MS Analysis Expert

Among various post-translational modifications of proteins, glycosylation is one of the most important and complex modifications, and it is also one of the key quality attributes to evaluate antibodies. The realization of the function of monoclonal antibody is closely related to its glycosylation, which will affect the performance of protein, such as conformation, stability, solubility, pharmacokinetics, activity and immunogenicity. Glycosylation is one of the important post-translational modifications of proteins. According to the modified sites of glycosylation, it can be divided into N-glycosylation and O-glycosylation. N-glycosylation is located in asn-297. N-acetylglucosamine in oligosaccharide links itself with  amide nitrogen on asparagine residue  to  modify   protein ,which start s  from endoplasmic reticulum and complete s  in Golgi body .  O-glycosylation is completed in Golgi body by n-acetylgalactose in oligosaccharide linking with ...

Although significant advances have been made in genomics, metabolomics, protein and lipid research, glycosylation has not been widely explored at the proteome level. Techniques for analyzing complex glycoproteomes are limited. Glycoproteins differ not only in the number and location of glycosyl groups, but also in the composition and structure of each glycan. Glycoproteomics is one of the most important frontiers in life sciences. In order to overcome the technical limitations in this field, in a new study, Dr. Josef Penninger, director of the Institute of Molecular Biotechnology (IMBA) of the Austrian Academy of Sciences, and his team developed mass spectrometry and algorithms to finally synthesize complex sugar structures and map them to the correct sites for the corresponding glycoprotein. Their newly developed comparative glycoproteomics platform was published online on September 20, 2017 in the journal Nature, entitled Comparative glycoproteomics of stem cells labeled new pla...

Glycosylation is an important  post-translational modification of p roteins. Glycosylation of proteins can be classified into N-glycosylation and O-glycosylation depending on the manner in which the sugar chain and the peptide chain are linked. N-glycosylation is linked by the N-acetylglucosamine (Glc-NAc) at the reducing end of the sugar chain to the nitrogen atom on the side chain acylamino group of some Asn in the peptide chain. The Asn which can be attached to the sugar chain must be in the motif consisting of the Asn-X-Ser/Thr 3 residue, where X can be any amino acid residue other than Pro. The structure of O-glycosylation is simpler than N-glycosylation, and the sugar chain is generally shorter, but the species is much more numerous than N-glycosylation. The main glycosylation in the peptide chain is Ser and Thr, in addition to tyrosine, hydroxylysine and hydroxyproline, and the linked sites are the hydroxyl oxygen atoms on the side chains of these residues. Based on t...