1phc
From Proteopedia
(New page: 200px<br /><applet load="1phc" size="450" color="white" frame="true" align="right" spinBox="true" caption="1phc, resolution 1.6Å" /> '''CRYSTAL STRUCTURE OF ...) |
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| - | [[Image:1phc.gif|left|200px]]<br /><applet load="1phc" size=" | + | [[Image:1phc.gif|left|200px]]<br /><applet load="1phc" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1phc, resolution 1.6Å" /> | caption="1phc, resolution 1.6Å" /> | ||
'''CRYSTAL STRUCTURE OF SUBSTRATE-FREE PSEUDOMONAS PUTIDA CYTOCHROME P450'''<br /> | '''CRYSTAL STRUCTURE OF SUBSTRATE-FREE PSEUDOMONAS PUTIDA CYTOCHROME P450'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structure of Pseudomonas putida cytochrome P-450cam in the | + | The crystal structure of Pseudomonas putida cytochrome P-450cam in the substrate-free form has been refined at 2.20-A resolution and compared to the substrate-bound form of the enzyme. In the absence of the substrate camphor, the P-450cam heme iron atom is hexacoordinate with the sulfur atom of Cys-357 providing one axial heme ligand and a water molecule or hydroxide ion providing the other axial ligand. A network of hydrogen-bonded solvent molecules occupies the substrate pocket in addition to the iron-linked aqua ligand. When a camphor molecule binds, the active site waters including the aqua ligand are displaced, resulting in a pentacoordinate high-spin heme iron atom. Analysis of the Fno camphor - F camphor difference Fourier and a quantitative comparison of the two refined structures reveal that no detectable conformational change results from camphor binding other than a small repositioning of a phenylalanine side chain that contacts the camphor molecule. However, large decreases in the mean temperature factors of three separate segments of the protein centered on Tyr-96, Thr-185, and Asp-251 result from camphor binding. This indicates that camphor binding decreases the flexibility in these three regions of the P-450cam molecule without altering the mean position of the atoms involved. |
==About this Structure== | ==About this Structure== | ||
| - | 1PHC 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 as [http://en.wikipedia.org/wiki/ligand ligand]. 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:// | + | 1PHC 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> as [http://en.wikipedia.org/wiki/ligand ligand]. 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=1PHC 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: HEM]] | [[Category: HEM]] | ||
[[Category: oxidoreductase(oxygenase)]] | [[Category: oxidoreductase(oxygenase)]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:28:46 2008'' |
Revision as of 12:28, 21 February 2008
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CRYSTAL STRUCTURE OF SUBSTRATE-FREE PSEUDOMONAS PUTIDA CYTOCHROME P450
Overview
The crystal structure of Pseudomonas putida cytochrome P-450cam in the substrate-free form has been refined at 2.20-A resolution and compared to the substrate-bound form of the enzyme. In the absence of the substrate camphor, the P-450cam heme iron atom is hexacoordinate with the sulfur atom of Cys-357 providing one axial heme ligand and a water molecule or hydroxide ion providing the other axial ligand. A network of hydrogen-bonded solvent molecules occupies the substrate pocket in addition to the iron-linked aqua ligand. When a camphor molecule binds, the active site waters including the aqua ligand are displaced, resulting in a pentacoordinate high-spin heme iron atom. Analysis of the Fno camphor - F camphor difference Fourier and a quantitative comparison of the two refined structures reveal that no detectable conformational change results from camphor binding other than a small repositioning of a phenylalanine side chain that contacts the camphor molecule. However, large decreases in the mean temperature factors of three separate segments of the protein centered on Tyr-96, Thr-185, and Asp-251 result from camphor binding. This indicates that camphor binding decreases the flexibility in these three regions of the P-450cam molecule without altering the mean position of the atoms involved.
About this Structure
1PHC is a Single protein structure of sequence from Pseudomonas putida with as ligand. Active as Camphor 5-monooxygenase, with EC number 1.14.15.1 Full crystallographic information is available from OCA.
Reference
Crystal structure of substrate-free Pseudomonas putida cytochrome P-450., Poulos TL, Finzel BC, Howard AJ, Biochemistry. 1986 Sep 9;25(18):5314-22. PMID:3768350
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