Mailloux Brian J, Alexandrova Ekaterina, Keimowitz Alison R, Wovkulich Karen, Freyer Greg A, Herron Michael, Stolz John F, Kenna Timothy C, Pichler Thomas, Polizzotto Matthew L, Dong Hailiang, Bishop Michael, Knappett Peter S K
Environmental Science Department, Barnard College, New York, New York 10027, USA.
Appl Environ Microbiol. 2009 Apr;75(8):2558-65. doi: 10.1128/AEM.02440-07. Epub 2009 Feb 27.
Tens of millions of people in Southeast Asia drink groundwater contaminated with naturally occurring arsenic. How arsenic is released from the sediment into the water remains poorly understood. Here, we show in laboratory experiments that phosphate-limited cells of Burkholderia fungorum mobilize ancillary arsenic from apatite. We hypothesize that arsenic mobilization is a by-product of mineral weathering for nutrient acquisition. The released arsenic does not undergo a redox transformation but appears to be solubilized from the apatite mineral lattice during weathering. Analysis of apatite from the source area in the Himalayan basin indicates the presence of elevated levels of arsenic, with an average concentration of 210 mg/kg. The rate of arsenic release is independent of the initial dissolved arsenic concentration and occurs at phosphate levels observed in Bangladesh aquifers. We also demonstrate the presence of the microbial phenotype that releases arsenic from apatite in Bangladesh aquifer sediments and groundwater. These results suggest that microbial mineral weathering for nutrient acquisition could be an important mechanism for arsenic mobilization.
东南亚数千万人饮用着被天然存在的砷污染的地下水。砷是如何从沉积物中释放到水中的，目前仍知之甚少。在这里，我们通过实验室实验表明，伯克霍尔德氏菌在磷酸盐限制的情况下能从磷灰石中 mobilize 辅助性砷。我们推测，砷的 mobilization 是矿物风化获取养分的副产品。释放出的砷没有经历氧化还原转变，而是在风化过程中似乎从磷灰石矿物晶格中溶解出来。对喜马拉雅盆地源区磷灰石的分析表明存在高含量的砷，平均浓度为210毫克/千克。砷的释放速率与初始溶解砷浓度无关，且在孟加拉含水层中观察到的磷酸盐水平下发生。我们还证明了在孟加拉含水层沉积物和地下水中存在从磷灰石中释放砷的微生物表型。这些结果表明，微生物为获取养分而进行的矿物风化可能是砷 mobilization 的一个重要机制。
“mobilize”在文中多次出现，暂未找到完全合适的中文对应词，这里保留英文，你可根据上下文准确理解其含义。
