生物能代谢的早期激活为细菌子发芽提供动力
Pooja Gupta1,2, Rebecca Caldbeck3, Rowan C Walters1,2
1York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom.
概括
细菌子发芽涉及电子运输链 (ETC) 的早期激活,独立于外部能量. 一种特定的氧化酶 (Yth) 在这个生物能量过程中起着关键作用.
科学领域:
- 微生物学 微生物学
- 细菌生理学 细菌生理学
- 生物能源学 生物能源学
背景情况:
- 细菌子可以在接触生长物时发芽到植物细胞中.
- 在子发芽期间的生物能量过程在很大程度上被忽视了.
- 即使没有外部能量来源,发芽也可以缓慢地发生.
研究的目的:
- 在细菌子发芽过程中非侵入性地测量电子输送链 (ETC) 的能量.
- 为了研究特定氧化酶在子发芽生物能学的作用.
- 提出一种动力细菌子发芽的模型.
主要方法:
- 缓解光谱的应用,以测量在发芽的Bacillus megaterium和Bacillus subtilis子中的ETC能量化.
- 对细胞质代谢和电子运输链能量化的分析.
- 研究了aa型氧化酶和bd氧化酶的Yth异型的作用.
- 研究了Yth删除对发芽启动的影响.
主要成果:
- 细胞质代谢和ETC的激活发生在发芽的早期,在水的吸收和CaDPA流量之前或与水的吸收和CaDPA流量一致.
- 3型氧化酶积聚铁中间体,其活性因高膜电位而减缓.
- 当aa型氧化酶受到阻碍时,Yth氧化酶促进了快速的电子转移到氧气中.
- 删除Yth显著减缓了发芽的开始.
结论:
- 生物能量过程,包括ETC能量化,是细菌子发芽的组成部分.
- 伊氏氧化酶在子发芽过程中发挥着至关重要的作用,因为它能够有效地转移电子.
- 提出了一个动力发芽模型,其中信号和生物能量是并行和相互依存的过程.
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