Functional divergence of flagellar type III secretion system: A case study in a non-flagellated predatory bacterium

摘要

Flagellar type III secretion system (FT3SS) is widely employed by flagellated bacteria to transport flagellar subunit proteins for flagellum assembly in vivo and for motility (upper). We found that in a soil, non-flagellated bacterium known as Lysobacter enzymogenes OH11, the remaining FT3SS genes appear to assemble a functional FT3SS-like system, which most likely undergoes a functional divergence to mediate the export of antifungal toxins to inhibit the growth of co-habited fungi (bottom), thereby strengthening its predatory capacity.