title: Specificity of motor components in the dual flagellar system of Shewanella putrefaciens CN-32.
abstract: Bacterial flagellar motors are intricate nanomachines in which the stator units and rotor component FliM may be dynamically exchanged during function. Similar to other bacterial species, the gammaproteobacterium Shewanella putrefaciens CN-32 possesses a complete secondary flagellar system along with a corresponding stator unit. Expression of the secondary system occurs during planktonic growth in complex media and leads to the formation of a subpopulation with one or more additional flagella at random positions in addition to the primary polar system. We used physiological and phenotypic characterizations of defined mutants in concert with fluorescent microscopy on labelled components of the two different systems, the stator proteins PomB and MotB, the rotor components FliM(1) and FliM(2), and the auxiliary motor components MotX and MotY, to determine localization, function and dynamics of the proteins in the flagellar motors. The results demonstrate that the polar flagellum is driven by a Na(+)-dependent FliM(1)/PomAB/MotX/MotY flagellar motor while the secondary system is rotated by a H(+)-dependent FliM(2)/MotAB motor. The components were highly specific for their corresponding motor and are unlikely to be extensively swapped or shared between the two flagellar systems under planktonic conditions. The results have implications for both specificity and dynamics of flagellar motor components.
authors.affiliation: Department of Ecophysiology, Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bubendorfer
authors.forename: Susanne
authors.initials: S
authors.lastname: Held
authors.forename: Natalie
authors.initials: N
authors.lastname: Windel
authors.forename: Anja
authors.initials: A
authors.lastname: Paulick
authors.forename: Andreas
authors.initials: A
authors.lastname: Klingl
authors.forename: Kai M
authors.initials: KM
authors.lastname: Thormann
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D005407:Flagella / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017930:Genes, Reporter; D008124:Locomotion; D008856:Microscopy, Fluorescence; D020409:Molecular Motor Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011485:Protein Binding; D025941:Protein Interaction Mapping; D017494:Proton Pumps / Q000378:metabolism; D020614:Shewanella putrefaciens / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013194:Staining and Labeling / Q000379:methods
chemical_list: D001426:Bacterial Proteins; D020409:Molecular Motor Proteins; D017494:Proton Pumps; D000254:Sodium-Potassium-Exchanging ATPase