9-Aminoacridine mutagenesis of bacteriophage T4 intracellular DNA.

Most of the intracellular T4 DNA made in the presence of 9-aminoacridine is of lower molecular weight than mature T4 DNA and does not get packaged into phage particles. Using a T4 DNA transformation assay, we have examined this intracellular T4 DNA for its content of 9-aminoacridine-induced revertants of certain rII gene frameshift mutations. The proportion of acridine-induced revertants in the intracellular DNA population is close to that found in the phage progency made in the presence of 9-aminoacridine. Thus, the generation of low molecular weight T4 DNA in the presence of 9-aminoacridine is not, in itself, also a mutagenic process.