Key Laboratory of Aquatic Product Processing, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China.
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
Food Res Int. 2023 Jan;163:112307. doi: 10.1016/j.foodres.2022.112307. Epub 2022 Dec 8.
Binuclear copper ions at the active site determine the catalysis of tyrosinase (TYR) whose activity can be inhibited by copper's chelation with other compounds. In this study, tilapia (Oreochromis niloticus) skin was used to generate TYR-inhibitory peptides after being treated by different enzymes and 4 h-Alcaline protease hydrolysate exhibited the highest TYR inhibition and copper chelation. Immobilized metal affinity chromatography was used for purifying copper chelating peptides, among which PFRMY (IC: 0.43 ± 0.08 mg/mL) and RGFTGM (IC: 1.61 ± 0.04 mg/mL) exhibited the highest TYR-inhibitory capacity and the lowest docking energy. Both two peptides inhibited TYR in a mixed manner and interacted with key residues binding to copper ions within TYR mainly by hydrogen bonds and hydrophobic forces, while PFRMY had a more compact and stable conjugation with TYR. Zebrafish assay revealed that PFRMY reduced not only melanin synthesis but in vivo TYR activity.
活性部位的双核铜离子决定了酪氨酸酶（TYR）的催化作用，其活性可被铜与其他化合物螯合所抑制。在这项研究中，罗非鱼（Oreochromis niloticus）皮肤经不同酶处理后产生 TYR 抑制肽，4 h 碱性蛋白酶水解物表现出最高的 TYR 抑制和铜螯合活性。固定化金属亲和层析用于纯化铜螯合肽，其中 PFRMY（IC：0.43±0.08 mg/mL）和 RGFTGM（IC：1.61±0.04 mg/mL）表现出最高的 TYR 抑制能力和最低的对接能。这两种肽均以混合方式抑制 TYR，通过氢键和疏水相互作用与 TYR 中结合铜离子的关键残基相互作用，而 PFRMY 与 TYR 的结合更紧凑和稳定。斑马鱼试验表明，PFRMY 不仅减少了黑色素的合成，还降低了体内 TYR 活性。
