Production of recombinant proteins in the lon-deficient BL21(DE3) strain of Escherichia coli in the absence of the DnaK chaperone.
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ABSTRACT:
SUBMITTER: Ratelade J
PROVIDER: S-EPMC2687262 | biostudies-literature | 2009 Jun
REPOSITORIES: biostudies-literature
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Production of recombinant proteins in the lon-deficient BL21(DE3) strain of Escherichia coli in the absence of the DnaK chaperone.
Ratelade Julien J Miot Marie-Caroline MC Johnson Emmett E Betton Jean-Michel JM Mazodier Philippe P Benaroudj Nadia N
Applied and environmental microbiology 20090403 11
To eliminate unavoidable contamination of purified recombinant proteins by DnaK, we present a unique approach employing a BL21(DE3) DeltadnaK strain of Escherichia coli. Selected representative purified proteins remained soluble, correctly assembled, and active. This finding establishes DnaK dispensability for protein production in BL21(DE3), which is void of Lon protease, key to eliminating unfolded proteins. ...[more]
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