The present study aimed to unveil potential protective mechanisms of SEPS-4, a novel sulfated derivative of exopolysaccharide produced by Enterobacter cloacae Z0206, against H₂O₂-induced oxidative damage in murine macrophages based on proteomic approaches. SEPS-4 pre-treatment was found to be capable of alleviating H₂O₂-induced reduction of RAW264.7 cell viability. Two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were used to evaluate proteins with significant expression alterations in H₂O₂-challenged RAW264.7 cells following pre-incubation with SEPS-4. Here 12 up-regulated proteins and 12 down-regulated proteins were successfully identified. Bio-informatic analysis was applied for further mechanistic studies. GO annotation and KEGG pathway enrichment analyses demonstrated that differentially expressed proteins were mainly clustered in stress-related biological processes, including metabolic process, stimulus to response, cell growth and death. Peroxiredoxin-2 and Eef1g were core modules of protein-protein interaction network. Collectively, our data indicated that SEPS-4 may exert protective effects against H₂O₂-induced oxidative damage via the regulation of these functional proteins and related biological processes.

本研究旨在揭示SEPS-4的潜在保护机制，这是一种由阴沟肠杆菌Z0206产生的新型胞外多糖硫酸盐衍生物，基于蛋白质组学方法对H ₂ O ₂诱导的小鼠巨噬细胞氧化损伤的保护作用。发现SEPS-4预处理能够减轻H ₂ O ₂诱导的RAW264.7细胞活力的降低。二维凝胶电泳和基质辅助激光解吸/电离飞行时间质谱用于评估H ₂ O _2中表达明显改变的蛋白质与SEPS-4预温育后，可攻击RAW264.7细胞。在这里成功鉴定出12种上调蛋白和12种下调蛋白。生物信息学分析被用于进一步的机理研究。GO注释和KEGG途径富集分析表明差异表达的蛋白质主要集中在应激相关的生物过程中，包括代谢过程，对反应的刺激，细胞生长和死亡。Peroxiredoxin-2和Eef1g是蛋白质-蛋白质相互作用网络的核心模块。总体而言，我们的数据表明，SEPS-4可能通过调节这些功能蛋白和相关的生物学过程而对H ₂ O ₂引起的氧化损伤发挥保护作用。