Stable nitrogen removal by anammox process after rapid temperature drops: Insights from metagenomics and
Sike Wang1, Kento Ishii2, Heng Yu3
1Shenzhen International Graduate School, Tsinghua University, Shenzhen, China; State Key Joint Laboratory of Environmental Stimulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
Abstract:
This study investigated the impacts of rapid temperature drops on anammox process performance and the metabolism of its core microbial populations through proteomic analysis. Over a 50-day period, the temperature of an up-flow granular bed anammox reactor was stepwise decreased from 35 °C to 15 °C and resulted in repeated transient increases in effluent nitrite concentrations. At 15 °C, a nitrogen removal rate of 2.71 ± 0.23 gN/(L·d) was maintained over 100 days operation. Total AnAOB population abundance (20.9%±4.9%) and AnAOB protein abundances (75.7% ± 3.3%) remained stable with decreased temperature. Key proteins of Ca. Brocadia for nitrogen metabolism, as well as for carbohydrate metabolism and primary metabolite biosynthesis were less expressed at 15 °C than 35 °C, while several proteins of heterotrophic Chloroflexi spp. involved in carbohydrate and metabolites metabolisms were expressed to a higher degree at 15 °C. Overall, metabolism of AnAOB responded at a higher degree to low temperatures than that of heterotrophs.
Related Concept Videos
Metabolism of Chemolithotrophs
Overview of Nitrogen Metabolism
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
Inorganic Nitrogen Assimilation
Amino Acid Catabolism
Microbial Nutrition
Carbon-dioxide Fixation


