Inoue Competent Cell procedure

Ned Mantei mantei at neuro.biol.ethz.ch
Fri Mar 15 01:24:29 EST 1996


In article <4ia7ur$eq3 at gazette.omnilink.net>,
Christian.Moews at darmstadt.netsurf.de (Christian Moews) wrote:

> friedmrd at dunx1.ocs.drexel.edu (Richard Friedman) wrote:
> 
> >Out of curiosity, Why do we need to grow the cells at 18oC prior to making
> >them competent? Seems pretty cold to me.
> 
> Also for E. coli membrane fluidity is critical. (Eu-) Bacteria
> maintain a constant fluidity by regulating the content of unsaturated
> fatty acids.
> If you lower temperature,  this will increase the amount of those
> fatty acids which will by disturbance through the C=C bonds facilitate
> the entry of foreign DNA.
> 
> I did not find this written, but it sounds pretty plausible.

An interesting speculation. My theory had been that more bacteria die and
lyse during growth at 37 C compared to <30 C, and that the released DNA
would compete with the plasmid DNA you want to transfect.

-- 
Ned Mantei
Dept. of Neurobiology, Swiss Federal Institute of Technology
CH-8093 Zurich, Switzerland
mantei at neuro.biol.ethz.ch   Fax: +41-1-633-1046



More information about the Methods mailing list