title: Community structure of a sulfate-reducing consortium in lead-contaminated wastewater treatment process.
abstract: This study evaluated the capacity to remove lead by an indigenous consortium of five sulfate-reducing bacteria (SRB): Desulfobacterium autotrophicum, Desulfomicrobium salsugmis, Desulfomicrobium escambiense, Desulfovibrio vulgaris, and Desulfovibrio carbinolicus, using continuous moving bed biofilm reactor systems. Four continuous moving bed biofilm reactors (referred as R1-R4) were run in parallel for 40 days at lead loading rates of 0, 20, 30 and 40 mg l-1day-1, respectively. The impact of lead on community structure of the SRB consortium was investigated by dsrB gene-based denaturing gradient gel electrophoresis (dsrB-based DGGE), fluorescence in situ hybridization (FISH) and chemical analysis. These results indicated that D. escambiense and D. carbinolicus were dominant in all analyzed samples and played a key role in lead removal in R2 (20 mg l-1day-1) and R3 (30 mg l-1day-1). However, in R4 (40 mg l-1day-1), these two strains were barely detected by FISH and dsrB-based DGGE. As a result, SRB activity was severely affected by lead toxicity. High lead removal efficiencies of lead (99-100%) were observed in R2 and R3 throughout the operation, whereas that in R4 was significantly decreased (91%) after 40 days of operation. This data strongly implied that the investigated SRB consortium might have potential application for lead removal. Moreover, to improve the efficiency of the lead treatment process, the lead loading rates below the inhibitory level to SRB activity should be selected.
authors.affiliation: Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam.
authors.forename: Yen T
authors.initials: YT
authors.lastname: Nguyen
authors.affiliation: Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam. ktquynhhoa@ibt.ac.vn.
authors.forename: Hoa T Q
authors.initials: HT
authors.lastname: Kieu
authors.affiliation: Engler-Bunte-Institut, Chair of Water Chemistry and Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, 76131, Karlsruhe, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: West
authors.affiliation: Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam.
authors.forename: Yen T
authors.initials: YT
authors.lastname: Dang
authors.affiliation: Engler-Bunte-Institut, Chair of Water Chemistry and Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, 76131, Karlsruhe, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Horn
mesh_terms: D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D017404:In Situ Hybridization, Fluorescence; D007854:Lead / Q000378:metabolism*; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D016999:Sulfur-Reducing Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D062065:Wastewater / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D004269:DNA, Bacterial; D007854:Lead; D012336:RNA, Ribosomal, 16S; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Denaturing gradient gel electrophoresis; Fluorescent in situ hybridization; Lead removal; Sulfate-reducing bacteria; dsrB gene