FliL and its paralog MotF have distinct roles in the stator activity of the Sinorhizobium meliloti flagellar motor.
Mol Microbiol
; 118(3): 223-243, 2022 09.
Article
em En
| MEDLINE
| ID: mdl-35808893
ABSTRACT
The bacterial flagellum is a complex macromolecular machine that drives bacteria through diverse fluid environments. Although many components of the flagellar motor are conserved across species, the roles of FliL are numerous and species-specific. Here, we have characterized an additional player required for flagellar motor function in Sinorhizobium meliloti, MotF, which we have identified as a FliL paralog. We performed a comparative analysis of MotF and FliL, identified interaction partners through bacterial two-hybrid and pull-down assays, and investigated their roles in motility and motor rotation. Both proteins form homooligomers, and interact with each other, and with the stator proteins MotA and MotB. The ∆motF mutant exhibits normal flagellation but its swimming behavior and flagellar motor activity are severely impaired and erratic. In contrast, the ∆fliL mutant is mostly aflagellate and nonmotile. Amino acid substitutions in cytoplasmic regions of MotA or disruption of the proton channel plug of MotB partially restored motor activity to the ∆motF but not the ∆fliL mutant. Altogether, our findings indicate that both, MotF and FliL, are essential for flagellar motor torque generation in S. meliloti. FliL may serve as a scaffold for stator integration into the motor, and MotF is required for proton channel modulation.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sinorhizobium meliloti
/
Flagelos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Mol Microbiol
Ano de publicação:
2022
Tipo de documento:
Article