Studies on the Biosynthesis of Nucleic Acids. I. On the Role of 4-Aminoimidazole-5-carboxamide as a Precursor of Polynucleotide Purines

Abstract

By employing 4-aminoimidazole[4-¹⁴C]-5-carboxamide, formate-¹⁴C, and ³²P, the role of the carboxamide as a precursor of polynucleotide purines was examined. The in vitro incorporation of the labeled carboxamide into polynucleotide adenine and guanine was found by rat liver slices and by cell-free system. The specific activity was about 2∼5 times higher in adenine than in guanine. In the case of regenerating liver, generally higher specific activity was observed than in the case of normal liver. The stimulatory effect of the non-labeled carboxamide in the course of the incorporation of formate-¹⁴C and ³²P into polynucleotides was demonstrated.