- 著者
-
Atsushi Kawano
Kansuke Fukui
Yuji Matsumoto
Atsushi Terada
Akihiro Tominaga
Nozomi Nikaido
Takashi Tonozuka
Kazuhide Totani
Nozomu Yasutake
- 出版者
- The Japanese Society of Applied Glycoscience
- 雑誌
- Journal of Applied Glycoscience (ISSN:13447882)
- 巻号頁・発行日
- pp.jag.JAG-2019_0015, (Released:2020-03-06)
- 被引用文献数
-
9
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.