INCORPORATION OF RADIOACTIVE COMPOUNDS INTO THE PURINE AND PYRIMIDINE BASES AND 2-DEOXYRIBOSE OF SALMON TESTES DEOXYRIBONUCLEIC ACID

Abstract

Slices of immature salmon testes incorporated radioactive purine and pyrimidine bases and related nucleosides, deoxynucleosides, nucleotides, and deoxynucleotides into deoxyribonucleic acid (DNA). When DNA was extracted from the tissues and hydrolyzed, the purine and pyrimidine bases obtained were labeled in a manner which suggested that the radioactive substrates had been incorporated into DNA by recognized biosynthetic pathways involving "preformed" purines and pyrimidines and their derivatives. Since radioactive carbonate, glycine, and formate were not incorporated into the purines obtained from DNA, and radioactive formate only caused labeling of the thymine, it would appear unlikely that the de novo biosynthesis of purine and pyrimidine rings occurs in milts. C-1, C-6, and generally labeled glucose-14C caused labeling of the 2-deoxyribose, but not of the purines or pyrimidines, of DNA. Radioactive adenylic acid, deoxyuridylic acid, ribose 5-phosphate, and 5-phospho-α-D-ribofuranosyl-1-pyrophosphate also caused labeling of the 2-deoxyribose of DNA.