1twr: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1twr.gif|left|200px]] | [[Image:1twr.gif|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_1twr", creates the "Structure Box" on the page. | |||
You may change the PDB parameter (which sets the PDB file loaded into the applet) | |||
or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |||
or leave the SCENE parameter empty for the default display. | |||
| | --> | ||
| | {{STRUCTURE_1twr| PDB=1twr | SCENE= }} | ||
}} | |||
'''Crystal structures of ferrous and ferrous-NO forms of verdoheme in a complex with human heme oxygenase-1: catalytic implications for heme cleavage''' | '''Crystal structures of ferrous and ferrous-NO forms of verdoheme in a complex with human heme oxygenase-1: catalytic implications for heme cleavage''' | ||
| Line 29: | Line 26: | ||
[[Category: Montellano, P R.Ortiz de.]] | [[Category: Montellano, P R.Ortiz de.]] | ||
[[Category: Poulos, T L.]] | [[Category: Poulos, T L.]] | ||
[[Category: | [[Category: Heme degredation]] | ||
[[Category: | [[Category: Heme oxygenase-1]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 10:27:58 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 10:27, 3 May 2008
Crystal structures of ferrous and ferrous-NO forms of verdoheme in a complex with human heme oxygenase-1: catalytic implications for heme cleavage
OverviewOverview
Heme oxygenase oxidatively degrades heme to biliverdin resulting in the release of iron and CO through a process in which the heme participates both as a cofactor and substrate. One of the least understood steps in the heme degradation pathway is the conversion of verdoheme to biliverdin. In order to obtain a better understanding of this step we report the crystal structures of ferrous-verdoheme and, as a mimic for the oxy-verdoheme complex, ferrous-NO verdoheme in a complex with human HO-1 at 2.20 and 2.10 A, respectively. In both structures the verdoheme occupies the same binding location as heme in heme-HO-1, but rather than being ruffled verdoheme in both sets of structures is flat. Both structures are similar to their heme counterparts except for the distal helix and heme pocket solvent structure. In the ferrous-verdoheme structure the distal helix moves closer to the verdoheme, thus tightening the active site. NO binds to verdoheme in a similar bent conformation to that found in heme-HO-1. The bend angle in the verodoheme-NO structure places the terminal NO oxygen 1 A closer to the alpha-meso oxygen of verdoheme compared to the alpha-meso carbon on the heme-NO structure. A network of water molecules, which provide the required protons to activate the iron-oxy complex of heme-HO-1, is absent in both ferrous-verdoheme and the verdoheme-NO structure.
About this StructureAbout this Structure
1TWR is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of ferrous and ferrous-NO forms of verdoheme in a complex with human heme oxygenase-1: catalytic implications for heme cleavage., Lad L, Ortiz de Montellano PR, Poulos TL, J Inorg Biochem. 2004 Nov;98(11):1686-95. PMID:15522396 Page seeded by OCA on Sat May 3 10:27:58 2008