Which band?

[Cornelius Krasel]

aplummer at raye-atm.rz.uni-frankfurt.de wrote:
> I have a seemingly simple question to ask that I can not quickly answer.
> I have often digested a vector with a RE with a single site within
> the vector.  After running the gel, instead of seeing 1 single band, I 
> observe 2.  I conclude that one of the bands is uncut vector, while the 
> other is cut.  My problem is that I do not know which is which
> (top/bottom).  Any help with this seemingly simple question would be
> greatly appreciated and would help expedite a rather difficult sub-
> cloning procedure.

Why don't you just put the control (i.e. undigested DNA) on your gel?
(You will be surprised to see that uncut vector usually gives two
 bands. Therefore I would assume that your single-cutter didn't cut
 at all.)

--Cornelius.

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/* Cornelius Krasel, U Wuerzburg, Dept. of Pharmacology, Versbacher Str. 9 */
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