Author response: Bacterial flagella grow through an injection-diffusion mechanism

Renault, Thibaud T.; Abraham, Anthony O; Bergmiller, Tobias; Paradis, Guillaume; Rainville, Simon; Charpentier, Emmanuelle; Guet, Călin C.; Tu, Yuhai; Namba, Keiichi; Keener, James P.; Minamino, Tetsuo; Erhardt, Marc

doi:10.7554/elife.23136.026

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First, it was proposed that the secreted subunits interact head-to-tail inside the channel of the flagellum and that the folding of subunits at the tip of the growing filament provides a pulling force on the head-to-tail chain (Evans et al, 2013). A more recent model suggests that filament assembly is instead governed by an injection-diffusion mechanism in which the growth kinetics decrease quadratically, thus providing an explanation for why growth does not continue indefinitely (Chen et al, 2017;Hughes, 2017;Renault et al, 2017). For a recent review see (Renault et al, 2019).…”

Section: Introductionmentioning

confidence: 99%

Novel transient cytoplasmic rings stabilize assembling bacterial flagellar motors

et al. 2022

View full text Add to dashboard Cite

The process by which bacterial cells build their intricate flagellar motility apparatuses has long fascinated scientists. Our understanding of this process comes mainly from studies of purified flagella from two species, Escherichia coli and Salmonella enterica.Here, we used electron cryo-tomography (cryo-ET) to image the assembly of the flagellar motor in situ in diverse Proteobacteria: Hylemonella gracilis, Helicobacter pylori, Campylobacter jejuni, Pseudomonas aeruginosa, Pseudomonas fluorescens, and Shewanella oneidensis. Our results reveal the in situ structures of flagellar intermediates, beginning with the earliest flagellar type III secretion system core complex (fT3SScc) and MS-ring. In high-torque motors of Beta-, Gamma-, and Epsilon-proteobacteria, we discovered novel cytoplasmic rings that interact with the cytoplasmic torque ring formed by FliG. These rings, associated with the MSring, assemble very early and persist until the stators are recruited into their periplasmic ring; in their absence the stator ring does not assemble. By imaging mutants in Helicobacter pylori, we found that the fT3SScc proteins FliO and FliQ are required for the assembly of these novel cytoplasmic rings. Our results show that rather than a simple accretion of components, flagellar motor assembly is a dynamic process in which accessory components interact transiently to assist in building the complex nanomachine.

show abstract