lambda won't cut

[Martin Kennedy]

In article <9209091448.AA23264 at server.uga.edu>, mcgraw%gandal.dnet at SERVER.UGA.EDU writes:
> 
> 
> Hello netters,
> 
> A colleague provided us with some lambda clone DNAs "purified" from plate
> lysates.  They won't cut with EcoR1.  We tried further purification with
> additional phenol/chloroform extractions.  The uncut DNA looks good on a
> gel, and the OD's are good.  The inserts should cut out with EcoR1 based on
> the way the library was made (R1 linkers).  We haven't worked with lambda
> in quite a while, but I imagine that some of you out there are cutting
> yours successfully as you read this.
> 
> What do you suggest?
> 
>                                 Mike Grosse
>                                 McGraw lab
>                                 University of Georgia
> 




Mike - 

Have you tried adding spermidine to 4mM in your digetions? This can make  a big
difference with lambda preps.  Also, try cutting less DNA in a bigger volume.

Cheers, 

Martin