The protein BSU35380 from Bacillus subtilis (renamed FliW) was characterised as being a flagellar assembly factor. Experimental characterisation was also carried out in Treponema pallidum (TP0658). In Campylobacter jejuni, Cj1075 has been shown to be involved in motility and flagellin biosynthesis. The two paralogues in Helicobacter pylori (HP1154 and HP1377) were found to be able to bind to flagellin. FliW proteins are involved in flagellar assembly [4]. FliW is part of a three-part feedback loop: in Bacillus subtilis FliW inhibits CsrA (an RNA-binding protein) which inhibits FliC translation; hence FliW is required for FliC (flagellin) production [5].

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4: CsrA of Bacillus subtilis regulates translation initiation of the gene encoding the flagellin protein (hag) by blocking ribosome binding. Yakhnin H, Pandit P, Petty TJ, Baker CS, Romeo T, Babitzke P; Mol Microbiol. 2007;64:1605-1620. PMID:17555441

5: CsrA-FliW interaction governs flagellin homeostasis and a checkpoint on flagellar morphogenesis in Bacillus subtilis. Mukherjee S, Yakhnin H, Kysela D, Sokoloski J, Babitzke P, Kearns DB; Mol Microbiol. 2011;82:447-461. PMID:21895793