Some data are reported on the biological effects of an excess of copper and cadmium on axenic cultures of Euglena gracilis. Copper does not affect growth, whereas cadmium inhibits it. Copper is excreted by the cells linked to a glycopeptide of a low molecular weight and cadmium is sequestred by a protein of high molecular weight. This protein is not excreted and therefore cadmium is more toxic than copper. The data fit a regulatory model that can be applied also to other compounds like thioneins.
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Con il contributo del Ministero per i Beni e le Attività Culturali