Project description:Roothans et al., analyzed heterotrophic denitrification processes that can be an important source of nitrous oxide. We employed planktonic nitrification-inhibited denitrifying enrichment cultures under alternating oxic-anoxic conditions. The dynamic conditions resulted in a general presence of the denitrifying enzymes. Overall, we show that aerobic denitrification should not be neglected as an ecologically relevant process. Contact author: m.laureni@tudelft.nl
2024-07-17 | PXD042057 | Pride
Project description:Influence of heterotrophic nitrifying/aerobic denitrifying bacterial communities on nitrogen removal from decentralized domestic wastewaters in pilot-scale tidal flow constructed wetlands
| PRJNA559475 | ENA
Project description:Heterotrophic nitrification aerobic denitrification bacteria for high salt wastewater treatment
Project description:This study systematically evaluated the denitrification performance and tolerance mechanisms of the highly efficient heterotrophic nitrifying–aerobic denitrifying strain Klebsiella sp. WH-E under Zn²⁺ stress. Under 100 mg/L Zn²⁺ stress, the heterotrophic nitrification and aerobic denitrification capabilities of Klebsiella sp. WH-E resulted in an ammonia nitrogen removal rate of 95.53% and a nitrate nitrogen removal rate of 74.00%. and the nitrite nitrogen removal rate was 72.75%. The activities of the key denitrification enzymes NAR and NIR remained largely stable, and the accumulation of NO₃⁻-N and NO₂⁻-N during nitrogen transformation was limited. Multi-omics analysis revealed that Zn²⁺ stress significantly upregulated nitrogen metabolism-related genes (narG, nirB) and metal homeostasis regulatory genes (zntA, arsR, czcC), while simultaneously regulating ABC transporters and two-component systems to maintain intracellular Zn²⁺ homeostasis. The abundance of sulfur metabolism and antioxidant-related metabolit
Project description:Nitrogen and arsenic contaminants often coexist in groundwater, and microbes show the potential for simultaneous removal of nitrogen and arsenic. Here, we reported that Hydrogenophaga sp. H7 was heterotrophic nitrification and aerobic denitrification (HNAD) and arsenite [As(III)] oxidation bacterium. Strain H7 presented efficient capacities for simultaneous NH4+-N, NO3--N, or NO2--N removal with As(III) oxidation during aerobic cultivation. Strikingly, the bacterial ability to remove nitrogen and oxidize As(III) has remained high across a wide range of temperatures, pH values, and shaking speeds, exceeding that of the most commonly reported HNAD bacteria. Additionally, the previous HNAD strains exhibited a high denitrification efficiency, but a suboptimal concentration of nitrogen remained in the wastewater. Here, strain H7 combined with FeCl3 efficiently removed 96.14% of NH4+-N, 99.08% of NO3--N, and 94.68% of total nitrogen (TN), and it oxidized 100% of As(III), even at a low nitrogen concentration (35 mg/L). The residues in the wastewater still met the Surface Water Environmental Quality Standard of China after five continuous wastewater treatment cycles. Furthermore, genome and proteomic analyses led us to propose that the shortcut nitrification-denitrification pathway and As(III) oxidase AioBA are the key pathways that participate in simultaneous nitrogen removal and As(III) oxidation.
2022-12-09 | PXD038710 |
Project description:investigate tidal flow constructed wetland microbial community diversity