ACRIDINE ORANGE RESISTANT MUTANT OF BACTERIOPHAGE LAMBDA

During incubation of a mixture of phage lambda and acridine orange in a solution of low ionic force at a pH of 7.6, dark inactivation of the phage takes place. A phage mutant was isolated and described it is resistant to acridine orange both within and outside the cell. Acquisition of resistance to the dye cannot be the result of impermeability of the mutants protein membrane for dye molecules. No differences were detected between the absorption spectra and melting curves of nucleic acids in the mutant and wild type phage. Both DNAs modify identically the spectrum of acridine orange.