Best Grams Of Proteins

Cited in over 350 research articles, Lucigen's OverExpress C41(DE3) and C43(DE3) Competent Cells are highly effective in expressing toxic and membrane proteins. With these BL21(DE3) derivatives, you can efficiently and reliably express genes cloned into any T7 vector. E. coli BL21(DE3) strains, like Lucigen's E. cloni EXPRESS Competent Cells, provide reliable expression of many genes cloned into T7 expression vectors (e.g., pET or Lucigen's Expresso T7 vectors). However, in some cases expression is minimal or undetectable because the recombinant protein, when expressed, is deleterious or lethal to these standard BL21 strains. Examples of such toxic proteins include many membrane proteins, some cytoplasmic proteins, and nucleases. Unfortunately, successful expression of one or more toxic proteins is often very important to the experimental goal. Lucigen's OverExpress Electrocompetent and Chemically Competent Cells are E. coli strains that are effective in expressing toxic proteins from all classes of organisms. These include toxic proteins from eubacteria, yeasts, plants, viruses, and mammals. The OverExpress strains contain genetic mutations phenotypically selected for conferring tolerance to toxic proteins. The strain C41(DE3) was derived from BL21(DE3). This strain has at least one mutation, which prevents cell death associated with expression of many recombinant toxic proteins. The strain C43(DE3) was derived from C41(DE3) by selecting for resistance to a different toxic protein and can express a different set of toxic proteins to C41(DE3). As in standard BL21(DE3) strains, OverExpress C41(DE3), C41(DE3)pLysS, C43(DE3), and C43 (DE3)pLysS are lysogens of lambdaDE3. These strains carry a chromosomal copy of the T7 RNA Polymerase gene under the control of the lacUV5 promoter. These strains are suitable for production of protein from target genes cloned into T7-driven expression vectors. OverExpress C41(DE3), C41(DE3) pLysS, C43(DE3), and C43(DE3) pLysS are also de