A high-resolution HPLC-QqTOF platform using parallel reaction monitoring for in-depth lipid discovery and rapid profiling

• Published in: Analytica chimica acta 2018-10, Vol.1026, p.87-100
• Main Authors: Yu, Dingyi, Rupasinghe, Thusitha W.T., Boughton, Berin A., Natera, Siria H.A., Hill, Camilla B., Tarazona, Pablo, Feussner, Ivo, Roessner, Ute
• Format: Article
• Language: English
• Subjects: Abiotic stress; Barley; Cereal crops; Cereals; Chromatography, High Pressure Liquid; Fatty acids; High performance liquid chromatography; Hordeum - chemistry; Inositol; Lipidomics; Lipids; Lipids - analysis; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Monitoring; Parallel reaction monitoring; Quadrupoles; Salt stress; Seeds - chemistry; Sterol composition; Tandem Mass Spectrometry; Workflow
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2018.03.062

Here, we developed a robust lipidomics workflow merging both targeted and untargeted approaches on a single liquid chromatography coupled to quadrupole-time of flight (LC-QqTOF) mass spectrometry platform with parallel reaction monitoring (PRM). PRM assays integrate both untargeted profiling from MS1 scans and targeted profiling obtained from MS/MS data. This workflow enabled the discovery of more than 2300 unidentified features and identification of more than 600 lipid species from 23 lipid classes at the level of fatty acid/long chain base/sterol composition in a barley root extracts. We detected the presence of 142 glycosyl inositol phosphorylceramides (GIPC) with HN(Ac)-HA as the core structure of the polar head, 12 cardiolipins and 17 glucuronosyl diacylglycerols (GlcADG) which have been rarely reported previously for cereal crops. Using a scheduled algorithm with up to 100 precursors multiplexed per duty cycle, the PRM assay was able to achieve a rapid profiling of 291 species based on MS/MS data by a single injection. We used this novel approach to demonstrate the applicability and efficiency of the workflow to study salt stress induced changes in the barley root lipidome. Results show that 221 targeted lipids and 888 unknown features were found to have changed significantly in response to salt stress. This combined targeted and untargeted single workflow approach provides novel applications of lipidomics addressing biological questions. [Display omitted] •A lipidomics workflow merging targeted and untargeted approaches using PRM strategy.•Discovery of 2349 unknown features and 634 known lipid species in barley roots.•Rapid profiling of 291 species based on MS/MS data by a single injection using sPRM.•An application of the workflow on salt stress-induced lipid changes in barley roots.