BL21 Competent Cells, Uni-pack 

Sigma's BL21-T1^R competent E. coli cells are grown and made chemically competent using an optimized procedure specific to the strain, followed by strain verification and efficiency testing. The cells are provided in frozen 50 μl aliquots for convenience. Each aliquot can be used for a single transformation.

BL21-T1^R competent Escherichia coli is an all-purpose expression strain suitable for the high level production of heterologous proteins directed by various expression vector systems (promoters such as lac, trc, tac, λPL, and araD). BL21-T1^R is a B/r strain bacteria, which naturally lacks the lon protease and is also deficient in the outer membrane protease ompT. The absence of proteolytic activity from these two proteases may reduce degradation of some heterologous proteins expressed in the strain. In addition, the tonA genotype confers resistance to the lytic bacteriophages T1 and T5 for protection of clonal stocks.

dry ice

−70°C

S1797, SOC Medium

L7533, LB Agar EZMix^™ Powder

pUC19 Control DNA

BL21-T1^R Competent Cells