title: Degradation of estrogens by Rhodococcus zopfii and Rhodococcus equi isolates from activated sludge in wastewater treatment plants.
abstract: We have isolated four strains of Rhodococcus which specifically degrade estrogens by using enrichment culture of activated sludge from wastewater treatment plants. Strain Y 50158, identified as Rhodococcus zopfii, completely and rapidly degraded 100 mg of 17beta-estradiol, estrone, estriol, and ethinyl estradiol/liter, as demonstrated by thin-layer chromatography and gas chromatography-mass spectrometry analyses. Strains Y 50155, Y 50156, and Y 50157, identified as Rhodococcus equi, showed degradation activities comparable with that of Y 50158. Using the random amplified polymorphism DNA fingerprinting test, these three strains were confirmed to have been derived from different sources. R. zopfii Y 50158, which showed the highest activity among these four strains, revealed that the strain selectively degraded 17beta-estradiol during jar fermentation, even when glucose was used as a readily utilizable carbon source in the culture medium. Measurement of estrogenic activities with human breast cancer-derived MVLN cells showed that these four strains each degraded 100 mg of 17beta-estradiol/liter to 1/100 of the specific activity level after 24 h. It is thus suggested that these strains degrade 17beta-estradiol into substances without estrogenic activity.
authors.affiliation: Yakult Central Institute for Microbiological Research, 1796 Yaho, Kunitachi, Tokyo 186-8650, Japan. takeshi-yoshimoto@yakult.co.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yoshimoto
authors.forename: Fumiko
authors.initials: F
authors.lastname: Nagai
authors.forename: Junji
authors.initials: J
authors.lastname: Fujimoto
authors.forename: Koichi
authors.initials: K
authors.lastname: Watanabe
authors.forename: Harumi
authors.initials: H
authors.lastname: Mizukoshi
authors.forename: Takashi
authors.initials: T
authors.lastname: Makino
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Kimura
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Saino
authors.forename: Haruji
authors.initials: H
authors.lastname: Sawada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Omura
mesh_terms: D001673:Biodegradation, Environmental; D004967:Estrogens / Q000493:pharmacokinetics*; D007700:Kinetics; D010802:Phylogeny; D012240:Rhodococcus / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D016929:Rhodococcus equi / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid
chemical_list: D004967:Estrogens; D012722:Sewage