CAREER: Microbial Degradation of Aromatic Hydrocarbons Under Anaerobic Conditions

本项目将研究厌氧细菌降解芳烃的生化和分子机制。该研究小组目前的工作已经揭示了一些新的生化反应，这些反应涉及甲苯、二甲苯和乙苯的厌氧降解的初始步骤。这些化合物的分解代谢途径将被建立和新途径的关键酶将被表征。将开始对这些途径进行遗传分析，以了解这些分解代谢基因是如何被调节的，以及哪些环境因素控制它们的表达。此外，还提出了分离在产硫和产甲烷条件下降解芳烃的新型原核生物。BTEX（苯、甲苯、乙苯、二甲苯）化合物是汽油中最易溶于水的成分之一，经常因泄漏和处理不当而释放到环境中。被污染的场地通常会变成厌氧的。从生物化学、分解代谢基因表达调控的分子机制和烃类降解生物的微生物生态学等方面研究厌氧降解BTEX，将有助于提高我们对微生物代谢的基础知识，也将对评估和加强内在生物修复具有实际意义。教学活动与科研活动相结合，具有相互关联的重点。目前正在建立环境微生物学课程，以传达对自然界微生物活动的全面了解。重点将是微生物与其环境之间的相互作用，微生物活动如何控制环境的物理化学性质，以及反过来，这如何影响微生物活动，从碳、氮、硫、氧和铁的元素循环到地球化学和人为来源的化合物的微生物代谢。

9733535 Spormann This project will investigate the biochemical and molecular mechanisms of aromatic hydrocarbon degradation by anaerobic bacteria. Current work in this research group has revealed several novel biochemical reactions involved in the initial steps of anaerobic degradation of toluene, xylenes, and ethylbenzene. Catabolic pathways for these compounds will be established and key enzymes of the novel pathways will be characterized. A genetic analysis of the pathways will be initiated to understand how these catabolic genes are regulated and which environmental factors control their expression. Further, it is proposed to isolate novel prokaryotes that degrade aromatic hydrocarbons under sulfidogenic and methanogenic conditions. BTEX (benzene, toluene, ethylbenzene, xylenes) compounds are among the most water-soluble components of gasoline and are frequently released in the environment by spills and improper handling. Contaminated sites often become anaerobic. Investigating anaerobic BTEX degradation in terms of the biochemistry involved, the molecular mechanisms that regulate expression of catabolic genes, and the microbial ecology of the hydrocarbon-degrading organisms will advance our fundamental knowledge of microbial metabolism, and will also be of practical use for evaluating and enhancing intrinsic bioremediation. The teaching activities are integrated with the research activities and have related focus. An Environmental Microbiology curriculum is currently being established to convey a comprehensive understanding of microbial activities in nature. An emphasis will be the mutual interactions between microorganisms and their environment, how microbial activities control the physical-chemical properties of an environment, and in turn, how this affects microbial activities, ranging from the elemental cycles of carbon, nitrogen, sulfur, oxygen and iron to microbial metabolism of compounds of geochemical and of anthropogenic origin.