The molecular mechanism of virus induction

Abstract
The basic conditions for use of a new biochemical assay of bacteriophage induction are described. This method is based on the read-through transcription of the tryptophan operon integrated into an “early” transcribed region of the bacteriophage ϕ80 or λ genome. Inactivation of repressor molecules was assayed by measuring, in the presence of tryptophan, anthranilate synthetase activity in an Escherichia coli (trpE ) ϕ80 or λ lysogen infected with ϕ80ptrp or λptrp, respectively, and treated with mitomycin C or UV irradiation. This method provides a sensitive and easy means to analyze the induction process.