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The Bacterial Flagellar Hook
From Proteopedia
The bacterial flagellar hook described in this article is one part of the bacterial flagellum. Please see Flagella, bacterial (under development at Sandbox4 Eric Martz for an overview of where the hook fits in the flagellum.
The flagellar hook is a molecular universal joint that transmits torque from the motor, anchored in the bacterial cell wall, to the flagellar filament, the relatively rigid helical rod that propels the bacterial cell when rotated. The hook is flexible: it enables the filament to adopt a wide range of angles relative to the motor axis and cell wall, yet continue to be rotated by the motor at all these angles.
Structure of the Hook Monomer, FlgE
The hook is composed of about 120 copies of the protein chain FlgE (the product of the gene flgE). In 2004, Samatey et al. solved the structure of the mid-portion of the wild-type FlgE of Salmonella typhimurium by X-ray crystallography at a resolution of 1.8 Å[1].
Content Attribution
The initial content for this article was adapted, with permission, from The Bacterial Flagellar Hook: A Molecular Universal Joint, authored by User:Eric Martz in 2004-2006 for Protein Explorer.
