1p3t
From Proteopedia
(New page: 200px<br /><applet load="1p3t" size="450" color="white" frame="true" align="right" spinBox="true" caption="1p3t, resolution 2.10Å" /> '''Crystal Structures o...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1p3t.jpg|left|200px]]<br /><applet load="1p3t" size=" | + | [[Image:1p3t.jpg|left|200px]]<br /><applet load="1p3t" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1p3t, resolution 2.10Å" /> | caption="1p3t, resolution 2.10Å" /> | ||
'''Crystal Structures of the NO-and CO-Bound Heme Oxygenase From Neisseria Meningitidis: Implications for Oxygen Activation'''<br /> | '''Crystal Structures of the NO-and CO-Bound Heme Oxygenase From Neisseria Meningitidis: Implications for Oxygen Activation'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Heme oxygenases catalyze the oxidation of heme to biliverdin, carbon | + | Heme oxygenases catalyze the oxidation of heme to biliverdin, carbon monoxide, and free iron while playing a critical role in mammalian heme homeostasis. Pathogenic bacteria such as Neisseriae meningitidis also produce heme oxygenase as part of a mechanism to mine host iron. The key step in heme oxidation is the regioselective oxidation of the heme alpha-meso-carbon by an activated Fe(III)-OOH complex. The structures of various diatomic ligands bound to the heme iron can mimic the dioxygen complex and provide important insights on the mechanism of O2 activation. Here we report the crystal structures of N. meningitidis heme oxygenase (nm-HO) in the Fe(II), Fe(II)-CO, and Fe(II)-NO states and compare these to the NO complex of human heme oxygenase-1 (Lad, L., Wang, J., Li, H., Friedman, J., Bhaskar, B., Ortiz de Montellano, P. R., and Poulos, T. L. (2003) J. Mol. Biol. 330, 527-538). Coordination of NO or CO results in a reorientation of Arg-77 that enables Arg-77 to participate in an active site H-bonded network involving a series of water molecules. One of these water molecules directly H-bonds to the Fe(II)-linked ligand and very likely serves as the proton source required for oxygen activation. Although the active site residues differ between nm-HO and human HO-1, the close similarity in the H-bonded water network suggests a common mechanism shared by all heme oxygenases. |
==About this Structure== | ==About this Structure== | ||
| - | 1P3T is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Neisseria_meningitidis Neisseria meningitidis] with HEM as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Heme_oxygenase Heme oxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.99.3 1.14.99.3] Full crystallographic information is available from [http:// | + | 1P3T is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Neisseria_meningitidis Neisseria meningitidis] with <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Heme_oxygenase Heme oxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.99.3 1.14.99.3] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1P3T OCA]. |
==Reference== | ==Reference== | ||
| Line 18: | Line 18: | ||
[[Category: Lad, L.]] | [[Category: Lad, L.]] | ||
[[Category: Li, H.]] | [[Category: Li, H.]] | ||
| - | [[Category: Poulos, T | + | [[Category: Poulos, T L.]] |
[[Category: Wilks, A.]] | [[Category: Wilks, A.]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
| Line 24: | Line 24: | ||
[[Category: heme oxygenase]] | [[Category: heme oxygenase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:24:52 2008'' |
Revision as of 12:24, 21 February 2008
|
Crystal Structures of the NO-and CO-Bound Heme Oxygenase From Neisseria Meningitidis: Implications for Oxygen Activation
Overview
Heme oxygenases catalyze the oxidation of heme to biliverdin, carbon monoxide, and free iron while playing a critical role in mammalian heme homeostasis. Pathogenic bacteria such as Neisseriae meningitidis also produce heme oxygenase as part of a mechanism to mine host iron. The key step in heme oxidation is the regioselective oxidation of the heme alpha-meso-carbon by an activated Fe(III)-OOH complex. The structures of various diatomic ligands bound to the heme iron can mimic the dioxygen complex and provide important insights on the mechanism of O2 activation. Here we report the crystal structures of N. meningitidis heme oxygenase (nm-HO) in the Fe(II), Fe(II)-CO, and Fe(II)-NO states and compare these to the NO complex of human heme oxygenase-1 (Lad, L., Wang, J., Li, H., Friedman, J., Bhaskar, B., Ortiz de Montellano, P. R., and Poulos, T. L. (2003) J. Mol. Biol. 330, 527-538). Coordination of NO or CO results in a reorientation of Arg-77 that enables Arg-77 to participate in an active site H-bonded network involving a series of water molecules. One of these water molecules directly H-bonds to the Fe(II)-linked ligand and very likely serves as the proton source required for oxygen activation. Although the active site residues differ between nm-HO and human HO-1, the close similarity in the H-bonded water network suggests a common mechanism shared by all heme oxygenases.
About this Structure
1P3T is a Single protein structure of sequence from Neisseria meningitidis with as ligand. Active as Heme oxygenase, with EC number 1.14.99.3 Full crystallographic information is available from OCA.
Reference
Crystal structures of the NO- and CO-bound heme oxygenase from Neisseriae meningitidis. Implications for O2 activation., Friedman J, Lad L, Deshmukh R, Li H, Wilks A, Poulos TL, J Biol Chem. 2003 Sep 5;278(36):34654-9. Epub 2003 Jun 22. PMID:12819228
Page seeded by OCA on Thu Feb 21 14:24:52 2008
