吉奥巴克特 (Geobacter metallireducens) 通过化学反应获得不溶性铁氧化物
Susan E Childers1, Stacy Ciufo, Derek R Lovley
1Department of Microbiology, University of Massachusetts, Amherst 01003, USA.
Nature
|April 19, 2002
概括
当可溶性电子受体稀缺时,Geobacter metallireducens使用鞭毛和皮利来寻找不溶性氧化铁. 这种独特的策略使它能够获得水中沉积物中的必需营养.
科学领域:
- 微生物学 微生物学
- 环境科学 环境科学
- 生物修复是一种生物修复.
背景情况:
- 微生物利用不溶性Fe(III) 氧化物作为电子受体,影响水中沉积物的生物地球化学循环.
- 由于扩散的局限性,进入不溶性电子受体对微生物来说是一个挑战.
- 一些降低Fe (III) 的细菌,如Shewanella,使用可溶性金来弥合与Fe (III) 氧化物之间的距离.
研究的目的:
- 调查Geobactermetallireducens获得不溶性Fe (III) 氧化物的机制.
- 了解G.metallireducens在具有有限可溶电子受体的环境中的适应策略.
主要方法:
- 培养Geobacter金属减少不溶性Fe (III) 或Mn (IV) 氧化物.
- 在这些条件下观察鞭毛和皮利的表达.
- 对Fe (II) 和Mn (II) 的化学反应进行评估.
主要成果:
- 在不溶性Fe (III) 或Mn (IV) 氧化物上生长时,Geobacter metallireducens特别表达鞭和皮利.
- 当不溶性电子受体是主要来源时,细菌对Fe (II) 和Mn (II) 呈现化学反应.
- 这表明,对于耗尽的可溶性电子受体来说,有传感机制.
结论:
- 吉奥巴克特金属缩菌采用一种独特的策略,涉及移动性附属体,以定位和接触不溶性电子受体.
- 这种适应性行为可能解释了不同沉积环境中Geobacter物种的流行.
- 这些发现提供了关于微生物在具有挑战性的环境中获取营养和生物修复的策略的见解.
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