Ejection of the γ-proteobacterial flagellum is triggered by nutrient depletion.

(A) Cells continually diluted to low cell density do not lose flagella (***P P. shigelloides spent medium lose flagella within one doubling time (***P Salmonella spent medium lose flagella within one doubling time (***P t test). At least 75 cells were analyzed for each sample. (D) Cells eject flagella when transferred from LB to MOPS minimal medium (***P t test). At least 60 cells were analyzed for each sample. (E) The ejection of flagella in minimal medium is rescued by the addition of yeast extract. More than 70 cells were imaged for each sample (***P S1 Data. c-di-GMP, cyclic di-GMP; FlgE, hook; FliC, filament; LB, Lysogeny Broth; OD, optical density.