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This content will become publicly available on July 17, 2019

Title: T7 Expression Systems for Inducible Production of Proteins from Cloned Genes in E. coli

Inducible T7 expression systems are capable of producing a wide range of proteins in E. coli. Improvements over common practice include: preventing unintended induction by establishing and maintaining expression strains in non-inducing growth media comprised entirely of purified components instead of complex growth media that may variably induce target proteins on approach to saturation; and expressing many target proteins in parallel by convenient and productive auto-induction in BL21(DE3) and other suitable hosts, instead of IPTG induction. From earliest days, basal expression prevented establishment of inducible strains for producing proteins that are stressful to the host. Newly developed pAL vectors now reduce basal expression to levels where coding sequences for even the most stressful proteins can be maintained and induced. In conclusion, asymmetric ligation allows simple and efficient cloning of individual coding sequences or simultaneous cloning of two or three coding sequences for co expression from a single pAL vector.
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1934-3639
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Current Protocols in Molecular Biology
Additional Journal Information:
Journal Name: Current Protocols in Molecular Biology; Journal ID: ISSN 1934-3639
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Country of Publication:
United States
59 BASIC BIOLOGICAL SCIENCES; BL21(DE3); BL21-AI; MDAG non-inducing growth media; asymmetric ligation; auto-induction; basal expression; co-expression; pAL vectors
OSTI Identifier: