High-level expression and characterization of Aspergillus niger ATCC 1015 xylanase B in Komagataella phaffii

Owing to the safety issues in food and feed industry, the GH11 xylanase B gene from Aspergillus niger ATCC 1015 was cloned and expressed in Komagataella phaffii. The highest xylanase B activity of 1827.19 U/ml was obtained after optimization of temperature, pH, and methanol addition through flask cultivation. The optimal temperature and pH were 55 °C and 5.0, respectively, and the highest relative activity of xylanase B reached 133.20% with the addition of 10 mmol/l cupric ions. Thus, the high-level recombinant xylanase B obtained in this study could have potential applications in food and feed industry.