Search Results
Results 651 - 700 of 1380
< 9 10 11 12 13 14 15 16 17 18 19 >
Eberle David - - 2009
The final reactions of rosmarinic acid biosynthesis, the introduction of the aromatic 3- and 3'-hydroxyl groups, are catalysed by cytochrome P450-dependent hydroxylases. The cDNAs encoding CYP98A14 as well as a NADPH:cytochrome P450 reductase (CPR) were isolated from Coleus blumei and actively expressed in Saccharomyces cerevisiae. The CYP98A14-cDNA showed an open ...
Singh Shailendra P - - 2008
The mycosporine-like amino acid (MAA) profile of a rice-field cyanobacterium, Anabaena doliolum, was studied under PAR and PAR + UVR conditions. The high-performance liquid chromatographic analysis of water-soluble compounds reveals the biosynthesis of three MAAs, mycosporine-glycine (lambda (max) = 310 nm), porphyra-334 (lambda (max) = 334 nm) and shinorine (lambda ...
Kanellakopoulou K - - 2008
The characteristics of cancellous bone allografts as carriers of fusidic acid and teicoplanin are described. Particles of cancellous bone were compressed into a wiremesh cylinder; five replicas were impregnated for one hour into fusidic acid; and another five for one hour into teicoplanin. Elution was estimated daily. Concentrations of fusidic ...
Kuwano Mio - - 2009
Phytic acid acts as the major storage form of phosphorus in plant seeds and is poorly digested by monogastric animals. The degradation of phytic acid in animal diets is necessary to overcome both environmental and nutritional issues. The enzyme 1D-myo-inositol 3-phosphate [Ins(3)P(1)] synthase (EC 5.5.1.4) catalyses the first step of ...
Panagopoulos Periklis - - 2008
Stimulan was evaluated in vitro as a biodegradable carrier for local delivery of moxifloxacin and fusidic acid. Moxifloxacin or fusidic acid was mixed with calcium sulphate at a ratio of 95:5 to prepare five replicas per antibiotic. In vitro elution was estimated daily using a high-performance liquid chromatography (HPLC) system. ...
Delgado Alejandro - - 2008
Fusidic acid interferes with the release of elongation factor G (EF-G) after the translocation step of protein synthesis. The objective of this study was to characterize the fusidic acid stimulon of a fusidic acid-susceptible strain of Staphylococcus aureus (SH1000). S. aureus microarrays and real-time PCR determined transcriptome alterations occurring in ...
Eliot Andrew C - - 2008
The antibiotics fosmidomycin and FR900098 are members of a unique class of phosphonic acid natural products that inhibit the nonmevalonate pathway for isoprenoid biosynthesis. Both are potent antibacterial and antimalarial compounds, but despite their efficacy, little is known regarding their biosynthesis. Here we report the identification of the Streptomyces rubellomurinus ...
Shen C R - - 2008
Production of higher alcohols via the keto-acid intermediates found in microorganism's native amino-acid pathways has recently shown promising results. In this work, an Escherichia coli strain that produces 1-butanol and 1-propanol from glucose was constructed. The strain first converts glucose to 2-ketobutyrate, a common keto-acid intermediate for isoleucine biosynthesis. Then, ...
Bumpus Stefanie B - - 2008
Polyketide biosynthesis is typically directed by cis-acting catalytic domains. In the case of the Bacillus subtilis secondary metabolite dihydrobacillaene, the cis-acting domains are not sufficient to generate the saturated C14'-C15' bond. In this communication, we identify PksE as a trans-acting enoyl reductase utilized in the biosynthesis of this portion of ...
Braun Sascha D - - 2008
The epiphyte Pseudomonas syringae pv. syringae 22d/93 (Pss22d) produces a toxin that strongly inhibits the growth of its relative, the plant pathogen P. syringae pv. glycinea. The inhibition can be overcome by supplementing the growth medium with the essential amino acid, L-arginine; this suggests that the toxin acts as an ...
Mu Jinye - - 2008
In plants, fatty acids are de novo synthesized predominantly in plastids from acetyl-coenzyme A. Although fatty acid biosynthesis has been biochemically well studied, little is known about the regulatory mechanisms of the pathway. Here, we show that overexpression of the Arabidopsis (Arabidopsis thaliana) LEAFY COTYLEDON1 (LEC1) gene causes globally increased ...
Bhinu V-S - - 2009
Arabidopsis thaliana and other members of the Brassicaceae accumulate the hydroxycinnamic acid esters sinapoylmalate in leaves and sinapoylcholine in seeds. Our recent understanding of the phenylpropanoid pathway although complex has enabled us to perturb the sinapine biosynthesis pathway in plants. Sinapine (sinapoylcholine) is the most abundant antinutritional phenolic compound in ...
Cutignano Adele - - 2008
The biosynthesis of lignarenones 1 and 2, the major polyketides of the Mediterranean mollusc Scaphander lignarius is described. The process is primed by benzoic acid and requires acetate and propionate as extender units. The labeling pattern suggests PKS-like synthesis of an unusual E,Z,E-triene chain and origin of the benzoate unit ...
O'Mahony C - - 2008
Rhabdomyolysis is a rare but life-threatening complication of statin therapy. A 74-year-old man, treated with atorvastatin, developed rhabdomyolysis after the co-administration of fusidic acid and flucloxacillin. The patient recovered with supportive treatment and subsequently tolerated reintroduction of atorvastatin. Pharmacokinetic interactions can cause raised plasma statin concentrations, which can precipitate rhabdomyolysis ...
Uhlig Silvio - - 2008
Four major alkaloids in the extracts from sclerotia of Claviceps purpurea, picked from wild grasses, have been identified as lactam (non-cyclol) ergot alkaloids. The structural information was obtained from ion trap MS and NMR spectroscopy. The data for one of the lactam ergot alkaloids were coinciding with ergocristam [N-(lysergyl-valyl)-cyclo(phenylalanyl-prolyl)]. The ...
Geelen Math J H - - 2008
The cellular ATP concentration was tested for its effect on fatty acid biosynthesis from glucose in hepatocytes. ATP was manipulated by adding increasing concentrations of cycloheximide, amytal, atractyloside, 2,4-dinitrophenol or adenosine. A slight decrease in cellular ATP coincided with a stimulation of fatty acid biosynthesis whereas a further lowering of ...
Tipparaju Suresh K - - 2008
Enoyl-ACP reductase (ENR), the product of the FabI gene, from Bacillus anthracis (BaENR) is responsible for catalyzing the final step of bacterial fatty acid biosynthesis. A number of novel 2-pyridone derivatives were synthesized and shown to be potent inhibitors of BaENR.
Munné-Bosch Sergi - - 2009
The goal of the present research was to obtain new insights into the mechanisms underlying drought stress resistance in plants. Specifically, we evaluated changes in the expression of genes encoding enzymes involved in isoprenoid biosynthesis, together with the levels of the corresponding metabolites (chlorophylls, carotenoids, tocopherols and abscisic acid), in ...
Zhou Hui - - 2008
Resorcylic acid lactones represent a unique class of fungal polyketides and display a wide range of biological activities, such as nanomolar inhibitors of Hsp90 and MAP kinase. The biosynthesis of these compounds is proposed to involve two fungal polyketide synthases (PKS) that function collaboratively to yield a 14-membered macrolactone with ...
Pankewitz Florian - - 2008
Polyketides are known to be used by insects for pheromone communication and defence against enemies. Although in microorganisms (fungi, bacteria) and plants polyketide biogenesis is known to be catalysed by polyketide synthases (PKS), no insect PKS involved in biosynthesis of pheromones or defensive compounds have yet been found. Polyketides detected ...
Sheoran Anita - - 2008
Thiocoraline is a thiodepsipeptide antitumor agent that belongs to the family of bisintercalator natural products that bind duplex DNA through their two planar intercalating moieties. In thiocoraline, the 3-hydroxyquinaldic acid (3HQA) chromophores required for intercalation are derived from L-Trp. We have expressed the Micromonospora sp. ML1 tryptophan 2,3-dioxygenase(TDO) TioF, purified ...
Palme Klaus - - 2008
There is much interest in understanding the pathways that trigger biosynthesis of the plant hormone auxin. In this issue, Stepanova et al. (2008) and Tao et al. (2008) reveal that a small family of tryptophan aminotransferases catalyze formation of indole-3-pyruvic acid (IPA) from L-tryptophan (L-Trp), the first step in a ...
Schaller Florian - - 2008
Jasmonates are derived from oxygenated fatty acids (oxylipins) via the octadecanoid pathway and are characterized by a pentacyclic ring structure. They have regulatory functions as signaling molecules in plant development and adaptation to environmental stress. Recently, we solved the structure of allene oxide cyclase 2 (AOC2) of Arabidopsis thaliana, which ...
Luo Yinggang - - 2008
Neocarzinostatin, a clinical anticancer drug, is the archetypal member of the chromoprotein family of enediyne antitumor antibiotics that are composed of a nonprotein chromophore and an apoprotein. The neocarzinostatin chromophore consists of a nine-membered enediyne core, a deoxyaminosugar, and a naphthoic acid moiety. We have previously cloned and sequenced the ...
Wang Wenya - - 2009
Catalyzed by phenylalanine ammonia-lyase from Rhodotorula glutinis, 2% trans-cinnamic acid and 0.5 mol/l (15NH4)2SO4 was bioconverted to 15NL-phenylalanine. The yield and the purity of 15NL-phenylalanine reached 71 and 99.3%, respectively. The results showed that 96% of 15N was labeled on the L-phenylalanine and 88% of (15NH4)2SO4 was recovered. The present ...
Simirgiotis Mario J - - 2008
Bioassay-guided fractionation of the methanolic extracts of the pulp and seeds of the fruits of Syzygium samarangense Merr. & Perry (Blume) led to the identification of four cytotoxic compounds and eight antioxidants on the basis of HPLC-PDA analysis, MS, and various NMR spectroscopic techniques. Three C-methylated chalcones, 2',4'-dihydroxy-3',5'-dimethyl-6'-methoxychalcone (1), 2',4'-dihydroxy-3'-methyl-6'-methoxychalcone ...
Luttik M A H - - 2008
A quantitative analysis of the impact of feedback inhibition on aromatic amino acid biosynthesis was performed in chemostat cultures of Saccharomyces cerevisiae. Introduction of a tyrosine-insensitive allele of ARO4 (encoding 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase) caused a three-fold increase of intracellular phenylalanine and tyrosine concentrations. These amino acids were not detected extracellularly. However, ...
Tsfadia Oren - - 2008
We combine the use of labeled precursors with enzyme inhibitors to decipher the biosynthetic pathway of pheromone biosynthesis and the rate-limiting step/s that are regulated by pheromone biosynthesis activating neuropeptide (PBAN). We demonstrate that Plodia interpunctella is able to utilize hexadecanoic acid, and to a lesser extent tetradecanoic acid, for ...
Xia Guoqing - - 2008
Wall teichoic acid (WTA) contributes profoundly to the virulence of Staphylococcus aureus. The successful in vitro reconstitution of poly-ribitolphosphate WTA biosynthesis using recombinant enzymes sheds new light on WTA enzymology and paves the way for developing new antibiotics that target WTA biosynthesis, as discussed in Brown et al. in a ...
Humljan J - - 2008
UDP-N-acetylmuramic acid (UDP-MurNAc) is a substrate of MurC, an important enzyme in the intracellular pathway of bacterial peptidoglycan biosynthesis. Various approaches towards preparation of UDP-MurNAc have been published but these synthetic preparations were shown to include many problematic steps. An optimization study with the focus on muramyl phosphate and UMP-morpholidate ...
Mirza Sajjad Hussain - - 2008
OBJECTIVE: To find out the frequency of low-level quinolone-resistance in Multi-Drug Resistant (MDR) typhoid using nalidixic acid screening disc. STUDY DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: Armed Forces Institute of Pathology, Rawalpindi, from January 2005 to December 2005. MATERIALS AND METHODS: Blood was obtained from suspected cases of ...
Kaliszewski PaweĊ‚ - - 2008
Rsp5 is a conserved ubiquitin ligase involved in regulation of numerous cellular processes. A growing number of publications describing new functions of the ligase have appeared in recent years. Rsp5 was shown to be involved in the control of intracellular trafficking of proteins via endocytosis and multivesicular body sorting. Moreover, ...
Heckmann Lars-Henrik - - 2008
Eicosanoids are biologically active, oxygenated metabolites of three C20 polyunsaturated fatty acids. They act as signalling molecules within the autocrine or paracrine system in both vertebrates and invertebrates mainly functioning as important mediators in reproduction, the immune system and ion transport. The biosynthesis of eicosanoids has been intensively studied in ...
Goodman C D - - 2008
Fatty acid biosynthesis pathways in protozoan parasites are reviewed with a view to targeting this metabolism for drug therapy. The type II fatty acid biosynthesis pathways derived from bacteria in protozoan relict plastids and mitochondria are examined in different groups with emphasis on apicomplexa. The suitability of different enzymes from ...
Yurlova N A - - 2008
Dothideaceous black yeast-like fungi (BYF) are known to synthesise DHN-melanin that is inhibited by the systemic fungicide tricyclazole. The final step of the DHN melanin pathway is the conjoining of 1,8-DHN molecules to form the melanin polymer. There are several candidate enzymes for this step, including phenoloxidases such as tyrosinase ...
Liénard Marjorie A - - 2008
Moths have evolved highly successful mating systems, relying on species-specific mixtures of sex pheromone components for long-distance mate communication. Acyl-CoA desaturases are key enzymes in the biosynthesis of these compounds and to a large extent they account for the great diversity of pheromone structures in Lepidoptera. A novel desaturase gene ...
Gratraud Paul P Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier II et I, CNRS, UMR 5235, case 107, Place Eugène Bataillon, 34095 Montpellier Cedex 05, - - 2008
The antimalarial agents NAS-91 and NAS-21 were found to express potent antimycobacterial activity, NAS-91 being more active than NAS-21. They partially inhibited mycolic acid biosynthesis and profoundly altered oleic acid production. The development of a cell-free assay for Delta 9-desaturase activity allowed direct demonstration of the inhibition of oleic acid ...
Godio Ramiro P - - 2007
The basidiomycete Hypholoma sublateritium produces the triterpenoid antitumor clavaric acid, an inhibitor of the human Ras-farnesyl transferase. The H. sublateritium squalene epoxidase gene (erg1) has been cloned and shown to encode a flavoprotein monooxygenase that requires FAD, NADPH, and P450 cofactors. Silencing of the erg1 gene in H. sublateritium using ...
Arruda Denise Costa - - 2008
The isoprenoid metabolic pathway in protozoa of the Leishmania genus exhibits distinctive characteristics. These parasites, as well as other members of the Trypanosomatidae family, synthesize ergosterol, instead of cholesterol, as the main membrane sterol lipid. Leishmania has been shown to utilize leucine, instead of acetate as the main precursor for ...
Ohashi Yoshiaki - - 2008
Metabolic changes in response to histidine starvation were observed in histidine-auxotrophic Escherichia coli using a capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS)-based metabolomics technique. Prior to the analysis, we prepared an E. coli metabolome list of 727 metabolites reported in the literature. An improved method for metabolite extraction was developed, which ...
Abad José-Luis - - 2007
The stereochemical course of the Delta13 desaturation involved in the biosynthesis of Thaumetopoea pityocampa sex pheromone was studied using stereotopically labeled and tagged palmitic acids as metabolic probes. In the synthetic pathway, a functionalized acetylene common synthon was used for introducing the four deuterium tags. Further coupling of the tetradeuterated ...
AbouZid Sameh - - 2007
Thiophene A and thiophene A diol are the major polyacetylenes isolated from the hairy roots of Ambrosia maritima (Asteraceae) cultured under continuous light irradiation. The biosynthesis of thiophene A was studied using [1-(13)C]-, [2-(13)C]-, [1,2-(13)C]-acetates. The biosynthesis of thiarubrine A, produced by hairy roots cultured in the dark, was studied ...
Garscha Ulrike - - 2007
Aspergillus sp. contain ppoA, ppoB, and ppoC genes, which code for fatty acid oxygenases with homology to fungal linoleate 7,8-diol synthases (7,8-LDS) and cyclooxygenases. Our objective was to identify these enzymes, as ppo gene replacements show critical developmental aberrancies in sporulation and pathogenicity in the human pathogen Aspergillus fumigatus and ...
Teichmann Beate - - 2007
The phytopathogenic basidiomycetous fungus Ustilago maydis secretes large amounts of the glycolipid biosurfactant ustilagic acid (UA). UA consists of 15,16-dihydroxypalmitic or 2,15,16-trihydroxypalmitic acid, which is O-glycosidically linked to cellobiose at its terminal hydroxyl group. In addition, the cellobiose moiety is acetylated and acylated with a short-chain hydroxy fatty acid. We ...
Schneider Kathrin - - 2007
In the genome of Bacillus amyloliquefaciens FZB42, three operons pks1, pks2, and pks3 were identified which encode the biosynthesis of polyketides. pks1 and pks3 have been attributed to the production of bacillaene and difficidin/oxydifficidin, respectively, while the pks2 product remained hitherto unknown. Mass spectrometric analysis of the culture filtrates of ...
Morar Mariya - - 2007
Genes responsible for the generation of 3-dehydroquinate (DHQ), an early metabolite in the established shikimic pathway of aromatic amino acid biosynthesis, are absent in most euryarchaeotes. Alternative gene products, Mj0400 and Mj1249, have been identified in Methanocaldococcus jannaschii as the enzymes involved in the synthesis of DHQ. 2-Amino-3,7-dideoxy-d-threo-hept-6-ulosonic acid (ADH) ...
Wright H Tonie - - 2007
The fatty acid biosynthesis pathway is an attractive but still largely unexploited target for the development of new antibacterial agents. The extended use of the antituberculosis drug isoniazid and the antiseptic triclosan, which are inhibitors of fatty acid biosynthesis, validates this pathway as a target for antibacterial development. Differences in ...
Nasution Uly - - 2008
The relation between central metabolism and the penicillin biosynthesis pathway in Penicillium chrysogenum was studied by manipulating the steady-state flux in both pathways. A high producing industrial strain was cultivated at a growth rate mu=0.05 h(-1) in glucose-limited chemostat cultures, both under penicillin-G producing and non-producing conditions. Non-producing conditions were ...
Goller Stephan - - 2007
The hydrocarbons (3Z,6Z,9Z)-3,6,9-octadecatriene (3Z,6Z,9Z-18:H) and (3Z,6Z,9Z)-3,6,9-nonadecatriene (3Z,6Z,9Z-19:H) constitute the pheromone of the winter moth, Erannis bajaria. These compounds belong to a large group of lepidopteran pheromones which consist of unsaturated hydrocarbons and their corresponding oxygenated derivatives. The biosynthesis of such hydrocarbons with an odd number of carbons in the chain ...
Lopes Adriana A - - 2007
The biosynthesis of (2S)-2-methyl-2-(4'-methyl-3'-pentenyl)-8-(3''-methyl-2-butenyl)-2H-1-benzopyran-6-carboxylic acid (gaudichaudianic acid), the major metabolite in leaves and roots of Piper gaudichaudianum Kunth (Piperaceae), has been investigated employing [1-(13)C]-D-glucose as precursor. The labelling pattern in the isolated gaudichaudianic acid was determined by quantitative (13)C NMR spectroscopy analysis and was consistent with involvement of both mevalonic ...
< 9 10 11 12 13 14 15 16 17 18 19 >