Flagellar stator genes control a trophic shift from obligate to facultative predation and biofilm formation in a bacterial predator.

Unlabelled: The bacterial predator is considered to be obligatorily prey (host)-dependent (H-D), and thus unable to form biofilms. However, spontaneous host-independent (H-I) variants grow axenically and can form robust biofilms. A screen of 350 H-I mutants revealed that single mutations in stator genes or were sufficient to generate flagellar motility-defective H-I strains able to adhere to surfaces but unable to develop biofilms.