Molecular lipid species composition of FusMidp-vesicles and the donor TGN/E. Quantitative lipidomic analysis of FusMidp-vesicles and the TGN/E allowed absolute quantification of 83 molecular lipid species. Lipid composition is shown in mole percentage to demonstrate the stoichiometric relationship between the lipid species (n = 4 independent experiments; mean estimate ± SD). Chemical structures of membrane lipids are illustrated on the right. Lipid species are annotated by their molecular composition (see Materials and methods). Cer, ceramide; PG, phosphatidylglycerol.