Structural and functional characterization of a multi-domain GH92 α-1,2-mannosidase from Neobacillus novalis.

Many secreted eukaryotic proteins are N-glycosylated with oligosaccharides composed of a high-mannose N-glycan core and, in the specific case of yeast cell-wall proteins, an extended α-1,6-mannan backbone carrying a number of α-1,2- and α-1,3-mannose substituents of varying lengths. α-Mannosidases from CAZy family GH92 release terminal mannose residues from these N-glycans, providing access for the α-endomannanases, which then degrade the α-mannan backbone. Most characterized GH92 α-mannosidases consist of a single catalytic domain, while a few have extra domains including putative carbohydrate-binding modules (CBMs).

Analysis of fungal high-mannose structures using CAZymes.

Glycoengineering ultimately allows control over glycosylation patterns to generate new glycoprotein variants with desired properties. A common challenge is glycan heterogeneity, which may affect protein function and limit the use of key techniques such as mass spectrometry. Moreover, heterologous protein expression can introduce nonnative glycan chains that may not fulfill the requirement for therapeutic proteins.

Removal of -linked glycans in cellobiohydrolase Cel7A from reveals higher activity and binding affinity on crystalline cellulose.

Background: Cellobiohydrolase from glycoside hydrolase family 7 is a major component of commercial enzymatic mixtures for lignocellulosic biomass degradation. For many years, Cel7A (Cel7A) has served as a model to understand structure-function relationships of processive cellobiohydrolases. The architecture of Cel7A includes an -glycosylated catalytic domain, which is connected to a carbohydrate-binding module through a flexible, -glycosylated linker.