フェノールによるトリクロロエチレンのコメタボリズムにおいて出現する微生物群の解析

抄録

Laboratory scale soilc olumns were operated to degrade trichloroethylen (TCE) by co-metabolism with phenol. The columns were operated approximately for a year. At the end of the operation effluent and biofilm samples were taken to analyze microbial community by three methods. First, dominant phenol-utilizing strains were isolated from diluted tubes in most-probable-numbe (MPN) methods. Totally four strains were isolated, and only one strain showed the capability of degrading TCE with phenol induction. Phylogenetic analysis on these four strains was carried out, and each of four strains was found to exist at separated positions in a phylogenetic tree, suggesting the existence of variety of phenol utilizers in the columns. Second, clones of PCR-amplified 16S rDNAs were randomly obtained and analyzed. Both of suspended and attached microbialc ommunitiesc onsisted of severald ominantt ypes of 16S rDNA occupyinga pproximately 50% of total 16S rDNA clones. Furthermore, two types of 16S rDNA showed identical phylotypes, which were defined by restriction patterns, among two microbial communities. Third, rapid analysis of total microbial populations was conducted by 5' terminal restriction fragment length polymorphism (T-RFLP) of 16S rDNAs. Results of T-RFLP analysis well characterized the microbial communities, and made possible to determine a dominant 16S rDNA type in a short time.