Qiagen Maxi: Quantity

[Gerd Romanowski]

In article <4l52rh$jvb at mailhost.zeneca.co.uk>,
   john brennand <john.brennand at gbapr.zeneca.com> wrote:
>Armin
>
>Just a thought.
>
>Is it possible that the problem is in the cultures - ie the bugs dont 
>contain as much plasmid as you think, because, for example, the 
>antibiotic levels are too low or it has gone off and plasmid free 
>segregants are overgrowing the culture ?
>
>You could check this by 1st doing a miniprep from the culture, by an 
>alternative method, and then from the result predicting how much you 
>should get from the whole culture.
>
>John
>
>
>


I already did that: Qiagen minipreps are o.k. in quality and quantity.

Ampicillin is 200 µg/ml. That should be optimal. Is it a known "bug" with pUC 

and pBR, that plasmidless segregants are overgrowing the culture? I dont't 

think that this is a real problem because segregants without plasmid cannot 

grow and the culture is logarithmic.





Armin