Role of Amino Acid Residues for Dioxygen Activation in the Second Coordination Sphere of the Dicopper Site of pMMO

Mayuko Miyanishi, Tsukasa Abe, Yuta Hori, Yoshihito Shiota, Kazunari Yoshizawa

研究成果: Contribution to journalArticle

抜粋

Formation of an active oxygen species at the dicopper site of pMMO is studied by using density functional theory (DFT) calculations. The role of the amino acid residues of tyrosine (Tyr374) and glutamate (Glu35) located in the second coordination sphere of the dicopper site is discussed in detail. The phenolic proton of the tyrosine residue is transferred to the Cu2O2 core in a two-step manner via the glutamate residue, and an electron is directly transferred to the Cu2O2 core. These proton- and electron-transfer processes induce the O-O bond cleavage of the μ-ν22-peroxodicopper(II) species to form the (μ-oxo)(μ-hydroxo)CuIICuIII species, which is able to play a key role of methane hydroxylation at the dicopper site of pMMO (Inorg. Chem. 2013, 52, 7907). This proton-coupled electron-transfer mechanism is a little different from that in tyrosinase in that the proton of substrate tyrosine is directly transferred to the dicopper site (J. Am. Chem. Soc. 2006, 128, 9873) because there is no proton acceptor in the vicinity of the dicopper site of tyrosinase. The rate-determining step for the formation of the (μ-oxo)(μ-hydroxo)CuIICuIII species is determined to be the O-O bond cleavage. These results shed new light on the interpretation of the role of the tyrosine and glutamate residues located in the second coordination sphere of the dicopper site of pMMO.

元の言語英語
ページ(範囲)12280-12288
ページ数9
ジャーナルInorganic chemistry
58
発行部数18
DOI
出版物ステータス出版済み - 9 16 2019

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry
  • Inorganic Chemistry

フィンガープリント Role of Amino Acid Residues for Dioxygen Activation in the Second Coordination Sphere of the Dicopper Site of pMMO' の研究トピックを掘り下げます。これらはともに一意のフィンガープリントを構成します。

  • これを引用