32P into Supercoiled -No way ???

Thomas Hiesberger hiesi at mol.univie.ac.at
Mon Nov 28 09:47:59 EST 1994


In one of our experiments it would be necessary to label circular,
supercoiled plasmid DNA with 32 P. At first, it did not look difficult at
all. But now I am kind of desperate, because I can not think of a proper
way to do this, apart from making single strand DNA and synthesizing the
second strand using 32P nucleotides - I need huge amounts and do not get
it with this method.  The other possibility is to grow bacteria harboring
the plasmid in a medium containing 32P - The 32 P incorporation
efficiency seems not to be very high (32P would also incorporate into
genomic DNA and using chloramphenicol for amplification does probably not
go well together with 32P so I do not really want to go into this). But I
still think there must be a way of labeling I have not thought about. I
would be very grateful for any idea or advice. 

Thomas Hiesberger

More information about the Methods mailing list