Successional dynamics and alternative stable states in a saline activated sludge microbial community over 9 years

• DOI: 10.1186/s40168-021-01151-5
• Publication Date: 2021-10-07T08:40:39Z
• Authors: Yulin Wang; Jun Ye; Feng Ju; Lei Liu; Joel A. Boyd; Yu Deng; Donovan H. Parks; Xiaotao Jiang; Xiaole Yin; Ben J. Woodcroft; Gene W. Tyson; Philip Hugenholtz; Martin F. Polz; Tong Zhang
• Keywords: Community; Alternative stable state

Abstract Background Microbial communities in both natural and applied settings reliably carry out myriads of functions, yet how stable these taxonomically diverse assemblages can be what causes them to transition between states remains poorly understood. We studied monthly activated sludge (AS) samples collected over 9 years from a full-scale wastewater treatment plant answer complex AS evolve the long term community functions change when there is disturbance operational parameters. Results Here, we show that microbial system fluctuated around average for 3 but was then abruptly pushed into an alternative state by simple transient (bleaching). While taxonomic composition rapidly turned new following disturbance, metabolic profile performance remained remarkably stable. A total 920 metagenome-assembled genomes (MAGs), representing approximately 70% ecosystem, were recovered 97 metagenomes. Comparative genomic analysis revealed increased ability aggregate cohorts MAGs with correlated dynamics are dominant after bleaching event. Fine-scale also dominated during different periods showed successional on seasonal longer time scales due temperature fluctuation gradual changes mean residence reactor, respectively. Conclusions Our work highlights assume under highly similar environmental conditions specific threshold may lead rapid shift composition.