Self-regulatory mechanisms of anammox system in response to CuO nanoparticles revealed by microbial ecological networks and metagenomics

Area of Science:

• Environmental Microbiology
• Nanotechnology
• Biotechnology

Background:

• Anaerobic ammonia oxidation (Anammox) is a key biological nitrogen removal process.
• Copper oxide nanoparticles (CuO NPs) are widely used in industry and may affect microbial communities.
• Understanding nanomaterial impacts on Anammox systems is crucial for sustainable wastewater treatment.

Purpose of the Study:

• To investigate the effects of CuO NPs on the microbial structure and function of Anammox systems.
• To elucidate the interactions between Anammox bacteria and other microbes under CuO NP stress.
• To assess the role of microbial collaboration in maintaining Anammox system stability.

Main Methods:

• Integration of microbial network construction, metagenomics, and binning analysis.
• Addition of 1 mg/L CuO NPs to the Anammox system.
• Analysis of nitrogen removal efficiency and microbial community dynamics.

Main Results:

• Nitrogen removal efficiency initially fluctuated but stabilized after CuO NP addition.
• Significant increase in cooperative associations between Anammox bacteria and Chloroflexi (0% to 75%).
• Metagenomic analysis revealed metabolic interactions in polysaccharide, protein, and cofactor biosynthesis between AnAOB and Chloroflexi.

Conclusions:

• CuO NPs can alter microbial community structure and function in Anammox systems.
• Enhanced collaboration between Anammox bacteria and Chloroflexi is vital for system stability under CuO NP stress.
• This study highlights the importance of microbial interactions in nanomaterial-affected bioremediation processes.