A Novel Highly Thermostable Multifunctional Beta-Glycosidase from Crenarchaeon Acidilobus saccharovorans.

ABSTRACT: We expressed a putative ?-galactosidase Asac_1390 from hyperthermophilic crenarchaeon Acidilobus saccharovorans in Escherichia coli and purified the recombinant enzyme. Asac_1390 is composed of 490 amino acid residues and showed high sequence similarity to family 1 glycoside hydrolases from various thermophilic Crenarchaeota. The maximum activity was observed at pH 6.0 and 93°C. The half-life of the enzyme at 90°C was about 7 hours. Asac_1390 displayed high tolerance to glucose and exhibits hydrolytic activity towards cellobiose and various aryl glucosides. The hydrolytic activity with p-nitrophenyl (pNP) substrates followed the order pNP-?-D-galactopyranoside (328?U?mg(-1)), pNP-?-D-glucopyranoside (246?U?mg(-1)), pNP-?-D-xylopyranoside (72?U?mg(-1)), and pNP-?-D-mannopyranoside (28?U?mg(-1)). Thus the enzyme was actually a multifunctional ?-glycosidase. Therefore, the utilization of Asac_1390 may contribute to facilitating the efficient degradation of lignocellulosic biomass and help enhance bioconversion processes.

SUBMITTER: Gumerov VM 

PROVIDER: S-EPMC4619763 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature