[Sulfur metabolism and its regulation in plants].

Sulfur, one of the vital macroelements, is present in nature in several redox forms (S(+VI), S(+IV), S(+II), S0). In most organic compounds sulfur is present in the reduced form (S(-II)), while most inorganic sulfur is oxidized, in a form of sulfate (S(+VI)). Animals and humans can incorporate only the organic forms of sulfur, present in sulfur-containing amino acids. Plants, most bacteria and fungi are able to uptake inorganic sulfate, gradually reduce it and assimilate it into variety of organic compounds. Knowledge of the regulatory mechanisms of this process is a key factor for understanding relationships between availability of sulfur source and plant growth and development, their resistance to environmental stresses and nutritional value of edible crops. Recently, a number of research groups conducted intensive investigations on sulfur metabolism and its regulation in plants. The aim of this review is to inform the Polish reader about the new results and concepts in this field.