Mutagenesis of free and intracellular cyanophage AS-1 by ultraviolet, N-methanyl-N'-nitro-N-nitrosoguanidine and acriflavine

Mutat Res. 1979 Feb;59(2):147-55. doi: 10.1016/0027-5107(79)90152-0.


Mutagenic actions of ultraviolet irradiation (UV), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and acriflavine (photodynamic) were tested in free and intracellular phage AS-1 infecting Anacystis nidulans IU625. Spontaneous and induced mutations with particular reference to host range (h) and minute plaque formation (m) were investigated. The spontaneous mutation frequencies varied from 10(-9) to 10(-8) and from 2 X 10(-5) to 2 X 10(-4) for h and m mutants respectively. UV was efficient in inducing h and m markers in free phage particles as well as intracellular phage; MNNG induced both markers in intracellular phage only, and acriflavine induced m mutants only in free as well as in infecting phages. UV-induced mutations in free phage were photo-reactivable by visible light. With all the mutagens used, maximal induction of both markers was observed with treatment of 2-h complexes.

MeSH terms

  • Acriflavine / pharmacology
  • Cyanobacteria*
  • Gene Frequency
  • Methylnitronitrosoguanidine / pharmacology
  • Mutagens
  • Mutation*
  • Ultraviolet Rays
  • Viruses / drug effects
  • Viruses / genetics*
  • Viruses / radiation effects


  • Mutagens
  • Methylnitronitrosoguanidine
  • Acriflavine