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71397 Rosetta™ 2(DE3) Competent Cells - Novagen

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Catalog NumberPackaging Qty/Pack
71397-3 Plastic ampoule 0.4 ml
71397-4 Glass bottle 1 ml
OverviewA common method for transformation of DNA plasmids into E. coli is the use of chemically competent cells. Although competent cells can be prepared in the laboratory, greater efficiency, reproducibility, and convenience are achieved using Novagen prepared competent cells. Novagen competent cells represent the widest selection available for protein expression. Every Novagen competent cell strain is verified for phenotype and purity, and is guaranteed for transformation efficiency. T7 expression strains are lysogens of bacteriophage DE3, as indicated by the (DE3). These hosts carry 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 appropriate T7 expression vectors, using IPTG as an inducer.
Rosetta™ 2 host strains are BL21 derivatives designed to enhance the expression of eukaryotic proteins that contain codons rarely used in E. coli. These strains supply tRNAs for 7 rare codones (AGA, AGG, AUA, CUA, GGA, CCC, and CGG) on a compatible chloramphenicol-resistant plasmid. The tRNA genes are driven by their native promoters.

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 (DE3) pRARE2 (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 Number71397
Brand Family Novagen®
Product Information
2 × 200 µl or 5 × 200 µl Rosetta 2(DE3) Competent Cells
2 × 2 ml or 4 × 2 mlSOC Medium
10 µlTest Plasmid
Guaranteed efficiency>2 × 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
Do not freeze Ok to freeze
Packaging Information
Transport Information
Supplemental Information
Global Trade Item Number
Catalog Number GTIN
71397-3 04055977270587
71397-4 04055977270594


Rosetta™ 2(DE3) Competent Cells - Novagen SDS


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  • Shawn S. Nelson, et al. (2007) Flavobacterium johnsoniae SprA is a cell-surface protein involved in gliding motility. Journal of Bacteriology 189, 7145-7150.
  • Trine Nilsen, et al. (2007) A nuclear export sequence located on a β-strand in fibroblast growth factor-1. Journal of Biological Chemistry 282, 26245-26256.
  • Vincent J. Starai, Youngsoo Jun and William Wickner. (2007) Excess vacuolar SNAREs drive lysis and Rab bypass fusion. Procedings of the National Academy of Science 104, 13551-13558.
  • Zahaed Evangelista-Martínez, Gabriela González-Cerón and Luis Servín-González. (2006) A Conserved Inverted Repeat, the LipR Box, Mediates Transcriptional Activation of the Streptomyces exfoliatus Lipase Gene by LipR, a Member of the STAND Class of P-Loop Nucleoside Triphosphatases. Journal of Bacteriology 188, 7082-7089.
  • Li Ge and Stephen Y. K. Seah. (2006) Heterologous expression, purification, and characterization of an L-ornithine N5-hydroxylase involved in pyoverdine siderophore biosynthesis in Pseudomonas aeruginosa. Journal of Bacteriology 188, 7205-7210.
  • Taj Kattapuram, et al. (2005) Protein kinase CK1α regulates mRNA binding by hnRNP-C in response to physiologic levels of hydrogen peroxide. Journal of Biological Chemistry 280, 15340-15347.
  • James P. Vaughn, et al. (2005) The DEXH protein product of the DHX36 gene is the major source of tetramolecular quadruplex G4-DNA resolving activity in HeLa cell lysates. Journal of Biological Chemistry 280, 38117-38120.
  • User Protocols

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