One Shot® BL21-AI™ E. coli are chemically competent cells designed for applications that require tight regulation and strong expression of toxic proteins from any T7 promoter-based expression systems. One Shot® BL21-AI™ Chemically Competent cells have a transformation efficiency of >1×108 cfu/ µg plasmid DNA.
• Ideal for inducing expression of toxic protein
• Gene expression is regulated by the addition of L-arabinose to culture
• Suitable for use with any T7 promoter-based plasmids
• Supplied in a convenient One Shot® format
Excellent Expression of Toxic Recombinant Proteins
One Shot® BL21-AI™ E. coli contains a chromosomal insertion of the gene encoding T7 RNA polymerase (T7RNAP) into the araB locus of the araBAD operon, placing regulation of T7 RNAP under the control of the arabinose-inducible araBAD promoter (1). Therefore, this strain is especially useful for the expression of genes that may be toxic to other BL21 strains where basal expression of T7 RNAP is leaky. The BL21-AI™ strain does not contain the Ion protease and is deficient in the outer membrane protease, OmpT. This genotype reduces degradation of heterologous proteins expressed in this strain. Finally, the yield of recombinant protein obtained from BL21-AI™ is generally similar to that obtained from other BL21 strains.
Genotype:
F-ompT hsdSB (rB- mB-) gal dcm araB::T7RNAP-tetA
Easy-to-use, Single Tube Format
The single tube, single use, format allows for all transformation steps to take place in the same tube, thereby helping to save time and prevent contamination.