Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, 608 002, India.
Dharumapurm Gnanambikai Government Arts College, Dharumapuram Road, Nagapattinam, Mayiladuthurai, Tamil Nadu, 609001, India.
Arch Microbiol. 2020 Nov;202(9):2355-2366. doi: 10.1007/s00203-019-01729-6. Epub 2019 Sep 30.
The principal objective of this study is to determine the resistance of Deinococcus radiodurans to hydrogen peroxide (HO) induced oxidative stress by inhibiting its thioredoxin reductase (TrxR) antioxidant system. Treatment of D. radiodurans with different TrxR inhibitors such as ebselen, epigallocatechin gallate and auranofin displayed this organism sensitivity to HO treatment in a concentration-dependent manner. We observed that D. radiodurans showed greater resistance to HO treatment. Further, it has also been noticed that TrxR redox system was suppressed by TrxR inhibitors and that this response might be associated with the oxidative stress-mediated cell death in D. radiodurans. Thus, TrxR inhibitors affect the resistance of the D. radiodurans through suppression of its thioredoxin redox pathway via the inhibition of TrxR. Results from this study proved that TrxR plays an important role as an antioxidant enzyme by scavenging intracellular ROS, and thus contributing to the resistance of D. radiodurans towards oxidative stress.
本研究的主要目的是通过抑制耐辐射球菌的硫氧还蛋白还原酶 (TrxR) 抗氧化系统来确定其对过氧化氢 (HO) 诱导的氧化应激的抗性。用不同的 TrxR 抑制剂（如依布硒啉、表没食子儿茶素没食子酸酯和金诺芬）处理耐辐射球菌，观察到该生物体对 HO 处理的敏感性呈浓度依赖性。我们发现耐辐射球菌对 HO 处理表现出更强的抗性。此外，还注意到 TrxR 还原系统被 TrxR 抑制剂抑制，这种反应可能与耐辐射球菌中氧化应激介导的细胞死亡有关。因此，TrxR 抑制剂通过抑制 TrxR 抑制耐辐射球菌的硫氧还蛋白还原途径来影响其抗性。本研究的结果证明，TrxR 通过清除细胞内 ROS 作为抗氧化酶发挥重要作用，从而有助于耐辐射球菌抵抗氧化应激。
