Complete Reductive Dechlorination of Trichloroethylene (TCE) by non-Dehalococcoides Microorganisms

[摘要]伊利诺斯大学厄巴纳-香槟分校，Kevin finneran，非脱氯球菌微生物对三氯乙烯（TCE）的完全还原脱氯。1)证明了Dehalococcoides属外的生物可以完全将TCE还原为乙烯；2)利用开发的富集培养物表征了非Dehalococcoides微生物的代谢、地球化学和氯化溶剂生物降解动力学；3)验证了优势的非Dehalococcoides微生物与Desulfosporosinus属内的生物最密切相关。4)表征醋酸酯在完全脱氯过程中的氧化和利用途径，以确定它是否作为唯一的电子供体被直接氧化（通过Dehalococcoides或非Dehalococcoides液体富集培养），或确定在相同条件下它可能产生氢的机制。5)证明了在化学计量浓度下，相对于电子受体，电子给体（醋酸酯或H2）的加入，与过量电子给体的加入相比，可以更快地促进TCE还原为乙烯；6)量化了同时促进Fe（III）还原和完全脱氯的具体条件。这是第一次研究非脱氯球虫完全脱氯的可能性。这将改变基础科学和应用科学与工程，将盐呼吸作为一种代谢过程，以及氯化溶剂生物修复作为一种实践技术。此外，这项工作将描述几个鲜为人知的环境过程，包括Fe（III）还原和完全脱氯的重叠，以及醋酸盐作为盐呼吸的直接电子供体。该提案以一种所有假设都相关且独立的方式构建，所产生的数据将有利于更广泛的科学界研究基础盐呼吸科学或研究TCE应用生物修复的人。拟议的推广计划既包括环境工程中代表性不足的群体的学生，也包括最终将从数据中受益的从业者。这些学生将包括研究生和本科生，并将专门从少数民族和女学生项目中招收。实践者方面最终将与已经表示对工作感兴趣的一个团体直接接触，并通过会议和向其区域办事处的小团体进行个人介绍与其他团体直接接触。整个研究人员，包括拟议的博士后学者，将与所有实践者互动，使他们习惯于从实验室到实地的研究过渡，以及环境工程实践的务实方面如何影响基础研究科学。

ABSTRACTCBET-0853835Finneran, Kevin TUniversity of Illinois at Urbana-ChampaignComplete Reductive Dechlorination of Trichloroethylene (TCE) by non-Dehalococcoides MicroorganismsThe objectives of the proposed work are to: 1) demonstrate that organisms outside of the genus Dehalococcoides can completely reduce TCE to ethene, 2) use the enrichment cultures developed to characterize the metabolism, geochemistry, and chlorinated solvent biodegradation kinetics of non-Dehalococcoides microorganisms, 3) verify that the dominant non-Dehalococcoides microorganism(s) are most closely related to organisms within the genus Desulfosporosinus, 4) characterize the pathway for acetate oxidation and utilization during complete dechlorination to determine if it is directly oxidized as the sole electron donor (by Dehalococcoides or non-Dehalococcoides liquid enrichment cultures) or to define the mechanisms by which it may generate hydrogen under the same conditions, 5) demonstrate that electron donors (acetate or H2) added at stoichiometric concentrations relative to the electron acceptors present promotes faster TCE reduction to ethene when compared to excess electron donor addition, and 6) quantify the specific conditions in which Fe(III) reduction and complete dechlorination are promoted simultaneously.This is the first research to address the probability of non-Dehalococcoides complete dechlorination. This will change fundamental and applied science and engineering with respect to halorespiration as a metabolic process, and chlorinated solvent bioremediation as a practiced technology. In addition, the work will characterize several poorly understood environmental processes including the overlap of Fe(III) reduction and complete dechlorination, and acetate as a direct electron donor for halorespiration. The proposal has been constructed in a manner that all hypotheses are relevant and independent, and the data generated will benefit the broader scientific community studying basic halorespiration science or those investigating applied bioremediation of TCE.The proposed outreach plan incorporates both students who are members of underrepresented groups in environmental engineering, and practitioners who will ultimately benefit from the data. The students will be both graduate level and undergraduate level, and will be recruited specially from programs for minority and female students. The practitioner aspect will culminate in direct contact with one group who has already expressed interest in the work and with others via conferences and individual presentations to small groups at their regional offices. Entire research staff including the proposed postdoctoral scholar will interact with all practitioners such that they become accustom to the lab to field transition for research, and how the pragmatic aspects of environmental engineering practice can influence fundamental research science.