title: Role of the MotB linker in the assembly and activation of the bacterial flagellar motor.
abstract: Bacterial flagella are driven by an ion influx through the peptidoglycan (PG)-tethered MotA/MotB stator. Stator precomplexes assemble in the membrane and remain inactive until they incorporate into the motor, upon which MotA/MotB changes conformation. The nature of this change and the mechanism of inhibition of the PG-binding and ion-conducting activities of the precomplexes are unknown. Here, the structural analysis of a series of N-terminally truncated MotB fragments is presented, the mechanism of inhibition by the linker is identified and the structural basis for the formation of the PG-binding-competent open-channel MotA/MotB conformation via a mechanism that entails linker unfolding and rotational displacement of MotB transmembrane helices is uncovered.
authors: Manchester Interdisciplinary Biocentre, University of Manchester, 131 Princess Street, Manchester M1 7DN, England.
authors: Jenna
authors: J
authors: O'Neill
authors: Meng
authors: M
authors: Xie
authors: Marcel
authors: M
authors: Hijnen
authors: Anna
authors: A
authors: Roujeinikova
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D005407:Flagella / Q000737:chemistry* / Q000378:metabolism; D016480:Helicobacter pylori / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D017510:Protein Folding; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; C064779:MotB protein, Bacteria