Submitted to: Biotechnology Techniques
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/3/2002
Publication Date: 2/1/2003
Citation: BASSETT, C.L., JANISIEWICZ, W.J. ELECTROPORATION AND STABLE MAINTENANCE OF PLASMID DNAS IN A BIOCONTROL STRAIN OF PSEUDOMONAS SYRINGAE. BIOTECHNOLOGY TECHNIQUES. Vol. 25, pgs. 199-203, February 2003. Interpretive Summary: The application of biological organisms to control plant diseases holds substantial promise for reducing the use of potentially harmful chemicals, particularly with regard to protecting stored fruit. At present, most biocontrol organisms used alone or in combination are not as effective as chemical pesticides in controlling fruit diseases. The possibility of greatly improving biocontrol capability by adding genes for enzymes known to be effective in controlling disease-causing microbes is an option that is just beginning to be explored. However, there are only a few reports of successfully transferring DNA into bacterial strains with demonstrated biocontrol ability. The current paper describes a protocol for efficiently delivering DNA into a commercially useful bacterial biocontrol strain used to protect stored fruit from diseases. In addition, stability of the DNA after transfer is demonstrated for two commonly used DNA vectors which can be maintained by the bacterium successfully for many generations without having to apply antibiotics. The results indicate that gene transfer to an important biological control organism is feasible.
Technical Abstract: Transformation efficiencies as high as 1.0 X 10 7 transformants/µg DNA have been reported for Pseudomonads using electroporation protocols established for E. coli with plasmid DNAs prepared from E. coli hosts. We report here a protocol for electroporation of plasmid DNAs into a biocontrol strain of Pseudomonas syringae which could not be electroporated by standard E. coli methods and demonstrate that the plasmids are stably maintained in the absence of selection.