School of Environmental Science and Engineering, Shandong University, 27 Shanda South Road, Jinan 250100, People's Republic of China.
J Pept Sci. 2010 Mar;16(3):148-52. doi: 10.1002/psc.1212.
Biomarkers for peptide/protein oxidation under oxidative stress (OS) hold both incredible application potential as well as significant challenges. In this article, liquid chromatography and mass spectrometry were applied to establish a new method for evaluating the oxidation site and degree of peptide oxidized, with its oxidative product serving as biomarker. In the three model peptides, peptide FMRF (containing a methionine) was prone to undergo oxygen addition under UV/H(2)O(2) oxidization, forming a sulfoxide (FM(O)RF) with a stable chromatographic peak separate from the model peptides. The oxidation content of FMRF, expressed as S(FM(O)RF)/(S(FM(O)RF) + S(FMRF)), is positively correlated with oxidation time. Based on sequence analysis of FM(O)RF, the oxidation mechanism (site and extent) of FMRF under UV/H(2)O(2) oxidization was explicitly clarified. By comparing the specific injury to each model peptide, we found that the oxidative products of Met-containing peptides are good biomarkers for OS. This research not only expands the range of biomarkers for OS, but also provides an efficient and accurate method for evaluating oxidation damage to peptides and even proteins.
在氧化应激（OS）下，肽/蛋白质氧化的生物标志物具有令人难以置信的应用潜力和巨大的挑战。在本文中，应用液相色谱和质谱建立了一种新的方法来评估肽氧化的位置和程度，其氧化产物可作为生物标志物。在三个模型肽中，含有蛋氨酸的肽 FMRF 在 UV/H2O2 氧化下容易发生氧加成，形成一个与模型肽分离的稳定色谱峰的亚砜（FM（O）RF）。FMRF 的氧化含量，用 S（FM（O）RF）/（S（FM（O）RF）+S（FMRF））表示，与氧化时间呈正相关。根据 FM（O）RF 的序列分析，明确了 FMRF 在 UV/H2O2 氧化下的氧化机制（位置和程度）。通过比较每个模型肽的特定损伤，我们发现含 Met 肽的氧化产物是 OS 的良好生物标志物。这项研究不仅扩展了 OS 生物标志物的范围，而且为评估肽甚至蛋白质的氧化损伤提供了一种高效、准确的方法。
