DNA plasmid extraction trouble - (Sep/09/2004 )

Hi! I am having trouble getting plasmid DNA from Streptococcus gordonii which is a gram positive oral bacteria. I have tried three different protocols including a cesium chloride gradient. When I run my results on an agarose gel I either get nothing, or a smear which fills the lane. I assume the smear to be either chromosomal DNA or contaminant. If anyone has suggestions to give me a clean prep of only the plasmid DNA please post. It would be especially helpful if you have had success with a similar bacteria. I really need to get this plasmid for my work to move forward.

I'm no expert on it, but I assume it's the fact that they are gram+ that is causing the problem. Here is a kit that you might try if you cant get other things to work

http://www.cpg-biotech.com/mbpd/dna/plasming_prot.html

Good luck!