2 replies to this topic

[tantao]

Dear all,
I  have got  a problem about plasmid purificaiton. After the plasmid purificaiton, I ran plasmid DNA on a gel , but there is an another band  before super colied plasmid .
I do not know what happened . Do you have any suggestions?  Thanks a lot!

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Edited by tantao, 21 October 2009 - 11:40 PM.

[leelee]

I'm assuming it is uncut plasmid? In which case it is probably your plasmid in another conformational state, like relaxed circular.......which runs slower than the supercoiled.

[tantao]

leelee, on Oct 22 2009, 02:04 PM, said:

I'm assuming it is uncut plasmid? In which case it is probably your plasmid in another conformational state, like relaxed circular.......which runs slower than the supercoiled.

Dear leelee,
maybe I do not explain this problem clearly. so  I  edit my photo, and  the stranger band, I have marked it with asterisk.. I do not digest the plasmid with any enzyme, there should be no band! so  I do not know what happened!