Structure and Activity of the Flagellar Rotor Protein FliY

Sircar, Ria; Greenswag, Anna R.; Bilwes, A.M.; Gonzalez-Bonet, Gabriela; Crane, Brian R.

doi:10.1074/jbc.m112.445171

Cited by 38 publications

(48 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We previously reported that the FliM-FliG interaction is conserved and that they form the upper part of the C-ring (20). The FliY-FliN interaction is predicted to assemble at the bottom part of the switch complex through the interaction with FliY-FliM, resulting in a donut-shaped dimer of heterodimers (21). The FliY N domain did not interact with other switch proteins and is likely located at the periphery of the C-ring.…”

Section: Discussionmentioning

confidence: 99%

“…The FliY truncation mutant showed a clockwise rotational bias, which seems consistent with its potential role as a CheY phosphatase. However, the H. pylori FliY lacks a CheY-binding sequence that is required for the CheY dephosphorylation in B. subtilis (21,35). A sequence analysis showed that FliY N contained one putative phosphatase consensus motif, -EXXXN-, which is slightly different from the consensus -EXXN-motif in the CheC/CheX/FliY family and the -EXXXQ-motif in CheZ (52).…”

Section: Discussionmentioning

confidence: 99%

“…The structure of the FliY middle (FliY M ) domain from T. maritima was resolved recently, highlighting its structural homology to FliM. One difference between FliM and FliY M is that the latter evolved to contain two EXXN phosphatase motifs, and both motifs display phosphatase activity towards CheY (21). Interestingly, the gastric pathogen H. pylori and related Epsilonproteobacteria encode both FliN and FliY (5,36).…”

mentioning

confidence: 99%

“…The motor C-rings of these bacteria contain 26 copies of FliG, 34 copies of FliM and >110 copies of FliN (7)(8)(9). Most of these structures were determined using proteins from other organisms, and their assembly models have been recently proposed (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). Electron microscopic and tomographic studies have shown that the organization of the switch proteins is similar across different species such that FliG is the closest to the cytoplasmic membrane, followed by FliM and FliN is found in a distant membrane location, toward the cytoplasm ( Figure 1A) (4,23,24).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Three SpoA-domain proteins interact in the creation of the flagellar type III secretion system in Helicobacter pylori

Lam

Xue

Sun

et al. 2018

Journal of Biological Chemistry

View full text Add to dashboard Cite

Bacterial flagella are rotary nano-machines that contribute to bacterial fitness in many settings, including host colonization. The flagellar motor relies on the multiprotein flagellar motor-switch complex to govern flagellum formation and rotational direction. Different bacteria exhibit great diversity in their flagellar motors. One such variation is exemplified by the motor-switch apparatus of the gastric pathogen Helicobacter pylori, which carries an extra switch protein, FliY, along with the more typical FliG, FliM, and FliN proteins. All switch proteins are needed for normal flagellation and motility in H. pylori, but the molecular mechanism of their assembly is unknown. To fill this gap, we examined the interactions among these proteins. We found that the C-terminal SpoA domain of FliY (FliY C ) is critical to flagellation and forms heterodimeric complexes with the FliN and FliM SpoA domains, which are β-sheet domains of type III secretion system proteins. Surprisingly, unlike in other flagellar switch systems, neither FliY nor FliN self-associated. The crystal structure of the FliY C -FliN C complex revealed a saddle-shape structure homologous to the FliN-FliN dimer of Thermotoga maritima, consistent with a FliY-FliN heterodimer forming the functional unit. Analysis of the FliY C -FliN C interface indicated that oppositely charged residues specific to each protein drive heterodimer formation. Moreover, both FliY C -FliM C and FliY C -FliN C associated with the flagellar regulatory protein FliH, explaining their important roles in flagellation. We conclude that H. pylori uses a FliY-FliN heterodimer instead of a homodimer and creates a switch complex with SpoA domains derived from three distinct proteins.Bacterial flagella are rotary nano-machines that contribute to bacterial fitness in a variety of settings, including mammalian and plant colonization (1,2). Although the basic function of flagella as a motor organelle is conserved, substantial variation exists among microbes in the components used to build and operate key aspects of the flagella. For example, we now know that there are diverse motor structures from cryo-electron tomography studies (3,4), and that bacterial motors consist of FliG, FliM and either FliN or FliY or the combination of both FliN and FliY (5) The flagellar motor switch complex, also called the C-ring, is found at the base of each flagellum and resides within the cytoplasm (6). It plays an important role in flagellar assembly, torque generation, and rotational switching. Numerous studies have dissected the composition, arrangement, and structure of the switch proteins, with a focus on those from Escherichia coli and Salmonella typhimurium that possess FliG, FliM and FliN. The motor C-rings of these bacteria contain 26 copies of FliG, 34 copies of FliM and >110 copies of . Most of these structures were determined using proteins from other organisms, and their assembly models have been recently proposed (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). Electron microscop...

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Three SpoA-domain proteins interact in the creation of the flagellar type III secretion system in Helicobacter pylori

Lam

Xue

Sun

et al. 2018

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…32; 33 Some bacteria such as Thermotogae and Bacilli , contain FliY, which is FliN fused to an additional CheY-P phosphatase domain. 34; 35; 36; 37; 38; 39 The FliG N-terminal domain (FliG N ) interacts with FliF in the smaller, membrane-situated MS-ring (membrane and supramembranous ring). 40 Fusions of FliF with truncated versions of FliG produce assembled rotors with altered EM density at the top of the C-ring.…”

Section: Introductionmentioning

confidence: 99%

Assembly States of FliM and FliG within the Flagellar Switch Complex

Sircar

Borbat

Lynch

et al. 2015

Journal of Molecular Biology

Self Cite

View full text Add to dashboard Cite

At the base of the bacterial flagella a cytoplasmic rotor (the C-ring) generates torque and reverses rotation sense in response to stimuli. The bulk of the C-ring forms from many copies of the proteins FliG, FliM, and FliN, which together constitute the switch complex. To help resolve outstanding issues regarding C-ring architecture, interactions between FliM and FliG from Thermotoga maritima have been investigated with x-ray crystallography and pulsed dipolar electron spin resonance spectroscopy (PDS). A new crystal structure of an 11-unit FliG:FliM complex produces a large arc with a curvature consistent with the dimensions of the C-ring. Previously determined structures along with this new structure provided a basis to test switch complex assembly models. PDS combined with mutational studies and targeted cross-linking reveal that FliM and FliG interact through their middle domains to form both parallel and antiparallel arrangements in solution. Residue substitutions at predicted interfaces disrupt higher-order complexes that are primarily mediated by contacts between the C-terminal domain of FliG and the middle domain of a neighboring FliG molecule. Spin separations among multi-labeled component proteins fit to a self-consistent model that agrees well with electron microscopy images of the C-ring. An activated form of the response regulator CheY destabilizes the parallel arrangement of FliM molecules to perturb FliG alignment in a process that may reflect the onset of rotation switching. This data suggest a model of C-ring assembly in which intermolecular contacts among FliG domains provide a template for FliM assembly and cooperative transitions.

show abstract

Complete genome of Sphingomonas paucimobilis ZJSH1, an endophytic bacterium from Dendrobium officinale with stress resistance and growth promotion potential

Qian

et al. 2023

Arch Microbiol

View full text Add to dashboard Cite

Structure and Activity of the Flagellar Rotor Protein FliY

Cited by 38 publications

References 58 publications

Three SpoA-domain proteins interact in the creation of the flagellar type III secretion system in Helicobacter pylori

Three SpoA-domain proteins interact in the creation of the flagellar type III secretion system in Helicobacter pylori

Assembly States of FliM and FliG within the Flagellar Switch Complex

Complete genome of Sphingomonas paucimobilis ZJSH1, an endophytic bacterium from Dendrobium officinale with stress resistance and growth promotion potential

Contact Info

Product

Resources

About