These competent cells are optimized for protein expression from T7 promoters. All are induced with IPTG or L-arabinose and come in the convenient One Shot format, allowing for transformation and recovery in a single tube.

Which competent cell strain is right for you?

 High-level expression of recombinant proteinsHighest protein expression from low-copy plasmidsHighest protein expression from high-copy plasmidsOptimized or ideal for toxic proteins
Increased mRNA stability (mutated rne gene)    
Expression of known toxic genes    
Top Seller    
Best expression vector formatpET-based expression vector (low copy number T7-based plasmids)pET-based expression vector (low copy number T7-based plasmids)pCR T7-based expression vector (high copy number, T7-based plasmids)ANY
T7-based expression vector
Inducing agentIPTGIPTGIPTGArabinose or Arabinose & IPTG
One Shot formatOne ShotOne ShotOne ShotOne Shot
Kit contains20 tubes x 50 µL20 tubes x 50 µL20 tubes x 50 µL20 tubes x 50 µL
*BL21 Star (DE3) E. coli strain also available as higher throughput StripWell Format