bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Metabolism of Nitrogen in Plants
Authors: Morikawa Hiromichi , Takahashi Misa , Sakamoto Atsushi , Ueda-Hashimoto Manami , Matsubara Toshiyuki , Miyawaki Kazuhiro , Kawamura Yoshifumi , Hirata Toshifumi , Suzuki Hitomi 
Published: February 2015

Abstract
Our previous study showed that approximately one-third of the nitrogen of 15N-labeled NO2 taken up into plants was converted to a previously unknown organic nitrogen (hereafter designated UN) that was not recoverable by the Kjeldahl method (Morikawa et al., 2004). In this communication, we discuss metabolic and physiological relevance of the UN based on our newest experimental results. All of the 12 plant species were found to form UN derived from NO2 (about 10-30% of the total nitrogen derived from NO2). The UN was formed also from nitrate nitrogen in various plant species. Thus, UN is a common metabolite in plants. The amount of UN derived from NO2 was greatly increased in the transgenic tobacco clone 271 (Vaucheret et al., 1992) where the activity of nitrite reductase is suppressed less than 5% of that of the wild-type plant. On the other hand, the amount of this UN was significantly decreased by the overexpression of S-nitrosoglutathione reductase (GSNOR). These findings strongly suggest that nitrite and other reactive nitrogen species are involved in the formation of the UN, and that the UN-bearing compounds are metabolizable. A metabolic scheme for the formation of UN-bearing compounds was proposed, in which nitric oxide and peroxynitrite derived from NO2 or endogenous nitrogen oxides are involved for nitrosation and/or nitration of organic compounds in the cells to form nitroso and nitro compounds, including N-nitroso and S-nitroso ones. Participation of non-symbiotic haemoglobin bearing peroxidase-like activity (Sakamoto et al., 2004) and GSNOR (Sakamoto et al., 2002) in the metabolism of the UN was discussed. The UN-bearing compounds identified to date in the extracts of the leaves of Arabidopsis thaliana fumigated with NO2 include a ⊿2- 1,2,3-thiadiazoline derivative (Miyawaki et al., 2004) and 4-nitro-β-carotene.
Tolerance to, and Uptake and Degradation of 2,4,6-Trinitrotoluene (TNT) are Enhanced by the Expression of a Bacterial Nitroreductase Gene in Arabidopsis thaliana
Authors: Kurumata Mami , Takahashi Misa , Sakamoto Atsushi , Ramos Juan L. , Nepovim Ales , Vanek Tomas , Hirata Toshifumi , Morikawa Hiromichi 
Published: February 2015

Abstract
Arabidopsis thaliana was transformed with a gene encoding a nitroreductase (NTR, E.C. 1.6.99.7) with activity against a wide range of nitroaromatic compounds. The gene was transferred from Escherichia coli by an Agrobacterium-mediated in planta method. The ob­tained seeds were sowed to produce T1 plants, and they were assayed for the integration of the transgene in the plant genome. Transgenic plants that were positive with the PCR analysis were self-pollinated to produce T2 generation plants. Seven lines obtained were assayed for the NTR activity. While the noil-transformed wild-type plants showed no detectable NTR activity, the enzyme activity of the transgenic plant lines was approx. 20 times higher. Using the line with the highest NTR activity, the phytoremediation characteristics of plants against 2,4,6-trinitrotoluene (TNT) was investigated. While the wild-type plants did not grow in the presence of 0.1 mᴍ TNT, the transgenic plants grew almost normally in this condition. The uptake of TNT by seedlings of transgenic plants increased by 7 to 8 times when they were floated on TNT solution. HPLC analysis showed that the peak due to TNT taken up into plant body was much smaller in the transgenic plants as compared with that of the wild type, and that a number of peaks attributable to the degradation products of TNT, including 4-amino-2,6-dinitrotoluene, were detected in the extract from the transgenic plants. This indi­cates that the expression of bacterial NTR improved the capability of plants to degrade TNT.
Genetic Modification of Wetland Grasses for Phytoremediation
Authors: Czakó Mihály , Feng Xianzhong , He Yuke , Liang Dali , Márton László 
Published: February 2015

Abstract
Wetland grasses and grass-like monocots are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential. Tissue culture is prerequisite for genetic manipulation, and methods are reported here for in vitro culture and micropropagation of a number of wetland plants of various ecological requirements such as salt marsh, brackish water, riverbanks, and various zones of lakes and ponds, and bogs. The monocots represent numerous genera in various families such as Poaceae, Cyperaceae, Juncaceae, and Typhaceae. The reported species are in various stages of micropropagation and Arundo donax is scaled for mass propagation for selecting elite lines for pytoremediation. Transfer of key genes for mercury phytoremediation into the salt marsh cordgrass (Spartina alterniflora) is also reported here. All but one transgenic lines contained both the organomercurial lyase (merB) and mercuric reductase (merA) sequences showing that co-introduction into Spartina of two genes from separate Agrobacterium strains is possible.
Differential Induction of Glutathione Transferases and Glucosyltransferases in Wheat, Maize and Arabidopsis thaliana by Herbicide Safeners
Authors: Edwards Robert , Buono Daniele Del , Fordham Michael , Skipsey Mark , Brazier Melissa , Dixon David P. , Cummins Ian 
Published: February 2015

Abstract
By learning lessons from weed science we have adopted three approaches to make plants more effective in phytoremediation:
1. The application of functional genomics to identify key components involved in the detoxification of, or tolerance to, xenobiotics for use in subsequent genetic engineering/breeding programmes.
2. The rational metabolic engineering of plants through the use of forced evolution of protective enzymes, or alternatively transgenesis of detoxification pathways.
3. The use of chemical treatments which protect plants from herbicide injury. In this paper we examine the regulation of the xenome by herbicide safeners, which are chemicals widely used in crop protection due to their ability to enhance herbicide selectivity in cereals. We demonstrate that these chemicals act to enhance two major groups of phase 2 detoxification enzymes, notably the glutathione transferases and glucosyltransferases, in both cereals and the model plant Arabidopsis thaliana, with the safeners acting in a chemical- and species-specific manner. Our results demonstrate that by choosing the right combination of safener and plant it should be possible to enhance the tolerance of diverse plants to a wide range of xenobiotics including pollutants.
Biodegrader Metabolic Expansion during Polyaromatic Hydrocarbons Rhizoremediation
Authors: Rugha Clayton L. , Susilawati Endang , Kravchenko Alexandra N. , Thomas John C. 
Published: February 2015

Abstract
Root-microbe interactions are considered to be the primary process of polyaromatic hydrocarbon (PAH) phytoremediation, since bacterial degradation has been shown to be the dominant pathway for environmental PAH dissipation. However, the precise mechanisms driving PAH rhizostimulation symbiosis remain largely unresolved. In this study, we assessed PAH degrading bacterial abundance in contaminated soils planted with 18 different native Michigan plant species. Phenanthrene metabolism assays suggested that each plant species differentially influenced the relative abundance of PAH biodegraders, though they generally were observed to increase heterotrophic and biodegradative cell numbers relative to unplanted soils. Further study of > 1800 phenanthrene degrading isolates indicated that most of the tested plant species stimulated biodegradation of a broader range of PAH compounds relative to the unplanted soil bacterial consortia. These observations suggest that a principal contribution of planted systems for PAH bioremediation may be via expanded metabolic range of the rhizosphere bacterial community.
The Arbuscular Mycorrhizal Status of Poplar Clones Selected for Phytoremediation of Soils Contaminated with Heavy Metals
Authors: Takács Tünde , Radimszky László , Németh Tamás 
Published: February 2015

Abstract
The aim of this work was to study the colonization of indigenous arbuscular mycorrhizal fungi (AMF) species in fine-roots of poplar clones. Roots of 7 poplar clones were sampled from a 1-year-old trial established at an industrial site strongly polluted with heavy metals at Balatonfűzfő , Hungary. The poplar clones have shown variable degrees of colonization by AMF, suggesting differential host susceptibility or mycorrhizal dependency. After outplanting the percentage of poplar survival was strongly correlated with the frequency of AMF infection. Two clones that survived at the lowest ratio after outplanting had not been colonized by AMF in contrast to those which survived to a much higher extent.
The Possible Role of Hydroxylation in the Detoxification of Atrazine in Mature Vetiver (Chrysopogon zizanioides Nash) Grown in Hydroponics
Authors: Marcacci Sylvie , Raveton Muriel , Ravanel Patrick , Schwitzguébel Jean-Paul 
Published: February 2015

The resistance mechanism of vetiver (Chrysopogon zizanioides) to atrazine was investigated to evaluate its potential for phytoremediation of environment contaminated with the herbicide. Plants known to metabolise atrazine rely on hydroxylation mediated by benzoxazinones, conjugation catalyzed by glutathione-S-transferases and dealkylation probably mediated by cytochromes P450. All three possibilities were explored in mature vetiver grown in hydroponics during this research project. Here we report on the chemical role of benzoxazinones in the transformation of atrazine.
Fresh vetiver roots and leaves were cut to extract and study their content in benzoxazinones known to hydroxylate atrazine, such as 2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)- one (DIBOA), 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA) and their mono- and di-glucosylated forms. Identification of benzoxazinones was performed by thin layer chromatography (TLC) and comparison of retention factors (Rf) and UV spectra with standards: although some products exhibited the same Rf as standards, UV spectra were different. Furthermore, in vitro hydroxylation of atrazine could not be detected in the presence of vetiver extracts. Finally, vetiver organs exposed to [14C]-atrazine did not produce any significant amount of hydroxylated products, such as hydroxyatrazine (HATR), hydroxydeethylatrazine (HDEA), and hydroxy-deisopropylatrazine (HDIA). Altogether, these metabolic features suggest that hydroxylation was not a major metabolic pathway of atrazine in vetiver.
Antioxidative Activity of New N-Oxides of Tertiary Amines: Membrane Model and Chromogen Studies
Authors: Kleszczyńska Halina , Bonarska Dorota , Pruchnik Hanna , Bielecki Krzysztof , Piasecki Andrzej , Łuczyński Jacek , Sarapuk Janusz 
Published: February 2015

Potential antioxidative activities of three series of newly synthesized N-oxides were studied. Individual components in each of the series differed in the lipophilicities and number of free radical scavenging groups. Various methods were used to determine their antioxidative efficiencies: Prevention of erythrocyte membrane lipid oxidation induced by UV irradiation and chromogen experiments in which antioxidative efficiencies of compounds were compared to that of the standard antioxidant Trolox (a water-soluble vitamin E analogue). Additionally, some hemolytic (pig erythrocytes) and differential scanning calorimetry (DSC) measurements were performed to determine a mechanism of the interaction between membranes and N-oxides.
It was found that N-oxides, especially those of long alkyl chains (> C12H25), readily interacted with both, erythrocyte and liposomal membranes. No marked differences were found in their protection of erythrocytes against oxidation. In most cases inhibition of oxidation changed between 15% and 25%. Still, it was far better than in chromogen experiments where suppression of free radicals reached 20% in the best case. It may be concluded that antioxidative capabilities of N-oxides are moderate.
Studies on the interaction mechanism showed that incorporation of particular compounds into model membranes varied. Hemolysing activities of compounds increased with the elongation of the alkyl chain but differed for corresponding compounds of particular series indicating that lipophilicity of compounds is not the only factor determing their interaction with erythrocyte membranes.
DSC experiments showed that N-oxides, upon incorporation into 1,2-dipalmitoyl-3-snphosphatidylcholine liposomes, shifted the subtransition (Tp) and the main transition (Tm). The shifts observed depended on the alkyl chain length. The effects differed for each series. It seems that in the case of long alkyl chain compounds the domain formation may take place. Generally, the decrease of Tm was greatest for the same compounds that exhibited the best hemolytic efficacy. The same conclusion concerns the decrease of cooperativity of the main transition and the observed changes suggest an increase in membrane fluidity. Both, erythrocyte and DSC experiments seem to indicate that compounds of particular series incorporate in a somewhat different way into membranes.
Selection and Characterization of ʟ-Ethionine Resistant Mutants of Trichosporon cutaneum
Authors: Georgieva Nelly , Alexieva Zlatka 
Published: February 2015

Abstract
Trichosporon cutaneum R57 and its ʟ-ethionine resistant mutant NZ94 strain were investigated. The amino acid analyses of cell content of both strains were carried out. The pool of free methionine in the mutant strain is enhanced 16.5 times. The total amount of sulphurcontaining amino acids in the mutant cells was significantly increased from 36.8 in the wild strain to 113.4 mg/g protein in the mutant strain. In the process of mutant strain cultivation there was found a high excretion of free methionine (259 μg/ml) in the medium. It was shown that the amino acid content of both wild and mutant strains would be helpful for formulating of new improved animal nutritional diets.
Synthesis and Evaluation of Demethoxyviridin Derivatives as Potential Antimicrobials
Authors: Kiran Ismail , Ilhan Semra , Akar Tamer , Tur Lacine , Erol Erdinc 
Published: February 2015

Abstract
The in vitro antibacterial and antifungal activities of demethoxyviridin and some synthetic analogues were evaluated by the agar diffusion method. The minimum inhibitory concentrations (MIC) of the active compounds were also determined by the agar dilution method. Demethoxyviridin (1) showed moderate antibacterial activity against most of the strains tested. 1α-Hydroxydemethoxyviridin (3) showed antibacterial activity and the most potent in vitro antifungal activity with MIC of 20 μg/ml (0.062 mm) against Aspergillus niger, A. fumigatus, A. flavus, A. parasiticus, Fusarium solani, F. graminarum, Geotrichum candidum whereas 5′-methylfuro-(4′,3′,2′-4,5,6)androst-5-ene-3,17-dione (7) exhibited very weak antifungal activity against Candida albicans only.
Ovipositional Deterrent on Mature Stage of Sweet Pepper, Capsicum annuum, against Liriomyza trifolii (Burgess)
Authors: Kashiwagi Takehiro , Mikagi Eriko , Mekuria Daniel Bisrat , Boru Aman Dekebo , Tebayashi Shin-ich , Kim Chul-Sa 
Published: February 2015

Abstract
Liriomyza trifolii (Burgess), the American serpentine leafminer fly, is a well-known serious pest in the world. This insect species attacks plants of more than 21 families including Solanaceae plants. A sweet pepper, Capsicum annuum (Solanaceae), on mature stage, however, shows resistance to this leafminer fly. This resistance is based on the ovipositional deterrent in the sweet pepper leaf against the fly species. Based on the bioassay guided fractionation, phytol [(2E)-3,7,11,15-tetramethyl-2-hexadecen-1-ol] was isolated and identified as an ovipositional deterrent against this insect species. The yield of this compound was 815 μg/g fresh leaf of C. annuum. This compound completely deterred the females from laying their eggs on host plant leaves treated at 35.2 μg/cm2.
Comparison of Fatty Acid Composition of Cell Homogenates and Isolated Chloroplasts in Acetabularia crenulata (Lamouroux)
Authors: Santiago-Vázquez Lory Z. , Jacobs Robert S. 
Published: February 2015

Abstract
Algal preparations from Acetabularia crenulata were analyzed for their fatty acid composition to establish the suitability of this alga as a model to study fatty acid oxidation and oxylipin biosynthesis. The work was based on two goals. The first goal of this study was to determine the contribution of fatty acids from contaminating bacteria and how this influenced the total fatty acid composition of cell homogenates of A. crenulata collected in the wild as compared to specimens cultured in sterile conditions. The major fatty acids detected for both specimens were palmitic (C16:0), palmitoleic (C16:1n-7), oleic (C18:1n-9), linoleic (C18:2n-6), linolenic (C18:3n-3), and octadecatetraenoic acid (C18:4n-3). Significant amounts of odd-chain fatty acids common to bacteria were not detected in either sample. Furthermore, branched-chain fatty acids, typical bacterial biomarkers, were not detected in either sample. Data suggest that bacteria do not greatly contribute to the total fatty acid pool of A. crenulata.
The second goal was to compare the fatty acid composition of cell homogenates with that of isolated chloroplasts. Comparatively speaking palmitoleic and octadecatetraenoic acid were found at significantly lower concentrations in the chloroplast whereas oleic and linolenic acid were found at significantly higher amounts in this organelle. Furthermore, the amount of hexadecatrienoic acid (C16:3), a fatty acid commonly esterified to monogalactosyldiacylglycerol (MGDG; lipid present at high concentrations inside the chloroplasts of algae), was present at very low concentrations in these plastids (0.7%). Typically green algal follow the “prokaryotic pathway” for MGDG biosynthesis where C18:3 is esterified at the sn-1 position of the glycerol backbone and C18:3 or C16:3 at the sn-2 position, making C16:3 a major fatty acid inside chloroplasts. Interestingly, our results suggest that chloroplasts of A. crenulata appear to follow the “eukaryotic pathway” for MGDG biosynthesis where C18:3 is both at the sn-1 and sn-2 position of MGDG. Taking into account the exceptions noted, the fatty acid composition for A. crenulata is similar to that reported for most chlorophytes.
Understanding Genetic Diversity of the Liver Fluke Fasciola hepatica
Authors: Dosay-Akbulut Mine , Trudgett Alan , Stanhope Michael 
Published: February 2015

Abstract
Economical breeding is important to obtain maximum gain from the breeding in the animal sector. The economic loss has to be eliminated or should be minimized. The liver fluke, Fasciola hepatica, present mostly in sheep and dairy cattle affect the yield of animals and even cause their death. To eliminate or minimize the impact of these parasites on the animals, it is important to understand the genetic diversity of the liver fluke populations and the relationship between parasite and host at regional bases. This research was carried out to determine diversity by sequence analysis of the mitochondrial ND1 gene and ribosomal ITS1 region.
Volatile Compounds in Shoulder Gland Secretions of Male Flying Foxes, Genus Pteropus (Pteropodidae, Chiroptera)
Authors: Wood William F. , Walsh Allyson , Seyjagat John , Weldon Paul J. 
Published: February 2015

Abstract
The shoulder gland secretions of captive males of the Indian flying fox (Pteropus giganteus), the little golden-mantled flying fox (P. pumilus), the island flying fox (P. hypomelanus), and the large flying fox (P. vampyrus) were examined by gas chromatography-mass spectrometry. Sixty-five compounds, including hydrocarbons, carboxylic acids, alcohols, aldehydes, ketones, esters, and amides, were identified among the four species. Many of these compounds, such as squalene, cholesterol, and C5-C16 straight- and branched-chain carboxylic acids, are typical of tetrapod epidermal products. Aldehydes, which were detected in all four Pteropus species, and some straight- and branched-chain ketones, which were detected in P. hypomelanus and P. pumilus, are known from other mammalian skin glands. Acetophenone, 4-acetoxyacetophenone, and 4-hydroxyacetophenone were observed in P. pumilus; the last compound comprised 37.1% of the total ion current. 2,3-Butanediol, a prominent component (5.2-19.3%) in the secretions of P. giganteus, P. hypomelanus, and P. pumilus, and C10 and C12 isopropyl esters and C10-C14 1-methylbutyl esters, observed in P. hypomelanus and P. vampyrus, have not previously been reported from vertebrates. α-Methyl-4-methoxybenzyl alcohol and dihydro-5-phenyl-2(3H)-furanone, from P. giganteus and P. pumilus, are new natural products. 1-Chloro-3-methyl-2-butene, another new natural product, and five C5 compounds exhibiting a similar isoprenoid structure were observed in P. giganteus. Striking contrasts were observed in the chemical profiles of the species we examined, with even general chemical classes differentially represented among them.
Seasonal Variation and Analgesic Properties of Different Parts from Curcuma zedoaria Roscoe (Zingiberaceae) Grown in Brazil
Authors: Pamplona Christiane Regina , Souza Marcia Maria de , Machado Marina da Silva , Filhoa Valdir Cechinel , Navarro Dionezine , Yunes Rosendo Augusto , Monache Franco Delle , Niero Rivaldo 
Published: February 2015

Abstract
This work describes the seasonal variation of curcumenol (1) and dihydrocurdione (2), two active terpenoids from different parts (roots, mother rhizome and rugous rhizome) of Curcuma zedoaria grown in Brazil. The analysis was carried out by high resolution gas chromatography, using external standards for determination. The results showed that both terpenoids are present in all the parts studied. However, C. zedoaria exhibited about three times more terpenoids in the mother rhizome in autumn than in other parts and seasons studied. The antinociceptive activity of the dichloromethane extracts from different parts and collected in different seasons was studied using the acetic acid-induced abdominal constriction model in mice. The extracts obtained from mother rhizome collected in autumn and winter at doses of 10 mg/kg body weight, i.p., caused considerable antinociceptive activity inhibiting 91.1 and 93.4% of the abdominal constrictions, respectively, whereas compounds 1 and 2 caused inhibitions of 64.0 and 46.0%, respectively. These results confirm that both compounds contribute to explain the antinociceptive effect of the plant but suggest that other compounds are also acting as analgesics