Quorum sensing signalling and activated sludge microbial communities

• Main Author: Tan, Chuan Hao
• Other Authors: Ng Wun Jern
• Format: Theses and Dissertations
• Language: English
• Published: 2014
• Subjects: DRNTU::Science::Biological sciences::Microbiology; DRNTU::Science::Biological sciences::Ecology; DRNTU::Engineering::Environmental engineering::Water treatment
• Online Access: https://hdl.handle.net/10356/61760
• Institution: Nanyang Technological University

Quorum sensing (QS) signalling has been extensively studied in the context of single- species populations. However, defining the relevance of QS in complex, multi-species microbial communities remains one of the greatest challenges for understanding the ecological role of QS in nature. Here, a long-term bioreactor ecology study was performed to address the links between QS, metabolic function, organization and composition of complex microbial consortia of the activated sludge system. The metabolic function of the community and the conversion of floccular biomass to highly structured granules were found to be non-random, but highly associated with N-acyl- homoserine-lactone mediated QS and with the engagement of multiple, phylogenetically distinct, community species. Importantly, these QS regulated behaviours were also found to be co-modulated by the biological degradation of signals, called quorum quenching. The discovery of the potential roles of QS in mixed microbial community function in this study provides an alternative to improve the operation of wastewater treatment communities.