Detection of a Bacterial Group Within the Phylum Chloroflexi And
Microbes Environ. Vol. 21, No. 3, 154–162, 2006 http://wwwsoc.nii.ac.jp/jsme2/ Detection of a Bacterial Group within the Phylum Chloroflexi and Reductive-Dehalogenase-Homologous Genes in Pentachlorobenzene- Dechlorinating Estuarine Sediment from the Arakawa River, Japan KYOSUKE SANTOH1, ATSUSHI KOUZUMA1, RYOKO ISHIZEKI2, KENICHI IWATA1, MINORU SHIMURA3, TOSHIO HAYAKAWA3, TOSHIHIRO HOAKI4, HIDEAKI NOJIRI1, TOSHIO OMORI2, HISAKAZU YAMANE1 and HIROSHI HABE1*† 1 Biotechnology Research Center, The University of Tokyo, 1–1–1 Yayoi, Bunkyo-ku, Tokyo 113–8657, Japan 2 Department of Industrial Chemistry, Faculty of Engineering, Shibaura Institute of Technology, Minato-ku, Tokyo 108–8548, Japan 3 Environmental Biotechnology Laboratory, Railway Technical Research Institute, 2–8–38 Hikari-cho, Kokubunji-shi, Tokyo 185–8540, Japan 4 Technology Research Center, Taisei Corporation, 344–1 Nase, Totsuka-ku, Yokohama 245–0051, Japan (Received April 21, 2006—Accepted June 12, 2006) We enriched a pentachlorobenzene (pentaCB)-dechlorinating microbial consortium from an estuarine-sedi- ment sample obtained from the mouth of the Arakawa River. The sediment was incubated together with a mix- ture of four electron donors and pentaCB, and after five months of incubation, the microbial community structure was analyzed. Both DGGE and clone library analyses showed that the most expansive phylogenetic group within the consortium was affiliated with the phylum Chloroflexi, which includes Dehalococcoides-like bacteria. PCR using a degenerate primer set targeting conserved regions in reductive-dehalogenase-homologous (rdh) genes from Dehalococcoides species revealed that DNA fragments (approximately 1.5–1.7 kb) of rdh genes were am- plified from genomic DNA of the consortium. The deduced amino acid sequences of the rdh genes shared sever- al characteristics of reductive dehalogenases.
[Show full text]