ABSTRACT: Enhanced nitrogen removal through bioaugmentation with Stutzerimonas stutzeri SW22: From denitrification mechanism to optimized sequencing batch reactor
Project description:A1501 NFI is a genomic island derived from Pseudomonas stutzeri A1501. To study the molecular interactions of the P. stutzeri nif genes with the E. coli genome during nitrogen fixation, the NIF of A1501 was transferred into E. coli and comparative transcriptomics analyses were performed between nitrogen fixation conditions and nitrogen excess conditions.
2015-08-05 | GSE37780 | GEO
Project description:Enhanced nitrogen removal through rapid biofilm formation by strain XN-1 immobilized carriers in sequencing batch biofilm reactor
Project description:Polyphosphate accumulating organisms are responsible for enhanced biological phosphate removal from wastewater, where they grow embedded in a matrix of extracellular polymeric substances. Little is known about the composition and dynamics of those proteins and their production by the different microorganisms. Tomás-Martínez et al., (2022) studied the turnover of proteins and polysaccharides in extracellular polymeric fractions of an enrichment culture of polyphosphate accumulating organisms using an anaerobic-aerobic sequencing batch reactor simulating EBPR conditions. Finally, the carbon source was switched to 13C-labelled acetate to study the protein turnover. Samples were collected at the end of each aerobic phase.
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.
