好氧和厌氧条件下Acidithiobacillus ferrooxidans菌对Fe3+氧化FeS2的影响

摘要

嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans：A. ferrooxidans菌)是目前研究得最多的浸矿细菌，其能量代谢途径复杂多样。在好氧和厌氧气氛下，分别对Fe3+浸出黄铁矿及A. ferrooxidans菌对Fe3+氧化浸出黄铁矿的影响进行了研究，并且利用A. ferrooxidans菌构建微生物燃料电池，研究在不同气氛下A. ferrooxidans菌对电子传递过程的影响。结果表明：在好氧和厌氧气氛下，加菌时的黄铁矿浸出率比无菌时的分别提高了40.03%和27.76%。在好氧和厌氧气氛下，A. ferrooxidans菌均可以提高电子传递速率，进而加快氧化还原反应的进行，说明A. ferrooxidans菌在厌氧环境下，能以Fe3+为电子受体、含还原性硫的黄铁矿为电子供体来进行呼吸作用，获得生命活动所需的能量。在实验结果和前人工作的基础上提出在厌氧情况下，A. ferrooxidans 菌进行呼吸作用的一条可能的路线图。%Acidithiobacillus ferrooxidans (A. ferrooxidans) is the most widely studied bacteria, which is used in leaching ores work. The pyrite leached by ferric iron and the effect of A. ferrooxidans on pyrite leaching were studied under the aerobic and anaerobicatmosphere,respectively. Bio­cathode microbial fuel cells were constructed in accordance with the characteristics of A. ferrooxidans, and then used to study the effect of A. ferrooxidans on the electron transfer process under the aerobic and anaerobic atmosphere. The results show that, under the aerobic and anaerobic atmosphere, the leaching rates of pyrite are 40.03%and 27.76%more than those of chemical leaching, respectively. Under the aerobic and anaerobic atmosphere, the presence of A. ferrooxidans both can improve the electron transfer rate, and thus speed up the conduct of the redox reaction. This demonstrates that, in the anaerobic environment, A. ferrooxidans can be respiration using Fe3+as electron acceptor and pyrite containing reduced sulfur as electron donor. On the basis of experimental results and previous work, a possible electron transport chain of A. ferrooxidans under anaerobic condition was proposed.