Rapid Profiling of Bovine and Human Milk Gangliosides by Matrix-Assisted Laser Desorption/Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

摘要: Gangliosides are anionic glycosphingolipids widely distributed in vertebrate tissues and fluids. Their structural quantitative expression patterns depend on phylogeny distinct down to the species level. In milk, gangliosides exclusively associated with milk fat globule membrane. They may participate diverse biological processes but more specifically host-pathogen interactions. However, due molecular complexities, analysis needs extensive sample preparation, chromatographic separation, even chemical reaction, which makes process very complex time-consuming. Here, we describe a rapid profiling method for bovine human employing matrix-assisted desorption/ionization (MALDI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS). Prior analyses of samples, ganglioside standards GM3 GD3 fractions were first analyzed order validate this method. High accuracy high resolution obtained from MALDI FTICR MS allow confident assignment chain length degree unsaturation ceramide. For elucidation, tandem (MS/MS), as collision-induced dissociation (CID) infrared multiphoton (IRMPD) employed. Complex mixtures further The samples prepared by two consecutive chloroform/methanol extraction solid phase extraction. We observed number differences between milk. common NeuAc-NeuAc-Hex-Hex-Cer (GD3) NeuAc-Hex-Hex-Cer (GM3); whereas, intensities different samples. Kendrick defect plot yields grouping peaks according their similarities. probed confirm compositional assignments. found that only was ceramide carbon always numbered, is consistent notion oligosaccharide moieties confer physiological distinctions.