Smear in gel lanes (mini preps)

Dr.Sailesh Surapureddi SaiSu at MCB.LiU.SE
Sat Feb 3 00:45:43 EST 1996

>When I run out digested plasmid DNA from alkaline mini preps I 
>appropriate bandsas well as a smear throughout the lane.  When I 
>digested plasmid DNA isolated via qiagen maxi prep I did not see 
>smear.  I have not had this problem in the past!!  Is it 
possible >that 
>the cells that I am using could be the culprit.  The competent 
>that I used for transformations had thawed out, so I used them 
to >make 
>more competent cells.  Is it possible that this could be the 

I guess you are omitting the RNAse treatment and  with qiagen, 
the first buffer has RNAse in it already, so you are not seeing  
the smear.
Check out the RNAse, I am sure thats the culprit in your case.

												As I sail far far away...

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