Learn More
[1] Atmospheric levoglucosan has been determined as a proxy for ‘‘biomass smoke’’ in samples from six background stations on a west–east transect extending from the Atlantic (Azores) to the mid-European background site KPZ (K-Puszta, Hungary). Concentration levels of levoglucosan (biannual averages) in the west–east transect range from 0.005 mg/m at the(More)
[1] On the basis of a 2-year comprehensive data set obtained within the CARBOSOL project, seasonal source apportionment of PM2.5 aerosol is attempted for five rural/remote sites in Europe. The approach developed combines radiocarbon measurements with bulk measurements of organic carbon (OC), elemental carbon (EC), and two organic tracers (levoglucosan and(More)
In Arabidopsis thaliana, silencing of hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase (HCT), a lignin biosynthetic gene, results in a strong reduction of plant growth. We show that, in HCT-silenced plants, lignin synthesis repression leads to the redirection of the metabolic flux into flavonoids through chalcone synthase activity.(More)
The hydroxyl group in the 3-position of the phenylpropanoid compounds is introduced at the level of coumarate shikimate/quinate esters, whose synthesis implicates an acyltransferase activity. Specific antibodies raised against the recombinant tobacco (Nicotiana tabacum) acyltransferase revealed the accumulation of the enzyme in stem vascular tissues of(More)
A protein hydrolyzing hydroxycinnamoyl-CoA esters has been purified from tobacco stem extracts by a series of high pressure liquid chromatography steps. The determination of its N-terminal amino acid sequence allowed design of primers permitting the corresponding cDNA to be cloned by PCR. Sequence analysis revealed that the tobacco gene belongs to a plant(More)
Four endochitinases (poly[1,4-(N-acetyl-beta-D-glucosaminide)] glycanohydrolase, EC 3.2.1.14) have been purified from leaves of Nicotiana tabacum cv. Samsun NN reacting hypersensitively to tobacco mosaic virus. Two of them are acidic proteins of molecular weights 27,500 and 28,500 and have been identified as 2 of the 10 pathogenesis-related proteins that(More)
Three of the ten acidic ;pathogenesis-related' (PR) proteins known to accumulate in Nicotiana tabacum cv Samsun NN reacting hypersensitively to tobacco mosaic virus, namely -O, -N and -2, have been shown to have 1,3-beta-glucanase (EC 3.2.1.39) activity. By using sera raised against each protein purified to homogeneity close serological relationships have(More)
The precise structure of the sporopollenin polymer that is the major constituent of exine, the outer pollen wall, remains poorly understood. Recently, characterization of Arabidopsis thaliana genes and corresponding enzymes involved in exine formation has demonstrated the role of fatty acid derivatives as precursors of sporopollenin building units. Fatty(More)
A proteinase inhibitor is strongly induced in tobacco leaves reacting hypersensitively to tobacco mosaic virus. The tobacco inhibitor is highly active against four different serine endoproteinases of fungal and bacterial origin (EC 3.4.21.14) but inhibits poorly two serine endoproteinases of animal origin, trypsin (EC 3.4.21.4) and chymotrypsin (EC(More)
BACKGROUND Most reports concerning the outcome of patients with biliary tract injury during laparoscopic cholecystectomy come from tertiary referral centers, and results could be very different in the everyday practice of community surgeons. OBJECTIVE The objective is to define the presentation, mechanisms, results of treatment, and long-term outcome of(More)