Resistance of bacteriophage PBS2 infection to 6-(p-hydroxyphenylazo)-uracil, an inhibitor of Bacillus subtilis deoxyribonucleic acid synthesis.

6-(p-Hydroxyphenylazo)-uracil (HPUra), an inhibitor of semiconservative deoxyribonucleic acid (DNA) synthesis in Bacillus subtilis, does not prevent (but slightly reduces the rate of) replication of the uracil-containing DNA phage PBS2. Our observations are consistent with the hypothesis that all B. subtilis phages which are resistant to HPUra are able to induce a new DNA polymerase activity.