通过N端截断增强终端脱氧核样转移酶的表达
An-Na Li1, Kun Shi1, Bu-Bing Zeng1
1State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Centre for Biomanufacturing, East China University of Science and Technology, Shanghai, China.
Biotechnology journal
|September 19, 2024
概括
终端脱核样转移酶 (TdT) 的N端截断显著提高了大肠杆菌中的蛋白质表达. 这一进步提高了无模板DNA合成的TdT实用性,并降低了生产成本.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 酵素工程是什么意思 酵素工程
背景情况:
- 终端脱核样转移酶 (TdT) 对于无模板的酶性DNA合成至关重要.
- 在大肠杆菌中表达脊椎动物TdTs在净化和成本效益方面存在挑战.
研究的目的:
- 改善脊椎动物衍生的TdTs的表达和稳定性.
- 研究N端截断对TdT功能和表达的影响.
主要方法:
- 对六种不同的TdT进行了N端截断.
- 分析了截断突变的蛋白质表达水平和催化活性.
- 测量了一个选定的突变体的热稳定性 (Tm).
主要成果:
- 切断N端增强了所有六个测试的TdT的表达.
- 特定突变 (N-140-ZaTdT和N-140-CpTdT) 的蛋白质表达分别高出9.5倍和23倍.
- 催化功能被保留,N-140-ZaTdT的热稳定性增加了4.9°C.
结论:
- 切断N端是改善TdT表达和稳定的有效策略.
- 截断的TdT更适合于具有成本效益的生产和酶工程应用.
- 这项工作促进了无模板DNA合成技术的进步.
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