Bioprocess Engineering Group, Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
Int J Biol Macromol. 2021 Sep 30;187:373-385. doi: 10.1016/j.ijbiomac.2021.07.150. Epub 2021 Jul 27.
Superoxide dismutases (SODs) (EC 1.15.1.1) are well known antioxidant enzymes that play critical roles in cellular defenses of living organisms against harmful superoxide radicals during oxidative stress. This study details on cloning, biochemical and functional characterization of an iron containing type superoxide dismutase (SOD) from a novel thermophilic bacteria Cohnella sp. A01 (CaSOD). The secondary and three dimensional structure of the protein were predicted. CaSOD gene was subsequently cloned into pET-26b(+) expression vector and expression of the recombinant protein (rCaSOD) was optimized in E. coli BL21 (DE3) and the purified recombinant SOD showed a single band with an apparent molecular weight of 26 kDa by SDS-PAGE. The half-life and thermodynamic parameters including ΔH, ΔS, and ΔG were 187 min at 60 °C, 7.3 kJ.mol, -76.8 kJ.mol.°K, and 84.1 kJ.mol, respectively. The rCaSOD exhibited catalytic activity in a very broad range of pH (6.0-10.0) and temperatures (35-75 °C), as well as stability in a broad pH range, from 3.0 to 11.0, and wide range of temperature, different concentrations of detergent agents, metal ions, organic solvents and other chemicals. The results suggest that this novel enzyme could be used for various industrial applications in cosmetic, food, and pharmaceutical industries.
超氧化物歧化酶（SODs）（EC 1.15.1.1）是众所周知的抗氧化酶，在生物体的细胞防御中起着关键作用，可抵御氧化应激过程中有害的超氧自由基。本研究详细介绍了一种新型嗜热细菌 Cohnella sp. A01（CaSOD）中含铁型超氧化物歧化酶（SOD）的克隆、生化和功能特性。预测了该蛋白质的二级结构和三维结构。CaSOD 基因随后被克隆到 pET-26b(+)表达载体中，在大肠杆菌 BL21(DE3)中优化了重组蛋白（rCaSOD）的表达，SDS-PAGE 显示纯化的重组 SOD 有一条单带，表观分子量为 26 kDa。半衰期和热力学参数包括在 60°C 时的 187 min、7.3 kJ/mol、-76.8 kJ/mol·K 和 84.1 kJ/mol。rCaSOD 在非常宽的 pH（6.0-10.0）和温度（35-75°C）范围内具有催化活性，并且在很宽的 pH 范围内稳定，从 3.0 到 11.0，以及在很宽的温度范围内，不同浓度的去污剂、金属离子、有机溶剂和其他化学物质。结果表明，这种新型酶可用于化妆品、食品和制药行业的各种工业应用。
