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Updated: Feb 4, 2026

Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
Broad substrate specificity of a hyperthermophilic α-glucosidase from Pyrobaculum arsenaticum
Jong-Hyun Jung1,2, Dong-Ho Seo1,3, James F Holden4
11Graduate School of Biotechnology and Institute of Life Science and Resources, Kyung Hee University, Yongin, Gyeonggi, 17140 Korea.
Abstract:
Pyrobaculum arsenaticum is a hyperthermophilic archaeon that thrives at 95°C. This strain encodes a putative GH31 intracellular α-glucosidase (Pars_2044, PyAG) in its genome. The recombinant PyAG (rPyAG) was optimally expressed in Escherichia coli at 37°C for 4 h after IPTG induction. The purified rPyAG is a homotetrameric α-glucosidase that exhibited highly thermostable properties. Maximum p-nitrophenyl-α-D-glucopyranoside (pNPG) hydrolysis activity was observed at 90°C and pH 5.0. The enzyme mainly recognized the non-reducing end of the substrate, releasing the glucose unit. rPyAG also had broad substrate specificity, cleaving maltose (α-1,4-linkage), kojibiose (α-1,2-linkage), and nigerose (α-1,3-linkage) with similar efficiency. Based on these results, rPyAG can be used to modify health-relevant sugar conjugates linked by α-1,2- or α-1,3-bonds.
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