Culture-Dependent and -Independent Identification of Polyphosphate-Accumulating <i>Dechloromonas</i> spp. Predominating in a Full-Scale Oxidation Ditch Wastewater Treatment Plant

Abstract

The oxidation ditch process is one of the most economical approaches currently used to simultaneously remove organic carbon, nitrogen, and also phosphorus (P) from wastewater. However, limited information is available on biological P removal in this process. In the present study, microorganisms contributing to P removal in a full-scale oxidation ditch reactor were investigated using culture-dependent and -independent approaches. A microbial community analysis based on 16S rRNA gene sequencing revealed that a phylotype closely related to Dechloromonas spp. in the family Rhodocyclaceae dominated in the oxidation ditch reactor. This dominant Dechloromonas sp. was successfully isolated and subjected to fluorescent staining for polyphosphate, followed by microscopic observations and a spectrofluorometric analysis, which clearly demonstrated that the Dechloromonas isolate exhibited a strong ability to accumulate polyphosphate within its cells. These results indicate the potential key role of Dechloromonas spp. in efficient P removal in the oxidation ditch wastewater treatment process.

Improved Isolation of Uncultured Anaerobic Bacteria using Medium Prepared with Separate Sterilization of Agar and Phosphate

“…c The novelty index was calculated as "the number of novel phylotypes/total number of isolates". the present study (Terashima et al, 2016), the phylotype YS37 may be a previously unidentified bacterium with high phosphate removal activity. Furthermore, the phylotypes YS38 and YS76, which were also isolated only from PS media under nitrate reduction and fermentation conditions, respectively, showed low sequence identities to known isolated species (88.9% identity to Acidovorax caeni and 90.5% identity to Ornithinimicrobium algicola) (Table S1).…”

“…Sludge from the oxidation ditch plant treating domestic wastewater in Okishima, Omihachiman, Shiga, Japan, was used as the microbial source. This plant is operated with a repetitive cycle of aerobic and anaerobic phases, and has been shown to contain diverse aerobic and both facultative and obligate anaerobic microorganisms (Terashima et al, 2016). The plant operating conditions and sampling procedures were described previously (Terashima et al, 2016).…”

“…This plant is operated with a repetitive cycle of aerobic and anaerobic phases, and has been shown to contain diverse aerobic and both facultative and obligate anaerobic microorganisms (Terashima et al, 2016). The plant operating conditions and sampling procedures were described previously (Terashima et al, 2016). The sludge sample was suspended in sterilized saline (0.9% NaCl) and diluted in a 10-fold series.…”

Metagenomic Insights into the Effects of Seasonal Temperature Variation on the Activities of Activated Sludge

“…Opitutus involved in nitrogen cycling [40]. Candidatus Accumulibacter and Dechloromonas involved in biological phosphorus removal [41,42]. It is interesting that the dominant genera in the AS sample A 6 was almost identical with those existed in the AS sample A 3 when the water temperature increased from 5 • C to 20 • C on the 63rd day.…”

Analysis of Microbial Community Dynamics during the Acclimatization Period of a Membrane Bioreactor Treating Table Olive Processing Wastewater

“…These three OTUs were effectively eliminated from the later samples. Betaproteobacteria, comprising 18% of the Day0 sample were dominated (>99%) by a single genus, Dechloromonas spp., a facultative aerobic, nitrate-reducing organism frequently encountered in WWT plants with a capacity to accumulate polyphosphate [43] (Figure 6). Its presence diminished in the MBR while another member of the Rhodocyclaceae family, Thauera spp.…”