Faculté des Sciences, Université de Rouen, CNRS UMR 6143-M2C, Groupe de Microbiologie, Place Emile Blondel, 76821 Mont Saint Aignan Cedex, France.
Mar Pollut Bull. 2012 Oct;64(10):2135-45. doi: 10.1016/j.marpolbul.2012.07.042. Epub 2012 Aug 24.
We studied the abundance and diversity of the sulfate-reducing prokaryotes (SRPs) in two 30-cm marine chilean sediment cores, one with a long-term exposure to copper-mining residues, the other being a non-exposed reference sediment. The abundance of SRPs was quantified by qPCR of the dissimilatory sulfite reductase gene β-subunit (dsrB) and showed that SRPs are sensitive to high copper concentrations, as the mean number of SRPs all along the contaminated sediment was two orders of magnitude lower than in the reference sediment. SRP diversity was analyzed by using the dsrB-sequences-based PCR-DGGE method and constructing gene libraries for dsrB-sequences. Surprisingly, the diversity was comparable in both sediments, with dsrB sequences belonging to Desulfobacteraceae, Syntrophobacteraceae, and Desulfobulbaceae, SRP families previously described in marine sediments, and to a deep branching dsrAB lineage. The hypothesis of the presence of horizontal transfer of copper resistance genes in the microbial population of the polluted sediment is discussed.
我们研究了两个 30 厘米长的智利海洋沉积物岩芯中硫酸盐还原菌（SRP）的丰度和多样性，一个岩芯长期暴露于铜矿尾矿中，另一个为未暴露的参考沉积物。通过脱硫弧菌 β 亚基（dsrB）基因的 qPCR 定量了 SRP 的丰度，结果表明 SRP 对高铜浓度敏感，因为受污染沉积物中 SRP 的平均数量比参考沉积物低两个数量级。通过基于 dsrB 序列的 PCR-DGGE 方法和构建 dsrB 序列的基因文库分析了 SRP 的多样性。令人惊讶的是，两个沉积物中的多样性相当，dsrB 序列属于 Desulfobacteraceae、Syntrophobacteraceae 和 Desulfobulbaceae，这是先前在海洋沉积物中描述的 SRP 家族，以及一个深分支的 dsrAB 谱系。讨论了在污染沉积物的微生物种群中存在铜抗性基因水平转移的假说。
