Ureide Metabolism in Non-nodulated Phaseolus vulgaris L.

The distribution of ureide-N was studied throughout vegetative and reproductive growth of non-nodulated Phaseolus vulgaris L. (bushbean) grown in nitrate nutrient solution. Largest increases in ureide-N per plant were correlated with flowering and early pod formation and with seed filling. Highest amounts of ureides per organ were measured in stems and axillary trifoliates. Highest concentrations (μmol ureide-N g−1 fr. wt.) were measured in young developing organs and stems. Seeds did not accumulate ureides until the ureide content of pods had reached a maximum.
Results obtained using the inhibitor of xanthine oxidase, allopurinol, are consistent with the origin of ureides via purine degradation but alternative pathways cannot be discounted.
Leaves and stems were shown to have the ability to degrade allantoate via an enzymic process.