Glycosylation is an important way in which proteins, the functional agents of our body, can be modified to alter and expand their functional repertoire. Glycans consist of monosaccharides that... Show moreGlycosylation is an important way in which proteins, the functional agents of our body, can be modified to alter and expand their functional repertoire. Glycans consist of monosaccharides that are linked in a chained and branching fashion, often to form specific epitopes that are of clinical and biopharmaceutical interest. In order to study glycosylation, there is a need for high-throughput analysis methodology. Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is a prominent example of this, as it can rapidly provide information on the monosaccharide compositions of glycans. However, it is challenging for the method to yield information on the structural aspects of glycosylation, as well as on glycans carrying sialic acids. These sialylated glycans are prone to in-source and metastable decay, and tend to require chemical derivatization to allow their analysis. The aim of this thesis is the development and application of new methodology for MALDI-MS N-glycomics, and, with a focus on metabolic syndrome and rheumatoid arthritis, to increase our understanding of the role of N-glycosylation in health and disease. A principal outcome of the work is a sialic acid derivatization protocol that allows the mass-based discrimination of alpha-2,3- and alpha-2,6-linked sialic acids, facilitating their study in a high-throughput setting. Show less
This dissertation describes the development of glyco-bioinformatics tools that facilitate the high-throughput data processing of glycomics and glycoproteomics experiments, specifically for both... Show moreThis dissertation describes the development of glyco-bioinformatics tools that facilitate the high-throughput data processing of glycomics and glycoproteomics experiments, specifically for both MALDI-TOF-MS (Chapter 2) and LC-ESI-MS (Chapter 3). The developed methods also provide various quality control parameters that assist the researcher in curating both the measured spectra and quantified analytes, thereby providing high-quality data in a high-throughput manner.The tools that were developed within this thesis have been used to identify the influence of glycosylation on trypsin efficacy of Immunoglobulin G (Chapter 3) and two biological cohorts. Specifically, to investigate the serum N-glycosylation during and after pregnancy (Chapter 5) and to identify the differences in the N-glycosylation between maternal and fetal serum and IgG (Chapter 6). Show less
