title: Histidine-rich protein Hpn from Helicobacter pylori forms amyloid-like fibrils in vitro and inhibits the proliferation of gastric epithelial AGS cells.
abstract: Helicobacter pylori causes various gastric diseases, such as gastritis, peptic ulcerations, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Hpn is a histidine-rich protein abundant in this bacterium and forms oligomers in physiologically relevant conditions. In this present study, Hpn oligomers were found to develop amyloid-like fibrils as confirmed by negative stain transition electron microscopy, thioflavin T and Congo red binding assays. The amyloid-like fibrils of Hpn inhibit the proliferation of gastric epithelial AGS cells through cell cycle arrest in the G2/M phase, which may be closely related to the disruption of mitochondrial bioenergetics as reflected by the significant depletion of intracellular ATP levels and the mitochondrial membrane potential. The collective data presented here shed some light on the pathologic mechanisms of H. pylori infections.
authors.affiliation: The laboratory of Integrative Biosciences, College of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China. gerg@mail.sysu.edu.cn
authors.forename: Ruiguang
authors.initials: R
authors.lastname: Ge
authors.forename: Xuesong
authors.initials: X
authors.lastname: Sun
authors.forename: Dongxian
authors.initials: D
authors.lastname: Wang
authors.forename: Qinglu
authors.initials: Q
authors.lastname: Zhou
authors.forename: Hongzhe
authors.initials: H
authors.lastname: Sun
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000502:physiology* / Q000648:ultrastructure; D002460:Cell Line; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000382:microbiology / Q000473:pathology; D005753:Gastric Mucosa / Q000382:microbiology* / Q000473:pathology*; D016481:Helicobacter Infections / Q000209:etiology; D016480:Helicobacter pylori / Q000472:pathogenicity* / Q000502:physiology*; D006801:Humans; D053078:Membrane Potential, Mitochondrial; D046529:Microscopy, Electron, Transmission; D055503:Protein Multimerization; D011506:Proteins / Q000737:chemistry* / Q000502:physiology* / Q000648:ultrastructure; D000099053:Histidine-Rich Glycoprotein
chemical_list: D001426:Bacterial Proteins; D011506:Proteins; D000099053:Histidine-Rich Glycoprotein; D000255:Adenosine Triphosphate