Project description:In response to the issues of low denitrification efficiency and high N₂O emissions in the biological nitrogen removal process of low C/N municipal wastewater, studies typically address these challenges by adding carbon sources. In this study, the addition of microorganisms enhanced the carbon flow and electron transport for nitrate reduction, significantly improving the denitrification performance of low C/N wastewater and reducing N₂O production. Proteomic analysis was employed to explore the mechanisms underlying this effect. The results revealed that the metabolites produced by the added microorganisms, S. oneidensis MR-1 and B. subtilis, including biosurfactants, heme, and cytochromes, altered the intracellular carbon redistribution in P. denitrificans, leading to an increased carbon flow directed towards nitrate reduction, thus enhancing total nitrogen removal efficiency.
Project description:The effect of nitrate reduction (anaerobic cultivation in the presence of heme, vitamin K2 and nitrate) was compared with anaerobic cultivation supplemented with citrate (Lactobacillus plantarum). The medium was chemically defined medium with mannitol as main carbon source Two-condition experiment, nitrate vs citrate reducing cells. Biological replicates: 4 nitrate reducing cultures, 4 citrate reducing cultures, independently grown and harvested. Two slides were used, each slide contained 8 Arrays. Citrate reducing cultures are called reactor 1-4, Nitrate reducing cultures are called reactor A-D
Project description:Transcriptional profiling of Haloferax mediterranei in three culture media with different nitrogen sources: a) cells were grown stationary and exponentially on ammonium, b) cells were grown exponentially on nitrate, and c) cells were shifted to nitrogen starvation conditions. The main differences in the transcriptional profiles have been identified between the cultures with ammonium as nitrogen source and the cultures with nitrate or nitrogen starvation, supporting previous results which indicate the absence of ammonium as the factor causing the expression of genes involved in nitrate assimilation pathway.
Project description:Transcriptional profiling of Haloferax mediterranei in three culture media with different nitrogen sources: a) cells were grown stationary and exponentially on ammonium, b) cells were grown exponentially on nitrate, and c) cells were shifted to nitrogen starvation conditions. The main differences in the transcriptional profiles have been identified between the cultures with ammonium as nitrogen source and the cultures with nitrate or nitrogen starvation, supporting previous results which indicate the absence of ammonium as the factor causing the expression of genes involved in nitrate assimilation pathway. Four-conditions experiment with four biological replicates, combined in a loop design.
