Intracellular Changes Evoked by Cadmium Incorporation on Saccharomyces cerevisiae Yeast
MOREIRA, L. M. C .; MENEZES; M. A. B. C.;AMARAL, A. M. AND NEVES, M.J.
Centro de Desenvolvimento da Tecnologia Nuclear CDTN/CNEN
Heavy metals are recognised as environmental pollutants and are released from both industrial and agricultural sources and these activities leads to an accumulation of metal ions. Cadmium is the one of the most toxic agent for human, animal, plants and environment. This heavy metal is extremely toxic in low concentrations and causes serious pathologies and problems to the health. New alternatives for heavy metal removal of the effluent industrials have been widely investigated. Bioremediation is a technique that uses microorganisms, in metal removal of the environment. The aim of the present work is to evaluate the cadmium incorporation by Saccharomyces cerevisiae (W303-WT). Capacity of cadmium absorption and some biochemistry changes associated to the bioaccumulation of this metal were studied in Saccharomyces cerevisiae W303-WT cells incubated in cadmium chloride presence (10, 25, 50, 75 and 100ppm). Cadmium inhibited the growth of cells, when compared with the controlled condition (cadmium absence). The gradual increase of the cadmium concentrations provides an intracellular accumulation of trehalose. It was verified, by neutronic activation, the capacity of cadmium incorporation (50ppm and 800ppm) of the cells which were collected at logarithmic phase or stationary of the growth. It was observed that with an increase of cadmium concentration a higher increase in the incorporation of the metal occurred. Alterations in the sodium and potassium levels have been observed when the cells incorporate cadmium.
Financial support: CNEN/CDTN
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