识别和表征Rgg1518的负调节器在Streptococcus pneumoniae中检测的质量检测
Duoyi Hu1, Irina Laczkovich2, Michael J Federle3,4
1Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA.
Journal of bacteriology
|June 21, 2023
概括
肺炎链球菌 (Streptococcus pneumoniae) 使用定数感应 (QS) 进行通信. 我们发现PepO酶降解SHP1518,抑制Rgg/SHP1518 QS信号传递,揭示了肺炎球菌毒性调节的关键机制.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌病原体的产生
背景情况:
- 肺炎 estreptococcus 导致人类的重大疾病,包括肺炎,脑膜炎和中耳炎.
- 定数感应 (QS) 是S. pneumoniae中关键的细胞间通信机制,调节基因表达和毒性.
- Rgg/SHP1518 QS系统是S. pneumoniae中发现的多个系统之一,但其监管网络和健康贡献需要进一步阐明.
研究的目的:
- 为了研究D39基因组中的Rgg同类基因的调控活动.
- 为了理解spd_1513-1517操作的收调节.
- 为了确定 Rgg/SHP1518 QS 系统的上游调节器.
主要方法:
- 对六种QS调节器突变的转录组分析.
- 转子体突变发生的查,以确定上游调节者.
- 酶活性测定和位点定向突变发生,以表征PepO功能.
主要成果:
- 至少有四个QS调节器影响spd_1513-1517操作子的表达,由Rgg/SHP1518.控制.
- 在pePO和spxB突变体中插入的转子导致Rgg1518-依赖转录的增加.
- 肺炎球菌PepO被确定为一种金属内酶,降解SHP1518,抑制Rgg/SHP1518QS激活,在其催化域中对谷氨酸残留具有关键作用.
结论:
- 多个Rgg监管机构汇聚在控制Rgg/SHP1518 QS系统上.
- 通过降解其信号分子,PepO作为Rgg/SHP1518 QS的负调节剂.
- 这项研究阐明了S. pneumoniae中QS调节的新机制,突出了PepO在控制毒性因子表达中的作用.
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