Toxin-producing strains of Bacillus thuringiensis bacteria are virulent pathogens of cabbage-eating caterpillars. But strains that don’t produce toxins are also able to infect the insects, by piggy-backing on the hard work of their toxin-producing brethren. A paper published today (July 5) in Science describes the first field observations of this freeloading behavior and the relationship dynamics between the exploiting and exploited bacteria—information that could lead to more effective caterpillar-killing biopesticide approaches, and that might even have implications for human health.
“It is really interesting and important because it shows for the first time in a natural host-pathogen system that social interaction is important for understanding the evolution of pathogen virulence,” said Jeff Smith of Washington University in Saint Louis, who did not participate in the ...
