TTCBH6B is active against shorter oligosaccharides rather than polysaccharides.

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 (Glc 1 Man 9 GlcNAc 2) at 100 ml scale. However, it was possible to detect truncated oligomannose (paucimannose) structures in the fOSs of the alg8 mutant.

Unfortunately, Author name ''Mukram Mohamed Mackeen'' had been published incorrectly as ''Mukram MohamedMackeen'' without a space. This error has been rectified in the original article.

The glycomic profiles of free oligosaccharides (fOS) derived from misfolded N-and O-linked glycoproteins and lipidlinked oligosaccharides are important molecular signatures in various biological processes and serve as a readout of functional properties such as glycosidase inhibition. Several glycan extraction methods are available based on different sorbent chemistries that may influence the analytical profiles obtained. However, there is limited availability of studies comparing the effects of sorbent chemistries on glycan profiles. Therefore, in our study, the fOS profiles from wild-type Saccharomyces cerevisiae (Baker's yeast) extracted using two common methods namely mixed-bed ion-exchange (MBIE) [AG50W-X12 (H +) and AG2-X8 (Cl-)] and reversed-phase (C18) sorbents were compared using total carbohydrate (phenol sulfuric acid) and total protein (bicinchoninic acid, BCA) assays, thin-layer chromatography (TLC) and highperformance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) analyses. MBIE extraction contained higher oligosaccharide and protein (0.26 mg/mL and 1.8 mg/mL) content than C18 extraction (0.11 mg/mL and 0.2 mg/mL). TLC analysis (butanol: ethanol: water = 6:3:1 and 5:4:1) showed the presence of fOS in both the MBIE and C18 extracts based on the detection of orcinol active (UV-inactive) spots. Similar peaks were present in the HPLC-ELSD chromatograms for both extractions methods with MBIE showing higher abundance. Glycan unit (GU) analysis of the dextran standard using HPLC-ELSD showed that the largest possible oligosaccharide structures detected were only di/trisaccharides. Based on all these results, MBIE extraction is a more suitable carbohydrate extraction technique compared to C18 extraction for subsequent profiling and functional studies of fOS.