Institute of Analytical Chemistry
Institute of Analytical Chemistry
Omann M.R.,Vienna University of Technology |
Lehner S.,Institute of Analytical Chemistry |
Rodriguez C.E.,Vienna University of Technology |
Brunner K.,Vienna University of Technology |
And 2 more authors.
Microbiology | Year: 2012
Mycoparasitic Trichoderma species are applied as biocontrol agents in agriculture to guard plants against fungal diseases. During mycoparasitism, Trichoderma directly interacts with phytopathogenic fungi, preceded by a specific recognition of the host and resulting in its disarming and killing. In various fungal pathogens, including mycoparasites, signalling via heterotrimeric G proteins plays a major role in regulating pathogenicity-related functions. However, the corresponding receptors involved in the recognition of host-derived signals are largely unknown. Functional characterization of Trichoderma atroviride Gpr1 revealed a prominent role of this seven-transmembrane protein of the cAMP-receptor-like family of fungal G-proteincoupled receptors in the antagonistic interaction with the host fungus and governing of mycoparasitism-related processes. Silencing of gpr1 led to an avirulent phenotype accompanied by an inability to attach to host hyphae. Furthermore, gpr1-silenced transformants were unable to respond to the presence of living host fungi with the expression of chitinase- and proteaseencoding genes. Addition of exogenous cAMP was able to restore host attachment in gpr1- silenced transformants but could not restore mycoparasitic overgrowth. A search for downstream targets of the signalling pathway(s) involving Gpr1 resulted in the isolation of genes encoding e.g. a member of the cyclin-like superfamily and a small secreted cysteine-rich protein. Although silencing of gpr1 caused defects similar to those of mutants lacking the Tga3 Ga protein, no direct interaction between Gpr1 and Tga3 was observed in a split-ubiquitin two-hybrid assay. © 2012 SGM.
Qian X.,Institute of Analytical Chemistry |
Zhang Q.,Institute of Analytical Chemistry |
Zhang Q.,Suzhou University of Science and Technology |
Zhang Y.,Institute of Analytical Chemistry |
Tu Y.,Institute of Analytical Chemistry
Analytical Sciences | Year: 2010
A capillary electrophoresis with electrochemical detection was developed for the simultaneous determination of three flavonoids (naringenin, rutin, quercetin) and ascorbic acid. It was found that naringenin, rutin, quercetin and ascorbic acid were well separated within 5 min in borate buffer solution (pH 8.6, 24 mM). The detection limit was 1.0 μM for naringenin, 8.0 μM for rutin, 2.0 μM for ascorbic acid and 0.5 μM for quercetin. The protocol was successfully applied for the determination of the analytes in rat serum and excrement. Recovery results ranged from 90.9 to 108.6%. 2010 © The Japan Society for Analytical Chemistry.
Rathsack P.,German Center for Energy Resources |
Otto M.,Institute of Analytical Chemistry
Fuel | Year: 2014
The depletion of fossil fuels like crude oil or natural gas in foreseeable future urges the search for alternative fuels. Alternative resources for the production of fuels are biomass or coal, which have already been the feedstock for the chemical industry decades ago. One way for the production of fuels from theses feedstocks is pyrolysis and current research focuses on the influence of process parameters on composition of liquids from pyrolysis and the optimization of the properties necessary for the proposed utilization. To unravel the chemical composition of these oils, high performance instrumental analytical methods like comprehensive gas-chromatography mass-spectrometry (GC×GC-MS) are highly beneficial. Unfortunately obtained data sets are very complex and dedicated interpretation methods are needed. In this study, the classification of about thousand compounds in a GC×GC-MS chromatogram of a brown coal pyrolysis oil is demonstrated by means of linear discriminant analysis. Based on a reference compound training set, the compound classes alkanes, alkenes, thiophenes, and benzothiophenes could be assigned with low classification error. This will help in the understanding of the influence of process parameters and feedstocks on the composition of pyrolysis oils. © 2013 Elsevier Ltd. All rights reserved.