在细菌的铁还原过程中,硫介导的电子穿
Theodore M Flynn1, Edward J O'Loughlin2, Bhoopesh Mishra3
1Biosciences Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA. Computation Institute, University of Chicago, Chicago, IL 60637, USA.
Science (New York, N.Y.)
|May 3, 2014
概括
在性条件下,微生物使用元素硫 (S(0) 来间接减少含水层中的铁 (Fe(III)). 这种S(0) 介导的途径对于铁循环至关重要,其中直接的微生物Fe(III) 减少被抑制.
科学领域:
- 生物地质化学生物地质化学
- 微生物生态学 微生物生态学
- 环境科学 环境科学
背景情况:
- 微生物降低铁酸铁[Fe (III) ]是无毒含水层中的一个关键过程.
- 溶解降解金属细菌可以在不同的地下水pH下利用像元素硫 (S(0) 这样的替代电子受体.
- 性条件在许多含水层系统中普遍存在,影响微生物呼吸.
研究的目的:
- 在性条件下研究铁和硫循环之间的相互作用.
- 了解当直接微生物呼吸受到限制时Fe (III) 减少的机制.
主要方法:
- 热力学地化学建模.热力学地化学建模.
- 使用细菌Shewanella oneidensis MR-1进行生物反应器实验.
- 在控制的性条件下分析微生物和地化学相互作用.
主要成果:
- 在性条件下,Shewanella oneidensis MR-1 酶降解了S(0) 但没有化 (α-FeOOH).
- 硫化物 (HS(-)) 由S(0) 降解而产生的非生物降解甲基.
- 这表明间接的Fe(III) 减少途径由S(0) 介导.
结论:
- 元素硫 (S(0)) 可以作为性含水层中Fe(III) 减少的电子运送器.
- 在铁的生态化学循环中,S(0) 介导的途径对于直接微生物Fe(III) 降解被抑制的铁生态化学循环具有重要意义.
- 这一发现对了解不同含水层环境中的生物地化学过程有重要意义.
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