摘要
为了增加高热稳定性的葡萄糖异构酶的得率,采用PCR技术扩增得到Thermus thermophilusHB8葡萄糖异构酶基因xylA,连接到表达载体pET-22b(+)上,获得重组质粒pET-22b(+)-xylA。将重组质粒转化到大肠杆菌Rosetta(DE3)中,经IPTG诱导后,通过半胱氨酸-咔唑法测葡萄糖异构酶酶活。重组菌经诱导培养,SDS-PAGE电泳结果显示出明显的分子量约为44 kD特异性蛋白质条带,比酶活约为18.562 U/mg,比野生型菌株提高了2倍。
In order to gain the productivity of glucose isomerase with high thermostability, xylA gene were successfully amplified by PCR reaction from Thermus thermophilus HB8 and were ligated to expression vector pET-22b（ ＋ ）. E. coli Rosetta（DE3） competent cells were transformed with the recombinant plasmid pET-22b （ ＋ ）-xylA. The glucose isomerase activity of recombinant strain was determined after IPTO induction by modified Cysteine-carbazole assay. The special protein band about 44 kD was shown in the SDS-PAGE gel. The glucose isomerase activity of recombinant strain was 18.562 U/mg under optimal conditions and 3 times as much as that of wild-type strain.
出处
《生物加工过程》
CAS
CSCD
2006年第2期42-45,共4页
Chinese Journal of Bioprocess Engineering
基金
国家973项目(2003CB716000)
