title: A role of Bradyrhizobium elkanii and closely related strains in the degradation of methoxychlor in soil and surface water environments.
abstract: We have reported that a leguminous bacterial strain, Bradyrhizobium sp. strain 17-4, isolated from river sediment, phylogenetically very close to Bradyrhizobium elkanii, degraded methoxychlor through O-demethylation and oxidative dechlorination. In the present investigation, we found that B. elkanii (USDA94), a standard species deposited in the Culture Collection, degraded methoxychlor. Furthermore, Bradyrhizobium sp. strain 4-1, also very close to B. elkanii, isolated from Japanese paddy field soil, degraded methoxychlor. These B. elkanii and closely related strains degraded methoxychlor through almost identical metabolic pathways, and cleaved the phenyl ring and mineralized. In contrast, another representative Bradyrhizobium species, B. japonicum (USDA110), did not degrade methoxychlor at all. Based on these findings, B. elkanii and closely related strains are likely to play an important role not only in providing the readily biodegradable substrates but also in completely degrading (mineralizing) methoxychlor by themselves in the soil and surface water environment.
authors.affiliation: The Institute of Environmental Toxicology.
authors.forename: Koji
authors.initials: K
authors.lastname: Satsuma
authors.forename: Minoru
authors.initials: M
authors.lastname: Masuda
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Sato
mesh_terms: D001673:Biodegradation, Environmental; D001711:Biotransformation; D020369:Bradyrhizobium / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004785:Environmental Pollutants / Q000378:metabolism*; D007700:Kinetics; D053858:Metabolic Networks and Pathways; D008731:Methoxychlor / Q000378:metabolism*; D012988:Soil Microbiology; D013045:Species Specificity; D014871:Water Microbiology
chemical_list: D004785:Environmental Pollutants; D008731:Methoxychlor