent with H2O2 accumulation in the root zone where the first protoxylem cells with fully developed secondary wall thickenings are found. These results show that the H2O2 produced via AtAO1-driven Put oxidation plays a role in MeJA signaling leading to early protoxylem differentiation in root. PMID:25883242

  10. Pithy Protection: Nicotiana attenuata’s Jasmonic Acid-Mediated Defenses Are Required to Resist Stem-Boring Weevil Larvae1[W][OA

    PubMed Central

    Diezel, Celia; Kessler, Danny; Baldwin, Ian T.

    2011-01-01

    Folivory is the best studied plant-herbivore interaction, but it is unclear whether the signaling and resistance traits important for the defense of leaves are also important for other plant parts. Larvae of the tobacco stem weevil, Trichobaris mucorea, burrow into stems of Nicotiana attenuata and feed on the pith. Transgenic N. attenuata lines silenced in signaling and foliar defense traits were evaluated in a 2-year field study for resistance against attack by naturally occurring T. mucorea larva. Plants silenced in early jasmonic acid (JA) biosynthesis (antisense [as]-lipoxygenase3 [lox3]; inverted repeat [ir]-allene oxide cyclase), JA perception (as-coronatine insensitive1), proteinase inhibitors (ir-pi), and nicotine (ir-putrescine methyl-transferase) direct defenses and lignin (ir-cad) biosynthesis were infested more frequently than wild-type plants. Plants unable to emit C6 aldehydes (as-hpl) had lower infestation rates, while plants silenced in late steps in JA biosynthesis (ir-acyl-coenzyme A oxidase, ir-opr) and silenced in diterpene glycoside production (ir-geranylgeranyl pyrophosphate synthase) did not differ from wild type. Pith choice assays revealed that ir-putrescine methyl-transferase, ir-coronatine insensitive1, and ir-lox3 pith, which all had diminished nicotine levels, were preferred by larvae compared to wild-type pith. The lack of preference for ir-lox2 and ir-cad piths, suggest that oviposition attraction and vascular defense, rather than pith palatability accounts for the higher attack rates observed for these plants. We conclude that traits that influence a plant’s apparency, stem hardness, and pith direct defenses all contribute to resistance against this herbivore whose attack can be devastating to N. attenuata’s fitness. PMID:21300916

  11. Modulatory role of jasmonic acid on photosynthetic pigments, antioxidants and stress markers of Glycine max L. under nickel stress.

    PubMed

    Sirhindi, Geetika; Mir, Mudaser Ahmad; Sharma, Poonam; Gill, Sarvajeet Singh; Kaur, Harpreet; Mushtaq, Ruquia

    2015-10-01

    Jasmonic acid (JA) is a very young candidate of plant growth regulators which is being explored for various antistress properties. Present study deals with the hypothesis that JA can modulate antioxidant mechanism of higher plants with tight regulation of biomembrane peroxidation, making plants tolerant to toxic Ni(2+). 2 mM NiCl2 as a source of Ni(2+) appeared as sub lethal dose for the growth of 15 days old Glycine max seedlings. Exogenous application of 1 μM and 1 nM JA prior to NiCl2 exposure, made seedlings of Glycine max more tolerant to Ni(2+)stress as compared to control untreated seedlings. Regulatory inhibition of MDA and H2O2 production by JA with or without Ni(2+) treatment made plants more resistant to Ni(2+) stress which may be associated with ameliorative activity of antioxidant enzymes system composed of SOD, POD, CAT and APOX. Ascorbate, a secondary metabolite synthesized from D-glucose act as an antioxidant in plant cells. Many fold enhancements in AsA content of Ni(2+) treated seedlings supplemented with different concentrations of JA was observed. Significant improvement in AsA levels by JA with or without Ni(2+) stress may involve two aspects, either denovo synthesis level regulation of AsA or recycling of AsA from an oxidized form. Improvement in total protein content showed the uplift modulation of transcriptional machinery by JA which was also maintained under Ni(2+) stress. Photosynthetic pigments as total chl, chl a and b showed inhibition in presence of Ni(2+) stress which was not found much effective under JA supplementation as compared to control. Present findings revealed that although JA was not helpful for protection of photosynthetic pigments but it modulates the other machinery of plants significantly including various antioxidants positively, while tightly inhibiting stress related processes responsible for lipid peroxidation to make plants tolerant to Ni(2+) stress.

  12. Metabolic Fate of Jasmonates in Tobacco Bright Yellow-2 Cells1

    PubMed Central

    Świątek, Agnieszka; Dongen, Walter Van; Esmans, Eddy L.; Onckelen, Harry Van

    2004-01-01

    Jasmonic acid and methyl jasmonate play an essential role in plant defense responses and pollen development. Their levels are temporarily and spatially controlled in plant tissue. However, whereas jasmonate biosynthesis is well studied, metabolic pathways downstream of jasmonic acid are less understood. We studied the uptake and metabolism of jasmonic acid and methyl jasmonate in tobacco (Nicotiana tabacum) Bright Yellow-2 suspension culture. We found that upon uptake, jasmonic acid was metabolized to its Glc and gentiobiose esters, and hydroxylation at C-11 or C-12 occurred. Free hydroxylated jasmonates were the preferential fraction of the culture medium. Upon hydrolysis of methyl jasmonate to jasmonic acid, a similar set of conversions occurs. In contrast to jasmonic acid, none of its derivatives interfere with the G2/M transition in synchronized tobacco Bright Yellow-2 cells. PMID:15133155

  13. Jasmonates during senescence: signals or products of metabolism?

    PubMed

    Seltmann, Martin A; Hussels, Wiebke; Berger, Susanne

    2010-11-01

    Jasmonic acid and derivatives are oxylipin signaling compounds derived from linolenic acid. Jasmonates accumulate during natural and dark-induced senescence but the increase in these compounds is not essential for the initiation or progression of these senescence processes. Here we report that during natural and dark-induced senescence the increase in jasmonate levels does not trigger jasmonate signaling. Furthermore we provide evidence that jasmonate production might result from membrane turnover during dark-induced senescence.

  14. Expression of a Flax Allene Oxide Synthase cDNA Leads to Increased Endogenous Jasmonic Acid (JA) Levels in Transgenic Potato Plants but Not to a Corresponding Activation of JA-Responding Genes.

    PubMed Central

    Harms, K.; Atzorn, R.; Brash, A.; Kuhn, H.; Wasternack, C.; Willmitzer, L.; Pena-Cortes, H.

    1995-01-01

    Both jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA), are thought to be significant components of the signaling pathway regulating the expression of plant defense genes in response to various stresses. JA and MeJA are plant lipid derivatives synthesized from [alpha]-linolenic acid by a lipoxygenase-mediated oxygenation leading to 13-hydroperoxylinolenic acid, which is subsequently transformed by the action of allene oxide synthase (AOS) and additional modification steps. AOS converts lipoxygenase-derived fatty acid hydroperoxide to allene epoxide, which is the precursor for JA formation. Overexpression of flax AOS cDNA under the regulation of the cauliflower mosaic virus 35S promoter in transgenic potato plants led to an increase in the endogenous level of JA. Transgenic plants had six- to 12-fold higher levels of JA than the nontransformed plants. Increased levels of JA have been observed when potato and tomato plants are mechanically wounded. Under these conditions, the proteinase inhibitor II (pin2) genes are expressed in the leaves. Despite the fact that the transgenic plants had levels of JA similar to those found in nontransgenic wounded plants, pin2 genes were not constitutively expressed in the leaves of these plants. Transgenic plants with increased levels of JA did not show changes in water state or in the expression of water stress-responsive genes. Furthermore, the transgenic plants overexpressing the flax AOS gene, and containing elevated levels of JA, responded to wounding or water stress by a further increase in JA and by activating the expression of either wound- or water stress-inducible genes. Protein gel blot analysis demonstrated that the flax-derived AOS protein accumulated in the chloroplasts of the transgenic plants. PMID:12242357

  15. Oligogalacturonide-mediated induction of a gene involved in jasmonic acid synthesis in response to the cell-wall-degrading enzymes of the plant pathogen Erwinia carotovora.

    PubMed

    Norman, C; Vidal, S; Palva, E T

    1999-07-01

    Identification of Arabidopsis thaliana genes responsive to plant cell-wall-degrading enzymes of Erwinia carotovora subsp. carotovora led to the isolation of a cDNA clone with high sequence homology to the gene for allene oxide synthase, an enzyme involved in the biosynthesis of jasmonates. Expression of the corresponding gene was induced by the extracellular enzymes from this pathogen as well as by treatment with methyl jasmonate and short oligogalacturonides (OGAs). This suggests that OGAs are involved in the induction of the jasmonate pathway during plant defense response to E. carotovora subsp. carotovora attack.

  16. GmCYP82A3, a Soybean Cytochrome P450 Family Gene Involved in the Jasmonic Acid and Ethylene Signaling Pathway, Enhances Plant Resistance to Biotic and Abiotic Stresses

    PubMed Central

    Yan, Qiang; Cui, Xiaoxia; Lin, Shuai; Gan, Shuping; Xing, Han; Dou, Daolong

    2016-01-01

    The cytochrome P450 monooxygenases (P450s) represent a large and important enzyme superfamily in plants. They catalyze numerous monooxygenation/hydroxylation reactions in biochemical pathways, P450s are involved in a variety of metabolic pathways and participate in the homeostasis of phytohormones. The CYP82 family genes specifically reside in dicots and are usually induced by distinct environmental stresses. However, their functions are largely unknown, especially in soybean (Glycine max L.). Here, we report the function of GmCYP82A3, a gene from soybean CYP82 family. Its expression was induced by Phytophthora sojae infection, salinity and drought stresses, and treatment with methyl jasmonate (MeJA) or ethephon (ETH). Its expression levels were consistently high in resistant cultivars. Transgenic Nicotiana benthamiana plants overexpressing GmCYP82A3 exhibited strong resistance to Botrytis cinerea and Phytophthora parasitica, and enhanced tolerance to salinity and drought stresses. Furthermore, transgenic plants were less sensitive to jasmonic acid (JA), and the enhanced resistance was accompanied with increased expression of the JA/ET signaling pathway-related genes. PMID:27588421

  17. A mitogen-activated protein kinase NtMPK4 activated by SIPKK is required for jasmonic acid signaling and involved in ozone tolerance via stomatal movement in tobacco.

    PubMed

    Gomi, Kenji; Ogawa, Daisuke; Katou, Shinpei; Kamada, Hiroshi; Nakajima, Nobuyoshi; Saji, Hikaru; Soyano, Takashi; Sasabe, Michiko; Machida, Yasunori; Mitsuhara, Ichiro; Ohashi, Yuko; Seo, Shigemi

    2005-12-01

    The mitogen-activated protein kinase (MAPK) cascade is involved in responses to biotic and abiotic stress in plants. In this study, we isolated a new MAPK, NtMPK4, which is a tobacco homolog of Arabidopsis MPK4 (AtMPK4). NtMPK4 was activated by wounding along with two other wound-responsive tobacco MAPKs, WIPK and SIPK. We found that NtMPK4 was activated by salicylic acid-induced protein kinase kinase (SIPKK), which has been isolated as an SIPK-interacting MAPK kinase. In NtMPK4 activity-suppressed tobacco, wound-induced expression of jasmonic acid (JA)-responsive genes was inhibited. NtMPK4-silenced plants showed enhanced sensitivity to ozone. Inversely, transgenic tobacco plants, in which SIPKK or the constitutively active type SIPKK(EE) was overexpressed, exhibited greater responsiveness to wounding with enhanced resistance to ozone. We further found that NtMPK4 was expressed preferentially in epidermis, and the enhanced sensitivity to ozone in NtMPK4-silenced plants was caused by an abnormal regulation of stomatal closure in an ABA-independent manner. These results suggest that NtMPK4 is involved in JA signaling and in stomatal movement.

  18. The antagonistic strain Bacillus subtilis UMAF6639 also confers protection to melon plants against cucurbit powdery mildew by activation of jasmonate- and salicylic acid-dependent defence responses.

    PubMed

    García-Gutiérrez, Laura; Zeriouh, Houda; Romero, Diego; Cubero, Jaime; de Vicente, Antonio; Pérez-García, Alejandro

    2013-05-01

    Biological control of plant diseases has gained acceptance in recent years. Bacillus subtilis UMAF6639 is an antagonistic strain specifically selected for the efficient control of the cucurbit powdery mildew fungus Podosphaera fusca, which is a major threat to cucurbits worldwide. The antagonistic activity relies on the production of the antifungal compounds iturin and fengycin. In a previous study, we found that UMAF6639 was able to induce systemic resistance (ISR) in melon and provide additional protection against powdery mildew. In the present work, we further investigated in detail this second mechanism of biocontrol by UMAF6639. First, we examined the signalling pathways elicited by UMAF6639 in melon plants, as well as the defence mechanisms activated in response to P. fusca. Second, we analysed the role of the lipopeptides produced by UMAF6639 as potential determinants for ISR activation. Our results demonstrated that UMAF6639 confers protection against cucurbit powdery mildew by activation of jasmonate- and salicylic acid-dependent defence responses, which include the production of reactive oxygen species and cell wall reinforcement. We also showed that surfactin lipopeptide is a major determinant for stimulation of the immune response. These results reinforce the biotechnological potential of UMAF6639 as a biological control agent.

  19. Interference with jasmonic acid-regulated gene expression is a general property of viral suppressors of RNA silencing but only partly explains virus-induced changes in plant–aphid interactions

    PubMed Central

    Westwood, Jack H.; Lewsey, Mathew G.; Murphy, Alex M.; Tungadi, Trisna; Bates, Anne; Gilligan, Christopher A.

    2014-01-01

    The cucumber mosaic virus (CMV) 2b viral suppressor of RNA silencing (VSR) inhibits host responses to jasmonic acid (JA), a chemical signal regulating resistance to insects. Previous experiments with a CMV subgroup IA strain and its 2b gene deletion mutant suggested that VSRs might neutralize aphid (Myzus persicae) resistance by inhibiting JA-regulated gene expression. To further investigate this, we examined JA-regulated gene expression and aphid performance in Nicotiana benthamiana infected with Potato virus X, Potato virus Y, Tobacco mosaic virus and a subgroup II CMV strain, as well as in transgenic plants expressing corresponding VSRs (p25, HC-Pro, 126 kDa and 2b). All the viruses or their VSRs inhibited JA-induced gene expression. However, this did not always correlate with enhanced aphid performance. Thus, VSRs are not the sole viral determinants of virus-induced changes in host–aphid interactions and interference with JA-regulated gene expression cannot completely explain enhanced aphid performance on virus-infected plants. PMID:24362960

  20. Global expression pattern comparison between low phosphorus insensitive 4 and WT Arabidopsis reveals an important role of reactive oxygen species and jasmonic acid in the root tip response to phosphate starvation.

    PubMed

    Chacón-López, Alejandra; Ibarra-Laclette, Enrique; Sánchez-Calderón, Lenin; Gutiérrez-Alanis, Dolores; Herrera-Estrella, Luis

    2011-03-01

    Plants are exposed to several biotic and abiotic stresses. A common environmental stress that plants have to face both in natural and agricultural ecosystems that impacts both its growth and development is low phosphate (Pi) availability. There has been an important progress in the knowledge of the molecular mechanisms by which plants cope with Pi deficiency. However, the mechanisms that mediate alterations in the architecture of the Arabidopsis root system responses to Pi starvation are still largely unknown. One of the most conspicuous developmental effects of low Pi on the Arabidopsis root system is the inhibition of primary root growth that is accompanied by loss of root meristematic activity. To identify signalling pathways potentially involved in the Arabidpsis root meristem response to Pi-deprivation, here we report the global gene expression analysis of the root tip of wild type and low phosphorus insensitive4 (lpi4) mutant grown under Pi limiting conditions. Differential gene expression analysis and physiological experiments show that changes in the redox status, probably mediated by jasmonic acid and ethylene, play an important role in the primary root meristem exhaustion process triggered by Pi-starvation.

  1. Low Red/Far-Red Ratios Reduce Arabidopsis Resistance to Botrytis cinerea and Jasmonate Responses via a COI1-JAZ10-Dependent, Salicylic Acid-Independent Mechanism1[C][W][OA

    PubMed Central

    Cerrudo, Ignacio; Keller, Mercedes M.; Cargnel, Miriam D.; Demkura, Patricia V.; de Wit, Mieke; Patitucci, Micaela S.; Pierik, Ronald; Pieterse, Corné M.J.; Ballaré, Carlos L.

    2012-01-01

    Light is an important modulator of plant immune responses. Here, we show that inactivation of the photoreceptor phytochrome B (phyB) by a low red/far-red ratio (R:FR), which is a signal of competition in plant canopies, down-regulates the expression of defense markers induced by the necrotrophic fungus Botrytis cinerea, including the genes that encode the transcription factor ETHYLENE RESPONSE FACTOR1 (ERF1) and the plant defensin PLANT DEFENSIN1.2 (PDF1.2). This effect of low R:FR correlated with a reduced sensitivity to jasmonate (JA), thus resembling the antagonistic effects of salicylic acid (SA) on JA responses. Low R:FR failed to depress PDF1.2 mRNA levels in a transgenic line in which PDF1.2 transcription was up-regulated by constitutive expression of ERF1 in a coronatine insensitive1 (coi1) mutant background (35S::ERF1/coi1). These results suggest that the low R:FR effect, in contrast to the SA effect, requires a functional SCFCOI1-JASMONATE ZIM-DOMAIN (JAZ) JA receptor module. Furthermore, the effect of low R:FR depressing the JA response was conserved in mutants impaired in SA signaling (sid2-1 and npr1-1). Plant exposure to low R:FR ratios and the phyB mutation markedly increased plant susceptibility to B. cinerea; the effect of low R:FR was (1) independent of the activation of the shade-avoidance syndrome, (2) conserved in the sid2-1 and npr1-1 mutants, and (3) absent in two RNA interference lines disrupted for the expression of the JAZ10 gene. Collectively, our results suggest that low R:FR ratios depress Arabidopsis (Arabidopsis thaliana) immune responses against necrotrophic microorganisms via a SA-independent mechanism that requires the JAZ10 transcriptional repressor and that this effect may increase plant susceptibility to fungal infection in dense canopies. PMID:22371506

  2. BIOSYNTHESIS AND ACTION OF JASMONATES IN PLANTS.

    PubMed

    Creelman, Robert A.; Mullet, John E.

    1997-06-01

    Jasmonic acid and its derivatives can modulate aspects of fruit ripening, production of viable pollen, root growth, tendril coiling, and plant resistance to insects and pathogens. Jasmonate activates genes involved in pathogen and insect resistance, and genes encoding vegetative storage proteins, but represses genes encoding proteins involved in photosynthesis. Jasmonic acid is derived from linolenic acid, and most of the enzymes in the biosynthetic pathway have been extensively characterized. Modulation of lipoxygenase and allene oxide synthase gene expression in transgenic plants raises new questions about the compartmentation of the biosynthetic pathway and its regulation. The activation of jasmonic acid biosynthesis by cell wall elicitors, the peptide systemin, and other compounds will be related to the function of jasmonates in plants. Jasmonate modulates gene expression at the level of translation, RNA processing, and transcription. Promoter elements that mediate responses to jasmonate have been isolated. This review covers recent advances in our understanding of how jasmonate biosynthesis is regulated and relates this information to knowledge of jasmonate modulated gene expression.

  3. Aspartic acid

    MedlinePlus

    ... also called asparaginic acid. Aspartic acid helps every cell in the body work. It plays a role in: Hormone production and release Normal nervous system function Plant sources of aspartic acid include: Legumes such as ...

  4. Folic Acid

    MedlinePlus

    Folic acid is a B vitamin. It helps the body make healthy new cells. Everyone needs folic acid. For women who may get pregnant, it is really important. Getting enough folic acid before and during pregnancy can prevent major birth ...

  5. Folic Acid

    MedlinePlus

    Folic acid is used to treat or prevent folic acid deficiency. It is a B-complex vitamin needed by ... Folic acid comes in tablets. It usually is taken once a day. Follow the directions on your prescription label ...

  6. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.

    1995-01-01

    Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

  7. Acid Rain.

    ERIC Educational Resources Information Center

    Openshaw, Peter

    1987-01-01

    Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

  8. Jasmonates: An Update on Biosynthesis, Signal Transduction and Action in Plant Stress Response, Growth and Development

    PubMed Central

    Wasternack, C.

    2007-01-01

    Background Jasmonates are ubiquitously occurring lipid-derived compounds with signal functions in plant responses to abiotic and biotic stresses, as well as in plant growth and development. Jasmonic acid and its various metabolites are members of the oxylipin family. Many of them alter gene expression positively or negatively in a regulatory network with synergistic and antagonistic effects in relation to other plant hormones such as salicylate, auxin, ethylene and abscisic acid. Scope This review summarizes biosynthesis and signal transduction of jasmonates with emphasis on new findings in relation to enzymes, their crystal structure, new compounds detected in the oxylipin and jasmonate families, and newly found functions. Conclusions Crystal structure of enzymes in jasmonate biosynthesis, increasing number of jasmonate metabolites and newly identified components of the jasmonate signal-transduction pathway, including specifically acting transcription factors, have led to new insights into jasmonate action, but its receptor(s) is/are still missing, in contrast to all other plant hormones. PMID:17513307

  9. Obeticholic Acid

    MedlinePlus

    Obeticholic acid is used alone or in combination with ursodiol (Actigall, Urso) to treat primary biliary cholangitis (PBC; a ... were not treated successfully with ursodiol alone. Obeticholic acid is in a class of medications called farnesoid ...

  10. Aminocaproic Acid

    MedlinePlus

    Aminocaproic acid is used to control bleeding that occurs when blood clots are broken down too quickly. This type ... the baby is ready to be born). Aminocaproic acid is also used to control bleeding in the ...

  11. Acid mucopolysaccharides

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003368.htm Acid mucopolysaccharides To use the sharing features on this page, please enable JavaScript. Acid mucopolysaccharides is a test that measures the amount ...

  12. Aristolochic Acids

    MedlinePlus

    ... Sciences NIH-HHS www.niehs.nih.gov Aristolochic Acids Key Points Report on Carcinogens Status Known to be human carcinogens Aristolochia Clematitis Aristolochic Acids n Known human carcinogens n Found in certain ...

  13. Ascorbic Acid

    MedlinePlus

    Ascorbic acid is used to prevent and treat scurvy, a disease caused by a lack of vitamin C in ... Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, syrup, chewable tablets, and liquid drops to ...

  14. Ethacrynic Acid

    MedlinePlus

    Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

  15. Amino acids

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/002222.htm Amino acids To use the sharing features on this page, please enable JavaScript. Amino acids are organic compounds that combine to form proteins . ...

  16. Valproic Acid

    MedlinePlus

    Valproic acid is used alone or with other medications to treat certain types of seizures. Valproic acid is also used to treat mania (episodes of ... to relieve headaches that have already begun. Valproic acid is in a class of medications called anticonvulsants. ...

  17. Fatty acids - trans fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The data supporting a negative effect of dietary trans fatty acids on cardiovascular disease risk is consistent. The primary dietary sources of trans fatty acids include partially hydrogenated fat and rudiment fat. The adverse effect of trans fatty acids on plasma lipoprotein profiles is consisten...

  18. Acid rain

    SciTech Connect

    Elsworth, S.

    1985-01-01

    This book was written in a concise and readable style for the lay public. It's purpose was to make the public aware of the damage caused by acid rain and to mobilize public opinion to favor the elimination of the causes of acid rain.

  19. Asparagusic acid.

    PubMed

    Mitchell, Stephen C; Waring, Rosemary H

    2014-01-01

    Asparagusic acid (1,2-dithiolane-4-carboxylic acid) is a simple sulphur-containing 5-membered heterocyclic compound that appears unique to asparagus, though other dithiolane derivatives have been identified in non-food species. This molecule, apparently innocuous toxicologically to man, is the most probable culprit responsible for the curious excretion of odorous urine following asparagus ingestion. The presence of the two adjacent sulphur atoms leads to an enhanced chemical reactivity, endowing it with biological properties including the ability to substitute potentially for α-lipoic acid in α-keto-acid oxidation systems. This brief review collects the scattered data available in the literature concerning asparagusic acid and highlights its properties, intermediary metabolism and exploratory applications.

  20. Acid rain

    SciTech Connect

    Sweet, W.

    1980-06-20

    Acid precipitation includes not only rain but also acidified snow, hail and frost, as well as sulfur and nitrogen dust. The principal source of acid precipitation is pollution emitted by power plants and smelters. Sulfur and nitrogen compounds contained in the emissions combine with moisture to form droplets with a high acid content - sometimes as acidic as vinegar. When sufficiently concentrated, these acids can kill fish and damage material structures. Under certain circumstances they may reduce crop and forest yields and cause or aggravate respiratory diseases in humans. During the summer, especially, pollutants tend to collect over the Great Lakes in high pressure systems. Since winds typically are westerly and rotate clockwise around high pressure systems, the pollutants gradually are dispersed throughout the eastern part of the continent.

  1. Acid fog

    SciTech Connect

    Hileman, B.

    1983-03-01

    Fog in areas of southern California previously thought to be pollution-free has been shown to have a pH as low as 1.69. It has been found to be most acidic after smoggy days, suggesting that it forms on the aerosol associated with the previously exiting smog. Studies on Whiteface Mountain in the Adirondacks show that fog water is often 10 times as acidic as rainwater. As a result of their studies, California plans to spend $4 million on acid deposition research in the coming year. (JMT)

  2. Mefenamic Acid

    MedlinePlus

    ... as mefenamic acid may cause ulcers, bleeding, or holes in the stomach or intestine. These problems may ... like coffee grounds, blood in the stool, or black and tarry stools.Keep all appointments with your ...

  3. Acid Rain

    MedlinePlus

    ... EPA Is Doing Acid Rain Program Cross-State Air Pollution Rule Progress Reports Educational Resources Kid's Site for ... Monitoring National Atmospheric Deposition Program (NADP) Exit Interstate Air Pollution Transport Contact Us to ask a question, provide ...

  4. Folic Acid

    MedlinePlus

    ... folic acid can hide signs that you lack vitamin B12, which can cause nerve damage. 10 Do I ... Rosenberg, I.H., et al. (2007). Folate and vitamin B12 status in relation to anemia, macrocytosis and cognitive ...

  5. Acid Precipitation

    ERIC Educational Resources Information Center

    Likens, Gene E.

    1976-01-01

    Discusses the fact that the acidity of rain and snow falling on parts of the U.S. and Europe has been rising. The reasons are still not entirely clear and the consequences have yet to be well evaluated. (MLH)

  6. Acidic precipitation

    SciTech Connect

    Martin, H.C.

    1987-01-01

    At the International Symposium on Acidic Precipitation, over 400 papers were presented, and nearly 200 of them are included here. They provide an overview of the present state of the art of acid rain research. The Conference focused on atmospheric science (monitoring, source-receptor relationships), aquatic effects (marine eutrophication, lake acidification, impacts on plant and fish populations), and terrestrial effects (forest decline, soil acidification, etc.).

  7. The PP2C-type phosphatase AP2C1, which negatively regulates MPK4 and MPK6, modulates innate immunity, jasmonic acid, and ethylene levels in Arabidopsis.

    PubMed

    Schweighofer, Alois; Kazanaviciute, Vaiva; Scheikl, Elisabeth; Teige, Markus; Doczi, Robert; Hirt, Heribert; Schwanninger, Manfred; Kant, Merijn; Schuurink, Robert; Mauch, Felix; Buchala, Antony; Cardinale, Francesca; Meskiene, Irute

    2007-07-01

    Wound signaling pathways in plants are mediated by mitogen-activated protein kinases (MAPKs) and stress hormones, such as ethylene and jasmonates. In Arabidopsis thaliana, the transmission of wound signals by MAPKs has been the subject of detailed investigations; however, the involvement of specific phosphatases in wound signaling is not known. Here, we show that AP2C1, an Arabidopsis Ser/Thr phosphatase of type 2C, is a novel stress signal regulator that inactivates the stress-responsive MAPKs MPK4 and MPK6. Mutant ap2c1 plants produce significantly higher amounts of jasmonate upon wounding and are more resistant to phytophagous mites (Tetranychus urticae). Plants with increased AP2C1 levels display lower wound activation of MAPKs, reduced ethylene production, and compromised innate immunity against the necrotrophic pathogen Botrytis cinerea. Our results demonstrate a key role for the AP2C1 phosphatase in regulating stress hormone levels, defense responses, and MAPK activities in Arabidopsis and provide evidence that the activity of AP2C1 might control the plant's response to B. cinerea.

  8. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.

    1993-01-01

    Acid deposition, or acid rain as it is more commonly referred to, has become a widely publicized environmental issue in the U.S. over the past decade. The term usually conjures up images of fish kills, dying forests, "dead" lakes, and damage to monuments and other historic artifacts. The primary cause of acid deposition is emission of S02 and NOx to the atmosphere during the combustion of fossil fuels. Oxidation of these compounds in the atmosphere forms strong acids - H2SO4 and HNO3 - which are returned to the Earth in rain, snow, fog, cloud water, and as dry deposition.Although acid deposition has only recently been recognized as an environmental problem in the U.S., it is not a new phenomenon (Cogbill & Likens 1974). As early as the middle of the 17th century in England, the deleterious effects of industrial emissions on plants, animals, and humans, and the atmospheric transport of pollutants between England and France had become issues of concern (Evelyn 1661, Graunt 1662). It is interesting that well over three hundred years ago in England, recommendations were made to move industry outside of towns and build higher chimneys to spread the pollution into "distant parts." Increasing the height of smokestacks has helped alleviate local problems, but has exacerbated others. In the U.S. the height of the tallest smokestack has more than doubled, and the average height of smokestacks has tripled since the 1950s (Patrick et al 1981). This trend occurred in most industrialized nations during the 20th century and has had the effect of transforming acid rain from a local urban problem into a problem of global scale.

  9. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.; Dietrich, W.E.; Sposito, Garrison

    1997-01-01

    Acid deposition, or acid rain as it is more commonly referred to, has become a widely publicized environmental issue in the U.S. over the past decade. The term usually conjures up images of fish kills, dying forests, "dead" lakes, and damage to monuments and other historic artifacts. The primary cause of acid deposition is emission of S02 and NOx to the atmosphere during the combustion of fossil fuels. Oxidation of these compounds in the atmosphere forms strong acids - H2SO4 and HNO3 - which are returned to the Earth in rain, snow, fog, cloud water, and as dry deposition.Although acid deposition has only recently been recognized as an environmental problem in the U.S., it is not a new phenomenon (Cogbill & Likens 1974). As early as the middle of the 17th century in England, the deleterious effects of industrial emissions on plants, animals, and humans, and the atmospheric transport of pollutants between England and France had become issues of concern (Evelyn 1661, Graunt 1662). It is interesting that well over three hundred years ago in England, recommendations were made to move industry outside of towns and build higher chimneys to spread the pollution into "distant parts." Increasing the height of smokestacks has helped alleviate local problems, but has exacerbated others. In the U.S. the height of the tallest smokestack has more than doubled, and the average height of smokestacks has tripled since the 1950s (Patrick et al 1981). This trend occurred in most industrialized nations during the 20th century and has had the effect of transforming acid rain from a local urban problem into a problem of global scale.

  10. Soybean Aphid Infestation Induces Changes in Fatty Acid Metabolism in Soybean

    PubMed Central

    Kanobe, Charles; McCarville, Michael T.; O’Neal, Matthew E.; Tylka, Gregory L.; MacIntosh, Gustavo C.

    2015-01-01

    The soybean aphid (Aphis glycines Matsumura) is one of the most important insect pests of soybeans in the North-central region of the US. It has been hypothesized that aphids avoid effective defenses by inhibition of jasmonate-regulated plant responses. Given the role fatty acids play in jasmonate-induced plant defenses, we analyzed the fatty acid profile of soybean leaves and seeds from aphid-infested plants. Aphid infestation reduced levels of polyunsaturated fatty acids in leaves with a concomitant increase in palmitic acid. In seeds, a reduction in polyunsaturated fatty acids was associated with an increase in stearic acid and oleic acid. Soybean plants challenged with the brown stem rot fungus or with soybean cyst nematodes did not present changes in fatty acid levels in leaves or seeds, indicating that the changes induced by aphids are not a general response to pests. One of the polyunsaturated fatty acids, linolenic acid, is the precursor of jasmonate; thus, these changes in fatty acid metabolism may be examples of “metabolic hijacking” by the aphid to avoid the induction of effective defenses. Based on the changes in fatty acid levels observed in seeds and leaves, we hypothesize that aphids potentially induce interference in the fatty acid desaturation pathway, likely reducing FAD2 and FAD6 activity that leads to a reduction in polyunsaturated fatty acids. Our data support the idea that aphids block jasmonate-dependent defenses by reduction of the hormone precursor. PMID:26684003

  11. Salicylic acids

    PubMed Central

    Hayat, Shamsul; Irfan, Mohd; Wani, Arif; Nasser, Alyemeni; Ahmad, Aqil

    2012-01-01

    Salicylic acid is well known phytohormone, emerging recently as a new paradigm of an array of manifestations of growth regulators. The area unleashed yet encompassed the applied agriculture sector to find the roles to strengthen the crops against plethora of abiotic and biotic stresses. The skipped part of integrated picture, however, was the evolutionary insight of salicylic acid to either allow or discard the microbial invasion depending upon various internal factors of two interactants under the prevailing external conditions. The metabolic status that allows the host invasion either as pathogenesis or symbiosis with possible intermediary stages in close systems has been tried to underpin here. PMID:22301975

  12. Selenious acid

    Integrated Risk Information System (IRIS)

    Selenious acid ; CASRN 7783 - 00 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  13. Dichloroacetic acid

    Integrated Risk Information System (IRIS)

    EPA 635 / R - 03 / 007 www.epa.gov / iris TOXICOLOGICAL REVIEW OF DICHLOROACETIC ACID ( CAS No . 79 - 43 - 6 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) August 2003 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document has been revi

  14. Trichloroacetic acid

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 09 / 003F www.epa.gov / iris TOXICOLOGICAL REVIEW OF TRICHLOROACETIC ACID ( CAS No . 76 - 03 - 9 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) September 2011 U.S . Environmental Protection Agency Washington , DC ii DISCLAIMER This document has

  15. Acid rain

    SciTech Connect

    Not Available

    1984-06-01

    An overview is presented of acid rain and the problems it causes to the environment worldwide. The acidification of lakes and streams is having a dramatic effect on aquatic life. Aluminum, present in virtually all forest soils, leaches out readily under acid conditions and interferes with the gills of all fish, some more seriously than others. There is evidence of major damage to forests in European countries. In the US, the most severe forest damage appears to be in New England, New York's Adirondacks, and the central Appalachians. This small region is part of a larger area of the Northeast and Canada that appears to have more acid rainfall than the rest of the country. It is downwind from major coal burning states, which produce about one quarter of US SO/sub 2/ emissions and one sixth of nitrogen oxide emissions. Uncertainties exist over the causes of forest damage and more research is needed before advocating expensive programs to reduce rain acidity. The President's current budget seeks an expansion of research funds from the current $30 million per year to $120 million.

  16. Benzoic acid

    Integrated Risk Information System (IRIS)

    Benzoic acid ; CASRN 65 - 85 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  17. Formic acid

    Integrated Risk Information System (IRIS)

    Formic acid ; CASRN 64 - 18 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect

  18. Acrylic acid

    Integrated Risk Information System (IRIS)

    Acrylic acid ( CASRN 79 - 10 - 7 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  19. Phosphoric acid

    Integrated Risk Information System (IRIS)

    Phosphoric acid ; CASRN 7664 - 38 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  20. Cacodylic acid

    Integrated Risk Information System (IRIS)

    Cacodylic acid ; CASRN 75 - 60 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  1. Azelaic acid.

    PubMed

    Nazzaro-Porro, M

    1987-12-01

    This review is an update on the literature accumulated over the past 10 years following the original observation that azelaic acid, a naturally occurring and nontoxic C9 dicarboxylic acid, possesses significant biologic properties and a potential as a therapeutic agent. These studies have shown that azelaic acid is a reversible inhibitor of tyrosinase and other oxidoreductases in vitro and that it inhibits mitochondrial respiration. It can also inhibit anaerobic glycolysis. Both in vitro and in vivo it has an antimicrobial effect on both aerobic and anaerobic (Propionibacterium acnes) microorganisms. In tissue culture it exerts a dose- and time-dependent cytotoxic effect on malignant melanocytes, associated with mitochondrial damage and inhibition of deoxyribonucleic acid (DNA) synthesis. Tumoral cell lines not containing tyrosinase are equally affected. Normal cells in culture exposed to the same concentrations of the diacid that are toxic for tumoral cells are in general not damaged. Radioactive azelaic acid has been shown to penetrate tumoral cells at a higher level than normal cells of the corresponding line. Topically applied (a 20% cream), it has been shown to be of therapeutic value in skin disorders of different etiologies. Its beneficial effect on various forms of acne (comedogenic, papulopustular, nodulocystic) has been clearly demonstrated. Particularly important is its action on abnormal melanocytes, which has led to the possibility of obtaining good results on melasma and highly durable therapeutic responses on lentigo maligna. It is also capable of causing regression of cutaneous malignant melanoma, but its role in melanoma therapy remains to be investigated.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Loss of Plastoglobule Kinases ABC1K1 and ABC1K3 Causes Conditional Degreening, Modified Prenyl-Lipids, and Recruitment of the Jasmonic Acid Pathway[W

    PubMed Central

    Lundquist, Peter K.; Poliakov, Anton; Giacomelli, Lisa; Friso, Giulia; Appel, Mason; McQuinn, Ryan P.; Krasnoff, Stuart B.; Rowland, Elden; Ponnala, Lalit; Sun, Qi; van Wijk, Klaas J.

    2013-01-01

    Plastoglobules (PGs) are plastid lipid-protein particles. This study examines the function of PG-localized kinases ABC1K1 and ABC1K3 in Arabidopsis thaliana. Several lines of evidence suggested that ABC1K1 and ABC1K3 form a protein complex. Null mutants for both genes (abc1k1 and abc1k3) and the double mutant (k1 k3) displayed rapid chlorosis upon high light stress. Also, k1 k3 showed a slower, but irreversible, senescence-like phenotype during moderate light stress that was phenocopied by drought and nitrogen limitation, but not cold stress. This senescence-like phenotype involved degradation of the photosystem II core and upregulation of chlorophyll degradation. The senescence-like phenotype was independent of the EXECUTER pathway that mediates genetically controlled cell death from the chloroplast and correlated with increased levels of the singlet oxygen–derived carotenoid β-cyclocitral, a retrograde plastid signal. Total PG volume increased during light stress in wild type and k1 k3 plants, but with different size distributions. Isolated PGs from k1 k3 showed a modified prenyl-lipid composition, suggesting reduced activity of PG-localized tocopherol cyclase (VTE1), and was consistent with loss of carotenoid cleavage dioxygenase 4. Plastid jasmonate biosynthesis enzymes were recruited to the k1 k3 PGs but not wild-type PGs, while pheophytinase, which is involved in chlorophyll degradation, was induced in k1 k3 and not wild-type plants and was localized to PGs. Thus, the ABC1K1/3 complex contributes to PG function in prenyl-lipid metabolism, stress response, and thylakoid remodeling. PMID:23673981

  3. Comparative proteomic analysis of differentially expressed proteins in β-aminobutyric acid enhanced Arabidopsis thaliana tolerance to simulated acid rain.

    PubMed

    Liu, Tingwu; Jiang, Xinwu; Shi, Wuliang; Chen, Juan; Pei, Zhenming; Zheng, Hailei

    2011-05-01

    Acid rain is a worldwide environmental issue that has seriously destroyed forest ecosystems. As a highly effective and broad-spectrum plant resistance-inducing agent, β-aminobutyric acid could elevate the tolerance of Arabidopsis when subjected to simulated acid rain. Using comparative proteomic strategies, we analyzed 203 significantly varied proteins of which 175 proteins were identified responding to β-aminobutyric acid in the absence and presence of simulated acid rain. They could be divided into ten groups according to their biological functions. Among them, the majority was cell rescue, development and defense-related proteins, followed by transcription, protein synthesis, folding, modification and destination-associated proteins. Our conclusion is β-aminobutyric acid can lead to a large-scale primary metabolism change and simultaneously activate antioxidant system and salicylic acid, jasmonic acid, abscisic acid signaling pathways. In addition, β-aminobutyric acid can reinforce physical barriers to defend simulated acid rain stress.

  4. Hydroxycarboxylic acids and salts

    DOEpatents

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

    2015-02-24

    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  5. Loss of function of fatty acid desturase7 in tomato enhances basal aphid resistance in a salicylate-dependent manner

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Jasmonic acid (JA) and its derivatives mediate induced resistance against caterpillars and other herbivores that cause tissue disruption. Far less is known about the role of jasmonates in plant interactions with phloem-feeding insects such as aphids. This study compared responses in tomato (Solanu...

  6. Jasmonates: biosynthesis, perception, signal transduction and action in plant stress response, growth and development. An update to the 2007 review in Annals of Botany

    PubMed Central

    Wasternack, C.; Hause, B.

    2013-01-01

    Background Jasmonates are important regulators in plant responses to biotic and abiotic stresses as well as in development. Synthesized from lipid-constituents, the initially formed jasmonic acid is converted to different metabolites including the conjugate with isoleucine. Important new components of jasmonate signalling including its receptor were identified, providing deeper insight into the role of jasmonate signalling pathways in stress responses and development. Scope The present review is an update of the review on jasmonates published in this journal in 2007. New data of the last five years are described with emphasis on metabolites of jasmonates, on jasmonate perception and signalling, on cross-talk to other plant hormones and on jasmonate signalling in response to herbivores and pathogens, in symbiotic interactions, in flower development, in root growth and in light perception. Conclusions The last few years have seen breakthroughs in the identification of JASMONATE ZIM DOMAIN (JAZ) proteins and their interactors such as transcription factors and co-repressors, and the crystallization of the jasmonate receptor as well as of the enzyme conjugating jasmonate to amino acids. Now, the complex nature of networks of jasmonate signalling in stress responses and development including hormone cross-talk can be addressed. PMID:23558912

  7. Acidic domains around nucleic acids.

    PubMed Central

    Lamm, G; Pack, G R

    1990-01-01

    The hydrogen ion concentration in the vicinity of DNA was mapped out within the Poisson-Boltzmann approximation. Experimental conditions were modeled by assuming Na-DNA to be solvated in a buffer solution containing 45 mM Tris and 3 mM Mg cations at pH 7.5. Three regions of high H+ concentration (greater than 10 microM) are predicted: one throughout the minor groove of DNA and two localized in the major groove near N7 of guanine and C5 of cytosine for a G.C base pair. These acidic domains correlate well with the observed covalent binding sites of benzo[a]pyrene epoxide (N2 of guanine) and of aflatoxin B1 epoxide (N7 of guanine), chemical carcinogens that presumably undergo acid catalysis to form highly reactive carbocations that ultimately bind to DNA. It is suggested that these regions of high H+ concentration may also be of concern in understanding interactions involving proteins and noncarcinogenic molecules with or near nucleic acids. PMID:2123348

  8. The Ubiquitin System and Jasmonate Signaling

    PubMed Central

    Nagels Durand, Astrid; Pauwels, Laurens; Goossens, Alain

    2016-01-01

    The ubiquitin (Ub) system is involved in most, if not all, biological processes in eukaryotes. The major specificity determinants of this system are the E3 ligases, which bind and ubiquitinate specific sets of proteins and are thereby responsible for target recruitment to the proteasome or other cellular processing machineries. The Ub system contributes to the regulation of the production, perception and signal transduction of plant hormones. Jasmonic acid (JA) and its derivatives, known as jasmonates (JAs), act as signaling compounds regulating plant development and plant responses to various biotic and abiotic stress conditions. We provide here an overview of the current understanding of the Ub system involved in JA signaling. PMID:27135226

  9. Folic Acid and Pregnancy

    MedlinePlus

    ... Feeding Your 1- to 2-Year-Old Folic Acid and Pregnancy KidsHealth > For Parents > Folic Acid and ... before conception and during early pregnancy . About Folic Acid Folic acid, sometimes called folate, is a B ...

  10. Understanding Acid Rain

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

    The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

  11. New Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to new compounds, 7,10-dihydroxy-8(E)-octadecen...

  12. New bioactive fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octad...

  13. Acid rain

    SciTech Connect

    Boyle, R.H.; Boyle, R.A.

    1983-01-01

    Acid rain, says Boyle is a chemical leprosy eating into the face of North America and Europe, perhaps the major ecological problem of our time. Boyle describes the causes and scope of the phenomenon; the effects on man, wildlife, water, and our cultural heritage. He probes the delays of politicians and the frequent self-serving arguments advanced by industry in the face of what scientists have proved. The solutions he offers are to strengthen the Clean Air Act and require emission reductions that can be accomplished by establishing emission standards on a regional or bubble basis, burn low-sulfur coal, install scrubbers at critical plants, and invest in alternative energy sources. 73 references, 1 figure.

  14. Jasmonate is essential for insect defense in Arabidopsis.

    PubMed

    McConn, M; Creelman, R A; Bell, E; Mullet, J E; Browse, J

    1997-05-13

    The signaling pathways that allow plants to mount defenses against chewing insects are known to be complex. To investigate the role of jasmonate in wound signaling in Arabidopsis and to test whether parallel or redundant pathways exist for insect defense, we have studied a mutant (fad3-2 fad7-2 fad8) that is deficient in the jasmonate precursor linolenic acid. Mutant plants contained negligible levels of jasmonate and showed extremely high mortality ( approximately 80%) from attack by larvae of a common saprophagous fungal gnat, Bradysia impatiens (Diptera: Sciaridae), even though neighboring wild-type plants were largely unaffected. Application of exogenous methyl jasmonate substantially protected the mutant plants and reduced mortality to approximately 12%. These experiments precisely define the role of jasmonate as being essential for the induction of biologically effective defense in this plant-insect interaction. The transcripts of three wound-responsive genes were shown not to be induced by wounding of mutant plants but the same transcripts could be induced by application of methyl jasmonate. By contrast, measurements of transcript levels for a gene encoding glutathione S-transferase demonstrated that wound induction of this gene is independent of jasmonate synthesis. These results indicate that the mutant will be a good genetic model for testing the practical effectiveness of candidate defense genes.

  15. Jasmonate signaling in plant development and defense response to multiple (a)biotic stresses.

    PubMed

    Santino, Angelo; Taurino, Marco; De Domenico, Stefania; Bonsegna, Stefania; Poltronieri, Palmiro; Pastor, Victoria; Flors, Victor

    2013-07-01

    Plants frequently live in environments characterized by the presence of simultaneous and different stresses. The intricate and finely tuned molecular mechanisms activated by plants in response to abiotic and biotic environmental factors are not well understood, and less is known about the integrative signals and convergence points activated by plants in response to multiple (a)biotic stresses. Phytohormones play a key role in plant development and response to (a)biotic stresses. Among these, one of the most important signaling molecules is an oxylipin, the plant hormone jasmonic acid. Oxylipins are derived from oxygenation of polyunsaturated fatty acids. Jasmonic acid and its volatile derivative methyl jasmonate have been considered for a long time to be the bioactive forms due to their physiological effects and abundance in the plant. However, more recent studies showed unambiguously that they are only precursors of the active forms represented by some amino acid conjugates. Upon developmental or environmental stimuli, jasmonates are synthesized and accumulate transiently. Upon perception, jasmonate signal transduction process is finely tuned by a complex mechanism comprising specific repressor proteins which in turn control a number of transcription factors regulating the expression of jasmonate responsive genes. We discuss the latest discoveries about the role of jasmonates in plants resistance mechanism against biotic and abiotic stresses. Finally, the deep interplay of different phytohormones in stresses signaling will be also discussed.

  16. Maize death acids, 9-lipoxygenase derived cyclopente(a)nones, display activity as cytotoxic phytoalexins and transcriptional mediators

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant damage promotes the interaction of lipoxygenases (LOX) with fatty acids yielding 9-hydroperoxides, 13-hydroperoxides and complex arrays of oxylipins. The action of 13-LOX on linolenic acid enables production of 12-oxo-phytodienoic acid (12-OPDA) and its downstream products, termed jasmonates. ...

  17. [Teichoic acids from lactic acid bacteria].

    PubMed

    Livins'ka, O P; Harmasheva, I L; Kovalenko, N K

    2012-01-01

    The current view of the structural diversity of teichoic acids and their involvement in the biological activity of lactobacilli has been reviewed. The mechanisms of effects of probiotic lactic acid bacteria, in particular adhesive and immunostimulating functions have been described. The prospects of the use of structure data of teichoic acid in the assessment of intraspecific diversity of lactic acid bacteria have been also reflected.

  18. Organic acids tunably catalyze carbonic acid decomposition.

    PubMed

    Kumar, Manoj; Busch, Daryle H; Subramaniam, Bala; Thompson, Ward H

    2014-07-10

    Density functional theory calculations predict that the gas-phase decomposition of carbonic acid, a high-energy, 1,3-hydrogen atom transfer reaction, can be catalyzed by a monocarboxylic acid or a dicarboxylic acid, including carbonic acid itself. Carboxylic acids are found to be more effective catalysts than water. Among the carboxylic acids, the monocarboxylic acids outperform the dicarboxylic ones wherein the presence of an intramolecular hydrogen bond hampers the hydrogen transfer. Further, the calculations reveal a direct correlation between the catalytic activity of a monocarboxylic acid and its pKa, in contrast to prior assumptions about carboxylic-acid-catalyzed hydrogen-transfer reactions. The catalytic efficacy of a dicarboxylic acid, on the other hand, is significantly affected by the strength of an intramolecular hydrogen bond. Transition-state theory estimates indicate that effective rate constants for the acid-catalyzed decomposition are four orders-of-magnitude larger than those for the water-catalyzed reaction. These results offer new insights into the determinants of general acid catalysis with potentially broad implications.

  19. Plasma amino acids

    MedlinePlus

    Amino acids blood test ... types of methods used to determine the individual amino acid levels in the blood. ... test is done to measure the level of amino acids in the blood. An increased level of a ...

  20. Uric acid - urine

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003616.htm Uric acid urine test To use the sharing features on this page, please enable JavaScript. The uric acid urine test measures the level of uric acid ...

  1. Facts about Folic Acid

    MedlinePlus

    ... Information For... Media Policy Makers Facts About Folic Acid Language: English Español (Spanish) Recommend on Facebook Tweet ... of the baby's brain and spine. About folic acid Folic acid is a B vitamin. Our bodies ...

  2. Stomach acid test

    MedlinePlus

    Gastric acid secretion test ... of the cells in the stomach to release acid. The stomach contents are then removed and analyzed. ... 3.5). These numbers are converted to actual acid production in units of milliequivalents per hour in ...

  3. Methylmalonic acid blood test

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003565.htm Methylmalonic acid blood test To use the sharing features on this page, please enable JavaScript. The methylmalonic acid blood test measures the amount of methylmalonic acid ...

  4. Uric acid test (image)

    MedlinePlus

    Uric acid urine test is performed to check for the amount of uric acid in urine. Urine is collected over a 24 ... testing. The most common reason for measuring uric acid levels is in the diagnosis or treatment of ...

  5. Fatty Acid Oxidation Disorders

    MedlinePlus

    ... other health conditions > Fatty acid oxidation disorders Fatty acid oxidation disorders E-mail to a friend Please ... these disorders, go to genetests.org . What fatty acid oxidation disorders are tested for in newborn screening? ...

  6. Functional Analysis of Jasmonates in Rice through Mutant Approaches

    PubMed Central

    Dhakarey, Rohit; Kodackattumannil Peethambaran, Preshobha; Riemann, Michael

    2016-01-01

    Jasmonic acid, one of the major plant hormones, is, unlike other hormones, a lipid-derived compound that is synthesized from the fatty acid linolenic acid. It has been studied intensively in many plant species including Arabidopsis thaliana, in which most of the enzymes participating in its biosynthesis were characterized. In the past 15 years, mutants and transgenic plants affected in the jasmonate pathway became available in rice and facilitate studies on the functions of this hormone in an important crop. Those functions are partially conserved compared to other plant species, and include roles in fertility, response to mechanical wounding and defense against herbivores. However, new and surprising functions have also been uncovered by mutant approaches, such as a close link between light perception and the jasmonate pathway. This was not only useful to show a phenomenon that is unique to rice but also helped to establish this role in plant species where such links are less obvious. This review aims to provide an overview of currently available rice mutants and transgenic plants in the jasmonate pathway and highlights some selected roles of jasmonate in this species, such as photomorphogenesis, and abiotic and biotic stress. PMID:27135235

  7. Analysis of low molecular weight acids by negative mode matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    PubMed

    Shroff, Rohit; Muck, Alexander; Svatos, Ales

    2007-01-01

    Free 9-aminoacridine base is demonstrated to be a suitable matrix for negative mode matrix-assisted laser desorption/ionization time-of-flight mass spectrometric (MALDI-TOFMS) analysis of a wide range of low molecular weight organic acids including aliphatic (from acetic to palmitic acid), aromatic acids, phytohormones (e.g. jasmonic and salicylic acids), and amino acids. Low limits of quantitation in the femtomolar range (jasmonic - 250 fmol; caffeic - 160 fmol and salicylic - 12.5 fmol) and linear detector response over two concentration orders in the pico- and femtomolar range are extremely encouraging for the direct study of such acids in complex biological matrices.

  8. Acid distribution in phosphoric acid fuel cells

    SciTech Connect

    Okae, I.; Seya, A.; Umemoto, M.

    1996-12-31

    Electrolyte acid distribution among each component of a cell is determined by capillary force when the cell is not in operation, but the distribution under the current load conditions had not been clear so far. Since the loss of electrolyte acid during operation is inevitable, it is necessary to store enough amount of acid in every cell. But it must be under the level of which the acid disturbs the diffusion of reactive gases. Accordingly to know the actual acid distribution during operation in a cell is very important. In this report, we carried out experiments to clarify the distribution using small single cells.

  9. Acid tolerance in amphibians

    SciTech Connect

    Pierce, B.A.

    1985-04-01

    Studies of amphibian acid tolerance provide information about the potential effects of acid deposition on amphibian communities. Amphibians as a group appear to be relatively acid tolerant, with many species suffering increased mortality only below pH 4. However, amphibians exhibit much intraspecific variation in acid tolerance, and some species are sensitive to even low levels of acidity. Furthermore, nonlethal effects, including depression of growth rates and increases in developmental abnormalities, can occur at higher pH.

  10. Jasmonates induce nonapoptotic death in high-resistance mutant p53-expressing B-lymphoma cells

    PubMed Central

    Fingrut, Orit; Reischer, Dorit; Rotem, Ronit; Goldin, Natalia; Altboum, Irit; Zan-Bar, Israel; Flescher, Eliezer

    2005-01-01

    Mutations in p53, a tumor suppressor gene, occur in more than half of human cancers. Therefore, we tested the hypothesis that jasmonates (novel anticancer agents) can induce death in mutated p53-expressing cells. Two clones of B-lymphoma cells were studied, one expressing wild-type (wt) p53 and the other expressing mutated p53. Jasmonic acid and methyl jasmonate (0.25–3 mM) were each equally cytotoxic to both clones, whereas mutant p53-expressing cells were resistant to treatment with the radiomimetic agent neocarzinostatin and the chemotherapeutic agent bleomycin. Neocarzinostatin and bleomycin induced an elevation in the p53 levels in wt p53-expressing cells, whereas methyl jasmonate did not. Methyl jasmonate induced mostly apoptotic death in the wt p53-expressing cells, while no signs of early apoptosis were detected in mutant p53-expressing cells. In contrast, neocarzinostatin and bleomycin induced death only in wt p53-expressing cells, in an apoptotic mode. Methyl jasmonate induced a rapid depletion of ATP in both clones. In both clones, oligomycin (a mitochondrial ATP synthase inhibitor) did not increase ATP depletion induced by methyl jasmonate, whereas inhibition of glycolysis with 2-deoxyglucose did. High glucose levels protected both clones from methyl jasmonate-induced ATP depletion (and reduced methyl jasmonate-induced cytotoxicity), whereas high levels of pyruvate did not. These results suggest that methyl jasmonate induces ATP depletion mostly by compromising oxidative phosphorylation in the mitochondria. In conclusion, jasmonates can circumvent the resistance of mutant p53-expressing cells towards chemotherapy by inducing a nonapoptotic cell death. PMID:16170329

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

    NASA Astrophysics Data System (ADS)

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

    2007-09-01

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

  12. Toxicity of adipic acid.

    PubMed

    Kennedy, Gerald L

    2002-05-01

    Adipic acid has very low acute toxicity in rats with an LD50 > 5000 mg/kg. Adipic acid produced mild to no skin irritation on intact guinea pig skin as a 50% concentration in propylene glycol; it was not a skin sensitizer. Adipic acid caused mild conjunctival irritation in washed rabbit eyes; in unwashed rabbit eyes, there was mild conjunctival irritation, minimal iritis, but no corneal effects. Adipic acid dust may irritate the mucous membranes of the lungs and nose. In a 2-year feeding study, rats fed adipic acid at concentrations up to 5% in the diet exhibited only weight loss. Adipic acid is not genetically active in a wide variety of assay systems. Adipic acid caused no developmental toxicity in mice, rats, rabbits, or hamsters when administered orally. Adipic acid is partially metabolized in humans; the balance is eliminated unchanged in the urine. Adipic acid is slightly to moderately toxic to fish, daphnia, and algae in acute tests.

  13. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    This communication notes the actual magnitude of the acidity in acidic fog particles and suggests a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air.

  14. Acid Thunder: Acid Rain and Ancient Mesoamerica

    ERIC Educational Resources Information Center

    Kahl, Jonathan D. W.; Berg, Craig A.

    2006-01-01

    Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few…

  15. Polymorphism in jasmonate signaling partially accounts for the variety of volatiles produced by Nicotiana attenuata plants in a native population.

    PubMed

    Schuman, Meredith C; Heinzel, Nicolas; Gaquerel, Emmanuel; Svatos, Ales; Baldwin, Ian T

    2009-01-01

    Herbivore- and jasmonate-induced volatile organic compounds (VOCs), which mediate indirect defense, must provide reliable information for predators that frequently learn to associate their release with feeding herbivores. Yet little is known about variation of these cues within populations of native plants, on a scale encountered by predators. We examined variation in herbivore-elicited VOC emissions and patterns of herbivore-induced jasmonate signaling from accessions of Nicotiana attenuata co-occurring in a native population. VOC emissions elicited by herbivore oral secretions (OS) and by methyl jasmonate (MJ) were characterized using gas chromatography-mass spectrometry (GC-MS), high-resolution two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-ToF-MS) and micro-hydrolysis and micro-hydrogenation reactions. Accessions varied in emissions of abundant (trans-alpha-bergamotene, alpha-duprezianene, trans-beta-ocimene, and cis-3-hexenol) and total detectable VOCs, as well as the accumulation of jasmonates, the jasmonate antagonist salicylic acid (SA), abscisic acid (ABA) and jasmonate signaling-related transcripts after OS elicitation. Yet MJ treatment exacerbated differences in VOC emission, suggesting that much variation in VOC emission is caused by processes downstream of jasmonate signaling. Co-occurring N. attenuata plants emit different VOCs following simulated herbivore elicitation as a result in part of differences in jasmonate production and responsiveness, which could reduce the effectiveness of induced indirect defense.

  16. Fatty acid analogs

    DOEpatents

    Elmaleh, David R.; Livni, Eli

    1985-01-01

    In one aspect, a radioactively labeled analog of a fatty acid which is capable of being taken up by mammalian tissue and which exhibits an in vivo beta-oxidation rate below that with a corresponding radioactively labeled fatty acid.

  17. Omega-3 fatty acids

    PubMed Central

    Schwalfenberg, Gerry

    2006-01-01

    OBJECTIVE To examine evidence for the role of omega-3 fatty acids in cardiovascular disease. QUALITY OF EVIDENCE PubMed was searched for articles on the role of omega-3 fatty acids in cardiovascular disease. Level I and II evidence indicates that omega-3 fatty acids are beneficial in improving cardiovascular outcomes. MAIN MESSAGE Dietary intake of omega-3 fatty acids has declined by 80% during the last 100 years, while intake of omega-6 fatty acids has greatly increased. Omega-3 fatty acids are cardioprotective mainly due to beneficial effects on arrhythmias, atherosclerosis, inflammation, and thrombosis. There is also evidence that they improve endothelial function, lower blood pressure, and significantly lower triglycerides. CONCLUSION There is good evidence in the literature that increasing intake of omega-3 fatty acids improves cardiac outcomes. Physicians need to integrate dietary recommendations for consumption of omega-3 fatty acids into their usual cardiovascular care. PMID:16812965

  18. Sulfuric acid poisoning

    MedlinePlus

    Sulfuric acid is a very strong chemical that is corrosive. Corrosive means it can cause severe burns and ... or mucous membranes. This article discusses poisoning from sulfuric acid. This article is for information only. Do NOT ...

  19. Lactic acid test

    MedlinePlus

    Lactate test ... test. Exercise can cause a temporary increase in lactic acid levels. ... not getting enough oxygen. Conditions that can increase lactic acid levels include: Heart failure Liver disease Lung disease ...

  20. Folic Acid Quiz

    MedlinePlus

    ... About Us Information For... Media Policy Makers Folic Acid Quiz Language: English Español (Spanish) Recommend on Facebook ... button beside the question. Good Luck! 1. Folic acid is: A a B vitamin B a form ...

  1. Hydrochloric acid poisoning

    MedlinePlus

    Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

  2. Azelaic Acid Topical

    MedlinePlus

    Azelaic acid gel and foam is used to clear the bumps, lesions, and swelling caused by rosacea (a skin ... redness, flushing, and pimples on the face). Azelaic acid cream is used to treat the pimples and ...

  3. Zoledronic Acid Injection

    MedlinePlus

    Zoledronic acid (Reclast) is used to prevent or treat osteoporosis (condition in which the bones become thin and weak ... of life,' end of regular menstrual periods). Zoledronic acid (Reclast) is also used to treat osteoporosis in ...

  4. Alpha Hydroxy Acids

    MedlinePlus

    ... Cosmetics Home Cosmetics Products & Ingredients Ingredients Alpha Hydroxy Acids Share Tweet Linkedin Pin it More sharing options ... for Industry: Labeling for Cosmetics Containing Alpha Hydroxy Acids The following information is intended to answer questions ...

  5. Uric Acid Test

    MedlinePlus

    ... products and services. Advertising & Sponsorship: Policy | Opportunities Uric Acid Share this page: Was this page helpful? Also known as: Serum Urate; UA Formal name: Uric Acid Related tests: Synovial Fluid Analysis , Kidney Stone Analysis , ...

  6. Amino Acid Metabolism Disorders

    MedlinePlus

    ... breaks the food parts down into sugars and acids, your body's fuel. Your body can use this ... process. One group of these disorders is amino acid metabolism disorders. They include phenylketonuria (PKU) and maple ...

  7. Valproic Acid and Pregnancy

    MedlinePlus

    ... live chat Live Help Fact Sheets Share Valproic Acid and Pregnancy Wednesday, 01 July 2015 In every ... This sheet talks about whether exposure to valproic acid may increase the risk for birth defects over ...

  8. Aminocaproic Acid Injection

    MedlinePlus

    Aminocaproic acid injection is used to control bleeding that occurs when blood clots are broken down too quickly. This ... the baby is ready to be born). Aminocaproic acid injection is also used to control bleeding in ...

  9. Omega-6 Fatty Acids

    MedlinePlus

    Omega-6 fatty acids are types of fats. Some types are found in vegetable oils, including corn, evening primrose seed, safflower, and soybean oils. Other types of omega-6 fatty acids are found in black currant seed, borage seed, ...

  10. Deoxycholic Acid Injection

    MedlinePlus

    Deoxycholic acid injection is used to improve the appearance and profile of moderate to severe submental fat ('double chin'; fatty tissue located under the chin). Deoxycholic acid injection is in a class of medications called ...

  11. PRODUCTION OF TRIFLUOROACETIC ACID

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-07-19

    A method is given for the production of improved yields of trifluoroacetic acid. The compound is prepared by oxidizing m-aminobenzotrifluoride with an alkali metal or alkaline earth metal permanganate at a temperature in the range of 80 deg C to 100 deg C while dissolved ln a mixture of water with glacial acetic acid and/or trifluoroacetic acid. Preferably a mixture of water and trifluoroacetic acid ls used as the solvent.

  12. Refining Lurgi tar acids

    SciTech Connect

    Greco, N.P.

    1984-04-17

    There is disclosed a process for removing tar bases and neutral oils from the Lurgi tar acids by treating the tar acids with aqueous sodium bisulfate to change the tar bases to salts and to hydrolyze the neutral oils to hydrolysis products and distilling the tar acids to obtain refined tar acid as the distillate while the tar base salts and neutral oil hydrolysis products remain as residue.

  13. Plant fatty acid hydroxylases

    DOEpatents

    Somerville, Chris; Broun, Pierre; van de Loo, Frank

    2001-01-01

    This invention relates to plant fatty acyl hydroxylases. Methods to use conserved amino acid or nucleotide sequences to obtain plant fatty acyl hydroxylases are described. Also described is the use of cDNA clones encoding a plant hydroxylase to produce a family of hydroxylated fatty acids in transgenic plants. In addition, the use of genes encoding fatty acid hydroxylases or desaturases to alter the level of lipid fatty acid unsaturation in transgenic plants is described.

  14. 78 FR 20029 - Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... AGENCY 40 CFR Part 180 Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic..., polymer with adipic acid, linoleic acid, oleic acid and ricinoleic acid (CAS Reg. No. 1357486-09- 9) when used as an inert ingredient in a pesticide formulation. Advance Polymer Technology submitted a...

  15. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    The chemical composition of fog particles has become of considerable interest, because of both the possibility of interpreting atmospheric- chemistry processes in fog particles in terms of the principles of aqueous chemistry and the potential health effects of species present in fog particles. The acidity of fog particles has received wide attention. This communication noted the actual magnitude of the excess acidity in acidic fog particles and suggested a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air. (DP)

  16. What Is Acid Rain?

    ERIC Educational Resources Information Center

    Likens, Gene E.

    2004-01-01

    Acid rain is the collective term for any type of acidified precipitation: rain, snow, sleet, and hail, as well as the presence of acidifying gases, particles, cloud water, and fog in the atmosphere. The increased acidity, primarily from sulfuric and nitric acids, is generated as a by-product of the combustion of fossil fuels such as coal and oil.…

  17. The Acid Rain Reader.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  18. Acid Rain Study Guide.

    ERIC Educational Resources Information Center

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  19. Acid Lipase Disease

    MedlinePlus

    ... Page You are here Home » Disorders » All Disorders Acid Lipase Disease Information Page Acid Lipase Disease Information Page What research is being ... research to understand lipid storage diseases such as acid lipase deficiency. Additional research studies hope to identify ...

  20. [alpha]-Oxocarboxylic Acids

    ERIC Educational Resources Information Center

    Kerber, Robert C.; Fernando, Marian S.

    2010-01-01

    Several [alpha]-oxocarboxylic acids play key roles in metabolism in plants and animals. However, there are inconsistencies between the structures as commonly portrayed and the reported acid ionization constants, which result because the acids are predominantly hydrated in aqueous solution; that is, the predominant form is RC(OH)[subscript 2]COOH…

  1. Jasmonate signaling is activated in the very early stages of iron deficiency responses in rice roots.

    PubMed

    Kobayashi, Takanori; Itai, Reiko Nakanishi; Senoura, Takeshi; Oikawa, Takaya; Ishimaru, Yasuhiro; Ueda, Minoru; Nakanishi, Hiromi; Nishizawa, Naoko K

    2016-07-01

    Under low iron availability, plants induce the expression of various genes involved in iron uptake and translocation at the transcriptional level. This iron deficiency response is affected by various plant hormones, but the roles of jasmonates in this response are not well-known. We investigated the involvement of jasmonates in rice iron deficiency responses. High rates of jasmonate-inducible genes were induced during the very early stages of iron deficiency treatment in rice roots. Many jasmonate-inducible genes were also negatively regulated by the ubiquitin ligases OsHRZ1 and OsHRZ2 and positively regulated by the transcription factor IDEF1. Ten out of 35 genes involved in jasmonate biosynthesis and signaling were rapidly induced at 3 h of iron deficiency treatment, and this induction preceded that of known iron deficiency-inducible genes involved in iron uptake and translocation. Twelve genes involved in jasmonate biosynthesis and signaling were also upregulated in HRZ-knockdown roots. Endogenous concentrations of jasmonic acid and jasmonoyl isoleucine tended to be rapidly increased in roots in response to iron deficiency treatment, whereas these concentrations were higher in HRZ-knockdown roots under iron-sufficient conditions. Analysis of the jasmonate-deficient cpm2 mutant revealed that jasmonates repress the expression of many iron deficiency-inducible genes involved in iron uptake and translocation under iron sufficiency, but this repression is partly canceled under an early stage of iron deficiency. These results indicate that jasmonate signaling is activated during the very early stages of iron deficiency, which is partly regulated by IDEF1 and OsHRZs.

  2. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow; Mary Ann D.; Dahlberg, James E.

    2010-11-09

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  3. Amino acid analysis

    NASA Technical Reports Server (NTRS)

    Winitz, M.; Graff, J. (Inventor)

    1974-01-01

    The process and apparatus for qualitative and quantitative analysis of the amino acid content of a biological sample are presented. The sample is deposited on a cation exchange resin and then is washed with suitable solvents. The amino acids and various cations and organic material with a basic function remain on the resin. The resin is eluted with an acid eluant, and the eluate containing the amino acids is transferred to a reaction vessel where the eluant is removed. Final analysis of the purified acylated amino acid esters is accomplished by gas-liquid chromatographic techniques.

  4. Editorial: Acid precipitation

    SciTech Connect

    1995-09-01

    This editorial focuses on acid rain and the history of public and governmental response to acid rain. Comments on a book by Gwineth Howell `Acid Rain and Acid Waters` are included. The editor feels that Howells has provide a service to the environmental scientific community, with a textbook useful to a range of people, as well as a call for decision makers to learn from the acid rain issue and use it as a model for more sweeping global environmental issues. A balance is needed among several parameters such as level of evidence, probability that the evidence will lead to a specific direction and the cost to the global community. 1 tab.

  5. Nucleic acid detection compositions

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James L.

    2008-08-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  6. Nucleic acid detection assays

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James E.

    2005-04-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  7. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor L.; Brow, Mary Ann D.; Dahlberg, James E.

    2007-12-11

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  8. Nucleic acid detection kits

    DOEpatents

    Hall, Jeff G.; Lyamichev, Victor I.; Mast, Andrea L.; Brow, Mary Ann; Kwiatkowski, Robert W.; Vavra, Stephanie H.

    2005-03-29

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof. The present invention further relates to methods and devices for the separation of nucleic acid molecules based on charge. The present invention also provides methods for the detection of non-target cleavage products via the formation of a complete and activated protein binding region. The invention further provides sensitive and specific methods for the detection of nucleic acid from various viruses in a sample.

  9. [Biosynthesis of adipic acid].

    PubMed

    Han, Li; Chen, Wujiu; Yuan, Fei; Zhang, Yuanyuan; Wang, Qinhong; Ma, Yanhe

    2013-10-01

    Adipic acid is a six-carbon dicarboxylic acid, mainly for the production of polymers such as nylon, chemical fiber and engineering plastics. Its annual demand is close to 3 million tons worldwide. Currently, the industrial production of adipic acid is based on the oxidation of aromatics from non-renewable petroleum resources by chemo-catalytic processes. It is heavily polluted and unsustainable, and the possible alternative method for adipic acid production should be developed. In the past years, with the development of synthetic biology and metabolic engineering, green and clean biotechnological methods for adipic acid production attracted more attention. In this study, the research advances of adipic acid and its precursor production are reviewed, followed by addressing the perspective of the possible new pathways for adipic acid production.

  10. Acidic Ionic Liquids.

    PubMed

    Amarasekara, Ananda S

    2016-05-25

    Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

  11. Boric acid and boronic acids inhibition of pigeonpea urease.

    PubMed

    Reddy, K Ravi Charan; Kayastha, Arvind M

    2006-08-01

    Urease from the seeds of pigeonpea was competitively inhibited by boric acid, butylboronic acid, phenylboronic acid, and 4-bromophenylboronic acid; 4-bromophenylboronic acid being the strongest inhibitor, followed by boric acid > butylboronic acid > phenylboronic acid, respectively. Urease inhibition by boric acid is maximal at acidic pH (5.0) and minimal at alkaline pH (10.0), i.e., the trigonal planar B(OH)3 form is a more effective inhibitor than the tetrahedral B(OH)4 -anionic form. Similarly, the anionic form of phenylboronic acid was least inhibiting in nature.

  12. Biotransformation of cinnamic acid, p-coumaric acid, caffeic acid, and ferulic acid by plant cell cultures of Eucalyptus perriniana.

    PubMed

    Katsuragi, Hisashi; Shimoda, Kei; Kubota, Naoji; Nakajima, Nobuyoshi; Hamada, Hatsuyuki; Hamada, Hiroki

    2010-01-01

    Biotransformations of phenylpropanoids such as cinnamic acid, p-coumaric acid, caffeic acid, and ferulic acid were investigated with plant-cultured cells of Eucalyptus perriniana. The plant-cultured cells of E. perriniana converted cinnamic acid into cinnamic acid β-D-glucopyranosyl ester, p-coumaric acid, and 4-O-β-D-glucopyranosylcoumaric acid. p-Coumaric acid was converted into 4-O-β-D-glucopyranosylcoumaric acid, p-coumaric acid β-D-glucopyranosyl ester, 4-O-β-D-glucopyranosylcoumaric acid β-D-glucopyranosyl ester, a new compound, caffeic acid, and 3-O-β-D-glucopyranosylcaffeic acid. On the other hand, incubation of caffeic acid with cultured E. perriniana cells gave 3-O-β-D-glucopyranosylcaffeic acid, 3-O-(6-O-β-D-glucopyranosyl)-β-D-glucopyranosylcaffeic acid, a new compound, 3-O-β-D-glucopyranosylcaffeic acid β-D-glucopyranosyl ester, 4-O-β-D-glucopyranosylcaffeic acid, 4-O-β-D-glucopyranosylcaffeic acid β-D-glucopyranosyl ester, ferulic acid, and 4-O-β-D-glucopyranosylferulic acid. 4-O-β-D-Glucopyranosylferulic acid, ferulic acid β-D-glucopyranosyl ester, and 4-O-β-D-glucopyranosylferulic acid β-D-glucopyranosyl ester were isolated from E. perriniana cells treated with ferulic acid.

  13. Process for the preparation of lactic acid and glyceric acid

    DOEpatents

    Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

    2008-12-02

    Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

  14. Microorganisms for producing organic acids

    DOEpatents

    Pfleger, Brian Frederick; Begemann, Matthew Brett

    2014-09-30

    Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

  15. Jasmonates are essential factors inducing gummosis in tulips: mode of action of jasmonates focusing on sugar metabolism.

    PubMed

    Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi

    2005-05-01

    The purpose of this study was to know the mechanism of jasmonates to induce gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) shoots, especially on the focus of sugar metabolism. Gummosis in the first internode of tulip plants was induced by the application of methyl jasmonate (JA-Me, 1% w/w in lanolin) and jasmonic acid (JA, 1% w/w in lanolin) 5 days after application and strongly stimulated by the simultaneous application of ethylene-releasing compound, ethephon (2-chloroethylphosphonic acid, 1% w/w in lanolin), although ethephon alone had little effect. JA-Me stimulated ethylene production of the first internodes of tulips, ethylene production increasing up to more than 5 times at day 1 and day 3 after the application. On the other hand, application of ethephon did not increase endogenous levels of jasmonates in tulip stems. Analysis of composition of tulip gums revealed that they were consisted of glucuronoarabinoxylan with an average molecular weight of ca. 700 kDa. JA-Me strongly decreased the total amount of soluble sugars in tulip stems even in 1 day after application, being ca. 50% of initial values 5 days after application, but ethephon did not. However, both JA-Me and ethephon had almost no effect on the neutral sugar compositions of soluble sugars mainly consisting of glucose, mannose and xylose in ratio of 20:2:1 and traces of arabinose. Both JA-Me and ethephon applied exogenously stimulated senescence of tulip shoots shown by the loss of chlorophyll. These results strongly suggest that the essential factor of gummosis in tulips is jasmonates affecting the sugar metabolism in tulip shoots. The mode of action of jasmonates to induce gummosis of tulip shoots is discussed in relation to ethylene production, sugar metabolism and senescence.

  16. Overexpression of salicylic acid carboxyl methyltransferase reduces salicylic acid-mediated pathogen resistance in Arabidopsis thaliana.

    PubMed

    Koo, Yeon Jong; Kim, Myeong Ae; Kim, Eun Hye; Song, Jong Tae; Jung, Choonkyun; Moon, Joon-Kwan; Kim, Jeong-Han; Seo, Hak Soo; Song, Sang Ik; Kim, Ju-Kon; Lee, Jong Seob; Cheong, Jong-Joo; Choi, Yang Do

    2007-05-01

    We cloned a salicylic acid/benzoic acid carboxyl methyltransferase gene, OsBSMT1, from Oryza sativa. A recombinant OsBSMT1 protein obtained by expressing the gene in Escherichia coli exhibited carboxyl methyltransferase activity in reactions with salicylic acid (SA), benzoic acid (BA), and de-S-methyl benzo(1,2,3)thiadiazole-7-carbothioic acid (dSM-BTH), producing methyl salicylate (MeSA), methyl benzoate (MeBA), and methyl dSM-BTH (MeBTH), respectively. Compared to wild-type plants, transgenic Arabidopsis overexpressing OsBSMT1 accumulated considerably higher levels of MeSA and MeBA, some of which were vaporized into the environment. Upon infection with the bacterial pathogen Pseudomonas syringae or the fungal pathogen Golovinomyces orontii, transgenic plants failed to accumulate SA and its glucoside (SAG), becoming more susceptible to disease than wild-type plants. OsBSMT1-overexpressing Arabidopsis showed little induction of PR-1 when treated with SA or G. orontii. Notably, incubation with the transgenic plant was sufficient to trigger PR-1 induction in neighboring wild-type plants. Together, our results indicate that in the absence of SA, MeSA alone cannot induce a defense response, yet it serves as an airborne signal for plant-to-plant communication. We also found that jasmonic acid (JA) induced AtBSMT1, which may contribute to an antagonistic effect on SA signaling pathways by depleting the SA pool in plants.

  17. Citric Acid Alternative to Nitric Acid Passivation

    NASA Technical Reports Server (NTRS)

    Lewis, Pattie L. (Compiler)

    2013-01-01

    The Ground Systems Development and Operations GSDO) Program at NASA John F. Kennedy Space Center (KSC) has the primary objective of modernizing and transforming the launch and range complex at KSC to benefit current and future NASA programs along with other emerging users. Described as the launch support and infrastructure modernization program in the NASA Authorization Act of 2010, the GSDO Program will develop and implement shared infrastructure and process improvements to provide more flexible, affordable, and responsive capabilities to a multi-user community. In support of the GSDO Program, the purpose of this project is to demonstratevalidate citric acid as a passivation agent for stainless steel. Successful completion of this project will result in citric acid being qualified for use as an environmentally preferable alternative to nitric acid for passivation of stainless steel alloys in NASA and DoD applications.

  18. Recovery of organic acids

    DOEpatents

    Verser, Dan W.; Eggeman, Timothy J.

    2009-10-13

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  19. Recovery of organic acids

    DOEpatents

    Verser, Dan W [Menlo Park, CA; Eggeman, Timothy J [Lakewood, CO

    2011-11-01

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  20. USGS Tracks Acid Rain

    USGS Publications Warehouse

    Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.

    1995-01-01

    The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

  1. Parenteral Nutrition: Amino Acids.

    PubMed

    Hoffer, Leonard John

    2017-03-10

    There is growing interest in nutrition therapies that deliver a generous amount of protein, but not a toxic amount of energy, to protein-catabolic critically ill patients. Parenteral amino acids can achieve this goal. This article summarizes the biochemical and nutritional principles that guide parenteral amino acid therapy, explains how parenteral amino acid solutions are formulated, and compares the advantages and disadvantages of different parenteral amino acid products with enterally-delivered whole protein products in the context of protein-catabolic critical illness.

  2. Parenteral Nutrition: Amino Acids

    PubMed Central

    Hoffer, Leonard John

    2017-01-01

    There is growing interest in nutrition therapies that deliver a generous amount of protein, but not a toxic amount of energy, to protein-catabolic critically ill patients. Parenteral amino acids can achieve this goal. This article summarizes the biochemical and nutritional principles that guide parenteral amino acid therapy, explains how parenteral amino acid solutions are formulated, and compares the advantages and disadvantages of different parenteral amino acid products with enterally-delivered whole protein products in the context of protein-catabolic critical illness. PMID:28287411

  3. Diterpenoid acids from Grindelia nana.

    PubMed

    Mahmoud, A A; Ahmed, A A; Tanaka, T; Iinuma, M

    2000-03-01

    Two new norditerpenoid acids of the labdane-type (norgrindelic acids), 4,5-dehydro-6-oxo-18-norgrindelic acid (1) and 4beta-hydroxy-6-oxo-19-norgrindelic acid (2), as well as a new grindelic acid derivative, 18-hydroxy-6-oxogrindelic acid (3), were isolated from the aerial parts of Grindelia nana. In addition, the known compounds, 6-oxogrindelic acid, grindelic acid, methyl grindeloate, 7alpha,8alpha-epoxygrindelic acid, and 4alpha-carboxygrindelic acid were also isolated. The structures of the new compounds were characterized on the basis of spectroscopic analysis.

  4. Differential impact of lipoxygenase 2 and jasmonates on natural and stress-induced senescence in Arabidopsis.

    PubMed

    Seltmann, Martin A; Stingl, Nadja E; Lautenschlaeger, Jens K; Krischke, Markus; Mueller, Martin J; Berger, Susanne

    2010-04-01

    Jasmonic acid and related oxylipins are controversially discussed to be involved in regulating the initiation and progression of leaf senescence. To this end, we analyzed profiles of free and esterified oxylipins during natural senescence and upon induction of senescence-like phenotypes by dark treatment and flotation on sorbitol in Arabidopsis (Arabidopsis thaliana). Jasmonic acid and free 12-oxo-phytodienoic acid increased during all three processes, with the strongest increase of jasmonic acid after dark treatment. Arabidopside content only increased considerably in response to sorbitol treatment. Monogalactosyldiacylglycerols and digalactosyldiacylglycerols decreased during these treatments and aging. Lipoxygenase 2-RNA interference (RNAi) plants were generated, which constitutively produce jasmonic acid and 12-oxo-phytodienoic acid but do not exhibit accumulation during natural senescence or upon stress treatment. Chlorophyll loss during aging and upon dark incubation was not altered, suggesting that these oxylipins are not involved in these processes. In contrast, lipoxygenase 2-RNAi lines and the allene oxid synthase-deficient mutant dde2 were less sensitive to sorbitol than the wild type, indicating that oxylipins contribute to the response to sorbitol stress.

  5. Characterization of 12-Oxo-Phytodienoic Acid Reductase in Corn

    PubMed Central

    Vick, Brady A.; Zimmerman, Don C.

    1986-01-01

    12-Oxo-phytodienoic acid reductase, an enzyme of the biosynthetic pathway that converts linolenic acid to jasmonic acid, has been characterized from the kernel and seedlings of corn (Zea mays L.). The molecular weight of the enzyme, estimated by gel filtration, was 54,000. Optimum enzyme activity was observed over a broad pH range, from pH 6.8 to 9.0. The enzyme had a Km of 190 micromolar for its substrate, 12-oxo-phytodienoic acid. The preferred reductant was NADPH, for which the enzyme exhibited a Km of 13 micromolar, compared with 4.2 millimolar for NADH. Reductase activity was low in the corn kernel but increased five-fold by the fifth day after germination and then gradually declined. PMID:16664582

  6. Pathogen-induced systemic activation of a plant defensin gene in Arabidopsis follows a salicylic acid-independent pathway.

    PubMed Central

    Penninckx, I A; Eggermont, K; Terras, F R; Thomma, B P; De Samblanx, G W; Buchala, A; Métraux, J P; Manners, J M; Broekaert, W F

    1996-01-01

    A 5-kD plant defensin was purified from Arabidopsis leaves challenged with the fungus Alternaria brassicicola and shown to possess antifungal properties in vitro. The corresponding plant defensin gene was induced after treatment of leaves with methyl jasmonate or ethylene but not with salicylic acid or 2,6-dichloroisonicotinic acid. When challenged with A. brassicicola, the levels of the plant defensin protein and mRNA rose both in inoculated leaves and in nontreated leaves of inoculated plants (systemic leaves). These events coincided with an increase in the endogenous jasmonic acid content of both types of leaves. Systemic pathogen-induced expression of the plant defensin gene was unaffected in Arabidopsis transformants (nahG) or mutants (npr1 and cpr1) affected in the salicylic acid response but was strongly reduced in the Arabidopsis mutants eln2 and col1 that are blocked in their response to ethylene and methyl jasmonate, respectively. Our results indicate that systemic pathogen-induced expression of the plant defensin gene in Arabidopsis is independent of salicylic acid but requires components of the ethylene and jasmonic acid response. PMID:8989885

  7. VvMJE1 of the grapevine (Vitis vinifera) VvMES methylesterase family encodes for methyl jasmonate esterase and has a role in stress response

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The known members of the plant methyl esterase (MES) family catalyze hydrolysis of a C-O ester linkage of methyl esters of several phytohormones including indole-3-acetic acid, salicylic acid, and jasmonic acid. The genome of grapevine (Vitis vinifera) was found to contain 15 MES genes, designated V...

  8. Structure of Acid phosphatases.

    PubMed

    Araujo, César L; Vihko, Pirkko T

    2013-01-01

    Acid phosphatases are enzymes that have been studied extensively due to the fact that their dysregulation is associated with pathophysiological conditions. This characteristic has been exploited for the development of diagnostic and therapeutic methods. As an example, prostatic acid phosphatase was the first marker for metastatic prostate cancer diagnosis and the dysregulation of tartrate resistant acid phosphatase is associated with abnormal bone resorption linked to osteoporosis. The pioneering crystallization studies on prostatic acid phosphatase and mammalian tartrate-resistant acid phosphatase conformed significant milestones towards the elucidation of the mechanisms followed by these enzymes (Schneider et al., EMBO J 12:2609-2615, 1993). Acid phosphatases are also found in nonmammalian species such as bacteria, fungi, parasites, and plants, and most of them share structural similarities with mammalian acid phosphatase enzymes. Acid phosphatase (EC 3.1.3.2) enzymes catalyze the hydrolysis of phosphate monoesters following the general equation. Phosphate monoester + H2O -->/<-- alcohol + phosphate. The general classification "acid phosphatase" relies only on the optimum acidic pH for the enzymatic activity in assay conditions using non-physiological substrates. These enzymes accept a wide range of substrates in vitro, ranging from small organic molecules to phosphoproteins, constituting a heterogeneous group of enzymes from the structural point of view. These structural differences account for the divergence in cofactor dependences and behavior against substrates, inhibitors, and activators. In this group only the tartrate-resistant acid phosphatase is a metallo-enzyme whereas the other members do not require metal-ion binding for their catalytic activity. In addition, tartrate-resistant acid phosphatase and erythrocytic acid phosphatase are not inhibited by L-(+)-tartrate ion while the prostatic acid phosphatase is tartrate-sensitive. This is an important

  9. Folic Acid and Pregnancy

    MedlinePlus

    ... Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding Your 1- to 3-Month-Old Feeding Your 4- to 7-Month-Old Feeding Your 8- to 12-Month-Old Feeding Your 1- to 2-Year-Old Folic Acid ... > For Parents > Folic Acid and Pregnancy A A A What's ...

  10. Bile acid transporters

    PubMed Central

    Dawson, Paul A.; Lan, Tian; Rao, Anuradha

    2009-01-01

    In liver and intestine, transporters play a critical role in maintaining the enterohepatic circulation and bile acid homeostasis. Over the past two decades, there has been significant progress toward identifying the individual membrane transporters and unraveling their complex regulation. In the liver, bile acids are efficiently transported across the sinusoidal membrane by the Na+ taurocholate cotransporting polypeptide with assistance by members of the organic anion transporting polypeptide family. The bile acids are then secreted in an ATP-dependent fashion across the canalicular membrane by the bile salt export pump. Following their movement with bile into the lumen of the small intestine, bile acids are almost quantitatively reclaimed in the ileum by the apical sodium-dependent bile acid transporter. The bile acids are shuttled across the enterocyte to the basolateral membrane and effluxed into the portal circulation by the recently indentified heteromeric organic solute transporter, OSTα-OSTβ. In addition to the hepatocyte and enterocyte, subgroups of these bile acid transporters are expressed by the biliary, renal, and colonic epithelium where they contribute to maintaining bile acid homeostasis and play important cytoprotective roles. This article will review our current understanding of the physiological role and regulation of these important carriers. PMID:19498215

  11. Analysis of Organic Acids.

    ERIC Educational Resources Information Center

    Griswold, John R.; Rauner, Richard A.

    1990-01-01

    Presented are the procedures and a discussion of the results for an experiment in which students select unknown carboxylic acids, determine their melting points, and investigate their solubility behavior in water and ethanol. A table of selected carboxylic acids is included. (CW)

  12. Salicylic Acid Topical

    MedlinePlus

    Propa pH® Peel-Off Acne Mask ... pimples and skin blemishes in people who have acne. Topical salicylic acid is also used to treat ... medications called keratolytic agents. Topical salicylic acid treats acne by reducing swelling and redness and unplugging blocked ...

  13. Toxicology of Perfluoroalkyl Acids*

    EPA Science Inventory

    The perfluoroalkyl acids (PFAAs) are a family of organic chemicals consisting of a perfluorinated carbon backbone (4-12 in length) and an acidic functional moiety (carboxylate or sulfonate). These compounds are chemically stable, have excellent surface-tension reducing properties...

  14. Mutant fatty acid desaturase

    DOEpatents

    Shanklin, John; Cahoon, Edgar B.

    2004-02-03

    The present invention relates to a method for producing mutants of a fatty acid desaturase having a substantially increased activity towards fatty acid substrates with chains containing fewer than 18 carbons relative to an unmutagenized precursor desaturase having an 18 carbon atom chain length substrate specificity. The method involves inducing one or more mutations in the nucleic acid sequence encoding the precursor desaturase, transforming the mutated sequence into an unsaturated fatty acid auxotroph cell such as MH13 E. coli, culturing the cells in the absence of supplemental unsaturated fatty acids, thereby selecting for recipient cells which have received and which express a mutant fatty acid desaturase with an elevated specificity for fatty acid substrates having chain lengths of less than 18 carbon atoms. A variety of mutants having 16 or fewer carbon atom chain length substrate specificities are produced by this method. Mutant desaturases produced by this method can be introduced via expression vectors into prokaryotic and eukaryotic cells and can also be used in the production of transgenic plants which may be used to produce specific fatty acid products.

  15. Omega-3 Fatty Acids

    MedlinePlus

    Omega-3 fatty acids are used together with lifestyle changes (diet, weight-loss, exercise) to reduce the amount of triglycerides (a fat-like ... people with very high triglycerides. Omega-3 fatty acids are in a class of medications called antilipemic ...

  16. Amino Acid Crossword Puzzle

    ERIC Educational Resources Information Center

    Sims, Paul A.

    2011-01-01

    Learning the 20 standard amino acids is an essential component of an introductory course in biochemistry. Later in the course, the students study metabolism and learn about various catabolic and anabolic pathways involving amino acids. Learning new material or concepts often is easier if one can connect the new material to what one already knows;…

  17. Production of shikimic acid.

    PubMed

    Ghosh, Saptarshi; Chisti, Yusuf; Banerjee, Uttam C

    2012-01-01

    Shikimic acid is a key intermediate for the synthesis of the antiviral drug oseltamivir (Tamiflu®). Shikimic acid can be produced via chemical synthesis, microbial fermentation and extraction from certain plants. An alternative production route is via biotransformation of the more readily available quinic acid. Much of the current supply of shikimic acid is sourced from the seeds of Chinese star anise (Illicium verum). Supply from star anise seeds has experienced difficulties and is susceptible to vagaries of weather. Star anise tree takes around six-years from planting to bear fruit, but remains productive for long. Extraction and purification from seeds are expensive. Production via fermentation is increasing. Other production methods are too expensive, or insufficiently developed. In the future, production in recombinant microorganisms via fermentation may become established as the preferred route. Methods for producing shikimic acid are reviewed.

  18. Basic helix-loop-helix transcription factors JASMONATE-ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3 are negative regulators of jasmonate responses in Arabidopsis.

    PubMed

    Sasaki-Sekimoto, Yuko; Jikumaru, Yusuke; Obayashi, Takeshi; Saito, Hikaru; Masuda, Shinji; Kamiya, Yuji; Ohta, Hiroyuki; Shirasu, Ken

    2013-09-01

    Jasmonates regulate transcriptional reprogramming during growth, development, and defense responses. Jasmonoyl-isoleucine, an amino acid conjugate of jasmonic acid (JA), is perceived by the protein complex composed of the F-box protein CORONATINE INSENSITIVE1 (COI1) and JASMONATE ZIM DOMAIN (JAZ) proteins, leading to the ubiquitin-dependent degradation of JAZ proteins. This activates basic helix-loop-helix-type MYC transcription factors to regulate JA-responsive genes. Here, we show that the expression of genes encoding other basic helix-loop-helix transcription factors, JASMONATE ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3, is positively regulated in a COI1- and MYC2-dependent manner in Arabidopsis (Arabidopsis thaliana). However, contrary to myc2, the jam1jam2jam3 triple mutant exhibited shorter roots when treated with methyl jasmonate (MJ), indicating enhanced responsiveness to JA. Our genome-wide expression analyses revealed that key jasmonate metabolic genes as well as a set of genes encoding transcription factors that regulate the JA-responsive metabolic genes are negatively regulated by JAMs after MJ treatment. Consistently, loss of JAM genes resulted in higher accumulation of anthocyanin in MJ-treated plants as well as higher accumulation of JA and 12-hydroxyjasmonic acid in wounded plants. These results show that JAMs negatively regulate the JA responses in a manner that is mostly antagonistic to MYC2.

  19. Basic Helix-Loop-Helix Transcription Factors JASMONATE-ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3 Are Negative Regulators of Jasmonate Responses in Arabidopsis1[W][OPEN

    PubMed Central

    Sasaki-Sekimoto, Yuko; Jikumaru, Yusuke; Obayashi, Takeshi; Saito, Hikaru; Masuda, Shinji; Kamiya, Yuji; Ohta, Hiroyuki; Shirasu, Ken

    2013-01-01

    Jasmonates regulate transcriptional reprogramming during growth, development, and defense responses. Jasmonoyl-isoleucine, an amino acid conjugate of jasmonic acid (JA), is perceived by the protein complex composed of the F-box protein CORONATINE INSENSITIVE1 (COI1) and JASMONATE ZIM DOMAIN (JAZ) proteins, leading to the ubiquitin-dependent degradation of JAZ proteins. This activates basic helix-loop-helix-type MYC transcription factors to regulate JA-responsive genes. Here, we show that the expression of genes encoding other basic helix-loop-helix transcription factors, JASMONATE ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3, is positively regulated in a COI1- and MYC2-dependent manner in Arabidopsis (Arabidopsis thaliana). However, contrary to myc2, the jam1jam2jam3 triple mutant exhibited shorter roots when treated with methyl jasmonate (MJ), indicating enhanced responsiveness to JA. Our genome-wide expression analyses revealed that key jasmonate metabolic genes as well as a set of genes encoding transcription factors that regulate the JA-responsive metabolic genes are negatively regulated by JAMs after MJ treatment. Consistently, loss of JAM genes resulted in higher accumulation of anthocyanin in MJ-treated plants as well as higher accumulation of JA and 12-hydroxyjasmonic acid in wounded plants. These results show that JAMs negatively regulate the JA responses in a manner that is mostly antagonistic to MYC2. PMID:23852442

  20. Fatty acid production from amino acids and alpha-keto acids by Brevibacterium linens BL2.

    PubMed

    Ganesan, Balasubramanian; Seefeldt, Kimberly; Weimer, Bart C

    2004-11-01

    Low concentrations of branched-chain fatty acids, such as isobutyric and isovaleric acids, develop during the ripening of hard cheeses and contribute to the beneficial flavor profile. Catabolism of amino acids, such as branched-chain amino acids, by bacteria via aminotransferase reactions and alpha-keto acids is one mechanism to generate these flavorful compounds; however, metabolism of alpha-keto acids to flavor-associated compounds is controversial. The objective of this study was to determine the ability of Brevibacterium linens BL2 to produce fatty acids from amino acids and alpha-keto acids and determine the occurrence of the likely genes in the draft genome sequence. BL2 catabolized amino acids to fatty acids only under carbohydrate starvation conditions. The primary fatty acid end products from leucine were isovaleric acid, acetic acid, and propionic acid. In contrast, logarithmic-phase cells of BL2 produced fatty acids from alpha-keto acids only. BL2 also converted alpha-keto acids to branched-chain fatty acids after carbohydrate starvation was achieved. At least 100 genes are potentially involved in five different metabolic pathways. The genome of B. linens ATCC 9174 contained these genes for production and degradation of fatty acids. These data indicate that brevibacteria have the ability to produce fatty acids from amino and alpha-keto acids and that carbon metabolism is important in regulating this event.

  1. Total syntheses of cis-cyclopropane fatty acids: dihydromalvalic acid, dihydrosterculic acid, lactobacillic acid, and 9,10-methylenehexadecanoic acid.

    PubMed

    Shah, Sayali; White, Jonathan M; Williams, Spencer J

    2014-12-14

    cis-Cyclopropane fatty acids (cis-CFAs) are widespread constituents of the seed oils of subtropical plants, membrane components of bacteria and protozoa, and the fats and phospholipids of animals. We describe a systematic approach to the synthesis of enantiomeric pairs of four cis-CFAs: cis-9,10-methylenehexadecanoic acid, lactobacillic acid, dihydromalvalic acid, and dihydrosterculic acid. The approach commences with Rh2(OAc)4-catalyzed cyclopropenation of 1-octyne and 1-decyne, and hinges on the preparative scale chromatographic resolution of racemic 2-alkylcycloprop-2-ene-1-carboxylic acids using a homochiral Evan's auxiliary. Saturation of the individual diastereomeric N-cycloprop-2-ene-1-carbonylacyloxazolidines, followed by elaboration to alkylcyclopropylmethylsulfones, allowed Julia-Kocienski olefination with various ω-aldehyde-esters. Finally, saponification and diimide reduction afforded the individual cis-CFA enantiomers.

  2. Jasmonic acid and salicylic acid inhibit growth of three sugarbeet storage rot pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Storage rots contribute to postharvest losses by consuming sucrose and increasing carbohydrate impurities that increase sugar loss to molasses during processing. They also increase root respiration rate, which causes additional sucrose loss and contributes to pile warming. Currently, storage rots ...

  3. Control of storage rot by induction of plant defense mechanisms using jasmonic acid and salicylic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Storage rots contribute to sugarbeet postharvest losses by consuming sucrose and producing carbohydrate impurities that increase sugar loss to molasses. Presently, storage rots are controlled by cooling storage piles. This method of control, however, requires favorable weather conditions for stora...

  4. Defense against Sclerotinia sclerotiorum in Arabidopsis is dependent on jasmonic acid, salicylic acid, and ethylene signaling.

    PubMed

    Guo, Xiaomei; Stotz, Henrik U

    2007-11-01

    Genotypic differences in susceptibility of Arabidopsis thaliana to Sclerotinia sclerotiorum have not been reported due to the extreme susceptibility of this cruciferous plant. To overcome this limitation, we have established inoculation conditions that enable evaluation of differences in susceptibility to S. sclerotiorum among Arabidopsis mutants and ecotypes. Two coil mutant alleles conferred hypersusceptibility to S. sclerotiorum. The plant defensin gene PDF1.2 was no longer induced after challenging the coi1-2 mutant with S. sclerotiorum. Hypersusceptibility of the coi1-2 mutant to S. sclerotiorum was not correlated with oxalate sensitivity. The mutants npr1 and ein2 were also hypersusceptible to S. sclerotiorum. Induction of PDF1.2 and the pathogenesis-related gene PR1 was reduced in ein2 and npr1 mutants, respectively. Actigard, a commercial formulation of the systemic acquired resistance inducer benzothiadiazole, reduced susceptibility to S. sclerotiorum. Based on histochemical analysis of oxalate-deficient and wild-type strains of S. sclerotiorum, oxalate caused a decrease in hydrogen peroxide production but no detectable changes in plant superoxide production or gene expression.

  5. Sulfuric Acid on Europa

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Frozen sulfuric acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high frozen sulfuric acid concentration. Sulfuric acid is found in battery acid and in Earth's acid rain.

    This image is based on data gathered by Galileo's near infrared mapping spectrometer.

    Europa's leading hemisphere is toward the bottom right, and there are enhanced concentrations of sulfuric acid in the trailing side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that crisscross Europa also show sulfuric acid that may be from sulfurous material extruded in cracks.

    Galileo, launched in 1989, has been orbiting Jupiter and its moons since December 1995. JPL manages the Galileo mission for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

  6. Trans Fatty Acids

    NASA Astrophysics Data System (ADS)

    Doyle, Ellin

    1997-09-01

    Fats and their various fatty acid components seem to be a perennial concern of nutritionists and persons concerned with healthful diets. Advice on the consumption of saturated, polyunsaturated, monounsaturated, and total fat bombards us from magazines and newspapers. One of the newer players in this field is the group of trans fatty acids found predominantly in partially hydrogenated fats such as margarines and cooking fats. The controversy concerning dietary trans fatty acids was recently addressed in an American Heart Association (AHA) science advisory (1) and in a position paper from the American Society of Clinical Nutrition/American Institute of Nutrition (ASCN/AIN) (2). Both reports emphasize that the best preventive strategy for reducing risk for cardiovascular disease and some types of cancer is a reduction in total and saturated fats in the diet, but a reduction in the intake of trans fatty acids was also recommended. Although the actual health effects of trans fatty acids remain uncertain, experimental evidence indicates that consumption of trans fatty acids adversely affects serum lipid levels. Since elevated levels of serum cholesterol and triacylglycerols are associated with increased risk of cardiovascular disease, it follows that intake of trans fatty acids should be minimized.

  7. Gluconic acid production.

    PubMed

    Anastassiadis, Savas; Morgunov, Igor G

    2007-01-01

    Gluconic acid, the oxidation product of glucose, is a mild neither caustic nor corrosive, non toxic and readily biodegradable organic acid of great interest for many applications. As a multifunctional carbonic acid belonging to the bulk chemicals and due to its physiological and chemical characteristics, gluconic acid itself, its salts (e.g. alkali metal salts, in especially sodium gluconate) and the gluconolactone form have found extensively versatile uses in the chemical, pharmaceutical, food, construction and other industries. Present review article presents the comprehensive information of patent bibliography for the production of gluconic acid and compares the advantages and disadvantages of known processes. Numerous manufacturing processes are described in the international bibliography and patent literature of the last 100 years for the production of gluconic acid from glucose, including chemical and electrochemical catalysis, enzymatic biocatalysis by free or immobilized enzymes in specialized enzyme bioreactors as well as discontinuous and continuous fermentation processes using free growing or immobilized cells of various microorganisms, including bacteria, yeast-like fungi and fungi. Alternatively, new superior fermentation processes have been developed and extensively described for the continuous and discontinuous production of gluconic acid by isolated strains of yeast-like mold Aureobasidium pullulans, offering numerous advantages over the traditional discontinuous fungi processes.

  8. Strongly Acidic Auxin Indole-3-Methanesulfonic Acid

    PubMed Central

    Cohen, Jerry D.; Baldi, Bruce G.; Bialek, Krystyna

    1985-01-01

    A radiochemical synthesis is described for [14C]indole-3-methanesulfonic acid (IMS), a strongly acidic auxin analog. Techniques were developed for fractionation and purification of IMS using normal and reverse phase chromatography. In addition, the utility of both Fourier transform infrared spectrometry and fast atom bombardment mass spectrometry for analysis of IMS has been demonstrated. IMS was shown to be an active auxin, stimulating soybean hypocotyl elongation, bean first internode curvature, and ethylene production. IMS uptake by thin sections of soybean hypocotyl was essentially independent of solution pH and, when applied at a 100 micromolar concentration, IMS exhibited a basipetal polarity in its transport in both corn coleoptile and soybean hypocotyl sections. [14C]IMS should, therefore, be a useful compound to study fundamental processes related to the movement of auxins in plant tissues and organelles. PMID:16664007

  9. Wound and insect-induced jasmonate accumulation in carnivorous Drosera capensis: two sides of the same coin.

    PubMed

    Mithöfer, A; Reichelt, M; Nakamura, Y

    2014-09-01

    Carnivorous sundew plants catch and digest insect prey for their own nutrition. The sundew species Drosera capensis shows a pronounced leaf bending reaction upon prey capture in order to form an 'outer stomach'. This formation is triggered by jasmonates, phytohormones typically involved in defence reactions against herbivory and wounding. Whether jasmonates still have this function in D. capensis in addition to mediating the leaf bending reaction was investigated here. Wounded, insect prey-fed and insect-derived oral secretion-treated leaves of D. capensis were analysed for jasmonates (jasmonic acid, JA; jasmonic acid-isoleucine conjugate, JA-Ile) using LC-MS/MS. Prey-induced jasmonate accumulation in D. capensis leaves was persistent, and showed high levels of JA and JA-Ile (575 and 55.7 pmol · g · FW(-1) , respectively), whereas wounding induced a transient increase of JA (maximum 500 pmol · g · FW(-1) ) and only low (3.1 pmol · g · FW(-1) ) accumulation of JA-Ile. Herbivory, mimicked with a combined treatment of wounding plus oral secretion (W+OS) obtained from Spodoptera littoralis larvae induced both JA (4000 pmol · g · FW(-1) ) and JA-Ile (25 pmol · g · FW(-1) ) accumulation, with kinetics similar to prey treatment. Only prey and W+OS, but not wounding alone or OS, induced leaf bending. The results indicate that both mechanical and chemical stimuli trigger JA and JA-Ile synthesis. Differences in kinetics and induced jasmonate levels suggest different sensing and signalling events upon injury and insect-dependent challenge. Thus, in Drosera, jasmonates are still part of the response to wounding. Jasmonates are also employed in insect-induced reactions, including responses to herbivory and carnivory.

  10. Jasmonates: Multifunctional Roles in Stress Tolerance

    PubMed Central

    Ahmad, Parvaiz; Rasool, Saiema; Gul, Alvina; Sheikh, Subzar A.; Akram, Nudrat A.; Ashraf, Muhammad; Kazi, A. M.; Gucel, Salih

    2016-01-01

    Jasmonates (JAs) [Jasmonic acid (JA) and methyl jasmonates (MeJAs)] are known to take part in various physiological processes. Exogenous application of JAs so far tested on different plants under abiotic stresses particularly salinity, drought, and temperature (low/high) conditions have proved effective in improving plant stress tolerance. However, its extent of effectiveness entirely depends on the type of plant species tested or its concentration. The effects of introgression or silencing of different JA- and Me-JA-related genes have been summarized in this review, which have shown a substantial role in improving crop yield and quality in different plants under stress or non-stress conditions. Regulation of JAs synthesis is impaired in stressed as well as unstressed plant cells/tissues, which is believed to be associated with a variety of metabolic events including signal transduction. Although, mitogen activated protein kinases (MAPKs) are important components of JA signaling and biosynthesis pathways, nitric oxide, ROS, calcium, ABA, ethylene, and salicylic acid are also important mediators of plant growth and development during JA signal transduction and synthesis. The exploration of other signaling molecules can be beneficial to examine the details of underlying molecular mechanisms of JA signal transduction. Much work is to be done in near future to find the proper answers of the questions like action of JA related metabolites, and identification of universal JA receptors etc. Complete signaling pathways involving MAPKs, CDPK, TGA, SIPK, WIPK, and WRKY transcription factors are yet to be investigated to understand the complete mechanism of action of JAs. PMID:27379115

  11. Aminolevulinic Acid Topical

    MedlinePlus

    ... under the skin that result from exposure to sunlight and can develop into skin cancer) of the ... acid will make your skin very sensitive to sunlight (likely to get sunburn). Avoid exposure of treated ...

  12. Difficult Decisions: Acid Rain.

    ERIC Educational Resources Information Center

    Miller, John A.; Slesnick, Irwin L.

    1989-01-01

    Discusses some of the contributing factors and chemical reactions involved in the production of acid rain, its effects, and political issues pertaining to who should pay for the clean up. Supplies questions for consideration and discussion. (RT)

  13. Folic acid - test

    MedlinePlus

    ... folic acid before and during pregnancy helps prevent neural tube defects, such as spina bifida. Women who ... take more if they have a history of neural tube defects in earlier pregnancies. Ask your provider ...

  14. Acid soldering flux poisoning

    MedlinePlus

    The harmful substances in soldering fluxes are called hydrocarbons. They include: Ammonium chloride Rosin Hydrochloric acid Zinc ... Lee DC. Hydrocarbons. In: Marx JA, Hockberger RS, Walls RM, et ... Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ...

  15. Amoxicillin and Clavulanic Acid

    MedlinePlus

    ... Amoxicillin is in a class of medications called penicillin-like antibiotics. It works by stopping the growth ... allergic to amoxicillin (Amoxil, Trimox, Wymox), clavulanic acid, penicillin, cephalosporins, or any other medications.tell your doctor ...

  16. Amino Acid Metabolism Disorders

    MedlinePlus

    ... acidemia? In ASA, the body can’t remove ammonia or a substance called argininosuccinic acid from the ... and children include: Breathing problems High levels of ammonia in the bloodIntense headache, especially after a high- ...

  17. [Hydrofluoric acid burns].

    PubMed

    Holla, Robin; Gorter, Ramon R; Tenhagen, Mark; Vloemans, A F P M Jos; Breederveld, Roelf S

    2016-01-01

    Hydrofluoric acid is increasingly used as a rust remover and detergent. Dermal contact with hydrofluoric acid results in a chemical burn characterized by severe pain and deep tissue necrosis. It may cause electrolyte imbalances with lethal consequences. It is important to identify high-risk patients. 'High risk' is defined as a total affected body area > 3% or exposure to hydrofluoric acid in a concentration > 50%. We present the cases of three male patients (26, 31, and 39 years old) with hydrofluoric acid burns of varying severity and describe the subsequent treatments. The application of calcium gluconate 2.5% gel to the skin is the cornerstone of the treatment, reducing pain as well as improving wound healing. Nails should be thoroughly inspected and possibly removed if the nail is involved, to ensure proper healing. In high-risk patients, plasma calcium levels should be evaluated and cardiac monitoring is indicated.

  18. Citric acid urine test

    MedlinePlus

    ... used to diagnose renal tubular acidosis and evaluate kidney stone disease. Normal Results The normal range is 320 ... tubular acidosis and a tendency to form calcium kidney stones. The following may decrease urine citric acid levels: ...

  19. Lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Bullock, Kathryn R.

    Lead/acid batteries are produced in sizes from less than 1 to 3000 Ah for a wide variety of portable, industrial and automotive applications. Designs include Planté, Fauré or pasted, and tubular electrodes. In addition to the traditional designs which are flooded with sulfuric acid, newer 'valve-regulated" designs have the acid immolibized in a silica gel or absorbed in a porous glass separator. Development is ongoing worldwide to increase the specific power, energy and deep discharge cycle life of this commercially successful system to meet the needs of new applications such as electric vehicles, load leveling, and solar energy storage. The operating principles, current status, technical challenges and commercial impact of the lead/acid battery are reviewed.

  20. Amino Acids and Chirality

    NASA Technical Reports Server (NTRS)

    Cook, Jamie E.

    2012-01-01

    Amino acids are among the most heavily studied organic compound class in carbonaceous chondrites. The abundance, distributions, enantiomeric compositions, and stable isotopic ratios of amino acids have been determined in carbonaceous chondrites fi'om a range of classes and petrographic types, with interesting correlations observed between these properties and the class and typc of the chondritcs. In particular, isomeric distributions appear to correlate with parent bodies (chondrite class). In addition, certain chiral amino acids are found in enantiomeric excess in some chondrites. The delivery of these enantiomeric excesses to the early Earth may have contributed to the origin of the homochirality that is central to life on Earth today. This talk will explore the amino acids in carbonaceous chondritcs and their relevance to the origin of life.

  1. The linoleic acid and trans fatty acids of margarines.

    PubMed

    Beare-Rogers, J L; Gray, L M; Hollywood, R

    1979-09-01

    Fifty brands of margarine were analysed for cis-polyunsaturated acids by lipoxidase, for trans fatty acid by infared spectroscopy, and for fatty acid composition by gas-liquid chromatography. High concentrations of trans fatty acids tended to be associated with low concentrations of linoleic acid. Later analyses on eight of the brands, respresenting various proportions of linoleic to trans fatty acids, indicated that two of them contained still higher levels of trans fatty acids (greater than 60%) and negligible amounts of linoleic acid. It is proposed that margarine could be a vehicle for the distribution of some dietary linoleic acid and that the level of linoleic acid and the summation of the saturated plus trans fatty acids be known to ascertain nutritional characteristics.

  2. Method for isolating nucleic acids

    SciTech Connect

    Hurt, Jr., Richard Ashley; Elias, Dwayne A.

    2015-09-29

    The current disclosure provides methods and kits for isolating nucleic acid from an environmental sample. The current methods and compositions further provide methods for isolating nucleic acids by reducing adsorption of nucleic acids by charged ions and particles within an environmental sample. The methods of the current disclosure provide methods for isolating nucleic acids by releasing adsorbed nucleic acids from charged particles during the nucleic acid isolation process. The current disclosure facilitates the isolation of nucleic acids of sufficient quality and quantity to enable one of ordinary skill in the art to utilize or analyze the isolated nucleic acids for a wide variety of applications including, sequencing or species population analysis.

  3. [Acids in coffee. XI. The proportion of individual acids in the total titratable acid].

    PubMed

    Engelhardt, U H; Maier, H G

    1985-07-01

    22 acids in ground roast coffees and instant coffees were determined by GLC of their silyl derivatives (after preseparation by gel electrophoresis) or isotachophoresis. The contribution to the total acidity (which was estimated by titration to pH 8 after cation exchange of the coffee solutions) was calculated for each individual acid. The mentioned acids contribute with 67% (roast coffee) and 72% (instant coffee) to the total acidity. In the first place citric acid (12.2% in roast coffee/10.7% in instant coffee), acetic acid (11.2%/8.8%) and the high molecular weight acids (8%/9%) contribute to the total acidity. Also to be mentioned are the shares of chlorogenic acids (9%/4.8%), formic acid (5.3%/4.6%), quinic acid (4.7%/5.9%), malic acid (3.9%/3%) and phosphoric acid (2.5%/5.2%). A notable difference in the contribution to total acidity between roast and instant coffee was found for phosphoric acid and pyrrolidonecarboxylic acid (0.7%/1.9%). It can be concluded that those two acids are formed or released from e.g. their esters in higher amounts than other acids during the production of instant coffee.

  4. Acidification and Acid Rain

    NASA Astrophysics Data System (ADS)

    Norton, S. A.; Veselã½, J.

    2003-12-01

    Air pollution by acids has been known as a problem for centuries (Ducros, 1845; Smith, 1872; Camuffo, 1992; Brimblecombe, 1992). Only in the mid-1900s did it become clear that it was a problem for more than just industrially developed areas, and that precipitation quality can affect aquatic resources ( Gorham, 1955). The last three decades of the twentieth century saw tremendous progress in the documentation of the chemistry of the atmosphere, precipitation, and the systems impacted by acid atmospheric deposition. Chronic acidification of ecosystems results in chemical changes to soil and to surface waters and groundwater as a result of reduction of base cation supply or an increase in acid (H+) supply, or both. The most fundamental changes during chronic acidification are an increase in exchangeable H+ or Al3+ (aluminum) in soils, an increase in H+ activity (˜concentration) in water in contact with soil, and a decrease in alkalinity in waters draining watersheds. Water draining from the soil is acidified and has a lower pH (=-log [H+]). As systems acidify, their biotic community changes.Acidic surface waters occur in many parts of the world as a consequence of natural processes and also due to atmospheric deposition of strong acid (e.g., Canada, Jeffries et al. (1986); the United Kingdom, Evans and Monteith (2001); Sweden, Swedish Environmental Protection Board (1986); Finland, Forsius et al. (1990); Norway, Henriksen et al. (1988a); and the United States (USA), Brakke et al. (1988)). Concern over acidification in the temperate regions of the northern hemisphere has been driven by the potential for accelerating natural acidification by pollution of the atmosphere with acidic or acidifying compounds. Atmospheric pollution ( Figure 1) has resulted in an increased flux of acid to and through ecosystems. Depending on the ability of an ecosystem to neutralize the increased flux of acidity, acidification may increase only imperceptibly or be accelerated at a rate that

  5. The second acidic constant of salicylic acid.

    PubMed

    Porto, Raffaella; De Tommaso, Gaetano; Furia, Emilia

    2005-01-01

    The second dissociation constant of salicylic acid (H2L) has been determined, at 25 degrees C, in NaCl ionic media by UV spectrophotometric measurements. The investigated ionic strength values were 0.16, 0.25, 0.50, 1.0, 2.0 and 3.0 M. The protolysis constants calculated at the different ionic strengths yielded, with the Specific Interaction Theory, the infinite dilution constant, log beta1(0) = 13.62 +/- 0.03, for the equilibrium L2- + H+ <==> HL-. The interaction coefficient between Na+ and L2-, b(Na+, L2-) = 0.02 +/- 0.07, has been also calculated.

  6. Differential activation of pregnane X receptor by carnosic acid, carnosol, ursolic acid, and rosmarinic acid.

    PubMed

    Seow, Chun Ling; Lau, Aik Jiang

    2017-03-10

    Pregnane X receptor (PXR) regulates the expression of many genes, including those involved in drug metabolism and transport, and has been linked to various diseases, including inflammatory bowel disease. In the present study, we determined whether carnosic acid and other chemicals in rosemary extract (carnosol, ursolic acid, and rosmarinic acid) are PXR activators. As assessed in dual-luciferase reporter gene assays, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, activated human PXR (hPXR) and mouse PXR (mPXR), whereas carnosol and ursolic acid, but not carnosic acid or rosmarinic acid, activated rat PXR (rPXR). Dose-response experiments indicated that carnosic acid, carnosol, and ursolic acid activated hPXR with EC50 values of 0.79, 2.22, and 10.77μM, respectively. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, transactivated the ligand-binding domain of hPXR and recruited steroid receptor coactivator-1 (SRC-1), SRC-2, and SRC-3 to the ligand-binding domain of hPXR. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, increased hPXR target gene expression, as shown by an increase in CYP3A4, UGT1A3, and ABCB1 mRNA expression in LS180 human colon adenocarcinoma cells. Rosmarinic acid did not attenuate the extent of hPXR activation by rifampicin, suggesting it is not an antagonist of hPXR. Overall, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, are hPXR agonists, and carnosic acid shows species-dependent activation of hPXR and mPXR, but not rPXR. The findings provide new mechanistic insight on the effects of carnosic acid, carnosol, and ursolic acid on PXR-mediated biological effects.

  7. Jasmonates: Emerging Players in Controlling Temperature Stress Tolerance.

    PubMed

    Sharma, Manvi; Laxmi, Ashverya

    2015-01-01

    The sedentary life of plants has forced them to live in an environment that is characterized by the presence of numerous challenges in terms of biotic and abiotic stresses. Phytohormones play essential roles in mediating plant physiology and alleviating various environmental perturbations. Jasmonates are a group of oxylipin compounds occurring ubiquitously in the plant kingdom that play pivotal roles in response to developmental and environmental cues. Jasmonates (JAs) have been shown to participate in unison with key factors of other signal transduction pathway, including those involved in response to abiotic stress. Recent findings have furnished large body of information suggesting the role of jasmonates in cold and heat stress. JAs have been shown to regulate C-repeat binding factor (CBF) pathway during cold stress. The interaction between the integrants of JA signaling and components of CBF pathway demonstrates a complex relationship between the two. JAs have also been shown to counteract chilling stress by inducing ROS avoidance enzymes. In addition, several lines of evidence suggest the positive regulation of thermotolerance by JA. The present review provides insights into biosynthesis, signal transduction pathway of jasmonic acid and their role in response to temperature stress.

  8. Jasmonates: Emerging Players in Controlling Temperature Stress Tolerance

    PubMed Central

    Sharma, Manvi; Laxmi, Ashverya

    2016-01-01

    The sedentary life of plants has forced them to live in an environment that is characterized by the presence of numerous challenges in terms of biotic and abiotic stresses. Phytohormones play essential roles in mediating plant physiology and alleviating various environmental perturbations. Jasmonates are a group of oxylipin compounds occurring ubiquitously in the plant kingdom that play pivotal roles in response to developmental and environmental cues. Jasmonates (JAs) have been shown to participate in unison with key factors of other signal transduction pathway, including those involved in response to abiotic stress. Recent findings have furnished large body of information suggesting the role of jasmonates in cold and heat stress. JAs have been shown to regulate C-repeat binding factor (CBF) pathway during cold stress. The interaction between the integrants of JA signaling and components of CBF pathway demonstrates a complex relationship between the two. JAs have also been shown to counteract chilling stress by inducing ROS avoidance enzymes. In addition, several lines of evidence suggest the positive regulation of thermotolerance by JA. The present review provides insights into biosynthesis, signal transduction pathway of jasmonic acid and their role in response to temperature stress. PMID:26779205

  9. Discovery of essential fatty acids

    PubMed Central

    Spector, Arthur A.; Kim, Hee-Yong

    2015-01-01

    Dietary fat was recognized as a good source of energy and fat-soluble vitamins by the first part of the 20th century, but fatty acids were not considered to be essential nutrients because they could be synthesized from dietary carbohydrate. This well-established view was challenged in 1929 by George and Mildred Burr who reported that dietary fatty acid was required to prevent a deficiency disease that occurred in rats fed a fat-free diet. They concluded that fatty acids were essential nutrients and showed that linoleic acid prevented the disease and is an essential fatty acid. The Burrs surmised that other unsaturated fatty acids were essential and subsequently demonstrated that linolenic acid, the omega-3 fatty acid analog of linoleic acid, is also an essential fatty acid. The discovery of essential fatty acids was a paradigm-changing finding, and it is now considered to be one of the landmark discoveries in lipid research. PMID:25339684

  10. Acid Rain, pH & Acidity: A Common Misinterpretation.

    ERIC Educational Resources Information Center

    Clark, David B.; Thompson, Ronald E.

    1989-01-01

    Illustrates the basis for misleading statements about the relationship between pH and acid content in acid rain. Explains why pH cannot be used as a measure of acidity for rain or any other solution. Suggests that teachers present acidity and pH as two separate and distinct concepts. (RT)

  11. [Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis].

    PubMed

    Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua

    2016-03-01

    Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis.

  12. Continuous exposure to the deterrents cis-jasmone and methyl jasmonate does not alter the behavioural responses of Frankliniella occidentalis

    PubMed Central

    Egger, Barbara; Spangl, Bernhard; Koschier, Elisabeth Helene

    2016-01-01

    Behavioural responses of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), a generalist, cell sap-feeding insect species with piercing-sucking mouthparts, after continuous exposure to two deterrent secondary plant compounds are investigated. We compared in choice assays on bean leaf discs, the settling, feeding, and oviposition preferences of F. occidentalis females that had no experience with the two fatty acid derivatives methyl jasmonate and cis-jasmone before testing (naïve thrips) vs. females that had been exposed to the deterrent compounds before testing (experienced thrips). The thrips were exposed to the deterrents at low or high concentrations for varied time periods and subsequently tested on bean leaf discs treated with the respective deterrent at either a low or a high concentration. Frankliniella occidentalis females avoided settling on the deterrent-treated bean leaf discs for an observation period of 6 h, independent of their previous experience. Our results demonstrate that feeding and oviposition deterrence of the jasmonates to the thrips were not altered by continuous exposure of the thrips to the jasmonates. Habituation was not induced, neither by exposure to the low concentration of the deterrents nor by exposure to the high concentration. These results indicate that the risk of habituation to two volatile deterrent compounds after repeated exposure is not evident in F. occidentalis. This makes the two compounds potential candidates to be integrated in pest management strategies. PMID:26726263

  13. Amino-acid contamination of aqueous hydrochloric acid.

    NASA Technical Reports Server (NTRS)

    Wolman, Y.; Miller, S. L.

    1971-01-01

    Considerable amino-acid contamination in commercially available analytical grade hydrochloric acid (37% HCl) was found. One bottle contained 8,300 nmol of amino-acids per liter. A bottle from another supplier contained 6,700 nmol per liter. The contaminants were mostly protein amino-acids and several unknowns. Data on the volatility of the amino-acids during HCl distillation were also obtained.

  14. Recurrent uric acid stones.

    PubMed

    Kamel, K S; Cheema-Dhadli, S; Shafiee, M A; Davids, M R; Halperin, M L

    2005-01-01

    A 46-year-old female had a history of recurrent uric acid stone formation, but the reason why uric acid precipitated in her urine was not obvious, because the rate of urate excretion was not high, urine volume was not low, and the pH in her 24-h urine was not low enough. In his discussion of the case, Professor McCance provided new insights into the pathophysiology of uric acid stone formation. He illustrated that measuring the pH in a 24-h urine might obscure the fact that the urine pH was low enough to cause uric acid to precipitate during most of the day. Because he found a low rate of excretion of NH(4)(+) relative to that of sulphate anions, as well as a high rate of citrate excretion, he speculated that the low urine pH would be due to a more alkaline pH in proximal convoluted tubule cells. He went on to suspect that there was a problem in our understanding of the function of renal medullary NH(3) shunt pathway, and he suggested that its major function might be to ensure a urine pH close to 6.0 throughout the day, to minimize the likelihood of forming uric acid kidney stones.

  15. Jasmonoyl isoleucine accumulation is needed for abscisic acid build-up in roots of Arabidopsis under water stress conditions.

    PubMed

    de Ollas, Carlos; Arbona, Vicent; Gómez-Cadenas, Aurelio

    2015-10-01

    Phytohormones are central players in sensing and signalling numerous environmental conditions like drought. In this work, hormone profiling together with gene expression of key enzymes involved in abscisic acid (ABA) and jasmonate biosynthesis were studied in desiccating Arabidopsis roots. Jasmonic acid (JA) content transiently increased after stress imposition whereas progressive and concomitant ABA and Jasmonoyl Isoleucine (JA-Ile) accumulations were detected. Molecular data suggest that, at least, part of the hormonal regulation takes place at the biosynthetic level. These observations also point to a possible involvement of jasmonates on ABA biosynthesis under stress. To test this hypothesis, mutants impaired in jasmonate biosynthesis (opr3, lox6 and jar1-1) and in JA-dependent signalling (coi1) were employed. Results showed that the early JA accumulation leading to JA-Ile build up was necessary for an ABA increase in roots under two different water stress conditions. Signal transduction between water stress-induced JA-Ile accumulation and COI1 is necessary for a full induction of the ABA biosynthesis pathway and subsequent hormone accumulation in roots of Arabidopsis plants. The present work adds a level of interaction between jasmonates and ABA at the biosynthetic level.

  16. Hydrogen production by fermentation using acetic acid and lactic acid.

    PubMed

    Matsumoto, Mitsufumi; Nishimura, Yasuhiko

    2007-03-01

    Microbial hydrogen production from sho-chu post-distillation slurry solution (slurry solution) containing large amounts of organic acids was investigated. The highest hydrogen producer, Clostridium diolis JPCC H-3, was isolated from natural environment and produced hydrogen at 6.03+/-0.15 ml from 5 ml slurry solution in 30 h. Interestingly, the concentration of acetic acid and lactic acid in the slurry solution decreased during hydrogen production. The substrates for hydrogen production by C. diolis JPCC H-3, in particular organic acids, were investigated in an artificial medium. No hydrogen was produced from acetic acid, propionic acid, succinic acid, or citric acid on their own. Hydrogen and butyric acid were produced from a mixture of acetic acid and lactic acid, showing that C. diolis. JPCC H-3 could produce hydrogen from acetic acid and lactic acid. Furthermore, calculation of the Gibbs free energy strongly suggests that this reaction would proceed. In this paper, we describe for the first time microbial hydrogen production from acetic acid and lactic acid by fermentation.

  17. A Demonstration of Acid Rain

    ERIC Educational Resources Information Center

    Fong, Man Wai

    2004-01-01

    A demonstration showing acid rain formation is described. Oxides of sulfur and nitrogen that result from the burning of fossil fuels are the major pollutants of acid rain. In this demonstration, SO[subscript 2] gas is produced by the burning of matches. An acid-base indicator will show that the dissolved gas turns an aqueous solution acidic.

  18. Biodegradation of Cyanuric Acid

    PubMed Central

    Saldick, Jerome

    1974-01-01

    Cyanuric acid biodegrades readily under a wide variety of natural conditions, and particularly well in systems of either low or zero dissolved-oxygen level, such as anaerobic activated sludge and sewage, soils, muds, and muddy streams and river waters, as well as ordinary aerated activated sludge systems with typically low (1 to 3 ppm) dissolved-oxygen levels. Degradation also proceeds in 3.5% sodium chloride solution. Consequently, there are degradation pathways widely available for breaking down cyanuric acid discharged in domestic effluents. The overall degradation reaction is merely a hydrolysis; CO2 and ammonia are the initial hydrolytic breakdown products. Since no net oxidation occurs during this breakdown, biodegradation of cyanuric acid exerts no primary biological oxygen demand. However, eventual nitrification of the ammonia released will exert its usual biological oxygen demand. PMID:4451360

  19. [Aristolochic acid nephropathy].

    PubMed

    Witkowicz, Joanna

    2009-01-01

    Aristolochic acid nephropathy is a chronic, fibrosing, interstitial nephritis caused by aristolochic acid (AA), which is a component of the plants of Aristolochiacae family. It was first reported in 1993, in Belgium as a Chinese herb nephropathy, in patients who received a slimming regimen containing AA. The term aristolochic acid nephropathy also includes Balcan endemic nephropathy and other endemic tubulointerstitial fibrosis. Moreover, AA is a human carcinogen which induces urothelial cancer. The AA-containing herbs are banned in many countries and FDA published the warnings concerning the safety of AA-containing botanical remedies in 2000. Regarding the increasing interest in herbal medicines, uncontrolled access to botanical remedies and replacement of one herb by another AA-containing compounds makes thousands of people all around the world at risk of this grave disease.

  20. Differential Impact of Lipoxygenase 2 and Jasmonates on Natural and Stress-Induced Senescence in Arabidopsis1[W

    PubMed Central

    Seltmann, Martin A.; Stingl, Nadja E.; Lautenschlaeger, Jens K.; Krischke, Markus; Mueller, Martin J.; Berger, Susanne

    2010-01-01

    Jasmonic acid and related oxylipins are controversially discussed to be involved in regulating the initiation and progression of leaf senescence. To this end, we analyzed profiles of free and esterified oxylipins during natural senescence and upon induction of senescence-like phenotypes by dark treatment and flotation on sorbitol in Arabidopsis (Arabidopsis thaliana). Jasmonic acid and free 12-oxo-phytodienoic acid increased during all three processes, with the strongest increase of jasmonic acid after dark treatment. Arabidopside content only increased considerably in response to sorbitol treatment. Monogalactosyldiacylglycerols and digalactosyldiacylglycerols decreased during these treatments and aging. Lipoxygenase 2-RNA interference (RNAi) plants were generated, which constitutively produce jasmonic acid and 12-oxo-phytodienoic acid but do not exhibit accumulation during natural senescence or upon stress treatment. Chlorophyll loss during aging and upon dark incubation was not altered, suggesting that these oxylipins are not involved in these processes. In contrast, lipoxygenase 2-RNAi lines and the allene oxid synthase-deficient mutant dde2 were less sensitive to sorbitol than the wild type, indicating that oxylipins contribute to the response to sorbitol stress. PMID:20190093

  1. Calorimetry of Nucleic Acids.

    PubMed

    Rozners, Eriks; Pilch, Daniel S; Egli, Martin

    2015-12-01

    This unit describes the application of calorimetry to characterize the thermodynamics of nucleic acids, specifically, the two major calorimetric methodologies that are currently employed: differential scanning (DSC) and isothermal titration calorimetry (ITC). DSC is used to study thermally induced order-disorder transitions in nucleic acids. A DSC instrument measures, as a function of temperature (T), the excess heat capacity (C(p)(ex)) of a nucleic acid solution relative to the same amount of buffer solution. From a single curve of C(p)(ex) versus T, one can derive the following information: the transition enthalpy (ΔH), entropy (ΔS), free energy (ΔG), and heat capacity (ΔCp); the state of the transition (two-state versus multistate); and the average size of the molecule that melts as a single thermodynamic entity (e.g., the duplex). ITC is used to study the hybridization of nucleic acid molecules at constant temperature. In an ITC experiment, small aliquots of a titrant nucleic acid solution (strand 1) are added to an analyte nucleic acid solution (strand 2), and the released heat is monitored. ITC yields the stoichiometry of the association reaction (n), the enthalpy of association (ΔH), the equilibrium association constant (K), and thus the free energy of association (ΔG). Once ΔH and ΔG are known, ΔS can also be derived. Repetition of the ITC experiment at a number of different temperatures yields the ΔCp for the association reaction from the temperature dependence of ΔH.

  2. Acid rain in Asia

    NASA Astrophysics Data System (ADS)

    Bhatti, Neeloo; Streets, David G.; Foell, Wesley K.

    1992-07-01

    Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world.

  3. Ethylenediaminetetraacetic acid in endodontics.

    PubMed

    Mohammadi, Zahed; Shalavi, Sousan; Jafarzadeh, Hamid

    2013-09-01

    Ethylenediaminetetraacetic acid (EDTA) is a chelating agent can bind to metals via four carboxylate and two amine groups. It is a polyamino carboxylic acid and a colorless, water-soluble solid, which is widely used to dissolve lime scale. It is produced as several salts, notably disodium EDTA and calcium disodium EDTA. EDTA reacts with the calcium ions in dentine and forms soluble calcium chelates. A review of the literature and a discussion of the different indications and considerations for its usage are presented.

  4. Ethylenediaminetetraacetic acid in endodontics

    PubMed Central

    Mohammadi, Zahed; Shalavi, Sousan; Jafarzadeh, Hamid

    2013-01-01

    Ethylenediaminetetraacetic acid (EDTA) is a chelating agent can bind to metals via four carboxylate and two amine groups. It is a polyamino carboxylic acid and a colorless, water-soluble solid, which is widely used to dissolve lime scale. It is produced as several salts, notably disodium EDTA and calcium disodium EDTA. EDTA reacts with the calcium ions in dentine and forms soluble calcium chelates. A review of the literature and a discussion of the different indications and considerations for its usage are presented. PMID:24966721

  5. The Acid-Base Titration of a Very Weak Acid: Boric Acid

    ERIC Educational Resources Information Center

    Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

    2012-01-01

    A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

  6. Comparison of Buffer Effect of Different Acids During Sandstone Acidizing

    NASA Astrophysics Data System (ADS)

    Umer Shafiq, Mian; Khaled Ben Mahmud, Hisham; Hamid, Mohamed Ali

    2015-04-01

    The most important concern of sandstone matrix acidizing is to increase the formation permeability by removing the silica particles. To accomplish this, the mud acid (HF: HCl) has been utilized successfully for many years to stimulate the sandstone formations, but still it has many complexities. This paper presents the results of laboratory investigations of different acid combinations (HF: HCl, HF: H3PO4 and HF: HCOOH). Hydrofluoric acid and fluoboric acid are used to dissolve clays and feldspar. Phosphoric and formic acids are added as a buffer to maintain the pH of the solution; also it allows the maximum penetration of acid into the core sample. Different tests have been performed on the core samples before and after the acidizing to do the comparative study on the buffer effect of these acids. The analysis consists of permeability, porosity, color change and pH value tests. There is more increase in permeability and porosity while less change in pH when phosphoric and formic acids were used compared to mud acid. From these results it has been found that the buffer effect of phosphoric acid and formic acid is better than hydrochloric acid.

  7. Oxalic acid excretion after intravenous ascorbic acid administration.

    PubMed

    Robitaille, Line; Mamer, Orval A; Miller, Wilson H; Levine, Mark; Assouline, Sarit; Melnychuk, David; Rousseau, Caroline; Hoffer, L John

    2009-02-01

    Ascorbic acid is frequently administered intravenously by alternative health practitioners and, occasionally, by mainstream physicians. Intravenous administration can greatly increase the amount of ascorbic acid that reaches the circulation, potentially increasing the risk of oxalate crystallization in the urinary space. To investigate this possibility, we developed gas chromatography mass spectrometry methodology and sampling and storage procedures for oxalic acid analysis without interference from ascorbic acid and measured urinary oxalic acid excretion in people administered intravenous ascorbic acid in doses ranging from 0.2 to 1.5 g/kg body weight. In vitro oxidation of ascorbic acid to oxalic acid did not occur when urine samples were brought immediately to pH less than 2 and stored at -30 degrees C within 6 hours. Even very high ascorbic acid concentrations did not interfere with the analysis when oxalic acid extraction was carried out at pH 1. As measured during and over the 6 hours after ascorbic acid infusions, urinary oxalic acid excretion increased with increasing doses, reaching approximately 80 mg at a dose of approximately 100 g. We conclude that, when studied using correct procedures for sample handling, storage, and analysis, less than 0.5% of a very large intravenous dose of ascorbic acid is recovered as urinary oxalic acid in people with normal renal function.

  8. [Studies on interaction of acid-treated nanotube titanic acid and amino acids].

    PubMed

    Zhang, Huqin; Chen, Xuemei; Jin, Zhensheng; Liao, Guangxi; Wu, Xiaoming; Du, Jianqiang; Cao, Xiang

    2010-06-01

    Nanotube titanic acid (NTA) has distinct optical and electrical character, and has photocatalysis character. In accordance with these qualities, NTA was treated with acid so as to enhance its surface activity. Surface structures and surface groups of acid-treated NTA were characterized and analyzed by Transmission Electron Microscope (TEM) and Fourier Transform Infrared Spectrometry (FT-IR). The interaction between acid-treated NTA and amino acids was investigated. Analysis results showed that the lengths of acid-treated NTA became obviously shorter. The diameters of nanotube bundles did not change obviously with acid-treating. Meanwhile, the surface of acid-treated NTA was cross-linked with carboxyl or esterfunction. In addition, acid-treated NTA can catch amino acid residues easily, and then form close combination.

  9. Alkyl phosphonic acids and sulfonic acids in the Murchison meteorite

    NASA Technical Reports Server (NTRS)

    Cooper, George W.; Onwo, Wilfred M.; Cronin, John R.

    1992-01-01

    Homologous series of alkyl phosphonic acids and alkyl sulfonic acids, along with inorganic orthophosphate and sulfate, are identified in water extracts of the Murchison meteorite after conversion to their t-butyl dimethylsilyl derivatives. The methyl, ethyl, propyl, and butyl compounds are observed in both series. Five of the eight possible alkyl phosphonic acids and seven of the eight possible alkyl sulfonic acids through C4 are identified. Abundances decrease with increasing carbon number as observed of other homologous series indigenous to Murchison. Concentrations range downward from approximately 380 nmol/gram in the alkyl sulfonic acid series, and from 9 nmol/gram in the alkyl phosphonic acid series.

  10. Effect of domoic acid on brain amino acid levels.

    PubMed

    Durán, R; Arufe, M C; Arias, B; Alfonso, M

    1995-03-01

    The administration of Domoic Acid (Dom) in a 0.2 mg/kg i.p. dose induces changes in the levels of amino acids of neurochemical interest (Asp, Glu, Gly, Tau, Ala, GABA) in different rat brain regions (hypothalamus, hippocampus, amygdala, striatum, cortex and midbrain). The most affected amino acid is the GABA, the main inhibitory amino acid neurotransmitter, whereas glutamate, the main excitatory amino acid, is not affected. The rat brain regions that seem to be the main target of the Dom action belong to the limbic system (hippocampus, amygdala). The possible implication of the amino acids in the actions of Dom is also discussed.

  11. Hydrofluoric acid poisoning

    MedlinePlus

    Chemical Emergencies: Case Definition: Hydrofluoric Acid . Centers for Disease Control and Prevention, U.S. Dept of Health and Human Services; 2005. Goldfrank LR, ed. Goldfrank's Toxicologic Emergencies . 8th ed. New York, NY: McGraw Hill; 2006. Wax PM, Young A. ...

  12. Plant fatty acid hydroxylase

    DOEpatents

    Somerville, Chris; van de Loo, Frank

    2000-01-01

    The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds.

  13. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Oates-Bockenstedt, Catherine

    1997-01-01

    Details an activity designed to motivate students by incorporating science-related issues into a classroom debate. Includes "The Acid Rain Bill" and "Position Guides" for student roles as committee members, consumers, governors, industry owners, tourism professionals, senators, and debate directors. (DKM)

  14. Acid Rain Investigations.

    ERIC Educational Resources Information Center

    Hugo, John C.

    1992-01-01

    Presents an activity in which students investigate the formation of solid ammonium chloride aerosol particles to help students better understand the concept of acid rain. Provides activity objectives, procedures, sample data, clean-up instructions, and questions and answers to help interpret the data. (MDH)

  15. The Acid Rain Game.

    ERIC Educational Resources Information Center

    Rakow, Steven J.; Glenn, Allen

    1982-01-01

    Provides rationale for and description of an acid rain game (designed for two players), a problem-solving model for elementary students. Although complete instructions are provided, including a copy of the game board, the game is also available for Apple II microcomputers. Information for the computer program is available from the author.…

  16. Acid Rain Classroom Projects.

    ERIC Educational Resources Information Center

    Demchik, Michael J.

    2000-01-01

    Describes a curriculum plan in which students learn about acid rain through instructional media, research and class presentations, lab activities, simulations, design, and design implementation. Describes the simulation activity in detail and includes materials, procedures, instructions, examples, results, and discussion sections. (SAH)

  17. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Bybee, Rodger; And Others

    1984-01-01

    Describes an activity which provides opportunities for role-playing as industrialists, ecologists, and government officials. The activity involves forming an international commission on acid rain, taking testimony, and, based on the testimony, making recommendations to governments on specific ways to solve the problem. Includes suggestions for…

  18. Acid rain bibliography

    SciTech Connect

    Sayers, C.S.

    1983-09-01

    This bibliography identifies 900 citations on various aspects of Acid Rain, covering published bibliographies, books, reports, conference and symposium proceedings, audio visual materials, pamphlets and newsletters. It includes five sections: citations index (complete record of author, title, source, order number); KWIC index; title index; author index; and source index. 900 references.

  19. Docosahexaenoic acid and lactation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Docosahexaenoic acid (DHA) is an important component of membrane phospholipids in the retina, and brain, and accumulates rapidly in these tissues during early infancy. DHA is present in human milk, but the amount varies considerably and is largely dependent on maternal diet. This article reviews dat...

  20. Spermatotoxicity of dichloroacetic acid

    EPA Science Inventory

    The testicular toxicity of dichloroacetic acid (DCA), a disinfection byproduct of drinking water, was evaluated in adult male rats given both single and multiple (up to 14 d) oral doses. Delayed spermiation and altered resorption of residual bodies were observed in rats given sin...

  1. Water surface is acidic

    PubMed Central

    Buch, Victoria; Milet, Anne; Vácha, Robert; Jungwirth, Pavel; Devlin, J. Paul

    2007-01-01

    Water autoionization reaction 2H2O → H3O− + OH− is a textbook process of basic importance, resulting in pH = 7 for pure water. However, pH of pure water surface is shown to be significantly lower, the reduction being caused by proton stabilization at the surface. The evidence presented here includes ab initio and classical molecular dynamics simulations of water slabs with solvated H3O+ and OH− ions, density functional studies of (H2O)48H+ clusters, and spectroscopic isotopic-exchange data for D2O substitutional impurities at the surface and in the interior of ice nanocrystals. Because H3O+ does, but OH− does not, display preference for surface sites, the H2O surface is predicted to be acidic with pH < 4.8. For similar reasons, the strength of some weak acids, such as carbonic acid, is expected to increase at the surface. Enhanced surface acidity can have a significant impact on aqueous surface chemistry, e.g., in the atmosphere. PMID:17452650

  2. Acid rain sourcebook

    SciTech Connect

    Elliott, T.C.; Schwieger, R.G.

    1984-01-01

    Discusses the problem of acid rain and how it can be controlled. The book is divided into seven key sections: the problem and the legislative solutions; international mitigation programs; planning the US program; emissions reduction-before combustion; emissions/reduction-during combustion; emissions reduction-after combustion and engineering solutions under development. 13 papers have been abstracted separately.

  3. The acid rain sourcebook

    SciTech Connect

    Elliott, T.C.; Schwieger, R.G.

    1985-01-01

    A reference collection of specialized information discussions on areas critical to the acid rain issue: problem definition, impact of legislation, emissions standards, international perspective, cost scenarios, and engineering solutions. The text is reinforced with 130 illustrations and about 50 tables. Contents: International mitigation programs. Emissions reduction: before combustion; during combustion; after combustion. Engineering solutions under development.

  4. A Direct, Biomass-Based Synthesis of Benzoic Acid: Formic Acid-Mediated Deoxygenation of the Glucose-Derived Materials Quinic Acid and Shikimic Acid

    SciTech Connect

    Arceo, Elena; Ellman, Jonathan; Bergman, Robert

    2010-05-03

    An alternative biomass-based route to benzoic acid from the renewable starting materials quinic acid and shikimic acid is described. Benzoic acid is obtained selectively using a highly efficient, one-step formic acid-mediated deoxygenation method.

  5. Synthesis of acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

    DOEpatents

    Moens, Luc

    2003-06-24

    A process of preparing an acid addition salt of delta-aminolevulinc acid comprising: a) dissolving a lower alkyl 5-bromolevulinate and hexamethylenetetramine in a solvent selected from the group consisting of water, ethyl acetate, chloroform, acetone, ethanol, tetrahydrofuran and acetonitrile, to form a quaternary ammonium salt of the lower alkyl 5-bromolevulinate; and b) hydrolyzing the quaternary ammonium salt with an inorganic acid to form an acid addition salt of delta-aminolevulinic acid.

  6. Photostabilization of ascorbic acid with citric acid, tartaric acid and boric acid in cream formulations.

    PubMed

    Ahmad, I; Ali Sheraz, M; Ahmed, S; Shad, Z; Vaid, F H M

    2012-06-01

    This study involves the evaluation of the effect of certain stabilizers, that is, citric acid (CT), tartaric acid (TA) and boric acid (BA) on the degradation of ascorbic acid (AH(2) ) in oil-in-water cream formulations exposed to the UV light and stored in the dark. The apparent first-order rate constants (0.34-0.95 × 10(-3) min(-1) in light, 0.38-1.24 × 10(-2) day(-1) in dark) for the degradation reactions in the presence of the stabilizers have been determined. These rate constants have been used to derive the second-order rate constants (0.26-1.45 × 10(-2) M(-1) min(-1) in light, 3.75-8.50 × 10(-3) M(-1) day(-1) in dark) for the interaction of AH(2) and the individual stabilizers. These stabilizers are effective in causing the inhibition of the rate of degradation of AH(2) both in the light and in the dark. The inhibitory effect of the stabilizers is in the order of CT > TA > BA. The rate of degradation of AH(2) in the presence of these stabilizers in the light is about 120 times higher than that in the dark. This could be explained on the basis of the deactivation of AH(2) -excited triplet state by CT and TA and by the inhibition of AH(2) degradation through complex formation with BA. AH(2) leads to the formation of dehydroascorbic acid (A) by chemical and photooxidation in cream formulations.

  7. Specific bile acids inhibit hepatic fatty acid uptake

    PubMed Central

    Nie, Biao; Park, Hyo Min; Kazantzis, Melissa; Lin, Min; Henkin, Amy; Ng, Stephanie; Song, Sujin; Chen, Yuli; Tran, Heather; Lai, Robin; Her, Chris; Maher, Jacquelyn J.; Forman, Barry M.; Stahl, Andreas

    2012-01-01

    Bile acids are known to play important roles as detergents in the absorption of hydrophobic nutrients and as signaling molecules in the regulation of metabolism. Here we tested the novel hypothesis that naturally occurring bile acids interfere with protein-mediated hepatic long chain free fatty acid (LCFA) uptake. To this end stable cell lines expressing fatty acid transporters as well as primary hepatocytes from mouse and human livers were incubated with primary and secondary bile acids to determine their effects on LCFA uptake rates. We identified ursodeoxycholic acid (UDCA) and deoxycholic acid (DCA) as the two most potent inhibitors of the liver-specific fatty acid transport protein 5 (FATP5). Both UDCA and DCA were able to inhibit LCFA uptake by primary hepatocytes in a FATP5-dependent manner. Subsequently, mice were treated with these secondary bile acids in vivo to assess their ability to inhibit diet-induced hepatic triglyceride accumulation. Administration of DCA in vivo via injection or as part of a high-fat diet significantly inhibited hepatic fatty acid uptake and reduced liver triglycerides by more than 50%. In summary, the data demonstrate a novel role for specific bile acids, and the secondary bile acid DCA in particular, in the regulation of hepatic LCFA uptake. The results illuminate a previously unappreciated means by which specific bile acids, such as UDCA and DCA, can impact hepatic triglyceride metabolism and may lead to novel approaches to combat obesity-associated fatty liver disease. PMID:22531947

  8. Acid diffusion through polyaniline membranes

    SciTech Connect

    Su, T.M.; Huang, S.C.; Conklin, J.A.

    1995-12-01

    Polyaniline membranes in the undoped (base) and doped (acid) forms are studied for their utility as pervaporation membranes. The separation of water from mixtures of propionic acid, acetic acid and formic acid have been demonstrated from various feed compositions. Doped polyaniline displays an enhanced selectivity of water over these organic acids as compared with undoped polyaniline. For as-cast polyaniline membranes a diffusion coefficient (D) on the order of 10{sup -9} cm{sup 2}/sec has been determined for the flux of protons through the membranes using hydrochloric acid.

  9. Fatty acid-producing hosts

    DOEpatents

    Pfleger, Brian F; Lennen, Rebecca M

    2013-12-31

    Described are hosts for overproducing a fatty acid product such as a fatty acid. The hosts include an exogenous nucleic acid encoding a thioesterase and, optionally, an exogenous nucleic acid encoding an acetyl-CoA carboxylase, wherein an acyl-CoA synthetase in the hosts are functionally delected. The hosts prefereably include the nucleic acid encoding the thioesterase at an intermediate copy number. The hosts are preferably recominantly stable and growth-competent at 37.degree. C. Methods of producing a fatty acid product comprising culturing such hosts at 37.degree. C. are also described.

  10. Radioenzymatic assay for quinolinic acid

    SciTech Connect

    Foster, A.C.; Okuno, E.; Brougher, D.S.; Schwarcz, R.

    1986-10-01

    A new and rapid method for the determination of the excitotoxic tryptophan metabolite quinolinic acid is based on its enzymatic conversion to nicotinic acid mononucleotide and, in a second step utilizing (/sup 3/H)ATP, further to (/sup 3/H) deamido-NAD. Specificity of the assay is assured by using a highly purified preparation of the specific quinolinic acid-catabolizing enzyme, quinolinic acid phosphoribosyltransferase, in the initial step. The limit of sensitivity was found to be 2.5 pmol of quinolinic acid, sufficient to conveniently determine quinolinic acid levels in small volumes of human urine and blood plasma.

  11. Progress in engineering acid stress resistance of lactic acid bacteria.

    PubMed

    Wu, Chongde; Huang, Jun; Zhou, Rongqing

    2014-02-01

    Lactic acid bacteria (LAB) are widely used for the production of a variety of fermented foods, and are considered as probiotic due to their health-promoting effect. However, LAB encounter various environmental stresses both in industrial fermentation and application, among which acid stress is one of the most important survival challenges. Improving the acid stress resistance may contribute to the application and function of probiotic action to the host. Recently, the advent of genomics, functional genomics and high-throughput technologies have allowed for the understanding of acid tolerance mechanisms at a systems level, and many method to improve acid tolerance have been developed. This review describes the current progress in engineering acid stress resistance of LAB. Special emphasis is placed on engineering cellular microenvironment (engineering amino acid metabolism, introduction of exogenous biosynthetic capacity, and overproduction of stress response proteins) and maintaining cell membrane functionality. Moreover, strategies to improve acid tolerance and the related physiological mechanisms are also discussed.

  12. Scorpion peptide LqhIT2 activates phenylpropanoid pathways via jasmonate to increase rice resistance to rice leafrollers.

    PubMed

    Tianpei, Xiuzi; Li, Dong; Qiu, Ping; Luo, Jie; Zhu, Yingguo; Li, Shaoqing

    2015-01-01

    LqhIT2 is an insect-specific toxin peptide identified in Leiurus quinquestriatus hebraeus that can be toxic to lepidoptera pests. However, whether LqhIT2 induces insect resistance in rice, and how the LqhIT2 influences the biochemical metabolism of rice plants remains unknown. Here, purified LqhIT2-GST fusion protein had toxicity to rice leafrollers. Meanwhile, in vitro and field trials showed that LqhIT2 transgenic rice plants were less damaged by rice leafrollers compared to the wild type plants. Introducing LqhIT2 primed the elevated expression of lipoxygenase, a key component of the jasmonic acid biosynthetic pathway, together with enhanced linolenic acid, cis-(+)-12-oxophytodienoic acid, jasmonic acid, and jasmonic acid-isoleucine levels. In addition, phenylalanine ammonia-lyase, a key gene of the phenylpropanoid pathway, was up-regulated. Correspondingly, the contents of downstream products of the phenylpropanoid pathway such as flavonoids and lignins, were also increased in LqhIT2 transgenic plants. These changes were paralleled by decreased starch, glucose, and glucose-6-phosphate accumulation, the key metabolites of glycolysis pathway that supplies the raw material and intermediate carbon products for phenylpropanoids biosyntheses. These findings suggest that, in addition to its own toxicity against pests, LqhIT2 activate the phenylpropanoid pathway via jasmonate-mediated priming, which subsequently increases flavonoid and lignin content and improves insect resistance in rice.

  13. Abscisic acid has a key role in modulating diverse plant-pathogen interactions.

    PubMed

    Fan, Jun; Hill, Lionel; Crooks, Casey; Doerner, Peter; Lamb, Chris

    2009-08-01

    We isolated an activation-tagged Arabidopsis (Arabidopsis thaliana) line, constitutive disease susceptibility2-1D (cds2-1D), that showed enhanced bacterial growth when challenged with various Pseudomonas syringae strains. Systemic acquired resistance and systemic PATHOGENESIS-RELATED GENE1 induction were also compromised in cds2-1D. The T-DNA insertion adjacent to NINE-CIS-EPOXYCAROTENOID DIOXYGENASE5 (NCED5), one of six genes encoding the abscisic acid (ABA) biosynthetic enzyme NCED, caused a massive increase in transcript level and enhanced ABA levels >2-fold. Overexpression of NCED genes recreated the enhanced disease susceptibility phenotype. NCED2, NCED3, and NCED5 were induced, and ABA accumulated strongly following compatible P. syringae infection. The ABA biosynthetic mutant aba3-1 showed reduced susceptibility to virulent P. syringae, and ABA, whether through exogenous application or endogenous accumulation in response to mild water stress, resulted in increased bacterial growth following challenge with virulent P. syringae, indicating that ABA suppresses resistance to P. syringae. Likewise ABA accumulation also compromised resistance to the biotrophic oomycete Hyaloperonospora arabidopsis, whereas resistance to the fungus Alternaria brassicicola was enhanced in cds2-1D plants and compromised in aba3-1 plants, indicating that ABA promotes resistance to this necrotroph. Comparison of the accumulation of salicylic acid and jasmonic acid in the wild type, cds2-1D, and aba3-1 plants challenged with P. syringae showed that ABA promotes jasmonic acid accumulation and exhibits a complex antagonistic relationship with salicylic acid. Our findings provide genetic evidence that the abiotic stress signal ABA also has profound roles in modulating diverse plant-pathogen interactions mediated at least in part by cross talk with the jasmonic acid and salicylic acid biotic stress signal pathways.

  14. Effect of phenolic acids on glucose and organic acid metabolism by lactic acid bacteria from wine.

    PubMed

    Campos, Francisco M; Figueiredo, Ana R; Hogg, Tim A; Couto, José A

    2009-06-01

    The influence of phenolic (p-coumaric, caffeic, ferulic, gallic and protocatechuic) acids on glucose and organic acid metabolism by two strains of wine lactic acid bacteria (Oenococcus oeni VF and Lactobacillus hilgardii 5) was investigated. Cultures were grown in modified MRS medium supplemented with different phenolic acids. Cellular growth was monitored and metabolite concentrations were determined by HPLC-RI. Despite the strong inhibitory effect of most tested phenolic acids on the growth of O. oeni VF, the malolactic activity of this strain was not considerably affected by these compounds. While less affected in its growth, the capacity of L. hilgardii 5 to degrade malic acid was clearly diminished. Except for gallic acid, the addition of phenolic acids delayed the metabolism of glucose and citric acid in both strains tested. It was also found that the presence of hydroxycinnamic acids (p-coumaric, caffeic and ferulic) increased the yield of lactic and acetic acid production from glucose by O. oeni VF and not by L. hilgardii 5. The results show that important oenological characteristics of wine lactic acid bacteria, such as the malolactic activity and the production of volatile organic acids, may be differently affected by the presence of phenolic acids, depending on the bacterial species or strain.

  15. NAPAP (National Acid Precipitation Assessment Program) results on acid rain

    SciTech Connect

    Not Available

    1990-06-01

    The National Acid Precipitation Assessment Program (NAPAP) was mandated by Congress in 1980 to study the effects of acid rain. The results of 10 years of research on the effect of acid deposition and ozone on forests, particularly high elevation spruce and fir, southern pines, eastern hardwoods and western conifers, will be published this year.

  16. Acid Earth--The Global Threat of Acid Pollution.

    ERIC Educational Resources Information Center

    McCormick, John

    Acid pollution is a major international problem, but the debate it has elicited has often clouded the distinction between myth and facts. This publication attempts to concerning the acid pollution situation. This publication attempts to identify available facts. It is the first global review of the problem of acid pollution and the first to…

  17. Boric/sulfuric acid anodize - Alternative to chromic acid anodize

    NASA Astrophysics Data System (ADS)

    Koop, Rodney; Moji, Yukimori

    1992-04-01

    The suitability of boric acid/sulfuric acid anodizing (BSAA) solution as a more environmentally acceptable replacement of the chromic acid anodizing (CAA) solution was investigated. Results include data on the BSAA process optimization, the corrosion protection performance, and the compatibility with aircraft finishing. It is shown that the BSSA implementation as a substitude for CAA was successful.

  18. Circulating folic acid in plasma: relation to folic acid fortification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The implementation of folic acid fortification in the United States has resulted in unprecedented amounts of this synthetic form of folate in the American diet. Folic acid in circulation may be a useful measure of physiologic exposure to synthetic folic acid, and there is a potential for elevated co...

  19. College Chemistry Students' Mental Models of Acids and Acid Strength

    ERIC Educational Resources Information Center

    McClary, LaKeisha; Talanquer, Vicente

    2011-01-01

    The central goal of this study was to characterize the mental models of acids and acid strength expressed by advanced college chemistry students when engaged in prediction, explanation, and justification tasks that asked them to rank chemical compounds based on their relative acid strength. For that purpose we completed a qualitative research…

  20. Eucomic acid methanol monosolvate

    PubMed Central

    Li, Guo-Qiang; Li, Yao-Lan; Wang, Guo-Cai; Liang, Zhi-Hong; Jiang, Ren-Wang

    2011-01-01

    In the crystal structure of the title compound [systematic name: 2-hy­droxy-2-(4-hy­droxy­benz­yl)butane­dioic acid methanol monosolvate], C11H12O6·CH3OH, the dihedral angles between the planes of the carboxyl groups and the benzene ring are 51.23 (9) and 87.97 (9)°. Inter­molecular O—H⋯O hydrogen-bonding inter­actions involving the hy­droxy and carb­oxy­lic acid groups and the methanol solvent mol­ecule give a three-dimensional structure. PMID:22091200

  1. Autohydrolysis of phytic acid.

    PubMed

    Hull, S R; Gray, J S; Montgomery, R

    1999-09-10

    The autohydrolysis of phytic acid at 120 degrees C resulted in the formation of most of the phosphate esters of myo-inositol in varying amounts depending upon the reaction time. Eighteen of the 39 chromatographically distinct myo-inositol mono-, bis-, tris-, tetrakis-, pentakis-, and hexakisphosphates have been characterized using two different HPLC systems. These myo-inositol phosphates were partially purified by preparative anion-exchange chromatography under acidic and alkaline elution conditions. The combination of these two methods provides a two-tiered chromatographic approach to the rapid and sensitive identification of inositol phosphates in complex mixtures. Identification of the products was confirmed by 1D and 2D (1)H NMR analysis. The analytical procedure was applied to the autohydrolysis of the mixture of inositol phosphates from corn steep water.

  2. Optimize acid gas removal

    SciTech Connect

    Nicholas, D.M.; Wilkins, J.T.

    1983-09-01

    Innovative design of physical solvent plants for acid gas removal can materially reduce both installation and operating costs. A review of the design considerations for one physical solvent process (Selexol) points to numerous arrangements for potential improvement. These are evaluated for a specific case in four combinations that identify an optimum for the case in question but, more importantly, illustrate the mechanism for use for such optimization elsewhere.

  3. Perfluorooctanoic acid and environmental risks

    EPA Science Inventory

    Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acids (PFAA) family of chemicals, which consist of a carbon backbone typically four to fourteen carbons in length and a charged functional moiety.

  4. Ideas about Acids and Alkalis.

    ERIC Educational Resources Information Center

    Toplis, Rob

    1998-01-01

    Investigates students' ideas, conceptions, and misconceptions about acids and alkalis before and after a teaching sequence in a small-scale research project. Concludes that student understanding of acids and alkalis is lacking. (DDR)

  5. Pantothenic acid (Vitamin B5)

    MedlinePlus

    Pantothenic acid is a vitamin, also known as vitamin B5. It is widely found in both plants and animals ... Vitamin B5 is commercially available as D-pantothenic acid, as well as dexpanthenol and calcium pantothenate, which ...

  6. Folic Acid Questions and Answers

    MedlinePlus

    ... Controls NCBDDD Cancel Submit Search The CDC Folic Acid Note: Javascript is disabled or is not supported ... please visit this page: About CDC.gov . Folic Acid Homepage Facts Quiz Frequently Asked Questions General Information ...

  7. Omega-3 fatty acids (image)

    MedlinePlus

    Omega-3 fatty acids are a form of polyunsaturated fat that the body derives from food. Omega-3s (and omega-6s) are known as essential fatty acids (EFAs) because they are important for good health. ...

  8. Immunomodulatory spherical nucleic acids.

    PubMed

    Radovic-Moreno, Aleksandar F; Chernyak, Natalia; Mader, Christopher C; Nallagatla, Subbarao; Kang, Richard S; Hao, Liangliang; Walker, David A; Halo, Tiffany L; Merkel, Timothy J; Rische, Clayton H; Anantatmula, Sagar; Burkhart, Merideth; Mirkin, Chad A; Gryaznov, Sergei M

    2015-03-31

    Immunomodulatory nucleic acids have extraordinary promise for treating disease, yet clinical progress has been limited by a lack of tools to safely increase activity in patients. Immunomodulatory nucleic acids act by agonizing or antagonizing endosomal toll-like receptors (TLR3, TLR7/8, and TLR9), proteins involved in innate immune signaling. Immunomodulatory spherical nucleic acids (SNAs) that stimulate (immunostimulatory, IS-SNA) or regulate (immunoregulatory, IR-SNA) immunity by engaging TLRs have been designed, synthesized, and characterized. Compared with free oligonucleotides, IS-SNAs exhibit up to 80-fold increases in potency, 700-fold higher antibody titers, 400-fold higher cellular responses to a model antigen, and improved treatment of mice with lymphomas. IR-SNAs exhibit up to eightfold increases in potency and 30% greater reduction in fibrosis score in mice with nonalcoholic steatohepatitis (NASH). Given the clinical potential of SNAs due to their potency, defined chemical nature, and good tolerability, SNAs are attractive new modalities for developing immunotherapies.

  9. Immunomodulatory spherical nucleic acids

    PubMed Central

    Radovic-Moreno, Aleksandar F.; Chernyak, Natalia; Mader, Christopher C.; Nallagatla, Subbarao; Kang, Richard S.; Hao, Liangliang; Walker, David A.; Halo, Tiffany L.; Merkel, Timothy J.; Rische, Clayton H.; Anantatmula, Sagar; Burkhart, Merideth; Mirkin, Chad A.; Gryaznov, Sergei M.

    2015-01-01

    Immunomodulatory nucleic acids have extraordinary promise for treating disease, yet clinical progress has been limited by a lack of tools to safely increase activity in patients. Immunomodulatory nucleic acids act by agonizing or antagonizing endosomal toll-like receptors (TLR3, TLR7/8, and TLR9), proteins involved in innate immune signaling. Immunomodulatory spherical nucleic acids (SNAs) that stimulate (immunostimulatory, IS-SNA) or regulate (immunoregulatory, IR-SNA) immunity by engaging TLRs have been designed, synthesized, and characterized. Compared with free oligonucleotides, IS-SNAs exhibit up to 80-fold increases in potency, 700-fold higher antibody titers, 400-fold higher cellular responses to a model antigen, and improved treatment of mice with lymphomas. IR-SNAs exhibit up to eightfold increases in potency and 30% greater reduction in fibrosis score in mice with nonalcoholic steatohepatitis (NASH). Given the clinical potential of SNAs due to their potency, defined chemical nature, and good tolerability, SNAs are attractive new modalities for developing immunotherapies. PMID:25775582

  10. Microbial naphthenic Acid degradation.

    PubMed

    Whitby, Corinne

    2010-01-01

    Naphthenic acids (NAs) are an important group of trace organic pollutants predominantly comprising saturated aliphatic and alicyclic carboxylic acids. NAs are ubiquitous; occurring naturally in hydrocarbon deposits (petroleum, oil sands, bitumen, and crude oils) and also have widespread industrial uses. Consequently, NAs can enter the environment from both natural and anthropogenic processes. NAs are highly toxic, recalcitrant compounds that persist in the environment for many years, and it is important to develop efficient bioremediation strategies to decrease both their abundance and toxicity in the environment. However, the diversity of microbial communities involved in NA-degradation, and the mechanisms by which NAs are biodegraded, are poorly understood. This lack of knowledge is mainly due to the difficulties in identifying and purifying individual carboxylic acid compounds from complex NA mixtures found in the environment, for microbial biodegradation studies. This paper will present an overview of NAs, their origin and fate in the environment, and their toxicity to the biota. The review describes the microbial degradation of both naturally occurring and chemically synthesized NAs. Proposed pathways for aerobic NA biodegradation, factors affecting NA biodegradation rates, and possible bioremediation strategies are also discussed.

  11. Amino acids in carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Lawless, J. G.; Peterson, E.

    1975-01-01

    Studies with the combined gas chromatograph-mass spectrometer were conducted to characterize further the amino acids found in extracts of the Murchison meteorite. With the exception of beta-aminoisobutyric acid, all of the amino acids which were found in previous studies of the Murchison meteorite and the Murray meteorite have been identified. The results obtained lend further support to the hypothesis that amino acids are present in the Murchison meteorite as the result of an extraterrestrial abiotic synthesis.

  12. Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

    PubMed

    Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

    2002-12-06

    Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

  13. Carboxylic acid sorption regeneration process

    DOEpatents

    King, C. Judson; Poole, Loree J.

    1995-01-01

    Carboxylic acids are sorbed from aqueous feedstocks into an organic liquid phase or onto a solid adsorbent. The acids are freed from the sorbent phase by treating it with aqueous alkylamine thus forming an alkylammonium carboxylate which is dewatered and decomposed to the desired carboxylic acid and the alkylamine.

  14. An Umbrella for Acid Rain.

    ERIC Educational Resources Information Center

    Randal, Judith

    1979-01-01

    The Environmental Protection Agency has awarded several grants to study effects of and possible solutions to the problem of "acid rain"; pollution from atmospheric nitric and sulfuric acids. The research program is administered through North Carolina State University at Raleigh and will focus on biological effects of acid rain. (JMF)

  15. Carboxylic acid sorption regeneration process

    DOEpatents

    King, C.J.; Poole, L.J.

    1995-05-02

    Carboxylic acids are sorbed from aqueous feedstocks into an organic liquid phase or onto a solid adsorbent. The acids are freed from the sorbent phase by treating it with aqueous alkylamine thus forming an alkylammonium carboxylate which is dewatered and decomposed to the desired carboxylic acid and the alkylamine. 10 figs.

  16. Scientists Puzzle Over Acid Rain

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Reports on a growing concern over increased acidity in atmospheric percipitation. Explores possible causes of the increased acidity, identifies chemical components of precipitation in various parts of the world, and presents environmental changes that might be attributed to the acidity. (GS)

  17. [Total synthesis of nordihydroguaiaretic acid].

    PubMed

    Wu, A X; Zhao, Y R; Chen, N; Pan, X F

    1997-04-01

    beta-Keto ester(5) was obtained from vanilin through etherification, oxidation and condensation with acetoacetic ester, (5) on oxidative coupling reaction by NaOEt/I2 produced dimer (6) in high yield. Acid catalyzed cyclodehydration of (6) gave the furan derivative(7), and by a series of selective hydrogenation nordihydroguaiaretic acid, furoguaiacin dimethyl ether and dihydroguaiaretic acid dimethyl ether were synthesized.

  18. Pantothenic acid biosynthesis in zymomonas

    SciTech Connect

    Tao, Luan; Tomb, Jean-Francois; Viitanen, Paul V.

    2014-07-01

    Zymomonas is unable to synthesize pantothenic acid and requires this essential vitamin in growth medium. Zymomonas strains transformed with an operon for expression of 2-dehydropantoate reductase and aspartate 1-decarboxylase were able to grow in medium lacking pantothenic acid. These strains may be used for ethanol production without pantothenic acid supplementation in seed culture and fermentation media.

  19. Microbial degradation of poly(amino acid)s.

    PubMed

    Obst, Martin; Steinbüchel, Alexander

    2004-01-01

    Natural poly(amino acid)s are a group of poly(ionic) molecules (ionomers) with various biological functions and putative technical applications and play, therefore, an important role both in nature and in human life. Because of their biocompatibility and their synthesis from renewable resources, poly(amino acid)s may be employed for many different purposes covering a broad spectrum of medical, pharmaceutical, and personal care applications as well as the domains of agriculture and of environmental applications. Biodegradability is one important advantage of naturally occurring poly(amino acid)s over many synthetic polymers. The intention of this review is to give an overview about the enzyme systems catalyzing the initial steps in poly(amino acid) degradation. The focus is on the naturally occurring poly(amino acid)s cyanophycin, poly(epsilon-L-lysine) and poly(gamma-glutamic acid); but biodegradation of structurally related synthetic polyamides such as poly(aspartic acid) and nylons, which are known from various technical applications, is also included.

  20. Jasmonates trigger prey-induced formation of 'outer stomach' in carnivorous sundew plants.

    PubMed

    Nakamura, Yoko; Reichelt, Michael; Mayer, Veronika E; Mithöfer, Axel

    2013-05-22

    It has been widely accepted that the growth-related phytohormone auxin is the endogenous signal that initiates bending movements of plant organs. In 1875, Charles Darwin described how the bending movement of leaves in carnivorous sundew species formed an 'outer stomach' that allowed the plants to enclose and digest captured insect prey. About 100 years later, auxin was suggested to be the factor responsible for this movement. We report that prey capture induces both leaf bending and the accumulation of defence-related jasmonate phytohormones. In Drosera capensis fed with fruitflies, within 3 h after prey capture and simultaneous with leaf movement, we detected an increase in jasmonic acid and its isoleucine conjugate. This accumulation was spatially restricted to the bending segment of the leaves. The application of jasmonates alone was sufficient to trigger leaf bending. Only living fruitflies or the body fluids of crushed fruitflies induced leaf curvature; neither dead flies nor mechanical treatment had any effect. Our findings strongly suggest that the formation of the 'outer stomach' in Drosera is a chemonastic movement that is triggered by accumulation of endogenous jasmonates. These results suggest that in carnivorous sundew plants the jasmonate cascade might have been adapted to facilitate carnivory rather than to defend against herbivores.

  1. Jasmonates trigger prey-induced formation of ‘outer stomach’ in carnivorous sundew plants

    PubMed Central

    Nakamura, Yoko; Reichelt, Michael; Mayer, Veronika E.; Mithöfer, Axel

    2013-01-01

    It has been widely accepted that the growth-related phytohormone auxin is the endogenous signal that initiates bending movements of plant organs. In 1875, Charles Darwin described how the bending movement of leaves in carnivorous sundew species formed an ‘outer stomach’ that allowed the plants to enclose and digest captured insect prey. About 100 years later, auxin was suggested to be the factor responsible for this movement. We report that prey capture induces both leaf bending and the accumulation of defence-related jasmonate phytohormones. In Drosera capensis fed with fruitflies, within 3 h after prey capture and simultaneous with leaf movement, we detected an increase in jasmonic acid and its isoleucine conjugate. This accumulation was spatially restricted to the bending segment of the leaves. The application of jasmonates alone was sufficient to trigger leaf bending. Only living fruitflies or the body fluids of crushed fruitflies induced leaf curvature; neither dead flies nor mechanical treatment had any effect. Our findings strongly suggest that the formation of the ‘outer stomach’ in Drosera is a chemonastic movement that is triggered by accumulation of endogenous jasmonates. These results suggest that in carnivorous sundew plants the jasmonate cascade might have been adapted to facilitate carnivory rather than to defend against herbivores. PMID:23516244

  2. Composition for nucleic acid sequencing

    DOEpatents

    Korlach, Jonas; Webb, Watt W.; Levene, Michael; Turner, Stephen; Craighead, Harold G.; Foquet, Mathieu

    2008-08-26

    The present invention is directed to a method of sequencing a target nucleic acid molecule having a plurality of bases. In its principle, the temporal order of base additions during the polymerization reaction is measured on a molecule of nucleic acid, i.e. the activity of a nucleic acid polymerizing enzyme on the template nucleic acid molecule to be sequenced is followed in real time. The sequence is deduced by identifying which base is being incorporated into the growing complementary strand of the target nucleic acid by the catalytic activity of the nucleic acid polymerizing enzyme at each step in the sequence of base additions. A polymerase on the target nucleic acid molecule complex is provided in a position suitable to move along the target nucleic acid molecule and extend the oligonucleotide primer at an active site. A plurality of labelled types of nucleotide analogs are provided proximate to the active site, with each distinguishable type of nucleotide analog being complementary to a different nucleotide in the target nucleic acid sequence. The growing nucleic acid strand is extended by using the polymerase to add a nucleotide analog to the nucleic acid strand at the active site, where the nucleotide analog being added is complementary to the nucleotide of the target nucleic acid at the active site. The nucleotide analog added to the oligonucleotide primer as a result of the polymerizing step is identified. The steps of providing labelled nucleotide analogs, polymerizing the growing nucleic acid strand, and identifying the added nucleotide analog are repeated so that the nucleic acid strand is further extended and the sequence of the target nucleic acid is determined.

  3. Evolution of rosmarinic acid biosynthesis.

    PubMed

    Petersen, Maike; Abdullah, Yana; Benner, Johannes; Eberle, David; Gehlen, Katja; Hücherig, Stephanie; Janiak, Verena; Kim, Kyung Hee; Sander, Marion; Weitzel, Corinna; Wolters, Stefan

    2009-01-01

    Rosmarinic acid and chlorogenic acid are caffeic acid esters widely found in the plant kingdom and presumably accumulated as defense compounds. In a survey, more than 240 plant species have been screened for the presence of rosmarinic and chlorogenic acids. Several rosmarinic acid-containing species have been detected. The rosmarinic acid accumulation in species of the Marantaceae has not been known before. Rosmarinic acid is found in hornworts, in the fern family Blechnaceae and in species of several orders of mono- and dicotyledonous angiosperms. The biosyntheses of caffeoylshikimate, chlorogenic acid and rosmarinic acid use 4-coumaroyl-CoA from the general phenylpropanoid pathway as hydroxycinnamoyl donor. The hydroxycinnamoyl acceptor substrate comes from the shikimate pathway: shikimic acid, quinic acid and hydroxyphenyllactic acid derived from l-tyrosine. Similar steps are involved in the biosyntheses of rosmarinic, chlorogenic and caffeoylshikimic acids: the transfer of the 4-coumaroyl moiety to an acceptor molecule by a hydroxycinnamoyltransferase from the BAHD acyltransferase family and the meta-hydroxylation of the 4-coumaroyl moiety in the ester by a cytochrome P450 monooxygenase from the CYP98A family. The hydroxycinnamoyltransferases as well as the meta-hydroxylases show high sequence similarities and thus seem to be closely related. The hydroxycinnamoyltransferase and CYP98A14 from Coleus blumei (Lamiaceae) are nevertheless specific for substrates involved in RA biosynthesis showing an evolutionary diversification in phenolic ester metabolism. Our current view is that only a few enzymes had to be "invented" for rosmarinic acid biosynthesis probably on the basis of genes needed for the formation of chlorogenic and caffeoylshikimic acid while further biosynthetic steps might have been recruited from phenylpropanoid metabolism, tocopherol/plastoquinone biosynthesis and photorespiration.

  4. The politics of acid rain

    SciTech Connect

    Wilcher, M.E. )

    1989-01-01

    This work examines and compares the acid rain policies through the different political systems of Canada, Great Britain and the United States. Because the flow of acid rain can transcend national boundaries, acid rain has become a crucial international problem. According to the author, because of differences in governmental institutions and structure, the extent of governmental intervention in the industrial economy, the degree of reliance on coal for power generation, and the extent of acid rain damage, national responses to the acid rain problem have varied.

  5. [Stewart's acid-base approach].

    PubMed

    Funk, Georg-Christian

    2007-01-01

    In addition to paCO(2), Stewart's acid base model takes into account the influence of albumin, inorganic phosphate, electrolytes and lactate on acid-base equilibrium. It allows a comprehensive and quantitative analysis of acid-base disorders. Particularly simultaneous and mixed metabolic acid-base disorders, which are common in critically ill patients, can be assessed. Stewart's approach is therefore a valuable tool in addition to the customary acid-base approach based on bicarbonate or base excess. However, some chemical aspects of Stewart's approach remain controversial.

  6. Tested Demonstrations: Color Oscillations in the Formic Acid-Nitric Acid-Sulfuric Acid System.

    ERIC Educational Resources Information Center

    Raw, C. J. G.; And Others

    1983-01-01

    Presented are procedures for demonstrating the production of color oscillations when nitric acid is added to a formic acid/concentrated sulfuric acid mixture. Because of safety considerations, "Super-8" home movie of the color changes was found to be satisfactory for demonstration purposes. (JN)

  7. Amino acids in Arctic aerosols

    NASA Astrophysics Data System (ADS)

    Scalabrin, E.; Zangrando, R.; Barbaro, E.; Kehrwald, N. M.; Gabrieli, J.; Barbante, C.; Gambaro, A.

    2012-11-01

    Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids and quantify compounds at fmol m-3 levels. Mean total FAA concentration was 1070 fmol m-3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45-60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m-3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (< 0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanic emissions.

  8. Amino acids in Arctic aerosols

    NASA Astrophysics Data System (ADS)

    Scalabrin, E.; Zangrando, R.; Barbaro, E.; Kehrwald, N. M.; Gabrieli, J.; Barbante, C.; Gambaro, A.

    2012-07-01

    Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids to quantify compounds at fmol m-3 levels. Mean total FAA concentration was 1070 fmol m-3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45-60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m-3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (<0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanics.

  9. Twinning of dodecanedicarboxylic acid

    NASA Technical Reports Server (NTRS)

    Sen, R.; Wilcox, W. R.

    1986-01-01

    Twinning of 1,10-dodecanedicarboxyl acid (DDA) was observed in 0.1 mm thick films with a polarizing microscope. Twins originated from polycrystalline regions which tended to nucleate on twin faces, and terminated by intersection gone another. Twinning increased dramatically with addition of organic compounds with a similar molecular size and shape. Increasing the freezing rate, increasing the temperature gradient, and addition of silica particles increased twinning. It is proposed that twins nucleate with polycrystals and sometimes anneal out before they become observable. The impurities may enhance twinning either by lowering the twin energy or by adsorbing on growing faces.

  10. Synthesis of amino acids

    DOEpatents

    Davis, J.W. Jr.

    1979-09-21

    A method is described for synthesizing amino acids preceding through novel intermediates of the formulas: R/sub 1/R/sub 2/C(OSOC1)CN, R/sub 1/R/sub 2/C(C1)CN and (R/sub 1/R/sub 2/C(CN)O)/sub 2/SO wherein R/sub 1/ and R/sub 2/ are each selected from hydrogen and monovalent hydrocarbon radicals of 1 to 10 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art.

  11. New highly toxic bile acids derived from deoxycholic acid, chenodeoxycholic acid and lithocholic acid.

    PubMed

    Májer, Ferenc; Sharma, Ruchika; Mullins, Claire; Keogh, Luke; Phipps, Sinead; Duggan, Shane; Kelleher, Dermot; Keely, Stephen; Long, Aideen; Radics, Gábor; Wang, Jun; Gilmer, John F

    2014-01-01

    We have prepared a new panel of 23 BA derivatives of DCA, chenodeoxycholic acid (CDCA) and lithocholic acid (LCA) in order to study the effect of dual substitution with 3-azido and 24-amidation, features individually associated with cytotoxicity in our previous work. The effect of the compounds on cell viability of HT-1080 and Caco-2 was studied using the 3-[4,5-dimethylthizol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Compounds with high potency towards reduction of cell viability were further studied using flow cytometry in order to understand the mechanism of cell death. Several compounds were identified with low micromolar IC₅₀ values for reducing cell viability in the Caco-2 and HT1080 cell lines, making them among the most potent BA apoptotic agents reported to date. There was no evidence of relationship between overall hydrophobicity and cytotoxicity supporting the idea that cell death induction by BAs may be structure-specific. Compounds derived from DCA caused cell death through apoptosis. There was some evidence of selectivity between the two cell lines studied which may be due to differing expression of CD95/FAS. The more toxic compounds increased ROS production in Caco-2 cells, and co-incubation with the antioxidant N-acetyl cysteine blunted pro-apoptotic effects. The properties these compounds suggest that there may be specific mechanism(s) mediating BA induced cell death. Compound 8 could be useful for investigating this phenomenon.

  12. Cryoprotection from lipoteichoic acid

    NASA Astrophysics Data System (ADS)

    Rice, Charles V.; Middaugh, Amy; Wickham, Jason R.; Friedline, Anthony; Thomas, Kieth J.; Johnson, Karen; Zachariah, Malcolm; Garimella, Ravindranth

    2012-10-01

    Numerous chemical additives lower the freezing point of water, but life at sub-zero temperatures is sustained by a limited number of biological cryoprotectants. Antifreeze proteins in fish, plants, and insects provide protection to a few degrees below freezing. Microbes have been found to survive at even lower temperatures, and with a few exceptions, antifreeze proteins are missing. Survival has been attributed to external factors, such as the high salt concentration of brine veins and adhesion to particulates or ice crystal defects. We have discovered an endogenous cryoprotectant in the cell wall of bacteria, lipoteichoic acid biopolymers. Adding 1% LTA to bacteria cultures immediately prior to freezing provides 50% survival rate, similar to the results obtained with 1% glycerol. In the absence of an additive, bacterial survival is negligible as measured with the resazurin cell viability assay. The mode of action for LTA cryoprotection is unknown. With a molecular weight of 3-5 kDa, it is unlikely to enter the cell cytoplasm. Our observations suggest that teichoic acids could provide a shell of liquid water around biofilms and planktonic bacteria, removing the need for brine veins to prevent bacterial freezing.

  13. Nucleic Acid Detection Methods

    DOEpatents

    Smith, Cassandra L.; Yaar, Ron; Szafranski, Przemyslaw; Cantor, Charles R.

    1998-05-19

    The invention relates to methods for rapidly determining the sequence and/or length a target sequence. The target sequence may be a series of known or unknown repeat sequences which are hybridized to an array of probes. The hybridized array is digested with a single-strand nuclease and free 3'-hydroxyl groups extended with a nucleic acid polymerase. Nuclease cleaved heteroduplexes can be easily distinguish from nuclease uncleaved heteroduplexes by differential labeling. Probes and target can be differentially labeled with detectable labels. Matched target can be detected by cleaving resulting loops from the hybridized target and creating free 3-hydroxyl groups. These groups are recognized and extended by polymerases added into the reaction system which also adds or releases one label into solution. Analysis of the resulting products using either solid phase or solution. These methods can be used to detect characteristic nucleic acid sequences, to determine target sequence and to screen for genetic defects and disorders. Assays can be conducted on solid surfaces allowing for multiple reactions to be conducted in parallel and, if desired, automated.

  14. Nucleic acid detection methods

    DOEpatents

    Smith, C.L.; Yaar, R.; Szafranski, P.; Cantor, C.R.

    1998-05-19

    The invention relates to methods for rapidly determining the sequence and/or length a target sequence. The target sequence may be a series of known or unknown repeat sequences which are hybridized to an array of probes. The hybridized array is digested with a single-strand nuclease and free 3{prime}-hydroxyl groups extended with a nucleic acid polymerase. Nuclease cleaved heteroduplexes can be easily distinguish from nuclease uncleaved heteroduplexes by differential labeling. Probes and target can be differentially labeled with detectable labels. Matched target can be detected by cleaving resulting loops from the hybridized target and creating free 3-hydroxyl groups. These groups are recognized and extended by polymerases added into the reaction system which also adds or releases one label into solution. Analysis of the resulting products using either solid phase or solution. These methods can be used to detect characteristic nucleic acid sequences, to determine target sequence and to screen for genetic defects and disorders. Assays can be conducted on solid surfaces allowing for multiple reactions to be conducted in parallel and, if desired, automated. 18 figs.

  15. Ribonucleic acid purification.

    PubMed

    Martins, R; Queiroz, J A; Sousa, F

    2014-08-15

    Research on RNA has led to many important biological discoveries and improvement of therapeutic technologies. From basic to applied research, many procedures employ pure and intact RNA molecules; however their isolation and purification are critical steps because of the easy degradability of RNA, which can impair chemical stability and biological functionality. The current techniques to isolate and purify RNA molecules still have several limitations and the requirement for new methods able to improve RNA quality to meet regulatory demands is growing. In fact, as basic research improves the understanding of biological roles of RNAs, the biopharmaceutical industry starts to focus on them as a biotherapeutic tools. Chromatographic bioseparation is a high selective unit operation and is the major option in the purification of biological compounds, requiring high purity degree. In addition, its application in biopharmaceutical manufacturing is well established. This paper discusses the importance and the progress of RNA isolation and purification, considering RNA applicability both in research and clinical fields. In particular and in view of the high specificity, affinity chromatography has been recently applied to RNA purification processes. Accordingly, recent chromatographic investigations based on biorecognition phenomena occurring between RNA and amino acids are focused. Histidine and arginine have been used as amino acid ligands, and their ability to isolate different RNA species demonstrated a multipurpose applicability in molecular biology analysis and RNA therapeutics preparation, highlighting the potential contribution of these methods to overcome the challenges of RNA purification.

  16. Growth of nitric acid hydrates on thin sulfuric acid films

    NASA Technical Reports Server (NTRS)

    Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.

    1994-01-01

    Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1-3 x 10(exp -4) Torr H2O and 1-2.5 x 10(exp -6) Torr HNO3) and subjected to cooling and heating cycles. Fourier Transform Infrared (FTIR) spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.

  17. CELL PENETRATION BY ACIDS : VI. THE CHLOROACETIC ACIDS.

    PubMed

    Crozier, W J

    1922-09-20

    Measurements of the penetration of tissue from Chromodoris zebra are believed to show that a determining factor in penetration involves the establishment of a critical pH (near 3.5) in relation to superficial cell proteins. The rapidity with which this state is produced depends upon acid strength, and upon some property of the acid influencing the speed of absorption; hence it is necessary to compare acids within groups of chemical relationship. The actual speed of penetration observed with any acid is dependent upon two influences: preliminary chemical combination with the outer protoplasm, followed by diffusion. The variation of the temperature coefficient of penetration velocity with the concentration of acid, and the effect of size (age) of individual providing the tissue sample agree in demonstrating the significant part played by diffusion. In comparing different acids, however, their mode of chemical union with the protoplasm determines the general order of penetrating ability.

  18. Methyl Jasmonate Reduces Water Stress in Strawberry.

    PubMed

    Wang

    1999-11-01

    The effect of methyl jasmonate (MJ) on changes of oxygen-scavenging enzyme activities and membrane lipid composition was studied in strawberry leaves under water stress. Under water stress, MJ treatment reduced the increase of peroxidase (EC 1.11.1.7; POD) activity, maintained higher catalase (EC 1.11.1.6; CAT) and superoxide dismutase (EC 1.15.1.1; SOD) activities, and ascorbic acid content. In addition, MJ treatment reduced transpiration and membrane-lipid peroxidation as expressed by malondialdehyde (MDA) content, lessened the reduction of membrane lipids, glycolipids [monogalactosyl diglyceride (MGDG), digalactosyl diglyceride (DGDG)], and phospholipids [phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and phosphatidylinositol (PI)]. In water-deficit conditions, MJ treatment also alleviated the decline in the degree of fatty acid unsaturation and the ratio of linolenic (18:3) to linoleic acid (18:2). These results indicate that MJ treatment appears to alter the metabolism of strawberry plants rendering the tissue better able to withstand water stress.

  19. Bile acids: regulation of synthesis.

    PubMed

    Chiang, John Y L

    2009-10-01

    Bile acids are physiological detergents that generate bile flow and facilitate intestinal absorption and transport of lipids, nutrients, and vitamins. Bile acids also are signaling molecules and inflammatory agents that rapidly activate nuclear receptors and cell signaling pathways that regulate lipid, glucose, and energy metabolism. The enterohepatic circulation of bile acids exerts important physiological functions not only in feedback inhibition of bile acid synthesis but also in control of whole-body lipid homeostasis. In the liver, bile acids activate a nuclear receptor, farnesoid X receptor (FXR), that induces an atypical nuclear receptor small heterodimer partner, which subsequently inhibits nuclear receptors, liver-related homolog-1, and hepatocyte nuclear factor 4alpha and results in inhibiting transcription of the critical regulatory gene in bile acid synthesis, cholesterol 7alpha-hydroxylase (CYP7A1). In the intestine, FXR induces an intestinal hormone, fibroblast growth factor 15 (FGF15; or FGF19 in human), which activates hepatic FGF receptor 4 (FGFR4) signaling to inhibit bile acid synthesis. However, the mechanism by which FXR/FGF19/FGFR4 signaling inhibits CYP7A1 remains unknown. Bile acids are able to induce FGF19 in human hepatocytes, and the FGF19 autocrine pathway may exist in the human livers. Bile acids and bile acid receptors are therapeutic targets for development of drugs for treatment of cholestatic liver diseases, fatty liver diseases, diabetes, obesity, and metabolic syndrome.

  20. Therapeutic targeting of bile acids

    PubMed Central

    Gores, Gregory J.

    2015-01-01

    The first objectives of this article are to review the structure, chemistry, and physiology of bile acids and the types of bile acid malabsorption observed in clinical practice. The second major theme addresses the classical or known properties of bile acids, such as the role of bile acid sequestration in the treatment of hyperlipidemia; the use of ursodeoxycholic acid in therapeutics, from traditional oriental medicine to being, until recently, the drug of choice in cholestatic liver diseases; and the potential for normalizing diverse bowel dysfunctions in irritable bowel syndrome, either by sequestering intraluminal bile acids for diarrhea or by delivering more bile acids to the colon to relieve constipation. The final objective addresses novel concepts and therapeutic opportunities such as the interaction of bile acids and the microbiome to control colonic infections, as in Clostridium difficile-associated colitis, and bile acid targeting of the farnesoid X receptor and G protein-coupled bile acid receptor 1 with consequent effects on energy expenditure, fat metabolism, and glycemic control. PMID:26138466

  1. [Analysis of citric acid and citrates. Citric acid and urolithiasis].

    PubMed

    Leskovar, P

    1979-08-01

    In the first part the physico-chemical, analytic chemical and physiologic biochemical properties of the citric acid are discussed. In the second part the author enters the role of the citric acid in the formation of uric calculi. In the third part is reported on the individual methods of the determination of citric acid and the method practised in the author's laboratory is described.

  2. Rotational study of the bimolecule acetic acid-fluoroacetic acid

    NASA Astrophysics Data System (ADS)

    Feng, Gang; Gou, Qian; Evangelisti, Luca; Caminati, Walther

    2017-01-01

    The rotational spectrum of the acetic acid-fluoroacetic acid bimolecule was measured by using a pulsed jet Fourier transform microwave spectrometer. One conformer, in which fluoroacetic acid is in trans form, has been observed. The rotational transitions are split into two component lines, due to the internal rotation of the methyl group of acetic acid. From these splittings, the corresponding V3 barrier has been determined. The dissociation energy of this complex has been estimated to 66 kJ/mol. An increase of the distance between the two monomers upon the OH → OD substitution (Ubbelohde effect) has been observed.

  3. Esterification by the Plasma Acidic Water: Novel Application of Plasma Acid

    NASA Astrophysics Data System (ADS)

    Gu, Ling

    2014-03-01

    This work explores the possibility of plasma acid as acid catalyst in organic reactions. Plasma acidic water was prepared by dielectric barrier discharge and used to catalyze esterification of n-heptanioc acid with ethanol. It is found that the plasma acidic water has a stable and better performance than sulfuric acid, meaning that it is an excellent acid catalyst. The plasma acidic water would be a promising alternative for classic mineral acid as a more environment friendly acid.

  4. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  5. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  6. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  7. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  8. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  9. [Women's knowledge of folic acid].

    PubMed

    Salgues, Mathilde; Damase-Michel, Christine; Montastruc, Jean-Louis; Lacroix, Isabelle

    2016-10-27

    Many trials have shown that folic acid supplementation before and during pregnancy reduces the risk of neural tube defects in general population. We investigated the knowledge of folic acid in women of child-bearing age. Women of child-bearing age were interviewed by 20 pharmacists living in Haute-Garonne between January and February 2014. One hundred ninety-six women were included in the present study. Out of them, 36% of women never heard of folic acid and 82% were not aware of its benefits. Knowledge was higher in older women, women in a couple and women with higher educational level (P<10(-2)). This study underlines that women are not enough aware of benefits of folic acid during pregnancy. Moreover, previous studies have shown that French women have low use of folic acid during peri-conceptional period. Information of general population will be required for a better prevention of folic acid-preventable NTDs.

  10. Flecainide acetate acetic acid solvates.

    PubMed

    Veldre, Kaspars; Actiņs, Andris; Eglite, Zane

    2011-02-01

    Flecainide acetate forms acetic acid solvates with 0.5 and 2 acetic acid molecules. Powder X-ray diffraction, differential thermal analysis/thermogravimetric, infrared, and potentiometric titration were used to determine the composition of solvates. Flecainide acetate hemisolvate with acetic acid decomposes to form a new crystalline form of flecainide acetate. This form is less stable than the already known polymorphic form at all temperatures, and it is formed due to kinetic reasons. Both flecainide acetate nonsolvated and flecainide acetate hemisolvate forms crystallize in monoclinic crystals, but flecainide triacetate forms triclinic crystals. Solvate formation was not observed when flecainide base was treated with formic acid, propanoic acid, and butanoic acid. Only nonsolvated flecainide salts were obtained in these experiments.

  11. A Simpler Nucleic Acid

    NASA Technical Reports Server (NTRS)

    Orgel, Leslie

    2000-01-01

    It has been supposed that for a nucleic acid analog to pair with RNA it must, like RNA, have a backbone with at least a sixatom repeat; a shorter backbone presumably would not stretch far enough to bind RNA properly. The Eschenmoser group has shown, however, that this first impression is incorrect.As they report in their new paper, Eschenmoser and co-workers ( I ) have now synthesized a substantial number of these polymers, which are called (L)-a-threofuranosyl oligonucleotides or TNAs. They are composed of bases linked to a threose sugar-phosphate backbone, with phosphodiester bonds connecting the nucleotides. The investigators discovered that pairs of complementary TNAs do indeed form stable Watson-Crick double helices and, perhaps more importantly, that TNAs form stable double helices with complementary RNAs and DNAs.

  12. Acid mine drainage

    USGS Publications Warehouse

    Bigham, Jerry M.; Cravotta, Charles A.

    2016-01-01

    Acid mine drainage (AMD) consists of metal-laden solutions produced by the oxidative dissolution of iron sulfide minerals exposed to air, moisture, and acidophilic microbes during the mining of coal and metal deposits. The pH of AMD is usually in the range of 2–6, but mine-impacted waters at circumneutral pH (5–8) are also common. Mine drainage usually contains elevated concentrations of sulfate, iron, aluminum, and other potentially toxic metals leached from rock that hydrolyze and coprecipitate to form rust-colored encrustations or sediments. When AMD is discharged into surface waters or groundwaters, degradation of water quality, injury to aquatic life, and corrosion or encrustation of engineered structures can occur for substantial distances. Prevention and remediation strategies should consider the biogeochemical complexity of the system, the longevity of AMD pollution, the predictive power of geochemical modeling, and the full range of available field technologies for problem mitigation.

  13. Production of polymalic acid and malic acid by Aureobasidium pullulans fermentation and acid hydrolysis.

    PubMed

    Zou, Xiang; Zhou, Yipin; Yang, Shang-Tian

    2013-08-01

    Malic acid is a dicarboxylic acid widely used in the food industry and also a potential C4 platform chemical that can be produced from biomass. However, microbial fermentation for direct malic acid production is limited by low product yield, titer, and productivity due to end-product inhibition. In this work, a novel process for malic acid production from polymalic acid (PMA) fermentation followed by acid hydrolysis was developed. First, a PMA-producing Aureobasidium pullulans strain ZX-10 was screened and isolated. This microbe produced PMA as the major fermentation product at a high-titer equivalent to 87.6 g/L of malic acid and high-productivity of 0.61 g/L h in free-cell fermentation in a stirred-tank bioreactor. Fed-batch fermentations with cells immobilized in a fibrous-bed bioreactor (FBB) achieved the highest product titer of 144.2 g/L and productivity of 0.74 g/L h. The fermentation produced PMA was purified by adsorption with IRA-900 anion-exchange resins, achieving a ∼100% purity and a high recovery rate of 84%. Pure malic acid was then produced from PMA by hydrolysis with 2 M sulfuric acid at 85°C, which followed the first-order reaction kinetics. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application.

  14. Acidic gas capture by diamines

    DOEpatents

    Rochelle, Gary; Hilliard, Marcus

    2011-05-10

    Compositions and methods related to the removal of acidic gas. In particular, the present disclosure relates to a composition and method for the removal of acidic gas from a gas mixture using a solvent comprising a diamine (e.g., piperazine) and carbon dioxide. One example of a method may involve a method for removing acidic gas comprising contacting a gas mixture having an acidic gas with a solvent, wherein the solvent comprises piperazine in an amount of from about 4 to about 20 moles/kg of water, and carbon dioxide in an amount of from about 0.3 to about 0.9 moles per mole of piperazine.

  15. Dipotassium maleate with boric acid.

    PubMed

    Tombul, Mustafa; Guven, Kutalmis; Büyükgüngör, Orhan; Aktas, Huseyin; Durlu, Tahsin Nuri

    2007-09-01

    In the title compound, poly[(mu3-boric acid)-mu4-maleato-dipotassium], [K2(C(4)H(2)O(4)){B(OH)3}]n, there are two independent K+ cations, one bonded to seven O atoms (three from boric acid and four from maleate), and the other eight-coordinate via three boric acid and four maleate O atoms and a weak eta(1)-type coordination to the C=C bond of the maleate central C atoms. Hydrogen bonding links the boric acid ligands and maleate dianions, completing the packing structure.

  16. Organic Acid Production by Basidiomycetes

    PubMed Central

    Takao, Shoichi

    1965-01-01

    Sixty-seven strains belonging to 47 species of Basidiomycetes were examined for their acid-producing abilities in glucose media, in both the presence and absence of CaCO3, in stationary and shake cultures. Some strains were found to produce large quantities of oxalic acid. The oxalic acid-producing strains could be separated into two groups. Strains of one group (mostly brown-rot fungi) were able to produce oxalic acid, regardless of whether CaCO3 was present in the medium. Strains of the other group (mostly white-rot fungi) were characterized by their ability to produce oxalic acid only when CaCO3 was added to the medium. With the latter group, shake-culturing was generally more effective than stationary culturing in respect to acid production. In the CaCO3-containing media, Schizophyllum commune, Merulius tremellosus, and Porodisculus pendulus were found to produce substantial amounts of L-malic acid as a main metabolic product, along with small quantities of oxalic and other acids in shake cultures. Especially, S. commune and M. tremellosus may be employed as malic acid-producing species. PMID:5867653

  17. Preparation and characterization Al3+-bentonite Turen Malang for esterification fatty acid (palmitic acid, oleic acid and linoleic acid)

    NASA Astrophysics Data System (ADS)

    Abdulloh, Abdulloh; Aminah, Nanik Siti; Triyono, Mudasir, Trisunaryanti, Wega

    2016-03-01

    Catalyst preparation and characterization of Al3+-bentonite for esterification of palmitic acid, oleic acid and linoleic acid has been done. Al3+-bentonite catalyst was prepared from natural bentonite of Turen Malang through cation exchange reaction using AlCl3 solution. The catalysts obtained were characterized by XRD, XRF, pyridine-FTIR and surface area analyser using the BET method. Catalyst activity test of Al3+-bentonite for esterification reaction was done at 65°C using molar ratio of metanol-fatty acid of 30:1 and 0.25 g of Al3+-bentonite catalyst for the period of ½, 1, 2, 3, 4 and 5 hours. Based on the characterization results, the Al3+-bentonite Turen Malang catalyst has a d-spacing of 15.63 Ǻ, acid sites of Brönsted and Lewis respectively of 230.79 µmol/g and 99.39 µmol/g, surface area of 507.3 m2/g and the average of radius pore of 20.09 Å. GC-MS analysis results of the oil phase after esterification reaction showed the formation of biodiesel (FAME: Fatty acid methyl ester), namely methyl palmitate, methyl oleate and methyl linoleate. The number of conversions resulted in esterification reaction using Al3+-bentonite Turen Malang catalyst was 74.61%, 37.75%, and 20, 93% for the esterification of palmitic acid, oleic acid and linoleic acid respectively.

  18. DL-beta-aminobutyric acid-induced resistance of potato against Phytophthora infestans requires salicylic acid but not oxylipins.

    PubMed

    Eschen-Lippold, Lennart; Altmann, Simone; Rosahl, Sabine

    2010-05-01

    Inducing systemic resistance responses in crop plants is a promising alternative way of disease management. To understand the underlying signaling events leading to induced resistance, functional analyses of plants defective in defined signaling pathway steps are required. We used potato, one of the economically most-important crop plants worldwide, to examine systemic resistance against the devastating late blight pathogen Phytophthora infestans, induced by treatment with dl-beta-aminobutyric acid (BABA). Transgenic plants impaired in either the 9-lipoxygenase pathway, which produces defense-related compounds, or the 13-lipoxygenase pathway, which generates jasmonic acid-derived signals, expressed wild-type levels of BABA-induced resistance. Plants incapable of accumulating salicylic acid (SA), on the other hand, failed to mount this type of induced resistance. Consistently, treatment of these plants with the SA analog 2,6-dichloroisonicotinic acid restored BABA-induced resistance. Together, these results demonstrate the indispensability of a functional SA pathway for systemic resistance in potato induced by BABA.

  19. Fatty acid-amino acid conjugates diversification in Lepidopteran caterpillars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatty acid amino acid conjugates (FACs) have been found in Noctuid as well as Sphingid caterpillar oral secretions and especially volicitin [N-(17-hydroxylinolenoyl)-L-Glutamine] and its biochemical precursor, N-linolenoyl-L-glutamine, are known elicitors of induced volatile emissions in corn plants...

  20. Sulfuric acid as autocatalyst in the formation of sulfuric acid.

    PubMed

    Torrent-Sucarrat, Miquel; Francisco, Joseph S; Anglada, Josep M

    2012-12-26

    Sulfuric acid can act as a catalyst of its own formation. We have carried out a computational investigation on the gas-phase formation of H(2)SO(4) by hydrolysis of SO(3) involving one and two water molecules, and also in the presence of sulfuric acid and its complexes with one and two water molecules. The hydrolysis of SO(3) requires the concurrence of two water molecules, one of them acting as a catalyzer, and our results predict an important catalytic effect, ranging between 3 and 11 kcal·mol(-1) when the catalytic water molecule is substituted by a sulfuric acid molecule or one of its hydrates. In these cases, the reaction products are either bare sulfuric acid dimer or sulfuric acid dimer complexed with a water molecule. There are broad implications from these new findings. The results of the present investigation show that the catalytic effect of sulfuric acid in the SO(3) hydrolysis can be important in the Earth's stratosphere, in the heterogeneous formation of sulfuric acid and in the formation of aerosols, in H(2)SO(4) formation by aircraft engines, and also in understanding the formation of sulfuric acid in the atmosphere of Venus.

  1. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances

    PubMed Central

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-01

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism. PMID:26742061

  2. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances.

    PubMed

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-04

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism.

  3. Acid rain on acid soil: a new perspective

    SciTech Connect

    Krug, E.C.; Frink, C.R.

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and Northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  4. Acid rain on acid soil: a new perspective

    SciTech Connect

    Krug, E.C.; Frink, C.R.

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  5. Microbial desulfonation of substituted naphthalenesulfonic acids and benzenesulfonic acids.

    PubMed Central

    Zürrer, D; Cook, A M; Leisinger, T

    1987-01-01

    Sulfur-limited batch enrichment cultures containing one of nine multisubstituted naphthalenesulfonates and an inoculum from sewage yielded several taxa of bacteria which could quantitatively utilize 19 sulfonated aromatic compounds as the sole sulfur source for growth. Growth yields were about 4 kg of protein per mol of sulfur. Specific degradation rates were about 4 to 14 mu kat/kg of protein. A Pseudomonas sp., an Arthrobacter sp., and an unidentified bacterium were examined. Each desulfonated at least 16 aromatic compounds, none of which served as a carbon source. Pseudomonas sp. strain S-313 converted 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 5-amino-1-naphthalenesulfonic acid, benzenesulfonic acid, and 3-aminobenzenesulfonic acid to 1-naphthol, 2-naphthol, 5-amino-1-naphthol, phenol, and 3-aminophenol, respectively. Experiments with 18O2 showed that the hydroxyl group was derived from molecular oxygen. PMID:3662502

  6. A comparison of chromic acid and sulfuric acid anodizing

    NASA Technical Reports Server (NTRS)

    Danford, M. D.

    1992-01-01

    Because of federal and state mandates restricting the use of hexavalent chromium, it was deemed worthwhile to compare the corrosion protection afforded 2219-T87 aluminum alloy by both Type I chromic acid and Type II sulfuric acid anodizing per MIL-A-8625. Corrosion measurements were made on large, flat 2219-T87 aluminum alloy sheet material with an area of 1 cm(exp 2) exposed to a corrosive medium of 3.5-percent sodium chloride at pH 5.5. Both ac electrochemical impedance spectroscopy and the dc polarization resistance techniques were employed. The results clearly indicate that the corrosion protection obtained by Type II sulfuric acid anodizing is superior, and no problems should result by substituting Type II sulfuric acid anodizing for Type I chromic acid anodizing.

  7. Carbonic Acid Pretreatment of Biomass

    SciTech Connect

    G. Peter van Walsum; Kemantha Jayawardhana; Damon Yourchisin; Robert McWilliams; Vanessa Castleberry

    2003-05-31

    This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. 1) Solidify the theoretical understanding of the binary CO2/H2O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. 2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. 3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. 4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. 5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for the use of carbonic

  8. Carbonic Acid Retreatment of Biomass

    SciTech Connect

    Baylor university

    2003-06-01

    This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. (1) Solidify the theoretical understanding of the binary CO{sub 2}/H{sub 2}O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. (2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. (3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. (4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. (5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for

  9. Fatty acids and lymphocyte functions.

    PubMed

    Calder, P C; Yaqoob, P; Thies, F; Wallace, F A; Miles, E A

    2002-01-01

    The immune system acts to protect the host against pathogenic invaders. However, components of the immune system can become dysregulated such that their activities are directed against host tissues, so causing damage. Lymphocytes are involved in both the beneficial and detrimental effects of the immune system. Both the level of fat and the types of fatty acid present in the diet can affect lymphocyte functions. The fatty acid composition of lymphocytes, and other immune cells, is altered according to the fatty acid composition of the diet and this alters the capacity of those cells to produce eicosanoids, such as prostaglandin E2, which are involved in immunoregulation. A high fat diet can impair lymphocyte function. Cell culture and animal feeding studies indicate that oleic, linoleic, conjugated linoleic, gamma-linolenic, dihomo-gamma-linolenic, arachidonic, alpha-linolenic, eicosapentaenoic and docosahexaenoic acids can all influence lymphocyte proliferation, the production of cytokines by lymphocytes, and natural killer cell activity. High intakes of some of these fatty acids are necessary to induce these effects. Among these fatty acids the long chain n-3 fatty acids, especially eicosapentaenoic acid, appear to be the most potent when included in the human diet. Although not all studies agree, it appears that fish oil, which contains eicosapentaenoic acid, down regulates the T-helper 1-type response which is associated with chronic inflammatory disease. There is evidence for beneficial effects of fish oil in such diseases; this evidence is strongest for rheumatoid arthritis. Since n-3 fatty acids also antagonise the production of inflammatory eicosanoid mediators from arachidonic acid, there is potential for benefit in asthma and related diseases. Recent evidence indicates that fish oil may be of benefit in some asthmatics but not others.

  10. Infrared spectra of hydrogen-bonded salicylic acid and its derivatives : Salicylic acid and acetylsalicylic acid

    NASA Astrophysics Data System (ADS)

    Wójcik, Marek J.

    1981-11-01

    Infrared spectra of hydrogen-bonded salicylic acid, O-deutero-salicylic acid and acetylsalicylic acid crystals have been studied experimentally and theoretically. Interpretation of these spectra was based on the Witkowski-Maréchal model. Semi-quantitative agreement between experimental and theoretical spectra can be achieved with the simplest form of this model, with values of interaction parameters transferable for equivalent intermolecular hydrogen bonds.

  11. Anacardic Acid, Salicylic Acid, and Oleic Acid Differentially Alter Cellular Bioenergetic Function in Breast Cancer Cells.

    PubMed

    Radde, Brandie N; Alizadeh-Rad, Negin; Price, Stephanie M; Schultz, David J; Klinge, Carolyn M

    2016-11-01

    Anacardic acid is a dietary and medicinal phytochemical that inhibits breast cancer cell proliferation and uncouples oxidative phosphorylation (OXPHOS) in isolated rat liver mitochondria. Since mitochondrial-targeted anticancer therapy (mitocans) may be useful in breast cancer, we examined the effect of anacardic acid on cellular bioenergetics and OXPHOS pathway proteins in breast cancer cells modeling progression to endocrine-independence: MCF-7 estrogen receptor α (ERα)+ endocrine-sensitive; LCC9 and LY2 ERα+, endocrine-resistant, and MDA-MB-231 triple negative breast cancer (TNBC) cells. At concentrations similar to cell proliferation IC50 s, anacardic acid reduced ATP-linked oxygen consumption rate (OCR), mitochondrial reserve capacity, and coupling efficiency while increasing proton leak, reflecting mitochondrial toxicity which was greater in MCF-7 compared to endocrine-resistant and TNBC cells. These results suggest tolerance in endocrine-resistant and TNBC cells to mitochondrial stress induced by anacardic acid. Since anacardic acid is an alkylated 2-hydroxybenzoic acid, the effects of salicylic acid (SA, 2-hydroxybenzoic acid moiety) and oleic acid (OA, monounsaturated alkyl moiety) were tested. SA inhibited whereas OA stimulated cell viability. In contrast to stimulation of basal OCR by anacardic acid (uncoupling effect), neither SA nor OA altered basal OCR- except OA inhibited basal and ATP-linked OCR, and increased ECAR, in MDA-MB-231 cells. Changes in OXPHOS proteins correlated with changes in OCR. Overall, neither the 2-hydroxybenzoic acid moiety nor the monounsaturated alky moiety of anacardic acid is solely responsible for the observed mitochondria-targeted anticancer activity in breast cancer cells and hence both moieties are required in the same molecule for the observed effects. J. Cell. Biochem. 117: 2521-2532, 2016. © 2016 Wiley Periodicals, Inc.

  12. Production of Succinic Acid from Citric Acid and Related Acids by Lactobacillus Strains

    PubMed Central

    Kaneuchi, Choji; Seki, Masako; Komagata, Kazuo

    1988-01-01

    A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, α-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli. PMID:16347795

  13. Synthesis of new kojic acid based unnatural α-amino acid derivatives.

    PubMed

    Balakrishna, C; Payili, Nagaraju; Yennam, Satyanarayana; Devi, P Uma; Behera, Manoranjan

    2015-11-01

    An efficient method for the preparation of kojic acid based α-amino acid derivatives by alkylation of glycinate schiff base with bromokojic acids have been described. Using this method, mono as well as di alkylated kojic acid-amino acid conjugates have been prepared. This is the first synthesis of C-linked kojic acid-amino acid conjugate where kojic acid is directly linked to amino acid through a C-C bond.

  14. Getting Back to Basics (& Acidics)

    ERIC Educational Resources Information Center

    Rhodes, Sam

    2006-01-01

    This article describes a few novel acid-base experiments intended to introduce students to the basic concepts of acid-base chemistry and provide practical examples that apply directly to the study of biology and the human body. Important concepts such as the reaction between carbon dioxide and water, buffers and protein denaturation, are covered.…

  15. Synthesis of pyromellitic acid esters

    NASA Technical Reports Server (NTRS)

    Fedorova, V. A.; Donchak, V. A.; Martynyuk-Lototskaya, A. N.

    1985-01-01

    The ester acids necessary for studyng the thermochemical properties of pyromellitic acid (PMK)-based peroxides were investigated. Obtaining a tetramethyl ester of a PMK was described. The mechanism of an esterification reaction is discussed, as is the complete esterification of PMK with primary alcohol.

  16. Acid Rain: What's the Forecast?

    ERIC Educational Resources Information Center

    Bybee, Rodger

    1984-01-01

    Discusses various types of acid rain, considered to be a century-old problem. Topics include: wet and dry deposition, effects on a variety of environments, ecosystems subject to detrimental effects, and possible solutions to the problem. A list of recommended resources on acid rain is provided. (BC)

  17. Acid Rain: An Educational Opportunity?

    ERIC Educational Resources Information Center

    Marion, James I.

    1984-01-01

    Deals with how educators can handle the subject of acid rain; illustrates suggestions with experiences of grade nine students visiting Frost Valley Environmental Education Center (Oliverea, New York) to learn scientific concepts through observation of outdoor phenomena, including a stream; and discusses acid rain, pH levels, and pollution control…

  18. Acid Precipitation: Causes and Consequences.

    ERIC Educational Resources Information Center

    Babich, Harvey; And Others

    1980-01-01

    This article is the first of three articles in a series on the acid rain problem in recent years. Discussed are the causes of acid precipitation and its consequences for the abiotic and biotic components of the terrestrial and aquatic ecosystems, and for man-made materials. (Author/SA)

  19. Acid rain & electric utilities II

    SciTech Connect

    1997-12-31

    This document presents reports which were presented at the Acid Rain and Electric Utilities Conference. Topics include environmental issues and electric utilities; acid rain program overview; global climate change and carbon dioxide; emissions data management; compliance; emissions control; allowance and trading; nitrogen oxides; and assessment. Individual reports have been processed separately for the United States Department of Energy databases.

  20. Acid Rain: The Scientific Challenge.

    ERIC Educational Resources Information Center

    Godfrey, Paul J.

    1991-01-01

    Documents the workings and findings of the Massachusetts Acid Rain Monitoring Project, which has pooled the volunteer efforts of more than 1,000 amateur and professional scientists since 1983. Reports on the origins of air pollution, the prediction of acid rain, and its effects on both water life and land resources. (JJK)

  1. Beneficial effects of hyaluronic acid.

    PubMed

    Sudha, Prasad N; Rose, Maximas H

    2014-01-01

    Biomaterials are playing a vital role in our day-to-day life. Hyaluronan (hyaluronic acid), a biomaterial, receives special attention among them. Hyaluronic acid (HA) is a polyanionic natural polymer occurring as linear polysaccharide composed of glucuronic acid and N-acetylglucosamine repeats via a β-1,4 linkage. It is the most versatile macromolecule present in the connective tissues of all vertebrates. Hyaluronic acid has a wide range of applications with its excellent physicochemical properties such as biodegradability, biocompatibility, nontoxicity, and nonimmunogenicity and serves as an excellent tool in biomedical applications such as osteoarthritis surgery, ocular surgery, plastic surgery, tissue engineering, and drug delivery. It plays a key role in cushioning and lubricating the body and is abundant in the eyes, joints, and heart valves. A powerful antioxidant, hyaluronic acid is perhaps best known for its ability to bond water to tissue. Hyaluronan production increases in proliferating cells, and the polymer may play a role in mitosis. This chapter gives an overview of hyaluronic acid and its physicochemical properties and applications. This chapter gives a deep understanding on the special benefits of hyaluronic acid in the fields of pharmaceutical, medical, and environmental applications. Hyaluronic acid paves the way for beneficial research and applications to the welfare of life forms.

  2. Phosphorus derivatives of salicylic acid

    NASA Astrophysics Data System (ADS)

    Chvertkina, L. V.; Khoklov, P. S.; Mironov, Vladimir F.

    1992-10-01

    The present state of work on the methods of synthesis, chemical properties, and practical applications of phosphorus-containing derivatives of salicylic acid has been reviewed. The characteristics of the chemical transformations of cyclic and acyclic phosphorus derivatives of salicylic acid related to the coordination state of the phosphorus atom have been examined. The bibliography includes 158 references.

  3. Protein and amino acid nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy cow protein and amino acid nutrition have a significant role in sustainable dairying. Protein, amino acids, and nitrogen are inextricably linked through effects in the rumen, metabolism of the cow, and environmental nutrient management. Feeding systems have been making progress toward emphasiz...

  4. Acid Tests and Basic Fun.

    ERIC Educational Resources Information Center

    McBride, John W.

    1995-01-01

    Explores acids and bases using different indicators, such as turmeric, purple grape juice, and lichens. Because some of these indicators are not as sensitive as cabbage juice or litmus paper, determining to which acids and bases each indicator is sensitive presents an enjoyable, problem-solving challenge for students. Presents directions for…

  5. Attenuation of the jasmonate burst, plant defensive traits, and resistance to specialist monarch caterpillars on shaded common milkweed (Asclepias syriaca).

    PubMed

    Agrawal, Anurag A; Kearney, Emily E; Hastings, Amy P; Ramsey, Trey E

    2012-07-01

    Plant responses to herbivory and light competition are often in opposing directions, posing a potential conflict for plants experiencing both stresses. For sun-adapted species, growing in shade typically makes plants more constitutively susceptible to herbivores via reduced structural and chemical resistance traits. Nonetheless, the impact of light environment on induced resistance has been less well-studied, especially in field experiments that link physiological mechanisms to ecological outcomes. Accordingly, we studied induced resistance of common milkweed (Asclepias syriaca, a sun-adapted plant), and linked hormonal responses, resistance traits, and performance of specialist monarch caterpillars (Danaus plexippus) in varying light environments. In natural populations, plants growing under forest-edge shade showed reduced levels of resistance traits (lower leaf toughness, cardenolides, and trichomes) and enhanced light-capture traits (higher specific leaf area, larger leaves, and lower carbon-to-nitrogen ratio) compared to paired plants in full sun. In a field experiment repeated over two years, only milkweeds growing in full sun exhibited induced resistance to monarchs, whereas plants growing in shade were constitutively more susceptible and did not induce resistance. In a more controlled field experiment, plant hormones were higher in the sun (jasmonic acid, salicylic acid, abscisic acid, indole acidic acid) and were induced by herbivory (jasmonic acid and abscisic acid). In particular, the jasmonate burst following herbivory was halved in plants raised in shaded habitats, and this correspondingly reduced latex induction (but not cardenolide induction). Thus, we provide a mechanistic basis for the attenuation of induced plant resistance in low resource environments. Additionally, there appears to be specificity in these interactions, with light-mediated impacts on jasmonate-induction being stronger for latex exudation than cardenolides.

  6. Acid Ceramidase in Melanoma

    PubMed Central

    Realini, Natalia; Palese, Francesca; Pizzirani, Daniela; Pontis, Silvia; Basit, Abdul; Bach, Anders; Ganesan, Anand; Piomelli, Daniele

    2016-01-01

    Acid ceramidase (AC) is a lysosomal cysteine amidase that controls sphingolipid signaling by lowering the levels of ceramides and concomitantly increasing those of sphingosine and its bioactive metabolite, sphingosine 1-phosphate. In the present study, we evaluated the role of AC-regulated sphingolipid signaling in melanoma. We found that AC expression is markedly elevated in normal human melanocytes and proliferative melanoma cell lines, compared with other skin cells (keratinocytes and fibroblasts) and non-melanoma cancer cells. High AC expression was also observed in biopsies from human subjects with Stage II melanoma. Immunofluorescence studies revealed that the subcellular localization of AC differs between melanocytes (where it is found in both cytosol and nucleus) and melanoma cells (where it is primarily localized to cytosol). In addition to having high AC levels, melanoma cells generate lower amounts of ceramides than normal melanocytes do. This down-regulation in ceramide production appears to result from suppression of the de novo biosynthesis pathway. To test whether AC might contribute to melanoma cell proliferation, we blocked AC activity using a new potent (IC50 = 12 nm) and stable inhibitor. AC inhibition increased cellular ceramide levels, decreased sphingosine 1-phosphate levels, and acted synergistically with several, albeit not all, antitumoral agents. The results suggest that AC-controlled sphingolipid metabolism may play an important role in the control of melanoma proliferation. PMID:26553872

  7. Lead-acid battery

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1983-01-01

    A light weight lead-acid battery (30) having a positive terminal (36) and a negative terminal (34) and including one or more cells or grid stacks having a plurality of vertically stacked conductive monoplates (10, 20) with positive active material and negative active material deposited on alternating plates in the cell or grid stack. Electrolyte layers (26, 28) positioned between each monoplate are included to provide a battery cell having four sides which is capable of being electrically charged and discharged. Two vertical positive bus bars (42, 43) are provided on opposite sides of the battery cell for connecting the monoplates (10) with positive active material together in parallel current conducting relation. In addition, two negative bus bars (38, 39) on opposite sides of the battery cell each being adjacent the positive bus bars are provided for connecting the monoplates (20) with negative active material together in parallel current conducting relation. The positive (42, 43) and negative (38, 39) bus bars not only provide a low resistance method for connecting the plurality of conductive monoplates of their respective battery terminals (36, 34) but also provides support and structural strength to the battery cell structure. In addition, horizontal orientation of monoplates (10, 20) is provided in a vertical stacking arrangement to reduce electrolyte stratification and short circuiting due to flaking of positive and negative active materials from the monoplates.

  8. Fumaric acid production by fermentation

    PubMed Central

    Roa Engel, Carol A.; Zijlmans, Tiemen W.; van Gulik, Walter M.; van der Wielen, Luuk A. M.

    2008-01-01

    The potential of fumaric acid as a raw material in the polymer industry and the increment of cost of petroleum-based fumaric acid raises interest in fermentation processes for production of this compound from renewable resources. Although the chemical process yields 112% w/w fumaric acid from maleic anhydride and the fermentation process yields only 85% w/w from glucose, the latter raw material is three times cheaper. Besides, the fermentation fixes CO2. Production of fumaric acid by Rhizopus species and the involved metabolic pathways are reviewed. Submerged fermentation systems coupled with product recovery techniques seem to have achieved economically attractive yields and productivities. Future prospects for improvement of fumaric acid production include metabolic engineering approaches to achieve low pH fermentations. PMID:18214471

  9. Atmospheric dust and acid rain

    SciTech Connect

    Hedin, L.O.; Likens, G.E.

    1996-12-01

    Why is acid rain still an environmental problem in Europe and North America despite antipollution reforms? The answer really is blowing in the wind: atmospheric dust. These airborne particles can help neutralize the acids falling on forests, but dust levels are unusually low these days. In the air dust particles can neutralize acid rain. What can we do about acid rain and atmospheric dust? Suggestions range from the improbable to the feasible. One reasonable suggestion is to reduce emissions of acidic pollutants to levels that can be buffered by natural quantities of basic compounds in the atmosphere; such a goal would mean continued reductions in sulfur dioxide and nitrogen oxides, perhaps even greater than those prescribed in the 1990 Amendments to the Clean Air Act in the U.S. 5 figs.

  10. SIALIC ACIDS AND AUTOIMMUNE DISEASE

    PubMed Central

    Mahajan, Vinay S.; Pillai, Shiv

    2016-01-01

    summary An important underlying mechanism that contributes to autoimmunity is the loss of inhibitory signaling in the immune system. Sialic acid-recognizing Ig superfamily lectins or Siglecs are a family of cell surface proteins largely expressed in hematopoietic cells. The majority of Siglecs are inhibitory receptors expressed in immune cells that bind to sialic acid containing ligands and recruit SH2-domain containing tyrosine phosphatases to their cytoplasmic tails. They deliver inhibitory signals that can contribute to the constraining of immune cells and thus protect the host from autoimmunity. The inhibitory functions of CD22/Siglec-2 and Siglec-G and their contributions to tolerance and autoimmunity, primarily in the B lymphocyte context, are considered in some detail in this review. The relevance to autoimmunity and unregulated inflammation of modified sialic acids, enzymes that modify sialic acid, and other sialic acid binding proteins are also reviewed. PMID:26683151

  11. Regulation of epinasty induced by 2,4-dichlorophenoxyacetic acid in pea and Arabidopsis plants.

    PubMed

    Pazmiño, D M; Rodríguez-Serrano, M; Sanz, M; Romero-Puertas, M C; Sandalio, L M

    2014-07-01

    The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) causes uncontrolled cell division and malformed growth in plants, giving rise to leaf epinasty and stem curvature. In this study, mechanisms involved in the regulation of leaf epinasty induced by 2,4-D were studied using different chemicals involved in reactive oxygen species (ROS) accumulation (diphenyleniodonium, butylated hydroxyanisole, EDTA, allopurinol), calcium channels (LaCl3), protein phosphorylation (cantharidin, wortmannin) and ethylene emission/perception (aminoethoxyvinyl glycine, AgNO3). The effect of these compounds on the epinasty induced by 2,4-D was analysed in shoots and leaf strips from pea plants. For further insight into the effect of 2,4-D, studies were also made in Arabidopsis mutants deficient in ROS production (rbohD, rbohF, xdh), ethylene (ein 3-1, ctr 1-1, etr 1-1), abscisic acid (aba 3.1), and jasmonic acid (coi 1.1, jar 1.1, opr 3) pathways. The results suggest that ROS production, mainly ·OH, is essential in the development of epinasty triggered by 2,4-D. Epinasty was also found to be regulated by Ca2+, protein phosphorylation and ethylene, although all these factors act downstream of ROS production. The use of Arabidopsis mutants appears to indicate that abscisic and jasmonic acid are not involved in regulating epinasty, although they could be involved in other symptoms induced by 2,4-D.

  12. Reduction of hypervalent chromium in acidic media by alginic acid.

    PubMed

    Bertoni, Fernando A; Bellú, Sebastian E; González, Juan C; Sala, Luis F

    2014-12-19

    Selective oxidation of carboxylate groups present in alginic acid by Cr(VI) affords CO2, oxidized alginic acid, and Cr(III) as final products. The redox reaction afforded first-order kinetics in [alginic acid], [Cr(VI)], and [H(+)], at fixed ionic strength and temperature. Kinetic studies showed that the redox reaction proceeds through a mechanism which combines Cr(VI)→Cr(IV)→Cr(II) and Cr(VI)→Cr(IV)→Cr(III) pathways. The mechanism was supported by the observation of free radicals, CrO2(2+) and Cr(V) as reaction intermediates. The reduction of Cr(IV) and Cr(V) by alginic acid was independently studied and it was found to occur more than 10(3) times faster than alginic acid/Cr(VI) reaction, in acid media. At pH 1-3, oxo-chromate(V)-alginic acid species remain in solution during several hours at 15°C. The results showed that this abundant structural polysaccharide present on brown seaweeds is able to reduce Cr(VI/V/IV) or stabilize high-valent chromium depending on pH value.

  13. Acid hydrolysis of sugarcane bagasse for lactic acid production.

    PubMed

    Laopaiboon, Pattana; Thani, Arthit; Leelavatcharamas, Vichean; Laopaiboon, Lakkana

    2010-02-01

    In order to use sugarcane bagasse as a substrate for lactic acid production, optimum conditions for acid hydrolysis of the bagasse were investigated. After lignin extraction, the conditions were varied in terms of hydrochloric (HCl) or sulfuric (H(2)SO(4)) concentration (0.5-5%, v/v), reaction time (1-5h) and incubation temperature (90-120 degrees C). The maximum catalytic efficiency (E) was 10.85 under the conditions of 0.5% of HCl at 100 degrees C for 5h, which the main components (in gl(-1)) in the hydrolysate were glucose, 1.50; xylose, 22.59; arabinose, 1.29; acetic acid, 0.15 and furfural, 1.19. To increase yield of lactic acid production from the hydrolysate by Lactococcus lactis IO-1, the hydrolysate was detoxified through amberlite and supplemented with 7 g l(-1) of xylose and 7 g l(-1) of yeast extract. The main products (in gl(-1)) of the fermentation were lactic acid, 10.85; acetic acid, 7.87; formic acid, 6.04 and ethanol, 5.24.

  14. New insights into the regulation of plant immunity by amino acid metabolic pathways.

    PubMed

    Zeier, Jürgen

    2013-12-01

    Besides defence pathways regulated by classical stress hormones, distinct amino acid metabolic pathways constitute integral parts of the plant immune system. Mutations in several genes involved in Asp-derived amino acid biosynthetic pathways can have profound impact on plant resistance to specific pathogen types. For instance, amino acid imbalances associated with homoserine or threonine accumulation elevate plant immunity to oomycete pathogens but not to pathogenic fungi or bacteria. The catabolism of Lys produces the immune signal pipecolic acid (Pip), a cyclic, non-protein amino acid. Pip amplifies plant defence responses and acts as a critical regulator of plant systemic acquired resistance, defence priming and local resistance to bacterial pathogens. Asp-derived pyridine nucleotides influence both pre- and post-invasion immunity, and the catabolism of branched chain amino acids appears to affect plant resistance to distinct pathogen classes by modulating crosstalk of salicylic acid- and jasmonic acid-regulated defence pathways. It also emerges that, besides polyamine oxidation and NADPH oxidase, Pro metabolism is involved in the oxidative burst and the hypersensitive response associated with avirulent pathogen recognition. Moreover, the acylation of amino acids can control plant resistance to pathogens and pests by the formation of protective plant metabolites or by the modulation of plant hormone activity.

  15. Acid soil and acid rain, 2nd edition

    SciTech Connect

    Kennedy, I.R.

    1992-01-01

    This book examines the basic chemical processes involved in acidification in order to better assess their long-term effects on the status of soils, the health of plants and other living species that depend on them. It also discusses acidity, pH and protons their significance in bioenergetics and the consequent role of autotrophic organisms in acidifying ecosystems. This edition incorporates and integrates recent findings that render more explanations of the causes of the environmental impacts of acidity, especially in forests and lakes. Also explores current research into acid rain and soil in order to devise appropriate measures for their amelioration.

  16. The Amidohydrolases IAR3 and ILL6 Contribute to Jasmonoyl-Isoleucine Hormone Turnover and Generate 12-Hydroxyjasmonic Acid Upon Wounding in Arabidopsis Leaves*

    PubMed Central

    Widemann, Emilie; Miesch, Laurence; Lugan, Raphaël; Holder, Emilie; Heinrich, Clément; Aubert, Yann; Miesch, Michel; Pinot, Franck; Heitz, Thierry

    2013-01-01

    Jasmonates (JAs) are a class of signaling compounds that mediate complex developmental and adaptative responses in plants. JAs derive from jasmonic acid (JA) through various enzymatic modifications, including conjugation to amino acids or oxidation, yielding an array of derivatives. The main hormonal signal, jasmonoyl-l-isoleucine (JA-Ile), has been found recently to undergo catabolic inactivation by cytochrome P450-mediated oxidation. We characterize here two amidohydrolases, IAR3 and ILL6, that define a second pathway for JA-Ile turnover during the wound response in Arabidopsis leaves. Biochemical and genetic evidence indicates that these two enzymes cleave the JA-Ile signal, but act also on the 12OH-JA-Ile conjugate. We also show that unexpectedly, the abundant accumulation of tuberonic acid (12OH-JA) after wounding originates partly through a sequential pathway involving (i) conjugation of JA to Ile, (ii) oxidation of the JA-Ile conjugate, and (iii) cleavage under the action of the amidohydrolases. The coordinated actions of oxidative and hydrolytic branches in the jasmonate pathway highlight novel mechanisms of JA-Ile hormone turnover and redefine the dynamic metabolic grid of jasmonate conversion in the wound response. PMID:24052260

  17. Fatty acid composition of selected prosthecate bacteria.

    PubMed

    Carter, R N; Schmidt, J M

    1976-10-11

    The cellular fatty acid composition of 14 strains of Caulobacter speices and types, two species of Prosthecomicrobium, and two species of Asticcacaulis was determined by gas-liquid chromatography. In most of these bacteria, the major fatty acids were octadecenoic acid (C18:1), hexadecenoic acid (C16:1) and hexadecanoic acid (C16:0). Some cyclopropane and branched chain fatty acids were detected in addition to the straight chained acids. Hydroxytetradecanoic acid was an important component of P.enhydrum but significant amounts of hydroxy acids were not detected in other prosthecate bacteria examined.

  18. Functional nucleic acid probes and uses thereof

    DOEpatents

    Nilsen-Hamilton, Marit

    2006-10-03

    The present invention provides functional nucleic acid probes, and methods of using functional nucleic acid probes, for binding a target to carry out a desired function. The probes have at least one functional nucleic acid, at least one regulating nucleic acid, and at least one attenuator. The functional nucleic acid is maintained in an inactive state by the attenuator and activated by the regulating nucleic acid only in the presence of a regulating nucleic acid target. In its activated state the functional nucleic acid can bind to its target to carry out a desired function, such as generating a signal, cleaving a nucleic acid, or catalyzing a reaction.

  19. Evaluation of clastogenicity of formic acid, acetic acid and lactic acid on cultured mammalian cells.

    PubMed

    Morita, T; Takeda, K; Okumura, K

    1990-03-01

    Using Chinese hamster ovary K1 cells, chromosomal aberration tests were carried out with formic acid, acetic acid and lactic acid, and the relationship between the pH of the medium and the clastogenic activity was examined. The medium used was Ham's F12 supplemented with 17 mM NaHCO3 and 10% fetal calf serum. All of these acids induced chromosomal aberrations at the initial pH of ca. 6.0 or below (about 10-14 mM of each acid) both with and without S9 mix. Exposure of cells to about pH 5.7 or below (about 12-16 mM of each acid) was found to be toxic. When the culture medium was first acidified with each of these acids and then neutralized to pH 6.4 or pH 7.2 with NaOH, no clastogenic activity was observed. Using F12 medium supplemented with 34 mM NaHCO3 as a buffer, no clastogenic activity was observed at doses up to 25 mM of these acids (initial pH 5.8-6.0). However, it was found that about 10% of the cells had aberrations at pH 5.7 or below (27.5-32.5 mM of each acid). Furthermore, when 30 mM HEPES was used as a buffer, chromosomal aberrations were not induced at doses up to 20 mM formic acid and acetic acid (initial pH 7.0-7.1), and at doses up to 30 mM lactic acid (initial pH 6.6). In the initial pH range of 6.4-6.7 (25-32.5 mM of each acid), chromosomal aberrations were observed. The above results show that these acids themselves are non-clastogenic, and the pseudo-positive reactions attributable to non-physiological pH could be eliminated by either neutralization of the treatment medium or enhancement of the buffering ability.

  20. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...