title: Microbial characterization of the biofilms developed for treating ampicillin-bearing wastewater.
abstract: In this study, biofilms were developed in three airlift reactors to treat wastewaters with ampicillin (AMP) of 0, 4 and 8 mg L(-1), respectively. During 60 days of operation, AMP was not found to inhibit the biofilm growth. Denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene sequencing were used to characterize the bacterial community of these biofilms. It was found that the community diversity was lowered, whereas the community stability was enhanced in the biofilm supplemented with AMP as compared to the biofilm free of AMP. Community members were particularly examined in the biofilms developed with 8 mg L(-1) AMP at different stages. Phylogenetic classification revealed that all the identified bacteria fell into four divisions: β-Proteobacteria, α-Proteobacteria, γ-Proteobacteria and Bacteroides. The dominant genus was Acidovorax sp. with an abundance of about 35%. Further analyses on the identification results showed that the quantitative change of AMP-degrading bacteria in the biofilms developed with AMP was positively related to the AMP biodegradation performance.
authors.affiliation: Division of Environmental and Water Resources Engineering, School of Civil and Environmental Engineering, Nanyang Technological University, Singapore.
authors.forename: Liang
authors.initials: L
authors.lastname: Shen
authors.forename: Hailou
authors.initials: H
authors.lastname: Xu
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000667:Ampicillin / Q000032:analysis* / Q000494:pharmacology; D001419:Bacteria / Q000145:classification / Q000235:genetics*; D001483:Base Sequence; D044822:Biodiversity; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D058645:Denaturing Gradient Gel Electrophoresis; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism; D018508:Water Purification / Q000379:methods*
chemical_list: D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D000667:Ampicillin