Biological Nitrogen Removal Database
A manually curated data resource for microbial nitrogen removal
Biological Nitrogen Removal Database
A manually curated data resource for microbial nitrogen removal
Influent:Seawater
Denitrification system:Sulfur-driven denitrification (SDN) systems
Denitrifying reactor:SDN reactor
Medium:Sterivex filter
Culture taken from:Thiobacillus thioparus; strains of the Epsilonproteobacterium Sulfurimonas; Gammaproteobacterial sulfur oxidizers of the Thiotrichales and Chromatiales, and a relative of Sedimenticola thiotaurini
Organism (s) cultured:nan
Respiration:Anaerobic
Electron donor:Sulfur; Aragonite
Electron acceptor:Nitrate
Input NO3-N (mg/l):nan
Nitrate removal rate (mg NO3-N/l/h):nan
Denitrification rate (gNO3-N removed/m3/day):nan
Microorganisms identified:Consortium
Molecular tools:16S rRNA gene; Shotgun DNA; RNA sequencing
Major findings:A consortium of denitrifers capabale of coupling sulfur oxidation to denintrification was identified suggesting there is a potential dependencies amongst the SDN members in the denitrification system. These results provide a framework for potential manipulation of SDN reactor systems to maximize nitrate removal efficiency by adjusting physical parameters, changing the hydraulic retention time and microbial seeding.
Authors:Burns et al., 2018
Title:Broad Phylogenetic Diversity Associated With Nitrogen Loss Through Sulfur Oxidation in a Large Public Marine Aquarium.
Pubmed link:Link
Full research link:Link
Abstract:Denitrification by sulfur-oxidizing bacteria is an effective nitrate removal strategy in engineered aquatic systems. However, the community taxonomic and metabolic diversity of sulfur-driven denitrification (SDN) systems, as well as the relationship between nitrate removal and SDN community structure, remains underexplored. This is particularly true for SDN reactors applied to marine aquaria, despite the increasing use of this technology to supplement filtration. We applied 16S rRNA gene, metagenomic, and metatranscriptomic analyses to explore the microbial basis of SDN reactors operating on Georgia Aquarium's Ocean Voyager, the largest indoor closed-system seawater exhibit in the United States. The exhibit's two SDN systems vary in water retention time and nitrate removal efficiency. The systems also support significantly different microbial communities. These communities contain canonical SDN bacteria, including a strain related to Thiobacillus thioparus that dominates the system with the higher water retention time and nitrate removal but is effectively absent from the other system. Both systems contain a wide diversity of other microbes whose metagenome-assembled genomes contain genes of SDN metabolism. These include hundreds of strains of the epsilonproteobacterium Sulfurimonas, as well as gammaproteobacterial sulfur oxidizers of the Thiotrichales and Chromatiales, and a relative of Sedimenticola thiotaurini with complete denitrification potential. The SDN genes are transcribed and the taxonomic richness of the transcript pool varies markedly among the enzymatic steps, with some steps dominated by transcripts from noncanonical SDN taxa. These results indicate complex and variable SDN communities that may involve chemical dependencies among taxa as well as the potential for altering community structure to optimize nitrate removal.