油页岩干酪根降解细胞工程菌的构建

Faced with the increasing crisis of energy resources shortage and environmental pollution, it has become an urgent job to reasonably develop and utilize alternative energy resources. Oil shale is one of the significant alternative energy resources in the 21st century because of its enormous reserves, favorable characteristics and convenient development and utilization. Microbial degradation technology provides a new way different from conventional physical and chemical methods for the development and utilization of oil shale, which has the advantages of low cost, in-situ degradation and no pollution products. This approach has been well used in the biodegradation of inorganic minerals in oil shale. However, the biodegradation of kerogen in oil shale is still in its infancy, and it is a key to seeking the efficient kerogen-degrading bacteria. This study is to carry out the following procedures to obtain high efficient kerogen-degrading bacteria. Firstly, indigenous kerogen-degrading bacteria isolated from oil shale mine are screened and identified. Secondly, the indigenous kerogen-degrading bacteria are processed by mutation breeding to screen out mutant strain with better biodegradation efficiency. Thirdly, the protoplasts of the mutant strain are fused with the protoplasts of white rot fungi suitable for the biodegradation of macromolecular organic compounds and Rhodococcus erythropolis producing biosurfactants, in order to construct high efficient kerogen-degrading cell engineering bacteria. Lastly, the biodegradation characteristics of kerogen are investigated and then the biodegradation mechanism of kerogen is discussed. This new attempt is helpful to overcome the obstacles in the biodegradation of kerogen, which have important significance for clean and high efficient utility of oil shale.

面对日益加剧的能源和环境危机，合理开发利用接替能源成为当务之急。油页岩以丰富的资源、有利的特性和开发利用的可行性而被列为21世纪重要的接替能源。微生物降解技术提供了一条有别于常规物理和化学法开发利用油页岩的新途径，具有成本低廉、原位性和无二次污染等优越性，并已在油页岩中无机矿物质的微生物降解中得到良好应用。可是，油页岩中有机质干酪根的微生物降解研究尚处于起步阶段，寻求干酪根高效降解菌是影响其发展的关键。本项目拟从油页岩矿中分离筛选出内源干酪根降解菌，用微生物诱变育种技术筛选出更高降解效率的诱变菌株，再用原生质体融合技术将此诱变菌株与适于大分子有机物降解的白腐真菌和产生物表面活性剂的红平红球菌三者进行原生质体融合，以期构建干酪根高效降解细胞工程菌，力图了解干酪根微生物降解特性，探讨干酪根微生物降解机理。这一新尝试有助于打破干酪根生物降解的瓶颈，对油页岩的清洁高效利用具有重要意义。

油页岩中有机质干酪根的成分和结构非常复杂，是生成石油和天然气的原始物质。利用微生物降解干酪根因其绿色环保、能耗低及原位性等优点越来越受到重视，其中寻求干酪根高效降解菌是影响其发展的关键。我们针对这一问题进行了多方面的尝试，取得了一些研究成果。我们从油页岩矿中分离并鉴定了内源干酪根降解菌，用紫外诱变技术获得了更高降解能力的诱变菌株；拓展研究了中国主要油页岩矿中细菌和真菌多样性，揭示了各矿中微生物群落的组成结构、优势微生物类群、相对数量和空间分布等信息；构建并筛选出以球红假单胞菌和解脂亚罗酵母为亲本菌株的2株细胞工程菌，用于干酪根、地沟油和柴油的生物降解中；研究了白腐真菌对硝化处理后油页岩的降解作用，考察了培养基、诱导剂、pH值和温度等因素对白腐真菌降解油页岩的影响，分析了其降解产物的特性；用紫外诱变技术处理了白腐真菌，筛选出2株高产酶活性的正突变株，用于后续干酪根降解。在本项目执行期间，我们培养了1名博士和6名硕士，完成博士论文1本，硕士论文3本；在国内外期刊上发表了论文8篇，其中2篇SCI收录，5篇EI收录；参加国内外学术会议3次，发表国际会议论文3篇。