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ID 48619
file
creator
Kihara, Shogo
Bando, Naohiko
Yoshitsu, Hironari
Sakaguchi, Miyuki
Kayama, Kure'e
Yanagisawa, Sachiko
Ogura, Takashi
abstract
Tyrosinase (EC 1.14.18.1), a copper-containing monooxygenase, catalyzes the conversion of phenol to the corresponding ortho-quinone. The Streptomyces tyrosinase is generated as a complex with a “caddie” protein that facilitates the transport of two copper ions into the active center. In our previous study, the Tyr98 residue in the caddie protein, which is accommodated in the pocket of active center of tyrosinase, has been found to be converted to a reactive quinone through the formations of the μ-η2:η2-peroxo-dicopper(II) and Cu(II)-dopasemiquinone intermediates. Until now—despite extensive studies for the tyrosinase reaction based on the crystallographic analysis, low-molecular-weight models, and computer simulations—the catalytic mechanism has been unable to be made clear at an atomic level. To make the catalytic mechanism of tyrosinase clear, in the present study, the cryo-trapped crystal structures were determined at very high resolutions (1.16–1.70 Å). The structures suggest the existence of an important step for the tyrosinase reaction that has not yet been found: that is, the hydroxylation reaction is triggered by the movement of CuA, which induces the syn-to-anti rearrangement of the copper ligands after the formation of μ-η2:η2-peroxo-dicopper(II) core. By the rearrangement, the hydroxyl group of the substrate is placed in an equatorial position, allowing the electrophilic attack to the aromatic ring by the Cu2O2 oxidant.
description
This study was partly supported by grants (nos. 25109530 and 15H009470 to YM, and 25109540 and 15H00960 to TO, Stimuli-Responsive Chemical Species) for Scientific Research on Innovative Areas and by a grant for Scientific Research (22550153 to MS) from MEXT of Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
journal title
PLoS Biology
volume
Volume 16
issue
Issue 12
start page
e3000077
date of issued
2018-12-31
publisher
Public Library of Science
issn
1544-9173
1545-7885
publisher doi
language
eng
nii type
Journal Article
HU type
Journal Articles
DCMI type
text
format
application/pdf
text version
publisher
rights
© 2018 Matoba et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
relation url
department
Graduate School of Biomedical & Health Sciences



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