[Effect of substances altering the DNA molecular conformation on plasmid transformation, plasmid recombination and plasmid transduction in Bacillus subtilis].

The influence of ethidium bromide, actinomycin D and acridine orange treatment of Bacillus subtilis competent cells on plasmid transformation, recombination and transduction was studied. The drugs were administered at different times after DNA uptake. The yield of plasmid recombinants and transformants was inhibited in different ways during the first 30 minutes. Probably, it was the result of damaging the synaptic stage of recombination because of DNA conformational changes. The effect of drugs on plasmid transduction was significantly lesser.