A new strategy for the increase of Arginine in plants was investigated, the Coexpression of Arg rich Cyanophycin (CGP) and its degrading enzyme Cyanophycinase (CGPase). The CGP production in plants was optimized for a commercial application and CGPase expression in plants established by transient expression. Enzyme and substrate could be coexpressed in one plant and CGP degradation was shown in plant material. This degradation was also shown in the intestine of mice, which did not lead to an increase of Arg, but of b-Asp-Arg dipeptides in the blood.<eng>
