Crystal Structure of Haemophilus influenzae N193L mutant FbpACrystal Structure of Haemophilus influenzae N193L mutant FbpA

Structural highlights

2o69 is a 1 chain structure with sequence from Haemophilus influenzae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 2Å
Ligands:
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

FBPA_HAEIN Part of the ABC transporter complex FbpABC (TC 3.A.1.10.1) involved in Fe(3+) ions import. This protein specifically binds Fe(3+) and is involved in its transmembrane transport (By similarity).

Evolutionary Conservation

 

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The acquisition of iron from transferrin by Gram-negative bacterial pathogens is dependent on a periplasmic ferric-ion-binding protein, FbpA. FbpA shuttles iron from the outer membrane to an inner membrane transport complex. A bound phosphate anion completes the iron co-ordination shell of FbpA and kinetic studies demonstrate that the anion plays a critical role in iron binding and release in vitro. The present study was initiated to directly address the hypothesis that the synergistic anion is required for transport of iron in intact cells. A series of site-directed mutants in the anion-binding amino acids of the Haemophilus influenzae FbpA (Gln-58, Asn-175 and Asn-193) were prepared to provide proteins defective in binding of the phosphate anion. Crystal structures of various mutants have revealed that alteration of the C-terminal domain ligands (Asn-175 or Asn-193) but not the N-terminal domain ligand (Gln-58) abrogated binding of the phosphate anion. The mutant proteins were introduced into H. influenzae to evaluate their ability to mediate iron transport. All of the single site-directed mutants (Q58L, N175L and N193L) were capable of mediating iron acquisition from transferrin and from limiting concentrations of ferric citrate. The results suggest that the transport of iron by FbpA is not dependent on binding of phosphate in the synergistic anion-binding site.

The role of the synergistic phosphate anion in iron transport by the periplasmic iron-binding protein from Haemophilus influenzae.,Khan AG, Shouldice SR, Tari LW, Schryvers AB Biochem J. 2007 Apr 1;403(1):43-8. PMID:17147516[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Khan AG, Shouldice SR, Tari LW, Schryvers AB. The role of the synergistic phosphate anion in iron transport by the periplasmic iron-binding protein from Haemophilus influenzae. Biochem J. 2007 Apr 1;403(1):43-8. PMID:17147516 doi:http://dx.doi.org/10.1042/BJ20061589

2o69, resolution 2.00Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA