Volatilization and Recovery of Mercury from the Mercury-Polluted Soil Using Mercury-Resistant Strains of Acidithiobacillus ferrooxidans

氧化亚铁硫杆菌存在于酸性矿山的排水中，在硫化矿石的细菌浸出中起着至关重要的作用。低品位矿石的微生物浸出需要在重金属种类多、浓度高的环境中具有较高的氧化铁活性的氧化亚铁杆菌。从150株自然环境中分离的氧化亚铁链霉菌中分离到一株耐汞菌株。有趣的是，氧化亚铁链霉菌SUG2-2不仅具有依赖NADPH的汞还原酶活性，而且在细胞内也具有依赖于Fe~(2+)的汞还原酶活性，从菌株SUG_2-2中纯化的细胞色素c氧化酶在Fe~(2+)和gt；存在的情况下挥发汞，虽然使用生物修复技术既有优点也有缺点，但这项技术在清洁和保护环境方面变得更加重要。本研究描述了一种新的生物修复方法的开发，该方法使用了一种来自嗜酸、富含化学结石、铁氧化细菌的菌株氧化亚铁硫杆菌。本研究表明，耐汞氧化亚铁假单胞菌在细胞内具有独特的汞挥发系统，对酸性条件下汞污染土壤和废水的生物修复具有实际应用价值。尽管生物修复技术的使用有利有弊，但这种生态无害的自然过程在清理和保护环境方面似乎变得更加重要。

Acidithiobacillus ferrooxidans inhabits drainage in acid mines and plays a crucial role in the bacterial leaching of sulfide ores. A.ferrooxidans strains that have a high iron-oxidizing activity in the environment with many kinds of and high concentrations of heavy metals are required for microbiological leaching of low grade ores. A.ferrooxidans SUG 2-2 was isolated as a mercury-resistant strain among one hundred fifty A.ferrooxidans strains isolated from the natural environments. Interestingly, A.ferrooxidans SUG 2-2 has not only NADPH-dependent mercury reductase activity but also Fe^<2+>-dependent mercury reductase activity in the cells and cytochrome c oxidase purified from strain SUG 2-2 volatilizes mercury in the presence of Fe^<2+>Although there are both advantages and disadvantages to the use of bioremediation, this technology has become more important in cleaning up and protecting the environment. This Study describes the development of a new bioremediation method, which uses strains from an acidophilic, chemolithotrophic, iron-oxidizing bacterium Acidithiobacillus ferrooxidans. The bacterial strains decomposed and recovered metal mercury from mercury-polluted soil and wastewater.In this Study, the author shows that mercury resistant A. ferrooxidans strains have a unique mercury volatilization system in the cells and are useful for the practical use for the bioremediation of mercury polluted soil and wastewater under acidic conditions. Although there are both advantages and disadvantages to the use of bioremediation technique, this ecologically sound natural process seems to become more important in cleaning up and protecting the environment.