title: Helicobacter pylori HP0518 affects flagellin glycosylation to alter bacterial motility.
abstract: Helicobacter pylori is a human gastric pathogen associated with gastric and duodenal ulcers as well as gastric cancer. Mounting evidence suggests this pathogen's motility is prerequisite for successful colonization of human gastric tissues. Here, we isolated an H. pylori G27 HP0518 mutant exhibiting altered motility in comparison to its parental strain. We show that the mutant's modulated motility is linked to increased levels of O-linked glycosylation on flagellin A (FlaA) protein. Recombinant HP0518 protein decreased glycosylation levels of H. pylori flagellin in vitro, indicating that HP0518 functions in deglycosylation of FlaA protein. Furthermore, mass spectrometric analysis revealed increased glycosylation of HP0518 FlaA was due to a change in pseudaminic acid (Pse) levels on FlaA; HP0518 mutant-derived flagellin contained approximately threefold more Pse than the parental strain. Further phenotypic and molecular characterization demonstrated that the hyper-motile HP0518 mutant exhibits superior colonization capabilities and subsequently triggers enhanced CagA phosphorylation and NF-κB activation in AGS cells. Our study shows that HP0518 is involved in the deglycosylation of flagellin, thereby regulating pathogen motility. These findings corroborate the prominent function of H. pylori flagella in pathogen-host cell interactions and modulation of host cell responses, likely influencing the pathogenesis process.
authors.affiliation: Department of Molecular Biology and Core Facilities for Genomics, Max Planck Institute for Infection Biology, Cháriteplatz 1, Campus Chárite, 10117 Berlin, Germany.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Asakura
authors.forename: Yuri
authors.initials: Y
authors.lastname: Churin
authors.forename: Bianca
authors.initials: B
authors.lastname: Bauer
authors.forename: Jan Peter
authors.initials: JP
authors.lastname: Boettcher
authors.forename: Sina
authors.initials: S
authors.lastname: Bartfeld
authors.forename: Noritaka
authors.initials: N
authors.lastname: Hashii
authors.forename: Nana
authors.initials: N
authors.lastname: Kawasaki
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Mollenkopf
authors.forename: Peter R
authors.initials: PR
authors.lastname: Jungblut
authors.forename: Volker
authors.initials: V
authors.lastname: Brinkmann
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Meyer
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D005260:Female; D005408:Flagellin / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D006031:Glycosylation; D016481:Helicobacter Infections / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics / Q000502:physiology*; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: D001426:Bacterial Proteins; C556382:HP0518 protein, Helicobacter pylori; D005408:Flagellin