胞外DNA在生物膜构建中的作用研究进展

生物膜是指细菌为适应外界环境的变化而形成的特殊微生物聚合体，生物膜法是水的生化处理技术的重要分支，在环境工程领域具有重要的位置。本文综述了胞外DNA (extracellular DNA, eDNA)在生物膜形成过程中的作用，首先介绍胞外聚合物(extracellular polymeric substance, EPS)分类以及eDNA在EPS中的分布情况；其次阐述群体感应(quorum sensing, QS)系统调节eDNA在细菌中的释放；为说明eDNA在生物膜形成过程中的机理，本文采用了XDLVO理论揭示eDNA调节细菌的粘附和聚集性能，并探讨了eDNA与蛋白质(proteins, PN)及多聚糖(polysaccharides, PS)的结合行为；最后，对该领域未来的研究方向进行了展望。

Research progress of the role of extracellular DNA in the biofilm construction

Biofilm is refers to the bacteria forming the special microbial aggregations in order to adapt to the change of external environment. The biofilm process is an important branch of water biochemical treatment technology, which is becoming more and more attentive in the field of environmental engineering. The article summarized studies on the role of extracellular DNA in the process of biofilm forming. Firstly, the classification of extracellular polymeric substance and eDNA distribution in EPS were described. Further, it illuminated that QS-mechanism mediated the release of eDNA in the bacterial cells. In order to provide more detailed information about the role of eDNA in the process of biofilm forming, the eDNA-mediated performance in the adhesion and aggregation of bacterial was revealed according to XDLVO theory. Moreover, the combinative behavior of eDNA with PN and PS were also discussed, respectively. Lastly, the future trends in the influence of eDNA on the process of biofilm forming in the coming years were addressed.