Systematic Screening for Novel Lipids by Shotgun Lipidomics
- Publication date
- 2014
- Publisher
Abstract
A commonly accepted LIPID MAPS classification
recognizes eight
major lipid categories and over 550 classes, while new lipid classes
are still being discovered by targeted biochemical approaches. Despite
their compositional diversity, complex lipids such as glycerolipids,
glycerophospholipids, saccharolipids, <i>etc.</i> are constructed
from unique structural moieties, <i>e.g.</i>, glycerol,
fatty acids, choline, phosphate, and trehalose, that are linked by
amide, ether, ester, or glycosidic bonds. This modular organization
is also reflected in their MS/MS fragmentation pathways, such that
common building blocks in different lipid classes tend to generate
common fragments. We take advantage of this stereotyped fragmentation
to systematically screen for new lipids sharing distant structural
similarity to known lipid classes and have developed a discovery approach
based on the computational querying of shotgun mass spectra by LipidXplorer
software. We applied this concept for screening lipid extracts of <i>C. elegans</i> larvae at the <i>dauer</i> and L3 stages
that represent alternative developmental programs executed in response
to environmental challenges. The search, covering more than 1.5 million
putative chemical compositions, identified a novel class of lyso-maradolipids
specifically enriched in <i>dauer</i> larvae