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69042 B834(DE3)pLysS Competent Cells - Novagen

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Catalog NumberPackaging Qty/Pack
69042-3 Plastic ampoule 0.4 ml
69042-4 Glass bottle 1 ml
OverviewB834 is the parental strain for BL21 (1). These protease-deficient hosts are methionine auxotrophs and allow high specific-activity labeling of target proteins with 35S-methionine and selenomethionine for crystallography (2).

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.

pLysS strains express T7 lysozyme, which further suppresses basal expression of T7 RNA polymerase prior to induction, thus stabilizing pET recombinants encoding target proteins that affect cell growth and viability.

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:
Genotype: F- ompT hsdSB(rB- mB-) gal dcm met (DE3) pLysS (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.
Catalogue Number69042
Brand Family Novagen®
Features and benefits• Allows for ³⁵S-methionine or selenomethionine labeling for crystallography studies
• Deficient in Ion and ompT proteases
• Guaranteed transformation efficiencies of >2x10⁶ cfu/µg
• Provided in a 0.2 ml volume; each vial can be used for 10 x 20 µL transformations
• Prepared using an optimized chemical method
References1. Wood, W. B. (1966) J. Mol. Biol. 16, 118–133.

2. Leahy, D. J., Hendrickson, W. A., Aukhil, I., and Erickson, H. P. (1992) Science 258, 987–991.
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
Catalog Number GTIN
69042-3 04055977259735
69042-4 04055977259742


B834(DE3)pLysS Competent Cells - Novagen SDS


Safety Data Sheet (SDS) 

B834(DE3)pLysS Competent Cells - Novagen Certificates of Analysis

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Reference overview
1. Wood, W. B. (1966) J. Mol. Biol. 16, 118–133.

2. Leahy, D. J., Hendrickson, W. A., Aukhil, I., and Erickson, H. P. (1992) Science 258, 987–991.


Express yourself


  • Eric T. Larson, et al. (2006) Structure of A197 from Sulfolobus turreted icosahedral virus: a crenarchaeal viral glycosyltransferase exhibiting the GT-A Fold. Journal of Virology 80, 7636-7644.
  • Marcin Nowotny, et al. (2005) Crystal structures of RNase H bound to an RNA/DNA hybrid: substrate specificity and metal-dependent catalysis. Cell 121, 1005-1016.
  • J. Bayrer, et al. (2004) Expression, crystallization and preliminary X-ray characterization of the Drosophila transcription factor Doublesex. Acta Crystallographica D60, 1328-1330.
  • Meindert H. Lamers, et al. (2000) The crystal structure of a DNA mismatch repair protein MutS binding to a GT mismatch. 407, 711-717.
  • T..M.T. Hall, et al. (1997) Crystal structure of a hedgehog autoprocessing domain: homology between hedgehog and self-splicing proteins. Cell 91, 85-97.
  • User Protocols

    TB009 Competent Cells
    TB053 Academic and Non-profit Laboratory Assurance Letter