Electroporation at elevated temperatures substantially improves transformation efficiency of slow-growing mycobacteria

FEMS Microbiol Lett. 1996 Nov 15;145(1):101-5. doi: 10.1111/j.1574-6968.1996.tb08563.x.


The effects of electroporation temperature, biochemical pretreatment of cells and stage of culture on electroporation efficiency for slow-growing mycobacteria were investigated. The efficiency of transformation into Mycobacterium tuberculosis, Mycobacterium bovis and Mycobacterium intracellulare increased markedly with temperature. In contrast, the efficiency of transformation into Mycobacterium smegmatis, a fast-growing species, was higher at 0 degree C and decreased with temperature. While stage of culture had little effect, a further increase in efficiency of 2-4-fold was obtained following glycine or ethionamide pretreatment. Electroporation at 37 degrees C has been chosen as a standard condition for slow-growing species as it usually resulted in a transformation efficiency several orders of magnitude higher than that obtained at 0 degree C.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteriological Techniques
  • Cosmids
  • DNA, Bacterial / genetics
  • Electroporation / methods*
  • Hot Temperature
  • Mycobacterium / genetics*
  • Mycobacterium / growth & development
  • Mycobacterium avium Complex / genetics
  • Mycobacterium avium Complex / growth & development
  • Mycobacterium bovis / genetics
  • Mycobacterium bovis / growth & development
  • Mycobacterium tuberculosis / genetics
  • Mycobacterium tuberculosis / growth & development
  • Plasmids


  • DNA, Bacterial