Deciphering lipid structures based on platform-independent decision rules

Abstract

We achieve automated and reliable annotation of lipid species and their molecular structures in high-throughput data from chromatography-coupled tandem mass spectrometry using decision rule sets embedded in Lipid Data Analyzer (LDA; http://genome.tugraz.at/lda2). Using various low- and high-resolution mass spectrometry instruments with several collision energies, we proved the method's platform independence. We propose that the software's reliability, flexibility, and ability to identify novel lipid molecular species may now render current state-of-the-art lipid libraries obsolete.

Figure 1

Tandem mass spectra of lipid molecular species depend on platform and collision energy. Spectra of deprotonated PI 18:0/20:4 from two platforms and two collision energy settings are shown: (a) Orbitrap Velos Pro, CID mode, 30 %, precursor m/z 885.545, damping gas He; (b), 4000 QTRAP, CID mode, 30 eV, precursor m/z 885.93, collision gas N₂; (c) Orbitrap Velos Pro, CID mode, 60 %, precursor m/z 885.549, damping gas He; (d) 4000 QTRAP, CID mode, 60 eV, precursor m/z 885.85, collision gas N₂.