Structure-guided engineering of the substrate specificity of a fungal β-glucuronidase toward triterpenoid saponins.

ABSTRACT: Glycoside hydrolases (GHs) have attracted special attention in research aimed at modifying natural products by partial removal of sugar moieties to manipulate their solubility and efficacy. However, these modifications are challenging to control because the low substrate specificity of most GHs often generates undesired by-products. We previously identified a GH2-type fungal β-glucuronidase from Aspergillus oryzae (PGUS) exhibiting promiscuous substrate specificity in hydrolysis of triterpenoid saponins. Here, we present the PGUS structure, representing the first structure of a fungal β-glucuronidase, and that of an inactive PGUS mutant in complex with the native substrate glycyrrhetic acid 3-O-mono-β-glucuronide (GAMG). PGUS displayed a homotetram

SUBMITTER: Lv B 

PROVIDER: S-EPMC5767852 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature