FAST KINETIC-STUDIES OF PLASMID DNA TRANSFER IN INTACT YEAST-CELLS MEDIATED BY ELECTROPULSATION

Intact yeast cell Electrotransformation process was investigated. It is a two step process. The plasmid must be pre-mixed and present in contact with the cells during the pulse. During the millisecond field pulse, plasmid DNA is associated to the envelope. It therefore crosses the membrane by a process which lasts several seconds as shown by its sensitivity to a post pulse addition of DNase. Electrotransformation is not supported by an electrophoretic transfer due to the external field nor by a free diffusion across the electropermeabilized DNA is first bound during the field pulse and then is transferred by a still unknown active process due to cell metabolism. (C) 1995 Academic Press, Inc.