Enrichment Using an Up-flow Column Reactor and Community Structure of Marine Anammox Bacteria from Coastal Sediment

Abstract

We established an enrichment culture of marine anaerobic ammonium oxidation (anammox) bacteria using an upflow column reactor fed with artificial sea water supplemented with nitrogen and minerals and inoculated with coastal surface sediment collected from Hiroshima Bay. After 2 months of reactor operation, simultaneous removal of NH4 + and NO2− was observed, suggesting that an anammox reaction was proceeding. A total nitrogen removal rate of 2.17 g-N L −1 day −1 was attained on day 594 while the nitrogen loading rate was 3.33 g-N L −1 day −1 . Phylogenetic analysis revealed that at least two dominant "Candidatus Scalindua" species were present in this reactor. Moreover, many uncultured bacteria and archaea, including candidate division or ammonia-oxidizing archaea, were present. Fluorescence in situ hybridization (FISH) revealed that anammox bacteria accounted for 85.5 ± 4.5% of the total bacteria at day 393. We also designed two oligonucleotide probes specific to each dominant "Candidatus Scalindua" species. A simultaneous FISH analysis using both probes showed that two different "Candidatus Scalindua" species were clearly recognizable and coexisted during reactor operation, although there was some variation in their abundance. The marine anammox bacteria enriched in this study have potential applications to the treatment of industrial wastewater containing high levels of ammonium and salt.

Nitrate-Dependent Ferrous Iron Oxidation by Anaerobic Ammonium Oxidation (Anammox) Bacteria

“…Scalindua sp." previously described by Kindaichi et al (27) was inoculated into the MBR, and it was operated for more than half of a year at 20°C with a continuous supply of inorganic nutrient medium containing artificial sea salt (2.5% [wt/vol]; Marine Tech, Tokyo, Japan). Anammox bacteria accounted for more than 90% of the total biomass in the culture, as determined by FISH analysis with the oligonucleotide probe AMX820.…”

“…Experiments were carried out primarily by using an anammox bacterium, "Candidatus Brocadia sinica," that was enriched from activated sludge from a municipal wastewater treatment plant in Japan (25,26). Activity of nitrate-dependent Fe 2ϩ oxidation was also examined in another anammox bacterium, "Candidatus Scalindua sp.," that was originally obtained from marine sediment in Hiroshima Bay, Japan (27,28).…”

Anaerobic Ammonium-Oxidizing Bacteria: Unique Microorganisms with Exceptional Properties

“…"Candidatus Kuenenia" (76), "Candidatus Brocadia" (43,48,86), "Candidatus Anammoxoglobus" (41), and "Candidatus Jettenia" (67a) have all been enriched from activated sludge. The fifth genus, "Candidatus Scalindua" (50,77), has been enriched from natural habitats, especially from marine sediments and oxygen minimum zones (44,45,46,51,64,66,79,96,105). Despite the relatively large phylogenetic distance, all anammox organisms belong to the same order, Brocadiales (34), which forms a monophyletic group, or clade, deeply branching inside the phylum Planctomycetes (78,79,86).…”

Nitrogen Cycling in Rice Paddy Environments: Past Achievements and Future Challenges

“…It is important to note, however, that fungal co-denitrification can also produce 14 N 15 N molecules similar to the anammox process. Since its first discovery in wastewater treatment systems, the anammox process has been reported as a major N2 source in various marine and fresh water and sediments (5,6,19,28,59,66,69,92,153). Anammox bacteria belong to several candidatus genera in the phylum Planctomycetes (113).…”