Better together - Relative retention time plus spectral matching improves automated glycan characterization using PGC-nLC-IT-ESI-MS/MS

Alagesan, K.; Schirmeister, F.; Moeginger, U.; Everest-Dass, A.; Altmann, F.; Seeberger, P. H.; von Itzstein, M.; Packer, N. H.; Kolarich, D.

doi:10.1101/2021.08.04.451140

bioRxiv · 10.1101/2021.08.04.451140

Better together - Relative retention time plus spectral matching improves automated glycan characterization using PGC-nLC-IT-ESI-MS/MS

Alagesan, K.·Schirmeister, F.·Moeginger, U.·Everest-Dass, A.·Altmann, F.·Seeberger, P. H.·von Itzstein, M.·Packer, N. H.·Kolarich, D.

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Abstract

Porous Graphitized Carbon nano-liquid chromatography tandem mass spectrometry (PGC-nLC-MS/MS) is a glycomics technique with the unique capacity to differentiate isobaric glycans. The lack of suitable software tools integrating chromatography and MS-information delivered by PGC-nLC-MS/MS has been limiting fast and robust glycan identification and quantitation. We report a LC-system-independent strategy called GlycoRRT that combines relative retention time (RRT) and negative ion fragment spectra analyses for isobaric structure-specific glycomics of PGC-nLC-MS/MS data. The GlycoRRT toolset is fully customizable and easily adaptable enabling semi-automated high-throughput structural assignments. The current library contains over 200 entries and their individual meta-data (MS instrumentation, experimental conditions, retention times, fragmentation profiles and glycan structural diagnostic ion features) relevant for reliable data analyses. The GlycoRRT workflow was employed to map the N- and O-glycome in blood group matched human plasma and urine as well as decipher Immunoglobulin (IgG) glycosylation features from 13 different animal species. We have also developed visualization tools to enable a consistent, reliable, and reproducible analysis of large sets of multidimensional PGC-nLC-MS/MS glycomics data. This comprehensive glycan resource provides the glycan map of human and animal species, will serve as a reference in dissecting the role of glycans in host pathogen interaction and zoonotic disease transmission.

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Alagesan, K., Schirmeister, F., Moeginger, U., Everest-Dass, A., Altmann, F., Seeberger, P. H., von Itzstein, M., Packer, N. H., Kolarich, D.. 2021-08-04. Better together - Relative retention time plus spectral matching improves automated glycan characterization using PGC-nLC-IT-ESI-MS/MS. https://doi.org/10.1101/2021.08.04.451140

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