Effective Chemical and Enzymatic Methods to Globally Characterize Protein Glycosylation

Protein glycosylation is ubiquitous in biological systems and essential for cell survival. Aberrant protein glycosylation is directly related to human disease, including cancer and infectious diseases, and glycoproteins contain a wealth of information related to developmental and disease statuses of cells. However, due to the low abundance of many glycoproteins and heterogeneity of glycans, it is extraordinarily challenging to comprehensively analyze glycoproteins in complex biological samples. Based on the common features of glycans, we have developed chemical and enzymatic methods to globally analyze protein glycosylation by mass spectrometry (MS). Glycoproteins located on the cell surface are especially interesting because they frequently regulate extracellular events. We specifically tagged surface glycoproteins for global and site-specific analysis. In combination with multiplexed proteomics, we quantified the dynamics of surface glycoproteins and measured their half-lives. Global analysis of protein glycosylation leads to a better understanding of glycoprotein functions and the identification of glycoproteins as disease biomarkers and drug targets.
Ronghu Wu (Georgia Institute of Technology)