Translocator proteins in P. aeruginosa or S. typhimuriurm, does not result in loss of effector secretion control (Broms et al., 2003, Cisz et al., 2008, Kaniga et al., 1995b). Another variation of the plug model has been proposed, where a `sensor' protein has been inserted into the type III secretion channel (Blocker et al., 2008). Its export is inhibited by the type III secretion needle-tip and i