Update on LIPID MAPS classification, nomenclature, and shorthand notation for MS-derived lipid structures

Abstract

A comprehensive and standardized system to report lipid structures analyzed by mass spectrometry is essential for the communication and storage of lipidomics data. Herein, an update on both the LIPID MAPS classification system and shorthand notation of lipid structures is presented for lipid categories Fatty Acyls (FA), Glycerolipids (GL), Glycerophospholipids (GP), Sphingolipids (SP), and Sterols (ST). With its major changes, i.e. annotation of ring double bond equivalents and number of oxygens, the updated shorthand notation facilitates reporting of newly delineated oxygenated lipid species as well. For standardized reporting in lipidomics, the hierarchical architecture of shorthand notation reflects the diverse structural resolution powers provided by mass spectrometric assays. Moreover, shorthand notation is expanded beyond mammalian phyla to lipids from plant and yeast phyla. Finally, annotation of atoms is included for the use of stable isotope-labelled compounds in metabolic labelling experiments or as internal standards.This update on lipid classification, nomenclature and shorthand annotation for lipid mass spectra is considered a standard for lipid data presentation.

Linking Gut Microbiome and Lipid Metabolism: Moving beyond Associations

“…Recently, several tools such as LION/web [ 125 ], LipidLynxX [ 126 ] and Reference Set of Metabolite Names (RefMet) [ 127 ] have been developed with a view to solving these issues. LION/web [ 125 ] aims to translate and interpret the involvement of lipid species in various biological systems.…”

“…LipidLinxX is a data transfer hub which facilitates integration of large-scale lipidomic datasets by standardizing lipid identifiers to the same level of annotation and thereby facilitate cross-level matching between different datasets [ 126 ]. RefMet seeks to provide unifying nomenclature for the metabolites detected by analytical methods [ 127 ]. Furthermore, Gerhard Liebisch et.al.…”

Sphingolipidomics in Translational Sepsis Research–Biomedical Considerations and Perspectives

“…Other sphingoid bases differ in number of unsaturated bonds (SPHINGANINE d18:0, syn. dihydrosphingosine; SPHINGADIENE d18:2 4,14 ) as well as number and position of hydroxyl groups: PHYTOSPHINGOSINE t18:0 and DEOXYSPHINGOSINE m18:0. Use of alanine instead of serine as a building block in the first condensation step produces deoxysphingosine derivatives (m18:1).…”

“…A plethora of additional variations are found in other organisms (2). Along chemical structures of individual lipids and their derivatives, categorization into distinct classes and subclasses, nomenclature, and cataloging of (sphingo-)lipids and of their properties were performed by the LIPID MAPS Consortium (3), most recently revised by leading authorities in the field (4). Similar to sphingosine, also Cer is phosphorylated to the bioactive lipid mediator Cer-1-phosphate (not shown) (5).…”

“…The most abundant sphingoid base is SPHINGOSINE with an 18-carbon chain, which is hydroxylated at positions 1 and 3 and unsaturated at one double bound (position 4). Written in shorthand for sphingolipidomics, thus sphingosine is d18:1 4 , where the dihydroxylation status is termed by the "d." There are over a dozen variations in the backbone in terms of chain length, saturation (number of double bonds), branching (8), and finally the number and position of hydroxyl substituents ("m" or "t" denotes one or three hydroxyl groups, respectively) (1,2). In mammals, the d18:1 backbone is mostly predominant (9).…”