Valeriani Federica, Crognale Silvia, Protano Carmela, Gianfranceschi Gianluca, Orsini Massimiliano, Vitali Matteo, Spica Vincenzo Romano
Laboratory of Epidemiology and Biotechnologies, University of Rome "Foro Italico", Rome, Italy.
Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo, Italy.
New Microbiol. 2018 Apr;41(2):126-135. Epub 2018 Mar 2.
Several factors influence bacteria biodiversity in hot springs. The impact of biotic and abiotic pathways on travertine deposition plays a key role in microbial ecology and in the final composition of the waterborne microbiota. The metabolism of some bacterial groups such as photoautotrophs or lithoautotrophs influences water chemistry, favoring carbonate precipitation processes. The role of microbial mats in mineral precipitation processes is not fully clarified. For the first time, a comprehensive metagenomic analysis has been undertaken in the historical Bullicame hot spring. Bacterial biodiversity was characterized and biomineralization activities were assigned to different genera. A higher biodiversity in mat samples compared to water samples was observed: Shannon index of 3.34 and 0.86, respectively. Based on the functional assignment of each Operational Taxonomic Unit, the bacteria involved in biologically- induced mineralization are prevalent in mat and released in the water. According to the principle that each geothermal water specimen has distinctive physic-chemical characteristics, our results suggest new interacting bio-actions within these ecosystems. The saturation index and the chemical composition, as the high concentration of sulfur species and HCO3, can be linked to create a selective environment where pioneer communities are able to live and shape the ecosystem.
有几个因素会影响温泉中的细菌生物多样性。生物和非生物途径对钙华沉积的影响在微生物生态学以及水生微生物群的最终组成中起着关键作用。一些细菌群体（如光合自养生物或化能自养生物）的代谢会影响水化学，有利于碳酸盐沉淀过程。微生物垫在矿物沉淀过程中的作用尚未完全阐明。首次在历史悠久的布利卡梅温泉进行了全面的宏基因组分析。对细菌生物多样性进行了表征，并将生物矿化活动归因于不同的属。观察到垫样中细菌生物多样性高于水样：香农指数分别为3.34和0.86。根据每个操作分类单元的功能分配，参与生物诱导矿化的细菌在垫中普遍存在并释放到水中。根据每个地热水样本具有独特理化特性的原理，我们的结果表明这些生态系统中存在新的相互作用的生物作用。饱和指数和化学成分，如高浓度的硫物种和HCO3，可以联系起来创造一个选择性环境，使先锋群落能够生存并塑造生态系统。
