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CMC0024

Sigma-Aldrich

CONTROLLER BL21(DE3) Chemically Competent Cells

Escherichia coli, rod shaped

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About This Item

UNSPSC Code:
12352200
NACRES:
NA.85

product name

CONTROLLER BL21(DE3) Chemically Competent Cells, for controlled protein expression

biological source

Escherichia coli

grade

for molecular biology

growth mode

adherent or suspension

morphology

rod shaped

technique(s)

microbiological culture: suitable

cell transformation

competent cell type: chemically competent
transformation efficiency: >1 x 107 cfu/μg

shipped in

dry ice

storage temp.

−70°C

General description

The CONTROLLER BL21(DE3) Chemically Competent Cells are an E. coli strain optimized for high efficiency transformation.
They are ideal for cloning and propagation of plasmid clones. They give high yield and high quality plasmid DNA.
Genotype

F- ompT hsdSB (rB- mB-) gal dcm (DE3) Mini-F lacIq1(GentR)

Features and Benefits

  • Reduce leaky expression: The LacI repressor protein binds to the lacO operator to block transcription of downstream genes. In the absence of an induction agent such as lactose sugar or IPTG, target protein expression from the adjacent promoter will be greatly reduced.
  • High protein yields: Both 10G and BL21(DE3)-based strains are noted for their ability to express high levels of protein. For expression from a T7 promoter please select the HI-Control BL21(DE3) strain. This strain also is deficient in proteases, yielding more stable protein preparations. Most other promoters can be used in either HI-Control strain.
  • Terrific efficiency: The simple, reliable heat-shock procedure for chemical transformation gives excellent results from small amounts of plasmid DNA.

Components

  • CONTROLLER BL21(DE3) chemically competent cells
  • pUC 19 transformation control DNA
  • recovery medium for expression


Storage Class Code

10 - Combustible liquids


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