Electrotransformation of Lactobacillus manihotivorans LMG 18010(T) and LMG18011

An electroporation procedure was developed for the genetic transformation o f intact cells of Lactobacillus manihotivorans, a new Lactobacillus species isolated from cassava sour starch fermentation in Colombia. Transformation efficiency of Lact. manihotivorans strains LMG 18010(T) and LMG 18011 was measured and compared with electroporability of Lact. plantarum strains NCI MB 8299 and LMG 9211, by investigating the effect of changes in various par ameters. For Lact. manihotivorans strain LMG 18010(T), the composition of t he 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 cond itions 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 el ectroporability. Transformants were obtained with Lact. manihotivorans stra in LMG 18010(T) and the plasmids pLZ12 and pGK13, whereas Lact. manihotivor ans strain LMG. 18011 was transformable with plasmids pLP825 and pLZ12, wit h different electroporation conditions.