ADVANCE Fellows Award: Molecular Ecology Techniques Based on Ribosomal RNA Detection of Microbial Population

0137368 Sierra该研究的目的是在高速率硫酸盐还原生物反应器中开发一种生物矿化过程，适用于从含水废物或工艺流中去除和回收重金属。硫酸盐还原菌产生的生物硫化物将促进金属的固定化。选择铜（Cu）作为模型金属，因为这种污染物以高浓度存在于许多工业废水（例如，该项目将从连续厌氧生物反应器开始，以确定在嗜温和嗜热系统中生产硫化物的最合适的电子供体。实验还将评估控制从合成废水中去除铜的主要因素。基于rRNA检测、电子显微镜和X射线光谱的分子方法将用于评估微生物种群的结构和功能，并确定厌氧生物膜系统中矿物质的形态和分布。 所获得的知识将被应用于阐明的基本机制，并确定负责在硫化物生物反应器中去除铜的关键微生物。 此外，将开发一个化学平衡模型来模拟生物反应器中的铜分配和去除，以促进工艺优化。在该项目的最后部分，处理半导体制造中产生的铜污染流（即，将研究化学机械平坦化（CMP））以确定在实际条件下Cu去除的效率。 选择CMP废水是因为其对东道国机构的重要性，并加强与NSF/SCR中心的合作。 预计这项研究将导致提高科学和技术的理解的潜力，硫酸盐还原生物过程的金属去污。

0137368 Sierra The objective of the research is to develop a biomineralization process in high-rate sulfate reducing bioreactors applicable to the removal and recovery of heavy metals from aqueous waste or process streams. Metal immobilization will be stimulated by biogenic sulfides produced by sulfate reducing bacteria. Copper (Cu) was chosen as model metal, since this contaminant is present at high concentrations in many industrial effluents (e.g., mining, semiconductor, metallurgical and metal-finishing industries) and is a particularly toxic priority pollutant.The project will be initiated with continuous anaerobic bioreactors to determine the most suitable electron donor for sulfide production in mesophilic and thermophilic systems. The experiments will also assess the main factors controlling Cu removal from synthetic effluents. Molecular methods based on rRNA detection, electron microscopy and X-ray spectroscopy, will be used to evaluate the structure and function of the microbial population and to determine the speciation and distribution of the minerals in the anaerobic biofilm system. The knowledge gained will be applied to elucidate the underlying mechanisms-and identify the key microorganisms responsible for Cu removal in sulfidogenic bioreactors. In addition, a chemical equilibrium model will be developed to simulate Cu partitioning and removal in the bioreactors in order to facilitate process optimization. In the final part of the project, the treatment of a Cu-contaminated stream generated in semiconductor manufacturing (i.e., chemical mechanical planarization (CMP)) will be investigated to determine the efficiencies of Cu removal under practical conditions. CMP effluents were selected because of their significance to the host institution's State and to enhance collaboration with the NSF/SCR Center. It is anticipated that this research will lead to improved scientific and technological understanding of the potentials of sulfate reducing bioprocesses for metal decontamination.