Organization of the Flagellar Switch Complex of Bacillus subtilis

• DOI: 10.1128/jb.00626-18
• Publication Date: 2018-11-20T13:55:04Z
• Authors: Elizabeth Ward; Eun A Kim; Joseph Panushka; Tayson Botelho; Trevor Meyer; Daniel B. Kearns; George Ordal; David F. Blair
• Keywords: Bacillus (shape)

While the protein complex responsible for controlling direction (clockwise [CW] or counterclockwise [CCW]) of flagellar rotation has been fairly well studied in Escherichia coli and Salmonella, less is known about switch Bacillus subtilis other Gram-positive species. Two component proteins (FliG FliM) are shared between E. B. subtilis, but place FliN found coli, contains larger FliY. Notably, signaling CheY-phosphate induces a from CW to CCW rotation, opposite its action Here, we have examined architecture function using targeted cross-linking, bacterial two-hybrid interaction experiments, characterization mutant phenotypes. In major respects, appears be organized similarly that The around ring built large middle domain FliM; this supports an array FliG subunits similar way with C-terminal functioning generation torque via conserved charged residues. Key differences involve FliY, which forms additional, more outboard array, domains FliM into both FliY homodimers heterodimers. Together, results suggest conformational states Gram-negative switches drives oppositely directed movements two cases.IMPORTANCE Flagellar motility plays key roles survival many bacteria harmful pathogens. Bacterial flagella rotate; controlled by multisubunit termed complex. This extensively model species, little species responds effector (CheY-P) switching whereas Salmonella CheY-P acts way, promoting rotation. work here, probed measurements, mutational approaches. cast light on organization provide framework understanding mechanism control