Summary: | N-glycans are biologically important oligosaccharides associated with the asparagine residue that may exist in protein-bound or unbound forms in all eukaryotes (including yeasts) and some bacteria. The- core structure of these oligosaccharides is based on the trimannosyl chitobiose structure resulting from cellular N-glycosylation. Preparative-scale amounts of these oligosaccharides are important for chemical, structural and functional studies due to their biological significance. Therefore, we explored a biochemical approach of oligosaccharide preparation using mutant-derived monoglucosylated lipid-linked oligosaccharides (LLOs) required for the assembly of N-linked glycoproteins and non-monoglucosylated free-oligosaccharides (fOSs) from misfolded N-linked glycoproteins using an N-glycosylation (alg) mutant of Saccharomyces cerevisiae. Oligosaccharide extracts of fOSs and LLOs from the alg8 S. cerevisiae mutant lacking the ALG8 gene were profiled using fluorescence- and evaporative light scattering-based HPLC. LLOs did not produce accumulated levels of the target mutant- related monoglucosylated (Glc1Man9GlcNAc2) at 100 ml scale. However, it was possible to detect truncated oligomannose (paucimannose) structures in the fOSs of the alg8 mutant.
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