Open AccessStructure of an atypical FeoB G‐domain reveals a putative domain‐swapped dimer
Author(s) -
Deshpande Chandrika N.,
McGrath Aaron P.,
Font Josep,
Guilfoyle Amy P.,
Maher Megan J.,
Jormakka Mika
Publication year - 2013
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309113005939
Subject(s) - transmembrane domain , dimer , domain (mathematical analysis) , hamp domain , gtpase , transmembrane protein , cytoplasm , protein domain , protein structure , biophysics , transport protein , cyclic nucleotide binding domain , biology , egf like domain , crystallography , chemistry , biochemistry , peptide sequence , amino acid , gene , receptor , mathematical analysis , mathematics , organic chemistry
FeoB is a transmembrane protein involved in ferrous iron uptake in prokaryotic organisms. FeoB comprises a cytoplasmic soluble domain termed NFeoB and a C‐terminal polytopic transmembrane domain. Recent structures of NFeoB have revealed two structural subdomains: a canonical GTPase domain and a five‐helix helical domain. The GTPase domain hydrolyses GTP to GDP through a well characterized mechanism, a process which is required for Fe 2+ transport. In contrast, the precise role of the helical domain has not yet been fully determined. Here, the structure of the cytoplasmic domain of FeoB from Gallionella capsiferriformans is reported. Unlike recent structures of NFeoB, the G. capsiferriformans NFeoB structure is highly unusual in that it does not contain a helical domain. The crystal structures of both apo and GDP‐bound protein forms a domain‐swapped dimer.