[Plasmid DNA transformation of Yersinia pseudotuberculosis by electroporation]

Rendering cells permeable to DNA molecules, electroporation involves the application of high intensity electric fields of short duration to reversibly change the biomembranes, which has been used successfully in some species of both gram negative and positive bacteria. We first reported the electro-transformation technics of Yersinia pseudotuberculosis. The plasmid pJGX20 was constructed by cloning the 9.5 kb plasmid encoding pesticin into Pst I site of pBR328. Transformation efficiency of 103 transformants/micrograms DNA was obtained at voltage of 1300V or 1400V, capacity of 25 microF, time constant of 48-52 msec, with 10% glycerol as electroporation buffer. The pesticin gene of pJGX20 was expressed well in Y. pseudotuberculosis.