Learn More
The bacterial flagellar filament is a helical propeller for bacterial locomotion. It is a helical assembly of a single protein, flagellin, and its tubular structure is formed by 11 protofilaments in two distinct conformations, L- and R-type, for supercoiling. The X-ray crystal structure of a flagellin fragment lacking about 100 terminal residues revealed(More)
F-actin is a helical assembly of actin, which is a component of muscle fibres essential for contraction and has a crucial role in numerous cellular processes, such as the formation of lamellipodia and filopodia, as the most abundant component and regulator of cytoskeletons by dynamic assembly and disassembly (from G-actin to F-actin and vice versa). Actin(More)
BACKGROUND KaiA, KaiB and KaiC are cyanobacterial circadian clock proteins. KaiC contains two ATP/GTP-binding Walker's motif As, and mutations in these regions affect the clock oscillations. RESULTS ATP induced the hexamerization of KaiC. The Km value for the ATP for the hexamerization was 1.9 micro m. Triphosphate nucleotides bound to the two Walker's(More)
In bacteria, 70S ribosomes (consisting of 30S and 50S subunits) dimerize to form 100S ribosomes, which were first discovered in Escherichia coli. Ribosome modulation factor (RMF) and hibernation promoting factor (HPF) mediate this dimerization in stationary phase. The 100S ribosome is translationally inactive, but it dissociates into two translationally(More)
The bacterial flagellum is a predominantly cell-external super-macromolecular construction whose structural components are exported by a flagellum-specific export apparatus. One of the export apparatus proteins, FlhB, regulates the substrate specificity of the entire apparatus; i.e. it has a role in the ordered export of the two main groups of flagellar(More)
Construction of the bacterial flagellum in the cell exterior proceeds at its distal end by highly ordered self-assembly of many different component proteins, which are selectively exported through the central channel of the growing flagellum by the flagellar type III export apparatus. FliI is the ATPase of the export apparatus that drives the export(More)
The FliF ring is the base for self-assembly of the bacterial flagellum and the FliF/FliG ring complex is the core of the rotor of the flagellar motor. We report the structures of these two ring complexes obtained by electron cryomicroscopy and single-particle image analysis at 22A and 25A resolution, respectively. Direct comparison of these structures with(More)
The bacterial flagellum and the virulence-associated injectisome are complex, structurally related nanomachines that bacteria use for locomotion or the translocation of virulence factors into eukaryotic host cells. The assembly of both structures and the transfer of extracellular proteins is mediated by a unique, multicomponent transport apparatus, the type(More)
The bacterial flagellum is a motile organelle, and the flagellar hook is a short, highly curved tubular structure that connects the flagellar motor to the long filament acting as a helical propeller. The hook is made of about 120 copies of a single protein, FlgE, and its function as a nano-sized universal joint is essential for dynamic and efficient(More)
The flagellar switch proteins of Salmonella, FliG, FliM and FliN, participate in the switching of motor rotation, torque generation and flagellar assembly/export. FliN has been implicated in the flagellar export process. To address this possibility, we constructed 10-amino-acid scanning deletions and larger truncations over the C-terminal domain of FliN.(More)