基于纯培养及组学方法研究环境中雌激素降解菌的作用机制

Natural and synthetic estrogens in the environement can cause endocrine disruption in the male animals and therefore, have received increasing attention. Microbial degradation of estrogens is considered as the major way for their removal in the constructed and natural environments. However, currently limited genetic information about these estrogen-degrading bacteria is available. We have completed the first whole genome sequencing of an estroen-degrading bacterium. We also have isolated estrogen-degrading bacteria from Xiamen belonging to five different genera. Based on our previous efforts of estrogen biodegradation, I proposed the following research plans. First, according to the whole genome sequencing, we have identified a possible gene cluster which might be related to the ring cleavage of estrogens. We plan to further clone the genes in the cluster and confirm the function of these genes. Second, with the help of whole genome sequencing, we plan to use proteomic and transcriptomic approaches and metabolites analysis using high resoultion mass spectrometry to reveal the netwok of genes involved in estrogen metabolism. Third, we plan to sequence the genomes of the isloated estrogen-degrading bacteria and use the comparative genomic approach to explore the difference of structure and evolution of estrogen-degrading genes among different estrogen-degrading bacteria. The results of this research will improve our understanding of the diversity and function of estrogen-degrading bacteria in the environment.

环境中的天然及合成的雌激素引发的动物雌性化问题已经引起了社会的广泛关注。微生物降解作用被认为是去除环境中雌激素的最主要途径，然而目前仍缺乏对雌激素降解菌做基因方面的深入研究。申请人研究组已完成首株雌激素降解菌全基因组测序工作，并已于厦门地区分离到5个不同属的雌激素降解菌。本项目拟在前期基础上开展以下的研究：1.根据雌激素降解菌测序后的基因比对分析结果，初步找到了与雌激素开环相关的基因，本项目拟进一步进行克隆表达分析，并确定基因功能。2.在全基因组测序的基础上，拟应用蛋白质组学、转录组学及代谢产物分析方式研究雌激素降解菌降解雌激素的完整代谢通路。3.拟对分离的5个不同属的雌激素降解菌进行全基因组测序并开展比较基因组的研究工作，以探讨不同雌激素降解菌的雌激素降解代谢途径、基因结构及进化历史之间的异同。以上研究结果有助于为环境中雌激素降解菌的多样性研究提供新的科学依据。

环境中的天然及合成的雌激素引发的动物雌性化问题已经引起了社会的广泛关注。微生物降解作用被认为是去除环境中雌激素的最主要途径，然而目前仍缺乏对雌激素降解菌做基因方面的深入研究。申请人研究组已完成首株雌激素降解菌全基因组测序工作，本项目在前期基础上深入挖掘了雌激素降解菌中关键的开环基因簇,并开展以下的研究： 1.鉴定了三株雌激素降解菌新种并对其降解特性进行了初步研究；2.根据雌激素降解菌KC8测序后的基因比对分析结果，初步找到了与雌激素开环相关的基因，进一步通过蛋白质组及转录组进行解析并通过克隆表达分析验证基因功能，在此基础上，采用高效液相色谱质谱手段分离纯化得到了中间代谢产物。3.以本项目中发现的中间代谢产物为标记，探究自然水体中雌激素的微生物代谢途径，证实该途径在自然水体中广泛存在并受限于环境中NH4+的浓度。4.选取四株雌激素高效降解菌进行固定化应用研究及结合膜生物反应器证实这些菌株在污水处理中对于去除雌激素具有潜在的应用价值。以上研究结果有助于为环境中雌激素降解菌的多样性研究及其应用前景提供新的科学依据。