The Crystal Structure of Ferritin from Helicobacter pylori Reveals Unusual Conformational Changes for Iron Uptake

Ki Joon Cho, Hye Jeong Shin, Ji Hye Lee, Kyung Jin Kim, Sarah S. Park, Youngmi Lee, Cheolju Lee, Sung Soo Park, Kyung Hyun Kim

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

The crystal structure of recombinant ferritin from Helicobacter pylori has been determined in its apo, low-iron-bound, intermediate, and high-iron-bound states. Similar to other members of the ferritin family, the bacterial ferritin assembles as a spherical protein shell of 24 subunits, each of which folds into a four-α-helix bundle. Significant conformational changes were observed at the BC loop and the entrance of the 4-fold symmetry channel in the intermediate and high-iron-bound states, whereas no change was found in the apo and low-iron-bound states. The imidazole rings of His149 at the channel entrance undergo conformational changes that bear resemblance to heme configuration and are directly coupled to axial translocation of Fe ions through the 4-fold channel. Our results provide the first structural evidence of the translocation of Fe ions through the 4-fold channel in prokaryotes and the transition from a protein-dominated process to a mineral-surface-dominated process during biomineralization.

Original languageEnglish
Pages (from-to)83-98
Number of pages16
JournalJournal of Molecular Biology
Volume390
Issue number1
DOIs
Publication statusPublished - 2009 Jul 3

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Keywords

  • 4-fold channel
  • biomineralization
  • ferritin
  • Helicobacter pylori
  • iron uptake mechanism

ASJC Scopus subject areas

  • Molecular Biology

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