Metabolically active microbial communities in uranium-contaminated subsurface sediments
Metabolically active microbial communities in uranium-contaminated subsurface sediments
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DOI：
10.1111/j.1574-6941.2006.00203.x
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发表时间：
2007-01-01
影响因子：
4.2
通讯作者：
Kostka, Joel E.
中科院分区：
文献类型：
--
作者：
Akob, Denise M.;Mills, Heath J.;Kostka, Joel E.
为了制定有效的放射性核素污染物的生物修复策略，微生物群落的组成和代谢潜力需要得到更好的理解，特别是在高度污染的地下沉积物，很少培养独立的信息。在这项研究中，我们的特点是代谢活性和总微生物群落与铀污染的地下沉积物沿着地球化学梯度。DNA和RNA的提取和扩增从四个沉积物的深度区间代表中度酸性（pH 3.7），近中性（pH 6.7）的条件。在DNA和RNA衍生的克隆文库中检测到与变形菌门（α-、β-、δ-和γ-变形菌门）、拟杆菌门、放线菌门、厚壁菌门和浮游菌门相关的系统型。多样性和数量优势的沉积物的地球化学和微生物活性的变化，这表明地球化学条件选择了适应良好的类群。序列密切相关的硝酸盐还原菌代表28%和43%的克隆从总的微生物群落的代谢活性组分，分别。这项研究提供了第一个详细分析放射性核素污染的地下沉积物中的总微生物群落和代谢活性微生物群落。我们的微生物群落分析，结合微生物活性率，指出几组硝酸盐还原剂，似乎是很好地适应环境条件下常见的放射性核素污染的网站。
In order to develop effective bioremediation strategies for radionuclide contaminants, the composition and metabolic potential of microbial communities need to be better understood, especially in highly contaminated subsurface sediments for which little cultivation-independent information is available. In this study, we characterized metabolically active and total microbial communities associated with uranium-contaminated subsurface sediments along geochemical gradients. DNA and RNA were extracted and amplified from four sediment-depth intervals representing moderately acidic (pH 3.7) to near-neutral (pH 6.7) conditions. Phylotypes related to Proteobacteria (Alpha-, Beta-, Delta- and Gammaproteobacteria), Bacteroidetes, Actinobacteria, Firmicutes and Planctomycetes were detected in DNA- and RNA-derived clone libraries. Diversity and numerical dominance of phylotypes were observed to correspond to changes in sediment geochemistry and rates of microbial activity, suggesting that geochemical conditions have selected for well-adapted taxa. Sequences closely related to nitrate-reducing bacteria represented 28% and 43% of clones from the total and metabolically active fractions of the microbial community, respectively. This study provides the first detailed analysis of total and metabolically active microbial communities in radionuclide-contaminated subsurface sediments. Our microbial community analysis, in conjunction with rates of microbial activity, points to several groups of nitrate-reducers that appear to be well adapted to environmental conditions common to radionuclide-contaminated sites.