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Sample records for acid myo-inositol hexakisphosphate

  1. Lactic acid and thermal treatments trigger the hydrolysis of myo-inositol hexakisphosphate and modify the abundance of lower myo-inositol phosphates in barley (Hordeum vulgare L.).

    PubMed

    Metzler-Zebeli, Barbara U; Deckardt, Kathrin; Schollenberger, Margit; Rodehutscord, Markus; Zebeli, Qendrim

    2014-01-01

    Barley is an important source of dietary minerals, but it also contains myo-inositol hexakisphosphate (InsP6) that lowers their absorption. This study evaluated the effects of increasing concentrations (0.5, 1, and 5%, vol/vol) of lactic acid (LA), without or with an additional thermal treatment at 55°C (LA-H), on InsP6 hydrolysis, formation of lower phosphorylated myo-inositol phosphates, and changes in chemical composition of barley grain. Increasing LA concentrations and thermal treatment linearly reduced (P<0.001) InsP6-phosphate (InsP6-P) by 0.5 to 1 g compared to the native barley. In particular, treating barley with 5% LA-H was the most efficient treatment to reduce the concentrations of InsP6-P, and stimulate the formation of lower phosphorylated myo-inositol phosphates such as myo-inositol tetraphosphate (InsP4) and myo-inositol pentaphosphates (InsP5). Also, LA and thermal treatment changed the abundance of InsP4 and InsP5 isomers with Ins(1,2,5,6)P4 and Ins(1,2,3,4,5)P5 as the dominating isomers with 5% LA, 1% LA-H and 5% LA-H treatment of barley, resembling to profiles found when microbial 6-phytase is applied. Treating barley with LA at room temperature (22°C) increased the concentration of resistant starch and dietary fiber but lowered those of total starch and crude ash. Interestingly, total phosphorus (P) was only reduced (P<0.05) in barley treated with LA-H but not after processing of barley with LA at room temperature. In conclusion, LA and LA-H treatment may be effective processing techniques to reduce InsP6 in cereals used in animal feeding with the highest degradation of InsP6 at 5% LA-H. Further in vivo studies are warranted to determine the actual intestinal P availability and to assess the impact of changes in nutrient composition of LA treated barley on animal performance.

  2. Degradation of myo-inositol hexakisphosphate by a phytate-degrading enzyme from Pantoea agglomerans.

    PubMed

    Greiner, Ralf

    2004-11-01

    High-pressure liquid chromatography (HPLC) analysis established myo-inositol pentakisphosphate as the final product of phytate dephosphorylation by the phytate-degrading enzyme from Pantoea agglomerans. Neither product inhibition by phosphate nor inactivation of the Pantoea enzyme during the incubation period were responsible for the limited phytate hydrolysis as shown by addition of phytate-degrading enzyme and phytate, respectively, after the observed stop of enzymatic phytate degradation. In additon, the Pantoea enzyme did not possess activity toward the purified myo-inositol pentakisphosphate. Using a combination of High-Performance Ion Chromatography (HPIC) analysis and kinetic studies, the nature of the generated myo-inositol pentakisphosphate was established. The data demonstrate that the phytate-degrading enzyme from Pantoea agglomerans dephosphorylates myo-inositol hexakisphosphate in a stereospecific way to finally D-myo-inositol(1,2,4,5,6)pentakisphosphate.

  3. Stereospecificity of myo-inositol hexakisphosphate dephosphorylation by a phytate-degrading enzyme of baker's yeast.

    PubMed

    Greiner, R; Alminger, M L; Carlsson, N G

    2001-05-01

    During food processing such as baking, phytate is dephosphorylated to produce degradation products, such as myo-inositol pentakis-, tetrakis-, tris-, bis-, and monophosphates. Certain myo-inositol phosphates have been proposed to have positive effects on human health. The position of the phosphate groups on the myo-inositol ring is thereby of great significance for their physiological functions. Using a combination of high-performance ion chromatography analysis and kinetic studies the stereospecificity of myo-inositol hexakisphosphate dephosphorylation by a phytate-degrading enzyme from baker's yeast (Saccharomyces cerevisiae) was established. The data demonstrate that the phytate-degrading enzyme from baker's yeast dephosphorylates myo-inositol hexakisphosphate in a stereospecific way by sequential removal of phosphate groups via D-Ins(1,2,4,5,6)P(5), D-Ins(1,2,5,6)P(4), D-Ins(1,2,6)P(3), D-Ins(1,2)P(2), to finally Ins(2)P (notation 3/4/5/6/1). Knowledge of the absolute stereochemical specificity of the baker's yeast phytase allows use of the enzyme to produce defined myo-inositol phosphates for kinetic and physiological studies.

  4. Biochemical characterization of fungal phytases (myo-inositol hexakisphosphate phosphohydrolases): catalytic properties.

    PubMed

    Wyss, M; Brugger, R; Kronenberger, A; Rémy, R; Fimbel, R; Oesterhelt, G; Lehmann, M; van Loon, A P

    1999-02-01

    Supplementation with phytase is an effective way to increase the availability of phosphorus in seed-based animal feed. The biochemical characteristics of an ideal phytase for this application are still largely unknown. To extend the biochemical characterization of wild-type phytases, the catalytic properties of a series of fungal phytases, as well as Escherichia coli phytase, were determined. The specific activities of the fungal phytases at 37 degreesC ranged from 23 to 196 U. (mg of protein)-1, and the pH optima ranged from 2.5 to 7.0. When excess phytase was used, all of the phytases were able to release five phosphate groups of phytic acid (myo-inositol hexakisphosphate), which left myo-inositol 2-monophosphate as the end product. A combination consisting of a phytase and Aspergillus niger pH 2.5 acid phosphatase was able to liberate all six phosphate groups. When substrate specificity was examined, the A. niger, Aspergillus terreus, and E. coli phytases were rather specific for phytic acid. On the other hand, the Aspergillus fumigatus, Emericella nidulans, and Myceliophthora thermophila phytases exhibited considerable activity with a broad range of phosphate compounds, including phenyl phosphate, p-nitrophenyl phosphate, sugar phosphates, alpha- and beta-glycerophosphates, phosphoenolpyruvate, 3-phosphoglycerate, ADP, and ATP. Both phosphate liberation kinetics and a time course experiment in which high-performance liquid chromatography separation of the degradation intermediates was used showed that all of the myo-inositol phosphates from the hexakisphosphate to the bisphosphate were efficiently cleaved by A. fumigatus phytase. In contrast, phosphate liberation by A. niger or A. terreus phytase decreased with incubation time, and the myo-inositol tris- and bisphosphates accumulated, suggesting that these compounds are worse substrates than phytic acid is. To test whether broad substrate specificity may be advantageous for feed application, phosphate

  5. Analysis of myo-inositol hexakisphosphate hydrolysis by Bacillus phytase: indication of a novel reaction mechanism.

    PubMed

    Kerovuo, J; Rouvinen, J; Hatzack, F

    2000-12-15

    Phytic acid (myo-inositol hexakisphosphate, InsP(6)) hydrolysis by Bacillus phytase (PhyC) was studied. The enzyme hydrolyses only three phosphates from phytic acid. Moreover, the enzyme seems to prefer the hydrolysis of every second phosphate over that of adjacent ones. Furthermore, it is very likely that the enzyme has two alternative pathways for the hydrolysis of phytic acid, resulting in two different myo-inositol trisphosphate end products: Ins(2,4,6)P(3) and Ins(1,3,5)P(3). These results, together with inhibition studies with fluoride, vanadate, substrate and a substrate analogue, indicate a reaction mechanism different from that of other phytases. By combining the data presented in this study with (1) structural information obtained from the crystal structure of Bacillus amyloliquefaciens phytase [Ha, Oh, Shin, Kim, Oh, Kim, Choi and Oh (2000) Nat. Struct. Biol. 7, 147-153], and (2) computer-modelling analyses of enzyme-substrate complexes, a novel mode of phytic acid hydrolysis is proposed.

  6. Stereospecificity of myo-inositol hexakisphosphate dephosphorylation by a phytate-degrading enzyme of Escherichia coli.

    PubMed

    Greiner, R; Carlsson, N; Alminger, M L

    2001-11-17

    Using a combination of high-performance ion chromatography analysis and kinetic studies, the stereospecificity of myo-inositol hexakisphosphate dephosphorylation by the phytate-degrading enzyme P2 of Escherichia coli was established. High-performance ion chromatography revealed that the phytate-degrading enzyme P2 of E. coli degrades myo-inositol hexakisphosphate by stepwise dephosphorylation via D/L-Ins(1,2,3,4,5)P(5), D/L-Ins(2,3,4,5)P(4), D/L-Ins(2,4,5)P(3) or D/L-Ins(1,2,4)P(3), D/L-Ins(1,2)P(2) or Ins(2, 5)P(2) or D/L-Ins(4,5)P(2) to finally Ins(2)P or Ins(5)P. Kinetic parameters for myo-inositol pentakisphosphate hydrolysis by E. coli and wheat phytase, respectively, showed that the myo-inositol pentakisphosphate intermediate produced either by the phytate-degrading enzyme of wheat or E. coli are not identical. The absolute configuration of the myo-inositol pentakisphosphate isomer produced by the E. coli enzyme was determined by taking into consideration that wheat phytase produces predominantly the D-Ins(1, 2,3,5,6)P(5) isomer (Lim, P.E., Tate, M.E., 1973. The phytases: II. Properties of phytase fraction F(1) and F(2) from wheat bran and the myo-inositol phosphates produced by fraction F(2). Biochim. Biophys. Acta 302, 326-328). The data demonstrate that the phytate-degrading enzyme P2 of E. coli dephosphorylates myo-inositol hexakisphosphate in a stereospecific way by sequential removal of phosphate groups via D-Ins(1,2,3,4,5)P(5), D-Ins(2,3,4,5)P(4), D-Ins(2,4,5)P(3), Ins(2,5)P(2) to finally Ins(2)P (notation 6/1/3/4/5).

  7. Characterization of myo-inositol hexakisphosphate deposits from larval Echinococcus granulosus.

    PubMed

    Casaravilla, Cecilia; Brearley, Charles; Soulé, Silvia; Fontana, Carolina; Veiga, Nicolás; Bessio, María I; Ferreira, Fernando; Kremer, Carlos; Díaz, Alvaro

    2006-07-01

    The abundant metabolite myo-inositol hexakisphosphate (InsP6) can form vesicular deposits with cations, a widespread phenomenon in plants also found in the cestode parasite, Echinococcus granulosus. In this organism, the deposits are exocytosed, accumulating in a host-exposed sheath of extracellular matrix termed the laminated layer. The formation and mobilization of InsP6 deposits, which involve precipitation and solubilization reactions, respectively, cannot yet be rationalized in quantitative chemical terms, as the solids involved have not been formally described. We report such a description for the InsP6 deposits from E. granulosus, purified as the solid residue left by mild alkaline digestion of the principal mucin component of the laminated layer. The deposits are largely composed of the compound Ca5H2L.16H2O (L representing fully deprotonated InsP6), and additionally contain Mg2+ (6-9% molar ratio with respect to Ca2+), but not K+. Calculations employing recently available chemical constants show that the precipitation of Ca5H2L.16H2O is predicted by thermodynamics in secretory vesicle-like conditions. The deposits appear to be similar to microcrystalline solids when analysed under the electron microscope; we estimate that each crystal comprises around 200 InsP6 molecules. We calculate that the deposits increase, by three orders of magnitude, the surface area available for adsorption of host proteins, a salient ability of the laminated layer. The major inositol phosphate in the deposits, other than InsP6, is myo-inositol (1,2,4,5,6) pentakisphosphate, or its enantiomer, inositol (2,3,4,5,6) pentakisphosphate. The compound appears to be a subproduct of the intracellular pathways leading to the synthesis and vesicular accumulation of InsP6, rather than arising from extracellular hydrolysis of InsP6.

  8. Broad Spectrum Anticancer Activity of Myo-Inositol and Inositol Hexakisphosphate

    PubMed Central

    Dinicola, Simona

    2016-01-01

    Inositols (myo-inositol and inositol hexakisphosphate) exert a wide range of critical activities in both physiological and pathological settings. Deregulated inositol metabolism has been recorded in a number of diseases, including cancer, where inositol modulates different critical pathways. Inositols inhibit pRB phosphorylation, fostering the pRB/E2F complexes formation and blocking progression along the cell cycle. Inositols reduce PI3K levels, thus counteracting the activation of the PKC/RAS/ERK pathway downstream of PI3K activation. Upstream of that pathway, inositols disrupt the ligand interaction between FGF and its receptor as well as with the EGF-transduction processes involving IGF-II receptor and AP-1 complexes. Additionally, Akt activation is severely impaired upon inositol addition. Downregulation of both Akt and ERK leads consequently to NF-kB inhibition and reduced expression of inflammatory markers (COX-2 and PGE2). Remarkably, inositol-induced downregulation of presenilin-1 interferes with the epithelial-mesenchymal transition and reduces Wnt-activation, β-catenin translocation, Notch-1, N-cadherin, and SNAI1 release. Inositols interfere also with the cytoskeleton by upregulating Focal Adhesion Kinase and E-cadherin and decreasing Fascin and Cofilin, two main components of pseudopodia, leading hence to invasiveness impairment. This effect is reinforced by the inositol-induced inhibition on metalloproteinases and ROCK1/2 release. Overall, these effects enable inositols to remodel the cytoskeleton architecture. PMID:27795708

  9. A protein tyrosine phosphatase-like inositol polyphosphatase from Selenomonas ruminantium subsp. lactilytica has specificity for the 5-phosphate of myo-inositol hexakisphosphate.

    PubMed

    Puhl, Aaron A; Greiner, Ralf; Selinger, L Brent

    2008-01-01

    Although it is becoming well known that myo-inositol polyphosphates and the enzymes involved in their metabolism play a critical role in eukaryotic systems, little is understood of their significance in prokaryotic systems. A novel protein tyrosine phosphatase (PTP)-like inositol polyphosphatase (IPPase) gene has been cloned from Selenomonas ruminantium subsp. lactilytica (phyAsrl). The deduced amino acid sequence of PhyAsrl is most similar to a PTP-like IPPase from the anaerobic bacterium S. ruminantium (35% identity), but also shows similarity (19-30% identity) to various other putative prokaryotic PTPs. Recombinant PhyAsrl could dephosphorylate myo-inositol hexakisphosphate (Ins P(6)) in vitro, and maximal activity was displayed at an ionic strength of 200 mM, a pH of 4.5, and a temperature of 55 degrees C. In order to elucidate its substrate specificity and pathway of Ins P(6) dephosphorylation, a combination of kinetic and high-performance ion-pair chromatography studies were conducted. The data indicated that PhyAsrl has a general specificity for polyphosphorylated myo-inositol substrates, but can also dephosphorylate molecules containing high energy pyrophosphate bonds in vitro. PhyAsrl is unique from other microbial IPPases in that it preferentially cleaves the 5-phosphate position of Ins P(6). Furthermore, it can produce Ins(2)P via a highly unique and ordered pathway of sequential dephosphorylation: Ins P(6), Ins(1,2,3,4,6)P(5), D-Ins(1,2,3,6)P(4), Ins(1,2,3)P(3), and D/L-Ins(1,2)P(2). Finally, reverse transcription PCR was used to determine that phyAsrl is constitutively expressed, and together with bioinformatic analysis, was used to gain an understanding of its physiological significance.

  10. Stereospecificity of myo-inositol hexakisphosphate hydrolysis by a protein tyrosine phosphatase-like inositol polyphosphatase from Megasphaera elsdenii.

    PubMed

    Puhl, Aaron A; Greiner, Ralf; Selinger, L Brent

    2009-02-01

    Inositol polyphosphatases (IPPases), particularly those that can hydrolyze myo-inositol hexakisphosphate (Ins P(6)), are of biotechnological interest for their ability to reduce the metabolically unavailable organic phosphate content of feedstuffs and to produce lower inositol polyphosphates (IPPs) for research and pharmaceutical applications. Here, the gene coding for a new protein tyrosine phosphatase (PTP)-like IPPase was cloned from Megasphaera elsdenii (phyAme), and the biochemical properties of the recombinant protein were determined. The deduced amino acid sequence of PhyAme is similar to known PTP-like IPPases (29-44% identity), and the recombinant enzyme displayed strict specificity for IPP substrates. Optimal IPPase activity was displayed at an ionic strength of 250 mM, a pH of 5.0, and a temperature of 60 degrees C. In order to elucidate its stereospecificity of Ins P(6) dephosphorylation, a combination of high-performance ion-pair chromatography and kinetic studies was conducted. PhyAme displayed a stereospecificity that is unique among enzymes belonging to this class in that it preferentially cleaved Ins P(6) at one of two phosphate positions, 1D-3 or 1D-4. PhyAme followed two distinct and specific routes of hydrolysis, predominantly degrading Ins P(6) to Ins(2)P via: (a) 1D-Ins(1,2,4,5,6)P(5), 1D-Ins(1,2,5,6)P(4), 1D-Ins(1,2,6)P(3), and 1D-Ins(1,2)P(2) (60%) and (b) 1D-Ins(1,2,3,5,6)P(5), 1D-Ins(1,2,3,6)P(4), Ins(1,2,3)P(3), and D/L-Ins(1,2)P(2)(35%).

  11. Phytic acid and myo-inositol support adipocyte differentiation and improve insulin sensitivity in 3T3-L1 cells.

    PubMed

    Kim, Jin Nam; Han, Sung Nim; Kim, Hye-Kyeong

    2014-08-01

    Phytic acid, also known as myo-inositol hexaphosphate, has been shown to lower blood glucose levels and to improve insulin sensitivity in rodents. We investigated the effects of phytic acid and myo-inositol on differentiation, insulin-stimulated glucose uptake, and lipolysis of adipocytes to test the hypothesis that the antidiabetic properties of phytic acid and myo-inositol are mediated directly through adipocytes. 3T3-L1 cells were treated with 10, 50, or 200 μmol/L of phytic acid or myo-inositol. Oil Red O staining and an intracellular triacylglycerol assay were used to determine lipid accumulation during adipocyte differentiation. Immunoblotting and real-time polymerase chain reaction (PCR) were performed to evaluate expression of transcription factors, a target protein, and insulin signaling molecules. Phytic acid and myo-inositol exposures increased lipid accumulation in a dose-dependent manner (P < .01). The expression of key transcription factors associated with adipocyte differentiation, such as peroxisome proliferator-activated receptor γ (PPARγ) and sterol regulatory element-binding protein 1c, and the expression of fatty acid synthase increased upon treatments with phytic acid and myo-inositol (P < .05). Insulin-stimulated glucose uptake in mature adipocytes increased with phytic acid and myo-inositol treatments (P < .01). In addition, mRNA levels of insulin receptor substrate 1 (IRS1), mRNA levels of glucose transporter 4, and phosphorylation of tyrosine in IRS1 increased upon phytic acid and myo-inositol treatments. In fully differentiated adipocytes, phytic acid and myo-inositol reduced basal lipolysis dose dependently (P < .01). These results suggest that phytic acid and myo-inositol increase insulin sensitivity in adipocytes by increasing lipid storage capacity, improving glucose uptake, and inhibiting lipolysis.

  12. Unique precipitation and exocytosis of a calcium salt of myo-inositol hexakisphosphate in larval Echinococcus granulosus.

    PubMed

    Irigoín, Florencia; Casaravilla, Cecilia; Iborra, Francisco; Sim, Robert B; Ferreira, Fernando; Díaz, Alvaro

    2004-12-15

    The ubiquitous intracellular molecule myo-inositol hexakisphosphate (IP6) is present extracellularly in the hydatid cyst wall (HCW) of the parasitic cestode Echinococcus granulosus. This study shows that extracellular IP6 is present as its solid calcium salt, in the form of deposits that are observed, at the ultrastructural level, as naturally electron dense granules some tens of nanometers in diameter. The presence of a calcium salt of IP6 in these structures was determined by two different electron microscopy techniques: (i) the analysis of the spatial distribution of phosphorus and calcium in the outer, acellular layer of the HCW (the laminated layer, LL) through electron energy loss spectroscopy, and (ii) the observation, by transmission electron microscopy, of HCW that were selectively depleted of IP6 by treatment with EGTA or phytase, an enzyme that catalyses the dephosphorylation of IP6. The deposits of the IP6-Ca(II) salt are also observed inside membrane vesicles in cells of the germinal layer (the inner, cellular layer of the HCW), indicating that IP6 precipitates with calcium within a cellular vesicular compartment and is then secreted to the LL. Thus, much as in plants (that produce vesicular IP6 deposits), the existence of transporters for IP6 or its precursors in internal membranes is needed to explain the compound's cellular localisation in E. granulosus.

  13. myo-Inositol hexakisphosphate is a major component of an extracellular structure in the parasitic cestode Echinococcus granulosus.

    PubMed Central

    Irigoín, Florencia; Ferreira, Fernando; Fernández, Cecilia; Sim, Robert B; Díaz, Alvaro

    2002-01-01

    myo-Inositol hexakisphosphate (IP(6)) is an abundant intracellular component of animal cells. In this study we describe the presence of extracellular IP(6) in the hydatid cyst wall (HCW) of the larval stage of the cestode parasite Echinococcus granulosus. The HCW comprises an inner cellular layer and an outer, acellular (laminated) layer up to 2 mm in thickness that protects the parasite from host immune cells. A compound, subsequently identified as IP(6), was detected in and purified from an HCW extract on the basis of its capacity to inhibit complement activation. The identification of the isolated compound was carried out by a combination of NMR, MS and TLC. The majority of IP(6) in the HCW was found in the acellular layer, with only a small fraction of the compound being extracted from cells. In the laminated layer, IP(6) was present in association with calcium, and accounted for up to 15% of the total dry mass of the HCW. IP(6) was not detected in any other structures or stages of the parasite. Our results imply that IP(6) is secreted by the larval stage of the parasite in a polarized fashion towards the interface with the host. This is the first report of the secretion of IP(6), and the possible implications beyond the biology of E. granulosus are discussed. PMID:11853537

  14. Size-dependent sorption of myo-inositol hexakisphosphate and orthophosphate on nano-γ-Al2O3.

    PubMed

    Yan, Yupeng; Koopal, Luuk K; Li, Wei; Zheng, Anmin; Yang, Jun; Liu, Fan; Feng, Xionghan

    2015-08-01

    The effects of particle size (5, 35 and 70nm) on the sorption of myo-inositol hexakisphosphate (IHP) and inorganic phosphate (KH2PO4, Pi) on γ-Al2O3 nanoparticles were investigated using batch sorption experiments, zeta potential measurements and solid-state nuclear magnetic resonance spectroscopy (NMR). The results show that the maximum sorption densities (μmolm(-2)) for IHP and Pi increase with decreasing γ-Al2O3 particle size. The sorption affinity of γ-Al2O3 for IHP and Pi generally increases with decreasing particle size, and the sorption affinity for IHP is approximately one order of magnitude greater than that for Pi. In our experimental time scale, surface complexation is the main mechanism for IHP and Pi sorption on large size γ-Al2O3. While an additional surface precipitation mechanism, indicated by solid-state (31)P and (27)Al NMR data, is partly responsible for the greater sorption density on very small size γ-Al2O3. Compared with Pi, the effect of particle size on the sorption of IHP is more pronounced. The results suggest a size-dependent surface reactivity of Al2O3 nanoparticles with Pi/IHP. The underlying mechanism will also be relevant for other small nanosize (hydr)oxide particles and is important for our understanding of the role of small nanoparticles in controlling the mobility and fate of organic and inorganic phosphates in the environment.

  15. Myo-inositol hexakisphosphate degradation by Bifidobacterium pseudocatenulatum ATCC 27919 improves mineral availability of high fibre rye-wheat sour bread.

    PubMed

    García-Mantrana, Izaskun; Monedero, Vicente; Haros, Monika

    2015-07-01

    The goal of this investigation was to develop baking products using Bifidobacterium pseudocatenulatum ATCC27919, a phytase producer, as a starter in sourdough for the production of whole rye-wheat mixed bread. This Bifidobacterium strain contributed to myo-inositol hexakisphosphate (phytate) hydrolysis, resulting in breads with higher mineral availability as was predicted by the phytate/mineral molar ratios, which remained below the inhibitory threshold values for Ca and Zn intestinal absorption. The products with sourdough showed similar technological quality as their homologous without sourdough, with levels of acetic and d/l lactic acids in dough and bread baking significantly higher with the use of sourdough. The overall acceptability scores showed that breads with 25% of whole rye flour were highly accepted regardless of the inclusion of sourdough. This work emphasises that the in situ production of phytase during fermentation by GRAS/QPS microorganisms constitutes a strategy which is particularly appropriate for reducing the phytate contents in products for human consumption.

  16. Myo-inositol esters of indole-3-acetic acid are endogenous components of Zea mays L. shoot tissue

    NASA Technical Reports Server (NTRS)

    Chisnell, J. R.

    1984-01-01

    Indole-3-acetyl-myo-inositol esters have been demonstrated to be endogenous components of etiolated Zea mays shoots tissue. This was accomplished by comparison of the putative compounds with authentic, synthetic esters. The properties compared were liquid and gas-liquid chromatographic retention times and the 70-ev mass spectral fragmentation pattern of the pentaacetyl derivative. The amount of indole-3-acetyl-myo-inositol esters in the shoots was determined to be 74 nanomoles per kilogram fresh weight as measured by isotope dilution, accounting for 19% of the ester indole-3-acetic acid of the shoot. This work is the first characterization of an ester conjugate of indole-3-acetate acid from vegetative shoot tissue using multiple chromatographic properties and mass spectral identification. The kernel and the seedling shoot both contain indole-3-acetyl-myo-inositol esters, and these esters comprise approximately the same percentage of the total ester content of the kernel and of the shoot.

  17. A defect in sodium-dependent amino acid uptake in diabetic rabbit peripheral nerve. Correction by an aldose reductase inhibitor or myo-inositol administration.

    PubMed Central

    Greene, D A; Lattimer, S A; Carroll, P B; Fernstrom, J D; Finegold, D N

    1990-01-01

    A myo-inositol-related defect in nerve sodium-potassium ATPase activity in experimental diabetes has been suggested as a possible pathogenetic factor in diabetic neuropathy. Because the sodium-potassium ATPase is essential for other sodium-cotransport systems, and because myo-inositol-derived phosphoinositide metabolites regulate multiple membrane transport processes, sodium gradient-dependent amino acid uptake was examined in vitro in endoneurial preparations derived from nondiabetic and 14-d alloxan diabetic rabbits. Untreated alloxan diabetes reduced endoneurial sodium-gradient dependent uptake of the nonmetabolized amino acid 2-aminoisobutyric acid by greater than 50%. Administration of an aldose reductase inhibitor prevented reductions in both nerve myo-inositol content and endoneurial sodium-dependent 2-aminoisobutyric acid uptake. Myo-inositol supplementation that produced a transient pharmacological elevation in plasma myo-inositol concentration, but did not raise nerve myo-inositol content, reproduced the effect of the aldose reductase inhibitor on endoneurial sodium-dependent 2-aminoisobutyric acid uptake. Phorbol myristate acetate, which acutely normalizes sodium-potassium ATPase activity in diabetic nerve, did not acutely correct 2-aminoisobutyric uptake when added in vitro. These data suggest that depletion of a small myo-inositol pool may be implicated in the pathogenesis of defects in amino acid uptake in diabetic nerve and that rapid correction of sodium-potassium ATPase activity with protein kinase C agonists in vitro does not acutely normalize sodium-dependent 2-aminoisobutyric acid uptake. PMID:2185278

  18. Evaluation of in vitro and in vivo biocompatibility of a myo-inositol hexakisphosphate gelated polyaniline hydrogel in a rat model

    PubMed Central

    Sun, Kwang-Hsiao; Liu, Zhao; Liu, Changjian; Yu, Tong; Shang, Tao; Huang, Chen; Zhou, Min; Liu, Cheng; Ran, Feng; Li, Yun; Shi, Yi; Pan, Lijia

    2016-01-01

    Recent advances in understanding the interaction between electricity and cells/biomolecules have generated great interest in developing biocompatible electrically conductive materials. In this study, we investigated the biocompatibility of a myo-inositol hexakisphosphate gelated polyaniline hydrogel using in vitro and in vivo experiments in a rat model. The polyaniline hydrogel was used to coat a polycaprolactone scaffold and was cultured with rat endothelial progenitor cells differentiated from rat adipose-derived stem cells. Compared with the control sample on a pristine polycaprolactone scaffold, the treated polyaniline hydrogel had the same non-poisonous/cytotoxicity grade, enhanced cell adhesion, and a higher cell proliferation/growth rate. In implant studies, the polyaniline hydrogel sample induced milder inflammatory responses than did the control at the same time points. Combining the advantages of a biocompatible hydrogel and an organic conductor, the inositol phosphate-gelated polyaniline hydrogel could be used in bioelectronics applications such as biosensors, neural probes, cell stimulators, medical electrodes, tissue engineering, and electro-controlled drug delivery. PMID:27073144

  19. Evaluation of in vitro and in vivo biocompatibility of a myo-inositol hexakisphosphate gelated polyaniline hydrogel in a rat model

    NASA Astrophysics Data System (ADS)

    Sun, Kwang-Hsiao; Liu, Zhao; Liu, Changjian; Yu, Tong; Shang, Tao; Huang, Chen; Zhou, Min; Liu, Cheng; Ran, Feng; Li, Yun; Shi, Yi; Pan, Lijia

    2016-04-01

    Recent advances in understanding the interaction between electricity and cells/biomolecules have generated great interest in developing biocompatible electrically conductive materials. In this study, we investigated the biocompatibility of a myo-inositol hexakisphosphate gelated polyaniline hydrogel using in vitro and in vivo experiments in a rat model. The polyaniline hydrogel was used to coat a polycaprolactone scaffold and was cultured with rat endothelial progenitor cells differentiated from rat adipose-derived stem cells. Compared with the control sample on a pristine polycaprolactone scaffold, the treated polyaniline hydrogel had the same non-poisonous/cytotoxicity grade, enhanced cell adhesion, and a higher cell proliferation/growth rate. In implant studies, the polyaniline hydrogel sample induced milder inflammatory responses than did the control at the same time points. Combining the advantages of a biocompatible hydrogel and an organic conductor, the inositol phosphate-gelated polyaniline hydrogel could be used in bioelectronics applications such as biosensors, neural probes, cell stimulators, medical electrodes, tissue engineering, and electro-controlled drug delivery.

  20. myo-Inositol 1-Phosphate Synthase Inhibition and Control of Uridine Diphosphate-d-glucuronic Acid Biosynthesis in Plants 12

    PubMed Central

    Loewus, Mary W.; Loewus, Frank

    1974-01-01

    Of the eight intermediates associated with the two pathways of UDP-d-glucuronic acid biosynthesis found in plants, only d-glucuronic acid inhibited myo-inositol 1-phosphate synthase (EC 5.5.1.4), formerly referred to as d-glucose 6-phosphate cycloaldolase. Inhibition was competitive. An attempt to demonstrate over-all reversibility of the synthase indicated that it was less than 5% reversible, if at all. PMID:16658890

  1. Coordination, microprotonation equilibria and conformational changes of myo-inositol hexakisphosphate with pertinence to its biological function.

    PubMed

    Veiga, Nicolás; Torres, Julia; Macho, Israel; Gómez, Kerman; González, Gabriel; Kremer, Carlos

    2014-11-21

    Within all the eukaryotic cells there is an important group of biomolecules that has been potentially related to signalling functions: the myo-inositol phosphates (InsPs). In nature, the most abundant member of this family is the so called InsP6 (phytate, L(12-)), for which our group has strived in the past to elucidate its intricate chemical behaviour. In this work we expand on our earlier findings, shedding light on the inframolecular details of its protonation and complexation processes. We evaluate systematically the chemical performance of InsP6 in the presence and absence of alkali and alkaline earth metal ions, through (31)P NMR measurements, in a non-interacting medium and over a wide pH range. The analysis of the titration curves by means of a model based on the cluster expansion method allows us to describe in detail the distribution of the different protonated microspecies of the ligand. With the aid of molecular modelling tools, we assess the energetic and geometrical characteristics of the protonation sequence and the conformational transition suffered by InsP6 as the pH changes. By completely characterizing the protonation pattern, conformation and geometry of the metal complexes, we unveil the chemical and structural basis behind the influence that the physiologically relevant cations, Na(+), K(+), Mg(2+) and Ca(2+) have over the phytate chemical reactivity. This information is essential in the process of gaining reliable structural knowledge about the most important InsP6 species in the in vitro and in vivo experiments, and how these features modulate their probable biological functions.

  2. Partial purification and characterization of indol-3-ylacetylglucose:myo-inositol indol-3-ylacetyltransferase (indoleacetic acid-inositol synthase)

    NASA Technical Reports Server (NTRS)

    Kesy, J. M.; Bandurski, R. S.

    1990-01-01

    A procedure is described for the purification of the enzyme indol-3-ylacetylglucose:myo-inositol indol-3-ylacetyltransferase (IAA-myo-inositol synthase). This enzyme catalyzes the transfer of indol-3-ylacetate from 1-0-indol-3-ylacetyl-beta-d-glucose to myo-inositol to form indol-3-ylacetyl-myo-inositol and glucose. A hexokinase or glucose oxidase based assay system is described. The enzyme has been purified approximately 16,000-fold, has an isoelectric point of pH 6.1 and yields three catalytically inactive bands upon acrylamide gel electrophoresis of the native protein. The enzyme shows maximum transferase activity with myo-inositol but shows some transferase activity with scyllo-inositol and myo-inosose-2. No transfer of IAA occurs with myo-inositol-d-galactopyranose, cyclohexanol, mannitol, or glycerol as acyl acceptor. The affinity of the enzyme for 1-0-indol-3-ylacetyl-beta-d-glucose is, Km = 30 micromolar, and for myo-inositol is, Km = 4 millimolar. The enzyme does not catalyze the exchange incorporation of glucose into IAA-glucose indicating the reaction mechanism involves binding of IAA glucose to the enzyme with subsequent hydrolytic cleavage of the acyl moiety by the hydroxyl of myo-inositol to form IAA myo-inositol ester.

  3. Translocation of radiolabeled indole-3-acetic acid and indole-3-acetyl-myo-inositol from kernel to shoot of Zea mays L

    NASA Technical Reports Server (NTRS)

    Chisnell, J. R.; Bandurski, R. S.

    1988-01-01

    Either 5-[3H]indole-3-acetic acid (IAA) or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm of kernels of dark-grown Zea mays seedlings. The distribution of total radioactivity, radiolabeled indole-3-acetic acid, and radiolabeled ester conjugated indole-3-acetic acid, in the shoots was then determined. Differences were found in the distribution and chemical form of the radiolabeled indole-3-acetic acid in the shoot depending upon whether 5-[3H]indole-3-acetic acid or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm. We demonstrated that indole-3-acetyl-myo-inositol applied to the endosperm provides both free and ester conjugated indole-3-acetic acid to the mesocotyl and coleoptile. Free indole-3-acetic acid applied to the endosperm supplies some of the indole-3-acetic acid in the mesocotyl but essentially no indole-3-acetic acid to the coleoptile or primary leaves. It is concluded that free IAA from the endosperm is not a source of IAA for the coleoptile. Neither radioactive indole-3-acetyl-myo-inositol nor IAA accumulates in the tip of the coleoptile or the mesocotyl node and thus these studies do not explain how the coleoptile tip controls the amount of IAA in the shoot.

  4. Repeat length variation in the 5'UTR of myo-inositol monophosphatase gene is related to phytic acid content and contributes to drought tolerance in chickpea (Cicer arietinum L.).

    PubMed

    Joshi-Saha, Archana; Reddy, Kandali S

    2015-09-01

    Myo-inositol metabolism plays a significant role in plant growth and development, and is also used as a precursor for many important metabolites, such as ascorbate, pinitol, and phytate. Phytate (inositol hexakisphosphate) is the major storage pool for phosphate in the seeds. It is utilized during seed germination and growth of the developing embryo. In addition, it is implicated in protection against oxidative stress. In the present study, a panel of chickpea accessions was used for an association analysis. Association analysis accounting for population structure and relative kinship identified alleles of a simple sequence repeat marker, NCPGR90, that are associated with both phytic acid content and drought tolerance. These alleles varied with respect to the dinucleotide CT repeats present within the marker. NCPGR90 located to the 5'UTR of chickpea myo-inositol monophosphatase gene (CaIMP) and showed transcript length variation in drought-tolerant and drought-susceptible accessions. CaIMP from a drought-tolerant accession with a smaller repeat was almost 2-fold upregulated as compared to a susceptible accession having a longer repeat, even under control non-stressed conditions. This study suggests an evolution of simple sequence repeat length variation in CaIMP, which might be regulating phytic acid levels to confer drought tolerance in natural populations of chickpea.

  5. Studies on the properties of myo-inositol-1,4,5-trisphosphate 5-phosphatase and myo-inositol monophosphatase in bovine iris sphincter smooth muscle: effects of okadaic acid and protein phosphorylation.

    PubMed

    Wang, X L; Akhtar, R A; Abdel-Latif, A A

    1994-05-26

    In bovine iris sphincter, myo-inositol 1,4,5-trisphosphate (IP3) 5-phosphatase and myo-inositol 1-phosphate (IP1) monophosphatase are mainly localized in the microsomal and soluble fractions, respectively. Studies on the properties of these enzymes can be summarized as follows. (1) The microsomal IP3 5-phosphatase hydrolyzed IP3 to myo-inositol 1,4-bisphosphate with an apparent Km of 28 microM and Vmax of 32 nmol/min per mg protein. The IP1 monophosphatase in the soluble fraction hydrolyzed IP1 into free inositol with an apparent Km of 89 microM and Vmax of 7 nmol/min per mg protein. (2) IP3 5-phosphatase and IP1 monophosphatase had optimal pH values at 8.0 and 7.0, respectively. (3) Both enzymes required Mg2+ and their highest specific activities were at a cation concentration of 2 mM. (4) Ca2+ (> 0.5 microM) exerted an inhibitory effect on IP3 5-phosphatase activity, and marked inhibition (47%) was observed at a concentration of 10 microM. Higher concentrations of the cation (> 100 microM) were required to inhibit IP1 monophosphatase. (5) IP1 monophosphatase, but not IP3 5-phosphatase, was inhibited by Li+. Li+ had no effect on the contractile response in this smooth muscle. (6) Both enzymes were inhibited by ATP and by the thiol-blocking agent, disulfiram. In addition, thimerosal, a thiol reagent, also inhibited the IP3 5-phosphatase activity. (7) Protein phosphorylation of the microsomal and soluble fractions with PKA or PKC had no effect on the activities of these enzymes. (8) Okadaic acid, a protein phosphatase inhibitor, had no effect on the activity of IP3 5-phosphatase. However, in the intact iris sphincter the toxin significantly reduced the carbachol-induced IP3 production, 1,2-diacylglycerol formation, measured as phosphatidic acid, and caused muscle relaxation.

  6. Rapid and reliable quantitation of amino acids and myo-inositol in mouse brain by high performance liquid chromatography and tandem mass spectrometry.

    PubMed

    Bathena, Sai P; Huang, Jiangeng; Epstein, Adrian A; Gendelman, Howard E; Boska, Michael D; Alnouti, Yazen

    2012-04-15

    Amino acids and myo-inositol have long been proposed as putative biomarkers for neurodegenerative diseases. Accurate measures and stability have precluded their selective use. To this end, a sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method based on multiple reaction monitoring was developed to simultaneously quantify glutamine, glutamate, γ-aminobutyric acid (GABA), aspartic acid, N-acetyl aspartic acid, taurine, choline, creatine, phosphocholine and myo-inositol in mouse brain by methanol extractions. Chromatography was performed using a hydrophilic interaction chromatography silica column within in a total run time of 15 min. The validated method is selective, sensitive, accurate, and precise. The method has a limit of quantification ranging from 2.5 to 20 ng/ml for a range of analytes and a dynamic range from 2.5-20 to 500-4000 ng/ml. This LC-MS/MS method was validated for biomarker discovery in models of human neurological disorders.

  7. Stereo- and regiospecificity of yeast phytases-chemical synthesis and enzymatic conversion of the substrate analogues neo- and L-chiro-inositol hexakisphosphate.

    PubMed

    Adelt, Stephan; Podeschwa, Michael; Dallmann, Guido; Altenbach, Hans-Josef; Vogel, Günter

    2003-02-01

    Phytases are enzymes that catalyze the hydrolysis of phosphate esters in myo-inositol hexakisphosphate (phytic acid). The precise routes of enzymatic dephosphorylation by phytases of the yeast strains Saccharomyces cerevisiae and Pichia rhodanensis have been investigated up to the myo-inositol trisphosphate level, including the absolute configuration of the intermediates. Stereoselective assignment of the myo-inositol pentakisphosphates (D-myo-inositol 1,2,4,5,6-pentakisphosphate and D-myo-inositol 1,2,3,4,5-pentakisphosphate) generated was accomplished by a new method based on enantiospecific enzymatic conversion and HPLC analysis. Via conduritol B or E derivatives the total syntheses of two epimers of myo-inositol hexakisphosphate, neo-inositol hexakisphosphate and L-chiro-inositol hexakisphosphate were performed to examine the specificity of the yeast phytases with these substrate analogues. A comparison of kinetic data and the degradation pathways determined gave the first hints about the molecular recognition of inositol hexakisphosphates by the enzymes. Exploitation of the high stereo- and regiospecificity observed in the dephosphorylation of neo- and L-chiro-inositol hexakisphosphate made it possible to establish enzyme-assisted steps for the synthesis of D-neo-inositol 1,2,5,6-tetrakisphosphate, L-chiro-inositol 1,2,3,5,6-pentakisphosphate and L-chiro-inositol 1,2,3,6-tetrakisphosphate.

  8. Speciation analysis of orthophosphate and myo-inositol hexakisphosphate in soil- and plant-related samples by high-performance ion chromatography combined with inductively coupled plasma mass spectrometry.

    PubMed

    Rugova, Ariana; Puschenreiter, Markus; Santner, Jakob; Fischer, Lisa; Neubauer, Stefan; Koellensperger, Gunda; Hann, Stephan

    2014-07-01

    A novel method based on high-performance ion chromatography inductively coupled plasma mass spectrometry employing strong anion exchange chromatography with HNO3 gradient elution for simultaneous analysis of orthophosphate and myo-inositol hexakisphosphate (IP6 ) in soil solution and plant extracts is presented. As inductively coupled plasma mass spectrometry analysis of phosphorus at m/z 31 is hampered by N-based interferences, (31)P was measured as (31)P(16)O(+) at m/z 47 employing dynamic reaction cell technique with O2 as reaction gas. Orthophosphate and IP6 were separated within a total chromatographic run-time of 12 min revealing a limit of detection of 0.3 μmol/L. The coefficients of determination obtained in a working range of 1-100 and 1-30 μmol/L were 0.9991 for orthophosphate and 0.9968 for IP6, respectively. The method was successfully applied to extracts from three different soils as well as root and shoot extracts of Brassica napus L. The precision of three independently prepared soil extracts was in the range of 4-10% relative standard deviation for PO4 (3-) and 3-8% relative standard deviation for IP6. Soil adsorption/desorption kinetics for IP6/orthophosphate were performed for investigating the sorption behavior of the two P species in the experimental soils.

  9. Inframolecular acid base studies of the tris and tetrakis myo-inositol phosphates including the 1,2,3-trisphosphate motif

    NASA Astrophysics Data System (ADS)

    Dozol, Hélène; Blum-Held, Corinne; Guédat, Philippe; Maechling, Clarisse; Lanners, Steve; Schlewer, Gilbert; Spiess, Bernard

    2002-12-01

    The intrinsic acid-base properties of the phosphate groups of three myo-inositol derivatives which display the 1,2,3-trisphosphate motif, i.e. (±)- myo-inositol 1,2,3-trisphosphate (Ins(1,2,3)P 3), (±)- myo-inositol 1,2,3,6-tetrakisphosphate (Ins(1,2,3,6)P 4), and (±)- myo-inositol 1,2,3,5-tetrakisphosphate (Ins(1,2,3,5)P 4) are reported. The studies were performed in 0.2 M KCl solution at 37 °C, near physiological ionic strength and temperature. In addition, in order to shed light on the transition metal complexation properties of Ins(1,2,3)P 3, the influence of the Zn 2+ cations on its 31P NMR titration curves was investigated. From the titration curves as well as from the determined protonation microconstants, it appears that for Ins(1,2,3)P 3, the two lateral P1 and P3 phosphates strongly contribute to stabilise a proton on the central P2 phosphate. However, in the fully deprotonated form of Ins(1,2,3)P 3, P1 and P3 repulse each other so that they establish hydrogen bonds with, respectively, their neighbouring OH6 and OH4 hydroxyls. The 1,2,3-trisphosphate motif of Ins(1,2,3,5)P 4 behaves very similarly to that of Ins(1,2,3)P 3 indicating a poor interaction with the distant P5 phosphate. By contrast, moving a phosphate group from position 5 to position 6 on the myo-inositol ring as in Ins(1,2,3,6)P 4, leads to major changes in the basicity and cooperativity of the phosphate groups. Finally, the presence of Zn 2+ cations has a marked influence on the 31P NMR titration curves of Ins(1,2,3)P 3, leading to the conclusion that two equatorial phosphates, assisted by a middle axial one, afford an optimal chelating moiety that is able to occupy all sites of the metal coordination polyhedron which could be the reason for its antioxidant properties.

  10. Analysis of free and total myo-inositol in foods, feeds, and infant formula by high-performance anion exchange chromatography with pulsed amperometric detection, including a novel total extraction using microwave-assisted acid hydrolysis and enzymatic treatment.

    PubMed

    Ellingson, David; Pritchard, Ted; Foy, Pamela; King, Kathryn; Mitchell, Barbara; Austad, John; Winters, Doug; Sullivan, Darryl

    2012-01-01

    A method for the analysis of free and total myo-inositol in foods, feeds, and infant formulas has been developed and validated using high-performance anion exchange chromatography with pulsed amperometric detection. The option of a free myo-inositol determination or a complete total myo-inositol determination from main bound sources can be achieved. These sources include phytates, lower'phosphorylated forms, and phosphatidylinositol. This approach gives the option for subtraction of myo-inositol from nonbioavailable sources when it is quantified using other methods if a total bioavailable myo-inositol result is desired for nutritional labeling of a product. The free analysis was validated in a milk-based infant formula, giving RSD(R) of 2.29% and RSD, of 2.06%. A mean recovery of 97.9% was achieved from various spike levels of myo-inositol. Certified National Institute of Standards and Technology reference material verified the method's compatibility and specificity. Two different total analyses were validated in a soy-based infant formula and compared. One technique involved using a conventional acid hydrolysis with autoclave incubation for 6 h, while the other used a novel technique of microwave-assisted acid hydrolysis with enzymatic treatment that can minimize extraction to 1 day. The autoclave analysis had RSD(R) of 2.08% and RSDr of 1.55%, along with a mean spike recovery of 102.1% at various myo-inositol spike levels. The microwave/enzyme total analysis had RSD(R) of 4.34% and RSD, of 4.70%, along with a mean spike recovery of 104.2% at various spike levels of myo-inositol. Main sources of myo-inositol including phytic acid and phosphatidylinositol were tested with both total analyses. Mean recoveries of phytic acid and phosphatidylinositol through the autoclave total analysis were 90.4 and 98.3%, respectively. Mean spike recoveries for these same sources in soy- based infant formula through the microwave/enzyme total analysis were 97.2 and 96

  11. Synthesis of myo-inositol 1,2,3-tris- and 1,2,3,5-tetrakis(dihydrogen phosphate)s as a tool for the inhibition of iron-gall-ink corrosion.

    PubMed

    Sala, Martin; Kolar, Jana; Strlic, Matija; Kocevar, Marijan

    2006-05-22

    Two myo-inositol phosphates, myo-inositol 1,2,3-tris(dihydrogen phosphate) and myo-inositol 1,2,3,5-tetrakis(dihydrogen phosphate), have been synthesised in several steps from myo-inositol (in Chem. Abstr.: d-myo-inositol) in the form of their sodium salts. They were shown to prevent iron-gall-ink decay in cellulose items at the same level as phytic acid dodecasodium salt.

  12. Enigmatic ion-exchange behavior of myo-inositol phosphates.

    PubMed

    Shelor, C Phillip; Liao, Hongzhu; Kadjo, Akinde Florence; Dasgupta, Purnendu K

    2015-05-05

    The separation of myo-inositol mono-, di-, tri-, tetra-, pentakis-, and hexakisphosphate (InsP1, InsP2, InsP3, InsP4, InsP5, InsP6) was carried out using hydroxide eluent ion chromatography. Acid hydrolysis of InsP6 (phytate) was used to prepare a distribution of InsPs, ranging from InsP1 to InsP5's and including unhydrolyzed InsP6. Counting all possible positional isomers (many of which have stereoisomers that will not be separable by conventional ion exchange), 40 chromatographically separable peaks are possible; up to 22 were separated and identified by mass spectrometry. InsPs show unusual ion-exchange behavior in two respects: (a) the retention order is not monotonically related with the charge on the ion and (b) at the same hydroxide eluent concentration, retention is greatly dependent on the eluent metal cation. The retention of InsP3-InsP6 was determined to be controlled by steric factors while elution was influenced by eluent cation complexation. These highly phosphorylated InsPs have a much greater affinity for alkali metals (Li(+) > Na(+) > K(+)) than quaternary ammonium ions. This difference in cation affinity was exploited to improve separation through the use of a tetramethylammonium hydroxide-sodium hydroxide gradient.

  13. myo-Inositol phosphate isomers generated by the action of a phytate-degrading enzyme from Klebsiella terrigena on phytate.

    PubMed

    Greiner, Ralf; Carlsson, Nils-Gunnar

    2006-08-01

    For the first time a dual pathway for dephosphorylation of myo-inositol hexakisphosphate by a histidine acid phytase was established. The phytate-degrading enzyme of Klebsiella terrigena degrades myo-inositol hexakisphosphate by stepwise dephosphorylation, preferably via D-Ins(1,2,4,5,6)P5, D-Ins(1,2,5,6)P4, D-Ins(1,2,6)P3, D-Ins(1,2)P2 and alternatively via D-Ins(1,2,4,5,6)P5, Ins(2,4,5,6)P4, D-Ins(2,4,5)P3, D-Ins(2,4)P2 to finally Ins(2)P. It was estimated that more than 98% of phytate hydrolysis occurs via D-Ins(1,2,4,5,6)P5. Therefore, the phytate-degrading enzyme from K. terrigena has to be considered a 3-phytase (EC 3.1.3.8). A second dual pathway of minor importance could be proposed that is in accordance with the results obtained by analysis of the dephosphorylation products formed by the action of the phytate-degrading enzyme of K. terrigena on myo-inositol hexakisphosphate. It proceeds preferably via D-Ins(1,2,3,5,6)P5, D-Ins(1,2,3,6)P4, Ins(1,2,3)P3, D-Ins(2,3)P2 and alternatively via D-Ins(1,2,3,5,6)P5, D-Ins(2,3,5,6)P4, D-Ins(2,3,5)P3, D-Ins(2,3)P2 to finally Ins(2)P. D-Ins(2,3,5,6)P4, D-Ins(2,3,5)P3, and D-Ins(2,4)P2 were reported for the first time as intermediates of enzymatic phytate dephosphorylation. A role of the phytate-degrading enzyme from K. terrigena in phytate breakdown could not be ruled out. Because of its cytoplasmatic localization and the suggestions for substrate recognition, D-Ins(1,3,4,5,6)P5 might be the natural substrate of this enzyme and, therefore, may play a role in microbial pathogenesis or cellular myo-inositol phosphate metabolism.

  14. Transport and metabolism of indole-3-acetyl-myo-inositol-galactoside in seedlings of Zea mays

    NASA Technical Reports Server (NTRS)

    Komoszynski, M.; Bandurski, R. S.

    1986-01-01

    Indole-3-acetyl-myo-inositol galactoside labeled with 3H in the indole and 14C in the galactose moieties was applied to kernels of 5 day old germinating seedlings of Zea mays. Indole-3-acetyl-myo-inositol galactoside was not transported into either the shoot or root tissue as the intact molecule but was instead hydrolyzed to yield [3H]indole-3-acetyl-myo-inositol and [3H]indole-3-acetic acid which were then transported to the shoot with little radioactivity going to the root. With certain assumption concerning the equilibration of applied [3H]indole-3-acetyl-myo-inositol-[U-14C]galactose with the endogenous pool, it may be concluded that indole-3-acetyl-myo-inositol galactoside in the endosperm supplies about 2 picomoles per plant per hour of indole-3-acetyl-myo-inositol and 1 picomole per plant per hour of indole-3-acetic acid to the shoot and thus is comparable to indole-3-acetyl-myo-inositol as a source of indole-acetic acid for the shoot. Quantitative estimates of the amount of galactose in the kernels suggest that [3H]indole-3-acetyl-myo-inositol-[14C]galactose is hydrolyzed after the compound leaves the endosperm but before it reaches the shoot. In addition, [3H]indole-3-acetyl-myo-inositol-[14C]galactose supplies appreciable amounts of 14C to the shoot and both 14C and 3H to an uncharacterized insoluble fraction of the endosperm.

  15. Generation of stable 'low phytic acid' transgenic rice through antisense repression of the 1D-myo-inositol 3-phosphate synthase gene (RINO1) using the 18-kDa oleosin promoter.

    PubMed

    Kuwano, Mio; Mimura, Tetsuro; Takaiwa, Fumio; Yoshida, Kaoru T

    2009-01-01

    Phytic acid acts as the major storage form of phosphorus in plant seeds and is poorly digested by monogastric animals. The degradation of phytic acid in animal diets is necessary to overcome both environmental and nutritional issues. The enzyme 1D-myo-inositol 3-phosphate [Ins(3)P(1)] synthase (EC 5.5.1.4) catalyses the first step of myo-inositol biosynthesis and directs phytic acid biosynthesis in seeds. The rice Ins(3)P(1) synthase gene (RINO1) is highly expressed in developing seed embryos and in the aleurone layer, where phytic acid is synthesized and stored. In rice seeds, 18-kDa oleosin (Ole18) is expressed in a seed-specific manner, and its transcripts are restricted to the embryo and the aleurone layer. Therefore, to effectively suppress phytic acid biosynthesis, antisense RINO1 cDNA was expressed under the control of the Ole18 promoter, directing the same spatial pattern in seeds as RINO1 in transgenic rice plants. The generated transgenic rice plants showed strong 'low phytic acid' (lpa) phenotypes, in which seed phytic acid was reduced by 68% and free available phosphate was concomitantly increased. No negative effects on seed weight, germination or plant growth were observed. The available phosphate levels of the stable transgenic plants surpassed those of currently available rice lpa mutants.

  16. Enzymic synthesis of 1-O-indol-3-ylacetyl-beta-D-glucose and indol-3-ylacetyl-myo-inositol.

    PubMed Central

    Michalczuk, L; Bandurski, R S

    1982-01-01

    An enzyme fraction from extracts of immature kernels of Zea mays catalyses the formation of 1-O-indol-3-ylacetyl-beta-D-glucose from indol-3-ylacetic acid and UDP-glucose. A second enzyme fraction catalyses the formation of indol-3-ylacetyl-myo-inositol from 1-O-indol-3-ylacetyl-beta-D-glucose and myo-inositol. To our knowledge, this is the first example of hydroxy-group acylation by a 1-O-acyl sugar. The following reaction sequence is proposed: Indol-3-ylacetic acid + UDP-glucose leads to indol-3-ylacetylglucose + UDP (1) Indol-3-ylacetylglucose + myo-inositol leads to indol-3-ylacetyl-myo-inositol + glucose (2) The enzyme catalysing reaction (1) is called UDP-glucose:indol-3-ylacetate glucosyl-transferase (indol-3-ylacetylglucose synthase), and that catalysing reaction (2) is indol-3-ylacetylglucose:myo-inositol indol-3-ylacetyltransferase (indol-3-ylacetyl-myo-inositol synthase). We further show that indol-3-ylacetylglucose synthase is specific for UDP-glucose and, at the stage of purity tested, the enzyme will use either indol-3-ylacetic acid or naphthalene-1-acetic acid, but not 2.4-dichlorophenoxyacetic acid, as glucose acceptor. The indol-3-ylacetyl-myo-inositol synthase is specific for indol-3-ylacetyl-glucose and will not use naphthalene-1-acetylglucose as substrate, and it is specific for myo-inositol among the alcohol acceptors tested. Thus, of the auxins tested, only indol-3-ylacetic acid forms the myo-inositol ester. PMID:6218801

  17. Myo-Inositol content determined by myo-inositol biosynthesis and oxidation in blueberry fruit.

    PubMed

    Song, Fangyuan; Su, Hongyan; Yang, Nan; Zhu, Luying; Cheng, Jieshan; Wang, Lei; Cheng, Xianhao

    2016-11-01

    Myo-inositol metabolism in plant edible organs has become the focus of many recent studies because of its benefits to human health and unique functions in plant development. In this study, myo-inositol contents were analyzed during the development of two blueberry cultivars, cv 'Berkeley' and cv 'Bluecrop'. Furthermore, two VcMIPS 1/2 (Vaccinium corymbosum MIPS) genes, one VcIMP (Vaccinium corymbosum IMP) gene and one VcMIOX (Vaccinium corymbosum MIOX) gene were isolated for the first time from blueberry. The expression patterns of VcMIPS2, VcIMP and VcMIOX genes showed a relationship with the change profiles of myo-inositol content during fruit ripening. The results were further confirmed by the analyses of the enzyme activity. Results indicated that both myo-inositol biosynthesis and oxidation played important roles in determining of myo-inositol levels during the development of blueberry. To our knowledge, this report is the first to discuss myo-inositol levels in fruits in terms of biosynthesis and catabolism.

  18. Asymmetric distribution of glucose and indole-3-acetyl-myo-inositol in geostimulated Zea mays seedlings

    NASA Technical Reports Server (NTRS)

    Momonoki, Y. S.; Bandurski, R. S. (Principal Investigator)

    1988-01-01

    Indole-3-acetyl-myo-inositol occurs in both the kernel and vegetative shoot of germinating Zea mays seedlings. The effect of a gravitational stimulus on the transport of [3H]-5-indole-3-acetyl-myo-inositol and [U-14C]-D-glucose from the kernel to the seedling shoot was studied. Both labeled glucose and labeled indole-3-acetyl-myo-inositol become asymmetrically distributed in the mesocotyl cortex of the shoot with more radioactivity occurring in the bottom half of a horizontally placed seedling. Asymmetric distribution of [3H]indole-3-acetic acid, derived from the applied [3H]indole-3-acetyl-myo-inositol, occurred more rapidly than distribution of total 3H-radioactivity. These findings demonstrate that the gravitational stimulus can induce an asymmetric distribution of substances being transported from kernel to shoot. They also indicate that, in addition to the transport asymmetry, gravity affects the steady state amount of indole-3-acetic acid derived from indole-3-acetyl-myo-inositol.

  19. An accelerated mass spectrometric method for measuring myo-inositol in phosphatidylinositol in rat brain

    NASA Astrophysics Data System (ADS)

    Deutsch, Joseph; Ma, Kaizung; Rapoport, Stanley I.

    2006-03-01

    A fast and efficient chemical ionization mass spectrometric (CI-GC-MS) method for measuring myo-inositol in phosphatidylinositol (PtdIns) in rat brain has been developed. Previously, quantitation of PtdIns involved the release of the myo-inositol by two enzymatic reactions using phospholipase C and alkaline phosphatase. The hydrolytic action of these enzymes was replaced by using commercially available 48% hydrofluoric acid (HF) at 80 °C for 30 min. The process can be carried out on the crude Folch extract of brain phospholipids without prior thin layer chromatography (TLC) purification, thereby significantly increasing the speed of analysis. For quantification, unlabeled myo-inositol, labeled myo- and neo-inositol (internal standard) were converted to acetate derivatives and analyzed by CI-GC-MS.

  20. Phytases Improve Myo-Inositol Bioaccessibility in Rye Bread: A Study Using an In Vitro Method of Digestion and a Caco-2 Cell Culture Model.

    PubMed

    Duliński, Robert; Cielecka, Emilia Katarzyna; Pierzchalska, Małgorzata; Żyła, Krzysztof

    2015-03-01

    Preparations of 6-phytase A (EC 3.1.3.26) and phytase B (acid phosphatase, EC 3.1.3.2) were applied alone and combined in the preparation of dough to estimate their catalytic potential for myo-inositol liberation from rye flour in the breadmaking technology. The experimental bread samples were ground after baking and subjected to determination of myo-inositol bioavailability by an in vitro method that simulated digestion in a human alimentary tract, followed by measurements of myo-inositol transport through enterocyte- -like differentiated Caco-2 cells to determine its bioaccessibility. Myo-inositol content was measured by a high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) technique. The concentration of myo-inositol in the dialysates of control bread was 25.3 µg/mL, whereas in the dialysates of bread sample baked with 6-phytase A, the concentration increased to 35.4 µg/mL, and in the bread baked with phytase B to 64.98 µg/mL. Simultaneous application of both enzymes resulted in myo-inositol release of 64.04 µg/mL. The highest bioaccessibility of myo-inositol, assessed by the measurement of the passage through the Caco-2 monolayer was determined in the bread baked with the addition of 6-phytase A. Enzymatically modified rye bread, particularly by the addition of 6-phytase A, may be therefore a rich source of a highly bioaccessible myo- -inositol.

  1. myo-Inositol synthesis from (1-/sup 3/H)glucose in Phaseolus vulgaris L. during early stages of germination

    SciTech Connect

    Sasaki, K.; Taylor, I.E.P.

    1986-06-01

    Radiolabeled D-(1-/sup 3/H)glucose was fed by imbibition under sterile conditions to bean (Phaseolus vulgaris L.) seeds. After 72 and 96 hours of feeding, the /sup 3/H was located in uronic acid and pentose residues as well as hexose residues of cell wall polysaccharides in growing hypocotyl and root. Free myo-inositol present in cotyledons, hypocotyl, and root also contained /sup 3/H, showing that de novo synthesis of myo-inositol from (1-/sup 3/H)glucose did occur during the first 72 hours of germination. More than 90% of the labeled, free myo-inositol was present in the cotyledons. The /sup 3/H percentage in trifluoroacetic acid-soluble arabinaose residues of cell wall polysaccharides from 72-hour-old bean hypocotyls was only half of their mole percentage. On the other hand, /sup 3/H percentages in hexose residues were higher than their mole percentages. The results suggest that myo-inositol is synthesized from reserve sugars during the very early stages of germination, and that the newly synthesized myo-inositol, as well as that stored in cotyledons, can be used for the construction of new hypocotyl and root cell wall polysaccharides after conversion into uronic acids and pentoses via the myo-inositol oxidation pathway.

  2. myo-inositol phosphate isomers generated by the action of a phytase from a malaysian waste-water bacterium.

    PubMed

    Greiner, Ralf; Farouk, Abd-Elaziem; Carlsson, Nils-Gunnar; Konietzny, Ursula

    2007-12-01

    Using a combination of High-Performance Ion Chromatography analysis and kinetic studies, the pathway of myo-inositol hexakisphosphate dephosphorylation by a phytase from a Malaysian waste-water bacterium was established. The data demonstrate that the phytase preferably dephosphorylates myo-inositol hexakisphosphate in a stereospecific way by sequential removal of phosphate groups via D-I(1,2,3,4,5)P(5), D-I(2,3,4,5)P(4), D-I(2,3,4)P(3), D-I(2,3)P(2) to finally I(2)P. It was estimated that more than 90% of phytate hydrolysis occurs via D-I(1,2,3,4,5)P(5). Thus, the phytase from the Malaysian waste-water bacterium has to be considered a 6-phytase (E.C. 3.1.3.26). A second pathway of minor importance could be proposed which is in accordance with the results obtained from analysis of the dephosphorylation products formed by the action of the phytase under investigation on myo-inositol hexakisphosphate. It proceeds via D/L-I(1,2,4,5,6)P(5), D/L-I(1,2,4,5)P(4), D/L-I(1,2,4)P(3), D/L-I(2,4)P(2) to finally I(2)P.

  3. Determination of myo-inositol (free and bound as phosphatidylinositol) in infant formula and adult nutritionals by liquid chromatography/pulsed amperometry with column switching: first action 2011.18.

    PubMed

    Schimpf, Karen; Thompson, Linda; Baugh, Steve

    2012-01-01

    Myo-inositol is a 6-carbon cyclic polyalcohol also known as meso-inositol, meat sugar, inosite, and i-inositol. It occurs in nature in both free (myo-inositol) and bound (inositol phosphates and phosphatidylinositol) forms. For the determination of free myo-inositol, samples are mixed with dilute hydrochloric acid to extract myo-inositol and precipitate proteins, diluted with water, and filtered. For the determination of myo-inositol bound as phosphatidylinositol, samples are extracted with chloroform, isolated from other fats with silica SPE cartridges, and hydrolyzed with concentrated acid to free myo-inositol. Prepared samples are first injected onto a Dionex CarboPac PA1 column, which separates myo-inositol from other late-eluting carbohydrates. After column switching, myo-inositol is further separated on a CarboPac MA1 column using a 0.12% sodium hydroxide mobile phase; strongly retained carbohydrates are eluted from the PA1 column with a 3% sodium hydroxide mobile phase. Eluant from the CarboPac MA1 analytical column passes through an electrochemical detector cell where myo-inositol is detected by pulsed amperometry using a gold electrode. The method showed appropriate performance characteristics versus selected established standard method performance requirement parameters for the determination of myo-inositol: linear response; repeatability (RSDr) of 2%; and intermediate precision (RSDir) of 2.5%. Instrument LOD and LOQ were 0.0004 and 0.0013 mg/100 mL, respectively, and correspond to a free myo-inositol quantitation limit of 0.026 mg/100 g and a phosphatidylinositol quantitation limit of 0.016 mg/100 g. Correlation with the reference microbiological assay was good. The proposed method has been accepted by the Expert Review Panel as an AOAC First Action Method, suitable for the routine determination of myo-inositol in infant formula and adult nutritionals.

  4. Characterization of two genes, Impa1 and Impa2 encoding mouse myo-inositol monophosphatases.

    PubMed

    Shamir, A; Sjøholt, G; Ebstein, R P; Agam, G; Steen, V M

    2001-06-27

    The enzyme myo-inositol monophosphatase (Impa) catalyzes the synthesis of free myo-inositol from various myo-inositol monophosphates in the phosphatidylinositol signaling system. Impa is a lithium-blockable enzyme that has been hypothesized to be the biological target for lithium-salts used as mood-stabilizing drugs in the treatment of manic-depressive (bipolar) illness. As an initial step to explore the functional consequences of reduced or absent Impa activity in an animal model we here report the isolation of two Impa-encoding mouse genes, Impa1 and Impa2. Impa1 spans approximately 17.5 kb and contains nine exons of 46--1354 bp encoding a protein of 277 amino acids. Impa2 spans at least 19.5 kb and contains eight exons of 46--444 bp size encoding a protein of 290 amino acids. The genomic structure including the positions of the exon-intron splice sites seems to be conserved among myo-inositol monophosphatase genes in mammalian species. One or more Impa-like genes do also exist in evolutionary more distant species like invertebrates, plants and bacteria. The proteins encoded by the non-vertebrate genes seem to be equally related to Impa1 and Impa2. We therefore suggest that the Impa1 and Impa2 genes duplicated from a common ancestral gene after the evolutionary divergence of vertebrates.

  5. Regioselective Opening of myo-Inositol Orthoesters: Mechanism and Synthetic Utility

    PubMed Central

    2013-01-01

    Acid hydrolysis of myo-inositol 1,3,5-orthoesters, apart from orthoformates, exclusively affords the corresponding 2-O-acyl myo-inositol products via a 1,2-bridged five-membered ring dioxolanylium ion intermediate observed by NMR spectroscopy. These C-2-substituted inositol derivatives provide valuable precursors for rapid and highly efficient routes to 2-O-acyl inositol 1,3,4,5,6-pentakisphosphates and myo-inositol 1,3,4,5,6-pentakisphosphate with biologically interesting and anticancer properties. Deuterium incorporation into the α-methylene group of such alkyl ester products (2-O-C(O)CD2R), when the analogous alkyl orthoester is treated with deuterated acid, is established utilizing the novel orthoester myo-inositol 1,3,5-orthobutyrate as an example. Such deuterated ester products provide intermediates for deuterium-labeled synthetic analogues. Investigation into this selective formation of 2-O-ester products and the deuterium incorporation is presented with proposed mechanisms from NMR experiments. PMID:23438216

  6. Identification of novel rice low phytic acid mutations via TILLING by sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate or InsP6) accounts for 75-85% of the total phosphorus in seeds. Low phytic acid (lpa) mutants exhibit decreases in seed InsP6 with corresponding increases in inorganic P which, unlike phytic acid P, is readily utilized by humans and monogastric ...

  7. myo-Inositol and Phytate Are Toxic to Formosan Subterranean Termites (Isoptera: Rhinotermitidae).

    PubMed

    Veillon, Lucas; Bourgeois, Jared; Leblanc, Amanda; Henderson, Gregg; Marx, Brian D; Muniruzzaman, Syed; Laine, Roger A

    2014-10-01

    Several rare and common monosaccharides were screened for toxic effects on the Formosan subterranean termite, Coptotermes formosanus Shiraki, with the aim of identifying environmentally friendly termiticides. myo-Inositol and phytic acid, which are nontoxic to mammals, were identified as potential termite control compounds. Feeding bioassays with termite workers, where both compounds were supplied on filter paper in concentrations from 160.2 to 1,281.7 μg/mm(3), showed concentration-dependent toxicity within 2 wk. Interestingly myo-inositol was nontoxic when administered to termites in agar (40 mg/ml) in the absence of a cellulosic food source, an unexplained phenomenon. In addition, decreased populations of termite hindgut protozoa were observed upon feeding on myo-inositol but not phytate-spiked filter paper. Radiotracer feeding studies using myo-inositol-[2-(3)H] with worker termites showed no metabolism after ingestion over a 2-d feeding period, ruling out metabolites responsible for the selective toxicity.

  8. The Low Phytic Acid Phenotype in Soybean Line CX1834 is Due to Mutations in Two Homologues of the Maize Low Phytic Acid Gene

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant seeds accumulate phosphorus in the form of myo-inositol-1,2,3,4,5,6 hexa-kisphosphate, commonly referred to as phytic acid. Phytic acid is found complexed with cationic mineral species in the form of phytate, which is not well digested or absorbed by monogastric species such as humans, poultry...

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

    NASA Technical Reports Server (NTRS)

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

    1986-01-01

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

  10. Identification of the Molecular Basis of the Seed Low Phytic Acid Phenotype in Soybean Line CX1834

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant seeds accumulate phosphorus in the form of myo-inositol-1,2,3,4,5,6 hexakisphosphate, commonly referred to as phytic acid. Phytic acid is complexed with cationic mineral species in the form of phytate, which is not well digested or absorbed by monogastric species such as humans, poultry and sw...

  11. Identification of the Molecular Basis of the Seed Low Phytic Acid Phenotype in Soybean Line CX1834

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant seeds accumulate phosphorus in the form of myo-inositol-1,2,3,4,5,6 hexakisphosphate, commonly referred to as phytic acid. Phytic acid is complexed with cationic mineral species in the form of phytate, which is not well digested or absorbed by monogastric species such as humans, poultry and s...

  12. Myo-Inositol-Dependent Sodium Uptake in Ice Plant1

    PubMed Central

    Nelson, Donald E.; Koukoumanos, Michelle; Bohnert, Hans J.

    1999-01-01

    In salt-stressed ice plants (Mesembryanthemum crystallinum), sodium accumulates to high concentrations in vacuoles, and polyols (myo-inositol, d-ononitol, and d-pinitol) accumulate in the cytosol. Polyol synthesis is regulated by NaCl and involves induction and repression of gene expression (D.E. Nelson, B. Shen, and H.J. Bohnert [1998] Plant Cell 10: 753–764). In the study reported here we found increased phloem transport of myo-inositol and reciprocal increased transport of sodium and inositol to leaves under stress. To determine the relationship between increased translocation and sodium uptake, we analyzed the effects of exogenous application of myo-inositol: The NaCl-inducible ice plant myo-inositol 1-phosphate synthase is repressed in roots, and sodium uptake from root to shoot increases without stimulating growth. Sodium uptake and transport through the xylem was coupled to a 10-fold increase of myo-inositol and ononitol in the xylem. Seedlings of the ice plant are not salt-tolerant, and yet the addition of exogenous myo-inositol conferred upon them patterns of gene expression and polyol accumulation observed in mature, salt-tolerant plants. Sodium uptake and transport through the xylem was enhanced in the presence of myo-inositol. The results indicate an interdependence of sodium uptake and alterations in the distribution of myo-inositol. We hypothesize that myo-inositol could serve not only as a substrate for the production of compatible solutes but also as a leaf-to-root signal that promotes sodium uptake. PMID:9880357

  13. Inframolecular acid-base and coordination properties towards Na(+) and Mg(2+) of myo-inositol 1,3,4,5,6-pentakisphosphate: a structural approach to biologically relevant species.

    PubMed

    Veiga, Nicolás; Torres, Julia; Macho, Israel; Gómez, Kerman; Godage, Himali Y; Riley, Andrew M; Potter, Barry V L; González, Gabriel; Kremer, Carlos

    2013-05-07

    The myo-inositol phosphates (InsPs) are specific signalling metabolites ubiquitous in eukaryotic cells. Although Ins(1,3,4,5,6)P(5) is the second most abundant member of the InsPs family, its certain biological roles are far from being elucidated, in part due to the large number of species formed by Ins(1,3,4,5,6)P(5) in the presence of metal ions. In light of this, we have strived in the past to make a complete and at the same time "biological-user-friendly" description of the Ins(1,3,4,5,6)P(5) chemistry with mono and multivalent cations. In this work we expand these studies focusing on the inframolecular aspects of its protonation equilibria and the microscopic details of its coordination behaviour towards biologically relevant metal ions. We present here a systematic study of the Ins(1,3,4,5,6)P(5) intrinsic acid-base processes, in a non-interacting medium, and over a wide pH range, analyzing the (31)P NMR curves by means of a model based on the Cluster Expansion Method. In addition, we have used a computational approach to analyse the energetic and structural features of the protonation and conformational changes of Ins(1,3,4,5,6)P(5), and how they are influenced by the presence of two physiologically relevant cations, Na(+) and Mg(2+).

  14. 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.

  15. Phytases Improve Myo-Inositol Bioaccessibility in Rye Bread: A Study Using an In Vitro Method of Digestion and a Caco-2 Cell Culture Model

    PubMed Central

    Cielecka, Emilia Katarzyna; Pierzchalska, Małgorzata; Żyła, Krzysztof

    2015-01-01

    Summary Preparations of 6-phytase A (EC 3.1.3.26) and phytase B (acid phosphatase, EC 3.1.3.2) were applied alone and combined in the preparation of dough to estimate their catalytic potential for myo-inositol liberation from rye flour in the breadmaking technology. The experimental bread samples were ground after baking and subjected to determination of myo-inositol bioavailability by an in vitro method that simulated digestion in a human alimentary tract, followed by measurements of myo-inositol transport through enterocyte- -like differentiated Caco-2 cells to determine its bioaccessibility. Myo-inositol content was measured by a high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) technique. The concentration of myo-inositol in the dialysates of control bread was 25.3 µg/mL, whereas in the dialysates of bread sample baked with 6-phytase A, the concentration increased to 35.4 µg/mL, and in the bread baked with phytase B to 64.98 µg/mL. Simultaneous application of both enzymes resulted in myo-inositol release of 64.04 µg/mL. The highest bioaccessibility of myo-inositol, assessed by the measurement of the passage through the Caco-2 monolayer was determined in the bread baked with the addition of 6-phytase A. Enzymatically modified rye bread, particularly by the addition of 6-phytase A, may be therefore a rich source of a highly bioaccessible myo- -inositol. PMID:27904333

  16. Probing the promiscuous active site of myo-inositol dehydrogenase using synthetic substrates, homology modeling, and active site modification.

    PubMed

    Daniellou, Richard; Zheng, Hongyan; Langill, David M; Sanders, David A R; Palmer, David R J

    2007-06-26

    The active site of myo-inositol dehydrogenase (IDH, EC 1.1.1.18) from Bacillus subtilis recognizes a variety of mono- and disaccharides, as well as 1l-4-O-substituted inositol derivatives. It catalyzes the NAD+-dependent oxidation of the axial alcohol of these substrates with comparable kinetic constants. We have found that 4-O-p-toluenesulfonyl-myo-inositol does not act as a substrate for IDH, in contrast to structurally similar compounds such as those bearing substituted benzyl substituents in the same position. X-ray crystallographic analysis of 4-O-p-toluenesulfonyl-myo-inositol and 4-O-(2-naphthyl)methyl-myo-inositol, which is a substrate for IDH, shows a distinct difference in the preferred conformation of the aryl substituent. Conformational analysis of known substrates of IDH suggests that this conformational difference may account for the difference in reactivity of 4-O-p-toluenesulfonyl-myo-inositol in the presence of IDH. A sequence alignment of IDH with the homologous glucose-fructose oxidoreductase allowed the construction of an homology model of inositol dehydrogenase, to which NADH and 4-O-benzyl-scyllo-inosose were docked and the active site energy minimized. The active site model is consistent with all experimental results and suggests that a conserved tyrosine-glycine-tyrosine motif forms the hydrophobic pocket adjoining the site of inositol recognition. Y233F and Y235F retain activity, while Y233R and Y235R do not. A histidine-aspartate pair, H176 and D172, are proposed to act as a dyad in which H176 is the active site acid/base. The enzyme is inactivated by diethyl pyrocarbonate, and the mutants H176A and D172N show a marked loss of activity. Kinetic isotope effect experiments with D172N indicate that chemistry is rate-determining for this mutant.

  17. Effects of glucose on sorbitol pathway activation, cellular redox, and metabolism of myo-inositol, phosphoinositide, and diacylglycerol in cultured human retinal pigment epithelial cells.

    PubMed Central

    Thomas, T P; Porcellati, F; Kato, K; Stevens, M J; Sherman, W R; Greene, D A

    1994-01-01

    Sorbitol (aldose reductase) pathway flux in diabetes perturbs intracellular metabolism by two putative mechanisms: reciprocal osmoregulatory depletion of other organic osmolytes e.g., myo-inositol, and alterations in NADPH/NADP+ and/or NADH/NAD+. The "osmolyte" and "redox" hypotheses predict secondary elevations in CDP-diglyceride, the rate-limiting precursor for phosphatidylinositol synthesis, but through different mechanisms: the "osmolyte" hypothesis via depletion of intracellular myo-inositol (the cosubstrate for phosphatidylinositol-synthase) and the "redox" hypothesis through enhanced de novo synthesis from triose phosphates. The osmolyte hypothesis predicts diminished phosphoinositide-derived arachidonyl-diacylglycerol, while the redox hypothesis predicts increased total diacylglycerol and phosphatidic acid. In high aldose reductase expressing retinal pigment epithelial cells, glucose-induced, aldose reductase inhibitor-sensitive CDP-diglyceride accumulation and inhibition of 32P-incorporation into phosphatidylinositol paralleled myo-inositol depletion (but not cytoplasmic redox, that was unaffected by glucose) and depletion of arachidonyl-diacylglycerol. 3 mM pyruvate added to the culture medium left cellular redox unaltered, but stimulated Na(+)-dependent myo-inositol uptake, accumulation, and incorporation into phosphatidylinositol. These results favor myo-inositol depletion rather than altered redox as the primary cause of glucose-induced aldose reductase-related defects in phospholipid metabolism in cultured retinal pigment epithelial cells. Images PMID:8201009

  18. The “Other” Inositols and Their Phosphates: Synthesis, Biology and Medicine (with Recent Advances in myo-Inositol Chemistry)

    PubMed Central

    Thomas, Mark P; Mills, Stephen J; Potter, Barry V L

    2016-01-01

    Cell signalling via inositol phosphates, eg the second messenger myo-inositol 1,4,5-trisphosphate, and phosphoinositides comprises a huge field of biology. Of nine 1,2,3,4,5,6-cyclohexanehexol isomers, myo-inositol is pre-eminent, with “other” inositols (cis-, epi-, allo-, muco-, neo-, l-chiro-, d-chiro- and scyllo-) and derivatives rarer or thought not to exist in nature. However, recently, neo- and d-chiro-inositol hexakisphosphates were revealed in both terrestrial and aquatic ecosystems, highlighting the paucity of knowledge of the origins and potential biological functions of such stereoisomers, a prevalent group of environmental organic phosphates, and their parent inositols. Some “other” inositols are medically relevant, e.g. scyllo-inositol (neurodegenerative diseases), and d-chiro-inositol (diabetes). It is timely to consider exploration of roles and applications of “other” isomers and their derivatives, likely by exploiting techniques now well developed for the myo-series. PMID:26694856

  19. Inositol-phosphodihydroceramides in the periodontal pathogen Tannerella forsythia: Structural analysis and incorporation of exogenous myo-inositol

    PubMed Central

    Megson, Zoë Anne; Pittenauer, Ernst; Duda, Katarzyna Anna; Engel, Regina; Ortmayr, Karin; Koellensperger, Gunda; Mach, Lukas; Allmaier, Günter; Holst, Otto; Messner, Paul; Schäffer, Christina

    2015-01-01

    Background Unique phosphodihydroceramides containing phosphoethanolamine and glycerol have been previously described in Porphyromonas gingivalis. Importantly, they were shown to possess pro-inflammatory properties. Other common human bacteria were screened for the presence of these lipids, and they were found, amongst others, in the oral pathogen Tannerella forsythia. To date, no detailed study into the lipids of this organism has been performed. Methods Lipids were extracted, separated and purified by HPTLC, and analyzed using GC-MS, ESI–MS and NMR. Of special interest was how T. forsythia acquires the metabolic precursors for the lipids studied here. This was assayed by radioactive and stable isotope incorporation using carbon-14 and deuterium labeled myo-inositol, added to the growth medium. Results T. forsythia synthesizes two phosphodihydroceramides (Tf GL1, Tf GL2) which are constituted by phospho-myo-inositol linked to either a 17-, 18-, or 19-carbon sphinganine, N-linked to either a branched 17:0(3-OH) or a linear 16:0(3-OH) fatty acid which, in Tf GL2, is, in turn, ester-substituted with a branched 15:0 fatty acid. T. forsythia lacks the enzymatic machinery required for myo-inositol synthesis but was found to internalize inositol from the medium for the synthesis of both Tf GL1 and Tf GL2. Conclusion The study describes two novel glycolipids in T. forsythia which could be essential in this organism. Their synthesis could be reliant on an external source of myo-inositol. General significance The effects of these unique lipids on the immune system and their role in bacterial virulence could be relevant in the search for new drug targets. PMID:26277409

  20. Myo-Inositol in the Treatment of Teenagers Affected by PCOS

    PubMed Central

    Barbakadze, Ludmila; Kvashilava, Nana

    2016-01-01

    Objective. To compare the effectiveness of myo-inositol (MI) and oral contraceptive pills (OCPs) in monotherapy and MI in combination with OCPs in the treatment of teenagers affected by polycystic ovary syndrome (PCOS). Methods. 61 adolescent girls aged 13–19 years, with PCOS, were involved in the prospective, open-label study. Patients were randomized into three groups: I group, 20 patients receiving drospirenone 3 mg/ethinyl estradiol 30 μg; II group, 20 patients receiving 4 g myo-inositol plus 400 mg folic acid; III group, 21 patients receiving both medications. Results. After receiving MI significant reduction in weight, BMI, glucose, C-peptide, insulin, HOMA-IR, FT, and LH was detected. The levels of SHBG, TT, FAI, DHEA-S, and AMH did not change statistically significantly. After receiving OCPs weight and BMI slightly increased, but metabolic parameters did not change. Combination of MI and OCPs did not change weight and BMI, but reduction in C-peptide, insulin, and HOMA-IR was detected. TT, FT, FAI, DHEA-S, LH, and AMH levels decreased and SHBG increased. Conclusions. Administration of MI is a safe and effective method to prevent and correct metabolic disorders in teenagers affected by PCOS. With combination of MI and OCPs antiandrogenic effects are enhanced, negative impact of OCPs on weight gain is balanced, and metabolic profile is improved. PMID:27635134

  1. Kinetic mechanism of the Zn-dependent aryl-phosphatase activity of myo-inositol-1-phosphatase.

    PubMed

    Caselli, Anna; Casolaro, Mario; Ranaldi, Francesco; Manao, Giampaolo; Camici, Guido; Giachetti, Eugenio

    2007-02-01

    Myo-inositol-1-phosphatase (EC 3.1.3.25) is able to hydrolyze myo-inositol-1-phosphate in the presence of Mg(2+) ions at neutral pH, and also p-nitrophenyl phosphate in the presence of Zn(2+)-ions at acidic pH. This enzyme plays a role in phosphatidylinositol cell signalling and is a putative target of lithium therapy in manic depression. We elucidate here the kinetic mechanism of the Zn-dependent activity of myo-inositol-1-phosphatase. As part of this analysis it was necessary to determine the basicity constants of p-nitrophenyl phosphate and the stability constant of its metal-complex in the presence of zinc chloride. We find that the Zn-dependent reaction may be described either by a rapid-equilibrium random mechanism or an ordered steady-state mechanism in which the substrate binds to the free enzyme prior to the metal ion. In both models the Zn-substrate complex acts as a high affinity inhibitor, yielding a dead-end species through its binding to the enzyme-Zn-substrate in rapid-equilibrium or to the enzyme-phosphate complexes in a steady-state model. Phosphate is a competitive inhibitor of the enzyme with respect to the substrate and an uncompetitive inhibitor with respect to zinc ions.

  2. Comparison between effects of myo-inositol and D-chiro-inositol on ovarian function and metabolic factors in women with PCOS.

    PubMed

    Pizzo, Alfonsa; Laganà, Antonio Simone; Barbaro, Luisa

    2014-03-01

    Myo-inositol and D-chiro-inositol are capable of improving the ovarian function and metabolism of polycystic ovary syndrome (PCOS) patients. The aim of this work is to compare the effects of myo-inositol and D-chiro-inositol in PCOS. We enrolled 50 patients, with homogeneous bio-physical features, affected by PCOS and menstrual irregularities, and we randomly divided them into two groups: 25 were treated with 4 g of myo-inositol/die plus 400 mcg of folic acid/die orally for six months, 25 with 1 g of D-chiro-inositol/die plus 400 mcg of folic acid/die orally for six months. We analyzed in both groups pre-treatment and post-treatment BMI, systolic and diastolic blood pressure, Ferriman-Gallwey score, Cremoncini score, serum LH, LH/FSH ratio, total and free testosterone, dehydroepiandrosterone sulfate (DHEA-S), Δ-4-androstenedione, SHBG, prolactin, glucose/immunoreactive insulin (IRI) ratio, homeostatic model assessment (HOMA) index, and the resumption of regular menstrual cycles. Both the isoforms of inositol were effective in improving ovarian function and metabolism in patients with PCOS, although myo-inositol showed the most marked effect on the metabolic profile, whereas D-chiro-inositol reduced hyperandrogenism better.

  3. Hydrogen peroxide and nitric oxide mediated cold- and dehydration-induced myo-inositol phosphate synthase that confers multiple resistances to abiotic stresses.

    PubMed

    Tan, Jiali; Wang, Congying; Xiang, Bin; Han, Ruihong; Guo, Zhenfei

    2013-02-01

    myo-Inositol phosphate synthase (MIPS) is the key enzyme of myo-inositol synthesis, which is a central molecule required for cell metabolism and plant growth as a precursor to a large variety of compounds. A full-length fragment of MfMIPS1 cDNA was cloned from Medicago falcata that is more cold-tolerant than Medicago sativa. While MfMIPS1 transcript was induced in response to cold, dehydration and salt stress, MIPS transcript and myo-inositol were maintained longer and at a higher level in M. falcata than in M. sativa during cold acclimation at 5 °C. MfMIPS1 transcript was induced by hydrogen peroxide (H(2) O(2)) and nitric oxide (NO), but was not responsive to abscisic acid (ABA). Pharmacological experiments revealed that H(2) O(2) and NO are involved in the regulation of MfMIPS1 expression by cold and dehydration, but not by salt. Overexpression of MfMIPS1 in tobacco increased the MIPS activity and levels of myo-inositol, galactinol and raffinose, resulting in enhanced resistance to chilling, drought and salt stresses in transgenic tobacco plants. It is suggested that MfMIPS1 is induced by diverse environmental factors and confers resistance to various abiotic stresses.

  4. Metabolic and structural evidence for the existence of a third species of polyphosphoinositide in cells: D-phosphatidyl-myo-inositol 3-phosphate.

    PubMed Central

    Stephens, L; Hawkins, P T; Downes, C P

    1989-01-01

    When human 1321 N1 astrocytoma cells were labelled to steady state with [3H]inositol and briefly with [32P]orthophosphate, a compound which contained both radiotracers and which co-migrated with phosphatidylinositol-myo-inositol 4-phosphate during t.l.c. could be extracted in acidic chloroform/methanol. Treatment with methylamine under conditions which lead to deacylation of conventional glycerophospholipids yielded a water-soluble moiety which was labelled with both radioisotopes and was eluted from an anion-exchange h.p.l.c. column with a retention time similar to, but distinct from, that of glycerophosphoinositol 4-phosphate. Experiments using sodium periodate and selective phosphatase enzymes to degrade this compound systematically generated a series of products which suggested the structure of the parent phospholipid was phosphatidyl-myo-inositol 3-phosphate (PtdIns3P). PtdIns3P is metabolically closely related to the pool(s) of inositol phospholipid(s) that serves as substrate(s) for an agonist-sensitive phosphoinositidase C, as the levels of PtdIns3P fell significantly when 1321 N1 cells were stimulated with carbachol. The relative rate of turnover of the inositol moiety of PtdIns3P is similar to that of both of the major polyphosphoinositides and significantly higher than that of total cellular phosphatidyl-myo-inositol. This suggests that all three polyphosphoinositides are synthesized from a common, rapidly metabolized, pool of phosphatidyl-myo-inositol. PMID:2541684

  5. Specific determination of myo-inositol in multivitamin pharmaceutical preparations by a flow injection system using a myo-inositol dehydrogenase reactor coupled with a glucose eliminating enzyme reactor.

    PubMed

    Ono, Masaki; Nakajima, Toshiaki; Itoh, Yuji; Shimada, Kenji; Yamato, Susumu

    2003-12-04

    A flow injection system for myo-inositol determination in multivitamin pharmaceutical preparations using two enzyme reactors was developed. Myo-inositol was detected using a fluorophotometer, to measure the fluorescence of NADH produced from NAD+ by a myo-inositol dehydrogenase reactor (IDR) containing myo-inositol dehydrogenase immobilized on porous glass. Enhanced interference due to excess glucose included in a multivitamin pharmaceutical preparation as a sweetener was eliminated by a glucose eliminating reactor (GER) co-immobilized with three enzymes (glucose oxidase, mutarotase and catalase). The calibration coefficient for the standard curve was 0.9993 for myo-inositol detection in the range of 1-5 microg/ml. Myo-inositol was determined even in the presence of glucose concentrations of 140-420 microg/ml. The recovery of myo-inositol added to the multivitamin pharmaceutical preparation was 99.6% (n=9).

  6. H(+)-dependent inorganic phosphate uptake in Trypanosoma brucei is influenced by myo-inositol transporter.

    PubMed

    Russo-Abrahão, Thais; Koeller, Carolina Macedo; Steinmann, Michael E; Silva-Rito, Stephanie; Marins-Lucena, Thaissa; Alves-Bezerra, Michele; Lima-Giarola, Naira Ligia; de-Paula, Iron Francisco; Gonzalez-Salgado, Amaia; Sigel, Erwin; Bütikofer, Peter; Gondim, Katia Calp; Heise, Norton; Meyer-Fernandes, José Roberto

    2017-04-01

    Trypanosoma brucei is an extracellular protozoan parasite that causes human African trypanosomiasis or "sleeping sickness". During the different phases of its life cycle, T. brucei depends on exogenous inorganic phosphate (Pi), but little is known about the transport of Pi in this organism. In the present study, we showed that the transport of (32)Pi across the plasma membrane follows Michaelis-Menten kinetics and is modulated by pH variation, with higher activity at acidic pH. Bloodstream forms presented lower Pi transport in comparison to procyclic forms, that displayed an apparent K0.5 = 0.093 ± 0.008 mM. Additionally, FCCP (H(+)-ionophore), valinomycin (K(+)-ionophore) and SCH28080 (H(+), K(+)-ATPase inhibitor) inhibited the Pi transport. Gene Tb11.02.3020, previously described to encode the parasite H(+):myo-inositol transporter (TbHMIT), was hypothesized to be potentially involved in the H(+):Pi cotransport because of its similarity with the Pho84 transporter described in S. cerevisiae and other trypanosomatids. Indeed, the RNAi mediated knockdown remarkably reduced TbHMIT gene expression, compromised cell growth and decreased Pi transport by half. In addition, Pi transport was inhibited when parasites were incubated in the presence of concentrations of myo-inositol that are above 300 μM. However, when expressed in Xenopus laevis oocytes, two-electrode voltage clamp experiments provided direct electrophysiological evidence that the protein encoded by TbHMIT is definitely a myo-inositol transporter that may be only marginally affected by the presence of Pi. These results confirmed the presence of a Pi carrier in T. brucei, similar to the H(+)-dependent inorganic phosphate system described in S. cerevisiae and other trypanosomatids. This transport system contributes to the acquisition of Pi and may be involved in the growth and survival of procyclic forms. In summary, this work presents the first description of a Pi transport system in T. brucei.

  7. Relationship Between Myo-Inositol Supplementary and Gestational Diabetes Mellitus

    PubMed Central

    Zheng, Xiangqin; Liu, Zhaozhen; Zhang, Yulong; Lin, Yuan; Song, Jianrong; Zheng, Lianghui; Lin, Sheng

    2015-01-01

    Abstract To determine whether myo-inositol supplement will increase the action of endogenous insulin, which is mainly measured by markers of insulin resistance such as homeostasis model assessment of insulin resistance. PubMed, Cochrane Library, Embase, and web of science were comprehensively searched using “gestational diabetes mellitus” and “myo-inositol” to identify relevant studies. Both subject headings and free texts were adopted. The methodological quality of the included studies were assessed and pooled analyzed by the methods recommended by the Cochrane collaboration. A total of 5 trials containing 513 participants were included. There was a significant reduction in aspects of gestational diabetes incidence (risk ratio [RR], 0.29; 95% confidence interval (95% CI), 0.19–0.44), birth weight (mean difference [MD], −116.98; 95% CI, −208.87 to −25.09), fasting glucose oral glucose tolerance test (OGTT) (MD, −0.36; 95% CI, −0.51 to −0.21), 1-h glucose OGTT (MD, −0.63; 95% CI, −1.01 to −0.26), 2-h glucose OGTT (MD, −0.45; 95% CI, −0.75 to −0.16), and related complications (odds ratio [OR], 0.28; 95% CI 0.14–0.58). On the basis of current evidence, myo-inositol supplementation reduces the development of gestational diabetes mellitus (GDM), although this conclusion requires further evaluation in large-scale, multicenter, blinded randomized controlled trials. PMID:26496267

  8. Hypotonicity-activated efflux of taurine and myo-inositol in rat inner medullary collecting duct cells: evidence for a major common pathway.

    PubMed

    Ruhfus, B; Kinne, R K

    1996-01-01

    To further characterize the hypotonicity-activated efflux pathways for the organic osmolytes taurine and myo-inositol in inner medullary collecting duct (IMCD) cells tracer fluxes of taurine and myo-inositol were investigated. The time course of activation of both fluxes after exposure of cells isolated at 600 mosm to a hypotonic medium (300 mosm by omission of sucrose) was identical with a major increase of release within the first 10 min. All 'anion channel blockers' employed proved to be strong inhibitors of both fluxes. Inhibition of myo-inositol efflux by 0.5 mM NPPB and 0.1 mM dideoxyforskolin was not significantly different from that of taurine efflux (87.7 +/- 11.4 compared to 94.6 +/- 4.6% and 98.8 +/- 2.0 compared to 95.9 +/- 3.7%). However, SITS (0.5 and 0.01 mM), DIDS (0.5 and 0.01 mM), and niflumic acid (0.5 mM) inhibited myo-inositol efflux more strongly than taurine efflux. The respective values were 65.4 +/- 4 vs. 42.9 +/- 3.6% for 0.01 mM SITS, 65.7 +/- 4.2 vs. 45.8 +/- 2.0% for 0.01 mM DIDS, and 79.5 +/- 3.5 vs. 54.2 +/- 2.5% for 0.5 mM niflumic acid. Taurine as well as myo-inositol efflux were decreased to a similar extent by 10 mM extracellular ATP (26.9 +/- 6.3 vs. 29.8 +/- 17.7% inhibition), by 10 mM extracellular cAMP (52.8 +/- 9.8 vs. 60.1 +/- 17.2% inhibition) and by reduction of the intracellular ATP content employing 2-deoxy-D-glucose (31.9 +/- 5.9 vs. 40.4 +/- 13.6% inhibition). In polarized primary cell cultures taurine and myo-inositol were released during a hypotonic shock primarily across the basal-lateral membrane, the ratio of basolateral versus apical efflux was 4.1 for taurine and 3.9 for myo-inositol. Apical fluxes were more sensitive to 0.01 mM SITS or DIDS; this was particularly evident for apical myo-inositol efflux which was inhibited by 0.01 mM SITS by 84.1 +/- 5.9% compared to 43.5 +/- 13.1% inhibition of the basolateral efflux. Thus, taurine and myo-inositol efflux show to a great extent a similar cellular distribution

  9. Unlike lithium, anticonvulsants and antidepressants do not alter rat brain myo-inositol.

    PubMed

    McGrath, Brent M; Greenshaw, Andrew J; McKay, Ryan; Slupsky, Carolyn M; Silverstone, Peter H

    2007-10-08

    Lithium is the first-line in bipolar disorder treatment. Lithium's clinical efficacy might be due to its inhibition of myo-inositol turnover in the phosphatidylinositol second messenger system. This study aimed to determine whether this action can extend to antidepressants and anticonvulsants also used to treat bipolar symptoms. Male rats were treated for 2 weeks with an intraperitoneal injection of phenelzine, fluoxetine, desipramine, carbamazepine, lamotrigine, sodium valproate or vehicle. Brains were dissected and myo-inositol concentrations were analyzed using high-field nuclear magnetic resonance spectroscopy at 18.8 T and quantified using Chenomx Profiler software. Brain regions assessed included the prefrontal, temporal and occipital cortical areas as well as the hippocampus. The main finding is that contrary to lithium, the anticonvulsants and antidepressants do not alter brain myo-inositol concentration. This suggests that these agents might work via a mechanism that is not centered on changes in myo-inositol concentration.

  10. myo-Inositol and d-Ribose Ligand Discrimination in an ABC Periplasmic Binding Protein

    PubMed Central

    Herrou, Julien

    2013-01-01

    The periplasmic binding protein (PBP) IbpA mediates the uptake of myo-inositol by the IatP-IatA ATP-binding cassette transmembrane transporter. We report a crystal structure of Caulobacter crescentus IbpA bound to myo-inositol at 1.45 Å resolution. This constitutes the first structure of a PBP bound to inositol. IbpA adopts a type I PBP fold consisting of two α-β lobes that surround a central hinge. A pocket positioned between the lobes contains the myo-inositol ligand, which binds with submicromolar affinity (0.76 ± 0.08 μM). IbpA is homologous to ribose-binding proteins and binds d-ribose with low affinity (50.8 ± 3.4 μM). On the basis of IbpA and ribose-binding protein structures, we have designed variants of IbpA with inverted binding specificity for myo-inositol and d-ribose. Five mutations in the ligand-binding pocket are sufficient to increase the affinity of IbpA for d-ribose by 10-fold while completely abolishing binding to myo-inositol. Replacement of ibpA with these mutant alleles unable to bind myo-inositol abolishes C. crescentus growth in medium containing myo-inositol as the sole carbon source. Neither deletion of ibpA nor replacement of ibpA with the high-affinity ribose binding allele affected C. crescentus growth on d-ribose as a carbon source, providing evidence that the IatP-IatA transporter is specific for myo-inositol. This study outlines the evolutionary relationship between ribose- and inositol-binding proteins and provides insight into the molecular basis upon which these two related, but functionally distinct, classes of periplasmic proteins specifically bind carbohydrate ligands. PMID:23504019

  11. Modulation of hemodynamic and vascular filtration changes in diabetic rats by dietary myo-inositol

    SciTech Connect

    Pugliese, G.; Tilton, R.G.; Speedy, A.; Santarelli, E.; Eades, D.M.; Province, M.A.; Kilo, C.; Sherman, W.R.; Williamson, J.R. )

    1990-03-01

    To assess the potential of myo-inositol-supplemented diets to prevent diabetes-induced vascular functional changes, we examined the effects of diets supplemented with 0.5, 1, or 2% myo-inositol on blood flow and vascular filtration function in nondiabetic control rats and rats with streptozocin-induced diabetes (STZ-D). After 1 mo of diabetes and dietary myo-inositol supplementation, (1) 131I-labeled bovine serum albumin (BSA) permeation of vessels was assessed in multiple tissues, (2) glomerular filtration rate (GFR) was estimated as renal plasma clearance of 57Co-labeled EDTA, (3) regional blood flows were measured with 15-microns 85Sr-labeled microspheres, and (4) endogenous albumin and IgG urinary excretion rates were quantified by radial immunodiffusion assay. In STZ-D rats, 131I-BSA tissue clearance increased significantly (2- to 4-fold) in the anterior uvea, choroid-sclera, retina, sciatic nerve, aorta, new granulation tissue, diaphragm, and kidney but was unchanged in skin, forelimb muscle, and heart. myo-Inositol-supplemented diets reduced diabetes-induced increases in 131I-BSA clearance (in a dose-dependent manner) in all tissues; however, only in new granulation tissue and diaphragm did the 2% myo-inositol diet completely normalize vascular albumin permeation. Diabetes-induced increases in GFR and in urinary albumin and IgG excretion were also substantially reduced or normalized by dietary myo-inositol supplements. Increased blood flow in anterior uvea, choroid-sclera, kidney, new granulation tissue, and skeletal muscle in STZ-D rats also was substantially reduced or normalized by the 2% myo-inositol diet. myo-Inositol had minimal if any effects on the above parameters in control rats.

  12. Synthesis of myo-inositol 1,3,4,5,6-pentakisphosphate from inositol phosphates generated by receptor activation.

    PubMed Central

    Stephens, L R; Hawkins, P T; Barker, C J; Downes, C P

    1988-01-01

    myo-[3H]Inositol 1,3,4,5,6-pentakisphosphate can be made from myo-[3H]inositol 1,4,5-trisphosphate in a rat brain homogenate or soluble fraction. Although D-myo-inositol 3,4,5,6-tetrakisphosphate can be phosphorylated by a soluble rat brain enzyme to give myo-inositol 1,3,4,5,6-pentakisphosphate, it is not an intermediate in the pathway from myo-inositol 1,4,5-trisphosphate. The intermediates in the above pathway are myo-inositol 1,3,4,5-tetrakisphosphate, myo-inositol 1,3,4-trisphosphate and myo-inositol 1,3,4,6-tetrakisphosphate [Shears, Parry, Tang, Irvine, Michell & Kirk (1987) Biochem. J. 246, 139-147; Balla, Guillemette, Baukal & Catt (1987) J. Biol. Chem. 262, 9952-9955], and it is catalysed by soluble kinase activities of similar anion-exchange mobility and Mr value. Compounds with chromatographic and chemical properties consistent with the structures myo-inositol 1,3,4,5-tetrakisphosphate, myo-inositol 1,3,4,6-tetrakisphosphate and myo-inositol 3,4,5,6-tetrakisphosphate are present in avian erythrocytes, human 1321 N1 astrocytoma cells and primary-cultured murine bone-marrow-derived macrophages. The amounts of these inositol tetrakisphosphates rise upon muscarinic cholinergic stimulation of the astrocytoma cells or stimulation of macrophages with platelet-activating factor. PMID:2845930

  13. Hysteresis in myo-inositol utilization by Salmonella Typhimurium.

    PubMed

    Hellinckx, Jessica; Fuchs, Thilo M

    2016-12-27

    Growth of Salmonella enterica serovar Typhimurium strain 14028 with myo-inositol (MI) as the sole carbon and energy source is characterized by a bistable phenotype that manifests in a growth phenotype with an extraordinarily long and length-variable lag phase. However, in the presence of hydrogen carbonate, in the absence of IolR that represses the MI degradation pathway, or if cells are already adapted to minimal medium (MM) with MI, the lag phase is drastically shortened, and the bistable phenotype is abolished. We hypothesized that memory development or hysteresis is a further characteristic of MI degradation by S. Typhimurium; therefore, we investigated the transition from a short to a long lag phase in more detail. Growth experiments demonstrated that memory on the population level is successively lost within approximately 8 hr after cells, which had been adapted to MI utilization, were transferred to lysogeny broth (LB) medium. Flow cytometry (FC) analysis using a chromosomal fusion to PiolE , a promoter controlling the expression of the enzymatic genes iolE and iolG involved in MI degradation, indicated a gradual reversion within a few hours from a population in the "ON" status with respect to iolE transcription to one that is mainly in the "OFF" status. Growth and FC experiments revealed that IolR does not affect hysteresis.

  14. Myo-inositol inhibits intestinal glucose absorption and promotes muscle glucose uptake: a dual approach study.

    PubMed

    Chukwuma, Chika Ifeanyi; Ibrahim, Mohammed Auwal; Islam, Md Shahidul

    2016-12-01

    The present study investigated the effects of myo-inositol on muscle glucose uptake and intestinal glucose absorption ex vivo as well as in normal and type 2 diabetes model of rats. In ex vivo study, both intestinal glucose absorption and muscle glucose uptake were studied in isolated rat jejunum and psoas muscle respectively in the presence of increasing concentrations (2.5 % to 20 %) of myo-inositol. In the in vivo study, the effect of a single bolus dose (1 g/kg bw) of oral myo-inositol on intestinal glucose absorption, blood glucose, gastric emptying and digesta transit was investigated in normal and type 2 diabetic rats after 1 h of co-administration with 2 g/kg bw glucose, when phenol red was used as a recovery marker. Myo-inositol inhibited intestinal glucose absorption (IC50 = 28.23 ± 6.01 %) and increased muscle glucose uptake, with (GU50 = 2.68 ± 0.75 %) or without (GU50 = 8.61 ± 0.55 %) insulin. Additionally, oral myo-inositol not only inhibited duodenal glucose absorption and reduced blood glucose increase, but also delayed gastric emptying and accelerated digesta transit in both normal and diabetic animals. Results of this study suggest that dietary myo-inositol inhibits intestinal glucose absorption both in ex vivo and in normal or diabetic rats and also promotes muscle glucose uptake in ex vivo condition. Hence, myo-inositol may be further investigated as a possible anti-hyperglycaemic dietary supplement for diabetic foods and food products.

  15. Crystal Structure and Product Analysis of an Archaeal myo-Inositol Kinase Reveal Substrate Recognition Mode and 3-OH Phosphorylation.

    PubMed

    Nagata, Ryuhei; Fujihashi, Masahiro; Sato, Takaaki; Atomi, Haruyuki; Miki, Kunio

    2015-06-09

    The TK2285 protein from Thermococcus kodakarensis was recently characterized as an enzyme catalyzing the phosphorylation of myo-inositol. Only two myo-inositol kinases have been identified so far, the TK2285 protein and Lpa3 from Zea mays, both of which belong to the ribokinase family. In either case, which of the six hydroxyl groups of myo-inositol is phosphorylated is still unknown. In addition, little is known about the myo-inositol binding mechanism of these enzymes. In this work, we determined two crystal structures: those of the TK2285 protein complexed with the substrates (ATP analogue and myo-inositol) or the reaction products formed by the enzyme. Analysis of the ternary substrates-complex structure and site-directed mutagenesis showed that five residues were involved in the interaction with myo-inositol. Structural comparison with other ribokinase family enzymes indicated that two of the five residues, Q136 and R140, are characteristic of myo-inositol kinase. The crystal structure of the ternary products-complex, which was prepared by incubating the TK2285 protein with myo-inositol and ATP, holds 1d-myo-inositol 3-phosphate (Ins(3)P) in the active site. NMR and HPLC analyses with a chiral column also indicated that the TK2285 reaction product was Ins(3)P. The results obtained here showed that the TK2285 protein specifically catalyzes the phosphorylation of the 3-OH of myo-inositol. We thus designated TK2285 as myo-inositol 3-kinase (MI3K). The precise identification of the reaction product should provide a sound basis to further explore inositol metabolism in Archaea.

  16. Purification and properties of myo-inositol-1-phosphate dehydrogenase from germinating mung bean seeds.

    PubMed

    Ghosh, B; De, B P; Biswas, B B

    1984-01-01

    A novel enzyme, myo-inositol-1-phosphate dehydrogenase, which catalyzes the conversion of myo-inositol 1-phosphate to ribulose 5-phosphate has been purified 84-fold from mung bean seedling employing several common techniques. The molecular weight of this purified enzyme has been recorded as 88,500 by Sephadex G-200 column chromatography, and in sodium dodecyl sulfate-polyacrylamide gel electrophoresis one protein band containing three subunits of Mr 32,000 each was discernible. Km values for NAD+ and myo-inositol 1-phosphate have been recorded as 2.8 X 10(-4) and 5.0 X 10(-4) M, respectively. Production of NADH in myo-inositol-1-phosphate dehydrogenase reaction has also been evidenced by measurement of NADH fluorescence. Dehydrogenation and decarboxylation of myo-inositol 1-phosphate are mediated by the same enzyme. In fact, the rate of dehydrogenation corroborates with that of decarboxylation. Stoichiometry of this reaction suggests that for the production of 1 mol of ribulose 5-phosphate 2 mol of NAD+ are reduced.

  17. Functional expression of a myo-inositol/H+ symporter from Leishmania donovani.

    PubMed Central

    Drew, M E; Langford, C K; Klamo, E M; Russell, D G; Kavanaugh, M P; Landfear, S M

    1995-01-01

    The vast majority of surface molecules in such kinetoplastid protozoa as members of the genus Leishmania contain inositol and are either glycosyl inositol phospholipids or glycoproteins that are tethered to the external surface of the plasma membrane by glycosylphosphatidylinositol anchors. We have shown that the biosynthetic precursor for these abundant glycolipids, myo-inositol, is translocated across the parasite plasma membrane by a specific transporter that is structurally related to mammalian facilitative glucose transporters. This myo-inositol transporter has been expressed and characterized in Xenopus laevis oocytes. Two-electrode voltage clamp experiments demonstrate that this protein is a sodium-independent electrogenic symporter that appears to utilize a proton gradient to concentrate myo-inositol within the cell. Immunolocalization experiments with a transporter-specific polyclonal antibody reveal the presence of this protein in the parasite plasma membrane. PMID:7565702

  18. Use of Per-C-Deuterated myo-Inositol for Study of Cell Wall Synthesis in Germinating Beans.

    PubMed

    Sasaki, K; Nagahashi, G; Gretz, M R; Taylor, I E

    1989-06-01

    Cell wall polysaccharides of the hypocotyl and roots in germinating beans (Phaseolus vulgaris L.) were selectively labeled in arabinosyl, xylosyl, and galacturonosyl residues by per-C-deuterated myo-inositol, which was introduced through 72 hours of imbibition. Glucuronate residues remained unlabeled. Selected ion gas chromatography-mass spectrometry analysis revealed that deuterium was not redistributed in these three sugar residues or into other carbohydrate residues during this conversion, suggesting that the labeled residues are formed exclusively via the myo-inositol oxidation pathway and that no glucogenesis from myo-inositol takes place during this conversion. The presence of a significant level of deuterated arabinose, xylose, and galacturonate after just 72 hours of imbibitional uptake of per-C-deuterated myo-inositol indicated that the myo-inositol oxidation pathway has a predominant role in the biosynthesis of new cell walls.

  19. Use of Per-C-Deuterated myo-Inositol for Study of Cell Wall Synthesis in Germinating Beans 1

    PubMed Central

    Sasaki, Ken; Nagahashi, Gerald; Gretz, Michael R.; Taylor, Iain E. P.

    1989-01-01

    Cell wall polysaccharides of the hypocotyl and roots in germinating beans (Phaseolus vulgaris L.) were selectively labeled in arabinosyl, xylosyl, and galacturonosyl residues by per-C-deuterated myo-inositol, which was introduced through 72 hours of imbibition. Glucuronate residues remained unlabeled. Selected ion gas chromatography-mass spectrometry analysis revealed that deuterium was not redistributed in these three sugar residues or into other carbohydrate residues during this conversion, suggesting that the labeled residues are formed exclusively via the myo-inositol oxidation pathway and that no glucogenesis from myo-inositol takes place during this conversion. The presence of a significant level of deuterated arabinose, xylose, and galacturonate after just 72 hours of imbibitional uptake of per-C-deuterated myo-inositol indicated that the myo-inositol oxidation pathway has a predominant role in the biosynthesis of new cell walls. PMID:16666828

  20. A potassium-18-crown-6 salt of a cyclic myo-inositol phosphate.

    PubMed

    Kumara Swamy, K C; Kumaraswamy, S

    2001-10-01

    The six-membered phosphorinane ring in (1,4,7,10,13,16-hexaoxacyclooctadecane)potassium 2-O-benzoyl-1,3,5-O-methylidyne-myo-inositol 4,6-cyclophosphate trihydrate, [K(C(12)H(24)O(6))](C(14)H(12)O(9)P).3H(2)O, has a boat rather than a chair conformation. The K(+) ion is eight-coordinate and is connected to one of the phosphate O atoms, one of the O atoms of the myo-inositol residue and the six O atoms of the crown ether.

  1. Involvement of Arabidopsis Hexokinase1 in Cell Death Mediated by Myo-Inositol Accumulation

    PubMed Central

    Bruggeman, Quentin; Prunier, Florence; Mazubert, Christelle; de Bont, Linda; Garmier, Marie; Lugan, Raphaël; Benhamed, Moussa; Bergounioux, Catherine; Raynaud, Cécile; Delarue, Marianne

    2015-01-01

    Programmed cell death (PCD) is essential for several aspects of plant life, including development and stress responses. We recently identified the mips1 mutant of Arabidopsis thaliana, which is deficient for the enzyme catalyzing the limiting step of myo-inositol (MI) synthesis. One of the most striking features of mips1 is the light-dependent formation of lesions on leaves due to salicylic acid (SA)-dependent PCD. Here, we identified a suppressor of PCD by screening for mutations that abolish the mips1 cell death phenotype. Our screen identified the hxk1 mutant, mutated in the gene encoding the hexokinase1 (HXK1) enzyme that catalyzes sugar phosphorylation and acts as a genuine glucose sensor. We show that HXK1 is required for lesion formation in mips1 due to alterations in MI content, via SA-dependant signaling. Using two catalytically inactive HXK1 mutants, we also show that hexokinase catalytic activity is necessary for the establishment of lesions in mips1. Gas chromatography-mass spectrometry analyses revealed a restoration of the MI content in mips1 hxk1 that it is due to the activity of the MIPS2 isoform, while MIPS3 is not involved. Our work defines a pathway of HXK1-mediated cell death in plants and demonstrates that two MIPS enzymes act cooperatively under a particular metabolic status, highlighting a novel checkpoint of MI homeostasis in plants. PMID:26048869

  2. How to Achieve High-Quality Oocytes? The Key Role of Myo-Inositol and Melatonin

    PubMed Central

    Rossetti, Paola; Corrado, Francesco; Rapisarda, Agnese Maria Chiara; Condorelli, Rosita Angela; Valenti, Gaetano; Sapia, Fabrizio; Buscema, Massimo

    2016-01-01

    Assisted reproductive technologies (ART) have experienced growing interest from infertile patients seeking to become pregnant. The quality of oocytes plays a pivotal role in determining ART outcomes. Although many authors have studied how supplementation therapy may affect this important parameter for both in vivo and in vitro models, data are not yet robust enough to support firm conclusions. Regarding this last point, in this review our objective has been to evaluate the state of the art regarding supplementation with melatonin and myo-inositol in order to improve oocyte quality during ART. On the one hand, the antioxidant effect of melatonin is well known as being useful during ovulation and oocyte incubation, two occasions with a high level of oxidative stress. On the other hand, myo-inositol is important in cellular structure and in cellular signaling pathways. Our analysis suggests that the use of these two molecules may significantly improve the quality of oocytes and the quality of embryos: melatonin seems to raise the fertilization rate, and myo-inositol improves the pregnancy rate, although all published studies do not fully agree with these conclusions. However, previous studies have demonstrated that cotreatment improves these results compared with melatonin alone or myo-inositol alone. We recommend that further studies be performed in order to confirm these positive outcomes in routine ART treatment. PMID:27651794

  3. Identification of a gene cluster enabling Lactobacillus casei BL23 to utilize myo-inositol.

    PubMed

    Yebra, María Jesús; Zúñiga, Manuel; Beaufils, Sophie; Pérez-Martínez, Gaspar; Deutscher, Josef; Monedero, Vicente

    2007-06-01

    Genome analysis of Lactobacillus casei BL23 revealed that, compared to L. casei ATCC 334, it carries a 12.8-kb DNA insertion containing genes involved in the catabolism of the cyclic polyol myo-inositol (MI). Indeed, L. casei ATCC 334 does not ferment MI, whereas strain BL23 is able to utilize this carbon source. The inserted DNA consists of an iolR gene encoding a DeoR family transcriptional repressor and a divergently transcribed iolTABCDG1G2EJK operon, encoding a complete MI catabolic pathway, in which the iolK gene probably codes for a malonate semialdehyde decarboxylase. The presence of iolK suggests that L. casei has two alternative pathways for the metabolism of malonic semialdehyde: (i) the classical MI catabolic pathway in which IolA (malonate semialdehyde dehydrogenase) catalyzes the formation of acetyl-coenzyme A from malonic semialdehyde and (ii) the conversion of malonic semialdehyde to acetaldehyde catalyzed by the product of iolK. The function of the iol genes was verified by the disruption of iolA, iolT, and iolD, which provided MI-negative strains. By contrast, the disruption of iolK resulted in a strain with no obvious defect in MI utilization. Transcriptional analyses conducted with different mutant strains showed that the iolTABCDG1G2EJK cluster is regulated by substrate-specific induction mediated by the inactivation of the transcriptional repressor IolR and by carbon catabolite repression mediated by the catabolite control protein A (CcpA). This is the first example of an operon for MI utilization in lactic acid bacteria and illustrates the versatility of carbohydrate utilization in L. casei BL23.

  4. GATA4-mediated cardiac hypertrophy induced by D-myo-inositol 1,4,5-tris-phosphate

    SciTech Connect

    Zhu Zhiming . E-mail: zhuzming@mail.dph-fsi.com; Zhu Shanjun; Liu Daoyan; Yu Zengping; Yang Yongjian; Giet, Markus van der; Tepel, Martin . E-mail: Martin.Tepel@charite.de

    2005-12-16

    We evaluated the effects of D-myo-inositol 1,4,5-tris-phosphate on cardiac hypertrophy. D-myo-inositol 1,4,5-tris-phosphate augmented cardiac hypertrophy as evidenced by its effects on DNA synthesis, protein synthesis, and expression of immediate-early genes c-myc and c-fos, {beta}-myosin heavy chain, and {alpha}-actin. The administration of D-myo-inositol 1,4,5-tris-phosphate increased the expression of nuclear factor of activated T-cells and cardiac-restricted zinc finger transcription factor (GATA4). Real-time quantitative RT-PCR showed that D-myo-inositol 1,4,5-tris-phosphate-induced GATA4 mRNA was significantly enhanced even in the presence of the calcineurin inhibitor, cyclosporine A. The effect of D-myo-inositol 1,4,5-tris-phosphate was blocked after inhibition of inositol-trisphosphate receptors but not after inhibition of c-Raf/mitogen-activated protein kinase kinase (MEK)/mitogen-activated protein kinase (ERK) or p38 mitogen-activated protein kinase pathways. The study shows that D-myo-inositol 1,4,5-tris-phosphate-induced cardiac hypertrophy is mediated by GATA4 but independent from the calcineurin pathway.

  5. In vitro effect of myo-inositol on sperm motility in normal and oligoasthenospermia patients undergoing in vitro fertilization.

    PubMed

    Artini, P G; Casarosa, E; Carletti, E; Monteleone, P; Di Noia, A; Di Berardino, O M

    2017-02-01

    It is a known fact that abnormal seminal liquid specimens contain abnormal amounts of oxygen free radicals and reactive oxygen species (ROS), and that the use of antioxidant molecules both in vivo and in vitro leads to improvement of semen quality in terms of motility, reduction in DNA damage, with obvious consequences on the fertilization potential. Myo-inositol has been observed to have anti-oxidant properties and be present in much greater concentrations specifically in seminal liquid than in the blood. Moreover, there seems to be a direct relationship between myo-inositol and mitochondrial membrane potential (MMP) and sperm motility. Studies performed in vivo have demonstrated that a dietary supplementation with myo-inositol in men undergoing assisted reproduction techniques may improve sperm quality and motility in oligoasthenospermia (OAT) patients. In the following study we utilized myo-inositol in vitro to verify its effect on semen quality in both normal and OAT patients undergoing in vitro fertilization (IVF) with respect to standard sperm medium. In vitro incubation of seminal liquid carried out using myo-inositol (Andrositol-Lab, Lo.Li. Pharma-Roma, Italy) at a concentration of 15 μl/ml improved progressive motility in both normospermia and OAT subjects. In our opinion, myo-inositol may prove to be a useful strategy to improve sperm preparation for clinical use in IVF.

  6. A chromogenic substrate for phosphatidylinositol-specific phospholipase C: 4-nitrophenyl myo-inositol-1-phosphate.

    PubMed

    Shashidhar, M S; Volwerk, J J; Griffith, O H; Keana, J F

    1991-12-01

    A chromogenic water-soluble substrate for phosphatidylinositol-specific phospholipase C was synthesized starting from myo-inositol employing isopropylidene and 4-methoxytetrahydropyranyl protecting groups. In this analogue of phosphatidylinositol, 4-nitrophenol replaces the diacylglycerol moiety, resulting in synthetic, racemic 4-nitrophenyl myo-inositol-1-phosphate. Using this synthetic substrate a rapid, convenient and sensitive spectrophotometric assay for the phosphatidylinositol-specific phospholipase C from Bacillus cereus was developed. Initial rates of the cleavage of the nitrophenol substrate were linear with time and the amount of enzyme used. At pH 7.0, specific activities for the B. cereus enzyme were 77 and 150 mumol substrate cleaved min-1 (mg protein)-1 at substrate concentrations of 1 and 2 mM, respectively. Under these conditions, less than 50 ng quantities of enzyme were easily detected. The chromogenic substrate was stable during long term storage (6 months) as a solid at -20 degrees C.

  7. An Uncharacterized Member of the Ribokinase Family in Thermococcus kodakarensis Exhibits myo-Inositol Kinase Activity*

    PubMed Central

    Sato, Takaaki; Fujihashi, Masahiro; Miyamoto, Yukika; Kuwata, Keiko; Kusaka, Eriko; Fujita, Haruo; Miki, Kunio; Atomi, Haruyuki

    2013-01-01

    Here we performed structural and biochemical analyses on the TK2285 gene product, an uncharacterized protein annotated as a member of the ribokinase family, from the hyperthermophilic archaeon Thermococcus kodakarensis. The three-dimensional structure of the TK2285 protein resembled those of previously characterized members of the ribokinase family including ribokinase, adenosine kinase, and phosphofructokinase. Conserved residues characteristic of this protein family were located in a cleft of the TK2285 protein as in other members whose structures have been determined. We thus examined the kinase activity of the TK2285 protein toward various sugars recognized by well characterized ribokinase family members. Although activity with sugar phosphates and nucleosides was not detected, kinase activity was observed toward d-allose, d-lyxose, d-tagatose, d-talose, d-xylose, and d-xylulose. Kinetic analyses with the six sugar substrates revealed high Km values, suggesting that they were not the true physiological substrates. By examining activity toward amino sugars, sugar alcohols, and disaccharides, we found that the TK2285 protein exhibited prominent kinase activity toward myo-inositol. Kinetic analyses with myo-inositol revealed a greater kcat and much lower Km value than those obtained with the monosaccharides, resulting in over a 2,000-fold increase in kcat/Km values. TK2285 homologs are distributed among members of Thermococcales, and in most species, the gene is positioned close to a myo-inositol monophosphate synthase gene. Our results suggest the presence of a novel subfamily of the ribokinase family whose members are present in Archaea and recognize myo-inositol as a substrate. PMID:23737529

  8. Treatment of hirsutism with myo-inositol: a prospective clinical study.

    PubMed

    Minozzi, M; D'Andrea, G; Unfer, V

    2008-10-01

    The aim of this study was to evaluate the effects of myo-inositol treatment in hirsute women; changes in lipid pattern and insulin sensitivity were also considered. Forty-six hirsute women were enrolled at the first Institute of Obstetrics and Gynecology and evaluated at baseline and after receiving myo-inositol therapy for 6 months. Body mass index (BMI), hirsutism, serum concentrations of total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, apolipoprotein B, lipoprotein(a), serum adrenal and ovarian androgens, fasting glucose and insulin concentrations were evaluated. No changes in BMI were observed. The hirsutism decreased after therapy (P < 0.001). Total androgens, FSH and LH concentrations decreased while oestradiol concentrations increased. There was a slight non-significant decrease in total cholesterol concentrations, an increase in HDL cholesterol concentrations and a decrease in LDL cholesterol concentrations. No significant changes were observed in serum triglyceride, apolipoprotein B and lipoprotein(a) concentrations. Insulin resistance (P < 0.01), analysed by homeostasis model assessment, was reduced significantly after therapy. Administration of oral myo-inositol significantly reduced hirsutism and hyperandrogenism and ameliorated the abnormal metabolic profile of women with hirsutism.

  9. Purification, crystallization and preliminary crystallographic analysis of mouse myo-inositol oxygenase

    SciTech Connect

    Brown, Peter M. Caradoc-Davies, Tom T.; Dickson, James M.; Cooper, Garth J. S.; Loomes, Kerry M.; Baker, Edward N.

    2006-08-01

    Mouse myo-inositol oxygenase, a key enzyme involved in inositol catabolism, has been expressed, purified and crystallized in a form suitable for structure determination by X-ray crystallography. Myo-inositol oxygenase (MIOX) catalyzes the novel oxidative cleavage of myo-inositol (MI) and its epimer d-chiro inositol (DCI) to d-glucuronate. MIOX utilizes an Fe{sup II}/Fe{sup III} binuclear iron centre for the dioxygen-dependent cleavage of the C1—C6 bond in MI. Despite its key role in inositol metabolism, the structural basis of its unique four-electron oxidation mechanism and its substrate specificity remain unknown. In order to answer these questions and to facilitate the use of this key enzyme for the development of new therapeutic strategies for diabetes, the mouse enzyme has been cloned, expressed in Escherichia coli, purified and crystallized from 4.4 M sodium formate. The crystals belong to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 44.87, b = 77.26, c = 84.84 Å, and diffract to 2.8 Å resolution.

  10. Isolation and identification of myo-inositol crystals from dragon fruit (Hylocereus polyrhizus).

    PubMed

    Rebecca, Ow Phui San; Boyce, Amru Nasrulhaq; Somasundram, Chandran

    2012-04-17

    Crystals isolated from Hylocereus polyrhizus were analyzed using four different approaches--X-ray Crystallography, High Performance Liquid Chromatography (HPLC), Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) and Nuclear Magnetic Resonance (NMR) and identified as myo-inositol. The X-ray crystallography analysis showed that the unit-cell parameters were: a = 6.6226 (3) Å, b = 12.0462 (5) Å, c = 18.8942 (8) Å, α = 90.00, β = 93.98, δ = 90.00. The purity of the crystals were checked using HPLC, whereupon a clean single peak was obtained at 4.8 min with a peak area of 41232 μV*s. The LC-MS/MS technique, which is highly sensitive and selective, was used to provide a comparison of the isolated crystals with a myo-inositol standard where the results gave an identical match for both precursor and product ions. NMR was employed to confirm the molecular structure and conformation of the crystals, and the results were in agreement with the earlier results in this study. The discovery of myo-inositol crystals in substantial amount in H. polyrhizus has thus far not been reported and this is an important finding which will increase the marketability and importance of H. polyrhizus as a crop with a wide array of health properties.

  11. A role for inositol hexakisphosphate in the maintenance of basal resistance to plant pathogens.

    PubMed

    Murphy, Alex M; Otto, Bettina; Brearley, Charles A; Carr, John P; Hanke, David E

    2008-11-01

    Phytic acid (myo-inositol hexakisphosphate, InsP6) is an important phosphate store and signal molecule in plants. However, low-phytate plants are being developed to minimize the negative health effects of dietary InsP6 and pollution caused by undigested InsP6 in animal waste. InsP6 levels were diminished in transgenic potato plants constitutively expressing an antisense gene sequence for myo-inositol 3-phosphate synthase (IPS, catalysing the first step in InsP6 biosynthesis) or Escherichia coli polyphosphate kinase. These plants were less resistant to the avirulent pathogen potato virus Y and the virulent pathogen tobacco mosaic virus (TMV). In Arabidopsis thaliana, mutation of the gene for the enzyme catalysing the final step of InsP6 biosynthesis (InsP5 2-kinase) also diminished InsP6 levels and enhanced susceptibility to TMV and to virulent and avirulent strains of the bacterial pathogen Pseudomonas syringae. Arabidopsis thaliana has three IPS genes (AtIPS1-3). Mutant atips2 plants were depleted in InsP6 and were hypersusceptible to TMV, turnip mosaic virus, cucumber mosaic virus and cauliflower mosaic virus as well as to the fungus Botrytis cinerea and to P. syringae. Mutant atips2 and atipk1 plants were as hypersusceptible to infection as plants unable to accumulate salicylic acid (SA) but their increased susceptibility was not due to reduced levels of SA. In contrast, mutant atips1 plants, which were also depleted in InsP6, were not compromised in resistance to pathogens, suggesting that a specific pool of InsP6 regulates defence against phytopathogens.

  12. Sugar-metal ion interactions: the complicated coordination structures of cesium ion with D-ribose and myo-inositol.

    PubMed

    Hu, Haijian; Xue, Junhui; Wen, Xiaodong; Li, Weihong; Zhang, Chao; Yang, Limin; Xu, Yizhuang; Zhao, Guozhong; Bu, Xiaoxia; Liu, Kexin; Chen, Jia'er; Wu, Jinguang

    2013-11-18

    The novel cesium chloride-D-ribose complex (CsCl·C5H10O5; Cs-R) and cesium chloride-myo-inositol complex (CsCl·C6H12O6; Cs-I) have been synthesized and characterized using X-ray diffraction and FTIR, FIR, THz, and Raman spectroscopy. Cs(+) is eight-coordinated to three chloride ions, O1 and O2 from one D-ribose molecule, O1 from another D-ribose molecule, and O4 and O5 from the third D-ribose molecule in Cs-R. For one D-ribose molecule, the oxygen atom O1 in the ring is coordinated to two cesium ions as an oxygen bridge, O2 is cocoordinated with O1 to one of the two cesium ions, and O4 and O5 are coordinated to the third cesium ion, respectively. O3 does not coordinate to metal ions and only takes part in forming hydrogen bonds. One chloride ion is connected to three cesium ions. Thus, a complicated structure of Cs-D-ribose forms. For Cs-I, Cs(+) is 10-coordinated to three chloride ions, O1 and O2 from one myo-inositol molecule, O3 and O4 from another myo-inositol molecule, O5 and O6 from the third myo-inositol molecule, and O6 from the fourth myo-inositol molecule. One metal ion is connected to four ligands, and one myo-inositol is coordinated to four Cs(+) ions, which is also a complicated coordination structure. Crystal structure results, FTIR, FIR, THz, and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride-D-ribose and cesium chloride-myo-inositol complexes.

  13. Metabolism of myo-Inositol by Legionella pneumophila Promotes Infection of Amoebae and Macrophages

    PubMed Central

    Manske, Christian; Schell, Ursula

    2016-01-01

    ABSTRACT Legionella pneumophila is a natural parasite of environmental amoebae and the causative agent of a severe pneumonia termed Legionnaires' disease. The facultative intracellular pathogen employs a bipartite metabolism, where the amino acid serine serves as the major energy supply, while glycerol and glucose are mainly utilized for anabolic processes. The L. pneumophila genome harbors the cluster lpg1653 to lpg1649 putatively involved in the metabolism of the abundant carbohydrate myo-inositol (here termed inositol). To assess inositol metabolism by L. pneumophila, we constructed defined mutant strains lacking lpg1653 or lpg1652, which are predicted to encode the inositol transporter IolT or the inositol-2-dehydrogenase IolG, respectively. The mutant strains were not impaired for growth in complex or defined minimal media, and inositol did not promote extracellular growth. However, upon coinfection of Acanthamoeba castellanii, the mutants were outcompeted by the parental strain, indicating that the intracellular inositol metabolism confers a fitness advantage to the pathogen. Indeed, inositol added to L. pneumophila-infected amoebae or macrophages promoted intracellular growth of the parental strain, but not of the ΔiolT or ΔiolG mutant, and growth stimulation by inositol was restored by complementation of the mutant strains. The expression of the Piol promoter and bacterial uptake of inositol required the alternative sigma factor RpoS, a key virulence regulator of L. pneumophila. Finally, the parental strain and ΔiolG mutant bacteria but not the ΔiolT mutant strain accumulated [U-14C6]inositol, indicating that IolT indeed functions as an inositol transporter. Taken together, intracellular L. pneumophila metabolizes inositol through the iol gene products, thus promoting the growth and virulence of the pathogen. IMPORTANCE The environmental bacterium Legionella pneumophila is the causative agent of a severe pneumonia termed Legionnaires' disease. The

  14. High-performance reversed-phase ion-pair chromatographic study of myo-inositol phosphates. Separation of myo-inositol phosphates, some common nucleotides and sugar phosphates.

    PubMed

    Patthy, M; Balla, T; Arányi, P

    1990-12-07

    A detailed study of all the major chromatographic variables affecting the retention behaviour and separation of myo-inositol phosphates in reversed-phase ion-pair chromatographic systems was carried out. The parameters studied included the eluent concentration of the pairing ion, the eluent concentration of the organic modifier and the buffer salt, the pH of the eluent, the minimum column plate count necessary for the separation of the inositol trisphosphate isomers and isocratic and gradient modes of separation. The retention behaviour of some common nucleotides and sugar phosphates was also investigated as these phosphates present chromatographic interference problems in biochemical studies based on the cellular incorporation of [32P]Pi. The separation methods developed appear to be superior to established anion-exchange separation techniques in terms of separation speed and "mildness" of the chromatographic conditions.

  15. The Effectiveness of Myo-Inositol and D-Chiro Inositol Treatment in Type 2 Diabetes

    PubMed Central

    Di Vieste, Giacoma; Bonomo, Matteo

    2016-01-01

    Inositol has been used as a supplement in treating several pathologies such as PCOS, metabolic syndrome, and gestational diabetes. Both myo-inositol and its isomer d-chiro-inositol showed insulin mimetic effects in conditions of insulin resistance. Type 2 diabetes (T2DM) is a condition typically caused by insulin resistance. There is a lack of evidence of inositol use in T2DM. We evaluated the effectiveness and safety of myo-inositol and d-chiro-inositol treatment in T2DM. This was a pilot study involving a consecutive sample of patients with T2DM with suboptimal glycemic control (HbA1c 7.0–10.0%) already treated with glucose-lowering agents. Patients (23.1% males, mean age of 60.8 ± 11.7 years) took for three months a combination of myo-inositol (550 mg) and d-chiro-inositol (13.8 mg) orally twice a day as add-on supplement to their glucose-lowering drugs. Possible occurrence of side effects was investigated. After three months of treatment fasting blood glucose (192.6 ± 60.2 versus 160.9 ± 36.4; p = 0.02) and HbA1c levels (8.6 ± 0.9 versus 7.7 ± 0.9; p = 0.02) significantly decreased compared to baseline. There was no significant difference in blood pressure, lipid profile, and BMI levels. None of the participants reported side effects. In conclusion, a supplementation with a combination of myo- and d-chiro-inositol is an effective and safe strategy for improving glycemic control in T2DM. PMID:27807448

  16. Salinity-induced regulation of the myo-inositol biosynthesis pathway in tilapia gill epithelium.

    PubMed

    Sacchi, Romina; Li, Johnathon; Villarreal, Fernando; Gardell, Alison M; Kültz, Dietmar

    2013-12-15

    The myo-inositol biosynthesis (MIB) pathway converts glucose-6-phosphate to the compatible osmolyte myo-inositol that protects cells from osmotic stress. Using proteomics, the enzymes that constitute the MIB pathway, myo-inositol phosphate synthase (MIPS) and inositol monophosphatase 1 (IMPA1), are identified in tilapia (Oreochromis mossambicus) gill epithelium. Targeted, quantitative, label-free proteomics reveals that they are both upregulated during salinity stress. Upregulation is stronger when fish are exposed to severe (34 ppt acute and 90 ppt gradual) relative to moderate (70 ppt gradual) salinity stress. IMPA1 always responds more strongly than MIPS, suggesting that MIPS is more stable during salinity stress. MIPS is N-terminally acetylated and the corresponding peptide increases proportionally to MIPS protein, while non-acetylated N-terminal peptide is not detectable, indicating that MIPS acetylation is constitutive and may serve to stabilize the protein. Hyperosmotic induction of MIPS and IMPA1 is confirmed using western blot and real-time qPCR and is much higher at the mRNA than at the protein level. Two distinct MIPS mRNA variants are expressed in the gill, but one is more strongly regulated by salinity than the other. A single MIPS gene is encoded in the tilapia genome whereas the zebrafish genome lacks MIPS entirely. The genome of euryhaline tilapia contains four IMPA genes, two of which are expressed, but only one is salinity regulated in gill epithelium. The genome of stenohaline zebrafish contains a single IMPA gene. We conclude that the MIB pathway represents a major salinity stress coping mechanism that is regulated at multiple levels in euryhaline fish but absent in stenohaline zebrafish.

  17. Characterization of myo-inositol utilization by Corynebacterium glutamicum: the stimulon, identification of transporters, and influence on L-lysine formation.

    PubMed

    Krings, Eva; Krumbach, Karin; Bathe, Brigitte; Kelle, Ralf; Wendisch, Volker F; Sahm, Hermann; Eggeling, Lothar

    2006-12-01

    Although numerous bacteria possess genes annotated iol in their genomes, there have been very few studies on the possibly associated myo-inositol metabolism and its significance for the cell. We found that Corynebacterium glutamicum utilizes myo-inositol as a carbon and energy source, enabling proliferation with a high maximum rate of 0.35 h-1. Whole-genome DNA microarray analysis revealed that 31 genes respond to myo-inositol utilization, with 21 of them being localized in two clusters of >14 kb. A set of genomic mutations and functional studies yielded the result that some genes in the two clusters are redundant, and only cluster I is necessary for catabolizing the polyol. There are three genes which encode carriers belonging to the major facilitator superfamily and which exhibit a >12-fold increased mRNA level on myo-inositol. As revealed by mutant characterizations, one carrier is not involved in myo-inositol uptake whereas the other two are active and can completely replace each other with apparent Kms for myo-inositol as a substrate of 0.20 mM and 0.45 mM, respectively. Interestingly, upon utilization of myo-inositol, the L-lysine yield is 0.10 mol/mol, as opposed to 0.30 mol/mol, with glucose as the substrate. This is probably not only due to myo-inositol metabolism alone since a mixture of 187 mM glucose and 17 mM myo-inositol, where the polyol only contributes 8% of the total carbon, reduced the L-lysine yield by 29%. Moreover, genome comparisons with other bacteria highlight the core genes required for growth on myo-inositol, whose metabolism is still weakly defined.

  18. Production of partially phosphorylated myo-inositol phosphates using phytases immobilised on magnetic nanoparticles.

    PubMed

    Greiner, Ralf; Konietzny, Ursula; Blackburn, Daniel Menezes; Jorquera, Milko A

    2013-08-01

    Phytases of different origin were covalently bound onto Fe3O4 magnetic nanoparticles (12 nm). Binding efficiencies of all three phytases were well above 70% relative to the number of aldehyde groups available on the surface of the magnetic nanoparticles. Temperature stability for all three phytases was enhanced as a consequence of immobilisation, whereas pH dependence of enzyme activity was not affected. Maximum catalytic activity of the immobilised phytases was found at 60°C (rye), 65°C (Aspergillus niger) and 70°C (Escherichia albertii). The immobilised enzymes exhibited the same excellent substrate specificities and unique myo-inositol phosphate phosphatase activities as their soluble counterparts. However, the catalytic turnover number dropped drastically for the immobilised phytases. The amount of the desired partially phosphorylated myo-inositol phosphate isomer could be easily controlled by the contact time of substrate solution and immobilised enzymes. The immobilised phytases showed a high operational stability by retaining almost full activity even after fifty uses.

  19. Recombinant expression of a functional myo-inositol-1-phosphate synthase (MIPS) in Mycobacterium smegmatis.

    PubMed

    Huang, Xinyi; Hernick, Marcy

    2015-10-01

    Myo-inositol-1-phosphate synthase (MIPS, E.C. 5.5.1.4) catalyzes the first step in inositol production-the conversion of glucose-6-phosphate (Glc-6P) to myo-inositol-1-phosphate. While the three dimensional structure of MIPS from Mycobacterium tuberculosis has been solved, biochemical studies examining the in vitro activity have not been reported to date. Herein we report the in vitro activity of mycobacterial MIPS expressed in E. coli and Mycobacterium smegmatis. Recombinant expression in E. coli yields a soluble protein capable of binding the NAD(+) cofactor; however, it has no significant activity with the Glc-6P substrate. In contrast, recombinant expression in M. smegmatis mc(2)4517 yields a functionally active protein. Examination of structural data suggests that MtMIPS expressed in E. coli adopts a fold that is missing a key helix containing two critical (conserved) Lys side chains, which likely explains the inability of the E. coli expressed protein to bind and turnover the Glc-6P substrate. Recombinant expression in M. smegmatis may yield a protein that adopts a fold in which this key helix is formed enabling proper positioning of important side chains, thereby allowing for Glc-6P substrate binding and turnover. Detailed mechanistic studies may be feasible following optimization of the recombinant MIPS expression protocol in M. smegmatis.

  20. Dephosphorylation of 1D-myo-inositol 1,4-bisphosphate in rat liver.

    PubMed Central

    Morris, A J; Storey, D J; Downes, C P; Michell, R H

    1988-01-01

    Dephosphorylation of 1D-myo-inositol 1,4-bisphosphate [Ins(1,4)P2] in rat liver is catalysed by a cytosolic phosphatase that removes the 1-phosphate group. The Km for Ins(1,4)P2 is approx. 17 microM. Li+ (100 mM) causes 50% inhibition of Ins(1,4)P2 phosphatase activity when activity is measured at the very low substrate concentration of 10 nM, but on raising the substrate concentration to 100 microM there is a greater than 10-fold increase in sensitivity to Li+, suggesting that Li+ acts mainly, but not entirely, as an uncompetitive inhibitor of Ins(1,4)P2 phosphatase. In addition, rat liver cytosol shows Li+-sensitive phosphatase activity against 1D-myo-inositol 1-,3- and 4-monophosphates. The Ins(1,4)P2 1-phosphatase and inositol monophosphatase activities all share an apparent Mr of 47 x 10(3), as determined by gel-filtration chromatography. However, the Ins(1,4)P2 1-phosphatase is more sensitive to inactivation by heat, and can be separated from inositol monophosphatase activity by anion-exchange chromatography. We conclude that rat liver cytosol contains an Ins(1,4)P2 1-phosphatase that is distinct from, but in many ways similar to, inositol monophosphatase. PMID:2848493

  1. The phosphatidyl-myo-inositol mannosyltransferase PimA is essential for Mycobacterium tuberculosis growth in vitro and in vivo.

    PubMed

    Boldrin, Francesca; Ventura, Marcello; Degiacomi, Giulia; Ravishankar, Sudha; Sala, Claudia; Svetlikova, Zuzana; Ambady, Anisha; Dhar, Neeraj; Kordulakova, Jana; Zhang, Ming; Serafini, Agnese; Vishwas, K G; Vishwas, V G; Kolly, Gaëlle S; Kumar, Naveen; Palù, Giorgio; Guerin, Marcelo E; Mikusova, Katarina; Cole, Stewart T; Manganelli, Riccardo

    2014-10-01

    The cell envelope of Mycobacterium tuberculosis contains glycans and lipids of peculiar structure that play prominent roles in the biology and pathogenesis of tuberculosis. Consequently, the chemical structure and biosynthesis of the cell wall have been intensively investigated in order to identify novel drug targets. Here, we validate that the function of phosphatidyl-myo-inositol mannosyltransferase PimA is vital for M. tuberculosis in vitro and in vivo. PimA initiates the biosynthesis of phosphatidyl-myo-inositol mannosides by transferring a mannosyl residue from GDP-Man to phosphatidyl-myo-inositol on the cytoplasmic side of the plasma membrane. To prove the essential nature of pimA in M. tuberculosis, we constructed a pimA conditional mutant by using the TetR-Pip off system and showed that downregulation of PimA expression causes bactericidality in batch cultures. Consistent with the biochemical reaction catalyzed by PimA, this phenotype was associated with markedly reduced levels of phosphatidyl-myo-inositol dimannosides, essential structural components of the mycobacterial cell envelope. In addition, the requirement of PimA for viability was clearly demonstrated during macrophage infection and in two different mouse models of infection, where a dramatic decrease in viable counts was observed upon silencing of the gene. Notably, depletion of PimA resulted in complete clearance of the mouse lungs during both the acute and chronic phases of infection. Altogether, the experimental data highlight the importance of the phosphatidyl-myo-inositol mannoside biosynthetic pathway for M. tuberculosis and confirm that PimA is a novel target for future drug discovery programs.

  2. The Phosphatidyl-myo-Inositol Mannosyltransferase PimA Is Essential for Mycobacterium tuberculosis Growth In Vitro and In Vivo

    PubMed Central

    Boldrin, Francesca; Ventura, Marcello; Degiacomi, Giulia; Ravishankar, Sudha; Sala, Claudia; Svetlikova, Zuzana; Ambady, Anisha; Dhar, Neeraj; Kordulakova, Jana; Zhang, Ming; Serafini, Agnese; Vishwas, V. G.; Kolly, Gaëlle S.; Kumar, Naveen; Palù, Giorgio; Guerin, Marcelo E.; Mikusova, Katarina; Cole, Stewart T.

    2014-01-01

    The cell envelope of Mycobacterium tuberculosis contains glycans and lipids of peculiar structure that play prominent roles in the biology and pathogenesis of tuberculosis. Consequently, the chemical structure and biosynthesis of the cell wall have been intensively investigated in order to identify novel drug targets. Here, we validate that the function of phosphatidyl-myo-inositol mannosyltransferase PimA is vital for M. tuberculosis in vitro and in vivo. PimA initiates the biosynthesis of phosphatidyl-myo-inositol mannosides by transferring a mannosyl residue from GDP-Man to phosphatidyl-myo-inositol on the cytoplasmic side of the plasma membrane. To prove the essential nature of pimA in M. tuberculosis, we constructed a pimA conditional mutant by using the TetR-Pip off system and showed that downregulation of PimA expression causes bactericidality in batch cultures. Consistent with the biochemical reaction catalyzed by PimA, this phenotype was associated with markedly reduced levels of phosphatidyl-myo-inositol dimannosides, essential structural components of the mycobacterial cell envelope. In addition, the requirement of PimA for viability was clearly demonstrated during macrophage infection and in two different mouse models of infection, where a dramatic decrease in viable counts was observed upon silencing of the gene. Notably, depletion of PimA resulted in complete clearance of the mouse lungs during both the acute and chronic phases of infection. Altogether, the experimental data highlight the importance of the phosphatidyl-myo-inositol mannoside biosynthetic pathway for M. tuberculosis and confirm that PimA is a novel target for future drug discovery programs. PMID:25049093

  3. A myo-inositol-1-phosphate synthase gene, IbMIPS1, enhances salt and drought tolerance and stem nematode resistance in transgenic sweet potato.

    PubMed

    Zhai, Hong; Wang, Feibing; Si, Zengzhi; Huo, Jinxi; Xing, Lei; An, Yanyan; He, Shaozhen; Liu, Qingchang

    2016-02-01

    Myo-inositol-1-phosphate synthase (MIPS) is a key rate limiting enzyme in myo-inositol biosynthesis. The MIPS gene has been shown to improve tolerance to abiotic stresses in several plant species. However, its role in resistance to biotic stresses has not been reported. In this study, we found that expression of the sweet potato IbMIPS1 gene was induced by NaCl, polyethylene glycol (PEG), abscisic acid (ABA) and stem nematodes. Its overexpression significantly enhanced stem nematode resistance as well as salt and drought tolerance in transgenic sweet potato under field conditions. Transcriptome and real-time quantitative PCR analyses showed that overexpression of IbMIPS1 up-regulated the genes involved in inositol biosynthesis, phosphatidylinositol (PI) and ABA signalling pathways, stress responses, photosynthesis and ROS-scavenging system under salt, drought and stem nematode stresses. Inositol, inositol-1,4,5-trisphosphate (IP3 ), phosphatidic acid (PA), Ca(2+) , ABA, K(+) , proline and trehalose content was significantly increased, whereas malonaldehyde (MDA), Na(+) and H2 O2 content was significantly decreased in the transgenic plants under salt and drought stresses. After stem nematode infection, the significant increase of inositol, IP3 , PA, Ca(2+) , ABA, callose and lignin content and significant reduction of MDA content were found, and a rapid increase of H2 O2 levels was observed, peaked at 1 to 2 days and thereafter declined in the transgenic plants. This study indicates that the IbMIPS1 gene has the potential to be used to improve the resistance to biotic and abiotic stresses in plants.

  4. Reaching for mechanistic consensus across life kingdoms: structure and insights into catalysis of the myo-inositol-1-phosphate synthase (mIPS) from Archaeoglobus fulgidus.

    PubMed

    Stieglitz, Kimberly A; Yang, Hongying; Roberts, Mary F; Stec, Boguslaw

    2005-01-11

    myo-Inositol-1-phosphate synthase (mIPS) catalyzes the first step in the synthesis of l-myo-inositol-1-phosphate. We have solved and refined the structure of the mIPS from the hyperthermophilic sulfate reducer Archaeoglobus fulgidus at 1.9 A resolution. The enzyme crystallized from poly(ethylene glycol) in the P1 space group with one tetramer in the asymmetric unit and provided a view of the entire biologically active oligomer. Despite significant changes in sequence length and amino acid composition, the general architecture of the archaeal enzyme is similar to that of the eukaryotic mIPS from Saccharomyces cerevisiae and bacterial mIPS from Mycobacterium tuberculosis. The enhanced thermostability of the archaeal enzyme as compared to that from yeast is consistent with deletion of a number of surface loops that results in a significantly smaller protein. In the structure of the A. fulgidus mIPS, the active sites of all four subunits were fully ordered and contained NAD(+) and inorganic phosphate. The structure also contained a single metal ion (identified as K(+)) in two of the four subunits. The analysis of the electrostatic potential maps of the protein suggested the presence of a second metal-ion-binding site in close proximity to the first metal ion and NAD(+). The modeling of the substrate and known inhibitors suggests a critical role for the second metal ion in catalysis and provides insights into the common elements of the catalytic cycle in enzymes from different life kingdoms.

  5. Treatment with Myo-Inositol and Selenium Ensures Euthyroidism in Patients with Autoimmune Thyroiditis

    PubMed Central

    Basciani, Sabrina

    2017-01-01

    Clinical evidences have highlighted the efficacy of myo-inositol and selenium in the treatment of autoimmune thyroiditis. Aim of this study was to further analyze the role of myo-inositol plus selenium (Myo-Ins-Se) in restoring a normal thyroid function of Hashimoto's patients with subclinical hypothyroidism. Eighty-six patients with Hashimoto's thyroiditis having thyroid-stimulating hormone (TSH) levels between 3 and 6 mIU/L, elevated serum antithyroid peroxidase (TPOAb) and/or antithyroglobulin (TgAb), and normal free thyroxine (fT4) and free triiodothyronine (fT3) levels were enrolled in the study: one hyperthyroid subject with TSH about 0.14 μU/ml was included in this trial as a single case. Patients were assigned to receive Myo-Ins-Se. TSH, TPOAb, and TgAb levels were significantly decreased in patients treated with combined Myo-Ins-Se after 6 months of treatment. In addition, a significant fT3 and fT4 increase, along with an amelioration of their quality of life, was observed. Remarkably, TSH values of the hyperthyroid patient increased from 0.14 μU/ml up to 1.02 μU/ml, showing a complete restoration of TSH values at a normal range. In conclusion, the administration of Myo-Ins-Se is significantly effective in decreasing TSH, TPOAb, and TgAb levels, as well as enhancing thyroid hormones and personal wellbeing, therefore restoring euthyroidism in patients diagnosed with autoimmune thyroiditis. PMID:28293260

  6. Myo-inositol administration positively effects ovulation induction and intrauterine insemination in patients with polycystic ovary syndrome: a prospective, controlled, randomized trial.

    PubMed

    Emekçi Özay, Özlen; Özay, Ali Cenk; Çağlıyan, Erkan; Okyay, Recep Emre; Gülekli, Bülent

    2017-03-03

    Objectıve: The aim of the study is to investigate the effect of myo-inositol (MYO) on pregnancy rates of patients diagnosed with polycystic ovary syndrome (PCOS) who undergone controlled ovulation induction and intrauterine insemination (IUI).

  7. Treating Woman with Myo-Inositol Vaginal Suppositories Improves Partner's Sperm Motility and Fertility

    PubMed Central

    Poverini, Roberta; Lisi, Rosella; Carra, Maria Cristina; Lisi, Franco

    2016-01-01

    Motility is the feature that allows spermatozoa to actively reach and penetrate the female gamete during fertilization. When this function is altered, and especially decreased, troubles in conceiving may occur. In this study, we demonstrated that treating fertile women with myo-inositol (MI) vaginal suppositories ameliorated their partners' sperm motility and also positively affected their conceiving capacity, without changes in cervical mucus structural and biochemical characteristics. Indeed, by means of the postcoital test on female cervical mucus, a significant improvement especially in progressive sperm motility was recorded after MI suppository use. Concomitantly, after MI treatment, a reduction of immotile spermatozoa percentage was observed. Importantly, MI vaginal supplementation positively correlated with a pregnancy for 5 of the 50 couples enrolled in the study, leading us to speculate that this substance may substantially contribute to create in the cervical mucus an ideal milieu that makes spermatozoa more motile and functionally able to fertilize. Even though the detailed mechanism is still unclear, these results should encourage MI vaginal use for the clinical improvement of male infertility, through their partners. PMID:27403162

  8. Treating Woman with Myo-Inositol Vaginal Suppositories Improves Partner's Sperm Motility and Fertility.

    PubMed

    Montanino Oliva, Mario; Poverini, Roberta; Lisi, Rosella; Carra, Maria Cristina; Lisi, Franco

    2016-01-01

    Motility is the feature that allows spermatozoa to actively reach and penetrate the female gamete during fertilization. When this function is altered, and especially decreased, troubles in conceiving may occur. In this study, we demonstrated that treating fertile women with myo-inositol (MI) vaginal suppositories ameliorated their partners' sperm motility and also positively affected their conceiving capacity, without changes in cervical mucus structural and biochemical characteristics. Indeed, by means of the postcoital test on female cervical mucus, a significant improvement especially in progressive sperm motility was recorded after MI suppository use. Concomitantly, after MI treatment, a reduction of immotile spermatozoa percentage was observed. Importantly, MI vaginal supplementation positively correlated with a pregnancy for 5 of the 50 couples enrolled in the study, leading us to speculate that this substance may substantially contribute to create in the cervical mucus an ideal milieu that makes spermatozoa more motile and functionally able to fertilize. Even though the detailed mechanism is still unclear, these results should encourage MI vaginal use for the clinical improvement of male infertility, through their partners.

  9. Which pulse sequence is optimal for myo-inositol detection at 3T?

    PubMed

    Hancu, Ileana

    2009-05-01

    Optimized myo-inositol (mI) detection is important for diagnosing and monitoring a multitude of pathological conditions of the brain. Simulations are presented in this work, performed to decide which pulse sequence has the most significant advantage in terms of improving repeatability and accuracy of mI measurements at 3T over the pulse sequence used typically in the clinic, a TE = 35 ms PRESS sequence. Five classes of pulse sequences, four previously suggested for optimized mI detection (a short TE PRESS, a Carr-Purcell PRESS sequence, an optimized STEAM sequence, an optimized zero quantum filter), and one optimized for mI detection in this work (a single quantum filter) were compared to a standard, TE = 35 ms pulse sequence. While limiting the SNR of an acquisition to the equivalent SNR of a spectrum acquired in 5 min from an 8 cc voxel, it was found through simulations that the most repeatable mI measurements would be obtained with a Carr-Purcell sequence. This sequence was implemented in a clinical scanner, and improved mI measurements were demonstrated in vivo.

  10. Myo-Inositol Safety in Pregnancy: From Preimplantation Development to Newborn Animals

    PubMed Central

    Kuşcu, Nilay

    2016-01-01

    Myo-inositol (myo-Ins) has a physiological role in mammalian gametogenesis and embryonic development and a positive clinical impact on human medically assisted reproduction. We have previously shown that mouse embryo exposure to myo-Ins through preimplantation development in vitro increases proliferation activity and blastocyst production, representing an improvement in culture conditions. We have herein investigated biochemical mechanisms elicited by myo-Ins in preimplantation embryos and evaluated myo-Ins effects on postimplantation/postnatal development. To this end naturally fertilized embryos were cultured in vitro to blastocyst in the presence or absence of myo-Ins and analyzed for activation of the PKB/Akt pathway, known to modulate proliferation/survival cellular processes. In parallel, blastocyst-stage embryos were transferred into pseudopregnant females and allowed to develop to term and until weaning. Results obtained provide evidence that myo-Ins induces cellular pathways involving Akt and show that (a) exposure of preimplantation embryos to myo-Ins increases the number of blastocysts available for uterine transfer and of delivered animals and (b) the developmental patterns of mice obtained from embryos cultured in the presence or absence of myo-Ins, up to three weeks of age, overlap. These data further identify myo-Ins as a possibly important supplement for human preimplantation embryo culture in assisted reproduction technology. PMID:27698667

  11. Multibody cofactor and substrate molecular recognition in the myo-inositol monophosphatase enzyme

    PubMed Central

    Ferruz, Noelia; Tresadern, Gary; Pineda-Lucena, Antonio; De Fabritiis, Gianni

    2016-01-01

    Molecular recognition is rarely a two-body protein-ligand problem, as it often involves the dynamic interplay of multiple molecules that together control the binding process. Myo-inositol monophosphatase (IMPase), a drug target for bipolar disorder, depends on 3 Mg2+ ions as cofactor for its catalytic activity. Although the crystallographic pose of the pre-catalytic complex is well characterized, the binding process by which substrate, cofactor and protein cooperate is essentially unknown. Here, we have characterized cofactor and substrate cooperative binding by means of large-scale molecular dynamics. Our study showed the first and second Mg2+ ions identify the binding pocket with fast kinetics whereas the third ion presents a much higher energy barrier. Substrate binding can occur in cooperation with cofactor, or alone to a binary or ternary cofactor-IMPase complex, although the last scenario occurs several orders of magnitude faster. Our atomic description of the three-body mechanism offers a particularly challenging example of pathway reconstruction, and may prove particularly useful in realistic contexts where water, ions, cofactors or other entities cooperate and modulate the binding process. PMID:27440438

  12. Phenotypic, genetic and molecular characterization of a maize low phytic acid mutant (lpa241).

    PubMed

    Pilu, R; Panzeri, D; Gavazzi, G; Rasmussen, S K; Consonni, G; Nielsen, E

    2003-10-01

    Phytic acid, myo-inositol 1,2,3,4,5,6-hexakisphosphate, is the major storage compound of phosphorous (P) in plants, predominantly accumulating in seeds (up to 4-5% of dry weight) and pollen. In cereals, phytic acid is deposited in embryo and aleurone grain tissues as a mixed "phytate" salt of potassium and magnesium, although phytates contain other mineral cations such as iron and zinc. During germination, phytates are broken down by the action of phytases, releasing their P, minerals and myo-inositol which become available to the growing seedling. Phytic acid represents an anti-nutritional factor for animals, and isolation of maize low phytic acid ( lpa) mutants provides a novel approach to study its biochemical pathway and to tackle the nutritional problems associated with it. Following chemical mutagenesis of pollen, we have isolated a viable recessive mutant named lpa 241 showing about 90% reduction of phytic acid and about a tenfold increase in seed-free phosphate content. Although germination rate was decreased by about 30% compared to wild-type, developement of mutant plants was apparentely unaffected. The results of the genetic, biochemical and molecular characterization experiments carried out by SSR mapping, MDD-HPLC and RT-PCR are consistent with a mutation affecting the MIPS1S gene, coding for the first enzyme of the phytic acid biosynthetic pathway.

  13. Ectopic Expression of a Glycine soja myo-Inositol Oxygenase Gene (GsMIOX1a) in Arabidopsis Enhances Tolerance to Alkaline Stress

    PubMed Central

    Chen, Chen; Sun, Xiaoli; Duanmu, Huizi; Yu, Yang; Liu, Ailin; Xiao, Jialei; Zhu, Yanming

    2015-01-01

    Myo-inositol participates in various aspects of plant physiology, and myo-inositol oxygenase is the key enzyme of the myo-inositol oxygenation pathway. Previous studies indicated that myo-inositol oxygenase may play a role in plant responses to abiotic stresses. In this study, we focused on the functional characterization of GsMIOX1a, a remarkable alkaline stress-responsive gene of Glycine soja 07256, based on RNA-seq data. Using quantitative real-time PCR, we demonstrated that GsMIOX1a is rapidly induced by alkaline stress and expressed predominantly in flowers. We also elucidated the positive function of GsMIOX1a in the alkaline response in the wild type, atmiox1 mutant as well as GsMIOX1a-overexpressing Arabidopsis. We determined that atmiox1 mutant decreased Arabidopsis tolerance to alkaline stress, whereas GsMIOX1a overexpression increased tolerance. Moreover, the expression levels of some alkaline stress-responsive and inducible marker genes, including H+-Ppase, NADP-ME, KIN1 and RD29B, were also up-regulated in GsMIOX1a overexpression lines compared with the wild type and atmiox1 mutant. Together, these results suggest that the GsMIOX1a gene positively regulates plant tolerance to alkaline stress. This is the first report to demonstrate that ectopic expression of myo-inositol oxygenase improves alkaline tolerance in plants. PMID:26091094

  14. Direct Ionic Regulation of the Activity of Myo-Inositol Biosynthesis Enzymes in Mozambique Tilapia.

    PubMed

    Villarreal, Fernando D; Kültz, Dietmar

    2015-01-01

    Myo-inositol (Ins) is a major compatible osmolyte in many cells, including those of Mozambique tilapia (Oreochromis mossambicus). Ins biosynthesis is highly up-regulated in tilapia and other euryhaline fish exposed to hyperosmotic stress. In this study, enzymatic regulation of two enzymes of Ins biosynthesis, Ins phosphate synthase (MIPS) and inositol monophosphatase (IMPase), by direct ionic effects is analyzed. Specific MIPS and IMPase isoforms from Mozambique tilapia (MIPS-160 and IMPase 1) were selected based on experimental, phylogenetic, and structural evidence supporting their role for Ins biosynthesis during hyperosmotic stress. Recombinant tilapia IMPase 1 and MIPS-160 activity was assayed in vitro at ionic conditions that mimic changes in the intracellular milieu during hyperosmotic stress. The in vitro activities of MIPS-160 and IMPase 1 are highest at alkaline pH of 8.8. IMPase 1 catalytic efficiency is strongly increased during hyperosmolality (particularly for the substrate D-Ins-3-phosphate, Ins-3P), mainly as a result of [Na+] elevation. Furthermore, the substrate-specificity of IMPase 1 towards D-Ins-1-phosphate (Ins-1P) is lower than towards Ins-3P. Because MIPS catalysis results in Ins-3P this results represents additional evidence for IMPase 1 being the isoform that mediates Ins biosynthesis in tilapia. Our data collectively demonstrate that the Ins biosynthesis enzymes are activated under ionic conditions that cells are exposed to during hypertonicity, resulting in Ins accumulation, which, in turn, results in restoration of intracellular ion homeostasis. We propose that the unique and direct ionic regulation of the activities of Ins biosynthesis enzymes represents an efficient biochemical feedback loop for regulation of intracellular physiological ion homeostasis during hyperosmotic stress.

  15. Disruption of Renal Tubular Mitochondrial Quality Control by Myo-Inositol Oxygenase in Diabetic Kidney Disease

    PubMed Central

    Zhan, Ming; Usman, Irtaza M.; Sun, Lin

    2015-01-01

    Diabetic kidney disease (DKD) is associated with oxidative stress and mitochondrial injury. Myo-inositol oxygenase (MIOX), a tubular-specific enzyme, modulates redox imbalance and apoptosis in tubular cells in diabetes, but these mechanisms remain unclear. We investigated the role of MIOX in perturbation of mitochondrial quality control, including mitochondrial dynamics and autophagy/mitophagy, under high-glucose (HG) ambience or a diabetic state. HK-2 or LLC-PK1 cells subjected to HG exhibited an upregulation of MIOX accompanied by mitochondrial fragmentation and depolarization, inhibition of autophagy/mitophagy, and altered expression of mitochondrial dynamic and mitophagic proteins. Furthermore, dysfunctional mitochondria accumulated in the cytoplasm, which coincided with increased reactive oxygen species generation, Bax activation, cytochrome C release, and apoptosis. Overexpression of MIOX in LLC-PK1 cells enhanced the effects of HG, whereas MIOX siRNA or d-glucarate, an inhibitor of MIOX, partially reversed these perturbations. Moreover, decreasing the expression of MIOX under HG ambience increased PTEN-induced putative kinase 1 expression and the dependent mitofusin-2–Parkin interaction. In tubules of diabetic mice, increased MIOX expression and mitochondrial fragmentation and defective autophagy were observed. Dietary supplementation of d-glucarate in diabetic mice decreased MIOX expression, attenuated tubular damage, and improved renal functions. Notably, d-glucarate administration also partially attenuated mitochondrial fragmentation, oxidative stress, and apoptosis and restored autophagy/mitophagy in the tubular cells of these mice. These results suggest a novel mechanism linking MIOX to impaired mitochondrial quality control during tubular injury in the pathogenesis of DKD and suggest d-glucarate as a potential therapeutic agent for the amelioration of DKD. PMID:25270067

  16. High bovine blastocyst development in a static in vitro production system using SOFaa medium supplemented with sodium citrate and myo-inositol with or without serum-proteins.

    PubMed

    Holm, P; Booth, P J; Schmidt, M H; Greve, T; Callesen, H

    1999-09-01

    We describe a bovine embryo culture system that supports repeatable high development in the presence of serum or BSA as well as under defined conditions in the absence of those components. In the first experiment, embryo development in SOF with amino acids (SOFaa), sodium citrate (SOFaac) and myo-inositol (SOFaaci) and with BSA or polyvinyl alcohol (PVA) was compared with that in a M199 granulosa cell co-culture (M199 co-culture). Subsequently, development and cell numbers of blastocysts cultured under defined conditions in SOFaaci with PVA (SOFaaci-PVA), or under undefined conditions in SOFaaci with 5% cow serum (SOFaaci-CS) or M199 co-culture were compared. The repeatability of culture results in SOFaaci-CS was checked by weekly replicates (n = 30) spread over 11 months. The viability of embryos developed in SOFaaci-PVA was estimated by transfer of morphologically good blastocysts (n = 10) to synchronized recipients. In the second experiment, the effect of omitting CS or BSA from IVM and IVM-IVF on subsequent embryo development in SOFaaci-PVA or in SOFaaci-CS was investigated. Blastocyst development in SOFaa-PVA, SOFaac-PVA, SOFaa-BSA and M199 was 16 +/- 3b, 23 +/- 2ab, 30 +/- 8a and 36 +/- 7a%, respectively (Pab < 0.05). Additional inclusion of myoinositol resulted in 42 +/- 1a% blastocysts in SOFaaci-PVA vs 19 +/- 3b% in SOFaac-PVA, 47 +/- 7a% in SOFaac-BSA, and 36 +/- 7a% in M199 co-culture, respectively (Pab < 0.01). In 30 replicates, the average cleavage and blastocyst rates of oocytes in SOFaaci-CS were 87 +/- 4 and 49 +/- 5%, respectively. Five normal calves were produced after transfer of 10 blastocysts developed in defined culture medium (i.e., SOFaaci-PVA). Defined IVM or IVM-IVF (i.e., in absence of CS and BSA) reduced cleavage rates (83 +/- 3 and 55 +/- 3% vs 90 +/- 1% in presence of CS; P < 0.01). Subsequent embryo development in SOFaaci-CS was not affected in either of these defined conditions. However, cleavage and blastocyst rates under completely

  17. Metabolic Studies on Intermediates in the myo-Inositol Oxidation Pathway in Lilium longiflorum Pollen: I. Conversion to Hexoses.

    PubMed

    Rosenfield, C L; Fann, C; Loewus, F A

    1978-01-01

    The myo-inositol oxidation pathway was investigated in regard to its role as a source of carbon for products of hexose monophosphate metabolism in germinated pollen of Lilium longiflorum Thunb., cv. Ace. myo-[2-(14)]Inositol and d-[1-(14)C]glucuronate had similar distributions of radioactivity, contributing about three times more label to polysaccharide-bound glucose than myo-[2-(3)H]inositol. In the course of glucogenesis label from the latter appeared as tritiated water in the medium. This exchange could be enhanced by supplying d-[5R,5S-(3)H]xylose instead of myo-[2-(3)H]inositol. When the former was administered, [(3)H]glucose was the only labeled sugar residue found in polysaccharide products. The soluble constituents of d-[5R,5S-(3)H]xylose-labeled pollen contained no traces of labeled xylose despite massive uptake and utilization.l-[1-(14)C]- and l-[5-(14)C]Arabinose produced similar labeling patterns in germinated pollen including incorporation of arabinosyl units into pollen tube polysaccharides and substantial glucogenesis which led to utilization of arabinose for respiration and further incorporation of labeled glucosyl units into pollen tube polysaccharides.d-[5-(3)H]Galacturonate was rapidly taken up by germinated pollen but slowly utilized, without conversion to other sugars, for incorporation into pollen tube polysaccharides. l-[6-(14)C]Gulonate was not taken up by pollen.Results strongly support a scheme of conversion from myo-inositol to hexose monophosphate and subsequent products of glucose metabolism that involves the myo-inositol oxidation pathway.

  18. The influence of extrusion process on myo-inositol phosphate content and profile in snacks containing rye bran.

    PubMed

    Gambuś, H; Matusz-Mirlak, A; Duliński, R; Ziobro, R; Golachowski, A

    2012-02-01

    The analysis of phytates in extrudates containing rye bran was done by a colorimetric method with the Wade reagent. The changes in profiles of myo-inositol phosphates indicate that, although no isomers with positive physiological functions (such as I(1,4,5)P3, I(1,2,3)P3 or I(1,3,4,5)P4) were formed, the beneficial impact of extrusion is the reduction of phytates, as compared to the raw material. The obtained snacks containing rye bran received acceptable to desirable sensory scores.

  19. Separation of phytic acid and other related inositol phosphates by high-performance ion chromatography and its applications.

    PubMed

    Chen, Qing-Chuan; Li, Betty W

    2003-11-07

    A high-performance anion-exchange chromatographic method was developed for the separation of phytic acid and other inositol phosphates (myo-inositol bis-, tris-, tetrakis-, and pentakisphosphates) with gradient elution and ultraviolet absorbance detection after post-column derivatization. With the acidic eluents, the combination of anion-exchange and ion suppression retention mechanisms led to the separation of 35 inositol phosphates (excluding enantiomers) into 27 peaks for the first time, and the retention behaviors of all myo-inositol bis- to hexakisphosphate isomers were studied. The whole separation procedure was completed within 65 min. Based on the investigations of nonenzymatic hydrolysis of phytic acid under different conditions by using this method, an in-house reference standard solution was produced, which can be used for method development. In addition, by applying this method to in vitro kinetic studies, at least one new enzymatic hydrolysis pathway of phytic acid was found, and one rule of enzymatic dephosphorylation of inositol phosphates (position effect) was proposed and another one (neighboring effect) was confirmed. The principle of the proposed identification approach for several inositol phosphate isomers based on hydrolysis products study will be applicable to other natural products analysis, for which standards are very expensive or not available.

  20. Myo-inositol changes precede amyloid pathology and relate to APOE genotype in Alzheimer disease

    PubMed Central

    Sundgren, Pia C.; Strandberg, Olof; Zetterberg, Henrik; Minthon, Lennart; Blennow, Kaj; Wahlund, Lars-Olof; Westman, Eric

    2016-01-01

    Objective: We aimed to test whether in vivo levels of magnetic resonance spectroscopy (MRS) metabolites myo-inositol (mI), N-acetylaspartate (NAA), and choline are abnormal already during preclinical Alzheimer disease (AD), relating these changes to amyloid or tau pathology, and functional connectivity. Methods: In this cross-sectional multicenter study (a subset of the prospective Swedish BioFINDER study), we included 4 groups, representing the different stages of predementia AD: (1) cognitively healthy elderly with normal CSF β-amyloid 42 (Aβ42), (2) cognitively healthy elderly with abnormal CSF Aβ42, (3) patients with subjective cognitive decline and abnormal CSF Aβ42, (4) patients with mild cognitive decline and abnormal CSF Aβ42 (Ntotal = 352). Spectroscopic markers measured in the posterior cingulate/precuneus were considered alongside known disease biomarkers: CSF Aβ42, phosphorylated tau, total tau, [18F]-flutemetamol PET, f-MRI, and the genetic risk factor APOE. Results: Amyloid-positive cognitively healthy participants showed a significant increase in mI/creatine and mI/NAA levels compared to amyloid-negative healthy elderly (p < 0.05). In amyloid-positive healthy elderly, mI/creatine and mI/NAA correlated with cortical retention of [18F] flutemetamol tracer ( = 0.44, p = 0.02 and = 0.51, p = 0.01, respectively). Healthy elderly APOE ε4 carriers with normal CSF Aβ42 levels had significantly higher mI/creatine levels (p < 0.001) than ε4 noncarriers. Finally, elevated mI/creatine was associated with decreased functional connectivity within the default mode network (rpearson = −0.16, p = 0.02), independently of amyloid pathology. Conclusions: mI levels are elevated already at asymptomatic stages of AD. Moreover, mI/creatine concentrations were increased in healthy APOE ε4 carriers with normal CSF Aβ42 levels, suggesting that mI levels may reveal regional brain consequences of APOE ε4 before detectable amyloid pathology. PMID:27164711

  1. A limitation of the continuous spectrophotometric assay for the measurement of myo-inositol-1-phosphate synthase activity.

    PubMed

    Huang, Xinyi; Hernick, Marcy

    2011-10-15

    Myo-inositol-1-phosphate synthase (MIPS) catalyzes the conversion of glucose-6-phosphate to myo-inositol-1-phosphate. The reaction catalyzed by MIPS is the first step in the biosynthesis of inositol and inositol-containing molecules that serve important roles in both eukaryotes and prokaryotes. Consequently, MIPS is a target for the development of therapeutic agents for the treatment of infectious diseases and bipolar disorder. We recently reported a continuous spectrophotometric method for measuring MIPS activity using a coupled assay that allows the rapid characterization of MIPS in a multiwell plate format. Here we validate the continuous assay as a high-throughput alternative for measuring MIPS activity and report on one limitation of this assay-the inability to examine the effect of divalent metal ions (at high concentrations) on MIPS activity. In addition, we demonstrate that the activity of MIPS from Arabidopsis thaliana is moderately enhanced by the addition Mg(2+) and is not enhanced by other divalent metal ions (Zn(2+) and Mn(2+)), consistent with what has been observed for other eukaryotic MIPS enzymes. Our findings suggest that the continuous assay is better suited for characterizing eukaryotic MIPS enzymes that require monovalent cations as cofactors than for characterizing bacterial or archeal MIPS enzymes that require divalent metal ions as cofactors.

  2. Isolation and characterization of a low phytic acid rice mutant reveals a mutation in the rice orthologue of maize MIK.

    PubMed

    Kim, S I; Andaya, C B; Newman, J W; Goyal, S S; Tai, T H

    2008-11-01

    Using a forward genetics approach, we isolated two independent low phytic acid (lpa) rice mutants, N15-186 and N15-375. Both mutants are caused by single gene, recessive non-lethal mutations, which result in approximately 75% (N15-186) and 43% (N15-375) reductions in seed phytic acid (inositol hexakisphosphate). High-performance liquid chromatography and GC-MS analysis of seed extracts from N15-186 indicated that, in addition to phytic acid, inositol monophosphate was significantly reduced whereas inorganic phosphorus and myo-inositol were greatly increased when compared with wild-type. The changes observed in N15-186 resemble those previously described for the maize lpa3 mutant. Analysis of N15-375 revealed changes similar to those observed in previously characterized rice lpa1 mutants (i.e. significant reduction in phytic acid and corresponding increase in inorganic phosphorus with little or no change in inositol phosphate intermediates or myo-inositol). Further genetic analysis of the N15-186 mutant indicated that the mutation, designated lpa N15-186, was located in a region on chromosome 3 between the microsatellite markers RM15875 and RM15907. The rice orthologue of maize lpa3, which encodes a myo-inositol kinase, is in this interval. Sequence analysis of the N15-186 allele of this orthologue (Os03g52760) revealed a single base pair change (C/G to T/A) in the first exon of the gene, which results in a nonsense mutation. Our results indicate that lpa N15-186 is a mutant allele of the rice myo-inositol kinase (OsMIK) gene. Identification and characterization of lpa mutants, such as N15-186, will facilitate studies on the regulation of phytic acid biosynthesis and accumulation and help address questions concerning the contribution of the inositol lipid-dependent and independent biosynthetic pathways to the production of seed phytic acid.

  3. Effect of co-solutes and process variables on crystallinity and the crystal form of freeze-dried myo-inositol.

    PubMed

    Izutsu, Ken-Ichi; Kusano, Riho; Arai, Ryoko; Yoshida, Hiroyuki; Ito, Masataka; Shibata, Hiroko; Sugano, Kiyohiko; Goda, Yukihiro; Terada, Katsuhide

    2016-07-25

    The purpose of this study was to elucidate how co-solutes affect the crystallization of small solute molecules during freeze-drying and subsequent storage. Crystallization profiles of myo-inositol and its mixture with dextran 40k in frozen solutions and dried solids were assessed by thermal analysis (DSC), powder-X-ray diffraction, and simultaneous DSC and PXRD analysis. Higher mass ratios of dextran maintained myo-inositol in the non-crystalline mixture state, in frozen solutions, during freeze-drying process, and exposure of dried solids to higher temperatures. Co-lyophilization with a lower mass ratio of dextran resulted in solids containing a variety of myo-inositol crystal forms and crystallinity depending on the composition and thermal history of the process. Heating of some inositol-rich amorphous solids showed crystallization of myo-inositol in the metastable form and its transition to stable form before melting. Heat-treatment of inositol-rich frozen solutions resulted in high crystallinity stable-form inositol solids, leaving dextran in the amorphous state. Sufficient direct molecular interactions (e.g., hydrogen bonding) should explain the stability of dextran-rich amorphous solids. Optimizing solute composition and processes should be a potent way to control crystal form and crystallinity of components in freeze-dried formulations.

  4. Arabidopsis FHY3 and FAR1 Regulate Light-Induced myo-Inositol Biosynthesis and Oxidative Stress Responses by Transcriptional Activation of MIPS1.

    PubMed

    Ma, Lin; Tian, Tian; Lin, Rongcheng; Deng, Xing-Wang; Wang, Haiyang; Li, Gang

    2016-04-04

    myo-Inositol-1-phosphate synthase (MIPS) catalyzes the limiting step of inositol biosynthesis and has crucial roles in plant growth and development. In response to stress, the transcription of MIPS1 is induced and the biosynthesis of inositol or inositol derivatives is promoted by unknown mechanisms. Here, we found that the light signaling protein FAR-RED ELONGATED HYPOCOTYL3 (FHY3) and its homolog FAR-RED IMPAIRED RESPONSE1 (FAR1) regulate light-induced inositol biosynthesis and oxidative stress responses by activating the transcription of MIPS1. Disruption of FHY3 and FAR1 caused light-induced cell death after dark-light transition, precocious leaf senescence, and increased sensitivity to oxidative stress. Reduction of salicylic acid (SA) accumulation by overexpression of SALICYLIC ACID 3-HYDROXYLASE largely suppressed the cell death phenotype of fhy3 far1 mutant plants, suggesting that FHY3- and FAR1-mediated cell death is dependent on SA. Furthermore, comparative analysis of chromatin immunoprecipitation sequencing and microarray results revealed that FHY3 and FAR1 directly target both MIPS1 and MIPS2. The fhy3 far1 mutant plants showed severely decreased MIPS1/2 transcript levels and reduced inositol levels. Conversely, constitutive expression of MIPS1 partially rescued the inositol contents, caused reduced transcript levels of SA-biosynthesis genes, and prevented oxidative stress in fhy3 far1. Taken together, our results indicate that the light signaling proteins FHY3 and FAR1 directly bind the promoter of MIPS1 to activate its expression and thereby promote inositol biosynthesis to prevent light-induced oxidative stress and SA-dependent cell death.

  5. Determination of mannitol sorbitol and myo-inositol in olive tree roots and rhizospheric soil by gas chromatography and effect of severe drought conditions on their profiles.

    PubMed

    Mechri, Beligh; Tekaya, Meriem; Cheheb, Hechmi; Hammami, Mohamed

    2015-01-01

    This study reports a method for the analysis of mannitol, sorbitol and myo-inositol in olive tree roots and rhizospheric soil with gas chromatography. The analytical method consists of extraction with a mixture of dichloromethane:methanol (2:1, v/v) for soil samples and a mixture of ethanol:water (80:20) for root samples, silylation using pyridine, hexamethyldisilazane (HMDS) and trimethylchlorosilane (TMCS). The recovery of mannitol sorbitol and myo-inositol (for extraction and analysis in dichloromethane:methanol and ethanol:water) was acceptable and ranged from 100.3 to 114.7%. The time of analysis was <24 min. Among identified polyols extracted from rhizosphere and roots of olive plants, mannitol was the major compound. A marked increase in mannitol content occurred in rhizosphere and roots of water-stressed plants, suggesting a much broader role of mannitol in stress response based on its ability to act as a compatible solute.

  6. Identification and Functional Implications of Sodium/Myo-inositol Cotransporter 1 in Pancreatic Beta-cells and Type 2 Diabetes Mellitus.

    PubMed

    Ting Li, Stephen Yu; Wai Cheng, Sam Tsz; Zhang, Dan; Leung, Po Sing

    2017-02-15

    Myo-inositol (MI), the precursor of the second messenger phosphoinositide (PI), mediates multiple cellular events. Rat islets exhibit active transport of MI, though the mechanism involved remains elusive. Here, we report, for the first time, the expression of sodium/myo-inositol cotransporter 1 (SMIT1) in rat islets and specifically, β-cells. Genetic or pharmacological inhibition of SMIT impaired glucose-stimulated insulin secretion by INS-1E cells, probably via down-regulation of PI signaling. Additionally, we found that SMIT1 expression in INS-1E cells and isolated islets was augmented by acute high-glucose exposure and reduced in chronic hyperglycemia conditions. In corroboration, chronic MI treatment improved the disease phenotypes of diabetic rats and islets. Based on our results, we postulate that the MI transporter SMIT1 is required to maintain a stable PI pool in β-cells in order that PI remains available despite its rapid turnover.

  7. Detection of the myo-inositol 4.06-ppm resonance by selective J rewinding: application to human prefrontal cortex in vivo.

    PubMed

    Choi, Changho; Ogilvie, Catherine J; Malykhin, Nikolai; Ngo, Jennifer T V; Hartfeil, Misha A W; Coupland, Nicholas J

    2005-12-01

    A new proton NMR single-voxel spectral editing strategy for the rapid measurement of myo-inositol in human brain is proposed. The spectral editing detects the 4.06-ppm, weakly coupled resonance by means of selective J rewinding. An 84.6-ms-long quadruple-resonance selective 180 degrees radiofrequency pulse, implemented within an adiabatic-refocused localization sequence, induces an in-phase triplet at 4.06 ppm, while eliminating the contribution from creatine, phosphorylethanolamine, lactate, and serine in this spectral region. The myo-inositol concentration in human prefrontal cortex is estimated to be 5.7 +/- 0.9 mumol/g (mean +/- SD, n = 7), with reference to NAA at 10 micromol/g.

  8. A Functional myo-Inositol Dehydrogenase Gene Is Required for Efficient Nitrogen Fixation and Competitiveness of Sinorhizobium fredii USDA191 To Nodulate Soybean (Glycine max [L.] Merr.)

    PubMed Central

    Jiang, Guoqiao; Krishnan, Ammulu Hari; Kim, Yong-Woong; Wacek, Thomas J.; Krishnan, Hari B.

    2001-01-01

    Inositol derivative compounds provide a nutrient source for soil bacteria that possess the ability to degrade such compounds. Rhizobium strains that are capable of utilizing certain inositol derivatives are better colonizers of their host plants. We have cloned and determined the nucleotide sequence of the myo-inositol dehydrogenase gene (idhA) of Sinorhizobium fredii USDA191, the first enzyme responsible for inositol catabolism. The deduced IdhA protein has a molecular mass of 34,648 Da and shows significant sequence similarity with protein sequences of Sinorhizobium meliloti IdhA and MocA; Bacillus subtilis IolG, YrbE, and YucG; and Streptomyces griseus StrI. S. fredii USDA191 idhA mutants revealed no detectable myo-inositol dehydrogenase activity and failed to grow on myo-inositol as a sole carbon source. Northern blot analysis and idhA-lacZ fusion expression studies indicate that idhA is inducible by myo-inositol. S. fredii USDA191 idhA mutant was drastically affected in its ability to reduce nitrogen and revealed deteriorating bacteroids inside the nodules. The number of bacteria recovered from such nodules was about threefold lower than the number of bacteria isolated from nodules initiated by S. fredii USDA191. In addition, the idhA mutant was also severely affected in its ability to compete with the wild-type strain in nodulating soybean. Under competitive conditions, nodules induced on soybean roots were predominantly occupied by the parent strain, even when the idhA mutant was applied at a 10-fold numerical advantage. Thus, we conclude that a functional idhA gene is required for efficient nitrogen fixation and for competitive nodulation of soybeans by S. fredii USDA191. PMID:11274120

  9. Potentiometric and spectroscopic study of the interaction of 3d transition metal ions with inositol hexakisphosphate

    NASA Astrophysics Data System (ADS)

    Veiga, Nicolás; Macho, Israel; Gómez, Kerman; González, Gabriel; Kremer, Carlos; Torres, Julia

    2015-10-01

    Among myo-inositol phosphates, the most abundant in nature is the myo-inositol hexakisphosphate, InsP6. Although it is known to be vital to cell functioning, the biochemical research into its metabolism needs chemical and structural analysis of all the protonation, complexation and precipitation processes that it undergoes in the biological media. In view of its high negative charge at physiological level, our group has been leading a thorough research into the InsP6 chemical and structural behavior in the presence of the alkali and alkaline earth metal ions essential for life. The aim of this article is to extend these studies, dealing with the chemical and structural features of the InsP6 interaction with biologically relevant 3d transition metal ions (Fe(II), Fe(III), Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)), in a non-interacting medium and under simulated physiological conditions. The metal-complex stability constants were determined by potentiometry, showing under ligand-excess conditions the formation of mononuclear species in different protonation states. Under metal ion excess, polymetallic species were detected for Fe(II), Fe(III), Zn(II) and Cu(II). Additionally, the 31P NMR and UV-vis spectroscopic studies provided interesting structural aspects of the strong metal ion-InsP6 interaction.

  10. In Vitro Antioxidant Treatment of Semen Samples in Assisted Reproductive Technology: Effects of Myo-Inositol on Nemaspermic Parameters

    PubMed Central

    Papale, Palma; Della Ragione, Antonietta; Quaranta, Giuseppa; Russo, Giovanni; Russo, Sabatino

    2016-01-01

    Male infertility and the poor quality of sperm seem to be influenced by oxidative stress. In particular, the reactive oxygen species (ROS) mainly produced by morphologically altered spermatozoa affect sperm motility, morphology, and integrity. The aim of this study was to evaluate the efficacy of Myo-Inositol (Myo-Ins) on a number of parameters such as viscosity and total and progressive motility of spermatozoa, in order to better validate its possible practical application in vitro, in order to improve the capacitation protocols commonly used in Assisted Reproductive Technology (ART). A total of 100 fresh and 25 thawed semen samples were analyzed in vitro prior to and after addition of Myo-Ins. Treatment of samples with Myo-Ins showed an increase in the sperm total and progressive motility in both fresh and thawed samples. Furthermore, Myo-Ins proved to be well tolerated by spermatozoa in vitro, demonstrating that it can be efficiently and safely used as antioxidant in the laboratory practice and for preparation of semen samples in ART. PMID:27672392

  11. Functional myo-inositol catabolic genes of Bacillus subtilis Natto are involved in depletion of pinitol in Natto (fermented soybean).

    PubMed

    Morinaga, Tetsuro; Yamaguchi, Masanori; Makino, Yuki; Nanamiya, Hideaki; Takahashi, Kiwamu; Yoshikawa, Hirofumi; Kawamura, Fujio; Ashida, Hitoshi; Yoshida, Ken-Ichi

    2006-08-01

    Soybeans are rich in pinitol (PI; 3-O-methyl-D-chiro-inositol), which improves health by treating conditions associated with insulin resistance, such as diabetes mellitus and obesity. Natto is a food made from soybeans fermented by strains of Bacillus subtilis natto. In the chromosome of natto strain OK2, there is a putative promoter region almost identical to the iol promoter for myo-inositol (MI) catabolic genes of B. subtilis 168. In the presence of MI, the putative iol promoter functioned to induce inositol dehydrogenase, the enzyme for the first-step reaction in the MI catabolic pathway. PI also induced inositol dehydrogenase and the promoter was indispensable for the utilization of PI as well as MI, suggesting that PI might be an alternative carbon source metabolized in a way involving the MI catabolic genes. Natto fermentation studies have revealed that the parental natto strain consumed PI while a mutant defective in the iol promoter did not do so at all. These results suggest that inactivating the MI catabolic genes might prevent PI consumption, retaining it in natto for enrichment of possible health-promoting properties.

  12. Anion-exchange high-performance liquid chromatography with post-column detection for the analysis of phytic acid and other inositol phosphates

    NASA Technical Reports Server (NTRS)

    Rounds, M. A.; Nielsen, S. S.; Mitchell, C. A. (Principal Investigator)

    1993-01-01

    The use of gradient anion-exchange HPLC, with a simple post-column detection system, is described for the separation of myo-inositol phosphates, including "phytic acid" (myo-inositol hexaphosphate). Hexa-, penta-, tetra-, tri- and diphosphate members of this homologous series are clearly resolved within 30 min. This method should facilitate analysis and quantitation of "phytic acid" and other inositol phosphates in plant, food, and soil samples.

  13. Anion-exchange high-performance liquid chromatography with post-column detection for the analysis of phytic acid and other inositol phosphates.

    PubMed

    Rounds, M A; Nielsen, S S

    1993-10-29

    The use of gradient anion-exchange HPLC, with a simple post-column detection system, is described for the separation of myo-inositol phosphates, including "phytic acid" (myo-inositol hexaphosphate). Hexa-, penta-, tetra-, tri- and diphosphate members of this homologous series are clearly resolved within 30 min. This method should facilitate analysis and quantitation of "phytic acid" and other inositol phosphates in plant, food, and soil samples.

  14. Biochemical characterisation of extracellular phytase (myo-inositol hexakisphosphate phosphohydrolase) from a hyper-producing strain of Aspergillus niger van Teighem.

    PubMed

    Vats, Purva; Banerjee, U C

    2005-04-01

    Aspergillus niger van Teighem, isolated in our laboratory from samples of rotten wood logs, produced extracellular phytase having a high specific activity of 22,592 units (mg protein)-1 . The enzyme was purified to near homogeneity using ion-exchange and gel-filtration chromatography. The molecular properties of the purified enzyme suggested the native phytase to be oligomeric, with a molecular weight of 353 kDa, the monomer being 66 kDa. The purified enzyme exhibited maximum activity at pH 2.5 and 52-55 degrees C. The enzyme retained 97% activity after a 24-h incubation at 55 degrees C in the presence of 10 mM glycine, while 87% activity was retained when no thermoprotectant was added. Phytase activity was not affected by most metal ions, inhibitors and organic solvents. Non-ionic and cationic detergents (0.1-5%) stabilise the enzyme, while the anionic detergent (SDS), even at a 0.1% level, severely inhibited enzyme activity. The chaotropic agents guanidinium hydrochloride, urea, and potassium iodide (0.5-8 M), significantly affected phytase activity. The maximum hydrolysis rate (Vmax) and apparent Michaelis-Menten constant (Km) were 1,074 IU/mL and 606 microM, respectively, with a catalytic turnover number of 3x10(5) s-1 and catalytic efficiency of 3.69x10(8) M-1 s-1.

  15. Modulation of basal nitric oxide-dependent cyclic-GMP production by ambient glucose, myo-inositol, and protein kinase C in SH-SY5Y human neuroblastoma cells.

    PubMed Central

    Shindo, H; Thomas, T P; Larkin, D D; Karihaloo, A K; Inada, H; Onaya, T; Stevens, M J; Greene, D A

    1996-01-01

    Defective tissue perfusion and nitric oxide production and altered myo-inositol metabolism and protein kinase C activation have been invoked in the pathogenesis of diabetic complications including neuropathy. The precise cellular compartmentalization and mechanistic interrelationships of these abnormalities remain obscure, and nitric oxide possesses both neurotransmitter and vasodilator activity. Therefore the effects of ambient glucose and myo-inositol on nitric oxide-dependent cGMP production and protein kinase C activity were studied in SH-SY5Y human neuroblastoma cells, a cell culture model for peripheral cholinergic neurons. D-Glucose lowered cellular myo-inositol content, phosphatidylinositol synthesis, and phosphorylation of an endogenous protein kinase C substrate, and specifically reduced nitric oxide-dependent cGMP production a time- and dose-dependent manner with an apparent IC50 of approximately 30 mM. The near maximal decrease in cGMP induced by 50 mM D-glucose was corrected by the addition of protein kinase C agonists or 500 microM myo-inositol to the culture medium, and was reproduced by protein kinase C inhibition or downregulation, or by myo-inositol deficient medium. Sodium nitroprusside increased cGMP in a dose-dependent fashion, with low concentrations (1 microM) counteracting the effects of 50 mM D-glucose or protein kinase C inhibition. The demonstration that elevated D-glucose diminishes basal nitric oxide-dependent cGMP production by myo-inositol depletion and protein kinase C inhibition in peripheral cholinergic neurons provides a potential metabolic basis for impaired nitric oxide production, nerve blood flow, and nerve impulse conduction in diabetes. PMID:8609230

  16. Differentially expressed myo-inositol monophosphatase gene (CaIMP) in chickpea (Cicer arietinum L.) encodes a lithium-sensitive phosphatase enzyme with broad substrate specificity and improves seed germination and seedling growth under abiotic stresses.

    PubMed

    Saxena, Saurabh C; Salvi, Prafull; Kaur, Harmeet; Verma, Pooja; Petla, Bhanu Prakash; Rao, Venkateswara; Kamble, Nitin; Majee, Manoj

    2013-12-01

    myo-Inositol monophosphatase (IMP) is an essential enzyme in the myo-inositol metabolic pathway where it primarily dephosphorylates myo-inositol 1-phosphate to maintain the cellular inositol pool which is important for many metabolic and signalling pathways in plants. The stress-induced increased accumulation of inositol has been reported in a few plants including chickpea; however, the role and regulation of IMP is not well defined in response to stress. In this work, it has been shown that IMP activity is distributed in all organs in chickpea and was noticeably enhanced during environmental stresses. Subsequently, using degenerate oligonucleotides and RACE strategy, a full-length IMP cDNA (CaIMP) was cloned and sequenced. Biochemical study revealed that CaIMP encodes a lithium-sensitive phosphatase enzyme with broad substrate specificity, although maximum activity was observed with the myo-inositol 1-phosphate and l-galactose 1-phosphate substrates. Transcript analysis revealed that CaIMP is differentially expressed and regulated in different organs, stresses and phytohormones. Complementation analysis in Arabidopsis further confirmed the role of CaIMP in l-galactose 1-phosphate and myo-inositol 1-phosphate hydrolysis and its participation in myo-inositol and ascorbate biosynthesis. Moreover, Arabidopsis transgenic plants over-expressing CaIMP exhibited improved tolerance to stress during seed germination and seedling growth, while the VTC4/IMP loss-of-function mutants exhibited sensitivity to stress. Collectively, CaIMP links various metabolic pathways and plays an important role in improving seed germination and seedling growth, particularly under stressful environments.

  17. Some Oxygen-18 Studies on the Mechanism of Myo-inositol Oxygenase.

    DTIC Science & Technology

    1980-08-01

    Reductase 1. Background In 1957, A. L. Lehninger reported that a TPNH-specific dehydrogenase which reduces D-glucuronic acid is present in rat kidney...Swan, J., unpublished results. 13. Grollman, A. P., and A. L. Lehninger , Arch. Biochem. Biophys., 69, 458 (1957). 14. Bosron, W. F., and R. L

  18. Defining the minimal structural requirements for partial agonism at the type I myo-inositol 1,4,5-trisphosphate receptor.

    PubMed

    Wilcox, R A; Fauq, A; Kozikowski, A P; Nahorski, S R

    1997-02-03

    The novel synthetic analogues D-3-fluoro-myo-inositol 1,5-bisphosphate-4-phosphorothioate, [3F-Ins(1,5)P2-4PS], D-3-fluoro-myo-inositol 1,4-bisphosphate-5-phosphorothioate [3F-Ins(1,4)P2-5PS], and D-3-fluoro-myo-inositol 1-phosphate-4,5-bisphosphorothioate [3F-Ins(1)P-(4,5)PS2] were utilised to define the structure-activity relationships which could produce partial agonism at the Ca2+ mobilising myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] receptor. Based on prior structure-activity data we hypothesised that the minimal structural requirements for lns(1,4,5)P3 receptor partial agonism, were phosphorothioate substitution of the crucial vicinal 4,5-bisphosphate pair accompanied by another structural perturbation, such fluorination of 3-position of the myo-inositol ring. All the analogues fully displaced [3H]Ins(1,4,5)P3 from a single Ins(1,4,5)P3 binding site in pig cerebellar membranes [3F-Ins(1,5)P2-4PS (1C50 = 26 nM), 3F-Ins(1,4)P2-5PS (IC50 = 80 nM) and 3F-Ins(1)P-(4,5)PS2 (IC50 = 109 nM) cf. Ins(1,4,5)P3 (IC50 = 11 nM)]. In contrast, 3F-Ins(1,5)P2-4PS (IC50 = 424 nM) and 3F-Ins(1,4)P2-5PS (IC50 = 3579 nM) were weak full agonists at the Ca2+ mobilising Ins(1,4,5)P3 receptor of permeabilised SH-SY5Y neuroblastoma cells, being respectively 4- and 36-fold less potent than Ins(1,4,5)P3 (EC50 = 99 nM). While 3F-Ins(1)P-(4,5)PS2 (EC50 = 11345 nM) was a partial agonist releasing only 64.3 +/- 1.9% of the Ins(1,4,5)P3-sensitive intracellular Ca2+ pools. 3F-Ins(1)P-(4,5)PS2 was unique among the Ins(1,4,5)P3 receptor partial agonists so far identified in having a relatively high affinity for the Ins(1,4,5)P3 binding site, accompanied by a significant loss of intrinsic activity for Ca2+ mobilisation. This improved affinity was probably due to the retention of the 1-position phosphate, which enhances interaction with the Ins-(1,4,5)P3 receptor. 3F-Ins(1)P-(4,5)PS2 may be an important lead compound for the development of efficient Ins(1,4,5)P3 receptor antagonists.

  19. Myo-Inositol trisphosphate mobilizes calcium from fusogenic carrot (Daucus carota L. ) protoplasts

    SciTech Connect

    Rincon, M.; Boss, W.F.

    1987-02-01

    To determine whether or not inositol trisphosphate (IP/sub 3/) mobilizes calcium in higher plant cells; they investigated the effect of IP/sub 3/ on Ca/sup 2 +/ fluxes in fusogenic carrot (Daucus carota L.) protoplasts. The protoplasts were incubated in /sup 45/Ca/sup 2 +/-containing medium and the /sup 45/Ca/sup 2 +/ associated with the protoplasts was monitored with time. Addition of IP/sub 3/ (20 micromolar) caused a 17% net loss of the accumulated /sup 45/Ca/sup 2 +/ within 4 minutes. There was a reuptake of /sup 45/Ca/sup 2 +/ and the protoplasts recovered to their initial value by 10 minutes. Phytic acid (IP/sub 6/), also stimulated /sup 45/Ca/sup 2 +/ efflux from the protoplasts. Both the IP/sub 3/- and the IP/sub 6/-induced /sup 45/Ca/sup 2 +/ efflux were inhibited by the calmodulin antagonist, trifluoperazine.

  20. Metabolic Studies on Intermediates in the myo-Inositol Oxidation Pathway in Lilium longiflorum Pollen: II. Evidence for the Participation of Uridine Diphosphoxylose and Free Xylose as Intermediates.

    PubMed

    Rosenfield, C L; Loewus, F A

    1978-01-01

    myo-Inositol-linked glucogenesis in germinated lily (Lilium longiflorum Thunb., cv. Ace) pollen was investigated by studying the effects of added l-arabinose or d-xylose on metabolism of myo-[2-(3)H]inositol and by determining the distribution of radioisotope in pentosyl and hexosyl residues of polysaccharides from pollen labeled with myo-[2-(14)C]inositol, myo-[2-(3)H]inositol, l-[5-(14)C]arabinose, and d-[5R,5S-(3)H]xylose.myo-[2-(14)C]Inositol and l-[5-(14)C]arabinose produced labeled glucose with similar patterns of distribution of (14)C, 35% in C1, and 55% in C6. Arabinosyl units were labeled exclusively in C5. Incorporation of (3)H into arabinosyl and xylosyl units in pollen labeled with myo-[2-(3)H]inositol was repressed when unlabeled l-arabinose was included in the germination medium and a related (3)H exchange with water was stimulated. Results are consistent with a process of glucogenesis in which the myo-inositol oxidation pathway furnishes UDP-d-xylose as a key intermediate for conversion to hexose via free d-xylose and the pentose phosphate pathway.Additional evidence for this process was obtained from pollen labeled with d-[5R,5S-(3)H]xylose or myo-[2-(3)H]inositol which produces d-[5R-(3)H]xylose. Glucosyl units from polysaccharides in the former had 11% of the (3)H in C1 and 78% in C6 while glucosyl units in the latter had only 4% in C1 and 78% in C6. Stereochemical considerations involving selective exchange with water of prochiral-R (3)H in C1 of fructose-6-P during conversion to glucose provide explanation for observed differences in the metabolism of these 5-labeled xyloses.Incorporation of (3)H from myo-[2-(3)H]inositol into arabinosyl and xylosyl units of pollen polysaccharides was unaffected by the presence of unlabeled d-xylose in the medium. Exchange of (3)H with water was greatly affected, decreasing from a value of 21% exchange in the absence of unlabeled d-xylose to 5% in the presence of 6.7 mmd-xylose.d-Xylose was rapidly utilized for

  1. Engineering crystals that facilitate the acyl-transfer reaction: insight from a comparison of the crystal structures of myo-inositol-1,3,5-orthoformate-derived benzoates and carbonates.

    PubMed

    Tamboli, Majid I; Krishanaswamy, Shobhana; Gonnade, Rajesh G; Shashidhar, Mysore S

    2016-11-01

    Minor variations in the molecular structure of constituent molecules of reactive crystals often yield crystals with significantly different properties due to altered modes of molecular association in the solid state. Hence, these studies could provide a better understanding of the complex chemical processes occurring in the crystalline state. However, reactions that proceed efficiently in molecular crystals are only a small fraction of the reactions that are known to proceed (with comparable efficiency) in the solution state. Hence, for consistent progress in this area of research, investigation of newer reactive molecular crystals which support different kinds of reactions and their related systems is essential. The crystal structures and acyl-transfer reactivity of a myo-inositol-1,3,5-orthoformate-derived dibenzoate and its carbonate (4-O-benzoyl-2-O-phenoxycarbonyl-myo-inositol 1,3,5-orthoformate, C21H18O9) and thiocarbonate (4-O-benzoyl-2-O-phenoxythiocarbonyl-myo-inositol 1,3,5-orthoformate, C21H18O8S) analogs are compared with the aim of understanding the relationship between crystal structure and acyl-transfer reactivity. Insertion of an O atom in the acyl (or thioacyl) group of an ester gives the corresponding carbonate (or thiocarbonate). This seemingly minor change in molecular structure results in a considerable change in the packing of the molecules in the crystals of myo-inositol-1,3,5-orthoformate-derived benzoates and the corresponding carbonates. These differences result in a lack of intermolecular acyl-transfer reactivity in crystals of myo-inositol-1,3,5-orthoformate-derived carbonates. Hence, this study illustrates the sensitivity of the relative orientation of molecules, their packing and ensuing changes in the reactivity of resulting crystals to minor changes in molecular structure.

  2. The Structure of the L-myo-inositol-1-phosphate Synthase-NAD[superscript +]-2-deoxy-D-glucitol 6-(E)-Vinylhomophosphonate Complex Demands a Revision of the Enzyme Mechanism

    SciTech Connect

    Jin, Xiangshu; Foley, Kathleen M.; Geiger, James H.

    2010-11-16

    1l-myo-inositol 1-phosphate (MIP) synthase catalyzes the conversion of D-glucose 6-phosphate to 1l-myo-inositol 1-phosphate, the first and rate-limiting step in the biosynthesis of all inositol-containing compounds. It involves an oxidation, enolization, intramolecular aldol cyclization, and reduction. Here we present the structure of MIP synthase in complex with NAD{sup +} and a high-affinity inhibitor, 2-deoxy-D-glucitol 6-(E)-vinylhomophosphonate. This structure reveals interactions between the enzyme active site residues and the inhibitor that are significantly different from that proposed for 2-deoxy-D-glucitol 6-phosphate in the previously published structure of MIP synthase-NAD{sup +}-2-deoxy-D-glucitol 6-phosphate. There are several other conformational changes in NAD{sup +} and the enzyme active site as well. Based on the new structural data, we propose a new and completely different mechanism for MIP synthase.

  3. A Novel and Rapid Colorimetric Method for Measuring Total Phosphorus and Phytic Acid in Foods and Animal Feeds.

    PubMed

    2016-04-08

    Phytic acid, or myo-inositol hexakisphosphate, is the primary source of inositol and storage phosphorus in plant seeds and has considerable nutritional importance. In this form, phosphorus is unavailable for absorption by monogastric animals, and the strong chelating characteristic of phytic acid reduces the bioavailability of multivalent minerals such as iron, zinc, and calcium. Currently, there is no simple quantitative method for phytic acid; existing methods are complex, and the most commonly accepted method, AOAC Official Method (SM) 986.11, has limitations. The aim of this work was to develop and validate a simple, high-throughput method for the measurement of total phosphorus and phytic acid in foods and animal feeds. The method described here involves acid extraction of phytic acid, followed by dephosphorylation with phytase and alkaline phosphatase. The phosphate released from phytic acid is measured using a modified colorimetric molybdenum blue assay and calculated as total phosphorus or phytic acid content of the original sample. The method was validated to a maximum linearity of 3.0 g phytic acid/100 g sample. Accuracy ranged from 98 to 105% using pure phytic acid and from 97 to 115% for spiked samples. Repeatability ranged from 0.81 to 2.32%, and intermediate precision was 2.27%.

  4. Certain Malvaceae Plants Have a Unique Accumulation of myo-Inositol 1,2,4,5,6-Pentakisphosphate

    PubMed Central

    Phillippy, Brian Q.; Perera, Imara Y.; Donahue, Janet L.; Gillaspy, Glenda E.

    2015-01-01

    Methods used to quantify inositol phosphates in seeds lack the sensitivity and specificity necessary to accurately detect the lower concentrations of these compounds contained in the leaves of many plants. In order to measure inositol hexakisphosphate (InsP6) and inositol pentakisphosphate (InsP5) levels in leaves of different plants, a method was developed to concentrate and pre-purify these compounds prior to analysis. Inositol phosphates were extracted from leaves with diluted HCl and concentrated on small anion exchange columns. Reversed-phase solid phase extraction cartridges were used to remove compounds that give peaks that sometimes interfere during HPLC. The method permitted the determination of InsP6 and InsP5 concentrations in leaves as low as 10 µM and 2 µM, respectively. Most plants analyzed contained a high ratio of InsP6 to InsP5. In contrast, certain members of the Malvaceae family, such as cotton (Gossypium) and some hibiscus (Hibiscus) species, had a preponderance of InsP5. Radiolabeling of cotton seedlings also showed increased amounts of InsP5 relative to InsP6. Why some Malvaceae species exhibit a reversal of the typical ratios of these inositol phosphates is an intriguing question for future research. PMID:27135328

  5. Effect of Treating Streptozotocin-Induced Diabetic Rats With Sorbinil, Myo-Inositol or Aminoguanidine on Endoneurial Blood Flow, Motor Nerve Conduction Velocity and Vascular Function of Epineurial Arterioles of the Sciatic Nerve

    PubMed Central

    Coppey, Lawrence J.; Gellett, Jill S.; Davidson, Eric P.; Dunlap, Joyce A.

    2002-01-01

    Previously we have demonstrated that diabetes causes impairment in vascular function of epineurial vessels, which precedes the slowing of motor nerve conduction velocity. Treatment of diabetic rats with aldose reductase inhibitors, aminoguanidine or myo-inositol supplementation have been shown to improve motor nerve conduction velocity and/or decreased endoneurial blood flow. However, the effect these treatments have on vascular reactivity of epineurial vessels of the sciatic nerve is unknown. In these studies we examined the effect of treating streptozotocininduced rats with sorbinil, aminoguanidine or myo-inositol on motor nerve conduction velocity, endoneurial blood flow and endothelium dependent vascular relaxation of arterioles that provide circulation to the region of the sciatic nerve. Treating diabetic rats with sorbinil, aminoguanidine or myo-inositol improved the reduction of endoneurial blood flow and motor nerve conduction velocity. However, only sorbinil treatment significantly improved the diabetes-induced impairment of acetylcholinemediated vasodilation of epineurial vessels of the sciatic nerve. All three treatments were efficacious in preventing the appropriate metabolic derangements associated with either activation of the polyol pathway or increased nonenzymatic glycation. In addition, sorbinil was shown to prevent the diabetes-induced decrease in lens glutathione level. However, other markers of oxidative stress were not vividly improved by these treatments. These studies suggest that sorbinil treatment may be more effective in preventing neural dysfunction in diabetes than either aminoguanidine or myoinositol. PMID:11900277

  6. Increased myo-inositol in parietal white and gray matter as a biomarker of poor prognosis in neuropsychiatric lupus: a case report.

    PubMed

    Guillen-Del Castillo, A; Alonso, J; Martínez-Valle, F; Alonso-Vila, S; Garrido-Castro, A C; Vilardell-Tarrés, M; Rovira, Á; Ordi-Ros, J

    2014-09-01

    Neuropsychiatric manifestations can be a serious complication of systemic lupus erythematosus, affecting nearly 56% of these patients. Frequently, acceptable clinical outcome is observed in neurolupus with immunosuppressive therapy. Different metabolites identified with MR spectroscopy may be associated with modifications in the natural history of this disease, specifically in the central nervous system. We report a case of neurolupus with progressive neurologic impairment despite aggressive immunosuppressive treatment. We describe clinical features, laboratory and MRI results, as well as characteristic findings on MR spectroscopy. Serial MRI identified atrophy of the left temporal lobe. MR spectroscopy showed an increase of myo-inositol/creatine ratio intensity, accompanied by a decrease of N-acetylaspartate/creatine ratio in both parietal white and gray matter. During follow-up, the patient developed progressive cognitive deficiency despite the intensification of therapy. Neurolupus manifestations are common and immunosuppressive treatment often avoids severe complications. Characteristic findings on MR spectroscopy may be useful for clinicians to determine poor prognosis and resistance to therapy.

  7. The Effects of Myo-Inositol and B and D Vitamin Supplementation in the db/+ Mouse Model of Gestational Diabetes Mellitus

    PubMed Central

    Plows, Jasmine F.; Budin, Florence; Andersson, Rebecka A. M.; Mills, Valerie J.; Mace, Katherine; Davidge, Sandra T.; Vickers, Mark H.; Baker, Philip N.; Silva-Zolezzi, Irma; Stanley, Joanna L.

    2017-01-01

    Gestational diabetes mellitus (GDM) is a growing concern, affecting an increasing number of pregnant women worldwide. By predisposing both the affected mothers and children to future disease, GDM contributes to an intergenerational cycle of obesity and diabetes. In order to stop this cycle, safe and effective treatments for GDM are required. This study sought to determine the treatment effects of dietary supplementation with myo-inositol (MI) and vitamins B2, B6, B12, and D in a mouse model of GDM (pregnant db/+ dams). In addition, the individual effects of vitamin B2 were examined. Suboptimal B2 increased body weight and fat deposition, decreased GLUT4 adipose tissue expression, and increased expression of inflammatory markers. MI supplementation reduced weight and fat deposition, and reduced expression of inflammatory markers in adipose tissue of mice on suboptimal B2. MI also significantly reduced the hyperleptinemia observed in db/+ mice, when combined with supplemented B2. MI was generally associated with adipose tissue markers of improved insulin sensitivity and glucose uptake, while the combination of vitamins B2, B6, B12, and D was associated with a reduction in adipose inflammatory marker expression. These results suggest that supplementation with MI and vitamin B2 could be beneficial for the treatment/prevention of GDM. PMID:28212289

  8. High binding affinity of repressor IolR avoids costs of untimely induction of myo-inositol utilization by Salmonella Typhimurium

    PubMed Central

    Hellinckx, Jessica; Heermann, Ralf; Felsl, Angela; Fuchs, Thilo M.

    2017-01-01

    Growth of Salmonella enterica serovar Typhimurium strain 14028 with myo-inositol (MI) is characterized by a bistable phenotype that manifests with an extraordinarily long (34 h) and variable lag phase. When cells were pre-grown in minimal medium with MI, however, the lag phase shortened drastically to eight hours, and to six hours in the absence of the regulator IolR. To unravel the molecular mechanism behind this phenomenon, we investigated this repressor in more detail. Flow cytometry analysis of the iolR promoter at a single cell level demonstrated bistability of its transcriptional activation. Electrophoretic mobility shift assays were used to narrow the potential binding region of IolR and identified at least two binding sites in most iol gene promoters. Surface plasmon resonance spectroscopy quantified IolR binding and indicated its putative oligomerization and high binding affinity towards specific iol gene promoters. In competitive assays, the iolR deletion mutant, in which iol gene repression is abolished, showed a severe growth disadvantage of ~15% relative to the parental strain in rich medium. We hypothesize that the strong repression of iol gene transcription is required to maintain a balance between metabolic flexibility and fitness costs, which follow the inopportune induction of an unusual metabolic pathway. PMID:28290506

  9. Reconstructed Ancestral Myo-Inositol-3-Phosphate Synthases Indicate That Ancestors of the Thermococcales and Thermotoga Species Were More Thermophilic than Their Descendants

    PubMed Central

    Butzin, Nicholas C.; Lapierre, Pascal; Green, Anna G.; Swithers, Kristen S.; Gogarten, J. Peter; Noll, Kenneth M.

    2013-01-01

    The bacterial genomes of Thermotoga species show evidence of significant interdomain horizontal gene transfer from the Archaea. Members of this genus acquired many genes from the Thermococcales, which grow at higher temperatures than Thermotoga species. In order to study the functional history of an interdomain horizontally acquired gene we used ancestral sequence reconstruction to examine the thermal characteristics of reconstructed ancestral proteins of the Thermotoga lineage and its archaeal donors. Several ancestral sequence reconstruction methods were used to determine the possible sequences of the ancestral Thermotoga and Archaea myo-inositol-3-phosphate synthase (MIPS). These sequences were predicted to be more thermostable than the extant proteins using an established sequence composition method. We verified these computational predictions by measuring the activities and thermostabilities of purified proteins from the Thermotoga and the Thermococcales species, and eight ancestral reconstructed proteins. We found that the ancestral proteins from both the archaeal donor and the Thermotoga most recent common ancestor recipient were more thermostable than their descendants. We show that there is a correlation between the thermostability of MIPS protein and the optimal growth temperature (OGT) of its host, which suggests that the OGT of the ancestors of these species of Archaea and the Thermotoga grew at higher OGTs than their descendants. PMID:24391933

  10. Reconstructed ancestral Myo-inositol-3-phosphate synthases indicate that ancestors of the Thermococcales and Thermotoga species were more thermophilic than their descendants.

    PubMed

    Butzin, Nicholas C; Lapierre, Pascal; Green, Anna G; Swithers, Kristen S; Gogarten, J Peter; Noll, Kenneth M

    2013-01-01

    The bacterial genomes of Thermotoga species show evidence of significant interdomain horizontal gene transfer from the Archaea. Members of this genus acquired many genes from the Thermococcales, which grow at higher temperatures than Thermotoga species. In order to study the functional history of an interdomain horizontally acquired gene we used ancestral sequence reconstruction to examine the thermal characteristics of reconstructed ancestral proteins of the Thermotoga lineage and its archaeal donors. Several ancestral sequence reconstruction methods were used to determine the possible sequences of the ancestral Thermotoga and Archaea myo-inositol-3-phosphate synthase (MIPS). These sequences were predicted to be more thermostable than the extant proteins using an established sequence composition method. We verified these computational predictions by measuring the activities and thermostabilities of purified proteins from the Thermotoga and the Thermococcales species, and eight ancestral reconstructed proteins. We found that the ancestral proteins from both the archaeal donor and the Thermotoga most recent common ancestor recipient were more thermostable than their descendants. We show that there is a correlation between the thermostability of MIPS protein and the optimal growth temperature (OGT) of its host, which suggests that the OGT of the ancestors of these species of Archaea and the Thermotoga grew at higher OGTs than their descendants.

  11. Myo-inositol as a main metabolite in overwintering flies: seasonal metabolomic profiles and cold stress tolerance in a northern drosophilid fly.

    PubMed

    Vesala, Laura; Salminen, Tiina S; Koštál, Vladimir; Zahradníčková, Helena; Hoikkala, Anneli

    2012-08-15

    Coping with seasonal changes in temperature is an important factor underlying the ability of insects to survive over the harsh winter conditions in the northern temperate zone, and only a few drosophilids have been able to colonize sub-polar habitats. Information on their winter physiology is needed as it may shed light on the adaptive mechanisms of overwintering when compared with abundant data on the thermal physiology of more southern species, such as Drosophila melanogaster. Here we report the first seasonal metabolite analysis in a Drosophila species. We traced changes in the cold tolerance and metabolomic profiles in adult Drosophila montana flies that were exposed to thermoperiods and photoperiods similar to changes in environmental conditions of their natural habitat in northern Finland. The cold tolerance of diapausing flies increased noticeably towards the onset of winter; their chill coma recovery times showed a seasonal minimum between late autumn and early spring, whereas their survival after cold exposure remained high until late spring. The flies had already moderately accumulated glucose, trehalose and proline in autumn, but the single largest change occurred in myo-inositol concentrations. This increased up to 400-fold during the winter and peaked at 147 nmol mg(-1) fresh mass, which is among the largest reported accumulations of this compound in insects.

  12. High binding affinity of repressor IolR avoids costs of untimely induction of myo-inositol utilization by Salmonella Typhimurium.

    PubMed

    Hellinckx, Jessica; Heermann, Ralf; Felsl, Angela; Fuchs, Thilo M

    2017-03-14

    Growth of Salmonella enterica serovar Typhimurium strain 14028 with myo-inositol (MI) is characterized by a bistable phenotype that manifests with an extraordinarily long (34 h) and variable lag phase. When cells were pre-grown in minimal medium with MI, however, the lag phase shortened drastically to eight hours, and to six hours in the absence of the regulator IolR. To unravel the molecular mechanism behind this phenomenon, we investigated this repressor in more detail. Flow cytometry analysis of the iolR promoter at a single cell level demonstrated bistability of its transcriptional activation. Electrophoretic mobility shift assays were used to narrow the potential binding region of IolR and identified at least two binding sites in most iol gene promoters. Surface plasmon resonance spectroscopy quantified IolR binding and indicated its putative oligomerization and high binding affinity towards specific iol gene promoters. In competitive assays, the iolR deletion mutant, in which iol gene repression is abolished, showed a severe growth disadvantage of ~15% relative to the parental strain in rich medium. We hypothesize that the strong repression of iol gene transcription is required to maintain a balance between metabolic flexibility and fitness costs, which follow the inopportune induction of an unusual metabolic pathway.

  13. The effect of microbial phytase and myo-inositol on performance and blood biochemistry of broiler chickens fed wheat/corn-based diets.

    PubMed

    Cowieson, A J; Ptak, A; Mackowiak, P; Sassek, M; Pruszynska-Oszmalek, E; Zyla, K; Swiatkiewicz, S; Kaczmarek, S; Józefiak, D

    2013-08-01

    A total of 1,200 Ross broiler chickens were used in 2 separate feeding studies to explore the effect of myo-inositol (MYO) and phytase on performance and blood biochemistry of broilers fed diets formulated to be either adequate or insufficient in Ca and digestible P (dP). Supplementation of diets that were formulated to be insufficient in Ca and dP with MYO resulted in improved BW gain and feed conversion ratio in both experiments. However, these effects were most pronounced in the finisher phase, and moderate negative effects were observed during the starter period. Supplementation of the diet with microbial phytase improved BW gain and feed conversion ratio to a similar extent as was observed with MYO, and there was a degree of subadditivity between the 2 additives. Blood glucose concentrations were increased by both MYO and phytase, though possibly by different mechanisms, because insulin concentrations were not directly relatable to circulating glucose levels, especially when both MYO and phytase were applied simultaneously. The increase in blood glucose concentrations with MYO and phytase was most pronounced in the diet with a lower Ca and dP concentration. It can be concluded that dietary supplementation with MYO or phytase was effective in improving performance of commercial broiler chickens. However, further work is required to explore complex ontogenetic effects of MYO and possible involvement of both MYO and phytase in Na-dependent transport mechanisms.

  14. Profile and bioavailability analysis of myo-inositol phosphates in rye bread supplemented with phytases: a study using an in vitro method and Caco-2 monolayers.

    PubMed

    Duliński, R; Cielecka, E K; Pierzchalska, M; Byczyński, Ł; Żyła, K

    2016-06-01

    Commercial preparations of 6-phytase A alone and in combination with phytase B were used in rye breadmaking. Determination of bioavailability of myo-inositol phosphates from bread was performed by an in vitro digestion method followed by the measurement of an uptake by Caco-2 cells in culture. In bread supplemented with a combination of 6-phytase A and phytase B, a significant reduction in phytate content was observed from 3.62 μmol/g in the control to 0.7 μmol/g. Bioavailability of phytate estimated by an in vitro method simulating digestion in the human alimentary tract was 9% in the bread supplemented with phytase B, 7% (6-phytase A) and 50% in the control bread. In cell culture, the bioaccessibilities of inositol triphosphates from bread baked with the addition of 6-phytase A was higher by 36% as compared to the samples baked with phytase B and by 32% in breads baked with combination of both phytases.

  15. Crystal structure of a substrate complex of myo-inositol oxygenase, a di-iron oxygenase with a key role in inositol metabolism.

    PubMed

    Brown, Peter M; Caradoc-Davies, Tom T; Dickson, James M J; Cooper, Garth J S; Loomes, Kerry M; Baker, Edward N

    2006-10-10

    Altered metabolism of the inositol sugars myo-inositol (MI) and d-chiro-inositol is implicated in diabetic complications. In animals, catabolism of MI and D-chiro-inositol depends on the enzyme MI oxygenase (MIOX), which catalyzes the first committed step of the glucuronate-xylulose pathway, and is found almost exclusively in the kidneys. The crystal structure of MIOX, in complex with MI, has been determined by multiwavelength anomalous diffraction methods and refined at 2.0-A resolution (R=0.206, Rfree=0.253). The structure reveals a monomeric, single-domain protein with a mostly helical fold that is distantly related to the diverse HD domain superfamily. Five helices form the structural core and provide six ligands (four His and two Asp) for the di-iron center, in which the two iron atoms are bridged by a putative hydroxide ion and one of the Asp ligands, Asp-124. A key loop forms a lid over the MI substrate, which is coordinated in bidentate mode to one iron atom. It is proposed that this mode of iron coordination, and interaction with a key Lys residue, activate MI for bond cleavage. The structure also reveals the basis of substrate specificity and suggests routes for the development of specific MIOX inhibitors.

  16. Biochemical properties and substrate specificities of alkaline and histidine acid phytases.

    PubMed

    Oh, B-C; Choi, W-C; Park, S; Kim, Y-o; Oh, T-K

    2004-01-01

    Phytases are a special class of phosphatase that catalyze the sequential hydrolysis of phytate to less-phosphorylated myo-inositol derivatives and inorganic phosphate. Phytases are added to animal feedstuff to reduce phosphate pollution in the environment, since monogastric animals such as pigs, poultry, and fish are unable to metabolize phytate. Based on biochemical properties and amino acid sequence alignment, phytases can be categorized into two major classes, the histidine acid phytases and the alkaline phytases. The histidine acid phosphatase class shows broad substrate specificity and hydrolyzes metal-free phytate at the acidic pH range and produces myo-inositol monophosphate as the final product. In contrast, the alkaline phytase class exhibits strict substrate specificity for the calcium-phytate complex and produces myo-inositol trisphosphate as the final product. This review describes recent findings that present novel viewpoints concerning the molecular basis of phytase classification.

  17. Seed Biofortification and Phytic Acid Reduction: A Conflict of Interest for the Plant?

    PubMed

    Sparvoli, Francesca; Cominelli, Eleonora

    2015-11-20

    Most of the phosphorus in seeds is accumulated in the form of phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate, InsP₆). This molecule is a strong chelator of cations important for nutrition, such as iron, zinc, magnesium, and calcium. For this reason, InsP₆ is considered an antinutritional factor. In recent years, efforts to biofortify seeds through the generation of low phytic acid (lpa) mutants have been noteworthy. Moreover, genes involved in the biosynthesis and accumulation of this molecule have been isolated and characterized in different species. Beyond its role in phosphorus storage, phytic acid is a very important signaling molecule involved in different regulatory processes during plant development and responses to different stimuli. Consequently, many lpa mutants show different negative pleitotropic effects. The strength of these pleiotropic effects depends on the specific mutated gene, possible functional redundancy, the nature of the mutation, and the spatio-temporal expression of the gene. Breeding programs or transgenic approaches aimed at development of new lpa mutants must take into consideration these different aspects in order to maximize the utility of these mutants.

  18. Seed Biofortification and Phytic Acid Reduction: A Conflict of Interest for the Plant?

    PubMed Central

    Sparvoli, Francesca; Cominelli, Eleonora

    2015-01-01

    Most of the phosphorus in seeds is accumulated in the form of phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate, InsP6). This molecule is a strong chelator of cations important for nutrition, such as iron, zinc, magnesium, and calcium. For this reason, InsP6 is considered an antinutritional factor. In recent years, efforts to biofortify seeds through the generation of low phytic acid (lpa) mutants have been noteworthy. Moreover, genes involved in the biosynthesis and accumulation of this molecule have been isolated and characterized in different species. Beyond its role in phosphorus storage, phytic acid is a very important signaling molecule involved in different regulatory processes during plant development and responses to different stimuli. Consequently, many lpa mutants show different negative pleitotropic effects. The strength of these pleiotropic effects depends on the specific mutated gene, possible functional redundancy, the nature of the mutation, and the spatio-temporal expression of the gene. Breeding programs or transgenic approaches aimed at development of new lpa mutants must take into consideration these different aspects in order to maximize the utility of these mutants. PMID:27135349

  19. Results from the International Consensus Conference on Myo-inositol and d-chiro-inositol in Obstetrics and Gynecology: the link between metabolic syndrome and PCOS.

    PubMed

    Facchinetti, Fabio; Bizzarri, Mariano; Benvenga, Salvatore; D'Anna, Rosario; Lanzone, Antonio; Soulage, Christophe; Di Renzo, Gian Carlo; Hod, Moshe; Cavalli, Pietro; Chiu, Tony T; Kamenov, Zdravko A; Bevilacqua, Arturo; Carlomagno, Gianfranco; Gerli, Sandro; Oliva, Mario Montanino; Devroey, Paul

    2015-12-01

    In recent years, interest has been focused to the study of the two major inositol stereoisomers: myo-inositol (MI) and d-chiro-inositol (DCI), because of their involvement, as second messengers of insulin, in several insulin-dependent processes, such as metabolic syndrome and polycystic ovary syndrome. Although these molecules have different functions, very often their roles have been confused, while the meaning of several observations still needs to be interpreted under a more rigorous physiological framework. With the aim of clarifying this issue, the 2013 International Consensus Conference on MI and DCI in Obstetrics and Gynecology identified opinion leaders in all fields related to this area of research. They examined seminal experimental papers and randomized clinical trials reporting the role and the use of inositol(s) in clinical practice. The main topics were the relation between inositol(s) and metabolic syndrome, polycystic ovary syndrome (with a focus on both metabolic and reproductive aspects), congenital anomalies, gestational diabetes. Clinical trials demonstrated that inositol(s) supplementation could fruitfully affect different pathophysiological aspects of disorders pertaining Obstetrics and Gynecology. The treatment of PCOS women as well as the prevention of GDM seem those clinical conditions which take more advantages from MI supplementation, when used at a dose of 2g twice/day. The clinical experience with MI is largely superior to the one with DCI. However, the existence of tissue-specific ratios, namely in the ovary, has prompted researchers to recently develop a treatment based on both molecules in the proportion of 40 (MI) to 1 (DCI).

  20. Screening and confirmation of myo-inositol trispyrophosphate (ITPP) in human urine by hydrophilic interaction liquid chromatography high resolution / high accuracy mass spectrometry for doping control purposes.

    PubMed

    Görgens, Christian; Guddat, Sven; Schänzer, Wilhelm; Thevis, Mario

    2014-01-01

    Myo-inositol trispyrophosphate (ITPP) is a novel allosteric effector of haemoglobin with high permeation selectivity across the red blood cell plasma membrane. Due to its potential to reduce the oxygen affinity of haemoglobin, ITPP application results in an enhanced oxygen release in hypoxic tissues. Therefore, ITPP is being examined for the treatment of numerous illnesses that involve hypoxia, such as cardiovascular diseases, cancer or Alzheimer's disease. Similar to the prohibited substance Efaproxiral®, ITPP increases maximal exercise capacity in mice, providing high potential to be misused in sports. To keep up with cheating athletes, a fast and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for screening and confirmation of ITPP in human urine for doping control purposes was developed. According to the molecule's distinct hydrophilic properties, extraction from complex biological matrices is challenging and conventional reversed phase liquid chromatography (RPLC) separations are not suitable for its detection. Therefore an approach based on hydrophilic interaction liquid chromatography (HILIC) Orbitrap mass spectrometry was established. The methodology was fully validated for qualitative purposes. Screening and confirmation assay are characterized by satisfactory specificity and robustness, adequate intra-day (screening: 4.9-8.1%; confirmation: 2.0-6.7%) and inter-day precision (screening: 4.6-9.1%; confirmation: 1.8-6.6%), excellent linear correlations (>0.99) with sufficient LLOD in the sub ng/mL range (screening: 15 ng/mL; confirmation: 1 ng/mL). In addition it could be shown that ITPP is stable in human urine under the mandatory storage period and conditions for doping control laboratories. To our knowledge, this is the first validated 'dilute-and-inject' LC-MS/MS method for the reliable detection of ITPP in human urine.

  1. The transport mechanism of the human sodium/myo-inositol transporter 2 (SMIT2/SGLT6), a member of the LeuT structural family.

    PubMed

    Sasseville, Louis J; Longpré, Jean-Philippe; Wallendorff, Bernadette; Lapointe, Jean-Yves

    2014-09-01

    The sodium/myo-inositol transporter 2 (SMIT2) is a member of the SLC5A gene family, which is believed to share the five-transmembrane segment inverted repeat of the LeuT structural family. The two-electrode voltage-clamp (TEVC) technique was used to measure the steady-state and the pre-steady-state currents mediated by human SMIT2 after expression in Xenopus laevis oocytes. Phlorizin is first shown to be a poor inhibitor of pre-steady-state currents for depolarizing voltage pulse. From an up to threefold difference between the apparent ON and OFF transferred charges during a voltage pulse, we also show that a fraction of the transient current recorded for very negative potentials is not a true pre-steady-state current coming from the cotransporter conformational changes. We suggest that this transient current comes from a time-dependent leak current that can reach large amplitudes when external Na(+) concentration is reduced. A kinetic model was generated through a simulated annealing algorithm. This algorithm was used to identify the optimal connectivity among 19 different kinetic models and obtain the numerical values of the associated parameters. The proposed 5-state model includes cooperative binding of Na(+) ions, strong apparent asymmetry of the energy barriers, a rate-limiting step that is likely associated with the translocation of the empty transporter, and a turnover rate of 21 s(-1). The proposed model is a proof of concept for a novel approach to kinetic modeling of electrogenic transporters and allows insight into the transport mechanism of members of the LeuT structural family at the millisecond timescale.

  2. Expression analysis of a heat-inducible, Myo-inositol-1-phosphate synthase (MIPS) gene from wheat and the alternatively spliced variants of rice and Arabidopsis.

    PubMed

    Khurana, Neetika; Chauhan, Harsh; Khurana, Paramjit

    2012-01-01

    Molecular dissection and a deeper analysis of the heat stress response mechanism in wheat have been poorly understood so far. This study delves into the molecular basis of action of TaMIPS, a heat stress-inducible enzyme that was identified through PCR-select subtraction technology, which is named here as TaMIPS2. MIPS (L-Myo-inositol-phosphate synthase) is important for the normal growth and development in plants. Expression profiling showed that TaMIPS2 is expressed during different developing seed stages upon heat stress. Also, the transcript levels increase in unfertilized ovaries and significant amounts are present during the recovery period providing evidence that MIPS is crucial for its role in heat stress recovery and flower development. Alternatively spliced forms from rice and Arabidopsis were also identified and their expression analysis revealed that apart from heat stress, some of the spliced variants were also inducible by drought, NaCl, Cold, ABA, BR, SA and mannitol. In silico promoter analysis revealed various cis-elements that could contribute for the differential regulation of MIPS in different plant systems. Phylogenetic analysis indicated that MIPS are highly conserved among monocots and dicots and TaMIPS2 grouped specifically with monocots. Comparative analyses was undertaken by different experimental approaches, i.e., semi-quantitative RT-PCR, quantitative RT-PCR, Genevestigator as a reference expression tool and motif analysis to predict the possible function of TaMIPS2 in regulating the different aspects of plant development under abiotic stress in wheat.

  3. A decrease in phytic acid content substantially affects the distribution of mineral elements within rice seeds.

    PubMed

    Sakai, Hiroaki; Iwai, Toru; Matsubara, Chie; Usui, Yuto; Okamura, Masaki; Yatou, Osamu; Terada, Yasuko; Aoki, Naohiro; Nishida, Sho; Yoshida, Kaoru T

    2015-09-01

    Phytic acid (myo-inositol hexakisphosphate; InsP6) is the storage compound of phosphorus and many mineral elements in seeds. To determine the role of InsP6 in the accumulation and distribution of mineral elements in seeds, we performed fine mappings of mineral elements through synchrotron-based X-ray microfluorescence analysis using developing seeds from two independent low phytic acid (lpa) mutants of rice (Oryza sativa L.). The reduced InsP6 in lpa seeds did not affect the translocation of mineral elements from vegetative organs into seeds, because the total amounts of phosphorus and the other mineral elements in lpa seeds were identical to those in the wild type (WT). However, the reduced InsP6 caused large changes in mineral localization within lpa seeds. Phosphorus and potassium in the aleurone layer of lpa greatly decreased and diffused into the endosperm. Zinc and copper, which were broadly distributed from the aleurone layer to the inner endosperm in the WT, were localized in the narrower space around the aleurone layer in lpa mutants. We also confirmed that similar distribution changes occurred in transgenic rice with the lpa phenotype. Using these results, we discussed the role of InsP6 in the dynamic accumulation and distribution patterns of mineral elements during seed development.

  4. The effect of dietary supplementation with limonene or myo-inositol on the induction of neoplasia and matrix metalloproteinase and plasminogen activator activities in accessory sex organs of male Lobund-Wistar rats.

    PubMed

    Wilson, Michael J; Lindgren, Bruce R; Sinha, Akhouri A

    2008-10-01

    Prostate cancer, the most prevalent non-cutaneous cancer in men, is associated with increased age. This suggests that dietary chemopreventive measures could be effective in delaying the onset or decreasing the severity of the disease. We utilized the Lobund-Wistar rat nitrosomethylurea induced, testosterone promoted (NMU-T) model of male sex accessory gland cancer to test the potential chemopreventive effects of myo-inositol and limonene on tumor incidence and associated protease activities. Tumors were found to arise in the seminal vesicles and dorsal and anterior prostate lobes. There were also some tumors that appeared to arise in both the seminal vesicles and anterior prostate, and in some cases the tissue of origin was not clear. The distribution of tumors as to site of origin in limonene or myo-inositol treated animals did not vary from that of the starch fed control animals, and the number of animals presenting with metastases did not vary significantly between treatment groups. There was a statistically significant delay in onset of tumors in myo-inositol, but not limonene fed rats, at 10 months post-induction of carcinogenesis; however, at 12 and 15 months this was not significant. The ventral prostate and seminal vesicles expressed pro-MMP-2 and plasminogen activator (PA) activities. Based on sensitivity to amiloride, the PA activities were predominately urokinase (uPA) in the ventral prostate and a mixture of tissue-type activator (tPA) and uPA in the seminal vesicles of non-treated rats. Sex accessory gland tumors, and metastases, expressed increased levels PA and pro- and active forms of MMP-2 and -9. The PA activities of the tumors were a mixture of uPA and tPA. There was no difference in the levels of these protease activities based on the tissue of tumor origin, nor in tumor vs metastasis. These studies indicate that MMP and PA activities play a role in sex accessory gland tumor biology and that dietary supplementation with myo-inositol can delay

  5. Forward genetics studies of seed phytic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both the chemical composition and total amount of seed phosphorus (P) are important to the end-use quality of cereal and legume seed crops. The chemistry of seed total P largely revolves around the synthesis and storage of phytic acid (myo-inositol hexaphosphate). Forward genetics research, beginnin...

  6. Low Phytic Acid Barley Responses to Phosphorus Rates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low phytic acid (LPA) barley (Hordeum vulgare L.) cultivars partition phosphorus in seed tissue differently than conventional barley cultivars through a reduction in seed phytic acid (myo-inositol-1,2,3,4,5,6-hexkisphosphate) coupled with an increase in inorganic phosphorus. The response of the LPA...

  7. Bergmann glial S100B activates myo-inositol monophosphatase 1 and Co-localizes to purkinje cell vacuoles in SCA1 transgenic mice.

    PubMed

    Vig, Parminder J S; Shao, Qingmei; Subramony, S H; Lopez, Mariper E; Safaya, Eshan

    2009-09-01

    Spinocerebellar ataxia-1 (SCA1) is a late onset neurodegenerative disease caused by the expansion of a polyglutamine repeat within ataxin-1 protein. The toxic effects triggered by mutant ataxin-1 result in degeneration of the neurons in cerebellum, brain stem and spinocerebellar tracts. The targeted overexpression of mutant ataxin-1 in cerebellar Purkinje cells (PCs) of the SCA1 transgenic mice results in the formation of cytoplasmic vacuoles in PCs. These vacuoles appear early on before the onset of behavioral abnormalities. Interestingly, we found that vacoules contain S100B and vimentin proteins, which normally localize to neighboring Bergmann glia (BG). Further, immunohistochemical and specialized silver stain analysis revealed that vacuolar formation is associated with alterations in the morphology of dendritic spines of PCs. To gain insights into the mechanisms of vacuolar formation, we investigated if vacuoles in SCA1 PCs have an autophagic origin or are a consequence of some other event. We examined the expression levels (by Western blotting) of microtubule-associated protein light chain 3 (LC3)-I and LC3-II, and the degradation levels of p62 (a LC3 partner) in the cerebellar fractions prepared from pre-symptomatic SCA1 and age-matched wild-type mice. No p62 degradation was observed; however, LC3-II/(LC3-I + LC3-II) ratios were significantly altered in SCA1 mice indicating changes in the autophagic flux. In addition, LC3 localized to PC vacuoles. Further, we observed a co-localization of myo-inositol monophosphatase 1 (IMPA1) with S100B in PC vacuoles. IMPA1 is present in PC spines and has been implicated in autophagy. In vitro studies using purified IMPA1 and S100B demonstrated that S100B interacted with and activated IMPA1. Both apo and Ca(2+)-bound S100B were found to activate IMPA1, depending on substrate concentration. IMPA1 is regulated by another calcium-binding protein calbindin-D28k (CaB), since we reported earlier that the CaB levels are reduced

  8. Arabidopsis plants constitutively overexpressing a myo-inositol 1-phosphate synthase gene (SaINO1) from the halophyte smooth cordgrass exhibits enhanced level of tolerance to salt stress.

    PubMed

    Joshi, Rohit; Ramanarao, Mangu Venkata; Baisakh, Niranjan

    2013-04-01

    Salinity is one of the most important environmental constraints limiting agricultural productivity. Considering the importance of the accumulation of osmolytes, myo-inositol in particular, in halophytic plant's adaptive response to salinity, an effort was made to overexpress the SaINO1 gene from the grass halophyte Spartina alterniflora encoding myo-inositol 1-phosphate synthase (MIPS) in Arabidopsis thaliana. We demonstrated that SaINO1 is a stress-responsive gene and its constitutive over expression in Arabidopsis provides significantly improved tolerance to salt stress during germination and seedling growth and development. The transgenics retained more chlorophyll and carotenoid by protecting the photosystem II. The low level of stress-induced cellular damage in the transgenics was clearly evident by lower accumulation of proline in comparison to WT. Our results indicated that possible overaccumulation of MIPS enzyme in the cytosol protected the transgenic Arabidopsis plants overexpressing SaINO1 from the toxic effect of Na(+) under salt stress by reducing cellular damage and chlorophyll loss.

  9. /sup 2/H-NMR studies of hypocotyl cell walls of germinating beams supplied with perdeuterated myo-inositol

    SciTech Connect

    Sasaki, K.; Wallace, J.C.; MacKay, A.L.; Balza, F.; Taylor, I.E.P.

    1987-04-01

    When myo-(2-/sup 3/H) inositol (MI) was supplied to bean seeds by imbibition, only uronic acid, arabinose and xylose residues of cell wall polysaccharides were labeled. To study the structural mobility of the uronic acid- and/or pentose-rich polysaccharides in cell wall using /sup 2/H-NMR, the authors supplied perdeuterated MI with (2-/sup 3/H) MI to germinating bean seeds. Perdeuterated MI was prepared by the /sup 1/H-/sup 2/H exchange reaction of MI in deuterium oxide with Raney nickel. During the exchange reaction, extensive epimerization occurred and at least 6 inositol epimers in addition to MI were identified in the reaction mixture of GC/MS. The perdeuterated MI was completely resolved from other inositol epimers and purified by anion-exchange chromatography using Dowex 1 (borate form) and by crystallization. The /sup 2/H-NMR analysis resolved the /sup 2/H-labeled hypocotyl cell walls into two components (rigid and mobile components). They also report the distribution of /sup 2/H and /sup 3/H from perdeuterated and (2-/sup 3/H) MI in the cell wall sugar residues.

  10. Seed phosphorus and inositol phosphate phenotype of barley low phytic acid genotypes.

    PubMed

    Dorsch, John A; Cook, Allen; Young, Kevin A; Anderson, Joseph M; Bauman, Andrew T; Volkmann, Carla J; Murthy, Pushpalatha P N; Raboy, Victor

    2003-03-01

    myo-Inositol-1,2,3,4,5,6-hexakisphosphate (Ins P(6) or "phytic acid") typically represents approximately 75% of the total phosphorus and >80% of soluble myo-inositol (Ins) phosphates in seeds. The seed phosphorus and Ins phosphate phenotypes of four non-lethal barley (Hordeum vulgare L.) low phytic acid mutations are described. In seeds homozygous for M 635 and M 955 reductions in Ins P(6), approximately 75 and >90% respectively, are accompanied by reductions in other Ins phosphates and molar-equivalent increases in Pi. This phenotype suggests a block in supply of substrate Ins. In seeds homozygous for barley low phytic acid 1-1 (lpa1-1), a 45% decrease in Ins P(6) is mostly matched by an increase in Pi but also accompanied by small increases in Ins(1,2,3,4,6)P(5). In seeds homozygous for barley lpa2-1, reductions in seed Ins P(6) are accompanied by increases in both Pi and in several Ins phosphates, a phenotype that suggests a lesion in Ins phosphate metabolism, rather than Ins supply. The increased Ins phosphates in barley lpa2-1 seed are: Ins(1,2,3,4,6)P(5); Ins(1,2,4,6)P(4) and/or its enantiomer Ins(2,3,4,6)P(4); Ins(1,2,3,4)P(4) and/or its enantiomer Ins(1,2,3,6)P(4); Ins(1,2,6)P(3) and/or its enantiomer Ins(2,3,4)P(3); Ins(1,5,6)P(3) and/or its enantiomer Ins(3,4,5)P(3) (the methods used here cannot distinguish between enantiomers). This primarily "5-OH" series of Ins phosphates differs from the "1-/3-OH" series observed at elevated levels in seed of the maize lpa2 genotype, but previous chromosomal mapping data indicated that the maize and barley lpa2 loci might be orthologs of a single ancestral gene. Therefore one hypothesis that might explain the differing lpa2 phenotypes is that their common ancestral gene encodes a multi-functional, Ins phosphate kinase with both "1-/-3-" and "5-kinase" activities. A putative pyrophosphate-containing Ins phosphate, possibly an Ins P(7), was also observed in the mature seed of all barley genotypes except lpa2-1. Barley M

  11. Production of Glucaric Acid from a Synthetic Pathway in Recombinant Escherichia coli▿ †

    PubMed Central

    Moon, Tae Seok; Yoon, Sang-Hwal; Lanza, Amanda M.; Roy-Mayhew, Joseph D.; Prather, Kristala L. Jones

    2009-01-01

    A synthetic pathway has been constructed for the production of glucuronic and glucaric acids from glucose in Escherichia coli. Coexpression of the genes encoding myo-inositol-1-phosphate synthase (Ino1) from Saccharomyces cerevisiae and myo-inositol oxygenase (MIOX) from mice led to production of glucuronic acid through the intermediate myo-inositol. Glucuronic acid concentrations up to 0.3 g/liter were measured in the culture broth. The activity of MIOX was rate limiting, resulting in the accumulation of both myo-inositol and glucuronic acid as final products, in approximately equal concentrations. Inclusion of a third enzyme, uronate dehydrogenase (Udh) from Pseudomonas syringae, facilitated the conversion of glucuronic acid to glucaric acid. The activity of this recombinant enzyme was more than 2 orders of magnitude higher than that of Ino1 and MIOX and increased overall flux through the pathway such that glucaric acid concentrations in excess of 1 g/liter were observed. This represents a novel microbial system for the biological production of glucaric acid, a “top value-added chemical” from biomass. PMID:19060162

  12. Quantification of myo-inositol, 1,5-anhydro-D-sorbitol, and D-chiro-inositol using high-performance liquid chromatography with electrochemical detection in very small volume clinical samples

    PubMed Central

    Schimpf, Karen J.; Meek, Claudia C.; Leff, Richard D.; Phelps, Dale L.; Schmitz, Daniel J.; Cordle, Christopher T.

    2015-01-01

    Inositol is a six-carbon sugar alcohol and is one of nine biologically significant isomers of hexahydroxycyclohexane. Myo-inositol is the primary biologically active form and is present in higher concentrations in the fetus and newborn than in adults. It is currently being examined for the prevention of retinopathy of prematurity in newborn preterm infants. A robust method for quantifying myo-inositol (MI), D-chiro-inositol (DCI) and 1,5-anhydro-D-sorbitol (ADS) in very small-volume (25 μL) urine, blood serum and/or plasma samples was developed. Using a multiple-column, multiple mobile phase liquid chromatographic system with electrochemical detection, the method was validated with respect to (a) selectivity, (b) accuracy/recovery, (c) precision/reproducibility, (d) sensitivity, (e) stability and (f) ruggedness. The standard curve was linear and ranged from 0.5 to 30 mg/L for each of the three analytes. Above-mentioned performance measures were within acceptable limits described in the Food and Drug Administration’s Guidance for Industry: Bioanalytical Method Validation. The method was validated using blood serum and plasma collected using four common anticoagulants, and also by quantifying the accuracy and sensitivity of MI measured in simulated urine samples recovered from preterm infant diaper systems. The method performs satisfactorily measuring the three most common inositol isomers on 25 μL clinical samples of serum, plasma milk, and/or urine. Similar performance is seen testing larger volume samples of infant formulas and infant formula ingredients. MI, ADS and DCI may be accurately tested in urine samples collected from five different preterm infant diapers if the urine volume is greater than 2–5 mL. PMID:26010453

  13. Approaches and Challenges to Engineering Seed Phytate and Total Phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    About 75% of seed total phosphorus (P) is found in a single compound, phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate or InsP6). Phytic acid is not efficiently utilized by monogastric animals (poultry, swine, fish), which creates phosphorus management and environmental impact problems in anim...

  14. Evaluation and Development of Low Phytate Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytic acid (myo-inositol 1,2,3,4,5,6 hexakisphosphate) is the most abundant form of phosphorus (P) in plant seeds, representing ~70%±10% of seed total P. Non-ruminant, mono-gastric animals (poultry, swine, fish), typically do not efficiently digest and utilize seed-derived phytic acid P. This creat...

  15. Identification and characterization of the soybean IPK1 ortholog of a low phytic acid mutant reveals an exon-excluding splice-site mutation.

    PubMed

    Yuan, Feng-Jie; Zhu, Dan-Hua; Tan, Yuan-Yuan; Dong, De-Kun; Fu, Xu-Jun; Zhu, Shen-Long; Li, Bai-Quan; Shu, Qing-Yao

    2012-11-01

    Phytic acid (myo-inositol 1, 2, 3, 4, 5, 6 hexakisphosphate) is an important constituent of soybean meal. Since phytic acid and its mineral salts (phytates) are almost indigestible for monogastrics, their abundance in grain food/feed causes nutritional and environmental problems; interest in breeding low phytic acid has therefore increased considerably. Based on gene mapping and the characteristics of inositol polyphosphates profile in the seeds of a soybean mutant line Gm-lpa-ZC-2, the soybean ortholog of inositol 1,3,4,5,6 pentakisphosphate (InsP(5)) 2-kinase (IPK1), which transforms InsP(5) into phytic acid, was first hypothesized as the candidate gene responsible for the low phytic acid alteration in Gm-lpa-ZC-2. One IPK1 ortholog (Glyma14g07880, GmIPK1) was then identified in the mapped region on chromosome 14. Sequencing revealed a G → A point mutation in the genomic DNA sequence and the exclusion of the entire fifth exon in the cDNA sequence of GmIPK1 in Gm-lpa-ZC-2 compared with its wild-type progenitor Zhechun No. 3. The excluded exon encodes 37 amino acids that spread across two conserved IPK1 motifs. Furthermore, complete co-segregation of low phytic acid phenotype with the G → A mutation was observed in the F(2) population of ZC-lpa x Zhexiandou No. 4 (a wild-type cultivar). Put together, the G → A point mutation affected the pre-mRNA splicing and resulted in the exclusion of the fifth exon of GmIPK1 which is expected to disrupt the GmIPK1 functionality, leading to low phytic acid level in Gm-lpa-ZC-2. Gm-lpa-ZC-2, would be a good germplasm source in low phytic acid soybean breeding.

  16. Preparative Procedures Markedly Influence the Appearance and Structural Integrity of Protein Storage Vacuoles in Soybean Seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In legumes, vacuoles serve as the final depository for storage proteins. The protein storage vacuoles (PSVs) of soybean contain electron-transparent globoid regions in which phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate) is sequestered. Here, I report the effect of preparative procedures o...

  17. Correlation of the solid-state reactivities of racemic 2,4(6)-di-O-benzoyl-myo-inositol 1,3,5-orthoformate and its 4,4'-bipyridine cocrystal with their crystal structures.

    PubMed

    Tamboli, Majid I; Bahadur, Vir; Gonnade, Rajesh G; Shashidhar, Mysore S

    2014-11-01

    Racemic 2,4(6)-di-O-benzoyl-myo-inositol 1,3,5-orthoformate, C21H18O8, (1), shows a very efficient intermolecular benzoyl-group migration reaction in its crystals. However, the presence of 4,4'-bipyridine molecules in its cocrystal, C21H18O8·C10H8N2, (1)·BP, inhibits the intermolecular benzoyl-group transfer reaction. In (1), molecules are assembled around the crystallographic twofold screw axis (b axis) to form a helical self-assembly through conventional O-H···O hydrogen-bonding interactions. This helical association places the reactive C6-O-benzoyl group (electrophile, El) and the C4-hydroxy group (nucleophile, Nu) in proximity, with a preorganized El···Nu geometry favourable for the acyl transfer reaction. In the cocrystal (1)·BP, the dibenzoate and bipyridine molecules are arranged alternately through O-H···N interactions. The presence of the bipyridine molecules perturbs the regular helical assembly of the dibenzoate molecules and thus restricts the solid-state reactivity. Hence, unlike the parent dibenzoate crystals, the cocrystals do not exhibit benzoyl-transfer reactions. This approach is useful for increasing the stability of small molecules in the crystalline state and could find application in the design of functional solids.

  18. Genome-Wide Screening of Salt Tolerant Genes by Activation-Tagging Using Dedifferentiated Calli of Arabidopsis and Its Application to Finding Gene for Myo-Inositol-1-P-Synthase

    PubMed Central

    Ahmad, Aftab; Niwa, Yasuo; Goto, Shingo; Kobayashi, Kyoko; Shimizu, Masanori; Ito, Sohei; Usui, Yumiko; Nakayama, Tsutomu; Kobayashi, Hirokazu

    2015-01-01

    Salinity represents a major abiotic stress factor that can adversely limit the production, quality and geographical distribution of crops. In this study we focused on dedifferentiated calli with fundamental cell functions, the salt tolerance of which had not been previously examined. The experimental approach was based on activation tagging without regeneration of plants for the identification of salt-tolerant mutants of Arabidopsis. Among 62,000 transformed calli that were screened, 18 potential mutants resistant to 150 mM NaCl were obtained. Thermal asymmetric interlaced (TAIL)-PCR was performed to determine the location of T-DNA integration in the genome. In one line, referred to as salt tolerant callus 1 (stc1), expression of a gene [At4g39800: myo-inositol-1-P-synthase 1 (MIPS1)] was considerably enhanced in calli. Plants regenerated from calli showed tolerance to salt in germination and subsequent growth. Retransformation of wild-type Arabidopsis with MIPS1 conferred salt tolerance, indicating that MIPS1 is the causal gene. The over-expression of MIPS1 increased the content of total inositol. The involvement of MIPS1 in salt tolerance through the fundamental cell growth has been proved in Arabidopsis. PMID:25978457

  19. Inositol phosphatase activity of the Escherichia coli agp-encoded acid glucose-1-phosphatase.

    PubMed

    Cottrill, Michael A; Golovan, Serguei P; Phillips, John P; Forsberg, Cecil W

    2002-09-01

    When screening an Escherichia coli gene library for myo-inositol hexakisphosphate (InsP6) phosphatases (phytases), we discovered that the agp-encoded acid glucose-1-phosphatase also possesses this activity. Purified Agp hydrolyzes glucose-1-phosphate, p-nitrophenyl phosphate, and InsP6 with pH optima, 6.5, 3.5, and 4.5, respectively, and was stable when incubated at pH values ranging from 3 to 10. Glucose-1-phosphate was hydrolyzed most efficiently at 55 degrees C. while InsP6 and p-nitrophenyl phosphate were hydrolyzed maximally at 60 degrees C. The Agp exhibited Km values of (0.39 mM, 13 mM, and 0.54 mM for the hydrolysis of glucose-1-phosphate, p-nitrophenyl phosphate, and InsP6, respectively. High-pressure liquid chromatography (HPLC) analysis of inositol phosphate hydrolysis products of Agp demonstrated that the enzyme catalyzes the hydrolysis of phosphate from each of InsP6, D-Ins(1,2,3,4,5)P5, Ins(1,3,4,5,6)P5, and Ins(1,2,3,4,6)P5, producing D/L-Ins(1,2,4,5,6)P5. D-Ins(1,2,4,5)P4, D/L-Ins(1,4,5,6)P4 and D/L-Ins(1,2,4,6)P4, respectively. These data support the contention that Agp is a 3-phosphatase.

  20. The low phytic acid1-241 (lpa1-241) maize mutation alters the accumulation of anthocyanin pigment in the kernel.

    PubMed

    Badone, Francesco Cerino; Cassani, Elena; Landoni, Michela; Doria, Enrico; Panzeri, Dario; Lago, Chiara; Mesiti, Francesca; Nielsen, Erik; Pilu, Roberto

    2010-04-01

    The lpa1 mutations in maize are caused by lesions in the ZmMRP4 (multidrug resistance-associated proteins 4) gene. In previous studies (Raboy et al. in Plant Physiol 124:355-368, 2000; Pilu et al. in Theor Appl Genet 107:980-987, 2003a; Shi et al. Nat Biotechnol 25:930-937, 2007), several mutations have been isolated in this locus causing a reduction of phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate, or InsP(6)) content and an equivalent increasing of free phosphate. In particular, the lpa1-241 mutation causes a reduction of up to 90% of phytic acid, associated with strong pleiotropic effects on the whole plant. In this work, we show, for the first time to our knowledge, an interaction between the accumulation of anthocyanin pigments in the kernel and the lpa mutations. In fact the lpa1-241 mutant accumulates a higher level of anthocyanins as compared to wild type either in the embryo (about 3.8-fold) or in the aleurone layer (about 0.3-fold) in a genotype able to accumulate anthocyanin. Furthermore, we demonstrate that these pigments are mislocalised in the cytoplasm, conferring a blue pigmentation of the scutellum, because of the neutral/basic pH of this cellular compartment. As a matter of fact, the propionate treatment, causing a specific acidification of the cytoplasm, restored the red pigmentation of the scutellum in the mutant and expression analysis showed a reduction of ZmMRP3 anthocyanins' transporter gene expression. On the whole, these data strongly suggest a possible interaction between the lpa mutation and anthocyanin accumulation and compartmentalisation in the kernel.

  1. 3-hydroxybenzene 1,2,4-trisphosphate, a novel second messenger mimic and unusual substrate for type-I myo-inositol 1,4,5-trisphosphate 5-phosphatase: Synthesis and physicochemistry.

    PubMed

    Mills, Stephen J; Dozol, Hélène; Vandeput, Fabrice; Backers, Katrien; Woodman, Timothy; Erneux, Christophe; Spiess, Bernard; Potter, Barry V L

    2006-11-01

    3-Hydroxybenzene 1,2,4-trisphosphate 4 is a new myo-inositol 1,4,5-trisphosphate analogue based on the core structure of benzene 1,2,4-trisphosphate 2 with an additional hydroxyl group at position-3, and is the first noninositol based compound to be a substrate for inositol 1,4,5-trisphosphate 5-phosphatase. In physicochemical studies on 2, when three equivalents of protons were added, the (31)P NMR spectrum displayed monophasic behaviour in which phosphate-1 and phosphate-2 behaved independently in most of the studied pH range. For compound 4, phosphate-2 and phosphate-4 interacted with the 3-OH group, which does not titrate at physiological pH, displaying complex biphasic behaviour which demonstrated co-operativity between these groups. Phosphate-1 and phosphate-2 strongly interacted with each other and phosphate-4 experienced repulsion because of the interaction of the 3-OH group. Benzene 1,2,4-trisphosphate 2 is resistant to inositol 1,4,5-trisphosphate type I 5-phosphatase catalysed dephosphorylation. However, surprisingly, 3-hydroxybenzene 1,2,4-trisphosphate 4 was dephosphorylated by this 5-phosphatase to give the symmetrical 2,3-dihydroxybenzene 1,4-bisphosphate 16. The extra hydroxyl group is shown to form a hydrogen bond with the vicinal phosphate groups at -15 degrees C, and (1)H NMR titration of the ring and hydroxyl protons in 4 shows the OH proton to be strongly stabilized as soon as the phosphate groups are deprotonated. The effect of the phenolic 3-OH group in compound 4 confirms a critical role for the 6-OH group of the natural messenger in the dephosphorylation mechanism that persists even in radically modified analogues.

  2. Tethered phytic acid as a probe for measuring phytase activity.

    PubMed

    Berry, Duane F; Berry, David A

    2005-06-15

    A novel approach for measuring phytase activity is presented. We have developed a new chromophoric substrate analog of phytic acid, 5-O-[6-(benzoylamino)hexyl]-d-myo-inositol-1,2,3,4,6-pentakisphosphate that permits direct measurement of the phosphate ester bond-cleavage reaction using HPLC. This compound, along with its dephosphorylated T-phosphatidylinositol intermediates, are quantified using reversed phase chromatography with UV detection.

  3. InsP6-Sensitive Variants of the Gle1 mRNA Export Factor Rescue Growth and Fertility Defects of the ipk1 Low-Phytic-Acid Mutation in Arabidopsis

    PubMed Central

    Lee, Ho-Seok; Lee, Du-Hwa; Cho, Hui Kyung; Kim, Song Hee; Auh, Joong Hyuck; Pai, Hyun-Sook

    2015-01-01

    Myo-inositol-1,2,3,4,5,6-hexakisphosphate (InsP6), also known as phytic acid, accumulates in large quantities in plant seeds, serving as a phosphorus reservoir, but is an animal antinutrient and an important source of water pollution. Here, we report that Gle1 (GLFG lethal 1) in conjunction with InsP6 functions as an activator of the ATPase/RNA helicase LOS4 (low expression of osmotically responsive genes 4), which is involved in mRNA export in plants, supporting the Gle1-InsP6-Dbp5 (LOS4 homolog) paradigm proposed in yeast. Interestingly, plant Gle1 proteins have modifications in several key residues of the InsP6 binding pocket, which reduce the basicity of the surface charge. Arabidopsis thaliana Gle1 variants containing mutations that increase the basic charge of the InsP6 binding surface show increased sensitivity to InsP6 concentrations for the stimulation of LOS4 ATPase activity in vitro. Expression of the Gle1 variants with enhanced InsP6 sensitivity rescues the mRNA export defect of the ipk1 (inositol 1,3,4,5,6-pentakisphosphate 2-kinase) InsP6-deficient mutant and, furthermore, significantly improves vegetative growth, seed yield, and seed performance of the mutant. These results suggest that Gle1 is an important factor responsible for mediating InsP6 functions in plant growth and reproduction and that Gle1 variants with increased InsP6 sensitivity may be useful for engineering high-yielding low-phytate crops. PMID:25670768

  4. InsP6-sensitive variants of the Gle1 mRNA export factor rescue growth and fertility defects of the ipk1 low-phytic-acid mutation in Arabidopsis.

    PubMed

    Lee, Ho-Seok; Lee, Du-Hwa; Cho, Hui Kyung; Kim, Song Hee; Auh, Joong Hyuck; Pai, Hyun-Sook

    2015-02-01

    Myo-inositol-1,2,3,4,5,6-hexakisphosphate (InsP(6)), also known as phytic acid, accumulates in large quantities in plant seeds, serving as a phosphorus reservoir, but is an animal antinutrient and an important source of water pollution. Here, we report that Gle1 (GLFG lethal 1) in conjunction with InsP(6) functions as an activator of the ATPase/RNA helicase LOS4 (low expression of osmotically responsive genes 4), which is involved in mRNA export in plants, supporting the Gle1-InsP(6)-Dbp5 (LOS4 homolog) paradigm proposed in yeast. Interestingly, plant Gle1 proteins have modifications in several key residues of the InsP(6) binding pocket, which reduce the basicity of the surface charge. Arabidopsis thaliana Gle1 variants containing mutations that increase the basic charge of the InsP(6) binding surface show increased sensitivity to InsP(6) concentrations for the stimulation of LOS4 ATPase activity in vitro. Expression of the Gle1 variants with enhanced InsP(6) sensitivity rescues the mRNA export defect of the ipk1 (inositol 1,3,4,5,6-pentakisphosphate 2-kinase) InsP(6)-deficient mutant and, furthermore, significantly improves vegetative growth, seed yield, and seed performance of the mutant. These results suggest that Gle1 is an important factor responsible for mediating InsP(6) functions in plant growth and reproduction and that Gle1 variants with increased InsP(6) sensitivity may be useful for engineering high-yielding low-phytate crops.

  5. Copper exposure induces oxidative injury, disturbs the antioxidant system and changes the Nrf2/ARE (CuZnSOD) signaling in the fish brain: protective effects of myo-inositol.

    PubMed

    Jiang, Wei-Dan; Liu, Yang; Hu, Kai; Jiang, Jun; Li, Shu-Hong; Feng, Lin; Zhou, Xiao-Qiu

    2014-10-01

    The brain is the center of the nervous system in all vertebrates, and homeostasis of the brain is crucial for fish survival. Copper (Cu) is essential for normal cellular processes in most eukaryotic organisms but is toxic in excess. Although Cu is indicated as a potent neurotoxicant, information regarding its threat to fish brain and underlying mechanisms is still scarce. In accordance, the objective of this study was to assess the effects and the potential mechanism of Cu toxicity by evaluating brain oxidative status, the enzymatic and mRNA levels of antioxidant genes, as well as the Nrf2/ARE signaling in the brain of fish after Cu exposure. The protective effects of myo-inositol (MI) against subsequent Cu exposure were also investigated. The results indicate that induction of oxidative stress by Cu is shown by increases in brain ROS production, lipid peroxidation and protein oxidation, which are accompanied by depletions of antioxidants, including total superoxide dismutase (T-SOD), CuZnSOD, glutathione-S-transferase (GST) and glutathione reductase (GR) activities and glutathione (GSH) content. Cu exposure increased the catalase (CAT) and glutathione peroxidase (GPx) activities. Further molecular results showed that Cu exposure up-regulated CuZnSOD, GPx1a and GR mRNA levels, suggesting an adaptive mechanism against stress. Moreover, Cu exposure increased fish brain Nrf2 nuclear accumulation and increased its ability of binding to ARE (CuZnSOD), which supported the increased CuZnSOD mRNA levels. In addition, Cu exposure caused increases of the expression of the Nrf2, Maf G1 (rather than Maf G2 gene) and PKCd genes, suggesting that de novo synthesis of those factors is required for the protracted induction of such antioxidant genes. However, the modulation of Keap1a (rather than Keap1b) of fish brain under Cu exposure might be used to turn off of the signaling cascade and avoid harmful effects. Interestingly, pre-treatment of fish with MI prevented the fish brain

  6. The oxygen isotope composition of phosphate released from phytic acid by the activity of wheat and Aspergillus niger phytase

    NASA Astrophysics Data System (ADS)

    von Sperber, C.; Tamburini, F.; Brunner, B.; Bernasconi, S. M.; Frossard, E.

    2015-07-01

    Phosphorus (P) is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inorganic phosphate (Pi) from organic phosphorus compounds (Porg). Phytic acid (myo-inositol hexakisphosphate, IP6) is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields available Pi and less phosphorylated inositol derivates as products. The hydrolysis of organic P compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O) of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'-monophosphate (AMP) and glycerophosphate (GPO4) as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as a substrate were prepared. During the hydrolysis of IP6 by phytase, four of the six Pi were released, and one oxygen atom from water was incorporated into each Pi. This incorporation of oxygen from water into Pi was subject to an apparent inverse isotopic fractionation (ϵ ~ 6 to 10 ‰), which was similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (ϵ ~ 7 ‰), where less than three Pi were released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (ϵ ~ -12 ‰), similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in ϵ to the same amino acid sequence motif (RHGXRXP) at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking

  7. Isolation and characterization of esters of indole-3-acetic acid from the liquid endosperm of the horse chestnut (Aesculus species)

    NASA Technical Reports Server (NTRS)

    Domagalski, W.; Schulze, A.; Bandurski, R. S.

    1987-01-01

    Esters of indole-3-acetic acid were extracted and purified from the liquid endosperm of immature fruits of various species of the horse chestnut (Aesculus parviflora, A. baumanni, A. pavia rubra, and A. pavia humulis). The liquid endosperm contained, at least 12 chromatographically distinct esters. One of these compounds was purified and characterized as an ester of indole-3-acetic acid and myo-inositol. A second compound was found to be an ester of indole-3-acetic acid and the disaccharide rutinose (glucosyl-rhamnose). A third compound was partially characterized as an ester of indole-3-acetic acid and a desoxyaminohexose.

  8. Mutations of the multi-drug resistance-associated protein ABC transporter gene 5 result in reduction of phytic acid in rice seeds.

    PubMed

    Xu, Xiu-Hong; Zhao, Hai-Jun; Liu, Qing-Long; Frank, Thomas; Engel, Karl-Heinz; An, Gynheung; Shu, Qing-Yao

    2009-06-01

    Phytic acid (PA, myo-inositol 1,2,3,4,5,6-hexakisphosphate) is important to the nutritional quality of cereal and legume seeds. PA and its salts with micronutrient cations, such as iron and zinc, cannot be digested by humans and non-ruminant animals, and hence may affect food/feed nutritional value and cause P pollution of groundwater from animal waste. We previously developed a set of low phytic acid (LPA) rice mutant lines with the aim of increasing the nutritional quality of rice. Two of these lines, Os-lpa-XS110-2 (homozygous non-lethal) Os-lpa-XS110-3 (homozygous lethal), contain two mutant alleles of a LPA gene (hereafter XS-lpa2-1 and XS-lpa2-2, respectively). In this study, we mapped the XS-lpa2-1 gene to a region on chromosome 3 between microsatellite markers RM14360 and RM1332, where the rice orthologue (OsMRP5) of the maize lpa1 gene is located. Sequence analysis of the OsMRP5 gene revealed a single base pair change (C/G-T/A transition) in the sixth exon of XS-lpa2-1 and a 5-bp deletion in the first exon of XS-lpa2-2. OsMRP5 is expressed in both vegetative tissues and developing seeds, and the two mutations do not change the level of RNA transcription. A T-DNA insertion line, 4A-02500, in which OsMRP5 was disrupted, also showed the same high inorganic phosphorus phenotype as Os-lpa-XS110-3 and appeared to be homozygous lethal. PA is significantly reduced in Os-lpa-XS110-2 (~20%) and in 4A-02500 (~90%) seeds compared with their wild type lines, and no PA was detected in Os-lpa-XS110-3 using HPLC analysis. This evidence indicates that the OsMRP5 gene plays an important role in PA metabolism in rice seeds.

  9. Phytate degradation by lactic acid bacteria and yeasts during the wholemeal dough fermentation: a 31P NMR study.

    PubMed

    Reale, Anna; Mannina, Luisa; Tremonte, Patrizio; Sobolev, Anatoli P; Succi, Mariantonietta; Sorrentino, Elena; Coppola, Raffaele

    2004-10-06

    myo-Inositol hexaphosphate (IP6) is the main source of phosphorus in cereal grains, and therefore, in bakery products. Different microorganisms such as yeasts and lactic acid bacteria have phytase enzymes able to hydrolyze IP6 during the wholemeal breadmaking. In this paper, the phytase activity of Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus curvatus, and Saccharomyces cerevisiae strains, isolated from southern Italian sourdoughs, is assayed using the (31)P NMR technique. The sourdough technology based on the use of lactic acid bacteria in the breadmaking is finally suggested.

  10. Absence of detectable inositol hexakisphosphate (phytate) in plasma.

    PubMed

    Irvine, Robin F

    2014-06-01

    A critical evaluation of a recent attempt to measure inositol hexakisphosphate (IP6) in mammalian plasma by mass spectroscopy leads to the conclusion that as yet there is no unambiguous evidence that plasma contains any IP6.

  11. Application of HPLC for determination of phytic acid in the colonic epithelial Caco-2 cells.

    PubMed

    Weglarz, Ludmiła; Parfiniewicz, Beata; Bat, Beata; Orchel, Arkadiusz; Dzierzewicz, Zofia; Wilczok, Tadeusz

    2004-12-01

    Phytic acid (myo-inositol hexaphosphate, IP6) is currently receiving a considerable interest because of its anticancer (preventive and therapeutic) potential against colon tumors and the need for methods of its determination. The aim of this study was to analyze the uptake of IP6 by human colon adenocarcinoma cells (Caco-2 cell line) and to evaluate the method of its intracellular quantification with the use of high performance liquid chromatography (HPLC) technique. Chromatographic analysis revealed a rapid uptake of IP6 by cells. The intracellular accumulation of IP6 was saturable at 0.5 h and it did not change with the prolongation of incubation up to 72 h.

  12. Effects of inositol, inositol-generating phytase B applied alone, and in combination with 6-phytase A to phosphorus-deficient diets on laying performance, eggshell quality, yolk cholesterol, and fatty acid deposition in laying hens.

    PubMed

    Zyla, K; Mika, M; Duliński, R; Swiatkiewicz, S; Koreleski, J; Pustkowiak, H; Piironen, J

    2012-08-01

    Phytase B, a product of Aspergillus niger phyB gene expressed in Trichoderma reesei, which increased myo-inositol concentrations in 20 mM sodium phytate solution 7.5-fold during 120-min incubation, a combination of phytase B with 6-phytase A, and pure myo-inositol were tested as feed supplements in Bovans Brown laying hens. In the 2-factorial experiment (2×5), birds from wk 50 to 62 were fed 2 basal diets, corn-soybean (CSM) or wheat-soybean (WSM), using 12 one-hen cages per treatment. For both basal diets, the dietary treatments included negative control (0.08% nonphytate P in CSM, 0.13% nonphytate P in WSM; NC); internal control groups, NC+0.04% nonphytate P from monocalcium phosphate, MCP (IC); NC+0.1% of myo-inositol (Inos), NC+phytase B at 1,300 units of phytase B-acid phosphatase activity (AcPU)/kg (PhyB), NC+phytase B at 1,300 AcPU/kg+6-phytase A at 300 FTU/kg (PhyA+B). Feed intake, laying performance, and eggshell quality were determined. The total lipid and cholesterol contents as well as fatty acid profile were assessed in egg yolks collected from hens fed CSM diets, as was fatty acid profile. The hens fed the WSM diet consumed significantly more feed, laid a higher mass of eggs daily with higher mean weights, and had a higher hen-day egg production than the birds receiving the CSM diets. Similarly, higher values for yolk weights, shell weights, shell thickness, shell density, and breaking strengths were determined in the eggs laid by the hens fed the WSM diets. In hens fed either the CSM diets with phytase B alone, or in combination with 6-phytase A, enhanced feed intakes, egg mass, and hen-day egg production were recorded. Phytases also enhanced the eggshell quality parameters in the hens fed both variants of the diets. Phytase B alone, or in combination with 6-phytase A, reduced the total lipid and cholesterol concentrations in egg yolks collected from the hens fed the CSM diets, whereas the combination of both phytases improved the n-6:n-3

  13. Impacts of dietary calcium, phytate, and nonphytate phosphorus concentrations in the presence or absence of phytase on inositol hexakisphosphate (IP6) degradation in different segments of broilers digestive tract.

    PubMed

    Li, W; Angel, R; Kim, S-W; Brady, K; Yu, S; Plumstead, P W

    2016-03-01

    A total of 1,440 straight-run Heritage 56M × fast-feathering Cobb 500F broiler birds were fed from 11 to 13 d of age to determine the impacts of calcium (Ca), phytate phosphorus (PP), nonphytate P (NPP) and phytase concentrations on the myo-inositol hexakisphosphate (IP6) flow through the different parts of gastrointestinal tract (GIT). The experiment was a 2×2×2×3 randomized block design with 2 Ca (0.7 and 1.0%), 2 PP (0.23 and 0.34%), 2 nPP (0.28 and 0.45%) and 3 phytase (0-, 500-, and 1,000-phytase unit (FTU)/kg) concentrations. The experiment was replicated twice (block) with 3 replicates per treatment (TRT) of 10 birds per block. Concentration of IP6 in crop, proventriculus (PROV) plus (+) gizzard (GIZ) and distal ileum digesta as well as the ileal IP6 disappearance was determined at 13 d of age. In crop, higher IP6 concentration was seen with increased Ca (P < 0.05). Despite the interaction between PP and phytase, higher dietary PP led to greater IP6 concentration (P < 0.05). Similar main effects of PP and phytase were also seen in Prov+Giz and ileum (P < 0.05) without interactions. Interaction between Ca and nPP on IP6 concentration was seen in Prov+Giz (P < 0.05). Decreased ileal IP6 disappearance was found at higher Ca (62.3% at 0.7% Ca vs. 57.5% at 1.0% Ca; P < 0.05). In general, adding phytase improved IP6 degradation but the degree of impact was dependent on nPP and PP (P < 0.05). In conclusion, phytase inclusion significantly reduced IP6 concentration and IP6 disappearance in distal ileum regardless of GIT segments or diet composition, but impacts of dietary Ca, nPP, and PP differed depending on GIT segment examined.

  14. Impacts of dietary calcium, phytate, and nonphytate phosphorus concentrations in the presence or absence of phytase on inositol hexakisphosphate (IP6) degradation in different segments of broilers digestive tract

    PubMed Central

    Li, W.; Angel, R.; Kim, S.-W.; Brady, K.; Yu, S.; Plumstead, P. W.

    2016-01-01

    A total of 1,440 straight-run Heritage 56M × fast-feathering Cobb 500F broiler birds were fed from 11 to 13 d of age to determine the impacts of calcium (Ca), phytate phosphorus (PP), nonphytate P (nPP) and phytase concentrations on the myo-inositol hexakisphosphate (IP6) flow through the different parts of gastrointestinal tract (GIT). The experiment was a 2×2×2×3 randomized block design with 2 Ca (0.7 and 1.0%), 2 PP (0.23 and 0.34%), 2 nPP (0.28 and 0.45%) and 3 phytase (0-, 500-, and 1,000-phytase unit (FTU)/kg) concentrations. The experiment was replicated twice (block) with 3 replicates per treatment (Trt) of 10 birds per block. Concentration of IP6 in crop, proventriculus (Prov) plus (+) gizzard (Giz) and distal ileum digesta as well as the ileal IP6 disappearance was determined at 13 d of age. In crop, higher IP6 concentration was seen with increased Ca (P < 0.05). Despite the interaction between PP and phytase, higher dietary PP led to greater IP6 concentration (P < 0.05). Similar main effects of PP and phytase were also seen in Prov+Giz and ileum (P < 0.05) without interactions. Interaction between Ca and nPP on IP6 concentration was seen in Prov+Giz (P < 0.05). Decreased ileal IP6 disappearance was found at higher Ca (62.3% at 0.7% Ca vs. 57.5% at 1.0% Ca; P < 0.05). In general, adding phytase improved IP6 degradation but the degree of impact was dependent on nPP and PP (P < 0.05). In conclusion, phytase inclusion significantly reduced IP6 concentration and IP6 disappearance in distal ileum regardless of GIT segments or diet composition, but impacts of dietary Ca, nPP, and PP differed depending on GIT segment examined. PMID:26740131

  15. Effect of nitrogen deficiency on ascorbic acid biosynthesis and recycling pathway in cucumber seedlings.

    PubMed

    Zhang, Xue; Yu, Hong Jun; Zhang, Xiao Meng; Yang, Xue Yong; Zhao, Wen Chao; Li, Qiang; Jiang, Wei Jie

    2016-11-01

    L-Ascorbic acid (AsA, ascorbate) is one of the most abundant natural antioxidants, and it is an important factor in the nutritional quality of cucumber. In this work, key enzymes involved in the ascorbic acid biosynthesis and recycling pathway in cucumber seedlings under nitrogen deficiency were investigated at the levels of transcription and enzyme activity. The activities of myo-inositol oxygenase (MIOX) and transcript levels of MIOXs increased dramatically, while the activities of ascorbate oxidase (AO) and glutathione reductase (GR) and transcript levels of AOs and GR2 decreased significantly in N-limited leaves, as did the ascorbate concentration, in nitrogen-deficient cucumber seedlings. The activities of other enzymes and transcript levels of other genes involved in the ascorbate recycling pathway and ascorbate synthesis pathways decreased or remained unchanged under nitrogen deficiency. These results indicate that nitrogen deficiency induced genes involved in the ascorbate-glutathione recycling and myo-inositol pathway in cucumber leaves. Thus, the AO, GR and MIOX involved in the pathways might play roles in AsA accumulation.

  16. Down-regulation of UDP-glucuronic Acid Biosynthesis Leads to Swollen Plant Cell Walls and Severe Developmental Defects Associated with Changes in Pectic Polysaccharides*

    PubMed Central

    Reboul, Rebecca; Geserick, Claudia; Pabst, Martin; Frey, Beat; Wittmann, Doris; Lütz-Meindl, Ursula; Léonard, Renaud; Tenhaken, Raimund

    2011-01-01

    UDP-glucose dehydrogenase (UGD) plays a key role in the nucleotide sugar biosynthetic pathway, as its product UDP-glucuronic acid is the common precursor for arabinose, xylose, galacturonic acid, and apiose residues found in the cell wall. In this study we characterize an Arabidopsis thaliana double mutant ugd2,3 that lacks two of the four UGD isoforms. This mutant was obtained from a cross of ugd2 and ugd3 single mutants, which do not show phenotypical differences compared with the WT. In contrast, ugd2,3 has a strong dwarfed phenotype and often develops seedlings with severe root defects suggesting that the UGD2 and UGD3 isoforms act in concert. Differences in its cell wall composition in comparison to the WT were determined using biochemical methods indicating a significant reduction in arabinose, xylose, apiose, and galacturonic acid residues. Xyloglucan is less substituted with xylose, and pectins have a reduced amount of arabinan side chains. In particular, the amount of the apiose containing side chains A and B of rhamnogalacturonan II is strongly reduced, resulting in a swollen cell wall. The alternative pathway to UDP-glucuronic acid with the key enzyme myo-inositol oxygenase is not up-regulated in ugd2,3. The pathway also does not complement the ugd2,3 mutation, likely because the supply of myo-inositol is limited. Taken together, the presented data underline the importance of UDP GlcA for plant primary cell wall formation. PMID:21949134

  17. Down-regulation of UDP-glucuronic acid biosynthesis leads to swollen plant cell walls and severe developmental defects associated with changes in pectic polysaccharides.

    PubMed

    Reboul, Rebecca; Geserick, Claudia; Pabst, Martin; Frey, Beat; Wittmann, Doris; Lütz-Meindl, Ursula; Léonard, Renaud; Tenhaken, Raimund

    2011-11-18

    UDP-glucose dehydrogenase (UGD) plays a key role in the nucleotide sugar biosynthetic pathway, as its product UDP-glucuronic acid is the common precursor for arabinose, xylose, galacturonic acid, and apiose residues found in the cell wall. In this study we characterize an Arabidopsis thaliana double mutant ugd2,3 that lacks two of the four UGD isoforms. This mutant was obtained from a cross of ugd2 and ugd3 single mutants, which do not show phenotypical differences compared with the WT. In contrast, ugd2,3 has a strong dwarfed phenotype and often develops seedlings with severe root defects suggesting that the UGD2 and UGD3 isoforms act in concert. Differences in its cell wall composition in comparison to the WT were determined using biochemical methods indicating a significant reduction in arabinose, xylose, apiose, and galacturonic acid residues. Xyloglucan is less substituted with xylose, and pectins have a reduced amount of arabinan side chains. In particular, the amount of the apiose containing side chains A and B of rhamnogalacturonan II is strongly reduced, resulting in a swollen cell wall. The alternative pathway to UDP-glucuronic acid with the key enzyme myo-inositol oxygenase is not up-regulated in ugd2,3. The pathway also does not complement the ugd2,3 mutation, likely because the supply of myo-inositol is limited. Taken together, the presented data underline the importance of UDP GlcA for plant primary cell wall formation.

  18. Degradation of phytate by the 6-phytase from Hafnia alvei: a combined structural and solution study.

    PubMed

    Ariza, Antonio; Moroz, Olga V; Blagova, Elena V; Turkenburg, Johan P; Waterman, Jitka; Roberts, Shirley M; Vind, Jesper; Sjøholm, Carsten; Lassen, Søren F; De Maria, Leonardo; Glitsoe, Vibe; Skov, Lars K; Wilson, Keith S

    2013-01-01

    Phytases hydrolyse phytate (myo-inositol hexakisphosphate), the principal form of phosphate stored in plant seeds to produce phosphate and lower phosphorylated myo-inositols. They are used extensively in the feed industry, and have been characterised biochemically and structurally with a number of structures in the PDB. They are divided into four distinct families: histidine acid phosphatases (HAP), β-propeller phytases, cysteine phosphatases and purple acid phosphatases and also split into three enzyme classes, the 3-, 5- and 6-phytases, depending on the position of the first phosphate in the inositol ring to be removed. We report identification, cloning, purification and 3D structures of 6-phytases from two bacteria, Hafnia alvei and Yersinia kristensenii, together with their pH optima, thermal stability, and degradation profiles for phytate. An important result is the structure of the H. alvei enzyme in complex with the substrate analogue myo-inositol hexakissulphate. In contrast to the only previous structure of a ligand-bound 6-phytase, where the 3-phosphate was unexpectedly in the catalytic site, in the H. alvei complex the expected scissile 6-phosphate (sulphate in the inhibitor) is placed in the catalytic site.

  19. Degradation of Phytate by the 6-Phytase from Hafnia alvei: A Combined Structural and Solution Study

    PubMed Central

    Blagova, Elena V.; Turkenburg, Johan P.; Waterman, Jitka; Roberts, Shirley M.; Vind, Jesper; Sjøholm, Carsten; Lassen, Søren F.; De Maria, Leonardo; Glitsoe, Vibe; Skov, Lars K.; Wilson, Keith S.

    2013-01-01

    Phytases hydrolyse phytate (myo-inositol hexakisphosphate), the principal form of phosphate stored in plant seeds to produce phosphate and lower phosphorylated myo-inositols. They are used extensively in the feed industry, and have been characterised biochemically and structurally with a number of structures in the PDB. They are divided into four distinct families: histidine acid phosphatases (HAP), β-propeller phytases, cysteine phosphatases and purple acid phosphatases and also split into three enzyme classes, the 3-, 5- and 6-phytases, depending on the position of the first phosphate in the inositol ring to be removed. We report identification, cloning, purification and 3D structures of 6-phytases from two bacteria, Hafnia alvei and Yersinia kristensenii, together with their pH optima, thermal stability, and degradation profiles for phytate. An important result is the structure of the H. alvei enzyme in complex with the substrate analogue myo-inositol hexakissulphate. In contrast to the only previous structure of a ligand-bound 6-phytase, where the 3-phosphate was unexpectedly in the catalytic site, in the H. alvei complex the expected scissile 6-phosphate (sulphate in the inhibitor) is placed in the catalytic site. PMID:23741456

  20. Phytate (myo-inositol hexaphosphate) and risk factors for osteoporosis.

    PubMed

    López-González, A A; Grases, F; Roca, P; Mari, B; Vicente-Herrero, M T; Costa-Bauzá, A

    2008-12-01

    Several risk factors seem to play a role in the development of osteoporosis. Phytate is a naturally occurring compound that is ingested in significant amounts by those with diets rich in whole grains. The aim of this study was to evaluate phytate consumption as a risk factor in osteoporosis. In a first group of 1,473 volunteer subjects, bone mineral density was determined by means of dual radiological absorptiometry in the calcaneus. In a second group of 433 subjects (used for validation of results obtained for the first group), bone mineral density was determined in the lumbar column and the neck of the femur. Subjects were individually interviewed about selected osteoporosis risk factors. Dietary information related to phytate consumption was acquired by questionnaires conducted on two different occasions, the second between 2 and 3 months after performing the first one. One-way analysis of variance or Student's t test was used to determine statistical differences between groups. Bone mineral density increased with increasing phytate consumption. Multivariate linear regression analysis indicated that body weight and low phytate consumption were the risk factors with greatest influence on bone mineral density. Phytate consumption had a protective effect against osteoporosis, suggesting that low phytate consumption should be considered an osteoporosis risk factor.

  1. Methyl-inositol, γ-aminobutyric acid and other health benefit compounds in the aril of litchi.

    PubMed

    Wu, Zi-Chen; Yang, Zhuan-Ying; Li, Jian-Guo; Chen, Hou-Bin; Huang, Xu-Ming; Wang, Hui-Cong

    2016-11-01

    The available components in the flesh of litchi seem insufficient to interpret its wide and significant physiological effects. Some unusual compounds, including myo-inositol, inositol methyl derivatives and γ-aminobutyric acid (GABA) were identified as main constituents in the flesh of litchi. Their concentrations varied among cultivars but remain relatively constant during development. Litchi flesh was shown to contain moderate myo-inositol (0.28-0.78 mg g(-1) FW), ascorbic acid (0.08-0.39 mg g(-1) FW) and phenolics (0.47-1.60 mg g(-1) FW), but abundant l-quebrachitol (1.6-6.4 mg g(-1) FW) and GABA (1.7-3.5 mg g(-1) FW). The concentration of GABA in the flesh of litchi was about 100 times higher than in other fruits. And l-quebrachitol is not a common component in fruits. The biological and physiological activities of inositols, inositol derivatives and GABA have been extensively documented. These compounds are probably important compositional characteristic contributing to the widely shown health benefits of litchi.

  2. Expression, gene cloning, and characterization of five novel phytases from four basidiomycete fungi: Peniophora lycii, Agrocybe pediades, a Ceriporia sp., and Trametes pubescens.

    PubMed

    Lassen, S F; Breinholt, J; Østergaard, P R; Brugger, R; Bischoff, A; Wyss, M; Fuglsang, C C

    2001-10-01

    Phytases catalyze the hydrolysis of phosphomonoester bonds of phytate (myo-inositol hexakisphosphate), thereby creating lower forms of myo-inositol phosphates and inorganic phosphate. In this study, cDNA expression libraries were constructed from four basidiomycete fungi (Peniophora lycii, Agrocybe pediades, a Ceriporia sp., and Trametes pubescens) and screened for phytase activity in yeast. One full-length phytase-encoding cDNA was isolated from each library, except for the Ceriporia sp. library where two different phytase-encoding cDNAs were found. All five phytases were expressed in Aspergillus oryzae, purified, and characterized. The phytases revealed temperature optima between 40 and 60 degrees C and pH optima at 5.0 to 6.0, except for the P. lycii phytase, which has a pH optimum at 4.0 to 5.0. They exhibited specific activities in the range of 400 to 1,200 U. mg, of protein(-1) and were capable of hydrolyzing phytate down to myo-inositol monophosphate. Surprisingly, (1)H nuclear magnetic resonance analysis of the hydrolysis of phytate by all five basidiomycete phytases showed a preference for initial attack at the 6-phosphate group of phytic acid, a characteristic that was believed so far not to be seen with fungal phytases. Accordingly, the basidiomycete phytases described here should be grouped as 6-phytases (EC 3.1.3.26).

  3. Inositol hexakisphosphate kinase products contain diphosphate and triphosphate groups.

    PubMed

    Draskovic, Petra; Saiardi, Adolfo; Bhandari, Rashna; Burton, Adam; Ilc, Gregor; Kovacevic, Miroslav; Snyder, Solomon H; Podobnik, Marjetka

    2008-03-01

    Eukaryotic cells produce a family of diverse inositol polyphosphates (IPs) containing pyrophosphate bonds. Inositol pyrophosphates have been linked to a wide range of cellular functions, and there is growing evidence that they act as second messengers. Inositol hexakisphosphate kinase (IP6K) is able to convert the natural substrates inositol pentakisphosphate (IP 5) and inositol hexakisphosphate (IP 6) to several products with an increasing number of phospho-anhydride bonds. In this study, we structurally analyzed IPs synthesized by three mammalian isoforms of IP6K from IP 5 and IP 6. The NMR and mass analyses showed a number of products with diverse, yet specific, stereochemistry, defined by the architecture of IP6K's active site. We now report that IP6K synthesizes both pyrophosphate (diphospho) as well as triphospho groups on the inositol ring. All three IP6K isoforms share the same activities both in vitro and in vivo.

  4. Inositol hexakisphosphate is bound in the ADAR2 core and required for RNA editing.

    PubMed

    Macbeth, Mark R; Schubert, Heidi L; Vandemark, Andrew P; Lingam, Arunth T; Hill, Christopher P; Bass, Brenda L

    2005-09-02

    We report the crystal structure of the catalytic domain of human ADAR2, an RNA editing enzyme, at 1.7 angstrom resolution. The structure reveals a zinc ion in the active site and suggests how the substrate adenosine is recognized. Unexpectedly, inositol hexakisphosphate (IP6) is buried within the enzyme core, contributing to the protein fold. Although there are no reports that adenosine deaminases that act on RNA (ADARs) require a cofactor, we show that IP6 is required for activity. Amino acids that coordinate IP6 in the crystal structure are conserved in some adenosine deaminases that act on transfer RNA (tRNA) (ADATs), related enzymes that edit tRNA. Indeed, IP6 is also essential for in vivo and in vitro deamination of adenosine 37 of tRNAala by ADAT1.

  5. Metabolite profiling of two low phytic acid (lpa) rice mutants.

    PubMed

    Frank, Thomas; Meuleye, Bertrand Seumo; Miller, Andreas; Shu, Qing-Yao; Engel, Karl-Heinz

    2007-12-26

    Two low phytic acid (lpa) rice mutant lines, Os-lpa-XS110-1 and Os-lpa-XS110-2, were grown together with their parent wild-type variety Xiushui 110 in four field trials. HPLC analysis of inositol phosphates in the seeds produced demonstrated that compared to the wild-type, the reduction in phytic acid content in Os-lpa-XS110-1 (-46%) was more pronounced than that in Os-lpa-XS110-2 (-23%). Lower inositol phosphates (InsP 3, InsP 4, InsP 5) were not detected in the mutants. The lpa mutants and the wild-type rice were subjected to comparative metabolite profiling by capillary gas chromatography. On average, 34% (Os-lpa-XS110-1) and 42% (Os-lpa-XS110-2) of the detected peaks were statistically significantly different between wild-type and mutants. However, only a few of these differences could be consistently observed for all field trials. Identification and quantification of the consistently different metabolites revealed that contents of myo-inositol and raffinose were increased in Os-lpa-XS110-1 but decreased in Os-lpa-XS110-2 compared to the wild-type. In addition, Os-lpa-XS110-1 exhibited increased levels of galactose and galactinol. Consideration of these metabolic changes in light of the routes involved in the biosynthesis of phytic acid indicated a disturbance in the early biosynthetic pathway of phytic acid in Os-lpa-XS110-2 (similar to the lpa-1 type mutation in maize) and a mutation event affecting phosphorylation of myo-inositol in Os-lpa-XS110-1 (similar to the lpa-3-type mutation).

  6. Protective effect of phytic acid hydrolysis products on iron-induced lipid peroxidation of liposomal membranes.

    PubMed

    Miyamoto, S; Kuwata, G; Imai, M; Nagao, A; Terao, J

    2000-12-01

    Beneficial effects of dietary phytic acid (myo-inositol hexaphosphate; IP6) have often been explained by its strong iron ion-chelating ability, which possibly suppresses iron ion-induced oxidative damage in the gastrointestinal tract. Because phytic acid is hydrolyzed during digestion, this work aimed to know whether its hydrolysis products (IP2, IP3, IP4, and IP5) could still prevent iron ion-induced lipid peroxidation. Studies using liposomal membranes demonstrated that hydrolysis products containing three or more phosphate groups are able to inhibit iron ion-induced lipid peroxidation although their effectiveness decreased with dephosphorylation. Similarly, they also prevented iron ion-induced decomposition of phosphatidylcholine hydroperoxide. These results demonstrate that intermediate products of phytic acid hydrolysis still possess iron ion-chelating ability, and thus they can probably prevent iron ion-induced lipid peroxidation in biological systems.

  7. A conserved family of enzymes that phosphorylate inositol hexakisphosphate.

    PubMed

    Mulugu, Sashidhar; Bai, Wenli; Fridy, Peter C; Bastidas, Robert J; Otto, James C; Dollins, D Eric; Haystead, Timothy A; Ribeiro, Anthony A; York, John D

    2007-04-06

    Inositol pyrophosphates are a diverse group of high-energy signaling molecules whose cellular roles remain an active area of study. We report a previously uncharacterized class of inositol pyrophosphate synthase and find it is identical to yeast Vip1 and Asp1 proteins, regulators of actin-related protein-2/3 (ARP 2/3) complexes. Vip1 and Asp1 acted as enzymes that encode inositol hexakisphosphate (IP6) and inositol heptakisphosphate (IP7) kinase activities. Alterations in kinase activity led to defects in cell growth, morphology, and interactions with ARP complex members. The functionality of Asp1 and Vip1 may provide cells with increased signaling capacity through metabolism of IP6.

  8. Metabolite profiling of two novel low phytic acid (lpa) soybean mutants.

    PubMed

    Frank, Thomas; Nörenberg, Svenja; Engel, Karl-Heinz

    2009-07-22

    A GC-based approach was applied to compare the metabolite profiles of two low phytic acid (lpa) soybean mutants and their respective wild-types. The lpa mutants (Gm-lpa-TW75-1 and Gm-lpa-ZC-2) were grown together with the wild-types (Taiwan 75 and Zhechun no. 3) in three and four field trials, respectively. HPLC analysis revealed a phytic acid reduction of -53% for Gm-lpa-TW75-1 and of -46% for Gm-lpa-ZC-2. For Gm-lpa-TW75-1, no accumulation of lower inositol phosphates was observed, whereas Gm-lpa-ZC-2 exhibited significantly increased contents of the lower inositol phosphates InsP(3), InsP(4), and InsP(5) compared to the corresponding wild-type. The metabolite profiling revealed that compared to the wild-types, 40% (Gm-lpa-TW75-1) and 21% (Gm-lpa-ZC-2) of the detected peaks were statistically significantly different in the lpa mutants grown at one field trial. However, the majority of these differences were shown to be related to environmental impact and natural variability rather than to the mutation event. Identification of consistent metabolic changes in the lpa mutants revealed decreased contents of myo-inositol, galactinol, raffinose, stachyose, and the galactosyl cyclitols galactopinitol A, galactopinitol B, and fagopyritol B1 compared to the wild-type. These consistently pronounced changes in Gm-lpa-TW75-1 confirmed the suggested mutation target. Consideration of the metabolic changes observed for Gm-lpa-ZC-2 (accumulation of lower inositol phosphates and increased myo-inositol contents) indicated a mutation event affecting the latter biosynthetic steps leading to phytic acid. The study demonstrated the applicability of metabolite profiling for the detection of changes in the metabolite phenotype induced by mutation breeding and its power in assisting in the elucidation of mutation events.

  9. Inframolecular acid–base and coordination properties towards Na+ and Mg2+ of myo-inositol 1,3,4,5,6-pentakisphosphate: a structural approach to biologically relevant species† †Electronic supplementary information (ESI) available: Application of the Cluster Expansion Method (Table S1); 31P NMR spectra (Fig. S1); Structural details of Ins(1,3,4,5,6)P 5–Mg2+ interaction (Fig. S2); Comparative fit of alternative chemical models for the Ins(1,3,4,5,6)P 5–Na+ system (Fig. S3). See DOI: 10.1039/c2dt31807e Click here for additional data file.

    PubMed Central

    Torres, Julia; Macho, Israel; Gómez, Kerman; Godage, Himali Y.; Riley, Andrew M.; Potter, Barry V. L.; González, Gabriel; Kremer, Carlos

    2013-01-01

    The myo-inositol phosphates (InsPs) are specific signalling metabolites ubiquitous in eukaryotic cells. Although Ins(1,3,4,5,6)P 5 is the second most abundant member of the InsPs family, its certain biological roles are far from being elucidated, in part due to the large number of species formed by Ins(1,3,4,5,6)P 5 in the presence of metal ions. In light of this, we have strived in the past to make a complete and at the same time “biological-user-friendly” description of the Ins(1,3,4,5,6)P 5 chemistry with mono and multivalent cations. In this work we expand these studies focusing on the inframolecular aspects of its protonation equilibria and the microscopic details of its coordination behaviour towards biologically relevant metal ions. We present here a systematic study of the Ins(1,3,4,5,6)P 5 intrinsic acid–base processes, in a non-interacting medium, and over a wide pH range, analyzing the 31P NMR curves by means of a model based on the Cluster Expansion Method. In addition, we have used a computational approach to analyse the energetic and structural features of the protonation and conformational changes of Ins(1,3,4,5,6)P 5, and how they are influenced by the presence of two physiologically relevant cations, Na+ and Mg2+. PMID:23183928

  10. Inositol Hexakisphosphate Kinase 3 Regulates Metabolism and Lifespan in Mice

    PubMed Central

    Moritoh, Yusuke; Oka, Masahiro; Yasuhara, Yoshitaka; Hozumi, Hiroyuki; Iwachidow, Kimihiko; Fuse, Hiromitsu; Tozawa, Ryuichi

    2016-01-01

    Inositol hexakisphosphate kinase 3 (IP6K3) generates inositol pyrophosphates, which regulate diverse cellular functions. However, little is known about its own physiological role. Here, we show the roles of IP6K3 in metabolic regulation. We detected high levels of both mouse and human IP6K3 mRNA in myotubes and muscle tissues. In human myotubes, IP6K3 was upregulated by dexamethasone treatment, which is known to inhibit glucose metabolism. Furthermore, Ip6k3 expression was elevated under diabetic, fasting, and disuse conditions in mouse skeletal muscles. Ip6k3−/− mice demonstrated lower blood glucose, reduced circulating insulin, deceased fat mass, lower body weight, increased plasma lactate, enhanced glucose tolerance, lower glucose during an insulin tolerance test, and reduced muscle Pdk4 expression under normal diet conditions. Notably, Ip6k3 deletion extended animal lifespan with concomitant reduced phosphorylation of S6 ribosomal protein in the heart. In contrast, Ip6k3−/− mice showed unchanged skeletal muscle mass and no resistance to the effects of high fat diet. The current observations suggest novel roles of IP6K3 in cellular regulation, which impact metabolic control and lifespan. PMID:27577108

  11. A femtomole-sensitivity mass assay for inositol hexakisphosphate.

    PubMed

    Letcher, Andrew J; Schell, Michael J; Irvine, Robin F

    2010-01-01

    Inositol hexakisphosphate (InsP(6)) is an important component of cells, and its mass levels are usually assayed by either (a) equilibrium labelling of cell cultures with radiolabelled inositol or (b) by a variety of mass assays of differing sensitivities and ambiguities. Here, we describe a mass assay for InsP(6) that is based on phosphorylating InsP(6) with [(32)P]-ATP to 5-(PP)InsP(5) using a recombinant Giardia InsP(6) kinase and quantification of the radiolabelled 5-[(32)P](PP)InsP(5) product by anion exchange HPLC with an internal [(3)H]-(PP)InsP(5) standard. Interference with the enzyme reaction by other factors in the tissue extract is corrected for by assay of identical aliquots of tissue spiked with known amounts of InsP(6). This assay only measures InsP(6) (and not other inositol phosphates), and although it is simple in principle and requires no dedicated or specialised equipment, it is quite time-consuming. But the assay is unambiguous and is capable of quantifying accurately as little as 10 fmol of InsP(6) in a cell extract.

  12. Differential transcriptional regulation of L-ascorbic acid content in peel and pulp of citrus fruits during development and maturation.

    PubMed

    Alós, Enriqueta; Rodrigo, María J; Zacarías, Lorenzo

    2014-05-01

    Citrus fruits are an important source of ascorbic acid (AsA) for human nutrition, but the main pathways involved in its biosynthesis and their regulation are still not fully characterized. To study the transcriptional regulation of AsA accumulation, expression levels of 13 genes involved in AsA biosynthesis, 5 in recycling and 5 in degradation were analyzed in peel and pulp of fruit of two varieties with different AsA concentration: Navel orange (Citrus sinensis) and Satsuma mandarin (Citrus unshiu). AsA accumulation in peel and pulp correlated with the transcriptional profiling of the L-galactose pathway genes, and the myo-inositol pathway appeared to be also relevant in the peel of immature-green orange. Differences in AsA content between varieties were associated with differential gene expression of GDP-mannose pyrophosphorylase (GMP), GDP-L-galactose phosphorylase (GGP) and L-galactose-1-phosphate phosphatase (GPP), myo-inositol oxygenase in peel, and GGP and GPP in pulp. Relative expressions of monodehydroascorbate reductase 3 (MDHAR3) and dehydroascorbate reductase1 (DHAR1) correlated with AsA accumulation during development and ripening in peel and pulp, respectively, and were more highly expressed in the variety with higher AsA contents. Collectively, results indicated a differential regulation of AsA concentration in peel and pulp of citrus fruits that may change during the different stages of fruit development. The L-galactose pathway appears to be predominant in both tissues, but AsA concentration is regulated by complex mechanisms in which degradation and recycling also play important roles.

  13. Do mammals make all their own inositol hexakisphosphate?

    PubMed

    Letcher, Andrew J; Schell, Michael J; Irvine, Robin F

    2008-12-01

    A highly specific and sensitive mass assay for inositol hexakisphosphate (InsP6) was characterized. This centres around phosphorylating InsP6 with [32P]ATP using a recombinant InsP6 kinase from Giardia lambia, followed by HPLC of the 32P-labelled products with an internal [3H]InsP7 standard. This assay was used to quantify InsP6 levels in a variety of biological samples.Concentrations of InsP6 in rat tissues varied from 10-20 microM (assuming 64% of wet weight of tissue is cytosol water), whereas using the same assumption axenic Dictyostelium discoideum cells contained 352 +/- 11 microM InsP6. HeLa cells were seeded at low density and grown to confluence, at which point they contained InsP6 levels per mg of protein similar to rat tissues. This amounted to 1.952 +/- 0.117 nmol InsP6 per culture dish, despite the cells being grown in serum shown to contain no detectable(less than 20 pmol per dish) InsP6. These results demonstrate that mammalian cells synthesize all their own InsP6. Human blood was analysed, and although the white cell fraction contained InsP6 at a concentration comparable with other tissues, in serum and platelet-free plasma no InsP6 was detected (<1 nM InsP6). Human urine was also examined, and also contained no detectable (<5 nM) InsP6. These results suggest that dietary studies purporting to measure InsP6 at micromolar concentrations in human plasma or urine may not have been quantifying this inositol phosphate. Therefore claims that administrating InsP6 in the diet or applying it topically can produce health benefits by increasing extracellular InsP6 levels may require reassessment.

  14. Inositol hexakisphosphate suppresses excitatory neurotransmission via synaptotagmin-1 C2B domain in the hippocampal neuron.

    PubMed

    Yang, Shao-Nian; Shi, Yue; Yang, Guang; Li, Yuxin; Yu, Lina; Shin, Ok-Ho; Bacaj, Taulant; Südhof, Thomas C; Yu, Jia; Berggren, Per-Olof

    2012-07-24

    Inositol hexakisphosphate (InsP(6)) levels rise and fall with neuronal excitation and silence, respectively, in the hippocampus, suggesting potential signaling functions of this inositol polyphosphate in hippocampal neurons. We now demonstrate that intracellular application of InsP(6) caused a concentration-dependent inhibition of autaptic excitatory postsynaptic currents (EPSCs) in cultured hippocampal neurons. The treatment did not alter the size and replenishment rate of the readily releasable pool in autaptic neurons. Intracellular exposure to InsP(6) did not affect spontaneous EPSCs or excitatory amino acid-activated currents in neurons lacking autapses. The InsP(6)-induced inhibition of autaptic EPSCs was effectively abolished by coapplication of an antibody to synaptotagmin-1 C2B domain. Importantly, preabsorption of the antibody with a GST-WT synaptotagmin-1 C2B domain fragment but not with a GST-mutant synaptotagmin-1 C2B domain fragment that poorly reacted with the antibody impaired the activity of the antibody on the InsP(6)-induced inhibition of autaptic EPSCs. Furthermore, K(+) depolarization significantly elevated endogenous levels of InsP(6) and occluded the inhibition of autaptic EPSCs by exogenous InsP(6). These data reveal that InsP(6) suppresses excitatory neurotransmission via inhibition of the presynaptic synaptotagmin-1 C2B domain-mediated fusion via an interaction with the synaptotagmin Ca(2+)-binding sites rather than via interference with presynaptic Ca(2+) levels, synaptic vesicle trafficking, or inactivation of postsynaptic ionotropic glutamate receptors. Therefore, elevated InsP(6) in activated neurons serves as a unique negative feedback signal to control hippocampal excitatory neurotransmission.

  15. Solid state 1D and 2D NMR spectroscopic investigations of conformational changes of metal phytate compounds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytate (myo-inositol-1,2,3,4,5,6-hexakisphosphate) (IP6) is the major organic phosphorus component in ceral grains, legumes and seeds high in oil. The high chelating ability of phytate decreases the nutritional availabilty of dietary metal ions (e.g., Ca2+, Fe3+ and Zn2+). Phytate could also decrea...

  16. Structural diversity of metal phytate compounds: a solid state C-13 NMR and FT-IR spectroscopic investigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytate (myo-inositol-1,2,3,4,5,6-hexakisphosphate) is the major organic phosphorus component in the environment. Phytate contains a 6-carbon ring with 1 hydrogen and 1 phosphate attached to each carbon. Each of the 6 phosphate groups is attached in an ester linkage. Phytate exists in aqueous soluti...

  17. Seeds for a better future: 'low phytate' grains help to overcome malnutrition and reduce pollution.

    PubMed

    Raboy, V

    2001-10-01

    myo-Inositol(1,2,3,4,5,6)hexakisphosphate (InsP(6) or 'phytic acid') was first known as the storage form of phosphorus in seeds. Seed-derived dietary InsP(6) can contribute to iron and zinc deficiency in human populations. Excretion of 'phytic acid phosphorus' by non-ruminants such as poultry, swine and fish can contribute to water pollution. Sustainable solutions to these important problems might depend on progress in the molecular biology and genetics of InsP(6) accumulation during seed development. The development of 'low phytate' grain and legume genotypes could help advance our understanding of this biology, and when used in foods and feeds might help to reduce human malnutrition and reduce animal waste phosphorus.

  18. Screening, selection and characterization of phytic acid degrading lactic acid bacteria from chicken intestine.

    PubMed

    Raghavendra, Ponnala; Halami, Prakash M

    2009-07-31

    This study was undertaken to screen and select potent phytate degrading lactic acid bacteria and to evaluate their additional characteristic features. Forty lactic acid bacterial strains were isolated from different sources and screened for their ability to degrade myo-inositol hexaphosphate or IP(6) by cobalt chloride staining (plate assay) method, using calcium or sodium salt of phytic acid as substrate. All the forty isolates were able to degrade calcium phytate. However, only two Pediococcus pentosaceus strains (CFR R38 and CFR R35) were found to degrade sodium phytate. These strains showed phytase activity of 213 and 89 U at 50 degrees C, respectively and poor acid phosphatase activity. These strains were further evaluated for additional characteristic features. At pH 2, P. pentosaceus strains CFR R38 and CFR R35 showed 50.7 and 48.5 percentage survivability after 2 h of incubation respectively and they could also withstand 0.3% ox-bile. These cultures exhibited 54.6 and 44.8% of hydrophobicity to xylene, antibacterial activity against food borne pathogens and possessed beta-galactosidase activity. The resistance pattern to several antibiotics was also analyzed. The present study indicates that these strains, having phytate degrading ability and other characteristic features can be exploited as starter cultures in fermented foods to improve the mineral bioavailability.

  19. Phytic Acid Metabolism in Lily (Lilium longiflorum Thunb.) Pollen 1

    PubMed Central

    Lin, Jih-Jing; Dickinson, David B.; Ho, Tuan-Hua David

    1987-01-01

    The accumulation of phytic acid during development of lily (Lilium longiflorum Thunb.) pollen and its degradation during germination have been studied. A substantial amount of phytic acid accumulates in lily pollen by 5 days before anthesis, and little change occurs during subsequent maturation. Mature lily pollen contains 7 to 8 micrograms phytic acid per milligram pollen. Considerable degradation of phytic acid occurs by 15 minutes of incubation in glucose culture medium, and very little is left by 3 hours. No partially phosphorylated myo-inositol accumulates during germination. The breakdown of phytic acid proceeds at a constant rate during this time period. The rate is calculated to be 0.037 microgram phytic acid/milligram pollen/minute. Two phytases are detected in germinated lily pollen extract using high performance liquid chromatography with an anion exchange column (diethylaminoethyl-5PW). The results suggest that one of the phytases is already present in mature ungerminated lily pollen and the other one is newly synthesized during germination from a long-lived, pre-existing mRNA. PMID:16665258

  20. ANALYSIS OF RICIN TOXIN PREPARATIONS FOR CARBOHYDRATE AND FATTY ACID ABUNDANCE AND ISOTOPE RATIO INFORMATION

    SciTech Connect

    Wunschel, David S.; Kreuzer-Martin, Helen W.; Antolick, Kathryn C.; Colburn, Heather A.; Moran, James J.; Melville, Angela M.

    2009-12-01

    This report describes method development and preliminary evaluation for analyzing castor samples for signatures of purifying ricin. Ricin purification from the source castor seeds is essentially a problem of protein purification using common biochemical methods. Indications of protein purification will likely manifest themselves as removal of the non-protein fractions of the seed. Two major, non-protein, types of biochemical constituents in the seed are the castor oil and various carbohydrates. The oil comprises roughly half the seed weight while the carbohydrate component comprises roughly half of the remaining “mash” left after oil and hull removal. Different castor oil and carbohydrate components can serve as indicators of specific toxin processing steps. Ricinoleic acid is a relatively unique fatty acid in nature and is the most abundant component of castor oil. The loss of ricinoleic acid indicates a step to remove oil from the seeds. The relative amounts of carbohydrates and carbohydrate-like compounds, including arabinose, xylose, myo-inositol fucose, rhamnose, glucosamine and mannose detected in the sample can also indicate specific processing steps. For instance, the differential loss of arabinose relative to mannose and N-acetyl glucosamine indicates enrichment for the protein fraction of the seed using protein precipitation. The methods developed in this project center on fatty acid and carbohydrate extraction from castor samples followed by derivatization to permit analysis by gas chromatography-mass spectrometry (GC-MS). Method descriptions herein include: the source and preparation of castor materials used for method evaluation, the equipment and description of procedure required for chemical derivatization, and the instrument parameters used in the analysis. Two types of derivatization methods describe analysis of carbohydrates and one procedure for analysis of fatty acids. Two types of GC-MS analysis is included in the method development, one

  1. The effects of phytic acid on the Maillard reaction and the formation of acrylamide.

    PubMed

    Wang, Huan; Zhou, Yamin; Ma, Jimei; Zhou, Yuanyuan; Jiang, Hong

    2013-11-01

    Phytic acid, myo-inositol hexaphosphoric acid, exists in substantial (1-5%) amounts in edible plant seeds. In this study the effects of phytic acid on the Maillard reaction and the formation of acrylamide were investigated. Both phytic acid and phosphate enhanced browning in glucose/β-alanine system, but phytic acid was less effective than phosphate. Higher pH favoured the catalytic activities for both of them. The influence of the types of sugar and amino acid on the reaction was also examined. Browning was suppressed by the addition of calcium and magnesium ions, but an additive effect was observed for ferrous ions and phytic acid in glucose/β-alanine solution at pH 8.0. Both phytic acid and phosphate promoted the polymerisation of the reaction intermediates. The kinetics of Maillard reaction was first-ordered reaction in the presence of phytic acid. Phytic acid was less effective than phosphate in the formation of acrylamide. When potato slices were treated with sodium phytate and calcium chloride successively, the formation of acrylamide was greatly suppressed.

  2. Novel biosensors for quantitative phytic acid and phytase measurement.

    PubMed

    Mak, Wing Cheung; Ng, Yuk Mui; Chan, Chiyui; Kwong, Wai Kuen; Renneberg, Reinhard

    2004-04-15

    Phytase (EC 3.1.3.26) and phytic acid (myo-inositol hexaphosphate) play an important environmental role in poultry industry and have a health aspect in food industry. Novel biosensors have been developed for simple, one step quantitative phytic acid and phytase detection. A system based on the sequentially acting enzyme phytase and pyruvate oxidase (POD) was employed for the development of phytase and phytic acid biosensors. Poly(carbamoylsulphonate) (PCS) hydrogel immobilized POD electrode was applied for the detection of phytase. It was based on the indication of phosphate ions produced by the hydrolysis of phytic acid. The phytase biosensor showed a linear response ranging from 0.5 to 6.0 units/ml. A bi-enzyme sensor based on co-immobilization of phytase and POD was developed for the detection of phytic acid on the basis of amperometric detection of the enzymatically-generated hydrogen peroxide at 0.6 V versus Ag/AgCl. It showed a linear response ranging from 0.2 to 2.0 mM with a detection limit of 0.002 mM.

  3. Metabolic pathways regulated by γ-aminobutyric acid (GABA) contributing to heat tolerance in creeping bentgrass (Agrostis stolonifera)

    PubMed Central

    Li, Zhou; Yu, Jingjin; Peng, Yan; Huang, Bingru

    2016-01-01

    γ-Aminobutyric acid is a non-protein amino acid involved in various metabolic processes. The objectives of this study were to examine whether increased GABA could improve heat tolerance in cool-season creeping bentgrass through physiological analysis, and to determine major metabolic pathways regulated by GABA through metabolic profiling. Plants were pretreated with 0.5 mM GABA or water before exposed to non-stressed condition (21/19 °C) or heat stress (35/30 °C) in controlled growth chambers for 35 d. The growth and physiological analysis demonstrated that exogenous GABA application significantly improved heat tolerance of creeping bentgrass. Metabolic profiling found that exogenous application of GABA led to increases in accumulations of amino acids (glutamic acid, aspartic acid, alanine, threonine, serine, and valine), organic acids (aconitic acid, malic acid, succinic acid, oxalic acid, and threonic acid), sugars (sucrose, fructose, glucose, galactose, and maltose), and sugar alcohols (mannitol and myo-inositol). These findings suggest that GABA-induced heat tolerance in creeping bentgrass could involve the enhancement of photosynthesis and ascorbate-glutathione cycle, the maintenance of osmotic adjustment, and the increase in GABA shunt. The increased GABA shunt could be the supply of intermediates to feed the tricarboxylic acid cycle of respiration metabolism during a long-term heat stress, thereby maintaining metabolic homeostasis. PMID:27455877

  4. Metabolic pathways regulated by γ-aminobutyric acid (GABA) contributing to heat tolerance in creeping bentgrass (Agrostis stolonifera).

    PubMed

    Li, Zhou; Yu, Jingjin; Peng, Yan; Huang, Bingru

    2016-07-26

    γ-Aminobutyric acid is a non-protein amino acid involved in various metabolic processes. The objectives of this study were to examine whether increased GABA could improve heat tolerance in cool-season creeping bentgrass through physiological analysis, and to determine major metabolic pathways regulated by GABA through metabolic profiling. Plants were pretreated with 0.5 mM GABA or water before exposed to non-stressed condition (21/19 °C) or heat stress (35/30 °C) in controlled growth chambers for 35 d. The growth and physiological analysis demonstrated that exogenous GABA application significantly improved heat tolerance of creeping bentgrass. Metabolic profiling found that exogenous application of GABA led to increases in accumulations of amino acids (glutamic acid, aspartic acid, alanine, threonine, serine, and valine), organic acids (aconitic acid, malic acid, succinic acid, oxalic acid, and threonic acid), sugars (sucrose, fructose, glucose, galactose, and maltose), and sugar alcohols (mannitol and myo-inositol). These findings suggest that GABA-induced heat tolerance in creeping bentgrass could involve the enhancement of photosynthesis and ascorbate-glutathione cycle, the maintenance of osmotic adjustment, and the increase in GABA shunt. The increased GABA shunt could be the supply of intermediates to feed the tricarboxylic acid cycle of respiration metabolism during a long-term heat stress, thereby maintaining metabolic homeostasis.

  5. Inositol hexakisphosphate (IP6) generated by IP5K mediates cullin-COP9 signalosome interactions and CRL function

    PubMed Central

    Scherer, Paul C.; Ding, Yan; Liu, Zhiqing; Xu, Jing; Mao, Haibin; Barrow, James C.; Wei, Ning; Zheng, Ning; Snyder, Solomon H.; Rao, Feng

    2016-01-01

    The family of cullin-RING E3 Ligases (CRLs) and the constitutive photomorphogenesis 9 (COP9) signalosome (CSN) form dynamic complexes that mediate ubiquitylation of 20% of the proteome, yet regulation of their assembly/disassembly remains poorly understood. Inositol polyphosphates are highly conserved signaling molecules implicated in diverse cellular processes. We now report that inositol hexakisphosphate (IP6) is a major physiologic determinant of the CRL–CSN interface, which includes a hitherto unidentified electrostatic interaction between the N-terminal acidic tail of CSN subunit 2 (CSN2) and a conserved basic canyon on cullins. IP6, with an EC50 of 20 nM, acts as an intermolecular “glue,” increasing cullin–CSN2 binding affinity by 30-fold, thereby promoting assembly of the inactive CRL–CSN complexes. The IP6 synthase, Ins(1,3,4,5,6)P5 2-kinase (IPPK/IP5K) binds to cullins. Depleting IP5K increases the percentage of neddylated, active Cul1 and Cul4A, and decreases levels of the Cul1/4A substrates p27 and p21. Besides dysregulating CRL-mediated cell proliferation and UV-induced apoptosis, IP5K depletion potentiates by 28-fold the cytotoxic effect of the neddylation inhibitor MLN4924. Thus, IP5K and IP6 are evolutionarily conserved components of the CRL–CSN system and are potential targets for cancer therapy in conjunction with MLN4924. PMID:26976604

  6. Effects of genotype, latitude, and weather conditions on the composition of sugars, sugar alcohols, fruit acids, and ascorbic acid in sea buckthorn (Hippophaë rhamnoides ssp. mongolica) berry juice.

    PubMed

    Zheng, Jie; Yang, Baoru; Trépanier, Martin; Kallio, Heikki

    2012-03-28

    Sea buckthorn berries (Hippophaë rhamnoides ssp. mongolica) of nine varieties were collected from three growth locations in five inconsecutive years (n = 152) to study the compositional differences of sugars, sugar alcohols, fruit acids, and ascorbic acid in berries of different genotypes. Fructose and glucose (major sugars) were highest in Chuiskaya and Vitaminaya among the varieties studied, respectively. Malic acid and quinic acid (major acids) were highest in Pertsik and Vitaminaya, respectively. Ascorbic acid was highest in Oranzhevaya and lowest in Vitaminaya. Berry samples of nine varieties collected from two growth locations in five years (n = 124) were combined to study the effects of latitude and weather conditions on the composition of H. rhamnoides ssp. mongolica. Sea buckthorn berries grown at lower latitude had higher levels of total sugar and sugar/acid ratio and a lower level of total acid and were supposed to have better sensory properties than those grown at higher latitude. Glucose, quinic acid, and ascorbic acid were hardly influenced by weather conditions. The other components showed various correlations with temperature, radiation, precipitation, and humidity variables. In addition, fructose, sucrose, and myo-inositol correlated positively with each other and showed negative correlation with malic acid on the basis of all the samples studied (n = 152).

  7. Acids, sugars, and sugar alcohols in Chinese hawthorn (Crataegus spp.) fruits.

    PubMed

    Liu, Pengzhan; Kallio, Heikki; Lü, Deguo; Zhou, Chuansheng; Ou, Shiyi; Yang, Baoru

    2010-01-27

    Acids, sugars, and sugar alcohols in the fruits of 22 cultivars/origins of three species of hawthorn (Crataegus spp.) were analyzed by gas chromatography and mass spectrometry. Citric acid (2.0-8.4 g/100 g dry mass [DM]), quinic acid (0.5-5.6 g/100 g DM), malic acid (0.3-1.1 g/100 g DM), fructose (5.5-18.4 g/100 g DM), glucose (5.3-16.6 g/100 g DM), sorbitol (3.0-15.7 g/100 g DM), and myo-inositol (0.1-0.3 g/100 g DM) were found in all the samples. Sucrose was present only in C. scabrifolia and three cultivars of C. pinnatifida var. major. C. scabrifolia differed from other species by its high content of quinic acid. The cultivars of C. pinnatifida var. major and C. brettschneideri had a higher content of total sugars and a higher sugar/acid ratio than the natural origins of C. pinnatifida and C. scabrifolia (P < 0.05). The hawthorn samples analyzed fell into two groups rich in sugars and acids respectively. This is the first report of the profiles of sugars and sugar alcohols and the occurrence of quinic acid in hawthorn fruits.

  8. Effects of myo-inositol in women with PCOS: a systematic review of randomized controlled trials.

    PubMed

    Unfer, V; Carlomagno, G; Dante, G; Facchinetti, F

    2012-07-01

    Polycystic ovary syndrome (PCOS) affects 5%-10% of women in reproductive age, and it is the most common cause of infertility due to ovarian dysfunction and menstrual irregularity. Several studies have reported that insulin resistance is common in PCOS women, regardless of the body mass index. The importance of insulin resistance in PCOS is also suggested by the fact that insulin-sensitizing compounds have been proposed as putative treatments to solve the hyperinsulinemia-induced dysfunction of ovarian response to endogenous gonadotropins. Rescuing the ovarian response to endogenous gonadotropins reduces hyperandrogenemia and re-establishes menstrual cyclicity and ovulation, increasing the chance of a spontaneous pregnancy. Among the insulin-sensitizing compounds, there is myo-inosiol (MYO). Previous studies have demonstrated that MYO is capable of restoring spontaneous ovarian activity, and consequently fertility, in most patients with PCOS. With the present review, we aim to provide an overview on the clinical outcomes of the MYO use as a treatment to improve ovarian function and metabolic and hormonal parameters in women with PCOS.

  9. Safety and Pharmacokinetics of Multiple Dose myo-Inositol in Preterm Infants

    PubMed Central

    Phelps, Dale L.; Ward, Robert M.; Williams, Rick L.; Nolen, Tracy L.; Watterberg, Kristi L.; Oh, William; Goedecke, Michael; Ehrenkranz, Richard A.; Fennell, Timothy; Poindexter, Brenda B.; Cotten, C. Michael; Hallman, Mikko; Frantz, Ivan D.; Faix, Roger G.; Zaterka-Baxter, Kristin M.; Das, Abhik; Ball, M. Bethany; Lacy, Conra Backstrom; Walsh, Michele C.; Carlo, Waldemar A.; Sánchez, Pablo J.; Bell, Edward F.; Shankaran, Seetha; Carlton, David P.; Chess, Patricia R.; Higgins, Rosemary D.

    2016-01-01

    BACKGROUND Preterm infants with RDS given inositol had reduced BPD, death and severe ROP. We assessed the safety and pharmacokinetics(PK) of daily inositol to select a dose providing serum levels previously associated with benefit, and to learn if accumulation occurred when administered throughout the normal period of retinal vascularization. METHODS Infants ≤29wks GA (n=122, 14 centers) were randomized and treated with placebo or inositol at 10, 40 or 80mg/kg/day. Intravenous administration converted to enteral when feedings were established, and continued to the first of 10 weeks, 34weeks PMA or discharge. Serum collection employed a sparse sampling population PK design. Inositol urine losses and feeding intakes were measured. Safety was prospectively monitored. RESULTS At 80mg/kg/day mean serum levels reached 140mg/L, similar to Hallman’s findings. Levels declined after 2 weeks, converging in all groups by 6 wks. Analyses showed a mean volume of distribution 0.657 L/kg, clearance 0.058 L/kg/hr, and half-life 7.90 hr. Adverse events and co-morbidities were fewer in the inositol groups, but not significantly so. CONCLUSIONS Multiple dose inositol at 80mg/kg/day was not associated with increased adverse events, achieves previously effective serum levels, and is appropriate for investigation in a Phase 3 trial. PMID:27074126

  10. Transcriptomic Profiling Analysis of Arabidopsis thaliana Treated with Exogenous Myo-Inositol

    PubMed Central

    Ye, Wenxing; Ren, Weibo; Kong, Lingqi; Zhang, Wanjun; Wang, Tao

    2016-01-01

    Myo-insositol (MI) is a crucial substance in the growth and developmental processes in plants. It is commonly added to the culture medium to promote adventitious shoot development. In our previous work, MI was found in influencing Agrobacterium-mediated transformation. In this report, a high-throughput RNA sequencing technique (RNA-Seq) was used to investigate differently expressed genes in one-month-old Arabidopsis seedling grown on MI free or MI supplemented culture medium. The results showed that 21,288 and 21,299 genes were detected with and without MI treatment, respectively. The detected genes included 184 new genes that were not annotated in the Arabidopsis thaliana reference genome. Additionally, 183 differentially expressed genes were identified (DEGs, FDR ≤0.05, log2 FC≥1), including 93 up-regulated genes and 90 down-regulated genes. The DEGs were involved in multiple pathways, such as cell wall biosynthesis, biotic and abiotic stress response, chromosome modification, and substrate transportation. Some significantly differently expressed genes provided us with valuable information for exploring the functions of exogenous MI. RNA-Seq results showed that exogenous MI could alter gene expression and signaling transduction in plant cells. These results provided a systematic understanding of the functions of exogenous MI in detail and provided a foundation for future studies. PMID:27603208

  11. Light avoidance reduces ascorbic acid accumulation in the peel of Citrus fruit.

    PubMed

    Lado, Joanna; Alós, Enriqueta; Rodrigo, María Jesús; Zacarías, Lorenzo

    2015-02-01

    Citrus fruits are highly consumed worldwide and represent one of the most important sources of ascorbic acid (AsA). However, information about the molecular mechanisms regulating AsA accumulation in Citrus fruit and the effects of environmental factors is scarce. In this study we have investigated the effect of fruit shading on AsA content and the expression of AsA biosynthetic, degrading and recycling genes in fruits of different Citrus species. Immature-green fruits were covered at the end of the cell enlargement phase and AsA concentration in the flavedo declined and remained at low levels as compared with light-exposed fruits. Fruit shading marginally altered the expression of genes from the l-galactose pathway and this effect was variable in the four Citrus species. However, specific isoforms (GalUR8 or GalUR12) from the l-galacturonic acid pathway were significantly repressed paralleling the reduction in AsA concentration. No significant effect of shading was detected in transcription of genes of the myo-inositol and l-gulose pathways as well as recycling and degradation. Collectively, results indicate that light avoidance inhibited accumulation of AsA in the flavedo of Citrus fruits and suggest that the l-galacturonic acid pathway has a relevant contribution to AsA content in this tissue.

  12. Inositol hexakisphosphate kinase-1 regulates behavioral responses via GSK3 signaling pathways.

    PubMed

    Chakraborty, A; Latapy, C; Xu, J; Snyder, S H; Beaulieu, J-M

    2014-03-01

    Glycogen synthase kinase 3 (GSK3), a prominent enzyme in carbohydrate metabolism, also has a major role in brain function. It is physiologically regulated by the kinase Akt, which phosphorylates GSK3 to inhibit catalytic activity. Inositol hexakisphosphate-1 (IP6K1) generates the inositol pyrophosphate diphosphoinositol pentakisphosphate (IP7), which physiologically inhibits Akt leading to enhanced GSK3 activity. We report that IP6K1 binds and stimulates GSK3 enzymatic activity in a non-catalytic fashion. Physiological relevance is evident in the inhibition of GSK3 activity in the brains of IP6K1-deleted mice. Behavioral alterations of IP6K1 knockout mice resemble those of GSK3 mutants. Accordingly, modulation of IP6K1-GSK3β interaction may exert beneficial effects in psychiatric disorders involving GSK3.

  13. Effect of inositol and phytases on hematological indices and α-1 acid glycoprotein levels in laying hens fed phosphorus-deficient corn-soybean meal-based diets.

    PubMed

    Zyła, K; Grabacka, M; Pierzchalska, M; Duliński, R; Starzyńska-Janiszewska, A

    2013-01-01

    The effects of feeding low nonphytate phosphorus (NPP) corn-soybean meal-based diets supplemented with myo-inositol at 0.1%, or with phytase B at 1,300 acid phosphatase units/kg, or with phytase B enriched in 6-phytase A at 300 phytase units/kg on the hematological indices and the α-1 acid glycoprotein (AGP) concentrations in the blood of Bovans Brown laying hens were investigated. The experimental design comprised also a negative control diet and an internal control diet that had the NPP content adjusted by the addition of 0.304 g of monocalcium phosphate per kg to reach the NPP level similar to that resulting from the combined action of both phytases. A total of sixty 50-wk-old hens were randomly assigned to the dietary treatments with 12 cage replicates of 1 hen, and fed the experimental diets until wk 62, when the blood samples were taken and analyzed for basic hematological indices and for AGP concentrations in sera. The hematological indices from all the experimental groups remained in a normal range; nevertheless, the statistically significant effects of diet on hemoglobin concentration (P = 0.003), erythrocyte counts (P = 0.035), the percentage of lymphocytes (P = 0.020), heterophils (P = 0.002), eosinophils (P = 0.023), and basophils (P = 0.001) in the leucocyte population, as well as on the heterophil to lymphocyte ratio (P = 0.003), were observed. The highest erythrocyte counts were characteristic for hens fed the diet supplemented with both phytase A and phytase B. The highest heterophil to lymphocyte ratios were found in blood of hens fed the diet supplemented with phytase B, whereas the highest basophil percentages and the highest AGP concentrations occurred in birds fed the negative control diet. A highly significant correlation was observed between AGP concentrations in sera and BW losses determined previously. The results indicate that the low-NPP corn soybean meal-based diets increased acute phase protein level in laying hens. Phytase B alone

  14. Alkaline phytase from lily pollen: Investigation of biochemical properties.

    PubMed

    Jog, Sonali P; Garchow, Barry G; Mehta, Bakul Dhagat; Murthy, Pushpalatha P N

    2005-08-15

    Phytases catalyze the hydrolysis of phytic acid (InsP6, myo-inositol hexakisphosphate), the most abundant inositol phosphate in cells. In cereal grains and legumes, it constitutes 3-5% of the dry weight of seeds. The inability of humans and monogastric animals such as swine and poultry to absorb complexed InsP6 has led to nutritional and environmental problems. The efficacy of supplemental phytases to address these issues is well established; thus, there is a need for phytases with a range of biochemical and biophysical properties for numerous applications. An alkaline phytase that shows unique catalytic properties was isolated from plant tissues. In this paper, we report on the biochemical properties of an alkaline phytase from pollen grains of Lilium longiflorum. The enzyme exhibits narrow substrate specificity, it hydrolyzed InsP6 and para-nitrophenyl phosphate (pNPP). Alkaline phytase followed Michaelis-Menten kinetics with a K(m) of 81 microM and V(max) of 217 nmol Pi/min/mg with InsP6 and a K(m) of 372 microM and V(max) of 1272 nmol Pi/min/mg with pNPP. The pH optimum was 8.0 with InsP6 as the substrate and 7.0 with pNPP. Alkaline phytase was activated by calcium and inactivated by ethylenediaminetetraacetic acid; however, the enzyme retained a low level of activity even in Ca2+-free medium. Fluoride as well as myo-inositol hexasulfate did not have any inhibitory affect, whereas vanadate inhibited the enzyme. The enzyme was activated by sodium chloride and potassium chloride and inactivated by magnesium chloride; the activation by salts followed the Hofmeister series. The temperature optimum for hydrolysis is 55 degrees C; the enzyme was stable at 55 degrees C for about 30 min. The enzyme has unique properties that suggest the potential to be useful as a feed supplement.

  15. Metabolomic shifts in Brassica napus lines with enhanced BnPLC2 expression impact their response to low temperature stress and plant pathogens

    PubMed Central

    Nokhrina, Kateryna; Ray, Heather; Bock, Cheryl; Georges, Fawzy

    2014-01-01

    Phosphatidylinositol-specific phospholipase C2 (PLC2) is a signaling enzyme with hydrolytic activity against membrane-bound phosphoinositides. It catalyzes the cleavage of phosphatidylinositol(4,5)bisphosphate (PtdIns(4,5)P2) into two initial second messengers, myo-inositol-1,4,5-trisphosphate (InsP3) and diacylglycerol (DAG). The former, as well as its fully phosphorylated derivative, myo-inositol-1,2,3,4,5,6-hexakisphosphate (InsP6), play a major role in calcium signaling events within the cell, while DAG may be used in the regeneration of phospholipids or as a precursor for phosphatidic acid (PA) biosynthesis, an important signaling molecule involved in both biotic and abiotic types of stress tolerance. Overexpression of the gene for Brassica napus phospholipase C2 (BnPLC2) in Brassica napus has been shown to enhance drought tolerance, modulate multiple genes involved in different processes and favorably affect hormonal levels in different tissues. We, therefore, undertook the current study with a view to examining, at the metabolome level, its effect on both abiotic (low temperature) and biotic (stem white rot disease) types of stress in canola. Thus, while transgenic plants exhibited a significant rise in maltose levels and a concomitant elevation in some unsaturated free fatty acids (FFAs), glycerol, and glycerol 3-phosphate under subzero temperatures, they accumulated high levels of raffinose, stachyose and other sugars as well as some flavonoids under acclimatization conditions. Collectively, overexpression of BnPLC2 appears to have triggered different metabolite patterns consistent with its abiotic and, to a limited extent, biotic stress tolerance phenotypes. PMID:24787279

  16. Transcriptomic Analysis Reveals the Metabolic Mechanism of L-Ascorbic Acid in Ziziphus jujuba Mill.

    PubMed Central

    Zhang, Chunmei; Huang, Jian; Li, Xingang

    2016-01-01

    Chinese jujube (Ziziphus jujuba Mill.) is the most economically important member of the Rhamnaceae family and contains a high concentration of ascorbic acid (AsA). To explore the metabolic mechanism of AsA accumulation, we investigated the abundance of AsA in the fruit development stages, the leaf and flower of Z. jujuba cv Junzao, and the mature fruit of one type of wild jujube (Z. jujuba var. spinosa Hu, Yanchuan sour jujube). And the expression patterns of genes involved in AsA biosynthesis, degradation, and recycling were analyzed. The result showed that AsA biosynthesis during early fruit development (the enlargement stage) is the main reason for jujube high accumulation. The L-galactose pathway plays a predominant role in the biosynthesis of AsA during jujube fruit development, and the genes GMP1, GME1, GGP, and GaLDH involved in the determination of AsA concentration during fruit development and in different genotypes; the myo-inositol pathway along with the genes GME2 and GMP2 in the L-galactose pathway play a compensatory role in maintaining AsA accumulation during the ripening stage. These findings enhance our understanding of the molecular mechanism in regulating AsA accumulation for jujube. PMID:26913041

  17. Carbohydrate, Organic Acid, and Amino Acid Composition of Bacteroids and Cytosol from Soybean Nodules 1

    PubMed Central

    Streeter, John G.

    1987-01-01

    Metabolites in Bradyrhizobium japonicum bacteroids and in Glycine max (L.) Merr. cytosol from root nodules were analyzed using an isolation technique which makes it possible to estimate and correct for changes in concentration which may occur during bacteroid isolation. Bacteroid and cytosol extracts were fractionated on ion-exchange columns and were analyzed for carbohydrate composition using gas-liquid chromatography and for organic acid and amino acid composition using high performance liquid chromatography. Analysis of organic acids in plant tissues as the phenacyl derivatives is reported for the first time and this approach revealed the presence of several unknown organic acids in nodules. The time required for separation of bacteroids and cytosol was varied, and significant change in concentration of individual compounds during the separation of the two fractions was estimated by calculating the regression of concentration on time. When a statistically significant slope was found, the true concentration was estimated by extrapolating the regression line to time zero. Of 78 concentration estimates made, there was a statistically significant (5% level) change in concentration during sample preparation for only five metabolites: glucose, sucrose, and succinate in the cytosol and d-pinitol and serine in bacteroids. On a mass basis, the major compounds in bacteroids were (descending order of concentration): myo-inositol, d-chiro-inositol, α,α-trehalose, sucrose, aspartate, glutamate, d-pinitol, arginine, malonate, and glucose. On a proportional basis (concentration in bacteroid as percent of concentration in bacteroid + cytosol fractions), the major compounds were: α-aminoadipate (94), trehalose (66), lysine (58), and arginine (46). The results indicate that metabolite concentrations in bacteroids can be reliably determined. PMID:16665774

  18. Enhanced proton conductivity of Nafion hybrid membrane under different humidities by incorporating metal-organic frameworks with high phytic acid loading.

    PubMed

    Li, Zhen; He, Guangwei; Zhang, Bei; Cao, Ying; Wu, Hong; Jiang, Zhongyi; Tiantian, Zhou

    2014-06-25

    In this study, phytic acid (myo-inositol hexaphosphonic acid) was first immobilized by MIL101 via vacuum-assisted impregnation method. The obtained phytic@MIL101 was then utilized as a novel filler to incorporate into Nafion to fabricate hybrid proton exchange membrane for application in PEMFC under different relative humidities (RHs), especially under low RHs. High loading and uniform dispersion of phytic acid in MIL 101(Cr) were achieved as demonstrated by ICP, FT-IR, XPS, and EDS-mapping. The phytic@MIL101 was dispersed homogeneously in the Nafion matrix when the filler content was less than 12%. Hybrid membranes were evaluated by proton conductivity, mechanical property, thermal stability, and so forth. Remarkably, the Nafion/phytic@MIL hybrid membranes showed high proton conductivity at different RHs, especially under low RHs, which was up to 0.0608 S cm(-1) and 7.63 × 10(-4) S cm(-1) at 57.4% RH and 10.5% RH (2.8 and 11.0 times higher than that of pristine membrane), respectively. Moreover, the mechanical property of Nafion/phtic@MIL hybrid membranes was substantially enhanced and the thermal stability of membranes was well preserved.

  19. Kinetic and equilibrium constants of phytic acid and ferric and ferrous phytate derived from nuclear magnetic resonance spectroscopy.

    PubMed

    Heighton, Lynne; Schmidt, Walter F; Siefert, Ronald L

    2008-10-22

    Inositol phosphates are metabolically derived organic phosphates (P) that increasingly appear to be an important sink and source of P in the environment. Salts of myo-inositol hexakisdihydrogen phosphate (IHP) or more commonly phytate are the most common inositol phosphates in the environment. IHP resists acidic dephosphorylation and enzymatic dephosphorylation as ferric or ferrous IHP. Mobility of IHP iron complexes is potentially pH and redox responsive, making the time scale and environmental fate and transport of the P associated with the IHP of interest to the mass balance of phosphorus. Ferric and ferrous complexes of IHP were investigated by proton nuclear magnetic resonance spectroscopy ( (1)H NMR) and enzymatic dephosphorylation. Ferrous IHP was found to form quickly and persist for a longer period then ferric IHP. Dissociation constants derived from (1)H NMR experiments of chemically exchanging systems at equilibrium were 1.11 and 1.19 and formation constants were 0.90 and 0.84 for ferric and ferrous IHP, respectively. The recovery of P from enzymatic dephosphorylation of ferric and ferrous IHP was consistent with the magnitude of the kinetic and equilibrium rate constants.

  20. INOSITOL HEXAKISPHOSPHATE MEDIATES APOPTOSIS IN HUMAN BREAST ADENOCARCINOMA MCF-7 CELL LINE VIA INTRINSIC PATHWAY

    SciTech Connect

    Agarwal, Rakhee; Ali, Nawab

    2010-04-12

    Inositol polyphosphates (InsP{sub s}) are naturally occurring compounds ubiquitously present in plants and animals. Inositol hexakisphosphate (InsP{sub 6}) is the most abundant among all InsP{sub s} and constitutes the major portion of dietary fiber in most cereals, legumes and nuts. Certain derivatives of InsP{sub s} also regulate cellular signaling mechanisms. InsP{sub s} have also been shown to reduce tumor formation and induce apoptosis in cancerous cells. Therefore, in this study, the effects of InsPs on apoptosis were studied in an attempt to investigate their potential anti-cancer therapeutic application and understand their mechanism of action. Acridine orange and ethidium bromide staining suggested that InsP{sub 6} dose dependently induced apoptosis in human breast adenocarcinoma MCF-7 cells. Among InsP{sub s} tested (InsP{sub 3}, InsP{sub 4}, InsP{sub 5}, and InsP{sub 6}), InsP{sub 6} was found to be the most effective in inducing apoptosis. Furthermore, effects of InsP{sub 6} were found most potent inducing apoptosis. Etoposide, the drug known to induce apoptosis in both in vivo and in vitro, was used as a positive control. Western blotting experiments using specific antibodies against known apoptotic markers suggested that InsP{sub 6} induced apoptotic changes were mediated via an intrinsic apoptotic pathway.

  1. Inositol Hexakisphosphate Mediates Apoptosis in Human Breast Adenocarcinoma MCF-7 Cell Line via Intrinsic Pathway

    NASA Astrophysics Data System (ADS)

    Agarwal, Rakhee; Ali, Nawab

    2010-04-01

    Inositol polyphosphates (InsPs) are naturally occurring compounds ubiquitously present in plants and animals. Inositol hexakisphosphate (InsP6) is the most abundant among all InsPs and constitutes the major portion of dietary fiber in most cereals, legumes and nuts. Certain derivatives of InsPs also regulate cellular signaling mechanisms. InsPs have also been shown to reduce tumor formation and induce apoptosis in cancerous cells. Therefore, in this study, the effects of InsPs on apoptosis were studied in an attempt to investigate their potential anti-cancer therapeutic application and understand their mechanism of action. Acridine orange and ethidium bromide staining suggested that InsP6 dose dependently induced apoptosis in human breast adenocarcinoma MCF-7 cells. Among InsPs tested (InsP3, InsP4, InsP5, and InsP6), InsP6 was found to be the most effective in inducing apoptosis. Furthermore, effects of InsP6 were found most potent inducing apoptosis. Etoposide, the drug known to induce apoptosis in both in vivo and in vitro, was used as a positive control. Western blotting experiments using specific antibodies against known apoptotic markers suggested that InsP6 induced apoptotic changes were mediated via an intrinsic apoptotic pathway.

  2. Autoinhibition of Bruton's tyrosine kinase (Btk) and activation by soluble inositol hexakisphosphate

    PubMed Central

    Wang, Qi; Vogan, Erik M; Nocka, Laura M; Rosen, Connor E; Zorn, Julie A; Harrison, Stephen C; Kuriyan, John

    2015-01-01

    Bruton's tyrosine kinase (Btk), a Tec-family tyrosine kinase, is essential for B-cell function. We present crystallographic and biochemical analyses of Btk, which together reveal molecular details of its autoinhibition and activation. Autoinhibited Btk adopts a compact conformation like that of inactive c-Src and c-Abl. A lipid-binding PH-TH module, unique to Tec kinases, acts in conjunction with the SH2 and SH3 domains to stabilize the inactive conformation. In addition to the expected activation of Btk by membranes containing phosphatidylinositol triphosphate (PIP3), we found that inositol hexakisphosphate (IP6), a soluble signaling molecule found in both animal and plant cells, also activates Btk. This activation is a consequence of a transient PH-TH dimerization induced by IP6, which promotes transphosphorylation of the kinase domains. Sequence comparisons with other Tec-family kinases suggest that activation by IP6 is unique to Btk. DOI: http://dx.doi.org/10.7554/eLife.06074.001 PMID:25699547

  3. Synthesis of inositol phosphate ligands of plant hormone-receptor complexes: pathways of inositol hexakisphosphate turnover.

    PubMed

    Hanke, David E; Parmar, Paroo N; Caddick, Samuel E K; Green, Porntip; Brearley, Charles A

    2012-06-15

    Reduction of phytate is a major goal of plant breeding programs to improve the nutritional quality of crops. Remarkably, except for the storage organs of crops such as barley, maize and soybean, we know little of the stereoisomeric composition of inositol phosphates in plant tissues. To investigate the metabolic origins of higher inositol phosphates in photosynthetic tissues, we have radiolabelled leaf tissue of Solanum tuberosum with myo-[2-3H]inositol, undertaken a detailed analysis of inositol phosphate stereoisomerism and permeabilized mesophyll protoplasts in media containing inositol phosphates. We describe the inositol phosphate composition of leaf tissue and identify pathways of inositol phosphate metabolism that we reveal to be common to other kingdoms. Our results identify the metabolic origins of a number of higher inositol phosphates including ones that are precursors of cofactors, or cofactors of plant hormone-receptor complexes. The present study affords alternative explanations of the effects of disruption of inositol phosphate metabolism reported in other species, and identifies different inositol phosphates from that described in photosynthetic tissue of the monocot Spirodela polyrhiza. We define the pathways of inositol hexakisphosphate turnover and shed light on the occurrence of a number of inositol phosphates identified in animals, for which metabolic origins have not been defined.

  4. Molecular characterization, physicochemical properties, known and potential applications of phytases: An overview.

    PubMed

    Rao, D E C S; Rao, K V; Reddy, T P; Reddy, V D

    2009-01-01

    Phytases (myo-inositol hexakisphosphate phosphohydrolases) hydrolyze the phosphate ester bonds of phytate-releasing phosphate and lower myo-inositol phosphates and/or myo-inositol. Phytases, in general, are known to enhance phosphate and mineral uptake in monogastric animals such as poultry, swine, and fish, which cannot metabolize phytate besides reducing environmental pollution significantly. In this study, the molecular, biophysical, and biochemical properties of phytases are reviewed in detail. Alterations in the molecular and catalytic properties of phytases, upon expression in heterologous hosts, are discussed. Diverse applications of phytases as feed additives, as soil amendment, in aquaculture, development of transgenic organisms, and as nutraceuticals in the human diet also are dealt with. Furthermore, phytases are envisaged to serve as potential enzymes that can produce versatile lower myo-inositol phosphates of pharmaceutical importance. Development of phytases with improved attributes is an important area being explored through genetic and protein engineering approaches, as no known phytase can fulfill all the properties of an ideal feed additive.

  5. Phytic acid suppresses ischemia-induced hydroxyl radical generation in rat myocardium.

    PubMed

    Obata, Toshio; Nakashima, Michiko

    2016-03-05

    The present study examined whether ischemia-reperfusion-induced hydroxyl radical (·OH) generation was attenuated by myo-inositol hexaphosphoric acid (phytic acid). A flexibly mounted microdialysis technique was used to detect the generation of ·OH in in vivo rat hearts. To measure the level of ·OH, sodium salicylate in Ringer's solution (0.5mM or 0.5 nmol/μl/min) was infused directly through a microdialysis probe to detect the generation of ·OH as reflected by the nonenzymatic formation of 2,3-dihydroxybenzoic acid (2,3-DHBA). To confirm the generation of ·OH by Fenton-type reaction, iron(II) was infused through a microdialysis probe. A positive linear correlation between iron(II) and the formation of 2,3-DHBA (R(2)=0.983) was observed. However, the level of 2,3-DHBA in norepinephrine (100 μM) plus phytic acid (100 μM) treated group were significantly lower than those observed in norepinephrine-only-treated group (n=6, *p<0.05). To examine the effect of phytic acid on ischemia-reperfusion-induced ·OH generation, the heart was subjected to myocardial ischemia for 15 min by occlusion of the left anterior descending coronary artery (LAD). When the heart was reperfused, the normal elevation of 2,3-DHBA in the heart dialysate was not observed in animals pretreated with phytic acid. These results suggest that phytic acid is associated with antioxidant effect due to the suppression of iron-induced ·OH generation.

  6. The pathway for the production of inositol hexakisphosphate in human cells.

    PubMed

    Verbsky, John W; Chang, Shao-Chun; Wilson, Monita P; Mochizuki, Yasuhiro; Majerus, Philip W

    2005-01-21

    The yeast and Drosophila pathways leading to the production of inositol hexakisphosphate (InsP(6)) have been elucidated recently. The in vivo pathway in humans has been assumed to be similar. Here we show that overexpression of Ins(1,3,4)P(3) 5/6-kinase in human cell lines results in an increase of inositol tetrakisphosphate (InsP(4)) isomers, inositol pentakisphosphate (InsP(5)) and InsP(6), whereas its depletion by RNA interference decreases the amounts of these inositol phosphates. Expression of Ins(1,3,4,6)P(4) 5-kinase does not increase the amount of InsP(5) and InsP(6), although its depletion does block InsP(5) and InsP(6) production, showing that it is necessary for production of InsP(5) and InsP(6). Expression of Ins(1,3,4,5,6)P(5) 2-kinase increases the amount of InsP(6) by depleting the InsP(5) in the cell, and depletion of 2-kinase decreases the amount of InsP(6) and causes an increase in InsP(5). These results are consistent with a pathway that produces InsP(6) through the sequential action of Ins(1,3,4)P(3) 5/6-kinase, Ins(1,3,4,6)P(4) 5-kinase, and Ins(1,3,4,5,6)P5 2-kinase to convert Ins(1,3,4)P(3) to InsP(6). Furthermore, the evidence implicates 5/6-kinase as the rate-limiting enzyme in this pathway.

  7. Cytoplasmic inositol hexakisphosphate production is sufficient for mediating the Gle1-mRNA export pathway.

    PubMed

    Miller, Aimee L; Suntharalingam, Mythili; Johnson, Sylvia L; Audhya, Anjon; Emr, Scott D; Wente, Susan R

    2004-12-03

    Production of inositol hexakisphosphate (IP6) by Ipk1, the inositol-1,3,4,5,6-pentakisphosphate 2-kinase, is required for Gle1-mediated mRNA export in Saccharomyces cerevisiae cells. To examine the network of interactions that require IP6 production, an analysis of fitness defects was conducted in mutants harboring both an ipk1 null allele and a mutant allele in genes encoding nucleoporins or transport factors. Enhanced lethality was observed with a specific subset of mutants, including nup42, nup116, nup159, dbp5, and gle2, all of which had been previously connected to Gle1 function. Complementation of the nup116Deltaipk1Delta and nup42Deltaipk1Delta double mutants did not require the Phe-Gly repeat domains in the respective nucleoporins, suggesting that IP6 was acting subsequent to heterogeneous nuclear ribonucleoprotein targeting to the nuclear pore complex. With Nup42 and Nup159 localized exclusively to the nuclear pore complex cytoplasmic side, we speculated that IP6 may regulate a cytoplasmic step in mRNA export. To test this prediction, the spatial requirements for the production of IP6 were investigated. Restriction of Ipk1 to the cytoplasm did not block IP6 production. Moreover, coincident sequestering of both Ipk1 and Mss4 (an enzyme required for phosphatidylinositol 4,5-bisphosphate production) to the cytoplasm also did not block IP6 production. Given that the kinase required for inositol 1,3,4,5,6-pentakisphosphate production (Ipk2) is localized in the nucleus, these results indicated that soluble inositides were diffusing between the nucleus and the cytoplasm. Additionally, the cytoplasmic production of IP6 by plasma membrane-anchored Ipk1 rescued a gle1-2 ipk1-4 synthetic lethal mutant. Thus, cytoplasmic IP6 production is sufficient for mediating the Gle1-mRNA export pathway.

  8. Malignant H1299 tumour cells preferentially internalize iron-bound inositol hexakisphosphate.

    PubMed

    Helmis, Christina; Blechner, Christine; Lin, Hongying; Schweizer, Michaela; Mayr, Georg W; Nielsen, Peter; Windhorst, Sabine

    2013-10-22

    In colon enterocytes and in well-differentiated colon cancer CaCo-2 cells, InsP6 (inositol hexakisphosphate) inhibits iron uptake by forming extracellular insoluble iron/InsP6 complexes. In this study, we confirmed that CaCo-2 cells are not able to take up iron/InsP6 but, interestingly, found that the cells are able to internalize metal-free and Cr3+-bound InsP6. Thus, the inability of CaCo-2 cells to take up iron/InsP6 complexes seems to be due to the iron-bound state of InsP6. Since recently we demonstrated that the highly malignant bronchial carcinoma H1299 cells internalize and process InsP6, we examined whether these cells may be able to take up iron/InsP6 complexes. Indeed, we found that InsP6 dose-dependently increased uptake of iron and demonstrated that in the iron-bound state InsP6 is more effectively internalized than in the metal-free or Cr3+-bound state, indicating that H1299 cells preferentially take up iron/InsP6 complexes. Electron microscope and cell fraction assays indicate that after uptake H1299 cells mainly stored InsP6/iron in lysosomes as large aggregates, of which about 10% have been released to the cytosol. However, this InsP6-mediated iron transport had no significant effects on cell viability. This result together with our finding that the well-differentiated CaCo-2 cells did not, but the malignant H1299 cells preferentially took up iron/InsP6, may offer the possibility to selectively transport cytotoxic substances into tumour cells.

  9. Quantifying Bioactive P Pools in Fertilized and Manure-Amended Soils by Purified Phytic-Acid High Affinity Aspergillus phosphohydrolases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In areas of intensive animal agriculture, repeated land application of manure resulted in elevated soil concentrations of inorganic and organic phosphorus (P) myo-Inositol hexaphosphate, lower phosphomonoesters are the most abundant organic P compounds. Such P-enriched soils are potential pollution...

  10. Regulation of L-ascorbic acid content in strawberry fruits

    PubMed Central

    Cruz-Rus, Eduardo; Amaya, Iraida; Sánchez-Sevilla, José F.; Botella, Miguel A.; Valpuesta, Victoriano

    2011-01-01

    Plants have several L-ascorbic acid (AsA) biosynthetic pathways, but the contribution of each one to the synthesis of AsA varyies between different species, organs, and developmental stages. Strawberry (Fragaria×ananassa) fruits are rich in AsA. The pathway that uses D-galacturonate as the initial substrate is functional in ripe fruits, but the contribution of other pathways to AsA biosynthesis has not been studied. The transcription of genes encoding biosynthetic enzymes such as D-galacturonate reductase (FaGalUR) and myo-inositol oxygenase (FaMIOX), and the AsA recycling enzyme monodehydroascorbate reductase (FaMDHAR) were positively correlated with the increase in AsA during fruit ripening. Fruit storage for 72 h in a cold room reduced the AsA content by 30%. Under an ozone atmosphere, this reduction was 15%. Ozone treatment increased the expression of the FaGalUR, FaMIOX, and L-galactose-1-phosphate phosphatase (FaGIPP) genes, and transcription of the L-galactono-1,4-lactone dehydrogenase (FaGLDH) and FAMDHAR genes was higher in the ozone-stored than in the air-stored fruits. Analysis of AsA content in a segregating population from two strawberry cultivars showed high variability, which did not correlate with the transcription of any of the genes studied. Study of GalUR protein in diverse cultivars of strawberry and different Fragaria species showed that a correlation between GalUR and AsA content was apparent in most cases, but it was not general. Three alleles were identified in strawberry, but any sequence effect on the AsA variability was eliminated by analysis of the allele-specific expression. Taken together, these results indicate that FaGalUR shares the control of AsA levels with other enzymes and regulatory elements in strawberry fruit. PMID:21561953

  11. The incorporation of myo-inositol into phosphatidylinositol derivatives is stimulated during hormone-induced meiotic maturation of amphibian oocytes

    SciTech Connect

    Carrasco, D.; Allende, C.C.; Allende, J.E. )

    1990-12-01

    The incorporation of myo-({sup 3}H)inositol into phosphatidylinositol and its phosphorylated derivatives was studied by microinjection of the radioactive precursor into Xenopus laevis oocytes. Induction of meiotic maturation of the oocytes by treatment with either progesterone one or insulin resulted in a significant increase in the incorporation of myo-({sup 3}H)inositol into the phospholipid fraction. This increase occurred 3-6 h after hormonal treatment, a time coincident with the start of the breakdown of the nuclear envelope, and requires protein synthesis. The effect of progesterone and insulin contrasts with the effect of acetylcholine, which acts through a muscarinic receptor causing the activation of phospholipase C, since the latter effector causes an increase in myo-({sup 3}H)inositol incorporation, which is more rapid and does not require protein synthesis. These results suggest that the meiotic maturation process is connected with changes in inositol metabolism in the amphibian oocyte.

  12. Phytate degrading activities of lactic acid bacteria isolated from traditional fermented food

    NASA Astrophysics Data System (ADS)

    Damayanti, Ema; Ratisiwi, Febiyani Ndaru; Istiqomah, Lusty; Sembiring, Langkah; Febrisiantosa, Andi

    2017-03-01

    The objective of this study was to determine the potential of LAB with phytate degrading activity from fermented traditional food grain-based and legume-based. Lactic acid bacteria were isolated from different sources of traditional fermented food from Gunungkidul Yogyakarta Indonesia such as gembus tempeh (tofu waste), soybean tempeh, lamtoro tempeh (Leucaena bean) and kara tempeh. Isolation of LAB was performed using Total Plate Count (TPC) on de Man Rogosa Sharpe Agar (MRSA) medium supplemented with CaCO3. They were screened for their ability to degrade myo-inositol hexaphosphate or IP6 by using qualitative streak platemethod with modified de Man Rogosa-MorpholinoPropanesulfonic Acid Sharpe (MRS-MOPS) medium contained sodium salt of phytic acid as substrate and cobalt chloride staining (plate assay) method. The selected isolates were further assayed for phytase activities using quantitative method with spectrophotometer and the two selected isolates growth were optimized. Furthermore, thhe isolates that shown the highest phytase activity was characterized and identified using API 50 CH kitand 16S rRNA gene sequencing. The results showed that there were 18 LAB isolates obtained from samplesand 13 isolates were able to degrade sodium phytate based on qualitative screening. According to quantitative assay, the highest phytate degrading activities were found in TG-2(23.562 U/mL) and TG-1 (19.641 U/mL) isolated from gembus tempeh. The phytate activity of TG-2 was optimum at 37 °C with agitation, while the phytate activity of TG-1 was optimum at 45 °C without agitation. Characterization and identification of TG-2 isolate with the highest phytate degrading activity using API 50 CH and 16S rRNA showed that TG-2had homology with Lactobacillus fermentum. It could be concluded that LAB from from fermented traditional food grain-based and legume-based produced the extracellular phytase. Keywords: lactic acid bacteria, tempeh, phytatedegrading activity

  13. Inositol Hexakisphosphate Kinase-3 Regulates the Morphology and Synapse Formation of Cerebellar Purkinje Cells via Spectrin/Adducin

    PubMed Central

    Fu, Chenglai; Xu, Jing; Li, Ruo-Jing; Crawford, Joshua A.; Khan, A. Basit; Ma, Ting Martin; Cha, Jiyoung Y.; Snowman, Adele M.; Pletnikov, Mikhail V.

    2015-01-01

    The inositol hexakisphosphate kinases (IP6Ks) are the principal enzymes that generate inositol pyrophosphates. There are three IP6Ks (IP6K1, 2, and 3). Functions of IP6K1 and IP6K2 have been substantially delineated, but little is known of IP6K3's role in normal physiology, especially in the brain. To elucidate functions of IP6K3, we generated mice with targeted deletion of IP6K3. We demonstrate that IP6K3 is highly concentrated in the brain in cerebellar Purkinje cells. IP6K3 physiologically binds to the cytoskeletal proteins adducin and spectrin, whose mutual interactions are perturbed in IP6K3-null mutants. Consequently, IP6K3 knock-out cerebella manifest abnormalities in Purkinje cell structure and synapse number, and the mutant mice display deficits in motor learning and coordination. Thus, IP6K3 is a major determinant of cytoskeletal disposition and function of cerebellar Purkinje cells. SIGNIFICANCE STATEMENT We identified and cloned a family of three inositol hexakisphosphate kinases (IP6Ks) that generate the inositol pyrophosphates, most notably 5-diphosphoinositol pentakisphosphate (IP7). Of these, IP6K3 has been least characterized. In the present study we generated IP6K3 knock-out mice and show that IP6K3 is highly expressed in cerebellar Purkinje cells. IP6K3-deleted mice display defects of motor learning and coordination. IP6K3-null mice manifest aberrations of Purkinje cells with a diminished number of synapses. IP6K3 interacts with the cytoskeletal proteins spectrin and adducin whose altered disposition in IP6K3 knock-out mice may mediate phenotypic features of the mutant mice. These findings afford molecular/cytoskeletal mechanisms by which the inositol polyphosphate system impacts brain function. PMID:26245967

  14. Evaluation of beneficial attributes for phytate-degrading Pediococcus pentosaceus CFR R123.

    PubMed

    Raghavendra, P; Rao, T S C; Halami, P M

    2010-09-01

    In this study we have screened and selected potent phytate-degrading lactic acid bacteria (LAB), and evaluated their beneficial attributes. Around 60 LAB strains were isolated from several cereal- and pulse-based conventional fermented preparations. They were screened for their ability to degrade myo-inositol hexakisphosphate (IP6) by cobalt chloride qualitative staining method (plate assay). One of the cultures, Pediococcus pentosaceus CFR R123, was capable of degrading both calcium and sodium salts of phytic acid. Additionally, we have carried out an in vitro evaluation for the beneficial attributes of phytate degrading CFR R123. P. pentosaceus CFR R123 showed 53% survivability at pH 2 and 62% at pH 2.5, whereas cultures of Lactobacillus rhamnosus GG showed a survivability of 55% and 82%, respectively. CFR R123 could also withstand 0.3% ox-bile, whereas no growth was observed for GG. The strain CFR R123 exhibited 62.8% hydrophobicity to xylene whereas 59% was found for GG. Both the tested strains showed a good spectrum of antibacterial activity against food-borne pathogens like Escherichia coli, Listeria monocytogenes Scott A, etc. P. pentosaceus CFR R123 possessed β-galactosidase activity and cholesterol reduction ability. In conclusion, LAB with phytate degrading ability and several beneficial attributes could potentially be used as a starter culture to improve the nutritional security of functional food.

  15. Effects of Brown Rice Extract Treated with Lactobacillus sakei Wikim001 on Osteoblast Differentiation and Osteoclast Formation.

    PubMed

    Kang, Miran; Song, Jung-Hee; Park, Sung-Hee; Lee, Jong-Hee; Park, Hae Woong; Kim, Tae-Woon

    2014-12-01

    Phytic acid (myo-inositol hexakisphosphate) or phytate is considered an anti-nutrient due to the formation of precipitated complexes that strongly reduces the absorption of essential dietary minerals. In this study, brown rice with reduced phytate was made by inoculation with Lactobacillus sakei Wikim001 having high phytase activity. The effects of brown rice extract treated with L. sakei Wikim001 (BR-WK) on osteoblast differentiation and osteoclast formation were investigated. The proliferation of SaOS-2 cells was measured by the MTT assay. Treatment with BR-WK increased cell proliferation by 136% at a concentration of 100 μg/mL. The Alkaline phosphate activity in SaOS-2 cells was 129% higher when BR-WK was processed at a concentration of 100 μg/mL. The proliferation of bone marrow macrophages decreased by nearly 60% in response to treatment with BR-WK. In addition, BR-WK reduced the number of tartrate-resistant acid phosphatase-positive (TRAP(+)) multinucleated cells from bone marrow macrophages. These results indicate that BR-WK stimulates bone formation through its positive action on osteoblast differentiation and function and furthermore, decreases osteoclast differentiation.

  16. Effects of Brown Rice Extract Treated with Lactobacillus sakei Wikim001 on Osteoblast Differentiation and Osteoclast Formation

    PubMed Central

    Kang, Miran; Song, Jung-Hee; Park, Sung-Hee; Lee, Jong-Hee; Park, Hae Woong; Kim, Tae-Woon

    2014-01-01

    Phytic acid (myo-inositol hexakisphosphate) or phytate is considered an anti-nutrient due to the formation of precipitated complexes that strongly reduces the absorption of essential dietary minerals. In this study, brown rice with reduced phytate was made by inoculation with Lactobacillus sakei Wikim001 having high phytase activity. The effects of brown rice extract treated with L. sakei Wikim001 (BR-WK) on osteoblast differentiation and osteoclast formation were investigated. The proliferation of SaOS-2 cells was measured by the MTT assay. Treatment with BR-WK increased cell proliferation by 136% at a concentration of 100 μg/mL. The Alkaline phosphate activity in SaOS-2 cells was 129% higher when BR-WK was processed at a concentration of 100 μg/mL. The proliferation of bone marrow macrophages decreased by nearly 60% in response to treatment with BR-WK. In addition, BR-WK reduced the number of tartrate-resistant acid phosphatase-positive (TRAP+) multinucleated cells from bone marrow macrophages. These results indicate that BR-WK stimulates bone formation through its positive action on osteoblast differentiation and function and furthermore, decreases osteoclast differentiation. PMID:25580402

  17. Dietary phytic acid modulates characteristics of the colonic luminal environment and reduces serum levels of proinflammatory cytokines in rats fed a high-fat diet.

    PubMed

    Okazaki, Yukako; Katayama, Tetsuyuki

    2014-12-01

    Dietary phytic acid (PA; myo-inositol [MI] hexaphosphate) is known to inhibit colon carcinogenesis in rodents. Dietary fiber, which is a negative risk factor of colon cancer, improves characteristics of the colonic environment, such as the content of organic acids and microflora. We hypothesized that dietary PA would improve the colonic luminal environment in rats fed a high-fat diet. To test this hypothesis, rats were fed diets containing 30% beef tallow with 2.04% sodium PA, 0.4% MI, or 1.02% sodium PA + 0.2% MI for 3 weeks. Compared with the control diet, the sodium PA diet up-regulated cecal organic acids, including acetate, propionate, and n-butyrate; this effect was especially prominent for cecal butyrate. The sodium PA + MI diet also significantly increased cecal butyrate, although this effect was less pronounced when compared with the sodium PA diet. The cecal ratio of Lactobacillales, cecal and fecal mucins (an index of intestinal barrier function), and fecal β-glucosidase activity were higher in rats fed the sodium PA diet than in those fed the control diet. The sodium PA, MI, and sodium PA + MI diets decreased levels of serum tumor necrosis factor α, which is a proinflammatory cytokine. Another proinflammatory cytokine, serum interleukin-6, was also down-regulated by the sodium PA and sodium PA + MI diets. These data showed that PA may improve the composition of cecal organic acids, microflora, and mucins, and it may decrease the levels of serum proinflammatory cytokines in rats fed a high-fat, mineral-sufficient diet.

  18. Kinetics, substrate specificity, and stereospecificity of two new protein tyrosine phosphatase-like inositol polyphosphatases from Selenomonas lacticifex.

    PubMed

    Puhl, Aaron A; Greiner, Ralf; Selinger, L Brent

    2008-08-01

    Inositol polyphosphatases (IPPases) play an important role in the metabolism of inositol polyphosphates, a class of molecules involved in signal transduction. Here we characterize 2 new protein tyrosine phosphatase-like IPPases (PhyAsl and PhyBsl) cloned from Selenomonas lacticifex that can hydrolyze myo-inositol hexakisphosphate (InsP6) in vitro. To determine their preferred substrates and stereospecificity of InsP6 dephosphorylation, a combination of kinetic and high-performance ion pair chromatography studies were conducted. Despite only 33% amino acid sequence identity between them, both enzymes display strict specificity for IPP substrates and cleave InsP6 primarily at the D-3-phosphate position (>90%). Furthermore, both enzymes predominantly degrade InsP6 to Ins(2)P via identical and very specific routes of dephosphorylation (3,4,5,6,1). Despite these similarities, PhylAsl is shown to have a slight kinetic preference for the major inositol pentakisphosphate intermediate in its InsP6 hydrolysis pathway, whereas PhyBsl displays a unique and substantial preference for an inositol tetrakisphosphate intermediate.

  19. Biosynthesis and possible functions of inositol pyrophosphates in plants

    PubMed Central

    Williams, Sarah P.; Gillaspy, Glenda E.; Perera, Imara Y.

    2015-01-01

    Inositol phosphates (InsPs) are intricately tied to lipid signaling, as at least one portion of the inositol phosphate signaling pool is derived from hydrolysis of the lipid precursor, phosphatidyl inositol (4,5) bisphosphate. The focus of this review is on the inositol pyrophosphates, which are a novel group of InsP signaling molecules containing diphosphate or triphosphate chains (i.e., PPx) attached to the inositol ring. These PPx-InsPs are emerging as critical players in the integration of cellular metabolism and stress signaling in non-plant eukaryotes. Most eukaryotes synthesize the precursor molecule, myo-inositol (1,2,3,4,5,6)-hexakisphosphate (InsP6), which can serve as a signaling molecule or as storage compound of inositol, phosphorus, and minerals (referred to as phytic acid). Even though plants produce huge amounts of precursor InsP6 in seeds, almost no attention has been paid to whether PPx-InsPs exist in plants, and if so, what roles these molecules play. Recent work has delineated that Arabidopsis has two genes capable of PP-InsP5 synthesis, and PPx-InsPs have been detected across the plant kingdom. This review will detail the known roles of PPx-InsPs in yeast and animal systems, and provide a description of recent data on the synthesis and accumulation of these novel molecules in plants, and potential roles in signaling. PMID:25729385

  20. Phosphatidylinositol-specific phospholipase C from Bacillus cereus combines intrinsic phosphotransferase and cyclic phosphodiesterase activities: A sup 31 P NMR study

    SciTech Connect

    Shashidhar, M.S.; Kuppe, A. ); Volwerk, J.J.; Griffith, O.H.

    1990-09-04

    The inositol phosphate products formed during the cleavage of phosphatidylinositol by phosphatidylinositol-specific phospholipase C from Bacillus cereus were analyzed by {sup 31}P NMR. {sup 31}P NMR spectroscopy can distinguish between the inositol phosphate species and phosphatidylinositol. Chemical shift values (with reference to phosphoric acid) observed are {minus}0.41, 3.62, 4.45, and 16.30 ppm for phosphatidylinositol, myo-inositol 1-monophosphate, myo-inositol 2-monophosphate, and myo-inositol 1,2-cyclic monophosphate, respectively. It is shown that under a variety of experimental conditions this phospholipase C cleaves phosphatidylinositol via an intramolecular phosphotransfer reaction producing diacylglycerol and D-myo-inositol 1,2-cyclic monophosphate. The authors also report the new and unexpected observation that the phosphatidylinositol-specific phospholipase C from B. cereus is able to hydrolyze the inositol cyclic phosphate to form D-myo-inositol 1-monophosphate. The enzyme, therefore, possesses phosphotransferase and cyclic phosphodiesterase activities. The second reaction requires thousandfold higher enzyme concentrations to be observed by {sup 31}P NMR. This reaction was shown to be regiospecific in that only the 1-phosphate was produced and stereospecific in that only D-myo-inositol 1,2-cyclic monophosphate was hydrolyzed. Inhibition with a monoclonal antibody specific for the B.cereus phospholipase C showed that the cyclic phosphodiesterase activity is intrinsic to the bacterial enzyme. They propose a two-step mechanism for the phosphatidyl-inositol-specific phospholipase C from B. cereus involving sequential phosphotransferase and cyclic phosphodiesterase activities. This mechanism bears a resemblance to the well-known two-step mechanism of pancreatic ribonuclease, RNase A.

  1. Reduced gamma-aminobutyric acid is associated with emotional and behavioral problems in Prader-Willi syndrome.

    PubMed

    Rice, Lauren J; Lagopoulos, Jim; Brammer, Michael; Einfeld, Stewart L

    2016-12-01

    Prader-Willi syndrome (PWS) is characterized by infantile hypotonia, hypogonadism, small hands and feet, distinct facial features and usually intellectual impairment. The disorder is associated with severe behavioral disturbances which include hyperphagia leading to morbid obesity, temper outbursts, skin-picking, and compulsive behaviors. While the brain mechanisms that underpin these disturbances are unknown these behaviors suggest a lack of inhibition and thus gamma-aminobutyric acid (GABA), the main inhibitory neurotransmitter may be implicated. In the present study, we investigated in vivo brain GABA and its relationship with emotion and behavior in individuals with PWS. Single voxel proton magnetic resonance spectroscopy (1H-MRS) was performed on 15 individuals with PWS and 15 age- and gender-matched typically developing controls. GABA levels were measured in the parieto-occipital lobe. All other metabolite levels (N-acetyl aspartate, myo-Inositol, glutathione, glutamate, and glutamine + glutamate) were measured in the anterior cingulate cortex (ACC). GABA levels were significantly lower in the participants with PWS who had clinically significant emotional and behavioral problems relative to typically developing control participants and participants with PWS who did not have emotional and behavioral problems within the clinically significant range. GABA levels were negatively correlated with total behavioral problem scores as well as temper outbursts, skin-picking, depression, social relating difficulties, and a tendency to be self-absorbed. Our data suggests that alterations of the GABAergic system may play an important role in aspects of the pathophysiology of PWS. Pathological mechanism found in PWS may be relevant to understanding the control of similar behaviors in the general population. © 2016 Wiley Periodicals, Inc.

  2. Inositol hexakisphosphate kinase 1 (IP6K1) activity is required for cytoplasmic dynein-driven transport

    PubMed Central

    Chanduri, Manasa; Rai, Ashim; Malla, Aushaq Bashir; Wu, Mingxuan; Fiedler, Dorothea; Mallik, Roop; Bhandari, Rashna

    2016-01-01

    Inositol pyrophosphates, such as diphosphoinositol pentakisphosphate (IP7), are conserved eukaryotic signaling molecules that possess pyrophosphate and monophosphate moieties. Generated predominantly by inositol hexakisphosphate kinases (IP6Ks), inositol pyrophosphates can modulate protein function by posttranslational serine pyrophosphorylation. Here, we report inositol pyrophosphates as novel regulators of cytoplasmic dynein-driven vesicle transport. Mammalian cells lacking IP6K1 display defects in dynein-dependent trafficking pathways, including endosomal sorting, vesicle movement, and Golgi maintenance. Expression of catalytically active but not inactive IP6K1 reverses these defects, suggesting a role for inositol pyrophosphates in these processes. Endosomes derived from slime mold lacking inositol pyrophosphates also display reduced dynein-directed microtubule transport. We demonstrate that Ser51 in the dynein intermediate chain (IC) is a target for pyrophosphorylation by IP7, and this modification promotes the interaction of the IC N-terminus with the p150Glued subunit of dynactin. IC–p150Glued interaction is decreased, and IC recruitment to membranes is reduced in cells lacking IP6K1. Our study provides the first evidence for the involvement of IP6Ks in dynein function and proposes that inositol pyrophosphate-mediated pyrophosphorylation may act as a regulatory signal to enhance dynein-driven transport. PMID:27474409

  3. Dietary supplementation with n-3 fatty acids from weaning limits brain biochemistry and behavioural changes elicited by prenatal exposure to maternal inflammation in the mouse model.

    PubMed

    Li, Q; Leung, Y O; Zhou, I; Ho, L C; Kong, W; Basil, P; Wei, R; Lam, S; Zhang, X; Law, A C K; Chua, S E; Sham, P C; Wu, E X; McAlonan, G M

    2015-09-22

    Prenatal exposure to maternal immune activation (MIA) increases the risk of schizophrenia and autism in the offspring. The MIA rodent model provides a valuable tool to directly test the postnatal consequences of exposure to an early inflammatory insult; and examine novel preventative strategies. Here we tested the hypotheses that behavioural differences in the MIA mouse model are accompanied by in vivo and ex vivo alterations in brain biochemistry; and that these can be prevented by a post-weaning diet enriched with n-3 polyunsaturated fatty acid (PUFA). The viral analogue PolyI:C (POL) or saline (SAL) was administered to pregnant mice on gestation day 9. Half the resulting male offspring (POL=21; SAL=17) were weaned onto a conventional lab diet (n-6 PUFA); half were weaned onto n-3 PUFA-enriched diet. In vivo magnetic resonance spectroscopy measures were acquired prior to behavioural tests; glutamic acid decarboxylase 67 (GAD67) and tyrosine hydroxylase protein levels were measured ex vivo. The main findings were: (i) Adult MIA-exposed mice fed a standard diet had greater N-acetylaspartate/creatine (Cr) and lower myo-inositol/Cr levels in the cingulate cortex in vivo. (ii) The extent of these metabolite differences was correlated with impairment in prepulse inhibition. (iii) MIA-exposed mice on the control diet also had higher levels of anxiety and altered levels of GAD67 ex vivo. (iv) An n-3 PUFA diet prevented all the in vivo and ex vivo effects of MIA observed. Thus, n-3 PUFA dietary enrichment from early life may offer a relatively safe and non-toxic approach to limit the otherwise persistent behavioural and biochemical consequences of prenatal exposure to inflammation. This result may have translational importance.

  4. Structural Characteristics and Catalytic Mechanism of Bacillus β-Propeller Phytases.

    PubMed

    Balaban, N P; Suleimanova, A D; Valeeva, L R; Shakirov, E V; Sharipova, M R

    2016-08-01

    β-Propeller phytases of Bacillus are unique highly conservative and highly specific enzymes capable of cleaving insoluble phytate compounds. In this review, we analyzed data on the properties of these enzymes, their differences from other phytases, and their unique spatial structures and substrate specificities. We considered influences of different factors on the catalytic activity and thermostability of these enzymes. There are few data on the hydrolysis mechanism of these enzymes, which makes it difficult to analyze their mechanism of action and their final products. We analyzed the available data on hydrolysis by β-propeller phytases of calcium complexes with myo-inositol hexakisphosphate.

  5. Phytate (Inositol Hexakisphosphate) in Soil and Phosphate Acquisition from Inositol Phosphates by Higher Plants. A Review

    PubMed Central

    Gerke, Jörg

    2015-01-01

    Phosphate (P) fixation to the soil solid phase is considered to be important for P availability and is often attributed to the strong binding of orthophosphate anion species. However, the fixation and subsequent immobilization of inositolhexa and pentaphosphate isomers (phytate) in soil is often much stronger than that of the orthosphate anion species. The result is that phytate is a main organic P form in soil and the dominating form of identifiable organic P. The reasons for the accumulation are not fully clear. Two hypothesis can be found in the literature in the last 20 years, the low activity of phytase (phosphatases) in soil, which makes phytate P unavailable to the plant roots, and, on the other hand, the strong binding of phytate to the soil solid phase with its consequent stabilization and accumulation in soil. The hypothesis that low phytase activity is responsible for phytate accumulation led to the development of genetically modified plant genotypes with a higher expression of phytase activity at the root surface and research on the effect of a higher phytate activity on P acquisition. Obviously, this hypothesis has a basic assumption, that the phytate mobility in soil is not the limiting step for P acquisition of higher plants from soil phytate. This assumption is, however, not justified considering the results on the sorption, immobilization and fixation of phytate to the soil solid phase reported in the last two decades. Phytate is strongly bound, and the P sorption maximum and probably the sorption strength of phytate P to the soil solid phase is much higher, compared to that of orthophosphate P. Mobilization of phytate seems to be a promising step to make it available to the plant roots. The excretion of organic acid anions, citrate and to a lesser extend oxalate, seems to be an important way to make phytate P available to the plants. Phytase activity at the root surface seems not be the limiting step in P acquisition from phytate. Phytate is not

  6. Genetic analysis of two OsLpa1-like genes in Arabidopsis reveals that only one is required for wild-type seed phytic acid levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytic acid (inositol-1,2,3,4,5,6-hexakisphosphate or InsP6) is the primary storage form of phosphorus in plant seeds. The rice OsLpa1 encodes a novel protein required for wild-type levels of seed InsP6 and was identified from a low phytic acid (lpa) mutant exhibiting a 45-50% reduction in seed InsP...

  7. Mycobacterium avium subsp. paratuberculosis (Map) Fatty Acids Profile Is Strain-Dependent and Changes Upon Host Macrophages Infection

    PubMed Central

    Alonso-Hearn, Marta; Abendaño, Naiara; Ruvira, Maria A.; Aznar, Rosa; Landin, Mariana; Juste, Ramon A.

    2017-01-01

    Johne's disease is a chronic granulomatous enteritis of ruminants caused by the intracellular bacterium Mycobacterium avium subsp. paratuberculosis (Map). We previously demonstrated that Map isolates from sheep persisted within host macrophages in lower CFUs than cattle isolates after 7 days of infection. In the current study, we hypothesize that these phenotypic differences between Map isolates may be driven be the fatty acids (FAs) present on the phosphadidyl-1-myo-inositol mannosides of the Map cell wall that mediate recognition by the mannose receptors of host macrophages. FAs modifications may influence Map's envelope fluidity ultimately affecting pathogenicity. To test this hypothesis, we investigated the responses of two Map isolates from cattle (K10 isolate) and sheep (2349/06-1) to the bovine and ovine macrophage environment by measuring the FAs content of extracellular and intracellular bacteria. For this purpose, macrophages cell lines of bovine (BOMAC) and ovine (MOCL-4) origin were infected with the two isolates of Map for 4 days at 37°C. The relative FAs composition of the two isolates recovered from infected BOMAC and MOCL-4 cells was determined by gas chromatography and compared with that of extracellular bacteria and that of bacteria grown in Middlebrook 7H9 medium. Using this approach, we demonstrated that the FAs composition of extracellular and 7H9-grown bacteria was highly conserved within each Map isolate, and statistically different from that of intracellular bacteria. Analysis of FAs composition from extracellular bacteria enabled the distinction of the two Map strains based on the presence of the tuberculostearic acid (18:0 10Me) exclusively in the K10 strain of Map. In addition, significant differences in the content of Palmitic acid and cis-7 Palmitoleic acid between both isolates harvested from the extracellular environment were observed. Once the infection established itself in BOMAC and MOCL-4 cells, the FAs profiles of both Map

  8. Pathway of phytate dephosphorylation by beta-propeller phytases of different origins.

    PubMed

    Greiner, Ralf; Lim, Boon L; Cheng, Chiwai; Carlsson, Nils-Gunnar

    2007-04-01

    Using a combination of high-performance ion chromatography analysis and kinetic studies, the pathway of myo-inositol hexakisphosphate dephosphorylation by the beta-propeller phytase of Shewanella oneidensis was established, which was then compared with that of Bacillus subtilis 168, Bacillus amyloliquefaciens ATCC 15841, and B. amyloliquefaciens 45 beta-propeller phytases. The data demonstrate that all of these beta-propeller phytases dephosphorylate myo-inositol hexakisphosphate in a stereospecific way by sequential removal of phosphate groups via d-Ins(1,2,4,5,6)P5, Ins(2,4,5,6)P4 to finally Ins(2,4,6)P3. Thus, the beta-propeller phytases prefer the hydrolysis of every second phosphate over that of adjacent ones. This finding does not support previous phytate degradation models proposed by J. Kerovuo, J. Rouvinen, and F. Hatzack (2000. Biochem. J. 352: 623-628) and R. Greiner, A. Farouk, M. Larsson Alminger, and N.G. Carlsson (2002. Can. J. Microbiol. 48: 986-994), but seems to fit with the structural model given by S. Shin, N.C. Ha, B.C. Oh, T.K. Oh, and B.H. Oh (2001. Structure, 9: 851-858).

  9. Myo-inositol phosphate synthase expression in the European eel (Anguilla anguilla) and Nile tilapia (Oreochromis niloticus): effect of seawater acclimation.

    PubMed

    Kalujnaia, Svetlana; Hazon, Neil; Cramb, Gordon

    2016-08-01

    A single MIPS gene (Isyna1/Ino1) exists in eel and tilapia genomes with a single myo-d-inositol 3-phosphate synthase (MIPS) transcript identified in all eel tissues, although two MIPS spliced variants [termed MIPS(s) and MIPS(l)] are found in all tilapia tissues. The larger tilapia transcript [MIPS(l)] results from the inclusion of the 87-nucleotide intron between exons 5 and 6 in the genomic sequence. In most tilapia tissues, the MIPS(s) transcript exhibits much higher abundance (generally >10-fold) with the exception of white skeletal muscle and oocytes, in which the MIPS(l) transcript predominates. SW acclimation resulted in large (6- to 32-fold) increases in mRNA expression for both MIPS(s) and MIPS(l) in all tilapia tissues tested, whereas in the eel, changes in expression were limited to a more modest 2.5-fold increase and only in the kidney. Western blots identified a number of species- and tissue-specific immunoreactive MIPS proteins ranging from 40 to 67 kDa molecular weight. SW acclimation failed to affect the abundance of any immunoreactive protein in any tissue tested from the eel. However, a major 67-kDa immunoreactive protein (presumed to be MIPS) found in tilapia tissues exhibited 11- and 54-fold increases in expression in gill and fin samples from SW-acclimated fish. Immunohistochemical investigations revealed specific immunoreactivity in the gill, fin, skin, and intestine taken from only SW-acclimated tilapia. Immunofluorescence indicated that MIPS was expressed within gill chondrocytes and epithelial cells of the primary filaments, basal epithelial cell layers of the skin and fin, the cytosol of columnar intestinal epithelial and mucous cells, as well as unknown entero-endocrine-like cells.

  10. Myo-inositol phosphate synthase expression in the European eel (Anguilla anguilla) and Nile tilapia (Oreochromis niloticus): effect of seawater acclimation

    PubMed Central

    Kalujnaia, Svetlana; Hazon, Neil

    2016-01-01

    A single MIPS gene (Isyna1/Ino1) exists in eel and tilapia genomes with a single myo-d-inositol 3-phosphate synthase (MIPS) transcript identified in all eel tissues, although two MIPS spliced variants [termed MIPS(s) and MIPS(l)] are found in all tilapia tissues. The larger tilapia transcript [MIPS(l)] results from the inclusion of the 87-nucleotide intron between exons 5 and 6 in the genomic sequence. In most tilapia tissues, the MIPS(s) transcript exhibits much higher abundance (generally >10-fold) with the exception of white skeletal muscle and oocytes, in which the MIPS(l) transcript predominates. SW acclimation resulted in large (6- to 32-fold) increases in mRNA expression for both MIPS(s) and MIPS(l) in all tilapia tissues tested, whereas in the eel, changes in expression were limited to a more modest 2.5-fold increase and only in the kidney. Western blots identified a number of species- and tissue-specific immunoreactive MIPS proteins ranging from 40 to 67 kDa molecular weight. SW acclimation failed to affect the abundance of any immunoreactive protein in any tissue tested from the eel. However, a major 67-kDa immunoreactive protein (presumed to be MIPS) found in tilapia tissues exhibited 11- and 54-fold increases in expression in gill and fin samples from SW-acclimated fish. Immunohistochemical investigations revealed specific immunoreactivity in the gill, fin, skin, and intestine taken from only SW-acclimated tilapia. Immunofluorescence indicated that MIPS was expressed within gill chondrocytes and epithelial cells of the primary filaments, basal epithelial cell layers of the skin and fin, the cytosol of columnar intestinal epithelial and mucous cells, as well as unknown entero-endocrine-like cells. PMID:27252471

  11. Dissolved organic phosphorus speciation in the waters of the Tamar estuary (SW England)

    NASA Astrophysics Data System (ADS)

    Monbet, Phil; McKelvie, Ian D.; Worsfold, Paul J.

    2009-02-01

    The speciation of dissolved organic phosphorus (DOP) in the temperate Tamar estuary of SW England is described. Eight stations from the riverine to marine end-members were sampled during four seasonal campaigns in 2007 and the DOP pool in the water column and sediment porewater was characterized and quantified using a flow injection manifold after sequential enzymatic hydrolysis. This enabled the enzymatically hydrolysable phosphorus (EHP) fraction and its component labile monoester phosphates, diester phosphates and a phytase-hydrolysable fraction that includes myo-inositol hexakisphosphate (phytic acid), to be determined and compared with the total DOP, dissolved reactive phosphorus (DRP) and total dissolved phosphorus (TDP) pools. The results showed that the DOP pool in the water column varied temporally and spatially within the estuary (1.1-22 μg L -1) and constituted 6-40% of TDP. The EHP fraction of DOP ranged from 1.1-15 μg L -1 and represented a significant and potentially bioavailable phosphorus fraction. Furthermore the spatial profiles of the three components of the EHP pool generally showed non-conservative behavior along the salinity gradient, with apparent internal estuarine sources. Porewater profiles followed broadly similar trends but were notably higher at the marine station throughout the year. In contrast to soil organic phosphorus profiles, the labile monoester phosphate fraction was the largest component, with diester phosphates also prevalent. Phytic acid concentrations were higher in the lower estuary, possibly due to salinity induced desorption processes. The EHP fraction is not commonly determined in aquatic systems due to the lack of a suitable measurement technique and the Tamar results reported here have important implications for phosphorus biogeochemistry, estuarine ecology and the development of efficient strategies for limiting the effects of phosphorus on water quality.

  12. Increased levels of inositol hexakisphosphate (InsP6) protect HEK293 cells from tumor necrosis factor (alpha)- and Fas-induced apoptosis.

    PubMed

    Verbsky, John; Majerus, Philip W

    2005-08-12

    The overexpression of inositol 1,3,4-trisphosphate 5/6-kinase has recently been shown to protect HEK293 cells from tumor necrosis factor alpha (TNF(alpha))-induced apoptosis. This overexpression leads to an increase in the levels of both inositol 1,3,4,5,6-pentakisphosphate (InsP5) and inositol 1,2,3,4,5,6-hexakisphosphate (InsP6). Cells that overexpress InsP5 2-kinase have increased levels of InsP6 and are also protected from TNFalpha-induced apoptosis; furthermore, cells that express an RNA interference construct to the 2-kinase are deficient in InsP6 and are sensitized to TNFalpha-induced apoptosis. Therefore the protective effect of 5/6-kinase on TNFalpha-mediated apoptosis is due to an increase of InsP6 or to a metabolite derived from InsP6. Furthermore, we find that the InsP6 also protects from Fas-mediated apoptosis. No effect was seen in the endocytic rate of transferrin receptor, caspase 8 activity, or TNF receptor number at the cell surface. Cells that overexpress 2-kinase do show an increase in the amount of receptor-interacting protein (RIP), while cells with reduced InsP6 levels show relatively less RIP, providing a possible mechanism for the effect on apoptosis.

  13. Rapid transport and transformation of phosphorus species during the leaching of poultry manure amended soil

    NASA Astrophysics Data System (ADS)

    Giles, Courtney; Cade-Menun, Barbara; Liu, Corey; Hill, Jane

    2015-04-01

    The loss of phosphorus (P) from soils due to leaching is a major concern in heavily fertilized agricultural regions. The mobility and transformation of P species will depend on the source of manure fertilizer, leaching regime, and the extent of soil P saturation within the soil profile. We investigate spatial and temporal changes in the distribution of P species within a poultry manure-amended soil at two depths (0-5, 10-15 cm) as well as leachate P fractions during 10 weeks of leaching. Leachate P was primarily composed of dissolved fractions (soluble reactive P; dissolved unreactive P) and reached a maximum in the fourth week of leaching. In soils, the degree of P saturation (80%) and water extractable P (9 mg kg-1) were also greatest in week 4. 31P NMR spectra of the 0-5 cm depth indicate that surface soils were most similar to the poultry manure in week 4. During peak leaching, the proportion of orthophosphate (OrthoP) at the soil surface (0-5 cm; 80%) was greater than that from the lowest depth (10-15 cm; 72%), which contained relatively larger proportions of monoester-(17%) and diester-P classes (10%). Poultry manure likely contributed to the mobile pool of P species, including OrthoP, myo-inositol hexakisphosphate (myo-IHP), and nucleic acids. The appearance of neo- and D-chiro-IHP, as well as phospholipid signals during the leaching period indicate possible short-term (<10 week) contributions of organic P to the generation and leaching of OrthoP, under P-saturated conditions. Further work is needed to determine how fertilization and leaching will affect the mobility and transformation of P species across a wider range of soil types. Keywords: Phytate, organic phosphorus, degree of phosphorus saturation, soil, leachate, poultry manure

  14. Arabidopsis thaliana VTC4 encodes L-galactose-1-P phosphatase, a plant ascorbic acid biosynthetic enzyme.

    PubMed

    Conklin, Patricia L; Gatzek, Stephan; Wheeler, Glen L; Dowdle, John; Raymond, Marjorie J; Rolinski, Susanne; Isupov, Mikhail; Littlechild, Jennifer A; Smirnoff, Nicholas

    2006-06-09

    In plants, a proposed ascorbate (vitamin C) biosynthesis pathway occurs via GDP-D-mannose (GDP-D-Man), GDP-L-galactose (GDP-L-Gal), and L-galactose. However, the steps involved in the synthesis of L-Gal from GDP-L-Gal in planta are not fully characterized. Here we present evidence for an in vivo role for L-Gal-1-P phosphatase in plant ascorbate biosynthesis. We have characterized a low ascorbate mutant (vtc4-1) of Arabidopsis thaliana, which exhibits decreased ascorbate biosynthesis. Genetic mapping and sequencing of the VTC4 locus identified a mutation (P92L) in a gene with predicted L-Gal-1-P phosphatase activity (At3g02870). Pro-92 is within a beta-bulge that is conserved in related myo-inositol monophosphatases. The mutation is predicted to disrupt the positioning of catalytic amino acid residues within the active site. Accordingly, L-Gal-1-P phosphatase activity in vtc4-1 was approximately 50% of wild-type plants. In addition, vtc4-1 plants incorporate significantly more radiolabel from [2-(3)H]Man into L-galactosyl residues suggesting that the mutation increases the availability of GDP-L-Gal for polysaccharide synthesis. Finally, a homozygous T-DNA insertion line, which lacks a functional At3g02870 gene product, is also ascorbate-deficient (50% of wild type) and deficient in L-Gal-1-P phosphatase activity. Genetic complementation tests revealed that the insertion mutant and VTC4-1 are alleles of the same genetic locus. The significantly lower ascorbate and perturbed L-Gal metabolism in vtc4-1 and the T-DNA insertion mutant indicate that L-Gal-1-P phosphatase plays a role in plant ascorbate biosynthesis. The presence of ascorbate in the T-DNA insertion mutant suggests there is a bypass to this enzyme or that other pathways also contribute to ascorbate biosynthesis.

  15. Phytase activity as a novel metabolic feature in Bifidobacterium.

    PubMed

    Haros, Monica; Bielecka, Maria; Sanz, Yolanda

    2005-06-15

    Phytase activity has been detected for the first time in Bifidobacterium spp. These bacteria were able to dephosphorylate phytic acid (myo-inositol hexaphosphate, IP(6)) and generate several myo-inositol phosphate intermediates (IP(3)-IP(5)). B. globosum and B. pseudocatenulatum were optimally active at neutral-alkaline pH and B. adolescentis, B. angulatum and B. longum at acid pH. B. pseudocatenulatum showed the highest levels of phytase activity. This species produced maximum activity in the exponential phase of growth and when fructo-oligosaccharides were used as carbon source in the culture medium. The potential role of phytase activity from Bifidobacterium spp. in the reduction of the antinutritional properties of IP(6) is discussed.

  16. Novel Phytases from Bifidobacterium pseudocatenulatum ATCC 27919 and Bifidobacterium longum subsp. infantis ATCC 15697

    PubMed Central

    Tamayo-Ramos, Juan Antonio; Sanz-Penella, Juan Mario; Yebra, María J.

    2012-01-01

    Two novel phytases have been characterized from Bifidobacterium pseudocatenulatum and Bifidobacterium longum subsp. infantis. The enzymes belong to a new subclass within the histidine acid phytases, are highly specific for the hydrolysis of phytate, and render myo-inositol triphosphate as the final hydrolysis product. They represent the first phytases characterized from this group of probiotic microorganisms, opening the possibilities for their use in the processing of high-phytate-content foods. PMID:22582052

  17. Novel phytases from Bifidobacterium pseudocatenulatum ATCC 27919 and Bifidobacterium longum subsp. infantis ATCC 15697.

    PubMed

    Tamayo-Ramos, Juan Antonio; Sanz-Penella, Juan Mario; Yebra, María J; Monedero, Vicente; Haros, Monika

    2012-07-01

    Two novel phytases have been characterized from Bifidobacterium pseudocatenulatum and Bifidobacterium longum subsp. infantis. The enzymes belong to a new subclass within the histidine acid phytases, are highly specific for the hydrolysis of phytate, and render myo-inositol triphosphate as the final hydrolysis product. They represent the first phytases characterized from this group of probiotic microorganisms, opening the possibilities for their use in the processing of high-phytate-content foods.

  18. Ultraviolet A induces transport of compatible organic osmolytes in human dermal fibroblasts.

    PubMed

    Warskulat, Ulrich; Brookmann, Stefanie; Felsner, Ingo; Brenden, Heidi; Grether-Beck, Susanne; Häussinger, Dieter

    2008-12-01

    Compatible organic osmolytes, such as betaine, myo-inositol and taurine, are involved in cell protection. Human dermal fibroblasts accumulate these osmolytes and express mRNA specific for their transporting systems betaine-/gamma-amino-n-butyric acid (GABA) transporter (BGT-1), sodium-dependent myo-inositol transporter (SMIT) and taurine transporter (TAUT). Taurine uptake was about sixfold higher than that of betaine and myo-inositol. Compared with normoosmotic (305 mOsm/l) control, hyperosmotic exposure (405 mOsm/l) led to a twofold induction of osmolyte uptake. Ultraviolet A (UVA) upregulated osmolyte transporter mRNA levels and increased osmolyte uptake. Taurine inhibited UVA-induced interleukin-6 (Il-6) mRNA expression by 40%. Furthermore, Il-6 accumulation in the supernatants of UVA-irradiated dermal fibroblasts was much slower when cells were preincubated with taurine. These data indicate that taurine accumulation seems to be part of the fibroblast response to UVA radiation and may protect against UVA-induced Il-6 overexpression.

  19. An insect growth inhibitor--lufenuron--enhances albendazole activity against hydatid cyst.

    PubMed

    Breijo, Martín; Isnardi, Fernanda; Brauer, Mónica; Schenker, Rudolf; Ferrari, Mariana; Ferreira, Ana M

    2011-09-27

    The aim of this work was to evaluate the potential of lufenuron, a benzylphenylurea with ability to interfere with the formation of insect exoskeleton, as a therapeutic drug for larval echinococcosis (hydatid disease). For this purpose lufenuron, alone or in combination with albendazole, was administered to CD1 mice bearing Echinococcus granulosus hydatid cysts in the peritoneal cavity. Neither of the drugs alone was able to exert parasiticidal effects. However, in combination with albendazole, lufenuron reduced the growth of cysts (30-40% in cyst diameter respect to control, p<0.05). This effect was associated with ultrastructural alterations of the hydatid cyst wall and a reduction of the content of myo-inositol-hexakisphosphate, the major component of the electron dense granules of the laminated layer. Overall, this work provides evidence that lufenuron could represent a useful compound for the use in chemotherapy against larval echinococcosis, by enhancing albendazole parasiticidal activity.

  20. Simultaneous iron, zinc, sulfur and phosphorus speciation analysis of barley grain tissues using SEC-ICP-MS and IP-ICP-MS.

    PubMed

    Persson, Daniel P; Hansen, Thomas H; Laursen, Kristian H; Schjoerring, Jan K; Husted, Søren

    2009-09-01

    The increasing prevalence of iron (Fe) and zinc (Zn) deficiencies in human populations worldwide has stressed the need for more information about the distribution and chemical speciation of these elements in cereal products. In order to investigate these aspects, barley grains were fractionated into awns, embryo, bran and endosperm and analysed for Fe and Zn. Simultaneously, phosphorus (P) and sulfur (S) were determined since these elements are major constituents of phytic acid and proteins, respectively, compounds which are potentially involved in Fe and Zn binding. A novel analytical method was developed in which oxygen was added to the octopole reaction cell of the ICP-MS. This approach greatly improved the sensitivity of sulfur, measured as (48)SO(+). Simultaneously, Fe was measured as (72)FeO(+), P as (47)PO(+), and Zn as (66)Zn(+), enabling sensitive and simultaneous analysis of these four elements. The highest concentrations of Zn, Fe, S and P were found in the bran and embryo fractions. Further analysis of the embryo using SEC-ICP-MS revealed that the speciation of Fe and Zn differed. The majority of Fe co-eluted with P as a species with the apparent mass of 12.3 kDa, whereas the majority of Zn co-eluted with S as a 3 kDa species, devoid of any co-eluting P. Subsequent ion pairing chromatography of the Fe/P peak showed that phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate: IP(6)) was the main Fe binding ligand, with the stoichiometry Fe(4)(IP(6))(18). When incubating the embryo tissue with phytase, the enzyme responsible for degradation of phytic acid, the extraction efficiency of both Fe and P was doubled, whereas that of Zn and S was unaffected. Protein degradation on the other hand, using protease XIV, boosted the extraction of Zn and S, but not that of Fe and P. It is concluded that Fe and Zn have a different speciation in cereal grain tissues; Zn appears to be mainly bound to peptides, while Fe is mainly associated with phytic acid.

  1. Organic Phosphorus Characterisation in Agricultural Soils by Enzyme Addition Assays

    NASA Astrophysics Data System (ADS)

    Jarosch, Klaus; Frossard, Emmanuel; Bünemann, Else K.

    2013-04-01

    Phosphorus (P) is a non-renewable resource and it is a building block of many molecules indispensable for life. Up to 80 per cent of total soil P can be in organic form. Hydrolysability and thereby availability to plants and microorganisms differ strongly among the multitude of chemical forms of soil organic P. A recent approach to characterise organic P classes is the addition of specific enzymes which hydrolyse organic P to inorganic orthophosphate, making it detectable by colorimetry. Based on the substrate specificity of the added enzymes, conclusions about the hydrolysed forms of organic P can then be made. The aim of this study was to determine the applicability of enzyme addition assays for the characterisation of organic P species in soil:water suspensions of soils with differing properties. To this end, ten different soil samples originating from four continents, with variable pH (in water) values (4.2-8.0), land management (grassland or cropped land) and P fertilization intensity were analysed. Three different enzymes were used (acid phosphatase, nuclease and phytase). Acid phosphatase alone or in combination with nuclease was applied to determine the content of P in simple monoesters (monoester-like P) and P in DNA (DNA-like P), while P hydrolysed from myo-inositol hexakisphosphate (Ins6P-like P) was calculated from P release after incubation with phytase minus P release by acid phosphatase. To reduce sorption of inorganic P on soil particles of the suspension, especially in highly weathered soils, soil specific EDTA additions were determined in extensive pre-tests. The results of these pre-tests showed that recoveries of at least 30 per cent could be achieved in all soils. Thus, detection of even small organic P pools, such as DNA-like P, was possible in all soils if a suitable EDTA concentration was chosen. The enzyme addition assays provided information about the hydrolysable quantities of the different classes of soil organic P compounds as affected

  2. Developing seeds of Arabidopsis store different minerals in two types of vacuoles and in the endoplasmic reticulum.

    PubMed

    Otegui, Marisa S; Capp, Roberta; Staehelin, L Andrew

    2002-06-01

    Mineral-accumulating compartments in developing seeds of Arabidopsis were studied using high-pressure-frozen/freeze-substituted samples. Developing seeds store minerals in three locations: in the protein storage vacuoles of the embryo, and transiently in the endoplasmic reticulum (ER) and vacuolar compartments of the chalazal endosperm. Energy dispersive x-ray spectroscopy and enzyme treatments suggest that the minerals are stored as phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate) salts in all three compartments, although they differ in cation composition. Whereas embryo globoids contain Mg, K, and Ca as cations, the chalazal ER deposits show high levels of Mn, and the chalazal vacuolar deposits show high levels of Zn. The appearance of the first Zn-phytate crystals coincides with the formation of network-like extensions of the chalazal vacuoles. The core of these networks consists of a branched network of tubular ER membranes, which are separated from the delineating tonoplast membranes by a layer of cytosolic material. Degradation of the networks starts with the loss of the cytosol and is followed by the retraction of the ER, generating a network of collapsed tonoplast membranes that are resorbed. Studies of fertilized fis2 seeds, which hyperaccumulate Zn-phytate crystals in the chalazal vacuolar compartments, suggest that only the intact network is active in mineral sequestration. Mineral determination analysis and structural observations showed that Zn and Mn are mobilized from the endosperm to the embryo at different developmental stages. Thus, Zn appears to be removed from the endosperm at the late globular stage, and Mn stores appear to be removed at the late bent-cotyledon stage of embryo development. The disappearance of the Mn-phytate from the endosperm coincides with the accumulation of two major Mn binding proteins in the embryo, the 33-kD protein from the oxygen-evolving complex of photosystem II and the Mn superoxide dismutase. The possible

  3. Developing Seeds of Arabidopsis Store Different Minerals in Two Types of Vacuoles and in the Endoplasmic Reticulum

    PubMed Central

    Otegui, Marisa S.; Capp, Roberta; Staehelin, L. Andrew

    2002-01-01

    Mineral-accumulating compartments in developing seeds of Arabidopsis were studied using high-pressure-frozen/freeze-substituted samples. Developing seeds store minerals in three locations: in the protein storage vacuoles of the embryo, and transiently in the endoplasmic reticulum (ER) and vacuolar compartments of the chalazal endosperm. Energy dispersive x-ray spectroscopy and enzyme treatments suggest that the minerals are stored as phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate) salts in all three compartments, although they differ in cation composition. Whereas embryo globoids contain Mg, K, and Ca as cations, the chalazal ER deposits show high levels of Mn, and the chalazal vacuolar deposits show high levels of Zn. The appearance of the first Zn-phytate crystals coincides with the formation of network-like extensions of the chalazal vacuoles. The core of these networks consists of a branched network of tubular ER membranes, which are separated from the delineating tonoplast membranes by a layer of cytosolic material. Degradation of the networks starts with the loss of the cytosol and is followed by the retraction of the ER, generating a network of collapsed tonoplast membranes that are resorbed. Studies of fertilized fis2 seeds, which hyperaccumulate Zn-phytate crystals in the chalazal vacuolar compartments, suggest that only the intact network is active in mineral sequestration. Mineral determination analysis and structural observations showed that Zn and Mn are mobilized from the endosperm to the embryo at different developmental stages. Thus, Zn appears to be removed from the endosperm at the late globular stage, and Mn stores appear to be removed at the late bent-cotyledon stage of embryo development. The disappearance of the Mn-phytate from the endosperm coincides with the accumulation of two major Mn binding proteins in the embryo, the 33-kD protein from the oxygen-evolving complex of photosystem II and the Mn superoxide dismutase. The possible

  4. 1D-myo-inositol 1,4,5-trisphosphate dephosphorylation by rat enterocytes involves an intracellular 5-phosphatase and non-specific phosphatase activity at the cell surface.

    PubMed Central

    Rubiera, C; Velasco, G; Michell, R H; Lazo, P S; Shears, S B

    1988-01-01

    We studied the dephosphorylation of Ins(1,4,5)P3 (inositol 1,4,5-trisphosphate) by permeabilized rat intestinal epithelial cells incubated in a medium resembling intracellular ionic strength and pH. Saponin-permeabilized cells rapidly dephosphorylated Ins(1,4,5)P3 to a mixture of three InsP2 (inositol bisphosphate) isomers, namely Ins(1,4)P2, Ins(1,5)P2 and Ins(4,5)P2. These products were identified by h.p.l.c. analysis after dephosphorylation of both 3H- and 32P-labelled Ins(1,4,5)P3. Ins(1,4)P2 accumulated to about half of the concentration attained by Ins(1,5)P2 and Ins(4,5)P2. Ins(1,4,5)P3 dephosphorylation was inhibited, by up to 75%, by 10 mM-glucose 6-phosphate. In these conditions Ins(1,4)P2 became the predominant product, indicating that glucose 6-phosphate inhibited non-specific dephosphorylation of Ins(1,4,5)P3, at least at the 1- and 4-phosphate groups. Ins(1,4)P2 was further dephosphorylated, and the major InsP (inositol monophosphate) product was Ins4P. Most of the glucose 6-phosphate-inhibitable Ins(1,4,5)P3 phosphatase activity was exposed on the cell surface. The glucose 6-phosphate-insensitive Ins(1,4,5)P3 5-phosphatase activity was not detected until the cells were permeabilized with saponin. This intracellular 5-phosphatase activity was: (i) predominantly associated with the particulate portion of the cell; (ii) strongly inhibited by 10 mM-2,3-bisphosphoglycerate; (iii) insensitive to 50 mM-Li+. Therefore the Ins(1,4,5)P3 5-phosphatase activity in enterocytes appears similar to the 5-phosphatase that has been characterized in a number of cell types. PMID:2848503

  5. Ruthenium(III) catalyzed oxidation of sugar alcohols by dichloroisocyanuric acid—A kinetic study

    NASA Astrophysics Data System (ADS)

    Lakshman Kumar, Y.; Venkata Nadh, R.; Radhakrishnamurti, P. S.

    2016-02-01

    Kinetics of ruthenium(III) catalyzed oxidation of biologically important sugar alcohols (myo-inositol, D-sorbitol, and D-mannitol) by dichloroisocyanuric acid was carried out in aqueous acetic acid—perchloric medium. The reactions were found to be first order in case of oxidant and ruthenium(III). Zero order was observed with the concentrations of sorbitol and mannitol whereas, a positive fractional order was found in the case of inositol concentration. An inverse fractional order was observed with perchloric acid in oxidation of three substrates. Arrhenius parameters were calculated and a plausible mechanism was proposed.

  6. Influence of the Nutrient Medium on the Recovery of Dividing Cells from Tobacco Protoplasts 12

    PubMed Central

    Uchimiya, Hirofumi; Murashige, Toshio

    1976-01-01

    Systematic tests resulted in a nutrient solution containing the following, in milligrams per liter, for the culture of protoplasts isolated from Nicotiana tabacum L. callus cells: Murashige and Skoog salts (T. Murashige and F. Skoog, 1962. Physiol. Plant. 15: 473-497); sucrose, 15,000; mannitol, 110,000; α-naphthaleneacetic acid, 0.6; kinetin, 0-0.1; thiamine·HCl, 10; pyridoxine·HCl, 10; nicotinic acid, 5; myo-inositol, 100; and glycine, 2. In this medium, regeneration of cell wall has been observed in 85% and resumption of cell division among 35% of the protoplast isolates. PMID:16659496

  7. Osmoregulated taurine transport in H4IIE hepatoma cells and perfused rat liver.

    PubMed Central

    Warskulat, U; Wettstein, M; Häussinger, D

    1997-01-01

    The effects of aniso-osmotic exposure on taurine transport were studied in H4IIE rat hepatoma cells. Hyperosmotic (405 mosmol/l) exposure of H4IIE cells stimulated Na+-dependent taurine uptake and led to an increase in taurine transporter (TAUT) mRNA levels, whereas hypo-osmotic (205 mosmol/l) exposure diminished both taurine uptake and TAUT mRNA levels when compared with normo-osmotic (305 mosmol/l) control incubations. Taurine uptake increased 30-40-fold upon raising the ambient osmolarity from 205 to 405 mosmol/l. When H4IIE cells and perfused livers were preloaded with taurine, hypo-osmotic cell swelling led to a rapid release of taurine from the cells. The taurine efflux, but not taurine uptake, was sensitive to 4,4'-di-isothiocyanatostilbene-2,2'-disulphonic acid (DIDS), suggestive of an involvement of DIDS-sensitive channels in mediating volume-regulatory taurine efflux. Whereas in both H4IIE rat hepatoma cells and primary hepatocytes TAUT mRNA levels were strongly dependent upon ambient osmolarity, mRNAs for other osmolyte transporters, i.e. the betaine transporter BGT-1 and the Na+/myo-inositol transporter SMIT, were not detectable. In line with this, myo-inositol uptake by H4IIE hepatoma cells was low and was not stimulated by hyperosmolarity. However, despite the absence of BGT-1 mRNA, a slight osmosensitive uptake of betaine was observed, but the rate was less than 10% of that of taurine transport. This study identifies a constitutively expressed and osmosensitive TAUT in H4IIE cells and the use of taurine as a main osmolyte, whereas betaine and myo-inositol play little or no role in the osmolyte strategy in these cells. This is in contrast with rat liver macrophages, in which betaine has been shown to be a major osmolyte. PMID:9032454

  8. Structural Studies of Medicago truncatula Histidinol Phosphate Phosphatase from Inositol Monophosphatase Superfamily Reveal Details of Penultimate Step of Histidine Biosynthesis in Plants.

    PubMed

    Ruszkowski, Milosz; Dauter, Zbigniew

    2016-05-06

    The penultimate enzyme in the histidine biosynthetic pathway catalyzes dephosphorylation of l-histidinol 1-phosphate (HOLP) into l-histidinol. The recently discovered in Arabidopsis thaliana plant-type histidinol phosphate phosphatase (HPP) shares no homology with the two other HPP superfamilies known previously in prokaryotes and resembles myo-inositol monophosphatases (IMPases). In this work, identification of an HPP enzyme from a model legume, Medicago truncatula (MtHPP) was based on the highest sequence identity to A. thaliana enzyme. Biochemical assays confirmed that MtHPP was able to cleave inorganic phosphate from HOLP but not from d-myo-inositol-1-phosphate, the main substrate of IMPases. Dimers of MtHPP, determined by size exclusion chromatography, in the presence of CO2 or formaldehyde form mutual, methylene-bridged cross-links between Lys(158) and Cys(245) residues. Four high resolution crystal structures, namely complexes with HOLP (substrate), l-histidinol (product), and PO4 (3-) (by-product) as well as the structure showing the cross-linking between two MtHPP molecules, provide detailed structural information on the enzyme. Based on the crystal structures, the enzymatic reaction mechanism of IMPases is accustomed to fit the data for MtHPP. The enzymatic reaction, which requires Mg(2+) cations, is catalyzed mainly by amino acid residues from the N-terminal domain. The C-terminal domain, sharing little identity with IMPases, is responsible for the substrate specificity (i.e. allows the enzyme to distinguish between HOLP and d-myo-inositol-1-phosphate). Structural features, mainly the presence of a conserved Asp(246), allow MtHPP to bind HOLP specifically.

  9. Applicability and limitations of enzyme addition assays for the characterisation of soil organic phosphorus across a range of soil types

    NASA Astrophysics Data System (ADS)

    Jarosch, Klaus; Doolette, Ashlea; Smernik, Ronald; Frossard, Emmanuel; Bünemann, Else K.

    2014-05-01

    Solution 31P NMR spectroscopy is a powerful tool for the characterisation and quantification of organic P classes in soil. Potential limitations are due to costs, equipment accessibility and the requirement of relatively large amounts of sample. A recent alternative approach for the quantification of specific organic P classes is the use of substrate-specific phosphohydrolase enzymes which cleave the inorganic orthophosphate from the organic moiety. The released orthophosphate is detectable by colorimetry. Conclusions about the hydrolysed class of organic P can be made based on the comparison of inorganic P concentrations in enzymatically treated and untreated samples. The aim of this study was to test the applicability of enzyme addition assays for the characterisation of organic P classes on a) NaOH-EDTA extracts, b) soil:water filtrates (0.2 μm) and c) soil:water suspensions. The organic P classes in NaOH-EDTA extracts were also determined by 31P NMR spectroscopy, enabling a comparison between methods. Ten topsoil samples from four continents (five cambisols, two ferralsols, two luvisols and one lixisol) with varying total P content (83 - 1,1560 mg kg-1), pHH2O (4.2 - 8.0) and land management (grassland or cropped land) were analysed. Four different classes of organic P were determined by the enzyme addition assay: 1) monoester like-P (by an acid phosphatase known to hydrolyse simple monoesters, pyrophosphate and ATP), 2) DNA-like P (by a nuclease in combination with an acid phosphatase), 3) inositol phosphate-like P (by a phytase known to hydrolyse all monoester like-P plus myo-inositol hexakisphosphate and scyllo-inositol hexakisphosphate) and 4) enzyme stable-P (enzymatically not hydrolysed organic P forms). In the ten topsoil samples, NaOH-EDTA-extractable organic P ranged from 6 - 1,115 mg P kg-1 soil. Of this, 33 - 92 % was enzyme labile, with inositol phosphate-like P being the largest organic P class in most soils (15 - 51%), followed by monoester

  10. The Effect of Insulin Infusion on the Metabolites in Cerebral Tissues Assessed With Proton Magnetic Resonance Spectroscopy in Young Healthy Subjects With High and Low Insulin Sensitivity

    PubMed Central

    Karczewska-Kupczewska, Monika; Tarasów, Eugeniusz; Nikołajuk, Agnieszka; Stefanowicz, Magdalena; Matulewicz, Natalia; Otziomek, Elżbieta; Górska, Maria; Strączkowski, Marek; Kowalska, Irina

    2013-01-01

    OBJECTIVE Insulin may play important roles in brain metabolism. Proton magnetic resonance spectroscopy (1H-MRS) of the central nervous system gives information on neuronal viability, cellular energy, and membrane status. To elucidate the specific role of insulin action in the brain, we estimated neurometabolites with 1H-MRS and assessed their regulation by insulin infusion and their relationship with insulin sensitivity. RESEARCH DESIGN AND METHODS We studied 16 healthy young men. 1H-MRS was performed at baseline and after 240 min of euglycemic-hyperinsulinemic clamp. Voxels were positioned in the left frontal lobe, left temporal lobe, and left thalamus. The ratios of N-acetylaspartate (NAA), choline-containing compounds (Cho), myo-inositol, and glutamate/glutamine/γ-aminobutyric acid complex (Glx) to creatine (Cr) and nonsuppressed water signal were determined. The participants were divided into subgroups of high (high IS) and low (low IS) insulin sensitivity. RESULTS Baseline neurometabolic substrates were not different between the groups. Insulin infusion resulted in an increase in frontal NAA/Cr and NAA/H2O and frontal and temporal Glx/Cr and Glx/H2O and a decrease in frontal Cho/Cr and temporal Cho/H2O and myo-inositol/H2O (all P < 0.05, except temporal Glx/H2O, P = 0.054, NS) in the high-IS, but not in the low-IS, group. Insulin sensitivity correlated positively with frontal NAA/Cr and NAA/H2O and temporal Glx/H2O and negatively with temporal myo-inositol/Cr and myo-inositol/H2O assessed during the second 1H-MRS (all P < 0.05). CONCLUSIONS Insulin might influence cerebral metabolites, and this action is impaired in subjects with low whole-body insulin sensitivity. Thus, our results provide a potential link between insulin resistance and altered metabolism of the central nervous system. PMID:23596182

  11. Pea fiber and wheat bran fiber show distinct metabolic profiles in rats as investigated by a 1H NMR-based metabolomic approach.

    PubMed

    Liu, Guangmang; Xiao, Liang; Fang, Tingting; Cai, Yimin; Jia, Gang; Zhao, Hua; Wang, Jing; Chen, Xiaoling; Wu, Caimei

    2014-01-01

    This study aimed to examine the effect of pea fiber (PF) and wheat bran fiber (WF) supplementation in rat metabolism. Rats were assigned randomly to one of three dietary groups and were given a basal diet containing 15% PF, 15% WF, or no supplemental fiber. Urine and plasma samples were analyzed by NMR-based metabolomics. PF significantly increased the plasma levels of 3-hydroxybutyrate, and myo-inositol as well as the urine levels of alanine, hydroxyphenylacetate, phenylacetyglycine, and α-ketoglutarate. However, PF significantly decreased the plasma levels of isoleucine, leucine, lactate, and pyruvate as well as the urine levels of allantoin, bile acids, and trigonelline. WF significantly increased the plasma levels of acetone, isobutyrate, lactate, myo-inositol, and lipids as well as the urine levels of alanine, lactate, dimethylglycine, N-methylniconamide, and α-ketoglutarate. However, WF significantly decreased the plasma levels of amino acids, and glucose as well as the urine levels of acetate, allantoin, citrate, creatine, hippurate, hydroxyphenylacetate, and trigonelline. Results suggest that PF and WF exposure can promote antioxidant activity and can exhibit common systemic metabolic changes, including lipid metabolism, energy metabolism, glycogenolysis and glycolysis metabolism, protein biosynthesis, and gut microbiota metabolism. PF can also decrease bile acid metabolism. These findings indicate that different fiber diet may cause differences in the biofluid profile in rats.

  12. Mass-based metabolomic analysis of soybean sprouts during germination.

    PubMed

    Gu, Eun-Ji; Kim, Dong Wook; Jang, Gwang-Ju; Song, Seong Hwa; Lee, Jae-In; Lee, Sang Bong; Kim, Bo-Min; Cho, Yeongrae; Lee, Hyeon-Jeong; Kim, Hyun-Jin

    2017-02-15

    We investigated the metabolite profile of soybean sprouts at 0, 1, 2, 3, and 4days after germination using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-MS (LC-MS) to understand the relationship between germination and nutritional quality. Data were analyzed by partial least squares-discriminant analysis (PLS-DA), and sprout samples were separated successfully using their PLS-DA scores. Fifty-eight metabolites, including macromolecular derivatives related to energy production, amino acids, myo-inositol metabolites, phytosterols, antioxidants, isoflavones, and soyasaponins, contributed to the separation. Amino acids, myo-inositol metabolites, isoflavone aglycones, B soyasaponins, antioxidants, and phytosterols, associated with health benefits and/or taste quality, increased with germination time while isoflavone glycosides and DDMP soyasaponins decreased. Based on these metabolites, the metabolomic pathway associated with energy production in soybean sprouts is suggested. Our data suggest that sprouting is a useful processing step to improve soybean nutritional quality, and metabolomic analysis is useful in understanding nutritional change during sprouting.

  13. Mutations in the Arabidopsis homolog of LST8/GβL, a partner of the target of Rapamycin kinase, impair plant growth, flowering, and metabolic adaptation to long days.

    PubMed

    Moreau, Manon; Azzopardi, Marianne; Clément, Gilles; Dobrenel, Thomas; Marchive, Chloé; Renne, Charlotte; Martin-Magniette, Marie-Laure; Taconnat, Ludivine; Renou, Jean-Pierre; Robaglia, Christophe; Meyer, Christian

    2012-02-01

    The conserved Target of Rapamycin (TOR) kinase forms high molecular mass complexes and is a major regulator of cellular adaptations to environmental cues. The Lethal with Sec Thirteen 8/G protein β subunit-like (LST8/GβL) protein is a member of the TOR complexes, and two putative LST8 genes are present in Arabidopsis thaliana, of which only one (LST8-1) is significantly expressed. The Arabidopsis LST8-1 protein is able to complement yeast lst8 mutations and interacts with the TOR kinase. Mutations in the LST8-1 gene resulted in reduced vegetative growth and apical dominance with abnormal development of flowers. Mutant plants were also highly sensitive to long days and accumulated, like TOR RNA interference lines, higher amounts of starch and amino acids, including proline and glutamine, while showing reduced concentrations of inositol and raffinose. Accordingly, transcriptomic and enzymatic analyses revealed a higher expression of genes involved in nitrate assimilation when lst8-1 mutants were shifted to long days. The transcriptome of lst8-1 mutants in long days was found to share similarities with that of a myo-inositol 1 phosphate synthase mutant that is also sensitive to the extension of the light period. It thus appears that the LST8-1 protein has an important role in regulating amino acid accumulation and the synthesis of myo-inositol and raffinose during plant adaptation to long days.

  14. Crystal structures of Bacillus alkaline phytase in complex with divalent metal ions and inositol hexasulfate.

    PubMed

    Zeng, Yi-Fang; Ko, Tzu-Ping; Lai, Hui-Lin; Cheng, Ya-Shan; Wu, Tzu-Hui; Ma, Yanhe; Chen, Chun-Chi; Yang, Chii-Shen; Cheng, Kuo-Joan; Huang, Chun-Hsiang; Guo, Rey-Ting; Liu, Je-Ruei

    2011-06-03

    Alkaline phytases from Bacillus species, which hydrolyze phytate to less phosphorylated myo-inositols and inorganic phosphate, have great potential as additives to animal feed. The thermostability and neutral optimum pH of Bacillus phytase are attributed largely to the presence of calcium ions. Nonetheless, no report has demonstrated directly how the metal ions coordinate phytase and its substrate to facilitate the catalytic reaction. In this study, the interactions between a phytate analog (myo-inositol hexasulfate) and divalent metal ions in Bacillus subtilis phytase were revealed by the crystal structure at 1.25 Å resolution. We found all, except the first, sulfates on the substrate analog have direct or indirect interactions with amino acid residues in the enzyme active site. The structures also unraveled two active site-associated metal ions that were not explored in earlier studies. Significantly, one metal ion could be crucial to substrate binding. In addition, binding of the fourth sulfate of the substrate analog to the active site appears to be stronger than that of the others. These results indicate that alkaline phytase starts by cleaving the fourth phosphate, instead of the third or the sixth that were proposed earlier. Our high-resolution, structural representation of Bacillus phytase in complex with a substrate analog and divalent metal ions provides new insight into the catalytic mechanism of alkaline phytases in general.

  15. Pyrophosphate levels strongly influence ascorbate and starch content in tomato fruit

    PubMed Central

    Osorio, Sonia; Nunes-Nesi, Adriano; Stratmann, Marina; Fernie, Alisdair R.

    2013-01-01

    Ascorbate (vitamin C) deficiency leads to low immunity, scurvy, and other human diseases and is therefore a global health problem. Given that plants are major ascorbate sources for humans, biofortification of this vitamin in our foodstuffs is of considerable importance. Ascorbate is synthetized by a number of alternative pathways: (i) from the glycolytic intermediates D-glucose-6P (the key intermediates are GDP-D-mannose and L-galactose), (ii) from the breakdown of the cell wall polymer pectin which uses the methyl ester of D-galacturonic acid as precursor, and (iii) from myo-inositol as precursor via myo-inositol oxygenase. We report here the engineering of fruit-specific overexpression of a bacterial pyrophosphatase, which hydrolyzes the inorganic pyrophosphate (PPi) to orthophosphate (Pi). This strategy resulted in increased vitamin C levels up to 2.5-fold in ripe fruit as well as increasing in the major sugars, sucrose, and glucose, yet decreasing the level of starch. When considered together, these finding indicate an intimate linkage between ascorbate and sugar biosynthesis in plants. Moreover, the combined data reveal the importance of PPi metabolism in tomato fruit metabolism and development. PMID:23950759

  16. Drug-likeness of Phytic Acid and Its Analogues.

    PubMed

    Joy, Amitha; Balaji, S

    2015-01-01

    Inositol hexakisphosphate is known to be the phosphorous reserve in plants particularly in the seeds. Though it has been known for its antinutrient properties for many years, recent research shed light to reveal it as a novel anticancer agent. Hence the present study investigates the drug-likeness of phytic acid and its analogues through bioinformatics methods. Two potential cancer drug targets such as mitogen activated kinase and inositol 1,4,5-triphosphate receptor are included in the study. Out of 50 selected analogues of phytic acid, 42 structures interact well with the chosen drug targets. The best interacting structures are 1-diphosinositol pentakisphosphate and 2,3,4,5,6-pentaphosphonooxycyclohexyl dihydrogen phosphate. For both of these structures, the negative binding energy obtained was -49.5 KJ/mol; this affirms the stability of the complex. ADME properties are also predicted to assess the drug-like properties of the compounds. The structure activity relationship model is generated for 12 compounds with experimental IC50 values.

  17. Overexpression of a Gene Involved in Phytic Acid Biosynthesis Substantially Increases Phytic Acid and Total Phosphorus in Rice Seeds.

    PubMed

    Tagashira, Yusuke; Shimizu, Tomoe; Miyamoto, Masanobu; Nishida, Sho; Yoshida, Kaoru T

    2015-04-24

    The manipulation of seed phosphorus is important for seedling growth and environmental P sustainability in agriculture. The mechanism of regulating P content in seed, however, is poorly understood. To study regulation of total P, we focused on phytic acid (inositol hexakisphosphate; InsP₆) biosynthesis-related genes, as InsP₆ is a major storage form of P in seeds. The rice (Oryza sativa L.) low phytic acid mutant lpa1-1 has been identified as a homolog of archael 2-phosphoglycerate kinase. The homolog might act as an inositol monophosphate kinase, which catalyzes a key step in InsP₆ biosynthesis. Overexpression of the homolog in transgenic rice resulted in a significant increase in total P content in seed, due to increases in InsP₆ and inorganic phosphates. On the other hand, overexpression of genes that catalyze the first and last steps of InsP₆ biosynthesis could not increase total P levels. From the experiments using developing seeds, it is suggested that the activation of InsP₆ biosynthesis in both very early and very late periods of seed development increases the influx of P from vegetative organs into seeds. This is the first report from a study attempting to elevate the P levels of seed through a transgenic approach.

  18. Molecular pathway activation features linked with transition from normal skin to primary and metastatic melanomas in human

    PubMed Central

    Shepelin, Denis; Korzinkin, Mikhail; Vanyushina, Anna; Aliper, Alexander; Borisov, Nicolas; Vasilov, Raif; Zhukov, Nikolay; Sokov, Dmitry; Prassolov, Vladimir; Gaifullin, Nurshat; Zhavoronkov, Alex; Bhullar, Bhupinder; Buzdin, Anton

    2016-01-01

    Melanoma is the most aggressive and dangerous type of skin cancer, but its molecular mechanisms remain largely unclear. For transcriptomic data of 478 primary and metastatic melanoma, nevi and normal skin samples, we performed high-throughput analysis of intracellular molecular networks including 592 signaling and metabolic pathways. We showed that at the molecular pathway level, the formation of nevi largely resembles transition from normal skin to primary melanoma. Using a combination of bioinformatic machine learning algorithms, we identified 44 characteristic signaling and metabolic pathways connected with the formation of nevi, development of primary melanoma, and its metastases. We created a model describing formation and progression of melanoma at the level of molecular pathway activation. We discovered six novel associations between activation of metabolic molecular pathways and progression of melanoma: for allopregnanolone biosynthesis, L-carnitine biosynthesis, zymosterol biosynthesis (inhibited in melanoma), fructose 2, 6-bisphosphate synthesis and dephosphorylation, resolvin D biosynthesis (activated in melanoma), D-myo-inositol hexakisphosphate biosynthesis (activated in primary, inhibited in metastatic melanoma). Finally, we discovered fourteen tightly coordinated functional clusters of molecular pathways. This study helps to decode molecular mechanisms underlying the development of melanoma. PMID:26624979

  19. Detection of contaminating enzymatic activity in plant-derived recombinant biotechnology products.

    PubMed

    Brinson, Robert G; Giulian, Gary G; Kelman, Zvi; Marino, John P

    2014-12-02

    Residual impurities in recombinantly produced protein biologics, such as host cell proteins (HCP), can potentially cause unwanted toxic or immunogenic responses in patients. Additionally, undetected impurities found in recombinant proteins used in cell culture may adversely impact basic research and biotechnology applications. Currently, the enzyme-linked immunosorbent assay (ELISA) is the standard for detection of residual HCP contamination in recombinantly produced biologics. Alternatively, two-dimensional liquid chromatography coupled to mass spectrometry is being developed as a tool for assessing this critical quality attribute. Both of these methods rely on the direct detection of HCPs and some previous knowledge of the contaminant. For contaminating enzymes, the mass level of the impurity may fall below the threshold of detection of these methods and underestimate the true impact. To address this point, here we demonstrate facile detection and characterization of contaminating phytase activity in rice-derived recombinant human serum albumin (rHSA) using a sensitive, label-free nuclear magnetic resonance (NMR) spectroscopy assay. We observed varying degrees of phytase contamination in biotechnology-grade rHSA from various manufacturers by monitoring the degradation of adenosine-5'-triphosphate and myo-inositol-1,2,3,4,5,6-hexakisphosphate by (31)P NMR. The observed lot-to-lot variability may result in irreproducible cell culture results and should be evaluated as a possible critical quality attribute in plant-derived biotherapeutics.

  20. Molecular pathway activation features linked with transition from normal skin to primary and metastatic melanomas in human.

    PubMed

    Shepelin, Denis; Korzinkin, Mikhail; Vanyushina, Anna; Aliper, Alexander; Borisov, Nicolas; Vasilov, Raif; Zhukov, Nikolay; Sokov, Dmitry; Prassolov, Vladimir; Gaifullin, Nurshat; Zhavoronkov, Alex; Bhullar, Bhupinder; Buzdin, Anton

    2016-01-05

    Melanoma is the most aggressive and dangerous type of skin cancer, but its molecular mechanisms remain largely unclear. For transcriptomic data of 478 primary and metastatic melanoma, nevi and normal skin samples, we performed high-throughput analysis of intracellular molecular networks including 592 signaling and metabolic pathways. We showed that at the molecular pathway level, the formation of nevi largely resembles transition from normal skin to primary melanoma. Using a combination of bioinformatic machine learning algorithms, we identified 44 characteristic signaling and metabolic pathways connected with the formation of nevi, development of primary melanoma, and its metastases. We created a model describing formation and progression of melanoma at the level of molecular pathway activation. We discovered six novel associations between activation of metabolic molecular pathways and progression of melanoma: for allopregnanolone biosynthesis, L-carnitine biosynthesis, zymosterol biosynthesis (inhibited in melanoma), fructose 2, 6-bisphosphate synthesis and dephosphorylation, resolvin D biosynthesis (activated in melanoma), D-myo-inositol hexakisphosphate biosynthesis (activated in primary, inhibited in metastatic melanoma). Finally, we discovered fourteen tightly coordinated functional clusters of molecular pathways. This study helps to decode molecular mechanisms underlying the development of melanoma.

  1. Potential of Phytase-Mediated Iron Release from Cereal-Based Foods: A Quantitative View

    PubMed Central

    Nielsen, Anne V. F.; Tetens, Inge; Meyer, Anne S.

    2013-01-01

    The major part of iron present in plant foods such as cereals is largely unavailable for direct absorption in humans due to complexation with the negatively charged phosphate groups of phytate (myo-inositol (1,2,3,4,5,6)-hexakisphosphate). Human biology has not evolved an efficient mechanism to naturally release iron from iron phytate complexes. This narrative review will evaluate the quantitative significance of phytase-catalysed iron release from cereal foods. In vivo studies have shown how addition of microbially derived phytases to cereal-based foods has produced increased iron absorption via enzyme-catalysed dephosphorylation of phytate, indicating the potential of this strategy for preventing and treating iron deficiency anaemia. Despite the immense promise of this strategy and the prevalence of iron deficiency worldwide, the number of human studies elucidating the significance of phytase-mediated improvements in iron absorption and ultimately in iron status in particularly vulnerable groups is still low. A more detailed understanding of (1) the uptake mechanism for iron released from partially dephosphorylated phytate chelates, (2) the affinity of microbially derived phytases towards insoluble iron phytate complexes, and (3) the extent of phytate dephosphorylation required for iron release from inositol phosphates is warranted. Phytase-mediated iron release can improve iron absorption from plant foods. There is a need for development of innovative strategies to obtain better effects. PMID:23917170

  2. Production, purification and properties of microbial phytases.

    PubMed

    Pandey, A; Szakacs, G; Soccol, C R; Rodriguez-Leon, J A; Soccol, V T

    2001-05-01

    Phytases (myo-inositol hexakisphosphate phosphohydrolase, EC 3.1.3.8) catalyse the release of phosphate from phytate (mycoinositol hexakiphosphate). Several cereal grains, legumes and oilseeds, etc., store phosphorus as phytate. Environmental pollution due to the high-phosphate manure, resulting in the accumulation of P at various locations has raised serious concerns. Phytases appear of significant value in effectively controlling P pollution. They can be produced from a host of sources including plants, animals and micro-organisms. Microbial sources, however, are promising for their commercial exploitations. Strains of Aspergillus sp., chiefly A. ficuum and A. niger have most commonly been employed for industrial purposes. Phytases are considered as a monomeric protein, generally possessing a molecular weight between 40 and 100 kDa. They show broad substrate specificity and have generally pH and temperature optima around 4.5-6.0 and 45-60 degrees C. The crystal structure of phytase has been determined at 2.5 A resolution. Immobilization of phytase has been found to enhance its thermostability. This article reviews recent trends on the production, purification and properties of microbial phytases.

  3. Evaluation of phosphorus characterization in broiler ileal digesta, manure, and litter samples: (31)P-NMR vs. HPLC.

    PubMed

    Leytem, A B; Kwanyuen, P; Plumstead, P W; Maguire, R O; Brake, J

    2008-01-01

    Using 31-phosphorus nuclear magnetic resonance spectroscopy ((31)P-NMR) to characterize phosphorus (P) in animal manures and litter has become a popular technique in the area of nutrient management. To date, there has been no published work evaluating P quantification in manure/litter samples with (31)P-NMR compared to other accepted methods such as high performance liquid chromatography (HPLC). To evaluate the use of (31)P-NMR to quantify myo-inositol hexakisphosphate (phytate) in ileal digesta, manure, and litter from broilers, we compared results obtained from both (31)P-NMR and a more traditional HPLC method. The quantification of phytate in all samples was very consistent between the two methods, with linear regressions having slopes ranging from 0.94 to 1.07 and r(2) values of 0.84 to 0.98. We compared the concentration of total monoester P determined with (31)P-NMR with the total inositol P content determined with HPLC and found a strong linear relationship between the two measurements having slopes ranging from 0.91 to 1.08 and r(2) values of 0.73 to 0.95. This suggests that (31)P-NMR is a very reliable method for quantifying P compounds in manure/litter samples.

  4. Validation of an LC-MS bioanalytical method for quantification of phytate levels in rat, dog and human plasma.

    PubMed

    Tur, Fernando; Tur, Eva; Lentheric, Irene; Mendoza, Paula; Encabo, Maximo; Isern, Bernat; Grases, Felix; Maraschiello, Ciriaco; Perelló, Joan

    2013-06-01

    Myo-inositol hexakisphosphate (phytate, IP6) is a naturally occuring compound whose determination in biological matrices is chanllenging. Several benefitial properties have been attributed to IP6 in parallel with the development of suitable analytical methodologies for its analytical determination in urine and some tissues. However, there is a lack of appropriate tools for its determination in plasma samples. In this paper, a direct, sensitive and selective bioanalytical method for the determination of IP6 based on LC-MS is presented. It is the first method published to quantify IP6 in plasma matrices directly through its molecular weight, being consequently a highly specific methodology. The method has been validated in rat, dog and human plasma, according to the acceptance criteria laid down in the FDA guidance Bioanalytical Method Validation. Accuracy and precision were not greater than 15% at medium and high concentrations and not greater than 20% at the LLOQ concentration. The mean absolute recovery obtained ranged from 78.74 to 102.44%, 62.10 to 87.21% and 61.61 to 86.99% for rat, dog and human plasma respectively. The LLOQ was 500ngmL(-1) due to the presence of endogenous IP6 in blank plasma samples and the limit of detection was within the range 30-80ngmL(-1).

  5. Inositol phosphates in the environment.

    PubMed Central

    Turner, Benjamin L; Papházy, Michael J; Haygarth, Philip M; McKelvie, Ian D

    2002-01-01

    The inositol phosphates are a group of organic phosphorus compounds found widely in the natural environment, but that represent the greatest gap in our understanding of the global phosphorus cycle. They exist as inositols in various states of phosphorylation (bound to between one and six phosphate groups) and isomeric forms (e.g. myo, D-chiro, scyllo, neo), although myo-inositol hexakisphosphate is by far the most prevalent form in nature. In terrestrial environments, inositol phosphates are principally derived from plants and accumulate in soils to become the dominant class of organic phosphorus compounds. Inositol phosphates are also present in large amounts in aquatic environments, where they may contribute to eutrophication. Despite the prevalence of inositol phosphates in the environment, their cycling, mobility and bioavailability are poorly understood. This is largely related to analytical difficulties associated with the extraction, separation and detection of inositol phosphates in environmental samples. This review summarizes the current knowledge of inositol phosphates in the environment and the analytical techniques currently available for their detection in environmental samples. Recent advances in technology, such as the development of suitable chromatographic and capillary electrophoresis separation techniques, should help to elucidate some of the more pertinent questions regarding inositol phosphates in the natural environment. PMID:12028785

  6. Purification and characterisation of an extracellular phytase from Aspergillus niger 11T53A9

    PubMed Central

    Greiner, Ralf; da Silva, Lucineia Gomes; Couri, Sonia

    2009-01-01

    An extracellular phytase from Aspergillus niger 11T53A9 was purified about 51-fold to apparent homogeneity with a recovery of 20.3% referred to the phytase activity in the crude extract. Purification was achieved by ammonium sulphate precipitation, ion chromataography and gel filtration. The purified enzyme behaved as a monomeric protein with a molecular mass of about 85 kDa and exhibited maximal phytate-degrading activity at pH 5.0. Optimum temperature for the degradation of phytate was 55°C. The kinetic parameters for the hydrolysis of sodium phytate were determined to be KM = 54 µmol l-1 and kcat = 190 sec-1 at pH 5.0 and 37°C. The purified enzyme was rather specific for phytate dephosphorylation. It was shown that the phytase preferably dephosphorylates myo-inositol hexakisphosphate in a stereospecific way by sequential removal of phosphate groups via D-Ins(1,2,4,5,6)P5, D-Ins(1,2,5,6)P4, D-Ins(1,2,6)P3, D-Ins(1,2)P2 to finally Ins(2)P. PMID:24031427

  7. Phytic acid as a potential treatment for Alzheimer's pathology: evidence from animal and in vitro models

    PubMed Central

    Anekonda, Thimmappa S.; Wadsworth, Teri L.; Sabin, Robert; Frahler, Kate; Harris, Christopher; Petriko, Babett; Ralle, Martina; Woltjer, Randy; Quinn, Joseph F.

    2010-01-01

    Alzheimer’s disease (AD) causes progressive age-dependent cortical and hippocampal dysfunctions leading to abnormal intellectual capacity and memory. We propose a novel protective treatment for AD pathology with phytic acid (inositol hexakisphosphate), a phytochemical found in food grains and a key signaling molecule in mammalian cells. We evaluated the protective and beneficial effects of phytic acid against amyloid beta pathology in MC65 cells and the Tg2576 mouse model. In MC65 cells, 48–72-hour treatment with phytic acid provided complete protection against amyloid precursor protein-C-terminal fragment-induced cytotoxicity by attenuating levels of increased intracellular calcium, hydrogen peroxide, superoxide, beta amyloid oligomers, and moderately up-regulated the expression of autophagy (beclin-1) protein. In a tolerance paradigm, wild type mice were treated with 2% phytic acid in drinking water for 70 days. Phytic acid was well tolerated. Ceruloplasmin activity, brain copper and iron levels and brain superoxide dismutase and ATP levels were unaffected by the treatment. There was a significant increase in brain levels of cytochrome oxidase and a decrease in lipid peroxidation with phytic acid administration. In a treatment paradigm, 12-month old Tg2576 and wild type mice were treated with 2% phytic acid or vehicle for 6 months. Brain levels of copper, iron, and zinc were unaffected. The effects of phytic acid were modest on the expression of APP trafficking-associated protein AP180, autophagy-associated proteins (beclin-1, LC3B), sirtuin 1, the ratio of phosphorylated AMP-activated protein kinase (PAMPK) to AMPK, soluble Aβ1-40, and insoluble Aβ1-42. These results suggest that phytic acid may provide a viable treatment option for AD. PMID:20930278

  8. Phytic acid as a potential treatment for alzheimer's pathology: evidence from animal and in vitro models.

    PubMed

    Anekonda, Thimmappa S; Wadsworth, Teri L; Sabin, Robert; Frahler, Kate; Harris, Christopher; Petriko, Babett; Ralle, Martina; Woltjer, Randy; Quinn, Joseph F

    2011-01-01

    Alzheimer's disease (AD) causes progressive, age-dependent cortical and hippocampal dysfunction leading to abnormal intellectual capacity and memory. We propose a novel protective treatment for AD pathology with phytic acid (inositol hexakisphosphate), a phytochemical found in food grains and a key signaling molecule in mammalian cells. We evaluated the protective and beneficial effects of phytic acid against amyloid-β (Aβ) pathology in MC65 cells and the Tg2576 mouse model. In MC65 cells, 48-72-hour treatment with phytic acid provided complete protection against amyloid precursor protein-C-terminal fragment-induced cytotoxicity by attenuating levels of increased intracellular calcium, hydrogen peroxide, superoxide, Aβ oligomers, and moderately upregulated the expression of autophagy (beclin-1) protein. In a tolerance paradigm, wild type mice were treated with 2% phytic acid in drinking water for 70 days. Phytic acid was well tolerated. Ceruloplasmin activity, brain copper and iron levels, and brain superoxide dismutase and ATP levels were unaffected by the treatment. There was a significant increase in brain levels of cytochrome oxidase and a decrease in lipid peroxidation with phytic acid administration. In a treatment paradigm, 12-month old Tg2576 and wild type mice were treated with 2% phytic acid or vehicle for 6 months. Brain levels of copper, iron, and zinc were unaffected. The effects of phytic acid were modest on the expression of AβPP trafficking-associated protein AP180, autophagy-associated proteins (beclin-1, LC3B), sirtuin 1, the ratio of phosphorylated AMP-activated protein kinase (PAMPK) to AMPK, soluble Aβ1-40, and insoluble Aβ1-42. These results suggest that phytic acid may provide a viable treatment option for AD.

  9. Inositol prevents folate-resistant neural tube defects in the mouse.

    PubMed

    Greene, N D; Copp, A J

    1997-01-01

    Clinical trials demonstrate that up to 70% of neural tube defects (NTDs) can be prevented by folic acid supplementation in early pregnancy, whereas the remaining NTDs are resistant to folate. Here, we show that a second vitamin, myo-inositol, is capable of significantly reducing the incidence of spinal NTDs in curly tail mice, a genetic model of folate-resistant NTDs. Inositol increases flux through the inositol/lipid cycle, stimulating protein kinase C activity and upregulating expression of retinoic acid receptor beta, specifically in the caudal portion of the embryonic hindgut. This reduces the delay in closure of the posterior neuropore, the embryonic defect that is known to lead directly to spina bifida in curly tail embryos. Our findings reveal a molecular pathway of NTD prevention and suggest the possible efficacy of combined treatment with folate and inositol in overcoming the majority of human NTDs.

  10. Gravity-induced asymmetric distribution of a plant growth hormone

    NASA Technical Reports Server (NTRS)

    Bandurski, R. S.; Schulze, A.; Momonoki, Y.

    1984-01-01

    Dolk (1936) demonstrated that gravistimulation induced an asymmetric distribution of auxin in a horizontally-placed shoot. An attempt is made to determine where and how that asymmetry arises, and to demonstrate that the endogenous auxin, indole-3-acetic acid, becomes asymmetrically distributed in the cortical cells of the Zea mays mesocotyl during 3 min of geostimulation. Further, indole-3-acetic acid derived by hydrolysis of an applied transport form of the hormone, indole-3-acetyl-myo-inositol, becomes asymmetrically distributed within 15 min of geostimulus time. From these and prior data is developed a working theory that the gravitational stimulus induces a selective leakage, or secretion, of the hormone from the vascular tissue to the cortical cells of the mesocotyl.

  11. Bacillus phytases: Current status and future prospects

    PubMed Central

    Borgi, Mohamed Ali; Boudebbouze, Samira; Mkaouar, Héla; Maguin, Emmanuelle; Rhimi, Moez

    2015-01-01

    Abstract Phytases catalyze the hydrolysis of phytic acid in a stepwise manner to lower inositol phosphates, myo-inositol (having important role in metabolism and signal transduction pathways), and inorganic phosphate. These enzymes have been widely used in animal feed in order to improve phosphorus nutrition and to decrease pollution in animal waste. Compared to previously described phytases, the phytase (PhyL) from Bacillus licheniformis ATCC 14580 has attractive biochemical properties which can increase the profitability of several biotechnological procedures (animal nutrition, humain health…etc). Due to its amino acid sequence with critical substitutions, the PhyL could be a model to enhance other phytases features, in terms of thermal stability and high activity. Otherwise, an engineered PhyL, with low pH optimum, will represent a challenge within the class of β- propeller phytases. PMID:25946551

  12. Peripheral neuropathy: pathogenic mechanisms and alternative therapies.

    PubMed

    Head, Kathleen A

    2006-12-01

    Peripheral neuropathy (PN), associated with diabetes, neurotoxic chemotherapy, human immunodeficiency virus (HIV)/antiretroviral drugs, alcoholism, nutrient deficiencies, heavy metal toxicity, and other etiologies, results in significant morbidity. Conventional pain medications primarily mask symptoms and have significant side effects and addiction profiles. However, a widening body of research indicates alternative medicine may offer significant benefit to this patient population. Alpha-lipoic acid, acetyl-L-carnitine, benfotiamine, methylcobalamin, and topical capsaicin are among the most well-researched alternative options for the treatment of PN. Other potential nutrient or botanical therapies include vitamin E, glutathione, folate, pyridoxine, biotin, myo-inositol, omega-3 and -6 fatty acids, L-arginine, L-glutamine, taurine, N-acetylcysteine, zinc, magnesium, chromium, and St. John's wort. In the realm of physical medicine, acupuncture, magnetic therapy, and yoga have been found to provide benefit. New cutting-edge conventional therapies, including dual-action peptides, may also hold promise.

  13. Computational based functional analysis of Bacillus phytases.

    PubMed

    Verma, Anukriti; Singh, Vinay Kumar; Gaur, Smriti

    2016-02-01

    Phytase is an enzyme which catalyzes the total hydrolysis of phytate to less phosphorylated myo-inositol derivatives and inorganic phosphate and digests the undigestable phytate part present in seeds and grains and therefore provides digestible phosphorus, calcium and other mineral nutrients. Phytases are frequently added to the feed of monogastric animals so that bioavailability of phytic acid-bound phosphate increases, ultimately enhancing the nutritional value of diets. The Bacillus phytase is very suitable to be used in animal feed because of its optimum pH with excellent thermal stability. Present study is aimed to perform an in silico comparative characterization and functional analysis of phytases from Bacillus amyloliquefaciens to explore physico-chemical properties using various bio-computational tools. All proteins are acidic and thermostable and can be used as suitable candidates in the feed industry.

  14. Bacillus phytases: Current status and future prospects.

    PubMed

    Borgi, Mohamed Ali; Boudebbouze, Samira; Mkaouar, Héla; Maguin, Emmanuelle; Rhimi, Moez

    2015-01-01

    Phytases catalyze the hydrolysis of phytic acid in a stepwise manner to lower inositol phosphates, myo-inositol (having important role in metabolism and signal transduction pathways), and inorganic phosphate. These enzymes have been widely used in animal feed in order to improve phosphorus nutrition and to decrease pollution in animal waste. Compared to previously described phytases, the phytase (PhyL) from Bacillus licheniformis ATCC 14580 has attractive biochemical properties which can increase the profitability of several biotechnological procedures (animal nutrition, humain health…etc). Due to its amino acid sequence with critical substitutions, the PhyL could be a model to enhance other phytases features, in terms of thermal stability and high activity. Otherwise, an engineered PhyL, with low pH optimum, will represent a challenge within the class of β- propeller phytases.

  15. TISSUE METABOLOMICS OF HEPATOCELLULAR CARCINOMA: TUMOR ENERGY METABOLISM AND THE ROLE OF TRANSCRIPTOMIC CLASSIFICATION

    PubMed Central

    Beyoğlu, Diren; Imbeaud, Sandrine; Maurhofer, Olivier; Bioulac-Sage, Paulette; Zucman-Rossi, Jessica; Dufour, Jean-François; Idle, Jeffrey R.

    2013-01-01

    Hepatocellular carcinoma (HCC) is one of the commonest causes of death from cancer. A plethora of metabolomic investigations of HCC have yielded molecules in biofluids that are both up- and downregulated but no real consensus has emerged regarding exploitable biomarkers for early detection of HCC. We report here a different approach, a combined transcriptomics and metabolomics study of energy metabolism in HCC. A panel of 31 pairs of HCC tumors and corresponding non-tumor liver tissues from the same patients was investigated by gas chromatography-mass spectrometry (GCMS) based metabolomics. HCC was characterized by approximately two-fold depletion of glucose, glycerol 3- and 2-phosphate, malate, alanine, myo-inositol, and linoleic acid. Data are consistent with a metabolic remodeling involving a four-fold increase in glycolysis over mitochondrial oxidative phosphorylation. A second panel of 59 HCC that had been typed by transcriptomics and classified in G1 to G6 subgroups was also subjected to GCMS tissue metabolomics. No differences in glucose, lactate, alanine, glycerol 3-phosphate, malate, myo-inositol or stearic acid tissue concentrations were found, suggesting that the Wnt/β-catenin pathway activated by CTNNB1 mutation in subgroups G5 and G6 did not exhibit specific metabolic remodeling. However, subgroup G1 had markedly reduced tissue concentrations of 1-stearoylglycerol, 1-palmitoylglycerol, and palmitic acid, suggesting that the high serum α-fetoprotein phenotype of G1, associated with the known overexpression of lipid catabolic enzymes, could be detected through metabolomics as increased lipid catabolism. Conclusion Tissue metabolomics yielded precise biochemical information regarding HCC tumor metabolic remodeling from mitochondrial oxidation to aerobic glycolysis and the impact of molecular subtypes on this process. PMID:23463346

  16. Pasteurella caballi, a new species from equine clinical specimens.

    PubMed Central

    Schlater, L K; Brenner, D J; Steigerwalt, A G; Moss, C W; Lambert, M A; Packer, R A

    1989-01-01

    The name Pasteurella caballi is proposed for a group of organisms represented by 29 strains isolated from respiratory and other infections in horses. P. caballi strains are gram-negative, oxidase-positive, nonmotile, fermentative rods with the key characteristics of the genus Pasteurella. These strains differed from other Pasteurella species in that all were aerogenic and catalase negative, and some strains produced acid from myo-inositol and L-rhamnose. The levels of DNA relatedness of 28 P. caballi strains with labeled DNA from the proposed type strain averaged 91 and 85% (hydroxyapatite method at 55 and 70 degrees C). P. caballi was 13 to 53% related to strains representing 22 other species of the family Pasteurellaceae. The guanine-plus-cytosine content of the DNA of four strains was 41 to 42 mol%. The type strain is 83851 (=ATCC 49197). PMID:2584369

  17. [Application of phytases as functional ingredient in foods].

    PubMed

    Frontela, Carmen; Ros, Gaspar; Martínez, Carmen

    2008-09-01

    Various food processing and preparation methods result in a reduction in the phytate content of cereals and legumes. However, in general during these processes, phytate is not fully hydrolysed. To alleviate the aforementioned problems in the production of animal feeds, exogenous phytases (myo-inositol hexaphosphate phosphohydrolases) have been widely used. There is great potential, therefore, to use this class of enzymes in the processing and manufacturing of food for human consumption given the capacity to improve mineral bioavailability. This is seen as a way to reduce the risk of mineral deficiency in vulnerable groups including; childbearing women; strict vegetarians; babies consuming soy-based infant formulas; and the inhabitants of developing countries. There is, however, growing evidence to demonstrate the beneficial role played by phytic acid in all human organisms.

  18. Pharmacological Modulation of Lung Carcinogenesis in Smokers: Preclinical and Clinical Evidence

    PubMed Central

    De Flora, Silvio; Ganchev, Gancho; Iltcheva, Marietta; La Maestra, Sebastiano; Micale, Rosanna T.; Steele, Vernon E.; Balansky, Roumen

    2016-01-01

    Many drugs in common use possess pleiotropic properties that make them capable of interfering with carcinogenesis mechanisms. We discuss here the ability of pharmacological agents to mitigate the pulmonary carcinogenicity of mainstream cigarette smoke. The evaluated agents included antiinflammatory drugs (budesonide, celecoxib, aspirin, naproxen, licofelone), antidiabetic drugs (metformin, pioglitazone), antineoplastic agents (lapatinib, bexarotene, vorinostat), and other drugs and supplements (phenethyl isothiocyanate, myo-inositol, N-acetylcysteine, ascorbic acid, berry extracts). The drugs have been evaluated in mouse models mimicking interventions either in current smokers or in ex-smokers or a prenatal chemoprevention. They displayed a broad spectrum of activities by attenuating either smoke-induced preneoplastic lesions or benign tumors and/or malignant tumors. Together with epidemiological data, these findings provide useful information to predict the potential effects of pharmacological agents in smokers. PMID:26726119

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

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

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

  20. Phosphatidylinositol(4,5)bisphosphate and phosphatidylinositol(4)phosphate in plant tissues. [Pisum sativum

    SciTech Connect

    Irvine, R.F.; Letcher, A.J.; Lander, D.J. ); Dawson, A.P. ); Musgrave, A. ); Drobak, B.K. )

    1989-03-01

    Pea (Pisum sativum) leaf discs or swimming suspensions of Chlamydomonas eugametos were radiolabeled with ({sup 3}H)myo-inositol or ({sup 32}P)Pi and the lipids were extracted, deacylated, and their glycerol moieties removed. The resulting inositol trisphosphate and bisphosphate fractions were examined by periodate degradation, reduction and dephosphorylation, or by incubation with human red cell membranes. Their likely structures were identified as D-myo-inositol(1,4,5)trisphosphate and D-myo-inositol(1,4,)-bisphosphate. It is concluded that plants contain phosphatidylinositol(4)phosphate and phosphatidylinositol(4,5)bisphosphate; no other polyphosphoinositides were detected.

  1. Water Deficit Affects Primary Metabolism Differently in Two Lolium multiflorum/Festuca arundinacea Introgression Forms with a Distinct Capacity for Photosynthesis and Membrane Regeneration

    PubMed Central

    Perlikowski, Dawid; Czyżniejewski, Mariusz; Marczak, Łukasz; Augustyniak, Adam; Kosmala, Arkadiusz

    2016-01-01

    Understanding how plants respond to drought at different levels of cell metabolism is an important aspect of research on the mechanisms involved in stress tolerance. Furthermore, a dissection of drought tolerance into its crucial components by the use of plant introgression forms facilitates to analyze this trait more deeply. The important components of plant drought tolerance are the capacity for photosynthesis under drought conditions, and the ability of cellular membrane regeneration after stress cessation. Two closely related introgression forms of Lolium multiflorum/Festuca arundinacea, differing in the level of photosynthetic capacity during stress, and in the ability to regenerate their cellular membranes after stress cessation, were used as forage grass models in a primary metabolome profiling and in an evaluation of chloroplast 1,6-bisphosphate aldolase accumulation level and activity, during 11 days of water deficit, followed by 10 days of rehydration. It was revealed here that the introgression form, characterized by the ability to regenerate membranes after rehydration, contained higher amounts of proline, melibiose, galactaric acid, myo-inositol and myo-inositol-1-phosphate involved in osmoprotection and stress signaling under drought. Moreover, during the rehydration period, this form also maintained elevated accumulation levels of most the primary metabolites, analyzed here. The other introgression form, characterized by the higher capacity for photosynthesis, revealed a higher accumulation level and activity of chloroplast aldolase under drought conditions, and higher accumulation levels of most photosynthetic products during control and drought periods. The potential impact of the observed metabolic alterations on cellular membrane recovery after stress cessation, and on a photosynthetic capacity under drought conditions in grasses, are discussed. PMID:27504113

  2. In vivo two-dimensional NMR correlation spectroscopy

    NASA Astrophysics Data System (ADS)

    Kraft, Robert A.

    1999-10-01

    The poor resolution of in-vivo one- dimensional nuclear magnetic resonance spectroscopy (NMR) has limited its clinical potential. Currently, only the large singlet methyl resonances arising from N-acetyl aspartate (NAA), choline, and creatine are quantitated in a clinical setting. Other metabolites such as myo- inositol, glutamine, glutamate, lactate, and γ- amino butyric acid (GABA) are of clinical interest but quantitation is difficult due to the overlapping resonances and limited spectral resolution. To improve the spectral resolution and distinguish between overlapping resonances, a series of two- dimensional chemical shift correlation spectroscopy experiments were developed for a 1.5 Tesla clinical imaging magnet. Two-dimensional methods are attractive for in vivo spectroscopy due to their ability to unravel overlapping resonances with the second dimension, simplifying the interpretation and quantitation of low field NMR spectra. Two-dimensional experiments acquired with mix-mode line shape negate the advantages of the second dimension. For this reason, a new experiment, REVOLT, was developed to achieve absorptive mode line shape in both dimensions. Absorptive mode experiments were compared to mixed mode experiments with respect to sensitivity, resolution, and water suppression. Detailed theoretical and experimental calculations of the optimum spin lock and radio frequency power deposition were performed. Two-dimensional spectra were acquired from human bone marrow and human brain tissue. The human brain tissue spectra clearly reveal correlations among the coupled spins of NAA, glutamine, glutamate, lactate, GABA, aspartate and myo-inositol obtained from a single experiment of 23 minutes from a volume of 59 mL. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

  3. Water Deficit Affects Primary Metabolism Differently in Two Lolium multiflorum/Festuca arundinacea Introgression Forms with a Distinct Capacity for Photosynthesis and Membrane Regeneration.

    PubMed

    Perlikowski, Dawid; Czyżniejewski, Mariusz; Marczak, Łukasz; Augustyniak, Adam; Kosmala, Arkadiusz

    2016-01-01

    Understanding how plants respond to drought at different levels of cell metabolism is an important aspect of research on the mechanisms involved in stress tolerance. Furthermore, a dissection of drought tolerance into its crucial components by the use of plant introgression forms facilitates to analyze this trait more deeply. The important components of plant drought tolerance are the capacity for photosynthesis under drought conditions, and the ability of cellular membrane regeneration after stress cessation. Two closely related introgression forms of Lolium multiflorum/Festuca arundinacea, differing in the level of photosynthetic capacity during stress, and in the ability to regenerate their cellular membranes after stress cessation, were used as forage grass models in a primary metabolome profiling and in an evaluation of chloroplast 1,6-bisphosphate aldolase accumulation level and activity, during 11 days of water deficit, followed by 10 days of rehydration. It was revealed here that the introgression form, characterized by the ability to regenerate membranes after rehydration, contained higher amounts of proline, melibiose, galactaric acid, myo-inositol and myo-inositol-1-phosphate involved in osmoprotection and stress signaling under drought. Moreover, during the rehydration period, this form also maintained elevated accumulation levels of most the primary metabolites, analyzed here. The other introgression form, characterized by the higher capacity for photosynthesis, revealed a higher accumulation level and activity of chloroplast aldolase under drought conditions, and higher accumulation levels of most photosynthetic products during control and drought periods. The potential impact of the observed metabolic alterations on cellular membrane recovery after stress cessation, and on a photosynthetic capacity under drought conditions in grasses, are discussed.

  4. Thermal and refining processes, not fermentation, tend to reduce lipotropic capacity of plant-based foods.

    PubMed

    Fardet, Anthony; Martin, Jean-François; Chardigny, Jean-Michel

    2011-08-01

    Plant-based foods (PBF) are relevant and diversified sources of lipotropes, which are compounds preventing excess hepatic fat deposits. In a first study, we defined the lipotropic capacity (LC, %) of raw PBF as the means of 8 lipotrope densities (LD, mg/100 kcal), each expressed relative to that of a reference food ranking the highest considering its mean 8 LD ranks (LC(raw asparagus)=100%) (A. Fardet, J.-F. Martin and J. M. Chardigny, J. Food Comp. Anal., 2011, DOI: 10.1016/j.jfca.2011.1003.1013). We showed that vegetables appeared as the best source of lipotropes on a 100 kcal-basis compared to legumes, cereals, fruits and nuts. The main objective of this second study was to quantify the effect of processing on LD and LC of raw PBF based on lipotrope contents collected in a USDA (United State Department of Agriculture) database and the literature, i.e. betaine, choline, myo-inositol, methionine, magnesium, niacin, pantothenic acid and folate contents. Choline and betaine densities were not significantly affected by processing while methionine and lipotropic micronutrient densities were significantly decreased, especially for magnesium, pantothenate and folates. Myo-inositol density decreases were insignificant due to lower product number resulting from limited literature data. Lipotropic micronutrient densities were more affected by processing than other densities. Fermentations increased betaine (median change of +32%) and choline (+34%) densities. Canning and boiling vegetables increased choline densities (+26%). Globally, processing significantly reduced LC by ∼20%, fermentations being less drastic (median change of -5%) than refining (-33%) and thermal treatments (-16%). More specifically, canning increased LC of beetroot (536 vs 390%) and common bean (40 vs 36%) as fermentation towards LC grape (14 vs 7% for wine). Results were then mainly discussed based on percentages of lipotrope content changes on a dry-weight basis. Results of this study also showed

  5. Caffeine consumption attenuates neurochemical modifications in the hippocampus of streptozotocin-induced diabetic rats.

    PubMed

    Duarte, João M N; Carvalho, Rui A; Cunha, Rodrigo A; Gruetter, Rolf

    2009-10-01

    Type 1 diabetes can affect hippocampal function triggering cognitive impairment through unknown mechanisms. Caffeine consumption prevents hippocampal degeneration and memory dysfunction upon different insults and is also known to affect peripheral glucose metabolism. Thus we now characterized glucose transport and the neurochemical profile in the hippocampus of streptozotocin-induced diabetic rats using in vivo(1)H NMR spectroscopy and tested the effect of caffeine consumption thereupon. We found that hippocampal glucose content and transport were unaltered in diabetic rats, irrespective of caffeine consumption. However diabetic rats displayed alterations in their hippocampal neurochemical profile, which were normalized upon restoration of normoglycaemia, with the exception of myo-inositol that remained increased (36 +/- 5%, p < 0.01 compared to controls) likely reflecting osmolarity deregulation. Compared to controls, caffeine-consuming diabetic rats displayed increased hippocampal levels of myo-inositol (15 +/- 5%, p < 0.05) and taurine (23 +/- 4%, p < 0.01), supporting the ability of caffeine to control osmoregulation. Compared to controls, the hippocampus of diabetic rats displayed a reduced density of synaptic proteins syntaxin, synaptophysin and synaptosome-associated protein of 25 kDa (in average 18 +/- 1%, p < 0.05) as well increased glial fibrillary acidic protein (20 +/- 5%, p < 0.05), suggesting synaptic degeneration and astrogliosis, which were prevented by caffeine consumption. In conclusion, neurochemical alterations in the hippocampus of diabetic rats are not related to defects of glucose transport but likely reflect osmoregulatory adaptations caused by hyperglycemia. Furthermore, caffeine consumption affected this neurochemical adaptation to high glucose levels, which may contribute to its potential neuroprotective effects, namely preventing synaptic degeneration and astrogliosis.

  6. Cyclic nucleotide regulation of inositol lipid metabolism in rat cerebral cortex

    SciTech Connect

    Nicchitta, C.V.; Williamson, J.R.

    1986-05-01

    The authors have investigated the effects of compounds known to elevate cAMP levels and/or activate the cAMP dependent protein kinase on resting and stimulated inositol lipid metabolism in rat cortical slices and synaptosomes. In (/sup 3/H)-myo-inositol-labeled brain slices, carbamylcholine-stimulated accumulation of (/sup 3/H)-myo-inositol 1-phosphate (IP/sub 1/) was decreased 50% by forskolin (150..mu..M) isobutylmethylxantihine (IBMX) (1mM), 8-bromo cAMP (5mM) or 8-(4-chlorophenylthio) cAMP (5mM). In studies with synaptosomes, the incorporation of (/sup 32/Pi) into phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP), phosphatidylinositol 4,5-bisphosphate (PIP/sub 2/) and phosphatidic acid (PA) was also reduced in the presence of forskolin or the cAMP phosphodiesterase inhibitors IBMX and RO20-1724 (+/-)-4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone. In the presence of maximally effective concentrations of these agents, steady state PIP levels were reduced by 50% and PIP/sub 2/ and PA levels by 40%. The effects of these compounds on (/sup 32/Pi) labeling of the phosphoinositides and PA are consistent with an inhibition of flux through the inositide cycle, presumably through the action of cAMP. Such an inhibition may account for the reduction in carbamylcholine sensitive IP/sub 1/ accumulation observed in brain slices. These studies indicate that in rat brain, ..beta..-adrenergic stimulation may be involved in modulating the activity of muscarinic cholinergic agonists. This regulation appears to be at the level of inositol lipid metabolism.

  7. The RpiR-like repressor IolR regulates inositol catabolism in Sinorhizobium meliloti.

    PubMed

    Kohler, Petra R A; Choong, Ee-Leng; Rossbach, Silvia

    2011-10-01

    Sinorhizobium meliloti, the nitrogen-fixing symbiont of alfalfa, has the ability to catabolize myo-, scyllo-, and D-chiro-inositol. Functional inositol catabolism (iol) genes are required for growth on these inositol isomers, and they play a role during plant-bacterium interactions. The inositol catabolism genes comprise the chromosomally encoded iolA (mmsA) and the iolY(smc01163)RCDEB genes, as well as the idhA gene located on the pSymB plasmid. Reverse transcriptase assays showed that the iolYRCDEB genes are transcribed as one operon. The iol genes were weakly expressed without induction, but their expression was strongly induced by myo-inositol. The putative transcriptional regulator of the iol genes, IolR, belongs to the RpiR-like repressor family. Electrophoretic mobility shift assays demonstrated that IolR recognized a conserved palindromic sequence (5'-GGAA-N6-TTCC-3') in the upstream regions of the idhA, iolY, iolR, and iolC genes. Complementation assays found IolR to be required for the repression of its own gene and for the downregulation of the idhA-encoded myo-inositol dehydrogenase activity in the presence and absence of inositol. Further expression studies indicated that the late pathway intermediate 2-keto-5-deoxy-D-gluconic acid 6-phosphate (KDGP) functions as the true inducer of the iol genes. The iolA (mmsA) gene encoding methylmalonate semialdehyde dehydrogenase was not regulated by IolR. The S. meliloti iolA (mmsA) gene product seems to be involved in more than only the inositol catabolic pathway, since it was also found to be essential for valine catabolism, supporting its more recent annotation as mmsA.

  8. Two inositol hexakisphosphate kinases drive inositol pyrophosphate synthesis in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inositol pyrophosphates are novel cellular signaling molecules with newly discovered roles in energy sensing and metabolic control. Studies in eukaryotes have revealed that these compounds turn over rapidly, and thus only small amounts accumulate. Inositol pyrophosphates have not been the subject of...

  9. Dynamic changes in the distribution of minerals in relation to phytic acid accumulation during rice seed development.

    PubMed

    Iwai, Toru; Takahashi, Michiko; Oda, Koshiro; Terada, Yasuko; Yoshida, Kaoru T

    2012-12-01

    Phytic acid (inositol hexakisphosphate [InsP(6)]) is the storage compound of phosphorus in seeds. As phytic acid binds strongly to metallic cations, it also acts as a storage compound of metals. To understand the mechanisms underlying metal accumulation and localization in relation to phytic acid storage, we applied synchrotron-based x-ray microfluorescence imaging analysis to characterize the simultaneous subcellular distribution of some mineral elements (phosphorus, calcium, potassium, iron, zinc, and copper) in immature and mature rice (Oryza sativa) seeds. This fine-imaging method can reveal whether these elements colocalize. We also determined their accumulation patterns and the changes in phosphate and InsP(6) contents during seed development. While the InsP(6) content in the outer parts of seeds rapidly increased during seed development, the phosphate contents of both the outer and inner parts of seeds remained low. Phosphorus, calcium, potassium, and iron were most abundant in the aleurone layer, and they colocalized throughout seed development. Zinc was broadly distributed from the aleurone layer to the inner endosperm. Copper localized outside the aleurone layer and did not colocalize with phosphorus. From these results, we suggest that phosphorus translocated from source organs was immediately converted to InsP(6) and accumulated in aleurone layer cells and that calcium, potassium, and iron accumulated as phytic acid salt (phytate) in the aleurone layer, whereas zinc bound loosely to InsP(6) and accumulated not only in phytate but also in another storage form. Copper accumulated in the endosperm and may exhibit a storage form other than phytate.

  10. The D-chiro-inositol paradox in the ovary.

    PubMed

    Carlomagno, Gianfranco; Unfer, Vittorio; Roseff, Scott

    2011-06-30

    The D-chiro-inositol-to-myo-inositol ratio is regulated by an insulin-dependent epimerase. Enzyme activity varies among tissues, likely owing to the specific needs of the two different molecules. We hypothesize that in the ovaries of polycystic ovary syndrome patients, epimerase activity is enhanced, leading to a local myo-inositol deficiency which in turn is responsible for the poor oocyte quality.

  11. Sorption of organic phosphates and its effects on aggregation of hematite nanoparticles in monovalent and bivalent solutions.

    PubMed

    Xu, Chen-Yang; Li, Jiu-Yu; Xu, Ren-Kou; Hong, Zhi-Neng

    2017-01-18

    Sorption of organic phosphates-myo-inositol hexakisphosphate (IHP) and glycerol phosphate (GP) and its effects on the early stage of hematite aggregation kinetics were investigated at different pH and electrolyte composition. KH2PO4 (KP) was taken as an inorganic P source for comparison. Results indicated that for all types of P, the sorption amounts decreased with increasing solution pH. Sorption amount of IHP was almost two times that of KP, while those of GP and KP were close. Both organic P and inorganic P interacted with hematite via ligand exchange through their phosphate groups, which conveyed negative charges to mineral surface and significantly decreased the zeta potential of hematite. In Na(+) solution, critical coagulation concentrations (CCCs) of hematite suspensions increased with increasing P concentration and followed the order of KP < GP < IHP at pH 5.5. Compared with KP, the organic P could more effectively stabilize the hematite suspension not only through increasing the negative charges and electrostatic repulsive force, but also through steric repulsion between P-sorbed hematite nanoparticles. When the pH was increased from 5.5 to 10.0, the CCCs of the hematite suspensions with GP and IHP decreased mainly because of the great reductions in organic P sorption amounts and consequent decreases in electrostatic and steric repulsive forces. However, enhanced aggregation was observed in the presence of IHP at pH 4.5 and above in low Ca(2+) solutions. The precipitation of calcium phytate formed net-like structure, which served as bridges to bind hematite nanoparticles and resulted in enhanced aggregation. These results have important implications for assessing the fate and transport of organic P and hematite nanoparticles in soil and aquatic environments.

  12. Effect of exogenous phytase on feed inositol phosphate hydrolysis in an in vitro rumen fluid buffer system.

    PubMed

    Brask-Pedersen, D N; Glitsø, L V; Skov, L K; Lund, P; Sehested, J

    2011-02-01

    Three in vitro experiments using a rumen fluid buffer system were performed to investigate the effect of addition of 4 experimental phytases (Phy1, Phy2, Phy3, and Phy4) compared with no addition of phytase on feed inositol phosphate hydrolysis in wheat and rapeseed cake to determine which of the 4 phytases was most suitable under rumen-like conditions. The feedstuffs were incubated with a mixture of physiological buffer, ruminal fluid, and exogenous phytase at pH 6.2, after which the samples were incubated for different periods. Incubations were stopped using HCl, and the samples were analyzed for inositol phosphates via high performance ion chromatography. Addition of phytase (Phy1) resulted in enhanced degradation of myo-inositol hexakisphosphate (InsP(6)) in rapeseed cake, whereas addition of exogenous phytase did not improve the degradation of InsP(6) in wheat. Only rapeseed cake was therefore used subsequently. All 4 phytases increased degradation of InsP(6) in rapeseed cake in the in vitro system, and degradability of InsP(6) increased with higher incubation time and higher phytase dosages, independent of phytase. Addition of 2 units of phytase per gram of substrate of the phytases Phy1, Phy2, Phy3, and Phy4 led to an undegraded InsP(6) content of 56, 49, 70, and 18%, respectively, when incubated with rapeseed cake for 6h, indicating that Phy2 and Phy4 were the most effective phytases. However, Phy2 had a higher specific activity than Phy4, as 60% of the original InsP(6) content was remaining after 3h when 5mg of enzyme protein per gram of substrate of Phy2 was added to rapeseed cake, whereas 150 mg of enzyme protein per gram of substrate of Phy4 was necessary to achieve a similar result. Therefore, Phy2 appeared to be most applicable under rumen-like conditions.

  13. A type IV translocated Legionella cysteine phytase counteracts intracellular growth restriction by phytate.

    PubMed

    Weber, Stephen; Stirnimann, Christian U; Wieser, Mara; Frey, Daniel; Meier, Roger; Engelhardt, Sabrina; Li, Xiaodan; Capitani, Guido; Kammerer, Richard A; Hilbi, Hubert

    2014-12-05

    The causative agent of Legionnaires' pneumonia, Legionella pneumophila, colonizes diverse environmental niches, including biofilms, plant material, and protozoa. In these habitats, myo-inositol hexakisphosphate (phytate) is prevalent and used as a phosphate storage compound or as a siderophore. L. pneumophila replicates in protozoa and mammalian phagocytes within a unique "Legionella-containing vacuole." The bacteria govern host cell interactions through the Icm/Dot type IV secretion system (T4SS) and ∼300 different "effector" proteins. Here we characterize a hitherto unrecognized Icm/Dot substrate, LppA, as a phytate phosphatase (phytase). Phytase activity of recombinant LppA required catalytically essential cysteine (Cys(231)) and arginine (Arg(237)) residues. The structure of LppA at 1.4 Å resolution revealed a mainly α-helical globular protein stabilized by four antiparallel β-sheets that binds two phosphate moieties. The phosphates localize to a P-loop active site characteristic of dual specificity phosphatases or to a non-catalytic site, respectively. Phytate reversibly abolished growth of L. pneumophila in broth, and growth inhibition was relieved by overproduction of LppA or by metal ion titration. L. pneumophila lacking lppA replicated less efficiently in phytate-loaded Acanthamoeba castellanii or Dictyostelium discoideum, and the intracellular growth defect was complemented by the phytase gene. These findings identify the chelator phytate as an intracellular bacteriostatic component of cell-autonomous host immunity and reveal a T4SS-translocated L. pneumophila phytase that counteracts intracellular bacterial growth restriction by phytate. Thus, bacterial phytases might represent therapeutic targets to combat intracellular pathogens.

  14. Defective Craniofacial Development and Brain Function in a Mouse Model for Depletion of Intracellular Inositol Synthesis*

    PubMed Central

    Ohnishi, Tetsuo; Murata, Takuya; Watanabe, Akiko; Hida, Akiko; Ohba, Hisako; Iwayama, Yoshimi; Mishima, Kazuo; Gondo, Yoichi; Yoshikawa, Takeo

    2014-01-01

    myo-Inositol is an essential biomolecule that is synthesized by myo-inositol monophosphatase (IMPase) from inositol monophosphate species. The enzymatic activity of IMPase is inhibited by lithium, a drug used for the treatment of mood swings seen in bipolar disorder. Therefore, myo-inositol is thought to have an important role in the mechanism of bipolar disorder, although the details remain elusive. We screened an ethyl nitrosourea mutant mouse library for IMPase gene (Impa) mutations and identified an Impa1 T95K missense mutation. The mutant protein possessed undetectable enzymatic activity. Homozygotes died perinatally, and E18.5 embryos exhibited striking developmental defects, including hypoplasia of the mandible and asymmetric fusion of ribs to the sternum. Perinatal lethality and morphological defects in homozygotes were rescued by dietary myo-inositol. Rescued homozygotes raised on normal drinking water after weaning exhibited a hyper-locomotive trait and prolonged circadian periods, as reported in rodents treated with lithium. Our mice should be advantageous, compared with those generated by the conventional gene knock-out strategy, because they carry minimal genomic damage, e.g. a point mutation. In conclusion, our results reveal critical roles for intracellular myo-inositol synthesis in craniofacial development and the maintenance of proper brain function. Furthermore, this mouse model for cellular inositol depletion could be beneficial for understanding the molecular mechanisms underlying the clinical effect of lithium and myo-inositol-mediated skeletal development. PMID:24554717

  15. 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 ...

  16. 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 ...

  17. 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 ...

  18. A Segment of 97 Amino Acids within the Translocation Domain of Clostridium difficile Toxin B Is Essential for Toxicity

    PubMed Central

    Zhang, Yongrong; Shi, Lianfa; Li, Shan; Yang, Zhiyong; Standley, Clive; Yang, Zhong; ZhuGe, Ronghua; Savidge, Tor; Wang, Xiaoning; Feng, Hanping

    2013-01-01

    Clostridium difficile toxin B (TcdB) intoxicates target cells by glucosylating Rho GTPases. TcdB (269 kDa) consists of at least 4 functional domains including a glucosyltransferase domain (GTD), a cysteine protease domain (CPD), a translocation domain (TD), and a receptor binding domain (RBD). The function and molecular mode of action of the TD, which is the largest segment of TcdB and comprises nearly 50% of the protein, remain largely unknown. Here we show that a 97-amino-acid segment (AA1756 – 1852, designated as ?97 or D97), located in the C-terminus of the TD and adjacent to the RBD, is essential for the cellular activity of TcdB. Deletion of this segment in TcdB (designated as TxB-D97), did not adversely alter toxin enzymatic activities or its cellular binding and uptake capacity. TxB-D97 bound to and entered cells in a manner similar to TcdB holotoxin. Both wild type and mutant toxins released their GTDs similarly in the presence of inositol hexakisphosphate (InsP6), and showed a similar glucosyltransferase activity in a cell-free glucosylating assay. Despite these similarities, the cytotoxic activity of TxB-D97 was reduced by more than 5 logs compared to wild type toxin, supported by the inability of TxB-D97 to glucosylate Rac1 of target cells. Moreover, the mutant toxin failed to elicit tumor necrosis factor alpha (TNF-α) in macrophages, a process dependent on the glucosyltransferase activity of the toxin. Cellular fractionation of toxin-exposed cells revealed that TxB-D97 was unable to efficiently release the GTD into cytosol. Thereby, we conclude the 97-amino-acid region of the TD C-terminus of TcdB adjacent to the RBD, is essential for the toxicity of TcdB. PMID:23484044

  19. Effects of roasting on taste-active compounds of Turkish hazelnut varieties ( Corylus avellana L.).

    PubMed

    Alasalvar, Cesarettin; Pelvan, Ebru; Amarowicz, Ryszard

    2010-08-11

    The effect of roasting on taste-active components of 18 native hazelnut varieties, grown in the Giresun province of Turkey, was assessed. Samples were examined for their sugars, organic acids, condensed tannins, and free phenolic acids. Six sugars (fructose, glucose, sucrose, myo-inositol, raffinose, and stachyose), seven organic acids (oxalic, maleic, citric, malic, lactic, succinic, and acetic), and one phenolic acid (gallic acid) were positively identified in natural and roasted hazelnut varieties; among these, sucrose, malic acid, and gallic acid predominated, respectively. Total sugars among hazelnut varieties ranged from 1.99 to 4.94 g/100 g, organic acids from 0.96 to 2.72 g/100 g, condensed tannins from 3.99 to 40.56 mg of catechin equivalents/g, and gallic acid from 0.159 to 0.871 mg/100 g. Differences existed in the sugar and organic acid contents between natural and roasted hazelnut varieties, but they did not follow any particular trend. Significant losses (p < 0.05) in condensed tannins ( approximately 97.3%) and gallic acid ( approximately 66.7%) were noted when the hazelnuts were roasted. The present work suggests that roasting resulted in significant loss in condensed tannins and gallic acid due to the removal of the brown skin. The effect of roasting on sugars and organic acids was not noteworthy.

  20. 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.

  1. Metabolomics analysis in rats after administration of Datura stramonium.

    PubMed

    Zhang, Meiling; Bao, Shihui; Lin, Feiou; Lin, Yingying; Zhang, Lijing; Xu, Mengzhi; Huang, Xueli; Wen, Congcong; Hu, Lufeng; Lin, Guanyang

    2015-01-01

    This study aimed to evaluate the effect of Datura stramonium on rats by examining the differences in urine and serum metabolites between Datura stramonium groups and control group. SIMCA-P+12.0.1.0 software was used for partial least-squares discriminant analysis (PLS-DA) to screen for the differential metabolites. Fifteen metabolites in urine including malonic acid, pentanedioic acid, D-xylose, D-ribose, xylulose, azelaic acid, threitol, glycine, butanoic acid, D-mannose, D-gluconic acid, galactonic acid, myo-inositol, octadecanoic acid, pseudouridine and ten metabolites in serum including alanine, butanedioic acid, L-methionine, propanedioic acid, hexadecanoic acid, D-fructose, tetradecanoic acid, D-glucose, D-galactose, oleic acid were selected as the characteristic metabolites. The PLS-DA scores plot indicated that serum and urine metabolites have a variety of changes among low dose group, high dose group and control group. These metabolites were related with amino metabolism, lipid metabolism and energy metabolism. The result reflected the relationship between metabolites in rat fluid and Datura stramonium spectra. Potential differences in metabolites and metabolic pathway analysis showed that the establishment of urine and serum metabolomics methods for further evaluating drug has great significance.

  2. Metabolomics analysis in rats after administration of Datura stramonium

    PubMed Central

    Zhang, Meiling; Bao, Shihui; Lin, Feiou; Lin, Yingying; Zhang, Lijing; Xu, Mengzhi; Huang, Xueli; Wen, Congcong; Hu, Lufeng; Lin, Guanyang

    2015-01-01

    This study aimed to evaluate the effect of Datura stramonium on rats by examining the differences in urine and serum metabolites between Datura stramonium groups and control group. SIMCA-P+12.0.1.0 software was used for partial least-squares discriminant analysis (PLS-DA) to screen for the differential metabolites. Fifteen metabolites in urine including malonic acid, pentanedioic acid, D-xylose, D-ribose, xylulose, azelaic acid, threitol, glycine, butanoic acid, D-mannose, D-gluconic acid, galactonic acid, myo-inositol, octadecanoic acid, pseudouridine and ten metabolites in serum including alanine, butanedioic acid, L-methionine, propanedioic acid, hexadecanoic acid, D-fructose, tetradecanoic acid, D-glucose, D-galactose, oleic acid were selected as the characteristic metabolites. The PLS-DA scores plot indicated that serum and urine metabolites have a variety of changes among low dose group, high dose group and control group. These metabolites were related with amino metabolism, lipid metabolism and energy metabolism. The result reflected the relationship between metabolites in rat fluid and Datura stramonium spectra. Potential differences in metabolites and metabolic pathway analysis showed that the establishment of urine and serum metabolomics methods for further evaluating drug has great significance. PMID:26885052

  3. 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)

  4. Enzymic synthesis of indole-3-acetyl-1-O-beta-d-glucose. II. Metabolic characteristics of the enzyme

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

    The synthesis of indole-3-acetyl-1-O-beta-D-glucose from indole-3-acetic acid (IAA) and uridine diphosphoglucose (UDPG) has been shown to be a reversible reaction with the equilibrium away from ester formation and toward formation of IAA. The enzyme occurs primarily in the liquid endosperm of the corn kernel but some activity occurs in the embryo. It is relatively specific showing no glucose ester formation with oxindole-3-acetic acid or 7-hydroxy-oxindole-3-acetic acid, and low activity with phenylpropene acids, such as rho-coumaric acid. The enzyme is also specific for the nucleotide sugar showing no activity with UDPGalactose or UDPXylose. The enzyme is inhibited by inorganic pyrophosphate, by phosphate esters and by phospholipids, particularly phosphatidyl ethanolamine. The enzyme is inhibited by zeatin, by 2,4-dichlorophenoxy-acetic acid, by IAA-myo-inositol and IAA-glucan, but not by zeatin riboside, and only weakly by gibberellic acid, abscisic acid and kinetin. The reaction is slightly stimulated by both calcium and calmodulin and, in some cases, by thiol compounds. The role of this enzyme in the homeostatic control of indole-3-acetic acid levels in Zea mays is discussed.

  5. 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 ...

  6. 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 ...

  7. 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 ...

  8. 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 ...

  9. 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 ...

  10. 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 ...

  11. 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 . ...

  12. Osmoregulatory inositol transporter SMIT1 modulates electrical activity by adjusting PI(4,5)P2 levels

    PubMed Central

    Dai, Gucan; Yu, Haijie; Traynor-Kaplan, Alexis

    2016-01-01

    Myo-inositol is an important cellular osmolyte in autoregulation of cell volume and fluid balance, particularly for mammalian brain and kidney cells. We find it also regulates excitability. Myo-inositol is the precursor of phosphoinositides, key signaling lipids including phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2]. However, whether myo-inositol accumulation during osmoregulation affects signaling and excitability has not been fully explored. We found that overexpression of the Na+/myo-inositol cotransporter (SMIT1) and myo-inositol supplementation enlarged intracellular PI(4,5)P2 pools, modulated several PI(4,5)P2-dependent ion channels including KCNQ2/3 channels, and attenuated the action potential firing of superior cervical ganglion neurons. Further experiments using the rapamycin-recruitable phosphatase Sac1 to hydrolyze PI(4)P and the P4M probe to visualize PI(4)P suggested that PI(4)P levels increased after myo-inositol supplementation with SMIT1 expression. Elevated relative levels of PIP and PIP2 were directly confirmed using mass spectrometry. Inositol trisphosphate production and release of calcium from intracellular stores also were augmented after myo-inositol supplementation. Finally, we found that treatment with a hypertonic solution mimicked the effect we observed with SMIT1 overexpression, whereas silencing tonicity-responsive enhancer binding protein prevented these effects. These results show that ion channel function and cellular excitability are under regulation by several “physiological” manipulations that alter the PI(4,5)P2 setpoint. We demonstrate a previously unrecognized linkage between extracellular osmotic changes and the electrical properties of excitable cells. PMID:27217553

  13. 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. ...

  14. 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...

  15. 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.

  16. 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.

  17. 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.

  18. The Effect of Phytase on the Oxygen Isotope Composition of Phosphate

    NASA Astrophysics Data System (ADS)

    von Sperber, C.; Tamburini, F.; Bernasconi, S. M.; Frossard, E.

    2013-12-01

    for acid phosphatases (6). In contrast, the results from assays with phytase from Aspergillus niger indicate that the exchange of oxygen occurs at more than one third of the total 24 oxygen which are associated to the phosphates in IP6. In addition, we observe a change in the oxygen isotope composition of Pi when using myo-inositol and potassium-dihydrogen-phosphate as sole substrates in the enzymatic assays with phytase from Aspergillus niger. These observations suggest that the reformation of IP6 from the two products of the reaction (myo-inositol and Pi) is taking place at a rate, which is within the time scale of the experiment. In this case, the isotopic fractionation caused by phytase from Aspergillus niger will be determined by the equilibrium of the reaction. Further experiments are in process to verify these findings.

  19. Differential expression of structural genes for the late phase of phytic acid biosynthesis in developing seeds of wheat (Triticum aestivum L.).

    PubMed

    Bhati, Kaushal Kumar; Aggarwal, Sipla; Sharma, Shivani; Mantri, Shrikant; Singh, Sudhir P; Bhalla, Sherry; Kaur, Jagdeep; Tiwari, Siddharth; Roy, Joy K; Tuli, Rakesh; Pandey, Ajay K

    2014-07-01

    In cereals, phytic acid (PA) or inositol hexakisphosphate (IP6) is a well-known phosphate storage compound as well as major chelator of important micronutrients (iron, zinc, calcium, etc.). Genes involved in the late phases of PA biosynthesis pathway are known in crops like maize, soybeans and barley but none have been reported from wheat. Our in silico analysis identified six wheat genes that might be involved in the biosynthesis of inositol phosphates. Four of the genes were inositol tetraphosphate kinases (TaITPK1, TaITPK2, TaITPK3, and TaITPK4), and the other two genes encode for inositol triphosphate kinase (TaIPK2) and inositol pentakisphosphate kinase (TaIPK1). Additionally, we identified a homolog of Zmlpa-1, an ABCC subclass multidrug resistance-associated transporter protein (TaMRP3) that is putatively involved in PA transport. Analyses of the mRNA expression levels of these seven genes showed that they are differentially expressed during seed development, and that some are preferentially expressed in aleurone tissue. These results suggest selective roles during PA biosynthesis, and that both lipid-independent and -dependent pathways are active in developing wheat grains. TaIPK1 and TaMRP3 were able to complement the yeast ScΔipk1 and ScΔycf1 mutants, respectively, providing evidence that the wheat genes have the expected biochemical functions. This is the first comprehensive study of the wheat genes involved in the late phase of PA biosynthesis. Knowledge generated from these studies could be utilized to develop strategies for generating low phyate wheat.

  20. 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)

  1. (1)H NMR-based metabolomics study on a goldfish model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).

    PubMed

    Lu, Zhaoguang; Wang, Junsong; Li, Minghui; Liu, Qingwang; Wei, Dandan; Yang, Minghua; Kong, Lingyi

    2014-11-05

    A goldfish (Carassius auratus) model of Parkinson's disease (PD) was constructed by a single dose of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) according to previously reported methods. Global metabolite changes in brain of the MPTP induced goldfish model of PD were investigated. (1)H NMR-based metabolomics combined with various statistical methods such as orthogonal partial least squares discriminant analysis (OPLS-DA) and two-dimensional statistical total correlation spectroscopy (2D-STOCSY) found significant increase of leucine, isoleucine, valine, alanine, alanylalanine, creatinine, myo-inositol, 18:2 fatty acid, total fatty acids, arachic alcohol, taurine and significant decrease of N-acetylaspartate, (phospho)creatine, (phospho)choline, betaine, glutamine, 3-hexenedioate, acetamide, malonate, isocitrate, scyllo-inositol, phosphatidylcholines, cholesterols, n-3 fatty acids, polyunsaturated fatty acids (PUFAs) in brain of MPTP induced PD goldfish. These disturbed metabolite levels were involved in oxidative stress, energy failure, neuronal cell injury and death, consistent with those observed in clinical PD patients, and rodents and primates model of PD, indicating that the acute MPTP model of goldfish was an ideal and valuable model for PD research. In addition, several unusual metabolites in brain were significantly changed between MPTP induced PD and control goldfish, which might also play an important role in the pathogenesis of PD. This study also demonstrated the applicability and potential of (1)H NMR-based metabolomics approach for evaluation of animal models of disease induced by chemicals, such as MPTP-induced PD goldfish.

  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. Successful and not so successful chemoprevention of tobacco smoke-induced lung tumors.

    PubMed

    Witschi, H

    2000-12-01

    Strain A/J mice underwent whole body exposure for 6 hours a day, 5 days a week, for 5 months to a mixture of cigarette sidestream and mainstream smoke (89%-11%; total suspended particulates 80-150 mg/m3), then were kept for another 4 months in air before being killed for scoring of lung tumors. In 7 independent experiments, lung tumor multiplicity was significantly increased in all 7 trials and lung tumor incidence in 5. When animals were kept for 9 months in smoke, lung tumor multiplicity was not significantly higher than in controls, although lung tumor incidence was. The following chemopreventive agents were evaluated: green tea, phenethyl isothiocyanate (PEITC), acetylsalicylic acid (ASA), N-acetylcysteine (NAC), p-XSC (1,4-phenylenebis[methylene]selenocyanate), d-limonene (DL), and a mixture of PEITC and BITC (benzyl isothiocyanate). In animals exposed to tobacco smoke, none of these agents reduced lung tumor multiplicity or incidence. As a control, the effects of the same agents were examined in A/J mice initiated with 4-(methylnitrosamino)-1-(3pyridyl)-1-butanone (NNK) or urethane. In mice injected with NNK, green tea and ASA did not reduce lung tumor multiplicities and NAC had no effect on urethane-induced lung tumors, whereas PEITC, p-XSC and DL reduced NNK-induced tumor multiplicities to 20% to 50% of control values. On the other hand, dietary mixture of myoinositol and dexamethasone was not only highly protective against NNK, but reduced lung tumor multiplicities and incidence in smoke-exposed animals to control values. This effect was also seen when the animals were fed the myo-inositol-dexamethasone mixture once they were removed from smoke. It is concluded that in animal studies it might be preferable to evaluate the effectiveness of putative chemopreventive agents against full tobacco smoke rather than against selected model compounds. The observations made with myo-inositol-dexamethasone suggest that people who have recently quit smoking might

  8. Development of a method for enhancing metabolomics coverage of human sweat by gas chromatography-mass spectrometry in high resolution mode.

    PubMed

    Delgado-Povedano, M M; Calderón-Santiago, M; Priego-Capote, F; Luque de Castro, M D

    2016-01-28

    Sweat has recently gained popularity as clinical sample in metabolomics analysis as it is a non-invasive biofluid the composition of which could be modified by certain pathologies, as is the case with cystic fibrosis that increases chloride levels in sweat. However, the whole composition of sweat is still unknown and there is a lack of analytical strategies for sweat analysis. The aim of the present study was to develop and validate a method for metabolomic analysis of human sweat by gas chromatography-time of flight/mass spectrometry (GC-TOF/MS) in high resolution mode. Thus, different sample preparation strategies were compared to check their effect on the profile of sweat metabolites. Sixty-six compounds were tentatively identified by the obtained MS information. Amino acids, dicarboxylic acids and other interesting metabolites such as myo-inositol and urocanic acid were identified. Among the tested protocols, methyoxiamination plus silylation after deproteinization was the most suited option to obtain a representative snapshot of sweat metabolome. The intra-day repeatability of the method ranged from 0.60 to 16.99% and the inter-day repeatability from 2.75 to 31.25%. As most of the identified metabolites are involved in key biochemical pathways, this study opens new possibilities to the use of sweat as a source of metabolite biomarkers of specific disorders.

  9. GC-TOF/MS-based metabolomics approach to study the cellular immunotoxicity of deoxynivalenol on murine macrophage ANA-1 cells.

    PubMed

    Ji, Jian; Sun, Jiadi; Pi, Fuwei; Zhang, Shuang; Sun, Chao; Wang, Xiumei; Zhang, Yinzhi; Sun, Xiulan

    2016-08-25

    Gas chromatography-time of fly/mass spectrum (GC-TOF/MS) based complete murine macrophage ANA-1 cell metabolome strategy, including the endo-metabolome and the exo-metabolome, ANA-1 cell viability assays and apoptosis induced by diverse concentrations of DON were evaluated for selection of an optimized dose for in-depth metabolomic research. Using the optimized chromatography and mass spectrometry parameters, the metabolites detected by GC-TOF/MS were identified and processed with multivariate statistical analysis, including principal componentanalysis (PCA) and orthogonal projection to latent structures-discriminant analysis (OPLS-DA) analysis. The data sets were screened with a t-test (P) value < 0.05, VIP value > 1, similarity value > 500, leaving 16 exo-metabolite variables and 11 endo-metabolite variables for further pathway analysis. Implementing the integration of key metabolic pathways, the metabolism pathways were categorized into two dominating types, metabolism of amino acid and glycometabolism. Glycine, serine and threonine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis and phenylalanine metabolism were the significant amino acids affected by the metabolic pathways, indicating statistically significant fold changes including pyruvate, serine, glycine, lactate and threonine. Glycolysis or gluconeogenesis, starch and sucrose metabolism, and galactose metabolism, belonging to glycometabolism, were the pathways that were found to be primarily affected, resulting in abnormal metabolites such as glucose-1P, Glucose, gluconic acid, myo-inositol, sorbitol and glycerol.

  10. Accumulation of Phosphorus-Containing Compounds in Developing Seeds of Low-Phytate Pea (Pisum sativum L.) Mutants

    PubMed Central

    Shunmugam, Arun S.K.; Bock, Cheryl; Arganosa, Gene C.; Georges, Fawzy; Gray, Gordon R.; Warkentin, Thomas D.

    2014-01-01

    Low phytic acid (lpa) crops are low in phytic acid and high in inorganic phosphorus (Pi). In this study, two lpa pea genotypes, 1-150-81, 1-2347-144, and their progenitor CDC Bronco were grown in field trials for two years. The lpa genotypes were lower in IP6 and higher in Pi when compared to CDC Bronco. The total P concentration was similar in lpa genotypes and CDC Bronco throughout the seed development. The action of myo-inositol phosphate synthase (MIPS) (EC 5.5.1.4) is the first and rate-limiting step in the phytic acid biosynthesis pathway. Aiming at understanding the genetic basis of the lpa mutation in the pea, a 1530 bp open reading frame of MIPS was amplified from CDC Bronco and the lpa genotypes. Sequencing results showed no difference in coding sequence in MIPS between CDC Bronco and lpa genotypes. Transcription levels of MIPS were relatively lower at 49 days after flowering (DAF) than at 14 DAF for CDC Bronco and lpa lines. This study elucidated the rate and accumulation of phosphorus compounds in lpa genotypes. The data also demonstrated that mutation in MIPS was not responsible for the lpa trait in these pea lines. PMID:27135314

  11. Dynamic metabonomic responses of tobacco (Nicotiana tabacum) plants to salt stress.

    PubMed

    Zhang, Jingtao; Zhang, Yong; Du, Yuanyuan; Chen, Shiyun; Tang, Huiru

    2011-04-01

    Metabolic responses are important for plant adaptation to osmotic stresses. To understand the dosage and duration dependence of salinity effects on plant metabolisms, we analyzed the metabonome of tobacco plants and its dynamic responses to salt treatments using NMR spectroscopy in combination with multivariate data analysis. Our results showed that the tobacco metabonome was dominated by 40 metabolites including organic acids/bases, amino acids, carbohydrates and choline, pyrimidine, and purine metabolites. A dynamic trajectory was clearly observable for the tobacco metabonomic responses to the dosage of salinity. Short-term low-dose salt stress (50 mM NaCl, 1 day) caused metabolic shifts toward gluconeogenesis with depletion of pyrimidine and purine metabolites. Prolonged salinity with high-dose salt (500 mM NaCl) induced progressive accumulation of osmolytes, such as proline and myo-inositol, and changes in GABA shunt. Such treatments also promoted the shikimate-mediated secondary metabolisms with enhanced biosynthesis of aromatic amino acids. Therefore, salinity caused systems alterations in widespread metabolic networks involving transamination, TCA cycle, gluconeogenesis/glycolysis, glutamate-mediated proline biosynthesis, shikimate-mediated secondary metabolisms, and the metabolisms of choline, pyrimidine, and purine. These findings provided new insights for the tobacco metabolic adaptation to salinity and demonstrated the NMR-based metabonomics as a powerful approach for understanding the osmotic effects on plant biochemistry.

  12. 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.

  13. 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.

  14. Free cyclitol, soluble carbohydrate and protein contents in Vigna unguiculata and Phaseolus vulgaris bean sprouts.

    PubMed

    Ribeiro, Elane da Silva; Centeno, Danilo da Cruz; Figueiredo-Ribeiro, Rita de Cássia; Fernandes, Kátia Valevski Sales; Xavier-Filho, José; Oliveira, Antônia Elenir Amancio

    2011-04-27

    Seeds sprouts have been used as a good source of basic nutrients and nutraceutical compounds. The high nutritional value of seeds derives from the deposition of compounds during development. However some of these molecules are used in metabolic processes like germination, which leads to a considerable variation in their concentrations once these events are completed. In this work, we investigate the levels of inositols (myo-inositol, D-pinitol and ononitol), soluble carbohydrates and proteins in cotyledons of Phaseolus vulgaris and Vigna unguiculata sprouts. Sprouting increased myo-inositol and glucose content and reduction of raffinose and ononitol was observed. The protein levels increased in P. vulgaris and decreased in V. unguiculata sprouting. The level of sucrose was maintained in both sprouts. D-Pinitol was detected only in quiescent seeds. Our results suggested that bean sprout is an important source of proteins, sucrose, glucose and myo-inositol. Additionally, bean sprouts have low levels of raffinose, an antinutritional compound.

  15. 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

  16. Metabolomic screening of pre-diagnostic serum samples identifies association between α- and γ-tocopherols and glioblastoma risk

    PubMed Central

    Björkblom, Benny; Wibom, Carl; Jonsson, Pär; Mörén, Lina; Andersson, Ulrika; Johannesen, Tom Børge; Langseth, Hilde; Antti, Henrik; Melin, Beatrice

    2016-01-01

    Glioblastoma is associated with poor prognosis with a median survival of one year. High doses of ionizing radiation is the only established exogenous risk factor. To explore new potential biological risk factors for glioblastoma, we investigated alterations in metabolite concentrations in pre-diagnosed serum samples from glioblastoma patients diagnosed up to 22 years after sample collection, and undiseased controls. The study points out a latent biomarker for future glioblastoma consisting of nine metabolites (γ-tocopherol, α-tocopherol, erythritol, erythronic acid, myo-inositol, cystine, 2-keto-L-gluconic acid, hypoxanthine and xanthine) involved in antioxidant metabolism. We detected significantly higher serum concentrations of α-tocopherol (p=0.0018) and γ-tocopherol (p=0.0009) in future glioblastoma cases. Compared to their matched controls, the cases showed a significant average fold increase of α- and γ-tocopherol levels: 1.2 for α-T (p=0.018) and 1.6 for γ-T (p=0.003). These tocopherol levels were associated with a glioblastoma odds ratio of 1.7 (α-T, 95% CI:1.0-3.0) and 2.1 (γ-T, 95% CI:1.2-3.8). Our exploratory metabolomics study detected elevated serum levels of a panel of molecules with antioxidant properties as well as oxidative stress generated compounds. Additional studies are necessary to confirm the association between the observed serum metabolite pattern and future glioblastoma development. PMID:27175595

  17. Characterization of the salt stress vulnerability of three invasive freshwater plant species using a metabolic profiling approach.

    PubMed

    Thouvenot, Lise; Deleu, Carole; Berardocco, Solenne; Haury, Jacques; Thiébaut, Gabrielle

    2015-03-01

    The effects of salt stress on freshwater plants has been little studied up to now, despite the fact that they are expected to present different levels of salt sensitivity or salt resistance depending on the species. The aim of this work was to assess the effect of NaCl at two concentrations on three invasive freshwater species, Elodea canadensis, Myriophyllum aquaticum and Ludwigia grandiflora, by examining morphological and physiological parameters and using metabolic profiling. The growth rate (biomass and stem length) was reduced for all species, whatever the salt treatment, but the response to salt differed between the three species, depending on the NaCl concentration. For E. canadensis, the physiological traits and metabolic profiles were only slightly modified in response to salt, whereas M. aquaticum and L. grandiflora showed great changes. In both of these species, root number, photosynthetic pigment content, amino acids and carbohydrate metabolism were affected by the salt treatments. Moreover, we are the first to report the salt-induced accumulation of compatible solutes in both species. Indeed, in response to NaCl, L. grandiflora mainly accumulated sucrose. The response of M. aquaticum was more complex, because it accumulated not only sucrose and myo-inositol whatever the level of salt stress, but also amino acids such as proline and GABA, but only at high NaCl concentrations. These responses are the metabolic responses typically found in terrestrial plants.

  18. UDP-sugar pyrophosphorylase is essential for arabinose and xylose recycling, and is required during vegetative and reproductive growth in Arabidopsis.

    PubMed

    Geserick, Claudia; Tenhaken, Raimund

    2013-04-01

    Numerous nucleotide sugars are needed in plants to synthesize cell wall polymers and glycoproteins. The de novo synthesis of nucleotide sugars is of major importance. During growth, however, some polymers are broken down to monosaccharides. Reactivation of these sugars into nucleotide sugars occurs in two steps: first, by a substrate-specific sugar-1-kinase and, second, by UDP-sugar-pyrophosphorylase (USP), which has broad substrate specificity. A knock-out of the USP gene results in non-fertile pollen. By using various genetic complementation approaches we obtained a strong (>95%) knock-down line in USP that allowed us to investigate the physiological role of the enzyme during the life cycle. Mutant plants show an arabinose reduction in the cell wall, and accumulate mainly two sugars, arabinose and xylose, in the cytoplasm. The arabinogalactanproteins in usp mutants show no significant reduction in size. USP is also part of the myo-inositol oxygenation pathway to UDP-glucuronic acid; however, free glucuronic acid does not accumulate in cells, suggesting alternative conversion pathways of this monosaccharide. The knock-down plants are mostly sterile because of the improper formation of anthers and pollen sacks.

  19. Metabolomic identification of biochemical changes induced by fluoxetine and imipramine in a chronic mild stress mouse model of depression.

    PubMed

    Zhao, Jing; Jung, Yang-Hee; Jang, Choon-Gon; Chun, Kwang-Hoon; Kwon, Sung Won; Lee, Jeongmi

    2015-03-09

    Metabolomics was applied to a C57BL/6N mouse model of chronic unpredictable mild stress (CMS). Such mice were treated with two antidepressants from different categories: fluoxetine and imipramine. Metabolic profiling of the hippocampus was performed using gas chromatography-mass spectrometry analysis on samples prepared under optimized conditions, followed by principal component analysis, partial least squares-discriminant analysis, and pair-wise orthogonal projections to latent structures discriminant analyses. Body weight measurement and behavior tests including an open field test and the forced swimming test were completed with the mice as a measure of the phenotypes of depression and antidepressive effects. As a result, 23 metabolites that had been differentially expressed among the control, CMS, and antidepressant-treated groups demonstrated that amino acid metabolism, energy metabolism, adenosine receptors, and neurotransmitters are commonly perturbed by drug treatment. Potential predictive markers for treatment effect were identified: myo-inositol for fluoxetine and lysine and oleic acid for imipramine. Collectively, the current study provides insights into the molecular mechanisms of the antidepressant effects of two widely used medications.

  20. Metabolomic identification of biochemical changes induced by fluoxetine and imipramine in a chronic mild stress mouse model of depression

    NASA Astrophysics Data System (ADS)

    Zhao, Jing; Jung, Yang-Hee; Jang, Choon-Gon; Chun, Kwang-Hoon; Kwon, Sung Won; Lee, Jeongmi

    2015-03-01

    Metabolomics was applied to a C57BL/6N mouse model of chronic unpredictable mild stress (CMS). Such mice were treated with two antidepressants from different categories: fluoxetine and imipramine. Metabolic profiling of the hippocampus was performed using gas chromatography-mass spectrometry analysis on samples prepared under optimized conditions, followed by principal component analysis, partial least squares-discriminant analysis, and pair-wise orthogonal projections to latent structures discriminant analyses. Body weight measurement and behavior tests including an open field test and the forced swimming test were completed with the mice as a measure of the phenotypes of depression and antidepressive effects. As a result, 23 metabolites that had been differentially expressed among the control, CMS, and antidepressant-treated groups demonstrated that amino acid metabolism, energy metabolism, adenosine receptors, and neurotransmitters are commonly perturbed by drug treatment. Potential predictive markers for treatment effect were identified: myo-inositol for fluoxetine and lysine and oleic acid for imipramine. Collectively, the current study provides insights into the molecular mechanisms of the antidepressant effects of two widely used medications.

  1. Metabolic Analysis of Medicinal Dendrobium officinale and Dendrobium huoshanense during Different Growth Years

    PubMed Central

    Jin, Qing; Jiao, Chunyan; Sun, Shiwei; Song, Cheng; Cai, Yongping; Lin, Yi; Fan, Honghong; Zhu, Yanfang

    2016-01-01

    Metabolomics technology has enabled an important method for the identification and quality control of Traditional Chinese Medical materials. In this study, we isolated metabolites from cultivated Dendrobium officinale and Dendrobium huoshanense stems of different growth years in the methanol/water phase and identified them using gas chromatography coupled with mass spectrometry (GC-MS). First, a metabolomics technology platform for Dendrobium was constructed. The metabolites in the Dendrobium methanol/water phase were mainly sugars and glycosides, amino acids, organic acids, alcohols. D. officinale and D. huoshanense and their growth years were distinguished by cluster analysis in combination with multivariate statistical analysis, including principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). Eleven metabolites that contributed significantly to this differentiation were subjected to t-tests (P<0.05) to identify biomarkers that discriminate between D. officinale and D. huoshanense, including sucrose, glucose, galactose, succinate, fructose, hexadecanoate, oleanitrile, myo-inositol, and glycerol. Metabolic profiling of the chemical compositions of Dendrobium species revealed that the polysaccharide content of D. huoshanense was higher than that of D. officinale, indicating that the D. huoshanense was of higher quality. Based on the accumulation of Dendrobium metabolites, the optimal harvest time for Dendrobium was in the third year. This initial metabolic profiling platform for Dendrobium provides an important foundation for the further study of secondary metabolites (pharmaceutical active ingredients) and metabolic pathways. PMID:26752292

  2. Expression of bifidobacterial phytases in Lactobacillus casei and their application in a food model of whole-grain sourdough bread.

    PubMed

    García-Mantrana, Izaskun; Yebra, María J; Haros, Monika; Monedero, Vicente

    2016-01-04

    Phytases are enzymes capable of sequentially dephosphorylating phytic acid to products of lower chelating capacity and higher solubility, abolishing its inhibitory effect on intestinal mineral absorption. Genetic constructions were made for expressing two phytases from bifidobacteria in Lactobacillus casei under the control of a nisin-inducible promoter. L. casei was able of producing, exporting and anchoring to the cell wall the phytase of Bifidobacterium pseudocatenulatum. The phytase from Bifidobacterium longum spp. infantis was also produced, although at low levels. L. casei expressing any of these phytases completely degraded phytic acid (2mM) to lower myo-inositol phosphates when grown in MRS medium. Owing to the general absence of phytase activity in lactobacilli and to the high phytate content of whole grains, the constructed L. casei strains were applied as starter in a bread making process using whole-grain flour. L. casei developed in sourdoughs by fermenting the existing carbohydrates giving place to an acidification. In this food model system the contribution of L. casei strains expressing phytases to phytate hydrolysis was low, and the phytate degradation was mainly produced by activation of the cereal endogenous phytase as a consequence of the drop in pH. This work shows the capacity of lactobacilli to be modified in order to produce enzymes with relevance in food technology processes. The ability of these strains in reducing the phytate content in fermented food products must be evaluated in further models.

  3. Separation and quantification of microalgal carbohydrates.

    PubMed

    Templeton, David W; Quinn, Matthew; Van Wychen, Stefanie; Hyman, Deborah; Laurens, Lieve M L

    2012-12-28

    Structural carbohydrates can constitute a large fraction of the dry weight of algal biomass and thus accurate identification and quantification is important for summative mass closure. Two limitations to the accurate characterization of microalgal carbohydrates are the lack of a robust analytical procedure to hydrolyze polymeric carbohydrates to their respective monomers and the subsequent identification and quantification of those monosaccharides. We address the second limitation, chromatographic separation of monosaccharides, here by identifying optimum conditions for the resolution of a synthetic mixture of 13 microalgae-specific monosaccharides, comprised of 8 neutral, 2 amino sugars, 2 uronic acids and 1 alditol (myo-inositol as an internal standard). The synthetic 13-carbohydrate mix showed incomplete resolution across 11 traditional high performance liquid chromatography (HPLC) methods, but showed improved resolution and accurate quantification using anion exchange chromatography (HPAEC) as well as alditol acetate derivatization followed by gas chromatography (for the neutral- and amino-sugars only). We demonstrate the application of monosaccharide quantification using optimized chromatography conditions after sulfuric acid analytical hydrolysis for three model algae strains and compare the quantification and complexity of monosaccharides in analytical hydrolysates relative to a typical terrestrial feedstock, sugarcane bagasse.

  4. An all-aqueous route to polymer brush-modified membranes with remarkable permeabilites and protein capture rates

    PubMed Central

    Anuraj, Nishotha; Bhattacharjee, Somnath; Geiger, James H.; Baker, Gregory L.; Bruening, Merlin L.

    2011-01-01

    Microporous membranes are attractive for protein purification because convection rapidly brings proteins to binding sites. However, the low binding capacity of such membranes limits their applications. This work reports a rapid, aqueous procedure to create highly permeable, polymer brush-modified membranes that bind large amounts of protein. The synthetic method includes a 10-min adsorption of a macroinitiator in a hydroxylated nylon membrane and a subsequent 5-min aqueous atom transfer radical polymerization of 2-(methacryloyloxy)ethyl succinate from the immobilized initiator to form poly(acid) brushes. This procedure likely leads to more swollen, less dense brushes than polymerization from silane initiators, and thus requires less polymer to achieve the same binding capacity. The hydraulic permeability of the poly(acid) membranes is 4-fold higher than that of similar membranes prepared by growing brushes from immobilized silane initiators. These brush-containing nylon membranes bind 120 mg/cm3 of lysozyme using solution residence times as short as 35 ms, and when functionalized with nitrilotriacetate (NTA)-Ni2+ complexes, they capture 85 mg/cm3 of histidine6-tagged (His-tagged) Ubiquitin. Additionally the NTA-Ni2+-functionalized membranes isolate His-tagged myo-inositol-1-phosphate synthase directly from cell extracts and show >90% recovery of His-tagged proteins. PMID:22287817

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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)

  15. Uncoupling of attenuated myo-(3H)inositol uptake and dysfunction in Na(+)-K(+)-ATPase pumping activity in hypergalactosemic cultured bovine lens epithelial cells

    SciTech Connect

    Cammarata, P.R.; Tse, D.; Yorio, T. )

    1991-06-01

    Attenuation of both the active transport of myo-inositol and Na(+)-K(+)-ATPase pumping activity has been implicated in the onset of sugar cataract and other diabetic complications in cell culture and animal models of the disease. Cultured bovine lens epithelial cells (BLECs) maintained in galactose-free Eagle's minimal essential medium (MEM) or 40 mM galactose with and without sorbinil for up to 5 days were examined to determine the temporal effects of hypergalactosemia on Na(+)-K(+)-ATPase and myo-inositol uptake. The Na(+)-K(+)-ATPase pumping activity after 5 days of continuous exposure to galactose did not change, as demonstrated by 86Rb uptake. The uptake of myo-(3H)inositol was lowered after 20 h of incubation in galactose and remained below that of the control throughout the 5-day exposure period. The coadministration of sorbinil to the galactose medium normalized the myo-(3H)inositol uptake. No significant difference in the rates of passive efflux of myo-(3H)inositol or 86Rb from preloaded galactose-treated and control cultures was observed. Culture-media reversal studies were also carried out to determine whether the galactose-induced dysfunction in myo-inositol uptake could be corrected. BLECs were incubated in galactose for 5 days, then changed to galactose-free physiological medium with and without sorbinil for a 1-day recovery period. myo-Inositol uptake was reduced to 34% of control after 6 days of continuous exposure to galactose. Within 24 h of media reversal, myo-inositol uptake returned to or exceeded control values in BLECs switched to either MEM or MEM with sorbinil.2+ reversible and occurred independently of changes in Na(+)-K(+)-ATPase pumping activity in cultured lens epithelium, indicating that the two parameters are not strictly associated and that the deficit in myo-inositol uptake occurs rapidly during hypergalactosemia.

  16. Bacillus phytases: present scenario and future perspectives.

    PubMed

    Fu, Shijun; Sun, Jianyi; Qian, Lichun; Li, Zhiyu

    2008-10-01

    Phytases are a special class of phosphatases that catalyze the sequential hydrolysis of phytate to less-phosphorylated myo-inositol derivatives and inorganic phosphate. Bacillus phytases, which exhibit their desirable activity profile under neutral pH, higher thermal stability, and strict substrate specificity for the calcium-phytate complex, have considerable potential in commercial and environmental applications. This review describes recent findings concerning the production, biochemical properties, molecular characteristics, and expression of Bacillus phytases. Several potential applications of the Bacillus phytases in animal nutrition, human health, and synthesis of lower myo-inositol phosphates are also summarized.

  17. 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.

  18. Isomerization of 1-O-indol-3-ylacetyl-beta-D-glucose. Enzymatic hydrolysis of 1-O, 4-O, and 6-O-indol-3-ylacetyl-beta-D-glucose and the enzymatic synthesis of indole-3-acetyl glycerol by a hormone metabolizing complex

    NASA Technical Reports Server (NTRS)

    Kowalczyk, S.; Bandurski, R. S.

    1990-01-01

    The first compound in the series of reactions leading to the ester conjugates of indole-3-acetic acid (IAA) in kernels of Zea mays sweet corn is the acyl alkyl acetal, 1-O-indol-3-ylacetyl-beta-D-glucose (1-O-IAGlu). The enzyme catalyzing the synthesis of this compound is UDP-glucose:indol-3-ylacetate glucosyl-transferase (IAGlu synthase). The IAA moiety of the high energy compound 1-O-IAGlu may be enzymatically transferred to myo-inositol or to glycerol or the 1-O-IAGlu may be enzymatically hydrolyzed. Alternatively, nonenzymatic acyl migration may occur to yield the 2-O, 4-O, and 6-O esters of IAA and glucose. The 4-O and 6-O esters may then be enzymatically hydrolyzed to yield free IAA and glucose. This work reports new enzymatic activities, the transfer of IAA from 1-O-IAGlu to glycerol, and the enzyme-catalyzed hydrolysis of 4-O and 6-O-IAGlu. Data is also presented on the rate of non-enzymatic acyl migration of IAA from the 1-O to the 4-O and 6-O positions of glucose. We also report that enzymes catalyzing the synthesis of 1-O-IAGlu and the hydrolysis of 1-O, 4-O, and 6-O-IAGlu fractionate as a hormone metabolizing complex. The association of synthetic and hydrolytic capabilities in enzymes which cofractionate may have physiological significance.

  19. NMR-based metabolomics reveals brain region-specific metabolic alterations in streptozotocin-induced diabetic rats with cognitive dysfunction.

    PubMed

    Zheng, Hong; Lin, Qiuting; Wang, Dan; Xu, Pengtao; Zhao, Liangcai; Hu, Wenyi; Bai, Guanghui; Yan, Zhihan; Gao, Hongchang

    2017-04-01

    Diabetes mellitus (DM) can result in cognitive dysfunction, but its potential metabolic mechanisms remain unclear. In the present study, we analyzed the metabolite profiling in eight different brain regions of the normal rats and the streptozotocin (STZ)-induced diabetic rats accompanied by cognitive dysfunction using a (1)H NMR-based metabolomic approach. A mixed linear model analysis was performed to assess the effects of DM, brain region and their interaction on metabolic changes. We found that different brain regions in rats displayed significant metabolic differences. In addition, the hippocampus was more susceptible to DM compared with other brain regions in rats. More interestingly, significant interaction effects of DM and brain region were observed on alanine, creatine/creatine-phosphate, lactate, succinate, aspartate, glutamate, glutamine, γ-aminobutyric acid, glycine, choline, N-acetylaspartate, myo-inositol and taurine. Based on metabolic pathway analysis, we speculate that cognitive dysfunction in the STZ-induced diabetic rats may be associated with brain region-specific metabolic alterations involving energy metabolism, neurotransmitters, membrane metabolism and osmoregulation.

  20. Dickeyafangzhongdai sp. nov., a plant-pathogenic bacterium isolated from pear trees (Pyrus pyrifolia).

    PubMed

    Tian, Yanli; Zhao, Yuqiang; Yuan, Xiaoli; Yi, Jianping; Fan, Jiaqin; Xu, Zhigang; Hu, Baishi; De Boer, Solke H; Li, Xiang

    2016-09-01

    Gram-stain-negative, pectinolytic bacteria were repeatedly isolated from pear trees displaying symptoms of bleeding canker in China. Three strains, JS5T, LN1 and QZH3, had identical 16S rRNA gene sequences that shared 99 % similarity to the type strain of Dickeya dadantii. Phylogenetic analysis of strains JS5T, LN1 and QZH3 with isolates representing all species of the genus Dickeya and related Pectobacterium species supported their affiliation to Dickeya. Multi-locus sequence typing employing concatenated sequences encoding recA, fusA, gapA, purA, rplB, dnaX and the intergenic spacer illustrated a phylogeny which placed strains JS5T, LN1 and QZH3 as a distinct clade, separate from all other species of the genus Dickeya. Average nucleotide identity values obtained in comparison with all species of the genus Dickeya supported the distinctiveness of strain JS5T within the genus Dickeya. Additionally, all three strains were phenotypically distinguished from other species of the genus Dickeya by failing to hydrolyse casein, and by producing acids from (-)-d-arabinose, (+)melibiose, (+)raffinose, mannitol and myo-inositol, but not from 5-keto-d-gluconate or β-gentiobiose. The name Dickeya fangzhongdai sp. nov. is proposed to accommodate these strains; the type strain is JS5T (=CGMCC 1.15464T=DSM 101947T).

  1. Toward an in Vivo Neurochemical Profile: Quantification of 18 Metabolites in Short-Echo-Time 1H NMR Spectra of the Rat Brain

    NASA Astrophysics Data System (ADS)

    Pfeuffer, Josef; Tkáč , Ivan; Provencher, Stephen W.; Gruetter, Rolf

    1999-11-01

    Localized in vivo1H NMR spectroscopy was performed with 2-ms echo time in the rat brain at 9.4 T. Frequency domain analysis with LCModel showed that the in vivo spectra can be explained by 18 metabolite model solution spectra and a highly structured background, which was attributed to resonances with fivefold shorter in vivo T1 than metabolites. The high spectral resolution (full width at half maximum approximately 0.025 ppm) and sensitivity (signal-to-noise ratio approximately 45 from a 63-μL volume, 512 scans) was used for the simultaneous measurement of the concentrations of metabolites previously difficult to quantify in 1H spectra. The strongly represented signals of N-acetylaspartate, glutamate, taurine, myo-inositol, creatine, phosphocreatine, glutamine, and lactate were quantified with Cramér-Rao lower bounds below 4%. Choline groups, phosphorylethanolamine, glucose, glutathione, γ-aminobutyric acid, N-acetylaspartylglutamate, and alanine were below 13%, whereas aspartate and scyllo-inositol were below 22%. Intra-assay variation was assessed from a time series of 3-min spectra, and the coefficient of variation was similar to the calculated Cramér-Rao lower bounds. Interassay variation was determined from 31 pooled spectra, and the coefficient of variation for total creatine was 7%. Tissue concentrations were found to be in very good agreement with neurochemical data from the literature.

  2. In vivo high-resolution localized 1H MR spectroscopy in the awake rat brain at 7 Tesla

    PubMed Central

    Xu, Su; Ji, Yadong; Chen, Xi; Yang, Yihong; Gullapalli, Rao; Masri, Radi

    2012-01-01

    In vivo localized high-resolution 1H MR spectroscopy was performed in multiple brain regions without the use of anesthetic or paralytic agents in awake head-restrained rats that were previously trained in a simulated MRI environment using a 7 Tesla MR system. Spectra were obtained using a short echo time single-voxel point-resolved spectroscopy technique with voxel size ranging from 27–32.4 mm3 in the regions of anterior cingulate cortex, somatosensory cortex, hippocampus, and thalamus. Quantifiable spectra, without the need for any additional post-processing to correct for possible motion were reliably detected including the metabolites of interest such as γ-aminobutyric acid, glutamine, glutamate, myo-inositol, N-acetylaspartate, taurine, glycerophosphorylcholine/phosphorylcholine, creatine/phosphocreatine, and N-acetylaspartate/N-acetylaspartylglutamate. The spectral quality was comparable to spectra from anesthetized animals with sufficient spectral dispersion to separate metabolites such as glutamine and glutamate. Results from this study suggest that reliable information on major metabolites can be obtained without the confounding effects of anesthesia or paralytic agents in rodents. PMID:22570299

  3. Neurochemistry of Drug Action: Insights from Proton Magnetic Resonance Spectroscopic Imaging And Their Relevance to Addiction

    PubMed Central

    Licata, Stephanie C.; Renshaw, Perry F.

    2011-01-01

    Proton magnetic resonance spectroscopy (1H MRS) is a non-invasive imaging technique that permits measurement of particular compounds or metabolites within the tissue of interest. In the brain, 1H MRS provides a snapshot of the neurochemical environment within a defined volume of interest. A search of the literature demonstrates the widespread utility of this technique for characterizing tumors, tracking the progress of neurodegenerative disease, and for understanding the neurobiological basis of psychiatric disorders. As of relatively recently, 1H MRS has found its way into substance abuse research, and it is beginning to become recognized as a valuable complement in the brain imaging toolbox that also contains positron emission tomography (PET), single photon emission computed tomography (SPECT), and functional magnetic resonance imaging (fMRI). Drug abuse studies employing 1H MRS have identified a number biochemical changes in the brain. The most consistent alterations across drug class were reductions in N-acetylaspartate and elevations in myo-inositol, while changes in choline, creatine, and amino acid transmitters also were abundant. Together, the studies discussed herein provide evidence that drugs of abuse may have a profound impact on neuronal health, energy metabolism and maintenance, inflammatory processes, cell membrane turnover, and neurotransmission, and these biochemical changes may underlie the neuropathology within brain tissue that subsequently gives rise to the cognitive and behavioral impairments associated with drug addiction. PMID:20201852

  4. Differences in the effect of phosphatidylinositol 4,5-bisphosphate on the hydrolytic and transphosphatidylation activities of membrane-bound phospholipase D from poppy seedlings.

    PubMed

    Oblozinsky, Marek; Bezakova, Lydia; Mansfeld, Johanna; Heilmann, Ingo; Ulbrich-Hofmann, Renate

    2013-08-01

    The hydrolytic activity of phospholipase D (PLD) yielding phosphatidic acid from phosphatidylcholine and other glycerophospholipids is known to be involved in many cellular processes. In contrast, it is not clear whether the competitive transphosphatidylation activity of PLD catalyzing the head group exchange of phospholipids has a natural function. In poppy seedlings (Papaver somniferum L.) where lipid metabolism and alkaloid synthesis are closely linked, five isoenzymes with different substrate and hydrolysis/transphosphatidylation selectivities have been detected hitherto. A membrane-bound PLD, found in microsomal fractions of poppy seedlings, is active at micromolar concentrations of Ca(2+) ions and needs phosphatidylinositol 4,5-bisphosphate (PIP2) as effector in the hydrolysis of phosphatidylcholine (PC). The optimum PIP2 concentration at 1.2 mol% of the concentration of the substrate PC indicates a specific activation effect. Transphosphatidylation with glycerol, ethanolamine, l-serine, or myo-inositol as acceptor alcohols is also activated by PIP2, however, with an optimum concentration at 0.6-0.9 mol%. In contrast to hydrolysis, a basic transphosphatidylation activity occurs even in the absence of PIP2, suggesting a different fine-tuning of the two competing reactions.

  5. Ascorbate biosynthesis and its involvement in stress tolerance and plant development in rice (Oryza sativa L.).

    PubMed

    Höller, Stefanie; Ueda, Yoshiaki; Wu, Linbo; Wang, Yunxia; Hajirezaei, Mohammad-Reza; Ghaffari, Mohammad-Reza; von Wirén, Nicolaus; Frei, Michael

    2015-08-01

    Ascorbic acid (AsA) biosynthesis and its implications for stress tolerance and plant development were investigated in a set of rice knock-out (KO) mutants for AsA biosynthetic genes and their wild-types. KO of two isoforms of GDP-D-mannose epimerase (OsGME) reduced the foliar AsA level by 20-30%, and KO of GDP-L-galactose phosphorylase (OsGGP) by 80%, while KO of myo-inositol oxygenase (OsMIOX) did not affect foliar AsA levels. AsA concentration was negatively correlated with lipid peroxidation in foliar tissue under ozone stress and zinc deficiency, but did not affect the sensitivity to iron toxicity. Lack of AsA reduced the photosynthetic efficiency as represented by the maximum carboxylation rate of Rubisco (Vmax), the maximum electron transport rate (Jmax) and the chlorophyll fluorescence parameter ΦPSII. Mutants showed lower biomass production than their wild-types, especially when OsGGP was lacking (around 80% reductions). All plants except for KO mutants of OsGGP showed distinct peaks in foliar AsA concentrations during the growth, which were consistent with up-regulation of OsGGP, suggesting that OsGGP plays a pivotal role in regulating foliar AsA levels during different growth stages. In conclusion, our data demonstrate multiple roles of AsA in stress tolerance and development of rice.

  6. Neurochemistry of drug action: insights from proton magnetic resonance spectroscopic imaging and their relevance to addiction.

    PubMed

    Licata, Stephanie C; Renshaw, Perry F

    2010-02-01

    Proton magnetic resonance spectroscopy ((1)H MRS) is a noninvasive imaging technique that permits measurement of particular compounds or metabolites within the tissue of interest. In the brain, (1)H MRS provides a snapshot of the neurochemical environment within a defined volume of interest. A search of the literature demonstrates the widespread utility of this technique for characterizing tumors, tracking the progress of neurodegenerative disease, and for understanding the neurobiological basis of psychiatric disorders. As of relatively recently, (1)H MRS has found its way into substance abuse research, and it is beginning to become recognized as a valuable complement in the brain imaging toolbox that also contains positron emission tomography, single-photon-emission computed tomography, and functional magnetic resonance imaging. Drug abuse studies using (1)H MRS have identified several biochemical changes in the brain. The most consistent alterations across drug class were reductions in N-acetylaspartate and elevations in myo-inositol, whereas changes in choline, creatine, and amino acid transmitters also were abundant. Together, the studies discussed herein provide evidence that drugs of abuse may have a profound effect on neuronal health, energy metabolism and maintenance, inflammatory processes, cell membrane turnover, and neurotransmission, and these biochemical changes may underlie the neuropathology within brain tissue that subsequently gives rise to the cognitive and behavioral impairments associated with drug addiction.

  7. Is N,N-dimethylglycine N-oxide a choline and betaine metabolite?

    PubMed

    Lever, Michael; McEntyre, Christopher J; George, Peter M; Chambers, Stephen T

    2017-01-13

    Choline metabolism is by oxidation to betaine, which is demethylated to N,N-dimethylglycine; dimethylglycine is oxidatively demethylated to sarcosine. This pathway is important for osmoregulation and as a source of methyl groups. We asked whether another metabolite was involved. We synthesized the N-oxide of dimethylglycine (DMGO) by oxidizing dimethylglycine with peracetic acid, and measured DMGO in human plasma and urine by HPLC-MS/MS with positive ion detection, using two chromatography procedures, based on ion exchange and HILIC separations. The molecular ion DMGOH+ (m/z=120) yielded four significant fragments (m/z=103, 102, 58 and 42). The suspected DMGO peak in human body fluids showed all these fragments, and co-chromatographed with added standard DMGO in both HPLC systems. Typical plasma concentrations of DMGO are under 1 μmol/l. They may be lower in metabolic syndrome patients. Urine concentrations are higher, and DMGO has a higher fractional clearance than dimethylglycine, betaine and choline. It was present in all of over 80 human urine and plasma samples assayed. Plasma DMGO concentrations correlate with plasma DMG concentrations, with betaine and choline concentrations, with the osmolyte myo-inositol, and strongly with urinary DMGO excretion. We conclude that DMGO is probably a normal human metabolite.

  8. Neurochemical profile of the human cervical spinal cord determined by MRS.

    PubMed

    Hock, Andreas; Wilm, Bertram; Zandomeneghi, Giorgia; Ampanozi, Garyfalia; Franckenberg, Sabine; Zoelch, Niklaus; Wyss, Patrik Oliver; De Zanche, Nicola; Nordmeyer-Maßner, Jurek; Kraemer, Thomas; Thali, Michael; Ernst, Matthias; Kollias, Spyros; Henning, Anke

    2016-10-01

    MRS enables insight into the chemical composition of central nervous system tissue. However, technical challenges degrade the data quality when applied to the human spinal cord. Therefore, to date detection of only the most prominent metabolite resonances has been reported in the healthy human spinal cord. The aim of this investigation is to provide an extended metabolic profile including neurotransmitters and antioxidants in addition to metabolites involved in the energy and membrane metabolism of the human cervical spinal cord in vivo. To achieve this, data quality was improved by using a custom-made, cervical detector array together with constructive averaging of a high number of echo signals, which is enabled by the metabolite cycling technique at 3T. In addition, the improved spinal cord spectra were extensively cross-validated, in vivo, post-mortem in situ and ex vivo. Reliable identification of up to nine metabolites was achieved in group analyses for the first time. Distinct features of the spinal cord neurochemical profile, in comparison with the brain neurotransmission system, include decreased concentrations of the sum of glutamate and glutamate and increased concentrations of aspartate, γ-amino-butyric acid, scyllo-inositol and the sum of myo-inositol and glycine.

  9. Metabolic changes in rat prefrontal cortex and hippocampus induced by chronic morphine treatment studied ex vivo by high resolution 1H NMR spectroscopy.

    PubMed

    Gao, Hongchang; Xiang, Yun; Sun, Ninglei; Zhu, Hang; Wang, Yaqiang; Liu, Maili; Ma, Yuanye; Lei, Hao

    2007-01-01

    Ex vivo(1)H NMR spectroscopy was used to measure changes in the concentrations of cerebral metabolites in the prefrontal cortex (PFC) and hippocampus of rats subjected to repeated morphine treatment known to cause tolerance/dependence. The results show that repeated morphine exposure induces significant changes in the concentrations of a number of cerebral metabolites, and such changes are region specific. After 10 days of repeated morphine treatment, the concentration of gamma-aminobutyric acid (GABA) increased significantly in the PFC (20+/-11%), but decreased in the hippocampus (-31+/-12%), compared to control. In contrast, the glutamate (Glu) concentrations in both the PFC (-15+/-8%) and hippocampus (-13+/-4%) decreased significantly. Significant changes were also observed in the concentrations of hippocampal glutamine (Gln), myo-inositol, taurine, and N-acetyl aspartate. These morphine-induced changes were reversed during a subsequent 5-day withdrawal period. It is suggested that the observed concentration changes for Glu, Gln and GABA are most likely the result of a shift in the steady-state equilibrium of the Gln-Glu-GABA metabolic cycle. Changes in the metabolism of this neurotransmitter system might be part of the adaptive measures taken by the central nervous system in response to repeated morphine exposure and subsequent withdrawal.

  10. A quantitative analysis of 1H-MR spectroscopy at 3.0 T of three brain regions from childhood to middle age

    PubMed Central

    Yang, Z-Y; Yue, Q; Xing, H-Y; Tan, Q-Y; Sun, H-Q; Gong, Q-Y; Tan, Z-J

    2015-01-01

    Objective: To study age-related metabolic changes in different brain regions. Methods: Point-resolved spectroscopy (repetition time/echo time = 2000 ms/30 ms) was performed in the left and right hippocampus, the left thalamus and the left centrum semiovale of 80 healthy subjects (37 females and 43 males aged 7–64 years). Analysis of covariance and linear regression were used for statistical analysis. Both metabolite concentration ratios with respect to total creatine (tCr) and absolute metabolite concentrations were included for analysis. Results: Ins (myo-inositol)/tCr (p < 0.001) and absolute Ins concentration (p = 0.031) were significantly increased with age after adolescence. NAA (N-acetylaspartic acid)/tCr (p < 0.001) and absolute NAA concentration (p = 0.010) significantly declined with age after adolescence. Conclusion: Age-related increase of Ins and decline of NAA are found in all three regions, especially at the hippocampus, indicating possible gliosis in the ageing brain. Advances in knowledge: We could use NAA/tCr and Ins/tCr as an indicator to estimate the neurons-to-glial cells ratio at the thalamus. This may be an index to distinguish normal tissues from gliosis. PMID:26081448

  11. Exercise ameliorates insulin resistance via Ca2+ signals distinct from those of insulin for GLUT4 translocation in skeletal muscles.

    PubMed

    Park, Dae-Ryoung; Park, Kwang-Hyun; Kim, Byung-Ju; Yoon, Chung-Su; Kim, Uh-Hyun

    2015-04-01

    Muscle contraction and insulin induce glucose uptake in skeletal muscle through GLUT4 membrane translocation. Beneficial effects of exercise on glucose homeostasis in insulin-resistant individuals are known to be due to their distinct mechanism between contraction and insulin action on glucose uptake in skeletal muscle. However, the underlying mechanisms are not clear. Here we show that in skeletal muscle, distinct Ca(2+) second messengers regulate GLUT4 translocation by contraction and insulin treatment; d-myo-inositol 1,4,5-trisphosphate/nicotinic acid adenine dinucleotide phosphate (NAADP) and cyclic ADP-ribose/NAADP are main players for insulin- and contraction-induced glucose uptake, respectively. Different patterns of phosphorylation of AMPK and Ca(2+)/calmodulin-dependent protein kinase II were shown in electrical stimuli (ES)- and insulin-induced glucose uptake pathways. ES-induced Ca(2+) signals and glucose uptake are dependent on glycolysis, which influences formation of NAD(P)-derived signaling messengers, whereas insulin-induced signals are not. High-fat diet (HFD) induced a defect in only insulin-mediated, but not ES-mediated, Ca(2+) signaling for glucose uptake, which is related to a specifically lower NAADP formation. Exercise decreases blood glucose levels in HFD-induced insulin resistance mice via NAADP formation. Thus we conclude that different usage of Ca(2+) signaling in contraction/insulin-stimulated glucose uptake in skeletal muscle may account for the mechanism by which exercise ameliorates glucose homeostasis in individuals with type 2 diabetes.

  12. Evaluation of carbohydrates in natural and cultured Cordyceps by pressurized liquid extraction and gas chromatography coupled with mass spectrometry.

    PubMed

    Guan, Jia; Yang, Feng-Qing; Li, Shao-Ping

    2010-06-11

    Free and polymeric carbohydrates in Cordyceps, a valued edible mushroom and well-known traditional Chinese medicine, were determined using stepwise pressurized liquid extraction (PLE) extraction and GC-MS. Based on the optimized PLE conditions, acid hydrolysis and derivatization, ten monosaccharides, namely rhamnose, ribose, arabinose, xylose, mannose, glucose, galactose, mannitol, fructose and sorbose in 13 samples of natural and cultured Cordyceps were qualitatively and quantitatively analyzed and compared with myo-inositol hexaacetate as internal standard. The results showed that natural C. sinensis contained more than 7.99% free mannitol and a small amount of glucose, while its polysaccharides were usually composed of mannose, glucose and galactose with a molar ratio of 1.00:16.61-3.82:1.60-1.28. However, mannitol in cultured C. sinensis and cultured C. militaris were less than 5.83%, and free glucose was only detected in a few samples, while their polysaccharides were mainly composed of mannose, glucose and galactose with molar ratios of 1.00:3.01-1.09:3.30-1.05 and 1.00:2.86-1.28:1.07-0.78, respectively. Natural and cultured Cordyceps could be discriminated by hierarchical clustering analysis based on its free carbohydrate contents.

  13. Chemical and physicochemical quality parameters in carrots dehydrated by power ultrasound.

    PubMed

    Soria, Ana Cristina; Corzo-Martínez, Marta; Montilla, Antonia; Riera, Enrique; Gamboa-Santos, Juliana; Villamiel, Mar

    2010-07-14

    Preservation of the quality and bioactivity of carrots dehydrated by power ultrasound (US) under different experimental conditions including prior blanching has been evaluated for the first time by measuring the evolution of the Maillard reaction and the changes in soluble sugars, proteins, total polyphenols, antioxidant activity, and rehydration ability. This study also includes a comparison with a freeze-dried sample and data of commercial dehydrated carrots. The synergic effect of US and temperature (60 degrees C) increased the dehydration rate of carrots (90% moisture loss in only 75 min) while still providing carrots with a level of 2-furoylmethyl-amino acids significantly lower than that of dehydrated commercial samples. Whereas a decrease in the content of reducing soluble sugars was observed with processing temperature, minor carbohydrates (scyllo- and myo-inositol and sedoheptulose) were rather stable, irrespective of the US dehydration parameters. Blanching significantly improved the rehydration ability of US-dehydrated carrots without increasing the loss of soluble sugars by leaching. As supported by the similarity of most quality indicators studied in both US-treated and freeze-dried carrots, the mild processing conditions employed in US dehydration gave rise to premium quality dehydrated carrots.

  14. PhyA gene product of Aspergillus ficuum and Peniophora lycii produces dissimilar phytases.

    PubMed

    Ullah, Abul H J; Sethumadhavan, Kandan

    2003-04-04

    PhyA gene products of Aspergillus ficuum (AF) and Peniophora lycii (PL) as expressed in industrial strains of Aspergillus niger and Aspergillus oryzae, respectively, were purified to homogeneity and then characterized for both physical and biochemical properties. The PL phytase is 26 amino acid residues shorter than the AF phytase. Dynamic light scattering studies indicate that the active AF phytase is a monomer while the PL phytase is a dimer. While both of the phytases retained four identical glycosylatable Asn residues, unique glycosylation sites, six for PL and seven for AF phytase, were observed. Global alignment of both the phytases has shown 38% sequence homology between the two proteins. At 58 degrees C and pH 5.0, the PL phytase gave a specific activity of 22,000 nKat/mg as opposed to about 3000 nKat/mg for AF phytase. However, the AF phytase is more thermostable than its counterpart PL phytase at 65 degrees C. Also, AF phytase is more stable at pH 7.5 than the PL phytase. The two phytases differed in K(m) for phytate, K(i) for myo-inositol hexasulfate (MIHS), and pH optima profile. Despite similarities in the active site sequences, the two phytases show remarkable differences in turnover number, pH optima profile, stability at higher temperature, and alkaline pH. These biochemical differences indicate that phytases from ascomycete and basidiomycete fungi may have evolved to degrade phytate in different environments.

  15. Organic solutes in the deepest phylogenetic branches of the Bacteria: identification of α(1-6)glucosyl-α(1-2)glucosylglycerate in Persephonella marina.

    PubMed

    Lamosa, Pedro; Rodrigues, Marta V; Gonçalves, Luís G; Carr, Jean; Ventura, Rita; Maycock, Christopher; Raven, Neil D; Santos, Helena

    2013-01-01

    The accumulation of organic solutes was investigated in the thermophilic bacteria Persephonella marina and Marinitoga piezophila, two representatives of the deepest lineages in the domain Bacteria. These organisms grow optimally at around 70 °C in medium containing 3 % NaCl. A new disaccharide, accumulating in Persephonella marina, was identified as α(1-6)glucosyl-α(1-2)glucosylglycerate (GGG), by nuclear magnetic resonance. This identification was validated by comparison with the spectra of the compound obtained by chemical synthesis. Besides GGG, the solute pool of Persephonella marina comprised β-glutamate, di-myo-inositol-1,3'-phosphate and 2-O-α-glucosylglycerate. In contrast, amino acids such as α-glutamate, proline and alanine were the dominant components of the solute pool of Marinitoga piezophila and sugar derivatives were absent. The ability of GGG to protect protein structure against heat denaturation was assessed using model proteins. A genomic search for the biosynthetic pathways of known ionic solutes in Aquificales and Thermotogales shows the inability of this analysis to predict the nature of compatible solutes and underlines the need for efficient cultivation techniques.

  16. Functional drug screening reveals anticonvulsants as enhancers of mTOR-independent autophagic killing of Mycobacterium tuberculosis through inositol depletion.

    PubMed

    Schiebler, Mark; Brown, Karen; Hegyi, Krisztina; Newton, Sandra M; Renna, Maurizio; Hepburn, Lucy; Klapholz, Catherine; Coulter, Sarah; Obregón-Henao, Andres; Henao Tamayo, Marcela; Basaraba, Randall; Kampmann, Beate; Henry, Katherine M; Burgon, Joseph; Renshaw, Stephen A; Fleming, Angeleen; Kay, Robert R; Anderson, Karen E; Hawkins, Phillip T; Ordway, Diane J; Rubinsztein, David C; Floto, Rodrigo Andres

    2015-02-01

    Mycobacterium tuberculosis (MTB) remains a major challenge to global health made worse by the spread of multidrug resistance. We therefore examined whether stimulating intracellular killing of mycobacteria through pharmacological enhancement of macroautophagy might provide a novel therapeutic strategy. Despite the resistance of MTB to killing by basal autophagy, cell-based screening of FDA-approved drugs revealed two anticonvulsants, carbamazepine and valproic acid, that were able to stimulate autophagic killing of intracellular M. tuberculosis within primary human macrophages at concentrations achievable in humans. Using a zebrafish model, we show that carbamazepine can stimulate autophagy in vivo and enhance clearance of M. marinum, while in mice infected with a highly virulent multidrug-resistant MTB strain, carbamazepine treatment reduced bacterial burden, improved lung pathology and stimulated adaptive immunity. We show that carbamazepine induces antimicrobial autophagy through a novel, evolutionarily conserved, mTOR-independent pathway controlled by cellular depletion of myo-inositol. While strain-specific differences in susceptibility to in vivo carbamazepine treatment may exist, autophagy enhancement by repurposed drugs provides an easily implementable potential therapy for the treatment of multidrug-resistant mycobacterial infection.

  17. Novel insights into the pathogenicity of epidemic Aeromonas hydrophila ST251 clones from comparative genomics

    PubMed Central

    Pang, Maoda; Jiang, Jingwei; Xie, Xing; Wu, Yafeng; Dong, Yuhao; Kwok, Amy H. Y.; Zhang, Wei; Yao, Huochun; Lu, Chengping; Leung, Frederick C.; Liu, Yongjie

    2015-01-01

    Outbreaks in fish of motile Aeromonad septicemia (MAS) caused by Aeromonas hydrophila have caused a great concern worldwide. Here, for the first time, we provide two complete genomes of epidemic A. hydrophila strains isolated in China. To gain an insight into the pathogenicity of epidemic A. hydrophila, we performed comparative genomic analyses of five epidemic strains belonging to sequence type (ST) 251, together with the environmental strain ATCC 7966T. We found that the known virulence factors, including a type III secretion system, a type VI secretion system and lateral flagella, are not required for the high virulence of the ST251 clonal group. Additionally, our work identifies three utilization pathways for myo-inositol, sialic acid and L-fucose providing clues regarding the factors that underlie the epidemic and virulent nature of ST251 A. hydrophila. Based on the geographical distribution and biological resources of the ST251 clonal group, we conclude that ST251 is a high-risk clonal group of A. hydrophila which may be responsible for the MAS outbreaks in China and the southeastern United States. PMID:26014286

  18. Molecular and biochemical identification of inositol 1,3,4,5,6-pentakisphosphate 2-kinase encoding mRNA variants in castor bean (Ricinus communis L.) seeds.

    PubMed

    Yu, Jaeju; Saiardi, Adolfo; Greenwood, John S; Bewley, J Derek

    2014-05-01

    During seed development, phytic acid (PA) associated with mineral cations is stored as phytin and mobilized following germination in support of seedling growth. Two parallel biosynthetic pathways for PA have been proposed; yet the pathway is still poorly understood in terms of its regulation and the enzymes involved. Here, the castor bean (Ricinus communis L.) gene for inositol 1,3,4,5,6-pentakisphosphate 2-kinase (RcIPK1) has been identified. This encodes the enzyme implicated in catalyzing the final reaction in PA biosynthesis, and its expression is enhanced in isolated germinated embryos by application of phosphate and myo-inositol (Ins). Even though only one copy of the RcIPK1 gene is present in the genome, numerous RNA variants are present, most likely due to alternative splicing. These are translated into six closely related protein isoforms according to in silico analysis. Functional analyses using yeast ipk1Δ revealed that only three of the mRNA variants can rescue a temperature-sensitive growth phenotype of this strain. High-performance liquid chromatography (HPLC) analysis of the synthesized inositol phosphates demonstrated that the ability to complement the missing yeast IPK1 enzyme is associated with the production of enzyme activity. The three active isoforms possess unique conserved motifs important for IPK1 catalytic activity.

  19. Influence of the input system (conventional versus organic farming) on metabolite profiles of maize ( Zea mays ) kernels.

    PubMed

    Röhlig, Richard M; Engel, Karl-Heinz

    2010-03-10

    Maize ( Zea mays ) kernels grown conventionally and organically, respectively, were investigated using a gas chromatography/mass spectrometry (GC/MS)-based metabolite profiling methodology. By analysis of three cultivars grown at two locations with different input systems and at a third location where both organic and conventional farming were applied, the impact of the growing regime on the metabolite spectrum should be put into the context of natural variability. The applied analytical approach involved consecutive extraction of freeze-dried maize flour and subsequent subfractionation. Approximately 300 compounds from a broad spectrum of chemical classes were detected, of which 167 were identified. The metabolite profiling data were statistically assessed via principal component analysis (PCA) and analysis of variance (ANOVA). The PCA demonstrated that the observed separations were mainly due to genetic differences (cultivars) and environmental influences. The different input systems (conventional/organic) only led to minor differentiations. ANOVA and quantification of selected constituents confirmed these observations. Only three metabolites (malic acid, myo-inositol, and phosphate) were consistently different because of the employed input system if samples from all field trials were considered.

  20. Superlubricity and tribochemistry of polyhydric alcohols

    NASA Astrophysics Data System (ADS)

    Matta, C.; Joly-Pottuz, L.; de Barros Bouchet, M. I.; Martin, J. M.; Kano, M.; Zhang, Qing; Goddard, W. A., III

    2008-08-01

    The anomalous low friction of diamondlike carbon coated surfaces lubricated by pure glycerol was observed at 80°C . Steel surfaces were coated with an ultrahard 1 µm thick hydrogen-free tetrahedral coordinated carbon (ta-C) layer produced by physical vapor deposition. In the presence of glycerol, the friction coefficient is below 0.01 at steady state, corresponding to the so-called superlubricity regime (when sliding is then approaching pure rolling). This new mechanism of superlow friction is attributed to easy glide on triboformed OH-terminated surfaces. In addition to the formation of OH-terminated surfaces but at a lower temperature, we show here some evidence, by coupling experimental and computer simulations, that superlow friction of polyhydric alcohols could also be associated with triboinduced degradation of glycerol, producing a nanometer-thick film containing organic acids and water. Second, we show outstanding superlubricity of steel surfaces directly lubricated by a solution of myo-inositol (also called vitamin Bh) in glycerol at ambient temperature (25°C) . For the first time, under boundary lubrication at high contact pressure, friction of steel is below 0.01 in the absence of any long chain polar molecules. The mechanism is still unknown but could be associated with friction-induced dissociation of glycerol and interaction of waterlike species with steel surface.

  1. Reconstitution of anti-allergic activities of PG102 derived from Actinidia arguta by combining synthetic chemical compounds.

    PubMed

    Kim, Donghyun; Choi, Jinyong; Kim, Mi-Jeong; Kim, Seon Hee; Cho, Sang Heon; Kim, Sunyoung

    2013-06-01

    PG102, a water-soluble extract from an edible fruit, Actinidia arguta, has previously been shown to control various factors involved in allergy pathogenesis. It was investigated whether the original activities of PG102 could be reconstituted by mixing chemical compounds present in PG102. Six compounds present in PG102 were, individually or in the form of mixtures, tested for their effects on the expression of various Th2 cytokines and inflammatory mediators in the cell-based assay. Each chemical inhibited IL-4 expression to varying degrees. The chemical compounds were combined at a ratio present in PG102, resulting in two formulations, CQMIIH and CQM, consisting of all or the first three of the following chemicals, citric, quinic, and malic acids, myo-inositol, isoquercitrin, and 5-hydroxymethyl-2-furaldehyde. The mixtures reconstituted original activities of PG102 to a significant level. In the murine asthma model, CQM ameliorated asthmatic symptoms and significantly decreased the level of IgE and IL-5. The decreased phosphorylation of ERK1/2 was observed in cells and mice treated with PG102 and the mixtures. Our data indicated that the substantial portion of PG102's anti-allergic activities could be reconstituted, in vitro and in vivo, by mixing six chemical compounds, suggesting the possibility of developing a new type of anti-allergic agent. This approach may be useful for developing chemically defined functional products from complex botanical extracts.

  2. Inositol's and other nutraceuticals' synergistic actions counteract insulin resistance in polycystic ovarian syndrome and metabolic syndrome: state-of-the-art and future perspectives.

    PubMed

    Paul, Cristiana; Laganà, Antonio Simone; Maniglio, Paolo; Triolo, Onofrio; Brady, David M

    2016-06-01

    The incidence of metabolic syndrome (MetS), type II diabetes (T2D) and polycystic ovarian syndrome (PCOS) has been progressively increasing. Insulin resistance (InsR) seems to play a key role in a majority of phenotypes of these conditions, altering metabolic homeostasis, within muscle, liver, adipose and other tissues. Hyperinsulinemia is often associated with InsR and causes hormonal imbalances especially within ovaries and adrenals. Inositol is a polyalcohol, naturally occurring as nine stereoisomers, including D-chiro-inositol (DCI) and myo-inositol (MI), which have prominent roles in the metabolism of glucose and free fatty acids. MI and DCI have been classified as insulin-sensitizers and seem to adequately counteract several InsR-related metabolic alterations with a safe nutraceutical profile. Based on our analysis of selected studies that investigated MI and/or DCI, we conclude that supplementation with MI and/or DCI complement each other in their metabolic actions and act in synergy with other insulin sensitizing drugs and/or nutraceuticals. Nevertheless, considering the possible severe bias due to different methodologies across published studies, we conclude that there is a need for further studies on larger cohorts and with greater statistical power. These should further clarify outcomes and suitable therapeutic dosages of MI and DCI, possibly based on each patient's clinical status.

  3. 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

  4. 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 ...

  5. 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…

  6. 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...

  7. 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...

  8. 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.

  9. [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.

  10. 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.

  11. 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 ...

  12. 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 ...

  13. 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 ...

  14. 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 ...

  15. 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 ...

  16. 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 ...

  17. 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? ...

  18. 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.

  19. Synthesis of Differentially Protected myo- and chiro-Inositols from D-Xylose; Stereoselectivity in Intramolecular SmI2-Promoted Pinacol Reactions

    PubMed Central

    Luchetti, Giovanni; Ding, Kejia

    2009-01-01

    Methods for the enantioselective conversion of D-xylose to differentially protected myo-inositol and L-chiro-inositol have been developed. The key transformation is a highly diastereoselective intramolecular SmI2-promoted pinacol coupling. The stereoselectivity was extremely dependent on the conditions, suggesting a change in mechanism. Preliminary mechanistic experiments and possible explanations for this behavior are discussed. PMID:20622936

  20. Enantio- and Diastereodivergent Synthetic Route to Multifarious Cyclitols from D-Xylose via Ring-Closing Metathesis

    PubMed Central

    Luchetti, Giovanni; Ding, Kejia; d'Alarcao, Marc; Kornienko, Alexander

    2009-01-01

    Short stereoselective syntheses of various cyclitols, including the derivatives of conduritol B, conduritol F, myo-inositol and chiro-inositol, have been accomplished. The key steps in the syntheses are a ring-closing metathesis process and a diastereodivergent organometallic addition to a D-xylose-derived alde-hyde. PMID:19802347

  1. Salt-induced abnormalities on root tip mitotic cells of Allium cepa: prevention by inositol pretreatment.

    PubMed

    Chatterjee, Jolly; Majumder, Arun Lahiri

    2010-09-01

    Salt-induced growth reduction of plants is a well-known phenomenon which poses major problem in crop productivity in places where vast majority of land plants are affected by salt. In this report, studies were carried out to reveal the effect of salt injury on the cell division pattern in roots and the role of myo-inositol in preventing the salt-induced ion disequilibrium on the chromosome and DNA degradation in roots. Present study revealed induction of various chromosomal abnormalities on the root tip mitotic cells of Allium cepa by treatment with different concentrations of NaCl (0-500 mM) for 24 h as also the amelioration of such effect by prior treatment of the roots with different concentration of myo-inositol (0-300 mM). Results showed that a narrow albeit definite range of extracellular myo-inositol (100-150 mM) is effective in preventing internucleosomal fragmentation which is the early response in roots under salt stress. Transgenic tobacco plants overexpressing Oryza (OsINO1) as well as Porteresia (PcINO1) cytosolic L: -myo-inositol-1-phosphate synthase coding genes can withstand and retain their chromosomal and DNA integrity in 100 mM NaCl solution and can subsequently prevent DNA fragmentation, caused by intracellular endonuclease activity at this salt concentration.

  2. Lower "N"-Acetyl-Aspartate Levels in Prefrontal Cortices in Pediatric Bipolar Disorder: A (Superscript 1]H Magnetic Resonance Spectroscopy Study

    ERIC Educational Resources Information Center

    Caetano, Sheila C.; Olvera, Rene L.; Hatch, John P.; Sanches, Marsal; Chen, Hua Hsuan; Nicoletti, Mark; Stanley, Jeffrey A.; Fonseca, Manoela; Hunter, Kristina; Lafer, Beny; Pliszka, Steven R.; Soares, Jair C.

    2011-01-01

    Objective: The few studies applying single-voxel [superscript 1]H spectroscopy in children and adolescents with bipolar disorder (BD) have reported low "N"-acetyl-aspartate (NAA) levels in the dorsolateral prefrontal cortex (DLPFC), and high myo-inositol/phosphocreatine plus creatine (PCr+Cr) ratios in the anterior cingulate. The aim of this study…

  3. New secondary metabolites isolated from dondonae viscosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bioassay guided fractionation and chemical investigation of the ethanolic extract of the aerial parts of Dodonaea viscosa Linn. from Egypt, resulted in the isolation and identification of three new compounds, including two new clerodane diterpenoids and a new myo-inositol derivative, along with nine...

  4. Barley (Hordeum vulgare L.) inositol monophosphatase: gene structure and enzyme characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The de novo synthesis of myo-inositol (Ins) is catalyzed by two enzymatic activities; Ins(3)P1 synthase (MIPS; EC. 5.5.1.4) and Ins monophosphatase (IMPase; EC 3.1.3.25). The barley IMP-1 gene and gene products were studied to facilitate research into the regulation of Ins synthesis and supply. In m...

  5. 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.

  6. GC-MS metabolomic differentiation of selected citrus varieties with different sensitivity to citrus huanglongbing.

    PubMed

    Cevallos-Cevallos, Juan M; Futch, David B; Shilts, Turksen; Folimonova, Svetlana Y; Reyes-De-Corcuera, José I

    2012-04-01

    Huanglongbing (HLB) is the most destructive disease of citrus worldwide. The rapid identification of tolerant varieties is considered a critical step towards controlling HLB. GC-MS metabolite profiles were used to differentiate HLB-tolerant citrus varieties 'Poncirus trifoliata' (TR) and 'Carrizo citrange' (CAR) from HLB-sensitive varieties 'Madam Vinous sweet orange' (MV) and 'Duncan' grapefruit (DG). PCR analyses revealed that MV was the most sensitive variety followed by DG and the tolerant varieties CAR and TR. Metabolomic multivariate analysis allowed classification of the cultivars in apparent agreement with PCR results. Higher levels of the amino acids l-proline, l-serine, and l-aspartic acid, as well as the organic acids butanedioic and tetradecanoic acid, and accumulation of galactose in healthy plants were characteristic of the most sensitive variety MV when compared to all other varieties. Only galactose was significantly higher in DG when compared to the tolerant varieties TR and CAR. The tolerant varieties showed higher levels of l-glycine and mannose when compared to sensitive varieties MV and DG. Profiling of the sensitive varieties MV and DG over a 20-week period after inoculation of those with the HLB-containing material revealed strong responses of metabolites to HLB infection that differed from the response of the tolerant varieties. Significant changes of l-threonine level in the leaves from old mature flushes and l-serine, l-threonine, scyllo-inositol, hexadecanoic acid, and mannose in the leaves from young developing flushes were observed in MV. Significant changes in myo-inositol in old flushes and l-proline, indole, and xylose in new flushes were observed in DG.

  7. 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.

  8. Functional Characterization of Pneumocystis carinii Inositol Transporter 1

    PubMed Central

    Collins, Margaret S.; Sesterhenn, Thomas; Porollo, Aleksey; Vadukoot, Anish Kizhakkekkara; Merino, Edward J.

    2016-01-01

    ABSTRACT Fungi in the genus Pneumocystis live in the lungs of mammals, where they can cause a fatal pneumonia (PCP [Pneumocystis pneumonia]) in hosts with compromised immune systems. The absence of a continuous in vitro culture system for any species of Pneumocystis has led to limited understanding of these fungi, especially for the discovery of new therapies. We recently reported that Pneumocystis carinii, Pneumocystis murina, and most significantly, Pneumocystis jirovecii lack both enzymes necessary for myo-inositol biosynthesis but contain genes with homologies to fungal myo-inositol transporters. Since myo-inositol is essential for eukaryotic viability, the primary transporter, ITR1, was functionally and structurally characterized in P. carinii. The predicted structure of P. carinii ITR1 (PcITR1) contained 12 transmembrane alpha-helices with intracellular C and N termini, consistent with other inositol transporters. The apparent Km was 0.94 ± 0.08 (mean ± standard deviation), suggesting that myo-inositol transport in P. carinii is likely through a low-affinity, highly selective transport system, as no other sugars or inositol stereoisomers were significant competitive inhibitors. Glucose transport was shown to use a different transport system. The myo-inositol transport was distinct from mammalian transporters, as it was not sodium dependent and was cytochalasin B resistant. Inositol transport in these fungi offers an attractive new drug target because of the reliance of the fungi on its transport, clear differences between the mammalian and fungal transporters, and the ability of the host to both synthesize and transport this critical nutrient, predicting low toxicity of potential inhibitors to the fungal transporter. PMID:27965450

  9. Role of an Expanded Inositol Transporter Repertoire in Cryptococcus neoformans Sexual Reproduction and Virulence

    PubMed Central

    Xue, Chaoyang; Liu, Tongbao; Chen, Lydia; Li, Wenjun; Liu, Iris; Kronstad, James W.; Seyfang, Andreas; Heitman, Joseph

    2010-01-01

    ABSTRACT Cryptococcus neoformans and Cryptococcus gattii are globally distributed human fungal pathogens and the leading causes of fungal meningitis. Recent studies reveal that myo-inositol is an important factor for fungal sexual reproduction. That C. neoformans can utilize myo-inositol as a sole carbon source and the existence of abundant inositol in the human central nervous system suggest that inositol is important for Cryptococcus development and virulence. In accord with this central importance of inositol, an expanded myo-inositol transporter (ITR) gene family has been identified in Cryptococcus. This gene family contains two phylogenetically distinct groups, with a total of 10 or more members in C. neoformans and at least six members in the sibling species C. gattii. These inositol transporter genes are differentially expressed under inositol-inducing conditions based on quantitative real-time PCR analyses. Expression of ITR genes in a Saccharomyces cerevisiae itr1 itr2 mutant lacking inositol transport can complement the slow-growth phenotype of this strain, confirming that ITR genes are bona fide inositol transporters. Gene mutagenesis studies reveal that the Itr1 and Itr1A transporters are important for myo-inositol stimulation of mating and that functional redundancies among the myo-inositol transporters likely exist. Deletion of the inositol 1-phosphate synthase gene INO1 in an itr1 or itr1a mutant background compromised virulence in a murine inhalation model, indicating the importance of inositol sensing and acquisition for fungal infectivity. Our study provides a platform for further understanding the roles of inositol in fungal physiology and virulence. PMID:20689743

  10. 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.

  11. 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.

  12. 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…

  13. Osmoadaptative Strategy and Its Molecular Signature in Obligately Halophilic Heterotrophic Protists

    PubMed Central

    Harding, Tommy; Brown, Matthew W.; Simpson, Alastair G.B.; Roger, Andrew J.

    2016-01-01

    Halophilic microbes living in hypersaline environments must counteract the detrimental effects of low water activity and salt interference. Some halophilic prokaryotes equilibrate their intracellular osmotic strength with the extracellular milieu by importing inorganic solutes, mainly potassium. These “salt-in” organisms characteristically have proteins that are highly enriched with acidic and hydrophilic residues. In contrast, “salt-out” halophiles accumulate large amounts of organic solutes like amino acids, sugars and polyols, and lack a strong signature of halophilicity in the amino acid composition of cytoplasmic proteins. Studies to date have examined halophilic prokaryotes, yeasts, or algae, thus virtually nothing is known about the molecular adaptations of the other eukaryotic microbes, that is, heterotrophic protists (protozoa), that also thrive in hypersaline habitats. We conducted transcriptomic investigations to unravel the molecular adaptations of two obligately halophilic protists, Halocafeteria seosinensis and Pharyngomonas kirbyi. Their predicted cytoplasmic proteomes showed increased hydrophilicity compared with marine protists. Furthermore, analysis of reconstructed ancestral sequences suggested that, relative to mesophiles, proteins in halophilic protists have undergone fewer substitutions from hydrophilic to hydrophobic residues since divergence from their closest relatives. These results suggest that these halophilic protists have a higher intracellular salt content than marine protists. However, absence of the acidic signature of salt-in microbes suggests that Haloc. seosinensis and P. kirbyi utilize organic osmolytes to maintain osmotic equilibrium. We detected increased expression of enzymes involved in synthesis and transport of organic osmolytes, namely hydroxyectoine and myo-inositol, at maximal salt concentration for growth in Haloc. seosinensis, suggesting possible candidates for these inferred organic osmolytes. PMID:27412608

  14. Metabolic profiling reveals that PNPLA3 induces widespread effects on metabolism beyond triacylglycerol remodeling in Huh-7 hepatoma cells

    PubMed Central

    Min, Hae-Ki; Sookoian, Silvia; Pirola, Carlos J.; Cheng, Jianfeng; Mirshahi, Faridoddin

    2014-01-01

    PNPLA3 was recently associated with the susceptibility to nonalcoholic fatty liver disease, a common cause of chronic liver disease characterized by abnormal triglyceride accumulation. Although it is established that PNPLA3 has both triacylglycerol lipase and acylglycerol O-acyltransferase activities, is still unknown whether the gene has any additional role in the modulation of the human liver metabolome. To uncover the functional role of PNPLA3 on liver metabolism, we performed high-throughput metabolic profiling of PNPLA3 siRNA-silencing and overexpression of wild-type and mutant Ile148Met variants (isoleucine/methionine substitution at codon 148) in Huh-7 cells. Metabolomic analysis was performed by using GC/MS and LC/MS platforms. Silencing of PNPLA3 was associated with a global perturbation of Huh-7 hepatoma cells that resembled a catabolic response associated with protein breakdown. A significant decrease in amino- and γ-glutamyl-amino acids and dipeptides and a significant increase in cysteine sulfinic acid, myo-inositol, lysolipids, sphingolipids, and polyunsaturated fatty acids were observed. Overexpression of the PNPLA3 Met148 variant mirrored many of the metabolic changes observed during gene silencing, but in the opposite direction. These findings were replicated by the exploration of canonical pathways associated with PNPLA3 silencing and Met148 overexpression. Overexpression of the PNPLA3 Met148 variant was associated with a 1.75-fold increase in lactic acid, suggesting a shift to anaerobic metabolism and mitochondrial dysfunction. Together, these results suggest a critical role of PNPLA3 in the modulation of liver metabolism beyond its classical participation in triacylglycerol remodeling. PMID:24763554

  15. Evidence for carboxyl-terminal processing and glycolipid-anchoring of human carcinoembryonic antigen.

    PubMed

    Takami, N; Misumi, Y; Kuroki, M; Matsuoka, Y; Ikehara, Y

    1988-09-05

    We have investigated the post-translational modification of carcinoembryonic antigen (CEA) for membrane-anchoring in QGP-1 cells derived from a human pancreatic carcinoma. Pulse-chase experiments with [3H]leucine demonstrated that CEA was initially synthesized as a precursor form with Mr 150,000 having N-linked high-mannose-type oligosaccharides, which was then converted to a mature form with Mr 200,000 containing the complex type sugar chains. The mature protein thus labeled was found to be released from the cell surface by treatment with phosphatidylinositol-specific phospholipase C, suggesting that CEA is a phosphatidylinositol-linked membrane protein. This was confirmed by metabolic incorporation into CEA of 3H-labeled compounds such as ethanolamine, myo-inositol, palmitic acid, and stearic acid. The 3H-labeled fatty acids incorporated were specifically removed from the protein by nitrous acid deamination as well as by phosphatidylinositol-specific phospholipase C treatment. Since the available cDNA sequence predicts that CEA contains a single methionine residue only in its carboxyl-terminal hydrophobic domain, processing of the carboxyl terminus was examined by pulse-chase experiments with [35S]methionine. It was found that CEA with Mr 150,000 was initially labeled with [35S]methionine but its radioactivity was immediately lost with chase. Taken together, these results suggest that CEA is anchored to the membrane by simultaneously occurring proteolysis of the carboxyl terminus and replacement by the glycophospholipid immediately after the synthesis.

  16. An insight into the metabolic responses of ultra-small superparamagnetic particles of iron oxide using metabonomic analysis of biofluids

    NASA Astrophysics Data System (ADS)

    Feng, Jianghua; Liu, Huili; Zhang, Limin; Bhakoo, Kishore; Lu, Lehui

    2010-10-01

    Ultra-small superparamagnetic particles of iron oxides (USPIO) have been developed as intravenous organ/tissue-targeted contrast agents to improve magnetic resonance imaging (MRI) in vivo. However, their potential toxicity and effects on metabolism have attracted particular attention. In the present study, uncoated and dextran-coated USPIO were investigated by analyzing both rat urine and plasma metabonomes using high-resolution NMR-based metabonomic analysis in combination with multivariate statistical analysis. The wealth of information gathered on the metabolic profiles from rat urine and plasma has revealed subtle metabolic changes in response to USPIO administration. The metabolic changes include the elevation of urinary α-hydroxy-n-valerate, o- and p-HPA, PAG, nicotinate and hippurate accompanied by decreases in the levels of urinary α-ketoglutarate, succinate, citrate, N-methylnicotinamide, NAG, DMA, allantoin and acetate following USPIO administration. The changes associated with USPIO administration included a gradual increase in plasma glucose, N-acetyl glycoprotein, saturated fatty acid, citrate, succinate, acetate, GPC, ketone bodies (β-hydroxybutyrate, acetone and acetoacetate) and individual amino acids, such as phenylalanine, lysine, isoleucine, glycine, glutamine and glutamate and a gradual decrease of myo-inositol, unsaturated fatty acid and triacylglycerol. Hence USPIO administration effects are reflected in changes in a number of metabolic pathways including energy, lipid, glucose and amino acid metabolism. The size- and surface chemistry-dependent metabolic responses and possible toxicity were observed using NMR analysis of biofluids. These changes may be attributed to the disturbances of hepatic, renal and cardiac functions following USPIO administrations. The potential biotoxicity can be derived from metabonomic analysis and serum biochemistry analysis. Metabonomic strategy offers a promising approach for the detection of subtle

  17. MIPS: a calmodulin-binding protein of Gracilaria lemaneiformis under heat shock.

    PubMed

    Zhang, Xuan; Zhou, Huiyue; Zang, Xiaonan; Gong, Le; Sun, Hengyi; Zhang, Xuecheng

    2014-08-01

    To study the Ca(2+)/Calmodulin (CaM) signal transduction pathway of Gracilaria lemaneiformis under heat stress, myo-inositol-1-phosphate synthase (MIPS), a calmodulin-binding protein, was isolated using the yeast two-hybrid system. cDNA and DNA sequences of mips were cloned from G. lemaneiformis by using 5'RACE and genome walking procedures. The MIPS DNA sequence was 2,067 nucleotides long, containing an open reading frame (ORF) of 1,623 nucleotides with no intron. The mips ORF was predicted to encode 540 amino acids, which included the conserved MIPS domain and was 61-67 % similar to that of other species. After analyzing the amino acid sequence of MIPS, the CaM-Binding Domain (CaMBD) was inferred to be at a site spanning from amino acid 212 to amino acid 236. The yeast two-hybrid results proved that MIPS can interact with CaM and that MIPS is a type of calmodulin-binding protein. Next, the expression of CaM and MIPS in wild-type G. lemaneiformis and a heat-tolerant G. lemaneiformis cultivar, "981," were analyzed using real-time PCR under a heat shock of 32 °C. The expression level displayed a cyclical upward trend. Compared with wild type, the CaM expression levels of cultivar 981 were higher, which might directly relate to its resistance to high temperatures. This paper indicates that MIPS and CaM may play important roles in the high-temperature resistance of G. lemaneiformis.

  18. 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.

  19. 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

  20. 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 ...

  1. 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 ...

  2. 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 ...

  3. 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 ...

  4. 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 ...

  5. 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 ...

  6. 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 ...

  7. 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 , ...

  8. 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 ...

  9. 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 ...

  10. 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 ...

  11. 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, ...

  12. 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 ...

  13. 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.

  14. 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.

  15. 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.

  16. 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...

  17. 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)

  18. 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.…

  19. 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)…

  20. 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…

  1. 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 ...

  2. [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…

  3. Synthesis of unsaturated phosphatidylinositol 4-phosphates and the effects of substrate unsaturation on SopB phosphatase activity.

    PubMed

    Furse, Samuel; Mak, LokHang; Tate, Edward W; Templer, Richard H; Ces, Oscar; Woscholski, Rüdiger; Gaffney, Piers R J

    2015-02-21

    In this paper evidence is presented that the fatty acid component of an inositide substrate affects the kinetic parameters of the lipid phosphatase Salmonella Outer Protein B (SopB). A succinct route was used to prepare the naturally occurring enantiomer of phosphatidylinositol 4-phosphate (PI-4-P) with saturated, as well as singly, triply and quadruply unsaturated, fatty acid esters, in four stages: (1) The enantiomers of 2,3:5,6-O-dicyclohexylidene-myo-inositol were resolved by crystallisation of their di(acetylmandelate) diastereoisomers. (2) The resulting diol was phosphorylated regio-selectively exclusively on the 1-O using the new reagent tri(2-cyanoethyl)phosphite. (3) With the 4-OH still unprotected, the glyceride was coupled using phosphate tri-ester methodology. (4) A final phosphorylation of the 4-O, followed by global deprotection under basic then acidic conditions, provided PI-4-P bearing a range of sn-1-stearoyl, sn-2-stearoyl, -oleoyl, -γ-linolenoyl and arachidonoyl, glycerides. Enzymological studies showed that the introduction of cis-unsaturated bonds has a measurable influence on the activity (relative Vmax) of SopB. Mono-unsaturated PI-4-P exhibited a five-fold higher activity, with a two-fold higher KM, over the saturated substrate, when presented in DOPC vesicles. Poly-unsaturated PI-4-P showed little further change with respect to the singly unsaturated species. This result, coupled with our previous report that saturated PI-4-P has much higher stored curvature elastic stress than PI, supports the hypothesis that the activity of inositide phosphatase SopB has a physical role in vivo.

  4. Reduction of inositol (1,4,5)-trisphosphate affects the overall phosphoinositol pathway and leads to modifications in light signalling and secondary metabolism in tomato plants.

    PubMed

    Alimohammadi, Mohammad; de Silva, Kanishka; Ballu, Clarisse; Ali, Nawab; Khodakovskaya, Mariya V

    2012-01-01

    The phosphoinositol pathway is one of the major eukaryotic signalling pathways. The metabolite of the phosphoinositol pathway, inositol- (1,4,5) trisphosphate (InsP(3)), is a regulator of plant responses to a wide variety of stresses, including light, drought, cold, and salinity. It was found that the expression of InsP 5-ptase, the enzyme that hydrolyses InsP(3), also dramatically affects the levels of inositol phosphate metabolites and the secondary metabolites in transgenic tomato plants. Tomato plants expressing InsP 5-ptase exhibited a reduction in the levels of several important inositol phosphates, including InsP(1), InsP(2), InsP(3), and InsP(4). Reduced levels of inositol phosphates accompanied an increase in the accumulation of phenylpropanoids (rutin, chlorogenic acid) and ascorbic acid (vitamin C) in the transgenic fruits of tomato plants. The enhanced accumulation of these metabolites in transgenic tomato plants was in direct correspondence with the observed up-regulation of the genes that express the key enzymes of ascorbic acid metabolism (myo-inositol oxygenase, MIOX; L-galactono-γ-lactone dehydrogenase, GLDH) and phenylpropanoid metabolism (chalcone synthase, CHS1; cinnamoyl-CoA shikimate/quinate transferase, HCT). To understand the molecular links between the activation of different branches of plant metabolism and InsP(3) reduction in tomato fruits, the expression of transcription factors known to be involved in light signalling was analysed by real-time RT-PCR. The expression of LeHY5, SIMYB12, and LeELIP was found to be higher in fruits expressing InsP 5-ptase. These results suggest possible interconnections between phosphoinositol metabolism, light signalling, and secondary metabolism in plants. Our study also revealed the biotechnological potential for the genetic improvement of crop plants by the manipulation of the phosphoinositol pathway.

  5. Recognition of a Nocardia transvalensis complex by resistance to aminoglycosides, including amikacin, and PCR-restriction fragment length polymorphism analysis.

    PubMed

    Wilson, R W; Steingrube, V A; Brown, B A; Blacklock, Z; Jost, K C; McNabb, A; Colby, W D; Biehle, J R; Gibson, J L; Wallace, R J

    1997-09-01

    Amikacin resistance, rare among nocardiae, was observed in 58 clinical isolates of nocardiae. All of these isolates hydrolyzed hypoxanthine, and 75 to 100% utilized citrate, D-galactose, and D-trehalose as sole carbon sources. Based on utilization of I-erythritol, D-glucitol, i-myo-inositol, D-mannitol, and ribitol and susceptibility to amoxicillin-clavulanic acid, the 58 isolates were separable into four groups. One group was negative for I-erythritol and ribitol and included all the isolates belonging to Nocardia asteroides complex antibiogram type IV. The remaining three groups were positive for I-erythritol and ribitol and were grouped within Nocardia transvalensis. The group that included the type strain was designated N. transvalensis sensu stricto, and the other two groups were designated new taxons 1 and 2. PCR-restriction fragment length polymorphism (RFLP) analysis of a 439-bp segment of the 65-kDa heat shock protein gene with XhoI and HinfI produced identical patterns for 53 (91%) and 58 (100%) isolates, respectively, and differentiated them from all other Nocardia taxa. NarI- and HaeIII-derived RFLP patterns clearly differentiated each of the four biochemically defined taxa. These four groups were also distinguishable by using the chromogenic substrates in Dade MicroScan test panels. By high-performance liquid chromatography, these isolates exhibited the same unique mycolic acid-ester elution patterns that differed from those of all other clinically significant nocardiae. Gas-liquid chromatographic analysis of fatty acids also produced similar patterns for all isolates that distinguished them from all other Nocardia taxa, but did not differentiate the four taxa within the complex. We propose the designation N. transvalensis complex for these four groups of nocardiae, pending further genetic evaluation.

  6. (1)H NMR-based metabolomics reveals neurochemical alterations in the brain of adolescent rats following acute methylphenidate administration.

    PubMed

    Quansah, Emmanuel; Ruiz-Rodado, Victor; Grootveld, Martin; Probert, Fay; Zetterström, Tyra S C

    2017-03-06

    The psychostimulant methylphenidate (MPH) is increasingly used in the treatment of attention deficit hyperactivity disorder (ADHD). While there is little evidence for common brain pathology in ADHD, some studies suggest a right hemisphere dysfunction among people diagnosed with the condition. However, in spite of the high usage of MPH in children and adolescents, its mechanism of action is poorly understood. Given that MPH blocks the neuronal transporters for dopamine and noradrenaline, most research into the effects of MPH on the brain has largely focused on these two monoamine neurotransmitter systems. Interestingly, recent studies have demonstrated metabolic changes in the brain of ADHD patients, but the impact of MPH on endogenous brain metabolites remains unclear. In this study, a proton nuclear magnetic resonance ((1)H NMR)-based metabolomics approach was employed to investigate the effects of MPH on brain biomolecules. Adolescent male Sprague Dawley rats were injected intraperitoneally with MPH (5.0 mg/kg) or saline (1.0 ml/kg), and cerebral extracts from the left and right hemispheres were analysed. A total of 22 variables (representing 13 distinct metabolites) were significantly increased in the MPH-treated samples relative to the saline-treated controls. The upregulated metabolites included: amino acid neurotransmitters such as GABA, glutamate and aspartate; large neutral amino acids (LNAA), including the aromatic amino acids (AAA) tyrosine and phenylalanine, both of which are involved in the metabolism of dopamine and noradrenaline; and metabolites associated with energy and cell membrane dynamics, such as creatine and myo-inositol. No significant differences in metabolite concentrations were found between the left and right cerebral hemispheres. These findings provide new insights into the mechanisms of action of the anti-ADHD drug MPH.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. [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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Ascorbate Alleviates Fe Deficiency-Induced Stress in Cotton (Gossypium hirsutum) by Modulating ABA Levels.

    PubMed

    Guo, Kai; Tu, Lili; Wang, Pengcheng; Du, Xueqiong; Ye, Shue; Luo, Ming; Zhang, Xianlong

    2016-01-01

    Fe deficiency causes significant losses to crop productivity and quality. To understand better the mechanisms of plant responses to Fe deficiency, we used an in vitro cotton ovule culture system. We found that Fe deficiency suppressed the development of ovules and fibers, and led to tissue browning. RNA-seq analysis showed that the myo-inositol and galacturonic acid pathways were activated and cytosolic APX (ascorbate peroxidase) was suppressed in Fe-deficient treated fibers, which increased ASC (ascorbate) concentrations to prevent tissue browning. Suppression of cytosolic APX by RNAi in cotton increased ASC contents and delayed tissue browning by maintaining ferric reduction activity under Fe-deficient conditions. Meanwhile, APX RNAi line also exhibited the activation of expression of iron-regulated transporter (IRT1) and ferric reductase-oxidase2 (FRO2) to adapt to Fe deficiency. Abscisic acid (ABA) levels were significantly decreased in Fe-deficient treated ovules and fibers, while the upregulated expression of ABA biosynthesis genes and suppression of ABA degradation genes in Fe-deficient ovules slowed down the decreased of ABA in cytosolic APX suppressed lines to delay the tissue browning. Moreover, the application of ABA in Fe-deficient medium suppressed the development of tissue browning and completely restored the ferric reduction activity. In addition, ABA 8'-hydroxylase gene (GhABAH1) overexpressed cotton has a decreased level of ABA and shows more sensitivity to Fe deficiency. Based on the results, we speculate that ASC could improve the tolerance to Fe deficiency through activating Fe uptake and maintaining ABA levels in cotton ovules and fibers, which in turn reduces symptom formation.