Axial bonds at the T1 Cu site of Thermusthermophilus SG0.5JP17-16 laccase influence enzymatic properties
Axial bonds at the T1 Cu site of Thermusthermophilus SG0.5JP17-16 laccase influence enzymatic properties
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嗜热菌 SG0.5JP17-16 漆酶 T1 Cu 位点的轴向键影响酶性质
DOI：
10.1002/2211-5463.12633
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发表时间：
2019
期刊：
影响因子：
2.6
通讯作者：
Yang Xiaorong
中科院分区：
文献类型：
--
作者：
Zhu Yanyun;Zhang Yi;Zhan Jiangbo;Lin Ying;Yang Xiaorong
Laccase is a multi‐copper oxidase which oxidizes substrate at the type 1 copper site, simultaneously coupling the reduction of dioxygen to water at the trinuclear copper center. In this study, we used site‐directed mutagenesis to study the effect of axial bonds between the metal and amino acid residue side chains in lacTT. Our kinetic and spectral data showed that the replacement of the axial residue with non‐coordinating residues resulted in higher efficiency (kcat/Km) and a lower Cu2+population at the type 1 copper site, while substitution with strongly coordinating residues resulted in lower efficiency and a higher Cu2+population, as compared with the wild‐type. The redox potentials of mutants with hydrophobic axial residues (Ala and Phe) were higher than that of the wild‐type. In conclusion, these insights into the catalytic mechanism of laccase may be of use in protein engineering to fine‐tune its enzymatic properties for industrial application.
