MICROORGANISMS THAT DEGRADE AROMATIC XENOBIOTIC POLLUTANTS

以前的工作已经描绘了一些重要的物理和生物 影响生物降解过程的特征 污染场地的生物回收。 微生物已经被分离出来 来自碳过滤器和污染物羽流， 苯，甲苯， 甲苯和二甲苯（BTEX）降解。 此外，相关研究 氯代芳香族化合物的厌氧降解表明， 广泛的底物特异性与还原性相关的机制 脱氯 本建议纳入了在 制定具体目标，以进一步 研究微生物的相互作用伴随着生物回收，并扩大了 本工作的范围为多环芳烃和氯化芳香化合物的研究 退化也是。 项目0010、0011、0012和0013的主要目标是评估 微生物在种群中的相互作用， 模拟自然环境中与生物降解相关的种群 环境;探索播种BTEX污染土壤的效用， 在GAC上建立的种群;并描述 厌氧细菌的亚细胞成分脱氯。 特别 注意力将集中在氧含量的影响和 交替电子受体对降解过程影响 缺氧环境 在某些项目中，将采用重组DNA技术进行克隆 将降解微生物的元素转化为异质细菌， 进一步阐明与这些调节相关的机制， 途径。 源自“基准”的多变量分子探针 微生物将被用来估计种群动态发生 在适应生物降解过程中。 这些探测器将 进一步用于研究模拟含水层环境中的种群。 此外，还将通过以下方式评估还原脱氯的机制： 研究天然金属有机物对 氯代有机化合物的降解。 这些信息 研究将用于优化原位生物回收 技术.

Previous work has delineated some important physical and biological features which affect biodegradation processes associated with the bioreclamation of contaminated sites. Microorganisms have been isolated from both carbon filters and contaminant plumes which exhibit diversity in species and the metabolic pathway(s) used for benzene, toluene, ethylbenzene and xylene (BTEX) degradation. In addition, studies related to the anaerobic degradation of chloroaromatic compounds suggest potential broad substrate specificity for the mechanisms associated with reductive dechlorination. This proposal incorporates knowledge gained in the previous project period towards the formulation of specific aims to further study microbial interactions attendant to bioreclamation and extends the purview of this work to studies of PAH and chlorinated aromatic compound(s) degradation as well. The major goals of Projects 0010, 0011, 0012 and 0013 are to evaluate microbial interactions in populations which contribute to the ascendancy of populations associated with biodegradation in simulated natural environments; to explore the utility of seeding BTEX contaminated soil with populations established on GAC; and to describe mechanisms for dechlorination by subcellular components of anaerobic bacteria. Particular attention will be focused on the influence of oxygen content and the influence of alternate electron acceptors on degradative processes in anoxic environments. For some projects, recombinant DNA technology will be employed to clone elements of degradative microorganisms into heterogenetic bacteria to further elucidate mechanisms associated with the regulation of these pathways. Multivariant molecular probes derived from "benchmark" microorganisms will be used to estimate population dynamics occurring during adaptation to a biodegradation process. These probes will be further utilized to study populations in simulated aquifer environments. In addition, mechanisms for reductive dechlorination will be assessed by examining the influence of natural metal-organics on the rates and extent of degradation on chlorinated organic compounds. Information from these studies will be utilized towards the optimization of in situ bioreclamation technology.