Role of N-linked glycosylation in the enzymatic properties of a thermophilic GH 10 xylanase from Aspergillus fumigatus expressed in Pichia pastoris.

ABSTRACT: N-Glycosylation is a posttranslational modification commonly occurred in fungi and plays roles in a variety of enzyme functions. In this study, a xylanase (Af-XYNA) of glycoside hydrolase (GH) family 10 from Aspergillus fumigatus harboring three potential N-glycosylation sites (N87, N124 and N335) was heterologously produced in Pichia pastoris. The N-glycosylated Af-XYNA (WT) exhibited favorable temperature and pH optima (75°C and pH 5.0) and good thermostability (maintaining stable at 60°C). To reveal the role of N-glycosylation on Af-XYNA, the enzyme was deglycosylated by endo-β-N-acetylglucosaminidase H (DE) or modified by site-directed mutagenesis at N124 (N124T). The deglycosylated DE and mutant N124T showed narrower pH adaptation range, lower specific activity, and worse pH and therm

SUBMITTER: Chang X 

PROVIDER: S-EPMC5302446 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature