Yeast plasmid DNA extraction

[Dimuth Siritunga]

I was wandering whether there is any one who can help me with the following 
problem I'm having.

I am trying to isolate plasmid DNA from yst and transform bacteria with them 
to amplify the amount of plasmid DNA from my yst transformants.  Although the 
yeast DNA concentration after the extraction seems to be high and clean (after 
RNase as well) I am not able to transform bacteria with them.  But the 
positive control of pUC18 gives the good transformation under the same 
conditions.

Is there any thing special I should be doing? and is there any specific good 
protocols on the web? any help in this area will be highly appreciated. My 
email is 'siritunga.1 at osu.edu'.

Thanking you in advance
Sincerely
Dimuth Siritunga