NEB® 5-alpha Competent E. coli (Subcloning Efficiency)


Catalog # Size Price (£)
C2988J 6 X 0.4 ML £68.00

NEB 5-alpha Competent E. coli is a derivative of the popular DH5α. It is T1 phage resistant and endA deficient for high-quality plasmid preparations. 

  • Ideal for subcloning efficiency transformations, such as plasmid transformation or routine subcloning
  • No dry ice surcharge on competent cell shipments
  • Free of animal products
  • High efficiency chemical and electrocompetent formats are also available

Chemically competent E. coli cells suitable for subcloning efficiency transformations, such as plasmid transformation or routine subcloning (e.g,. inserting a 1 kb fragment into a 2 kb vector). The efficiency of these cells is not sufficiently high for most other cloning applications. For that, we recommend NEB® 5-alpha Competent E. coli (High Efficiency) (NEB #C2987) which has 1,000-fold higher transformation efficiency.


  • Activity of nonspecific endonuclease I (endA1) eliminated for highest quality plasmid preparations

  • Transformation efficiency > 1 x 106 cfu/µg pUC19 DNA

  • Efficient transformation of unmethylated DNA derived from PCR, cDNA and many other sources (hsdR)

  • Reduced recombination of cloned DNA (recA1)

  • Resistance to phage T1 (fhuA2)

  • Suitable for blue/white screening by α-complementation of the β-galactosidase gene

  • K12 Strain

  • DH5α™ derivative

  • Free of animal products


fhuA2 Δ(argF-lacZ)U169 phoA glnV44 Φ80Δ (lacZ)M15 gyrA96 recA1 relA1 endA1 thi-1 hsdR17

Reagents Supplied

The following reagents are supplied with this product:


Component Name

Component #

Stored at (°C)



  • C2988J






Advantages and Features

Properties & Usage

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Quality Control Assays

Certificate of Analysis

Specifications & Change Notifications

The Specification sheet is a document that includes the storage temperature, shelf life and the specifications designated for the product. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]

The following link is to a PDF Safety Data Sheet (SDS) that applies to this product to help you use it safely.


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