1qi9
From Proteopedia
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|PDB= 1qi9 |SIZE=350|CAPTION= <scene name='initialview01'>1qi9</scene>, resolution 2.05Å | |PDB= 1qi9 |SIZE=350|CAPTION= <scene name='initialview01'>1qi9</scene>, resolution 2.05Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=IOD:IODIDE+ION'>IOD</scene>, <scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene>, <scene name='pdbligand=VO4:VANADATE+ION'>VO4</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Chloride_peroxidase Chloride peroxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.11.1.10 1.11.1.10] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Chloride_peroxidase Chloride peroxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.11.1.10 1.11.1.10] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1qi9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qi9 OCA], [http://www.ebi.ac.uk/pdbsum/1qi9 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1qi9 RCSB]</span> | ||
}} | }} | ||
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[[Category: Vilter, H.]] | [[Category: Vilter, H.]] | ||
[[Category: Weyand, M.]] | [[Category: Weyand, M.]] | ||
| - | [[Category: IOD]] | ||
| - | [[Category: VO4]] | ||
[[Category: bromoperoxidase]] | [[Category: bromoperoxidase]] | ||
[[Category: haloperoxidase]] | [[Category: haloperoxidase]] | ||
[[Category: vanadium]] | [[Category: vanadium]] | ||
| - | ''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 23:13:59 2008'' |
Revision as of 20:14, 30 March 2008
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| , resolution 2.05Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , | ||||||
| Activity: | Chloride peroxidase, with EC number 1.11.1.10 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
X-RAY SIRAS STRUCTURE DETERMINATION OF A VANADIUM-DEPENDENT HALOPEROXIDASE FROM ASCOPHYLLUM NODOSUM AT 2.0 A RESOLUTION
Overview
The homo-dimeric structure of a vanadium-dependent haloperoxidase (V-BPO) from the brown alga Ascophyllum nodosum (EC 1.1.11.X) has been solved by single isomorphous replacement anomalous scattering (SIRAS) X-ray crystallography at 2.0 A resolution (PDB accession code 1QI9), using two heavy-atom datasets of a tungstate derivative measured at two different wavelengths. The protein sequence (SwissProt entry code P81701) of V-BPO was established by combining results from protein and DNA sequencing, and electron density interpretation. The enzyme has nearly an all-helical structure, with two four-helix bundles and only three small beta-sheets. The holoenzyme contains trigonal-bipyramidal coordinated vanadium atoms at its two active centres. Structural similarity to the only other structurally characterized vanadium-dependent chloroperoxidase (V-CPO) from Curvularia inaequalis exists in the vicinity of the active site and to a lesser extent in the central four-helix bundle. Despite the low sequence and structural similarity between V-BPO and V-CPO, the vanadium binding centres are highly conserved on the N-terminal side of an alpha-helix and include the proposed catalytic histidine residue (His418(V-BPO)/His404(V-CPO)). The V-BPO structure contains, in addition, a second histidine near the active site (His411(V-BPO)), which can alter the redox potential of the catalytically active VO2-O2 species by protonation/deprotonation reactions. Specific binding sites for the organic substrates, like indoles and monochlordimedone, or for halide ions are not visible in the V-BPO structure. A reaction mechanism for the enzymatic oxidation of halides is discussed, based on the present structural, spectroscopic and biochemical knowledge of vanadium-dependent haloperoxidases, explaining the observed enzymatic differences between both enzymes.
About this Structure
1QI9 is a Single protein structure of sequence from Ascophyllum nodosum. Full crystallographic information is available from OCA.
Reference
X-ray structure determination of a vanadium-dependent haloperoxidase from Ascophyllum nodosum at 2.0 A resolution., Weyand M, Hecht H, Kiess M, Liaud M, Vilter H, Schomburg D, J Mol Biol. 1999 Oct 29;293(3):595-611. PMID:10543953
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