[Gene cloning and overexpression of dichloromethane dehalogenase from Bacillus circulans WZ-12].
The dcmR gene encoding dichloromethane dehalogenase was amplified by PCR from Bacillus circulans WZ-12 and cloned to expression vector pET28b(+), yielding recombinant plasmid pET28b(+)-dcmR. Then plasmid pET28b(+)-dcmR was introduced into Escherichia. coli BL21(DE3). Expression was induced by IPTG,and the enzyme activity reached 25.78 U/mL, the specific enzyme activity reached 88.86 U/mg protein.The periplasmic and cytoplasmic enzyme activity reached 2.92 U/mL and 22.86 U/mL respectively.All results analysis demonstrated that the E. coli. strain carrying the dcmR gene could produce dichloromethane dehalogenase efficiently. The growth characteristics of dcmR-1 was compared with the original strain, and the result showed that there was no difference, A(600nm) of dcmR-1 in LB medium could reach about 2.4 in logarithmic period,which was the same as that of the original strain. The recombinant strain dcmR-1 showed the higher degrading ability than Bacillus circulans WZ-12 and with more than 90% removal efficiency of 120 mmol/L CH2Cl2 in 25 h. All these results indicated that recombinant strain dcmR-1 was a promising strain in bioremediation of CH2Cl2 contaminated environment.
Wu
Shi-jin
SJ
College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China. wujan28@zjut.edu.cn
Zhang
Hua-xing
HX
Hu
Zhi-hang
ZH
Chen
Jian-meng
JM
D001407:Bacillus / Q000201:enzymology* / Q000235:genetics*; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D008190:Lyases / Q000096:biosynthesis* / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics
D001426:Bacterial Proteins; D011994:Recombinant Proteins; D008190:Lyases; C045224:dichloromethane dehalogenase