Analysis of Transglucosylation Products of Aspergillus niger α-Glucosidase that Catalyzes the Formation of α-1,2- and α-1,3-Linked Oligosaccharides
| Autor: | Atsushi Kawano, Nozomi Nikaido, Atsushi Terada, Kansuke Fukui, Yuji Matsumoto, Nozomu Yasutake, Kazuhide Totani, Takashi Tonozuka, Akihiro Tominaga |
|---|---|
| Rok vydání: | 2020 |
| Předmět: | |
| Zdroj: | Journal of Applied Glycoscience. 67:41-49 |
| ISSN: | 1880-7291 1344-7882 |
| Popis: | According to whole-genome sequencing, Aspergillus niger produces multiple enzymes of glycoside hydrolases (GH) 31. Here we focus on a GH31 α-glucosidase, AgdB, from A. niger . AgdB has also previously been reported as being expressed in the yeast species, Pichia pastoris ; while the recombinant enzyme (rAgdB) has been shown to catalyze tranglycosylation via a complex mechanism. We constructed an expression system for A. niger AgdB using Aspergillus nidulans . To better elucidate the complicated mechanism employed by AgdB for transglucosylation, we also established a method to quantify glucosidic linkages in the transglucosylation products using 2D NMR spectroscopy. Results from the enzyme activity analysis indicated that the optimum temperature was 65 °C and optimum pH range was 6.0-7.0. Further, the NMR results showed that when maltose or maltopentaose served as the substrate, α-1,2-, α-1,3-, and small amount of α-1,1-β-linked oligosaccharides are present throughout the transglucosylation products of AgdB. These results suggest that AgdB is an α-glucosidase that serves as a transglucosylase capable of effectively producing oligosaccharides with α-1,2-, α-1,3-glucosidic linkages. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|