Protein Glycosylation, an Overview

Abstract

Abstract Glycosylation is the most common post‐translational modification of proteins. It is a complex process involving many functional proteins and resulting in a great diversity of carbohydrate–protein bonds and glycan structures. Biological role of glycosylation and molecular and genetic basis of glycosylation disorders have recently been extensively explored. Glycosylation of some proteins has a great impact on their structures and functions, and interactions of protein‐linked glycans with carbohydrate‐specific proteins (lectins) modulate many important biological processes. Alterations in glycosylation occur in many pathological states, and genetically determined defects in glycosylation are the reason of severe diseases. The goal of this short article is to signalise the variety of problems of this vast field of research. Key Concepts: Glycosylation is one of the most important posttranslational modification of proteins. There are various types of carbohydrate–protein glycosidic linkage and a great variety of structures of protein‐linked oligosaccharides (glycans). The glycosylation process involves multiple proteins which are direct products of genes. Protein‐linked glycans, as indirect gene products, show microheterogeneity, in qualitative and quantitative sense. Glycosylation of proteins has a great biological significance, carbohydrate–protein interactions are involved in many biological precesses. Alterations of glycosylation in many diseases are used for diagnostic and prognostic purposes. Genetically‐based defects in protein glycosylation are the reason of severe diseases that is a direct evidence for the importance of glycosylation. Various glycosylation pathways are studied as potential targets for therapeutic purposes.