Tle1AHis required for the interbacterial antagonism ofA. hydrophilaNJ-35. Predator and prey cells at a ratio of 5:1 were cocultured to assay the recovery of surviving prey cells by determining colony forming unit (CFU). A. hydrophila NJ-35 and its mutant derivatives ∆clpV, ∆tle1AH or C∆tle1AH were used as the predator strains. ClpV, which encodes a putative ATPase required for T6SS function, was deleted to construct the T6SS− strain (∆clpV). “LB” indicates incubation of E. coli with sterile LB medium alone and serves as the control. AE. coli BL21 as the prey strain. BV. parahaemolyticus RIMD 2210633 as the prey strain. CAeromonas strains as the preys, including A. hydrophila strains ATCC 7966, J-1 and NJ-3, A. sobria CS-2, A. media NJ-8 and A. veronii XH-14. Lane 1, the wild-type A. hydrophila NJ-35; Lane 2, ∆clpV (T6SS−); Lane 3, ∆tle1AH. Data are presented as the mean ± standard deviation (error bars) of three independent experiments. ***P < 0.001, **P < 0.01. *P < 0.05.