"Deciphering Bacterial 'Syringe' Loading: Shuttle Complexes and Pathogen Tactics"

Researchers have uncovered how the 'sorting platform' protein complexes in the bacterium Yersinia enterocolitica shuttle virulence effectors to the type III secretion system (T3SS), a mechanism critical for bacterial infection. Using in vivo proximity labeling and single-particle tracking super-resolution microscopy, they demonstrated that the sorting platform components SctQ and SctL directly interact with T3SS effectors in the cytosol, even in the absence of other essential T3SS membrane components. This interaction is dynamic and adjusts to external conditions, providing new insights into the initial steps of type III secretion and the path of T3SS effectors before their translocation into host cells. These findings could inform future research on targeted inhibition of bacterial secretion systems.