卡洛巴克特的NtrB-NtrC两组系统弥合了同化和细胞发育的桥梁
Hunter North1, Maeve McLaughlin1, Aretha Fiebig1
1Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan USA.
bioRxiv : the preprint server for biology
|June 19, 2023
概括
考洛巴克特NtrC是一种细菌增强剂结合蛋白,调节代谢和细胞发育. 失去NtrC会影响生长和多糖合成,揭示了它在Caulobacter形态发生和进化中的作用.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌生理学 细菌生理学
背景情况:
- 考洛巴克特使用分子感觉系统来控制生长和发育.
- 对于NtrC和NtrB在Caulobacter代谢和发育中的作用尚不清楚.
- 考洛巴克特NtrC是一种非常规的细菌增强剂结合蛋白,缺乏典型的σ54相互作用的GAFTGA基因.
研究的目的:
- 为了研究NtrC和NtrB在Caulobacter crescentus中的功能.
- 阐明NtrC在同化,细胞循环和发育中的调节作用.
- 探索NtrC对细胞外多糖合成和形态生成的影响.
主要方法:
- 在Caulobacter crescentus中对ntrC和ntrB突变的遗传分析.
- 在各种源下评估细胞生长.
- 使用ChIP-seq或类似技术识别NtrC直接结合点.
- 在突变菌株中分析细胞形态和多糖含量.
主要成果:
- 删除ntrC会减缓复杂介质的生长,而ntrB/ntrC对于作为唯一源的生长至关重要.
- 移动元素转换IS3家族可以通过恢复glnBA操作子转录来拯救ntrC生长缺陷.
- NtrC直接与染色体上的许多位点结合,许多靠近多糖生物合成基因.
- NtrC的结合部位与GapR和MucR1的结合部位重叠,这表明它们在细胞周期和发育调节中的作用.
- 丧失NtrC功能会导致长长的极地茎和细胞外多糖化合物合成的增加.
结论:
- 在Caulobacter中,NtrC对谷氨酸合成酶表达和同化至关重要.
- 在营养限制下,IS3转移可能在Caulobacter进化中发挥作用.
- NtrC直接调节参与细胞循环和发育的基因,影响极性形态发生和多糖合成.
- 这项研究确立了NtrC,代谢和Caulobacter发育中的细胞外多糖化合物合成之间的联系.
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