Helicobacter pylori Flagellar Hook-Filament Transition Is Controlled by a FliK Functional Homolog Encoded by the Gene HP0906

Abstract

Volume 187, no. 16, p. 5742-5750, 2005. Attempts to extend the observation of complementation of a Salmonella fliK mutant by HP0906 to orthologous genes led to the discovery that the apparent restoration of motility by expression of HP0906 in the Salmonella fliK mutant strain SJW108 was actually due to reversion of the fliK mutation. This reversion occurred in the transformant with the pQE60-HP0906 construct. Expression of HP0906 does not complement Salmonella fliK, and the apparent motility in Fig. 7C (labeled SJW108/pQE60-HP0906) is incorrect. The bioinformatic, ultrastructural, motility, and regulatory data identifying HP0906 as fliK are unaffected, and the main conclusion remains unchanged. 6046on May 9, 2018 by guest

MotD of Sinorhizobium meliloti and Related α-Proteobacteria Is the Flagellar-Hook-Length Regulator and Therefore Reassigned as FliK

“…The primary function of FliK, together with a transmembrane protein of the export apparatus, FlhB, is to regulate the length of the flagellar hook. However, the occurrence of polyhook mutants has been reported for only a small number of bacterial species, including the soil bacterium Rhizobium lupini (10,25,35,36,46).…”

Posttranscriptional Regulation of Flagellin Synthesis in Helicobacter pylori by the RpoN Chaperone HP0958

“…H. pylori strains were cultured as previously described (49). A CCUG17874-derivative H. pylori mutant lacking the HP0958 gene was previously described (48,49). The P79 strain-derivative H. pylori mutant lacking the HP0958 gene was generated as previously described by Ryan et al for strain CCUG17874 (48).…”

“…H. pylori strain P79 (33), a streptomycin mutant of the P1 wild-type strain, was generously provided by R. Haas. H. pylori strains were cultured as previously described (49). A CCUG17874-derivative H. pylori mutant lacking the HP0958 gene was previously described (48,49).…”

“…This repression is relieved when FlgM is secreted from the cell upon completion of the hook structure (29), though FlgM secretion has not actually been demonstrated for H. pylori. The hook length is under the control of FliK in Salmonella (15), which we recently identified as the product of the gene HP0906 in H. pylori (49). Completion of the hook structure modulates the activity of the RpoN regulon in H. pylori.…”

Helicobacter pylori FlhB Function: the FlhB C-Terminal Homologue HP1575 Acts as a “Spare Part” To Permit Flagellar Export When the HP0770 FlhB CC Domain Is Deleted

“…It has been proposed that the function of this processing, which generates two proteins, the FlhB fragment containing the transmembrane helices and the N-terminal part of the C-terminal domain (FlhB TMϩCN ) and the FlhB fragment containing the CC domain (FlhB CC ), is to change the substrate specificity for flagellar export from rod-and hook-type proteins to filamenttype proteins (10). In Salmonella the function of FlhB requires interaction of the cleaved FlhB CC domain with the hook length control protein FliK (13,24), a functional homologue of which has recently been identified in H. pylori (32). Cleavage has also been investigated in Yersinia pseudotuberculosis where YscU, a FlhB homologue which is part of a type III secretion system, is cleaved between Asn 263 and Pro 264 (16).…”