2rfc
From Proteopedia
(New page: 200px<br /><applet load="2rfc" size="350" color="white" frame="true" align="right" spinBox="true" caption="2rfc, resolution 3.10Å" /> '''Ligand bound (4-phen...) |
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==Overview== | ==Overview== | ||
| - | The crystal structure of a cytochrome P450 from the thermoacidophile | + | The crystal structure of a cytochrome P450 from the thermoacidophile Picrophilus torridus, CYP231A2 (PTO1399), has been solved. This structure reveals a wide open substrate access channel. To better understand ligand-induced structural transitions in CYP231A2, protein-ligand interactions were investigated using 4-phenylimidazole. Comparison of the ligand-free and -bound CYP231A2 structures shows conformational changes where the F and G helices swing as a single rigid body about a pivot point at the N-terminal end of the F helix, allowing the F helix region to dip toward the heme, resulting in closer contacts with the ligand. Thermal melting data illustrate that the melting temperature for CYP231A2 increases nearly 10 degrees C upon ligand binding, thus illustrating that the closed conformation is substantially more stable. Furthermore, spectroscopic data indicate that the active site is stable at pH 4.5, although, unusually, the thiolate ligand to the iron can be reversibly protonated. CYP231A2 does not exhibit structural features normally associated with thermophilic proteins such as an increase in salt bridge networks or extensive aromatic clustering. The increase in thermal stability instead is best correlated with the smaller size and shorter loops in CYP231A2 compared to other P450s. |
==About this Structure== | ==About this Structure== | ||
| - | 2RFC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Picrophilus_torridus Picrophilus torridus] with <scene name='pdbligand=HEM:'>HEM</scene> and <scene name='pdbligand=PIM:'>PIM</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Unspecific_monooxygenase Unspecific monooxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.14.1 1.14.14.1] Known structural/functional Sites: <scene name='pdbsite=AC1:Hem Binding Site For Residue A 410'>AC1</scene>, <scene name='pdbsite=AC2:Pim Binding Site For Residue A 411'>AC2</scene>, <scene name='pdbsite=AC3:Hem Binding Site For Residue B 410'>AC3</scene>, <scene name='pdbsite=AC4:Pim Binding Site For Residue B 411'>AC4</scene>, <scene name='pdbsite=AC5:Hem Binding Site For Residue C 410'>AC5</scene>, <scene name='pdbsite=AC6:Pim Binding Site For Residue C 411'>AC6</scene>, <scene name='pdbsite=AC7:Hem Binding Site For Residue D 410'>AC7</scene> and <scene name='pdbsite=AC8:Pim Binding Site For Residue D 411'>AC8</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2RFC OCA]. | + | 2RFC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Picrophilus_torridus Picrophilus torridus] with <scene name='pdbligand=HEM:'>HEM</scene> and <scene name='pdbligand=PIM:'>PIM</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Unspecific_monooxygenase Unspecific monooxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.14.1 1.14.14.1] Known structural/functional Sites: <scene name='pdbsite=AC1:Hem+Binding+Site+For+Residue+A+410'>AC1</scene>, <scene name='pdbsite=AC2:Pim+Binding+Site+For+Residue+A+411'>AC2</scene>, <scene name='pdbsite=AC3:Hem+Binding+Site+For+Residue+B+410'>AC3</scene>, <scene name='pdbsite=AC4:Pim+Binding+Site+For+Residue+B+411'>AC4</scene>, <scene name='pdbsite=AC5:Hem+Binding+Site+For+Residue+C+410'>AC5</scene>, <scene name='pdbsite=AC6:Pim+Binding+Site+For+Residue+C+411'>AC6</scene>, <scene name='pdbsite=AC7:Hem+Binding+Site+For+Residue+D+410'>AC7</scene> and <scene name='pdbsite=AC8:Pim+Binding+Site+For+Residue+D+411'>AC8</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2RFC OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal Structure and Properties of CYP231A2 from the Thermoacidophilic Archaeon Picrophilus torridus(,)., Ho WW, Li H, Nishida CR, Montellano PR, Poulos TL, Biochemistry. 2008 Jan 16 | + | Crystal Structure and Properties of CYP231A2 from the Thermoacidophilic Archaeon Picrophilus torridus(,)., Ho WW, Li H, Nishida CR, Montellano PR, Poulos TL, Biochemistry. 2008 Feb 19;47(7):2071-9. Epub 2008 Jan 16. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=18197710 18197710] |
[[Category: Picrophilus torridus]] | [[Category: Picrophilus torridus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Unspecific monooxygenase]] | [[Category: Unspecific monooxygenase]] | ||
| - | [[Category: Ho, W | + | [[Category: Ho, W W.]] |
[[Category: Li, H.]] | [[Category: Li, H.]] | ||
| - | [[Category: Montellano, P | + | [[Category: Montellano, P R.Ortiz de.]] |
| - | [[Category: Nishida, C | + | [[Category: Nishida, C R.]] |
| - | [[Category: Poulos, T | + | [[Category: Poulos, T L.]] |
[[Category: HEM]] | [[Category: HEM]] | ||
[[Category: PIM]] | [[Category: PIM]] | ||
| Line 28: | Line 28: | ||
[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:46:50 2008'' |
Revision as of 16:46, 21 February 2008
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Ligand bound (4-phenylimidazole) Crystal Structure of a Cytochrome P450 from the Thermoacidophilic Archaeon Picrophilus Torridus
Overview
The crystal structure of a cytochrome P450 from the thermoacidophile Picrophilus torridus, CYP231A2 (PTO1399), has been solved. This structure reveals a wide open substrate access channel. To better understand ligand-induced structural transitions in CYP231A2, protein-ligand interactions were investigated using 4-phenylimidazole. Comparison of the ligand-free and -bound CYP231A2 structures shows conformational changes where the F and G helices swing as a single rigid body about a pivot point at the N-terminal end of the F helix, allowing the F helix region to dip toward the heme, resulting in closer contacts with the ligand. Thermal melting data illustrate that the melting temperature for CYP231A2 increases nearly 10 degrees C upon ligand binding, thus illustrating that the closed conformation is substantially more stable. Furthermore, spectroscopic data indicate that the active site is stable at pH 4.5, although, unusually, the thiolate ligand to the iron can be reversibly protonated. CYP231A2 does not exhibit structural features normally associated with thermophilic proteins such as an increase in salt bridge networks or extensive aromatic clustering. The increase in thermal stability instead is best correlated with the smaller size and shorter loops in CYP231A2 compared to other P450s.
About this Structure
2RFC is a Single protein structure of sequence from Picrophilus torridus with and as ligands. Active as Unspecific monooxygenase, with EC number 1.14.14.1 Known structural/functional Sites: , , , , , , and . Full crystallographic information is available from OCA.
Reference
Crystal Structure and Properties of CYP231A2 from the Thermoacidophilic Archaeon Picrophilus torridus(,)., Ho WW, Li H, Nishida CR, Montellano PR, Poulos TL, Biochemistry. 2008 Feb 19;47(7):2071-9. Epub 2008 Jan 16. PMID:18197710
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