Tunable expression rate control of a growth-decoupled T7 expression system by l-arabinose only

Microbial Cell Factories

Gerald Striedner¹  Patrick Stargardt²  Juergen Mairhofer² 

[1] Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190, Vienna, Austria;enGenes Biotech GmbH, Mooslackengasse 17, 1190, Vienna, Austria;

关键词: Escherichia coli;    enGenes-X-press;    Growth-decoupled;    gp2;    BL21-AI;    Recombinant protein production;    Expression rate control;    Resource reallocation;    Flow cytometry;    pBAD;    -Arabinose;   

DOI  :  10.1186/s12934-021-01512-7

来源: Springer

【 摘 要 】

BackgroundPrecise regulation of gene expression is of utmost importance for the production of complex membrane proteins (MP), enzymes or other proteins toxic to the host cell. In this article we show that genes under control of a normally Isopropyl β-d-1-thiogalactopyranoside (IPTG)-inducible PT7-lacO promoter can be induced solely with l-arabinose in a newly constructed Escherichia coli expression host BL21-AI, a strain based on the recently published approach of bacteriophage inspired growth-decoupled recombinant protein production.ResultsHere, we show that BL21-AI is able to precisely regulate protein production rates on a cellular level in an l-arabinose concentration-dependent manner and simultaneously allows for reallocation of metabolic resources due to l-arabinose induced growth decoupling by the phage derived inhibitor peptide Gp2. We have successfully characterized the system under relevant fed-batch like conditions in microscale cultivation (800 µL) and generated data proofing a relevant increase in specific yields for 6 different Escherichia coli derived MP-GFP fusion proteins by using online-GFP signals, FACS analysis, SDS-PAGE and western blotting.ConclusionsIn all cases tested, BL21-AI outperformed the parental strain BL21-AI, operated in growth-associated production mode. Specific MP-GFP fusion proteins yields have been improved up to 2.7-fold. Therefore, this approach allows for fine tuning of MP production or expression of multi-enzyme pathways where e.g. particular stoichiometries have to be met to optimize product flux.

【 授权许可】

CC BY