BIOSYNTHESIS OF NUCLEOTIDES IN WHEAT: III. PURINE AND PYRIMIDINE NUCLEOTIDES FROM P32-LABELLED PHOSPHATE

Abstract
Phosphate labelled with p32 was fed to viable wheat embryos with and without 5-amino-4-imidazole carboxamide (AICA). The cold perchloric acid fraction was treated with Norit A; the absorbed nucelotides were eluted by pyridine-alcohol and subjected to chromatographic analysis for identification. Approximately 30% of the label in the soluble fraction was incorporated into identifiable purine and pyrimidine nucleotides. AICA had no effect on the amount of incorporation. This study shows the existence of a pool of free nucleotides in wheat embryos.