Microbial Community Structure of Mesophilic and Low-temperature Partial Nitrification-anammox Reactors: Distribution and Functional Roles of the Core Microbiome

Abstract

Microbial community structures in mesophilic and low-temperature anammox and partial nitrification–anammox reactors were exami­ned by a 16S rRNA–gene amplicon sequencing ana­lysis. The anammox bacterium, Jettenia sp., was dominant, and nitrifying bacteria, including Nitrosomonas sp. (aerobic ammonia–oxidizing bacterium) and Nitrospira sp., (nitrite–oxidizing bacterium) coexisted in the bioreactors. Core coexisting bacteria, such as Sulfurisoma sp. and Zeimonas sp., showed oxygen-scavenging and NO₃^– reduction potentials. Sulfurisoma-related bacteria are distributed across wastewater treatment plants worldwide, particularly in denitrification systems. These results underscore the ecological and functional importance of microbial consortia in enhancing nitrogen removal efficiency.