Characterization of a new 1,3-1,4-β-glucanase gene from Bacillus tequilensis CGX5-1.

Abstract

1,3-1,4-β-Glucanase received great interest due to its application in brewing and feed industries. Application of 1,3-1,4-β-glucanase in brewing industry helps make up for the defect that plant-derived β-glucanases are heat-sensitive. A new strain, CGX5-1, exhibited remarkable 1,3-1,4-β-glucanase, was isolated from Asian giant hornet nest and identified Bacillus tequilensis. Moreover, a new 1,3-1,4-β-glucanase gene from B. tequilensis was cloned and measured to be 720bp encoding 239 amino acids, with a predicted molecular weight of 26.9kDa. After expressed in Escherichia coli BL21, active recombinant enzyme of 24kDa was detected in the supernatant of cell culture, with the activity of 2,978.2 U/mL. The new enzyme was stable in the pH5.0-7.5 with the highest activity measured at pH6.0. Moreover, it is thermostable within 45 to 60°C. The property of the new recombinant enzyme makes this enzyme a broad prospect in brewing industry. Moreover, this is the first report on 1,3-1,4-β-glucanase produced by B. tequilensis.