Abstract:

The objective of this work was to explore an efficient method for Lactobacillus plantarum G63
electrotransformation. We evaluated the effects of the growth phase, weakening cells, washing buffer, plasmid
DNA concentration and electrical parameters on electroporation efficiency. The results showed that after culture in
MRS medium containing 1 g/100 mL glycine to mid-logarithmic phase, the cells were harvested and washed with
1 mmol/L MgCl2 and 30 g/100 mL PEG1000. The optimal electroporation conditions could be achieved by using 30 g/100 mL
PEG1000 as the electroporation buffer with 20 μg of plasmid DNA added in 80 μL of the cell suspension, and pulsing under
specific conditions (field strength, 1.5 kV; resistance, 400 Ω). The transformation efficiency was 1.18 × 103 CFU/μg DNA
under the optimal conditions, which could meet the requirements for subsequent genetic experiments.

Key words: Lactobacillus plantarum, electroporation, transformation efficiency