Library Efficiency™ DH5α Competent Cells

Library Efficiency DH5α Competent Cells are a versatile strain of chemically competent cells that are used in many everyday cloning applications. Prepared by a proprietary modification of the Hanahan method, these cells are able to achieve transformation efficiencies of >1 x 10⁸ cfu/μg control DNA per 100 μL reaction.  
 
Library Efficiency DH5α Competent Cells are recommended for routine cloning of genes into large plasmids and are suitable for difficult clone constructions, such as blunt-end ligations or cloning using limited amount of DNA.

The strain has the lacZΔM15 genotype, allowing blue-white screening on plates containing either X-Gal or Bluo-Gal. It also carries the recA1 mutation, which helps reduce the rate of recombination while propagating plasmid DNA, and the endA1 mutation that makes DH5α cells an excellent choice for amplifying plasmid DNA for subsequent extraction and purification. DH5α cells are capable of being transformed efficiently with large plasmids and can serve as a host for the M13mp cloning vectors if a lawn of DH5αF′IQ, for example, is provided to allow plaque formation.

Library Efficiency DH5α Competent Cells offer: 
• Transformation efficiencies of >1 x 10⁸ cfu/μg
• lacZΔM15 marker that provides α-complementation of the β-galactosidase gene allowing blue/white screening on agar plates containing X-Gal or Bluo-Gal
• Plasmid DNA maintained with minimum recombination events due to recA1 mutation
• endA1 mutation that enables increased plasmid yield and quantity
• hsdR17 genotype that allows efficient transformation of cloned unmethylated DNA from PCR

Genotype
F^- Φ80lacZΔM15 Δ(lacZYA-argF) U169 recA1 endA1 hsdR17 (rk-, mk+) phoA supE44 λ-thi-1 gyrA96 relA1

Find the strain and format that fits your needs 
DH5α strain and its derivatives are available with a variety of transformation efficiencies and in both electrocompetent and chemically competent formats.
MAX Efficiency DH5αF´IQ Competent Cells are available in chemically competent format.
DH5α-T1R competent cells are available in MultiShot format for high throughput applications.
Explore bacterial growth media formats.