Biogeochemical Controls over Corrinoid Bioavailability to Organohalide-Respiring

描述(申请人提供)：暴露在有毒化学物质污染的水中威胁人类健康。根除美国约12.6万个危险废物场所将需要超过1000亿美元。这一努力结合了净化、环境恢复和迅速保护人类健康迫切需要的创新和经济高效的技术。四氯乙烯(PCE)和三氯乙烯(TCE)等氯化溶剂及其转化产物二氯乙烯(DCES)和氯乙烯(VC)是主要的风险驱动因素，与免疫系统受损、癌症、肾和肝脏损害以及帕金森氏症有关。对还原脱氯为无毒乙烯所涉及的微生物学的科学了解促进了氯化乙烯场所的清理工作。尽管前景看好，但当DCE和VC还原脱氯效率低下导致DCE/VC停滞时，往往无法实现解毒和现场关闭。麦卡氏脱卤球菌属(DHC)菌株是参与DCES和Vc还原脱氯为环境友好型乙烯的关键细菌。DHC生态生理学和营养要求的知识有望提高DCE和VC的脱氯率，克服DCE/VC停滞，并导致更有效的生物修复，以减少人类与这些危险化学品的接触。结合基于培养的方法、高通量测序、生物信息学分析和最先进的分析程序的详细研究将揭示DHC还原脱氯活性受到/不受足够皮质激素辅因子供应限制的生物地球化学条件。一种创新的、 高通量定量聚合酶链式反应工具(即B12-q芯片)将被设计、验证并提供给社区，以识别皮质激素的生物利用度何时限制了DHC还原脱氯活性。新工具和知识的应用将改善污染场地的管理，使特定的场地处理能够实现有效的解毒，有效保护人类暴露在有毒和致癌化学品中，减少补救时间和成本，同时减轻生物修复处理的负面次要环境影响(例如，温室气体排放减少，稳定的PH值避免有毒金属释放)。

DESCRIPTION (provided by applicant): Exposure to water tainted with toxic chemicals threatens human health. In excess of $100 billion will be required to eradicate the ~126,000 hazardous waste sites in the U.S. This effort incorporates innovative and cost-efficient technologies that are urgently needed for decontamination, environmental restoration and prompt protection of human health. Chlorinated solvents like tetrachloroethene (PCE) and trichloroethene (TCE), and their transformation products, dichloroethenes (DCEs) and vinyl chloride (VC), are major risk drivers and are linked to compromised immune systems, carcinogenesis, kidney and liver damage, and Parkinson's disease. Scientific understanding of the microbiology involved in reductive dechlorination to non-toxic ethene has invigorated cleanup efforts at chlorinated ethene sites. Although promising, detoxification and site closures are often not achieved when inefficient DCE and VC reductive dechlorination leads to DCE/VC stalls. Dehalococcoides mccartyi (Dhc) strains are keystone bacteria involved in the reductive dechlorination of DCEs and VC to environmentally benign ethene. Knowledge of Dhc ecophysiology and nutritional requirements promises to increase DCE and VC dechlorination rates, overcome DCE/VC stalls, and lead to more efficient bioremediation to reduce human contact with these dangerous chemicals. Detailed studies combining cultivation-based approaches, high-throughput sequencing, bioinformatics analyses, and state-of-the art analytical procedures will reveal the biogeochemical conditions, under which Dhc reductive dechloirnation activity is/is not constrained by adequate corrinoid cofactor supply. An innovative, high-throughput quantitative PCR tool (i.e., the B12-qChip) will be designed, validated and made available to the community to recognize when corrinoid bioavailability limits Dhc reductive dechlorination activity. Application of the new tool and knowledge will improve contaminated site management by enabling site specific treatment to achieve efficient detoxification, effectively protect human exposure to toxic and carcinogenic chemicals, reduce remediation times and costs, while mitigating negative secondary environmental impacts of bioremediation treatment (e.g., lower greenhouse gas emissions, stable pH avoids toxic metal release).