Detoxification of hydroxylated polychlorobiphenyls by Sphingomonas sp. strain N-9 isolated from forest soil. (December 2016)

• Record Type: Journal Article
• Authors: Mizukami-Murata, Satomi; Sakakibara, Futa; Fujita, Katsuhide; Fukuda, Makiko; Kuramata, Masato; Takagi, Kazuhiro
• Is Part Of: Chemosphere. Volume 165(2016)
• Page Start: 173
• Page End: 182
• Publication Date: 2016-12
• Subjects: Biodegradation -- Hydroxylated PCBs -- Sphingomonas -- Toxicity evaluation -- PC12 cells; CBA chlorobenzoic acids -- 4-CBA 4-chlorobenzoic acid -- 3, 4-CBA 3, 4-chlorobenzoic acid -- DMEM Dulbecco's modified Eagle's medium -- DMSO dimethyl sulfoxide -- ECD-GC electron capture-detector gas chromatograph -- HPLC high-pressure liquid chromatography -- LC-ESI(−)-MS-MS liquid chromatography electrospray ionization-negative mass spectrometry -- KC300 Kanechlor 300 -- LDH lactate dehydrogenase -- MM mineral salt medium -- NGF nerve growth factor -- OH-PCBs hydroxylated polychlorobiphenyls -- OH-CBAs chloro-hydroxybenzoic acids -- 4OH-2CB 4-hydroxy-2-dichlorobiphenyl -- 4OH-3CB 4-hydroxy-3-chlorobiphenyl -- 4OH-4′CB 4-hydroxy-4′-chlorobiphenyl -- 4OH-5CB 4-hydroxy-5-chlorobiphenyl -- 4OH-3, 5CB 4-hydroxy-3, 5-dichlorobiphenyl -- 4OH-2′, 3, 5CB 4-hydroxy-2′, 3, 5′-trichlorobiphenyl -- 4OH-2′, 4′, 6′CB 4-hydroxy-2′, 4′, 6′-trichlorobiphenyl -- 4OH-2′, 3, 4′, 6′CB 4-hydroxy-2′, 3, 4′, 6′-tetrachlorobiphenyl -- 4OH-2′, 3, 4′, 5, 6′CB 4-hydroxy-2′, 3, 4′, 5, 6′-pentachlorobiphenyl -- 4OH-2′, 3, 3′4′, 5, 5′CB 4-hydroxy-2′, 3, 3′4′, 5, 5′-hexachlorobiphenyl -- 4OH-3CBA 3-chloro-4-hydroxybenzoic acid -- 4OH-3, 5CBA 3, 5-chloro-4-hydroxybenzoic acid -- PCBs polychlorinated biphenyls -- PCB#8 2, 4′-dichlorobiphenyl -- PCB#18 2, 2′, 5-trichlorobiphenyl -- PCB#33 2, 3′, 4′-trichlorobiphenyl -- THs thyroid hormones -- UPLC ultra-performance liquid chromatography -- YE yeast extract; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2016.08.127
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: To examine the biodegradation of hydroxylated polychlorobiphenyls (OH-PCBs), we isolated Sphingomonas sp. strain N-9 from forest soil using mineral salt medium containing 4-hydroxy-3-chlorobiphenyl (4OH-3CB) at the concentration of 10 mg/L. Following incubation with strain N-9, the concentration of 4OH-3CB decreased in inverse proportion to strain N-9 proliferation, and it was converted to 3-chloro-4-hydroxybenzoic acid (4OH-3CBA) after 1 day. We observed that strain N-9 efficiently degraded lowly chlorinated OH-PCBs (1–4 Cl), while highly chlorinated OH-PCBs (5–6 Cl) were less efficiently transformed. Additionally, strain N-9 degraded PCBs and OH-PCBs with similar efficiencies, and the efficiency of OH-PCB degradation was dependent upon the positional relationships between OH-PCB hydroxyl groups and chlorinated rings. OH-PCB biodegradation may result in highly toxic products, therefore, we evaluated the cytotoxicity of two OH-PCBs [4OH-3CB and 4-hydroxy-3, 5-dichlorobiphenyl (4OH-3, 5CB)] and their metabolites [4OH-3CBA and 3, 5-chloro-4-hydroxybenzoic acid (4OH-3, 5CBA)] using PC12 rat pheochromocytoma cells. Our results revealed that both OH-PCBs induced cell membrane damage and caused neuron-like elongations in a dose-dependent manner, while similar results were not observed for their metabolites. These results indicated that strain N-9 can convert OH-PCBs into chloro-hydroxybenzoic acids having lower toxicity. Graphical abstract: Highlights: Sphingomonas sp. strain N-9 utilizes chlorinated OH-PCBs and PCBs having 1–4 Cl. Strain N-9 degrades OH-PCBs and PCBs at imbalanced positions of chlorobiphenyl rings. Strain N-9 converts OH-PCBs into chloro-hydroxybenzoic acids having lower toxicity.