Reviews & Perspectives
- In Brief This article provides a systematic review of the most recent MS-based strategies and corresponding software tools for the analysis of intact glycopeptides, particularly intact N-glycopeptides, reported in the last decade, including the process of identifying N-glycopeptides from MS data, the existing methods of MS data acquisition and interpretation, the quality control methods, the display of results, and the software applications.
- In Brief Recent years have seen an explosion in novel strategies for quantitative glycomics and glycoproteomics. Whether through metabolic incorporation of stable isotopes, deposition of custom isotopic labels, or high-throughput isobaric chemical tags, these numerous novel strategies provide ease of access to glycomic and glycoproteomic investigation. This review highlights the recent innovations in labeling methods, label-free strategies, acquisition modes, and bioinformatic tools for glycan and glycopeptide quantitation, while providing critical evaluations and technical considerations to enable effective analysis.
- In Brief Glycosaminoglycans (GAGs) participate in a variety of biological functions and have a multitude of medicinal properties. Due to their non template driven biosynthesis, GAGs are produced as nonuniform complex mixtures. Mass spectrometry paired with on-line separation techniques has been utilized to determine the composition of these complex mixtures. Advances in tandem mass spectrometry have also made determining sequence information such as sulfation location and C-5 epimerization possible. This review covers recent developments in the analysis of GAGs using mass spectrometry.
- In Brief Diversity in protein glycosylation can be described in terms of micro-heterogeneity and macro-heterogeneity, respectively, referring to the variation and occupancy of glycans at a given glycosylation site. However, these terms are not sufficient to describe a higher level of regulation when proteins are multiply glycosylated. For this, we propose the term meta-heterogeneity: variation in glycosylation across multiple sites of a given glycoprotein. In this review, we describe several remarkable examples of glycoprotein meta-heterogeneity and underline the need for its investigation.