The objective of this study was to elucidate the influence of oxidative modifications of myofibrillar proteins (MPs) on their surface properties. Oxidative modifications (deamination, formation of disulfide bonds and Schiff bases), particle size, net surface charge, and binding ability of volatiles (2-enthylfuran, 1-octen-3-ol, hexanal, and octanal) of oxidized MPs was measured. Molecular docking of volatiles with actomyosin was performed using Qvina-W program and the specific oxidative modifications (monoxidation and deamination) of MPs were determined using LC-MS/MS. Results showed that oxidation of Cys (forming sulfinic, sulfonic, sulfenic acid, and disulfide bonds), monoxidation of Ala, Lys, Glu, and Asn, and deamination of Lys changed the surface properties of oxidized MPs including enhanced surface hydrophobicity and decreased affinity to volatile compounds and water. Overall, this study gives evidence of how protein oxidation affects the properties of MPs and therefore deteriorates fish meat quality.

本研究的目的是阐明肌原纤维蛋白 (MP) 的氧化修饰对其表面特性的影响。测量了氧化 MP 的氧化修饰（脱氨作用、二硫键和席夫碱的形成）、粒径、净表面电荷和挥发物（2-乙基呋喃、1-octen-3-ol、己醛和辛醛）的结合能力。使用 Qvina-W 程序进行挥发物与肌动球蛋白的分子对接，并使用 LC-MS/MS 确定 MP 的特定氧化修饰（一氧化和脱氨）。结果表明，Cys 的氧化（形成亚磺酸、磺酸、次磺酸和二硫键），Ala、Lys、Glu 和 Asn 的单氧化，Lys 的脱氨基作用改变了氧化 MP 的表面特性，包括增强的表面疏水性和降低对挥发性化合物和水的亲和力。总的来说，这项研究提供了蛋白质氧化如何影响 MP 的特性并因此降低鱼肉质量的证据。