Activated sludge microbial communities influencing the performance of a full-scale wastewater treatment plant treating optoelectronic wastewater

Microbial communities of activated sludge play vital roles in the biological treatment of wastewater. Next-generation sequencing (NGS) has assisted in increasing our knowledge of the activated sludge microbial communities treating various municipal and industrial wastewaters. However, our understanding of microbial communities in optoelectronic wastewater treatment systems remains limited. This study explored the microbial community dynamics of a full-scale activated sludge process that treated optoelectmnic wastewater. Samples collected during periods of different system performance were sequenced via NGS of 16 S rRNA amplicons using the Illumina HiSeq platform. Indicator taxa analyses revealed that bacterial genera (e.g., Thauera) resisted the extreme ionizing radiation, and those capable of degrading aromatic compounds (e.g., Acinetobacter) were substantially lower in diversity and abundance during the low-performance period as compared to the high-performance period. In addition, the low-performance group lacked bacterial genera that are important in the nitrification process (e.g., Nitrospira). Moreover, co-occurrence network analyses indicated that the average path length and network diameter of microbial taxa were substantially shorter during the high-performance period, indicating efficient information dissemination among taxa. Collectively, these findings may aid in the design and/or optimization of systems with improved performance in treating optoelectronic industrial wastewater.