Title : Metallothionein as mineral ion carrier agent, reducing agent in metabolism and in toxicology
Abstract:
Metallothionein is a biomarker in living systems principally for us humans, intracellular reducing agent also in defense for environmental pollution (high levels in mines workers in China have absence of pathology) and for the presence of heavy metals as cadmium, mercury and lead among others. On the other side Mytilus edulis is a water-sea sensor of pollution with high levels of MT and essential mineral ions, which is extensively produced and important economic product in the autonomous region of Galicia on the Nord-West coast of Spain for local use and to export, and also for the Cantabria north coast of the Iberic Peninsula. MT is a low molecular weight protein (7 kD), without aromatic amino acids, and the 30% of the amino acid residues are cysteines, which allows it to bind both positive essential mineral ions (Fe, Zn, Ca, Cu, etc.) as well as toxic heavy metals (Cd, Hg and Pb as others). Which in turn shows a great affinity for thiol groups (-SH). Cadmium concentration in environmental pollution of Ecosystems is increasing and must be evaluated in order to establish the risk assessment in human health. The thermal stability and the great affinity of MT to Cd2+ ions are due to the high number of negative thiol = -SH ligands and to the final globular structure. Its chemical characteristics allow the purification and isolation after homogenization, heating the extract, centrifugation, filtration and posterior determination and quantification by capillary electrophoresis. This is a rapid and reproducible technique to establish the MT concentration in biological samples
