From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:1eup.gif|left|200px]] | + | [[Image:1eup.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 12: |
Line 12: |
| | | | |
| | | | |
| - | ==Overview==
| + | {{ABSTRACT_10716705}} |
| - | Several mammalian cytochrome P450 (P450) isoforms demonstrate homotropic cooperativity with a number of substrates, including steroids and polycyclic aromatic hydrocarbons. To identify structural factors contributing to steroid and polycyclic aromatic hydrocarbon binding to P450 enzymes and to determine the location of the allosteric site, we investigated interactions of the macrolide hydroxylase P450eryF from Saccharopolyspora erythraea with androstenedione and 9-aminophenanthrene. Spectroscopic binding assays indicate that P450eryF binds androstenedione with an affinity of 365 microM and a Hill coefficient of 1.31 +/- 0.6 and coordinates with 9-aminophenanthrene with an affinity of 91 microM and a Hill coefficient of 1.38 +/- 0.2. Crystals of complexes of androstenedione and 9-aminophenanthrene with P450eryF were grown and diffracted to 2.1 A and 2.35 A, respectively. Electron density maps indicate that for both complexes two ligand molecules are simultaneously present in the active site. The P450eryF/androstenedione model was refined to an r = 18.9%, and the two androstenedione molecules have similar conformations. The proximal androstenedione is positioned such that the alpha-face of carbon-6 is closest to the heme iron, and the second steroid molecule is positioned 5.5 A distal in the active site. The P450eryF/9-aminophenanthrene model was refined to an r = 19.7% with the proximal 9-aminophenanthrene coordinated with the heme iron through the 9-amino group and the second ligand positioned approximately 6 A distal in the active site. These results establish that homotropic cooperativity in ligand binding can result from binding of two substrate molecules within the active site pocket without major conformational changes in the protein.
| + | |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| | 1EUP is a [[Single protein]] structure. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1eh0 1eh0]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EUP OCA]. | | 1EUP is a [[Single protein]] structure. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1eh0 1eh0]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EUP OCA]. |
| - | | |
| - | ==Reference== | |
| - | Crystal structures of ligand complexes of P450eryF exhibiting homotropic cooperativity., Cupp-Vickery J, Anderson R, Hatziris Z, Proc Natl Acad Sci U S A. 2000 Mar 28;97(7):3050-5. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10716705 10716705] | |
| | [[Category: Single protein]] | | [[Category: Single protein]] |
| | [[Category: Anderson, R.]] | | [[Category: Anderson, R.]] |
| Line 28: |
Line 24: |
| | [[Category: Cytochrome p450eryf]] | | [[Category: Cytochrome p450eryf]] |
| | [[Category: Steroid]] | | [[Category: Steroid]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 15:32:20 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jun 25 19:16:30 2008'' |
Revision as of 16:16, 25 June 2008
Template:STRUCTURE 1eup
X-RAY CRYSTAL STRUCTURE OF CYTOCHROME P450ERYF WITH ANDROSTENDIONE BOUND
Template:ABSTRACT 10716705
About this Structure
1EUP is a Single protein structure. This structure supersedes the now removed PDB entry 1eh0. Full crystallographic information is available from OCA.
Page seeded by OCA on Wed Jun 25 19:16:30 2008
