The VacA toxin of Helicobacter pylori identifies a new intermediate filament-interacting protein

EMBO J. 2000 Jan 4;19(1):48-56. doi: 10.1093/emboj/19.1.48.


The VacA toxin produced by Helicobacter pylori acts inside cells and induces the formation of vacuoles arising from late endosomal/lysosomal compartments. Using VacA as bait in a yeast two-hybrid screening of a HeLa cell library, we have identified a novel protein of 54 kDa (VIP54), which interacts specifically with VacA, as indicated by co-immunoprecipitation and binding experiments. VIP54 is expressed in cultured cells and many tissues, with higher expression in the brain, muscle, kidney and liver. Confocal immunofluorescence microscopy with anti-VIP54 affinity- purified antibodies shows a fibrous pattern typical of intermediate filaments. Double label immunofluorescence performed on various cell lines with antibodies specific to different intermediate filament proteins revealed that VIP54 largely co-distributes with vimentin. In contrast to known intermediate filament proteins, VIP54 is predicted to contain approximately 50% of helical segments, but no extended coiled-coil regions. The possible involvement of this novel protein in interactions between intermediate filaments and late endosomal compartments is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Astrocytes / chemistry
  • Bacterial Proteins / metabolism*
  • Bacterial Toxins / metabolism*
  • Cell Line
  • Cytotoxins / metabolism
  • Dogs
  • HeLa Cells
  • Helicobacter pylori / metabolism*
  • Humans
  • Intermediate Filament Proteins / immunology
  • Intermediate Filament Proteins / isolation & purification*
  • Intermediate Filament Proteins / metabolism
  • Mice
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Molecular Weight
  • Neuroblastoma / chemistry
  • Neurons / chemistry
  • Tumor Cells, Cultured
  • Vacuoles / metabolism
  • Vimentin / isolation & purification


  • Bacterial Proteins
  • Bacterial Toxins
  • Cytotoxins
  • Intermediate Filament Proteins
  • VIP54 protein, Helicobacter pylori
  • VacA protein, Helicobacter pylori
  • Vimentin

Associated data

  • GENBANK/AA840455
  • GENBANK/AC007439
  • GENBANK/AI158261
  • GENBANK/AJ242655