NutriFOODchem Unit, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University , Coupure links 653, B-9000 Ghent, Belgium.
J Agric Food Chem. 2013 Dec 26;61(51):12727-36. doi: 10.1021/jf404396c. Epub 2013 Dec 12.
Protein oxidation can have major implications on the quality and safety of foods, but the majority of methods to evaluate oxidative damage lack specificity. Therefore, this study aimed to identify specific markers for protein oxidation. A well-characterized protein, lysozyme, was modified by photo-oxidation and subsequently hydrolyzed prior to peptide analysis by LC-TOF-MS. A semiquantitative analysis of the peptides indicated that from the seven peptides containing sensitive amino acids, two peptides (HGLDNYR and WWCNDGR) were highly affected upon photo-oxidation and have the potential to serve as markers for protein oxidation. Site-specific modifications enabled the description of the degradation pathway of several lysozyme peptides but also indicated that the surrounding amino acids and the 3D structure of the protein have an impact on the induced modifications. It is therefore advisable to evaluate protein oxidation on the intact protein.
蛋白质氧化会对食品的质量和安全产生重大影响，但大多数评估氧化损伤的方法缺乏特异性。因此，本研究旨在确定蛋白质氧化的特异性标志物。通过光氧化修饰一种经过充分表征的蛋白质——溶菌酶，然后在 LC-TOF-MS 进行肽分析之前进行水解。对肽的半定量分析表明，在含有敏感氨基酸的七个肽中，有两个肽（HGLDNYR 和 WWCNDGR）在光氧化后受到高度影响，有可能作为蛋白质氧化的标志物。特异性修饰使我们能够描述几种溶菌酶肽的降解途径，但也表明周围的氨基酸和蛋白质的 3D 结构对诱导的修饰有影响。因此，建议在完整蛋白质上评估蛋白质氧化。
