title: Helicobacter pylori HP0876 is dispensable for heme-iron acquisition but attenuates bacterial adherence to gastric epithelial cells.
abstract: Helicobacter pylori can efficiently capture iron either from free heme or heme-containing compounds in the iron-limited gastric mucosa. However, the heme iron utilization systems of H. pylori have not been fully described to date. To investigate the contribution of genes involved in heme-iron utilization, a gene homologous to frpB, encode by hp0876 in H. pylori ATCC 26695, was inactivated by homologous recombination. Δhp0876 showed no demonstrable growth defects in the presence of the various concentrations of free iron. Moreover, when hemoglobin or heme was supplied as the sole iron sources, Δhp0876 had growth curves similar to the wild-type strain. The growth competition experiments in vitro also showed that Δhp0876 retained the ability for iron acquisition. Furthermore, IL-8 production in human gastric epithelial cells co-cultured with Δhp0876 and wild-type strain was compared, and our results indicated that lack of HP0876 affected the IL-8 release. And Δhp0876 exhibited significantly increased adherence to gastric epithelial cells. Together, our data suggests that HP0876 is dispensable for H. pylori heme-iron uptake, but it may attenuate H. pylori adherence to gastric epithelial cells, which induced decreased production of H. pylori-induced IL-8 production in gastric epithelial cells.
authors: Department of Clinical Microbiology and Immunology, College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, China. cedarliu@foxmail.com
authors: Tao
authors: T
authors: Liu
authors: Yun
authors: Y
authors: Shi
authors: Xiao-fei
authors: XF
authors: Liu
authors: Ying
authors: Y
authors: Guo
authors: Xu-hu
authors: XH
authors: Mao
authors: Che
authors: C
authors: Tan
authors: Yuan
authors: Y
authors: Zhuang
authors: Liu-sheng
authors: LS
authors: Peng
authors: Jin-yu
authors: JY
authors: Zhang
authors: Quan-ming
authors: QM
authors: Zou
mesh_terms: D001422:Bacterial Adhesion / Q000235:genetics / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D015169:Colony Count, Microbial; D004847:Epithelial Cells / Q000166:cytology / Q000382:microbiology; D005753:Gastric Mucosa / Q000166:cytology / Q000382:microbiology*; D055786:Gene Knockout Techniques; D016480:Helicobacter pylori / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D006418:Heme / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D001425:Bacterial Outer Membrane Proteins; C093120:FrpB protein, bacteria; D006418:Heme; D007501:Iron