芘是常见的多环芳烃类环境污染物。邻苯二酚是芳香族化合物降解的重要中间产物。邻苯二酚2，3-双加氧酶（B2C23O）催化的开环反应是芳香族化合物降解的限速步骤。为了显著提高芘降解菌Pseudomonas sp. B2的降解能力，获得生态适应性强的新型重组菌，本项目拟基于芘降解途径中最关键的B2C23O基因，以本源菌株B2为宿主，通过同源重组的方法，将受芳香族化合物诱导的Pdmp启动子: :T7 RNA聚合酶基因单元和高效启动子PT7:: B2C23O基因单元整合进该菌株的基因组中，实现B2C23O基因受芳香族化合物诱导的高效表达，加快芘降解途径的代谢流；基于该基因的序列的新颖性和特异性，通过精确的实时定量PCR(real-time PCR)对该菌株在不同时间（年份和季节）、不同空间（土壤环境和土层）的变化规律进行研究，为高效芳香族化合物重组菌的构建及环境释放提供新的思路和科学的依据。

Pyrene is a common polycyclic-aromatic-hydrocarbons-type environmental contaminants. Catechol is an important intermediate product in the degradation pathway of aromatic compound. Catechol 2,3-dioxygenase (B2C23O) catalyzed ring-opening reaction is the rate-limiting step in the degradation of aromatic compounds. In order to significantly improve the degrading capacity of pyrene-degradation bacterium Pseudomonas sp. B2, and acquire a new recombinant strain with strong ecological adaptability, This project is intended to construct the recombinant strain based on the most important gene, B2C23O, in pyrene degradation pathway, and use the origin strain B2 as the host. By a homologous recombination method, the gene units, aromatic-compound-induced Pdmp promoter :: T7 RNA polymerase, and high-efficient promoter PT7 :: B2C23O, were integrated into the genome of the strain B2, to achieve the efficient expression of the B2C23O genes induced by aromatic compounds, and accelerate the metabolism flow of the pyrene degradation pathways. Moreover, based on the novelty and specificity of the B2C23O gene sequence, the variation of the recombinant strain in different years and in different seasons (temporal), in different soil environment and soil layers (spacial) were studied through accurate real-time quantitative PCR (real-time PCR). The conduction of this project could provide new ideas to construct a high efficient aromatic compounds degradation recombinant bacteria, and present scientific support for their environmental release.