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bioRxiv · 10.1101/2022.03.21.485099

Dual-Resolving of Lipid Positional and Geometric Isomers of C=C Bonds via Bifunctional Photocycloaddition-Photoisomerization Reaction System and Mass Spectrometry

Feng, G.·Gao, M.·Wang, L.·Chen, J.·Hou, M.·Wan, Q.·Lin, Y.·Xu, G.·Qi, X.·Chen, S.
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Abstract

The biological functions of lipids largely depend on their chemical structures. The position and configuration of C=C bonds are two of the essential attributes that determine the structures of unsaturated lipids. However, simultaneous identification of both attributes remains challenging. Here, we developed a bifunctional visible-light-activated photocycloaddition-photoisomerization reaction system, which enabled the dual-resolving of the positional and geometric isomerism of C=C bonds in lipids when combined with liquid chromatographic mass spectrometry. The dual-pathway reaction mechanism was demonstrated by experiments and density functional theory calculations. Based on this bifunctional reaction system, a workflow of deep structural lipidomics was established, and allowed the revealing of unique patterns of cis-trans-isomers in bacteria, as well as the tracking of C=C positional isomers changes in mouse brain ischemia. This study not only offers a powerful tool for deep lipid structural biology, but also provides a new paradigm for developing the multifunctional visible-light-induced reaction.

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Feng, G., Gao, M., Wang, L., Chen, J., Hou, M., Wan, Q., Lin, Y., Xu, G., Qi, X., Chen, S.. 2022-03-22. Dual-Resolving of Lipid Positional and Geometric Isomers of C=C Bonds via Bifunctional Photocycloaddition-Photoisomerization Reaction System and Mass Spectrometry. https://doi.org/10.1101/2022.03.21.485099

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