1iw1: Difference between revisions

← Older edit Newer edit →

Revision as of 21:25, 30 March 2008

File:1iw1.jpg

, resolution 1.50Å

Ligands:

, ,

Activity:

Heme oxygenase, with EC number 1.14.99.3

Related:

1IW0

Resources:

FirstGlance, OCA, PDBsum, RCSB

Coordinates:

save as pdb, mmCIF, xml

Crystal structure of a heme oxygenase (HmuO) from Corynebacterium diphtheriae complexed with heme in the ferrous state

OverviewOverview

Crystal structures of the ferric and ferrous heme complexes of HmuO, a 24-kDa heme oxygenase of Corynebacterium diphtheriae, have been refined to 1.4 and 1.5 A resolution, respectively. The HmuO structures show that the heme group is closely sandwiched between the proximal and distal helices. The imidazole group of His-20 is the proximal heme ligand, which closely eclipses the beta- and delta-meso axis of the porphyrin ring. A long range hydrogen bonding network is present, connecting the iron-bound water ligand to the solvent water molecule. This enables proton transfer from the solvent to the catalytic site, where the oxygen activation occurs. In comparison to the ferric complex, the proximal and distal helices move closer to the heme plane in the ferrous complex. Together with the kinked distal helix, this movement leaves only the alpha-meso carbon atom accessible to the iron-bound dioxygen. The heme pocket architecture is responsible for stabilization of the ferric hydroperoxo-active intermediate by preventing premature heterolytic O-O bond cleavage. This allows the enzyme to oxygenate selectively at the alpha-meso carbon in HmuO catalysis.

About this StructureAbout this Structure

1IW1 is a Single protein structure of sequence from Corynebacterium diphtheriae. Full crystallographic information is available from OCA.

ReferenceReference

The crystal structures of the ferric and ferrous forms of the heme complex of HmuO, a heme oxygenase of Corynebacterium diphtheriae., Hirotsu S, Chu GC, Unno M, Lee DS, Yoshida T, Park SY, Shiro Y, Ikeda-Saito M, J Biol Chem. 2004 Mar 19;279(12):11937-47. Epub 2003 Nov 26. PMID:14645223

Page seeded by OCA on Sun Mar 30 21:25:27 2008

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

OCA

@@ Line 4: / Line 4: @@
 |PDB= 1iw1 |SIZE=350|CAPTION= <scene name='initialview01'>1iw1</scene>, resolution 1.50&Aring;
 |SITE=
-|LIGAND= <scene name='pdbligand=SUC:SUCROSE'>SUC</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene> and <scene name='pdbligand=HEM:PROTOPORPHYRIN IX CONTAINING FE'>HEM</scene>
+|LIGAND= <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=SUC:SUCROSE'>SUC</scene>
-|ACTIVITY= [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]
+|ACTIVITY= <span class='plainlinks'>[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] </span>
 |GENE=
+|DOMAIN=
+|RELATEDENTRY=[[1iw0|1IW0]]
+|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1iw1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1iw1 OCA], [http://www.ebi.ac.uk/pdbsum/1iw1 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1iw1 RCSB]</span>
 }}
@@ Line 31: / Line 34: @@
 [[Category: Shiro, Y.]]
 [[Category: Unno, M.]]
-[[Category: HEM]]
-[[Category: SO4]]
-[[Category: SUC]]
 [[Category: alpha helix]]
 [[Category: bacterial iron acquisition]]
@@ Line 40: / Line 40: @@
 [[Category: structural genomic]]
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 11:55:38 2008''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:25:27 2008''