西格玛因子RpoH的多复制表达减少了Serratia marcescens FS14中奇异的生物合成
Xuezheng Zhao1, Dongqing Xu1, Wenxiao Xia1
1Department of Microbiology, College of Life Sciences,, Nanjing Agricultural University, Nanjing, China.
Antonie van Leeuwenhoek
|September 20, 2023
概括
研究人员发现,增加的RpoH蛋白水平通过与RNA聚合酶的RpoS西格玛因子竞争来抑制prodigiosin生产. 这表明,准西格玛因子可以控制二次代谢物生产.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 作为二次代谢产物,Prodigiosin具有抗微生物,免疫抑制和抗癌特性,使其生物合成调节成为一个关键的研究领域.
- 了解prodigiosin生产的调节机制对于利用其治疗潜力至关重要.
研究的目的:
- 通过转子子子突变库,识别使用Serratia marcescens FS14中调节神奇素生物合成的基因.
- 为了研究rpoH基因在prodigiosin生产调节中的作用.
主要方法:
- 在Serratia marcescens FS14中建造和选一个转子子突变库.
- 转子子插入部位的识别.
- 对rpoH基因的删除突变分析.
- 使用多拷贝表达系统对基因表达的分析.
主要成果:
- 转子体突变基因确定了包括cyA,eepS/R和rpoH在内的基因,这些基因参与了神奇素生物合成调节.
- 删除rpoH没有影响prodigiosin的产生,但增强的RpoH表达减少了它.
- 增加的RpoH表达抑制了prodigiosin的产生,通过与RpoS西格玛因子竞争核心RNA聚合酶,减少猪基因集群转录.
结论:
- 在Serratia marcescens FS14中,RpoH通过干扰RpoS介导的转录来负面调节prodigiosin生物合成.
- 该研究强调了操纵西格玛因子水平以控制二次代谢物产生的潜力.
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