7U37

Solution NMR structure of Vibrio cholerae ferrous iron transport protein C (FeoC)

Summary for 7U37

• Entry DOI: 10.2210/pdb7u37/pdb
• NMR Information: BMRB: 30995
• Descriptor: Ferrous iron transport protein C (1 entity in total)
• Functional Keywords: feoc, ferrous iron transport, feo, cytosolic protein
• Biological source: Vibrio cholerae O1
• Total number of polymer chains: 1
• Total formula weight: 8590.94

Authors

Brown, J.B.,Lee, M.A.,Smith, A.T. (deposition date: 2022-02-25, release date: 2022-07-13, Last modification date: 2024-05-15)

Primary citation

Brown, J.B.,Lee, M.A.,Smith, A.T.
The structure of Vibrio cholerae FeoC reveals conservation of the helix-turn-helix motif but not the cluster-binding domain.
J.Biol.Inorg.Chem., 27:485-495, 2022

PubMed Abstract: Most pathogenic bacteria require ferrous iron (Fe) in order to sustain infection within hosts. The ferrous iron transport (Feo) system is the most highly conserved prokaryotic transporter of Fe, but its mechanism remains to be fully characterized. Most Feo systems are composed of two proteins: FeoA, a soluble SH3-like accessory protein, and FeoB, a membrane protein that translocates Fe across a lipid bilayer. Some bacterial feo operons encode FeoC, a third soluble, winged-helix protein that remains enigmatic in function. We previously demonstrated that selected FeoC proteins bind O-sensitive [4Fe-4S] clusters via Cys residues, leading to the proposal that some FeoCs could sense O to regulate Fe transport. However, not all FeoCs conserve these Cys residues, and FeoC from the causative agent of cholera (Vibrio cholerae) notably lacks any Cys residues, precluding cluster binding. In this work, we determined the NMR structure of VcFeoC, which is monomeric and conserves the helix-turn-helix domain seen in other FeoCs. In contrast, however, the structure of VcFeoC reveals a truncated winged β-sheet in which the cluster-binding domain is notably absent. Using homology modeling, we predicted the structure of VcNFeoB and used docking to identify an interaction site with VcFeoC, which is confirmed by NMR spectroscopy. These findings provide the first atomic-level structure of VcFeoC and contribute to a better understanding of its role vis-à-vis FeoB.

PubMed: 35796835
DOI: 10.1007/s00775-022-01945-4

Experimental method

SOLUTION NMR