文献类型：期刊文献

英文题名：Conformational changes of tyrosinase caused by pentagalloylglucose binding: Implications for inhibitory effect and underlying mechanism

作者：Liu, Lulu[1] Li, Jingda[1] Zhang, Liangliang[2] Wei, Shudong[1,4] Qin, Zeya[1] Liang, Dandan[1] Ding, Baomiao[1] Chen, Hui[1] Song, Wei[1,3]

第一作者：Liu, Lulu

机构：[1] College of Life Science and Engineering Research Center of Ecology and Agricultural Use of Wetland, Ministry of Education, Yangtze University, Jingzhou, China; [2] Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry, Nanjing, China; [3] College of Life Science and Engineering, Henan University of Urban Construction, Pingdingshan, China; [4] Institute of Food Science and Technology, Yangtze University, Jingzhou, China

年份：2022

卷号：157

外文期刊名：Food Research International

收录：EI(收录号：20222112141393);Scopus(收录号：2-s2.0-85130412579)

基金：This work was supported by grants from the National Natural Science Foundation of China (31972013), the Science and Technology Research Project from Hubei Provincial Department of Education (D20191301), and the Engineering Research Center of Ecology and Agricultural Use of Wetland, Ministry of Education, Yangtze University (KF202010, KF202013).

语种：英文

外文关键词：Chelation - Circular dichroism spectroscopy - Conformations - Copper - Enzyme kinetics - Fluorescence - Fourier transform infrared spectroscopy - Hydrogen bonds - Metal ions

摘要：Tyrosinase is a critical enzyme related to various pigmentation disorders and browning of fruits and vegetables. In this study, a novel inhibitor pentagalloylglucose (PGG) against tyrosinase was prepared from tannic acid with the chemical structure elucidated using HPLC, ESI-MS, 1H- and 13C NMR. Its inhibitory effect and the underlying mechanism on tyrosinase were explored by enzyme kinetics, UV-scanning, copper-ion chelation, fluorescence, circular dichroism, fourier transform infrared spectroscopy and molecular docking simulation. Results revealed that the yield of PGG reached 18.0% and the purity was up to 99.09%. PGG was a high-potential inhibitor of tyrosinase with IC50 values of (15.54 ± 0.56) × 10-6 and (50.89 ± 3.34) × 10-6 mol/L for monophenolase and diphenolase, respectively. PGG could disturb the formation of dopachrome and had strong capacity to chelate copper ions. The fluorescence of tyrosinase was efficiently quenched by PGG through a static mechanism. The binding of PGG to tyrosinase was a spontaneous exothermic process that induced unfolding of the tyrosinase structure to expose more buried hydrophobic residues. Docking results implied that PGG interacted with tyrosinase by forming hydrogen bonds with amino acid residues Glu-173, Glu-208, Lys-158, Lys-180, Gln-44 and Gln-159. This study would enhance our understanding of the inhibitory mechanism of PGG on tyrosinase at the molecular level and provide scientific guidance for the application of PGG in food and pharmaceutical industries. ? 2022 Elsevier Ltd