The inhibition of purine biosynthesis De novo in Bacillus subtilis by cordycepin

Abstract

1. 1. Cordycepin has been shown to inhibit purine biosynthesis de novo as evidenced by a decreased incorporation of radioactive formate into the nucleic acid purines of Bacillus subtilis. 2. 2. The incorporation of radioactive 5-amino-4-imidazolecarboxamide into the purine ring was not severely inhibited by cordycepin. 3. 3. Radiautography of an alcohol-soluble extract of B. subtilis which were grown with cordycepin and either radioactive formate or glycine failed to show an accumulation of any intermediates. 4. 4. The formation of formylglycinamide ribonucleotide, which was caused to accumulate by the addition of 6-diazo-5-oxo- l-norleucine, was suppressed in the presence of cordycepin. These results indicate that in B. subtilis cordycepin inhibits a step in purine biosynthesis de novo which is prior to the formation of glycinamide ribonucleotide.