2a1m
From Proteopedia
(New page: 200px<br /><applet load="2a1m" size="450" color="white" frame="true" align="right" spinBox="true" caption="2a1m, resolution 2.10Å" /> '''Crystal structure of...) |
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| - | [[Image:2a1m.gif|left|200px]]<br /><applet load="2a1m" size=" | + | [[Image:2a1m.gif|left|200px]]<br /><applet load="2a1m" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2a1m, resolution 2.10Å" /> | caption="2a1m, resolution 2.10Å" /> | ||
'''Crystal structure of ferrous dioxygen complex of wild-type cytochrome P450cam'''<br /> | '''Crystal structure of ferrous dioxygen complex of wild-type cytochrome P450cam'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Two key amino acids, Thr252 and Asp251, are known to be important for | + | Two key amino acids, Thr252 and Asp251, are known to be important for dioxygen activation by cytochrome P450cam. We have solved crystal structures of a critical intermediate, the ferrous dioxygen complex (Fe(II)-O2), of the wild-type P450cam and its mutants, D251N and T252A. The wild-type dioxygen complex structure is very much the same as reported previously (Schlichting, I., Berendzen, J., Chu, K., Stock, A. M., Maves, S. A., Benson, D. E., Sweet, R. M., Ringe, D., Petsko, G. A., and Sligar, S. G. (2000) Science 287, 1615-1622) with the exception of higher occupancy and a more ordered structure of the iron-linked dioxygen and two "catalytic" water molecules that form part of a proton relay system to the iron-linked dioxygen. Due to of the altered conformation of the I helix groove these two waters are missing in the D251N dioxygen complex which explains its lower catalytic activity and slower proton transfer to the dioxygen ligand. Similarly, the T252A mutation was expected to disrupt the active site solvent structure leading to hydrogen peroxide formation rather than substrate hydroxylation. Unexpectedly, however, the two "catalytic" waters are retained in the T252A mutant. Based on these findings, we propose that the Thr(252) accepts a hydrogen bond from the hydroperoxy (Fe(III)-OOH) intermediate that promotes the second protonation on the distal oxygen atom, leading to O-O bond cleavage and compound I formation. |
==About this Structure== | ==About this Structure== | ||
| - | 2A1M 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 K, HEM, OXY, CAM and TRS 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:// | + | 2A1M 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=K:'>K</scene>, <scene name='pdbligand=HEM:'>HEM</scene>, <scene name='pdbligand=OXY:'>OXY</scene>, <scene name='pdbligand=CAM:'>CAM</scene> and <scene name='pdbligand=TRS:'>TRS</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=2A1M OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Nagano, S.]] | [[Category: Nagano, S.]] | ||
| - | [[Category: Poulos, T | + | [[Category: Poulos, T L.]] |
[[Category: CAM]] | [[Category: CAM]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
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[[Category: oxy]] | [[Category: oxy]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:22:45 2008'' |
Revision as of 14:22, 21 February 2008
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Crystal structure of ferrous dioxygen complex of wild-type cytochrome P450cam
Overview
Two key amino acids, Thr252 and Asp251, are known to be important for dioxygen activation by cytochrome P450cam. We have solved crystal structures of a critical intermediate, the ferrous dioxygen complex (Fe(II)-O2), of the wild-type P450cam and its mutants, D251N and T252A. The wild-type dioxygen complex structure is very much the same as reported previously (Schlichting, I., Berendzen, J., Chu, K., Stock, A. M., Maves, S. A., Benson, D. E., Sweet, R. M., Ringe, D., Petsko, G. A., and Sligar, S. G. (2000) Science 287, 1615-1622) with the exception of higher occupancy and a more ordered structure of the iron-linked dioxygen and two "catalytic" water molecules that form part of a proton relay system to the iron-linked dioxygen. Due to of the altered conformation of the I helix groove these two waters are missing in the D251N dioxygen complex which explains its lower catalytic activity and slower proton transfer to the dioxygen ligand. Similarly, the T252A mutation was expected to disrupt the active site solvent structure leading to hydrogen peroxide formation rather than substrate hydroxylation. Unexpectedly, however, the two "catalytic" waters are retained in the T252A mutant. Based on these findings, we propose that the Thr(252) accepts a hydrogen bond from the hydroperoxy (Fe(III)-OOH) intermediate that promotes the second protonation on the distal oxygen atom, leading to O-O bond cleavage and compound I formation.
About this Structure
2A1M 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
Crystallographic study on the dioxygen complex of wild-type and mutant cytochrome P450cam. Implications for the dioxygen activation mechanism., Nagano S, Poulos TL, J Biol Chem. 2005 Sep 9;280(36):31659-63. Epub 2005 Jun 30. PMID:15994329
Page seeded by OCA on Thu Feb 21 16:22:45 2008
Categories: Camphor 5-monooxygenase | Pseudomonas putida | Single protein | Nagano, S. | Poulos, T L. | CAM | HEM | K | OXY | TRS | Cyp | Cytochrome p450 | Dioxygen complex | Oxy
