Abstract
ABSTRACT
Different compounds can induce stress response by targeting specific genes. Studies related to elucidating the detoxification and adaptive responses of proteins like glutathione‐s‐transferase (GST) can be helpful in better understanding toxicity. Roxarsone and arsanilic acid, which have been exhaustively used as animal and poultry feed additives, pose a threat to the environment and human health. GST enzyme bioassay revealed fluctuations in response to different concentrations of roxarsone and arsanilic acid at different time intervals. The highest GST enzyme activity (40.51%) was observed on day 15 of treatment with roxarsone. On the other hand, arsanilic acid caused the maximum enzyme activity (52.11%) on day 10 of treatment. During this study, the full‐length gene sequence of GST, having the size 984 bp (Genbankno. HQ693699), was achieved from Eisenia fetida and established as a biomarker to assess the toxicity of roxarsone and arsanilic acid. The deduced protein has a computed molecular mass of 23.56 kDa and a predicted isoelectric point of 9.92. Quantitative real‐time PCR revealed significant differential gene expression in response to roxarsone and arsanilic acid treatment as compared with control treatment. Roxarsone caused the highest gene expression of 7.0‐fold increase over control on day 15 of treatment, whereas arsanilic acid resulted in the highest gene expression reaching to 14.56‐fold as compared with control. This study is helpful in understanding the role of GST as a potential biomarker for chemicals like roxarsone and arsanilic acid, which can pollute the food chain. Copyright © 2012 John Wiley & Sons, Ltd.
Glutathione‐S‐transferase has been evaluated as a potential biomarker during this study against the chemicals like roxarsone and arsanilic acid which pollute the environment by degrading into arsenic. During this study, full‐length gene sequence of GST, having the size 984 bp was achieved from Eisenia fetida. The protein has a computed molecular mass of 23.56 kDa and a predicted isoelectric point of 9.92. Enzyme analysis and QRT‐PCR revealed significant differences in activities in response to roxarsone and arsanilic acid treatments as compared to control treatment.