自从20世纪60年代开始，科学家就推测土壤中的细菌可以利用有传导性的物质来进行信息沟通，直到现在，这种说法依然是一种假设。就在两年前，丹麦的研究者发现了生存在海洋底部沉积物中的微生物可以和生存在海洋表面的微生物进行电子交流，这种做法可以使得其在海底获得足够的氧气以维持生存。
在最新的研究中，研究者发现了两种细菌：还原硫地杆菌和脱氮硫杆菌，这两种微生物可以利用乙酸盐和硝酸盐作为生物。为了深入研究者两种细菌，研究小组将其与导电磁铁矿混合，这将刺激细菌产生反应，两种细菌会将电子从一个传递至下一个，然后一起进行摄食，而且磁铁矿也只是细菌完成电子转移的一个介质。为了确定研究者的观察是否正确，研究小组不良导体生锈的红铁，研究发现细菌减慢了摄食的速度。当一个非导体混合入细菌中时，细菌就会停止共同的摄食。
因此研究人员基于结果推测，许多微生物可以在土壤中通过电子传递来进行相互交流，尽管电子传递是一个很小的行为，可是在细菌交流中却是非常重要的。那么细菌是如何依赖传导性物质来在土壤中进行定位以及电子传递的呢？目前并没有人知道这种机制是如何产生的，但是有些科学家表示，有可能是细菌可以促使电子链的产生以便不同细菌之间进行交流，尽管没有确切证据，但是研究者们正在竭尽全力去研究其机制的产生。
相关研究成果刊登在了国际著名杂志PNAS上。（生物谷Bioon.com）
编译自：Researchers show bacteria use natural materials to transfer electrons
编译者：天使托
doi:10.1073/pnas.1117592109
PMC:
PMID:
Microbial interspecies electron transfer via electric currents through conductive minerals
Souichiro Katoa,1, Kazuhito Hashimotoa,b,c,2, and Kazuya Watanabea,b,d,2
In anaerobic biota, reducing equivalents (electrons) are transferred between different species of microbes [interspecies electron transfer (IET)], establishing the basis of cooperative behaviors and community functions. IET mechanisms described so far are based on diffusion of redox chemical species and/or direct contact in cell aggregates. Here, we show another possibility that IET also occurs via electric currents through natural conductive minerals. Our investigation revealed that electrically conductive magnetite nanoparticles facilitated IET from Geobacter sulfurreducens to Thiobacillus denitrificans, accomplishing acetate oxidation coupled to nitrate reduction. This two-species cooperative catabolism also occurred, albeit one order of magnitude slower, in the presence of Fe ions that worked as diffusive redox species. Semiconductive and insulating iron-oxide nanoparticles did not accelerate the cooperative catabolism. Our results suggest that microbes use conductive mineral particles as conduits of electrons, resulting in efficient IET and cooperative catabolism. Furthermore, such natural mineral conduits are considered to provide ecological advantages for users, because their investments in IET can be reduced. Given that conductive minerals are ubiquitously and abundantly present in nature, electric interactions between microbes and conductive minerals may contribute greatly to the coupling of biogeochemical reactions.
