The Relationship Between Cyanide Assimilation and Asparagine Biosynthesis in Lupins

ß-cyanoalanine synthese in etolated seedlings of Lupinusangustifolius is found mainly in the mitochondrial fractionof the cotyledons and stems. In seedlings developing at 25°Cin the dark it reaches a maximal concentration after 5 days,at the same time as asparagine accumulation is most rapid andother physiological changes occur. However, maximal abiliatyto assimilate HCN gas to asparagine develops after 3 to 4 days,before asparagine accumulation begins. The possibility thatthe ß-cyanoalanine pathway is a major route for asparaginebiosynthesis in lupin seedlings is concluded to be unlikely.