Engineering a Pseudomonas putida as living quorum quencher for biofilm formation inhibition, benzenes degradation, and environmental risk evaluation

• Published in: Water research (Oxford) 2023-11, Vol.246, p.120690-120690, Article 120690
• Main Authors: Xue, Yi-Mei, Wang, Yong-Chao, Lin, Yu-Ting, Jiang, Guan-Yu, Chen, Rui, Qin, Ruo-Lin, Jia, Xiao-Qiang, Wang, Can
• Format: Article
• Language: English
• Subjects: Biofilm formation inhibition; Engineering bacteria; Environmental risk; Quorum quenching; Signal molecules
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2023.120690

•An engineered QQ bacteria was successfully constructed using Pseudomonas putida.•The engineered bacteria achieved both biofilm formation control and benzene series degradation.•The environmental risk of this engineered bacteria was controllable in actual activated sludge. Bacterial communication interruption based on quorum quenching (QQ) has been proven its potential in biofilm formation inhibition and biofouling control. However, it would be more satisfying if QQ could be combined with the efficient degradation of contaminants in environmental engineering. In this study, we engineered a biofilm of Pseudomonas putida through introducing a QQ synthetic gene, which achieved both biofilm formation inhibition and efficient degradation of benzene series in wastewater. The aiiO gene introduced into the P. putida by heat shock method was highly expressed to produce QQ enzyme to degrade AHL-based signal molecules. The addition of this engineered P. putida reduced the AHLs concentration, quorum sensing gene expression, and connections of the microbial community network in activated sludge and therefore inhibited the biofilm formation. Meanwhile, the sodium benzoate degradation assay indicated an enhanced benzene series removal ability of the engineering bacteria on activated sludge. Besides, we also demonstrated a controllable environmental risk of this engineered bacteria through monitoring its abundance and horizontal gene transfer test. Overall, the results of this study suggest an alternative strategy to solve multiple environmental problems through genetic engineering means and provide support for the application of engineered bacteria in environmental biotechnology. [Display omitted]