一个出口的可以在细胞内发挥作用,为B. subtilis细胞密度信号提供贡献
B A Lazazzera1, J M Solomon, A D Grossman
1Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA.
Cell
|June 13, 1997
概括
信号PhrA和CSF调节了Bacillus subtilis的能力和运动. 功能性研究表明,这些需要细胞进口,其中CSF利用寡透酶 (Opp) 载体.
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:
- 细菌的竞争力和分泌是Bacillus subtilis的关键发育途径.
- 这些过程由细胞外信号调节,这些在高细胞密度生长过程中积累起来.
- 了解这些介导信号是破译细菌发育控制的关键.
研究的目的:
- 研究B. subtilis. 中PhrA和CSF信号的功能和运输.
- 为了确定成熟的信号是否在细胞内起作用,需要进口.
- 阐明CSF运输的机制及其依赖于集中的活动.
主要方法:
- 基因构造以细胞内表达成熟的PhrA和CSF.
- 对能力发展和运动的表型分析.
- 在生理学度下使用CSF进行氧透酶 (Opp) 运输测定.
- 对CSF对基因表达活动的剂量反应分析.
主要成果:
- 表达的成熟五 (PhrA和CSF) 是细胞内功能性的,这表明需要进口.
- 脑脊液通过10nM的寡透酶 (Opp) 转移到B. subtilis细胞中.
- 在不同度下,CSF表现出不同的活性:在低度下刺激能力,在高度下抑制能力,同时刺激运动.
结论:
- B. subtilis信号PhrA和CSF需要细胞进口来发挥它们的功能.
- 寡聚透酶 (Opp) 系统负责将CSF运输到细胞中.
- 在B. subtilis的发展过程中,CSF表现出复杂的,依赖于度的监管作用,影响了竞争力和运动量.
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