Exploring multi-omics approaches in anammox-based wastewater treatment processes: A review of recent applications and...

Anaerobic ammonium oxidation (anammox) has arisen as a sustainable and energy-efficient approach for nitrogen removal in wastewater treatment. Recently, the utilization of multi-omics approaches, mainly metagenomics, metatranscriptomics, metaproteomics, and metabolomics has risen to reveal the complexity and functionality of anammox-based systems. These integrated approaches offer a comprehensive investigation of microbial community structure, gene expression, protein function, and metabolite dynamics across diverse operating contexts. Progress in high-throughput sequencing, mass spectrometry, and bioinformatics has facilitated the discovery of novel anammox bacteria, functional genes, and metabolic pathways, resulting in vital processes such as nitrogen cycling, microbial interactions, and system resilience. Metagenomics has shown the taxonomic and functional diversity within anammox consortia, whereas metatranscriptomics and metaproteomics have elucidated active metabolic pathways and functional responses to environmental alterations. Metabolomics has furnished direct evidence of metabolic states and biomarkers for enhancing reactor health and efficacy. Researchers have begun to elucidate the intricate physiological and biochemical mechanisms that govern the stability, recovery, and effectiveness of the anammox process through the integration of multi-omics datasets. This review explores recent technological breakthroughs and cutting-edge applications of multi-omics methods in anammox-based wastewater treatment. The article summarizes the principal research findings presented by numerous researchers, providing significant insights for the strategic design and management of robust and efficient water treatment systems aimed at future environmental sustainability.