Glycosylation as means of reducing sample complexity to enable quantitative proteomics

Quantitative proteomics is a rapidly expanding field, in particular, the application to clinical biomarker studies for diagnosis or prognosis of diseases, and the systematic analysis of protein functions in biological systems. Isolation of a class of peptides or a subproteome enables reduction of sample complexity, which is essential to perform sensitive, quantitative analyses over a wider dynamic range of protein concentrations. Glycosylation is one of the most frequent PTMs, and glycans have unique chemical properties that can be leveraged to selectively enrich for a subset of peptides, and thus facilitate the downstream analysis. The isolation of glycopeptides and its benefits for mass spectrometric measurements is discussed.