Use of a derivative of Escherichia coli BL21(DE3) for efficient production of three different recombinant proteins.
Plasmid instability and growth inhibition of plasmid-bearing cells after induction were encountered when E. coli BL21(DE3) was used as host for the production of antihuman ovarian carcinoma x antihuman CD3 single-chain bispecific antibody (AhOC x AhCD3), human soluble B lymphocyte stimulator fused with thioredoxin (Trx-hsBLyS) and human parathyroid hormone fused with thioredoxin (Trx-hPTH). A derivative of BL21(DE3), namely, BLRM(DE3), isolated and showing superiority in AhOC x AhCD3 production in our previous work, was further used here for more efficient production of these three different recombinant proteins. By using BLRM(DE3) as host, the simplified one-stage fermentation process was developed, which was more labor-saving and yielded AhOC x AhCD3, comparable to that of the traditional two-stage fermentation process. Also, the plasmid stabilities and production yields of Trx-hsBLyS and Trx-hPTH were dramatically improved by the application of BLRM(DE3) instead of BL21(DE3). A high Trx-hsBLyS yield (about 3.5 g/L) was obtained, which was more than twice as much as that of the recombinant BL21(DE3) strain. The Trx-hPTH yield was improved from about 700 mg/L to 1 g/L. These results further showed the superiority of BLRM(DE3) to BL21(DE3) and suggested its effectiveness for other BL21(DE3)/pET heterologous protein expression systems, which encounter similar problems.
Zhao
Jing-Bo
JB
State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China.
Wei
Dong-Zhi
DZ
D004926:Escherichia coli / Q000145:classification* / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000096:biosynthesis* / Q000235:genetics*; D024861:Genetic Enhancement / Q000379:methods*; D015202:Protein Engineering / Q000379:methods*; D011994:Recombinant Proteins / Q000096:biosynthesis*; D013045:Species Specificity
D029968:Escherichia coli Proteins; D011994:Recombinant Proteins