Mercury intake through fish consumption in riverside populations of Amazon: Evaluation of biomarkers, of effect and selenium influence .

Abstract

The present proposal aims to identify protein and/or enzymatic biomarkers of mercury exposure in the species Mylossoma spp (pacu, non-carnivorous species) and Cichla sp. (tucunaré, carnivorous species) from the middle Rio Negro/Amazonas region, through the metalloproteomic study and the mechanisms involved in the oxidative stress of these fish species. A study of the mitigating effect of selenium on the action of mercury in the fish organism will be carried out too. To achieve the proposed objectives, metalloproteomic strategies (2D PAGE, GFAAS, LC-ESI-MS/MS and Bioinformatics) and bioanalytical methods will be used to: - Fractionate the proteome of muscle and liver tissue samples of Mylossoma spp and Cichla sp.; - Map mercury and selenium in protein spots of the 2D PAGE gels; - Characterize the protein spots associated with mercury and selenium in the muscle and liver proteome; - Evaluate the oxidative stress of Mylossoma spp and Cichla sp. contaminated with mercury, by determining the activities of enzymes of the first line of antioxidant defense (SOD, CAT and GPx) and the concentration of lipoperoxide (LPO); - Identify mercury-associated proteins and differentially by Shotgun - LC-MS/MS; - Perform functional analysis of metal binding proteins associated with Hg and Se using Blast2GO, Cytoscape and DAVID softwares. Based on the characterization results of metal binding proteins and their functional analysis, it is expected to elect possible biomarkers of exposure to mercury in the species Mylossoma spp and Cichla sp., as well as contribute with information to elucidate the mitigating effect of selenium in relation mercury toxicity in fish.