零价值硫是海洋甲氧化过程中的关键中间体
Jana Milucka1, Timothy G Ferdelman, Lubos Polerecky
1Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany.
Nature
|November 9, 2012
概括
海洋古生物可以通过形成零价值硫化合物独立进行甲无氧氧化 (AOM). 这一发现挑战了AOM作为一种有义务的合成过程,影响碳和硫循环的观点.
科学领域:
- 海洋微生物生态学
- 生物地质化学循环 生物地质化学循环
- 微生物的新陈代谢
背景情况:
- 海洋沉积物是甲的主要来源,甲是一种强大的温室气体.
- 甲无氧氧化 (AOM) 与硫酸盐减少相结合是甲排放的主要控制方法.
- 目前的理解表明,AOM是由甲类古生物 (ANME) 和硫酸盐降解型Deltaproteobacteria之间的合成合作关系介导的.
研究的目的:
- 阐明硫酸盐合甲 (AOM) 无氧氧化氧化的机制.
- 为了研究甲营养古生物 (ANME) 和Deltaproteobacteria在AOM中的作用.
- 探索硫转化中的新型微生物途径.
主要方法:
- 从海洋沉积物中研究的微生物联盟.
- 分析了参与甲无氧氧化 (AOM) 的代谢途径.
- 在AOM中确定了零价值的硫化合物 (S(0) 作为中间体.
主要成果:
- 甲类古生物 (ANME) 进行异样硫酸盐还原,产生零价值的硫化合物 (S(0)).
- AOM可以独立于Deltaproteobacteria发生,这挑战了义务合成模式.
- 相关的Deltaproteobacteria不成比例地将产生的S(0) 转化为二硫化物.
结论:
- 在ANME中发现了一种新的硫酸盐还原途径,扩大了已知的微生物硫转化.
- AOM可能不需要合成,而ANME可能单独起作用.
- 这些发现显著提升了我们对海洋碳和硫生物地质化学循环的理解.
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