We have developed genetically engineered natural gut bacteria from the Formosan subterranean termite (Coptotermes formosanus) as a shuttle system to deliver, express and transfer foreign genes in a termite colony.
Bacterial strains were cultured from the termite gut and characterized by morphological, biochemical and molecular methods. The dominant gut flora consists of three novel isolates and several Enterobacteriaceae species.
We transformed natural gut bacteria with recombinant plasmids containing Ampicillin resistance genes and the Green Fluorescent Protein gene (GFP). In laboratory experiments, transformed bacteria were fed to workers of three different termite colonies. Transformed bacteria in termite guts were detected by growing the flora of the entire termite gut under selective conditions and checking the cultures visually for fluorescence.
We have shown that: (1) transformed bacteria are ingested by termites and the GFP marker gene is expressed in the termite gut; (2) transformed bacteria are rapidly transferred throughout a lab colony, even when the donor (initially fed with transformed bacteria) to recipient (not fed) ratio is as low as 1:25; (3) transformed bacteria establish a stable population in the termite gut for more than six weeks. Although transformed Enterobacteriaceae are transferred into soil, environmental persistence can be avoided by using anaerobic insect-specific bacteria as shuttles.
We are currently testing gene products for their efficacy to control termites. Genes found to be detrimental will be engineered into natural gut bacteria and introduced to termites.
Species 1: Isoptera Rhinotermitidae Coptotermes formosanus (Formosan subterranean termite)
Species 2: Enterobacteriales Enterobacteriaceae Enterobacter
Keywords: Insect management, GFP
Back to Ten-Minute Papers, Section Fb. Urban Entomology
Back to Ten-Minute Papers, Section E, F, Fa, Fb
Back to The 2003 ESA Annual Meeting and Exhibition