1d9v
From Proteopedia
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|PDB= 1d9v |SIZE=350|CAPTION= <scene name='initialview01'>1d9v</scene>, resolution 1.75Å | |PDB= 1d9v |SIZE=350|CAPTION= <scene name='initialview01'>1d9v</scene>, resolution 1.75Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=PO4:PHOSPHATE ION'>PO4</scene> | + | |LIGAND= <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= HITA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=727 Haemophilus influenzae]) | |GENE= HITA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=727 Haemophilus influenzae]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1mrp|1MRP]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1d9v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1d9v OCA], [http://www.ebi.ac.uk/pdbsum/1d9v PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1d9v RCSB]</span> | ||
}} | }} | ||
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[[Category: McRee, D E.]] | [[Category: McRee, D E.]] | ||
[[Category: Williams, P A.]] | [[Category: Williams, P A.]] | ||
| - | [[Category: PO4]] | ||
[[Category: abc cassette receptor protein]] | [[Category: abc cassette receptor protein]] | ||
[[Category: apo form]] | [[Category: apo form]] | ||
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[[Category: periplasmic protein]] | [[Category: periplasmic protein]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:37:26 2008'' |
Revision as of 16:37, 30 March 2008
| |||||||
| , resolution 1.75Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Gene: | HITA (Haemophilus influenzae) | ||||||
| Related: | 1MRP
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
HAEMOPHILUS INFLUENZAE FERRIC-BINDING PROTEIN APO FORM
Overview
The crystal structure of the iron-free (apo) form of the Haemophilus influenzae Fe(3+)-binding protein (hFbp) has been determined to 1.75 A resolution. Information from this structure complements that derived from the holo structure with respect to the delineation of the process of iron binding and release. A 21 degrees rotation separates the two structural domains when the apo form is compared with the holo conformer, indicating that upon release of iron, the protein undergoes a change in conformation by bending about the central beta-sheet hinge. A surprising finding in the apo-hFbp structure was that the ternary binding site anion, observed in the crystals as phosphate, remained bound. In solution, apo-hFbp bound phosphate with an affinity K(d) of 2.3 x 10(-3) M. The presence of this ternary binding site anion appears to arrange the C-terminal iron-binding residues conducive to complementary binding to Fe(3+), while residues in the N-terminal binding domain must undergo induced fit to accommodate the Fe(3+) ligand. These observations suggest a binding process, the first step of which is the binding of a synergistic anion such as phosphate to the C-terminal domain. Next, iron binds to the preordered half-site on the C-terminal domain. Finally, the presence of iron organizes the N-terminal half-site and closes the interdomain hinge. The use of the synergistic anion and this iron binding process results in an extremely high affinity of the Fe(3+)-binding proteins for Fe(3+) (nFbp K'(eff) = 2.4 x 10(18) M(-1)). This high-affinity ligand binding process is unique among the family of bacterial periplasmic binding proteins and has interesting implications in the mechanism of iron removal from the Fe(3+)-binding proteins during FbpABC-mediated iron transport across the cytoplasmic membrane.
About this Structure
1D9V is a Single protein structure of sequence from Haemophilus influenzae. Full crystallographic information is available from OCA.
Reference
Crystallographic and biochemical analyses of the metal-free Haemophilus influenzae Fe3+-binding protein., Bruns CM, Anderson DS, Vaughan KG, Williams PA, Nowalk AJ, McRee DE, Mietzner TA, Biochemistry. 2001 Dec 25;40(51):15631-7. PMID:11747438
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