Plantmetabolomics.org: mass spectrometry-based Arabidopsis metabolomics—database and tools update

The PlantMetabolomics (PM) database (http://www.plantmetabolomics.org) contains comprehensive targeted and untargeted mass spectrum metabolomics data for Arabidopsis mutants across a variety of metabolomics platforms. The database allows users to generate hypotheses about the changes in metabolism for mutants with genes of unknown function. Version 2.0 of PlantMetabolomics.org currently contains data for 140 mutant lines along with the morphological data. A web-based data analysis wizard allows researchers to select preprocessing and data-mining procedures to discover differences between mutants. This community resource enables researchers to formulate models of the metabolic network of Arabidopsis and enhances the research community's ability to formulate testable hypotheses concerning gene functions. PM features new web-based tools for data-mining analysis, visualization tools and enhanced cross links to other databases. The database is publicly available. PM aims to provide a hypothesis building platform for the researchers interested in any of the mutant lines or metabolites

Policiklički aromatski ugljikovodici u zraku okolice plinskog polja Molve

Small-volume air samples (~7 m3 per 24 h) of airborne PM10 particle fraction were collected on quartz fibre filters at two measuring sites in the vicinity of the gas field Molve in April and July 2006. It took five to seven days for each sample to collect and one month to collect five to seven samples. Mass concentrations of PM10 fractions were determined by gravimetry while PAHs were analysed using a HPLC with a fluorescent detector. The analysis included fluoranthene (Flu), pyrene (Pyr), benzo(a)anthracene (BaA), chrysene (Cry), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), benzo(ghi)perylene (BghiP) and indene(1,2,3-cd)pyrene (Ind). Average concentrations of all PAHs in April at site A were slightly higher than at site B while in July they were lower and similar on both sites. Average BaP concentration measured at site A in April was 0.156 ng m-3 and at site B 0.129 ng m-3, while July BaP averages were 0.022 ng m-3 at both sites. In both months, the mass concentration of BaP was lower than the limit value (1 ng m-3) and well below the tolerant value (2 ng m-3) set by a Croatian regulation of 2005. This suggests that the air near gas field Molve was of acceptable quality in respect to BaP at the time of the measurement.Uzorci PM10 frakcije lebdećih čestica skupljani su prosisavanjem malog volumena zraka (~7 m3 za 24 h) kroz filtre od kvarcnih vlakana. Svaki je uzorak skupljan tijekom pet do sedam dana na dva mjerna mjesta u okolici plinskog polja Molve. Uzorkovanje je provedeno tijekom travnja i srpnja 2006. godine. Masene koncentracije PM10 frakcije određene su gravimetrijski, dok je analiza policikličkih aromatskih ugljikovodika (PAU) rađena tekućinskom kromatografijom visoke djelotvornosti (HPLC) s fluorescentnim detektorom. Mjereni su sljedeći PAU: fluoranten, piren, benzo(a)antracen, krizen, benzo(b)fluoranten, benzo(k)fluoranten, benzo(a)piren, benzo(ghi)perilen i indeno(1,2,3-cd)piren. Srednje vrijednosti masenih koncentracija svih PAU u travnju na mjernome mjestu A bile su neznatno više od onih na mjernome mjestu B, dok su u srpnju na oba mjerna mjesta bile vrlo slične. Srednja vrijednost koncentracije BaP izmjerenog u travnju na mjernome mjestu A bila je viša od vrijednosti izmjerene na mjernome mjestu B. U srpnju su srednje vrijednosti bile znatno niže i na oba mjerna mjesta iznosile su 0.022 ng m-3. Iz rezultata dobivenih mjerenjem vidljivo je da je koncentracija benzo(a)pirena bila znatno niža od granične vrijednosti (1 ng m-3) i tolerantne vrijednosti (1 ng m-3, Uredba iz 2005.), pa možemo zaključiti da je zrak u okolici plinskog polja Molve tijekom istraživanog razdoblja bio prve kategorije kakvoće

Current status of the multinational Arabidopsis community

The multinational Arabidopsis research community is highly collaborative and over the past thirty years these activities have been documented by the Multinational Arabidopsis Steering Committee (MASC). Here, we (a) highlight recent research advances made with the reference plant Arabidopsis thaliana; (b) provide summaries from recent reports submitted by MASC subcommittees, projects and resources associated with MASC and from MASC country representatives; and (c) initiate a call for ideas and foci for the “fourth decadal roadmap,” which will advise and coordinate the global activities of the Arabidopsis research community

Mechanistic Insights into Ring-Opening and Decarboxylation of 2-Pyrones in Liquid Water and Tetrahydrofuran

2-Pyrones, such as triacetic acid lactone, are a promising class of biorenewable platform chemicals that provide access to an array of chemical products and intermediates. We illustrate through the combination of results from experimental studies and first-principle density functional theory calculations that key structural features dictate the mechanisms underlying ring-opening and decarboxylation of 2-pyrones, including the degree of ring saturation, the presence of C═C bonds at the C4═C5 or C5═C6 positions within the ring, as well as the presence of a β-keto group at the C4 position. Our results demonstrate that 2-pyrones undergo a range of reactions unique to their structure, such as retro-Diels–Alder reactions and nucleophilic addition of water. In addition, the reactivity of 2-pyrones and the final products formed is shown to depend on the solvent used and the acidity of the reaction environment. The mechanistic insights obtained here provide guidance for the selective conversion of 2-pyrones to targeted chemicals.Reprinted (adapted) with permission from Journal of American Chemical Society, 135(15); 5699-5708. Doi: 10.1021/ja312075r. Copyright 2013 American Chemical Society. </p