EcoRI problem

[Dr. Duncan Clark]

In article <33C50950.1059 at uvic.ca>, "Kris W." <kwilde at uvic.ca> writes
>The other day I was digesting a PCR-Script vector with EcoRI and I found
>that it cut at two sites when I was only expecting it to cut at one.  I
>normally leave the digestion for an hour or so but this time I left it
>for 3 hours.  I re-did the digestion for a half hour and found that
>there was only a single cut.  After looking at the sequence and the
>sizes of the fractions caused by the digestion I concluded that EcoRI
>(gaattc) cuts at aaattc when left for too long.  Similar sites such as
>gaattg were not cut.  
>
>Has anyone else noticed this or similar incidences with other
>restriction enzymes.

Classic star activity. Check out the appendix in a NEB catalogue.

Duncan
-- 
The problem with being on the cutting edge is that you occasionally get 
sliced from time to time....

Duncan Clark
DNAmp Ltd.
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http://www.dnamp.com
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