Green, Michael T. and Dawson, John H. and Gray, Harry B. (2004) Oxoiron(IV) in Chloroperoxidase Compound II Is Basic: Implications for P450 Chemistry. Science, 304 (5677). pp. 1653-1656. ISSN 0036-8075. doi:10.1126/science.1096897. https://resolver.caltech.edu/CaltechAUTHORS:20141114-143753781
Full text is not posted in this repository. Consult Related URLs below.
Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20141114-143753781
Abstract
With the use of x-ray absorption spectroscopy, we have found that the Fe-O bond in chloroperoxidase compound II (CPO-II) is much longer than expected for an oxoiron(IV) (ferryl) unit; notably, the experimentally determined bond length of 1.82(1) Å accords closely with density functional calculations on a protonated ferryl (Fe^(IV)-OH, 1.81 Å). The basicity of the CPO-II ferryl [pK_a > 8.2 (where K_a is the acid dissociation constant)] is attributable to strong electron donation by the axial thiolate. We suggest that the CPO-II protonated ferryl is a good model for the rebound intermediate in the P450 oxygenation cycle; with elevated pK_a values after one-electron reduction, thiolate-ligated ferryl radicals are competent to oxygenate saturated hydrocarbons at potentials that can be tolerated by folded polypeptide hosts.
Item Type: | Article | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Related URLs: |
| ||||||||||
ORCID: |
| ||||||||||
Additional Information: | © 2004 American Association for the Advancement of Science. 18 February 2004; Accepted 21 April 2004. We thank M. Bollinger, I. Dmochowski, J. Labinger, M. Machczynski, M. McGuirl, A. Tezcan, and J. Winkler for helpful discussions; G. George, I. Pickering, M. Latimer, B. Butler, A. Soo Hoo, S. Debeer George, D. Durkin, and other SSRL staff members for assistance with XAS measurements; and L. Hager for a CPO sample used in the initial experiments. Supported by NIH (GM26730 to J.H.D. and DK19038 to H.B.G.), NSF, and the Arnold and Mabel Beckman Foundation. | ||||||||||
Funders: |
| ||||||||||
Issue or Number: | 5677 | ||||||||||
DOI: | 10.1126/science.1096897 | ||||||||||
Record Number: | CaltechAUTHORS:20141114-143753781 | ||||||||||
Persistent URL: | https://resolver.caltech.edu/CaltechAUTHORS:20141114-143753781 | ||||||||||
Official Citation: | Green, M. T., Dawson, J. H., & Gray, H. B. (2004). Oxoiron(IV) in Chloroperoxidase Compound II Is Basic: Implications for P450 Chemistry. Science, 304(5677), 1653-1656. doi: 10.1126/science.1096897 | ||||||||||
Usage Policy: | No commercial reproduction, distribution, display or performance rights in this work are provided. | ||||||||||
ID Code: | 51798 | ||||||||||
Collection: | CaltechAUTHORS | ||||||||||
Deposited By: | INVALID USER | ||||||||||
Deposited On: | 15 Nov 2014 00:55 | ||||||||||
Last Modified: | 10 Nov 2021 19:15 |
Repository Staff Only: item control page