Drake Henrik, Ivarsson Magnus, Bengtson Stefan, Heim Christine, Siljeström Sandra, Whitehouse Martin J, Broman Curt, Belivanova Veneta, Åström Mats E
Department of Biology and Environmental Science, Linnæus University, Kalmar, 39182, Sweden.
Department of Palaeobiology and Nordic Center for Earth Evolution (NordCEE), Swedish Museum of Natural History, P.O. Box 50 007, Stockholm, 10405, Sweden.
Nat Commun. 2017 Jul 4;8(1):55. doi: 10.1038/s41467-017-00094-6.
The deep biosphere is one of the least understood ecosystems on Earth. Although most microbiological studies in this system have focused on prokaryotes and neglected microeukaryotes, recent discoveries have revealed existence of fossil and active fungi in marine sediments and sub-seafloor basalts, with proposed importance for the subsurface energy cycle. However, studies of fungi in deep continental crystalline rocks are surprisingly few. Consequently, the characteristics and processes of fungi and fungus-prokaryote interactions in this vast environment remain enigmatic. Here we report the first findings of partly organically preserved and partly mineralized fungi at great depth in fractured crystalline rock (-740 m). Based on environmental parameters and mineralogy the fungi are interpreted as anaerobic. Synchrotron-based techniques and stable isotope microanalysis confirm a coupling between the fungi and sulfate reducing bacteria. The cryptoendolithic fungi have significantly weathered neighboring zeolite crystals and thus have implications for storage of toxic wastes using zeolite barriers.Deep subsurface microorganisms play an important role in nutrient cycling, yet little is known about deep continental fungal communities. Here, the authors show organically preserved and partly mineralized fungi at 740 m depth, and find evidence of an anaerobic fungi and sulfate reducing bacteria consortium.
深层生物圈是地球上最不为人所了解的生态系统之一。尽管该系统中的大多数微生物学研究都集中在原核生物上，而忽视了微型真核生物，但最近的发现揭示了海洋沉积物和海底下玄武岩中存在化石真菌和活性真菌，并提出它们对地下能量循环具有重要意义。然而，对深部大陆结晶岩中真菌的研究却出奇地少。因此，在这个广阔环境中真菌的特征、过程以及真菌与原核生物的相互作用仍然是个谜。在此，我们报告了在裂隙结晶岩深处（-740米）首次发现的部分有机保存和部分矿化的真菌。根据环境参数和矿物学特征，这些真菌被解释为厌氧型。基于同步加速器的技术和稳定同位素微分析证实了真菌与硫酸盐还原菌之间的耦合关系。隐生内生真菌对邻近的沸石晶体产生了显著的风化作用，因此对利用沸石屏障储存有毒废物具有重要意义。深部地下微生物在养分循环中起着重要作用，但对深部大陆真菌群落却知之甚少。在此，作者展示了在740米深处有机保存和部分矿化的真菌，并发现了厌氧真菌与硫酸盐还原菌共生的证据。
