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... A procedure is described for a simple and highly sensitive quantitative assay of various sucrose and glucose ester mixtures extracted from plant tissue surfaces and of certain synthetic sugar esters of commercial importance. The method involves staining sugar esters with Rhodamine B followed by spectrophotometric detection of the "complexed" stain. The only instrumentation required consists of a c ...
... Trichome exudate compounds isolated from leaves of Nicotiana tabacum, N. glutinosa (accessions 24 and 24a), and 21 other Nicotiana species were evaluated for biorational activity against C. lagenarium, the anthracnose pathogen of cucumber. Exudate compounds tested were the cembrane diterpenes alpha and beta-4,8,13-duvatriene-1,3-diols (DVT diols); the labdane diterpenes (13-E)-labda-13-ene-8alpha, ...
... Polygalacturonate 4-alpha-galacturonosyltransferase (EC 2.4.1.43) activity has been identified in microsomal membranes isolated from tobacco (Nicotiana tabacum L. cv Samsun) cell-suspension cultures. Incubation of UDP-[14C]galacturonic acid with tobacco membranes results in a time-dependent incorporation of [14C]galacturonic acid into a chloroform-methanol-precipitable and 65% ethanol-insoluble pr ...
... Transgenic tobacco (Nicotiana tabacum L.) plants carrying a fusion between the nopaline synthase (nos) promoter and chloramphenicol acetyltransferase (CAT) reporter gene (cat) were tested for their response to treatment with H2O2. The nos promoter-driven CAT activity increased significantly by addition of H2O2, reaching the maximum level at 15 mM. Kinetic analysis for CAT activity showed that indu ...
... Apoplastic peroxidase isoenzymes from stems of Nicotiana tabacum rapidly oxidized sinapic acid and sinapyl alcohol, in addition to 4-coumaric acid, ferulic acid and coniferyl alcohol. By contrast, the peroxidase isoenzymes from stems of Vigna angularis oxidized sinapic acid and sinapyl alcohol quite slowly but rapidly oxidized compounds with a 4-hydroxyphenyl or a guaiacyl group. However, the oxid ...
... Plants respond differentially to wounding and pathogens using distinct signaling pathways, so that wound signals are transmitted to jasmonic acid (JA) which induces basic pathogenesis-related (PR) proteins, whereas pathogenic signals cause, in addition to JA, accumulation of salicylic acid (SA) which stimulates production of acidic PR proteins. Transgenic tobacco plants expressing a gene for a sma ...
Helianthus annuus; Brassica napus; measurement; chemical degradation; dose response; jasmonic acid; gene expression; Triticum aestivum; Nicotiana tabacum; esters; stereochemistry; enzyme activity; chemical structure; seed germination; transgenic plants; cotyledons; proteinase inhibitors; reporter genes; chemical constituents of plants; chlorophyll; beta-glucuronidase
Abstract:
... The importance of the two chiral centers at C-3 and C-7 in the molecular structure of jasmonic acid in plant responses was investigated. We separated methyl jasmonate (MeJA) into (3R)- and (3S)-isomers with a fixed stereochemistry at C-3, but epimerization at C-7 is possible. The four isomers of the nonepimerizable analog 7-methyl MeJA were synthesized. These six esters and their corresponding aci ...
... Reactive oxygen species are believed to perform multiple roles during plant defense and possibly as cellular signaling molecules. In animals, nitric oxide (NO) is an important redox-active signaling molecule. Here we show that infection of resistant, but not susceptible, tobacco with tobacco mosaic virus resulted in enhanced NO synthase (NOS) activity. Furthermore, administration of NO donors or r ...
... The biosynthesis of lignin monomers involves two methylation steps catalyzed by orthodiphenol-O-methyltransferases: caffeic acid/5-hydroxyferulic acid 3/5-O-methyltransferases (COMTs) and caffeoyl-coenzyme A (CoA)/5-hydroxyferuloyl-CoA 3/5-O-methyltransferases (CCoAOMTs). Two COMT classes (I and II) were already known to occur in tobacco (Nicotiana tabacum) and three distinct CCoAOMT classes have ...
... A cDNA encoding a protein with 456 amino acids whose sequence shows considerable similarity to plant acyltransferases was identified among 750 Clarkia breweri flower expressed sequence tags. The cDNA was expressed in Escherichia coli, and the protein produced was shown to encode the enzyme benzoyl-coenzyme A (CoA):benzyl alcohol benzoyl transferase (BEBT). BEBT catalyzes the formation of benzylben ...
... The anaphase promoting complex or cyclosome is the ubiquitin-ligase that targets destruction box-containing proteins for proteolysis during the cell cycle. Anaphase promoting complex or cyclosome and its activator (the fizzy and fizzy-related) proteins work together with ubiquitin-conjugating enzymes (UBCs) (E2s). One class of E2s (called E2-C) seems specifically involved in cyclin B1 degradation. ...
... Cytosolic acyl-CoA-binding proteins (ACBP) bind long-chain acyl-CoAs and act as intracellular acyl-CoA transporters and maintain acyl-CoA pools. Arabidopsis thaliana ACBP2 shows conservation at the acyl-CoA-binding domain to cytosolic ACBPs but is distinct by the presence of an N-terminal transmembrane domain and C-terminal ankyrin repeats. The function of the acyl-CoA-binding domain in ACBP2 has ...
Nicotiana tabacum; cultivars; tobacco; leaves; plant extracts; leaf oils; chemical composition; chemical analysis; quantitative analysis; ethers; esters; supercritical fluid extraction; carbon dioxide; nicotine; volatile organic compounds; aromatic hydrocarbons; alkanes; Serbia
Abstract:
... A study of the chemical composition of ether and ethyl acetate extracts of the Serbian selected tobacco types Yaka, Prilep and Otlja was performed using GC and GC/MS. The major constituents were: nicotine (24.2-58.9% of the total material detected in the ethyl acetate extracts and 46.1-49.5% of ether extracts), neophytadiene (4.0-17.9% of ethyl acetate extracts and 11.2-31.9% of ether extracts) an ...
... Arabidopsis thaliana GAMT1 and GAMT2 encode enzymes that catalyze formation of the methyl esters of gibberellins (GAs). Ectopic expression of GAMT1 or GAMT2 in Arabidopsis, tobacco (Nicotiana tabacum), and petunia (Petunia hybrida) resulted in plants with GA deficiency and typical GA deficiency phenotypes, such as dwarfism and reduced fertility. GAMT1 and GAMT2 are both expressed mainly in whole s ...
... Previous experiments with tobacco (Nicotiana tabacum L. cv Samsun NN) plants revealed that jasmonic acid methyl ester (JAME) induces the expression of a cytoplasmic/nuclear lectin in leaf cells and provided the first evidence that jasmonates affect the expression of carbohydrate-binding proteins in plant cells. To corroborate the induced accumulation of relatively large amounts of a cytoplasmic/nu ...
... Although phytosterols in tobacco leaves have specific effects on tobacco quality, there is little research on the distribution of free and conjugated phytosterols in various tobacco leaves. In this paper, we explored the content and composition of phytosterols in representative cured tobacco leaves by gas chromatography of TMS-ether derivatives. We found that phytosterol contents in tobacco leaves ...
... C₂H₄ is associated with plant defense, but its role during the hypersensitive response (HR) remains largely uncharacterized. C₂H₄ production in tobacco (Nicotiana tabacum) following inoculation with HR-eliciting Pseudomonas syringae pathovars measured by laser photoacoustic detection was biphasic. A first transient rise (C₂H₄-I) occurred 1 to 4 h following inoculation with HR-eliciting, disease-fo ...
... The leaf trichome of tobacco (Nicotiana tabacum) represents a unique secretory structure in which the basal trichome cell is connected to the epidermis by numerous plasmodesmata (PD). Small fluorescent probes microinjected into the basal trichome cell moved apically into distal trichome cells but not into the subtending epidermal cell. In marked contrast, the same probes moved apically into tricho ...
... A huge amount of kernel cake, which contains a variety of toxins including phorbol esters (tumor promoters), is projected to be generated yearly in the near future by the Jatropha biodiesel industry. We showed that the kernel cake strongly inhibited plant seed germination and root growth and was highly toxic to carp fingerlings, even though phorbol esters were undetectable by HPLC. Therefore it mu ...