Characterization of a recombinant β-xylosidase of GH43 family from Bacteroides ovatus strain ATCC 8483

Abstract

A novel β-1,4-xylosidase was identified from the genome of Bacteroides ovatus strain ATCC 8483 and overexpressed in Escherichia coli BL21 (DE3) cells. The molecular weight of recombinant enzyme named BoXyl43A was calculated to be 37.1 kDa. Using p-nitrophenyl-β-D-xylopyranoside (pNPβXyl) as substrate, BoXyl43A was most active at pH 7.0 and 35 °C. The enzyme could be activated by Mg²⁺ and Mn²⁺. The K_m and V_max of BoXyl43A against pNPβXyl were 1.71 ± 0.21 mM, 7.41 ± 0.81 μmol/min/mg, respectively. BoXyl43A hydrolyzed xylooligosaccharide to produce D-xylose as main product, indicating that BoXyl43A acted as an exo-β-1,4-xylosidase. The mixture of BoXyl43A and PoAbf62A (α-L-arabinofuranosidase) exhibited significant synergistic effects on the degradation of arabinoxylan. Therefore, BoXyl43A would be a useful tool to degrade hemicellulose.

Keywords:

• Bacteroides ovatus
• β-1,4-xylosidase
• GH family 43

Disclosure statement

The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

This work was supported by the Key Scientific Program of Changchun City (No. 16CX20).