E. coli DH5a

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E. coli DH5a strain freeze dried

Strain for DNA replication when cloning plasmids in bacteria.

For creating competent cells see here:


F endA1 glnV44 thi-1 recA1 relA1 gyrA96 deoR nupG purB20 φ80dlacZΔM15 Δ(lacZYA-argF)U169, hsdR17(rKmK+), λ

  • A Hoffman-Berling 1100 strain derivative (Meselson68)
  • Promega also lists phoA
  • Thiamine, arginine auxotroph
  • Lactose nonutilizing
  • Nalidixic acid resistant
  • Recombination-deficient
  • Relaxed phenotype
  • Endonuclease A deficient
  • Constitutive deoxyribose synthesis, good for cloning large plasmids.
  • Amber suppressor UAG>CAG(Gln).
  • Slow growth in M9 medium due to purB-20
  • References:
    • FOCUS (1986) 8:2, 9.
    • Hanahan, D. (1985) in DNA Cloning: A Practical Approach (Glover, D.M., ed.), Vol. 1, p. 109, IRL Press, McLean, Virginia.
    • Grant, S.G.N. et al. (1990) Proc. Natl. Acad. Sci. USA 87: 4645-4649 PMID 2162051.
    • Meselson M. and Yuan R. (1968) Nature 217:1110 PMID 4868368.

**Perishables included in this kit have been Freeze Dried. They will be viable over a month at room temperature**


17.78 (cm)
17.78 (cm)
17.78 (cm)


  • 5
    Reliable DH5a E. coli!

    Posted by Matthew Woslum on 17th Aug 2021

    Fast delivery, great customer service, and chock full of quality viable cells! Way better than rolling the dice with eBay!

  • 5

    Posted by David Nicholls on 17th Feb 2021

    No problem bringing them back to life and inserting plasmids for my experiments.

  • 5
    easy ordering process

    Posted by melinda on 19th Oct 2020

    Fast easy ordering. They always answer any questions I have. I’ll be ordering from here again.

  • 5
    Life Finds a Way

    Posted by Unknown on 17th Jun 2020

    I had some DH5a carrying a plasmid, but after several iterations of stressing and subculturing, I was unable to drive it out. For the price, this option was a much better use of my time. Despite the product image, I wasn't expecting it to come with a backup; a pleasant surprise! Used this along with some odin ampicillin for transformations and confirmed with controls that they both work.