Abstract:
Due to the impacts of refractory organic pollutants and environment on the water treatment system, the sewage quality can not reach the standard. It is an effective measure to improve the efficiency of wastewater treatment by introducing exogenous engineering strains with relevant functional genes and the ability of horizontal gene transfer. In sewage treatment system, there are bacteria secreting signal molecules with quorum sensing. When population density reaches induction threshold, the bacteria would activate the related genes expression (such as biofilm formation, bioluminescent, antibiotics synthesis and virulence factor expression, etc.) through releasing signaling molecules, and thus trigger the behavior of other groups. Previously, researches about quorum sensing mainly concentrated on signal transduction, microbial social behavior, and medical microbiology. In recent years, stu-dies found that quorum sensing plays an important role in wastewater biological treatment and affects the colonization of the microorganism strain and pollutants degradation. Therefore, the regulation of quorum-sensing behavior is the key factor in the bioaugmentation performance. Here, we review the signaling molecules mechanism, the release of signaling molecules and its influence factors, the colonization of microbial community and the removal of pollutants. We further discussed the research from the perspective of quorum sensing biological process. The aim was to provide new idea for the effective implementation of bioaugmentation technology and the improvement of wastewater treatment efficiency, and to provide a theoretical reference for the in-depth understanding of quorum sensing regulation behavior in the process of bioaugmentation.
由于难降解有机污染物和外界环境对水处理系统的冲击干扰,污水水质常出现不达标现象。引入外源含有相关功能基因并且具有基因水平转移能力的工程菌株进行生物强化处理是提高污水处理效能的有效措施。污水处理系统中存在能够分泌信号分子的菌体,菌间具有群体感应现象,当种群密度达到感应阈值时,菌体会通过释放信号分子来触发一些群体行为,从而激活相关基因的表达(如生物膜形成、生物发光、抗生素合成和毒力因子表达等)。早期的群体感应技术研究主要集中在信号传递学、微生物社会行为学和医学微生物领域,近年来,在水处理领域也开始有相继报道,研究表明群体感应在污水生物处理中发挥重要作用,并且影响生物强化菌株的定殖和污染物降解,因此群体感应行为调控是生物强化技术成效显著与否的关键因素。本文综述了群体感应及信号分子的作用机制、信号分子释放及存在的影响因素以及群体感应对菌株定殖、微生物群落结构和污染物去除的影响,并对从群体感应角度出发研究生物强化过程进行了展望,旨在为生物强化技术的有效实施及提升污水处理效能提供一种新思路,为深入理解生物强化过程中群体感应调控行为提供理论参考。.