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Agarose Gel Electrophoresis of plasmid DNA - Agarose Gel Electrophortesis of plasmid DNA (Mar/06/2005 )

I have a pBSK+ phagemid of size 2958bp. I clone a gene of size 1167bp in this phagemid. Now, I subject the following to Agarose gel elctrophoresis:
(1) Uncut, native pBSK+, without insert.
(2) Uncut, pBSK, with my cloned insert.
So, they are basically closed circular DNAs.
What would be the band sizes against which I would observe the above 2 samples?
Please help... This is a student project.


You could run these samples against other closed circular plasmids to compare the sizes but it would probably be better to linearise the plasmid first. A closed circular plasmid will give a number of bands depending on the degree of supercoiling. What I would do would be to cut both plasmids with the restriction enzymes you used to clone so that you will be able to see that the fragment you cloned is the correct size.