Structural basis of GDP release and gating in G protein coupled Fe2+ transport Academic Article uri icon


  • G proteins are key molecular switches in the regulation of membrane protein function and signal transduction. The prokaryotic membrane protein FeoB is involved in G protein coupled Fe(2+) transport, and is unique in that the G protein is directly tethered to the membrane domain. Here, we report the structure of the soluble domain of FeoB, including the G protein domain, and its assembly into an unexpected trimer. Comparisons between nucleotide free and liganded structures reveal the closed and open state of a central cytoplasmic pore, respectively. In addition, these data provide the first observation of a conformational switch in the nucleotide-binding G5 motif, defining the structural basis for GDP release. From these results, structural parallels are drawn to eukaryotic G protein coupled membrane processes.


  • Guilfoyle, Amy
  • Maher, Megan J
  • Rapp, Mikaela
  • Clarke, Ronald
  • Harrop, Stephen
  • Jormakka, Mika

publication date

  • September 2, 2009