Invitrogen™ One Shot™ BL21(DE3)pLysE Chemically CompetentE. coli

Description

• One Shot BL21(DE3)pLysE Chemically Competent E
• coli cells are ideal for use with bacteriophage T7 promoter-based expression systems such as pRSET and pET
• The pLysE plasmid carried by the BL21(DE3)pLysE strain produces higher amounts of T7 lysozyme than pLysS to further reduce basal level expression of the gene of interest
• Like pLysS, pLysE confers resistance to chloramphenicol (CamR) and contains the p15A origin for compatibility with plasmids containing the ColE1 or pMB1 origin (i.e
• pUC- or pBR322- derived plasmids)
• Recombinant proteins that are nontoxic to E
• coli are generally expressed at higher levels in BL21(DE3) cells as compared to the BL21(DE3)pLysE strain with tighter expression control
• The BL21(DE3)pLysE strain is recommended for use when expressing toxic genes (alternatively, BL21-AI could be considered)
• The BL21 (DE3) E
• coli strain is one of the most popular host strains to produce recombinant proteins and adapted in research or industrial applications (e.g., first biopharmaceutical recombinant human insulin)
• This strain had been engineered to carry the λDE3 lysogen that contains the T7 RNA polymerase gene under control of the lac UV5 promoter
• IPTG is required to induce expression of the T7 RNA polymerase cascade system that in turn transcribe the T7 promoter regulated target gene
• BL21(DE3) is a derivative of the E
• coli B strain that does not contain the lon protease and is also deficient in the outer membrane protease OmpT
• The lack of two key proteases reduces degradation of heterologous proteins expressed in the strains
• Additionally, several other strain features make them especially suited for protein production, namely fast growth in minimal medium, a lower acetate production when grown in high glucose media, and the ability to reach high cell density
• One Shot BL21(DE3)pLysE Chemically Competent E
• coli offer: • Transformation efficiency of >1 x 10 7 cfu/μg control plasmid DNA • Ion and OmpT protease deficiency reduces degradation of recombinant protein • IPTG-inducible lac UV5 promoter controls expression of the T7 RNA polymerase • pLysE (CamR) plasmid for reduced basal expression in uninduced cells • hsd S mutation allows efficient transformation of unmethylated DNA • Fast growth in minimal medium and ability to reach high cell density BL21(DE3)pLysE E
• coli are ideal for use with T7 promoter-based expression vectors
• Like BL21(DE3)pLysS E
• coli , BL21(DE3)pLysE cells carry the lambda DE3 lysogen
• In addition, BL21(DE3)pLysE cells contain the pLysE plasmid, which constitutively expresses T7 lysozyme
• T7 lysozyme reduces the basal expression of target genes by inhibiting T7 RNA polymerase
• The pLysE plasmid in BL21(DE3)pLysE expresses higher levels of T7 lysozyme than the pLysS plasmid in BL21(DE3)pLysS
• The BL21(DE3)pLysE strain provides tighter control of T7 RNA polymerase, which is necessary when the recombinant protein to be expressed is toxic
• Easy-to-use One Shot format BL21(DE3)pLysE Chemically Competent E
• coli cells are supplied in the convenient, single-reaction One Shot format
• The single-tube, single-use format allows all steps of the transformation protocol, up to plating, to take place in the same tube, thereby helping save time and prevent contamination
• Genotype F – omp T hsd SB (r B –, m B –) gal dcm (DE3) pLysE(CamR) Find the strain and format that you need • We offer other E
• coli strains for protein expression
• • For expression of toxic proteins, consider BL21-AI One Shot Chemically Competent E
• coli (Cat
• No
• C607003)
• • BL21 Star (DE3) and other strains are available in MultiShot formats for high throughput applications
• • We offer a variety of systems for the expression of recombinant proteins in E
• coli , the Champion pET expression system provides the highest level of protein production available in any expression system.