Optimization of the transformation of lactic acid bacteria
Electroporation has become the widest used method for introduction of foreign DNA into lactic acid bacteria. Our objective is to provide optimized electroporation protocols for our Lactobacillus and Enterococcus strains.
Several protocols for the electrotransformation of different Lactobacillus ssp. have been published and it turned out that only selected strains could be transformed with high efficiency. Because of strain variations, it is necessary to optimize the electroporation conditions for every LAB strain to obtain efficient genetic transfer. The efficiency of electrotransformation is affected by a number of parameters including the growth phase at which cells are harvested, cell density, composition of the wash and electroporation solutions, the inclusion of cell wall weakening agents in the growth medium and electric conditions such as electrical pulse strength and length.