Research Information System
Biodegradation, vol.36, no.3, 2025 (SCI-Expanded)
Anammox has emerged as a cost-effective and eco-friendly biological treatment technology for high-strength wastewater, and hydrazine (N2H4) is a unique intermediate in the anammox metabolism. This study presents the first investigation into the genetic responses of anammox bacteria to elevated N2H4 concentrations, offering critical insights into their potential for sustainable environmental applications. In this scope, anammox cultures were exposed to high levels of N2H4 (up to 3 g/L) over a short-term period to evaluate their nitrogen treatment capacity and transcriptional responses. The results indicated that anammox activity continued at N2H4 concentrations of 1.88 g/L or less. However, acute N2H4 exposure significantly downregulated key genes, such as acetyl-CoA synthase beta and delta subunits, hydrazine synthase, hydrazine dehydrogenase, and hydroxylamine oxidoreductase, except for AAA family ATPase. Overall, high exogenous N2H4 concentrations severely constrained the metabolism and survival of anammox bacteria at a molecular level. Understanding the genetic responses of anammox bacteria to elevated N2H4 concentrations is crucial for optimizing their application in further anammox-based technologies. Future studies should focus on improving the resilience of anammox bacteria to high N2H4 concentrations, thereby broadening their applicability in engineered wastewater treatment and biotechnological processes while maintaining system stability and efficiency.