Novel Insights into Organophosphorus-Mineralizing Bacteria Expediting Uranate Immobilization in Tailings

Here, we combined gene amplicon sequencing, metagenomics, metatranscriptomics with strain isolation to explore the effect of PSB on AP and uranate in mining lands. We found that the content of AP and exchangeable U in tailings was significantly higher than their adjacent soils. Surprisingly, PhoD-harboring and gcd-harboring bacteria were enriched in tailings and soils, but only PhoD-harboring bacteria substantially contributed to the AP. Also, the most genes involved in organophosphorus mineralization and uranate resistance were widely present in tailings rather than soils. This study reveals a synergetic metabolic pathway of uranate immobilization by PSB-driven organophosphorus mineralization and highlights the importance of PSB to P and U biogeochemistry in U tailings.

本研究整合基因扩增子测序（gene amplicon sequencing）、宏基因组学（metagenomics）、宏转录组学（metatranscriptomics）与菌株分离技术，旨在探究溶磷菌（Phosphate-solubilizing bacteria, PSB）对矿区尾矿中有效磷（available phosphorus, AP）与铀酸盐的影响。研究发现，尾矿中的有效磷与可交换态铀含量显著高于其毗邻土壤。令人意外的是，携带PhoD与gcd基因的细菌在尾矿与土壤中均发生富集，但仅携带PhoD基因的细菌对有效磷含量提升具有实质性贡献。此外，参与有机磷矿化与铀酸盐抗性的绝大多数功能基因在尾矿中广泛分布，而非毗邻土壤。本研究揭示了溶磷菌驱动有机磷矿化进而介导铀酸盐固定的协同代谢途径，并凸显了溶磷菌在铀尾矿磷与铀生物地球化学循环中的关键作用。