Microbial community of biological phosphorus removal process fed with municipal wastewater under different electron acceptor conditions.
The microbial community in a biological phosphorus removal process under different electron acceptor conditions was estimated by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) assay and principal-component analysis (PCA). For this purpose, a lab-scale sequencing batch reactor (SBR) fed with municipal wastewater was operated under anaerobic-aerobic, anaerobic-anoxic-aerobic and anaerobic-anoxic conditions. The results of PCR-DGGE targeting the 16S rRNA gene indicated a significant shift in the microbial community with electron acceptor conditions. From the 16S rRNA-based PCA, the microbial shift implies that little oxygen supply caused the deterioration of aerobic bacteria, including aerobic polyphosphate-accumulating organisms (PAOs). Moreover, it also reflects the existence of nitrate-utilizing denitrifiers. On the other hand, although the band patterns of DGGE targeting a functional gene of denitrification (nirS) also showed the microbial shift, the result of PCA differed from that of 16S rRNA-based analysis. There is no conclusive proof that the bacteria represented as the dominant bands detected in the present study are denitrifying-PAOs so far, it should be worthwhile to identify the detected bacteria and to examine their traits as new denitrifying-PAO candidates.
Shoji
T
T
Department of Urban Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 Japan. shoji77@pwri.go.jp
Nittami
T
T
Onuki
M
M
Satoh
H
H
Mino
T
T
D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D017931:DNA Primers; D004583:Electrons; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D052918:Environmental Restoration and Remediation; D007220:Industrial Waste; D010758:Phosphorus / Q000302:isolation & purification* / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014874:Water Pollutants, Chemical / Q000302:isolation & purification* / Q000378:metabolism
D017931:DNA Primers; D007220:Industrial Waste; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D010758:Phosphorus