pulse field gels

[shelly may deane]

I need some advice as to what pulse parameters to choose in order to get 
large MW DNA fragments to migrate out of the wells on the Geneline Trans 
Alternating Field Electrophoresis system.  I can successfully separate 
fragments in the 150 - 1500 kb range using 1 min pulses at 150 mA for 18 h, 
but I notice I still have DNA in the wells under these conditions.  The 
Geneline system uses 6 day runs at 30 mA and 90 min pulses to separate out 
yeast chromosomes of 3000 - 9000 kb, but this is not applicable to my 
restriction digests of bacterial DNA for which the largest fragments should 
be about 2500 kb. Most of the references I come across are for various other 
types of pulse fields, so if anyone out there is familiar with the TAFE 
system specifically, I would appreciate hearing from you.
Email to shelly at molbiol.uct.ac.za

Dr Shelly Deane   Microbiology Dept.  University of Cape Town
"It is costly wisdom that is bought by experience" R. Ascham.