RT Journal Article SR Electronic T1 A general approach to explore prokaryotic protein glycosylation reveals the unique surface layer modulation of an anammox bacterium JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.12.03.409086 DO 10.1101/2020.12.03.409086 A1 Martin Pabst A1 Denis Grouzdev A1 Christopher E. Lawson A1 Hugo B.C. Kleikamp A1 Carol de Ram A1 Rogier Louwen A1 Yuemei Lin A1 Sebastian Lücker A1 Mark C.M. van Loosdrecht A1 Michele Laureni YR 2020 UL http://biorxiv.org/content/early/2020/12/03/2020.12.03.409086.abstract AB The enormous chemical diversity and strain variability of prokaryotic protein glycosylation makes a large-scale exploration exceptionally challenging. Therefore, despite the universal relevance of protein glycosylation across all domains of life, the understanding of their biological significance and the evolutionary forces shaping oligosaccharide structures remains highly limited.Here, we report on a newly established mass binning glycoproteomics approach that establishes the chemical identity of the carbohydrate components and performs untargeted exploration of prokaryotic oligosaccharides from large-scale proteomics data directly. We demonstrate our approach by exploring an enrichment culture of the globally relevant anaerobic ammonium-oxidizing bacterium Ca. Kuenenia stuttgartiensis. By doing so we resolved a remarkable array of oligosaccharides, produced by two entirely unrelated glycosylation machineries targeting the same surface-layer protein (SLP) simultaneously. More intriguingly, the investigated strain also accomplished modulation of highly specialized sugars, supposedly in response to its energy metabolism—the anaerobic oxidation of ammonium —which depends on the acquisition of substrates of opposite charge. Ultimately, we provide a systematic approach for the compositional exploration of prokaryotic protein glycosylation, and reveal for the first time a remarkable balance between maximising cellular protection through a complex array of oligosaccharides and adhering to the requirements of the ‘metabolic lifestyle’.Competing Interest StatementThe authors have declared no competing interest.