title: Cu/Zn-superoxide dismutase and glutathione are involved in response to oxidative stress induced by protein denaturing effect of alachlor in Saccharomyces cerevisiae.
abstract: Alachlor is a widely used pre-emergent chloroacetanilide herbicide which has been shown to have many harmful ecological and environmental effects. However, the mechanism of alachlor-induced oxidative stress is poorly understood. We found that, in Saccharomyces cerevisiae, the intracellular levels of reactive oxygen species (ROS) including superoxide anions were increased only after long-term exposure to alachlor, suggesting that alachlor is not a pro-oxidant. It is likely that alachlor-induced oxidative stress may result from protein denaturation because alachlor rapidly induced an increased protein aggregation, leading to upregulation of SSA4 and HSP82 genes encoding heat shock proteins (Hsp) of Hsp70 and Hsp90 family, respectively. Although only SOD1 encoding Cu/Zn-superoxide dismutase (SOD), but not SOD2 encoding Mn-SOD, is essential for alachlor tolerance, both SODs play a crucial role in reducing alachlor-induced ROS. We found that, after alachlor exposure, glutathione production was inhibited while its utilization was increased, suggesting the role of glutathione in protecting cells against alachlor, which becomes more important when lacking Cu/Zn-SOD. Based on our results, it seems that alachlor primarily causes damages to cellular macromolecules such as proteins, leading to an induction of endogenous oxidative stress, of which intracellular antioxidant defense systems are required for elimination.
authors.affiliation: Department of Biology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; Center of Excellence on Environmental Health and Toxicology, CHE, Ministry of Education, Thailand.
authors.forename: Kasidit
authors.initials: K
authors.lastname: Rattanawong
authors.affiliation: Department of Biology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; Center of Excellence on Environmental Health and Toxicology, CHE, Ministry of Education, Thailand.
authors.forename: Kittikhun
authors.initials: K
authors.lastname: Kerdsomboon
authors.affiliation: Department of Biology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; Center of Excellence on Environmental Health and Toxicology, CHE, Ministry of Education, Thailand. Electronic address: choowong.aue@mahidol.ac.th.
authors.forename: Choowong
authors.initials: C
authors.lastname: Auesukaree
mesh_terms: D000081:Acetamides / Q000494:pharmacology*; D015153:Blotting, Western; D005978:Glutathione / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006540:Herbicides / Q000494:pharmacology*; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects*; D011489:Protein Denaturation; D012333:RNA, Messenger / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism*; D000099156:Superoxide Dismutase 2
chemical_list: D000081:Acetamides; D005978:Glutathione; D006360:Heat-Shock Proteins; D006540:Herbicides; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D013482:Superoxide Dismutase; D000099156:Superoxide Dismutase 2; C000188:alachlor
keywords: Alachlor; Glutathione; Heat shock protein; Oxidative stress; Protein aggregation; Saccharomyces cerevisiae; Superoxide dismutase