Promotional price valid on web orders only. Your contract pricing may differ. Interested in signing up for a dedicated account number?
Learn More

EMD Millipore Novagen™ Origami™ B (DE3) pLysS Competent Cells Available on GSA/VA Contract for Federal Government customers only.

Origami B host strain derived from a lacZY mutant of BL21 to enable precise control of expression levels using IPTG. T7 lysozyme expression suppresses basal T7 expression.

Manufacturer:  Millipore Sigma 708393

 View more versions of this product

Catalog No. 70-839-3

  Check Availability
Add to cart



Origami™ B host strains carry the same mutations in trxB and gor as the original Origami strains, except that they are derived from a lacZY mutant of BL21 to enable precise control of expression levels by adjusting the concentration of IPTG. Thus the Origami B strains combine the desirable characteristics of BL21, Tuner™, and Origami strains in one strain background. The mutations in trxB and gor are selectable on kanamycin and tetracycline, respectively; therefore, these strains cannot be used with plasmids that can only selected with kanamycin or tetracycline. These strains also include the lon and ompT deficiences of BL21, which increase protein stability. 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.
Description & Specifications


Guaranteed efficiency: >2 x 106 cfu/μg
Store at ≤-70deg.C
Provide Content Correction

We continue to work to improve your shopping experience and your feedback regarding this content is very important to us. Please use the form below to provide feedback related to the content on this product.

Product Title

By clicking Submit, you acknowledge that you may be contacted by Fisher Scientific in regards to the feedback you have provided in this form. We will not share your information for any other purposes. All contact information provided shall also be maintained in accordance with our Privacy Policy.

Cancel Submit