Prosenkov Alexander, Cagnon Christine, Gallego José Luis R, Pelaez Ana Isabel
Area of Microbiology, Department of Functional Biology, Environmental Biogeochemistry and Raw Materials Group and IUBA, University of Oviedo, 33006 Oviedo, Asturias, Spain.
Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Pau, France.
Environ Pollut. 2023 Apr 15;323:121305. doi: 10.1016/j.envpol.2023.121305. Epub 2023 Feb 16.
Abandoned brownfields represent a challenge for their recovery. To apply sustainable remediation technologies, such as bioremediation or phytoremediation, indigenous microorganisms are essential agents since they are adapted to the ecology of the soil. Better understanding of microbial communities inhabiting those soils, identification of microorganisms that drive detoxification process and recognising their needs and interactions will significantly improve the outcome of the remediation. With this in mind we have carried out a detailed metagenomic analysis to explore the taxonomic and functional diversity of the prokaryotic and eukaryotic microbial communities in soils, several mineralogically distinct types of pyrometallurgic waste, and groundwater sediments of a former mercury mining and metallurgy site which harbour very high levels of arsenic and mercury pollution. Prokaryotic and eukaryotic communities were identified, which turned out to be more diverse in the surrounding contaminated soils compared to the pyrometallurgic waste. The highest diversity loss was observed in two environments most contaminated with mercury and arsenic (stupp, a solid mercury condenser residue and arsenic-rich soot from arsenic condensers). Interestingly, microbial communities in the stupp were dominated by an overwhelming majority of archaea of the phylum Crenarchaeota, while Ascomycota and Basidiomycota fungi comprised the fungal communities of both stump and soot, results that show the impressive ability of these previously unreported microorganisms to colonize these extreme brownfield environments. Functional predictions for mercury and arsenic resistance/detoxification genes show their increase in environments with higher levels of pollution. Our work establishes the bases to design sustainable remediation methods and, equally important, to study in depth the genetic and functional mechanisms that enable the subsistence of microbial populations in these extremely selective environments.
废弃的棕地对其修复构成挑战。为了应用可持续修复技术，如生物修复或植物修复，本地微生物是至关重要的因素，因为它们适应土壤生态。更好地了解栖息在这些土壤中的微生物群落，识别驱动解毒过程的微生物并认识它们的需求和相互作用，将显著改善修复效果。考虑到这一点，我们进行了详细的宏基因组分析，以探索土壤、几种矿物学上不同类型的火法冶金废物以及一个曾经的汞矿开采和冶金场地的地下水沉积物中，原核和真核微生物群落的分类和功能多样性，这些场地含有极高水平的砷和汞污染。已识别出原核和真核群落，结果表明，与火法冶金废物相比，周围受污染土壤中的群落更加多样。在汞和砷污染最严重的两种环境（stupp，一种固态汞冷凝器残渣和来自砷冷凝器的富含砷的烟灰）中，观察到多样性损失最大。有趣的是，stupp中的微生物群落以奇古菌门的绝大多数古菌为主，而子囊菌门和担子菌门真菌构成了stupp和烟灰中的真菌群落，这些结果表明这些先前未报道的微生物具有在这些极端棕地环境中定殖的惊人能力。对汞和砷抗性/解毒基因的功能预测表明，在污染程度较高的环境中它们的数量会增加。我们的工作为设计可持续修复方法奠定了基础，同样重要的是，为深入研究使微生物种群在这些极具选择性的环境中生存的遗传和功能机制奠定了基础。
