Pre-study to the deciphering of the cryptic microfossil Frutexites

叠层石富含铁的结构已经在许多古代环境中被报道，并且通常被解释为Frutexites，这是Maslov（1960）首次描述的一种神秘的微化石。虽然微生物形成是可能的，但缺乏与微生物前体的明确关系。我最初的微生物和生物化学调查最近Frutexites-like生物膜从瑞典的Äspö硬岩实验室揭示了细菌，古细菌，藻类和真菌的多样性复杂的社区的存在。因此，该项目的主要任务将是调查最近的几种生物膜，这些生物膜与化石Frutexites非常相似，并确定特征生物特征。最近的（活的）Frutexites样生物膜将从瑞典和德国的六个不同地点取样。这些Frutexites样品将进行显微镜和地球化学研究，并相互比较。该项目被设计为一个预先研究。如果结果是有希望的，一个更大的项目计划，在这项研究中确定的生物特征有助于确定来自不同地质时间尺度的现代和化石Frutexites的相似性，并评估其与古代铁循环的相关性。拟议项目的研究结果不仅与那些对生物特征感兴趣的人有关，而且与Frutexites，但预计将产生有趣的信息，微生物群落组成的细菌和真菌和重要的影响，研究生活在地下环境。

Stromatolitic iron-rich structures have been reported from many ancient environments and are often interpreted as Frutexites, a cryptic microfossil first described by Maslov (1960). Although a microbial formation is likely, a clear relation to a microbial precursor is lacking. My initial microbiological and biogeochemical investigations of recent Frutexites-like biofilms from the Äspö Hard Rock Laboratory in Sweden revealed the presence of a diverse complex community of bacteria, archaea, algae and fungi. Therefore, the major task of this project will be the investigation of several recent biofilms which are quite similar to the fossil Frutexites and to identify characteristic biosignatures. The recent (living) Frutexites-like biofilms will be sampled from six different locations in Sweden and Germany. These Frutexites samples will be microscopically and geochemically investigated and compared among each other. This project is designed as a pre-study. If the results are promising, a larger project is planned, where the biosignatures identified in this study help to determine similarities of recent and fossil Frutexites from different geological time scales and to evaluate their relevance for the ancient iron cycle.The research findings of the proposed project will not only be relevant for those interested in biosignatures, and Frutexites, but are expected to yield interesting information for microbial communities consisting of bacteria and fungi and important implications for studies on life in subsurface environments.