A Lipid-Atlas of the Model Organism Caenorhabditis elegans

Lipids play important roles in many different aspects of biology. A major model organism to study lipid metabolism is the small nematode Caenorhabditis elegans. Many insights have been generated by the use of GC-MS based analysis of lipid derived fatty acids, but analysis of intact lipid only recently joined the C. elegans toolbox. The worm harbors several peculiarities in its lipid metabolomics, e.g. it uses branched chain fatty acids which are produced almost exclusively (99.9%) by the worm itself. Furthermore, C. elegans uses C15:0iso instead of palmitic acid to produce a C17iso sphingoid base.

These and other features make the C. elegans lipidome distinct from other species (e.g. human, mice) and lipids that occur in C. elegans are only partially covered in lipid databases. Based on a consensus metabolic reconstruction and known lipid biochemistry we have started to generate a stoichiometry model of the worm’s lipid metabolism and predicting potentially present lipids. Known biochemical reactions were used as templates to produce in silico all possible lipids together with their biosynthesis and degradation pathways. The generated database of lipids will serve as future reference for investigations into the lipidome of the worm. We have started to compare predicted lipids with several different lipid extracts from C. elegans measured with UPLC-UHR-ToF-MS.