Quorum sensing regulates the efficiency of a microcystin-degrading microbial consortium

Abstract

Microbial biodegradation represents an environmentally friendly solution for microcystin (MC) removal. However, the regulatory factors influencing MC biodegradation within microbial communities remain poorly understood. We hypothesized that a consortium of MC-degrading microorganisms can synergistically enhance MC biodegradation efficiency under quorum sensing (QS) signal regulation. Initially, analysis of publicly available data identified a widespread correlation between QS signals and MC-degrading genes. Subsequent laboratory studies confirmed that acyl-homoserine lactones (AHLs) represent the predominant QS signal type during the degradation of MCs by microbial consortia. A significant positive correlation was found among the AHL signal, MC degradation genes, and microbial members of the degradation process. Finally, we found that the absence of the AHL system reduced both the efficiency of MC degradation and the expression of mlr cluster genes in the microbial consortium, confirming the regulatory role of the AHL system in MC degradation at the community level. The mutualistic cooperation mechanisms were also demonstrated by metatranscriptomic and qRT-PCR analyses. These findings underscore the significant role played by the QS system in microbial community-mediated MC degradation and suggest that the manipulation of QS signals could be a promising strategy for enhancing MC treatment efficiency. Harnessing microbial cooperation through QS offers a sustainable approach for mitigating MC contamination and safeguarding water health.