Copper–Oxygen Dynamics in the Tyrosinase Mechanism
| Autor: | Shinobu Itoh, Sachiko Yanagisawa, Nobutaka Fujieda, Kyohei Umakoshi, Yuta Ochi, Yosuke Nishikawa, Genji Kurisu, Minoru Kubo |
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| Rok vydání: | 2020 |
| Předmět: |
Aspergillus oryzae
Tyrosinase chemistry.chemical_element Crystal structure Crystallography X-Ray 010402 general chemistry Photochemistry 01 natural sciences Oxygen Peroxide Catalysis Fungal Proteins chemistry.chemical_compound Bacterial Proteins Catalytic Domain Monophenol Monooxygenase 010405 organic chemistry Ligand Substrate (chemistry) General Medicine General Chemistry Copper Streptomyces 0104 chemical sciences Models Chemical chemistry Biocatalysis Tyrosine Protein Binding |
| Zdroj: | Angewandte Chemie International Edition. 59:13385-13390 |
| ISSN: | 1521-3773 1433-7851 |
| DOI: | 10.1002/anie.202004733 |
| Popis: | The dinuclear copper enzyme, tyrosinase, activates O2 to form a (μ-η2 :η2 -peroxido)dicopper(II) species, which hydroxylates phenols to catechols. However, the exact mechanism of phenolase reaction in the catalytic site of tyrosinase is still under debate. We herein report the near atomic resolution X-ray crystal structures of the active tyrosinases with substrate l-tyrosine. At their catalytic sites, CuA moved toward l-tyrosine (CuA1 → CuA2), whose phenol oxygen directly coordinates to CuA2, involving the movement of CuB (CuB1 → CuB2). The crystal structures and spectroscopic analyses of the dioxygen-bound tyrosinases demonstrated that the peroxide ligand rotated, spontaneously weakening its O-O bond. Thus, the copper migration induced by the substrate-binding is accompanied by rearrangement of the bound peroxide species so as to provide one of the peroxide oxygen atoms with access to the phenol substrate's ϵ carbon atom. |
| Databáze: | OpenAIRE |
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