Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Faden, F.; Mielke, S.; Lange, D.; Dissmeyer, N.;Generic tools for conditionally altering protein abundance and phenotypes on demandBiol. Chem.395737-762(2014)DOI: 10.1515/hsz-2014-0160
Conditional gene expression and modulating protein stability under physiological conditions are important tools in biomedical research. They led to a thorough understanding of the roles of many proteins in living organisms. Current protocols allow for manipulating levels of DNA, mRNA, and of functional proteins. Modulating concentrations of proteins of interest, their post-translational processing, and their targeted depletion or accumulation are based on a variety of underlying molecular modes of action. Several available tools allow a direct as well as rapid and reversible variation right on the spot, i.e., on the level of the active form of a gene product. The methods and protocols discussed here include inducible and tissue-specific promoter systems as well as portable degrons derived from instable donor sequences. These are either constitutively active or dormant so that they can be triggered by exogenous or developmental cues. Many of the described techniques here directly influencing the protein stability are established in yeast, cell culture and in vitro systems only, whereas the indirectly working promoter-based tools are also commonly used in higher eukaryotes. Our major goal is to link current concepts of conditionally modulating a protein of interest’s activity and/or abundance and approaches for generating cell and tissue types on demand in living, multicellular organisms with special emphasis on plants.
Bücher und Buchkapitel
Obst, K.; Sung, T. V.; Anh, N. T.; Trai, N. V.; Porzel, A.; Mundt, S.; Paetz, S.; Reichelt, N. V.; Engel, K.-H.; Ley, J. P.; Wessjohann, L.;Isolation and characterization of sweet-tasting Dammaran-type glycosides from Mycetia balansaeHofmann, T., et al., eds.283-287(2014)
Degenhardt, A.; Wittlake, R.; Seilwind, S.; Liebig, M.; Runge, C.; Hilmer, J.-M.; Krammer, G.; Gohr, A.; Wessjohann, L.;Quantification of Important Flavor Compounds in Beef Stocks and Correlation to Sensory Results by “Reverse Metabolomics”Ferreira, V. & Lopez, R., eds.15-19(2014)ISBN:9780124017245DOI: 10.1016/B978-0-12-398549-1.00003-9
The meaningful correlation of sensory data with analytical data is one of the most challenging tasks in flavor research. In beef stocks in particular, due to the presence of low levels of aroma-active compounds and the taste contribution of non-volatile molecules to the typical “juiciness” character, the consumer encounters a complex matrix situation. The goal of our study was to carry out a comprehensive analysis of all relevant flavor molecules and the correlation to human sensory data.A technique recently developed at the IPB and termed “reverse metabolomics” was used to link biological activity (i.e., sensory data) with variations in the metabolic profile (i.e., analytical data). We used this methodology for the first time to correlate sensorial attributes and GC-MS, LC-MS, and NMR data in culinary beef stocks.Reverse metabolomics was applied to study the link between sensory and chemical composition in a series of freshly prepared culinary beef stocks. A set of 10 different beef stocks was prepared. The degree of liking of the samples was recorded on a hedonic 1–9 scale. Analysis of the stocks was performed by LC-MS, GC-MS, and NMR. 1H-NMR data directly obtained from the meat stock were very complex.Analysis of this dataset by reverse metabolomics revealed some basic structural elements of the key taste compounds, such as carnosine or anserine. The reverse metabolomics correlation of quantitative data with partiality revealed the importance of a set of compounds. This relevance of these compounds has been confirmed by additional sensory experiments which showed an increase in perceived juiciness.
Bücher und Buchkapitel
Bojahr, J.; Obst, K.; Brockhoff, A.; Reichelt, K.; Brandt, W.; Pienkny, S.; Ley, J. P.; Wessjohann, L.; Meyerhof, W.;Interaction of novel sweeteners from Mycetia balansae with the human sweet taste receptorHofmann, T., et al., eds.253-257(2014)
In times where overweight and diabetes are major health issues, the demand for taste–optimized low-calorie sweeteners and sweetness enhancers is increasing. The consumer’s preference for natural food ingredients has enforced the search for natural sweeteners. A potential source of such a natural non-nutritive sweetener is the Vietnamese plant Mycetia balansae, which is used for sweetening by locals. We have identified the sweet principle of Mycetia balansae using sensory-guided analysis and characterized its action on the human sweet taste receptor with an integrated approach combining homology modelling and cell-based functional receptor expression.