2LX9

Solution Structure of Escherichia coli Ferrous Iron transport protein A (FeoA)

Summary for 2LX9

• Entry DOI: 10.2210/pdb2lx9/pdb
• NMR Information: BMRB: 18668
• Descriptor: Ferrous iron transport protein A (1 entity in total)
• Functional Keywords: feoa, transport protein
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 9436.90

Authors

Lau, C.K.Y.,Ishida, H.,Liu, Z.,Vogel, H.J. (deposition date: 2012-08-16, release date: 2012-11-14, Last modification date: 2024-05-15)

Primary citation

Lau, C.K.,Ishida, H.,Liu, Z.,Vogel, H.J.
Solution Structure of Escherichia coli FeoA and Its Potential Role in Bacterial Ferrous Iron Transport.
J.Bacteriol., 195:46-55, 2013

PubMed Abstract: Iron is an indispensable nutrient for most organisms. Ferric iron (Fe(3+)) predominates under aerobic conditions, while during oxygen limitation ferrous (Fe(2+)) iron is usually present. The Feo system is a bacterial ferrous iron transport system first discovered in Escherichia coli K-12. It consists of three genes, feoA, feoB, and feoC (yhgG). FeoB is thought to be the main transmembrane transporter while FeoC is considered to be a transcriptional regulator. Using multidimensional nuclear magnetic resonance (NMR) spectroscopy, we have determined the solution structure of E. coli FeoA. The structure of FeoA reveals a Src-homology 3 (SH3)-like fold. The structure is composed of a β-barrel with two α-helices where one helix is positioned over the barrel. In comparison to the standard eukaryotic SH3 fold, FeoA has two additional α-helices. FeoA was further characterized by heteronuclear NMR dynamics measurements, which suggest that it is a monomeric, stable globular protein. Model-free analysis of the NMR relaxation results indicates that a slow conformational dynamic process is occurring in β-strand 4 that may be important for function. (31)P NMR-based GTPase activity measurements with the N-terminal domain of FeoB (NFeoB) indicate a higher GTP hydrolysis rate in the presence of potassium than with sodium. Further enzymatic assays with NFeoB suggest that FeoA may not act as a GTPase-activating protein as previously proposed. These findings, together with bioinformatics and structural analyses, suggest that FeoA may have a different role, possibly interacting with the cytoplasmic domain of the highly conserved core portion of the FeoB transmembrane region.

PubMed: 23104801
DOI: 10.1128/JB.01121-12

Experimental method

SOLUTION NMR