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Computational mass spectrometry accelerates C=C position-resolved untargeted lipidomics using oxygen attachment dissociation

ABSTRACT: Mass spectrometry-based untargeted lipidomics has revealed the lipidome atlas of living organisms at the molecular species level. Despite the double bond (C=C) position being a crucial factor for enzyme preference, cellular membrane milieu, and biological activity, the C=C defined structures have not yet been characterized. Here, we present a novel approach for C=C position-resolved untargeted lipidomics using a combination of oxygen attachment dissociation and computational mass spectrometry to increase the rate of annotation. We validated the accuracy of our platform as per the authentic standards of 21 lipid subclasses and the biogenic standards of 51 molecules containing polyunsaturated fatty acids (PUFAs) from the cultured cells fed with various fatty acid-enriched media. By analyzing human and mice-derived biological samples, we characterized 675 unique lipid structures with the C=C position-resolved level encompassing 22 lipid subclasses defined by LIPID MAPS. Our platform also illuminated the unique profiles of tissue-specific lipids containing n-3 and/or n-6 very long-chain PUFAs (carbon M 28 and double bonds a 4) in the eye, testis, and brain of the mouse.

INSTRUMENT(S): Liquid Chromatography MS - negative - reverse phase, Liquid Chromatography MS - positive - reverse phase

SUBMITTER: Haruki Uchino

PROVIDER: MTBLS5861 | MetaboLights | 2022-11-09

REPOSITORIES: MetaboLights

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			Action	DRS
	MTBLS5861	Other
	FILES	Other
	a_MTBLS5861_LC-MS_cid_negative_reverse-phase_metabolite_profiling.txt	Txt
	a_MTBLS5861_LC-MS_cid_positive_reverse-phase_metabolite_profiling.txt	Txt
	a_MTBLS5861_LC-MS_oad_positive_reverse-phase_metabolite_profiling.txt	Txt

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Project description:Lipid Data Analyzer (LDA; http://genome.tugraz.at/lda2) provides automated and reliable annotation of lipid species and their molecular structures in high-throughput data from chromatography-coupled tandem mass spectrometry using embedded rule sets. Using various low- and high-resolution mass spectrometry instruments with several collision energies, the method's platform independence is proved. The software's reliability, flexibility, and ability to identify novel lipid molecular species may now render current state-of-the-art lipid libraries obsolete. The basic fragment rules are based on published results. From the experimental data, the rules were adapted and extended by visual inspection of spectra. Detectable fragments, mandatory fragment derived intensity rules, and extracted decisive differences for many isobaric subclasses/adducts were all identified. In addition, intensity relationships characteristic for sn-position assignment were determined. Control experiment 1 assays can be found in the current study MTBLS394.Control experiment 2 assays can be found in study <a href='https://www.ebi.ac.uk/metabolights/MTBLS391' rel='noopener noreferrer' target='_blank'>MTBLS391</a>.Control experiment 3 assays can be found in study <a href='https://www.ebi.ac.uk/metabolights/MTBLS398' rel='noopener noreferrer' target='_blank'>MTBLS398</a>.Murine liver lipidome experiment assays can be found in study <a href='https://www.ebi.ac.uk/metabolights/MTBLS396' rel='noopener noreferrer' target='_blank'>MTBLS396</a>.LipidBlast benchmarking assays can be found in study <a href='https://www.ebi.ac.uk/metabolights/MTBLS397' rel='noopener noreferrer' target='_blank'>MTBLS397</a>.HCD characterization and regioisomer detection assays can be found in study <a href='https://www.ebi.ac.uk/metabolights/MTBLS462' rel='noopener noreferrer' target='_blank'>MTBLS462</a>.

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Computational mass spectrometry accelerates C=C position-resolved untargeted lipidomics using oxygen attachment dissociation

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