RAPID: Assessing the impact of chemical dispersents on the microbial biodegradation of oil immediately following a massive spill

深水地平线事件中大量的石油泄漏导致了前所未有的分散剂的使用，其中包括用于溶解石油和防止浮油形成的表面活性剂化合物的混合物。先前的研究表明，表面活性剂对生物降解的影响是复杂的，而它们对微生物群落降解原油中发现的许多碳氢化合物的能力的影响却知之甚少。碳氢化合物降解细菌对底物的偏好不同，对表面活性剂的反应也不同，这对生物降解的速度和程度起着重要作用。在快速反应研究基金（rapid）的资助下，加州大学圣巴巴拉分校的研究人员将使用化学和生物工具相结合的方法来跟踪石油成分的变化、微生物群落的变化和表面活性剂的数量，以确定这些分散剂对生物降解的影响。油的定量和成分将采用气相色谱法测定，包括全面采用二维气相色谱法。通过分析16S rRNA基因和碳氢化合物氧化功能基因来确定微生物群落的变化，并通过实时荧光定量PCR对特定的群落成员进行定量。表面活性剂将用LC-MS或其他技术进行鉴定和定量。最初的采样将以海岸为基础，在条件允许的情况下，计划进行深水和沉积物采样。在这次泄漏的早期阶段取样的机会将提供重要的基线信息，并使对墨西哥湾石油和分散剂的命运进行长期研究成为可能。这项提案的广泛影响包括一名本科生研究员和一名博士后研究员的参与，以及与大众新闻媒体的合作，以教育公众有关分散剂的影响和这次泄漏的石油的命运。

The massive release of oil from the Deepwater Horizon incident has led to an unprecedented use of oil dispersants, which include a mix of surfactant compounds designed to dissolve oil and prevent slick formation. Previous research has shown mixed effects of surfactants on biodegradation and little is known about their effects on the ability of microbial communities to degrade the many hydrocarbon compounds found in crude oil. Hydrocarbon degrading bacteria differ in their substrate preferences, as well as in their response to surfactants, which will play an important role in determining the rate and extent of biodegradation. With funding from this Grant for rapid Response Research (RAPID), researchers at the University of California at Santa Barbara will use a combination of chemical and biological tools to track changes in the composition of the oil, changes in the microbial community, and the amount of surfactant present, in order to determine the impact of these dispersants on biodegradation. Oil quantification and composition will be determined by gas chromatography, including the use of comprehensive two-dimensional gas chromatography. Microbial community changes will be determined by analysis of the 16S rRNA gene and functional genes for hydrocarbon oxidation, and specific members of the community will be quantified with quantitative real time PCR. Surfactants will be identified and quantified with LC-MS or other techniques. Initial sampling will be shore based, with deep water and sediment sampling planned as conditions allow. The opportunity to sample in the early stages of response to this spill will provide important baseline information and enable longer term studies on the fate of oil and dispersants in the Gulf of Mexico. Broader impacts of this proposal include the involvement of an undergraduate researcher and a postdoctoral researcher, as well as collaboration with the popular news media to educate members of the public on the effects of dispersants and the fate of oil from this spill.