Flagellinolysin is a variant form of bacterial flagellin in with the normally hypervariable central region contains an M9 (MEROPS classification) family metalloprotease domain, with its signature HExxH motif. The founding member of the family, from the pathogen Clostridium haemolyticum, shows EDTA-sensitive metalloprotease activity. The large count of flagellin subunits in a complete flagellum means the capacity of flagellinolysin to perform as a protease may have implications for host-pathogen relationships.
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