Biodegradation and enzymatic responses in the marine diatom Skeletonema costatum upon exposure to 2,4-dichlorophenol.
The biodegradation and responses of selected detoxification and antioxidant enzymes in the marine diatom, Skeletonema costatum, upon exposure to sublethal concentrations of 2,4-dichlorophenol (2,4-DCP) were investigated. Results show that 2,4-DCP was readily metabolised, but bioaccumulation and adsorption were negligible. Glutathione S-transferase, ascorbate peroxidase and superoxide dismutase activities were increased markedly after exposure to 2,4-DCP for 96 h, while no appreciable change in peroxidase activity was observed. The addition of exogeneous glutathione to diatom culture enhanced the degradation of 2,4-DCP, and promoted diatom growth. The inhibition of glutathione synthesis enhanced the toxicity of 2,4-DCP. These results suggest that glutathione conjugation was one of the principal mechanisms involved in the degradation of 2,4-DCP in this diatom.
Department of Biology and Chemistry, Centre for Coastal Pollution and Conservation, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, Hong Kong, China.
Shao
S
Yang
Rudolf S S
RS
Wu
Richard Y C
RY
Kong
D000327:Adsorption; D000818:Animals; D000871:Anthelmintics; D060387:Ascorbate Peroxidases; D001673:Biodegradation, Environmental; D002733:Chlorophenols / Q000378:metabolism / Q000493:pharmacokinetics / Q000633:toxicity*; D017377:Diatoms / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D005978:Glutathione / Q000008:administration & dosage / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D014018:Tissue Distribution
D000871:Anthelmintics; D002733:Chlorophenols; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D013482:Superoxide Dismutase; D005982:Glutathione Transferase; D005978:Glutathione; D005947:Glucose; C004762:2,4-dichlorophenol