Bizarre!!!!!!!!!!!!

Paul N Hengen pnh at ncifcrf.gov
Mon Jan 27 11:01:47 EST 1997


G Garcia-asua (MBP95GG at shef.ac.uk) wrote:

> Well, can anyone explain this to me please?
> I do a random partial digest of bacterial genomic DNA with Sau 3A1, run 
> it on a gel, cut out and purify the 1-3 kb fragments from the smear. 
> Then, I do ligations of these RANDOMLY cut fragments into my expression 
> vector to attempt complementation analysis and guess what! ALL MY 
> TRANSFORMANTS seem to have inserts of exactly the same MW (not a 
> range of between 1 and 3 kb as expected). Could anyone tell me 
> (mbp95gg at sheffield.ac.uk) what is going on? 

They could all be siblings of the same transformant if you expressed the cells
for a long time after the transformation procedure. Do restriction digests of
different isolates with various enzymes give fragments of the same size too?

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