374 research outputs found
Fatty Acids and their Derivatives as Renewable Platform Molecules for the Chemical Industry
Oils and fats of vegetable and animal origin remain an important renewable feedstock for the chemical industry. Their industrial use has increased during the last 10 years from 31 to 51 million tonnes annually. Remarkable achievements made in the field of oleochemistry in this timeframe are summarized herein, including the reduction of fatty esters to ethers, the selective oxidation and oxidative cleavage of C–C double bonds, the synthesis of alkyl-branched fatty compounds, the isomerizing hydroformylation and alkoxycarboxylation, and olefin metathesis. The use of oleochemicals for the synthesis of a great variety of polymeric materials has increased tremendously, too. In addition to lipases and phospholipases, other enzymes have found their way into biocatalytic oleochemistry. Important achievements have also generated new oil qualities in existing crop plants or by using microorganisms optimized by metabolic engineering
Lipid mediators from pollen act as chemoattractants and activators of polymorphonuclear granulocytes
Lolium perenne apoplast metabolomics for identification of novel metabolites produced by the symbiotic fungus Epichlo festucae
Epichloe festucae is an endophytic fungus that forms a symbiotic association with Lolium perenne. Here we analysed how the metabolome of the ryegrass apoplast changed upon infection of this host with sexual and asexual isolates of E. festucae. A metabolite fingerprinting approach was used to analyse the metabolite composition of apoplastic wash fluid from uninfected and infected L. perenne. Metabolites enriched or depleted in one or both of these treatments were identified using a set of interactive tools. A genetic approach in combination with tandem MS was used to identify a novel product of a secondary metabolite gene cluster. Metabolites likely to be present in the apoplast were identified using MarVis in combination with the BioCyc and KEGG databases, and an in‐house Epichloe metabolite database. We were able to identify the known endophyte‐specific metabolites, peramine and epichloecyclins, as well as a large number of unknown markers. To determine whether these methods can be applied to the identification of novel Epichloe‐derived metabolites, we deleted a gene encoding a NRPS (lgsA) that is highly expressed in planta. Comparative MS analysis of apoplastic wash fluid from wild‐type‐ vs mutant‐infected plants identified a novel Leu/Ile glycoside metabolite present in the former.This research was supported by a grant from the Tertiary Education Commission to the Bio-Protection Research Centre and by Massey University. BS was supported by an Alexander von Humboldt Research Award. IF was supported by the Deutsche Forschungsgemeinschaft (ZUK 45/2010)
Determination of Total Homocysteine in Human Plasma by Isocratic High-Performance Liquid Chromatography
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Metabolite-based clustering and visualization of mass spectrometry data using one-dimensional self-organizing maps
Update on LIPID MAPS classification, nomenclature, and shorthand notation for MS-derived lipid structures
A comprehensive and standardized system to report lipid structures analyzed by mass spectrometry is essentialfor the communication and storage of lipidomics data. Herein, an update on both the LIPID MAPSclassification system and shorthand notation of lipid structures is presented for lipid categories Fatty Acyls(FA), Glycerolipids (GL), Glycerophospholipids (GP), Sphingolipids (SP), and Sterols (ST). With its majorchanges, i.e. annotation of ring double bond equivalents and number of oxygens, the updated shorthandnotation facilitates reporting of newly delineated oxygenated lipid species as well. For standardized reportingin lipidomics, the hierarchical architecture of shorthand notation reflects the diverse structural resolutionpowers provided by mass spectrometric assays. Moreover, shorthand notation is expanded beyond mammalianphyla to lipids from plant and yeast phyla. Finally, annotation of atoms is included for the use of stableisotope-labelled compounds in metabolic labelling experiments or as internal standards
Arabidopsis CPR5 Independently Regulates Seed Germination and Postgermination Arrest of Development through LOX Pathway and ABA Signaling
The phytohormone abscisic acid (ABA) and the lipoxygenases (LOXs) pathway play important roles in seed germination and seedling growth and development. Here, we reported on the functional characterization of Arabidopsis CPR5 in the ABA signaling and LOX pathways. The cpr5 mutant was hypersensitive to ABA in the seed germination, cotyledon greening and root growth, whereas transgenic plants overexpressing CPR5 were insensitive. Genetic analysis demonstrated that CPR5 gene may be located downstream of the ABI1 in the ABA signaling pathway. However, the cpr5 mutant showed an ABA independent drought-resistant phenotype. It was also found that the cpr5 mutant was hypersensitive to NDGA and NDGA treatment aggravated the ABA-induced delay in the seed germination and cotyledon greening. Taken together, these results suggest that the CPR5 plays a regulatory role in the regulation of seed germination and early seedling growth through ABA and LOX pathways independently
An organizational framework and strategic implementation for system-level change to enhance research-based practice: QUERI Series
<p>Abstract</p> <p>Background</p> <p>The continuing gap between available evidence and current practice in health care reinforces the need for more effective solutions, in particular related to organizational context. Considerable advances have been made within the U.S. Veterans Health Administration (VA) in systematically implementing evidence into practice. These advances have been achieved through a system-level program focused on collaboration and partnerships among policy makers, clinicians, and researchers.</p> <p>The Quality Enhancement Research Initiative (QUERI) was created to generate research-driven initiatives that directly enhance health care quality within the VA and, simultaneously, contribute to the field of implementation science. This paradigm-shifting effort provided a natural laboratory for exploring organizational change processes. This article describes the underlying change framework and implementation strategy used to operationalize QUERI.</p> <p>Strategic approach to organizational change</p> <p>QUERI used an evidence-based organizational framework focused on three contextual elements: 1) cultural norms and values, in this case related to the role of health services researchers in evidence-based quality improvement; 2) capacity, in this case among researchers and key partners to engage in implementation research; 3) and supportive infrastructures to reinforce expectations for change and to sustain new behaviors as part of the norm. As part of a QUERI Series in <it>Implementation Science</it>, this article describes the framework's application in an innovative integration of health services research, policy, and clinical care delivery.</p> <p>Conclusion</p> <p>QUERI's experience and success provide a case study in organizational change. It demonstrates that progress requires a strategic, systems-based effort. QUERI's evidence-based initiative involved a deliberate cultural shift, requiring ongoing commitment in multiple forms and at multiple levels. VA's commitment to QUERI came in the form of visionary leadership, targeted allocation of resources, infrastructure refinements, innovative peer review and study methods, and direct involvement of key stakeholders. Stakeholders included both those providing and managing clinical care, as well as those producing relevant evidence within the health care system. The organizational framework and related implementation interventions used to achieve contextual change resulted in engaged investigators and enhanced uptake of research knowledge. QUERI's approach and progress provide working hypotheses for others pursuing similar system-wide efforts to routinely achieve evidence-based care.</p
Molecular characterization of lipoxygenase genes and their expression analysis against biotic and abiotic stresses in Panax ginseng
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