JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 2015, Vol. 39 ›› Issue (06): 35-39.doi: 10.3969/j.issn.1000-2006.2015.06.007

Previous Articles     Next Articles

Molecular cloning and expression of a novel β-galactosidase from Bacillus coagulans

ZHENG Zhaojuan, XU Ying, SHI Lei, OUYANG Jia*   

  1. College of Chemical Engineering, Nanjing Forestry University, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, Nanjing 210037, China
  • Online:2015-11-30 Published:2015-11-30

Abstract: A novel β-galactosidase gene was cloned from Bacillus coagulans NL01 which had ability to hydrolyze lactose into glucose and galactose in this study. The length of the β-galactosidase gene was 1 998 bp, and its coding sequence showed very low identity with other reported β-galactosidase. The gene was cloned into pETDuet-1 and expressed in Escherichia coli BL21(DE3). The crude enzyme activity was 119.0 μmol/(min·mg), and the purified enzyme activity was 666.4 μmol/(min·mg)after Ni-NTA purification. It was indicated from the analysis results of the hydrolysis product obtained by the purified β-galactosidase that this novel β-galactosidase presented high activity toward lactose conversion into glucose and galactose.

CLC Number: