Effect of 8-azaguanine on growth and viability of Bacillus megaterium.

Mangalo, R. (University of Illinois, Urbana) and J. T. Wachsman. Effect of 8-azaguanine on growth and viability of Bacillus megaterium. J. Bacteriol. 83:27-34. 1962.-The addition of 8-azaguanine to exponentially growing cells of Bacillus megaterium results in an inhibition of growth after a lag of approximately 30 min. However, 8-azaguanine-2-C(14) is incorporated into the nucleic acids in a linear fashion without a detectable lag. The inhibitory action is reversed by purines and their derivatives, but not by uridine, thymidine, or cytidine. 8-Azaguanine is bactericidal, especially under conditions where growth (ribonucleic acid synthesis) is possible. Growth in the presence of a complete amino acid mixture, either before or during exposure to 8-azaguanine, increases the rate of killing. Chloramphenicol has little or no effect on the bactericidal action of the analogue.