Sample records for conserved wobble uridine

  1. Loss of Anticodon Wobble Uridine Modifications Affects tRNALys Function and Protein Levels in Saccharomyces cerevisiae

    PubMed Central

    Klassen, Roland; Grunewald, Pia; Thüring, Kathrin L.; Eichler, Christian; Helm, Mark; Schaffrath, Raffael

    2015-01-01

    In eukaryotes, wobble uridines in the anticodons of tRNALys UUU, tRNAGlu UUC and tRNAGln UUG are modified to 5-methoxy-carbonyl-methyl-2-thio-uridine (mcm5s2U). While mutations in subunits of the Elongator complex (Elp1-Elp6), which disable mcm5 side chain formation, or removal of components of the thiolation pathway (Ncs2/Ncs6, Urm1, Uba4) are individually tolerated, the combination of both modification defects has been reported to have lethal effects on Saccharomyces cerevisiae. Contrary to such absolute requirement of mcm5s2U for viability, we demonstrate here that in the S. cerevisiae S288C-derived background, both pathways can be simultaneously inactivated, resulting in combined loss of tRNA anticodon modifications (mcm5U and s2U) without a lethal effect. However, an elp3 disruption strain displays synthetic sick interaction and synergistic temperature sensitivity when combined with either uba4 or urm1 mutations, suggesting major translational defects in the absence of mcm5s2U modifications. Consistent with this notion, we find cellular protein levels drastically decreased in an elp3uba4 double mutant and show that this effect as well as growth phenotypes can be partially rescued by excess of tRNALys UUU. These results may indicate a global translational or protein homeostasis defect in cells simultaneously lacking mcm5 and s2 wobble uridine modification that could account for growth impairment and mainly originates from tRNALys UUU hypomodification and malfunction. PMID:25747122

  2. Loss of anticodon wobble uridine modifications affects tRNA(Lys) function and protein levels in Saccharomyces cerevisiae.

    PubMed

    Klassen, Roland; Grunewald, Pia; Thüring, Kathrin L; Eichler, Christian; Helm, Mark; Schaffrath, Raffael

    2015-01-01

    In eukaryotes, wobble uridines in the anticodons of tRNA(Lys)UUU, tRNA(Glu)UUC and tRNA(Gln)UUG are modified to 5-methoxy-carbonyl-methyl-2-thio-uridine (mcm5s2U). While mutations in subunits of the Elongator complex (Elp1-Elp6), which disable mcm5 side chain formation, or removal of components of the thiolation pathway (Ncs2/Ncs6, Urm1, Uba4) are individually tolerated, the combination of both modification defects has been reported to have lethal effects on Saccharomyces cerevisiae. Contrary to such absolute requirement of mcm5s2U for viability, we demonstrate here that in the S. cerevisiae S288C-derived background, both pathways can be simultaneously inactivated, resulting in combined loss of tRNA anticodon modifications (mcm5U and s2U) without a lethal effect. However, an elp3 disruption strain displays synthetic sick interaction and synergistic temperature sensitivity when combined with either uba4 or urm1 mutations, suggesting major translational defects in the absence of mcm5s2U modifications. Consistent with this notion, we find cellular protein levels drastically decreased in an elp3uba4 double mutant and show that this effect as well as growth phenotypes can be partially rescued by excess of tRNA(Lys)UUU. These results may indicate a global translational or protein homeostasis defect in cells simultaneously lacking mcm5 and s2 wobble uridine modification that could account for growth impairment and mainly originates from tRNA(Lys)UUU hypomodification and malfunction.

  3. A conserved modified wobble nucleoside (mcm5s2U) in lysyl-tRNA is required for viability in yeast

    PubMed Central

    Björk, Glenn R.; Huang, Bo; Persson, Olof P.; Byström, Anders S.

    2007-01-01

    Transfer RNAs specific for Gln, Lys, and Glu from all organisms (except Mycoplasma) and organelles have a 2-thiouridine derivative (xm5s2U) as wobble nucleoside. These tRNAs read the A- and G-ending codons in the split codon boxes His/Gln, Asn/Lys, and Asp/Glu. In eukaryotic cytoplasmic tRNAs the conserved constituent (xm5-) in position 5 of uridine is 5-methoxycarbonylmethyl (mcm5). A protein (Tuc1p) from yeast resembling the bacterial protein TtcA, which is required for the synthesis of 2-thiocytidine in position 32 of the tRNA, was shown instead to be required for the synthesis of 2-thiouridine in the wobble position (position 34). Apparently, an ancient member of the TtcA family has evolved to thiolate U34 in tRNAs of organisms from the domains Eukarya and Archaea. Deletion of the TUC1 gene together with a deletion of the ELP3 gene, which results in the lack of the mcm5 side chain, removes all modifications from the wobble uridine derivatives of the cytoplasmic tRNAs specific for Gln, Lys, and Glu, and is lethal to the cell. Since excess of the unmodified form of these three tRNAs rescued the double mutant elp3 tuc1, the primary function of mcm5s2U34 seems to be to improve the efficiency to read the cognate codons rather than to prevent mis-sense errors. Surprisingly, overexpression of the mcm5s2U-lacking tRNALys alone was sufficient to restore viability of the double mutant. PMID:17592039

  4. Evolutionarily conserved proteins MnmE and GidA catalyze the formation of two methyluridine derivatives at tRNA wobble positions

    PubMed Central

    Moukadiri, Ismaïl; Prado, Silvia; Piera, Julio; Velázquez-Campoy, Adrián; Björk, Glenn R.; Armengod, M.-Eugenia

    2009-01-01

    The wobble uridine of certain bacterial and mitochondrial tRNAs is modified, at position 5, through an unknown reaction pathway that utilizes the evolutionarily conserved MnmE and GidA proteins. The resulting modification (a methyluridine derivative) plays a critical role in decoding NNG/A codons and reading frame maintenance during mRNA translation. The lack of this tRNA modification produces a pleiotropic phenotype in bacteria and has been associated with mitochondrial encephalomyopathies in humans. In this work, we use in vitro and in vivo approaches to characterize the enzymatic pathway controlled by the Escherichia coli MnmE•GidA complex. Surprisingly, this complex catalyzes two different GTP- and FAD-dependent reactions, which produce 5-aminomethyluridine and 5-carboxymethylamino-methyluridine using ammonium and glycine, respectively, as substrates. In both reactions, methylene-tetrahydrofolate is the most probable source to form the C5-methylene moiety, whereas NADH is dispensable in vitro unless FAD levels are limiting. Our results allow us to reformulate the bacterial MnmE•GidA dependent pathway and propose a novel mechanism for the modification reactions performed by the MnmE and GidA family proteins. PMID:19767610

  5. Does Venus wobble

    NASA Technical Reports Server (NTRS)

    Yoder, C. F.; Ward, W. R.

    1979-01-01

    The free wobble damping time for Venus due to solar tides and rotational flexing is found to be approximately 700,000 times Q sub omega years, where Q sub omega is the dissipation function associated with the wobble frequency. The slow spin and expected small (nonhydrostatic) J2 predict a very long wobble period of about 100,000 years. As a result, a simple scaling of the earth's Chandler wobble excitation rate to that of Venus suggests that an appreciable wobble could exist. Detection (or lack thereof) of a free wobble may thus place constraints on the dynamic activity (e.g., mantle convection, Venusquakes, etc.) of the Venus interior.

  6. Milankovitch wobble?

    NASA Astrophysics Data System (ADS)

    Mitchell, R. N.; Thissen, C.; Kirschvink, J. L.; Schrag, D. P.; Montanari, A.; Coccioni, R.; Slotznick, S. P.; Yamazaki, T.; Penserini, B. D.; Abrahams, J. N. H.; Cruz-Heredia, M.; Evans, D. A.

    2015-12-01

    High-resolution paleomagnetism of Cretaceous-aged limestone in Italy reveals evidence for a previously unrecognized ~10˚ directional variation, or "wobble", of either the geographic or magnetic pole on a 106-year, "Milankovitch" time scale. Ten ~1 million year (Myr) wobbles of magnetic inclination can be identified and correlated across Italy from 87-74 Myr ago, potentially refining the global polarity time scale and seafloor spreading rates. Milankovitch wobble is an omnipresent geophysical process that represents, irrespective of its mechanism, a new chronometer for age calibration with paleomagnetism. If Milankovitch wobble is interpreted as a geomagnetic artifact—the long-considered but still unproven idea that astronomical variations influence the geodynamo—the geocentric-axial dipole hypothesis would only be viable when averaged over time scales 100 times greater than currently thought, making present-day geocentricity largely coincidental. If interpreted as true geographic change, Milankovitch wobble implies an unrecognized, rapid time scale (~10˚ Myr-1) of true polar wander, possibly due to ice sheet dynamics driven by the 1.2 Myr modulation of Earth's rotational obliquity. Stable isotope data co-vary with the Milankovitch wobble, possibly favoring the polar wander mechanism that predicts rapid environmental change where the geomagnetic artifact hypothesis does not.

  7. Archaeal Tuc1/Ncs6 Homolog Required for Wobble Uridine tRNA Thiolation Is Associated with Ubiquitin-Proteasome, Translation, and RNA Processing System Homologs

    PubMed Central

    Chavarria, Nikita E.; Hwang, Sungmin; Cao, Shiyun; Fu, Xian; Holman, Mary; Elbanna, Dina; Rodriguez, Suzanne; Arrington, Deanna; Englert, Markus; Uthandi, Sivakumar; Söll, Dieter; Maupin-Furlow, Julie A.

    2014-01-01

    While cytoplasmic tRNA 2-thiolation protein 1 (Tuc1/Ncs6) and ubiquitin-related modifier-1 (Urm1) are important in the 2-thiolation of 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U) at wobble uridines of tRNAs in eukaryotes, the biocatalytic roles and properties of Ncs6/Tuc1 and its homologs are poorly understood. Here we present the first report of an Ncs6 homolog of archaea (NcsA of Haloferax volcanii) that is essential for maintaining cellular pools of thiolated tRNALys UUU and for growth at high temperature. When purified from Hfx. volcanii, NcsA was found to be modified at Lys204 by isopeptide linkage to polymeric chains of the ubiquitin-fold protein SAMP2. The ubiquitin-activating E1 enzyme homolog of archaea (UbaA) was required for this covalent modification. Non-covalent protein partners that specifically associated with NcsA were also identified including UbaA, SAMP2, proteasome activating nucleotidase (PAN)-A/1, translation elongation factor aEF-1α and a β-CASP ribonuclease homolog of the archaeal cleavage and polyadenylation specificity factor 1 family (aCPSF1). Together, our study reveals that NcsA is essential for growth at high temperature, required for formation of thiolated tRNALys UUU and intimately linked to homologs of ubiquitin-proteasome, translation and RNA processing systems. PMID:24906001

  8. Archaeal Tuc1/Ncs6 homolog required for wobble uridine tRNA thiolation is associated with ubiquitin-proteasome, translation, and RNA processing system homologs.

    PubMed

    Chavarria, Nikita E; Hwang, Sungmin; Cao, Shiyun; Fu, Xian; Holman, Mary; Elbanna, Dina; Rodriguez, Suzanne; Arrington, Deanna; Englert, Markus; Uthandi, Sivakumar; Söll, Dieter; Maupin-Furlow, Julie A

    2014-01-01

    While cytoplasmic tRNA 2-thiolation protein 1 (Tuc1/Ncs6) and ubiquitin-related modifier-1 (Urm1) are important in the 2-thiolation of 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U) at wobble uridines of tRNAs in eukaryotes, the biocatalytic roles and properties of Ncs6/Tuc1 and its homologs are poorly understood. Here we present the first report of an Ncs6 homolog of archaea (NcsA of Haloferax volcanii) that is essential for maintaining cellular pools of thiolated tRNA(Lys)UUU and for growth at high temperature. When purified from Hfx. volcanii, NcsA was found to be modified at Lys204 by isopeptide linkage to polymeric chains of the ubiquitin-fold protein SAMP2. The ubiquitin-activating E1 enzyme homolog of archaea (UbaA) was required for this covalent modification. Non-covalent protein partners that specifically associated with NcsA were also identified including UbaA, SAMP2, proteasome activating nucleotidase (PAN)-A/1, translation elongation factor aEF-1α and a β-CASP ribonuclease homolog of the archaeal cleavage and polyadenylation specificity factor 1 family (aCPSF1). Together, our study reveals that NcsA is essential for growth at high temperature, required for formation of thiolated tRNA(Lys)UUU and intimately linked to homologs of ubiquitin-proteasome, translation and RNA processing systems.

  9. Uridine Affects Liver Protein Glycosylation, Insulin Signaling, and Heme Biosynthesis

    PubMed Central

    Urasaki, Yasuyo; Pizzorno, Giuseppe; Le, Thuc T.

    2014-01-01

    Purines and pyrimidines are complementary bases of the genetic code. The roles of purines and their derivatives in cellular signal transduction and energy metabolism are well-known. In contrast, the roles of pyrimidines and their derivatives in cellular function remain poorly understood. In this study, the roles of uridine, a pyrimidine nucleoside, in liver metabolism are examined in mice. We report that short-term uridine administration in C57BL/6J mice increases liver protein glycosylation profiles, reduces phosphorylation level of insulin signaling proteins, and activates the HRI-eIF-2α-ATF4 heme-deficiency stress response pathway. Short-term uridine administration is also associated with reduced liver hemin level and reduced ability for insulin-stimulated blood glucose removal during an insulin tolerance test. Some of the short-term effects of exogenous uridine in C57BL/6J mice are conserved in transgenic UPase1 −/− mice with long-term elevation of endogenous uridine level. UPase1 −/− mice exhibit activation of the liver HRI-eIF-2α-ATF4 heme-deficiency stress response pathway. UPase1 −/− mice also exhibit impaired ability for insulin-stimulated blood glucose removal. However, other short-term effects of exogenous uridine in C57BL/6J mice are not conserved in UPase1 −/− mice. UPase1 −/− mice exhibit normal phosphorylation level of liver insulin signaling proteins and increased liver hemin concentration compared to untreated control C57BL/6J mice. Contrasting short-term and long-term consequences of uridine on liver metabolism suggest that uridine exerts transient effects and elicits adaptive responses. Taken together, our data support potential roles of pyrimidines and their derivatives in the regulation of liver metabolism. PMID:24918436

  10. The electrostatic characteristics of G·U wobble base pairs

    PubMed Central

    Xu, Darui; Landon, Theresa; Greenbaum, Nancy L.; Fenley, Marcia O.

    2007-01-01

    G·U wobble base pairs are the most common and highly conserved non-Watson–Crick base pairs in RNA. Previous surface maps imply uniformly negative electrostatic potential at the major groove of G·U wobble base pairs embedded in RNA helices, suitable for entrapment of cationic ligands. In this work, we have used a Poisson–Boltzmann approach to gain a more detailed and accurate characterization of the electrostatic profile. We found that the major groove edge of an isolated G·U wobble displays distinctly enhanced negativity compared with standard GC or AU base pairs; however, in the context of different helical motifs, the electrostatic pattern varies. G·U wobbles with distinct widening have similar major groove electrostatic potentials to their canonical counterparts, whereas those with minimal widening exhibit significantly enhanced electronegativity, ranging from 0.8 to 2.5 kT/e, depending upon structural features. We propose that the negativity at the major groove of G·U wobble base pairs is determined by the combined effect of the base atoms and the sugar-phosphate backbone, which is impacted by stacking pattern and groove width as a result of base sequence. These findings are significant in that they provide predictive power with respect to which G·U sites in RNA are most likely to bind cationic ligands. PMID:17526525

  11. Antiarrhythmic effect of uridine and uridine-5'-monophosphate in acute myocardial ischemia.

    PubMed

    Bul'on, V V; Krylova, I B; Selina, E N; Rodionova, O M; Evdokimova, N R; Sapronov, N S; Mironova, G D

    2014-10-01

    Experiments on rats with acute myocardial ischemia accompanied by early postocclusive arrhythmias have shown normalizing, energy-stabilizing, and antiarrhythmic effects of uridine and uridine-5'-monophosphate. The drugs decreased lactate and restored reserves of glycogen and creatine phosphate depleted by ischemia. Uridine and uridine-5'-monophosphate significantly decreased the severity of ventricular arrhythmias. Both drugs reduced the incidence and duration of fibrillation. Uridine -5'-monophosphate demonstrated most pronounced antifibrillatory effectiveness. We hypothesize that the antiarrhythmic effect of the drugs is determined by their capacity to activate energy metabolism.

  12. tRNA tKUUU, tQUUG, and tEUUC wobble position modifications fine-tune protein translation by promoting ribosome A-site binding.

    PubMed

    Rezgui, Vanessa Anissa Nathalie; Tyagi, Kshitiz; Ranjan, Namit; Konevega, Andrey L; Mittelstaet, Joerg; Rodnina, Marina V; Peter, Matthias; Pedrioli, Patrick G A

    2013-07-23

    tRNA modifications are crucial to ensure translation efficiency and fidelity. In eukaryotes, the URM1 and ELP pathways increase cellular resistance to various stress conditions, such as nutrient starvation and oxidative agents, by promoting thiolation and methoxycarbonylmethylation, respectively, of the wobble uridine of cytoplasmic (tK(UUU)), (tQ(UUG)), and (tE(UUC)). Although in vitro experiments have implicated these tRNA modifications in modulating wobbling capacity and translation efficiency, their exact in vivo biological roles remain largely unexplored. Using a combination of quantitative proteomics and codon-specific translation reporters, we find that translation of a specific gene subset enriched for AAA, CAA, and GAA codons is impaired in the absence of URM1- and ELP-dependent tRNA modifications. Moreover, in vitro experiments using native tRNAs demonstrate that both modifications enhance binding of tK(UUU) to the ribosomal A-site. Taken together, our data suggest that tRNA thiolation and methoxycarbonylmethylation regulate translation of genes with specific codon content.

  13. Uridine protects cortical neurons from glucose deprivation-induced death: possible role of uridine phosphorylase.

    PubMed

    Choi, Ji Woong; Shin, Chan Young; Choi, Min Sik; Yoon, Seo Young; Ryu, Jong Hoon; Lee, Jae-Chul; Kim, Won-Ki; El Kouni, Mahmoud H; Ko, Kwang Ho

    2008-06-01

    We previously reported that uridine blocked glucose deprivation-induced death of immunostimulated astrocytes by preserving ATP levels. Uridine phosphorylase (UPase), an enzyme catalyzing the reversible phosphorylation of uridine, was involved in this effect. Here, we tried to expand our previous findings by investigating the uridine effect on the brain and neurons using in vivo and in vitro ischemic injury models. Orally administrated uridine (50-200 mg/kg) reduced middle cerebral artery occlusion (1.5 h)/reperfusion (22 h)-induced infarct in mouse brain. Additionally, in the rat brain subjected to the same ischemic condition, UPase mRNA and protein levels were up-regulated. Next, we employed glucose deprivation-induced hypoglycemia in mixed cortical cultures of neurons and astrocytes as an in vitro model. Cells were deprived of glucose and, two hours later, supplemented with 20 mM glucose. Under this condition, a significant ATP loss followed by death was observed in neurons but not in astrocytes, which were blocked by treatment with uridine in a concentration-dependent manner. Inhibition of cellular uptake of uridine by S-(4-nitrobenzyl)-6-thioinosine blocked the uridine effect. Similar to our in vivo data, UPase expression was up-regulated by glucose deprivation in mRNA as well as protein levels. Additionally, 5-(phenylthio)acyclouridine, a specific inhibitor of UPase, prevented the uridine effect. Finally, the uridine effect was shown only in the presence of astrocytes. Taken together, the present study provides the first evidence that uridine protects neurons against ischemic insult-induced neuronal death, possibly through the action of UPase.

  14. X-ray structures of uridine phosphorylase from Vibrio cholerae in complexes with uridine, thymidine, uracil, thymine, and phosphate anion: Substrate specificity of bacterial uridine phosphorylases

    NASA Astrophysics Data System (ADS)

    Prokofev, I. I.; Lashkov, A. A.; Gabdulkhakov, A. G.; Balaev, V. V.; Seregina, T. A.; Mironov, A. S.; Betzel, C.; Mikhailov, A. M.

    2016-11-01

    In many types of human tumor cells and infectious agents, the demand for pyrimidine nitrogen bases increases during the development of the disease, thus increasing the role of the enzyme uridine phosphorylase in metabolic processes. The rational use of uridine phosphorylase and its ligands in pharmaceutical and biotechnology industries requires knowledge of the structural basis for the substrate specificity of the target enzyme. This paper summarizes the results of the systematic study of the three-dimensional structure of uridine phosphorylase from the pathogenic bacterium Vibrio cholerae in complexes with substrates of enzymatic reactions—uridine, phosphate anion, thymidine, uracil, and thymine. These data, supplemented with the results of molecular modeling, were used to consider in detail the structural basis for the substrate specificity of uridine phosphorylases. It was shown for the first time that the formation of a hydrogen-bond network between the 2'-hydroxy group of uridine and atoms of the active-site residues of uridine phosphorylase leads to conformational changes of the ribose moiety of uridine, resulting in an increase in the reactivity of uridine compared to thymidine. Since the binding of thymidine to residues of uridine phosphorylase causes a smaller local strain of the β-N1-glycosidic bond in this the substrate compared to the uridine molecule, the β-N1-glycosidic bond in thymidine is more stable and less reactive than that in uridine. It was shown for the first time that the phosphate anion, which is the second substrate bound at the active site, interacts simultaneously with the residues of the β5-strand and the β1-strand through hydrogen bonding, thus securing the gate loop in a conformation

  15. X-ray structures of uridine phosphorylase from Vibrio cholerae in complexes with uridine, thymidine, uracil, thymine, and phosphate anion: Substrate specificity of bacterial uridine phosphorylases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Prokofev, I. I.; Lashkov, A. A., E-mail: alashkov83@gmail.com; Gabdulkhakov, A. G.

    In many types of human tumor cells and infectious agents, the demand for pyrimidine nitrogen bases increases during the development of the disease, thus increasing the role of the enzyme uridine phosphorylase in metabolic processes. The rational use of uridine phosphorylase and its ligands in pharmaceutical and biotechnology industries requires knowledge of the structural basis for the substrate specificity of the target enzyme. This paper summarizes the results of the systematic study of the three-dimensional structure of uridine phosphorylase from the pathogenic bacterium Vibrio cholerae in complexes with substrates of enzymatic reactions—uridine, phosphate anion, thymidine, uracil, and thymine. These data,more » supplemented with the results of molecular modeling, were used to consider in detail the structural basis for the substrate specificity of uridine phosphorylases. It was shown for the first time that the formation of a hydrogen-bond network between the 2′-hydroxy group of uridine and atoms of the active-site residues of uridine phosphorylase leads to conformational changes of the ribose moiety of uridine, resulting in an increase in the reactivity of uridine compared to thymidine. Since the binding of thymidine to residues of uridine phosphorylase causes a smaller local strain of the β-N1-glycosidic bond in this the substrate compared to the uridine molecule, the β-N1-glycosidic bond in thymidine is more stable and less reactive than that in uridine. It was shown for the first time that the phosphate anion, which is the second substrate bound at the active site, interacts simultaneously with the residues of the β5-strand and the β1-strand through hydrogen bonding, thus securing the gate loop in a conformation.« less

  16. Effects of uridine on kindling.

    PubMed

    Zhao, Qian; Shatskikh, Tatiana; Marolewski, Ariane; Rusche, James R; Holmes, Gregory L

    2008-07-01

    The anticonvulsant effect of the nucleoside uridine has been studied for several decades with controversial results. One of its attractive properties is that as a natural endogenous molecule, it lacks the serious side effects of common antiepileptic drugs used today. In the current study, we examined the potential antiepileptogenic effect of uridine in the hippocampal kindling model, using once-daily stimulations. Uridine was administered once or three times daily; levetiracetam was administered as a positive control; and normal saline was used as a negative control. Rats receiving uridine or levetiracetam had slower kindling rates and shorter afterdischarge durations than the normal saline controls. These results are consistent with previous work using a rapid kindling model and suggest that uridine has antiepileptogenic properties. Because of its combination of low toxicity and efficacy, uridine is a possible candidate for the treatment of epilepsy.

  17. Tilted-axis wobbling in odd-mass nuclei

    NASA Astrophysics Data System (ADS)

    Budaca, R.

    2018-02-01

    A triaxial rotor Hamiltonian with a rigidly aligned high-j quasiparticle is treated by a time-dependent variational principle, using angular momentum coherent states. The resulting classical energy function has three unique critical points in a space of generalized conjugate coordinates, which can minimize the energy for specific ordering of the inertial parameters and a fixed angular momentum state. Because of the symmetry of the problem, there are only two unique solutions, corresponding to wobbling motion around a principal axis and, respectively, a tilted axis. The wobbling frequencies are obtained after a quantization procedure and then used to calculate E 2 and M 1 transition probabilities. The analytical results are employed in the study of the wobbling excitations of 135Pr nucleus, which is found to undergo a transition from low angular momentum transverse wobbling around a principal axis toward a tilted-axis wobbling at higher angular momentum.

  18. Phosphorylation of uridine and cytidine by uridine-cytidine kinase.

    PubMed

    Qian, Yahui; Ding, Qingbao; Li, Yanyu; Zou, Zhi; Yan, Bingkun; Ou, Ling

    2014-10-20

    Uridine 5'-monophosphate (5'-UMP) and cytidine 5'-monophosphate (5'-CMP) were biosynthesized by recombinant uridine-cytidine kinase (UCK) and acetate kinase (ACK). The ack and uck genes from Escherichia coli K12 and the uck1, uck2 and ack genes from Lactobacillus bulgaricus ATCC 11842 were cloned and inserted into the plasmid pET-28a. All of the recombinant E. coli strains were capable of overexpressing UCK and ACK, which catalyzed the reaction using guanosine 5'-triphosphate (GTP) as a phosphate intermediate that was regenerated by ACK from acetyl phosphate. The effect of several parameters, including the substrate concentration, the GTP concentration, the temperature and the reaction pH, were optimized. High efficiency was achieved if uridine or cytidine was phosphorylated by UCK encoded by uck from E. coli and ACK encoded by ack from L. bulgaricus. The maximum conversion yield of 5'-UMP and 5'-CMP was 97% at 37 °C and pH 7.5 when 30 mM uridine/cytidine and 0.5mM GTP in a total of 1 mL were used. In addition, the 5'-UMP and 5'-CMP products were very stable in the reaction system and did not undergo significant degradation. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. [The effect of uridine and uridine nucleotides on isolated rat heart performance in regional myocardial ischemia].

    PubMed

    Eliseev, V V; Rodionova, O M; Sapronov, N S; Selizarova, N O

    2002-01-01

    We studied the effects of uridine, uridine-5'-monophosphate (UMP), uridine-5'-diphosphate (UDP) and uridine-5'-triphosphate on contractility, coronary flow and heart rate in isolated perfused rat hearts under 60-minute regional ischemia of the left ventricle. All the compounds (50 mumol/l) induced a positive inotropic effect but had no effect on the heart rate. Uridine and UMP prevented the development of the contracture. UDP and especially UTP increased coronary flow. Probably, a protective effect of uridine and UMP is due to activation of myocardial glycogen synthesis while favourable effects of UDP and UTP on contractility and coronary flow are explained by their influence on P2U-receptors of cardiomyocytes. In addition, coronary dilatation induced by UDP and UTP promoted the reduction of the damaged zone.

  20. Wobbling mode inf {sup 167}Ta.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hartley, D. J.; Janssens, R. V. F.; Riedinger, L. L.

    2009-01-01

    The collective wobbling mode, the strongest signature for the rotation of a triaxial nucleus, has previously been seen only in a few Lu isotopes in spite of extensive searches in nearby isotopes. A sequence of transitions in the N = 94 {sup 167}Ta nucleus exhibiting features similar to those attributed to the wobbling bands in the Lu nuclei has now been found. This band feeds into the {pi}/{sub 13/2} band at a relative energy similar to that seen in the established wobbling bands and its dynamic moment of inertia and alignment properties are nearly identical to the /{sub 13/2} structuremore » over a significant frequency range. Given these characteristics, it is likely that the wobbling mode has been observed for the first time in a nucleus other than Lu, making this collective motion a more general phenomenon.« less

  1. Measuring and correcting wobble in large-scale transmission radiography.

    PubMed

    Rogers, Thomas W; Ollier, James; Morton, Edward J; Griffin, Lewis D

    2017-01-01

    Large-scale transmission radiography scanners are used to image vehicles and cargo containers. Acquired images are inspected for threats by a human operator or a computer algorithm. To make accurate detections, it is important that image values are precise. However, due to the scale (∼5 m tall) of such systems, they can be mechanically unstable, causing the imaging array to wobble during a scan. This leads to an effective loss of precision in the captured image. We consider the measurement of wobble and amelioration of the consequent loss of image precision. Following our previous work, we use Beam Position Detectors (BPDs) to measure the cross-sectional profile of the X-ray beam, allowing for estimation, and thus correction, of wobble. We propose: (i) a model of image formation with a wobbling detector array; (ii) a method of wobble correction derived from this model; (iii) methods for calibrating sensor sensitivities and relative offsets; (iv) a Random Regression Forest based method for instantaneous estimation of detector wobble; and (v) using these estimates to apply corrections to captured images of difficult scenes. We show that these methods are able to correct for 87% of image error due wobble, and when applied to difficult images, a significant visible improvement in the intensity-windowed image quality is observed. The method improves the precision of wobble affected images, which should help improve detection of threats and the identification of different materials in the image.

  2. Comparative study of cardioprotective effects of uridine-5'-monophosphate and uridine-5'-triphosphate during the early periods of acute myocardial ischemia.

    PubMed

    Bul'on, V V; Krylova, I B; Rodionova, O M; Selina, E N; Evdokimova, N R; Sapronov, N S

    2007-09-01

    In experiments on rats, uridine-5'-monophosphate and uridine-5'-triphosphate reduced the intensity of anaerobic glycolysis and preserved glycogen stores and creatine phosphate balance during the first 60 min after occlusion of the left coronary artery. However, the energy-protective effect of uridine-5'-triphosphate developed 15 min later than the effect of uridine-5'-monophosphate. Uridine-5'-monophosphate, but not uridine-5'-triphosphate, reduced T wave amplitude on ECG and decreased the volume of ischemic injury to the myocardium.

  3. Another Look at the Markowitz Wobble

    NASA Astrophysics Data System (ADS)

    Dickman, S. R.

    2006-05-01

    The Markowitz wobble is a small-amplitude, irregular, long-period feature of Earth's polar motion. Despite a contentious history, doubts concerning its existence have apparently faded in recent decades (see, e.g., Poma 2000), and several studies have addressed the question of its excitation. Among the most promising is the proposal by Dumberry & Bloxham (2002; see also Dumberry 2005 and Guo & Buffett 2005) that gravitational and inertial coupling between the mantle and an inner core tilted periodically by outer core hydromagnetic oscillations could - under optimal conditions - reproduce key characteristics of the Markowitz wobble. Those conditions include a moderately high inner core viscosity and high magnetic field strength at the inner core boundary, and fluid core oscillations with a ~ 30-year period. In contrast, oceanic and atmospheric angular momentum variations marginally fail to excite decadal polar motion to the observed level (Gross et al. 2005, also Celaya et al. 1999; but see de Viron et al. 2004). In 1983 I showed that, if the oceans and solid earth were treated as a tightly coupled two-body rotating system, it was possible (depending on the mathematical form of the coupling) for the system to possess 2 natural wobble frequencies corresponding fairly well to the observed Chandler and Markowitz wobbles. The treatment depended on assuming that the oceans respond in an equilibrium manner to rotational perturbations, an approximation justified by the long periods of those wobbles. If the Markowitz wobble is indeed a natural resonance of the ocean - solid earth system, the effectiveness of all proposed excitation sources might require re-evaluation. For this talk I have revisited my earlier investigation, extending the theory to account for dynamic oceanic behavior in response to perturbations of the two-body system's rotation. The extension is based on the "broad-band" approach I employed (in 1993) for determining tidal effects on rotation. Results will

  4. Evaluation of beam wobbling methods for heavy-ion radiotherapy.

    PubMed

    Yonai, Shunsuke; Kanematsu, Nobuyuki; Komori, Masataka; Kanai, Tatsuaki; Takei, Yuka; Takahashi, Osamu; Isobe, Yoshiharu; Tashiro, Mutsumi; Koikegami, Hajime; Tomita, Hideki

    2008-03-01

    The National Institute of Radiological Sciences (NIRS) has extensively studied carbon-ion radiotherapy at the Heavy-Ion Medical Accelerator in Chiba (HIMAC) with some positive outcomes, and has established its efficacy. Therefore, efforts to distribute the therapy to the general public should be made, for which it is essential to enable direct application of clinical and technological experiences obtained at NIRS. For widespread use, it is very important to reduce the cost through facility downsizing with minimal acceleration energy to deliver the HIMAC-equivalent clinical beams. For the beam delivery system, the requirement of miniaturization is translated to reduction in length while maintaining the clinically available field size and penetration range for range-modulated uniform broad beams of regular fields that are either circular or square for simplicity. In this paper, we evaluate the various wobbling methods including original improvements, especially for application to the compact facilities through the experimental and computational studies. The single-ring wobbling method used at HIMAC is the best one including a lot of experience at HIMAC but the residual range is a fatal problem in the case of a compact facility. On the other hand, uniform wobbling methods such as the spiral and zigzag wobbling methods are effective and suitable for a compact facility. Furthermore, these methods can be applied for treatment with passive range modulation including respiratory gated irradiation. In theory, the choice between the spiral and zigzag wobbling methods depends on the shape of the required irradiation field. However, we found that it is better to use the zigzag wobbling method with transformation of the wobbling pattern even when a circular uniform irradiation field is required, because it is difficult to maintain the stability of the wobbler magnet due to the rapid change of the wobbler current in the spiral wobbling method. The regulated wobbling method

  5. Identification and codon reading properties of 5-cyanomethyl uridine, a new modified nucleoside found in the anticodon wobble position of mutant haloarchaeal isoleucine tRNAs

    PubMed Central

    Mandal, Debabrata; Köhrer, Caroline; Su, Dan; Babu, I. Ramesh; Chan, Clement T.Y.; Liu, Yuchen; Söll, Dieter; Blum, Paul; Kuwahara, Masayasu; Dedon, Peter C.; RajBhandary, Uttam L.

    2014-01-01

    Most archaea and bacteria use a modified C in the anticodon wobble position of isoleucine tRNA to base pair with A but not with G of the mRNA. This allows the tRNA to read the isoleucine codon AUA without also reading the methionine codon AUG. To understand why a modified C, and not U or modified U, is used to base pair with A, we mutated the C34 in the anticodon of Haloarcula marismortui isoleucine tRNA (tRNA2Ile) to U, expressed the mutant tRNA in Haloferax volcanii, and purified and analyzed the tRNA. Ribosome binding experiments show that although the wild-type tRNA2Ile binds exclusively to the isoleucine codon AUA, the mutant tRNA binds not only to AUA but also to AUU, another isoleucine codon, and to AUG, a methionine codon. The G34 to U mutant in the anticodon of another H. marismortui isoleucine tRNA species showed similar codon binding properties. Binding of the mutant tRNA to AUG could lead to misreading of the AUG codon and insertion of isoleucine in place of methionine. This result would explain why most archaea and bacteria do not normally use U or a modified U in the anticodon wobble position of isoleucine tRNA for reading the codon AUA. Biochemical and mass spectrometric analyses of the mutant tRNAs have led to the discovery of a new modified nucleoside, 5-cyanomethyl U in the anticodon wobble position of the mutant tRNAs. 5-Cyanomethyl U is present in total tRNAs from euryarchaea but not in crenarchaea, eubacteria, or eukaryotes. PMID:24344322

  6. Glycal Formation in Crystals of Uridine Phosphorylase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paul, Debamita; O’Leary, Sen E.; Rajashankar, Kanagalaghatta

    2010-06-22

    Uridine phosphorylase is a key enzyme in the pyrimidine salvage pathway. This enzyme catalyzes the reversible phosphorolysis of uridine to uracil and ribose 1-phosphate (or 2{prime}-deoxyuridine to 2{prime}-deoxyribose 1-phosphate). Here we report the structure of hexameric Escherichia coli uridine phosphorylase treated with 5-fluorouridine and sulfate and dimeric bovine uridine phosphorylase treated with 5-fluoro-2{prime}-deoxyuridine or uridine, plus sulfate. In each case the electron density shows three separate species corresponding to the pyrimidine base, sulfate, and a ribosyl species, which can be modeled as a glycal. In the structures of the glycal complexes, the fluorouracil O2 atom is appropriately positioned to actmore » as the base required for glycal formation via deprotonation at C2{prime}. Crystals of bovine uridine phosphorylase treated with 2{prime}-deoxyuridine and sulfate show intact nucleoside. NMR time course studies demonstrate that uridine phosphorylase can catalyze the hydrolysis of the fluorinated nucleosides in the absence of phosphate or sulfate, without the release of intermediates or enzyme inactivation. These results add a previously unencountered mechanistic motif to the body of information on glycal formation by enzymes catalyzing the cleavage of glycosyl bonds.« less

  7. Uridine homeostatic disorder leads to DNA damage and tumorigenesis.

    PubMed

    Cao, Zhe; Ma, Jun; Chen, Xinchun; Zhou, Boping; Cai, Chuan; Huang, Dan; Zhang, Xuewen; Cao, Deliang

    2016-03-28

    Uridine is a natural nucleoside precursor of uridine monophosphate in organisms and thus is considered to be safe and is used in a wide range of clinical settings. The far-reaching effects of pharmacological uridine have long been neglected. Here, we report that the homeostatic disorder of uridine is carcinogenic. Targeted disruption (-/-) of murine uridine phosphorylase (UPase) disrupted the homeostasis of uridine and increased spontaneous tumorigenesis by more than 3-fold. Multiple tumors (e.g., lymphoma, hepatoma and lung adenoma) occurred simultaneously in some UPase deficient mice, but not in wild-type mice raised under the same conditions. In the tissue from UPase -/- mice, the 2'-deoxyuridine,5'-triphosphate (dUTP) levels and uracil DNA were increased and p53 was activated with an increased phospho-Ser18 p53 level. Exposing cell lines (e.g., MCF-7, RKO, HCT-8 and NCI-H460) to uridine (10 or 30 µM) led to uracil DNA damage and p53 activation, which in turn triggered the DNA damage response. In these cells, phospho-ATM, phospho-CHK2, and phospho-γH2AX were increased by uridine. These data suggest that uridine homeostatic disorder leads to uracil DNA damage and that pharmacological uridine may be carcinogenic. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Transition state analysis of Trypanosoma cruzi uridine phosphorylase-catalyzed arsenolysis of uridine

    PubMed Central

    Silva, Rafael G.; Vetticatt, Mathew J.; Merino, Emilio F.; Cassera, Maria B.; Schramm, Vern L.

    2011-01-01

    Uridine phosphorylase catalyzes the reversible phosphorolysis of uridine and 2′-deoxyuridine to generate uracil and (2-deoxy)ribose 1-phosphate, an important step in the pyrimidine salvage pathway. The coding sequence annotated as a putative nucleoside phosphorylase in the Trypanosoma cruzi genome was overexpressed in Escherichia coli, purified to homogeneity, and shown to be a homodimeric uridine phosphorylase, with similar specificity for uridine and 2′-deoxyuridine, and undetectable activity towards thymidine and purine nucleosides. Competitive kinetic isotope effects (KIEs) were measured and corrected for a forward commitment factor using arsenate as the nucleophile. The intrinsic KIEs are: 1′-14C = 1.103, 1,3-15N2 = 1.034, 3-15N = 1.004, 1-15N = 1.030, 1′-3H = 1.132, 2′-2H = 1.086 and 5′-3H2 = 1.041 for this reaction. Density functional theory was employed to quantitatively interpret the KIEs in terms of transition state structure and geometry. Matching of experimental KIEs to proposed transition state structures suggests an almost synchronous, SN2-like transition state model, in which the ribosyl moiety possesses significant bond order to both nucleophile and leaving group. Natural bond orbital analysis allowed a comparison of the charge distribution pattern between the ground state and the transition state model. PMID:21599004

  9. Celebrating wobble decoding: Half a century and still much is new.

    PubMed

    Agris, Paul F; Eruysal, Emily R; Narendran, Amithi; Väre, Ville Y P; Vangaveti, Sweta; Ranganathan, Srivathsan V

    2017-08-16

    A simple post-transcriptional modification of tRNA, deamination of adenosine to inosine at the first, or wobble, position of the anticodon, inspired Francis Crick's Wobble Hypothesis 50 years ago. Many more naturally-occurring modifications have been elucidated and continue to be discovered. The post-transcriptional modifications of tRNA's anticodon domain are the most diverse and chemically complex of any RNA modifications. Their contribution with regards to chemistry, structure and dynamics reveal individual and combined effects on tRNA function in recognition of cognate and wobble codons. As forecast by the Modified Wobble Hypothesis 25 years ago, some individual modifications at tRNA's wobble position have evolved to restrict codon recognition whereas others expand the tRNA's ability to read as many as four synonymous codons. Here, we review tRNA wobble codon recognition using specific examples of simple and complex modification chemistries that alter tRNA function. Understanding natural modifications has inspired evolutionary insights and possible innovation in protein synthesis.

  10. In-flight wobble identification for Galileo

    NASA Technical Reports Server (NTRS)

    Lai, J. Y.; Wong, E. C.

    1984-01-01

    To achieve in-flight wobble compensation for Galileo, wobble identification is implemented using star scanner data or automatic gain control (AGC) signal as measurement in all-spin mode. The star scanner provides spacecraft attitude in inertial space while the AGC signal provides the spacecraft pointing relative to earth. A linear observation model is defined for each sensor which is being applied to a Kalman Estimator. It can be shown from simulation that better result can be achieved using a combined set of data than any one sensor alone due to correlation reduction among error sources.

  11. The cardioprotective effect of uridine and uridine-5'-monophosphate: the role of the mitochondrial ATP-dependent potassium channel.

    PubMed

    Krylova, Irina B; Kachaeva, Evgeniya V; Rodionova, Olga M; Negoda, Alexander E; Evdokimova, Nataliya R; Balina, Maria I; Sapronov, Nikolay S; Mironova, Galina D

    2006-07-01

    The activity of mitochondrial ATP-dependent potassium channel (mitoKATP) of rat heart and liver mitochondria was shown to decrease during aging. This partially explains the increase of risk of ischemia at a mature age since mitoKATP activation provides cardioprotection. We demonstrated that uridine-5'-diphosphate (UDP) possesses the property to activate mitoKATP. At a concentration of 30 microM, it reactivated mitoKATP in mitochondria, and 5-hydroxydecanoate (5-HD) eliminated this effect. In experimental animals, UDP precursors uridine and uridine-5'-monophosphate (UMP) (both 30 mg/kg, administered intravenously 5 min before coronary occlusion) decreased the myocardium ischemic alteration index (1.9 and 3.5 times, respectively) and the T-wave amplitude within 60 min after occlusion. Both effects were inhibited by Glibenclamide (Glib) and 5-HD. UMP and uridine decreased the number of premature ventricular beats 5.6 and 1.9 times and the duration of ventricular tachycardia 9.4 and 4.1 times, respectively. Glib and 5-HD inhibited the anti-arrhythmic parameters, 5-HD being less effective. Uridine and UMP decreased the duration of fibrillation 10.8 and 3.6 times, respectively, and this effect was not abolished by Glib and 5-HD. Thus, uridine and UMP, which are the precursors of UDP in the cell, possess cardioprotective properties. MitoKATP prevents mainly ischemic injuries and partially rhythm disorders.

  12. Circular dichroism spectra of uridine derivatives: ChiraSac study.

    PubMed

    Miyahara, Tomoo; Nakatsuji, Hiroshi; Wada, Takehiko

    2014-04-24

    The experimental circular dichroism (CD) spectra of uridine and NH2-uridine that were different in the intensity and shape were studied in the light of the ChiraSac method. The theoretical CD spectra at several different conformations using the symmetry-adapted-cluster configuration-interaction (SAC-CI) theory largely depended on the conformational angle, but those of the anti-conformers and the Boltzmann average reproduced the experimentally obtained CD spectra of both uridine and NH2-uridine. The differences in the CD spectra between the two uridine derivatives were analyzed by using the angle θ between the electric transition dipole moment (ETDM) and the magnetic transition dipole moment (MTDM).

  13. Copper(II) complexes with uridine, uridine 5'-monophosphate, spermidine, or spermine in aqueous solution.

    PubMed

    Lomozik, Lechoslaw; Jastrzab, Renata

    2003-01-15

    Molecular complexes of the types (Urd)H(x)(PA) and (UMP)H(x)(PA) are formed in the uridine (Urd) or uridine 5'-monophosphate (UMP) plus spermidine or spermine systems, as shown by the results of equilibrium and spectral studies. Overall stability constants of the adducts and equilibrium constants of their formation have been determined. An increase in the efficiency of the reaction between the bioligands is observed with increasing length of the polyamine. The pH range of adduct formation is found to coincide with that in which the polyamine is protonated while uridine or its monophosphate is deprotonated. The -NH(x)(+) groups from PA and the N(3) atom of the purine base as well as phosphate groups from the nucleotides have been identified as the significant centres of non-covalent interactions. Compared to cytidine, the pH range of Urd adduct formation is shifted significantly higher due to differences in the protonation constants of the endocyclic N(3) donor atoms of particular nucleosides. Overall stability constants of the Cu(II) complexes with uridine and uridine 5'-monophosphate in ternary systems with spermidine or spermine have been determined. It has been found from spectral data that in the Cu(II) ternary complexes with nucleosides and polyamines the reaction of metallation involves mainly N(3) atoms from the pyrimidine bases, as well as the amine groups of PA. This unexpected type of interaction has been evidenced in the coordination mode of the complexes forming in the Cu-UMP systems including spermidine or spermine. Results of spectral and equilibrium studies indicate that the phosphate groups taking part in metallation are at the same time involved in non-covalent interaction with the protonated polyamine.

  14. A passive pendulum wobble damper for a low spin rate Jupiter flyby spacecraft

    NASA Technical Reports Server (NTRS)

    Fowler, R. C.

    1972-01-01

    When the spacecraft has a low spin rate and precise pointing requirements, the wobble angle must be damped in a time period equivalent to a very few wobble cycles. The design, analysis, and test of a passive pendulum wobble damper are described.

  15. High Frequency Chandler Wobble Excitation

    NASA Astrophysics Data System (ADS)

    Seitz, F.; Stuck, J.; Thomas, M.

    2003-04-01

    Variations of Earth rotation on sub-daily to secular timescales are caused by mass redistributions in the Earth system as a consequence of geophysical processes and gravitational influences. Forced oscillations of polar motion are superposed by free oscillations of the Earth, i.e. the Chandler wobble and the free core nutation. In order to study the interactions between externally induced polar motion and the Earth's free oscillations, a non-linear gyroscopic model has been developed. In most of the former investigations on polar motion, the Chandler wobble is introduced as a damped oscillation with predetermined frequency and amplitude. However, as the effect of rotational deformation is a backcoupling mechanism of polar motion on the Earth's rotational dynamics, both period and amplitude of the Chandler wobble are time-dependent when regarding additional excitations from, e.g., atmospheric or oceanic mass redistributions. The gyroscopic model is free of any explicit information concerning amplitude, phase, and period of free oscillations. The characteristics of the Earth's free oscillation is reproduced by the model from rheological and geometrical parameters and rotational deformation is taken into account. This enables to study the time variable Chandler oscillation when the gyro is forced with atmospheric and oceanic angular momentum from the global atmospheric ECHAM3-T21 general circulation model together with the ocean model for circulation and tides OMCT driven by ECHAM including surface pressure. Besides, mass redistributions in the Earth's body due to gravitational and loading deformations are regarded and external torques exerted by Moon and Sun are considered. The numerical results of the gyro are significantly related with the geodetically observed time series of polar motion published by the IERS. It is shown that the consistent excitation is capable to counteract the damping and thus to maintain the Chandler amplitude. Spectral analyses of the ECHAM

  16. Uridine prevents tamoxifen-induced liver lipid droplet accumulation

    PubMed Central

    2014-01-01

    Background Tamoxifen, an agonist of estrogen receptor, is widely prescribed for the prevention and long-term treatment of breast cancer. A side effect of tamoxifen is fatty liver, which increases the risk for non-alcoholic fatty liver disease. Prevention of tamoxifen-induced fatty liver has the potential to improve the safety of long-term tamoxifen usage. Methods Uridine, a pyrimidine nucleoside with reported protective effects against drug-induced fatty liver, was co-administered with tamoxifen in C57BL/6J mice. Liver lipid levels were evaluated with lipid visualization using coherent anti-Stokes Raman scatting (CARS) microscopy, biochemical assay measurement of triacylglyceride (TAG), and liquid chromatography coupled with mass spectrometry (LC-MS) measurement of membrane phospholipid. Blood TAG and cholesterol levels were measured. Mitochondrial respiration of primary hepatocytes in the presence of tamoxifen and/or uridine was evaluated by measuring oxygen consumption rate with an extracellular flux analyzer. Liver protein lysine acetylation profiles were evaluated with 1D and 2D Western blots. In addition, the relationship between endogenous uridine levels, fatty liver, and tamoxifen administration was evaluated in transgenic mice UPase1−/−and UPase1-TG. Results Uridine co-administration prevented tamoxifen-induced liver lipid droplet accumulation in mice. The most prominent effect of uridine co-administration with tamoxifen was the stimulation of liver membrane phospholipid biosynthesis. Uridine had no protective effect against tamoxifen-induced impairment to mitochondrial respiration of primary hepatocytes or liver TAG and cholesterol export. Uridine had no effect on tamoxifen-induced changes to liver protein acetylation profile. Transgenic mice UPase1−/−with increased pyrimidine salvage activity were protected against tamoxifen-induced liver lipid droplet accumulation. In contrast, UPase1-TG mice with increased pyrimidine catabolism activity had

  17. Uridine prevents tamoxifen-induced liver lipid droplet accumulation.

    PubMed

    Le, Thuc T; Urasaki, Yasuyo; Pizzorno, Giuseppe

    2014-05-23

    Tamoxifen, an agonist of estrogen receptor, is widely prescribed for the prevention and long-term treatment of breast cancer. A side effect of tamoxifen is fatty liver, which increases the risk for non-alcoholic fatty liver disease. Prevention of tamoxifen-induced fatty liver has the potential to improve the safety of long-term tamoxifen usage. Uridine, a pyrimidine nucleoside with reported protective effects against drug-induced fatty liver, was co-administered with tamoxifen in C57BL/6J mice. Liver lipid levels were evaluated with lipid visualization using coherent anti-Stokes Raman scatting (CARS) microscopy, biochemical assay measurement of triacylglyceride (TAG), and liquid chromatography coupled with mass spectrometry (LC-MS) measurement of membrane phospholipid. Blood TAG and cholesterol levels were measured. Mitochondrial respiration of primary hepatocytes in the presence of tamoxifen and/or uridine was evaluated by measuring oxygen consumption rate with an extracellular flux analyzer. Liver protein lysine acetylation profiles were evaluated with 1D and 2D Western blots. In addition, the relationship between endogenous uridine levels, fatty liver, and tamoxifen administration was evaluated in transgenic mice UPase1-/-and UPase1-TG. Uridine co-administration prevented tamoxifen-induced liver lipid droplet accumulation in mice. The most prominent effect of uridine co-administration with tamoxifen was the stimulation of liver membrane phospholipid biosynthesis. Uridine had no protective effect against tamoxifen-induced impairment to mitochondrial respiration of primary hepatocytes or liver TAG and cholesterol export. Uridine had no effect on tamoxifen-induced changes to liver protein acetylation profile. Transgenic mice UPase1-/-with increased pyrimidine salvage activity were protected against tamoxifen-induced liver lipid droplet accumulation. In contrast, UPase1-TG mice with increased pyrimidine catabolism activity had intrinsic liver lipid droplet

  18. Excitation of the Earth's Chandler wobble by a turbulent oceanic double-gyre

    NASA Astrophysics Data System (ADS)

    Naghibi, S. E.; Jalali, M. A.; Karabasov, S. A.; Alam, M.-R.

    2017-04-01

    We develop a layer-averaged, multiple-scale spectral ocean model and show how an oceanic double-gyre can communicate with the Earth's Chandler wobble. The overall transfers of energy and angular momentum from the double-gyre to the Chandler wobble are used to calibrate the turbulence parameters of the layer-averaged model. Our model is tested against a multilayer quasi-geostrophic ocean model in turbulent regime, and base states used in parameter identification are obtained from mesoscale eddy resolving numerical simulations. The Chandler wobble excitation function obtained from the model predicts a small role of North Atlantic ocean region on the wobble dynamics as compared to all oceans, in agreement with the existing observations.

  19. Relationship between plasma uridine and urinary urea excretion.

    PubMed

    Ka, Tuneyoshi; Inokuchi, Taku; Tamada, Daisuke; Suda, Michio; Tsutsumi, Zenta; Okuda, Chihiro; Yamamoto, Asako; Takahashi, Sumio; Moriwaki, Yuji; Yamamoto, Tetsuya

    2010-03-01

    To investigate whether the concentration of uridine in plasma is related to the urinary excretion of urea, 45 healthy male subjects with normouricemia and normal blood pressure were studied after providing informed consent. Immediately after collection of 24-hour urine, blood samples were drawn after an overnight fast except for water. The contents of ingested foods during the 24-hour urine collection period were described by the subjects and analyzed by a dietician. Simple regression analysis showed that plasma uridine was correlated with the urinary excretions of urea (R = 0.41, P < .01), uric acid (R = 0.36, P < .05), and uridine (R = 0.30, P < .05), as well as uric acid clearance (R = 0.35, P < .05) and purine intake (R = 0.30, P < .05). In contrast, multiple regression analysis showed a positive relationship only between plasma uridine and urinary excretion of urea. These results suggest that an increase in de novo pyrimidine synthesis leads to an increased concentration of uridine in plasma via nitrogen catabolism in healthy subjects with normouricemia and normal blood pressure. (c) 2010 Elsevier Inc. All rights reserved.

  20. Analysis of the wobbling effect in a lens-shaped body rotation

    NASA Astrophysics Data System (ADS)

    Kim, Minho

    2017-03-01

    We discuss the wobbling motion in a lens-shaped body rotation, focusing on the frequencies and the amplitude of nutation by filming the rotational motion and wobbling of the body. The friction coefficient of the surface is altered to examine its influence for two lenses with different curvature radii. MATLAB programs are developed to retrieve the Euler angles, which are graphed according to time. It is shown that the lens with a smaller curvature radius exhibits the wobbling effect in all cases, whereas the lens with a larger curvature radius shows such behaviour in limited circumstances. The study confirms that the friction coefficient has a negative linear correlation with the vertical axis declination amplitude with the R-squared value 0.878, showing that friction gives damping and causes smaller axis declination amplitudes. Negative linear correlation also exists with relation to the number of wobbles before the motion stops, where the R-squared value is 0.938, providing further evidence that friction and wobbling cause higher energy dissipation rates. The frequency of the wobbling motion only has a correlation with the curvature radius of the lens, showing no explicit correlation with the friction coefficient, with its R-squared value being 0.077. No losses of contact were observable in this motion. The overall process does not utilize particularly expensive apparatus and will be applicable for senior undergraduate students to experiment on and analyze the motion of a special situation regarding a rigid body that is both spinning and nutating.

  1. Effect of uridine derivatives on myocardial stunning during postischemic reperfusion of rat heart.

    PubMed

    Sapronov, N S; Eliseev, V V; Rodionova, O M

    2000-10-01

    Uridine and uridine-5'-monophosphate prevent myocardial stunning during postischemic reperfusion of isolated rat heart. Uridine-5'-diphosphate does not prevent postischemic myocardial dysfunction, while uridine-5'-triphosphate aggravates it.

  2. Wireless gyroscope platform enabled by a portable media device for quantifying wobble board therapy.

    PubMed

    LeMoyne, Robert; Mastroianni, Timothy

    2017-07-01

    The wobble board enables a therapy strategy for rehabilitation of the ankle foot complex. Quantification of therapy, such as through the use of a wobble board, can facilitate a therapist's acuity for advancing and optimizing the overall therapy strategy. The portable media device, such as an iPod, can be equipped with a software application to function as a wireless gyroscope platform. Integration of the wobble board with the portable media device functioning as a wireless gyroscope enables the potential for patient to therapist interaction through connectivity to the Internet. A patient can conduct wobble board therapy for the ankle foot complex from the convenient vantage point of a homebound setting with therapy data transmitted wirelessly as email attachments. The gyroscope signal of the wobble board therapy can be consolidated into a feature set for machine learning classification. Using a multilayer perceptron neural network considerable classification accuracy has been achieved for differentiating between a hemiplegic affected ankle and unaffected ankle while using a wobble board. The combination of machine learning, wireless systems, such as a portable media device functioning as a wireless gyroscope, and a conventional therapy device, such as a wobble board, are envisioned to advance the capability to optimally impact the rehabilitation experience.

  3. Sulfur Modifications of the Wobble U34 in tRNAs and their Intracellular Localization in Eukaryotic Cells

    PubMed Central

    Nakai, Yumi; Nakai, Masato; Yano, Takato

    2017-01-01

    The wobble uridine (U34) of transfer RNAs (tRNAs) for two-box codon recognition, i.e., tRNALysUUU, tRNAGluUUC, and tRNAGlnUUG, harbor a sulfur- (thio-) and a methyl-derivative structure at the second and fifth positions of U34, respectively. Both modifications are necessary to construct the proper anticodon loop structure and to enable them to exert their functions in translation. Thio-modification of U34 (s2U34) is found in both cytosolic tRNAs (cy-tRNAs) and mitochondrial tRNAs (mt-tRNAs). Although l-cysteine desulfurase is required in both cases, subsequent sulfur transfer pathways to cy-tRNAs and mt-tRNAs are different due to their distinct intracellular locations. The s2U34 formation in cy-tRNAs involves a sulfur delivery system required for the biosynthesis of iron-sulfur (Fe/S) clusters and certain resultant Fe/S proteins. This review addresses presumed sulfur delivery pathways for the s2U34 formation in distinct intracellular locations, especially that for cy-tRNAs in comparison with that for mt-tRNAs. PMID:28218716

  4. Sulfur Modifications of the Wobble U34 in tRNAs and their Intracellular Localization in Eukaryotic Cells.

    PubMed

    Nakai, Yumi; Nakai, Masato; Yano, Takato

    2017-02-18

    The wobble uridine (U 34 ) of transfer RNAs (tRNAs) for two-box codon recognition, i.e., tRNA Lys UUU , tRNA Glu UUC , and tRNA Gln UUG , harbor a sulfur- (thio-) and a methyl-derivative structure at the second and fifth positions of U 34 , respectively. Both modifications are necessary to construct the proper anticodon loop structure and to enable them to exert their functions in translation. Thio-modification of U 34 (s²U 34 ) is found in both cytosolic tRNAs (cy-tRNAs) and mitochondrial tRNAs (mt-tRNAs). Although l-cysteine desulfurase is required in both cases, subsequent sulfur transfer pathways to cy-tRNAs and mt-tRNAs are different due to their distinct intracellular locations. The s²U 34 formation in cy-tRNAs involves a sulfur delivery system required for the biosynthesis of iron-sulfur (Fe/S) clusters and certain resultant Fe/S proteins. This review addresses presumed sulfur delivery pathways for the s²U 34 formation in distinct intracellular locations, especially that for cy-tRNAs in comparison with that for mt-tRNAs.

  5. 5-(Halomethyl)uridine derivatives as potential antitumor radiosensitizers: A DFT study

    NASA Astrophysics Data System (ADS)

    Wang, Shoushan; Zhang, Min; Liu, Peng; Xie, Shilei; Cheng, Faliang; Wang, Lishi

    2018-01-01

    Considering the fact that the efficiency of the uridine-5-methyl radical in producing cytotoxic DNA intrastrand cross-link lesions is greatly higher than that of the uridine-5-yl radical, the radiosensitizing action of 5-(halomethyl)uridines (5-XCH2U, X = F, Cl, or Br) is studied in the present work. It is found that 5-XCH2U has sufficient electron affinity to capture a pre-hydrated or a hydrated electron, and electron attachment leads to significantly facile X- elimination forming the uridine-5-methyl radical. All these three halogenated uridine derivatives are shown to be potential radiosensitizers, with their radiosensitizing abilities increased in an order 5-FCH2U < 5-ClCH2U ≈ 5-BrCH2U.

  6. A cycloidal wobble motor driven by shape memory alloy wires

    NASA Astrophysics Data System (ADS)

    Hwang, Donghyun; Higuchi, Toshiro

    2014-05-01

    A cycloidal wobble motor driven by shape memory alloy (SMA) wires is proposed. In realizing a motor driving mechanism well known as a type of reduction system, a cycloidal gear mechanism is utilized. It facilitates the achievement of bidirectional continuous rotation with high-torque capability, based on its high efficiency and high reduction ratio. The applied driving mechanism consists of a pin/roller based annular gear as a wobbler, a cycloidal disc as a rotor, and crankshafts to guide the eccentric wobbling motion. The wobbling motion of the annular gear is generated by sequential activation of radially phase-symmetrically placed SMA wires. Consequently the cycloidal disc is rotated by rolling contact based cycloidal gearing between the wobbler and the rotor. In designing the proposed motor, thermomechanical characterization of an SMA wire biased by extension springs is experimentally performed. Then, a simplified geometric model for the motor is devised to conduct theoretical assessment of design parametric effects on structural features and working performance. With consideration of the results from parametric analysis, a functional prototype three-phase motor is fabricated to carry out experimental verification of working performance. The observed experimental results including output torque, rotational speed, bidirectional positioning characteristic, etc obviously demonstrate the practical applicability and potentiality of the wobble motor.

  7. Use of uridine triacetate for the management of fluorouracil overdose.

    PubMed

    McEvilly, Margaret; Popelas, Carl; Tremmel, Bob

    2011-10-01

    The use of uridine triacetate for the management of fluorouracil toxicity is reported. A 55-year-old man with malignant neoplasm of the sigmoid colon (stage IIIC) was seen in an outpatient chemotherapy center for his first six-month regimen of leucovorin calcium, fluorouracil, and oxaliplatin. Fluorouracil 2400 mg/m(2) i.v. was prescribed to be given over the next 46 hours at a home infusion center. Due to a medication error, a home infusion pharmacist incorrectly programmed the 46-hour infusion of fluorouracil to be administered over 4 hours. To manage the fluorouracil overdose, the physician decided to start the patient on uridine triacetate. The patient received his first dose of uridine triacetate 18 hours after the fluorouracil overdose. He was admitted to the hospital for observation and daily laboratory tests during treatment with uridine triacetate. He received ondansetron (as the hydrochloride salt) 8 mg orally 20 minutes before each dose of uridine triacetate to prevent nausea and vomiting. Uridine triacetate 11 g every 6 hours was administered orally for a total of 20 doses. It was mixed with applesauce at the time of administration and followed with 8 oz of water. The patient's laboratory values remained stable. The patient did not experience any nausea or vomiting during treatment. He was discharged from the hospital on day 5, with no clinical complications and an Eastern Cooperative Oncology Group Performance score of 0. A patient with colon cancer who had received an overdose of fluorouracil was successfully treated with a five-day course of oral uridine triacetate.

  8. Open-Label Uridine for Treatment of Depressed Adolescents with Bipolar Disorder

    PubMed Central

    Sung, Young-Hoon; Hellem, Tracy L.; Delmastro, Kristen K.; Jeong, Eun-Kee; Kim, Namkug; Shi, Xianfeng; Renshaw, Perry F.

    2011-01-01

    Abstract This report is an open-label case series of seven depressed adolescents with bipolar disorder treated with uridine for 6 weeks. Treatment response was measured with the Children's Depression Rating Scale-Revised and the Clinical Global Impressions scale. Uridine was associated with decreased depressive symptoms, and was well tolerated by study participants. Further systematic studies of uridine are warranted. PMID:21486171

  9. A detection of wobbling brightest cluster galaxies within massive galaxy clusters

    NASA Astrophysics Data System (ADS)

    Harvey, David; Courbin, F.; Kneib, J. P.; McCarthy, Ian G.

    2017-12-01

    A striking signal of dark matter beyond the standard model is the existence of cores in the centre of galaxy clusters. Recent simulations predict that a brightest cluster galaxy (BCG) inside a cored galaxy cluster will exhibit residual wobbling due to previous major mergers, long after the relaxation of the overall cluster. This phenomenon is absent with standard cold dark matter where a cuspy density profile keeps a BCG tightly bound at the centre. We test this hypothesis using cosmological simulations and deep observations of 10 galaxy clusters acting as strong gravitational lenses. Modelling the BCG wobble as a simple harmonic oscillator, we measure the wobble amplitude, Aw, in the BAHAMAS suite of cosmological hydrodynamical simulations, finding an upper limit for the cold dark matter paradigm of Aw < 2 kpc at the 95 per cent confidence limit. We carry out the same test on the data finding a non-zero amplitude of A_w=11.82^{+7.3}_{-3.0} kpc, with the observations dis-favouring Aw = 0 at the 3σ confidence level. This detection of BCG wobbling is evidence for a dark matter core at the heart of galaxy clusters. It also shows that strong lensing models of clusters cannot assume that the BCG is exactly coincident with the large-scale halo. While our small sample of galaxy clusters already indicates a non-zero Aw, with larger surveys, e.g. Euclid, we will be able to not only confirm the effect but also to use it to determine whether or not the wobbling finds its origin in new fundamental physics or astrophysical process.

  10. Excitation of the Earth's Chandler wobble by southern oscillation/El Nino, 1900-1979

    NASA Technical Reports Server (NTRS)

    Chao, B. F.

    1985-01-01

    The southern oscillation/El Nino (ENSO) is the single most prominent interannual signal in global atmospheric/oceanic fluctuations. The following question is addressed: how important is the angular momentum carried by ENSO in exciting the Earth's Chandler wobble? The question is attacked through a statistical analysis of the coherence spectra (correlation as a function of frequency) between two data sets spanning 1900 to 1979-the southern oscillation index (SOI) time series and the excitation function psi (with x-component psi sub x and y-component psi sub y) of the Chandler wobble derived from the homogeneous ILS (International Latitude Service) polar motion data. The coherence power and phase in the Chandler frequency band (approx. 0.79 to 0.89 cpy) are studied. It is found that, during 1900 to 1979 the coherence between SOI and psi sub x is significant well over the 95% confidence threshold whereas that between SOI and psi sub y is practically nil. Quantitatively, the coherence study shows that ENSO provides some 20% of the observed Chandler wobble excitation power. Since earlier investigations have shown that the total atmospheric/oceanic variation can account for the Chandler wobble excitation at about 20% level, the implication is that ENSO maybe an important (interannual) part of the atmospheric/oceanic variation that is responsible for the Chandler wobble excitation during 1900 to 1979.

  11. Gas-phase study on uridine: Conformation and X-ray photofragmentation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Itälä, Eero, E-mail: ersita@utu.fi; Kooser, Kuno; Levola, Helena

    2015-05-21

    Fragmentation of RNA nucleoside uridine, induced by carbon 1s core ionization, has been studied. The measurements by combined electron and ion spectroscopy have been performed in gas phase utilizing synchrotron radiation. As uridine is a combination of d-ribose and uracil, which have been studied earlier with the same method, this study also considers the effect of chemical environment and the relevant functional groups. Furthermore, since in core ionization the initial core hole is always highly localized, charge migration prior to fragmentation has been studied here. This study also demonstrates the destructive nature of core ionization as in most cases themore » C 1s ionization of uridine leads to concerted explosions producing only small fragments with masses ≤43 amu. In addition to fragmentation patterns, we found out that upon evaporation the sugar part of the uridine molecule attains hexagonal form.« less

  12. Characteristics of the uridine uptake system in normal and polyoma transformed hamster embryo cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lemkin, J.A.

    1973-01-01

    The lability of the uridine uptake system in the normal and polyoma transformed hamster embryo fibroblast was studied. The major areas investigated were: the kinetic parameters of uridine transport, a comparison of changes in cellular ATP content by factors which modulate uridine uptake, and a comparison of the qualitative and quantitative effects of the same modulating agent on uridine transport, cell growth, and cellular ATP content. Uridine uptake into cells in vitro was examined using tritiated uridine as a tracer to measure the amount of uridine incorporated into the acid soluble and acid-insoluble fractions of the cells studied. The ATPmore » content of the cells was determined by the firefly bioluminescence method. It was found that the K/sub t/ for uridine uptake into the normal hamster embryo cell and two polyoma transformed hamster embryo cell lines was identical. However, the V/sub max/ for uridine transport was higher in both polyoma transformed cell lines. Furthermore, the K/sub t/ in both the normal and transformed cell cultured in serum-less or serum-containing media was identical, although the V/sub max/ was higher in the serum-stimulated cell in both the normal and transformed cell. Stimulation of the normal cell with adenosine produced a different K/sub t/ for uridine transport. Preliminary investigations have demonstrated that treatment of the polyoma transformed with adenosine also induces a different K/sub t/ (not shown). The K/sub i/ for phloretin inhibition in serum-less and serum-stimulated normal and polyoma transformed cells was found to be identical in each case.« less

  13. Oral uridine-5'-monophosphate (UMP) increases brain CDP-choline levels in gerbils.

    PubMed

    Cansev, Mehmet; Watkins, Carol J; van der Beek, Eline M; Wurtman, Richard J

    2005-10-05

    We examined the biochemical pathways whereby oral uridine-5'-monophosphate (UMP) increases membrane phosphatide synthesis in brains of gerbils. We previously showed that supplementing PC12 cells with uridine caused concentration-related increases in CDP-choline levels, and that this effect was mediated by elevations in intracellular uridine triphosphate (UTP) and cytidine triphosphate (CTP). In the present study, adult gerbils received UMP (1 mmol/kg), a constituent of human breast milk and infant formulas, by gavage, and plasma samples and brains were collected for assay between 5 min and 8 h thereafter. Thirty minutes after gavage, plasma uridine levels were increased from 6.6 +/- 0.58 to 32.7 +/- 1.85 microM (P < 0.001), and brain uridine from 22.6 +/- 2.9 to 89.1 +/- 8.82 pmol/mg tissue (P < 0.001). UMP also significantly increased plasma and brain cytidine levels; however, both basally and following UMP, these levels were much lower than those of uridine. Brain UTP, CTP, and CDP-choline were all elevated 15 min after UMP (from 254 +/- 31.9 to 417 +/- 50.2, [P < 0.05]; 56.8 +/- 1.8 to 71.7 +/- 1.8, [P < 0.001]; and 11.3 +/- 0.5 to 16.4 +/- 1, [P < 0.001] pmol/mg tissue, respectively), returning to basal levels after 20 and 30 min. The smallest UMP dose that significantly increased brain CDP-choline was 0.05 mmol/kg. These results show that oral UMP, a uridine source, enhances the synthesis of CDP-choline, the immediate precursor of PC, in gerbil brain.

  14. Site-specific creation of uridine from cytidine in apolipoprotein B mRNA editing.

    PubMed Central

    Hodges, P E; Navaratnam, N; Greeve, J C; Scott, J

    1991-01-01

    Human apolipoprotein (apo) B mRNA is edited in a tissue specific reaction, to convert glutamine codon 2153 (CAA) to a stop translation codon. The RNA editing product templates and hybridises as uridine, but the chemical nature of this reaction and the physical identity of the product are unknown. After editing in vitro of [32P] labelled RNA, we are able to demonstrate the production of uridine from cytidine; [alpha 32P] cytidine triphosphate incorporated into RNA gave rise to [32P] uridine monophosphate after editing in vitro, hydrolysis with nuclease P1 and thin layer chromatography using two separation systems. By cleaving the RNA into ribonuclease T1 fragments, we show that uridine is produced only at the authentic editing site and is produced in quantities that parallel an independent primer extension assay for editing. We conclude that apo B mRNA editing specifically creates a uridine from a cytidine. These observations are inconsistent with the incorporation of a uridine nucleotide by any polymerase, which would replace the alpha-phosphate and so rule out a model of endonucleolytic excision and repair as the mechanism for the production of uridine. Although transamination and transglycosylation remain to be formally excluded as reaction mechanisms our results argue strongly in favour of the apo B mRNA editing enzyme as a site-specific cytidine deaminase. Images PMID:2030940

  15. Functional and Structural Impact of Target Uridine Substitutions on the H/ACA Ribonucleoprotein Particle Pseudouridine Synthase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhou, Jing; Liang, Bo; Li, Hong

    2010-09-17

    Box H/ACA ribonucleoprotein protein particles catalyze the majority of pseudouridylation in functional RNA. Different from stand alone pseudouridine synthases, the RNP pseudouridine synthase comprises multiple protein subunits and an RNA subunit. Previous studies showed that each subunit, regardless its location, is sensitive to the step of subunit placement at the catalytic center and potentially to the reaction status of the substrate. Here we describe the impact of chemical substitutions of target uridine on enzyme activity and structure. We found that 3-methyluridine in place of uridine inhibited its isomerization while 2{prime}-deoxyuridine or 4-thiouridine did not. Significantly, crystal structures of an archaealmore » box H/ACA RNP bound with the nonreactive and the two postreactive substrate analogues showed only subtle structural changes throughout the assembly except for a conserved tyrosine and a substrate anchoring loop of Cbf5. Our results suggest a potential role of these elements and the subunit that contacts them in substrate binding and product release.« less

  16. Active Site Conformational Dynamics in Human Uridine Phosphorylase 1

    PubMed Central

    Roosild, Tarmo P.; Castronovo, Samantha

    2010-01-01

    Uridine phosphorylase (UPP) is a central enzyme in the pyrimidine salvage pathway, catalyzing the reversible phosphorolysis of uridine to uracil and ribose-1-phosphate. Human UPP activity has been a focus of cancer research due to its role in activating fluoropyrimidine nucleoside chemotherapeutic agents such as 5-fluorouracil (5-FU) and capecitabine. Additionally, specific molecular inhibitors of this enzyme have been found to raise endogenous uridine concentrations, which can produce a cytoprotective effect on normal tissues exposed to these drugs. Here we report the structure of hUPP1 bound to 5-FU at 2.3 Å resolution. Analysis of this structure reveals new insights as to the conformational motions the enzyme undergoes in the course of substrate binding and catalysis. The dimeric enzyme is capable of a large hinge motion between its two domains, facilitating ligand exchange and explaining observed cooperativity between the two active sites in binding phosphate-bearing substrates. Further, a loop toward the back end of the uracil binding pocket is shown to flexibly adjust to the varying chemistry of different compounds through an “induced-fit” association mechanism that was not observed in earlier hUPP1 structures. The details surrounding these dynamic aspects of hUPP1 structure and function provide unexplored avenues to develop novel inhibitors of this protein with improved specificity and increased affinity. Given the recent emergence of new roles for uridine as a neuron protective compound in ischemia and degenerative diseases, such as Alzheimer's and Parkinson's, inhibitors of hUPP1 with greater efficacy, which are able to boost cellular uridine levels without adverse side-effects, may have a wide range of therapeutic applications. PMID:20856879

  17. A geometric model of a V-slit Sun sensor correcting for spacecraft wobble

    NASA Technical Reports Server (NTRS)

    Mcmartin, W. P.; Gambhir, S. S.

    1994-01-01

    A V-Slit sun sensor is body-mounted on a spin-stabilized spacecraft. During injection from a parking or transfer orbit to some final orbit, the spacecraft may not be dynamically balanced. This may result in wobble about the spacecraft spin axis as the spin axis may not be aligned with the spacecraft's axis of symmetry. While the widely used models in Spacecraft Attitude Determination and Control, edited by Wertz, correct for separation, elevation, and azimuthal mounting biases, spacecraft wobble is not taken into consideration. A geometric approach is used to develop a method for measurement of the sun angle which corrects for the magnitude and phase of spacecraft wobble. The algorithm was implemented using a set of standard mathematical routines for spherical geometry on a unit sphere.

  18. Some pharmacological properties of uridine nucleotides

    PubMed Central

    Smith, M. W.

    1964-01-01

    Uridine di-, tri- and monophosphates (UDP, UTP and UMP) contracted the goldfish intestine preparation in that order of decreasing potency. Adenosine triphosphate (ATP) sensitized the gut to UTP and UDP but not to UMP. The fluoro-derivatives of UMP and UTP behaved like the unsubstituted nucleotides on the goldfish intestine but the main effect of 6-azaUDP and large amounts of uracil and uridine was to cause a relaxation. Structure-action relationships are discussed on the basis of these findings. UDPglucose and UDPacetylglucosamine each contracted the goldfish intestine but they were 500-times less active than UDP. Other smooth muscle preparations (tortoise jejunum, rat uterus, guinea-pig ileum and the fowl rectal caecum) contracted to UTP and UDP, but large amounts were needed. The cardiovascular effects in rats of UMP, UDP and UTP were complex and mediated mainly through an action on the peripheral blood vessels. In rats treated with phenoxybenzamine, UMP raised the blood pressure while UDP and UTP first lowered then raised the blood pressure. The fall in blood pressure was not abolished by pronethalol or atropine. The uridine phosphates affected the rat isolated heart only under hypoxic conditions. UTP and UDP dilated the blood vessels of the rabbit ear and UTP was six-times more effective than ATP. UTP and UDP were equiactive in increasing the force of beat of the frog isolated heart. UMP also had an effect if large amounts were given. PMID:14190461

  19. Orotic aciduria and uridine monophosphate synthase: a reappraisal.

    PubMed

    Bailey, C J

    2009-12-01

    Three subtypes of hereditary orotic aciduria are described in the literature, all related to deficiencies in uridine monophosphate synthase, the multifunctional enzyme that contains both orotate: pyrophosphoryl transferase and orotidine monophosphate decarboxylase activities. The type of enzyme defect present in the subtypes has been re-examined by steady-state modelling of the relative outputs of the three enzymic products, uridine monophosphate, urinary orotic acid and urinary orotidine. It is shown that the ratio of urinary outputs of orotidine to orotate provides a means of testing for particular forms of enzyme defect. It is confirmed that the type I defect is caused by loss of uridine monophosphate synthase activity. Cells and tissue of type I cases have a residual amount of activity that is qualitatively unchanged: the relative rates of the transferase and decarboxylase do not differ from those of wild-type enzyme. The single claimed case of type II, thought to be due to specific inactivation of orotidine monophosphate decarboxylase, is shown to have a product spectrum inconsistent with that claim. It is proposed that this type II form does not differ sufficiently to be accepted as separate from type I. The third subtype, hereditary orotic aciduria without megaloblastic anaemia, occurs in two cases. It has the product spectrum expected of a defect in orotidine monophosphate decarboxylase. This form is the only one that appears to have a qualitatively different uridine monophosphate synthase. The possibility that orotidine monophosphate may control flux through the pyrimidine biosynthesis pathway in hereditary orotic aciduria is discussed.

  20. 2' and 3' Carboranyl uridines and their diethyl ether adducts

    DOEpatents

    Soloway, Albert H.; Barth, Rolf F.; Anisuzzaman, Abul K.; Alam, Fazlul; Tjarks, Werner

    1992-01-01

    There is disclosed a process for preparing carboranyl uridine nucleoside compounds and their diethyl ether adducts, which exhibit a tenfold increase in boron content over prior art boron containing nucleoside compounds. Said carboranyl uridine nucleoside compounds exhibit enhanced lipophilicity and hydrophilic properties adequate to enable solvation in aqueous media for subsequent incorporation of said compounds in methods for boron neutron capture therapy in mammalian tumor cells.

  1. Non-covalent and coordination interactions in Cu(II) systems with uridine, uridine 5'-monophosphate and triamine or tetramine as biogenic amine analogues in aqueous solutions.

    PubMed

    Łomozik, Lechosław; Jastrzab, Renata

    2003-10-01

    Reactions of metallation and non-covalent interactions have been studied in ternary systems of Cu(II) ions with uridine, uridine 5'-monophosphate and diamines or triamines. It has been found that in metal-free systems the reaction centres of the nucleoside with the polyamine are the donor nitrogen atoms N(3) and protonated -NH(x) groups of the amines. In comparison to systems with adenosine or cytidine, the pH range of complex formation is shifted towards higher values. It is a consequence of significantly higher basicity of uridine and in agreement with the ion-ion, ion-dipole interaction model assumed. Formation of molecular complexes of uridine 5'-monophosphate with polyamines at a low pH is the result of activity of the phosphate group which plays the role of a negatively charged reaction site. Non-covalent interactions interfere in processes of bioligand metallation. Centres of weak interactions are simultaneously binding sites of metal ions. In protonated Cu(Urd)(PA)H(x) complexes, coordination has been found to involve the N(3) atom from the nucleoside and two donor nitrogen atoms from the polyamine (PA). In the heteroligand species Cu(Urd)(PA), despite deprotonation of all amine groups, one of these groups is located outside the inner coordination sphere. In complexes with uridine-5'-monophosphate, the phosphate group is active in metallation. Moreover, in certain coordination compounds this group is engaged in non-covalent interactions with PA molecules, despite binding Cu ions, as has been shown on the basis of equilibrium and spectral studies.

  2. Wobble pairs of the HDV ribozyme play specific roles in stabilization of active site dynamics.

    PubMed

    Sripathi, Kamali N; Banáš, Pavel; Réblová, Kamila; Šponer, Jiří; Otyepka, Michal; Walter, Nils G

    2015-02-28

    The hepatitis delta virus (HDV) is the only known human pathogen whose genome contains a catalytic RNA motif (ribozyme). The overall architecture of the HDV ribozyme is that of a double-nested pseudoknot, with two GU pairs flanking the active site. Although extensive studies have shown that mutation of either wobble results in decreased catalytic activity, little work has focused on linking these mutations to specific structural effects on catalytic fitness. Here we use molecular dynamics simulations based on an activated structure to probe the active site dynamics as a result of wobble pair mutations. In both wild-type and mutant ribozymes, the in-line fitness of the active site (as a measure of catalytic proficiency) strongly depends on the presence of a C75(N3H3+)N1(O5') hydrogen bond, which positions C75 as the general acid for the reaction. Our mutational analyses show that each GU wobble supports catalytically fit conformations in distinct ways; the reverse G25U20 wobble promotes high in-line fitness, high occupancy of the C75(N3H3+)G1(O5') general-acid hydrogen bond and stabilization of the G1U37 wobble, while the G1U37 wobble acts more locally by stabilizing high in-line fitness and the C75(N3H3+)G1(O5') hydrogen bond. We also find that stable type I A-minor and P1.1 hydrogen bonding above and below the active site, respectively, prevent local structural disorder from spreading and disrupting global conformation. Taken together, our results define specific, often redundant architectural roles for several structural motifs of the HDV ribozyme active site, expanding the known roles of these motifs within all HDV-like ribozymes and other structured RNAs.

  3. Wobble Pairs of the HDV Ribozyme Play Specific Roles in Stabilization of Active Site Dynamics

    PubMed Central

    Sripathi, Kamali N.; Banáš, Pavel; Reblova, Kamila; Šponer, Jiři; Otyepka, Michal

    2015-01-01

    The hepatitis delta virus (HDV) is the only known human pathogen whose genome contains a catalytic RNA motif (ribozyme). The overall architecture of the HDV ribozyme is that of a double-nested pseudoknot, with two GU pairs flanking the active site. Although extensive studies have shown that mutation of either wobble results in decreased catalytic activity, little work has focused on linking these mutations to specific structural effects on catalytic fitness. Here we use molecular dynamics simulations based on an activated structure to probe the active site dynamics as a result of wobble pair mutations. In both wild-type and mutant ribozymes, the in-line fitness of the active site (as a measure of catalytic proficiency) strongly depends on the presence of a C75(N3H3+)N1(O5′) hydrogen bond, which positions C75 as the general acid for the reaction. Our mutational analyses show that each GU wobble supports catalytically fit conformations in distinct ways; the reverse G25U20 wobble promotes high in-line fitness, high occupancy of the C75(N3H3+)G1(O5′) general-acid hydrogen bond and stabilization of the G1U37 wobble, while the G1U37 wobble acts more locally by stabilizing high in-line fitness and the C75(N3H3+)G1(O5′) hydrogen bond. We also find that stable type I A-minor and P1.1 hydrogen bonding above and below the active site, respectively, prevent local structural disorder from spreading and disrupting global conformation. Taken together, our results define specific, often redundant architectural roles for several structural motifs of the HDV ribozyme active site, expanding the known roles of these motifs within all HDV-like ribozymes and other structured RNAs. PMID:25631765

  4. Structure-activity relationships of C6-uridine derivatives targeting plasmodia orotidine monophosphate decarboxylase.

    PubMed

    Bello, Angelica M; Poduch, Ewa; Liu, Yan; Wei, Lianhu; Crandall, Ian; Wang, Xiaoyang; Dyanand, Christopher; Kain, Kevin C; Pai, Emil F; Kotra, Lakshmi P

    2008-02-14

    Malaria, caused by Plasmodia parasites, has re-emerged as a major problem, imposing its fatal effects on human health, especially due to multidrug resistance. In Plasmodia, orotidine 5'-monophosphate decarboxylase (ODCase) is an essential enzyme for the de novo synthesis of uridine 5'-monophosphate. Impairing ODCase in these pathogens is a promising strategy to develop novel classes of therapeutics. Encouraged by our recent discovery that 6-iodo uridine is a potent inhibitor of P. falciparum, we investigated the structure-activity relationships of various C6 derivatives of UMP. 6-Cyano, 6-azido, 6-amino, 6-methyl, 6- N-methylamino, and 6- N, N-dimethylamino derivatives of uridine were evaluated against P. falciparum. The mononucleotides of 6-cyano, 6-azido, 6-amino, and 6-methyl uridine derivatives were studied as inhibitors of plasmodial ODCase. 6-Azidouridine 5'-monophosphate is a potent covalent inhibitor of P. falciparum ODCase. 6-Methyluridine exhibited weak antimalarial activity against P. falciparum 3D7 isolate. 6- N-Methylamino and 6- N, N-dimethylamino uridine derivatives exhibited moderate antimalarial activities.

  5. On the horizontal wobbling of an object levitated by near-field acoustic levitation.

    PubMed

    Kim, Cheol-Ho; Ih, Jeong-Guon

    2007-11-01

    A circular planar object can be levitated with several hundreds of microns by ultrasonic near-field acoustic levitation (NFAL). However, when both the sound source and the levitated object are circularly shaped and the center of the levitated object does not coincide with the source center, instability problem often occurs. When this happens, it becomes difficult to pick up or transport the object for the next process. In this study, when the center of the levitated object was offset from the source center, the moving direction of the levitated object was predicted by using the time averaged potential around the levitated object. The wobbling frequency of the levitated object was calculated by analyzing the nonlinear wobbling motion of the object. It was shown that the predicted wobbling frequencies agreed with measured ones well. Finally, a safe zone was suggested to avoid the unstable movement of an object.

  6. Foot force models of crowd dynamics on a wobbly bridge

    PubMed Central

    Belykh, Igor; Jeter, Russell; Belykh, Vladimir

    2017-01-01

    Modern pedestrian and suspension bridges are designed using industry standard packages, yet disastrous resonant vibrations are observed, necessitating multimillion dollar repairs. Recent examples include pedestrian-induced vibrations during the opening of the Solférino Bridge in Paris in 1999 and the increased bouncing of the Squibb Park Bridge in Brooklyn in 2014. The most prominent example of an unstable lively bridge is the London Millennium Bridge, which started wobbling as a result of pedestrian-bridge interactions. Pedestrian phase locking due to footstep phase adjustment is suspected to be the main cause of its large lateral vibrations; however, its role in the initiation of wobbling was debated. We develop foot force models of pedestrians’ response to bridge motion and detailed, yet analytically tractable, models of crowd phase locking. We use biomechanically inspired models of crowd lateral movement to investigate to what degree pedestrian synchrony must be present for a bridge to wobble significantly and what is a critical crowd size. Our results can be used as a safety guideline for designing pedestrian bridges or limiting the maximum occupancy of an existing bridge. The pedestrian models can be used as “crash test dummies” when numerically probing a specific bridge design. This is particularly important because the U.S. code for designing pedestrian bridges does not contain explicit guidelines that account for the collective pedestrian behavior. PMID:29296679

  7. Foot force models of crowd dynamics on a wobbly bridge.

    PubMed

    Belykh, Igor; Jeter, Russell; Belykh, Vladimir

    2017-11-01

    Modern pedestrian and suspension bridges are designed using industry standard packages, yet disastrous resonant vibrations are observed, necessitating multimillion dollar repairs. Recent examples include pedestrian-induced vibrations during the opening of the Solférino Bridge in Paris in 1999 and the increased bouncing of the Squibb Park Bridge in Brooklyn in 2014. The most prominent example of an unstable lively bridge is the London Millennium Bridge, which started wobbling as a result of pedestrian-bridge interactions. Pedestrian phase locking due to footstep phase adjustment is suspected to be the main cause of its large lateral vibrations; however, its role in the initiation of wobbling was debated. We develop foot force models of pedestrians' response to bridge motion and detailed, yet analytically tractable, models of crowd phase locking. We use biomechanically inspired models of crowd lateral movement to investigate to what degree pedestrian synchrony must be present for a bridge to wobble significantly and what is a critical crowd size. Our results can be used as a safety guideline for designing pedestrian bridges or limiting the maximum occupancy of an existing bridge. The pedestrian models can be used as "crash test dummies" when numerically probing a specific bridge design. This is particularly important because the U.S. code for designing pedestrian bridges does not contain explicit guidelines that account for the collective pedestrian behavior.

  8. Elongator Complex Influences Telomeric Gene Silencing and DNA Damage Response by Its Role in Wobble Uridine tRNA Modification

    PubMed Central

    Chen, Changchun; Huang, Bo; Eliasson, Mattias; Rydén, Patrik; Byström, Anders S.

    2011-01-01

    Elongator complex is required for formation of the side chains at position 5 of modified nucleosides 5-carbamoylmethyluridine (ncm5U34), 5-methoxycarbonylmethyluridine (mcm5U34), and 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U34) at wobble position in tRNA. These modified nucleosides are important for efficient decoding during translation. In a recent publication, Elongator complex was implicated to participate in telomeric gene silencing and DNA damage response by interacting with proliferating cell nuclear antigen (PCNA). Here we show that elevated levels of tRNALys s2 UUU, tRNAGln s2 UUG, and tRNAGlu s2 UUC, which in a wild-type background contain the mcm5s2U nucleoside at position 34, suppress the defects in telomeric gene silencing and DNA damage response observed in the Elongator mutants. We also found that the reported differences in telomeric gene silencing and DNA damage response of various elp3 alleles correlated with the levels of modified nucleosides at U34. Defects in telomeric gene silencing and DNA damage response are also observed in strains with the tuc2Δ mutation, which abolish the formation of the 2-thio group of the mcm5s2U nucleoside in tRNALys mcm5s2UUU, tRNAGln mcm5s2UUG, and tRNAGlu mcm5s2UUC. These observations show that Elongator complex does not directly participate in telomeric gene silencing and DNA damage response, but rather that modified nucleosides at U34 are important for efficient expression of gene products involved in these processes. Consistent with this notion, we found that expression of Sir4, a silent information regulator required for assembly of silent chromatin at telomeres, was decreased in the elp3Δ mutants. PMID:21912530

  9. Elongator complex influences telomeric gene silencing and DNA damage response by its role in wobble uridine tRNA modification.

    PubMed

    Chen, Changchun; Huang, Bo; Eliasson, Mattias; Rydén, Patrik; Byström, Anders S

    2011-09-01

    Elongator complex is required for formation of the side chains at position 5 of modified nucleosides 5-carbamoylmethyluridine (ncm⁵U₃₄), 5-methoxycarbonylmethyluridine (mcm⁵U₃₄), and 5-methoxycarbonylmethyl-2-thiouridine (mcm⁵s²U₃₄) at wobble position in tRNA. These modified nucleosides are important for efficient decoding during translation. In a recent publication, Elongator complex was implicated to participate in telomeric gene silencing and DNA damage response by interacting with proliferating cell nuclear antigen (PCNA). Here we show that elevated levels of tRNA(Lys)(s²UUU), tRNA(Gln)(s²UUG), and tRNA(Glu)(s²UUC), which in a wild-type background contain the mcm⁵s²U nucleoside at position 34, suppress the defects in telomeric gene silencing and DNA damage response observed in the Elongator mutants. We also found that the reported differences in telomeric gene silencing and DNA damage response of various elp3 alleles correlated with the levels of modified nucleosides at U₃₄. Defects in telomeric gene silencing and DNA damage response are also observed in strains with the tuc2Δ mutation, which abolish the formation of the 2-thio group of the mcm⁵s²U nucleoside in tRNA(Lys)(mcm⁵s²UUU), tRNA(Gln)(mcm⁵s²UUG), and tRNA(Glu)(mcm⁵s²UUC). These observations show that Elongator complex does not directly participate in telomeric gene silencing and DNA damage response, but rather that modified nucleosides at U₃₄ are important for efficient expression of gene products involved in these processes. Consistent with this notion, we found that expression of Sir4, a silent information regulator required for assembly of silent chromatin at telomeres, was decreased in the elp3Δ mutants.

  10. Synthesis and interaction of sterol-uridine conjugate with DMPC liposomes studied by differential scanning calorimetry.

    PubMed

    Escobar, Jhon Fernando Berrío; Restrepo, Manuel Humberto Pastrana; Fernández, Diana Margarita Márquez; Martínez, Alejandro Martínez; Giordani, Cristiano; Castelli, Francesco; Sarpietro, Maria Grazia

    2018-06-01

    Differential scanning calorimetry (DSC) is a thermoanalytical technique which provides information on the interaction between drugs and models of cell membranes. Studies on the calorimetric behavior of hydrated phospholipids within liposomes are employed to shed light on the changes in the physico-chemical properties when interacting with drugs. In this report, new potential anti-cancer drugs such as uridine and uridine derivatives (acetonide and its succinate), 3β-5α,8α-endoperoxide-cholestan-6-en-3-ol (5,8-epidioxicholesterol) and conjugate (uridine acetonide-epidioxicholesterol succinate) have been synthesized. Steglich esterification method using coupling agents allowed to obtain the uridine acetonide-sterol conjugate. The study on the interaction between the drugs and dimiristoyl-phophatidilcholine (DMPC) liposomes has been conducted by the use of DSC. The analysis of the DSC curves indicated that the uridine and derivatives (acetonide and its succinate) present a very soft interaction with the DMPC liposomes, whereas the 5,8-epidioxicholesterol and the conjugate showed a strong effect on the thermotropic behavior. Our results suggested that the lipophilic character of uridine acetonide-sterol conjugate improves the affinity with the DMPC liposomes. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. CAD mutations and uridine-responsive epileptic encephalopathy.

    PubMed

    Koch, Johannes; Mayr, Johannes A; Alhaddad, Bader; Rauscher, Christian; Bierau, Jörgen; Kovacs-Nagy, Reka; Coene, Karlien L M; Bader, Ingrid; Holzhacker, Monika; Prokisch, Holger; Venselaar, Hanka; Wevers, Ron A; Distelmaier, Felix; Polster, Tilman; Leiz, Steffen; Betzler, Cornelia; Strom, Tim M; Sperl, Wolfgang; Meitinger, Thomas; Wortmann, Saskia B; Haack, Tobias B

    2017-02-01

    Unexplained global developmental delay and epilepsy in childhood pose a major socioeconomic burden. Progress in defining the molecular bases does not often translate into effective treatment. Notable exceptions include certain inborn errors of metabolism amenable to dietary intervention. CAD encodes a multifunctional enzyme involved in de novo pyrimidine biosynthesis. Alternatively, pyrimidines can be recycled from uridine. Exome sequencing in three families identified biallelic CAD mutations in four children with global developmental delay, epileptic encephalopathy, and anaemia with anisopoikilocytosis. Two died aged 4 and 5 years after a neurodegenerative disease course. Supplementation of the two surviving children with oral uridine led to immediate cessation of seizures in both. A 4-year-old female, previously in a minimally conscious state, began to communicate and walk with assistance after 9 weeks of treatment. A 3-year-old female likewise showed developmental progress. Blood smears normalized and anaemia resolved. We establish CAD as a gene confidently implicated in this neurometabolic disorder, characterized by co-occurrence of global developmental delay, dyserythropoietic anaemia and seizures. While the natural disease course can be lethal in early childhood, our findings support the efficacy of uridine supplementation, rendering CAD deficiency a treatable neurometabolic disorder and therefore a potential condition for future (genetic) newborn screening. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. A single amino acid limits the substrate specificity of Thermus thermophilus uridine-cytidine kinase to cytidine.

    PubMed

    Tomoike, Fumiaki; Nakagawa, Noriko; Kuramitsu, Seiki; Masui, Ryoji

    2011-05-31

    The salvage pathways of nucleotide biosynthesis are more diverse and are less well understood as compared with de novo pathways. Uridine-cytidine kinase (UCK) is the rate-limiting enzyme in the pyrimidine-nucleotide salvage pathway. In this study, we have characterized a UCK homologue of Thermus thermophilus HB8 (ttCK) biochemically and structurally. Unlike other UCKs, ttCK had substrate specificity toward only cytidine and showed no inhibition by UTP, suggesting uridine does not bind to ttCK as substrate. Structural analysis revealed that the histidine residue located near the functional group at position 4 of cytidine or uridine in most UCKs is substituted with tyrosine, Tyr93, in ttCK. Replacement of Tyr93 by histidine or glutamine endowed ttCK with phosphorylation activity toward uridine. These results suggested that a single amino acid residue, Tyr93, gives cytidine-limited specificity to ttCK. However, replacement of Tyr93 by Phe or Leu did not change the substrate specificity of ttCK. Therefore, we conclude that a residue at this position is essential for the recognition of uridine by UCK. In addition, thymidine phosphorylase from T. thermophilus HB8 was equally active with thymidine and uridine, which indicates that this protein is the sole enzyme metabolizing uridine in T. Thermophilus HB8. On the basis of these results, we discuss the pyrimidine-salvage pathway in T. thermophilus HB8.

  13. Reduction of wobble-position GC bases in Corynebacteria genes and enhancement of PCR and heterologous expression.

    PubMed

    Sanli, G; Blaber, S I; Blaber, M

    2001-01-01

    Corynebacteria codon usage exhibits an overall GC content of 67%, and a wobble-position GC content of 88%. Escherichia coli, on the other hand has an overall GC content of 51%, and a wobble-position GC content of 55%. The high GC content of Corynebacteria genes results in an unfavorable codon preference for heterologous expression, and can present difficulties for polymerase-based manipulations due to secondary-structure effects. Since these characteristics are due primarily to base composition at the wobble-position, synthetic genes can, in principle, be designed to eliminate these problems and retain the wild-type amino acid sequence. Such genes would obviate the need for special additives or bases during in vitro polymerase-based manipulation and mutant host strains containing uncommon tRNA's for heterologous expression. We have evaluated synthetic genes with reduced wobble-position G/C content using two variants of the enzyme 2,5-diketo-D-gluconic acid reductase (2,5-DKGR A and B) from Corynebacterium. The wild-type genes are refractory to polymerase-based manipulations and exhibit poor heterologous expression in enteric bacteria. The results indicate that a subset of codons for five amino acids (alanine, arginine, glutamate, glycine and valine) contribute the greatest contribution to reduction in G/C content at the wobble-position. Furthermore, changes in codons for two amino acids (leucine and proline) enhance bias for expression in enteric bacteria without affecting the overall G/C content. The synthetic genes are readily amplified using polymerase-based methodologies, and exhibit high levels of heterologous expression in E. coli.

  14. 2[prime] and 3[prime] Carboranyl uridines and their diethyl ether adducts

    DOEpatents

    Soloway, A.H.; Barth, R.F.; Anisuzzaman, A.K.; Alam, F.; Tjarks, W.

    1992-12-15

    A process is described for preparing carboranyl uridine nucleoside compounds and their diethyl ether adducts, which exhibit a tenfold increase in boron content over prior art boron containing nucleoside compounds. The carboranyl uridine nucleoside compounds exhibit enhanced lipophilicity and hydrophilic properties adequate to enable solvation in aqueous media for subsequent incorporation of the compounds in methods for boron neutron capture therapy in mammalian tumor cells. No Drawings

  15. Uridine-Ribohydrolase Is a Key Regulator in the Uridine Degradation Pathway of Arabidopsis[W

    PubMed Central

    Jung, Benjamin; Flörchinger, Martin; Kunz, Hans-Henning; Traub, Michaela; Wartenberg, Ruth; Jeblick, Wolfgang; Neuhaus, H. Ekkehard; Möhlmann, Torsten

    2009-01-01

    Nucleoside degradation and salvage are important metabolic pathways but hardly understood in plants. Recent work on human pathogenic protozoans like Leishmania and Trypanosoma substantiates an essential function of nucleosidase activity. Plant nucleosidases are related to those from protozoans and connect the pathways of nucleoside degradation and salvage. Here, we describe the cloning of such an enzyme from Arabidopsis thaliana, Uridine-Ribohydrolase 1 (URH1) and the characterization by complementation of a yeast mutant. Furthermore, URH1 was synthesized as a recombinant protein in Escherichia coli. The pure recombinant protein exhibited highest hydrolase activity for uridine, followed by inosine and adenosine, the corresponding Km values were 0.8, 1.4, and 0.7 mM, respectively. In addition, URH1 was able to cleave the cytokinin derivative isopentenyladenine-riboside. Promoter β-glucuronidase fusion studies revealed that URH1 is mainly transcribed in the vascular cells of roots and in root tips, guard cells, and pollen. Mutants expressing the Arabidopsis enzyme or the homolog from rice (Oryza sativa) exhibit resistance toward toxic fluorouridine, fluorouracil, and fluoroorotic acid, providing clear evidence for a pivotal function of URH1 as regulative in pyrimidine degradation. Moreover, mutants with increased and decreased nucleosidase activity are delayed in germination, indicating that this enzyme activity must be well balanced in the early phase of plant development. PMID:19293370

  16. Truncation effects in computing free wobble/nutation modes explored using a simple Earth model

    NASA Astrophysics Data System (ADS)

    Seyed-Mahmoud, Behnam; Rochester, Michael G.; Rogers, Christopher M.

    2017-06-01

    The displacement field accompanying the wobble/nutation of the Earth is conventionally represented by an infinite chain of toroidal and spheroidal vector spherical harmonics, coupled by rotation and ellipticity. Numerical solutions for the eigenperiods require truncation of that chain, and the standard approaches using the linear momentum description (LMD) of deformation during wobble/nutation have truncated it at very low degrees, usually degree 3 or 4, and at most degree 5. The effects of such heavy truncation on the computed eigenperiods have hardly been examined. We here investigate the truncation effects on the periods of the free wobble/nutation modes using a simplified Earth model consisting of a homogeneous incompressible inviscid liquid outer core with a rigid (but not fixed) inner core and mantle. A novel Galerkin method is implemented using a Clairaut coordinate system to solve the classic Poincaré problem in the liquid core and, to close the problem, we use the Lagrangean formulation of the Liouville equation for each of the solid parts of the Earth model. We find that, except for the free inner core nutation (FICN), the periods of the free rotational modes converge rather quickly. The period of the tiltover mode is found to excellent accuracy. The computed periods of the Chandler wobble and free core nutation are nearly identical to the values cited in the literature for similar Earth models, but that for the inner core wobble is slightly different. Truncation at low-degree harmonics causes the FICN period to fluctuate over a range as large as 90 sd, with different values at different truncation levels. For example, truncation at degree 6 gives a period of 752 sd (almost identical with the value cited in the literature for such an Earth model) but truncation at degree 24 is required to obtain convergence, and the resulting period is 746 ± 1 sd, as more terms are included, with no guarantee that its proximity to earlier values is other than fortuitous

  17. Truncation Effects in Computing Free Wobble/Nutation Modes Explored Using a Simple Earth Model

    NASA Astrophysics Data System (ADS)

    Seyed-Mahmoud, B.; Rochester, M. G.; Rogers, C. M.

    2016-12-01

    The displacement field accompanying the wobble/nutation of the Earth is conventionally represented by an infinite chain of toroidal and spheroidal vector spherical harmonics, coupled by rotation and ellipticity. Numerical solutions for the eigenperiods require truncation of that chain, and the standard approaches using the linear momentum description (LMD) of deformation during wobble/nutation have truncated it at very low degrees, usually degree 3 or 4, and at most degree 5. The effects of such heavy truncation on the computed eigenperiods have hardly been examined. We here investigate the truncation effects on the periods of the free wobble/nutation modes using a simplified Earth model consisting of a homogeneous incompressible inviscid liquid outer core with a rigid (but not fixed) inner core and mantle. A novel Galerkin method is implemented using a Clairaut coordinate system to solve the classic Poincare problem in the liquid core and, to close the problem, we use the Lagrangean formulation of the Liouville equation for each of the solid parts of the Earth model. We find that, except for the free inner core nutation (FICN), the periods of the free rotational modes converge rather quickly. The period of the tiltover mode (TOM) is found to excellent accuracy. The computed periods of the Chandler wobble (CW) and free core nutation (FCN) are nearly identical to the values cited in the literature for similar Earth models, but that for the inner core wobble (ICW) is slightly different. Truncation at low-degree harmonics causes the FICN period to fluctuate over a range as large as 90 sd, with different values at different truncation levels. For example, truncation at degree 6 gives a period of 752 sd (almost identical with the value cited in the literature for such an Earth model) but truncation at degree 24 is required to obtain convergence, and the resulting period is 746 sd, with no guarantee that its proximity to earlier values is other than fortuitous. We

  18. Uridine Metabolism in HIV-1-Infected Patients: Effect of Infection, of Antiretroviral Therapy and of HIV-1/ART-Associated Lipodystrophy Syndrome

    PubMed Central

    Domingo, Pere; Torres-Torronteras, Javier; Pomar, Virginia; Giralt, Marta; Domingo, Joan Carles; Gutierrez, Maria del Mar; Gallego-Escuredo, José M.; Mateo, Maria Gracia; Cano-Soldado, Pedro; Fernandez, Irene; Pastor-Anglada, Marçal; Vidal, Francesc; Villarroya, Francesc; Andreu, Antoni; Marti, Ramon

    2010-01-01

    Background Uridine has been advocated for the treatment of HIV-1/HAART-associated lipodystrophy (HALS), although its metabolism in HIV-1-infected patients is poorly understood. Methods Plasma uridine concentrations were measured in 35 controls and 221 HIV-1-infected patients and fat uridine in 15 controls and 19 patients. The diagnosis of HALS was performed following the criteria of the Lipodystrophy Severity Grading Scale. Uridine was measured by a binary gradient-elution HPLC method. Analysis of genes encoding uridine metabolizing enzymes in fat was performed with TaqMan RT-PCR. Results Median plasma uridine concentrations for HIV-1-infected patients were 3.80 µmol/l (interquartile range: 1.60), and for controls 4.60 µmol/l (IQR: 1.8) (P = 0.0009). In fat, they were of 6.0 (3.67), and 2.8 (4.65) nmol/mg of protein, respectively (P = 0.0118). Patients with a mixed HALS form had a median plasma uridine level of 4.0 (IC95%: 3.40–4.80) whereas in those with isolated lipoatrophy it was 3.25 (2.55–4.15) µmol/l/l (P = 0.0066). The expression of uridine cytidine kinase and uridine phosphorylase genes was significantly decreased in all groups of patients with respect to controls. A higher expression of the mRNAs for concentrative nucleoside transporters was found in HIV-1-infected patients with respect to healthy controls. Conclusions HIV-1 infection is associated with a decrease in plasma uridine and a shift of uridine to the adipose tissue compartment. Antiretroviral therapy was not associated with plasma uridine concentrations, but pure lipoatrophic HALS was associated with significantly lower plasma uridine concentrations. PMID:21085568

  19. Two-Dimensional Collective Hamiltonian for Chiral and Wobbling Modes

    DOE PAGES

    Chen, Q. B.; Zhang, S. Q.; Zhao, P. W.; ...

    2016-10-03

    Here, a two-dimensional collective Hamiltonian (2DCH) on both azimuth and polar motions in triaxial nuclei is proposed to investigate the chiral and wobbling modes. In the 2DCH, the collective potential and the mass parameters are determined from three-dimensional tilted axis cranking (TAC) calculations. The broken chiral and signature symmetries in the TAC solutions are restored by the 2DCH. The validity of the 2DCH is illustrated with a triaxial rotor (γ= -30°) coupling to one h 11/2 proton particle and one h 11/2 neutron hole. By diagonalizing the 2DCH, the angular momenta and energy spectra are obtained. These results agree withmore » the exact solutions of the particle rotor model (PRM) at high rotational frequencies. However, at low frequencies, the energies given by the 2DCH are larger than those by the PRM due to the underestimation of the mass parameters. In addition, with increasing angular momentum, the transitions from the chiral vibration to chiral rotation and further to longitudinal wobbling motion have been presented in the 2DCH.« less

  20. Two-Dimensional Collective Hamiltonian for Chiral and Wobbling Modes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Q. B.; Zhang, S. Q.; Zhao, P. W.

    Here, a two-dimensional collective Hamiltonian (2DCH) on both azimuth and polar motions in triaxial nuclei is proposed to investigate the chiral and wobbling modes. In the 2DCH, the collective potential and the mass parameters are determined from three-dimensional tilted axis cranking (TAC) calculations. The broken chiral and signature symmetries in the TAC solutions are restored by the 2DCH. The validity of the 2DCH is illustrated with a triaxial rotor (γ= -30°) coupling to one h 11/2 proton particle and one h 11/2 neutron hole. By diagonalizing the 2DCH, the angular momenta and energy spectra are obtained. These results agree withmore » the exact solutions of the particle rotor model (PRM) at high rotational frequencies. However, at low frequencies, the energies given by the 2DCH are larger than those by the PRM due to the underestimation of the mass parameters. In addition, with increasing angular momentum, the transitions from the chiral vibration to chiral rotation and further to longitudinal wobbling motion have been presented in the 2DCH.« less

  1. WOBBLE: A Proposed Mission to Characterize Past and Present Water on Mars

    NASA Technical Reports Server (NTRS)

    Udrea, Bogdan; Delory, Greg; Landis, Geoffrey; Duvet, Ludovic; Choudhuri, Ahsan; Prina, Mauro; Moreels, Pierre; Bedard, Donald; Furano, Gianluca

    2002-01-01

    WOBBLE ("Water Observations from a Balloon Borne Light Explorer") is a mission concept study for a small robotic probe to explore Mars and to accomplish a scientific mission compatible with the goals of the NASA Code S enterprise. The detection of past or present water is a crucial goal for Mars exploration, representing a cross-cutting science theme relevant to past or extant life, climate history, sample return missions and eventual human exploration. The WOBBLE mission concept was developed to study evidence of water using in-situ detection methods. The features on Mars most suited to this investigation are the gullies identified by Malin and Edgett as evidence for recent, near-surface runoff of liquid water. These features are typically located on the inside face of crater rims, where the local slope angle is at or near the angle of repose. This makes the terrain difficult or impossible to access with conventional wheeled rover technology. Combined with the small size of the gullies in relation to a standard landing error ellipse, scientific investigation of these features requires a new approach to surface mobility. WOBBLE uses a low-altitude balloon-borne platform to traverse the surface from the landing site, to the investigation site, and then rise up the slope to investigate the regions of interest at close range. Of the mobility technologies available for near-term Mars exploration, only a balloon platform is capable of a well targeted, detailed sampling of the gully regions over periods of days or more. The science approach embodied in WOBBLE is two-pronged, designed to investigate both the historical evidence of liquid water utilizing high-resolution geomorphology and the characterization of mineral deposits, and present subsurface liquid water using radar sounding techniques. The WOBBLE balloon is a high-pressure hydrogen gas design, 24 meters in diameter and lifting a total payload of 130 kg, including a high-resolution camera/IR imager, Raman

  2. Isolation, crystallization and preliminary crystallographic analysis of Salmonella typhimurium uridine phosphorylase crystallized with 2,2′-anhydrouridine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Timofeev, Vladimir I.; Lashkov, Alexander A.; Gabdoulkhakov, Azat G.

    2007-10-01

    S. typhimurium uridine phosphorylase has been isolated and crystallized in the presence of ligand. Uridine phosphorylase (UPh; EC 2.4.2.3) is a member of the pyrimidine nucleoside phosphorylase family of enzymes which catalyzes the phosphorolytic cleavage of the C—N glycoside bond of uridine, with the formation of ribose 1-phosphate and uracil. This enzyme has been shown to be important in the activation and catabolism of fluoropyrimidines. Modulation of its enzymatic activity may affect the therapeutic efficacy of chemotherapeutic agents. The structural investigation of the bacterial uridine phosphorylases, both unliganded and complexed with substrate/product analogues and inhibitors, may help in understanding themore » catalytic mechanism of the phosphorolytic cleavage of uridine. Salmonella typhimurium uridine phosphorylase has been crystallized with 2,2′-anhydrouridine. X-ray diffraction data were collected to 2.15 Å. Preliminary analysis of the diffraction data indicates that the crystal belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 88.52, b = 123.98, c = 133.52 Å. The solvent content is 45.51%, assuming the presence of one hexamer molecule per asymmetric unit.« less

  3. A Xanthomonas uridine 5'-monophosphate transferase inhibits plant immune kinases.

    PubMed

    Feng, Feng; Yang, Fan; Rong, Wei; Wu, Xiaogang; Zhang, Jie; Chen, She; He, Chaozu; Zhou, Jian-Min

    2012-04-15

    Plant innate immunity is activated on the detection of pathogen-associated molecular patterns (PAMPs) at the cell surface, or of pathogen effector proteins inside the plant cell. Together, PAMP-triggered immunity and effector-triggered immunity constitute powerful defences against various phytopathogens. Pathogenic bacteria inject a variety of effector proteins into the host cell to assist infection or propagation. A number of effector proteins have been shown to inhibit plant immunity, but the biochemical basis remains unknown for the vast majority of these effectors. Here we show that the Xanthomonas campestris pathovar campestris type III effector AvrAC enhances virulence and inhibits plant immunity by specifically targeting Arabidopsis BIK1 and RIPK, two receptor-like cytoplasmic kinases known to mediate immune signalling. AvrAC is a uridylyl transferase that adds uridine 5'-monophosphate to and conceals conserved phosphorylation sites in the activation loop of BIK1 and RIPK, reducing their kinase activity and consequently inhibiting downstream signalling.

  4. Preliminary effects of oral uridine on the ocular surface in dry eye patients.

    PubMed

    Chang, Ki Cheol; Oh, Joo Youn; In, Youn Seok; Kim, Mee Kum; Shin, Ki Cheul; Wee, Won Ryang; Lee, Jin Hak; Park, Myung Gyu

    2009-08-01

    We designed a randomized, double blinded, 3-months controlled prospective clinical study to investigate effects of oral uridine on the ocular surface in dry eye patients. Twenty-seven patients who diagnosed as dry eye with lower than 5 mm of wetting in the Schirmer strip, with corneal epithelial erosion and who completely followed-up till 3 months were enrolled. Corneal-conjunctival fluorescein staining, non-anesthetic Schirmer test, impression cytology, and Ocular Surface Disease Index (OSDI) were evaluated in the experimental and placebo groups at the baseline, 1 and 3 months after start of medication in a double blinded manner. Fluorescein stain score of the cornea was markedly decreased in oral uridine group compared to the placebo group at 3 months after medication (P=0.032, Mann-Whitney U test). The Schirmer wetting score for the oral uridine group was significantly increased (P=0.001, Wilcoxon signed rank test) at 3 months and its difference between two groups was statistically significant (P=0.030, Mann-Whitney U test). OSDI scores were significantly decreased at 1 and 3 months in treatment group. Oral uridine is effective in treatment of dry eyes.

  5. Probing the Watson-Crick, wobble, and sugar-edge hydrogen bond sites of uracil and thymine.

    PubMed

    Müller, Andreas; Frey, Jann A; Leutwyler, Samuel

    2005-06-16

    The nucleobases uracil (U) and thymine (T) offer three hydrogen-bonding sites for double H-bond formation via neighboring N-H and C=O groups, giving rise to the Watson-Crick, wobble and sugar-edge hydrogen bond isomers. We probe the hydrogen bond properties of all three sites by forming hydrogen bonded dimers of U, 1-methyluracil (1MU), 3-methyluracil (3MU), and T with 2-pyridone (2PY). The mass- and isomer-specific S1 <-- S0 vibronic spectra of 2PY.U, 2PY.3MU, 2PY.1MU, and 2PY.T were measured using UV laser resonant two-photon ionization (R2PI). The spectra of the Watson-Crick and wobble isomers of 2PY.1MU were separated using UV-UV spectral hole-burning. We identify the different isomers by combining three different diagnostic tools: (1) Selective methylation of the uracil N3-H group, which allows formation of the sugar-edge isomer only, and methylation of the N1-H group, which leads to formation of the Watson-Crick and wobble isomers. (2) The experimental S1 <-- S0 origins exhibit large spectral blue shifts relative to the 2PY monomer. Ab initio CIS calculations of the spectral shifts of the different hydrogen-bonded dimers show a linear correlation with experiment. This correlation allows us to identify the R2PI spectra of the weakly populated Watson-Crick and wobble isomers of both 2PY.U and 2PY.T. (3) PW91 density functional calculation of the ground-state binding and dissociation energies De and D0 are in agreement with the assignment of the dominant hydrogen bond isomers of 2PY.U, 2PY.3MU and 2PY.T as the sugar-edge form. For 2PY.U, 2PY.T and 2PY.1MU the measured wobble:Watson-Crick:sugar-edge isomer ratios are in good agreement with the calculated ratios, based on the ab initio dissociation energies and gas-phase statistical mechanics. The Watson-Crick and wobble isomers are thereby determined to be several kcal/mol less strongly bound than the sugar-edge isomers. The 36 observed intermolecular frequencies of the nine different H-bonded isomers give

  6. Code OK3 - An upgraded version of OK2 with beam wobbling function

    NASA Astrophysics Data System (ADS)

    Ogoyski, A. I.; Kawata, S.; Popov, P. H.

    2010-07-01

    structure, including beam wobbling function. Reasons for new version: The code OK3 is based on OK2 [3] and uses the same algorithm with some improvements, the most important one is the beam wobbling function. Summary of revisions:In the code OK3, beams are subdivided on many bunches. The displacement of each bunch center from the initial beam direction is calculated. Code OK3 allows the beamlet number to vary from bunch to bunch. That reduces the calculation error especially in case of very complicated mesh structure with big internal holes. The target temperature rises during the time of energy deposition. Some procedures are improved to perform faster. The energy conservation is checked up on each step of calculation process and corrected if necessary. New procedures included in OK3 Procedure BeamCenterRot( ) rotates the beam axis around the impinging direction of each beam. Procedure BeamletRot( ) rotates the beamlet axes that belong to each beam. Procedure Rotation( ) sets the coordinates of rotated beams and beamlets in chamber and pellet systems. Procedure BeamletOut( ) calculates the lost energy of ions that have not impinged on the target. Procedure TargetT( ) sets the temperature of the target layer of energy deposition during the irradiation process. Procedure ECL( ) checks up the energy conservation law at each step of the energy deposition process. Procedure ECLt( ) performs the final check up of the energy conservation law at the end of deposition process. Modified procedures in OK3 Procedure InitBeam( ): This procedure initializes the beam radius and coefficients A1, A2, A3, A4 and A5 for Gauss distributed beams [2]. It is enlarged in OK3 and can set beams with radii from 1 to 20 mm. Procedure kBunch( ) is modified to allow beamlet number variation from bunch to bunch during the deposition. Procedure ijkSp( ) and procedure Hole( ) are modified to perform faster. Procedure Espl( ) and procedure ChechE( ) are modified to increase the calculation accuracy

  7. Out of the Toolbox: Toddlers Differentiate Wobbly and Wooden Handrails

    ERIC Educational Resources Information Center

    Berger, Sarah E.; Adolph, Karen E.; Lobo, Sharon A.

    2005-01-01

    This study examined whether 16-month-old walking infants take the material composition of a handrail into account when assessing its effectiveness as a tool to augment balance. Infants were encouraged to cross from one platform to another via bridges of various widths (10, 20, 40cm) with either a wobbly (foam or latex) or a wooden handrail…

  8. Uridine treatment protects against neonatal brain damage and long-term cognitive deficits caused by hyperoxia.

    PubMed

    Goren, Bulent; Cakir, Aysen; Sevinc, Cansu; Serter Kocoglu, Sema; Ocalan, Busra; Oy, Ceren; Minbay, Zehra; Kahveci, Nevzat; Alkan, Tulin; Cansev, Mehmet

    2017-12-01

    Exposure to excessive oxygen in survivors of preterm birth is one of the factors that underlie the adverse neurological outcome in later life. Various pathological changes including enhanced apoptotic activity, oxidative stress and inflammation as well as decreased neuronal survival has been demonstrated in animal models of neonatal hyperoxia. The aim of the present study was to investigate the effect of administering uridine, an anti-apoptotic agent, on cellular, molecular and behavioral consequences of hyperoxia-induced brain damage in a neonatal rat model. For five days from birth, rat pups were either subjected continuously to room air (21% oxygen) or hyperoxia (80% oxygen) and received daily intraperitoneal (i.p.) injections of saline (0.9% NaCl) or uridine (500mg/kg). Two-thirds of all pups were sacrificed on postnatal day 5 (P5) in order to investigate apoptotic cell death, myelination and number of surviving neurons. One-thirds of pups were raised through P40 in order to evaluate early reflexes, sensorimotor coordination and cognitive functions followed by investigation of neuron count and myelination. We show that uridine treatment reduces apoptotic cell death and hypomyelination while increasing the number of surviving neurons in hyperoxic pups on P5. In addition, uridine enhances learning and memory performances in periadolescent rats on P40. These data suggest that uridine administered during the course of hyperoxic insult enhances cognitive functions at periadolescent period probably by reducing apoptotic cell death and preventing hypomyelination during the neonatal period in a rat model of hyperoxia-induced brain injury. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. The transport and metabolism of the uridine mononucleotides by rat jejunum in vitro.

    PubMed Central

    Bronk, J R; Hastewell, J G

    1989-01-01

    1. Both uridine 3'-monophosphate (3'-UMP) and uridine 5'-monophosphate (5'-UMP) when perfused through the lumen of isolated rat jejunum gave rise to uracil as the only transported pyrimidine appearing in the serosal medium; neither the nucleotide nor the nucleoside could be detected in the serosal fluid. 2. There was a low level of the nucleoside, uridine, in the luminal fluid after the nucleotide had passed through the jejunal segment. Luminal nucleoside appearance was more marked from the 3' form of the nucleotide. 3. The hydrolysis of the nucleotides to the nucleoside form occurred via a brush-border membrane enzyme, which had the same maximal velocity (Vmax) for the two nucleotides (699 +/- 35 and 747 +/- 10 nmol min-1 (mg protein)-1 for 3'-UMP and 5'-UMP, respectively) but a different Michaelis constant (Km) so that 3'-UMP (Km = 58 +/- 3 microM) hydrolysis is favoured over 5'-UMP hydrolysis (Km = 108 +/- microM) at lower concentrations. 4. At 0.05 mM, luminal 3'-UMP gave rise to a higher rate of serosal uracil appearance than luminal 5'-UMP, but at higher luminal concentrations (0.1-0.2 mM) the rate of serosal uracil appearance was the same from both nucleotides. 5. The transmural transport of uracil from the uridine mononucleotides is discussed with reference to the metabolism and compartmentalization of the small intestine responsible for the appearance of the free pyrimidine in the serosal fluid. PMID:2778724

  10. tRNA wobble modifications and protein homeostasis

    PubMed Central

    Ranjan, Namit; Rodnina, Marina V.

    2016-01-01

    Abstract tRNA is a central component of the protein synthesis machinery in the cell. In living cells, tRNAs undergo numerous post-transcriptional modifications. In particular, modifications at the anticodon loop play an important role in ensuring efficient protein synthesis, maintaining protein homeostasis, and helping cell adaptation and survival. Hypo-modification of the wobble position of the tRNA anticodon loop is of particular relevance for translation regulation and is implicated in various human diseases. In this review we summarize recent evidence of how methyl and thiol modifications in eukaryotic tRNA at position 34 affect cellular fitness and modulate regulatory circuits at normal conditions and under stress. PMID:27335723

  11. Novel base-pairing interactions at the tRNA wobble position crucial for accurate reading of the genetic code

    NASA Astrophysics Data System (ADS)

    Rozov, Alexey; Demeshkina, Natalia; Khusainov, Iskander; Westhof, Eric; Yusupov, Marat; Yusupova, Gulnara

    2016-01-01

    Posttranscriptional modifications at the wobble position of transfer RNAs play a substantial role in deciphering the degenerate genetic code on the ribosome. The number and variety of modifications suggest different mechanisms of action during messenger RNA decoding, of which only a few were described so far. Here, on the basis of several 70S ribosome complex X-ray structures, we demonstrate how Escherichia coli tRNALysUUU with hypermodified 5-methylaminomethyl-2-thiouridine (mnm5s2U) at the wobble position discriminates between cognate codons AAA and AAG, and near-cognate stop codon UAA or isoleucine codon AUA, with which it forms pyrimidine-pyrimidine mismatches. We show that mnm5s2U forms an unusual pair with guanosine at the wobble position that expands general knowledge on the degeneracy of the genetic code and specifies a powerful role of tRNA modifications in translation. Our models consolidate the translational fidelity mechanism proposed previously where the steric complementarity and shape acceptance dominate the decoding mechanism.

  12. Novel base-pairing interactions at the tRNA wobble position crucial for accurate reading of the genetic code.

    PubMed

    Rozov, Alexey; Demeshkina, Natalia; Khusainov, Iskander; Westhof, Eric; Yusupov, Marat; Yusupova, Gulnara

    2016-01-21

    Posttranscriptional modifications at the wobble position of transfer RNAs play a substantial role in deciphering the degenerate genetic code on the ribosome. The number and variety of modifications suggest different mechanisms of action during messenger RNA decoding, of which only a few were described so far. Here, on the basis of several 70S ribosome complex X-ray structures, we demonstrate how Escherichia coli tRNA(Lys)(UUU) with hypermodified 5-methylaminomethyl-2-thiouridine (mnm(5)s(2)U) at the wobble position discriminates between cognate codons AAA and AAG, and near-cognate stop codon UAA or isoleucine codon AUA, with which it forms pyrimidine-pyrimidine mismatches. We show that mnm(5)s(2)U forms an unusual pair with guanosine at the wobble position that expands general knowledge on the degeneracy of the genetic code and specifies a powerful role of tRNA modifications in translation. Our models consolidate the translational fidelity mechanism proposed previously where the steric complementarity and shape acceptance dominate the decoding mechanism.

  13. Process Parameter Optimization for Wobbling Laser Spot Welding of Ti6Al4V Alloy

    NASA Astrophysics Data System (ADS)

    Vakili-Farahani, F.; Lungershausen, J.; Wasmer, K.

    Laser beam welding (LBW) coupled with "wobble effect" (fast oscillation of the laser beam) is very promising for high precision micro-joining industry. For this process, similarly to the conventional LBW, the laser welding process parameters play a very significant role in determining the quality of a weld joint. Consequently, four process parameters (laser power, wobble frequency, number of rotations within a single laser pulse and focused position) and 5 responses (penetration, width, heat affected zone (HAZ), area of the fusion zone, area of HAZ and hardness) were investigated for spot welding of Ti6Al4V alloy (grade 5) using a design of experiments (DoE) approach. This paper presents experimental results showing the effects of variating the considered most important process parameters on the spot weld quality of Ti6Al4V alloy. Semi-empirical mathematical models were developed to correlate laser welding parameters to each of the measured weld responses. Adequacies of the models were then examined by various methods such as ANOVA. These models not only allows a better understanding of the wobble laser welding process and predict the process performance but also determines optimal process parameters. Therefore, optimal combination of process parameters was determined considering certain quality criteria set.

  14. Emergency use of uridine triacetate for the prevention and treatment of life‐threatening 5‐fluorouracil and capecitabine toxicity

    PubMed Central

    Saif, Muhammad Wasif; El‐Rayes, Bassel F.; Fakih, Marwan G.; Cartwright, Thomas H.; Posey, James A.; King, Thomas R.; von Borstel, Reid W.; Bamat, Michael K.

    2016-01-01

    BACKGROUND Increased susceptibility to 5‐fluorouracil (5‐FU)/capecitabine can lead to rapidly occurring toxicity caused by impaired clearance, dihydropyrimidine dehydrogenase deficiency, and other genetic variations in the enzymes that metabolize 5‐FU. Life‐threatening 5‐FU overdoses occur because of infusion pump errors, dosage miscalculations, and accidental or suicidal ingestion of capecitabine. Uridine triacetate (Vistogard) was approved in 2015 for adult and pediatric patients who exhibit early‐onset severe or life‐threatening 5‐FU/capecitabine toxicities or present with an overdose. Uridine triacetate delivers high concentrations of uridine, which competes with toxic 5‐FU metabolites. METHODS In 2 open‐label clinical studies, patients who presented with a 5‐FU/capecitabine overdose or an early onset of severe toxicities were treated. Patients received uridine triacetate as soon as possible (most within the first 96 hours after 5‐FU/capecitabine). Outcomes included survival, resumption of chemotherapy, and safety. Their survival was compared with the survival of a historical cohort of overdose patients who received only supportive care. RESULTS A total of 137 of 142 overdose patients (96%) treated with uridine triacetate survived and had a rapid reversal of severe acute cardiotoxicity and neurotoxicity; in addition, mucositis and leukopenia were prevented, or the patients recovered from them. In the historical cohort, 21 of 25 patients (84%) died. Among the 141 uridine triacetate–treated overdose patients with a diagnosis of cancer (the noncancer patients included 6 intentional or accidental pediatric overdoses), 53 resumed chemotherapy in < 30 days (median time after 5‐FU, 19.6 days), and this indicated a rapid recovery from toxicity. Adverse reactions in patients receiving uridine triacetate included vomiting (8.1%), nausea (4.6%), and diarrhea (3.5%). CONCLUSIONS In these studies, uridine triacetate was a safe and effective

  15. Uridine monophosphate synthetase enables eukaryotic de novo NAD+ biosynthesis from quinolinic acid.

    PubMed

    McReynolds, Melanie R; Wang, Wenqing; Holleran, Lauren M; Hanna-Rose, Wendy

    2017-07-07

    NAD + biosynthesis is an attractive and promising therapeutic target for influencing health span and obesity-related phenotypes as well as tumor growth. Full and effective use of this target for therapeutic benefit requires a complete understanding of NAD + biosynthetic pathways. Here, we report a previously unrecognized role for a conserved phosphoribosyltransferase in NAD + biosynthesis. Because a required quinolinic acid phosphoribosyltransferase (QPRTase) is not encoded in its genome, Caenorhabditis elegans are reported to lack a de novo NAD + biosynthetic pathway. However, all the genes of the kynurenine pathway required for quinolinic acid (QA) production from tryptophan are present. Thus, we investigated the presence of de novo NAD + biosynthesis in this organism. By combining isotope-tracing and genetic experiments, we have demonstrated the presence of an intact de novo biosynthesis pathway for NAD + from tryptophan via QA, highlighting the functional conservation of this important biosynthetic activity. Supplementation with kynurenine pathway intermediates also boosted NAD + levels and partially reversed NAD + -dependent phenotypes caused by mutation of pnc-1 , which encodes a nicotinamidase required for NAD + salvage biosynthesis, demonstrating contribution of de novo synthesis to NAD + homeostasis. By investigating candidate phosphoribosyltransferase genes in the genome, we determined that the conserved uridine monophosphate phosphoribosyltransferase (UMPS), which acts in pyrimidine biosynthesis, is required for NAD + biosynthesis in place of the missing QPRTase. We suggest that similar underground metabolic activity of UMPS may function in other organisms. This mechanism for NAD + biosynthesis creates novel possibilities for manipulating NAD + biosynthetic pathways, which is key for the future of therapeutics. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Metabolomics profiles delineate uridine deficiency contributes to mitochondria-mediated apoptosis induced by celastrol in human acute promyelocytic leukemia cells

    PubMed Central

    Li, Lei; Huan, Fei; Li, Aiping; Liu, Yanqing; Xia, Yankai; Duan, Jin-ao; Ma, Shiping

    2016-01-01

    Celastrol, extracted from “Thunder of God Vine”, is a promising anti-cancer natural product. However, its effect on acute promyelocytic leukemia (APL) and underlying molecular mechanism are poorly understood. The purpose of this study was to explore its effect on APL and underlying mechanism based on metabolomics. Firstly, multiple assays indicated that celastrol could induce apoptosis of APL cells via p53-activated mitochondrial pathway. Secondly, unbiased metabolomics revealed that uridine was the most notable changed metabolite. Further study verified that uridine could reverse the apoptosis induced by celastrol. The decreased uridine was caused by suppressing the expression of gene encoding Dihydroorotate dehydrogenase, whose inhibitor could also induce apoptosis of APL cells. At last, mouse model confirmed that celastrol inhibited tumor growth through enhanced apoptosis. Celastrol could also decrease uridine and DHODH protein level in tumor tissues. Our in vivo study also indicated that celastrol had no systemic toxicity at pharmacological dose (2 mg/kg, i.p., 21 days). Altogether, our metabolomics study firstly reveals that uridine deficiency contributes to mitochondrial apoptosis induced by celastrol in APL cells. Celastrol shows great potential for the treatment of APL. PMID:27374097

  17. Combined uridine and choline administration improves cognitive deficits in spontaneously hypertensive rats.

    PubMed

    De Bruin, N M W J; Kiliaan, A J; De Wilde, M C; Broersen, L M

    2003-07-01

    Rationale. Hypertension is considered a risk factor for the development of cognitive disorders, because of its negative effects on cerebral vasculature and blood flow. Genetically induced hypertension in rats has been associated with a range of cognitive impairments. Therefore, spontaneously hypertensive rats (SHR) can potentially be used as a model for cognitive deficits in human subjects. Consecutively, it can be determined whether certain food components can improve cognition in these rats. Objective. The present study aimed to determine whether SHR display specific deficits in attention, learning, and memory function. Additionally, effects of chronic uridine and choline administration were studied. Methods. 5-7 months old SHR were compared with normotensive Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats. (a) The operant delayed non-matching-to-position (DNMTP) test was used to study short-term memory function. (b) The five-choice serial reaction time (5-CSRT) task was used to assess selective visual attention processes. (c) Finally, the Morris water maze (MWM) acquisition was used as a measure for spatial learning and mnemonic capabilities. Results. (1) SHR exhibited significantly impaired performance in the 5-CSRT test in comparison with the two other rat strains. Both the SHR and WKY showed deficits in spatial learning when compared with the SD rats. (2) Uridine and choline supplementation normalized performance of SHR in the 5-CSRT test. (3) In addition, uridine and choline treatment improved MWM acquisition in both WKY and SHR rats. Conclusion. The present results show that the SHR have a deficiency in visual selective attention and spatial learning. Therefore, the SHR may provide an interesting model in the screening of substances with therapeutic potential for treatment of cognitive disorders. A combination of uridine and choline administration improved selective attention and spatial learning in SHR.

  18. Improvement of uridine production of Bacillus subtilis by atmospheric and room temperature plasma mutagenesis and high-throughput screening

    PubMed Central

    Li, Guoliang; Yuan, Hui; Zhang, Hongchao; Li, Yanjun; Xie, Xixian; Chen, Ning

    2017-01-01

    In the present study, a novel breeding strategy of atmospheric and room temperature plasma (ARTP) mutagenesis was used to improve the uridine production of engineered Bacillus subtilis TD12np. A high-throughput screening method was established using both resistant plates and 96-well microplates to select the ideal mutants with diverse phenotypes. Mutant F126 accumulated 5.7 and 30.3 g/L uridine after 30 h in shake-flask and 48 h in fed-batch fermentation, respectively, which represented a 4.4- and 8.7-fold increase over the parent strain. Sequence analysis of the pyrimidine nucleotide biosynthetic operon in the representative mutants showed that proline 1016 and glutamate 949 in the large subunit of B. subtilis carbamoyl phosphate synthetase were of importance for the allosteric regulation caused by uridine 5′-monophosphate. The proposed mutation method with efficient high-throughput screening assay was proved to be an appropriate strategy to obtain uridine-overproducing strain. PMID:28472077

  19. Improvement of uridine production of Bacillus subtilis by atmospheric and room temperature plasma mutagenesis and high-throughput screening.

    PubMed

    Fan, Xiaoguang; Wu, Heyun; Li, Guoliang; Yuan, Hui; Zhang, Hongchao; Li, Yanjun; Xie, Xixian; Chen, Ning

    2017-01-01

    In the present study, a novel breeding strategy of atmospheric and room temperature plasma (ARTP) mutagenesis was used to improve the uridine production of engineered Bacillus subtilis TD12np. A high-throughput screening method was established using both resistant plates and 96-well microplates to select the ideal mutants with diverse phenotypes. Mutant F126 accumulated 5.7 and 30.3 g/L uridine after 30 h in shake-flask and 48 h in fed-batch fermentation, respectively, which represented a 4.4- and 8.7-fold increase over the parent strain. Sequence analysis of the pyrimidine nucleotide biosynthetic operon in the representative mutants showed that proline 1016 and glutamate 949 in the large subunit of B. subtilis carbamoyl phosphate synthetase were of importance for the allosteric regulation caused by uridine 5'-monophosphate. The proposed mutation method with efficient high-throughput screening assay was proved to be an appropriate strategy to obtain uridine-overproducing strain.

  20. Semiclassical unified description of wobbling motion in even-even and even-odd nuclei

    NASA Astrophysics Data System (ADS)

    Raduta, A. A.; Poenaru, R.; Ixaru, L. Gr.

    2017-11-01

    A unitary description for wobbling motion in even-even and even-odd nuclei is presented. In both cases compact formulas for wobbling frequencies are derived. The accuracy of the harmonic approximation is studied for the yrast as well as for the excited bands in the even-even case. Important results for the structure of the wave function and its behavior inside the two wells of the potential energy function corresponding to the Bargmann representation are pointed out. Applications to 158Er and 163Lu reveal a very good agreement with available data. Indeed, the yrast energy levels in the even-even case and the first four triaxial superdeformed bands, TSD1, TSD2, TSD3, and TSD4, are realistically described. Also, the results agree with the data for the E 2 and M 1 intra- as well as interband transitions. Perspectives for the formalism development and an extensive application to several nuclei from various regions of the nuclides chart are presented.

  1. Novel base-pairing interactions at the tRNA wobble position crucial for accurate reading of the genetic code

    PubMed Central

    Rozov, Alexey; Demeshkina, Natalia; Khusainov, Iskander; Westhof, Eric; Yusupov, Marat; Yusupova, Gulnara

    2016-01-01

    Posttranscriptional modifications at the wobble position of transfer RNAs play a substantial role in deciphering the degenerate genetic code on the ribosome. The number and variety of modifications suggest different mechanisms of action during messenger RNA decoding, of which only a few were described so far. Here, on the basis of several 70S ribosome complex X-ray structures, we demonstrate how Escherichia coli tRNALysUUU with hypermodified 5-methylaminomethyl-2-thiouridine (mnm5s2U) at the wobble position discriminates between cognate codons AAA and AAG, and near-cognate stop codon UAA or isoleucine codon AUA, with which it forms pyrimidine–pyrimidine mismatches. We show that mnm5s2U forms an unusual pair with guanosine at the wobble position that expands general knowledge on the degeneracy of the genetic code and specifies a powerful role of tRNA modifications in translation. Our models consolidate the translational fidelity mechanism proposed previously where the steric complementarity and shape acceptance dominate the decoding mechanism. PMID:26791911

  2. tRNAomics: tRNA gene copy number variation and codon use provide bioinformatic evidence of a new anticodon:codon wobble pair in a eukaryote

    PubMed Central

    Iben, James R.; Maraia, Richard J.

    2012-01-01

    tRNA genes are interspersed throughout eukaryotic DNA, contributing to genome architecture and evolution in addition to translation of the transcriptome. Codon use correlates with tRNA gene copy number in noncomplex organisms including yeasts. Synonymous codons impact translation with various outcomes, dependent on relative tRNA abundances. Availability of whole-genome sequences allowed us to examine tRNA gene copy number variation (tgCNV) and codon use in four Schizosaccharomyces species and Saccharomyces cerevisiae. tRNA gene numbers vary from 171 to 322 in the four Schizosaccharomyces despite very high similarity in other features of their genomes. In addition, we performed whole-genome sequencing of several related laboratory strains of Schizosaccharomyces pombe and found tgCNV at a cluster of tRNA genes. We examined for the first time effects of wobble rules on correlation of tRNA gene number and codon use and showed improvement for S. cerevisiae and three of the Schizosaccharomyces species. In contrast, correlation in Schizosaccharomyces japonicus is poor due to markedly divergent tRNA gene content, and much worsened by the wobble rules. In japonicus, some tRNA iso-acceptor genes are absent and others are greatly reduced relative to the other yeasts, while genes for synonymous wobble iso-acceptors are amplified, indicating wobble use not apparent in any other eukaryote. We identified a subset of japonicus-specific wobbles that improves correlation of codon use and tRNA gene content in japonicus. We conclude that tgCNV is high among Schizo species and occurs in related laboratory strains of S. pombe (and expectedly other species), and tRNAome-codon analyses can provide insight into species-specific wobble decoding. PMID:22586155

  3. Modified 5-fluorouracil: Uridine phosphorylase inhibitor

    NASA Astrophysics Data System (ADS)

    Lashkov, A. A.; Shchekotikhin, A. A.; Shtil, A. A.; Sotnichenko, S. E.; Mikhailov, A. M.

    2016-09-01

    5-Fluorouracil (5-FU) is a medication widely used in chemotherapy to treat various types of cancer. Being a substrate for the reverse reaction catalyzed by uridine phosphorylase (UPase), 5-FU serves as a promising prototype molecule (molecular scaffold) for the design of a selective UPase inhibitor that enhances the antitumor activity of 5-FU and exhibits intrinsic cytostatic effects on cancer cells. The chemical formula of the new compound, which binds to the uracil-binding site and, in the presence of a phosphate anion, to the phosphate-binding site of UPase, is proposed and investigated by molecular simulation methods.

  4. Development and user evaluation of a virtual rehabilitation system for wobble board balance training.

    PubMed

    Fitzgerald, Diarmaid; Trakarnratanakul, Nanthana; Dunne, Lucy; Smyth, Barry; Caulfield, Brian

    2008-01-01

    We have developed a prototype virtual reality-based balance training system using a single inertial orientation sensor attached to the upper surface of a wobble board. This input device has been interfaced with Neverball, an open source computer game to create the balance training platform. Users can exercise with the system by standing on the wobble board and tilting it in different directions to control an on-screen environment. We have also developed a customized instruction manual to use when setting up the system. To evaluate the usability our prototype system we undertook a user evaluation study with twelve healthy novice participants. Participants were required to assemble the system using an instruction manual and then perform balance exercises with the system. Following this period of exercise VRUSE, a usability evaluation questionnaire, was completed by participants. Results indicated a high level of usability in all categories evaluated.

  5. Ambient neutron dose equivalent during proton therapy using wobbling scanning system: Measurements and calculations

    NASA Astrophysics Data System (ADS)

    Lin, Yung-Chieh; Lee, Chung-Chi; Chao, Tsi-Chian; Tsai, Hui-Yu

    2017-11-01

    Neutron production is a concern in proton therapy, particularly in scattering proton beam delivery systems. Despite this fact, little is known about the effects of secondary neutron exposure around wobbling scattered proton treatment nozzles. The objective of this study was to estimate the neutron dose level resulting from the use of a wobbling scattered proton treatment unit. We applied the Monte Carlo method for predict the ambient neutron dose equivalent, H*(10), per absorbed dose at the treatment isocenter, D, in the proton therapy center of Chang Gung Memorial Hospital, Linkou, Taiwan. For a 190-MeV proton beam, H* (10) / D values typically decreased with the distance from the isocenter, being 1.106 mSv/Gy at the isocenter versus 0.112 mSv/Gy at a distance of 150 cm from the isocenter. The H* (10) / D values generally decreased as the neutron receptors moved away from the isocenter, and increased when the angle from the initial beam axis increased. The ambient neutron dose equivalents were observed to be slightly lower in the direction of multileaf collimator movement. For radiation protection, the central axis of a proton-treated patient is suggested to be at the 0° angle of the beam. If the beam direction at the 90° angle is necessary, the patient axis is suggested to be along with the direction of MLC movement. Our study provides the neutron dose level and neutron energy fluence for the first wobbling proton system at the proton therapy center of Chang Gung Memorial Hospital.

  6. Photoelectron and computational studies of the copper-nucleoside anionic complexes, Cu(-)(cytidine) and Cu(-)(uridine).

    PubMed

    Li, Xiang; Ko, Yeon-Jae; Wang, Haopeng; Bowen, Kit H; Guevara-García, Alfredo; Martínez, Ana

    2011-02-07

    The copper-nucleoside anions, Cu(-)(cytidine) and Cu(-)(uridine), have been generated in the gas phase and studied by both experimental (anion photoelectron spectroscopy) and theoretical (density functional calculations) methods. The photoelectron spectra of both systems are dominated by single, intense, and relatively narrow peaks. These peaks are centered at 2.63 and 2.71 eV for Cu(-)(cytidine) and Cu(-)(uridine), respectively. According to our calculations, Cu(-)(cytidine) and Cu(-)(uridine) species with these peak center [vertical detachment energy (VDE)] values correspond to structures in which copper atomic anions are bound to the sugar portions of their corresponding nucleosides largely through electrostatic interactions; the observed species are anion-molecule complexes. The combination of experiment and theory also reveal the presence of a slightly higher energy, anion-molecule complex isomer in the case of the Cu(-)(cytidine). Furthermore, our calculations found that chemically bond isomers of these species are much more stable than their anion-molecule complex counterparts, but since their calculated VDE values are larger than the photon energy used in these experiments, they were not observed.

  7. Photoelectron and computational studies of the copper-nucleoside anionic complexes, Cu-(cytidine) and Cu-(uridine)

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Ko, Yeon-Jae; Wang, Haopeng; Bowen, Kit H.; Guevara-García, Alfredo; Martínez, Ana

    2011-02-01

    The copper-nucleoside anions, Cu-(cytidine) and Cu-(uridine), have been generated in the gas phase and studied by both experimental (anion photoelectron spectroscopy) and theoretical (density functional calculations) methods. The photoelectron spectra of both systems are dominated by single, intense, and relatively narrow peaks. These peaks are centered at 2.63 and 2.71 eV for Cu-(cytidine) and Cu-(uridine), respectively. According to our calculations, Cu-(cytidine) and Cu-(uridine) species with these peak center [vertical detachment energy (VDE)] values correspond to structures in which copper atomic anions are bound to the sugar portions of their corresponding nucleosides largely through electrostatic interactions; the observed species are anion-molecule complexes. The combination of experiment and theory also reveal the presence of a slightly higher energy, anion-molecule complex isomer in the case of the Cu-(cytidine). Furthermore, our calculations found that chemically bond isomers of these species are much more stable than their anion-molecule complex counterparts, but since their calculated VDE values are larger than the photon energy used in these experiments, they were not observed.

  8. Immunochemical characterization of the anti-RNA antibodies found in scleroderma and systemic lupus erythematosus. II. Reactivity with hsa-coupled, uridine-containing, monophosphoric ribodinucleotides.

    PubMed Central

    Alarcón-Segovia, D; Fishbein, E; Estrada-Parra, S; García-Ortigoza, E

    1976-01-01

    Sera from patients with scleroderma have been found to have anti-RNA antibodies which react with human serum albumin (HSA)-coupled uridine and uridine monophosphate (UMP) and are inhibited by uracil, uridine and UMP. Scleroderma sera react uniformly with 5'-polyuridylic acid (poly(U)) and fail to react with polyadenylic, polyuridylic acid poly(A) - poly(U)) which is also indicative of their uracil specificity. Anti-RNA antibodies found in systemic lupus erythematosus (SLE) are immunochemically different from those found in scleroderma in that, instead of being uniformly specific to uracil, they are markedly heterogeneous and may react with uracil, uridine and/or UMP. SLE sera frequently react with poly(A) - poly(U), indicating also their ability to recognize the double helical structure of double-stranded RNA. Thirty-seven scleroderma and thirty-four SLE sera from as many patients with either of these conditions were tested against HSA-coupled, uridine-containing monophosphoric dinucleotides in an attempt to characterize further their anti-RNA antibodies. Scleroderma sera were found to react primarily with dinucleotides in which uridine was the base proximal to the carrier protein and, except for sera that also contained antibodies to adenosine which reacted with UpA, they failed to react with dinucleotides in which uridine was in a terminal position only. Reaction with dinucleotides in which uridine was proximal to the carrier protein could be inhibited by uracil but not by the corresponding terminal base. Some lupus sera were found to react with both dinucleotides that contain the same bases in opposite sequence, e.g. ApU and UpA, while others were found to react with only one of the sequences. They were also found to react more frequently with dinucleotides in which HSA was coupled to a base other than uridine, suggesting that the reaction is primarily due to anti-DNA antibodies. Because immunization with dinucleotides coupled to protein prepared by the same

  9. Detection of RNA nucleoside modifications with the uridine-specific ribonuclease MC1 from Momordica charantia

    PubMed Central

    Addepalli, Balasubrahmanym; Lesner, Nicholas P.; Limbach, Patrick A.

    2015-01-01

    A codon-optimized recombinant ribonuclease, MC1 is characterized for its uridine-specific cleavage ability to map nucleoside modifications in RNA. The published MC1 amino acid sequence, as noted in a previous study, was used as a template to construct a synthetic gene with a natural codon bias favoring expression in Escherichia coli. Following optimization of various expression conditions, the active recombinant ribonuclease was successfully purified as a C-terminal His-tag fusion protein from E. coli [Rosetta 2(DE3)] cells. The isolated protein was tested for its ribonuclease activity against oligoribonucleotides and commercially available E. coli tRNATyr I. Analysis of MC1 digestion products by ion-pairing reverse phase liquid-chromatography coupled with mass spectrometry (IP-RP-LC-MS) revealed enzymatic cleavage of RNA at the 5′-termini of uridine and pseudouridine, but cleavage was absent if the uridine was chemically modified or preceded by a nucleoside with a bulky modification. Furthermore, the utility of this enzyme to generate complementary digestion products to other common endonucleases, such as RNase T1, which enables the unambiguous mapping of modified residues in RNA is demonstrated. PMID:26221047

  10. Restorative effects of uridine plus docosahexaenoic acid in a rat model of Parkinson's disease.

    PubMed

    Cansev, Mehmet; Ulus, Ismail H; Wang, Lei; Maher, Timothy J; Wurtman, Richard J

    2008-11-01

    Administering uridine-5'-monophosphate (UMP) and docosahexaenoic acid (DHA) increases synaptic membranes (as characterized by pre- and post-synaptic proteins) and dendritic spines in rodents. We examined their effects on rotational behavior and dopaminergic markers in rats with partial unilateral 6-hydroxydopamine (6-OHDA)-induced striatal lesions. Rats receiving UMP, DHA, both, or neither, daily, and intrastriatal 6-OHDA 3 days after treatment onset, were tested for d-amphetamine-induced rotational behavior and dopaminergic markers after 24 and 28 days, respectively. UMP/DHA treatment reduced ipsilateral rotations by 57% and significantly elevated striatal dopamine, tyrosine hydroxylase (TH) activity, TH protein and synapsin-1 on the lesioned side. Hence, giving uridine and DHA may partially restore dopaminergic neurotransmission in this model of Parkinson's disease.

  11. Reaction of uridine diphosphate galactose 4-epimerase with a suicide inactivator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flentke, G.R.; Frey, P.A.

    UDPgalactose 4-epimerase from Escherichia coli is rapidly inactivated by the compounds uridine 5{prime}-diphosphate chloroacetol (UDC) and uridine 5{prime}-diphosphate bromoacetol (UCB). Both UDC and UDB inactivate the enzyme in neutral solution concomitant with the appearance of chromophores absorbing maximally at 325 and 328 nm, respectively. The reaction of UDC with the enzyme follows saturation kinetics characterized by a K{sub D} of 0.110 mM and k{sub inact} of 0.84 min{sup {minus}1} at pH 8.5 and ionic strength 0.2 M. The inactivation by UDC is competitively inhibited by competitive inhibitors of UDPgalactose 4-epimerase, and it is accompanied by the tight but noncovalent bindingmore » of UDC to the enzyme in a stoichiometry of 1 mol of UDC/mol of enzyme dimer, corresponding to 1 mol of UDC/mol of enzyme-bound NAD{sup +}. The inactivation of epimerase by uridine 5{prime}-diphosphate ({sup 2}H{sub 2})chloroacetol proceeds with a primary kinetic isotope effect (k{sub H}/k{sub D}) of 1.4. The inactivation mechanism is proposed to involve a minimum of three steps: (a) reversible binding of UDC to the active site of UDPgalactose 4-epimerase; (b) enolization of the chloroacetol moiety of enzyme-bound UDC, catalyzed by an enzymic general base at the active site; (c) alkylation of the nicotinamide ring of NAD{sup +} at the active site by the chloroacetol enolate. The resulting adduct between UDC and NAD{sup +} is proposed to be the chromophore with {lambda}{sub max} at 325 nm. The enzymic general base required to facilitate proton transfer in redox catalysis by this enzyme may be the general base that facilitates enolization of the chloroacetol moiety of UDC in the inactivation reaction.« less

  12. Comparison of tetrazolium colorimetric and [3H]-uridine assays for in vitro chemosensitivity testing.

    PubMed

    Ford, C H; Richardson, V J; Tsaltas, G

    1989-01-01

    We have routinely used a [3H]-uridine microplate assay for assessing chemosensitivity. A colorimetric assay with the advantages of safety, cost and simplicity has previously been described and relies on the ability of living cells to reduce a soluble tetrazolium salt, 3-4,5-dimethylthiazol-2,5-diphenyl-tetrazolium bromide (MMT), into an insoluble formazan precipitate. We compared the chemosensitivity of 14 human tumour cell lines of colonic, lung and cervical carcinoma origin to doxorubicin, vindesine or vindesine immunoconjugates in both the [3H]-uridine assay and a modified MTT assay to evaluate whether we could change to the non-radiolabelled method. Correlation between the concentration of drug causing 50% inhibition of cell growth (IC50) for these agents between the two assays was very poor. However, taking account of recent reports in the literature, we modified the MTT assay by removing serum-containing medium and using dimethyl sulphoxide to solubilise the formazan precipitate. This considerably improved the correlation between the assays for doxorubicin (r = 0.871; P = 0.001) and vindesine (r = 0.981; P less than 0.001). Our data indicates that the MTT assay can be used to replace the [3H]-uridine assay for chemosensitivity screening, but further modifications are necessary to improve the sensitivity and decrease the problem of cell loss after washing, which was noted with some adherent cell lines.

  13. Astrocytoma in an African hedgehog (Atelerix albiventris) suspected wobbly hedgehog syndrome.

    PubMed

    Nakata, Makoto; Miwa, Yasutsugu; Itou, Takuya; Uchida, Kazuyuki; Nakayama, Hiroyuki; Sakai, Takeo

    2011-10-01

    A 28-month-old African hedgehog was referred to our hospital with progressive tetraparesis. On the first presentation, the hedgehog was suspected as having wobbly hedgehog syndrome (WHS) and the animal was treated with medication and rehabilitation. The animal died 22 days after onset. Pathological examination revealed that the animal was involved in astrocytoma between the medulla oblongata and the spinal cord (C1). This report indicates that a primary central nervous system tumor should be considered as one of the differential diagnoses for hedgehogs presenting with progressive paresis, together with WHS.

  14. Black Hole with Wobbling Disk Artist Concept

    NASA Image and Video Library

    2016-07-12

    This artist's impression depicts the accretion disc surrounding a black hole, in which the inner region of the disc precesses. "Precession" means that the orbit of material surrounding the black hole changes orientation around the central object. In these three views, the precessing inner disc shines high-energy radiation that strikes the matter in the surrounding accretion disc. This causes the iron atoms in that disc to emit X-rays, depicted as the glow on the accretion disc to the right (in view a), to the front (in view b) and to the left (in view c) (see Figure 1). In a study published in July 2016, astronomers used data from ESA's XMM-Newton X-ray Observatory and NASA's NuSTAR telescope to measure this "wobble" in X-ray emission from excited iron atoms. Scientists interpreted this as evidence for the Lense-Thirring effect -- a name for the precession phenomenon -- in the strong gravitational field of a black hole. http://photojournal.jpl.nasa.gov/catalog/PIA20697

  15. Uridine Nucleoside Thiation: Gas-Phase Structures and Energetics

    NASA Astrophysics Data System (ADS)

    Hamlow, Lucas; Lee, Justin; Rodgers, M. T.; Berden, Giel; Oomens, Jos

    2016-06-01

    The naturally occurring thiated uridine nucleosides, 4-thiouridine (s4Urd) and 2-thiouridine (s2Urd), play important roles in the function and analysis of a variety of RNAs. 2-Thiouridine and its C5 modified analogues are commonly found in tRNAs and are believed to play an important role in codon recognition possibly due to their different structure, which has been shown by NMR to be predominantly C3'-endo. 2-Thiouridine may also play an important role in facilitating nonenzymatic RNA replication and transcription. 4-Thiouridine is a commonly used photoactivatable crosslinker that is often used to study RNA-RNA and RNA-protein cross-linking behavior. Differences in the base pairing between uracil and 4-thiouracil with adenine and guanine are an important factor in their role as a cross linker. The photoactivity of s4Urd may also aid in preventing near-UV lethality in cells. An understanding of their intrinsic structure in the gas-phase may help further elucidate the roles these modified nucleosides play in the regulation of RNAs. In this work, infrared multiple photon dissociation (IRMPD) action spectra of the protonated forms of s2Urd and s4Urd were collected in the IR fingerprint region. Structural information is determined by comparison with theoretical linear IR spectra generated from density functional theory calculations using molecular modeling to generate low-energy candidate structures. Present results are compared with analogous results for the protonated forms of uridine and 2'-deoxyuridine as well as solution phase NMR data and crystal structures.

  16. Short-term administration of uridine increases brain membrane phospholipids precursors in healthy adults: a 31-phosphorus magnetic resonance spectroscopy study at 4T

    PubMed Central

    Agarwal, Nivedita; Sung, Young-Hoon; Jensen, J Eric; daCunha, Grace; Harper, David; Olson, David; Renshaw, Perry F

    2010-01-01

    Objectives Altered metabolism of membrane phospholipids has been implicated in bipolar disorder. In humans, uridine is an important precursor of cytidine diphosphate (CDP)-choline, which plays a critical role in phospholipid synthesis and is currently being evaluated as a potential treatment for bipolar depression. Methods A total of 17 healthy males (mean age ± SD: 32.73 ± 7.2 years; range: 21.8- 46.4 years) were enrolled in this study. Subjects underwent a 31-phosphorus magnetic resonance spectroscopy (31P-MRS) acquisition at baseline and then again after seven days of either 2 g of uridine or placebo administration. A two-dimensional chemical shift imaging 31P-MRS acquisition collected spectral data from a 4 × 4 cluster of voxels acquired in the axial plane encompassing the subcortical structures as well as frontaltemporal cortical gray and white matter. The slab thickness was 3 cm and the approximate total volume of brain sampled was 432 cm3. The spectra obtained were analyzed using a fully automated in-house fitting algorithm. A population-averaged generalized estimating equation was used to evaluate changes both in phosphomonoesters (PME) [phosphocholine (PCho) and phosphoethanolamine (PEtn)] and phosphodiesters (PDE) [glycerophosphocholine (GPCho) and glycerophosphethanolamine (GPEtn)]. Metabolite ratios were reported with respect to the total integrated 31P resonance area. Results The uridine group had significantly increased total PME and PEtn levels over the one-week period [6.32% and 7.17% for PME and PEtn, respectively (p < 0.001)]. Other metabolite levels such as PCho, PDE, GPEtn and GPCho showed no significant changes following either uridine or placebo (all p > 0.05). Conclusions This is the first study to report a direct effect of uridine on membrane phospholipid precursors in healthy adults using 31P-MRS. Sustained administration of uridine appears to increase PME in healthy subjects. Further investigation is required to clarify the effects of

  17. The Methanothermobacter thermautotrophicus ExoIII homologue Mth212 is a DNA uridine endonuclease

    PubMed Central

    Georg, Jens; Schomacher, Lars; Chong, James P. J.; Majerník, Alan I.; Raabe, Monika; Urlaub, Henning; Müller, Sabine; Ciirdaeva, Elena; Kramer, Wilfried; Fritz, Hans-Joachim

    2006-01-01

    The genome of Methanothermobacter thermautotrophicus, as a hitherto unique case, is apparently devoid of genes coding for general uracil DNA glycosylases, the universal mediators of base excision repair following hydrolytic deamination of DNA cytosine residues. We have now identified protein Mth212, a member of the ExoIII family of nucleases, as a possible initiator of DNA uracil repair in this organism. This enzyme, in addition to bearing all the enzymological hallmarks of an ExoIII homologue, is a DNA uridine endonuclease (U-endo) that nicks double-stranded DNA at the 5′-side of a 2′-d-uridine residue, irrespective of the nature of the opposing nucleotide. This type of activity has not been described before; it is absent from the ExoIII homologues of Escherichia coli, Homo sapiens and Methanosarcina mazei, all of which are equipped with uracil DNA repair glycosylases. The U-endo activity of Mth212 is served by the same catalytic center as its AP-endo activity. PMID:17012282

  18. Independent suppression of ribosomal +1 frameshifts by different tRNA anticodon loop modifications.

    PubMed

    Klassen, Roland; Bruch, Alexander; Schaffrath, Raffael

    2017-09-02

    Recently, a role for the anticodon wobble uridine modification 5-methoxycarbonylmethyl-2-thiouridine (mcm 5 s 2 U) has been revealed in the suppression of translational +1 frameshifts in Saccharomyces cerevisiae. Loss of either the mcm 5 U or s 2 U parts of the modification elevated +1 frameshift rates and results obtained with reporters involving a tRNA Lys UUU dependent frameshift site suggested these effects are caused by reduced ribosomal A-site binding of the hypomodified tRNA. Combined loss of mcm 5 U and s 2 U leads to increased ribosome pausing at tRNA Lys UUU dependent codons and synergistic growth defects but effects on +1 frameshift rates remained undefined to this end. We show in here that simultaneous removal of mcm 5 U and s 2 U results in synergistically increased +1 frameshift rates that are suppressible by extra copies of tRNA Lys UUU . Thus, two distinct chemical modifications of the same wobble base independently contribute to reading frame maintenance, loss of which may cause or contribute to observed growth defects. Since the thiolation pathway is sensitive to moderately elevated temperatures in yeast, we observe a heat-induced increase of +1 frameshift rates in wild type cells that depends on the sulfur transfer protein Urm1. Furthermore, we find that temperature-induced frameshifting is kept in check by the dehydration of N6-threonylcarbamoyladenosine (t 6 A) to its cyclic derivative (ct 6 A) at the anticodon adjacent position 37. Since loss of ct 6 A in elp3 or urm1 mutant cells is detrimental for temperature stress resistance we assume that conversion of t 6 A to ct 6 A serves to limit deleterious effects on translational fidelity caused by hypomodified states of wobble uridine bases.

  19. Dietary uridine-5'-monophosphate supplementation increases potassium-evoked dopamine release and promotes neurite outgrowth in aged rats.

    PubMed

    Wang, Lei; Pooler, Amy M; Albrecht, Meredith A; Wurtman, Richard J

    2005-01-01

    Membrane phospholipids like phosphatidylcholine (PC) are required for cellular growth and repair, and specifically for synaptic function. PC synthesis is controlled by cellular levels of its precursor, cytidine-5'-diphosphate choline (CDP-choline), which is produced from cytidine triphosphate (CTP) and phosphocholine. In rat PC12 cells exogenous uridine was shown to elevate intracellular CDP-choline levels, by promoting the synthesis of uridine triphosphate (UTP), which was partly converted to CTP. In such cells uridine also enhanced the neurite outgrowth produced by nerve growth factor (NGF). The present study assessed the effect of dietary supplementation with uridine-5'-monophosphate disodium (UMP-2Na+, an additive in infant milk formulas) on striatal dopamine (DA) release in aged rats. Male Fischer 344 rats consumed either a control diet or one fortified with 2.5% UMP for 6 wk, ad libitum. In vivo microdialysis was then used to measure spontaneous and potassium (K+)-evoked DA release in the right striatum. Potassium (K+)-evoked DA release was significantly greater among UMP-treated rats, i.e., 341+/-21% of basal levels vs. 283+/-9% of basal levels in control rats (p<0.05); basal DA release was unchanged. In general, each animal's K+-evoked DA release correlated with its striatal DA content, measured postmortem. The levels of neurofilament-70 and neurofilament-M proteins, biomarkers of neurite outgrowth, increased to 182+/-25% (p<0.05) and 221+/-34% (p<0.01) of control values, respectively, with UMP consumption. Hence, UMP treatment not only enhances membrane phosphatide production but also can modulate two membrane-dependent processes, neurotransmitter release and neurite outgrowth, in vivo.

  20. Photoelectron and computational studies of the copper-nucleoside anionic complexes, Cu{sup -}(cytidine) and Cu{sup -}(uridine)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li Xiang; Ko, Yeon-Jae; Wang Haopeng

    2011-02-07

    The copper-nucleoside anions, Cu{sup -}(cytidine) and Cu{sup -}(uridine), have been generated in the gas phase and studied by both experimental (anion photoelectron spectroscopy) and theoretical (density functional calculations) methods. The photoelectron spectra of both systems are dominated by single, intense, and relatively narrow peaks. These peaks are centered at 2.63 and 2.71 eV for Cu{sup -}(cytidine) and Cu{sup -}(uridine), respectively. According to our calculations, Cu{sup -}(cytidine) and Cu{sup -}(uridine) species with these peak center [vertical detachment energy (VDE)] values correspond to structures in which copper atomic anions are bound to the sugar portions of their corresponding nucleosides largely through electrostaticmore » interactions; the observed species are anion-molecule complexes. The combination of experiment and theory also reveal the presence of a slightly higher energy, anion-molecule complex isomer in the case of the Cu{sup -}(cytidine). Furthermore, our calculations found that chemically bond isomers of these species are much more stable than their anion-molecule complex counterparts, but since their calculated VDE values are larger than the photon energy used in these experiments, they were not observed.« less

  1. Restorative Effects of Uridine Plus Docosahexaenoic Acid in a Rat Model of Parkinson’s Disease

    PubMed Central

    Cansev, Mehmet; Ulus, Ismail H.; Wang, Lei; Maher, Timothy J.; Wurtman, Richard J.

    2008-01-01

    Summary Administering uridine-5’-monophosphate (UMP) and docosahexaenoic acid (DHA) increases synaptic membranes (as characterized by pre-and post-synaptic proteins) and dendritic spines in rodents. We examined their effects on rotational behavior and dopaminergic markers in rats with partial unilateral 6-hydroxydopamine (6-OHDA)-induced striatal lesions. Rats receiving UMP, DHA, both, or neither, daily, and intrastriatal 6-OHDA 3 days after treatment onset, were tested for d-amphetamine-induced rotational behavior and dopaminergic markers after 24 and 28 days, respectively. UMP/DHA treatment reduced ipsilateral rotations by 57% and significantly elevated striatal dopamine, tyrosine hydroxylase (TH) activity, TH protein and Synapsin-1 on the lesioned side. Hence, giving uridine and DHA may partially restore dopaminergic neurotransmission in this model of Parkinson’s Disease. PMID:18761383

  2. Uridine monophosphate, folic acid and vitamin B12 in patients with symptomatic peripheral entrapment neuropathies.

    PubMed

    Negrão, Luis; Nunes, Paula

    2016-01-01

    Carpal tunnel syndrome is the most common type of peripheral entrapment neuropathy. We performed an exploratory, open-label, multicenter, observational study of 48 patients with peripheral entrapment neuropathy. Patients received a daily capsule of uridine monophosphate, folic acid + vitamin B12 for 2 months and were evaluated using the Pain DETECT questionnaire. The global score for pain decreased from 17.3 ± 5.9 at baseline to 10.3 ± 6.1 at the final evaluation (p < 0.001). Concomitant analgesic and anti-inflammatory treatment was stopped or the dose reduced in 77.4% of patients. Uridine monophosphate + folic acid + vitamin B12 reduced total pain score, intensity and characterization of pain and associated symptoms. These results should be tested in a well-designed, adequately powered randomized controlled trial.

  3. The period and Q of the Chandler wobble

    NASA Technical Reports Server (NTRS)

    Smith, M. L.; Dahlen, F. A.

    1981-01-01

    The calculation of the theoretical period of the Chandler wobble is extended to account for the non-hydrostatic portion of the earth's equatorial bulge and the effect of the fluid core upon the lengthening of the period due to the pole tide. The theoretical period of a realistic perfectly elastic earth with an equilibrium pole tide is found to be 426.7 sidereal days, which is 8.5 days shorter than the observed period of 435.2 days. Using Rayleigh's principle for a rotating earth, this discrepancy is exploited together with the observed Chandler Q to place constraints on the frequency dependence of mantle anelasticity. In all cases these limits arise from exceeding the 68 percent confidence limits of + or - 2.6 days in the observed period. Since slight departures from an equilibrium pole tide affect the Q much more strongly than the period, these limits are believed to be robust.

  4. Functional and genetic evidence that nucleoside transport is highly conserved in Leishmania species: Implications for pyrimidine-based chemotherapy.

    PubMed

    Alzahrani, Khalid J H; Ali, Juma A M; Eze, Anthonius A; Looi, Wan Limm; Tagoe, Daniel N A; Creek, Darren J; Barrett, Michael P; de Koning, Harry P

    2017-08-01

    Leishmania pyrimidine salvage is replete with opportunities for therapeutic intervention with enzyme inhibitors or antimetabolites. Their uptake into cells depends upon specific transporters; therefore it is essential to establish whether various Leishmania species possess similar pyrimidine transporters capable of drug uptake. Here, we report a comprehensive characterization of pyrimidine transport in L. major and L. mexicana. In both species, two transporters for uridine/adenosine were detected, one of which also transported uracil and the antimetabolites 5-fluoruracil (5-FU) and 5F,2'deoxyuridine (5F,2'dUrd), and was designated uridine-uracil transporter 1 (UUT1); the other transporter mediated uptake of adenosine, uridine, 5F,2'dUrd and thymidine and was designated Nucleoside Transporter 1 (NT1). To verify the reported L. donovani model of two NT1-like genes encoding uridine/adenosine transporters, and an NT2 gene encoding an inosine transporter, we cloned the corresponding L. major and L. mexicana genes, expressing each in T. brucei. Consistent with the L. donovani reports, the NT1-like genes of either species mediated the adenosine-sensitive uptake of [ 3 H]-uridine but not of [ 3 H]-inosine. Conversely, the NT2-like genes mediated uptake of [ 3 H]-inosine but not [ 3 H]-uridine. Among pyrimidine antimetabolites tested, 5-FU and 5F,2'dUrd were the most effective antileishmanials; resistance to both analogs was induced in L. major and L. mexicana. In each case it was found that the resistant cells had lost the transport capacity for the inducing drug. Metabolomics analysis found that the mechanism of action of 5-FU and 5F-2'dUrd was similar in both Leishmania species, with major changes in deoxynucleotide metabolism. We conclude that the pyrimidine salvage system is highly conserved in Leishmania species - essential information for the development of pyrimidine-based chemotherapy. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights

  5. Plastid Uridine Salvage Activity Is Required for Photoassimilate Allocation and Partitioning in Arabidopsis[C][W

    PubMed Central

    Chen, Mingjie; Thelen, Jay J.

    2011-01-01

    Nucleotides are synthesized from de novo and salvage pathways. To characterize the uridine salvage pathway, two genes, UKL1 and UKL2, that tentatively encode uridine kinase (UK) and uracil phosphoribosyltransferase (UPRT) bifunctional enzymes were studied in Arabidopsis thaliana. T-DNA insertions in UKL1 and UKL2 reduced transcript expression and increased plant tolerance to toxic analogs 5-fluorouridine and 5-fluorouracil. Enzyme activity assays using purified recombinant proteins indicated that UKL1 and UKL2 have UK but not UPRT activity. Subcellular localization using a C-terminal enhanced yellow fluorescent protein fusion indicated that UKL1 and UKL2 localize to plastids. The ukl2 mutant shows reduced transient leaf starch during the day. External application of orotate rescued this phenotype in ukl2, indicating pyrimidine pools are limiting for starch synthesis in ukl2. Intermediates for lignin synthesis were upregulated, and there was increased lignin and reduced cellulose content in the ukl2 mutant. Levels of ATP, ADP, ADP-glucose, UTP, UDP, and UDP-glucose were altered in a light-dependent manner. Seed composition of the ukl1 and ukl2 mutants included lower oil and higher protein compared with the wild type. Unlike single gene mutants, the ukl1 ukl2 double mutant has severe developmental defects and reduced biomass accumulation, indicating these enzymes catalyze redundant reactions. These findings point to crucial roles played by uridine salvage for photoassimilate allocation and partitioning. PMID:21828290

  6. Treatment of acute, non-traumatic pain using a combination of diclofenac-cholestyramine, uridine triphosphate, cytidine monophosphate, and hydroxycobalamin.

    PubMed

    Mibielli, Marco Antonio; Nunes, Carlos Pereira; Cohen, José Carlos; Scussel, Ari Boulanger; Higashi, Rafael; Bendavit, Gabriel Gherman; Oliveira, Lisa; Geller, Mauro

    2010-01-01

    This randomized, controlled, double-blind clinical study in parallel groups evaluated the safety and efficacy of an oral combination diclofenac-cholestyramine, nucleotides (uridine and cytidine) and vitamin B12 versus the oral combination of nucleotides and vitamin B12 in the treatment of acute, non-traumatic pain. Subjects received twice-daily, 10-day oral administration of diclofenac-cholestyramine + uridine + cytidine + vitamin B12 (Group DN, n=40) or uridine + cytidine + vitamin B12 (Group NB, n=41). The primary study endpoint was the number of subjects with VAS reduction of >30mm after 10 days of treatment. Secondary endpoints included the number of patients with improvement >5 points in the Patient Functionality Questionnaire after 10 days of treatment, and the number of subjects presenting adverse events. Treatment with the combination of diclofenac-cholestyramine, nucleotides and Vitamin B12 resulted in a higher number of subjects with VAS score reductions >30mm after 10 days of treatment (87.5% subjects) than in the control group administered nucleotides and Vitamin B12 (51.23% of subjects), (p>0.0006). A significantly higher number of subjects in the DN group (80%) had a score reduction of >5 points in the Patient Functionality Questionnaire at after 10 days of treatment compared to Group NB (29.3%), (p<0.001). The number of subjects presenting AEs did not vary significantly between treatment groups (p=0.587). The combination of diclofenac-cholestyramine with uridine, cytidine and vitamin B12 was well-tolerated over a 10-day treatment period. The combination reduced pain and improved functionality among subjects presenting acute, non-traumatic pain in the lower back, hips, and neck.

  7. Chandler wobble: two more large phase jumps revealed

    NASA Astrophysics Data System (ADS)

    Malkin, Zinovy; Miller, Natalia

    2010-12-01

    Investigations of the anomalies in the Earth rotation, in particular, the polar motion components, play an important role in our understanding of the processes that drive changes in the Earth's surface, interior, atmosphere, and ocean. This paper is primarily aimed at investigation of the Chandler wobble (CW) at the whole available 163-year interval to search for the major CW amplitude and phase variations. First, the CW signal was extracted from the IERS (International Earth Rotation and Reference Systems Service) Pole coordinates time series using two digital filters: the singular spectrum analysis and Fourier transform. The CW amplitude and phase variations were examined by means of the wavelet transform and Hilbert transform. Results of our analysis have shown that, besides the well-known CW phase jump in the 1920s, two other large phase jumps have been found in the 1850s and 2000s. As in the 1920s, these phase jumps occurred contemporarily with a sharp decrease in the CW amplitude.

  8. Carrier-mediated translocation of uridine diphosphate glucose into the lumen of endoplasmic reticulum-derived vesicles from rat liver.

    PubMed Central

    Vanstapel, F; Blanckaert, N

    1988-01-01

    Radiolabeled UDPGlc incubated with rough endoplasmic reticulum (RER)-derived microsomes from rat liver became associated with the vesicles. This microsomal uptake of nucleotide sugar was time and temperature dependent. Analysis of the molecular species containing radiolabel revealed that initial uptake represented entry of predominantly intact UDPGlc in the microsomes. Conclusive evidence for proper translocation of UDPGlc across the microsomal membrane into the intravesicular space was obtained by demonstrating that UDPGlc was transported into an osmotically sensitive compartment. Microsomal uptake of UDPGlc exhibited features characteristic of carrier-mediated transport including saturation, specificity, and countertransport. Inhibition and trans-stimulation studies showed that other uridine-containing nucleotide sugars and 5'-UMP were substrates of the postulated microsomal carrier system for UDPGlc, while cytosine- or guanosine-containing nucleotides and non-5'-uridine monophosphates were, at best, very poor substrates. UDPGlc translocation activities were lower in smooth microsomal fractions than in the RER-derived vesicles, indicating that contamination with Golgi membranes could not be responsible for microsomal transport of UDPGlc. Our findings suggest that rat liver endoplasmic reticulum possesses a carrier system mediating proper translocation of UDPGlc and 5'-uridine-substituted structural analogues across the membrane. PMID:3417868

  9. Stiffness of a wobbling mass models analysed by a smooth orthogonal decomposition of the skin movement relative to the underlying bone.

    PubMed

    Dumas, Raphaël; Jacquelin, Eric

    2017-09-06

    The so-called soft tissue artefacts and wobbling masses have both been widely studied in biomechanics, however most of the time separately, from either a kinematics or a dynamics point of view. As such, the estimation of the stiffness of the springs connecting the wobbling masses to the rigid-body model of the lower limb, based on the in vivo displacements of the skin relative to the underling bone, has not been performed yet. For this estimation, the displacements of the skin markers in the bone-embedded coordinate systems are viewed as a proxy for the wobbling mass movement. The present study applied a structural vibration analysis method called smooth orthogonal decomposition to estimate this stiffness from retrospective simultaneous measurements of skin and intra-cortical pin markers during running, walking, cutting and hopping. For the translations about the three axes of the bone-embedded coordinate systems, the estimated stiffness coefficients (i.e. between 2.3kN/m and 55.5kN/m) as well as the corresponding forces representing the connection between bone and skin (i.e. up to 400N) and corresponding frequencies (i.e. in the band 10-30Hz) were in agreement with the literature. Consistently with the STA descriptions, the estimated stiffness coefficients were found subject- and task-specific. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Synthesis, characterization and properties of uridine 5'-( -D-apio-D-furanosyl pyrophosphate).

    PubMed

    Kindel, P K; Watson, R R

    1973-06-01

    1. A method was developed for synthesizing UDP-apiose [uridine 5'-(alpha-d-apio-d-furanosyl pyrophosphate)] from UDP-glucuronic acid [uridine 5'-(alpha-d-glucopyranosyluronic acid pyrophosphate)] in 62% yield with the enzyme UDP-glucuronic acid cyclase. 2. UDP-apiose had the same mobility as uridine 5'-(alpha-d-xylopyranosyl pyrophosphate) when chromatographed on paper and when subjected to paper electrophoresis at pH5.8. When [(3)H]UDP-[U-(14)C]glucuronic acid was used as the substrate for UDP-glucuronic acid cyclase, the (3)H/(14)C ratio in the reaction product was that expected if d-apiose remained attached to the uridine. In separate experiments doubly labelled reaction product was: (a) hydrolysed at pH2 and 100 degrees C for 15min; (b) degraded at pH8.0 and 100 degrees C for 3min; (c) used as a substrate in the enzymic synthesis of [(14)C]apiin. In each type of experiment the reaction products were isolated and identified and were found to be those expected if [(3)H]UDP-[U-(14)C]apiose was the starting compound. 3. Chemical characterization established that the product containing d-[U-(14)C]apiose and phosphate formed on alkaline degradation of UDP-[U-(14)C]apiose was alpha-d-[U-(14)C]apio-d-furanosyl 1:2-cyclic phosphate. 4. Chemical characterization also established that the product containing d-[U-(14)C]apiose and phosphate formed on acid hydrolysis of alpha-d-[U-(14)C]apio-d-furanosyl 1:2-cyclic phosphate was d-[U-(14)C]apiose 2-phosphate. 5. The half-life periods for the degradation of UDP-[U-(14)C]apiose to alpha-d-[U-(14)C]apio-d-furanosyl 1:2-cyclic phosphate and UMP at pH8.0 and 80 degrees C, at pH8.0 and 25 degrees C and at pH8.0 and 4 degrees C were 31.6s, 97.2min and 16.5h respectively. The half-life period for the hydrolysis of UDP-[U-(14)C]-apiose to d-[U-(14)C]apiose and UDP at pH3.0 and 40 degrees C was 4.67min. After 20 days at pH6.2-6.6 and 4 degrees C, 17% of the starting UDP-[U-(14)C]apiose was degraded to alpha-d-[U-(14)C

  11. The Crystal Structure of Streptococcus pyogenes Uridine Phosphorylase Reveals a Distinct Subfamily of Nucleoside Phosphorylases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tran, Timothy H.; Christoffersen, S.; Allan, Paula W.

    2011-09-20

    Uridine phosphorylase (UP), a key enzyme in the pyrimidine salvage pathway, catalyzes the reversible phosphorolysis of uridine or 2'-deoxyuridine to uracil and ribose 1-phosphate or 2'-deoxyribose 1-phosphate. This enzyme belongs to the nucleoside phosphorylase I superfamily whose members show diverse specificity for nucleoside substrates. Phylogenetic analysis shows Streptococcus pyogenes uridine phosphorylase (SpUP) is found in a distinct branch of the pyrimidine subfamily of nucleoside phosphorylases. To further characterize SpUP, we determined the crystal structure in complex with the products, ribose 1-phosphate and uracil, at 1.8 {angstrom} resolution. Like Escherichia coli UP (EcUP), the biological unit of SpUP is a hexamermore » with an ?/? monomeric fold. A novel feature of the active site is the presence of His169, which structurally aligns with Arg168 of the EcUP structure. A second active site residue, Lys162, is not present in previously determined UP structures and interacts with O2 of uracil. Biochemical studies of wild-type SpUP showed that its substrate specificity is similar to that of EcUP, while EcUP is {approx}7-fold more efficient than SpUP. Biochemical studies of SpUP mutants showed that mutations of His169 reduced activity, while mutation of Lys162 abolished all activity, suggesting that the negative charge in the transition state resides mostly on uracil O2. This is in contrast to EcUP for which transition state stabilization occurs mostly at O4.« less

  12. Synthesis of methylene- and difluoromethylenephosphonate analogues of uridine-4-phosphate and 3-deazauridine-4-phosphate.

    PubMed

    Taylor, Scott D; Mirzaei, Farzad; Sharifi, Ali; Bearne, Stephen L

    2006-12-08

    Cytidine triphosphate synthetase (CTPS) catalyzes the formation of cytidine triphosphate from glutamine, uridine-5'-triphosphate (UTP), and adenosine-5'-triphosphate. Inhibitors of CTPS are of interest because of their potential as therapeutic agents. One approach to potent enzyme inhibitors is to use analogues of high energy intermediates formed during the reaction. The CTPS reaction proceeds via the high energy intermediate UTP-4-phosphate (UTP-4-P). Four novel analogues of uridine-4-phosphate (U-4-P) and 3-deazauridine-4-phosphate (3-deazaU-4-P) were synthesized in which the labile phosphate ester oxygen was replaced with a methylene and difluoromethylene group. The methylene analogue of U-4-P, compound 1, was prepared by a reaction of the sodium salt of tert-butyl diethylphosphonoacetate with protected, 4-O-activated uridine followed by acetate deprotection and decarboxylation. It was found that this compound undergoes relatively facile dephosphonylation presumably via a metaphosphate intermediate. The difluoromethylene derivative, compound 2, was prepared by electrophilic fluorination of protected 1. This compound was stable and did not undergo dephosphonylation. Synthesis of the methylene analogue of 3-deazaU-4-P, compound 3, was achieved by ribosylation of protected 4-(phosphonomethyl)-2-hydroxypyridine. Electrophilic fluorination was also employed in the preparation of protected 4-(phosphonodifluoromethyl)-2-hydroxypyridine which was used as the key building block in the synthesis of difluoro derivative 4. These compounds represent the first examples of a nucleoside in which the base has been chemically modified with a methylene or difluormethylenephosphonate group.

  13. A new description of Earth's wobble modes using Clairaut coordinates: 1. Theory

    NASA Astrophysics Data System (ADS)

    Rochester, M. G.; Crossley, D. J.; Zhang, Y. L.

    2014-09-01

    This paper presents a novel mathematical reformulation of the theory of the free wobble/nutation of an axisymmetric reference earth model in hydrostatic equilibrium, using the linear momentum description. The new features of this work consist in the use of (i) Clairaut coordinates (rather than spherical polars), (ii) standard spherical harmonics (rather than generalized spherical surface harmonics), (iii) linear operators (rather than J-square symbols) to represent the effects of rotational and ellipticity coupling between dependent variables of different harmonic degree and (iv) a set of dependent variables all of which are continuous across material boundaries. The resulting infinite system of coupled ordinary differential equations is given explicitly, for an elastic solid mantle and inner core, an inviscid outer core and no magnetic field. The formulation is done to second order in the Earth's ellipticity. To this order it is shown that for wobble modes (in which the lowest harmonic in the displacement field is degree 1 toroidal, with azimuthal order m = ±1), it is sufficient to truncate the chain of coupled displacement fields at the toroidal harmonic of degree 5 in the solid parts of the earth model. In the liquid core, however, the harmonic expansion of displacement can in principle continue to indefinitely high degree at this order of accuracy. The full equations are shown to yield correct results in three simple cases amenable to analytic solution: a general earth model in rigid rotation, the tiltover mode in a homogeneous solid earth model and the tiltover and Chandler periods for an incompressible homogeneous solid earth model. Numerical results, from programmes based on this formulation, are presented in part II of this paper.

  14. The absence of A-to-I editing in the anticodon of plant cytoplasmic tRNA (Arg) ACG demands a relaxation of the wobble decoding rules.

    PubMed

    Aldinger, Carolin A; Leisinger, Anne-Katrin; Gaston, Kirk W; Limbach, Patrick A; Igloi, Gabor L

    2012-10-01

    It is a prevalent concept that, in line with the Wobble Hypothesis, those tRNAs having an adenosine in the first position of the anticodon become modified to an inosine at this position. Sequencing the cDNA derived from the gene coding for cytoplasmic tRNA (Arg) ACG from several higher plants as well as mass spectrometric analysis of the isoacceptor has revealed that for this kingdom an unmodified A in the wobble position of the anticodon is the rule rather than the exception. In vitro translation shows that in the plant system the absence of inosine in the wobble position of tRNA (Arg) does not prevent decoding. This isoacceptor belongs to the class of tRNA that is imported from the cytoplasm into the mitochondria of higher plants. Previous studies on the mitochondrial tRNA pool have demonstrated the existence of tRNA (Arg) ICG in this organelle. In moss the mitochondrial encoded distinct tRNA (Arg) ACG isoacceptor possesses the I34 modification. The implication is that for mitochondrial protein biosynthesis A-to-I editing is necessary and occurs by a mitochondrion-specific deaminase after import of the unmodified nuclear encoded tRNA (Arg) ACG.

  15. Self-association and base pairing of guanosine, cytidine, adenosine, and uridine in dimethyl sulfoxide solution measured by 15N nuclear magnetic resonance spectroscopy.

    PubMed Central

    Dyllick-Brenzinger, C; Sullivan, G R; Pang, P P; Roberts, J D

    1980-01-01

    The self-association of guanosine, cytidine, and adenosine and base pairing between guanosine, cytidine, adenosine, and uridine in dimethyl sulfoxide have been investigated by the variation of their 15N NMR chemical shifts with concentration and temperature. Guanosine, cytidine, and adenosine all showed evidence of self-association by hydrogen bonding. In guanosine/cytidine mixtures, a hydrogen-bonded dimer is formed; however, no base pairing could be detected with adenosine/cytidine or adenosine/uridine mixtures. PMID:6932658

  16. Molecular mechanism of codon recognition by tRNA species with modified uridine in the first position of the anticodon.

    PubMed Central

    Yokoyama, S; Watanabe, T; Murao, K; Ishikura, H; Yamaizumi, Z; Nishimura, S; Miyazawa, T

    1985-01-01

    Proton NMR analyses have been made to elucidate the conformational characteristics of modified nucleotides as found in the first position of the anticodon of tRNA [derivatives of 5-methyl-2-thiouridine 5'-monophosphate (pxm5s2U) and derivatives of 5-hydroxyuridine 5'-monophosphate (pxo5U)]. In pxm5s2U, the C3'-endo form is extraordinarily more stable than the C2'-endo form for the ribose ring, because of the combined effects of the 2-thiocarbonyl group and the 5-substituent. By contrast, in pxo5U, the C2'-endo form is much more stable than the C3'-endo form, because of the interaction between the 5-substituent and the 5'-phosphate group. The enthalpy differences between the C2'-endo form and the C3'-endo form have been obtained as 1.1, -0.7, and 0.1 kcal/mol (1 cal = 4.184 J) for pxm5s2U, pxo5U, and unmodified uridine 5'-monophosphate, respectively. These findings lead to the conclusion that xm5s2U in the first position of the anticodon exclusively takes the C3'-endo form to recognize adenosine (but not uridine) as the third letter of the codon, whereas xo5U takes the C2'-endo form as well as the C3'-endo form to recognize adenosine, guanosine, and uridine as the third letter of the codon on ribosome. Accordingly, the biological significance of such modifications of uridine to xm5s2U/xo5U is in the regulation of the conformational rigidity/flexibility in the first position of the anticodon so as to guarantee the correct and efficient translation of codons in protein biosynthesis. PMID:3860833

  17. Dietary supplementation with uridine-5'-monophosphate (UMP), a membrane phosphatide precursor, increases acetylcholine level and release in striatum of aged rat.

    PubMed

    Wang, Lei; Albrecht, Meredith A; Wurtman, Richard J

    2007-02-16

    The biosynthesis of brain membrane phosphatides, e.g., phosphatidylcholine (PtdCho), may utilize three circulating compounds: choline, uridine (a precursor for UTP, CTP, and CDP-choline), and a PUFA (e.g., docosahexaenoic acid); moreover, oral administration of the uridine source uridine-5'-monophosphate (UMP) can significantly increase levels of the phosphatides throughout the rodent brain. Since PtdCho can provide choline for acetylcholine (ACh) synthesis, we determined whether UMP administration also affects ACh levels in striatum and striatal extracellular fluid, in aged and young rats. Among aged animals consuming a UMP-containing diet (2.5%, w/w) for 1 or 6 weeks, baseline ACh levels in striatal dialysates rose from 73 fmol/min to 148 or 197 fmol/min (P<0.05). Consuming a lower dose (0.5%) for 1 week produced a smaller but still significant increase (from 75 to 92 fmol/min, P<0.05), and elevated striatal ACh content (by 16%; P<0.05). Dietary UMP (0.5%, 1 week) also amplified the increase in ACh caused by giving atropine (10 microM in the aCSF); atropine alone increased ACh concentrations from 81 to 386 fmol/min in control rats and from 137 to 680 fmol/min in those consuming UMP (P<0.05). Young rats eating the UMP-containing diet exhibited similar increases in basal ECF ACh (from 105 to 118 fmol/min) and in the increase produced by atropine (from 489 to 560 fmol/min; P<0.05). These data suggest that giving a uridine source may enhance some cholinergic functions, perhaps by increasing brain phosphatide levels.

  18. Structure of a complex of uridine phosphorylase from Yersinia pseudotuberculosis with the modified bacteriostatic antibacterial drug determined by X-ray crystallography and computer analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balaev, V. V.; Lashkov, A. A., E-mail: alashkov83@gmail.com; Gabdoulkhakov, A. G.

    2015-03-15

    Pseudotuberculosis and bubonic plague are acute infectious diseases caused by the bacteria Yersinia pseudotuberculosis and Yersinia pestis. These diseases are treated, in particular, with trimethoprim and its modified analogues. However, uridine phosphorylases (pyrimidine nucleoside phosphorylases) that are present in bacterial cells neutralize the action of trimethoprim and its modified analogues on the cells. In order to reveal the character of the interaction of the drug with bacterial uridine phosphorylase, the atomic structure of the unligated molecule of uridine-specific pyrimidine nucleoside phosphorylase from Yersinia pseudotuberculosis (YptUPh) was determined by X-ray diffraction at 1.7 Å resolution with high reliability (R{sub work} =more » 16.2, R{sub free} = 19.4%; r.m.s.d. of bond lengths and bond angles are 0.006 Å and 1.005°, respectively; DPI = 0.107 Å). The atoms of the amino acid residues of the functionally important secondary-structure elements—the loop L9 and the helix H8—of the enzyme YptUPh were located. The three-dimensional structure of the complex of YptUPh with modified trimethoprim—referred to as 53I—was determined by the computer simulation. It was shown that 53I is a pseudosubstrate of uridine phosphorylases, and its pyrimidine-2,4-diamine group is located in the phosphate-binding site of the enzyme YptUPh.« less

  19. Structure of a complex of uridine phosphorylase from Yersinia pseudotuberculosis with the modified bacteriostatic antibacterial drug determined by X-ray crystallography and computer analysis

    NASA Astrophysics Data System (ADS)

    Balaev, V. V.; Lashkov, A. A.; Gabdoulkhakov, A. G.; Seregina, T. A.; Dontsova, M. V.; Mikhailov, A. M.

    2015-03-01

    Pseudotuberculosis and bubonic plague are acute infectious diseases caused by the bacteria Yersinia pseudotuberculosis and Yersinia pestis. These diseases are treated, in particular, with trimethoprim and its modified analogues. However, uridine phosphorylases (pyrimidine nucleoside phosphorylases) that are present in bacterial cells neutralize the action of trimethoprim and its modified analogues on the cells. In order to reveal the character of the interaction of the drug with bacterial uridine phosphorylase, the atomic structure of the unligated molecule of uridine-specific pyrimidine nucleoside phosphorylase from Yersinia pseudotuberculosis ( YptUPh) was determined by X-ray diffraction at 1.7 Å resolution with high reliability ( R work = 16.2, R free = 19.4%; r.m.s.d. of bond lengths and bond angles are 0.006 Å and 1.005°, respectively; DPI = 0.107 Å). The atoms of the amino acid residues of the functionally important secondary-structure elements—the loop L9 and the helix H8—of the enzyme YptUPh were located. The three-dimensional structure of the complex of YptUPh with modified trimethoprim—referred to as 53I—was determined by the computer simulation. It was shown that 53I is a pseudosubstrate of uridine phosphorylases, and its pyrimidine-2,4-diamine group is located in the phosphate-binding site of the enzyme YptUPh.

  20. Microenvironmental Effect of 2'-O-(1-Pyrenylmethyl)uridine Modified Fluorescent Oligonucleotide Probes on Sensitive and Selective Detection of Target RNA.

    PubMed

    Imincan, Gülnur; Pei, Fen; Yu, Lijia; Jin, Hongwei; Zhang, Liangren; Yang, Xiaoda; Zhang, Lihe; Tang, XinJing

    2016-04-19

    2'-O-(1-Pyrenylmethyl)uridine modified oligoribonucleotides provide highly sensitive pyrene fluorescent probes for detecting specific nucleotide mutation of RNA targets. To develop more stable and cost-effective oligonucleotide probes, we investigated the local microenvironmental effects of nearby nucleobases on pyrene fluorescence in duplexes of RNAs and 2'-O-(1-pyrenylmethyl)uridine modified oligonucleotides. By incorporation of deoxyribonucleotides, ribonucleotides, 2'-MeO-nucleotides and 2'-F-nucleotides at both sides of 2'-O-(1-pyrenylmethyl)uridine (U(p)) in oligodeoxynucleotide probes, we synthesized a series of pyrene modified oligonucleotide probes. Their pyrene fluorescence emission spectra indicated that only two proximal nucleotides have a substantial effect on the pyrene fluorescence properties of these oligonucleotide probes hybridized with target RNA with an order of fluorescence sensitivity of 2'-F-nucleotides > 2'-MeO-nucleotides > ribonucleotides ≫ deoxyribonucleotides. While based on circular dichroism spectra, overall helix conformations (either A- or B-form) of the duplexes have marginal effects on the sensitivity of the probes. Instead, the local substitution reflected the propensity of the nucleotide sugar ring to adopt North type conformation and, accordingly, shifted their helix geometry toward a more A-type like conformation in local microenvironments. Thus, higher enhancement of pyrene fluorescence emission favored local A-type helix structures and more polar and hydrophobic environments (F > MeO > OH at 2' substitution) of duplex minor grooves of probes with the target RNA. Further dynamic simulation revealed that local microenvironmental effect of 2'-F-nucleotides or ribonucleotides was enough for pyrene moiety to move out of nucleobases to the minor groove of duplexes; in addition, 2'-F-nucleotide had less effect on π-stack of pyrene-modified uridine with upstream and downstream nucleobases. The present oligonucleotide probes

  1. Feature extraction of micro-motion frequency and the maximum wobble angle in a small range of missile warhead based on micro-Doppler effect

    NASA Astrophysics Data System (ADS)

    Li, M.; Jiang, Y. S.

    2014-11-01

    Micro-Doppler effect is induced by the micro-motion dynamics of the radar target itself or any structure on the target. In this paper, a simplified cone-shaped model for ballistic missile warhead with micro-nutation is established, followed by the theoretical formula of micro-nutation is derived. It is confirmed that the theoretical results are identical to simulation results by using short-time Fourier transform. Then we propose a new method for nutation period extraction via signature maximum energy fitting based on empirical mode decomposition and short-time Fourier transform. The maximum wobble angle is also extracted by distance approximate approach in a small range of wobble angle, which is combined with the maximum likelihood estimation. By the simulation studies, it is shown that these two feature extraction methods are both valid even with low signal-to-noise ratio.

  2. Synthesis, characterization and properties of uridine 5′-(α-d-apio-d-furanosyl pyrophosphate)

    PubMed Central

    Kindel, Paul K.; Watson, Ronald R.

    1973-01-01

    1. A method was developed for synthesizing UDP-apiose [uridine 5′-(α-d-apio-d-furanosyl pyrophosphate)] from UDP-glucuronic acid [uridine 5′-(α-d-glucopyranosyluronic acid pyrophosphate)] in 62% yield with the enzyme UDP-glucuronic acid cyclase. 2. UDP-apiose had the same mobility as uridine 5′-(α-d-xylopyranosyl pyrophosphate) when chromatographed on paper and when subjected to paper electrophoresis at pH5.8. When [3H]UDP-[U-14C]glucuronic acid was used as the substrate for UDP-glucuronic acid cyclase, the 3H/14C ratio in the reaction product was that expected if d-apiose remained attached to the uridine. In separate experiments doubly labelled reaction product was: (a) hydrolysed at pH2 and 100°C for 15min; (b) degraded at pH8.0 and 100°C for 3min; (c) used as a substrate in the enzymic synthesis of [14C]apiin. In each type of experiment the reaction products were isolated and identified and were found to be those expected if [3H]UDP-[U-14C]apiose was the starting compound. 3. Chemical characterization established that the product containing d-[U-14C]apiose and phosphate formed on alkaline degradation of UDP-[U-14C]apiose was α-d-[U-14C]apio-d-furanosyl 1:2-cyclic phosphate. 4. Chemical characterization also established that the product containing d-[U-14C]apiose and phosphate formed on acid hydrolysis of α-d-[U-14C]apio-d-furanosyl 1:2-cyclic phosphate was d-[U-14C]apiose 2-phosphate. 5. The half-life periods for the degradation of UDP-[U-14C]apiose to α-d-[U-14C]apio-d-furanosyl 1:2-cyclic phosphate and UMP at pH8.0 and 80°C, at pH8.0 and 25°C and at pH8.0 and 4°C were 31.6s, 97.2min and 16.5h respectively. The half-life period for the hydrolysis of UDP-[U-14C]-apiose to d-[U-14C]apiose and UDP at pH3.0 and 40°C was 4.67min. After 20 days at pH6.2–6.6 and 4°C, 17% of the starting UDP-[U-14C]apiose was degraded to α-d-[U-14C]apio-d-furanosyl 1:2-cyclic phosphate and UMP and 23% was hydrolysed to d-[U-14C]apiose and UDP. After 120 days at p

  3. Black hole spin from wobbling and rotation of the M87 jet and a sign of a magnetically arrested disc

    NASA Astrophysics Data System (ADS)

    Sob'yanin, Denis Nikolaevich

    2018-06-01

    New long-term Very Long Baseline Array observations of the well-known jet in the M87 radio galaxy at 43 GHz show that the jet experiences a sideways shift with an approximately 8-10 yr quasi-periodicity. Such jet wobbling can be indicative of a relativistic Lense-Thirring precession resulting from a tilted accretion disc. The wobbling period together with up-to-date kinematic data on jet rotation opens up the possibility for estimating angular momentum of the central supermassive black hole. In the case of a test-particle precession, the specific angular momentum is J/Mc = (2.7 ± 1.5) × 1014 cm, implying moderate dimensionless spin parameters a = 0.5 ± 0.3 and 0.31 ± 0.17 for controversial gas-dynamic and stellar-dynamic black hole masses. However, in the case of a solid-body-like precession, the spin parameter is much smaller for both masses, 0.15 ± 0.05. Rejecting this value on the basis of other independent spin estimations requires the existence of a magnetically arrested disc in M87.

  4. Structure-activity relationship of uridine-based nucleoside phosphoramidate prodrugs for inhibition of dengue virus RNA-dependent RNA polymerase.

    PubMed

    Wang, Gang; Lim, Siew Pheng; Chen, Yen-Liang; Hunziker, Jürg; Rao, Ranga; Gu, Feng; Seh, Cheah Chen; Ghafar, Nahdiyah Abdul; Xu, Haoying; Chan, Katherine; Lin, Xiaodong; Saunders, Oliver L; Fenaux, Martijn; Zhong, Weidong; Shi, Pei-Yong; Yokokawa, Fumiaki

    2018-05-03

    To identify a potent and selective nucleoside inhibitor of dengue virus RNA-dependent RNA polymerase, a series of 2'- and/or 4'-ribose sugar modified uridine nucleoside phosphoramidate prodrugs and their corresponding triphosphates were synthesized and evaluated. Replacement of 2'-OH with 2'-F led to be a poor substrate for both dengue virus and human mitochondrial RNA polymerases. Instead of 2'-fluorination, the introduction of fluorine at the ribose 4'-position was found not to affect the inhibition of the dengue virus polymerase with a reduction in uptake by mitochondrial RNA polymerase. 2'-C-ethynyl-4'-F-uridine phosphoramidate prodrug displayed potent anti-dengue virus activity in the primary human peripheral blood mononuclear cell-based assay with no significant cytotoxicity in human hepatocellular liver carcinoma cell lines and no mitochondrial toxicity in the cell-based assay using human prostate cancer cell lines. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Dietary uridine enhances the improvement in learning and memory produced by administering DHA to gerbils.

    PubMed

    Holguin, Sarah; Martinez, Joseph; Chow, Camille; Wurtman, Richard

    2008-11-01

    This study examined the effects on cognitive behaviors of giving normal adult gerbils three compounds, normally in the circulation, which interact to increase brain phosphatides, synaptic proteins, dendritic spines, and neurotransmitter release. Animals received supplemental uridine (as its monophosphate, UMP; 0.5%) and choline (0.1%) via the diet, and docosahexaenoic acid (DHA; 300 mg/kg/day) by gavage, for 4 wk, and then throughout the subsequent period of behavioral training and testing. As shown previously, giving all three compounds caused highly significant (P<0.001) increases in total brain phospholipids and in each major phosphatide; giving DHA or UMP (plus choline) produced smaller increases in some of the phosphatides. DHA plus choline improved performance on the four-arm radial maze, T-maze, and Y-maze tests; coadministering UMP further enhanced these increases. (Uridine probably acts by generating both CTP, which can be limiting in phosphatide synthesis, and UTP, which activates P2Y receptors coupled to neurite outgrowth and protein synthesis. All three compounds also act by enhancing the substrate-saturation of phosphatide-synthesizing enzymes.) These findings demonstrate that a treatment that increases synaptic membrane content can enhance cognitive functions in normal animals.

  6. Evaluation of uridine 5'-eicosylphosphate as a stimulant of cyclic AMP-dependent cellular function.

    PubMed

    Yutani, Masahiro; Ogita, Akira; Fujita, Ken-Ichi; Usuki, Yoshinosuke; Tanaka, Toshio

    2011-03-01

    Sporulation of the yeast Saccharomyces cerevisiae is negatively regulated by cyclic AMP (cAMP). This microbial cell differentiation process was applied for the screening of a substance that can elevate the intracellular cAMP level. Among nucleoside 5'-alkylphosphates, uridine 5'-eicosylphosphate (UMPC20) selectively and predominantly inhibited ascospore formation of the yeast cells. We suppose the inhibitory effect of UMPC20 could indeed reflect the elevation of the cellular cAMP level.

  7. “Escargot Effect” and the Chandler Wobble Excitation

    NASA Astrophysics Data System (ADS)

    Zotov, Leonid; Bizouard, Christian

    2018-01-01

    We study the Chandler wobble (CW) of the pole from 1846 to 2017 extracted by the Panteleev filtering. The CW has period of 433 days, average amplitude of 0.13 milliarcseconds (mas) which is changing, and phase jump by ϕ in 1930-th. The CW amplitude strongly (almost to zero) decreases in 1930-th and 2010-th with the phase jump in 1930th. The envelope model contains 83- and 42-years quasi-periodicities. We think the first one can be represented by the 166-years changes of the envelope, crossing zero in 1930th. We reconstruct Chandler input excitation based on the Euler-Liouville equation. Its amplitude has ∼ 20-years variations. We explain this based on simple model and prove, that they appear in consequence of 42-years modulation of CW. The excitation amplifies the amplitude of CW for ∼ 20 years then damps it for another ∼ 20 years. The analysis of the modulated CW signal in a sliding window demonstrates the specific effect, we called the “escargot effect”, when instantaneous “virtual” retrograde component appears in the purely prograde (at long-time interval) signal. Chandler excitation envelope shape is similar to this instantaneous retrograde component, which reflects the changes of ellipticity of the approximation ellipse.

  8. Wobbled electronic properties of lithium clusters: Deterministic approach through first principles

    NASA Astrophysics Data System (ADS)

    Kushwaha, Anoop Kumar; Nayak, Saroj Kumar

    2018-03-01

    The innate tendency to form dendritic growth promoted through cluster formation leading to the failure of a Li-ion battery system have drawn significant attention of the researchers towards the effective destabilization of the cluster growth through selective implementation of electrolytic media such as acetonitrile (MeCN). In the present work, using first principles density functional theory and continuum dielectric model, we have investigated the origin of oscillatory nature of binding energy per atom of Lin (n ≤ 8) under the influence of MeCN. In the gas phase, we found that static mean polarizability is strongly correlated with binding energy and shows oscillatory nature with cluster size due to the open shell of Lin cluster. However, in acetonitrile medium, the binding energy has been correlated with electrostatic Lin -MeCN interaction and it has been found that both of them possess wobbled behavior characterized by the cluster size.

  9. Giving uridine and/or docosahexaenoic acid orally to rat dams during gestation and nursing increases synaptic elements in brains of weanling pups.

    PubMed

    Cansev, Mehmet; Marzloff, George; Sakamoto, Toshimasa; Ulus, Ismail H; Wurtman, Richard J

    2009-01-01

    Developing neurons synthesize substantial quantities of membrane phospholipids in producing new synapses. We investigated the effects of maternal uridine (as uridine-5'-monophosphate) and docosahexaenoic acid supplementation on pups' brain phospholipids, synaptic proteins and dendritic spine densities. Dams consumed neither, 1 or both compounds for 10 days before parturition and 20 days while nursing. By day 21, brains of weanlings receiving both exhibited significant increases in membrane phosphatides, various pre- and postsynaptic proteins (synapsin-1, mGluR1, PSD-95), and in hippocampal dendritic spine densities. Administering these phosphatide precursors to lactating mothers or infants could be useful for treating developmental disorders characterized by deficient synapses. 2009 S. Karger AG, Basel.

  10. Biological Evaluation of Uridine Derivatives of 2-Deoxy Sugars as Potential Antiviral Compounds against Influenza A Virus

    PubMed Central

    Krol, Ewelina; Wandzik, Ilona; Szewczyk, Boguslaw

    2017-01-01

    Influenza virus infection is a major cause of morbidity and mortality worldwide. Due to the limited ability of currently available treatments, there is an urgent need for new anti-influenza drugs with broad spectrum protection. We have previously shown that two 2-deoxy sugar derivatives of uridine (designated IW3 and IW7) targeting the glycan processing steps during maturation of viral glycoproteins show good anti-influenza virus activity and may be a promising alternative approach for the development of new anti-influenza therapy. In this study, a number of IW3 and IW7 analogues with different structural modifications in 2-deoxy sugar or uridine parts were synthesized and evaluated for their ability to inhibit influenza A virus infection in vitro. Using the cytopathic effect (CPE) inhibition assay and viral plaque reduction assay in vitro, we showed that compounds 2, 3, and 4 exerted the most inhibitory effect on influenza virus A/ostrich/Denmark/725/96 (H5N2) infection in Madin-Darby canine kidney (MDCK) cells, with 50% inhibitory concentrations (IC50) for virus growth ranging from 82 to 100 (μM) without significant toxicity for the cells. The most active compound (2) showed activity of 82 μM with a selectivity index value of 5.27 against type A (H5N2) virus. Additionally, compound 2 reduced the formation of HA glycoprotein in a dose-dependent manner. Moreover, an analysis of physicochemical properties of studied compounds demonstrated a significant linear correlation between lipophilicity and antiviral activity. Therefore, inhibition of influenza A virus infection by conjugates of uridine and 2-deoxy sugars is a new promising approach for the development of new derivatives with anti-influenza activities. PMID:28777309

  11. Structural basis for the mechanism of inhibition of uridine phosphorylase from Salmonella typhimurium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lashkov, A. A.; Zhukhlistova, N. E.; Sotnichenko, S. E.

    2010-01-15

    The three-dimensional structures of three complexes of Salmonella typhimurium uridine phosphorylase with the inhibitor 2,2'-anhydrouridine, the substrate PO{sub 4}, and with both the inhibitor 2,2'-anhydrouridine and the substrate PO{sub 4} (a binary complex) were studied in detail by X-ray diffraction. The structures of the complexes were refined at 2.38, 1.5, and 1.75 A resolution, respectively. Changes in the three-dimensional structure of the subunits in different crystal structures are considered depending on the presence or absence of the inhibitor molecule and (or) the phosphate ion in the active site of the enzyme. The presence of the phosphate ion in the phosphate-bindingmore » site was found to substantially change the orientations of the side chains of the amino-acid residues Arg30, Arg91, and Arg48 coordinated to this ion. A comparison showed that the highly flexible loop L9 is unstable. The atomic coordinates of the refined structures of the complexes and the corresponding structure factors were deposited in the Protein Data Bank (their PDB ID codes are 3DD0 and 3C74). The experimental data on the spatial reorganization of the active site caused by changes in its functional state from the unligated to the completely inhibited state suggest the structural basis for the mechanism of inhibition of Salmonella typhimurium uridine phosphorylase.« less

  12. Modified nucleoside dependent Watson-Crick and wobble codon binding by tRNALysUUU species.

    PubMed

    Yarian, C; Marszalek, M; Sochacka, E; Malkiewicz, A; Guenther, R; Miskiewicz, A; Agris, P F

    2000-11-07

    Nucleoside modifications are important to the structure of all tRNAs and are critical to the function of some tRNA species. The transcript of human tRNA(Lys3)(UUU) with a UUU anticodon, and the corresponding anticodon stem and loop domain (ASL(Lys3)(UUU)), are unable to bind to poly-A programmed ribosomes. To determine if specific anticodon domain modified nucleosides of tRNA(Lys) species would restore ribosomal binding and also affect thermal stability, we chemically synthesized ASL(Lys) heptadecamers and site-specifically incorporated the anticodon domain modified nucleosides pseudouridine (Psi(39)), 5-methylaminomethyluridine (mnm(5)U(34)) and N6-threonylcarbamoyl-adenosine (t(6)A(37)). Incorporation of t(6)A(37) and mnm(5)U(34) contributed structure to the anticodon loop, apparent by increases in DeltaS, and significantly enhanced the ability of ASL(Lys3)(UUU) to bind poly-A programmed ribosomes. Neither ASL(Lys3)(UUU)-t(6)A(37) nor ASL(Lys3)(UUU)-mnm(5)U(34) bound AAG programmed ribosomes. Only the presence of both t(6)A(37) and mnm(5)U(34) enabled ASL(Lys3)(UUU) to bind AAG programmed ribosomes, as well as increased its affinity for poly-A programmed ribosomes to the level of native Escherichia coli tRNA(Lys). The completely unmodified anticodon stem and loop of human tRNA(Lys1,2)(CUU) with a wobble position-34 C bound AAG, but did not wobble to AAA, even when the ASL was modified with t(6)A(37). The data suggest that tRNA(Lys)(UUU) species require anticodon domain modifications in the loop to impart an ordered structure to the anticodon for ribosomal binding to AAA and require a combination of modified nucleosides to bind AAG.

  13. Lack of incorporation of tritiated uridine by nuclei of mature sieve elements in Metasequoia glyptostroboides and Sequoiadendron giganteum.

    PubMed

    Hébant, C

    1975-01-01

    The majority of nuclei which persist in "mature" sieve elements of Metasequoia glyptostroboides Hu and Chen and Sequoiadendron giganteum Buchholz fail to incorporate tritiated uridine (10 μCi/ml; 7 hours incubation of stem fragments). This is interpreted as further evidence for the degenerated condition of these nuclei.

  14. Phosphorylation of Elp1 by Hrr25 Is Required for Elongator-Dependent tRNA Modification in Yeast

    PubMed Central

    Abdel-Fattah, Wael; Jablonowski, Daniel; Di Santo, Rachael; Thüring, Kathrin L.; Scheidt, Viktor; Hammermeister, Alexander; ten Have, Sara; Helm, Mark; Schaffrath, Raffael; Stark, Michael J. R.

    2015-01-01

    Elongator is a conserved protein complex comprising six different polypeptides that has been ascribed a wide range of functions, but which is now known to be required for modification of uridine residues in the wobble position of a subset of tRNAs in yeast, plants, worms and mammals. In previous work, we showed that Elongator's largest subunit (Elp1; also known as Iki3) was phosphorylated and implicated the yeast casein kinase I Hrr25 in Elongator function. Here we report identification of nine in vivo phosphorylation sites within Elp1 and show that four of these, clustered close to the Elp1 C-terminus and adjacent to a region that binds tRNA, are important for Elongator's tRNA modification function. Hrr25 protein kinase directly modifies Elp1 on two sites (Ser-1198 and Ser-1202) and through analyzing non-phosphorylatable (alanine) and acidic, phosphomimic substitutions at Ser-1198, Ser-1202 and Ser-1209, we provide evidence that phosphorylation plays a positive role in the tRNA modification function of Elongator and may regulate the interaction of Elongator both with its accessory protein Kti12 and with Hrr25 kinase. PMID:25569479

  15. In silico analysis of the three-dimensional structures of the homodimer of uridine phosphorylase from Yersinia Pseudotuberculosis in the ligand-free state and in a complex with 5-fluorouracil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lashkov, A. A., E-mail: alashkov83@gmail.com; Sotnichenko, S. E.; Mikhailov, A. M.

    2013-03-15

    Pseudotuberculosis is an acute infectious disease characterized by a lesion of the gastrointestinal tract. A positive therapeutic effect can be achieved by selectively suppressing the activity of uridine phosphorylase from the causative agent of the disease Yersinia pseudotuberculosis. The synergistic effect of a combination of the chemotherapeutic agent 5-fluorouracil and antimicrobial drugs, which block the synthesis of pyrimidine bases, on the cells of pathogenic protozoa and bacteria is described in the literature. The three-dimensional structures of uridine phosphorylase from Yersinia pseudotuberculosis (YptUPh) both in the ligand-free state and in complexes with pharmacological agents are unknown, which hinders the search formore » and design of selective inhibitors of YptUPh. The three-dimensional structure of the ligand-free homodimer of YptUPh was determined by homology-based molecular modeling. The three-dimensional structure of the subunit of the YptUPh molecule belongs to {alpha}/{beta} proteins, and its topology is a three-layer {alpha}/{beta}/{alpha} sandwich. The subunit monomer of the YptUPh molecule consists of 38% helices and 24% {beta} strands. A model of the homodimer structure of YptUPh in a complex with 5-FU was obtained by the molecular docking. The position of 5-FU in the active site of the molecule is very consistent with the known data on the X-ray diffraction structures of other bacterial uridine phosphorylases (the complex of uridine phosphorylase from Salmonella typhimurium (StUPh) with 5-FU, ID PDB: 4E1V and the complex of uridine phosphorylase from Escherichia coli (EcUPh) with 5-FU and ribose 1-phosphate, ID PDB: 1RXC).« less

  16. In silico analysis of the three-dimensional structures of the homodimer of uridine phosphorylase from Yersinia Pseudotuberculosis in the ligand-free state and in a complex with 5-fluorouracil

    NASA Astrophysics Data System (ADS)

    Lashkov, A. A.; Sotnichenko, S. E.; Mikhailov, A. M.

    2013-03-01

    Pseudotuberculosis is an acute infectious disease characterized by a lesion of the gastrointestinal tract. A positive therapeutic effect can be achieved by selectively suppressing the activity of uridine phosphorylase from the causative agent of the disease Yersinia pseudotuberculosis. The synergistic effect of a combination of the chemotherapeutic agent 5-fluorouracil and antimicrobial drugs, which block the synthesis of pyrimidine bases, on the cells of pathogenic protozoa and bacteria is described in the literature. The three-dimensional structures of uridine phosphorylase from Yersinia pseudotuberculosis ( YptUPh) both in the ligand-free state and in complexes with pharmacological agents are unknown, which hinders the search for and design of selective inhibitors of YptUPh. The three-dimensional structure of the ligand-free homodimer of YptUPh was determined by homology-based molecular modeling. The three-dimensional structure of the subunit of the YptUPh molecule belongs to α/β proteins, and its topology is a three-layer α/β/α sandwich. The subunit monomer of the YptUPh molecule consists of 38% helices and 24% β strands. A model of the homodimer structure of YptUPh in a complex with 5-FU was obtained by the molecular docking. The position of 5-FU in the active site of the molecule is very consistent with the known data on the X-ray diffraction structures of other bacterial uridine phosphorylases (the complex of uridine phosphorylase from Salmonella typhimurium ( StUPh) with 5-FU, ID PDB: 4E1V and the complex of uridine phosphorylase from Escherichia coli ( EcUPh) with 5-FU and ribose 1-phosphate, ID PDB: 1RXC).

  17. Predicting the NMR spectra of nucleotides by DFT calculations: cyclic uridine monophosphate.

    PubMed

    Bagno, Alessandro; Rastrelli, Federico; Saielli, Giacomo

    2008-06-01

    We present an experimental and quantum chemical NMR study of the mononucleotide cyclic uridine monophosphate in water. Spectral parameters ((1)H and (13)C chemical shifts and (1)H--(1)H, (13)C--(1)H, (31)P--(13)C and (31)P--(1)H spin-spin coupling constants) have been carefully obtained experimentally and calculated using DFT methods including the solvent effect and the conformational flexibility of the solute. This study confirms that the (1)H and (13)C spectra of polar, flexible molecules in aqueous solution can be predicted with a high level of accuracy, comparable to that obtained for less complex systems. Copyright (c) 2008 John Wiley & Sons, Ltd

  18. Statin Lactonization by Uridine 5'-Diphospho-glucuronosyltransferases (UGTs).

    PubMed

    Schirris, Tom J J; Ritschel, Tina; Bilos, Albert; Smeitink, Jan A M; Russel, Frans G M

    2015-11-02

    Statins are cholesterol-lowering drugs that have proven to be effective in lowering the risk of major cardiovascular events. Although well tolerated, statin-induced myopathies are the most common side effects. Compared to their pharmacologically active acid form, statin lactones are more potent inducers of toxicity. They can be formed by glucuronidation mediated by uridine 5'-diphospho-glucuronosyltransferases (UGTs), but a systematic characterization of subtype specificity and kinetics of lactonization is lacking. Here, we demonstrate for six clinically relevant statins that only UGT1A1, 1A3, and 2B7 contribute significantly to their lactonization. UGT1A3 appeared to have the highest lactonization capacity with marked differences in statin conversion rates: pitavastatin ≫ atorvastatin > cerivastatin > lovastatin > rosuvastatin (simvastatin not converted). Using in silico modeling we could identify a probable statin interaction region in the UGT binding pocket. Polymorphisms in these regions of UGT1A1, 1A3, and 2B7 may be a contributing factor in statin-induced myopathies, which could be used in personalization of statin therapy with improved safety.

  19. Stability of the wobbling motion in the triaxially deformed odd-A nucleus

    NASA Astrophysics Data System (ADS)

    Tanabe, Kosai; Sugawara-Tanabe, Kazuko

    2017-12-01

    In order to analyze the content of the exact solutions for particle-rotor models with both the rigid and the hydrodynamical moments of inertia (MoI), as a theoretical probe we apply the Holstein-Primakoff (HP) boson expansion method to the total angular momentum I and the single-particle angular momentum j. We study the competition between Coriolis force and the single-particle potential by employing the different choices of the diagonal HP boson representations for the components of I and j along a common coordinate axis, and along perpendicular axes. We do not find any wobbling level sequence associated with the rotation around the principal axis with the medium MoI. The staggering in the alignments of I about the axis with the medium MoI is found in the limited range of I, while the vector R(=I-j) is confined about the axis with the largest MoI.

  20. SU-E-T-594: Out-Of-Field Neutron and Gamma Dose Estimated Using TLD-600/700 Pairs in the Wobbling Proton Therapy System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Y; Lin, Y; Medical Physics Research Center, Institute for Radiological Research, Chang Gung University / Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan

    Purpose: Secondary fast neutrons and gamma rays are mainly produced due to the interaction of the primary proton beam with the beam delivery nozzle. These secondary radiation dose to patients and radiation workers are unwanted. The purpose of this study is to estimate the neutron and gamma dose equivalent out of the treatment volume during the wobbling proton therapy system. Methods: Two types of thermoluminescent (TL) dosimeters, TLD-600 ({sup 6}LiF: Mg, Ti) and TLD-700 ({sup 7}LiF: Mg, Ti) were used in this study. They were calibrated in the standard neutron and gamma sources at National Standards Laboratory. Annealing procedure ismore » 400°C for 1 hour, 100°C for 2 hours and spontaneously cooling down to the room temperature in a programmable oven. Two-peak method (a kind of glow curve analysis technique) was used to evaluate the TL response corresponding to the neutron and gamma dose. The TLD pairs were placed outside the treatment field at the neutron-gamma mixed field with 190-MeV proton beam produced by the wobbling system through the polyethylene plate phantom. The results of TLD measurement were compared to the Monte Carlo simulation. Results: The initial experiment results of calculated dose equivalents are 0.63, 0.38, 0.21 and 0.13 mSv per Gy outside the field at the distance of 50, 100, 150 and 200 cm. Conclusion: The TLD-600 and TLD-700 pairs are convenient to estimate neutron and gamma dosimetry during proton therapy. However, an accurate and suitable glow curve analysis technique is necessary. During the wobbling system proton therapy, our results showed that the neutron and gamma doses outside the treatment field are noticeable. This study was supported by the grants from the Chang Gung Memorial Hospital (CMRPD1C0682)« less

  1. Structure of bovine pancreatic ribonuclease complexed with uridine 5'-monophosphate at 1.60 A resolution.

    PubMed

    Larson, Steven B; Day, John S; Nguyen, Chieugiang; Cudney, Robert; McPherson, Alexander

    2010-02-01

    Bovine pancreatic ribonuclease A (RNase A) was crystallized from a mixture of small molecules containing basic fuchsin, tobramycin and uridine 5'-monophosphate (U5P). Solution of the crystal structure revealed that the enzyme was selectively bound to U5P, with the pyrimidine ring of U5P residing in the pyrimidine-binding site at Thr45. The structure was refined to an R factor of 0.197 and an R(free) of 0.253.

  2. Identification of endoplasmic reticulum proteins involved in glycan assembly: synthesis and characterization of P3-(4-azidoanilido)uridine 5'-triphosphate, a membrane-topological photoaffinity probe for uridine diphosphate-sugar binding proteins.

    PubMed Central

    Rancour, D M; Menon, A K

    1998-01-01

    Much of the enzymic machinery required for the assembly of cell surface carbohydrates is located in the endoplasmic reticulum (ER) of eukaryotic cells. Structural information on these proteins is limited and the identity of the active polypeptide(s) is generally unknown. This paper describes the synthesis and characteristics of a photoaffinity reagent that can be used to identify and analyse members of the ER glycan assembly apparatus, specifically those glycosyltransferases, nucleotide phosphatases and nucleotide-sugar transporters that recognize uridine nucleotides or UDP-sugars. The photoaffinity reagent, P3-(4-azidoanilido)uridine 5'-triphosphate (AAUTP), was synthesized easily from commercially available precursors. AAUTP inhibited the activity of ER glycosyltransferases that utilize UDP-GlcNAc and UDP-Glc, indicating that it is recognized by UDP-sugar-binding proteins. In preliminary tests AAUTP[alpha-32P] labelled bovine milk galactosyltransferase, a model UDP-sugar-utilizing enzyme, in a UV-light-dependent, competitive and saturable manner. When incubated with rat liver ER vesicles, AAUTP[alpha-32P] labelled a discrete subset of ER proteins; labelling was light-dependent and metal ion-specific. Photolabelling of intact ER vesicles with AAUTP[alpha-32P] caused selective incorporation of radioactivity into proteins with cytoplasmically disposed binding sites; UDP-Glc:glycoprotein glucosyltransferase, a lumenal protein, was labelled only when the vesicle membrane was disrupted. These data indicate that AAUTP is a membrane topological probe of catalytic sites in target proteins. Strategies for using AAUTP to identify and study novel ER proteins involved in glycan assembly are discussed. PMID:9677326

  3. Novel poly-uridine insertion in the 3'UTR and E2 amino acid substitutions in a low virulent classical swine fever virus.

    PubMed

    Coronado, Liani; Liniger, Matthias; Muñoz-González, Sara; Postel, Alexander; Pérez, Lester Josue; Pérez-Simó, Marta; Perera, Carmen Laura; Frías-Lepoureau, Maria Teresa; Rosell, Rosa; Grundhoff, Adam; Indenbirken, Daniela; Alawi, Malik; Fischer, Nicole; Becher, Paul; Ruggli, Nicolas; Ganges, Llilianne

    2017-03-01

    In this study, we compared the virulence in weaner pigs of the Pinar del Rio isolate and the virulent Margarita strain. The latter caused the Cuban classical swine fever (CSF) outbreak of 1993. Our results showed that the Pinar del Rio virus isolated during an endemic phase is clearly of low virulence. We analysed the complete nucleotide sequence of the Pinar del Rio virus isolated after persistence in newborn piglets, as well as the genome sequence of the inoculum. The consensus genome sequence of the Pinar del Rio virus remained completely unchanged after 28days of persistent infection in swine. More importantly, a unique poly-uridine tract was discovered in the 3'UTR of the Pinar del Rio virus, which was not found in the Margarita virus or any other known CSFV sequences. Based on RNA secondary structure prediction, the poly-uridine tract results in a long single-stranded intervening sequence (SS) between the stem-loops I and II of the 3'UTR, without major changes in the stem- loop structures when compared to the Margarita virus. The possible implications of this novel insertion on persistence and attenuation remain to be investigated. In addition, comparison of the amino acid sequence of the viral proteins E rns , E1, E2 and p7 of the Margarita and Pinar del Rio viruses showed that all non-conservative amino acid substitutions acquired by the Pinar del Rio isolate clustered in E2, with two of them being located within the B/C domain. Immunisation and cross-neutralisation experiments in pigs and rabbits suggest differences between these two viruses, which may be attributable to the amino acid differences observed in E2. Altogether, these data provide fresh insights into viral molecular features which might be associated with the attenuation and adaptation of CSFV for persistence in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Accuracy of Td-DFT in the Ultraviolet and Circular Dichroism Spectra of Deoxyguanosine and Uridine.

    PubMed

    Miyahara, Tomoo; Nakatsuji, Hiroshi

    2018-01-11

    Accuracy of the time-dependent density functional theory (Td-DFT) was examined for the ultraviolet (UV) and circular dichroism (CD) spectra of deoxyguanosine (dG) and uridine, using 11 different DFT functionals and two different basis sets. The Td-DFT results of the UV and CD spectra were strongly dependent on the functionals used. The basis-set dependence was observed only for the CD spectral calculations. For the UV spectra, the B3LYP and PBE0 functionals gave relatively good results. For the CD spectra, the B3LYP and PBE0 with 6-311G(d,p) basis gave relatively permissible result only for dG. The results of other functionals were difficult to be used for the studies of the UV and CD spectra, though the symmetry adapted cluster-configuration interaction (SAC-CI) method reproduced well the experimental spectra of these molecules. To obtain valuable information from the theoretical calculations of the UV and CD spectra, the theoretical tool must be able to reproduce correctly both of the intensities and peak positions of the UV and CD spectra. Then, we can analyze the reasons of the changes of the intensity and/or the peak position to clarify the chemistry involved. It is difficult to recommend Td-DFT as such tools of science, at least from the examinations using dG and uridine.

  5. A new and efficient approach for construction of uridine/uracil auxotrophic mutants in the filamentous fungus Aspergillus oryzae using Agrobacterium tumefaciens-mediated transformation.

    PubMed

    Nguyen, Khuyen Thi; Ho, Quynh Ngoc; Do, Loc Thi Binh Xuan; Mai, Linh Thi Dam; Pham, Duc-Ngoc; Tran, Huyen Thi Thanh; Le, Diep Hong; Nguyen, Huy Quang; Tran, Van-Tuan

    2017-06-01

    Aspergillus oryzae is a filamentous fungus widely used in food industry and as a microbial cell factory for recombinant protein production. Due to the inherent resistance of A. oryzae to common antifungal compounds, genetic transformation of this mold usually requires auxotrophic mutants. In this study, we show that Agrobacterium tumefaciens-mediated transformation (ATMT) method is very efficient for deletion of the pyrG gene in different Aspergillus oryzae wild-type strains to generate uridine/uracil auxotrophic mutants. Our data indicated that all the obtained uridine/uracil auxotrophic transformants, which are 5- fluoroorotic acid (5-FOA) resistant, exist as the pyrG deletion mutants. Using these auxotrophic mutants and the pyrG selectable marker for genetic transformation via A. tumefaciens, we could get about 1060 transformants per 10 6 fungal spores. In addition, these A. oryzae mutants were also used successfully for expression of the DsRed fluorescent reporter gene under control of the A. oryzae amyB promoter by the ATMT method, which resulted in obvious red transformants on agar plates. Our work provides a new and effective approach for constructing the uridine/uracil auxotrophic mutants in the importantly industrial fungus A. oryzae. This strategy appears to be applicable to other filamentous fungi to develop similar genetic transformation systems based on auxotrophic/nutritional markers for food-grade recombinant applications.

  6. A novel procedure for purification of uridine 5'-monophosphate based on adsorption methodology using a hyper-cross-linked resin.

    PubMed

    Wu, Jinglan; Zhu, Hui; Liu, Yanan; Zhou, Jingwei; Zhuang, Wei; Jiao, Pengfei; Ke, Xu; Ying, Hanjie

    2015-05-01

    The conventional ion exchange process used for recovery of uridine 5'-monophosphate (UMP) from the enzymatic hydrolysate of RNA is environmentally harmful and cost intensive. In this work, an innovative benign process, which comprises adsorption technology and use of a hyper-cross-linked resin as a stationary phase is proposed. The adsorption properties of this kind of resin in terms of adsorption equilibrium as well as kinetics were evaluated. The influences of the operating conditions, i.e., initial UMP concentration, feed flow rate, and bed height on the breakthrough curves of UMP in the fixed bed system were investigated. Subsequently, a chromatographic column model was established and validated for the prediction of the experimentally attained breakthrough curves of UMP and the main impurity component (phosphate ion) with a real enzymatic hydrolysate of RNA as a feed mixture. At the end of this paper, the crystallization of UMP was carried out. The purity of the final product (uridine 5'-monophosphate disodium, UMPNa2) of over 99.5 % was obtained.

  7. Chronic administration of docosahexaenoic acid or eicosapentaenoic acid, but not arachidonic acid, alone or in combination with uridine, increases brain phosphatide and synaptic protein levels in gerbils.

    PubMed

    Cansev, M; Wurtman, R J

    2007-08-24

    Synthesis of phosphatidylcholine, the most abundant brain membrane phosphatide, requires three circulating precursors: choline; a pyrimidine (e.g. uridine); and a polyunsaturated fatty acid. Supplementing a choline-containing diet with the uridine source uridine-5'-monophosphate (UMP) or, especially, with UMP plus the omega-3 fatty acid docosahexaenoic acid (given by gavage), produces substantial increases in membrane phosphatide and synaptic protein levels within gerbil brain. We now compare the effects of various polyunsaturated fatty acids, given alone or with UMP, on these synaptic membrane constituents. Gerbils received, daily for 4 weeks, a diet containing choline chloride with or without UMP and/or, by gavage, an omega-3 (docosahexaenoic or eicosapentaenoic acid) or omega-6 (arachidonic acid) fatty acid. Both of the omega-3 fatty acids elevated major brain phosphatide levels (by 18-28%, and 21-27%) and giving UMP along with them enhanced their effects significantly. Arachidonic acid, given alone or with UMP, was without effect. After UMP plus docosahexaenoic acid treatment, total brain phospholipid levels and those of each individual phosphatide increased significantly in all brain regions examined (cortex, striatum, hippocampus, brain stem, and cerebellum). The increases in brain phosphatides in gerbils receiving an omega-3 (but not omega-6) fatty acid, with or without UMP, were accompanied by parallel elevations in levels of pre- and post-synaptic proteins (syntaxin-3, PSD-95 and synapsin-1) but not in those of a ubiquitous structural protein, beta-tubulin. Hence administering omega-3 polyunsaturated fatty acids can enhance synaptic membrane levels in gerbils, and may do so in patients with neurodegenerative diseases, especially when given with a uridine source, while the omega-6 polyunsaturated fatty acid arachidonic acid is ineffective.

  8. Oral supplementation with docosahexaenoic acid and uridine-5'-monophosphate increases dendritic spine density in adult gerbil hippocampus.

    PubMed

    Sakamoto, Toshimasa; Cansev, Mehmet; Wurtman, Richard J

    2007-11-28

    Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid, is an essential component of membrane phosphatides and has been implicated in cognitive functions. Low levels of circulating or brain DHA are associated with various neurocognitive disorders including Alzheimer's disease (AD), while laboratory animals, including animal models of AD, can exhibit improved cognitive ability with a diet enriched in DHA. Various cellular mechanisms have been proposed for DHA's behavioral effects, including increases in cellular membrane fluidity, promotion of neurite extension and inhibition of apoptosis. However, there is little direct evidence that DHA affects synaptic structure in living animals. Here we show that oral supplementation with DHA substantially increases the number of dendritic spines in adult gerbil hippocampus, particularly when animals are co-supplemented with a uridine source, uridine-5'-monophosphate (UMP), which increases brain levels of the rate-limiting phosphatide precursor CTP. The increase in dendritic spines (>30%) is accompanied by parallel increases in membrane phosphatides and in pre- and post-synaptic proteins within the hippocampus. Hence, oral DHA may promote neuronal membrane synthesis to increase the number of synapses, particularly when co-administered with UMP. Our findings provide a possible explanation for the effects of DHA on behavior and also suggest a strategy to treat cognitive disorders resulting from synapse loss.

  9. Identification of proton-pump inhibitor drugs that inhibit Trichomonas vaginalis uridine nucleoside ribohydrolase.

    PubMed

    Shea, Tara A; Burburan, Paola J; Matubia, Vivian N; Ramcharan, Sandy S; Rosario, Irving; Parkin, David W; Stockman, Brian J

    2014-02-15

    Trichomonas vaginalis continues to be a major health problem with drug-resistant strains increasing in prevalence. Novel antitrichomonal agents that are mechanistically distinct from current therapies are needed. The NIH Clinical Compound Collection was screened to find inhibitors of the uridine ribohydrolase enzyme required by the parasite to scavenge uracil for its growth. The proton-pump inhibitors omeprazole, pantoprazole, and rabeprazole were identified as inhibitors of this enzyme, with IC50 values ranging from 0.3 to 14.5 μM. This suggests a molecular mechanism for the in vitro antitrichomonal activity of these proton-pump inhibitors, and may provide important insights toward structure-based drug design. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Chronic administration of docosahexaenoic acid or eicosapentaenoic acid, but not arachidonic acid, alone or in combination with uridine, increases brain phosphatide and synaptic protein levels in gerbils

    PubMed Central

    Cansev, M.; Wurtman, R. J.

    2007-01-01

    Synthesis of phosphatidylcholine, the most abundant brain membrane phosphatide, requires three circulating precursors: choline; a pyrimidine (e.g., uridine); and a polyunsaturated fatty acid. Supplementing a choline-containing diet with the uridine source uridine-5′-monophosphate (UMP) or, especially, with UMP plus the omega-3 fatty acid docosahexaenoic acid (given by gavage), produces substantial increases in membrane phosphatide and synaptic protein levels within gerbil brain. We now compare the effects of various polyunsaturated fatty acids, given alone or with UMP, on these synaptic membrane constituents. Gerbils received, daily for 4 weeks, a diet containing choline chloride with or without UMP and/or, by gavage, an omega-3 (docosahexaenoic or eicosapentaenoic acid) or omega-6 (arachidonic acid) fatty acid. Both of the omega-3 fatty acids elevated major brain phosphatide levels (by 18-28%, and 21-27%) and giving UMP along with them enhanced their effects significantly. Arachidonic acid, given alone or with UMP, was without effect. After UMP plus docosahexaenoic acid treatment, total brain phospholipids levels and those of each individual phosphatide increased significantly in all brain regions examined (cortex, striatum, hippocampus, brain stem, and cerebellum). The increases in brain phosphatides in gerbils receiving an omega-3 (but not omega-6) fatty acid, with or without UMP, were accompanied by parallel elevations in levels of pre- and post-synaptic proteins (syntaxin-3, PSD-95 and Synapsin-1) but not in those of a ubiquitous structural protein, β-tubulin. Hence administering omega-3 polyunsaturated fatty acids can enhance synaptic membrane levels in gerbils, and may do so in patients with neurodegenerative diseases, especially when given with a uridine source, while the omega-6 polyunsaturated fatty acid arachidonic acid is ineffective. PMID:17683870

  11. Improving the quality of infant sleep through the inclusion at supper of cereals enriched with tryptophan, adenosine-5'-phosphate, and uridine-5'-phosphate.

    PubMed

    Cubero, Javier; Chanclón, Belen; Sánchez, Soledad; Rivero, Montserrat; Rodríguez, Ana Beatriz; Barriga, Carmen

    2009-12-01

    The present study evaluated whether the administration of cereals enriched with nutrients that are facilitators of sleep could help improve the sleep of infants who had sleep disorders at night time. Thirty infants aged 8-16 months with sleep disorders involving at least three nocturnal waking episodes took part in the study. They were given a night-time 'sleep facilitating cereal' product containing 225 mg tryptophan, 5.3 mg adenosine-5'-P, and 6.3 mg uridine-5'-P per 100 g of product. These cereals were given in a double-blind procedure lasting 5 weeks, with ingestion of the cereal between 18:00 and 06:00. In the control week, the children received a standard cereal (75 mg tryptophan/100 g product without nucleotides) dissolved in a standard formula milk (231.5 mg tryptophan, 2.6 mg adenosine-5'-P, 5 mg uridine-5'-P, per 100 g product). In one experimental week, the children received the night-time sleep facilitating cereal together with the standard formula milk. In another week, they received the sleep facilitating cereal together with a night milk specially formulated to attain the sleep rhythm (480 mg tryptophan, 8.8 mg uridine-5'-P, and 7.6 mg adenosine-5'-P per 100 g product). The three experimental weeks were separated by two wash-out weeks in which the milk and cereal administered was identical in composition to that of the control week. All the infants received a programmed writer actimeter which they wore continually, attached to their ankles, to record their motor activity. The recorded activity was used to calculate information about the time in bed, assumed sleep, actual sleep, sleep efficiency, sleep latency, immobility, and total activity. The infants receiving the enriched cereal during the time of darkness showed improvements in their sleep parameters, regardless of whether the milk they took at night was standard or enriched with tryptophan, adenosine-5'-P, and uridine-5'-P. In summary, the administration of enriched cereals led to an

  12. Multi-temperature study of potassium uridine-5'-monophosphate: electron density distribution and anharmonic motion modelling.

    PubMed

    Jarzembska, Katarzyna N; Řlepokura, Katarzyna; Kamiński, Radosław; Gutmann, Matthias J; Dominiak, Paulina M; Woźniak, Krzysztof

    2017-08-01

    Uridine, a nucleoside formed of a uracil fragment attached to a ribose ring via a β-N1-glycosidic bond, is one of the four basic components of ribonucleic acid. Here a new anhydrous structure and experimental charge density distribution analysis of a uridine-5'-monophosphate potassium salt, K(UMPH), is reported. The studied case constitutes the very first structure of a 5'-nucleotide potassium salt according to the Cambridge Structural Database. The excellent crystal quality allowed the collection of charge density data at various temperatures, i.e. 10, 100, 200 and 300 K on one single crystal. Crystal structure and charge density data were analysed thoroughly in the context of related literature-reported examples. Detailed analysis of the charge density distribution revealed elevated anharmonic motion of part of the uracil ring moiety relatively weakly interacting with the neighbouring species. The effect was manifested by alternate positive and negative residual density patterns observed for these atoms, which `disappear' at low temperature. It also occurred that the potassium cation, quite uniformly coordinated by seven O atoms from all molecular fragments of the UMPH - anion, including the O atom from the ribofuranose ring, can be treated as spherical in the charge density model which was supported by theoretical calculations. Apart from the predominant electrostatic interactions, four relatively strong hydrogen bond types further support the stability of the crystal structure. This results in a compact and quite uniform structure (in all directions) of the studied crystal, as opposed to similar cases with layered architecture reported in the literature.

  13. Re-editing the paradigm of Cytidine (C) to Uridine (U) RNA editing.

    PubMed

    Fossat, Nicolas; Tam, Patrick P L

    2014-01-01

    Cytidine (C) to Uridine (U) RNA editing is a post-trancriptional modification that until recently was known to only affect Apolipoprotein b (Apob) RNA and minimally require 2 components of the C to U editosome, the deaminase APOBEC1 and the RNA-binding protein A1CF. Our latest work has identified a novel RNA-binding protein, RBM47, as a core component of the editosome, which can substitute A1CF for the editing of ApoB mRNA. In addition, new RNA species that are subjected to C to U editing have been identified. Here, we highlight these recent discoveries and discuss how they change our view of the composition of the C to U editing machinery and expand our knowledge of the functional attributes of C to U RNA editing.

  14. How many tautomerization pathways connect Watson-Crick-like G*·T DNA base mispair and wobble mismatches?

    PubMed

    Brovarets', Ol'ha O; Hovorun, Dmytro M

    2015-01-01

    In this study, we have theoretically demonstrated the intrinsic ability of the wobble G·T(w)/G*·T*(w)/G·T(w1)/G·T(w2) and Watson-Crick-like G*·T(WC) DNA base mispairs to interconvert into each other via the DPT tautomerization. We have established that among all these transitions, only one single G·T(w) ↔ G*·T(WC) pathway is eligible from a biological perspective. It involves short-lived intermediate - the G·T*(WC) base mispair - and is governed by the planar, highly stable, and zwitterionic [Formula: see text] transition state stabilized by the participation of the unique pattern of the five intermolecular O6(+)H⋯O4(-), O6(+)H⋯N3(-), N1(+)H⋯N3(-), N1(+)H⋯O2(-), and N2(+)H⋯O2(-) H-bonds. This non-dissociative G·T(w) ↔ G*·T(WC) tautomerization occurs without opening of the pair: Bases within mispair remain connected by 14 different patterns of the specific intermolecular interactions that successively change each other along the IRC. Novel kinetically controlled mechanism of the thermodynamically non-equilibrium spontaneous point GT/TG incorporation errors has been suggested. The mutagenic effect of the analogues of the nucleotide bases, in particular 5-bromouracil, can be attributed to the decreasing of the barrier of the acquisition by the wobble pair containing these compounds of the enzymatically competent Watson-Crick's geometry via the intrapair mutagenic tautomerization directly in the essentially hydrophobic recognition pocket of the replication DNA-polymerase machinery. Proposed approaches are able to explain experimental data, namely growth of the rate of the spontaneous point incorporation errors during DNA biosynthesis with increasing temperature.

  15. Binding of uridine 5'-diphosphate in the "basic patch" of the zinc deacetylase LpxC and implications for substrate binding.

    PubMed

    Gennadios, Heather A; Christianson, David W

    2006-12-26

    LpxC is a zinc metalloenzyme that catalyzes the first committed step in the biosynthesis of lipid A, a vital component of the outer membrane of Gram-negative bacteria. Accordingly, the inhibition of LpxC is an attractive strategy for the treatment of Gram-negative bacterial infections. Here, we report the 2.7 A resolution X-ray crystal structure of LpxC from Aquifex aeolicus complexed with uridine 5'-diphosphate (UDP), and the 3.1 A resolution structure of LpxC complexed with pyrophosphate. The X-ray crystal structure of the LpxC-UDP complex provides the first view of interactions likely to be exploited by the substrate UDP group in the "basic patch" of the active site. The diphosphate group of UDP makes hydrogen bond interactions with strictly conserved residue K239 as well as solvent molecules. The ribose moiety of UDP interacts with partially conserved residue E197. The UDP uracil group hydrogen bonds with both the backbone NH group and the backbone carbonyl group of E160, and with the backbone NH group of K162 through an intervening water molecule. Finally, the alpha-phosphate and uracil groups of UDP interact with R143 and R262 through intervening water molecules. The structure of LpxC complexed with pyrophosphate reveals generally similar intermolecular interactions in the basic patch. Unexpectedly, diphosphate binding in both complexes is accompanied by coordination to an additional zinc ion, resulting in the identification of a new metal-binding site termed the E-site. The structures of the LpxC-UDP and LpxC-pyrophosphate complexes provide new insights with regard to substrate recognition in the basic patch and metal ion coordination in the active site of LpxC.

  16. pyr RNA binding to the Bacillus caldolyticus PyrR attenuation protein. Characterization and regulation by uridine and guanosine nucleotides

    PubMed Central

    Jørgensen, Casper Møller; Fields, Christopher J.; Chander, Preethi; Watt, Desmond; Burgner, John W.; Smith, Janet L.; Switzer, Robert L.

    2011-01-01

    Summary The PyrR protein regulates expression of pyrimidine biosynthetic (pyr) genes in many bacteria. PyrR binds to specific sites in the 5’ leader RNA of target operons and favors attenuation of transcription. Filter binding and gel mobility assays were used to characterize the binding of PyrR from Bacillus caldolyticus to RNA sequences (binding loops) from the three attenuation regions of the B. caldolyticus pyr operon. Binding of PyrR to the three binding loops and modulation of RNA binding by nucleotides was similar for all three RNAs. Apparent dissociation constants at 0° C ranged from 0.13 to 0.87 nM in the absence of effectors; dissociation constants were decreased by 3 to 12 fold by uridine nucleotides and increased by 40 to 200 fold by guanosine nucleotides. The binding data suggest that pyr operon expression is regulated by the ratio of intracellular uridine nucleotides to guanosine nucleotides; the effects of nucleoside addition to the growth medium on aspartate transcarbamylase (pyrB) levels in B. subtilis cells in vivo supported this conclusion. Analytical ultracentrifugation established that RNA binds to dimeric PyrR, even though the tetrameric form of unbound PyrR predominates in solution at the concentrations studied. PMID:18190533

  17. Non-enzymatic synthesis of the coenzymes, uridine diphosphate glucose and cytidine diphosphate choline, and other phosphorylated metabolic intermediates

    NASA Technical Reports Server (NTRS)

    Mar, A.; Dworkin, J.; Oro, J.

    1987-01-01

    Using urea and cyanamide, the two condensing agents considered to have been present on the primitive earth, uridine diphosphate glucose (UDPG), cytidine diphosphate choline (CDP-choline), glucose-1-phosphate (G1P), and glucose-6-phosphate (G6P) were synthesized under simulated prebiotic conditions. The reaction products were separated and identified using paper chromatography, thin layer chromatography, enzymatic analyses, and ion-pair reverse-phase high performance liquid chromatography. The possibility of nonenzymatic synthesis of metabolic intermediates on the primitive earth from simple precursors was thus demonstrated.

  18. SU-E-T-666: Radionuclides and Activity of the Patient Apertures Used in a Proton Beam of Wobbling System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, B.Y.; Chen, H.H.; Tsai, H.Y.

    2015-06-15

    Purpose: To identify the radionuclides and quantify the activity of the patient apertures used in a 190-MeV proton beam of wobbling system. Methods: A proton beam of wobbling system in the first proton center in Taiwan, Chang Gung Memorial Hospital at Linkou, was used to bombard the patient apertures. The patient aperture was composed of 60.5 % copper, 39.4 % Zinc, 0.05 % iron, 0.05 % lead. A protable high-purity germanium (HPGe) coaxial detector was used to measure the spectra of the induced nuclides of patient apertures. The analysis of the spectra and the identification of the radionuclides were preliminarilymore » operated by the Nuclide Navigator III Master Library. On the basis of the results by Nuclide Navigator III Master Library, we manually selected the reliable nuclides by the gamma-ray energies, branching ratio, and half life. In the spectra, we can quantify the activity of radionuclides by the Monte Carlo efficiency transfer method. Results: In this study, the radioisotopes activated in patient apertures by the 190-MeV proton beam were divided into two categories. The first category is long half-life radionuclides, such as Co-56 (half life, 77.3 days). Other radionuclides of Cu-60, Cu-61, Cu-62, Cu-66, and Zn-62 have shorter half life. The radionuclide of Cu-60 had the highest activity. From calculation with the efficiency transfer method, the deviations between the computed results and the measured efficiencies were mostly within 10%. Conclusion: To identify the radionuclides and quantify the activity helps us to estimate proper time intervals for cooling the patient apertures. This study was supported by the grants from the Chang Gung Memorial Hospital (CMRPD1C0682)« less

  19. LKB1 promotes cell survival by modulating TIF-IA-mediated pre-ribosomal RNA synthesis under uridine downregulated conditions

    PubMed Central

    Liu, Xiuju; Huang, Henry; Wilkinson, Scott C.; Zhong, Diansheng; Khuri, Fadlo R.; Fu, Haian; Marcus, Adam; He, Yulong; Zhou, Wei

    2016-01-01

    We analyzed the mechanism underlying 5-aminoimidazole-4-carboxamide riboside (AICAR) mediated apoptosis in LKB1-null non-small cell lung cancer (NSCLC) cells. Metabolic profile analysis revealed depletion of the intracellular pyrimidine pool after AICAR treatment, but uridine was the only nucleotide precursor capable of rescuing this apoptosis, suggesting the involvement of RNA metabolism. Because half of RNA transcription in cancer is for pre-ribosomal RNA (rRNA) synthesis, which is suppressed by over 90% after AICAR treatment, we evaluated the role of TIF-IA-mediated rRNA synthesis. While the depletion of TIF-IA by RNAi alone promoted apoptosis in LKB1-null cells, the overexpression of a wild-type or a S636A TIF-IA mutant, but not a S636D mutant, attenuated AICAR-induced apoptosis. In LKB1-null H157 cells, pre-rRNA synthesis was not suppressed by AICAR when wild-type LKB1 was present, and cellular fractionation analysis indicated that TIF-IA quickly accumulated in the nucleus in the presence of a wild-type LKB1 but not a kinase-dead mutant. Furthermore, ectopic expression of LKB1 was capable of attenuating AICAR-induced death in AMPK-null cells. Because LKB1 promotes cell survival by modulating TIF-IA-mediated pre-rRNA synthesis, this discovery suggested that targeted depletion of uridine related metabolites may be exploited in the clinic to eliminate LKB1-null cancer cells. PMID:26506235

  20. LKB1 promotes cell survival by modulating TIF-IA-mediated pre-ribosomal RNA synthesis under uridine downregulated conditions.

    PubMed

    Liu, Fakeng; Jin, Rui; Liu, Xiuju; Huang, Henry; Wilkinson, Scott C; Zhong, Diansheng; Khuri, Fadlo R; Fu, Haian; Marcus, Adam; He, Yulong; Zhou, Wei

    2016-01-19

    We analyzed the mechanism underlying 5-aminoimidazole-4-carboxamide riboside (AICAR) mediated apoptosis in LKB1-null non-small cell lung cancer (NSCLC) cells. Metabolic profile analysis revealed depletion of the intracellular pyrimidine pool after AICAR treatment, but uridine was the only nucleotide precursor capable of rescuing this apoptosis, suggesting the involvement of RNA metabolism. Because half of RNA transcription in cancer is for pre-ribosomal RNA (rRNA) synthesis, which is suppressed by over 90% after AICAR treatment, we evaluated the role of TIF-IA-mediated rRNA synthesis. While the depletion of TIF-IA by RNAi alone promoted apoptosis in LKB1-null cells, the overexpression of a wild-type or a S636A TIF-IA mutant, but not a S636D mutant, attenuated AICAR-induced apoptosis. In LKB1-null H157 cells, pre-rRNA synthesis was not suppressed by AICAR when wild-type LKB1 was present, and cellular fractionation analysis indicated that TIF-IA quickly accumulated in the nucleus in the presence of a wild-type LKB1 but not a kinase-dead mutant. Furthermore, ectopic expression of LKB1 was capable of attenuating AICAR-induced death in AMPK-null cells. Because LKB1 promotes cell survival by modulating TIF-IA-mediated pre-rRNA synthesis, this discovery suggested that targeted depletion of uridine related metabolites may be exploited in the clinic to eliminate LKB1-null cancer cells.

  1. Detection of a pneumonia virus of mice (PVM) in an African hedgehog (Atelerix arbiventris) with suspected wobbly hedgehog syndrome (WHS).

    PubMed

    Madarame, Hiroo; Ogihara, Kikumi; Kimura, Moe; Nagai, Makoto; Omatsu, Tsutomu; Ochiai, Hideharu; Mizutani, Tetsyuya

    2014-09-17

    A pneumonia virus of mice (PVM) from an African hedgehog (Atelerix arbiventris) with suspected wobbly hedgehog syndrome (WHS) was detected and genetically characterized. The affected hedgehog had a nonsuppurative encephalitis with vacuolization of the white matter, and the brain samples yielded RNA reads highly homogeneous to PVM strain 15 (96.5% of full genomic sequence homology by analysis of next generation sequencing). PVM antigen was also detected in the brain and the lungs immunohistochemically. A PVM was strongly suggested as a causative agent of encephalitis of a hedgehog with suspected WHS. This is a first report of PVM infection in hedgehogs. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Synthesis, salvage, and catabolism of uridine nucleotides in boron-deficient squash roots.

    PubMed

    Lovatt, C J; Albert, L S; Tremblay, G C

    1981-12-01

    Previous work has provided evidence that plants may require boron to maintain adequate levels of pyrimidine nucleotides, suggesting that the state of boron deficiency may actually be one of pyrimidine starvation. Since the availability of pyrimidine nucleotides is influenced by their rates of synthesis, salvage, and catabolism, we compared these activities in the terminal 3 centimeters of roots excised from boron-deficient and -sufficient squash plants (Cucurbita pepo L.). Transferring 5-day-old squash plants to a boron-deficient nutrient solution resulted in cessation of root elongation within 18 hours. However, withholding boron for up to 30 hours did not result in either impaired de novo pyrimidine biosynthesis or a change in the sensitivity of the de novo pathway to regulation by end product inhibition. Boron deprivation had no significant effect on pyrimidine salvage or catabolism. These results provide evidence that boron-deficient plants are not starved for uridine nucleotides collectively. Whether a particular pyrimidine nucleotide or derivative is limiting during boron deprivation remains to be examined.

  3. Three-dimensional structures of unligated uridine phosphorylase from Yersinia pseudotuberculosis at 1.4 Å resolution and its complex with an antibacterial drug

    NASA Astrophysics Data System (ADS)

    Balaev, V. V.; Lashkov, A. A.; Gabdulkhakov, A. G.; Dontsova, M. V.; Mironov, A. S.; Betzel, C.; Mikhailov, A. M.

    2015-07-01

    Uridine phosphorylases play an essential role in the cellular metabolism of some antibacterial agents. Acute infectious diseases (bubonic plague, yersiniosis, pseudotuberculosis, etc., caused by bacteria of the genus Yersinia) are treated using both sulfanilamide medicines and antibiotics, including trimethoprim. The action of an antibiotic on a bacterial cell is determined primarily by the character of its interactions with cellular components, including those which are not targets (for example, with pyrimidine phosphorylases). This type of interaction should be taken into account in designing drugs. The three-dimensional structure of uridine phosphorylase from the bacterium Yersinia pseudotuberculosis ( YptUPh) with the free active site was determined for the first time by X-ray crystallography and refined at 1.40 Å resolution (DPI = 0.062 Å; ID PDB: 4OF4). The structure of the complex of YptUPh with the bacteriostatic drug trimethoprim was studied by molecular docking and molecular dynamics methods. The trimethoprim molecule was shown to be buffered by the enzyme YptUPh, resulting in a decrease in the efficiency of the treatment of infectious diseases caused by bacteria of the genus Yersinia with trimethoprim.

  4. Elongator-dependent modification of cytoplasmic tRNALysUUU is required for mitochondrial function under stress conditions

    PubMed Central

    Tigano, Marco; Ruotolo, Roberta; Dallabona, Cristina; Fontanesi, Flavia; Barrientos, Antoni; Donnini, Claudia; Ottonello, Simone

    2015-01-01

    To gain a wider view of the pathways that regulate mitochondrial function, we combined the effect of heat stress on respiratory capacity with the discovery potential of a genome-wide screen in Saccharomyces cerevisiae. We identified 105 new genes whose deletion impairs respiratory growth at 37°C by interfering with processes such as transcriptional regulation, ubiquitination and cytosolic tRNA wobble uridine modification via 5-methoxycarbonylmethyl-2-thiouridine formation. The latter process, specifically required for efficient decoding of AA-ending codons under stress conditions, was covered by multiple genes belonging to the Elongator (e.g. ELP3) and urmylation (e.g., NCS6) pathways. ELP3 or NCS6 deletants had impaired mitochondrial protein synthesis. Their respiratory deficiency was selectively rescued by overexpression of tRNALysUUU as well by overexpression of genes (BCK1 and HFM1) with a strong bias for the AAA codon read by this tRNA. These data extend the mitochondrial regulome, demonstrate that heat stress can impair respiration by disturbing cytoplasmic translation of proteins critically involved in mitochondrial function and document, for the first time, the involvement in such process of the Elongator and urmylation pathways. Given the conservation of these pathways, the present findings may pave the way to a better understanding of the human mitochondrial regulome in health and disease. PMID:26240381

  5. Diphtheria toxin can simultaneously bind to its receptor and adenylyl-(3',5')-uridine 3'-monophosphate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barbieri, J.T.; Collins, C.M.; Collier, R.J.

    1986-10-21

    Diphtheria toxin (DT) that was bound to receptors on BS-C-1 cells was able to bind approximately 1 molar equiv of adenylyl-(3',5')-uridine 3'-monophosphate (ApUp). In contrast, receptor-bound CRM197, a mutant form of toxin with greatly diminished affinity for dinucleotides, did not bind ApUp. Affinity of the dinucleotide for receptor-bound toxin differed from that for free toxin by less than an order of magnitude. These results indicate that the receptor site and the ApUp site on the toxin do not significantly overlap. BS-C-1 cells were incubated with or without /sup 125/I-DT or CRM 197. They were then incubated with (/sup 32/P)ApUp, andmore » assayed.« less

  6. Using Constraints from Satellite Gravimetry to Study Meteorological Excitations of the Chandler Wobble for an Earth Model with Frequency-dependent Responses

    NASA Astrophysics Data System (ADS)

    Chen, W.; Li, J.; Ray, J.; Cheng, M.; Chen, J.; Wilson, C. R.

    2015-12-01

    What maintain(s) the damping Chandler wobble (CW) is still under debate though meteorological excitations are now more preferred. However, controversial results have been obtained: Gross [2000] and Gross et al. [2003] suggested oceanic processes are more efficient to excite the CW than atmospheric ones during 1980 - 2000. Brzezinski and Nastula [2002] concluded that their contributions are almost the same, and they can only provide ~80% of the power needed to maintain the CW observed during 1985 - 1996. Polar motion excitations involve not only the perturbations within the Earth system (namely, mass redistributions and motions of relative to the mantle), but also the Earth's responses to those perturbations (namely, the rheology of the Earth). Chen et al. [2013a] developed an improved theory for polar motion excitation taking into account the Earth's frequency-dependent responses, of which the polar motion transfer functions are ~10% higher than those of previous theories around the CW band. Chen et al. [2013b] compared the geophysical excitations derived from various global atmospheric, oceanic and hydrological models (NCEP, ECCO, ERA40, ERAinterim and ECMWF operational products), and found significant and broad-band discrepancies for models released by different institutes. In addition, the atmosphere, ocean and hydrology models are usually developed in a somewhat independent manner and thus the global (atmospheric, oceanic and hydrological) mass is not conserved [e.g., Yan and Chao, 2012]. Therefore, the matter-term excitations estimated from those models are problematic. In one word, it is unlikely to obtain reliable conclusions on meteorological excitations of CW on the basis of the original meteorological models. Satellite gravimetry can measure mass transportations caused by atmospheric, oceanic and hydrological processes much more accurately than those provided by the original meteorological models, and can force the global (atmospheric, oceanic and

  7. Nutritional modifiers of aging brain function: Increasing the formation of brain synapses by administering uridine and other phosphatide precursors

    PubMed Central

    Wurtman, R.J.; Cansev, M; Sakamoto, T; Ulus, I.H.

    2010-01-01

    Brain phosphatide synthesis requires three circulating compounds: docosahexaenoic acid (DHA), uridine and choline. Oral administration of these phosphatide precursors to experimental animals increases the levels of phosphatides and synaptic proteins in the brain and per brain cell, as well as the numbers of dendritic spines on hippocampal neurons. Arachidonic acid (AA) fails to reproduce these effects of DHA. If similar increases occur in human brain, giving these compounds to patients with diseases – like Alzheimer’s disease – which cause the loss of brain synapses – could be beneficial. PMID:21091953

  8. The fate of H atom adducts to 3'-uridine monophosphate.

    PubMed

    Wang, Ran; Zhang, Ru Bo; Eriksson, Leif A

    2010-07-29

    The stabilities of the adducts deriving from H free radical addition to the O2, O4, and C5 positions of 3'-uridine monophosphate (3'UMP) are studied by the hybrid density functional B3LYP approach. Upon H atom addition at the O2 position, a concerted low-barrier proton-transfer process will initially occur, followed by the potential ruptures of the N-glycosidic or beta-phosphate bonds. The rupture barriers are strongly influenced by the rotational configuration of the phosphate group at the 3' terminal, and are influenced by bulk solvation effects. The O4-H adduct has the highest thermal stability, as the localization of the unpaired electron does not enable cleavage of either the C1'-N1 or the C3'-O(P) bonds. For the most stable adduct, with H atom added to the C5 position, the rate-controlled step is the H2'a abstraction by the C6 radical site, after which the subsequent strand rupture reactions proceed with low barriers. The main unpaired electron densities are presented for the transient species. Combined with previous results, it is concluded that the H atom adducts are more facile to drive the strand scission rather than N-glycosidic bond ruptures within the nucleic acid bases.

  9. Inferences from structural comparison: flexibility, secondary structure wobble and sequence alignment optimization.

    PubMed

    Zhang, Gaihua; Su, Zhen

    2012-01-01

    Work on protein structure prediction is very useful in biological research. To evaluate their accuracy, experimental protein structures or their derived data are used as the 'gold standard'. However, as proteins are dynamic molecular machines with structural flexibility such a standard may be unreliable. To investigate the influence of the structure flexibility, we analysed 3,652 protein structures of 137 unique sequences from 24 protein families. The results showed that (1) the three-dimensional (3D) protein structures were not rigid: the root-mean-square deviation (RMSD) of the backbone Cα of structures with identical sequences was relatively large, with the average of the maximum RMSD from each of the 137 sequences being 1.06 Å; (2) the derived data of the 3D structure was not constant, e.g. the highest ratio of the secondary structure wobble site was 60.69%, with the sequence alignments from structural comparisons of two proteins in the same family sometimes being completely different. Proteins may have several stable conformations and the data derived from resolved structures as a 'gold standard' should be optimized before being utilized as criteria to evaluate the prediction methods, e.g. sequence alignment from structural comparison. Helix/β-sheet transition exists in normal free proteins. The coil ratio of the 3D structure could affect its resolution as determined by X-ray crystallography.

  10. Introduction of antigenic determining 2,4-dinitrophenyl residues into 4-thiouridine, N3-(3-L-amino-3-carboxypropyl) uridine and tRNA-Phe from E. coli.

    PubMed Central

    Seela, F; Hansske, F; Watanabe, K; Cramer, F

    1977-01-01

    The introduction of antigenic determining 2,4-dinitrophenyl residues into the rare ribonucleosides 4-thiouridine (1a), and N3-(3-L-amino-3-carboxypropyl) uridine (2) as well as into tRNA-Phe from E. coli has been investigated. Alkylation of 1a with omega-bromo-2,4-dinitroacetophenone (3b) gives S-(2,4-dinitrophenacyl)-4-thiouridine (5A). Applying the reaction to the 5'-monophosphate of 1a, 5b is formed, but this product decomposes at pH 7. However, acylation of 2 with 2,4-dinitrobenzoic acid N-hydroxysuccinimide ester (4b) leads to N3-[3-carboxy-3-L-(2,4-dinitrobenzamido)propyl]uridine (6) which is stable in aqueous solution. The latter reaction was used for the introduction of an antigenic determining 2,4-dinitrophenyl residue into tRNA-Phe from E. coli. The modified tRNA-Phe was isolated and by degradation of the molecule with RNase T2 and alkaline phosphatase the nucleoside derivative 6 was obtained and found to be identical with the synthetic product. PMID:68463

  11. Interaction of 3‧,4‧,6‧-trimyristoyl-uridine derivative as potential anticancer drug with phospholipids of tumorigenic and non-tumorigenic cells

    NASA Astrophysics Data System (ADS)

    Salis, Luiz Fernando Grosso; Jaroque, Guilherme Nuñez; Escobar, Jhon Fernando Berrío; Giordani, Cristiano; Martinez, Alejandro Martinez; Fernández, Diana Margarita Márquez; Castelli, Francesco; Sarpietro, Maria Grazia; Caseli, Luciano

    2017-12-01

    Investigating the mechanism of action of drugs whose pharmaceutical activity is associated with cell membranes is fundamental to comprehending the biochemical and biophysical processes that occur on membrane surfaces. In this work, we investigated the interaction of an ester-type derivative of uridine, 3‧,4‧,6‧-trimyristoyl uridine, with models for cell membranes formed by lipid monolayers at the air-water interface. For that, selected lipids have been chosen in order to mimic tumorigenic and non-tumorigenic cells. For mixed monolayers with 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1,2-dihexadecanoyl-sn-glycero-3-phospho-L-serine (DPPS), the surface pressure-area isotherms exhibited a noticeable shift to lower areas in relation to the areas predicted for ideal mixtures, indicating a condensation of the monolayer structure. Changes in the viscoelastic properties of the interfacial film could be inferred by analyzing the compressibility modulus of the monolayer. Structural and morphological changes were also evidenced by using vibrational spectroscopy and Brewster angle microscopy, respectively, with distinctive effects on DPPC and DPPS. As conclusion we can state that the lipid composition of the monolayer modulates the interaction with this lipophilic drug, which may have important implications in understanding how this drug acts on specific sites of the cellular membrane.

  12. Bioconjugation of zirconium uridine monophosphate: application to myoglobin direct electrochemistry.

    PubMed

    Qiao, Yuanbiao; Jian, Fangfang; Bai, Qian

    2008-03-14

    Porous nano-granule of zirconium uridine monophosphate, Zr(UMP)2.H2O is, for the first time, synthesized under mild experimental conditions and applied to the bioconjugation of myoglobin (Mb) to realize its direct electron transfer. UV-vis and resonance Raman spectroscopies prove that Mb in the Zr(UMP)2.H2O film maintains its secondary structure similar to the native state. The conjugation film of the Mb-Zr(UMP)2.H2O on the glassy carbon (GC) electrode gives a well-defined and quasi-reversible cyclic voltammogram, which reflects the direct electron transfer of the heme Fe III/Fe II couple of Mb. On the basis of the satisfying bioelectrocatalysis of the nano-conjugation of Mb and genetic substrate, a kind of mediator-free biosensor for H2O2 is developed. The linear range for H2O2 detection is estimated to be 3.92-180.14 microM. The apparent Michaelis-Menten constant (Km) and the detection limit based on the signal-to-noise ratio of 3 are found to be 196.1 microM and 1.52 microM, respectively. Both the apparent Michaelis-Menten constant and the detection limit herein are much lower than currently reported values from other Mb films. This kind of sensor possesses excellent stability, long-term life (more than 20 days) and good reproducibility.

  13. Functional effects of uridine triphosphate on human skinned skeletal muscle fibers.

    PubMed

    Vianna-Jorge, R; Oliveira, C F; Mounier, Y; Suarez-Kurtz, G

    1998-02-01

    Chemically skinned human skeletal muscle fibers were used to study the effects of uridine triphosphate (UTP) on the tension-pCa relationship and on Ca2+ uptake and release by the sarcoplasmic reticulum (SR). Total replacement (2.5 mM) of adenosine triphosphate (ATP) with UTP (i) displaced the tension-pCa relationship to the left along the abcissae and increased maximum Ca(2+)-activated tension, both effects being larger in slow- than in fast-type fibers; (ii) markedly reduced Ca2+ uptake by the SR (evaluated by the caffeine-evoked tension) in both fiber types; (iii) had no effect on the rate of depletion of caffeine-sensitive Ca2+ stores during soaking in relaxing solutions; (iv) induced tension in slow- but not in fast-type fibers. The effects on the SR functional properties are consistent with the notion that UTP is a poor substitute for ATP as a substrate for the Ca ATPase pump and as an agonist of the ryanodine-sensitive Ca(2+)-release channel. The UTP-induced tension in human slow-type fibers is attributed to effect(s) of the nucleotide on the tension-pCa relationship of the contractile machinery. The present data reveal important differences between the effects of UTP on human versus rat muscle fibers.

  14. Supramolecular Assembly of Uridine Monophosphate (UMP) and Thymidine Monophosphate (TMP) with a Dinuclear Copper(II) Receptor.

    PubMed

    Rhaman, Md Mhahabubur; Powell, Douglas R; Hossain, Md Alamgir

    2017-11-30

    Understanding the intermolecular interactions between nucleotides and artificial receptors is crucial to understanding the role of nucleic acids in living systems. However, direct structural evidence showing precise interactions and bonding features of a nucleoside monophosphate (NMP) with a macrocycle-based synthetic molecule has not been provided so far. Herein, we present two novel crystal structures of uridine monophosphate (UMP) and thymidine monophosphate (TMP) complexes with a macrocycle-based dinuclear receptor. Structural characterization of these complexes reveals that the receptor recognizes UMP through coordinate-covalent interactions with phosphates and π-π stackings with nucleobases and TMP through coordinate-covalent interactions with phosphate groups. Furthermore, the receptor has been shown to effectively bind nucleoside monophosphates in the order of GMP > AMP > UMP > TMP > CMP in water at physiological pH, as investigated by an indicator displacement assay.

  15. Efficient heterologous expression and one-step purification of fully active c-terminal histidine-tagged uridine monophosphate kinase from Mycobacterium tuberculosis.

    PubMed

    Penpassakarn, Praweenuch; Chaiyen, Pimchai; Palittapongarnpim, Prasit

    2011-11-01

    Tuberculosis has long been recognized as one of the most significant public health problems. Finding novel antituberculous drugs is always a necessary approach for controlling the disease. Mycobacterium tuberculosis pyrH gene (Rv2883c) encodes for uridine monophosphate kinase (UMK), which is a key enzyme in the uridine nucleotide interconversion pathway. The enzyme is essential for M. tuberculosis to sustain growth and hence is a potential drug target. In this study, we have developed a rapid protocol for production and purification of M. tuberculosis UMK by cloning pyrH (Rv2883c) of M. tuberculosis H37Rv with the addition of 6-histidine residues to the C-terminus of the protein, and expressing in E. coli BL21-CodonPlus (DE3)-RIPL using an auto-induction medium. The enzyme was efficiently purified by a single-step TALON cobalt affinity chromatography with about 8 fold increase in specific activity, which was determined by a coupled assay with the pyruvate kinase and lactate dehydrogenase. The molecular mass of monomeric UMK was 28.2 kDa and that of the native enzyme was 217 kDa. The enzyme uses UMP as a substrate but not CMP and TMP and activity was enhanced by GTP. Measurements of enzyme kinetics revealed the kcat value of 7.6 +/- 0.4 U mg(-1) or 0.127 +/- 0.006 sec(-1).The protocol reported here can be used for expression of M. tuberculosis UMK in large quantity for formulating a high throughput target-based assay for screening anti-tuberculosis UMK compounds.

  16. Ion-exclusion chromatography determination of organic acid in uridine 5'-monophosphate fermentation broth.

    PubMed

    Niu, Huanqing; Chen, Yong; Xie, Jingjing; Chen, Xiaochun; Bai, Jianxin; Wu, Jinglan; Liu, Dong; Ying, Hanjie

    2012-09-01

    Simultaneous determination of organic acids using ion-exclusion liquid chromatography and ultraviolet detection is described. The chromatographic conditions are optimized when an Aminex HPX-87H column (300 × 7.8 mm) is employed, with a solution of 3 mmol/L sulfuric acid as eluent, a flow rate of 0.4 mL/min and a column temperature of 60°C. Eight organic acids (including orotic acid, α-ketoglutaric acid, citric acid, pyruvic acid, malic acid, succinic acid, lactic acid and acetic acid) and one nucleotide are successfully quantified. The calibration curves for these analytes are linear, with correlation coefficients exceeding 0.999. The average recovery of organic acids is in the range of 97.6% ∼ 103.1%, and the relative standard deviation is in the range of 0.037% ∼ 0.38%. The method is subsequently applied to obtain organic acid profiles of uridine 5'-monophosphate culture broth fermented from orotic acid by Saccharomyces cerevisiae. These data demonstrate the quantitative accuracy for nucleotide fermentation mixtures, and suggest that the method may also be applicable to other biological samples.

  17. Uridine 5'-Monophosphate Synthase Is Transcriptionally Regulated by Pyrimidine Levels in Nicotiana plumbaginifolia

    PubMed

    Santoso; Thornburg

    1998-02-01

    To understand the regulation and expression of pyrimidine biosynthesis in plants, we have examined the effect of the metabolic inhibitor 5-fluoroorotic acid (FOA) on uridine-5'-monophosphate synthase (UMPSase) expression in cell cultures of Nicotiana plumbaginifolia. UMPSase is the rate-limiting step of pyrimidine biosynthesis in plants. Addition of FOA causes an up-regulation of UMPSase enzyme activity in cell cultures after a lag phase of several days. Western-blot analysis demonstrated that the up-regulation in enzyme activity was caused by increased expression of the UMPSase protein. Northern-blot analysis demonstrated a higher level of UMPSase mRNA in the FOA-induced tissues than in control tissues. Run-on transcriptional assays showed that the UMPSase gene was transcriptionally activated after FOA treatment. The mechanism of toxicity of FOA is through thymine starvation. We found that addition of thymine abrogated the FOA-mediated up-regulation of UMPSase. In addition, methotrexate and aminopterin, which affect thymine levels by inhibiting dihydrofolate reductase, also up-regulate UMPSase in N. plumbaginifolia cells.

  18. Identification of cytidine 2',3'-cyclic monophosphate and uridine 2',3'-cyclic monophosphate in Pseudomonas fluorescens pfo-1 culture.

    PubMed

    Bordeleau, Emily; Oberc, Christopher; Ameen, Eve; da Silva, Amanda Mendes; Yan, Hongbin

    2014-09-15

    Cytidine 2',3'-cyclic monophosphate (2',3'-cCMP) and uridine 2',3'-cyclic monophosphate (2',3'-cUMP) were isolated from Pseudomonas fluorescens pfo-1 cell extracts by semi-preparative reverse phase HPLC. The structures of the two compounds were confirmed by NMR and mass spectroscopy against commercially available authentic samples. Concentrations of both intracellular and extracellular 2',3'-cCMP and 2',3'-cUMP were determined. Addition of 2',3'-cCMP and 2',3'-cUMP to P. fluorescens pfo-1 culture did not significantly affect the level of biofilm formation in static liquid cultures. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. rRNA fragmentation induced by a yeast killer toxin.

    PubMed

    Kast, Alene; Klassen, Roland; Meinhardt, Friedhelm

    2014-02-01

    Virus like dsDNA elements (VLE) in yeast were previously shown to encode the killer toxins PaT and zymocin, which target distinct tRNA species via specific anticodon nuclease (ACNase) activities. Here, we characterize a third member of the VLE-encoded toxins, PiT from Pichia inositovora, and identify PiOrf4 as the cytotoxic subunit by conditional expression in Saccharomyces cerevisiae. In contrast to the tRNA targeting toxins, however, neither a change of the wobble uridine modification status by introduction of elp3 or trm9 mutations nor tRNA overexpression rescued from PiOrf4 toxicity. Consistent with a distinct RNA target, expression of PiOrf4 causes specific fragmentation of the 25S and 18S rRNA. A stable cleavage product comprising the first ∼ 130 nucleotides of the 18S rRNA was purified and characterized by linker ligation and subsequent reverse transcription; 3'-termini were mapped to nucleotide 131 and 132 of the 18S rRNA sequence, a region showing some similarity to the anticodon loop of tRNA(Glu)(UUC), the zymocin target. PiOrf4 residues Glu9 and His214, corresponding to catalytic sites Glu9 and His209 in the ACNase subunit of zymocin are essential for in vivo toxicity and rRNA fragmentation, raising the possibility of functionally conserved RNase modules in both proteins. © 2013 John Wiley & Sons Ltd.

  20. Elongator-dependent modification of cytoplasmic tRNALysUUU is required for mitochondrial function under stress conditions.

    PubMed

    Tigano, Marco; Ruotolo, Roberta; Dallabona, Cristina; Fontanesi, Flavia; Barrientos, Antoni; Donnini, Claudia; Ottonello, Simone

    2015-09-30

    To gain a wider view of the pathways that regulate mitochondrial function, we combined the effect of heat stress on respiratory capacity with the discovery potential of a genome-wide screen in Saccharomyces cerevisiae. We identified 105 new genes whose deletion impairs respiratory growth at 37°C by interfering with processes such as transcriptional regulation, ubiquitination and cytosolic tRNA wobble uridine modification via 5-methoxycarbonylmethyl-2-thiouridine formation. The latter process, specifically required for efficient decoding of AA-ending codons under stress conditions, was covered by multiple genes belonging to the Elongator (e.g. ELP3) and urmylation (e.g., NCS6) pathways. ELP3 or NCS6 deletants had impaired mitochondrial protein synthesis. Their respiratory deficiency was selectively rescued by overexpression of tRNA(Lys) UUU as well by overexpression of genes (BCK1 and HFM1) with a strong bias for the AAA codon read by this tRNA. These data extend the mitochondrial regulome, demonstrate that heat stress can impair respiration by disturbing cytoplasmic translation of proteins critically involved in mitochondrial function and document, for the first time, the involvement in such process of the Elongator and urmylation pathways. Given the conservation of these pathways, the present findings may pave the way to a better understanding of the human mitochondrial regulome in health and disease. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  1. Nonenzymatic template-directed synthesis on hairpin oligonucleotides. 3. Incorporation of adenosine and uridine residues

    NASA Technical Reports Server (NTRS)

    Wu, T.; Orgel, L. E.

    1992-01-01

    We have used [32P]-labeled hairpin oligonucleotides to study template-directed synthesis on templates containing one or more A or T residues within a run of C residues. When nucleoside-5'-phosphoro(2-methyl)imidazolides are used as substrates, isolated A and T residues function efficiently in facilitating the incorporation of U and A, respectively. The reactions are regiospecific, producing mainly 3'-5'-phosphodiester bonds. Pairs of consecutive non-C residues are copied much less efficiently. Limited synthesis of CA and AC sequences on templates containing TG and GT sequences was observed along with some synthesis of the AA sequences on templates containing TT sequences. The other dimer sequences investigated, AA, AG, GA, TA, and AT, could not be copied. If A is absent from the reaction mixture, misincorporation of G residues is a significant reaction on templates containing an isolated T residue or two consecutive T residues. However, if both A and G are present, A is incorporated to a much greater extent than G. We believe that wobble-pairing between T and G is responsible for misincorporation when only G is present.

  2. Syn- and anti-conformations of 5'-deoxy- and 5'-O-methyl-uridine 2',3'-cyclic monophosphate.

    PubMed

    Grabarkiewicz, Tomasz; Hoffmann, Marcin

    2006-01-01

    Two uridine 2',3'-cyclic monophosphate (cUMP) derivatives, 5'-deoxy (DcUMP) and 5'-O-methyl (McUMP), were studied by means of quantum chemical methods. Aqueous solvent effects were estimated based on the isodensity-surface polarized-continuum model (IPCM). Gas phase calculations revealed only slight energy differences between the syn- and anti-conformers of both compounds: the relative energies of the syn-structure are -0.9 and 0.2 kcal mol(-1) for DcUMP and McUMP, respectively. According to the results from the IPCM calculations, however, both syn-conformers become about 14 kcal mol(-1) more stable in aqueous solution than their corresponding anti-structures. Additionally, the effects of a countercation and protonation on DcUMP were studied, revealing that the syn-structure is also favored over the anti-one for these systems.

  3. Supramolecular Assembly of Uridine Monophosphate (UMP) and Thymidine Monophosphate (TMP) with a Dinuclear Copper(II) Receptor

    PubMed Central

    2017-01-01

    Understanding the intermolecular interactions between nucleotides and artificial receptors is crucial to understanding the role of nucleic acids in living systems. However, direct structural evidence showing precise interactions and bonding features of a nucleoside monophosphate (NMP) with a macrocycle-based synthetic molecule has not been provided so far. Herein, we present two novel crystal structures of uridine monophosphate (UMP) and thymidine monophosphate (TMP) complexes with a macrocycle-based dinuclear receptor. Structural characterization of these complexes reveals that the receptor recognizes UMP through coordinate–covalent interactions with phosphates and π–π stackings with nucleobases and TMP through coordinate–covalent interactions with phosphate groups. Furthermore, the receptor has been shown to effectively bind nucleoside monophosphates in the order of GMP > AMP > UMP > TMP > CMP in water at physiological pH, as investigated by an indicator displacement assay. PMID:29214233

  4. Intestinal alkaline phosphatase inhibits the proinflammatory nucleotide uridine diphosphate.

    PubMed

    Moss, Angela K; Hamarneh, Sulaiman R; Mohamed, Mussa M Rafat; Ramasamy, Sundaram; Yammine, Halim; Patel, Palak; Kaliannan, Kanakaraju; Alam, Sayeda N; Muhammad, Nur; Moaven, Omeed; Teshager, Abeba; Malo, Nondita S; Narisawa, Sonoko; Millán, José Luis; Warren, H Shaw; Hohmann, Elizabeth; Malo, Madhu S; Hodin, Richard A

    2013-03-15

    Uridine diphosphate (UDP) is a proinflammatory nucleotide implicated in inflammatory bowel disease. Intestinal alkaline phosphatase (IAP) is a gut mucosal defense factor capable of inhibiting intestinal inflammation. We used the malachite green assay to show that IAP dephosphorylates UDP. To study the anti-inflammatory effect of IAP, UDP or other proinflammatory ligands (LPS, flagellin, Pam3Cys, or TNF-α) in the presence or absence of IAP were applied to cell cultures, and IL-8 was measured. UDP caused dose-dependent increase in IL-8 release by immune cells and two gut epithelial cell lines, and IAP treatment abrogated IL-8 release. Costimulation with UDP and other inflammatory ligands resulted in a synergistic increase in IL-8 release, which was prevented by IAP treatment. In vivo, UDP in the presence or absence of IAP was instilled into a small intestinal loop model in wild-type and IAP-knockout mice. Luminal contents were applied to cell culture, and cytokine levels were measured in culture supernatant and intestinal tissue. UDP-treated luminal contents induced more inflammation on target cells, with a greater inflammatory response to contents from IAP-KO mice treated with UDP than from WT mice. Additionally, UDP treatment increased TNF-α levels in intestinal tissue of IAP-KO mice, and cotreatment with IAP reduced inflammation to control levels. Taken together, these studies show that IAP prevents inflammation caused by UDP alone and in combination with other ligands, and the anti-inflammatory effect of IAP against UDP persists in mouse small intestine. The benefits of IAP in intestinal disease may be partly due to inhibition of the proinflammatory activity of UDP.

  5. Intestinal alkaline phosphatase inhibits the proinflammatory nucleotide uridine diphosphate

    PubMed Central

    Hamarneh, Sulaiman R.; Mohamed, Mussa M. Rafat; Ramasamy, Sundaram; Yammine, Halim; Patel, Palak; Kaliannan, Kanakaraju; Alam, Sayeda N.; Muhammad, Nur; Moaven, Omeed; Teshager, Abeba; Malo, Nondita S.; Narisawa, Sonoko; Millán, José Luis; Warren, H. Shaw; Hohmann, Elizabeth; Malo, Madhu S.; Hodin, Richard A.

    2013-01-01

    Uridine diphosphate (UDP) is a proinflammatory nucleotide implicated in inflammatory bowel disease. Intestinal alkaline phosphatase (IAP) is a gut mucosal defense factor capable of inhibiting intestinal inflammation. We used the malachite green assay to show that IAP dephosphorylates UDP. To study the anti-inflammatory effect of IAP, UDP or other proinflammatory ligands (LPS, flagellin, Pam3Cys, or TNF-α) in the presence or absence of IAP were applied to cell cultures, and IL-8 was measured. UDP caused dose-dependent increase in IL-8 release by immune cells and two gut epithelial cell lines, and IAP treatment abrogated IL-8 release. Costimulation with UDP and other inflammatory ligands resulted in a synergistic increase in IL-8 release, which was prevented by IAP treatment. In vivo, UDP in the presence or absence of IAP was instilled into a small intestinal loop model in wild-type and IAP-knockout mice. Luminal contents were applied to cell culture, and cytokine levels were measured in culture supernatant and intestinal tissue. UDP-treated luminal contents induced more inflammation on target cells, with a greater inflammatory response to contents from IAP-KO mice treated with UDP than from WT mice. Additionally, UDP treatment increased TNF-α levels in intestinal tissue of IAP-KO mice, and cotreatment with IAP reduced inflammation to control levels. Taken together, these studies show that IAP prevents inflammation caused by UDP alone and in combination with other ligands, and the anti-inflammatory effect of IAP against UDP persists in mouse small intestine. The benefits of IAP in intestinal disease may be partly due to inhibition of the proinflammatory activity of UDP. PMID:23306083

  6. Enhanced uridine 5'-monophosphate production by whole cell of Saccharomyces cerevisiae through rational redistribution of metabolic flux.

    PubMed

    Liu, Dong; Chen, Yong; Li, An; Xie, Jingjing; Xiong, Jian; Bai, Jianxin; Chen, Xiaochun; Niu, Huanqing; Zhou, Tao; Ying, Hanjie

    2012-06-01

    A whole-cell biocatalytic process for uridine 5'-monophosphate (UMP) production from orotic acid by Saccharomyces cerevisiae was developed. To rationally redistribute the metabolic flux between glycolysis and pentose phosphate pathway, statistical methods were employed first to find out the critical factors in the process. NaH(2)PO(4), MgCl(2) and pH were found to be the important factors affecting UMP production significantly. The levels of these three factors required for the maximum production of UMP were determined: NaH(2)PO(4) 22.1 g/L; MgCl(2) 2.55 g/L; pH 8.15. An enhancement of UMP production from 6.12 to 8.13 g/L was achieved. A significant redistribution of metabolic fluxes was observed and the underlying mechanism was discussed.

  7. Reparameterization of RNA chi Torsion Parameters for the AMBER Force Field and Comparison to NMR Spectra for Cytidine and Uridine.

    PubMed

    Yildirim, Ilyas; Stern, Harry A; Kennedy, Scott D; Tubbs, Jason D; Turner, Douglas H

    2010-05-11

    A reparameterization of the torsional parameters for the glycosidic dihedral angle, chi, for the AMBER99 force field in RNA nucleosides is used to provide a modified force field, AMBER99chi. Molecular dynamics simulations of cytidine, uridine, adenosine, and guanosine in aqueous solution using the AMBER99 and AMBER99chi force fields are compared with NMR results. For each nucleoside and force field, 10 individual molecular dynamics simulations of 30 ns each were run. For cytidine with AMBER99chi force field, each molecular dynamics simulation time was extended to 120 ns for convergence purposes. Nuclear magnetic resonance (NMR) spectroscopy, including one-dimensional (1D) (1)H, steady-state 1D (1)H nuclear Overhauser effect (NOE), and transient 1D (1)H NOE, was used to determine the sugar puckering and preferred base orientation with respect to the ribose of cytidine and uridine. The AMBER99 force field overestimates the population of syn conformations of the base orientation and of C2'-endo sugar puckering of the pyrimidines, while the AMBER99chi force field's predictions are more consistent with NMR results. Moreover, the AMBER99 force field prefers high anti conformations with glycosidic dihedral angles around 310 degrees for the base orientation of purines. The AMBER99chi force field prefers anti conformations around 185 degrees , which is more consistent with the quantum mechanical calculations and known 3D structures of folded ribonucleic acids (RNAs). Evidently, the AMBER99chi force field predicts the structural characteristics of ribonucleosides better than the AMBER99 force field and should improve structural and thermodynamic predictions of RNA structures.

  8. On the Observation of Discrete Fluorine NMR Spectra for Uridine 5′-β,γ-Fluoromethylenetriphosphate Diastereomers at Basic pH

    PubMed Central

    2015-01-01

    Jakeman et al. recently reported the inability to distinguish the diastereomers of uridine 5′-β,γ-fluoromethylenetriphosphate (β,γ-CHF-UTP, 1) by 19F NMR under conditions we previously prescribed for the resolution of the corresponding β,γ-CHF-dGTP spectra, stating further that 1 decomposed under these basic conditions. Here we show that the 19F NMR spectra of 1 (∼1:1 diastereomer mixture prepared by coupling of UMP-morpholidate with fluoromethylenebis(phosphonic acid)) in D2O at pH 10 are indeed readily distinguishable. 1 in this solution was stable for 24 h at rt. PMID:24819695

  9. The Cytidine Analog Fluorocyclopentenylcytosine (RX-3117) Is Activated by Uridine-Cytidine Kinase 2

    PubMed Central

    Smid, Kees; de Klerk, Daniël; van Kuilenburg, André B. P.; Meinsma, Rutger; Lee, Young B.; Kim, Deog J.; Peters, Godefridus J.

    2016-01-01

    Fluorocyclopentenylcytosine (RX-3117) is an orally available cytidine analog, currently in Phase I clinical trial. RX-3117 has promising antitumor activity in various human tumor xenografts including gemcitabine resistant tumors. RX-3117 is activated by uridine-cytidine kinase (UCK). Since UCK exists in two forms, UCK1 and UCK2, we investigated which form is responsible for RX-3117 phosphorylation. For that purpose we transfected A549 and SW1573 cell lines with UCK-siRNAs. Transfection of UCK1-siRNA efficiently downregulated UCK1-mRNA, but not UCK2-mRNA expression, and did not affect sensitivity to RX-3117. However, transfection of UCK2-siRNA completely downregulated UCK2-mRNA and protein and protected both A549 and SW1573 against RX-3117. UCK enzyme activity in two panels of tumor cell lines and xenograft cells correlated only with UCK2-mRNA expression (r = 0.803 and 0.915, respectively), but not with UCK1-mRNA. Moreover, accumulation of RX-3117 nucleotides correlated with UCK2 expression. In conclusion, RX-3117 is activated by UCK2 which may be used to select patients potentially sensitive to RX-3117. PMID:27612203

  10. Strain in shock-loaded skeletal muscle and the time scale of muscular wobbling mass dynamics.

    PubMed

    Christensen, Kasper B; Günther, Michael; Schmitt, Syn; Siebert, Tobias

    2017-10-16

    In terrestrial locomotion, muscles undergo damped oscillations in response to limb impacts with the ground. Muscles are also actuators that generate mechanical power to allow locomotion. The corresponding elementary contractile process is the work stroke of an actin-myosin cross-bridge, which may be forcibly detached by superposed oscillations. By experimentally emulating rat leg impacts, we found that full activity and non-fatigue must meet to possibly prevent forcible cross-bridge detachment. Because submaximal muscle force represents the ordinary locomotor condition, our results show that forcible, eccentric cross-bridge detachment is a common, physiological process even during isometric muscle contractions. We also calculated the stiffnesses of the whole muscle-tendon complex and the fibre material separately, as well as Young's modulus of the latter: 1.8 MPa and 0.75 MPa for fresh, fully active and passive fibres, respectively. Our inferred Young's modulus of the tendon-aponeurosis complex suggests that stiffness in series to the fibre material is determined by the elastic properties of the aponeurosis region, rather than the tendon material. Knowing these stiffnesses and the muscle mass, the complex' eigenfrequency for responses to impacts can be quantified, as well as the size-dependency of this time scale of muscular wobbling mass dynamics.

  11. Idiosyncratic recognition of UUG/UUA codons by modified nucleoside 5-taurinomethyluridine, τm5U present at 'wobble' position in anticodon loop of tRNALeu: A molecular modeling approach.

    PubMed

    Kamble, Asmita S; Fandilolu, Prayagraj M; Sambhare, Susmit B; Sonawane, Kailas D

    2017-01-01

    Lack of naturally occurring modified nucleoside 5-taurinomethyluridine (τm5U) at the 'wobble' 34th position in tRNALeu causes mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). The τm5U34 specifically recognizes UUG and UUA codons. Structural consequences of τm5U34 to read cognate codons have not been studied so far in detail at the atomic level. Hence, 50ns multiple molecular dynamics (MD) simulations of various anticodon stem loop (ASL) models of tRNALeu in presence and absence of τm5U34 along with UUG and UUA codons were performed to explore the dynamic behaviour of τm5U34 during codon recognition process. The MD simulation results revealed that τm5U34 recognizes G/A ending codons by 'wobble' as well as a novel 'single' hydrogen bonding interactions. RMSD and RMSF values indicate the comparative stability of the ASL models containing τm5U34 modification over the other models, lacking τm5U34. Another MD simulation study of 55S mammalian mitochondrial rRNA with tRNALeu showed crucial interactions between the A-site residues, A918, A919, G256 and codon-anticodon bases. Thus, these results could improve our understanding about the decoding efficiency of human mt tRNALeu with τm5U34 to recognize UUG and UUA codons.

  12. Application of the isotope-dilution principle to the analysis of factors affecting the incorporation of [3H]uridine and [3H]cytidine into cultured lymphocytes. Evaluation of pools in serum and culture media

    PubMed Central

    Forsdyke, D. R.

    1971-01-01

    1. Rat lymph-node cells were incubated in serum and medium 199 with [5-3H]uridine or [5-3H]cytidine and acid-precipitable radioactivity was measured. Results were interpreted in terms of an isotope-dilution model. 2. Both serum and medium 199 contained pools that inhibited radioactive labelling in a competitive manner. The serum activity was diffusible and inhibited labelling with [3H]cytidine more than with [3H]uridine; in these respects the activity resembled cytidine (14μm). 3. The pools in serum and plasma were the same size; however, the rate of labelling was greater in plasma, owing to a diffusible factor. 4. Paradoxically, relatively simple media (Earle's salts and Eagle's minimum essential) appeared to have a larger pool than the more complex pyrimidine-containing medium 199; this suggests a contribution to the pool by cells in the simple media. 5. In the absence of pools the average cell was capable of incorporating 2000 radioactive nucleoside molecules/s. PMID:4947658

  13. The mechanisms of citrate on regulating the distribution of carbon flux in the biosynthesis of uridine 5'-monophosphate by Saccharomyces cerevisiae.

    PubMed

    Chen, Yong; Li, Shuya; Xiong, Jian; Li, Zhenjiang; Bai, Jianxin; Zhang, Lei; Ye, Qi; Ouyang, Pingkai; Ying, Hanjie

    2010-03-01

    A whole cell biocatalytic process for uridine 5'-monophosphate (UMP) production from orotic acid by Saccharomyces cerevisiae was developed. The concentration of UMP was increased by 23% when 1 g l(-1) sodium citrate was fed into the broth. Effects of citrate addition on UMP production were investigated. Glucose-6-phosphate pool was elevated by onefold, while FBP and pyruvate were decreased by 42% and 40%, respectively. Organic acid pools such as acetate and succinate were averagely decreased by 30% and 49%. The results demonstrated that manipulation of citrate levels could be used as a novel tool to regulate the metabolic fluxes distribution among glycolysis, pentose phosphate pathway, and TCA cycle.

  14. Modeling of a possible conformational change associated with the catalytic mechanism in the hammerhead ribozyme

    NASA Technical Reports Server (NTRS)

    Setlik, R. F.; Shibata, M.; Sarma, R. H.; Sarma, M. H.; Kazim, A. L.; Ornstein, R. L.; Tomasi, T. B.; Rein, R.

    1995-01-01

    Here we describe a possible model of the cleavage mechanism in the hammerhead ribozyme. In this model, the 2' hydroxyl of C17 is moved into an appropriate orientation for an in-line attack on the G1.1 phosphate through a change in its sugar pucker from C3' endo to C2' endo. This conformational change in the active site is caused by a change in the uridine turn placing the N2 and N3 atoms of G5 of the conserved core in hydrogen bonding geometry with the N3 and N2 atoms on the conserved G16.2 residue. The observed conformational change in the uridine turn suggests an explanation for the conservation of G5. In the crystal structure of H.M. Pley et al., Nature 372, 68-74 (1994), G5 is situated 5.3A away from G16.2. However, the uridine turn is sufficiently flexible to allow this conformational change with relatively modest changes in the backbone torsion angles (average change of 14.2 degrees). Two magnesium ions were modeled into the active site with positions analogous to those described in the functionally similar Klenow fragment 3'-5' exonuclease (L.S. Beese and T.A. Steitz, EMBO J. 10, 25-33 (1991)), the Group I intron (T.A. Steitz and J.A. Steitz, P.N.A.S. U.S.A. 90, 6498-6502 (1993); R.F. Setlik et al., J. Biomol. Str. Dyn. 10, 945-972 (1993)) and other phosphotransferases. Comparison of this model with one in which the uridine turn conformation was not changed showed that although the changes in the C17 sugar pucker could be modeled, insufficient space existed for the magnesium ions in the active site.

  15. In Silico Discovery of Potential Uridine-Cytidine Kinase 2 Inhibitors from the Rhizome of Alpinia mutica.

    PubMed

    Malami, Ibrahim; Abdul, Ahmad Bustamam; Abdullah, Rasedee; Bt Kassim, Nur Kartinee; Waziri, Peter; Christopher Etti, Imaobong

    2016-04-08

    Uridine-cytidine kinase 2 is implicated in uncontrolled proliferation of abnormal cells and it is a hallmark of cancer, therefore, there is need for effective inhibitors of this key enzyme. In this study, we employed the used of in silico studies to find effective UCK2 inhibitors of natural origin using bioinformatics tools. An in vitro kinase assay was established by measuring the amount of ADP production in the presence of ATP and 5-fluorouridine as a substrate. Molecular docking studies revealed an interesting ligand interaction with the UCK2 protein for both flavokawain B and alpinetin. Both compounds were found to reduce ADP production, possibly by inhibiting UCK2 activity in vitro. In conclusion, we have identified flavokawain B and alpinetin as potential natural UCK2 inhibitors as determined by their interactions with UCK2 protein using in silico molecular docking studies. This can provide information to identify lead candidates for further drug design and development.

  16. Coordinating properties of uridine 5'-monophosphate with selected Ln(3+) ions in ionic micellar media.

    PubMed

    Sudhiranjan Singh, M; Homendra, Naorem; Lonibala, R K

    2012-12-01

    Coordinating properties of uridine 5'-monophosphate (UMP) towards trivalent La, Pr, Nd, Sm, Eu and Gd ions in presence of cationic and anionic micelles have been investigated by potentiometric pH-titration and spectroscopic methods. Stability constants of the 2:1 complexes have been determined and the change in free energy, enthalpy and entropy associated with the complexation are also calculated. Nd(III) complexes isolated from aqueous and aqueous-micellar media do not show any significant structural difference. Formation of Ln(III) complexes in all cases completes below pH 7.5 showing that UMP best interacts with Ln(3+) ions at the physiological pH range 7.3-7.5. The nucleobase is not involved in the complexation and the metal ion coordination of UMP is through the phosphate moiety only. Coordinating tendency of UMP with lanthanides, Nd(III) ion in particular, at different pH is also discussed. Luminescent properties of Eu(III) complex and its decay lifetime are also presented. This information may prove helpful regarding the use of lanthanides as biological probes for calcium/magnesium ions.

  17. Uridine 5′-Monophosphate Synthase Is Transcriptionally Regulated by Pyrimidine Levels in Nicotiana plumbaginifolia1

    PubMed Central

    Santoso, Djoko; Thornburg, Robert

    1998-01-01

    To understand the regulation and expression of pyrimidine biosynthesis in plants, we have examined the effect of the metabolic inhibitor 5-fluoroorotic acid (FOA) on uridine-5′-monophosphate synthase (UMPSase) expression in cell cultures of Nicotiana plumbaginifolia. UMPSase is the rate-limiting step of pyrimidine biosynthesis in plants. Addition of FOA causes an up-regulation of UMPSase enzyme activity in cell cultures after a lag phase of several days. Western-blot analysis demonstrated that the up-regulation in enzyme activity was caused by increased expression of the UMPSase protein. Northern-blot analysis demonstrated a higher level of UMPSase mRNA in the FOA-induced tissues than in control tissues. Run-on transcriptional assays showed that the UMPSase gene was transcriptionally activated after FOA treatment. The mechanism of toxicity of FOA is through thymine starvation. We found that addition of thymine abrogated the FOA-mediated up-regulation of UMPSase. In addition, methotrexate and aminopterin, which affect thymine levels by inhibiting dihydrofolate reductase, also up-regulate UMPSase in N. plumbaginifolia cells. PMID:9490773

  18. An ensemble of paired spin(-1/2) nuclei in a rotating solid: Polarization evolution and NMR spectrum in a wobbling frame.

    PubMed

    Kundla, Enn

    2007-04-01

    The evolution of the magnetic polarization of an ensemble of paired spin(-1/2) nuclei in an MAS NMR (nuclear magnetic resonance) experiment and the induced spectrum are described theoretically by means of a Liouville-von Neumann equation representation in a wobbling rotating frame in combination with the averaged Hamiltonian theory. In this method, the effect of a high-intensity external static magnetic field and the effects of the leftover interaction components of the Hamiltonian that commute with the approximate Hamiltonian are taken into account simultaneously and equivalently. This method reproduces details that really exist in the recorded spectra, caused by secular terms in the Hamiltonian, which might otherwise be smoothed out owing to the approximate treatment of the effects of the secular terms. Complete analytical expressions, which describe the whole NMR spectrum including the rotational sideband sets, and which consider all the relevant intermolecular interactions, are obtained.

  19. Isolation, crystallization in the macrogravitation field, preliminary X-ray investigation of uridine phosphorylase from Escherichia coli K-12.

    PubMed

    Mikhailov, A M; Smirnova, E A; Tsuprun, V L; Tagunova, I V; Vainshtein, B K; Linkova, E V; Komissarov, A A; Siprashvili, Z Z; Mironov, A S

    1992-03-01

    Uridine phosphorylase (UPH) from Escherichia coli K-12 has been purified to near homogeneity from a strain harbouring the udp gene, encoding UPH, on a multicopy plasmid. UPH was purified to electrophoretic homogeneity with the specific activity 230 units/mg with a recovery of 80%, yielding 120 mg of enzyme from 3g cells. Crystals of enzyme suitable for X-ray diffraction analysis were obtained in a preparative ultracentrifuge. The packing of the molecules in the crystals may be described by the space group P2(1)2(1)2(1) with the unit cell constants a = 90.4; b = 128.8; c = 136.8 A. There is one molecule per asymmetric unit, Vm = 2.4. These crystals diffract to at least 2.5-2.7 A resolution. The hexameric structure of UPH was directly demonstrated by electron microscopy study and image processing.

  20. Electrostatics Explains the Position-Dependent Effect of G⋅U Wobble Base Pairs on the Affinity of RNA Kissing Complexes.

    PubMed

    Abi-Ghanem, Josephine; Rabin, Clémence; Porrini, Massimiliano; Dausse, Eric; Toulmé, Jean-Jacques; Gabelica, Valérie

    2017-10-06

    In the RNA realm, non-Watson-Crick base pairs are abundant and can affect both the RNA 3D structure and its function. Here, we investigated the formation of RNA kissing complexes in which the loop-loop interaction is modulated by non-Watson-Crick pairs. Mass spectrometry, surface plasmon resonance, and UV-melting experiments show that the G⋅U wobble base pair favors kissing complex formation only when placed at specific positions. We tried to rationalize this effect by molecular modeling, including molecular mechanics Poisson-Boltzmann surface area (MMPBSA) thermodynamics calculations and PBSA calculations of the electrostatic potential surfaces. Modeling reveals that the G⋅U stabilization is due to a specific electrostatic environment defined by the base pairs of the entire loop-loop region. The loop is not symmetric, and therefore the identity and position of each base pair matters. Predicting and visualizing the electrostatic environment created by a given sequence can help to design specific kissing complexes with high affinity, for potential therapeutic, nanotechnology or analytical applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Effects of dietary uridine 5'-monophosphate on immune responses in newborn calves.

    PubMed

    Mashiko, T; Nagafuchi, S; Kanbe, M; Obara, Y; Hagawa, Y; Takahashi, T; Katoh, K

    2009-03-01

    When compared with normal milk, bovine colostrum contains a large amount of uridine 5'-monophosphate (UMP) and its derivatives. In the present study, we carried out 2 experiments to determine the effects of dietary UMP (2 g/d) on the immune status of newborn calves. In Exp. 1, newborn Holstein bull calves were fed milk replacer alone (control group) or milk replacer supplemented with UMP (UMP group) from d 4 to 10 after birth. The increase in interferon-gamma concentration by peripheral blood mononuclear cells (PBMC) on d 24 tended to be greater in the UMP group than in the control group (P = 0.06). The IgA concentration of the ileal mucosa was greater in the UMP group than in the control group (P < 0.05), although there was no difference between groups in the jejunal mucosa. In Exp. 2, newborn Holstein bull calves were fed milk replacer alone (control group) or milk replacer supplemented with UMP (UMP group) from d 4 to 56 after birth. The proliferation of PBMC was greater in the UMP group than in the control group on d 14, 28, and 42 (P < 0.01). The increase in interferon-gamma concentration by PBMC was greater in the UMP group than in the control group on d 28 and 42 (P < 0.05). From these results, we concluded that dietary UMP affected the immune responses of newborn calves.

  2. Wobbling The Galactic Disk with Bombardment of Satellite Galaxies

    NASA Astrophysics Data System (ADS)

    D'Onghia, Elena

    We propose to assess the effect of impacts of large visible satellite galaxies on a disk, as well as the relevance of the continuing bombardment of the Galactic disk by dark matter clumps as predicted by the current cosmological framework that can wobble the disk, heating it and eventually exciting ragged spiral structures. In particular, we make detailed predictions for observable features such as spiral arms, rings and their associated stars in galactic disks and relate them to the physical processes that drive their formation and evolution in our Milky Way galaxy and nearby spirals. To do this, we will combine analytic methods and numerical simulations that allow us to calculate observables, which we will compare to present and forthcoming observations. Our methodology utilizes a combination of state of the art hydrodynamic simulations of galaxy evolution and multi- wavelength radiative transfer simulations. Our primary goals are: (1) To identify the physical processes that are responsible for spiral structure formation observed in our Milky Way and nearby disk galaxies, from the flocculent to grand- designed spiral galaxies and to provide observable signatures to be compared with data on nearby galaxies combining maps of 24 micron emission (Spitzer) and cold gas, CO (Heracles) and HI (THINGS). (2) To explore different morphologies of spiral galaxies: from the multi-armed galaxies to the Milky Way sized galaxies with few arms. (3) For a Milky Way disk we will assess the effect of impacts of substructures passing through the disk to origin the asymmetry in the number density of stars recently discovered from SDSS and SEGUE data and confirmed from RAVE data. We will also investigate the disk heating in the vertical plane due to the formation of vertical oscillations that are produced by the impact and migration of stars in the disk as consequence of the heating as compared to the classical stellar migration mechanism. (4) We will measure the spiral pattern speed

  3. 5-Substituents in the uridine moiety and their effect on the conformation of ApU-type dinucleoside phosphates.

    PubMed

    Hillen, W; Gassen, G

    1978-03-29

    The ApU analogues ApT, Apcl5U, Apbr5U, Apa5U and Apno5(2)U were synthesized with the aid of ribonuclease U2 starting from 2',3'-cyclic Ap and the respective uridine derivatives. For these compounds the ultraviolet data, the difference spectra, the hypochromism and the temperature dependence of the CD spectra are reported. The dimerisation shifts of the pyrimidine protons which were obtained from the 100 MHz PMR spectra confirm the optical results. The influence of the substituents in the 5 position of the uracil ring on base-base interaction and the conformation of the dinucleoside phosphates is discussed with respect to the van der Waals radii and the electronic effects of these groups. As calculated from the hypochromism the dinucleoside phosphates can be arranged according to decreasing base-base interaction: Apno5(2)U greater than Apbr5U approximately ApT greater than Apcl5U greater than ApU greater than Apa5U.

  4. A nonradioactive high-performance liquid chromatographic microassay for uridine 5'-monophosphate synthase, orotate phosphoribosyltransferase, and orotidine 5'-monophosphate decarboxylase.

    PubMed

    Krungkrai, J; Wutipraditkul, N; Prapunwattana, P; Krungkrai, S R; Rochanakij, S

    2001-12-15

    A novel nonradioactive, microassay method has been developed to determine simultaneously the two enzymatic activities of orotate phosphoribosyltransferase (OPRTase) and orotidine 5'-monophosphate decarboxylase (ODCase), either as a bifunctional protein (uridine 5'-monophosphate synthase, UMPS) or as separate enzymes. Substrates (orotate for OPRTase or orotidine 5'-monophosphate for ODCase) and a product (UMP) of the enzymatic assay were separated by high-performance liquid chromatography (HPLC) using a reversed-phase column and an ion-pairing system; the amount of UMP was quantified by dual-wavelength uv detection at 260 and 278 nm. This HPLC assay can easily detect picomole levels of UMP in enzymatic reactions using low specific activity UMPS of mammalian cell extracts, which is difficult to do with the other nonradioactive assays that have been described. The HPLC assay is suitable for use in protein purification and for kinetic study of these enzymes. (c)2001 Elsevier Science.

  5. Influence of 5-HALOGENATION on the Structure of Protonated Uridine: Irmpd Action Spectroscopy and Theoretical Studies of the Protonated 5-HALOURIDINES

    NASA Astrophysics Data System (ADS)

    Roy, Harrison; Hamlow, Lucas; Lee, Justin; Rodgers, M. T.; Berden, Giel; Oomens, Jos

    2016-06-01

    The chemical and structural diversity and the extent of post-transcriptional modification of RNA is remarkable! Presently, there are 142 different naturally-occurring and many more synthetically modified nucleosides known. Uridine (Urd) is the most commonly modified nucleoside among those that occur naturally, but has also been an important target for synthesis and development of modified nucleosides for pharmaceutical applications. Indeed, modified nucleosides are of pharmaceutical interest due to their bioactivities. In particular, 5-bromouridine (br5Urd) has been shown to exhibit antiviral activity to human immunodeficiency virus and has been used in RNA labeling studies. Halogenation is a common modification employed in pharmaceutical studies that enables systematic variation is the electronic properties of the molecule of interest due to the availability of halogen substituents that vary in size, dipole moment, polarizability, and electron withdrawing properties. In order to elucidate the influence of 5-halogenation on the intrinsic gas-phase structure and stability on the protonated form of Urd, synergistic spectroscopic and theoretical studies of the protonated forms of the 5-halouridines are performed here, where x5Urd = 5-fluorouridine (f5Urd), 5-chlorouridine (cl5Urd), br5Urd, and 5-iodouridine (i5Urd). Infrared multiple photon dissociation (IRMPD) action spectra of the protonated forms of the 5-halouridines, [x5Urd+H]+, are measured over the IR fingerprint region using the FELIX free electron laser and the hydrogen stretching region using an OPO/OPA laser from 3300-3800 wn. Complementary electronic structure calculations are performed to determine the stable low-energy conformations available to these species and to predict their IR spectra. Comparative analyses of the measured IRMPD spectra and predicted IR spectra are performed to elucidate the preferred sites of protonation, and the low-energy tautomeric conformations that are populated by

  6. Incidence of bovine leukocyte adhesion deficiency, complex vertebral malformation, and deficiency of uridine-5-monophosphate synthase carriers in Brazilian Girolando cattle.

    PubMed

    Paiva, D S; Fonseca, I; Pinto, I S B; Ianella, P; Campos, T A; Caetano, A R; Paiva, S R; Silva, M V G B; Martins, M F

    2013-08-29

    Among the various hereditary diseases that have been widely studied in dairy cattle, bovine leukocyte adhesion deficiency (BLAD), deficiency of uridine-5-monophosphate synthase (DUMPS), and complex vertebral malformation (CVM) are noteworthy because of their high impact on overall herd productivity as a consequence of increased calf mortality. The aim of this study was to verify the frequency of carriers of BLAD, CVM, and DUMPS mutant alleles in cows and bulls from the National Girolando Progeny Test carried out in Brazil by using polymerase chain reaction (PCR)-restriction fragment length polymorphism and allele-specific PCR assays. A total of 777 animals were genotyped for BLAD, 783 for CVM, and 122 for DUMPS. The frequencies of carriers for BLAD and CVM were 0.77 and 1.53%, respectively, whereas no carriers of DUMPS were observed.

  7. Human tRNA(Lys3)(UUU) is pre-structured by natural modifications for cognate and wobble codon binding through keto-enol tautomerism.

    PubMed

    Vendeix, Franck A P; Murphy, Frank V; Cantara, William A; Leszczyńska, Grażyna; Gustilo, Estella M; Sproat, Brian; Malkiewicz, Andrzej; Agris, Paul F

    2012-03-02

    Human tRNA(Lys3)(UUU) (htRNA(Lys3)(UUU)) decodes the lysine codons AAA and AAG during translation and also plays a crucial role as the primer for HIV-1 (human immunodeficiency virus type 1) reverse transcription. The posttranscriptional modifications 5-methoxycarbonylmethyl-2-thiouridine (mcm(5)s(2)U(34)), 2-methylthio-N(6)-threonylcarbamoyladenosine (ms(2)t(6)A(37)), and pseudouridine (Ψ(39)) in the tRNA's anticodon domain are critical for ribosomal binding and HIV-1 reverse transcription. To understand the importance of modified nucleoside contributions, we determined the structure and function of this tRNA's anticodon stem and loop (ASL) domain with these modifications at positions 34, 37, and 39, respectively (hASL(Lys3)(UUU)-mcm(5)s(2)U(34);ms(2)t(6)A(37);Ψ(39)). Ribosome binding assays in vitro revealed that the hASL(Lys3)(UUU)-mcm(5)s(2)U(34);ms(2)t(6)A(37);Ψ(39) bound AAA and AAG codons, whereas binding of the unmodified ASL(Lys3)(UUU) was barely detectable. The UV hyperchromicity, the circular dichroism, and the structural analyses indicated that Ψ(39) enhanced the thermodynamic stability of the ASL through base stacking while ms(2)t(6)A(37) restrained the anticodon to adopt an open loop conformation that is required for ribosomal binding. The NMR-restrained molecular-dynamics-derived solution structure revealed that the modifications provided an open, ordered loop for codon binding. The crystal structures of the hASL(Lys3)(UUU)-mcm(5)s(2)U(34);ms(2)t(6)A(37);Ψ(39) bound to the 30S ribosomal subunit with each codon in the A site showed that the modified nucleotides mcm(5)s(2)U(34) and ms(2)t(6)A(37) participate in the stability of the anticodon-codon interaction. Importantly, the mcm(5)s(2)U(34)·G(3) wobble base pair is in the Watson-Crick geometry, requiring unusual hydrogen bonding to G in which mcm(5)s(2)U(34) must shift from the keto to the enol form. The results unambiguously demonstrate that modifications pre-structure the anticodon as a key

  8. Determination of Ion Atmosphere Effects on the Nucleic Acid Electrostatic Potential and Ligand Association Using AH+·C Wobble Formation in Double-Stranded DNA

    PubMed Central

    2017-01-01

    The high charge density of nucleic acids and resulting ion atmosphere profoundly influence the conformational landscape of RNA and DNA and their association with small molecules and proteins. Electrostatic theories have been applied to quantitatively model the electrostatic potential surrounding nucleic acids and the effects of the surrounding ion atmosphere, but experimental measures of the potential and tests of these models have often been complicated by conformational changes and multisite binding equilibria, among other factors. We sought a simple system to further test the basic predictions from electrostatics theory and to measure the energetic consequences of the nucleic acid electrostatic field. We turned to a DNA system developed by Bevilacqua and co-workers that involves a proton as a ligand whose binding is accompanied by formation of an internal AH+·C wobble pair [Siegfried, N. A., et al. Biochemistry, 2010, 49, 3225]. Consistent with predictions from polyelectrolyte models, we observed logarithmic dependences of proton affinity versus salt concentration of −0.96 ± 0.03 and −0.52 ± 0.01 with monovalent and divalent cations, respectively, and these results help clarify prior results that appeared to conflict with these fundamental models. Strikingly, quantitation of the ion atmosphere content indicates that divalent cations are preferentially lost over monovalent cations upon A·C protonation, providing experimental indication of the preferential localization of more highly charged cations to the inner shell of the ion atmosphere. The internal AH+·C wobble system further allowed us to parse energetic contributions and extract estimates for the electrostatic potential at the position of protonation. The results give a potential near the DNA surface at 20 mM Mg2+ that is much less substantial than at 20 mM K+ (−120 mV vs −210 mV). These values and difference are similar to predictions from theory, and the potential is substantially reduced at

  9. The Biosynthesis of Capuramycin-type Antibiotics: IDENTIFICATION OF THE A-102395 BIOSYNTHETIC GENE CLUSTER, MECHANISM OF SELF-RESISTANCE, AND FORMATION OF URIDINE-5'-CARBOXAMIDE.

    PubMed

    Cai, Wenlong; Goswami, Anwesha; Yang, Zhaoyong; Liu, Xiaodong; Green, Keith D; Barnard-Britson, Sandra; Baba, Satoshi; Funabashi, Masanori; Nonaka, Koichi; Sunkara, Manjula; Morris, Andrew J; Spork, Anatol P; Ducho, Christian; Garneau-Tsodikova, Sylvie; Thorson, Jon S; Van Lanen, Steven G

    2015-05-29

    A-500359s, A-503083s, and A-102395 are capuramycin-type nucleoside antibiotics that were discovered using a screen to identify inhibitors of bacterial translocase I, an essential enzyme in peptidoglycan cell wall biosynthesis. Like the parent capuramycin, A-500359s and A-503083s consist of three structural components: a uridine-5'-carboxamide (CarU), a rare unsaturated hexuronic acid, and an aminocaprolactam, the last of which is substituted by an unusual arylamine-containing polyamide in A-102395. The biosynthetic gene clusters for A-500359s and A-503083s have been reported, and two genes encoding a putative non-heme Fe(II)-dependent α-ketoglutarate:UMP dioxygenase and an l-Thr:uridine-5'-aldehyde transaldolase were uncovered, suggesting that C-C bond formation during assembly of the high carbon (C6) sugar backbone of CarU proceeds from the precursors UMP and l-Thr to form 5'-C-glycyluridine (C7) as a biosynthetic intermediate. Here, isotopic enrichment studies with the producer of A-503083s were used to indeed establish l-Thr as the direct source of the carboxamide of CarU. With this knowledge, the A-102395 gene cluster was subsequently cloned and characterized. A genetic system in the A-102395-producing strain was developed, permitting the inactivation of several genes, including those encoding the dioxygenase (cpr19) and transaldolase (cpr25), which abolished the production of A-102395, thus confirming their role in biosynthesis. Heterologous production of recombinant Cpr19 and CapK, the transaldolase homolog involved in A-503083 biosynthesis, confirmed their expected function. Finally, a phosphotransferase (Cpr17) conferring self-resistance was functionally characterized. The results provide the opportunity to use comparative genomics along with in vivo and in vitro approaches to probe the biosynthetic mechanism of these intriguing structures. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. A 2'-deoxy-2'-fluoro-2'-C-methyl uridine cyclopentyl carbocyclic analog and its phosphoramidate prodrug as inhibitors of HCV NS5B polymerase.

    PubMed

    Liu, Jian; Du, Jinfa; Wang, Peiyuan; Nagarathnam, Dhanapalan; Espiritu, Christine L; Bao, Haiying; Murakami, Eisuke; Furman, Phillip A; Sofia, Michael J

    2012-04-01

    The 2 '-deoxy-2 '-fluoro-2 '-C-methyluridine nucleotide prodrug, PSI-7851 and its single diastereomer PSI-7977 have displayed potent antiviral activity against hepatitis C virus in clinical trials, and PSI-7977 is currently in Phase III studies. As part of our SAR study of the 2 '-deoxy-2 '-fluoro-2 '- C-methyl class of nucleosides, we prepared the cyclopentyl carbocyclic uridine analog 11 and its phosphoramidate prodrug 15. Both 11 and 15 were shown not to inhibit HCV replication. This lack of activity might be attributed to the inability of the monophosphate to be converted to the corresponding diphosphate or triphosphate or the inactivity of triphosphate of 11 as an inhibitor of the polymerase.

  11. tRNA1Ser(G34) with the anticodon GGA can recognize not only UCC and UCU codons but also UCA and UCG codons.

    PubMed

    Yamada, Yuko; Matsugi, Jitsuhiro; Ishikura, Hisayuki

    2003-04-15

    The tRNA1Ser (anticodon VGA, V=uridin-5-oxyacetic acid) is essential for translation of the UCA codon in Escherichia coli. Here, we studied the translational abilities of serine tRNA derivatives, which have different bases from wild type at the first positions of their anticodons, using synthetic mRNAs containing the UCN (N=A, G, C, or U) codon. The tRNA1Ser(G34) having the anticodon GGA was able to read not only UCC and UCU codons but also UCA and UCG codons. This means that the formation of G-A or G-G pair allowed at the wobble position and these base pairs are noncanonical. The translational efficiency of the tRNA1Ser(G34) for UCA or UCG codon depends on the 2'-O-methylation of the C32 (Cm). The 2'-O-methylation of C32 may give rise to the space necessary for G-A or G-G base pair formation between the first position of anticodon and the third position of codon.

  12. Novel modes of RNA editing in mitochondria

    PubMed Central

    Moreira, Sandrine; Valach, Matus; Aoulad-Aissa, Mohamed; Otto, Christian; Burger, Gertraud

    2016-01-01

    Abstract Gene structure and expression in diplonemid mitochondria are unparalleled. Genes are fragmented in pieces (modules) that are separately transcribed, followed by the joining of module transcripts to contiguous RNAs. Some instances of unique uridine insertion RNA editing at module boundaries were noted, but the extent and potential occurrence of other editing types remained unknown. Comparative analysis of deep transcriptome and genome data from Diplonema papillatum mitochondria reveals ∼220 post-transcriptional insertions of uridines, but no insertions of other nucleotides nor deletions. In addition, we detect in total 114 substitutions of cytosine by uridine and adenosine by inosine, amassed into unusually compact clusters. Inosines in transcripts were confirmed experimentally. This is the first report of adenosine-to-inosine editing of mRNAs and ribosomal RNAs in mitochondria. In mRNAs, editing causes mostly amino-acid additions and non-synonymous substitutions; in ribosomal RNAs, it permits formation of canonical secondary structures. Two extensively edited transcripts were compared across four diplonemids. The pattern of uridine-insertion editing is strictly conserved, whereas substitution editing has diverged dramatically, but still rendering diplonemid proteins more similar to other eukaryotic orthologs. We posit that RNA editing not only compensates but also sustains, or even accelerates, ultra-rapid evolution of genome structure and sequence in diplonemid mitochondria. PMID:27001515

  13. Orotate phosphoribosyl transferase MoPyr5 is involved in uridine 5'-phosphate synthesis and pathogenesis of Magnaporthe oryzae.

    PubMed

    Qi, Zhongqiang; Liu, Muxing; Dong, Yanhan; Yang, Jie; Zhang, Haifeng; Zheng, Xiaobo; Zhang, Zhengguang

    2016-04-01

    Orotate phosphoribosyl transferase (OPRTase) plays an important role in de novo and salvage pathways of nucleotide synthesis and is widely used as a screening marker in genetic transformation. However, the function of OPRTase in plant pathogens remains unclear. In this study, we characterized an ortholog of Saccharomyces cerevisiae Ura5, the OPRTase MoPyr5, from the rice blast fungus Magnaporthe oryzae. Targeted gene disruption revealed that MoPyr5 is required for mycelial growth, appressorial turgor pressure and penetration into plant tissues, invasive hyphal growth, and pathogenicity. Interestingly, the ∆Mopyr5 mutant is also involved in mycelial surface hydrophobicity. Exogenous uridine 5'-phosphate (UMP) restored vegetative growth and rescued the defect in pathogenicity on detached barley and rice leaf sheath. Collectively, our results show that MoPyr5 is an OPRTase for UMP biosynthesis in M. oryzae and indicate that UTP biosynthesis is closely linked with vegetative growth, cell wall integrity, and pathogenicity of fungus. Our results also suggest that UMP biosynthesis would be a good target for the development of novel fungicides against M. oryzae.

  14. S-Geranyl-2-thiouridine wobble nucleosides of bacterial tRNAs; chemical and enzymatic synthesis of S-geranylated-RNAs and their physicochemical characterization

    PubMed Central

    Sierant, Malgorzata; Leszczynska, Grazyna; Sadowska, Klaudia; Dziergowska, Agnieszka; Rozanski, Michal; Sochacka, Elzbieta; Nawrot, Barbara

    2016-01-01

    Recently, highly lipophilic S-geranylated derivatives of 5-methylaminomethyl-2-thiouridine (mnm5geS2U) and 5-carboxymethylaminomethyl-2-thiouridine (cmnm5geS2U) were found at the first (wobble) anticodon position in bacterial tRNAs specific for Lys, Glu and Gln. The function and cellular biogenesis of these unique tRNAs remain poorly understood. Here, we present one direct and two post-synthetic chemical routes for preparing model geS2U-RNAs. Our experimental data demonstrate that geS2U-RNAs are more lipophilic than their parent S2U-RNAs as well as non-modified U-RNAs. Thermodynamic studies revealed that the S-geranyl-2-thiouridine-containing RNA has higher affinity toward complementary RNA strand with G opposite the modified unit than with A. Recombinant tRNA selenouridine synthase (SelU) exhibits sulfur-specific geranylation activity toward model S2U-RNA, which is composed of the anticodon-stem-loop (ASL) from the human tRNALys3 sequence. In addition, the presence of magnesium ions is required to achieve appreciable geranylation efficiencies. PMID:27566149

  15. Uridine monophosphate kinase as potential target for tuberculosis: from target to lead identification.

    PubMed

    Arvind, Akanksha; Jain, Vaibhav; Saravanan, Parameswaran; Mohan, C Gopi

    2013-12-01

    Mycobacterium tuberculosis (Mtb) is a causative agent of tuberculosis (TB) disease, which has affected approximately 2 billion people worldwide. Due to the emergence of resistance towards the existing drugs, discovery of new anti-TB drugs is an important global healthcare challenge. To address this problem, there is an urgent need to identify new drug targets in Mtb. In the present study, the subtractive genomics approach has been employed for the identification of new drug targets against TB. Screening the Mtb proteome using the Database of Essential Genes (DEG) and human proteome resulted in the identification of 60 key proteins which have no eukaryotic counterparts. Critical analysis of these proteins using Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways database revealed uridine monophosphate kinase (UMPK) enzyme as a potential drug target for developing novel anti-TB drugs. Homology model of Mtb-UMPK was constructed for the first time on the basis of the crystal structure of E. coli-UMPK, in order to understand its structure-function relationships, and which would in turn facilitate to perform structure-based inhibitor design. Furthermore, the structural similarity search was carried out using physiological inhibitor UTP of Mtb-UMPK to virtually screen ZINC database. Retrieved hits were further screened by implementing several filters like ADME and toxicity followed by molecular docking. Finally, on the basis of the Glide docking score and the mode of binding, 6 putative leads were identified as inhibitors of this enzyme which can potentially emerge as future drugs for the treatment of TB.

  16. A catalytic metal ion interacts with the cleavage site G•U wobble in the HDV ribozyme†

    PubMed Central

    Chen, Jui-Hui; Gong, Bo; Bevilacqua, Philip C.; Carey, Paul R.; Golden, Barbara L.

    2009-01-01

    The HDV ribozyme self-cleaves by a chemical mechanism involving general acid-base catalysis to generate a 2′,3′-cyclic phosphate and a 5′-hydroxyl termini. Biochemical studies from several laboratories have implicated C75 as the general acid and hydrated magnesium as the general base. We have previously shown that C75 has a pKa shifted > 2 pH units toward neutrality [Gong, B., Chen, J. H., Chase, E., Chadalavada, D. M., Yajima, R., Golden, B. L., Bevilacqua, P. C., and Carey, P. R. (2007) J. Am. Chem. Soc. 129, 13335–13342.], while in crystal structures, it is well-positioned for proton transfer. However no crystallographic evidence for a hydrated magnesium poised to serve as a general base in the reaction has been observed in high-resolution crystal structures of various reaction states and mutants. Herein, we use solution kinetic experiments and parallel Raman crystallographic studies to examine the effects of pH on rate and Mg2+-binding properties of wild-type and 7-deazaguanosine mutants of the HDV ribozyme. These data suggest that a previously-unobserved hydrated magnesium ion interacts with the N7 of the cleavage site G•U wobble base pair. Integrating this metal ion binding site with the available crystal structures provides a new three-dimensional model for the active site of the ribozyme that accommodates all available biochemical data and appears competent for catalysis. The position of this metal is consistent with a role of a magnesium-bound hydroxide as a general base as dictated by biochemical data. PMID:19178151

  17. A catalytic metal ion interacts with the cleavage Site G.U wobble in the HDV ribozyme.

    PubMed

    Chen, Jui-Hui; Gong, Bo; Bevilacqua, Philip C; Carey, Paul R; Golden, Barbara L

    2009-02-24

    The HDV ribozyme self-cleaves by a chemical mechanism involving general acid-base catalysis to generate 2',3'-cyclic phosphate and 5'-hydroxyl termini. Biochemical studies from several laboratories have implicated C75 as the general acid and hydrated magnesium as the general base. We have previously shown that C75 has a pK(a) shifted >2 pH units toward neutrality [Gong, B., Chen, J. H., Chase, E., Chadalavada, D. M., Yajima, R., Golden, B. L., Bevilacqua, P. C., and Carey, P. R. (2007) J. Am. Chem. Soc. 129, 13335-13342], while in crystal structures, it is well-positioned for proton transfer. However, no evidence for a hydrated magnesium poised to serve as a general base in the reaction has been observed in high-resolution crystal structures of various reaction states and mutants. Herein, we use solution kinetic experiments and parallel Raman crystallographic studies to examine the effects of pH on the rate and Mg(2+) binding properties of wild-type and 7-deazaguanosine mutants of the HDV ribozyme. These data suggest that a previously unobserved hydrated magnesium ion interacts with N7 of the cleavage site G.U wobble base pair. Integrating this metal ion binding site with the available crystal structures provides a new three-dimensional model for the active site of the ribozyme that accommodates all available biochemical data and appears competent for catalysis. The position of this metal is consistent with a role of a magnesium-bound hydroxide as a general base as dictated by biochemical data.

  18. Book Review: Precession, Nutation, and Wobble of the Earth

    NASA Astrophysics Data System (ADS)

    Sterken, Christiaan; Dehant, V.; Mathews, P. M.

    2016-10-01

    This great book describes and explains observational and computational aspects of three apparently tiny changes in the Earth's motion and orientation, viz., precession, nutation, and wobble. The three introductory chapters of this book present fundamental definitions, elementary geodetic theory, and celestial/terrestrial reference systems - including transformations between reference frames. The next chapter on observational techniques describes the principle of accurate measurements of the orientation of the Earth's axis, as obtained from measurements of extra-galactic radio sources using Very Long Baseline Interferometry and GPS observations. Chapter 5 handles precession and nutation of the rigid Earth (i.e., a celestial body that cannot, by definition, deform) and the subsequent chapter takes deformation into consideration, viz., the effect of a centrifugal force caused by a constant-rate rotation that causes the Earth's shape and structure to become ellipsoidal. Deformations caused by external solar-system bodies are discussed in terms of deformability parameters. The next three chapters handle additional complex deviations: non-rigid Earth and more general Earth models, anelastic Earth parameters, and the effects of the fluid layers (i.e., ocean and atmosphere) on Earth rotation. Chapter 10 complements Chapter 7 with refinements that take into account diverse small effects such as the effect of a thermal conductive layer at the top of the core, Core Mantle and Inner Boundary coupling effects on nutation, electromagnetic coupling, and so-called topographic coupling. Chapter 11 covers comparison of observation and theory, and tells us that the present-date precision of the nutation theory is at the level of milliarcseconds in the time domain, and of a tenth of a microsecond in the frequency domain (with some exceptions). This chapter is followed by a 25-page chapter of definitions of equator, equinox, celestial intermediate pole and origin, stellar angle

  19. Rooted tRNAomes and evolution of the genetic code

    PubMed Central

    Pak, Daewoo; Du, Nan; Kim, Yunsoo; Sun, Yanni

    2018-01-01

    ABSTRACT We advocate for a tRNA- rather than an mRNA-centric model for evolution of the genetic code. The mechanism for evolution of cloverleaf tRNA provides a root sequence for radiation of tRNAs and suggests a simplified understanding of code evolution. To analyze code sectoring, rooted tRNAomes were compared for several archaeal and one bacterial species. Rooting of tRNAome trees reveals conserved structures, indicating how the code was shaped during evolution and suggesting a model for evolution of a LUCA tRNAome tree. We propose the polyglycine hypothesis that the initial product of the genetic code may have been short chain polyglycine to stabilize protocells. In order to describe how anticodons were allotted in evolution, the sectoring-degeneracy hypothesis is proposed. Based on sectoring, a simple stepwise model is developed, in which the code sectors from a 1→4→8→∼16 letter code. At initial stages of code evolution, we posit strong positive selection for wobble base ambiguity, supporting convergence to 4-codon sectors and ∼16 letters. In a later stage, ∼5–6 letters, including stops, were added through innovating at the anticodon wobble position. In archaea and bacteria, tRNA wobble adenine is negatively selected, shrinking the maximum size of the primordial genetic code to 48 anticodons. Because 64 codons are recognized in mRNA, tRNA-mRNA coevolution requires tRNA wobble position ambiguity leading to degeneracy of the code. PMID:29372672

  20. Theoretical studies of damage to 3'-uridine monophosphate induced by electron attachment.

    PubMed

    Zhang, Ru Bo; Zhang, Ke; Eriksson, Leif A

    2008-01-01

    Low-energy electrons (LEE) are well known to induce nucleic acid damage. However, the damage mechanisms related to charge state and structural features remain to be explored in detail. In the present work, we have investigated the N1-glycosidic and C3'-O(P) bond ruptures of 3'-UMP (UMP=uridine monophosphate) and the protonated form 3'-UMPH with -1 and zero charge, respectively, based on hybrid density functional theory (DFT) B3 LYP together with the 6-31+G(d,p) basis set. The glycosidic bond breakage reactions of the 3'UMP and 3'UMPH electron adducts are exothermic in both cases, with barrier heights of 19-20 kcal mol(-1) upon inclusion of bulk solvation. The effects of the charge state on the phosphate group are marginal, but the C2'-OH group destabilizes the transition structure of glycosidic bond rupture of 3'-UMPH in the gas phase by approximately 5.0 kcal mol(-1). This is in contrast with the C3'-O(P) bond ruptures induced by LEE in which the charge state on the phosphate influences the barrier heights and reaction energies considerably. The barrier towards C3'-O(P) bond dissociation in the 3'UMP electron adduct is higher in the gas phase than the one corresponding to glycosidic bond rupture and is dramatically influenced by the C2'-OH group and bulk salvation, which decreases the barrier to 14.7 kcal mol(-1). For the C3'-O(P) bond rupture of the 3'UMPH electron adduct, the reaction is exothermic and the barrier is even lower, 8.2 kcal mol(-1), which is in agreement with recent results for 3'-dTMPH and 5'-dTMPH (dTMPH=deoxythymidine monophosphate). Both the Mulliken atomic charges and unpaired-spin distribution play significant roles in the reactions.

  1. Tautomeric transition between wobble A·C DNA base mispair and Watson-Crick-like A·C* mismatch: microstructural mechanism and biological significance.

    PubMed

    Brovarets', Ol'ha O; Hovorun, Dmytro M

    2015-06-21

    Here, we use MP2/DFT quantum-chemical methods combined with Quantum Theory of Atoms in Molecules to study the tautomeric transition between wobble A·C(w) mismatch and Watson-Crick-like A·C*(WC) base mispair, proceeding non-dissociatively via sequential proton transfer between bases through the planar, highly stable and zwitterionic TS(A∙C-)(A∙C(W)<-->A∙C&(WC)) transition state joined by the participation of (A)N6(+)H∙∙∙N4(-)(C), (A)N1(+)H∙∙∙N4(-)(C) and (A)C2(+)H∙∙∙N3(-)(C) H-bonds. Notably, the A·C(w) ↔ A·C*(WC) tautomerization reaction is accompanied by 10 unique patterns of the specific intermolecular interactions that consistently replace each other. Our data suggest that biologically significant A·C(w) → A·C*(WC) tautomerization is a kinetically controlled pathway for formation of the enzymatically competent Watson-Crick-like A·C*(WC) DNA base mispair in the essentially hydrophobic recognition pocket of the high-fidelity DNA-polymerase, responsible for the occurrence of spontaneous point AC/CA incorporation errors during DNA biosynthesis.

  2. Milk thistle, a herbal supplement, decreases the activity of CYP3A4 and uridine diphosphoglucuronosyl transferase in human hepatocyte cultures.

    PubMed

    Venkataramanan, R; Ramachandran, V; Komoroski, B J; Zhang, S; Schiff, P L; Strom, S C

    2000-11-01

    Milk thistle extract is one of the most commonly used nontraditional therapies, particularly in Germany. Milk thistle is known to contain a number of flavonolignans. We evaluated the effect of silymarin, on the activity of various hepatic drug-metabolizing enzymes in human hepatocyte cultures. Treatment with silymarin (0.1 and 0.25 mM) significantly reduced the activity of CYP3A4 enzyme (by 50 and 100%, respectively) as determined by the formation of 6-beta-hydroxy testosterone and the activity of uridine diphosphoglucuronosyl transferase (UGT1A6/9) (by 65 and 100%, respectively) as measured by the formation of 4-methylumbelliferone glucuronide. Silymarin (0.5 mM) also significantly decreased mitochondrial respiration as determined by MTT reduction in human hepatocytes. These observations point to the potential of silymarin to impair hepatic metabolism of certain coadministered drugs in humans. Indiscriminate use of herbal products may lead to altered pharmacokinetics of certain drugs and may result in increased toxicity of certain drugs.

  3. Distinct hydroxy-radical-induced damage of 3'-uridine monophosphate in RNA: a theoretical study.

    PubMed

    Zhang, Ru bo; Eriksson, Leif A

    2009-01-01

    RNA strand scission and base release in 3'-uridine monophosphate (UMP), induced by OH radical addition to uracil, is studied at the DFT B3LYP/6-31+G(d,p) level in the gas phase and in solution. In particular, the mechanism of hydrogen-atom transfer subsequent to radical formation, from C2' on the sugar to the C6 site on the base, is explored. The barriers of (C2'-)H2'(a) abstraction by the C6 radical site range from 11.2 to 20.0 kcal mol(-1) in the gas phase and 14.1 to 21.0 kcal mol(-1) in aqueous solution, indicating that the local surrounding governs the hydrogen-abstraction reaction in a stereoselective way. The calculated N1-C1' (N1-glycosidic bond) and beta-phosphate bond strengths show that homolytic and heterolytic bond-breaking processes are largely favored in each case, respectively. The barrier for beta-phosphate bond rupture is approximately 3.2-4.0 kcal mol(-1) and is preferred by 8-12 kcal mol(-1) over N1-glycosidic bond cleavage in both the gas phase and solution. The beta-phosphate bond-rupture reactions are exothermal in the gas phase and solution, whereas N1-C1' bond-rupture reactions require both solvation and thermal corrections at 298 K to be energetically favored. The presence of the ribose 2'-OH group and its formation of low-barrier hydrogen bonds with oxygen atoms of the 3'-phosphate linkage are highly important for hydrogen transfer and the subsequent bond-breakage reactions.

  4. Deficiency of uridine monophosphate synthase (DUMPS) and X-chromosome deletion in fetal mummification in cattle.

    PubMed

    Ghanem, Mohamed Elshabrawy; Nakao, Toshihiko; Nishibori, Masahide

    2006-01-01

    Ten mummified fetuses were tested for the deficiency of uridine monophosphate synthase (DUMPS), which is known to contribute to the embryonic and fetal mortality in cattle. Genomic DNAs of the mummified fetuses were extracted from tissue samples collected from the mummies and were amplified by GenomiPhi DNA amplification kit. UMPS gene of the mummies was amplified by polymerase chain reaction (PCR) with DUMPS primers. Out of ten mummies examined, two fetuses were heterozygous (carriers) for DUMPS as indicated by the presences of three bands of 89, 53 and 36 bp. Estimated stage of gestation when the death occurred in the two mummies was 3.5 and 2.5 months, respectively. The other fetuses exhibited only two bands of 53 and 36 bp on the polyacrylamide gel indicated that they were normal. On the other hand, all the mummies were sexed using AMX/Y primers. Specific regions of Y and X chromosomes were amplified by PCR using AMX/Y. The expected 280 bp fragment in the female sample and the 280 and 217 bp in the male sample were observed. Nine mummies had a normal X and Y chromosome bands; however, the other mummified fetus exhibited only Y chromosome band, while the constitutive X chromosome fragment was missing. The estimated stage of gestation when the death occurred in this mummified fetus was 100 days. This might be the first report of DUMPS and X-chromosome deletion at the amelogenin gene in bovine-mummified fetuses in Japan.

  5. Crystal structures of the catalytic domains of pseudouridine synthases RluC and RluD from Escherichia coli.

    PubMed

    Mizutani, Kenji; Machida, Yoshitaka; Unzai, Satoru; Park, Sam-Yong; Tame, Jeremy R H

    2004-04-20

    The most frequent modification of RNA, the conversion of uridine bases to pseudouridines, is found in all living organisms and often in highly conserved locations in ribosomal and transfer RNA. RluC and RluD are homologous enzymes which each convert three specific uridine bases in Escherichia coli ribosomal 23S RNA to pseudouridine: bases 955, 2504, and 2580 in the case of RluC and 1911, 1915, and 1917 in the case of RluD. Both have an N-terminal S4 RNA binding domain. While the loss of RluC has little phenotypic effect, loss of RluD results in a much reduced growth rate. We have determined the crystal structures of the catalytic domain of RluC, and full-length RluD. The S4 domain of RluD appears to be highly flexible or unfolded and is completely invisible in the electron density map. Despite the conserved topology shared by the two proteins, the surface shape and charge distribution are very different. The models suggest significant differences in substrate binding by different pseudouridine synthases.

  6. Protein degradation and dynamic tRNA thiolation fine-tune translation at elevated temperatures.

    PubMed

    Tyagi, Kshitiz; Pedrioli, Patrick G A

    2015-05-19

    Maintenance of protein quality control has implications in various processes such as neurodegeneration and ageing. To investigate how environmental insults affect this process, we analysed the proteome of yeast continuously exposed to mild heat stress. In agreement with previous transcriptomics studies, amongst the most marked changes, we found up-regulation of cytoprotective factors; a shift from oxidative phosphorylation to fermentation; and down-regulation of translation. Importantly, we also identified a novel, post-translationally controlled, component of the heat shock response. The abundance of Ncs2p and Ncs6p, two members of the URM1 pathway responsible for the thiolation of wobble uridines in cytoplasmic tRNAs tK(UUU), tQ(UUG) and tE(UUC), is down-regulated in a proteasomal dependent fashion. Using random forests we show that this results in differential translation of transcripts with a biased content for the corresponding codons. We propose that the role of this pathway in promoting catabolic and inhibiting anabolic processes, affords cells with additional time and resources needed to attain proper protein folding under periods of stress. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  7. Photoelectron spectroscopic study of the hydrated nucleoside anions: Uridine(-)(H(2)O)(n=0-2), cytidine(-)(H(2)O)(n=0-2), and thymidine(-)(H(2)O)(n=0,1).

    PubMed

    Li, Xiang; Wang, Haopeng; Bowen, Kit H

    2010-10-14

    The hydrated nucleoside anions, uridine(-)(H(2)O)(n=0-2), cytidine(-)(H(2)O)(n=0-2), and thymidine(-)(H(2)O)(n=0,1), have been prepared in beams and studied by anion photoelectron spectroscopy in order to investigate the effects of a microhydrated environment on parent nucleoside anions. Vertical detachment energies (VDEs) were measured for all eight anions, and from these, estimates were made for five sequential anion hydration energies. Excellent agreement was found between our measured VDE value for thymidine(-)(H(2)O)(1) and its calculated value in the companion article by S. Kim and H. F. Schaefer III.

  8. Photoelectron spectroscopic study of the hydrated nucleoside anions: Uridine-(H2O)n=0-2, cytidine-(H2O)n=0-2, and thymidine-(H2O)n=0,1

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Wang, Haopeng; Bowen, Kit H.

    2010-10-01

    The hydrated nucleoside anions, uridine-(H2O)n=0-2, cytidine-(H2O)n=0-2, and thymidine-(H2O)n=0,1, have been prepared in beams and studied by anion photoelectron spectroscopy in order to investigate the effects of a microhydrated environment on parent nucleoside anions. Vertical detachment energies (VDEs) were measured for all eight anions, and from these, estimates were made for five sequential anion hydration energies. Excellent agreement was found between our measured VDE value for thymidine-(H2O)1 and its calculated value in the companion article by S. Kim and H. F. Schaefer III.

  9. Production of uridine 5'-monophosphate by Corynebacterium ammoniagenes ATCC 6872 using a statistically improved biocatalytic process.

    PubMed

    Wang, Xing; Wang, Xiuwen; Yin, Mengxin; Xiao, Zijun; Ma, Cuiqing; Lin, Zhixin; Wang, Peng George; Xu, Ping

    2007-08-01

    Attempts were made with success to develop a two-step biocatalytic process for uridine 5'-monophosphate (UMP) production from orotic acid by Corynebacterium ammoniagenes ATCC 6872: the strain was first cultivated in a high salt mineral medium, and then cells were harvested and used as the catalyst in the UMP production reaction. Effects of cultivation and reaction conditions on UMP production were investigated. The cells exhibited the highest biocatalytic ability when cultivated in a medium containing corn steep liquor at pH 7.0 for 15 h in the exponential phase of growth. To optimize the reaction, both "one-factor-at-a-time" method and statistical method were performed. By "one-factor-at-a-time" optimization, orotic acid, glucose, phosphate ion (equimolar KH(2)PO(4) and K(2)HPO(4)), MgCl(2), Triton X-100 were shown to be the optimum components for the biocatalytic reaction. Phosphate ion and C. ammoniagenes cell were furthermore demonstrated as the most important main effects on UMP production by Plackett-Burman design, indicating that 5-phosphoribosyl-1-pyrophosphate (PRPP) synthesis was the rate-limiting step for pyrimidine nucleotides production. Optimization by a central composition design (CCD) was then performed, and up to 32 mM (10.4 g l(-1)) UMP was accumulated in 24 h from 38.5 mM (6 g l(-1)) orotic acid. The yield was threefold higher than the original UMP yield before optimization.

  10. Novel mRNA isoforms and mutations of uridine monophosphate synthetase and 5-fluorouracil resistance in colorectal cancer.

    PubMed

    Griffith, M; Mwenifumbo, J C; Cheung, P Y; Paul, J E; Pugh, T J; Tang, M J; Chittaranjan, S; Morin, R D; Asano, J K; Ally, A A; Miao, L; Lee, A; Chan, S Y; Taylor, G; Severson, T; Hou, Y-C; Griffith, O L; Cheng, G S W; Novik, K; Moore, R; Luk, M; Owen, D; Brown, C J; Morin, G B; Gill, S; Tai, I T; Marra, M A

    2013-04-01

    The drug fluorouracil (5-FU) is a widely used antimetabolite chemotherapy in the treatment of colorectal cancer. The gene uridine monophosphate synthetase (UMPS) is thought to be primarily responsible for conversion of 5-FU to active anticancer metabolites in tumor cells. Mutation or aberrant expression of UMPS may contribute to 5-FU resistance during treatment. We undertook a characterization of UMPS mRNA isoform expression and sequence variation in 5-FU-resistant cell lines and drug-naive or -exposed primary and metastatic tumors. We observed reciprocal differential expression of two UMPS isoforms in a colorectal cancer cell line with acquired 5-FU resistance relative to the 5-FU-sensitive cell line from which it was derived. A novel isoform arising as a consequence of exon skipping was increased in abundance in resistant cells. The underlying mechanism responsible for this shift in isoform expression was determined to be a heterozygous splice site mutation acquired in the resistant cell line. We developed sequencing and expression assays to specifically detect alternative UMPS isoforms and used these to determine that UMPS was recurrently disrupted by mutations and aberrant splicing in additional 5-FU-resistant colorectal cancer cell lines and colorectal tumors. The observed mutations, aberrant splicing and downregulation of UMPS represent novel mechanisms for acquired 5-FU resistance in colorectal cancer.

  11. Optical activity and electronic absorption spectra of some simple nucleosides related to cytidine and uridine: all-valence-shell molecular orbital calculations.

    PubMed Central

    Miles, D W; Redington, P K; Miles, D L; Eyring, H

    1981-01-01

    The circular dichroism and electronic absorption of three simple model systems for cytidine and uridine have been measured to 190 nm. The molecular spectral properties (excitation wavelengths, oscillator strengths, rotational strengths, and polarization directions) and electronic transitional patterns were investigated by using wave functions of the entire nucleoside with the goal of establishing the reliability of the theoretical method. The computed electronic absorption quantities were shown to be in satisfactory agreement with experimental data. It was found that the computed optical rotatory strengths of the B2u and E1u electronic transitions and lowest observed n-pi transition are in good agreement with experimental values. Electronic transitions were characterized by their electronic transitional patterns derived from population analysis of the transition density matrix. The theoretical rotational strengths associated with the B2u and E1u transitions stabilize after the use of just a few singly excited configurations in the configuration interaction basis and, hypothetically, are more reliable as indicators of conformation in pyrimidine nucleosides related to cytidine. PMID:6950393

  12. Physico-chemical profiles of the wobble ↔ Watson-Crick G*·2AP(w) ↔ G·2AP(WC) and A·2AP(w) ↔ A*·2AP(WC) tautomerisations: a QM/QTAIM comprehensive survey.

    PubMed

    Brovarets', Ol'ha O; Voiteshenko, Ivan S; Hovorun, Dmytro M

    2017-12-20

    This study is intended to clarify in detail the tautomeric transformations of the wobble (w) G*·2AP(w) and A·2AP(w) nucleobase mispairs involving 2-aminopurine (2AP) into the Watson-Crick (WC) G·2AP(WC) and A*·2AP(WC) base mispairs (asterisks denote mutagenic tautomers of the DNA bases), respectively, by quantum-mechanical methods and Bader's Quantum Theory of Atoms in Molecules. Our previously reported methodology has been used, which allows the evolution of the physico-chemical parameters to be tracked along the entire internal reaction coordinate (IRC), not exclusively in the stationary states of these reactions. These biologically important G*·2AP(w) ↔ G·2AP(WC) and A·2AP(w) ↔ A*·2AP(WC) w ↔ WC tautomerisations, which are involved in mutagenic tautomerically-conformational pathways, determine the origin of the transitions and transversions induced by 2AP. In addition, it is established that they proceed through planar, highly stable, zwitterionic transition states and they exhibit similar physico-chemical profiles and stages of sequential intrapair proton transfer, followed by spatial rearrangement of the nucleobases relative to each other within the base pairs. These w ↔ WC tautomerisations occur non-dissociatively and are accompanied by a significant alteration in geometry (from wobble to Watson-Crick and vice versa) and redistribution of the specific intermolecular interactions, which can be divided into 10 patterns including AHB H-bonds and loosened A-H-B covalent bridges along the IRC of tautomerisation. Based on the redistribution of the geometrical and electron-topological parameters of the intrapair hydrogen bonds, exactly 9 key points have been allocated to characterize the evolution of these reactions.

  13. Crystal structure and RNA-binding properties of an Hfq homolog from the deep-branching Aquificae: conservation of the lateral RNA-binding mode

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stanek, Kimberly A.; Patterson-West, Jennifer; Randolph, Peter S.

    The host factor Hfq, as the bacterial branch of the Sm family, is an RNA-binding protein involved in the post-transcriptional regulation of mRNA expression and turnover. Hfq facilitates pairing between small regulatory RNAs (sRNAs) and their corresponding mRNA targets by binding both RNAs and bringing them into close proximity. Hfq homologs self-assemble into homo-hexameric rings with at least two distinct surfaces that bind RNA. Recently, another binding site, dubbed the `lateral rim', has been implicated in sRNA·mRNA annealing; the RNA-binding properties of this site appear to be rather subtle, and its degree of evolutionary conservation is unknown. An Hfq homologmore » has been identified in the phylogenetically deep-branching thermophileAquifex aeolicus(Aae), but little is known about the structure and function of Hfq from basal bacterial lineages such as the Aquificae. Therefore,AaeHfq was cloned, overexpressed, purified, crystallized and biochemically characterized. Structures ofAaeHfq were determined in space groupsP1 andP6, both to 1.5 Å resolution, and nanomolar-scale binding affinities for uridine- and adenosine-rich RNAs were discovered. Co-crystallization with U 6RNA reveals that the outer rim of theAaeHfq hexamer features a well defined binding pocket that is selective for uracil. ThisAaeHfq structure, combined with biochemical and biophysical characterization of the homolog, reveals deep evolutionary conservation of the lateral RNA-binding mode, and lays a foundation for further studies of Hfq-associated RNA biology in ancient bacterial phyla.« less

  14. Role of the uridine/cytidine kinase 2 mutation in cellular sensitiveness toward 3'-ethynylcytidine treatment of human cancer cells.

    PubMed

    Sato, Akira; Takano, Takeshi; Hiramoto, Akiko; Naito, Tomoharu; Matsuda, Akira; Fukushima, Masakazu; Wataya, Yusuke; Kim, Hye-Sook

    2017-08-01

    A nucleosidic medicine, 1-(3-C-ethynyl-β-D-ribo-pentofuranosyl)cytosine [3'-ethynylcytidine (ECyd)], is a potent inhibitor of RNA polymerase I and shows anticancer activity to various human solid tumors in vitro and in vivo. ECyd is phosphorylated to 3'-ethyntlcytidine 5'-monophosphate by uridine/cytidine kinase 2 (UCK2) and subsequently further to diphosphate and triphosphate (3'-ethyntlcytidine 5'-diphosphate, 3'-ethyntlcytidine 5'-triphosphate). 3'-Ethyntlcytidine 5'-triphosphate is an active metabolite that can inhibit RNA polymerase I competitively, causing cancer cell death. Here, to identify the UCK2 mutation for detecting responder or nonresponder to ECyd, we investigated the relationship between point mutation of the UCK2 gene and response to ECyd in various human solid tumors. We identified several functional point mutations including the splice-site mutation of the UCK2 gene IVS5+5 G>A. In addition, we found that the IVS5+5 G>A variant generates an aberrant mRNA transcript, namely, truncated mRNA was produced and normal mRNA levels were markedly decreased in the ECyd-resistant cancer cell line HT1080. We concluded that these findings strongly suggest that the IVS5+5 G>A variant would affect the expression level of the UCK2 transcript, resulting in decreased sensitivity to ECyd.

  15. A double-blind, randomized, comparative study of the use of a combination of uridine triphosphate trisodium, cytidine monophosphate disodium, and hydroxocobalamin, versus isolated treatment with hydroxocobalamin, in patients presenting with compressive neuralgias.

    PubMed

    Goldberg, Henrique; Mibielli, Marco Antonio; Nunes, Carlos Pereira; Goldberg, Stephanie Wrobel; Buchman, Luiz; Mezitis, Spyros Ge; Rzetelna, Helio; Oliveira, Lisa; Geller, Mauro; Wajnsztajn, Fernanda

    2017-01-01

    This paper reports on the results of treatment of compressive neuralgia using a combination of nucleotides (uridine triphosphate trisodium [UTP] and cytidine monophosphate disodium [CMP]) and vitamin B 12 . To assess the safety and efficacy of the combination of nucleotides (UTP and CMP) and vitamin B 12 in patients presenting with neuralgia arising from neural compression associated with degenerative orthopedic alterations and trauma, and to compare these effects with isolated administration of vitamin B 12 . A randomized, double-blind, controlled trial, consisting of a 30-day oral treatment period: Group A (n=200) receiving nucleotides + vitamin B 12, and Group B (n=200) receiving vitamin B 12 alone. The primary study endpoint was the percentage of subjects presenting pain visual analog scale (VAS) scores ≤20 at end of study treatment period. Secondary study endpoints included the percentage of subjects presenting improvement ≥5 points on the patient functionality questionnaire (PFQ); percentage of subjects presenting pain reduction (reduction in VAS scores at study end in relation to pretreatment); and number of subjects presenting adverse events. The results of this study showed a more expressive improvement in efficacy evaluations among subjects treated with the combination of nucleotides + vitamin B 12 , with a statistically significant superiority of the combination in pain reduction (evidenced by VAS scores). There were adverse events in both treatment groups, but these were transitory and no severe adverse event was recorded during the study period. Safety parameters were maintained throughout the study in both treatment groups. The combination of uridine, cytidine, and vitamin B 12 was safe and effective in the treatment of neuralgias arising from neural compression associated with degenerative orthopedic alterations and trauma.

  16. Effect of BrU on the transition between wobble Gua-Thy and tautomeric Gua-Thy base-pairs: ab initio molecular orbital calculations

    NASA Astrophysics Data System (ADS)

    Nomura, Kazuya; Hoshino, Ryota; Hoshiba, Yasuhiro; Danilov, Victor I.; Kurita, Noriyuki

    2013-04-01

    We investigated transition states (TS) between wobble Guanine-Thymine (wG-T) and tautomeric G-T base-pair as well as Br-containing base-pairs by MP2 and density functional theory (DFT) calculations. The obtained TS between wG-T and G*-T (asterisk is an enol-form of base) is different from TS got by the previous DFT calculation. The activation energy (17.9 kcal/mol) evaluated by our calculation is significantly smaller than that (39.21 kcal/mol) obtained by the previous calculation, indicating that our TS is more preferable. In contrast, the obtained TS and activation energy between wG-T and G-T* are similar to those obtained by the previous DFT calculation. We furthermore found that the activation energy between wG-BrU and tautomeric G-BrU is smaller than that between wG-T and tautomeric G-T. This result elucidates that the replacement of CH3 group of T by Br increases the probability of the transition reaction producing the enol-form G* and T* bases. Because G* prefers to bind to T rather than to C, and T* to G not A, our calculated results reveal that the spontaneous mutation from C to T or from A to G base is accelerated by the introduction of wG-BrU base-pair.

  17. The initial uridine of primary piRNAs does not create the tenth adenine that Is the hallmark of secondary piRNAs.

    PubMed

    Wang, Wei; Yoshikawa, Mayu; Han, Bo W; Izumi, Natsuko; Tomari, Yukihide; Weng, Zhiping; Zamore, Phillip D

    2014-12-04

    PIWI-interacting RNAs (piRNAs) silence transposons in animal germ cells. PIWI proteins bind and amplify piRNAs via the "Ping-Pong" pathway. Because PIWI proteins cleave RNAs between target nucleotides t10 and t11-the nucleotides paired to piRNA guide positions g10 and g11-the first ten nucleotides of piRNAs participating in the Ping-Pong amplification cycle are complementary. Drosophila piRNAs bound to the PIWI protein Aubergine typically begin with uridine (1U), while piRNAs bound to Argonaute3, which are produced by Ping-Pong amplification, often have adenine at position 10 (10A). The Ping-Pong model proposes that the 10A is a consequence of 1U. We find that 10A is not caused by 1U. Instead, fly Aubergine as well as its homologs, Siwi in silkmoth and MILI in mice, have an intrinsic preference for adenine at the t1 position of their target RNAs; during Ping-Pong amplification, this t1A subsequently becomes the g10A of a piRNA bound to Argonaute3. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Uridine 5′-Triphosphate Promotes In Vitro Schwannoma Cell Migration through Matrix Metalloproteinase-2 Activation

    PubMed Central

    Martiañez, Tania; Segura, Mònica; Figueiro-Silva, Joana; Grijota-Martinez, Carmen; Trullas, Ramón; Casals, Núria

    2014-01-01

    In response to peripheral nerve injury, Schwann cells adopt a migratory phenotype and modify the extracellular matrix to make it permissive for cell migration and axonal re-growth. Uridine 5′-triphosphate (UTP) and other nucleotides are released during nerve injury and activate purinergic receptors expressed on the Schwann cell surface, but little is known about the involvement of purine signalling in wound healing. We studied the effect of UTP on Schwannoma cell migration and wound closure and the intracellular signaling pathways involved. We found that UTP treatment induced Schwannoma cell migration through activation of P2Y2 receptors and through the increase of extracellular matrix metalloproteinase-2 (MMP-2) activation and expression. Knockdown P2Y2 receptor or MMP-2 expression greatly reduced wound closure and MMP-2 activation induced by UTP. MMP-2 activation evoked by injury or UTP was also mediated by phosphorylation of all 3 major mitogen-activated protein kinases (MAPKs): JNK, ERK1/2, and p38. Inhibition of these MAPK pathways decreased both MMP-2 activation and cell migration. Interestingly, MAPK phosphorylation evoked by UTP exhibited a biphasic pattern, with an early transient phosphorylation 5 min after treatment, and a late and sustained phosphorylation that appeared at 6 h and lasted up to 24 h. Inhibition of MMP-2 activity selectively blocked the late, but not the transient, phase of MAPK activation. These results suggest that MMP-2 activation and late MAPK phosphorylation are part of a positive feedback mechanism to maintain the migratory phenotype for wound healing. In conclusion, our findings show that treatment with UTP stimulates in vitro Schwannoma cell migration and wound repair through a MMP-2-dependent mechanism via P2Y2 receptors and MAPK pathway activation. PMID:24905332

  19. Molecular dynamics and crystallization phenomenon of supercooled and glassy DNA and RNA nucleosides: β-adenosine, β-thymidine, and β-uridine

    NASA Astrophysics Data System (ADS)

    Adrjanowicz, K.; Wojnarowska, Z.; Grzybowska, K.; Hawelek, L.; Kaminski, K.; Paluch, M.; Kasprzycka, A.; Walczak, K.

    2011-11-01

    Nucleosides are chemical compounds that have an extremely important biological role; they can be found in all types of living organisms. They are crucial components from which DNA and RNA acids are built. In addition, nucleosides are key regulators of many physiological processes. In this paper, the molecular dynamics in the liquid and glassy state of three selected nucleosides, β-adenosine, β-thymidine, and β-uridine, was investigated by means of dielectric spectroscopy. Our results revealed multiple relaxation processes associated with different types of molecular motions. Besides the primary α relaxation, two secondary modes in the glassy states of examined compounds were identified. Crystallization progress monitored by dielectric spectroscopy and x-ray diffraction technique at isostructural relaxation conditions revealed that the examined nucleosides possess completely different tendencies to recrystallize from the liquid as well as the glassy state. We have also made an attempt to predict the time scale of molecular motion below the glass transition temperatures of the respective nucleosides to discuss their potential stability at room temperature over prolonged storage time. Finally, combination of molecular mobility studies with evaluation of thermodynamic parameters from calorimetric measurements allowed us to discuss the fundamental roles of both kinetic and thermodynamic factors in governing the physical stability of the glassy state.

  20. Conservation businesses and conservation planning in a biological diversity hotspot.

    PubMed

    Di Minin, Enrico; Macmillan, Douglas Craig; Goodman, Peter Styan; Escott, Boyd; Slotow, Rob; Moilanen, Atte

    2013-08-01

    The allocation of land to biological diversity conservation competes with other land uses and the needs of society for development, food, and extraction of natural resources. Trade-offs between biological diversity conservation and alternative land uses are unavoidable, given the realities of limited conservation resources and the competing demands of society. We developed a conservation-planning assessment for the South African province of KwaZulu-Natal, which forms the central component of the Maputaland-Pondoland-Albany biological diversity hotspot. Our objective was to enhance biological diversity protection while promoting sustainable development and providing spatial guidance in the resolution of potential policy conflicts over priority areas for conservation at risk of transformation. The conservation-planning assessment combined spatial-distribution models for 646 conservation features, spatial economic-return models for 28 alternative land uses, and spatial maps for 4 threats. Nature-based tourism businesses were competitive with other land uses and could provide revenues of >US$60 million/year to local stakeholders and simultaneously help meeting conservation goals for almost half the conservation features in the planning region. Accounting for opportunity costs substantially decreased conflicts between biological diversity, agricultural use, commercial forestry, and mining. Accounting for economic benefits arising from conservation and reducing potential policy conflicts with alternative plans for development can provide opportunities for successful strategies that combine conservation and sustainable development and facilitate conservation action. © 2013 Society for Conservation Biology.

  1. Direct evidence for tautomerization of the uracil moiety within the Pb2+/uridine-5'-monophosphate complex: a combined tandem mass spectrometry and IRMPD study.

    PubMed

    Salpin, Jean-Yves; Guillaumont, Sébastien; Ortiz, Daniel; Tortajada, Jeanine; Maître, Philippe

    2011-08-15

    The structure of the [Pb(UMP)-H](+) (UMP = uridine-5'-monophosphate) complex was studied in the gas phase by combining electrospray ionization (ESI), tandem mass spectrometry, and mid-infrared multiple photon dissociation (IRMPD) spectroscopy. The results obtained show that Pb(2+) ions interact not only with the deprotonated phosphate group but also with a carbonyl group of the nucleobase moiety by folding of the mononucleotide, resulting in macrochelates that are not likely to be present in solution. Comparison between the IRMPD and DFT-computed spectra suggests that the ESI-generated complex likely corresponds to a mixture of several structures, and establishes the enolic tautomers as the most abundant species for the [Pb(UMP)-H](+) ion, while the very weak IRMPD signal observed at ∼1763 cm(-1) points to a minor population of oxo forms. Our data also suggest that losing the nucleobase residue under CID conditions does not necessarily mean a lack of interaction between the metal and the nucleobase moiety, as commonly reported in the literature for large oligonucleotides. © 2011 American Chemical Society

  2. 5-(Perylen-3-yl)Ethynyl-arabino-Uridine (aUY11), an Arabino-Based Rigid Amphipathic Fusion Inhibitor, Targets Virion Envelope Lipids To Inhibit Fusion of Influenza Virus, Hepatitis C Virus, and Other Enveloped Viruses

    PubMed Central

    Colpitts, Che C.; Ustinov, Alexey V.; Epand, Raquel F.; Epand, Richard M.; Korshun, Vladimir A.

    2013-01-01

    Entry of enveloped viruses requires fusion of viral and cellular membranes. Fusion requires the formation of an intermediate stalk structure, in which only the outer leaflets are fused. The stalk structure, in turn, requires the lipid bilayer of the envelope to bend into negative curvature. This process is inhibited by enrichment in the outer leaflet of lipids with larger polar headgroups, which favor positive curvature. Accordingly, phospholipids with such shape inhibit viral fusion. We previously identified a compound, 5-(perylen-3-yl)ethynyl-2′-deoxy-uridine (dUY11), with overall shape and amphipathicity similar to those of these phospholipids. dUY11 inhibited the formation of the negative curvature necessary for stalk formation and the fusion of a model enveloped virus, vesicular stomatitis virus (VSV). We proposed that dUY11 acted by biophysical mechanisms as a result of its shape and amphipathicity. To test this model, we have now characterized the mechanisms against influenza virus and HCV of 5-(perylen-3-yl)ethynyl-arabino-uridine (aUY11), which has shape and amphipathicity similar to those of dUY11 but contains an arabino-nucleoside. aUY11 interacted with envelope lipids to inhibit the infectivity of influenza virus, hepatitis C virus (HCV), herpes simplex virus 1 and 2 (HSV-1/2), and other enveloped viruses. It specifically inhibited the fusion of influenza virus, HCV, VSV, and even protein-free liposomes to cells. Furthermore, aUY11 inhibited the formation of negative curvature in model lipid bilayers. In summary, the arabino-derived aUY11 and the deoxy-derived dUY11 act by the same antiviral mechanisms against several enveloped but otherwise unrelated viruses. Therefore, chemically unrelated compounds of appropriate shape and amphipathicity target virion envelope lipids to inhibit formation of the negative curvature required for fusion, inhibiting infectivity by biophysical, not biochemical, mechanisms. PMID:23283943

  3. Oligomerization of uridine phosphorimidazolides on montmorillonite: a model for the prebiotic synthesis of RNA on minerals

    NASA Technical Reports Server (NTRS)

    Ding, P. Z.; Kawamura, K.; Ferris, J. P.

    1996-01-01

    The 5'-phosphorimidazolide of uridine reacts on Na(+)-montmorillonite 22A in aqueous solution to give oligomers as long as 7 mers. The maximum chain length increases to 9 mers and the overall oligomer yield increases when 9:1 ImpU, A5' ppA mixtures react under the same conditions. The oligomer yield and maximum chain length decreases with the structure of the added pyrophosphate in the order A5' ppA > A5' ppU > U5' ppU. Structure analysis of individual oligomer fractions was performed by selective enzymatic hydrolyses followed by HPLC analysis of the products. The regioselectivity for 3',5'-bond formation is 80-90% in the 9:1 ImpU, A5' ppA reaction, a percentage comparable to that observed in the 9:1 ImpA, A5' ppA reaction. Oligomerization of ImpU is inhibited by addition of dA5' ppdA, and MeppA. No oligomers containing A5' ppU were products of the 9:1 ImpU,A5' ppA reaction, a finding consistent with the simple addition of the ImpU to the A5' ppA and not the rearrangement of an ImpU-A5' ppA adduct. Concentrations of lysine or arginine which were close to that of the ImpU did not inhibit oligomer formation. Treatment of Na(+)-montmorillonite with 1 M arginine yielded arginine-montmorillonite, an amino acid-mineral adduct which did not catalyze ImpU oligomerization. Neither the 4-9 mers formed in the 9:1 ImpU, A5' ppA reaction nor the 4-9 mers formed by the base hydrolysis of poly(U) served as templates for the formation of oligo(A)s.

  4. Collections Conservation.

    ERIC Educational Resources Information Center

    DeCandido, Robert

    Collections conservation is an approach to the preservation treatment of books and book-like materials that is conceptualized and organized in terms of large groups of materials. This guide is intended to enable a library to evaluate its current collections conservation activities. The introduction describes collections conservation and gives…

  5. How U38, 39, and 40 of many tRNAs become the targets for pseudouridylation by TruA.

    PubMed

    Hur, Sun; Stroud, Robert M

    2007-04-27

    Translational accuracy and efficiency depend upon modification of uridines in the tRNA anticodon stem loop (ASL) by a highly conserved pseudouridine synthase TruA. TruA specifically modifies uridines at positions 38, 39, and/or 40 of tRNAs with highly divergent sequences and structures through a poorly characterized mechanism that differs from previously studied RNA-modifying enzymes. The molecular basis for the site and substrate "promiscuity" was studied by determining the crystal structures of E. coli TruA in complex with two different leucyl tRNAs in conjunction with functional assays and computer simulation. The structures capture three stages of the TruA*tRNA reaction, revealing the mechanism by which TruA selects the target site. We propose that TruA utilizes the intrinsic flexibility of the ASL for site promiscuity and also to select against intrinsically stable tRNAs to avoid their overstabilization through pseudouridylation, thereby maintaining the balance between the flexibility and stability required for its biological function.

  6. Conservation and Education in Murchison Falls Conservation Area, Uganda

    ERIC Educational Resources Information Center

    Jordahl, Mark D.

    2005-01-01

    This thesis forms the foundation for a conservation education training manual to help guides in Murchison Falls National Park, Uganda, communicate to foreign visitors about conservation issues. For background information I used a combination of text-based research and interviews to examine the application of community conservation and…

  7. A case study of assigning conservation value to dispersed habitat units for conservation planning

    USGS Publications Warehouse

    Rohweder, Jason J.; Sara C. Vacek,; Crimmins, Shawn M.; Thogmartin, Wayne E.

    2015-01-01

    Resource managers are increasingly tasked with developing habitat conservation plans in the face of numerous, sometimes competing, objectives. These plans must often be implemented across dispersed habitat conservation units that may contribute unequally to overall conservation objectives. Using U.S. Fish and Wildlife Service waterfowl production areas (WPA) in western Minnesota as our conservation landscape, we develop a landscape-scale approach for evaluating the conservation value of dispersed habitat conservation units with multiple conservation priorities. We evaluated conservation value based on a suite of variables directly applicable to conservation management practices, thus providing a direct link between conservation actions and outcomes. We developed spatial models specific to each of these conservation objectives and also developed two freely available prioritization tools to implement these analyses. We found that some WPAs provided high conservation value across a range of conservation objectives, suggesting that managing these specific areas would achieve multiple conservation goals. Conversely, other WPAs provided low conservation value for some objectives, suggesting they would be most effectively managed for a distinct set of specific conservation goals. Approaches such as ours provide a direct means of assessing the conservation value of dispersed habitat conservation units and could be useful in the development of habitat management plans, particularly when faced with multiple conservation objectives.

  8. Conservation.

    ERIC Educational Resources Information Center

    National Audubon Society, New York, NY.

    This set of teaching aids consists of seven Audubon Nature Bulletins, providing the teacher and student with informational reading on various topics in conservation. The bulletins have these titles: Plants as Makers of Soil, Water Pollution Control, The Ground Water Table, Conservation--To Keep This Earth Habitable, Our Threatened Air Supply,…

  9. Setting conservation priorities.

    PubMed

    Wilson, Kerrie A; Carwardine, Josie; Possingham, Hugh P

    2009-04-01

    A generic framework for setting conservation priorities based on the principles of classic decision theory is provided. This framework encapsulates the key elements of any problem, including the objective, the constraints, and knowledge of the system. Within the context of this framework the broad array of approaches for setting conservation priorities are reviewed. While some approaches prioritize assets or locations for conservation investment, it is concluded here that prioritization is incomplete without consideration of the conservation actions required to conserve the assets at particular locations. The challenges associated with prioritizing investments through time in the face of threats (and also spatially and temporally heterogeneous costs) can be aided by proper problem definition. Using the authors' general framework for setting conservation priorities, multiple criteria can be rationally integrated and where, how, and when to invest conservation resources can be scheduled. Trade-offs are unavoidable in priority setting when there are multiple considerations, and budgets are almost always finite. The authors discuss how trade-offs, risks, uncertainty, feedbacks, and learning can be explicitly evaluated within their generic framework for setting conservation priorities. Finally, they suggest ways that current priority-setting approaches may be improved.

  10. Orotidine Monophosphate Decarboxylase--A Fascinating Workhorse Enzyme with Therapeutic Potential.

    PubMed

    Fujihashi, Masahiro; Mnpotra, Jagjeet S; Mishra, Ram Kumar; Pai, Emil F; Kotra, Lakshmi P

    2015-05-20

    Orotidine 5'-monophosphate decarboxylase (ODCase) is known as one of the most proficient enzymes. The enzyme catalyzes the last reaction step of the de novo pyrimidine biosynthesis, the conversion from orotidine 5'-monophosphate (OMP) to uridine 5'-monophosphate. The enzyme is found in all three domains of life, Bacteria, Eukarya and Archaea. Multiple sequence alignment of 750 putative ODCase sequences resulted in five distinct groups. While the universally conserved DxKxxDx motif is present in all the groups, depending on the groups, several characteristic motifs and residues can be identified. Over 200 crystal structures of ODCases have been determined so far. The structures, together with biochemical assays and computational studies, elucidated that ODCase utilized both transition state stabilization and substrate distortion to accelerate the decarboxylation of its natural substrate. Stabilization of the vinyl anion intermediate by a conserved lysine residue at the catalytic site is considered the largest contributing factor to catalysis, while bending of the carboxyl group from the plane of the aromatic pyrimidine ring of OMP accounts for substrate distortion. A number of crystal structures of ODCases complexed with potential drug candidate molecules have also been determined, including with 6-iodo-uridine, a potential antimalarial agent. Copyright © 2015 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

  11. Conservation laws and conserved quantities for (1+1)D linearized Boussinesq equations

    NASA Astrophysics Data System (ADS)

    Carvalho, Cindy; Harley, Charis

    2017-05-01

    Conservation laws and physical conserved quantities for the (1+1)D linearized Boussinesq equations at a constant water depth are presented. These equations describe incompressible, inviscid, irrotational fluid flow in the form of a non steady solitary wave. A systematic multiplier approach is used to obtain the conservation laws of the system of third order partial differential equations (PDEs) in dimensional form. Physical conserved quantities are derived by integrating the conservation laws in the direction of wave propagation and imposing decaying boundary conditions in the horizontal direction. One of these is a newly discovered conserved quantity which relates to an energy flux density.

  12. Building robust conservation plans.

    PubMed

    Visconti, Piero; Joppa, Lucas

    2015-04-01

    Systematic conservation planning optimizes trade-offs between biodiversity conservation and human activities by accounting for socioeconomic costs while aiming to achieve prescribed conservation objectives. However, the most cost-efficient conservation plan can be very dissimilar to any other plan achieving the set of conservation objectives. This is problematic under conditions of implementation uncertainty (e.g., if all or part of the plan becomes unattainable). We determined through simulations of parallel implementation of conservation plans and habitat loss the conditions under which optimal plans have limited chances of implementation and where implementation attempts would fail to meet objectives. We then devised a new, flexible method for identifying conservation priorities and scheduling conservation actions. This method entails generating a number of alternative plans, calculating the similarity in site composition among all plans, and selecting the plan with the highest density of neighboring plans in similarity space. We compared our method with the classic method that maximizes cost efficiency with synthetic and real data sets. When implementation was uncertain--a common reality--our method provided higher likelihood of achieving conservation targets. We found that χ, a measure of the shortfall in objectives achieved by a conservation plan if the plan could not be implemented entirely, was the main factor determining the relative performance of a flexibility enhanced approach to conservation prioritization. Our findings should help planning authorities prioritize conservation efforts in the face of uncertainty about future condition and availability of sites. © 2014 Society for Conservation Biology.

  13. 75 FR 1651 - Multistate Conservation Grant Program; Priority List for Conservation Projects

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-12

    ...-Johnson Sport Fish Restoration Act (16 U.S.C. 777 et seq.) and established the Multistate Conservation...; 91400-9410-0000-7B] Multistate Conservation Grant Program; Priority List for Conservation Projects... of wildlife and sport fish conservation projects from the Association of Fish and Wildlife Agencies...

  14. Conservation Action Handbook.

    ERIC Educational Resources Information Center

    National Rifle Association, Washington, DC.

    Conservation problems are identified, with some suggestions for action. General areas covered are: Wildlife Conservation, Soil Conservation, Clean Water, Air Pollution Action, and Outdoor Recreation Action. Appendices list private organizations or agencies concerned with natural resource use and/or management, congressional committees considering…

  15. Autoregressive harmonic analysis of the earth's polar motion using homogeneous International Latitude Service data

    NASA Technical Reports Server (NTRS)

    Chao, B. F.

    1983-01-01

    The homogeneous set of 80-year-long (1900-1979) International Latitude Service (ILS) polar motion data is analyzed using the autoregressive method (Chao and Gilbert, 1980), which resolves and produces estimates for the complex frequency (or frequency and Q) and complex amplitude (or amplitude and phase) of each harmonic component in the data. The ILS data support the multiple-component hypothesis of the Chandler wobble. It is found that the Chandler wobble can be adequately modeled as a linear combination of four (coherent) harmonic components, each of which represents a steady, nearly circular, prograde motion. The four-component Chandler wobble model 'explains' the apparent phase reversal during 1920-1940 and the pre-1950 empirical period-amplitude relation. The annual wobble is shown to be rather stationary over the years both in amplitude and in phase, and no evidence is found to support the large variations reported by earlier investigations. The Markowitz wobble is found to be marginally retrograde and appears to have a complicated behavior which cannot be resolved because of the shortness of the data set.

  16. Autoregressive harmonic analysis of the earth's polar motion using homogeneous International Latitude Service data

    NASA Astrophysics Data System (ADS)

    Chao, B. F.

    1983-12-01

    The homogeneous set of 80-year-long (1900-1979) International Latitude Service (ILS) polar motion data is analyzed using the autoregressive method (Chao and Gilbert, 1980), which resolves and produces estimates for the complex frequency (or frequency and Q) and complex amplitude (or amplitude and phase) of each harmonic component in the data. The ILS data support the multiple-component hypothesis of the Chandler wobble. It is found that the Chandler wobble can be adequately modeled as a linear combination of four (coherent) harmonic components, each of which represents a steady, nearly circular, prograde motion. The four-component Chandler wobble model 'explains' the apparent phase reversal during 1920-1940 and the pre-1950 empirical period-amplitude relation. The annual wobble is shown to be rather stationary over the years both in amplitude and in phase, and no evidence is found to support the large variations reported by earlier investigations. The Markowitz wobble is found to be marginally retrograde and appears to have a complicated behavior which cannot be resolved because of the shortness of the data set.

  17. Urban Water Conservation

    NASA Astrophysics Data System (ADS)

    Moomaw, Ronald L.

    According to its abstract, this book attempts ‘an assessment of various water conservation measures aimed at reducing residential water usage.’ Its intent is to develop a research program whose ‘ultimate goal is to engender a conservation ethic among water users and managers and develop a predictable array of conservation methodologies. …’ Professor Flack indeed has presented an excellent assessment of conservation methodologies, but I believe that the proposed research program is too limited.Following a brief introductory chapter, chapter II presents an extensive review of the water conservation literature published in the 1970's and earlier. It and chapter III, which describes Flack's systematic comparison of the technical, economic, and political aspects of each conservation methodology, are the heart of the book. Chapter IV is a brief discussion and analysis of conservation programs (with examples) that a water utility might adopt. Chapter V is essentially a pilot study of methods of assessing political and social feasibility. Finally, a set of recommendations is presented in chapter VI. All in all, this book is a nice blend of literature review and original research that deals with an important issue.

  18. Autoregressive harmonic analysis of the earth's polar motion using homogeneous international latitude service data

    NASA Astrophysics Data System (ADS)

    Fong Chao, B.

    1983-12-01

    The homogeneous set of 80-year-long (1900-1979) International Latitude Service (ILS) polar motion data is analyzed using the autoregressive method (Chao and Gilbert, 1980) which resolves and produces estimates for the complex frequency (or frequency and Q) and complex amplitude (or amplitude and phase) of each harmonic component in the data. Principal conclusion of this analysis are that (1) the ILS data support the multiple-component hypothesis of the Chandler wobble (it is found that the Chandler wobble can be adequately modeled as a linear combination of four (coherent) harmonic components, each of which represents a steady, nearly circular, prograte motion, a behavior that is inconsistent with the hypothesis of a single Chandler period excited in a temporally and/or spatially random fashion). (2) the four-component Chandler wobble model ``explains'' the apparent phase reversal during 1920-1940 and the pre-1950 empirical period-amplitude relation, (3) the annual wobble is shown to be rather stationary over the years both in amplitude and in phase and no evidence is found to support the large variations reported by earlier investigations. (4) the Markowitz wobble is found to support the large variations reported by earlier investigations. (4) the Markowitz wobble is found to be marginally retrograde and appears to have a complicated behavior which cannot be resolved because of the shortness of the data set.

  19. Investigation of the recognition of an important uridine in an internal loop of a hairpin ribozyme prepared using post-synthetically modified oligonucleotides.

    PubMed Central

    Komatsu, Y; Kumagai, I; Ohtsuka, E

    1999-01-01

    We introduced 4-thio- ((4S)U), 2-thio- ((2S)U), 4- O -methyluridine ((4Me)U) and cytidine substitutions for U+2, which is an important base for cleavage in a substrate RNA. Oligonucleotides containing 4-thio- and 4- O -methyluridine were prepared by a new convenient post-synthetic modification method using a 4- O - p -nitrophenyl-uridine derivative. A hairpin ribozyme cleaved the substrate RNA with either C+2, (4S)U+2 or (4Me)U+2 at approximately 14-, 6- and 4-fold lower rates, respectively, than that of the natural substrate. In contrast, the substrate with a (2S)U+2 was cleaved with the same activity as the natural substrate. These results suggest that the O4 of U+2 is involved in hydrogen bonding at loop A, but the O2 of U+2 is not recognized by the active residues. Circular dichroism data of the ribozymes containing (4S)U+2 and (2S)U+2, as well as the susceptibility of the thiocarbonyl group to hydrogen peroxide, suggest that a conformational change of U+2 occurs during the domain docking in the cleavage reaction. We propose here the conformational change of U+2 from the ground state to the active molecule during the reaction. PMID:10536137

  20. Influence of uridine diphosphate glucuronosyltransferase 2B7 -161C>T polymorphism on the concentration of valproic acid in pediatric epilepsy patients.

    PubMed

    Inoue, Kazuyuki; Suzuki, Eri; Yazawa, Rei; Yamamoto, Yoshiaki; Takahashi, Toshiki; Takahashi, Yukitoshi; Imai, Katsumi; Koyama, Seiichi; Inoue, Yushi; Tsuji, Daiki; Hayashi, Hideki; Itoh, Kunihiko

    2014-06-01

    Valproic acid (VPA) is widely used to treat various types of epilepsy. Interindividual variability in VPA pharmacokinetics may arise from genetic polymorphisms of VPA-metabolizing enzymes. This study aimed to examine the relationships between plasma VPA concentrations and the -161C>T single nucleotide polymorphism in uridine diphosphate glucuronosyltransferase (UGT) 2B7 genes in pediatric epilepsy patients. This study included 78 pediatric epilepsy patients carrying the cytochrome P450 (CYP) 2C9*1/*1 genotype and who were not treated with the enzyme inducers (phenytoin, phenobarbital, and carbamazepine), lamotrigine, and/or topiramate. CYP2C9*3 and UGT2B7 -161C>T polymorphisms were identified using methods based on polymerase chain reaction-restriction fragment length polymorphism. Blood samples were drawn from each patient under steady-state conditions, and plasma VPA concentrations were measured. Significant differences in adjusted plasma VPA concentrations were observed between carriers of CC, CT, and TT genotypes in the UGT2B7 -161C>T polymorphism (P = 0.039). Patients with the CC genotype had lower adjusted plasma VPA concentrations than those with CT or TT genotype (P = 0.028). These data suggest that the UGT2B7 -161C>T polymorphism in pediatric epilepsy patients carrying the CYP2C9*1/*1 genotype affects VPA concentration.

  1. Physiology, behavior, and conservation.

    PubMed

    Cooke, Steven J; Blumstein, Daniel T; Buchholz, Richard; Caro, Tim; Fernández-Juricic, Esteban; Franklin, Craig E; Metcalfe, Julian; O'Connor, Constance M; St Clair, Colleen Cassady; Sutherland, William J; Wikelski, Martin

    2014-01-01

    Many animal populations are in decline as a result of human activity. Conservation practitioners are attempting to prevent further declines and loss of biodiversity as well as to facilitate recovery of endangered species, and they often rely on interdisciplinary approaches to generate conservation solutions. Two recent interfaces in conservation science involve animal behavior (i.e., conservation behavior) and physiology (i.e., conservation physiology). To date, these interfaces have been considered separate entities, but from both pragmatic and biological perspectives, there is merit in better integrating behavior and physiology to address applied conservation problems and to inform resource management. Although there are some institutional, conceptual, methodological, and communication-oriented challenges to integrating behavior and physiology to inform conservation actions, most of these barriers can be overcome. Through outlining several successful examples that integrate these disciplines, we conclude that physiology and behavior can together generate meaningful data to support animal conservation and management actions. Tangentially, applied conservation and management problems can, in turn, also help advance and reinvigorate the fundamental disciplines of animal physiology and behavior by providing advanced natural experiments that challenge traditional frameworks.

  2. Conservation without borders: building communication and action across disciplinary boundaries for effective conservation.

    PubMed

    Margles, Shawn W; Peterson, Richard B; Ervin, Jamison; Kaplin, Beth A

    2010-01-01

    Interdisciplinary approaches to conservation research and environmental management continue to garner interest among practitioners, academics, and students. Yet, cases of practitioners and researchers from different disciplines successfully working in concert towards an integrated conservation approach are rare. What is preventing practitioners of multiple disciplines from harmoniously working together? Why are practitioners and academics struggling to apply their graduate training to real world conservation? What is preventing the benefits of cooperation and partnerships between different disciplines addressing conservation from being realized? This special issue "Conservation without Borders: Building Communication and Action across Disciplinary Boundaries for Effective Conservation" asks readers to consider the numerous interpretations and implications of the phrase "Conservation without Borders" and to reflect on how different academic and disciplinary lenses can contribute to a more integrated approach to tackling conservation challenges. The articles that comprise this special issue offer readers insights into the ways in which different disciplines view conservation work and interdisciplinary approaches to environmental problems. Bringing these perspectives and approaches together in one place is a step towards improving communication across disciplines for the purpose of achieving more successful biodiversity conservation.

  3. Discovery of 1-((2R,4aR,6R,7R,7aR)-2-Isopropoxy-2-oxidodihydro-4H,6H-spiro[furo[3,2-d][1,3,2]dioxaphosphinine-7,2'-oxetan]-6-yl)pyrimidine-2,4(1H,3H)-dione (JNJ-54257099), a 3'-5'-Cyclic Phosphate Ester Prodrug of 2'-Deoxy-2'-Spirooxetane Uridine Triphosphate Useful for HCV Inhibition.

    PubMed

    Jonckers, Tim H M; Tahri, Abdellah; Vijgen, Leen; Berke, Jan Martin; Lachau-Durand, Sophie; Stoops, Bart; Snoeys, Jan; Leclercq, Laurent; Tambuyzer, Lotke; Lin, Tse-I; Simmen, Kenny; Raboisson, Pierre

    2016-06-23

    JNJ-54257099 (9) is a novel cyclic phosphate ester derivative that belongs to the class of 2'-deoxy-2'-spirooxetane uridine nucleotide prodrugs which are known as inhibitors of the HCV NS5B RNA-dependent RNA polymerase (RdRp). In the Huh-7 HCV genotype (GT) 1b replicon-containing cell line 9 is devoid of any anti-HCV activity, an observation attributable to inefficient prodrug metabolism which was found to be CYP3A4-dependent. In contrast, in vitro incubation of 9 in primary human hepatocytes as well as pharmacokinetic evaluation thereof in different preclinical species reveals the formation of substantial levels of 2'-deoxy-2'-spirooxetane uridine triphosphate (8), a potent inhibitor of the HCV NS5B polymerase. Overall, it was found that 9 displays a superior profile compared to its phosphoramidate prodrug analogues (e.g., 4) described previously. Of particular interest is the in vivo dose dependent reduction of HCV RNA observed in HCV infected (GT1a and GT3a) human hepatocyte chimeric mice after 7 days of oral administration of 9.

  4. Fixism and conservation science.

    PubMed

    Robert, Alexandre; Fontaine, Colin; Veron, Simon; Monnet, Anne-Christine; Legrand, Marine; Clavel, Joanne; Chantepie, Stéphane; Couvet, Denis; Ducarme, Frédéric; Fontaine, Benoît; Jiguet, Frédéric; le Viol, Isabelle; Rolland, Jonathan; Sarrazin, François; Teplitsky, Céline; Mouchet, Maud

    2017-08-01

    The field of biodiversity conservation has recently been criticized as relying on a fixist view of the living world in which existing species constitute at the same time targets of conservation efforts and static states of reference, which is in apparent disagreement with evolutionary dynamics. We reviewed the prominent role of species as conservation units and the common benchmark approach to conservation that aims to use past biodiversity as a reference to conserve current biodiversity. We found that the species approach is justified by the discrepancy between the time scales of macroevolution and human influence and that biodiversity benchmarks are based on reference processes rather than fixed reference states. Overall, we argue that the ethical and theoretical frameworks underlying conservation research are based on macroevolutionary processes, such as extinction dynamics. Current species, phylogenetic, community, and functional conservation approaches constitute short-term responses to short-term human effects on these reference processes, and these approaches are consistent with evolutionary principles. © 2016 Society for Conservation Biology.

  5. Borate-aided anion exchange high-performance liquid chromatography of uridine diphosphate-sugars in brain, heart, adipose and liver tissues.

    PubMed

    Oikari, Sanna; Venäläinen, Tuula; Tammi, Markku

    2014-01-03

    In this paper we describe a method optimized for the purification of uridine diphosphate (UDP)-sugars from liver, adipose tissue, brain, and heart, with highly reproducible up to 85% recoveries. Rapid tissue homogenization in cold ethanol, lipid removal by butanol extraction, and purification with a graphitized carbon column resulted in isolation of picomolar quantities of the UDP-sugars from 10 to 30mg of tissue. The UDP-sugars were baseline separated from each other, and from all major nucleotides using a CarboPac PA1 anion exchange column eluted with a gradient of acetate and borate buffers. The extraction and purification protocol produced samples with few unidentified peaks. UDP-N-acetylglucosamine was a dominant UDP-sugar in all the rat tissues studied. However, brain and adipose tissue showed high UDP-glucose levels, equal to that of UDP-N-acetylglucosamine. The UDP-N-acetylglucosamine showed 2.3-2.7 times higher levels than UDP-N-acetylgalactosamine in all tissues, and about the same ratio was found between UDP-glucose and UDP-galactose in adipose tissue and brain (2.6 and 2.8, respectively). Interestingly, the UDP-glucose/UDP-galactose ratio was markedly lower in liver (1.1) and heart (1.7). The UDP-N-acetylglucosamine/UDP-glucuronic acid ratio was also constant, between 9.7 and 7.7, except in liver with the ratio as low as 1.8. The distinct UDP-glucose/galactose ratio, and the abundance of UDP-glucuronic acid may reflect the specific role of liver in glycogen synthesis, and metabolism of hormones and xenobiotics, respectively, using these UDP-sugars as substrates. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Complex formation of divalent metal ions with uridine 5'-O-thiomonophosphate or methyl thiophosphate: comparison of complex stabilities with those of the parent phosphate ligands.

    PubMed

    Da Costa, Carla P; Okruszek, Andrzej; Sigel, Helmut

    2003-07-07

    The stability constants of the 1:1 complexes formed in aqueous solution between Mg2+, Ca2+, Sr2+, Ba2+, Mn2+, Co2+, Ni2+, Zn2+, or Cd2+ (M2+) and methyl thiophosphate (MeOPS(2-)) or uridine 5'-O-thiomonophosphate (UMPS(2-)) (PS(2-)=MeOPS(2-) or UMPS(2-)) have been determined (potentiometric pH titrations; 25 degrees C; I = 0.1 M, NaNO(3)). Comparison of these results for M(PS) complexes with those known for the parent M(PO) phosphate species, where PO(2-)=CH(3)OPO(2-)(3) or UMP(2-) (uridine 5'-monophosphate), shows that the alkaline earth metal ions, as well as Mn2+, Co2+, and Ni2+ have a higher affinity for phosphate groups than for their thio analogues. However, based on the linear log K(M)(M(R-PO3)) versus pK(H)(H(R-PO3)) relationships (R-PO(2-)(3) simple phosphate monoester or phosphonate ligands with a non-interacting residue R) it becomes clear that the indicated observation is only the result of the lower basicity of the thiophosphate residue. In contrast, the thio complexes of Zn2+ and Cd2+ are more stable than their parent phosphate ones, and this despite the lower basicity of the PS(2-) ligands. This stability increase is identical for M(MeOPS) and M(UMPS) species and amounts to about 0.6 and 2.4 log units for Zn(PS) and Cd(PS), respectively. Since no other binding site is available in MeOPS(2-), this enhanced stability has to be attributed to the S atom. Indeed, from the mentioned stability differences it follows that Cd2+ in Cd(PS) is coordinated by more than 99% to the thiophosphate S atom; the same value holds for Pb(PS), which was studied earlier. The formation degree of the Sbonded isomer amounts to 76+/-6 % for Zn(PS) and is close to zero for the corresponding Mg2+, Ca2+, and Mn2+ species. It is further shown that Zn(MeOPS)(aq)(2+) releases a proton from a coordinated water molecule with pK(a) approximately 6.9; i.e., this deprotonation occurs at a lower pH value than that for the same reaction in Zn(aq)(2+). Since Mg2+, Ca2+, Mn2+, and Cd2+ have a

  7. Discrimination of epimeric glycans and glycopeptides using IM-MS and its potential for carbohydrate sequencing

    NASA Astrophysics Data System (ADS)

    Both, P.; Green, A. P.; Gray, C. J.; Šardzík, R.; Voglmeir, J.; Fontana, C.; Austeri, M.; Rejzek, M.; Richardson, D.; Field, R. A.; Widmalm, G.; Flitsch, S. L.; Eyers, C. E.

    2014-01-01

    Mass spectrometry is the primary analytical technique used to characterize the complex oligosaccharides that decorate cell surfaces. Monosaccharide building blocks are often simple epimers, which when combined produce diastereomeric glycoconjugates indistinguishable by mass spectrometry. Structure elucidation frequently relies on assumptions that biosynthetic pathways are highly conserved. Here, we show that biosynthetic enzymes can display unexpected promiscuity, with human glycosyltransferase pp-α-GanT2 able to utilize both uridine diphosphate N-acetylglucosamine and uridine diphosphate N-acetylgalactosamine, leading to the synthesis of epimeric glycopeptides in vitro. Ion-mobility mass spectrometry (IM-MS) was used to separate these structures and, significantly, enabled characterization of the attached glycan based on the drift times of the monosaccharide product ions generated following collision-induced dissociation. Finally, ion-mobility mass spectrometry following fragmentation was used to determine the nature of both the reducing and non-reducing glycans of a series of epimeric disaccharides and the branched pentasaccharide Man3 glycan, demonstrating that this technique may prove useful for the sequencing of complex oligosaccharides.

  8. Effect of the use of combination uridine triphosphate, cytidine monophosphate, and hydroxycobalamin on the recovery of neurosensory disturbance after bilateral sagittal split osteotomy: a randomized, double-blind trial.

    PubMed

    Vieira, C L; Vasconcelos, B C do E; Leão, J C; Laureano Filho, J R

    2016-02-01

    The change in neurosensory lesions that develop after bilateral sagittal split osteotomy (BSSO) was explored, and the influence of the application of combination uridine triphosphate (UTP), cytidine monophosphate (CMP), and hydroxycobalamin (vitamin B12) on patient outcomes was assessed. This was a randomized, controlled, double-blind trial. The study sample comprised 12 patients, each evaluated on both sides (thus 24 sides). All patients fulfilled defined selection criteria. Changes in the lesions were measured both subjectively and objectively. The sample was divided into two patient groups: an experimental group receiving medication and a control group receiving placebo. The statistical analysis was performed using SPSS software. Lesions in both groups improved and no statistically significant difference between the groups was observed at any time. 'Severe' injuries in the experimental group were more likely to exhibit a significant improvement after 6 months. Based on the results of the present study, it is concluded that the combination UTP, CMP, and hydroxycobalamin did not influence recovery from neurosensory disorders. Copyright © 2015. Published by Elsevier Ltd.

  9. 76 FR 57515 - Energy Conservation Program: Energy Conservation Standards for Residential Refrigerators...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-15

    ...The Energy Policy and Conservation Act (EPCA) prescribes energy conservation standards for various consumer products and commercial and industrial equipment, including refrigerators, refrigerator-freezers, and freezers. EPCA also requires the U.S. Department of Energy (DOE) to determine if more stringent, amended standards for these products are technologically feasible and economically justified, and would save a significant amount of energy. In this final rule, DOE is adopting more stringent energy conservation standards for refrigerators, refrigerator-freezers, and freezers. It has determined that the amended energy conservation standards for these products would result in the significant conservation of energy and are technologically feasible and economically justified.

  10. Conservation of energy resources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mauss, E.A.; Ullmann, J.E.

    1979-01-01

    The following papers are included: Social, Political, and Ethical Choices in Developing Energy Policies by John C. Sawhill; Choices in Developing Energy Choices by Amory B. Lovins; Energy Conservation: Some Technical and Economic Possibilities by Lloyd J. Thomas; Four Anxieties about a Vigorous National Conservation Program by R. H. Socolow; Energy Conservation: The Weight of the Past and the Problems of Persuasion by John E. Ullman; The Energy Value of Our Existing Stock of Buildings by Richard G. Stein; The Role of Energy Conservation in Industry by Eric R. Zausner; The Role of Energy Conservation in Industry: Discussion Paper bymore » Charles A. Berg; End-Use Technology: The Next Twenty-Five Years by George R. Murray and Michael Power; The Department of Energy's End-Use Conservation Program by Marc Ross; and The Politics of Energy Conservation by Daniel Yergin. (MHR)« less

  11. Prioritizing trees for global conservation action: BGCI’s tree conservation agenda

    Treesearch

    K. Shaw; M. Rivers; E. Beech

    2017-01-01

    Botanic Gardens Conservation International (BGCI) is a global voice for plant conservation via its worldwide network of botanic gardens and partners. Tree conservation has been a strong focus of BGCI’s program for many years. In collaboration with Fauna & Flora International, BGCI runs the Global Trees Campaign (GTC, www.globaltrees.org), the only international...

  12. 7 CFR 12.23 - Conservation plans and conservation systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... to produce agricultural commodities prior to December 23, 1985, the applicable conservation systems... available conservation technology; cost-effective; and shall not cause undue economic hardship on the person... containing highly erodible cropland which was used to produce an agricultural commodity prior to December 23...

  13. Industrial hearing conservation.

    PubMed

    Glorig, A

    1979-08-01

    Hearing conservation programs, when appropriate in industry, are now a necessity. Even though one may not wish to adopt an altruistic attitude toward the conservation of hearing, one must, like it or not, initiate a hearing conservation program because of both federal and state regulations. Since industrial noise exposure produced more hearing loss in more people than all other causes of hearing loss combined, it is incumbent on all industries with noise makers to do something about protecting human hearing. The tragedy is that nearly all industrial hearing loss can be prevented with proper hearing conservation measures. The cost of hearing conservation is far less than the cost of hearing loss in terms of human suffering and dollars in the compensation courts. Proper education of both managment and labor can result in successful hearing conservation programs. The method of choice is reduction of the noise at the source, but in many cases this is infeasible both technically and economically and therefore protection at the ear must be used. Experience has shown that with proper supervision ear protection programs can prevent the majority of instances of hearing loss in the majority of individuals exposed.

  14. REVIEW: The evolving linkage between conservation science and practice at The Nature Conservancy.

    PubMed

    Kareiva, Peter; Groves, Craig; Marvier, Michelle

    2014-10-01

    The Nature Conservancy (TNC) was founded by ecologists as a United States land trust to purchase parcels of habitat for the purpose of scientific study. It has evolved into a global organization working in 35 countries 'to conserve the lands and waters on which all life depends'. TNC is now the world 's largest conservation non-governmental organization (NGO), an early adopter of advances in ecological theory and a producer of new science as a result of practising conservation.The Nature Conservancy 's initial scientific innovation was the use of distributional data for rare species and ecological communities to systematically target lands for conservation. This innovation later evolved into a more rigorous approach known as 'Conservation by Design' that contained elements of systematic conservation planning, strategic planning and monitoring and evaluation.The next scientific transition at TNC was a move to landscape-scale projects, motivated by ideas from landscape ecology. Because the scale at which land could be set aside in areas untouched by humans fell far short of the spatial scale demanded by conservation, TNC became involved with best management practices for forestry, grazing, agriculture, hydropower and other land uses.A third scientific innovation at TNC came with the pursuit of multiobjective planning that accounts for economic and resource needs in the same plans that seek to protect biodiversity.The Millennium Ecosystem Assessment prompted TNC to become increasingly concerned with ecosystem services and the material risk to people posed by ecosystem deterioration.Finally, because conservation depends heavily upon negotiation, TNC has recently recruited social scientists, economists and communication experts. One aspect still missing, however, is a solid scientific understanding of thresholds that should be averted. Synthesis and applications . Over its 60-plus year history, scientific advances have informed The Nature Conservancy (TNC) 's actions

  15. REVIEW: The evolving linkage between conservation science and practice at The Nature Conservancy

    PubMed Central

    Kareiva, Peter; Groves, Craig; Marvier, Michelle

    2014-01-01

    The Nature Conservancy (TNC) was founded by ecologists as a United States land trust to purchase parcels of habitat for the purpose of scientific study. It has evolved into a global organization working in 35 countries ‘to conserve the lands and waters on which all life depends’. TNC is now the world 's largest conservation non-governmental organization (NGO), an early adopter of advances in ecological theory and a producer of new science as a result of practising conservation.The Nature Conservancy 's initial scientific innovation was the use of distributional data for rare species and ecological communities to systematically target lands for conservation. This innovation later evolved into a more rigorous approach known as ‘Conservation by Design’ that contained elements of systematic conservation planning, strategic planning and monitoring and evaluation.The next scientific transition at TNC was a move to landscape-scale projects, motivated by ideas from landscape ecology. Because the scale at which land could be set aside in areas untouched by humans fell far short of the spatial scale demanded by conservation, TNC became involved with best management practices for forestry, grazing, agriculture, hydropower and other land uses.A third scientific innovation at TNC came with the pursuit of multiobjective planning that accounts for economic and resource needs in the same plans that seek to protect biodiversity.The Millennium Ecosystem Assessment prompted TNC to become increasingly concerned with ecosystem services and the material risk to people posed by ecosystem deterioration.Finally, because conservation depends heavily upon negotiation, TNC has recently recruited social scientists, economists and communication experts. One aspect still missing, however, is a solid scientific understanding of thresholds that should be averted.Synthesis and applications. Over its 60-plus year history, scientific advances have informed The Nature Conservancy (TNC) 's

  16. Community motivations to engage in conservation behavior to conserve the Sumatran orangutan.

    PubMed

    Nilsson, Danielle; Gramotnev, Galina; Baxter, Greg; Butler, James R A; Wich, Serge A; McAlpine, Clive A

    2016-08-01

    Community-based conservation programs in developing countries are often based on the assumption that heteronomous motivation (e.g., extrinsic incentives such as economic rewards and pressure or coercion to act) will incite local communities to adopt conservation behaviors. However, this may not be as effective or sustainable as autonomous motivations (e.g., an intrinsic desire to act due to inherent enjoyment or self-identification with a behavior and through freedom of choice). We analyzed the comparative effectiveness of heteronomous versus autonomous approaches to community-based conservation programs through a case study of Sumatran orangutan (Pongo abelii) conservation in 3 villages in Indonesia. Each village had a different conservation program design. We surveyed people (n = 240) to determine their motivations for and behavior changes relative to orangutan and orangutan habitat (forest) protection. Heteronomous motivations (e.g., income from tourism) led to greater self-reporting of behavior change toward orangutan protection. However, they did not change self-reported behavior toward forest (i.e., orangutan habitat) protection. The most effective approach to creating self-reported behavior change throughout the community was a combination of autonomous and heteronomous motivations. Individuals who were heteronomously motivated to protect the orangutan were more likely to have changed attitudes than to have changed their self-reported behavior. These findings demonstrate that the current paradigm of motivating communities in developing countries to adopt conservation behaviors primarily through monetary incentives and rewards should consider integrating autonomous motivational techniques that promote the intrinsic values of conservation. Such a combination has a greater potential to achieve sustainable and cost-effective conservation outcomes. Our results highlight the importance of using in-depth sociopsychological analyses to inform the design and

  17. 7 CFR 12.23 - Conservation plans and conservation systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... in the field office technical guide are designed to achieve substantial reductions in soil erosion..., 1985, the measurement of erosion reduction achieved by applying a conservation plan or system shall be... in paragraph (b) which the conservation system or plan was designed to achieve. It is the...

  18. 76 FR 793 - Multistate Conservation Grant Program; Priority List for Conservation Projects

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-06

    ...; 91400-9410-0000-7B] Multistate Conservation Grant Program; Priority List for Conservation Projects... 2011 priority list of wildlife and sport fish conservation projects from the Association of Fish and Wildlife Agencies (AFWA). As required by the Wildlife and Sport Fish Restoration Programs Improvement Act...

  19. Paradigms for parasite conservation.

    PubMed

    Dougherty, Eric R; Carlson, Colin J; Bueno, Veronica M; Burgio, Kevin R; Cizauskas, Carrie A; Clements, Christopher F; Seidel, Dana P; Harris, Nyeema C

    2016-08-01

    Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite-inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid-20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host-density threshold and cost-benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host-parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of

  20. Biodiversity conservation in local planning.

    PubMed

    Miller, James R; Groom, Martha; Hess, George R; Steelman, Toddi; Stokes, David L; Thompson, Jan; Bowman, Troy; Fricke, Laura; King, Brandon; Marquardt, Ryan

    2009-02-01

    Local land-use policy is increasingly being recognized as fundamental to biodiversity conservation in the United States. Many planners and conservation scientists have called for broader use of planning and regulatory tools to support the conservation of biodiversity at local scales. Yet little is known about the pervasiveness of these practices. We conducted an on-line survey of county, municipal, and tribal planning directors (n =116) in 3 geographic regions of the United States: metropolitan Seattle, Washington; metropolitan Des Moines, Iowa; and the Research Triangle, North Carolina. Our objectives were to gauge the extent to which local planning departments address biodiversity conservation and to identify factors that facilitate or hinder conservation actions in local planning. We found that biodiversity conservation was seldom a major consideration in these departments. Staff time was mainly devoted to development mandates and little time was spent on biodiversity conservation. Regulations requiring conservation actions that might benefit biodiversity were uncommon, with the exception of rules governing water quality in all 3 regions and the protection of threatened and endangered species in the Seattle region. Planning tools that could enhance habitat conservation were used infrequently. Collaboration across jurisdictions was widespread, but rarely focused on conservation. Departments with a conservation specialist on staff tended to be associated with higher levels of conservation actions. Jurisdictions in the Seattle region also reported higher levels of conservation action, largely driven by state and federal mandates. Increased funding was most frequently cited as a factor that would facilitate greater consideration of biodiversity in local planning. There are numerous opportunities for conservation biologists to play a role in improving conservation planning at local scales.

  1. Conservation: Toward firmer ground

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The following aspects of energy conservation were reviewed in order to place the problems in proper perspective: history and goals, conservation accounting-criteria, and a method to overcome obstacles. The effect of changing prices and available supplies of energy sources and their causes on consumption levels during the last few decades were described. Some examples of attainable conservation goals were listed and justified. A number of specific criteria applicable to conservation accounting were given. Finally, a discussion was presented to relate together the following aspects of energy conservation: widespread impact, involvement of government, industry, politics, moral and ethical aspects, urgency and time element.

  2. 75 FR 11194 - San Diego County Water Authority Natural Communities Conservation Program/Habitat Conservation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... Diego County Water Authority Natural Communities Conservation Program/Habitat Conservation Plan, San... meetings for the San Diego County Water Authority's (Water Authority/Applicant) draft Natural Communities Conservation Plan (NCCP)/Habitat Conservation Plan (HCP) prepared in application to us for an incidental take...

  3. Gravitational torque on the inner core and decadal polar motion

    NASA Astrophysics Data System (ADS)

    Dumberry, Mathieu

    2008-03-01

    A decadal polar motion with an amplitude of approximately 25 milliarcsecs (mas) is observed over the last century, a motion known as the Markowitz wobble. The origin of this motion remains unknown. In this paper, we investigate the possibility that a time-dependent axial misalignment between the density structures of the inner core and mantle can explain this signal. The longitudinal displacement of the inner core density structure leads to a change in the global moment of inertia of the Earth. In addition, as a result of the density misalignment, a gravitational equatorial torque leads to a tilt of the oblate geometric figure of the inner core, causing a further change in the global moment of inertia. To conserve angular momentum, an adjustment of the rotation vector must occur, leading to a polar motion. We develop theoretical expressions for the change in the moment of inertia and the gravitational torque in terms of the angle of longitudinal misalignment and the density structure of the mantle. A model to compute the polar motion in response to time-dependent axial inner core rotations is also presented. We show that the polar motion produced by this mechanism can be polarized about a longitudinal axis and is expected to have decadal periodicities, two general characteristics of the Markowitz wobble. The amplitude of the polar motion depends primarily on the Y12 spherical harmonic component of mantle density, on the longitudinal misalignment between the inner core and mantle, and on the bulk viscosity of the inner core. We establish constraints on the first two of these quantities from considerations of the axial component of this gravitational torque and from observed changes in length of day. These constraints suggest that the maximum polar motion from this mechanism is smaller than 1 mas, and too small to explain the Markowitz wobble.

  4. 76 FR 22453 - Energy Conservation Program: Energy Conservation Standards for Residential Clothes Dryers and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-21

    .... These impacts continue well beyond 2100. Table I-3 shows the annualized values for the clothes dryer... Conservation Program: Energy Conservation Standards for Residential Clothes Dryers and Room Air Conditioners... 1904-AA89 Energy Conservation Program: Energy Conservation Standards for Residential Clothes Dryers and...

  5. 75 FR 23191 - Energy Conservation Program for Consumer Products: Energy Conservation Standards for Certain...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-03

    ...-BT-STD-0005] RIN 1904-AC15 Energy Conservation Program for Consumer Products: Energy Conservation... Conservation Act (EPCA), the U.S. Department of Energy (DOE) is preparing a notice of proposed rulemaking regarding energy conservation standards for certain incandescent reflector lamps (IRLs) that have elliptical...

  6. 75 FR 12144 - Energy Conservation Program for Consumer Products: Energy Conservation Standards for Residential...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-15

    ...-2009-BT-STD-0022] RIN 1904-AC06 Energy Conservation Program for Consumer Products: Energy Conservation... that DOE plans to analyze for purposes of amending energy conservation standards for certain... persons may submit comments, identified by the notice title, the NOPM for Energy Conservation Standards...

  7. Conservation Through Different Lenses: Reflection, Responsibility, and the Politics of Participation in Conservation Advocacy

    NASA Astrophysics Data System (ADS)

    Abrash Walton, Abigail

    2010-01-01

    This essay considers the arenas of advocacy, politics, and self-reflection in strengthening conservation and resource management initiatives. It frames key questions that reflective conservation practitioners may address in seeking to enhance the results of conservation projects, including equity and more inclusive participation by nonprivileged groups. The essay touches on the importance of understanding conservation work within particular political and historic dynamics, including the need to understand non-Western and/or indigenous or traditional perspectives on conservation. The author makes the case that Western or privileged conservation practitioners are uniquely situated to advocate effectively for change.

  8. 3-Methyl-4-nitrophenol metabolism by uridine diphosphate glucuronosyltransferase and sulfotransferase in liver microsomes of mice, rats, and Japanese quail (Coturnix japonica).

    PubMed

    Lee, Chul-Ho; Kamijima, Michihiro; Li, ChunMei; Taneda, Shinji; Suzuki, Akira K; Nakajima, Tamie

    2007-09-01

    3-Methyl-4-nitrophenol (PNMC) is a component of diesel exhaust particles and one of the major breakdown products of the insecticide fenitrothion. This chemical has a high potential for reproductive toxicity in Japanese quail (Coturnix japonica) and rats. Because PNMC inhaled by the body is metabolized by uridine diphosphate glucuronosyltransferase (UGT) and sulfotransferase, we investigated these enzyme activities in the hepatic microsomes and cytosols of quail (as a model of wild birds) and compared these activities with those of rats and mice as models of ecological and human risk assessment. The maximum velocity of the UGT for PNMC in quail was 12.7 nmol/min/mg, which was one third and one fourth those of rats and mice, respectively. The Michaelis-Menten constant of UGT for PNMC in quail was 0.29 mM, which was 1.3- and 1.8-fold higher than that in mice and rats, respectively, but not significantly different. In accordance with these results, UGT activities for PNMC were lowest in quail, with those in mice and rats being 4.4- and 2.7-fold higher, respectively. Sulfotransferase activity for PNMC was considerably less than that of UGT in all animals, including quail; no significant differences in the activities were found among mice, rats, and quail. These results suggest that glucuronidation may be involved primarily in PNMC elimination from wild birds as well as mammals and that the UGT activity in quail is less than that in the rodents.

  9. 78 FR 25093 - Multistate Conservation Grant Program; Priority List and Approval for Conservation Projects

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... Fish Restoration Act (16 U.S.C. 777 et seq.) and established the Multistate Conservation Grant Program...-9410-0000] Multistate Conservation Grant Program; Priority List and Approval for Conservation Projects... year 2013 priority list of wildlife and sport fish conservation projects from the Association of Fish...

  10. Conservation: Toward firmer ground

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The following aspects of energy conservation were discussed: conservation history and goals, conservation modes, conservation accounting-criteria, and a method to overcome obstacles. The conservation modes tested fall into one of the following categories: reduced energy consumption, increased efficiency of energy utilization, or substitution of one or more forms of energy for another which is in shorter supply or in some sense thought to be of more value. The conservation accounting criteria include net energy reduction, economic, and technical criteria. A method to overcome obstacles includes (approaches such as: direct personal impact (life style, income, security, aspiration), an element of crisis, large scale involvement of environmental, safety, and health issues, connections to big government, big business, big politics, involvement of known and speculative science and technology, appeal to moral and ethical standards, the transient nature of opportunities to correct the system.

  11. Comparative analysis of three-dimensional structures of homodimers of uridine phosphorylase from Salmonella typhimurium in the unligated state and in a complex with potassium ion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lashkov, A. A.; Zhukhlistova, N. E.; Gabdulkhakov, A. G.

    2009-03-15

    The spatial organization of the homodimer of unligated uridine phosphorylase from Salmonella typhimurium (St UPh) was determined with high accuracy. The structure was refined at 1.80 A resolution to R{sub work} = 16.1% and R{sub free} = 20.0%. The rms deviations for the bond lengths, bond angles, and chiral angles are 0.006 A, 1.042{sup o}, and 0.071{sup o}, respectively. The coordinate error estimated by the Luzzati plot is 0.166 A. The coordinate error based on the maximum likelihood is 0.199 A. A comparative analysis of the spatial organization of the homodimer in two independently refined structures and the structure ofmore » the homodimer St UPh in the complex with a K{sup +} ion was performed. The substrate-binding sites in the homodimers StUPhs in the unligated state were found to act asynchronously. In the presence of a potassium ion, the three-dimensional structures of the subunits in the homodimer are virtually identical, which is apparently of importance for the synchronous action of both substrate-binding sites. The atomic coordinates of the refined structure of the homodimer and structure factors have been deposited in the Protein Data Bank (PDB ID code 3DPS).« less

  12. Frequency of uridine monophosphate synthase Gly(213)Ala polymorphism in Caucasian gastrointestinal cancer patients and healthy subjects, investigated by means of new, rapid genotyping assays.

    PubMed

    Gusella, Milena; Bertolaso, Laura; Bolzonella, Caterina; Pasini, Felice; Padrini, Roberto

    2011-10-01

    Uridine monophosphate synthase (UMPS) is a fundamental enzyme in pyrimidine synthesis. A single-nucleotide polymorphism, a G-C transversion at the 638th nucleotide, was demonstrated to increase UMPS activity and suggested to have clinical effects. The aims of this study were to set up simple genotyping methods and investigate the UMPS 638G>C polymorphism in the Caucasian population. Two hundred forty-one patients with gastrointestinal cancers and 189 healthy subjects were enrolled. Genomic DNA was extracted from peripheral blood. A polymerase chain reaction-restriction fragment length polymorphism (RFLP) method was implemented using a forward primer incorporating a mismatched base to produce an artificial restriction site and BsrI restriction enzyme digestion; a denaturing high performance liquid chromatography (DHPLC) method was developed to further speed up UMPS genotyping. A 153 bp UMPS gene fragment was successfully amplified and analyzed in all samples. RFLP and DHPLC results showed a 100% match and where confirmed by direct sequencing. UMPS genotype distribution was similar in patients with cancer and control subjects. Although no association was detected between UMPS variants and gastrointestinal cancer risk in Caucasians, polymerase chain reaction-RFLP with BsrI digestion and DHPLC set up at 59°C are reliable and cost-effective methods to genotype UMPS.

  13. The Conservation Efforts Database: Improving our knowledge of landscape conservation actions

    USGS Publications Warehouse

    Heller, Matthew M.; Welty, Justin; Wiechman , Lief A.

    2017-01-01

    The Conservation Efforts Database (CED) is a secure, cloud-based tool that can be used to document and track conservation actions across landscapes. A recently released factsheet describes this tool ahead of the rollout of CED version 2.0. The CED was developed by the U.S. Fish and Wildlife Service, the USGS, and the Great Northern Landscape Conservation Cooperative to support the 2015 Endangered Species Act status review for greater sage-grouse. Currently, the CED accepts policy-level data, such as Land Use Plans, and treatment level data, such as conifer removals and post-fire recovery efforts, as custom spatial and non-spatial records. In addition to a species assessment tool, the CED can also be used to summarize the extent of restoration efforts within a specific area or to strategically site conservation actions based on the location of other implemented actions. The CED can be an important tool, along with post-conservation monitoring, for implementing landscape-scale adaptive management.

  14. Strategic conservation planning for the Eastern North Carolina/Southeastern Virginia Strategic Habitat Conservation Team

    USGS Publications Warehouse

    Alexander-Vaughn, Louise B.; Collazo, Jaime A.; Drew, C. Ashton

    2014-01-01

    The Eastern North Carolina/Southeastern Virginia Strategic Habitat Conservation Team (ENCSEVA) is a partnership among local federal agencies and programs with a mission to apply Strategic Habitat Conservation to accomplish priority landscape-level conservation within its geographic region. ENCSEVA seeks to further landscape-scale conservation through collaboration with local partners. To accomplish this mission, ENCSEVA is developing a comprehensive Strategic Habitat Conservation Plan (Plan) to provide guidance for its members, partners, and collaborators by establishing mutual conservation goals, objectives, strategies, and metrics to gauge the success of conservation efforts. Identifying common goals allows the ENCSEVA team to develop strategies that leverage joint resources and are more likely to achieve desired impacts across the landscape. The Plan will also provide an approach for ENCSEVA to meet applied research needs (identify knowledge gaps), foster adaptive management principles, identify conservation priorities, prioritize threats (including potential impacts of climate change), and identify the required capacity to implement strategies to create more resilient landscapes. ENCSEVA seeks to support the overarching goals of the South Atlantic Landscape Conservation Cooperative (SALCC) and to provide scientific and technical support for conservation at landscape scales as well as inform the management of natural resources in response to shifts in climate, habitat fragmentation and loss, and other landscape-level challenges (South Atlantic LCC 2012). The ENCSEVA ecoregion encompasses the northern third of the SALCC geography and offers a unique opportunity to apply landscape conservation at multiple scales through the guidance of local conservation and natural resource management efforts and by reporting metrics that reflect the effectiveness of those efforts (Figure 1). The Environmental Decision Analysis Team, housed within the North Carolina Cooperative

  15. Monitoring for conservation

    USGS Publications Warehouse

    Nichols, J.D.; Williams, B.K.

    2006-01-01

    Human-mediated environmental changes have resulted in appropriate concern for the conservation of ecological systems and have led to the development of many ecological monitoring programs worldwide. Many programs that are identified with the purpose of `surveillance? represent an inefficient use of conservation funds and effort. Here, we revisit the 1964 paper by Platt and argue that his recommendations about the conduct of science are equally relevant to the conduct of ecological monitoring programs. In particular, we argue that monitoring should not be viewed as a stand-alone activity, but instead as a component of a larger process of either conservation-oriented science or management. Corresponding changes in monitoring focus and design would lead to substantial increases in the efficiency and usefulness of monitoring results in conservation.

  16. Do Cyclosporine A, an IL-1 Receptor Antagonist, Uridine Triphosphate, Rebamipide, and/or Bimatoprost Regulate Human Meibomian Gland Epithelial Cells?

    PubMed

    Kam, Wendy R; Liu, Yang; Ding, Juan; Sullivan, David A

    2016-08-01

    Researchers have hypothesized that treatment with cyclosporine A (CyA), interleukin-1 receptor antagonists (IL-1RA; e.g., anakinra), P2Y2 receptor agonists (e.g., uridine triphosphate; UTP), and rebamipide may alleviate human meibomian gland dysfunction (MGD) and/or dry eye disease. Investigators have also proposed that prostaglandin analogues (e.g., bimatoprost) may induce MGD. Our goal was to determine whether these compounds directly influence human meibomian gland epithelial cell (HMGEC) function. Multiple concentrations of each compound were tested for effects on immortalized (I) HMGEC morphology and survival. Nontoxic dosages were used for our studies. Immortalized HMGEC were cultured in the presence of vehicle, CyA, IL-1RA, UTP, rebamipide, or bimatoprost for up to 6 days in various media. Experiments included positive controls for proliferation (epidermal growth factor and bovine pituitary extract), differentiation (azithromycin), and signaling pathway activation (insulin-like growth factor 1). Cells were analyzed for neutral lipid staining, lysosome accumulation, lipid composition, and phosphatidylinositol-3-kinase/Akt (AKT), phosphorylation. Our findings demonstrate that CyA, IL-1RA, UTP, rebamipide, and bimatoprost had no effect on the proliferation; neutral lipid content; lysosome number; or levels of free cholesterol, triglycerides, or phospholipids in IHMGECs. Cylosporine A, IL-1RA, rebamipide, and bimatoprost significantly reduced the phosphorylation of AKT, as compared to control. Of interest, tested doses of CyA above 8 nM killed the IHMGECs. Our results show that CyA, IL-1RA, UTP, rebamipide, and bimatoprost do not influence the proliferation or differentiation of IHMGEC. However, with the exception of UTP, these compounds do decrease the activity of the AKT signaling pathway, which is known to promote cell survival.

  17. Effect of the combination of uridine nucleotides, folic acid and vitamin B12 on the clinical expression of peripheral neuropathies.

    PubMed

    Negrão, Luis; Almeida, Pedro; Alcino, Sérgio; Duro, Helena; Libório, Teresa; Melo Silva, Ulisses; Figueira, Ricardo; Gonçalves, Sílvia; Neto Parra, Laura

    2014-05-01

    Peripheral neuropathy (PN) is a common condition whose incidence is approximately 8% in elderly persons. Neuropathic pain (NeP) has a significant incidence in the general population and affects more than half of all patients with PN. The pathophysiology of PN is characterized by lesions of myelin-producing Schwann cells in peripheral nerves. Regeneration/protection of the myelin sheath after a nerve lesion is a fundamental element of repair in PN. Nucleotides such as uridine monophosphate (UMP) have proven to be efficacious in treating the cause of the myelin sheath lesion in several experimental and clinical models. Our objective was to evaluate clinical improvement in patients with PN and NeP treated with a combination of UMP+folic acid+vitamin B12 (Keltican). We performed an exploratory, open-label, multicenter, study of 212 patients followed for 2 months. Pain was assessed using the painDETECT questionnaire (PDQ). The intensity of the NeP assessed at the time of the consultation progressed favorably and decreased significantly (p<0.001) in all the types of PN included. The global score for pain assessed using PDQ decreased from 17.5 points to 8.8 points at the final evaluation (p<0.001). Nonsteroidal anti-inflammatory drugs were decreased/withdrawn in 77.4% of patients. The combination of UMP+folic acid+vitamin B12 is effective against NeP associated with PN. It leads to statistically significant reductions not only in the total PDQ score but also in the intensity of pain, number of areas affected, and pain radiation. Furthermore, it makes it possible to reduce the dosage of concomitant medication.

  18. Mainstreaming the social sciences in conservation.

    PubMed

    Bennett, Nathan J; Roth, Robin; Klain, Sarah C; Chan, Kai M A; Clark, Douglas A; Cullman, Georgina; Epstein, Graham; Nelson, Michael Paul; Stedman, Richard; Teel, Tara L; Thomas, Rebecca E W; Wyborn, Carina; Curran, Deborah; Greenberg, Alison; Sandlos, John; Veríssimo, Diogo

    2017-02-01

    Despite broad recognition of the value of social sciences and increasingly vocal calls for better engagement with the human element of conservation, the conservation social sciences remain misunderstood and underutilized in practice. The conservation social sciences can provide unique and important contributions to society's understanding of the relationships between humans and nature and to improving conservation practice and outcomes. There are 4 barriers-ideological, institutional, knowledge, and capacity-to meaningful integration of the social sciences into conservation. We provide practical guidance on overcoming these barriers to mainstream the social sciences in conservation science, practice, and policy. Broadly, we recommend fostering knowledge on the scope and contributions of the social sciences to conservation, including social scientists from the inception of interdisciplinary research projects, incorporating social science research and insights during all stages of conservation planning and implementation, building social science capacity at all scales in conservation organizations and agencies, and promoting engagement with the social sciences in and through global conservation policy-influencing organizations. Conservation social scientists, too, need to be willing to engage with natural science knowledge and to communicate insights and recommendations clearly. We urge the conservation community to move beyond superficial engagement with the conservation social sciences. A more inclusive and integrative conservation science-one that includes the natural and social sciences-will enable more ecologically effective and socially just conservation. Better collaboration among social scientists, natural scientists, practitioners, and policy makers will facilitate a renewed and more robust conservation. Mainstreaming the conservation social sciences will facilitate the uptake of the full range of insights and contributions from these fields into

  19. Decentralizing conservation and diversifying livelihoods within Kanchenjunga Conservation Area, Nepal.

    PubMed

    Parker, Pete; Thapa, Brijesh; Jacob, Aerin

    2015-12-01

    To alleviate poverty and enhance conservation in resource dependent communities, managers must identify existing livelihood strategies and the associated factors that impede household access to livelihood assets. Researchers increasingly advocate reallocating management power from exclusionary central institutions to a decentralized system of management based on local and inclusive participation. However, it is yet to be shown if decentralizing conservation leads to diversified livelihoods within a protected area. The purpose of this study was to identify and assess factors affecting household livelihood diversification within Nepal's Kanchenjunga Conservation Area Project, the first protected area in Asia to decentralize conservation. We randomly surveyed 25% of Kanchenjunga households to assess household socioeconomic and demographic characteristics and access to livelihood assets. We used a cluster analysis with the ten most common income generating activities (both on- and off-farm) to group the strategies households use to diversify livelihoods, and a multinomial logistic regression to identify predictors of livelihood diversification. We found four distinct groups of household livelihood strategies with a range of diversification that directly corresponded to household income. The predictors of livelihood diversification were more related to pre-existing socioeconomic and demographic factors (e.g., more landholdings and livestock, fewer dependents, receiving remittances) than activities sponsored by decentralizing conservation (e.g., microcredit, training, education, interaction with project staff). Taken together, our findings indicate that without direct policies to target marginalized groups, decentralized conservation in Kanchenjunga will continue to exclude marginalized groups, limiting a household's ability to diversify their livelihood and perpetuating their dependence on natural resources. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. LAKE PONTCHARTRAIN ESTUARY CONSERVATION PLAN

    EPA Science Inventory

    The Nature Conservancy will conduct a series of a least four science expert workshops to develop a Site Conservation Plan for the Lake Pontchartrain Estuary and adjacent wetlands. The objective of the Site Conservation Plan is to identify conservation targets, threats or stresse...

  1. Optimized spatial priorities for biodiversity conservation in China: a systematic conservation planning perspective.

    PubMed

    Wu, Ruidong; Long, Yongcheng; Malanson, George P; Garber, Paul A; Zhang, Shuang; Li, Diqiang; Zhao, Peng; Wang, Longzhu; Duo, Hairui

    2014-01-01

    By addressing several key features overlooked in previous studies, i.e. human disturbance, integration of ecosystem- and species-level conservation features, and principles of complementarity and representativeness, we present the first national-scale systematic conservation planning for China to determine the optimized spatial priorities for biodiversity conservation. We compiled a spatial database on the distributions of ecosystem- and species-level conservation features, and modeled a human disturbance index (HDI) by aggregating information using several socioeconomic proxies. We ran Marxan with two scenarios (HDI-ignored and HDI-considered) to investigate the effects of human disturbance, and explored the geographic patterns of the optimized spatial conservation priorities. Compared to when HDI was ignored, the HDI-considered scenario resulted in (1) a marked reduction (∼9%) in the total HDI score and a slight increase (∼7%) in the total area of the portfolio of priority units, (2) a significant increase (∼43%) in the total irreplaceable area and (3) more irreplaceable units being identified in almost all environmental zones and highly-disturbed provinces. Thus the inclusion of human disturbance is essential for cost-effective priority-setting. Attention should be targeted to the areas that are characterized as moderately-disturbed, <2,000 m in altitude, and/or intermediately- to extremely-rugged in terrain to identify potentially important regions for implementing cost-effective conservation. We delineated 23 primary large-scale priority areas that are significant for conserving China's biodiversity, but those isolated priority units in disturbed regions are in more urgent need of conservation actions so as to prevent immediate and severe biodiversity loss. This study presents a spatially optimized national-scale portfolio of conservation priorities--effectively representing the overall biodiversity of China while minimizing conflicts with economic

  2. Optimized Spatial Priorities for Biodiversity Conservation in China: A Systematic Conservation Planning Perspective

    PubMed Central

    Wu, Ruidong; Long, Yongcheng; Malanson, George P.; Garber, Paul A.; Zhang, Shuang; Li, Diqiang; Zhao, Peng; Wang, Longzhu; Duo, Hairui

    2014-01-01

    By addressing several key features overlooked in previous studies, i.e. human disturbance, integration of ecosystem- and species-level conservation features, and principles of complementarity and representativeness, we present the first national-scale systematic conservation planning for China to determine the optimized spatial priorities for biodiversity conservation. We compiled a spatial database on the distributions of ecosystem- and species-level conservation features, and modeled a human disturbance index (HDI) by aggregating information using several socioeconomic proxies. We ran Marxan with two scenarios (HDI-ignored and HDI-considered) to investigate the effects of human disturbance, and explored the geographic patterns of the optimized spatial conservation priorities. Compared to when HDI was ignored, the HDI-considered scenario resulted in (1) a marked reduction (∼9%) in the total HDI score and a slight increase (∼7%) in the total area of the portfolio of priority units, (2) a significant increase (∼43%) in the total irreplaceable area and (3) more irreplaceable units being identified in almost all environmental zones and highly-disturbed provinces. Thus the inclusion of human disturbance is essential for cost-effective priority-setting. Attention should be targeted to the areas that are characterized as moderately-disturbed, <2,000 m in altitude, and/or intermediately- to extremely-rugged in terrain to identify potentially important regions for implementing cost-effective conservation. We delineated 23 primary large-scale priority areas that are significant for conserving China's biodiversity, but those isolated priority units in disturbed regions are in more urgent need of conservation actions so as to prevent immediate and severe biodiversity loss. This study presents a spatially optimized national-scale portfolio of conservation priorities – effectively representing the overall biodiversity of China while minimizing conflicts with economic

  3. Proton transfer from C-6 of uridine 5'-monophosphate catalyzed by orotidine 5'-monophosphate decarboxylase: formation and stability of a vinyl carbanion intermediate and the effect of a 5-fluoro substituent.

    PubMed

    Tsang, Wing-Yin; Wood, B McKay; Wong, Freeman M; Wu, Weiming; Gerlt, John A; Amyes, Tina L; Richard, John P

    2012-09-05

    The exchange for deuterium of the C-6 protons of uridine 5'-monophosphate (UMP) and 5-fluorouridine 5'-monophosphate (F-UMP) catalyzed by yeast orotidine 5'-monophosphate decarboxylase (ScOMPDC) at pD 6.5-9.3 and 25 °C was monitored by (1)H NMR spectroscopy. Deuterium exchange proceeds by proton transfer from C-6 of the bound nucleotide to the deprotonated side chain of Lys-93 to give the enzyme-bound vinyl carbanion. The pD-rate profiles for k(cat) give turnover numbers for deuterium exchange into enzyme-bound UMP and F-UMP of 1.2 × 10(-5) and 0.041 s(-1), respectively, so that the 5-fluoro substituent results in a 3400-fold increase in the first-order rate constant for deuterium exchange. The binding of UMP and F-UMP to ScOMPDC results in 0.5 and 1.4 unit decreases, respectively, in the pK(a) of the side chain of the catalytic base Lys-93, showing that these nucleotides bind preferentially to the deprotonated enzyme. We also report the first carbon acid pK(a) values for proton transfer from C-6 of uridine (pK(CH) = 28.8) and 5-fluorouridine (pK(CH) = 25.1) in aqueous solution. The stabilizing effects of the 5-fluoro substituent on C-6 carbanion formation in solution (5 kcal/mol) and at ScOMPDC (6 kcal/mol) are similar. The binding of UMP and F-UMP to ScOMPDC results in a greater than 5 × 10(9)-fold increase in the equilibrium constant for proton transfer from C-6, so that ScOMPDC stabilizes the bound vinyl carbanions, relative to the bound nucleotides, by at least 13 kcal/mol. The pD-rate profile for k(cat)/K(m) for deuterium exchange into F-UMP gives the intrinsic second-order rate constant for exchange catalyzed by the deprotonated enzyme as 2300 M(-1) s(-1). This was used to calculate a total rate acceleration for ScOMPDC-catalyzed deuterium exchange of 3 × 10(10) M(-1), which corresponds to a transition-state stabilization for deuterium exchange of 14 kcal/mol. We conclude that a large portion of the total transition-state stabilization for the

  4. 75 FR 1121 - Energy Conservation Program: Energy Conservation Standards for Certain Consumer Products...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-08

    ...The U.S. Department of Energy (DOE) is adopting amended energy conservation standards for commercial clothes washers (CCWs). DOE has determined that amended energy conservation standards for these types of equipment would result in significant conservation of energy, and are technologically feasible and economically justified.

  5. Synthesis and review: delivering on conservation promises: the challenges of managing and measuring conservation outcomes

    NASA Astrophysics Data System (ADS)

    Adams, Vanessa M.; Game, Edward T.; Bode, Michael

    2014-08-01

    Growing threats and limited resources have always been the financial realities of biodiversity conservation. As the conservation sector has matured, however, the accountability of conservation investments has become an increasingly debated topic, with two key topics being driven to the forefront of the discourse: understanding how to manage the risks associated with our conservation investments and demonstrating that our investments are making a difference through evidence-based analyses. A better understanding of the uncertainties associated with conservation decisions is a central component of managing risks to investments that is often neglected. This focus issue presents both theoretical and applied approaches to quantifying and managing risks. Furthermore, transparent and replicable approaches to measuring impacts of conservation investments are noticeably absent in many conservation programs globally. This focus issue contains state of the art conservation program impact evaluations that both demonstrate how these methods can be used to measure outcomes as well as directing future investments. This focus issue thus brings together current thinking and case studies that can provide a valuable resource for directing future conservation investments.

  6. Mistaken identity: activating conservative political identities induces "conservative" financial decisions.

    PubMed

    Morris, Michael W; Carranza, Erica; Fox, Craig R

    2008-11-01

    Four studies investigated whether activating a social identity can lead group members to choose options that are labeled in words associated with that identity. When political identities were made salient, Republicans (but not Democrats) became more likely to choose the gamble or investment option labeled "conservative." This shift did not occur in a condition in which the same options were unlabeled. Thus, the mechanism underlying the effect appears to be not activated identity-related values prioritizing low risk, but rather activated identity-related language (the group label "conservative"). Indeed, when political identities were salient, Republicans favored options labeled "conservative" regardless of whether the options were low or high risk. Finally, requiring participants to explain the label "conservative" before making their choice did not diminish the effect, which suggests that it does not merely reflect inattention to content or construct accessibility. We discuss the implications of these results for the literatures on identity, priming, choice, politics, and marketing.

  7. Maximizing species conservation in continental Ecuador: a case of systematic conservation planning for biodiverse regions

    PubMed Central

    Lessmann, Janeth; Muñoz, Jesús; Bonaccorso, Elisa

    2014-01-01

    Ecuador has the largest number of species by area worldwide, but also a low representation of species within its protected areas. Here, we applied systematic conservation planning to identify potential areas for conservation in continental Ecuador, with the aim of increasing the representation of terrestrial species diversity in the protected area network. We selected 809 terrestrial species (amphibians, birds, mammals, and plants), for which distributions were estimated via species distribution models (SDMs), using Maxent. For each species we established conservation goals based on conservation priorities, and estimated new potential protected areas using Marxan conservation planning software. For each selected area, we determined their conservation priority and feasibility of establishment, two important aspects in the decision-making processes. We found that according to our conservation goals, the current protected area network contains large conservation gaps. Potential areas for conservation almost double the surface area of currently protected areas. Most of the newly proposed areas are located in the Coast, a region with large conservation gaps and irreversible changes in land use. The most feasible areas for conservation were found in the Amazon and Andes regions, which encompass more undisturbed habitats, and already harbor most of the current reserves. Our study allows defining a viable strategy for preserving Ecuador's biodiversity, by combining SDMs, GIS-based decision-support software, and priority and feasibility assessments of the selected areas. This approach is useful for complementing protected area networks in countries with great biodiversity, insufficient biological information, and limited resources for conservation. PMID:25360277

  8. Creative Conservation Communication

    NASA Astrophysics Data System (ADS)

    Houston, Jason

    2015-04-01

    I am a fellow with the International League of Conservation photographers (iLCP) and have been focused on photographing conservation dynamics at the intersection of social and environmental issues for a decade. Subjects have included traditional concerns such as deforestation, water conservation, endangered species, and fisheries. However, I rarely make photographs of the traditional nature, wildlife, landscapes, or environmental atrocities that most people think of when they think about environmentalism. Instead, I photograph people and how they live on the planet, as I believe passionately that without also considering social and cultural concerns, we will not be able to effectively and sustainably do conservation work or achieve positive environmental change. My presentation will share recent photography projects on forest conservation in Indonesian Borneo and fisheries management in Central America where I used a 'stakeholder profile-based' process to broadly survey the complexity of the issues while also making personal connections for these projects' diverse audiences. Through these case studies I will explore the opportunities and challenges of combining the authenticity, accuracy, and scientific validity of journalistic and documentary work with the emotional impact of the conventions of art and storytelling.

  9. Optimum allocation of conservation funds and choice of conservation programs for a set of African cattle breeds

    PubMed Central

    Reist-Marti, Sabine B; Abdulai, Awudu; Simianer, Henner

    2006-01-01

    Although funds for livestock conservation are limited there is little known about the optimal allocation of conservation funds. A new algorithm was used to allocate Mio US$ 1, 2, 3, 5 or unlimited funds, discounted over 50 years, on 23 African cattle breeds conserved with four different possible conservation programs. Additionally, Mio US$ 1 was preferably allocated to breeds with special traits. The conceptional in situ conservation programs strongly involve breeders and give them part of the responsibility for the conservation of the breed. Therefore, the pure in situ conservation was more efficient than cryoconservation or combined in situ and cryoconservation. The average annual discounted conservation cost for a breed can be as low as US$ 1000 to US$ 4400 depending on the design of the conservation program and the economic situation of the country of conservation. The choice of the breeds and the optimal conservation program and the amount of money allocated to each breed depend on many factors such as the amount of funds available, the conservation potential of each breed, the effects of the conservation program as well as its cost. With Mio US$ 1, 64% of the present diversity could be maintained over 50 years, which is 13% more than would be maintained if no conservation measures were implemented. Special traits could be conserved with a rather small amount of the total funds. Diversity can not be conserved completely, not even with unlimited funds. A maximum of 92% of the present diversity could be conserved with Mio US$ 10, leaving 8% of the diversity to unpredictable happenings. The suggested algorithm proved to be useful for optimal allocation of conservation funds. It allocated the funds optimally among breeds by identifying the most suited conservation program for each breed, also accounting for differences in currency exchange rates between the different countries. PMID:16451794

  10. Waterfowl populations of conservation concern: learning from diverse challenges, models, and conservation strategies

    USGS Publications Warehouse

    Austin, Jane E.; Slattery, Stuart; Clark, Robert G.

    2014-01-01

    There are 30 threatened or endangered species of waterfowl worldwide, and several sub-populations are also threatened. Some of these species occur in North America, and others there are also of conservation concern due to declining population trends and their importance to hunters. Here we review conservation initiatives being undertaken for several of these latter species, along with conservation measures in place in Europe, to seek common themes and approaches that could be useful in developing broad conservation guidelines. While focal species may vary in their life histories, population threats and geopolitical context, most conservation efforts have used a systematic approach to understand factors limiting populations and o identify possible management or policy actions. This approach generally includes a priori identification of plausible hypotheses about population declines or status, incorporation of hypotheses into conceptual or quantitative planning models, and the use of some form of structured decision making and adaptive management to develop and implement conservation actions in the face of many uncertainties. A climate of collaboration among jurisdictions sharing these birds is important to the success of a conservation or management programme. The structured conservation approach exemplified herein provides an opportunity to involve stakeholders at all planning stages, allows for all views to be examined and incorporated into model structures, and yields a format for improved communication, cooperation and learning, which may ultimately be one of the greatest benefits of this strategy.

  11. 75 FR 57059 - Montana Department of Natural Resources and Conservation Final Habitat Conservation Plan and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R6-ES-2010-N175; 61130-1115-0000 F2] Montana Department of Natural Resources and Conservation Final Habitat Conservation Plan and Final... Department of Natural Resources and Conservation (DNRC) a Final Habitat Conservation Plan (HCP) and prepared...

  12. Evaluating local benefits from conservation in Nepal's Annapurna Conservation Area.

    PubMed

    Spiteri, Arian; Nepal, Sanjay K

    2008-09-01

    Protected areas are integral to the global effort to conserve biodiversity, and, over the past two decades, protected area managers have begun to recognize that conservation objectives are next to impossible to achieve without considering the needs and concerns of local communities. Incentive-based programs (IBPs) have become a favored approach to protected area management, geared at fostering local stewardship by delivering benefits tied to conservation to local people. Effective IBPs require benefits to accrue to and be recognized by those experiencing the greatest consequences as a result of the protected area, and those likely to continue extractive activities if their livelihood needs are compromised. This research examines dispersal of IBP benefits, as perceived by local residents in Nepal's Annapurna Conservation Area. Results reported here are based on questionnaire interviews with 188 households conducted between September and December 2004. Results indicate that local residents primarily identify benefits from social development activities, provisions for resource extraction, and economic opportunities. Overall, benefits have been dispersed equally to households in villages on and off the main tourist route, and regardless of a household's participation in tourism. However, benefits are not effectively targeted to poorer residents, those highly dependent on natural resources, and those experiencing the most crop damage and livestock loss from protected wildlife. This article provides several suggestions for improving the delivery of conservation incentives.

  13. Trehalose acts as a uridine 5'-diphosphoglucose-competitive inhibitor of trehalose 6-phosphate synthase in Corynebacterium glutamicum.

    PubMed

    Oide, Shinichi; Inui, Masayuki

    2017-12-01

    Trehalose is a compatible solute widely distributed in nature. The most prevalent pathway for its synthesis starts from condensation of glucose 6-phosphate (Glc6P) and uridine 5'-diphosphoglucose (UDP-Glc) catalyzed by trehalose 6-phosphate synthase (TPS). A previous laboratory evolution experiment with the bacterium Corynebacterium glutamicum generated strains adapted to supraoptimal temperatures, and the R328H substitution of the TPS encoded by otsA was shown to be associated with thermotolerance acquired by the evolved strains. In this study, we found that the OtsA:R328H substitution promotes both intra- and extracellular trehalose accumulation and demonstrated that build-up of intracellular trehalose accounts for the OtsA R 328H -dependent thermotolerance, using the mycobacterial trehalose-specific transporter. Counterintuitively, characterization of the recombinant OtsA proteins revealed that the mutation downshifts the temperature optimum of OtsA. A search for the molecular basis of OtsA R 328H -dependent enhancement of trehalose synthesis led to the unexpected findings that trehalose is an effective inhibitor of OtsA and that OtsA R 328H is highly tolerant to the trehalose-mediated inhibition. The only available report on such feedback regulation of TPS is for the silk moth from over 50 years ago [Murphy TA and Wyatt GR (1965) J Biol Chem 240, 1500-1508]. While trehalose acts as a Glc6P-competitive inhibitor in the silk moth, the disaccharide was found to inhibit OtsA in a UDP-Glc-competitive manner in C. glutamicum, suggesting independent origins of the negative feedback regulations found for the two species. We showed that overexpression of the wild-type OtsA counteracts the trehalose-dependent regulation and restores the evolved strain-like phenotype to the isogenic wild-type otsA revertant, demonstrating that thermotolerance conferred by OtsA R 328H is attributable to its feedback-resistant property. © 2017 Federation of European Biochemical

  14. Prairie Conservation in Canada: The Prairie Conservation Action Plan Experience

    Treesearch

    Dean Nernberg; David Ingstrup

    2005-01-01

    In Canada, grassland conservation has been mobilized and directed through the development of Prairie Conservation Action Plans and Action Plan Committees in the three prairie provinces of Alberta (45 partner agencies and organizations), Saskatchewan (26 partners), and Manitoba (26 partners). In Alberta, 43 percent of the native prairie remains; in Saskatchewan and...

  15. Beyond protection: Expanding "conservation opportunity" to redefine conservation planning in the 21st century.

    PubMed

    Liberati, Marjorie R; Rittenhouse, Chadwick D; Vokoun, Jason C

    2016-12-01

    The protected lands estate increased dramatically during the 20th century and forms the backbone of current fisheries and wildlife conservation in North America. However, there is increasing evidence that modern conservation goals cannot be achieved by only focusing on adding new acreage, particularly with opportunistic protection. In the 21st century, flexibility and adaptability of conservation options can be accomplished by expanding the vocabulary of conservation planning beyond protection. We suggest a conceptual framework that considers suites of objectives to translate the broad goal of "conservation" into multiple implementation-specific objectives. These objectives form the "PCRM-PI" approach: protect, connect, restore, manage, partner, and inform. We use a case study to illustrate the limitations of protection-centric planning and how expanding the definition of conservation opportunity can help planners do more on the landscape. We suggest that the PCRM-PI approach with implementation-specific objectives is an effective way to bridge planning-implementation gaps and translate broad, landscape-level conservation goals into implementable actions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Conservation caring: measuring the influence of zoo visitors' connection to wildlife on pro-conservation behaviors.

    PubMed

    Skibins, Jeffrey C; Powell, Robert B

    2013-01-01

    Zoos in the 21st century are striving to make effective contributions to conservation. Although zoos are extremely popular and host over 600 million visitors worldwide, one challenge zoos face is how to effectively engage visitors and raise awareness and action for conservation. To this end, zoos commonly rely on charismatic megafauna, which have been shown to elicit a connection with zoo visitors. However, little is known about how to measure a connection to a species or how this connection may influence conservation behaviors. This study had two sequential objectives. The first was to develop a scale to measure visitors' connection to a species (Conservation Caring). The second was to investigate the relationship of Conservation Caring to pro-conservation behaviors, following a zoo experience. Pre- (n = 411) and post-visit (n = 452) responses were collected from three sites in order to assess the reliability and validity of a scale to measure Conservation Caring. Structural equation modeling was used to explore the relationship between Conservation Caring and pro-conservation behaviors. Conservation Caring was deemed a valid and reliable scale and was a strong predictor of species oriented behaviors (β = 0.62), for example, "adopting" an animal, but a weak predictor for biodiversity oriented behaviors (β = 0.07), for example, supporting sustainability policies. Results support the role zoos can play in fostering a connection to wildlife and stimulating pro-conservation behaviors. Additionally, visitors connected to a wide array of animals. On the basis of these results, zoos may recruit a wider assemblage of species as potential flagships. © 2013 Wiley Periodicals, Inc.

  17. 76 FR 57897 - Energy Conservation Program: Energy Conservation Standards for Certain External Power Supplies

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... Energy Conservation Program: Energy Conservation Standards for Certain External Power Supplies AGENCY... external power supplies used in specific applications from certain energy conservation standards prescribed... external power supplies used either in security or life safety alarms or surveillance system components...

  18. Credibility and advocacy in conservation science.

    PubMed

    Horton, Cristi C; Peterson, Tarla Rai; Banerjee, Paulami; Peterson, Markus J

    2016-02-01

    Conservation policy sits at the nexus of natural science and politics. On the one hand, conservation scientists strive to maintain scientific credibility by emphasizing that their research findings are the result of disinterested observations of reality. On the other hand, conservation scientists are committed to conservation even if they do not advocate a particular policy. The professional conservation literature offers guidance on negotiating the relationship between scientific objectivity and political advocacy without damaging conservation science's credibility. The value of this guidance, however, may be restricted by limited recognition of credibility's multidimensionality and emergent nature: it emerges through perceptions of expertise, goodwill, and trustworthiness. We used content analysis of the literature to determine how credibility is framed in conservation science as it relates to apparent contradictions between science and advocacy. Credibility typically was framed as a static entity lacking dimensionality. Authors identified expertise or trustworthiness as important, but rarely mentioned goodwill. They usually did not identify expertise, goodwill, or trustworthiness as dimensions of credibility or recognize interactions among these 3 dimensions of credibility. This oversimplification may limit the ability of conservation scientists to contribute to biodiversity conservation. Accounting for the emergent quality and multidimensionality of credibility should enable conservation scientists to advance biodiversity conservation more effectively. © 2015 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  19. The Data Conservancy

    NASA Astrophysics Data System (ADS)

    Choudhury, S.; Duerr, R. E.

    2009-12-01

    NSF's Sustainable Digital Data Preservation and Access Network Partners program is an ambitious attempt to integrate a wide variety of expertise and infrastructure into a network for providing "reliable digital preservation, access, integration, and analysis capabilities for science." One of the first two DataNet award recipients, the Data Conservancy, is itself a network of widely diverse partners led by the libraries at the Johns Hopkins University. The Data Conservancy is built on existing exemplar scientific projects, communities, and virtual organizations that have deep engagement with their user communities, and extensive experience with large-scale distributed system development. Data Conservancy members embrace a shared vision that data curation is not an end, but rather a means to collect, organize, validate, and preserve data needed to address the grand research challenges that face society. Data Conservancy members holdings encompass the entire range of earth, life, and space science data. New to the Data Conservancy is the concept that University libraries will be part of the distributed network of data centers and that data science will become a path in the library and information science curricula. As noted by Winston Tabb (JHU Dean of Libraries) "Data Centers are the new library stacks."

  20. Focusing ecological research for conservation.

    PubMed

    Cristescu, Bogdan; Boyce, Mark S

    2013-11-01

    Ecologists are increasingly actively involved in conservation. We identify five key topics from a broad sweep of ecology that merit research attention to meet conservation needs. We examine questions from landscape ecology, behavioral ecology, ecosystem dynamics, community ecology, and nutrient cycling related to key topics. Based on literature review and publication trend assessment, consultation with colleagues, and roundtable discussions at the 24th International Congress for Conservation Biology, focused research on the following topics could benefit conservation while advancing ecological understanding: 1. Carbon sequestration, requiring increased linkages to biodiversity conservation; 2. Ecological invasiveness, challenging our ability to find solutions to ecological aliens; 3. Individual variation, having applications in the conservation of rare species; 4. Movement of organisms, integrating ecological processes across landscapes and scales and addressing habitat fragmentation; and 5. Trophic-level interactions, driving ecological dynamics at the ecosystem-level. Addressing these will require cross-disciplinary research under the overarching framework of conservation ecology.

  1. Structure-guided discovery of the metabolite carboxy-SAM that modulates tRNA function.

    PubMed

    Kim, Jungwook; Xiao, Hui; Bonanno, Jeffrey B; Kalyanaraman, Chakrapani; Brown, Shoshana; Tang, Xiangying; Al-Obaidi, Nawar F; Patskovsky, Yury; Babbitt, Patricia C; Jacobson, Matthew P; Lee, Young-Sam; Almo, Steven C

    2013-06-06

    The identification of novel metabolites and the characterization of their biological functions are major challenges in biology. X-ray crystallography can reveal unanticipated ligands that persist through purification and crystallization. These adventitious protein-ligand complexes provide insights into new activities, pathways and regulatory mechanisms. We describe a new metabolite, carboxy-S-adenosyl-l-methionine (Cx-SAM), its biosynthetic pathway and its role in transfer RNA modification. The structure of CmoA, a member of the SAM-dependent methyltransferase superfamily, revealed a ligand consistent with Cx-SAM in the catalytic site. Mechanistic analyses showed an unprecedented role for prephenate as the carboxyl donor and the involvement of a unique ylide intermediate as the carboxyl acceptor in the CmoA-mediated conversion of SAM to Cx-SAM. A second member of the SAM-dependent methyltransferase superfamily, CmoB, recognizes Cx-SAM and acts as a carboxymethyltransferase to convert 5-hydroxyuridine into 5-oxyacetyl uridine at the wobble position of multiple tRNAs in Gram-negative bacteria, resulting in expanded codon-recognition properties. CmoA and CmoB represent the first documented synthase and transferase for Cx-SAM. These findings reveal new functional diversity in the SAM-dependent methyltransferase superfamily and expand the metabolic and biological contributions of SAM-based biochemistry. These discoveries highlight the value of structural genomics approaches in identifying ligands within the context of their physiologically relevant macromolecular binding partners, and in revealing their functions.

  2. 2-Thiouracil deprived of thiocarbonyl function preferentially base pairs with guanine rather than adenine in RNA and DNA duplexes

    PubMed Central

    Sochacka, Elzbieta; Szczepanowski, Roman H.; Cypryk, Marek; Sobczak, Milena; Janicka, Magdalena; Kraszewska, Karina; Bartos, Paulina; Chwialkowska, Anna; Nawrot, Barbara

    2015-01-01

    2-Thiouracil-containing nucleosides are essential modified units of natural and synthetic nucleic acids. In particular, the 5-substituted-2-thiouridines (S2Us) present in tRNA play an important role in tuning the translation process through codon–anticodon interactions. The enhanced thermodynamic stability of S2U-containing RNA duplexes and the preferred S2U-A versus S2U-G base pairing are appreciated characteristics of S2U-modified molecular probes. Recently, we have demonstrated that 2-thiouridine (alone or within an RNA chain) is predominantly transformed under oxidative stress conditions to 4-pyrimidinone riboside (H2U) and not to uridine. Due to the important biological functions and various biotechnological applications for sulfur-containing nucleic acids, we compared the thermodynamic stabilities of duplexes containing desulfured products with those of 2-thiouracil-modified RNA and DNA duplexes. Differential scanning calorimetry experiments and theoretical calculations demonstrate that upon 2-thiouracil desulfuration to 4-pyrimidinone, the preferred base pairing of S2U with adenosine is lost, with preferred base pairing with guanosine observed instead. Therefore, biological processes and in vitro assays in which oxidative desulfuration of 2-thiouracil-containing components occurs may be altered. Moreover, we propose that the H2U-G base pair is a suitable model for investigation of the preferred recognition of 3′-G-ending versus A-ending codons by tRNA wobble nucleosides, which may adopt a 4-pyrimidinone-type structural motif. PMID:25690900

  3. Elp3 and Dph3 of Schizosaccharomyces pombe mediate cellular stress responses through tRNALysUUU modifications.

    PubMed

    Villahermosa, Desirée; Fleck, Oliver

    2017-08-03

    Efficient protein synthesis in eukaryotes requires diphthamide modification of translation elongation factor eEF2 and wobble uridine modifications of tRNAs. In higher eukaryotes, these processes are important for preventing neurological and developmental defects and cancer. In this study, we used Schizosaccharomyces pombe as a model to analyse mutants defective in eEF2 modification (dph1Δ), in tRNA modifications (elp3Δ), or both (dph3Δ) for sensitivity to cytotoxic agents and thermal stress. The dph3Δ and elp3Δ mutants were sensitive to a range of drugs and had growth defects at low temperature. dph3Δ was epistatic with dph1Δ for sensitivity to hydroxyurea and methyl methanesulfonate, and with elp3Δ for methyl methanesulfonate and growth at 16 °C. The dph1Δ and dph3Δ deletions rescued growth defects of elp3Δ in response to thiabendazole and at 37 °C. Elevated tRNA Lys UUU levels suppressed the elp3Δ phenotypes and some of the dph3Δ phenotypes, indicating that lack of tRNA Lys UUU modifications were responsible. Furthermore, we found positive genetic interactions of elp3Δ and dph3Δ with sty1Δ and atf1Δ, indicating that Elp3/Dph3-dependent tRNA modifications are important for efficient biosynthesis of key factors required for accurate responses to cytotoxic stress conditions.

  4. Do Cyclosporine A, an IL-1 Receptor Antagonist, Uridine Triphosphate, Rebamipide, and/or Bimatoprost Regulate Human Meibomian Gland Epithelial Cells?

    PubMed Central

    Kam, Wendy R.; Liu, Yang; Ding, Juan; Sullivan, David A.

    2016-01-01

    Purpose Researchers have hypothesized that treatment with cyclosporine A (CyA), interleukin-1 receptor antagonists (IL-1RA; e.g., anakinra), P2Y2 receptor agonists (e.g., uridine triphosphate; UTP), and rebamipide may alleviate human meibomian gland dysfunction (MGD) and/or dry eye disease. Investigators have also proposed that prostaglandin analogues (e.g., bimatoprost) may induce MGD. Our goal was to determine whether these compounds directly influence human meibomian gland epithelial cell (HMGEC) function. Methods Multiple concentrations of each compound were tested for effects on immortalized (I) HMGEC morphology and survival. Nontoxic dosages were used for our studies. Immortalized HMGEC were cultured in the presence of vehicle, CyA, IL-1RA, UTP, rebamipide, or bimatoprost for up to 6 days in various media. Experiments included positive controls for proliferation (epidermal growth factor and bovine pituitary extract), differentiation (azithromycin), and signaling pathway activation (insulin-like growth factor 1). Cells were analyzed for neutral lipid staining, lysosome accumulation, lipid composition, and phosphatidylinositol-3-kinase/Akt (AKT), phosphorylation. Results Our findings demonstrate that CyA, IL-1RA, UTP, rebamipide, and bimatoprost had no effect on the proliferation; neutral lipid content; lysosome number; or levels of free cholesterol, triglycerides, or phospholipids in IHMGECs. Cylosporine A, IL-1RA, rebamipide, and bimatoprost significantly reduced the phosphorylation of AKT, as compared to control. Of interest, tested doses of CyA above 8 nM killed the IHMGECs. Conclusions Our results show that CyA, IL-1RA, UTP, rebamipide, and bimatoprost do not influence the proliferation or differentiation of IHMGEC. However, with the exception of UTP, these compounds do decrease the activity of the AKT signaling pathway, which is known to promote cell survival. PMID:27552406

  5. Doping test results dependent on genotype of uridine diphospho-glucuronosyl transferase 2B17, the major enzyme for testosterone glucuronidation.

    PubMed

    Schulze, Jenny Jakobsson; Lundmark, Jonas; Garle, Mats; Skilving, Ilona; Ekström, Lena; Rane, Anders

    2008-07-01

    Testosterone abuse is conventionally assessed by the urinary testosterone/epitestosterone (T/E) ratio, levels above 4.0 being considered suspicious. The large variation in testosterone glucuronide (TG) excretion and its strong association with a deletion polymorphism in the uridine diphospho-glucuronosyl transferase (UGT) 2B17 gene challenge the accuracy of the T/E ratio test. Our objective was to investigate whether genotype-based cutoff values will improve the sensitivity and specificity of the test. This was an open three-armed comparative study. A total of 55 healthy male volunteers with either two, one, or no allele [insertion/insertion, insertion/deletion, or deletion/deletion (del/del)] of the UGT2B17 gene was included in the study. A single im dose of 500 mg testosterone enanthate was administered. Urinary excretion of TG after dose and the T/E ratio during 15 d were calculated. The degree and rate of increase in the TG excretion rate were highly dependent on the UGT2B17 genotype with a 20-fold higher average maximum increase in the insertion/insertion group compared with the del/del group. Of the del/del subjects, 40% never reached the T/E ratio of 4.0 on any of the 15 d after the dose. When differentiated cutoff levels for the del/del (1.0) and the other genotypes (6.0) were applied, the sensitivity increased substantially for the del/del group, and false positives in the other genotypes were eliminated. Consideration of the genetic variation in disposition of androgens will improve the sensitivity and specificity of the testosterone doping test. This is of interest not only for combating androgen doping in sports, but also for detecting and preventing androgen abuse in society.

  6. Crowdfunding biodiversity conservation.

    PubMed

    Gallo-Cajiao, E; Archibald, C; Friedman, R; Steven, R; Fuller, R A; Game, E T; Morrison, T H; Ritchie, E G

    2018-05-26

    Raising funds is critical for conserving biodiversity and hence so too is scrutinizing emerging financial mechanisms that might help achieve this goal. In this context, anecdotal evidence indicates crowdfunding is being used to support a variety of activities needed for biodiversity conservation, yet its magnitude and allocation remain largely unknown. We conducted a global analysis to help address this knowledge gap, based on empirical data from conservation-focused projects extracted from crowdfunding platforms. For each project, we determined the funds raised, date, country of implementation, proponent characteristics, activity type, biodiversity realm, and target taxa. We identified 72 relevant platforms and 577 conservation-focused projects that have raised US$4 790 634 since 2009. Whilst proponents were based in 38 countries, projects were delivered across 80 countries, indicating a potential mechanism of resource mobilization. Proponents were from non-governmental organizations (35%), universities (30%), or were freelancers (26%). Most projects were for research (40%), persuasion (31%), and on-ground actions (21%). Projects have focused primarily on species (57.7%) and terrestrial ecosystems (20.3%), and less on marine (8.8%) and freshwater ecosystems (3.6%). Projects have focused on 208 species, including a disproportionate number of threatened bird and mammal species. Crowdfunding for biodiversity conservation has now become a global phenomenon and presents signals for potential expansion, despite possible pitfalls. Opportunities arise from its spatial amplifying effect, steady increase over time, inclusion of Cinderella species, adoption by multiple actors, and funding of a range of activities beyond research. Our study paves the way for further research on key questions, such as campaign success rates, effectiveness, and drivers of adoption. Even though the capital input of crowdfunding so far has been modest compared to other conservation finance

  7. Tissue-specific DNA methylation is conserved across human, mouse, and rat, and driven by primary sequence conservation.

    PubMed

    Zhou, Jia; Sears, Renee L; Xing, Xiaoyun; Zhang, Bo; Li, Daofeng; Rockweiler, Nicole B; Jang, Hyo Sik; Choudhary, Mayank N K; Lee, Hyung Joo; Lowdon, Rebecca F; Arand, Jason; Tabers, Brianne; Gu, C Charles; Cicero, Theodore J; Wang, Ting

    2017-09-12

    Uncovering mechanisms of epigenome evolution is an essential step towards understanding the evolution of different cellular phenotypes. While studies have confirmed DNA methylation as a conserved epigenetic mechanism in mammalian development, little is known about the conservation of tissue-specific genome-wide DNA methylation patterns. Using a comparative epigenomics approach, we identified and compared the tissue-specific DNA methylation patterns of rat against those of mouse and human across three shared tissue types. We confirmed that tissue-specific differentially methylated regions are strongly associated with tissue-specific regulatory elements. Comparisons between species revealed that at a minimum 11-37% of tissue-specific DNA methylation patterns are conserved, a phenomenon that we define as epigenetic conservation. Conserved DNA methylation is accompanied by conservation of other epigenetic marks including histone modifications. Although a significant amount of locus-specific methylation is epigenetically conserved, the majority of tissue-specific DNA methylation is not conserved across the species and tissue types that we investigated. Examination of the genetic underpinning of epigenetic conservation suggests that primary sequence conservation is a driving force behind epigenetic conservation. In contrast, evolutionary dynamics of tissue-specific DNA methylation are best explained by the maintenance or turnover of binding sites for important transcription factors. Our study extends the limited literature of comparative epigenomics and suggests a new paradigm for epigenetic conservation without genetic conservation through analysis of transcription factor binding sites.

  8. Conservation endocrinology

    USGS Publications Warehouse

    McCormick, Stephen; Romero, L. Michael

    2017-01-01

    Endocrinologists can make significant contributions to conservation biology by helping to understand the mechanisms by which organisms cope with changing environments. Field endocrine techniques have advanced rapidly in recent years and can provide substantial information on the growth, stress, and reproductive status of individual animals, thereby providing insight into current and future responses of populations to changes in the environment. Environmental stressors and reproductive status can be detected nonlethally by measuring a number of endocrine-related endpoints, including steroids in plasma, living and nonliving tissue, urine, and feces. Information on the environmental or endocrine requirements of individual species for normal growth, development, and reproduction will provide critical information for species and ecosystem conservation. For many taxa, basic information on endocrinology is lacking, and advances in conservation endocrinology will require approaches that are both “basic” and “applied” and include integration of laboratory and field approaches.

  9. Wobbly Corner: Magnetism

    ERIC Educational Resources Information Center

    Corbett, Lisa; Maklad, Rania; Dunne, Mick; Grace, Pierre

    2014-01-01

    During a final seminar with BA year 4 science specialist trainee teachers, the authors posed a question about the difficulties associated with understanding magnetism. The ensuing discussion focused on a number of concerns commonly identified by students, which may also be of interest to classroom teachers teaching magnetism. Issues raised…

  10. ATTRIBUTES OF AESTHETIC QUALITY USED BY TEXTILE CONSERVATORS IN EVALUATING CONSERVATION INTERVENTIONS ON MUSEUM COSTUMES.

    PubMed

    Nilsson, Johanna; Axelsson, Östen

    2015-08-01

    Aesthetic quality is central to textile conservators when evaluating a conservation method. However, the literature on textile conservation chiefly focuses on physical properties, and little is known about what factors determine aesthetic quality according to textile conservators. The latter was explored through two experiments. Experiment 1 explored the underlying attributes of aesthetic quality of textile conservation interventions. Experiment 2 explored the relationships between these attributes and how well they predicted aesthetic quality. Rank-order correlation analyses revealed two latent factors called Coherence and Completeness. Ordinal regression analysis revealed that Coherence was the most important predictor of aesthetic quality. This means that a successful conservation intervention is visually well-integrated with the textile item in terms of the material and method.

  11. Hydrology and Conservation Ecology

    NASA Astrophysics Data System (ADS)

    Narayanan, M.

    2006-12-01

    Responses to change in the behavior of ecological systems are largely governed by interactions at different levels. Research is essential and is to be necessarily designed to gain insights into various interactions at the community level. Sustainable resource management is only possible if conservation of biodiversity can be accomplished by properly using the knowledge discovered. It is well known that the United States Department of Agriculture provides technical information, resources, and data necessary to assist the researchers in addressing their conservation needs. Conservation aims to protect, preserve and conserve the earth's natural resources. These include, but not limited to the conservation of soil, water, minerals, air, plants and all living beings. The United States Department of Agriculture also encourages farmers and ranchers to voluntarily address threats to soil and water. Protection of wetlands and wildlife habitat has been on the radar screen of conservation experts for a very long time. The main objective has always been to help farmers and landowners conform and comply with federal and state environmental laws. During the implementation phase, farmers should be encouraged to make beneficial, cost-effective changes to methods of irrigation systems. In some cases, the hydrologic regime of the project area can be thought of as principally an issue of river flow regimes for floodplain forests. In this presentation, the author tries to focus on the impact of hydrology and conservation ecology on global warming. He also discusses the impact of hydrology and conservation ecology global air concerns such as greenhouse gas concentrations in the atmosphere. References: Chow, V. T, D. R. Maidment, and L. W. Mays. 1988. Applied Hydrology. McGraw-Hill, Inc. U.S. Soil Conservation Service. Technical Release 55: Urban Hydrology for Small Watersheds. USDA (U.S. Department of Agriculture). June 1986. Lehner, B. and P. Döll (2004). Development and validation

  12. Resource Conservation Glossary.

    ERIC Educational Resources Information Center

    Soil Conservation Society of America, Ankeny, IA.

    This glossary is a composite of terms selected from 13 technologies, and is the expanded revision of the original 1952 edition of "The Soil and Water Conservation Glossary." The terms were selected from these areas: agronomy, biology, conservation, ecology, economics, engineering, forestry, geology, hydrology, range, recreation, soils, and…

  13. 5-fluorouracil Toxicity Mechanism Determination in Human Keratinocytes: in vitro Study on HaCaT Cell Line.

    PubMed

    Hartinger, Jan; Veselý, Pavel; Šíma, Martin; Netíková, Irena; Matoušková, Eva; Petruželka, Luboš

    5-fluorouracil (5-FU) and capecitabine therapy is often accompanied by palmar-plantar erythrodysesthesia (PPE) which is manifestation of 5-FU toxicity in keratinocytes. The main mechanisms of 5-FU action are thymidylate synthase (TS) inhibition which can be abrogated by thymidine and strengthened by calciumfolinate (CF) and incorporation of fluorouridinetriphosphate into RNA which can be abrogated by uridine. For proper PPE treatment 5-FU mechanism of action in keratinocytes needs to be elucidated. We used the 5-FU toxicity modulators uridine, thymidine and CF to discover the mechanism of 5-FU action in human keratinocyte cell line HaCaT. To measure the cellular viability, we used MTT test and RTCA test. CF did not augment 5-FU toxicity and 5-FU toxicity was weakened by uridine. Therefore, the primary mechanism of 5-FU toxicity in keratinocytes is 5-FU incorporation into RNA. The uridine protective effect cannot fully develop in the presence of CF. Thymidine addition to 5-FU and uridine treated cells not only prevents the toxicity-augmenting CF effect but it also prolongs the 5-FU treated cells survival in comparison to uridine only. Therefore, it can be assumed that in the presence of uridine the 5-FU toxicity mechanism is switched from RNA incorporation to TS inhibition. Although particular 5-FU toxicity mechanisms were previously described in various cell types, this is the first time when various combinations of pyrimidine nucleosides and CF were used for 5-FU toxicity mechanism elucidation in human keratinocytes. We suggest that for PPE treatment ointment containing uridine and thymidine should be further clinically tested.

  14. 76 FR 56126 - Energy Conservation Program: Treatment of “Smart” Appliances in Energy Conservation Standards and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-12

    ...'s energy conservation standards, as well as in test procedures used to demonstrate compliance with...'' appliances in the development of DOE's energy conservation standards, as well as in test procedures used to... Conservation Program: Treatment of ``Smart'' Appliances in Energy Conservation Standards and Test Procedures...

  15. 75 FR 17036 - Energy Conservation Program: Energy Conservation Standards for Small Electric Motors; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... Conservation Program: Energy Conservation Standards for Small Electric Motors; Correction AGENCY: Office of... standards for small electric motors, which was published on March 9, 2010. In that final rule, the U.S... titled ``Energy Conservation Standards for Small Electric Motors.'' 75 FR 10874. Since the publication of...

  16. Examining marginalized communities and local conservation institutions: the case of Nepal's Annapurna Conservation Area.

    PubMed

    Dahal, Smriti; Nepal, Sanjay K; Schuett, Michael A

    2014-01-01

    In developing countries, participatory conservation initiatives have been criticized for many reasons, mainly for excluding marginalized groups which have led to unequal benefits. Using concepts from the literature on participation, conservation, and political ecology, this research explored the participation of marginal groups, i.e., poor, women, lower caste, and landless, in management institutions in Nepal's Annapurna Conservation Area. Field work for this research was conducted through the use of interviews and participant observation during August-October 2010. Results show that although marginal groups were involved in local management institutions, their representation was minimal and had not led to meaningful participation or empowerment to influence the decisions being made in conservation and development programs. Our study findings indicate that the involvement of marginal groups in local initiatives is complex and influenced by several factors. The study concludes that the Annapurna Conservation Area Project needs to re-orient its conservation projects by adopting a more inclusive form of participation and move beyond the quota system.

  17. Examining Marginalized Communities and Local Conservation Institutions: The Case of Nepal's Annapurna Conservation Area

    NASA Astrophysics Data System (ADS)

    Dahal, Smriti; Nepal, Sanjay K.; Schuett, Michael A.

    2014-01-01

    In developing countries, participatory conservation initiatives have been criticized for many reasons, mainly for excluding marginalized groups which have led to unequal benefits. Using concepts from the literature on participation, conservation, and political ecology, this research explored the participation of marginal groups, i.e., poor, women, lower caste, and landless, in management institutions in Nepal's Annapurna Conservation Area. Field work for this research was conducted through the use of interviews and participant observation during August-October 2010. Results show that although marginal groups were involved in local management institutions, their representation was minimal and had not led to meaningful participation or empowerment to influence the decisions being made in conservation and development programs. Our study findings indicate that the involvement of marginal groups in local initiatives is complex and influenced by several factors. The study concludes that the Annapurna Conservation Area Project needs to re-orient its conservation projects by adopting a more inclusive form of participation and move beyond the quota system.

  18. 77 FR 59712 - Energy Conservation Program: Energy Conservation Standards for Dishwashers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... DEPARTMENT OF ENERGY 10 CFR Parts 429 and 430 [Docket Number EERE-2011-BT-STD-0060] RIN 1904-AC64 Energy Conservation Program: Energy Conservation Standards for Dishwashers AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION: Notice of effective date and compliance dates...

  19. Credibility and advocacy in conservation science

    PubMed Central

    Horton, Cristi C.; Peterson, Tarla Rai; Banerjee, Paulami

    2015-01-01

    Abstract Conservation policy sits at the nexus of natural science and politics. On the one hand, conservation scientists strive to maintain scientific credibility by emphasizing that their research findings are the result of disinterested observations of reality. On the other hand, conservation scientists are committed to conservation even if they do not advocate a particular policy. The professional conservation literature offers guidance on negotiating the relationship between scientific objectivity and political advocacy without damaging conservation science's credibility. The value of this guidance, however, may be restricted by limited recognition of credibility's multidimensionality and emergent nature: it emerges through perceptions of expertise, goodwill, and trustworthiness. We used content analysis of the literature to determine how credibility is framed in conservation science as it relates to apparent contradictions between science and advocacy. Credibility typically was framed as a static entity lacking dimensionality. Authors identified expertise or trustworthiness as important, but rarely mentioned goodwill. They usually did not identify expertise, goodwill, or trustworthiness as dimensions of credibility or recognize interactions among these 3 dimensions of credibility. This oversimplification may limit the ability of conservation scientists to contribute to biodiversity conservation. Accounting for the emergent quality and multidimensionality of credibility should enable conservation scientists to advance biodiversity conservation more effectively. PMID:26041036

  20. Targeted gene flow for conservation.

    PubMed

    Kelly, Ella; Phillips, Ben L

    2016-04-01

    Anthropogenic threats often impose strong selection on affected populations, causing rapid evolutionary responses. Unfortunately, these adaptive responses are rarely harnessed for conservation. We suggest that conservation managers pay close attention to adaptive processes and geographic variation, with an eye to using them for conservation goals. Translocating pre-adapted individuals into recipient populations is currently considered a potentially important management tool in the face of climate change. Targeted gene flow, which involves moving individuals with favorable traits to areas where these traits would have a conservation benefit, could have a much broader application in conservation. Across a species' range there may be long-standing geographic variation in traits or variation may have rapidly developed in response to a threatening process. Targeted gene flow could be used to promote natural resistance to threats to increase species resilience. We suggest that targeted gene flow is a currently underappreciated strategy in conservation that has applications ranging from the management of invasive species and their impacts to controlling the impact and virulence of pathogens. © 2015 Society for Conservation Biology.

  1. Framing conservation on private lands: conserving oak in Oregon's Willamette Valley

    Treesearch

    A. Paige Fischer; John C. Bliss

    2009-01-01

    Conserving threatened habitats on private lands requires policies that advance the interests of landowners and natural resource professionals alike. Through qualitative analysis of individual and focus-group interviews, we compared how family forest owners and natural resource professionals frame conservation of threatened habitat: the oak woodlands and savanna in...

  2. 76 FR 22785 - Wetland Conservation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... Wetland Conservation AGENCY: Office of the Secretary, United States Department of Agriculture (USDA..., U.S. Department of Agriculture, Natural Resources Conservation Service, Room 6819, South Building, P... recordkeeping requirements subject to the Paperwork Reduction Act. Background Existing wetland conservation...

  3. Conservation systems in the Southeast

    USDA-ARS?s Scientific Manuscript database

    This presentation describes how conservation systems that include non-inversion tillage and cover crops, a key component of conservation systems, are managed in the Southeast to maximize benefits. Benefits include weed suppression, moisture conservation, and increased organic matter contents. Mana...

  4. Proton Transfer from C-6 of Uridine 5′-Monophosphate Catalyzed by Orotidine 5′-Monophosphate Decarboxylase: Formation and Stability of a Vinyl Carbanion Intermediate and the Effect of a 5-Fluoro Substituent

    PubMed Central

    Tsang, Wing-Yin; Wood, B. McKay; Wong, Freeman M.; Wu, Weiming; Gerlt, John A.; Amyes, Tina L.; Richard, John P.

    2012-01-01

    The exchange for deuterium of the C-6 protons of uridine 5′-monophosphate (UMP) and 5-fluorouridine 5′-monophosphate (F-UMP) catalyzed by yeast orotidine 5′-monophosphate decarboxylase (ScOMPDC) at pD 6.5 – 9.3 and 25 °C was monitored by 1H NMR spectroscopy. Deuterium exchange proceeds by proton transfer from C-6 of the bound nucleotide to the deprotonated side chain of Lys-93 to give the enzyme-bound vinyl carbanion. The pD-rate profiles for kcat give turnover numbers for deuterium exchange into enzyme-bound UMP and F-UMP of 1.2 × 10−5 and 0.041 s−1, respectively, so that the 5-fluoro substituent results in a 3400-fold increase in the first-order rate constant for deuterium exchange. The binding of UMP and F-UMP to ScOMPDC results in 0.5 and 1.4 unit decreases, respectively, in the pKa of the side chain of the catalytic base Lys-93, showing that these nucleotides bind preferentially to the deprotonated enzyme. We also report the first carbon acid pKas for proton transfer from C-6 of uridine (pKCH = 28.8) and 5-fluorouridine (pKCH = 25.1) in aqueous solution. The stabilizing effects of the 5-fluoro substituent on C-6 carbanion formation in solution (5 kcal/mol) and at ScOMPDC (6 kcal/mol) are similar. The binding of UMP and F-UMP to ScOMPDC results in a greater than 5 × 109-fold increase in the equilibrium constant for proton transfer from C-6 so that ScOMPDC stabilizes the bound vinyl carbanions, relative to the bound nucleotides, by at least 13 kcal/mol. The pD-rate profile for kcat/Km for deuterium exchange into F-UMP gives the intrinsic second-order rate constant for exchange catalyzed by the deprotonated enzyme as 2300 M−1 s−1. This was used to calculate a total rate acceleration for ScOMPDC-catalyzed deuterium exchange of 3 × 1010 M−1, which corresponds to a transition state stabilization for deuterium exchange of 14 kcal/mol. We conclude that a large portion of the total transition state stabilization for the decarboxylation of

  5. S-Adenosyl-S-carboxymethyl-l-homocysteine: a novel cofactor found in the putative tRNA-modifying enzyme CmoA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Byrne, Robert T.; Whelan, Fiona; Aller, Pierre

    2013-06-01

    The putative methyltransferase CmoA is involved in the nucleoside modification of transfer RNA. X-ray crystallography and mass spectrometry are used to show that it contains a novel SAM derivative, S-adenosyl-S-carboxymethyl-l-homocysteine, in which the donor methyl group is replaced by a carboxymethyl group. Uridine at position 34 of bacterial transfer RNAs is commonly modified to uridine-5-oxyacetic acid (cmo{sup 5}U) to increase the decoding capacity. The protein CmoA is involved in the formation of cmo{sup 5}U and was annotated as an S-adenosyl-l-methionine-dependent (SAM-dependent) methyltransferase on the basis of its sequence homology to other SAM-containing enzymes. However, both the crystal structure of Escherichiamore » coli CmoA at 1.73 Å resolution and mass spectrometry demonstrate that it contains a novel cofactor, S-adenosyl-S-carboxymethyl-l-homocysteine (SCM-SAH), in which the donor methyl group is substituted by a carboxymethyl group. The carboxyl moiety forms a salt-bridge interaction with Arg199 that is conserved in a large group of CmoA-related proteins but is not conserved in other SAM-containing enzymes. This raises the possibility that a number of enzymes that have previously been annotated as SAM-dependent are in fact SCM-SAH-dependent. Indeed, inspection of electron density for one such enzyme with known X-ray structure, PDB entry http://scripts.iucr.org/cgi-bin/cr.cgi?rm, suggests that the active site contains SCM-SAH and not SAM.« less

  6. A comparison of global conservation prioritization models with spatial spending patterns of conservation nongovernmental organizations.

    PubMed

    Holmes, George; Scholfield, Katherine; Brockington, Dan

    2012-08-01

    In recent decades, various conservation organizations have developed models to prioritize locations for conservation. Through a survey of the spending patterns of 281 conservation nongovernmental organizations (NGOs), we examined the relation between 2 such models and spatial patterns of spending by conservation NGOs in 44 countries in sub-Saharan Africa. We tested whether, at the country level, the proportion of a country designated as a conservation priority was correlated with where NGOs spent money. For one model (the combination of Conservation International's hotspots and High Biodiversity Wilderness Areas, which are areas of high endemism with high or low levels of vegetation loss respectively), there was no relation between the proportion of a country designated as a priority and levels of NGO spending, including by the NGO associated with the model. In the second model (Global 200), the proportion of a country designated as a priority and the amount of money spent by NGOs were significantly and positively related. Less money was spent in countries in northern and western sub-Saharan Africa than countries in southern and eastern Africa, relative to the proportion of the country designated as a conservation priority. We suggest that on the basis of our results some NGOs consider increasing their spending on the areas designated as of conservation priority which are currently relatively underfunded, although there are economic, political, cultural, historical, biological, and practical reasons why current spending patterns may not align with priority sites. ©2012 Society for Conservation Biology.

  7. What's Wrong With Conservation Education?

    ERIC Educational Resources Information Center

    Hobart, Willis L.

    1972-01-01

    Conservation and conservation education are critically examined, their definitions, foundations, principles, concepts, weaknesses, failures, and successes. It is concluded educators must first educate themselves, or environmental education will fail the same way conservation education has failed to educate Americans to the intricate…

  8. Creative Soil Conservation

    ERIC Educational Resources Information Center

    Smith, Martha

    2010-01-01

    Take plant lessons outdoors with this engaging and inquiry-based activity in which third-grade students learn how to apply soil conservation methods to growing plants. They also collect data and draw conclusions about the effectiveness of their method of soil conservation. An added benefit to this activity is that the third-grade students played…

  9. Conservation--Selected Bibliography.

    ERIC Educational Resources Information Center

    Australian Conservation Foundation, Parkville, Victoria.

    Developed by the Australian Conservation Foundation to meet the need for a general conservation bibliography, this booklet offers resources for a wide spectrum of possible users. Material selected is that which is relevant and helpful for conservationists in their various fields of activity and what is likely to be in print and obtainable without…

  10. Defining conservation targets on a landscape-scale

    USGS Publications Warehouse

    Benscoter, A.M.; Romañach, Stephanie; Brandt, Laura A.

    2015-01-01

    Conservation planning, the process of deciding how to protect, conserve, enhance and(or) minimize loss of natural and cultural resources, is a fundamental process to achieve conservation success in a time of rapid environmental change. Conservation targets, the measurable expressions of desired resource conditions, are an important tool in biological planning to achieve effective outcomes. Conservation targets provide a focus for planning, design, conservation action, and collaborative monitoring of environmental trends to guide landscape-scale conservation to improve the quality and quantity of key ecological and cultural resources. It is essential to have an iterative and inclusive method to define conservation targets that is replicable and allows for the evaluation of the effectiveness of conservation targets over time. In this document, we describe a process that can be implemented to achieve landscape-scale conservation, which includes defining conservation targets. We also describe what has been accomplished to date (September 2015) through this process for the Peninsular Florida Landscape Conservation Cooperative (PFLCC).

  11. Motivations for conserving urban biodiversity.

    PubMed

    Dearborn, Donald C; Kark, Salit

    2010-04-01

    In a time of increasing urbanization, the fundamental value of conserving urban biodiversity remains controversial. How much of a fixed budget should be spent on conservation in urban versus nonurban landscapes? The answer should depend on the goals that drive our conservation actions, yet proponents of urban conservation often fail to specify the motivation for protecting urban biodiversity. This is an important shortcoming on several fronts, including a missed opportunity to make a stronger appeal to those who believe conservation biology should focus exclusively on more natural, wilder landscapes. We argue that urban areas do offer an important venue for conservation biology, but that we must become better at choosing and articulating our goals. We explored seven possible motivations for urban biodiversity conservation: preserving local biodiversity, creating stepping stones to nonurban habitat, understanding and facilitating responses to environmental change, conducting environmental education, providing ecosystem services, fulfilling ethical responsibilities, and improving human well-being. To attain all these goals, challenges must be faced that are common to the urban environment, such as localized pollution, disruption of ecosystem structure, and limited availability of land. There are, however, also challenges specific only to particular goals, meaning that different goals will require different approaches and actions. This highlights the importance of specifying the motivations behind urban biodiversity conservation. If the goals are unknown, progress cannot be assessed.

  12. National and international conservation efforts and their relevance to plant conservation in the Southwest

    Treesearch

    Nancy R. Morin

    2001-01-01

    Plant conservation in the United States benefits directly and indirectly from national and international conservation initiatives. The United Nations Convention on Biological Diversity, which began in December 1993, serves as a guiding force for conservation in the United States even though the U.S. is not a party to the convention. An international meeting in 1998 of...

  13. Readings in Wildlife and Fish Conservation, High School Conservation Curriculum Project.

    ERIC Educational Resources Information Center

    Ensminger, Jack

    This publication is a tentative edition of readings on Wildlife and Fish Conservation in Louisiana, and as such it forms part of one of the four units of study designed for an experimental high school course, the "High School Conservation Curriculum Project." The other three units are concerned with Forest Conervation, Soil and Water…

  14. 7 CFR 1466.10 - Conservation practices.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... practice implementation. (c) A participant will be eligible for payments for water conservation and... 7 Agriculture 10 2014-01-01 2014-01-01 false Conservation practices. 1466.10 Section 1466.10... Contracts and Payments § 1466.10 Conservation practices. (a) NRCS will determine the conservation practices...

  15. 7 CFR 1466.10 - Conservation practices.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... practice implementation. (c) A participant will be eligible for payments for water conservation and... 7 Agriculture 10 2013-01-01 2013-01-01 false Conservation practices. 1466.10 Section 1466.10... Contracts and Payments § 1466.10 Conservation practices. (a) NRCS will determine the conservation practices...

  16. 7 CFR 1466.10 - Conservation practices.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... practice implementation. (c) A participant will be eligible for payments for water conservation and... 7 Agriculture 10 2012-01-01 2012-01-01 false Conservation practices. 1466.10 Section 1466.10... Contracts and Payments § 1466.10 Conservation practices. (a) NRCS will determine the conservation practices...

  17. Orchid conservation: further links.

    PubMed

    Fay, Michael F

    2016-07-01

    Due in great part to their often complex interactions with mycorrhizal fungi, pollinators and host trees, Orchidaceae present particular challenges for conservation. Furthermore, orchids, as potentially the largest family of angiosperms with >26000 species, species complexes and frequent hybrid formation, are complex to catalogue. Following a highlight in 2015, a further seven papers focusing on orchids, their interactions with beneficial organisms, pollinators and mycorrhiza, and other factors relating to their conservation, including threats from human utilization and changing land use, are presented here. The production of an online flora of all known plants and an assessment of the conservation status of all known plant species as far as possible, to guide conservation action are the first two targets of the Global Strategy for Plant Conservation Without knowing how many species there are and how they should be circumscribed, neither of these targets is achievable. Orchids are a fascinating subject for fundamental research with rapid species evolution, specific organ structure and development, but they also suffer from high levels of threat. Effective orchid conservation must take account of the beneficial interactions with fungi and pollinators and the potentially detrimental effects of over-collection and changes in land use. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Simulation of a flexible spinning vehicle

    NASA Technical Reports Server (NTRS)

    Baudry, W. A.

    1972-01-01

    Results are presented of experimental investigation of the controlled and uncontrolled dynamical behavior of a rotating or artificial gravity space station including flexible body effects. A dynamically scaled model was supported by a spherical air bearing which provided a nearly moment free environment. Reaction jet system were provided for spin-up and spin-down and for damping of wobble motion. Two single-gimbal gyros were arranged as a control moment gyro wobble damping system. Remotely controllable movable masses were provided to simulate mass shift disturbances such as arise from crew motions. An active mass balance wobble damping system which acted to minimize the wobble motions induced by crew motions was also installed. Flexible body effects were provided by a pair of inertia augmentation booms. Inertia augmentation booms are contemplated for use on rotating space stations to cause the spin axis moment of inertia to be the largest of the three moments of inertia as is necessary to assure gyroscopic stability. Test runs were made with each of the control systems with the booms locked (rigid body) and unlocked (flexible body).

  19. Expression levels of uridine 5'-diphospho-glucuronosyltransferase genes in breast tissue from healthy women are associated with mammographic density.

    PubMed

    Haakensen, Vilde D; Biong, Margarethe; Lingjærde, Ole Christian; Holmen, Marit Muri; Frantzen, Jan Ole; Chen, Ying; Navjord, Dina; Romundstad, Linda; Lüders, Torben; Bukholm, Ida K; Solvang, Hiroko K; Kristensen, Vessela N; Ursin, Giske; Børresen-Dale, Anne-Lise; Helland, Aslaug

    2010-01-01

    Mammographic density (MD), as assessed from film screen mammograms, is determined by the relative content of adipose, connective and epithelial tissue in the female breast. In epidemiological studies, a high percentage of MD confers a four to six fold risk elevation of developing breast cancer, even after adjustment for other known breast cancer risk factors. However, the biologic correlates of density are little known. Gene expression analysis using whole genome arrays was performed on breast biopsies from 143 women; 79 women with no malignancy (healthy women) and 64 newly diagnosed breast cancer patients, both included from mammographic centres. Percent MD was determined using a previously validated, computerized method on scanned mammograms. Significance analysis of microarrays (SAM) was performed to identify genes influencing MD and a linear regression model was used to assess the independent contribution from different variables to MD. SAM-analysis identified 24 genes differentially expressed between samples from breasts with high and low MD. These genes included three uridine 5'-diphospho-glucuronosyltransferase (UGT) genes and the oestrogen receptor gene (ESR1). These genes were down-regulated in samples with high MD compared to those with low MD. The UGT gene products, which are known to inactivate oestrogen metabolites, were also down-regulated in tumour samples compared to samples from healthy individuals. Several single nucleotide polymorphisms (SNPs) in the UGT genes associated with the expression of UGT and other genes in their vicinity were identified. Three UGT enzymes were lower expressed both in breast tissue biopsies from healthy women with high MD and in biopsies from newly diagnosed breast cancers. The association was strongest amongst young women and women using hormonal therapy. UGT2B10 predicts MD independently of age, hormone therapy and parity. Our results indicate that down-regulation of UGT genes in women exposed to female sex hormones is

  20. Expression levels of uridine 5'-diphospho-glucuronosyltransferase genes in breast tissue from healthy women are associated with mammographic density

    PubMed Central

    2010-01-01

    Introduction Mammographic density (MD), as assessed from film screen mammograms, is determined by the relative content of adipose, connective and epithelial tissue in the female breast. In epidemiological studies, a high percentage of MD confers a four to six fold risk elevation of developing breast cancer, even after adjustment for other known breast cancer risk factors. However, the biologic correlates of density are little known. Methods Gene expression analysis using whole genome arrays was performed on breast biopsies from 143 women; 79 women with no malignancy (healthy women) and 64 newly diagnosed breast cancer patients, both included from mammographic centres. Percent MD was determined using a previously validated, computerized method on scanned mammograms. Significance analysis of microarrays (SAM) was performed to identify genes influencing MD and a linear regression model was used to assess the independent contribution from different variables to MD. Results SAM-analysis identified 24 genes differentially expressed between samples from breasts with high and low MD. These genes included three uridine 5'-diphospho-glucuronosyltransferase (UGT) genes and the oestrogen receptor gene (ESR1). These genes were down-regulated in samples with high MD compared to those with low MD. The UGT gene products, which are known to inactivate oestrogen metabolites, were also down-regulated in tumour samples compared to samples from healthy individuals. Several single nucleotide polymorphisms (SNPs) in the UGT genes associated with the expression of UGT and other genes in their vicinity were identified. Conclusions Three UGT enzymes were lower expressed both in breast tissue biopsies from healthy women with high MD and in biopsies from newly diagnosed breast cancers. The association was strongest amongst young women and women using hormonal therapy. UGT2B10 predicts MD independently of age, hormone therapy and parity. Our results indicate that down-regulation of UGT genes

  1. 77 FR 74500 - Proposed Habitat Conservation Plan/Natural Community Conservation Plan for Western Butte County...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-14

    ... is being prepared under the Endangered Species Act of 1973, as amended, and the California Natural Community Conservation Planning Act. The BRCP addresses State and Federal endangered species compliance... conservation plan pursuant to the federal Endangered Species Act (Act), and a natural community conservation...

  2. 43 CFR 427.1 - Water conservation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Water conservation. 427.1 Section 427.1... INTERIOR WATER CONSERVATION RULES AND REGULATIONS § 427.1 Water conservation. (a) In general. The Secretary shall encourage the full consideration and incorporation of prudent and responsible water conservation...

  3. 43 CFR 427.1 - Water conservation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Water conservation. 427.1 Section 427.1... INTERIOR WATER CONSERVATION RULES AND REGULATIONS § 427.1 Water conservation. (a) In general. The Secretary shall encourage the full consideration and incorporation of prudent and responsible water conservation...

  4. 43 CFR 427.1 - Water conservation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Water conservation. 427.1 Section 427.1... INTERIOR WATER CONSERVATION RULES AND REGULATIONS § 427.1 Water conservation. (a) In general. The Secretary shall encourage the full consideration and incorporation of prudent and responsible water conservation...

  5. 43 CFR 427.1 - Water conservation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Water conservation. 427.1 Section 427.1... INTERIOR WATER CONSERVATION RULES AND REGULATIONS § 427.1 Water conservation. (a) In general. The Secretary shall encourage the full consideration and incorporation of prudent and responsible water conservation...

  6. 43 CFR 427.1 - Water conservation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Water conservation. 427.1 Section 427.1... INTERIOR WATER CONSERVATION RULES AND REGULATIONS § 427.1 Water conservation. (a) In general. The Secretary shall encourage the full consideration and incorporation of prudent and responsible water conservation...

  7. Reasons to Conserve Nature.

    PubMed

    Pearson, Richard G

    2016-05-01

    Is it sufficient to base arguments for conservation on the intrinsic value of nature, regardless of the services and economic benefits that biodiversity provides for humans? This question underlies much recent debate that has been at times acrimonious and has led to calls for a more inclusive approach to conservation. Yet melding different ideologies within a unified conceptual framework has proven difficult. Here I describe an approach that recognizes the importance of the level of biological organization and spatial extent in determining the strength of alternative arguments for why we should conserve nature. I argue that the framework helps reconcile contrasting viewpoints and brings clarity to when different conservation management approaches (for instance, regulation versus monetary valuation) are most appropriate. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

  8. Prebiotic synthesis and reactions of nucleosides and nucleotides

    NASA Astrophysics Data System (ADS)

    Ferris, J. P.; Yanagawa, H.; Hagan, W. J.

    Diiminosuccinonitrile (DISN) has been investigated as a potential prebiotic phosphorylating agent. It is formed readily by the oxidation of diaminomaleonitrile (DAMN), a tetramer of HCN, DISN effects the cyclization of 3'-adenosine monophosphate to adenosine 2',3'-cyclic phosphate in up to 40% yield. The DISN-mediated phosphorylation of uridine to uridine monophosphate does not proceed efficiently in aqueous solution. The reaction of DISN and BrCN with uridine-5'-phosphate and uridine results in the formation of 2,2'-anhydronucleotides and 2,2'-anhydronucleosides respectively, and other reaction products resulting from an initial reaction at the 2'- and 3'-hydroxyl groups. The clay mineral catalysis of the cyclization of adenosine-3'-phosphate was investigated using homoionic montmorillonites.

  9. The prebiotic chemistry of nucleotides

    NASA Technical Reports Server (NTRS)

    Ferris, J. P.; Yanagawa, H.; Hagan, W. J., Jr.

    1984-01-01

    Diminosuccinonitrile (DISN), formed by the oxidation of diaminomaleonitrile, has been investigated as a potential prebiotic phosphorylating agent. DISN affects the cyclization of 3'-adenosine monophosphate to adenosine 2',3'-cyclic phosphate in up to 39 percent yield. The mechanism of this reaction was investigated. The DISN-mediated phosphorylation of uridine to uridine monophosphate does not proceed efficiencly in aqueous solution. The reaction of DISN with uridine-5'-phosphate and uridine results in the formation of 2,2'-anhydronucleotides and 2,2'-anhydronucleosides respectively, and other reaction products resulting from an initial reaction at the 2'- and 3'-hydroxyl groups. The clay mineral catalysis of the cyclization of adenosine-3'-phosphate was investigated using homoionic montmorillonites.

  10. The Prebiotic Chemistry of Nucleotides

    NASA Astrophysics Data System (ADS)

    Ferris, J. P.; Yanagawa, H.; Hagan, W. J., Jr.

    1984-12-01

    Diiminosuccinonitrile (DISN), formed by the oxidation of diaminomaleonitrile (DAMN), has been investigated as a potential prebiotic phosphorylating agent. DISN effects the cyclization of 3'-adenosine monophosphate to adenosine 2', 3'-cyclic phosphate in up to 39% yield. The mechanism of this reaction was investigated. The DISN-mediated phosphorylation of uridine to uridine monophosphate does not proceed efficiently in aqueous solution. The reaction of DISN with uridine-5'-phosphate and uridine results in the formation of 2,2'-anhydronucleotides and 2,2'-anhydronucleosides respectively, and other reaction products resulting from an initial reaction at the 2'- and 3'-hydroxyl groups. The clay mineral catalysis of the cyclization of adenosine-3'-phosphate was investigated using homoionic montmorillonites.

  11. 75 FR 5544 - Energy Conservation Program: Energy Conservation Standards for Metal Halide Lamp Fixtures: Public...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ...-2009-BT-STD-0018] RIN 1904-AC00 Energy Conservation Program: Energy Conservation Standards for Metal... certain metal halide lamp fixtures. This document announces that the period for submitting comments on the... identify the Framework Document for energy conservation standards for metal halide lamp fixtures and...

  12. Leadership: a new frontier in conservation science.

    PubMed

    Manolis, Jim C; Chan, Kai M; Finkelstein, Myra E; Stephens, Scott; Nelson, Cara R; Grant, Jacqualine B; Dombeck, Michael P

    2009-08-01

    Leadership is a critical tool for expanding the influence of conservation science, but recent advances in leadership concepts and practice remain underutilized by conservation scientists. Furthermore, an explicit conceptual foundation and definition of leadership in conservation science are not available in the literature. Here we drew on our diverse leadership experiences, our reading of leadership literature, and discussions with selected conservation science leaders to define conservation-science leadership, summarize an exploratory set of leadership principles that are applicable to conservation science, and recommend actions to expand leadership capacity among conservation scientists and practitioners. We define 2 types of conservation-science leadership: shaping conservation science through path-breaking research, and advancing the integration of conservation science into policy, management, and society at large. We focused on the second, integrative type of leadership because we believe it presents the greatest opportunity for improving conservation effectiveness. We identified 8 leadership principles derived mainly from the "adaptive leadership" literature: recognize the social dimension of the problem; cycle frequently through action and reflection; get and maintain attention; combine strengths of multiple leaders; extend your reach through networks of relationships; strategically time your effort; nurture productive conflict; and cultivate diversity. Conservation scientists and practitioners should strive to develop themselves as leaders, and the Society for Conservation Biology, conservation organizations, and academia should support this effort through professional development, mentoring, teaching, and research.

  13. 75 FR 59469 - Energy Conservation Program: Energy Conservation Standards for Residential Refrigerators...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-27

    ...The Energy Policy and Conservation Act (EPCA) prescribes energy conservation standards for various consumer products and commercial and industrial equipment, including residential refrigerators, refrigerator-freezers, and freezers. EPCA also requires the U.S. Department of Energy (DOE) to determine whether more stringent, amended standards for these products are technologically feasible and economically justified, and would save a significant amount of energy. In this NOPR, DOE proposes amended energy conservation standards for residential refrigerators, refrigerator- freezers, and freezers. The NOPR also announces a public meeting to receive comment on these proposed standards and associated analyses and results.

  14. 2'-O-methyl-5-formylcytidine (f5Cm), a new modified nucleotide at the 'wobble' of two cytoplasmic tRNAs Leu (NAA) from bovine liver.

    PubMed Central

    Païs de Barros, J P; Keith, G; El Adlouni, C; Glasser, A L; Mack, G; Dirheimer, G; Desgrès, J

    1996-01-01

    The nucleotide analysis of a cytoplasmic tRNA(Leu) isolated from bovine liver revealed the presence of an unknown modified nucleotide N. The corresponding N nucleoside was isolated by different enzymatic and chromatographic protocols from a partially purified preparation of this tRNA(Leu). Its chemical characterization was determined from its chromatographic properties, UV-absorption spectroscopy and mass spectrometric measurements, as well as from those of the borohydride reduced N nucleoside and its etheno-trimethylsilyl derivative. The structure of N was established as 2'-O-methyl-5-formylcytidine (f5CM), and its reduced derivative as 2'-O-methyl-5-hydroxy-methylcytidine (om5Cm). By sequencing the bovine liver tRNA(Leu), the structure of the anticodon was determined as f5CmAA. In addition, the nucleotide sequence showed two primary structures differing only by the nucleotide 47c which is either uridine or adenosine. The two slightly differing bovine liver tRNAs-Leu(f5CmAA) are the only tRNAs so far sequenced which contain f5Cm. The role of such a modified cytidine at the first position of the anticodon is discussed in terms of decoding properties for the UUG and UUA leucine codons. Recently, precise evidence was obtained for the presence of f5Cm at the same position in tRNAs(Leu)(NAA) isolated from rabbit and lamb liver. Therefore, the 2'-O-methyl-5-formyl modification of cytidine at position 34 could be a general feature of cytoplasmic tRNAs(Leu)(NAA) in mammals. PMID:8628682

  15. 7 CFR 633.9 - Conservation plan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Conservation plan. 633.9 Section 633.9 Agriculture... AGRICULTURE LONG TERM CONTRACTING WATER BANK PROGRAM § 633.9 Conservation plan. (a) The program participant... conservation plan for the acreage designated under an agreement. (b) The conservation plan is the basis for the...

  16. Incentives for energy conservation

    NASA Astrophysics Data System (ADS)

    Ways to make homes and workplaces more energy efficient were discussed. Due to rise in the average price of world crude oil, the need for across the board energy savings was stressed. Tax credit for conservation measures and solar installations was considered to favor the affluent and to discriminate against the poor. New York's program to achieve energy conservation was described. Conservation is considered to be a cheaper way of meeting the energy needs than building new generating plants or producing synthetic gas from coal.

  17. Conservation Education: A Position Statement.

    ERIC Educational Resources Information Center

    Soil Conservation Society of America, Ankeny, IA.

    The Soil Conservation Society of America's (SCSA) aim is to advance the science and art of good land and water use. Conservation education has a significant role in achieving the wise use of these resources. In this report, perspectives are offered on: (1) the requirements for effective conservation education programs; (2) rationale for…

  18. Saving Money Through Energy Conservation.

    ERIC Educational Resources Information Center

    Presley, Michael H.; And Others

    This publication is an introduction to personal energy conservation. The first chapter presents a rationale for conserving energy and points out that private citizens control about one third of this country's energy consumption. Chapters two and three show how to save money by saving energy. Chapter two discusses energy conservation methods in the…

  19. Cognitive Conflict, Peers, and Volume Conservation.

    ERIC Educational Resources Information Center

    Renshaw, Peter D.

    This study investigates the effects of a training procedure on children's conservation. Volume conservation was induced in twenty-one 8-year-old non-conserving children by a procedure that combined two sources of conflict. First, the competing schemes used in making decisions on volumes were aroused; second, the non-conserver was made aware of a…

  20. Improving genetic conservation of tree species

    Treesearch

    Pam Allenstein; Jennifer DeWoody; David Gwaze; Valerie Hipkins; Gary Man; Anna Schoettle; Kirsty Shaw; Murphy Westwood

    2017-01-01

    The aim of this workshop breakout group session was to review significant gaps within each of three major themes (In-situ Conservation, Ex-situ Conservation, and Restoration of Species and Ecosystems) and to identify actionable solutions to move genetic conservation efforts forward. In order to identify solutions and action items for the tree conservation community,...

  1. Physiology in conservation translocations

    PubMed Central

    Tarszisz, Esther; Dickman, Christopher R.; Munn, Adam J.

    2014-01-01

    Conservation translocations aim to restore species to their indigenous ranges, protect populations from threats and/or reinstate ecosystem functions. They are particularly important for the conservation and management of rare and threatened species. Despite tremendous efforts and advancement in recent years, animal conservation translocations generally have variable success, and the reasons for this are often uncertain. We suggest that when little is known about the physiology and wellbeing of individuals either before or after release, it will be difficult to determine their likelihood of survival, and this could limit advancements in the science of translocations for conservation. In this regard, we argue that physiology offers novel approaches that could substantially improve translocations and associated practices. As a discipline, it is apparent that physiology may be undervalued, perhaps because of the invasive nature of some physiological measurement techniques (e.g. sampling body fluids, surgical implantation). We examined 232 publications that dealt with translocations of terrestrial vertebrates and aquatic mammals and, defining ‘success’ as high or low, determined how many of these studies explicitly incorporated physiological aspects into their protocols and monitoring. From this review, it is apparent that physiological evaluation before and after animal releases could progress and improve translocation/reintroduction successes. We propose a suite of physiological measures, in addition to animal health indices, for assisting conservation translocations over the short term and also for longer term post-release monitoring. Perhaps most importantly, we argue that the incorporation of physiological assessments of animals at all stages of translocation can have important welfare implications by helping to reduce the total number of animals used. Physiological indicators can also help to refine conservation translocation methods. These approaches fall

  2. Physiology in conservation translocations.

    PubMed

    Tarszisz, Esther; Dickman, Christopher R; Munn, Adam J

    2014-01-01

    Conservation translocations aim to restore species to their indigenous ranges, protect populations from threats and/or reinstate ecosystem functions. They are particularly important for the conservation and management of rare and threatened species. Despite tremendous efforts and advancement in recent years, animal conservation translocations generally have variable success, and the reasons for this are often uncertain. We suggest that when little is known about the physiology and wellbeing of individuals either before or after release, it will be difficult to determine their likelihood of survival, and this could limit advancements in the science of translocations for conservation. In this regard, we argue that physiology offers novel approaches that could substantially improve translocations and associated practices. As a discipline, it is apparent that physiology may be undervalued, perhaps because of the invasive nature of some physiological measurement techniques (e.g. sampling body fluids, surgical implantation). We examined 232 publications that dealt with translocations of terrestrial vertebrates and aquatic mammals and, defining 'success' as high or low, determined how many of these studies explicitly incorporated physiological aspects into their protocols and monitoring. From this review, it is apparent that physiological evaluation before and after animal releases could progress and improve translocation/reintroduction successes. We propose a suite of physiological measures, in addition to animal health indices, for assisting conservation translocations over the short term and also for longer term post-release monitoring. Perhaps most importantly, we argue that the incorporation of physiological assessments of animals at all stages of translocation can have important welfare implications by helping to reduce the total number of animals used. Physiological indicators can also help to refine conservation translocation methods. These approaches fall under a

  3. Approved Practices in Soil Conservation.

    ERIC Educational Resources Information Center

    Foster, Albert B.

    This book is written for individuals who wish to apply conservation practices, especially those of soil and water conservation, without technical assistance, to meet one's own conditions, and within his own capability to apply them. To meet these needs, the book includes a discussion and description of soil and water conservation methods for the…

  4. Logic of energy conservation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schipper, L.; Darmstadter, J.

    1978-01-01

    Energy conservation is seen as a complex mix of economic and moral considerations, which should be applied to specific strategies for changing waste handling, lifestyle, growth, etc., after meaningful payoffs have been researched and identified. The author recommends measuring energy conservation in terms of primary energy resources saved, and evaluating changes in consumption patterns on the basis of indirect as well as direct energy use. He feels consideration should be given to the intensity of energy use as well as to before-and-after comparisons. Human factors and wellbeing need to be included in shifts from energy-intensive to labor-intensive equipment. Curtailment ofmore » energy supplies as a conservation technique is seen as less effective than substitution, changes in habit and attitude, and changes in the types of goods and services demanded. While add-on investments have short-term value, new capital-equipment investments offer greater energy and economic savings in the long run. The author cautions against using strict rules to determine energy efficiency by relating energy to gross national product. Conservation is seen as an economic stimulus when compared to the costs of not conserving. 14 references. (DCK)« less

  5. Group discussions regarding consumer energy conservation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    The results of a series of group discussions conducted to investigate consumer attitudes and motivations as they relate to energy conservation are described. Specifically, the study was designed to cast light on the following questions: (1) the background climate of opinion that acts as a frame of reference for energy conservation communications; (2) classification of consumers in terms of adherence to or rejection of a conservation ethic; (3) the relation of energy waste and conservation to the standard of living aspirations of Americans; (4) the dominant kinds of motivations that are likely to influence receptivity to communications designed to promotemore » energy conservation; (5) compatibility of counter-culture values with the conservation ethic; (6) kinds of beliefs held regarding the future role of alternative energy sources; (7) the likely effectiveness of economic incentives to energy conservation; (8) differences between teenager and pre-teen attitudes from adult attitudes.« less

  6. Planning for land use and conservation: Assessing GIS-based conservation software for land use planning

    Treesearch

    Rob Baldwin; Ryan Scherzinger; Don Lipscomb; Miranda Mockrin; Susan Stein

    2014-01-01

    Recent advances in planning and ecological software make it possible to conduct highly technical analyses to prioritize conservation investments and inform local land use planning. We review these tools, termed conservation planning tools, and assess the knowledge of a key set of potential users: the land use planning community. We grouped several conservation software...

  7. Site-directed mutagenesis studies on the uridine monophosphate binding sites of feedback inhibition in carbamoyl phosphate synthetase and effects on cytidine production by Bacillus amyloliquefaciens.

    PubMed

    Fang, Haitian; Liu, Huiyan; Chen, Ning; Zhang, Chenglin; Xie, Xixian; Xu, Qingyang

    2013-06-01

    A major problem when pyrimidine de novo biosynthesis is used for cytidine production is the existence of many negative regulatory factors. Cytidine biosynthesis in Bacillus amyloliquefaciens proceeds via a pathway that is controlled by uridine monophosphate (UMP) through feedback inhibition of carbamoyl phosphate synthetase (CPS), the enzyme that converts CO2, NH3, and glutamine to carbamoyl phosphate. In this study, the gene carB encoding the large subunit of CPS from B. amyloliquefaciens CYT1 was site directed, and the UMP binding sites of feedback inhibition in Bam-CPS are described. The residues Thr-941, Thr-970, and Lys-986 in CPS from B. amyloliquefaciens were subjected to site-directed mutagenesis to alter UMP's feedback inhibition of CPS. To find feedback-resistant B. amyloliquefaciens, the influence of the T941F, T970A, K986I, T941F/K986I, and T941F/T970A/K986I mutations on CPS enzymatic properties was studied. The recombinant B. amyloliquefaciens with mutated T941F/K986I and T941F/T970A/K986I CPS showed a 3.7- and 5.7-fold increase, respectively, in cytidine production in comparison with the control expressing wild-type CPS, which was more suitable for further application of the cytidine synthesis. To a certain extent, the 5 mutations were found to release the enzyme from UMP inhibition and to improve B. amyloliquefaciens cytidine-producing strains.

  8. Case study of building of conservation coalitions to conserve ecological interactions.

    PubMed

    Chen, Gao; Luo, Shihong; Mei, Nianshu; Shen, Dingfang; Sun, Weibang

    2015-12-01

    We engaged experts in various fields of study (pollination ecology, chemical ecology, and ethnobotany), invited community participation, and provided environmental education in an effort to conserve an endangered birthwort (Aristolochia delavayi) and a vulnerable pipevine swallowtail (Byasa daemonius). Scientists studied the uptake and sequestration of the secondary metabolites aristolochic acids from A. delavayi leaves by different stages of pipevine swallowtail as a defense mechanism; low fruit set of the myophilous A. delavayi due to pollinator limitation; and the emission of chemical signals that attract parasitic wasps by the prepupae of B. daemonius. The results of these studies were part of an education program delivered by personnel of non-governmental organizations. The program was devised to deliver information to the public about the health risks of consuming A. delavayi individuals (aristolochic-acid-associated cancers) and to establish a bridge between the public and scientific research. Following delivery of the program, the behavior of residents changed considerably. Community residents were involved in management activities, including participation in a program to promote understanding of ecological interactions between A. delavayi and B. daemonius; designing an in situ conservation site; monitoring A. delavayi and B. daemonius individuals; and promoting the natural fruit set of A. delavayi by scattering animal excrement to attract fly pollinators. The integration of scientific information and community participation appears to have resulted in an increase in abundance of threatened A. delavayi and B. daemonius populations. We believe the involvement of local people in conservation is necessary for successful species conservation. © 2015 Society for Conservation Biology.

  9. The Work of the Civilian Conservation Corps: Pioneering Conservation in Louisiana

    Treesearch

    James P. Barnett; Anna C. Burns

    2016-01-01

    The Civilian Conservation Corps (CCC) was a public work relief program that operated from 1933 to 1942 in the United States for unemployed, unmarried men from relief families, ages 18-25. A part of the New Deal of U.S. President Franklin D. Roosevelt, it provided unskilled manual labor jobs related to the conservation and development of natural resources on the Nation’...

  10. 78 FR 55889 - Energy Conservation Program: Energy Conservation Standards for Commercial Refrigeration Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-11

    ...The Energy Policy and Conservation Act of 1975 (EPCA), as amended, prescribes energy conservation standards for various consumer products and certain commercial and industrial equipment, including commercial refrigeration equipment (CRE). EPCA also requires the U.S. Department of Energy (DOE) to determine whether more-stringent, amended standards would be technologically feasible and economically justified, and would save a significant amount of energy. In this notice, DOE proposes amended energy conservation standards for commercial refrigeration equipment. The notice also announces a public meeting to receive comment on these proposed standards and associated analyses and results.

  11. Water Conservation Resource List.

    ERIC Educational Resources Information Center

    NJEA Review, 1981

    1981-01-01

    Alarmed by the growing water shortage, the New Jersey State Office of Dissemination has prepared this annotated list of free or inexpensive instructional materials for teaching about water conservation, K-l2. A tipsheet for home water conservation is appended. (Editor/SJL)

  12. Conservation Physiology and Conservation Pathogens: White-Nose Syndrome and Integrative Biology for Host-Pathogen Systems.

    PubMed

    Willis, Craig K R

    2015-10-01

    Conservation physiology aims to apply an understanding of physiological mechanisms to management of imperiled species, populations, or ecosystems. One challenge for physiologists hoping to apply their expertise to conservation is connecting the mechanisms we study, often in the laboratory, with the vital rates of populations in the wild. There is growing appreciation that infectious pathogens can threaten populations and species, and represent an important issue for conservation. Conservation physiology has much to offer in terms of addressing the threat posed to some host species by infectious pathogens. At the same time, the well-developed theoretical framework of disease ecology could provide a model to help advance the application of physiology to a range of other conservation issues. Here, I use white-nose syndrome (WNS) in hibernating North American bats as an example of a conservation problem for which integrative physiological research has been a critical part of research and management. The response to WNS highlights the importance of a well-developed theoretical framework for the application of conservation physiology to a particular threat. I review what is known about physiological mechanisms associated with mortality from WNS and emphasize the value of combining a strong theoretical background with integrative physiological studies in order to connect physiological mechanisms with population processes and thereby maximize the potential benefits of conservation physiology. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  13. Local understandings of conservation in southeastern Mexico and their implications for community-based conservation as an alternative paradigm.

    PubMed

    Reyes-Garcia, Victoria; Ruiz-Mallen, Isabel; Porter-Bolland, Luciana; Garcia-Frapolli, Eduardo; Ellis, Edward A; Mendez, Maria-Elena; Pritchard, Diana J; Sanchez-Gonzalez, María-Consuelo

    2013-08-01

    Since the 1990s national and international programs have aimed to legitimize local conservation initiatives that might provide an alternative to the formal systems of state-managed or otherwise externally driven protected areas. We used discourse analysis (130 semistructured interviews with key informants) and descriptive statistics (679 surveys) to compare local perceptions of and experiences with state-driven versus community-driven conservation initiatives. We conducted our research in 6 communities in southeastern Mexico. Formalization of local conservation initiatives did not seem to be based on local knowledge and practices. Although interviewees thought community-based initiatives generated less conflict than state-managed conservation initiatives, the community-based initiatives conformed to the biodiversity conservation paradigm that emphasizes restricted use of and access to resources. This restrictive approach to community-based conservation in Mexico, promoted through state and international conservation organizations, increased the area of protected land and had local support but was not built on locally relevant and multifunctional landscapes, a model that community-based conservation is assumed to advance. © 2013 Society for Conservation Biology.

  14. Preferred conservation policies of shark researchers.

    PubMed

    Shiffman, David S; Hammerschlag, Neil

    2016-08-01

    There is increasing concern about the conservation status of sharks. However, the presence of numerous different (and potentially mutually exclusive) policies complicates management implementation and public understanding of the process. We distributed an online survey to members of the largest professional shark and ray research societies to assess member knowledge of and attitudes toward different conservation policies. Questions covered society member opinions on conservation and management policies, personal histories of involvement in advocacy and management, and perceptions of the approach of conservation nongovernmental organizations (NGOs) to shark conservation. One hundred and two surveys were completed (overall response rate 21%). Respondents considered themselves knowledgeable about and actively involved in conservation and management policy; a majority believed scientists have a responsibility to advocate for conservation (75%), and majorities have sent formal public comments to policymakers (54%) and included policy suggestions in their papers (53%). They believe sustainable shark fisheries are possible, are currently happening today (in a few places), and should be the goal instead of banning fisheries. Respondents were generally less supportive of newer limit-based (i.e., policies that ban exploitation entirely without a species-specific focus) conservation policy tools, such as shark sanctuaries and bans on the sale of shark fins, than of target-based fisheries management tools (i.e., policies that allow for sustainable harvest of species whose populations can withstand it), such as fishing quotas. Respondents were generally supportive of environmental NGO efforts to conserve sharks but raised concerns about some NGOs that they perceived as using incorrect information and focusing on the wrong problems. Our results show there is an ongoing debate in shark conservation and management circles relative to environmental policy on target-based natural

  15. Conservation Planning for Ecosystem Services

    PubMed Central

    Chan, Kai M. A; Shaw, M. Rebecca; Cameron, David R; Underwood, Emma C; Daily, Gretchen C

    2006-01-01

    Despite increasing attention to the human dimension of conservation projects, a rigorous, systematic methodology for planning for ecosystem services has not been developed. This is in part because flows of ecosystem services remain poorly characterized at local-to-regional scales, and their protection has not generally been made a priority. We used a spatially explicit conservation planning framework to explore the trade-offs and opportunities for aligning conservation goals for biodiversity with six ecosystem services (carbon storage, flood control, forage production, outdoor recreation, crop pollination, and water provision) in the Central Coast ecoregion of California, United States. We found weak positive and some weak negative associations between the priority areas for biodiversity conservation and the flows of the six ecosystem services across the ecoregion. Excluding the two agriculture-focused services—crop pollination and forage production—eliminates all negative correlations. We compared the degree to which four contrasting conservation network designs protect biodiversity and the flow of the six services. We found that biodiversity conservation protects substantial collateral flows of services. Targeting ecosystem services directly can meet the multiple ecosystem services and biodiversity goals more efficiently but cannot substitute for targeted biodiversity protection (biodiversity losses of 44% relative to targeting biodiversity alone). Strategically targeting only biodiversity plus the four positively associated services offers much promise (relative biodiversity losses of 7%). Here we present an initial analytical framework for integrating biodiversity and ecosystem services in conservation planning and illustrate its application. We found that although there are important potential trade-offs between conservation for biodiversity and for ecosystem services, a systematic planning framework offers scope for identifying valuable synergies. PMID

  16. 76 FR 47518 - Energy Conservation Program: Treatment of “Smart” Appliances in Energy Conservation Standards and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-05

    ... Conservation Program: Treatment of ``Smart'' Appliances in Energy Conservation Standards and Test Procedures... well as in test procedures used to demonstrate compliance with DOE's standards and qualification as an... development of energy conservation standards and test procedures for DOE's Appliance Standards Program and the...

  17. Cranes, Crops and Conservation: Understanding Human Perceptions of Biodiversity Conservation in South Korea's Civilian Control Zone

    NASA Astrophysics Data System (ADS)

    Kim, Jin-Oh; Steiner, Frederick; Mueller, Elizabeth

    2011-01-01

    South Korea's Civilian Control Zone (CCZ), a relatively untouched area due to tight military oversight since the end of Korean War, has received considerable attention nationally and internationally for its rich biodiversity. However, the exclusion of local communities from the process of defining problems and goals and of setting priorities for biodiversity conservation has halted a series of biodiversity conservation efforts. Through qualitative research, we explored CCZ farmers' views of key problems and issues and also the sources of their opposition to the government-initiated conservation approaches. Key findings include the farmers' concerns about the impact of conservation restrictions on their access to necessary resources needed to farm, wildlife impacts on the value of rice and other agricultural goods they produce, and farmers' strong distrust of government, the military, and planners, based on their experiences with past conservation processes. The findings regarding farmers' perceptions should prove useful for the design of future participatory planning processes for biodiversity conservation in the CCZ. This case highlights how conservative measures, perceived to be imposed from above—however scientifically valuable—can be undermined and suggests the value that must be placed on communication among planners and stakeholders.

  18. Cranes, crops and conservation: understanding human perceptions of biodiversity conservation in South Korea's Civilian Control Zone.

    PubMed

    Kim, Jin-Oh; Steiner, Frederick; Mueller, Elizabeth

    2011-01-01

    South Korea's Civilian Control Zone (CCZ), a relatively untouched area due to tight military oversight since the end of Korean War, has received considerable attention nationally and internationally for its rich biodiversity. However, the exclusion of local communities from the process of defining problems and goals and of setting priorities for biodiversity conservation has halted a series of biodiversity conservation efforts. Through qualitative research, we explored CCZ farmers' views of key problems and issues and also the sources of their opposition to the government-initiated conservation approaches. Key findings include the farmers' concerns about the impact of conservation restrictions on their access to necessary resources needed to farm, wildlife impacts on the value of rice and other agricultural goods they produce, and farmers' strong distrust of government, the military, and planners, based on their experiences with past conservation processes. The findings regarding farmers' perceptions should prove useful for the design of future participatory planning processes for biodiversity conservation in the CCZ. This case highlights how conservative measures, perceived to be imposed from above--however scientifically valuable--can be undermined and suggests the value that must be placed on communication among planners and stakeholders.

  19. 77 FR 10997 - Energy Conservation Program: Energy Conservation Standards for Distribution Transformers; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-24

    ... Conservation Program: Energy Conservation Standards for Distribution Transformers; Correction AGENCY: Office of... standards for distribution transformers. It was recently discovered that values in certain tables of the...,'' including distribution transformers. The Energy Policy Act of 1992 (EPACT 1992), Public Law 102-486, amended...

  20. A Note on Weak Solutions of Conservation Laws and Energy/Entropy Conservation

    NASA Astrophysics Data System (ADS)

    Gwiazda, Piotr; Michálek, Martin; Świerczewska-Gwiazda, Agnieszka

    2018-03-01

    A common feature of systems of conservation laws of continuum physics is that they are endowed with natural companion laws which are in such cases most often related to the second law of thermodynamics. This observation easily generalizes to any symmetrizable system of conservation laws; they are endowed with nontrivial companion conservation laws, which are immediately satisfied by classical solutions. Not surprisingly, weak solutions may fail to satisfy companion laws, which are then often relaxed from equality to inequality and overtake the role of physical admissibility conditions for weak solutions. We want to answer the question: what is a critical regularity of weak solutions to a general system of conservation laws to satisfy an associated companion law as an equality? An archetypal example of such a result was derived for the incompressible Euler system in the context of Onsager's conjecture in the early nineties. This general result can serve as a simple criterion to numerous systems of mathematical physics to prescribe the regularity of solutions needed for an appropriate companion law to be satisfied.

  1. 77 FR 4698 - Energy Conservation Program: Test Procedure and Energy Conservation Standard for Set-Top Boxes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-31

    ... Conservation Program: Test Procedure and Energy Conservation Standard for Set-Top Boxes and Network Equipment... comments on the request for information pertaining to the development of test procedures and energy conservation standards for set-top boxes and network equipment. The comment period is extended to March 15...

  2. Biodiversity Conservation and Conservation Biotechnology Tools

    USDA-ARS?s Scientific Manuscript database

    This special issue is dedicated to the in vitro tools and methods used to conserve the genetic diversity of rare and threatened species from around the world. Species that are on the brink of extinction, due to the rapid loss of genetic diversity and habitat, come mainly from resource poor areas the...

  3. Conservation through the economics lens.

    PubMed

    Farley, Joshua

    2010-01-01

    Although conservation is an inherently transdisciplinary issue, there is much to be gained from examining the problem through an economics lens. Three benefits of such an approach are laid out in this paper. First, many of the drivers of environmental degradation are economic in origin, and the better we understand them, the better we can conserve ecosystems by reducing degradation. Second, economics offers us a when-to-stop rule, which is equivalent to a when-to-conserve rule. All economic production is based on the transformation of raw materials provided by nature. As the economic system grows in physical size, it necessarily displaces and degrades ecosystems. The marginal benefits of economic growth are diminishing, and the marginal costs of ecological degradation are increasing. Conceptually, we should stop economic growth and focus on conservation when the two are equal. Third, economics can help us understand how to efficiently and justly allocate resources toward conservation, and this paper lays out some basic principles for doing so. Unfortunately, the field of economics is dominated by neoclassical economics, which builds an analytical framework based on questionable assumptions and takes an excessively disciplinary and formalistic approach. Conservation is a complex problem, and analysis from individual disciplinary lenses can make important contributions to conservation only when the resulting insights are synthesized into a coherent vision of the whole. Fortunately, there are a number of emerging transdisciplines, such as ecological economics and environmental management, that are dedicated to this task.

  4. Conservation of wading birds

    USGS Publications Warehouse

    Kushlan, J.A.

    1996-01-01

    The conservation and management of wading birds has received considerable attention over the past twenty years, through research, population monitoring, habitat protection, and through activities of specialist groups devoted to all three groups, the herons, ibises and allies, and flamingos. While populations are best known in North America, greatest advances in knowledge may have come in Australasia. The status of most species and many populations is now sufficiently known to allow assessment of risk. Conservation and management techniques allow creation of global and regional action plans for conservation of many species. Global action plans are being developed, but few regional plans have been undertaken. Management of nesting sites is now particularly well appreciated. Although known in broad stroke, much remains to be learned about managing feeding habitat. Problems related to disturbance, conflict with humans, habitat loss, contaminants and other environmental stresses remain for some species and many populations. New challenges lie in creating conservation action that account for genetic stocks.

  5. Agricultural intensification escalates future conservation costs.

    PubMed

    Phelps, Jacob; Carrasco, Luis Roman; Webb, Edward L; Koh, Lian Pin; Pascual, Unai

    2013-05-07

    The supposition that agricultural intensification results in land sparing for conservation has become central to policy formulations across the tropics. However, underlying assumptions remain uncertain and have been little explored in the context of conservation incentive schemes such as policies for Reducing Emissions from Deforestation and forest Degradation, conservation, sustainable management, and enhancement of carbon stocks (REDD+). Incipient REDD+ forest carbon policies in a number of countries propose agricultural intensification measures to replace extensive "slash-and-burn" farming systems. These may result in conservation in some contexts, but will also increase future agricultural land rents as productivity increases, creating new incentives for agricultural expansion and deforestation. While robust governance can help to ensure land sparing, we propose that conservation incentives will also have to increase over time, tracking future agricultural land rents, which might lead to runaway conservation costs. We present a conceptual framework that depicts these relationships, supported by an illustrative model of the intensification of key crops in the Democratic Republic of Congo, a leading REDD+ country. A von Thünen land rent model is combined with geographic information systems mapping to demonstrate how agricultural intensification could influence future conservation costs. Once postintensification agricultural land rents are considered, the cost of reducing forest sector emissions could significantly exceed current and projected carbon credit prices. Our analysis highlights the importance of considering escalating conservation costs from agricultural intensification when designing conservation initiatives.

  6. Agricultural intensification escalates future conservation costs

    PubMed Central

    Phelps, Jacob; Carrasco, Luis Roman; Webb, Edward L.; Koh, Lian Pin; Pascual, Unai

    2013-01-01

    The supposition that agricultural intensification results in land sparing for conservation has become central to policy formulations across the tropics. However, underlying assumptions remain uncertain and have been little explored in the context of conservation incentive schemes such as policies for Reducing Emissions from Deforestation and forest Degradation, conservation, sustainable management, and enhancement of carbon stocks (REDD+). Incipient REDD+ forest carbon policies in a number of countries propose agricultural intensification measures to replace extensive “slash-and-burn” farming systems. These may result in conservation in some contexts, but will also increase future agricultural land rents as productivity increases, creating new incentives for agricultural expansion and deforestation. While robust governance can help to ensure land sparing, we propose that conservation incentives will also have to increase over time, tracking future agricultural land rents, which might lead to runaway conservation costs. We present a conceptual framework that depicts these relationships, supported by an illustrative model of the intensification of key crops in the Democratic Republic of Congo, a leading REDD+ country. A von Thünen land rent model is combined with geographic information systems mapping to demonstrate how agricultural intensification could influence future conservation costs. Once postintensification agricultural land rents are considered, the cost of reducing forest sector emissions could significantly exceed current and projected carbon credit prices. Our analysis highlights the importance of considering escalating conservation costs from agricultural intensification when designing conservation initiatives. PMID:23589860

  7. Some guiding concepts for conservation biology.

    PubMed

    Lindenmayer, David; Hunter, Malcolm

    2010-12-01

    The search for generalities in ecology has often been thwarted by contingency and ecological complexity that limit the development of predictive rules. We present a set of concepts that we believe succinctly expresses some of the fundamental ideas in conservation biology. (1) Successful conservation management requires explicit goals and objectives. (2) The overall goal of biodiversity management will usually be to maintain or restore biodiversity, not to maximize species richness. (3) A holistic approach is needed to solve conservation problems. (4) Diverse approaches to management can provide diverse environmental conditions and mitigate risk. (5) Using nature's template is important for guiding conservation management, but it is not a panacea. (6) Focusing on causes not symptoms enhances efficacy and efficiency of conservation actions. (7) Every species and ecosystem is unique, to some degree. (8) Threshold responses are important but not ubiquitous. (9) Multiple stressors often exert critical effects on species and ecosystems. (10) Human values are variable and dynamic and significantly shape conservation efforts. We believe most conservation biologists will broadly agree these concepts are important. That said, an important part of the maturation of conservation biology as a discipline is constructive debate about additional or alternative concepts to those we have proposed here. Therefore, we have established a web-based, online process for further discussion of the concepts outlined in this paper and developing additional ones. © 2010 Society for Conservation Biology.

  8. On nonepistemic values in conservation biology.

    PubMed

    Baumgaertner, Bert; Holthuijzen, Wieteke

    2017-02-01

    Conservation biology is a uniquely interdisciplinary science with strong roots in ecology, but it also embraces a value-laden and mission-oriented framework. This combination of science and values causes conservation biology to be at the center of critique regarding the discipline's scientific credibility-especially the division between the realms of theory and practice. We identify this dichotomy between seemingly objective (fact-based) and subjective (value-laden) practices as the measure-value dichotomy, whereby measure refers to methods and analyses used in conservation biology (i.e., measuring biodiversity) and value refers to nonepistemic values. We reviewed and evaluated several landmark articles central to the foundation of conservation biology and concepts of biodiversity with respect to their attempts to separate measures and values. We argue that the measure-value dichotomy is false and that conservation biology can make progress in ways unavailable to other disciplines because its practitioners are tasked with engaging in both the realm of theory and the realm of practice. The entanglement of measures and values is by no means a weakness of conservation biology. Because central concepts such as biodiversity contain both factual and evaluative aspects, conservation biologists can make theoretical progress by examining, reviewing, and forming the values that are an integral part of those concepts. We suggest that values should be included and analyzed with respect to the methods, results, and conclusions of scientific work in conservation biology. © 2016 Society for Conservation Biology.

  9. Delayed hysteroscopic resection of retained tissues and uterine conservation after conservative treatment for placenta accreta.

    PubMed

    Hequet, Delphine; Morel, Olivier; Soyer, Philippe; Gayat, Etienne; Malartic, Cécile; Barranger, Emmanuel

    2013-12-01

    Conservative management of both the uterus and the abnormal placenta, which is left inside the uterus at the time of delivery, is one option of placenta accreta management. Complete elimination of the residual placenta is the main challenge of this procedure. To report the role, efficacy and safety of hysteroscopic resection in women presenting with severe pelvic pain and chronic intra-uterine retention after conservative treatment of placenta accreta. Four consecutive women who were treated with hysteroscopic resection of retained tissues after conservative treatment of placenta accreta or percreta at the time of delivery. Clinical files and surgical procedures were reviewed. All procedures were performed because of chronic pelvic pain and the absence of a complete spontaneous placental elimination. All procedures were successful and uneventful. The uterus was conserved with a complete disappearance of the symptoms in the four women, and two of them became pregnant. Hysteroscopic resection seems effective and safe for shortening the duration of placental elimination after conservative treatment in women with severe pelvic pain due to uterine retention. This approach allows conserving the uterus and future fertility. © 2013 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  10. Conservation Science Fair Projects.

    ERIC Educational Resources Information Center

    Soil Conservation Society of America, Ankeny, IA.

    Included are ideas, suggestions, and examples for selecting and designing conservation science projects. Over 70 possible conservation subject areas are presented with suggested projects. References are cited with each of these subject areas, and a separate list of annotated references is included. The references pertain to general subject…

  11. Adapting the bioblitz to meet conservation needs.

    PubMed

    Parker, Sophie S; Pauly, Gregory B; Moore, James; Fraga, Naomi S; Knapp, John J; Principe, Zachary; Brown, Brian V; Randall, John M; Cohen, Brian S; Wake, Thomas A

    2018-03-01

    When conservation strategies require new, field-based information, practitioners must find the best ways to rapidly deliver high-quality survey data. To address this challenge, several rapid-assessment approaches have been developed since the early 1990s. These typically involve large areas, take many months to complete, and are not appropriate when conservation-relevant survey data are urgently needed for a specific locale. In contrast, bioblitzes are designed for quick collection of site-specific survey data. Although bioblitzes are commonly used to achieve educational or public-engagement goals, conservation practitioners are increasingly using a modified bioblitz approach to generate conservation-relevant data while simultaneously enhancing research capacity and building working partnerships focused on conservation concerns. We term these modified events expert bioblitzes. Several expert bioblitzes have taken place on lands of conservation concern in Southern California and have involved collaborative efforts of government agencies, nonprofit organizations, botanic gardens, museums, and universities. The results of expert bioblitzes directly informed on-the-ground conservation and decision-making; increased capacity for rapid deployment of expert bioblitzes in the future; and fostered collaboration and communication among taxonomically and institutionally diverse experts. As research and conservation funding becomes increasingly scarce, expert bioblitzes can play an increasingly important role in biodiversity conservation. © 2018 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  12. 76 FR 43941 - Energy Conservation Program: Energy Conservation Standards for Direct Heating Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-22

    ... DEPARTMENT OF ENERGY 10 CFR Part 430 [Docket Number EERE-2011-BT-STD-0047] RIN 1904-AC56 Energy Conservation Program: Energy Conservation Standards for Direct Heating Equipment AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION: Notice of proposed rulemaking and announcement...

  13. 77 FR 59719 - Energy Conservation Program: Energy Conservation Standards for Residential Clothes Washers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... DEPARTMENT OF ENERGY 10 CFR Parts 429 and 430 [Docket Number EERE-2008-BT-STD-0019] RIN 1904-AB90 Energy Conservation Program: Energy Conservation Standards for Residential Clothes Washers AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION: Notice of effective date and...

  14. Youth Conservation Corps Guidance.

    ERIC Educational Resources Information Center

    Fish and Wildlife Service (Dept. of Interior), Washington, DC.

    This document provides guidelines for operating Youth Conservation Corps programs under both the Fish and Wildlife Service and the National Park Service. The guide contains 11 units that cover the following topics: (1) enrollees; (2) enrollee payroll; (3) enrollee problems; (4) Youth Conservation Corps staff; (5) accounting; (6) operations; (7)…

  15. Achieving open access to conservation science.

    PubMed

    Fuller, Richard A; Lee, Jasmine R; Watson, James E M

    2014-12-01

    Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay-per-view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per-article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation-oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. © 2014 The Authors. Conservation Biology published by Wiley Periodicals, Inc., on behalf of the Society for

  16. Creating biodiversity partnerships: The Nature Conservancy's perspective

    NASA Astrophysics Data System (ADS)

    Sawhill, John C.

    1996-11-01

    The Nature Conservancy is an international organization dedicated to the mission of conserving biodiversity throughout the world. By working in a nonconfrontational manner, an approach that has promoted both government and corporate sponsorship of its activities, The Nature Conservancy has developed symbiotic relationships with many electric utility companies. Drawing on the organization's experiences, and the experiences of the author as the President and Chief Executive Officer of The Nature Conservancy, five broad areas of cooperation between conservation organizations and the utility industry are explored: landmanagement agreements, mitigation projects, conflictavoidance programs, program support, and volunteer activities. The paper is concluded with comments on the future trends of biodiversity conservation, challenging the electric utility industry to become involved with conservation efforts by forming cooperative partnerships.

  17. 7 CFR 766.110 - Conservation Contract.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... floodplains; (iii) Areas of high water quality or scenic value; (iv) Historic or cultural properties listed in..., or 50 years. (e) Conservation management plan. The Agency, through the recommendations of the Conservation Contract review team, is responsible for approving the conservation management plan. (f...

  18. 7 CFR 766.110 - Conservation Contract.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... floodplains; (iii) Areas of high water quality or scenic value; (iv) Historic or cultural properties listed in..., or 50 years. (e) Conservation management plan. The Agency, through the recommendations of the Conservation Contract review team, is responsible for approving the conservation management plan. (f...

  19. 24 CFR 242.82 - Energy conservation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Energy conservation. 242.82 Section... INSURANCE FOR HOSPITALS Miscellaneous Requirements § 242.82 Energy conservation. Construction, mechanical equipment, and energy and metering selections shall provide cost-effective energy conservation in accordance...

  20. 24 CFR 242.82 - Energy conservation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Energy conservation. 242.82 Section... INSURANCE FOR HOSPITALS Miscellaneous Requirements § 242.82 Energy conservation. Construction, mechanical equipment, and energy and metering selections shall provide cost-effective energy conservation in accordance...

  1. 24 CFR 242.82 - Energy conservation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Energy conservation. 242.82 Section... INSURANCE FOR HOSPITALS Miscellaneous Requirements § 242.82 Energy conservation. Construction, mechanical equipment, and energy and metering selections shall provide cost-effective energy conservation in accordance...

  2. 24 CFR 242.82 - Energy conservation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Energy conservation. 242.82 Section... INSURANCE FOR HOSPITALS Miscellaneous Requirements § 242.82 Energy conservation. Construction, mechanical equipment, and energy and metering selections shall provide cost-effective energy conservation in accordance...

  3. 24 CFR 242.82 - Energy conservation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Energy conservation. 242.82 Section... INSURANCE FOR HOSPITALS Miscellaneous Requirements § 242.82 Energy conservation. Construction, mechanical equipment, and energy and metering selections shall provide cost-effective energy conservation in accordance...

  4. Modeling soil conservation, water conservation and their tradeoffs: a case study in Beijing.

    PubMed

    Bai, Yang; Ouyang, Zhiyun; Zheng, Hua; Li, Xiaoma; Zhuang, Changwei; Jiang, Bo

    2012-01-01

    Natural ecosystems provide society with important goods and services. With the rapid increase in human populations and excessive utilization of natural resources, humans frequently enhance the production of some services at the expense of the others. Although the need for tradeoffs between conservation and development is urgent, the lack of efficient methods to assess such tradeoffs has impeded progress. Three land use strategy scenarios (development scenario, plan trend scenario and conservation scenario) were created to forecast potential changes in ecosystem services from 2007 to 2050 in Beijing, China. GIS-based techniques were used to map spatial and temporal distribution and changes in ecosystem services for each scenario. The provision of ecosystem services differed spatially, with significant changes being associated with different scenarios. Scenario analysis of water yield (as average annual yield) and soil retention (as retention rate per unit area) for the period 2007 to 2050 indicated that the highest values for these parameters were predicted for the forest habitat under all three scenarios. Annual yield/retention of forest, shrub, and grassland ranked the highest in the conservation scenario. Total water yield and soil retention increased in the conservation scenario and declined dramatically in the other two scenarios, especially the development scenario. The conservation scenario was the optimal land use strategy, resulting in the highest soil retention and water yield. Our study suggests that the evaluation and visualization of ecosystem services can effectively assist in understanding the tradeoffs between conservation and development. Results of this study have implications for planning and monitoring future management of natural capital and ecosystem services, which can be integrated into land use decision-making.

  5. Significance of Perceived Social Expectation and Implications to Conservation Education: Turtle Conservation as a Case Study

    NASA Astrophysics Data System (ADS)

    Lo, Alex Y.; Chow, Alex T.; Cheung, Sze Man

    2012-11-01

    The likelihood of participating in wildlife conservation programs is dependent on social influences and circumstances. This view is validated by a case study of behavioral intention to support conservation of Asian turtles. A total of 776 college students in China completed a questionnaire survey designed to identify factors associated with their intention to support conservation. A regression model explained 48 % of variance in the level of intention. Perceived social expectation was the strongest predictor, followed by attitudes toward turtle protection and perceived behavioral control, altogether explaining 44 %. Strong ethics and socio-economic variables had some statistical significant impacts and accounted for 3 % of the variance. The effects of general environmental awareness, trust and responsibility ascription were modest. Knowledge about turtles was a weak predictor. We conclude that perceived social expectation is a limiting factor of conservation behavior. Sustained interest and commitment to conservation can be created by enhancing positive social influences. Conservation educators should explore the potential of professionally supported, group-based actions that can nurture a sense of collective achievement as part of an educational campaign.

  6. Introducing Conservation of Momentum

    ERIC Educational Resources Information Center

    Brunt, Marjorie; Brunt, Geoff

    2013-01-01

    The teaching of the principle of conservation of linear momentum is considered (ages 15 + ). From the principle, the momenta of two masses in an isolated system are considered. Sketch graphs of the momenta make Newton's laws appear obvious. Examples using different collision conditions are considered. Conservation of momentum is considered…

  7. Strategies for Energy Conservation

    ERIC Educational Resources Information Center

    Rudd, Nancy M.; Longstreth, Molly

    1978-01-01

    Focusing on conservation in the residential area, the author describes five ways in which conservation can be encouraged or enforced: (1) higher prices, changed pricing structures, and/or taxes on energy to discourage use; (2) consumer education; (3) tax incentives and subsidies to promote installation of energy-saving equipment; (4) rationing;…

  8. 14 CFR 152.609 - Energy conservation practices.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Energy conservation practices. 152.609... (CONTINUED) AIRPORTS AIRPORT AID PROGRAM Energy Conservation in Airport Aid Program § 152.609 Energy conservation practices. Each sponsor shall require fuel and energy conservation practices in the operation and...

  9. 14 CFR 152.609 - Energy conservation practices.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Energy conservation practices. 152.609... (CONTINUED) AIRPORTS AIRPORT AID PROGRAM Energy Conservation in Airport Aid Program § 152.609 Energy conservation practices. Each sponsor shall require fuel and energy conservation practices in the operation and...

  10. 14 CFR 152.609 - Energy conservation practices.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Energy conservation practices. 152.609... (CONTINUED) AIRPORTS AIRPORT AID PROGRAM Energy Conservation in Airport Aid Program § 152.609 Energy conservation practices. Each sponsor shall require fuel and energy conservation practices in the operation and...

  11. 14 CFR 152.609 - Energy conservation practices.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Energy conservation practices. 152.609... (CONTINUED) AIRPORTS AIRPORT AID PROGRAM Energy Conservation in Airport Aid Program § 152.609 Energy conservation practices. Each sponsor shall require fuel and energy conservation practices in the operation and...

  12. 14 CFR 152.609 - Energy conservation practices.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Energy conservation practices. 152.609... (CONTINUED) AIRPORTS AIRPORT AID PROGRAM Energy Conservation in Airport Aid Program § 152.609 Energy conservation practices. Each sponsor shall require fuel and energy conservation practices in the operation and...

  13. Prebiotic synthesis and reactions of nucleosides and nucleotides

    NASA Technical Reports Server (NTRS)

    Ferris, J. P.; Yanagawa, H.; Hagan, W. J., Jr.

    1983-01-01

    The potential of diiminosuccinonitrile (DISN) as a prebiotic phosphorylating agent is studied. This compound is formed readily by the oxidation of diaminomaleonitrile, a tetramer of HCN. DISN is shown to produce the cyclization of 3'-adenosine monophosphate to adenosine 2',3'-cyclic phosphate in up to 40 percent yield. The DISN-mediated phosphorylation of uridine to uridine monophosphate is determined not to proceed efficiently in aqueous solution. The reaction of DISN and BrCN with uridine-5'-phosphate and uridine is found to result in the formation of 2,2'-anhydronucleotides and 2,2'-anhydronucleosides, respectively, and other reaction products resulting from an initial reaction at the 2' and 3'-hydroxyl groups. Homoionic montmorillonites were employed to study the clay mineral catalysis of the cyclization of adenosine-3'-phosphate.

  14. A fungal perspective on conservation biology.

    PubMed

    Heilmann-Clausen, Jacob; Barron, Elizabeth S; Boddy, Lynne; Dahlberg, Anders; Griffith, Gareth W; Nordén, Jenni; Ovaskainen, Otso; Perini, Claudia; Senn-Irlet, Beatrice; Halme, Panu

    2015-02-01

    Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem-based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature. © 2014 Society for Conservation Biology.

  15. NMR solution structure of poliovirus uridylyated peptide linked to the genome (VPgpU)

    PubMed Central

    Schein, Catherine H.; Oezguen, Numan; van der Heden van Noort, Gerbrand J.; Filippov, Dmitri V.; Paul, Aniko; Kumar, Eric; Braun, Werner

    2010-01-01

    Picornaviruses have a 22–24 amino acid peptide, VPg, bound covalently at the 5’ end of their RNA, that is essential for replication. VPgs are uridylylated at a conserved Tyrosine to form VPgpU, the primer of RNA synthesis by the viral polymerase. This first complete structure for any uridylylated VPg, of poliovirus type 1 (PV1)-VPgpU, shows that conserved amino acids in VPg stabilize the bound UMP, with the uridine atoms involved in base pairing and chain elongation projected outward. Comparing this structure to PV1-VPg and partial structures of VPg/VPgpU from other picornaviruses suggests that enteroviral polymerases require a more stable VPg structure than does the distantly related aphthovirus, foot and mouth disease virus (FMDV). The glutamine residue at the C-terminus of PV1-VPgpU lies in back of the uridine base and may stabilize its position during chain elongation and/or contribute to base specificity. Under in vivo-like conditions with the authentic cre(2C) hairpin RNA and Mg++, 5-methylUTP cannot compete with UTP for VPg uridylyation in an in vitro uridylyation assay, but both nucleotides are equally incorporated by PV1-polymerase with Mn++ and a poly-A RNA template. This indicates the 5 position is recognized under in vivo conditions. The compact VPgpU structure docks within the active site cavity of the PV-polymerase, close to the position seen for the fragment of FMDV-VPgpU with its polymerase. This structure could aid in design of novel enterovirus inhibitors, and stabilization upon uridylylation may also be pertinent for post-translational uridylylation reactions that underlie other biological processes. PMID:20441784

  16. Dynamic characterization and single-frequency cancellation performance of SMASH (SMA actuated stabilizing handgrip)

    NASA Astrophysics Data System (ADS)

    Pathak, Anupam; Brei, Diann; Luntz, Jonathan; LaVigna, Chris; Kwatny, Harry

    2008-03-01

    In urban combat environments where it is common to have unsupported firing positions, wobble significantly decreases shooting accuracy reducing mission effectiveness and soldier survivability. The SMASH (SMA Stabilizing Handgrip) has been developed to cancel wobble using antagonistic SMA actuators which reduce weight and size relative to conventional actuation, but lead to interesting control challenges. This paper presents the specification and design of the SMA actuation system for the SMASH platform along with experimental validation of the actuation and cancellation authority on the benchtop and on an M16 platform. Analytical dynamic weapon models and shooter experiments were conducted to define actuation frequency and amplitude specifications. The SMASH, designed to meet these, was experimentally characterized from the bounding quasi-static case up to the 3 Hz range, successfully generating the +/-2 mm amplitude requirement. To effectively cancel wobble it is critical to produce the proper output functional shape which is difficult for SMA due to inherent nonlinearities, hysteresis, etc. Three distinct electrical heating input functions (square, ramp, and preheat) were investigated to shape the actuator output to produce smooth sinusoidal motion. The effect of each of these functions on the cancellation response of the SMASH applied to the M16 platform was experimentally studied across the wobble range (1-3 Hz) demonstrating significant cancellation, between 50-97% depending on the smoothing function and frequency. These results demonstrate the feasibility of a hand-held wobble cancellation device providing an important foundation for future work in overall system optimization and the development of physically based feed-forward signals for closed-loop control.

  17. The Nature Conservancy's Gulf Wings Project – A Case Study in Conservation Planning for Migratory Birds

    Treesearch

    Charles Duncan; Becky Abel; Danny Kwan; David Mehlman

    2005-01-01

    The Nature Conservancy has adopted a framework for mission success called Conservation by Design. We plan at the ecoregional level to define conservation targets and the portfolio of sites needed to protect them. We consider threats and strategies for abating them at these key sites, and we define measures of success to hold ourselves accountable. Migratory birds...

  18. Inhibition, Conflict Detection, and Number Conservation

    ERIC Educational Resources Information Center

    Lubin, Amélie; Simon, Grégory; Houdé, Olivier; De Neys, Wim

    2015-01-01

    The acquisition of number conservation is a critical step in children's numerical and mathematical development. Classic developmental studies have established that children's number conservation is often biased by misleading intuitions. However, the precise nature of these conservation errors is not clear. A key question is whether conservation…

  19. The NASA Energy Conservation Program

    NASA Technical Reports Server (NTRS)

    Gaffney, G. P.

    1977-01-01

    Large energy-intensive research and test equipment at NASA installations is identified, and methods for reducing energy consumption outlined. However, some of the research facilities are involved in developing more efficient, fuel-conserving aircraft, and tradeoffs between immediate and long-term conservation may be necessary. Major programs for conservation include: computer-based systems to automatically monitor and control utility consumption; a steam-producing solid waste incinerator; and a computer-based cost analysis technique to engineer more efficient heating and cooling of buildings. Alternate energy sources in operation or under evaluation include: solar collectors; electric vehicles; and ultrasonically emulsified fuel to attain higher combustion efficiency. Management support, cooperative participation by employees, and effective reporting systems for conservation programs, are also discussed.

  20. 18 CFR 806.25 - Water conservation standards.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Water conservation standards. 806.25 Section 806.25 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN COMMISSION REVIEW AND APPROVAL OF PROJECTS Standards for Review and Approval § 806.25 Water conservation...

  1. 7 CFR 764.231 - Conservation loan uses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... timber management, erosion control, or shelter belt purposes; (3) The installation of water conservation... 7 Agriculture 7 2013-01-01 2013-01-01 false Conservation loan uses. 764.231 Section 764.231... AGRICULTURE SPECIAL PROGRAMS DIRECT LOAN MAKING Conservation Loan Program § 764.231 Conservation loan uses. (a...

  2. 7 CFR 764.231 - Conservation loan uses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... timber management, erosion control, or shelter belt purposes; (3) The installation of water conservation... 7 Agriculture 7 2014-01-01 2014-01-01 false Conservation loan uses. 764.231 Section 764.231... AGRICULTURE SPECIAL PROGRAMS DIRECT LOAN MAKING Conservation Loan Program § 764.231 Conservation loan uses. (a...

  3. 78 FR 64067 - Energy Conservation Program for Consumer Products: Energy Conservation Standards for Residential...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ...Pursuant to the Energy Policy and Conservation Act of 1975 (EPCA), as amended, the U.S. Department of Energy (DOE) must prescribe energy conservation standards for various consumer products and certain commercial and industrial equipment, including residential furnace fans. EPCA requires DOE to determine whether such standards would be technologically feasible and economically justified, and would save a significant amount of energy. In this notice, DOE is proposing new energy conservation standards for residential furnace fans. The notice also announces a public meeting to receive comment on these proposed standards and associated analyses and results.

  4. Conservation reaches new heights.

    PubMed

    Pepall, J; Khanal, P

    1992-10-01

    The conservation program with the management assistance of the Woodlands Mountain Institute in 2 contiguous parks, the Mount Everest National Park in Nepal and the Qomolangma Nature Reserve in China, in 2 countries is described. The focus is on conservation of the complex ecosystem with sustainable development by showing local people how to benefit from the park without environmental damage. Cultural diversity is as important as biological diversity. The area has been designated by UNESCO as a World Heritage Site with the "last pure ecological seed" of the Himalayas. The regional geography and culture are presented. Population growth has impacted natural resources through overgrazing, cultivation of marginal land, and deforestation; future plans to build a dam and road bordering the nature reserve pose other threats. Proposed management plans for the Makalu-Barun Nature Park (established in November 1991) and Conservation Area include a division of the park into nature reserve areas free of human activity, protected areas which permit traditional land use, and special sites and trail for tourists and religious pilgrims. The conservation area will act as a buffer for the park and provide economic opportunities; further subdivisions include land use for biodiversity protection, community forest and pasture, agroforestry, and agriculture and settlement. Efforts will be made to increase the welfare of women and local people; proposed projects include the introduction of higher milk-producing animals for stall feeding. Also proposed is a cultural and natural history museum. 70% of the project's resources will be directed to local community participation in consultation and park maintenance. The project is a model of how conservation and protection of natural resources can coexist with local economic development and participation; an integration of preservation of biological diversity, mountain wisdom, and the value of local people as resources for conservation.

  5. Conservation Action Planning: Lessons learned from the St. Marys River watershed biodiversity conservation planning process

    USGS Publications Warehouse

    Patterson, Tamatha A.; Grundel, Ralph

    2014-01-01

    Conservation Action Planning (CAP) is an adaptive management planning process refined by The Nature Conservancy (TNC) and embraced worldwide as the Open Standards for the Practice of Conservation. The CAP process facilitates open, multi-institutional collaboration on a common conservation agenda through organized actions and quantified results. While specifically designed for conservation efforts, the framework is adaptable and flexible to multiple scales and can be used for any collaborative planning effort. The CAP framework addresses inception; design and development of goals, measures, and strategies; and plan implementation and evaluation. The specific components of the CAP include defining the project scope and conservation targets; assessing the ecological viability; ascertaining threats and surrounding situation; identifying opportunities and designing strategies for action; and implementing actions and monitoring results. In 2007, TNC and a multidisciplinary graduate student team from the University of Michigan's School of Natural Resources and Environment initiated a CAP for the St. Marys River, the connecting channel between Lake Superior and Lake Huron, and its local watershed. The students not only gained experience in conservation planning, but also learned lessons that notably benefited the CAP process and were valuable for any successful collaborative effort—a dedicated core team improved product quality, accelerated the timeline, and provided necessary support for ongoing efforts; an academic approach in preparation for engagement in the planning process brought applicable scientific research to the forefront, enhanced workshop facilitation, and improved stakeholder participation; and early and continuous interactions with regional stakeholders improved cooperation and built a supportive network for collaboration.

  6. Speyeria (Lepidoptera: Nymphalidae) Conservation.

    PubMed

    Sims, Steven R

    2017-04-25

    Speyeria (Nymphalidae) are a conspicuous component of the North American butterfly fauna. There are approximately 16 species and >100 associated subspecies (or geographical variants). Speyeria are univoltine, occupy a wide range of habitats, overwinter as first instar larvae, and feed only on native violets. Speyeria species have become a model group for studies of evolution, speciation, and conservation. Several species and subspecies are threatened or endangered. The reasons for this vary with the taxa involved, but always involve the degradation or loss of quality habitat for larvae and adults. The impacts of climate change must be considered among the causes for habitat degradation and in the establishment of conservation measures. In addition to increasing the available habitat, conservation efforts should consider maintaining habitat in a seral "disturbed" successional stage that selectively favors the growth of violets and preferred adult nectar sources. A major future challenge will be determining the most effective allocation of conservation resources to those species and subspecies that have the greatest potential to respond favorably to these efforts.

  7. Speyeria (Lepidoptera: Nymphalidae) Conservation

    PubMed Central

    Sims, Steven R.

    2017-01-01

    Speyeria (Nymphalidae) are a conspicuous component of the North American butterfly fauna. There are approximately 16 species and >100 associated subspecies (or geographical variants). Speyeria are univoltine, occupy a wide range of habitats, overwinter as first instar larvae, and feed only on native violets. Speyeria species have become a model group for studies of evolution, speciation, and conservation. Several species and subspecies are threatened or endangered. The reasons for this vary with the taxa involved, but always involve the degradation or loss of quality habitat for larvae and adults. The impacts of climate change must be considered among the causes for habitat degradation and in the establishment of conservation measures. In addition to increasing the available habitat, conservation efforts should consider maintaining habitat in a seral “disturbed” successional stage that selectively favors the growth of violets and preferred adult nectar sources. A major future challenge will be determining the most effective allocation of conservation resources to those species and subspecies that have the greatest potential to respond favorably to these efforts. PMID:28441319

  8. Social-psychological principles of community-based conservation and conservancy motivation: attaining goals within an autonomy-supportive environment.

    PubMed

    Decaro, Daniel; Stokes, Michael

    2008-12-01

    Community-based natural resource conservation programs in developing nations face many implementation challenges underpinned by social-psychological mechanisms. One challenge is garnering local support in an economically and socially sustainable fashion despite economic hardship and historical alienation from local resources. Unfortunately, conservationists' limited understanding of the social-psychological mechanisms underlying participatory conservation impedes the search for appropriate solutions. We address this issue by revealing key underlying social-psychological mechanisms of participatory conservation. Different administrative designs create social atmospheres that differentially affect endorsement of conservation goals. Certain forms of endorsement may be less effective motivators and less economically and socially sustainable than others. From a literature review we found that conservation initiatives endorsed primarily for nonautonomous instrumental reasons, such as to avoid economic fines or to secure economic rewards, are less motivating than those endorsed for autonomous reasons, such as for the opportunity for personal expression and growth. We suggest that successful participatory programs promote autonomous endorsement of conservation through an administrative framework of autonomy support-free and open democratic participation in management, substantive recognition and inclusion of local stakeholder identity, and respectful, noncoercive social interaction. This framework of the autonomy-supportive environment (self-determination theory) has important implications for future research into program design and incentive-based conservation and identifies a testable social-psychological theory of conservancy motivation.

  9. New opportunities for bird conservation research

    Treesearch

    Ellen Paul; Robert J. Cooper

    2005-01-01

    It is accepted and acknowledged that effective conservation requires a scientific basis, and it is accepted and acknowledged that scientific research benefits conservation. However, there has been little effort to bring together the resources of the research communities— both academic and government-based—with the conservation planning and...

  10. 77 FR 16769 - Energy Conservation Program for Certain Industrial Equipment: Energy Conservation Standards and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-22

    ... Conservation Program for Certain Industrial Equipment: Energy Conservation Standards and Test Procedures for...-Conditioning Engineers (ASHRAE)/Illuminating Engineering Society of North America (IESNA) Standard 90.1-2010... Industrial Equipment, which includes the commercial heating, air-conditioning, and water-heating equipment...

  11. ECP (Environmental Conservation Project) Report, No. 5, March 1976. Planning for Energy Conservation.

    ERIC Educational Resources Information Center

    Environmental Law Inst., Washington, DC.

    The culmination of the Environmental Law Institute's Energy Conservation Project will be a series of handbooks addressed to state and local officials, legislators, and interested citizens setting out suggested strategies for conserving energy. This issue of the ECP Report publishes the first of a series of draft chapters from these handbooks - a…

  12. Conservation of Mexican wetlands: role of the North American Wetlands Conservation Act

    USGS Publications Warehouse

    Wilson, M.H.; Ryan, D.A.

    1997-01-01

    Mexico's wetlands support a tremendous biological diversity and provide significant natural resource benefits to local communities. Because they are also critical stopover and wintering grounds for much of North America's waterfowl and other migratory birds, Mexico has become an important participant in continental efforts to conserve these resources through the North American Wetlands Conservation Act. Funding from the Act has supported partnerships in a number of Mexico's priority wetlands to conduct data analyses and dissemination, mapping, environmental education, wetland restoration, development of sustainable economic alternatives for local people, and reserve planning and management. These partnerships, with the close involvement of Mexico's Federal Government authority, the Instituto Nacional de Ecologia, have advanced conservation in a uniquely Mexican model that differs from that employed in the United States and Canada.

  13. Robust network design for multispecies conservation

    Treesearch

    Ronan Le Bras; Bistra Dilkina; Yexiang Xue; Carla P. Gomes; Kevin S. McKelvey; Michael K. Schwartz; Claire A. Montgomery

    2013-01-01

    Our work is motivated by an important network design application in computational sustainability concerning wildlife conservation. In the face of human development and climate change, it is important that conservation plans for protecting landscape connectivity exhibit certain level of robustness. While previous work has focused on conservation strategies that result...

  14. Future battlegrounds for conservation under global change

    PubMed Central

    Lee, Tien Ming; Jetz, Walter

    2008-01-01

    Global biodiversity is under significant threat from the combined effects of human-induced climate and land-use change. Covering 12% of the Earth's terrestrial surface, protected areas are crucial for conserving biodiversity and supporting ecological processes beneficial to human well-being, but their selection and design are usually uninformed about future global change. Here, we quantify the exposure of the global reserve network to projected climate and land-use change according to the Millennium Ecosystem Assessment and set these threats in relation to the conservation value and capacity of biogeographic and geopolitical regions. We find that geographical patterns of past human impact on the land cover only poorly predict those of forecasted change, thus revealing the inadequacy of existing global conservation prioritization templates. Projected conservation risk, measured as regional levels of land-cover change in relation to area protected, is the greatest at high latitudes (due to climate change) and tropics/subtropics (due to land-use change). Only some high-latitude nations prone to high conservation risk are also of high conservation value, but their high relative wealth may facilitate additional conservation efforts. In contrast, most low-latitude nations tend to be of high conservation value, but they often have limited capacity for conservation which may exacerbate the global biodiversity extinction crisis. While our approach will clearly benefit from improved land-cover projections and a thorough understanding of how species range will shift under climate change, our results provide a first global quantitative demonstration of the urgent need to consider future environmental change in reserve-based conservation planning. They further highlight the pressing need for new reserves in target regions and support a much extended ‘north–south’ transfer of conservation resources that maximizes biodiversity conservation while mitigating global climate

  15. Conservation Presentation.

    ERIC Educational Resources Information Center

    Friday, Gerald

    2001-01-01

    Introduces a project in which students teach about the importance of recycling and conservation by presenting demonstrations. Includes demonstrations on water, plastic, and other recycling products such as steel. (YDS)

  16. The Conservation Effects Assessment Project (CEAP): a national scale natural resources and conservation needs assessment and decision support tool

    NASA Astrophysics Data System (ADS)

    Johnson, M.-V. V.; Norfleet, M. L.; Atwood, J. D.; Behrman, K. D.; Kiniry, J. R.; Arnold, J. G.; White, M. J.; Williams, J.

    2015-07-01

    The Conservation Effects Assessment Project (CEAP) was initiated to quantify the impacts of agricultural conservation practices at the watershed, regional, and national scales across the United States. Representative cropland acres in all major U.S. watersheds were surveyed in 2003-2006 as part of the seminal CEAP Cropland National Assessment. Two process-based models, the Agricultural Policy Environmental eXtender(APEX) and the Soil Water Assessment Tool (SWAT), were applied to the survey data to provide a quantitative assessment of current conservation practice impacts, establish a benchmark against which future conservation trends and efforts could be measured, and identify outstanding conservation concerns. The flexibility of these models and the unprecedented amount of data on current conservation practices across the country enabled Cropland CEAP to meet its Congressional mandate of quantifying the value of current conservation practices. It also enabled scientifically grounded exploration of a variety of conservation scenarios, empowering CEAP to not only inform on past successes and additional needs, but to also provide a decision support tool to help guide future policy development and conservation practice decision making. The CEAP effort will repeat the national survey in 2015-2016, enabling CEAP to provide analyses of emergent conservation trends, outstanding needs, and potential costs and benefits of pursuing various treatment scenarios for all agricultural watersheds across the United States.

  17. Understanding conservationists' perspectives on the new-conservation debate.

    PubMed

    Holmes, George; Sandbrook, Chris; Fisher, Janet A

    2017-04-01

    A vibrant debate about the future direction of biodiversity conservation centers on the merits of the so-called new conservation. Proponents of the new conservation advocate a series of positions on key conservation ideas, such as the importance of human-dominated landscapes and conservation's engagement with capitalism. These have been fiercely contested in a debate dominated by a few high-profile individuals, and so far there has been no empirical exploration of existing perspectives on these issues among a wider community of conservationists. We used Q methodology to examine empirically perspectives on the new conservation held by attendees at the 2015 International Congress for Conservation Biology (ICCB). Although we identified a consensus on several key issues, 3 distinct positions emerged: in favor of conservation to benefit people but opposed to links with capitalism and corporations, in favor of biocentric approaches but with less emphasis on wilderness protection than prominent opponents of new conservation, and in favor of the published new conservation perspective but with less emphasis on increasing human well-being as a goal of conservation. Our results revealed differences between the debate on the new conservation in the literature and views held within a wider, but still limited, conservation community and demonstrated the existence of at least one viewpoint (in favor of conservation to benefit people but opposed to links with capitalism and corporations) that is almost absent from the published debate. We hope the fuller understanding we present of the variety of views that exist but have not yet been heard, will improve the quality and tone of debates on the subject. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  18. Multispecies genetic objectives in spatial conservation planning.

    PubMed

    Nielsen, Erica S; Beger, Maria; Henriques, Romina; Selkoe, Kimberly A; von der Heyden, Sophie

    2017-08-01

    Growing threats to biodiversity and global alteration of habitats and species distributions make it increasingly necessary to consider evolutionary patterns in conservation decision making. Yet, there is no clear-cut guidance on how genetic features can be incorporated into conservation-planning processes, despite multiple molecular markers and several genetic metrics for each marker type to choose from. Genetic patterns differ between species, but the potential tradeoffs among genetic objectives for multiple species in conservation planning are currently understudied. We compared spatial conservation prioritizations derived from 2 metrics of genetic diversity (nucleotide and haplotype diversity) and 2 metrics of genetic isolation (private haplotypes and local genetic differentiation) in mitochondrial DNA of 5 marine species. We compared outcomes of conservation plans based only on habitat representation with plans based on genetic data and habitat representation. Fewer priority areas were selected for conservation plans based solely on habitat representation than on plans that included habitat and genetic data. All 4 genetic metrics selected approximately similar conservation-priority areas, which is likely a result of prioritizing genetic patterns across a genetically diverse array of species. Largely, our results suggest that multispecies genetic conservation objectives are vital to creating protected-area networks that appropriately preserve community-level evolutionary patterns. © 2016 Society for Conservation Biology.

  19. 75 FR 19296 - Energy Conservation Program: Test Procedures and Energy Conservation Standards for Residential...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-14

    ... Procedures and Energy Conservation Standards for Residential Furnaces and Boilers AGENCY: Office of Energy... supplemental notice of proposed rulemaking (SNOPR) to amend the test procedures for furnaces and boilers, and... Procedures for Residential Furnaces and Boilers'' or ``NOPM for Energy Conservation Standards for Residential...

  20. Conservation Genetics of the Philippine Tarsier: Cryptic Genetic Variation Restructures Conservation Priorities for an Island Archipelago Primate

    PubMed Central

    Brown, Rafe M.; Weghorst, Jennifer A.; Olson, Karen V.; Duya, Mariano R. M.; Barley, Anthony J.; Duya, Melizar V.; Shekelle, Myron; Neri-Arboleda, Irene; Esselstyn, Jacob A.; Dominy, Nathaniel J.; Ong, Perry S.; Moritz, Gillian L.; Luczon, Adrian; Diesmos, Mae Lowe L.; Diesmos, Arvin C.; Siler, Cameron D.

    2014-01-01

    Establishment of conservation priorities for primates is a particular concern in the island archipelagos of Southeast Asia, where rates of habitat destruction are among the highest in the world. Conservation programs require knowledge of taxonomic diversity to ensure success. The Philippine tarsier is a flagship species that promotes environmental awareness and a thriving ecotourism economy in the Philippines. However, assessment of its conservation status has been impeded by taxonomic uncertainty, a paucity of field studies, and a lack of vouchered specimens and genetic samples available for study in biodiversity repositories. Consequently, conservation priorities are unclear. In this study we use mitochondrial and nuclear DNA to empirically infer geographic partitioning of genetic variation and to identify evolutionarily distinct lineages for conservation action. The distribution of Philippine tarsier genetic diversity is neither congruent with expectations based on biogeographical patterns documented in other Philippine vertebrates, nor does it agree with the most recent Philippine tarsier taxonomic arrangement. We identify three principal evolutionary lineages that do not correspond to the currently recognized subspecies, highlight the discovery of a novel cryptic and range-restricted subcenter of genetic variation in an unanticipated part of the archipelago, and identify additional geographically structured genetic variation that should be the focus of future studies and conservation action. Conservation of this flagship species necessitates establishment of protected areas and targeted conservation programs within the range of each genetically distinct variant of the Philippine tarsier. PMID:25136854

  1. Delineating Focus Areas for Bird Conservation in the Central Hardwoods Bird Conservation Region

    Treesearch

    Jane A. Fitzgerald; C. Diane True; David D. Diamond; Troy Ettel; Laurel Moore; Timothy A. Nigh; Shawchyi Vorisek; Greg Wathen

    2005-01-01

    This paper reports on a process used to identify landscape-scale focus areas for the conservation of priority grassland, grass-shrubland, wetland and forest-woodland birds in the Central Hardwoods Bird Conservation Region (CHBCR). The areas were delineated by biologists and other technical staff of partner agencies and organizations in the CHBCR with the use of...

  2. Global Conservation Priorities for Marine Turtles

    PubMed Central

    Wallace, Bryan P.; DiMatteo, Andrew D.; Bolten, Alan B.; Chaloupka, Milani Y.; Hutchinson, Brian J.; Abreu-Grobois, F. Alberto; Mortimer, Jeanne A.; Seminoff, Jeffrey A.; Amorocho, Diego; Bjorndal, Karen A.; Bourjea, Jérôme; Bowen, Brian W.; Briseño Dueñas, Raquel; Casale, Paolo; Choudhury, B. C.; Costa, Alice; Dutton, Peter H.; Fallabrino, Alejandro; Finkbeiner, Elena M.; Girard, Alexandre; Girondot, Marc; Hamann, Mark; Hurley, Brendan J.; López-Mendilaharsu, Milagros; Marcovaldi, Maria Angela; Musick, John A.; Nel, Ronel; Pilcher, Nicolas J.; Troëng, Sebastian; Witherington, Blair; Mast, Roderic B.

    2011-01-01

    Where conservation resources are limited and conservation targets are diverse, robust yet flexible priority-setting frameworks are vital. Priority-setting is especially important for geographically widespread species with distinct populations subject to multiple threats that operate on different spatial and temporal scales. Marine turtles are widely distributed and exhibit intra-specific variations in population sizes and trends, as well as reproduction and morphology. However, current global extinction risk assessment frameworks do not assess conservation status of spatially and biologically distinct marine turtle Regional Management Units (RMUs), and thus do not capture variations in population trends, impacts of threats, or necessary conservation actions across individual populations. To address this issue, we developed a new assessment framework that allowed us to evaluate, compare and organize marine turtle RMUs according to status and threats criteria. Because conservation priorities can vary widely (i.e. from avoiding imminent extinction to maintaining long-term monitoring efforts) we developed a “conservation priorities portfolio” system using categories of paired risk and threats scores for all RMUs (n = 58). We performed these assessments and rankings globally, by species, by ocean basin, and by recognized geopolitical bodies to identify patterns in risk, threats, and data gaps at different scales. This process resulted in characterization of risk and threats to all marine turtle RMUs, including identification of the world's 11 most endangered marine turtle RMUs based on highest risk and threats scores. This system also highlighted important gaps in available information that is crucial for accurate conservation assessments. Overall, this priority-setting framework can provide guidance for research and conservation priorities at multiple relevant scales, and should serve as a model for conservation status assessments and priority-setting for

  3. Aspartate Carbamyltransferase : Site of End-Product Inhibition of the Orotate Pathway in Intact Cells of Cucurbita pepo.

    PubMed

    Lovatt, C J; Cheng, A H

    1984-07-01

    Lovatt et al. (1979 Plant Physiol 64: 562-569) have previously demonstrated that end-product inhibition functions as a mechanism regulating the activity of the orotic acid pathway in intact cells of roots excised from 2-day-old squash plants (Cucurbita pepo L. cv Early Prolific Straightneck). Uridine (0.5 millimolar final concentration) or one of its metabolites inhibited the incorporation of NaH(14)CO(3), but not [(14)C]carbamylaspartate or [(14)C]orotic acid, into uridine nucleotides (SigmaUMP). Thus, regulation of de novo pyrimidine biosynthesis was demonstrated to occur at one or both of the first two reactions of the orotic acid pathway, those catalyzed by carbamylphosphate synthetase (CPSase) and aspartate carbamyltransferase (ACTase). The results of the present study provide evidence that ACTase alone is the site of feedback control by added uridine or one of its metabolites. Evidence demonstrating regulation of the orotic acid pathway by end-product inhibition at ACTase, but not at CPSase, includes the following observations: (a) addition of uridine (0.5 millimolar final concentration) inhibited the incorporation of NaH(14)CO(3) into SigmaUMP by 80% but did not inhibit the incorporation of NaH(14)CO(3) into arginine; (b) inhibition of the orotate pathway by added uridine was not reversed by supplying exogenous ornithine (5 millimolar final concentration), while the incorporation of NaH(14)CO(3) into arginine was stimulated more than 15-fold when both uridine and ornithine were added; (c) incorporation of NaH(14)CO(3) into arginine increased, with or without added ornithine when the de novo pyrimidine pathway was inhibited by added uridine; and (d) in assays employing cell-free extracts prepared from 2-day-old squash roots, the activity of ACTase, but not CPSase, was inhibited by added pyrimidine nucleotides.

  4. Feedbacks between conservation and social-ecological systems

    PubMed Central

    Miller, Brian W.; Caplow, Susan C.; Leslie, Paul W.

    2012-01-01

    Robust ways to meet objectives of environmental conservation and social and economic development remain elusive. This struggle may in part be related to insufficient understanding of the feedbacks between conservation initiatives and social-ecological systems, specifically, the ways in which conservation initiatives result in social changes that have secondary effects on the environments targeted by conservation. To explore this idea we sampled peer-reviewed articles addressing the social and environmental dimensions of conservation and coded each paper according to its research focus and characterization of these feedbacks. The majority of articles in our sample focused either on the effect of conservation initiatives on people (e.g., relocation, employment) or the effect of people on the environment (e.g., fragmentation, conservation efficacy of traditional management systems). Few studies in our sample empirically addressed both the social dynamics resulting from conservation initiatives and subsequent environmental effects. In many cases, one was measured and the other was discussed anecdotally. Among the studies that describe feedbacks between social and environmental variables, there was more evidence of positive (amplifying) feedbacks between social and environmental outcomes (i.e., undesirable social outcomes yielded undesirable environmental effects, and desirable social outcomes yielded desirable environmental effects). The major themes within the sampled literature include conflict between humans and wild animals, social movements, adaptive comanagement, loss of traditional management systems, traditional ecological knowledge, human displacement and risks to livelihoods, and conservation and development. The narratives associated with each theme can serve as hypotheses for facilitating further discussion about conservation issues and for catalyzing future studies of the feedbacks between conservation and social-ecological systems. PMID:22443128

  5. Water Conservation and Water Storage

    NASA Astrophysics Data System (ADS)

    Narayanan, M.

    2014-12-01

    Water storage can be a viable part of the solution to water conservation. This means that we should include reservoirs. Regardless, one should evaluate all aspects of water conservation principles. Recent drought in California indicates that there is an urgent need to re-visit the techniques used to maintain the water supply-chain mechanism in the entire state. We all recognize the fact that fish and wildlife depend on the streams, rivers and wetlands for survival. It is a well-known fact that there is an immediate need to provide solid protection to all these resources. Laws and regulations should help meet the needs of natural systems. Farmers may be forced to drilling wells deeper than ever. But, they will be eventually depleting groundwater reserves. Needless to say that birds, fish and wildlife cannot access these groundwater table. California is talking a lot about conservation. Unfortunately, the conservation efforts have not established a strong visible hold. The Environmental Protection Agency has a plan called E2PLAN (Narayanan, 2012). It is EPA's plan for achieving energy and environmental performance, leadership, accountability, and carbon neutrality. In June 2011, the EPA published a comprehensive, multi-year planning document called Strategic Sustainability Performance Plan. The author has previously reported these in detail at the 2012 AGU fall meeting. References: Ziegler, Jay (15 JUNE 2014). The Conversation: Water conservation efforts aren't taking hold, but there are encouraging signs. THE SACRAMENTO BEE. California. Narayanan, Mysore. (2012). The Importance of Water Conservation in the 21st Century. 72nd AGU International Conference. Eos Transactions: American Geophysical Union, Vol. 92, No. 56, Fall Meeting Supplement, 2012. H31I - 1255.http://www.sacbee.com/2014/06/15/6479862/jay-ziegler-water-conservation.html#storylink=cpy

  6. Domain architecture conservation in orthologs

    PubMed Central

    2011-01-01

    Background As orthologous proteins are expected to retain function more often than other homologs, they are often used for functional annotation transfer between species. However, ortholog identification methods do not take into account changes in domain architecture, which are likely to modify a protein's function. By domain architecture we refer to the sequential arrangement of domains along a protein sequence. To assess the level of domain architecture conservation among orthologs, we carried out a large-scale study of such events between human and 40 other species spanning the entire evolutionary range. We designed a score to measure domain architecture similarity and used it to analyze differences in domain architecture conservation between orthologs and paralogs relative to the conservation of primary sequence. We also statistically characterized the extents of different types of domain swapping events across pairs of orthologs and paralogs. Results The analysis shows that orthologs exhibit greater domain architecture conservation than paralogous homologs, even when differences in average sequence divergence are compensated for, for homologs that have diverged beyond a certain threshold. We interpret this as an indication of a stronger selective pressure on orthologs than paralogs to retain the domain architecture required for the proteins to perform a specific function. In general, orthologs as well as the closest paralogous homologs have very similar domain architectures, even at large evolutionary separation. The most common domain architecture changes observed in both ortholog and paralog pairs involved insertion/deletion of new domains, while domain shuffling and segment duplication/deletion were very infrequent. Conclusions On the whole, our results support the hypothesis that function conservation between orthologs demands higher domain architecture conservation than other types of homologs, relative to primary sequence conservation. This supports the

  7. 77 FR 22472 - Energy Conservation Program: Energy Conservation Standards for Certain External Power Supplies...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ... Conservation Program: Energy Conservation Standards for Certain External Power Supplies; Correction AGENCY... external power supplies to re-insert a table that had been inadvertently deleted by a technical amendment... standards for all Class A external power supplies to meet. DATES: This correction is effective April 16...

  8. Assessment of USDA-NRCS Rangeland Conservation Programs: Recommendation for an Evidence-based Conservation Platform

    USDA-ARS?s Scientific Manuscript database

    The Conservation Effects Assessment Project (CEAP) was created in response to a request from the Office of Management and Budget that the U.S. Department of Agriculture - Natural Resource Conservation Service (USDA – NRCS) document the societal benefits anticipated to accrue from a major increase in...

  9. Native fish conservation areas: A vision for large-scale conservation of native fish communities

    USGS Publications Warehouse

    Williams, Jack E.; Williams, Richard N.; Thurow, Russell F.; Elwell, Leah; Philipp, David P.; Harris, Fred A.; Kershner, Jeffrey L.; Martinez, Patrick J.; Miller, Dirk; Reeves, Gordon H.; Frissell, Christopher A.; Sedell, James R.

    2011-01-01

    The status of freshwater fishes continues to decline despite substantial conservation efforts to reverse this trend and recover threatened and endangered aquatic species. Lack of success is partially due to working at smaller spatial scales and focusing on habitats and species that are already degraded. Protecting entire watersheds and aquatic communities, which we term "native fish conservation areas" (NFCAs), would complement existing conservation efforts by protecting intact aquatic communities while allowing compatible uses. Four critical elements need to be met within a NFCA: (1) maintain processes that create habitat complexity, diversity, and connectivity; (2) nurture all of the life history stages of the fishes being protected; (3) include a long-term enough watershed to provide long-term persistence of native fish populations; and (4) provide management that is sustainable over time. We describe how a network of protected watersheds could be created that would anchor aquatic conservation needs in river basins across the country.

  10. Conservation Kickstart- Catalyzing Conservation Initiatives Worldwide

    NASA Astrophysics Data System (ADS)

    Treinish, G.

    2014-12-01

    Adventurers and Scientists for Conservation (ASC) is a nonprofit organization that collects environmental data to catalyze conservation initiatives worldwide. Adventure athletes have the skills and motivation to reach the most remote corners of the world. ASC utilizes those skills to provide the scientific community with data while providing the outdoor community with purpose beyond the personal high of reaching a summit or rowing across an ocean. We carefully select projects, choosing partnerships that will maximize the impact of ASC volunteers. Each project must have a clear path to a tangible conservation outcome and demonstrate a clear need for our brand of volunteers. We partner with government agencies, universities, and independant reseachers to kickstart data collection efforts around the world. Last year, through a partnership with the Olympic National Forest, 20 volunteers from the Seattle area set up and monitored camera traps in an effort to survey for costal Pacific marten. Our work led to the species' listing as "critically imperiled" with NatureServe. A partnership with the inaugural Great Pacific Race, engaging trans-Pacific rowing teams, searched for microplastics in the Pacific Ocean as part of our ongoing microplastics campaign. In a multi-year partnership with the American Prairie Reserve (APR), ASC volunteer crews live and work on the Reserve collecting wildlife data year round. The data we obtain directly informs the Reserve's wildlife management decisions. On this project, our crews have safely and effectively navigated temperature extremes from -30 degrees to 100+ degrees while traveling in a remote location. We are currently scouting projects in the Okavango Delta of Botswana and the rainforest of Suriname where we will be able to cover large amounts of area in a short periord of time. ASC is at the crossroads of the adventure and coservation science communities. Our approach of answering specific questions by using highly skilled and

  11. Decision support frameworks and tools for conservation

    USGS Publications Warehouse

    Schwartz, Mark W.; Cook, Carly N.; Pressey, Robert L.; Pullin, Andrew S.; Runge, Michael C.; Salafsky, Nick; Sutherland, William J.; Williamson, Matthew A.

    2018-01-01

    The practice of conservation occurs within complex socioecological systems fraught with challenges that require transparent, defensible, and often socially engaged project planning and management. Planning and decision support frameworks are designed to help conservation practitioners increase planning rigor, project accountability, stakeholder participation, transparency in decisions, and learning. We describe and contrast five common frameworks within the context of six fundamental questions (why, who, what, where, when, how) at each of three planning stages of adaptive management (project scoping, operational planning, learning). We demonstrate that decision support frameworks provide varied and extensive tools for conservation planning and management. However, using any framework in isolation risks diminishing potential benefits since no one framework covers the full spectrum of potential conservation planning and decision challenges. We describe two case studies that have effectively deployed tools from across conservation frameworks to improve conservation actions and outcomes. Attention to the critical questions for conservation project planning should allow practitioners to operate within any framework and adapt tools to suit their specific management context. We call on conservation researchers and practitioners to regularly use decision support tools as standard practice for framing both practice and research.

  12. Geography of conservation spending, biodiversity, and culture.

    PubMed

    McClanahan, T R; Rankin, P S

    2016-10-01

    We used linear and multivariate models to examine the associations between geography, biodiversity, per capita economic output, national spending on conservation, governance, and cultural traits in 55 countries. Cultural traits and social metrics of modernization correlated positively with national spending on conservation. The global distribution of this spending culture was poorly aligned with the distribution of biodiversity. Specifically, biodiversity was greater in the tropics where cultures tended to spend relatively less on conservation and tended to have higher collectivism, formalized and hierarchical leadership, and weaker governance. Consequently, nations lacking social traits frequently associated with modernization, environmentalism, and conservation spending have the largest component of Earth's biodiversity. This has significant implications for setting policies and priorities for resource management given that biological diversity is rapidly disappearing and cultural traits change slowly. Therefore, we suggest natural resource management adapt to and use characteristics of existing social organization rather than wait for or promote social values associated with conservation spending. Supporting biocultural traditions, engaging leaders to increase conservation commitments, cross-national efforts that complement attributes of cultures, and avoiding interference with nature may work best to conserve nature in collective and hierarchical societies. Spending in modernized nations may be a symbolic response to a symptom of economic development and environmental degradation, and here conservation actions need to ensure that biodiversity is not being lost. © 2016 Society for Conservation Biology.

  13. 75 FR 21981 - Energy Conservation Program: Energy Conservation Standards for Residential Water Heaters, Direct...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-27

    ... DEPARTMENT OF ENERGY 10 CFR Part 430 [Docket Number EE-2006-BT-STD-0129] RIN 1904-AA90 Energy Conservation Program: Energy Conservation Standards for Residential Water Heaters, Direct Heating Equipment, and Pool Heaters Correction In rule document 2010-7611 beginning on page 20112 in the issue of Friday...

  14. Tracking channel-floodplain sediment exchange with conservative and non-conservative geochemical tracers

    NASA Astrophysics Data System (ADS)

    Belmont, Patrick; Stout, Justin

    2013-04-01

    Fine sediment is routed through landscapes and channel networks in a highly unsteady and non-uniform manner, potentially experiencing deposition and re-suspension many times during transport from source to sink. Developing a better understanding of sediment routing at the landscape scale is an intriguing challenge from a modeling perspective because it requires consideration of a multitude of processes that interact and vary in space and time. From an applied perspective, an improved understanding of sediment routing is essential for predicting how conservation and restoration practices within a watershed will influence water quality, to support land and water management decisions. Two key uncertainties in predicting sediment routing at the landscape scale are 1) determining the proportion of suspended sediment that is derived from terrestrial (soil) erosion versus channel (bank) erosion, and 2) constraining the proportion of sediment that is temporarily stored and re-suspended within the channel-floodplain complex. Sediment fingerprinting that utilizes a suite of conservative and non-conservative geochemical tracers associated with suspended sediment can provide insight regarding both of these key uncertainties. Here we present a model that tracks suspended sediment with associated conservative and non-conservative geochemical tracers. The model assumes that particle residence times are described by a bimodal distribution wherein some fraction of sediment is transported through the system in a relatively short time (< 1 year) and the remainder experiences temporary storage (of variable duration) within the channel-floodplain complex. We use the model to explore the downstream evolution of non-conservative tracers under equilibrium conditions (i.e., exchange between the channel and floodplain is allowed, but no net change in channel-floodplain storage can occur) to illustrate how the process of channel-floodplain storage and re-suspension can potentially bias

  15. Communication Skills for Conservation Professionals.

    ERIC Educational Resources Information Center

    Jacobson, Susan K.

    This book provides in-depth guidance for students, scientists, managers, and professionals in achieving conservation goals through better communication. It introduces communication approaches--marketing and mass media, citizen participation, public information, environmental interpretation, and conservation education activities--and offers scores…

  16. Remote sensing for the sustainable management and conservation of forest environments biodiversity: the conservation managers perspective.

    NASA Astrophysics Data System (ADS)

    Aguilar-Amuchas, N.; Henebry, G. M.; Blanchard, J.; Sutter, R.

    2008-12-01

    The potential use of remote sensing for the design and implementation of sustainable management, conservation, and monitoring of forest biodiversity has been well documented in the scientific literature. However, when we look into how often remote sensing is actually being used in the decision making processes affecting biodiversity conservation and sustainable management, we find that, apart from specific study cases, its use is not as widespread as we know it should. There is an enormous gap between our scientific achievements and their use in the real world towards the preservation of a rapidly vanishing biodiversity. Conservation managers understand the potential remote sensing has. However, logistical constraints and high technical skills requirements render the use of remote sensing data difficult. Sound and easy approaches need to be developed and implemented. We present two study cases that illustrate 1st. How the interaction between tropical forest managers and remote sensing specialist allowed developing a simple method for the identification of priority areas for field surveys of tropical forests management ecological sustainability indicators and, 2nd. How remote sensing is being used by The Nature Conservancy as a first level approach towards the assessment of forest conservation strategies effectiveness in for areas located in 11 states, covering different forest types and a variety of conservation objectives.

  17. Domestic water conservation potential in Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Abdulrazzak, Mohammed J.; Khan, Muhammad Z. A.

    1990-03-01

    Domestic water conservation in arid climates can result in efficient utilization of existing water supplies. The impacts of conservation measures such as the installation of water-saving devices, water metering and pricing schemes, water rationing and public awareness programs, strict plumbing codes, penalties for wasting water, programs designed to reduce leakage from public water lines and within the home, water-efficient landscaping, economic and ethical incentives are addressed in detail. Cost savings in arid climates, with particular reference to Saudi Arabia, in relation to some conservation techniques, are presented. Water conservation technology and tentative demonstration and implementation of water conservation programs are discussed.

  18. Landscape Conservation Cooperatives: Creating a Collaborative Conservation Vision in the Face of Climate Change Uncertainty

    NASA Astrophysics Data System (ADS)

    Athearn, N.; Schlafmann, D.

    2015-12-01

    The 22 Landscape Conservation Cooperatives (LCCs) form a "network of networks," each defined by the characteristics of its ecoregion and its unique community of conservation managers, practitioners, and scientists. As self-directed partnerships, LCCs are strongly influenced not only by the landscape but by the evolving cultures and values that define the multi-faceted relationships between people and place. LCCs maintain an ecologically connected network across these diverse landscapes by transcending borders and leveraging resources. Natural resource managers are challenged to make decisions in the face of multiple uncertainties, and several partners across the network have recognized that climate change is one important uncertainty that spans boundaries - both across the conservation community and beyond. The impacts of climate change across the LCC Network are likely to be as diverse as the network itself - manifesting as, for example, sea level rise, ocean acidification, loss of sea ice, and shifts in climate patterns and timing - but synergies are being leveraged within and between LCCs and national climate-focused programs to systematically address the needs of the network to support a collaborative conservation vision that addresses multiple landscape-scale stressors in the face of climate uncertainties. This vision is being achieved by leveraging the convening power of the LCCs and collaborating with DOI Climate Science Centers and others. Selected case studies will demonstrate how the network finds strength in its differences, but also reveals powerful collaborative opportunities through integrated science, shared conservation strategies, and strategic approaches for translating targeted science to conservation action. These examples exemplify past successes as well as ongoing efforts as the network continues to bring about effective application of climate science to achieve conservation outcomes across the LCC Network in an uncertain future climate.

  19. Structural variations of single and tandem mismatches in RNA duplexes: a joint MD simulation and crystal structure database analysis.

    PubMed

    Halder, Sukanya; Bhattacharyya, Dhananjay

    2012-10-04

    Internal loops within RNA duplex regions are formed by single or tandem basepairing mismatches with flanking canonical Watson-Crick basepairs on both sides. They are the most common motif observed in RNA secondary structures and play integral functional and structural roles. In this report, we have studied the structural features of 1 × 1, 2 × 2, and 3 × 3 internal loops using all-atom molecular dynamics (MD) simulation technique with explicit solvent model. As MD simulation is intricately dependent on the choice of force-field and these are often rather approximate, we have used both the most popular force-fields for nucleic acids-CHARMM27 and AMBER94-for a comparative analysis. We find that tandem noncanonical basepairs forming 2 × 2 and 3 × 3 internal loops are considerably more stable than the single mismatches forming 1 × 1 internal loops, irrespective of the force field. We have also analyzed crystal structure database to study the conservation of these helical fragments in the corresponding sets of RNA structures. We observe that the nature of stability in MD simulations mimic their fluctuating natures in crystal data sets also, probably indicating reliable natures of both the force fields to reproduce experimental results. We also notice significant structural changes in the wobble G:U basepairs present in these double helical stretches, leading to a biphasic stability for these wobble pairs to release the deformational strains introduced by internal loops within duplex regions.

  20. Building Conservation Capacity in Southeast Asia: Outcomes of the ATBC 2015 Asia-Pacific Chapter Meeting Conservation Education Symposium

    ERIC Educational Resources Information Center

    Souter, Nicholas J.; Hughes, Alice C.; Savini, Tommaso; Rao, Madhu; Goodale, Eben; Van Nice, Amy; Huang, Natalia; Liu, Jing-Xin; Hunt, Matt P.; O'Connor, David A.; Heung-Lam, Anny Li; Gnuen, Gneb; Sun, Yoeung; Silva, Inês

    2017-01-01

    The "Building Capacity for Conservation in Southeast Asia" symposium was held at the 2015 Association for Tropical Biology and Conservation, Asia-Pacific Chapter meeting. The range of programs discussed fell into three categories: career development, project-specific activities and outreach, and delivering conservation information to…