I have a low copy number plasmid that I need to cut with EcoR1, but the
digestions so far have been incomplete. Since it is low copy,and a
regular miniprep doesn't give enough DNA, I used a maxi prep kit from
Promega. I seem to remember hearing complaints from people that DNA
purified in this manner is difficult to cut with some enzymes, apparently
due to something from the DNA binding resin.
Anyhow, has anyone else had trouble with this? Is there some way to clean
up the DNA so that it will cut with R1? If not, what is the best way to
get enough plasmid to work with? Large scale alkaline lysis?
BTW, EtOH precipitation does not help.
Thanks for any suggestions!