Impact of Yeast Glycosylation Pathway on Cell Integrity and Morphology, Glycosylation, Stefana Petrescu (Ed.), ISBN: 978-953-51-0771-2, InTech, Available from: http://www.intechopen.com/books/glycosylation/impact-of-yeast-glycosylation-pathway-on-cell-integrity-and-morphology

Abstract

Protein glycosylation is a multi step reaction, well conserved in the eukaryotic cells. In N-glycosylation reactions dolichyl phosphate (DolP) serves as a lipid acceptor of sugar residues forming DolPPGlcNAc2Man9Glc3. Dolichyl phosphate mannose (DolPMan) is also a substrate for protein O-glycosylation, where it serves as a donor of the first mannose to be attached to hydroxyl groups of serine or treonine. DolPMan is also involved in the synthesis of the sugar part of glycosylphosphatidyl inositol anchor in yeast and other eukaryotes. Its remnant structure is responsible for the attachment of a large group of glycoproteins to the glucan polymers of the cell wall . Thus, a functional link could be predicted between the dolichol biosynthetic (mevalonate) pathway and subsequent N-glycosylation and O-mannosylation, cell wall assembly and/or fungus–host interaction. Moreover, on the basis of the data presented in this chapter, it can be assumed that the glycosylation pathway in yeast and fungi offers many levels of regulation, which might influence the final quality and quantity of cell wall glycoproteins and consequently cell surface immunogenicity. In this work we concentrate on early glycosylation defects, resulting from the impaired synthesis of dolichol (Dol) and dolichyl phosphate (DolP) or DolPP oligosaccharide (DolPPGlcNAc2Man9Glc3) assembly, and their effect on the cell integrity and morphology.