This product contains highly efficient competent cells prepared from E. coli Rosett(DE3). The competent cells can be transformed by supercoiled plasmid DNA (pUC19) with high efficiency. This product can be used for general cloning, plasmid amplification, and transformation using ligated DNA. The convenient and efficient construction of plasmid recombinants can be done with these competent cells, which are grown and then made chemically competent via an optimized procedure before the verification of cloning efficiency and strain identity. This product also can be used for making new expression host with other genetic backgrounds. As BL21 derivatives genetically designed to improve the expression of eukaryotic genes that contain codons rarely used in E. coli, Rosett host strain strains supply tRNAs for AGG, AGA, AUA, CUA, CCC, GGA codons via a compatible chloramphenicol -resistant plasmid. As a result, the Rosett strains facilitate “universal” translation which is otherwise limited by the codon usage of E. coli. DE3 signifies that the host is a lysogen of λDE3, which has a chromosomal copy of the T7 RNA polymerase gene controlled by the lacUV5 promoter. Such strains are appropriate for the protein expression from target genes cloned in pET vectors via IPTG induction.
- Strain: Rosetta(DE3) Chemically Competent E. coli
- Genotype: F- ompT hsdSB(rB- mB-) gal dcm (DE3) pRARE (CamR)
- Amplification and purification of plasmid DNAs
- Construction of genomic DNA and cDNA libraries
- General cloning
- Transformation efficiency: ≥ 3.0 x 106 cfu/μg of pUC19