Quantitative Analyses Reveal Novel Roles for N- Glycosylation in a Major Enteric Bacterial Pathogen

Abstract

Advances in genomics and mass spectrometry have revealed several types of glycosylation systems in bacteria. However, why bacterial proteins are modified remains poorly defined. Here, we investigated the role of general N- linked glycosylation in a major food poisoning bacterium, Campylobacter jejuni . The aim of this study is to delineate the direct and indirect effects caused by disrupting this posttranslational modification. To achieve this, we employed a quantitative proteomic strategy to monitor alterations in the C. jejuni proteome. Our quantitative proteomic results linked general protein N- glycosylation to maintaining proteome stability. Functional analyses revealed novel roles for bacterial N- glycosylation in modulating multidrug efflux pump, enhancing nitrate reduction activity, and promoting host-microbe interaction. This work provides insights on the importance of general glycosylation in proteins in maintaining bacterial physiology, thus expanding our knowledge of the emergence of posttranslational modification in bacteria.