The development of a transformation system in Lactobacillus plantarum

Lactobacilli are part of the normal gut microflora in man and animals and play a major role in food fermentations. However, little is known about the genetics of these organisms owing to the lack of a reliable system for genetic manipulations. Using L. plantarum as a model, this study was undertaken to devise a system of transformation for lactobacilli. A method for producing, regenerating and transfecting protoplasts of L. plantarum was developed.; Using electroporation, L. plantarum was transformed with the temperature sensitive plasmid pTV1Ts which carries the transposon Tn917. After several passages at 40{dollar}spcirc{dollar}C, random insertions of Tn917 into host DNA with the subsequent loss of the vector pTV1Ts were detected. These results show that transpositional mutagenesis using Tn917 is feasible in L. plantarum and possibly other lactobacilli.