Effect and mechanism of action of aphidicolin on yeast deoxyribonucleic acid polymerases

The antibiotic aphidicolin inhibited in vitro deoxyribonucleic acid synthesis catalyzed by crude yeast extracts and by partially purified yeast deoxyribonucleic acid polymerases. The mechanism of action of aphidicolin on yeast deoxyribonucleic acid polymerase I was noncompetitive with deoxyguanosine 5'-triphosphate, deoxyadenosine 5'-triphosphate, and deoxythymidine 5'-triphosphate and was of mixed type with deoxycytidine 5'-triphosphate. The relative ratio of enzyme to the template-initiator complex was important for detecting the inhibitory effect of the antibiotic. The inhibition of in vitro deoxyribonucleic acid synthesis by aphidicolin was reversible, and the effect on yeast deoxyribonucleic acid polymerase might have been partially mediated by some supplementary factor(s).