Influence of copper on the accumulation of iron by the root polyuronic components

The polyuronic substances, main components of root cells walls and inner apoplast, play an important role in the absorption of micro-,macronutrients and heavy metals by plants being able to bind them through the formation of complexes of different nature. Thus, they can behave as accumulation of iron onto a Ca-polygalacturonate network used as a model of the inner and outer apoplast of the root epidermal cells. In particular, the ability of the polysaccharidic matrix to accumulate these metal ions and its dependence on the mechanism of interaction between each ion and the binding sites of the polyelectrolyte, in both the absence and presence of organic acids, are concerned.