Abstract：
Secondary iron-sulfate minerals such as jarosite, which are easily formed in acid mine drainage, play an important role in controlling metal mobility. In this work, the typical iron-oxidizing bacterium Acidithiobacillus ferrooxidans ATCC 23270 was selected to synthesize jarosite in the presence of antimony ions, during which the solution behavior, synthetic product composition, and bacterial metabolism were studied. The results show that in the presence of Sb(V), Fe2+ was rapidly oxidized to Fe3+ by A. ferrooxidans and Sb(V) had no obvious effect on the biooxidation of Fe2+ under the current experimental conditions. The presence of Sb(III) inhibited bacterial growth and Fe2+ oxidation. For the group with Sb(III), products with amorphous phases were formed 72 hr later, which were mainly ferrous sulfate and pentavalent antimony oxide, and the amorphous precursor was finally transformed into a more stable crystal phase. For the group with Sb(V), the morphology and structure of jarosite were changed in comparison with those without Sb. The biomineralization process was accompanied by the removal of 94% Sb(V) to form jarosite containing the Fe-Sb-O complex. Comparative transcriptome analysis shows differential effects of Sb(III) and Sb(V) on bacterial metabolism. The expression levels of functional genes related to cell components were much more downregulated for the group with Sb(III) but much more regulated for that with Sb(V). Notably, cytochrome c and nitrogen fixation-relevant genes for the A.f_Fe2+_Sb(III) group were enhanced significantly, indicating their role in Sb(III) resistance. This study is of great value for the development of antimony pollution control and remediation technology.
摘要：
次生硫酸铁矿物，如黄铁矿，在酸性矿井排水中很容易形成，在控制金属流动性方面发挥着重要作用。在这项工作中,选择典型的铁氧化细菌嗜酸氧化亚铁硫杆菌ATCC23270在锑离子存在下合成黄钾铁酸盐，在此期间，解决方案行为，合成产品组成，和细菌代谢进行了研究。结果表明,在Sb(V)存在下,Fe2+被A.氧化亚铁合金快速氧化为Fe3+，在目前的实验条件下，Sb(V)对Fe2+的生物氧化没有明显影响。Sb（III）的存在抑制了细菌生长和Fe2氧化。对于具有Sb（III）的基团，72小时后形成非晶相的产品，主要是硫酸亚铁和五价氧化锑，非晶前驱体最终转变为更稳定的晶相。对于具有Sb（V）的基团，与不含Sb的铁盐相比，铁盐的形态和结构发生了变化。生物矿化过程伴随着94％Sb（V）的去除，形成含有Fe-Sb-O络合物的黄钾铁酸盐。比较转录组分析显示Sb（III）和Sb（V）对细菌代谢的不同影响。对于Sb（III）组，与细胞成分相关的功能基因的表达水平下调得多，而对于Sb（V）组，则下调得多。值得注意的是,A.f_Fe2+_Sb(Ⅲ)组细胞色素c和固氮相关基因显著增强,表明它们在Sb(III)抗性中的作用。该研究对发展锑污染控制和修复技术具有重要价值。
