Early blocked asporogenous mutants of Bacillus subtilis are lysogenized at reduced frequency by temperate bacteriophages

Abstract

The establishment of lysogeny in early-blocked asporogenous (Spo-) mutants of B. subtilis 168, which were also defective in the production of antibiotics (Abs-), by temperate phage ∅105 or SPO2 was studied. It was found that the frequency of lysogenization of Spo- Abs- mutants was 10 to 20% that of the wildtype bacteria. There was no difference in the efficiency of plating and the burst size of ∅105 between the wild-type and mutant strains. ∅105 lysogens of mutant strains were as stable as those of the wild type. Several rifampin-resistant mutants defective in the production of antibiotics were isolated. They were also defective in spore formation and lysogenized by φ105 at reduced frequency.