The neuA/flmD gene cluster of Helicobacter pylori is involved in flagellar biosynthesis and flagellin glycosylation.
Helicobacter pylori possesses a gene (HP0326/JHP309) homologous to neuA of other bacteria, encoding a cytidyl monophosphate-N-acetylneuraminic acid synthetase-homologous enzyme in its N-terminal portion. We analysed the function of this gene, which is controlled by a flagellar class 2 sigma(54) promoter, in flagellar biosynthesis. HP0326/JHP309 actually represents a bicistronic operon consisting of a neuA and a flmD-like putative glycosyl transferase gene. An isogenic flmD mutant synthesized basal bodies but no filaments, was non-motile, and expressed severely reduced amounts of a FlaA flagellin of reduced molecular mass. FlaA flagellin was found to be glycosylated in its exported form within the flagellar filament, but not inside the cytoplasm. Glycosylated FlaA was not detectable in the flmD mutant. Together with other genes in the H. pylori genome, a proposed function of the neuA/flmD gene products could be to provide a pathway for glycosylation of flagellin and other extracytoplasmic molecules during type III secretion.
Josenhans
Christine
C
Institut für Hygiene und Mikrobiologie der Universität Würzburg, Josef-Schneider-Strasse 2, D-97080 Würzburg, Germany. cjosenhans@hygiene.uni-wuerzburg.de
Vossebein
Lutz
L
Friedrich
Susanne
S
Suerbaum
Sebastian
S
D015153:Blotting, Western; D004268:DNA-Binding Proteins; D012321:DNA-Directed RNA Polymerases; D005407:Flagella / Q000737:chemistry* / Q000378:metabolism* / Q000648:ultrastructure; D005408:Flagellin / Q000737:chemistry / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics*; D005816:Genetic Complementation Test; D006031:Glycosylation; D016480:Helicobacter pylori / Q000166:cytology* / Q000235:genetics* / Q000648:ultrastructure; D008124:Locomotion; D008970:Molecular Weight; D005810:Multigene Family / Q000235:genetics*; D016296:Mutagenesis; D009154:Mutation; D009876:Operon / Q000235:genetics; D010641:Phenotype; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D051877:RNA Polymerase Sigma 54; D012808:Sigma Factor
D004268:DNA-Binding Proteins; D011135:Polysaccharides, Bacterial; D012808:Sigma Factor; D005408:Flagellin; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54