An Overview of Helicobacter pylori VacA Toxin Biology.
The VacA toxin secreted by Helicobacter pylori enhances the ability of the bacteria to colonize the stomach and contributes to the pathogenesis of gastric adenocarcinoma and peptic ulcer disease. The amino acid sequence and structure of VacA are unrelated to corresponding features of other known bacterial toxins. VacA is classified as a pore-forming toxin, and many of its effects on host cells are attributed to formation of channels in intracellular sites. The most extensively studied VacA activity is its capacity to stimulate vacuole formation, but the toxin has many additional effects on host cells. Multiple cell types are susceptible to VacA, including gastric epithelial cells, parietal cells, T cells, and other types of immune cells. This review focuses on the wide range of VacA actions that are detectable in vitro, as well as actions of VacA in vivo that are relevant for H. pylori colonization of the stomach and development of gastric disease.
Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. nora.j.foegeding@vanderbilt.edu.
Nora J
NJ
Foegeding
Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. rhonda.r.caston@vanderbilt.edu.
Rhonda R
RR
Caston
Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. mark.s.mcclain@vanderbilt.edu.
Mark S
MS
McClain
Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. melanie.ohi@vanderbilt.edu.|Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA. melanie.ohi@vanderbilt.edu.
Melanie D
MD
Ohi
Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. timothy.L.cover@vanderbilt.edu.|Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. timothy.L.cover@vanderbilt.edu.|Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA. timothy.L.cover@vanderbilt.edu.
Timothy L
TL
Cover
D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000633:toxicity; D001427:Bacterial Toxins / Q000737:chemistry / Q000235:genetics / Q000633:toxicity; D016480:Helicobacter pylori / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007473:Ion Channels / Q000378:metabolism; D011487:Protein Conformation; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D007473:Ion Channels; C074689:VacA protein, Helicobacter pylori
autotransporter; bacterial toxins; gastric cancer; type V secretion; vacuolating toxin