5XBJ

The structure of the flagellar hook junction protein HAP1 (FlgK) from Campylobacter jejuni

Summary for 5XBJ

• Entry DOI: 10.2210/pdb5xbj/pdb
• Descriptor: Flagellar hook-associated protein FlgK (2 entities in total)
• Functional Keywords: bacterial flagellum, hook, filament, junction protein, biosynthetic protein
• Biological source: Campylobacter jejuni
• Total number of polymer chains: 1
• Total formula weight: 56983.16

Authors

Samatey, F.A. (deposition date: 2017-03-19, release date: 2017-12-06, Last modification date: 2023-11-22)

Primary citation

Bulieris, P.V.,Shaikh, N.H.,Freddolino, P.L.,Samatey, F.A.
Structure of FlgK reveals the divergence of the bacterial Hook-Filament Junction of Campylobacter
Sci Rep, 7:15743-15743, 2017

PubMed Abstract: Evolution of a nano-machine consisting of multiple parts, each with a specific function, is a complex process. A change in one part should eventually result in changes in other parts, if the overall function is to be conserved. In bacterial flagella, the filament and the hook have distinct functions and their respective proteins, FliC and FlgE, have different three-dimensional structures. The filament functions as a helical propeller and the hook as a flexible universal joint. Two proteins, FlgK and FlgL, assure a smooth connectivity between the hook and the filament. Here we show that, in Campylobacter, the 3D structure of FlgK differs from that of its orthologs in Salmonella and Burkholderia, whose structures have previously been solved. Docking the model of the FlgK junction onto the structure of the Campylobacter hook provides some clues about its divergence. These data suggest how evolutionary pressure to adapt to structural constraints, due to the structure of Campylobacter hook, causes divergence of one element of a supra-molecular complex in order to maintain the function of the entire flagellar assembly.

PubMed: 29147015
DOI: 10.1038/s41598-017-15837-0

Experimental method

X-RAY DIFFRACTION (2.448 Å)