This report describes acidic microbial mats containing cyanobacteria that are strongly associated to precipitated minerals in the source area of Río Tinto. Río Tinto (Huelva, Southwestern Spain) is an extreme acidic environment where iron and sulfur cycles play a fundamental role in sustaining the extremely low pH and the high concentration of heavy metals, while maintaining a high level of microbial diversity. These multi-layered mineral deposits are stable all year round and are characterized by a succession of thick greenish-blue and brownish layers mainly composed of natrojarosite. The temperature and absorbance above and below the mineral precipitates were followed and stable conditions were detected inside the mineral precipitates. Different methodologies, scanning and transmission electron microscopy, immunological detection, fluorescence in situ hybridization, and metagenomic analysis were used to describe the biodiversity existing in these microbial mats, demonstrating, for the first time, the existence of acid-tolerant cyanobacteria in a hyperacidic environment of below pH 1. Up to 0.46% of the classified sequences belong to cyanobacterial microorganisms, and 1.47% of the aligned DNA reads belong to the Cyanobacteria clade.

中文翻译：

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西班牙里奥廷托河酸性矿物沉淀物中 pH 值低于 1 的微生物群与耐酸蓝藻的关联

该报告描述了含有蓝细菌的酸性微生物垫，这些蓝细菌与力拓矿源区的沉淀矿物质密切相关。里奥廷托（西班牙西南部韦尔瓦）是一个极端酸性环境，铁和硫循环在维持极低的 pH 值和高浓度的重金属方面发挥着重要作用，同时保持高水平的微生物多样性。这些多层矿床全年稳定，其特点是有一系列厚的绿蓝色和棕色层，主要成分为钠铁钾石。跟踪矿物沉淀物上方和下方的温度和吸光度，并检测矿物沉淀物内部的稳定条件。使用不同的方法、扫描和透射电子显微镜、免疫检测、荧光原位杂交和宏基因组分析来描述这些微生物垫中存在的生物多样性，首次证明高酸性环境中耐酸蓝细菌的存在pH 低于 1。高达 0.46% 的分类序列属于蓝藻微生物，1.47% 的比对 DNA 读数属于蓝藻分支。