title: Microbial community analysis and performance of a phosphate-removing activated sludge.
abstract: The microbial community of a phosphate-removing activated sludge was analyzed according to the extracted 16S rDNA sequences. The sludge, which accumulated 5.6% P by weight, was obtained from a sequencing batch reactor treating a fatty-acid rich wastewater containing 108 mg l(-1) total organic carbon (TOC), 14.0 mg l(-1) N and 16.2 mg l(-1) P. The reactor at 25 degrees C and pH 7.6 removed over 96% TOC and 99.9% P from the wastewater. According to the 16S rDNA analysis of the 114 clones developed, the sludge had a diverse population, mainly comprising Proteobacteria (71.0%) and the Cytophaga Flavobacterium Bacteroides group (23.7%), plus a few species of Planctomycetales (2.6%), Verrucomicrobiales (1.8%) and Firmicutes (0.9%). Of the 114 clones, 36 (31.6%) were closely affiliated with Acinetobacter. However, Acinetobacter did not accumulate phosphate judging from the images of sludge samples hybridized with an Acinetobacter-specific probe and stained with a phosphate-specific dye. The identities of the phosphate-removing bacteria remain unclear.
authors.affiliation: Environmental Biotechnology Laboratory, Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Tong
authors.initials: T
authors.lastname: Zhang
authors.forename: Herbert H P
authors.initials: HH
authors.lastname: Fang
mesh_terms: D001419:Bacteria / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D044822:Biodiversity; D019149:Bioreactors; D003001:Cloning, Molecular; D016000:Cluster Analysis; D017404:In Situ Hybridization, Fluorescence; D007211:Indoles; D008969:Molecular Sequence Data; D010710:Phosphates / Q000032:analysis* / Q000378:metabolism; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000737:chemistry / Q000382:microbiology*; D014865:Waste Disposal, Fluid
chemical_list: D007211:Indoles; D010710:Phosphates; D012336:RNA, Ribosomal, 16S; D012722:Sewage; C007293:DAPI