Reviews & Perspectives
Recent Advances in Software Tools for More Generic and Precise Intact Glycopeptide Analysis
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.Recent Advances in Analytical Approaches for Glycan and Glycopeptide Quantitation
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.Developments in Mass Spectrometry for Glycosaminoglycan Analysis: A Review
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.Meta-heterogeneity: Evaluating and Describing the Diversity in Glycosylation Between Sites on the Same Glycoprotein
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.
