Departamento de Biología Molecular, Universidad Autónoma de Madrid, c/Darwin 2, C-014/021, Campus de Cantoblanco, Crtra. de Colmenar, Km. 15, 28049, Madrid, Spain.
Extremophiles. 2012 Nov;16(6):829-39. doi: 10.1007/s00792-012-0478-4. Epub 2012 Sep 7.
The Tinto River (Huelva, Spain) is a natural acidic rock drainage environment produced by the bio-oxidation of metallic sulfides from the Iberian Pyritic Belt. A geomicrobiological model of the different microbial cycles operating in the sediments was recently developed through molecular biological methods, suggesting the presence of iron reducers, methanogens, nitrate reducers and hydrogen producers. In this study, we used a combination of molecular biological methods and targeted enrichment incubations to validate this model and prove the existence of those potential anaerobic activities in the acidic sediments of Tinto River. Methanogenic, sulfate-reducing, denitrifying and hydrogen-producing enrichments were all positive at pH between 5 and 7. Methanogenic enrichments revealed the presence of methanogenic archaea belonging to the genera Methanosarcina and Methanobrevibacter. Enrichments for sulfate-reducing microorganisms were dominated by Desulfotomaculum spp. Denitrifying enrichments showed a broad diversity of bacteria belonging to the genera Paenibacillus, Bacillus, Sedimentibacter, Lysinibacillus, Delftia, Alcaligenes, Clostridium and Desulfitobacterium. Hydrogen-producing enrichments were dominated by Clostridium spp. These enrichments confirm the presence of anaerobic activities in the acidic sediments of the Tinto River that are normally assumed to take place exclusively at neutral pH.
廷托河（西班牙韦尔瓦）是一种天然的酸性岩石排水环境，由伊比利亚黄铁矿带的金属硫化物的生物氧化产生。最近通过分子生物学方法开发了一个在沉积物中运行的不同微生物循环的地质微生物模型，表明存在铁还原剂、产甲烷菌、硝酸盐还原剂和氢生产者。在这项研究中，我们使用了分子生物学方法和靶向富集培养的组合来验证该模型，并证明在廷托河酸性沉积物中存在这些潜在的厌氧活性。在 pH 值为 5 到 7 之间，产甲烷、硫酸盐还原、反硝化和产氢的富集都是阳性的。产甲烷富集揭示了属于甲烷古菌属和甲烷短杆菌属的产甲烷古菌的存在。硫酸盐还原微生物的富集主要由脱硫梭菌属主导。反硝化富集显示了属于芽孢杆菌属、芽孢杆菌属、沉积物杆菌属、赖氨酸杆菌属、德氏菌属、产碱菌属、梭菌属和脱硫杆菌属的细菌的广泛多样性。产氢富集主要由梭菌属主导。这些富集证实了廷托河酸性沉积物中存在厌氧活性，这些活性通常被认为仅在中性 pH 值下发生。
