Mesa Victoria, Gallego Jose L R, González-Gil Ricardo, Lauga Béatrice, Sánchez Jesús, Méndez-García Celia, Peláez Ana I
Department of Functional Biology - IUBA, University of OviedoOviedo, Spain.
Vedas Research and Innovation, Vedas CIIMedellín, Colombia.
Front Microbiol. 2017 Sep 12;8:1756. doi: 10.3389/fmicb.2017.01756. eCollection 2017.
Acid mine drainages are characterized by their low pH and the presence of dissolved toxic metallic species. Microorganisms survive in different microhabitats within the ecosystem, namely water, sediments, and biofilms. In this report, we surveyed the microbial diversity within all domains of life in the different microhabitats at Los Rueldos abandoned mercury underground mine (NW Spain), and predicted bacterial function based on community composition. Sediment samples contained higher proportions of soil bacteria (AD3, Acidobacteria), as well as Crenarchaeota and Methanomassiliicoccaceae archaea. Oxic and hypoxic biofilm samples were enriched in bacterial iron oxidizers from the genus , order Acidithiobacillales, class Betaproteobacteria, and archaea from the class Thermoplasmata. Water samples were enriched in Cyanobacteria and Thermoplasmata archaea at a 3-98% of the sunlight influence, whilst Betaproteobacteria, Thermoplasmata archaea, and Micrarchaea dominated in acid water collected in total darkness. Stalactites hanging from the Fe-rich mine ceiling were dominated by the neutrophilic iron oxidizer and other lineages that were absent in the rest of the microhabitats (e.g., Chlorobi, Chloroflexi). Eukaryotes were detected in biofilms and open-air water samples, and belonged mainly to clades SAR (Alveolata and Stramenopiles), and Opisthokonta (Fungi). Oxic and hypoxic biofilms displayed higher proportions of ciliates (), whereas water samples were enriched in fungi ( and unknown microbial Helotiales). Predicted function through bacterial community composition suggested adaptive evolutive convergence of function in heterogeneous communities. Our study showcases a broad description of the microbial diversity across different microhabitats in the same environment and expands the knowledge on the diversity of microbial eukaryotes in AMD habitats.
酸性矿山排水的特点是pH值低且存在溶解的有毒金属物种。微生物在生态系统的不同微生境中生存，即水、沉积物和生物膜。在本报告中，我们调查了西班牙西北部洛斯鲁埃尔多斯废弃汞地下矿山不同微生境中所有生命域内的微生物多样性，并根据群落组成预测细菌功能。沉积物样本中土壤细菌（AD3、酸杆菌）以及泉古菌门和甲烷微菌科古菌的比例较高。有氧和缺氧生物膜样本中富含嗜酸氧化亚铁硫杆菌属、嗜酸氧化亚铁硫杆菌目、β-变形菌纲的细菌铁氧化剂以及嗜热栖热菌纲的古菌。在受阳光影响3%-98%的水样中，蓝细菌和嗜热栖热菌纲古菌含量丰富，而在完全黑暗中采集的酸性水中，β-变形菌纲、嗜热栖热菌纲古菌和微小古菌占主导。悬挂在富含铁的矿井顶部的钟乳石主要由嗜中性铁氧化剂以及其他在其他微生境中不存在的谱系（如绿弯菌门、绿菌门）主导。在生物膜和露天水样中检测到真核生物，主要属于SAR进化枝（囊泡虫类和不等鞭毛类）以及后鞭毛生物（真菌）。有氧和缺氧生物膜中纤毛虫的比例较高，而水样中真菌（座囊菌纲和未知的柔膜菌目微生物）含量丰富。通过细菌群落组成预测的功能表明，异质群落中功能存在适应性进化趋同。我们的研究全面描述了同一环境中不同微生境的微生物多样性，并扩展了对酸性矿山排水生境中微生物真核生物多样性的认识。
