[大肠杆菌和细菌细菌表达系统对生产双酶突变的效率]
A I Nadyrova1,2, A S Kosnyrev1, V V Ulyanova1
1Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, 420008 Russia.
Molekuliarnaia biologiia
|September 27, 2023
概括
虫杆菌的核糖核酶 (双酶) 突变体具有减少的催化活性,显示出对癌症治疗的潜力. 与His101Glu突变物不同,Lys26Ala突变物保留了抗瘤特性,毒性较低.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 生物技术是生物技术.
背景情况:
- 虫杆菌核糖核酶 (二酶) 具有细胞毒性和瘤毒性,但在高度时可以引起基因毒性.
- 开发具有减少催化活性的双酶突变可以减轻有毒副作用,同时保持抗瘤功效.
研究的目的:
- 为潜在的癌症治疗创造和描述具有减少催化活性的双酶突变体.
- 为了比较双酶突变体与瘤细胞系的疗效和毒性.
主要方法:
- 用于产生Lys26Ala和His101Glu双酶突变的方法是局部定向的突变发生.
- 对突变产生的大肠杆菌和细菌细菌表达系统的比较分析.
- 通过离子交换染色学净化突变物,并评估对RNA基质的催化活性.
- 对各种瘤和正常细胞系进行细胞毒性测定.
主要成果:
- 细菌细菌的表达系统产生了更高的双酶突变的产生 (高达25毫克/升).
- Lys26Ala突变体表现出11%的本源双酶催化活性;His101Glu突变体显示出0.02%.
- Lys26Ala突变体对A549,BT-20和HuTu 80瘤细胞表现出细胞毒性,但没有伤害正常的WI-38细胞.
- 他的101Glu突变缺乏显著的细胞毒性.
结论:
- 这种Lys26Ala双酶突变保留了解性质,具有减少的催化活性和较低的毒性,表明了治疗潜力.
- 细菌细菌的表达系统适合产生双酶突变.
- 对二酶突变的进一步研究可能会导致更安全,更有效的癌症治疗方法.
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