DNA结合蛋白Dps 保护大肠杆菌细胞在干燥过程中免受多重压力
Nataliya Loiko1, Ksenia Tereshkina2, Vladislav Kovalenko2
1Winogradsky Institute of Microbiology, Fundamentals of Biotechnology Federal Research Center, Russian Academy of Sciences, 117312 Moscow, Russia.
Biology
|June 28, 2023
概括
过度表达DNA结合蛋白Dps的细菌细胞在干燥应激后的生存率显著更高. 这种蛋白质增强了细胞在细胞外基质中的保护和固定,这对于干燥和再水期间的生存至关重要.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 生物技术是生物技术.
背景情况:
- 细菌细胞在自然环境和工业应用中面临致命的干燥压力.
- 生存机制涉及复杂的分子,生理和结构重组,其中蛋白质起着关键作用.
- 众所周知,DNA结合蛋白Dps可以保护细胞免受各种压力.
研究的目的:
- 为了研究DNA结合蛋白Dps (也称为饥饿细胞中的DNA结合蛋白) 在干燥压力下的细菌细胞中的保护作用.
- 为了量化工程 *E. coli* 过度表达 Dps 的生存率,在再水后.
- 阐明DPS介导的干燥耐受性背后的结构和分子机制.
主要方法:
- 针对Dps蛋白过度产生的大肠杆菌*的工程遗传模型.
- 干燥和再水实验,以评估细胞活力.
- 扫描电子显微镜 (SEM) 和传输电子显微镜 (TEM) 用于细胞形态学和晶体结构分析.
- 对DNA-Dps共晶体的粗粒度分子动力学模拟.
主要成果:
- 在大肠杆菌中,dps蛋白质的过度产生的结果是,在再水后,可活细胞标位增加了1.5-8.5倍.
- 在Dps过度表达细胞中,SEM在补水后揭示了细胞形态的改变.
- 随着Dps的过度生产,观察到细胞外基质内的固定性增加,与增强的生存率相关.
- 在干燥和再水化的细胞中,TEM显示了DNA-Dps晶体结构的破坏.
- 分子动力学模拟证实了Dps在干燥过程中在DNA-Dps共晶体中的保护作用.
结论:
- 通过促进固定和保护DNA,DPS蛋白显著提高了在干燥压力下细菌的生存率.
- 了解DPS的功能对于提高细菌细胞在生物技术过程中的弹性至关重要.
- 这项研究为细菌耐干燥的分子机制提供了新的见解.
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