title: Interaction of FliS flagellar chaperone with flagellin.
abstract: Premature polymerization of flagellin (FliC), the main component of flagellar filaments, is prevented by the FliS chaperone in the cytosol. Interaction of FliS with flagellin was characterized by isothermal titration calorimetry producing an association constant of 1.9x10(7) M-1 and a binding stoichiometry of 1:1. Experiments with truncated FliC fragments demonstrated that the C-terminal disordered region of flagellin is essential for FliS binding. As revealed by thermal unfolding experiments, FliS does not function as an antifolding factor keeping flagellin in a secretion-competent conformation. Instead, FliS binding facilitates the formation of alpha-helical secondary structure in the chaperone binding region of flagellin.
authors.affiliation: Department of Nanotechnology, Faculty of Information Technology, Pannon University, Egyetem u. 10, H-8200 Veszprém, Hungary.
authors.forename: Adél
authors.initials: A
authors.lastname: Muskotál
authors.forename: Réka
authors.initials: R
authors.lastname: Király
authors.forename: Anett
authors.initials: A
authors.lastname: Sebestyén
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Gugolya
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Végh
authors.forename: Ferenc
authors.initials: F
authors.lastname: Vonderviszt
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D002152:Calorimetry, Differential Scanning; D002942:Circular Dichroism; D005407:Flagella / Q000737:chemistry* / Q000378:metabolism*; D005408:Flagellin / Q000737:chemistry / Q000378:metabolism*; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D012486:Salmonella typhimurium / Q000737:chemistry / Q000166:cytology; D013696:Temperature; D013816:Thermodynamics; D017186:Titrimetry
chemical_list: D001426:Bacterial Proteins; D018832:Molecular Chaperones; D005408:Flagellin; C076734:FliS protein, Bacteria