10 replies to this topic

[minemin]

Hi everyone,

I'm using E coli DH5a for my transformations, and I was wondering what the DH5alpha stands for.
Is there anyone who can help me?
Thank you

[bob1]

It is  a strain name, much as E. coli O15H is a famous pathogenic strain.

[minemin]

bob1, on Apr 26 2009, 05:49 PM, said:

It is  a strain name, much as E. coli O15H is a famous pathogenic strain.

I know it's a strain name, but I was interested if the D H 5a has some meaning. Some special features or something

[HomeBrew]

The original reference is: Bethesda Research Laboratories. 1986. BRL pUC host: E. coli DH5α competent cells. Focus 8(2):9. (see here).  DH5α was derived from E. coli DH5, described in Hanahan, D. 1985. in DNA Cloning: A Practical Approach. Glover, D. M. (ed.), Vol. 1, p. 109, IRL Press, McLean, Virginia.  "DH" are the initials of Doug Hanahan.

[swanny]

HomeBrew, on Apr 28 2009, 06:27 AM, said:

The original reference is: Bethesda Research Laboratories. 1986. BRL pUC host: E. coli DH5α competent cells. Focus 8(2):9. (see here).  DH5α was derived from E. coli DH5, described in Hanahan, D. 1985. in DNA Cloning: A Practical Approach. Glover, D. M. (ed.), Vol. 1, p. 109, IRL Press, McLean, Virginia.  "DH" are the initials of Doug Hanahan.

Nice to be remembered for posterity by having a strain of bug named after you! Like good ole Dr Escherich! Could be worse, I suppose: you might have some horrible skin condition with your name on it!!!

[cheerioet]

HomeBrew, on Apr 28 2009, 04:27 AM, said:

The original reference is: Bethesda Research Laboratories. 1986. BRL pUC host: E. coli DH5α competent cells. Focus 8(2):9. (see here).  DH5α was derived from E. coli DH5, described in Hanahan, D. 1985. in DNA Cloning: A Practical Approach. Glover, D. M. (ed.), Vol. 1, p. 109, IRL Press, McLean, Virginia.  "DH" are the initials of Doug Hanahan.

Wow...Now I know DH5alpha is named from someone initials. Thanks.

[hanming86]

Nice one Homebrew. I really appreciate that knowledge . D. Hanathan 5 ~~  this guy drives fast car and work late in the night mysteriously if i m not mistaken as written in Sambrook .

[HomeBrew]

And all those highly competent E. coli cells you buy or make?  He worked that out in D Hanahan. 1983. Studies on transformation of Escherichia coli with plasmids. J Mol Biol 166(4):557-580, which, by the way, is also from where we get SOB and SOC media.

[Ratna]

Hi Everyone!

It was interesting to read all your answers  

What could be its pathogenicity levels of this bacteria, is it  BSL-2 pathogen? I was building a risk assessment form for this strain and came up with these questions.

Thank you

[phage434]

DH5a and other common K-12 E. coli derivatives used in the lab are BSL-1, and non-pathogenic to normal healthy individuals.  You should still use good lab practices in handling all bacterial samples, including autoclaving contaminated waste, bleaching discarded liquid cultures, and washing your hands.

[Ratna]

Thank you for your reply.

I have to attach the msds of the strain alongwith the form. I could not find the exact one on the internet.

Can you help me please?