title: Molecular characterization of anaerobic sulfur-oxidizing microbial communities in up-flow anaerobic sludge blanket reactor treating municipal sewage.
abstract: A novel wastewater treatment system consisting of an up-flow anaerobic sludge blanket (UASB) reactor and a down-flow hanging sponge (DHS) reactor with sulfur-redox reaction was developed for treatment of municipal sewage under low-temperature conditions. In the UASB reactor, a novel phenomenon of anaerobic sulfur oxidation occurred in the absence of oxygen, nitrite and nitrate as electron acceptors. The microorganisms involved in anaerobic sulfur oxidation have not been elucidated. Therefore, in this study, we studied the microbial communities existing in the UASB reactor that probably enhanced anaerobic sulfur oxidation. Sludge samples collected from the UASB reactor before and after sulfur oxidation were used for cloning and terminal restriction fragment length polymorphism (T-RFLP) analysis of the 16S rRNA genes of the bacterial and archaeal domains. The microbial community structures of bacteria and archaea indicated that the genus Smithella and uncultured bacteria within the phylum Caldiserica were the dominant bacteria groups. Methanosaeta spp. was the dominant group of the domain archaea. The T-RFLP analysis, which was consistent with the cloning results, also yielded characteristic fingerprints for bacterial communities, whereas the archaeal community structure yielded stable microbial community. From these results, it can be presumed that these major bacteria groups, genus Smithella and uncultured bacteria within the phylum Caldiserica, probably play an important role in sulfur oxidation in UASB reactors.
authors.affiliation: Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka-machi, Nagaoka, Niigata 940-2188, Japan; Halal Products Research Institute, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Azrina A
authors.initials: AA
authors.lastname: Aida
authors.affiliation: Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka-machi, Nagaoka, Niigata 940-2188, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Hatamoto
authors.affiliation: Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka-machi, Nagaoka, Niigata 940-2188, Japan.
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Yamamoto
authors.affiliation: Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka-machi, Nagaoka, Niigata 940-2188, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Ono
authors.affiliation: Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka-machi, Nagaoka, Niigata 940-2188, Japan.
authors.forename: Akinobu
authors.initials: A
authors.lastname: Nakamura
authors.affiliation: Department of Civil and Environmental Engineering, Tohoku University, 6-6-06 Aoba, Sendai, Miyagi 980-8579, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka-machi, Nagaoka, Niigata 940-2188, Japan. Electronic address: ecoya@vos.nagaokaut.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamaguchi
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D019149:Bioreactors / Q000382:microbiology*; D010084:Oxidation-Reduction; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology*; D013455:Sulfur / Q000378:metabolism*; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology
chemical_list: D012336:RNA, Ribosomal, 16S; D012722:Sewage; D013455:Sulfur; D062065:Wastewater
keywords: Anaerobic sulfur oxidation; Microbial community; Molecular analysis; Up-flow anaerobic sludge blanket; Wastewater treatment