From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
Line 1: |
Line 1: |
- | [[Image:1rov.gif|left|200px]] | + | {{Seed}} |
| + | [[Image:1rov.png|left|200px]] |
| | | |
| <!-- | | <!-- |
Line 9: |
Line 10: |
| {{STRUCTURE_1rov| PDB=1rov | SCENE= }} | | {{STRUCTURE_1rov| PDB=1rov | SCENE= }} |
| | | |
- | '''Lipoxygenase-3 Treated with Cumene Hydroperoxide'''
| + | ===Lipoxygenase-3 Treated with Cumene Hydroperoxide=== |
| | | |
| | | |
- | ==Overview==
| + | <!-- |
- | Lipoxygenase catalysis depends in a critical fashion on the redox properties of a unique mononuclear non-heme iron cofactor. The isolated enzyme contains predominantly, if not exclusively, iron(II), but the catalytically active form of the enzyme has iron(III). The activating oxidation of the iron takes place in a reaction with the hydroperoxide product of the catalyzed reaction. In a second peroxide-dependent process, lipoxygenases are also inactivated. To examine the redox activation/inactivation dichotomy in lipoxygenase chemistry, the interaction between lipoxygenase-1 (and -3) and cumene hydroperoxide was investigated. Cumene hydroperoxide was a reversible inhibitor of the reaction catalyzed by lipoxygenase-1 under standard assay conditions at high substrate concentrations. Reconciliation of the data with the currently held kinetic mechanism requires simultaneous binding of substrate and peroxide. The enzyme also was both oxidized and largely inactivated in a reaction with the peroxide in the absence of substrate. The consequences of this reaction for the enzyme included the hydroxylation at C beta of two amino acid side chains in the vicinity of the cofactor, Trp and Leu. The modifications were identified by mass spectrometry and X-ray crystallography. The peroxide-induced oxidation of iron was also accompanied by a subtle rearrangement in the coordination sphere of the non-heme iron atom. Since the enzyme retains catalytic activity, albeit diminished, after treatment with cumene hydroperoxide, the structure of the iron site may reflect the catalytically relevant form of the cofactor.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_14971933}}, adds the Publication Abstract to the page |
| + | (as it appears on PubMed at http://www.pubmed.gov), where 14971933 is the PubMed ID number. |
| + | --> |
| + | {{ABSTRACT_PUBMED_14971933}} |
| | | |
| ==About this Structure== | | ==About this Structure== |
Line 30: |
Line 34: |
| [[Category: Vahedi-Faridi, A.]] | | [[Category: Vahedi-Faridi, A.]] |
| [[Category: Beta hydroxylation]] | | [[Category: Beta hydroxylation]] |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 07:44:18 2008'' | + | |
| + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 05:08:15 2008'' |
Revision as of 02:08, 29 July 2008
Template:STRUCTURE 1rov
Lipoxygenase-3 Treated with Cumene Hydroperoxide
Template:ABSTRACT PUBMED 14971933
About this Structure
1ROV is a Single protein structure of sequence from Glycine max. Full crystallographic information is available from OCA.
Reference
Interaction between non-heme iron of lipoxygenases and cumene hydroperoxide: basis for enzyme activation, inactivation, and inhibition., Vahedi-Faridi A, Brault PA, Shah P, Kim YW, Dunham WR, Funk MO Jr, J Am Chem Soc. 2004 Feb 25;126(7):2006-15. PMID:14971933
Page seeded by OCA on Tue Jul 29 05:08:15 2008