One Shot® Stbl3™ Chemically Competent E. coli are designed especially for cloning direct repeats found in lentiviral expression vectors. Unlike TOP10 E. coli, these cells reduce the frequency of homologous recombination of long terminal repeats (LTRs) found in ViraPower™ Lentiviral Expression Vectors and other retroviral vectors. The DNA yield from Stbl3™ cells is often >10-fold higher than alternative strains such as TOP10 (see table). One Shot® Stbl3™ Chemically Competent Cells deliver:

• Optimal performance for the propagation of lentiviral vectors
• Enhanced genomic cloning capacity (mcrB, mrr)
• Expected efficiency of >1 × 10⁸ transformants/µg plasmid DNA
• High DNA yields

Recommended use
The Stbl3™ E. coli strain is derived from the HB101 E. coli strain and is recommended for use when cloning unstable inserts such as lentiviral DNA containing direct repeats (e.g., Invitrogen® ViraPower™ Lentiviral Expression kits). The transformation efficiency of One Shot® Stbl3™ chemically competent cells is greater than 1 × 10⁸ cfu/µg plasmid DNA.

Genotype: F^-mcrB mrrhsdS20(r_B^-, m_B^-) recA13 supE44 ara-14 galK2 lacY1 proA2 rpsL20(Str^R) xyl-5 λ^-leumtl-1

Find the strain and format that you need
We offer a variety of competent cells for the propagation of unstable DNA inserts.

• MAX Efficiency® Stbl2™ Competent Cells—stable cloning of direct repeat and retroviral sequences and tandem array genes (5 × 200 µL) (>1 × 10⁹ cfu/µg plasmid DNA)
• One Shot® Stbl3™ Chemically Competent E. coli—cloning unstable inserts containing direct repeats (20 × 50 µL) (>1 × 10⁸ cfu/µg plasmid DNA)
• ElectroMAX™ Stbl4™ Competent Cells—high transformation efficiencies (>5 × 10⁹ cfu/µg plasmid DNA), ideal for generating cDNA and genomic libraries and for cloning unstable inserts