Bioguided phytochemical studies in Peperomia obtusifolia led to the isolation of a series of bioactive secondary metabolites, including prenylated chromanes, lignans, amides, flavonoids and other phenolic derivatives. The prenylated chromanes showed potent trypanocidal activity. Based on a literature survey, the prenylated compounds seem to be responsible for most of the biological activities reported in Peperomia. Additionally, the prenylated benzopyrans were isolated as racemic and/or diastereomeric mixtures, which raises questions about the level of stereochemical control in the addition of prenyl units as well as the cyclization and formation of the 3,4-dihydro-2H-pyran ring. Thus, this project aims to identify the protein profile of this species and the consequent development of proteomic reference maps, complementing previous results regarding the in vitro activity of oxidoreductases, PAL, prenyl- and geranyltransferases in Piperaceae species. The proteomics analysis will be carried out in three main steps: extraction, analysis and identification of proteins. The extraction of the protein complex will be performed based on protocols already established by the research group headed by Prof. Furlan. The structural analysis and the identification of proteins will be made by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MALDI-TOF or ESI-MS / MS). Chromatographic techniques such as ion chromatography using adsorbents, gel filtration and electrophoresis will be used for the fractionation and purification of the proteins of interest. The secondary structure of isolated proteins will be determined by using vibrational circular dichroism (VCD) spectroscopy.
News published in Agência FAPESP Newsletter about the scholarship: