title: Rare taxa have potential to make metabolic contributions in enhanced biological phosphorus removal ecosystems.
abstract: Enhanced biological phosphorus removal (EBPR) relies on diverse but specialized microbial communities to mediate the cycling and ultimate removal of phosphorus from municipal wastewaters. However, little is known about microbial activity and dynamics in relation to process fluctuations in EBPR ecosystems. Here, we monitored temporal changes in microbial community structure and potential activity across each bioreactor zone in a pilot-scale EBPR treatment plant by examining the ratio of small subunit ribosomal RNA (SSU rRNA) to SSU rRNA gene (rDNA) over a 120 day study period. Although the majority of operational taxonomic units (OTUs) in the EBPR ecosystem were rare, many maintained high potential activities based on SSU rRNA : rDNA ratios, suggesting that rare OTUs contribute substantially to protein synthesis potential in EBPR ecosystems. Few significant differences in OTU abundance and activity were observed between bioreactor redox zones, although differences in temporal activity were observed among phylogenetically cohesive OTUs. Moreover, observed temporal activity patterns could not be explained by measured process parameters, suggesting that other ecological drivers, such as grazing or viral lysis, modulated community interactions. Taken together, these results point towards complex interactions selected for within the EBPR ecosystem and highlight a previously unrecognized functional potential among low abundance microorganisms in engineered ecosystems.
authors: Department of Civil Engineering, University of British Columbia, Vancouver, BC, Canada.
authors: Christopher E
authors: CE
authors: Lawson
authors: Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada.
authors: Blake J
authors: BJ
authors: Strachan
authors: Graduate Program in Bioinformatics, University of British Columbia, Vancouver, BC, Canada.
authors: Niels W
authors: NW
authors: Hanson
authors: Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada.
authors: Aria S
authors: AS
authors: Hahn
authors: Department of Civil Engineering, University of British Columbia, Vancouver, BC, Canada.
authors: Eric R
authors: ER
authors: Hall
authors: Department of Civil Engineering, University of British Columbia, Vancouver, BC, Canada.|CH2M Hill Canada, 4720 Kingsway Suite 2100, Burnaby, BC, Canada.
authors: Barry
authors: B
authors: Rabinowitz
authors: Department of Civil Engineering, University of British Columbia, Vancouver, BC, Canada.
authors: Donald S
authors: DS
authors: Mavinic
authors: Department of Civil Engineering, University of British Columbia, Vancouver, BC, Canada.|Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada.
authors: William D
authors: WD
authors: Ramey
authors: Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada.|Graduate Program in Bioinformatics, University of British Columbia, Vancouver, BC, Canada.
authors: Steven J
authors: SJ
authors: Hallam
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D004275:DNA, Ribosomal / Q000235:genetics*; D017753:Ecosystem; D010758:Phosphorus / Q000378:metabolism*; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics*; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D004275:DNA, Ribosomal; D010758:Phosphorus; D012335:RNA, Ribosomal; D062065:Wastewater; D014874:Water Pollutants, Chemical