Electroporation-transformation System for Coryneform Bacteria by Auxotrophic Complementation

Abstract

We evaluated electroporation as an alternative system for genetic exchange for one of the coryneform bacteria, Brevibacterium flavum MJ233. The maximum number of transformants, 6 × 104 cells, was obtained when cells were cultured with Penicillin G (1 U/ml) and harvested at the middle-log phase. Electroporation was done using 12.5kV/cm of pulse field strength, 1×1010 cells, and 1 μg of plasmid DNA. Other coryneform bacteria, Brevibacterium lactofermentum ATCC 13869, Corynebacterium glutamicum ATCC 31830, and B. stationis IFO 12144 were also transformed by electroporation. Electroporation has the advantage that intact cells can be used as host cells without the need for protoplast formation and regeneration. Moreover, minimal medium can be used, so auxotrophic complementation of the transformants is possible. © 1990, Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.