1Y9U

Bordetella ferric binding protein

Summary for 1Y9U

• Entry DOI: 10.2210/pdb1y9u/pdb
• Descriptor: putative iron binding protein (2 entities in total)
• Functional Keywords: periplasmic binding protein, iron tyrosinate interaction, metal binding protein
• Biological source: Bordetella pertussis Tohama I
• Total number of polymer chains: 1
• Total formula weight: 34821.57

Authors

Tom-Yew, S.A.L.,Cui, D.T.,Bekker, E.G.,Murphy, M.E.P. (deposition date: 2004-12-16, release date: 2005-01-11, Last modification date: 2024-10-30)

Primary citation

Tom-Yew, S.A.L.,Cui, D.T.,Bekker, E.G.,Murphy, M.E.P.
Anion-independent iron coordination by the Campylobacter jejuni ferric binding protein
J.Biol.Chem., 280:9283-9290, 2005

PubMed Abstract: Campylobacter jejuni, the leading cause of human gastroenteritis, expresses a ferric binding protein (cFbpA) that in many pathogenic bacteria functions to acquire iron as part of their virulence repertoire. Recombinant cFbpA is isolated with ferric iron bound from Escherichia coli. The crystal structure of cFbpA reveals unprecedented iron coordination by only five protein ligands. The histidine and one tyrosine are derived from the N-terminal domain, whereas the three remaining tyrosine ligands are from the C-terminal domain. Surprisingly, a synergistic anion present in all other characterized ferric transport proteins is not observed in the cFbpA iron-binding site, suggesting a novel role for this protein in iron uptake. Furthermore, cFbpA is shown to bind iron with high affinity similar to Neisserial FbpA and exhibits an unusual preference for ferrous iron (oxidized subsequently to the ferric form) or ferric iron chelated by oxalate. Sequence and structure analyses reveal that cFbpA is a member of a new class of ferric binding proteins that includes homologs from invasive and intracellular bacteria as well as cyanobacteria. Overall, six classes are defined based on clustering within the tree and by their putative iron coordination. The absence of a synergistic anion in the iron coordination sphere of cFbpA also suggests an alternative model of evolution for FbpA homologs involving an early iron-binding ancestor instead of a requirement for a preexisting anion-binding ancestor.

PubMed: 15613474
DOI: 10.1074/jbc.M412479200

Experimental method

X-RAY DIFFRACTION (1.39 Å)