title: Studies on the X-Ray and Solution Structure of FeoB from Escherichia coli BL21.
abstract: The ferrous iron transporter FeoB is an important factor in the iron metabolism of many bacteria. Although several structural studies have been performed on its cytosolic GTPase domain (NFeoB), the full-length structure of FeoB remains elusive. Based on a crystal packing analysis that was performed on crystals of NFeoB, a trimeric structure of the FeoB channel was proposed, where the transport pore runs along the trimer axis. Because this trimer has not been observed in some subsequently solved structures of NFeoB homologs, it remains unclear whether or not the trimer is indeed functionally relevant. Here, pulsed electron-electron double resonance spectroscopy, negative stain electron microscopy, and native mass spectrometry are used to analyze the oligomeric state of different soluble and full-length FeoB constructs. The results show that the full-length protein is predominantly monomeric, whereas dimers and trimers are formed to a small percentage. Furthermore, the solution structure of the switch I region is analyzed by pulsed electron-electron double resonance spectroscopy and a new, to our knowledge, crystal structure of NFeoB from Escherichia coli BL21 is presented.
authors.affiliation: Institute for Physical and Theoretical Chemistry,University of Bonn, Bonn, Germany. Electronic address: hagelueken@pc.uni-bonn.de.
authors.forename: Gregor
authors.initials: G
authors.lastname: Hagelueken
authors.affiliation: Institute for Physical and Theoretical Chemistry, Goethe-University Frankfurt, Frankfurt, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Hoffmann
authors.affiliation: Institute for Physical and Theoretical Chemistry,University of Bonn, Bonn, Germany.
authors.forename: Erik
authors.initials: E
authors.lastname: Schubert
authors.affiliation: Institute for Physical and Theoretical Chemistry,University of Bonn, Bonn, Germany.
authors.forename: Fraser G
authors.initials: FG
authors.lastname: Duthie
authors.affiliation: Institute for Physical and Theoretical Chemistry,University of Bonn, Bonn, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Florin
authors.affiliation: Institute for Physical and Theoretical Chemistry,University of Bonn, Bonn, Germany.
authors.forename: Lisa
authors.initials: L
authors.lastname: Konrad
authors.affiliation: Pharmaceutical Chemistry I, Pharmaceutical Institute, University of Bonn, Bonn, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: Imhof
authors.affiliation: Research Group Structural Dynamics of Proteins, Center of Advanced European Studes and Research (CAESAR), Bonn, Germany.
authors.forename: Elmar
authors.initials: E
authors.lastname: Behrmann
authors.affiliation: Institute for Physical and Theoretical Chemistry, Goethe-University Frankfurt, Frankfurt, Germany.
authors.forename: Nina
authors.initials: N
authors.lastname: Morgner
authors.affiliation: Institute for Physical and Theoretical Chemistry,University of Bonn, Bonn, Germany.
authors.forename: Olav
authors.initials: O
authors.lastname: Schiemann
mesh_terms: D027682:Cation Transport Proteins / Q000737:chemistry*; D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000737:chemistry*; D013058:Mass Spectrometry; D064347:Microscopy, Electrochemical, Scanning; D000072417:Protein Domains; D055503:Protein Multimerization; D012996:Solutions
chemical_list: D027682:Cation Transport Proteins; D029968:Escherichia coli Proteins; C470580:FeoB protein, E coli; D012996:Solutions