FliK-Driven Conformational Rearrangements of FlhA and FlhB Are Required for Export Switching of the Flagellar Protein Export Apparatus.

ABSTRACT: FlhA and FlhB are transmembrane proteins of the flagellar type III protein export apparatus, and their C-terminal cytoplasmic domains (FlhA_C and FlhB_C) coordinate flagellar protein export with assembly. FlhB_C undergoes autocleavage between Asn-269 and Pro-270 in a well-conserved NPTH loop located between FlhB_CN and FlhB_CC polypeptides and interacts with the C-terminal domain of the FliK ruler when the length of the hook has reached about 55 nm in Salmonella As a result, the flagellar protein export apparatus switches its substrate specificity, thereby terminating hook assembly and initiating filament assembly. The mechanism of export switching remains unclear. Here, we report the role of FlhB_C cleavage in the switchin

SUBMITTER: Minamino T 

PROVIDER: S-EPMC6964733 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature