7cpp
From Proteopedia
(New page: 200px<br /><applet load="7cpp" size="450" color="white" frame="true" align="right" spinBox="true" caption="7cpp, resolution 2.0Å" /> '''THE STRUCTURAL BASIS ...) |
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| - | [[Image:7cpp.gif|left|200px]]<br /><applet load="7cpp" size=" | + | [[Image:7cpp.gif|left|200px]]<br /><applet load="7cpp" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="7cpp, resolution 2.0Å" /> | caption="7cpp, resolution 2.0Å" /> | ||
'''THE STRUCTURAL BASIS FOR SUBSTRATE-INDUCED CHANGES IN REDOX POTENTIAL AND SPIN EQUILIBRIUM IN CYTOCHROME P450(CAM)'''<br /> | '''THE STRUCTURAL BASIS FOR SUBSTRATE-INDUCED CHANGES IN REDOX POTENTIAL AND SPIN EQUILIBRIUM IN CYTOCHROME P450(CAM)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structures of cytochrome P-450CAM complexed with the | + | The crystal structures of cytochrome P-450CAM complexed with the alternative substrates norcamphor and adamantanone have been refined at 2.0-A resolution and compared with the native, camphor-bound form of the enzyme. Norcamphor lacks the 8-, 9-, and 10-methyl groups of camphor. Thus, specific interactions between these groups and phenylalanine 87 and valines 247 and 295 are missing in the norcamphor complex. As a result, norcamphor binds about 0.9 A further from the oxygen-binding site than does camphor, which allows sufficient room for a water molecule or hydroxide ion to remain coordinated with the heme iron atom. The larger adamantanone occupies a position closer to that of camphor and, as in the camphor-bound enzyme, the heme iron remains pentacoordinate with no solvent molecule coordinated as a sixth ligand. A comparison of crystallographic temperature factors indicates that norcamphor is more "loosely" bound than are either camphor or adamantanone, as might be expected from the relative sizes of the different substrates. The looser fit of norcamphor in the active-site pocket results in a less specific pattern of hydroxylation. The presence of an aqua ligand is the likely structural basis for the norcamphor-P-450CAM complex having both a lower redox potential and higher percentage of low-spin heme than do either the camphor-P-450CAM or adamantanone-P-450CAM complexes. |
==About this Structure== | ==About this Structure== | ||
| - | 7CPP is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_putida Pseudomonas putida] with HEM and NCM as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Camphor_5-monooxygenase Camphor 5-monooxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.15.1 1.14.15.1] Full crystallographic information is available from [http:// | + | 7CPP is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_putida Pseudomonas putida] with <scene name='pdbligand=HEM:'>HEM</scene> and <scene name='pdbligand=NCM:'>NCM</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Camphor_5-monooxygenase Camphor 5-monooxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.15.1 1.14.15.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7CPP OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Pseudomonas putida]] | [[Category: Pseudomonas putida]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Poulos, T | + | [[Category: Poulos, T L.]] |
[[Category: Raag, R.]] | [[Category: Raag, R.]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
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[[Category: oxidoreductase(oxygenase)]] | [[Category: oxidoreductase(oxygenase)]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:17:01 2008'' |
Revision as of 17:17, 21 February 2008
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THE STRUCTURAL BASIS FOR SUBSTRATE-INDUCED CHANGES IN REDOX POTENTIAL AND SPIN EQUILIBRIUM IN CYTOCHROME P450(CAM)
Overview
The crystal structures of cytochrome P-450CAM complexed with the alternative substrates norcamphor and adamantanone have been refined at 2.0-A resolution and compared with the native, camphor-bound form of the enzyme. Norcamphor lacks the 8-, 9-, and 10-methyl groups of camphor. Thus, specific interactions between these groups and phenylalanine 87 and valines 247 and 295 are missing in the norcamphor complex. As a result, norcamphor binds about 0.9 A further from the oxygen-binding site than does camphor, which allows sufficient room for a water molecule or hydroxide ion to remain coordinated with the heme iron atom. The larger adamantanone occupies a position closer to that of camphor and, as in the camphor-bound enzyme, the heme iron remains pentacoordinate with no solvent molecule coordinated as a sixth ligand. A comparison of crystallographic temperature factors indicates that norcamphor is more "loosely" bound than are either camphor or adamantanone, as might be expected from the relative sizes of the different substrates. The looser fit of norcamphor in the active-site pocket results in a less specific pattern of hydroxylation. The presence of an aqua ligand is the likely structural basis for the norcamphor-P-450CAM complex having both a lower redox potential and higher percentage of low-spin heme than do either the camphor-P-450CAM or adamantanone-P-450CAM complexes.
About this Structure
7CPP is a Single protein structure of sequence from Pseudomonas putida with and as ligands. Active as Camphor 5-monooxygenase, with EC number 1.14.15.1 Full crystallographic information is available from OCA.
Reference
The structural basis for substrate-induced changes in redox potential and spin equilibrium in cytochrome P-450CAM., Raag R, Poulos TL, Biochemistry. 1989 Jan 24;28(2):917-22. PMID:2713354
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