Fig 5.

Requirement of flagellar filament for iEPS5 infection. iEPS5 adsorption to the wild-type strain (WT; SL1344), polyhook strain (ΔfliK; CH506), and its complementation strain (ΔfliK/pUHE-fliK; CH516). (A) Exponentially growing cells were infected with iEPS5 (MOI, 0.01) and incubated at 37°C. After centrifugation and filtration, the phage titer in the filtrate was determined by standard overlay assay. The results are expressed as means and standard deviations from triplicate assays. The concentrations of IPTG are 100, 200, and 500 μM for the complementation strain. (B and C) Bacterial challenge assay with iEPS5 (B) and Chi (C) to diverse flagellar types, including normal flagella (WT; SL1344), nonmotile flagella (ΔmotA; CH504), normal hook without filament (ΔfliC/ΔfljB; CH509), and polyhook without filament (ΔfliK; CH506). Each phage was added at an MOI of 0.1 to the bacterial culture after 1.5 h of incubation (time point 0).