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70625 Tuner™(DE3)pLacI Competent Cells - Novagen

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Replacement Information


Catalogue NumberPackaging Qty/Pack
70625-3 Plastic ampoule 0.4 ml
70625-4 Glass bottle 1 ml
OverviewExpression host strains for pETBlue™ and pTriEx™ vectors are lDE3 lysogens that also carry the compatible pLacI plasmid, encoding the lac repressor. The pLacI plasmid confers chloramphenicol resistance and provides enough lac repressor to inhibit transcription from the T7lac promoter in the absence of inducer. The NovaBlue host strain is recommended for initial cloning with pETBlue and pTriEx vectors due to its superior transformation efficiency and high yields of high-quality plasmid DNA.

Note that these strains are not recommended for use with pET, pACYCDuet™, pCDF, pRSF, pCOLADuet™ or pETcoco™ vectors.

.Tuner™ strains are lacZY deletion mutants of BL21 and enable adjustable levels of protein expression throughout all cells in a culture. The lac permease (lacY) mutation allows uniform entry of IPTG into all cells in the population, which produces a concentration-dependent, homogeneous level of induction. By adjusting the concentration of IPTG, expression can be regulated from very low levels up to the robust, fully induced levels commonly associated with pET vectors. Lower-level expression may enhance the solubility and activity of difficult target proteins. In Tuner(DE3)pLacI, the rare tRNA genes are present on the same plasmid that carries the lac repressor gene.

DE3 indicates that the host is a lysogen of λDE3, and therefore carries a chromosomal copy of the T7 RNA polymerase gene under control of the lacUV5 promoter. Such strains are suitable for production of protein from target genes cloned in pET vectors by induction with IPTG.
Genotype: F ompT hsdSB (rB mB) gal dcm lacY1(DE3) pLacI (CamR)

This product contains genetically modified organisms (GMO). Within the EU GMOs are regulated by Directives 2001/18/EC and 2009/41/EC of the European Parliament and of the Council and their national implementation in the member States respectively. This legislation obliges MilliporeSigma to request certain information about you and the establishment where the GMOs are being handled. Click here for Enduser Declaration (EUD) Form.

This product is sold for internal research use only. Any commercial use of this product, its components, and/or any derivatives thereof (including but not limited to proteins produced using the product or its components) (together and hereinafter the 'EMD Product') requires signature of a written commercial use agreement with EMD Millipore Corporation or its successor-in-interest. Commercial use shall include but not be limited to: (1) use of the EMD Product to manufacture products for sale to third parties; (2) use of the EMD Product to provide services, information, or data to third parties in exchange for consideration; (3) use of the EMD Product for therapeutic, diagnostic or prophylactic purposes (including as part of a device, chip, assay or other product); or (4) resale of the EMD Product, whether or not such EMD Product is resold for research use. Nothing contained herein shall be deemed to represent or warrant that additional third party rights are not required for use of the EMD Product. Please direct any questions on these use restrictions to:
Catalogue Number70625
Brand Family Novagen®
Product Information
Guaranteed efficiencyGuaranteed efficiency: > 2 x 10⁶ cfu/µg
Quality LevelMQ100
Biological Information
Physicochemical Information
Materials Information
Toxicological Information
Safety Information according to GHS
Safety Information
Product Usage Statements
Storage and Shipping Information
Ship Code Dry Ice Only
Toxicity Multiple Toxicity Values, refer to MSDS
Storage ≤ -70°C
Avoid freeze/thaw Avoid freeze/thaw
Do not freeze Ok to freeze
Packaging Information
Transport Information
Supplemental Information
Global Trade Item Number
Catalogue Number GTIN
70625-3 04055977257533
70625-4 04055977257540


Tuner™(DE3)pLacI Competent Cells - Novagen SDS


Safety Data Sheet (SDS) 

Tuner™(DE3)pLacI Competent Cells - Novagen Certificates of Analysis

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  • User Protocols

    TB009 Competent Cells
    TB053 Academic and Non-profit Laboratory Assurance Letter
    TB249 pETBlue™ System Manual
    TB250 pTriEx™ System Manual