
- Best value for routine protein expression… available as Electrocompetent and Chemically Competent Cells.
Name | SKU | Size | Availability | Vendor | Price | Order | |
E. cloni® EXPRESS BL21(DE3) Electrocompetent Cells, 12 rxns |
60300-1 | 12 Rxns | Generally 1-2 weeks from receipt of order | LGC Biosearch Technologies - Lucigen (Epicentre) | Log in for pricing | ||
E. cloni® EXPRESS BL21(DE3) Electrocompetent Cells, 24 rxns |
60300-2 | 24 Rxns | Generally 1-2 weeks from receipt of order | LGC Biosearch Technologies - Lucigen (Epicentre) | Log in for pricing |
Lucigen’s E. cloni EXPRESS BL21(DE3) Electrocompetent Cells are the first to offer high efficiency cloning and high level protein expression in the same cell. Cloning efficiencies are increased 25-1,000 fold relative to competitors’ preparations of BL21 cells (Figure 1), which is essential for construction of complex expression libraries. The unprecedented transformation efficiency of E. cloni EXPRESS Electrocompetent Cells (> 5 × 109 cfu/µg) eliminates the need for plasmid transfer from the cloning strain to the expression strain, saving days of work in a typical cloning and expression experiment (Figure 2).
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Figure 1. Transformation efficiency comparison of commercially available BL21(DE3) competent cells.
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Figure 2. Comparison of cloning and protein expression procedures. |
E. cloni EXPRESS BL21(DE3) strains contain the phage T7 RNA polymerase gene linked to the IPTG-inducible promoter, for use with any expression plasmid containing the T7 promoter.
NOTE: For best results in expressing proteins that may be toxic, we recommend using OverExpress Cells. E. cloni EXPRESS cells are also available as chemically competent cells. With a transformation efficiency of >1 × 107 cfu/µg and very economical prices, EXPRESS Chemically Competent Cells offer superior value for everyday protein expression work.