Brofft Jennifer E, McArthur J Vaun, Shimkets Lawrence J
Department of Microbiology, University of Georgia, Athens, GA 30602-2605, USA.
Environ Microbiol. 2002 Nov;4(11):764-9. doi: 10.1046/j.1462-2920.2002.00337.x.
Sulphide mineral mining together with improperly contained sulphur-rich coal represents a significant environmental problem caused by leaching of toxic material. The Savannah River Site's D-area harbours a 22-year-old exposed reject coal pile (RCP) from which acidic, metal rich, saline runoff has impacted an adjacent forested wetland. In order to assess the bacterial community composition of this region, composite sediment samples were collected at three points along a contamination gradient (high, middle and no contamination) and processed for generation of bacterial and archaeal 16S rDNA clone libraries. Little sequence overlap occurred between the contaminated (RCP samples) and unimpacted sites, indicating that the majority of 16S rDNAs retrieved from the former represent organisms selected by the acidic runoff. Archaeal diversity within the RCP samples consisted mainly of sequences related to the genus Thermoplasma and to sequences of a novel type. Bacterial RCP libraries contained 16S rRNA genes related to isolates (Acidiphilium sp., Acidobacterium capsulatum, Ferromicrobium acidophilium and Leptospirillum ferrooxidans) and environmental clones previously retrieved from acidic habitats, including ones phylogenetically associated with organisms capable of sulphur and iron metabolism. These libraries also exhibited particularly novel 16S rDNA types not retrieved from other acid mine drainage habitats, indicating that significant diversity remains to be detected in acid mine drainage-type systems.
硫化物矿物开采以及含有不当的富硫煤炭是由有毒物质浸出导致的重大环境问题。萨凡纳河工厂的D区有一个已有22年历史的露天废弃煤堆（RCP），富含酸性、金属且含盐的径流已对附近的森林湿地产生了影响。为了评估该区域的细菌群落组成，沿着污染梯度（高、中、无污染）在三个点采集了复合沉积物样本，并对其进行处理以构建细菌和古菌16S rDNA克隆文库。受污染的（RCP样本）和未受影响的位点之间几乎没有序列重叠，这表明从前一个位点检索到的大多数16S rDNA代表了由酸性径流选择的生物体。RCP样本中的古菌多样性主要由与嗜热栖热菌属相关的序列以及一种新型序列组成。细菌RCP文库包含与分离株（嗜酸菌属、嗜酸酸杆菌、嗜酸铁微菌和嗜酸氧化亚铁钩端螺旋菌）以及先前从酸性生境中检索到的环境克隆相关的16S rRNA基因，包括那些在系统发育上与能够进行硫和铁代谢的生物体相关的克隆。这些文库还展示了从其他酸性矿山排水生境中未检索到的特别新颖的16S rDNA类型，表明在酸性矿山排水类型系统中仍有大量多样性有待发现。
