Like all organisms, plants are associated with bacterial communities in which helpful and harmful bacteria compete for dominance. Among the weaponry of these warring bacteria are molecular syringes that some bacteria can use to inject toxins into others. In a study published in the Feb. 2 issue of the Journal of Biological Chemistry, researchers at McMaster University in Canada pinpointed the identity of one such toxin used by a soil-dwelling bacterium that protects plants from disease.