title: The role of FlhF and HubP as polar landmark proteins in Shewanella putrefaciens CN-32.
abstract: Spatiotemporal regulation of cell polarity plays a role in many fundamental processes in bacteria and often relies on 'landmark' proteins which recruit the corresponding clients to their designated position. Here, we explored the localization of two multi-protein complexes, the polar flagellar motor and the chemotaxis array, in Shewanella putrefaciens CN-32. We demonstrate that polar positioning of the flagellar system, but not of the chemotaxis system, depends on the GTPase FlhF. In contrast, the chemotaxis array is recruited by a transmembrane protein which we identified as the functional ortholog of Vibrio cholerae HubP. Mediated by its periplasmic N-terminal LysM domain, SpHubP exhibits an FlhF-independent localization pattern during cell cycle similar to its Vibrio counterpart and also has a role in proper chromosome segregation. In addition, while not affecting flagellar positioning, SpHubP is crucial for normal flagellar function and is involved in type IV pili-mediated twitching motility. We hypothesize that a group of HubP/FimV homologs, characterized by a rather conserved N-terminal periplasmic section required for polar targeting and a highly variable acidic cytoplasmic part, primarily mediating recruitment of client proteins, serves as polar markers in various bacterial species with respect to different cellular functions.
authors.affiliation: Department of Microbiology and Molecular Biology, Justus-Liebig Universität, 35392, Giessen, Germany.|Department of Ecophysiology, Max-Planck-Institut für terrestrische Mikrobiologie, 35043, Marburg, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Rossmann
authors.affiliation: Department of Microbiology and Molecular Biology, Justus-Liebig Universität, 35392, Giessen, Germany.|Department of Ecophysiology, Max-Planck-Institut für terrestrische Mikrobiologie, 35043, Marburg, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Brenzinger
authors.affiliation: LOEWE Center for Synthetic Microbiology (Synmikro) & Department of Chemistry, Philipps University Marburg, 35043, Marburg, Germany.
authors.forename: Carina
authors.initials: C
authors.lastname: Knauer
authors.affiliation: Department of Microbiology and Molecular Biology, Justus-Liebig Universität, 35392, Giessen, Germany.
authors.forename: Anja K
authors.initials: AK
authors.lastname: Dörrich
authors.affiliation: Department of Microbiology and Molecular Biology, Justus-Liebig Universität, 35392, Giessen, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bubendorfer
authors.affiliation: Department of Microbiology and Molecular Biology, Justus-Liebig Universität, 35392, Giessen, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Ruppert
authors.affiliation: LOEWE Center for Synthetic Microbiology (Synmikro) & Department of Chemistry, Philipps University Marburg, 35043, Marburg, Germany.
authors.forename: Gert
authors.initials: G
authors.lastname: Bange
authors.affiliation: Department of Microbiology and Molecular Biology, Justus-Liebig Universität, 35392, Giessen, Germany.
authors.forename: Kai M
authors.initials: KM
authors.lastname: Thormann
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism / Q000502:physiology*; D002633:Chemotaxis; D020090:Chromosome Segregation; D010861:Fimbriae, Bacterial / Q000378:metabolism; D005407:Flagella / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D008565:Membrane Proteins / Q000378:metabolism; D020559:Monomeric GTP-Binding Proteins / Q000502:physiology*; D020614:Shewanella putrefaciens / Q000737:chemistry / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure; D014734:Vibrio cholerae / Q000737:chemistry / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; C078317:flhF protein, Bacteria; D020559:Monomeric GTP-Binding Proteins