High efficiency of direct plasmid transfer between two Streptomyces spp., and between Streptomyces spp. and E.coli

Electroduction is a method which allows direct transfer of plasmid DNA between donor and recipient under conditions of electroporation The application of this technique allows significantly faster analysis of streptomycetes transformants by omitting plasmid DNA purification. Here, we describe improved procedure with substantial modifications which allows direct plasmid shuttling between Streptomyces spp. and E. coli. Three different Streptomyces spp. (S. lividans, S. rimosus and S. coelicolor) and three E. coli strains were effective donors or recipients. The method was successfully applied to transfer three different bifunctional vectors: pFD666, pZG5 and pRM5, varying in size from 5 kb to 21 kb. The efficiency of plasmid transfer by novel method was significantly increased in comparison to our previously published results. In addition, we succeeded for the first time: a) to transfer plasmid of 21 kb, and b) to transfer plasmid DNA directly from S. lividans to S. rimosus.