title: Bacterial activity and community composition in stream water and biofilm from an urban river determined by fluorescent in situ hybridization and DGGE analysis.
abstract: Abstract Physiologic activity and community structure of planktonic and biofilm microbial communities in an urban river were analyzed using 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) staining, fluorescent in situ hybridization (FISH) and denaturing gradient gel electrophoresis (DGGE) analysis of polymerase chain reaction (PCR)-amplified 16S rDNA fragments. Respiring bacteria estimated by CTC reduction were higher in biofilms (20%) than in stream water samples (12%). FISH analysis revealed that bacterial populations in both stream water and biofilms were dominated by beta-Proteobacteria and Cytophaga-Flavobacterium cluster. Microbial community changes determined by multidimensional scaling analysis from DGGE patterns showed that microbial community structures in biofilms matured within 3-7 days of their formation and did not change further, while those in stream water changed continuously.
authors.affiliation: Environmental Science and Microbiology, Graduate School of Pharmaceutical Sciences, Osaka University, 1-6, Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Ruben
authors.initials: R
authors.lastname: Araya
authors.forename: Katsuji
authors.initials: K
authors.lastname: Tani
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Takagi
authors.forename: Nobuyasu
authors.initials: N
authors.lastname: Yamaguchi
authors.forename: Masao
authors.initials: M
authors.lastname: Nasu