Electrotransformation of Lactobacillus manihotivorans LMG 18010T and LMG 18011

An electroporation procedure was developed for the genetic transformation of intact cells of #Lactobacillus manihotivorans$, a new #Lactobacillus$ species isolated from cassava sour starch fermentation in Colombia. Transformation efficiency of #Lact. manihotivorans$ strains LMG 18010T and LMG 18011 was measured and compared with electroporability of #Lact. plantarum$ strains NCIMB 8299 and LMG 9211, by investigating the effect of changes in various parameters. For #Lact. manihotivorans$ strain LMG 18010T, the composition of the culture medium, such as the type of peptone and the presence of Tween-80, was found to be the most critical parameter, as well as the aeration conditions of the culture ; better electroporation was obtained without air. The presence of MgCl2 in the recovery medium was favourable to regeneration of electroporated cells. Plasmid-curing of the cells did not improve their electroporability. Transformants were obtained with #Lact. manihotivorans$ strain LMG 18010T and the plasmids pLZ12 and pGK13, whereas #Lact. manihotivorans$ strain LMG 18011 was transformable with plasmids pLP825 and pL/Z12, with different electroporation conditions. (Résumé d'auteur