Big Size of Plasmid Transformation - Urgent! (Apr/08/2003 )

Help!
I have trouble in transforming a big size of plasmid (about 40kb) into the competent cells. Since the recombinant plasmid is generated by homologous recombinant reaction, I can not use electroporation which needs large amount of DNA. I used normal competent cells (eg. Top 10, DH5alpha), heat shock method and got no colony after plating on LB plates with Amp as selective antibiotic.
Any good suggestion?

where do u get the idea that electroporation needs large amount of DNA?
the efficiency of heat shock is much lower than electrooration, and for such a
big plasmid, elctroportion is a practical way. Don't care about the amount of
ur DNA.Good luck.