A simple analytical workflow is described for gas chromatographic-mass spectrometric (GC-MS)-based chiral profiling of secondary amino acids (AAs) in biological matrices. The sample preparation is carried out directly in aqueous biological sample extracts and involves in situ heptafluorobutyl chloroformate (HFBCF) derivatization-liquid-liquid microextraction of nonpolar products into hexane phase followed by subsequent formation of the corresponding methylamides from the HFB esters by direct treatment with methylamine reagent solution. The (O, N) HFB-butoxycarbonyl-methylamide AA products (HFBOC-MA) are separated on a Chirasil-L-Val capillary column and quantitatively measured by GC-MS operated in selected ion monitoring (SIM) mode.
View Article and Find Full Text PDFMultidimensional chromatography offers enhanced chromatographic resolution and peak capacity, which are crucial for analyzing complex samples. This study presents a novel comprehensive online multidimensional chromatography method for the lipidomic analysis of biological samples, combining lipid class and lipid species separation approaches. The method combines optimized reversed-phase ultrahigh-performance liquid chromatography (RP-UHPLC) in the first dimension, utilizing a 150 mm long C18 column, with ultrahigh-performance supercritical fluid chromatography (UHPSFC) in the second dimension, using a 10 mm long silica column, both with sub-2 μm particles.
View Article and Find Full Text PDFRibosomally synthesized and post-translationally modified peptides (RiPPs) are intriguing compounds with potential pharmacological applications. While many RiPPs are known as antimicrobial agents, a limited number of RiPPs with anti-proliferative effects in cancer cells are available. Here we report the discovery of nostatin A (NosA), a highly modified RiPP belonging among nitrile hydratase-like leader peptide RiPPs (proteusins), isolated from a terrestrial cyanobacterium sp.
View Article and Find Full Text PDFActivation of immune cells requires the remodeling of cell metabolism in order to support immune function. We study these metabolic changes through the infection of Drosophila larvae by parasitoid wasp. The parasitoid egg is neutralized by differentiating lamellocytes, which encapsulate the egg.
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