A new thioether-ligated iron porphyrin as a model of a protonated form of P450 active site
| Autor: | Yasuteru Urano, Kazuya Kikuchi, Tetsuo Nagano, Takashi Dokoh, Tsunehiko Higuchi, Noriyuki Suzuki |
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| Rok vydání: | 2001 |
| Předmět: |
Binding Sites
Porphyrins biology Molecular Structure Active site Sulfides Photochemistry Ligands Biochemistry Porphyrin Heterolysis Inorganic Chemistry chemistry.chemical_compound chemistry Thioether Catalytic cycle Cytochrome P-450 Enzyme System Polymer chemistry biology.protein Cyclooctane Heme Oxidation-Reduction Bond cleavage Ethers |
| Zdroj: | Journal of inorganic biochemistry. 82(1-4) |
| ISSN: | 0162-0134 |
| Popis: | Thioether-ligated iron porphyrin (complex 1 ) was synthesized as a model of the protonated form of P450 to explore the possible involvement of the protonated form in the catalytic cycle, and ether-ligated iron porphyrin (complex 2 ) was also synthesized for comparison. The thioether and ether ligands enhanced heterolytic O–O bond cleavage of peroxy acid–iron porphyrin complex even in highly hydrophobic media without the assistance of acid or base, using m CPPAA as an oxidant. Competitive oxidation of cyclooctane/cyclooctene catalyzed by iron porphyrins showed that complexes 1 and 2 are less effective than heme thiolate (P450 and a synthetic heme thiolate (SR complex)) in oxidizing alkane. The possibility that thiol-ligated heme, which is a protonated form of heme thiolate, is not involved in the active intermediate structure of P450 is indicated by this result. This is the first report concerning the oxidizing ability of a thioether-ligated iron porphyrin. |
| Databáze: | OpenAIRE |
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