National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow, UP 226001, India.
Biotechnol Lett. 2011 Oct;33(10):2057-63. doi: 10.1007/s10529-011-0670-0. Epub 2011 Jun 22.
A gene from Withania somnifera (winter cherry), encoding a highly stable chloroplastic Cu/Zn superoxide dismutase (SOD), was cloned and expressed in Escherichia coli. The recombinant enzyme (specific activity of ~4,200 U mg(-1)) was purified and characterized. It retained ~90 and ~70% residual activities after 1 h at 80 and 95 °C, respectively. At 95 °C, thermal inactivation rate constant (K (d)) of the enzyme was 2.46 × 10(-3) min(-1) and half-life of heat inactivation was 4.68 h. The enzyme was stable against a broad pH range (2.5-11.0). It also showed a high degree of resistance to detergent, ethanol and protease digestion. This recombinant Cu/Zn SOD could therefore have useful applications.
从冬樱桃（Withania somnifera）中克隆并在大肠杆菌中表达了一种编码高度稳定的叶绿体 Cu/Zn 超氧化物歧化酶（SOD）的基因。该重组酶（比活性约为 4200 U mg(-1)）被纯化并进行了表征。它在 80 和 95°C 下分别保持约 90%和 70%的残余活性。在 95°C 下，该酶的热失活动力学常数（K (d)）为 2.46×10(-3) min(-1)，热失活半衰期为 4.68 h。该酶在较宽的 pH 范围（2.5-11.0）下稳定。它还对去污剂、乙醇和蛋白酶消化具有很高的抗性。因此，这种重组 Cu/Zn SOD 可能具有有用的应用。
