UNS: Priming of Organohalide-Respirers to Degrade Chlorinated Ethenes with Natural Organochlorines

尽管经过了几十年的生物修复努力，氯化乙烯（过去广泛使用的溶剂）仍然存在，并对水系统构成重大威胁。这些化合物的生物修复取决于能够破坏这些化合物的细菌的活性，但它们的活性和存在往往很低且分布不均匀。已发表的研究表明，这些细菌在处理结构相似的天然化合物时生长。通过利用这种生理机能，可以开发出提高细菌处理这些化合物的能力的技术。本提案的目的是确定使用天然存在的有机氯化合物作为刺激剂有效修复氯化溶剂的可行性和有效性。核心假设是，有机卤化物呼吸细菌会受到刺激，对天然有机氯修正作出更快、更彻底的脱氯反应。其理由是，有了这方面的知识，氯化污染物可能会得到更彻底、更迅速的修复，从而消除对地下水系统和人类健康的主要威胁。通过研究有机卤化物呼吸细菌、天然有机氯化合物和氯化污染物之间的生物地球化学联系，可能会发现生物修复的重要障碍。目前的生物修复研究和策略集中在增加有机卤化物呼吸器的电子供体（可能还有碳）的可用性，和/或通过富含有机卤化物呼吸细菌的培养物进行生物增强。这两种方法在方法上都有一个根本的弱点，那就是假设细菌生长和能量所需的电子受体，即氯化污染物，具有足够的生物可利用性，并且生物化学上适合细菌的生物学特性。这个提议是创新的，因为它接近有机卤化物细菌的呼吸侧（电子接受侧）的刺激，其代谢使用自然产生的底物。给予有机卤化物呼吸细菌所需的电子受体以刺激其更广泛的有机卤化物呼吸能力代表了当前生物修复实践的范式转变。本提案的高通量亚转录组测序将被用作研究生水平分子方法学课程中独立研究课题的组成部分。该提案的发现也将立即纳入涵盖生物地球化学主题的本科生和研究生讲座课程，这将使本科生和研究生接触到正在进行的研究。该提案将资助一名博士生，他将前往会议展示这项工作，否则他可能不会攻读这个学位。在本科生资助下，预计最多有三名本科生研究人员将在三年的资助期内接受研究培训，这些研究人员将从事小型和独立的项目，这些项目将在当地的专题讨论会上发表。这项研究有可能从根本上影响社会。本课题旨在完成工程技术发展所需的基础知识。这项工作有可能完成未来SBIR/STTR或类似赠款所需的基本知识，然后将这项研究分阶段推向开发用于实地实施的技术。

1511767KrzmarzickDespite several decades of bioremediation efforts, chlorinated ethenes (widely used solvents in the past) are still present and pose significant threats to water systems. Bioremediation of these compounds depends on the activity of bacteria capable of destroying those compounds, but their activity and presence is often low and unevenly distributed. Published studies have demonstrated that these bacteria grow while treating naturally-occurring compounds which are similar in structure. By exploiting this physiology, technologies may be developed to enhance the ability of bacteria to treat these compounds.The objective of this proposal is to determine the feasibility and effectiveness of using naturally-occurring organochlorine compounds as stimulants for effective remediation of chlorinated solvents. The central hypothesis is that organohalide respiring bacteria will be stimulated to dechlorinate chlorinated solvents faster and more completely in response to natural organochlorine amendments. The rationale is that with this knowledge, chlorinated pollutants may be more thoroughly and quickly remediated, thus removing major threats to groundwater systems and human health. By investigating the biogeochemical links between organohalide respiring bacteria, natural organochlorine compounds, and chlorinated pollutants, a significant barrier in bioremediation is likely be found. Current research and strategies for bioremediation has focused on increasing the availability of electron donor (and perhaps carbon) to organohalide respirers, and/or by bioaugmentation with cultures rich with organohalide respiring bacteria. Both of these methods have a fundamental weakness in approach, which is the assumption that the electron acceptor needed for the bacteria's growth and energy, the chlorinated pollutant, is sufficiently bioavailable and biochemically suitable for the biology of the bacteria. This proposal is innovative because it approaches the stimulation of organohalide bacteria on the respiration side (electron-accepting side) of its metabolism using naturally produced substrates. Giving organohalide respiring bacteria the electron acceptors they need to live to stimulate their broader organohalide respiring abilities represents a paradigm shift from current bioremediation practice. The high-throughput metatranscriptomic sequencing of this proposal will be used as a component of an independent research topic undertaken in a graduate level course on molecular methodologies. Findings of this proposal will also be incorporated immediately into undergraduate and graduate lecture classes that cover biogeochemistry topics, which will expose the undergraduate and graduate students to ongoing research. The proposal will fund one PhD student who will travel to conferences to present this work and who might otherwise not pursue this degree. With undergraduate funding, up to three undergraduate researchers are expected to be trained in research over the three years of the grant, and these researchers will pursue small and independent projects which will be presented at local symposia. This research has the potential to fundamentally impact society. This proposal aims to complete the fundamental knowledge needed prior to the development of engineering technologies. This work has the potential to complete the fundamental knowledge needed for future SBIR/STTR or similar grants that would then phase this research towards the development of technologies for field implementation.