Construction and Secretory Expression of β-Galactosidase Gene from Lactobacillus Bulgaricus in Lactococcus Lactis
- Gene constructs /
- Gene expression /
- Secretory expression /
- β-Galactosidase /
- Lactococcus lactis
Abstract: Objective This study is to examine the secretion effects of β-galactosidase in Lactococcus lactis.Methods The usp45 and β-galactosidase genes were cloned and inserted into plasmid pMG36e to obtain the recombinant plasmid pMG36e-usp-lacZ.This recombinant plasmid was transformed into both Escherichia coli DH5α and L.lactis MG1363.The enzyme activity,gene sequencing,SDS-PAGE and hereditary stability were assessed and studied.Results The lacZ gene inserted into plasmids pMG36e-usp-lacZ was 99.37％ similar to the GenBank sequence,and SDS-PAGE revealed an evident idio-strap at 116 KDa between L.lactis MG1363/pMG36eusp-lacZ in both supernatant and cell samples.β-Galactosidase activity measured 0.225 U/mL in L.lactis pMG36e-usp-lacZ transformants,and its secretion rate was 10％.The plasmid pMG36e-usp-lacZ appeared more stable in MG1363.Conclusion The authors concluded that these new recombinant bacteria well expressed and secreted β-galactosidase,indicating that the β-galactosidase expression system was successfully constructed,and this might provide a new solution for management of lactose intolerance specifically and promote the use of gene-modified organisms as part of the food-grade plasmid in general.
|Citation:||ZHANG Wen, WANG Chuan, HUANG Cheng Yu, YU Qian, LIU Heng Chuan, ZHANG Chap Wu, PEI Xiao Fang. Construction and Secretory Expression of β-Galactosidase Gene from Lactobacillus Bulgaricus in Lactococcus Lactis[J]. Biomedical and Environmental Sciences, 2012, 25(2): 203-209. doi: 10.3967/0895-3988.2012.02.012|