PDF(Pubmed)
Abstract：
Important antioxidant enzymes, glutathione peroxidase (GPx) and superoxide dismutase (SOD), are involved in maintaining redox balance. They can protect each other and result in more efficiently removing excessive reactive oxygen species (ROS), protecting cells against injury, and maintaining the normal metabolism of ROS. In this study, human cytosolic GPx (hGPx1) and human phospholipid hydroperoxide GPx (hGPx4) genes were integrated into the same open reading frame with human extracellular SOD active site (SOD3-72P) genes, respectively, and several novel fusion proteins were obtained by using the UTuT6 expression system for the first time. Among them, Se-hGPx1UAG-L4-SOD3-72P is the bifunctional fusion protein with the highest GPx activity and the best anti-hydrogen peroxide inactivation ability thus far. The Se-hGPx4UAG-L3-SOD3-72P fusion protein exhibits the strongest alkali and high temperature resistance and a greater protective effect against lipoprotein peroxidation damage. Se-hGPx1UAG-L4-SOD3-72P and Se-hGPx4UAG-L3-SOD3-72P fusion proteins both have good synergistic and antioxidant abilities in H2O2-induced RBCs and liver damage models. We believe that this research will help with the development of novel bifunctional fusion proteins and the investigation of the synergistic and catalytic mechanisms of GPx and SOD, which are important in creating novel protein therapeutics.
摘要：
重要的抗氧化酶，谷胱甘肽过氧化物酶（GPx）和超氧化物歧化酶（SOD），参与维持氧化还原平衡。它们可以相互保护，并导致更有效地去除过量的活性氧（ROS），保护细胞免受伤害，维持ROS的正常代谢。在这项研究中,将人胞质GPx（hGPx1）和人磷脂过氧化氢GPx（hGPx4）基因整合到与人胞外SOD活性位点（SOD3-72P）基因相同的开放阅读框中，分别,并首次利用UTuT6表达系统获得了几种新型融合蛋白。其中,Se-hGPx1UAG-L4-SOD3-72P是迄今为止具有最高GPx活性和最佳抗过氧化氢灭活能力的双功能融合蛋白。Se-hGPx4UAG-L3-SOD3-72P融合蛋白表现出最强的耐碱性和耐高温性，并对脂蛋白过氧化损伤具有更大的保护作用。Se-hGPx1UAG-L4-SOD3-72P和Se-hGPx4UAG-L3-SOD3-72P融合蛋白在H2O2诱导的红细胞和肝损伤模型中均具有良好的协同和抗氧化能力。我们相信这项研究将有助于新型双功能融合蛋白的开发以及GPx和SOD的协同和催化机理的研究。这对创造新的蛋白质疗法很重要。
